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排序方式: 共有171条查询结果,搜索用时 31 毫秒
1.
We compute the entropyh
A
(
U
) in the sense of Connes, Narnhofer and Thirring of Bogoliubov automorphisms
U
of the CAR-algebra with respect to invariant quasifree states
A
with 0A1 having pure point spectrum.Supported in part by a grant from the National Science Foundation 相似文献
2.
Juraj Bunta Martin Dahlberg Leif Eriksson Nikolai Korolev Aatto Laaksonen Raimo Lohikoski Alexander Lyubartsev Miroslav Pinak Patric Schyman 《International journal of quantum chemistry》2007,107(2):279-291
This work highlights four different topics in modeling of DNA: (i) the importance of water and ions together with the structure and function of DNA; the hydration structure around the ions appears to be the determining factor in the ion coordination to DNA, as demonstrated in the results of our MD simulations; (ii) how MD simulations can be used to simulate single molecule manipulation experiments as a complement to reveal the structural dynamics of the studied biomolecules; (iii) how damaged DNA can be studied in computer simulations; and (iv) how repair of damaged DNA can be studied theoretically. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007 相似文献
3.
We present solubility and diffusion data for the gases methane and carbon dioxide in the polymer poly(vinylidene fluoride). The polymer was cut from extruded piping intended for use in offshore oil and gas applications. Measurements were carried out using a purpose-built high-pressure microbalance. These properties were determined in the temperature range 80-120 °C and in the pressure range 50-150 bar for methane and 20-40 bar for carbon dioxide. In general, good agreement was obtained for similar measurements reported in the literature. Solubility follows a Henry’s law (linear) dependence with pressure. Diffusion coefficients for each of the gases in the polymer were also measured using the balance. Activation energies for diffusion and heats of solution for the two gases in the polymer were also determined. 相似文献
4.
令X=(n1,n2,…,nt),Y=(m1,m2,…,mt)是两个t维递减序列.如果对所有的j,1≤j≤t,都有∑i=1~j、ni≥∑i=1~j mi以及∑i=1~t ni=∑i=1~t mi,则称X可盖Y,记作X■Y.如果X≠Y,则记作X■Y.本文考虑联图G(n1,n2,…,nt;a)=(Kn1∪n2∪…∪Knt)∨Ka的谱半径,这里n1+n2+…+nt+a=n,(n1,n 相似文献
5.
The extracellular β-xylosidase (EC 3.2.1.37) excreted by the thermophilic eubacteriumRhodothermus marinus when grown on xylan has been investigated. The enzyme has been partially purified by ultrafiltration and gel filtration, and some of its characteristics are presented.Rhodothermus marinus grew on xylan with μmax= 0.4 h? and the α-xylosidase activity was 50 nkat/mL after 24 h in a batch fermentation. The α-xylosidase activity had a half-life of more than 1 h at 90°C and of 14 h at 85 °C. At 80°C, 80% of the initial activity remained after 24 h. The initial activity increased with increasing temperature, showing maximal activity at 90°C. The β-xylosidase had a pH-optimum of 6 and was stable in the range between pH 5 and 9. At pH 10 and 11, 82 and 66%, respectively, of the initial activity remained after 24 h when incubated at 65°C. The molecular weight was estimated to be 169,000 dalton by gelfiltration. 相似文献
6.
7.
Erling Størmer 《Inventiones Mathematicae》1992,110(1):63-73
Summary LetL(F
) be theII
1-factor defined by the free groupF
in infinite number of generators. It is shown that for a class of automorphisms ofL(F
) arising from bijections of the set of generators ofF
on itself, and including the free shift, the entropy is zero.Oblatum 15-III-1992 相似文献
8.
Xiaoyan Liu Karen L. Feilberg Wei Yan Erling H. Stenby 《Journal of Dispersion Science and Technology》2013,34(11):1611-1617
AbstractIn this study, the atomic force microscopy colloidal probe technique was employed to investigate the interaction between apolar, basic and acidic model oil probes and a calcite surface in solutions containing different concentrations of NaCl, CaCl2 and Na2SO4. In the presence of SO42?, hydration and structural forces were observed between apolar model oil probes and a calcite surface on approach. Relatively low adhesion forces were observed between the basic model oil probes and the calcite surface, while higher adhesion forces were observed between the acidic model oil probes and the calcite surface. Furthermore, the adhesion forces between the basic model oil probes and the calcite surface significantly increased in the presence of SO42?, while the adhesion force between the acidic model oil probes and the calcite surface decreased in the presence of Ca2+ or SO42?. The differences in the adhesion forces are related to electrostatic attraction and ion bridging forces between the model oil probes and the calcite surface. 相似文献
9.
Erling Haskjold WencheMarie Olsen Rolf Bjerkens Katherine Kravik 《Photochemistry and photobiology》1993,57(4):663-666
Abstract— The right eyes of 40 rats were exposed to a signal erythemogenic dose fo ultraviolet B irradiation (UVB) at 297nm. The irradiation was directed perpenddicualr to the center of the cornea. The left eyes served as controls. The animals were randomly assigned into 10 groups. The labelling index (LI) after pluse labeling the tritiated thymidine and the mitotic rate (MR) after Colcemid administration were registered in the corneal epithelium at predetermined intervals up to 96 h after the irradiation. A mathematical method was used to corealted corresponding corneal areas from the different animals. In the central the LI was considerably reduced up to 36h after the irradiation. The LI increased toward the peripheral cornea and reached normal values at the limbal area. The MR was also reduced up to 36h. However, this reduction was over the entire epithelium. The block in cell proliferation was followed by increased proliferation. 相似文献
10.
Erling Størmer 《Communications in Mathematical Physics》1970,16(2):136-137
It is shown that the even CAR-algebra over a separable Hilbert space is *-isomorphic to the CAR-algebra. 相似文献