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Frontiers of Chemical Science and Engineering 2007年第2期1卷 208-215页

作者： SHANG Weijuan WANG Daxin WANG Xiaolin Department of Chemical Engineering Tsinghua UniversityBeijing 100084China

Although there is a voluminous literature on the determination of structural parameters(the pore radius,the ratio of membrane porosity to membrane thickness)of a nanofiltration(NF)membrane and its separation perfor-mance(such as the rejection and the permeation flux)by the simplified Teorell-Meyer-Sievers(TMS)model,little of this research comments on other theories and the consequences of linking modeling evaluation to technological *** used to predict the separation performance of an NF membrane usually include:the non-equilibrium thermo-dynamic model,the pore model,the space charge model,the TMS model,the electrostatic and steric-hindrance model,and the semiempirical *** the article,we briefly trace the origins or the general ideas of the above-mentioned *** there,recent researches on the characterization of mem-brane structural parameters and electrical properties(such as the surface charge density qw)are *** then turn to research on the separation performance of an NF membrane for single-component solutions of inorganic electrolytes,neutral organic solutions,and a mixture solution of electro-lytes or that of an electrolyte and neutral organic ***,we outline the applications of NF technology in the processes of product separation and conclude with a discussion on the role of models in such applications.

关键词： nanofiltration membrane Teorell-Meyer-Sievers model electrical properties

Preparation of low-temperature sintered high conductivity inks based on nanosilver self-assembled on surface of graphene

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Journal of Central South University 2019年第11期26卷 2953-2960页

作者： LIU Piao HE Wen-qiang LU An-xian Hunan LEED Electronic Ink Co. Ltd.Zhuzhou 412007China School of Materials Science and Engineering Central South UniversityChangsha 410083China

Finer nanoplates of silver are prepared by self-assembly on the surface of graphene,and the low-temperature sintered high conductivity ink containing the silver nanoplates is *** importantly,graphene is added to the solution before the chemical reduction reaction ***,it is found that silver nanoplates have self-assembly phenomenon on the surface of ***,the Ag nano hexagonal platelets(AgNHPs)with small particle sizes(10 nm),narrow distribution and good dispersion are ***,smaller sizes(10 nm)and narrower particle size distribution of AgNHPs particles can be easily controlled by using this ***,the conductivity of the ink is *** example,when the printed patterns were sintering at 150℃,the resistivity of the ink(GE:0.15 g/L)reached the minimum value of 2.2×10^-6 *** the resistivity value was 3.7×10^-6Ωcm,when it was sintered at 100℃ for 30 *** conductive ink prepared can be used for the field of printing electronics as ink-jet printing ink.

关键词： Ag nanoparticles graphene self-assembly conductive ink electrical properties

Effects of ply-orientation on microstructure and properties of super-aligned carbon nanotube reinforced copper laminar composites

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Transactions of Nonferrous Metals Society of China 2017年第8期27卷 1747-1758页

作者： Jing SHUAI Lun-qiao XIONG Lin ZHU Wen-zhen LI School of Materials Science and Engineering Tsinghua University Beijing 100084 China Tsinghua-Foxconn Nanotechnology Research Center Tsinghua University Beijing 100084 China

The super-aligned carbon nanotube(SACNT)films reinforced copper(Cu)laminar composites with different orientationsof CNT ply were fabricated by *** results show that the tensile strength and yield strength of cross-ply compositewith5.0%(volume fraction)of SACNT reach maximum of336.3MPa and246.0MPa respectively,increased by74.0%and124.5%compared with pure Cu prepared with the same ***,the electrical conductivities of all the prepared composites areover75%*** result of TEM analysis shows that the size of Cu grain and the thickness of twin lamellae can be reduced byadding SACNT,and the refining effect in cross-ply composites is more significant than that in unidirectional ply *** strength of the Cu/SACNT composites comes from not only the reinforcing effect of SACNT films but also the additionalstrengthening of the Cu grain refinement caused by CNT orientation.

关键词： copper laminar composite super-aligned carbon nanotubes reinforcement ply-orientation mechanical properties electrical properties microstructure

Crystallization kinetics and temperature dependence of energy storage properties of niobate glass-ceramics

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Transactions of Nonferrous Metals Society of China 2014年第3期24卷 729-735页

作者：刘涛涌陈国华宋俊袁昌来桂林电子科技大学材料科学与工程学院桂林541004 桂林电子科技大学广西信息材料重点实验室桂林541004

Glass-ceramic materials of strontium barium niobate system were prepared through a melt-quenching method. The effects of crystallization temperature on the mierostructure, dielectric property, breakdown strength and energy storage density of barium strontium niobate glass-ceramics were studied. The crystallization mechanism of the glass-ceramics was discussed and should be one-dimensional interfacial growth. The results indicate that the breakdown strength remarkably increases with the increase of crystallization temperature. The glass-ceramic heat treated at 900 ℃ was found to possess optimal properties with breakdown strength of 1300 kV/cm and energy storage density of 2.8 J/cm3, which is promising dielectric materials for high energy storage density dielectrics.

