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121.
Cui-Hua Wang Guo-Feng Li Yan Wu Yu Wang Jie Li Duan Li Ning-Hui Wang 《Plasma Chemistry and Plasma Processing》2007,27(1):65-83
Algae in drinking water supplies often bring about impact on the water treatment. In this study, a bipolar pulsed dielectric
barrier discharge system in three-phase discharge plasma reactor was constructed for investigating its ability to control
excessive growth of cyanobacteria, Microcystis aeruginosa. Experimental results show there was almost no change in optical density immediately after the interruption of electrical
discharge, but the decreasing trend of optical density, cell density and chlorophyll-a content was obvious during the incubation period, indicating a significant residual effect of electrical discharge process
on the algal growth inhibition. Scanning electron microscopy investigation of algae revealed surface damage, apparent leakage
of intracellular contents and pores formed after electrical discharge process, which showed that algal cells had no potential
to survive and grow. Compared with the control sample, it was observed that electrical discharge on the algal extracellular
products has almost no residual effect and the growth rate of algae slightly decreased before three days storage. Hydrogen
peroxide was produced by electrical discharge in the μM level and showed a first-order decay. But at such level, the external
addition of hydrogen peroxide alone is not likely to cause the residual effect. These results implicated that the growth inhibition
of M. aeruginosa was mainly caused by electrical discharge process, and it made the algal cells lose ability to survive, demonstrating the
considerable potential of such an alternative process for efficient water purification. 相似文献
122.
L. Ledernez F. Olcaytug G. A. Urban H. K. Yasuda 《Plasma Chemistry and Plasma Processing》2007,27(6):659-667
This work deals with the luminous chemical vapour deposition (plasma polymerization) of hydrocarbon polymeric thin films in
a magnetic field enhanced discharge of methane. The films were deposited on 4″ <111> single crystal silicon substrates. We
investigated the influence of the different glow discharge parameters (e.g. pressure, flow rate, power input, etc.) on the
deposition rate of methane and the refractive index of the resulting polymeric films, as well as the distribution of these
parameters across the wafer. We used a Shinko Seiki Plasma Polymerization equipment with a bell jar reactor comprising two electrodes connected to a symmetric AC power supply
of 15 kHz. Two magnetrons were formed by placing two circular shaped concentric magnetic poles behind each electrode. The
substrates were attached on both sides of a rotating wheel held at a floating potential in the middle of the two electrodes.
This equipment allowed us to vary a single parameter and keep the other parameters constant over the whole process. We measured
the thickness and the refractive index and their distribution over the wafer. The effect of the system pressure, decoupled
from the effect of flow rate, is explained by the characteristic nature of luminous gas phase and by the polymerization/deposition
mechanism of luminous chemical vapour deposition. 相似文献
123.
将射频等离子体技术应用于杂多蓝的制备中, 成功地制备出四电子还原的磷钼杂多蓝, 并对所制备的杂多蓝进行了结构表征及性质研究, 探讨了磷钼杂多酸在射频氢等离子体中的还原行为. 相似文献
124.
125.
采用熔体快淬法制备了(Mg70.6 Ni29.4)90Nd10的非晶贮氢合金带,用X射线衍射仪和高分辨电镜对该合金在充放电循环过程中的组织结构演变进行了动态跟踪.结果表明:(Mg70.6Ni29.4)90Nd10贮氢合金在充放电循环过程中由非晶态慢慢晶化为纳米晶,初生相NdMg2 Ni9在循环过程中逐渐转化为Mg2 Ni,α-Mg和Nd2H5相.电化学性能测试表明,由于微观结构的变化对其放电容量的影响过程分为3个阶段:首先是前两个循环的活化过程,在第3个循环达到放电容量最高值(580.5 mAh·g-1);接下来是放电容量显著降低的4~10个循环阶段;最后是放电容量保持稳定的11 ~20个循环.研究发现NdMg2 Ni9相的存在和保持合金的非晶结构是提高镁基电极合金循环稳定性的重要因素. 相似文献
126.
TiO2 decorated with partially crystallized Pd nanoparticles (Pd/TiO2-P) was successfully prepared by atmospheric-pressure dielectric barrier discharge cold plasma. The XRD and XPS analyses proved that Pd ions were reduced to partially crystallized metallic Pd nanoparticles in Pd/TiO2-P. The XPS spectra also indicated that an enhanced metal-support interaction was formed due to the existence of partially crystallized Pd nanoparticles with lower coordination number in Pd/TiO2-P. Photocatalytic activity of Pd/TiO2-P was much higher than that of TiO2 samples decorated with well crystallized Pd nanoparticles. 相似文献
127.
利用原位发射光谱表征和在线色谱分析,研究了甲醇介质阻挡放电脱氢偶联一步合成乙二醇反应中氢气的催化作用,考察了放电频率、甲醇和氢气进料量以及反应压力的影响.结果表明,在介质阻挡放电产生的非平衡等离子体中,H2不但能显著提高甲醇转化率,而且能显著提高乙二醇的选择性.在300°C,0.1 MPa,反应器注入功率为11 W,放电频率为12.0 k Hz,甲醇气体进料量为11.1 m L/min,氢气进料量为80–180 m L/min的条件下,甲醇转化率接近30%,乙二醇选择性大于75%.乙二醇收率与激发态氢原子的Hα谱线强度之间存在同增同减关系.由此推测,氢原子是起催化作用的活性氢物种.活性氢物种的生成途径是:基态氢分子通过与电子碰撞变成激发态,激发态氢分子通过第一激发态氢自动解离为基态氢原子.放电反应条件通过影响氢分子解离来影响氢气的催化作用.氢气在非平衡等离子体中显示的催化作用有可能为开辟新的化学合成途径提供重要机遇. 相似文献
128.
The electrodeless discharge lamp: a prospective tool for photochemistry: Part 3. The microwave photochemistry reactor 总被引:1,自引:0,他引:1
Petr Kln Milan Hjek Vladimír Církva 《Journal of photochemistry and photobiology. A, Chemistry》2001,140(3):1077-189
A simple and original microwave photochemical reactor is described in detail. It consists of an electrodeless discharge lamp placed into the reaction vessel in a modified domestic microwave oven. The microwave field generates ultraviolet radiation by the lamp at the same time when it interacts with the reaction mixture. The construction, experimental set-ups, applications, and safety precautions are discussed. 相似文献
129.
130.