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Force and impulse multi-sensor based on flexible gate dielectric field effect transistor
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作者 Chao Tan Junling Lü +3 位作者 Chunchi Zhang Dong Liang Lei Yang Zegao Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期214-220,共7页
Nowadays,force sensors play an important role in industrial production,electronic information,medical health,and many other fields.Two-dimensional material-based filed effect transistor(2D-FET)sensors are competitive ... Nowadays,force sensors play an important role in industrial production,electronic information,medical health,and many other fields.Two-dimensional material-based filed effect transistor(2D-FET)sensors are competitive with nano-level size,lower power consumption,and accurate response.However,few of them has the capability of impulse detection which is a path function,expressing the cumulative effect of the force on the particle over a period of time.Herein we fabricated the flexible polymethyl methacrylate(PMMA)gate dielectric MoS_(2)-FET for force and impulse sensor application.We systematically investigated the responses of the sensor to constant force and varying forces,and achieved the conversion factors of the drain current signals(I_(ds))to the detected impulse(I).The applied force was detected and recorded by I_(ds)with a low power consumption of~30 nW.The sensitivity of the device can reach~8000%and the 4×1 sensor array is able to detect and locate the normal force applied on it.Moreover,there was almost no performance loss for the device as left in the air for two months. 展开更多
关键词 flexible gate dielectric transistor force sensor impulse sensor force sensor array
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Alternative Strategy for Development of Dielectric Calcium Copper Titanate‑Based Electrolytes for Low‑Temperature Solid Oxide Fuel Cells
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作者 Sajid Rauf Muhammad Bilal Hanif +8 位作者 Zuhra Tayyab Matej Veis MAKYousaf Shah Naveed Mushtaq Dmitry Medvedev Yibin Tian Chen Xia Martin Motola Bin Zhu 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期310-332,共23页
The development of low-temperature solid oxide fuel cells(LT-SOFCs)is of significant importance for realizing the widespread application of SOFCs.This has stimulated a substantial materials research effort in developi... The development of low-temperature solid oxide fuel cells(LT-SOFCs)is of significant importance for realizing the widespread application of SOFCs.This has stimulated a substantial materials research effort in developing high oxide-ion conductivity in the electrolyte layer of SOFCs.In this context,for the first time,a dielectric material,CaCu_(3)Ti_(4)O_(12)(CCTO)is designed for LT-SOFCs electrolyte application in this study.Both individual CCTO and its heterostructure materials with a p-type Ni_(0.8)Co_(0.15)Al_(0.05)LiO_(2−δ)(NCAL)semiconductor are evaluated as alternative electrolytes in LT-SOFC at 450–550℃.The single cell with the individual CCTO electrolyte exhibits a power output of approximately 263 mW cm^(-2) and an open-circuit voltage(OCV)of 0.95 V at 550℃,while the cell with the CCTO–NCAL heterostructure electrolyte capably delivers an improved power output of approximately 605 mW cm^(-2) along with a higher OCV over 1.0 V,which indicates the introduction of high hole-conducting NCAL into the CCTO could enhance the cell performance rather than inducing any potential short-circuiting risk.It is found that these promising outcomes are due to the interplay of the dielectric material,its structure,and overall properties that led to improve electrochemical mechanism in CCTO–NCAL.Furthermore,density functional theory calculations provide the detailed information about the electronic and structural properties of the CCTO and NCAL and their heterostructure CCTO–NCAL.Our study thus provides a new approach for developing new advanced electrolytes for LT-SOFCs. 展开更多
关键词 LT-SOFCs dielectric CaCu_(3)Ti_(4)O_(12) Semiconductor Ni_(0.8)Co_(0.15)Al_(0.05)LiO_(2−δ) Ionic conductivity Heterostructure electrolyte
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Effect of temperature on dielectric property and microwave heating behavior of low grade Panzhihua ilmenite ore 被引量:10
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作者 刘晨辉 张利波 +4 位作者 彭金辉 刘秉国 夏洪应 顾晓春 史谊峰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第11期3462-3469,共8页
The permittivity of low grade Panzhuhua ilmenite ore at 2.45 GHz in the temperatures from 20 ℃ up to 100 ℃ was measured using the technology of open-ended coaxial sensor combined with theoretical computation. The re... The permittivity of low grade Panzhuhua ilmenite ore at 2.45 GHz in the temperatures from 20 ℃ up to 100 ℃ was measured using the technology of open-ended coaxial sensor combined with theoretical computation. The results show that both the real (ε′) and imaginary (ε′) part of complex permittivity (ε′-jε′) of the ilmenite significantly increase with temperature. The loss tangent (tanδ) is a quadratic function of temperature, and the penetration depth of ilmenite decreases with temperature increase from 20 ℃to 100 ℃ The increase of the sample temperature under microwave radiation displays a nonlinear relationship between the temperature (T) and microwave heating time (t). The positive feedback interaction between complex permittivity and sample temperature amplifies the interaction between ilmenite and the microwave radiation. The optimum dimensions for uniform heat deposition vary from 10 cm to 5 cm (about two power penetration depths) in a sample being irradiated from both sides in a 2.45 GHz microwave field when temperature increases from room temperature to 100 ℃ 展开更多
