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Study on metal recovery process and kinetics of oxidative leaching from spent LiFePO_(4)Li-batteries
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作者 Xiaoming Zhang Wen Xie +5 位作者 Xiaolei Zhou Wenjie Zhang Jiawei Wen Xin Wang Guoyong Huang Shengming Xu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期94-102,共9页
A green environmental protection and enhanced leaching process was proposed to recover all elements from spent lithium iron phosphate(LiFePO_(4)) lithium batteries.In order to reduce the influence of Al impurity in th... A green environmental protection and enhanced leaching process was proposed to recover all elements from spent lithium iron phosphate(LiFePO_(4)) lithium batteries.In order to reduce the influence of Al impurity in the recovery process,NaOH was used to remove impurity.After impurity removal,the spent LiFePO_(4) cathode material was used as raw material under the H_(2)SO_(4) system,and the pressure oxidation leaching process was adopted to achieve the preferential leaching of lithium.The E-pH diagram of the Fe-P-Al-H_(2)O system can determine the stable region of each element in the recovery process of spent LiFePO_(4)Li-batteries.Under the optimal conditions(500 r·min^(-1),15 h,363.15 K,0.4 MPa,the liquid-solid ratio was 4:1 ml·g^(-1)and the acid-material ratio was 0.29),the leaching rate of Li was 99.24%,Fe,Al,and Ti were 0.10%,2.07%,and 0.03%,respectively.The Fe and P were precipitated and recovered as FePO_(4)·2H_(2)O.The kinetic analysis shows that the process of high-pressure acid leaching of spent LiFePO_(4) materials depends on the surface chemical reaction.Through the life cycle assessment(LCA)of the spent LiFePO_(4) whole recovery process,eight midpoint impact categories were selected to assess the impact of recovery process.The results can provide basic environmental information on production process for recycling industry. 展开更多
关键词 Spent lifePO_(4)Li-batteries Oxidative leaching Kinetic study life cycle assessment
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Cathode nanoarchitectonics with Na_(3)VFe_(0.5)Ti_(0.5)(PO_(4))_(3): Overcoming the energy barriers of multielectron reactions for sodium-ion batteries
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作者 Vaiyapuri Soundharrajan Sungjin Kim +7 位作者 Subramanian Nithiananth Muhammad H.Alfaruqi JunJi Piao Duong Tung Pham Vinod Mathew Sang A.Han Jung Ho Kim Jaekook Kim 《Carbon Energy》 SCIE EI CAS CSCD 2024年第9期1-14,共14页
High electrochemical stability and safety make Na+superionic conductor(NASICON)-class cathodes highly desirable for Na-ion batteries(SIBs).However,their practical capacity is limited,leading to low specific energy.Fur... High electrochemical stability and safety make Na+superionic conductor(NASICON)-class cathodes highly desirable for Na-ion batteries(SIBs).However,their practical capacity is limited,leading to low specific energy.Furthermore,the low electrical conductivity combined with a decline in capacity upon prolonged cycling(>1000 cycles)related to the loss of active material-carbon conducting contact regions contributes to moderate rate performance and cycling stability.The need for high specific energy cathodes that meet practical electrochemical requirements has prompted a search for new materials.Herein,we introduce a new carbon-coated Na_(3)VFe_(0.5)Ti_(0.5)(PO_(4))_(3)(NVFTP/C)material as a promising candidate in the NASICON family of cathodes for SIBs.With a high specific energy of∼457 Wh kg^(-1) and a high Na+insertion voltage of 3.0 V versus Na^(+)/Na,this cathode can undergo a reversible single-phase solid-solution and two-phase(de)sodiation evolution at 28 C(1 C=174.7 mAh g^(-1))for up to 10,000 cycles.This study highlights the potential of utilizing low-cost and highly efficient cathodes made from Earth-abundant and harmless materials(Fe and Ti)with enriched Na^(+)-storage properties in practical SIBs. 展开更多
关键词 Fe and Ti swapping Na_(3)VFe_(0.5)Ti_(0.5)(PO_(4))_(3) prolonged cycle life structural stabilit
