期刊文献+
共找到8篇文章
< 1 >
每页显示 20 50 100
La_(x)Sr_(1-x)MnO_(3)微波吸收特性的研究 被引量:7
1
作者 胡国光 尹萍 吕庆荣 《磁性材料及器件》 CAS CSCD 2000年第6期14-17,47,共5页
对 Lax Sr1 -x Mn O3 微波吸收特性进行了研究 ,在 8~ 1 2 GHz频率范围 ,x取值不同 ,吸收特性不同 ,在 x取 0 .4,涂层厚度为 2 .2 1 mm时 ,最高吸收峰为 2 5d B。测试分析认为 ,损耗吸收来自磁损耗和介电损耗 ,吸收峰与介电损耗角正切... 对 Lax Sr1 -x Mn O3 微波吸收特性进行了研究 ,在 8~ 1 2 GHz频率范围 ,x取值不同 ,吸收特性不同 ,在 x取 0 .4,涂层厚度为 2 .2 1 mm时 ,最高吸收峰为 2 5d B。测试分析认为 ,损耗吸收来自磁损耗和介电损耗 ,吸收峰与介电损耗角正切最大值相对应 ,在 1 0 .5GHz附近。初步比较了掺杂碳纤维、W型和 Y型平面六角铁氧体后 ,样品吸收特性的变化。 展开更多
关键词 la_(x)sr_(1-x)MnO_(3) 微波吸收特性 磁损耗和介电损耗
下载PDF
La_(1-x)Sr_(x)TiO_(3)薄膜的高通量X射线衍射
2
作者 张一烽 王洋洲 +2 位作者 吴广 陈飞 冯振杰 《上海大学学报(自然科学版)》 CAS CSCD 北大核心 2022年第3期552-557,共6页
高通量材料合成方法和高通量材料表征手段区别于传统低效率的“试错法”材料发展方法,极大地加速了材料科学的变革和发展.通过设计程序进行了高通量X射线衍射实验,在保证数据分辨率条件下,高效地表征了La_(1-x)Sr_(x)TiO_(3)薄膜上多个... 高通量材料合成方法和高通量材料表征手段区别于传统低效率的“试错法”材料发展方法,极大地加速了材料科学的变革和发展.通过设计程序进行了高通量X射线衍射实验,在保证数据分辨率条件下,高效地表征了La_(1-x)Sr_(x)TiO_(3)薄膜上多个数据位点的晶体结构,验证了其成分的连续变化性质,为后续开展更多类型的高通量X射线衍射实验提供了指导. 展开更多
关键词 高通量x射线衍射 钛酸锶 la_(1-x)sr_(x)tio_(3)薄膜
下载PDF
Co掺杂La_(0.7)Sr_(0.3)MnO_(3)的制备及其电化学性能的研究
3
作者 甄海妮 吕静波 《科学技术创新》 2024年第16期66-69,共4页
采用溶胶-凝胶法制备了Co掺杂的La_(0.7)Sr_(0.3)Mn_(1-x)Co_(x)O_(3)钙钛矿氧化物(LSMC),利用X射线衍射(XRD)、扫描电子显微镜(SEM)对样品的微观形貌结构进行表征,并通过循环伏安、电化学阻抗谱和恒流充放电测试详细研究了Co掺杂对电... 采用溶胶-凝胶法制备了Co掺杂的La_(0.7)Sr_(0.3)Mn_(1-x)Co_(x)O_(3)钙钛矿氧化物(LSMC),利用X射线衍射(XRD)、扫描电子显微镜(SEM)对样品的微观形貌结构进行表征,并通过循环伏安、电化学阻抗谱和恒流充放电测试详细研究了Co掺杂对电化学性能的影响。研究表明,随着Co掺杂浓度的增加,LSMC电极材料的比容量呈现先增大后减小的趋势,其中LSMC55表现出最高的比容量。在1 mol L^(-1)的Na_(2)SO_(4)电解液中,扫描速率为2 mV s^(-1)时,LSMC55电极的比容量为150 F g^(-1)。结果表明,对La_(0.7)Sr_(0.3)MnO_(3)(LSM)的B位进行Co掺杂,可以改善LSM的电化学性能。 展开更多
关键词 超级电容器 钙钛矿氧化物 la_(0.7)sr_(0.3)Mn_(1-x)Co_(x)O_(3) 掺杂 电化学性能
下载PDF
溶胶-凝胶法制备La_(1-x)Sr_(x)MnO_(3)及其电磁性能研究 被引量:1
4
作者 王伟超 刘顾 +4 位作者 汪刘应 葛超群 王龙 许可俊 陈孟州 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2022年第3期1003-1010,共8页
