中美贸易与污染避难所假说的实证研究——基于内含污染的视角

使用非竞争型投入产出表,在考虑中间产品产生污染的情况下,通过计算中美双边贸易的内含污染,考察对外贸易对发达国家和发展中国家环境的影响,检验污染避难所假说是否成立.本文首先构造中美两国28个制造业的总污染强度,在此基础上计算1987-2004年中美制造业贸易的贸易内含污染条件指标,并分析中美制造业贸易的进出口内含污染的部门来源.研究发现,1992年之后,所有污染物的贸易内含污染条件值都大于1,这意味着美国从中国进口的污染强度要高于中国从美国的进口污染强度,中美双边贸易中,中国环境受损、美国环境获利,污染避难所假说成立.从部门结构上看,中国出口内含污染主要来源于塑料制品、机械设备和工业化学这三个部门,进口内含污染主要来源于工业化学、机械设备和交通设备这三个部门.     

基于相对资源承载力的青岛市主体功能区区划

本文根据相对资源承载力研究方法,以全国作为参照区域计算了2005～2008年青岛市主要辖区相对自然资源承载力、相对经济资源承载力和综合承载力.分析结果表明:①对于相对自然资源承载力而言,平度市处于富余状态;莱西市处于临界状态;胶州市、即墨市、胶南市处于超载状态:青岛市市区则处于严重超载状态.相对自然资源承载力序列(由富余到超载):平度市>莱西市>胶州市>胶南市>即墨市>市区.②青岛市各辖区相对经济资源承载力全部处于富余状态,其中市区的相对经济资源承载能力最大.相对经济资源承载力序列(由富余到超载):市区>胶州市>胶南市>即墨市>藁西市>平度市.③青岛市各主要辖区综合承载力全部处于富余状态,且基本保持稳定.综合承载力序列(由大到小):市区>平度市>即墨市>胶州市>胶南市>莱西市.在此基础上.本文对青岛市2005-2008期间主要辖区的主体功能区进行了区划,结果显示青岛市所辖6市区均属于优化开发区,在"十二五"期间.产业调整与优化仍是区域可持续发展的重中之重.     

关于减排技术途径和政策的探讨

通过对发达国家先进的节能减排技术和政策,以及我国现阶段所采取的减排技术政策的分析,通过对我国重点行业二氧化硫和化学需氧量的减排技术现状对策研究,对适合我国减排的技术途径和配套政策进行探讨。     

钛基IrO2-SnO2电极在烟气海水脱硫恢复系统中的应用

采用浸渍-热分解法制备了含IrOx-TiO2中间层的IrO2-SnO2电极,得到的电极具有较高的析氯电催化活性和较强的稳定性,并通过电化学氧化法对Na2SO3海水脱硫模拟液进行处理,考察了电流密度、温度、pH值和电解时间等电解工艺参数对Na2SO3去除率和化学需氧量COD的影响。结果表明,在电流密度为200 mA/cm^2,pH值为3.5,电解440 mg/L的Na2SO3海水脱硫模拟液,15 min时Na2SO3去除率可达96.5%,COD去除率可达82.6%。     

长江水体溶解有机质与金属离子作用污染分析

将万州区牌楼段的长江水与金属离子混合,通过测定荧光光谱得出,在金属离子质量浓度较低(1.0×10-7 mg/mL)时,长江水中的腐殖质与金属离子发生螯合作用而使荧光强度降低,而在更高浓度时,则由于吸附/解吸作用而使荧光强度增强.三维荧光谱图的测定结果表明,金属离子浓度的大小决定了其与腐殖质的基团反应类型.实验结果表明,...     

钛基IrO2-SnO2电极在烟气海水脱硫恢复系统中的应用

采用浸渍-热分解法制备了含IrOx-TiO2中间层的IrO2-SnO2电极,得到的电极具有较高的析氯电催化活性和较强的稳定性,并通过电化学氧化法对Na2SO3海水脱硫模拟液进行处理,考察了电流密度、温度、pH值和电解时间等电解工艺参数对Na2SO3去除率和化学需氧量COD的影响.结果表明,在电流密度为200 mA/cm...     

