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Meta-analysis of the success rate of heartbeat recovery in patients with prehospital cardiac arrest in the past 40 years in China

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Military Medical Research 2020年第4期7卷 430-443页

作者： Xiang-min Gu shi-Bin Yao Zhong-Jie He yong-Gang Wang Zhi-Hui Li Tianjin Binhai New Area Center for Disease Control and Prevention Tianjin 300450China Emergency Department Affiliated Hospital of Chifeng CollegeChifeng 024005Inner MongoliaChina The Fourth Medical Center of Chinese PLA General Hospital Beijing 100048China Beijing Platinum Ten minutes Time-effect Emergency Technology Research Academy Beijing 100039China Beijing Chaoyang District Jiangtai Community Health Service Center Beijing 100016China

Background:Systematic evaluation of the successful heartbeat recovery rate(HRR)in patients during the platinum ten minutes after cardiac ***:The databases of CNKI(January 1979–March 2019),Chongqing VIP(January 1989–March 2019),Wanfang(January 1990–March 2019)and Web of Science(January 1900-May 2020)were *** collect the clinical data of patients with cardiac arrest before hospitalization and analyze the cardiopulmonary resuscitation(CPR)at different *** selection and data extraction were carried out by two researchers independently,and the meta package of R software(version 3.61)was used for ***:A total of 116 papers met the inclusion criteria,including 37,181 *** these patients,3367 had their heartbeats successfully *** results showed a high degree of heterogeneity(χ2=6999.21,Pmin group,the 5 to≤10 min group,the 10 to≤15 min group,and the>15 min *** HRR were 0.417(0.341–0.496),0.143(0.104–0.193),0.049(0.034–0.069),and 0.022(0.009–0.051),*** HRR was higher in the 0 to≤5 min group than in the 5 to≤10 min group,the 10 to≤15 min group and the>15 min *** was no difference between the 10 to≤15 min group and the>15 min group.(3)When the groups were stratified with the cutoff of 10 min,the≤10 min group HRR[0.250(0.202–0.306)]was higher than the>10 min group rate[0.041(0.029–0.057)].(4)The HRR of the telephone guidance group was[0.273(0.227–0.325)]lower than that of the 0 to≤5 min group[0.429(0.347–0.516)]but higher than that of the 5 to≤10 min group,the 1

关键词： Sudden cardiac arrest Cardiopulmonary resuscitation Peri-cardiac arrest period Platinum 10 min Meta-analysis

Recent progress of W_(18)O_(49)nanowires for energy conversion and storage

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Tungsten 2023年第4期5卷 371-390页

作者： Nan-Fu Yan Hong-min Cui Jin-Song shi Sheng-yong You Sheng Liu Institute of Applied Chemistry Jiangxi Academy of SciencesNanchang330096China Institute of New Energy Material Chemistry School of Materials Science and EngineeringRenewable Energy Conversion and Storage CenterNankai UniversityTianjin300350China

W_(18)O_(49)nanowires(W_(18)O_(49)NWs)with unique one-dimension structures and excellent electron/ions transport properties have attracted increasing attention in academia and industry because of their potential applications in many energy-related *** the past decades,many research articles related to W_(18)O_(49)have been published,but there are insufficient review articles focusing on W_(18)O_(49)*** this review,we present the crystal structure of W_(18)O_(49)and briefly introduce the synthesis methods and growth mechanism of W_(18)O_(49)***,their applications in energy conversion and storage devices are ***,the current challenges and opportunities for applying W_(18)O_(49)NWs are *** hope this review can promote the development of W_(18)O_(49)NWs in energy conversion,storage,and other promising applications.

关键词： W_(18)O_(49)nanowires Photovoltaic Rechargeable batteries Capacitors Fuel production

Distributed Cooperative Learning for Discrete-Time Strict-Feedback Multi Agent Systems Over Directed Graphs

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IEEE/CAA Journal of Automatica Sinica 2022年第10期9卷 1831-1844页

作者： min Wang Haotian shi Cong Wang IEEE the School of Automation Science and Engineering South China University of TechnologyGuangzhou 510641 Peng Cheng Laboratory Shenzhen 518055China the School of Control Science and Engineering Shandong UniversityJinan 250061China the Center for Intelligent Medical Engineering Shandong UniversityJinan 250061China

This paper focuses on the distributed cooperative learning(DCL)problem for a class of discrete-time strict-feedback multi-agent systems under directed *** with the previous DCL works based on undirected graphs,two main challenges lie in that the Laplacian matrix of directed graphs is nonsymmetric,and the derived weight error systems exist n-step *** novel lemmas are developed in this paper to show the exponential convergence for two kinds of linear time-varying(LTV)systems with different phenomena including the nonsymmetric Laplacian matrix and time ***,an adaptive neural network(NN)control scheme is proposed by establishing a directed communication graph along with n-step delays weight updating ***,by using two novel lemmas on the extended exponential convergence of LTV systems,estimated NN weights of all agents are verified to exponentially converge to small neighbourhoods of their common optimal values if directed communication graphs are strongly connected and *** stored NN weights are reused to structure learning controllers for the improved control performance of similar control tasks by the“mod”function and proper time series.A simulation comparison is shown to demonstrate the validity of the proposed DCL method.

