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991.
A. M. Flakina A. N. Chekhlov M. G. Kaplunov K. V. Van R. N. Lyubovskaya 《Russian Chemical Bulletin》2008,57(1):99-104
The new conducting radical cation salt, bis(ethylenedithio)tetrathiafulvalene cyanurate, was synthesized. This salt is an
organic metal down to 4 K. The crystal structure, conductivity, and optical properties of the salt were studied.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 96–101, January, 2008. 相似文献
992.
Kun Tang JianJun Zhang Ning Ren JunRu Zheng JingYu Liu KeZhong Wu 《中国科学:化学(英文版)》2012,55(7):1283-1293
A series of lanthanide complexes with the 3,4,5-trimethoxybenzoic acid(3,4,5-tmoba) and 1,10-phenanthroline(phen),[Ln(3,4,5-tmoba) 3 phen] 2(Ln = Pr(1),Nd(2) and Ho(3)),have been synthesized and characterized by a series of techniques including elemental analysis,IR spectra,X-ray crystallography and TG/DSC-FTIR technology.The three complexes have two kinds of coordination modes,in which the Pr 3+ and Nd 3+ cations are nine-coordinated and the Ho 3+ cation is eight-coordinated.The three-dimensional IR accumulation spectra of gaseous products for complexes 1-3 were analyzed and the gaseous products were identified by the typical IR spectra obtained from the 3D surface graphs.Meanwhile,we obtained the activation energy E of the first steps of complexes 1-3 by the integral isoconversional non-linear(NL-INT) method and discussed the non-isothermal kinetics of complexes 1-3 using the Malek method.Finally,SB(m,n) was defined as the kinetic method of the first-step thermal decomposition.The thermodynamic parameters △G≠,△H≠ and △S≠ of activation at the peak temperature were also calculated. 相似文献
993.
994.
Two new coordination polymers,[Ln(oba)(ox)0.5(H2O)2]n(Ln = Ho(1),Eu(2);H2oba = 4,4?-oxybis(benzoic acid),H2ox = oxalic acid) have been synthesized under hydrothermal conditions.According to single-crystal X-ray diffraction analyses,complex 1 crystallizes in the monoclinic system,space group P21/c with a = 13.783(2),b =10.0120(15),c = 12.1974(18) ,β = 105.217(2)°,V = 1624.2(4) 3,C15H12O9Ho,Mr = 501.18,Z = 4,Dc = 2.050 g/cm3,F(000) = 964,μ = 4.919 mm-1,λ(MoKα) = 0.71073 ?,GOOF = 1.124,the final R = 0.0239 and wR = 0.0570 for 3310 independent reflections with Rint = 0.0298.Complexes 2 and 1 are isostructural.Oba and ox ligands bridge the Ln(III) ions into 2D layers with(4,4) topology,which are further interlinked into a 3D supramolecular network by hydrogen bonds.TG curves of the two complexes are studied to examine their thermal stabilities.Additionally,complex 2 shows red fluorescence in the solid state at room temperature. 相似文献
995.
The controlled synthesis of Mg(OH)2 nanowires and microflowers composed of nanoplates was successfully achieved by a template‐free hydrothermal synthetic method. It was found that the reaction medium played a crucial role in the morphological control of the precursor nanostructures. The high polarity of water molecules favored the polar growth of the precursor, resulting in the formation of nanowires with a diameter of 80 nm, whereas a mixed water/ethanol medium with a lower degree of polarity led to the formation of microflowers. Moreover, mesoporous MgO nanostructures could be obtained by further annealing these as‐prepared precursors in air at 500 °C for 2 h. During thermal treatment, the wire‐ and flower‐like morphologies were retained. Porosity formation was due to thermal decomposition of Mg(OH)2 and release of H2O. Both the mesoporous MgO nanowires and microflowers showed superior ability of adsorbing the organic dye methyl orange, and thus they are promising candidates for polluted water treatment. 相似文献
996.
997.
采用过冷熔体定向约束生长方法生长了尺寸约为30×15×8 mm3的块状间硝基苯胺晶体,并对生长晶体的光学均匀性、光学透过率、二次谐波转换效率以及激光损伤阈值等性能进行了测试.结果表明:生长的间硝基苯胺晶体在500~1150 nm波段内的光学透过率均在92;以上;最高二次谐波转换效率达到69.6;;单点激光脉冲损伤阈值分别为19.8 GW/cm2(输入光波为1064 nm)和45.3 GW/cm2(输入光波为532 nm).采用过冷熔体定向约束生长的间硝基苯胺晶体适合用作Nd: YAG激光的二次倍频器件,也适于作500~1150 nm波段的光学调制器件. 相似文献
998.
以2-巯基乙磺酸钠为配体,2,2'-联吡啶,4,4'-联吡啶为辅助配体,与硝酸铜反应,得到一种一维链状配位聚合物 [CuL(4,4'-bipy)(2,2'-bipy)H2O]n (L=-O3S-CH2-CH2-S-S-CH2-CH2-SO-3),通过元素分析、红外光谱对其进行了表征,并用X射线衍射测定了其结构.结果表明:该配合物属于单斜晶系,P2(1)/c空间群,晶胞参数为:a=0.8385(2) nm,b=1.3764(3) nm,c=2.1719(5) nm,β = 93.391(3) °,V = 2.5023(10) nm3,Z = 4. 相似文献
999.
1000.
基于平面波展开法和薄板振动方程,计算了薄板型声子晶体的带隙和减振特性,通过与有限元软件的计算结果验证带隙计算的正确性,并进一步讨论了散射体几何形状及填充率、弹性模量比、密度比等对薄板型声子晶体带隙特性和减振的影响.结果表明正多边形散射体随边数的减小,第一带隙宽度逐渐增加,正方形散射体薄板减振效果明显.填充率对声子晶体带隙特性的影响不是线性的.随散射体基体弹性模量比数量级增大,第一带隙趋于低频,宽度降低.散射体基体弹性模量比较大时,密度比越大,第一带隙宽度越大,对应的薄板结构减振特性越好. 相似文献