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
  • 1
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 109 (1998), S. 9434-9438 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The equilibrium structure, potential energy surface and van der Waals (vdW) mode vibration of (N2)2 have been studied with high levels of ab initio calculations. The most stable structure is found to be a 45 deg. canted parallel structure of C2h. On the other hand, neither T-shape of C2v nor cross-shape of D2d is a stable structure, but they are transition state structures, which are contrary to the previous calculations. The out-of-plane motion changing from the 45 deg. canted parallel structure of C2h to the cross-shape of D2d has a higher barrier than the in-plane motion. The binding energy of two N2 monomers is about 80 cm−1 and the fundamental frequency of vdW stretching mode is estimated at 22 cm−1. A small energy difference of 5 cm−1 between the C2h and C2v structures implies that two N2 molecules move coherently like a gear rotation in the plane. This internal freedom of motion should make the rotational energy states extremely modulated, and therefore, a very complex spectrum pattern could be expected. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 115 (2001), S. 6385-6393 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The collision-induced dissociation process, He(1S0)+HF(X 1Σ0+)→He(1S0)+H(2S1/2)+F(2P3/2,1/2), has been studied using a three-dimensional semiclassical coupled wave packet method with a focus on electronically nonadiabatic transitions induced by spin-orbit interaction. The radial motion is described by classical mechanics and the other degrees of freedom are treated quantum mechanically. The diabatic potential energy surfaces have been constructed with the diatomics-in-molecule approach. The diatomic potential energy curves for the ground and excited states are obtained from the ab initio electronic structure calculations at the multireference configuration interaction level. The calculated spin-orbit branching fraction depends only weakly on the initial vibrational quantum number of HF and on the total angular momentum. This implies that the branching fraction is determined mainly in the large-rHF regions where the spin-orbit interaction of the F atom is dominant. We also found that the electronic anisotropy interaction between the He atom and the F atom in HF plays a less important role in collision-induced dissociation processes. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 116 (2002), S. 7065-7072 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The dynamics of the spin-forbidden CH(X 2Π)+N2(X 1Σg+)→HCN(X 1Σ+)+N(4S) reaction has been studied theoretically using the reduced dimensionality quantum scattering method. Three degrees of freedom have been considered in the dynamics calculations by treating CH as a united atom. The problem is thus reduced to the usual atom–diatom scattering calculation. Three-dimensional potential energy surfaces for both the doublet and quartet states were constructed using ab initio electronic structure calculations while the spin–orbit coupling element was taken from previous work. Time-independent quantum reactive scattering calculations have been performed using the hyperspherical close-coupling method. The calculated cumulative reaction probabilities show that the reaction dynamics is exclusively resonance-dominated. The thermal rate constants calculated using the reduced dimensionality cumulative reaction probabilities with the energy shifting and J-shifting approximations were found to be much smaller than experimental measurements and previous reduced-dimensionality results of Seideman [J. Chem. Phys. 101, 3662 (1994)] by a factor of more than two orders of magnitude. In order to understand this serious disagreement, we have carried out the scattering calculations with the use of modified potential energy surfaces and spin–orbit couplings but found that the calculated rate constants were still much smaller than experimental data. The present computational study strongly suggests that further experimental studies including direct detection of N(4S) and/or any other mechanism for the "prompt-NO" formation will be necessary. © 2002 American Institute of Physics.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Physiologia plantarum 96 (1996), S. 0 
    ISSN: 1399-3054
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: We examined changes in the protein composition of cytoplasmic ribosomes in etiolated barley leaves following illumination. Cytoplasmic ribosomes were isolated from greening barley leaves by sucrose density gradient centrifugation, and were analyzed by radical-free highly reducing polyacrylamide gel electrophoresis (RFHR-PAGE). Eighty-nine proteins were resolved from the ribosomal fraction; among them, 8 proteins changed their copy numbers depending on the stage of greening. We designated these as phase dependent ribosomal proteins (PD1–PD8). Two of the proteins (PD1 and 5) present in the ribosomes of etiolated leaves showed a decrease in level during greening. In contrast, the levels of 6 ribosomal proteins (PD2, 3, 4, 6, 7 and 8) increased as greening proceeded. N-terminal amino acid sequence of PD8 showed high homology to rat ribosomal protein L34. The ribosomal proteins that appeared after illumination were not found in any fraction of the etiolated leaves, suggesting that they were synthesized after the onset of illumination. Copy numbers of other ribosomal proteins did not change during greening.