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GAC负载钴氧化物活化过一硫酸盐高效降解甲基橙

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中国给水排水 2022年第8期38卷 73-81页

作者：宋双闫博引王松雪李金成崔福义青岛理工大学环境与市政工程学院山东青岛266520 重庆大学环境与生态学院重庆400045

针对废水处理中金属氧化物粉末催化剂难以有效分离回收及稳定性较差的问题,采用颗粒活性炭(GAC)为载体,通过浸渍-煅烧的方法将钴氧化物负载到颗粒活性炭(Co@GAC),实现过一硫酸盐(PMS)的高效活化。通过扫描电镜(SEM)等手段表征了不同煅... 详细信息

针对废水处理中金属氧化物粉末催化剂难以有效分离回收及稳定性较差的问题,采用颗粒活性炭(GAC)为载体,通过浸渍-煅烧的方法将钴氧化物负载到颗粒活性炭(Co@GAC),实现过一硫酸盐(PMS)的高效活化。通过扫描电镜(SEM)等手段表征了不同煅烧温度下制备的Co@GAC的形貌和结构,并以甲基橙为目标污染物,考察了不同煅烧温度对Co@GAC催化性能的影响。还考察了初始pH、甲基橙浓度、PMS含量、Co@GAC投加量等因素对甲基橙降解效果的影响。结果表明,在煅烧温度为500℃条件下得到的Co@GAC,在初始pH为7.0、甲基橙浓度为20 mg/L、PMS浓度为0.1 mmol/L、Co@GAC投加量为1 g/L时,反应25 min后对甲基橙的降解率达到97.1%。自由基淬灭实验结果表明,Co@GAC/PMS体系中产生的硫酸根自由基(SO;)在降解甲基橙的过程中起主要作用,而羟基自由基(·OH)的贡献相对较小。另外,重复实验结果表明,Co@GAC的催化性能稳定性较好,能够实现多次重复使用,在水处理领域具有较大的应用潜力。

关键词：颗粒活性炭钴氧化物过一硫酸盐甲基橙

基于决策树的河南省主要水库水质影响因素分析

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武汉大学学报（工学版） 2019年第9期52卷 774-781页

作者：王国重李中原张继宇左其亭程焕玲黄河水文水资源科学研究院河南郑州450004 河南省水文水资源局河南郑州450003 黄河养护集团有限公司河南郑州450003 郑州大学水利与环境学院河南郑州450008 河南省水土保持监督监测总站河南郑州450008

为了探寻影响水库水环境的主要因素,以河南省3.座水库作为典型,根据其2012年的水质监测数据,采用CART决策树方法,以其中的28座为训练集,通过Modeler特征选择选出7个主要影响因素作为变量,水库水质为目标变量,建立模型,并用全部3.座水库... 详细信息

为了探寻影响水库水环境的主要因素,以河南省3.座水库作为典型,根据其2012年的水质监测数据,采用CART决策树方法,以其中的28座为训练集,通过Modeler特征选择选出7个主要影响因素作为变量,水库水质为目标变量,建立模型,并用全部3.座水库对模型进行了验证,结果表明:模型训练的准确率为100.0%,验证的准确率为94.74%;破碎度对模型的影响程度为0.43.单位面积农药施用量、单位面积施肥量、单位面积工业产值、人口密度、单位面积工业废水排放量等5个因素对模型的影响程度均为0.11,单位面积GDP对模型的影响最小,仅有0.02.决策树方法可以应用于水库的水质影响因素研究.

