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Assessing high resolution oxidation-reduction potential and soluble reactive phosphorus variation across vertical sediments and water layers in Xinghu Lake:A novel laboratory approach

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Journal of Environmental Sciences 2010年第7期22卷 982-990页

作者： yingzhi Li Beicheng Xia Jiaying Zhang Chuanhong Li Wenzhuan Zhu School of Environmental Sciences and Engineering Sun Yat-sen University Guangzhou 510275 China Huizhou Institution of Environmental Science Huizhou 516001 China

To understand the transfer process of soluble reactive phosphorus （SRP） on the lake sediment-water interface in a mesotrophic shallow lake in South China, the SRP concentrations and the oxidation-reduction potential （ORP） across the sediment-water interfaces were continually monitored. Sediment samples were collected from Xinghu Lake in Guangdong Province. The ORP dynamics at different layers of overlying water was similar for six experimental systems, whereas those in porewater were significantly different. The ORP in overlying water was 200-300 mV higher than those in sediments. The oxygen penetration depth ranged from 2 to 10 mm in Xiannu Lake sediments. The variation amplitudes of ORP increased with sediment depth, but the mean ORP values were all about 218 mV. The SRP concentrations in porewater maintained at a low level of about 0.049 mg/L because of high atom ratio of total iron and total manganese to total phosphorus. The SRP concentrations and variation amplitudes in porewater increased with sediment depth. The SRP in overlying water mainly originated from S RP transference of the porewater of middle and bottom sediments （3-15 cm）. The ORP variation and SRP transfer in porewater played important roles in changing SRP concentrations. A distinct SRP concentration gradient appeared in overlying water when intense exchange occurred at the sediment-water interface; therefore, it was necessary to monitor the SRP concentration profiles to accurately estimate the internal loading.

关键词： sediment-water interface soluble reactive phosphorus oxidation-reduction potential

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Continuous preparation of strong and tough PVA nanocomposite fibers by mechanical stretching-assisted salting-out treatment

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Nano Research 2024年第4期17卷 3156-3163页

作者： Hang Chen Guangze Yang yingzhi Sun Yichao Xu Mingjie Liu Key Laboratory of Bioinspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityBeijing 100191China Research Institute for Frontier Science Beihang UniversityBeijing 100191China International Research Institute for Multidisciplinary Science Beihang UniversityBeijing 100191China

Polymer composite fibers with superior properties such as excellent combined strength and toughness and biocompatibility can be used in high-tech applications of braided protective devices and smart wearable,however the research of high-performance polymer composite fiber remains in the infant *** we present a strategy to produce strong and tough anisotropic polymer nanocomposite fibers with orientedly aligned salt rods using mechanical stretching-assisted salting-out *** prepared nanocomposite fibers have a tensile strength of up to 786±2.7 MPa and an elongation at break of 81%,and the anisotropic fibers exhibit good transmission of mechanical vibration in the longitudinal direction with high *** the fabrication process,the salt builds up into oriented rods during the directional salting process,and the polymer is confined to the 150 nm domain between the rods after the solvent is completely evaporated,giving the nanocomposite fibers superior mechanical *** presented strategy can be applied to the continuous mass production of nanocomposite fibers and is also generalizable to other polymer nanocomposites,which could extend the applicability of nanocomposite fibers to conditions involving more demanding mechanical loading and mechanical vibration transmission.

关键词： poly(vinyl alcohol)(PVA)nanofibers oriented structure ultrastrong and stiff mechanical vibration transmission salting out continuous production

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Comparison of multinomial logistic regression and logistic regression： which is more efficient in allocating land use？

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Frontiers of Earth Science 2014年第4期8卷 512-523页

作者： yingzhi LIN Xiangzheng DENG Xing LI Enjun MA School of Mathematics and Physics China University of Geosciences Wuhan 430074 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Center for Chinese Agricultural Policy Chinese Academy of Sciences Beijing 100101 China

Spatially explicit simulation of land use change is the basis for estimating the effects of land use and cover change on energy fluxes, ecology and the environment. At the pixel level, logistic regression is one of the most common approaches used in spatially explicit land use allocation models to determine the relationship between land use and its causal factors in driving land use change, and thereby to evaluate land use suitability. However, these models have a drawback in that they do not determine/ allocate land use based on the direct relationship between land use change and its driving factors. Consequently, a multinomial logistic regression method was introduced to address this flaw, and thereby, judge the suitability of a type of land use in any given pixel in a case study area of the Jiangxi Province, China. A comparison of the two regression methods indicated that the proportion of correctly allocated pixels using multinomial logistic regression was 92.98%, which was 8.47% higher than that obtained using logistic regression. Paired t-test results also showed that pixels were more clearly distinguished by multinomial logistic regression than by logistic regression. In conclusion, multinomial logistic regression is a more efficient and accurate method for the spatial allocation of land use changes. The application of this method in future land use change studies may improve the accuracy of predicting the effects of land use and cover change on energy fluxes, ecology, and environment.

