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81.
Increasing attention has been paid to pyrite due to its ability to generate hydroxyl radicals in air-saturated solutions. In this study, the mineral pyrite was studied as a catalyst to activate molecular oxygen to degrade Acid Orange 7 (AO7) in aqueous solution. A complete set of control experiments were conducted to optimize the reaction conditions, including the dosage of pyrite, the AO7 concentration, as well as the initial pH value. The role of reactive oxygen species (ROS) generated by pyrite in the process was elucidated by free radical quenching reactions. Furthermore, the concentrations of Fe(II) and total Fe formed were also measured. The mechanism for the production of ROS in the pyrite/H2O/O2 system was that H2O2 was formed by hydrogen ion and superoxide anion (O2 ·?) which was produced by the reaction of pyrite activating O2 and then reacted with Fe(II) dissolved from pyrite to produce ·OH through Fenton reaction. The findings suggest that pyrite/H2O/O2 system is potentially practical in pollution treatment. Moreover, the results provide a new insight into the understanding of the mechanism for degradation of organic pollutants by pyrite.  相似文献   
82.
建立中-韩自由贸易试验区是党中央、国务院做出的重大决策,是深入贯彻党的十八大精神,在新形势下全面深化改革、扩大开放战略的重大举措。辽宁省环保产业发展起步较早,尽管近年来在全国的位次有所下滑,但在产品门类、技术、人才、关联产业以及园区化、集群化的发展模式上仍具有一定优势。面对中-韩自由贸易试验区对环境服务业战略转型的机遇和挑战,辽宁省应明确提出环保产业发展战略和目标定位,要强化政府的主导作用,加强不同环境服务分类影响研究,实施国内环境服务企业的"走出去"战略,加快环境服务业发展和战略转型的法规和政策体系建设,制定针对国内环境服务企业的扶持战略,解决战略转型的保障问题。本文以自贸区贸易效应为理论依据,根据辽宁省环保产业发展现状,探索在新时期如何利用辽宁省的区位优势不断创造市场空间,加快政府职能转变,积极推进环保产业贸易和投资便利化,强化资本、技术、人才等要素构建,加强园区建设,培育领军企业。  相似文献   
83.
Titania nanotubes are gaining prominence in photocatalysis, owing to their excellent physical and chemical properties such as high surface area, excellent photocatalytic activity, and widespread availability. They are easily produced by a simple and effective hydrothermal method under mild temperature and pressure conditions. This paper reviews and analyzes the mechanism of titania nanotube formation by hydrothermal treatment. It further examines the parameters that affect the formation of titania nanotubes, such as starting material, sonication pretreatment, hydrothermal temperature, washing process, and calcination process. Finally, the effects of the presence of dopants on the formation of titania nanotubes are analyzed.  相似文献   
84.
Liu Y  Reich PB  Li G  Sun S 《Ecology》2011,92(6):1201-1207
Phenological mismatches due to climate change may have important ecological consequences. In a three-year study, phenological shifts due to experimental warming markedly altered trophic relationships between plants and insect herbivores, causing a dramatic decline of reproductive capacity for one of the plant species. In a Tibetan meadow, the gentian (Gentiana formosa) typically flowers after the peak larva density of a noctuid moth (Melanchra pisi) that primarily feeds on a dominant forb (anemone, Anemone trullifolia var. linearis). However, artificial warming of approximately 1.5 degrees C advanced gentian flower phenology and anemone vegetative phenology by a week, but delayed moth larvae emergence by two weeks. The warming increased larval density 10-fold, but decreased anemone density by 30%. The phenological and density shifts under warmed conditions resulted in the insect larvae feeding substantially on the gentian flowers and ovules; there was approximately 100-fold more damage in warmed than in unwarmed chambers. This radically increased trophic connection reduced gentian plant reproduction and likely contributed to its reduced abundance in the warmed chambers.  相似文献   
85.
The decay of wood and other cellulosic materials by fungi cause significant economic loss. The widely used chromated copper arsenate was prohibited for the environmental impact and safety of arsenic and chromium. It was found that natural product hinokitiol (HK) had fungicidal and insecticidal activities, and its toxicity was bearable for the environment. We described the practical synthesis of HK-K salt. According to the GB/T18261-2000 and LY/T1283-1998, wood preservative performance of HK-K salt was tested. The results showed that the best inhibitory concentration of HK-K salt was 50 mg/L, for which the prevention effectiveness on mold is better, the killed value is between 0 and 1, and the corrosion-resistant for wood-rotting fungi is grade A.  相似文献   
86.
ABSTRACT

This paper presents a technique for the complete, simultaneous decomposition of CO2, SO2, and NOx, as well as the simultaneous removal of fly ash by ultra-high voltage pulse activation. Ultra-high voltage narrow pulse is used to make the gases in the reactor become active molecules, which are then dissociated into nonpoisonous gas molecules and solid particles under the control of a directional reaction model. By using a sufficient charge and a strong electric field, the fly ash can be removed. It becomes the carrier of C and S, and its efficiency is 99.5%. Owing to the action of catalyst B (using Ni as the mother's body), the activation energy of CO2, SO2, and NOx gases is reduced in great magnitude, and their removal efficiency can reach 75~90% at normal pressure and 180 °C.  相似文献   
87.
1999年我国主要气象灾害及异常气候事件   总被引:3,自引:0,他引:3  
孙冷 《灾害学》2000,15(4):61-65
1999年,我国先后出现了干旱、暴雨洪涝、台风、风雹、沙尘暴、雪灾和冻害等多种气象灾害,特别是干旱持续时间长、范围广,旱情重。除上述气象灾害外,本年度还出现了冬暖,夏凉、春寒、倒春寒、夏季高温和秋老虎等异常气候事件,本文主要是几种主要气旬灾害和异常气候事件的发生特点和影响进行了分析和评述。  相似文献   
88.
通过对胶州市东部滞洪区水质现状的调查,发现水环境污染情况较为严重.水污染的主要原因是污水直接入渠,水体自净能力差.可通过实施截污与污水收集系统建设相结合、防止污水入湖及实施东部滞洪区湖水自净建设工程等措施改善东部滞洪区的污染现状.  相似文献   
89.
中国石油天然气集团公司(CNPC)为了实现与国际石油工业管理接轨,从1994年开始按照行业标准SY/TC6276-1997《石油天然气工业健康、安全与环境管理体系》的规定,在全系统开展了建立和实施HSE管理体系工作。所属各企业先后经过“标准宣贯、分类试点、初始调查、风险评价、文件开发、体系颁布、规范运行、审核评审”等阶段,陆续建立起一整套健康、安全与环境文件管理体系。  相似文献   
90.
微波消解-氢化物发生原子荧光光度法测定土壤中的汞   总被引:1,自引:0,他引:1  
建立了微波消解-氢化物发生原子荧光光度法测定土壤中汞的方法。对微波消解条件、样品粒度等进行了优化,用3 mL硝酸和2 mL盐酸的混合酸作消解溶剂,在设定的微波条件下汞提取完全。用3%的盐酸作为反应载流,0.01%硼氢化钾与0.5%氢氧化钠的混合液为还原剂,直接定容后应用HG-AFS测定,通过测定国家标准参考物质和加标回...  相似文献   
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