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不同负极材料对LiFePO_(4)高功率储能器件循环性能的影响
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作者 张玉曼 范羚羚 杨重阳 《储能科学与技术》 CAS CSCD 北大核心 2024年第9期3245-3253,共9页
磷酸铁锂(LiFePO_(4),LFP)以低成本、高安全性、长循环寿命等优点在近些年来备受关注,然而市场上常见的LFP储能器件在0.1~2 C倍率的循环寿命为2000次左右。为了进一步开发高功率、长寿命的LFP储能器件,本文设计了容量为9 Ah的不同负极材... 磷酸铁锂(LiFePO_(4),LFP)以低成本、高安全性、长循环寿命等优点在近些年来备受关注,然而市场上常见的LFP储能器件在0.1~2 C倍率的循环寿命为2000次左右。为了进一步开发高功率、长寿命的LFP储能器件,本文设计了容量为9 Ah的不同负极材料(硬碳/软碳/石墨)软包储能器件。对4 C大倍率循环性能进行探究,发现4000次循环后,硬碳和软碳用作负极的储能器件的容量保持率分别为83.0%、78.9%,优于石墨(51.6%)。通过XRD、EIS、容量增量法和电压微分法等手段进行分析,发现接触内阻和SEI膜内阻增加,以及结构变化造成负极中锂离子的消耗是容量衰减的主要原因。进一步探究石墨用作负极时循环寿命差的原因,发现石墨用作负极时库仑效率较低,工作温度较高,dQ/dV峰值在循环过程中发生更大的位移,峰强的降幅也较大。由于石墨的层间距为0.335 nm,小于软碳(0.360 nm)和硬碳(0.395 nm),在反复脱嵌锂过程中石墨更易发生结构变化,造成体积膨胀,因此循环后接触电阻和SEI膜电阻增长幅度较高,锂离子扩散动力学也更差。与石墨相比,硬碳和软碳用作大倍率LFP储能器件的负极活性物质时具有更长的循环寿命。 展开更多
关键词 磷酸铁锂 硬碳 软碳 石墨 循环寿命
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泄浊通络方治疗慢性肾脏病3-4期临床研究
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作者 苏保林 李敬 +1 位作者 黎志彬 汤水福 《新中医》 CAS 2024年第11期69-73,共5页
目的:观察泄浊通络方治疗慢性肾脏病3-4期的疗效及对患者生活质量的影响。方法:选取100例慢性肾脏病3-4期患者,按随机数字表法分为试验组及对照组各50例。2组均给予基础治疗,试验组给予泄浊通络方,对照组给予安慰剂,2组疗程均为12周。比... 目的:观察泄浊通络方治疗慢性肾脏病3-4期的疗效及对患者生活质量的影响。方法:选取100例慢性肾脏病3-4期患者,按随机数字表法分为试验组及对照组各50例。2组均给予基础治疗,试验组给予泄浊通络方,对照组给予安慰剂,2组疗程均为12周。比较2组临床疗效及中医证候疗效,比较2组治疗前后实验室相关指标值[丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、血清钾(K+)、血肌酐(SCr)、血清胱抑素C(CysC)、尿素氮(BUN)、尿微量白蛋白/尿肌酐(ACR)、尿蛋白定量、估算肾小球过滤率(eGFR)]、生活质量评分[生理健康(PCS)、心理健康(MCS)、肾病负担(KDB)、肾病影响(KDE)、症状影响(DRS)]的变化。结果:试验组临床疗效总有效率为80.0%,对照组为60.9%,2组比较,差异有统计学意义(P<0.05)。试验组中医证候疗效总有效率为88.9%,对照组为78.3%,2组比较,差异有统计学意义(P<0.05)。治疗后,2组BUN、SCr、CysC、ACR、尿蛋白定量指标值均较治疗前下降(P<0.05),试验组BUN、SCr、CysC、ACR、尿蛋白定量指标值均低于对照组(P<0.05)。治疗后,2组eGFR指标值均较治疗前升高(P<0.05),试验组eGFR指标值高于对照组(P<0.05)。治疗后,试验组PCS、MCS、KDB、KDE、DRS评分均较治疗前升高(P<0.05),且上述5项评分均高于对照组(P<0.05)。结论:泄浊通络方治疗慢性肾脏病3-4期效果较好,可改善肾功能,提高生活质量。 展开更多
关键词 慢性肾脏病 3-4 泄浊通络方 生活质量
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Sulfur vacancies-induced“Electron Bridge”in Ni_(4)Mo/Sv-Zn_(x)Cd_(1-x)S regulates electron transfer for efficient H_(2)-releasing photocatalysis 被引量:1
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作者 Xin Zhang Manyi Gao +3 位作者 Longyu Qiu Jie Sheng Weiwei Yang Yongsheng Yu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第4期64-71,共8页
Despite the existence of plentiful photocatalyst heterojunctions,their separation efficiency and charge flow precision remain low on account of lacking interfacial modulation.Herein,through a defect-induced heterojunc... Despite the existence of plentiful photocatalyst heterojunctions,their separation efficiency and charge flow precision remain low on account of lacking interfacial modulation.Herein,through a defect-induced heterojunction constructing strategy,Ni4Mo alloys were in-situ grown on the unsaturated coordinated sulfur atoms of sulfur vacancies-rich ZCS(Sv-ZCS)via interfacial Ni-S covalent bonds.The experimental and theoretical results reveal that these unsaturated sulfur atoms induced by sulfur vacancies vastly facilitate to anchor more Ni-Mo nanoparticles and form abundant Ni-S covalent bonds,meanwhile,these sulfur vacancies could form dual internal electric field(IEF)and work with Ni-S covalent bonds as“Electron Bridge”to further accelerate photoelectrons transfer,as well as promote the activation of water molecules and the desorption of hydrogen proton.Accordingly,the optimized Ni_(4)Mo/Sv-ZCS composite achieves an improved photocatalytic hydrogen evolution(PHE)rate of 94.69 mmol h^(-1)g^(-1)without an evident decrease after 6 cycles of photocatalytic tests,which is 21.2 and 1.94 times higher than those of Pt/ZCS and Ni_(4)Mo/ZCS,respectively.This tactic opens a new way for optimizing Zn_(x)Cd_(1-x)S-based heterojunctions by constructing sulfur vacancies and covalent bonds as“Electron Bridge”to enhance the activity of PHE. 展开更多
关键词 Ni_(4)Mo Sulfur vacancies-rich Zn_(x)Cd_(1-x)S Electron bridge Photocatalytic hydrogen evolution
