检索结果-南通市图书馆

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

引用

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

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

Competition of Composition Fluctuation Modes in Weakly Segregated Salt-doped Symmetric Diblock Copolymers

引用

Chinese Journal of Polymer Science 2024年第9期42卷 1375-1385,I0008页

作者： Yuan-Xin Zhou Xian kong South China Advanced Institute for Soft Matter Science and Technology School of Emergent Soft MatterSouth China University of TechnologyGuangzhou510640China Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices South China University of TechnologyGuangzhou510640China

Salt-doped block copolymers have widespread applications in batteries,fuel cells,semiconductors,and various industries,where their properties crucially depend on phase separation ***,investigations into salt-doped diblock copolymers have predominantly focused on microphase separation,overlooking the segregation between ionic and polymeric *** study employs weak segregation theory to explore the interplay between phase separation dominated by the polymer-modulated mode and the salt-out-modulated mode,corresponding to microscopic and macroscopic phase separations,*** comparing diblock copolymers doped with salts to those doped with neutral solvents,we elucidate the significant role of charged species in modulating phase *** phase separation mode exhibits a transition between the polymer-modulated and salt-out-modulated modes at different *** systems doped with neutral solvents,this transition is stepwise,while in salt-ion-doped systems,it is *** a sufficiently large Flory-Huggins parameter between ions and polymers,the salt-out-modulated mode becomes dominant,promoting macrophase *** to the solvation effect of salt ions,salt-doped systems are more inclined to undergo microphase ***,we explore factors influencing the critical wavenumber of phase separation,including doping level and the Flory-Huggins parameters between two blocks and between ions and polymeric *** findings reveal that in a neutral solvent environment,these factors alter only the boundary between micro-and macro-phase separations,leaving the critical wavenumber unchanged in microphase separation ***,in a salt-doped environment,the critical wavenumber of microphase separation varies with these *** provides valuable insights into the pivotal role of electrostatics in the phase separation of salt-doped block copolymers.

关键词： Block copolymer Phase separation Field theory Salt-doped

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

Non-dimensional analysis on blast wave propagation in foam concrete:Minimum thickness to avoid stress enhancement

引用

Defence Technology（防务技术） 2024年第6期36卷 30-46页

作者： Ya Yang Xiangzhen kong Qin Fang State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing 210007JiangsuChina

Foam concrete is a prospective material in defense engineering to protect structures due to its high energy absorption capability resulted from the long plateau ***,stress enhancement rather than stress mitigation may happen when foam concrete is used as sacrificial claddings placed in the path of an incoming blast *** investigate this interesting phenomenon,a one-dimensional difference model for blast wave propagation in foam concrete is firstly proposed and numerically solved by improving the second-order Godunov *** difference model and numerical algorithm are validated against experimental results including both the stress mitigation and the stress *** difference model is then used to numerically analyze the blast wave propagation and deformation of material in which the effects of blast loads,stress-strain relation and length of foam concrete are *** particular,the concept of minimum thickness of foam concrete to avoid stress enhancement is ***,non-dimensional analysis on the minimum thickness is conducted and an empirical formula is proposed by curve-fitting the numerical data,which can provide a reference for the application of foam concrete in defense engineering.

关键词： Foam concrete Blast wave propagation Non-dimensional analysis Stress enhancement

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

Asperochones A and B,two antimicrobial aromatic polyketides from the endophytic fungus Aspergillus ***-2

引用

Chinese Chemical Letters 2024年第9期35卷 206-209页

作者： Hong Zhang Cui-Ping Li Li-Li Wang Zhuo-da Zhou Wen-Sen Li Ling-Yi kong Ming-Hua Yang Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 210009China

Two novel fungal metabolites,asperochones A and B,were obtained from an Aspergillus *** structures were determined by 1D/2D nuclear magnetic resonance(NMR)spectroscopy,high resolution electrospray ionization mass spectroscopy(HRESIMS),and single-crystal X-ray diffraction *** A possesses an intriguing skeleton bearing 5/6/6/6/7/5/5/5 octacyclic ring system,and asperochone B also exhibits an unusual carbon skeleton with five stereochiral *** structures were proposed as heterotrimeric and heterodimeric products of aromatic *** addition,asperochone A exhibited a potential anti-tuberculosis effect since it showed a moderate potency against Mycobacterium smegmatis.

