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High-rate performance and super long-cycle stability of Na_(3)V_(2)(PO_(4))_(3)cathode material coated by diatomic doped carbon

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Rare Metals 2023年第5期42卷 1570-1582页

作者： Jia Kang Ling Zhu Fei-yang Teng Si-Qi Wang Yong-Gang Huang yan-hong xiang Zhe Chen Xian-Wen Wu School of Physics and Electromechanical Engineering Jishou UniversityJishou416000China School of Chemistry and Chemical Engineering Jishou UniversityJishou416000China

Na_(3)V_(2)(PO_(4))_(3)is considered as one of the most promising cathodes for sodium ion batteries due to its excellent thermal stability,long cycle life and high energy ***,the inferior intrinsic electronic conductivity which brings about the poor rate capability and cycling performance hinders its commercial ***,the S-N co-doped carbon-coated Na_(3)V_(2)(PO_(4))_(3)(NVP@SNC)has been synthesized to resolve the *** prepared NVP@SNC forms a hierarchical structure assembled with nanosheets,which is in favor of the electrolyte infiltration and shortening the Na^(+)transmission *** lattice defects can be induced in carbon layer by the co-doped elements(S-N),which reduce the Na^(+)diffusion energy barriers and provide adequate Na^(+)migration channels,thus jointly boosting the Na^(+)diffusion ***,the NVP@SNC cathode shows a high reversible capacity with outstanding rate performance and super long-cycle *** discharged at 2.0C,it delivers the capacity near to the theoretical value with a capacity retention of 88.7%after *** if the current is as high as 50.0C,a high capacity of 58.6 mAh·g^(-1)has been released,and41.4 mAh·g^(-1)has been remained after the super long cycling of 4000 *** study is expected to supply a new thought of developing high-performance cathodes by diatomic doping for sodium ion battery.

关键词： Sodium ion battery(SIB) Cathode material Na_(3)V_(2)(PO_(4))_(3) Diatomic doping Carbon coating

Follicle-stimulating hormone as a predictor for sperm retrieval rate in patients with nonobstructive azoospermia, a systematic review and meta-analysis

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Asian Journal of Andrology 2015年第2期17卷 281-284,I0010页

作者： Qi yang yan-Ping Huang hong-xiang Wang Kai Hu Yi-Xin Wang Yi-Ran Huang Bin Chen Department of Urology Ren Ji Hospital School of Medicine Shanghai Jiao Tong University Shanghai institute of Andrology Shanghai 200127 China.

Noninvasive parameters for predicating sperm retrieval rate （SRR） are desirables. Follicle-stimulating hormone （FSH） has been an important predictor since the first years of testicular sperm extraction. Recent studies showed continuous interests in FSH, with both pros and cons. Thus, we conducted a meta-analysis to evaluate the diagnostic value of FSH as a predictor for patients with nonobstructive azoospermia （NOA） taking testicular sperm retrieval. Eligible diagnosis tests were identified from electronic databases （Cochrane Central Register of Controlled Trials, Medline, and EMBASE） without language restrictions. The database search, quality assessment, and data extraction were performed independently by two reviewers. The reference standard was the sperm retrieval result. Diagnostic value of FSH were explored by area under receiver operation characteristics （ROC） curve using Review Manager, version 5.1.0 （Cochrane Collaboration, Oxford, UK） and Meta-DiSc, version 1.4. Meta regression will be done if there is heterogeneity. Then, we find 11 tests including a total of 1350 patients met the inclusion criteria. Our pooled analysis showed that the area under ROC curve of FSH was 0.72 ~ 0.04. Meta regression analyses showed that region and average age have an influence on the diagnostic value. FSH showed more diagnostic value with patients in East Asia and with younger patients. We concluded that FSH had moderate value in independently predicating SRR in men with NOA （area under curve 〉0.7）. More detailed diagnosis tests should be anticipated in the future to confirm the diagnostic value of other noninvasive parameters.

