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Numerical analysis and experimental validation of surface roughness and morphology in honing of Inconel 718 nickel-based superalloy

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Advances in Manufacturing 2023年第1期11卷 130-142页

作者： Chang-Yong Yang Zhi Wang Hao Su Yu-Can fu nian-Hui Zhang Wen-Feng Ding Jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology Nanjing University of Aeronautics and AstronauticsNanjing210016People’s Republic of China College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing210016People’s Republic of China

Honing is an important technology for machining onboard system parts.The parts are usually made of difficult-to-machining materials,e.g.,Inconel 718 superalloy.Honing can improve the finishing accuracy and surface quality.However,the selection of the honing parameters was primarily based on the results of a large number of experiments.Therefore,the establishment of a reliable model is needed to predict the honed surface roughness and morphology,and offers a theoretical direction for the choice of parameters.In the present study,a numerical simulation model was constructed for analysis of the honing process by Python.The oilstone,workpiece surface morphology and motion trajectory were discretized by Python,and the machined surface was obtained by trajectory interference.Firstly,based on the statistical analysis of the surface topography of oilstone,the shape of grains was simplified and the surface topography of oilstone was built accordingly.Then,the initial surface morphology of the workpiece was constructed and the trajectory of grains on the workpiece surface was analyzed,which showed the distribution of the removed material.Meanwhile,the plastic deformation of material was analyzed in the simulation model.The critical depth of three stages of contact between grains and workpiece was calculated by the theoretical formula:scratching,ploughing and cutting.By analyzing the distribution of bulge,the plastic deformation in ploughing and cutting stage was studied.further,the simulated results of honed surface roughness and morphology were validated and agreed reasonably well with the honing experiment.Finally,the effects of honing process parameters,including grain size,tangential speed,axial speed,radial speed and abrasive volume percentage,on the surface roughness of the workpiece were analyzed by the simulation model.

关键词： Numerical analysis Surface roughness Plastic deformation Morphology

Relation Between Cellular Senescence and Liver Diseases

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Chinese Medical Sciences Journal 2016年第2期31卷 121-126页

作者： Guo-wen Li Xue-feng Yang Nian Fu Yan Ou-yang Kai Qing Department of Gastroenterology the Affiliated Nanhua Hospital of University of South China

Cellular senescence refers to a process that cellular proliferation and differentiation modulated by the multiple stimulating factors gradually decline. Aging cells present the irreversible stop of proliferation and differentiation and change in secretory function because the cell cycle of aging cells is steadily blocked at some point. It has have been shown that cellular senescence plays an important role in the occurrence and development of liver diseases. In this paper, we review the advances in relations between cellular senescence and liver diseases.

关键词： cellular senescence mechanism liver diseases liver fibrosis liver cancer

Asymmetric hydroazidation ofα-substituted vinyl ketones catalyzed by chiral primary amine

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Chinese Chemical Letters 2017年第5期28卷 1083-1086页

作者： Zai-Kun Xue nian-Kai fu San-Zhong Luo Beijing National Laboratory for Molecular Sciences(BNLMS) CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SdencesBeijing 100190China

We report herein the first example of asymmetric hydroazidation of α-substituted vinyl ketones by using chiral primary amines as the catalysts.A simple chiral primary-tertiary diamine catalyst derived from lphenylalanine was found to readily promote this aza-Michael addition reaction with enamine protonation as the key stereogenic step,thus enabling the effective synthesis of α-chiral β-azido ketones with good yields and moderate enantioselectivities.

关键词： Chiral primary amine catalysis Hydroazidation Enamine protonation α-Substituted vinyl ketones Aza-Michael addition Chiral β-azido ketones

Vitreous substitutes: challenges and directions

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International Journal of Ophthalmology(English edition) 2015年第3期8卷 437-440页

作者： Qian-Ying Gao Yue fu Yan-nian Hui State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat-sen University Department of Ophthalmology Xijing Hospital the Fourth Military Medical University

The natural vitreous body has a fine structure and complex functions. The imitation of the natural vitreous body by vitreous substitutes is a challenging work for both researchers and ophthalmologists. Gases, silicone oil, heavy silicone oil and hydrogels, particularly the former two vitreous substitutes are clinically widely used with certain complications. Those, however, are not real artificial vitreous due to lack of structure and function like the natural vitreous body. This article reviews the situations, challenges, and future directions in the development of vitreous substitutes, particularly the experimental and clinical use of a new artificial foldable capsular vitreous body.

关键词： vitreous substitute artificial vitreous foldable capsular vitreous body silicone oil

Genomic and transcriptional changes in response to pinene tolerance and overproduction in evolved Escherichia coli

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Synthetic and Systems Biotechnology 2019年第3期4卷 113-119页

作者： fu-Xing Niu Yuan-Bin Huang Liang-nian Ji Jian-Zhong Liu Institute of Synthetic Biology MOE Key Laboratory of Bioinorganic and Synthetic ChemistrySchool of Life SciencesSun Yat-Sen UniversityGuangzhou 510275China

