ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • ESR
  • Inversion
  • Elsevier  (676)
  • Springer  (153)
  • European Association of Exploration Geophysicists  (5)
  • Wiley  (2)
  • 3  (1)
  • 1
    facet.materialart.
    Unknown
    Tortonian-Pleistocenic oceanic features in the Southern Tyrrhenian Sea: magnetic inverse model of the Selli-Vavilov region (2009)
    Springer
    Details
    Publication Date: 2017-04-04
    Description: We show the magnetic model of the Selli-Vavilov region. The Selli Line is known as the northwestern edge of the southern Tyrrhenian basin. The tectonic evolution of the Tyrrhenian basin is dominated by a Tortonian - Quaternary extension through the eastward movement of the Apennine subduction system. This migration has generated a diffuse stretching of the continental crust with the emplacement of new oceanic material. This latter occurred in several localized zones where the eastward retreating of the Ionian subduction system produced a strong depletion of the crust with formation of basins and correlated spreading. Nowadays the presence of oceanic crust is confirmed through direct drilling investigation but a complete mapping of the oceanic crustal distribution is still lacking. The Selli-Vavilov region shows a differentiated crustal setting where seamount structures, the oceanic basement portions and continental crust blocks are superimposed. To this aim, a 2D inversion of the magnetic data of this region was conducted to define buried structures. The magnetic susceptibility pattern was computed by solving the least squares problem of the misfit between the predicted and real data for separated wavebands. This method produced two 2D models of the high and low frequency fields of the Selli-Vavilov region. The two apparent susceptibility maps provide different information for distinct ranges of depth. The results of the inversions were also combined with seismic data of the Selli region highlighting the position of the highly-magnetized buried bodies. The results confirm a role for the Selli Line as a deep crustal boundary dividing the Sardinian passive domain from the easternmost active region where different oceanic structures are located. The Selli Line has worked as a detachment fault system which has moved eastward. Finally, the Selli-Vavilov region may be interpreted as a tectonic result due to a passive asymmetrical rift occurred between the Tortonian and Pliocene.
    Description: Published
    Description: 251-266
    Description: 2.6. TTC - Laboratorio di gravimetria, magnetismo ed elettromagnetismo in aree attive
    Description: 3.4. Geomagnetismo
    Description: 3.5. Geologia e storia dei sistemi vulcanici
    Description: JCR Journal
    Description: reserved
    Keywords: Geomagnetism ; Tectonics ; Geodynamics ; Inversion ; Oceanic crust ; Volcanic structure ; 04. Solid Earth::04.05. Geomagnetism::04.05.04. Magnetic anomalies ; 04. Solid Earth::04.07. Tectonophysics::04.07.02. Geodynamics ; 05. General::05.01. Computational geophysics::05.01.03. Inverse methods
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 2
    facet.materialart.
    Unknown
    Potential-field inversion for a layer with uneven thickness: The Tyrrhenian Sea density model (2008)
    Elsevier
    Details
    Publication Date: 2017-04-04
    Description: Inversion of large-scale potential-field anomalies, aimed at determining density or magnetization, is usually made in the Fourier domain. The commonly adopted geometry is based on a layer of constant thickness, characterized by a bottom surface at a fixed distance from the top surface. We propose a new method to overcome this limiting geometry, by inverting in the usual iterating scheme using top and bottom surfaces of differing, but known shapes. Randomly generated synthetic models will be analyzed, and finally performance of this method will be tested on real gravity data describing the isostatic residual anomaly of the Southern Tyrrhenian Sea in Italy. The final result is a density model that shows the distribution of the oceanic crust in this region, which is delimited by known structural elements and appears strongly correlated with the oceanized abyssal basins of Vavilov and Marsili.
    Description: Published
    Description: 105-111
    Description: 2.6. TTC - Laboratorio di gravimetria, magnetismo ed elettromagnetismo in aree attive
    Description: JCR Journal
    Description: reserved
    Keywords: Potential field ; Inversion ; Mathematical modeling ; Tyrrhenian Sea ; 04. Solid Earth::04.02. Exploration geophysics::04.02.99. General or miscellaneous ; 04. Solid Earth::04.02. Exploration geophysics::04.02.02. Gravity methods
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 3
    facet.materialart.
    Unknown
    Automatic versus manual model differentiation to compute sensitivities and solve non-linear inverse problems (2002)
    3
    In:  Computers and Geosciences, Münster, 3, vol. 28, no. 45, pp. 309-326, pp. L11609, (ISBN 0-471-26610-8)
    Details
    Publication Date: 2002
    Keywords: Inversion ; Data analysis / ~ processing ; Non-linear effects ; Discrimination ; C&G
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    BIBLIOGRAPHY SEISMOLOGY
  • 4
    facet.materialart.
    Unknown
    Geophysical Inverse Theory and Regularization Problems (2002)
    Elsevier
    In:  Amsterdam, 628 pp., Elsevier, vol. 31, no. 1, pp. 1-40, (ISBN 0-691-01019-6)
    Details
    Publication Date: 2002
    Keywords: Textbook of geophysics ; Inversion ; instability ; well-posed ; ill-posed ; problems ; Least-squares ; Backus ; Gilbert ; Non-linear effects ; regularization ; potential ; Electromagnetic methods/phenomena ; Seismology ; Gram ; Schmidt ; Singular value decomposition ; Lanczos ; Green's function ; Tikhonov ; potential ; methods ; Seismics (controlled source seismology) ; Gravimetry, Gravitation ; Geomagnetics ; Textbook of mathematics ; seismic Migration
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    BIBLIOGRAPHY SEISMOLOGY
  • 5
    Electronic Resource
    Electronic Resource
    Spin Labels as the Instrument for Analysis of Topochemistry of Polymer-Immobilized Ziegler Catalytic Systems (2000)
    Springer
    Journal of inorganic and organometallic polymers and materials 10 (2000), S. 1-22 
    Details
    ISSN: 1572-8870
    Keywords: topochemistry ; polymer-immobilized complexes ; catalysts ; functionalized polymers ; metal complexes ; ESR ; spin labels
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract A spin labeling technique was used to investigate the topochemical characteristics of polymer carriers and immobilized metal complexes. Functionalized polyethylenes (PE) such as PE–grafted-polyallylamine (1), PE–grafted-polydiallyl-amine (2), and PE–grafted-poly-4-vinylpyridine (3), obtained by grafting polymerization of the corresponding monomers, were used as polymer carriers. Metal-containing polymers were obtained by immobilization to 2 with either TiCl4 (2/Ti) or Al(C2H5)2 Cl (2/Al). The stable nitroxyl radical 2,2,6,6-tetramethyl-4-(2′-oxy-4′,6′-dichlorotriazine)piperidine-1-oxyl $$(\dot R_1 )$$ was used for spin labeling 2 to give $$2/\dot R_1 $$ , while 2,2,5,5,tetramethyl-3-(N-acetoamidiiodine)-pyrrollidine-1-oxyl $$(\dot R_2 )$$ was used for spin labeling 3 to give $$3/\dot R_2 $$ . Radical 2,2,6,6-tetramethyl-4-hydroxy-pyperidine-1-oxyl $$(\dot R_3 )$$ was bonded to 2/Ti and 2/Al to give $$2/Ti/\dot R_3 $$ and $$2/Al/\dot R_3 $$ , respectively. The accessibility of the functionalized polymers 1–3 to interact with the spin labels and the immobilized metal complexes was examined. Estimation of the effective distances between the spin labels and the dynamic behavior of nitroxyl radicals in the functionalized polymer matrixes and metal-containing polymers revealed several important features of spin-labeled systems. Metallation of a functional covering makes the polymer more accessible for spin labeling and has a considerable effect on the dynamic characteristics of polymer matrix. A change of the rotational activation energy of the spin labels from 15 kcal/mol in $$2/\dot R_1 $$ to 44 kcal/mol for $$2/Ti(Al)/\dot R_3 $$ in the temperature range 100–150°C was observed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009494915016
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Kegelschnittbüschel und Inversion (2000)
    Springer
    Geometriae dedicata 83 (2000), S. 31-37 
    Details
    ISSN: 1572-9168
    Keywords: Vollständiges Viereck ; Kegelschnittbüschel ; Konjugiertheitsabbildung ; Inversion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract The conjugacy mapping rel. to a complete quadrangle in a Pappian projective plane of characteristic ≠2 is constructed by using a bijection of the line set onto the bundle of conics through the diagonal points of the quadrangle. The inversion with center O of the inversion circle going through the point P in the Euclidean plane proves to be the product of the reflection at OP and the affine restriction of the conjugacy mapping rel. to the quadrangle having P as one of its vertices and O together with the circular points at infinity as diagonal points.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1005294714649
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Formation of tetramethylethylene radical cations after pentane adsorption on sulfated zirconia (2000)
    Springer
    Catalysis letters 68 (2000), S. 209-214 
    Details
    ISSN: 1572-879X
    Keywords: sulfated zirconia ; pentane ; radical cations ; tetramethylethylene ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Tetramethylethylene radical cations have been registered by ESR after pentane adsorption on sulfated zirconia. The radical cations proved to be not stable in the presence of oxygen, only molecular oxygen radical anions being registered. Tetramethylethylene formation and pentane disproportionation are shown to occur under illumination within the same spectral region proving that the former is formed as a by-product of pentane transformations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1019039605154
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Redox and photo‐redox properties of isolated Mo5+ ions in MoH‐ZSM‐5 and MoH‐beta zeolites: in situ ESR study (2000)
    Springer
    Catalysis letters 64 (2000), S. 53-57 
    Details
    ISSN: 1572-879X
    Keywords: Mo‐ZSM‐5 ; Mo‐beta ; redox and photo‐redox properties ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Redox and photo‐redox properties of isolated Mo5+ ions stabilized in H‐ZSM‐5 and H‐beta zeolites are studied by in situ ESR in flowing O2, NO, H2, and C3H6. Upon oxidation of pre‐reduced samples at 20 °C, NO demonstrates a higher oxidative ability, as compared with O2. Interaction of Mo5+ ions with propene at 20 °C results in formation of a chemisorption complex with enhanced reactivity of Mo(V) toward NO. Illumination of the Mo5+/HZSM‐5 sample with UV‐visible light causes measurable acceleration of Mo(V) oxidation by NO at 20 °C. Therefore, photochemical activation of the oxidation step could be realized, in principle, for Mo/zeolite catalysts. At 500 °C in the reaction mixture NO + H2, the step of the catalytic site reduction is fast, and the dynamic equilibrium of the redox reaction Mo(VI) ↔ Mo(V) for MoH‐ZSM‐5 and MoH‐beta seems to be strongly shifted to Mo5+.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1019018532586
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    DC-resistivity mapping of internal landfill structures: two pre-excavation surveys (2000)
    Springer
    Environmental geology 39 (2000), S. 360-371 
    Details
    ISSN: 1432-0495
    Keywords: Key words Environmental geophysics ; Resistivity ; Inversion ; Landfill mining ; Waste ; Characterization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract  Geophysical investigations using 2-D DC resistivity were carried out on old parts of two similar landfills, with waste of different ages. The data sets, which included high data density in both vertical and horizontal directions, were interpreted with 2-D smoothness constrained inversion. The landfills were excavated after the surveying. The objective was to test the capability of the resistivity method as a pre-characterization technique. The objectives were only partially fulfilled. First, the moisture content was the parameter that appeared to exert the dominant control over the resistivity distribution of the landfill. The most important potential information that can be recovered is, therefore, an indication of the waste piles hydraulics. Second, it was neither possible to estimate the amount of recoverable soils, nor to correlate the type of waste with the resistivity models. However, discrete anomalies were identified, and if specific materials are searched for, the resistivity models indicate possible places to search.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002540050015
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Effect of calcination/rehydration treatments on the environment of V in β zeolite (2000)
    Springer
    Topics in catalysis 11-12 (2000), S. 379-390 
    Details
    ISSN: 1572-9028
    Keywords: β zeolite ; dealumination ; vanadium ; dehydroxylation ; FT-IR ; UV-visible ; ESR ; TPR ; 51V and 29Si NMR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract A dealuminated zeolite β has been contacted with solutions of ammonium metavanadate to incorporate vanadium as tetrahedral V species which are not removed under treatment with aqueous solution of ammonium acetate. The effects of calcination and rehydration on the environment of the V species have been studied by diffuse reflectance UV-visible and 51V NMR. The reducibility of the V species has been followed by TPR and ESR. The dehydroxylation/rehydroxylation process occurring in the β framework upon dehydration/rehydration has been monitored by 29Si MAS NMR and FT-IR spectroscopy.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1027219107921
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 11
    Electronic Resource
    Electronic Resource
    Thermoluminescent Properties of Tridymite SiO2 : Al3+, Eu3+ (2000)
    Springer
    Journal of sol gel science and technology 19 (2000), S. 737-740 
    Details
    ISSN: 1573-4846
    Keywords: SiO2 ; sol-gel ; thermoluminescence ; ESR ; Eu3+
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract SiO2 crystals have been used in electroluminescence devices and thermoluminescence (TL) dosimeters. However, their emission mechanisms have not yet been clearly explained. Recently, it has become possible to obtain amorphous, highly pure, SiO2 prepared by the sol-gel method. The emission mechanism of TL was investigated using Al3+ and/or Eu3+-doped SiO2 crystalline samples prepared by heat-treating under much lower temperature than the melting point of SiO2. The TL spectrum of Eu3+-doped sample had main peaks due to the electron transitions from 5D2 to 7F5 (ca. 570 nm, yellow peak) and from 5D0 to 7F2 (ca. 610 nm, red peak). The yellow peak intensity has a maximum value in the SiO2 doped with near 1 mmol% of Eu2O3, while the red peak intensity was almost constant. These facts suggest that bright yellow emission of SiO2TL phosphor is synthesized by the diffusion of Eu3+ ion in SiO2 matrix prepared by sol-gel method.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008791528896
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 12
    Electronic Resource
    Electronic Resource
    ESR Study of the Plasma Polymerizations of Trimethylsilane and Methane (2000)
    Springer
    Plasmas and polymers 5 (2000), S. 235-253 
    Details
    ISSN: 1572-8978
    Keywords: ESR ; plasma polymerization ; free radical ; thin films ; trimethylsilane ; methane ; PE
    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 Electron Spin Resonance (ESR) was used to study, at the molecular level, the plasma polymerization of trimethylsilane (TMS) and methane. Direct ESR analysis of the plasma coated Al substrate required the use of a novel ESR technique. TMS plasma deposit on Al showed a single broad resonance line near g = 2.003. The signal was stable in vacuum and decayed on exposure to air, with a significant fraction persisting for days. Results show that this signal arises from silicon dangling bonds. Identical TMS signals were observed from films prepared by the DC cathodic or the AF glow discharge method but their decay rates were different. In contrast, the deposition of methane produced two distinct types of carbon-based signals depending upon the method of deposition. TMS or CH4 films deposited by the DC cathodic method showed slow signals decay and high refractive indices value. While the use of Al as the substrate showed plasma-coating radicals, only substrate radicals were observed when PE was used as the substrate. The nature of radicals formed depends not only on the deposition method used but also on the substrate type.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1011377900516
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 13
    Electronic Resource
    Electronic Resource
    ESR and polarography of nitroazoles. 7. Anion-radicals of isomers of N-methyl-C-nitro-1,2,4-triazole (2000)
    Springer
    Chemistry of heterocyclic compounds 36 (2000), S. 157-165 
    Details
    ISSN: 1573-8353
    Keywords: N-methyl-C-nitro-1,2,4-triazoles ; anion-radicals ; quantum-chemical calculations ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The anion-radicals of N-methyl-substituted 3-nitro-1,2,4-triazole have been studied by polarography, ESR, and quantum-chemical methods. The difference in electrochemical behavior of the N-methyl isomers of 3-nitro-1,2,4-triazole has been analyzed. The spin distributions in their anion-radicals have been investigated by quantum-chemical methods. The theoretical data obtained are in poor agreement with experiment. By varying the structural characteristics of the anion-radicals internal geometric parameters have been separated out which prove to have the greatest effect on spin distributions. Geometric structures were established for the investigated isomers by minimizing the functional describing the disagreement of the theoretical and experimental spin distributions on the magnetic nuclei. The calculated hyperfine structure constants for the magnetically active nuclei for the structures obtained were in good agreement with experiment. The influence of solvation effects on the electronic structure parameters of the nitrotriazole anion-radicals has been investigated. Hydrated complexes containing four molecules of water proved to be the most stable. Structural deformation of the solvated anion-radicals occurs in the same direction as on minimizing the functional.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02283544
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 14
    facet.materialart.
