检索结果-南通市图书馆

Mesoscale Mechanical Properties and Influencing Factors of Concrete under Uniaxial Tension

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 Wuhan University of Technology(Materials Science) 2024年第5期39卷 1156-1168页

作者： CHEN Tao LI Kungang xiao Shiyun State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

Monte Carlo simulations were carried out to generate a mesoscale model of concrete with randomly packed aggregates with different shapes and *** mechanical properties of concrete specimens under uniaxial tensile loads were studied using statistical *** results indicated that the entire process of damage and failure of specimens exhibited mainly two failure types:fracture patternsⅠandⅡ.Furthermore,the influences of the aggregate content ratio,aggregate shape,aggregate size,interfacial transition zone(ITZ)strength,and porosity ratio on the concrete specimens were *** numerical simulation results showed that the elastic modulus of the concrete specimens increased approximately linearly with the aggregate volume ratio but decreased linearly with the porosity and was not affected by the ITZ *** tensile strength decreased with the increases in the aggregate content and porosity of the sample,but increased linearly with the ITZ *** addition,the aggregate shape led to a difference in the tensile strength of the concrete.

关键词： concrete mechanical behavior aggregate interfacial transition zone pore

Microbiome in Female Reproductive Health:Implications for Fertility and Assisted Reproductive Technologies

在线全文

学校读者我要写书评

暂无评论

Genomics, Proteomics & Bioinformatics 2024年第1期22卷 5-18页

作者： Liwen xiao Zhenqiang Zuo Fangqing Zhao CAS Key Laboratory of Systems Biology Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China Beijing Institutes of Life Science/Institute of Zoology Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

The microbiome plays a critical role in the process of conception and the outcomes of *** in microbiome homeostasis in women of reproductive age can lead to various pregnancy complications,which significantly impact maternal and fetal *** studies have associated the microbiome in the female reproductive tract(FRT)with assisted reproductive technology(ART)outcomes,and restoring microbiome balance has been shown to improve fertility in infertile *** review provides an overview of the role of the microbiome in female reproductive health,including its implications for pregnancy outcomes and ***,recent advances in the use of microbial biomarkers as indicators of pregnancy disorders are summarized.A comprehensive understanding of the characteristics of the microbiome before and during pregnancy and its impact on reproductive health will greatly promote maternal and fetal *** knowledge can also contribute to the development of ARTs and microbiome-based interventions.

关键词： Microbiome Pregnancy Female reproductive health Assisted reproductive technology Microbial biomarker

Cigarette Use and Secondhand Smoke Exposure Among Secondary School Students—China,2023

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China CDC weekly 2024年第22期6卷 509-515页

作者： Xinying Zeng Shiwei Liu Lin xiao Tobacco Control Office Chinese Center for Disease Control and PreventionBeijingChina

What is already known about this topic?In 2021,the prevalence of experimental and current cigarette use among secondary school students in China stood at 16.7%and 4.7%,***,39.9%of these students were exposed to secondhand smoke at *** is added by this report?In comparison to 2021,the prevalence of current cigarette use remained unchanged at 4.2%in 2023,whereas experimental use declined to 13.7%.Notably,rates were significantly higher among vocational senior high school(VSHS)students relative to their peers in senior high school(SHS)and junior high school(JHS).Furthermore,exposure to secondhand smoke in schools decreased to 35.4%in 2023 from previously recorded levels,with more pronounced reductions observed in JHS and SHS populations and no notable change among VSHS *** are the implications for public health practice?Targeted tobacco control policies are imperative for secondary school students,including the establishment of smoke-free school ***,it is crucial to pay close attention to the needs of VSHS students.

