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991.
Bhupendra Kumar Sharma Mamta Agarwal R.C. Chaudhary 《应用数学和力学(英文版)》2007,28(3):309-309
A theoretical analysis of three-dimensional Couette flow with radiation effect on temperature distribution has been analysed, when the injection of the fluid at the lower stationary plate is a transverse sinusoidal one and its corresponding removal by constant suction through the upper porous plate is in uniform motion. Due to this type of injection velocity, the flow becomes three-dimensional. The effect of Prandtl number, radiation parameter and injection parameter on rate of heat transfer has been examined by the help of graphs. The Prandtl number has a much greater effect on the temperature distribution than the injection or radiation parameter. 相似文献
992.
A short‐range force constant model has been applied to investigate the Raman and the infrared wavenumbers in R2BaNiO5 (R = Y, Gd) in their orthorhombic phase of space group Immm. Calculations of zone‐center phonons are made with seven stretching and four bending force constants. The force constants are evaluated by fitting nine Raman and two infrared modes. Two Raman modes are reassigned on the basis of group theoretical calculations. The calculated Raman and infrared modes show good agreement with the observed values. The infrared values are assigned for the first time in these oxides. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
993.
P. V. Zinin L. C. Ming I. Kudryashov N. Konishi S. K. Sharma 《Journal of Raman spectroscopy : JRS》2007,38(10):1362-1367
A direct transformation of the g‐BC3 phase to a new diamond‐like d‐BC3 phase was observed in a diamond‐anvil cell (DAC) at high temperature, 2033 ± 241 K, and high pressure, 50 GPa. Analysis of the peak positions of the d‐BC3, B4C, α‐boron, and the boron‐doped diamond leads to the conclusion that the positions of the peaks of the d‐BC3 are more similar to the peak pattern of the boron‐doped diamond rather than that of boron carbide, α‐boron. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
994.
Some new triphenylantimony(V) derivatives of Schiff bases having the composition have been synthesized by the equimolar reactions of Ph3SbBr2 with newly synthesized benzothiazoline ligands, (where R = C6H5(H2L1), 4‐BrC6H4(H2L2), 4‐ClC6H4(H2L3), 4‐CH3‐OC6H4(H2L4), 4‐CH3C6H4(H2L5)). The reaction proceeds with the rearrangement of benzothiazoline ring. All the derivatives have been characterized by elemental analyses, molecular weight measurements and their plausible structures have been proposed on the basis of IR and NMR (1H and 13C) spectral studies. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:70–75, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20260 相似文献
995.
The desirable weight-to-axle power ratio for agricultural tractors is determined by the necessity for the optimum utilisation of the available axle power to produce the required drawbar pull at a preselected slip. For a vehicle designed to operate in a given speed range, the weight-to-axle power ratio should be within a particular limit, so that a specific level of conversion efficiency can be maintained. In this paper attempts have been made to select suitable tyres for Indian two-wheel drive tractors operating in sandy clay loam soils on the basis of weight-to-power utiisation and maximum pull-to-optimum weight ratio at a preselected slip using the developed traction prediction equations. A comparison has also been made between the desired and actual weight on a single traction wheel and suitable tyre and tyre normally fitted in Indian two wheel drive tractors up to 35 kW. 相似文献
996.
Subhajit Laha Nimish Dwarkanath Abhishek Sharma Darsi Rambabu Sundaram Balasubramanian Tapas Kumar Maji 《Chemical science》2022,13(24):7172
Light hydrocarbon separation is considered one of the most industrially challenging and desired chemical separation processes and is highly essential in polymer and chemical industries. Among them, separating ethylene (C2H4) from C2 hydrocarbon mixtures such as ethane (C2H6), acetylene (C2H2), and other natural gas elements (CO2, CH4) is of paramount importance and poses significant difficulty. We demonstrate such separations using an Al-MOF synthesised earlier as a non-porous material, but herein endowed with hierarchical porosity created under microwave conditions in an equimolar water/ethanol solution. The material possessing a large surface area (793 m2 g−1) exhibits an excellent uptake capacity for major industrial hydrocarbons in the order of C2H2 > C2H6 > CO2 > C2H4 > CH4 under ambient conditions. It shows an outstanding dynamic breakthrough separation of ethylene (C2H4) not only for a binary mixture (C2H6/C2H4) but also for a quaternary combination (C2H4/C2H6/C2H2/CO2 and C2H4/C2H6/C2H2/CH4) of varying concentrations. The detailed separation/purification mechanism was unveiled by gas adsorption isotherms, mixed-gas adsorption calculations, selectivity estimations, advanced computer simulations such as density functional theory (DFT), grand canonical Monte Carlo (GCMC) and ab initio molecular dynamics (AIMD), and stepwise multicomponent dynamic breakthrough experiments.Industrially important C2H4 purification from multi-component hydrocarbon mixtures. 相似文献
997.