    Unknown
    Methods and Applications of Inversion (2000)
    Springer
    In:  Berlin, 306 pp., Springer, vol. 2, no. XVI:, pp. 1-14, (ISBN: 0-387-30752-4)
    Details
    Publication Date: 2000
    Keywords: Textbook of geophysics ; Textbook of geology ; Textbook of mathematics ; Data analysis / ~ processing ; Modelling ; Inversion
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    BIBLIOGRAPHY SEISMOLOGY
  • 15
    facet.materialart.
    Unknown
    Geomatic Methods for the Analysis of Data in the Earth Sciences (2000)
    Springer
    In:  New York, Springer, vol. 31, no. 3, pp. 2-203, (ISBN 0-87590-533-1)
    Details
    Publication Date: 2000
    Keywords: Data analysis / ~ processing ; Error analysis ; Handbook of geophysics ; Handbook of geodesy ; toolbox ; Statistical investigations ; Inversion ; Non-linear effects ; aerial ; images ; Diffraction ; Tomography ; 1214 ; Geodesy ; and ; gravity ; Geopotential ; theory ; and ; determination ; 1224 ; Photogrammetry ; remote ; sensing ; 0902 ; Exploration ; geophysics ; Computational ; methods, ; seismic ; Gruen ; Grun
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    BIBLIOGRAPHY SEISMOLOGY
  • 16
    Electronic Resource
    Electronic Resource
    Is the inversion effect in rhesus monkeys face-specific? (1999)
    Springer
    Animal cognition 2 (1999), S. 123-129 
    Details
    ISSN: 1435-9456
    Keywords: Key words Face recognition ; Inversion ; Expertise ¶effect ; Matching-to-sample ;  Macaca mulatta
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract This study investigated the face inversion effect in rhesus monkeys (Macaca mulatta). Face stimuli consisted of ten black-and-white examples of unfamiliar rhesus monkey faces, brown capuchin faces, and human faces. Two non-face categories included ten examples of automobiles and abstract shapes. All stimuli were presented in a sequential matching-to-sample format using an automated joystick-testing paradigm. Subjects performed significantly better on upright than on inverted presentations of automobiles, rhesus monkey and capuchin faces, but not human faces or abstract shapes. These results are inconsistent with data from humans and chimpanzees that show the inversion effect only for categories of stimuli for which subjects have developed expertise. The inversion effect in rhesus monkeys does not appear to be face-specific, and should therefore not be used as a marker of specialized face processing in this species.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s100710050032
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 17
    Electronic Resource
    Electronic Resource
    ESR, FT-Raman spectroscopic and ethanol partial oxidation studies on MoO3/SnO2 catalysts made by metal oxide vapor synthesis (1999)
    Springer
    Catalysis letters 59 (1999), S. 73-77 
    Details
    ISSN: 1572-879X
    Keywords: MOVS ; MoO3/SnO2 ; characterization ; XRD ; ESR ; FT-Raman ; ethanol partial oxidation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract A series of SnO2-supported MoO3 catalysts were prepared by the metal oxide vapor synthesis (MOVS) technique. ESR studies indicated the presence of highly dispersed Mo5+ species in both octahedral and tetrahedral coordination environments at all the loadings studied. At the highest MoO3 loading of 12 wt%, the formation of MoO3 microcrystallites was indicated from the lower intensity of the ESR signal. Raman studies also showed the presence of well dispersed surface molybdate species up to 4.4 wt% MoO3 loading, and the peaks corresponding to microcrystallites of molybdena were observed at 12 wt% MoO3 loading. The ethanol partial oxidation activities of the catalysts increased with increase in MoO3 loading and the catalyst with 4.4 wt% molybdena content showed the highest activity; all the MOVS catalysts showed 100% selectivity to acetaldehyde at low conversions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1019099900418
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 18
    Electronic Resource
    Electronic Resource
    ESR as a fast technique to dissolve nitrogen-rich inclusions in titanium (1999)
    Springer
    Materials research innovations 2 (1999), S. 364-368 
    Details
    ISSN: 1433-075X
    Keywords: Key words Titanium ; Nitrogen-rich inclusions ; Titanium nitride ; TiN ; Hard-alpha ; Refining ; Electroslag refining ; ESR ; Ultrasonic inspection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract  Nitrogen-rich inclusions can lead to a reduction in fatigue life of highly stressed titanium-alloy components (found in the compressor sections of power generation gas turbines, turbine sections of power generation steam turbines, wing sections of aircraft air frames, and compressor and fan sections of aircraft jet engines, for example). It is the ”crack starting” nature of the nitrogen-rich inclusions that is the problem, not the presence of nitrogen in the system, per se. This paper covers the theory and laboratory experiments used to evaluate ESR (electro-slag refining) as an alternative technique for rapid dissolution of nitrogen-rich inclusions in titanium and titanium alloys. Five variations of melt rate, slag temperature and inclusion type were evaluated. One variant showed complete dissolution of the inclusions. Several of the other variants showed partial dissolution of the inclusions. The kinetics were observed to occur at a rate 100 to 1000 times faster than the rate of dissolution of nitrogen-rich inclusions by immersion in liquid titanium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s100190050115
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 19
    Electronic Resource
    Electronic Resource
    Energy Fluxes of an Open Water Area in a mid-Latitude Prairie Wetland (1999)
    Springer
    Boundary layer meteorology 91 (1999), S. 495-504 
    Details
    ISSN: 1573-1472
    Keywords: Evaporation ; Heat storage ; Marsh ; Inversion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract Concurrent measurements of the surface energy balance components (net radiation, heat storage, and sensible and latent heat fluxes) were made in three communities (open water, Phragmites australis, Scirpus acutus) in a wetland in north-central Nebraska, U.S.A., during May-October, 1994. The Bowen ratio – energy balance method was used to calculate latent and sensible heat fluxes. This paper presents results from the open water area. The heat stored in water (G) was found to play a major role in the energy exchange over the water surface. During daytime, G consumed 45–60% of R n , the net radiation (seasonally averaged daytime G was about 127 W m−2). At night, G was a significant source of energy (seasonally averaged nighttime G was about -135 Wm−). The diurnal pattern of latent heat flux (λ E) did not follow that of R n . On some days, λ E was near zero during midday periods with large R n . The diurnal variability in λ E seemed to be significantly affected by temperature inversions formed over the cool water surface. The daily evaporation rate (E) ranged from 2 to 8 mm during the measurement period, and was generally between 70 and 135% of the equilibrium rate.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1001802821846
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 20
    Electronic Resource
    Electronic Resource
    Molecular rearrangements of thylakoids after heavy metal poisoning, as seen by Fourier transform infrared (FTIR) and electron spin resonance (ESR) spectroscopy (1999)
    Springer
    Photosynthesis research 61 (1999), S. 241-252 
    Details
    ISSN: 1573-5079
    Keywords: ESR ; electron transport ; FTIR ; lipid ; membrane structure ; protein ; photosynthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The specific effects exerted by different heavy metals on both the function and the structure of the photosynthetic apparatus were addressed. The functional analysis performed via the fluorescence induction kinetics revealed that the applied toxic heavy metals can be classified into two groups: Cd and Ni had no significant effect on the photosynthetic electron transport, while Cu, Pb and Zn strongly inhibited the Photosystem II (PS II) activity, as evidenced by the dramatic decreases in both the variable (Fv) and the maximal (Fm) fluorescence. The structural effects of the heavy metal ions on the thylakoid membranes were considered in three relations: (1) lipids, (2) proteins — studied by Fourier transform infrared (FTIR) spectroscopy, and (3) lipid—protein interactions — investigated by electron spin resonance (ESR) spectroscopy using spin-labeled probe molecules. The studied heavy metal ions had only a non-specific rigidifying effect on the thylakoid lipids. As regards proteins, Cd and Ni had no effect on the course of their heat denaturation. The heat denaturation of the proteins was accompanied by a decrease in the α-helix content (1656 cm-1), a parallel increase in the disordered segments (1651 cm-1), a decrease in the intramolecular β-sheet (1636 cm-1) content and the concomitant appearance of an intermolecular β-structure (1621 cm-1). In contrast with Cd and Ni, Cu and Zn blocked the appearance of the intermolecular β-structure. Pb represented an intermediate case. It seems that these heavy metals alter the native membrane structure in such a way that heat-induced aggregation becomes more limited. The ESR data revealed that certain heavy metals also affect the lipid—protein interactions. While Cd and Ni had hardly any effect on the solvation fraction of thylakoid lipids, Cu, Pb and Zn increased the fraction of lipids solvating the proteins. On the basis of the FTIR and ESR data, it seems that Cu, Pb, and Zn increase the surfaces available for lipid—protein interactions by dissociating membrane protein complexes, and that these ‘lipidated’ proteins have a smaller chance to aggregate upon heat denaturation. The data presented here indicate that the damaging effects of poisonous heavy metals are element-specific, Cu, Pb and Zn interact directly with the thylakoid membranes of the photosynthetic apparatus, while Cd and Ni interfere rather with other metabolic processes of plants.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006345523919
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 21
    Electronic Resource
    Electronic Resource
    ESR study of reduced vanadium-titanium oxide catalysts (1999)
    Springer
    Reaction kinetics and catalysis letters 67 (1999), S. 273-279 
    Details
    ISSN: 1588-2837
    Keywords: Vanadium-titanium oxide catalyst ; reduction with hydrogen ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Reduction of vanadium-titanium oxide catalysts with hydrogen in the temperature range of 150–450°C results in the increase of the content of V4+ ions in substitution positions of TiO2 with the anatase structure. The temperature increase up to 250°C results in the growth of the spectral intensity of V4+ associates in substitution positions of anatase. At higher treatment temperatures their intensity decreases due to the formation of VO2 fragments in anatase. At 400°C and higher temperatures a solid solution of V4+ ions in rutile is formed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02475771
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 22
    Electronic Resource
    Electronic Resource
    Suppression of radical-cationic benzene oligomerization on sulfated zirconia (1999)
    Springer
    Reaction kinetics and catalysis letters 67 (1999), S. 197-203 
    Details
    ISSN: 1588-2837
    Keywords: Sulfated zirconia ; ESR ; cation radicals ; benzene ; biphenyl ; oligomerization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The effect of catalyst activation conditions on transformations of benzene cation radicals on sulfated zirconia has been studied by in situ ESR spectroscopy. After the catalyst activation at 300°C there was no oligomerization of the cation radicals to biphenyl and heavier products, which is observed after catalyst calcination at 500°C. It has been suggested that the oligomerization is suppressed by the presence of strong Brönsted sites on the surface.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02475848
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 23
