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Exploring the rules of cropland elevation uplift in China

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Journal of Mountain Science 2023年第7期20卷 1824-1841页

作者： yuan Jin-tao CHEN Wan-xu ZENG Jie YE Xin-yue Hubei Key Laboratory of Regional Ecology and Environmental Change School of Geography and Information EngineeringChina Universityof GeosciencesWuhan430074China Department of Landscape Architecture and Urban Planning Texas A&M UniversityCollege StationTX 77840USA

Cropland elevation uplift(CLEU) has recently become a new challenge for agricultural modernization,food security,and sustainable cropland use in *** the rules of CLEU is of great theoretical and practical significance for China’s sustainable agricultural development and rural revitalization ***,existing studies lack in-depth disclosure of multi-scale CLEU evolution rules,making it difficult to support the formulation of specific cropland protection *** analyzed the spatio-temporal evolution and multiscale CLEU in China from 1980 to 2020 using the Lorenz curve,gravity center model,hotspot analysis,and cropland elevation *** results indicated that the center of gravity of cropland moved to the northeast from 1980 to 2000 and then shifted to the *** spatial distribution of cropland became increasingly imbalanced from 1980 to *** change hotspots clustered in the northwest and the northeast,whereas cold-spots were mainly in southeastern *** average elevation of cropland increased by 17.38 m,and the elevation uplift rule in different regions differed evidently across *** 1980 to 2000,all provinces except Xinjiang,Inner Mongolia,Gansu,and Yunnan exhibited CLEU,with Qinghai,Tibet,Beijing,and Guangdong showing the most noticeable *** CLEU can alleviate the shortage of cropland to some ***,without a planning constraint,the CLEU will lead to the increase of ecological risk and food security risk.

关键词： Cropland Elevation uplift rules Multi-scale Elevation spectrum China

Adaptive 3D Edge-Preserving Smoothing De-noise Method and Its Application

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石油地球物理勘探 2009年第A2期44卷 66-71页

作者： Fan tao-yuan Yang Chang-chun Key Laboratory of Geotectonic Movement & Geohazard Institute of Geomeehanics Chinese Academy of Geological Sciences Beijing 100081 China. Institute of Geology and Geophysics Chinese Academy of Science Beijing 100029 China

Unraveling the contribution of Co(IV)and free radicals in Co^(2+)-activated Peroxymonosulfate process:Reaction mechanism,degradation pathway,and DFT calculation

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Emerging Contaminants 2024年第1期10卷 60-71页

作者： tao yuan Yueyuan Zhao Yujiao An Xiaowan Li Gansu Key Laboratory for Environmental Pollution Prediction and Control College of Earth and Environmental SciencesLanzhou UniversityLanzhouGansu730000PR China

The Co^(2+)and Peroxymonosulfate(PMS)reaction is a highly regarded advanced oxidation process(AOP)that has been extensively *** consensus regarding the relative contribution of reactive species in the Co2+/PMS system under different pH conditions has not been *** this study,quenching experiments and electron spin resonance(ESR)tests demonstrated the coexistence of Co(IV),sulfate radical(SO_(4)^(•-)),hydroxyl radical(•OH),and singlet oxygen(1O2),and there fell to CBZ degradation were Co(IV)>SO_(4)^(•-)->•OH≈1O2 in the optimal conditions,where almost 100%of CBZ was degraded in the Co2+/PMS system within 30 ***,Cl−would suppress the formation of Co(IV),SO_(4)^(•-),and•OH but enhance the yield of 1O2,thereby showing a trend of inhibiting CBZ *** probe compound used in this study was Methyl Phenyl Sulfoxide(PMSO),while methyl phenyl sulfone(PMSO_(2))as the indicator of Co(IV),the generation efficiency of PMSO_(2)(η'[PMSO_(2)])increased with reaction time and reached 70%–98%at 40 min at all set pH values(3,4,6,and 8).These results suggest that Co(IV)played a significant role in the Co^(2+)/PMS system and its importance became more pronounced as the reaction *** probe and SO_(4)^(•-)quantification experiments jointly revealed that Co(IV)had the greatest performance at pH 4,and compared to other pH values,SO_(4)^(•-)had the largest contribution in the initial stage of the reaction at pH *** Ecological Structure Activity Relationships(ECOSAR)software was utilized to predict the toxicity of the degradation ***,luminescent bacteria experiments were conducted to assess the acute toxicity of the reaction *** results of these experiments demonstrated that the Co^(2+)/PMS process exhibited a remarkable ability to detoxify the solution.

