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241.
242.
酸雨对建筑材料的影响及防治研究综述 总被引:1,自引:0,他引:1
综合分析了酸雨对建筑外墙的涂料、石材、混凝土等主要建筑构件的腐蚀原理,并提出了防治措施,来预防酸雨对建筑材料的侵害。 相似文献
243.
光/电Fenton牺牲阳极法降解有机污染物 总被引:2,自引:1,他引:1
采用Fe片为阳极和石墨为阴极,在可见光(λ450 nm)照射并外加电压条件下,以有机染料橙Ⅱ(orangeⅡ)及有机无色小分子2,4-二氯苯酚(2,4-dichlorophenol,DCP)为目标化合物,探讨了光/电Fenton牺牲阳极法降解有机污染物的最佳反应条件,结果表明,在电压=3 V,pH=3.0,H2O2浓度为5×10-5mol/L时,orangeⅡ的降解效果最好,反应10 h矿化率可达到78%,210 min内2,4-DCP降解率为91.4%。通过对光/电Fenton体系原位循环伏安参数测定及过氧化物酶催化反应吸光光度法和苯甲酸荧光分析法检测光/电Fenton降解orange II过程中H2O2和羟基自由基(.OH)的变化,表明orangeⅡ降解过程涉及.OH历程。 相似文献
244.
245.
Yu-Yang Long Li-Fang Hu Jing Wang Cheng-Ran Fang Ruo He Dong-Sheng Shen 《Environmental science and pollution research international》2010,17(9):1539-1546
Purpose
To protect the environmental quality of soil, groundwater, and surface water near the landfill site, it is necessary to make an accurate assessment of the heavy metal mobility. This study aims to present the bio-immobilization behavior of heavy metals in landfill and provide some reference suggestion for the manipulation of heavy metal pollution control after closure. 相似文献246.
Biswas D Herrera P Fang L Marquardt RR Ricke SC 《Journal of environmental science and health. Part. B》2010,45(8):790-795
The cross-reactivity of egg yolk antibodies specific to antigens of Salmonella Enteritidis and Salmonella Typhimurium to killed bacterial cells of common Salmonella serovars were tested using an indirect Enzyme Linked Immunosorbent Assay (ELISA). Egg yolk antibodies were produced against purified fimbriae, flagella and lipopolysaccharide (LPS) of S. Enteritidis strain ATCC13076 and flagella, LPS and outer membrane proteins (OMP) of S. Typhimurium strain ATCC13311. For immunological specificity of egg yolk antibodies against killed bacterial cells, we found that the titers of the anti-S. Enteritidis egg yolk antibodies were higher than those of the anti-S. Typhimurium antibodies. In the evaluation of cross-reactivity of these egg yolk antibodies to various Salmonella serovars, we observed that the anti-S. Enteritidis antibodies exhibited more specific affinity than those of the anti-S. Typhimurium antibodies. All S. Enteritidis strains reacted specifically with the anti-S. Enteritidis fimbrial and flagellar egg yolk antibody whereas anti-S. Enteritidis LPS and anti-S. Typhimurium LPS, OMP and flagellar antibodies displayed non-specific reactivity to all Salmonella serovars used in this study. This finding suggests that it may be possible to design a anti-fimbrial egg yolk antibody of S. Enteritidis as a diagnostic tool and a cocktail of OMP and LPS antigens of S. Enteritidis and S. Typhimurium could be used for administering broad spectrum passive immunity to protect against the colonization of pathogenic Salmonella strains in food animals. 相似文献
247.
复合垂直流人工湿地除磷正交试验研究 总被引:1,自引:0,他引:1
为了确定复合垂直流人工湿地的流程、水力负荷、pH、COD对TP去除率的影响和提高除磷效果,选择了美人蕉和风车草构建的复合垂直流人工湿地试验系统,开展除磷的正交试验研究。采用SPSS13.0软件对正交试验结果进行方差分析,确定各因素显著性及优选条件。结果表明,复合垂直流人工湿地流程、水力负荷、pH、COD对除磷效果均有影响,其中流程对TP去除率影响显著,COD对TP去除率影响不显著。各因素对TP去除率的影响程度依次为:流程水力负荷pHCOD。除磷优选条件:COD为225mg/L,pH为8,流程为1100mm,水力负荷为181.25L/(m2.d)。 相似文献
248.
微波协同活性炭处理偶氮染料废水的研究 总被引:3,自引:1,他引:2
以粉末活性炭为催化剂,采用微波协同活性炭工艺,对偶氮染料(酸性芷青GGR和酸性嫩黄G)废水进行处理。考察了活性炭用量、微波功率、辐射时间、偶氮染料初始浓度对2种偶氮染料去除率的影响。实验结果表明,酸性芷青GGR初始质量浓度为100mg/L、活性炭用量为12.5g/L、微波辐射时间为10min、微波功率为500W条件下,酸性芷青GGR的去除率可达90.28%;酸性嫩黄G初始质量浓度为100mg/L、活性炭用量为10.0g/L、微波辐射时间为8min、微波功率为500W条件下,酸性嫩黄G的去除率可达95.87%;微波协同活性炭处理2种偶氮染料的反应均呈现一级反应动力学特征。 相似文献
249.
Agricultural Productivity Changes Induced by the Sloping Land Conversion Program: An Analysis of Wuqi County in the Loess Plateau Region 总被引:3,自引:0,他引:3
This paper examines the agricultural productivity change induced by the Sloping Land Conversion Program (SLCP) using the Malmquist
index method and household data collected from Wuqi. We find that during the period of 1998–2004, the total factor productivity
(TFP) grew by 15.8%. While numerous households suffered a TFP decline, the majority of them experienced a large gain. By decomposing
the TFP, we further show that its increase is due exclusively to the improvement of technical efficiency rather than to technological
change. To validate these findings and put them in perspective, we also estimated the TFP change with county-level aggregate
data. It is revealed that driven by technological change and scale efficiency, the TFP grew slightly during the period of
1992–1998. Because of the tremendous cropland reduction and production mode shift caused by implementing the SLCP, the TFP
declined substantially during the first three years of the program; due to continued improvement of technical efficiency;
however, its growth accelerated later. Altogether, our evidence consistently suggests that implementing the SLCP has contributed
to the agricultural TFP growth in the longer term and that the efficiency improvement has resulted mainly from the increased
public expenditures for extension services and diffusion of technical knowledge. Wuqi’s experience proves that it is possible
to achieve environmental conservation and increase productivity simultaneously, even when facing a cropland reduction and
production mode alternation. 相似文献
250.
合理的产业结构是小城镇整体经济协调发展的基础和小城镇建设健康发展的标志。在社会主义市场经济条件下,解决好小城镇产业结构与产业结构调整速度问题,对农村经济乃至整个国民经济的发展都具有重要意义。从实际调研出发,分析了中国产业状况,着重对江苏苏中通州二甲镇产业结构及其现状提出了建议与展望。 相似文献