检索结果-南通市图书馆

Understanding the Thermal Impedance of Silicone Rubber/Hexagonal Boron Nitride Composites as Thermal Interface Materials

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

Chinese Journal of Polymer Science 2024年第3期42卷 352-363,I0008页

作者： Yuan Ji Shi-da Han Hong Wu Shao-Yun Guo Feng-Shun Zhang Jian-Hui Qiu The State Key Laboratory of Polymer Materials Engineering Sichuan Provincial Engineering Laboratory of Plastic/Rubber Complex Processing TechnologyPolymer Research InstituteSichuan UniversityChengdu 610065China Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China Department of Mechanical Engineering Faculty of Systems Science and TechnologyAkita Prefectural UniversityAkita 015-0055Japan

Silicone rubber(SR) composites are most widely used as thermal interface materials(TIMs) for electronics heat dissipation. Thermal impedance as the main bottleneck limiting the performance of TIMs is usually neglected. Herein, the thermal impedance of SR composites loaded with different levels of hexagonal boron nitride(h-BN) as TIMs was elaborated for the first time by the ASTM D 5470 standard test and finite element analysis. It was found that elastic modulus and surface roughness of SR composites increased with the increase of h-BN content, indicating that the conformity was reduced. When the assembly pressure was 0.69 MPa, there existed an optimal h-BN content at which the contact resistance was minimum(0.39 K·cm^(2)·W^(-1)). Although the decreased bond line thickness(BLT) by increasing the assembly pressure was beneficial to reduce the thermal impedance, the proper assembly pressure should be selected to prevent the warpage of the contact surfaces and the increase in contact resistance, according to the compression properties of the SR composites. This study provides valuable insights into fabrication of high-performance TIMs for modern electronic device applications.

关键词： Thermal interface materials Hexagonal boron nitride Thermal impedance Surfaces

data-driven casting defect prediction model for sand casting based on random forest classification algorithm

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

China Foundry 2024年第2期21卷 137-146页

作者： Bang Guan Dong-hong Wang da Shu Shou-qin Zhu Xiao-yuan Ji Bao-de Sun Shanghai Key Lab of Advanced High-Temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Lab of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China Hefei Casting and Forging Factory of Anhui Heli Co. LtdHefei 230000China State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan 430074China

The complex sand-casting process combined with the interactions between process parameters makes it difficult to control the casting quality,resulting in a high scrap rate.A strategy based on a data-driven model was proposed to reduce casting defects and improve production efficiency,which includes the random forest(RF)classification model,the feature importance analysis,and the process parameters optimization with Monte Carlo *** collected data includes four types of defects and corresponding process parameters were used to construct the RF *** results show a recall rate above 90% for all *** Gini Index was used to assess the importance of the process parameters in the formation of various defects in the RF ***,the classification model was applied to different production conditions for quality *** the case of process parameters optimization for gas porosity defects,this model serves as an experimental process in the Monte Carlo method to estimate a better temperature *** prediction model,when applied to the factory,greatly improved the efficiency of defect *** show that the scrap rate decreased from 10.16% to 6.68%.

关键词： sand casting process data-driven method classification model quality prediction feature importance

LLMs in medicine:The need for advanced evaluation systems for disruptive technologies

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

The Innovation 2024年第3期5卷 1-2页

作者： Yi-da Tang Er-dan Dong Wen Gao Department of Cardiology and Institute of Vascular Medicine Peking University Third HospitalBeijing 100191China State Key Laboratory of Vascular Homeostasis and Remodeling Peking UniversityBeijing 100191China University of Health and Rehabilitation Sciences Qingdao 266000China Peking University Beijing 100871China

In an era of rapid advancements in artificial intelligence(AI),the potential role of large language models(LLMs)in the medical field is receiving increasing *** progression of this technology not only highlights upcoming revolutionary changes in medical services but also offers unprecedented opportunities for the health care sector.1 LLMs’formidable capability to process natural language opens vast prospects for application in the medical field,including in the contexts of emergency triage,geriatric care,and digital medical workflows.

关键词： dis highlights services

Reaction mechanism between Al_(2)o_(3)–Mgo refractory materials and rare earth high-carbon heavy rail steel

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 Iron and Steel Research International 2024年第5期31卷 1153-1163页

作者： Yi Wang Guang-jie Song Ping Shen Jian-zhong He da-xian Zhang Jian-xun Fu Center for Advanced Solidification Technology(CAST) School of Materials Science and EngineeringState Key Laboratory of Advanced Special SteelShanghai UniversityShanghai200444China State Key Laboratory of Baiyunebo Rare Earth Resources Research and Comprehensive Utilization Baotou014030Inner MongoliaChina Inner Mongolia Baotou Steel Union Co. Ltd.Baotou014030Inner MongoliaChina

