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Contact Stress Reliability Analysis Model for Cylindrical Gear with Circular Arc Tooth Trace Based on an Improved Metamodel

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 593-619页

作者： Qi Zhang Zhixin Chen Yang Wu Guoqi Xiang Guang wen Xuegang Zhang Yongchun xie Guangchun Yang School of Intelligent Manufacturing&Automobile Chengdu Industrial Vocational Technical CollegeChengdu610218China School of Intelligent Manufacturing Panzhihua UniversityPanzhihua617000China School of Electrical Engineering Chengdu Industry and Trade CollegeChengdu601165China School of Mechanical Engineering Sichuan UniversityChengdu601165China Chengdu Technological University Chengdu611730China

Although there is currently no unified standard theoretical formula for calculating the contact stress of cylindrical gears with a circular arc tooth trace(referred to as CATT gear),a mathematical model for determining the contact stress of CATT gear is essential for studying how parameters affect its contact stress and building the contact stress limit state equation for contact stress reliability *** this study,a mathematical relationship between design parameters and contact stress is formulated using the *** enhance the model’s accuracy,we propose a new hybrid algorithm that merges the genetic algorithm with the Quantum Particle Swarm optimization algorithm,leveraging the strengths of ***,the“parental inheritance+self-learning”optimization model is used to fine-tune the KrigingMetamodel’s *** this,amathematicalmodel for calculating the contact stress of Variable Hyperbolic Circular-Arc-Tooth-Trace(VH-CATT)gears using the optimized Kriging model was *** then examined how different gear parameters affect the VH-CATT gears’contact *** simulation results show:(1)Improvements in R2,RMSE,and RMAE.R2 rose from0.9852 to 0.9974(a 1.22%increase),nearing 1,suggesting the optimized Kriging Metamodel’s global error is ***,RMSE dropped from3.9210 to 1.6492,a decline of 57.94%.The global error of the GA-IQPSO-Kriging algorithm was also reduced,with RMAE decreasing by 58.69%from 0.1823 to 0.0753,showing the algorithm’s enhanced *** a comparison of ten experimental groups selected randomly,the GA-IQPSO-Kriging and FEM-based contact analysis methods were used to measure contact *** revealed a maximum error of 12.11667 MPA,which represents 2.85%of the real value.(2)Several factors,including the pressure angle,tooth width,modulus,and tooth line radius,are inversely related to contact *** descending order of their impact on the contact stress is:tooth line radius>modulus

关键词： CATT gear contact stress finite element method metamodel hybrid algorithm influencing factors

Enhancing Tea Leaf Disease Identification with Lightweight MobileNetV2

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Computers, Materials & Continua 2024年第7期80卷 679-694页

作者： Zhilin Li Yuxin Li Chunyu Yan Peng Yan Xiutong Li Mei Yu Tingchi wen Benliang xie College of Big Data and Information Engineering Guizhou UniversityGuiyang550025China Power Semiconductor Device Reliability Engineering Center of the Ministry of Education Guiyang550025China State Key Laboratory of Public Big Data Guizhou UniversityGuiyang550025China The Mushroom Research Centre Guizhou UniversityGuiyang550025China The Engineering Research Center of Southwest Bio-Pharmaceutical Resources Ministry of EducationGuizhou UniversityGuiyang550025China

Diseases in tea trees can result in significant losses in both the quality and quantity of tea *** monitoring can help to prevent the occurrence of large-scale diseases in tea ***,existingmethods face challenges such as a high number of parameters and low recognition accuracy,which hinders their application in tea plantation monitoring *** paper presents a lightweight I-MobileNetV2 model for identifying diseases in tea leaves,to address these *** proposed method first embeds a Coordinate Attention(CA)module into the originalMobileNetV2 network,enabling the model to locate disease regions ***,a Multi-branch Parallel Convolution(MPC)module is employed to extract disease features across multiple scales,improving themodel’s adaptability to different disease ***,the AutoML for Model Compression(AMC)is used to compress themodel and reduce computational *** results indicate that our proposed algorithm attains an average accuracy of 96.12%on our self-built tea leaf disease dataset,surpassing the original MobileNetV2 by 1.91%.Furthermore,the number of model parameters have been reduced by 40%,making itmore suitable for practical application in tea plantation environments.

