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951.
碘离子的氧化与碘单质的分离是海带中碘元素分离的关键步骤。采用反加试剂法改进碘离子氧化步骤,采用水蒸气蒸馏法改进碘单质的分离,达到了实验现象明显,终点判断简单,分离度高,环境污染少的优点。 相似文献
952.
Hsin‐Yu Huang Huey‐Min Wang Rei‐Sheu Hou Hui‐Ting Cheng Ling‐Ching Chen 《中国化学会会志》2008,55(6):1204-1207
The task‐specific ionic liquid (TSIL) and 1‐n‐butyl‐3‐methylimidazolium thiocynanate, ([bmim]SCN) were used as the medium as well as the reactant for the synthesis of α‐thiocynanatoketones by the reaction with α‐sulfonyloxy aryl ketones. Significant rate enhancements and improved yields have been observed. 相似文献
953.
Nandkishor N. Karade Sumeet V. Gampawar Jeevan M. Kondre Sandeep V. Shinde 《Tetrahedron letters》2008,49(28):4402-4404
A novel one-pot procedure for the synthesis of 3-carbomethoxy-4-aryl furan-2-(5H)-ones is reported via α-tosyloxylation of enolisable ketones with [hydroxy(tosyloxy)iodo]benzene, followed by treatment with potassium monomethyl malonate and K2CO3. 相似文献
954.
Gaojun Sun 《Tetrahedron letters》2008,49(33):4929-4932
A novel molecular iodine-catalyzed benzylation of arenes with benzyl alcohols has been developed. The reaction can be carried out under mild conditions to afford a series of diarymethane derivatives in high yields and good regioselectivities. 相似文献
955.
The substitution of hypervalently bonded fluorine atoms in C6F5IF4 was performed with C6F5BF2 and resulted in the new salt [(C6F5)2IF2][BF4]. The iodonium(V) salt was characterized by multi‐NMR and Raman spectroscopy and X‐ray crystal structure analysis. The fluorinating ability of the new electrophilic cation [(C6F5)2IF2]+ was exemplified in reactions with monovalent iodine compounds (C6F5I, p‐FC6H4I, and I2) and with electron‐poor tri(organyl)pnictanes ER3 (E = P, As, Sb, Bi; R = C6F5). In a heterogeneous reaction with CsF in MeCN the [(C6F5)2IF2]+ cation forms the dinuclear [{(C6F5)2IF2}2F]+ cation. 相似文献
956.
Catalyzed by molecular iodine at room temperature, under solvent‐free conditions, a two component aza‐Diels‐Alder cyclization of N‐vinyl‐2‐pyrrolidinone with N‐arylimine gave tetrahydroquinoline derivatives in good yields and high stereo‐selectivity. And three components aza‐Diels‐Alder reaction of N‐vinyl‐2‐pyrrolidinone, anilines and indole‐3‐carbaldehydes under the same condition afford only cis‐product in good yields. 相似文献
957.
《Angewandte Chemie (International ed. in English)》2017,56(20):5465-5470
A major challenge is the development of multifunctional metal–organic frameworks (MOFs), wherein magnetic and electronic functionality can be controlled simultaneously. Herein, we rationally construct two 3D MOFs by introducing the redox active ligand tetra(4‐pyridyl)tetrathiafulvalene (TTF(py)4) and spin‐crossover FeII centers. The materials exhibit redox activity, in addition to thermally and photo‐induced spin crossover (SCO). A crystal‐to‐crystal transformation induced by I2 doping has also been observed and the resulting intercalated structure determined. The conductivity could be significantly enhanced (up to 3 orders of magnitude) by modulating the electronic state of the framework via oxidative doping; SCO behavior was also modified and the photo‐magnetic behavior was switched off. This work provides a new strategy to tune the spin state and conductivity of framework materials through guest‐induced redox‐state switching. 相似文献
958.
Dr. Peter Becker Thomas Duhamel Christopher J. Stein Prof. Dr. Markus Reiher Prof. Dr. Kilian Muñiz 《Angewandte Chemie (International ed. in English)》2017,56(27):8004-8008
An unprecedented method that makes use of the cooperative interplay between molecular iodine and photoredox catalysis has been developed for dual light-activated intramolecular benzylic C−H amination. Iodine serves as the catalyst for the formation of a new C−N bond by activating a remote C −H bond (1,5-HAT process) under visible-light irradiation while the organic photoredox catalyst TPT effects the reoxidation of the molecular iodine catalyst. To explain the compatibility of the two involved photochemical steps, the key N−I bond activation was elucidated by computational methods. The new cooperative catalysis has important implications for the combination of non-metallic main-group catalysis with photocatalysis. 相似文献
959.
沸石型金属有机框架因为其具有高孔隙率、可控的孔尺寸、规则的孔形状以及高的热稳定性和化学稳定性而被广泛研究,此类材料在碘的快速富集方面表现出潜在的应用前景。 本文通过模拟沸石的结构特点,分别利用2,5-噻吩二羧酸和4,4'-二苯醚二甲酸作为辅助配体合成两个四面体四氮唑框架(TTF-8和TTF-9)。 单晶X射线衍射测试表明TTF-8属于四方晶系,具有P42mc空间群,而TTF-9属于单斜晶系,具有P21/c空间群。 值得注意的是尽管TTF-8和TTF-9具有相同的BCT拓扑类型,但是其框架和孔道结构完全不同,而且两个四面体四氮唑框架均展示了优异、快速的碘吸附性能。 相似文献
960.