关键词： multinomial logistic regression land usechange logistic regression land use suitability land useallocation

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An equilibrium analysis of the land use structure in the Yunnan Province, China

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Frontiers of Earth Science 2014年第3期8卷 393-404页

作者： Jiao LUO Jinyan ZHAN yingzhi LIN Chunhong ZHAO State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100875 China School of Mathematics and Physics China University of Geosciences Wuhan 430074 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Center for Chinese Agricultural Policy Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

Global land use structure is changing rapidly due to unceasing population growth and accelerated urbanization, which leads to fierce competition between the rigid demand for built-up area and the protection of cultivated land, forest, and grassland. It has been a great challenge to realize the sustainable development of land resources. Based on a computable general equilibrium model of land use change with a social accounting matrix dataset, this study implemented an equilibrium analysis of the land use structure in the Yunnan Province during the period of 2008-2020 under three scenarios, the baseline scenario, low TFP （total factor productivity） scenario, and high TFP scenario. The results indicated that under all three scenarios, area of cultivated land declined signifi- cantly along with a remarkable expansion of built-up area, while areas of forest, grassland, and unused land increased slightly. The growth rate of TFP had first negative and then positive effects on the expansion of built-up area and decline of cultivated land as it increased. Moreover, the simulated changes of both cultivated land and built-up area were the biggest under the low TFP scenario, and far exceeded the limit in the Overall Plan for Land Utilization in the Yunnan Province in 2020. The scenario-based simulation results are of important reference value for policy-makers in making land use decisions, balancing the fierce competition between the protection of cultivated land and the increasing demand for built-up area, and guaranteeing food security, ecological security, and the sustainable development of land resources.

关键词： land use land use structure computable general equilibrium model of land use change socialaccounting matrix scenarios Yunnan Province

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Identifying Key Environmental Factors Influencing Spatial Variation of Water Quality in Upper Shitoukoumen Reservoir Basin in Jilin Province,China

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Chinese Geographical Science 2009年第4期19卷 365-374页

作者： TANG Yanling ZHANG Guangxin YANG Yuesuo GAO yingzhi Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China College of Environment ＆ Resources Jilin University Changchun 130026 China School of Earth Sciences Cardiff University Park Place Cardiff CF103 YE UK Key Laboratory for Vegetation Ecology of Ministry of Education Northeast Normal University Changchun 130024 China

Based on the observed data in monitored drainage areas and GIS spatial analysis tools,watershed basic database of Shitoukoumen Reservoir Basin was *** multivariate analysis and redundancy analysis(RDA) were used to analyze the spatial and temporal variations of water quality,identify the key environmental factors and their patterns influencing the spatial variation of water quality,and determine the main types and forms of the non-point source(NPS) pollutant export controlled by the key environmental *** results show that different patterns of environmental factors lead to great changes in water quality at spatial and seasonal *** selected environmental factors explain 64.5% and 68.2% of the spatial variation of water quality over dry season and rainy season,respectively,which shows clear seasonal *** dry season,residential land is the most important environmental factor,which possesses 35.4% of the spatial variation,and drainage area is the second key environmental factor,which possesses 17.0% of spatial variation in the total *** rainy season,slope length and drainage area are the key environmental factors,which possess 29.3% of the spatial variation *** land influences nitrogen export by changing NH4+-N and particulate organic nitrogen(PON) discharge over dry season,and drainage area controls phosphorus export by regulating dissolved phosphorus(DP) drainage over dry season and phosphorus associated particulate(PAP) loss over rainy season,*** slope length is an important environmental factor,it does not influence NPS pollutant *** is interesting that soil organic matter,as a minor environmental factor,highly determines phosphorus and nitrogen export by enhancing the DP,PAP and PON loss.

关键词： non-point source pollution key environmental factor redundancy analysis Shitoukoumen Reservoir

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Guidance Value of Marine Functional Zoning System to Allocation of China's Marine Resources

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Asian Agricultural Research 2015年第9期7卷 70-72页

作者： yingzhi CAO Guanshun he National Marine Data and Information Service

The issue of marine resources is receiving closer and closer attention of national marine management authorities. For this issue,it is necessary to seek basis from legal institutions of marine functional zoning system. This paper analyzed basic connotation,development process and basic characteristics of marine functional zoning system,discussed internal relation between marine functional zoning system and marine resource allocation,and studied guidance value of marine functional zoning system to allocation of marine resources.

关键词： Marine resources Resource allocation Marine manage

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Precise regulation of the phase transformation for pyrolusite during the reduction roasting process

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 81-90页

作者： Ruofeng Wang Peng Gao Shuai Yuan Yanjun Li yingzhi Liu Cheng Huang School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China National-Local Joint Engineering Research Center of High-efficient Exploitation Technology for Refractory Iron Ore Resources Shenyang 110819China

The mechanism involved in the phase transformation process of pyrolusite (MnO_(2)) during roasting in a reducing atmosphere was systematically elucidated in this study,with the aim of effectively using low-grade complex manganese ore *** to single-factor experiment results,the roasted product with a divalent manganese (Mn^(2+)) distribution rate of 95.30% was obtained at a roasting time of 25 min,a roasting temperature of 700℃,a CO concentration of 20at%,and a total gas volume of 500 mL·min^(-1),in which the manganese was mainly in the form of manganosite (MnO).Scanning electron microscopy and Brunauer–Emmett–Teller theory demonstrated the microstructural evolution of the roasted product and the gradual reduction in the pyrolusite ore from the surface to the core Thermodynamic calculations,X-ray photoelectron spectroscopy,and X-ray diffractometry analyses determined that the phase transformation of pyrolusite followed the order of MnO_(2)→Mn_(2)O_(3)→Mn_(3)O_(4)→MnO phase by phase,and the reduction of manganese oxides in each valence state proceeded simultaneously.

