检索结果-南通市图书馆

Modified constitutive models for Inconel 718 considering current density and temperature in electrically assisted forming process

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第2期37卷 524-540页

作者： xuan CUI Rui ZHAO min WAN School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Jiangxi Research Institute of Beihang University Jiangxi 330000China

Electrically Assisted Forming(EAF)technology has obvious advantages in material *** develop an effective constitutive model considering electrical effects,room temperature and electrically assisted quasi-static uniaxial tensile tests were conducted using ultrathin nickelbased superalloy plates with a thickness of 0.25 *** research focused on the two most widely recognized effects:the Joule thermal and the electric athermal *** mechanism of current action can be divided into two scenarios:one considering the Joule thermal effect only,and the other considering both effects *** basic constitutive models,namely the Modified-Hollomon model and the Johnson-Cook(J-C)model,were selected to be optimized through the classification of two different situations,and four optimized constitutive models were *** was found that the J-C model with simultaneous consideration of the Joule thermal effect and electric athermal effect had the best prediction effect by comparing the results of these four ***,the accuracy of the optimization model was verified by finite element simulation of the electrically assisted stretching optimization *** results show that the constitutive model can effectively predict the temperature effect caused by the Joule heat effect and the athermal effect of current on the material.

关键词： Joule heating Elastoplasticity Plastic deformation Superalloys Constitutive models

Reversibly Tuning Electrochemiluminescence with Stimulated Emission Route for Single-Cell Imaging

在线全文

学校读者我要写书评

暂无评论

Research 2024年第3期2023卷 205-215页

作者： Cheng Ma Xiaodan Gou Zejing Xing min-xuan wang Wenlei Zhu Qin Xu Dechen Jiang Jun-Jie Zhu School of Chemistry and Chemical Engineering Yangzhou University.Yangzhou 225002P.R.China State Key Laboratory of Analytical Chemistry for Life Science State Key Laboratory of Pollution Control and Resource ReuseSchool of Chemistry and Chemical EngineeringSchool of the EnvironmentNanjing UniversityNanjing 210023P.R.China.

Electrochemiluminescence (ECL) has established itself as an excellent transduction technique in biosensing and light-emitting device, while conventional ECL mechanism depending on spontaneous emission of luminophores lacks reversibility and tunable emission characters, limiting the universality of ECL technique in the fields of fundamental research and clinical applications. Here, we report the first observation of stimulated emission route in ECL and thus establish a reversible tuning ECL microscopy for single-cell imaging. This microscopy uses a focused red-shifted beam to transfer spontaneous ECL into stimulated ECL, which enables selective and reversible tuning of ECL emission from homogeneous solution, single particles, and single cells. After excluding other possible competitive routes, the stimulated ECL emission route is confirmed by a dual-objective system in which the suppressed spontaneous ECL is accompanied by the enhanced stimulated ECL. By incorporating a commercial donut-shaped beam, the sharpness of single-cell matrix adhesion is improved 2 to 3 times compared with the counterpart in confocal ECL mode. The successful establishment of this stimulated emission ECL will greatly advance the development of light-emitting device and super-resolution ECL microscopy.

关键词： tuning beam limiting

Recent progress in carbene-catalyzed fluoroalkylation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第8期67卷 2448-2460页

作者： Bei Zhang xuan Zhang Jian wang Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing 210044China School of Pharmaceutical Sciences Tsinghua UniversityBeijing 100084China

The fluoroalkyl fragment plays a vital role in various fields such as pharmaceuticals and materials science, and has a significant impact on human life not only on the present but also in the future. The insertion of fluoroalkyl groups into the chemical skeletons can cause considerable alternations in the chemical, physical and biological properties of molecules, which has attracted numerous scientists from different fields. This review focuses on N-heterocyclic carbene(NHC)-catalyzed fluoroalkylation reactions, providing a detailed analysis and summary of the achievements in the past two decades. Many successful examples clearly indicate that NHCs can catalyze the tranformation of fluoroalkylation reagents with various electronic characteristics, whether electrophilic, nucleophilic, or radical precursors. Herein, the fluoroalkylation reactions are classified based on different catalytic modes of NHCs: Lewis base catalysis, Umploung catalysis, radical catalysis and others. Meanwhile, by refining and systematically studying the contribution of NHC catalysis in fluoroalkylation reactions, this review is expected to provide valuable insights and enlightenment for related fields.

