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991.
合成了异金属含硫化合物{[W6Ag6S24][La(Me2SO)8]2}n,并用X射线单晶衍射法测定了其结构.结果表明,该化合物属三斜晶系,P-墿空间群;晶胞参数为:a=1.577 5(3),b=1.818 7(4),c=1.952 3(4)nm,α=92.210(2)°,β=106.567(3)°,γ=92.494(2)°,Z=2,Dc=2.510 g/cm3,μ=9.081 mm-1,F(000)=3 792,R1=0.040 9,wR2=0.086 9.化合物中的阴离子[(W6Ag6S24)6-]n具有异金属螺旋链结构,所有W原子和Ag原子均与S原子形成四面体配位构型. 相似文献
992.
在水热条件下合成了一例新型的多金属氧酸盐二聚物,[Ni(enMe)2]4{[Ni(enMe)2][Ni(enMe)2(H2O)]2[Mo8ⅥV6ⅣO38(VⅤO4)]2}.8H2O(1)(enMe=1,2-丙二胺),利用元素分析、红外光谱分析、粉末X射线衍射、热重分析和单晶X射线衍射表征了其结构。结果表明,化合物(1)属于单斜晶系,P2(1)/n空间群.晶胞参数为a=1.9685(4)nm,b=1.3549(3)nm,c=2.7039(5)nm,α=90°,β=93.94(3)°,γ=90°,V=7.195(2)nm3,Z=4,Dc=2.390g/cm3,Mr=2588.4,μ=3.195mm-1,F(000)=5012,最终R1=0.0743,wR2=0.1861.与此同时,(1)是第一个具有二帽-Keggin型钼钒氧簇的二聚体,它由过渡金属部分[Ni(enMe)2(H2O)]22+连接形成{[Ni(enMe)2][Ni(enMe)2(H2O)]2[Mo8ⅥV6ⅣO38(VⅤO4)]2}8-二聚阴离子. 相似文献
993.
在室温条件下合成了含三核铁簇的硫酸盐配合物K2(H3O)3[Fe3(H2O)3O(SO4)6].6 H2O,借助IR光谱、紫外-可见吸收光谱、X射线光电子能谱(XPS)和X射线单晶衍射等测试手段对其结构进行了表征.结果表明,标题化合物属于六方晶系,P6(3)/m空间群,晶胞参数为:a=b=0.963 7(2)nm,c=1.885 1(9)nm,V=1.516 3(9)nm3,Z=2,Dc=2.316 g/cm3,GOOF=1.089,R1=0.062 8,wR2=0.165 1.其分子由1个三核铁簇阴离子[Fe3(H2O)3O(SO4)6]5-、2个K+离子、3个水合质子H3O+和6个结晶水分子组成. 相似文献
994.
采用乌尔曼缩合反应合成了新型的咔唑基树状分子;利用核磁共振谱仪(1HNMR,13CNMR)和飞行时间质谱仪(MALDI-TOF-Mass)对其进行了表征;并评价了树状分子的荧光性能和电化学性能.结果表明,所合成的咔唑基树状化合物在394nm处发蓝光,同时具有低的HOMO能级. 相似文献
995.
采用B3LYP/6-311+G**方法, 我们优化了初始构型中包含两个平面五配位碳原子(ppCs)的C2+nB10-n (n=0~10)团簇的结构并计算了它们的振动频率. 计算结果表明, C2+nB10-n (n=0~2)团簇是稳定的, 而且这三个结构中ppC—B键的Wiberg键级介于0.511~0.909之间, ppC—C键的Wiberg键级为0.2254 (n=1)和0.8586 (n=2), ppC的键级介于3.778到3.879之间, 即这三个结构中存在两个ppCs, 而且ppC遵循八隅规则; C2+nB10-n (n=3~6)团簇的最稳定结构包含一个ppC; C2+nB10-n (n>6)团簇能量最低结构中不存在ppC. 而且只有团簇C2+nB10-n (n=0~2)中没有悬键, 它们的(电子数分别为: 6, 7和8, 计算它们的NICS(0)值表明强芳香性一般位于局部的三元环中心, 表明局部离域有利于平面结构的形成. C2+nB10-n (n=0~2)团簇的第一垂直激发能分别为: 1.91, 0.56和3.12 eV. 相似文献
996.
Sun Hwa Lee Li Xu Dr. Byeong Kwon Park Yuri V. Mironov Dr. Soo Hyun Kim Young Ju Song Cheal Kim Prof. Dr. Youngmee Kim Dr. Sung‐Jin Kim Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(15):4678-4685
Two new tetranuclear chalcocyanide cluster complexes, [{Mn(saloph)H2O}4Re4Q4(CN)12]?4 CH3OH? 8 H2O (saloph=N,N′‐o‐phenylenebis(salicylidenaminato), Q=Se ( 1 ‐Se), Te ( 2 ‐Te)), have been synthesized by the diffusion of a methanolic solution of [PPh4]4[Re4Q4(CN)12] into a methanolic solution of [Mn(saloph)]+. The structure of 2 ‐Te has been determined by X‐ray crystallography. These rhenium cluster‐supported [MnIII(saloph)] complexes have been found to efficiently catalyze a wide range of olefin epoxidations under mild experimental conditions in the presence of meta‐chloroperbenzoic acid (mCPBA). Olefin epoxidation by these catalysts is proposed to involve the multiple active oxidants MnV?O, MnIV?O, and MnIII? OOC(O)R. Evidence in support of this interpretation has been derived from reactivity and Hammett studies, H218O‐exchange experiments, and the use of peroxyphenylacetic acid as a mechanistic probe. Moreover, it has been observed that the participation of MnV?O, MnIV?O, and MnIII? OOC(O)R can be controlled by changing the substrate concentration. This mechanism provides the greatest congruity with related oxidation reactions that employ certain Mn complexes as catalysts. 相似文献
997.