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Variable valence Mo^(5+)/Mo^(6+)ionic bridge in hollow spherical g-C_(3)N_(4)/Bi_(2)MoO_(6) catalysts for promoting selective visible light-driven CO_(2)photoreduction into CO 被引量:2
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作者 Wenjie He Yuechang Wei +8 位作者 Jing Xiong Zhiling Tang Yingli Wang Xiong Wang Hui Xu Xiao Zhang Xiaolin Yu Zhen Zhao Jian Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期361-372,I0009,共13页
Herein,the catalysts of ultrathin g-C_(3)N_(4)surface-modified hollow spherical Bi2MoO6(g-C_(3)N_(4)/Bi2MoO6,abbreviated as CN/BMO)were fabricated by the co-solvothermal method.The variable valence Mo^(5+)/Mo^(6+)ioni... Herein,the catalysts of ultrathin g-C_(3)N_(4)surface-modified hollow spherical Bi2MoO6(g-C_(3)N_(4)/Bi2MoO6,abbreviated as CN/BMO)were fabricated by the co-solvothermal method.The variable valence Mo^(5+)/Mo^(6+)ionic bridge in CN/BMO catalysts can boost the rapid transfer of photogenerated electrons from Bi2MoO6to g-C_(3)N_(4).And the synergy effect of g-C_(3)N_(4)and Bi2MoO6components remarkably enhance CO_(2)adsorption capability.CN/BMO-2 catalyst has the best performances for visible light-driven CO_(2)reduction compared with single Bi2MoO6and g-C_(3)N_(4),i.e.,its amount and selectivity of CO product are 139.50μmol g-1and 96.88%for 9 h,respectively.Based on the results of characterizations and density functional theory calculation,the photocatalytic mechanism for CO_(2)reduction is proposed.The high-efficient separation efficiency of photogenerated electron-hole pairs,induced by variable valence Mo^(5+)/Mo^(6+)ionic bridge,can boost the rate-limiting steps(COOH*-to-CO*and CO*desorption)of selective visible light-driven CO_(2)conversion into CO.It inspires the establishment of efficient photocatalysts for CO_(2)conversion. 展开更多
关键词 g-C_(3)N_(4) Bi_(2)MoO_(6) Mo^(5+)/Mo^(6+)ionic bridge CO_(2)photoconversion CO production
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Zr-doping stabilizes spinel LiMn_(2)O_(4)as a low cost long cycle life cathode for lithium ion batteries
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作者 张祥功 吴伟 +5 位作者 周思思 黄飞 许诗浩 尹良 杨伟 李泓 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期554-559,共6页
The present commercial spinel LiMn_(2)O_(4) delivers only 90 m Ah/g–115 m Ah/g,far lower than the theoretical specific capacity.It degrades fast caused by the Jahn–Teller effect,Mn dissolution and related side react... The present commercial spinel LiMn_(2)O_(4) delivers only 90 m Ah/g–115 m Ah/g,far lower than the theoretical specific capacity.It degrades fast caused by the Jahn–Teller effect,Mn dissolution and related side reactions that consume Li inventory.In this work,Zr doping is employed to improve the structural stability and electrochemical performance of spinel LiMn_(2)O_(4).Li_(1.06)Mn_(1.94-x)Zr_xO_4(x=0,0.01,0.02,0.04)have been successfully synthesized by a simple solid-state reaction method and evaluated as cathode for lithium ion batteries(LIB).Li_(1.06)Mn_(1.92)Zr_(0.02)O_4 is superior cathode material with a high capacity of 122 m Ah/g at 1-C rate;long cycle stability,98.39%retention after 100 cycles at 1-C rate,excellent high rate performance 107.1 m Ah/g at 10-C rate,and high temperature performance 97.39%retention after 60 cycles.These are thought to be related to Zr doping effectively stabilizing the spinel LiMn_(2)O_(4),by forming stronger Zr–O bonds in the octahedron,suppressing the Jahn–Teller effect,thus improving electrochemical performance. 展开更多
关键词 lithium battery CATHODE LiMn_(2)O_(4) cycle life
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Simulation of the Construction of a Swivel Bridge Using BIM 4D
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作者 Moussa Traore Guanhua Zhao Xiaoyong Zhou 《Open Journal of Civil Engineering》 CAS 2023年第1期139-154,共16页
