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A new process of extracting vanadium from stone coal

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International Journal of Minerals,Metallurgy and Materials 2010年第4期17卷 381-388页

作者： Yan-hua liu Chao Yang Pei-you li shi-qi li Metallurgical and Ecological Engineering School University of Science and Technology Beijing Beijing 100083 China Beijing Nengtai Environmental Protection Group Corp Beijing 100022 China

A new process of extracting vanadium from the stone coal vanadium ore in Fangshankou, Dtmhuang area of Gansu Province, China was introduced. Various leaching experiments were carried out, and the results show that the vanadium ore in Fangshankou is difficult to process due to its high consumption of acid and the high leaching rate of impurities. However, the leaching rate can be up to 80% and the content of V2O5 in the residue can be between 0.22%-0.25% in the process of ore fme grinding→oxidation roasting→mixing and ripening→aqueous leaching→P2O4 solvent extraction→sulfuric acid stripping→oxidation and precipitation→decomposition by heat. Also, the quality of flaky V205 produced by this process can meet the requirements of GB3283--87. The total leaching rate of vanadium is 70%. Also, three types of wastes are easy to treat. The vanadium extraction process is better in relation to the aspect of environmental protection than the sodium method.

关键词： stone coal vanadium extraction leaching solvent extraction V2O5

Ferronickel enrichment by fine particle reduction and magnetic separation from nickel laterite ore

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International Journal of Minerals,Metallurgy and Materials 2014年第10期21卷 955-961页

作者： Xiao-hui Tang Run-zao liu li Yao Zhi-jun Ji Yan-ting Zhang shi-qi li School of Metallurgical and Ecological Engineering University of Science and TechnologyBeijing Hebei Iron and Steel Co. Ltd. Tangshan Branch Tianjin Pipe Group Co. Ltd.

Ferronickel enrichment and extraction from nickel laterite ore were studied through reduction and magnetic separation. Reduction experiments were performed using hydrogen and carbon monoxide as reductants at different temperatures （700-1000℃）. Magnetic separa- tion of the reduced products was conducted using a SLon-100 cycle pulsating magnetic separator （1.2 T）. Composition analysis indicates that the nickel laterite ore contains a total iron content of 22.50wt% and a total nickel content of 1.91wt%. Its mineral composition mainly con- sists of serpentine, hortonolite, and goethite. During the reduction process, the grade of nickel and iron in the products increases with in- creasing reduction temperature. Although a higher temperature is more favorable for reduction, the temperature exceeding 1000℃ results in sintering of the products, preventing magnetic separation. After magnetic separation, the maximum total nickel and iron concentrations are 5.43wt% and 56.86wt%, and the corresponding recovery rates are 84.38% and 53.76%, respectively.

关键词： laterites ore reduction magnetic separation thermodynamics fine particle metallurgy

PCR-DGGE Analysis of Nematode Diversity in Cu-Contaminated Soil

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Pedosphere 2008年第5期18卷 621-627页

作者： WANG shi-Bin li qi liANG Wen-Ju JIANG Yong JIANG Si-Wei Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang110016 （China）.

A wheat pot experiment was conducted under greenhouse conditions to assess the effect of copper contamination on soil nematode diversity by polymerase chain reaction-denaturing gradient gel electrophoresis （PCR-DGGE） method and morphological analysis. The soil was treated with CuSO4.5H2O at the following concentrations： 0, 50, 100, 200, 400, and 800 mg kg^-1 dry soil, and the soil samples were collected at wheat jointing and ripening stages. Nematode diversity index （H′） from morphological analysis showed no difference between the control and the treated samples in either of the sampling dates. At the wheat ripening stage, nematode diversity obtained by the PCR-DGGE method decreased noticeably in the Cu800 treatment in comparison with the control. With optimization of the method of nematode DNA extraction, PCR-DGGE could give more information on nematode genera, and the intensity of the bands could reflect the abundance of nematode genera in the assemblage. The PCR-DGGE method proved promising in distinguishing nematode diversity in heavy metal coritaminated soil.

