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分散剂对磨制片状银粉性能的影响?
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作者 哈敏 董宁利 钟翔 《粉末冶金技术》 CAS CSCD 北大核心 2019年第1期36-39,45共5页
以热分解碳酸银得到的类球形银粉作为前驱体,使用硬脂酸、油酸、蓖麻油酸及正辛酸作为分散剂,采用机械球磨法制备片状银粉。通过扫描电镜(scanning electron microscope,SEM)、粒度分布统计(particle size distribution,PSD)、松装密度... 以热分解碳酸银得到的类球形银粉作为前驱体,使用硬脂酸、油酸、蓖麻油酸及正辛酸作为分散剂,采用机械球磨法制备片状银粉。通过扫描电镜(scanning electron microscope,SEM)、粒度分布统计(particle size distribution,PSD)、松装密度仪、振实密度仪、四探针仪等手段测试了片状银粉的显微形貌、粒度分布、松装密度、振实密度及导电性。结果表明,分散剂分子中碳链的长度影响片状银粉物理性能,使用油酸作为分散剂可以得到粒径分布窄、松装密度为1.0 g·cm-3、振实密度为1.7 g·cm-3的片状银粉,调制含质量分数50%Ag的低温固化银浆,其方阻小于10 mΩ·□-1。 展开更多
关键词 分散剂 片状银粉 机械球磨 导电性 物理性能
Peristaltic Flow of Shear Thinning Fluid via Temperature-Dependent Viscosity and Thermal Conductivity
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作者 S.Noreen A.Malik M.M.Rashidi 《理论物理通讯:英文版》 SCIE CAS CSCD 2019年第4期367-376,共10页
In this paper Williamson ?uid is taken into account to study its peristaltic ?ow with heat effects. The study is carried out in a wave frame of reference for symmetric channel. Analysis of heat transfer is accomplishe... In this paper Williamson ?uid is taken into account to study its peristaltic ?ow with heat effects. The study is carried out in a wave frame of reference for symmetric channel. Analysis of heat transfer is accomplished by accounting the effects of non-constant thermal conductivity and viscosity and viscous dissipation. Modeling of fundamental equations is followed by the construction of closed form solutions for pressure gradient, stream function and temperature while assuming Reynold’s number to be very low and wavelength to be very long. Double perturbation technique is employed, considering Weissenberg number and variable ?uid property parameter to be very small. The effects of emerging parameters on pumping, trapping, axial pressure gradient, heat transfer coe?cient, pressure rise,velocity pro?le and temperature are analyzed through the graphical representation. A direct relation is observed between temperature and thermal conductivity whereas the indirect proportionality with viscosity. The heat transfer coe?cient is lower for a ?uid with variable thermal conductivity and variable viscosity as compared to the ?uid with constant thermal conductivity and constant viscosity. 展开更多
关键词 TEMPERATURE-DEPENDENT VISCOSITY TEMPERATURE-DEPENDENT thermal CONDUCTIVITY shear thinning?uid PERISTALSIS
杭州淤泥质土的电渗电导率特性研究
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作者 罗战友 陶燕丽 +2 位作者 周建 邹宝平 祝行 《岩石力学与工程学报》 EI CAS CSCD 北大核心 2019年第A01期3222-3228,共7页
采用改进的MillerSoilBox试验装置,基于杭州淤泥质土,在3种不同含水量和含盐量下开展电渗试验,从总电导率和区域电导率2个方面分析土体电导率变化规律和分布特征,以揭示杭州淤泥质土的电渗电导率特性。结果表明:不同初始含水量下,土体... 采用改进的MillerSoilBox试验装置,基于杭州淤泥质土,在3种不同含水量和含盐量下开展电渗试验,从总电导率和区域电导率2个方面分析土体电导率变化规律和分布特征,以揭示杭州淤泥质土的电渗电导率特性。结果表明:不同初始含水量下,土体总电导率相近,均随通电时间逐渐减小,同时土体总电导率与实时含水量呈近似线性变化,线性变化率随初始含水量的增加而降低;不同初始含盐量下,土体总电导率呈现先上升后下降并最终趋于平缓的变化,电渗前期,总电导率峰值随初始含盐量的增大而增大,峰值出现时间随初始含盐量提高而推迟,电渗后期,不同初始含盐量下土体总电导率趋于相近;随着电渗的开展,土体电导率分布不均匀性先逐渐增大后有所缓解,最终阴极附近区域土体电导率与其他区域差异较大;不同含水量或含盐量下,土体电导率分布在电渗前期差异较大,后期趋于相近。研究成果可进一步揭示电渗机制,为电渗法设计计算方法的提出提供理论依据。 展开更多
关键词 土力学 杭州淤泥质土 电渗 电导率 含水量 含盐量
基于非制冷微测辐射热计的非晶硅锗薄膜电学特性研究 预览
