检索结果-南通市图书馆

Highly Improved Creep Resistance in Polypropylene Through Thermally Reduced Graphene Oxide and Its Creep Lifetime Prediction

引用

Chinese Journal of Polymer Science 2024年第2期42卷 256-266,I0010页

作者： can-can Zhang jun-Long Yang Ya-Jiang Huang Guang-Xian Li College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering of ChinaSichuan UniversityChengdu610065China

Polypropylene(PP) exhibits suboptimal creep resistance due to the presence of methyl groups on its main chain, leading to irregular chain segment distribution, diminished inter-chain interaction, and crystallinity. This structural feature causes chain slippage in PP under stress,significantly constraining its service lifetime. In this study, thermally reduced graphene oxide(TrGO) nanosheets were incorporated into the PP matrix, yielding a nanocomposite with exceptional creep resistance performance. Results demonstrated that at a stress of 25 MPa, a 2.0 wt% TrGO content could enhance the creep failure lifetime of PP by 21.5 times compared to neat PP. Rheology, transmission electron microscopy(TEM),and scanning electron microscopy(SEM) characterization techniques were employed to analyze the mechanism of TrGO's influence on PP's creep behavior. It was observed that when TrGO content exceeded 1.0 wt%, an effective particle network structure formed within the PP matrix. This homogeneously dispersed TrGO-formed particle network structure restricted the migration and rearrangement of PP molecular chains, enabling prolonged stress resistance without structural failure. By combining the time-strain superposition method with the critical failure strain as a criterion, generalized creep compliance curves for PP and its composites were established, facilitating the prediction of material creep failure lifetimes, with a strong agreement between experimental and predicted lifetime values. This research proposes a novel strategy aimed at developing polypropylene materials and products with enhanced long-term stability and durability, thus extending service life, reducing failure risk, and broadening their potential across various application domains.

关键词： Thermally reduced graphene oxide Polypropylene Creep failure and lifetime prediction

来源：

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

Stereochemical editing:Catalytic racemization of secondary alcohols and amines

引用

Chinese Chemical Letters 2024年第5期35卷 17-31页

作者： jun Zhang Zhiyao Zheng can Zhu Department of Chemistry Fudan UniversityShanghai 200438China Department of Organic Chemistry Arrhenius LaboratoryStockholm UniversityStockholm 10691Sweden

Chiral alcohols and amines are important structural units widely existing in pharmaceuticals,agrochemicals,and food *** kinetic resolution(DKR)is an efficient strategy to deliver optically active alcohols and amines from their *** the development of DKR method,racemization catalyst plays as a crucial element with the requirement of compatibility with the kinetic resolution(KR)*** this paper,recent advance in the catalytic racemization of secondary alcohols and amines is summarized based on different types of racemizing intermediates,which are redox racemization via ketone/imine intermediates,racemization via radical intermediates,and racemization via carbocation *** racemization of secondary alcohols and amines is also enclosed.

关键词： Racemization Secondary alcohols Amines Kinetic resolution Dynamic kinetic resolution

来源：

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

Highly Hydrolysis-Resistant Polyimide Fibers Prepared by Thermal Crosslinking with Inherent Carboxyl Groups

引用

Chinese Journal of Polymer Science 2024年第2期42卷 247-255,I0010页

Easy hydrolysis in alkaline environments limits the use of polyimide fibers in environmental protection. The hydrolysis resistance levels of polyimide fibers can be improved by crosslinking of the macromolecular chains. In this work, crosslinked polyimide fibers(CPI fibers) were produced by intrinsic carboxyl decarboxylation for the first time. The thermal stability of the polyimide fibers containing the intrinsic carboxyl groups(PIC fibers) was studied, and the temperature of the decarboxylation-crosslinking reaction was determined to be 450 ℃. The PIC fibers were hotdrawn to initiate thermal crosslinking of the carboxyl groups and molecular chain orientation at high temperature. The CPI fibers had high tensile strengths(0.72-1.46 GPa) and compressive strengths(401-604 MPa). The oriented macromolecules and chemically crosslinked structure improved the tightness of the molecular chains and endowed the CPI fibers with excellent hydrolytic resistance. The CPI-50 fiber did not dissolve in a 0.5 wt% NaOH solution during heating at 90 ℃ for 10 h, and the tensile strength retention reached 87% when treated in 0.5 wt% NaOH solutions at 90 ℃ for 1 h, providing a guarantee for its application in alkaline corrosive environments.