关键词： glass-ceramics dielectrics crystallization electrical properties

聚氨酯海绵中碳纳米管与各向异性形状Ni的协同效应增强电磁干扰屏蔽性能

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Science China Materials 2023年第7期66卷 2803-2811页

作者：程浩然潘亚敏王铁成周洋秦怡静刘春太申长雨刘宪虎 College of Materials Science and Engineering National Engineering Research Center for Advanced Polymer Processing TechnologyKey Laboratory of Advanced Material Processing&Mold(Ministry of Education)Zhengzhou UniversityZhengzhou 450002China Institute of Polymer Materials Friedrich-Alexander-University Erlangen-NurembergMartensstr.791058ErlangenGermany Center for Engineering Materials and Reliability Guangzhou HKUST Fok Ying Tung Research InstituteGuangzhou 511458China

巧妙的微观结构设计和合适的多组分策略仍然是高效吸收型电磁干扰屏蔽材料在轻质、低填充水平和薄样品厚度方面的挑战.本文基于独特的屏蔽胶囊结构,采用浸渍法制备了柔性水性聚氨酯/介电碳纳米管/磁各向异性镍(链或花)电磁屏蔽复合海绵... 详细信息

巧妙的微观结构设计和合适的多组分策略仍然是高效吸收型电磁干扰屏蔽材料在轻质、低填充水平和薄样品厚度方面的挑战.本文基于独特的屏蔽胶囊结构,采用浸渍法制备了柔性水性聚氨酯/介电碳纳米管/磁各向异性镍(链或花)电磁屏蔽复合海绵.结果表明,增加镍(花状或链状)填料的含量可显著提高复合材料的导电性和电磁干扰屏蔽性能.水性聚氨酯/碳纳米管/8 wt%镍花-三聚氰胺海绵和水性聚氨酯/碳纳米管/8 wt%镍链-三聚氰胺海绵的电磁屏蔽性能分别为42.8和46.7 dB,优于仅含碳纳米管的复合海绵.碳纳米管与镍(花状或链状)之间的协同作用意味着复合海绵的屏蔽电磁干扰的主要机制来自于吸收过程.重要的是,在水性聚氨酯层的保护下,复合材料在强烈的物理和化学损伤下仍然表现出良好的电磁屏蔽性能.这项工作为设计新颖、轻量化和高效的电磁屏蔽复合材料提供了一种简单的协同策略,在便携式和可穿戴电子设备中显示出巨大的应用前景.

关键词： carbon nanotubes anisotropy-shaped Ni polymer-matrix composites electrical properties electromagnetic interference shielding

Synergetic influence of ex-situ camphoric carbon nano-grafting on lithium titanates for lithium ion capacitors

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Journal of Energy Chemistry 2015年第3期24卷 337-345页

作者： Amruthalakshmi Vijayakumar Ranjusha Rajagopalan Anoop S.Sushamakumariamma Jickson Joseph Amrutha Ajay Shantikumar V Nair Deepak Krishna M.S Avinash Balakrishnan Nanosolar Division Amrita Center for Nanosciences Institute for Superconducting & Electronic Materials (ISEM) University of Wollongong

The present study provides detailed experimental results on the synthesis and characterization of carbonized lithium titanate spinel（LTO） composites as electrode materials for lithium ion *** LTO particles were grafted with a porous carbon layer obtained from the pyrolysis of *** graphitic nature of the carbon was confirmed through Raman *** relative contributions from the capacitive and diffusion controlled processes underlying these electrodes were mathematically *** transport mechanism underlying these electrodes was determined by measuring the work functions（φ） of LTO and carbon grafted LTO using ultraviolet photoelectron *** carbon grafted LTO composites exhibited an energy density of 330 m Wh L-1and a peak power density of 2.8 k W L-1,when employed as electrodes in coin cells with excellent cycling stability at the end of 4000 cycles.

关键词： functional composites capacitors electrical properties lithium ion energy storage

Ultrasonic synthesis of Zn-doped CdO nanostructures and their optoelectronic properties

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Transactions of Nonferrous Metals Society of China 2018年第11期28卷 2256-2265页

作者： Milad KAVAKEBI Farid JAMALI-SHEINI Department of Materials Science and Engineering Ahvaz BranchIslamic Azad UniversityAhvazIran Advanced Surface Engineering and Nano Materials Research Center Department of PhysicsAhvaz BranchIslamic Azad UniversityAhvazIran

The effect of Zn dopant on the growth of cadmium oxide （CdO） nanostructures through a sonochemical method wasinvestigated. The X-ray diffraction （XRD） patterns of the nanoparticles show CdO cubic structures for the produced samples. Fieldemission scanning electron microscope （FESEM） images reveal that morphologies of the samples change, when they are doped withZn atoms, and their sizes reduce. Room temperature photoluminescence （PL） and UV-Vis spectrometers were used to study opticalproperties of the samples. Evaluation of optical properties indicates that different emission bands result from different transitions andthe value of CdO energy band gap increases due to doping. Studies of electrical properties of the nanostructures demonstrate that Zndopant enhances electrical conductivity and photocurrent generation as the result of light illumination on the nanostructures due toimproved density of photo-generated carriers. Considering the obtained outcomes, Zn dopant can alter the physical property of theCdO nanostructures.

