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Chinese Journal of Mechanical Engineering 2024年第4期37卷 290-305页

作者： chao wang Tao Zhu Bing Yang Shoune Xiao Guangwu Yang State Key Laboratory of Rail Transit Vehicle System Southwest Jiao tong UniversityChengdu 610031China

The current research on the integrity of critical structures of rail vehicles mainly focuses on the design stage,which needs an effective method for assessing the service *** paper proposes a framework for predicting the remaining useful life(RUL)of in-service structures with and without visible *** hypothetical distribution and delay time models were used to apply the equivalent crack growth life data of heavy-duty railway cast steel knuckles,which revealed the evolution characteristics of the crack length and life scores of the knuckle under different fracture failure *** results indicate that the method effectively predicts the RUL of service knuckles in different failure modes based on the cumulative failure probability curves for different locations and surface crack *** study proposes an RUL prediction framework that supports the dynamic overhaul and state maintenance of knuckle fatigue cracks.

关键词： Heavy-duty railway Cast steel knuckle Remaining useful life Fatigue crack growth Hypothetical distribution

Enantioselective Alkylation of Aldehydes with Organoborons Enabled by Nickel/N-Heterocyclic Carbene Catalysis

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Chinese Journal of Chemistry 2024年第18期42卷 2161-2165页

作者： Song-Yang Liu Zi-chao wang Shi-Liang Shi College of Chemistry and Material Science Shanghai Normal University100 Guilin RoadShanghai 200234China State Key Laboratory of Organometallic Chemistry Shanghai Institute of rganic ChemitryUniversity of Chinee Academy of Scienc Chinese Academy of Sciences345 Lingling RoadShanghai 200032China

Transition-metal-catalyzed asymmetric alkylation of aldehydes represents a straightforward strategy for the synthesis of chiral secondary ***,efficient methods using organoborons as coupling reagents are ***,we report a highly enantioselective nickel-catalyzed alkylation reaction of aldehydes,using readily available alkylborons as nucleophiles.A wide variety of chiral secondary alcohols were prepared from commercially available aldehydes with high *** key to the excellent enantioselectivity and chemoselectivity was the employment of a bulky C2-symmetric chiral NHC *** protocol features excellent enantiocontrol,mild conditions,and good functional group compatibility.

关键词： Enantioselective alkylation Nickel catalysis N-Heterocyclic carbene Organoborons Chiral alcohols Asymmetric catalysis C-C coupling Synthetic methods

An Immune-Inspired Approach with Interval Allocation in Solving Multimodal Multi-Objective Optimization Problems with Local Pareto Sets

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Computers, Materials & Continua 2024年第6期79卷 4237-4257页

作者： Weiwei Zhang Jiaqiang Li chao wang Meng Li Zhi Rao College of Computer Science and Technology Zhengzhou University of Light IndustryZhengzhou450001China Technology Research and Development Center Jilin Tobacco Industry Company LimitedChangchun130031China College of Tobacco Science and Engineering Zhengzhou University of Light IndustryZhengzhou450001China Raw Material Department Hongyun Honghe Tobacco(Group)CompanyKunming650202China

In practical engineering,multi-objective optimization often encounters situations where multiple Pareto sets(PS)in the decision space correspond to the same Pareto front(PF)in the objective space,known as Multi-Modal Multi-Objective Optimization Problems(MMOP).Locating multiple equivalent global PSs poses a significant challenge in real-world applications,especially considering the existence of local *** identifying and locating both global and local PSs is a major *** tackle this issue,we introduce an immune-inspired reproduction strategy designed to produce more offspring in less crowded,promising regions and regulate the number of offspring in areas that have been thoroughly *** approach achieves a balanced trade-off between exploration and ***,we present an interval allocation strategy that adaptively assigns fitness levels to each *** strategy ensures a broader survival margin for solutions in their initial stages and progressively amplifies the differences in individual fitness values as the population matures,thus fostering better population ***,we incorporate a multi-population mechanism that precisely manages each subpopulation through the interval allocation strategy,ensuring the preservation of both global and local *** results on 21 test problems,encompassing both global and local PSs,are compared with eight state-of-the-art multimodal multi-objective optimization *** results demonstrate the effectiveness of our proposed algorithm in simultaneously identifying global Pareto sets and locally high-quality PSs.

