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84.
Wladyslaw Reimschüssel Halina Abramczyk Jacek Michalak 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):201-211
Abstract 2-Chloro-5,5-dimethyl-2-oxo-1,3,2-dioxaphosphorinane has been studied in CCl4, CHCl3 and CD3CN solutions by IR and Raman line shape analysis. Equilibrium process of dimerization and ring conversion in CCl4 solutions have been considered. On the contrary to the commonly expected dominance of the conformer with the equatorial oriented P[dbnd]O bond for 2-halo-2-oxo-1,3,2-dioxaphosphorinanes, it was found that for the 2-chloro derivative both conformers are nearly equally distributed. It has been shown that the interactions induced absorption is an important mechanism of relaxation in the studied compound and this mechanism gives significant contribution to the total IR band broadening, while the interaction induced light scattering is negligible. The obtained results show that the molecular dynamics method can be useful in studying cyclic compounds in solutions. 相似文献
85.
Jacek E. Nycz 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2605-2612
The present study shows new aspects of the synthesis of polyhalogenoarylphosphanes. The sterically hindered anions Ph(R)P-Y? (1a–c, Y = O, lone pair; R = Ph, But) have been used to show the complexity of the reaction between phosphorus nucleophiles and hexahalogenobenzenes or 9-bromofluorene (E3). The Ph(But)P-O? (1a) anion reacts with hexachlorobenzene (E1), hexafluorobenzene (E2), or E3 to give Ph(R)P(O)X (4a–c, X = F, Cl, Br) with the release of the corresponding carbanion as a nucleofuge, followed by side reactions. In contrast, the lithium phosphides Ph(R)PLi (1b,c) react with hexahalogenobenzenes to give the corresponding diphosphanes 5a,b as the main product and traces of P-arylated products, i.e., Ph(R)P-C6X5 (10a,b, X = Cl, F). Unexpectedly, Ph(But)PLi (1b) reacts with an excess of 9-bromofluorene to give only halogenophosphane Ph(But)P-X. 相似文献
86.
Annia H. Kycia Kallum Koczkur J. Jay Leitch Jacek Lipkowski Vlad Zamlynny Michael W. P. Petryk 《Analytical and bioanalytical chemistry》2013,405(5):1537-1546
Polarization modulation–infrared reflection absorption spectroscopy (PM-IRRAS) was employed to analyze two unique samples: (1) an industrially prepared alkoxysilane-pretreated aluminum alloy (AA6111) in the absence and presence of a ~600-nm-thick lubricant coating and (2) a chemical warfare agent simulant, triethyl phosphate (TEP), on glass. For the pretreated aluminum samples, PM-IRRAS spectra were analyzed for three distinct regions; the SiO stretching vibration around 1120 cm?1, the NH2 bending mode at ~1600 cm?1 and the CH stretching region around 2900 cm?1. Our results showed that increasing the curing temperature (from 55 to 100 °C) improved the overall extent of cross-linking within the siloxane network. In addition, the spectra of lubricant (top coating) and the underlying siloxane layer for the aluminum samples with lubricant were collected for the same sample. Our results show that the nature of the siloxane film remains intact and unaltered after deposition of the lubricant top-coat. For detection of TEP on glass, the band at 1268 cm?1, corresponding to the P═O vibration, was monitored. A droplet of TEP solution in dichloromethane was deposited on glass. After solvent evaporation had occurred, the intensity of the P═O vibration band was used to construct calibration curves to determine the experimental limit of detection, which was found to be ~200 μg for TEP on glass. Figure
Schematic of a akoxysilane network and PM-IRRAS spectrum of the alkoxysilane film at aluminum surface 相似文献
87.
Abstract: Synthesis of bis(2-chlorosulfonylphenyl) diselenide (11) from 2-amino-benzenesulfonic acid was elaborated. It was shown that (11) is a good starting material for synthesis of the organoselenium sulfonamides, such as bis(2-sulfamoylphenyl) diselenides (3) and benz-2,3-azaselenathiophene 1,1-dioxides (4), being potential immunostimulants and oxidation catalysts. 相似文献
88.
Synthesis of two new groups of organoselenium compounds: 2-acyl-and sulfonylbenzisoselenazol-3(2H)-ones (3, 4), potential immunostimulants, in two alternative ways was elaborated. One of them was based on the reaction of 2-chlorobenzoyl chloride (2) with primary amides while the second one involved N-acylation or N-sulfonylation of benzisoselenazol-3(2H)-one (5) with acid chlorides. Two exceptions from general reaction of dichloride 2 with amides were observed. Thioacetamide produced 2,1-benzothiaselenophenone (6), and urea gave 6,7-benzo-2,4-diaza-1-selenacyclohepta-3,5-dione (7). 相似文献
89.
Jacek Grodner 《合成通讯》2013,43(7):919-924
The main component of the sex pheromone of many lepidopteran pests, (2E,13Z)‐2,13‐octadecadienyl acetate (1), has been synthesized following a simple route using 12‐(2‐tetrahydropyranyloxy)‐1‐dodecyne (2) as the starting material. 相似文献
90.
The catalytic oxidative domino degradation of phenols was investigated. Hydrogen peroxide (30% aq.) was used as an oxidant and 2,2′-dinitro-4,4′-ditrifluoromethyldiphenyl diselenide 4e as a catalyst. The products were muconic acid 5, and muconolactones muconolactones—5-carboxymethylfuran-2(5H)-ones 7 and 9. Phenols with alkyl groups at 2 or 4 positions of the benzene ring were converted regioselectively to corresponding muconolactones substituted at alkenylene ring carbon atoms. The reaction mechanism is proposed. 相似文献