Submerged entry nozzle(SEN)clogging is a major problem affecting the production quality of rare earth steel,and finding a suitable refractory outlet can significantly reduce production *** explore the relationship between refractory composition and interface interaction,unprotected coated Al_(2)o_(3)–Mgo refractories and Sio2-coated Al_(2)o_(3)–Mgo refractories were added to rare earth high-carbon heavy rail steel under laboratory conditions,and the Al_(2)o_(3)–Mgo refractory was found to be more *** results show that,from the epoxy resin side to the refractory side,the contour of the refractory interface reaction layer can be divided into two main layers:an iron-rich reaction layer and an iron-poor reaction *** based on the spherical model suggest that the adhesion force is proportional to the size of the refractory particles and inclusions,and the same result applies to the surface *** the inclusions at a smaller size has a specific effect on alleviating the erosion of *** with the erosion mechanism of Al_(2)o_(3)–Mgo refractories,the interface reaction mechanism between Al_(2)o_(3)–Mgo refractories and molten steel was proposed,which provides ideas for solving SEN clogging.

关键词： Rare earth high-carbon heavy rail steel Al_(2)o_(3)-Mgo refractory Adhesion Surface tension Interface interaction

Predictive value of preoperative routine examination for the prognosis of patients with pT2N0M0 or pT3N0M0 colorectal cancer

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6期16卷 2429-2438页

作者： Peng-Fei Jing Jin Chen En-da Yu Chao-Yu Miao Department of Colorectal Surgery Changhai HospitalSecond Military Medical University/Naval Medical UniversityShanghai 200433China Department of Endocrinology and Metabolism Changhai HospitalSecond Military Medical University/Naval Medical UniversityShanghai 200433China Department of Pharmacology Second Military Medical University/Naval Medical UniversityShanghai 200433China

BACKGRoUND In recent years,the incidence of colorectal cancer(CRC)has been *** the popularization of endoscopic technology,a number of early CRC has been ***,despite current treatment methods,some patients with early CRC still experience postoperative recurrence and *** To search for indicators associated with early CRC recurrence and metastasis to identify high-risk *** A total of 513 patients with pT2N0M0 or pT3N0M0 CRC were retrospectively enrolled in this *** of blood routine test,liver and kidney function tests and tumor markers were collected before *** were followed up through disease-specific database and telephone *** recurrence,metastasis or death were used as the end point of study to find the risk factors and predictive value related to early CRC recurrence and *** We comprehensively compared the predictive value of preoperative blood routine,blood biochemistry and tumor markers for disease-free survival(DFS)and overall survival(oS)of *** multivariate analysis demonstrated that low platelet count was significantly associated with poor DFS[hazard ratio(HR)=0.995,95% confidence interval(CI):0.991-0.999,P=0.015],while serum carcinoembryonic antigen(CEA)level(HR=1.008,95%CI:1.001-1.016,P=0.027)and serum total cholesterol level(HR=1.538,95%CI:1.026-2.305,P=0.037)were independent risk factors for *** cutoff value of serum CEA level for predicting oS was 2.74 ng/*** the oS of CRC patients with serum CEA higher than the cutoff value was worse than those with lower CEA level,the difference between the two groups was not statistically significant(P=0.075).CoNCLUSIoN For patients with T2N0M0 or T3N0M0 CRC,preoperative platelet count was a protective factor for DFS,while serum CEA level was an independent risk factor for *** that these measures are easier to detect and more acceptable to patients,they may have broader applications.

关键词： Colorectal cancer Platelet count Serum carcinoembryonic antigen Total cholesterol level overall survival Disease-free survival

What is the effect of Tribulus terrestris on testicular morphology and sperm production?An experimental study in the rat model

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2024年第1期26卷 67-70页

作者： Marcello Henrique Araujo da Silva Gabriela Faria Buys-Goncalves Joao Henrique Duque Reis Estrada Francisco Jose Barcellos Sampaio Diogo Benchimol de Souza Urogenital Research Unit Rio de Janeiro State UniversityRio de Janeiro 20551-030RJBrazil

The objective of this study was to investigate whether treatment with Tribulus terrestris(Tt)has any impact on the testicular morphology and function in a rodent *** male rats were divided into a control group and a group receiving 100 mg kg^(-1) body weight of Tt *** 4o days of experiment,the animals were submitted to euthanasia;epididymal tail spermatozoa were collected;and spermatozoa concentration,motility,and viability were *** addition,testicles were collected and processed for histomorphometrical *** were compared using the Student's t-test and considered significant when Poncentration,motility,and viability showed no difference between the ***,testicular weight and volume,seminiferous tubule diameter,tunica propria surface density,seminiferous epithelium surface density,and intertubular compartment surface density were statistically similar between the ***,seminiferous epithelium height and tubular lumen surface density were augmented in animals treated with *** with Tt does not cause a major impact on testicular morphology,promoting only subtle *** difference on spermatozoa parameters was observed.

