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Science China Chemistry 2024年第9期67卷 2989-2997页

作者： Pengxin wang Xiaoyong Zhang lingqing wang Rui wang Dongxu Yang Key Laboratory of Preclinical Study for New Drugs of Gansu Province School of Basic Medical Sciences & Research Unit of Peptide ScienceChinese Academy of Medical Sciences Lanzhou University State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College School of Sciences Great Bay University Institute of Systems and Physical Biology Shenzhen Bay Laboratory

Chirality transformation is a basic, attractive, and important strategy for obtaining enantioenriched products with desired chiral elements. The reported chirality conversion reaction often involves the process from one type of chirality to another one. To better utilize the chirality transformation strategy for obtaining two or more products with different chiral elements in a single reaction, a new method of kinetic resolution accompanied by a chirality transformation protocol is proposed and successfully realized in this study. This process is used for the asymmetric oxidation of phenol compounds along with the kinetic resolution of oxaziridines. A wide scope of products, including axially chiral phenols, oxaziridines, and α-hydroxyl cyclic ketones were smoothly obtained in high levels of yields and enantioselectivities in the developed method. These products can be readily used for the synthesis of various types of chiral ligands, which are potential choices for other catalytic asymmetric reactions.

关键词： chirality transformation kinetic resolution accompanied axially chiral phenols chiral oxaziridines

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Contamination and health risk assessment of heavy metals in road dust in Bayan Obo Mining Region in Inner Mongolia, North China

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Journal of Geographical Sciences 2015年第12期25卷 1439-1451页

作者： LI Kexin LIANG Tao wang lingqing YANG Zhiping Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China

The objective of this study was to investigate the concentration and spatial distribu- tion patterns of 9 potentially toxic heavy metal elements （As, Cd, Co, Cr, Pb, Cu, Z.n, Mn, and Ni） in road dust in the Bayan Obo Mining Region in Inner Mongolia, China. Contamination levels were evaluated using the geoaccumulation index and the enrichment factor. Human health risks for each heavy metal element were assessed using a human exposure model. Results showed that the dust contained significantly elevated heavy metal elements concen- trations compared with the background soil. The spatial distribution pattern of all tested met- als except for As coincided with the locations of industrial areas while the spatial distribution of As was associated with domestic sources. The contamination evaluation indicated that Cd, Pb, and Mn in road dust mainly originated from anthropogenic sources with a rating of ＂heav- ily polluted＂ to ＂extremely polluted,＂ whereas the remaining metals originated from both natural and anthropogenic sources with a level of ＂moderately polluted＂. The non-cancer health risk assessment showed that ingestion was the primary exposure route for all metals in the road dust and that Mn, Cr, Pb, and As were the main contributors to non-cancer risks in both children and adults. Higher HI values were calculated for children （H1=1.89）, indicating that children will likely experience higher health risks compared with adults （H1=0.23）. The cancer risk assessment showed that Cr was the main contributor, with cancer risks which were 2-3 orders of magnitude higher than those for other metals. Taken in concert, the non-cancer risks posed by all studied heavy metal elements and the cancer risks posed by As Co, Cr, Cd, and Ni to both children and adults in Bayan Obo Mining Region fell within the acceptable range.

关键词： road dust heavy metal elements contamination assessment health risk assessment Bayan Obo Mining Region

Simulation on phosphorus release characteristics of Poyang Lake sediments under variable water levels and velocities

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Journal of Geographical Sciences 2017年第6期27卷 697-710页

作者： TONG Yali LIANG Tao wang lingqing LI Kexin Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China

