活性炭处理甲苯气体吸附再生实验研究

研究了活性炭对甲苯废气的吸附穿透过程及热空气解吸过程.穿透曲线实验结果表明,在常规空塔气速范围内,传质区高度基本在5.06～9.75 cm,传质区不饱和度在0.4～0.7.在动态运行情况下,活性炭对甲苯的饱和吸附容量在0.16～0.24 g/g.热空气吹脱实验表明,适宜的脱附工况条件为脱附温度180 ℃、脱附空气流速0.106 m/s、脱附时间40 min.     

苯酚羟化酶基因工程菌表达优化及特性研究

利用表面响应法优化苯酚羟化酶基因工程菌(PH_IND)的生长条件(种龄、接种量)及表达条件(诱导OD600、IPTG浓度、诱导时间、诱导温度),并对其粗酶特性进行考察.实验结果表明,菌株PH_IND的最佳生长条件及表达条件为:种龄7.19h,接种量1.39%,诱导OD6000.54,IPTG浓度0.19mmol·L-1,诱导时间2.37h,诱导温度35℃,此时,苯酚羟化酶最大酶活力为0.6167U·mg-1.粗酶特性分析表明,苯酚羟化酶的最适pH和温度分别为8.0和40℃.Ba2+、Fe3+、Hg2+、Pb2+对苯酚羟化酶有明显促进作用,而Ca2+、Co2+、Cu2+、Mg2+、Mn2+对苯酚羟化酶有抑制作用.底物广谱性实验表明,苯酚羟化酶具有极强的芳香化合物降解能力.     

黑麦草对土壤中残留抗生素的降解及其对微生物活性的影响

为了研究抗生素污染土壤的修复方法,利用黑麦草对土壤中残留抗生素进行降解,并探讨土壤微生物生态活性及根系体表特征的响应。结果表明：黑麦草对土壤中四环素、金霉素、恩诺沙星、洛美沙星、环丙沙星、诺氟沙星的降解速率均显著大于对照（pr=-0.948,p<0.05）。     

天津《大气污染防治行动计划》实施减排效益

为定量评估天津市《大气污染防治行动计划》实施的减排效益,研究依据大气污染源排放清单编制技术指南,通过梳理2013-2017年活动水平数据,分析主要防治措施的逐年减排效益,以期为大气环境管理政策决策提供重要参考。结果显示,2013-2017年天津市采取的主要防治措施对PM_2.5的累计减排量为5.7万t,减排比例为52.5%;对PM10的累计减排量为10.6万t,减排比例为53.6%;对SO₂的累计减排量为11.7万t,减排比例为75.2%;对NOx的累计减排量为17.8万t,减排比例为48.8%;对CO的累计减排量为65.3万t,减排比例为44.9%;对VOCs的累计减排量为7.0万t,减排比例为36.6%。PM_2.5的减排主要得益于工艺污染的防治,其次是工业锅炉的防治;PM10的减排主要得益于扬尘源的防治,其次是工艺污染的防治;SO₂的减排主要得益于工业锅炉的防治,其次是供暖锅炉的防治;NOx的减排主要得益于工业锅炉的防治,其次是供暖锅炉的防治;CO的减排主要得益于工业锅炉的防治,其次是工艺污染的防...     

精轧工艺颗粒物污染特征及其岗位环境浓度监测

为探究我国钢铁行业热轧厂精轧工艺的污染特征,利用扫描电镜(SEM)和激光粒度分布测定实验以及现场实测,于2019年夏季对广东省某典型热轧厂精轧工艺颗粒物进行微观形貌、粒径分布及其岗位环境污染规律研究。结果表明,精轧工艺所产颗粒物外观呈不规则块状形态,粒径集中在2.423~3.519 μm,其Rosin-Rammler粒径分布函数的均匀度指数为1.769,特征尺寸为2.932 μm。该结果为精轧工艺进行净化除尘数值模拟分析奠定了基础;其岗位环境颗粒物浓度随时间呈周期性波动变化,精轧区测点浓度沿轧制方向逐架递增,PM_2.5/PM₁₀均值比例依次为0.807、0.749、0.912,侧面反映了精轧源的污染特性。在精轧区排风罩设计中,建议沿轧制方向,每架精轧机排风罩的设计风量依次增大,达到精准控制局部环境的效果。     

