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
  • 1
    Electronic Resource
    Electronic Resource
    Immunocytochemical studies of the gonadotropic cells in the pituitary gland of male mullet, Mugil cephalus, during the annual reproductive cycle in both natural habitat and captivity (2000)
    Oxford, UK : Blackwell Science, Ltd
    Journal of applied ichthyology 16 (2000), S. 0 
    Details
    ISSN: 1439-0426
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Using antiserum specific for the β subunit of coho salmon gonadotropic hormone II (GTH II), an immunocytochemical study of Mugil cephalus (L.) pituitaries was conducted during the annual reproductive cycle of the male in both natural habitat and captivity. The gonadotropic potency of the pituitary gland in general underwent an obvious increase during testicular development, reaching a peak at the time of reproductive maturity. During the testicular cycle of M. cephalus, the GTH cells showed an increase in immunoreactive staining intensity, granulation, hypertrophy and hyperplasia during sexual maturation. However, degranulation, vacuolization, and weakened immunoreactivity of these cells occurred during spawning. The GTH cells in the pituitary gland of M. cephalus males reared in captivity appeared with high synthetic and secretory activity but the reproductive activity declined, as reflected in the form of low values of the gonadosomatic index (GSI) and earlier resorption of the testes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1439-0426.2000.00226.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Characteristics of tungsten substrate with Al"2O"3 coatings under UHV conditions
    Amsterdam : Elsevier
    Vacuum 38 (1988), S. 835-838 
    Details
    ISSN: 0042-207X
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0042-207X(88)90474-5
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Kinetics of Solid State Reactions Co2+, Cu2+ and Zn2+ Basic Carbonates with Some Aliphatic Acids (2000)
    Springer
    Journal of thermal analysis and calorimetry 63 (2000), S. 609-618 
    Details
    ISSN: 1572-8943
    Keywords: composition effect ; kinetic of solid ; organic acid diffusion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The kinetic description and mechanism of the solid-state reactions between metal basic carbonate (M=Co2+, Cu2+ and Zn2+) and aliphatic carboxylic acids (oxalic, tartaric, succinic and citric acids) were studied using non-isothermal analysis (TG, DTA) and capillary techniques. The reactions were found to proceed in all cases (except citric acid) by one mole of metal carbonate and two moles of metal carbonate and two moles of organic acid. The kinetic analyses of non-isothermal data were best described by each of the dimensional phase boundary R2 and two-dimensional diffusion controlled reactions D2. While the capillary technique showed that the initial reaction occurs at the phase boundary of the reactants and kinetically of the reacting controlled by diffusion mechanism in which the diffusion species through the product layers are the organic acids.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1010174828300
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Electrical conduction in γ-irradiated and unirradiated zinc-iron ferrites (1988)
    Springer
    Journal of materials science 23 (1988), S. 3083-3087 
    Details
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The electrical conductivity of γ-irradiated and unirradiated finely-divided spinels of composition (Zn x 2+ Fe 1−x 2+ Fe 2 3+ )O 4 2− was studied in a nitrogen atmosphere as a function of temperature. The results of both γ-irradiated and unirradiated ferrites with compositions x ⩽ 0.79 showed that the electrical conduction occurred by fast electron exchange amongst Fe2+ and Fe3+ ions situated on octahedral sites in the spinel lattice, by a hopping mechanism. For composition x 〉 0.79 it was found that the transition of the charge carriers through cation vacancies is the predominant mechanism. Some breaks in the conductivity-temperature curves were found near the Curie points. Seebeck voltage measurements showed that γ-irradiated and unirradiated spinels behave as n-type semiconductors. The effect of γ-irradiation on the conductivity, activation energy, charge carriers and the conduction mechanism is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00551277
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Electrical conduction in γ-irradiated and unirradiated Fe3O4, CdFe2O4 and Co x ZN1−x Fe2O4 (0 ⩽x ⩽ 1) ferrites (1989)
    Springer
    Journal of materials science 24 (1989), S. 2478-2482 
    Details
