检索结果-南通市图书馆

Molecular Chain Flexibility and Dielectric Loss at High-Frequency:Impact of Ester Bond Arrangement in Poly(ester imide)s

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8期42卷 1122-1133页

作者： Ya-Dong Li Hong Li Lu-Kun Feng Feng bao Ming-Liang Wang Cai-Zhen zhu Zhao-Hui Zheng Xiao-Bin Ding Jian Xu Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100081China Institute of Low-Dimensional Materials Genome Initiative College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060China

The evolution of high-frequency communication has accentuated the significance of controlling dielectric properties in polymer ***,it has been theorized that rigid molecular chains lead to lower dielectric ***,the validity of this proposition at high frequencies remains *** scrutinize the correlation between chain flexibility and dielectric properties,we synthesized six poly(ester imide)s(PEIs)with systematically varied molecular chain flexibilities by modifying the ester's substitution on the aromatic *** introduction of ester bonds bestowed all PEI films with a low dielectric dissipation factor(D_(f)),ranging from 0.0021 to 0.0038 at 10 GHz in dry *** dry D_(f)displayed a pattern consistent with volume polarizability(P/V).Unexpectedly,PI-mmm-T,featu ring the most flexible molecular chain,exhibited the lowest dielectric loss under both dry(0.0021@10 GHz)and hygroscopic(0.0029@10 GHz)***,the observed increase in D_(f)after humidity absorption suggests that the high dielectric loss of PEI in applications may be attributed to its hygroscopic *** simulations and characterization of the aggregation structure revealed that the smaller cavities within flexible molecular chains,after close stacking,impede the entry of water *** sacrificing high-temperature resistance,the precursor exhibited enhanced solubility properties and could be processed into high-quality *** research unveils new insights into the relationship between flexibility and highfrequency dielectric loss,offering innovative perspectives on synthesizing aromatic polymers with exceptional dielectric properties.

关键词： 5G communications Poly(ester imide)s Molecular chain flexibility Dielectric properties Humidity absorption

Functional role of circRNA CHRC through miR-431-5p/KLF15 signaling axis in the progression of heart failure

在线全文

学校读者我要写书评

暂无评论

Journal of Genetics and Genomics 2024年第8期51卷 844-854页

作者： Yi Hu Huaming Cao Jie sheng Yizhuo Sun Yuping zhu Qin Lin Na Yi Siyu He Luying Peng Li Li State Key Laboratory of Cardiology and Medical Innovation Center Shanghai East HospitalTongji University School of MedicineShanghai 200120China Shanghai Arrhythmias Research Center Shanghai East HospitalTongji University School of MedicineShanghai 200120China Laboratory of Molecular Genetics and Stem Cell Differentiation Tongji University School of MedicineShanghai 200120China Department of Cardiology Shanghai Shibei HospitalShanghai 200435China Research Units of Origin and Regulation of Heart Rhythm Chinese Academy of Medical SciencesShanghai 200120China

Pathological myocardial hypertrophy is a common early clinical manifestation of heart failure,with noncoding RNAs exerting regulatory ***,the molecular function of circular RNAs(circRNAs)in the progression from cardiac hypertrophy to heart failure remains *** uncover functional circRNAs and identify the core circRNA signaling pathway in heart failure,we construct a global triple network(microRNA,circRNA,and mRNA)based on the competitive endogenous RNA(ceRNA)*** observe that cardiac hypertrophy-related circRNA(circRNA CHRC),within the ceRNA network,is down-regulated in both transverse aortic constriction mice and Ang-II--treated primary mouse *** circRNA CHRC increases cross-sectional cell area,atrial natriuretic peptide,andβ-myosin heavy chain levels in primary mouse *** screening shows that circRNA CHRC targets the miR-431-5p/KLF15 axis implicated in heart failure progression in vivo and in *** with anti-Ago2-RNA confirms the interaction between circRNA CHRC and miR-431-5p,while miR-431-5p mimics reverse Klf15 activation caused by circRNA CHRC *** summary,circRNA CHRC attenuates cardiac hypertrophy via sponging miR-431-5p to maintain the normal level of Klf15 expression.

