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Vascular endothelial growth factor protein and gene delivery by novel nanomaterials for promoting liver regeneration after partial hepatectomy
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作者 Yun Jin Ying-Hao Guo +4 位作者 Jia-Cheng Li Qi Li Dan Ye Xiao-Xiao Zhang Jiang-Tao Li 《World Journal of Gastroenterology》 SCIE CAS 2023年第24期3748-3757,共10页
Partial hepatectomy(PH)can lead to severe complications,including liver failure,due to the low regenerative capacity of the remaining liver,especially after extensive hepatectomy.Liver sinusoidal endothelial cells(LSE... Partial hepatectomy(PH)can lead to severe complications,including liver failure,due to the low regenerative capacity of the remaining liver,especially after extensive hepatectomy.Liver sinusoidal endothelial cells(LSECs),whose proliferation occurs more slowly and later than hepatocytes after PH,compose the lining of the hepatic sinusoids,which are the smallest blood vessels in the liver.Vascular endothelial growth factor(VEGF),secreted by hepatocytes,promotes LSEC proliferation.Supplementation of exogenous VEGF after hepatectomy also increases the number of LSECs in the remaining liver,thus promoting the reestablishment of the hepatic sinusoids and accelerating liver regeneration.At present,some shortcomings exist in the methods of supplementing exogenous VEGF,such as a low drug concentration in the liver and the reaching of other organs.Moreover,VEGF should be administered multiple times and in large doses because of its short half-life.This review summarized the most recent findings on liver regeneration and new strategies for the localized delivery VEGF in the liver. 展开更多
关键词 Liver regeneration Vascular endothelial growth factor nano materials Liver resection
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The Microparticles SiOx Loaded on PAN-C Nanofiber as Three-Dimensional Anode Material for High-Performance Lithium-Ion Batteries
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作者 Jiahao Wang Jie Zhou +2 位作者 Zhengping Zhao Feng Chen Mingqiang Zhong 《Journal of Renewable Materials》 EI 2023年第8期3309-3332,共24页
Three-dimensional C/SiOx nanofiber anode was prepared by polydimethylsiloxane(PDMS)and polyacrylonitrile(PAN)as precursors via electrospinning and freeze-drying successfully.In contrast to conventional carbon cover-ing... Three-dimensional C/SiOx nanofiber anode was prepared by polydimethylsiloxane(PDMS)and polyacrylonitrile(PAN)as precursors via electrospinning and freeze-drying successfully.In contrast to conventional carbon cover-ing Si-based anode materials,the C/SiOx structure is made up of PAN-C,a 3D carbon substance,and SiOx load-ing steadily on PAN-C.The PAN carbon nanofibers and loaded SiOx from pyrolyzed PDMS give increased conductivity and a stable complex structure.When employed as lithium-ion batteries(LIBs)anode materials,C/SiOx-1%composites were discovered to have an extremely high lithium storage capacity and good cycle per-formance.At a current density of 100 mA/g,its reversible capacity remained at 761 mA/h after 50 charge-dis-charge cycles and at 670 mA/h after 200 cycles.The C/SiOx-1%composite aerogel is a particularly intriguing anode candidate for high-performance LIBs due to these appealing qualities. 展开更多
关键词 Batteries anode materials carbon nanofibers composites aerogel
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New Nano Polymer Materials for Composite Exterior-Wall Coatings
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作者 Yue Yu 《Fluid Dynamics & Materials Processing》 EI 2023年第10期2681-2694,共14页
A triethylenetetramine epoxy mixture was synthesized through the reaction of a low-molecular-weight liquid epoxy resin with triethylenetetramine(TETA).Then triethyltetramine(TETA)was injected dropwise into a pro-pylen... A triethylenetetramine epoxy mixture was synthesized through the reaction of a low-molecular-weight liquid epoxy resin with triethylenetetramine(TETA).Then triethyltetramine(TETA)was injected dropwise into a pro-pylene glycol methyl ether(PM)solution for chain extension reaction.A hydrophilic andflexible polyether seg-ment was introduced into the hardener molecule.The effects of TETA/DGEPG,reaction temperature and reaction time on the epoxy conversion of polyethylene glycol diglycidyl ether(DGEPG)were studied.In addition,several alternate strategies to add epoxy resin to the high-speed dispersion machine and synthesize MEA DGEBA adduct(without catalyst and with bisphenol A diglycidyl ether epoxy resin)were compared.It was found that the higher the molecular weight of triethylenetetramine,the longer the chain segment of the surface active molecule.When the equivalence ratio of amine hydrogen and epoxy group is low,the stability of lotion is good.When the ratio of amine hydrogen to epoxy group is large,the content of triethylenetetramine is small.The main objective of this study is the provision of new data and knowledge for the development of new materials in the coating and electronic industry. 展开更多
