甘蔗叶活性炭的制备

以H3PO4为活化剂制备甘蔗叶活性炭,采用正交实验对活性炭的制备工艺进行了优化,并研究了活性炭对含铬废水的吸附和再生性能.实验结果表明:在H3PO4体积分数为15％、H2SO4体积分数为6％、HC1体积分数为3％、活化温度为723 K、活化时间为0.58 h的工艺条件下,活性炭得率为35.07％,碘吸附值为1 207 mg/g.活性炭对Cr(Ⅵ)的最大平衡吸附量为30.89 mg/g,HNO3再生后对Cr(Ⅵ)的最大平衡吸附量为39.48 mg/g;再生效率最高达87.41％,经3次再生,活性炭的再生效率仍能维持在80％以上.     

A grey-relation-based method (GRM) for thermogravimetric (TG) data analysis

Journal of Material Cycles and Waste Management - Thermogravimetric analyzer was applied to analyze 22 solid materials and their mixtures at a heating rate of 10 K min−1...     

职业卫生管理中制度与文化建设的探讨

笔者借助中国职业卫生管理现状的数据,结合12年跨国公司的管理实践,运用新制度经济学的理论和引入国际职业卫生管理绩效随时间演变模型的方法,针对国内职业卫生管理存在的问题和采取的对策进行探讨与研究。结果表明,目前中国职业卫生管理现状处于初级阶段,制度和文化的建设是当前职业卫生问题的最深层原因。职业卫生管理中的制度及文化建设,对职业卫生管理绩效水平起着决定性的作用,是解决问题的最首要、最根本的手段。研究成果:文化是统帅,制度是载体,是实现理念转变的具体手段。总结并提出职业卫生文化及制度建设对策的4个要素:理念的树立与融合;全员全程参与;突出能力管理概念;量化诚信的绩效监察制度。     

圆梁山毛坝向斜段隧道涌突水灾害及对地下水的影响

深埋隧道涌突水对工程施工及区域环境都有很重要的影响 ,笔者通过圆梁山隧道毛坝向斜段涌突水监测数据 ,结合地表降水资料 ,分析了影响隧道排水量、隧道支护稳定性的主要自然因素及排水工程 ,对地表水环境产生的影响。监测和分析认为 ,隧道揭露的含水溶洞突水对当地水环境影响最大 ,也是地表降水对隧道支护产生影响的主要通道。     

Fe-pillared bentonite,a stable Fenton catalyst for treatment of petroleum refinery wastewater

Fe-pillared bentonite (Fe-Bent) was prepared by ion exchange as heterogeneous catalyst for degradation of organic contaminants in petroleum refinery wastewater. X-ray diffraction analysis showed the existence of α-Fe₂O₃. The effects of pH, H₂O₂ concentration, and catalyst dosage on the rate of lowering the chemical oxygen demand (COD) were investigated in detail. Removal efficiency of COD can be up to 92% under the following conditions: dosage of Fe-Bent 7 g L^?1, pH value 3, and H₂O₂ concentration 10 mmol L^?1. Fe-Bent showed good stability for the degradation of organics in petroleum refinery wastewater for five cycles. The adsorption of organics in wastewater onto Fe-Bent could be well described by a pseudo-second-order kinetic model.     

Effects of riparian land use on water quality and fish communities in the headwater stream of the Taizi River in China

Riparian land use remains one of the most significant impacts on stream ecosystems. This study focuses on the relationship between stream ecosystems and riparian land use in headwater regions. Four riparian land types including forest, grassland, farmland, and residential land were examined to reveal the correlation between stream water and fish communities in headwater streams of the Taizi River in north-eastern China. Four land types along riparian of 3 km in length were evaluated at 25, 50, 100, 200 and 500 m widths, respectively. Generally, the results found a significant relationship between riparian land uses and stream water quality. Grassland was positively correlated with water quality parameters (conductivity and total dissolved solids) at scales from 100 to 500 m riparian width. Farmland and residential land was negatively correlated with water quality parameters at scales from 25 to 500 m and from 50 to 200 m riparian widths, respectively. Although the riparian forest is important for maintaining habitat diversity and fish communities, the results found that only fish communities were significantly correlated with the proportion of riparian farmland. Farmland had a positive correlation with individual fish abundance within a riparian corridor of 25 to 50 m, but a negative correlation with fish diversity metrics from 25 to 100 m. This study indicates that effective riparian management can improve water quality and fish communities in headwater streams.     