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作者 陈哲权 何勇 +2 位作者 方中 潘绪超 何源 《激光与红外》 CAS CSCD 北大核心 2019年第3期336-340,共5页
采用等离子体增强化学气相沉积方法(PECVD)制备了应用于微测辐射热计的非晶硅锗薄膜(a-SixGey),并研究了不同反应气体流量比GeH4/SiH4对薄膜电学性能参数(电阻温度系数TCR和电导率)的影响。研究结果表明,随着流量比GeH4/SiH4的增大,薄... 采用等离子体增强化学气相沉积方法(PECVD)制备了应用于微测辐射热计的非晶硅锗薄膜(a-SixGey),并研究了不同反应气体流量比GeH4/SiH4对薄膜电学性能参数(电阻温度系数TCR和电导率)的影响。研究结果表明,随着流量比GeH4/SiH4的增大,薄膜电阻温度系数降低,电导率则呈现上升趋势。所制备的薄膜表现出了高TCR值(约3.5%/K^-1),适中的电导率(1.47×10^-3(Ω·cm)^-1)和优良的薄膜电阻均匀性(非均匀性<5%),在微测辐射热计热敏材料领域具有良好的应用前景。 展开更多
关键词 非晶硅锗薄膜 PECVD 电阻温度系数 电导率 微测辐射热计
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Effects of silicon addition on optical properties of mould flux with iron oxide and estimation of apparent thermal conductivity of flux
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作者 Rie Endo Yo Kan +2 位作者 Takashi Watanabe Miyuki Hayashi Masahiro Susa 《钢铁研究学报:英文版》 SCIE EI CAS CSCD 2019年第4期365-373,共9页
Mould flux with high absorptivity had been obtained in the reduction process of mould flux by silicon.For further utilisation of the mould flux with high absorptivity,the effect of silicon addition on the optical prop... Mould flux with high absorptivity had been obtained in the reduction process of mould flux by silicon.For further utilisation of the mould flux with high absorptivity,the effect of silicon addition on the optical property has been investigated.The synthesised mould flux powder with iron oxide was melted with the addition of silicon powder at 1703 K followed by quenching,thus forming a glassy sample.After 5-30-min reduction,the samples exhibited black opaque colour.Meanwhile,the samples that were reduced for 45-60 min had a bluish grey colour.Many iron-based particles dispersed in the samples were micrometre order in diameter.To determine the effect of iron particles on the optical properties of the sample,extinction,scattering and absorption efficiencies were calculated according to Mie theory.Result showed that both scattering on the iron particle and absorption by iron effectively increase the extinction efficiency in the mould flux.Moreover,the silicon particle in the flux has large scattering efficiency.The black opaque colour is contributed by the existence of silicon and iron particles.The apparent thermal conductivity was calculated for the solid flux.Results also indicated that the entire glassy mould flux would effectively work for mild cooling in a continuous casting process owing to high absorptivity and small thermal conductivity. 展开更多
关键词 MOULD FLUX Reduction Iron oxide Thermal CONDUCTIVITY OPTICAL property
Non-destructive microstructural analysis by electrical conductivity:Comparison with hardness measurements in different materials
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作者 Goncalo L.Sorger J.P.Oliveira +4 位作者 Patrick L.Inácio Norbert Enzinger Pedro Vilaca R.M.Miranda Telmo G.Santos 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第3期360-368,共9页
