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121.
The harmonic vibrational force fields and the IR spectrum of XSO2NCO (X= F, C1) molecules have been studied usingab initio HF/SCF method with the 6-31G’ basis set. Theab initio harmonic force fields are scaled empirically using the scaled quantum mechanical (SQM) method of Pulay. A set of scale factors
are optimized by the least-squares fitting to the experimental frequencies of FSO2NCO and then are transferred to CISO2NCO to give ana priori prediction of its fundamental frequencies. The average deviations between the theoretical frequencies and the experimental
values for FSO2NCO and C1SO2NCO are 3 and 5 cm-1, respectively. The assignments of the fundamentals for these two molecules are also made atcording to the potential energy
distributions and theab initio IR intensities
Project supported by the National Natural Science Foundation of China (Grant No. 29673029) 相似文献
122.
Z. S. Klemenkova B. V. Lokshin L. I. Strunkina M. Kh. Minacheva 《Russian Chemical Bulletin》1994,43(9):1516-1521
Raman and IR spectra (4000-50 cm–1) of solid cyclopentadienyl zirconium and hafnium hydrides Cp2MH2, Cp2MD2, Cp2Zr(H)X, and Cp2Zr(D)X (Cp = 5-C5H5; M = Zr, Hf; X = Cl, Br) have been studied. The vibrational modes of MH groups, Cp-rings, and metal-ligand bonds are discussed and the band assignments are proposed. In the solid state, these complexes form polymers with linear hydride bridges of the M-H-M type. The force constants of the M-H and M-Cp bonds increase on going from Zr to Hf.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1604–1609, September, 1994. 相似文献
123.
A.?I.?Yusipovich S.?Yu.?VassilievEmail author 《Russian Journal of Electrochemistry》2005,41(5):510-521
Basic regularities of electrochemical processes in the gap of an ex situ scanning tunneling microscope in conditions of condensation of air moisture at the sample surface are considered on a qualitative level. A layer of condensed moisture is viewed as an electrolyte in a two-electrode cell. The depolarizers present in this layer may experience electrochemical conversions on the tip and in an area of the sample surface near the tip. As a result, the recorded “tunneling” current includes electrochemical constituents. Depending on the electrochemical processes in the gap, various dependences of the tip-sample distance on the current and applied voltage can be expected. For preliminary diagnostics of processes in the gap it is suggested to use voltage-height spectra, whose shape and characteristic heights are sensitive to the nature and location of redox active species. Experimental data for various films on conducting supports (quasi-two-dimensional adsorbed layers of hemin and peroxidase, electrodeposited nonstoichiometric tungsten oxides, doped tin dioxide, solid electrolyte with ionic conduction) are presented as an examples.__________Translated from Elektrokhimiya, Vol. 41, No. 5, 2005, pp. 583–595.Original Russian Text Copyright © 2005 by Yusipovich, Vassiliev. 相似文献
124.
A polyphosphide of the type (NaP)X 1 was obtained from red phosphorus and sodium in presence of small amounts of naphthalene in 1,2-dimethoxyethane as solvent. 1 reacts with alkyl halides in dependence on the kind of alkyl group with formation of different alkylcyclophosphanes. As definite compounds Me5P5 2 , Et5P5 3 (with not definite constitution), i-Pr4P4 4 and t-Bu4P4 5 could be isolated. 1 was identified by X-ray diffraction, 2 – 5 by means of their 1H, 13C, 31P n.m.r. and mass spectra. The molecular structure of 4 was identified by electron diffraction. 相似文献
125.
[Co(amp)2Cl2]2[ZnCl4]体系中两对称异构体的2D NMR研究 总被引:7,自引:0,他引:7
The two symmetrical isomers in [Co(amp)2Cl2]2[ZnCl4](amp=2-(Aminomethyl)pyridine) system were syn-thesized by general oxidation method and were separated by chromatography and recrystallization method. Their configurations were assigned by using 2D NMR techniques, particularly the NOESY NMR spectra. Solvent used was Me2SO-d6 with the central peak of the CD3 septet as the reference ( 13C,δ 39.37; 1H,δ 2.49 relative to SiMe4). Cation exchange media used was Dowex 50Wx 2(H+ form, 200~400mesh; Biorad). 相似文献
126.
提出一种新的目标转化因子分析,其初始向量的构造基于实际最大差异光谱,无需分离即可从红外混合体系中解析出纯组份光谱。该算法简单易懂,不必迭代,运算量小,应用于模拟及实际体系,结果令人满意。 相似文献
127.
复合Fe2O3纳米粒子的高分子微球的结构表征 总被引:6,自引:0,他引:6
近年来,复合有机、无机粒子的高分子微球及其特殊性质越来越引起人们的兴趣与关注[1].获得有机、无机复合微球的方法很多,如在无机粒子存在下的乳液或无皂乳液聚会[2,3],通过可聚合的表面活性剂在粒子表面形成胶囊化层[4]以及共沉淀法等[5].这些无机粒子包括氧化钛、氧化铁、氧化铝及氧化硅等.Haga等[6]增发现包覆在聚合物粒子中的CdS与其本体的光电性质不同;单分散的聚合物微球可以在基片上被组装成二维乃至三维有序的结构[7].这为信息存储、立体印刷等领域提供了新途径.因此,将无机粒子与聚合物复合成为功能化粒子是一项有… 相似文献
128.
用离子动能谱探讨了9个苯环上不同取代基的4-氯-4′-取代-苯丁酮EI断裂的主要途径是:分子离子先进行Mclafferty重排,而后α-断裂。将电子能量降低至20e v,对Mclafferty重排的产物离子的α-断裂反应用Hammett方程处理,得回归线性方程lgZ/Z_0=-0.37σp-0.008,线性相关系数为0.9949。由此可明显地看出质谱中单分子断裂反应的取代基效应。 相似文献
129.
130.
SAPO-5,-11和-34分子筛模板剂的脱除及其结构的热致变化 总被引:2,自引:0,他引:2
用水热法合成了SAPO-5,-11和-34硅磷酸铝类分子筛。并对经不同温度焙烧处理的样品进行表征,结果表明:分子筛中模块剂的热分解过程与其结构和孔大小有较大的关系。在SAPO-5和SAPO-34分子筛中,外部联接的T-O-T键的反对称伸缩振动峰(1240cm~(-1)-1038cm~(-1))和其对称伸缩振动(734cm~(-1)-600cm~(-1))及双环的变形振动(600-500cm~(-1))的吸收峰对样品的结晶度比较敏感。但在SAPO-11中,分子筛骨架中T-O-T反对称伸缩振动(1225cm~(-1)和1038cm~(-1))随结晶度的下降而基本保持不变,但内四面体(TO_4)的对称伸缩振动,反对称伸缩振动峰及T-O弯曲振动峰随样品焙烧温度的升高而减弱并分裂。红外吸收带向低频方向移动。SEM-EDAX结果表明:随样品焙烧温度的升高,结晶度下降,分子筛晶形变得不规则,晶面越来越粗糙,但结晶度的下降并非由于其中PO_4四面体的热分解所引起,而是由外部联结的T-O-T键的断裂,双环被破坏及骨架元素间的重排所引起。 相似文献