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  • Articles  (166)
  • 42.55  (108)
  • Animals
  • Chemical Engineering
  • Electronic structure and strongly correlated systems
  • salinity
  • temperature
  • Springer  (166)
  • Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics  (131)
  • Geography  (31)
  • Architecture, Civil Engineering, Surveying  (6)
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  • Articles  (166)
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  • 1
    Electronic Resource
    Electronic Resource
    Successive Approximation Linear Quadratic Regulator for Estuarine Management Problem (2000)
    Springer
    Water resources management 14 (2000), S. 157-175 
    Details
    ISSN: 1573-1650
    Keywords: estuarine management ; fishery harvest ; freshwater inflow ; linear quadratic regulator ; salinity ; successive approximation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying , Geography
    Notes: Abstract A successive approximation linear quadratic regulator (SALQR)method is applied to solve estuarine management problems to determine the optimal amount of freshwater inflows into baysand estuaries to maximize fishery harvests. Fishery harvests areexpressed in regression equations as functions of freshwaterinflows. The optimization problem is posed as a discrete-timeoptimal control problem in which salinity represents the statevariable and freshwater inflow represents the control variable. A two-dimensional hydrodynamic-salinity transport model, HYD-SAL,is used as the transition to simulate the flow circulation andtemporal and spatial salinity pattern in an estuary system. Thebound constraints for the control and state variables areincorporated into the objective function using a penalty functionmethod to convert the problem into an unconstrained formulation. The SALQR method is applied to the Lavaca-Tres Palacios Estuaryin Texas and the results are compared with those of usingregression equations as the transition equations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1026576129765
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  • 2
    Electronic Resource
    Electronic Resource
    Effect of Boron on the Structure and Composition of Cobalt Silicides (2000)
    Springer
    Powder metallurgy and metal ceramics 39 (2000), S. 599-602 
    Details
    ISSN: 1573-9066
    Keywords: solid-phase reaction ; solubility ; temperature ; cobalt silicides ; boron
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The system Co ― Si ― B is promising for development of new soft magnetic materials. We studied the effect of boron on the structure and composition of cobalt silicides during solid-phase reaction of powders of the starting components under a 3·10−3 Pa vacuum in the temperature range 200°C to 1300°C for boron content from 0.5 mass% to 7.7 mass% by differential thermal analysis, metallographic analysis, x-ray analysis, and electron-probe microanalysis. We established that boron is not soluble in cobalt silicides. Formation of ternary chemical compounds is typical for the Co ― Si ― B system.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1011384332153
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  • 3
    Electronic Resource
    Electronic Resource
    Dynamics of the Subsurface Temperature Field Caused by Mining-Related Groundwater Management (2000)
    Springer
    Studia geophysica et geodaetica 44 (2000), S. 442-459 
    Details
    ISSN: 1573-1626
    Keywords: temperature ; groundwater ; sedimentary basin ; exploitation ; transient effects
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying , Geosciences , Physics
    Notes: Abstract The subsurface temperature field was studied on a set of 46 borehole logs measured in the vicinity of uranium deposits in the Bohemian Cretaceous Basin. Vertical variations of the steady state temperature and the temperature gradient are governed by thermal conductivity which strongly varies in dependence on lithology. Large departures from undisturbed temperature detected in many holes are associated with uranium mining. A positive anomaly is observed in leaching fields where large amounts of acid are injected into the uranium-bearing Cenomanian. A negative anomaly is linked to the operation of hydraulic barriers which enclose the mining area and helps to contain pollution by pumping clean water into the Cenomanian aquifer. The spatial distribution of the observed temperature anomalies helps to map the migration of the fluids used in both processes. The temperature disturbance is propagated from the Cenomanian aquifer up through overlying impermeable sediments. The good fit of transient conductive models to the measured temperatures rules out heat advection and hence upward water flow towards and contamination of the upper Middle Turonian aquifer in the vicinity of the holes studied.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1022168705973
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  • 4
    Electronic Resource
    Electronic Resource
    Magnéli phases of anion-deficient rutile as lubricious oxides. Part I. Tribological behavior of single-crystal and polycrystalline rutile (Ti n O2n−1) (2000)
    Springer
    Tribology letters 8 (2000), S. 65-78 
    Details
    ISSN: 1573-2711
    Keywords: solid lubricants ; lubricious oxides ; TiO2 ; rutile ; oxygen stoichiometry ; Magnéli phases ; tribometry ; friction ; wear ; shear strength ; temperature ; atmosphere ; extreme environment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract In part I of this paper series, wide temperature range SEM-tribometric results generated in vacuum and various partial pressures of oxygen are combined with relevant literature data to examine a hypothesis correlating the oxygen stoichiometry of the Ti n O2n−1 Magnéli phases of the rutile polymorph of titania with their tribological behavior. Single-crystal and polycrystalline rutile specimens of narrow stoichiometry ranges were sliding against α-SiC and themselves. The surface shear strength changes were determined as a function of the thermal–atmospheric test environment, and the shear strength values were estimated by the coefficients of friction, the real area of contact and the published yield strength of rutile. The data appear to be sufficient and sufficiently reliable to confirm the accuracy of the hypothesis. The tendency of the rutile stoichiometry (ergo the friction) to shift as a function of temperature and partial pressure of oxygen causes this material to be thermo-oxidatively unstable for tribological applications in extreme environments. In part II, a study is described to formulate oxidatively more stable Magnéli phases by Cu-doping, and test the new materials by SEM tribometry using a procedure used for pure rutile here in part I. By employing this doping methodology similar to creating high-temperature superconductive oxides in part II, some feasibility of producing oxidatively stable, lubricious oxides with acceptably low wear rates is indicated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1019122915441
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  • 5
    Electronic Resource
    Electronic Resource
    FTIR spectroscopy and nanotribological comparative studies: influence of the adsorbed water layers on the tribological behaviour (2000)
    Springer
    Tribology letters 9 (2000), S. 111-117 
    Details
    ISSN: 1573-2711
    Keywords: AFM ; force ; friction ; adhesion ; molecular water layer ; temperature ; capillary forces ; PMIRRAS
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Under ambient conditions, a water film is always present on a silica substrate and generates additional capillary forces between the nanotip and the studied surface. In the present paper, we report AFM measurements of pull-off and friction forces as a function of the temperature and a comparative FTIR spectroscopy study. The AFM results show a net decrease of the forces as the temperature increases, while the IR spectroscopy indicates that the liquid film is removed at high temperature. Consequently, we deduce that a liquid neck is created between the tip and the surface and that the forces measured are mostly capillary forces. The present work shows that temperature studies with AFM can be a useful way to probe the influence of the capillary force in turn to characterize surface properties.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1018868830205
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  • 6
    Electronic Resource
    Electronic Resource
    Magnéli phases of anion-deficient rutile as lubricious oxides. Part II. Tribological behavior of Cu-doped polycrystalline rutile (Ti n O2n−1) (2000)
    Springer
    Tribology letters 8 (2000), S. 79-96 
    Details
    ISSN: 1573-2711
    Keywords: solid lubricants ; lubricious oxides ; TiO2 ; rutile ; oxygen stoichiometry ; Magnéli phases ; tribometry ; friction ; wear ; shear strength ; temperature ; atmosphere ; extreme environment ; molecular engineering ; cation doping ; aliovalency
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract As a follow-up to the work described in part I of this paper series, a preliminary study was conducted with polycrystalline rutile TiO−x to render its friction and wear performance independent of the environment. The main goal was to confine the most tribologically desirable oxygen stoichiometries of the crystallographic shear-induced Magnéli phases (CSMP) of rutile by doping with cations similar in size and polarizability to the Ti4+, but with lower valences. The resultant chemical expulsion of oxygen from the rutile lattice was intended to generate CSMP free of friction and wear variations caused by changes in the thermal–atmospheric environment. Copper, iron, cobalt and nickel ions were tried as dopants introduced as their stable oxides via a simple ball-milling, hot-pressing and annealing procedure, but only a (Ti + Cu)O1.80 model blend resulted in a desired reaction. A portion of the copper entered the lattice to form a new titanium–copper CSMP, resembling the well-known V3Ti6O17 catalyst equivalent to an undoped rutile CSMP with an O/Ti ratio of 1.89. Although the shear behavior of this new, wear-resistant compound was in accordance with predictions, its friction is higher and more variable than desired for a wide environmental regime lubricant. The preparation technique was only sufficient to demonstrate that oxygen vacancy-induced creation of low-friction CSMP may be possible by doping; it does not appear to be useful for formulating practical, rutile-based lubricious oxides.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1019174932279
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  • 7
    Electronic Resource
    Electronic Resource
    Temperature Effects on Soil Mineralization of Polylactic Acid Plastic in Laboratory Respirometers (1999)
    Springer
    Journal of polymers and the environment 7 (1999), S. 101-108 
    Details
    ISSN: 1572-8900
    Keywords: Polylactic acid ; temperature ; respirometers ; soil degradation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Energy, Environment Protection, Nuclear Power Engineering , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract A respirometric system was used to analyze the biodegradation of high molecular weight (120,000 to 200,000 g mol−1) polylactic acid (PLA) plastic films in soil under laboratory conditions. The respirometric system consisted of air-conditioning pretraps, a soil reactor, and a carbon dioxide (CO2) posttrap. A 200-g homogeneous soil mixture of all-purpose potting soil : manure soil : sand [1 : 1 : 1 (w/w)] and 1.5 g of PLA plastic films in 1 × 1-cm2 squares was added to each bottle. The respirometers were placed in a 28, 40, or 55°C water bath for 182 days. Treatments (three replicates) included native corn starch (positive control), polyethylene (Glad Cling Wrap; negative control), and three PLA films: Ca-I (Cargill Dow Polymers LLC, monolayer), GII (Cargill Dow Polymers LLC, Generation II), and Ch-I (Chronopol; monolayer). The degree of polymer mineralization was indicated by the cumulative CO2 liberated from each respirometer. The initial average mineralization rate and total percentage mineralized of the PLA plastic films at 28, 40, and 55°C was 24.3, 41.5, and 76.9 mg/day with a 27, 45, and 70% carbon loss, respectively. No decrease in soil pH was observed after 182 days of mineralization. Hence, increase in soil temperature drastically enhanced the biodegradation of PLA plastic films in soil under laboratory conditions (P 〈 0.0001).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1021812418325
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  • 8
    Electronic Resource
    Electronic Resource
    Effects of Temperature and Relative Humidity on Polylactic Acid Plastic Degradation (1999)
    Springer
    Journal of polymers and the environment 7 (1999), S. 83-92 
    Details
    ISSN: 1572-8900
    Keywords: Polylactic acid ; temperature ; relative humidity ; degradation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Energy, Environment Protection, Nuclear Power Engineering , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Three high molecular weight (120,000 to 200,000 g mol−1) polylactic acid (PLA) plastic films from Chronopol (Ch-I) and Cargill Dow Polymers (GII and Ca-I) were analyzed for their degradation under various temperature and relative humidity (RH) conditions. Two sets of plastic films, each containing 11 samples, were randomly hung in a temperature/humidity-controlled chamber by means of plastic-coated paper clips. The tested conditions were 28, 40, and 55°C at 50 and 100% RH, respectively, and 55°C at 10% RH. The three tested PLA films started to lose their tensile properties when their weight-average molecular weight (M w) was in the range of 50,000 to 75,000 g mol−1. The average degradation rate of Ch-I, GII, and Ca-I was 28,931, 27,361, and 63,025 M w/week, respectively. Hence, GII had a faster degradation rate than Ch-I and Ca-I under all tested conditions. The degradation rate of PLA plastics was enhanced by the increase in temperature and relative humidity. This trend was observed in all three PLA plastics (Ca-I, GII, and Ch-I). Of the three tested films, Ch-I was the first to lose its mechanical properties, whereas Ca-I demonstrated the slowest loss, with mechanical properties under all tested conditions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1021808317416
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  • 9
    Electronic Resource
    Electronic Resource
    Algae of Lake Bai-Khol (Tuva, Russia) (1999)
    Springer
    International journal of salt lake research 8 (1999), S. 171-176 
    Details
    ISSN: 1573-8590
    Keywords: algae ; Lake Bai-Khol ; salinity ; Uvs-Nuur Basin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract The algal flora of Lake Bai-Khol, located in the endorheic Uvs-Nuur Basin, Russia, has been studied from collections made in August 1997. 79 taxa belonging to diatoms, blue-green and green algae were present.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009019616569
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  • 10
    Electronic Resource
    Electronic Resource
    A spatio-chemical survey of hydrogeothermal springs in Lake Elementaita, Kenya (1999)
    Springer
    International journal of salt lake research 8 (1999), S. 127-138 
    Details
    ISSN: 1573-8590
    Keywords: Lake Elementaita ; Lake Nakuru ; origin ; salinity ; thermal springs ; water chemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract The hydrochemistry of three areas of geothermal activity in the Lake Elementaita basin were surveyed. The results indicated warm temperatures between 30--40°C, high alkalinity (1,200 mg CaCO3/l) and specific conductance (4,300--8,100 µS/cm). pH was above 9 with a high concentration of carbonates, chlorides and sulphates. Apart from playing a significant role in the lake chemistry, lacustrine springs provide a significant source of water supply, particularly during the dry season. However, there is a serious lack of scientific information on the hydrogeology and hydrochemistry of the thermal springs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009023717477
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  • 11
    Electronic Resource
    Electronic Resource
    Comparisons between the reproductive biology of black breamAcanthopagrus butcheri (Teleostei: Sparidae) in four estuaries with widely differing characteristics (1999)
    Springer
    International journal of salt lake research 8 (1999), S. 179-210 
    Details
    ISSN: 1573-8590
    Keywords: black bream ; estuaries ; fecundity ; fishery management ; length and age at maturity ; salinity ; spawning periods and locations ; water temperature
