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Cryptanalysis and improvement of a quantum secret sharing scheme based on χ-type entangled states 被引量:1
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作者 Zhu zhen-Chao Zhang Yu-Qing Fu An-Min 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第1期1-5,共5页
In the paper [2010 Chin. Phys. B 19 050306], Yang et al. put forward a novel three-party quantum secret sharing protocol of secure direct communication based on x-type entangled states, they claimed that the scheme is... In the paper [2010 Chin. Phys. B 19 050306], Yang et al. put forward a novel three-party quantum secret sharing protocol of secure direct communication based on x-type entangled states, they claimed that the scheme is secure. However, in this paper, we study the security of the protocol and find that it is insecure. Applying intercept and resend attack, the agent Bob can obtain Alice's secret without the help from the other agent Charlie. In the end, we give our effective modification for its improvement. 展开更多
关键词 quantum secret sharing quantum entanglement bell state nonorthogonal base
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Inference of General Mass Action-Based State Equations for Oscillatory Biochemical Reaction Systems Using <i>k</i>-Step Genetic Programming 被引量:1
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作者 Tatsuya Sekiguchi Hiroyuki Hamada Masahiro Okamoto 《Applied Mathematics》 2019年第8期627-645,共19页
Systems biology requires the development of algorithms that use omics data to infer interaction networks among biomolecules working within an organism. One major type of evolutionary algorithm, genetic programming (GP... Systems biology requires the development of algorithms that use omics data to infer interaction networks among biomolecules working within an organism. One major type of evolutionary algorithm, genetic programming (GP), is useful for its high heuristic ability as a search method for obtaining suitable solutions expressed as tree structures. However, because GP determines the values of parameters such as coefficients by random values, it is difficult to apply in the inference of state equations that describe oscillatory biochemical reaction systems with high nonlinearity. Accordingly, in this study, we propose a new GP procedure called “k-step GP” intended for inferring the state equations of oscillatory biochemical reaction systems. The k-step GP procedure consists of two algorithms: 1) Parameter optimization using the modified Powell method—after genetic operations such as crossover and mutation, the values of parameters such as coefficients are optimized by applying the modified Powell method with secondary convergence. 2) GP using divided learning data—to improve the inference efficiency, imposes perturbations through the addition of learning data at various intervals and adaptations to these changes result in state equations with higher fitness. We are confident that k-step GP is an algorithm that is particularly well suited to inferring state equations for oscillatory biochemical reaction systems and contributes to solving inverse problems in systems biology. 展开更多
关键词 SYSTEMS Biology Genetic Programming Inverse Problems OSCILLATORY BIOCHEMICAL Reaction SYSTEMS GMA-based state Equations
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STUDY OF NORTHERN WINTER ATMOSPHERIC ACTIVE CENTERS (AAC) CLIMATE BASE-STATE WITH ITS CLIMATE VARIABILITY AND EFFECTS