垃圾填埋场恶臭气体的指纹谱

为研究垃圾填埋场恶臭污染排放现状,采用GC-MS方法分析研究了天津某垃圾填埋场春、夏季节不同采样点臭气中物质组成及主要组分含量.在所采集的样品中定量分析了111种物质,从中筛选21种物质并根据其归一化浓度值建立了各采样点的指纹谱图.结合物质嗅阈值和指纹谱分析,初步识别了各采样点的典型恶臭污染物,垃圾倾倒区包括硫化氢、甲苯、二甲二硫醚、甲硫醚、乙苯;填埋区包括甲苯、二硫化碳、乙醇、乙苯、乙酸乙酯;填埋气包括甲苯、乙苯、对二甲苯、邻二甲苯、甲硫醚.根据物质谱相似性分析,下风向恶臭物质组成主要受填埋区中恶臭污染物的影响.     

污染场地修复过程挥发性有机物散逸规律及浓度分布分析

对污染场地修复过程挥发性有机物(VOCs)散逸及浓度分布进行了检测分析,通过光离子气体检测仪(PID)现场快速监测与采样管采样气相色谱质谱分析技术相结合的方式,进行了修复过程中VOCs散逸浓度检测,同时利用吹扫捕集法+色谱/质谱检测分析方法进行了VOCs污染场地内土壤中浓度检测.研究了VOCs在挖掘扰动过程中的散逸行为,并对气体中的VOCs浓度平面分布进行分析.结果表明,污染土壤中典型VOCs的散逸率整体上较高,对于该污染场地土壤特质,污染土壤扰动过程中,1,2-二氯乙烷散逸程度最高,苯散逸程度最低.VOCs浓度并不因距离增加而呈现明显负相关关系,污染物在扩散过程中会出现波峰波谷的现象.     

氟喹诺酮类抗生素环境行为及其生态毒理研究进展

氟喹诺酮类抗生素(FQs)是治疗人和动物细菌性感染的高效广谱抗菌药,随着氟喹诺酮类抗生素在禽畜养殖业的广泛使用,由此引起的环境污染受到人们的关注。本文综述了氟喹诺酮类抗生素在水体、土壤/沉积物中的污染现状、吸附降解环境行为及其生态毒理研究进展。FQs抗生素的环境行为和风险应从环境多介质层面进行评估,同时应加强对生态毒性机理以及与其他环境污染物的联合毒性效应的研究。     

近岸海域典型水体中镉的水生态风险评估

为了解我国近岸海域重金属污染现状,以镉为目标污染物,选择北部湾、渤海湾、杭州湾、辽东湾、闽江口、珠江口、长江口、黄河口等8个典型海湾、河口区域作为评估目标区域进行水生态风险评估。研究结果显示:北部湾、渤海湾、杭州湾、闽江口、长江口、珠江口、黄河口等7个海域水体中镉的暴露水平较低,从2005至2013年其急、慢性暴露的最高潜在影响比例均低于5%,且整体呈下降趋势。辽东湾水体中镉从2005至2013年对水生生物的最高潜在影响比例为28.67%(95%置信区间26.29%~30.06%),5%、10%、15%、20%超过率对应的潜在影响比例分别为18.95%(17.84%~20.23%)、12.51%(11.65%~13.61%)、8.26%(7.40%~9.15%)、5.45%(4.62%~6.16%),其在2005—2010年间呈现略微上升趋势,2010—2013年间呈现下降趋势。水体中镉暴露水平主要受入海河流污染物输入的影响,其中五里河、大凌河影响最强。