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract The reproductive biology ofAcanthopagrus butcheri has been studied in the permanently open Swan River and intermittently open Moore River estuaries on the lower west coast of Australia (31–32°S) and in the permanently open Nornalup Walpole and normally closed Wellstead estuaries on the southern coast of Western Australia (34–35°S). Trends exhibited by gonadosomatic indices, gonadal maturity stages and the sizes and developmental stages of the oocytes demonstrate thatA. butcheri typically spawns in spring and early summer. However, spawning occurred in salinities ranging from as low as 3.5–8 gL−1 in the Moore River Estuary to as high as 41–45 g L−1 in the Wellstead Estuary. Furthermore, water temperatures during spawning were greater in the two northern estuaries (19.7–28.5°C) than in the two southern and cooler estuaries (17.5–23.4°C). Histological studies strongly indicate thatA. butcheri spawn more than once in a breeding season and demonstrate that the development of its oocytes exhibits group synchronysensu de Vlaming (1983). The ages and total lengths at which, on average, female and maleA. butcheri both first attain maturity in the Swan River Estuary were ca 2 years and ca 215 mm. However, the age at which individual fish in that system reach maturity was influenced by body size. This suggests that the attainment of first maturity at an older age but smaller length in the Moore River and Nornalup Walpole estuaries than is the case in the Swan River Estuary is a consequence of the slower growth rates ofA. butcheri in those estuaries. The combination of the young age (ca 2 years) but small length (ca 145 mm) at which maturity is first attained in the Wellstead Estuary could have resulted from selection pressures brought about by high mortality rates and/or heavy fishing pressure in this estuary. The mean fecundity ofA. butcheri, based on the combined number of yolk vesicle and yolk granule oocytes found in ovaries just prior to the onset of spawning, was 1580×103. The significance of the sizes at first maturity, minimum legal length for capture, mesh selectivity data and closure of certain regions of estuaries to fishing for the management of the recreational and commercial fishery forA. butcheri is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02449931
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  • 12
    Electronic Resource
    Electronic Resource
    Salinity of surface waters in the Aral Sea region (1999)
    Springer
    International journal of salt lake research 8 (1999), S. 293-306 
    Details
    ISSN: 1573-8590
    Keywords: Aral Sea ; salinity ; salinization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract An overview of recent changes insalinity in the surface waters of the Aral sea basinis given. Total dissolved salts (salinity) in mostwaters are higher than admissible values fordrinking water, and ionic composition has changed withtime. Salinity of the `Big Sea' of the Aral was 48g L−1 in 1998, but has decreased to below 21g L−1 in the `Small Sea' due to the building ofa new dam between the two parts of the Aral Sea.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009082722430
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  • 13
    Electronic Resource
    Electronic Resource
    A spatio-chemical survey of hydrogeothermal springs in Lake Elementaita, Kenya (1999)
    Springer
    International journal of salt lake research 8 (1999), S. 127-138 
    Details
    ISSN: 1573-8590
    Keywords: Lake Elementaita ; Lake Nakuru ; origin ; salinity ; thermal springs ; water chemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract The hydrochemistry of three areas of geothermal activity in the Lake Elementaita basin were surveyed. The results indicated warm temperatures between 30–40°C, high alkalinity (1,200 mg CaCO3/l) and specific conductance (4,300–8,100 μS/cm). pH was above 9 with a high concentration of carbonates, chlorides and sulphates. Apart from playing a significant role in the lake chemistry, lacustrine springs provide a significant source of water supply, particularly during the dry season. However, there is a serious lack of scientific information on the hydrogeology and hydrochemistry of the thermal springs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02442126
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  • 14
    Electronic Resource
    Electronic Resource
    Hydrological exchange and subsurface water chemistry in streams varying in salinity in south-western Australia (1999)
    Springer
    International journal of salt lake research 8 (1999), S. 361-382 
    Details
    ISSN: 1573-8590
    Keywords: Aral Sea ; salinity ; salinization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract Many streams in Western Australia are naturally saline. In others, especiallyin the south-western corner, land-clearance and other human activities inthe catchment have accelerated rates of salinisation of surface andgroundwater. Trends in surface water salinity are well-documented but theextent of penetration of saline stream water into the sediments has beenlittle studied. As many of these streams have porous sandy beds and theirflows may derive from groundwater, hydrologic exchange patterns betweensurface water and subsurface hyporheic water were hypothesised togovern the water chemistry of such rivers. We predicted high rates ofhydraulic conductivity, leading to a close relationship between surface andsubsurface (to a depth of 50 cm) salinity, and to a lesser extent, pH anddissolved oxygen. Where surface and hyporheic water differed in salinity,other chemical differences were hypothesised to be similarly marked,perhaps resulting from disjunct shallow subsurface aquifers. Triplicatewells were sampled from upwelling and downwelling zones of thirteenstreams ranging in salinity from ca. 0.2 to 18 g L−1. Despite theseemingly-porous sandy beds at many sites, subsurface water chemistryonly 20–40 cm below the bed sometimes differed markedly from surfacewater. For example, hyporheic water was only one-fifth the salinity ofsurface water at some saline sites (e.g., the Tone River) or 20 per cent moresaline in streams with fresh surface water (e.g., the Weld River). At somesites of intermediate salinity (e.g., the Warren River), subsurface water wasup to three times fresher than surface or downwelling water. Percentagesaturation of dissolved oxygen in the hyporheic water was consistently low(〈 40%) whereas pH was more acidic than surface water, presumably dueto microbial activity. Vertical hydraulic conductivity may be limited bylayers of fine sediments and clays, implying that the meso-scale (1–100 cm)hydrological dynamics within the hyporheic zones of these rivers are morecomplex than their sandy beds would indicate. Assumptions of ecosystemdynamics in saline streams must be tempered by an understanding ofhyporheic salinities as subsurface fresher water may support microbial andfaunal assemblages excluded from the surface benthos by high salinity. Insaline streams, as in fresh ones, the hyporheic zone is an importantcomponent of the stream ecosystem and equally prone to disruption byhuman activities.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009060912470
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  • 15
    Electronic Resource
    Electronic Resource
    The salinity of hypersaline brines: Concepts and misconceptions (1999)
    Springer
    International journal of salt lake research 8 (1999), S. 55-70 
    Details
    ISSN: 1573-8590
    Keywords: Dead Sea ; equation of state ; pycnometry ; salinity ; saturation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract Some widespread misconceptions about salinity are pointed out, explained and commented on. Definitions, units, and methods of salinity determination recommended for brines of moderate salinities may become unsuitable for highly saline brines. Various salinity units are examined and commented on, and density at a precisely monitored temperature is chosen as the preferable “substitute parameter” for salinity determination of hypersaline brines. It is shown that ambient air density during pycnometric measurements must be known as accurately as required of the brine's density, and that its value must be added to the direct pycnometric measurement. Variations of atmospheric pressure at the time of pycnometry must be taken into account if greater than 15 mB. For a salinity accuracy of ±0.02 per mille, as required for some physical and chemical studies, the temperature of the sample during salinity measurement must be monitored with an accuracy of at least 0.04°C. A definite curve in the ρ-S plane, corresponding to the conversion of salinity to density at a fixed temperature, andvice-versa, does not exist if the brine is saturated in one of its salts. Non-linearity in the equation of state is shown to affect the surface level drop due to evaporation; the effect is negligible at low salinities, but a 10 per cent correction is already required at the salinity found in the northern Red Sea (41 per mille). Reliable reference points for the conversion of absolute salinity to density of highly saline brines are not known, at present, as accurately as desirable; pending the accurate determination of such reference points, a substantial dilution of hypersaline brines (for the purpose of adapting them to conductivity measurements) would multiply the error range by more than a hundred fold. On the other hand, a minute dilution of hypersaline brine samples to prevent salt crystal formation is possible and would not bring about any major increase of the error range in their density (salinity) determination.
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    URL: http://dx.doi.org/10.1007/BF02442137
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  • 16
    Electronic Resource
    Electronic Resource
    Algae of Lake Bai-Khol (Tuva, Russia) (1999)
    Springer
    International journal of salt lake research 8 (1999), S. 171-176 
    Details
    ISSN: 1573-8590
    Keywords: algae ; Lake Bai-Khol ; salinity ; Uvs-Nuur Basin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract The algal flora of Lake Bai-Khol, located in the endorheic Uvs-Nuur Basin, Russia, has been studied from collections made in August 1997. 79 taxa belonging to diatoms, blue-green and green algae were present.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02442129
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  • 17
    Electronic Resource
    Electronic Resource
    The salinity of hypersaline brines: Concepts and misconceptions (1999)
    Springer
    International journal of salt lake research 8 (1999), S. 55-70 
    Details
    ISSN: 1573-8590
    Keywords: Dead Sea ; equation of state ; pycnometry ; salinity ; saturation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract Some widespread misconceptions about salinity are pointed out, explained and commented on. Definitions, units, and methods of salinity determination recommended for brines of moderate salinities may become unsuitable for highly saline brines. Various salinity units are examined and commented on, and density at a precisely monitored temperature is chosen as the preferable “substitute parameter” for salinity determination of hypersaline brines. It is shown that ambient air density during pycnometric measurements must be known as accurately as required of the brine's density, and that its value must be added to the direct pycnometric measurement. Variations of atmospheric pressure at the time of pycnometry must be taken into account if greater than 15 mB. For a salinity accuracy of ±0.02 per mille, as required for some physical and chemical studies, the temperature of the sample during salinity measurement must be monitored with an accuracy of at least 0.04°C. A definite curve in the ρ-S plane, corresponding to the conversion of salinity to density at a fixed temperature, and vice-versa, does not exist if the brine is saturated in one of its salts. Non-linearity in the equation of state is shown to affect the surface level drop due to evaporation; the effect is negligible at low salinities, but a 10 per cent correction is already required at the salinity found in the northern Red Sea (41 per mille). Reliable reference points for the conversion of absolute salinity to density of highly saline brines are not known, at present, as accurately as desirable; pending the accurate determination of such reference points, a substantial dilution of hypersaline brines (for the purpose of adapting them to conductivity measurements) would multiply the error range by more than a hundred fold. On the other hand, a minute dilution of hypersaline brine samples to prevent salt crystal formation is possible and would not bring about any major increase of the error range in their density (salinity) determination.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009059827435
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  • 18
    Electronic Resource
    Electronic Resource
    Comparisons between the reproductive biology of black bream Acanthopagrus butcheri (Teleostei: Sparidae) in four estuaries with widely differing characteristics (1999)
    Springer
    International journal of salt lake research 8 (1999), S. 179-210 
    Details
    ISSN: 1573-8590
    Keywords: black bream ; estuaries ; fecundity ; fishery management ; length and age at maturity ; salinity ; spawning periods and locations ; water temperature
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract The reproductive biology of Acanthopagrus butcheri has been studied in the permanently open Swan River and intermittently open Moore River estuaries on the lower west coast of Australia (31--32 °S) and in the permanently open Nornalup Walpole and normally closed Wellstead estuaries on the southern coast of Western Australia (34--35 °S). Trends exhibited by gonadosomatic indices, gonadal maturity stages and the sizes and developmental stages of the oocytes demonstrate that A. butcher typically spawns in spring and early summer. However, spawning occurred in salinities ranging from as low as 3.5-8 g L−1 in the Moore River Estuary to as high as 41-45 g L−1 in the Wellstead Estuary. Furthermore, water temperatures during spawning were greater in the two northern estuaries (19.7--28.5 °C) than in the two southern and cooler estuaries (17.5--23.4 °C). Histological studies strongly indicate that A. butcheri spawn more than once in a breeding season and demonstrate that the development of its oocytes exhibits group synchrony sensu de Vlaming (1983). The ages and total lengths at which, on average, female and male A. butcheri both first attain maturity in the Swan River Estuary were ca 2 years and ca 215 mm. However, the age at which individual fish in that system reach maturity was influenced by body size. This suggests that the attainment of first maturity at an older age but smaller length in the Moore River and Nornalup Walpole estuaries than is the case in the Swan River Estuary is a consequence of the slower growth rates of A. butcheri in those estuaries. The combination of the young age (ca 2 years) but small length (ca 145 mm) at which maturity is first attained in the Wellstead Estuary could have resulted from selection pressures brought about by high mortality rates and/or heavy fishing pressure in this estuary. The mean fecundity of A. butcheri, based on the combined number of yolk vesicle and yolk granule oocytes found in ovaries just prior to the onset of spawning, was 1580 × 103. The significance of the sizes at first maturity, minimum legal length for capture, mesh selectivity data and closure of certain regions of estuaries to fishing for the management of the recreational and commercial fishery for A. butcheri is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009041525892
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    Salinity of surface waters in the Aral sea region (1999)
    Springer
    International journal of salt lake research 8 (1999), S. 293-306 
    Details
    ISSN: 1573-8590
    Keywords: Aral Sea ; salinity ; salinization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract An overview of recent changes in salinity in the surface waters of the Aral sea basin is given. Total dissolved salts (salinity) in most waters are higher than admissible values for drinking water, and ionic composition has changed with time. Salinity of the ‘Big Sea’ of the Aral was 48 g L−1 in 1998, but has decreased to below 21 g L−1 in the ‘Small Sea’ due to the building of a new dam between the two parts of the Aral Sea.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02442116
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    Applicability of Fatigue Life Prediction Method to Polymer Composites (1999)
    Springer
    Mechanics of time-dependent materials 3 (1999), S. 141-157 
    Details
    ISSN: 1573-2738
    Keywords: CFRP ; fatigue ; frequency ; stress ratio ; temperature ; viscoelasticity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract A prediction method of fatigue strength under an arbitraryfrequency, temperature, and stress ratio is proposed for polymercomposites and its validity is confirmed for the flexural fatiguestrength of satin-woven CFRP laminates. This method is based upon fourhypotheses: (a) same failure process under constant strain-rate (CSR),creep, and fatigue loadings, (b) same time-temperature superpositionprinciple for all failure strengths, (c) linear cumulative damage lawfor nondecreasing stress process, and (d) linear dependence of fatiguestrength upon stress ratio. This method was applied to the flexuralfatigue strength of various unidirectional CFRPs, and the verificationand limitations of this method were discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009873124095
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    Methodology for minimizing effects of temperature in monitoring with the acousto-ultrasonic technique (1999)
    Springer
    Experimental mechanics 39 (1999), S. 86-91 
    Details
    ISSN: 1741-2765
    Keywords: Acousto-ultrasonic ; damage monitoring ; temperature
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The acousto-ultrasonic (AU) technique can be a useful methodology for monitoring structures or mechanical components during endurance tests, fatigue tests or, in general, during the life of the components. To obtain reliable information about the failure and fatigue cracks at their earliest initiation stages and to follow their evolution regardless of any disturbance effects, refined experimental procedures and signal processing are needed. In particular, the effects of temperature variation cannot be entirely suppressed and are difficult to evaluate. This means that the results of the AU technique are not immediately interpretable and usable for monitoring structures. This paper describes some procedures aimed at minimizing the effects of disturbance on AU signals caused by temperature variation, allowing use of AU for monitoring over extensive periods of time or when the component is subjected to heating.
