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261.
Lu Bin Ji Min Yu Xin Feng Tao Yao Shuiliang 《Frontiers of Environmental Science & Engineering in China》2007,1(4):477-481
Non-thermal plasma technologies have shown their promising potential specially for the low concentration of volatile organic
compound control in indoor air in recent years. But it is also high energy consuming. So, to improve the energy efficiency,
adding catalysts which enhance the plasma chemical reactions to plasma reactors may be a good selection. Therefore, in this
study the manganese dioxide assisted silent discharge plasma was developed for benzene conversion at a relatively high energy
efficiency. The results show that MnO2 could promote complete oxidation of benzene with O2 and O3 produced in the plasma discharge zone. The energy efficiency of benzene conversion with MnO2 was two folds as much as that without catalysts. It was also found that the site of MnO2 in the reactor and the energy density had effects on benzene conversion. While the energy density was lower than 48 J/L,
benzene conversion decreased with the increase in the distance between MnO2 bed and the plasma discharge zone. Whereas when the energy density was higher than 104 J/L, benzene conversion had an optimal
value that was governed by the distance between MnO2 bed and the plasma discharge zone. The mechanism of benzene oxidation in plasma discharges and over MnO2 is discussed in detail.
__________
Translated from China Environmental Science, 2006, 26(6): 703–707 [译自: 中国环境科学] 相似文献
262.
263.
水中氨氮、亚硝酸盐氮及硝酸盐氮相互关系探讨 总被引:5,自引:0,他引:5
在水中,氮既是生命元素,又是环境污染的主要因子,其转化是多变的,其中硝化作用和反硝化作用是关键反应,它将较稳定的 NH4^+转化成 NO3^-,后者容易渗滤,被植物吸收或进一步脱氮。用河水进行了实验室试验,研究了氨氮、亚硝酸盐氮及硝酸盐氮三者的相互关系。观察了亚硝化作用和硝化作用的历程,描述了其变化规律,并对其在水中的迁移、转化过程及机理结合文献进行了研究讨论。根据实验结果,对今后的研究方向和污水的排放标准提出了建议。 相似文献
264.
针对在固定源排气监测中普遍存在的排放浓度折算错误问题,根据国家有关标准对各种锅炉和炉窑的适用范围和折算值进行了分类划分,以供方便查用。 相似文献
265.
郭宏飞 《湖南环境生物职业技术学院学报》2005,11(3):204-205,208
通过对郴州市实施退耕还林几年来的实践和探索,分析现状,总结经验,提出了保证工程顺利实施的建议. 相似文献
266.
张茂美 《湖南环境生物职业技术学院学报》2006,12(2):145-148
概述了近年来我国农用稀土光转换材料的研究进展及目前存在的问题.重点介绍了转光剂的类型及研究现状,展望了稀土光转换材料的发展前景. 相似文献
267.
Anne Cristina de la Vega-Leinert 《Journal of Land Use Science》2020,15(2-3):172-202
ABSTRACT The Santa Cruz lowlands, east Bolivia, are one of South America’s most dynamic agricultural frontiers. In the Chiquitania, bordering Brazil, San Ignacio de Velasco was in 2017 ranked first nationally in terms of deforestation. There, two deforestation fronts meet with mechanized agriculture expanding from the West and South and cattle ranching from the East. Chiquitano communities are demographically dominant locally but often face land scarcity. Because of their comparatively low impact on forest vegetation, they are not well represented in broad-scale quantitative Land Use/Land Cover (LULC) studies. Based on an empirical, human geographical approach, this paper investigates the transformation of the local indigenous productive matrix, the associated land-use patterns and potential socio-ecological implications. The overall aim is to bear witness to the rapid and profound reconfiguration of traditional livelihoods with their integration in the market economy and to highlight the significance of micro-scale LULC-processes at global scale. 相似文献
268.
区域土地利用类型的胁迫转换与优化配置——以三峡库区为例 总被引:30,自引:1,他引:30
三峡大坝蓄水淹没土地、库区移民安置和新城及工矿迁建等带来了库区土地利用结构与布局的巨大变化。为此,如何构建符合景观生态学原理和可持续发展准则的宏观土地利用类型新格局,不仅是近10年内百万移民安置和生产布局的重点,而且关系到库区未来经济、社会与资源、环境的协调和可持续发展。论文分析了在土地淹没与置换的胁迫条件下,库区土地资源类型转换的方式与过程;从要素控制、地段设计到系统模式优化的不同层次,提出了库区土地生态设计模式与措施;并从产业协调发展的角度,提出了库区土地利用优化配置的方案。 相似文献
269.
文章概述了洁净煤技术的定义和基本内容,评述了煤炭开发中煤层气和煤矸石污染控制、煤炭物理加工、煤炭化学转化等洁净煤技术主要领域的研究开发现状,提出了发展中国洁净煤技术的建议。 相似文献
270.
California’s population increased 25% between 1980 and 1990, resulting in rapid and extensive urbanization. Of a total 123,000
ha urbanized in 42 of the state’s 58 counties between 1984 and 1990, an estimated 13% occurred on irrigated prime farmland,
and 48% on wildlands or fallow marginal farmlands. Sixty-six percent of all new irrigated farmland put into production between
1984 and 1990 was of lesser quality than the prime farmland taken out of production by urbanization. Factors dictating the
agricultural development of marginal farmlands include the availability and price of water and land, agricultural commodity
prices, and technical innovations such as drip irrigation systems that impact the feasibility and costs of production. The
increasing amount of marginal farmland being put into production could have significant water quality consequences because
marginal lands are generally steeper, have more erodible soils, poorer drainage, and require more fertilizer than prime farmlands.
Although no data exist to test our hypothesis, and numerous variables preclude definitive predictions, the evidence suggests
that new irrigated marginal lands can increase nonpoint source (NPS) pollution for a given size area by an order of magnitude
in some cases. 相似文献