关键词： copper contamination morphological analysis nematode diversity PCR-DGGE

The Relationship between Pendant Phosphate Groups and Mechanical Properties of Polyisoprene Rubber

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Chinese Journal of Polymer Science 2021年第4期39卷 465-473,I0006页

作者： shi-qi li Mao-Zhu Tang Cheng Huang Rong Zhang Guang-Su Huang Yun-Xiang Xu College of Polymer Science&Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China

It is still a great challenge to mimic the structure and function of natural rubber by introducing polar components into synthetic *** order to explore the function of phosphate groups on the mechanical properties of polyisoprene rubber,a terminally functionalized compound(PIP-P)containing phosphate groups was synthesized and further vulcanized to prepare the model compound *** analyzing the test results,it was found that these phosphate groups formed polar aggregates in non-polar polyisoprene rubber matrix,serving as an additional dynamic cross-linking sites,which increases the cross-linking density and improves mechanical *** influence of the phosphate groups on the strain-induced crystallization(SIC)was further investigated via synchrotron wide-angle X-ray diffraction(WAXD)*** phosphate group aggregates not only reduced the onset strain of SIC,but also slowed down the molecular chain mobility,which hinder the crystal lateral *** above results help us to gain a deeper understanding for the function of phosphate groups in the formation of"naturally occurring network"and guide the molecular design of next generation polyisoprene rubber.

关键词： Phosphate groups Strain-induced crystallization Naturally occurring network Natural rubber

Promoted Comprehensive Properties of Polyisoprene Rubber with Extremely High Fatigue Resistance Enabled by Oligopeptide Aggregates

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Chinese Journal of Polymer Science 2023年第8期41卷 1250-1260,I0008页

作者： Yu He Ran Xu Rong Zhang Chang-Cheng Wang shi-qi li Jian Cao Mao-Zhu Tang Yun-Xiang Xu College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China

For decades,the preparation of polyisoprene rubber that can match the comprehensive properties of natural rubber(NR)has been *** sacrificial bonds have been used to promote the strength and toughness of rubbers,little is known about their effects on fatigue resistance,which is important in dynamic ***,terminal block and randomly functionalized polyisoprene rubbers tethered with di-alanine,tri-alanine and tetra-alanine were *** results showed that the flow activation energy,aggregates ordering and energy dissipation of the hydrogen-bonded aggregates increase with the elongation of oligopeptide length(XA,X=2,3,4),therefore resulting in enhanced mechanical strength and toughness of corresponding ***,the tear strengths are barely affected by oligopeptide lengths in block samples,but promoted from dipeptide to tetrapeptide in random samples,probably due to the well dispersed oligopeptide *** importantly,it is found that the tight binding aggregates of oligopeptides are critical for the excellent fatigue resistance,which is absent in polyisoprene and natural *** loose aggregates dissociate and recombine repeatedly under cyclic loading and the tight aggregates keep the network integrated and ***,the largest hysteresis of PIP-4A-V with the longest oligopeptide length give the lowest heat generation,which is contrary to the traditional sacrificial ***,the oligopeptide aggregates have repeatable energy dissipation properties and cycle life comparable to or even surpassing those of the linked proteins in NR,resulting in similar tensile strength,fracture toughness,and better fatigue resistance relative to *** deep insight on the role of oligopeptide aggregates is very useful for the engineering rubbers served in dynamic environments.

关键词： Polyisoprene Hydrogen bonding Oligopeptides Fatigueresistance

Trends and prevalence of eating disorders in children and adolescents

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World Journal of Psychiatry 2024年第12期14卷 1815-1826页

作者： qi Chen Shu Huang Jie-Yu Peng Huan Xu Ping Wang Xiao-Min shi shi-qi li Rui Luo Wei Zhang Lei shi Yan Peng Xiao-Hong Wang Xiao-Wei Tang Department of Gastroenterology The Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina Department of Gastroenterology Lianshui People’Hospital of Kangda College Affiliated to Nanjing Medical UniversityHuaian 223499Jiangsu ProvinceChina Department of Gastroenterology Xuzhou Central HospitalXuzhou Clinical School of Xuzhou Medical UniversityXuzhou 221000Jiangsu ProvinceChina

