小型砂滤池在废水处理中的应用

本文通过湿式除尘后的废水治理及工程实例,探讨了小型砂滤池在废水处 理中应用的可行性。     

民国初年北洋政府救灾举措述评

学界有一种观点认为,民初北洋政府漠视救灾,事实并非如此。本文例举了当时内务部等政府部门在救灾方面的措施,其大致可分为消极式的治标举措和积极式的治本举措。其中治标举措包括赈济、调粟、养恤、除害、资遣、蠲缓、放贷类灾后补救办法,积极式的治本举措包括重农、仓储、水利和林垦等。各重治标措施和治本措施的同时并举,显现了民初北洋政府对救灾的重视,学界那种认为政府漠视救灾的观点,值得商榷。     

昆明城市生活垃圾处理产业发展的SWOT分析研究

随着城市化进程的深入,生活垃圾问题日益突出,城市生活垃圾处理产业的发展是解决“垃圾围城”困境的有效途径.昆明城市生活垃圾处理产业处于发展阶段,运用态势分析法(SWOT),系统地对昆明城市生活垃圾处理产业发展的优势、劣势、所存在的机会和威胁进行分析,并提出相应发展对策,包括完善生活垃圾处理.产业的经济激励机制;采用多种项目融资模式进行生活垃圾产业建设融资;加快静脉产业园区建设发展;打造再生资源回收利用的龙头企业;积极控制生活垃圾源头;建立垃圾排放权交易等.     

沈阳市冬季一次严重污染天气过程成因分析

为探讨沈阳市冬季重污染天气的初步成因。以2013年1月11日~16日沈阳市发生的一次严重污染天气为例,利用中国气象局的MICAPS系统和美国的HYSPLT模式,从污染形成的天气背景、污染物扩散受地形的影响情况以及外来污染物输送的气流轨迹等几方面综合分析,从而探讨此次严重污染过程的成因:长白山小高压和西部倒槽双重系统的控制下,地面吹东北风,风速较小,湿度大,不利于污染物的水平扩散;有较强接地逆温存在时,不利于污染物的垂直扩散,导致近地面污染物累积;受来自于北部和东北部低层气流的影响,将内蒙古、辽宁东北部的污染物携带到沈阳地区汇聚。     

基于随机模拟与三角模糊数耦合模型的地下水环境健康风险评价研究

水环境健康风险评价在参数确定、暴露评估与风险表征过程中存在着不确定性因素,利用随机模拟与三角模糊数耦合模型（SS-TFN模型）进行水环境健康风险评价,降低了评价过程中人为因素的影响,有效提高评价结果的可靠性和科学性.本文将SS-TFN模型应用于盘锦市六个饮用水源地致癌物质经饮水途径的地下水环境健康风险评价中,结果表明：盘锦市六个饮用水源地的总致癌风险均超过致癌年风险率控制限值（1.0＆#215;10-5）;致癌物质造成的平均个人致癌年风险率由高到低排序：Cr6＋＞ As＞ Cd.盘锦市六个饮用水源地SS-TFN计算结果收敛时总的平均个人致癌年风险由高到低排列：大洼水源＞兴南水源＞兴一水源＞盘东水源＞高升水源＞石山水源.     

台州市经济增长与环境污染关系分析研究

环境库兹涅茨曲线(Environmental Kuznets Curve,简称EKC),常用来描述经济增长与环境质量之间的关系,传统的环境库兹涅茨曲线一般具有倒"U"形特征。通过对1990年-2010年台州市环境数据和经济数据的计量模型研究,发现台州市排放的污染物环境库兹涅茨曲线不完全符合传统的环境库兹涅茨曲线特征,并对这一结果进行了深入分析。环境质量的改善并不是随着人均GDP的增长而自动发生。除了经济收入这个因素外,影响环境质量的因素还有很多,如种族构成、公民受教育程度、集体行动的倾向性、人口密度等等。经过研究得出结论:台州市总体环境状况有着进一步恶化的趋势,应该加大环保力度,提倡清洁生产和"三废"循环利用,使经济增长与环境状况同时向着有利于人类的方向发展,实现可持续发展。     