    Electronic Resource
    Electronic Resource
    ESR study of paramagnetic sites in sulfated zirconia (1998)
    Springer
    Catalysis letters 56 (1998), S. 23-27 
    Details
    ISSN: 1572-879X
    Keywords: sulfated zirconia ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract ESR spectroscopy was used to investigate paramagnetic sites in sulfated zirconia. Catalysts derived from zirconium oxide and zirconium hydroxide were studied. It was demonstrated that paramagnetic sites assigned to near-surface F-centers were formed during activation at temperatures above 573 K. The catalyst derived from zirconium hydroxide shows after activation at 873 K two types of paramagnetic sites: F-centers and Zr3+ sites. Both F-centers and Zr3+ sites in this catalyst form complexes with reagents upon n-butane or hydrogen adsorption at range of 423–523 K in contrast to paramagnetic sites of the oxide-derived catalyst.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1019084323732
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 24
    Electronic Resource
    Electronic Resource
    In situ high-temperature ESR characterization of FeZSM-5 and FeSAPO-34 catalysts in flowing mixtures of NO, C3H6, and O2 (1998)
    Springer
    Catalysis letters 56 (1998), S. 173-181 
    Details
    ISSN: 1572-879X
    Keywords: ESR ; ferric ions ; FeZSM-5 ; ethane oxidation ; stability of isolated ferric ions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract In situ ESR of FeHZSM-5 shows that samples made by sublimation of FeCl3 contain mainly ferric ions in tetrahedral and distorted tetrahedral sites. Above 200°C these ions do not chemisorb water, which confirms the resistance to activity deterioration by water vapor claimed for FeHZSM-5, when used in SCR of NOx. The number of ESR-active Fe3+ ions decreases when moving from strongly oxidizing conditions towards stoichiometry at 500°C. In more reducing atmospheres, i.e., when excess reductant is present, the exposure produces an agglomerated ferromagnetic species, presumably magnetite. This process is irreversible. As the trivalent dispersed iron ions are the catalytically active sites, this transformation makes Fe-containing catalysts vulnerable to accidental but irreversible transformation induced by even mildly reducing conditions. The dispersion of ferric ions in FeSAPO-34 is not as good as in FeHZSM-5 and the reactive Fe3+ in distorted tetrahedral sites is absent. Catalytic oxidation of ethane allows correlation of the EPR results with activity and stability.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1019002322340
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 25
    Electronic Resource
    Electronic Resource
    Biophysical characterization of the interaction of bovine seminal plasma protein PDC-109 with phospholipid vesicles (1998)
    Springer
    European biophysics journal 27 (1998), S. 33-41 
    Details
    ISSN: 1432-1017
    Keywords: Key words Seminal plasma protein ; PDC-109 ; Membrane ; Fluorescence ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Physics
    Notes: Abstract PDC-109 is the major protein of bovine seminal plasma. It binds to the bovine sperm surface at ejaculation and modulates sperm capacitation. PDC-109 displays phosphorylcholine- and heparin-binding activities which are thought to account for its sperm surface coating and glycosaminoglycan-induced sperm capacitating activities, respectively. We have characterized the interaction of isolated PDC-109 with membranes of phospholipid vesicles using a biophysical approach. Our results show that PDC-109 interacts not only with the solvent-exposed phosphorylcholine head group but also with the hydrophobic core of liposomes. Binding of PDC-109 to membranes is a very rapid, biphasic process with half times of less than one second. Maximal binding of PDC-109 to small unilamellar vesicles was achieved with a stoichiometric ratio of 10–11 phosphatidylcholine molecules/PDC-109 molecule. Incorporation of phosphatidylethanolamine or phosphatidylserine into phosphatidylcholine vesicles reduced the binding of PDC-109, suggesting that both the density of phosphorylcholine groups and the surface charge determine the interaction of the seminal plasma protein with the surface of the membrane. Electron spin resonance measurements showed that binding of PDC-109 to phosphatidylcholine vesicles caused a rigidification of the membrane. The relevance of the data for describing the role of PDC-109 in the modulation of sperm capacitation is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002490050108
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 26
    Electronic Resource
    Electronic Resource
    Origin of free radicals produced from the syringyl end groups in lignins (1998)
    Springer
    Journal of wood science 44 (1998), S. 314-319 
    Details
    ISSN: 1611-4663
    Keywords: ESR ; Lignin ; Acidolysis ; Reduction ; Syringyl end group
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Enzyme lignin was prepared from reed; it was acid-hydrolyzed and reduced with NaBH4. Spin concentrations of radicals produced by oxidation of the lignins with K3[Fe(CN)6] or H2O2 were determined from electron spin resonance spectra. The radicals were observed by the oxidation of sinapyl alcohol. It was found that the two radicals observed by the oxidation of dioxane lignins were deprotonated 2,6-dimethoxyp-benzosemiquinone and 6-hydroxy-2-methoxy-p-benzosemiquinone, and that they were produced from syringyl end groups. The production rate of radicals from syringyl end groups possessing anα-carbonyl group was greater than that possessing anα-hydroxyl group. It was suggested that stilbene-type syringyl end groups were produced from phenylcoumaran moieties in lignins by acidolysis. The radicals produced from guaiacyl end groups were not observed by the oxidation process.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00581313
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 27
    Electronic Resource
    Electronic Resource
    Studies on the interactions between anionic surfactants and polyvinylpyrrolidone: Surface tension measurement, 13C NMR and ESR (1998)
    Springer
    Colloid & polymer science 276 (1998), S. 1-10 
    Details
    ISSN: 1435-1536
    Keywords: Key words Interaction ; anionic surfactant ; polyvinylpyrrolidone ; ESR ; NMR
    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 interaction between anionic surfactants and polyvinylpyrrolidone (PVP) are investigated using 13C NMR, ESR spectroscopy and surface tension measurements at the air/water interface. The behavior of single-chained surfactant, sodium dodecyl sulphonate (AS), is compared with that of the double-chained surfactant, sodium bis(2-ethylhexyl) phosphate (NaDEHP). The results showed that a surfactant–polymer complex of “necklace and head structure” is formed in AS aqueous solutions in the presence of PVP due to the hydrophobic interaction between PVP and AS. The AS micelles nucleate on the polymer hydrophobic sites, and the mobility of the AS head groups is not affected. But, for NaDEHP surfactant, it was found that PVP is little effective in influencing the monomer–micelle equilibrium and no surfactant– polymer complex formed in the NaDEHP aqueous solution.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003960050201
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 28
    Electronic Resource
    Electronic Resource
    Ruby ESR Over a Wide Frequency Range in the Millimeter Wave Region (1998)
    Springer
    International journal of infrared and millimeter waves 19 (1998), S. 859-874 
    Details
    ISSN: 1572-9559
    Keywords: ruby ; gyrotron ; ESR ; millimeter-wave
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The ESR of Cr3+ in dark ruby is measured using a high frequency ESR spectrometer with a wide frequency range which uses a gyrotron as the radiation source. For this purpose, GYROTRON FU- IV A developed at Fukui University was optimized for use in an ESR apparatus operating in the millimeter-wave range. The observed fine structure constant D for ruby is found to be D ∼−5.728 GHz and the g-values g∥ ∼1.981, g ⊥ ∼1.982. Both the values of |D| and g are smaller than those obtained at lower frequencies by other work. Higher order terms of the spin hamiltonian are discussed in order to understand the ruby ESR results in this higher frequency range.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1022628524439
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 29
    Electronic Resource
    Electronic Resource
    Cytotoxic peptides: Naphthoquinonyl derivatives of luteinizing hormone-releasing hormone (1998)
    Springer
    International journal of peptide research and therapeutics 5 (1998), S. 421-427 
    Details
    ISSN: 1573-3904
    Keywords: ESR ; LH-RH ; quinones ; solid phase synthesis ; targeted chemotherapy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary In an attempt to produce efficient cytotoxic derivatives of luteinizing hormone-releasing hormone (LH-RH), two novel 1,4-naphthoquinone derivatives of [d-Lys6]-LH-RH were synthesized primarily by solid-phase peptide synthesis, in good yield and high purity. The ability of each analog to produce reactive oxygen species using enzymatic reduction, i.e. NADPH-cytochrome P-450 reductase, was evaluated employing electron spin resonance (ESR) spectroscopy and spin-trapping techniques. The ESR results suggest that the novel cytotoxic analogs are extremely effective in generating oxygen radicals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02443499
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 30
    Electronic Resource
    Electronic Resource
    Cytotoxic Peptides: Naphthoquinonyl Derivatives of Luteinizing Hormone-Releasing Hormone (1998)
    Springer
    International journal of peptide research and therapeutics 5 (1998), S. 421-427 
    Details
    ISSN: 1573-3904
    Keywords: ESR ; LH-RH ; quinones ; solid phase synthesis ; targeted chemotherapy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract In an attempt to produce efficient cytotoxic derivatives of luteinizing hormone-releasing hormone (LH-RH), two novel 1,4-naphthoquinone derivatives of [D-Lys6]-LH-RH were synthesized primarily by solid-phase peptide synthesis, in good yield and high purity. The ability of each analog to produce reactive oxygen species using enzymatic reduction, i.e. NADPH-cytochrome P-450 reductase, was evaluated employing electron spin resonance (ESR) spectroscopy and spin-trapping techniques. The ESR results suggest that the novel cytotoxic analogs are extremely effective in generating oxygen radicals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008855430212
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 31
    facet.materialart.
    Unknown
    Inverse Problems in Engineering Mechanics - Proc. Internat. Symp. Inv. Probl. in Eng. Mech. (ISIP '98), March 1998, Nagano (1998)
    Elsevier
    In:  Amsterdam, Elsevier, vol. 1, no. ALEX(01)-FR-77-01, AFTAC Contract F08606-76-C-0025, pp. 95-104, (ISBN 1-85312-745-0)
    Details
    Publication Date: 1998
    Keywords: Inversion ; Elasticity ; Geothermics ; Scattering ; soil ; Modelling ; Fluids ; Acoustics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    BIBLIOGRAPHY SEISMOLOGY
  • 32
    Electronic Resource
    Electronic Resource
    Radical reactions of N-heterocyclic compounds, XV. Radial intermediates and end products of the oxidation of 3-anilino-1,5-diphenylpyrazoles with Pb(OAc)4 (1997)
    Springer
    Monatshefte für Chemie 128 (1997), S. 261-270 
    Details
    ISSN: 1434-4475
    Keywords: Aminyl radicals ; ESR ; NMR ; Pyrazoles ; Triarylaminium cation radicals
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die substituierten 3-Anilino-1,5-diphenylpyrazole1a–i wurden mit Pb(OAc)4 in Benzol oder CH2Cl2 oxidiert. Die intermediären Aminylradikale3f–i wurden ESR-spektroskopisch bei der Oxidation der im Anilinrest methylsubstituierten Pyrazole1f–i nachgewiesen. Die ESR-spektroskopisch nach Oxidation der Pyrazole1a–e beobachteten Radikalintermediate interpretieren wir als Kationradikale6a–e. Diese werden durch Weiteroxidation der Dimeren4a–e gebildet, deren Struktur durch NMR-Untersuchungen und15N-Markierung bewiesen wurde.
