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
    Production of ultrafine aluminum and aluminum nitride particles by plasma–alloy reaction and their microstructure and morphology (1992)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 71 (1992), S. 4025-4029 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The preparation condition, microstructure, and morphology of ultrafine Al and AlN particles were examined by a combined technique of nitrogen plasma–aluminum reaction and spray deposition as well as by metallographic techniques. The Al and AlN particles have the morphologies of sphere and hexagonal plate, respectively, and the particle size is 5 to 200 nm for Al and 20 to 120 nm for AlN. The volume ratio of AlN to Al increases continuously with an increase of the mixing gas ratio of nitrogen to argon and the total pressure of nitrogen and reaches about 25% in a nitrogen atmosphere with a pressure of 93 kPa. The composite Al–AlN particles are also observed and have an orientation relationship of (111)Al//(001)AlN, [101¯]Al//[110]AlN, and [12¯1]Al//[11¯0]AlN, in which the lattice misfit is as small as 6.4%, 8.6%, and 8.6%, respectively. The formation of the composite particles is presumed to result from the collision and incorporation of Al particles with the AlN plate adhered to Al particles. The Al and AlN particles produced by the present method are concluded to be small and homogeneous enough to be used as raw materials for the production of nanoscale composites and compositionally gradient materials.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.350825
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Production of compositionally gradient Al-AlN films by reactive sputtering and their mechanical and electrical properties (1992)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 71 (1992), S. 3278-3282 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The application of reactive sputtering in a mixed gas of argon (Ar) and nitrogen (N2) to Al metal resulted in the formation of compositionally gradient film consisting of Al and AlN phases. By changing the mixing gas ratio of N2 to N2+Ar so as to be 0, 0.05, 0.1, and 0.2 in a total gas pressure of 1 Pa, the resulting phase changes in the order of Al, Al+AlN, AlN+Al, and AlN and the thickness of each phase is 14, 23, 18, and 8 μm, respectively, after sputtering for 3.6, 5.4, 7.2, and 10.8 ks, respectively. The Al concentration along the sample thickness changes from 100% to about 50% with an increase of mixing ratio from 0 to 0.2. The lattice parameters of Al and AlN phases remain constant along the sample thickness. The Knoop hardness and the electrical resistivity increase steeply from 100 to 3900 and from 3×10−8 Ω m to an infinite value, respectively, with the phase transition from Al to AlN through Al+AlN and AlN+Al. The load leading to an exfoliation among the layers was measured to be 16 N. Thus, the sputtered Al-AlN film is concluded to possess functionally gradient characteristics resulting from the compositional and structural gradients.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.350975
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Magnetic properties of very high permeability, low coercivity, and high electrical resistivity in Fe87Zr7B5Ag1 amorphous alloy (1995)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 77 (1995), S. 5298-5302 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The magnetic properties of an Fe87Zr7B5Ag1 (at. %) amorphous alloy, which contains an additional insoluble element (Ag) in a small amount, have been investigated as a function of annealing temperatures in order to know its potential applicability as a core material used at high-frequency. As a result, a new excellent soft magnetic material with very high resistivity was developed. The amorphous alloy annealed at a relatively low temperature of Ta=300 °C exhibited a very high initial permeability μi of 146 000 at 1 kHz and 2 mOe, resistivity ρRT of 4.5 μΩ m, and very low coercivity Hc of 20 mOe, respectively. The values obtained are the best ones among various kinds of Fe-based soft amorphous materials reported up to now. Furthermore, the amorphous ribbon heat treated at Ta=300 °C still retained good ductility enough to endure 180° bending, which is very important from the viewpoint of processing for mass production. The phenomenon of good soft magnetic properties presumably arises from the homogenous formation of very fine α-Fe clusters in an amorphous matrix, which can be deduced from the increase of resistivity, and the reduction of magnetostriction caused by the dissolution of Zr and B into the α-Fe cluster. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.359284
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Multilayered structure and anisotropic electrical properties of (SiO2)100−x(Pb0.6Bi0.4)x alloys prepared by a combined technique of mechanical alloying and hot pressing (1990)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 57 (1990), S. 1052-1054 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Compacted (SiO2)100−x(Pb0.6Bi0.4)x (x=20–80 at. %) materials, prepared by mechanical alloying (MA) of amorphous SiO2, fcc Pb, and rhombohedral hexagonal Bi followed by hot pressing of the MA powder at 473 K for 1.8 ks under an applied stress of 250 MPa, were found to have a unique layered structure consisting of amorphous SiO2 and hexagonal close-packed (hcp) ε(Pb-Bi) phases which developed along the direction perpendicular to the uniaxial applied load. The thickness and interlayer distance of the layered ε (Pb-Bi) phase are about 1.5 and 7 μm, respectively, for (SiO2)50Pb30Bi20. Furthermore, the multilayered compacts exhibited a strong anisotropy of electrical resistivity and superconducting properties when their properties are measured along the directions parallel or perpendicular to the layer. Electrical resistivity at 300 K, superconducting critical temperature (Tc), and upper critical magnetic field (Hc2) at 4.2 K are 10.5 μΩ m, 8.5 K, and 2.29 T, respectively, for the parallel direction and 950 μΩ m, 6.9 K, and 0.24 T, respectively, for the perpendicular direction. The strong anisotropy of electrical resistivity and superconducting properties is presumably due to a significant difference in the linkage of electrical path between the parallel and perpendicular directions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.104279
