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Anomalous microstructure and tribological evaluation of AlCrFeNiW_(0.2)Ti_(0.5)high-entropy alloy coating manufactured by laser cladding in seawater

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Journal of Materials Science & Technology 2021年第26期85卷 224-234页

作者： hui liang Dongxu Qiao Junwei Miao Zhiqiang Cao hui Jiang Tongmin Wang Materials Science and Engineering Dalian University of TechnologyDalian116024China New Materials Innovation Center Ningbo Institute of Dalian University of TechnologyNingbo315000China College of Mechanical and Electronic Engineering Shandong University of Science and TechnologyQingdao266590China

To evaluate the potential of high entropy alloys for marine applications,a new high entropy alloy coating of AlCrFeNiW_(0.2)Ti_(0.5)was designed and produced on Q235 steel via laser *** microstructure,microhardness and tribological performances sliding against YG6 cemented carbide,GCr15 steel and Si_(3)N_(4)ceramic in seawater were studied in *** AlCrFeNiW_(0.2)Ti_(0.5)coating showed an anomalous’sunflower-like’morphology and consisted of BCC and ordered B2 *** microhardness was approximately 692.5 HV,which was 5 times higher than *** coating showed more excellent tribological performances than Q235 steel and SUS304,a typical material used in seawater environment,sliding against all three coupled balls in ***,the wear and friction of AlCrFeNiW_(0.2)Ti_(0.5)coating sliding against YG6 in seawater were most *** main reason was the generation of Mg(OH)_(2),CaCO_(3),metal oxides and hydroxides and the formation of protective tribo-film on the worn surface of AlCrFeNiW_(0.2)Ti_(0.5)coating in the process of reciprocated *** would effectively hinder the direct contact between the worn surfaces of AlCrFeNiW_(0.2)Ti_(0.5)coating and YG6 ball,resulting in a decrease of friction coefficient and wear *** the YG6 was an ideal coupled material for AlCrFeNiW_(0.2)Ti_(0.5)coating in seawater,and the coating would become a promising wear-resisting material in ocean environment.

关键词： High-entropy alloy coating Laser cladding Microstructure Microhardness Tribological properties

以旅游专业为例的广西与东盟国家职业教育合作发展实践路径研究

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中阿科技论坛（中英文） 2024年第9期 12-15页

作者：梁慧庞小峰姚志权广西工业技师学院广西南宁530031 广西壮族自治区人力资源和社会保障厅技工教育研究室广西南宁530021 广西壮族自治区人力资源和社会保障厅信息中心广西南宁530022

自2022年1月《区域全面经济伙伴关系协定》(RCEP)正式生效实施以来,中国与东盟经贸合作呈现更加紧密、活跃、全面、深入的发展局面。东盟已成为中国企业对外贸易投资的热门地区,中国与东盟之间的产业链供应链合作显示出较强韧性,并产生... 详细信息

自2022年1月《区域全面经济伙伴关系协定》(RCEP)正式生效实施以来,中国与东盟经贸合作呈现更加紧密、活跃、全面、深入的发展局面。东盟已成为中国企业对外贸易投资的热门地区,中国与东盟之间的产业链供应链合作显示出较强韧性,并产生了积极的外溢和示范效应。作为我国唯一同东盟海陆相连的省份,“一带一路”建设与RCEP生效实施,为广西更好地服务和融入新发展格局提供了历史性机遇。基于此,文章以旅游专业为例,在分析广西与东盟国家在职业教育的合作优势及典型实践案例的基础上,提出了建立紧密的校际合作机制,推动教育资源共享;深化校企合作,实现产学研一体化;创新合作模式,拓展合作领域等进一步提高广西与东盟国家职业教育合作发展水平的具体建议。

关键词：东盟国家职业教育旅游专业广西

纤维支气管镜吸痰联合肺泡灌洗治疗老年坠积性肺炎患者的效果及对氧合指数的影响

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系统医学 2024年第7期9卷 39-42页

作者：韩敏董志丹梁辉沛县人民医院重症医学科江苏徐州221600

目的探讨纤维支气管镜吸痰联合肺泡灌洗治疗坠积性肺炎患者的效果。方法选取2020年1月—2022年12月沛县人民医院重症医学科收治的60例重症肺部感染患者为研究对象,根据随机数表法分成两组,各30例。对照组实施常规治疗方法,观察组在对照... 详细信息

