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Dynamic coupling of ferrihydrite transformation and associated arsenic desorption/Redistribution mediated by sulfate-reducing bacteria

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Journal of Environmental Sciences 2024年第1期135卷 39-50页

作者： Wenjing Zhou Huiyan Zhu Shiwen Hu Bowei Zhang Kun Gao Zhi Dang Chongxuan Liu State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control School of Environmental Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of EducationSouth China University of TechnologyGuangzhou 510006China

Sulfate-reducing bacteria play an important role in the geochemistry of iron(oxyhydr)oxide and arsenic(As)in natural environments;however,the associated reaction processes are yet to be fully understood.In this study,batch experiments coupled with geochemical,spectroscopic,microscopic,and thermodynamic analyses were conducted to investigate the dynamic coupling of ferrihydrite transformation and the associated As desorption/Redistribution mediated by Desulfovibrio vulgaris(D.vulgaris).The results indicated that D.vulgaris could induce ferrihydrite transformation via S^(2-)-driven and direct reduction processes.In the absence of SO_(4)^(2-),D.vulgaris directly reduced ferrihydrite,and As desorption and re-sorption occurred simultaneously during the partial transformation of ferrihydrite to magnetite.The increase in SO_(4)^(2-)loading promoted the S^(2-)-driven reduction of ferrihydrite and accelerated the subsequent mineralogical transformation.In the low and medium SO_(4)^(2-)treatments,ferrihydrite was completely transformed to a mixture of magnetite and mackinawite,which increased the fraction of As in the residual phase and stabilized As.In the high SO_(4)^(2-)treatment,although the replacement of ferrihydrite by only mackinawite also increased the fraction of As in the residual phase,22.1%of the total As was released into the solution due to the poor adsorption affinity of As to mackinawite and the conversion of As^(5+)to As^(3+).The mechanisms of ferrihydrite reduction,mineralogy transformation,and As mobilization and Redistribution mediated by sulfate-reducing bacteria are closely related to the surrounding SO_(4)^(2-)loadings.These results advance our understanding of the biogeochemical behavior of Fe,S,and As,and are helpful for the risk assessment and remediation of As contamination.

关键词： Sulfate-reducing bacteria Arsenic Ferrihydrite Transformation Redistribution

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Molecular sieve based Janus separators for Li-ions Redistribution to enable stable lithium deposition

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Nano Research 2022年第6期15卷 5143-5152页

作者： Huanyu Xie Zhimeng Hao Shuai Xie Yadong Ye Wei Zhang Zhaowei Sun Song Jin Hengxing Ji Jun Chen Hefei National Laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Materials for Energy ConversionDepartment of Applied ChemistryUniversity of Science and Technology of ChinaHefei 230026China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjin 300071China

During operation of a lithium metal battery,uneven lithium deposition often results in the growth of lithium dendrites and causes a rapid decay in battery performance and even leads to safety issues.This is still the main hurdle hindering the practical application of lithium metal anodes.We report a new type of Janus separator fabricated by introducing a molecular sieve coating on the surface of the polypropylene separator that serves as a Redistribution layer for lithium ions.Our results show that using this layer,the growth of lithium dendrites can be largely inhibited and the battery performance greatly improved.In a typical Li||Cu half-cell with the Janus separator,the Coulombic efficiency of the lithium metal anode can be maintained at>98.5%for over 500 cycles.The cycling life span is also extended by a factor of 8 in the Li||Li symmetric cell.Furthermore,the high-strength coating improves the mechanical properties of the separator,thus enhancing safety.The effectiveness of our strategy is demonstrated by both the inhibited growth of lithium dendrites and the improved battery performance.Our methodology could eventually be generalized for electrode protection in other battery systems.