关键词： N-heterocyclic carbene fluoroalkylation radical catalysis

Deciphering the population structure and genetic basis of growth traits from whole-genome resequencing of the leopard coral grouper(Plectropomus leopardus)

在线全文

学校读者我要写书评

暂无评论

Zoological Research 2024年第2期45卷 329-340页

作者： Shao-xuan Wu Qi-Fan Zeng Wen-Tao Han Meng-Ya wang Hui Ding ming-xuan Teng ming-Yi wang Pei-Yu Li Xin Gao Zhen-min Bao Bo wang Jing-Jie Hu MOE Key Laboratory of Marine Genetics and Breeding College of Marine Life Sciences/Key Laboratory of Tropical Aquatic Germplasm of Hainan ProvinceSanya Oceanographic InstitutionOcean University of ChinaQingdaoShandong/SanyaHainan 266100/572025China Hainan Seed Industry Laboratory SanyaHainan 572025China Southern Marine Science and Engineer Guangdong Laboratory GuangzhouGuangdong 511458China

The leopard coral grouper(Plectropomus leopardus)is a species of significant economic *** artificial cultivation of *** has thrived in recent decades,the advancement of selective breeding has been hindered by the lack of comprehensive population genomic *** this study,we identified over 8.73 million single nucleotide polymorphisms(SNPs)through whole-genome resequencing of 326 individuals spanning six distinct ***,we categorized 226 individuals with high-coverage sequencing depth(≥14×)into eight clusters based on their genetic profiles and phylogenetic ***,four of these clusters exhibited pronounced genetic differentiation compared with the other *** identify potentially advantageous loci for ***,we examined genomic regions exhibiting selective sweeps by analyzing the nucleotide diversity(θπ)and fixation index(FST)in these four *** these high-coverage resequencing data,we successfully constructed the first haplotype reference panel specific to *** achievement holds promise for enabling high-quality,***,we combined low-coverage sequencing data with imputation techniques for a genome-wide association study,aiming to identify candidate SNP loci and genes associated with growth traits.A significant concentration of these genes was observed on chromosome 17,which is primarily involved in skeletal muscle and embryonic development and cell ***,our detailed investigation of growth-related SNPs across the eight clusters revealed that cluster 5 harbored the most promising candidate SNPs,showing potential for genetic selective breeding *** findings provide a robust toolkit and valuable insights into the management of germplasm resources and genome-driven breeding initiatives targeting ***.

关键词： Plectropomus leopardus Whole-genome resequencing Growth Haplotype reference panel Single nucleotide polymorphisms

Comparative analysis between single-train passing and double-train intersection in a tunnel

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 429-442页

作者： Jianming DU Qian FANG xuan ZHANG Hualao wang Bridge and Tunnel Research Center Research Institute of Highway Ministry of TransportBeijing 100088China Tunnel and Underground Engineering Research Center of ministry of Education Beijing Jiaotong UniversityBeijing 00044China