关键词： Zn-doped CdO nanostructures ultrasonication method optical properties electrical properties

Sol-gel auto-combustion synthesis of K_xNa_(1-x)NbO_3 nanopowders and ceramics: Dielectric and piezoelectric properties

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Transactions of Nonferrous Metals Society of China 2018年第9期28卷 1801-1807页

作者： Hua-lei CHENG Jian XIAO Peng GAO Yun-yun YAN Shuan-ping GAO Hong-liang DU Key Laboratory of Phytochemistry of Shaanxi Province College of Chemistry and Chemical EngineeringBaoji University of Arts and SciencesBaoji 721013China State Key Laboratory of Solidification Processing School of Materials Science and Engineering Northwestern Polytechnical UniversityXi’an 710072China Science College Air Force Engineering UniversityXi’an 710051China

The KxNa1-xNbO3 nanopowders with cubic-like morphology and an average size of about 50 nm were synthesized by sol-gel auto-combustion *** then,the ceramics were prepared and the phase transition,microstructure and electrical properties of the KxNa1-xNbO3 ceramics were *** perovskite phases of the KxNa1-xNbO3 ceramics were confirmed by XRD patterns and the K0.50Na0.50NbO3 ceramics show the coexistence of orthorhombic and monoclinic *** micrographs show that all samples have bimodal grain size distributions and the number of the small grains decrease with increasing K+content in the bimodal grain size distribution *** K0.50Na0.50NbO3 ceramics with the uniform grain size and the maximum density show excellent electrical properties withεr=467.40,tanδ=0.020,d33=128 pC/N and kp=0.32 at the room temperature,demonstrating that the properties of the K0.50Na0.50NbO3 powers prepared by sol-gel auto-combustion are excellent and the ceramics are promising lead-free piezoelectric materials.

关键词： sol-gel auto-combustion KxNa1-xNbO3 phase transition microstructure electrical properties

Effect of small changes in sintering temperature on varistor properties and degradation behavior of V-Mn-Nb-Gd co-doped zinc oxide ceramics

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Transactions of Nonferrous Metals Society of China 2015年第4期25卷 1176-1184页

作者： C.W.NAHM Semiconductor Ceramics Laboratory Department of Electrical Engineering Dongeui UniversityBusan 614-714 Korea

The effect of small changes in sintering temperature on microstructure, electrical properties, dielectric characteristics, and degradation behavior of V-Mn-Nb-Gd co-doped zinc oxide ceramics was investigated. With the increase of sintering temperature, the densities of the sintered pellets decreased from 5.54 to 5.42 g/cm3 and the average grain size increased from 4.1 to 11.7 μm. The breakdown field(E1 m A) decreased noticeably from 7138 to 920 V/cm with the increase of sintering temperature. The varistor ceramics sintered at 900 ℃ exhibited excellent nonohmic properties, which were 66 for the nonohmic coefficient and 77 μA/cm2 for the leakage current density. Concerning stability, the varistors sintered at 900 ℃ exhibited the strongest accelerated degradation characteristics, with ΔE1 mA =-9.2% for DC accelerated degradation stress of 0.85 E1 m A at 85 °C for 24 h.

关键词： ZnO-V2O5-based ceramics sintering electrical properties degradation behavior varistor

Electrophysical properties of ceramic-polymer composite films as function of sintering temperature

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Transactions of Nonferrous Metals Society of China 2018年第3期28卷 495-501页

作者： Sajedeh MOHAMMADI AREF Mohammad GHAFOURI Faculty of Physics University of Tabriz Physics Department Shabestar Branch Islamic Azad University

The effect of changes in sintering temperature on electrical properties and microstructure of ZnO?polyaniline?polyethylene composite ceramics,prepared in disk form at the pressure of 60 MPa and at five different temperatures,has been *** sintering temperature from 30 to 120°C noticeably reduces breakdown voltage from 830 to 610 *** increase in sintering temperature causes breakdown voltage to *** voltage barrier height behaves differently when sintering temperature increases,which is in contrast to breakdown voltage *** samples have a very low leakage current,a factor which indicates low *** again,the higher the sintering temperature gets,the less the nonlinear coefficient *** addition,each sample has hysteresis which decreases through increase of sintering temperature up to 120°*** increase in sintering temperature,however,causes the hysteresis loop to *** UV spectra of the samples,it is revealed that there are three impurity levels whose behaviors against sintering temperature are *** of composite samples by scanning electron microscopy indicates that their microstructure consists of grains and grain *** of grain boundaries is the main responsible factor for these changes in varistor characteristic as a function of sintering temperature.

关键词： ZnO electrical properties sintering temperature varistor composite microstructure