关键词： morphometry testicle Tribulus terrestris

Co_(2) corrosion of X80 steel welded joints under micro-turbulence induced by welding reinforcement height

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 Iron and Steel Research International 2024年第4期31卷 1015-1032页

作者： Xiao-hui Dou Bin Li Zong-hao He Xin-wei Zhang da-lei Zhang Yan Li School of Materials Science and Engineering China University of Petroleum(East China)Qingdao 266580ShandongChina School of Energy and Power Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

Corrosion failure accidents owing to flow erosion and pipeline corrosion frequently occur during *** welding reinforcement height(WRH)can induce locally micro-turbulent flow field,which aggravates local corrosion of welded joints.A high wall shear stress(WsS)experimental setup was established to conduct the online electrochemical corrosion *** influence of WRH sizes on local corrosion of welded joints was studied at different flow *** electrochemical signals of the local corrosion of X80 welded joints at different flow rates were monitored in real time using electrochemical impedance spectroscopy and wire beam *** addition,the corrosion products composition and properties were *** results show that the micro-turbulent flow fields induced by the WRHs can enhance ion mass transfer near the welded *** corrosion products on the WRH surface also present different microscopic morphologies at different flow *** strong flow fields,the locally enhanced wsS can peel off the dense corrosion product partially,leading to the electrochemical distribution of large cathode and small anode,which accelerates the occurrence and development processes of the local corrosion of welded *** scientific guidelines for the corrosion protection of long-distance oil and gas pipelines can be potentially provided.

关键词： X80 steel welded joint Welding reinforcement height Micro-turbulence Co_(2)corrosion-Ion mass transfer

Association between central serous chorioretinopathy and Helicobacter pylori infection: a systematic review and Meta-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

International Journal of ophthalmology(English edition) 2024年第6期17卷 1120-1127页

作者： da-Wen Wu Fei-Peng Jiang Ge Ge Mei-Xia Zhang Department of ophthalmology West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Research Laboratory of Macular Disease West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

AIM:To investigate the association between central serous chorioretinopathy(CSC)and Helicobacter pylori(Hp)by summarizing all available ***:The Scopus,Embase,EBSCo,PubMed,Web of Science,and Cochrane Library databases for all relevant studies published from inception to october 2022 were searched,and manually searched for relevant reference lists as a *** investigating the association between CSC and Hp infection were ***,8 case-control studies were included in the Meta-analysis after study ***:The results showed no significant correlation between Hp infection and CSC[odds ratio(oR)1.89,95%confidential interval(CI)0.58–6.15,I2=96%,P=0.29].After subgroup analysis based on the degree of development of the study(developing/developed countries),it was found that the results of the two subgroups were the same as the whole,and no significant difference between the two subgroups ***-regression showed that the effect of sample size on heterogeneity among studies was more prominent(Pof the sources of ***:This Meta-analysis reveals no significant correlation between Hp infection and CSC,which still warrants further well-designed extensive sample studies to reach a more reliable conclusion and promote a better understanding of the treatment of CSC.

关键词： central serous chorioretinopathy Helicobacter pylori infection retinal diseases Meta-analysis

The Review of Land Use/Land Cover Mapping AI Methodology and Application in the Era of Remote Sensing Big data

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 Geodesy and Geoinformation Science 2024年第3期7卷 1-23页

作者： ZHANG Xinchang SHI Qian SUN Ying HUANG Jianfeng HE da College of Geography and Remote Sensing Sciences Xinjiang UniversityUrumqi 830017China School of Geography and Remote Sensing Guangzhou UniversityGuangzhou 510006China School of Geography and Planning Sun Yat-sen UniversityGuangzhou 510006China School of Atmospheric Sciences Sun Yat-sen UniversityZhuhai 519082China

With the increasing number of remote sensing satellites,the diversification of observation modals,and the continuous advancement of artificial intelligence algorithms,historically opportunities have been brought to the applications of earth observation and information retrieval,including climate change monitoring,natural resource investigation,ecological environment protection,and territorial space *** the past decade,artificial intelligence technology represented by deep learning has made significant contributions to the field of Earth ***,this review will focus on the bottlenecks and development process of using deep learning methods for land use/land cover mapping of the Earth’s ***,it introduces the basic framework of semantic segmentation network models for land use/land cover ***,we summarize the development of semantic segmentation models in geographical field,focusing on spatial and semantic feature extraction,context relationship perception,multi-scale effects modelling,and the transferability of models under geographical ***,the application of semantic segmentation models in agricultural management,building boundary extraction,single tree segmentation and inter-species classification are ***,we discuss the future development prospects of deep learning technology in the context of remote sensing big data.

关键词： remote sensing big data deep learning semantic segmentation land use/land cover mapping