检索结果-南通市图书馆

Design and preparation of a crosslinkable,oil-resistant,and bio-based elastomer from fumarate

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2期67卷 622-631页

作者： Hui yang Haijun ji Xinxin Zhou Shihan yang Liwei Li Chaoying Sun Weiwei Lei Runguo Wang Liqun Zhang Beijing State Key Laboratory of Organic-Inorganic Composites&Beijing Laboratory of Biomedical Materials Beijing University of Chemical TechnologyBeijing100029China Hubei Key Laboratory of Polymer Materials Faculty of Materials Science and EngineeringHubei UniversityWuhan430062China

Poly(diethyl fumarate-co-methoxyethyl acrylate-co-vinyl chloroacetate)(PDEFMV),a novel bio-based elastomer with a saturated structure,was synthesized via redox emulsion *** glass-transition temperatures of PDEFMV,adjusted through the variation of the diethyl fumarate-to-methoxyethyl acrylate feeding ratio,ranged from-36.1 to-14.8 ℃.The number-average molecular weights of PDEFMV ranged from 384,000 to 46,000 g/*** designing the molecular structure,vinyl chloroacetate was used to provide active sites for subsequent vulcanization and *** active chlorine groups within the PDEFMV chain reacted with the crosslinking agent trithiocyanuric acid under high temperature and pressure to form a nonsulfur crosslinked three-dimensional network *** achieve the desired properties,carbon black(CB,N330) was incorporated to reinforce PDEFMV,leading to the formation of PDEFMV/CB composites.A comprehensive study was conducted on the high-temperature oil resistance of PDEFMV/CB *** immersion in IRM903 oil at temperatures of 150 and 200 ℃ for 72 h,the mass and volume changes in PDEFMV/CB were lower than those observed in commercially available acrylate rubber(AR)/CB,indicating that PDEFMV exhibited superior oil ***,the aging characteristics and mechanisms of oil resistance in the PDEFMV/CB and AR/CB composites were investigated at different temperatures(150,200,and 250 ℃).The results provide insights into the operational temperature ranges suitable for PDEFMV/CB and offer valuable guidance for potential industrial applications.

关键词： diethyl fumarate molecular design bio-based elastomer solvent-free synthetic route high-temperature oil resistance

Uncertainty and sensitivity analysis of in-vessel phenomena under severe accident mitigation strategy based on ISAA-SAUP program

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第1期35卷 108-123页

作者： Hao yang ji-Shen Li Zhi-Ran Zhang Bin Zhang jian-Qiang Shan School of Nuclear Science and Technology Xi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an 710049China

The phenomenology involved in severe accidents in nuclear reactors is highly ***,integrated analysis programs used for severe accident analysis heavily rely on custom empirical parameters,which introduce considerable ***,in recent years,the field of severe accidents has shifted its focus toward applying uncertainty analysis methods to quantify uncertainty in safety assessment programs,known as“best estimate plus uncertainty(BEPU).”This approach aids in enhancing our comprehension of these programs and their further development and *** study concentrates on a third-generation pressurized water reactor equipped with advanced active and passive mitigation *** an Integrated Severe Accident Analysis Program(ISAA),numerical modeling and uncertainty analysis were conducted on severe accidents resulting from large break loss of coolant *** uncertainty parameters of the ISAA program were meticulously *** Wilks'formula,the developed uncertainty program code,SAUP,was employed to carry out Latin hypercube sampling,while ISAA was employed to execute batch *** analysis was then conducted on two figures of merit,namely hydrogen generation and the release of fission products within the pressure *** calculations revealed that hydrogen production and the fraction of fission product released exhibited a normal distribution,ranging from 182.784 to 330.664 kg and from 15.6 to 84.3%,*** ratio of hydrogen production to reactor thermal power fell within the range of 0.0578–0.105.A sensitivity analysis was performed for uncertain input parameters,revealing significant correlations between the failure temperature of the cladding oxide layer,maximum melt flow rate,size of the particulate debris,and porosity of the debris with both hydrogen generation and the release of fission products.