关键词： Polyimide Carboxyl group Crosslinking Hydrolysis-resistance

来源：

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

Alkyl chain modulation of asymmetric hexacyclic fused acceptor synergistically with wide bandgap third component for high efficiency ternary organic solar cells

引用

International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1713-1719页

作者： Shufang Li Huilan Guan can Zhu Chaoyuan Sun Qingya Wei jun Yuan Yingping Zou College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China Institute of Carbon Neutrality and New Energy School of Electronics and InformationHangzhou Dianzi UniversityHangzhou 310018China

Herein,two asymmetric hexacyclic fused small molecule acceptors(SMAs),namely BP4F-HU and BP4F-UU,were *** elongated outside chains in the BP4F-UU molecule played a crucial role in optimizing the morphology of blend film,thereby improving charge mobility and reducing energy loss within the corresponding ***,the PM6:BP4F-UU device exhibited a higher open-circuit voltage(V_(oc))of 0.878 V compared to the PM6:BP4F-HU device with a V_(oc)of 0.863 ***,a new wide bandgap SMA named BTP-TA was designed and synthesized as the third component to the PM6:BP4F-UU host binary devices,which showed an ideal complementary absorption spectrum in PM6:BP4F-UU *** addition,BTP-TA can achieve efficient intermolecular energy transfer to BP4F-UU by fluorescence resonance energy transfer(FRET)pathway,due to the good overlap between the photoluminescence(PL)spectrum of BTP-TA and the absorption region of ***,ternary devices with 15wt%BTP-TA exhibits broader photon utilization,optimal blend morphology,and reduced charge recombination compared to the corresponding binary ***,PM6:BP4F-UU:BTP-TA ternary device achieved an optimal power conversion efficiency(PCE)of 17.83%with simultaneously increased V_(oc)of 0.905 V,short-circuit current density(J_(sc))of 26.14 mA/cm^(2),and fill factor(FF)of 75.38%.

关键词： asymmetric hexacyclic acceptor outside chain wide bandgap acceptor ternary organic solar cells

来源：

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

Paeoniflorin,the Main Monomer Component of Paeonia lactiflora,Exhibits Anti-inflammatory Properties in Osteoarthritis Synovial Inflammation

引用

Chinese Journal of Integrative Medicine 2024年第5期30卷 433-442页

作者： CHEN Pu ZHOU jun ruan An-min MA Yu-feng WANG Qing-fu Department of Orthopaedic Surgery Beijing University of Chinese Medicine Third Affiliated HospitalBeijing 100029China Department of Orthopaedic Surgery Guangdong Provincial Hospital of Chinese MedicineGuangzhou 510120China Department of Orthopaedic Surgery Beijing Longfu HospitalBeijing 100010China

Objective:To explore the mechanism of paeoniflorin(PF)on osteoarthritis(OA)synovial inflammation from network pharmacology to experimental ***:Targets of OA were constructed by detecting the database of network database platforms(Therapeutic Target database,Drug Bank and Gene Cards),and the targets of PF were constructed by Pub Chem and Herbal Ingredients'Targets *** Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis of these co-targeted genes were conducted via Database for Annotation,Visualization,and Integrated Discovery(DAVID)database,and protein-protein interaction(PPI)networks were conducted via the search tool for the retrieval of interacting genes(STRING)*** counting kit-8(CCK-8)assay was performed to assess the potential toxicity of PF on human OA fibroblast-like synoviocytes(FLS),quantitative real-time polymerase chain reaction(q PCR),enzyme-linked immunosorbent assay(ELISA)and Western blot were used to verify the potential mechanism of PF in synovial ***:Twenty-six co-targeted genes were *** enrichment results showed that these co-targeted genes were most likely localized in the cytoplasm,and the biological processes mainly involved'cellular response to hypoxia''lipopolysaccharide(LPS)-mediated signaling pathway'and'positive regulation of gene expression'.KEGG pathway analysis indicated that these co-targeted genes may function through pathways associated with'hypoxia-inducible factor-1(HIF-1)signaling pathway'and'tumornecrosis factor(TNF)signaling pathway'.The PPI network showed that the top 3 hub genes were TP53,TNF,and *** docking results showed that PF was well docking with ***-8 showed no potential toxicity of 10,20 and 50μmol/L PF on human OA *** PF significantly decreased the expression levels of interleukin-1β,interleukin-6,TNF-αmatrix metalloproteinase 13(MMP13),and a disintegrin and metalloproteinase with thrombospondin motifs 5(ADAMTS5)and TNF

