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11.
Xian T. Lu Yun Ma Cui Wang Xiao F. Zhang Da Q. Jin Chang J. Huang 《Journal of environmental science and health. Part. B》2013,48(5):445-454
Previous studies have demonstrated that pesticides could induce cytotoxicity and genotoxicity in vivo and in vitro, and that oxidative stress may be an important factor involved. However, investigations comparing the capability of different organophosphorous (OP) compounds to induce cytotoxicity, genotoxicity and oxidative stress are limited. Hence, the aim of this paper was to access the cytotoxic and genotoxic effects of five OPs or metabolites, Acephate (ACE), Methamidophos (MET), Chloramidophos (CHL), Malathion (MAT) and Malaoxon (MAO), and to clarify the role of oxidative stress, using PC12 cells. The results demonstrated that MET, MAT and MAO caused significant inhibition of cell viability and increased DNA damage in PC12 cells at 40 mg L?1. MAO was more toxic than the other OPs. ACE, MET, MAT and MAO increased the levels of intracellular reactive oxygen species (ROS) and malondialdehyde (MDA), and decreased the activity of superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) at 20 mg L?1 and 40 mg L?1 to different degrees. Pre-treatment with vitamin E(600 μM)caused a significant attenuation in the cytotoxic and genotoxic effect; pre-treatment reversed subsequent OP-induced elevation of peroxidation products and the decline of anti-oxidant enzyme activities. These results indicate that oxidative damage is likely to be an initiating event that contributes to the OP-induced cytotoxicity. 相似文献
12.
CO2捕集回收技术研究 总被引:3,自引:0,他引:3
主要介绍了常用的胺化合物吸收法、钙基吸收剂法、金属氧化物法等CO2捕集回收技术的最新研究进展及存在的问题,综合对比了各种方法的优缺点:胺化合物吸收法吸收速率快,但再生能耗较高,因此开发"高效低耗"的复合吸收剂成为研究的重点;钙基吸收剂法在高温环境下对CO2的吸收有较好的效果,但吸收剂的碳酸化转化率及热稳定性是有待解决的关键问题;金属氧化物法具有高的CO2吸收效率,但成本较高.在此基础上,探索了CO2捕集回收技术改进工艺,提出改善吸收剂性能、开发高效低耗的CO2选择性吸收剂将成为今后CO2捕集回收技术的研究方向. 相似文献
13.
Huang WJ 《Waste management (New York, N.Y.)》2008,28(11):2403-2405
This paper reports the characterization of residues collected from air pollution controlling devices (APCDs) at seven large-scale municipal solid wastes (MSW) incineration plants. The amount of lime being sprayed in plants is a function of free CaO content in scrubber residues; a higher free CaO content in scrubber residue causes more leaching of lead. The proper amount of lime in the semi-dry scrubbing system was found to be 5kg/ton of MSW waste. Under these conditions, both the free CaO content and lead leaching became extremely low in scrubber residue. 相似文献
14.
Analysis of patterns and ecological security trend of modern oasis landscapes in Xinjiang, China 总被引:6,自引:0,他引:6
Ecological security has become so important that it will affect the national security and social sustainable development.
In this paper, a case study on the ecological security indexes of modern oasis landscapes in Beitun Oasis, Xinjiang, was carried
out. The spatial neighbouring parameters, such as the contiguous length, measure of area and patch quantity of oasis landscape
patches, affected by desert landscape patches were calculated by using GIS-based buffer analysis, the method of calculating
ecological security indexes of oasis landscape was developed, and the dynamic changes of patterns and ecological security
indexes of the oasis landscapes since recent 30 years were analyzed. The results showed that soil salinization or alkalization
and paludification were major factors affecting the ecological security in Beitun Oasis. Therefore, measures should be taken
actively to prevent and control secondary salinization and paludification. The ecological security indexes of the oasis landscape
in 1972, 1990 and 2005 were 78.91, 82.28 and 83.86, respectively, which showed the degree of security is improving, and the
environment was developing harmoniously between human and nature. The methods of evaluating ecological security based on the
spatial neighbouring relations between landscape patches can be used to reflect preliminarily the ecological security patterns
of landscapes. 相似文献
15.
16.