关键词： Gen-III PWR Severe accident mitigation Wilks’formula Hydrogen Fission products Uncertainty and sensitivity analysis

Recent advances in promising drugs for primary prevention of gastroesophageal variceal bleeding with cirrhotic portal hypertension

在线全文

学校读者我要写书评

暂无评论

Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 4-13页

作者： ji-Yao Sheng Zi-Fan Meng Qiao Li Yong-Sheng yang Department of Hepatobiliary and Pancreatic Surgery the Second Hospital of Jilin UniversityChangchun 130041China jilin Engineering Laboratory for Translational Medicine of Hepatobiliary and Pancreatic Diseases the Second Hospital of Jilin UniversityChangchun 130041China

Background:Gastroesophageal variceal bleeding is one of the most severe complications of patients with *** primary prevention drugs,including non-selectiveβ-blockers,have effectively reduced the incidence of bleeding,their efficacy is limited due to side effects and related *** recent advances in precision medicine,precise drug treatment provides better treatment *** sources:Literature search was conducted in PubMed,MEDLINE and Web of Science for relevant articles published up to May *** on clinical trials was obtained from https://***/and http://***/.Results:The in-depth understanding of the pathogenesis and advances of portal hypertension has enabled the discovery of multiple molecular targets for promising *** to the site of action,these drugs could be classified into four classes:intrahepatic,extrahepatic,both intrahepatic and extrahepatic targets and *** these classes of drugs offer advantages over traditional treatments in prevention of gastroesophageal variceal bleeding in patients with cirrhotic portal ***:This review classified and summarized the promising drugs,which prevent gastroesophageal variceal bleeding by targeting specific markers of pathogenesis of portal hypertension,demonstrating the significance of using the precision medicine strategy to discover and develop promising drugs for the primary prevention of gastroesophageal variceal bleeding in patients with cirrhotic portal hypertension.

关键词： Cirrhotic portal hypertension Target drug Primary prevention Bleeding

Controlling hydrogenation of C=C and C=O bonds in cinnamaldehyde using Pt_(1)/Ni and Pt_(1)/Co single-atom alloy catalysts

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第6期43卷 2859-2868页

作者： Huan-Shi Lan Yi-Da yang Qing-Di Sun Hao Zhang Ying Zhang Qian He Ran Chen Guo-Yi Bai Xiao-Hui He hong-Bing ji School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China Key Laboratory of Bioinorganicand Synthetic Chemistry of Ministry of Education Fine Chemical Industry Research InstituteSchool of ChemistryIGCMESun Yat-sen UniversityGuangzhou510275China UBFC CNRSENSMMFEMTO-ST Institute25030 Besancon CEDEXFrance College of Chemistry and Materials Science Hebei UniversityBaoding 071002China State Key Laboratory Breeding Base of Green-Chemical Synthesis Technology Institute of Green Petroleum Processing and Light Hydrocarbon ConversionCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou 310014China

Selective hydrogenation of C=C and C=O bonds in cinnamaldehyde(CAL)to produce desired products is a challenging task due to the complex conjugate system of the two unsaturated functional *** this study,a simple ball milling method is presented for synthesizing Pt-based single-atom alloy catalysts(SAAs)that can function as a control switch for the selective hydrogenation of CAL into highly valuable products.

关键词： alloy hydrogenation conjugate

Cr^(3+) activated Na_(3)RESi_(3)O_(9)(RE=Y,Lu,Sc) silicate broadband near-infrared phosphors for luminescence towards NIR-Ⅱ region via a multi-site occupancy strategy

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第8期42卷 1447-1457,I0002页

作者： jiantong Wang Changshuai Gong Sihan yang Qi Zhu Xuejiao Wang ji-Guang Li College of Chemistry and Materials Engineering Bohai UniversityJinzhou121007China Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China Research Center for Electronic and Optical Materials National Institute for Materials ScienceTsukubaIbaraki 305-0044Japan