关键词： Co(IV) Peroxymonosulfate DFT calculation Toxicity assessment

Optimization of reaction conditions for the electroleaching of manganese from low-grade pyrolusite

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International Journal of Minerals,Metallurgy and Materials 2015年第11期22卷 1121-1130页

作者： Xing-ran Zhang Zuo-hua Liu Xing Fan Xin Lian Chang-yuan tao College of Chemistry and Chemical Engineering Chongqing University Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization

In the present study, a response surface methodology was used to optimize the electroleaching of Mn from low-grade pyrolusite. Ferrous sulfate heptahydrate was used in this reaction as a reducing agent in sulfuric acid solutions. The effect of six process variables, including the mass ratio of ferrous sulfate heptahydrate to pyrolusite, mass ratio of sulfuric acid to pyrolusite, liquid-to-solid ratio, current density, leaching temperature, and leaching time, as well as their binary interactions, were modeled. The results revealed that the order of these factors with respect to their effects on the leaching efficiency were mass ratio of ferrous sulfate heptahydrate to pyrolusite 〉 leaching time 〉 mass ratio of sulfuric acid to pyrolusite 〉 liquid-to-solid ratio 〉 leaching temperature 〉 current density. The optimum conditions were as follows： 1.10：1 mass ratio of ferrous sulfate heptahydrate to pyrolusite, 0.9：1 mass ratio of sulfuric acid to pyrolusite, liquid-to-solid ratio of 0.7：1, current density of 947 A/m^2, leaching time of 180 min, and leaching temperature of 73°C. Under these conditions, the predicted leaching efficiency for Mn was 94.1%; the obtained experimental result was 95.7%, which confirmed the validity of the model.

关键词： pyrolusite manganese ore treatment electroleaching reaction conditions optimization

Node dynamic relaxation method： principle and application

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Frontiers of Materials Science 2011年第2期5卷 179-195页

作者： Hong-yuan FANG tao WANG Jun-Feng HU Jian-Guo YANG State Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China

Two main methods, inactive eiement method and quiet element method, to simulate the process of multilayer ：and multipass welding：were reviewed, and the shortcomings of both methods were diScussed as well Based on these analyses, a method called node dynamic relaxation method was put into forward to simulate the multilayer and multipass welding process, and the principle and application of this method were discussed in detail. The simulating results show that using the node dynamic relaxation method can decrease mesh distortion, improve calculation efficiency, and obtain good simulation results. This method can also be used in the field of simulation addition or removing materials in finite element analysis.

关键词： inactive element methodl quiet element methodl node dynamic relaxation method multilayer and multipass Welding finite element analysis (FEA)

Carbon Isotope Excursions and Paleo-Oceanography of the Ordovician–Silurian Boundary Carbonate Rocks from the Xainza Area, Tibet

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Acta Geologica Sinica(English Edition) 2018年第5期92卷 2052-2054页

作者： yuan tao YI Haisheng ZHANG Shuai CAI Zhanhu LI Gaojie Sinopec Exploration Company Chengdu 610041 China Institute of Sedimentary Geology Chengdu University of Technology Chengdu 610059 China Minmetals Exploration & Development Co. LTD Beijing 100010 China College of Earth Sciences Chengdu University of Technology Chengdu 610059 China

Objective The Ordovician–Silurian transitional period is a special time when the global paleo-environment changed *** witnessed the first mass extinction as of Phanerozoic period and glaciations that occurred frequently at a large scale in a very short time,which has thus attracted much attention among geoscientists at home and abroad.