生物膜填料塔净化有机废气研究 总被引:38,自引:1,他引:38
为在国内开展生物化学法净化低浓度有机废气的研究工作,采用国内现有微生物菌种挂膜接种的生物膜填料塔净化低浓度甲苯废气,结果表明,在入口气体甲苯浓度0.183~1.803mg/L及气体流量86.4~190.8L/h(停留时间6.2~13.6s)的实验范围内,增加入口气体甲苯浓度和气体流量,可使甲苯的生化去除量增大,每升体积的生物膜填料对甲苯的生化去除量最大可达157.13mg/h。由实验结果推断,生物膜填料塔对废气中甲苯的净化去除过程属于传质控制过程。对比结果表明,本研究建立的动力学模式对实际过程有很好的适用性,计算值与实验值之间的相关系数R=0.98。 相似文献
17.
Effect of seed sludge on characteristics and microbial community of
aerobic granular sludge 总被引:2,自引:1,他引:2
Aerobic granular sludge was cultivated by using different kinds of seed sludge in sequencing batch airlift reactor.The influence of seed sludge on physical and chemical properties of granular sludge was studied;the microbial community structure was probed by using scanning electron microscope and polymerase chain reaction-denaturing gradient gel electrophoresis(PCR-DGGE).The results showed that seed sludge played an important role on the formation of aerobic granules.Seed sludge taken from beer wastewater treatment plant(inoculum A) was more suitable for cultivating aerobic granules than that of sludge from municipal wastewater treatment plant(inoculum B).Cultivated with inoculum A, large amount of mature granules formed after 35 days operation, its SVI reached 32.75 mL/g, and SOUR of granular sludge was beyond 1.10 mg/(g·min).By contrast, it needed 56 days obtaining mature granules using inoculum B.DGGE profiles indicated that the dominant microbial species in mature granules were 18 and 11 OTU when inoculum A and B were respectively employed as seed sludge.The sequencing results suggested that dominant species in mature granules cultivated by inoculum A were Paracoccus sp., Devosia hwasunensi, Pseudoxanthomonas sp., while the dominant species were Lactococcus raffinolactis and Pseudomonas sp.in granules developed from inoculum B. 相似文献
18.
本文目的建立个体防护装备环境适应性评价技术,为个体防护装备质量管理提供技术支持.通过分析研究国内外装备环境适应性设计要求,从装备环境工程的角度出发结合个体防护装备特点进行全面的分析设计.提出了个体防护装备的环境适应性管理、设计、实验及评价等技术方案,给出了一般个体防护装备实验室试验项目及顺序.得出环境适应性是个体防护装备重要的质量特性之一,要进一步提高个体防护装备的环境适应性技术,适应个体防护装备的发展. 相似文献
19.
据国际上有关机构统计,在各种工伤事故中。手伤害事故占25%。我国产业人口庞大。手伤害事故相应也多,因此积极制定防机械伤害手套标准用来检验控制手套的质量,对减少手伤害事故的发生至关重要。 相似文献
20.
In order to evaluate the impact of reclaimed water on the ecology of bacterial communities in the Typha angustifolia L. rhizosphere soil,bacterial community structure was investigated using a combination of terminal restriction fragment length polymorphism and 16S rRNA gene clone library. The results revealed significant spatial variation of bacterial communities along the river from upstream and downstream. For example,a higher relative abundance of γ-Proteobacteria,Firmicutes,Chloroflexi and a lower proportion ofβ-Proteobacteria and ε-Proteobacteria was detected at the downstream site compared to the upstream site. Additionally,with an increase of the reclaimed water interference intensity,the rhizosphere bacterial community showed a decrease in taxon richness,evenness and diversity. The relative abundance of bacteria closely related to the resistant of heavy-metal was markedly increased,while the bacteria related for carbon/nitrogen/phosphorus/sulfur cycling wasn't strikingly changed. Besides that,the pathogenic bacteria markedly increased in the downstream rhizosphere soil since reclaimed water supplement,while the possible plant growth-promoting rhizobacteria obviously reduced in the downstream sediment.Together these data suggest cause and effect between reclaimed water input into the wetland,shift in bacterial communities through habitat change,and alteration of capacity for biogeochemical cycling of contaminants. 相似文献