检索结果-南通市图书馆

Effect of electrolytes on electrochemical properties of graphene sheet covered with polypyrrole thin layer

Progress in Natural science:materials International 2011年第6期21卷 460-466页

作者： Ya-meng CAI~(1,2),Zong-yi QIN~1,Long CHEN~2 1.State Key Laboratory for Modification of Chemical Fibers and Polymer materials, donghua university,shanghai 201620,china 2.college of material science and engineering,donghua university,shanghai 201620,china [a] State Key Laboratory for Modification of Chemical Fibers and Polymer materials Donghua University Shanghai 201620 China [b] college of material science and engineering Donghua University Shanghai 201620 China

Graphene sheet(GS) was successfully covered with a polypyrrole(PPy) thin layer through in situ chemical oxidative polymerization of pyrrole monomers in aqueous solution by using GS as a support material and ferric trichloride as an *** resulting nanocomposite was studied by field emission scanning electron microscopy(FE-SEM),Fourier transform infrared spectroscopy(FT-IR) and electrical measurements,including cyclic voltammetry(CV),galvanostatic charge/discharge experiment (GCD),and impedance spectroscopy(EIS).It has been found that the nanocomposite exhibited a typically curved and layer-like structure,and conformational change of PPy chains occurred due to the n-n stacking interaction between the graphitic structures in GS and aromatic rings of the PPy *** attention was paid to the effect of electrolytes on electrochemical properties of the nanocomposites,as expected,electrochemical performance was dependent on the nature of the electrolyte,and the neutral electrolytes containing alkali metal ions were found to be very suitable for GS/PPy *** with the pure PPy,the nanocomposite possessed larger specific capacitance and lower internal impedance,indicating that the nanocomposite can be a promising candidate as electrode material for supercapacitors.

关键词： nanocomposites graphene polypyrrole electrochemical property electrolyte

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

Cellulose nanocrystals as green fillers to improve crystallization and hydrophilic property of poly(3-hydroxybutyrate-co-3-hydroxyvalerate)

引用

Progress in Natural science:materials International 2011年第6期21卷 478-484页

作者： Hou-yong YU~(1,2),Zong-yi QIN~1,Zhe ZHOU~2 1.State Key Laboratory for Modification of Chemical Fibers and Polymer materials, donghua university,shanghai 201620,china 2.college of material science and engineering,donghua university,shanghai 201620,china [a] State Key Laboratory for Modification of Chemical Fibers and Polymer materials Donghua University Shanghai 201620 China [b] college of material science and engineering Donghua University Shanghai 201620 China

The green nanocomposites of poly(3-hydroxybutyrate-co-3-hydroxyvalerate)(PHBV) with various cellulose nanocrystals (CNCs) contents were prepared by solution casting *** effects of CNCs on the crystallization behavior,spherulitic morphology,crystal structure and hydrophilic property of PHBV were studied by differential scanning calorimeter(DSC),polarized optical microscope(POM),wide-angle X-ray diffraction(WAXD) and static water contact angle *** is found that the CNCs act as an effective nucleation agent for crystallization of PHBV,inducing an increase in the melt crystallization temperature of the nanocomposites.A study of the non-isothermal crystallization kinetics further illustrated that overall crystallization rate of PHBV in the nanocomposites was faster than that of neat PHBV,but exhibited a decrease in the crystallinity and the spherulite size of PHBV. Furthermore,the contact angle decreased from 60.1°for neat PHBV to 32.5°for the nanocomposites with 10%CNCs(mass fraction).

关键词： nanocomposites poly(3-hydroxybutyrate-co-3-hydroxyvalerate) cellulose nanocrystals crystallization behavior hydrophilic property

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

Optical and acoustic phonon modes confined in gallium phosphide nanoparticles

引用

Rare Metals 2010年第6期29卷 561-566页

作者： ZHANG Zhaochun and ZHANG Neng School of material science and engineering,shanghai university,shanghai 200072,china School of material science and engineering Shanghai University Shanghai China

The main aim of this paper is to discuss the confinement effects on the optical and acoustic phonon vibrational modes in gallium phosphide（GaP） nanoparticles（cylindric grain）.The Raman scattering from the GaP nanoparticles was *** was found that the red-shifts of the longitudinal optical（LO） mode and transverse optical（TO） mode were 15 cm？1 and 13.8 cm？1,*** is generally accepted that the red-shifts of the optical phonon modes are due to the presence of smaller nanosized particles（～1.2 nm） acting as the nanoclustered building blocks of the GaP *** the low frequency Raman spectrum,a set of Stokes lines with almost the same spacing was clearly *** scattering feature originates from the discrete phonon density of states of the nanoclustered building *** to Lamb＇s vibrational theory,the Raman shift wavenumbers of the spheroidal mode and torsional mode of the lowest energy surface modes for the nanoclustered building blocks were *** agreement can be achieved between the calculated results and the observed scattering *** results indicate that the corresponding Raman peaks are due to scattering from the localized acoustic phonons in the nanoclustered building blocks in the GaP nanoparticles.

