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11.
A perylene bisimide derivative bearing two phenyl substituents with chiral solubilizing alkyl chains at the imide N atoms has been synthesized, and its self-assembly properties in solution and condensed phase have been investigated. Temperature-dependent CD spectra revealed the coexistence of two different kinds of chiral aggregates, differing in size and handedness. The chiral side chains effect a higher order within the self-assemblies, resulting in an increased charge-carrier mobility in the columnar liquid crystalline mesophase. [structure: see text] 相似文献
12.
13.
William R. Adams John A. Zollweg William B. Strett Walter G. Chapman Paulette Clancy 《Fluid Phase Equilibria》1988,40(3):247-257
Measurements of the excess enthalpy of krypton and xenon mixtures at 163 K are reported. These results are found to disagree with the only other published result. This discrepancy is discussed. Conformal solution theory is used to provide an unbiased prediction of the excess enthalpy. We review published experimental and calculated excess thermodynamic properties of the Kr/Xe system at zero pressure and 161.38 K and 165 K. 相似文献
14.
Silke Schmetzer Paulette Greenidge Karl-Artur Kovar Meike Schulze-Alexandru Gerd Folkers 《Journal of computer-aided molecular design》1997,11(3):278-292
A cannabinoid pseudoreceptor model for the CB1-receptor has been constructed for 31 cannabinoids using the molecular modelling software YAK. Additionally, two CoMFA studies were performed on these ligands, the first of which was conducted prior to the building of the pseudoreceptor. Its pharmacophore is identical with the initial superposition of ligands used for pseudoreceptor construction. In contrast, the ligand alignment for the second CoMFA study was taken directly from the final cannabinoid pseudoreceptor model. This altered alignment gives markedly improved cross-validated r2 values as compared to those obtained from the original alignment with
values of 0.79 and 0.63, respectively, for five components. However, the pharmacophore alignment has the better predictive ability. Both the CoMFA and pseudoreceptor methods predict the free energy of binding of test ligands well. 相似文献
15.
Salvagnini C Michaux C Remiche J Wouters J Charlier P Marchand-Brynaert J 《Organic & biomolecular chemistry》2005,3(23):4209-4220
Piperazinyl-amide derivatives of N-alpha-(3-trifluoromethyl-benzenesulfonyl)-L-arginine (1) were synthesized as graftable thrombin inhibitors. The possible disturbance of biological activity due to a variable spacer-arm fixed on the N-4 piperazinyl position was evaluated in vitro, against human alpha-thrombin, and in blood coagulation assay. Molecular modelling (in silico analysis) and X-ray diffraction studies of thrombin-inhibitor complexes were also performed. The fixation of bioactive molecules on poly(butylene terephthalate) (PBT) and poly(ethylene terephthalate) (PET) membranes was performed by wet chemistry treatment and evaluated by XPS analysis. Surface grafting of inhibitor 1d improved the membrane hemocompatibility by reducing blood clot formation on the modified surface. 相似文献
16.
Michael Küttinger Paulette A. Loichet Torres Emeline Meyer Dr. Peter Fischer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(13):e202103491
Bromine complexing agents (BCA) in aqueous electrolytes for hydrogen bromine flow batteries are used to reduce bromine‘s vapour pressure, while an insoluble and liquid fused salt is formed. The properties (concentrations, composition, conductivity and viscosity) of this fused salt are investigated in this study systematically ex situ by using 7 BCAs at different state of charge in HBr/Br2/H2O electrolytes with a theoretical capacity of 179.6 Ah L−1. Bromine is stored in the fused salt at concentrations up to 13.6 M, reaching theoretical volumetrical capacities up to 730 Ah L−1 in fused salts. The fused salt consists of a pure, bromine- and water-free ionic liquid of organic [BCA]+ cations and polybromides, and its conductivity bases on a hopping mechanism among the polybromides. Alkyl side chain length of the BCAs and distribution of polybromides influence strongly the conductivity and viscosity of the fused salts. 1-ethylpyridin-1-iumbromide results to be favoured BCA for application. 相似文献
17.
3H-benzothieno[3,2-d]pyrimidin-4-one (3) was synthesized by bimolecular cyclising the 3-amino-2-carbethoxybenzothiophene (1) with formamide. The electrophilic substituion of 3 afforded N-methylated lactam derivavtives, the structure of which was assigned by 'H nmr and unequivocal synthesis. The sysnthesis of benzothieno[3,2-d]pyrimidine (7) was achieved by desulphurization of the 3H-benzothieno[3,2-d]-[3,2-d]pyrimisine-4-thione (6) or by oxydation of the 4-hydrazinobenzothieno[3,2-d]primidine (5). 相似文献
18.
Virtual samples of approximations to real amorphous silicon, a-Si, have been prepared using several different processing routes. These include a fast quench from the melt followed by a long slow annealing period using molecular dynamics, a Reverse Monte Carlo approach, and an ab initio minimization. The characterization of these virtual a-Si samples includes a consideration of structural data (the radial distribution function, angular order, etc.), electronic properties (through the density of states), and thermodynamic information (chiefly the nature of the phase transformation from a-Si to liquid). The properties of a-Si are compared to network models, via the continuous random network model, and to experiment. We investigated the stability of virtual a-Si and consider its implications for use in future simulation studies. We have demonstrated the necessity for the accuracy provided by ab initio-based models to describe the interatomic potentials. Throughout this study, we have monitored the role of order in determining physical properties, as characterized by traditional routes (such as angular correlations) and more novel ones (the signature cell method). 相似文献
19.
Paulette Collum Richard S. Egan Alma W. Goldstein Jerry R. Martin 《Tetrahedron》1976,32(20):2375-2378
3-O-(2″,6″-Dideoxy-α-l-ribo-hexopyranosyl)erythronolide B (6) and 3-O-(2″,6″-dideoxy-α-l-arabino-hexopyranosyl)erythronolide B (7), aberrant metabolites of erythromycin biosynthesis, have been isolated from the fermentation broth of a blocked mutant of the erythromycin producing organism Streptomyces erythreus. The defective glycosidesm, when incubated with early blocked mutants of S. erythreus capable of converting authentic erythromycin progenitors to the complete antibiotic, were unmetabolized. The probable origin of the metabolite is discussed. 相似文献
20.
Paulette Libermann 《Annali di Matematica Pura ed Applicata》1954,36(1):27-120
Résumé Après avoir rappelé la définition et quelques propriétés des pseudogroupes de Lie, on définit les structures infinitésimales
régulières. On peut toujours associer des connexions affines à de telles structures; courbure et torsion de ces connexions.
Equivalence locale de deux structures infinitésimales. Application à l'étude des structures presque complexes, presque paracomplexes,
presque symplectiques, presque hermitiennes, presque parahermitiennes, presque quaternioniennes, presque quaternioniennes
de deuxième espèce. 相似文献