The use of non-destructive evaluation(NDE) techniques for assessing microstructural changes in processed materials is of particular importance as it can be used to assess, qualitatively, the integrity of any material/... The use of non-destructive evaluation(NDE) techniques for assessing microstructural changes in processed materials is of particular importance as it can be used to assess, qualitatively, the integrity of any material/structure. Among the several NDE techniques available, electrical conductivity measurements using eddy currents attract great attention owing to its simplicity and reliability. In this work, the electrical conductivity profiles of friction stir processed Ti6Al4 V, Cu, Pb, S355 steel and gas tungsten arc welded AISI 304 stainless steel were determined through eddy currents and four-point probe. In parallel, hardness measurements were also performed. The profiles matched well with the optical macrographs of the materials: while entering in the processed region a variation in both profiles was always observed. One particular advantage of electrical conductivity profiles over hardness was evident: it provides a better resolution of the microstructural alterations in the processed materials. Moreover, when thermomechanical processing induces microstructural changes that modify the magnetic properties of a material,eddy currents testing can be used to qualitatively determine the phase fraction in a given region of the material. A qualitative relation between electrical conductivity measurements and hardness is observed. 展开更多
关键词 NON-DESTRUCTIVE evaluation techniques Electrical CONDUCTIVITY HARDNESS FRICTION STIR processing Gas TUNGSTEN arc welding
Concise synthesis of NaTi2(PO4)3 nanocrystals with size and morphology control
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作者 Hanqing Dai Wenqian Xu +1 位作者 Kehan Yu Wei Wei 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第2期517-520,共4页
NaTi2 (PO4)3 (NTP) nanocrystals with high room-temperature ionic conductivity of 1.1×103 S/cm were prepared by a concise solvothermal method at 140 ℃ for 3 h, and the aspect ratios of all the NTP nanocrystals ar... NaTi2 (PO4)3 (NTP) nanocrystals with high room-temperature ionic conductivity of 1.1×103 S/cm were prepared by a concise solvothermal method at 140 ℃ for 3 h, and the aspect ratios of all the NTP nanocrystals are the closest to 0.7. It implies a moderate size-distribution of NTP nanocrystals obtained at 140 ℃ for 3 h is helpful for increasing packing density, and the packing density is the larger, so its conductivity is the higher. The controllability over size and morphology of the NTP nanocrystals via solvothermal temperature and time were investigated. The results suggest that our method is of great potential in synthesizing NTP nanocrystals with high room-temperature ionic conductivity at low cost. 展开更多
关键词 Nanocrystal Morphology ASPECT ratio Size-distribution IONIC CONDUCTIVITY
离子液体[emim]Ac密度和电导率的实验与理论研究 预览
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作者 何丽娟 陈帅帅 +2 位作者 李松波 刘素霞 田宝云 《应用化工》 CAS CSCD 北大核心 2019年第4期798-800,共3页
对离子液体[emim]Ac的密度和电导率进行了实验测定与理论模型关联。结果表明,离子液体[emim]Ac的密度随温度的升高逐渐减小,当温度范围为298.15~338.15 K时,[emim]Ac的密度值变化范围为1 072~ 1 024 kg/m 3;离子液体[emim]Ac的电导率随... 对离子液体[emim]Ac的密度和电导率进行了实验测定与理论模型关联。结果表明,离子液体[emim]Ac的密度随温度的升高逐渐减小,当温度范围为298.15~338.15 K时,[emim]Ac的密度值变化范围为1 072~ 1 024 kg/m 3;离子液体[emim]Ac的电导率随温度的升高逐渐增大,当温度范围为298.15~338.15 K时,[emim]Ac的电导率值变化范围为0.369~0.983 S/m;通过比较离子液体[emim]Ac密度及电导率的理论模型关联数据与实验测定数据,得出[emim]Ac密度及电导率的理论模型关联平均相对偏差和最大相对偏差分别为:0.82%, 2.65%和1.43%,2.91%,关联结果与实验测定结果一致,故认为所选模型可用于实验数据关联。 展开更多