关键词： Janus separator molecular sieve Redistribution lithium metal anode deposition

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Redistribution of Li-ions using covalent organic frameworks towards dendrite-free lithium anodes:a mechanism based on a Galton Board

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Science China Chemistry 2020年第9期63卷 1306-1314页

作者： Huanyu Xie Qing Hao Hongchang Jin Shuai Xie Zhaowei Sun Yadong Ye Chaohui Zhang Dong Wang Hengxing Ji Li-Jun Wan Hefei National Laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Materials for Energy ConversionDepartment of Applied ChemistryUniversity of Science and Technology of ChinaHefei 230026China CAS Key Laboratory of Molecular Nanostructure and Nanotechnology Institute of ChemistryChinese Academy of SciencesBeijing 100190China

Because of its high theoretical specific capacity and low reduction potential,Li metal is considered to be key to reaching high energy density in rechargeable batteries.In this context,most of the research has focused on suppressing dendrite formation during Li deposition to improve the cycling reversibility and safety of the batteries.Here,covalent organic framework(COF)film coating on a commercial polypropylene separator is applied as an ion redistributor to eliminate Li dendrites.The COF crystallites consist of ordered nanochannels that hinder the movement of anions while allowing Li-ions to transport across,leading to a high Li-ion transference number of 0.77±0.01.The transport of Li-ions across the COF film can be considered to be analogous to beads passing through a Galton Board,a model that demonstrates a statistical concept of a normal distribution.Thus,an even distribution of Li-ions is obtained at the COF/Li metal interface.The controlled Li-ion flux yields a smooth Li metal surface after 1,000 h(500 times)of cycling,leading to a significantly improved cycling stability and reversibility,as demonstrated by Cu||Li half cells,Li||Li symmetric cells,and Li Fe PO4||Li full cells.These results suggest that,following the principle of a Galton Board,nanopore insulators such as COF-based materials are effective ion distributors for the different energy storage or conversion systems.

关键词： Redistribution dendrite-free lithium metal anode COFs Galton Board

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Effect of moisture regime on the Redistribution of heavy metals in paddy soil

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Journal of Environmental Sciences 2011年第3期23卷 434-443页

作者： Shunan Zheng Mingkui Zhang Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition College of Environmental and Resource Sciences Zhejiang University IIangzhou 310029 China Agro-Environmental Protection Institute Ministry of Agriculture Tianjin 300191 China Key Laboratory of Production Environment and Agro-product Safer Ministry of Agriculture Tianjin 300191 China Tianjin Key Laboratory of Agro-environment and Agro-product Safety Tianjin 300191 China

Sequential extraction procedure was applied to assess the dynamics of solid-phase transformation of added Cu, Pb, Cd, and Hg in a typical Chinese paddy soil incubated under three moisture regimes （75% field capacity, wetting-drying cycle, and flooding）. The heavy metals spiked in the soil were time-dependently transferred from the easily extractable fraction （the exchangeable fraction） into less labile fractions （Fe-Mn oxide- and organic matter-bound fractions）, and thus reduced lability of the metals. No significant changes were found for the carbonate-bound and residual fractions of the heavy metals in the soil during the whole incubation. Change rate of the mobility factor （MF）, a proportion of weakly bound fractions （exchangeable and carbonate-bound） in the total metal of soil, reflected the transformation rate of metal speciation from the labile fractions toward stable fractions. It was found that soil moisture regime did not change the direction and pathways of transformation of metal speciation, but it significantly affected the transformation rate. In general, the paddy soil under flooding regime had higher metal reactivity compared with 75% field capacity and wetting-drying cycle regimes, resulting in the more complete movement of metals toward stable fractions. This might be related to the increased pH, precipitation of the metals with sulfides and higher concentration of amorphous Fe oxides under submerged condition.