关键词： Multimodal multi-objective optimization problem local PSs immune-inspired reproduction

A new fluorocarbon adhesive:Inhibiting agglomeration during combustion of propellant via efficient F-Al_(2)O_(3) preignition reaction

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Carbon Energy 2024年第6期6卷 292-305页

作者： Qifa Yao Min Xia chao wang Fanzhi Yang Wei Yang Yunjun Luo School of Materials Science and Engineering Beijing Institute of TechnologyBeijingChina Key Laboratory of High Energy Density Materials Ministry of EducationBeijing Institute of TechnologyBeijingChina School of Aerospace Engineering Beijing Institute of TechnologyBeijingChina Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijingChina

Inhibiting the agglomeration of molten aluminum particles packed in the binder network is a promising scheme to achieve efficient combustion of solid *** this investigation,the hydroxyl-terminated structured fluorinated alcohol compound(PFD)was introduced to modify the traditional polyethylene glycol/polytetrahydrofuran block copolymerization(HTPE)binder;that is,a unique fluorinated polyether(FTPE)binder was synthesized by embedding fluorinated organic segments into the HTPE binder via crosslinking *** FTPE was applied in aluminum-based propellants for the first *** to the complete release of fluorinated organic active segments in the range of 300℃to 400℃,the burning rate of FTPEbased propellant increased from 4.07(0%PFD)to 6.36 mm/s(5%PFD),increased by 56.27%under 1 *** reaction heat of FTPE propellants increased from 5.95(0%PFD)to 7.18 MJ/kg(5%PFD)under 3.0 MPa,indicating that HTPE binder modified with PFD would be conducive to inhibiting the D90 of condensed combustion products(CCPs)dropped by 81.84%from 75.46(0%PFD)to 13.71μm(5%PFD)under 3.0 MPa,in consistent with the significant reduction of aluminum agglomerates observed on the quenched burning surface of the *** results demonstrated that a novel FTPE binder with PFD can release fluorinated organic active segments,which motivate preignition reaction with the alumina shell in the early stage of aluminum combustion,and then enhance the melting diffusion effect of aluminum to inhibit the agglomeration.

关键词： agglomeration characteristics aluminum particles combustion fluorine alcohol compounds HTPE propellants

A widely targeted metabolite modificomics strategy for modified metabolites identification in tomato

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Journal of Integrative Plant Biology 2024年第4期66卷 810-823页

作者： Jun Yang Ridong Chen chao wang Chun Li Weizhen Ye Zhonghui Zhang Shouchuang wang School of Breeding and Multiplication(Sanya Institute of Breeding and Multiplication) Hainan UniversitySanya 572025China School of Tropical Agriculture and Forestry Hainan UniversityHaikou 572208China

The structural and functional diversity of plant metabolites is largely created via chemical modification of a basic ***,metabolite modifications in plants have still not been thoroughly investigated by metabolomics *** this study,a widely targeted metabolite modificomics(WTMM)strategy was developed based on ultra-high performance liquid chromatography-quadrupole-linear ion trap(UHPLC-Q-Trap)and UHPLC-Q-Exactive-Orbitrap(UHPLC-QE-Orbitrap),which greatly improved the detection sensitivity and the efficiency of identification of modified metabolites.A metabolite modificomics study was carried out using tomato as a model,and over 34,000 signals with MS2 information were obtained from approximately 232 neutral loss *** metabolite profiling was also performed by utilizing high-resolution mass spectrometry data to annotate a total of 2,118 metabolites with 125 modification types;of these,165 modified metabolites were identified in this ***,the WTMM database was used to assess diseased tomato tissues and 29 biomarkers were *** summary,the WTMM strategy is not only capable of large-scale detection and quantitative analysis of plant-modified metabolites in plants,but also can be used for plant biomarker development.