Since the construction of the Three Gorges Dam, the Poyang Lake hydrological characteristics obviously changed. During the impoundment period of the Three Gorges Reservoir, the hydrodynamic factors of Poyang Lake varied. Water level dropped, the velocity decreased and water exchange time lengthened, which changed the release of phosphorous from sediments. In order to investigate how the hydrodynamic factors influence the release of phosphorous from sediments, we used a two-way annular flume device to simulate the release characteristics of phosphorous from sediments under variable water levels and velocities. We found that both water level rising and velocity increasing could enhance the distur- bance intensity to sediments, which caused the increase of suspended solids （SS） concentration, total phosphorus （TP） concentration in the overlying water, and the ability that phosphorus released to overlying water from sediments enhanced as well： when overlying water velocity maintained 0.3 m/s, SS concentration increased to 4035.85 mg/L at the water level 25 cm which was about 25 times compared to the minimum value and TP concentration in the overlying water also reached the maximum value at the water level 25 cm which was 1.2 times that of the value at 10 cm; when water level maintained 15 cm, SS concentration increased to 4363.35 mg/L at the velocity of 0.5 m/s which was about 28 times compared to the value of 0 m/s, and TP concentration in the overlying water increased from 0.11 mg/L to 0.44 mg/L. When the water level maintained 15 cm, the phosphorous release rate reached the maximum value of 4,86 mg/（md） at 0.4 m/s. The concentration of total dissolved phosphorous （TDP） and soluble reactive phosphate （SRP） both in overlying water and sediment-water interface were negatively correlated with pH. Using the parabolic equation, the optimum water level at a velocity of 0.3 m/s was calculated to be 0.57 cm, and the optimum velocity at water level of 15 cm was found to be 0.2

关键词： hydrodynamic factors sediment-water interface total phosphorous total dissolved phosphorous soluble reactive phosphate Poyang Lake

中国沿海乡村多功能演变及其自然和社会经济影响因素

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地理学报:英文版 2023年第9期33卷 1791-1814页

作者：王雅竹段学军王磊王凌青 Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and LimnologyCASNanjing 210008China Institute of Geographic Sciences and Natural Resources Research CASBeijing 100101China

Rural decline has become a global *** address this issue,the division of rural functions and identification of driving factors are important means of rural *** the town area as a unit,this study conducts a division and evolution analysis of rural regional functions in Jiangsu province in coastal China by constructing an evaluation system using the spatial econometric model to diagnose endogenous and exogenous driving factors of rural multifunction *** results show that the functions of agricultural supply and ecological conservation have decreased,while the functions of economic development and social security have *** production functions are concentrated in northern and central *** economic development function is mainly based on industrial development,and is the strongest in southern *** security functions are concentrated in suburban area,county centers,and key ***-value areas of ecological conservation are concentrated along lakes,the coast,and hilly areas of southern *** multifunctional development of villages and towns is affected by endogenous and exogenous factors,including economic geographic location,natural resources,economic foundation,human capital,traffic conditions,market demand,infrastructure,and environmental *** factors have a significant impact on the supply of agricultural products and the formation of ecological conservation *** effects of socioeconomic factors on these four functions differ *** study expands the theory of rural development functions,the classification and zoning paradigm,and the quantitative study of driving *** results provide a reference for practical value and policy significance for the reconstruction of rural functions and rural revitalization.

关键词： rural multifunction influencing factors spatial econometric analysis coastal China

贵屿电子垃圾拆解管控前后河流及沉积物中重金属时空分布及潜在生态风险评价

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环境科学学报 2023年第5期43卷 58-68页

作者：熊竹楠王思雨王凌青梁涛中国科学院地理科学与资源研究所陆地表层格局与模拟重点实验室北京100101 中国科学院大学中丹学院北京100190 中国科学院大学北京100049

电子垃圾的非正规拆解和回收已造成严重的水土环境污染,作为全球电子垃圾回收中心之一的广东汕头贵屿镇,在2012年集中管控前污染尤为严重.为评判近10年管控后的治污成效,本研究于2021年实测了贵屿镇河流及表层沉积物中的重金属含量,并... 详细信息