关键词 dielectric properties Panzhihua ilmenite low grade microwave heating temperature increase
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Broad Microwave Dielectric Property of Single-walled Carbon Nanotube Composites 被引量:1
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作者 Junhua WU 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2008年第4期661-666,共6页
Microwave dielectric measurements over the broad bandwith of 10 MHz to 20 GHz were conducted on composites comprising bundles of single-walled carbon nanotubes (SWNT) embedded in an epoxy matrix, in comparison to th... Microwave dielectric measurements over the broad bandwith of 10 MHz to 20 GHz were conducted on composites comprising bundles of single-walled carbon nanotubes (SWNT) embedded in an epoxy matrix, in comparison to the nano-graphite and MWNT. It is found that both relative real and imaginary permittivity of the nanocomposites are strong functions of the SWNT concentration, showing large, wide dielectric and electrical response. Distinct resonance around 1.5 GHz is observed at high SWNT concentrations, accompa- nied by the downshift of the resonance frequency with increasing concentration. Largely, the SWNT-epoxy composites share the behavior of the MWNT owing to structural similarity, much more effective than the nano-graphite. The remarkable, broadband dielectric and electrical properties of the nanotubes acquired in the work originate from their unique seamless graphene architectures, modeled by two major contributions, dielectric relaxation/resonance and electronic conduction, which is substantiated by the agreement between theoretical analysis and experimental results. The carbon nanotube composites are prospective for microwave applications and offer experimental evidence for fundamental studies in low-dimensional systems. 展开更多
关键词 Single-walled carbon nanotube dielectric properties MICROWAVE COMPOSITE
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Microfluidic temperature sensor based on temperature-dependent dielectric property of liquid 被引量:3
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作者 Qi Liu Yu-Feng Yu +1 位作者 Wen-Sheng Zhao Hui Li 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第1期181-185,共5页
We propose a low-cost compact microfluidic temperature sensor by virtue of the temperature-dependent permittivity of liquid.The sensor is composed of a coplanar waveguide(CPW)transmission line loaded with three resona... We propose a low-cost compact microfluidic temperature sensor by virtue of the temperature-dependent permittivity of liquid.The sensor is composed of a coplanar waveguide(CPW)transmission line loaded with three resonators and a microfluidic plate with three channels.The resonant frequency of each resonator relies on the temperature-dependent dielectric property of liquid in corresponding channel,which therefore can be used to extract the temperature.The proposed sensor features a compact size and low cost since it requires only micro fluid volume instead of additional electronic components to produce significant frequency shift with changing temperature.Moreover,it exhibits decent accuracy and stability in a temperature sensing range from 30℃ to 95℃.A theoretical analysis of the sensor is provided,followed by the detailed characterization method,and a prototype is designed,manufactured,and measured to verify the theoretical analysis. 展开更多
关键词 MICROFLUIDICS SENSORS PERMITTIVITY dielectric liquid
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Improving the Interfacial Mechanical Property of Fiber Reinforced Cement with Dielectric Barrier Discharge 2: Morphological and Compositional Changes of the Fiber Surface 被引量:1
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作者 丁 可 胡群华 谢涵坤 《Journal of Donghua University(English Edition)》 EI CAS 2001年第1期32-37,共6页
The morphological and compositional changes of the PP fibers pretreated with dielectric barrier discharge (DBD)are investigated with SEM, XPS and IR. The result shows that the etching effect is the main reason for the... The morphological and compositional changes of the PP fibers pretreated with dielectric barrier discharge (DBD)are investigated with SEM, XPS and IR. The result shows that the etching effect is the main reason for the improvement of the result of pull-out test of the fibercement composite reported in a previous paper and the oxidation of the fiber surface also favors the adhesion between the fiber and the matrix. 展开更多
关键词 dielectric BARRIER discharge surface modification morphological and compositional changes.
