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Journal of Environmental Sciences 2024年第6期140卷 157-164页

作者： Xiaofeng Cui Xueting wang Lijun Zhao jixin wang Tingting Kong Yujie Xiong Anhui Engineering Research Center of Carbon Neutrality The Key Laboratory of Functional Molecular SolidsMinistry of EducationAnhui Laboratory of Molecular-Based MaterialsCollege of Chemistry and Materials ScienceAnhui Normal UniversityWuhu 241002China School of Chemistry and Chemical Engineering Anqing Normal UniversityAnqing 246011China School of Chemistry and Materials Science University of Science and Technology of ChinaHefei 230026China

Homogenous molecular photocatalysts for CO_(2)reduction,especially metal complex-based photosensitizer-catalyst assemblages,have been attracting extensive research interests due to their efficiency and ***,their low durability and recyclability limit practical *** this work,we immobilized the catalysts of metal terpyridyl complexes and the photosensitizer of[Ru(bpy)3]Cl2onto the surface of carbon nanotubes through covalent bonds and electrostatic interactions,respectively,transforming the homogeneous system into a heterogeneous *** characterizations prove that these metal complexes are well dispersed on CNTs with a high loading(ca.12 wt.%).Photocatalytic measurements reveal that catalytic activity is remarkably enhanced when the molecular catalysts are anchored,which is three times higher than that of homogeneous molecular ***,when the photosensitizer of[Ru(bpy)3]Cl2is immobilized,the side reaction of hydrogen evolution is completely suppressed and the selectivity for CO production reaches 100%,with its durability also significantly *** work provides an effective pathway for constructing heterogeneous photocatalysts based on rational assembly of efficient molecular photosensitizers and catalysts.

关键词： durability selectivity catalyst

Establishment Method of a Mixture Model and Its Practical Application for Transmission Gears in an Engineering Vehicle

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Chinese Journal of Mechanical Engineering 2012年第5期25卷 1001-1010页

作者： wang jixin wang Zhenyu YU Xiangjun YAO Mingyao YAO Zongwei ZHANG Erping College ofMechanicalScience andEngineering Jilin University Changchun 130022 China School of Automatic Control and Mechanical Engineering Kunming University Kunming 650214 China Guangxi Liugong Machinery Co. Ltd. Liuzhou 545007 China

Highly versatile machines, such as wheel loaders, forklifts, and mining haulers, are subject to many kinds of working conditions, as well as indefinite factors that lead to the complexity of the load. The load probability distribution function （PDF） of transmission gears has many distributions centers; thus, its PDF cannot be well represented by just a single-peak function. For the purpose of representing the distribution characteristics of the complicated phenomenon accurately, this paper proposes a novel method to establish a mixture model. Based on linear regression models and correlation coefficients, the proposed method can be used to automatically select the best-fitting function in the mixture model. Coefficient of determination, the mean square error, and the maximum deviation are chosen and then used as judging criteria to describe the fitting precision between the theoretical distribution and the corresponding histogram of the available load data. The applicability of this modeling method is illustrated by the field testing data of a wheel loader. Meanwhile, the load spectra based on the mixture model are compiled. The comparison results show that the mixture model is more suitable for the description of the load-distribution characteristics. The proposed research improves the flexibility and intelligence of modeling, reduces the statistical error and enhances the fitting accuracy, and the load spectra complied by this method can better reflect the actual load characteristic of the gear component.

关键词： mixture distribution model probability distribution function correlation coefficient load spectra wheel loader

A method for threshold selection in load extrapolation based on multiple criteria decision-making technology

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International Journal of Modeling, Simulation, and Scientific Computing 2017年第3期8卷 21-38页

作者： jixin wang Qingsong Liu Xinting Zhai School of Mechanical Science and Engineering Jilin University No.5988 Renmin Street ChangchunJilin 130022Renmin Street Nanguan DistrictP.R.China

In order to establish an accurate peak over threshold(POT)model for reasonable load extrapolation,a new threshold selection method based on multiple criteria decision making(MCDM)technology is *** fitting test criterion is taken into consideration in the *** each candidate threshold,the fitting values of several fitting test criteria are integrated into a comprehensive evaluation value through entropy method and MCDM *** threshold corresponding to the minimum comprehensive evaluation value is assumed as the optimal threshold.A random simulation study is carried out to evaluate the performance of the method and to compare them with other literature *** load data are applied the proposed *** the results shown that the proposed method could be seen as an additional method that complements existing threshold selection methods.

