检索结果-南通市图书馆

Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 155-178页

作者： n.sHAHVEIsI s.FELI Department of Mechanical Engineering Razi UniversityKermanshah ***Iran

The dynamic responses and generated voltage in a curved sandwich beam with glass reinforced laminate(GRL)layers and a pliable core in the presence of a piezoelectric layer under low-velocity impact(LVI)are *** current study aims to carry out a dynamic analysis on the sandwich beam when the impactor hits the top face sheet with an initial *** the layer analysis,the high-order shear deformation theory(HsDT)and Frostig's second model for the displacement fields of the core layer are *** classical non-adhesive elastic contact theory and Hunter's principle are used to calculate the dynamic responses in terms of *** order to validate the analytical method,the outcomes of the current investigation are compared with those gained by the experimental tests carried out by other researchers for a rectangular composite plate subject to the *** element(FE)simulations are conducted by means of the ABAQUs *** effects of the parameters such as foam modulus,layer material,fiber angle,impactor mass,and its velocity on the generated voltage are reviewed.

关键词： analytical model piezoelectric layer curved sandwich beam glass reinforced laminate(GRL) pliable core low-velocity impact(LVI) classical non-adhesive elastic contact theory

The effect of ethanol fuel dilution on oil performance and MoDTC tribofilms formation and composition

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Friction 2024年第9期12卷 2108-2125页

作者： Juan RUIZ-ACERO Felipe KEssLER Henara costa Tiago COUssEAU Polytechnic school Universidade de São PauloSão Paulo 05508-030Brazil school of Food and Chemistry Universidade Federal do Rio GrandeRio Grande 96203-000Brazil school of Engineering Universidade Federal do Rio GrandeRio Grande 96203-900Brazil Mechanical Engineering Department Univ.Tecnológica Federal do ParanáCuritiba 81280-340Brazil University of newcastle CallaghanSW 2308Australia

Ethanol has emerged as a promising alternative to fossil fuels,but its use can lead to significant dilution in lubricants,particularly during cold start or heavy *** dilution can affect the performance of additives,including friction modifiers like molybdenum dithiocarbamate(MoDTC),which are designed to reduce friction under extreme contact *** research suggests that ethanol may impact the performance of MoDTC,prompting this study’s goal to investigate the effects of ethanol on MoDTC tribofilms and their friction response under boundary lubrication ***,reciprocating tribological tests were performed with fully formulated lubricants containing MoDTC with varying ethanol *** results indicate that a critical ethanol dilution level inhibits friction reduction by MoDTC activation,resulting in friction coefficients(COFs)similar to the base *** tested with simple mixtures of polyalphaolefin(PAO)+MoDTC showed increased COFs with added *** of tested surfaces using Raman spectroscopy,X-ray photoelectron spectroscopy(XPs),and X-ray absorption spectroscopy near the edge structure(XAnEs)revealed the presence of sulfates,MoO_(3),Mos_(2),and Mos_(x)O_(y)compounds in the tribofilms formed on the surfaces,with and without ethanol diluted in the ***,the addition of ethanol increased the sulfates and MoO_(3)content of the tribofilms at the expense of friction-reducing compounds such as Mos_(2)and Mos_(x)O_(y).These findings suggest that ethanol dilution in lubricants containing MoDTC creates an oxygen-rich interfacial medium that favors the formation of compounds with insufficient friction-reducing capabilities.

关键词： molybdenum dithiocarbamate(MoDTC) ethanol tribofilm friction modifier additive lubricant

My enemy’s enemies are my friends:Alternative sources of support in multi-party races

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Economic and Political studies 2024年第3期12卷 285-317页

作者： Carlos costa school of Public and International Affairs Wright State UniversityDaytonOHUSA

The research on redistributive strategies to secure support has been dominated by a core and swing voter model,which pits two parties against each other in a costly race for *** are other options beyond targeting either swing or one’s own core voters?This paper identifies a political scenario where core supporters from other parties are viable targets and sets out to test three dimensions that indicate when actors can effectively target *** paper’s main expectation is that by accounting for voters’ideological affinity,levels of fragmentation,and the potential to deliver their votes,parties can effectively target other parties’core *** case of Brazil’s Bolsa Famılia delivers evidence for the hypotheses.

关键词： Multi-party races coreand swing conditionalcash transfer BolsaFamılia

Colorectal cancer screening:A review of current knowledge and progress in research

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 Oncology 2024年第4期16卷 1119-1133页

作者： sara Ramos Lopes Claudio Martins In.s.costa santos Madalena Teixeira Élia Gamito Ana Luisa Alves Department of Gastroenterology Centro Hospitalar de SetúbalSetúbal 2910-446Portugal