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Electrical conductivity and dielectric property of fly ash geopolymer pastes
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作者 Sakonwan Hanjitsuwan Prinya Chindaprasirt Kedsarin Pimraksa 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2011年第1期94-99,共6页
The electrical conductivity and dielectric property of fly ash geopolymer pastes in a frequency range of 100 Hz-10 MHz were studied.The effects of the liquid alkali solution to ash ratios(L/A) were analyzed.The mine... The electrical conductivity and dielectric property of fly ash geopolymer pastes in a frequency range of 100 Hz-10 MHz were studied.The effects of the liquid alkali solution to ash ratios(L/A) were analyzed.The mineralogical compositions and microstructures of fly ash geopolymer materials were also investigated using X-ray diffraction(XRD) and scanning electron microscopy(SEM).The 10 mol sodium hydroxide solution and sodium silicate solution at a sodium silicate-to-sodium hydroxide ratio of 1.0 were used in making geopolymer pastes.The pastes were cured at 40℃.It is found that the electrical conductivity and dielectric constant are dependent on the frequency range and L/A ratios.The conductivity increases but the dielectric constant decreases with increasing frequency. 展开更多
关键词 fly ash inorganic polymers dielectric properties electrical conductivity
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Preparation, Characterization and Dielectric Property of Sr_5LaTi_3Nb_7O_(30) Ceramic
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作者 卓蓉晖 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2004年第3期48-50,共3页
Sr-5LaTi-3Nb-7O- 30 ceramic was prepared by the conventional high temperature solid-state reaction route. The sintered samples were characterized by X-ray diffraction, scanning electron microscopy (SEM), differential... Sr-5LaTi-3Nb-7O- 30 ceramic was prepared by the conventional high temperature solid-state reaction route. The sintered samples were characterized by X-ray diffraction, scanning electron microscopy (SEM), differential thermal calorimetry (DSC) and dielectric measurements.The results show Sr-5LaTi-3Nb-7O- 30 belongs to paraelectric phase of filled tetragonal TB structure at room temperature, and undergoes a diffuse phase transition in the temperature range of -54-34 ℃.And Sr-5LaTi-3Nb-7O- 30 ceramic shows a high dielectric constant of 479 with a low dielectric loss of 0.005 at 1MHz. In comparison with Ba-based ceramics with TB structure, the temperature coefficients of the dielectric constant (τ-ε) is significantly reduced. 展开更多
关键词 NIOBATE dielectric properties phase transition tungsten bronze
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Effects of HfO_2 buffer layers on the dielectric property and leakage current of Ba_(0.6)Sr_(0.4)TiO_3 thin films by pulsed laser deposition
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作者 耿彦 程晋荣 +1 位作者 俞圣雯 吴文彪 《Journal of Shanghai University(English Edition)》 CAS 2010年第6期456-459,共4页
Ba0.6Sr0.4TiO3 (BST) thin films with and without HfO 2 buffer layer were fabricated on Pt/Ti/SiO2/Si substrates by pulsed laser deposition. Dependences of HfO 2 thickness on the dielectric property and leakage curre... Ba0.6Sr0.4TiO3 (BST) thin films with and without HfO 2 buffer layer were fabricated on Pt/Ti/SiO2/Si substrates by pulsed laser deposition. Dependences of HfO 2 thickness on the dielectric property and leakage current of BST thin films were focused. The dielectric constant of BST thin films increased and then decreased with the increase of HfO 2 thickness, while the dielectric relaxation was gradually improved. The loss tangent and leakage current under positive bias decreased with the HfO 2 thickness increasing. The leakage current analysis based on the Schottky emission indicated an improvement of the BST/Pt interface with HfO 2 buffer layer. The loss tangent, tunability and figure of merit of optimized HfO 2 buffered BST thin film achieved 0.009 8, 21.91% (E max = 200 kV/cm), 22.40 at 10 6 Hz, respectively. 展开更多
关键词 Ba0.6Sr0.4TiO3 (BST) thin film HfO 2 buffer layer dielectric property leakage current Schottky emission
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Study on Microwave Dielectric Property of Carbon Black and Short Carbon Fibers