电子垃圾的非正规拆解和回收已造成严重的水土环境污染,作为全球电子垃圾回收中心之一的广东汕头贵屿镇,在2012年集中管控前污染尤为严重.为评判近10年管控后的治污成效,本研究于2021年实测了贵屿镇河流及表层沉积物中的重金属含量,并与管控前文献数据进行了对比,探讨了重金属在水和沉积物中的时空变化及潜在生态风险.结果表明,贵屿镇电子垃圾拆解导致河流与沉积物中重金属存在不同程度的输入,广泛存在于电子产品中的Cu、Zn、Ni、Pb、Cd在很大程度上超出我国其他主要流域.与管控前相比,练江贵屿段上覆水和沉积物中重金属含量总体下降,溶解态Cu含量有所上升;北港河上覆水中重金属含量降幅均在70%以上,但沉积物中Cr、Cu、Pb含量升高;练江支流沉积物中Cd、Cr、Cu、Pb含量在管控后呈降低趋势,但Zn、Ni含量受其他人为活动的影响大幅上升.贵屿镇沉积物目前仍处于极高生态风险水平,其中,Cd和Cu的潜在生态风险最高,对电子垃圾拆解的污染管控仍需持续加力.

关键词：电子拆解垃圾政策管控重金属时空分布生态风险评价贵屿

Theoretical and experimental investigations on single-atom catalysis:Pt1/FeOx for water-gas shift reaction Shan-Fei wang1,§,Yangyang Li2,3,§,Haiyan wang1,Jin-Xia Liang1(✉),Chun Zhu1

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Nano Research 2024年第9期17卷 8627-8637页

作者： Shan-Fei wang Yangyang Li Haiyan wang Jin-Xia Liang Chun Zhu Botao Qiao School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang 550025China CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

Oxide-supported metal single-atom catalysts(SACs)have exhibited excellent catalytic performance for water-gas shift(WGS)***,we report the single-atom catalyst Pt1/FeOx exhibits excellent medium temperature catalytic performance for WGS reactions by the density functional theory(DFT)calculations and experimental *** calculations indicate that H_(2)O molecules are easily dissociated at oxygen vacancies,and the formed*OH and*O are adsorbed on Pt1 single atoms and the adjacent O atoms,*** studying four possible reaction mechanisms,it is found that the optimal WGS reaction pathway is proceeded along the carboxyl mechanism(pathway III),in which the formation of*COOH intermediates can promote the stability of Pt1/FeOx SAC and the easier occurrence of WGS *** energy barrier of the rate-determining step during the entire reaction cycle is only 1.16 eV,showing the high activity for the medium temperature WGS reaction on Pt1/FeOx SAC,which was verified by experimental ***,the calculated turnover frequencies(TOFs)of CO_(2)and H_(2)formation on Pt1/FeOx at 610 K(337℃)can reach up to 1.14×10^(-3)s^(-1)·site^(-1)through carboxyl *** this work,we further expand the application potential of Pt1/FeOx SAC in WGS reaction.

关键词： water-gas shift(WGS)reaction single-atom catalyst(SAC) density functional theory(DFT) thermocatalysis

电感耦合等离子体质谱联用技术在稀土元素物源指示研究中的应用进展

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岩矿测试 2023年第1期42卷 1-15页

作者：韩萧萧梁涛王思雨熊竹楠王凌青中国科学院地理科学与资源研究所陆地表层格局与模拟重点实验室北京100101 中国科学院大学北京100049 中国科学院大学中丹学院北京101408

稀土元素(REEs)不仅是重要的战略资源,而且因其特有的地球化学属性,在追踪岩石、矿物、沉积物等物质的来源方面具有重要研究意义。近年来,随着REEs在现代社会的广泛应用,人为源REEs作为潜在新兴污染物,在自然环境中的出现频率及浓度水... 详细信息