Aerodynamic pressure significantly impacts the scientific evaluation of tunnel service *** aerodynamic pressure of two trains running in a double-track tunnel is considerably more complicated than that of a single *** used the numerical method to investigate the difference in aerodynamic pressure between a single train and two trains running in a double-track ***,the numerical method was verified by comparing the results of numerical simulation and on-site ***,the characteristics of aerodynamic pressure were ***,the influence of various train-tunnel factors on the characteristics of aerodynamic pressure was *** results show that the aerodynamic pressure variation can be divided into stage I:irregular pressure fluctuations before the train tail leaves the tunnel exit,and stage II:periodic pressure declines after the train tail leaves the tunnel *** addition,the aerodynamic pressure simultaneously jumps positively or drops negatively for a single train or two trains running in double-track tunnel *** pressure amplitude in the two-train case is higher than that for a single *** maximum positive peak pressure difference(P_(STP))and maximum negative peak pressure difference(P_(STN))increase as train speed rises to the power from 2.256 to 2.930 in stage *** P_(STP) and P_(STN) first increase and then decrease with the increase of tunnel length in stage *** P_(STP) and P_(STN) increase as the blockage ratio rises to the power from 2.032 to 2.798 in stages I and II.

关键词： Railway tunnel Aerodynamic effect Pressure characteristic Train speed Tunnel length Blockage ratio

Enterococcus faecalis provides protection during scavenging in carrion crow (Corvus corone)

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Zoological Research 2024年第3期45卷 451-463页

作者： Bin Hu Jia-min wang Qing-Xun Zhang Jing Xu Ya-Nan Xing Bo wang Shu-Yi Han Hong-xuan He CAS Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China Beijing Milu Ecological Research Center Beijing 102600China Beijing Capital International Airport Co. Ltd.Beijing 101300China

The gut microbiota significantly influences host physiology and provides essential ecosystem *** diet can affect the composition of the gut microbiota,the gut microbiota can also help the host adapt to specific dietary *** carrion crow(Corvus corone),an urban facultative scavenger bird,hosts an abundance of pathogens due to its scavenging *** this,carrion crows infrequently exhibit illness,a phenomenon related to their unique physiological *** present,however,the role of the gut microbiota remains incompletely *** this study,we performed a comparative analysis using 16S rRNA amplicon sequencing technology to assess colonic content in carrion crows and 16 other bird species with different diets in Beijing,*** findings revealed that the dominant gut microbiota in carrion crows was primarily composed of Proteobacteria(75.51%)and Firmicutes(22.37%).Significant differences were observed in the relative abundance of Enterococcus faecalis among groups,highlighting its potential as a biomarker of facultative scavenging behavior in carrion ***,*** isolated from carrion crows was transplanted into model mice to explore the protective effects of this bacterial community against Salmonella enterica *** showed that *** down-regulated the expression of pro-inflammatory cytokines tumor necrosis factor alpha(TNF-α),interferon gamma(IFN-γ),and interleukin 6(IL-6),prevented *** colonization,and regulated the composition of gut microbiota in mice,thereby modulating the host’s immune regulatory ***,*** exerts immunoregulatory and anti-pathogenic functions in carrion crows engaged in scavenging behavior,offering a representative case of how the gut microbiota contributes to the protection of hosts with specialized diets.

关键词： Carrion crow Facultative scavenger Gut microbiota Enterococcus faecalis 16S rRNA sequencing

FAM53B promotes pancreatic ductal adenocarcinoma metastasis by regulating macrophage M2 polarization

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2024年第4期16卷 1479-1499页

作者： xuan-Zeng Pei min Cai Da-Wei Jiang Song-Hai Chen Qing-Qing wang Hui-min Lu Yi-Fan Lu Department of Hepatological Surgery The First Hospital of JiaxingJiaxing 314000Zhejiang ProvinceChina Department of General Surgery West China Hospital of Sichuan UniversityChengdu 610044Sichuan ProvinceChina