    Notes: Summary Substituted 3-anilino-1,5-diphenylpyrazoles1a–i were oxidized with Pb(OAc)4 in benzene or CH2Cl2 solution. The ESR measurements confirmed the formation of aminyl radicals3f–i frompara-CH3 substituted pyrazoles1f–i. The radical intermediates from unsubstituted pyrazoles1a–e were assigned to triarylaminium cation radicals These were generated by consecutive oxidation of the dimeric products4a–e whose structure was proven by NMR spectroscopy and15N labeling.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00807892
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 33
    Electronic Resource
    Electronic Resource
    Running programs backwards: The logical inversion of imperative computation (1997)
    Springer
    Formal aspects of computing 9 (1997), S. 331-348 
    Details
    ISSN: 1433-299X
    Keywords: Inversion ; Abduction ; Reverse computation ; Program testing ; Logic programming
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Notes: Abstract Imperative programs can be inverted directly from their forward-directed program code with the use of logical inference. The relational semantics of imperative computations treats programs as logical relations over the observable state of the environment, which is taken to be the state of the variables in memory. Program relations denote both forward and backward computations, and the direction of the computation depends upon the instantiation pattern of arguments in the relation. This view of inversion has practical applications when the relational semantics is treated as a logic program. Depending on the logic programming inference scheme used, execution of this relational program can compute the inverse of the imperative program. A number of nontrivial imperative computations can be inverted with minimal logic programming tools.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01211087
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 34
    Electronic Resource
    Electronic Resource
    Expansion of the IR in the chloroplast genomes of buckwheat species is due to incorporation of an SSC sequence that could be mediated by an inversion (1997)
    Springer
    Current genetics 31 (1997), S. 276-279 
    Details
    ISSN: 1432-0983
    Keywords: Key words Buckwheat ; Chloroplast DNA ; Inversion ; Inverted repeats
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The chloroplast genomes in buckwheat species contain large inverted repeats which are at least 4 kbp longer than the majority of those in land plants. The length of the buckwheat inverted repeats was attributable to an additional region located adjacent to the borders of the small single-copy region. We have cloned and sequenced a 5.2-kbp SmaI fragment corresponding to this extra region in the inverted repeats. A homology search revealed that the sequence of the SmaI fragment is highly homologous to one side of the small single-copy region of the inverted repeats in dicot chloroplast DNAs such as tobacco and beechdrops. Interestingly, a 3.7-kbp segment in the middle of the SmaI fragment is inserted in the opposite orientation relative to those of the other dicot species, and 17-bp direct repeats are found located at both the ends of the additional region. These results suggest that expansion of the inverted repeats in buckwheat chloroplast DNA might have been associated with an inversion.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002940050206
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 35
    Electronic Resource
    Electronic Resource
    ESR Study of a Nitroxide Radical in Sol-Gel Glasses (1997)
    Springer
    Journal of sol gel science and technology 9 (1997), S. 273-277 
    Details
    ISSN: 1573-4846
    Keywords: silica ; TEPOL ; ESR ; doped sol-gel ; TEOS
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract A spin probe TEMPOL (4-hydroxy-2,2,6,6-tetramethylpiperidinyl-1-oxy) was dissolved in a tetraethyl orthosilicate sol-gel reaction system and measured by electron spin resonance spectroscopy at 295 K. The nitrogen hyperfine coupling constant was from 1.64–1.66 mT in the sol-gel solutions. The values were sensitive to the ethanol-to-water ratio of the solutions. The hyperfine coupling constant in the xerogels was 1.70 mT, which was almost the same as that in water, indicating that the probe molecules were trapped in silica pores with water adsorbed on the silica surfaces. The motion of TEMPOL in the xerogels was considerably slower than in the sol-gel solutions. The local viscosity estimated was from 70–90 cP. The ESR spectra of TEMPOL were altered during the sol-gel process, indicating that adsorbed water on the silica surfaces has an important role for trapping organic molecules in sol-gel glasses.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1018359311661
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 36
    Electronic Resource
    Electronic Resource
    ESR study of a nitroxide radical in sol-gel glasses (1997)
    Springer
    Journal of sol gel science and technology 9 (1997), S. 273-277 
    Details
    ISSN: 1573-4846
    Keywords: silica ; TEPOL ; ESR ; doped sol-gel ; TEOS
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract A spin probe TEMPOL (4-hydroxy-2,2,6,6-tetramethylpiperidinyl-1-oxy) was dissolved in a tetraethyl orthosilicate sol-gel reaction system and measured by electron spin resonance spectroscopy at 295 K. The nitrogen hyperfine coupling constant was from 1.64–1.66 mT in the sol-gel solutions. The values were sensitive to the ethanol-to-water ratio of the solutions. The hyperfine coupling constant in the xerogels was 1.70 mT, which was almost the same as that in water, indicating that the probe molecules were trapped in silica pores with water adsorbed on the silica surfaces. The motion of TEMPOL in the xerogels was considerably slower than in the sol-gel solutions. The local viscosity estimated was from 70–90 cP. The ESR spectra of TEMPOL were altered during the sol-gel process, indicating that adsorbed water on the silicas surfaces has an important role for trapping organic molecules in sol-gel glasses.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02437190
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 37
    Electronic Resource
    Electronic Resource
    ESR Dosimetry of Irradiated Ascorbic Acid (1997)
    Springer
    Pharmaceutical research 14 (1997), S. 1186-1191 
    Details
    ISSN: 1573-904X
    Keywords: radiosterilization ; ascorbic acid ; ESR ; dosimetry ; decay of radicals
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Purpose. As an alternative to heat and gas exposure sterilization, ionizing radiation is gaining interest as a sterilization process for medicinal products. The aim of this work was to develop equations to describe the ESR curves versus dose and storage time after gamma irradiation of ascorbic acid. Several ESR data sets previously acquired in this laboratory were adopted to check the performance of the models. Results. Limit of detection and limit of discrimination are respectively 0.5 kGy and 2 kGy for ascorbic acid. Linear regression is applicable for doses lower than 25 kGy. Since the radiation dose selected must always be based upon the bioburden of the products and the Degree of Sterility required (ANSI/AAMI/ISO 11137), doses in the range 5−25 kGy could be investigated and linear regression would appear to be the least expensive route to follow and gives good results. Quadratic fit, power function, exponential function and bi-exponential functions are of more general applicability to predict irradiation dose. Decay kinetics for radicals versus storage were considered. Nonhomogeneous kinetics with time-dependent rate (diffusion-controlled second-order reaction) and bi-exponential function appeared valid to reproduce the experimental data. Discrimination between irradiated and unirradiated ascorbic acid is possible after a storage of 800 days. Conclusions. It is worth noting that, at present, ESR is the only technique which proves to be suitable for identification and quantification purposes in irradiated pharmaceuticals. Moreover, other features such as sensitivity, precision, ease and non-destructive readout make ESR superior to other proposed analytical techniques.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1012102806800
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 38
    Electronic Resource
    Electronic Resource
    Darstellung und Eigenschaften einiger Salze desBis(benzylmalonato)aquaoxovanadium(IV)-Anions (1996)
    Springer
    Monatshefte für Chemie 127 (1996), S. 801-810 
    Details
    ISSN: 1434-4475
    Keywords: Vanadyl(IV). Benzylmalonato complex ; IR ; Raman ; ESR ; Electronic spectra ; Thermal behaviour
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary The sodium, ammonium, and lead(II) salts of the novel vanadyl(IV) complex bis(benzylmalonato)aquaoxovanadium(IV) have been prepared for the first time. They were characterized by means of electronic, IR, Raman and ESR spectroscopy. The thermal behaviour of the salts was investigated using TG and DTA methods.
    Notes: Zusammenfassung Die Natrium-, Ammonium- und Blei(II)-Salze des neuen Vanadyl(IV)-KomplexesBis(benzylmalonato)aquaoxovanadium(IV)wurden erstmalig dargestellt und mittels Elektronen-, IR-, Raman- und ESR-Spektroskopie characterisiert. Das thermische Verhalten dieser Salze wurde anhand von TG- und DTA-Messungen untersucht.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00807019
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 39
    Electronic Resource
    Electronic Resource
    n-butane isomerization on sulfated zirconia. Deactivation and regeneration as studied by Raman, UV-VIS diffuse reflectance and ESR spectroscopy (1996)
    Springer
    Catalysis letters 36 (1996), S. 59-68 
    Details
    ISSN: 1572-879X
    Keywords: zirconia-sulfated ; n-butane ; isomerization ; deactivation ; regeneration ; Raman spectroscopy ; UV-VIS diffuse reflectance ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract n-butane isomerization on sulfated zirconia was studied in the temperature range 393–473 K. Rapid deactivation occurs, when the reaction is carried out in He carrier gas. In contrast, stable stationary activity was observed in H2 carrier gas. In situ Raman and UV-VIS diffuse reflectance spectroscopy and ESR showed that the deactivation is caused by the formation of allylic and polyenylic cations and polycyclic aromatic compounds, the formation of which is largely prevented in the presence of H2. Deactivated catalysts can be fully regenerated by treatment at 723–753 K in flowing O2. The regeneration process was also followed by in situ spectroscopies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00807206
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 40
    Electronic Resource
    Electronic Resource
    Inversion of a transfer system into lateral ramps: An example from the South-Central Pyrenees (Spain) (1996)
    Springer
    International journal of earth sciences 85 (1996), S. 372-379 
    Details
    ISSN: 1437-3262
    Keywords: Pyrenees ; Cadí ; Nogueres ; Inversion ; Lateral ramps ; Transfer faults ; Tear faults
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract Field work in the South-Central Pyrenees suggests that omission contacts (i.e. younger over older rocks) occur at the base of the Cadí unit (Cadí thrust), and pass laterally into thrusts. This change occurs across tear faults which are present in the hangingwall of the Cadí thrust sheet and which controlled the deposition of Upper Cretaceous sediments (Adraén formation). Detailed mapping in the contact area between the Nogueres and Cadí units has shown that the actual thrust geometry in the study area is controlled by preexisting normal and transfer faults which developed in an already compressional context. Lateral ramps or tear faults develop depending on the angle between the pre-existing extensional transfer fault and the thrust transport direction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02422242
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 41
    Electronic Resource
    Electronic Resource
    Kinetics of O2 + TEOS gas-phase chemical reactions in a remote RF plasma reactor with electron spin resonance (1996)
    Springer
    Plasma chemistry and plasma processing 16 (1996), S. 187-194 
    Details
    ISSN: 1572-8986
    Keywords: TEOS ; ESR ; rate coefficients ; remote microwave discharge
    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 Kinetics of the reaction O+TEOS (tetraethoxysilane) was studied by means of the ESR method. Molecular oxygen was partially atomized by a 13.56-MHz discharge in the quartz tube that passed inside an ESR cavity. TEOS vapors were injected between the discharge and ESR cavity. O-atom loss occurring due to the reaction of atomic oxygen with TEOS molecules was measured and the rate coefficient k, of the reaction of O atoms with TEOS molecules was determined. The obtained results could be used for deposition process simulations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01570177
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 42
    Electronic Resource
    Electronic Resource
    Preparation and characterization of a biologically active spin-labeled sea anemone toxin (1996)
    Springer
    The protein journal 15 (1996), S. 427-434 
    Details
    ISSN: 1573-4943
    Keywords: Anthopleurin ; spin label ; multiple conformers ; aggregation ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract A derivative of the polypeptide cardiostimulant anthopleurin-B(AP-B) labeled with the spin label 1-oxyl 2,2,6,6-tetramethyl-4-piperidinyloxycarbonyl azide has been prepared and characterized. The product was found by mass spectrometry to be labeled at a single site, which amino acid sequencing showed to be the N-terminus. It also retained positive inotropic activity when assayed on isolated guinea pig atria. The spin-labeled (SL) product was found to exist in two distinct conformations by reversed-phase HPLC and in at least two conformations by electron spin resonance spectroscopy (ESR) over thepH range 2–9. The ESR data also show evidence for multimetric states of SL-AP-B over thepH range 2–9, with maximum aggregation at pH 4.5–5, and a slow disaggregation when thepH is adjusted to 8–9. The presence of multiple conformers of SL-AP-B and its tendency to aggregate render it unsuitable for high-resolution NMR structural studies of the isolated ligand, but the retention of activity may make it useful for studies of the sodium-channel-bound form of the molecule.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01886849
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 43
    Electronic Resource
    Electronic Resource
    An ESR study of radical reactions of C60 and C70 (1996)
    Springer
    Russian chemical bulletin 45 (1996), S. 2267-2278 
    Details
    ISSN: 1573-9171
    Keywords: fullerene ; ESR ; radicals ; structure ; reactivity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The results of ESR spectroscopic studies of radical reactions of fullerenes are presented. Reactivities of radicals of various chemical natures with respect to C60 and C70, delocalization of the unpaired electron in monofullerenyl radicals, and their reactivity are considered. The examples of dynamic effects in the ESR spectra of fullerenyl radicals, associated with the hindered rotation of the attached radicals, are presented. Characteristic features of the structures of the spin adducts resulting from polyaddition of free radicals to fullerenes and of fullerenyl radicals containing η2-bonded metaIloco mplexes are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01435367
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 44
    Electronic Resource
    Electronic Resource
    ESR study of spin-adducts of dialkoxyphosphoryl radicals with di(p-methoxyphenyl)methanofullerene (1996)
    Springer
    Russian chemical bulletin 45 (1996), S. 2865-2867 
    Details
    ISSN: 1573-9171
    Keywords: ESR ; diarylmethanofullerene ; fullerenyl radical ; isomers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The addition of phosphoryl radicals to C60C(p-C6H4OMe)2 was shown (ESR) to result in the formation of at least seven isomers differing in their hyperfine coupling constants (HFC) with the phosphorus nuclei and in their kinetic behavior and thermodynamic stability.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01430664
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 45
    Electronic Resource
    Electronic Resource
    Homobinuclear bis-3,6-di-tert-butyl-o-benzosemiquinone and bis-3,6-di-tert-butyl-o-catecholate complexes of PdII and PtII with bridging ligands. Molecular structure of (3,6-Cat)2Pd2L2 (L = dppm and dppy) (1996)
    Springer
    Russian chemical bulletin 45 (1996), S. 446-450 
    Details
    ISSN: 1573-9171
    Keywords: ESR ; biradical ; semiquinone ; metal-metal bond ; X-ray structural analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Reactions of the binuclear complexes M2L2Cl2 [M = Pt or Pd, L = bis(diphenylphosphino)methane (dppm) or 2-(diphenylphosphino)pyridine (dppy)] with thallium 3,6-ditert-butyl-o-benzosemiquinone (3,6-SQ) in solutions have been studied. The formation of the corresponding bis(semiquinone) binuclear derivatives M2L2(SQ)2 with retention of the metal-metal bond has been established by the ESR method. The average distances between the centers of localization of unpaired electrons, which were determined from the ESR spectral data for the complexes studied, allow conclusions about the parallel arrangement of the semiquinone ligands in skewed conformations in a square-pyramidal coordination sphere of both metal atoms. At room temperature, the biradical complexes are slowly converted to diamagnetic catecholate compounds with cleavage of the M-M bond and with retention of the bridging structure of the dppm and dppy ligands. The structures of catecholate complexes of palladium have been established by X-ray structural analysis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01433992
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 46
    Electronic Resource
    Electronic Resource
    Mechanisms of processes involving β-substituted cyclopropyl radicals. Ring expansion in the reaction with CO (1996)
    Springer
    Russian chemical bulletin 45 (1996), S. 477-479 
    Details
    ISSN: 1573-9171
    Keywords: β-substituted cyclopropyl radicals ; ESR ; reactivity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The reaction of β-substituted cyclopropyl radicals with CO was studied by ESR. Tile acyl radical resulting from the addition of CO to the cyclopropyl radical was detected. At temperatures near 270 K, an intramolecular rearrangement of the acyl radical affords substituted 2-oxocyclobutyl radicals (ring expansion reaction). Mechanisms for the free-radical transformations studied were suggested.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01434002
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 47
    Electronic Resource
    Electronic Resource
    ESR spectra of γ-irradiated samples of iron(iii) binuclear complexes (1996)
    Springer
    Russian chemical bulletin 45 (1996), S. 824-826 
    Details
    ISSN: 1573-9171
