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51.
酰氨基硫脲及其相关化合物通常具有广泛的生物活性 ,如抗菌[1~ 3] ,抑制神经紧张[4] ,治疗血糖过低[5] ,植物生长调节[6~ 9] 等。迄今为止 ,鲜有关于双 (1 ,4 二酰基氨基硫脲 )合成的报道。为了考查该类化合物的生物活性 ,我们设计合成了一系列双 (1 ,4 二酰基氨基硫脲 )化合物 ,以下图所示的两条合成路线合成了该类化合物 :二酰氯 (1 )、异硫腈酸酰酯 (2 )等中间体可不经进一步纯化直接用于下一步反应。所生成的产物 3a 3f、3′d 3′g经DMF H2 O EtOH重结晶 ,产率达 81 %~ 98%。在合成化合物 (1 )时 ,对于一些用SOCl2 … 相似文献
52.
53.
Isothiocyanate Complexes of Copper(II) with Square-Planar and Tetragonal-Pyramidal Coordination: Structure, Phase Transitions, and Redox-Properties In dependence on the kind and size of the counter-cations Cu2+-ions form isothiocyanate complexes with different coordination number and geometry. The structures of compounds with square-planar coordination [(NEt4)2[Cu(NCS)4] · CHCl3 (brown): Space group 14/mmm, Z = 2; a = 1204.3(2) pm, c = 1154.2(3) pm] and with tetragonal-pyramidal polyhedra [(NEt4)3[Cu(NCS)5] · SM (green, SM: unidentified solvent molecule): Space group P21/c, Z = 4; a = 1154.2(6) pm, b = 2291.6(10) pm, c = 1739.9(9) pm, ß = 95.98(5)°] are reported. The green complex transforms into a brown compound at room-temperature; the transformation is (partly) reversibly. Solutions of NCS-anions and Cu2+ are redox unstable. The structure of a resulting product: (PPh4)2[Cu2(NCS)2] [Space group C2/c, Z = 4; a = 1235.4(1) pm, b = 1347.1(2) pm, c = 2953.4(11) pm, ß = 99.36(2)°] with Cu(I) dimers and two bridging NCS- ligands is also reported. 相似文献
54.
Issa Yavari 《Tetrahedron letters》2006,47(17):2953-2956
Benzoyl isothiocyanate reacts with dialkyl acetylenedicarboxylates in the presence of triphenylphosphine in a mechanistically novel reaction to afford highly substituted dialkyl 2-(benzoylimino)-5-phenyl-4H-[1,3]dithiolo[4,5-b]pyrrole-4,6-dicarboxylates with double insertion of the isothiocyanate. The reaction proceeds via a carbon to nitrogen migration of an alkoxycarbonyl group. 相似文献
55.
制备了Pr、Yb两种希土元素异硫氰酸(?)与苄胺的固体配合物.并对其进行了组成分析、红外光谱分析、X射线衍射物相分析和热重分析.测量了298.15K时两种固体配合物RE(NCS)_3·4C_6H_5CH_2NH_2在HCl水溶液中的反应热和相应的两种希土元素异硫氰酸盐水合物RE(NCS)_3·n_1H_2O(RE为Pr时,n_1=7;RE为Yb时,n_1=6)在C_6H_5CH_2NH_2-HCl-H_2O溶液中的积分溶解热以及苄胺C_6H_5CH_2NH_2在HCl水溶液中的反应热.藉助本文所设计的热化学循环,求得了这两种配合物的标准生成焓,还计算了它们的晶格能. 相似文献
56.
本文测量了298.15K时La、Ce、Pr、Nd、Sm、Eu、Gd、Dy、Ho、Yb、Y十一种希土元素异硫氰酸盐水合物[RE(NCS)_3·nH_2O]在二甲基乙酰胺(DMA)水溶液中的积分溶解热以及相应的十一种希土元素异硫氰酸盐二甲基乙酰胺配合物[RE(NCS)_3·mDMA]在水中的积分溶解热。藉助于本文所设计的热化学循环,用本文所测得的积分溶解热数据和文献数据,求得了这十一种RE(NCS)_3·mDMA的标准生成焓,进而计算出了它们的晶格能。此外,还对Tb、Er、Tm、Lu四种RE(NCS)_3·mDMA的相应数据进行了估算。 相似文献
57.