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    URL: http://dx.doi.org/10.1007/BF02331110
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    Thermoelastic contact problem of two rotating bodies with frictional heat generation in annular region (1998)
    Springer
    Archive of applied mechanics 68 (1998), S. 128-136 
    Details
    ISSN: 1432-0681
    Keywords: Key words frictional heating ; temperature ; contact pressure ; punch indentation ; thermoelasticity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Summary An axisymmetric contact problem with frictional heating is considered in which a parabolic annular punch is pressed into a plane surface and rotates about its axis of symmetry at constant speed. The problem is formulated in terms of one governing equation with unknown pressure. This equation is solved numerically. The change of the geometry of the contact region and pressure has been investigated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004190050150
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    Towards a Predictive Design Methodology Based on the Physical Modelling of the Fracture of Fiber Composites (1998)
    Springer
    Applied composite materials 5 (1998), S. 69-94 
    Details
    ISSN: 1573-4897
    Keywords: modelling ; notch strength ; damage ; fatigue ; environment ; temperature ; prediction ; design
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract A predictive design methodology based on modelling the fracture stress (notched tensile strength) and post-fatigue residual strength of laminated fiber composites is presented. The approach is based explicitly on the development of models of the physical processes by which damage accumulates at a notch-tip and the application of these models to cross-ply laminates for a variety of material systems, including thermosetting and thermoplastic matrices containing carbon, glass and Kevlar fiber reinforcements. The effects of temperature and humidity on composite fracture can also be examined in the context of this modelling strategy. A pre-requisite of the model is that it has to be calibrated for each material system by performing tensile tests on notched and unnotched cross-ply laminate. From this initial calibration, which takes relatively little time, it is possible to apply the model to a prediction of the dependence of fracture stress on notch size; to an understanding of the effects of laminate stacking sequence (within the same cross-ply family) on fracture stress; and to provide insight into the effects of thermal or load cycling history on fatigue damage-growth and residual or fatigue strength. The advantages and deficiencies of this modelling strategy are assessed, as well as the applicability of such a physical modelling approach to the predictive design and failure of composite materials in general.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008811721083
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    On the Spectral Decomposition of Geopotential and Temperature Fields in the Stratosphere (1998)
    Springer
    Studia geophysica et geodaetica 42 (1998), S. 147-158 
    Details
    ISSN: 1573-1626
    Keywords: stratosphere ; spectral decomposition ; geopotential ; temperature
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying , Geosciences , Physics
    Notes: Abstract The spectral structure of stratospheric fields (temperature and geopotential) is analyzed in terms of spherical harmonics in an effort to study the long-term behaviour of large-scale circulation patterns, as well as their connections to some extra-terrestrial effects. The daily meteorological data from the Free University Berlin (FUB) cover more or less the period 1976–1996 and are available for stratospheric levels of 50, 30 and 10 hPa. The analysis of the annual cycle of spherical harmonics is introduced, and changes of the principal wave components are compared with the changes in different sets of solar, geomagnetic and global circulation indices. This paper also deals with interannual variability with special emphasis on quasibiennial oscillations (QBO) and El Nino and Southern Oscillations (ENSO). Although this is a rather preliminary study, the decomposition of the stratospheric field into complex spherical harmonics seems to be a powerful technique in investigating and qualifying the response of the global atmospheric system to the changes in solar and geomagnetic activity, and in qualifying the relationships between large-scale circulation patterns and various oscillations such as QBO or ENSO, Using this technique, reasonable strong connections were found between wave numbers and interannual factors, and these connections were tentatively interpreted in terms of statistics. A very high degree of correlation was found for the four-trough shape of the polar vortex.
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    URL: http://dx.doi.org/10.1023/A:1023305020573
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    Changes of Ozone Content at Middle Latitudes During Forbush Decreases in Cosmic Rays (1998)
    Springer
    Studia geophysica et geodaetica 42 (1998), S. 521-532 
    Details
    ISSN: 1573-1626
    Keywords: stratospere ; troposphere ; solar-terrestrial disturbances ; odd nitrogen ; temperature ; atmospheric dynamics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying , Geosciences , Physics
    Notes: Abstract The variations of total ozone at Alma-Ata (43°N, 76 °E) and ozone profiles obtained by balloon sounding at Tateno (36°N, 140°E), Wallops Island (38°N, 75°W) and Cagliari (39°N, 9°E) in the periods of Forbush decreases (FD) in galactic cosmic rays have been analysed. A decrease of total ozone was observed in the initial stage of the FD and an increase 10–11 days later. The average total deviations calculated using the superposed epoch method for 9 FD events are equal to 30 D. U. in the positive and to −18 D. U. in the negative phase. The changes of average ozone profiles, associated with 26 FD events, are more significant in the lower stratosphere and upper troposphere. The decrease of the partial ozone pressure at a height of 12–15 km is about 30 υmb. These vertical variations of ozone coincide with the average changes of the respective temperature profiles. A cooling, on the average, of 3°C was observed at 12–15 km, and a heating of 4°C below this level.
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    URL: http://dx.doi.org/10.1023/A:1023301322428
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    Numerical prognosis for salinity profiles of future lakes in the opencast mine Merseburg-Ost (1998)
    Springer
    International journal of salt lake research 7 (1998), S. 235-260 
    Details
    ISSN: 1573-8590
    Keywords: groundwater ; Merseburg-Ost ; mine ; meromixis ; numerical model ; monimolimnion ; opencast ; physical limnology ; salinity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract Salt-laden groundwater inflows have formed monimolimnia in developing lakes of the abandoned opencast lignite mine Merseburg-Ost, Central Germany. Water-levels are still rising. To predict the future status of the lakes, two numerical models were developed. One was designed to predict groundwater flows, the second included limnophysical processes. The models were run in parallel and data exchange between them was performed every 1 to 10 years of model time. A trial of a 100-years prognosis was done. The results of surface salinity, mixing depth, and salinity profile are given. A sensitivity analysis yielded indications for the accuracy of the prediction.
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    URL: http://dx.doi.org/10.1023/A:1009097319823
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    Potential salinity limitations on nitrogen fixation in sediments from Mono Lake, California (1998)
    Springer
    International journal of salt lake research 7 (1998), S. 261-274 
    Details
    ISSN: 1573-8590
    Keywords: cyanobacteria ; lake management ; Mono Lake ; nitrogen fixation ; salinity ; saline lakes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract Mono Lake is a hypersaline alkaline lake in the high altitude Great Basin desert of eastern California. Algal productivity of the lake is nitrogen-limited, and a contributing source is derived from benthic nitrogen fixation. Lake level and salinity have fluctuated with natural climatic variations but have also been affected by the diversion of tributary streams. This research examines the influence of varied salinity and lake level on the potential for benthic nitrogen fixation in Mono Lake. A sediment-surface microbial mat community was exposed directly, and in acclimated cultures, to a range of Mono Lake salinities under anaerobic incubations and the activity of nitrogenase assayed by acetylene reduction. Activity was stimulated in light, but also occurred in darkness. Over an experimental salinity range from 50 to 150 g L−1 TDS, nitrogenase activity was reduced by 90 per cent, with the activity persisting at the highest salinity being attributable to dark fixation alone. Between a salinity of 50 g L−1, occurring in Mono Lake over 50 years ago, and 100 g L−1, nitrogenase activity was reduced by nearly half. Changes in the area of the littoral zone at varied lake levels also affect the total amount of potential benthic nitrogen fixation in the lake. An accounting of yearly inputs of nitrogen to Mono Lake suggests N2-fixation could contribute as much as 76–81 percent of the total. Inhibition of nitrogen fixation rates by increased salinity could limit the long-term nutrient supply and benthic primary productivity of this ecosystem.
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    URL: http://dx.doi.org/10.1007/BF02441878
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    The relationship between electrical conductivity and selected macroinvertebrate communities in four river systems of south-west Victoria, Australia (1998)
    Springer
    International journal of salt lake research 7 (1998), S. 153-170 
    Details
    ISSN: 1573-8590
    Keywords: confounding parameters ; nutrients ; salinity ; survey design
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract In order to relate macroinvertebrate fauna to electrical conductivity (EC), a survey of selected orders of macroinvertebrates was conducted in the Glenelg, Hopkins, Merri and Barwon River Catchments in south-west Victoria, Australia. The survey consisted of sampling 21 paired sites at confluences of streams. There was little difference between the in-stream habitat but there was a range of differences in EC between each of the paired sites. The dissimilarity of macroinvertebrate fauna between the paired sites was compared to the proportional difference in EC and other water quality variables (dissolved oxygen, water temperature, pH, NO2−N, NO3−N, PO4 and turbidity). This allowed the elimination of EC being confounded with geographical scale parameters and took into account other water quality parameters that may be confounded with EC. A positive relationship was found between the dissimilarity of the fauna at each of the two paired sites and the proportional difference in EC. No such relationship was found for any other measured water quality variable. The results of this survey show that macroinvertebrate community structure is associated with EC of the river systems investigated after eliminating large scale geographical patterns, in-stream habitat and the measured water quality parameters.
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    URL: http://dx.doi.org/10.1007/BF02441884
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    Potential salinity limitations on nitrogen fixation in sediments from Mono Lake, California (1998)
    Springer
    International journal of salt lake research 7 (1998), S. 261-274 
    Details
    ISSN: 1573-8590
    Keywords: cyanobacteria ; lake management ; Mono Lake〉/kwd〉 ; nitrogen fixation ; salinity ; saline lakes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract Mono Lake is a hypersaline alkaline lake in the high altitude Great Basin desert of eastern California. Algal productivity of the lake is nitrogen-limited, and a contributing source is derived from benthic nitrogen fixation. Lake level and salinity have fluctuated with natural climatic variations but have also been affected by the diversion of tributary streams. This research examines the influence of varied salinity and lake level on the potential for benthic nitrogen fixation in Mono Lake. A sediment-surface microbial mat community was exposed directly, and in acclimated cultures, to a range of Mono Lake salinities under anaerobic incubations and the activity of nitrogenase assayed by acetylene reduction. Activity was stimulated in light, but also occurred in darkness. Over an experimental salinity range from 50 to 150 g L-1 TDS, nitrogenase activity was reduced by 90 per crnt, with the activity persisting at the highest salinity being attributable to dark fixation alone. Between a salinity of 50 g L-1, occurring in Mono Lake over 50 years ago, and 100 g L-1, nitrogenase activity was reduced by nearly half. Changes in the area of the littoral zone at varied lake levels also affect the total amount of potential benthic nitrogen fixation in the lake. An accounting of yearly inputs of nitrogen to Mono Lake suggests N2-fixation could contribute as much as 76–81 percent of the total. Inhibition of nitrogen fixation rates by increased salinity could limit the long-term nutrient supply and benthic primary productivity of this ecosystem.
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    URL: http://dx.doi.org/10.1023/A:1009001514449
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    Numerical prognosis for salinity profiles of future lakes in the opencast mine Merseburg-Ost (1998)
    Springer
    International journal of salt lake research 7 (1998), S. 235-260 
    Details
    ISSN: 1573-8590
    Keywords: groundwater ; Merseburg-Ost ; mine ; meromixis ; numerical model ; monimolimnion ; opencast ; physical limnology ; salinity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract Salt-laden groundwater inflows have formed monimolimnia in developing lakes of the abandoned opencast lignite mine Merseburg-Ost, Central Germany. Water-levels are still rising. To predict the future status of the lakes, two numerical models were developed. One was designed to predict groundwater flows, the second included limnophysical processes. The models were run in parallel and data exchange between them was performed every 1 to 10 years of model time. A trial of a 100-years prognosis was done. The results of surface salinity, mixing depth, and salinity profile are given. A sensitivity analysis yielded indications for the accuracy of the prediction.
