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Cobalt-doped tiO_(2)@C hierarchical nanocomposites derived from ti_(3)C_(2) MXene as cathodes for hybrid magnesium-lithium batteries

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Nano Research 2024年第1期17卷 253-261页

作者： Xiaohui Li Yakun Tang Lang Liu Yue Zhang yang Gao Mao Qian Wenjie Ma State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of ChemistryXinjiang UniversityUrumqi 830017China

tiO_(2)has been explored in hybrid magnesium-lithium batteries(HMLBs)due to the advantages of low self-discharge and small volume expansion during ion ***,how to improve the inherently low ionic and electrical conductivity of tiO_(2)is the problem that needs to be *** this work,a smart strategy is adopted to prepare cobalt-doped tiO_(2)@C(Co^(4+)-tiO_(2)@C)hierarchical nanocomposite derived from Co(II)(OH)n@*** with tiO_(2)@C(without cobalt doping),Co^(4+)-tiO_(2)@C shows the highest specific capacity(154.7 mAh·g^(-1)at 0.1 A·g^(-1)after 200 cycles)and extraordinary rate performance in *** excellent electrochemical performance of Co4+-tiO_(2)@C is ascribed to the synergistic effect of the hierarchical structure and *** experimental results and density functional theory(DFT)calculation reveal that the cobalt-doping has effectively improved the electronic conductivity and reduced the Li+migration *** work provides a new insight to design tiO_(2)-based cathode materials with high-performance in HMLBs.

关键词： ti_(3)C_(2)MXene tiO_(2) hybrid magnesium-lithium batteries hierarchical structure cobalt-doping

Martensite decomposition under thermal-mechanical coupling conditions to fabricate an ultrafine-grained ti6Al4Mo4Zr1W0.2Si alloy

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Journal of Materials Science & Technology 2024年第1期168卷 157-168页

作者： Taoyu Zhou Jiuxu yang Nan Li Hao Sun Bohua Zhang Zibo Zhao Qingjiang Wang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

The fabrication of ultrafine-grained microstructures(grain size below 1μm)in titanium alloys is beneficial for improving their mechanical properties at room temperature and medium tempera-tures(400-550°C).However,a long-standing challenge involves the low-cost manufacturing of bulk ultrafine-grained titanium *** this work,we developed a facile strategy through martensite de-composition at thermal-mechanical coupling conditions,to fabricate an equiaxed microstructure in a ti6Al4Mo4Zr1W0.2Si model alloy with an averageαgrain size of 315±62 *** formation of the ultrafine-grained microstructure was because the lattice strain stored in the martensitic initial mi-crostructure enhanced the nucleation rate of dynamic recrystallization,meanwhile,the pinning role of martensite decomposition productsβand(ti,Zr)_(5)Si_(3)phases suppressed grain coarsening at high *** to conventional(α+β)alloys,the tensile strength of this alloy improved by 20%-30%at both room temperature and 550°C,without decreasing its *** situ SEM observations revealed that the ultrafine-grained microstructure would not only suppress dislocation motions but also contribute to the homogenous deformation in the matrix of the material,therefore,it resulted in higher mechanical *** research results may be of great significance to the development of next-generation aviation titanium alloys.

关键词： Ultrafine-grained titanium alloy In situ observation Deformation mechanism Thermostability

中国7城市2乡镇3～12岁儿童血矿物质水平调查

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北京大学学报（医学版） 2014年第3期46卷 379-382页

作者：马德福张玉梅王培玉杨媞媞拓亚生庆海北京大学公共卫生学院社会医学与健康教育学系北京100191 北京大学公共卫生学院营养与食品卫生学系北京100191 内蒙古蒙牛乳业(集团)股份有限公司乳制品研发中心呼和浩特011500

目的：了解中国不同城市和乡镇3～12岁儿童的血矿物质水平，并探讨相关影响因素。方法：采用多阶段分层随机整群抽样方法在北京、广州等7个城市和两个乡镇（平原、山区）各随机抽取1所幼儿园和1所小学，并抽取幼儿园小班、中班、大班，... 详细信息

目的：了解中国不同城市和乡镇3～12岁儿童的血矿物质水平，并探讨相关影响因素。方法：采用多阶段分层随机整群抽样方法在北京、广州等7个城市和两个乡镇（平原、山区）各随机抽取1所幼儿园和1所小学，并抽取幼儿园小班、中班、大班，小学两个年级（二年级和五年级）各1个班，将班内所有健康儿童作为研究对象抽血检测其血钙、镁、铅、铁、铜、锌的含量。结果：共调查儿童1842人，钙、镁、铅、铁、铜、锌的平均值都处于标准值范围。男童的血铅含量显著高于女童，不同年龄组之间血矿物质含量存在显著差异，学龄前儿童的血钙含量和血铜含量显著高于学龄儿童，而学龄儿童的血铅含量、血铁含量和血锌含量显著高于学龄前儿童。分别有高达35．5％和39．6％的儿童存在不同程度的缺铁和缺锌，不同年龄组之间，铁缺乏率和锌缺乏率差异均有统计学意义（ P＝0．001），且随年龄的增加而逐渐降低；大于等于3岁、小于4岁组儿童的铁缺乏率和锌缺乏率分别高达47．1％和64．6％；平原乡镇和山区乡镇儿童铁缺乏率显著高于一线城市儿童，而平原乡镇和山区乡镇儿童的锌缺乏率显著低于一、二线城市儿童。结论：目前中国城市和乡镇3～12岁儿童的铁缺乏和锌缺乏状况仍然非常严重，未来儿童营养膳食方面应该重点加强铁和锌方面的干预研究。