关键词： Carbon Isotope Excursions and Paleo-Oceanography of the Ordovician Silurian Boundary Carbonate Rocks from the Xainza Area Tibet GM

Synthesis of (4S)-4-Carboxyl-1-oxoperoxovanatranes

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Chinese Chemical Letters 1999年第2期10卷 105-106页

作者： Chun yuan tao Ping YAN(Jiujiang Teachers’ College, Jiangxi 332000) Jiujiang Teachers' College Jiangxi 332000 China

(4S)-4-Carboxyl-1-oxoperoxovanatrane and (4S)-3-methyl-4-carboxyl-1-oxoperoxovanatrane were synthesized from the reaction of potassium vanadate. hydrogen peroxide with L-N, N-bis (2-hydroxyethyl) serine or L-N. N-bis ... 详细信息

关键词： (4S)-4-carboxyl-1-oxoperoxovanatranes synthesis chirality

Forecasting conductivities of LiBOB-EC/DEC electrolytes by the mass triangle model

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International Journal of Minerals,Metallurgy and Materials 2009年第4期16卷 463-467页

作者： Jia-yuan Huang Bi-tao Yu Fu-shen Li Wei-hua Qiu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Conductivities of lithium bis（oxalato）borate （LiBOB）-ethyl carbonate （EC）/diethyl carbonaten （DEC） electrolytes at 25℃ and 50℃ were studied. The electrolyte component with the highest conductivity at each temperature was obtained through changing the concentration of LiBOB and the ratio of EC/DEC. The mass triangle model was applied to calculate the conductivity of Li- BOB-EC/DEC ternary system at 25℃ and 50℃. The results show that the calculated and experimental results have reached a good agreement. Therefore, it is expected that the experimental work can be vastly reduced by introducing the mass triangle model.

关键词： lithium bis(oxalato)borate (LiBOB) electrolyte conductivity mass triangle model

Role of primary Zr-rich particles on microstructure and magnetic properties of 2:17-type Sm-Co-Fe-Cu-Zr permanent magnets

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Journal of Materials Science & Technology 2020年第18期52卷 73-81页

作者： tao yuan Xin Song Xianglong Zhou Wentao Jia Munzali Musa Jingdong Wang Tianyu Ma Frontier Institute of Science and Technology State Key Laboratory for Mechanical Behavior of Materialsand MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed MatterXi'an Jiaotong UniversityXi'an710049China The Southwest Applied Magnetism Research Institute Mianyang621000China

Trace Zr addition is essential for achieving desired cellular nanostructure and large coercivity in the pinning-controlled 2:17-type Sm-Co-Fe-Cu-Zr magnets that have served as the strongest high temperature permanent magnets for over 40 ***,accompanying this is the formation of Zr-rich particles that may deteriorate the hard magnetic *** the formerly-reported 1:3R Zr-rich platelets,in this work,1–2μm sized Zr6(Co,Fe)23(6:23)particles(Fm 3 m)and 100–200 nm sized 1:3R Zr-rich particles were also found based on combined structural identifications and element mapping *** such particles,the desired 1:5H cell wall precipitates that provide the strongest pinning force of magnetic domain wall motions are rare,forming the precipitate-free-zones(PFZs).The 1:5H-PFZs and the soft magnetism of both 6:23 and 1:3R Zr-rich particles act as local weak pinning points,which are unfavorable to retain the large magnetization in strong opposite fields and lead to poor *** observed in a Sm25Co45.9Fe19.5Cu5.6Zr4.0(wt.%)magnet,the co-existence of such Zr-rich particles and the associated 1:5H-PFZs leads to a pretty low squareness factor of only 52.89%given the large coercivity of 29.04 *** findings suggest that careful controlling the Zr content and avoiding its aggregation to form harmful 6:23 and 1:3R Zr-rich particles are essential for achieving high squareness as well as large energy product in the Sm-Co-Fe-Cu-Zr permanent magnets.

关键词： Permanent magnets Sm-Co alloys Microstructure Precipitates