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71.
Mizuho Nisizawa 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(5):925-931
Amino acids, proteins, vitamins, chelating agents, and S-containing compounds were found to protect the shape of the external envelope of the protein molecule from radiation damage. The behavior of the viscosity change closely resembles that found with sodium glutamate and sodium benzoate, as shown by a similar dependence on the concentration. Protein irradiated by γ-rays showed the effect of temperature on changes in the shape of the external envelope of the protein molecule. The behavior of the viscosity change was studied. 相似文献
72.
Mizuho Nisizawa 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(5):939-944
The radiation protective effect of the breaking of secondary bonding in proteins was examined with 1,2 diamine and 1,2 dihydroxy derivatives such as ethylenediamine, ethylenediaminetetraacetic acid, and propylene glycol, and monosubstituted amines and alcohols such as ethylamine and n-propyl alcohol. An empirical equation for the viscosity change was obtained. 相似文献
73.
Polymer-bound alkylthiopurine and -pyrimidine bases were prepared and used as the polymeric reagents for the reactions of nitrile, olefin, and enone formation. The corresponding low molecular weight compounds were also prepared for comparison. Differences in the reactivity of these reagents were related to the change in tautomerism of the purine and pyrimidine moieties. 相似文献
74.
Maki Sachiko Eiji Nishibori Shinobu Aoyagi Makoto Sakata Masaki Takata Mio Kondo Masaki Murata Ryota Sakamoto Hiroshi Nishihara 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(7):696-703
The title compound, [Fe2(C5H5)2(C40H22O2)] or 1,4‐(FcPh)2Aq [where FcPh is 2‐(4‐ferrocenylphenyl)ethynyl and Aq is anthraquinone], was synthesized in an attempt to obtain a new solvent‐incorporating porous material with a large void space. Thermodynamic data for 1,4‐(FcPh)2Aq show a phase transition at approximately 430 K. The crystal structure of solvent‐free 1,4‐(FcPh)2Aq was determined at temperatures of 90, 300 and 500 K using synchrotron powder diffraction data. A direct‐space method using a genetic algorithm was employed for structure solution. Charge densities calculated from observed structure factors by the maximum entropy method were employed for model improvement. The final models were obtained through multistage Rietveld refinements. In both phases, the structures of which differ only subtly, the planar Aq fragments are stacked alternately in opposite orientations, forming a one‐dimensional column. The FcPh arms lie between the stacks and fill the remaining space, leaving no voids. C—H...π interactions between the Ph and Fc fragments mediate crystal packing and stabilization. 相似文献
75.
Yoshikata Koga Takemi Kondo Yuji Miyazaki Akira Inaba 《Journal of solution chemistry》2012,41(8):1388-1400
Using the 1-propanol (1P) probing methodology we have developed earlier, we characterized the effects of sulphate and tartrate anions on the molecular organization of H2O. The results indicate that these two large anions belong to a new class of ??hydrophobe-like hydration center??. That is, sulphate and tartrate ions act as ??hydration centers?? with the hydration number 14±3 for both, and leave the bulk H2O, away from hydration shells, unperturbed in the absence of the probing 1-propanol. As the mole fraction of the probe increases, however, the hydrogen bond probability of bulk H2O away from hydration shells appears to decrease smoothly, as occurs with ??hydrophobes?? in H2O. We plot the negative hydration number against the power to reduce the hydrogen bond probability of bulk H2O for the two large anions. We also plotted the characteristic indices for ??hydrophiles?? and ??hydration centers?? whose characteristics we determined in the same manner earlier. H2O defines the origin on this map. We found that a typical Hofmeister ranking for each anion matches reasonably well with that of the distance from the origin for each ion, in decreasing order starting from ions plotted in the north-west quadrant (representing the ??hydrophobe-like?? behavior) of the map and then in increasing order from the origin towards the south on the ordinate, the ??hydrophile-like?? behavior. These findings could be useful in understanding the Hofmeister series, pointing to the importance of the contribution made by the effect of each ion on H2O, in addition to helping understand direct ion-protein interactions. 相似文献
76.
Abstract Color centers in rutile-structured MgF2 single crystals irradiated at 20K/360K by reactor neutrons are investigated spectroscopically at LNT. Four different types of the F-F vacancy bond in MgF2 are possibly identified to the observed absorption bands as due to the F2 centers; instead of previous assignments, the 300nm band to the F2(D2h), the 325nm band to the F2(C1), the 355nm band to the F2(C2v), and the 400nm band to the F2(C2h) centers. 相似文献
77.
Shin-ichi Kondo Kimihiro Endo Jun Iioka Keisuke Sato Yuka Matsuta 《Tetrahedron letters》2017,58(43):4115-4118
We have successfully prepared 5-(2-phenylethynyl)isophathalilc acid as a signaling unit and the corresponding derivatives for an anion receptor 2 and a barbiturate receptor 4. Receptor 2 showed characteristic UV–vis changes and dramatic fluorescence quenching upon the addition of anions and receptor 4 showed UV–vis and an OFF-ON fluorescence changes upon the addition of dibutylbarbituric acid based on the diphenylethyne moiety. 相似文献
78.
The photoinitiating ability of some sulfur ylides was studied. Diphenylsulfonium bis (methoxycarbony1)methylide (DPSY) could photoinitiate methyl methacrylate and styrene. A free radical mechanism was confirmed by a kinetic study, the inhibiting effect of benzoquinone, and the copolymer composition. From an analysis of the photodecomposition products it is suggested that the phenyl radical generated from the bond fission between the sulfur atom and the phenyl group participates in the initiation of this free radical polymerization. Methylphenylsulfonium bis (methoxycarbonyl) methylide, as well as DPSY, served as a photoinitiator, but dimethylsulfonium bis (methoxycarbony1)methylide did not. The differences are explained based on UV spectra. 相似文献
79.
Mizuho Nisizawa 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(5):909-918
When protein in various liquids containing aromatic hydrocarbons, such as benzene, naphthalene, and phenanthrene, is irradiated by γ-rays from a 60Co source the changes in the internal relationships of the atoms in the protein molecule vary with the irradiation liquids containing aromatic hydrocarbons. An empirical equation for the optical rotation was obtained, and the phenomena were explained on the basis of the molecular mechanism. Protein irradiated by γ-rays from a 60Co source in air showed the effect of pH on the changes in the internal relationships of the atoms in the protein molecule. An empirical equation for the optical rotation was obtained, and the phenomena were explained on the basis of the molecular mechanism. 相似文献
80.