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 214 (1967), S. 1358-1360 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] We used aortic oxplants of normocholesteraemic rabbits, weighing 3-3.5 kg, for in vitro cultures in Eagle's basic nutrient enriched with L-glutamine and 15 per cent calf serum. Cultures were observed for 3 weeks to allow the slowly growing smooth muscle cells4 to join the faster growing fibrocytes ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1573-4943
    Keywords: Bovine serum albumin ; helicity ; thermal denaturation ; sodium dodecylsulfate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The helicities in various fragments of bovine serum albumin (BSA) were examined in the thermal denaturation and in sodium docecyl sulfate (SDS) denaturation. The thermal denaturation was examined in a temperature range between 2 and 65°C. The helicity decreased with a rise of temperature and it recovered to some degree upon cooling temperature. A rather high reversibility was observed in the BSA fragments, which were located in the N-terminal of the parent protein and then contained the first large loop with no disulfide bridge. The high reversibility was available also for the helicity in the first large loop of the fragment, disulfide bridges of which were reduced. The fragments, which were smaller than one domain, became unstable in the SDS denaturation. The helicities of such fragments decreased in lower SDS concentrations compared with those of the intact BSA and the large fragments, which contained one or more domains. A resistance to the SDS denaturation appeared in the helices of every large loop even after the fragmentation. On the other hand, helicities of the fragments decreased to 20–25% upon the reduction of disulfide bridges. However, the helicities of these fragments increased to 35–40% in the SDS denaturation.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    The protein journal 8 (1989), S. 653-659 
    ISSN: 1573-4943
    Keywords: bovine serum albumin ; thermal denaturation ; secondary structure ; CD
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The thermal denaturation of bovine serum albumin (BSA) was studied at pH 2.8 and 7.0 in the range of 2–65°C. The relative proportions of α-helix, β-structure, and disordered structure in the protein conformation were determined as a function of temperature, by the curve-fitting method of circular dichroism spectra. With the rise of temperature at pH 7.0, the proportion of α-helix decreased above 30°C and those of β-structure and disordered structure increased in the same temperature range. The structural change was reversible in the temperature range below 45°C. However, the structural change was partially reversible upon cooling to room temperature subsequent to heating at 65°C. On the other hand, the structural change of BSA at pH 2.3 was completely reversible in the temperature range of 2–65°C, probably because the interactions between domains and between subdomains might disappear due to the acid expansion. The secondary structure of disulfide bridges-cleaved BSA remained unchanged during the heat treatment up to 65°C at pH 2.8 and 7.0.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Molecular genetics and genomics 230 (1991), S. 17-23 
    ISSN: 1617-4623
    Keywords: Stationary growth phase ; Promoter selection ; Enzyme modification ; Escherichia coli
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary During the transition of Escherichia coli cultures from exponential growth to stationary phase, the pre-existing RNA polymerase was found to be converted into at least three different holoenzyme forms, which could be separated by phosphocellulose column chromatography. The relative levels of these three holoenzyme forms changed depending on the phase of cell growth. The altered stationary phase forms of RNA polymerase showed promoter recognition properties that were different from those of the holoenzyme from exponentially growing cells. Enzyme reconstitution experiments showed that the altered promoter selectivity was due to modification of the core enzyme. We propose that modulation of RNA polymerase plays a role in the global switch of gene expression during the transition from exponential growth to stationary phase.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2020-07-29
    Print ISSN: 0002-7820
    Electronic ISSN: 1551-2916
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Published by Wiley on behalf of American Ceramic Society.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2016-10-01
    Print ISSN: 0924-4247
    Electronic ISSN: 1873-3069
    Topics: Electrical Engineering, Measurement and Control Technology
    Published by Elsevier
    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...