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作者 WUHong-huan ZHU Dong-mei LUO Fa ZHOU Wan-cheng WANG Xiao-yan 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2006年第B12期130-133,共4页
Carbon black and carbon fibers of different lengths were introduced in different matrices at different ratios to explore their microwave dielectric properties under 8.2 GHz-12.4 GHz. It is found that the actual dielec... Carbon black and carbon fibers of different lengths were introduced in different matrices at different ratios to explore their microwave dielectric properties under 8.2 GHz-12.4 GHz. It is found that the actual dielectric constants of the samples containing carbon black are in a two-order function of the contents of carbon black (ε', ε"=Av2+Bv+C) and the complex dielectric constants show an obvious frequency response. Of the added fibers of different lengths, the 4 mm-long one could well disperse in the matrices having not only good frequency response, but also larger real parts, imaginary parts and loss values. The imaginary parts and the loss values (tanδ)of the samples with 4 mm-long carbon fibers added increase linearly with the contents of fiber increasing. So it is practicable to adjust the dielectric parameters of the material in a wide range by changing the added amount of carbon black, and the carbon fiber or altering the lengths of the carbon fiber added. 展开更多
关键词 microwave dielectric property short carbon fibers carbon black
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Investigation on dependence of BiFeO_3 dielectric property on oxygen content
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作者 娄艳辉 宋桂林 +1 位作者 常方高 王照奎 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第7期555-558,共4页
The influence of oxygen content on the dielectric property of BiFeO3 ceramics is studied by experiment and firstprinciples calculation. The experimental result demonstrates that the dielectric constant of BiFeO3 is st... The influence of oxygen content on the dielectric property of BiFeO3 ceramics is studied by experiment and firstprinciples calculation. The experimental result demonstrates that the dielectric constant of BiFeO3 is strongly dependent on introduced oxygen and oxygen vacancies. By comparison with BiFeO3, the introduced oxygen and oxygen vacancies can lead to a reduction in dielectric constant of BiFeO5 at a lower frequency. The first-principles calculation also shows a similar result when photon energy is in a range of 2.0-4.1 eV. A likely explanation is that this oxygen content dependence may be ascribed to the distortion of Fe-O octahedron structure due to oxygen vacancies or excess oxygen ions in the crystal structure of BiFeO3. 展开更多
关键词 BIFEO3 dielectric property oxygen content
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Synthesis, Structure and Dielectric Property of Ba_(1- x)Sr_xZr_yTi_(1- y)O_3
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作者 DING Shi-wen ZHAI Yong-qing +2 位作者 ZHANG Xue-jian WANG Hong-ge LIU Hai-yan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1999年第3期267-270,共4页
A sieres of Ba 1- x Sr x Zr y Ti 1- y O 3(0≤ x ≤0.4, 0< y <0.3) solid solutions was synthesized by soft chemical method below 100 ℃. The XRD and cell parameters component figures of the series of the solid so... A sieres of Ba 1- x Sr x Zr y Ti 1- y O 3(0≤ x ≤0.4, 0< y <0.3) solid solutions was synthesized by soft chemical method below 100 ℃. The XRD and cell parameters component figures of the series of the solid solutions powder demonstrate that the compounds are mutually miscible in the solid solutions. Furthermore, the observation through a TEM showed that the product has a shape of uniform, substantially spherical particles with an average particle size of 60 nm in diameter. The result of prepared ceramics shows that after being adulterated with Sr 2+ and Zr 4+ in pure BaTiO 3 phase, the dielectric constant was increased eight times at room temperature, while the dielectric loss was decreased three times. 展开更多
关键词 BaTiO 3 solid solution Chemical adulteraion dielectric property
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Microstructure and Dielectric Property of 3D BNf/Si3N4 Fabricated by CVI Process
