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551.
552.
A. A. Sidorov I. G. Fomina A. E. Malkov A. V. Reshetnikov G. G. Aleksandrov V. M. Novotortsev S. E. Nefedov I. L. Eremenko 《Russian Chemical Bulletin》2000,49(11):1887-1890
Thermal decomposition of the tetranuclear nickel(II) complex Ni4lη2-o-(NH2)(NHPh)C6H4|2(MeCN)2(μ-OOCCMe3)4(η2-OOCCMe3)2 (I) under an inert atmosphere (o-xylene, 140 °C) was investigated. Under these conditions, the asymmetric binuclear complex Ni|η2-o-(NH2)(NHPh)C6H4‖(η1-o-(NH2))(NHPh)C6H4|(η2,η-O,O-OOCCMe3)(η2-OOCCMe3) (2) was formed at the first stage. Complex2 was converted into the symmetric dimer Ni|η1-o-(NH2)(NHPh)C6H4|(μ-OOCCMe3)4 (3) upon recrystallization from benzene. The structures of complexes2 and3 were established by X-ray diffraction analysis.
Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1915–1918, November, 2000. 相似文献
553.
二[氧合—二(4—二茂铁基苯甲酸二烷基锡(Ⅳ))]配合物?… 总被引:6,自引:0,他引:6
合成了{[(n-Bu)2Sn(4-Fc-C6H4COO)]2O}2(1)和{[n-Oct)2Sn(4-Fc-C6H4COO)]2O}2(2)(Fc=ferroenyl两组新的配合物,对其进行了元素分析,并用IR,NMR(^1H,^13C,^119Sn)进行了谱学表征,单晶X射线衍射法测定表明,配合物1的晶体属单斜晶系,P21/c空间群,晶胞参数a=1.2988(1)nm,b=2.655(1)nm, 相似文献
554.
555.
1INTRODUCTIONSinceVanNiekerkandSchoening〔1〕firstdemonstratedthebinuclearnatureofcopper(Ⅱ)acetatemonohydrate,therehasbeenconsi... 相似文献
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557.
Jason L. Kreider Warren T. Ford 《Journal of polymer science. Part A, Polymer chemistry》2001,39(6):821-832
The poly(propylene imine) dendrimers DAB‐dendr‐(NH2)8, DAB‐dendr‐(NH2)32, and DAB‐dendr‐(NH2)64 were fully converted with iodomethane to quaternary ammonium ions at both chain ends and branch points and, with less iodomethane, were partially converted to quaternary ammonium ions mainly at end groups. Amidation of the primary amine ends followed by treatment with iodomethane gave the first dendrimers with quaternary ammonium ions only at branch points. After an exchange of iodide counterions for chloride, all of the quaternary ammonium ion dendrimers slightly increased the rate of decarboxylation of 6‐nitrobenzisoxazole‐3‐carboxylate ion in an aqueous solution. Similar quaternary ammonium ion dendrimers with more hydrophobic interiors or more hydrophobic chains on the ends were much more active catalysts for the decarboxylation. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 821–832, 2001 相似文献
558.