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    URL: http://dx.doi.org/10.1007/BF02441877
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    Is salinity the only water quality parameter affected when saline water is disposed in rivers? (1998)
    Springer
    International journal of salt lake research 7 (1998), S. 285-299 
    Details
    ISSN: 1573-8590
    Keywords: nutrients ; salinity ; water quality
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract The effect of saline lake water disposal from the Lough Calvert Drainage Scheme on water quality of the Barwon River, in south west Victoria, Australia, was investigated. The Scheme is used to regulate the levels of several saline lakes outside the Barwon's catchment. This study found that the disposal of saline lake water was associated with increased total phosphorus, PO4, TKN, suspended solids, electrical conductivity and stream discharge and lower NOx in the Barwon River. Thus, when disposing of saline water, factors other than salinity should be considered in order to prevent an impact on the aquatic environment. At present this is generally not done. The results are discussed with reference to the effects of saline water disposal on aquatic biota and how the effect of saline lake water disposal on water quality may differ from the disposal of saline groundwater.
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    URL: http://dx.doi.org/10.1023/A:1009023515649
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    Is salinity the only water quality parameter affected when saline water is disposed in rivers? (1998)
    Springer
    International journal of salt lake research 7 (1998), S. 285-300 
    Details
    ISSN: 1573-8590
    Keywords: nutrients ; salinity ; water quality
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract The effect of saline lake water disposal from the Lough Calvert Drainage Scheme on water quality of the Barwon River, in south west Victoria, Australia, was investigated. The Scheme is used to regulate the levels of several saline lakes outside the Barwon's catchment. This study found that the disposal of saline lake water was associated with increased total phosphorus, PO4, TKN, suspended solids, electrical conductivity and stream discharge and lower NOx in the Barwon River. Thus, when disposing of saline water, factors other than salinity should be considered in order to prevent an impact on the aquatic environment. At present this is generally not done. The results are discussed with reference to the effects of saline water disposal on aquatic biota and how the effect of saline lake water disposal on water quality may differ from the disposal of saline groundwater.
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    URL: http://dx.doi.org/10.1007/BF02442141
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    The relationship between electrical conductivity and selected macroinvertebrate communities in four river systems of south-west Victoria, Australia (1998)
    Springer
    International journal of salt lake research 7 (1998), S. 153-170 
    Details
    ISSN: 1573-8590
    Keywords: confounding parameters ; nutrients ; salinity ; survey design
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract In order to relate macroinvertebrate fauna to electrical conductivity (EC), a survey of selected orders of macroinvertebrates was conducted in the Glenelg, Hopkins, Merri and Barwon River Catchments in south-west Victoria, Australia. The survey consisted of sampling 21 paired sites at confluences of streams. There was little difference between the in-stream habitat but there was a range of differences in EC between each of the paired sites. The dissimilarity of macroinvertebrate fauna between the paired sites was compared to the proportional difference in EC and other water quality variables (dissolved oxygen, water temperature, pH, NO2-N, NO3-N, PO4 and turbidity). This allowed the elimination of EC being confounded with geographical scale parameters and took into account other water quality parameters that may be confounded with EC. A positive relationship was found between the dissimilarity of the fauna at each of the two paired sites and the proportional difference in EC. No such relationship was found for any other measured water quality variable. The results of this survey show that macroinvertebrate community structure is associated with EC of the river systems investigated after eliminating large scale geographical patterns, in-stream habitat and the measured water quality parameters.
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    URL: http://dx.doi.org/10.1023/A:1009019404720
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    Magnetometric Method of Investigating Fire Sites (1997)
    Springer
    Fire technology 33 (1997), S. 195-213 
    Details
    ISSN: 1572-8099
    Keywords: point of fire origin ; fire ; temperature ; plaster ; concrete ; thermal ; damage ; biotite ; magnetization ; susceptibility ; N-rays ; P-rays ; X-rays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying
    Notes: Abstract Magnetic susceptibility (MS) measurements were taken to determine fire exposure patterns on noncombustible structural members and compartment boundaries. These measurements led on-site fire investigators to the cause of combustion and the point of fire origin. Thermal damage to walls and to ceilings was estimated quantitatively by measuring MS and two-valent Fe ion concentration in building materials such as concrete and plaster. It was shown that these effects are preconditioned by thermochemical transformations in the mineral biotite, which is present as a component of common building materials. For the first time, the effect of a substantial and irreversible increase in biotite magnetization exposed to powerful flows of N- and P-rays was found. It is hoped that the presence of this “magnetic trace” of radiation in building materials will allow investigators to use the magnetometric method at nuclear power plant catastrophes such as that in Chernobyl. It was also shown that the influence of N- and P-rays on biotite's magnetic properties greatly differs from the thermal influence on biotite.
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    URL: http://dx.doi.org/10.1023/A:1015363605037
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    Effect of time-dependent speed on frictional heat generation and wear in transient axisymmetrical contact of sliding (1997)
    Springer
    Archive of applied mechanics 67 (1997), S. 331-338 
    Details
    ISSN: 1432-0681
    Keywords: Key words frictional heating ; wear ; contact pressure ; temperature ; brake system
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Summary A transient contact problem with frictional heating and wear for two nonuniform sliding half-spaces is considered. One of the two half-spaces is assumed to be slightly curved to give a Hertzian initial pressure distribution: the other is a rigid nonconductor. Under the assumption that the contact pressure distribution could be described by Hertz formulas during all the process of interaction, the problem is formulated in terms of one integral equation of Volterra type with unknown radius of contact area. A numerical solution of this equation is obtained using a piecewise-constant presentation of an unknown function. The influence of operating parameters on the contact temperature and the radius of the contact area is studied.
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    URL: http://dx.doi.org/10.1007/s004190050121
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    Variability in biomarkers of different saline basins in China (1997)
    Springer
    International journal of salt lake research 6 (1997), S. 25-53 
    Details
    ISSN: 1573-8590
    Keywords: biomarker ; palaeoenvironment ; salinity ; salt lake ; sulfur
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract 42 samples (sediments and crude oils) from 5 differentsaline/hypersaline basins of China were examined using variety ofgeochemical techniques. A pronounced even over odd distribution of n-alkanesis observed for the Ejinur, Jianghan samples. Abundance of isoprenoidalkanes, dominated by phytane (C20 up to 20 per cent inEOM), and C25 and C30 components isanother outstanding feature of these studied lacustrine hypersalinesettings, indicating important contributuions from archaebacteria.Gammacerane is a major component of some Eocene Jianghan samples andCretaceous Taian sediments. Absolute concentration of phytane andgammacerane appears to be linearly related to chlorine and residual(reduced) sulfur contents of sediments from Jianghan basin, suggestingsulfur incoporation might have played an important role in the enhacement ofthese biomarkers in the anoxic hypersaline, alkaline settings. Wide range oforganic sulfur compounds in immature samples of Jianghan Basin reflects asignificant pathway for sulfur incorporation under hypersaline, extremelyanoxic/reducing conditions, although for some structures a direct originfrom some sulfur archaebacteria can not be excluded. Brackish salt marshsediment and oil from Lenghu depression contain abundant lupane, strong OEPin n-alkane series, and predominance of C29 steranes,suggesting a markedly input from vascular higher plants. The marginal marineevaporate sediments from the hypersaline Triassic Yangtze Platform is uniquefor its predominant, complete series of isoprenoid alkanes up toC36 (abundant) and C40 (trace). Theselong-chain isoprenoids are probably derived from phytoplanktons in additionto archaebacteria. The marked difference in biomarker distributions from thevarious suites of samples support that application of these biomarkers tohelp effectively characterize different saline basins. The molecularvariation is, however, not only due to their discrepancy in biologicalsources, but also the extension of sulfate reduction and the availability ofmetal ions during early diagenesis.
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    Variability in biomarkers of different saline basins in China (1997)
    Springer
    International journal of salt lake research 6 (1997), S. 25-53 
    Details
    ISSN: 1573-8590
    Keywords: biomarker ; palaeoenvironment ; salinity ; salt lake ; sulfur
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract 42 samples (sediments and crude oils) from 5 different saline/hypersaline basins of China were examined using variety of geochemical techniques. A pronounced even over odd distribution ofn-alkanes is observed for the Ejinur, Jianghan samples. Abundance of isoprenoid alkanes, dominated by phytane (C20 up to 20 per cent in EOM), and C25 and C30 components is another outstanding feature of these studied lacustrine hypersaline settings, indicating important contributuions from archaebacteria. Gammacerane is a major component of some Eocene Jiangham samples and Cretaceous Taian sediments. Absolute concentration of phytane and gammacerane appears to be linearly related to chlorine and residual (reduced) sulfur contents of sediments from Jianghan basin, suggesting sulfur incoporation might have played an important role in the enhacement of these biomarkers in the anoxic hypersaline, alkaline settings. Wide range of organic sulfur compounds in immature samples of Jianghan Basin reflects a significant pathway for sulfur incorporation under hypersaline, extremely anoxic/reducing conditions, although for some structures a direct origin from some sulfur archaebacteria can not be excluded. Brackish salt marsh sediment and oil from Lenghu depression contain abundant lupane, strong OEP inn-alkane series, and predominance of C29 steranes, suggesting a markedly input from vascular higher plants. The marginal marine evaporate sediments from the hypersaline Triassic Yangtze Platform is unique for its predominant, complete series of isoprenoid alkanes up to C36 (abundant) and C40 (trace). These long-chain isoprenoids are probably derived from phytoplanktons in addition to archaebacteria. The marked difference in biomarker distributions from the various suites of samples support that application of these biomarkers to help effectively characterize different saline basins. The molecular variation is, however, not only due to their discrepancy in biological sources, but also the extension of sulfate reduction and the availability of metal ions during early diagenesis.
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    URL: http://dx.doi.org/10.1007/BF02441867
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    The analysis of nitrate in highly saline waters (1997)
    Springer
    International journal of salt lake research 6 (1997), S. 269-278 
    Details
    ISSN: 1573-8590
    Keywords: nitrate analysis ; salt effect ; salinity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract The analysis of nitrate in seawater and hypersalinewaters should take account of a significant “salteffect”. Procedures developed for fresh water andmarine waters must be applied cautiously to highlysaline waters. The most widely used standard methodfor the determination of nitrate-nitrogen (NO3-N)in fresh and marine waters involves the quantitativereduction of nitrate by the Cd column techniquefollowed by colorimetric procedures. In our study,three approaches to estimate NO3-N in highlysaline waters were examined. The first involveddilution. This approach overcame the salt effect butdilution limited the detection of low concentrationsof nitrate in highly saline waters. The secondinvolved the use of standard nitrate solutions insaline water. This method is not recommended becauseof nitrate impurities in AR grade salts. The third-and preferred approach-involved the use of standardadditions. “Spikes” of a known volume of NO3-Nstandard solution were added to natural saline waters. Nitrate values estimated by the standard additionmethod were used to calculate an equation for salterror correction at different salinities applicable towaters with the same relative ionic composition asseawater. This could then be used to correct nitratedeterminations in highly saline waters where standardsmade in distilled water were used for calibration.Many previously published data for NO3-N insaline water used methods of analysis which do nottake account of salt error and are therefore probablyin error.
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    URL: http://dx.doi.org/10.1023/A:1009008120817
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    The analysis of nitrate in highly saline waters (1997)
    Springer
    International journal of salt lake research 6 (1997), S. 269-278 
    Details
    ISSN: 1573-8590
    Keywords: nitrate analysis ; salt effect ; salinity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract The analysis of nitrate in seawater and hypersaline waters should take account of a significant “salt effect”. Procedures developed for fresh water and marine waters must be applied cautiously to highly saline waters. The most widely used standard method for the determination of nitrate-nitrogen (NO3-N) in fresh and marine waters involves the quantitative reduction of nitrate by the Cd column technique followed by colorimetric procedures. In our study, three approaches to estimate NO3-N in highly saline waters were examined. The first involved dilution. This approach overcame the salt effect but dilution limited the detection of low concentrations of nitrate in highly saline waters. The second involved the use of standard nitrate solutions in saline water. This method is not recommended because of nitrate impurities in AR grade salts. The third- and preferred approach-involved the use of standard additions. “Spikes” of a known volume of NO3-N standard solution were added to natural saline waters. Nitrate values estimated by the stadard addition method were used to calculate an equation for salt error correction at different salinities applicable to waters with the same relative ionic composition as seawater. This could then be used to correct nitrate determinations in highly saline waters where standards made in distilled water were used for calibration. Many previously published data for NO3-N in saline water used methods of analysis which do not take account of salt error and are therefore probably in error.
