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N-Doped Carbon Nanofibers Encapsulating CoO@Co_(9)S_(8) Nanoparticles:Preparation from S-Rich Co_(32) Coordination Cluster Precursors by Electrospinning and Application for Superior li-ion Storage

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Chemical Research in Chinese Universities 2022年第2期38卷 603-608页

作者： YANG Siran AI Feixue li ziping ZHAO Guiyan BI Yanfeng School of Petrochemical Engineering Liaoning Petrochemical UniversityFushun 113001P.R.China

Thiacalixarene-supported Co_(32) nanoclusters encapsulated in polyacrylonitrile nanofibers(Co_(32)@PAN-NFs)by electrospinning have been utilized as precursors to fabricate N-doped CoO@Co_(9)S_(8) carbon nanofibers(CoO@Co_(9)S_(8)@CNFs)for superior li-ion *** S-rich Co_(32) clusters capped by organic sheets afforded the well dispersed cobalt oxide/sulfide nanoparticles embedded in carbon nanofiber composites by direct *** N-doped CoO@Co_(9)S_(8)@CNFs nanocomposites have been utilized as anode materials for lithium ion battery with the reversible capabilities being of 1051.8,967.6,894.7,782.7,669.5 and 525.4 mA·h/g at 0.1,0.2,0.5,1,2 and 3 A/g,*** CoO@Co_(9)S_(8)@CNFs also showed a relatively high stable capacity of 551.7 mA·h/g at the current density of 1 A/g after 200 cycles of rate *** as-obtained N-doped CoO@Co_(9)S_(8)@CNFs nanocomposites exhibited superior reversible capacity,rate performance,Coulomb efficiency(74.5%vs.63.9%)and cyclic stability comparing with the CoO@Co_(9)S_(8)@C derived from simple annealing of Co_(32) templates.

关键词： Metal cluster precursor Carbon nanofiber Electrospinning li-ion storage

中子符合计数研究中^(252)Cf源强的影响分析

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核科学与工程 2024年第1期44卷 17-24页

作者：李多宏李自平杨海峰邵增申鹏飞谭西早韩叶良国家核安保技术中心北京102401 中国核电工程有限公司北京100840 清华大学工程物理系北京100084

具有中子多重性的^(252)Cf源是中子符合计数实验测量和装置标定的首选。本文利用数值模拟手段研究^(252)Cf源强对中子符合计数的影响。根据中子符合计数实验的数据处理方法,通过生成带自发裂变事件标签的中子脉冲序列,按照移位寄存器的... 详细信息

具有中子多重性的^(252)Cf源是中子符合计数实验测量和装置标定的首选。本文利用数值模拟手段研究^(252)Cf源强对中子符合计数的影响。根据中子符合计数实验的数据处理方法,通过生成带自发裂变事件标签的中子脉冲序列,按照移位寄存器的数据处理逻辑对中子脉冲序列进行处理,给出中子符合测量模拟结果。基于对不同源强下前景(R+A)和背景(A)的中子多重性分布的模拟结果,定量分析源强对真符合计数在前景测量结果中占比的影响。结果表明,在^(252)Cf源强为每秒几百或几千个中子时,真符合计数在R+A的中子符合计数中占绝对或明显优势(超过50%),推荐作为实验的中子源;源强为每秒几万个中子时,真符合计数在R+A的中子符合计数中占比约10%;源强达到每秒几十万个中子时,真符合计数淹没在偶然符合计数中(占比约1%),不建议用作实验的中子源。本文的研究可以为实验的源强选择、实验数据的有效性检查提供一个参考。

关键词：中子符合计数源强影响 ^(252)Cf源

Recent Advances of Covalent Organic Frameworks for Chiral Separation

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Chemical Research in Chinese Universities 2022年第2期38卷 350-355页

作者： HOU Bang li ziping KANG Xing JIANG Hong CUI Yong School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative Molecules and State Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240P.R.China

Covalent organic frameworks(COFs), orderly assembled from the building blocks via covalent bonds, are a novel type of porous materials with rich functional sites and permanent porosity. At present, most of COFs are achiral networks, nevertheless, chiral COFs(CCOFs) have become a research hotspot in recent years, due to their unique chiral sites and microenvironment. As one of the most important applications of CCOFs, chiral separation has attracted huge attention for the convenient, rapid and efficient feature. In this review, recent progresses of covalent organic frameworks for chiral separation are covered. And we also present the challenges and outlooks of CCOFs in the future for this field.