关键词 Water-based coating triethylenetetramine(TETA) surface active agent nano polymer materials TRIETHYLENETETRAMINE
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Tuning the particle size and morphology of high energetic material nanocrystals 被引量:7
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作者 Raj KUMAR Prem Felix SIRIL Pramod SONI 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2015年第4期382-389,共8页
Morphology controlled synthesis of nanoparticles of powerful high energetic compounds(HECs) such as l,3,5-trinitro-l,3,5-triazinane(RDX) and 1,3,5,7-tetranitro-l,3,5,7-tetrazocane(HMX) were achieved by a simple solven... Morphology controlled synthesis of nanoparticles of powerful high energetic compounds(HECs) such as l,3,5-trinitro-l,3,5-triazinane(RDX) and 1,3,5,7-tetranitro-l,3,5,7-tetrazocane(HMX) were achieved by a simple solvent—antisolvent interaction(SAI) method at 70 ℃.The effects of different solvents on particle size and morphology of the prepared nano-HECs were studied systematically.Particle size and morphology of the nano-HECs was characterized using field emission scanning electron microscopy(FE-SEM) imaging.X-ray diffraction(XRD) and Fourier transform infrared(FTIR) spectroscopy studies revealed that RDX and HMX were precipitated in their most stable polymorphic forms,i.e.a and P,respectively.Thermogravimetric analysis coupled with differential scanning calorimetry(TGA-DSC) studies showed that the thermal response of the nanoparticles was similar to the respective raw-HECs.HEC nanoparticles with spherical and rod shaped morphology were observed under different solvent conditions.The mean particle size also varied considerably with the use of different solvents. 展开更多
关键词 平均粒径 高含能材料 形貌 纳米晶体 场发射扫描电子显微镜 差示扫描量热法 纳米颗粒 纳米粒子
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Construction and Properties of Structure-and Size-controlled Micro/Nano-energetic Materials 被引量:20
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作者 HUANG Bing CAO Minhua +2 位作者 NIE Fude HUANG Hui HU Changwen 《Defence Technology(防务技术)》 SCIE EI CAS 2013年第2期75-103,共29页
The recent research progress of structure- and size-controlled micro/nano-energetic materials is reviewed, which properties are fundamentally different from those of their corresponding bulk materials. The development... The recent research progress of structure- and size-controlled micro/nano-energetic materials is reviewed, which properties are fundamentally different from those of their corresponding bulk materials. The development of the construction strategies for achieving zero-dimensional (0D), one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D) micro/nanostructures from energetic molecules is introduced. Also, an overview of the unique properties induced by micro/nanostructures and size effects is provided. Special emphasis is focused on the size-dependent properties that are different from those of the conventional micro-sized energetic materials, such as thermal decomposition, sensitivity, combustion and detonation, and compaction behaviors. A conclusion and our view of the future development of micro/nano-energetic materials and devices are given. 展开更多
关键词 applied chemistry STRUCTURE SIZE micro/nano-energetic materials construction technology PROPERTY
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Graphene oxide assisted facile hydrothermal synthesis of LiMn_(0.6)Fe_(0.4)PO_4 nanoparticles as cathode material for lithium ion battery 被引量:3
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作者 Changchang Xu Li Li +6 位作者 Fangyuan Qiu Cuihua An Yanan Xu Ying Wang Yijing Wang Lifang Jiao Huatang Yuan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2014年第3期397-402,共6页
Assisted by graphene oxide(GO),nano-sized LiMn_(0.6)Fe_(0.4)PO_4 with excellent electrochemical performance was prepared by a facile hydrothermal method as cathode material for lithium ion battery.SEM and TEM images i... Assisted by graphene oxide(GO),nano-sized LiMn_(0.6)Fe_(0.4)PO_4 with excellent electrochemical performance was prepared by a facile hydrothermal method as cathode material for lithium ion battery.SEM and TEM images indicate that the particle size of LiMn_(0.6)Fe_(0.4)PO_4(S2)was about 80 nm in diameter.The discharge capacity of LiMn_(0.6)Fe_(0.4)PO_4 nanoparticles was 140.3 mAh-g^1 in the first cycle.It showed that graphene oxide was able to restrict the growth of LiMn_(0.6)Fe_(0.4)PO_4 and it in situ reduction of GO could improve the electrical conductivity of LiMn_(0.6)Fe_(0.4)PO_4 material. 展开更多