稀土元素(REEs)不仅是重要的战略资源,而且因其特有的地球化学属性,在追踪岩石、矿物、沉积物等物质的来源方面具有重要研究意义。近年来,随着REEs在现代社会的广泛应用,人为源REEs作为潜在新兴污染物,在自然环境中的出现频率及浓度水平明显提高。然而,相比于地质源REEs,目前关于人为源REEs研究相对较少,且受检测技术的制约直接测定人为源REEs较为困难。随着仪器分析技术的发展,高选择性的离子色谱(IC)分离技术与高灵敏的电感耦合等离子体质谱(ICP-MS)技术的联用在人为源REEs分析中发挥了重要作用,该技术的元素形态分析能力使其成为人为源REEs分析的重要研究工具之一。ICP-MS及其联用技术等高精度分析技术发展,使REEs物源指示方面的研究取得革命性突破。本文系统阐述了REEs分异特征、同位素分馏、赋存形态等地球化学特征在识别物质来源、解析关键过程、示踪环境行为等方面的研究进展,主要包括:(1)REEs配分模式、同位素分异特征在传统物源指示方面有着广泛应用,研究主要基于REEs丰度或同位素分馏信息,结合相关数理统计模型,完成岩石、矿物等物质的溯源研究;(2)REEs形态特征能够为指示人类活动提供重要依据,譬如,由于使用的核磁共振钆对比剂(GBCAs)种类存在地域差异,人为源REEs赋存形态在不同地区也存在明显的不同,德国等地区自然水体中大环型GBCAs检出率较高,线型检出率较低。在此基础上,系统回顾了ICP-MS及其联用技术在REEs物源示踪研究中的相关应用进程,归纳总结了REEs在追踪物质来源、指示人类活动方面的主要研究情况,对REEs物源示踪研究发展前景作了展望。在这些分析技术中,激光剥蚀多接收等离子体质谱技术(LA-MC-ICP-MS)可以原位获得样品内部REEs同位素组成的空间分布信息;基于亲水离子色谱-电感耦合等离子体质谱联用技术(HILIC-ICP-MS)的形态分析方法可为人为源REEs研究提供“多维”数据。针对目前技术方法体系存在的不足,本文提出了开发快速便携分析技术、整合多维信息进行示踪研究、综合考虑人类活动影响的研究展望。

关键词：稀土元素赋存形态电感耦合等离子质谱法同位素分析技术形态分析技术物源指示

青海省土地利用变化及其社会经济驱动因素分析

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草业科学 2022年第12期39卷 2604-2616页

作者：李广英李红颖王凌青江峰冯朝晖青海省生态环境规划和环保技术中心青海西宁810007 生态环境部对外合作与交流中心北京100035 中国科学院地理科学与资源研究所北京100101 中国科学院西北高原生物研究所青海西宁810001

青海省是我国重要的生态安全屏障和水源涵养区,也是生态系统脆弱区和敏感区,极易受到人为活动的干扰,探究其土地利用变化特征及驱动力对于青海省土地资源的合理规划管理和生态环境保护至关重要。本研究基于1980-2018年8个时期的土地利... 详细信息

青海省是我国重要的生态安全屏障和水源涵养区,也是生态系统脆弱区和敏感区,极易受到人为活动的干扰,探究其土地利用变化特征及驱动力对于青海省土地资源的合理规划管理和生态环境保护至关重要。本研究基于1980-2018年8个时期的土地利用遥感影像解译数据,采用土地利用动态度指数、转移矩阵和土地利用程度综合指数分析方法,揭示青海各土地利用类型变化程度及空间迁移,并进一步分析土地利用/覆盖类型与23种主要社会经济指标之间的关系。结果表明:城乡建设用地是青海省年变化率最大的土地利用类型,且整体上呈现出变化程度愈加剧烈的趋势,在1990-1995年和2015-2018年面积下降,而在1995-2015年5个时段面积不断增加。青海省6种土地利用类型在2015-2018年和2000-2005年时期变化较为剧烈,其中草地和未利用土地是土地利用变化最明显的类型,两者之间互相转换也较为活跃。整体上,综合土地利用动态度呈现递增的趋势,表明研究时期内青海省土地利用朝着愈加活跃的方向发展。土地利用程度综合指数分析指出,青海省在研究时期内朝向城镇聚落发展的方向发展。人口、GDP、建筑业、工业等社会经济发展以及土地管理政策是影响该区域土地利用类型不断变化的主要驱动因素,其中城镇化率和社会经济的快速发展是导致青海省草地和林地面积下降的主要因素,也是城乡建设用地扩张的主要驱动力因子。研究结果为青海省土地利用可持续利用及发展提供科学依据。