关键词： Covalent organic framework Chirality Separation

Antithrombotic therapy and bleeding risk in the era of aggressive lipid-lowering:current evidence,clinical implications,and future perspectives

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Chinese Medical Journal 2023年第6期136卷 645-652页

作者： Xin Zhou ziping li Hangkuan liu Yongle li Dong Zhao Qing Yang Department of Cardiology Tianjin Medical University General HospitalTianjin 300052China Department of Epidemiology Beijing Anzhen HospitalCapital Medical UniversityBeijing 100029Institute of HeartLung and Blood Vessel DiseasesBeijing 100029China

The clinical efficacy of proprotein convertase subtilisin/kexin type 9 inhibitors(PCSK9i)in reducing major cardiovascular adverse events related to atherosclerotic cardiovascular disease(ASCVD)has been well established in recent large randomized outcome *** the cardiovascular and all-cause mortality benefit of PCSK9i remains inconclusive,current cholesterol management guidelines have been modified toward more aggressive goals for lowering low-density lipoprotein cholesterol(LDL-C).Consequently,the emerging concept of"the lower the better"has become the paradigm of ASCVD ***,there is evidence from observational studies of a U-shaped association between baseline LDL-C levels and all-cause mortality in population-based *** East Asian populations,low LDL-C was associated with an increased risk for hemorrhagic stroke in patients not on antithrombotic *** evidence showed that low LDL-C was associated with an enhanced bleeding risk in patients on dual antiplatelet therapy following percutaneous coronary ***,low LDL-C was associated with a higher risk for incident atrial fibrillation and thereby,a possible increase in the risk for intracranial hemorrhage after initiation of anticoagulation *** mechanism of low-LDL-C-related bleeding risk has not been fully *** review summarizes recent evidence of low-LDL-C-related bleeding risk in patients on antithrombotic therapy and discusses potential measures for reducing this risk,underscoring the importance of carefully weighing the pros and cons of aggressive LDL-C lowering in patients on antithrombotic therapy.

关键词： Cholesterol-lowering drugs Bleeding Antithrombotic LDL cholesterol Proprotein convertase subtilisin/kexin type 9 inhibitors

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基于电荷泵DC-DC转换器的开关电源设计

现代工业经济和信息化 2024年第2期14卷 127-129页

作者：陈逸飞李校良李梓萍闫泓全金书池辽宁工程技术大学电气与控制工程学院辽宁葫芦岛125000

设计了一种成本较低,效率较高的基于电荷泵与Boost升压电路的开关电源,作用于对正负双电源运放供电。利用Boost模块将3~4.5 V的输入电压升压至稳定的5.5 V电压,并通过电荷泵负压电路、电荷泵倍压电路与TL431串联稳压电路将5.5 V的电压... 详细信息

设计了一种成本较低,效率较高的基于电荷泵与Boost升压电路的开关电源,作用于对正负双电源运放供电。利用Boost模块将3~4.5 V的输入电压升压至稳定的5.5 V电压,并通过电荷泵负压电路、电荷泵倍压电路与TL431串联稳压电路将5.5 V的电压转化为±5 V的输出电压为运放进行供电。通过仿真软件对电路进行仿真搭建,并对重要节点与输出电压电流的仿真波形进行分析,确保在3~4.5 V的DC输入电压范围内,提供较为稳定的、输出电压纹波在2%以内的±5 V输出电压。

关键词：电荷泵负压 Boost升压电路开关电源

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基于粒子群算法优化神经网络的短期负荷预测

现代工业经济和信息化 2024年第6期14卷 138-140页

作者：李校良陈逸飞李梓萍闫泓全雷帅帅辽宁工程技术大学辽宁葫芦岛125000

基于粒子群算法(PSO)的神经网络在短期负荷预测中展现出卓越的效果。通过PSO神经网络的权重和偏置得以有效优化,使其更快、更准确地学习并适应电力系统的负荷变化。该方法通过随机初始化一群“粒子”,每个粒子代表神经网络的一组参数,... 详细信息

基于粒子群算法(PSO)的神经网络在短期负荷预测中展现出卓越的效果。通过PSO神经网络的权重和偏置得以有效优化,使其更快、更准确地学习并适应电力系统的负荷变化。该方法通过随机初始化一群“粒子”,每个粒子代表神经网络的一组参数,然后通过迭代更新粒子位置,实现了对神经网络模型的全局搜索和优化。研究结果表明,经PSO优化的神经网络在短期负荷预测中呈现出更高的拟合度,与实际负荷曲线更为贴近,且相较于传统神经网络,其预测误差显著降低。这一方法为电力系统提供了一种可靠的工具,有效提升了短期负荷预测的准确性和可靠性。

关键词：短期负荷预测粒子群算法神经网络

Terahertz metalens of hyper-dispersion

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Photonics Research 2022年第4期10卷 886-895页