关键词： follicule-stimulating hormone meta-analysis nonobstructive azoospermia testicular sperm retrieval

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圆台型自聚焦超声压电换能器研究

声学技术 2005年第2期24卷 125-128页

作者：闫向宏中国石油大学物理科学与技术学院山东东营257061

对圆台型自聚焦超声压电换能器辐射声场分布进行了数值计算,分析了圆台换能器几何参数小端半径b、大端半径a以及高度h对轴向声场以及焦平面声场分布的影响。结果表明:圆台型自聚焦超声换能器轴向声场为振荡分布,声强平均值较高,存在一... 详细信息

对圆台型自聚焦超声压电换能器辐射声场分布进行了数值计算,分析了圆台换能器几何参数小端半径b、大端半径a以及高度h对轴向声场以及焦平面声场分布的影响。结果表明:圆台型自聚焦超声换能器轴向声场为振荡分布,声强平均值较高,存在一组最佳参数对应于最佳的聚焦效果,而径向声场分布比较均匀,焦平面有效半径小,受参数影响较小。

关键词：压电换能器超声圆台声场

Quantum public-key crypto via EPR pairs

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 58-63页

作者： xiang-Qun Fu hong-Wei Li Jian-hong Shi Tan Li Wan-Su Bao Henan Key Laboratory of Quantum Information and Cryptography Information Engineering University Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China

With the development of quantum computing technology, quantum public-key cryptography is gradually becoming an alternative to the existing classical public-key cryptography. This paper designs a quantum trapdoor one-way function via EPR pairs and quantum measurements. Based on this, a new quantum public-key cryptosystem is presented, which offers forward security,and can resist the chosen-plaintext attack and chosen-ciphertext attack. Compared with the existing quantum public-key cryptos,eavesdropping can be automatically detected in this new quantum public-key cryptosystem under a necessary condition, which is also detailed in the paper.

关键词： quantum public-key crypto trapdoor one-way function EPR pairs

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软土固结试验数值模拟

岩土力学 2013年第S2期34卷 407-412,420页

作者：刘洋王喆闫鸿翔北京科技大学土木与环境工程学院土木工程系北京100083

基于太沙基一维固结理论,采用有限差分法对室内固结试验进行了数值分析,编制了室内固结试验的C++数值程序和自动求解固结系数的Matlab拟合程序,该程序能够模拟不同尺寸(排水高度)软土试样的固结过程。讨论了试样尺寸、渗透系数和初始固... 详细信息

基于太沙基一维固结理论,采用有限差分法对室内固结试验进行了数值分析,编制了室内固结试验的C++数值程序和自动求解固结系数的Matlab拟合程序,该程序能够模拟不同尺寸(排水高度)软土试样的固结过程。讨论了试样尺寸、渗透系数和初始固结应力对模拟结果的影响。数值结果显示随着排水高度和渗透系数的增加,由时间平方根法和时间对数法求解的固结系数比不断减小,且排水高度较小时固结系数比变化较快。土体初始应力越小,主固结完成所需的时间越长。与日本广岛重塑土大尺寸试样固结试验结果进行了比较分析。研究结果表明所采用的数值方法能够较好地模拟软土的固结试验过程,可以进行一定条件下大尺寸软土试样的固结特性研究,研究成果对于揭示软土的固结变形发展有一定的理论价值和实际意义。

关键词：软土固结试验数值模拟排水高度

Preparation and electrochemical property of Cs0.35V2O5/Cu composite material

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Journal of Chemistry and Chemical Engineering 2008年第6期2卷 52-55页

作者： CAO Xiao-yu yanG Jun XIE Ling-ling LIU Xing WANG hong-yan yan xiang-yang School of Chemistry and Chemical Engineering Henan University of Technology Zhengzhou 450001 China

Cs0.35V2O5 was successfully synthesized as cathode material for lithium secondary battery by the rheological phase reaction method from Cs2CO3 and NH4VO3. The Cs0.35V2O5/Cu composite material was prepared by the displacement reaction in CuSO4 solution using zinc powder as a reductant. The structure and electrochemical property of the so-prepared powders were characterized by means of XRD （powder X-ray diffraction） and the galvanostatic discharge-charge techniques. The results show that the electrochemical property of Cs0.35V2O5/Cu composite material is significantly improved compared to the bulk Cs0.35V2O5 material. The Cs0.35V2O5/Cu composite material exhibits the first discharge capacity as high as 164.3 mAh.g -1 in the range of 4.2-1.8V at a current rate of 10 mA.g-1 and remains at a stable discharge capacity of about 110 mAh.g-1 within 40 cycles.

