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
  • 2005-2009  (41)
  • 2000-2004  (47)
  • 1995-1999  (36)
  • 1925-1929  (5)
  • 1910-1914  (3)
  • 1
    Electronic Resource
    Electronic Resource
    Minority-carrier kinetics in heavily doped GaAs:C studied by transient photoluminescence (2002)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 91 (2002), S. 5072-5078 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Room-temperature photoluminescence decay time measurements in heavily doped GaAs:C-layers designed as base layers for heterojunction bipolar transistors are reported. These measurements provide access to nonequilibrium minority carrier lifetimes that determine the current gains of those devices. By systematically studying transient luminescence spectra over a wide range of excitation densities between 1013 and 1018 cm−3, we demonstrate the importance of carrier trapping processes at low excitation densities. Optimized excitation conditions that achieve trap saturation but also avoid stimulated emission are found for densities of (1–3)×1017 cm−3/pulse. Detection is limited to a spectral window well above the energy gap (beyond 1.5 eV). Values for both Auger and radiative recombination coefficients are given. © 2002 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1456244
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Polarisationserscheinungen bei der stufenweisen Anregung der Fluoreszenz von Quecksilberdampf (1929)
    Springer
    The European physical journal 54 (1929), S. 811-818 
    Details
    ISSN: 1434-601X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Zusammenfassung Die Fluoreszenz des Quecksilberdampfes bei polarisierter stufenweiser Anregung mit den Linien 2537 und 4047 unter Stickstoffzusatz wird untersucht und die dabei auftretenden Polarisationseffekte und Intensitätsversehiebungen der Fluoreszenzlinien 5461, 4358 und 4047 werden beschrieben und erklärt. Einige wichtige Folgerungen und weitere Untersuchungsmöglichkeiten werden diskutiert.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01341742
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Effect of Carbon and Nitrogen Implantation on the Properties of Silicon Nitrides (2005)
    s.l. ; Stafa-Zurich, Switzerland
    Key engineering materials Vol. 290 (July 2005), p. 160-166 
    Details
    ISSN: 1013-9826
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: This study focused on the effect of ion implantation on the mechanical properties ofsilicon nitride based ceramics. The examined materials contained 4% Al2O3, 6% Y2O3 and, in some cases, graphite or black carbon additives. Fully densified bodies were manufactured by two-step hot isostatic pressing, in other experiments pressureless sintering gave porous ceramics. Nitrogen or carbon ions with 190 keV or 350 keV were implanted, a part of samples obtained laser treatments for comparison. Measurements of elastic modulus, four point and three point bending strength were carried out at room temperature on sintered samples, partially sintered samples and sintered and oxidised samples. Carbon or nitrogen implantation influenced the strength of partially sintered samples only if the density was over 80%. Both the implantation of carbon or nitrogen ions and the laser treatment affected the bend strength of sintered samples, enlarging the power introduced itsvalue first increased than decreased. Implantation slightly decreased the strength of samples oxidised at 1400 °C. Comparison of different mechanical characteristics may support a better understanding of phenomena during ion beam implantation or laser irradiation
    Type of Medium: Electronic Resource
    URL: http://www.tib-hannover.de/fulltexts/2011/0528/01/49/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.290.160.pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Separation of the reaction products of cyanazine and terbuthylazine nitrosation by thin-layer chromatography (1998)
    Springer
    Fresenius' journal of analytical chemistry 360 (1998), S. 679-682 
    Details
    ISSN: 1432-1130
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract N-Nitroso-triazine herbicide species were synthesized as reference standards and their reaction products were separated by TLC. The method was established for analytical as well as for preparative amounts to achieve a sufficient separation between the educts, the byproducts and the N-nitrosated moieties. Separation of the reaction mixture was performed by two-dimensional TLC, using different mobile phases for each dimension. In the second dimension two developments were executed using the same solvent mixture. To examine the quality of performance, the separation zones were scrapped off, extracted and analyzed in the HPLC-diode array detection (DAD) mode in comparison with standards of the educts and the products of their N-nitrosation. This method minimizes the contact with the resulting N-nitroso compounds. At present nothing is known about the toxicological relevance or risk assessment on human health of N-nitrosocyanazine or N-nitrosoterbuthylazine species. Therefore the practical handling of these putative mutagenic and carcinogenic substances should be seen under the aspect of precaution and prevention of contamination.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002160050780