关键词： Aspergillus sp. Asperochones A and B Aromatic polyketides Heterotrimeric compound Anti-tuberculosis effect Antifibrotic activity

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

Enhanced Natural Convection for Accelerating Melting of Phase Change Material in Cellular Structure through Inserting Fin

引用

Journal of Thermal Science 2024年第2期33卷 548-563页

作者： kong Dekui ZHANG Yongcun LIU Shutian State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDalian University of TechnologyDalian116024China

The design of thermal conductivity enhancers(TCE) is quite critical to overcoming the disadvantage of the poor thermal conductivity of phase change materials(PCM).The main contribution of this study is firstly to discuss how to actively enhance natural convection of the melted PCM in cellular structure by the fin formed in the structure under the condition of the same metal mass,apart from simultaneously improving heat conduction,which can boost the heat transfer ***,a tailored hybrid fin-lattice structure(HFS) as TCE is designed and fabricated by additive manufacturing(AM).A two-equation numerical method is applied to study the heat transfer of the PCM,and its feasibility is validated with the experimental *** numerical results indicate that enhanced natural convection and improved heat conduction can be obtained simultaneously when a well-designed fin is embedded into a lattice *** enhanced natural convection results in the improved melting rate and the decreased wall temperature;e.g.,the complete melting time and the wall temperature are reduced by 11.6% and 19.7%,respectively,because of the fin for metal ***,the parameters of HFS including the porosity,pore density,and fin dimension have a great impact on the heat *** enhancement effect of the fin for HFS on the melting rate of the PCM increases as the thermal conductivity of the base material *** example,when the fin is introduced into the lattice structure,the complete melting time is reduced by 24.1% for metal *** summary,this study enables us to obtain a good understanding of the mechanism of the heat transfer and provides necessary experimental data for the structural design of HFS fabricated by AM.

关键词： natural convection heat transfer enhancement phase change material additive manufacturing hybrid fin-lattice structure

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

Water quality and habitat drive phytoplankton taxonomic and functional group patterns in the Yangtze River

引用

Ecological Processes 2024年第1期13卷 144-158页

作者： Wenqi Gao Fangyuan Xiong Ying lu Wei Xin Haihua Wang Gangpeng Feng Chiping kong Lei Fang Xiaoping Gao Yushun Chen State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences University of Chinese Academy of Sciences Jiangxi Institute for Fisheries Sciences Poyang Lake Fisheries Research Centre of Jiangxi Province East China Sea Fisheries Research Institute Chinese Academy of Fishery Sciences Jiujiang Institute of Agricultural Sciences

Background Although phytoplankton are important primary producers in food webs, they are relatively less studied in large rivers compared to other types of systems. To fill this research gap, we studied phytoplankton taxonomic and functional composition and their relationships with water quality, habitat, climate, and land use across 30 river sections in the middle and lower reaches of the Yangtze River during 2017–*** Major observed phytoplankton groups were cyanobacteria, bacillariophyta, and chlorophyta. Phytoplankton total abundance, total biomass, and species richness significantly decreased in the dry season compared to the wet season, with the species and functional composition differing significantly between seasons. Phytoplankton species differences between seasons were mainly contributed by Oscillatoria sp., Pseudanabaena sp., and Melosira granulata. The dfferences in phytoplankton functional groups between seasons were mainly contributed by P（including Closterium sp., Melosira sp.）, Lo（including Merismopedia sp., Peridinium sp., Ceratium sp., and Gymnodinium sp.）, and J（including Pediastrum sp., Tetraedron sp., Crucigenia sp., Scenedesmus sp., and Coelastrum sp.）. The variance partitioning showed that water quality（NO3-N, total suspended solids, turbidity） and habitat（water flow, river bank and river channel conditions） were critical factors in shaping phytoplankton patterns, followed by climate and land *** Results indicated that there was significant seasonal variation of phytoplankton in the Yangtze River, with water quality and habitat primarily driving phytoplankton patterns. Our study contributes to the understanding of natural and anthropogenic factors that drive seasonal successional processes of phytoplankton in the Yangtze River. These findings have important implications for environmental management as well as towards the ecological restoration of large rivers.

