The coexistence of cadmium(Cd(Ⅱ))and arsenate(As(Ⅴ))pollution has long been an environmental problem.Biochar,a porous carbonaceous material with tunable functionality,has been used for the remediation of contaminate...The coexistence of cadmium(Cd(Ⅱ))and arsenate(As(Ⅴ))pollution has long been an environmental problem.Biochar,a porous carbonaceous material with tunable functionality,has been used for the remediation of contaminated soils.However,it is still challenging for the dynamic quantification and mechanistic understanding of the simultaneous sequestration of multi-metals in biochar-engineered environment,especially in the presence of anions.In this study,ferrihydrite was coprecipitated with biochar to investigate how ferrihydritebiochar composite affects the fate of heavy metals,especially in the coexistence of Cd(Ⅱ)and As(Ⅴ).In the solution system containing both Cd(Ⅱ)and As(Ⅴ),the maximum adsorption capacities of ferrihydrite-biochar composite for Cd(Ⅱ)and As(Ⅴ)reached 82.03μmol/g and 531.53μmol/g,respectively,much higher than those of the pure biochar(26.90μmol/g for Cd(Ⅱ),and 40.24μmol/g for As(Ⅴ))and ferrihydrite(42.26μmol/g for Cd(Ⅱ),and 248.25μmol/g for As(Ⅴ)).Cd(Ⅱ)adsorption increased in the presence of As(Ⅴ),possibly due to the changes in composite surface charge in the presence of As(Ⅴ),and the increased dispersion of ferrihydrite by biochar.Further microscopic and mechanistic results showed that Cd(Ⅱ)complexed with both biochar and ferrihydrite,while As(Ⅴ)was mainly complexed by ferrihydrite in the Cd(Ⅱ)and As(Ⅴ)coexistence system.Ferrihydrite posed vital importance for the co-adsorption of Cd(Ⅱ)and As(Ⅴ).The different distribution patterns revealed by this study help to a deeper understanding of the behaviors of cations and anions in the natural environment.展开更多
国家基因库生命大数据平台(China National GeneBank DataBase,CNGBdb)是一个致力于生命科学多组学数据归档和开放共享的数据库平台,是深圳国家基因库的核心功能“三库两平台”中生物信息数据库的对外服务平台,拥有深圳国家基因库丰富...国家基因库生命大数据平台(China National GeneBank DataBase,CNGBdb)是一个致力于生命科学多组学数据归档和开放共享的数据库平台,是深圳国家基因库的核心功能“三库两平台”中生物信息数据库的对外服务平台,拥有深圳国家基因库丰富的样本资源、数据资源、合作项目资源和强大的数据计算和分析能力等优势。生命科学研究已经进入到了一个以高通量多组学数据为基础的大数据时代,迫切需要加强国际合作和信息共享。随着中国经济的发展和在生命科学研究领域的研究项目投入力度的加大,需要建立相关的生命大数据归档和共享的平台,来促进我国生命科学研究项目中生成的基因组学数据的系统管理、开放共享与合理利用。目前,CNGBdb主要提供生命科学研究相关的数据归档、知识搜索、数据管理、数据计算和数据服务等服务。其归档和共享的数据类型,主要包括项目、样本、实验、测序、组装、变异、序列等。截止2020年5月22号,CNGBdb已接受了全球生命科学科研工作者提交的研究项目达2176个,归档的基因组学数据量超过2221 TB。未来,CNGBdb将继续推动生命科学研究多组学数据的开放共享和产业应用,完善基因组学数据的归档和共享功能,提升其服务生命科学数据开放共享的能力。CNGBdb的网址是:https://db.cngb.org/。展开更多
Ireproving the quality and experience perceived by the user is fundamental when de- veloping multimedia technologies, products, and services. Quality of experience （QoE） involves subjective perception, user behavior...Ireproving the quality and experience perceived by the user is fundamental when de- veloping multimedia technologies, products, and services. Quality of experience （QoE） involves subjective perception, user behavior and needs, appropriateness, con- text, and usability of delivered content. Modeling QoE is critical for enhancing QoE in various nmhimedia applications. In this special issue,展开更多
To achieve economical compensation for the huge-capacity negative sequence currents generated by high-speed railway load, an electromagnetic hybrid compensation system(EHCS) and control strategy is proposed.The EHCS i...To achieve economical compensation for the huge-capacity negative sequence currents generated by high-speed railway load, an electromagnetic hybrid compensation system(EHCS) and control strategy is proposed.The EHCS is made up of a small-capacity railway static power conditioner(RPC) and a large-capacity magnetic static var compensator(MSVC). Compared with traditional compensation methods, the EHCS makes full use of the SVC’s advantages of economy and reliability and of RPC’s advantages of technical capability and flexibility. Based on the idea of injecting a negative sequence, the compensation principle of the EHCS is analyzed in detail. Then the minimum installation capacity of an EHCS is theoretically deduced. Furthermore, a constraint optimization compensation strategy that meets national standards, which reduces compensation capacity further, is proposed. An experimental platform based on a digital signal processor(DSP) and a programmable logic controller(PLC) is built to verify the analysis. Simulated and experimental results are given to demonstrate the effectiveness and feasibility of the proposed method.展开更多
