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71.
Simone Manzini Dr. Albert Poater Dr. David J. Nelson Prof. Dr. Luigi Cavallo Prof. Dr. Alexandra M. Z. Slawin Prof. Dr. Steven P. Nolan 《Angewandte Chemie (International ed. in English)》2014,53(34):8995-8999
The decomposition of a series of benzylidene, methylidene, and 3‐phenylindenylidene complexes has been probed in alcohol solution in the presence of base. Tricyclohexylphosphane‐containing precatalysts are shown to yield [RuCl(H)(H2)(PCy3)2] in isopropyl alcohol solutions, while 3‐phenylindenylidene complexes lead to η5‐(3‐phenyl)indenyl products. The potential‐energy surfaces for the formation of the latter species have been probed using density functional theory studies. 相似文献
72.
Facile Insertion of Carbon Dioxide into Cu2(μ‐H) Dinuclear Units Supported by Tetraphosphine Ligands 下载免费PDF全文
Kanako Nakamae Dr. Bunsho Kure Prof. Takayuki Nakajima Prof. Yasuyuki Ura Prof. Tomoaki Tanase 《化学:亚洲杂志》2014,9(11):3106-3110
Reactions of meso‐bis[(diphenylphosphinomethyl)phenylphosphino]methane (dpmppm) with CuI species in the presence of NaBH4 afforded di‐ and tetranuclear copper hydride complexes, [Cu2(μ‐H)(μ‐dpmppm)2]X ( 1 ) and [Cu4(μ‐H)2(μ4‐H)(μ‐dpmppm)2]X ( 2 ) (X=BF4, PF6). Complex 1 undergoes facile insertion of CO2 (1 atm) at room temperature, leading to a formate‐bridged dicopper complex [Cu2(μ‐HCOO)(dpmppm)2]X ( 3 ). The experimental and DFT theoretical studies clearly demonstrate that CO2 insertion into the Cu2(μ‐H) unit occurred with the flexible dicopper platform. Complex 2 also undergoes CO2 insertion to give a formate‐bridged complex, [Cu4(μ‐HCOO)3(dpmppm)2]X, during which the square Cu4 framework opened up to a linear tetranuclear chain. 相似文献
73.
《Journal of Energy Chemistry》2014,23(4):414-419
Alkali metal hydroxide and hydride composite systems contain both protic(H bonded with O) and hydridic hydrogen. The interaction of these two types of hydrides produces hydrogen. The enthalpy of dehydrogenation increased with the increase of atomic number of alkali metals,i.e.,-23 kJ/molH2 for LiOH-LiH, 55.34 kJ/molH2 for NaOH-NaH and 222 kJ/molH2 for KOH-KH. These thermodynamic calculation results were consistent with our experimental results. H2 was released from LiOH-LiH system during ball milling. The dehydrogenation temperature of NaOH-NaH system was about 150℃; whereas KOH and KH did not interact with each other during the heating process. Instead, KH decomposed by itself. In these three systems, NaOH-NaH was the only reversible hydrogen storage system, the enthalpy of dehydrogenation was about 55.65 kJ/molH2, and the corresponding entropy was ca. 101.23 J/(molH2 K), so the temperature for releasing 1.0 bar H2 was as high as 518℃, showing unfavorable thermodynamic properties. The activation energy for hydrogen desorption of NaOH-NaH was found to be57.87 kJ/mol, showing good kinetic properties. 相似文献
74.
Several five‐membered heterocyclic molecules were studied theoretically as organic hydride donors. The density functional theory and ab initio methods are employed to study the direct one‐step or multistep sequence suggested for the hydride transfer from the selected molecules: H atom/electron, electron/proton/electron or electron/H atom. Out of the three multistep mechanisms, electron/H atom seems to be a probable pathway in the presence of suitable catalyst/photoreaction that can cause ionization. In the lack of such catalyst/photoreaction, the direct hydride transfer seems to be most probable with the presence of suitable hydride acceptor. A detailed mechanism of the hydride transfer from the five‐membered heterocylic compounds is important in understanding chemical and biological reactions and required for scientifically designing and synthesizing new desired five‐membered heterocyclic compounds as organic hydride donor. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
75.
本文基于粒子群优化算法的结构预测方法结合第一性原理计算,研究了LiYH4,Li2YH5和Li3YH6在0—300 GPa压力范围内的晶体结构、电子结构、热力学和动力学稳定性.研究结果表明LiYH4-P4/nmm,Li2YH5-I4/mmm和Li3YH6-P4/nmm结构可分别在169—221 GPa,141—300 GPa和166—300 GPa压力范围内由LiH和YH3按一定配比加压合成.富氢化合物的超导电性研究成为近年来高温超导体研究领域的热点,该研究结果有希望为Li-Y-H三元体系氢化物的超导电性研究及实验合成提供数据支撑. 相似文献
76.
Duc Hanh Nguyen Frdric Hebrard Josep Duran Alfonso Polo Martine Urrutigoíty Philippe Kalck 《应用有机金属化学》2005,19(1):30-34
Three different kinds of representative monoterpenic alcohol are involved in the palladium‐catalysed cyclocarbonylation reaction. Lactone formation is shown to occur when cyclic ( 1 ), tertiary ( 3 ) and primary allylic alcohol ( 7 ) functions are reacted, in the presence of CO with [HPd(SnCl3)L2] as the active catalytic species. Good yields and selectivities can easily be reached for isopulegol ( 1 ), and dihydromyrcenol ( 3 ). However, more modest results are obtained for the functionalization of geraniol into the original lactone ( 9 ). This lactone can be largely favoured by using a basic chelating diphosphine ligand such as 1,4‐bis(diphenylphosphino)butane. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
77.
Elmar Hecht 《应用有机金属化学》2005,19(3):390-390
Dimeric and centrosymmetric [MeEtN(CH2)3AlH2]2 comprises aluminum centers, coordinated in a distorted trigonal bipyramidal fashion by three hydrogen atoms, one nitrogen atom and one carbon atom. The aluminum atoms are bridged by hydrogen atoms, creating a planar, four‐membered Al2H2 ring. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
78.
The passive behavior of ZrNi alloys near the rest potential is studied through in situ voltammetry, ellipsometry, and microscopic observation. A significant oxide layer growth is observed in aqueous 1 M KOH during the application of different potential programs currently used in the activation processes of the alloy. Oxide barrier effects and occlusion of hydrogen species within the film take place. The kinetics of the oxide layer formation under potential cycling plays a significant role in the activation process of metal alloys used in metal hydride batteries.Dedicated to Professor Gyorgy Horanyi on the occasion of his 70th birthday. 相似文献
79.
Bin HU Kun XIAO Jing Kang SHEN State Key Laboratory of Drug Research Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 《中国化学快报》2006,(9)
N-Boc-α-aminoaldehydes, represented by Boc-L-leucinal and its congener Boc-L- phenylalaninal, have received considerable attention in the past four decades1. This interest mainly stems from their wide application as important synthons in the preparation … 相似文献
80.
根据GaN氢化物气相外延生长(HVPE)的原理,设计制作了双温区卧式HVPE系统.根据实际生长中出现的问题和CaN样品的测试情况,对系统进行了逐步的调试和改进. 相似文献