Synthesis of Carboxylate Substituted Rhenium Gold Metallatetrahedranes Re2(AuPPh3)2(μ-PCy2)(CO)7(η1-OC(R)O) (R = H, Me, CF3, Ph, 3,4-(OMe)2C6H3) The reaction of the in situ prepared salt Li[Re2(μ-H)(μ-PCy2)(CO)7(ax-C(Ph)O)] ( 2 ) with 1,5 equivalents of monocarboxylic acid RCOOH (R = H ( 4 a ), Me ( 4 b ), CF3 ( 4 c ), Ph ( 4 d ), 3,4-(OMe)2C6H3 ( 4 e ) in tetrahydrofruan (THF) solution at 60 °C gives within 4 h under release of benzaldehyde (PhCHO) the η1-carboxylate substituted dirhenium salt Li[Re2(μ-H)(μ-PCy2)(CO)7(η1-OC(R)O)] (R = H ( 4 a ), Me ( 4 b ), CF3 ( 4 c ), Ph ( 4 d ), 3,4-(OMe)2C6H3 ( 4 e )) in almost quantitative yield. The lower the pKa value of the respective carboxylic acid the faster the reaction proceeds. It was only in the case of CF3COOH possible to prove the formation of the hydroxycarbene complex Re2(μ-H)(μ-PCy2)(CO)7(=C(Ph)OH) ( 5 ) prior to elimination of PhCHO. The new compounds 4 a–4 e were only characterized by 31P NMR and ν(CO) IR spectroscopy as they are only stable in solution. They are converted with two equivalents of BF4AuPPh3 at 0 °C in a so-called cluster expansion reaction into the heterometallic metallatetrahedrane complexes Re2(AuPPh3)2(μ-PCy2)(CO)7(η1-OC(R)O) (R = H ( 7 a ), Me ( 7 b ), CF3 ( 7 c ), Ph ( 7 d ), 3,4-(OMe)2C6H3 ( 7 e )) (yield 47–71% ). The expected precursor complexes of 7 a–7 e Li[Re2(AuPPh3)(μ-PCy2)(CO)7(η1-OC(R)O] ( 8 ) were not detected by NMR and IR spectroscopy in the course of the reaction. Their existence was retrosynthetically proved by the reaction of 7 b with an excess of the chelating base TBD (1,5,7-Triazabicyclo[4.4.0]dec-5-en) forming [(TBD)xAuPPh3][Re2(AuPPh3)(μ-PCy2)(CO)7(η1-OC(Me)O] ( 8 b ) in solution. The η1-bound carboxylate ligand in 7 a–7 e can photochemically be converted into a μ-bound ligand in Re2(AuPPh3)2(μ-PCy2)(μ-OC(R)O)(CO)6 (R = H ( 9 a ), Me ( 9 b ), CF3 ( 9 c ), Ph ( 9 d ), 3.4-(MeO)2C6H3 ( 9 e )) under release of one equivalent CO. All isolated cluster complexes were characterized and identified by the following analytical methods: elementary analysis, NMR (1H, 31P) spectroscopy, ν(CO) IR spectroscopy and in the case of 7 d and 9 b by X-ray structure analysis. 相似文献
559.
选取4,4''-联苯二甲酸(4,4''-H2BPDC)和2,6-萘二甲酸(2,6-H2NDC)分别与二氯二茂锆(Cp2ZrCl2)反应制备了2例结构新颖的锆基纳米分子胶囊[Cp3Zr3(μ3-O)(μ2-OH)3]2(BPDC)3Cl2·H2O(Zr-MC-1)和[Cp3Zr3(μ3-O)(μ2-OH)3]2(NDC)3Cl2·3H2O(Zr-MC-2)。这2个分子胶囊均由3个线性羧基配体桥联2个三核茂锆建筑单元构成。利用单晶X射线衍射、粉末X射线衍射、元素分析、红外光谱、热重分析和氮气吸附-脱附等手段对化合物进行了表征。此外,荧光光谱分析表明Zr-MC-1和Zr-MC-2分别为深蓝光和蓝光发射材料,其最大发射波长分别为404和456 nm。 相似文献
560.
以1,2,4,5-苯四甲酸(H_4BETA)与1,2,3,4-丁烷四羧酸(H_4BTCA)为有机配体,采用溶剂热法,成功合成了3个金属有机框架(Metal-Organic Frameworks,MOFs):{[Co_5(BETA)_2(OH)_2(H_2O)_2]·10H_2O}_n(1)、{[Zn_5(BETA)_2(OH)_2(H_2O)_2]·10H_2O}_n(2)和{[Mn_2(BTCA)(H_2O)_3]·H_2O}_n(3),并利用X射线单晶衍射、红外光谱(IR)、荧光光谱(PL)和热重分析(TG/DTG)等测试手段对其进行了表征。单晶结构研究表明3个MOFs均属于单斜晶系,P21/n空间群;框架1和2都是由1,2,4,5-苯四甲酸与五核的金属簇连接形成三维框架结构,沿a轴方向具有一维孔道结构,孔径大小为0.990 nm×1.307 nm;框架3是由1,2,3,4-丁烷四羧酸与Mn~(2+)连接形成4,8-c网络的三维框架结构。 相似文献