关键词： circRNA CHRC Heart failure CeRNA miR-431-4p KIf15

C-F insertion reaction sheds new light on the construction of fluorinated compounds

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 Chemical Letters 2024年第8期35卷 163-169页

作者： Dong-sheng Deng Su-Qin Tang Yong-Tu Yuan Ding-Xiong Xie Zhi-Yuan zhu Yue-Mei Huang Yun-Lin Liu Henan Key Laboratory of Function-Oriented Porous Materials and College of Chemistry and Chemical EngineeringLuoyang Normal UniversityLuoyang 471934China School of Chemistry and Chemical Engineering Guangzhou UniversityGuangzhou 510006China Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

The atom-economical C-F insertion chemistry is emerged as a promising technology for the synthesis of various fluorinated scaffolds,which have wide applications both in the academic and the industrial *** past three years have witnessed rapid developments in this *** highlight provides an overview on the evolution according to the fluorinating agents used.

关键词： C-F insertion Benzyl fluoride Acyl fluoride gem-Difluorocyclopropane Fluorinated scaffold

Spin transport of half-metal Mn_(2)X_(3) with high Curie temperature:An ideal giant magnetoresistance device from electrical and thermal drives

在线全文

学校读者我要写书评

暂无评论

Frontiers of physics 2024年第4期19卷 125-135页

作者： Bin Liu Xiaolin Zhang Jingxian Xiong Xiuyang Pang sheng Liu Zixin Yang Qiang Yu Honggen Li Sicong zhu Jian Wu Hubei Province Key Laboratory of Systems Science in Metallurgical Process The State Key Laboratory for Refractories and MetallurgyCollaborative Innovation Center for Advanced SteelsInternational Research Institute for Steel TechnologyWuhan University of Science and TechnologyWuhan 430081China Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education and School of Physical and Technology Wuhan UniversityWuhan 430072China College of Advanced Interdisciplinary Studies Nanhu Laser LaboratoryNational University of Defense TechnologyChangsha 410073China Department of Mechanical Engineering National University of SingaporeSingapore 117575Singapore i-Lab&Key Laboratory of Nanodevices and Applications&Key Laboratory of Nanophotonic Materials and Devices Suzhou Institute of Nano-Tech and NanoBionicsChinese Academy of SciencesSuzhou 215123China Institute of Optical Science and Technology School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China

Currently,magnetic storage devices are encountering the problem of achieving lightweight and high integration in mobile computing devices during the information *** a result,there is a growing urgency for twodimensional half-metallic materials with a high Curie temperature(TC).This study presents a theoretical investigation of the fundamental electromagnetic properties of the monolayer hexagonal lattice of Mn_(2)X_(3)(X=S,Se,Te).Additionally,the potential application of Mn_(2)X_(3) as magneto-resistive components is *** three of them fall into the category of ferromagnetic *** particular,the Monte Carlo simulations indicate that the TC of Mn2S3 reachs 381 K,noticeably greater than room *** findings present notable advantages for the application of Mn2S3 in spintronic ***,a prominent spin filtering effect is apparent when employing non-equilibrium Green’s function simulations to examine the transport *** resulting current magnitude is approximately 2×10^(4) nA,while the peak gigantic magnetoresistance exhibits a substantial value of 8.36×10^(16)%.It is noteworthy that the device demonstrates a substantial spin Seebeck effect when the temperature differential between the electrodes is *** brief,Mn_(2)X_(3) exhibits outstanding features as a highTC half-metal,exhibiting exceptional capabilities in electrical and thermal drives spin ***,it holds great potential for usage in spintronics applications.

关键词： half-metals Mn_(2)X_(3) high Curie temperature electrical and thermal GMR

Design of bifunctional single-atom catalysts NiSA/ZIF-300 for CO_(2) conversion by ligand regulation strategy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第5期17卷 3827-3834页

作者： Wengang Fu Yapei Yun Hongting sheng Xiaokang Liu Tao Ding Shuxian Hu Tao Yao Binghui Ge Yuanxin Du Didier Astruc Manzhou zhu Department of Chemistry and Centre for Atomic Engineering of Advanced Materials Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationCollege of Materials Science and EngineeringInstitutes of Physical Science and Information Technology and Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized MaterialsAnhui UniversityHefei 230601China Universitéde Bordeaux ISMUMR CNRS N°5255351 Cours de La Libération33405 Talence CedexFrance National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026China Department of Physics University of Science and Technology BeijingBeijing 100083China Anhui Tongyuan Environment Energy Saving Co. LtdHefei 230041China