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    URL: http://dx.doi.org/10.1007/BF02449929
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    Midge-and diatom-based palaeosalinity reconstructions for Mahoney Lake, Okanagan Valley, British Columbia, Canada (1997)
    Springer
    International journal of salt lake research 6 (1997), S. 249-267 
    Details
    ISSN: 1573-8590
    Keywords: Chironanidae ; diatoms ; palaeoclimate ; palaeolimnology ; palaeoecology ; palaeosalinity ; salinity ; postglacial ; climate change
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract Salinity fluctuations in lakes of semi-arid regions have long been recognised as indicators of palaeoclimatic change, and have provided a valuable line of evidence in palaeo-climatic reconstruction. In the present study, fossil remains of diatoms and midges were used to reconstruct salinity changes at Mahoney Lake from the early postglacial, through the early, mid and late Holocene. A transition from midges typical of a freshwater community (Protanypus, Sergentia, Heterotrissocladius, Cladopelma, Dicrotendipes) during the early postglacial, to those indicative of saline environments (Cricotopus/Orthocladius, Tanypus) occurred in the early Holocene. The midge-inferred salinity values reflected the shift from freshwater (0.031 g/L) immediately after deglaciation, to saline water (2.4 to 55.2 g/L) in subsequent periods. A less saline period was found to have occurred after 1000 yr BP, suggesting a cooler or wetter period. The diatom record indicates similar trends, with freshwater taxa (e.g.,Cyclotella bodanica var. aff.lemanica) dominating near the bottom of the core. Diatom-inferred salinities indicate that saline conditions (about 30 g/L) prevailed throughout subsequent Holocene time, although relatively fresh conditions are indicated following deposition of the Mazama Ash, and from about 1500 yr BP until the present day. Midge and diatom-inferred salinity reconstructions for Mahoney Lake compare favorably with each other, and with climate trends inferred from earlier palynological evidence. The palaeosalinity record thus contributes new data relevant to past climatic conditions, in a region where little data have previously been collected.
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    URL: http://dx.doi.org/10.1007/BF02449928
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    Midge- and diatom-based palaeosalinity reconstructions for Mahoney Lake, Okanagan Valley, British Columbia, Canada (1997)
    Springer
    International journal of salt lake research 6 (1997), S. 249-267 
    Details
    ISSN: 1573-8590
    Keywords: Chironanidae ; diatoms ; palaeoclimate ; palaeolimnology ; palaeoecology ; palaeosalinity ; salinity ; postglacial ; climate change
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract Salinity fluctuations in lakes of semi-arid regions have long beenrecognised as indicators of palaeoclimatic change, and have provided avaluable line of evidence in palaeoclimatic reconstruction. In the presentstudy, fossil remains of diatoms and midges were used to reconstructsalinity changes at Mahoney Lake from the early postglacial, through theearly, mid and late Holocene. A transition from midges typical of afreshwater community (Protanypus, Sergentia, Heterotrissocladius,Cladopelma, Dicrotendipes) during the early postglacial, to those indicativeof saline environments (Cricotopus/Orthocladius, Tanypus) occurred in theearly Holocene. The midge-inferred salinity values reflected the shift fromfreshwater (0.031 g/L) immediately after deglaciation, to saline water (2.4to 55.2 g/L) in subsequent periods. A less saline period was found to haveoccurred after 1000 yr BP, suggesting a cooler or wetter period. The diatomrecord indicates similar trends, with freshwater taxa (e.g., Cyclotellabodanica var. aff. lemanica) dominating near the bottom of the core.Diatom-inferred salinities indicate that saline conditions (about 30 g/L)prevailed throughout subsequent Holocene time, although relatively freshconditions are indicated following deposition of the Mazama Ash, and fromabout 1500 yr BP until the present day. Midge and diatom-inferred salinityreconstructions for Mahoney Lake compare favorably with each other, and withclimate trends inferred from earlier palynological evidence. Thepalaeosalinity record thus contributes new data relevant to past climaticconditions, in a region where little data have previously been collected.
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    URL: http://dx.doi.org/10.1023/A:1009056003978
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    Micellization of triblock copoly(ethyleneoxide/tetrahydrofuran/ethylene oxide) (1997)
    Springer
    Colloid & polymer science 275 (1997), S. 467-473 
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    ISSN: 1435-1536
    Keywords: Key words Block copolymers ; micelle ; temperature
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract  The association behaviour of triblock copoly(ethylene oxide/tetrahydrofuran/ethylene oxide), in particular E100T27E100, in aqueous solutions has been investigated by means of static and dynamic light scattering, nuclear magnetic reso-nance (NMR) and surface tension techniques. On raising the polymer concentration at room temperature, the copolymer aggregates to form micelles with an aggregation number of about 105 (R G, mic≈15 nm and R H, mic≈13 nm, as revealed by light scattering and FT-PGSE NMR measurements, respectively). The micelles are kinetically quite stable, the micellar lifetime is shown to be more than 1 h. The residence time of a single unimer in a micelle is more than 140 ms. The apparent radius of gyration R G, mic is fairly independent of concentration, but large effects are observed on varying the temperature. Raising the temperature initially results in an increase of the apparent micellar size, followed by a maximum at an intermediate temperature (≈45 °C). At higher temperatures a contraction of the micelles is observed. The shape of the micelles also appear to vary in this temperature interval. The interactions responsible for these phenomena are discussed in terms of, e.g., the temperature-dependent solubility of the alkylene oxide segments in water and polydispersity effects.
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    Temperature effect on shear induced transition in surfactant solution (1997)
    Springer
    Colloid & polymer science 105 (1997), S. 322-325 
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    ISSN: 1435-1536
    Keywords: Rheology ; surfactant solutions ; micelles ; phase transition ; temperature
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Aqueous solutions of cationic surfactant with binding counterions exhibit a transition under shear. In this paper the steady shear properties of semidilute aqueous micellar solutions (cetylpyridinium chloride and sodium salicylate in brine) are presented as a function of concentration and temperature. The shear thinning behavior of this system could be described by the Carreau model at low shear rate and by a power law at higher shear rate. The temperature dependence of the zero shear viscosity follows an Arrhenius relationship. The critical shear rate at which the viscosity departs from its zero shear value is found to increase with temperature indicating the influence of this parameter on transition.
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    Comparisons between the ichthyofaunas of a temperate lagoonal-like estuary and the embayment into which that estuary discharges (1996)
    Springer
    International journal of salt lake research 5 (1996), S. 337-358 
    Details
    ISSN: 1573-8590
    Keywords: estuary ; fish fauna ; marine embayment ; protection ; salinity ; shallow waters
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract Leschenault Estuary consists of a large lagoonal-like water body, which opens into Koombana Bay through a short and deep entrance channel at its southern end. Since the only major tributary discharges into the estuary opposite the entrance channel, much of the freshwater discharge in the winter passes directly out to sea. Consequently, during the year of the present study, the mean monthly salinities in the main body of the estuary remained above 20 per mil. This presumably accounts for the fact that the ichthyofaunal composition in the shallows of the estuary did not undergo the type of marked changes that are exhibited in other south-western Australian estuaries, in which salinities often fall below 10 per mil in winter. Despite the maintenance of high salinities in Leschenault Estuary and a close proximity to Koombana Bay, the estuary contained a far greater density and markedly different species composition of fish than that found in that marine embayment. This difference reflected, in part, the high abundance in Leschenault Estuary of some species whose entire life cycle is confined to estuaries,e.g. the atherinidsAtherinosoma elongata andLeptatherina wallacei and the gobiesPseudogobius olorum andAfurcagobius suppositus, and the fact that the juveniles of several marine species,e.g. Hyperlophus vittatus, Sillaginodes punctata, Mugil cephalus andGymnapistes marmoratus were also largely or entirely restricted to the estuary. In contrast,Lesueurina platycephala, which was by far the most abundant species in Koombana Bay, was absent in the estuary. Furthermore, the relatively protected region of Koombana Bay contained a greater density and different composition of fish than the more exposed region of this embayment. This reflected the greater use that was made of the protected region as a nursery area by certain marine species,e.g. Aldrichetta forsten andSillago bassensis. Our data, when taken in conjunction with those collected on the fish fauna in other south-western Australian estuaries, demonstrate that, within this geographical region, some fish species are specifically adapted to the estuarine environment, and that certain marine species apparently have a strong preference for using the highly protected and productive waters of this type of environment as a nursery area.
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    Aquatic macrophyte distribution in Lake Manzala, Egypt (1996)
    Springer
    International journal of salt lake research 5 (1996), S. 221-239 
    Details
    ISSN: 1573-8590
    Keywords: aquatic macrophytes ; ecological distribution ; Lake Manzala ; ordination ; salinity ; TWINSPAN ; water depth
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract The macrophyte distribution of Lake Manzala is described in relation to water depth, salinity, dissolved oxygen, pH, Cl−, NO 3 − and PO 4 3− . Changes in species composition of macrophytes are visualised by means of multivariate analysis. The TWINSPAN classification and CANOCO ordination programs (DCA & CCA) were used to analyse the data set. The classification of 100 stands revealed 8 vegetation groups which indicated eleven dominant communities. These arePhragmites australis, Typha domingensis, Scirpus maritimus, Echinochloa stagnina and Ludwigia stolonifera as emergent hydrophytes;Eichhornia crassipes andAzolla filiculoides as floating hydrophytes. The dominant submerged hydrophytes arePotamogeton pectinatus, Najas armata, Ceratophyllum demersum andRuppia maritima. The northern part of the lake with low depth and relatively high salinity has low species diversity (mainly emergent species). Species diversity increases with decreasing salinity and increasing eutrophication near the mouths of the drains in the western and southern parts of the lake. The recent changes in species distribution can be attributed to the effects of salinity, water depth and drainage water. A checklist of macrophytes in the lake is appended.
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    URL: http://dx.doi.org/10.1007/BF01997138
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    Dynamic thermoelastic effects for half-planes and half-spaces with nearly-planar surfaces (1996)
    Springer
    Journal of elasticity 44 (1996), S. 229-254 
    Details
    ISSN: 1573-2681
    Keywords: thermoelasticity ; surface ; nearly-planar ; dynamic ; temperature
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract The effects of non-planarity on the dynamic surface temperature changes induced for plane-strain and 3D problems on the nearly-planar surfaces of, respectively, coupled thermoelastic half-planes and half-spaces by surface heat fluxes are treated. The nearly-planar nature of the surfaces allows the problem solutions to be written, following a standard perturbation scheme, as series expansions in a dimensionless surface contour amplitude parameter. The first, or zero-order, terms represent the ideal (planar) surface solutions, while the second, or first-order, terms represent corrections for non-planarity. Because the characteristic thermoelastic time is of O(10−7)μs, large-time asymptotic forms of the exact integral transform solutions can be used. These can be inverted exactly and used in Green's function operations to yield analytic, or integrals of analytic, expressions. Two types of thermal loading for the half-plane and yet a third type of thermal loading for the half-space are considered. Comparison of the zero- and first-order surface temperature changes for each case indicate that non-planarity gives rise for large times to changes in surface regions beyond those predicted by an ideal surface analysis. Moreover, the magnitudes of these changes can be more significant than the ideal surface results.
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    URL: http://dx.doi.org/10.1007/BF00042134
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    Effect of temperature on the wear of an electroless nickel coating under lubricated reciprocating sliding conditions (1996)
    Springer
    Tribology letters 2 (1996), S. 263-272 
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    ISSN: 1573-2711
    Keywords: wear ; temperature ; coatings ; Ni-P coatings ; lubrication
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The effect of temperature on the wear of as-deposited electroless Ni-P coating under lubricated reciprocating sliding conditions has been investigated using the ball-on-block test method. It was shown that the temperature increase from 25 to 100°C reduces the lubricated wear of EN coatings, especially at high loads. The wear mechanism has also changed as the temperature rises from 25 to 100°C. X-ray mapping and EDS analyses have shown that there are more sulfur and phosphorus on the wear track at high temperature which may be responsible for reduced friction and the wear of the coating.
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    URL: http://dx.doi.org/10.1007/BF00173132
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    Effect of melting on the excitation of surface acoustic wave pulses by UV nanosecond laser pulses in silicon (1995)
    Springer
    Applied physics 61 (1995), S. 285-298 
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    ISSN: 1432-0630
    Keywords: 42.55 ; 43.00 ; 62.00 ; 65.00 ; 68.00
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract The influence of melting on the excitation of Surface Acoustic Wave (SAW) pulses in silicon is studied both theoretically and experimentally. The developed theory of Rayleigh-type SAW laser-induced thermoelastic excitation in a structure composed of a liquid layer on a solid substrate predicts that the SAW is predominantly generated in the solid phase due to the absence of shear rigidity in a liquid. The characteristic changes in the SAW pulse shape as well as the saturation and even the decrease of the SAW pulse amplitude observed above the melting threshold are explained theoretically to be a result of the decrease of the heat flux into the solid phase as well as due to the decrease of the volume of the solid phase caused by melting. Although the heat flux into the solid phase is decreased both as a consequence of the reflectivity increase and the additional energy losses (latent heat of melting) at the phase transition, it is demonstrated that the influence of reflectivity changes on the SAW pulse is negligible in comparison with the effect of melt-front motion. For laser pulses of 7 ns duration at 355 nm, the threshold value of laser fluence for meltingF m=0.23±0.04 J/cm2 and for the ablationF a=1.3±0.2 J/cm2 were determined experimentally as the points of characteristic changes in the observed SAW pulses.
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    Characterization of a twin-torch transferred dc arc (1995)
    Springer
    Plasma chemistry and plasma processing 15 (1995), S. 309-331 
    Details
    ISSN: 1572-8986
    Keywords: Transferred arc ; voltage-current characteristic ; inhomogeneous plasma ; optical emission spectroscopy ; electron density ; temperature ; spatial distribution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Technology
    Notes: Abstract The results of a twin-torch transferred de arc .study are presented. The arc system consists of two torches of opposite polarity, and a coupling zone of plasma jets located between them. The torch configuration increases the system reliability and efficiency during material plasma processing. The results of the study present data for the voltage-current characteristics, general behavior of the twin-torch arc, and spatial distribution of the plasma parameters. The plasma parameters have been measured using optical emission spectroscopy for a 200 A (20 k W) do arc, at atmospheric pressure, with argon and nitrogen introduced as plasma forming gases into the anode and the cathode units, respectively. The measurement technique used has allowed the determination of local electron density and temperature values in an inhomogeneous plasma volume having no axial sysmmetry. The data obtained illustrate the novel features of the twin-torch transfrred do arc for its applications in plasma processing.
