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971.
我国环境技术转移模式与运行保障机制的研究   总被引:1,自引:0,他引:1  
全面阐述了我国环境技术成果转化推广机制建设取得的积极进展,以及当前存在的困难和问题;基于环境技术转移体制机制的内涵,提出了环境技术转化转移机制建设应遵循的四项原则;论述了环境技术转化转移模式选择和六项保障环境技术转化转移能动健康运行的保障机制性措施。  相似文献   
972.
以四川藏区农村的环境公害问题为引入对象,结合先进国家和地区的农村生态环境法制管理救济机制和应对机制,从现行相关程序法和实体法的法理角度,初步阐释适合我国农村生态环境法制实现的救济处理机制和救济途径,从而在一定程序上构建起我国的环境救济法体系。  相似文献   
973.
The chemical composition of persistent organic pollutants (POPs) in the environment is not uniform throughout the world, and these contaminants contain many structurally different lipophilic compounds. In a well-defined study cohort in the Slovak Republic, the POP chemicals present in the peripheral blood of exposed children were chemically analyzed. The chemical analysis data revealed that the relative concentration and profile of structurally different organic pollutants, including polychlorinated biphenyls (PCBs), 2,2′-bis(4-chlorophenyl)-1,1-dichloroethylene (p,p′-DDE), 2,2′-bis(4-chlorophenyl)-1,1,1-trichloro-ethane (p,p′-DDT), hexachlorobenzene (HCB) and β-hexachlorocyclohexane (β-HCH), may vary from individual to individual, even within the same exposure area. These chemicals can be broadly classified into two groups. The first group, the PCB congeners, primarily originated from industrial compounds and their byproducts. The second group of compounds originated from or was commonly used in the agricultural sector (e.g., DDT, HCB). The objective of this study was to examine the effects of the two POP exposure profiles on gene expression. For the study population, we selected pre-pubertal girls (mean age of 46.2 ± 1.4 months) with high POP concentrations in their blood (> 75% tile of total POP) and classified them in the high ‘PCB’ group when the total PCB concentration was significantly higher than the total concentration of other POP components and in the ‘Other Than PCB’ (OTP) group, when the total PCB concentration was significantly lower than the concentration of the other major POP constituents. A matched control group of girls (< 25% tile of total POP) was selected for comparison purpose (n = 5 per group). Our aims were to determine whether there were any common effects of high POP exposure at a toxicogenomic level and to investigate how exposure may affect physiological functions of the children in two different exposure scenarios. Global gene expression analysis using a microarray (Affymetrix Gene Chip Human genome U133 Plus 2.0 Array) platform was conducted on the total RNA of peripheral blood mononuclear cells from the girls. The results were analyzed by Partek GS, Louis, MI, which identified twelve genes (ATAD2B, BIVM, CD96, CXorf39, CYTH1 ETNK1, FAM13A, HIRA, INO80B, ODG1, RAD23B, and TSGA14) and two unidentified probe sets, as regulated differentially in both the PCB and OTP groups against the control group. The qRT-PCR method was used to validate the microarray results. The Ingenuity Pathway Analysis (IPA) software package identified the possible molecular impairments and disease risks associated with each gene set. Connective tissue disorders, genetic disorders, skeletal muscular disorders and neurological diseases were associated with the 12 common genes. The data therefore identified the potential molecular effects of POP exposure on a genomic level. This report underscores the importance of further study to validate the results in a random population and to evaluate the use of the identified genes as biomarkers for POP exposure.  相似文献   
974.
采用化学共沉淀法合成磁性海泡石,通过静态吸附实验研究磁性海泡石对Cr(Ⅵ)的吸附特性及其动力学。结果表明,磁性海泡石对Cr(Ⅵ)的吸附在90 min内即可达到平衡;体系的初始pH是影响磁性海泡石吸附Cr(Ⅵ)性能的重要因素;当废水中Cr(Ⅵ)的初始浓度为50 mg/L时,磁性海泡石的适宜投加量为10 g/L;随反应温度的升高,磁性海泡石对Cr(Ⅵ)的吸附量增加;温度为25、35和45℃时,磁性海泡石对Cr(Ⅵ)的饱和吸附量分别为3.32、3.72、4.08 mg/g;吸附动力学曲线可以用拟二级反应动力学模型拟合;内扩散和液膜扩散联合控制Cr(Ⅵ)在磁性海泡石上的吸附过程,其中内扩散的控速作用大于液膜扩散。  相似文献   
975.