关键词：锌铁血清儿童

A mini review on the separation of Al,Fe and ti elements from coal fly ash leachate

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International Journal of Coal Science & Technology 2024年第2期11卷 1-15页

作者： Yuan Shi Fengqi Jiang Rongjiao Wang Sasha yang Xiaofeng Zhu Yingying Shen State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals School of Material Science and EngineeringLanzhou University of TechnologyLanzhou 730050China Department of Chemical and Biological Engineering Monash UniversityWellington RoadClaytonMelbourneVIC 3800Australia

The electricity demand is increasing rapidly with the development of society and ***-fired thermal power plants have become one of the primary sources of electricity generation for ***,coal-fired thermal power plants produce a great amount of by-product coal fly ash every *** fly ash disposal in landfills requires a sizable space and has negative environmental ***,it is crucial to develop new technologies and methods to utilize this enormous volume of solid waste in order to protect the *** this review,the fundamental physical and chemical character-istics of coal fly ash are introduced,and afterward the disposal policies and utilization ways of coal fly ash are discussed to gain a comprehensive understanding of the various ways this *** leaching of valuable metals in coal fly ash and the extraction of metal elements in leachate under different conditions are also ***,the possibility of coal fly ash to serve as a supplementary source for mineral resources is analyzed,providing a basis for its extensive use as a raw material in the metal industry in China and worldwide.

关键词： Coal fly ash Waste utilization Metals extraction

Oxidation Resistance of In Situ Reaction/Hot Pressing Synthesized ti_(2)AlC-20%tiB_(2) Composite at 600-900℃in Air

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 739-748页

作者： Wenting Wang Jingjun Xu Jun Zuo Ke Ma yang Li Guangqi He Meishuan Li Shengyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China

The oxidation behavior and kinetics of ti_(2)AlC-20vol.%tiB_(2) composite at 600-900℃ in air were *** results showed that the oxidation kinetics of the composite followed a logarithmic law within the given temperature range,which indicated that the composites had excellent oxidation *** selective oxidation of Al in ti_(2)AlC was greatly enhanced,which facilitated the formation of a continuous and dense protective layer of Al_(2)O_(3).Meanwhile,the existence of molten B_(2)O_(3) inhibited the outward diffusion of ti and inward diffusion of oxygen,which prevented the growth of anatase tiO_(2) at 600℃ and rutile tiO_(2) at 700-900℃.Therefore,the incorporation of tiB_(2) completely inhibited the abnormally rapid oxidation of bulk ti_(2)AlC at 600℃ and improved its oxidation resistance at 700-900℃.

关键词： MAX phase ti_(2)AlC-tiB_(2)composite Intermediate temperature oxidation Oxidation kinetics

Mechanical Properties and Electronic Structures of M(M=ti,V,Cr,Mn and Fe)Dopedβ-Si_(3)N_(4) from First-Principle

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 639-644页

作者：龙敏黄福祥 XU Liangyu LI Xuemei yang Zhou LENG Yue MEI Shini School of Materials Science and Engineering Chongqing University of TechnologyChongqing 400054China

The structures,mechanical properties and electronic structures of M metals(M=ti,V,Cr,Mn and Fe)dopedβ-Si_(3)N_(4) were investigated by First-principles calculations within *** calculated lattice parameters ofβ-Si_(3)N_(4) were consistent with previous *** cohesive energy and formation enthalpy show that initialβ-Si_(3)N_(4) has the highest structural *** calculated elastic constant and the Voigt-Reuss-Hill approximation indicate that elastic moduli ofβ-Si_(3)N_(4) are slightly reduced by M *** on Poisson’s and Pugh’s ratio,β-Si_(3)N_(4) is a ductile material and the toughness ofβ-Si_(3)N_(4) increases with M doping,and Fe doping exhibited the best *** results of density of states,charge distributions and overlapping populations indicate thatβ-Si_(3)N_(4) has the strong covalent and ionic bond strength between N and Si.

