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991.
Corma A Diaz U Domine ME Fornés V 《Angewandte Chemie (International ed. in English)》2000,39(8):1499-1501
992.
M. Davidović D. Arsenović M. Božić A. S. Sanz S. Miret-Artés 《The European physical journal. Special topics》2008,160(1):95-104
The momentum distributions associated with both the wave function of a particle behind a grating and the corresponding Bohmian
trajectories are investigated and compared. Near the grating, it is observed that the former does not depend on the distance
from the grating, while the latter changes with this distance. However, as one moves further apart from the grating, in the
far field, both distributions become identical. 相似文献
993.
In this paper molecular quantum similarity measures (MQSM) are used to describe molecular toxicity and to construct Quantitative Structure-Toxicity Relationships (QSTR) models. This study continues the recently described relationships between MQSM and log P values, which permits to use the theoretical MQSM as an alternative to the empirical hydrophobic parameter in QSPR studies. In addition a new type of MQSM is presented in this work: it is based on the expectation value of electron-electron repulsion energy. The molecular properties studied here, as application examples are aquatic toxicity, toxicology on Bacteria and inhibition of a macromolecule employing four different molecular sets. 相似文献
994.
The optical trapping of nanoparticles and microparticles by a Gaussian standing wave is experimentally demonstrated for the first time to the authors' knowledge. The standing wave is obtained under a microscope objective as a result of the interference of an incoming laser beam and a beam reflected on a microscope slide that has been coated with a system of reflective dielectric layers. Experimental results show that three-dimensional trapping of nanoparticles (100-nm polystyrene spheres) and one or more vertically aligned micro-objects (5-mum polystyrene spheres, yeast cells) can easily be achieved by use of even highly aberrated beams or objectives with low numerical apertures. 相似文献
995.
Andrs Domokos 《Journal of Mathematical Analysis and Applications》1999,230(2):382
Our goal is to show that the continuity of the solutions of monotone variational inequalities with respect to perturbations is independent from the geometrical properties of reflexive Banach spaces. 相似文献
996.
Tamás Szamuely 《K-Theory》1999,18(2):173-179
For a proper smooth variety X defined over a local field k, unramified class field theory investigates the reciprocity map X: SK1(X) ab
1(X) as introduced by S. Saito. We study this map in the case when X is a surface admitting a proper surjection onto a smooth geometrically connected curve C with a smooth conic as generic fibre. Without any assumption on the reduction of C, we prove that X is injective modulo n for all n invertible in k and its cokernel is the same as that of C. 相似文献
997.
Plischke M Vernon DC Joós B Zhou Z 《Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics》1999,60(3):3129-3135
In recent work, we presented evidence that site-diluted triangular central-force networks, at finite temperatures, have a nonzero shear modulus for all concentrations of particles above the geometric percolation concentration p(c). This is in contrast to the zero-temperature case where the (energetic) shear modulus vanishes at a concentration of particles p(r)>p(c). In the present paper we report on analogous simulations of bond-diluted triangular lattices, site-diluted square lattices, and site-diluted simple-cubic lattices. We again find that these systems are rigid for all p>p(c) and that near p(c) the shear modulus mu approximately (p-p(c))(f), where the exponent f approximately 1.3 for two-dimensional lattices and f approximately 2 for the simple-cubic case. These results support the conjecture of de Gennes that the diluted central-force network is in the same universality class as the random resistor network. We present approximate renormalization group calculations that also lead to this conclusion. 相似文献
998.
The parasitic effect of two-ion up-conversion in Er3+ -doped fibers have been investigated. Maximum amplification for eight different Er3+ concentrations have been measured and it is shown that up-conversion drastically reduces amplification for Er3+ concentrations in the range of 140-1680 ppm by weight. We have also measured an up-conversion induced luminescence at 980 nm. By comparison of experimental and simulated characteristics, we obtain an up-conversion coefficient of 10-22 m3/s. 相似文献
999.
1000.