关键词 [emim]Ac 密度 电导率 实验测定 模型关联
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气泡对换流阀内冷水电导率在线测量的影响 预览
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作者 马啸飞 《山西电力》 2019年第2期65-67,共3页
由于换流阀内冷水的电导率极低,内冷水电导率在线测量容易受到诸多因素的影响,气泡是常见的影响因素之一。分析了换流阀内冷水系统气泡的来源,阐明了气泡对换流阀内冷水电导率在线测量的影响,并提出了一些控制措施。
关键词 换流阀 内冷水 电导率 气泡
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Electrically Conductive and Flame Retardant Graphene/Brominated Polystyrene/Maleic Anhydride Grafted High Density Polyethylene Nanocomposites with Satisfactory Mechanical Properties
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作者 Yu Chen Jian Yao +2 位作者 Ming-Ke Xu Zhi-Guo Jiang Hao-Bin Zhang 《高分子科学:英文版》 SCIE CAS CSCD 2019年第5期509-517,共9页
Electrically conductive and flame-retardant maleic anhydride grafted high-density polyethylene(MA-HDPE) nanocomposites with satisfactory mechanical properties are fabricated by melt compounding MA-HDPE with polyethyle... Electrically conductive and flame-retardant maleic anhydride grafted high-density polyethylene(MA-HDPE) nanocomposites with satisfactory mechanical properties are fabricated by melt compounding MA-HDPE with polyethyleneimine(PEI)-modified reduced graphene oxide(PEI@RGO) as the conductive nanofiller and brominated polystyrene(BPS) as the flame retardant. The modification with PEI significantly improves the interfacial compatibility and dispersion of the RGO sheets in the MA-HDPE matrix, leading to electrically conductive nanocomposites with enhanced mechanical properties. Furthermore, the addition of 25 wt% of BPS makes the nanocomposite flame-retardant with a UL-94 V-0 rating. Thus, the multifunctional RGO/MA-HDPE nanocomposites with good electrical, flameretardant, and mechanical properties would have potential applications in construction and pipeline fields. 展开更多
关键词 Polymer NANOCOMPOSITES High density POLYETHYLENE GRAPHENE Electrical CONDUCTIVITY FLAME retardancy
海水电磁屏蔽体 预览
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作者 王身云 计想建 岑大维 《装备环境工程》 CAS 2019年第5期9-12,共4页
目的将海水作为一种电磁屏蔽材料,研究其电磁屏蔽效能以及影响因素。方法基于海水和玻璃的电磁特性参数,并利用电场和磁场切向分量连续边界条件,推导由双层玻璃封装海水所构成的复合电磁屏蔽体结构的屏蔽效能计算公式。结果具有一定厚... 目的将海水作为一种电磁屏蔽材料,研究其电磁屏蔽效能以及影响因素。方法基于海水和玻璃的电磁特性参数,并利用电场和磁场切向分量连续边界条件,推导由双层玻璃封装海水所构成的复合电磁屏蔽体结构的屏蔽效能计算公式。结果具有一定厚度和盐度的海水墙体可以展示出良好的电磁屏蔽效能。通过增加海水层的厚度,提高海水的盐度以及温度,均可以有效增强海水电磁屏蔽体的屏蔽效能。改变封装海水的玻璃层厚度,对海水电磁屏蔽体的屏蔽效能影响较小。结论海水可以作为一种有效的电磁屏蔽材料,并具有光波透明、电磁屏蔽效能易重构、可循环导热等独特的优势。在军事和民用领域,海水电磁屏蔽体将具有重要的理论和应用价值。 展开更多
关键词 海水 Debye模型 电导率 电磁屏蔽材料 屏蔽效能 传输系数
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快速测定盐碱土质含盐量的研究 预览
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作者 朱文霞 张欣艳 +2 位作者 钱飞隆 刘少国 张平 《黑龙江工业学院学报:综合版》 2019年第4期84-88,共5页
根据大庆盐碱土质的特点,在大庆高新区采集了30个土壤样品,利用残渣烘干-质量法测定了样品的全盐含量;测定了饱和土浆、土水比1∶1及1∶5土水混合液的电导率,并系统地研究了土壤全盐含量与不同土水比混合液电导率之间的关系。结果表明:... 根据大庆盐碱土质的特点,在大庆高新区采集了30个土壤样品,利用残渣烘干-质量法测定了样品的全盐含量;测定了饱和土浆、土水比1∶1及1∶5土水混合液的电导率,并系统地研究了土壤全盐含量与不同土水比混合液电导率之间的关系。结果表明:土壤全盐量与不同土水比混合液电导率之间都呈显著正相关关系,且土壤全盐含量与土水比1:1混合液电导率之间相关性最佳,应用二者间的相关方程,可根据混合液电导率快速确定土壤全盐量。 展开更多