关键词： Disease identification coordinate attention mechanism multi-scale feature extraction model pruning

Sandpaper-templated Stretchable Immunosensing Electrodes for Sub-picomolar Progesterone Detection

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Chemical Research in Chinese Universities 2024年第5期40卷 874-880页

作者： LI Zhaoxian MENG Xingyu FANG Chuyao YI Zhenkai WU Yaoyao LIU Xuanxuan zhong Wei ZHANG Limei xie Zhuang School of Materials Science and Engineering Key Laboratory for Polymeric Composite and Functional Materials of Ministry of EducationSun Yat-sen UniversityGuangzhou510275P.R.China Reproductive Medicine Center Department of Obstetrics and Gynecologythe First Affiliated Hospital of Sun Yat-sen UniversityGuangzhou510080P.R.China

Female hormone detection,particularly non-invasive monitoring progesterone(P4)levels in body fluids,plays a critical role in female health management and disease ***,the challenge still exists because of the ultralow abundance of P4(<100 pmol/L)in sweat and saliva,necessitating highly sensitive methods for wearable ***,we present a simple sandpaper-templated stretchable immunosensing electrode designed for ultra-sensitive detection of P4 at sub-picomolar level.A molding technique is employed to replicate the sandpaper textures to provide a microstructured elastomeric substrate for electrode *** microstructured surface coated with poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate)(PEDOT:PSS)/LiTFSI[LiTFSI=lithium bis(trifluoromethanesulfonyl)imide]provided a stretchable polymer electrode with high conductivity,and further decoration with gold nanoparticles(AuNPs)enabled the immunosensing for P4 by electrochemical impedance spectroscopy(EIS)*** adjusting the AuNPs deposition conditions,ultrasensitive detection of P4 is realized with a low limit of detection(LOD)of ca.10 fmol/L and a tunable dynamic range up toµmol/***,the stretchable electrode exhibits stable electrochemical performance,enabling the detection of P4 at sub-picomolar levels even under mechanical strain of 30%.This innovative electrochemical sensor holds significant promise for non-invasive,on-site monitoring of P4 levels in healthcare,as well as hormone detection in food safety and environment surveillance.

关键词： Progesterone Immunosensor Microstructured electrode Stretchable biosensor Electrochemical sensing

Several whitefly genome assemblies and an integrated whitefly gene search platform

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Insect Science 2024年第1期31卷 299-306页

作者： Xingnuo Li Peng Liang Mingyue Wu Shaoli Wang Qingjun Wu wen xie Youjun Zhang State Key Laboratory of Vegetable Biobreeding Institute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijingChina Sanya Academy of Troprical Agricultural Sciense SanyaHainanChina National Research Institute of Breeding in Hainan Chinese Academy of Agricultural SciencesSanyaHainanChina

Dear Editor,The characteristics and importance of the whitefly Bemisia tabaci as an economic pest seem to continually get more and more *** the whiteflies *** including,at least 11 genetic groups and 36 morphologically indistinguishable cryptic species,invasive MEAMl(Middle East-Asia Minor 1,"B"type)and MED(the Mediterranean,"Q"type)are the 2 most destructive cryptic species of the B.