Yan Shiping Jiang Zonghui Liao Diazheng Wang Genglin Wang Ruji Wang Honggen Yao Xinkan 《Journal of inclusion phenomena and macrocyclic chemistry》1993,15(2):159-165
Crystalline [Dy(NCS)3(dibenzo-30-crown-10)(H2O)2]·H2O·MeCN can be obtained by slowly evaporating a reaction mixture of Dy(NCS)3·nH2O with dibenzo-30-crown-10 in a solution of acetonitrile. The material crystallizes in the monoclinic space groupP21/n, the cell parameters area=11.450(5),b=23.284(4),c=18.424(6)Å, =106.28(4)°,V=4715Å3,M=968.47,D
x=1.36 g cm–1, =17.80 cm–1,F(000)=1972,Z=4.2740 independently observed [I3I] reflections were used in the final least-squares refinement leading to an agreement index ofR=0.085. The Dy(III) ion coordination geometry approximates a square antiprism, involving two water oxygens and three dibenzo-30-crown-10 oxygen atoms and three isthiocyanate nitrogens. Hydrogen bonds are formed between the two water molecules and four uncoordinated crown ether oxygen atoms.
Supplementary Data relevant to this paper have been deposited with the British Library as Supplementary Publication No. SUP 82148 (22 pp.) 相似文献
58.
J. Lipkowski D. V. Soldatov N. V. Kislykh N. V. Pervukhina Yu. A. Dyadin 《Journal of inclusion phenomena and macrocyclic chemistry》1994,17(4):305-316
A phase diagram of the [Zn(MePy)2(NCS)2]-MePy binary system has been studied by DTA and solubility methods. Two compounds melting incongruently (at 63 and 57°C) have been discovered in the system. They have been obtained as separate phases with crystals of different shape (needles and octahedra). Their composition has been determined by analytical methods and verified by X-ray structural analysis: [Zn(MePy)4(NCS)2]·0.67 MePy·xH2O, wherex depends on the synthesis conditions, and [Zn(MePy)4(NCS)2]·MePy, respectively.The preliminary X-ray study of the first compound (at –100°C) has shown it to be isostructural with the known clathrates of the common formula [M(MePy)4(NCS)2]·0.67MePy·xH2O, where M=Cu, Mn, Mg andx=0–0.33. The unit cell parameters are as follows:a=27.20(1),c=11.202(4) Å, space group
,Z=9.The X-ray study of [Zn(MePy)4(NCS)2]·MePy (at–50°C) has shown it to be analogous to the organic zeolite -phase with the guest MePy molecules located in the channels formed by molecular packing of the [Zn(MePy)4(NCS)2]host. The cell is tetragonal, the space groupI41/a,a=16.845(6),c=23.496(7) Å,V=6667(4) Å3,Z=8,D
calc=1.289 g cm–3,R=0.074. The zinc cation is surrounded by a slightly irregular octahedron of six nitrogen atoms of the MePy and NCS ligands. The crystallisation field of the host [Zn(MePy)4(NCS)2] complex in the temperature range concerned is absent in the phase diagram. It suggests contact stabilization of the [Zn(MePy)4(NCS)2] molecule by the guest in the clathrates.
Supplementary Data relevant to this paper have been deposited with the British Library at Boston Spa, Wetherby, West Yorkshire, U.K. as Supplementary Publication No. SUP 82166 (15 pages). 相似文献
59.
L. Brandsma N. A. Nedolya A. C. T. H. M. van der Kerk W. Heerma E. T. H. G. Lutz R. -J. de Lang A. V. Afonin B. A. Trofimov 《Russian Chemical Bulletin》1997,46(4):832-833
The reaction of lithiated 1,1-dimethylallene with isopropyl isothiocyanate gives 3a,4,5,5a-tetrahydro-4,4,5a-trimethyl-2-methylthio-3H-cyclobuta[b]pyrrole resulting from cyclization of the intermediate 2,7-dimethyl-4-methylthio-3-azaocta-2,4,6-triene.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 865–867, April, 1997. 相似文献
60.
Preparation and cycloaddition reaction of novel azulene-substituted N-sulfinylamines 1 and 2 are reported. The influence of the -NSO group on the UV-vis and NMR spectra of the azulene ring to which it is bonded is discussed. X-ray crystal analysis of 1 revealed the syn-configuration and the twisted structure of the N-sulfinylamine moiety. The synthetic utility of 1 and 2 have been explored by the cycloaddition reaction to afford novel azulene-substituted heterocycles under high-pressure conditions. We also described herein the synthesis and some properties of related 2-azulenylisothiocyanate. 相似文献