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作者 LI Jianping CHENG Laifei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2019年第4期818-823,共6页
As potential wave-transparent materials applied at high temperatures, 3D BNf/Si3N4 ceramic matrix composites were prepared by low pressure chemical vapor infiltration or deposition(LPCVI/CVD) process from SiCl4-NH3-... As potential wave-transparent materials applied at high temperatures, 3D BNf/Si3N4 ceramic matrix composites were prepared by low pressure chemical vapor infiltration or deposition(LPCVI/CVD) process from SiCl4-NH3-H2-Ar gas precursor at 800 oC. The densification process, microstructure and dielectric properties of 3D BNf/Si3N4 composites were investigated. The results indicated that 3D BNf/Si3N4 was successfully fabricated by LPCVI/CVD, with final open porosity of 2.37% and density of 1.89 g/cm3. Densification kinetics of 3D BNf/Si3N4 is a typical exponential pattern. The Si3N4 matrix was uniformly infiltrated into porous BNf preform. The deposited Si3N4 matrix was amorphous by XRD analysis. Introduction of BN fiber into Si3N4 ceramic lowered the permittivity of Si3N4. The fabricated BNf/Si3N4 composites possess low permittivity of 3.68 and low dielectric loss of lower than 0.01, which are independent of temperature below400 oC. Transmission coefficient of BNf/Si3N4 composite is 0.57 and keeps stable below 400 oC. BNf/Si3N4 can be fabricated at low temperature and may be candidates for the microwave transparent materials. 展开更多
关键词 BNf/Si3N4 LPCVI dielectric property high temperature stability
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Dielectric Property Studies of Biologically Compatible Brushite Single Crystals Used as Bone Graft Substitute
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作者 M. P. Binitha P. P. Pradyumnan 《Journal of Biomaterials and Nanobiotechnology》 2013年第2期119-122,共4页
The electrical characterization of bone is essential for the better understanding of the role of electrical stimulation in bone remodeling. Calcium Hydrogen Phosphate Dihydrate or brushite (CaHPO4 2H2O) has been used ... The electrical characterization of bone is essential for the better understanding of the role of electrical stimulation in bone remodeling. Calcium Hydrogen Phosphate Dihydrate or brushite (CaHPO4 2H2O) has been used in bone substitution owing to their fast resorption under physiological condition. Brushite is a suitable matrix for osteoconductive bone grafts. In this work, Calcium Hydrogen Phosphate single crystals have been grown by single diffusion gel growth technique. The powder XRD studies revealed the monoclinic structure of the grown crystals. The vibrational analysis of the crystals is done with FTIR spectroscopy and the major functional groups and their assigned vibrations are discussed. The frequency dependence of dielectric constant and ac conductivity at different temperatures have been studied in detail. This study shows decrease in the dielectric constant with the increase in frequency and temperature. The variation of ac conductivity is found to be increasing with frequency and decreasing with temperature. 展开更多
关键词 BONE GRAFTS BRUSHITE GEL Growth dielectric Properties AC CONDUCTIVITY
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Improving the Interfacial Mechanical Property of Fiber Reinforced Cement with Dielectric Barrier Discharge 1:The Pul - out Test
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作者 丁可 施芸城 谢涵坤 《Journal of China Textile University(English Edition)》 EI CAS 2000年第3期77-79,共3页
The effect of dielectric barrier discharge(DBD)on the interfacial mechanical property of polypropylene fiber reinforced cement is investigated with the aid of single fiber pull out test.The result shows that the DBD t... The effect of dielectric barrier discharge(DBD)on the interfacial mechanical property of polypropylene fiber reinforced cement is investigated with the aid of single fiber pull out test.The result shows that the DBD treatment improved the adhesion between the PP fiber and the surrounding cement matrix considerably without serious aging.Keywords:dielectric barrier discharge,single fiber pull-out test. 展开更多
关键词 dielectric BARRIER discharge single fiber PULLOUT test.
