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碎裂QRS波在诊断急性心肌梗死中的应用价值

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中外医疗 2016年第24期35卷 189-190,193页

作者：关秀兰朱可云陈华发邓月娟李小梅广东省江门市新会区人民医院电生理科广东江门529100 广东省江门市新会区人民医院心内科广东江门529100

目的探讨心电图碎裂QRS波(f QRS波)在诊断急性心肌梗死(AMI)的应用价值。方法方便选取该院2010年1月—2015年6月经冠脉造影确诊的急性心肌梗死患者90例与非AMI患者进行对比分析,又根据患者是否存在f QRS或病理性Q波分组,分析f QRS波的... 详细信息

目的探讨心电图碎裂QRS波(f QRS波)在诊断急性心肌梗死(AMI)的应用价值。方法方便选取该院2010年1月—2015年6月经冠脉造影确诊的急性心肌梗死患者90例与非AMI患者进行对比分析,又根据患者是否存在f QRS或病理性Q波分组,分析f QRS波的分布特性及价值性。结果 1下壁出现f QRS的机率(12.22%)较前壁、侧壁(5.6%)、3.3%)高。2病理性Q波(25.56%)敏感性略高于f QRS波者(21.11%),但病理性Q波者(88.89%和69.70%)均低于f QRS波者特异性(95.56%)及阳性预测值(82.60%);当两者结合应用时,敏感性和特异性、阳性预测值、阴性性预测值(41.11%、96.67%、92.50%、62.14%)均较高。3在NSTEMI患者中f QRS(38.10%)发生率明显高于病理Q波(14.29%),f QRS与f QRS合并病理性Q波对比差异有统计学意义(P<0.05)。结论f QRS波对NSTEMI有一定的诊断价值,可作为心电图诊断急性心肌梗死的一个新指标。

关键词：碎裂QRS波病理性Q波急性心肌梗死

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Mn基低温脱硝催化剂性能优化研究进展

工程科学学报 2025年第1期47卷 142-157页

作者：许芸邬博宇庄柯张乾徐静馨张深根朱法华张柏林国家能源集团科学技术研究院有限公司低碳智能燃煤发电与超净排放全国重点实验室南京210023 北京科技大学新材料技术研究院北京100083

氮氧化物(NO_(x))是我国首要大气污染物,主要采用选择性催化还原(SCR)技术进行排放控制.研发高效、稳定的低温脱硝催化剂可避免高能耗的烟气再热,具有显著的节能降碳效益.锰氧化物(MnO_(x))因多变的化学态和丰富的晶格缺陷而表现出优良... 详细信息

氮氧化物(NO_(x))是我国首要大气污染物,主要采用选择性催化还原(SCR)技术进行排放控制.研发高效、稳定的低温脱硝催化剂可避免高能耗的烟气再热,具有显著的节能降碳效益.锰氧化物(MnO_(x))因多变的化学态和丰富的晶格缺陷而表现出优良的氧化还原性能,并具有极强的表面酸性,在催化还原NO_(x)反应中表现出良好的低温活性,但N_(2)选择性低、抗H_(2)O/SO_(2)性能差,难以实现长期的高效稳定脱硝.近年来,改性提升Mn基催化剂的研究十分广泛,加快了Mn基催化剂工业应用的步伐.本文从低温活性、N_(2)选择性和稳定性三个方面,总结了Mn基催化剂的脱硝反应机理、元素掺杂改性、催化剂结构设计等最新研究进展,指出了当前的研究重点和难点,可为下一步研究提供参考.

关键词：氮氧化物选择性催化还原锰基催化剂 N2选择性稳定性元素掺杂

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微波辐射计对昆明雾天的监测及应用

成都信息工程大学学报 2018年第1期33卷 54-61页

作者：欧映瑜朱克云张杰郑佳锋谢慧玲成都信息工程大学大气科学学院高原大气与环境四川省重点实验室四川成都610225

为分析微波辐射计在雾天探测的气象应用价值,利用昆明机场HTG-4型微波辐射计2016年1-4月的探测数据,参照同址测站逐小时天气纪要,将昆明雾天分为锋面雾和辐射雾两种天气实例,分别从温湿、水汽含量等方面对雾天的监测和分析进行研究。结... 详细信息