关键词： Middle white East

Thioredoxin pathway regulated live-cell synthesis of CdSe quantum dots in Saccharomyces cerevisiae

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Science China Chemistry 2024年第11期67卷 3851-3860页

作者： Xu Li Cai-Qin Wu Jia-Wei Tu Juan Kong Ling-Ling Yang Zhi-Xiong xie Dai-wen Pang College of Chemistry and Molecular Sciences The Institute for Advanced Studies College of Life Sciences Wuhan University Research Center for Analytical Sciences College of Chemistry State Key Laboratory of Medicinal Chemical Biology Tianjin Key Laboratory of Biosensing and Molecular Recognition Frontiers Science Center for New Organic Matter Frontiers Science Center for Cell Responses and Haihe Laboratory of Sustainable Chemical Transformations Nankai University

Currently, the application of synthetic biology to artificially manipulate and utilize organisms for the synthesis of desired products such as nanomaterials with excellent fluorescence properties is attracting considerable attention. However, it is still difficult to obtain designed products efficiently due to insufficient knowledge of the biosynthetic mechanisms. The thioredoxin（TRX） and glutathione（GSH） pathways are generally conserved thiol-reductase systems that protect organisms from oxidative stress and are involved in selenium（Se） metabolism. In this study, we revealed the pivotal role of cytoplasmic TRX pathway in regulating the metabolism of Na2SeO3during the live-cell synthesis of cadmium-selenium quantum dots（Cd Se QDs） in Saccharomyces cerevisiae by regulating the expression level of genes related to TRX pathway and measuring the intracellular content of selenocysteine（Se Cys）. The determination of Se Cys metabolism in yeast with GSH pathway-related genes deleted demonstrated that the TRX pathway played a more significant role in Se Cys metabolism than GSH pathway. A 6.4-fold enhancement in the synthetic yield of Cd Se QDs was achieved through the overexpression of TRX pathway-related genes,improvement of synthetic procedure, and supplementation of GSH based on the understanding of biological *** the mechanism of CdSe QDs live-cell synthesis facilitates the precise manipulation of biological processes for the synthesis of inorganic nanomaterials.

关键词： thioredoxin glutathione quantum dot live-cell synthesis selenium metabolism Saccharomyces cerevisiae

Mass extinctions, their causes and consequences: an interview with Douglas *** and Shuzhong Shen

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National Science Review 2024年第1期11卷 66-70页

作者： Shucheng xie State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences at Wuhan

‘Mass extinctions’ have been a hot topic for several decades. What triggers a mass extinction? How does a mass extinction impact the evolution of life? How does our ecosystem recover after a mass extinction? These questions attracted the interest of both scientists and the public *** spoke to two renowned researchers in the field of mass extinctions: Prof. Douglas H. Erwin from the National Museum of Natural History of the USA, and Prof. Shuzhong Shen from Nanjing University, China.

关键词： Stratigraphy

Recyclable Technology of Thermosetting Resins for High Thermal Conductivity Materials Based on Physical Crushing

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Energy & Environmental Materials 2024年第6期7卷 378-387页

作者： An zhong Congzhen xie Bin Gou Jiangang Zhou Huasong Xu Song Yu Daoming Zhang Chunhui Bi Hangchuan Cai Licheng Li Rui Wang School of Electric Power South China University of TechnologyGuangzhou 510641China

Epoxy resin,characterized by prominent mechanical and electric-insulation properties,is the preferred material for packaging power electronic ***,the efficient recycling and reuse of epoxy materials with thermally cross-linked molecular structures has become a daunting ***,we propose an economical and operable recycling strategy to regenerate waste epoxy resin into a high-performance *** particle size of waste epoxy micro-spheres(100–600μm)with core-shell structure is obtained through simple mechanical crushing and boron nitride surface *** using smattering epoxy monomer as an adhesive,an eco-friendly composite material with a“brick-wall structure”can be *** continuous boron nitride pathway with efficient thermal conductivity endows eco-friendly composite materials with a preeminent thermal conductivity of 3.71 W m^(−1)K^(−1)at a low content of 8.5 vol%h-BN,superior to pure epoxy resin(0.21 W m^(−1)K^(−1)).The composite,after secondary recycling and reuse,still maintains a thermal conductivity of 2.12 W m^(−1)K^(−1)and has mechanical and insulation properties comparable to the new epoxy resin(energy storage modulus of 2326.3 MPa and breakdown strength of 40.18 kV mm^(−1)).This strategy expands the sustainable application prospects of thermosetting polymers,offering extremely high economic and environmental value.