BACKGROUND Our study investigated the role of FAM53B in regulating macrophage M2 polarization and its potential mechanisms in promoting pancreatic ductal adenocarcinoma(PDAC)*** To further investigate the role of FAM53B in regulating macrophage M2 polarization and its potential mechanism in promoting PDAC *** goal is to determine how FAM53B affects macrophage M2 polarization and to define its underlying mechanism in PDAC *** Cell culture and various experiments,including protein analysis,immunohisto-chemistry,and animal model experiments,were *** compared FAM53B expression between PDAC tissues and healthy tissues and assessed the correlation of FAM53B expression with clinical *** study analyzed the role of FAM53B in macrophage M2 polarization in vitro by examining the expression of relevant ***,we used a murine model to study the role of FAM53B in PDAC metastasis and analyzed the potential underlying *** Our research showed that there was a significant increase in FAM53B levels in PDAC tissues,which was linked to adverse tumor *** findings indicated that FAM53B can enhance macrophage M2 polarization,leading to increased anti-inflammatory factor *** results from the mouse model further supported the role of FAM53B in PDAC metastasis,as blocking FAM53B prevented tumor cell invasion and *** FAM53B promotes PDAC metastasis by regulating macrophage M2 *** discovery could lead to the development of new strategies for treating *** example,interfering with the FAM53B signaling pathway may prevent cancer *** research findings also provide important information for expanding our understanding of PDAC pathogenesis.

关键词： FAM53B Pancreatic ductal adenocarcinoma Tumor metastasis Macrophage polarization

Accelerated heterogenous ring-opening polymerization towards well-defined helical poly(N-allyl alanine)with clickable side chains

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第6期67卷 2056-2062页

作者： Anyao Ma Xin wang Sunting xuan Zhengbiao Zhang College of Chemistry Chemical Engineering and Materials ScienceSoochow UniversitySuzhou215123China State Key Laboratory of Radiation Medicine and Protection Soochow UniversitySuzhou215123China

Well-defined poly(N-allyl alanine)has been synthesized by heterogenous ring-opening polymerization(HROP)of less reactive N-allyl-alanine N-carboxyanhydride,using acetic acid as the catalyst and benzylamine as the initiator,in non-polar ***,the polymerization exhibited typical features of living polymerization though both monomer(liquid)and polymer(solid)have minimal solubility in *** obtained polymer showed a stable helix structure independent of the temperatures screened,as evidenced by circular dichroism ***,the preliminary study demonstrated that the side chains can be post-functionalized through thiol-ene click chemistry with quantitative ***,this work provides guidance for the development of accelerated HROP of other liquid monomers bearing low ***,the helical and functionalizable poly(N-allyl alanine)could be a useful“clickable platform”for the design of variable biomaterials via efficient click chemistry.

关键词： heterogenous ring-opening polymerization controlled polymerization stable helix clickable N-substituted polypeptide di-substituted polypeptoid

Total-factor energy efficiency of ten major global energy-consuming countries

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第3期137卷 41-52页

作者： xuan wang Yonglong Lu Chunci Chen Xiaojie Yi Haotian Cui State Key Laboratory of Urban and Regional Ecology Research Centre for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China State Key Laboratory of Marine Environmental Science and Key Laboratory of the ministry of Education for Coastal Wetland Ecosystems College of the Environment and EcologyXiamen UniversityFujian 361102China University of Chinese Academy of Sciences Beijing 100049China

Improving energy efficiency is regarded as a key path to tackling global warming and achieving the Sustainable Development Goals(SDGs).In 2020,the energy consumption of the world's ten major energy-consuming countries accounted for 66.8%of the global *** paper applied data envelopment analysis(DEA)to calculate these ten major energyconsuming countries'total-factor energy efficiency(TFEE)at national and sectoral levels from 2001-2020,and explored the infuencing factors of total-factor energy efficiency with the Tobit regression *** results showed significant difference in the ten countries'energy *** United States and Germany topped the list for total-factor energy efficiency,while China and India were at the ***,the energy efficiency of the industrial subsector has increased significantly over the past two decades,while that of the other subsectors has been relatively *** industrial structure upgrading,per capita GDP,energy consumption structure,and foreign direct investment had significant impacts on energy efficiency with national *** consumption structure and GDP per capita were determinative factors of energy efficiency.

关键词： Total-factor energy efficiency SBM-UN model Major energy-consuming country Carbon emission reduction