The AEC (Architecture, Engineering, and Construction) industry is gradually shifting away from 2D CAD drawings and toward Building Information Modeling as a result of the fast development of science and technology (BI... The AEC (Architecture, Engineering, and Construction) industry is gradually shifting away from 2D CAD drawings and toward Building Information Modeling as a result of the fast development of science and technology (BIM). The BIM idea’s introduction emphasizes the need to specify a building in a single building model with adequate information to suit its different needs rather than defining it in fragmented documents. This research work aims to use the BIM 4D for the simulation of the construction sequence of a Swivel Bridge. For that, the software Revit was used to make the 3D model of the bridge, and the software Navisworks was used for the 4D construction simulation of the project. The results demonstrated that BIM technology could help reduce delays and problems with the schedule and improve communication among stakeholders, and BIM visualization and simulation features were very useful compared to traditional planning methods. 展开更多
关键词 BIM 4D Swivel bridge 4D Simulation 3D Model
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Crystalline and amorphous metal sulfide composite electrode materials with long cycle life:Preparation and performance of hybrid capacitors
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作者 DING Ning WANG Siyu +4 位作者 YU Shihua XU Pengcheng HAN Dandan SHI Dexin ZHANG Chao 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第9期1784-1794,共11页
Crystalline@amorphous NiCo_(2)S_(4)@MoS_(2)(v-NCS@MS)nanostructures were designed and constructed via an ethylene glycol-induced strategy with hydrothermal synthesis and solvothermal method,which simultaneously realiz... Crystalline@amorphous NiCo_(2)S_(4)@MoS_(2)(v-NCS@MS)nanostructures were designed and constructed via an ethylene glycol-induced strategy with hydrothermal synthesis and solvothermal method,which simultaneously realized the defect regulation of crystal NiCo_(2)S_(4) in the core.Taking advantage of the flexible protection of an amor-phous shell and the high capacity of a conductive core with defects,the v-NCS@MS electrode exhibited high specif-ic capacity(1034 mAh·g^(-1) at 1 A·g^(-1))and outstanding rate capability.Moreover,a hybrid supercapacitor was assembled with v-NCS@MS as cathode and activated carbon(AC)as anode,which can achieve remarkably high specific energy of 111 Wh·kg^(-1) at a specific power of 219 W·kg^(-1) and outstanding capacity retention of 80.5%after 15000 cycling at different current densities. 展开更多
关键词 crystalline@amorphous heterostructure NiCo2S4@MoS2 hybrid supercapacitor defect design long cycle life
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Molecular Design of Crown Ethers. 19~1. Synthesis of Novel Disulfide and Diselenide-Bridged Bis (benzo-12-crown-4)s and their Ag^+ Selective Electrode Properties 被引量:1
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作者 Heng Yi ZHANG Yu LIU (Department of Chemistry, Nankai University, Tianjin 300071) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第2期115-118,共4页
Two novel heteroatom-bridged his (benzo-12-crown-4 ether)s, i.e. his [2-nitro-4,5 (1,4,7,10-tetraoxadecamethylene) disulfide 1 and diselenide 2, have been synthesized. X ray crystallographic structure was obtained for... Two novel heteroatom-bridged his (benzo-12-crown-4 ether)s, i.e. his [2-nitro-4,5 (1,4,7,10-tetraoxadecamethylene) disulfide 1 and diselenide 2, have been synthesized. X ray crystallographic structure was obtained for 1. Ion selective electrodes (ISE) for Ag+, containing 1 and 2 in PVC membrane as neutral carriers, were prepared, and their selectivity coefficients for Ag^+ (K_(Ag.M)^(pot)) were determined against other heavy metal ions, alkali and alkaline-earth metal ions. and ammonium ion. These ISEs showed excellent Ag^+ selectivities, log K_(Ag.M)^(pot) ≤ -3.8, against most of the interfering canons examined, except for Hg^+. 展开更多
关键词 Heteroatom-bridged his (benzo-12-crown-4 ether)s ion selective electrodes selectivity coefficients.