关键词 锂离子电池 正极材料 氧化石墨 纳米粒子 氧化物 水热合成 电化学性能 纳米尺寸
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Adsorption of phenol from aqueous solution by a hierarchical micro-nano porous carbon material 被引量:4
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作者 Liu Chengbao Chen Zhigang +5 位作者 Ni Chaoying Chen Feng Gu Cheng Cao Yu Wu Zhengying Li Ping 《Rare Metals》 SCIE EI CAS CSCD 2012年第6期582-589,共8页
A hierarchical micro-nano porous carbon material (MNC) was prepared using expanded graphite (EG), sucrose, and phosphoric acid as raw materials, followed by sucrose-phosphoric acid solution impregnation, solidificatio... A hierarchical micro-nano porous carbon material (MNC) was prepared using expanded graphite (EG), sucrose, and phosphoric acid as raw materials, followed by sucrose-phosphoric acid solution impregnation, solidification, carbonization and activation. Nitrogen adsorption and mercury porosimetry show that mixed nanopores and micropores coexist in MNC with a high specific surface area of 1978 m2·g-1 and a total pore volume of 0.99 cm3·g-1. In addition, the MNC is found to consist of EG and activated carbon with the latter deposited on the interior and the exterior surfaces of the EG pores. The thickness of the activated carbon layer is calculated to be about one hundred nanometers and is further confirmed by scanning electron microscope (SEM) and transmission election microscope (TEM). A maximum static phenol adsorption of 241.2 mg·g-1 was obtained by using MNC, slightly higher than that of 220.4 mg·g-1 by using commercial activated carbon (CAC). The phenol adsorption kinetics were investigated and the data fitted well to a pseudo-second-order model. Also, an intra-particle diffusion mechanism was proposed. Furthermore, it is found that the dynamic adsorption capacity of MNC is nearly three times that of CAC. The results suggest that the MNC is a more efficient adsorbent than CAC for the removal of phenol from aqueous solution. 展开更多
关键词 micro-nano porous carbon materials expanded graphite activated carbon phenol adsorption KINETICS
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Preparation of Nano-porous Materials(Ⅰ) by Polymerization of Amphiphile Self-assemblies 被引量:2
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作者 YUE Dong-mei +2 位作者 YU Jiong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第1期112-119,共8页
The polymerization of amphiphilic self assemblies is a promising method to synthesize nano structured materials with novel properties. These materials have many attractive features for their application in biomedical ... The polymerization of amphiphilic self assemblies is a promising method to synthesize nano structured materials with novel properties. These materials have many attractive features for their application in biomedical area and materials science, such as catalysis, separation, surface modification, and therapeutics areas. A general review on the polymerization of lipids and surfactant self assemblies to amphiphilic self assemblies is given in this paper with 49 references. The polymerization and the subsequently resulted structure of lipids in different morphologies are summarized. The polymerization of polymerizable surfactants(surfmers) in emulsion and liquid crystalline phases are also discussed. The potential application of new nano porous materials is briefly described. 展开更多
关键词 纳米多孔材料 制备 聚合反应 自组装 两亲物 液晶 类脂 表面活性剂
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Preparation of nano-PANI@MnO_2 by surface initiated polymerization method using as a nano-tubular electrode material:The amount effect of aniline on the microstructure and electrochemical performance 被引量:1
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作者 Fen Ran Yunlong Yang +5 位作者 Lei Zhao Xiaoqin Niu Dingjun Zhang Lingbin Kong Yongchun Luo Long Kang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第4期388-393,共6页