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作者 施能 陈辉 夏冬冬 《Journal of Tropical Meteorology》 SCIE 2000年第2期194-201,共8页
The study of low-frequency oscillations is an important part of climate variability research. In view of insufficient efforts spent on multidecadal and ENSO-scale changes of the climate, the present paper undertakes s... The study of low-frequency oscillations is an important part of climate variability research. In view of insufficient efforts spent on multidecadal and ENSO-scale changes of the climate, the present paper undertakes study of > 30 year slowly-varying means, called climate base state (CBS), of northern winter AAC’s in the past 100 years and more, with the CBS variability and its temporal evolution investigated, indicating that Aleutian low and Icelandic low (North Pacific high and North American high) experience maximum (minimum) variation in the CBS. The CBS exhibits two modes for its variation. The positive (negative) phase of mode I presents a weak (strong) NAO (North Atlantic Oscillation), a weaker (stronger) NPO (North Pacific Oscillation), a robust (feeble) Siberian high and a quite weak (vigorous) Aleutian low whilst the positive (negative) phase of mode II reveals a feeble (strong) Aleutian low and a weak (robust) Siberian high. Also, the research shows that the recent CBS of northern circulations is in a remarkably negative phase of mode I and a noticeably positive phase of mode II, viz., in the background of slowly-varying circulations of an exceptionally weak Siberian high, an extremely vigorous Aleutian low and an intense NAO. The background field is likely to persist for a matter of 30 years such that northern winter temperature is expected to be in such a warm situation for a long period to follow. 展开更多
关键词 ATMOSPHERIC active centers CLIMATE base-state CLIMATE variabilit
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Magnetic Field Measurement with Heisenberg Limit Based on Solid Spin NOON State
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作者 周雷鸣 董杨 孙方稳 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第6期164-168,共5页
The maximum entangled number state (NOON state) can improve the sensitivity of physical quantity measure- ment to the Heisenberg limit 1/N. In this work, the magnetic field measurement based on the individual solid ... The maximum entangled number state (NOON state) can improve the sensitivity of physical quantity measure- ment to the Heisenberg limit 1/N. In this work, the magnetic field measurement based on the individual solid spin NOON state is investigated. Based on the tunable effective coupling coefficient, we propose a generation scheme of the three-spin NOON state, i.e, the Creenberger-Horne-Zeilinger (CHZ) state, and discussed the mea- surement resolution reduction due to decoherence. It is unnecessary to entangle spins as many as possible when decoherence exists. In practice, defect spins in diamond and alp donors with long coherence time can be applied with current techniques in the nano-scaled high resolution magnetic measurement. 展开更多
关键词 Magnetic Field Measurement with Heisenberg Limit based on Solid Spin NOON state
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The singularity in the state-based peridynamic solution of uniaxial tension
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作者 Zaixing Huang 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2018年第5期351-354,363,共5页
