ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

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
  • Articles  (217)
  • Articles: DFG German National Licenses  (217)
  • 2005-2009
  • 1990-1994  (217)
  • 1990  (217)
Collection
  • Articles  (217)
Source
Years
  • 2005-2009
  • 1990-1994  (217)
Year
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    BioMetals 3 (1990), S. 67-72 
    ISSN: 1572-8773
    Keywords: Electron transfer ; Electron flow ; Substrate conversion ; Blue copper proteins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Summary Biological electron transfer is not well understood. The question is addressed in this contribution with reference to the so-called blue copper proteins, each of which has a single copper atom at its active centre. The redox activity (as probed by the electron self exchange reaction) of the Cu centre seems not to be affected. The electron self exchange reaction is known to proceed through His-117, and the hydrophobic patch is most important in the formation of the azurin/azurin encounter complex. Ph effects have not been observed on the three-dimensional structure ofA. denitrificans azurin, which may indicate that if present at all these have no direct physiological implications. Mutants are in process of construction.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 35 (1990), S. 660-667 
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A technique was developed to surface immobilize plant cells and was scaled up in laboratory size bioreactors. This technique was shown not to hinder the biosynthetic potential of Catharanthus roseus immobilized cells and to induce a partial release (300 μg/L) of serpentine into the culture medium contrary to suspension cultured cells. The release pattern seemed to follow the biosynthesis trends of the product. This release mechanism could be stimulated by a factor of 10 within 2 h by increasing the pH of the culture from 5.0 to 5.5.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 35 (1990), S. 702-711 
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The scaleup of the technique of plant cell surface immobilization was performed successfully in specifically designed laboratory size bioreactors. The immobilizing matrix was formed into a vertically wound spiral providing for a high immobilizing area-to-volume ratio (0.8-1.2 cm-1). A modified airlift and a mechanically stirred vessel delivered a best bioreactor performance characterized by low biomass frothing and highly efficient plant cell attachment and retention (≥96%). The growth of Catharanthus roseus cells investigated in these bioreactors was found not to be mass transfer limited. It required mild mixing and aeration levels (kLa ∼ 10-15 h-1). The biomass formation pattern of surface immobilized plant cells generally exhibited a linear growth phase followed by a stationary phase characterized by the presence of residual carbohydrates in the medium, contrary to suspension cultures. This behavior was found to depend on the plant cell type and/or line cultured, as well as on the inoculum age. The space restriction and unidirectional growth of the SIPC biofilm combined with the limited availability of essential intracellular nutrients rapidly accumulated from the medium by the stationary phase inoculated plant cells all likely contributed to the culture behavior.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1520-6882
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 93 (1990), S. 9167-9179 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: A microscopic model is presented for anharmonic vibrations of ethylidyne, 3/4 CCH3, chemisorbed on the Pt(111) surface. The model includes 24 vibrational modes of the adsorbate and of the solid. A quantum-mechanical calculation based on second-order perturbation theory is used to interpret experimental data on vibrations of 3/4 CCH3/Pt(111) and 3/4 CCD3/Pt(111). The measured temperature dependence of the CC infrared fundamental and of the umbrella mode fundamental can be accounted for by anharmonic coupling between the CC stretch and the three PtPt stretch coordinates at the base of the adsorbate. Line shapes calculated using classical molecular dynamics disagree significantly with quantum-mechanical results, the apparent reason being overestimation of vibrational energy transfer in the classical calculation. A semiclassical approximation is suggested, in which all the high frequency adsorbate modes except the infrared absorbing mode are frozen; the remaining modes are treated by classical mechanics. The semiclassical calculation agrees much better with the quantum-mechanical results, and can be extended to higher dimension in a straightforward fashion.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 92 (1990), S. 2166-2177 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Laser selective excitation and optical absorption of deuterated SrF2:0.05% Er3+ crystals have revealed eight Er3+ ion centers involving D− ion charge compensation, nine new Er3+–F− centers not associated with D− ions and several approximately cubic symmetry Er3+ centers. In contrast to the trigonal symmetry of the principal F− center, the dominant arrangements in the D− ion charge compensation case are derived from a tetragonal symmetry center. Detailed spectroscopic results for the new centers are presented. Fluorescence polarization ratios are listed for three centers ( J, B, and G1) present in either SrF2:Er3+ or CaF2:Er3+ and crystal-field analyses of these, based on assumed trigonal symmetry, are also reported.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 61 (1990), S. 2354-2359 
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: An easy to operate X-band electron-spin-resonance (ESR) spectrometer capable of operation down to temperatures as low as 0.4 K is described. In contrast to the usual waveguide and cavity setup, a nonmagnetic semirigid coaxial cable and a small loop are used to bring the microwave power down to the 3 He cryostat where a small-helix resonator encloses the sample. The use of a high-gain (18 dB min) and low-noise figure (3.5 dB max) X-band (8–12 GHz) microwave preamplifier in this apparatus permits the detection of a minimum of 1.5×109 spins/G at very low temperature ((approximately-equal-to) 0.4 K), very low microwave power ((approximately-equal-to)0.25 mW), and low modulation frequency (530 Hz). Typical spectra recorded with this spectrometer are also given.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Inorganic chemistry 29 (1990), S. 3139-3145 
    ISSN: 1520-510X
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 56 (1990), S. 2331-2332 
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The leakage current in the semi-insulating substrate of a GaAs device measured in a conventional voltage-controlled experiment shows hysteresis. Experiments in constant-current conditions show that this arises from an S-type negative differential conductivity. These features are incompatible with the conventional trap-fill-limited model, and we outline an alternative explanation based on the impact ionization of multiple deep level traps.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 56 (1990), S. 1916-1918 
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Metal/Langmuir–Blodgett monolayer/metal devices, where the monolayer consists of the dodecyloxyphenylcarbamate of 2-bromo, 5(2'-hydroxyethoxy) tetracyanoquinodimethan, a donor-σ-acceptor molecular system, have been constructed, and dc current-voltage (I-V) characteristics of these devices were recorded at room temperature. For biases of ±20 mV, the I-V characteristics are linear, changing to a nonlinear form for higher voltages. This nonlinear characteristic exhibited a ln(I)∝V1/4 dependence for both positive and negative voltages up to ±1 V. For positive voltages 〉+2.0 V for as-prepared devices and 〉+1.5 V for annealed devices, a ln(I)∝V3 dependence was observed, revealing a very large increase in current for small voltage changes. Such behavior was not observed for corresponding negative voltages, indicating rectification across a distance approximated by the length of an individual molecule.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...