Fenton试剂在返排压裂液处理中的应用

油气田压裂作业后的返排残余压裂液黏度、有机物含量以及浊度都较高,对油田企业周围的生态环境,尤其是农作物及地表水造成严重污染。经过破胶—絮凝处理后,COD仍然较高。文章以胜利油田水基胍胶返排压裂液为研究对象,针对破胶—絮凝处理后的上清液,采用Fenton试剂深度氧化处理,处理后压裂液COD去除率可达99.3%,满足GB 8978-1996《污水综合排放标准》二级排放标准。     

"绿色"离消费者太遥远

自从有了"3·15"消费者权益日,有了全国质量万里行活动,消费者在吃穿用等方面,无论有了什么问题都可以进行投诉.但是,目前反复出现的问题,消费者反复投诉的问题,亦是屡禁不止的问题.这说明法律被搁置或者说根本没有起作用.真正的"绿色"产品仍然蒙着面纱,看不清也难摸倒.那些给消费者带来伤害的商品,依旧处处皆是,堂而皇之的在货架上摆着.消费者提心吊胆而又很无奈.每每道来,还是请消费者多注意,公平吗?我们不能要求消费者成为知识渊博的万能者,而问题在于如何把不合格的产品彻底消灭.现在,媒体经常将厂家或造假的黑窝点暴露出来,起到了一定的遏制作用.但是,制裁还应加大力度,不给黑商家有喘息翻身的机会.当然,眼下还是把有问题的商品实录下来,让消费者知情、了解,有选择、有对策,做到心中有数,谨防上当受骗.     

Inhibition mechanism of fermentation broth extract of Phomopsis sp. Strain S4 on cell membranes of Magnaporthe oryzae北大核心CSCD

The secondary metabolites of endophytic Phomopsis sp. strain S4 show antifungal activity against a variety of plant pathogens, which implies that strain S4 has potential prospect in crop disease control. The aim of this study was to explore the inhibition mechanisms of S4 against plant pathogenic fungi. Magnaporthe oryzae was used as the main pathogenic material for the research. Cell membrane changes were detected using antifungal experiments, scanning electron microscopy, Q RT-PCR, and cell content leaking experiments. The results of scanning electron microscopy showed that M. oryzae mycelia, after treatment with S4 fermented product extract, decreased in size, suggesting the integrity of the cell membrane was destroyed. The genes related to ergosterol synthesis, which plays an important role in membrane integrity, were studied though Q RT-PCR. The results showed that the expression levels of ERG1, ERG11, and ERG6 genes were down-regulated by 2.0, 1.40, and 2.7-fold, respectively, whereas that of ERG7 was up-regulated by 1.38-fold, which means the ergosterol synthesis pathway was destroyed. The physiological experiments also showed that the cell contents of M. oryzae mycelia treated with S4 fermented product extract leaked significantly, which was consistent with the Q RT-PCR results. The results showed that S4 fermentation broth exact could destroy the cell membrane integrity by inhibiting ergosterol synthesis, and eventually inhibit M. oryzae cell growth. © 2018 Science Press. All rights reserved.     

农田土壤中汞的吸附分配行为研究

汞是环境中毒性最强的重金属之一,由于具有持久性、长距离迁移性和生物累积性被列为全球性污染物。土壤是汞重要的源和汇,在汞的生物地球化学循环中发挥关键作用,其理化性质可以显著影响汞的吸附分配行为。本文基于采自全国各地的131份农业土壤样品考察了汞(Hg2+)在土壤中的吸附分配行为,测定了Hg2+的固液分配系数(Kd),并探讨其与p H、有机质(OM)、粒度组成、溶解性有机质(DOM)和总硫等土壤理化性质的关系。利用逐步多元线性回归的方法分析发现旱地土壤对汞Kd的主要影响因素是DOM和土壤粒度,而水田的主要影响因素是总硫。通过淹水实验,进一步探究了土壤氧化还原对Hg2+分配的影响。研究发现,旱地土壤中,大部分土壤在淹水30 d后Kd呈明显增大趋势,继续淹水至60 d的Kd表现为稳定或下降的趋势;大部分水田土壤在淹水条件下Kd未表现出增大的趋势,且随淹水时间呈稳定或下降的趋势。     