关键词： paeoniflorin osteoarthritis synovial inflammation tumor necrosis factor-α network pharmacology Paeonia lactiflora

来源：

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

Short-term effects of cupping and scraping therapy for chronic nonspecific low-back pain:A prospective,multicenter randomized trial

引用

Journal of Integrative Medicine 2024年第1期22卷 39-45页

作者： jun-yan He Xiao-yu Tu Zi-fei Yin Hui Mu Ming-jun Luo Xing-yu Chen Wei-bin Cai Xue Zhao can Peng Fan-fu Fang can Lü Bai Li School of Traditional Chinese Medicine Naval Medical UniversityShanghai 200433China Department of Rehabilitation Medicine and Physiotherapy the First Affiliated Hospital of Naval Medical UniversityShanghai 200433China Department of Rehabilitation Medicine and Training PLA 458 HospitalGuangzhou 510602Guangdong ProvinceChina No.3 Ward of Acupuncture Rehabilitation Department Guangdong Second Traditional Chinese Medicine HospitalGuangzhou 510095Guangdong ProvinceChina

Background As one of the most common musculoskeletal ailments,chronic nonspecific low-back pain(CNLBP)causes persistent disability and substantial medical *** evidence shows that the incidence rate of CNLBP in young and middle-aged people who are demanded rapidly recovery and social contribution is *** guidelines indicate a reduced role for medicines in the management of *** The present study investigates the short-term effects of cupping and scraping therapy using a medicated balm,compared to nonsteroidal anti-inflammatory drug(NSAID)with a capsaicin plaster,in the treatment of ***,setting,participants and interventions We designed a prospective multicenter randomized clinical trial enrolling patients from January 1,2022 to December 31,2022.A total of 156 patients with CNLBP were randomized into two parallel *** sodium-sustained release tablets were administered orally to participants in the control group for one week while a capsaicin plaster was applied *** in the test group were treated with cupping and scraping using a medical device and medicated *** outcome measures Primary outcome was pain recorded using the visual analogue scale(VAS).Two secondary outcomes were recorded using the Japanese Orthopedic Association low-back pain scale(JOA)and the traditional Chinese medicine(TCM)syndrome integral scale(TCMS)as assessment *** Between baseline and postintervention,all changes in outcome metric scales were statistically significant(Pcantly greater treatment effect in all outcome variables,as indicated by lower VAS and TCMS scores and higher JOA scores,after the one-week intervention period(P<0.001).Further,according to the findings of multivariate linear regression analysis,the participants’pain(VAS score)was related to their marital status,age,smoking habits and body mass *** adverse r

关键词： Chronic nonspecific low-back pain Traditional Chinese medicine Cupping and scraping therapy

来源：

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

Cholecystokinin and cholecystokinin-A receptor: An attractive treatment strategy for biliary dyskinesia?