关键词 盐渍土 含盐量 电导率 土水混合液
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Electrical conductivity of molten LiF–DyF3–Dy2O3–Cu2O system for Dy–Cu intermediate alloy production 预览
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作者 Shu-mei Chen Chun-fa Liao +3 位作者 Jue-yuan Lin Bo-qing Cai Xu Wang Yun-fen Jiao 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2019年第6期701-709,共9页
Dy–Cu intermediate alloys have shown substantial potential in the field of magnetostrictive and magnetic refrigerant materials.Therefore,this study focused on investigating the electrical conductivity of molten-salt ... Dy–Cu intermediate alloys have shown substantial potential in the field of magnetostrictive and magnetic refrigerant materials.Therefore,this study focused on investigating the electrical conductivity of molten-salt systems for the preparation of Dy–Cu alloys and on optimizing the corresponding operating parameters.The electrical conductivity of molten LiF–DyF3–Dy2O3–Cu2O systems was measured from 910 to 1030°C using the continuously varying cell constant method.The dependencies of the LiF–DyF3–Dy2O3–Cu2O system conductivity on the melt composition and temperature were examined herein.The optimal operating conditions for Dy–Cu alloy production were determined via analyses of the electrical conductivity and activation energies for conductance,which were calculated using the Arrhenius equation.The conductivity of the molten system regularly increases with increasing temperature and decreases with increasing concentration of Dy2O3 or Cu2O or both.The activation energy Eκof the LiF–DyF3–Dy2O3 and LiF–DyF3–Cu2O molten-salt systems increases with increasing Dy2O3 or Cu2O content.The regression functions of conductance as a function of temperature(t)and the addition of Dy2O3(W(Dy2O3))and Cu2O(W(Cu2O))can be expressed asκ=-2.08435+0.0068t-0.18929W(Dy2O3)-0.07918W(Cu2O).The optimal electrolysis conditions for preparing the Dy–Cu alloy in LiF–DyF3–Dy2O3–Cu2O molten salt are determined to be 2.0wt%≤W(Dy2O3)+W(Cu2O)≤3.0wt%and W(Dy2O3):W(Cu2O)=1:2 at 970 to 1000°C. 展开更多
关键词 electrical conductivity MOLTEN salt Dy–Cu alloy DYSPROSIUM OXIDE cuprous OXIDE
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导电二维配位聚合物框架材料在能源存储及转化领域的应用 预览
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作者 姜恺悦 杨重庆 庄小东 《功能高分子学报》 CAS CSCD 北大核心 2019年第2期155-177,共23页
配位聚合物框架材料具有高的比表面积、丰富的孔结构和金属配位中心,一直以来被视为能源领域的潜在电极材料。传统配位聚合物框架材料电导率低,因此,如何设计并合成具有一定导电性的配位聚合物框架材料,满足能源及其相关领域对于材料电... 配位聚合物框架材料具有高的比表面积、丰富的孔结构和金属配位中心,一直以来被视为能源领域的潜在电极材料。传统配位聚合物框架材料电导率低,因此,如何设计并合成具有一定导电性的配位聚合物框架材料,满足能源及其相关领域对于材料电学性质的要求,成为配位聚合物框架材料领域的研究热点方向之一。本综述介绍了近年来导电二维配位聚合物框架材料的设计思路及电导率测量方法,并对这类材料的制备及其在能源转化及存储方面的应用进行了总结。最后,对二维高导电配位聚合物今后的研究和发展方向进行了展望。 展开更多
关键词 二维 配位聚合物框架 导电性 合成 能源转化与存储
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聚苯胺包覆镍纤维的制备及电性能研究
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作者 杨莹 熊国宣 +1 位作者 姚伟林 黄海清 《化工新型材料》 CAS CSCD 北大核心 2019年第2期132-135,139共5页
