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直觉模糊软半环的直觉模糊软理想

重庆师范大学学报（自然科学版） 2017年第5期34卷 54-59页

作者：李庆吴春重庆师范大学数学科学学院重庆401331

【目的】通过对半环的研究,使之更好地应用于信息科学等领域。【方法】引入了直觉模糊软半环和直觉模糊软半环的直觉模糊软理想的概念,进行了一系列讨论。【结果】在充分利用各自理论优势的基础上,得到了直觉模糊软半环的直觉模糊软理... 详细信息

【目的】通过对半环的研究,使之更好地应用于信息科学等领域。【方法】引入了直觉模糊软半环和直觉模糊软半环的直觉模糊软理想的概念,进行了一系列讨论。【结果】在充分利用各自理论优势的基础上,得到了直觉模糊软半环的直觉模糊软理想的诸多性质。【结论】对进一步研究半环这一重要代数结构有着积极的意义。

关键词：直觉模糊软集半环软集理想软理想

Additives strategies to improving cycling stability of li metal batteries by modifying electrode electrolyte interphases

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Progress in Natural Science:Materials International 2024年第2期34卷 338-344页

作者： Yuan li Pengfei Huang Chunyu Cui Xiaoyuan Ma li Chen Zekun li linhai li Yuhong Tian School of Biological and Chemical Engineering Guangxi University of Science and Technology School of College of Chemistry and Chemical Engineering Hunan University Isky Future Energy Institute

li metal batteries（LMBs） have attracted much attention due to the ultra-high theoretical capacity of the li metal anode（LMA）.However,the uncontrollable dendrites growth and low coulombic efficiency hinder their practical ***,we explore 3,5-difluoropyridine（2F-BD） as a novel electrolyte additive to enable highperformance *** 2F-BD additive participates in and modifies the solvation structure of li ions by reducing the coordinated number of PF6-at the electrode surface,leading to the formation of a liF and li3N-rich solid electrolyte interphase（SEI）.The liF component increases the robustness of SEI and suppresses the formation of li dendrites,while the li3N component facilitates the transportation and reaction kinetics of li *** a result,the li‖li symmetric cell presents a stable cycling performance of up to 500 h at a current density of 1 mA *** coupling with liFePO4cathode,the obtained full cell achieves high specific capacities of 106.06 mA h g-1and 84.98 mA h g-1at 2.55 mA cm-2and 5.10 mA cm-2,respectively,and maintains a high capacity retention of84.0% after 1000 cycles at 0.13 mA cm-2,with an average cycling CE of 99.58%.

关键词： Electrolyte additive li dendrites li metal batteries liF and li3N-Rich electrode-electrolyte interphase liFePO4 cathode

Bi对Al-18%Si合金微观组织与力学性能的影响

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铸造 2011年第5期60卷 477-480页

作者：兰晔峰郭晶李庆林王强强兰州理工大学材料科学与工程学院甘肃兰州730050 兰州理工大学甘肃省有色金属新材料省部共建国家重点实验室甘肃兰州730050

研究不同的Bi含量对过共晶Al-18%Si合金微观组织与力学性能的影响。试验表明,Al-18%Si-x%Bi(x=1,2,3,4,5)合金中,大部分Bi在基体中以小颗粒状弥散均匀分布,局部出现Bi的聚集;同时,Bi的加入对合金中的共晶硅起到一定的细化作用;随着Bi含... 详细信息

研究不同的Bi含量对过共晶Al-18%Si合金微观组织与力学性能的影响。试验表明,Al-18%Si-x%Bi(x=1,2,3,4,5)合金中,大部分Bi在基体中以小颗粒状弥散均匀分布,局部出现Bi的聚集;同时,Bi的加入对合金中的共晶硅起到一定的细化作用;随着Bi含量的增加,共晶硅组织由粗大针片状变成短杆状,当Bi含量达到3%时,共晶硅转变为均匀分布于基体的蠕点状,当Bi含量为4%或5%时,共晶硅没有进一步的细化。另外,力学性能和摩擦试验研究发现:Al-18%Si-3%Bi合金的抗拉强度由Al-18%Si合金的168 MPa提高为189 MPa,摩擦系数由0.437 2降为0.387 9,磨损量仅为不含Bi的20%。

关键词：过共晶Al-18%Si合金合金元素Bi 微观组织力学性能

Leaching kinetics of fluorine during the aluminum removal from spent li-ion battery cathode materials

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Journal of Environmental Sciences 2024年第4期138卷 312-325页