引用

World Journal of Gastroenterology 2024年第3期30卷 283-285页

作者： jun Chang Yan Liu Ting-can Jiang Lan Zhao Jian-Wei Liu Tianjin Institute of Acupuncture and Moxibustion The First Teaching Hospital of Tianjin University of Traditional Chinese MedicineTianjin 300381China Department of Gastroenterology Tianjin Hospital of Integrated Traditional Chinese and Western Medicine Nankai HospitalTianjin 300100China State Key Laboratory of Component-Based Chinese Medicine Tianjin University of Traditional Chinese MedicineTianjin 301617China School of Integrative Medicine Tianjin University of Traditional Chinese MedicineTianjin 301617China

Biliary dyskinesia is a relatively common gastrointestinal disease that is increas-ing in incidence as living standards ***,its underlying pathogenesis remains unclear,hindering the development of therapeutic ***,“Expression and functional study of cholecystokinin-A receptors on the interstitial Cajal-like cells of the guinea pig common bile duct”demonstrated that cholecystokinin(CCK)regulates the contractile function of the common bile duct through interaction with the CCK-A receptor in interstitial Cajal-like cells,contributing to improving the academic understanding of biliary tract dynamics and providing emerging directions for the pathogenesis and clinical management of biliary *** letter provides a brief overview of the role of CCK and CCK-A receptors in biliary dyskinesia from the perspective of animal experiments and clinical studies,and discusses prospects and challenges for the clinical application of CCK and CCK-A receptors as potential therapeutic targets.

关键词： Cholecystokinin Cholecystokinin-A receptor Biliary dyskinesia Interstitial Cajal-like cell Therapeutic target

来源：

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

Spray pyrolysis-derived W-doped MoSe2/rGO paper-like microspheres:optimization of microstructure and mesostructure for enhanced lithium storage

引用

Rare Metals 2024年第7期43卷 3019-3031页

作者： Wei Wang jun-Yu Chen Jie Ouyang Hong Yin Ao-Jie Li Liang Chen jun-Lin Huang Yu-can Zhu Gang-Yong Li Zhao-Hui Hou Key Laboratory of Hunan Province for Advanced Carbon-based Functional Materials Hunan Institute of Science and Technology School of Chemistry and Chemical Engineering Hunan Institute of Science and Technology Hunan Province Key Laboratory of Materials Surface & Interface Science and Technology Material Science and Engineering SchoolCentral South University of Forestry and Technology International Iberian Nanotechnology Laboratory (INL)

Two-dimensional MoSe2is a promising candidate for lithium-ion battery ***,its conductivity and lithium storage volumetric effect still need to be *** this work,W-doped MoSe2/rGO paper-like microspheres are successfully prepared through ultrasonic spray pyrolysis,achieving optimization at both the microstructure and mesostructure to enhance the lithium storage performance of the ***,by utilizing the similar two-dimensional structure between MoSe2and rGO,self-assembly is achieved through spray pyrolysis,resulting in a well-defined van der Waals heterostructure at the interface on the microscale,enhancing the electron and ion transfer capability of the ***,the mesoscale paper-like microsphere morphology provides additional volume expansion buffering ***,W-doping not only increases the interlayer spacing of MoSe2（0.73 nm）,thereby reducing the diffusion resistance of Li+,but also allow for the modulation of the energy band structure of the *** functional theory（DFT） calculations confirm that W-doped MoSe2/rGO exhibits the narrowest bandgap（0.892 eV）.Therefore,the composite demonstrates excellent lithium storage performance,maintaining a specific capacity of 732.9 mAh·g-1after 300 cycles at a current density of 1 A·g-1.

关键词： Molybdenum selenide Heterostructure Microspheres Li-ion batteries Kinetics

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Evaluation of dry eye disease symptomatology and mental health status among patients with different COVID-19 statuses

引用

International Journal of Ophthalmology(English edition) 2024年第5期17卷 822-830页

作者： Fang ruan Wen-jun Kong Qian Fan Hong-Wei Dong Wei Zhang Wen-Bin Wei Ying Jie Department of Ophthalmology Beijing You’an HospitalCapital Medical UniversityBeijing Infectious Eye Disease Diagnosis and Treatment CenterBeijing 100069China Beijing Tongren Eye Center Beijing Tongren HospitalCapital Medical UniversityBeijing Institute of OphthalmologyBeijing Ophthalmology and Visual Sciences Key LabBeijing 100730China Tianjin Eye Hospital Tianjin Key Lab of Ophthalmology and Visual ScienceTianjin Eye InstituteNankai University Affiliated Eye HospitalNankai University Eye InstituteNankai UniversityClinical College of OphthalmologyTianjin Medical UniversityTianjin 300020China