镍纤维经预处理后,采用化学氧化法对其进行包覆改性,制备聚苯胺包覆改性镍纤维,以改善镍纤维的电性能。主要探究了掺杂剂种类、浓度、镍纤维长径比以及搅拌速率等因素对聚苯胺包覆镍纤维效果的影响,利用核磁共振、能谱仪和扫描电镜对产... 镍纤维经预处理后,采用化学氧化法对其进行包覆改性,制备聚苯胺包覆改性镍纤维,以改善镍纤维的电性能。主要探究了掺杂剂种类、浓度、镍纤维长径比以及搅拌速率等因素对聚苯胺包覆镍纤维效果的影响,利用核磁共振、能谱仪和扫描电镜对产物进行元素和形貌分析,采用四探针电阻率测试仪测试聚苯胺包覆镍纤维的电性能。结果表明:以0.1mol/L盐酸为掺杂剂,将长径比为8mm的镍纤维在0~5℃下以60r/min的转速聚合得到聚苯胺包覆镍纤维材料,其包覆层致密均匀,且得到最大的电导率,其值为2.62×10^3S/cm。 展开更多
关键词 镍纤维 聚苯胺 包覆 电导率
碳纳米管薄膜电热特性及其除冰性能 预览
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作者 秦文峰 游文涛 +2 位作者 钟勉 范宇航 韩孝强 《宇航材料工艺》 CAS CSCD 北大核心 2019年第1期86-90,共5页
采用碳纳米管薄膜(CNTF)作为电加热元件,研究碳纳米管薄膜对玻璃纤维增强树脂基复合材料结构表面的除冰性能,同时研究其电热性能。SEM14μm左右。XRD表明CNTF样品为微晶结构,结晶度差且含有少量杂质。空气环境通电,升温速率和最高恒定... 采用碳纳米管薄膜(CNTF)作为电加热元件,研究碳纳米管薄膜对玻璃纤维增强树脂基复合材料结构表面的除冰性能,同时研究其电热性能。SEM14μm左右。XRD表明CNTF样品为微晶结构,结晶度差且含有少量杂质。空气环境通电,升温速率和最高恒定温度随输入电压增大而迅速提高。输入电压为5 V温度95℃。在四次电热循环后,其表面电阻略有升高,均值从2.795Ω到3.870Ω。在9 V输入电压下,CNTF被迅速烧断,CNTF样品电流承载极限在1.8 A左右。利用其焦耳热性能进行除冰,质量为20 g冰块在树脂基玻璃纤维复合材料样品的表面脱落时间为240 s。表明CNTF在飞机除冰领域具有潜在应用价值。 展开更多
关键词 碳纳米薄膜 微观形貌 电导率 焦耳热 除冰
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Mapping Soil Electrical Conductivity Using Ordinary Kriging Combined with Back-propagation Network 预览
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作者 HUANG Yajie LI Zhen +4 位作者 YE Huichun ZHANG Shiwen ZHUO Zhiqing XING An HUANG Yuanfang 《中国地理科学:英文版》 SCIE CSCD 2019年第2期270-282,共13页
Accurate mapping of soil salinity and recognition of its influencing factors are essential for sustainable crop production and soil health. Although the influencing factors have been used to improve the mapping accura... Accurate mapping of soil salinity and recognition of its influencing factors are essential for sustainable crop production and soil health. Although the influencing factors have been used to improve the mapping accuracy of soil salinity, few studies have considered both aspects of spatial variation caused by the influencing factors and spatial autocorrelations for mapping. The objective of this study was to demonstrate that the ordinary kriging combined with back-propagation network(OK_BP), considering the two aspects of spatial variation, which can benefit the improvement of the mapping accuracy of soil salinity. To test the effectiveness of this approach, 70 sites were sampled at two depths(0–30 and 30–50 cm) in Ningxia Hui Autonomous Region, China. Ordinary kriging(OK), back-propagation network(BP) and regression kriging(RK) were used in comparison analysis;the root mean square error(RMSE), relative improvement(RI) and the decrease in estimation imprecision(DIP) were used to judge the mapping quality. Results showed that OK_BP avoided the both underestimation and overestimation of the higher and lower values of interpolation surfaces. OK_BP revealed more details of the spatial variation responding to influencing factors, and provided more flexibility for incorporating various correlated factors in the mapping. Moreover, OK_BP obtained better results with respect to the reference methods(i.e., OK, BP, and RK) in terms of the lowest RMSE, the highest RI and DIP. Thus, it is concluded that OK_BP is an effective method for mapping soil salinity with a high accuracy. 展开更多
关键词 ordinary KRIGING NEURAL network soil electrical CONDUCTIVITY VARIABILITY MAPPING Ningxia China
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银纳米线/聚乙烯醇导电复合材料的逾渗特性研究 预览