We solve the local uniaxial tension of an infinite rod in the framework of non-ordinary state-based peridynamics.The singular solutions of stress and displacement are acquired.When the influencing range of the window ... We solve the local uniaxial tension of an infinite rod in the framework of non-ordinary state-based peridynamics.The singular solutions of stress and displacement are acquired.When the influencing range of the window function approaches zero,these two solutions will return to the solutions of the classical elasticity.The analysis shows that the singularities of the solutions stem from such a feature of the window function that must be represented by a rapidly decreasing function in physics.Contrary to the classical elasticity,the stress solution of peridynamics is smoother than the displacement solution.In addition,a criterion used to select the window function is proposed in this paper. 展开更多
关键词 Peridynmics Non-ordinary state-based PERIDYNAMICS SINGULARITY LOCAL UNIAXIAL tension ANALYTICAL SOLUTION
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Analyzing and Designing Business Processes Management System Based on Transformation of Instantiated Ontology’s State
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作者 YAO Qing WANG Haiyang 《Wuhan University Journal of Natural Sciences》 CAS 2006年第5期1126-1131,共6页
The paper discusses efforts of finding a simple and transparent method to analyze business processes and developing its management system architecture. By introducing ontology and its state, the approach tried to find... The paper discusses efforts of finding a simple and transparent method to analyze business processes and developing its management system architecture. By introducing ontology and its state, the approach tried to find a unified representation and a flexible choreography of business processes. The main idea of the paper is the transformation of ontology's states, which are the most important scenarios of enterprises. The business activity composition, that is, case composition based on an AI technique, Case Based Reason (CBR), which is to solve new problems by retrieving solutions to previous problems, and then store the modified solution. The main interest in CBR relies on that it allows a system to avoid past failures and exploit past successes. 展开更多
关键词 ontology business process management (BPM) case based reason(CBR) state transform
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Low Spin State Dinuclear Fe^Ⅲ,Ni^Ⅱand Cu^ⅡComplexes Supported by 1-Amino-2-indanol Schiff Base Derivatives
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作者 崔燕峰 许亚蒙 +5 位作者 孙昊 杨华 张瑾 李亚红 刘玮 董亚萍 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第8期1293-1304,共12页
Four complexes of compositions [Fe2(L^1)2](1), [Ni2(L^1)2](2), [Ni2(L^2)2](3) and [Cu2(L^2)2](4)(H2L^1 = 1-(((2-hydroxy-2,3-dihydro-1 H-inden-1-yl)imino)methyl)naphthalen-2-ol, H2L^2 = 4-((2-h... Four complexes of compositions [Fe2(L^1)2](1), [Ni2(L^1)2](2), [Ni2(L^2)2](3) and [Cu2(L^2)2](4)(H2L^1 = 1-(((2-hydroxy-2,3-dihydro-1 H-inden-1-yl)imino)methyl)naphthalen-2-ol, H2L^2 = 4-((2-hydroxy-2,3-dihydro-1 H-inden-1-yl)imino)pentan-2-one) were synthesized under solvothermal conditions. The structures of 1~4 were characterized by X-ray single-crystal diffraction analysis. The magnetic properties of these four complexes are investigated. The dc magnetic measurements indicate that the metal ions of 1, 2 and 3 are in the low spin state, revealing the strong ligand field character of 1-amino-2-indanol. This work provides an effective approach to coordination complexes possessing low spin state metal centers. 展开更多