Mourad Benlamri Kyle M. Bothe Alex M. Ma Gem Shoute Amir Afshar Himani Sharma Arash Mohammadpour Manisha Gupta Kenneth C. Cadien Ying Y. Tsui Karthik Shankar Douglas W. Barlage 《固体物理学:研究快报》2014,8(10):871-875
A high effective electron mobility of 33 cm2 V–1 s–1 was achieved in solution‐processed undoped zinc oxide (ZnO) thin films. The introduction of silicon nitride (Si3N4) as growth substrate resulted in a mobility improvement by a factor of 2.5 with respect to the commonly used silicon oxide (SiO2). The solution‐processed ZnO thin films grown on Si3N4, prepared by low‐pressure chemical vapor deposition, revealed bigger grain sizes, lower strain and better crystalline quality in comparison to the films grown on thermal SiO2. These results show that the nucleation and growth mechanisms of solution‐processed films are substrate dependent and affect the final film structure accordingly. The substantial difference in electron mobilities suggests that, in addition to the grain morphology and crystalline structure effects, defect chemistry is a contributing factor that also depends on the particular substrate. In this respect, interface trap densities measured in high‐κ HfO2/ZnO MOSCAPs were about ten times lower in those fabricated on Si3N4 substrates. (© 2014 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)
998.
The optimal current difference lattice hydrodynamic model is extended to investigate the traffic flow dynamics on a unidirectional single lane gradient highway. The effect of slope on uphill/downhill highway is examined through linear stability analysis and shown that the slope significantly affects the stability region on the phase diagram.Using nonlinear stability analysis, the Burgers, Korteweg-deVries(KdV) and modified Korteweg-deVries(mKdV) equations are derived in stable, metastable and unstable region, respectively. The effect of reaction coefficient is examined and concluded that it plays an important role in suppressing the traffic jams on a gradient highway. The theoretical findings have been verified through numerical simulation which confirm that the slope on a gradient highway significantly influence the traffic dynamics and traffic jam can be suppressed efficiently by considering the optimal current difference effect in the new lattice model. 相似文献
999.
Mohammed Ahmed Shehab Nikita Sharma Andrea Valsesia Gbor Karacs Ferenc Kristly Tams Kos Anett Katalin Lesk Lilla Nnai Klara Hernadi Zoltn Nmeth 《Molecules (Basel, Switzerland)》2022,27(9)
Nowadays, the use of hybrid structures and multi-component materials is gaining ground in the fields of environmental protection, water treatment and removal of organic pollutants. This study describes promising, cheap and photoactive self-supported hybrid membranes as a possible solution for wastewater treatment applications. In the course of this research work, the photocatalytic performance of titania nanowire (TiO2 NW)-based hybrid membranes in the adsorption and degradation of methylene blue (MB) under UV irradiation was investigated. Characterization techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), X-ray powder diffractometry (XRD) were used to study the morphology and surface of the as-prepared hybrid membranes. We tested the photocatalytic efficiency of the as-prepared membranes in decomposing methylene blue (MB) under UV light irradiation. The hybrid membranes achieved the removal of MB with a degradation efficiency of 90% in 60 min. The high efficiency can be attributed to the presence of binary components in the membrane that enhanced both the adsorption capability and the photocatalytic ability of the membranes. The results obtained suggest that multicomponent hybrid membranes could be promising candidates for future photocatalysis-based water treatment technologies that also take into account the principles of circular economy. 相似文献
1000.