关键词： heavy metal speciation moisture regime Redistribution paddy soil

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Change and Redistribution of Immature Fiber Number during Cotton Carding Based on Different Taker-in Speeds

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Journal of Donghua University(English Edition) 2016年第4期33卷 625-628页

作者：于学智郭昕曹继鹏 Liaoning Key Laborary of Functional Textile Materials Eastern Liaoning University School of Clothing & Textile Eastern Liaoning University

The change and Redistribution of immature fiber number after cotton carding were investigated under different taker-in speeds.The immature fiber contents (IFCs) of card sliver,flat strips,takerin droppings and cylinder screen droppings (including droppings under cylinder screen and cylinder-doffer triangle section) produced under different taker-in speeds were tested by using USTER advanced fiber information system (AFIS). Based on these results and relevant data,immature fiber number was calculated. Results show that the carding process makes the immature fiber number increase. After carding, immature fibers are distributed mainly in card sliver,accounting for approximately 90% in their total number. All of the cylinder screen,taker-in and flat have the functions of excluding immature fibers; furthermore,IFC in cylinder screen droppings is the highest,followed successively by those in taker-in droppings,flat strips and card sliver. The IFC of card sliver is the lowest when the taker-in speeds are 1000 and 1400 r/min.

关键词： taker-in speed immature fiber content(IFC) fineness carding Redistribution

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Solute Redistribution and micromechanical properties of rapidly solidified multicomponent Ni-based alloys

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Science China(Technological Sciences) 2019年第3期62卷 472-477页

作者： YAN Na WANG ZiHua RUAN Ying WEI BingBo MOE Key Laboratory of Materials Physics and Chemistry under Extraordinary Conditions Department of Applied PhysicsNorthwestern Polytechnical University

The solute trapping effect and microhardness enhancement of quaternary Ni-5%Cu-5%Ag-5%Sn and quinary Ni-5%Cu-5%Ag-5%Sn-5%Ge alloys during rapid dendritic solidification are investigated by glass fluxing technique. In these two alloys, the experimental maximum undercoolings of 310 K(0.18 T_L) and 220 K(0.13 T_L) have been achieved and the rapidly solidified microstructures are composed of α(Ni) and(Ag) solid solution phases. The morphological transition from coarse dendrite into equiaxed structure is observed for α(Ni) phase with the increase of undercooling. The dendritic growth velocity of α(Ni) phase in quaternary Ni-5%Cu-5%Ag-5%Sn alloy is larger than that in quinary Ni-5%Cu-5%Ag-5%Sn-5%Ge alloy, which increases firstly and then decreases with the enhancement of bulk undercooling. The Vickers hardness of α(Ni) phase in these two alloys is enhanced with the increase of undercooling, which is attributed mainly to the grain refinement effect. Meanwhile, the solute trapping effect of Cu, Sn and Ge elements in the α(Ni) phase also contributes to the microhardness enhancement under large undercoolings. The addition of Ge element effectively increases the microhardness of α(Ni) phase due to solute strengthening mechanism.

关键词： high undercooling dendritic growth solute Redistribution microhardness enhancement

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Who Are Hakka People?A Discussion of the Redistribution and Reco of the Hakka People in the Hakka Policies During Shui-Bian Chen’s Term as President

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Journal of Literature and Art Studies 2017年第2期7卷 195-200页

作者： CHANG Chia-Chia Tunghai University TaichungTaiwan R.O.C.

This study discusses the contents and methods of the implementation of Hakka policies during Shui-Bian Chen’s term as president from the viewpoint of Redistribution and recognition proposed by Nancy Fraser, and finds that the Hakka people mostly feel inferior and are not willing to identify themselves as Hakkas. The issue of “‘who’ are Hakka people” thus emerged during the implementation of the Hakka policies.

关键词： Redistribution recognition Hakka policy Hakka identification

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Effects of nitrogen fertilization strategies on nitrogen use efficiency in physiology, recovery, and agronomy and Redistribution of dry matter accumulation and nitrogen accumulation in two typical rice cultivars in Zhejiang, China

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第3期8卷 208-216页

作者： XIE Wen-xia, WANG Guang-huo, ZHANG Qi-chun, GUO Hai-chao (Institute for Soil and Water Resources and Environment, Zhejiang University, Hangzhou 310029, China) Institute for Soil and Water Resources and Environment Zhejiang University Hangzhou 310029 China.

