长江三角洲城市群人为热排放特征研究

基于常规可获取的能源、交通、人口等统计资料,利用“自上而下”的能源清单法,研究了2010年长江三角洲(以下简称“长三角”)城市群地区各类人为热排放量及其时空分布特征.结果表明:该地区人为热排放总量为1.4′1019J/a,其中工业、交通、建筑、新陈代谢分别占75.1%、12.5%、9.9%和2.5%.上海、苏州、无锡、杭州和南京五个城市的人为热排放总量约占研究区域总量的71%.长三角城市群的人为热年平均排放通量为5.3W/m2,大部分地区介于5~30W/m2,城市高值区一般介于20~70W/m2,上海明显高于其他城市.为方便有关环境气候模式的输入,本文提供了人为热排放的网格化空间分布和简单的时间变化廓线.     

黏结剂对污泥基颗粒炭性能的影响

以城市污水处理厂剩余污泥为原料,可溶淀粉、羧甲基纤维素、硅酸钠和硫酸钙为黏结剂,采用两步炭化法制备污泥基颗粒炭,探讨了黏结剂种类对样品性能的影响.结果显示:可溶淀粉样品(SSGAC-T)具有最大的比表面积和孔容,SSGAC-T、羧甲基纤维素样品(SSGAC-C)和硅酸钠样品(SSGAC-Si)含有丰富的微孔和中孔,硫酸钙样品(SSGAC-S)为典型的中孔吸附剂;样品的抗压强度均随浸泡时间的延长而降低,但SSGAC-S的抗压强度下降程度最小;4种黏结剂都使样品表面生成新的官能团,且样品的表面均呈酸性,它们的pHPZC分别为6.37、6.16、5.85和5.53;相同条件下,SSGAC-S对亚甲基蓝的饱和吸附量最高,为71.94mg/g;根据对污泥炭的表征,初步推测硅酸钠和硫酸钙能与碳发生化学反应.     

中部3省城市建设用地功能时空演化特征

定量识别区域城市建设用地功能演化特征与模式,是推进可持续城市建设用地开发利用与管理、助力新型城镇化等国家战略的重要基础。从人口承载、生产与消费、公共服务3个方面构建了城市建设用地功能评价指标体系与模型,以地级市为研究单元探究了2000~2014年期间我国中部3省多尺度城市建设用地功能演化特征与模式。研究结果表明:(1)中部3省城市建设用地人口承载、生产与消费、公共服务和综合功能总体呈改善趋势,但演化过程复杂;(2)不同尺度尤其是城市群地区城市建设用地功能演化特征差异明显。沿长江和城市群地区城市建设用地功能演化强度高,但城市群地区空间异质性较强;(3)城市建设用地功能演化以复合型演化模式为主,演化格局复杂。其中,城市建设用地人口承载功能演化模式类型最多,且局部地区呈衰退型演化格局;城市建设用地生产与消费、公共服务功能和综合功能演化模式类型相对较少,且大多集中连片分布,武汉城市建设用地综合功能加速改善型演化特征显著。如何深入探究城市建设用地功能演化模式形成机理,并系统制定多级城市建设用地可持续利用管理策略,是实现我国新型城镇化和"美丽中国梦"等战略的重要任务。     

Antibiotic resistance genes in an urban river as impacted by bacterial community and physicochemical parameters

Antibiotic resistance genes (ARGs) in urban rivers are a serious public health concern in regions with poorly planned, rapid development. To gain insights into the predominant factors affecting the fate of ARGs in a highly polluted urban river in eastern China, a total of 285 ARGs, microbial communities, and 20 physicochemical parameters were analyzed for 17 sites. A total of 258 unique ARGs were detected using high-throughput qPCR, and the absolute abundance of total ARGs was positively correlated with total organic carbon and total dissolved nitrogen concentrations (P < 0.01). ARG abundance and diversity were greatly altered by microbial community structure. Variation partitioning analysis showed that the combined effects of multiple factors contributed to the profile and dissemination of ARGs, and variation of microbial communities was the major factor affecting the distribution of ARGs. The disparate distribution of some bacteria, including Bacteroides from mammalian gastrointestinal flora, Burkholderia from zoonotic infectious diseases, and Zoogloea from wastewater treatment, indicates that the urban river was strongly influenced by point-source pollution. Results imply that microbial community shifts caused by changes in water quality may lead to the spread of ARGs, and point-source pollution in urban rivers requires greater attention to control the transfer of ARGs between environmental bacteria and pathogens.

     

Flow diagram analysis of electrical fatalities in construction industry

The current study reanalyzed 250 electrical fatalities in the construction industry from 1996 to 2002 into seven patterns based on source of electricity (power line, energized equipment, improperly installed or damaged equipment), direct contact or indirect contact through some source of injury (boom vehicle, metal bar or pipe, and other conductive material). Each fatality was coded in terms of age, company size, experience, performing tasks, source of injury, accident cause and hazard pattern. The Chi-square Automatic Interaction Detector (CHAID) was applied to the coded data of the fatal electrocution to find a subset of predictors that might derive meaningful classifications or accident scenarios. A series of flow diagrams was constructed based on CHAID result to illustrate the flow of electricity traveling from electrical source to human body. Each of the flow diagrams can be directly linked with feasible prevention strategies by cutting the flow of electricity.     