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Analysis on Dynamic Dielectric Recovery and Statistical Property of Vacuum Circuit-Breakers with Multi-Breaks
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作者 廖敏夫 段雄英 邹积岩 《Journal of Beijing Institute of Technology》 EI CAS 2004年第1期103-108,共6页
Based on the dynamic dielectric recovery process in the vacuum gaps in series, investigations were made on post-arc insulation state in double and multi-breaks operation in high voltage power system. From the research... Based on the dynamic dielectric recovery process in the vacuum gaps in series, investigations were made on post-arc insulation state in double and multi-breaks operation in high voltage power system. From the research on the breakdown weak points in high voltage vacuum gaps, their turnout and distribution, some theoretic work were made to set up the models for describing the statistical property of multi-breaks vacuum circuit-breakers' breakdown and post-arc re-strike, which can be used for explaining the mechanism of the improvement in the breaking capacity of multi-breaks units compared with that of single-break ones which have the same equivalent gap length. The advantages of vacuum breakers with multi-breaks are proposed. 展开更多
关键词 multi-breaks dynamic dielectric recovery breakdown weak points
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Solid-state impedance spectroscopy studies of dielectric properties and relaxation processes in Na_(2)O–V_(2)O_(5)–Nb_(2)O_(5)–P_(2)O_(5) glass
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作者 Sara Marijan Luka Pavic 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期186-196,共11页
Solid-state impedance spectroscopy(SS-IS)was used to investigate the influence of structural modifications resulting from the addition of Nb2O5 on the dielectric properties and relaxation processes in the quaternary m... Solid-state impedance spectroscopy(SS-IS)was used to investigate the influence of structural modifications resulting from the addition of Nb2O5 on the dielectric properties and relaxation processes in the quaternary mixed glass former(MGF)system 35Na_(2)O–10V_(2)O_(5)–(55-x)P_(2)O_(5)–xNb_(2)O_(5)(x=0–40,mol%).The dielectric parameters,including the dielectric strength and dielectric loss,are determined from the frequency and temperature-dependent complex permittivity data,revealing a significant dependence on the Nb2O5 content.The transition from a predominantly phosphate glass network(x<10,region I)to a mixed niobate–phosphate glass net-work(10≤x≤20,region II)leads to an increase in the dielectric parameters,which correlates with the observed trend in the direct-cur-rent(DC)conductivity.In the predominantly niobate network(x≥25,region III),the highly polarizable nature of Nb5+ions leads to a fur-ther increase in the dielectric permittivity and dielectric strength.This is particularly evident in Nb-40 glass-ceramic,which contains Na_(13)Nb_(35)O_(94) crystalline phase with a tungsten bronze structure and exhibits the highest dielectric permittivity of 61.81 and the lowest loss factor of 0.032 at 303 K and 10 kHz.The relaxation studies,analyzed through modulus formalism and complex impedance data,show that DC conductivity and relaxation processes are governed by the same mechanism,attributed to ionic conductivity.In contrast to glasses with a single peak in frequency dependence of imaginary part of electrical modulus,M″(ω),Nb-40 glass-ceramic exhibits two distinct contributions with similar relaxation times.The high-frequency peak indicates bulk ionic conductivity,while the additional low-fre-quency peak is associated with the grain boundary effect,confirmed by the electrical equivalent circuit(EEC)modelling.The scaling characteristics of permittivity and conductivity spectra,along with the electrical modulus,validate time-temperature superposition and demonstrate a strong correlation with composition and modification of the glass structure upon Nb_(2)O_(5) incorporation. 展开更多
关键词 phosphate glasses GLASS-CERAMICS impedance spectroscopy dielectric properties relaxation processes permittivity scaling conductivity scaling modulus formalism
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Boron nitride silicone rubber composite foam with low dielectric and high thermal conductivity
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作者 Shuilai Qiu Hang Wu +1 位作者 Fukai Chu Lei Song 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期224-230,共7页