    Keywords: binuclear iron(iii) complexes ; γ-irradiation ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract γ-Irradiation of μ-oxo-bridged binuclear iron complexes FeIII 2OL n in a glycerol or dimethylformamide matrix at 77 K affords unstable mixed-valence FeIIFIII forms resulting from the transfer of a mobile electron generated by the ionizing radiation. These nonequilibrium forms retain the ligand environment of the original complexes, and their ESR spectra at 77–200 K are characterized by an asymmetric signal with an axially anisotropicg-factor, which is in agreement with the spectra of the FeIIFe syu forms obtained by chemical reduction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01431305
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 48
    Electronic Resource
    Electronic Resource
    Molecular structure of mixed adsorption layers surfactant—polymer at a liquid—liquid interface (1996)
    Springer
    Russian chemical bulletin 45 (1996), S. 1563-1571 
    Details
    ISSN: 1573-9171
    Keywords: liquid-liquid interfaces ; ESR ; spin probe ; polymer adsorption ; sodium dodecyl sulfate ; surface potential ; electrokinetic potential
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Isotherms of the binding of dodecyl sulfate anions (DDS−)and Na+ counterions during their coadsorption with a nonionic polymer. proxanol (PR). at the interface of dodecane-water emulsions have been measured by conductometry and Na-selective potentiometry. The adsorption of DDS− and PR is concurrent. The affinity constant of PR to the interface determined by the Langmuir model decreases as the concentration of PR increases, and the surface concentration of DDS− tends to a nonzero limiting value at high concentrations of PR. The surface (ϕo) and electrokinetic (ζ) potentials at the interface have been determined at various polymer concentrations by the spin probe and electrophoresis methods. The average dielectric permeability and density of polymer segments in We adsorption layer have been determined by ESR. The lower boundary of the hydrodynamic thickness of the polymer adsorption layer at the interface has been estimated from the dependences of ϕo and ζ on the ionic strength.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01431787
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 49
    Electronic Resource
    Electronic Resource
    Inversion of a transfer system into lateral ramps: an example from the South-Central Pyrenees (Spain) (1996)
    Springer
    Geologische Rundschau 85 (1996), S. 372-379 
    Details
    ISSN: 0016-7835
    Keywords: Key words Pyrenees ; Cadí ; Nogueres ; Inversion ; Lateral ramps ; Transfer faults ; Tear faults
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract  Field work in the South-Central Pyrenees suggests that omission contacts (i.e. younger over older rocks) occur at the base of the Cadí unit (Cadí thrust), and pass laterally into thrusts. This change occurs across tear faults which are present in the hangingwall of the Cadí thrust sheet and which controlled the deposition of Upper Cretaceous sediments (Adraén formation). Detailed mapping in the contact area between the Nogueres and Cadí units has shown that the actual thrust geometry in the study area is controlled by pre-existing normal and transfer faults which developed in an already compressional context. Lateral ramps or tear faults develop depending on the angle between the pre-existing extensional transfer fault and the thrust transport direction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s005310050082
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 50
    Electronic Resource
    Electronic Resource
    Magneto-optical measurements with a hybrid magnet (1996)
    Springer
    International journal of infrared and millimeter waves 17 (1996), S. 1851-1857 
    Details
    ISSN: 1572-9559
    Keywords: Far-infrared spectrometer ; high magnetic field ; Hybrid magnet ; CuGeO3 ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract An FFT spectrometer has been constructed to measure magneto-optical spectra in the far-infrared region (3 to 40 cm−1) with a hybrid magnet system. The magneto-absorption was studied in the spin-Peierls cuprate CuGeO3 at various magnetic fields. Coil constants of superconducting magnet and resistive one, of which a hybrid magnet consists, were calibrated by ESR spectra at the constant field.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02069459
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 51
    Electronic Resource
    Electronic Resource
    Electron spin resonance analysis of paramagnetic Pd(I) species in Pd(II)-exchanged H-rho zeolite (1996)
    Springer
    Reaction kinetics and catalysis letters 57 (1996), S. 311-321 
    Details
    ISSN: 1588-2837
    Keywords: Zeolite ; Pd(I) ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Zeolite rho was synthesized and Pd(II) exchanged into it. Pd(II) was reduced to paramagnetic Pd(1) by a thermal activation process. The interactions of Pd(I) in zeolite H-rho with oxygen, water, methanol, ammonia, carbon monoxide and ethylene have been studied by electron spin resonance (ESR) and electron spin echo modulation (ESEM) spectroscopies. The ESR spectrum of an activated sample shows the formation of one Pd(I) species. Pd(I) interacts with water vapor or molecular oxygen to form Pd(II)−O2, indicating decomposition of water. Equilibration with methanol results in a broad isotropic ESR signal which is attributed to the formation of small palladium clusters. ESEM shows that the Pd clusters coordinate one molecule of methanol. Adsorption of ammonia produces a Pd(I) complex containing four molecules of ammonia based upon resolved nitrogen superhyperfine coupling. Adsorption of carbon monoxide results in a Pd(I) complex containing two molecules of carbon monoxide based upon resolved13C superhyperfine coupling. ESR and ESEM results indicate that exposure to ethylene leads to two new Pd(I) species each of which coordinates one molecule of ethylene.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02064745
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 52
    Electronic Resource
    Electronic Resource
    Novel naphthoquinonyl derivatives: Potential structural components for the synthesis of cytotoxic peptides (1996)
    Springer
    International journal of peptide research and therapeutics 3 (1996), S. 263-274 
    Details
    ISSN: 1573-3904
    Keywords: Cytotoxic peptides ; ESR ; Reactive oxygen species ; Targeted chemotherapy ; Quinones
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Syntheses and physicochemical properties are described of several novel naphthoquinonyl amino acid derivatives, which are potential components in cytotoxic peptide conjugates. These compounds include N ε- and N α-naphthoquinonyl derivatives of lysine as well as N-naphthoquinonyl-carboxylic derivatives. The former class of compounds can be employed as building blocks in a stepwise peptide synthesis, whereas the latter two are adequate for postpeptide chain-assembly modifications. The ability of the naphthoquinonyl derivatives to produce semiquinone radicals and hydroxyl radicals (•OH), using chemical (i.e. NaBH4) and enzymatic (i.e. NADPH-cytochrome P-450 reductase) routes, respectively, was evaluated employing electron spin resonance spectroscopy.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00127660
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 53
    Electronic Resource
    Electronic Resource
    An ESR study of the products of multiple addition of diisopropoxyphosphoryl radicals to C60 (1996)
    Springer
    Russian chemical bulletin 45 (1996), S. 2538-2541 
    Details
    ISSN: 1573-9171
    Keywords: fullerene ; ESR ; phosphoryl ; multiple addition ; electron delocalization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The ESR spectra of the radicals resulting from the multiple addition of diisopropoxyphosphoryl radicals to C60 have been studied. The formation of six different types of radical adducts was detected. A structure for the stable product, characterized by hyperfine coupling of the unpaired electron with two phosphorus nuclei, was proposed. The unpaired electron in C60P(O)(OPri)2 is delocalized in the same way as in alkylfullerenyl radicals,i.e., mainly over the two six-membered rings adjacent to the C-CP(O)(OPri)2 bond.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01431111
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 54
    Electronic Resource
    Electronic Resource
    Structural evolution of wheat chromosomes 4A, 5A, and 7B and its impact on recombination (1995)
    Springer
    Theoretical and applied genetics 91 (1995), S. 282-288 
    Details
    ISSN: 1432-2242
    Keywords: Crossing-over ; Genetic map ; Inversion ; Linkage ; Recombination ; T. aestivum ; T. monococcum ; Translocation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The construction of comparative genetic maps of chromosomes 4Am and 5Am of Triticum monococcum and chromosomes of homoeologous groups 4, 5 and 7 of T. aestivum has provided insight into the evolution of these chromosomes. The structures of chromosomes 4A, 5A and 7B of modern-day hexaploid bread wheat can be explained by a 4AL/5AL translocation that occurred at the diploid level and is present both in T. monococcum and T. aestivum. Three further rearrangements, a 4AL/7BS translocation, a pericentric inversion and a paracentric inversion, have taken place in the tetraploid progenitor of hexaploid wheat. These structural rearrangements and the evolution of chromosomes 4A, 5A and 7B of bread wheat are discussed. The presence of the 4AL/5AL translocation in several Triticeae genomes raises two questions — which state is the more primitive, and is the translocation of mono- or poly-phylogenetic origin? The rearrangements that have occurred in chromosome 4A resulted in segments of both arms having different positions relative to the telomere, compared to 4Am and to 4B and 4D. Comparisons of map length in these regions indicate that genetic length is a function of distance from the telomere, with the distal regions showing the highest recombination.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00220890
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 55
    Electronic Resource
    Electronic Resource
    β-Substituted cyclopropyl rádicals grafted to silica surface. Methods of preparation, structure, and properties (1995)
    Springer
    Russian chemical bulletin 44 (1995), S. 2303-2315 
    Details
    ISSN: 1573-9171
    Keywords: β-substituted cyclopropyl radicals ; ESR ; reactivity ; quantum-chemical calculations
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Cyclopropyl type radicals $$X - _\triangledown \cdot (X = \begin{array}{*{20}c} \backslash \\ --- \\ / \\ \end{array} C, \begin{array}{*{20}c} \backslash \\ --- \\ / \\ \end{array} Si, \begin{array}{*{20}c} \backslash \\ --- \\ / \\ \end{array} Si---O)$$ were identified on a surface of activated silica by ESR. The possibility of their preparation by two methods,i.e., by photocyclization of substituted allyl radicals and by interaction of cyclopropane molecules with particular surface defects, was demonstrated. The effects of β-substituents on radiospectroscopic characteristics and thermal stabilities of the radicals were studied. Rate constants and activation energies of decomposition of substituted cyclopropyl radicals were estimated. The experimental data obtained were compared with the results of quantum-chemical calculations of model systems. The mechanism of photocyclization of allyl radicals was discussed. The transition states of decomposition of cyclopropyl and β-fluorine-substituted cyclopropyl radicals were calculated. Electronegative substitution was found to result in a considerable decrease in the activation energy of the cyclopropane ring opening.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00713599
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 56
    Electronic Resource
    Electronic Resource
    ESR and quantum-chemical studies of the structure and thermal transformations of vinylcyclopropane radical cations in irradiated frozen Freon matrices. Simulation of radical processes in the gas phase (1995)
    Springer
    Russian chemical bulletin 44 (1995), S. 203-227 
    Details
    ISSN: 1573-9171
    Keywords: radiolysis ; Freon matrices ; vinylcyclopropane ; primary radical cations ; distonic radical cations ; dimerization ; thermal rearrangements ; stereoelectronic control ; gas phase ; quantum-chemical analysis ; ESR ; MNDO-UHF
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Thermal trasfomations of vinylcyclopropane (VCP) radical cations (RC) in X-ray irradiated frozen Freon matrices, CFCl2CF2Cl and CFCl3, were studed by ESR. Radical processes involving VCP.+ in very rarefied and moderately thickened gaseous VCP were simulated. Monomolecular cleavage of the cyclopropane ring ofgauche-VCP.+ (1) occurs to give the more thermally stable distonic radical cationdist(0.90)-C5H8 .+ (3). As the density of VCP increases RC3 adds at the double bond ofanti-VCP to give the distonic RC,.CH2CH2CHCH(CH2)3CHCHCH2 + (5). Under the same conditions, the less thermally stableanti-VCP.+(2) undergoes monomolecular isomerization into RC1 or reacts withanti-VCP with the rearrangement (as in the condensed phase) to give its distonic form,dist(90.0)-C5H8 .+ (4). The MNDO-UHF method was adapted for quantum-chemical analysis of the constants of isotropic hyperfine coupling with1H and13C nuclei in neutral and charged hydrocabon radicals, since the standard version of this method inadequately reproduces the structural parameters of low-symmetry (C 1,C s) paramagnetic species. A quantum-chemical analysis of the radiospectroscopic information and of the stereoelectronic control of thermal transformations of conformers of RC1 and2 into their structurally nonequivalent distonic forms3 and4, respectively, was carried out.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00702125
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 57
    Electronic Resource
    Electronic Resource
    Doping mechanism of C60 fullerene by sodium and potassium (1995)
    Springer
    Russian chemical bulletin 44 (1995), S. 2096-2101 
    Details
    ISSN: 1573-9171
    Keywords: fullerene ; ESR ; conductivity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract ESR spectra of localized states of KC60 and K2C60 and conducting electrons of K3C60 were recorded in the process of doping C60 by potassium. The ESR spectra of K x C60 (x 〈 3) and Na x C60 correspond to the semiconductive state of the samples.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00696711
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 58
    Electronic Resource
    Electronic Resource
    ESR spectrometer with a wide frequency range using a gyrotron as a radiation power source (1995)
    Springer
    International journal of infrared and millimeter waves 16 (1995), S. 293-305 
    Details
    ISSN: 1572-9559
    Keywords: gyrotron ; ESR ; wide frequency range
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The development of a high frequency electron spin resonance (ESR) spectrometer with a wide frequency range using a gyrotron as the radiation power source is described. GYROTRON FU-E, optimized for use in an ESR spectrometer in the millimeter wave range, was developed in Fukui University. In order to test the normal operation of the spectrometer, the ESR of two standard samples, single crystal and polycrystalline DPPH, has been measured, in the pulsed mode over the frequency range from 65 GHz to 135 GHz.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02085864
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 59
    Electronic Resource
    Electronic Resource
    ESR study of formation of allylic radicals in simultaneous photochemical generation of phosphoryl and carbon-centered radicals in the presence of C60 fullerene (1995)
    Springer
    Russian chemical bulletin 44 (1995), S. 2316-2318 
    Details
    ISSN: 1573-9171
    Keywords: fullerene ; ESR ; allylic radical ; phosphoryl
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Allylic radicals resulting upon simultaneous photochemical generation of phosphoryl [.P(O)(OPri)2] and carbon-centered [.C(O)OMe,.CH3,.CCl3] radicals in saturated toluene solutions of C60 have been studied by the ESR method. The donor-acceptor properties of carbon-centered radicals determine the positions of phosphoryl groups in the allylic system.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00713600
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 60
    Electronic Resource
    Electronic Resource
    Structure of the blue forms of bisphthalocyanines of rare-earth elements (1995)
    Springer
    Russian chemical bulletin 44 (1995), S. 410-415 
    Details
    ISSN: 1573-9171
    Keywords: bisphthalocyanines ; rare-earth elements ; synthesis ; absorption spectra ; ESR ; X-ray photoelectron spectroscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Using electron spectroscopy, X-ray photoelectron spectroscopy, and ESR spectroscopy, the blue forms of bisphthalocyanines of rare-earth elements were found to have structures of sandwich-type complexes with isoelectronic phthalocyanine ligands linked with tetravalent metal ions, [Pc2−Ln4+Pc2−]0. A comparative spectral and electrochemical study of the blue and green forms oftert-butyl-substituted bisphthalocyanines was carried out for almost the whole series of rare-earth metals. Lutetium octa(perfluoro-tert-butyl)- and perchlorobisphthalocyanines were synthesized for the first time.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00702376
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 61
    Electronic Resource
    Electronic Resource
    ESR study of spin-adducts of boron-centered carboranyl radicals with fullerene-60 and fullerene-70 (1995)
    Springer
    Russian chemical bulletin 44 (1995), S. 1771-1772 
    Details
    ISSN: 1573-9171
    Keywords: fullerene, boron-centered carboranyl radical, spin-adducts ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Spin-adducts of boron-centered radicals, derivatives ofm-carboran-12, with fullerenes C60 and C70 have been studied by ESR spectroscopy. Constants of hyperfine splitting (HFS) of an unpaired electron with10B and11B nuclei have been determined from the ESR spectra of C60-B10H9C2H2 radicals. Three isomeric spin-adducts were detected with different HFS constants with11B, andg-factors were detected in the reaction of B10H9C2H2 with C70.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01151311
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 62
    Electronic Resource
    Electronic Resource
    Elektronen-Spin-Resonanz-Messungen an Trockenfrüchten (1994)
    Springer
    European journal of nutrition 33 (1994), S. 258-266 
    Details
    ISSN: 1436-6215
    Keywords: ESR ; HPLC ; Lebensmittelbestrahlung ; Trockenfrüchte ; Kohlenhydrate ; ESR ; HPLC ; food irradiation ; dried fruits ; sugars
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Medicine
    Description / Table of Contents: Summary While in a previous work the ESR spectroscopic detection of irradiated dried fruits was reported, in this paper liquid chromatographic determination of the carbohydrate fraction of these fruits is introduced and connected with the ESR results. After irradiation of dried fruits three different types of ESR spectra are observed. In most cases the dried fruits can be attached to these various types by means of their sugar composition. It was also found that the ESR spectra observed for sucrose-rich fruits are very similar to that of pure sucrose. The structure of the ESR spectra can change with storage. Probably, radical rearrangement reactions in the samples are responsible for these changes.