目的探讨纤维支气管镜吸痰联合肺泡灌洗治疗坠积性肺炎患者的效果。方法选取2020年1月—2022年12月沛县人民医院重症医学科收治的60例重症肺部感染患者为研究对象,根据随机数表法分成两组,各30例。对照组实施常规治疗方法,观察组在对照组基础上采用纤维支气管镜吸痰联合肺泡灌洗疗法,比较两组感染指标、动脉血气指标、肺部炎症吸收情况及不良反应发生情况。结果治疗后观察组患者血清C反应蛋白、降钙素原、白介素-6、二氧化碳分压低于对照组,差异有统计学意义(P均<0.05)。治疗后观察组患者的氧分压,氧合指数高于对照组,差异有统计学意义(P均<0.05);观察组的疗效为93.33%,优于对照组的73.33%,差异有统计学意义(χ^(2)=4.320,P<0.05)。治疗期间,两组未发生不良反应。结论纤维支气管镜吸痰联合肺泡灌洗治疗坠积性肺炎患者的辅助治疗,可改善动脉血气指标,降低炎症因子水平,并且不会增加不良反应的发生率,患者安全性和有效性能够得到保障。

关键词：坠积性肺炎纤维支气管镜吸痰肺泡灌洗抗菌药物

Observation of Near-Inertial Internal Waves on the Continental Slope in the Northwestern South China Sea

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Journal of Ocean University of China 2017年第2期16卷 184-190页

作者： ZHENG Jie TIAN Jiwei liang hui Physical Oceanography Laboratory Ocean University of ChinaQingdao 266100P.R.China

Based on nearly 3 months of moored acoustic Doppler current profiler records on the continental slope in the northwestern South China Sea(SCS) in 2006,this study examines temporal and vertical characteristics of near-inertial internal waves(NIW).Rotary frequency spectrum indicates that motions in the near-inertial frequency are strongly polarized,with clockwise(CW) energy exceeding counterclockwise(CCW) by about a factor of *** analysis exhibits an energy peak exceeding the 95% confidence level at the frequency of local inertial during the passage of typhoon Xangsane(24 September to 4 October).This elevated near-inertial kinetic energy(NIKE) event possesses about a 4 days delay correlation with the time integral of energy flux induced by typhoon,indicating an energy source of *** analysis shows that the upward phase velocity of this event is 3.8 m h^(-1)approximately,corresponding to a vertical wavelength of about 125 m if not taking the redshift of local inertial frequency into *** vertical wavenumber spectrum exhibits the dominance of clockwise-with-depth energy,indicating downward energy propagation and implying a surface energy *** modes suggest that mode 1 plays a dominant role at the growth stage of NIW,whereas major contribution is from higher modes during the penetration of NIKE into the ocean interior.

关键词： South China Sea near-inertial internal waves mooring

Spectral Gap for Open Jackson Networks

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Acta Mathematica Sinica,English Series 2015年第12期31卷 1879-1894页

作者： Yong Hua MAO liang hui XIA School of Mathematical Sciences LMCSMinistry of Education Beijing Normal University Department of Mathematics Ji'nan University

We generalize the decomposition method of the finite Markov chains for Poincare inequality in Jerrum et al.（***.,14,1741-1765（2004）） to the reversible continuous-time Markov *** inductively,we give the lower bound of spectral gap for the ergodic open Jackson network by the decomposition method and the symmetrization *** upper bound of the spectral gap is also presented.

关键词： Jackson networks reversibility decomposition of Markov chain spectral gap symmetrization

The Spectral Gap for Quasi-birth and Death Processes

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Acta Mathematica Sinica,English Series 2012年第5期28卷 1075-1090页

作者： Yong Hua MAO liang hui XIA School of Mathematical Sciences LMCSMinistry of EducationBeijing Normal University Department of Mathematics Ji'nan University

For a reversible quasi-birth and death process, we generalize and refine the decomposition method, by constructing a birth-death process and a sequence of restriction processes. The spectral gap for the quasi-birth and death process is estimated in terms of the spectral gaps for these processes, and in some special cases, the estimation is sharp. With the aid of the symmetrization procedure, the result is also applied to two queueing models： M/M/1 in random environment and MIMIc with synchronous vacation.