关键词 transition metal low spin state Schiff base magnetic property
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Transient state model of actin-based motility
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作者 Li-miao Bai and Yuan Lin~(a)) Department of Mechanical Engineering,The University of Hong Kong,Hong Kong SAR,China 《Theoretical & Applied Mechanics Letters》 CAS 2011年第1期73-76,共4页
We developed a transient model for actin-based motility.Diffusion of actin monomers was included in the formulation and its influence on the speed of actin-driven cargos was examined in detail.Our results clearly demo... We developed a transient model for actin-based motility.Diffusion of actin monomers was included in the formulation and its influence on the speed of actin-driven cargos was examined in detail.Our results clearly demonstrated how actin polymerization accelerates cargos that are initially stationary,as well as how steady-state is eventually reached.We also found that,due to polymerization and diffusion,actin monomer concentration near the load surface can be significantly lower than that in the rest of the comet tail,suggesting that many previous models may not be very accurate. 展开更多
关键词 actin-based motility POLYMERIZATION DIFFUSION transient state
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The Rising,Recession and Revitalization of the Traditional Industrial Base in the Northeastern United States 被引量:1
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作者 姚丽丽 《海外英语》 2012年第23期211-214,共4页
The distribution of American industries has been unbalanced and most of the early industrial regions were centered in northeastern America.The northeastern traditional industrial base once was called"manufacturin... The distribution of American industries has been unbalanced and most of the early industrial regions were centered in northeastern America.The northeastern traditional industrial base once was called"manufacturing belt".Since the 1950s,old industrial bases in the United States have been under recession.The northeastern region was then even called"rust belt".Some issues and measures of policy were set up by the government to adjust and restructure the old industrial bases,and some are useful experience and inspirations for our country,such as setting up special branches and organizations,establishing and implementing strategic planning for the adjustment and restructure of old industrial bases,adjusting the industrial branch and system,emphasizing on environment control and preservation and so on was achieved.Learning the successful experience from America,effective countermeasures and steps must be taken to accelerate the revival of the old industrial base in Northeastern China. 展开更多
关键词 NORTHEASTERN UNITED states traditional industrial
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Optimal Stiffness for Flexible Connectors on A Mobile Offshore Base at Rough Sea States 被引量:1
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作者 WU Lin-jian WANG Yuan-zhan +4 位作者 WANG Yu-chi CHEN Jia-yu LI Yi LI Qing-mei XIE Tao 《China Ocean Engineering》 SCIE EI CSCD 2018年第6期683-695,共13页