Carbon-supported noble-metal-free single-atom catalysts(SACs)have aroused widespread interest due to their green chemistry aspects and excellent ***,we propose a“ligand regulation strategy”and achieve the successful fabrication of bifunctional SAC/MOF(MOF=metal-organic framework)nanocomposite(abbreviated NiSA/ZIF-300;ZIF=ZIF-8)with exceptional catalytic performance and *** designed NiSA/ZIF-300 has a planar interfacial structure with the Ni atom,involving one S and three N atoms bonded to Ni(Ⅱ),fabricated by controllable pyrolysis of volatile Ni-S *** CO_(2) cycloaddition to styrene epoxide,NiSA/ZIF-300 exhibits ultrahigh activity(turnover number(TON)=1.18×105;turnover frequency(TOF)=9830 molSC·mol_(Ni)^(-1)·h^(-1);SC=styrene carbonate)and durability at 70℃ under 1 atm CO_(2) pressure,which is much superior to Ni complex/ZIF,NiNP/ZIF-300,and most reported *** study offers a simple method of bifunctional SAC/MOF nanocomposite fabrication and usage,and provides guidance for the precise design of additional original SACs with unique catalytic properties.

关键词： single atom catalyst bifunctional CO_(2)conversion cycloaddition

Hepatocyte growth factor promotes retinal pigment epithelium cell activity through MET/AKT signaling pathway

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5期17卷 806-814页

作者： Si-Rui Zhou Yu-sheng zhu Wen-Ting Yuan Xiao-Yan Pan Tong Wang Xiao-Dong Chen Faculty of Life Sciences and Medicine Northwest UniversityXi’an 710069Shaanxi ProvinceChina First Affiliated Hospital of Northwest University Northwest UniversityXi’an 710069Shaanxi ProvinceChina Department of Ophthalmology Xi’an No.1 HospitalXi’an 710002Shaanxi ProvinceChina Shaanxi Institute of Ophthalmology Shaanxi Provincial Key Lab of OphthalmologyClinical Research Center for Ophthalmology Diseases of Shaanxi ProvinceXi’an 710002Shaanxi ProvinceChina

AIM:To explore the effects of hepatocyte growth factor(HGF)on retinal pigment epithelium(RPE)cell ***:The human adult retinal pigment epithelial cell line-19(ARPE-19)were treated by HGF or mesenchymalepithelial transition factor(MET)inhibitor SU11274 in *** viability was detected by a Cell Counting Kit-8 *** proliferation and motility was detected by a bromodeoxyuridine incorporation assay and a wound healing assay,*** expression levels of MET,phosphorylated MET,protein kinase B(AKT),and phosphorylated AKT proteins were determined by Western blot *** MET and phosphorylated MET proteins were also determined by immunofluorescence ***:HGF increased ARPE-19 cells’viability,proliferation and migration,and induced an increase of phosphorylated MET and phosphorylated AKT ***11274 significantly reduced cell viability,proliferation,and migration and decreased the expression of MET and AKT ***11274 suppressed HGF-induced increase of viability,proliferation,and migration in ARPE-19 ***,SU11274 also blocked HGF-induced phosphorylation of MET and AKT ***:HGF enhances cellular viability,proliferation,and migration in RPE cells through the MET/AKT signaling pathway,whereas this enhancement is suppressed by the MET inhibitor ***-induced MET/AKT signaling might be a vital contributor of RPE cells survival.

关键词： hepatocyte growth factor mesenchymal epithelial transition factor SU11274 retinal pigment epithelial cells

Revealing the Structure-Property Difference of Natural Rubber Prepared by Different Methods: Protein and Gel Content are Key Factors

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4期42卷 457-467页

作者： Shao-Qi Huang Jun-Qi Zhang Yong zhu Ling-Min Kong Lu-sheng Liao Fu-Quan Zhang Zheng-Tian Xie Jin-Rong Wu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu610065China Hainan Provincial Key Laboratory of Natural Rubber Processing Agricultural Products Processing Research Institute of Chinese Academy of Tropical Agricultural SciencesZhanjiang524001China