关键词： spectroscopy phonon mode Raman scattering gallium phosphide nanoparticles confinement effects

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

A VARIATIONAL MODEL FOR 2-D MICROPOLAR BLOOD FLOW

引用

Journal of Hydrodynamics 2003年第3期15卷 119-121页

作者： He Ji-huan college of science, shanghai donghua university, shanghai 200051, china, college of science Shanghai Donghua University Shanghai 200051 China

The micropolar fluid model is an essential generalization of thewell-established Navier-Stokes model in the sense that it takes into account the microstructure ofthe fluid. This paper is devolted to establishing a var... 详细信息

关键词： micropolar flow blood flow variational principle semi-inverse method

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

Effect of Process Factors on Microstructure of Semisolid Continuous Casting Billets

引用

International Journal of Minerals,Metallurgy and materials 2000年第4期14卷 242-245页

作者： Shuming Xing, Qijie Zhai, Hanqi Hu ( Department of Mechanical engineering, Tsinghua university, Beijing 100084, china School of material science and engineering, shanghai university, shanghai 200072, china material science and engineering School, Univer Department of Mechanical engineering Tsinghua University Beijing 100084 China School of material science and engineering Shanghai University Shanghai 200072 China material science and engineering School University of Science and Technology Beijing Beijing 100083 China

Semisolid continuous casting (SSCC) is a new technology to produce billets for semisolid metal forming (SSMF). The effect of process factors, such as pouring temperature, stirring rate, preheating temperature and thermal conductivity of stirring chamber, on the microstructure of SSCC billets was studied by means of the factorial experimental method. The results show that the microstructure of SSCC billets can be controlled by the above-mentioned four process factors. In order to obtain fine and rounded granular grains in an SSCC billet, the pouring temperature, preheating temperature and stirring rate should be kept in a moderate range, and the thermal conductivity of stirring chamber should be high. The regression equations with the process factors connecting the microstructure was also set up based on experimental data.

关键词： semisolid metal continuous casting process factors microstructure Metallurgy

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

Biomimetic mineralization synthesis of hydroxyapatite bacterial cellulose nanocomposites

引用

Progress in Natural science:materials International 2011年第6期21卷 472-477页

作者： Na YIN,Shi-yan CHEN,Yang OUYANG Lian TANG,Jing-xuan YANG,Hua-ping WANG college of materials science and engineering,donghua university,shanghai 201620,china college of materials science and engineering Donghua University Shanghai 201620 China

Hydroxyapatite(HAp)/bacterial cellulose(BC) nanocomposites were prepared by an optimal biomimetic mineralization synthesis approach for bone tissue engineering *** with ultrafine three dimensional network was negatively charged by the adsorption of polyvinylpyrrolidone(PVP) to initiate the nucleation of *** HAp was grown in vitro along the nanofiber network of BC via dynamic simulated body fluid(SBF) *** was found that rod-like HAp particles in the nano-scale (100-200 nm) homogeneously deposited on the surface of ***-Fourier Transform Infrared Spectroscopy(ATR-FTIR) results showed that carbonate-containing HAp crystals resembling natural bones were formed by biomimetic mineralization method. Moreover,the amount of HAp observed increased with increasing mineralization *** the Ca/P overall ratio ranged from 1.37 to *** results from Inductively Coupled Plasma Atomic Emission Spectroscopy(ICP-AES) indicated that PVP treatment enhanced the apatite nucleation ability of BC with higher HAp deposit amount.

关键词： bacterial cellulose hydroxyapatite nanocomposites polyvinylpyrrolidone biomimetic mineralization

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

Theoretical analysis of alloy multiplying factor by the empirical electron theory of solids and molecules

引用

science china(Technological sciences) 2007年第6期50卷 807-814页

作者： SONG YuePeng1,2, LIU GuoQuan2, LI ZhiLin3, FENG ChengMing1 1 Mechanical and Electronic engineering college, Shandong Agricultural university, Tai’an 271018, china 2.college of materials science and engineering, university of science and Technology, Beijing 100083, china 3 college of material science and engineering, Beijing university of Chemical Technology, Beijing 100029, china Mechanical Electronic engineering college Shandong Agricultural University Tai’an 271018 China college of materials science engineering University of Science Technology Beijing 100083 China college of material science engineering Beijing University of Chemical Technology Beijing 100029 China

By introducing the distribution probability of structural units in austenite contain- ing alloying elements and considering its effects on phase transformation, this paper establishes a calculation model of distribution probability of structural units. A new valence electron structure (VES) parameter-transformation effect coefficient of alloying elements (HL), is defined and then studied both theoretically and ex- perimentally. The relationship between the parameter HL and the multiplying factor (the quenching capability factor) of alloying elements is studied. The results indi- cate that the two parameters (HL and the quenching capability factor) have the same variation characteristic and substance feature. Therefore, the multiplying factor virtually expresses the relative quantity of structural units in the alloying elements-containing austenite.