α-Pinene is an important monoterpene,which is widely used as a flavoring agent and in fragrances,pharmaceuticals and biofuels.Although an evolved strain Escherichia coli YZFP,which had higher tolerance to pinene and titer,has been successfully used to produce high levels of pinene,the pinene titer is much lower than that of hemiterpene(isoprene)and sesquiterpenes(farnesene)to date.Moreover,the overall cellular physiological and metabolic changes caused by higher tolerance to pinene and overproduction of pinene remains unclear.To reveal the mechanism of Escherichia coli YZFP with the higher tolerance to pinene and titer,a comparative genomics and transcriptional level analyses combining with CRISPR activation(CRISPRa)and interference(CRISPRi)were carried out.The results show that the tolerance to pinene and the overproduction of pinene in E.coli may be associated with:1)the mutations of the DXP pathway genes,the rpoA and some membrane protein genes,and their upregulations of transcription levels;and 2)the mutations of some genes and their downregulation of transcriptional levels.These comparative omics analyses provided some genetic modification strategies to further improve pinene production.Overexpression of the mutated cbpA,tabA,pitA,rpoA,sufBCDS,mutS,ispH,oppF,dusB,dnaK,dxs,dxr and flgFGH genes further improved pinene production.This study also demonstrated that combining comparative omics analysis with CRISPRa and CRISPRi is an efficient technology to quickly find a new metabolic engineering strategy.

关键词： Comparative omics analysis CRISPRa CRISPRi Pinene Escherichia coli Biosynthesis

Roles of Long-chain Acyl Coenzyme A Synthetase in Absorption and Transport of Fatty Acid

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Chinese Medical Sciences Journal 2016年第1期31卷 62-64页

作者： Fan Gao Xue-feng Yang Nian Fu Yang Hu Yan Ouyang Kai Qing 无 Department of Gastroenterology the Affiliated Nanhua Hospital of University of South China Hengyang 421002 Hunan China Department of Nephrology Ruijin Hospital Shanghai Jiaotong University School of Medicine Shanghai 200025 China Department of Hematology Ruijin Hospital Shanghai Jiaotong University School of Medicine Shanghai 200025 China

Long-chain acyl coenzyme A synthetase(ACSL) is a member of the synthetase family encoded by a multigene family;it plays an important role in the absorption and transport of fatty acid.Here we review the roles of ACSL in the regulating absorption and transport of fatty acid,as well as the connection between ACSL and some metabolic diseases.

关键词：酰基辅酶A 吸收转运脂肪酸合成酶长链多基因家族代谢性疾病

Effects of individual heterogeneity on social contagions

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Chinese Physics B 2024年第5期33卷 737-747页

作者：年福忠杨宇 School of Computer and Communication Lanzhou University of TechnologyLanzhou 730000China

Despite having significant effects on social contagions,individual heterogeneity has frequently been overlooked in earlier studies.To better understand the complexity of social contagions,a non-Markovian model incorporating heterogeneous social influence and adoption thresholds is introduced.For theoretical analysis,a generalized edge-based compartmental theory which considers the heterogeneities of social influence and adoption thresholds is developed.Focusing on the final adoption size,the critical propagation probability,and the phase transition type,social contagions for adoption thresholds that follow normal distributions with various standard deviations,follow various distributions,and correlate with degrees are investigated.When thresholds follow normal distributions,a larger standard deviation results in a larger final adoption size when the information propagation probability is relatively low.However,when the information propagation probability is relatively high,a larger standard deviation results in a smaller final adoption size.When thresholds follow various distributions,crossover phenomena in phase transition are observed when investigating the relationship of the final adoption size versus the average adoption threshold for some threshold distributions.When thresholds are correlated with degrees,similar crossover phenomena occur when investigating the relationship of the final adoption size versus the degree correlation index.Additionally,we find that increasing the heterogeneity of social influence suppresses the effects of adoption threshold heterogeneity on social contagions in three cases.Our theory predictions agree well with the simulation results.

关键词： complex networks social contagions heterogeneity phase transition

Core muscle functional strength training for reducing the risk of low back pain in military recruits:An open-label randomized controlled trial

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Journal of Integrative Medicine 2022年第2期20卷 145-152页

作者： Xin Wang Wen-juan Song Yi Ruan Bing-chu Li Can Lü nian Huang Fan-fu Fang Wei Gu School of Traditional Chinese Medicine Naval Medical UniversityShanghai 200433China Department of Rehabilitation Changhai HospitalNaval Medical UniversityShanghai 200433China School of Mechanical Engineering University of Shanghai for Science and TechnologyShanghai 200093China

Background:Core muscle functional strength training(CMFST)has been reported to reduce injuries to the lower extremity.However,no study has confirmed whether CMFST can reduce the risk of low back pain(LBP).Objective:This study identified the effects of CMFST on the incidence of LBP in military recruits.Design,setting,participants and intervention:We performed a prospective,open-label,randomized,controlled study in a population of young healthy male naval recruits from a Chinese basic combat training program.Participants were randomly assigned to either the core group or the control group.In additional to normal basic combat training,recruits in the core group underwent a CMFST program for 12 weeks,while recruits in the control group received no extra training.Main outcome measures:At the beginning of the study and at the 12 th week,the number of participants with LBP was counted,and lumbar muscle endurance was measured.In addition,when participants complained of LBP,they were assessed using the visual analog scale(VAS)and Roland Morris Disability Questionnaire(RMDQ).Results:A total of 588 participants were included in the final analysis(295 in the core group and 293 in the control group).The incidence of LBP in the control group was about twice that of the core group over the 12-week study(20.8%vs 10.8%,odds ratio:2.161–2.159,Pfunction of LBP during basic military training.

关键词： Low back pain Core exercise Recruits Randomized controlled trial

Tension Control of Web Winding Systems for Speed-up Phase

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Tension Control of Web Winding Systems for Speed-up Phase