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Zr-4合金疲劳裂纹扩展试验及仿真研究
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作者 董云桥 甘旭文 舒凌宏 《兵器材料科学与工程》 CAS CSCD 北大核心 2024年第5期18-24,共7页
为了准确获得Zr-4合金的疲劳裂纹扩展参数及剩余疲劳寿命,进行了3组紧凑拉伸试验(CT),用Paris公式表征裂纹扩展速率。基于Franc3d和Abaqus的联合仿真验证试验数据的有效性。在确保了扩展参数准确的基础上,探讨了裂纹融合间距对Zr-4合金... 为了准确获得Zr-4合金的疲劳裂纹扩展参数及剩余疲劳寿命,进行了3组紧凑拉伸试验(CT),用Paris公式表征裂纹扩展速率。基于Franc3d和Abaqus的联合仿真验证试验数据的有效性。在确保了扩展参数准确的基础上,探讨了裂纹融合间距对Zr-4合金包壳管剩余疲劳寿命的影响。结果表明:CT试验裂纹扩展路径与联合仿真获得的裂纹路径一致,且模拟结果和理论结果的最大偏差为6.7%,得到裂纹扩展参数C=1.376×10^(10)、m=2.3787;两裂纹半径相同时,间距变化对剩余疲劳寿命无影响,裂纹融合时中间部分的应力强度因子出现较大突变,且大于两侧的应力强度因子。 展开更多
关键词 ZR-4合金 疲劳裂纹扩展 联合仿真 剩余寿命预测 应力强度因子
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Motoyosi Sugita—A “Widely Unknown” Japanese Thermodynamicist Who Explored the 4th Law of Thermodynamics for Creation of the Theory of Life
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作者 Kazumoto Iguchi 《Open Journal of Biophysics》 2016年第4期125-232,共109页
The purpose of this paper is to introduce to you, the Western people, nowadays a “widely unknown” Japanese thermodynamicist by the name of Motoyosi Sugita and his study on the thermodynamics of transient phenomena a... The purpose of this paper is to introduce to you, the Western people, nowadays a “widely unknown” Japanese thermodynamicist by the name of Motoyosi Sugita and his study on the thermodynamics of transient phenomena and his theory of life. This is because although he was one of the top theoretical physicists in Japan before, during and after WWII and after WWII he promoted the establishment of the biophysical society of Japan as one of the founding members, he himself and his studies themselves have seemed to be totally forgotten nowadays in spite that his study was absolutely important for the study of life. Therefore, in this paper I would like to present what kind of person he was and what he studied in physics as a review on the physics work of Motoyosi Sugita for the first time. I will follow his past studies to introduce his ideas in theoretical physics as well as in biophysics as follows: He proposed the bright ideas such as the quasi-static change in the broad sense, the virtual heat, and the field of chemical potential etc. in order to establish his own theory of thermodynamics of transient phenomena, as the generalization of the Onsager-Prigogine’s theory of the irreversible processes. By the concept of the field of chemical potential that acquired the nonlinear transport, he was