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461.
A. V. Gul’kin D. V. Postnikov 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2008,2(2):277-281
Radiation damage of a beryllium surface by a high-current electron beam at the GSEP-3 accelerator is considered. The degree of damage of beryllium samples has been determined. The temperature fields inside the sample and the distributions of thermal stresses have been calculated. The reasons for beryllium surface cracking formation have been found. The concentrations of point defects have been calculated. The possible reasons for an increase in microhardness of the irradiated beryllium surface layer are discussed. 相似文献
462.
A comprehensive theory of electron spin resonance (ESR) for a Luttinger liquid state of correlated metals is presented. The ESR measurables such as the signal intensity and the linewidth are calculated in the framework of Luttinger liquid theory with broken spin rotational symmetry as a function of magnetic field and temperature. We obtain a significant temperature dependent homogeneous line broadening which is related to the spin-symmetry breaking and the electron-electron interaction. The result crosses over smoothly to the ESR of itinerant electrons in the noninteracting limit. These findings explain the absence of the long-sought ESR signal of itinerant electrons in single-wall carbon nanotubes when considering realistic experimental conditions. 相似文献
463.
In this communication, we investigated the scintillation properties of Cs2LiGdCl6:10% Ce3+ single crystal. This scintillation crystal is grown by using the vertical Bridgman technique. X-rays induced emission spectra show that, Cs2LiGdCl6:10% Ce3+ emits into the Ce3+ band, spanning from 365 nm to 450 nm wavelengths. Under γ-ray excitation, the sample crystal shows three main decay time components of 129 ns (51%), 573 ns (32%) and 8.9 μs (17%). It offers an energy resolution of 5.0% (FWHM) for the 662 keV full absorption peak at room temperature. We measured an absolute light yield of 20,000 photons/MeV of absorbed γ-ray energy. We found that with a little exposure to the air, the scintillation properties of the Cs2LiGdCl6:10% Ce3+ crystal deteriorate, which is attributed to the highly hygroscopic nature of this material. We believe that the Cs2LiGdCl6:10% Ce3+ crystal can be a promising material for medical imaging and radiation detection. Moreover due to the presence of Li and Gd constituents, this scintillation crystal can also be the possible candidate for thermal neutron detection. 相似文献
464.
465.
Anwar Saeed Niqab Khan Taza Gul Wiyada Kumam Wajdi Alghamdi Poom Kumam 《Molecules (Basel, Switzerland)》2021,26(21)
This research work aims to scrutinize the mathematical model for the hybrid nanofluid flow in a converging and diverging channel. Titanium dioxide and silver are considered as solid nanoparticles while blood is considered a base solvent. The couple-stress fluid model is essentially use to describe the blood flow. Therefore, the couple-stress term was used in the recent study with the existence of a magnetic field and a Darcy–Forchheiner porous medium. The heat absorption/omission and radiation terms were also included in the energy equation for the sustainability of drug delivery. An endeavor was made to link the recent study with the applications of drug delivery. It has already been revealed by the available literature that the combination of with any other metal can destroy cancer cells more effectively than separately. Both the walls are stretchable/shrinkable, whereas flow is caused by a source or sink with α as a converging/diverging parameter. Governing equations were altered into the system of non-linear coupled equations by using the similarity variables. The homotopy analysis method (HAM) was applied to obtain the preferred solution. The influences of the modeled parameters have been calculated and displayed. The confrontation of wall shear stress and hybrid nanofluid flow increased as the couple stress parameter rose, which indicates an improvement in the stability of the base fluid (blood). The percentage (%) increase in the heat transfer rate with the variation of nanoparticle volume fraction was also calculated numerically and discussed theoretically. 相似文献
466.
467.
Dr. Seetharaman Manojveer Nitish K. Garg Zarif Gul Ayesha Kanwal Dr. Yogesh Goriya Dr. Magnus T. Johnson 《ChemistryOpen》2023,12(1):e202200245
A new class of palladium complexes bearing bidentate 2-hydroxypyridine based ligands have been prepared and fully characterized. The applications of these new complexes towards ketone alkylation reactions with alcohols through a metal-ligand cooperative borrowing-hydrogen (BH) process were demonstrated. 相似文献
468.
Mengying Zhang Ze Zhang Zarmina Gul Mengfei Tian Junling Wang Kaili Zheng Chunjian Zhao Chunying Li 《Journal of separation science》2023,46(15):2300098
In recent years, it has been found that changing ambient conditions (CO2/N2, temperature, pH) can trigger a switchable phase transition of deep eutectic solvents, and such solvents are known as responsive deep eutectic solvents. In this work, we present the development history, properties, and preparation of responsive deep eutectic solvents, followed by the application of responsive deep eutectic solvents in the extraction and separation of bioactive compounds are presented. Importantly, the mechanism of responsive deep eutectic solvents in the extraction of bioactive compounds is discussed. Finally, the challenges and prospects of responsive deep eutectic solvents in the extraction and separation of bioactive compounds are proposed. Responsive deep eutectic solvents are considered green and efficient solvents. Some methods for extraction and separation of bioactive compounds by responsive deep eutectic solvents can increase the possibility of recycling the deep eutectic solvents, and provide higher efficiency in the extraction and separation field. It is hoped that this will provide a reference for the green and sustainable extraction and separation of various bioactive compounds. 相似文献