关键词： Quasi-birth and death process spectral gap birth-death process M/M/1 in random environment MIMIc with synchronous vacation

基于金属-绝缘体相变材料的高钝感集成半导体桥芯片设计

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火工品 2024年第2期 1-7页

作者：程鹏涛李慧骆建军冯春阳骆懿任炜梁小会杭州电子科技大学浙江杭州310018 陕西应用物理化学研究所瞬态化学效应与控制全国重点实验室陕西西安710061

为了提高半导体桥(SCB)火工品的安全性与可靠性,通过片上集成方式,在SCB两端并联金属-绝缘体相变材料VO_(2)对其进行分流防护。提出蛇形设计方法来降低VO_(2)薄膜在金属态的电阻值,使其与SCB阻值相匹配,测试了不同长宽比的VO_(2)薄膜及... 详细信息

为了提高半导体桥(SCB)火工品的安全性与可靠性,通过片上集成方式,在SCB两端并联金属-绝缘体相变材料VO_(2)对其进行分流防护。提出蛇形设计方法来降低VO_(2)薄膜在金属态的电阻值,使其与SCB阻值相匹配,测试了不同长宽比的VO_(2)薄膜及相应的集成芯片在室温(25℃)至100℃范围内的电阻曲线,并对集成芯片及单独SCB在1A1W5min和1.5A2.25W5min安流试验中的传热过程进行了仿真。结果表明:蛇形设计可以有效降低VO_(2)薄膜电阻,其阻值与蛇形长宽比(Ws/L)成反比;VO_(2)薄膜能够对SCB起到一定的分流防护作用;集成芯片尺寸对安流试验热传导过程的平衡温度有一定影响;能够通过1.5 A安流试验的最大VO_(2)阻值为5Ω,这是下一步的设计目标。

关键词：半导体桥(SCB) 二氧化钒(VO_(2)) 集成芯片电阻仿真

Symplectic Approach on the Wave Propagation Problem for Periodic Structures with Uncertainty

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Acta Mechanica Solida Sinica 2019年第3期32卷 287-297页

作者： Yan Zhao hui liang Youwei Zhang Jiahao Lin State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering Mechanics International Center for Computational Mechanics Dalian University of Technology Dalian 116023 China

An effective method is proposed in this paper for the symplectic eigenvalue problem of a periodic structure with uniform stochastic properties. Since structural parameters are uncertain, the symplectic transfer matrix of a typical substructure, which is described in the state space, also has sto chastic proper ties. An effec tive spec tral st ochastic finite elemen t method is adopted to ensure the symplectic orthogonality of the random symplectic matrix on the premise of certain precision. By means of the Rayleigh quotient method, the symplectic eigenvalue problem of random symplectic matrix is investigated. On the basis of this, the mean value and the standard deviation of the random eigenvalues are fully discussed. The comparison between the numerical results derived from the proposed method and the Monte-Carlo simulation indicates that the proposed method has high precision. This research provides a useful guidance for the dynamic analysis of periodic structures with stochastic properties.

关键词： Periodic structures Spectrum method Random symplectic matrix Symplectic eigenvalue

Research on Auto-detection for Remainder Particles of Aerospace Relay Based on Wavelet Analysis

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Chinese Journal of Aeronautics 2007年第1期20卷 75-80页

作者： GAO Hong-liang ZHANG hui WANG Shu-juan Department of Electrical Engineering Harbin Institute of Technology Harbin 150001 China

Aerospace relay is one kind of electronic components which is used widely in national defense system and aerospace system. The existence of remainder particles induces the reliability declining, which has become a severe problem in the development of aerospace relay. Traditional particle impact noise detection （PIND） method for remainder detection is ineffective for small particles, due to its low precision and involvement of subjective factors. An auto-detection method for PIND output signals is proposed in this paper, which is based on direct wavelet de-noising （DWD）, cross-correlation analysis （CCA） and homo-filtering （HF）, the method enhances the affectivity of PIND test about the small particles. In the end, some practical PIND output signals are analysed, and the validity of this new method is proved.

关键词： aerospace relay remainder particles PIND wavelet analysis