检索结果-南通市图书馆

维普期刊数据库

Detail fatigue rating method based on bimodal Weibull distribution for DED Ti-6.5Al-2Zr-1Mo-1V titanium alloy

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2022年第4期35卷 281-291页

作者： Tianshuai wang xiaofan HE Jinyu wang Yuhai LI School of Aeronautic Science and Engineering Beihang UniversityBeijing 100083China

Previous studies have shown that the fatigue life distribution of metal materials fabricated with Additive Manufacturing(AM) methods, such as Direct Energy Deposited(DED) Ti-6.5Al-2Zr-1Mo-1V alloys, exhibits two peaks. To promote the application of AM in aerospace and other engineering fields, developing a fatigue strength evaluation method suitable for AM materials based on their unique fatigue behaviours and fatigue life distributions is necessary. In this paper, a novel Detail Fatigue Rating(DFR) method was developed to evaluate the fatigue strength of DED Ti-6.5Al-2Zr-1Mo-1V based on a bimodal Weibull distribution and the excessive restriction on the allowable stress of potential was improved. Meanwhile, a Bimodal Weibull distribution model for fatigue life and its parameter estimation method were established based on a twoparameter Weibull distribution. The fatigue life at a specific reliability level and confidence level was calculated by using the bootstrap method. The calculation results showed that fatigue life estimated by using the bimodal Weibull distribution at the high reliability level and high confidence level is higher than that estimated by using the two-parameter Weibull distribution. Furthermore,The S-N curve at the specified confidence level and reliability level was fitted.

关键词： Bimodal weibull distribution Detail fatigue rating method Directed energy deposition Distribution parameter estimation Fatigue reliability

维普期刊数据库

Towards data-driven identiication and control of complex networks

在线全文

学校读者我要写书评

暂无评论

National Science Review 2014年第3期1卷 335-336页

作者： Xiaofan Wang Department of Automation Shanghai Jiao TongUniversity

Control theory has been well recognized as a‘mature’discipline,but research interest has repeatedly been renewed due to the emergence of new viewpoints and introduction of new methodologies[1].Recent interests on identiication and control of complex networks provide excellent examples of such evidence(Fig.1).Uncovering complex networked sys-

关键词： work Towards data-driven identiication and control of complex networks net data

Materials for evaporation-driven hydrovoltaic technology

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Interdisciplinary Materials 2022年第4期1卷 449-470页

作者： Chunxiao Zheng Weicun Chu Sunmiao Fang Jin Tan Xiaofan Wang Wanlin Guo Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education State Key Laboratory of Mechanics and Control of Mechanical StructuresNanjing University of Aeronautics and AstronauticsNanjingChina Institute for Frontier Science Nanjing University of Aeronautics and AstronauticsNanjingChina

Water constitutes the largest energy carrier on earth,absorbing more than 70%of the solar energy received by the earth's surface,yet its low exploitation has been a constant concern.The hydrovoltaic effect is an emerging technology that generates electricity through the direct interaction between nanomaterials and water of various forms(raindrops,waves,flows,moisture,and natural evaporation).Especially,the evaporation-driven hydrovoltaic effect is a spontaneous and ubiquitous process that can directly convert thermal energy from the surrounding environment into electricity without the demand for additional mechanical work,which shows unique advantages compared with other hydrovoltaic effects.A variety of nanostructured materials have been steadily developed for evaporation-driven hydrovoltaic devices(EHDs)in recent years.However,there has been a lack of a clear specification on the selection and design of materials for improving device performance.Herein,we first analyze the mechanisms of EHDs followed by a summarization of the recent advances in materials,including carbon materials,biomass-based materials,metal oxides,composite materials,and others.We then discuss the strategies for improving the energy conversion efficiency and the output power in terms of structural design,surface modification,and interface treatment.Finally,we provide an outlook on the potential applications of electricity generation,sensors,and desalination technology,as well as the challenges and prospects for the development of this emerging technology in the future.

关键词： electric double layer hydrovoltaic effect materials synthesis structural optimization water evaporation

Interatomic electron transfer promotes electroreduction CO_(2)-to-CO efficiency over a CuZn diatomic site

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2023年第7期16卷 8863-8870页

作者： Jican Hao Han Zhu Qi Zhao Jiace Hao Shuanglong Lu Xiaofan Wang Fang Duan Mingliang Du Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China School of Biological and Chemical Sciences Queen Mary University of LondonLondon E14NSUK