关键词：土地利用动态变化土地利用程度人类活动城镇化社会经济发展土地管理青藏高原东部

The reformation of catalyst:From a trial-and-error synthesis to rational design

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Nano Research 2024年第4期17卷 3261-3301页

作者： Ligang wang Jiabin Wu Shunwu wang Huan Liu Yao wang Dingsheng wang Department of Chemistry Tsinghua UniversityBeijing 100084China

The appropriate catalysts can accelerate the reaction rate and effectively boost the efficient conversion of various molecules,which is of great importance in the study of chemistry,chemical industry,energy,materials and environmental ***,efficient,environmentally friendly,and easy to operate synthesis methods have been used to prepare various types of *** previous studies have reported the synthesis and characterization of the aforementioned catalysts,more still remain in trial and error methods,without in-depth consideration and improvement of traditional synthesis ***,we comprehensively summarize and compare the preparation methods of the trial-and-error synthesis strategy,structure–activity relationships and density functional theory(DFT)guided catalysts rational design for nanomaterials and atomically dispersed *** also discuss in detail the utilization of the nanomaterials and single atom catalysts for converting small molecules(H_(2)O,O_(2),CO_(2),N_(2),etc.)into value-added products driven by electrocatalysis,photocatalysis,and ***,the challenges and outlooks of mass preparation and production of efficient and green catalysts through conventional trial and error synthesis and DFT theory are featured in accordance with its current development.

关键词： trial-and-error synthesis structure–activity relationships density functional theory(DFT)guidance nanomaterials atomically dispersed catalysts

Numerical Analysis of PRISM-PY Calculations for Hard-and Soft-Core Generic Polymer Models

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Chinese Journal of Polymer Science 2024年第4期42卷 532-543页

作者： Qiang wang Department of Chemical and Biological Engineering Colorado State University1370 Campus DeliveryFort CollinsCO80523-1370USA

Generic polymer models capturing the chain connectivity and excluded-volume interactions between polymer segments can be classified, according to whether or not the 3D integral of the latter diverges, into hard- and soft-core models. Taking homogeneous systems of compressible homopolymer melts (or equivalently homopolymer solutions in an implicit, good solvent) in the continuum as an example, we recently compared the correlation effects on the structural and thermodynamic properties of the hard- and soft-core models given by the polymer reference interaction site model (PRISM) theory with the Percus-Yevick (PY) closure (Polymers 2023, 15, 1180). Here we analyzed in detail the numerical errors and behavior of the interchain pair correlation functions (PCFs) given by the PRISM-PY calculations of these models using an efficient numerical approach that we proposed. Our numerical approach has the least number of independent variables to be iteratively solved, analytically treats the discontinuities caused by the non-bonded pair potential (such as that of the hard spheres) and takes only the inverse Fourier transform of the interchain indirect PCF between polymer segments (which is continuous and decays towards 0 with increasing wavenumber much faster than both the interchain direct and total PCFs), and is essential for us to accurately solve the PRISM-PY theory for chain length N as large as 106. To capture the correlation-hole effect, the real-space cut-off in the PRISM calculations should be proportional to the square root of N.

关键词： Generic polymer models Soft potentials Polymer reference interaction site model theory