关键词：决策树 CART 水库水质影响因素

Impacts of rainfall and catchment characteristics on bioretention cell performance

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water Science and engineering 2019年第2期12卷 98-107页

作者： Yan-wei Sun Christine Pomeroy Qing-yun li Cun-dong Xu School of water Conservancy North China University of Water Resources and Electric PowerZhengzhou 450011China department of Civil and environmental engineering University of UtahSalt Lake CityUT 84112USA

Although many studies have evaluated the impacts of bioretention cell (BRC) design elements on hydrologic performance,few have investigated the roles played by site characteristics and rainfall *** objectives of this study were to assess the impacts of rainfall and catchments with different characteristics on the hydrologic performance of BRCs and identify important factors in sizing bioretention when hydrologic performance was oriented for the design using a modeling approach.A 10-year record of rainfall data was used to identify the frequency and magnitude of rainfall *** results showed that although the small and medium rainfall events were dominant they contributed less to the total rainfall depth than the large rainfall *** ratio of runoff coefficient to imperviousness can be used as an indicator to explain why BRCs perform differently with the same design strategy under the same rainfall *** patterns had significant impacts on the hydrologic performance of BRCs by influencing the overflow and underdrain *** performed better for rainfall events with a longer duration and lower rainfall intensity because they generated smoother runoff processes into the *** the basis of these results,the runoff coefficient is suggested for BRC surface design.

关键词： Bioretention cell Rainfall Runoff Hydrologic model Stormwater management model (SWMM)

A novel, simple and sensitive resonance scattering spectral method for the determination of chlorite in water by means of rhodamine B

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Journal of environmental Sciences 2006年第5期18卷 1000-1003页

作者： KANG Cai-yan JIANG Zhi-liang XI Dan-li HE Xing-cun college of environmental Science and engineering Donghua University Shanghai 200051 China department of Material and Chemical engineering Guilin University of Technology Guilin 541004 China School of environmental Science and Resource Guangxi Normal University Guilin 541004 China

A new resonance scattering method was proposed for the determination of chlorite, basing on the resonance scattering effect of rhodamine dye. In HCl-sodium acetate buffer solution, chlorite oxidizes 1- into 12 and the reaction of 12 and excess 1- results in If. It is respectively combined with rhodaminc dyes, including rhodamine B （RhB）, butyl rhodamine B （b-RhB）, rhodamine G （RhG） and rhodamine S （RhS）, to form association complex particles, which exhibit stronger resonance scattering （RS） effect at 400 nm. The chlorite concentration of ClO2 in the range of 0.00726-0.218 μg/ml, 0.0102-0.292 μg/ml, 0.00726-0.145 μg/ml and 0.0290- 0.174 μg/ml is respectively linear to the RS intensity of association complex particle systems at 400 nm for the RhB, b-RhB, RhG and RhS. The detection limits of the four systems were respectively 0.0043., 0.00652, 0.00580 and 0.01450μg/ml ClO2^-. In the four systems, the RhB system possesses good stability and high sensitivity. It has been applied to the analysis of chlorite in wastewater with satisfactory results.

关键词： chlorite rhodamine dye association complex particles resonance scattering effect

Influences of perfluorooctanoic acid on the aggregation of multi-walled carbon nanotubes

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Journal of environmental Sciences 2013年第3期25卷 466-472页

作者： chengliang li Andreas Schffer Harry Vereecken Marc Heggen Rong Ji Erwin Klumpp college of resources and Environment Shandong Agricultural University National engineering Laboratory for Efficient Utilization of Soil and Fertilizer {3. Biology 5-environmental Biology and Chemodynamics RWTH Aachen University Agrosphere Institute (IBG-3. Forschungszentrum Jlich GmbH Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons Forschungszentrum Jlich State Key Laboratory of Pollution Control and Resource Reuse School of the EnvironmentNanjing University Institute for Climate and Global Change Research Nanjing University

The aggregation of multi-walled carbon nanotubes （MWCNTs） in the aqueous phase not only inhibits their extensive utilization in various aspects but also dominates their environmental fate and *** role of surfactants at low concentration in the aggregation of MWCNTs has been studied,however the effect of perfluorinated surfactants at low concentration is *** understand this interfacial phenomenon,the influences of perfluorooctanoic acid （PFOA）,and sodium dodecyl sulfate （SDS） as a control,on MWCNT aggregation in the aqueous phase were examined by the UV absorbency *** of pH and cationic species on the critical coagulation concentration （CCC） value were *** CCC values were dependent on the concentration of PFOA,however a pronounced effect of SDS concentration on the CCC values was not *** CCC values of the MWCNTs were 51.6 mmol/L in NaCl and 0.28 mmol/L in CaCl 2 solutions,which suggested pronounced differences in the effects of Na＋ and Ca2＋ ions on the aggregation of the *** presence of both PFOA and SDS significantly decreased the CCC values of the MWCNTs in NaCl *** aggregation of the MWCNTs took place under acidic conditions and was not notably altered under neutral and alkaline conditions due to the electrostatic repulsion of deprotonated functional groups on the surface of the MWCNTs.

