基于膨胀土蠕变试验的粘弹性模型对比研究

对广西南宁膨胀土进行了一系列室内压缩蠕变试验,得出了相应的蠕变曲线.运用K-H体模型和Bu体模型进行对比研究,确定了正常应力条件下非饱和南宁膨胀土的粘弹性模型和各流变常数,提出了正常应力条件下南宁膨胀土的本构方程及蠕变方程.为膨胀土工程设计和分析提供可靠的理论依据.     

膜蒸馏技术在石化废水处理领域的应用进展

综述了一种新型分离技术——膜蒸馏技术在石化废水处理领域的应用现状,重点介绍了在高盐度废水处理和挥发性有机物废水处理两个方面的进展;指出膜蒸馏应用过程中存在的主要问题是膜污染;预测了膜蒸馏及其集成技术在废水处理领域的发展前景。     

基于数字图像处理技术的金相分析研究

采用和改进了人际交互式图像分割算法Live-wire,对电气火灾中的典型火烧金相图和一次短路金相图进行处理,结合数字形态学操作,精确提取了两类金相图中的典型胞状晶和柱状晶结构;分析和讨论了多种结构描述子对晶格分类的作用,结果表明,离心率和晶格标记方差两个描述子能有效区分两类晶格结构;采用聚类分析和Fisher判别法,实现了对两类金相图的自动分类.     

安全工程学科发展与专业办学思路的思考

迎合安全工程教育的蓬勃发展,结合上海应用技术学院安全工程专业建设的历史以及人才培养现状,分析了上海经济形势和学科专业教育教学方向,总结了安全工程学科的探索思路以及办学拓展方向,提出了专业课程模块方向与课程设置,供安全工程教育工作者参考.     

CO2 emission driving forces and corresponding mitigation strategies under low-carbon economy mode: evidence from China’s Beijing–Tianjin–Hebei region

On account of the background of China’s “new normal” characterized by slower economic growth, this paper analyses the low-carbon economy status quo in the Beijing–Tianjin–Hebei region and empirically investigates the relationship between carbon dioxide (CO₂) emissions and its various factors for China’s Beijing–Tianjin–Hebei region using panel data econometric technique. We find evidence of existence of Environmental Kuznets Curve. Results also show that economic scale, industrial structure, and urbanization rate are crucial factors to promote CO₂ emissions. However, technological progress, especially the domestic independent research and development, plays a key role in CO₂ emissions abatement. Next, we further analyze the correlation between each subregion and various factors according to Grey Relation Analysis. Thereby, our findings provide important implications for policymakers in air pollution control and CO₂ emissions reduction for this region.     

太原市土壤六六六和滴滴涕的暴露格局及健康风险

为研究六六六(HCHs)和滴滴涕(DDTs)在太原市不同功能区土壤中的暴露格局、来源以及对周围人群的健康风险,在太原市化工区、灌区、矿区、生态区周边荒地土壤中进行采样,分析测定了土壤中HCHs和DDTs含量,根据太原市人群实际情况的暴露参数和USEPA的部分参数,对土壤HCHs和DDTs的健康风险进行评价。结果表明:1)太原市表层土壤中HCHs的平均含量大小依次为化工区>灌区>矿区>生态区;DDTs平均含量的大小依次为化工区>灌区>矿区>生态区,仅6%的HCHs和3%的DDTs和的平均残留水平均高于我国土壤质量标准一级标准,但均不超过二级标准值;2)土壤中HCHs残留主要源于历史上林丹的使用,DDTs残留则来源于历史和新污染源的共同影响;3)太原市表层土壤HCHs和DDTs致癌风险大小为化工园区>矿区>灌区>生态区。非致癌风险大小为化工区>矿区>灌区>生态区。3种暴露途径的在不同功能区的健康风险贡献率大小均为经口摄入>呼吸吸入>皮肤接触;综合来看太原市表层土壤中的HCHs和DDTs并未对人类造成非致癌风险,但有一定的致癌风险。本文的研究结果可为太原市土壤质量评价和环境污染防治提供科学指导,并对太原市人群的健康风险防治提供依据。     

Fate of antimicrobial resistance genes in response to application of poultry and swine manure in simulated manure-soil microcosms and manure-pond microcosms

This study aimed to determine the occurrence, abundance, and fate of nine important antimicrobial resistance genes (ARGs) (sul1, sul2, tetB, tetM, ermB, ermF, fexA, cfr, and Intl1) in the simulated soil and pond microcosms following poultry and swine manure application. Absolute quantitative PCR method was used to determine the gene copies. The results were modeled as a logarithmic regression (N?=?mlnt?+?b) to explore the fate of target genes. Genes sul1, Intl1, sul2, and tetM had the highest abundance following the application of the two manure types. The logarithmic regression model fitted the results well (R ² values up to 0.99). The reduction rate of all genes (except for the genes fexA and cfr) in manure-pond microcosms was faster than those in manure-soil microcosms. Importantly, sul1, intl1, sul2, and tetM had the lowest reduction rates in all the samples and the low reduction rates of tetM was the first time to be reported. These results indicated that ARG management should focus on using technologies for the ARG elimination before the manure applications rather than waiting for subsequent attenuation in soil or water, particularly the ARGs (such as sul1, intl1, sul2, and tetM investigated in this study) that had high abundance and low reduction rate in the soil and water after application of manure.     

Physiological mechanisms of a wetland plant (Echinodorus osiris Rataj) to cadmium detoxification

Environmental Science and Pollution Research - Physiological responses of Echinodorus osiris Rataj plant under cadmium (Cd) stress (5 and 15 mg L?1) were studied by...     

Spatial variation and toxicity assessment for heavy metals in sediments of intertidal zone in a typical subtropical estuary (Min River) of China

Environmental Science and Pollution Research - Sediment samples were collected in five marshes (C1, Phragmites australis marsh; C2, P. australis and Cyperus malaccensis marsh; C3, C. malaccensis...     

Effect of copper(II) on biodegradation of benzo[a]pyrene by Stenotrophomonas maltophilia

Benzo[a]pyrene (BaP) biodegradation by Stenotrophomonas maltophilia was studied under the influence of co-existed Cu(II) ions. About 45% degradation was achieved within 3 d when dealing with 1 mg L^?1 BaP under initial natural pH at 30 °C; degradation reached 48% in 2 d at 35 °C. Efficacy of BaP biodegradation reached the highest point at pH 4. In the presence of 10 mg L^?1 Cu(II) ions, the BaP removal ratio was 45% on 7th day, and maintained stable from 7 to 14 d at 30 °C under natural pH. The favorable temperature and pH for BaP removal was 25 °C and 6.0 respectively, when Cu(II) ions coexisted in the solutions. Experiments on cometabolism indicated that S. maltophilia performed best when sucrose was used as an additional carbon source. GC–MS analysis revealed that the five rings of BaP opened, producing compounds with one or two rings which were more bioavailable.