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作者 卢聘 曲兆明 +4 位作者 王庆国 何长安 赵世阳 成伟 王妍 《功能材料》 EI CAS CSCD 北大核心 2019年第3期3024-3027,3032共5页
采用多元醇法制备了长径比约为240的银纳米线(AgNWs),以聚乙烯醇(PVA)为基体、AgNWs为导电填料制备了导电复合材料;基于排斥体积理论和几何相变理论对银纳米线/聚乙烯醇导电复合材料的逾渗阈值进行了分析和预测。结果表明,基于排斥体积... 采用多元醇法制备了长径比约为240的银纳米线(AgNWs),以聚乙烯醇(PVA)为基体、AgNWs为导电填料制备了导电复合材料;基于排斥体积理论和几何相变理论对银纳米线/聚乙烯醇导电复合材料的逾渗阈值进行了分析和预测。结果表明,基于排斥体积理论计算得到的逾渗阈值(0.5816%)小于实际复合材料的实测数据;基于几何相变理论模型对材料逾渗阈值的拟合数据约为1.25%~1.31%,与实验测试得到的复合材料逾渗转变浓度范围一致性较好。因此,利用几何相变理论进行复合材料逾渗阈值和电导率的预测对于AgNWs/PVA导电复合材料的设计、制备及性能评价具有重要的指导作用。 展开更多
关键词 银纳米线/聚乙烯醇复合材料 排斥体积理论 几何相变理论 逾渗阈值 电导率
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Enhancing the thermoelectric performance of Bi2S3: A promising earth-abundant thermoelectric material
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作者 Ye Chen Dongyang Wang +5 位作者 Yuling Zhou Qiantao Pang Jianwei Shao Guangtao Wang Jinfeng Wang Li-Dong Zhao 《物理学前沿:英文版》 SCIE CSCD 2019年第1期111-122,共12页
Recently, bismuth sulfide (Bi2S3) has attracted much attention in the thermoelectric community owing to its abundance, low cost, and advanced properties. However, its poor electrical transport properties have prevente... Recently, bismuth sulfide (Bi2S3) has attracted much attention in the thermoelectric community owing to its abundance, low cost, and advanced properties. However, its poor electrical transport properties have prevented Bi2S3 devices from realizing high thermoelectric performance. In this work, our motivation is to decrease the large electrical resistivity, which is recognized as the origin of the low ZT value in undoped Bi2S3. We combined melting and spark plasma sintering (SPS) in a continuous fabrication process to produce Bi2S3–xSex (x = 0, 0.09, 0.15, 0.21) and Bi2S2.85–ySe0.15Cly (y = 0.0015, 0.0045, 0.0075, 0.015, 0.03) samples. Our results show that Se alloying at S sites can narrow the band gap and activate intrinsic electron conduction, leading to a high power factor of ~2.0 μW·cm–1·K–2 at room temperature in Bi2S2.85S0.15, about 100 times higher than that of undoped Bi2S3. Moreover, our further introduction of Cl atoms into the S sites resulted in a second-stage optimization of carrier concentration and simultaneously reduced the lattice thermal conductivity, which contributed to a high ZT value of ~0.6 at 723 K for Bi2S2.835Se0.15Cl0.015. Our results indicate that high thermoelectric performance could be realized in Bi2S3 with earth-abundant and low-cost elements. 展开更多
关键词 THERMOELECTRIC BI2S3 CARRIER concentration LATTICE thermal CONDUCTIVITY
ITO/Ag/AgNW新型复合透明导电薄膜性能研究
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作者 张晓东 魏葳 +3 位作者 杨钊 陈微微 黄林泉 田占元 《半导体光电》 CAS 北大核心 2019年第2期231-233,238共4页
采用磁控溅射和湿法涂布技术制备了一种ITO/Ag/AgNW结构的新型复合透明导电薄膜。研究其光学、电学等性能发现:ITO/Ag/AgNW薄膜在400~700nm的平均透过率高于ITO/Ag/ITO薄膜,且方块电阻远小于ITO/Ag/ITO薄膜,达到6.9Ω/□;耐弯折性能测试... 采用磁控溅射和湿法涂布技术制备了一种ITO/Ag/AgNW结构的新型复合透明导电薄膜。研究其光学、电学等性能发现:ITO/Ag/AgNW薄膜在400~700nm的平均透过率高于ITO/Ag/ITO薄膜,且方块电阻远小于ITO/Ag/ITO薄膜,达到6.9Ω/□;耐弯折性能测试后,其方块电阻约增加62%,达11.2Ω/□。研究结果表明,这种新型的复合透明导电薄膜具有低阻、高透及耐弯折良好的特性,在柔性显示领域具有一定的应用潜力。 展开更多
关键词 透明导电膜 ITO/Ag/AgNW 导电性 柔韧性
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