作者： Shengjie li Jianxin Zhu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

The high content of aluminum(Al)impurity in the recycled cathode powder seriously affects the extraction efficiency of Nickel,Cobalt,Manganese,and lithium resources and the actual commercial value of recycled materials,so Al removal is crucially important to conform to the industrial standard of spent li-ion battery cathode *** this work,we systematically investigated the leaching process and optimum conditions associated with Al removal from the cathode powder materials collected in a wet cathode-powder peeling and recycling production line of spent li-ion batteries(liBs).Moreover,we specifically studied the leaching of fluorine(F)synergistically happened along with the removal process of Al,which was not concerned about in other studies,but one of the key factors affecting pollution prevention in the recovery *** mechanism of the whole process including the leaching of Al and F from the cathode powder was indicated by using NMR,FTIR,and XPS,and a defluoridation process was preliminarily investigated in this *** leaching kinetics of Al could be successfully described by the shrinking core model,controlled by the diffusion process and the activation energy was 11.14 kJ/***,the leaching of F was attributed to the dissolution of liPF6and decomposition of PVDF,and the kinetics associated was described by Avrami *** interaction of Al and F is advantageous to realize the defluoridation to some *** is expected that our investigation will provide theoretical support for the large-scale recycling of spent liBs.

关键词： Al removal F leaching Cathode powder Heating alkali leaching Leaching kinetics

血清Leptin和TNF-α与2型糖尿病视网膜病变的相关关系研究

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眼科新进展 2009年第8期29卷 584-586,590页

作者：李庆雨谷淑颖刘丹盘锦市第一人民医院眼科辽宁省盘锦市124010 盘锦市第二人民医院眼科辽宁医学院附属第一医院眼科辽宁省锦州市121001

目的探讨血清中瘦素(Leptin)、肿瘤坏死因子α(tumornecrosis factor-α,TNF-α)的水平与2型糖尿病视网膜病变发生发展之间的关系。方法对88例2型糖尿病患者(按照糖尿病视网膜病变分级标准,再将其分为3个亚组)及30例健康对照者,采用放... 详细信息

目的探讨血清中瘦素(Leptin)、肿瘤坏死因子α(tumornecrosis factor-α,TNF-α)的水平与2型糖尿病视网膜病变发生发展之间的关系。方法对88例2型糖尿病患者(按照糖尿病视网膜病变分级标准,再将其分为3个亚组)及30例健康对照者,采用放射免疫法测定血清中Leptin和TNF-α,免疫抑制比浊法测定糖化血红蛋白,记录相关的临床和生化指标。结果2型糖尿病视网膜病变组患者血清Leptin水平(10.57±1.84)μg.L-1显著高于无视网膜病变组的(7.90±1.58)μg·L-1(P<0.01);增生性糖尿病视网膜病变组血清Leptin水平(11.66±1.21)μg.L-1显著高于非增生性糖尿病视网膜病变组的(9.56±1.75)μg.L-1(P<0.01)及无视网膜病变组的(7.90±1.58)μg·L-1(P<0.01)。2型糖尿病视网膜病变组患者血清TNF-α水平(60.45±13.33)pmol·L-1显著高于无视网膜病变组的(39.97±8.38)pmol·L-1(P<0.01);增生性糖尿病视网膜病变组血清TNF-α水平(69.93±10.86)pmol.L-1显著高于非增生性糖尿病视网膜病变组的(51.60±8.47)pmol·L-1(P<0.01)及无视网膜病变组(39.97±8.38)pmol·L-1(P<0.01)。血清Leptin水平与病程、糖化血红蛋白、体质量指数成正相关(r=0.639,P<0.01;r=0.260,P<0.05;r=0.468,P<0.01);血清TNF-α与病程、空腹血糖、体质量指数成正相关(r=0.680、0.355、0.299,P<0.01),与收缩压、舒张压成正相关(r=0.281、0.234,P<0.05),与高密度脂蛋白胆固醇成负相关(r=-0.423,P<0.01)。血清Leptin、TNF-α水平成正相关(r=0.660,P<0.05)。结论2型糖尿病合并糖尿病视网膜病变患者血清Leptin、TNF-α水平增高;随着糖尿病视网膜病变程度的加重,血清中的Leptin、TNF-α水平也逐渐升高,提示其与糖尿病视网膜病变,特别是糖尿病视网膜病变的严重程度相关。

关键词：糖尿病视网膜病变瘦素肿瘤坏死因子α 2型糖尿病

SEI/dead li-turning capacity loss for high-performance anode-free solid-state lithium batteries

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Journal of Energy Chemistry 2024年第9期96卷 145-152页

作者： Qianwen Yin Tianyu li Hongzhang Zhang Guiming Zhong Xiaofei Yang Xianfeng li Division of Energy Storage Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Long-Duration and Large-Scale Energy Storage Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Laboratory of Advanced Spectro-Electrochemistry and lithium-Ion Batteries Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Anode-free solid-state lithium metal batteries(AF-SSLBs)have the potential to deliver higher energy density and improved safety beyond lithium-metal ***,the unclear mechanism for the fast capacity decay in AF-SSLBs,either determined by dead li or solid electrolyte interface(SEI),limits the proposal of effective strategies to prolong cycling *** clarify the underlying mechanism,herein,the evolution of SEI and dead li is quantitatively analyzed by a solid-state nuclear magnetic resonance(ss-NMR)technology in a typical liPF6-based polymer *** results show that the initial capacity loss is attributed to the formation of SEI,while the dead li dominates the following capacity loss and the growth rate is 0.141 mA h cm^(−2)cycle−*** reduce the active li loss,the combination of inorganic-rich SEI and self-healing electrostatic shield effect is proposed to improve the reversibility of li deposition/dissolution behavior,which reduces the capacity loss rate for the initial SEI and following dead li generation by 2.3 and 20.1 folds,*** a result,the initial Coulombic efficiency(ICE)and stable CE increase by 15.1%and 15.3%in li-Cu cells,which guides the rational design of high-performance AF-SSLBs.