Franziska Gruber Martin Schulz‐Dobrick Dr. Martin Jansen Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(5):1464-1469
Crystallization of [Ag14(C?CtBu)12Cl][BF4] and different polyoxometalates in organic solvents yields a series of new intercluster compounds: [Ag14(C?CtBu)12Cl(CH3CN)]2[W6O19] ( 1 ), (nBu4N)[Ag14(C?CtBu)12Cl(CH3CN)]2[PW12O40] ( 2 ), and [Ag14(C?CtBu)12Cl]2[Ag14(C?CtBu)12Cl(CH3CN)]2[SiMo12O40] ( 3 ). Applying the same technique to a system starting from polymeric {[Ag3(C?CtBu)2][BF4]?0.6 H2O}n and the polyoxometalate (nBu4N)2[W6O19] results in the formation of [Ag14(C?CtBu)12(CH3CN)2][W6O19] ( 4 ). Here, the Ag14 cluster is generated from polymeric {[Ag3(C?CtBu)2][BF4]?0.6 H2O}n during crystallization. In a similar way, [Ag15(C?CtBu)12(CH3CN)5][PW12O40] ( 5 ) has been obtained from {[Ag3(C?CtBu)2][BF4]?0.6 H2O}n and (nBu4N)3[PW12O40]. The use of charged building blocks was intentional, because at these conditions the contribution of long‐range Coulomb interactions would benefit most from full periodicity of the intercluster compound, thus favoring formation of well‐crystalline materials. The latter has been achieved, indeed. However, as a most conspicuous feature, equally charged species aggregate, which demonstrates that the short‐range interactions between the “surfaces” of the clusters represent the more powerful structure direction forces than the long‐range Coulomb bonding. This observation is of significant importance for understanding the mechanisms underlying self‐organization of monodisperse and structurally well‐defined particles of nanometer size. 相似文献
998.
999.
Hiroyuki Suga Satoshi Higuchi Daisuke Ishimoto Yuta Hashimoto Teruko Tsuchida Toshihide Baba 《Tetrahedron》2010,66(16):3070-6287
High enantioselectivities (94-96% ee) were obtained for the inverse electron-demand 1,3-dipolar cycloadditions between cyclohexyl vinyl ether and 2-benzopyrylium-4-olate generated via Rh2(OAc)4-catalyzed decomposition of o-methoxycarbonyl-α-diazoacetophenone. The reactions were effectively catalyzed by Eu(OTf)3, Ho(OTf)3, or Gd(OTf)3 complexes (10 mol %) of chiral 2,6-bis[(4S,5S)-4,5-diphenyl-2-oxazolinyl]pyridine. The reactions with the other electron-rich dipolarophiles such as allyl alcohol, 2,3-dihydrofuran, and butyl-tert-butyldimethylsilylketene acetal showed moderate enanantioselectivities (60-73% ee). Good to high enantioselectivities (73-97% ee) were also obtained for the cycloadditions between 3-acyl-2-benzopyrylium-4-olates, generated from methyl 2-(2-diazo-1,3-dioxoalkyl)benzoates and butyl or cyclohexyl vinyl ethers, in the presence of binaphthyldiimine (BINIM)-Ni(II) complexes (10 mol %). Under similar conditions, the reaction between methyl 2-(2-diazo-1,3-dioxohexyl)benzoate and 2,3-dihydrofuran was highly endo-selective, and moderately enantioselective (70% ee). For the BINIM-Ni(II)-catalyzed reactions of cyclohexyl vinyl ether, the use of an epoxyindanone as the 3-acyl-2-benzopyrylium-4-olate precursor revealed that the chiral Lewis acid can function as a catalyst for asymmetric induction. The scope of the cyclic carbonyl ylides was extended to those generated from 1-diazo-2,5-pentanedione derivatives, which were reacted with butyl or TBS vinyl ether and catalyzed using the (4S,5S)-Pybox-4,5-Ph2-Lu(OTf)3 complex to give good levels of asymmetric inductions (75-84% ee). 相似文献
1000.
Toru Amaya 《Tetrahedron letters》2010,51(26):3376-3379
The porphyrins bearing two three-dimensionally regulated oligoaniline chains with terminal pyridyl groups were synthesized. The self-assembled branched polymer complex by introducing Zn(II) to the porphyrin was achieved in solution, which underwent dropcasting on the surface of mica to result in dome-like nanostructures. 相似文献