seemingly successful to exceed and go beyond the scope of Onsager and Prigogine. Once he established his thermodynamics, he explored the existence of the 4th law of thermodynamics for the foundation of theory of life. He applied it to broad categories of transient phenomena including life and life being such as the theory of metabolism. He regarded the 4th law of thermodynamics as the maximum principle in transient phenomena. He tried to prove it all life long. Since I have recently found that his maximum principle can be included in more general maximum principle, which was known as the Pontryagin’s maximum principle in the theory of optimal control, I would like to explain such theories produced by Motoyosi Sugita as detailed as possible. And also I have put short history of Motoyosi Sugita’s personal life in order for you to know him well. I hope that this article helps you to know this wonderful man and understand what he did in the past, which was totally forgotten in the world and even in Japan. 展开更多
关键词 Unknown Japanese Thermodynamicist Motoyosi Sugita Thermodynamics of Transient Phenomena Virtual Heat Broad Quasi-Static Change Chemical Potential Field of Chemical Potential Diffusion Phenomena Number of Partition Dissipation Function Onsager’s Theory of Irreversible Processes Prigogine’s Least Production of Entropy 4th Law of Thermodynamics Maximum Principle Pontryagin’s Maximum Principle Bellman’s Optimality Principle Theory of Metabolism Theory of life CYBERNETICS
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Ni^(2+)掺杂LiFePO_4正极材料的合成及性能 被引量:10
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作者 唐红辉 戴曦 +1 位作者 张传福 杨平 《粉末冶金材料科学与工程》 EI 2006年第4期244-248,共5页
以共沉淀法制备的Fe1-xNixC2O4.2H2O(x=0,0.05,0.10)为铁源,采用高温固相反应法合成锂离子电池正极材料LiFe1-xNixPO4(x=0,0.05,0.10)。应用热重-差热分析探讨材料合成机理、X射线衍射和扫描电镜表征材料的晶体结构和颗粒形貌,充放电仪... 以共沉淀法制备的Fe1-xNixC2O4.2H2O(x=0,0.05,0.10)为铁源,采用高温固相反应法合成锂离子电池正极材料LiFe1-xNixPO4(x=0,0.05,0.10)。应用热重-差热分析探讨材料合成机理、X射线衍射和扫描电镜表征材料的晶体结构和颗粒形貌,充放电仪测试材料的充放电性能。结果表明,所合成的材料结晶完整,为均一橄榄石型结构,仅含少量三价铁杂质;在室温下以0.1C充放电时,比容量较高,达到150 mAh/g左右,当充放电倍率提高到0.4C时,充放电比容量仍达120 mAh/g以上;且掺杂少量Ni2+后,正极材料氧化峰与还原峰电势差仅为0.079 V,明显低于纯相LiFePO4的0.101 V,有利于抑制材料充放电过程中的极化。 展开更多
关键词 正极材料 life1-xNixPO4 合成 结构 充放电性能
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钒改性锂离子电池正极材料LiFe_(0.5)Mn_(0.5)PO_4/C电化学性能(英文) 被引量:3
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作者 龚强 王红 +3 位作者 廖小珍 麻微 何雨石 马紫峰 《物理化学学报》 SCIE CAS CSCD 北大核心 2012年第1期100-104,共5页