BACKGROUND Eating disorders(EDs)have increasingly become a public health problem globally,especially among children and *** To estimate the burden of EDs in children and adolescents(ages 5-19 years)at the global,regional,and national *** Retrieved from Global Burden of Disease Study 2019 for EDs,including anorexia nervosa and bulimia nervosa,we extracted the disability-adjusted life years(DALYs)and prevalence rates with 95%uncertainty intervals between *** temporal trends of the DALYs and prevalence rates of EDs were assessed according to the estimated annual percentage *** In our study,we found that the burden of EDs continuously increased globally from 1990 to *** females accounted for more EDs cases,the burden of EDs in males had a greater ***,the burden of EDs was associated with the high sociodemographic index(SDI)over the past 30 years and the human development indexes in *** EDs,predominantly in high-income countries,are rising globally,especially in Asia,highlighting the need for resource planning and medical policy prioritization across all SDI quintiles.

关键词： Eating disorders Global Burden of Disease Study 2019 Children and adolescents Epidemiology Prevalence

Analysis of chemical composition of precipitation in a typical background site

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Journal of Environmental Sciences 1998年第3期10卷 70-78页

作者： liu Jiaqi, shi liliYunnan Provincial Environmental Monitoring Center Station, Kunming 650034, China

background precipitation in lijiang, China was investigated. Results showed that the chemical composition of atmospheric background precipitation mainly comes from fly ash and continental atmospheric transfer, and does not have any obvious correlation with oceanic aerosol, taking Amsterdam in the Pacific Ocean and St. Georges in the Atlantic Ocean and Katherine, Australia as examples for analysing. 

关键词： fly ash background precipitation chemical composition. 

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小流域综合治理的国内外进展综述与思考

北京林业大学学报 2017年第8期39卷 1-8页

作者：齐实李月北京林业大学水土保持学院、水土保持国家林业局重点实验室、北京市水土保持工程技术研究中心、林业生态工程教育部工程研究中心

小流域综合治理是一项复杂而艰巨的任务,需综合考虑经济、社会、生态、环境等诸多因素。结合我国目前的小流域治理思路、综合规划及治理要求,本文梳理了国内外小流域综合治理的发展过程,阐述了部分发达国家(美国、欧洲、日本)和发展中国... 详细信息

小流域综合治理是一项复杂而艰巨的任务,需综合考虑经济、社会、生态、环境等诸多因素。结合我国目前的小流域治理思路、综合规划及治理要求,本文梳理了国内外小流域综合治理的发展过程,阐述了部分发达国家(美国、欧洲、日本)和发展中国家(印度、尼泊尔、非洲)小流域治理的思路、技术及模式等,分析了小流域综合治理的特点以及主要经验、存在和需要进一步解决的问题,提出了在新时期我国小流域综合治理的一些思考和展望:在当前的小流域综合治理中应注重与经济、政治、文化、社会建设的紧密结合;针对不同区域的生态经济特征,治理需遵循因地制宜、适度治理的原则;应适应社会经济的发展,不断调整综合治理的对象、内容和措施。

关键词：国际小流域综合治理

High-temperature oxidation behavior and degradation mechanism of chromium-coated zirconium alloy cladding: a review

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Tungsten 2025年第1期7卷 50-70页

作者： Yi li Bei-qi Wang Xin-Yin Zhang shi-Jie Wang Cong-Yi li Hui-Long Yang Ran-Ran Su Tong liu School of Mechanical Engineering Shanghai Jiao Tong University College and Graduate School of Arts and Sciences University of Virginia Global Institute of Future Technology Shanghai Jiao Tong University

Accident-tolerant fuels(ATF) have been extensively studied to reduce the production rate and total amount of heat and hydrogen generated from high-temperature steam oxidation during severe ***-coated zirconium alloy cladding has become one of the most promising candidates for ATF because of its excellent corrosion and oxidation *** paper provides a comprehensive overview of the research progress on oxidation behaviors and degradation mechanisms in chromium-coated zirconium alloy cladding under high-temperature *** techniques to strengthen the oxidation resistance are highlighted and ***,challenges and opportunities for various future directions are addressed.

关键词： Accident-tolerant fuel Chromium coating Degradation mechanism High-temperature oxidation behavior Zirconium alloy cladding