In this study,nano-polyanline and manganese oxide nanometer tubular composites(nano-PANI@MnO2)were prepared by a surface initiated polymerization method and used as electrochemical capacitor electrode materials; and t... In this study,nano-polyanline and manganese oxide nanometer tubular composites(nano-PANI@MnO2)were prepared by a surface initiated polymerization method and used as electrochemical capacitor electrode materials; and the effect of aniline amount on the microstructure and electrochemical performance was investigated. The microstructures and surface morphologies of nano-PANI@MnO2 were characterized by X-ray diffraction,scanning electron microscopy and fourier transformation infrared spectroscope. The electrochemical performance of these composite materials was performed with cyclic voltammetry,charge–discharge test and electrochemical impedance spectroscopy,respectively. The results demonstrate that the feed ratio of aniline to MnO2 played a very important role in constructing the hierarchically nano-structure,which would,hence,determine the electrochemical performance of the materials. Using the templateassisted strategy and controlling the feed ratio of aniline to MnO2,the nanometer tubular structure of nanoPANI@MnO2 was obtained. A maximum specific capacitance of 386 F/g was achieved in aqueous 1 mol/L Na NO3 electrolyte with the potential range from 0 to 0.6 V(vs. SCE). 展开更多
关键词 电化学性能 纳米结构 电极材料 表面形貌 管状结构 聚苯胺 聚合方法 引发
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Synthesis and Characterization of Storage Energy Materials Prepared from Nano-crystalline Cellulose/Polyethylene Glycol 被引量:5
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作者 Xiao Ping YUAN En Yong DING 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第8期1129-1132,共4页
This paper gives a brief report of the synthesis of a new kind of solid-solid phase change materials (SSPCMs), nano-crystalline cellulose/polyethylene glycol (NCC/PEG). These PCMs have very high ability for energy sto... This paper gives a brief report of the synthesis of a new kind of solid-solid phase change materials (SSPCMs), nano-crystalline cellulose/polyethylene glycol (NCC/PEG). These PCMs have very high ability for energy storage, and their enthalpies reach 103.8 J/g. They are composed of two parts, PEG as functional branches for energy storage, and NCC as skeleton. The flexible polymer PEG was grafted onto the surface of rigid powder of NCC by covalent bonds. The results of DSC, FT-IR were briefly introduced, and some comments were also given. 展开更多
关键词 纳米水晶纤维素 聚乙二醇 相变材料 储能材料 DSC
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Investigation of nano-talc as a filling material and a reinforcing agent in high density polyethylene (HDPE) 被引量:1
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作者 CHEN Nanchun MA Lei ZHANG Tao 《Rare Metals》 SCIE EI CAS CSCD 2006年第z1期422-425,共4页
An experiment of producing high density polyethylene (HDPE) nano-composite filled with 4wt.% talc was presented. Acting as filler and a reinforcing agent in the HDPE, talc powder, sized at around 5 μm, was surface-tr... An experiment of producing high density polyethylene (HDPE) nano-composite filled with 4wt.% talc was presented. Acting as filler and a reinforcing agent in the HDPE, talc powder, sized at around 5 μm, was surface-treated with aluminum diethylene glycol dinitrate coupling agent before adding to the HDPE. Analyses of the reinforced HDPE nano-composite show significant improvement in its mechanical properties including, tensile strength (>26 MPa), break elongation (<1.1%), flexural strength (>22 MPa), and friction coefficients<0.11. The results demonstrate that, after surface-treated, talc can be used as a promising filling material and a reinforcing agent in making HDPE nano-composite. 展开更多
关键词 HDPE TALC FILLING material reinforcing AGENT nano-COMPOSITE mechanical properties
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Carbon dioxide catalytic conversion to nano carbon material on the iron–nickel catalysts using CVD-IP method 被引量:4
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作者 Jiaquan Hu Zhanglong Guo +2 位作者 Wei Chu Le Li Tao Lin 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第5期620-625,共6页
The over-consumption of fossil fuels resulted in the large quantity emission of carbon dioxide(CO2), which was the main reason for the climate change and more extreme weathers. Hence, it is extremely pressing to explo... The over-consumption of fossil fuels resulted in the large quantity emission of carbon dioxide(CO2), which was the main reason for the climate change and more extreme weathers. Hence, it is extremely pressing to explore efficient and sustainable approaches for the carbon-neutral pathway of CO2 utilization and recycling. In our recent works with this context, we developed successfully a novel "chemical vapor deposition integrated process(CVD-IP)" technology to converting robustly CO2 into the value-added solid-form carbon materials.The monometallic Fe Ni0–Al2O3(FNi0) and bimetallic Fe Nix–Al2O3(FNi2, FNi4, FNi8 and FNi20) samples were synthesized and effective for this new approach. The catalyst labeled FNi8 gave the better performance, exhibited the single pass solid carbon yield of 30%. These results illustrated alternative promising cases for the CO2 capture utilization storage(CCUS), by means of the CO2 catalytic conversion into the solid-form nano carbon materials. 展开更多