为分析微波辐射计在雾天探测的气象应用价值,利用昆明机场HTG-4型微波辐射计2016年1-4月的探测数据,参照同址测站逐小时天气纪要,将昆明雾天分为锋面雾和辐射雾两种天气实例,分别从温湿、水汽含量等方面对雾天的监测和分析进行研究。结果表明:(1)辐射计温度的高度廓线随时间的变化能较准确地反映静止锋锋区的空间结构及随时间的演变特征,近地面逆温层的生消与机场辐射雾发生发展消亡的过程吻合;(2)在大雾发生之前,辐射计显示机场区域从地面到空中的相对湿度和绝对湿度都保持在大值区;(3)液态水廓线的变化能反映出雾天发生过程中冷暖平流的变化情况;(4)在大雾发生前半小时,液态水路径会发生突变,综合水汽含量也保持在大值区,可作为预报大雾发生时的重要标准。

关键词：应用气象短临天气预报微波辐射计锋面雾辐射雾温湿数据监测长水机场预报

Well-ordered layered LiNi0.8Co0.1Mn0.1O2 submicron sphere with fast electrochemical kinetics for cathodic lithium storage

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Journal of Energy Chemistry 2020年第8期29卷 188-195,I0007页

作者： Jianing Liang yun Lu Jie Wang Xupo Liu ke Chen Weihao Ji Ye zhu Deli Wang key laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina College of Chemistry and Pharmaceutical Sciences Qingdao Agricultural UniversityQingdao 266109ShandongChina Department of Applied Physics The Hong Kong Polytechnic UniversityHong Kong 999077China

Nickel-rich layered oxides have drawn sustainable attentions for lithium ion batteries owing to their higher theoretical capacities and lower ***,nickel-rich layered oxides also have exposed several defects for commercial application,such as uncontrollable ordered layered structure,which leads to higher energy barrier for Li+*** addition,suffering from structural mutability,the bulk nickelrich cathode materials likely trigger overall volumetric variation and intergranular cracks,thus obstructing the lithium ion diffusion path and shortening the service life of the whole ***,we report wellordered layered Li Ni0.8Co0.1Mn0.1O2 submicron spheroidal particles via an optimized co-precipitation and investigated as LIBs cathodes for high-performance lithium *** as-fabricated Li Ni0.8Co0.1Mn0.1O2 delivers high initial capacity of 228 mAh g–1,remarkable energy density of 866 Wh kg–1,rapid Li ion diffusion coefficient(10–9cm2s–1)and low voltage *** remarkable electrochemical performance should be ascribed to the well-ordered layered structure and uniform submicron spheroidal particles,which enhance the structural stability and ameliorate strain relaxation via reducing the parcel size and shortening Li-ion diffusion *** work anticipatorily provides an inspiration to better design particle morphology for structural stability and rate capability in electrochemistry energy storage devices.

关键词： Lithium ion batteries Nickel-rich cathode Well-ordered layered structure Submicron spheroidal particles Electrochemical kinetics

A micro-chip exploding foil initiator based on printed circuit board technology

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Defence Technology（防务技术） 2022年第8期18卷 1435-1444页

作者： Zhi Yang Peng zhu Qing-yun Chu Qiu Zhang ke Wang Hao-tian Jian Rui-qi Shen School of Chemical Engineering Nanjing University of Science and TechnologyNanjing210094China Micro-Nano Energetic Devices key Laboratory Ministry of Industry and Information TechnologyNanjing210094China

Conventional exploding foil initiator (EFI) in ignition or detonation applications hosts many performance advantages, but was hindered by the bulky, inaccurate, inefficient and expensive shortcomings. We highlight a novel micro-chip exploding foil initiator (McEFI) using printed circuit board (PCB) technology. The structural parameters were determined based on energy coupling relationship at the component interfaces. Next, the prototype McEFI has been batch-fabricated using PCB technology, with a monolithic structure of 7.0 mm (l) × 4.5 mm (w) × 4.0 mm (δ). As expected, this PCB-McEFI illustrated the successful firing validations for explosives pellets. This paper has addressed the cost problem in both military munitions and civil markets wherever reliable, insensitive and timing-dependent ignition or detonation are involved.