基于热扩散管的深圳大气气溶胶半挥发性分析

在气溶胶质谱仪采样口前接入热扩散管,对深圳市2013年8月7日-9月7日大气细颗粒物进行连续在线观测,实现对气溶胶半挥发性的同步测定,量化其半挥发性水平.结果表明:加热温度为50℃时,约63%质量浓度的硝酸盐组分挥发至气相,是颗粒物中半挥发性最高的组分;而硫酸盐仍有约90%的颗粒残留,是半挥发性最低的组分;有机物的平均半挥发性高于硝酸盐,但低于硫酸盐.加热温度为200℃时,各组分的半挥发性接近,约有20%~30%的颗粒残留.在较为接近实际大气温度的50℃时,硝酸盐、有机物和硫酸盐的半挥发性因细颗粒物污染程度加剧而呈现不同的变化趋势.本文结果表明,深圳夏季大气细颗粒物具有显著的半挥发性,其大气环境影响值得今后深入研究.     

脉冲SBR工艺短程脱氮的实现及对除磷的强化

采用脉冲进水缺好氧交替工艺(SAOSBR)处理低C/N实际生活污水,考察了短程脱氮对于低碳源生活污水同步脱氮除磷效果的强化作用,并分析了短程脱氮强化生物除磷的机理.结果表明,通过短时的饥饿处理配合缺好氧交替的运行方式实现了系统的短程硝化,亚硝酸盐积累率稳定在95%以上.短程的实现还强化了系统的同步脱氮除磷效果,总氮和磷的平均去除率相比于全程脱氮过程分别提高了约6%和36%.分析表明短程强化生物除磷的原因主要是由于残留的NO2-对聚磷菌厌氧释磷的影响较小.静态试验也证实,在碳源不足的条件下,以NO2-为电子受体的反硝化作用相比于NO3-可以减弱反硝化菌与聚磷菌之间的碳源竞争,从而提高聚磷菌的厌氧释磷量和聚羟基烷酸(PHA)的合成量.因此,在处理低C/N生活污水时,短程脱氮的实现更有利于系统的生物除磷.     

Antagonism of phenanthrene cytotoxicity for human embryo lung fibroblast cell line HFL-I by green tea polyphenols

Polycyclic aromatic hydrocarbons (PAHs) have been detected in some commercial teas around the world and pose a threat to tea consumers. However, green tea polyphenols (GTP) possess remarkable antioxidant and anticancer effects. In this study, the potential of GTP to block the toxicity of the model PAH phenanthrene was examined in human embryo lung fibroblast cell line HFL-I. Both GTP and phenanthrene treatment individually caused dose-dependent inhibition of cell growth. A full factorial design experiment demonstrated that the interaction of phenanthrene and GTP significantly reduced growth inhibition. Using the median effect method showed that phenanthrene and GTP were antagonistic when the inhibitory levels were less than about 50%. Apoptosis and cell cycle detection suggested that only phenanthrene affected cell cycle significantly and caused cell death; GTP lowered the mortality of HFL-I cells exposed to phenanthrene; However, GTP did not affect modulation of the cell cycle by phenanthrene.     

邻苯二甲酸二异壬酯致小鼠肝组织氧化损伤的研究

研究邻苯二甲酸二异壬酯对小鼠肝细胞的氧化损伤.以昆明小鼠为受试动物,随机分为5组,包括1个阴性对照组、4个邻苯二甲酸二异壬酯染毒组,染毒组按0.5,5,50,500mg/kg4个剂量水平,灌胃染毒小鼠14d.以肝组织匀浆测定活性氧(ROS)、还原型谷胱甘肽(GSH)、丙二醛(MDA)和8-羟基脱氧鸟苷(8-OHdG)的含量;以肝组织细胞测定DNA-蛋白质交联(DPC)系数.随着邻苯二甲酸二异壬酯染毒剂量的升高,肝组织的ROS、MDA、8-OHdG含量和DPC系数逐渐上升,GSH含量逐渐降低,各指标呈一定的剂量-效应关系.染毒剂量为50mg/kg时, ROS、GSH、8-OHdG含量和DPC系数差异有统计学意义(P< 0.05, P< 0.01);染毒剂量为500mg/kg时,上述指标差异均有统计学(P< 0.05, P< 0.01).同时对小鼠肝组织形态进行光镜观察,结果表明,随着染毒剂量的加大,小鼠肝细胞的病理损伤越严重.较高剂量(350mg/kg)的邻苯二甲酸二异壬酯能造成小鼠肝组织的氧化损伤.     

长江三角洲城市群人为热排放特征研究

基于常规可获取的能源、交通、人口等统计资料,利用“自上而下”的能源清单法,研究了2010年长江三角洲(以下简称“长三角”)城市群地区各类人为热排放量及其时空分布特征.结果表明:该地区人为热排放总量为1.4′1019J/a,其中工业、交通、建筑、新陈代谢分别占75.1%、12.5%、9.9%和2.5%.上海、苏州、无锡、杭州和南京五个城市的人为热排放总量约占研究区域总量的71%.长三角城市群的人为热年平均排放通量为5.3W/m2,大部分地区介于5~30W/m2,城市高值区一般介于20~70W/m2,上海明显高于其他城市.为方便有关环境气候模式的输入,本文提供了人为热排放的网格化空间分布和简单的时间变化廓线.