关键词： first-principles β-Si_(3)N_(4) mechanical properties electronic structure

长链非编码RNA-AK017233在乌拉坦诱导的小鼠肺癌组织中低表达（英文）

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中国药理学与毒理学杂志 2014年第2期28卷 168-174页

作者：杨倜李远奇李勋蒋义国广州医科大学化学致癌研究所广东广州510182

目的探寻乌拉坦诱导肺癌形成过程中lncRNA表达的动态变化过程。方法 BALB/c小鼠每周ip给予乌拉坦1 g·kg-1,连续4周,分别在处理后第12周或第24周处死。分离小鼠肺组织,提取RNA。通过长链非编码RNA芯片和定量PCR的方法分析长链非编码RNA-... 详细信息

目的探寻乌拉坦诱导肺癌形成过程中lncRNA表达的动态变化过程。方法 BALB/c小鼠每周ip给予乌拉坦1 g·kg-1,连续4周,分别在处理后第12周或第24周处死。分离小鼠肺组织,提取RNA。通过长链非编码RNA芯片和定量PCR的方法分析长链非编码RNA-AK017233表达。结果与对照组相比,乌拉坦染毒12周后的小鼠肺肿瘤的发生率为85%,每只小鼠平均肿瘤数为2.81±2.04,肿瘤的平均大小为(0.68±0.20)mm;乌拉坦染毒24周后的小鼠肺肿瘤的发生率为100%,每只小鼠平均肿瘤数为6.00±2.07,肿瘤的平均大小为(1.76±1.34)mm。病理检查显示均为肺腺癌。乌拉坦处理的确可以影响小鼠肺组织内的长链非编码RNA表达情况。通过芯片分析,发现以长链非编码RNA-AK017233为代表的26个表达下调的长链非编码RNA,随后通过定量PCR确认长链非编码RNA-AK017233在乌拉坦处理12周诱发的肺腺癌组织中表达水平下调33%,在乌拉坦处理24周诱发的肺腺癌组织中表达水平下调22%。结论长链非编码RNA-AK017233在乌拉坦诱导的肺癌形成过程中始终处于低表达状态。

关键词：长链非编码RNA 肺癌乌拉坦

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宫颈癌术后局部复发的预防与治疗

中国伤残医学 2014年第21期22卷 15-16页

作者：杨黛蒂江苏省宜兴市肿瘤医院江苏宜兴214206

目的：宫颈癌根治术后局部复发因素、预防措施及疗效。方法：将2011年1月～2014年1月在我院治疗的56例宫颈癌术后复发者根据复发部位及病情分为放疗组、放疗化疗组、手术放疗化疗组，分析复发原因并针对性制定预防方法。结果：放疗组患... 详细信息

目的：宫颈癌根治术后局部复发因素、预防措施及疗效。方法：将2011年1月～2014年1月在我院治疗的56例宫颈癌术后复发者根据复发部位及病情分为放疗组、放疗化疗组、手术放疗化疗组，分析复发原因并针对性制定预防方法。结果：放疗组患者复发后1、2、3、5年的生存率分别为81．0％、70．3％、43．2％、32．4％；放疗化疗组患者分别为79．5％、66．7％、38．5％、25．6％。手术放疗化疗组患者分别为65．8％、42．3％、21．1％、5．3％。结论：综合治疗是宫颈癌术后复发有效的治疗方法。

关键词：宫颈癌局部复发手术治疗化疗放疗

诊断性脾切除术对不明原因发热伴脾肿大的临床意义

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中华医学杂志 2006年第48期86卷 3385-3388页

作者：杨志英韩冰杨缇高维生桑新亭段明辉赵永强沈悌中国医学科学院中国协和医科大学北京协和医院肝脏外科 100730 中国医学科学院中国协和医科大学北京协和医院血液科 100730 中国医学科学院中国协和医科大学北京协和医院病理科 100730

目的探讨不明原因发热伴脾肿大行诊断性脾切除术的临床意义及可能的危险因素。方法回顾分析了我院20年来因不明原因发热、脾肿大行剖腹探查加诊断性脾切除术的54例患者的临床资料及病理检查结果，并对可能的危险因素进行分析。结果54例... 详细信息

目的探讨不明原因发热伴脾肿大行诊断性脾切除术的临床意义及可能的危险因素。方法回顾分析了我院20年来因不明原因发热、脾肿大行剖腹探查加诊断性脾切除术的54例患者的临床资料及病理检查结果，并对可能的危险因素进行分析。结果54例患者手术后经病理确诊39例，病理诊断率为72．2％（39／54），其中恶性淋巴瘤32例（59．3％，32／54）。25．9％的（14／54）患者出现手术并发症，并发症发生依次主要为：术后感染、出血、心功能衰竭、肝功能衰竭及膈下积液。9例（16．7％）患者围手术期死亡，死亡原因主要为：严重感染、术后出血、本身疾病恶化、心功能衰竭、肝功能衰竭及猝死。在相关危险因素中，有、无浆膜腔积液组死亡率分别为46．2％和7．5％（P=0．011）；脾脏重量≤500g,500—1500g及≥1500g组围手术期死亡率分别为0％、11．8％、50．0％（后2组比较，P=0．01）；有无黄疸、血三系减少、转氨酶升高及乳酸脱氢酶升高及病程长短与围手术期死亡率无明显相关（P〉0．1）。浆膜腔积液和巨脾是相对独立的影响死亡的因素（P值分别为0．011和0．01；／bY分别为20．4和18．6）。结论不明原因发热伴肝脾肿大患者，在高度怀疑恶性血液病但又不能明确诊断时，剖腹探查及诊断性脾切除术是有意义的方法。合并浆膜腔积液及巨脾者围手术期死亡率增高。

关键词：不明原因发热脾大脾切除术诊断