This paper investigates a simplified method to determine the optimal stiffness of flexible connectors on a mobile offshore base(MOB) during the preliminary design stage. A three-module numerical model of an MOB was us... This paper investigates a simplified method to determine the optimal stiffness of flexible connectors on a mobile offshore base(MOB) during the preliminary design stage. A three-module numerical model of an MOB was used as a case study. Numerous constraint forces and relative displacements for the connectors at rough sea states with different wave angles were utilized to determine the optimized stiffness of the flexible connectors. The range of optimal stiffnesses for the connectors was obtained based on the combination and intersection of the optimized stiffness results, and the implementation steps were elaborated in detail. The percentage reductions of the optimized and optimal stiffness of the flexible connector were determined to quantitatively evaluate the decreases of the constraint force and relative displacement of the connectors compared with those calculated by using the original range of the connector stiffnesses. The results indicate the accuracy and feasibility of this method for determining the optimal stiffness of the flexible connectors and demonstrate the rationality and practicability of the optimal stiffness results. The research ideas, calculation process, and solutions for the optimal stiffness of the flexible connectors of an MOB in this paper can provide valuable technical support for the design of the connectors in similar semisubmersible floating structures. 展开更多
关键词 mobile offshore base(MOB) flexible connectors the optimal stiffness rough sea states
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Charge Transfer and Normal State Anomaly in Bi-Based High T_c Superconductors Studied by Positron Annihilation
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作者 Chen Feng Zheng Sheng-nan Zhang Su-qun Gou Zhen-hui Li An-li Zhu Sheng-yun (China Institute of Atomic Energy,P.O.Box 275,Beijing 102413)Liu Zhi-yi Zhao Zhong-xian (Institute of Physics,Chinese Academy of Sciences,Beijing 100080) 《Chinese journal of nuclear physics》 1994年第3期278-282,共5页
The positron annihilation lifetime and Doppler broadened line-shapeparameter have been measured between 77 and 300 K for Bi<sub>1.8</sub>Pb<sub>0.1</sub>Sb<sub>0.1</sub>Sr<sub>... The positron annihilation lifetime and Doppler broadened line-shapeparameter have been measured between 77 and 300 K for Bi<sub>1.8</sub>Pb<sub>0.1</sub>Sb<sub>0.1</sub>Sr<sub>2</sub>Ca<sub>2</sub>Cu<sub>3</sub>O<sub>x</sub>,Bi<sub>1.8</sub>Sb<sub>0.2</sub>Sr<sub>2</sub>Ca<sub>2</sub>Cu<sub>3</sub>O<sub>x</sub> and Bi<sub>1.7</sub>Pb<sub>0.2</sub>Sb<sub>0.1</sub>Sr<sub>2</sub>Ca<sub>2</sub>Cu<sub>2</sub>O<sub>x</sub>. The charge transfer from Cu-Olayers to Bi-O layers has been observed across T<sub>c</sub>s for all samples.Three samples allshow two normal state anomalies around 160 K and 240 K,respectively.The anomalyaround 160 K is attributed to the structural instability and that around 240 Kpresumably to the displacement phase transition. 展开更多
关键词 Bi-based SUPERCONDUCTORS Charge transfer Normal state ANOMALY Positron annihilation
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Research on evaluation model of technology innovation ability of state-owned enterprises in northeast industry base
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作者 CHEN Hongguang QI Guoyou ZHANG Ning 《Journal of Northeast Agricultural University(English Edition)》 CAS 2007年第2期184-187,共4页