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    URL: http://dx.doi.org/10.1007/BF01459701
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    Hydrogen/argon plasma jet with methane addition (1995)
    Springer
    Plasma chemistry and plasma processing 15 (1995), S. 333-351 
    Details
    ISSN: 1572-8986
    Keywords: Hydrogen/argon plasma ; methane ; do arc jet ; atmospheric pressure ; optical emission spectroscopy ; temperature ; density ; spatial distribution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Technology
    Notes: Abstract Spatial distributions of plasma parameters are presented for a H2/Ar plasma jet with addition of methane. The plasma has been generated at atmospheric pressure by a 200 A (20 kW) nontransferred do arc. Optical emission spectroscopy has been used for the measurements assuming the plasma jet to be optically thin and to have an axial symmetry. Local spectral ernissivity values have been evaluated using a routine Abel inversion procedure. Half- width and emissivity of Hβ spectral line have been measured to determine the electron density and temperature of the plasma. The densities of excited C, CH radicals have been evaluated from the absolute emissivities of relevant molecular emission bands measured in limited spectral intervals in the visible spectrum. The emissivity ratios have been used to fund rotational and vibrational temperatures. The results supply information on methane decomposition and the behavior of molecular radicals in close-to-thermal plasma jets.
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    URL: http://dx.doi.org/10.1007/BF01459702
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    PGSE-NMR studies of solvent diffusion in poly(N-isopropylacrylamide) colloidal microgels (1995)
    Springer
    Colloid & polymer science 273 (1995), S. 405-411 
    Details
    ISSN: 1435-1536
    Keywords: NMR diffusion ; solvent diffusion ; hydrogels ; microgels ; temperature
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The solvent self-diffusion coefficient has been studied in thermoshrinking poly(N-isopropyl acrylamide) microgel dispersions by the pulsed-gradient spin-echo PGSE-NMR technique, as a function of temperature and mass fraction. After suitable corrections for the temperature, the H2O/D2O ratio and the relative volume fractions, all the self-diffusion data obtained over a temperature range of approximately 40 °C and mass fraction (2–12 % wt/wt) could be superimposed with the volume fraction as the universal factor. The observed reduction in the solvent self-diffusion coefficient with volume fraction was greater than that predicted by simple obstruction theory. After correction for-, and the subsequent removal of the obstruction effect, the diffusion of the solvent through the core of the particle is elucidated. As found for other polymer-solvent systems, there were no specific binding effects. The diffusion of the solvent in these dispersions over such temperature and mass fraction ranges could be rationalised assuming a constant solvent self-diffusion coefficient in the core of the particles.
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    Evaluation of climatic change through harmonic analysis (1994)
    Springer
    Natural hazards 9 (1994), S. 5-16 
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    ISSN: 1573-0840
    Keywords: Fourier transform ; maximum entropy spectral analysis ; precipitation ; temperature ; climatic change
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Geography , Geosciences
    Notes: Abstract In the present work, a precipitation and temperature series from Barcelona (Spain) are analysed in order to detect the possible existence of climatic changes or cycles. The analysis is carried out both from the temporal and spectral standpoints. The techniques used range from the classical periodogram and Blackman-Tukey method through to the Maximum Entropy method. The results do not show the existence of climatic cycles, though they do show a clear tendency toward increased precipitation and decreased temperature, since the last years of series.
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    Femtosecond excimer-laser-induced structure formation on polymers (1994)
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    Applied physics 59 (1994), S. 289-293 
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    ISSN: 1432-0630
    Keywords: 42.55 ; 81.40 ; 82.65
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract Structure formation upon 500 fs 248 nm KrF-laser irradiation of PolyEthylene Terephthalate (PET) and PolyImide (PI) has been investigated. The results obtained with fs pulses have been compared to those with ns pulses.
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    URL: http://dx.doi.org/10.1007/BF00348232
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    Definition and measurement of salinity in salt lakes (1994)
    Springer
    International journal of salt lake research 3 (1994), S. 53-63 
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    ISSN: 1573-8590
    Keywords: salinity ; athalassic ; salt lakes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract Salinity is the most important chemical attribute of athalassic salt lakes. Even so, some confusion persists of what ‘salinity’ means and how to measure it. For sal lakes, salinity is best defined as the sum total of all ion concentrations, or total ion concentration. Ideally, it is recommended that salinities be expressed on a mass per mass basis and as ppt (parts per thousand). Direct measurements of salinity can only be derived from full ionic analyses. Indirect measurements can be derived by determinations of density, conductivity, freezing point depression and total dissolved solids or matter.
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    Air microwave-induced plasma: Detection of NO in the post-discharge using an ArF laser (1993)
    Springer
    Plasma chemistry and plasma processing 13 (1993), S. 351-364 
    Details
    ISSN: 1572-8986
    Keywords: Air microwave plasma ; laser-induced fluorescence ; temperature ; nitrogen monoxide density
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Technology
    Notes: Abstract ArF laser-induced fluorescence (LIF) spectroscopy was applied to the investigation of the density of NO achieved in the post-discharge of an N2-O2 microwave-induced plasma (2450 MHz). The fluorescence spectrum provides a determination of NO vibrational temperature downstream the discharge. Absolute concentration profiles were determined in the low-temperature region of the post-discharge.
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    URL: http://dx.doi.org/10.1007/BF01466049
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    EPR and optical spectroscopy of Cr3+ ions in Y3Ga5O12 crystalline thin films (1992)
    Springer
    Applied physics 54 (1992), S. 470-473 
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    ISSN: 1432-0630
    Keywords: 71.70 ; 42.55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract The emission spectrum of Cr3+ in Y3Ga5O12 crystalline thin films at 10K is composed of the sharp R 1-line, its phonon sideband, and the very weak broadband. The lineshape of R 1-line at the peak wavelength of 689.8 nm cannot be fitted to a single Gaussian. This suggests that there exist several different Cr3+ sites in the thin film. This fact is confirmed by lifetime measurements; the radiative decay of the fluorescence is decomposed into multiple-exponential curves. The dominant component (2.8 ms) of the decay curve for the broadband emission is equal to those (2.4 ms) for R 1-line and its phonon sidebands. This result is discussed in terms of a tunneling model.
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    URL: http://dx.doi.org/10.1007/BF00324174
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    Temperature dependence of the non-Newtonian viscosity of elongated micellar solutions (1992)
    Springer
    Colloid & polymer science 270 (1992), S. 1035-1041 
    Details
    ISSN: 1435-1536
    Keywords: Elongated micelles ; cetyltrimethylammonium bromide (CTAB) ; non-Newtonianviscosity ; shearrate ; concentration ; temperature
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract We report in this work new results of the study on the non-Newtonian viscosity of aqueous micellar solutions of cetyltrimethylammonium bromide (CTAB) in the presence of potassium bromide (KBr), in the concentration range where the elongated micelles overlap. The experiments have been performed as a function of the surfactant concentration, temperature and shear rate by use of a Couette-viscosimeter. In the non-Newtonian range, at relatively low surfactant concentration (≲0.25 M/l), our results show that the flow curves obtained at different temperatures converge to a single liner curve with a characteristic slope varying with the surfactant concentration. These same data can be superposed on a master curve when appropriate reduced variables are used. The shape of the flow curves obtained at different temperatures for a sufficiently high surfactant concentration is similar to that obtained for monodisperse polymer solutions at different molecular weights. The slope obtained of about −1 is also predicted by Graessley's model in the theory of microviscoelasticity based on the concept of entanglement for polymer solutions. However, at surfactant concentration higher than 0.25 M/l our results show an unusual behavior. Above some critical shear rate it is possible to obtain an increase of the apparent viscosity with temperature. One possible explanation of this effect can be found in the increase of the entanglement with concentration coupled with the temperature and direct now effects on scission and recombination rate of the micelles.
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    URL: http://dx.doi.org/10.1007/BF00655973
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    Femtosecond-excimer-laser patterning of YBa2Cu3O7 films (1991)
    Springer
    Applied physics 53 (1991), S. 282-283 
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    ISSN: 1432-0630
    Keywords: 61.80 ; 42.55 ; 74.70
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract Projection patterning of Y-Ba-Cu-O films on (100) SrTiO3 and (100) MgO substrates using femtosecond KrF-excimer-laser pulses is reported
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    URL: http://dx.doi.org/10.1007/BF00324265
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    Simulation of water allocation and salt movement in the root zone (1991)
    Springer
    Water resources management 5 (1991), S. 121-147 
    Details
    ISSN: 1573-1650
    Keywords: Irrigation ; agriculture ; soil moisture ; salinity ; crop yield models ; mathematical modelling ; water use in agriculture ; simulation model
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying , Geography
    Notes: Abstract This paper is concerned with the simulation of the water allocation and salt movement in the root zone of a particular crop. A mathematical model of four ordinary differential equations is developed. The model performs water balance and salt balance in unsaturated and saturated regions of the root zone. It is a lumped input and lumped parameter conceptual model, which considers the average soil moisture and salt concentration in the root zone. The equations are solved numerically over the time period of the growing season. Precipitation and irrigation water are treated as inputs. The analyzed results indicate that, for the shallow water table case, the water table elevation has an important effect on the soil moisture depletion dynamics of the unsaturated zone. An appreciable amount of water from the saturated zone is transferred through capillary rise to the unsaturated zone particularly in the case of sandy loam soils. It was found that the water table elevation varies significantly during the growing season. The salt movement simulation indicates a salt concentration build up in the unsaturated zone during the growing season. Contours of equal crop yield reduction as a function of the unsaturated zone initial salt concentration and the irrigation water salt concentration are obtained. The model was tested with data from the Mashtul Pilot Area in Egypt and its performance was satisfactory.
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    Disorder and the shape of the R-lines in Cr3+-doped garnets (1990)
    Springer
    Applied physics 50 (1990), S. 565-572 
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    ISSN: 1432-0630
    Keywords: 78.40 ; 78.55 ; 42.55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract This paper describes measurements of the R-line emission from Cr3+ ions in Y3Ga5O12, Gd3Sc2Ga3O12, and Gd3Sc2Al3O12. Discrete splittings of the lines are interpreted as due to disorder on the cation sublattices. Assuming statistical distributions of the cations on the different cation sublattices enables estimates to be made of the degree of non-stoichiometry in the crystals.
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    The modification of the triple helical structure of gelatin in aqueous solution I. The influence of anionic surfactants, pH-value, and temperature (1988)
    Springer
    Colloid & polymer science 266 (1988), S. 1061-1067 
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    ISSN: 1435-1536
    Keywords: Circular dichroism ; gelatin ; sodium alkyl sulphates ; aqueousgelatinsolutions ; secondary structure ; pH ; temperature
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The modification of the triple helical structure in aqueous gelatin solutions by changing pH and adding alkyl sulphates at 298 K and after rechilling the solution to 283 K was investigated by CD-measurement. At 298 K the triple helical content at the IEP of the gelatin has its maximum value. It is only weakly affected by adding sodium dodecyl sulphate (SDDS) at concentrations 〈10−4 M/dm3. The unfolding of the triple helix affected by pH and SDDS is reversible by rechilling the solution. The triple helical content of gelatin solutions decreases at SDDS concentrations higher than 10−4 M/dm3. In all cases the decrease of the amount of triple helical structure is connected with an increase of the cis-configuration in single chains and leads to chain reversals. At sufficiently high SDDS concentrationsβ-sheets are formed. These changes are thermally irreversible. Sodium decyl sulphate (SDS) has a more minor influence than SDDS except in the range of the c.m.c. of SDS. At sufficiently high SDS concentrations,β-turns appear.
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    Kinetic studies on void formation during liquid epoxy resin impregnation through polyester non-woven fabric (1985)
    Springer
    Colloid & polymer science 263 (1985), S. 454-461 
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    ISSN: 1435-1536
    Keywords: Impregnation ; void ; liquid ; fabric ; temperature
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Under the condition that liquid epoxy resin impregnation was through polyester non-woven fabric sheets, sandwiched between two circular glass plates, the increase in gas pressure caused by decrease in the volume of non-impregnating area was not as much as expected according to Boyle's law. Hence, the quantity of the gas consumed by dissolution and diffusion into the liquid resin and the polyester fibers, as well as by the void formation in the impregnating area of liquid resin, was calculated. According to the results, the quantities of gas decreased by dissolution and diffusion from the non-impregnating area into the impregnating liquid resin and into the polyester fiber are found to be so small that the deviation from Boyle's law mostly depends on the gas consumption due to the void formation in the impregnating area. Observing the impregnating region with a microscope, many voids were found in the area between the non-impregnating area and the completely impregnated area. The number and size of voids are theoretically estimated by assuming the non-uniformity of the fiber distribution in the polyester non-woven fabric.