关键词： LC-MS metabolic diversity metabolite modificomics modified groups tomato

Network analysis reveals context-dependent structural complexity of social calls in serrate-legged small treefrogs

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Current Zoology 2024年第2期70卷 253-261页

作者： Ke Deng Qiao-Ling He Tong-Liang wang Ji-chao wang Jian-Guo Cui CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China University of Chinese Academy of Science Beijing 100049China Ministry of Education Key Laboratory for Ecology of Tropical lslands Key Laboratory of Tropical Animal and Plant Ecology of Hainan ProvinceCollege of Life SciencesHainan Normal UniversityHaikou 571158China

Vocal communication plays an important role in survival,reproduction,and animal social *** and mammals produce com-plex vocal sequence to convey context-dependent *** are conspicuous features of the behavior of most anuran species(frogs and toads),and males usually alter their calling strategies according to ecological context to improve the attractiveness/***,very few studies have focused on the variation of vocal sequence in *** the present study,we used both conventional method and network analysis to investigate the context-dependent vocal repertoire,vocal sequence,and call network structure in serrate-legged small treefrogs Kurixalus *** found that male *** modified their vocal sequence by switching to different call types and increasing repertoire size in the presence of a competitive ***,compared with before and after the playback of advertisement calls,males emited fewer advertisement calls,but more aggressive calls,encounter calls,and compound calls during the playback *** analysis revealed that the mean degree,mean closeness,and mean betweenness of the call networks significantly decreased during the playback period,which resulted in lower *** addition,the increased proportion of one-way motifs and average path length also indicated that the connectivity of the call network decreased in competitive ***,the vocal sequence of *** did not display a clear small-world network structure,regardless of *** study presents a paradigm to apply network analysis to vocal sequence in anurans and has important implications for understanding the evolution and function of sequence patterns.

关键词： call network centrality Kurixalus odontotarsus vocal repertoire vocal sequence.

Pathogenic Surveillance of Foodborne Illness-Related Diarrhea—Beijing Municipality,China,2013-2023

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China CDC weekly 2024年第24期6卷 568-573页

作者： chao wang Tongyu wang Yanlin Niu Yangbo Wu Jinru Jiang Xiaochen Ma Institute for Nutrition and Food Hygiene Beijing Center for Disease Prevention and ControlBeijingChina

What is already known about this topic?Foodborne diseases present a significant public health concern,particularly in China,where they represent a significant food safety ***,there is a need for a thorough and systematic analysis of the extended epidemiological patterns of foodborne diseases in Beijing *** is added by this report?Monitoring results show that Norovirus and diarrheagenic Escherichia coli(DEC)are the most commonly identified foodborne diarrheal *** aged 19–30 are at a higher risk of foodborne diarrhea in Beijing,with Salmonella infection being associated with fever *** are the implications for public health practice?This study analyzes 11 years of consecutive monitoring data to enhance understanding of the epidemiological and clinical features of foodborne diarrhea in *** aims to identify high-risk populations,assist in clinical pathogen identification and treatment,and support the development of tailored preventive strategies.

关键词： Beijing safety borne

Highly selectiveα-C(sp^(3))-H arylation of alkenyl amides via nickel chain-walking catalysis

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Chinese Chemical Letters 2024年第7期35卷 271-275页

作者： Haoran Shi Jiaxin wang Yuqin Zhu Hongyang Li Guodong Ju Lanlan Zhang chao wang Tianjin Key Laboratory of Structure and Performance for Functional Molecules College of ChemistryTianjin Normal UniversityTianjin 300387China

Herein,we report the migratory hydroarylation of unactivated alkenes with aryl iodides using native and weakly coordinating amide directors under mild *** coordination of the monodentate directing group and the ligand enable the highly regioselective migratory hydroarylation via a chain walking process to form the thermodynamically stable five-membered nickelacyle *** protocol provides a variety of valuableα-aryl-substituted alkylamine products,and exhibited good functional group *** modification of bioactive compounds such as fenofibrate and indomethacin further highlights the synthetic value of this protocol.

