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551.
在宜昌环境总体规划(2013-2030)得到市人大批复实施的背景下,为共享环境总体规划生态功能红线、环境质量红线与资源开发红线("三条红线")、为满足提供规划实施与评估有效途径的实际需求,在市信息办及环保局现有业务信息系统现状评价基础上,综合运用GIS、海量空间数据管理、SOA架构、瓦片地图分发、移动GIS等技术,设计开发了宜昌市环境总体规划信息管理与应用系统(V1.0),实现了"三条红线"等相关数据成果的地图展示、查询等精确管理分析以及项目环境影响评价的辅助决策.  相似文献   
552.
水解是农药在环境中降解的一条重要途径。为正确评价农药在各种环境条件下的残留行为,有必要系统地研究温度和介质酸碱度对农药水解速率的影响。  相似文献   
553.
论中国环境保护公众参与制度的建设   总被引:1,自引:0,他引:1  
公众参与是环境保护最有力的支持之一,是解决中国环境问题的重要途径,公众参与环境保护的程度,直接体现着一个国家环境意识、生态文明的发育程度,体现着一个国家可持续发展的水平.从公众参与的内涵及法律依据着手,说明环境保护中公众参与的必要性,并分析目前中国公众参与的现状:虽然环保已成为公众关注的社会热点,但公众参与环境保护的程度还很低.通过分析其原因,指出只有建立健全环保公众参与制度,实现有效的公众参与才是推动环保可持续发展的根本力量所在.  相似文献   
554.
● Synergistic removal of carbamazepine (CBZ) was obtained in the FeS-S2O82– process. ● SO4•− and •OH were identified as the main radicals in the FeS-S2O82– process. ● Heterogeneous oxidation would be dominant first, followed by homogeneous reaction. ● Degradation pathway of CBZ was well elucidated by experiments and DFT calculations. As persulfate (S2O82–) is being increasingly used as an alternative oxidizing agent, developing low-cost and eco-friendly catalysts for efficient S2O82– activation is potentially useful for the treatment of wastewater containing refractory organic pollutant. In this study, the degradative features and mechanisms of carbamazepine (CBZ) were systematically investigated in a novel FeS- S2O82– process under near-neutral conditions. The results exhibited that CBZ can be effectively eliminated by the FeS-S2O82– process and the optimal conditions were: 250 mg/L FeS, 0.5 mmol/L S2O82–, and pH = 6.0. The existence of Cl (1 and 50 mmol/L) has little influence on the CBZ elimination, while both HCO3 and HPO42− (1 and 50 mmol/L) significantly suppressed the CBZ removal in the FeS-S2O82– process. CBZ could be degraded via a radical mechanism in the FeS-S2O82– process, the working radical species (i.e., SO4•− and •OH) were efficiently formed via the promoted decomposition of S2O82– by the surface Fe2+ on the FeS and the dissolved ferrous ions in solution. Based on the identified oxidized products and Fukui index calculations, a possible degradation pathway of CBZ was speculated. More importantly, a two-stage oxidation mechanism of CBZ elimination was speculated in the FeS-S2O82– process, the activation of S2O82– by the surface-active Fe(II) of FeS dominated in the initial 5 min, while homogeneous oxidation reactions played more essential parts than others in the following reaction stage (5–60 min). Overall, this study demonstrated that the FeS-S2O82– process is capable of removing CBZ from water efficiently.  相似文献   
555.
文章研究了用Fe(NO3)3NaOH改性的活性炭联合过氧化氢对水溶液中氨苄青霉素钠的处理效果.确定了它们的优化处理条件,并对两者的处理效果作了相应比较。在T=30℃,pH:3.0,青霉素初始浓度为200mg/L条件下,投加5.0g/LFe(N03)3改性活性炭和80mg/LH202,反应120min后,COD、TOC去除率分别可以达到88.5%和77.9%;在T=30℃,pH=70,青霉素200mg/L条件下,投加8.0g/LNaOH改性活性炭和80mg/LH202,反应120rain后,COD、TOC去除率分别可以达到85.2%和76.4%。  相似文献   
556.
液膜法去除水中Cr(Ⅵ)的研究   总被引:2,自引:0,他引:2  
本文采用液膜法去除并回收水中Cr(Ⅵ)。对膜溶剂、载体、稳定剂的种类及用量进行了优选。用优选出的膜配方制成乳液处理含Cr(Ⅵ)水样,对制膜速度及时间、混合速度及时间、内外水相pH、膜内比及乳水比等操作条件对Cr(Ⅵ)去除率的影响进行了研究。  相似文献   
557.
Increasing soil carbon (C) storage is crucial to addressing climate change and ensuring food security. The C sequestration potential of the world’s cropland soil is 0.4–0.8 Pg soil C year?1, which may be achieved through the adoption of recommended management practices (RMPs), including fertilizer management. This study aimed to quantitatively evaluate the influence of long-term application of different fertilizers and straw retention on soil organic carbon (SOC) storage, to compare the calculated response ratios with Intergovernmental Panel on Climate Change (IPCC)-recommended default relative stock change factors, and to propose recommendations for enhancing SOC sequestration. The meta-analysis indicated that the long-term application of chemical fertilizers (CF), organic fertilizers (OF), combined chemical and organic fertilizers (CFOF), and straw return (SR) significantly enhanced the SOC storage. Response ratios varied significantly (p < 0.05) across different fertilization measures and climatic zones, and was sensitive to the initial SOC content. The mean response ratio was 0.94 for no fertilizer (NF), 1.08 for CF, 1.48 for OF, 1.38 for CFOF, and 1.28 for SR. When IPCC default values for response ratios were applied, SOC storage with OF and CFOF treatments in warm temperate regions with a dry climate was underestimated by 26%, and in the cool temperate region with a moist climate was overestimated by 25% (p < 0.05). Analysis showed that sustained application of organic fertilizers and straw return could be a beneficial measures to mitigate climate change and ensure food security in China. Our findings highlight the importance of deriving SOC stock change factors for a detailed classification of cropland by fertilizer management, climate, and soil types in order to more accurately reflect the effects of policy measures.  相似文献   
558.
Diagnostic ratios and multivariate analysis were utilized to apportion polycyclic aromatic hydrocarbon (PAH) sources for road runoff, road dust, rain and canopy throughfall based on samples collected in an urban area of Beijing, China. Three sampling sites representing vehicle lane, bicycle lane and branch road were selected. For road runoff and road dust, vehicular emission and coal combustion were identified as major sources, and the source contributions varied among the sampling sites. For rain, three principal components were apportioned representing coal/oil combustion (54%), vehicular emission (34%) and coking (12%). For canopy throughfall, vehicular emission (56%), coal combustion (30%) and oil combustion (14%) were identified as major sources. Overall, the PAH's source for road runoff mainly reflected that for road dust. Despite site-specific sources, the findings at the study area provided a general picture of PAHs sources for the road runoff system in urban area of Beijing.  相似文献   
559.
构建科学合理的基准价定价机制是推动排污权交易的基础性工作,本文以政策、管理、技术三个方面作为立足点,探讨了基准价定价机制,构建了工作框架。研究认为现阶段基准价定价采取成本定价法是合适的,并对基准价定价技术难点进行了剖析,提出了建议。  相似文献   
560.
<正>高温季节,企业工会通常会为生产一线职工送去各种清凉饮料,但多数职工认为这仅是表面工作,应景行为,工会应从根本上关心职工的劳动保护工作。  相似文献   
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