关键词： Yangtze River Phytoplankton Functional group Water quality Physical habitat

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

Human bone marrow mesenchymal stem cell-derived exosomes loaded with gemcitabine inhibit pancreatic cancer cell proliferation by enhancing apoptosis

引用

World Journal of Gastrointestinal Oncology 2024年第9期16卷 4006-4013页

作者： Zu-Gui Tang Tie-Mei Chen Yi lu Zhe Wang Xi-Cheng Wang Yi kong Department of Oncology The First Affiliated Hospital of Guangdong Pharmaceutical UniversityGuangzhou 510080Guangdong ProvinceChina Faculty of Pharmaceutical Sciences Shenzhen University of Advanced TechnologyShenzhen 518000Guangdong ProvinceChina Guangdong Pharmaceutical University Guangzhou 510006Guangdong ProvinceChina

BACKGROUND Pancreatic cancer remains one of the most lethal malignancies,and has limited effective ***(GEM),a chemotherapeutic agent,is commonly used for clinical treatment of pancreatic cancer,but it has characteristics of low drug delivery efficiency and significant side *** study tested the hypothesis that human bone marrow mesenchymal stem cell(MSC)-derived exosomes loaded with GEM(Exo-GEM)would have a higher cytotoxicity against human pancreatic cancer cells by enhancing their *** To investigate the cytotoxicity of MSC-derived Exo-GEM against pancreatic cancer cells in *** Exosomes were isolated from MSCs and characterized by transmission electron microscopy and nanoparticle tracking ***-GEM through electroporation,sonication,or incubation,and the loading efficiency was *** cytotoxicity of Exo-GEM or GEM alone against human pancreatic cancer Panc-1 and MiaPaca-2 cells was assessed by MTT and flow cytometry *** The isolated exosomes had an average size of 76.7 *** encapsulation efficacy and loading efficiency of GEM by electroporation and sonication were similar and significantly better than *** cytotoxicity of Exo-GEM against pancreatic cancer cells was stronger than free GEM and treatment with 0.02μM Exo-GEM significantly reduced the viability of both Panc-1 and MiaPaca-2 ***,Exo-GEM enhanced the frequency of GEMinduced apoptosis in both cell *** Human bone marrow MSC-derived Exo-GEM have a potent cytotoxicity against human pancreatic cancer cells by enhancing their apoptosis,offering a promising drug delivery system for improving therapeutic outcomes.

关键词： Mesenchymal stem cells Exosomes Extracellular vesicles Gemcitabine Pancreatic cancer Drug delivery

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

Epigenetic regulation of SARS-Cov-2 spike protein modulates cellular viability and nascent RNA transcription in neuronal cells

引用

Genes & Diseases 2024年第2期11卷 535-538页

作者： Xi kong Peng lu Jinyue Zhang Zheng Bao Chenghao Kuang Bingqing Xie Jianhua Peng Ning Ma Yong Jiang Shigang Yin Laboratory of Neurological Diseases and Brain Function The Affiliated Hospital of Southwest Medical UniversityLuzhouSichuan 646000China Institute of Epigenetics and Brain Science Southwest Medical UniversityLuzhouSichuan 646000China Department of Neurosurgery The Affiliated Hospital of Southwest Medical UniversityLuzhouSichuan 646000China Inflammation and Allergic Diseases Research Unit The Affiliated Hospital of Southwest Medical UniversityLuzhouSichuan 646000China

SARS-CoV-2 has been demonstrated to be highly susceptible to neuron-and glial-like cells,1 but there is no consensus regarding how the virus affects neurons following *** is therefore unknown if and how SARS-CoV-2 maintains the homeostasis of neuronal ***,we revealed that the receptor-binding domain(RBD)of the SARS-CoV-2 spike protein acted as an extracellular remodeling component to undermine epigenetic regulation,perturbnascentRNA(nsRNA)transcription,promote mitochondrial biogenesis,and increase cellular viability in SH-SY5Y cells.