关键词： lithium secondary batteries cathode material Cs0.35V2O5/Cu composite material electrochemical property

基于经验模态分解及独立成分分析的微震信号降噪方法

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地球物理学报 2015年第3期58卷 1013-1023页

作者：贾瑞生赵同彬孙红梅闫相宏山东科技大学信息科学与工程学院青岛266590 山东科技大学矿山灾害预防控制省部共建国家重点实验室培育基地青岛266590 山东科技大学矿业与安全工程学院青岛266590

针对微震信号具有高噪声、突变快、随机性强等特点,基于经验模态分解(EMD)及独立成分分析(ICA)提出一种微震信号降噪方法.首先,对含噪信号进行EMD分解,获得一系列按频率从高到低的内蕴模态函数(IMF),利用原信号与各IMF之间的互相关系数... 详细信息

针对微震信号具有高噪声、突变快、随机性强等特点,基于经验模态分解(EMD)及独立成分分析(ICA)提出一种微震信号降噪方法.首先,对含噪信号进行EMD分解,获得一系列按频率从高到低的内蕴模态函数(IMF),利用原信号与各IMF之间的互相关系数辨识出噪声与信号的分界,将分界之上的高频噪声滤除;其次,为有效去除分界IMF中的模态混叠噪声,基于ICA算法对分界IMF进行盲源分离,提取其中的微震有效信号,并将其与剩余的IMF累加重构,从而得到降噪后的微震信号;最后,利用快速傅里叶变换(FFT)时频谱对比分析降噪前后的信号特征,定性说明本文方法的有效性;引入信噪比和降噪后信号占原信号的能量百分比两个参数,定量说明本文方法能充分保留微震信号的瞬态非平稳特征,降噪效果明显.

关键词：微震信号降噪经验模态分解独立成分分析互相关

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复合振冲碎石桩加固机理及施工过程数值模拟

工程科学学报 2015年第3期37卷 390-397页

作者：刘洋闫鸿翔汪成林北京科技大学土木与环境工程学院北京100083 北京科技大学金属矿山高效开采与安全教育部重点实验室北京100083 中国公路工程咨询集团有限公司北京100097

采用振动荷载作用下超孔隙水压力产生的能量模型,考虑耗散能量和孔径扩张的影响及相互作用,并进行合理的简化,对复合振冲碎石桩施工过程做了数值模拟.采用有限差分离散求解复合振冲碎石桩边值问题,编制相应的数值程序,基于模拟结果详细... 详细信息

采用振动荷载作用下超孔隙水压力产生的能量模型,考虑耗散能量和孔径扩张的影响及相互作用,并进行合理的简化,对复合振冲碎石桩施工过程做了数值模拟.采用有限差分离散求解复合振冲碎石桩边值问题,编制相应的数值程序,基于模拟结果详细讨论了排水井的存在对复合振冲碎石桩孔隙水压力发展变化的影响.最后对普通碎石桩和复合碎石桩的地基加固效果进行对比分析.数值模拟结果表明,复合振冲碎石桩由于排水井的存在,使地基加固范围明显增大,并且可以应用于渗透系数较小的粉土和砂质粉土地基中.

关键词：地基加固桩相对密度数值模拟

基于网络的煤矿巷道顶板离层计算机监测预报系统研究

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矿业安全与环保 2008年第6期35卷 29-30,33页

作者：张勇闫相宏宋扬山东科技大学资源与环境工程学院山东青岛266510 泰山医学院放射学院山东泰安271000

开发了基于工业以太网的顶板离层计算机监测系统,用于煤矿回采或掘进巷道顶板离层的在线监测。通过位移传感器监测顶板离层的位置、离层速度变化,能动态地掌握顶板运动过程,对可能发生的顶板事故提前预警。实践证明,该监测系统的各项指... 详细信息

开发了基于工业以太网的顶板离层计算机监测系统,用于煤矿回采或掘进巷道顶板离层的在线监测。通过位移传感器监测顶板离层的位置、离层速度变化,能动态地掌握顶板运动过程,对可能发生的顶板事故提前预警。实践证明,该监测系统的各项指标达到了设计要求,其成功应用促进了煤矿的安全、高效生产,取得了明显的经济效益和社会效益。

关键词：顶板离层在线监测工业以太网相对位移量