The paper viewed the current problem that state-owned enterprises in northeast industry base hadn't technologies of their own intellectual property right, whose sources mainly depended on imitation and introduction f... The paper viewed the current problem that state-owned enterprises in northeast industry base hadn't technologies of their own intellectual property right, whose sources mainly depended on imitation and introduction from abroad. Operational evaluation method and index criteria system of enterprises technology innovation ability were put forward in this paper, different enterprises may revise the model according to their actual situations to evaluate the enterprise technological innovation ability scientifically and quickly. The findings will be helpful to correlative departments to formulate the related policies and also has important theoretical and practical value in technological innovation project of enterprise. 展开更多
关键词 state-owned enterprises in northeast industry base technology innovation ability appraised criteria system
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不同应力状态下定向凝固镍基高温合金的组织演变规律
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作者 袁嘉耀 曹铁山 +3 位作者 王威 迟庆新 赵杰 程从前 《金属热处理》 北大核心 2026年第3期70-76,共7页
为研究相同温度和时间、不同应力状态下定向凝固镍基高温合金DZ411的组织演变规律,设计了多级截面圆柱试样。利用光学显微镜和扫描电镜对950℃×150 h蠕变试验后的合金组织进行观察,并对γ'强化相的尺寸和形貌进行定量分析。结... 为研究相同温度和时间、不同应力状态下定向凝固镍基高温合金DZ411的组织演变规律,设计了多级截面圆柱试样。利用光学显微镜和扫描电镜对950℃×150 h蠕变试验后的合金组织进行观察,并对γ'强化相的尺寸和形貌进行定量分析。结果表明,所设计的多级截面试样可实现在相同温度和时间条件下获得不同应力均匀分布状态的试样。蠕变试验后,无应力时,DZ411合金的γ'相的形貌呈带圆角立方块状形貌,γ'相的等效直径为0.25μm。随着应力的增加,γ'相的尺寸逐渐增加,立方度降低并向椭球形转变,同时γ'相连结聚集出现筏化现象,且筏化程度随应力的增加而增大。在200 MPa下,γ'相的等效直径为0.45μm,筏化系数增大至1.92。 展开更多
关键词 镍基高温合金 应力状态 γ'相粒子 定量表征
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基于健康信念模式的综合护理对主动脉夹层术后患者自我管理水平与生活质量的影响
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作者 孔颖 范宝梅 《临床医学研究与实践》 2026年第7期162-165,共4页
目的探讨基于健康信念模式的综合护理在主动脉夹层术后患者中的应用效果。方法选择2023年8月至2025年2月医院收治的82例主动脉夹层患者,以随机数字表法将其分为对照组和观察组,每组41例。对照组采取常规术后护理,观察组在常规护理基础... 目的探讨基于健康信念模式的综合护理在主动脉夹层术后患者中的应用效果。方法选择2023年8月至2025年2月医院收治的82例主动脉夹层患者,以随机数字表法将其分为对照组和观察组,每组41例。对照组采取常规术后护理,观察组在常规护理基础上实施基于健康信念模式的综合护理。比较两组的护理效果。结果观察组的疾病知识掌握程度优于对照组(P<0.05)。护理后,观察组的焦虑自评量表(SAS)与抑郁自评量表(SDS)评分低于对照组,自我管理测评量表各维度评分及健康调查简表(SF-36)评分均高于对照组(P<0.05)。观察组的并发症总发生率低于对照组,满意度高于对照组(P<0.05)。结论基于健康信念模式的综合护理能提升主动脉夹层术后患者疾病知识掌握程度、自我管理能力、生活质量,缓解不良情绪,减少并发症。 展开更多
关键词 主动脉夹层 基于健康信念模式的综合护理 心理状态 自我管理 生活质量
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固相摩擦增材制造技术研究进展及其应用现状
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作者 刘海滨 张迎星 +1 位作者 谢瑞山 陈树君 《金属学报》 北大核心 2026年第1期100-116,共17页
金属增材制造技术凭借快速制备复杂轻量化结构的优势,在工业领域备受青睐。然而,熔融类金属增材制造技术易产生成分偏析、内部孔洞及热裂纹等缺陷,促使研究者开发新型替代技术。近年来,基于搅拌摩擦原理的固相摩擦增材制造技术应运而生... 金属增材制造技术凭借快速制备复杂轻量化结构的优势,在工业领域备受青睐。然而,熔融类金属增材制造技术易产生成分偏析、内部孔洞及热裂纹等缺陷,促使研究者开发新型替代技术。近年来,基于搅拌摩擦原理的固相摩擦增材制造技术应运而生。该技术结合了搅拌摩擦技术与增材制造理念,在加工过程中完全避免了材料熔化,兼具高沉积速率、无需保护气体等优势,在金属结构件制造领域展现出广阔的应用前景。本文系统梳理了固相摩擦增材制造技术的国内外研究进展,概述了其技术分类、工艺-组织-性能、技术优势、装备研发、样件制备及固相修复应用。最后,总结了当前面临的技术挑战,为推动该技术的产业化应用提供参考。 展开更多
关键词 固相摩擦增材制造技术 复杂构件 应用现状 固相修复
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现代医学背景下原发性肥胖症的中医认识及诊疗刍议
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作者 顾成娟 王涵 仝小林 《南京中医药大学学报》 北大核心 2026年第2期165-172,共8页
原发性肥胖症是医学界面临的重大难题,现有减重西药并不能满足全部类型肥胖症的治疗需求。中医药治疗原发性肥胖症具有丰富的理论经验和临床实践基础,开发潜力较大。本文在《黄帝内经》“脂人、膏人、肉人”肥胖三型认识的基础上拓展了... 原发性肥胖症是医学界面临的重大难题,现有减重西药并不能满足全部类型肥胖症的治疗需求。中医药治疗原发性肥胖症具有丰富的理论经验和临床实践基础,开发潜力较大。本文在《黄帝内经》“脂人、膏人、肉人”肥胖三型认识的基础上拓展了“小膏人”和“脂膏人”的分型,构建肥胖五型新分类体系,突破了现代医学以单一指标认识肥胖症的局限。并根据原发性肥胖症的异质性特点,从基于能量代谢特征的实壅、虚壅论治,实壅以厚朴三物汤为核心方,根据胃肠饥饿型、情绪饥饿型、脑饥饿型分类辨治;虚壅以六君子汤为核心方,根据低代谢型特点辨治。通过凝练核心病机,归纳核心方药,从而提高中医治疗的精准性,与现有减重西药形成优势互补,提高肥胖症临床疗效。 展开更多
关键词 原发性肥胖症 肥胖异质性 壅态 分类辨治 态靶 黄帝内经 肥胖五型