Neglected skin-associated microbial communities: a unique immune defense strategy of Bufo raddei under environmental heavy metal pollution

Environmental Science and Pollution Research - Amphibians defend against pathogens using skin microbial communities, in addition to innate and adaptive immunity. Despite skin microbial communities...     

Modelling the thresholds of nitrogen/phosphorus concentration and hydraulic retention time for bloom control in reclaimed water landscape

● A new model for bloom control in open land scape water was constructed. ● It considers the effects of temperature and light on algae growth. ● It describes threshold curve of nitrogen, phosp horus and hydraulic retention time. ● Light and temperature dependent growth para meters of typical algae were obtained. The risks posed by algal blooms caused by nitrogen and phosphorus in reclaimed water used in urban water landscapes need to be carefully controlled. In this study, the combined effects of the nitrogen and phosphorus concentrations and the light intensity and temperature on the specific growth rates of algae were determined using Monod, Steele, and Arrhenius models, then an integrated algal growth model was developed. The algae biomass, nitrogen concentration, and phosphorus concentration mass balance equations were used to establish a new control model describing the nitrogen and phosphorus concentration and hydraulic retention time thresholds for algal blooms. The model parameters were determined by fitting the models to data acquired experimentally. Finally, the control model and numerical simulations for six typical algae and mixed algae under standard conditions were used to determine nitrogen/phosphorus concentration and hydraulic retention time thresholds for landscape water to which reclaimed water is supplied (i.e., for a reclaimed water landscape).     

职业健康多维共建防治体系模型的研究

为改善我国目前严峻的职业健康现状,通过分析职业健康防治体系存在的主要问题,提出多维共建防治理念,运用层次分析法从政府、用人单位和劳动者三种维度出发,建立职业健康多维共建防治体系,包括政府、用人单位、员工3个一级指标和下属的23个二级指标,采用综合指数法构建职业健康评价模型。     

Luoyang Dual Spatial Criterion Ecological City Construction

Abstract

The construction of an ecological city has two foundational platforms: the small platform, namely urban district or simply called as “city ecosystem”; and the big platform, namely around city district in certain region scope or also referred to as “city-region ecosystem”. The construction of an ecological city must be launched in the dual spatial criteria: in city (urban district) criterion—optimizing the city ecosystem; in city-region (city territory) criterion—optimizing the city-region ecosystem. Luoyang has the bright characteristic and the typical image within cities of China, and even in the world. The construction of an ecological city in dual spatial criteria—the city and the city-region—has the vital significance to urbanization advancement and sustainable development in Luoyang. In city-region criterion, the primary mission of Luoyang's ecological city construction is to create a fine ecological environment platform in its city territory. In city criterion, the basic duty of Luoyang's ecologic city construction is to enhance the ecological capacity and benefit of the central city.     

基于CEEMDAN的多时间尺度的北京市PM2.5浓度影响因素研究

研究PM_2.5浓度的主要影响因素,对提升北京市空气质量具有重要意义。与以往仅限于原始时间尺度的研究不同,本文基于CEEMDAN方法考察了多时间尺度下年平均风速、城市绿化、人口密度、产业结构和能源强度对北京市PM_2.5浓度波动的影响,并与原始时间尺度的主导因素进行对比。研究发现：原始尺度的北京市PM_2.5浓度影响因素是不同时间尺度内影响因素合力作用结果,不同时间尺度下影响因素不同。城市绿化、人口密度、产业结构和能源强度在多时间尺度中起到短期增强波动的作用,城市绿化和产业结构是贯穿于各个时间尺度的具有趋势性,决定北京市PM_2.5浓度基本走势的影响因素。