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901.
The heat capacity of LuPO4 was measured in the temperature range 6.51-318.03 K. Smoothed experimental values of the heat capacity were used to calculate the entropy, enthalpy and Gibbs free energy from 0 to 320 K. Under standard conditions these thermodynamic values are: (298.15 K) = 100.0 ± 0.1 J K−1 mol−1, S0(298.15 K) = 99.74 ± 0.32 J K−1 mol−1, H0(298.15 K) − H0(0) = 16.43 ± 0.02 kJ mol−1, −[G0(298.15 K) − H0(0)]/T = 44.62 ± 0.33 J K−1 mol−1. The standard Gibbs free energy of formation of LuPO4 from elements ΔfG0(298.15 K) = −1835.4 ± 4.2 kJ mol−1 was calculated based on obtained and literature data. 相似文献
902.
Two compounds, BaNd2Fe2O7(s) and BaNdFeO4(s) in the quaternary system BaNdFeO were prepared by citrate-nitrate gel combustion route and characterized by X-ray diffraction analysis. Heat capacities of these two oxides were measured in two different temperature ranges: (i) 130-325 K and (ii) 310-845 K, using a heat flux type differential scanning calorimeter. Two different types of solid-state electrochemical cells with CaF2(s) as the solid electrolyte were employed to measure the e.m.f. as a function of temperature. The standard molar Gibbs energies of formation of these quaternary oxides were calculated as a function of temperature from the e.m.f. data. The standard molar enthalpies of formation from elements at 298.15 K, ΔfHm° (298.15 K) and the standard entropies, Sm° (298.15 K) of these oxides were calculated by the second law method. The values of ΔfHm° (298.15 K) and Sm° (298.15 K) obtained for BaNd2Fe2O7(s) are: −2756.9 kJ mol−1 and 234.0 J K−1 mol−1 whereas those for BaNdFeO4(s) are: −2061.5 kJ mol−1 and 91.6 J K−1 mol−1, respectively. 相似文献
903.
The binding of cetylpyridinum chloride (CPC) with glucose oxidase (GOD) has been extensively studied at various experimental conditions such as ionic strength, urea concentration and pH at 25 °C, using ion-selective membrane electrodes, UV–vis absorption spectroscopy and enzyme activity assay method. The accurate binding isotherms have been obtained and analyzed in terms of Scatchard plot and binding capacity concept. The results represent two binding set system for most of studied conditions. The values of Hill equation parameters have been estimated and used for calculation of intrinsic Gibbs free energy of binding. The results have been interpreted in terms of structural viewpoint of GOD and nature of interactions in the solution. The interpretations are in good agreement with denaturation experiment. Activity measurements represent the significant activation of enzyme due to binding of first CPC molecules. However, the binding of subsequent CPC diminished the activity of enzyme which may be due to the binding of second CPC to enzyme active site. The complete deactivation of enzyme is reached due to binding of about five CPC ions. 相似文献
904.
905.
906.
研究了仓库容量可以控制的、基于折扣准则的多周期随机存贮模型.利用马氏决策过程(MDP)的方法,建立了最小折现成本所满足的最优方程,在此基础上,得到了一个(Ut*,yt*(b))结构的最优策略:当仓库容量小于Ut*时将容量扩充到Ut*,并订货至Ut*;否则保持仓库容量不变,且当存贮量小于yt*(b)时订货到yt*(b),反之不订货. 相似文献
907.
Anders Björn 《Czechoslovak Mathematical Journal》2006,56(1):179-227
We develop a theory of removable singularities for the weighted Bergman space
, where μ is a Radon measure on ℂ. The set A is weakly removable for
, and strongly removable for
.
The general theory developed is in many ways similar to the theory of removable singularities for Hardy H
p
spaces, BMO and locally Lipschitz spaces of analytic functions, including the existence of counterexamples to many plausible
properties, e.g. the union of two compact removable singularities needs not be removable.
In the case when weak and strong removability are the same for all sets, in particular if μ is absolutely continuous with respect to the Lebesgue measure m, we are able to say more than in the general case. In this case we obtain a Dolzhenko type result saying that a countable
union of compact removable singularities is removable.
When dμ = wdm and w is a Muckenhoupt A
p
weight, 1 < p < ∞, the removable singularities are characterized as the null sets of the weighted Sobolev space capacity with respect to
the dual exponent p′ = p/(p − 1) and the dual weight w′ = w
1/(1 − p). 相似文献
908.
The ion-exchange electrochromatography with an oscillatory electric field perpendicular to the mobile-phase flow driven by pressure (pIEEC) was used to separate hen egg-white (HEW) proteins. The results were compared with those of normal ion-exchange chromatography (IEC). The column was designed as three-compartment rectangular column of 2-mL with dimensions (length x width x depth) of 40 x 10 x 5 mm(3) and the electric field was applied across the direction of column width. Q Sepharose FF was packed into the central compartment as the chromatographic bed. It was confirmed that the dynamic binding capacity (DBC) of different proteins (ovotransferrin and ovalbumin) in the HEW solution increased 2.3 times when an oscillatory electric current of 30 mA at 1/20 Hz was applied in the transverse column direction. Then, the HEW proteins were separated by the pIEEC at loading amounts 2.3-fold higher than those by the IEC. When the feedstock of about one-third of the DBC was applied to the columns (i.e., 7 mL for the pIEEC and 3 mL for the IEC), similar separation efficiencies of the two chromatographic modes were achieved. Both the recovery yield and purity reached 73% to over 90%. The results indicate that the pIEEC is promising for high-capacity purification of proteins. 相似文献
909.
910.