关键词： smoke unchanged senior

Impact of nutritional support on immunity,nutrition,inflammation,and outcomes in elderly gastric cancer patients after surgery

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Surgery 2024年第7期16卷 2175-2182页

作者： xiao-Wan Chen xiao-Chun Guo Fen Cheng Department of Gastrointestinal Surgery Hubei Cancer HospitalWuhan 430079Hubei ProvinceChina Department of Gastroenterology The First People’s Hospital of Jiangxia DistrictWuhan 430200Hubei ProvinceChina

BACKGROUND Postoperative rehabilitation of elderly patients with gastric cancer has always been the focus of clinical *** the intervention by a full-course nutritional support team can have a positive impact on the postoperative immune function,nutritional status,inflammatory response,and clinical outcomes of this special population has not yet been fully *** To evaluate the impact of full-course nutritional support on postoperative comprehensive symptoms in elderly patients with gastric *** This is a retrospective study,including 60 elderly gastric cancer patients aged 70 years and above,divided into a nutritional support group and a control *** nutritional support group received full postoperative nutritional support,including individualized meal formulation,and intravenous and parenteral nutrition supplementation,and was regularly evaluated and adjusted by a professional nutrition *** control group received routine postoperative *** After intervention,the proportion of CD4+lymphocytes(25.3%±3.1%vs 21.8%±2.9%,P<0.05)and the level of immunoglobulin G(12.5 G/L±2.3 G/L vs 10.2 G/L±1.8 G/L,P<0.01)were significantly higher in the nutritional support group than in the control group;the changes in body weight(-0.5 kg±0.8 kg vs-1.8 kg±0.9 kg,P<0.05)and body mass index(-0.2±0.3 vs-0.7±0.4,P<0.05)were less significant in the nutritional support group than in the control group;and the level of C-reactive protein(1.2 mg/L±0.4 mg/L vs 2.5 mg/L±0.6 mg/L,P<0.01)and WBC count(7.2×10^(9)/L±1.5×10^(9)/L vs 9.8×10^(9)/L±2.0×10^(9)/L,P<0.01)were significantly lower in the nutritional support group than in the control *** addition,patients in the nutritional support group had a shorter hospital stay(10.3 d±2.1 d vs 14.8 d±3.6 d,P<0.05)and lower incidence of infection(15%vs 35%,P<0.05)in those of the control *** The intervention by the nutritional support team has a positive impact on postoperative immune function,

关键词： Elderly gastric cancer Postoperative Nutritional support Immune function Inflammatory response Clinical outcome

Berry-Esseen bounds and moderate deviations for the norm, entries and spectral radius of products of positive random matrices

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 Mathematics 2024年第3期67卷 627-646页

作者： Hui xiao Ion Grama Quansheng Liu Institut fur Mathematik und Angewandte Informatik Universitat HildesheimHildesheim 31141Germany Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China LMBA Universite Bretagne SudCNRS UMR 6205Vannes F-56000France

Let(g_(n))_(n≥1) be a sequence of independent and identically distributed positive random d×d matrices and consider the matrix product G_(n)=g_(n)…g_*** suitable conditions,we establish the Berry-Esseen bounds on the rate of convergence in the central limit theorem and Cramer-type moderate deviation expansions,for any matrix norm ‖G_(n)‖ of G_(n),its entries G_(n)^(i,j) and its spectral radius ρ(G_(n)).Extended versions of their joint law with the direction of the random walk G_(n)x are also established,where x is a starting point in the unit sphere of R~d.

关键词： Berry-Esseen bound Cramér-type moderate deviation product of random matrices operator norm entry spectral radius

Attack-Resilient Distributed Cooperative Control of Virtually Coupled High-Speed Trains via Topology Reconfiguration

在线全文

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1066-1068页

作者： Shunyuan xiao xiaohua Ge Qing Wu the Institute of Advanced Technology Nanjing University of Posts and TelecommunicationsNanjing 210023China the School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourne VIC 3122Australia the School of Engineering and Technology Central Queensland UniversityRockhampton QLD 4701Australia

Dear Editor,This letter addresses the resilient distributed cooperative control problem of a virtually coupled train convoy under stochastic disturbances and cyber *** main purpose is to achieve distributed coordinati... 详细信息

关键词： prescribed Speed trains

Uniqueness on Difference Operators of Meromorphic Functions of Infinite Order

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2024年第2期40卷 511-527页

作者： Hui LI Ming Liang FANG xiao YAO School of Science China University of Mining and TechnologyBeijing 100083P.R.China Institute of Mathematics Academy of Mathematics and System SciencesChinese Academy of SciencesBeijing 100190P.R.China School of Sciences Hangzhou Dianzi UniversityHangzhou 310012P.R.China School of Mathematical sciences and LPMC Nankai UniversityTianjin 300071P.R.China