Silicone rubber(SR)is widely used in the field of electronic packaging because of its low dielectric properties.In this work,the porosity of the SR was improved,and the dielectric constant of the SR foam was reduced b... Silicone rubber(SR)is widely used in the field of electronic packaging because of its low dielectric properties.In this work,the porosity of the SR was improved,and the dielectric constant of the SR foam was reduced by adding expanded microspheres(EM).Then,the thermal conductivity of the system was improved by combining the modified boron nitride(f-BN).The results showed that after the f-BN was added,the dielectric constant and dielectric loss were much lower than those of pure SR.Micron-sized modified boron nitride(f-mBN)improved the dielectric and thermal conductivity of the SR foam better than that of nano-sized modified boron nitride(f-nBN),but f-nBN improved the volume resistivity,tensile strength,and thermal stability of the SR better than f-mBN.When the mass ratio of f-mBN and fnBN is 2:1,the thermal conductivity of the SR foam reaches the maximum value of 0.808 W·m^(-1)·K^(-1),which is 6.5 times that before the addition.The heat release rate and fire growth index are the lowest,and the improvement in flame retardancy is mainly attributed to the high thermal stability and physical barrier of f-BN. 展开更多
关键词 Foam COMPOSITES dielectric properties Thermal conductivity Mechanical properties Flame retardant
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Influences of divalent ion substitution on the magnetic and dielectric properties of W-type barium ferrite
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作者 何诗悦 刘若水 +3 位作者 刘煦婕 叶先平 王利晨 沈保根 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期480-486,共7页
Saturation magnetization,magneto-crystalline anisotropy field,and dielectric properties are closely related to microwave devices applied at different frequencies.For regulating the magnetic and dielectric properties o... Saturation magnetization,magneto-crystalline anisotropy field,and dielectric properties are closely related to microwave devices applied at different frequencies.For regulating the magnetic and dielectric properties of W-type barium ferrites,single-phase BaMe_(2)Fe_(16)O_(27)(Me=Fe,Mn,Zn,Ni,Co) with different Me ions were synthesized by the high-temperature solid-state method.The saturation magnetization(Ms) range from 47.77 emu/g to 95.34 emu/g and the magnetic anisotropy field(H_a) range from 10700.60 Oe(1 Oe=79.5775 A·m^(-1)) to 13739.57 Oe,depending on the type of cation substitution in the hexagonal lattice.The dielectric permittivity and dielectric loss decrease with increasing frequency of the AC electric field in the low-frequency region,while they almost remain constant in the high-frequency region.The charac teristics of easy regulation and preparation make it a potential candidate for use in microwave device applications. 展开更多
关键词 W-type hexaferrite Raman spectra magnetic properties dielectric properties
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Silicon-based dielectric elastomer with amino-complexed hybrids towards high actuation performance
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作者 Zhengxing Dai Qingqing Liu +4 位作者 Xiaodong Qi Nan Zhang Ting Huang Jinghui Yang Yong Wang 《Nano Materials Science》 EI CAS CSCD 2024年第5期576-586,共11页
For improving the actuation performance at low electric fields of dielectric elastomers,achieving high dielectric constant(εr)and low modulus(Y)simultaneously has been targeted in the past decades,but there are few w... For improving the actuation performance at low electric fields of dielectric elastomers,achieving high dielectric constant(εr)and low modulus(Y)simultaneously has been targeted in the past decades,but there are few ways to accomplish both.In contrast to the classical strategies such as incorporating plasticizers or ceramic to prepare the silicon-based dielectric elastomers,here,blending an amino-complexed hybrid(polyethyleneimine(PEI)-Ag)with polydimethylsiloxane(PDMS)elastomer is reported as an alternative strategy to tailor theεr and Y.PEI-Ag not only exhibits excellent dielectric enhancement properties but also minimizes the PDMS crosslinking through amino-complexed reaction between PEI and Pt catalysts.The prepared dielectric elastomers have aεr of 7.2@10^(3)Hz and Y of 1.14 MPa,leading to an actuation strain of 22.27%at 35 V/μm.Hence,incorporating such novel hybrids based on dual amino-complexed effect on both matrix and particles sufficiently promotes the actuated performance of dielectric elastomers. 展开更多
关键词 Flexible composites dielectric property Electro-mechanical behaviour AGNPS
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