Diatomic site catalysts(DACs)with two adjacent atomic metal species can provide synergistic interactions and more sophisticated functionalities to break the bottleneck of intrinsic drawbacks of single atom catalysts(SACs).Herein,we have designed a CuZn diatomic site(CuZn-DAS)electrocatalyst with unique coordination structure(CuN_(4)-ZnN_(4))by anchoring and ordering the spatial distance between the metal precursors on the carbon nitride(C_(3)N_(4))derived N-doped carbon(NC)substrate.The CuZn-DAS/NC shows high activity and selectivity for electroreduction CO_(2)into CO.The Faradaic efficiency for CO of CuZn-DAS/NC(98.4%)is higher than that of Cu single atomic site on NC(Cu-SAS/NC)(36.4%)and Zn single atomic site on NC(Zn-SAS/NC)(66.8%)at-0.6 V versus reversible hydrogen electrode(vs.RHE).In situ characterizations reveal that the CuZn-DAS is more favorable for the formation and adsorption of^(*)COOH than those of the electrocatalysts with single atomic site.Theorical calculations show that the charge redistribution of Zn site in CuZn-DAS/NC caused by the considerable electron transfers from Zn atoms to the adjacent Cu atoms can reduce the adsorption energy barriers for^(*)COOH and^(*)CO production,improving the activity and CO selectivity.

关键词： CuZn diatomic site CO_(2)electroreduction reaction interatomic electron transfer in situ characterizations

Online single-shot characterization of ultrafast pulses from high-gain free-electron lasers

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Fundamental Research 2022年第6期2卷 929-936页

作者： Li Zeng Chao Feng Duan Gu Xiaofan Wang Kaiqing Zhang Bo Liu Zhentang Zhao Institute of Advanced Science Facilities ShenzhenGuangdong 518107China Shanghai Advanced Research Institute Chinese Academy of ScienceShanghai 201210China

X-ray free-electron lasers(FELs)provide cutting-edge tools for fundamental researches to study nature down to the atomic level at a time-scale that fits this resolution.A precise knowledge of temporal information of FEL pulses is the central issue for its applications.Here we proposed and demonstrated a novel method to determine the FEL temporal profiles online.This robust method,designed for ultrafast FELs,allows researchers to acquire real-time longitudinal profiles of FEL pulses as well as their arrive times with respect to the external optical laser with a resolution better than 6 fs.Based on this method,we can also directly measure various properties of FEL pulses and correlations between them online.This helps us to further understand the FEL lasing processes and realize the generation of stable,nearly fully coherent soft X-ray laser pulses at the Shanghai Soft X-ray FEL facility.This method will enhance the experimental opportunities for ultrafast science in various areas.

关键词： X-ray free-electron laser Ultrafast pulses Single-shot characterization Correlation analysis Laser-electron timing feedback

The Strength of Structural Diversity in Online Social Networks

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Research 2021年第1期2021卷 1203-1212页

作者： Yafei Zhang Lin wang Jonathan JHZhu Xiaofan Wang Alex‘Sandy’Pentland Department of Automation Shanghai Jiao Tong University and Key Laboratory of System Control and Information ProcessingMinistry of Education of ChinaShanghai 200240China Department of Media and Communication and School of Data Science City University of Hong KongHong Kong S.A.R.China Department of Automation Shanghai UniversityShanghai 200444China Media Lab Massachusetts Institute of TechnologyCambridgeMA 02139USA

Understanding the way individuals are interconnected in social networks is of prime significance to predict their collective outcomes.Leveraging a large-scale dataset from a knowledge-sharing website,this paper presents an exploratory investigation of the way to depict structural diversity in directed networks and how it can be utilized to predict one’s online social reputation.To capture the structural diversity of an individual,we first consider the number of weakly and strongly connected components in one’s contact neighborhood and further take the coexposure network of social neighbors into consideration.We show empirical evidence that the structural diversity of an individual is able to provide valuable insights to predict personal online social reputation,and the inclusion of a coexposure network provides an additional ingredient to achieve that goal.After synthetically controlling several possible confounding factors through matching experiments,structural diversity still plays a nonnegligible role in the prediction of personal online social reputation.Our work constitutes one of the first attempts to empirically study structural diversity in directed networks and has practical implications for a range of domains,such as social influence and collective intelligence studies.

关键词： collective networks founding

Synthesis of 3-thiocyanated chromones via TCCA/NH_(4)SCN-mediated cyclization/thiocyanation of alkynyl aryl ketones

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Green Synthesis and Catalysis

Green Synthesis and Catalysis 2022年第2期3卷 198-201页

作者： Jiaxi Xiao Zhenkang Ai Xuemin Li Sanqing Tao Bingyue Zhao Xiaofan Wang Xinbo wang Yunfei Du Tianjin Key Laboratory for Modern Drug Delivery&High-Efficiency School of Pharmaceutical Science and TechnologyTianjin UniversityTianjin 300072China School of Environmental Science and Engineering Shandong UniversityQingdao 266237China

3-Thiocyanated chromones was conveniently synthesized from alkynyl aryl ketones using commercially available,inexpensive trichloroisocyanuric acid(TCCA)as oxidant and NH_(4)SCN as thiocyanato(SCN)source.This metalfree approach is postulated to first in situ generate thiocyanogen chloride(Cl-SCN)from the reaction of TCCA and NH_(4)SCN,followed by a rare efficient electrophilic thiocyano oxyfunctionalization of alkynes enabled by the reactive electrophilic species generated thereof.

