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排序方式: 共有885条查询结果,搜索用时 29 毫秒
81.
82.
A selected bibliography on degeneracy problems organized according to the appearance of the respective references in various fields of operations research is given. 相似文献
83.
Martin Månsson Oscar Tjernberg Tomas Claesson Henrik S. Karlsson Ulf O. Karlsson 《Applied Surface Science》2006,252(15):5308-5311
Transiently excited electron states at the GaSb(0 0 1) surface have been studied by means of time- and angle-resolved photoemission spectroscopy based on a femtosecond laser system. A normally unpopulated surface electron state has been found at ∼250 meV above the valence band maximum with a strong confinement at the center of the surface Brillouin zone. The lifetime of transiently excited carriers at the intergap surface states has been found to be ∼11 ps, associated with rapid carrier diffusion. 相似文献
84.
Sverker Fredriksson Magnus Jändel Tomas Larsson 《Zeitschrift fur Physik C Particles and Fields》1982,14(1):35-39
The bulk of data from deep inelasticep, eD, μp, μN, νp and νN scattering is fitted with a new diquark model of nucleons. The proton is found to be mostly in au(ud) 0 state, where the (ud)0 diquark has spin and isospin zero. There is hence no trace ofSU(6) symmetry among diquarks in nucleons. 相似文献
85.
86.
Juan B. Arellano B. Bangar Raju† K. Razi Naqvi Tomas Gillbro‡ 《Photochemistry and photobiology》1998,68(1):84-87
Abstract— In this short communication we present the stoichiometric ratio of bacteriochlorophyll, bacteriopheophytin and carotenoids in a few photosynthetic purple bacteria complexes (whose two-dimensional or three-dimensional structures are well known) determined using the spectrum-reconstruction method (SRCM). An important conclusion of our pigment stoichiometric analysis is the evidence for the absence of the second carotenoid in the light-harvesting complex 2 (LH2). In the process, we also highlight the useful application of SRCM in determining the molar extinction coefficients of carotenoids present in LH1, LH2 or reaction centers for which these values are not known due to isolation problems and/or stability. 相似文献
87.
88.
Predictions of the “redox” and “complex” schemes for the Fe3+ catalyzed decomposition of H2O2 have been compared with published and new experimental data by numerical integratior of the appropriate complete sets of differential equations. Apparent discrepancies for the redox scheme at high Fe3+/H2O2 ratios are shown to disappear in the complete treatment, and inconsistencies of the complex scheme with both kinetic data and spectroscopic measurements are pointed out. 相似文献
89.
90.
Ajay N. Jain Thomas G. Dietterich Richard H. Lathrop David Chapman Roger E. Critchlow Jr. Barr E. Bauer Teresa A. Webster Tomas Lozano-Perez 《Journal of computer-aided molecular design》1994,8(6):635-652
Summary Building predictive models for iterative drug design in the absence of a known target protein structure is an important challenge. We present a novel technique, Compass, that removes a major obstacle to accurate prediction by automatically selecting conformations and alignments of molecules without the benefit of a characterized active site. The technique combines explicit representation of molecular shape with neural network learning methods to produce highly predictive models, even across chemically distinct classes of molecules. We apply the method to predicting human perception of musk odor and show how the resulting models can provide graphical guidance for chemical modifications. 相似文献