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31.
In this paper we give a set of analytical formulae to describe the characteristics of photocathode rf guns at any rf frequencies, such as energy, energy spread, bunch length, out going current, and emittance etc. as functions of the laser injection phase, which are useful in the design and practical operation of rf guns. 相似文献
32.
GAO Jie 《中国物理C(英文版)》2009,33(4):306-310
In this paper we give a set of analytical formulae to describe the characteristics of photocathode rf guns at any rf frequencies, such as energy, energy spread, bunch length, out going current, and emittance etc.as functions of the laser injection phase, which are useful in the design and practical operation of rf guns. 相似文献
33.
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35.
The fabrication and characterization of ZnO UV detector 总被引:9,自引:0,他引:9
Tae-Hyoung Moon Min-Chang Jeong Woong Lee Jae-Min Myoung 《Applied Surface Science》2005,240(1-4):280-285
ZnO films were deposited on GaAs substrates by radio frequency (rf) magnetron sputtering followed by an ambient-controlled heat treatment process for arsenic doping. In Hall measurements, the As-doped ZnO films showed the characteristics of p-type semiconductor. The ZnO thin film p–n homojuctions were then fabricated to investigate the electrical properties of the films. The p–n homojunctions exhibited the distinct rectifying current–voltage (I–V) characteristics. The turn-on voltage was measured to be 3.0 V under the forward bias. When ultraviolet (UV) light (λ = 325 nm) was irradiated on the p–n homojunction, photocurrent of 2 mA was detected. Based on these results, it is proposed that the p–n homojunction herein is a potential candidate for UV photodetector and optical devices. 相似文献
36.
S. Klagge 《Plasma Chemistry and Plasma Processing》1992,12(2):103-128
To consider the anisotropy of the plasma in the sheath regions, Langmuir probe characteristics are measured using a direction-resolving technique. The operation frequency, related to the neutral gas density (/p0), is chosen in such a way that the electron velocity distribution function (VDF) may be regarded as frozen and the probe diagnostic may be performed without time resolution. In order to prevent convolution of the VDF from the effect of the time-dependent plasma potential, the rf component of the probe bias voltage is compensated to a minimum. The plasma potential, the mean energy of the electrons, and the electron density, averaged over the discharge bulk, are presented as functions of the discharge current and the neutral gas pressure for the O2 gas. By means of a reactor model based on the theory of plane probes and using the plasma parameter measured, the sheath and bulk portions of the maintaining voltage are separated. In this procedure the thickness of the sheaths in front of the electrodes and the phase difference between discharge current and maintaining voltage are also obtained. 相似文献
37.
Rakesh Kar 《Journal of magnetism and magnetic materials》2010,322(6):671-674
If one applies an rf magnetic field parallel to a strong static field, temperature of a ferromagnetic substance rises due to ferromagnetic resonance. This phenomenon finds immediate application in the field of hyperthermic oncology. In this work, we have found expression for the increase in temperature when a ferromagnetic material is placed under a static and a varying magnetic field of high frequency through spin wave approach. The numerical value of this increment of local temperature has been estimated for yttrium iron garnet (YIG). We also have examined the possibility of enhancing the temperature of a ferromagnetic material only by applying a strong static field. 相似文献
38.
TiO2 thin films were deposited on ITO/Glass substrates by the rf magnetron sputtering in this study. The electrochromic properties
of TiO2 films were investigated using cyclic voltammograms (CV), which were carried out on TiO2 films immersed in an electrolyte of 1 M LiClO4 in propylene carbonate (PC). As- deposited TiO2 thin film was amorphous, while the films post-annealed at 300~600°C contained crystallized anatase and rutile. With the increase
of the annealing temperature, the surface roughness of film increased from 1.232 nm to 1.950 nm. Experimental results reveal
that the processing parameters of TiO2 thin films will influence the electrochromic properties such as transmittance, ion-storage capacity, inserted charge, optical
density change, coloration efficiency and insertion coefficient. 相似文献
39.
D. Li K. Imasaki M. Aoki S. Miyamota S. Amano T. Mochizuki M. Asakawa S. Ishii 《International Journal of Infrared and Millimeter Waves》2003,24(2):211-215
We are exploring to process nuclear waste through nuclear transmutation method with ray irradiation. The ray employed for transmutation is generated in the way of Compton backscattering. Preliminary experiment is being developed on the NewSUBARU storage ring providing an electron beam with energy of 1 GeV, and 17.6 MeV ray will be generated through a head-on collision of the electron beam and a 1.064 m laser light. ray flux about the present experiment is predicted theoretically. A planned scheme for promoting the flux is also introduced, As well as the maximum laser power available for the storage ring is discussed. 相似文献
40.
P. Buchner H. Schubert J. Uhlenbusch M. Weiss 《Plasma Chemistry and Plasma Processing》2001,21(1):1-21
The high densities and high gas temperature of rf plasmas at pressures near 1 atm are favorable for the development of plasma sources capable of evaporating solid precursors in the plasma zone. In the cooler region downstream of the plasma, the evaporated material condenses to nanoparticles and/or coatings. The complete evaporation of precursors injected into a thermal plasma depends on plasma and precursor parameters and is studied in this paper. Since many parameters contribute to the evaporation, fast experimental techniques are necessary to carry out a systematic study of the evaporation process. The monochromatic imaging technique applied in this work uses an intensified CCD camera with optical filters for the detection of characteristic plasma emission lines. The high spatial and temporal resolution of this technique results in a detailed picture of plasma emission and particle evaporation for different process parameters. These results are compared to model calculations for particle evaporation. 相似文献