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生物质常被添加至富营养水体中以调节碳氮比(C/N),促进脱氮,但不清楚生物质的粒径和投加方式对富营养水体中营养物质浓度和比例的影响。通过机械粉碎制得20~40、40~80、80~160目稻壳颗粒,并选取直接投加和无纺布包裹投加2种投加形式,以不添加稻壳或无纺布包裹砖块作为对照组。以超纯水为水样研究不同粒径和投加方式下稻壳的3 d碳氮磷释放特性;以成都市府河下游河段水样为研究对象,考察了不同粒径和投加方式下稻壳的21 d静态脱氮特性。结果表明,在超纯水中,稻壳释放出CODMn(5.5~16.5 mg·L−1)、TP(0.18~0.45 mg·L−1)、TN(0.39~0.95 mg·L−1)、CODMn/TN(8.5~19.7)、CODMn/TP(27.9~37.5),前四者均呈现出80~160目>40~80目>20~40目的规律,仅CODMn和CODMn/TN呈现直接投加>无纺布包裹投加的规律。在静态脱氮实验中,21 d后,添加了稻壳的水样CODMn含量由28.1 mg上升至71.7~143.0 mg,TP含量由1.2 mg下降至0.2~0.5 mg,CODMn/TN由0.9上升至8.5~16.5,CODMn/TP由24.2上升至170以上,这4个参数的变化情况与稻壳的碳氮磷释放规律相同;TN含量由30.04 mg下降至7.64~8.68 mg,低于对照组(13.2~13.9 mg),但粒径和投加方式仅对实验初期水中氮的存在形态有影响。粒径决定稻壳的比表面积,投加方式决定稻壳的间隙,并影响微生物的附着效果,进而影响稻壳的碳氮磷释放效果。在实际应用时可根据情况,采用不同的生物质粒径和投加方式,以调节水中营养物质浓度和比例。  相似文献   
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Environment, Development and Sustainability - Ecological civilization is an advanced form after industrial civilization. Improving China's ecological civilization system will provide developing...  相似文献   
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Environment, Development and Sustainability - This study aims to determine the impact of financial development on green ecology to promote cleaner production. Particularly, it estimates the...  相似文献   
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张怡  刘本洪  刘蕾  杨春 《环境工程学报》2021,15(12):3875-3882
将富营养水体治理与硬质河岸改造相结合,能够提高水体与河岸的交互能力,恢复河流生态系统的自净能力.以位于四川省天府新区眉山片区中心城区的柴桑河河段(长度1.5km,宽度80~100m,水深约1.85m)为例,通过铺设护岸专用基料、设置滴灌系统和播撒花草种子对硬质河岸进行生态重建,通过向水体中施用除磷剂、微生物菌剂及采用生...  相似文献   
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Environmental Science and Pollution Research - This paper conducts a convergence analysis on the energy-environmental efficiency to explore the differences between regions that reflect the...  相似文献   
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Environment, Development and Sustainability - Peoples’ livelihood and environmental governance are interrelated and interact with each other, which is a new starting point for the study of...  相似文献   
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杨春  刘本洪  刘蕾  张怡 《环境工程学报》2022,16(9):2838-2849
水体氟污染问题受到了广泛关注,现行的除氟技术对自然水体中氟化物的去除效果不明显,无法大范围推广应用。选择碳酸钙(CaCO3)、氯化钙(CaCl2)2种钙盐和普通硅酸盐水泥(简称水泥)对山东省胶州市南胶莱河水样进行了处理,考察了3种材料及其相应的组合对氟离子的去除效果,并筛选出适用于地表水体除氟的材料;通过改变搅拌时间和搅拌速度研究了不同扰动程度对除氟效果的影响;通过扫描电镜、能谱仪、X射线衍射分析和傅里叶红外光谱分析讨论除氟机理。结果表明,当这3种材料单独使用时,CaCO3和水泥表现出除氟效果,水泥除氟效果优于CaCO3,在添加0.5 g·L−1水泥的处理中,水样中的氟离子质量浓度由1.46 mg·L−1降至1.23 mg·L−1;CaCO3和水泥组合的除氟率高于单独CaCO3或水泥,可将水样的氟离子质量浓度由1.39 mg·L−1降至1.09 mg·L−1。改变搅拌时间和速度的实验结果表明,扰动程度增加,除氟率随之下降。表征分析结果表明,水样中氟离子主要依靠化学反应形成沉淀去除。使用水泥用于地表水除氟的步骤简单、效果明显,考虑到水泥与CaCO3组合使用表现出的协同效果以及扰动程度对除氟效果的影响,未来采用水泥处理氟污染地表水时,建议与CaCO3组合使用并采取撒施等对水体扰动较小的施工方式。  相似文献   
8.

The empirical research on the relationship between corporate environmental responsibility and environmental performance remains in the one-way positive impact and lacks the research on nonlinear relationship between them. Based on the stakeholder theory, this paper selects A-share chemical–listed companies in China from 2006 to 2017 as the research samples and uses generalized method of moments (GMM) model to investigate the impact mechanism between corporate environmental responsibility and environmental performance. The results showed that corporate environmental responsibility positively impacted on environmental performance; however, the impact was not significant. The corporate environmental performance positively and significantly impacted on environmental responsibility. Moreover, results reported that industry competition played a positive regulatory role in corporate environmental responsibility affecting environmental performance and has played a positive role in corporate environmental impact on environmental responsibility. A nonlinear relationship (inverted “U” shape) between environmental responsibility and environmental performance was found. The study results stress to establish a fair and perfect market competition mechanism to improve the environmental performance of chemical industries in China.

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9.
待测样经蒸馏、乙醚萃取、氢氧化钠反萃取后,常见干扰物质均可以除去,PCP-Na溶液在波长320nm处有最大的吸收峰,其它酚类物质在该波长处不干扰测定。本法操作简便、快速、准确、经济,稳定性好。本法测定PCP-Na的回收率,在水中为100.74%,在土壤中为91.45%。  相似文献   
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