关键词： Exploding foil initiator Printed circuit board Monolithic structure Firing validations

A note on the definition of fractional derivatives applied in rheology

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Acta Mechanica Sinica 2011年第6期27卷 866-876页

作者： Fan Yang ke-Qin zhu Department of Engineering Mechanics Tsinghua University 100084 Beijing China

It is known that there exist obivious differences between the two most commonly used definitions of fractional derivatives-Riemann-Liouville （R-L） definition and Caputo definition. The multiple definitions of fractional derivatives in fractional calculus have hindered the application of fractional calculus in rheology. In this paper, we clarify that the R-L definition and Caputo definition are both rheologically imperfect with the help of mechanical analogues of the fractional element model （Scott-Blair model）. We also clarify that to make them perfect rheologically, the lower terminals of both definitions should be put to ∞. We further prove that the R-L definition with lower terminal a →∞ and the Caputo definition with lower terminal a →∞ are equivalent in the differentiation of functions that are smooth enough and functions that have finite number of singular points. Thus we can define the fractional derivatives in rheology as the R-L derivatives with lower terminal a →∞ （or, equivalently, the Caputo derivatives with lower terminal a →∞） not only for steady-state processes, but also for transient processes. Based on the above definition, the problems of composition rules of fractional operators and the initial conditions for fractional differential equations are discussed, respectively. As an example we study a fractional oscillator with Scott-Blair model and give an exact solution of this equation under given initial conditions.

关键词： Fractional derivatives Rheology Riemann-Liouville definition Caputo definition

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风廓线雷达部署原则及北京地区应用分析

气象研究与应用 2015年第3期36卷 86-90,98页

作者：范艺何毅张杰朱克云许五保罗辉颜玉倩成都信息工程学院大气科学学院和高原大气与环境四川省重点实验室中国人民解放军96211部队成都军区空军气象中心北京爱尔达电子设备有限公司

从风廓线雷达的探测原理以及气象、环保、航空等行业的需求出发,借鉴国外风廓线雷达布网经验,讨论了部署的一般原则,主要从地形地貌、天气系统的影响路径以及污染源监测等方面分析了北京地区风廓线雷达部署方案的优势并针对不足提出了建... 详细信息

从风廓线雷达的探测原理以及气象、环保、航空等行业的需求出发,借鉴国外风廓线雷达布网经验,讨论了部署的一般原则,主要从地形地貌、天气系统的影响路径以及污染源监测等方面分析了北京地区风廓线雷达部署方案的优势并针对不足提出了建议,主要结论有:(1)风廓线雷达的部署应充分考虑应用目的,并针对不同天气系统的监测和使用领域的差异进行选型;(2)地形地貌、不同移动路径天气系统的权重影响以及对污染物扩散的监测等都是进行风廓线雷达部署的重要参考指标;(3)风廓线雷达局地布网应考虑与全局组网的需求接轨;(4)保持适当数量的机动式风廓线雷达,应对可能出现的异常情况。

关键词：风廓线雷达部置原则布网应用分析

Effect of Ti Additions on Mechanical and Thermodynamic Properties of W-Ti Alloys:A First-principles Study

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期 246-257页

作者：张建 NIE Wei HUANG Jin zhu ke LIU Ruxia 张睿智 LUO Guoqiang SHEN Qiang State key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Institute for Carbon Neutrality University of Science and Technology Beijing

The mechanical and thermodynamic properties of W-Ti alloys (including W15Ti1,W14Ti2,W12Ti4and W8Ti8alloys) were investigated by the first-principles approach based on density functional *** results indicate that W-Ti alloys except W8Ti8are thermodynamically *** modulus and hardness of W-Ti alloys are smaller than those of pure tungsten and gradually decrease with increasing Ti ***,their B/G ratios and Poisson's ratios exceed those of pure tungsten,suggesting that the introduction of Ti decreases the mechanical strength while enhancing the ductility of W-Ti *** thermal expansion coefficients for W-Ti alloys all surpass those of pure tungsten,indicating that the introduction of titanium exacerbates the thermal expansion behavior of W-Ti ***,elevated pressure has the capacity to suppress the thermal expansion tendencies in titanium-doped tungsten *** study offers theoretical insights for the design of nuclear materials by exploring the mechanical and thermodynamic properties of W-Ti alloys.

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新一代宽带移动通信系统安全威胁和安全需求分析

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信息工程大学学报 2010年第5期11卷 565-567页

作者：刘彩霞季新生彭建华俞定玖朱可云信息工程大学信息工程学院河南郑州450002

新一代宽带移动网络是一种以IP骨干网为承载,并支持多种接入方式的异构网络,这种结构在为用户的使用带来方便的同时,也引入了多种安全威胁。文章基于宽带移动通信网络中网络架构、业务类型等方面呈现的新特点,分析宽带移动网络面临的安... 详细信息

新一代宽带移动网络是一种以IP骨干网为承载,并支持多种接入方式的异构网络,这种结构在为用户的使用带来方便的同时,也引入了多种安全威胁。文章基于宽带移动通信网络中网络架构、业务类型等方面呈现的新特点,分析宽带移动网络面临的安全威胁与安全需求。

关键词：宽带移动通信全IP 异构网络