铀尾矿库区稻田土中放射性核素的空间分布和放射性水平评价

以我国南方某铀尾矿库下游稻田土壤为研究对象,通过现场取样与室内检测,对土壤中放射性核素238U、226Ra、232Th、40K的比活度进行空间分析。同时采用γ辐射吸收剂量率和年有效剂量法进行土壤环境放射性水平评价,得出土壤中所检测的4种典型核素放射性比活度差异较大。在土壤表层和剖面,226Ra和40K的均值、最大比活度和标准差均较高,232Th和238U较低。而226Ra含量超出当地背景值较多。剖面上4种放射性核素比活度均有随深度降低的趋势,高值出现在土壤浅层,这可能与土壤的有机质含量等有关。综合垂向和平面上的分布特征可知核素232Th、40K的迁移能力比238U、226Ra弱。放射性水平评价结果显示:研究区土壤年有效剂量率平均值小于联合国原子辐射效应科学委员会和全国年有效剂量率的推荐背景值,但是γ辐射吸收剂量率均值高出全国和世界平均水平的3倍。准确定量评价了尾矿库对居民造成的辐射影响,同时为放射性核素在周边稻田植物根系中的迁移机理研究提供基础资料。     

液化气球罐区消防演练过程问题分析及对策

对液化气球罐区泄漏消防演练过程存在的问题进行了分析,提出了整改措施和建议.     

水灰比对高温下混凝土质量损失及抗压强度影响试验研究

为研究水灰比对不同温度作用下混凝土残余抗压强度、质量损失的影响,对不同受火温度和不同水灰比的混凝土标准立方体试件进行高温下及高温后的抗压强度试验和质量损失测试。试验结果表明:随着水灰比的增大,高温下及高温后混凝土抗压强度、混凝土质量损失均呈现出整体下降的趋势。通过试验拟合回归分析,建立了高温下混凝土抗压强度、质量损失与受火温度之间的关系式,可通过质量损失、受火温度来预估高温下混凝土残余抗压强度。     

全国死亡百人以上事故统计分析

本文统计了1990～2005年我国死亡百人以上的事故。此类事故共计25起，总死亡人数4340人。此外，进一步分析了这些事故的类型、所属行业和发生时间等，找出了事故发生的规律。最后，对死亡百人以上事故的预防提出了对策建议。     

基于行为科学的组织安全管理方案模型

社会组织的安全管理工作方法的集合可以看做是该组织的安全管理方案,根据文化导向组织行为,组织行为决定个人行为的行为科学基本原理,该安全管理方案可以结构化为由安全文化、组织结构和安全方法3个基本模块组成的模型。其工作原理,即安全管理原理,是该模型运行产生组织内员工的安全知识、安全意识、安全习惯等中间结果和组织员工的安全行为、安全设施的安全状态以及组织安全业绩等最终结果。组织安全管理方案模型的优劣可以用诊断方法量化诊断,其运行结果也可以用个人行为纠正方法进行补充改善。组织安全管理方案模型内的内容组成了安全科学技术学科的主体内容,也是本学科学历教育方案形成、发展的依据。     

Applying hexagonal nanostructured zeolite particles for acetone removal

This study examines the performance of a new adsorbent, hexagonal nanostructured zeolite particles (HNZP) for acetone adsorption and compares the results with that of commercial mobil synthetic zeolite-5 (ZSM-5) type zeolite. The HNZP is a pure siliceous adsorbent with different values of pore diameter and surface area being adjustable by the manufacturing condition. The results indicate that a slight increase in the average pore diameter (d) of HNZP from 2 to 2.5 nm leads to an increase in the acetone adsorption capacity, although its surface area is decreased, in which case (d = 2.5 nm) the adsorption capacity of fresh HNZP is better than that of ZSM-5 zeolite. Even for the fresh HNZP (d = 2 nm) of which the adsorption capacity is less than that of the ZSM-5 zeolite at relative humidity (RH) of 0%, its adsorption capacity is not deteriorated after repeated regeneration, but the adsorption capacity of regenerated ZSM-5 zeolite decays markedly. Thus, after only one regeneration, the adsorption capacity of HNZP (d = 2 nm) becomes better than that of the ZSM-5 zeolite. The decrease in the adsorption capacity of regenerated ZSM-5 zeolite might be because of its aluminum content that catalyzes the acetone into coke and, thus, blocks the adsorption sites. Furthermore, result on the moisture effect shows that because the pure siliceous HNZP was more hydrophobic than the ZSM-5 zeolite, the acetone adsorption efficiency of fresh HNZP (d = 2 nm) is better than that of ZSM-5 zeolite at RH = 50%.