Field experiments were conducted in farmers’ rice fields in 2001 and 2002 to study the effects of nitrogen (N) man-agement strategies on N use efficiency in recovery (RE), agronomy (AE) and physiology (PE) and Redistribution of dry matter accumulation (DMA) and nitrogen accumulation (NA) in two typical rice cultivars in Jinhua, Zhejiang Province. This study aimed mainly at identifying the possible causes of poor fertilizer N use efficiency (NUE) of rice in Zhejiang by comparing farmers’ fertilizer practice (FFP) with advanced site-specific nutrient management (SSNM) and real-time N management (RTNM). The results showed that compared to FFP, SSNM and RTNM reduced DMA and NA before panicle initiation and increased DMA and NA at post-flowering. There is no significant difference between SSNM and FFP in post-flowering dry matter Redistribution (post-DMR) and post-flowering nitrogen Redistribution (post-NR). These results suggest that high input rate of fertilizer N and improper fertilizer N timing are the main factors causing low NUE of irrigated rice in the farmer’s routine practice of Zhejiang. With SSNM, about 15% of the current total N input in direct-seeding early rice and 45% in single rice could be reduced without yield loss in Zhejiang, China.

关键词： Recovery N use efficiency (RE) Agronomic N use efficiency (AE) Physiological N use efficiency (PE) Nitrogen management Rice Accumulation and Redistribution

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Gold Redistribution in Shangmanggang red-clay gold deposit, western Yunnan Province, China

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Chinese Science Bulletin 1999年第S2期44卷 214-216页

作者： YANG Zhusen, LI Hongyang, GAO Zhenmin, LUO Taiyi, RAO Wenbo and DING Zhenju Open Laboratory of Deposit Geochemistry, Iustitute of Geoehemistry, Chinese Academy of Sciences, Guiyang 550002, China Open Laboratory of Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

AFTER the discovery of lateritic gold deposits in the world during the 1980s, many similar oxidized golddeposits have been discovered in southern China since 1989. Because the incomplete lateritization ofthe regolith compared with the laterite, these oxidized gold deposits were called the red-clay type gold deposits by Prof. Tu Guangzhi. The Shangmanggang gold deposit is a typical representative of the red-claytype gold deposit in western Yunnan Province. 1 Geology, climate, and geomorphology The Shangmanggang red-clay gold deposit is located in Luxi region, between Zhefang and LuxiCenozoic basins along the Longling-Runli Fault trending northeast. The northwestern flank of the basinsconsists of the Proterozoic Gaoligong Group composed of greenschist to amphibolitic metamorphic

关键词： gold Redistribution red-clay type of gold deposit Shangmanggang gold deposit Yunnan.

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再分配的收入差距调节效应：城乡和国际比较

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财政与税务 2019年第6期

作者：耿晋梅岳树民

本文以CHNS收入分类数据为基础，对全国城乡家庭居民收入的初次分配和再分配收入差距进行了测算和分析。结果表明，中国居民初次分配收入的基尼系数高出OECD国家平均值13.9％，与金砖国家水平相当；再分配后，发达国家的居民收入差距大... 详细信息

本文以CHNS收入分类数据为基础，对全国城乡家庭居民收入的初次分配和再分配收入差距进行了测算和分析。结果表明，中国居民初次分配收入的基尼系数高出OECD国家平均值13.9％，与金砖国家水平相当；再分配后，发达国家的居民收入差距大幅下降，再分配的收入差距调节效应为0.172，中国仅为0.085；尽管城镇地区转移支付的调节效应高于多数发达国家，但税收的调节效应和农村地区转移支付的调节效应微弱，中国居民可支配收入差距还是远高于绝大多数发达国家，高出平均值48％。

关键词：再分配初次分配调节效应 Redistribution primary distribution income Redistribution effect

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