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101.
GuoDong Tan 《Thin solid films》2010,518(13):3541-3545
Arc-vaporization is one of the common methods to synthesize single-walled carbon nanotubes (SWNTs). However the detailed synthesis mechanism is still not clear, and the synthesis of longer and chirality-selected SWNTs has not been obtained. Here influence of the gravity G = 1 g0, 2 g0, and 3 g0 is studied in order to develop the synthesis method of SWNTs. Simultaneously, calculations of heat convection are also carried out by using a fluid simulation program and the results are compared with the experimental results.  相似文献   
102.
Low energy arc discharge characteristics was analyzed based on dynamic V-A characteristics model. It draws conclusions that discharge time relates to the source voltage and the product of inductance and stable current, discharge time will increase when the source voltage increases; current reduce rate is in inverse proportion to the value of inductance; arc resistance when the arc occurs is the ratio of minimum arcing voltage to stable current. It also gains the expressions of arc resistance and arc power, arc resistance and arc power both increase as the source voltage increases and decrease as the value of inductance increases. Conclusions above mentioned are helpful to design intrinsically safe circuits.  相似文献   
103.
用于火焰探测的紫外光敏管   总被引:5,自引:0,他引:5  
介绍了用火焰探测紫外光敏管的结构,工作原理和主要技术参数,讨论了紫外光敏管材料及管内工作气氛的选择原则,并对影响紫外光敏管性能参数因素作了讨论。  相似文献   
104.
介绍了利用遗传算法优化隧洞开挖爆破参数的理论和方法。以及该算法在阿荣旗-深圳高速公路隧洞爆破开挖工程中的应用。实例表明,利用遗传算法来调整爆破参数和支护参数,可以有效地降低隧道爆破成本。  相似文献   
105.
In this study, the improvement in the removal of chlorobenzene (C6H5Cl) in the air was investigated by combining dielectric barrier discharge (DBD) driven by bipolar pulse-power with catalysts. Molecular sieve 4A (MS-4A) and MnO2/γ-Al2O3 (MnO2/ALP) as two kinds of catalysts were tested at different positions in a DBD reactor. Catalysts were located either in the discharging area between two electrodes, or just behind the discharging area (in the afterglow area) closed to the outlet. The results indicated that DBD reactor with a bipolar pulse power-supply produced strong instant discharge and energetic particles, which can effectively activate catalysts of MS-4A and MnO2/ALP located in the afterglow area to achieve the synergistic effects on effective fission of chemical bonds of chlorobenzene. It was considered that the gas-chlorobenzene and the chlorobenzene adsorbed on the catalysts were decomposed simultaneously.  相似文献   
106.
Temperature measurement by IR (infrared) camera was performed oll HT-T tokamak. particularly during long pulse discharges, during which the temperature of the hot spots on the belt limiter exceeded 1000℃. The heat load on the surface of the movable limiter could be obtained through ANSYS with the temperature measured by IR-camera. This work could be important for the temperature measurement and heat load study on the first wall of EAST device.  相似文献   
107.
This paper describes a novel method for the degradation of eosin by using glow discharge electrolysis (GDE). The effects of various parameters on the removal efficiency were studied. It was found that the eosin degradation could be raised considerably by increasing the applied voltage and the initial concentration, or by decreasing pH of the aqueous solution. Fe^2+ ion had an evident accelerating effect on the eosin degradation. The degradation process of eosin obeyed a pseudo-first-order reaction. The relationship between the degradation rate constant k and the reaction temperature T could be expressed by Arrhenius equation with which the apparent activation energy Ea of 14.110 kJ· mol^-1 and the pre-exponential factor k0 of 2.065× 10^-1 min^-1 were obtained, too. The determination of hydroxyl radical was carried out by using N, N-dimethyl -p-nitrosoaniline (RNO) as a scavenger. The results showed that the hydroxyl radical plays an important role in the degradation process.  相似文献   
108.
An analysis has been made on the discharge plasma coupled with an adsorbent system for NOx removal. The cascaded plasma-adsorbent system may be perceived as a better alternative for the existing adsorbent-based abatement system in the industry. In this study the exhaust is sourced from a diesel generator set. It was observed that better NO removal in a plasma reactor can be made possible by achieving higher average fields and subsequent NO2 removal can be improved using an adsorbent system connected in cascade with the plasma system. The paper describes various findings pertaining to these comparative analyses.  相似文献   
109.
Dielectric barrier discharge plasma in air was used to modify glass surface to induce the graft of silane onto the treated surface to increase the possibility of biomolecule immobilization. The plasma treated glass had been characterized by scanning electron microscopy (SEM), Fourier transform infrared attenuated total reflection spectroscopy, X-ray photoelectron spectroscopy (XPS) and surface water contact angle measurement. The validity of grafting silane onto glass surface was approved by the analysis of water contact angle measurement, SEM and XPS. The grafted silane content was measured by visible absorption spectroscopy using acid Orange-7. It is shown that the grafting density of silane for glass samples increases significantly after plasma treatment.  相似文献   
110.
Parametrical effect on plasma discharge and beam extraction in the diagnosis neutral beam (DNB) system for HT-7 tokamak was studied experimentally. Useful results with an improved beam quality were obtained.  相似文献   
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