结合大连的开发区时间,从集聚和引力扩散、制度创新、跨国公司主导下的产业链式成长、对母城的有机疏散、产业空间优化与重组、行政区划调整等6个方面探讨了开发区城市化效应的作用机制.在此基础上,总结了开发区城市化的3种空间模式,即大型综合经济功能区的飞地型模式、大型高新技术园区的郊区化模式、中小园区组群发展的嵌入与填充模式,提出了优化开发区城市化效应的对策建议.  相似文献   
976.
王学恭  白洁  赵世明 《资源开发与市场》2012,(12):1093-1095,1077
生态补偿标准是建立有效草地生态补偿机制的核心问题。以草原生态保护补助奖励机制为例,从禁牧补偿额度、草畜均衡补偿额度、生态补偿的均衡性等方面分析了草地生态补偿标准的空间尺度差异。结果表明,虽然当前草地生态补偿的标准空间差异明显,但并没有反映出不同空间尺度草地生态系统服务功能的分异。  相似文献   
977.
介绍了目前我国城镇污水处理厂的发展现状以及将其作为污染源纳入监管的背景;从进水水质监管、出水水质监管和对污水处理厂内部运营管理监管的角度,结合对部分地区行政管理部门、污水处理厂的调研,分析了污水处理厂出水水质不达标的主要原因;针对我国的实际情况并借鉴国外经验,从政府部门的监管职能、政企的合作、监管技术和末端污染控制方面,给出了加强污水处理厂运行监管效果的对策。  相似文献   
978.
锦标机制理论下企业低碳经济发展激励机制研究   总被引:1,自引:0,他引:1  
按照企业发展与环境相容的原则,低碳经济是应对全球变暖的最佳经济模式,低碳经济以低能耗、低排放、低污染为基本特征,以应对碳基能源对于气候变暖影响为基本要求,以实现经济社会的可持续发展为基本目的.鉴于当前文献关于企业发展低碳经济的激励机制研究还略显不足,文章借鉴激励理论中的委托代理理论,根据Malcomson模型的研究方法,构建了包括1阶段合约和2阶段合约的企业发展低碳经济的激励机制框架,设立基于相对业绩的"锦标机制"模型并对模型进行系统分析,推导出政府在制定企业发展低碳经济激励政策时的注意事项,即中央政府要加大财政转移支付力度,支持地方发展低碳经济;地方政府要设立专门的低碳经济发展激励基金,并纳入财政预算管理;地方政府在激励企业发展低碳经济时,要有层次、有针对的对企业给予政策支持或财政补贴,形成阶梯式的支持结构,使有限财政资金得到合理配置;地方政府应该以区域内企业实施低碳经济活动的努力水平为评判标准对企业进行激励.  相似文献   
979.
The study presented the concentrations and distributions of polybrominated dibenzo-p-dioxins and polybrominated dibenzofurans (PBDD/Fs) as impurities in some commercial decabromodiphenyl ether (DBDE) mixtures that were produced by several manufacturers. The total concentrations of 12 2,3,7,8-substituted tetra- to octa-BDD/F congeners were found to be in the range of 3.4-13.6 (mean 7.8) μg/g, averagely accounting for 99% of total PBDD/Fs. OBDF was the prevailing congener, followed by 1,2,3,4,6,7,8-HpBDF. In addition, OBDD and 1,2,3,4,7,8-HxBDF were also obviously detectable. The total concentrations of PBDD/Fs varied both between the manufacturers and between the lots. On the basis of the global demand for the commercial DBDE in 2001, the annual potential emissions of PBDD/Fs were calculated coarsely to be 0.43 (range: 0.21-0.78) tons. The major dioxin congeners, OBDF and 1,2,3,4,6,7,8-HpBDF, presenting in DBDE, were estimated to be formed from BDE-209, BDE-206, and/or BDE-207 via an intra-molecular elimination of Br2/HBr.  相似文献   
980.
The environmental risks of antibiotics have attracted lots of research attention, but their environmental behavior is not clear yet. Functionalized carbon nanotubes (CNTs) were used as model adsorbents and sulfamethoxazole (SMX) was used as a model antibiotic to investigate the effect of both cations (Ca2+, Cs+) and anions (phosphate) on antibiotics adsorption. Various mechanisms (such as electrostatic interaction, hydrophobic interaction, π-π and hydrogen bonds) play roles in SMX adsorption. Cations and anions could “wedge into” these mechanisms and thus alter SMX adsorption. This study emphasized that both increased and decreased SMX adsorption could be observed with the addition of cations/anions, depending on environmental conditions (such as pH in this current study). The net effect is the balance between the increased and decreased effects. The contribution of different mechanisms to the overall antibiotic adsorption on solid particles should be identified to accurately predict the apparent effect by cations and anions.  相似文献   
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