关键词 纳米碳材料 镍催化剂 催化转化 二氧化碳 化学气相沉积 CO2 碳纳米材料 化石燃料
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Experimental Research on Toluene Degradation in Plasma as the Driving Force of Nanomaterials 被引量:2
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作者 Tao Zhu Xiaoyang Li +2 位作者 Wenjuan Zhao Ni Xia Xiaojia Wang 《Open Journal of Applied Sciences》 2015年第10期586-594,共9页
Plasma technology has some shortcomings, such as higher energy consumption and byproducts produced in the reaction process. However non-thermal plasma associated with catalyst can resolve these problems. So this kind ... Plasma technology has some shortcomings, such as higher energy consumption and byproducts produced in the reaction process. However non-thermal plasma associated with catalyst can resolve these problems. So this kind of technology was paid more and more attention to treat waste gas. In this paper, we make use of this technology to decompose toluene under different electric field and packed materials. At the same time, the mechanism of toluene decomposition using plasma and catalyst is discussed. The experimental results show toluene decomposition increases with electric field strength increasing and flow velocity and initial concentration decreasing. There are four conditions in plasma: without packed materials (1);with packed materials (2);with BaTiO3 in the surfaces of packed materials (3);and with nanometer Ba0.8Sr0.2Zr0.1Ti0.9O3 (4). Toluene decomposition represents a obvious trend, that is, η(4) > η(3) > η(2) > η(1). The best decomposition efficiency of toluene arrives at 95%. 展开更多
关键词 NON-THERMAL PLASMA TOLUENE DECOMPOSITION Efficiency nano-materialS
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Computational Analysis of the Effect of Nano Particle Material Motion on Mixed Convection Flow in the Presence of Heat Generation and Absorption
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作者 Muhammad Ashraf Amir Abbas +3 位作者 Saqib Zia Yu-Ming Chu Ilyas Khan Kottakkaran Sooppy Nisar 《Computers, Materials & Continua》 SCIE EI 2020年第11期1809-1823,共15页
The present study is concerned with the physical behavior of the combined effect of nano particle material motion and heat generation/absorption due to the effect of different parameters involved in prescribed flow mo... The present study is concerned with the physical behavior of the combined effect of nano particle material motion and heat generation/absorption due to the effect of different parameters involved in prescribed flow model.The formulation of the flow model is based on basic universal equations of conservation of momentum,energy and mass.The prescribed flow model is converted to non-dimensional form by using suitable scaling.The obtained transformed equations are solved numerically by using finite difference scheme.For the analysis of above said behavior the computed numerical data for fluid velocity,temperature profile,and mass concentration for several constraints that is mixed convection parameterλt,modified mixed convection parameterλc,Prandtl number Pr,heat generation/absorption parameterδ,Schmidt number Sc,thermophoresis parameter Nt,and thermophoretic coefficient k are sketched in graphical form.Numerical results for skin friction,heat transfer rate and the mass transfer rate are tabulated for various emerging physical parameters.It is reported that in enhancement in heat,generation boosts up the fluid temperature at some positions of the surface of the sphere.As heat absorption parameter is decreased temperature field increases at position X=π/4 on the other hand,no alteration at other considered circumferential positions is noticed. 展开更多
关键词 nano material mixed convection finite difference method heat generation/absorption SPHERES
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Melting Characteristics of a Phase Change Material Mixed with Nano Particles of Cobalt Oxide Bounded in a Trapezoidal Structure
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作者 Waris Ali Asif Ali Shaikh +1 位作者 Feroz Shah Sajjad Hussain 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第1期255-268,共14页
