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991.
磷钨钴和磷钨镍杂多酸化学修饰电极的研究 总被引:3,自引:0,他引:3
杂多酸由于组成和结构上的特点,在电化学和电分析化学领域有着广泛应用[1,2]。迄今为止,有关磷钨钴和磷钨镍三元杂多酸化学修饰电极还未见报道。本文按文献方法[3]合成了磷钨钴(H3PW11CoO40·xH2O)和磷钨镍(H3PW11NiO40·xH2O)杂多酸,分别以H3PW12O40·xH2O、H3PW11CoO40·xH2O和H3PW11NiO40·xH2O杂多酸(以下简写为H3PW11MO40·xH2O,其中M代表W,Co和Ni)为修饰剂,采用电化学方法在导电基体玻碳(GC)电极上制备了H3PW11MO40/GC膜修饰电极,制备过程简便、快速。对膜电极的… 相似文献
992.
993.
LinKunAN XianZhangBU HaiQiangWU XinDongGUO LinMA LianQuanGU 《中国化学快报》2003,14(6):557-560
The reaction of cryptotanshinone and tanshinone IIA with several biogenic amine metabolites involved in the pathogenic pathways of HE were investigated and eight 1,2,3,4-tetrahydrophenanthrene derivatives,2-6 and 8-10,were obtained.The probable mechanism on reaction was discussed. 相似文献
994.
[reaction: see text] The susceptibility of lysophosphatidic acid (LPA) to intramolecular acyl migration impedes the determination of specific receptor activation by the sn-1 and sn-2 LPA regioisomers. An efficient enantioselective synthesis of hydroxyethoxy (HE)-substituted analogues of sn-1-acyl and 2-acyl LPA derivatives that possess palmitoyl and oleoyl chains is described. While the palmitoyl derivatives fail to activate calcium release in cells transfected with LPA(2) or LPA(3) G-protein-coupled receptors, the LPA(3) receptor is activated by both 1-HE and 2-HE oleoyl LPA analogues with a potency 10-fold lower than that of the parent oleoyl LPA. 相似文献
995.
Peng Lian Wei‐Peng Lai Hua‐Qiang Cai Shaojun Qiu Bo‐Zhou Wang Jian Lv Yong‐Qiang Xue 《International journal of quantum chemistry》2011,111(14):3571-3577
Nitrosyl cation (NO+) generating reaction HONO + H+ → NO+ + H2O has been theoretically investigated by B3LYP and high‐electron‐correlation QCISD methods with 6‐31G (d,p) basis set. The solvent effects on the geometries, reaction path properties, energies, thermodynamic, and kinetic characters in four solvents (benzene, tetrahydrofuran, acetonitrile, and water) have been calculated using self‐consistent reaction field (SCRF) approach with the polarizable continuum model (PCM). The results show that the activation energy barriers and the relative energies of the products are decreased with increase of the polarities of the solvents, and the reaction is favored in polar solvents thermodynamically and kinetically. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 相似文献
996.
Lian P Wei H Zheng C Nie Y Bian J Bian Z Huang C 《Dalton transactions (Cambridge, England : 2003)》2011,40(20):5476-5482
Two novel iridium(III) complexes, [Ir(dfppy)(2)(pmc)] and [Ir(ppy)(2)(pmc)] (dfppy = 2-(4',6'-difluoro-phenyl)pyridine, ppy = 1-phenyl-pyridine), were designed and synthesized using 2-carboxyl-pyrimidine (Hpmc) as an ancillary ligand. Single crystals were obtained and characterized by single crystal X-ray diffraction. The tetrametallic complexes {[(C^N)(2)Ir(μ-pmc)](3)EuCl(3)} (C^N = dfppy, ppy) were synthesized using the iridium(III) complexes as "ligands". Photophysical and theoretical studies indicate that [Ir(dfppy)(2)(pmc)] is more suitable for sensitizing the emission of Eu(III) ions than [Ir(ppy)(2)(pmc)]. 相似文献
997.
Isoflavone derivatives were synthesized via intramolecular cyclization of 3‐(2‐bromophenyl)‐3‐oxopropanal derivatives, using CuI as the catalyst, 2‐picolinic acid (=pyridine‐2‐carboxylic acid) as the ligand, K2CO3 as the base, and DMF as the solvent, in up to 96% yield. The synthesis is functional group‐tolerant. 相似文献
998.
以硝基乙烷为原料, 经缩合、 氧化及酯化反应, 设计合成了含能增塑剂2,2-偕二硝基丙基三氟丙酸酯(DNPTFP); 利用核磁共振波谱、 红外光谱和元素分析对其结构进行了表征. 优化了DNPTFP的合成工艺, 确定酯化反应的较佳反应条件: 以甲苯为反应溶剂, n(2,2-偕二硝基丙醇)∶n(三氟丙酸)=1∶1.10, 催化剂浓硫酸的质量分数为5.0%, 反应温度110 ℃, 反应时间10 h. 在此条件下, DNPTFP的收率和纯度分别为75.2%和99.0%. 热分析测试结果表明, DNPTFP的玻璃化转变温度为-80.5 ℃, 热分解温度为267.59 ℃; 机械感度测试结果表明, DNPTFP的撞击感度为H50=125.9 cm, 摩擦感度为0, 说明DNPTFP具有良好的低温性能、 热稳定性及较低的机械感度. 此外, 相溶性试验、 黏度及玻璃化转变温度测试结果表明, DNPTFP与聚叠氮缩水甘油醚(GAP)相溶性良好, DNPTFP可显著调控GAP的黏度和玻璃化转变温度, 并且随其含量增加黏流活化能逐步降低, 增塑效率逐步升高. 因此, DNPTFP对GAP展现出优良的增塑效果, 在GAP基火炸药配方中有良好的应用前景. 相似文献
999.
Jingjing Yao Prof. Dr. Xiaohua Liu Peng He Yin Zhu Xiangjin Lian Dr. Lili Lin Prof. Dr. Xiaoming Feng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(48):16424-16430
Chiral N,N′‐dioxide/Zn(NTf2)2 complexes were demonstrated to be highly effective in the direct asymmetric conjugate addition of arylacetonitriles to alkylidene malonates under mild conditions. A wide range of substrates were tolerated to afford their corresponding products in moderate‐to‐good yields with high diastereoselectivities (82:18–>99:1 d.r.) and enantioselectivities (81–99 % ee). The reactions performed well, owing to the high Lewis acidity of the metal triflimidate and a ligand‐acceleration effect. The N,N′‐dioxide also benefited the deprotonation process as a Brønsted base. The catalytic reaction could be performed on the gram‐scale with retention of yield, diastereoselectivity, and enantioselectivity. The products that contained functional groups were ready for further manipulation. In addition, a possible catalytic model was proposed to explain the origin of the asymmetric induction. 相似文献
1000.
Yifen Luo Bozhou Wang Guofang Zhang Yanshui Zhou Peng Lian 《Journal of heterocyclic chemistry》2013,50(2):381-385
1,3‐Dipolar cycloaddition reaction between nitrile oxide and alkyne was used to capture 3‐amino‐4‐oxycyanofurazan (AOCF), which was considered as the key intermediate during the synthesis of 3,4‐bis(4‐aminofurazano‐3‐yl)furoxan (DATF) from 3‐amino‐4‐chloroximinofurazan. The isolated isoxazoles from the reaction afforded evidences for the existence of AOCF. The structures of the isoxazoles were characterized by IR, 1H NMR, 13C NMR, MS, and elemental analysis. In addition, single crystal X‐ray diffraction of one isoxazole was obtained. 相似文献