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Gold electrodes from recordable CDs for mercury quantification by flow injection analysis (2000)
    Springer
    Fresenius' journal of analytical chemistry 366 (2000), S. 444-448 
    Details
    ISSN: 1432-1130
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The development of a new methodology for the construction of very efficient flow cells for mercury detection by potentiometric stripping analysis, employing the thin gold layer of recordable CDs as working ¶electrode is reported. This new source of electrodes (CDtrodes) show very attractive performance, similar to that obtained with commercial gold electrodes, with superior versatility. The low cost of this new source of “gold electrodes” allows a frequent replacement of the electrode, avoiding cumbersome clean-up treatments. Various experimental parameters have been optimized to yield low detection limits (0.25 ng/mL of mercury for 5 min deposition at 0.3 V) and good precision (standard deviation of 1.9% was obtained for 15 repetitive measurements using 10 ng/mL of mercury). Standard curves were found to be linear over the range of 0.5–100 μg L–1 of mercury. The flow cells developed were used for the quantification of mercury in oceanic and tap water.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002160050090
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Hydroxyapatite nucleation on Na ion implanted Ti surfaces (2000)
    Springer
    Journal of materials science 19 (2000), S. 1029-1031 
    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/10.1023/A:1006782818468
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Gas-sensor properties of SnO2 films implanted with gold and iron ions (1997)
    Springer
    Journal of materials science 8 (1997), S. 301-306 
    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 SnO2 gas-sensor films were modified by implantation of gold and iron ions. The change in electrical resistivity of the films caused by inflammable gases, H2, CO, CH4 and C2H5OH, was measured in the temperature range 100–500°C, and compared to non-implanted films. The morphological changes caused by gold and iron ion implantation were also investigated by atomic force microscopy. After ion implantation and annealing at 600°C, the sensitivity to H2 and CO gas was found to increase, and the dynamic range of the sensitivity to ethanol was improved. The sensitivity to CH4 was low before and after ion implantation. Fe2O3 (3%SnO2) film was also modified by gold ion implantation for comparison.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1018535322380
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Growth of anchorage-dependent mammalian cells on microstructures and microperforated silicon membranes (1996)
    Springer
    Journal of materials science 7 (1996), S. 85-97 
    Details
    ISSN: 1573-4838
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Anchorage-dependent cells (mouse fibroblasts L929 and 3T3) were cultivated on microstructures made by semiconductor technology. Both cell lines showed normal growth on silicon surfaces covered with microelectrode arrays as well as on microperforated silicon membranes with square pores made by anisotropic etching (5, 10 or 20 μm edge length at the top and 1.2, 6.2 or 16.2 μm at the bottom). The cells spread over the 5 and 10 μm pores, but mostly failed to cover the 20 μm ones. They were able to cross the silicon membrane through the pores and to grow and spread on the under side of the membrane. Small pores (about 1 μm2) impeded but did not prevent cells crossing the membrane. Medium and large pores were freely crossed. Negative dielectrophoresis was used to achieve accurate positioning of cells above pores or to repel them from the chip surface (a.c., square wave, 2.5 V peak-to-peak, 5 MHz). The results are discussed with respect to their microtool applications for single-cell technologies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00058719
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Surface sensitivity of ion implanted titanium to hydroxyapatite formation (2000)
    Springer
    Journal of materials science 19 (2000), S. 443-445 
    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/10.1023/A:1006759309358
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Investigation of Fe-Mg-Alloys Produced by Ion Implantation (1998)
    Springer
    Hyperfine interactions 112 (1998), S. 165-168 
    Details
    ISSN: 1572-9540
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Iron and magnesium are insoluble elements with each other and there is no phase diagram. However, it is possible to produce artificial alloys by ion implantation, in this study by iron implantation into magnesium. Samples are investigated by conversion electron Moessbauer spectroscopy, Auger electron spectroscopy and x-ray diffraction. While at low doses gaussian shaped iron profiles and paramagnetic doublets as Mössbauer spectra are obtained, the iron concentration reaches at the highest dose 90 at.-% in maximum and the Mössbauer spectrum shows a dominant ferromagnetic fraction. The x-ray diffraction pattern let conclude that a dilated α-iron lattice is formed. Microhardness of all samples is clearly increased due to the implantation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1011021618496
    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...