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Nonlinear Bragg reflector based on saturable absorption (1989)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 54 (1989), S. 1095-1097 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The first observation of nonlinear reflection from a Bragg reflector composed of Ga0.8 Al0.2As/AlAs layers due to the band filling effect was measured by the pump probe method. The nonlinearity was primarily due to saturable absorption. Optically induced reflectivity changes of as much as 38% were measured.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.100768
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Optical bistability and nonlinear switching due to increasing absorption in single-crystal ZnSe waveguides (1987)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 51 (1987), S. 475-477 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Optical nonlinear switching and bistability due to increasing absorption have been observed in single-crystal ZnSe waveguides with contrast ratios of 16/1 and switching times of 10 μs at 15 mW of argon laser light. Switching energy is improved over the bulk by a factor of 200.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.98398
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Blue light generation by resonator-enhanced frequency doubling of an extended-cavity diode laser (1994)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 65 (1994), S. 525-527 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Frequency doubling of diode laser radiation was achieved by operating an AR-coated diode laser in an extended laser cavity which contained a monolithic potassium niobate frequency doubling resonator as an intracavity element. Extended cavity operation ensured that the diode laser would oscillate only at frequencies that were resonant with the intracavity resonator. A diffraction grating was used to ensure single mode oscillation at the wavelength needed for noncritically phase-matched second harmonic generation. At 100 mA of injection current to the GaAlAs diode laser, 14 mW of 429 nm light were produced.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.112286
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Enhanced Subtilisin Production with Spore Mutants of Bacillus subtilis and Their Characterization (1995)
    Oxford, UK : Blackwell Publishing Ltd
    Annals of the New York Academy of Sciences 750 (1995), S. 0 
    Details
    ISSN: 1749-6632
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Natural Sciences in General
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1749-6632.1995.tb19994.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Stimulating effects of pond water on digestive enzyme activity in the Pacific white shrimp, Litopenaeus vannamei (Boone) (2001)
    Oxford, UK : Blackwell Science Ltd
    Aquaculture research 32 (2001), S. 0 
    Details
    ISSN: 1365-2109
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Crude enzyme extracts were obtained from the digestive glands of Pacific white shrimp, Litopenaeus vannamei (Boone), reared in oligotrophic well water and eutrophic shrimp pond water to compare digestive enzyme activity between the two groups. Specific activities of serine protease, collagenase, amylase, cellulase, lipase and acid phosphatase were significantly higher (P 〈 0.01) in pond water-reared shrimp (PW shrimp) than in well water reared-shrimp (WW shrimp). For most enzymes assayed, specific activity was more than two times higher in PW shrimp, and cellulase activity was over six times higher. In contrast, chitinase activity was significantly higher (P 〈 0.001) in WW shrimp. Higher specific activity of most digestive enzymes in PW shrimp was probably due to natural productivity in the pond water that served as a source of organic substrates, and this increased activity may contribute to the growth-enhancing effect of shrimp pond water.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2109.2001.00540.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Digestive enzymes present in Pacific threadfin Polydactylus sexfilis (Bloch & Schneider 1801) and bluefin trevally Caranx melampygus (Cuvier 1833) (1999)
    Oxford, UK : Blackwell Science Ltd
    Aquaculture research 30 (1999), S. 0 
    Details
    ISSN: 1365-2109
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Pacific threadfin Polydactylus sexfilis (Bloch & Schneider 1801) and bluefin trevally Caranx melampygus (Cuvier 1833) are warmwater marine finfish currently under development for aquaculture in the Pacific. Differences in specific activities of digestive enzymes extracted from the stomach and mid-gut were compared to gain insight into their feeding habits in the wild and to understand their nutritional needs. Adult fish were maintained in captivity and fed a commercial pelleted feed. Serine protease measured in all tissues was at least 20 times higher in threadfin than in trevally. Aspartic proteases were the major digestive enzymes found in trevally. There was a 34-fold increase in collagenase activity in the intestine of threadfin from the prefed to the fed state. Chitinase activity was found in the stomach, pylorus and intestine of both species. However, specific activity in pylorus and intestine of threadfin increased 2.75 and 4 times, respectively, but showed little change in trevally. Amlyases were found only in trevally. Increase in lipase specific activity in the gut of trevally was higher than that for threadfin. The results indicated that the two species have diverse digestive capabilities. This appears to be consistent with their feeding habits in nature. Threadfin are more adapted to a wider range of food protein sources than trevally, but appear to be less well adapted than trevally to using complex carbohydrates. These observations may provide a basis for practical diet formulations for these two species.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2109.1999.00407.x
    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...