关键词： perfluorooctanoic acid aggregation multi-walled carbon nanotubes

The effect of PET calculations in DRAINMOD on drainage and crop yields predictions in a subhumid vertisol soil district

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Science china(Technological Sciences) 2009年第11期52卷 3315-3319页

作者： LUO Wan JING WeiHua JIA ZhongHua li Jin PAN YanXin water resources and Agricultural engineering {3.partment Xi’an University of TechnologyXi’an 710048China Municipal and environmental engineering department Xi’an University of TechnologyXi’an 710048China

The field hydrology model-DRAINMOD has several options for evapotranspiration (ET) calculation. The choice of each calculation method may affect modeling results because ET is one of the most important hydrologic components in field hydrology. ET calculation method may also have significant impact on crop yield predictions. As variable ET estimation methods are available nowadays, this paper presents a study of different ET inputs on simulated crop yields and drainage volume based on weather and soil data from a subhumid climate zone in china. The study results show that the effect of ET estimate on drainage and crop yield prediction is affected by crop species and growing period; more accurate ET estimate is also critical in simulating the effect of controlled drainage on field hydrology and crop production. The results of this study indicate that the effort contributed to better ET estimate is very important in model applications.

关键词： DRAINMOD PET drainage relative crop yield

红壤丘陵区不同植被覆盖阈值小流域时空分布规律

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水土保持研究 2023年第2期30卷 186-192页

作者：陈佳李忠武方怒放刘成宁珂王凌霞贵州大学农学院贵阳550025 湖南师范大学资源与环境科学学院长沙410081 湖南大学环境科学与工程学院长沙410082 西北农林科技大学黄土高原土壤侵蚀与旱地农业国家重点实验室陕西杨凌712100 国际泥沙研究培训中心北京100048

植被覆盖度是反映土壤侵蚀状况的关键指标,实施植被恢复是防治小流域土壤侵蚀的重要措施,但小流域植被覆盖度到底恢复到多少才能有效控制土壤侵蚀尚不清楚。基于土壤侵蚀治理的小流域植被覆盖度阈值效应,对红壤丘陵区3. 157个小流域2000... 详细信息

植被覆盖度是反映土壤侵蚀状况的关键指标,实施植被恢复是防治小流域土壤侵蚀的重要措施,但小流域植被覆盖度到底恢复到多少才能有效控制土壤侵蚀尚不清楚。基于土壤侵蚀治理的小流域植被覆盖度阈值效应,对红壤丘陵区3. 157个小流域2000—2015年植被覆盖度的时空变化进行了分析,评估不同植被覆盖阈值小流域时空分布规律与格局,以期精准制定小流域土壤侵蚀治理方式与对策。结果表明:(1) 2000—2015年,84%的小流域植被覆盖呈不断增加趋势,植被覆盖下降的小流域占15%,植被覆盖度基本不变的小流域仅有1%;(2)植被覆盖小于40%(低阈值带)的小流域占比小且相对稳定(3.~7%),说明大规模人工治理小流域土壤侵蚀的局面已扭转,但耕地依然是重点关注的对象;(3.植被覆盖位于40%~80%(过渡带)的小流域占比一直最高(超过83.),应采取以“自然恢复为主,人工修复为辅”的治理方式,重点关注土地利用结构和植被结构的优化配置;(4)植被覆盖大于80%(高阈值带)的小流域占比从2010年前的1%~2%上升到2015年的14%,可见具有自我修复植被覆盖条件的小流域显著增加,实施自然恢复(如封禁)是高阈值带小流域的优先选择。