    Notes: Zusammenfassung Nachdem in einer früheren Arbeit der ESR-spektroskopische Nachweis von strahlenbehandelten Trockenfrüchten besprochen wurde, wird in diesem Bericht die flüssigchromatographische Bestimmung der Kohlenhydratfraktion dieser Früchte vorgestellt und ein Zusammenhang zwischen der Zuckerzusammensetzung und den ESR-Signalstrukturen nachgewiesen. Die bei der Bestrahlung von Trockenfrüchten beobachteten ESR-Spektren lassen sich in 3 Typen unterteilen. Die Zuordnung der Trockenfrüchte zu den einzelnen Typen anhand ihrer Kohlenhydratzusammensetzung gelingt in einer überwiegenden Zahl der untersuchten Proben. Weiterhin wird festgestellt, daß die beobachteten ESR-Signale in ihrem Habitus denen der reinen bestrahlten Mono- und Disaccharide ähnlich sind. Dies trifft besonders für saccharosereiche Früchte und Saccharose zu. Die Struktur der ESR-Spektren strahlenbehandelter Trockenfrüchte kann sich über einen längeren Zeitraum ändern. Für die Veränderung werden radikalische Umwandlungen in der Probenmatrix verantwortlich gemacht.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01614431
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 63
    Electronic Resource
    Electronic Resource
    Orogenic evolution of the Hellenides: new aspects (1994)
    Springer
    International journal of earth sciences 83 (1994), S. 249-256 
    Details
    ISSN: 1437-3262
    Keywords: Mediterranean microplates ; Pre-Alpidic rifting ; Inversion ; Low angle faulting ; Intracrustal shearing
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract This progress report is based on investigations of the tectonometamorphic development of crystalline complexes and is restricted to a few key problems of the Hellenides: 1. ‘Hinterland’. Rhodopia is strongly affected by Alpidic metamorphism, granitoid intrusions, orogenic deformation and intracrustal delamination. Therefore, close relations between the Balkanides and Hellenides have to be considered. 2. External zones. The Phyllite-Quartzite Series probably originated in a Late Palaeozoic rift within Apulia. In Middle Triassic times rifting stopped and the area became the basement on an extended carbonate platform (Late Triassic-Liassic). From the Dogger to Palaeocene, parts of that platform subsided, forming the Ionian pelagic basin. The Eocene orogenesis within the central Hellenides then caused an inversion of the buried Phyllite-Quartzite rift zone, whereas from the Late Oligocene onwards the previous rift zone underwent continental (A-) subduction. Finally, uplift of the Phyllite-Quartzite Series and nappe emplacement started in Miocene times. 3. Late orogenic intracrustal shearing. Structural analyses of crystalline complexes of Attica have shown that neotectonic extension and the large vertical displacement of the Aegean region were caused by low angle faulting and large-scale shearing within the deeper crust, probably along former overthrust planes. These results reveal the mechanisms of intracratonic tectonics, remobilization of continental crust and intracrustal detachment throughout the evolution of the Hellenides.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00210543
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 64
    Electronic Resource
    Electronic Resource
    Radicals on surfaces formed by ionizing radiation (1994)
    Springer
    Molecular engineering 4 (1994), S. 179-199 
    Details
    ISSN: 1572-8951
    Keywords: ESR ; radical ; radical ions ; ionizing radiation ; paramagnetic metal ions ; metal clusters ; metal metal oxides ; zeolites ; alkane ; alkenes ; alkynes ; benzene ; fluorinated benzenes ; sodium clusters ; silver clusters ; silica clathrates
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract An overview is presented of radicals generated on porous metal oxide surfaces such as zeolites whose main source of generation has been ionizing radiation. Attention is primarily paid to ESR studies on structures and reactions of organic neutral and ionic radicals. A short introduction is also given to paramagnetic metal ions and clusters formed in zeolites and other related materials.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01004054
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 65
    Electronic Resource
    Electronic Resource
    Study of catalytic site structure and diffusion of radicals in porous heterogenous systems with ESR, ENDOR and ESE (1994)
    Springer
    Molecular engineering 4 (1994), S. 39-59 
    Details
    ISSN: 1572-8951
    Keywords: ESR ; ENDOR ; ESE ; Lewis acid sites ; paramagnetic complexes ; zeolites ; diffusion processes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The generation of paramagnetic products by adsorption of quinones on activated catalysts has been used for the diagnostic of Lewis acid sites. It has been shown that the application of ENDOR, ESE, and 2 mm-band ESR are extremely effective methods for studying the nature of observed radical species and their environment. Two applications of the ESE method for studying the diffusion of spin probes in porous media are considered. The measurement of effective diffusion coefficients of radical probes in specimens of various heterogeneous systems is described. It has been found that effective diffusion coefficients depend strongly on the mean value of silica gel pore sizes and the mobility of the probe inside the pore.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01004049
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 66
    Electronic Resource
    Electronic Resource
    Radical steps in the reactions of organometallic compounds with 2-methyl-2-nitrosopropane: experimental evaluation of the validity of the nitroxyl method for investigations of homolytic reactions of organometallic compounds (1994)
    Springer
    Russian chemical bulletin 43 (1994), S. 862-866 
    Details
    ISSN: 1573-9171
    Keywords: radicals ; spin traps ; organometallic compounds ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Radical adducts formed in the reactions of organometallic compounds of group II-V elements and of some organochromium and organoiron compounds with 2-methyl-2-nitrosopropane and phenyl(tert-butyl)nitrone were studied by ESR. Nitroso compounds and nitrones can be used as selective spin traps for investigations of homolytic reactions involving organometallic compounds.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00717356
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 67
    Electronic Resource
    Electronic Resource
    Conformational isomerisin of phosphorus-containing fullerenyl radicals (1994)
    Springer
    Russian chemical bulletin 43 (1994), S. 1582-1584 
    Details
    ISSN: 1573-9171
    Keywords: fullerene, phosphorus-containing fullerenyl radicals ; conformational isomerism ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract ESR spectra of phosphorus-containing fullerenyl radicals.C60-P(O)(OPr1)2 and. C60-P(O)(OEt)Ph were studied at low temperatures (193–273 K). A decrease in the rate of rotation of organophosphorus group around the C-P bond results first in line broadening and then in the appearance of two doublets due to two “extreme” conformations, which have differentg-factors and hyperfine coupling constants (HCC) of the unpaired electron with the31P nucleus. The kinetic and thermodynamic parameters of the conformational isomerism were calculated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00697155
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 68
    Electronic Resource
    Electronic Resource
    ESR spectroscopy of copper(ii) complexes with aza- and thia-containing crown ethers (1994)
    Springer
    Russian chemical bulletin 43 (1994), S. 1827-1833 
    Details
    ISSN: 1573-9171
    Keywords: crown ethers ; ESR ; complexes with copper(ii) ; electron absorption spectroscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Six copper(ii) chloride complexes with crown ethers containing besides oxygen also nitrogen or sulfur atoms in 15- or 18-membered cycle were studied by ESR and electron absorption spectroscopies. Theg and HFI tensor components determined by spectral simulation indicate rhombic symmetry and localization of an unpaired electron on the d xy orbital for all the complexes. The unpaired electron fractions on σ- and π-type metal ion and ligand AO were estimated from ESR and absorption spectra using LCAO MO method. Both σ- and π-type bond covalences were shown to be greater in these complexes compared to only oxygen-containing crown ether complexes. The temperature dependence of g and A components in some complexes may be due to conformational changes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00696310
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 69
    Electronic Resource
    Electronic Resource
    Model investigation of the polymerization of acrylamide complexes with metal nitrates by ESR (1994)
    Springer
    Russian chemical bulletin 43 (1994), S. 494-496 
    Details
    ISSN: 1573-9171
    Keywords: acrylamide ; calcium nitrate ; polymerization ; ESR ; nitroxyl radical
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Modelling experiments have shown that the interaction between NO2 and acrylamide (AA) and the AA complex with calcium nitrate leads to the formation of radical centers. Analogous paramagnetic centers are detected directly in AA complexes with calcium nitrate. The ESR spectrum differs from that of γ-irradiated AA and is caused by nitroxyl radicals appearing in the course of the consecutive transformations in the system. The data obtained support the earlier suggested mechanism of NO2-initiated polymerization of acrylamide complexes with metal nitrates.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01169734
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 70
    Electronic Resource
    Electronic Resource
    ESR study of radicals obtained from vinylalkoxysilanes and their adducts with branched fluoroalkenes (1994)
    Springer
    Russian chemical bulletin 43 (1994), S. 498-500 
    Details
    ISSN: 1573-9171
    Keywords: vinylalkoxysilanes ; fluoroalkene ; radical ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract ESR spectra of radicals obtained by abstracting a hydrogen atom from methylvinyldimethoxysilane and methylvinyldiethoxysilane through the action of thetert-butoxy radical were studied. It was shown that the radicals appearing react with branched fluorinated olefins to give relatively stable radical adducts.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01169736
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 71
    Electronic Resource
    Electronic Resource
    ESR study of the effect of water on the kinetics of proton transfer and exchange in solutions of semiquinone radicals (1994)
    Springer
    Russian chemical bulletin 43 (1994), S. 953-956 
    Details
    ISSN: 1573-9171
    Keywords: 3,6-di-tert-butyl-2-hydroxyphenoxyl ; triethylamine ; diethylamine ; complexing ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The interaction of 3,6-di-tert-butyl-2-hydroxyphenoxyl with triethylamine in the reaction of proton transfer is catalyzed by water. However, the rate of proton exchange with diethylamine is independent of water admixtures in the reaction medium. ESR showed that the complexing of 3,6-di-tert-butyl-2-hydroxyphenoxyl with water leads to redistribution of the spin density.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01558055
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 72
    Electronic Resource
    Electronic Resource
    Physicochemical properties of a muramyldipeptide derivative (B30-MDP) related to membrane formation (1994)
    Springer
    Colloid & polymer science 272 (1994), S. 1281-1288 
    Details
    ISSN: 1435-1536
    Keywords: B30-MDP ; dipalmitoylphosphatidylcholine ; DSC ; ESR ; liposome
    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 investigated the physicochemical properties of B30-MDP [6-O-(2-tetradecylhexadecanoyl)-N-acetyl-muramyl-L-alanyl-D-isoglutamine], a muramyldipeptide derivative having immunoadjuvant activity [1], using polarizing optical microscopy, differential scanning calorimetry (DSC), and electron spin resonance (ESR) spectroscopy. Microscopic observations showed that B30-MDP molecules form myelin figures in phosphate buffered saline (PBS). It was revealed that B30-MDP forms membranous structure because of an increase in the hydrophobicity. In the DSC measurements, the B30-MDP membrane in PBS gave no endothermic peak between 5° to 50°C. Enthalpy change upon the phase transition from the gel to liquid crystalline state or dipalmitoylphosphatidylcholine (DPPC) membrane and its phase transition temperature decreased by the addition of B30-MDP. ESR measurements using 5 doxyl stearic acid showed that the fluidity of the B30-MDP membrane was almost comparable to that of DPPC membrane at the temperature below the phase transition temperature of DPPC, while it was lower than that of DPPC at the temperature higher than this point. The fluidity of DPPC membrane increased upon the addition of B30-MDP. These results indicate that B30-MDP forms membranous structure and that the bulky hydrophilic region of B30-MDP influences its membrane structures, thermal behavior, and membrane fluidity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00657782
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 73
    Electronic Resource
    Electronic Resource
    Effects of high electrolyte concentration on DPPC-multilayers: an ESR and DSC investigation (1994)
    Springer
    Colloid & polymer science 272 (1994), S. 1289-1294 
    Details
    ISSN: 1435-1536
    Keywords: Ionic strength ; DPPC ; multilayer ; ESR ; DSC
    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 effects of salinity on the lateral headgroup interactions of dipalmitoylphosphatidylcholine (DPPC) molecules in fully hydrated multilayers have been investigated by spin label electron spin resonance (ESR) spectroscopy and differential scanning calorimetry (DSC). By increasing the NaCl concentration from 0 to 3 M in the multilayers' dispersion medium, the ESR measurements performed with the 5-stearic acid spin label and di-tert-butyl-nitroxide show an increase in the orientational degree of order of the lipid molecules, mainly in the gel phase, and a decrease of the membrane permeability. An upward shift from 31.5° to 36.5°C and from 40.5° to 41.9°C of the pre- and main DPPC phase transition temperatures, respectively, is observed with 5-SASL, while slightly higher values are detected with DTBN. Small effects are evident on the properties of the liquid crystalline phase of the DPPC multilayers. The DSC measurements also reveal an upward shift of the pre- and main transition temperatures. The shifts, however, are more marked if compared to the ones observed with the ESR technique. The findings suggest an increase in the packing density of the DPPC molecules in the multilayers in presence of high salt concentration. Dehydration of the DPPC interfacial region with a variation of the lateral electrostatic interactions between phospholipid polar heads trigger the phenomena observed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00657783
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 74
    Electronic Resource
    Electronic Resource
    The radii inversion problem associated with the Hg capillary pressure experiment (1994)
    Springer
    Transport in porous media 14 (1994), S. 33-72 
    Details
    ISSN: 1573-1634
    Keywords: Inversion ; radii frequency ranges ; geometrically modelled pore space ; continuous radii distribution ; structural hysteresis ; contact angle hysteresis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Technology
    Notes: Abstract Today's practice of interpreting Hg capillary pressure curves — a widespread method in porosimetry — is generally unsatisfactory. This has already been demonstrated by Fatt. First, the saturation branch of such a curve is interpreted using the concept of a pore space model in which essential features of a network structure are disregarded. Second, the data provided by the desaturation branch are not used. Distributions of radii of capillaries within porous materials derived by this technique are usually incorrect in that the frequencies of occurrence of the greater radii turn out too small, those of the smaller radii too large. We present a more reliable approach which constrains radii frequency ranges for the Hg saturated pore space and for both the part of the pore space that desaturates and the part that traps mercury when Hg pressure is released. The pore space may be of an arbitrary geometrical structure, the radii distribution may be continuous. Also, the Hg desaturation may enable one to distinguish experimentally between structural and contact angle hysteresis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00617027
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 75
    Electronic Resource
    Electronic Resource
    ESR studies of organic radical cations in zeolites (1994)
    Springer
    Molecular engineering 4 (1994), S. 119-145 
    Details
    ISSN: 1572-8951