关键词： brick-wall structure epoxy thermosetting physical recycling thermal management

Influence of Electroshocking Treatment on Microstructure and Mechanical Properties of Ti-6.5Al-3.5Mo-1.5Zr-0.3Si Thin-Wall Specimen Manufactured by Laser Melting Deposition

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 145-158页

作者： Yan wen Xuan Sun Jian Zhou Bingliang Liu Haojie Guo Yuxin Li Fei Yin Liqiang Wang Lechun xie Lin Hua Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan430070China Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan430070China Hubei Longzhong Laboratory Xiangyang441000China Shanghai Aircraft Manufacturing Co. Ltd.Commercial Aircraft Corporation of ChinaLtd.Shanghai201324China State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200240China

In order to improve the properties of titanium alloys manufactured by laser melting deposition(LMD),the electroshocking treatment(EST)was proposed in this *** effects of EST on microstructure and mechanical properties of LMD Ti-6.5Al-3.5Mo-1.5Zr-0.3Si were *** results showed that the width of the heat affected band decreased and disappeared under the thermal and athermal effects of EST,resulting in the uniform *** the microstructure,theαlaths became coarser gradually,and the quantity ofα/βinterface was *** reduction of the quantity ofα/βinterface leads to make less resistant to dislocation,resulting in the reduction in hardness and *** discontinuous grain boundaryαphase and nucleationαcolony near grain boundary inhibited the crack propagation and improved the ***,EST can manipulate the microstructure and improve the mechanical properties of LMD titanium alloys.

关键词： Electroshocking treatment(EST) Laser melting deposition(LMD) Titanium alloy Microstructure Mechanical properties

Lipase and photodecarboxylase coexpression: A potential strategy for alkane-based biodiesel production from natural triglycerides

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Chinese Journal of Chemical Engineering 2024年第3期67卷 238-246页

作者： Yong-Yi Zeng Xin-Yi Xu Jin-Xuan xie wen-Li Chen Lan Liu Xin-Jian Yin Bi-Shuang Chen School of Marine Sciences Sun Yat-Sen UniversityZhuhai 519080China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China

Alkane-based biodiesel is considered the next generation of biodiesel owing to its potential environmental benefits and the fact that it exhibits much higher specific caloric values than traditional ***,the formidable obstacle impeding the commercialization of this cutting-edge fuel alternative lies in the cost associated with its *** this study,an engineered strain Escherichia coli(***)showcasing harmonized coexpression of a lipase(from Thermomyces lanuginosus lipase,TLL)and a fatty acid photodecarboxylase(from Chlorella variabilis,CvFAP)was first constructed to transform triglycerides into *** potential of *** BL21(DE3)/pRSFDuet-1-TLL-CvFAP for alkane synthesis was evaluated with tripalmitin as a model substrate under various process *** a comprehensive examination of the reaction parameters,the scope of the biotransformation was expanded to‘real’substrates(vegetable oils).The results showed that bioderived oils can be transformed into alkanes with high yields(0.80-10.20 mmol·L^(-1))under mild conditions(35℃,pH 8.0,and 36 h)and blue light *** selected processes were performed on an increased lab scale(up to 100 ml)with up to 24.77 mmol·L^(-1) tripalmitin,leading to a yield of 18.89 mmol·L^(-1) *** the employment of a method for efficiently producing alkanes under mild conditions and a simple procedure to isolate alkanes from the reaction system,the utilization of sustainable biomass as a fundamental feedstock emerges as the primary solution to lower the cost of alkane-based ***,this study proposes a readily implementable and highly effective approach for alkane-based biodiesel production.

关键词： Alkane-based biodiesel Renewable biomass Co-overexpression Lipase Photodecarboxylase

维普期刊数据库