Colorectal cancer(CRC)is one of the most prevalent malignancies worldwide,being the third most commonly diagnosed malignancy and the second leading cause of cancer-related deaths *** the progress in screening,early diagnosis,and treatment,approximately 20%-25%of CRC patients still present with metastatic disease at the time of their initial ***,the burden of disease is still expected to increase,especially in individuals younger than 50 years old,among whom early-onset CRC incidence has been *** and early detection are pivotal to improve CRC-related *** is well established that CRC screening not only reduces incidence,but also decreases deaths from *** screening strategies have proven effective in decreasing both CRC incidence and mortality,though variations in efficacy have been reported across the ***,uncertainties persist regarding the optimal screening method,age intervals and ***,adherence to CRC screening remains globally *** recent years,emerging technologies,notably artificial intelligence,and non-invasive biomarkers,have been developed to overcome these ***,controversy exists over the actual impact of some of the new discoveries on CRC-related outcomes and how to effectively integrate them into daily *** this review,we aim to cover the current evidence surrounding CRC *** will further critically assess novel approaches under investigation,in an effort to differentiate promising inno-vations from mere novelties.

关键词： Colorectal cancer screening Review Oncology Artificial intelligence

Towards defining soil quality of Mediterranean calcareous agricultural soils:Reference values and potential core indicator set

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International soil and Water Conservation Research 2024年第1期12卷 145-155页

作者： Germán A.Durán Daniel sacristán Edelweis Farrús Jaume Vadell Institut de Recerca i FormacióAgrària i Pesquera de les Illes Balears C/Eusebi Estada14507009PalmaSpain Plant Biology Department University of Valencia46100BurjassotValenciaSpain soil and Environmental Quality Department Centro de Investigaciones sobre Desertificación-CIDE(CSIC-Universitat de València-Generalitat Valenciana)Carretera Moncada-Náquera km 4.546113MoncadaValenciaSpain Universitat de les Illes Balears Cra.De Valldemossakm 7507122PalmaSpain

To avoid soil degradation,adapt to climate change and comply with the sustainable Development goals 2030(Un General Assembly),establishing the quality/fertility of the agricultural soils of the Mediterranean region and evaluate how these evolve with time is *** enables adequate management practices to be *** Mediterranean calcareous region has received little attention in this sense,in spite its soil ***,24 different representative calcareous agricultural soils of the Mediterranean region,including the main management strategies of agricultural soils(rainfed and irrigated),were sampled from the island of Mallorca;and their physical,chemical and biological properties *** values obtained for most of the soil characteristics allowed to establish an initial approach to the reference values for the type of calcareous agricultural soils considered,and to clearly distinguish the effect of rainfed or irrigation management practices on soils properties and *** enzyme activities were not stimulated by the irrigation conditions assayed or they were only in dry conditions,suggesting optimum enzyme activities could be obtained when alternating dry and humid soil *** organic carbon,calcium carbonate and active lime revealed of significant importance in the collection of ***,the results obtained clearly indicate the heterogeneity of the region and its implications on the different soil ***,this study could serve as a starting point to adequately establish the quality(fertility)for Mediterranean calcareous agricultural soils and their reference values by conducting further research in this region and including more type of soils.

关键词： soil fertility Mediterranean agricultural soils Calcareous soils soil enzymes soil management

novel classification of gastric polyps:The good,the bad and the ugly

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 Gastroenterology 2024年第31期30卷 3640-3653页

作者： Deborah costa Daryl Ramai Alberto Tringali Department of Digestive Endoscopy and Gastroenterology AULSS2Conegliano HospitalConegliano 31015Italy Department of Gastroenterology Division of Hepatology and EndoscopyBrigham and Women's HospitalBostonMA 02115United States

Gastric polyps(GPs)are increasingly *** upper endoscopy,they should be examined with white light and occasionally chromoendoscopy,and their morphology classified according to the Paris *** GPs have a typical endoscopic appearance and can be associated with diseases like Helicobacter pylori *** examination is necessary for an accurate *** most polyps are non-neoplastic and do not require treatment,some carry a risk of malignancy or are already ***,understanding the diagnosis,classification,and management of GPs is crucial for patient *** new classification categorizes GPs into"good","bad",and"ugly"based on their likelihood of becoming *** aim to provide descriptions of the endoscopic appearance,pathology,treatment,and follow-up for different GPs,as well as clinical management flowcharts.

关键词： Gastric polyps Fundic gland polyps Hyperplastic polyps Adenomas neuroendocrine tumors Early gastric cancer

Early Phases of star Formation: Testing Chemical Tools

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 in Astronomy and Astrophysics 2024年第1期24卷 96-118页