    Keywords: Zeolites ; radical cations ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract An overview is presented of the formation of organic radical cations in zeolites. Attention is paid firstly to their deliberate production by radiolysis and then to the spontaneous oxidation by activated H-exchanged zeolites of adsorped organic substrates. The nature of the oxidation site arising from thermal pretreatment in oxygen is considered, and possible mechanistic details are outlined for the frequently observed oligomerisations of simple substrates. The broad conclusions are that radical cations are formed from that component of the organic product mixture with the lowest ionisation potential, and that the dominant molecular transformations are driven by proton (Brønsted) catalysis: it appears that there is little evidence that radical cations are involved particularly in heterogeneous catalysis by zeolites, but they may well precede the formation of neutral radicals which are implicated as reaction intermediates. The reorientational dynamics of alkene radical cations in zeolites, as determined by ESR spectroscopy, are also considered.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01004052
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 76
    Electronic Resource
    Electronic Resource
    ESR and quantum chemical studies of the structures and thermal transformations of the radical cations of vinylcyclopropane in irradiated frozen Freon matrices. Simulation of radical processes in solids (1994)
    Springer
    Russian chemical bulletin 43 (1994), S. 1-12 
    Details
    ISSN: 1573-9171
    Keywords: radiolysis, Freon matrices ; vinylcyclopropane, primary radical cations, distonic radical cation, dimeric radical cation ; thermal rearrangement ; solid phase ; ESR ; quantum chemical analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Thermal transformations of vinylcyclopropane radical cations (VCP.+) in X-ray-irradiated frozen Freon matrices (CFCl2CF2Cl and CFCl3) were studied by ESR; radical processes involving VCP.+ in solid VCP were simulated.Gauche- andanti-VCP .+ were found to be the primary radical cations, however, the former, unlike the latter, is stable only under “gas-phase” conditions. The thermodynamic equilibrium betweenanti-VCP.+ and its less stable distonic form,dist(90,0)-C 5H8 .+, is established in frozen Freon matrices and the VCP host matrix; the structure of dist(90,0)****-C 5H8 .+ is stabilized by a molecule ofanti-VCP. In CFC3, along with dist(90,0)-C5H8 .+,π-dimeric resonance [anti-VCP]2 .+ complex was detected. A general scheme of the transformations of VCP.+ in the solid phase has been proposed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00699126
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 77
    Electronic Resource
    Electronic Resource
    ESR study of spin-adducts of trimethylaminoboryl radicals with fullerene C60 (1994)
    Springer
    Russian chemical bulletin 43 (1994), S. 624-626 
    Details
    ISSN: 1573-9171
    Keywords: fullerene ; ESR ; radical ; photolysis ; boryl
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract It was established by ESR that trimethylaminoboryl radicals formed by UV irradiation of BH3NMe6w in the presence of di-tert-butyl peroxide in saturated benzene solutions of fullerene C60, add to fullerenes to give C60-BH2NMe3 spin-adducts. The latter undergo dimerization with a rate constant ofca. 2.5 · 106 L mol−1 s−1. A more prolonged photolysis of excess BH3NMe3 in a benzene solution of C60 results in multiple addition of the trimethylaminoboryl radicals to the fullerene to give stable radicals C60[BH2NMe3]n.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00699836
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 78
    Electronic Resource
    Electronic Resource
    Interaction of fullerene C60 with 3-amino-1-propanol (1994)
    Springer
    Russian chemical bulletin 43 (1994), S. 1081-1083 
    Details
    ISSN: 1573-9171
    Keywords: fullerene ; radical anion ; 3-amino-1-propanol ; ESR ; IR ; X-ray photoelectronic spectroscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The C60 radical anions formed in the interaction of c60 with 3-amino-1-propanol under a vacuum were characterized by ESR and near-IR spectroscopy. in the air, a compound was obtained whose composition corresponds to the C60∶NH2CH2CH2CH2OH=1∶3.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01558086
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 79
    Electronic Resource
    Electronic Resource
    Reduced inverse for controlled systems (1993)
    Springer
    Mathematics of control, signals, and systems 6 (1993), S. 363-379 
    Details
    ISSN: 1435-568X
    Keywords: Nonlinear systems ; Inversion ; Left-inverse system ; Observability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology , Mathematics , Technology
    Notes: Abstract The left-invertibility and the general construction of reduced inverse systems are studied and described in a unified vector-space approach for both linear and nonlinear systems. The order of reduced inverse systems is calculated by means of intrinsic invariants, which reflect some properties related to observability. The uniqueness of the reduced inverse is described by a factor space.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01211502
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 80
    Electronic Resource
    Electronic Resource
    Study of surface properties of dodecatungstophosphoric acid by means of ionization of aromatic hydrocarbons (1993)
    Springer
    Catalysis letters 22 (1993), S. 387-392 
    Details
    ISSN: 1572-879X
    Keywords: Hydrocarbon ionization ; ESR ; dodecatungstophosphoric acid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The surface properties of H3PW12O40 are initially dependent on pretreatment temperature as can be deduced from the ionization of adsorbed aromatic hydrocarbons. Not only does surface dehydration proceed at a lower temperature than bulk dehydration but also highly reactive species (ionized benzene) are generated by the loss of protons of polyanions in special locations such as corner or edge positions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00807248
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 81
    Electronic Resource
    Electronic Resource
    Interaction between ammonium sulfate-iron oxide shown by ESR and Mössbauer spectroscopy (1993)
    Springer
    Catalysis letters 18 (1993), S. 317-322 
    Details
    ISSN: 1572-879X
    Keywords: Ammonium sulfate ; iron oxide ; solid acid ; ESR ; Mössbauer spectroscopy ; IR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The ammonium sulfate-iron oxide system treated at different temperatures has been characterized by ESR, IR and Mössbauer spectroscopy. Results show that during the heat treatment some interaction between ammonium sulfate and iron oxide takes place. As a result of this interaction a surface sulfato complex of iron is formed. The complex is involved in the sites responsible for activity for acid catalytic esterification. Above 573 K, the sulfato complex will gradually decompose with a further increase in temperature. A new structure scheme of the sulfato complex is proposed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00769452
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 82
    Electronic Resource
    Electronic Resource
    Equilibria of polyoxometalates in aqueous solution (1993)
    Springer
    Molecular engineering 3 (1993), S. 29-42 
    Details
    ISSN: 1572-8951
    Keywords: Polyoxometalate ; equilibria ; potentiometry ; NMR(31P,51V) ; redox ; ESR ; molybdate ; vanadate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract In most aqueous polyoxometalate systems, numerous, often highly negatively charged species, are formed. To establish the speciation in such complex polyanion systems, many experimental methods and techniques must be used. Moreover, it is of vital importance that the experimental data are of the highest accuracy and that the data collected from different methods are treated simultaneously with an appropriate computer program. In systems containing one or more sensitive NMR nuclei, a combined EMF-NMR method has been shown to be extremely powerful. This article firstly gives some general comments on equilibria in aqueous polyoxometalate systems including ionic medium effects, and then describes an equilibrium EMF-NMR (31P and51V) study of the five component system H+-Mo(VI)-V(V)-P(V)-e−. The study has been focused on so-called Keggin ratio solutions, Mo+V):P=12:1, since these are commonly used in selective oxidation processes. Special attention has been given to Mo10V2P and Mo9V3P solutions, where positional isomers occur. We have been able to identify and characterize all the five possible isomers of α-Mo10V2PO 40 5− at 25 and 90 °C. Besides the results from the five component system, some interesting findings from the binary, ternary and quarternary sybsystems are also reported.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00999622
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 83
    Electronic Resource
    Electronic Resource
    Structure and evolution of the genomes ofsorghum bicolor andZea mays (1993)
    Springer
    Theoretical and applied genetics 86 (1993), S. 598-604 
    Details
    ISSN: 1432-2242
    Keywords: Maize-Sorghum-Restriction fragment length polymorphism ; Genetic maps ; Inversion ; Translocation ; Duplication
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Cloned maize genes and random maize genomic fragments were used to construct a genetic map of sorghum and to compare the structure of the maize and sorghum genomes. Most (266/280) of the maize DNA fragments hybridized to sorghum DNA and 145 of them detected polymorphisms. The segregation of 111 markers was analyzed in 55 F2 progeny. A genetic map was generated with 96 loci arranged in 15 linkage groups spanning 709 map units. Comparative genetic mapping of sorghum and maize is complicated by the fact that many loci are duplicated, often making the identification of orthologous sequences ambiguous. Relative map positions of probes which detect only a single locus in both species indicated that multiple rearrangements have occurred since their divergence, but that many chromosomal segments have conserved synteny. Some sorghum linkage groups were found to be composed of sequences that detect loci on two different maize chromosomes. The two maize chromosomes to which these loci mapped were generally those which commonly share duplicated sequences. Evolutionary models and implications are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00838715
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 84
    Electronic Resource
    Electronic Resource
    The electrochemical behavior ofortho-nitroanilides in an aprotic medium (1993)
    Springer
    Russian chemical bulletin 42 (1993), S. 1020-1023 
    Details
    ISSN: 1573-9171
    Keywords: polarography ; ESR ; ortho-nitroanilides ; electrochemical reduction ; anionradicals ; nitroso compounds
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Electrochemical reduction ofortho-nitroanilides in an aprotic medium has been studied by polarography and ESR. It has been shown that nitroanilide anion-radicals are formed at the first reduction wave potentials. The transfer of a second electron is accompanied by subsequent reactions (autoprotonation and homogeneous electron transfer), which occur in the bulk of the solution and lead to fairly stable intermediate anion-radicals ofortho-compounds.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00704190
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 85
    Electronic Resource
    Electronic Resource
    ESR study of carborane containing organofluorine radicals (1993)
    Springer
    Russian chemical bulletin 42 (1993), S. 1259-1261 
    Details
    ISSN: 1573-9171
    Keywords: ESR ; carboranyl radical ; fluorine compounds ; photochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract It has been shown by ESR that the addition of photochemically generated boroncentered carboranyl radicals to branched fluoroalkenes affords stable spin-adducts. It has been found that the addition of boron-centered radicals with 1-substituted 2-fluoroalkenyl-o-carborane gives stable α-carboranyl radicals. Negligible variations in the values of the constants of hyperfine coupling of the unpaired electron with the nucleus of the β-11B atom in radicals of various structures imply the stability of the carborane conformation with respect to the 2p z-orbital of the unpaired electron. This may be caused by hyperconjugation between the boron atom and the unpaired electron as well as steric interaction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00702021
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 86
    Electronic Resource
    Electronic Resource
    Allylic radicals as intermediates of free-radical phosphorylation of fullerene-70 (1993)
    Springer
    Russian chemical bulletin 42 (1993), S. 203-205 
    Details
    ISSN: 1573-9171
    Keywords: fullerene ; ESR ; radical ; phosphorylation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Multiple addition of photochemically generated · P(O)(OMe)2 radicals to C70 results in the formation of allylic radicals with three and five phosphoryl groups.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00700012
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 87
    Electronic Resource
    Electronic Resource
    Synthesis of the perfluoroacetyldiisopropylmethyl radical (1993)
    Springer
    Russian chemical bulletin 42 (1993), S. 207-208 
    Details
    ISSN: 1573-9171
    Keywords: radical ; perfluoroketone ; synthesis ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract A stable trifluoroacetylperfluorodiisopropylmethyl radical has been prepared by interaction of the (α-fluorosulfonyloxytetrafluoroethyl)perfluorodiisopropylmethyl radical with anhydrous CsF. This reaction is the first example of a chemical transformation of a C-centered radical which is not resonance-stabilized with retention of the radical center.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00700014
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 88
    Electronic Resource
    Electronic Resource
    Use of ESR for characterizing exchange-coupled polynuclear μ-oxo complexes of iron(iii) (1993)
    Springer
    Russian chemical bulletin 42 (1993), S. 421-423 
    Details
    ISSN: 1573-9171
    Keywords: polynuclear Fe(III) μ-oxo complexes ; antiferromagnetic interaction ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract ESR spectra of 13 bi-, tri- and tetranuclear μ-oxo complexes of Fe(III) were studied in the solid state and in solution. On the basis of the data obtained, the broad signal observed nearg=2 for all the complexes was interpreted as resulting from thermal populating of paramagnetic excited states.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00698420
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 89
    Electronic Resource
    Electronic Resource
    Spectral study of complexation ofcis,cis-1,3,5-tri[2-(diphenylphosphinyl)ethylamino]cyclohexane with copper(ii) and cobalt(ii) ions (1993)
    Springer
    Russian chemical bulletin 42 (1993), S. 1140-1144 
    Details
    ISSN: 1573-9171
    Keywords: complexation ; cyclopendant ligands ; phosphinyl groups ; structure of complexes ; UV-Vis ; ESR ; IR spectra
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The complexation ofcis,cis-1,3,5-tri[2-(diphenylphosphinyl)ethylamino]cyclohexane (L1) with Cu2+ and Co2+ cations has been studied in different solvents by means of UV-Vis, ESR, and IR spectroscopy. It has been shown that in the CuL1 complex the metal ion is pentacoordinated by three nitrogen atoms and two phosphinyl groups of the ligand and has a tetragonal-pyramidal environment. The conformation of the coordination polyhedron for the CuL1 complex depends on the solvent. In the CoL1 complex, as well as in the CoL2 complex, where L2 is 1,4,7-tris(2-diphenylphosphinylethyl)-1,4,7-triazacyclononane, the Co2+ ion has an octahedral environment and is bound to all donor atoms of the ligands.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00701991
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 90
    Electronic Resource
    Electronic Resource
    ESR investigation on the phase transitions of DPPC vesicles in presence of high concentrations of Li+, Na+, K+ and Cs+ (1993)
    Springer
    Colloid & polymer science 271 (1993), S. 262-267 
    Details
    ISSN: 1435-1536
    Keywords: DPPC ; ESR ; spin label ; ionic strength ; monovalent cations
    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 partition of the spin label TEMPO in the hydrophobic region of di-palmitoyl-phosphatidylcholine unilamellar vesicles has been used to investigate the influence of high concentration (up 3M) of Li+, Na+, K+, and Cs+ on the phase transitions at 20–60°C. All of the above salts increase the permeation of TEMPO. The efficiency of monovalent cations in inducing the partition of the spin label in the hydrophobic environment of the bilayer increases in the order: Cs+〈Li+〈Na+〈K+. The disappearing of the pretransition and the downward shift of the main phase transition temperature from ≊37°C to ≊33.5°C is related to the increased permeation of TEMPO into the bilayer. The presence of salts in the bulk solution disturbs the hydration of the zwitterionic polar head of the DPPC molecules and changes the electrical interaction between the polar groups of the bilayer. This reduces the packing density of the lipid molecules and promotes the permeation of TEMPO.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00652366
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 91
    facet.materialart.