Phosphor-converted near-infrared light-emitting diodes(NIR pc-LEDs) are finding applications in various fields including food quality analysis,biomedical imaging,night vision,and *** crucial factor in the development of NIR pc-LEDs devices lies in the advancement of high-performance broadband NIR phosphors,In this work,novel Cr^(3+)-activated silicate phosphors NaRESi_(3)O_(9)(RE=Y,Lu,Sc) are *** silicate has a special 3D network structure in which RE has four different sites,forming four octahedrons and providing suitable occupation sites for Cr^(3+).The phosphors demonstrate a wide emission spectrum ranging from 750 to 1450 nm when excited by light at 468 *** full width at half maximum(FWHM),which benefits from the presence of Cr^(3+)ions occupying multiple sites,is measured to be 203 ***,the strongest emission peak is observed at a longer wavelength of 984 nm compared to most other systems activated by Cr^(3+).The Na_(3)ScSi_(3)O_(9) lattice provides a weak crystal field(Dq/B=1.97) and weak phonon-photon coupling for Cr^(3+),and the integrated emission intensity of Na_(3)ScSi_(3)O_(9):0,03Cr^(3+)is 4.66 times stronger than that of Na_(3)YSi_(3)O_(9):0.03Cr^(3+).

关键词： Rare earths Broadband near-infrared Silicate Photoluminescence Cr^(3+)

Atomic tracking of thermally-driven structural evolution in 2D crystals:Case of NbSe_(2)

在线全文

学校读者我要写书评

暂无评论

InfoMat 2024年第2期6卷 90-98页

作者： Baofei Hou Teng Zhang Tingting Wang hongyan ji Huixia yang Liangguang jia Xu Han jingsi Qiao Yu Zhang Liwei Liu hong-Jun Gao Yeliang Wang School of Integrated Circuits and Electronics&yangtze Delta Region Academy Beijing Institute of TechnologyBeijingthe People's Republic of China Institute of Physics Chinese Academy of SciencesBeijingthe People's Republic of China

Advanced atomic tracking techniques play a critical role in characterizing structural evolution,elucidating fundamental mechanisms of exotic phenomena and tailoring delicate *** driven structural modulation in 2D crystals,such as the charge density wave(CDW),often leads to intriguing quantum properties,making them a valuable platform for exploring fundamental physics and potential device ***,despite their significance,experimental studies addressing atomic tracking of thermally-driven structural evolution in 2D crystals have been ***,we utilize high-accuracy variable-temperature atomic tracking measurements with scanning tunneling microscopy(STM)to directly observe a series of structural transitions in a model 2D crystal,namely NbSe_(2).With the atomic tracking technique,we confirm the existence of the universal thermally-driven CDW transition hysteresis between the heating and cooling *** transition hysteresis,characterized by a constant temperature offset,represents a new phenomenon of structural *** findings provide a feasible method to track CDW transitions at the atomic scale in 2D crystals,significantly contributing to a better understanding and the potential modulation of these materials'functions in nanodevices.

关键词： 2D crystal atomic tracking technique structural evolution temperature hysteresis

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

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

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

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

Research progress toward the influence of mosquito salivary proteins on the transmission of mosquito-borne viruses

在线全文

学校读者我要写书评

暂无评论

Insect Science 2024年第3期31卷 663-673页

作者： Zhao-yang Wang Kai-Xiao Nie ji-Chen Niu Gong Cheng Tsinghua University-Peking University Joint Center for Life Sciences School of MedicineTsinghua UniversityBejingChina Institute of Infectious Diseases Shenzhen Bay LaboratoryShenzhenGuangdongChina Department of Pathogen Biology School of Basic MedicineShandong First Medical University&Shandong Academy of Medical SciencesJinanChina

Mosquito-borne viruses(MBVs)are a large class of viruses transmitted mainly through mosquito bites,including dengue virus,Zika virus,Japanese encephalitis virus,West Nile virus,and chikungunya virus,which pose a major threat to the health of people around the *** global warming and extended human activities,the incidence of many MBVs has increased *** saliva contains a variety of bioactive protein *** not only enable blood feeding but also play a crucial role in regulating local infection at the bite site and the remote dissemination of MBVs as well as in remodeling the innate and adaptive immune responses of host ***,we review the physiological functions of mosquito salivary proteins(MSPs)in detail,the influence and the underlying mechanism of MSPs on the transmission of MBVs,and the current progress and issues that urgently need to be addressed in the research and development of MSP-based MBV transmission blocking vaccines.

关键词： immune response mosquito-borne virus mosquito salivary protein saliva vaccine transmission