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991.
对清洗放电时ITER辉光放电电极采用水冷和气冷条件下的电极冷却进行了计算。当辉光放电清洗功率为9000W,冷却水的流速为4~6m.s-1,入口温度为室温25°C时,电极的温升不会超100°C。当冷却媒介为氦(He),速度为300m.s-1,入口温度为室温25°C时,最高温度不会超过200°C。计算表明,当仅仅考虑因辉光放电电功率所导致电极发热时,水冷可以满足电极辉光放电时的冷却要求。 相似文献
992.
R. Cristescu C. Cojanu S. Grigorescu F. Nastase R.J. Narayan I.N. Mihailescu 《Applied Surface Science》2007,254(4):1169-1173
We have demonstrated successful thin film growth of poly(1,3-bis-(p-carboxyphenoxy, propane)-co-(sebacic anhydride)) (20:80) by matrix-assisted pulsed laser evaporation using a KrF* excimer laser (λ = 248 nm, τ = 25 ns, ν = 10 Hz). The deposited thin films have been investigated by Fourier transform infrared spectroscopy, and atomic force microscopy. We have demonstrated that the main functional groups of poly(1,3-bis-(p-carboxyphenoxy, propane)-co-(sebacic anhydride)) (20:80) are present in the deposited film. The effect of matrix on both thin film structure and surface morphology was also examined. The goal of this work is to explore laser processing of this material to create suitable constructs for drug delivery applications. 相似文献
993.
Simulate anneal arithmetic has been used to settle the problem of time bunching on a pulsed slow-positron beam device. This paper has searched for the parameters of the device in a large scope and achieved the time resolution within 150ps at the target with accelerating voltage in a range of 0.5-30kV. 相似文献
994.
A chemical vapour deposition (CVD) diamond film detector was prepared and the main characteristics for pulsed proton detection were studied at Beijing Tandem Accelerator. The result shows that the charge collection efficiency of the detector increases with increasing electric field intensity and reaches to 9.44% at 5 V/μm with the charge collection distance of 15.9 μm. The relationship between the sensitivity of the detector and proton energy is consistent with the Monte Carlo (MC) simulation result. Its plasma time for a pulse with 4.85×10^5 protons is 1l.2ns. The dose threshold for onset of damage under 9MeV proton irradiation in the detector is about 10^13 cm^-2. All of the results show that a CVD diamond detector has fast time response and high radiation hardness, and can be used in pulsed proton detection. 相似文献
995.
Both high and low frequency relaxation oscillations have been observed in an argon capacitive discharge connected to a peripheral grounded chamber through a slot with dielectric spacers. The oscillations, observed from time-varying optical emission of the main discharge chamber, show, for example, a high frequency (46 kHz) relaxation oscillation at 100 mTorr, with an absorbed power near the peripheral breakdown, and a low frequency (2.7-3.7 Hz) oscillation, at a higher absorbed power. The high frequency oscillation is found to ignite a plasma in the slot, but usually not in the periphery. The high frequency oscillation is interpreted by using an electromagnetic model of the slot impedance, combined with the circuit analysis of the system including a matching network. The model is further developed by using a parallel connection of variable peripheral capacitance to analyse the low frequency oscillation. The results obtained from the model are in agreement with the experimental observations and indicate that a variety of behaviours are dependent on the matching conditions. 相似文献
996.
997.
低温等离子体改性聚合物膜的原理 总被引:4,自引:0,他引:4
本文对等离子体的产生和性质进行了介绍,并分类按CASING(Crosslinked Actived by Species of Inert Gases)技术,反应型等离子体和聚合型等离子体对等离子体改性聚合物的自由基反应机理进行了较为详细的论述,同时还讨论了等离子体作用导致的表面物理变化。 相似文献
998.
It is shown that theory of similarity and analysis of dimensionalities (theory of generalized variables) is applicable for a kinetic analysis of a simple electrochemical reaction described by equations of the slow discharge theory. The corresponding dimensionless complexes are derived and quantitative interrelation between them is analyzed.Translated from Elektrokhimiya, Vol. 41, No. 1, 2005, pp. 116–120.Original Russian Text Copyright © 2005 by Protsenko, Danilov. 相似文献
999.
The electrical and optical characteristics of a self-initiated, low-pressure, pulsed-periodic discharge in chlorine and in a xenon/chlorine mixture are investigated. A volume discharge not bounded by dielectric walls was triggered in a spherical anode–plane cathode system of electrodes on supply of a constant positive-polarity voltage to the anode. The discharge existed in the form of a unit domain. The spatial, spectral (in the range 150–350 nm), and time characteristics (voltage, current, and photocurrent of total radiation of plasma in the spectral range 200–700 nm) of the volume discharge are investigated. Optimization of the pressure and of the structure of the working medium is carried out to obtain the maximum brightness of UV–VUV radiation of the bands of the Cl2(D–A), Cl2
**, and XeCl(D, B–X) molecules. The results obtained are of interest for being used in a pulsed-periodic, excimer-halogen low-pressure lamp. 相似文献
1000.