关键词： Alkenes Hydroarylation Chain-walking Regioselective Nickel catalysis

Micro-aluminum powder with bi-or tri-component alloy coating as a promising catalyst:Boosting pyrolysis and combustion of ammonium perchlorate

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Defence Technology（防务技术） 2024年第3期33卷 100-113页

作者： chao wang Ying Liu Mingze Wu Jia Li Ying Feng Xianjin Ning Hong Li Ningfei wang Baolu Shi School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

A novel design of micro-aluminum(μAl)powder coated with bi-/tri-component alloy layer,such as:Ni-P and Ni-P-Cu(namely,Al@Ni-P,Al@Ni-P-Cu,respectively),as combustion catalysts,were introduced to release its huge energy inside Al-core and promote rapid pyrolysis of ammonium perchlorate(AP)at a lower temperature in aluminized *** microstructure of Al@Ni-P-Cu demonstrates that a three-layer Ni-P-Cu shell,with the thickness of~100 nm,is uniformly supported byμAl carrier(fuel unit),which has an amorphous surface with a thickness of~2.3 nm(catalytic unit).The peak temperature of AP with the addition of Al@Ni-P-Cu(3.5%)could significantly drop to 316.2℃ at high-temperature thermal decomposition,reduced by 124.3℃,in comparison to that of pure AP with 440.5℃.It illustrated that the introduction of Al@Ni-P-Cu could weaken or even eliminate the obstacle of AP pyrolysis due to its reduction of activation energy with 118.28 kJ/*** laser ignition results showed that the ignition delay time of Al@Ni-P-Cu/AP mixture with 78 ms in air is shorter than that of Al@Ni-P/AP(118 ms),decreased by 33.90%.Those astonishing breakthroughs were attributed to the synergistic effects of adequate active sites on amorphous surface and oxidation exothermic reactions(7597.7 J/g)of Al@Ni-P-Cu,resulting in accelerated mass and/or heat transfer rate to catalyze AP pyrolysis and ***,it is believed to provide an alternative Al-based combustion catalyst for propellant designer,to promote the development the propellants toward a higher energy.

关键词： Micro-aluminum powder(μAl) Nano-sized alloy coating Combustion catalyst Ammonium perchlorate Pyrolysis behavior Ignition and combustion

Wellbore-heat-transfer-model-based optimization and control for cooling downhole drilling fluid

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Petroleum Science 2024年第3期21卷 1955-1968页

作者： chao wang He Liu Guo-Wei Yu Chen Yu Xian-Ming Liu Peng Huang Yangtze University Jingzhou434023HubeiChina State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing2249China CNPC Bohai Drilling Engineering Co. LtdTianjin300280China Exploration Development and Construction Engineering Division of PetroChina Jidong Oilfield Company Tangshan63200HebeiChin Henan University of Urban Construction Pingdingshan467036HenanChina

To address the two critical issues of evaluating the necessity of implementing cooling techniques and achieving real-time temperature control of drilling fluids underground in the current drilling fluid cooling technology,we first established a temperature and pressure coupled downhole heat transfer model,which can be used in both water-based and oil-based drilling ***,fourteen factors,which could affect wellbore temperature,were *** on the standard deviation of the downhole temperature corresponding to each influencing factor,the influence of each factor was *** influencing factors that can be used to guide the drilling fluid's cooling technology were drilling fluid thermal conductivity,drilling fluid heat capacity,drilling fluid density,drill strings rotation speed,pump rate,viscosity,ROP,and injection *** nondominated sorting genetic algorithm was used to optimize these six parameters,but the optimization process took 182 *** these eight parameters'influence rules with the nondominated sorting genetic algorithm can reduce the optimization time to 108 ***,the downhole temperature has been demonstrated to increase with the inlet temperature increasing linearly under quasi-steady *** this law and PID,the downhole temperature can be controlled,which can reduce the energy for cooling the surface drilling fluid and can ensure the downhole temperature reaches the set value as soon as possible.

关键词： Drilling Cooling Influencing factors Analysis Optimization Control