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SiO_(2)纳米纤维复合PEO基固态电解质制备及锂电池电化学性能
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作者 郭勤 汤文文 +4 位作者 毛犁 张景梅 陈自娇 李雪梅 后春静 《电源技术》 北大核心 2026年第1期65-73,共9页
采用涂覆法将柔性SiO_(2)纳米纤维膜与PEO/LiTFSI复合制备S-PEO/LiTFSI复合固态电解质。复合电解质的力学与热学性能显著提升,其拉伸强度为1.50 MPa,断裂伸长率为21%,高于对照组(PEO/LiTFSI)的1.02 MPa和18%,熔融温度升高至55.1℃,而对... 采用涂覆法将柔性SiO_(2)纳米纤维膜与PEO/LiTFSI复合制备S-PEO/LiTFSI复合固态电解质。复合电解质的力学与热学性能显著提升,其拉伸强度为1.50 MPa,断裂伸长率为21%,高于对照组(PEO/LiTFSI)的1.02 MPa和18%,熔融温度升高至55.1℃,而对照组为50.5℃。复合电解质在30℃下离子电导率达1.3×10^(-4)S/cm,较对照组提升一个数量级;活化能为0.712 eV,显著低于对照组的0.952 eV。基于该电解质的Li||S-PEO/LiTFSI||Li对称电池在60℃经1100次循环后,电压滞后稳定于(24.8±0.2)mV;LiFePO_(4)||S-PEO/LiTFSI||Li电池在0.1 C/0.2 C下过电位为44/59 mV,远低于对照组的99/141 mV,0.8 C/1 C放电比容量达127/100 mAh/g。复合电解质锂离子电池的性能提升可归因于SiO_(2)三维网络提供的额外离子路径、机械增强及界面稳定性优化。 展开更多
关键词 聚合物基固态电解质 二氧化硅纳米纤维膜 锂电池 电化学性能
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氮和硫基共价有机框架的全固态电解质设计及锂金属电池性能研究
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作者 梁伟荃 吴家怡 +3 位作者 吴昊 廖春烨 钱艳楠 李运勇 《材料研究与应用》 2026年第3期280-289,共10页
锂金属电池(LMBs)因其高理论比容量(3860 mAh·g^(-1))和低还原电位(-3.04 V vs.SHE),被认为是实现下一代高性能储能设备的候选者。然而,由于锂金属负极具有枝晶隐患,且传统液态电解质存在化学稳定性差、易燃等安全问题,严重影响了... 锂金属电池(LMBs)因其高理论比容量(3860 mAh·g^(-1))和低还原电位(-3.04 V vs.SHE),被认为是实现下一代高性能储能设备的候选者。然而,由于锂金属负极具有枝晶隐患,且传统液态电解质存在化学稳定性差、易燃等安全问题,严重影响了电池的寿命和安全,阻碍了其商业化进程。为解决上述问题,采用简单的室温合成方法成功制备了富含活性位点的共价有机框架(COF-SH),通过溶液浇铸工艺将聚氧化乙烯(PEO)和COF-SH结合制备PEO@COF-SH聚合物固态电解质薄膜并将其应用于锂金属电池的电解质材料中。研究结果表明,COF-SH中丰富的活性位点可以调控COF结构的局部电化学环境,有效促进双三氟甲磺酰亚胺锂(LiTFSI)的解离,并加快Li^(+)在COF-SH有序的一维孔道结构中运输,从而促进了体系的动力学反应。强吸电子基可以调节共价有机骨架的电子结构,构建特定的阳离子导向通道。在这种高选择性的Li^(+)运输通道和调节的表面电荷下,实现了Li^(+)的均匀沉积和Li枝晶的抑制,提高阳极和电解质界面的稳定性。有序的纳米通道、丰富的活性位点可以促使离子的快速迁移,显著提升离子电导率,从而实现稳定的锂沉积和剥离。因此COF-SH电解质薄膜在60℃表现出0.81的高锂离子迁移数和4.0×10^(-4) S·cm^(-1)的离子电导率。Li/PEO@COF-SH/Li对称电池在0.1 mA·cm^(-2)的电流密度和0.1 mAh·cm^(-2)的面容量下稳定循环1500 h并保持16 mV的过电位,在0.2 mA·cm^(-2)的电流密度和0.2 mAh·cm^(-2)的面容量下稳定循环1000 h,过电位为34 mV。LiFePO_(4)/PEO@COF-SH/Li在1 C倍率下表现出154.3 mAh·g^(-1)的初始比容量,经过300次循环后依然有137.0 mAh·g^(-1)的可逆比容量,容量保持率为88.7%,循环容量衰减率每次循环仅为0.04%,表现出优异的循环稳定性。研究成果为设计柔性高离子电导率的PEO基固态电解质薄膜提供了重要的理论指导与实践参考。 展开更多
关键词 锂金属电池 锂枝晶 PEO基固态电解质 共价有机框架 亲锂位点 强吸电子基 溶液浇铸 均匀锂沉积
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挤压态镍基粉末高温合金FGH4113A热变形行为及组织演变规律
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作者 杨金龙 尹超 +2 位作者 熊江英 郭建政 冯干江 《稀有金属材料与工程》 北大核心 2026年第4期1045-1057,共13页
为探明挤压态新型镍基粉末高温合金FGH4113A热加工性能和调控变形组织,利用Gleeble热模拟试验机、金相显微镜、扫描电子显微镜、背散射电子衍射仪等研究了合金在温度1050~1150℃和应变速率0.001~0.1 s^(-1)范围内热变形行为和显微组织... 为探明挤压态新型镍基粉末高温合金FGH4113A热加工性能和调控变形组织,利用Gleeble热模拟试验机、金相显微镜、扫描电子显微镜、背散射电子衍射仪等研究了合金在温度1050~1150℃和应变速率0.001~0.1 s^(-1)范围内热变形行为和显微组织特征。结果表明:挤压态合金热变形前保温,1150℃时晶粒尺寸明显粗化。变形温度和应变速率对合金的变形流变应力和再结晶组织明显影响。推荐挤压态合金在γ+γ′双相区热变形,温度和应变速率区间为:1080~1100℃和0.001~0.01 s^(-1)。此区间内变形后,合金再结晶充分,晶粒内残余变形位错密度低,取向差接近,尺寸分布均匀,平均尺寸控制在5μm以内。可通过局部平均取向差、晶粒扩展取向差和反极图等多个维度分析再结晶晶粒和变形原始晶粒特征。 展开更多
关键词 FGH4113A 镍基高温合金 挤压态 热变形 组织演变
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镍基氧化物价态对尿素废水氧化反应电催化活性的影响
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作者 孙燕 焦鑫 +5 位作者 韩海荣 竹松博 徐敏 宁林钢 祁宇锋 任超 《福建农林大学学报(自然科学版)》 北大核心 2026年第1期142-150,共9页
【目的】探究不同价态镍基氧化物在尿素电催化氧化反应(UOR)中的催化性能,为优化镍基催化剂的价态调控机制提供理论依据。【方法】通过电沉积和热处理方法合成了Ni、NiO和Ni_(2)O_(3)3种不同价态的镍基催化剂。利用多种表征和测试技术,... 【目的】探究不同价态镍基氧化物在尿素电催化氧化反应(UOR)中的催化性能,为优化镍基催化剂的价态调控机制提供理论依据。【方法】通过电沉积和热处理方法合成了Ni、NiO和Ni_(2)O_(3)3种不同价态的镍基催化剂。利用多种表征和测试技术,对其UOR行为进行分析。【结果】NiO在UOR中展现出最低的起始电位[1.29 V(vs RHE)]和最高的电流密度,具有优异的反应动力学。原位阻抗和开路电位测试结果进一步表明,NiO的优异性能源于其快速的氧化重构过程以及对尿素分子的高效吸附能力。【结论】NiO在UOR中具有较强的催化性能。 展开更多
关键词 尿素废水 电催化 镍基催化剂 价态调控 氢气
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