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261.
本文利用三普、四普、五普和最新的人口抽样调查资料,运用历史分析法和对比分析法,首先对苏南地区20世纪80年代以来的人口增长、人口城市化、人口结构演变等进行了回顾,评述了人口发展在苏南经济高速增长中所发挥的重要作用,并总结了苏南地区人口发展中的新特征;然后,提出苏南人口发展现状对苏南地区未来的进一步提升发展可能造成的主要制约与矛盾;最后,从政策调控的角度,分区、分类提出了人口优化发展的措施。  相似文献   
262.
银行投资行为导致的环境破坏问题可能给银行带来环境风险。环境风险控制是实现我国金融可持续发展的必然选择。我国银行业环境风险控制体系由四部分组成,其中环境信息收集和传递是环境风险控制的基础,环境风险管理部门建设是环境风险控制业务的保障,环境风险动态评估和管理是环境风险控制的关键,借鉴国际经验和加入国际准则是提升环境风险控制水平的有效途径。本文通过对我国全国性商业银行在环境风险控制领域的举措进行分析,总结我国银行业环境风险控制体系构建的现状和问题。  相似文献   
263.
Many antibiotics regarded as emerging contaminants have been frequently detected in soils and groundwater; however, their transport behaviors in soils remain largely unknown. This study examined the transport of two antibiotics, sulfamethoxazole (SMZ) and ciprofloxacin (CIP), in saturated porous media. Laboratory columns packed with quartz sand was used to test the effects of solution pH and ionic strength (IS) on their retention and transport. The results showed that these two antibiotics behaved differently in the saturated sand columns. In general, SMZ manifested a much higher mobility than CIP for all experimental conditions tested. Almost all SMZ transported through the columns within one pore volume in deionized water (i.e., pH=5.6, IS=0), but no CIP was detected in the effluents under the same condition after extended column flushing. Perturbations in solution pH (5.6 and 9.5) and IS (0 and 0.1M) showed no effect on SMZ transport in the saturated columns. When pH increased to 9.5, however, ~93% of CIP was eluted from the sand columns. Increase of IS from 0 to 0.1M also slightly changed the distribution of adsorbed CIP within the sand column at pH 5.6, but still no CIP was detected in the effluents. A mathematical model based on advection-dispersion equation coupled with equilibrium and kinetic reactions successfully simulated the transport of the antibiotics in water-saturated porous media with R(2)=0.99.  相似文献   
264.
Thyroid hormone (TH) agonist and antagonist activities of water sources along the Yangtze River in China were surveyed by a green monkey kidney fibroblast (CV-1) cell-based TH reporter gene assay. Instrumental analysis was conducted to identify the responsible thyroid-active compounds. Instrumentally derived l-3,5,3′-triiodothyronine (T3) equivalents (T3-EQs) and thyroid receptor (TR) antagonist activity equivalents referring to dibutyl phthalate (DBP-EQs) were calculated from the concentrations of individual congeners. The reporter gene assay demonstrated that three out of eleven water sources contained TR agonist activity equivalents (TR-EQs), ranging from 286 to 293 ng T3/L. Anti-thyroid hormone activities were found in all water sources with the TR antagonist activity equivalents referring to DBP (Ant-TR-EQs), ranging from 51.5 to 555.3 μg/L. Comparisons of the equivalents from instrumental and biological assays suggested that high concentrations of DBP and di-2-ethylhexyl phthalate (DEHP) were responsible for the observed TR antagonist activities at some locations along the Yangtze River.  相似文献   
265.
研究沸石、胶质芽孢杆菌(Bacillus mucilaginosus)、黑曲霉(Aspergillus Niger)、胶质芽孢杆菌与沸石联合以及黑曲霉与沸石联合对模拟废水中Fe3+的吸附等温曲线,分析它们对Fe3+模拟废水的吸附及絮凝作用。结果表明:沸石对Fe3+吸附作用符合Freundlich方程;胶质芽孢杆菌分泌含...  相似文献   
266.
实验利用电沉积法制备的不锈钢基PbO2电极,以对氯苯酚溶液为模型废水,通过静态实验研究外加电压、电解质浓度、曝气量及初始pH值对电化学氧化降解对氯苯酚效果的影响。结果表明,实验制备的PbO2电极具有较高的电催化活性,能够有效降解对氯苯酚;较低的操作电压有助于降低处理成本;随着电解质浓度和曝气量的增加,对氯苯酚去除率均呈...  相似文献   
267.
采用厌氧滤池+HFBM工艺处理三羟甲基丙烷废水,在进水CODCr浓度小于10 000 mg.L-1、水力停留时间为96 h条件下,出水CODCr浓度稳定在500 mg.L-1以下,在进水中含0.5%甲醛条件下,经过7 d的冲击试验,出水CODCr浓度仍能保证在500 mg.L-1以下,中试试验直接运行费用为6.96元/t废水。  相似文献   
268.
Modern dairies cause the accumulation of considerable quantity of dairy manure which is a potential hazard to the environment. Dairy manure can also act as a principal larval resource for many insects such as the black soldier fly, Hermetia illucens. The black soldier fly larvae (BSFL) are considered as a new biotechnology to convert dairy manure into biodiesel and sugar. BSFL are a common colonizer of large variety of decomposing organic material in temperate and tropical areas. Adults do not need to be fed, except to take water, and acquired enough nutrition during larval development for reproduction. Dairy manure treated by BSFL is an economical way in animal facilities. Grease could be extracted from BSFL by petroleum ether, and then be treated with a two-step method to produce biodiesel. The digested dairy manure was hydrolyzed into sugar. In this study, approximately 1248.6 g fresh dairy manure was converted into 273.4 g dry residue by 1200 BSFL in 21 days. Approximately 15.8 g of biodiesel was gained from 70.8 g dry BSFL, and 96.2 g sugar was obtained from the digested dairy manure. The residual dry BSFL after grease extraction can be used as protein feedstuff.  相似文献   
269.
Fu  Li  Chen  Yi  Yang  Xinyi  Yang  Zuyao  Liu  Sha  Pei  Lei  Feng  Baixiang  Cao  Ganxiang  Liu  Xin  Lin  Hualiang  Li  Xing  Ye  Yufeng  Zhang  Bo  Sun  Jiufeng  Xu  Xiaojun  Liu  Tao  Ma  Wenjun 《Environmental science and pollution research international》2019,26(20):20137-20147
Environmental Science and Pollution Research - Fetal growth has been demonstrated to be an important predictor of perinatal and postnatal health. Although the effects of maternal exposure to air...  相似文献   
270.

The purposes of this research are to quantify the concentration of heavy metals (Zn, Cu, As, Pb, Cd, and Hg) in the water and fish tissues of common carp (Cyprinus carpio) in the upper Mekong River and to thereby elucidate the potential dietary health risks from fish consumption of local residents. Surface water and fish tissues (gill, muscle, liver, and intestine) from four representative sample areas (influence by a cascade of four dams) along the river were analyzed for heavy metal concentrations. Results revealed that the levels of heavy metals in fish were tissue-dependent. The highest Cu and As levels were found in the liver; the highest Zn and Pb levels occurred in the intestine, and the highest Hg level was found in the muscle. The total target hazard quotient (THQ) value for residents is > 1 for long-term fish consumption, and local residents are, therefore, exposed to a significant health risk. Results from the current study provide an overall understanding of the spatial and tissue distribution of heavy metals in water and fish body along the upper Mekong River under the influence of cascade dams and highlight the potential health risk of As for the local residents of long-term fish consumption.

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