生物滤塔-人工湿地组合工艺对农村生活污水净化效果研究

采用厌氧/射流充氧生物滤塔/人工湿地组合工艺处理农村生活污水,考察了组合工艺及其各处理单元对污染物去除的贡献率。在实验室进行了小试,实验结果表明：该组合工艺对污染物具有较好的去除效果,在稳定工况下,组合工艺对COD、NH4＋-N、TN和TP的平均去除率分别为85.4%、74.5%、75.9%和78.3%。生物滤塔能有效...     

Evaluation of photolysis and hydrolysis of pyraclostrobin in aqueous solutions and its degradation products in paddy water

This study evaluated the hydrolysis and photolysis kinetics of pyraclostrobin in an aqueous solution using ultra-high-performance liquid chromatography–photodiode array detection and identified the resulting metabolites of pyraclostrobin by hydrolysis and photolysis in paddy water using high-resolution mass spectrometry coupled with liquid chromatography. The effect of solution pH, metal ions and surfactants on the hydrolysis of pyraclostrobin was explored. The hydrolysis half-lives of pyraclostrobin were 23.1–115.5?days and were stable in buffer solution at pH 5.0. The degradation rate of pyraclostrobin in an aqueous solution under sunlight was slower than that under UV photolysis reaction. The half-lives of pyraclostrobin in a buffer solution at pH 5.0, 7.0, 9.0 and in paddy water were less than 12?h under the two light irradiation types. The metabolites of the two processes were identified and compared to further understand the mechanisms underlying hydrolysis and photolysis of pyraclostrobin in natural water. The extracted ions obtained from paddy water were automatically annotated by Compound Discoverer software with manual confirmation of their fragments. Two metabolites were detected and identified in the pyraclostrobin hydrolysis, whereas three metabolites were detected and identified in the photolysis in paddy water.     

Determination of the residue dynamics and dietary risk of thiamethoxam and its metabolite clothianidin in citrus and soil by LC-MS/MS

A modified quick, easy, cheap, effective, rugged and safe (QuEChERS) method was developed for the determination of thiamethoxam and its metabolite clothianidin in citrus (including the whole citrus, peel and pulp) and soil samples by liquid chromatography-tandem mass spectrometry. The sample was extracted with acetonitrile and purified with octadecylsilane. The detection limits of both compounds were 0.0001–0.0002?mg kg^–1, while the limit of quantification of thiamethoxam was 0.002?mg kg^–1 and the limit of quantitation of metabolites was 0.001?mg kg^–1. The recovery was 70.37%–109.76%, with inter-day relative standard deviations (RSD) (n?=?15) values ≤9.46% for the two compounds in the four matrices. The degradation curve of thiamethoxam in whole citrus and soil was plotted using the first-order kinetic model. The half-life of the whole citrus was 1.9–6.2?days, and the half-life of the soil was 3.9–4.2?days. The terminal residue of thiamethoxam (the sum of thiamethoxam and clothianidin, expressed as thiamethoxam) was found to be concentrated on the peel. The final residual amount of thiamethoxam in the edible portion (pulp) was less than 0.061?mg kg^–1. The risk quotient values were all below 1, indicating that thiamethoxam as a citrus insecticide does not pose a health risk to humans at the recommended dosage.     

Analysis of metabolic changes in Trichoderma asperellum TJ01 at different fermentation time-points by LC-QQQ-MS

Trichoderma spp. are among the most widely recognized biocontrol fungi used to inhibit pathogens and promote plant growth. These functions are related to primary and secondary metabolites. This study investigated the different metabolites in Trichoderma asperellum TJ01 cultured for 24 and 72?h using liquid chromatography with triple-quadrupole mass spectrometry. Compared to the 24?h culture of T. asperellum TJ01, the 72?h culture with amino acid metabolism tended to decrease while sugar and lipid metabolisms tended to increase. Furthermore, the 72?h culture had a higher proportion of upregulated flavonoids, in combination with a higher proportion of downregulated alkaloids, and equal proportions of upregulated and downregulated polyphenols and hormones. This study also identified a few valuable medicinal substances such as trigonelline and 5-hydroxytryptophan in T. asperellum TJ01 fermentation cultures.