关键词： multiplying factor (the quenching capability factor), empirical electron theory of solids and molecules, transformation effect coefficient of alloying elements, structural units in austenite containing alloying elements

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

Research on Digitalization of High Frequency Microplasma Arc Welding Machine with Small Welding Current

引用

稀有金属材料与工程 2011年第S4期40卷 79-83页

作者： He Jianping1,Huang Chen1,Jiao Fujie1,You Zhichun2 1college of materials engineering,shanghai university of engineering science,shanghai 201620,china2shanghai WTL Welding Equipment Manufacture Co.Ltd.,shanghai 201620,china shanghai Univ Engn Sci Coll Mat Engn Shanghai 201620 Peoples R China shanghai WTL Welding Equipment Mfg Co Ltd Shanghai 201620 Peoples R China

The problem of digital controlling of high frequency microplasma arc welding machine has been solved through Fujitsu 16-bits single-chip processor *** welding power sources and their control systems,digital sequential control system,and digital man-machine interaction system were included in digital microplasma arc welding machine ***,which is about digital sequential control system,digital man-machine interaction system,digital controller and its interface,and controlling software program,were *** has been showed that full digitalization of high frequency microplasma arc welding machine was fulfilled,minimum welding current of the machine is 0.05A,and arc is stable and can been started unfailingly.

关键词： digitalization microplasma arc welding machine single-chip processor

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

Size-controlled and large-scale synthesis of organic-soluble Ag nanocrystals in water and their formation mechanism

引用

Progress in Natural science:materials International 2011年第6期21卷 447-454页

作者： Yu-yuan SHI,Bin SUN,Zhe ZHOU,Yong-tao WU,Mei-fang ZHU State Key Laboratory for Modification of Chemical Fibers and Polymer materials, college of material science and engineering,donghua university,shanghai 201620,china State Key Laboratory for Modification of Chemical Fibers and Polymer materials College of Material Science and Engineering Donghua University Shanghai 201620 China

Organic-soluble Ag nanocrystals(NCs) with tunable sizes in the range from 5.4 to 22.1 nm were synthesized by a facile, reproducible and easily scaled up route using water as solvent in the presence of oleic acid and an *** synthetic Ag NCs exhibits excellent hydrophobicity and can be well re-dispersed in various non- or weak-polar *** tunable sizes of the Ag NCs were achieved by simply adjusting the initial precursor ***-scale synthesis of the Ag NCs was realized at a high AgNO3concentration(0.4 mol/L).As much as 16.2 g highly uniform organic-soluble Ag NCs with 5 nm average diameter can be readily synthesized at low cost in a single reaction only using 400 mL water as solvent,which is adaptable to the industrial scale *** structure of the obtained Ag NCs was investigated in detail by X-ray diffractometry,transmission electron microscopy,Fourier transform infrared and thermal gravimetric analysis *** results reveal that the surface of the organic-soluble Ag NCs is coated with the monolayer surfactants consisting of oleic acid and the *** addition,on the basis of the sufficient evidences,a proposed mechanism based on the "bilayer surfactant-controlled reaction" successfully demonstrates the formation of high quality organic-soluble Ag NCs in the aqueous solution.

关键词： organic-soluble Ag nanocrystals large-scale size-controlled synthesis formation mechanism

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

The Properties of Native Silk Fibroin (SF) Solution/Gel from Bombyx mori Silkworms during the Full Fifth Instar Larval Stage

引用

Journal of Wuhan university of Technology(materials science) 2011年第2期26卷 263-269页

作者：王洪 Key Laboratory of Textile science & Technology Ministry of EducationDonghua University

The properties of native silk fibroin （SF） solution in the gland of silkworms during the full fifth instar larval stage were examined in an attempt to elucidate the mechanism of natural silk spinning in the *** flow and gelation behavior,birefringence phenomenon,rheological properties,specific viscosity and conformation of SF solutions from the gland of silkworms were measured by polarized light microscope,HAKKE rheometer,Ubbelohde viscometer and Solid-state 13C NMR,*** comparing their properties with regenerated SF solutions from natural silk fibers,it is believed that there exists a progressive maturation process favorable to spin silk fibers with excellent properties from native SF solution and a weak bonded and highly oriented SF gel network with SF molecules partly extended in α-helix conformation is formed in the middle section of the gland of *** suggests that a biomimetic maturation process for making spinnable solution might be necessary for artificial silk fiber spinning in order to obtain improved fiber properties.

关键词： silk fibre spin viscosity sol/gel

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：