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971.
Pulipaka Ramadevi Dash Soumya R. Khanvilkar Priyanka Jana Sarmita S. Devkar Ranjitsinh V. Chakraborty Debjani 《Transition Metal Chemistry》2019,44(8):721-735
Transition Metal Chemistry - Mixed ligand Ru(II) phenanthroline complexes of the type [Ru(1,10-phen)2Flq]ClO4 (RPFlq-1-3) and “piano-stool”-type Ru(II) arene complexes... 相似文献
972.
We have systematically investigated the disorder dependence electron phonon scattering rate in three dimensional disordered V82Pd18 ? xFex alloys. A minimum in temperature dependence resistivity curve has been observed at low temperature . In the temperature range the resistivity correction follows law. The dephasing scattering time has been calculated from analysis of magnetoresistivity by weak localization theory. The electron dephasing time is dominated by electron–phonon scattering and follows anomalous temperature (T) and disorder dependence behaviour like , where is the impurity resistivity. The magnitude of the saturated dephasing scattering time at zero temperature decreases with increasing disorder of the samples. Such anomalous behaviour of dephasing scattering rate is still unresolved. 相似文献
973.
T.K. Jana 《Physics letters. A》2009,373(14):1239-1241
We obtain exact solutions of the (1+1)-dimensional Klein-Gordon equation with linear vector and scalar potentials in the presence of a minimal length. Algebraic approach to the problem has also been studied. 相似文献
974.
T.K. Jana 《Physics letters. A》2008,372(14):2368-2373
Using first and second order supersymmetry formalism we obtain a class of exactly solvable potentials subject to moving boundary condition. 相似文献
975.
976.
Reduction of sulfonamides in mineral acids was investigated using fast scan differential-pulse polarography (FSDPP). The optimal medium for sulfadimidin, sulfamethoxydin and sulfamethoxypyridazin is 0.01–0.02M HCl, while for phthalazol it is 1M HCl and the latter compound can be selectively determined in the presence of other sulfonamides. Adsorptive properties on the Hg-electrode were analytically used in the case of sulfamethoxypyridazin and phthalazol. Relative standard deviation of all determinations did not exceed 8%. 相似文献
977.
Pavla?Musilov’aEmail author Jana?Musilov’a 《Communications in Mathematical Physics》2004,249(2):319-329
The problem of finding all rth order differential invariants of immersions of manifolds with metric fields, with values in a left (G1m×G1n)-manifold is formulated. For obtaining the basis of higher order differential invariants the orbit reduction method is used. As a new result it appears that rth order differential invariants depending on an immersion f:M N of smooth manifolds M and N and metric fields on them can be factorized through metrics, curvature tensors and their covariant differentials up to the order (r–2), and covariant differentials of the tangent mapping Tf up to the order r. The concept of a covariant differential of Tf is also introduced in this paper. The obtained results are geometrically interpreted as well.This research is supported by grants GAR 201/03/0512 and MSM 143100006. 相似文献
978.
This perspective gives an overview of the action spectroscopy methods for measurements of electronic, vibrational, and rotational spectra of mass-selected ions in the gas phase. We classify and give a short overview of the existing experimental approaches in this field. There is currently a plethora of names used for, essentially, the same techniques. Hence within this overview, we scrutinized the notations and suggested terms to be generally used. The selection was either driven by making the name unique and straightforward or the term being the most broadly used one. We believe that a simplification and a unification of the notation in ion spectroscopy can make this field better accessible for experts outside the mass spectrometry community where the applications of gas-phase action ion spectroscopy can make a large impact. 相似文献
979.
Monika Bosacka Anna Błońska-Tabero Elżbieta Filipek Jana Luxova Petra Šulcová 《Journal of Thermal Analysis and Calorimetry》2017,130(1):95-101
A new dichromium(III) cobalt(II) diphosphate(V) of the formula CoCr2(P2O7)2 was detected in the Co3Cr4(PO4)6–Cr(PO3)3 system. The new compound was obtained as a result of high-temperature solid-state reactions between CoCO3, Cr2O3 and (NH4)2HPO4 as well as between Cr(PO3)3 and Co3Cr4(PO4)6. CoCr2(P2O7)2 was characterized using XRD, DTA and IR methods. Results demonstrated that CoCr2(P2O7)2 crystallizes in the triclinic system and its unit cell parameters were calculated. Its infrared spectrum was presented. CoCr2(P2O7)2 melts incongruently at 1270±10 °C with a formation of solid α-CrPO4. The compound Co3Cr4(PO4)6, component of the system under study, was obtained for the first time as a pure phase. Its thermal stability was also investigated. Co3Cr4(PO4)6 is stable in air up to 1410 ± 20 °C. 相似文献
980.
Moisture content changes during drying were investigated in the present work. Particular emphasis was placed on the initial stage of drying of saturated concrete, where moisture contents are high. For this stage of drying, experimental data are lacking, and no comprehensive theory exists to describe it. The present investigation was performed experimentally and numerically for drying of cylinders with one exposed end, made of normal weight and lightweight concrete with varying water to cement ratio (w/c). The gravimetric technique was employed to obtain the spatial distribution of moisture content. The experimental results obtained indicate that drying of concrete becomes diffusion controlled when the average moisture content decreases below 70 to 80% of the initial saturation. Typical drying rates are in the order of magnitude of 0.18 kg/day/m2 and 0.02 kg/day/m2 for the first and the second stage of drying, respectively. The lightweight concrete cylinders as compared to those made of normal weight concrete exhibited higher levels of moisture content throughout the process. At high w/c ratios, the moisture profiles for both types of cylinders, as expected, show steeper changes with time. Large, constant drying rates were observed both experimentally and numerically in the beginning of the drying. The numerical model developed is based on a generalized mathematical formulation for mass and heat transfer in porous media, and its predictions are in agreement with the experimental data within the uncertainty range of the input data. 相似文献