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981.
Feng W Li B Liu J Chai Z Zhang P Gao Y Zhao J 《Analytical and bioanalytical chemistry》2003,375(3):363-368
Ten male Wistar rats were intravenously injected with a single approximately physiological dose of enriched stable isotopic Cr-50 tracer solution (200 ng (50)Cr(3+)/100 g body wt). The fundamental distribution patterns of the chromium-containing proteins in the nucleic, mitochondrial, lysosomal, microsomal, and cytosolic subcellular fractions of the rat liver were investigated by means of Sephadex G-100 gel chromatography combined with neutron activation analysis via (50)Cr (n, gamma) (51)Cr reaction. In total, nine kinds of Cr-containing proteins were found in the five subcellular fractions, whose relative molecular masses were 96.6+/-6.2, 68.2+/-1.4, 57.9+/-4.7, 36.6+/-1.2, 24.2+/-1.8, 14.0+/-1.5, 8.8+/-0.6, 6.9+/-0.4, and 4.2+/-0.4 kDa. Approximately 64.5% of Cr proteins accumulated in the cytosolic fraction. The second enriched part was the nucleic fraction; about 12.2% Cr proteins were stored in this section. The 4.2-kDa molecular mass might contain the so-called low molecular weight chromium-containing substance; however, in this research, it was only observed in the mitochondria, lysosome, and microsome. In the mitochondrial fraction, most of the Cr proteins were present as relatively low molecular weight substances: about 56% of chromium-containing proteins had molecular masses < or =6.9 kDa. Nevertheless, more than 69% of Cr-containing proteins were observed with molecular masses > or =57.9 kDa in the liver cytosolic fraction. 相似文献
982.
2,6-二乙酰吡啶类双希夫碱配合物的研究——Ⅰ.VO(Ⅱ)、Mn(Ⅱ)、Fe(Ⅱ)和Fe(Ⅲ)配合物的合成和表征 总被引:3,自引:1,他引:3
制备了由2,6-二乙酰吡啶与肼基硫代甲酯衍生的希夫碱C5H3N[CH=NN=C(S)XR]2(X=S,R=CH3,C6H5CH2;X=O,R=C6H5CH2)。离析出类型为MC5H3N[CH=NN=C(S)XR]2(M=VO2+、Mn2+和Fe2+)和FeC5H3N[CH=NN=C(S)SR]2Cl的希夫碱配合物。希夫碱及其配合物为元素分析、红外、可见一紫外光谱以及磁化率测量所表征,结果与所提出的Mn2+、Fe2+及Fe3+配合物的结构一致.在VO(Ⅱ)配合物的情况,则形成多聚体,其结构为: -(N3S2)V-O-V(N3S2)-O-V(N3S2)-. 相似文献
983.
Using polyvinylpyrrolidone (PVP) as a stabilizing agent, stable colloidal solutions of platinum nanoparticles of different size distributions have been prepared by reducing H2PtCl6 with hydrogen. The UV-vis adsorption peaks at 258 nm due to the adsorption of Pt(IV) species disappear completely, indicating that the Pt(IV) species has been used up and colloidal Pt has been formed. The electrodes have been prepared from aqueous Pt colloids and glassy carbon (GC). The effect of platinum particle size of Pt/GC catalyst electrode on the electrocatalytic oxidation of carbon monoxide has been investigated. The voltammetry shows that a higher potential is needed for the oxidation of absorbed carbon monoxide with a decrease of the platinum particle size for particle sizes larger than 1 nm. But for particle sizes smaller than 1 nm, the potential remains constant while the activity decreases with decreasing the size. The snowlike, well-dispersed, and highly ordered platinum nanoparticles demonstrate high activity in the oxidation reaction of carbon monoxide. The reason may be due to the geometric structure of platinum nanoparticles. 相似文献
984.