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    Spectral studies of Nd3+ and Er3+ ions in POCl3:SnCl4 laser liquid (1985)
    Springer
    Applied physics 38 (1985), S. 285-291 
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    ISSN: 1432-0630
    Keywords: 42.55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract The optical absorption spectra of triply ionized neodymium and erbium ions in POCl3∶SnCl4 laser liquid have been studied for the first time in the UV-VIS and NIR regions. Spectroscopic and Judd-Ofelt intensity parameters are evaluated from the observed band positions and their intensities. Radiative lifetimes and the luminescent branching ratios for the excited fluorescent levels of Nd3+ and Er3+ ions are theoretically estimated and the possible laser transitions are indicated. From the observed splittings of certain bands in the second-derivative spectrum of the Nd3+ ion, the crystal field (A 20,A 40) parameters are evaluated assumingC 3h symmetry for the ion.
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    StimulatedC'-emission of Ag−-centers in KI, RbBr, and CsBr (1985)
    Springer
    Applied physics 38 (1985), S. 61-65 
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    ISSN: 1432-0630
    Keywords: 42.55 ; 78.55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract Stimulated emission around 335 nm in theC' emission band of Ag− centers in KI, RbBr, and CsBr has been observed at low temperatures and the gain coefficient in the band maximum has been determined. Laser action has been demonstrated using a simple broad band cavity.
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    Temperature dependence of liquid epoxy resin impregnation through polyester non-woven fabric (1983)
    Springer
    Colloid & polymer science 261 (1983), S. 834-845 
    Details
    ISSN: 1435-1536
    Keywords: Impregnation ; capillary ; liquid ; fabric ; temperature
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The temperature dependence of liquid epoxy resin impregnation under atmospheric pressure was measured under the condition that the impregnation was through polyester non-woven fabric sheets, sandwiched between two circular glass plates. It was expected that impregnation would take place to a small extent, because the pressure in the sheet increases to more than atmospheric pressure in the course of impregnation from the perimeter of the circular sheet toward its center, but the liquid resin impregnates to a great extent and impregnating velocity increases with a rise in temperature. This phenomenon can be analyzed by the Kozeny-Carman equation improved by the introduction of the theoretically calculated capillary force in the modeled fiber bed structure and a parameter to postulate gas solubility and diffusion into the liquid resin. An increase in the impregnating velocity with the temperature rise is caused by decrease in the resin viscosity, by increase of the capillary force pressure and by decrease in the gas pressure corrected by a parameter.
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    Simultaneous operation at two different wavelengths of an PrLaP5O14 laser (1981)
    Springer
    Applied physics 24 (1981), S. 13-20 
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    ISSN: 1432-0630
    Keywords: 42.55 ; 78.60
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract Simultaneous laser operation at the wavelengths of λ1=637 and λ2=717 in Pr0.5La0.5P5O14 single crystals was observed. The crystals were excited by nanosecond publses from a Coumarin 2 dye laser (λ=450 nm). Laser emissions and their interdependence were studied both in crystals without an external resonator and in crystals placed within a plane parallel resonator. The energetic, time and frequency characteristics for both laser actions were examined. The effect of bifrequential emission was also found in crystals of different ratios of Pr and La ions concentration and in pure praseodymium pentaphosphate.
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    Infrared laser emission in two-photon pumped sodium vapour (1981)
    Springer
    Applied physics 24 (1981), S. 33-38 
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    ISSN: 1432-0630
    Keywords: 42.55 ; 33.80
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract We report infrared laser emission in the region of 3 to 5 μm from sodium vapour optically pumped by a pulsed dye laser with wavelengths ranging from 585 to 610nm. Twophoton excitation processes are believed to be responsible for the primary excitation. Both molecular transitions (4 to 5 μm) between high lying states, and atomic transitions (52 S 1/2−42 P 3/2,1/2 at 3.41 μm) have been identified.
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    On the homogeneization of transverse gas discharges by preionization (1981)
    Springer
    Applied physics 24 (1981), S. 267-272 
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    ISSN: 1432-0630
    Keywords: 52 ; 42.55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract Detailed data of the minimum preionization electron density (MPED)n 0 necessary to initiate a homogeneous discharge mode in transverse gas discharges are computed. An upper limit for the inductance of the discharge circuit is set by the power balance during breakdown. The results are presented as functions of generalized parameters. Applicability of the computations is proved by experimental observations.
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    Theoretical and experimental investigations of a passively mode-locked Nd: Glass laser (1981)
    Springer
    Applied physics 24 (1981), S. 341-348 
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    Keywords: 42.55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract The presented theoretical model for a mode-locked Nd-glass laser simultaneously takes into account dynamics of the mode-locking dye, amplification saturation and radiation background. A systematic variation of laser parameters gives insight into the pulse formation process and allows to improve the laser design. The calculations show that it should be possible to decrease considerably the duration of light pulses of a mode-locked Nd-glass laser. Using a new mode-locking dye with a switching time of τ=2.7×10−12 s we obtained stable laser operation and a pulse duration of 1.7×10−12s.
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    Measurement of atomic parameters for the3 D 1 state of I–II (1981)
    Springer
    Applied physics 25 (1981), S. 31-34 
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    ISSN: 1432-0630
    Keywords: 35 ; 42.55 ; 42.65
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract The decay rates of the3 D 1 level of I–II and the 3s 2 level of neon have been measured by the magnetic-field power dip method. The decay rate at the zero-pressure limit is found to be 7.1 MHz/2π for the3 D 1 level. The collision cross-section for excited I ions with helium atoms equals 0.19×10−15 cm2.
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    Solvent dependent characteristics of XeCl pumped UV dye lasers (1981)
    Springer
    Applied physics 25 (1981), S. 17-22 
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    ISSN: 1432-0630
    Keywords: 42.55 ; 82.50
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract The characteristics of near uv dye lasers pumped with short duration, 308 nm pulses from a XeCl laser are described with particular emphasis on the parameters influencing high average power operation. The solvent is shown to effect the operation of all dye lasers studied, particularly the photochemical stability. Measurements of the efficiency, as a function of the integrated pump energy have been made for a series of dye-solvent combinations. With the best combinations, average output powers in excess of 1W and conversion efficiencies greater than 25% were obtained at a repetition rate of ∼100 Hz.
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    A hollow cathode carbon atom laser (1981)
    Springer
    Applied physics 25 (1981), S. 273-274 
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    ISSN: 1432-0630
    Keywords: 42.55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract Near-infrared laser action of atomic carbon was obtained using a hollow cathode discharge tube. Besides the known 1.4543 μm and 1.0691 μm laser lines, cw laser operation at 1.0683 μm, 0.9658 μm, and 0.9406 μm wavelength was observed for the first time. The source of carbon was due to dissociation of CO, CO2 or CH4 added to the He buffer gas.
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    A linac-pumped excimer laser: Fluorescence and scaling studies (1981)
    Springer
    Applied physics 25 (1981), S. 329-336 
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    ISSN: 1432-0630
    Keywords: 42.55 ; 78.55
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    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract This work was an experimental investigation of a potential large-scale excimer laser system, in which a high-pressure KrF gas mix was pumped by the 4-MeV electron beam from an available linear accelerator. As a function of the mix and the pressure, fluorescence from KrF* and/or Kr2F* were produced with good efficiency. Comparing measured data with a kinetic model, it was found that the kinetics followed the “normal” patterns seen in low-energy electron pumping. The data fitting process also resulted in a new value for the three-body quenching rate constant for reactions involving Ar. A critical factor in the development of this laser will be an improvement in beam control over that afforded by a simple solenoidal magnet. The conditions necessary for lasing are predicted; no inherent limitations on scaling of the device were found.
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    Bistability of a CO2 laser with SF6 intracavity as an absorber: Transient effects (1981)
    Springer
    Applied physics 24 (1981), S. 45-48 
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    ISSN: 1432-0630
    Keywords: 42.55 ; 42.65 ; 64
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract We investigated time-dependent effects related to the bistable operation of a CO2 laser with an intracavity nonlinear absorber (SF6). The response of the system to small perturbations was sensitively dependent on the operating laser line [P(12)→P(30)] of the 10.6 μm band. The narrow bistable region forP(12), due to a very narrow hysteresis loop, can be effectively utilized for optical switching, because of its pronounced sensitivity to variations in operational parameters. The maximum admissable beam blocking time (intracavity) for spontaneous return to lasing was measured forP(16), for a range of absorber pressures. This τm is related to the relaxation time of the upper level in the absorber.
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    Radiocarbon dating by infrared laser spectroscopy (1981)
    Springer
    Applied physics 24 (1981), S. 381-386 
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    ISSN: 1432-0630
    Keywords: 33 ; 42.55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract A tunable diode laser and a multipass optical cell are used to investigate the feasibility of performing radiocarbon dating by means of infrared spectroscopy. We show that the detection of14CO2 at concentrations of14C/12C≲10−12 is not limited by interferences from the background of normal CO2 molecules, provided the gas sample is cooled. Using short-time constants, the present sensitivity of the infrared technique is comparable to that of an ideal disintegration counter. The experimental results are extrapolated to long time constants to demonstrate that radiocarbon dating by infrared spectroscopy is feasible, and that carbon samples with a mass of less than 1 gm can be dated by this technique.
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    Two-wavelength dye-laser operation using a reflecting Fizeau interferometer (1981)
    Springer
    Applied physics 24 (1981), S. 7-9 
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    ISSN: 1432-0630
    Keywords: 42.55
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    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract Newly found reflection properties of the Fizeau wedge interferometer are shown to be of particular advantage in obtaining efficient multi-wavelength operation of dye lasers. Use is made of the fact that the reflecting Fizeau wedge can ensure at once a selective feedback for a given wavelength and quasi-total reflection in an other direction for all other wavelengths. Fully independent tuning of two 0.02 nm lines is obtained with short pulse (2 ns) N2-laser pumping using a single Fizeau wedge.
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    Pulse properties of a synchronously mode-locked, cavity dumped, picosecond dye laser system (1981)
    Springer
    Applied physics 24 (1981), S. 233-238 
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    ISSN: 1432-0630
    Keywords: 42.55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract A synchronously mode-locked, cavity-dumped picosecond dye laser is described. The structure and intensity of the picosecond pulses measured under different conditions are reported. It was found that the structure of the pulses from the synchronously pumped dye laser depends critically on the length of the Ar+ laser pulses. At the shortest Ar+ laser pulses of about 70 ps the dye pulses are as short as 1.1 ps. With Ar+ laser pulses of 200 ps the dye laser pulses contains a broad satellite pulse which contains a large fraction of the total intensity. When a cavity dumper is added to the system one gets dye laser pulses 15–20 ps long with a substructure, which indicates incomplete mode-locking. Well mode-locked 1.5–2.0 ps pulses were obtained in the red part of the dye laser action spectrum, i.e. 620–650 nm for R6G, 595–608 nm for R 110 and 657–662 nm for RB, respectively. Addition of mode-locking dyes also improved the pulse quality at some wavelengths.
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    Optimization of dye-laser output coupling by consideration of the spatial gain distribution (1980)
    Springer
    Applied physics 22 (1980), S. 175-184 
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    ISSN: 1432-0630
    Keywords: 42.55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract The problem of output-coupling optimization of a transversely or longitudinally pumped dye laser is treated in terms of a rate equation approach under steady state considerations. The theoretical study considers the spatial variation of the gain distribution and such typical features of a dye laser as reabsorption, triplet effects and excited state absorption. Numerical results obtained with realistic values of typical laser parameters (cross-sections for stimulated emission and reabsorption, number density of active molecules etc.) indicate that a higher degree of output coupling and consequently higher output powers are feasible upon a complete consideration of the spatial gain distribution
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  • 79
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    New TEA-lasers based onD′→A′ transitions in halogen monofluoride compounds: ClF (284.4 nm), BrF (354.5 nm), IF (490.8 nm) (1980)
    Springer
    Applied physics 23 (1980), S. 283-287 
    Details
    ISSN: 1432-0630
    Keywords: 42.55 ; 42.80 ; 33
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract As an outcome of a systematic study of excitation kinetics and fluorescence spectra concerning theD′(3π2u )→A′(3π2g ) transitions in homonuclear diatomic halogens and corresponding transitions in interhalogen molecules [1], this paper describes, for the first time, TEA laser action in the three halogen monofluorides ClF, BrF, and IF. Output energies in the mJ range were demonstrated in a fast TEA discharge arrangement at the wavelengths of 284.4, 354.5, and 490.8 nm for ClF, BrF, and IF, respectively. The results suggest parameter scalability and wavelength tunability.
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    URL: http://dx.doi.org/10.1007/BF00914912
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  • 80
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    The effect of substituting metal vapour with metal halide vapour in a hollow cathode laser discharge (1980)
    Springer
    Applied physics 21 (1980), S. 25-28 
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    ISSN: 1432-0630
    Keywords: 35 ; 42.55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract He−Zn and He−ZnCl2 hollow cathode discharges were compared. The metal vapour concentration necessary for laser operation can be achieved at a lower temperature for the molecular substance. On the other hand, the efficiency decreases because part of the He ions necessary for the selective excitation of the upper laser level of the metal ion are lost in the dissociation process.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00886479
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  • 81
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    Application of pressure-tuned diode lasers to high-resolution spectroscopy (1980)
    Springer
    Applied physics 22 (1980), S. 241-243 
    Details
    ISSN: 1432-0630
    Keywords: 07.65 ; 42.55 ; 42.80
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract The application of the high-pressure chamber with a pressure transmitting medium (liquid at room temperature) to diode-laser tuning was found to be a useful method for high-resolution spectroscopy. Ammonia absorbtion spectra in the 10 μm region were recorded with a resolution approaching the Doppler limit.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00886014
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  • 82
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    Wide-range line-tunable oscillation of an optically pumped NH3 laser (1980)
    Springer
    Applied physics 21 (1980), S. 237-240 
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    ISSN: 1432-0630
    Keywords: 42.55 ; 42.60 ; 34.50
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract Selective single-line oscillation has been obtained from an NH3 laser in the range from 11 to 13 μm. Pumping of high pressure NH3−He mixture with theR(30) line of a TEA-CO2 laser made it possible to tune on more than 30 lines with the aid of a grating. However, such line tunable oscillation was not observed when theR(16) line was used for pumping. Reasons for this difference are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00886173
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  • 83
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    Simplification of the helical TE N2 laser (1980)
    Springer
    Applied physics 21 (1980), S. 319-321 
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    ISSN: 1432-0630
    Keywords: 42.55 ; 42.60
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract We report the observation that the helical TE N2 laser can effectively be simplified by giving up the use of decoupling elements as well as by abolishing the segmentation of the electrode structure. Although, as a consequence of this simplification, the operating pressure range was slightly decreased, the output power could be improved by roughly 30%, a result which is attributed to the new electrode geometry exhibiting lower inductance and lower damping losses.