We investigate the uniqueness problems of meromorphic functions and their difference operators by using a new *** is proved that if a non-constant meromorphic function f shares a non-zero constant and ∞ counting multiplicities with its difference operators Δcf(z) and Δ_(c)^(2)f(z), thenΔcf(z)≡Δ_(c)^(2)f(z).In particular,we give a difference analogue of a result of *** method has two distinct features:(ⅰ) It converts the relations between functions into the corresponding *** makes it possible to deal with the uniqueness problem by linear algebra and combinatorics.(ⅱ) It circumvents the obstacle of the difference logarithmic derivative lemma for meromorphic functions of infinite order,since this method does not depend on the growth of the ***,the idea in this paper can also be applied to the case for several variables.

关键词： Uniqueness meromorphic functions difference operators infinite order

Study on impedance spectroscopy based on dynamic equivalent circuit of solar cell

在线全文

学校读者我要写书评

暂无评论

Optoelectronics Letters 2024年第8期20卷 449-453页

作者： xiao Wenbo LI Ao WU Huaming LI Yongbo xiao Bangzhi Key Laboratory of Nondestructive Testing Ministry of EducationNanchang Hangkong UniversityNanchang 330063China Jiangxi Engineering Laboratory for Optoelectronics Testing Technology Nanchang 330063China College of Science and Technology Nanchang Hangkong UniversityGongqingcheng 332020China School of Engineering and Construction Nanchang UniversityNanchang 330031China

This paper investigates the impedance spectroscopy of monocrystalline silicon solar cells(MSSC)and dye-sensitized solar cells(DSSC)using solar cell dynamic equivalent resistor-capacitance(RC)and capacitor sum capacitor(CSC)***,these circuits effectively represent the dynamic behavior of MSSC and ***,the measurement method significantly impacts the accuracy of impedance measurements in the high-frequency ***,the series resistance affects the distance between the left end of the impedance spectroscopy and the origin,while the parallel resistance influences the size of the impedance *** the CSC circuit,the relative magnitudes of dielectric relaxation capacitance and chemical capacitance affect the number and position of arc in the impedance *** value of the dielectric relaxation capacitor determines the number of impedance spectroscopy *** conclusions provide guidelines for improving the accuracy of solar cell impedance measurements.

关键词： spectroscopy impedance capacitance

Cyclic Pulsating Pressure Enhanced Segregating Structuration of Ultra-High Molecular Weight Polyethylene/Graphene Composites as High-performance Light-Weight EMI Shields

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第7期42卷 958-967,I0008页

作者： Yun-Zhi Huang xiao-xiao Liu Lan-Wei Li Guang-Ming Huang Zhao-Xia Huang Jin-Ping Qu National Engineering Research Center of Novel Equipment for Polymer Processing Key Laboratory of Polymer Processing EngineeringMinistry of EducationGuangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced ManufacturingSchool of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou 510641China School of Advanced Manufacturing Technology Guangdong Mechanical&Electrical PolytechnicGuangzhou 510550China

Currently,the enhancement in electromagnetic interference(EMI)performance of polymeric composite generally relies on either improving electrical conductivity(σ)for stronger electromagnetic(EM)reflections or tailoring structure for higher EM ***,we proposed a novel technique called cyclic pulsating pressure enhanced segregating structuration(CPP-SS),which can reinforce these two factors *** structural information was supplied by optical microscopy(OM)and scanning electron microscopy(SEM),both of which confirmed the formation and evolution of segregate structured ultra-high molecular weight polyethylene(UHMWPE)/graphene ***,the result showed that CPP-SS can significantly improve theσof ***,advanced specific EMI shielding efficiency of 31.1 d B/mm was achieved for UHMWPE/graphene composite at 1-mm thickness and a low graphene loading of 5 wt%.Meanwhile,it also confirmed that the intrinsic disadvantage of poor mechanical properties of conventional segregated structure composites can be *** work is believed to provide a fundamental understanding of the structural and performance evolutions of segregated structured composites prepared under CPPSS,and to bring us a simple and efficient approach for fabricating high-performance,strong and light-weight polymeric EMI shields.

关键词： Cyclic pulsating pressure Segregated structure Ultra-high molecular weight polyethylene Graphene Electromagnetic interface