我国土壤中重金属铜的生物配体模型的建立与应用

关于重金属污染的风险评价及其预测模型日益成为环境领域的研究热点。近年来,一种用于预测和评价环境中重金属生物毒性的机理性模型一生物配体模型(BLM)被广泛应用于水体及陆地生态系统。本研究以我国土壤的陆地生物配体模型(TBLM)建构为目标,以土壤溶液系统为媒介,通过17种土壤上重金属铜离子与大麦根长的相互作用关系,发现了土壤中Cu-TBLM的主要影响因素为Cu~(2+)、CuOH~+、Mg~(2+)以及铜离子与大麦根系表面的专性结合能力。基于模型大麦根长预测值与实测值之间的相关关系,通过数学拟合功能求得TBLM中各参数值为logK_(CuBL)=4.87、logK_(CuOH)+=7.62、logK_(MgBL)=1.91、f~(50%)=0.103、β=1.09。本研究所得到的TBLM模型能很好地预测我国土壤中铜对大麦根长的毒害程度,预测值与实测值的相关性达到了90%。本研究结果不仅可以为我们降低重金属离子生物有效性提供有力的理论借鉴,更对我国土壤环境质量保护和长期良性可持续发展具有重要意义。文160余篇。     

Dissimilatory reduction of FeIII (EDTA) with microorganisms in the system of nitric oxide removal from the flue gas by metal chelate absorption

In the system of nitric oxide removal from the flue gas by metal chelate absorption, it is an obstacle that ferrous absorbents are easily oxidized by oxygen in the flue gas to ferric counterparts, which are not capable of binding NO. By adding iron metal or electrochemical method, Fe^Ⅲ (EDTA) can be reduced to Fe^Ⅱ(EDTA).However, there are various drawbacks associated with these techniques. The dissimilatory reduction of Fe^Ⅲ(EDTA) with microorganisms in the system of nitric oxide removal by metal chelate absorption was investigated. Ammonium salt instead of nitrate was used as the nitrogen source, as nitrates inhibited the reduction of Fe^Ⅲ due to the competition between the two electron acceptors. Supplemental glucose and lactate stimulated the formation of Fe^Ⅱ more than ethanol as the carbon sources. The microorganisms cultured at 50~C were not very sensitive to the other experimental temperature, the reduction percentage of Fe^Ⅲ varied little with the temperature range of 30-50℃.Concentrated Na2 CO3 solution was added to adjust the solution pH to an optimal pH range of 6-7. The overall results revealed that the dissimilatory ferric reducing microorganisms present in the mix-culture are probably neutrophilic, moderately thermophiUc Fe^Ⅲ reducers.     

户外运动服装的开发及发展趋势探析

随着生活方式的多元化发展,户外运动受到越来越多人的关注和喜爱。户外运动用品店如雨后春笋应运而生。因此具有防护功能的户外运动服装特别受到青睐。本文综述了户外运动服装的需求和分类,分析了户外运动服装的结构和功能性设计思路,并论述了未来户外运动服装的发展趋势。     

重金属人体生物有效性、吸收及毒性研究中的肠道细胞模型

重金属污染对人体健康产生极大威胁,因而备受关注.肠道吸收是人体重金属暴露的主要途径之一,因此,重金属的生物有效性、肠道吸收过程和毒性研究成为当前的研究热点.体外胃肠模拟法和动物模型被广泛用于重金属的相关研究,然而体外胃肠模拟法缺少人体肠道细胞成分,动物模型与人体存在着物种差异且实验成本高.鉴于此,研究者开发了能够部分模拟人体肠道上皮功能的体外肠道细胞模型.此模型作为研究生物有效性的重要工具,能模拟肠道对重金属的吸收转运过程,并能够结合分子生物学等技术、采用多学科交叉的研究方法探索重金属的肠吸收和肠毒性的分子机制.本文系统介绍了人肠上皮的结构功能、肠道上皮细胞对重金属吸收转运机制、肠道细胞模型的发展及其在重金属相关研究中的应用与优缺点,总结了肠细胞模型功能验证指标和优化方法.同时,还对肠道微流控培养系统(芯片肠道)和肠类器官等三维肠细胞模型技术的最新进展进行了介绍和展望.     

新生态MnO2吸附剂对酸性媒介染料废水脱色特性研究

本文主要报道了一种用于染料废水处理的新型材料即新生态MnO2 及其对三种酸性媒介染料染色废水的脱色作用及影响脱色效果的主要因素。研究结果表明 ,新生态MnO2 对酸性媒介染料的吸附能力很强 ,当染料浓度为2 0 0mg/L、pH <2时 ,其对酸性媒介黑T、酸性媒介绿G和酸性媒介黄GG的脱色率分别达 98.2 %、94.5 %和 96 .4%。染料吸附效果受体系pH值、MnO2 投加量、吸附时间及温度等因素的影响 ,其中pH值是最主要的影响因素。新生态MnO2 对酸性媒介黄GG的吸附作用符合Langmuir吸附等温式     

Multilevel air quality evolution in Shenyang: Impact of elevated point emission reduction

Visibility observed at different altitudes is favorable to understand the causes of air pollution. We conducted 4-years of observations of visibility at 2.8 and 60 m and particulate matter(PM) concentrations from 2015 to 2018 in Shenyang, a provincial city in Northeast China. The results indicated that visibility increased with the increasing height in winter(especially at night), and decreased with height in summer(especially at the daytime). PM concentration exhibited opposite vertical variati...     

Insight into the dynamic microbial community and core bacteria in composting from different sources by advanced bioinformatics methods

Microbial communities are important for high composting efficiency and good quality composts. This study was conducted to compare the changes of physicochemical and bacterial characteristics in composting from different raw materials, including chicken manure (CM), duck manure (DM), sheep manure (SM), food waste (FW), and vegetable waste (VW). The role and interactions of core bacteria and their contribution to maturity in diverse composts were analyzed by advanced bioinformatics methods combined sequencing with co-occurrence network and structural equation modeling (SEM). Results indicated that there were obviously different bacterial composition and diversity in composting from diverse sources. FW had a low pH and different physiochemical characteristics compared to other composts but they all achieved similar maturity products. Redundancy analysis suggested total organic carbon, phosphorus, and temperature governed the composition of microbial species but key factors were different in diverse composts. Network analysis showed completely different interactions of core bacterial community from diverse composts but Thermobifida was the ubiquitous core bacteria in composting bacterial network. Sphaerobacter and Lactobacillus as core genus were presented in the starting mesophilic and thermophilic phases of composting from manure (CM, DM, SM) and municipal solid waste (FW, VW), respectively. SEM indicated core bacteria had the positive, direct, and the biggest (>?80%) effects on composting maturity. Therefore, this study presents theoretical basis to identify and enhance the core bacteria for improving full-scale composting efficiency facing more and more organic wastes.

     

Association between short-term exposure to ambient air pollution and number of outpatient Helicobacter pylori infection visits

Environmental Science and Pollution Research - Helicobacter pylori infection (HPI) is an important risk factor of gastrointestinal diseases, but factors leading to it are still not fully...     

Study on macro-meso mechanical properties of cemented tailings backfill with high fly ash content

Environmental Science and Pollution Research - The use of cement and fly ash (FA) to prepare cemented tailings backfill (CTB) lowers backfill mining costs while also reducing pollution caused by...     

Pyroligneous acids from biomass charcoal by-product as a potential non-selective bioherbicide for organic farming: its chemical components,greenhouse phytotoxicity and field efficacy

Environmental Science and Pollution Research - Effective and environmentally friendly herbicides are urgently needed to meet consumer demand for organic products. To evaluate the weed control...