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121.
122.
Critical comparison of emission spectroscopic determination of dissociation in hydrogen RF discharges 总被引:1,自引:0,他引:1
The degree of dissociation of molecular hydrogen in a RF parallel plate plasma reactor is analyzed by three dif erent emission spectroscopic methods. These schemes are based on the comparison of line intensities of atomic and molecular hydrogen and of argon which is admixed as a tracer gas (actinometry). The different schemes yield similar results in the parameter ranges where they are applicable. The basic assumptions, the available cross sections, and the conditions and limitations of applicability of the different schemes are compared and discussed. 相似文献
123.
Experimental results are presented for the electron density, bias voltage, and dark space size surrounding a 18-cm-diameter cathode situated in the centre of a 30-cm-diameter, 30-cm-long glass vacuum chamber, containing low-pressure argon. The cathode is a single aluminium plate to which can be added another plate situated at various distances from the first and electrically connected to it. The effect of the second cathode is to dramatically reduce the self-bias on the driven cathode and considerably increase the luminosity: The plasma density increases but at a significantly smaller rate. 相似文献
124.
在室温下,采用射频磁控溅射法制备了Cu/TiOx纳米晶复合薄膜.利用X射线粉末衍射(XRD)、X射线光电子能谱(XPS)对其结构进行表征,并研究了Cu/TiOx复合薄膜的UV-vis吸收谱和亲水性.结果表明,退火前后薄膜中钛元素皆以Ti3+形式存在.薄膜在可见区有吸收,吸收限为600 nm左右.Cu/TiOx复合薄膜具有良好的亲水性.这主要是由于Cu的掺杂,使得薄膜的性能的亲水性变好.
关键词:
x复合薄膜')" href="#">Cu/TiOx复合薄膜
射频磁控溅射
XPS
亲水性 相似文献
125.
126.
Magnetic bunch compressor is one of the key technologies on the path to next generation accelerator driven facilities. In this paper we report the design principles and the first experimental research of the bunch compressor developed at Chinese Academy of Engineering Physics (CAEP). The length of the bunch after compressor is found to be about 0.7 ps (rms) and the peak current exceeds 500 A when operated in the optimized condition. The sensitivity of the bunch length on the phase of the acceleration field and magnetic field of the bunch compressor was also measured and analyzed. 相似文献
127.
In this study we investigated properties of ZnO thin films deposited on both oxygen-containing substrates and a substrate without oxygen content at various O2/Ar reactant gas ratios. Deposition of ZnO on indium-tin oxide (ITO) resulted in the best crystallinity, whereas the least degree of crystallization was observed from ZnO deposited on glass. All the films were found to have compressive stress, which was relieved by annealing in O2 environment. ZnO films deposited on glass revealed p-type conductivity when prepared at O2/Ar ratio of 0.25 whereas those on SiNx yielded p-type conductivity when prepared at O2/Ar ratio of 4. In addition, shallower oxygen interstitial seemed to be found from films with better crystallinity. The largest shift in binding energy of Zn2p3/2 was observed from ZnO prepared on glass at O2/Ar ratio of 0.25, whereas that of O1s was obtained from ZnO deposited on SiNx at O2/Ar ratio of 4. A model was proposed in terms of O2 diffusion and hydrogen desorption in order to account for the observed property variations depending on substrates and O2/Ar ratios. 相似文献
128.
磁流体特性对磁流变火炮后坐阻尼器性能的影响 总被引:3,自引:0,他引:3
针对火炮后坐磁流变阻尼器的特点,以某单管25 mm火炮实验用磁流变阻尼器为研究对象,基于Herschel-Bulkley本构模型,建立了该炮磁流变后坐阻尼器的轴对称一维层流模型,获得了不同磁场作用下阻尼力随活塞速度的变化规律。运用火炮的后坐运动方程,计算了不同磁流体特性指数下,火炮的后坐位移和后坐速度。计算结果表明,磁流体特性指数的变化对磁流变后坐阻尼器的性能影响显著。 相似文献
129.
An amorphous acrylic acid (AA) polymer coating was generated on TiO2 nanoparticles through pulse radio frequency (RF) plasma polymerization. The AA plasma synthesis mechanism was studied by its optical emission spectrum. The chemical structures of AA–plasma‐polymer were carefully investigated by Fourier transform infrared spectroscopy (FTIR). The dispersion behaviors of AA‐coated and uncoated TiO2 nanoparticles in glycol solution were characterized by ultraviolet absorbency and particle size distribution measurements. The results showed that the aggregation of TiO2 nanoparticles in glycol solution was effectively lowered and the dispersion was improved a lot after AA–plasma‐polymer coating. The pulse plasma coating parameters played an important role in the dispersion enhancement of TiO2 nanoparticles. By properly regulating the pulse discharge parameters, the system could gain the highest radical–monomer reactions rate, the most compatible functional groups on the nanoparticles, and the best dispersion in the background media. 相似文献
130.
Modeling multipacting to steady state saturation is of interest in determining the performance of the micro-pulse electron gun. In this paper, a novel method is proposed to calculate the multipacting resonance param- eters for the gun. This method works well, and the 2-D simulation results suggest that steady state saturation can be achieved in the gun. After saturation the transition from two-surface multipacting to single-surface multipacting occurred, and an extensive range of electron emission time is a suggested way to avoid this kind of transition. 相似文献