关键词： Solid-state lithium batteries Solid-state NMR Anode-free SEI Dead li

Theoretical Design of Defects as a Driving Force for Ion Transport in li_(3)OBr Solid Electrolyte

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Energy & Environmental Materials 2024年第3期7卷 143-153页

作者： Xingyun Luo Yanlu li Xian Zhao State Key Lab of Crystal Materials and Institute of Crystal Materials Shandong UniversityJinan 250100China Center for Optics Research and Engineering Shandong UniversityQingdao 266237China

Due to ever-increasing concerns about safety issues in using li ionic batteries,solid electrolytes have extensively *** li-rich antiperovskite li_(3)OBr has been considered as a promising solid electrolyte candidate,but it still suffers challenges to achieve a high ionic conductivity owing to the high intrinsic symmetry of the crystal ***,we presented a design strategy that introduces various point defects and grain boundaries to break the high lattice symmetry of li_(3)OBr crystal,and their effect and microscopic mechanism of promoting the migration of li-ion were explored *** has been found that li_(i)are the dominant defects responsible for the fast li-ion diffusion in bulk li_(3)OBr and its surface,but they are easily trapped by the grain boundaries,leading to the annihilating of the Frenkel defect pair V'_(li)+li_(i),and thus limits the V'_(li)diffusion at the grain *** V_(Br)defect near the grain boundaries can effectively drive V'_(li)across the grain boundary,thereby converting the carrier of li^(+)migration from li,in the bulk and surface to V'_(li)at the grain boundary,and thus improving the ionic conductivity in the whole li_(3)OBr *** work provides a comprehensive insight into the li^(+)transport and conduction mechanism in the li_(3)OBr *** opens a new way of improving the conductivity for all-solid-state li electrolyte material through the defect design.

关键词： defects density functional theory ionic migration solid electrolyte

Highly polar CoP/Co_(2)P heterojunction composite as efficient cathode electrocatalyst for li-air battery

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Chinese Chemical Letters 2024年第9期35卷 486-490页

作者： Miaomiao li Mengwei Yuan Xingzi Zheng Kunyu Han Genban Sun Fujun li Huifeng li Beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal UniversityBeijing 100875China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjin 300071China Center for Advanced Materials Research Beijing Normal UniversityZhuhai 519087China

In order to advance the commercialization of rechargeable li-air batteries,it is of importance to explore cathode catalyst with efficient catalytic *** metal oxides have poor electrical conductivity,while cobalt phosphide has excellent electrical conductivity and large specific surface ***,its application in organic li-air batteries has been much less studied,and the electrocatalytic activity desires to be further ***,CoP/Co_(2)P heterojunction composite with higher polarity was *** discharge product of high-polarity CoP/Co_(2)P had a new porous box-like morphology,which was easy to be decomposed and exposed more active *** highly polar CoP/Co_(2)P heterostructure composite had homogeneous pores,the synergistic effect existed between CoP and Co_(2)P,and the discharge product was porous box mixed with li_(2)O_(2)and liOH,which made CoP/Co_(2)P achieve high specific capacity of14632 m Ah/g and cycle stably 161 times when used as air electrode cathode *** work furnished a thought for the construction of cathode catalysts with efficient catalytic activity for li-air batteries.

关键词： li-air battery Cathode catalyst CoP/Co_(2)P Heterojunction structure High polarity

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酶催化茶油转酯化反应制备生物柴油的研究

现代化工 2008年第S2期28卷 153-155页

作者：陈敏刘幽燕庾乐李青云广西大学化学化工学院广西南宁530004

研究了茶油在脂肪酶Novozym 435催化下的转酯化反应,考察了几种直链和支链醇对转酯化反应的影响。选择甲醇作为酰基受体,最佳用量为醇油摩尔比3∶1。通过在反应体系中加入硅胶的策略来提高转酯化反应速率和最终转化率,当硅胶用量为0.8 g... 详细信息

研究了茶油在脂肪酶Novozym 435催化下的转酯化反应,考察了几种直链和支链醇对转酯化反应的影响。选择甲醇作为酰基受体,最佳用量为醇油摩尔比3∶1。通过在反应体系中加入硅胶的策略来提高转酯化反应速率和最终转化率,当硅胶用量为0.8 g/g,30 h的转化率从原来的40%提高到90%。在最佳条件下进行批式反应,酶重复使用15批次后活性无明显下降。

关键词：生物柴油茶油酶催化转酯化