作者： n.C.Martinez s.Paron COnICET-Universidad de Buenos Aires.Instituto de Astronomía y Física del Espacio Ciudad Universitaria(C1428EGA)Ciudad Autónoma de Buenos AiresArgentina

star-forming processes strongly influence the IsM ***,many high-quality databases are available at millimeter *** them,it is possible to carry out studies that review and deepen previous *** these studies involve large samples of sources,it is preferred to use direct tools to study the molecular *** the aim of testing these tools such as the use of the HCn/HnC ratio as a thermometer,and the use of H^(13)CO^(+),HC_(3)n,n_(2)H^(+) and C_(2)H as "chemical clocks," we present a molecular line study toward 55 sources representing massive young stellar objects at different evolutionary stages:infrared dark clouds(IRDCs),highmass protostellar objects(HMPOs),hot molecular cores(HMCs) and ultracompact H II *** found that the use of the HCn/HnC ratio as a universal thermometer in the IsM should be taken with care because the HCn optical depth is a big issue that can affect the ***,this tool should be utilized only after a careful analysis of the HCn spectrum,checking that no line,neither the main nor the hyperfine ones,presents absorption *** point out that the analysis of the emission of H^(13)CO^(+),HC_(3)n,n_(2)H^(+) and C_(2)H could be useful to trace and distinguish regions among IRDCs,HMPOs and *** molecular line widths of these four species increase from the IRDC to the HMC stage,which can be a consequence of the gas dynamics related to the starforming processes taking place in the molecular *** results not only contribute with more statistics,acting as a probe of such chemical tools,useful to obtain information in large samples of sources,but also complement previous works through the analysis of other types of sources.

关键词： stars:formation IsM:molecules IsM:clouds

Dispersion effect of nano-structure pyrolytic carbon on mechanical,electrical,and microstructural characteristics of cement mortar composite

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

International Journal of smart and nano Materials 2024年第3期15卷 534-578页

作者： n.K.Karthikeyan s.Elavenil school of Civil Engineering Vellore Institute of TechnologyChennaiIndia

In material science,converting waste into nanomaterials by green technologies highlights the interest in producing sus-tainable carbon nanomaterial(sCn).This study first-ever uti-lized tyre-char as a nano-structure Pyrolytic Carbon(nsPC)to develop electrically conductive *** other car-bon nanomaterials,the efficiency of nsPC particle as an sCn in developing electrically conductive composites was investi-gated in terms of dispersion,mechanical,water absorption,electrical resistivity,and *** results of sedi-mentation and zeta potential(-19 mV)showed the excellent dispersion of nsPC particle in water with the combined effect of superplasticizer and *** compressive(40.37%)and flexural strength(10.76%)than that of plain cement mortar composite(CMC)is achieved with 2 wt.%and 1.5 wt.%of nsPC particle,*** water absorption rate and volume of permeable voids were reduced,exhibiting less *** percolation zone of AC and DC resis-tivity of nsPC composite ranges between 1 and 2 wt.%,and the established percolation threshold is at 2 wt.%.XRD analysis showed C-s-H formation consistently increased with curing age,and HR-sEM with EDAX analysis exhibits the dense micro-structure and well-distributed nsPC particle at the *** experimental outcomes significantly enhanced the relia-bility and provided a framework for tailoring nsPC particle as sCn for developing electrically conductive composite.

关键词： sustainable nanomaterial dispersion mechanical properties electrical resistivity microstructure analysis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Genes & Diseases 2024年第3期11卷 66-68页

作者： Aswathi n Jincy M.Jose sreelata B.nair Prabha s.n Pappachan s Department of Medical Genetics Lifeline Super Specialty HospitalPathanamthittaKerala 691523India Lifeline super specialty Hospital PathanamthittaKerala 691523India

Alagille syndrome(ALGs;OMIM#118450)is a highlyvariable,multi-systemic,autosomal dominant disorder,caused by mutations in the Jagged Canonical notch Ligand 1(JAG1)gene(20p12.2)or in the neurogenic locus notch homolog protein 2(nOTCH2)gene(1p13).^(1)It primarily affects the liver,heart,eyes,face,kidney,skin,vertebrae,and skeleton.^(1,2)The JAG1 gene has 26 exons and about 90%of the ALGs cases result from pathogenic variants in the JAG1 and around 7%of cases have deletions in chromosome 20 that include this gene.

关键词： JAG1 cases notch

Brain dysfunctions and neurotoxicity induced by psychostimulants in experimental models and humans:an overview of recent findings

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

neural Regeneration Research 2024年第9期19卷 1908-1918页

作者： Marcello serra nicola simola Alexia E.Pollack Giulia costa Department of Biomedical sciences Section of NeuroscienceUniversity of CagliariCagliariItaly Department of Biology University of Massachusetts-BostonBostonMAUSA

Preclinical and clinical studies indicate that psychostimulants,in addition to having abuse potential,may elicit brain dysfunctions and/or neurotoxic *** toxicity induced by psychostimulants may pose serious health risks since the recreational use of these substances is on the rise among young people and *** present review provides an overview of recent research,conducted between 2018 and 2023,focusing on brain dysfunctions and neurotoxic effects elicited in experimental models and humans by amphetamine,cocaine,methamphetamine,3,4-methylenedioxymethamphetamine,methylphenidate,caffeine,and *** elucidation of factors and mechanisms that underlie psychostimulant-induced brain dysfunction and neurotoxicity is crucial for understanding the acute and enduring noxious brain effects that may occur in individuals who use psychostimulants for recreational and/or therapeutic purposes.

关键词： 3,4-methylenedioxymethamphetamine amphetamine caffeine cell cultures cocaine methamphetamine methylphenidate neurotoxicity nicotine