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1.
Hydrodynamic cavitation experiments in microfluidic systems have been performed with an aqueous solution of luminol as the working fluid. In order to identify where and how much reactive radical species are formed by the violent bubble collapse, the resulting chemiluminescent oxidation reaction of luminol was scrutinized downstream of a constriction in the microchannel. An original method was developed in order to map the intensity of chemiluminescence emitted from the micro-flow, allowing us to localize the region where radicals are produced. Time averaged void fraction measurements performed by laser induced fluorescence experiments were also used to determine the cavitation cloud position. The combination void fraction and chemiluminescence two-dimensional mapping demonstrated that the maximum chemiluminescent intensity area was found just downstream of the cavitation clouds. Furthermore, the radical yield can be obtained with our single photon counting technique. The maximum radical production rates of 1.2*107 OH/s and radical production per processed liquid volume of 2.15*1010 HO/l were observed. The proposed technique allows for two-dimensional characterisation of radical production in the microfluidic flow and could be a quick, non-intrusive way to optimise hydrodynamic cavitation reactor design and operating parameters, leading to enhancements in wastewater treatments and other process intensifications. 相似文献
2.
关于绝对半素环和绝对半素根 总被引:3,自引:0,他引:3
张宪君 《纯粹数学与应用数学》1993,9(2):57-60
本文了绝对半素环的概念,研究了绝对半素与与半素环及素环之间的关系,讨论了由全体绝对半素环类决定的上根--绝对半半素根及其性质。 相似文献
3.
Grishin D. F. Semyonycheva L. L. Telegina E. V. Smirnov A. S. Nevodchikov V. I. 《Russian Chemical Bulletin》2003,52(2):505-507
Organometallic compounds Cp2TiCl2, (EtC5H4)2NbCl2, and (PriC5H4)2WCl2 were assessed as additives that control polymer chain growth in the polymerization of methyl methacrylate. In the presence of compounds mentioned in amounts comparable with that of the initiator, a uniform process with no gel-effect occured and respective linear increase in the molecular weight of the polymer up to high degrees of the monomer conversion was observed. 相似文献
4.
Using radical chemistry novel highly condensed heterocycles have been synthesized. The mechanism for their formation is discussed. 相似文献
5.
Zhu Linsheng 《东北数学》1998,(1)
in this paper, the classification and realization of complete Lie algebras withcommutative nilpotent radicals are given. From this, some results on the radicals of thesecomplete Lie algebras are obtained. 相似文献
6.
THE RADICALS OF HOPF MODULE ALGEBRAS 总被引:1,自引:0,他引:1
Zhang Shouchuan 《数学年刊B辑(英文版)》1997,18(4):495-502
THERADICALSOFHOPFMODULEALGEBRASZHANGSHOUCHUAN*AbstractThecharacterizationofH-primeradicalisgiveninmanyways.Meantime,therelati... 相似文献
7.
The thermal rearrangement of trifluoromethyl trifluorovinyl ether (MVE) to pentafluoropropionyl fluoride (PPF) under pressure with and without radical initiators has been studied. The reaction typically gives a mixture of different acyl fluorides. The influence of the reaction parameters (pressure, temperature, concentration, type of initiator and contact time) on the conversion and the selectivity of the process has been carefully examined. In addition, a mechanism which accounts for the formation of all the products has been proposed. 相似文献
8.
François Loiseau Jean-Mary Simone David Carcache Pavel Bobal Reinhard Neier 《Monatshefte für Chemie / Chemical Monthly》2007,138(2):121-129
Summary. Free radical couplings from furan, as cheap starting material, were studied in view of developing a rapid strategy en route to the synthesis of derivatives of nonactin. The chain containing the alcohol function was introduced in one or two steps
in 86% yield. For the introduction of the second chain with the ester function two different coupling methods were tested.
Starting from the advanced intermediates obtained nonactin derivatives can be prepared by catalytic hydrogenation of the furan
ring. 相似文献
9.
用分子轨道从头算方法,对CH自由基的基态(X2Π)和低激发态(a4Σ-)的光谱数据进行了计算.计算结果表明,在基态CH(X2Π)时,在QCISD(T)/6-311G (3df,3pd)水平上,计算所得的键长R=0.1120981nm,偶极矩μ=1.5891 Debye,ν=2845.43cm-1均与实验值相吻合,在B3PW91/6-311G (3df,3pd)理论水平上,计算的基态能量为-38.496143 Hartree,误差仅为0.22%;对低激发态CH(a4Σ-),使用含时的密度泛函方法(TDDFT)和大基组6-311 G(3df,3pd)计算所得的R=0.1094nm,垂直跃迁能量为0.926eV,均与实验结果有较好的吻合. 相似文献
10.
Aryl substituted α-carbonyl bromo-alkynes undergo facile cyclizations to the corresponding substituted 4-methylene-tetrahydrofurans using indium(I) iodide in acetonitrile under sonication in high yields. The reaction is predicted to proceed via a radical process initiated by InI and a plausible radical pathway is suggested. 相似文献