采用高温固相反应,以NH4VO3为钒源合成了化学计量式为(1-x)LiFe0.5Mn0.5PO4-xLi3V2(PO4)3/C(x=0,0.1,0.2,0.25,1)的钒改性磷酸锰铁锂正极材料.电化学测试表明钒改性能明显提高磷酸锰铁锂材料的充放电性能,其中x=0.2时得到的0.8LiFe0.5Mn... 采用高温固相反应,以NH4VO3为钒源合成了化学计量式为(1-x)LiFe0.5Mn0.5PO4-xLi3V2(PO4)3/C(x=0,0.1,0.2,0.25,1)的钒改性磷酸锰铁锂正极材料.电化学测试表明钒改性能明显提高磷酸锰铁锂材料的充放电性能,其中x=0.2时得到的0.8LiFe0.5Mn0.5PO4-0.2Li3V2(PO4)3/C(标记为LFMP-LVP/C)材料电化学性能最好,其0.1C倍率时的放电比容量为141mAh·g-1.X射线衍射(XRD)分析指出LFMP-LVP/C材料的微观结构为橄榄石型LiFe0.5Mn0.5PO4/C和NASICON型Li3V2(PO4)3组成的双相结构.能量色射X射线谱(EDS)分析结果指出,Fe、Mn、V、P元素在所合成材料中的分布非常均匀,表明所制备材料成分的均一性.Li3V2(PO4)3改性使材料的电导率明显提高.LiFe0.5Mn0.5PO4的电导率为1.9×10-8S·cm-1,而LFMP-LVP材料电导率提高到2.7×10-7S·cm-1.与纯Li3V2(PO4)3的电导率(2.3×10-7S·cm-1)相近.电化学测试表明钒改性使LFMP-LVP/C材料充放电过程电极极化明显减小,从而电化学性能得到显著提高.本文工作表明Li3V2(PO4)3改性可成为提高橄榄石型磷酸盐锂离子电池正极材料电化学性能的一种有效方法. 展开更多
关键词 锂离子电池 life0.5Mn0.5PO4 Li3V2(PO4)3改性 正极材料
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Cu^(2+)掺杂高密度LiFePO_4/C正极材料的合成及性能 被引量:2
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作者 常照荣 吕豪杰 +2 位作者 汤宏伟 付小宁 李华吉 《功能材料》 EI CAS CSCD 北大核心 2009年第10期1682-1684,共3页
以高密度FePO4作为前躯体,Cu(Ac)2为掺杂源,通过高温固相法合成了高振实密度的锂离子电池正极材料LiFe1-xCuxPO4/C(x=0、0.01、0.015、0.02、0.025)。采用X粉末衍射(XRD)、电子扫描显微镜(SEM)、循环伏安法(C-V)和恒电流充放电对合成的... 以高密度FePO4作为前躯体,Cu(Ac)2为掺杂源,通过高温固相法合成了高振实密度的锂离子电池正极材料LiFe1-xCuxPO4/C(x=0、0.01、0.015、0.02、0.025)。采用X粉末衍射(XRD)、电子扫描显微镜(SEM)、循环伏安法(C-V)和恒电流充放电对合成的材料掺杂进行了结构、形貌和电性能表征和分析研究。结果表明,所合成的掺杂复合材料LiFe1-xCuxPO4/C为典型的橄榄石型结构,结晶度高,具有较高的振实密度。掺杂Cu2+离子在很大程度上可以提高LiFePO4的电化学性能,当Cu含量为2.0%(质量分数)时,LiFe0.98Cu0.02PO4/C的振实密度可以达到1.98 g/cm3,比容量为最大值,0.1C倍率放电可达150.0mAh/g,体积比容量为297.0mAh/cm3;2C倍率放电比容量仍可以达到127.3mAh/g以上,体积比容量为252.1mAh/cm3。 展开更多
关键词 正极材料 锂离子电池 life1-xCuxPO4 离子掺杂 电化学性能
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澳大利亚Read4Life项目对我国儿童阅读推广的启示 被引量:17
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作者 权丽桃 《图书馆工作与研究》 CSSCI 北大核心 2015年第6期99-101,共3页
澳大利亚Read4Life项目是一项为0-5岁儿童建立阅读重要性感知的嵌入式活动,该项目通过阅读包与丰富的活动使图书馆在对儿童进行阅读推广过程中充当了重要的角色。我国儿童阅读推广应该借鉴该项目的成功之处,坚持儿童阅读推广的公益性,... 澳大利亚Read4Life项目是一项为0-5岁儿童建立阅读重要性感知的嵌入式活动,该项目通过阅读包与丰富的活动使图书馆在对儿童进行阅读推广过程中充当了重要的角色。我国儿童阅读推广应该借鉴该项目的成功之处,坚持儿童阅读推广的公益性,加强各组织机构间的合作,开设相关的培训课程,注重项目评估环节,关注国外相关研究成果。 展开更多
关键词 Read4life项目 图书馆 儿童阅读推广
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锂离子电池正极材料LiFe(MoO4)2的制备及其电化学性质 被引量:1
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作者 陈红 陈楠 +4 位作者 张培松 梁磊 洪源泽 杜菲 王春忠 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2015年第6期1312-1315,共4页