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The electrical conductivity of γ-irradiated and unirradiated finely divided ferrites of composition Fe3O4, CdFe2O4 and Co x Fn1−x Fe2O4(0 ≤x ≤ 1) was studied in a nitrogen atmosphere as a function of temperature. Fe3O4, ZnFe2O4 and CdFe2O4 showed n-type conduction, whereas CoFe2O4 showed p-type conduction. For Co x Zn1-x Fe2O4 it was found that the type of conduction varies with the composition of ferrites. The electrical conduction in Fe3O4, and Co x Zn1−x Fe2O4(0 ⩽x ≤ 1) was explained by a hopping mechanism, whereas the conduction in ZnFe2O4 and in CdFe2O4 is interpreted on the basis of the transfer of charge carriers through cation vacancies present on octahedral sites. The effect of γ-irradiation on the conductivity, activation energy, charge carriers and the conduction mechanism is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01174515
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Electrical conduction in some gamma irradiated and unirradiated two-dimensional compounds, (CH2)8(NH3)2Co1−x Zn x Cl4 (1992)
    Springer
    Journal of materials science 3 (1992), S. 1-4 
    Details
    ISSN: 1573-482X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The electrical conductivity of γ-irradiated and unirradiated complexes of (CH2)8(NH3)2Co1−x Zn x Cl4 (x=0, 0.2, 0.4, 0.6, 0.8 and 1) was measured in the temperature range from 300 K to a temperature near the melting points of the samples. The results showed an increase in the conductivity values with increasing concentration of zinc ions in the samples. Both differential scanning calorimeter (DSC) and conductivity measurements showed the presence of many phase transitions in each of the complexes investigated. The results of irradiated compounds with a composition of 0≤x≤0.8 showed an increase in the conductivity values, at lower temperatures, compared with the values of unirradiated ones. For compositionx=1 no change in the conductivity data has been observed after irradiation. The effect of change in the chemical composition and irradiation on the conductivity data are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00701085
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Electrical conduction in some (CnH2n) (NH 3 + )2 FeCl4 compounds (1988)
    Springer
    Journal of materials science 23 (1988), S. 4345-4348 
    Details
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The d.c. conductivity, a.c. conductivity and thermoelectric power of the compounds H3N+(CH2)+ NH3FeCl4, wheren=2, 3, 7 and 10, have been studied over a temperature range of 150–500 K. The conductivity results confirm the presence of more than one structural phase transition for each compound investigated. The thermoelectric power measurements showed that electrons are the main charge carriers in all crystal phases. The conductivity results were explained on the basis of an electron hopping mechanism over the whole temperature range.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00551929
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Delayed self-organized criticality and earthquake modeling (1997)
    Springer
    International journal of theoretical physics 36 (1997), S. 3065-3069 
    Details
    ISSN: 1572-9575
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Delayed self-organized criticality is defined. It is shown to preserve the power-law behavior of self-organized criticality with a significant change in the exponents. A delayed version of the Ito—Matsuzaki model for earthquakes is constructed and studied. This model explains some fractal features of earthquakes as well as the Gutenberg-Richter and Omori laws. Furthermore theb value obtained from the delayed model is closer to observations than theb value of the undelayed model.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02435727
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Physicochemical studies on ZnO-Al2O3 system (1990)
    Springer
    Journal of materials science 25 (1990), S. 3067-3071 
    Details
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Several mixed ZnO-Al2O3 systems were prepared by the impregnation method and calcined for 5 h at 300, 600 and 1000 ° C. The crystal structure, surface acidity, surface basicity, surface area, catalytic decomposition of H2O2 and the electrical conductivity of the samples prepared were studied. It was found that the decomposition of H2O2 is catalysed by the acidic sites formed on the catalyst surface at composition less than 50 mol% ZnO and by basic sites for oxides having composition higher than 50 mol% ZnO. ZnAl2O4-spinel was found to be formed at temperatures ⩾ 600 ° C and it has a catalytic activity and electrical conductivity lower than each of the pure ZnO and the oxide mixtures. The results obtained were correlated together and discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00587651
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Temperature effect on magnetic and electrical properties of the compound Fe(DMSO)2Cl2 (1989)
    Springer
    Journal of materials science 8 (1989), S. 104-106 
    Details
    ISSN: 1573-4811
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00720266
    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...