关键词： pyrolusite phase transformation reduction roasting microstructural evolution reaction mechanism

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Efficient elimination of organic contaminants with novel and stable zeolite@MOF layer adsorbents

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Particuology 2021年第5期19卷 74-84页

作者： Jiafei Wu yingzhi Zhu Kunpeng Xue Yan Lu Jiahao Hu Wei Dai Key Laboratory of the Ministry of Education for Advanced Catalysis Materials College of Chemistry and Life ScienceZhejiang Normal UniversityJinhua 321004China Welch Materials(Zhejiang) Inc.Jinhua 321000China

Many metal-organic frameworks(MOFs)trapped in water exhibit instability and small-particle agglomeration issues,which unquestionably constrain their potential applications,such as the capture of organic contaminants(OCs).In this study,four types of micron-sized MOFs(Zn/Cu-BTC,MOF-5,ZIF-8,and UiO-66)were grown within a zeolite-13X support to form millimeter-sized zeolite-13X@MOF composites for the elimination of benzothiophene,methyl orange,and tetracycline from the liquid phase by dynamic adsorption in a *** observed that the 13X@Zn/Cu-BTC exhibited extraordinarily high OC capture capacities as a result of the Zn^(2+) and Cu^(2+) combinative effects of the acid-base ***,the 13X@UiO-66 preserved its structural integrity when immersed in water for 15 days,in contact with boiling water for 12 h,and in both strong acidic and basic aqueous ***,the OC capture abilities of the 13X@UiO-66 only underwent a slight change after the fifth *** work provides new method for the design of desirable millimeter-sized zeolite@MOFs,thereby advancing their practical application for OC capture.

关键词： Zeolite MOFs Adsorption Organic contaminants

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Understanding the roles of Ti on the structure and electrochemical performances of Li2Ru1-xTixO3 cathode materials for Li-ion batteries

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Journal of Energy Chemistry 2019年第6期28卷 9-16页

作者： Hu Zhao Yanchao Shi Li Xue yingzhi Cheng Zhongbo Hu Xiangfeng Liu College of Materials Science and Optoelectronic Technology University of Chinese Academy of SciencesBeijing 100049China Inner Mongolia Synthetic Chemical Institute Hohhot 010072Inner MongoliaChina School of Chemical Engineering Shandong University of TechnologyZibo 255049ShandongChina

The lattice doping has been widely used to improve the electrochemical performances of Li-rich cathode materials but the roles of the introduced foreign atoms are still not very ***,a series of Li2Ru1-xTixO3 solid solutions have been synthesized and the roles of Ti doping on the structural and electrochemical properties of Li2RuO3 have been comprehensively *** Rietveld refinement exhibits that the interlayer spacing gradually shortens with increasing Ti *** shrinkage is favorable to the layered structure stability but increases the lithium diffusion *** measurements show that Li2Ru0.8Ti0.2O3 possesses the best cyclability with 196.9 and 196.1 m Ah g-1for charge and discharge capacity retaining after 90 cycles,*** voltammetry scanning indicates that Ti dopant promotes the formation of more peroxo-or superoxo-like species but reduces the initial coulumbic *** of electrochemical impedance spectroscopy display that Ti doping reduces the charge transfer impedance,which facilitates the lithium-ion diffusion across the electrolyteelectrode interface and improves the electronic ***2Ru0.8Ti0.2O3exhibits the best electrochemical performance owing to the balance among all the factors discussed *** study also offers some new insights into optimizing the electrochemical performances of Li-rich cathode materials through the lattice doping.

关键词： Lithium-ion battery Li-rich cathode Ti doping Rietveld refinement

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Importance Analysis on Subsystem of CNC Lathe Based on TOPSIS

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Journal of Beijing Institute of Technology 2017年第2期26卷 191-196页

作者： Xiaoyan Qi Guixiang Shen yingzhi Zhang Shuguang Sun School of Mechanical Science and Technology Jilin University School of Aircraft and Dynamics Aviation University of Air Force College of Management Science and Engineering Shandong Normal University

An importance analysis model for computer numerical control（CNC）lathe subsystems was *** model was based on technique for order preference by similarity to an ideal solution（TOPSIS）and considered the structure correlation between subsystems and the complete machine,the fault correlation of each subsystem and so *** model can obtain a comprehensive sequencing of subsystems based on their importance to the complete *** lays a theoretical foundation for reliability allocation.

关键词： technique for order preference by similarity to an ideal solution (TOPSIS) importanceanalysis computer numerical control (CNC) lathe influence degree

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