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    URL: http://dx.doi.org/10.1007/BF00895921
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  • 84
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    Selective action on nucleic acids components by picosecond light pulses (1980)
    Springer
    Applied physics 21 (1980), S. 391-395 
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    ISSN: 1432-0630
    Keywords: 87 ; 42.55 ; 82.50
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract We report on first attempts for selective action on nucleic acid components, namely uracil and adenine, using picosecond light pulses. Selective action was achieved both in the case of irradiation of mixtures of bases and in the case of irradiation of mixtures of different nucleic acids components, which contain uracil and adenine.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00895931
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  • 85
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    Periodic pulse solutions of a laser consisting of a pair of amplifiers mode locked by a fast saturable absorber (1980)
    Springer
    Applied physics 22 (1980), S. 213-218 
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    ISSN: 1432-0630
    Keywords: 42.55 ; 42.60 ; 42.65
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract We present periodic solutions, which are described in terms of Jacobian elliptic functions, for the steady state pulses from a laser system consisting of a pair of amplifiers of unequal relaxation time mode locked by a “fast” saturable absorber. The pulsewidth and the average power in the pulse are expressed interms of the system parameters through two different approaches, where detailed plots are given for one of the approaches. Summary of the characters to be possessed by the amplifier pair to ensure the reliable production of shortest possible pulses is given.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00886009
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  • 86
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    Modelling of a solar-pumped MHD excimer laser (1980)
    Springer
    Applied physics 22 (1980), S. 277-281 
    Details
    ISSN: 1432-0630
    Keywords: 42.55 ; 52
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract An analytical model is applied to the concept of a solar-pumped MHD laser utilizing the CsXe excimer and Cs2 dimerA-X laser transitions. The model predicts practical gain coefficients on the excimer band for supersonic flow of a 2000 K, 20 atmosphere cesium-xenon plasma across a ∼10 kG magnetic field.
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    URL: http://dx.doi.org/10.1007/BF00899877
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  • 87
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    Gasdynamic CO laser with closed-cycle gas flow (1980)
    Springer
    Applied physics 22 (1980), S. 421-427 
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    ISSN: 1432-0630
    Keywords: 42.55 ; 47 ; 52
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract The operation of an electrically excited gasdynamic CO laser with closed-cycle gas flow is described. Details of the gasdynamics, the recompression, and the cooling of the flowing gas are given. The electrical discharge produces contaminating gas compounds—in particular CO2—which accumulate in the recirculating gas. The resulting transient behavior of the laser gas composition, the discharge characteristics, and the laser performance are studied and compared with the results obtained with the same CO laser in an open-flow system. It is found that the closed-cycle system may be operated for considerable time if the CO2 contamination is removed from the laser gas.
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    URL: http://dx.doi.org/10.1007/BF00901068
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  • 88
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    Solubility limit of impurities in silicon after laser induced melting (1980)
    Springer
    Applied physics 23 (1980), S. 15-19 
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    ISSN: 1432-0630
    Keywords: 64.75+g ; 61.70T ; 42.55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract The solubility of several dopants (Sb, Ga, Bi, In) in laser treated silicon has been investigated. The dopants were introduced by vacuum deposition followed by ruby laser irradiation. Their solubility was determined by Rutherford backscattering spectroscopy measurements in channelling and random conditions. In all cases, a maximum solubilityC S * , much higher than the equilibrium solubility limitC S 0 and independent of the pulsed laser energy density, was found. The values obtained are in good agreement with those calculated from a simple model based on phase diagram considerations, using the relationship: $$C_S^* = \frac{{C_S^0 }}{{k_0 }}k^* ,$$ wherek 0 andk * are the equilibrium and effective distribution coefficients. Finally, the existence of a new solubility limit for a laser treatment is discussed.
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    URL: http://dx.doi.org/10.1007/BF00899564
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  • 89
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    New cw FIR laser lines from optically pumped ammonia analogues (1980)
    Springer
    Applied physics 23 (1980), S. 127-130 
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    ISSN: 1432-0630
    Keywords: 42.55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract Two new cw submillimetre lines optically pumped by the 9 μR(30) CO2 laser have been observed for14NH3 and assigned to thea(6,0)→s(5,0) transition and to its cascade transitions(5,0)→a(4,0) in thev 2=1 state. In addition, six new emission lines have been observed for NH2D, and one tentatively assigned to the (11,1)→(10,1) transition of ND3. Methylamine has also been investigated and twenty-eight new emission lines have been discovered.
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    URL: http://dx.doi.org/10.1007/BF00899706
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  • 90
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    A high power N2-laser of long pulse duration (1980)
    Springer
    Applied physics 23 (1980), S. 341-344 
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    ISSN: 1432-0630
    Keywords: 42.55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract An N2-laser of 19 ns pulse-duration and an energy of 30 mJ has been developed and examined. A dc preionization, a grooved electrode and a partial electrical screening of the discharge tube permit reproducible single-shot operation and yield a homogeneous beam.
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    URL: http://dx.doi.org/10.1007/BF00903212
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  • 91
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    Detection of CO2-laser power variations via plasma tube impedance changes (1980)
    Springer
    Applied physics 21 (1980), S. 407-409 
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    ISSN: 1432-0630
    Keywords: 42.55 ; 52 ; 85.60
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract A method is described for detection of CO2-laser power variations which requires no optical detector. It is based on plasma-tube impedance changes induced by the laser power flow within the cavity. A constant-current high-voltage power supply and a special equalizer are necessary to obtain a voltage proportional to the laser power. Details for the design of the equalizer are given. The detection scheme works for frequencies up to about 5 kHz and can be used for laser frequency stabilization or signature analysis.
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    URL: http://dx.doi.org/10.1007/BF00895933
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  • 92
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    Stability of Pin electrode CO2-lasers (1980)
    Springer
    Applied physics 22 (1980), S. 149-154 
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    ISSN: 1432-0630
    Keywords: 42.55 ; 52
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract The stability of parallel pin electrode CO2-laser discharges, coupled by carrier diffusion only, against concentration of current in one column and subsequent transition into an arc, is investigated theoretically. A small signal description of the time dependent behaviour of a column with falling characteristic caused by a wall sheath of considerable width is used. It is shown that an inductance in series to each discharge is not able to avoid glow to arc transition, though enlarges the duration of the glow.
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    URL: http://dx.doi.org/10.1007/BF00885998
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  • 93
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    Spectral, fluorescent, photochemical and laser properties of some organic compound vapors (1980)
    Springer
    Applied physics 23 (1980), S. 83-87 
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    ISSN: 1432-0630
    Keywords: 33 ; 82.50 ; 42.55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract Absorption and fluorescence spectra of rarefied vapors ofp-terphenyl, 1,4-bis-[2(5-phenyloxazolyl)]-benzene, 2,5-diphenyl-1,3,4-oxadiazole, 2,5-diphenyl-1,3-oxazole, 2,5-diphenylfuran are measured. Extinction coefficients, quantum yields of fluorescence and one-photon decomposition of molecules are determined for vapors excited by pulsed laser radiation at 266 and 355 nm in the temperature range from 200 to 400°C. It is shown that for all cases studied the one-photon decomposition is only a small part of the total quantum yield of the radiationless deactivation of the fluorescent state. Laser action has, for the first time, been obtained in 2,5-diphenylfuran vapor at 356 nm.
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    URL: http://dx.doi.org/10.1007/BF00899574
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  • 94
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    Effect of laser dye deterioration on performance (1980)
    Springer
    Applied physics 22 (1980), S. 171-174 
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    ISSN: 1432-0630
    Keywords: 42.55 ; 82.50
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract A previous analysis that described loss of gain in a dye solution as a result of photochemical decomposition by pump photons is refined and is extended to the situation where impurities absorb at the pump wavelength. A limitation in the first paper is that it described only a single absorption depth in the medium at a constant pump fluxI p. The present examination includes the fall-off ofI p and integrates the total signal output with depth for a single-pass amplifier operated in the fully saturated gain condition. The equations are simpler, but as before loss of output, expressed in terms of a quantum yield of laser decayQ L, is minimized for a photochemically bleachable dye, and for one with high gain. Pumping in the vicinity of the absorption maximum is also advantageous.
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    URL: http://dx.doi.org/10.1007/BF00886001
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  • 95
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    Infrared fluorescence and laser action of fast mode-locking dyes (1980)
    Springer
    Applied physics 22 (1980), S. 355-359 
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    ISSN: 1432-0630
    Keywords: 32 ; 42.55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract Fluorescence spectra in the near infrared are observed of the dye Eastman 9860 and of new, faster mode-locking dyes. The quantum efficiencies are determined to be small with η≃10−3. The short fluorescence lifetimes are deduced from optical gain measurements. The fluorescence time-constants are found to have the same value as the corresponding absorption recovery times. Even laser action is observed in these fast saturable absorbers previously belieyed to be non-fluorescent.
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    URL: http://dx.doi.org/10.1007/BF00901056
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  • 96
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    A novel picosecond-pulse dye laser system (1980)
    Springer
    Applied physics 23 (1980), S. 135-140 
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    ISSN: 1432-0630
    Keywords: 42.55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract A laser system capable of generating picosecond pulses of 2 ps duration and peak powers of up to 50 MW, tunable throughout the emission spectrum of the lasing medium is described. The system consists of a cw dye laser which is tuned and is actively mode-locked by means of a novel interferometer. Single-pulse amplification is achieved via a two-stage N2-laser-pumped amplifier arrangement. One of the most attractive features of the system here described is its inherent versatile broad tunability, which should allow, with different lasing media and pump sources, ps pulse generation from 400 to 700 nm using the same interferometer device.
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    URL: http://dx.doi.org/10.1007/BF00899708
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  • 97
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    An analysis of stimulated longitudinal electrostatic bremsstrahlung in a free-electron laser structure (1980)
    Springer
    Applied physics 23 (1980), S. 295-298 
    Details
    ISSN: 1432-0630
    Keywords: 41 ; 42.55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract An analysis of stimulated emission of radiation by an electron beam passing through a periodic longitudinal electrostatic field is presented, and its use in a free-electron laser structure is discussed. The analysis is based on a coupled-mode calculation of the interaction between a waveguided electromagnetic mode and an electron-beam plasma with finite cross section. The dispersion equation derived applies to the collective as well as the single electron regime.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00914914
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  • 98
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    Excimers and excimer lasers (1980)
    Springer
    Applied physics 21 (1980), S. 95-114 
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    ISSN: 1432-0630
    Keywords: 42.55 ; 42.60
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract The development of excimers and excimer lasers are reviewed. The excimers of the noble gases (Xe 2 * , Kr 2 * , Ar 2 * ) and of the noble gas halides (e.g. KrF, XeCl) which, respectively, radiate in the vacuum ultra-violet and ultra-violet regions of the spectrum are described in terms of their structure, spectroscopy and formation kinetics and the methods of pumping, operational characteristics and applications of the lasers are discussed.
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    URL: http://dx.doi.org/10.1007/BF00900671
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  • 99
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    Experimental method for the measurement of hyperfine transition saturation intensities in a gaseous medium (1980)
    Springer
    Applied physics 21 (1980), S. 135-140 
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    ISSN: 1432-0630
    Keywords: 35 ; 42.55 ; 42.80
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract A saturated absorption technique, using an actively stabilized cw dye laser has been developed to measure the saturation intensities of hyperfine transitions in a gaseous medium. Hyperfine lines belonging to theB-X system of molecular iodine have been investigated. The experimental method proposed, provides a means for measurement of the absolute value of the saturation parameter of the transition with an accuracy better than 10%. The behavior of the saturation intensity of some transitions with iodine pressure has been investigated in the range 30 m Torr→90mTorr.
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    URL: http://dx.doi.org/10.1007/BF00900675
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  • 100
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    Energy transfer in constant period free-electron lasers (1980)
    Springer
    Applied physics 22 (1980), S. 219-225 
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    ISSN: 1432-0630
    Keywords: 42.55
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract A simple single particle model of a free-electron laser (FEL) amplifier has been used in a computer simulation to determine the maximum fractional conversion of electron kinetic energy to laser energy. The simulation results can be represented by a single universal curve. A simple scaling relationship for the length of the optimized constant period helix together with the universal curve permit one to predict maximum fractional energy conversion for any set of values of initial electron energy, initial laser intensity, magnetic field amplitude, and magnet period.
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    URL: http://dx.doi.org/10.1007/BF00886010
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