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71.
Kurt Rüfenacht 《Helvetica chimica acta》1975,58(6):1521-1527
Aza-analogues of the known pesticidal dithiophosphates 2, 4 and 5 have been prepared by replacing the phthalimide, benzotriazole and 1,2,3-benzotriazin-4(3H)-one moieties resp. in 2 by those of quinolinic acid imide (6), cinchomeronic acid imide (7) and pyrazine-2,3-dicarboxylic acid imide (12), in 4 by 1H-v-triazolo[4,5-b]pyridine (15) and in 5 by pyrido[2,3-e]1,2,3-triazin-4(3H)-one (21). Compared to the known compounds the new esters are less or at best equally pesticidal with an equal or even higher mammalian toxicity. 相似文献
72.
73.
Prasad V. S. Ika Harry L. Frisch Kurt C. Frisch 《Journal of polymer science. Part A, Polymer chemistry》1985,23(4):1163-1173
The synthesis of crosslinked polydiacetylenes and its two-component interpenetrating polymer networks (IPNs) was carried out utilizing its polar and flexible substituent groups. Polydiacetylenes were crosslinked by the formation of allophanate linkages utilizing urethane groups in the substituent groups of the polydiacetylenes. Elemental analysis, DSC, TMA, solvent resistance, and IR spectra are presented as evidence for the formation of crosslinked polydiacetylenes. IPNs of polydiacetylenes and an epoxy resin (diglycidyl ether of bisphenol A) were synthesized by using simultaneous and sequential methods of synthesis. A study of phase morphology of the simultaneous and sequential IPNs was carried out using electron microscopy, TMA, and DSC. 相似文献
74.
Depending on the N-protecting group of pyroglutamates, the reactivity can be directed to the formation of 6-azabicyclo[3.2.1]octanes or 4-azabicyclo[3.3.0]octanes, which are conformationally restricted glutamate analogues. 相似文献
75.
Kuno Wagner Kurt Findeisen Walter Schfer Werner Dietrich 《Angewandte Chemie (International ed. in English)》1981,20(10):819-830
Research in the field of low-molecular weight, oligomeric and polymeric α,ω-diisocyanatocarbodiimides and -polycarbodiimides has been fruitful, not only in connection with these compounds themselves, but also—as so often happens in chemistry—with quite different problems. Novel synthetic methods, discoveries concerning the properties of low-molecular weight carbodiimides and phosphane imide derivatives, as well as results on the fragmentation reactions of four-membered heterocyclic compounds containing oxygen, phosphorus, and nitrogen, and a better understanding of the diisocyanate polyaddition process are among the many by-products of this research. The “high- and low-temperature formation” of polycarbodiimides and the homogeneous and heterogeneous catalysis of this process are described, and the fundamental importance of four-membered ring fragmentation mechanisms resulting in the formation of phosphane imide derivatives is outlined. Interesting building blocks for the diisocyanate polyaddition and polycondensation processes can be synthesized by many derivatization reactions of oligomeric and high-molecular weight polycarbodiimides and polyuretonimines. The in situ production of polycarbodiimides via matrix reactions in flexible polyurethane foams leads to a cellular arrangement of the material due to the pronounced symmetrical growth processes. Combination-foams with increased carbonation tendencies are formed in this way. Attention is drawn to several industrial applications of α,ω-diisocyanatopolycarbodiimides, of high-molecular weight cross-linked polyuretonimines, and of polycarbodiimide foams. 相似文献
76.
[(Mes3Sn)2MoO4], a Monomeric Triorganotin Molybdate Mes3SnBr (Mes = 1, 3, 5‐trimethylphenyl) reacts with (NBu4)2[Mo6O19] in the presence of (NBu4)OH (in CH3CN as solvent) to form [(Mes3Sn)2MoO4]. Alternatively the title compound can be obtained from the reaction of [MoO2(acac)2] (acac = 2, 4‐pentadionate) with Mes3SnOH in isopropanol. [(Mes3Sn)2MoO4] forms monoclinic crystals, space group C2/c, with a = 2271.6(3) pm, b = 825.2(1) pm, c = 2739.9(5) pm, β = 90.96(2)°. The crystal structure consists of isolated molecules in which a tetrahedral MoO4 unit is connected to two terminal Mes3Sn groups. The Mo‐O distances range from 169.6(4) to 181.1(3) pm and the Sn‐O distance is 204.8(3) pm. 相似文献
77.
Gilar M Fountain KJ Budman Y Neue UD Yardley KR Rainville PD Russell RJ Gebler JC 《Journal of chromatography. A》2002,958(1-2):167-182
An ion-pair reversed-phase HPLC method was evaluated for the separation of synthetic oligonucleotides. Mass transfer in the stationary phase was found to be a major factor contributing to peak broadening on porous C18 stationary phases. A small sorbent particle size (2.5 microm), elevated temperature and a relatively slow flow-rate were utilized to enhance mass transfer. A short 50 mm column allows for an efficient separation up to 30mer oligonucleotides. The separation strategy consists of a shallow linear gradient of organic modifier, optimal initial gradient strength, and the use of an ion-pairing buffer. The triethylammonium acetate ion-pairing mobile phases have been traditionally used for oligonucleotide separations with good result. However, the oligonucleotide retention is affected by its nucleotide composition. We developed a mathematical model for the prediction of oligonucleotide retention from sequence and length. We used the model successfully to select the optimal initial gradient strength for fast HPLC purification of synthetic oligonucleotides. We also utilized ion-pairing mobile phases comprised of triethylamine (TEA) buffered by hexafluoroisopropanol (HFIP). The TEA-HFIP aqueous buffers are useful for a highly efficient and less sequence-dependent separation of heterooligonucleotides. 相似文献
78.
N(SCl)2⊕ [MoCl5(NSCl)]?, a Chlorothionitrene Complex of Molybdenum (VI) . The title compound is formed together with MoCl3(N3S2) by the reaction of MoCl4 or MoCl5 with (NSCl)3 in CH2Cl2. The black, crystalline compound was characterized by its i.r. spectrum and an X-ray crystal structure determination. N(SCl)2⊕[MoCl5(NSCl)]? crystallizes in the monoclinic space group P21/n with four formula units per unit cell. The lattice constants are a = 716.3, b = 1627.4, c = 1178.9 pm and β = 100.90°. The [MoCl5(NSCl)]? ion posseses an almost linear Mo = N = S grouping with bond lengths that can be interpreted as double bonds. Crystal data for AsPh4[MoCl5(NSCl)] are reported. 相似文献
79.
H. Hoffmann 《Fresenius' Journal of Analytical Chemistry》1966,223(5):376
Ohne Zusammenfassung 相似文献
80.
A new synthetic route for the preparation of the betain-like compound (CH3N)6P4F8 from (CH3NPF3)2,N-methyl-hexamethyldisilazane andN,N-dimethyl-urea has been found. The steps of this multi-stage reaction could be rationalized to a far extent.
10. Mitteilung:Kubjacek M., Utvary K., Mh. Chem.112, 305 (1981). 相似文献