关键词：植被覆盖度阈值效应土壤侵蚀小流域红壤丘陵区

基于层次分析法的澜沧江-湄公河可消耗水量分配

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武汉大学学报（工学版） 2018年第5期51卷 389-393页

作者：李奔张坤程天矫武汉大学水资源与水电工程科学国家重点实验室湖北武汉430072 武汉大学国家领土主权与海洋权益协同创新中心湖北武汉430072 贵州省水利水电勘测设计院湖北分院湖北武汉430070 湖北水利水电职业技术学院湖北武汉430070

国际河流水量分配存在很大困难,为了公平合理地分配澜沧江-湄公河水资源,维护国家权益,应用层次分析法对其进行了计算分析.针对澜沧江-湄公河的流域现状及用水需求,建立影响国际河流水量分配的指标体系,如用水量、人口、GDP等,在注重可... 详细信息

国际河流水量分配存在很大困难,为了公平合理地分配澜沧江-湄公河水资源,维护国家权益,应用层次分析法对其进行了计算分析.针对澜沧江-湄公河的流域现状及用水需求,建立影响国际河流水量分配的指标体系,如用水量、人口、GDP等,在注重可持续性、效率性并兼顾公平性的原则下,运用层次分析法定性和定量分析水量分配的影响因素,并确定各影响因素所占的权重,最终得出76.48亿m3.消耗水量的分配方案,即泰国最多,为19.91亿m3.老挝最少,为8.26亿m3.中国所分得的水量为10.3.亿m3.也能够满足自身需要.为澜沧江-湄公河的水量分配提供了一种量化方法和技术支持.

关键词：水量分配国际河流澜沧江-湄公河层次分析法一致性检验

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隧道渗漏封堵材料性能及封堵效果分析

中国公路学报 2022年第1期35卷 38-48页

作者：李平孙新飞白银范成文闵凡路河海大学岩土力学与堤坝工程教育部重点实验室江苏南京210024 南京水利科学研究院水文水资源与水利工程科学国家重点试验室江苏南京210029

地下隧道由于埋深大、水压高,存在渗漏破坏的风险,会造成经济损失和生态环境危害。因此在高水压条件下对渗漏部位如何进行快速有效封堵越来越受关注。通过以快硬硫铝酸盐水泥、5044N可再分散乳胶粉(5044N)、丙烯酸酯共聚乳液(丙乳)作为... 详细信息

地下隧道由于埋深大、水压高,存在渗漏破坏的风险,会造成经济损失和生态环境危害。因此在高水压条件下对渗漏部位如何进行快速有效封堵越来越受关注。通过以快硬硫铝酸盐水泥、5044N可再分散乳胶粉(5044N)、丙烯酸酯共聚乳液(丙乳)作为封堵原材料,从封堵材料超早期性能角度对封堵效果进行探讨,并就聚合物种类和聚灰比对超早期性能及渗漏封堵效果的影响进行了分析。研究结果表明:5044N改性封堵材料初凝及终凝时间分别缩短14%和19%,而丙乳则延缓封堵材料的凝结时间;5044N改性封堵材料的黏度突变点提前40~120 s,可以采用封堵材料黏度突变点表征初凝时间,封堵材料黏度变化规律符合指数函数形式。将封堵材料的水化硬化过程分为平台期、突变期和稳定期,突变期的封堵材料已经形成固体骨架,根据波速突变点来表征终凝时间,5044N改性封堵材料波速突变点提前248 s,固相物质生成速率提高了55%~60%。聚灰比对封堵材料超早期性能的影响具有峰值特征,5044N在聚灰比为0.03.表现较好。使用扫描电子显微镜(SEM)对封堵材料凝块做出细观结构分析,发现5044N与水泥水化形成大量C—S—H凝胶包裹钙矾石,可有效填补孔隙,增加密实度。渗漏封堵试验中,利用出水口水流流速量化封堵效果,封堵效果随着黏度增长而提高,5044N改性封堵材料可提前2 min发挥封堵作用。

关键词：隧道工程渗漏封堵材料流变特性水化硬化特征封堵效果