关键词： Cooperative learning control directed graphs discrete-time nonlinear system neural networks(NNs) strict-feedback systems

A novel weld-pool-length monitoring method based on pixel analysis in plasma arc additive manufacturing

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Advances in Manufacturing 2024年第2期12卷 335-348页

作者： Bao-Ri Zhang yong-Hua shi Bionic Robot Research Department Ji Hua LaboratoryFoshan528200GuangdongPeople’s Republic of China Guangdong Provincial Engineering Research Center for Special Welding Technology and Equipment School of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou510640People’s Republic of China

The real-time monitoring of the weld pool during deposition is important for automatic control in plasma arc additive *** obtain a high deposition accuracy,it is essential to maintain a stable weld pool *** this study,a novel passive visual method is proposed to measure the weld pool *** the proposed method,the image quality was improved by designing a special visual system that employed an endoscope and a *** also includes pixel brightness-based and gradient-based algorithms that can adaptively detect feature points at the boundary when the weld pool geometry *** algorithm can also be applied to materials with different solidification *** was performed to measure the real weld pool length in world coordinates,and outlier rejection was performed to increase the accuracy of the ***,tests were carried out on the intersection component,and the results showed that the proposed method performed well in tracking the changing weld pool length and was applicable to the real-time monitoring of different types of materials.

关键词： Plasma arc additive manufacturing(PAAM) Weld pool geometry Gradient analysis Real-time detection

Synthesis and photocatalytic activity of TiO_2/conjugated polymer complex nanoparticles

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Chinese Chemical Letters 2008年第6期19卷 742-746页

作者： shi Xiong min Fang Wang Lei Feng yong Chun Tong Zi Rong Yang Department of Chemistry Key Laboratory of Resources and Environmental Chemistry of West China Hexi University Zhangye 734000 China

A photocatalyst of nanometer TiO2/conjugated polymer complex was successfully synthesized and characterized by spectroscopic methods and photocatalytic experiments. The complex photocatalyst could be activated by absorbing both ultraviolet and visible light （λ = 190-800 nm）. Methylene blue （MB） could be degraded more efficiently on the complex photocatalyst than on the TiO2 under natural light. The conjugated polymer played a promoting role in the photocatalytic degradation of MB. The calcination temperature had an important effect in degradation of dye and could be summarized as 260℃ 〉 300 ℃ 〉 340 ℃ 〉 220 ℃ 〉 180 ℃.

关键词： TiO2 Conjugated polymer Complex photocatalyst Methylene blue Degradation Natural light

Colloid of Delaminated Layered Double Hydroxides:a Novel Type of LDH-based Catalyst

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Chemical Research in Chinese Universities 2010年第4期26卷 612-616页

作者： LIU shi-yong Department of Chemistry Taizhou UniversityTaizhou 317000P.R.China Department of Chemistry Zhejiang UniversityHangzhou 310027P.R.China

The colloid of delaminated layered double hydroxides(LDHs), a new LDH-based catalyst, is described. The semi-heterogeneous delaminated colloidal MgPdA1-LDH, in which the total surface of catalytic site-bearing lamellae was rendered accessible for chemical reactivity, showed excellent catalysis toward Suzuki reaction. The turnover frequency of this catalyst for Suzuki reaction between bromobenzene and phenylboronic acid is about 8000 h^-1.

关键词： Layered double hydroxide(LDH) Colloid Delamination Suzuki reaction Semi-heterogeneous catalyst

Enantiomeric Separation of Four Chiral Compounds Using Immobilized Cellulose 3, 5-Dimethylphenylcarbamate as Chiral Stationary Phase

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Chinese Chemical Letters 2006年第9期17卷 1213-1216页

作者： yong Fei minG Liang ZHAO Hong Li ZHANG Yan Ping shi yong min LI Li Ren CHEN Key Laboratory for Natural Medicine of Gansu Province Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 The Graduate School of Chinese Academy of Sciences Beijing 100039

A new chiral stationary phase of 3, 5-dimethylphenylcarbamates of cellulose, chemically bonded to 3-aminopropylsilica gel at the 6-positions of the glucose units, was prepared. The solvent versatility of the CSP was investigated for the enantioselective separation of four pairs of enantiomers using THF and chloroform as non-standard mobile phase eluent in HPLC. The influence of temperature on the resolution was investigated.

关键词： HPLC immobilized enantiomeric separation.

Asymmetric Reactions Catalyzed by Chiral Tertiary Phosphines

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Chinese Journal of Chemistry 2020年第11期38卷 1395-1421页

作者： Yin Wei min shi State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisUniversity of Chinese Academy of SciencesShanghai Institute of Organic ChemistryChinese Academy of Sciences345 Ling ling RoadShanghai 200032China

Chiral tertiary phosphines are versatile Lewis base catalysts capable of promoting a wide range of asymmetric *** particular,the recent designed chiral phosphines based on the concept of bi-/multifunctionality have been demonstrated to be effective catalysts for many types of asymmetric reactions such as(aza)-MBH reaction/RC reaction,cycloaddition reaction,domino reaction,nucleophilic addition reaction,*** review summarizes the recent advances in this field and highlights the selected significant achievements.

关键词： Chiral asymmetric versatile

An improvement of Chen-Ru-Yan's degenerated second main theorem

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Science China Mathematics 2015年第12期58卷 2517-2530页

作者： shi Lei RU min Department of Mathematics East China Normal University Department of Mathematics University of Houston

We give an improvement for the second main theorem of algebraically non-degenerate holomorphic curves into a complex projective variety V intersecting hypersurfaces in subgeneral position, obtained by Chen et al.(2012... 详细信息

关键词： Nevanlinna theory holomorphic curve second main theorem truncation level