AIM:To evaluate dry eye disease(DED)symptomatology and mental health status in different COVID-19 ***:A cross-sectional observational design was *** 123 eligible adults(46.34%of men,age range,18-59y)with COVID-19 included in the study from August to November,*** Surface Disease Index(OSDI),Five-item Dry Eye Questionnaire(DEQ-5),Hospital Anxiety and Depression Scale(HADS),and Pittsburgh Sleep Quality Index(PSQI)were used in this ***:OSDI scores were 6.82(1.25,15.91)in asymptomatic carriers,7.35(2.50,18.38)in mild cases,and 16.67(4.43,28.04)in recurrent cases,with 30.00%,35.56%,and 57.89%,respectively evaluated as having DED symptoms(χ2=7.049,P=0.029).DEQ-5 score varied from 2.00(0,6.00)in asymptomatic carriers,3.00(0,8.00)in mild cases,and 8.00(5.00,10.00)in recurrent cases,with 27.50%,33.33%,and 55.26%,respectively assessed as having DED symptoms(χ2=8.532,P=0.014).The prevalence of clinical anxiety(50.00%)and depression(47.37%)symptoms were also significantly higher in patients with recurrent infection(χ2=24.541,P<0.001;χ2=30.871,P<0.001).Recurrent infection was a risk factor for high OSDI scores[odds ratio,2.562;95%confidence interval(CI),1.631-7.979;P=0.033]and DEQ-5 scores(odds ratio,3.353;95%CI,1.038-8.834;P=0.043),whereas having a fixed occupation was a protective factor for OSDI scores(odds ratio,0.088;95%CI,0.022-0.360;P=0.001)and DEQ-5 scores(odds ratio,0.126;95%CI,0.039-0.405;P=0.001).CONCLUSION:Patients with recurrent COVID-19 have more severe symptoms of DED,anxiety,and depression.

关键词： COVID-19 dry eye disease recurrent infection mental health

来源：

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

Highly Thermally Conductive Polydimethylsiloxane Composites with Controllable 3D GO@f-CNTs Networks via Self-sacrificing Template Method

引用

Chinese Journal of Polymer Science 2024年第7期42卷 897-906,I0005页

作者： Shuang-Shuang Wang Dian-Ying Feng Zhi-Ming Zhang Xia Liu Kun-Peng ruan Yong-Qiang Guo jun-Wei Gu Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an710072China Shandong Institute of Nonmetallic Materials Jinan250031China Queen Mary University of London Engineering School Northwestern Polytechnical UniversityXi’an710072China

Constructing controllable thermal conduction networks is the key to efficiently improve thermal conductivities of polymer *** this work,graphite oxide(GO)and functionalized carbon nanotubes(f-CNTs)are combined to prepare“Line-Plane”-like hetero-structured thermally conductive GO@f-CNTs fillers,which are then performed to construct controllable 3D GO@f-CNTs thermal conduction networks via selfsacrificing template method based on oxalic ***,thermally conductive GO@f-CNTs/polydimethylsiloxane(PDMS)composites are fabricated via casting *** the size of oxalic acid is 0.24 mm and the volume fraction of GO@f-CNTs is 60 vol%,GO@f-CNTs/PDMS composites present the optimal thermal conductivity coefficient(λ,4.00 W·m^(-1)·K^(-1)),about 20 times that of theλof neat PDMS(0.20 W·m^(-1)·K^(-1)),also much higher than theλ(2.44 W·m^(-1)·K^(-1))of GO/f-CNTs/PDMS composites with the same amount of randomly dispersed ***,the obtained GO@f-CNTs/PDMS composites have excellent thermal stability,whoseλdeviation is only about 3%after 500 thermal cycles(20-200℃).

关键词： Polydimethylsiloxane Hetero-structured thermally conductive fillers Self-sacrificing template Thermal conduction networks

来源：

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

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：