关键词： Load extrapolation threshold selection fitting test criteria multiple criteria decision-making technology comprehensive evaluation value

Optimization of Animal-Glue Binders for Casting Applications

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Fluid Dynamics & Materials Processing 2023年第11期19卷 2923-2932页

作者： Tianshu wang Guoqing Sun Shaojun Zhang Mingyu wang jixin wang Yunwu Han Mechanical and Electronic Engineering Shandong Jiaotong UniversityJinan250357China Chongqing Research Institute Jilin UniversityChongqing401123China School of Intelligent Transportation Jiangsu Vocational College of Electronics and InformationHuai’an223003China

In typical metal foundry applications,sand casting is still the most used *** related binder plays a very important role as its performances can directly influence the quality of *** many binders,glues of animal origin have attracted much attention in recent years due to their reduced environmental ***-ever,they display some drawbacks such as the tendency to coagulate easily at room temperature and a relatively low *** this study,a novel gas-hardening casting binder was prepared using an animal glue and anhy-drous potassium carbonate as a hydrolyzing agent to avoid undesired ***,sodium pyropho-sphate and furfuryl alcohol were exploited as modifiers to obtain a binder with a high compressive *** best modification conditions,determined by means of an orthogonal design matrix approach,were 4 g of Na2CO3,sodium pyrophosphate,furfuryl alcohol and animal glue with a ratio of 4:12:100,at 85°C and with a duration of 115 min,*** viscosity of the mixture obtained under these optimized conditions was 1250 mPa⋅*** compressive strength of the binder,hardened by CO_(2) gas,was 4.00 *** gas evolution at 850°C was 15 ml⋅g-1,and its residual strength after 10 min calculation at 800°C was 0.01 MPa,which is high enough to meet the requirement of core-making in ***,after hydrolysis and further modification,animal glue and modifiers displayed a grafting reaction and an esterification reaction,respectively,which made the adhesive network denser and improved its thermal stability.

关键词： Animal glue binder phosphate CO_(2)gas casting sand

S-,P-stabilized bromoallenes for modular allenylborylation of alkenes

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Science China Chemistry 2024年第1期67卷 360-367页

作者： jixin wang Donghao Luo Ying Hu Zhili Duan Jianlin Yao Konstantin Karaghiosoff Jie Li Key Laboratory of Organic Synthesis of Jiangsu Province Suzhou Key Laboratory of Pathogen Bioscience and Anti-infective MedicineCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China Department Chemie Ludwig-Maximilians-Universitat MunchenButenandtstr.5-13Haus F81377 MunichGermany State Key Laboratory and Institute of Elemento-Organic Chemistry Haihe Laboratory of Sustainable Chemical TransformationsCollege of ChemistryNankai UniversityTianjin 300071China

Simultaneously forming a carbon-carbon and a carbon-heteroatom bond in a single step through transition metal-catalyzed alkene difunctionalization strategy has emerged as a powerful tool for synthetic organic *** to the uncontrollable reactivity,direct cross-coupling with bromoallenes as the building blocks for the selective allenation and borylation remains *** herein report a new type of S-and P-stabilized bromoallenes for palladium-catalyzed modular allenation and borylation of alkenes to the divergent synthesis of multiply functionalized allenes in a highly regio-and diastereoselective *** reaction features broad substrate scope and wide functional group compatibility,thus providing a straightforward method to install allenyl and boryl groups across *** experiments highlight the crucial importance of S-,P-stabilization for the oxidative insertion of Pd-species into the allenyl-Br *** facile syntheses of bioactive allenic steroids and exocyclic allenes demonstrate the synthetic utility of this protocol.

关键词： alkene difunctionalization olefins bromoallenes allenylborylation palladium

Load analyzing of nonstationary load history of engineering vehicles by switching Markov chain

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International Journal of Modeling, Simulation, and Scientific Computing 2018年第6期9卷 171-187页

作者： Yuqian Wu Shuang You Yi Li Yunlong Liang jixin wang School of Mechanical Science and Engineering Jilin University Changchun 130025P.R.China Faw Technology Center Changchun 130025P.R.China School of Mechanical Science and Engineering Jilin University No.5988 People’s Street ChangchunJilin 130022/Nanguan DistrictP.R.China Shanghai Volkswagen Automotive Co Ltd Yangzhou 225000 P.R.China

Engineering vehicles are widely used under various harsh working *** many components in them,service loadings they suffered are usually random and nonstationary due to their remarkable characteristic called cyclic *** deal with that,section method can be ***,this method will neglect those transition cycles caused by switching load section,which can contribute a lot to *** order to consider those transition cycles,this paper applied the model called“Switching Markov Chain of Turning Points”(SMCTP).Then the expected rain-flow matrix is compared with the overall rain-flow matrix conducted by section *** comparison result shows that SMCTP can perform well in processing nonstationary *** a result,the Switching Markov Chain method(SMC)was proved to be effective in stochastically characterizing the nonstationary switching loadings of engineering vehicles.