Hong Dong DUAN Wan Guo HOU* De Jun SUN Bo Geng LI Institute of Polymer Science Engineering Department of Chemical Engineering Zhejiang University Hangzhou Key Laboratory for Colloid Interface Chemistry of Education Ministry 《中国化学快报》2002,13(6)
Aqueous gels formed by the crosslinkage of Cr(III) with partially hydrolyzed polyacrylamide (HPAM), have been commonly applied in the field of petroleum production1. Polymer and surfactants are used in enhancement of oil recovery2. Some studies3 indicate that a strong interaction is existent between polyeletrolytes and oppositely charged surfactants. So it is very important to study the effect of cationic surfactants on the gelation process of crosslinkage of Cr(III) with HPAM. To o… 相似文献
985.
Mancheng Hu Chunyu Geng Zhihong Liu Yucheng Jiang Shuni Li 《Thermochimica Acta》2005,430(1-2):197-199
New compounds of phthalic acid, Cs(HPHT), and terephthalic acid, Cs2(TPA), have been synthesized. The enthalpy of solution of Cs(HPHT) in water was determined and combined with the standard molar enthalpies of formation of CsOH(aq), H2O(l) and phthalic acid(s) to calculate the standard molar enthalpy of formation of Cs(HPHT) of −(1035.6 ± 0.5) kJ mol−1. The enthalpies of solution of Cs2(TPA) and TPA in approximately 0.11 mol dm−3 CsOH were determined and combined with the standard molar enthalpies of formation of TPA(s), H2O(l) and CsOH(aq, 1:500) to calculate the standard molar enthalpy of formation of Cs2(TPA) of −(1266.2 ± 0.3) kJ mol−1. 相似文献
986.
制备了由2,6—二乙酰吡啶和肼基硫代甲酸酯衍生的希夫碱C_5H_3N[CH=NNHC(S)XR]_2(X=S,R=CH_3、C_6H_5CH_2;X=O,R=C_6H_5CH_2).离析出类型为MC_5H_3N[CH=NN=C(S)XR]_2(M=Co~(2+)、Ni~(2+)、Zn~(2+)、Pb~(2+)和Cd~(2+))的希夫碱配合物.配合物为元素分析、红外、可见—紫外光谱以及磁化率测量所表征.结果指出:上述希夫碱均为N_3S_2型五齿配体. 相似文献
987.
Peter A. Gordon Martin Schiller Chien-Ping Chai Kao Scott Bair Daniel G. Friend 《Fluid Phase Equilibria》2007,260(2):164-168
We outline the procedures used to establish benchmark physical property data for the Third Industrial Fluid Properties Simulation Challenge. For both challenge problems, this involved measurement of new data, including bubble-point pressures of ethanol/HFC-227ea mixtures at 343.13 K, and the viscosity of 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2-methyl-1,3-propanediol, and 1,2,4-butanetriol at 373 K and 0.1 and 250 MPa. When possible, measurements were compared with published literature data. Recommended values are provided with corresponding uncertainty estimates. 相似文献
988.
989.
The maximum of the color-conferring charge-transfer (CT) band in Prussian Blue (PB) varies with the electrochemically introduced cation M(z+) incorporated (as "supernumerary") for charge neutrality, and the dependence on particular properties of the M(z+) has been sought. With alkali-metal ions, the CT-maximum shifts are in the same sequence as the PB mass changes on M+ insertion; the effect on the CT ground state of the intra-lattice interaction of an M+ with the ferrocyanide CN- moiety (competing with cation hydration), is then implicated in shifts of the maxima, as the ferrocyanide is the donor center in the optical CT. More definitely, for M2+ and Ag+, solubility-products of the insoluble M(z+) ferrocyanides (that provide direct indicators of the intra-lattice M(z+)-[Fe(II)(CN)(6)](4- interactions) show a strong correlation with the spectral shifts. The determining interaction of M(z+) with ferrocyanide within PB is enhanced in some cases by the accessibility of M(z+) oxidation states +/- 1 different from the common values. PB lattice energies and the ground states of the optical CTs thus appear closely interlinked. The electrochemical uptake of appreciable amounts of the M(z+) within the lattices was confirmed by XPS. 相似文献
990.