高烈度地震区隧道软硬围岩交接段刚柔并济抗减震技术研究

为提高高烈度地震区隧道抗震性能,以某铁路隧道为研究背景,分析3种抗减震措施下隧道不同监测点隧道拱顶沉降、边墙收敛、衬砌结构PGA及最小安全系数,通过对比分析得到最优抗减震措施.结果表明:相比于工况1,工况2隧道拱顶沉降减小10.54％ ～81.10％,边墙收敛减小13.92％ ～78.77％,衬砌结构PGA减小31.4...     

钢铁行业大气环境影响评价方法与建议

按钢铁行业大气环评报告书的结构和顺序,结合HJ 2.2-2008《环境影响评价技术导则大气环境》中的相关技术要求,从评价因子、源强、评价等级、大气监测、大气预测、防护距离等方面出发,分析了钢铁行业大气环评中的评价等级确定、大气监测、大气预测等工作中存在的问题,并提出解决方案和建议对策。     

我国地震应急预案体系的现状分析

地震应急是地震救援工作的重要组成部分,科学的制订地震应急救援预案是做好应急工作的前提.本文分析了目前我国地震应急预案体系的现状,总结了地震应急预案体系中存在的问题,对于丰富和完善地震应急预案体系,使政府及社会高效、有序地做好应急响应,减少人员伤亡和财产损失具有重要的现实意义.     

Microbial reduction of uranium (VI) by Bacillus sp. dwc-2: A macroscopic and spectroscopic study

The microbial reduction of U(VI) by Bacillus sp. dwc-2, isolated from soil in Southwest China, was explored using transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and X-ray absorption near edge spectroscopy (XANES). Our studies indicated that approximately 16.0% of U(VI) at an initial concentration of 100 mg/L uranium nitrate could be reduced by Bacillus sp. dwc-2 at pH 8.2 under anaerobic conditions at room temperature. Additionally, natural organic matter (NOM) played an important role in enhancing the bioreduction of U(VI) by Bacillus sp. dwc-2. XPS results demonstrated that the uranium presented mixed valence states (U(VI) and U(IV)) after bioreduction, which was subsequently confirmed by XANES. Furthermore, the TEM and high resolution transmission electron microscopy (HRTEM) analysis suggested that the reduced uranium was bioaccumulated mainly within the cell and as a crystalline structure on the cell wall. These observations implied that the reduction of uranium may have a significant effect on its fate in the soil environment in which these bacterial strains occur.     

改进取样方法提高含油废水中CODcr值的准确度

化学需氧量(CODcr)和石油类都是中国实施水污染物排放总量控制指标,也是环境监测的常测项目.CODcr是反映水体中受还原性物质主要是有机物污染程度的综合性指标.矿物油和动、植物油统称为油类,是废水中常见的有机污染物,对CODcr的贡献较大.探索水体中CODcr值与油类物质含量之间的相关性,对CODcr值准确性的判断有一定指导意义.改进含油废水的取样方法,有利于提高CODcr测定值的准确性和代表性.     

洱海地面水环境监测优化布点研究

根据１９８７年以后五年洱海水质监测数据的数理统计分析，选择污染指数大的ｐＨ、ＣＯＤ＿（Ｍｎ）、ＢＯＤ＿５、Ｔ－Ｎ、Ｔ－Ｐ进行单项方差分析，进而再进行灰色关联聚类分析和年际相关分析，确知洱海三个水质监测断面可归于一类。考虑水下地形、湖流、环湖工农业布局，水质监测点优化为两个即可保证其准确性、可控性和代表性。     

磷细菌筛选及其对苗期玉米生长的影响

从潮土、水稻土、砂姜黑土、石灰土上植物根际土壤和根中分离了86株磷细菌,通过NBRIP液体摇瓶培养3 d,培养液水溶磷质量浓度为4.2～387.3 mg.L^-1,水溶磷质量浓度与培养液pH呈显著负相关（r^2=0.621 6）。筛选出3株磷细菌进行玉米盆栽试验,结果表明,1株磷细菌处理的玉米干物质量和吸磷量与对照（处理4）相比无显著差异,2株磷细菌处理的玉米干物质量和吸磷量与对照相比有明显增加,干物质量增加了19.6%～37.5%,吸磷量增加了22.7%～40.2%,其中编号为HCW115解磷菌株的效果相当于施用无机磷（P）10 mg.kg^-1处理。     