Assessment of the sources and transformations of nitrogen in a plain river network region using a stable isotope approach

The great spatial and temporal variability in hydrological conditions and nitrogen(N)processing introduces large uncertainties to the identification of N sources and quantifying N cycles in plain river network regions. By combining isotopic data with chemical and hydrologic measurements, we determined the relative importance of N sources and biogeochemical N processes in the Taige River in the East Plain Region of China. The river was polluted more seriously by anthropogenic inputs in winter than in summer. Manure and urban sewage effluent were the main nitrate(NO-3) sources, with the nitrification of N-containing organic materials serving as another important source of NO-3. In the downstream, with minor variations in hydrological conditions, nitrification played a more important role than assimilation for the decreasing ammonium(NH+4-N) concentrations.The N isotopic enrichment factors(ε) during NH+4utilization ranged from- 13.88‰ in March to- 29.00‰ in July. The ratio of the increase in δ18O and δ15N of river NO-3in the downstream was 1.04 in January and 0.92 in March. This ratio indicated that NO-3assimilation by phytoplankton was responsible for the increasing δ15N and δ18O values of NO-3in winter. The relationships between δ15N of particulate organic nitrogen and isotopic compositions of dissolved inorganic nitrogen indicated that the phytoplankton in the Taige River probably utilized NH+4preferentially and mainly in summer, while in winter, NO-3assimilation by phytoplankton was dominant.     

Zero-valent iron doped carbons readily developed from sewage sludge for lead removal from aqueous solution

Low-cost but high-efficiency composites of iron-containing porous carbons were prepared using sewage sludge and ferric salts as raw materials. Unlike previous time- and energy-consuming manufacturing procedures, this study shows that pyrolyzing a mixture of sludge and ferric salt can produce suitable composites for lead adsorption. The specific surface area, the total pore volume and the average pore width of the optimal composite were 321 m²/g, 0.25 cm³/g, and 3.17 nm, respectively. X-ray diffraction analysis indicated that ferric salt favored the formation of metallic iron, while Fourier transform infrared spectroscopy revealed the formation of hydroxyl and carboxylic groups. The result of batch tests indicated that the adsorption capacity of carbons activated with ferric salt could be as high as 128.9 mg/g, while that of carbons without activation was 79.1 mg/g. The new manufacturing procedure used in this study could save at least 19.5 kJ of energy per gram of activated carbon.     

食蚊鱼(Gambusia afinis)cat、gapdh和gst基因的克隆及其在生态毒理学中的应用

根据Ensembl、Genbank登录的鱼类cat、gapdh和gst基因的CDS序列设计普通PCR扩增引物,寻找食蚊鱼的cat、gapdh和gst基因的c DNA片段,并根据定量引物设计要求设计出相应的SYBR Green I荧光定量RT-q PCR引物,建立了食蚊鱼cat、gapdh和gst基因的SYBR Green I荧光定量RT-q PCR方法。该方法在104~108数量级范围内有良好线性关系(R=0.999~1.000);熔解曲线显示扩增产物特异性良好,均为单一峰值;质粒标准品最高浓度与最低浓度的批内试验变异系数与批间试验变异系数均低于2%。利用该方法监测和评价环境污染物对水生生物的影响,选择了水体中常见典型药物污染物——双氯芬酸,研究其对食蚊鱼抗氧化基因表达的影响。结果表明,雌性食蚊鱼暴露在不同浓度双氯芬酸钠(0.005、0.05、0.5和5 mg·L-1)24 h后,其肝脏cat、gapdh和gst的mRNA呈现显著变化,相对于对照组,在低浓度0.005 mg·L-1时,cat与gst mRNA的表达量均有极显著上升(p0.01),而其它浓度均极显著下降(p0.01)。试验表明该方法具有快速、精确、灵敏度高的优点,可为利用该类小型鱼类的原位污染物的生物监测和生态毒理评价提供有力的技术支持。