A novel trapezoidal design for storage of heat energy through melting of phase-change material(PCM)is investigated.Latent heat thermal energy storage system(LHTES)is a promising option to diminish mis-match between en... A novel trapezoidal design for storage of heat energy through melting of phase-change material(PCM)is investigated.Latent heat thermal energy storage system(LHTES)is a promising option to diminish mis-match between energy consumption and supply.For this purpose,Paraffin:Rubitherm-35(RT35)material is successively melted in aluminum structure which is heated from one side and the other sides are kept adiabatic.Melting of PCM is observed experimentally and melt fronts are photographed for various time lengths.The fluid-solid module in COMSOL Multiphysics 5.4 has been utilized.The transient heat conduction with enthalpy function is hired.Simulations are carried out for enhancement of thermal conductivity through addition of nano-entities of cobalt oxide Co3O4.Themelting time is notably reduced with inclusion of nano-entities to enhance thermal conductivity.The time spans for melt start and total melt in case of pure PCM are 375 and 4500(s)respectively whereas for the nano mix case,these are 150 and 3000 s.Thus 33%shorter time length is noticed for charging of the PCM trapezoidal matrix with nano entities of Co3O4 aremixed.The results fromsimulation and lab observations depict similar patterns and are in quite close comparison. 展开更多
关键词 Trapezoidal enclosure nano entities heat transfer phase change material COMSOL multiphysics 5.4 numerical simulation
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Preparation of nano-structured Ag solid materials and application to surface-enhanced Raman scattering 被引量:1
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作者 易早 陈艳 +5 位作者 陈善俊 谭秀兰 牛高 罗江山 唐永建 易有根 《Journal of Central South University》 SCIE EI CAS 2011年第6期1877-1882,共6页
Silver nano-particles with average diameter of about 60 nm were compacted in a high-strength mold under different pressures at 523 K to produce nano-structured Ag solid materials. The structure and characteristic of t... Silver nano-particles with average diameter of about 60 nm were compacted in a high-strength mold under different pressures at 523 K to produce nano-structured Ag solid materials. The structure and characteristic of the nano-structured Ag solid materials (NSS-Ag) were studied using X-ray diffraction (XRD), scanning electron microscope (SEM) and Raman spectrometer. The NSS-Ag could be used as highly efficient surface-enhanced Raman scattering (SERS) active substrates. The common probe molecules Rhodamine 6G (R6G, 1×10-10 mol/L) were used to test the SERS activity on these substrates at very low concentrations. It is found that the SERS enhancement ability is dependent on the density of NSS-Ag. When the relative density of NSS-Ag is 83.87%, the materials reveal great SERS signal. 展开更多
关键词 表面增强拉曼散射 银纳米粒子 固体材料 纳米结构 SERS活性 扫描电子显微镜 应用 制备
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Carbon Nano Material Synthesis from Polyethylene by Chemical Vapour Deposition
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作者 Pravin Jagdale Madhuri Sharon +2 位作者 Golap Kalita Noor Mahmad Nabi Maldar Maheshwar Sharon 《Advances in Materials Physics and Chemistry》 2012年第1期1-10,共10页
Three different types of Polyethylene family, High Density Polyethylene, (HDPE), Low Density polyethylene (LDPE) and Linear Low Density polyethylene (LLDPE) polymers having different molecular weight and density;were ... Three different types of Polyethylene family, High Density Polyethylene, (HDPE), Low Density polyethylene (LDPE) and Linear Low Density polyethylene (LLDPE) polymers having different molecular weight and density;were pyrolyzed in the temperature range of 550°C - 1050°C under H2, N2 and Ar gases. Taguchi Optimization technique was applied to find out the best operating conditions to get maximum yield of carbon nano material (CNM). For Taguchi op- timization, experimental set up was done in two different temperature ranges i.e. 550°C - 750°C and 850°C - 1050°C. CNMs synthesized were characterized by SEM, TEM, Micro Raman and XRD analysis. HDPE was found to yield maximum CNM. Its pyrolysis at 750°C under hydrogen atmosphere for 2h gave carbon nano beads and some carbon nano tubes. Whereas under same conditions at 1050°C more multi wall carbon nano tubes (MWCNT) were produced, with some carbon nano beads. XRD data confirmed the graphitic nature of carbon-nanotube. The intensities of G-band and D-band of Raman spectra suggested that CNM has more defect sites and spectra were similar for CNM obtained in both the temperature ranges. The TGA analysis of CNM obtained at 550°C - 750°C, indicated that they are not amor- phous carbon and CNM obtained at 850°C - 1050°C decomposed at 624°C - 668°C;suggesting that CNT synthesized at this temperature range were more crystalline than what was obtained at the 550°C - 750°C. 展开更多
关键词 POLYETHYLENE Pyrolysis LDPE HDPE LLDPE CARBON nano material (CNM) CARBON nano BEADS (CNB) CARBON nano Tubes (CNT)
