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31.
目前Si基半导体由于其自身材料特性的限制,已经越来越难以满足高速发展的现代电力电子技术对半导体器件的性能要求.SiC作为新一代半导体材料具有显著的性能优势,但由于其属于典型的难加工材料,实现SiC晶圆的高质量与高效率加工成为了推动其产业化应用进程的关键.本综述在回顾近年来SiC超精密加工技术研究进展的基础上,重点介绍了一种基于等离子体氧化改性的SiC高效超精密抛光技术,分析了该技术的材料去除机理、典型装置、改性过程及抛光效果.分析结果表明,该技术具有较高的去除效率,能够获得原子级平坦表面,并且不会产生亚表面损伤.同时针对表面改性辅助抛光技术加工SiC表面过程中出现的台阶现象,探讨了该台阶结构的产生机理及调控策略.最后对等离子体辅助抛光技术的发展与挑战进行了展望. 相似文献
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James I. Paul Marc J J. Schmidt Timothy J. Abram 《Crystal Research and Technology》2016,51(7):441-445
Silicon Carbide (SiC) has been deposited onto an alumina substrate by the thermal decomposition of the gaseous precursor tetramethylsilane (TMS). A 500 W ytterbium fibre laser was used to heat the surface of an alumina substrate locally, resulting in deposition of SiC at the sample surface. The SiC deposit was analysed using energy dispersive X‐ray spectroscopy and X‐ray diffraction (XRD). The deposit was confirmed to be silicon carbide and found to be face centre cubic (FCC) crystal structure. Raman spectroscopy was used to measure the stoichiometry of the deposit which initially was found to be carbon rich. Further analysis by Raman spectroscopy suggests the deposit may be more stoichiometric following a two hour thermal treatment of the sample at 600 degrees celcius in an atmosphere of air. 相似文献
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In this work, we performed density functional calculations to examine the molecular adsorption states of thiophene on β-SiC(0 0 1)-2×1 surface. A number of possible adsorption geometries are considered into two groups as the polymeric thiophene chain and the individual molecules covalently bonded onto the surface. The results show that the polymeric chain on the surface is the less stable adsorption case and individual arch like adsorption case structure is more stable than others. In all adsorption cases, the adsorbed SiC surfaces are characterized as different semiconductors. 相似文献
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The reststrahlen region of SiC is analysed with the goal of establishing the origin of different shapes of this band, by varying the dielectric parameters involved when simulating the reststrahlen region as obtained by infrared reflectance. 相似文献
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lINTRODUCTIONSiCkilnfllrniturepossessesgoodhigh-temperaturepropertiesandsmoothness.Itishighlyresistanttowarddeforming,slaggingandthermalshock.Thefurniturecanpracticallyresultinimprovingqualityandproductionofceramicsandiswidelyusedovertheworld.However,SiChassinteringtemperatureofupto2OOO:Ct13landitisdifficulttosinterasproductbyusingcommonkilnfurnace.Toserveashigh-temperaturerefractorykilnfurniture,itmustbemixedwithabonder.Thisworkus-esfinesiliconpowderasabonder,whichisadustproducedfroms… 相似文献
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Shuang-Shuang Kong Wei-Kai Liu Xiao-Xia Yu Ya-Lin Li Liu-Zhu Yang Yun Ma Xiao-Yong Fang 《Frontiers of Physics》2023,18(4):43302
Silicon carbide nanosheets (SiCNSs) have a very broad application prospect in the field of new two-dimensional (2D) materials. In this paper, the interlayer interaction mechanism of bilayer SiCNSs (BL-SiCNSs) and its effect on optical properties are studied by first principles. Taking the charge and dipole moment of the layers as parameters, an interlayer coupling model is constructed which is more convenient to control the photoelectric properties. The results show that the stronger the interlayer coupling, the smaller the band gap of BL-SiCNSs. The interlayer coupling also changes the number of absorption peaks and causes the red or blue shift of absorption peaks. The strong interlayer coupling can produce obvious dispersion and regulate the optical transmission properties. The larger the interlayer distance, the smaller the permittivity in the vertical direction. However, the permittivity of the parallel direction is negative in the range of 150-300 nm, showing obvious metallicity. It is expected that the results will provide a meaningful theoretical basis for further study of SiCNSs optoelectronic devices. 相似文献
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Graphene is scientifically and commercially important because of its unique molecular structure which is monoatomic in thickness, rigorously two-dimensional and highly conjugated. Consequently, graphene exhibits exceptional electrical, optical, thermal and mechanical properties. Herein, we critically discuss the surface modification of graphene, the specific advantages that graphene-based materials can provide over other materials in sensor research and their related chemical and electrochemical properties. Furthermore, we describe the latest developments in the use of these materials for sensing technology, including chemical sensors and biosensors and their applications in security, environmental safety and diseases detection and diagnosis. 相似文献