关键词： invasion homeostasis maintain

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

Feedback enhanced tumor targeting delivery of albumin-based nanomedicine to amplify photodynamic therapy by regulating AMPK signaling and inhibiting GSTs

引用

Chinese Chemical Letters 2024年第8期35卷 481-485页

作者： Jiaqi Huang Renjiang kong Yanmei Li Ni Yan Yeyang Wu Ziwen Qiu Zhenming lu Xiaona Rao Shiying Li Hong Cheng School of Biomedical Engineering&Guangdong Provincial Key Laboratory of Construction and Detection in Tissue Engineering Southern Medical UniversityGuangzhou 510515China School of Pharmaceutical Sciences Guangzhou Medical UniversityGuangzhou 511436China

Oxidative therapies receive a limited antitumor efficiency due to the insufficient reactive oxygen species(ROS)levels at focal sites and the evolvement of antioxidant defense ***,we develop an albumin-based nanomedicine to co-deliver chlorin e6(Ce6)and COH-SR4(CS),which can simultaneously enhance the yield and lethality of intracellular ROS for amplified photodynamic therapy(PDT).In which,CS acts as both an activator of AMP-activated protein kinase(AMPK)and an inhibitor of glutathione S-transferases(GSTs).Benefiting from it,the prepared HSA-Ce6@COH-SR4(HCCS)enables positive feed-back uptake by promoting AMPK phosphorylation,leading to rapid and extensive tumor accumulation of *** a result,HCCS obviously increases the ROS production to elevate intracellular oxidative ***,HCCS can inhibit GSTs to disturb the antioxidant defense system of tumor cells,intensifying the oxidative damage of ***,the PDT of HCCS is significantly strengthened by improving the ROS yield and lethality,which greatly declines the proliferation of breast cancer in *** study may open a window in the development of drug co-delivery system for enhanced oxidative therapy of tumors.

关键词： Human serum albumin Drug delivery Reactive oxygen species Positive feedback uptake Oxidative damage

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

Ionic liquid-based in situ dynamically self-assembled cationic lipid nanocomplexes(CLNs)for enhanced intranasal siRNA delivery

引用

Chinese Chemical Letters 2024年第7期35卷 367-371页

作者： luyu Zhang Zirong Dong Shuai Yu Guangyue Li Weiwen kong Wenjuan Liu Haisheng He Yi lu Wei Wu Jianping Qi Key Laboratory of Smart Drug Delivery of MOE School of PharmacyFudan UniversityShanghai 201203China School of Pharmacy Shandong Academy of SciencesQilu University of TechnologyJi'nan 250353China College of Chemical Engineering North China University of Science and TechnologyTangshan 063210China

This research aims to develop a non-invasive strategy for small interfering RNA(siRNA)nasal delivery based on ionic liquids(ILs)and cationic lipid(2,3-dioleoyloxy-propyl)-trimethylammonium-chloride(DOTAP).Other than the classical role of penetration enhancer,ILs also acted as superior solvents to simultaneously load siRNA and DOTAP,forming siRNA-DOTAP-ILs(siRNA-DILs)*** nasal mucosa penetration,DOTAP and ILs components self-assembled into cationic lipid nanocomplexes to load siRNA for enhanced in situ *** siRNA-DILs demonstrated resistance against RNase,significant mucosa penetration,prolonged nasal retention,and satisfying gene-silencing efficacy at lower ***,DILs were also able to deliver KCa3.1-targeted siRNA effectively for the treatment of allergic rhinitis in rat model by nasal ***,DILs have great potentials to deliver biological macromolecules across nasal mucosa by in situ dynamic self-assembly.

关键词： Ionic liquids Cationic lipids Lipid nanoparticles siRNA Allergic rhinitis

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：