采用固相法合成纯相的LiFe(MoO4)2材料.利用X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和超导量子干涉仪(SQUID)对其晶体结构及其磁学性质进行研究,并采用恒流充放电测试研究该材料在3.0-1.0V内的电化学性质... 采用固相法合成纯相的LiFe(MoO4)2材料.利用X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和超导量子干涉仪(SQUID)对其晶体结构及其磁学性质进行研究,并采用恒流充放电测试研究该材料在3.0-1.0V内的电化学性质.电化学测试表明,LiFe(MoO4)2作为正极材料具有良好的循环性能,稳定比容量为200mA·h/g,充放电效率为98.5%. 展开更多
关键词 锂离子电池 life(MoO4)2 磁学性质 电化学性质
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碳包覆LiFe_(0.5)Co_(0.5)PO_4固溶体正极材料的制备及其电化学性能(英文) 被引量:1
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作者 钟艳君 吴振国 +3 位作者 田海 郭孝东 钟本和 王辛龙 《无机化学学报》 SCIE CAS CSCD 北大核心 2018年第8期1581-1589,共9页
分别以四水磷酸铁(Fe PO4·4H2O)和二水草酸亚铁(FeC_2O_4·2 H_2O)为铁源,采用简单便捷的流变相法制备了碳包覆LiFe_(0.5)Co_(0.5)PO_4固溶体材料(LiFe_(0.5)Co_(0.5)PO_4/C,简称为LFCP/C)。采用X射线衍射(XRD)、扫描电镜(SEM... 分别以四水磷酸铁(Fe PO4·4H2O)和二水草酸亚铁(FeC_2O_4·2 H_2O)为铁源,采用简单便捷的流变相法制备了碳包覆LiFe_(0.5)Co_(0.5)PO_4固溶体材料(LiFe_(0.5)Co_(0.5)PO_4/C,简称为LFCP/C)。采用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、恒流充放电等测试手段对复合材料的物相、形貌结构和电化学性能进行了表征和测试。结果表明,2种铁源得到的材料均为橄榄石晶型结构且结晶度良好,二者在颗粒尺寸分布、碳包覆效果和电化学性能方面具有显著的差别。用作锂离子电池正极材料时,以FeC_2O_4·2 H_2O为原料得到的LFCP/C具有更优异的电性能:在2.5~5.0 V电压范围内,0.1C倍率下(1C=150 m A·g^(-1)),放电比容量为137.5m Ah·g^(-1),在10C仍具有57.6 m Ah·g^(-1)的放电比容量;0.5C循环100次后容量仍保持78.1%。该样品更佳的电化学性能主要得益于其更小的平均颗粒尺寸,更高的比表面积和理想的碳包覆效果。 展开更多
关键词 锂离子电池 life0.5Co0.5PO4/C 流变相法 铁源 电化学性能
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LiFePO_(4)动力电池加速循环寿命实验研究 被引量:3
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作者 卢立丽 王庆华 +1 位作者 于冰 马洪斌 《电源技术》 CAS 北大核心 2021年第9期1112-1114,共3页
针对LiFePO_(4)动力电池循环寿命评估周期长,成本高的问题,设计了以充电倍率、放电倍率、环境测试温度以及多因素耦合为测试条件的加速循环容量衰退实验。实验表明,充、放电倍率加速寿命能力随着电池温度的升高而提高。在环境测试温度为... 针对LiFePO_(4)动力电池循环寿命评估周期长,成本高的问题,设计了以充电倍率、放电倍率、环境测试温度以及多因素耦合为测试条件的加速循环容量衰退实验。实验表明,充、放电倍率加速寿命能力随着电池温度的升高而提高。在环境测试温度为25~55℃时,温度升高具有明显的加速作用,进一步提高环境测试温度不再具有加速作用。该实验结果可为LiFePO_(4)动力电池多加速参数耦合的加速循环寿命高效评估研究提供参考,同时也可为动力电池延长使用寿命的设计提供参考。 展开更多
关键词 lifePO_(4) 动力电池 加速循环寿命
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LiFe_(1-y)Mg_yPO_4的制备及电化学性能研究 被引量:1
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作者 康晓雪 于雪飞 杨占旭 《辽宁石油化工大学学报》 CAS 2015年第5期5-9,共5页
采用机械活化一步固相法,在Fe位掺杂Mg2+合成了结晶度较好的LiFe1-yMgyPO4。采用XRD、SEM等方法对LiFe1-yMgyPO4的结构和形貌进行了表征,利用恒电流充放电法研究了Mg2+掺杂对LiFe1-yMgy PO4电化学性能的影响。结果表明,适量Mg2+掺杂不改... 采用机械活化一步固相法,在Fe位掺杂Mg2+合成了结晶度较好的LiFe1-yMgyPO4。采用XRD、SEM等方法对LiFe1-yMgyPO4的结构和形貌进行了表征,利用恒电流充放电法研究了Mg2+掺杂对LiFe1-yMgy PO4电化学性能的影响。结果表明,适量Mg2+掺杂不改变LiFePO4的晶体结构,同时可以细化颗粒粒径,增强导电性和可逆性,有效地提高LiFePO4的倍率性能和循环稳定性。LiFe0.99Mg0.01PO4在0.1C和1C倍率条件下首次放电比容量分别为158.7mAh/g和141.9mAh/g,循环50次后放电比容量几乎没有衰减。 展开更多
关键词 锂离子电池 lifePO4 life1-yMgyPO4 Mg2+掺杂 Fe位掺杂
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