    Unknown
    The Rytov approximation aids the resolution of the broad velocity components in non-linear waveform inversion (1993)
    European Association of Exploration Geophysicists
    In:  pres. at 55th EAEG Meeting, Stavanger, European Association of Exploration Geophysicists, vol. 339-350, no. 32, pp. 103-108, (ISBN 3-933346-037)
    Details
    Publication Date: 1993
    Keywords: Scattering ; Inversion ; Generalized Radon Transformation ; Seismics (controlled source seismology)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    BIBLIOGRAPHY SEISMOLOGY
  • 92
    facet.materialart.
    Unknown
    Walkaway Vertical seismic profiling or Fixed Offset Vertical seismic profiling? A case history in the Lille Frigg Field (1993)
    European Association of Exploration Geophysicists
    In:  paper pres. at 55th EAEG Meeting, Stavanger, European Association of Exploration Geophysicists, vol. C 560, 183 pp., no. 22, pp. 1143-1146 (SL3.8), (ISBN 3-933346-037)
    Details
    Publication Date: 1993
    Keywords: Scattering ; Inversion ; Generalized Radon Transformation ; Vertical seismic profiling ; Moving source Vertical seismic profiling ; Seismics (controlled source seismology)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    BIBLIOGRAPHY SEISMOLOGY
  • 93
    Electronic Resource
    Electronic Resource
    Stand der Entwicklung der Elektronen-Spin-Resonanz-Messung zum Nachweis bestrahlter Lebensmittel (1992)
    Springer
    European journal of nutrition 31 (1992), S. 205-218 
    Details
    ISSN: 1436-6215
    Keywords: ESR ; Lebensmittelbestrahlung ; Knochen ; Früchte ; Nüsse ; Gewürze ; ESR ; food irradiation ; bones ; fruits ; nuts ; spices
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Medicine
    Description / Table of Contents: Summary Electron spin resonance spectroscopy can be used for the detection of irradiation of various groups of foodstuffs. The results of ESR-measurements on irradiated meat and fish and fresh fruit, as well as dried fruit, spices and nuts as performed by the food irradiation laboratory of the German Federal Health Office are summarized in this report. For the detection of irradiated meat and fish, we examined the bones. Using the results from 10 different animal bones, we were able to develop an official method according to the German law § 35 LMBG. A similar routine method for fish will be established in 1992 (at the moment, an intercomparison with German food control laboratories is in progress). Irradiated dried fruit can be identified easily, because unirradiated samples give no ESR-spectra, while irradiated fruit show a partially resolved spectrum, which is caused by radiation induced sugar radicals. Interestingly, the structure of the resulting spectra is not identical for all irradiated species of fruit. We found three different types of ESR-spectra for irradiated dried fruit. Irradiated nutshells show an ESR-spectrum which reveals two additional lines (from cellulose-radicals) beside the main signal, while unirradiated samples show only the main signal. An official method for identifying irradiated nuts will be proposed in 1992. Irradiation specific ESR-signals of the cellulose radical were not only found for nutshells but also for fresh fruit and some spices, while most of the irradiated spices and herbs could not be identified by ESR-measurements.
    Notes: Zusammenfassung Die Elektronen-Spin-Resonanz-Spektroskopie kann zum Nachweis der Bestrahlung diverser Lebensmittelgruppen eingesetzt werden. In diesem Bericht werden die Ergebnisse des Bundesgesundheitsamtes bei der Entwicklung von ESR-Meßverfahren zur Identifizierung von strahlenbehandeltem Fleisch, Fisch und Frischobst sowie bestrahlten Trockenfrüchten, Gewürzen und Nüssen zusammengestellt. Bei Fleisch und Fisch sind die ESR-Spektren der enthaltenen Knochen untersucht worden. Die Ergebnisse von zehn verschiedenen Tierarten haben zur Entwicklung einer amtlichen Routinemethode nach § 35 LMBG für knochenhaltiges Fleisch geführt. Nach Durchführung eines zur Zeit laufenden Ringversuches unter Beteiligung der Lebensmittelkontrollämter wird eine solche Methode auch für Fisch erstellt werden können. Bestrahlte Trockenfrüchte können in der Regel leicht erkannt werden, da unbestrahlte Proben keinerlei ESR-Spektrum geben, während bestrahlte Proben ein partiell aufgelöstes Spektrum zeigen, das durch Zuckerradikale hervorgerufen wird. Interessanterweise ist die Struktur der Spektren unterschiedlich. Bei den untersuchten Fruchtarten wurden drei verschiedene Spektrentypen gefunden. Bei Nußschalen ist der eindeutige Nachweis einer γ-Bestrahlung durch das Auftreten zweier zusätzlicher Linien im ESR-Spektrum gegeben. Auch für diese Lebensmittelgruppe wird nach Abschluß eines z.Z. laufenden Ringversuches eine Routinemethode formuliert werden. Die wahrscheinlich durch die Bildung von Cellulose-Radikalen hervorgerufenen Signale in den ESR-Spektren bestrahlter Nußschalen können bei geeigneter Einstellung des Meßgerätes auch bei frischem Obst und einigen Gewürzen beobachtet und zum Nachweis herangezogen werden. Die Mehrzahl der untersuchten bestrahlten Gewürze und Kräuter zeigte diese Linien jedoch nicht, so daß in diesen Fällen mit Hilfe der ESR kein Nachweis der Bestrahlung erfolgen konnte.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01611143
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 94
    Electronic Resource
    Electronic Resource
    Study of the V2O5-Al2O3 interaction during ultra-high intensity grinding (1992)
    Springer
    Catalysis letters 13 (1992), S. 261-266 
    Details
    ISSN: 1572-879X
    Keywords: Vanadia ; alumina ; grinding ; ESR ; NMR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Ultrahigh intensity grinding of mechanical mixtures of V2O5 with γ-Al2O3 at ambient temperature was found to create vanadyl complexes with ESR spectral parameters identical to those of vanadia-alumina samples prepared by impregnation methods. No interaction was found after intensive grinding of γ-Al2O3 with V2O4.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00770998
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 95
    Electronic Resource
    Electronic Resource
    The retention of copper ions by AlPO4-5/VAPO-5 and their effect on reactant access (1992)
    Springer
    Catalysis letters 16 (1992), S. 1-9 
    Details
    ISSN: 1572-879X
    Keywords: Ion exchange ; AlPO4-5 ; VAPO-5 ; defect sites ; copper ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The reaction of copper salts with AlPO4-5 or Vv-VAPO-5 under acidic (CuCl2, pH adjusted to 2) but especially basic conditions (Cu(NH3) 4 2+ , pH adjusted to 9) gives ion incorporations greater than expected by a simple ion exchange mechanism (both AlPO4-5 and Vv-VAPO-5 could be expected to have no cation exchange capacity). Ion incorporation is proposed to occur initially at defect sites, and examination of the ESR spectrum of a dehydrated, evacuated CuCl2-exchanged AlPO4-5 shows that these defect sites give rise to a number of unique environments upon CuII incorporation. The CuCl2-exchanged VAPO-5 retains a significant toluene accessibility to the Vv sites in the VAPO-5. However, the toluene accessibility in the Cu(NH3) 4 2+ -exchanged VAPO-5 is significantly reduced and we propose this is due to a combination of the presence of crystalline CuO and structural collapse from reaction with base (NH4OH). The ability of treatment with base (NH4OH, pH ≈ 13) to restrict access of toluene to the Vv sites of the original VAPO-5 was verified in a separate experiment.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00764348
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 96
    Electronic Resource
    Electronic Resource
    Structure and reactivity of MoO3-MgO catalysts (1992)
    Springer
    Catalysis letters 12 (1992), S. 255-266 
    Details
    ISSN: 1572-879X
    Keywords: Metathesis ; hydrogenation ; molybdenum oxide ; magnesium oxide ; EXAFS ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Surface of OH groups on reduced MoO2-MgO catalysts such as $$ - - Mg - - O - - \begin{array}{*{20}c} {||} \\ {Mo} \\ | \\ \end{array} - - OH$$ may act as an active site for hydrogenation of propene. The surface hexa-coordinated Mo5+ ion (MO 6c 5+ ) was reduced to a lower number of cation such as Mo4+ or Mo3+ which act as an active site for metathesis of propene.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00767208
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 97
    Electronic Resource
    Electronic Resource
    Generation of superoxide anions byChattonella antiqua: Possible causes for fish death caused by ‘Red Tide’ (1992)
    Springer
    Cellular and molecular life sciences 48 (1992), S. 888-890 
    Details
    ISSN: 1420-9071
    Keywords: Red Tide ; Chattonella antiqua ; superoxide anions ; free radical ; ESR ; microvoltammetry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The generation of reactive free radicals byChattonella antiqua (‘Red Tide’), which may be a causative factor in fish death, has been demonstrated by electron spin resonance spectroscopy and a microelectrode technique. Electrochemical detection indicates that superoxide anions are produced as a primary product, and undergo further reactions during diffusion in glycocalyx to produce hydrogen, hydroxy-, and carbon-centered radicals which are detected by ESR as secondary products. It is proposed that these reactive radicals are responsible for the destruction of the mucous membranes of fish on exposure to ‘Red Tide’.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02118427
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 98
    Electronic Resource
    Electronic Resource
    On the aesthetics of inversion and osculation (1992)
    Springer
    The visual computer 8 (1992), S. 233-240 
    Details
    ISSN: 1432-2315
    Keywords: Computer art ; Inversion ; Osculation transformation circle packing
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Notes: Abstract The goal of this article is to present an informal introduction and tutorial on certain graphical aspects of inversion and osculation for the non-mathematician and to present artistic renditions using these methods.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01900658
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 99
    Electronic Resource
    Electronic Resource
    ESR study of the free radicals formed in the photolysis of α-ketofluorosulfates (1992)
    Springer
    Russian chemical bulletin 41 (1992), S. 594-596 
    Details
    ISSN: 1573-9171
    Keywords: ESR ; photolysis ; radical ; ketofluorosulfate ; delocalization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract ESR spectroscopy was used to establish that the UV irradiation of α-ketofluorosulfates containing an OSO 2 F group at a tertiary carbon atom gives radicals formed upon cleavage of the C-OSO 2 F bond. If the OSO 2 F group is attached to a primary or secondary carbon atom, we observe ordinary photodecomposition with cleavage of the acyl—carbon bond. The ESR spectra of the new radicals were studied. Replacement of fluorine by the OSO 2 F group in the trifluoromethyl radical leads to compression of the radical site. Branched α-oxoperfluoroalkyl radicals are not heteroallylic and the unpaired electron is localized largely on the carbon atom. The [(CF 3 ) 2 CF] 2 ĊC(O)CF 3 radical is stable in the air.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00863096
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 100
    Electronic Resource
    Electronic Resource
    ESR analysis of the kinetic alkalinity of pseudophedrine (1992)
    Springer
    Russian chemical bulletin 41 (1992), S. 1559-1562 
    Details
    ISSN: 1573-9171
    Keywords: ESR ; pseudoephedrine ; 3,6-di-tert-butyl-2-hydroxyphenoxyl ; ion pairs
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The kinetics of protonation of pseudoephedrine by 3,6-di-tert-butyl-2-hydroxyphenoxyl have been analyzed by the ESR technique. It was shown that protolysis of the radical produced closed ionic pairs with the pseudoephedrine cation in a dimer state.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00863572
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...