基金supported by the National Key R&D Program of China(No.2019YFC1803900)the National Natural Science Foundation of China(No.42107264)+1 种基金Guangdong Basic and Applied Basic Research Foundation(No.2020A1515110610)Guangzhou Basic and Applied Basic Research Foundation(No.202002030364)。
文摘The coexistence of cadmium(Cd(Ⅱ))and arsenate(As(Ⅴ))pollution has long been an environmental problem.Biochar,a porous carbonaceous material with tunable functionality,has been used for the remediation of contaminated soils.However,it is still challenging for the dynamic quantification and mechanistic understanding of the simultaneous sequestration of multi-metals in biochar-engineered environment,especially in the presence of anions.In this study,ferrihydrite was coprecipitated with biochar to investigate how ferrihydritebiochar composite affects the fate of heavy metals,especially in the coexistence of Cd(Ⅱ)and As(Ⅴ).In the solution system containing both Cd(Ⅱ)and As(Ⅴ),the maximum adsorption capacities of ferrihydrite-biochar composite for Cd(Ⅱ)and As(Ⅴ)reached 82.03μmol/g and 531.53μmol/g,respectively,much higher than those of the pure biochar(26.90μmol/g for Cd(Ⅱ),and 40.24μmol/g for As(Ⅴ))and ferrihydrite(42.26μmol/g for Cd(Ⅱ),and 248.25μmol/g for As(Ⅴ)).Cd(Ⅱ)adsorption increased in the presence of As(Ⅴ),possibly due to the changes in composite surface charge in the presence of As(Ⅴ),and the increased dispersion of ferrihydrite by biochar.Further microscopic and mechanistic results showed that Cd(Ⅱ)complexed with both biochar and ferrihydrite,while As(Ⅴ)was mainly complexed by ferrihydrite in the Cd(Ⅱ)and As(Ⅴ)coexistence system.Ferrihydrite posed vital importance for the co-adsorption of Cd(Ⅱ)and As(Ⅴ).The different distribution patterns revealed by this study help to a deeper understanding of the behaviors of cations and anions in the natural environment.
文摘国家基因库生命大数据平台(China National GeneBank DataBase,CNGBdb)是一个致力于生命科学多组学数据归档和开放共享的数据库平台,是深圳国家基因库的核心功能“三库两平台”中生物信息数据库的对外服务平台,拥有深圳国家基因库丰富的样本资源、数据资源、合作项目资源和强大的数据计算和分析能力等优势。生命科学研究已经进入到了一个以高通量多组学数据为基础的大数据时代,迫切需要加强国际合作和信息共享。随着中国经济的发展和在生命科学研究领域的研究项目投入力度的加大,需要建立相关的生命大数据归档和共享的平台,来促进我国生命科学研究项目中生成的基因组学数据的系统管理、开放共享与合理利用。目前,CNGBdb主要提供生命科学研究相关的数据归档、知识搜索、数据管理、数据计算和数据服务等服务。其归档和共享的数据类型,主要包括项目、样本、实验、测序、组装、变异、序列等。截止2020年5月22号,CNGBdb已接受了全球生命科学科研工作者提交的研究项目达2176个,归档的基因组学数据量超过2221 TB。未来,CNGBdb将继续推动生命科学研究多组学数据的开放共享和产业应用,完善基因组学数据的归档和共享功能,提升其服务生命科学数据开放共享的能力。CNGBdb的网址是:https://db.cngb.org/。
文摘Ireproving the quality and experience perceived by the user is fundamental when de- veloping multimedia technologies, products, and services. Quality of experience （QoE） involves subjective perception, user behavior and needs, appropriateness, con- text, and usability of delivered content. Modeling QoE is critical for enhancing QoE in various nmhimedia applications. In this special issue,
基金supported by National Key Technology Support Program(No.2013BAA02B00)National Natural Science Foundation of China(No.50807041)+3 种基金Asia Pacific Economic Cooperation FundHubei province science and technology support program(No.2014BAA013)the Fundamental Research Funds for the Central Universities(No.2042014kf0233)the Fundamental Research Funds for the Central Universities(No.2014207020202)
文摘To achieve economical compensation for the huge-capacity negative sequence currents generated by high-speed railway load, an electromagnetic hybrid compensation system(EHCS) and control strategy is proposed.The EHCS is made up of a small-capacity railway static power conditioner(RPC) and a large-capacity magnetic static var compensator(MSVC). Compared with traditional compensation methods, the EHCS makes full use of the SVC’s advantages of economy and reliability and of RPC’s advantages of technical capability and flexibility. Based on the idea of injecting a negative sequence, the compensation principle of the EHCS is analyzed in detail. Then the minimum installation capacity of an EHCS is theoretically deduced. Furthermore, a constraint optimization compensation strategy that meets national standards, which reduces compensation capacity further, is proposed. An experimental platform based on a digital signal processor(DSP) and a programmable logic controller(PLC) is built to verify the analysis. Simulated and experimental results are given to demonstrate the effectiveness and feasibility of the proposed method.