Occurrence and migration of microplastics and plasticizers in different wastewater and sludge treatment units in municipal wastewater treatment plant

● Reduce the quantifying MPs time by using Nile red staining. ● The removal rate of MPs and PAEs in wastewater and sludge were investigated. ● MPs and PAEs were firstly analyzed during thermal hydrolysis treatment. ● The removal of PAEs from wastewater and sludge was mainly biodegradation. Microplastics (MPs) and plasticizers, such as phthalate esters (PAEs), were frequently detected in municipal wastewater treatment plants (MWTP). Previous research mainly studied the removal of MPs and PAEs in wastewater. However, the occurrence of MPs and PAEs in the sludge was generally ignored. To comprehensively investigate the occurrence and the migration behaviors of MPs and PAEs in MWTP, a series of representative parameters including the number, size, color, shape of MPs, and the concentrations of PAEs in wastewater and sludge were systematically investigated. In this study, the concentrations of MPs in the influent and effluent were 15.46±0.37 and 0.30±0.14 particles/L. The MP removal efficiency of 98.1% was achieved and about 73.8% of MPs were accumulated in the sludge in the MWTP. The numbers of MPs in the sludge before and after digestion were 4.40±0.14 and 0.31±0.01 particles/g (dry sludge), respectively. Fourier Transform Infrared Spectroscopy (ATR FT-IR) analysis showed that the main types of MPs were polyethylene terephthalate (PET), polypropylene (PP), polyethylene (PE), and polystyrene (PS). Six PAEs, including phthalate (DMP), diethyl phthalate (DEP), diisobutyl phthalate (DIBP), ortho dibutyl phthalate (DBP), butyl benzyl phthalate (BBP), and bis(2-ethyl) hexyl phthalate (DEHP), were detected in the MWTP. The concentrations of total PAEs (ΣPAEs) in the influent and effluent were 76.66 and 6.28 µg/L, respectively. The concentrations of ΣPAEs in the sludge before and after digestion were 152.64 and 31.70 µg/g, respectively. In the process of thermal hydrolysis, the number and size of MPs decreased accompanied by the increase of the plasticizer concentration.     

烟气脱硫过程锰催化氧化亚硫酸钙的研究

利用直径280 mm、高320 mm的间歇式搅拌槽,在MnSO4加入浓度为0～0.05 mol/L的情况下,对亚硫酸钙悬浮液进行了催化氧化实验研究.实验结果表明,锰离子的加入会改变亚硫酸钙的氧化机理及氧化过程,表现为终点氧化率和氧化速率的变化.当Mn2 浓度为0.05 mol/L时,亚硫酸钙的终点氧化率比未加入Mn2 时高30%;此外,与非催化反应过程相比,Mn2 的加入能使亚硫酸钙在一个更宽的浓度范围内(0.02～0.073 mol/L)和一个更宽的时间范围内(20～100 min)均保持较高的氧化速率水平.     

超声破解污泥上清液对A~2O工艺脱氮除磷和微生物群落结构的影响

为了提高传统污水处理工艺的脱氮除磷效率、实现污泥资源化,本实验通过超声破解污泥获取碳源,采用耗氧呼吸速率分析上清液作为碳源的可行性,并将上清液回用于生活污水,考察其对A2O工艺长期运行的脱氮除磷效果和微生物群落结构的影响。结果表明,上清液中可降解有机物达到76.2%,具有作为内碳源的潜能;上清液和生活污水按1∶15投入A2O反应器后,氮、磷的去除率分别从63.2%和53.4%提高到了82.1%和94.7%;上清液明显改变了微生物群落结构,使除磷菌Actinobacteia和反硝化聚磷菌Sphingobacterium富集。