关键词： Engineering vehicle nonstationary switching loadings switching Markov chain MCMC section method.

Opportunities and Challenges in the Social Development of Latin America

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International Understanding 2007年第3期 12-15页

作者： Liu jixin wang Wei

Entering the threshold of the 21st century, Latin American countries, in active response tothe callsof the UN Millennium Summit, have been striving

关键词：机会挑战社会发展美国拉丁文

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乌鲁木齐河灌区水资源利用及可持续管理

干旱区地理 1999年第4期22卷 22-28页

作者：王吉新乌鲁木齐河管理处乌鲁木齐830049

通过对乌鲁木齐河灌区历年供水和用水状况分析，提出了该灌区水资源可持续利用的对策，并针对城市用水逐年增加与水资源供需矛盾日益突出的形势，从水价分析入手，从水资源可持续管理的角度，提出了水资源高效利用与管理的对策。

关键词：乌鲁木齐河灌区水资源利用可持续管理水资源

Automatic determination method of optimal threshold based on the bootstrapping technology

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Journal of Southeast University(English Edition) 2018年第2期34卷 208-212页

作者： wang jixin wang Yan Zhai Xinting Huang Yajun wang Zhenyu School of Mechanical Science and Engineering Jilin UniversityChangchun 130025China Shantui Construction Machinery Co. Ltd.Jining 272073China

In order to predict the extreme load of the mechanical components during the entire life,an automatic method based on the bootstrapping technology(BT)is proposed to determine the most suitable *** on all the turning points of the load history and a series of thresholds estimated in advance,the generalized Pareto distribution is established to fit the *** corresponding distribution parameters are estimated with the maximum likelihood ***,BT is employed to calculate the mean squared error(MSE)of each estimated threshold based on the exceedances and the specific distribution ***,the threshold with the smallest MSE will be the optimal *** to the kurtosis method and the mean excess function method,the average deviation of the probability density function of exceedances determined by BT reduces by 38.52%and 29.25%,***,the quantile-quantile plot of the exceedances determined by BT is closer to a straight *** results suggest the improvement of the modeling flexibility and the determined threshold *** the exceedances are insufficient,BT will enlarge their amount by resampling to solve the instability problem of the original distribution parameters.

关键词： load spectrum peak over threshold threshold selection bootstrapping technology mean squared error

Exploring Antarctic subglacial lakes with RECoverable Autonomous Sonde(RECAS):Design and first field tests

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Science China(Technological Sciences) 2024年第6期67卷 1866-1878页

作者： SUN YouHong PAVEL Talalay LI YuanSheng YU HaiBin wang DongLiang LI GuoPing XU LiPing GONG Da wang jixin wang JianHua wang Ting ZHANG Nan wang ZhiGang CHEN YanJi LIU YunChen LI YaZhou PENG ShiLin SHI JianGuang AN ChunLei GE Qun XU Jing NI XiaoKang CUI QiFeng JIANG Qiang MIKHAIL Sysoev Yang Yang wang RuSheng WEI XianZhe wang Yu ZHU TianXin DENG ZhiPeng ALEXEY Markov LI Bing FAN XiaoPeng Polar Research Center Jilin UniversityChangchun130000China School of Engineering and Technology China University of GeosciencesBeijing100083China Polar Research Institute of China Shanghai200120China College of Electronics and Information Hangzhou Dianzi UniversityHangzhou310018China Aerospace System Engineering Shanghai Shanghai201109China Nanjing Institute of Astronomical Optics&Technology National Astronomical ObservatoriesChinese Academy of SciencesNanjing210000China National Ocean Technology Center Tianjin300000China

Conducting scientific drilling on subglacial lakes and obtaining samples of subglacial lake water holds great significance in unraveling the formation and evolution of Antarctic subglacial lakes and early Earth's life *** various approaches to access and directly sample subglacial water and sediments,clean access and exploration of subglacial lakes remain *** address this concern,Jilin University has developed the RECoverable Autonomous Sonde(RECAS)*** technology enables sampling and in-situ detection of subglacial lake water while being isolated from the surface,thus minimizing the risk of *** tests,including downward and upward drilling,long-running,remote-control,and cold-environment assessments,were conducted to validate the sonde's principle and *** the 38th Chinese National Antarctic Research Expedition,CHINARE(2021–2022 season),the RECAS prototype underwent testing on the flank region of Dalk glacier,10 km from Zhongshan Station in *** boreholes with depths of 200.3,183.2,and 133.5 m were successfully drilled,with the refrozen meltwater sealing the boreholes during the *** 600 mL of melted water samples were collected from each *** the drilling tests,all systems of the RECAS prototype performed within the expected ranges.

关键词： subglacial lake thermal drilling water sampling Antarctic autonomous sonde