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Performance analysis of thermal storage unit with possible nano enhanced phase change material in building cooling applications
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作者 Solomon G Ravikumar Ravikumar T S +1 位作者 Raj V Antony Aroul Velraj R 《储能科学与技术》 CAS 2013年第2期91-102,共12页
The heat transfer performance of the phase change materials used in free cooling and air conditioning applications is low,due to the poor thermal conductivity of the materials.The recent phenomenal advancement in nano... The heat transfer performance of the phase change materials used in free cooling and air conditioning applications is low,due to the poor thermal conductivity of the materials.The recent phenomenal advancement in nano technology provides an opportunity for an appreciable enhancement in the thermal conductivity of the phase change materials.In order to explore the possibilities of using nano technology for various applications,a detailed parametric study is carried out,to analyse the heat transfer enhancement potential with the thermal conductivity of the conventional phase change materials and nano enhanced phase change materials under various flow conditions of the heat transfer fluid.Initially,the theoretical equation,used to determine the time for outward cylindrical solidification of the phase change material,is validated with the experimental results.It is inferred from the parametric studies,that for paraffinic phase change materials with air as the heat transfer fluid,the first step should be to increase the heat transfer coefficient to the maximum extent,before making any attempt to increase the thermal conductivity of the phase change materials,with the addition of nano particles.When water is used as the phase change material,the addition of nano particles is recommended to achieve better heat transfer,when a liquid is used as the heat transfer fluid. 展开更多
关键词 thermal storage phase change material nano particle solidification time building cooling doi.3969/j.issn.2095-4239.2013.02.002 CLC number:TK 51 Document code:A Article ID-4239(2013)02-091-12
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Synthesis and room temperature ionic conductivity of nano-LaF_3 bulk material
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作者 吴大雄 吴希俊 +1 位作者 吕燕飞 王晖 《中国有色金属学会会刊:英文版》 EI CSCD 2006年第4期828-832,共5页
The ionic conductivity (at room temperature) of nano-LaF3 bulk material and a new discovered phenomenon of increasing ionic conductivity caused by grain boundary relaxation activated by AC (alternating current) shocki... The ionic conductivity (at room temperature) of nano-LaF3 bulk material and a new discovered phenomenon of increasing ionic conductivity caused by grain boundary relaxation activated by AC (alternating current) shocking were reported. Nano-crystalline powder of LaF3 with average grain size of 16.7 nm was synthesized with a method of direct precipitation from aqueous solution. Particle size and shape of LaF3 nano-crystalline powder were analyzed by XRD and TEM. Nano-LaF3 bulk material was prepared by compacting the powder to 1 GPa at room temperature and vacuum of 10?4 Pa. The ionic conductivity of nano-LaF3 bulk material was studied with complex impedance spectra at room temperature. The ionic conductivity of nano-LaF3 bulk material (10?5 S/cm) at room temperature is significantly increased compared with that of single crystal LaF3 (10?6 S/cm). A special phenomenon is observed for the first time that the ionic conductivity increases gradually with AC scanning times. 展开更多
关键词 LAF3 纳米材料 纳米晶 离子电导性 阻抗谱 稀土
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FORMING AND PRECISION MACHINING TO NANOMATERIALS LUMP
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作者 ZhanJie ZhangJin ChenBingkui ChenXiaoan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第4期534-536,共3页
The technology of forming and machining lump nano-materials has been investigated.Grinding, abrasive machining test has been conducted to Fe, Co, Ni and A1 lump nano-materials.Experiments have been done to measure gri... The technology of forming and machining lump nano-materials has been investigated.Grinding, abrasive machining test has been conducted to Fe, Co, Ni and A1 lump nano-materials.Experiments have been done to measure grinding force, grinding thermal, machining roughness and micro-hardness. Image analysis is carried out by metallographic and scanning tunnel microscopic microscope. Researches provide the basis data for forming and machining lump nano-materials. 展开更多
关键词 纳米材料 磨床 耐磨测试 测量方法
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