Natural rubber (NR) is widely used in various fields including aerospace, military industry and transportation due to its superior elasticity and comprehensive mechanical properties. Nonetheless, the commercial NR prepared by different methods usually exhibits different mechanical properties, primarily due to variations in processing conditions during the conversion from latex to bulk rubber material. Consequently, this poses challenges in scientific research and industrial production of NR. In order to assess the properties of various commercially available NR and identify key structural and compositional components, this study systematically compares and analyzes four representative NR raw materials: air dried sheet (ADS), ribbed smoked sheets (RSS), constant viscidity NR (CV), and whole field latex rubber (WF). The investigation focuses on evaluating their static mechanical behavior, SIC behavior, wear resistance, and fatigue resistance. The findings indicate that protein and gel content exhibit a crucial influence on the NR properties. These constituents contribute to the formation of a high-crosslinking density region, generating a heterogeneous network structure within the rubber. This structure amplifies strains during deformation, leading to earlier and stronger strain-induced crystallization (SIC). Among the four commercial NR brands, RSS demonstrates superior overall mechanical and dynamic properties owing to its high protein and gel content. This study serves as a valuable reference for comprehending the differences in properties among various commercial NR, thereby offering guidance for the actual processing and selection of NR.

关键词： Natural rubber Processingmethod Protein Gel content Property

Persistence of charge density wave against variation of band structures in V_(x)Ti_(1−x)Se_(2)(x=0–0.1)

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第3期17卷 2129-2135页

作者： Zhanfeng Liu Tongrui Li Wen zhu Hongwei Shou Mukhtar Lawan Adam Qilong Cui Yuliang Li sheng Wang Yunbo Wu Hongen zhu Yi Liu Shuangming Chen Xiaojun Wu shengtao Cui Li Song Zhe Sun National Synchrotron Radiation Laboratory CAS Center for Excellence in NanoscienceUniversity of Science and Technology of ChinaHefei 230029China CAS Key Laboratory of Strongly-coupled Quantum Matter Physics University of Science and Technology of ChinaHefei 230026China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China School of Chemistry and Materials Sciences CAS Key Laboratory of Materials for Energy Conversionand CAS Center for Excellence in NanoscienceUniversity of Science and Technology of ChinaHefei 230026China School Zhejiang Institute of Photonelectronics Jinhua 321004China

Charge density wave(CDW)is a phenomenon that occurs in materials,accompanied by changes in their intrinsic electronic *** study of CDW and its modulation in materials holds tremendous significance in materials research,as it provides a unique approach to controlling the electronic properties of ***_(2) is a typical layered material with a CDW phase at low *** V substitution for Ti in TiSe_(2),we tuned the carrier concentration in V_(x)Ti_(1-x)Se_(2) to study how its electronic structures ***-resolved photoemission spectroscopy(ARPES)shows that the band-folding effect is sustained with the doping level up to 10%,indicating the persistence of the CDW phase,even though the band structure is strikingly different from that of the parent compound TiSe_(2).Though CDW can induce the band fold effect with a driving force from the perspective of electronic systems,our studies suggest that this behavior could be maintained by lattice distortion of the CDW phase,even if band structures deviate from the electron-driven CDW *** work provides a constraint for understanding the CDW mechanism in TiSe_(2),and highlights the role of lattice distortion in the band-folding effect.

关键词： charge density wave band structure lattice distortion

Network Pharmacology and Experimental Study of MomordicineⅠand MomordicineⅡfrom Bitter Melon Saponins in Inhibiting Fat Accumulation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2024年第5期37卷 526-530页

作者： HUANG Shi Ting LI Shang Yuan LI Xin Yu zhu Ying zhu Lin ZHANG Jia Yan ZHAO Yan sheng DAGLIA Maria XIAO Xiang BAI Juan School of Food and Biological Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina Department of Pharmacy University of Napoli FedericoⅡVia D.Montesano 4980131 NaplesItaly International Research Center for Food Nutrition and Safety Jiangsu UniversityZhenjiang 212013JiangsuChina

Bitter melon(Momordica Charania L.),a member of the Cucurbitaceae family,is widely distributed across tropical and subtropical ***,an important functional component of bitter melon,has been proven to exert hypoglycemic effects similarly to insulin,and also possesses lipid-lowering properties inhibiting preadipocyte differentiation and fat synthesis^([1]).

关键词： melon Momordica subtropical