关键词： Thiocyanation Cyclization TCCA NH_(4)SCN Chromones

Gut-homing α4β7 CD4+ T cells: potential key players in both acute HIV infection and HIV-associated cancers

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Cellular & Molecular Immunology 2018年第2期15卷 190-192页

作者： Yang wang xiaofan Lu Hao Wu Wei Li Center of Interventional Oncology and Liver Diseases Beijing You'an HospitalCapital Medical UniversityBeijing100069China Beijing Key Laboratory for HIV/AIDS Research Beijing100069China Center of Infectious Disease Beijing You'an HospitalCapital Medical UniversityBeijing100069China

During acute human immunodeficiency virus(HIV)infection,depletion of CD4^(+) T cells in the host gut mucosa occurs prior to its occurrence in the peripheral blood and other lymphoid tissues.Expression of integrinα4β7,a gut-homing receptor on CD4^(+) T cells,not only provides a potential receptor for HIV but also plays a critical role in lymphocyte migration from the circulation to the intestine.In our previous study,it was found that circulating gut-homingα4β7 CD4^(+) T cells,including the Th17 and Th1 subsets,were significantly depleted during acute HIV-1 infection.1 Moreover,no gut-homing Treg cells were depleted.Thus,the gut-homing Treg:Th17 ratio was inversely correlated with the CD4 T+cell count.

关键词： α4β7 Th17 acute

Donor age and body weight determine the effects of fecal microbiota transplantation on growth performance,and fecal microbiota development in recipient pigs

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Animal Science and Biotechnology 2022年第5期13卷 1483-1498页

作者： Xiaofan Wang Tsungcheng Tsai Bin Zuo Xiaoyuan Wei Feilong Deng Ying Li Charles V.Maxwell Hua Yang Yingping Xiao Jiangchao Zhao Department of Animal Science Division of AgricultureUniversity of ArkansasFayettevilleARUSA Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise Breeding College of Life Science and EngineeringFoshan UniversityFoshan 528225China State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products Institute of Agro-product Safety and NutritionZhejiang Academy of Agricultural SciencesHangzhouChina

Background:The application of fecal microbiota transplantation(FMT)to improve swine growth performance has been sporadically studied.Most of these studies used a single microbiota source and thus the effect of donor characteristics on recipient pigs’fecal microbiota development and growth performance is largely unknown.Results:In this study,we collected feces from six donors with heavy(H)or light(L)body weight and different ages(d 42,nursery;d 96,growing;and d 170,finisher)to evaluate their effects on the growth performance and fecal microbiota development of recipient pigs.Generally,recipients that received two doses of FMT from nursery and finisher stages donor at weaning(21±2 days of age)inherited the donor’s growth pattern,while the pigs gavaged with grower stage material exerted a numerically greater weight gain than the control pigs regardless of donor BW.FMT from heavier donors(NH,GH,and FH)led to the recipients to have numerically increased growth compared to their lighter counterparts(NL,GL,and FL,respectively)throughout the growing and most finishing stages.This benefit could be attributed to the enrichment of ASV25 Faecalibacterium,ASV61 Faecalibacterium,ASV438 Coriobacteriaceae_unclassified,ASV144 Bulleidia,and ASV129 Oribacterium and decrease of ASV13 Escherichia during nursery stage.Fecal microbiota transplantation from growing and finishing donors influenced the microbial community significantly in recipient pigs during the nursery stage.FMT of older donors’gut microbiota expedited recipients’microbiota maturity on d 35 and 49,indicated by increased estimated microbiota ages.The ageassociated bacterial taxa included ASV206 Ruminococcaceae,ASV211 Butyrivibrio,ASV416 Bacteroides,ASV2 Streptococcus,and ASV291 Veillonellaceae.The body weight differences between GL and GH pigs on d 104 were associated with the increased synthesis of the essential amino acid,lysine and methionine,mixed acid fermentation,expedited glycolysis,and sucrose/galactose degradation.Conclusions:Overall,our study provided insights

关键词： Colonization FMT Growth performance Swine gut microbiome

维普期刊数据库