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101.
102.
Ultra-thin titanium and titanium nitride films on silicon substrate were obtained by ion beam sputtering of titanium target in vacuum and nitrogen atmosphere, using argon ions with energy of 5 keV and 15 μA target current. Elemental composition and chemical state of obtained films were investigated by X-ray photoelectron spectroscopy with using Mg-Kα X-ray radiation (photon energy 1253.6 eV). It was shown that it is possible to form both ultra-thin titanium films (sputtering in vacuum) and ultra-thin titanium nitride films (sputtering in nitrogen atmosphere) in the same temperature conditions. Photoelectron spectra of samples surface, obtained in different steps of films synthesis, detailed spectra of photoelectron emission from Si 2p, Ti 2p, N 1s core levels and also X-ray photoelectron spectra of Auger electrons emission are presented. 相似文献
103.
Excitation functions for the reaction181Ta (α,xn)185−x
Re,107,109Ag (α, ypxn) and59Co (α, ypxn) were obtained from measurements of residual activity of stacked foils from threshold to 60 MeV. The excitation functions
for the production of181Re,182Re,183Re,184Re,105Ag,111In,54Mn,56Co,58Co, and60Co, are being presented. The experimental data are compared with calculations considering equilibrium as well as pre-equilibrium
reactions according to the hybrid model of Blann. High energy part of the excitation functions is dominated by the pre-equilibrium
reaction mechanism. Calculations were done using a priori calculational method of Overlaid Alice Code of Blann. Most of the
excitation functions in the energy range mentioned above could be very well fitted with the hybrid model calculation for exciton
numbern=4 withn
p=2 andn
n=2. The overall agreement with theory is good. Certain discrepancies, however, indicate the necessity to revise the hybrid
model with respect to emission of complex particles. 相似文献
104.
105.
本文叙述了新研制的用于测量大面积相对论性电子束流强的方形罗可夫斯基线圈、薄膜回流器及法拉第筒等三种装置的结构、特性及试验结果。 相似文献
106.
Roland Bonnet 《Interface Science》1997,4(3-4):169-179
Elastic fields of translation and misfit dislocations (resp. TD's and MD's) are investigated for two types of inhomogeneous materials.First, a multilayer formed by parallel heterointerfaces or free surfaces and containing one periodic array of interfacial MD's. In the more simple case of a thin layer on a substrate, analytic solutions can be found for the displacement field u relative to a single or a hexagonal periodic array of MD's. In the less simple case of a thin bicrystal and a layer sandwiched between two semi-infinite media, explicit solutions can still be extracted. For the general case of a multilayer material which involves a number N>2 heterointerfaces, analytic expressions become intractable. Solutions can nevertheless be obtained from the numerical inversion of linear equations which express the limiting boundary conditions along the heterointerfaces.Second, a thin bicrystal containing an heterointerface perpendicular to the two free surfaces of a foil. Starting from the elastic field of an edge TD parallel to the free surfaces, it is shown how to derive that of (i) a coherent heterointerface, (ii) a semicoherent heterointerface containing a single MD, and (iii) two close and parallel coherent heterointerfaces. Numerical calculations and graphs illustrate the solutions for metals (Al, Al2Cu), semiconductor materials (CoSi2, Si, GaAs), thin foils of the GaAs/Si type and a / superalloy. 相似文献
107.
108.
The practical importance of alloy surfaces in catalysis, corrosion andother aspects of materials performance is widely recognized. What is needed now is sufficient knowledge of the relationship between externally controllable factors — alloy composition, temperature, environment — and surface properties — composition, structure, chemical activity — to control materials performance in these applications. Our purpose here is to review progress in determining and predicting the relationship between one surface property, composition, and certain externally controllable variables: overall composition, temperature, environment and physical form.We find that theoretical treatments of metal alloy surface composition now include essentially all significant physical effects and can predict values for most parameters of interest. Though improvements are still possible, the accuracy of predictions is more often limited by uncertainties or absence of the basic data for the calculations (e.g., thermochemical values) than by the models themselves.Alloy surface composition can now be measured well. The first monolayercomposition of large alloy slabs can be determined quantitatively over a wide temperature range in ultra-high vacuum. Difficulties with specimens of practical interest still challenge experimentalists. Among these are supported catalysts, surfaces under chemisorbed layers and composition of layers below the first. Significant progress is being made and we expect the next few years will see success. 相似文献
109.
Yves Fleming Tom WirtzUrs Gysin Thilo GlatzelUrs Wegmann Ernst MeyerUrs Maier Jörg Rychen 《Applied Surface Science》2011,258(4):1322-1327
With the breakthroughs in lateral resolution with regards to secondary ion mass spectroscopy in recent years, new areas of research with much promise have opened up to the scientific community. Even though the much improved lateral resolution of 50 nm can effectively deliver more accurate 3D-images, the traditional 3D reconstructions, consisting of compiling previously acquired successive secondary ion mass spectrometry images into a 3D-stack, do not represent the real localized chemical distribution of the sputtered volume. Based on samples initially analyzed on the Cameca NanoSIMS 50 instrument, this paper portrays the advantages of combining the topographical information from atomic force microscopy and the chemical information from secondary ion mass spectrometry. Taking account of the roughness evolution within the analyzed zone, 3D reconstructions become a lot more accurate and allow an easier interpretation of results. On the basis of an Al/Cu sample, a comparison between traditional 3D imaging and corrected 3D reconstructions is given and the advantages of the newly developed 3D imaging method are explained. 相似文献
110.
挠性PCB用基板材料的新发展(5)——FPC用电解铜箔的新成果 总被引:2,自引:0,他引:2
主要阐述FPC用挠性覆铜板2003年 ̄2004年在生产厂家方面及在所用材料(包括PI薄膜、铜箔)、新技术、新产品方面的新发展。 相似文献