作者： Fen Zhao ziping li Sheng li Xuemei Dai Yi Zhou Xiaoyu liao JCCao Gaofeng liang Zhengguo Shang Zhihai Zhang Zhongquan Wen Hua li Gang Chen Key Laboratory of Optoelectronic Technology and Systems(Chongqing University) Ministry of EducationSchool of Optoelectronic EngineeringChongqing UniversityChongqing 400044China Key Laboratory of Terahertz Solid State Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China

Chromatic optical lenses have promising applications in three-dimensional imaging, which allows fast spectral tomography without mechanical moving parts. The scanning range of current chromatic optical lenses is limited by their dispersion ability. The recent development in metasurfaces provides ideal blocks for optical wavefront manipulation and dispersion engineering of artificial materials at sub-wavelength scales. Hyper-dispersive metalenses can be realized by utilizing dispersive meta-atoms, which have enhanced dispersion compared to regular diffractive lenses. This is critical for increasing the imaging depth of fast spectral tomography. In this work, a hyper-dispersive metalens is realized with a chromatic dispersion 1.76 times greater than that of a regular diffractive metalens in the THz frequency range of 2.40–2.61 THz by simultaneously controlling the frequencydependent phase, group delay(GD), and GD dispersion of the metalens. This approach can also be extended to other optical spectra and improve the performance of spectral tomography.

关键词： dispersion moving chromatic

全域实景视频监控技术在核设施实物保护系统中的应用探索

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世界核地质科学 2024年第2期41卷 396-404页

作者：唐文偲袁潮何佳霖付嘉佳李多宏李自平陈芳雷赵国海宗波李达国家核安保技术中心北京102401 北京拙河科技有限公司北京100080

视频监控系统一直是核设施实物保护系统的重要组成部分,监控视频的覆盖率、清晰度和准确性等也是检验核设施实物保护系统有效性的一个重要指标。大场景超亿级像素的全域实景视频监控系统是一种全天候、自动化和智能化的视频监控系统,在... 详细信息

视频监控系统一直是核设施实物保护系统的重要组成部分,监控视频的覆盖率、清晰度和准确性等也是检验核设施实物保护系统有效性的一个重要指标。大场景超亿级像素的全域实景视频监控系统是一种全天候、自动化和智能化的视频监控系统,在其他安防领域有着广泛的应用,拥有一定的技术积累,为解决现有核设施实物保护视频监控系统存在的问题提供了一种新的技术方案。通过对全域实景视频监控系统的整体架构、软件算法和技术特点进行分析,结合当前核设施实物保护系统中视频监控的需求和问题提出了全域实景视频监控未来的发展趋势。

关键词：全域实景视频监控监控系统亿级像素核设施实物保护

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不同工艺对六堡茶香气及品质成分的影响

农业研究与应用 2024年第1期37卷 14-22页

作者：庞师婵刘宝贵梁光志赵云雄覃仁源李子平广西南亚热带农业科学研究所广西崇左532145 广西农业职业技术大学广西南宁530009

以‘云南大叶种’(Camellia sinensis ***)和‘金萱’两种茶树品种的一芽二叶鲜叶为原料,使用传统工艺与现代工艺加工得出的四款六堡茶,经仓储1年后作为研究对象,对该批次茶样进行理化分析对比,探索两种工艺制作的六堡茶的品质差异。结... 详细信息

以‘云南大叶种’(Camellia sinensis ***)和‘金萱’两种茶树品种的一芽二叶鲜叶为原料,使用传统工艺与现代工艺加工得出的四款六堡茶,经仓储1年后作为研究对象,对该批次茶样进行理化分析对比,探索两种工艺制作的六堡茶的品质差异。结果表明:经仓储1年后,现代工艺制作的六堡茶在感官审评中,在外形、汤色、香气、滋味及叶底等方面均优于传统工艺;在内含物方面,传统工艺制作的六堡茶的游离氨基酸、茶多酚、茶红素含量均高于现代工艺,而水浸出物、茶黄素、茶褐素的含量则低于现代工艺;在香气成分上,传统工艺和现代工艺制作的六堡茶共检测出92种挥发性香气成分,传统工艺主要成分以醇类、醛类为主,现代工艺主要成分以酮类、醛类为主。综上所述,现代工艺的冷水渥堆在一定程度上加快了六堡茶后发酵,使得茶叶中茶褐素增加,茶汤颜色短时间内迅速由黄转红;同时,由于茶多酚含量降低,使茶汤苦涩味降低,滋味更加醇。因此,随着六堡茶市场需求的不断扩大,利用现代工艺的冷水渥堆工艺可以缩短陈化时长,降低茶企仓储成本,使六堡茶能迅速走向市场。

关键词：六堡茶现代工艺传统工艺内含物质

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