采用溶胶-凝胶法制备了La_(1-x)Sr_(x)MnO_(3)(LSMO)(x=0,0.1,0.2,0.3)纳米微粉。探究了 Sr^(2+)的掺杂量对LSMO晶体结构、磁学性质、电磁特性和微波吸收性能的影响。结果表明,随 Sr^(2+)含量的升高,样品的晶格常数和Mn-O-Mn键角增大,... 采用溶胶-凝胶法制备了La_(1-x)Sr_(x)MnO_(3)(LSMO)(x=0,0.1,0.2,0.3)纳米微粉。探究了 Sr^(2+)的掺杂量对LSMO晶体结构、磁学性质、电磁特性和微波吸收性能的影响。结果表明,随 Sr^(2+)含量的升高,样品的晶格常数和Mn-O-Mn键角增大,平均晶粒尺寸逐渐下降,样品出现从反铁磁性向铁磁性的转变,复介电常数呈先增大后减小的趋势。在有效的波频段为2~18 GHz内,x=0的样品在厚度为2 mm时有最佳吸波效果,反射率损耗小于–10 dB对应的有效吸波频段为12.5~18 GHz,有效带宽达到5.5 GHz;Sr^(2+)的掺杂可使吸波频段有效向低频移动,在X波段内,x=0.2的样品在厚度为2.3 mm时的有效带宽达2.6 GHz,证明LSMO是一种性能优异的介电损耗型吸波材料。 展开更多
关键词 钙钛矿 la_(1-x)sr_(x)MnO_(3) 电磁性能 吸波性能 溶胶-凝胶法
原文传递
Composition dependence of giant electrocaloric effect in PbxSr1-xTiO_(3) ceramics for energy-related applications 被引量:4
5
作者 Peng-Zu Ge Xiao-Dong Jian +6 位作者 Xiong-Wei Lin Xin-Gui Tang Zhi Zhu Qiu-Xiang Liu Yan-Ping Jiang Tian-Fu Zhang Sheng-Guo Lu 《Journal of Materiomics》 SCIE EI 2019年第1期118-126,共9页
Pb_(x)Sr_(1-x)TiO_(3)(x=0.30,0.35,0.40,0.45,0.50 and 0.55)ceramics were fabricated by a solid-state reaction route.Xeray diffraction data at room temperature show PST samples shift from cubic to tetragonal phase with ... Pb_(x)Sr_(1-x)TiO_(3)(x=0.30,0.35,0.40,0.45,0.50 and 0.55)ceramics were fabricated by a solid-state reaction route.Xeray diffraction data at room temperature show PST samples shift from cubic to tetragonal phase with the increase of Pb^(2+) content.The microstructures were observed by scanning electron microscopy.Dielectric measurement was employed to investigate the ferroelectriceparaelectric phase transition behavior.Temperature dependent polarizationeelectric field hysteresis loops were conducted to study the electrocaloric effect(ECE)of the ferroelectric ceramics by indirect methods over a wide temperature range.Direct measurement of temperature change(DT)at room temperature for all samples can achieve 0.79e1.86 K.What's more,a giant ECE(△T=2.05 K,EC strength(△T/△E)=0.51×10^(-6) K m/V,under 40 kV/cm)was obtained in the sample of x=0.35 near phase transition temperature.Our results suggest that the ceramics are promising cooling materials with excellent EC properties for energy related applications. 展开更多
关键词 Pb_(x)sr_(1-x)tio_(3)ceramics Electrocaloric effect Phase transition Energy applications
原文传递
面向宽温域功能器件的连续组分外延铁电薄膜
6
作者 熊沛雨 倪壮 +7 位作者 林泽丰 柏欣博 刘天想 张翔宇 袁洁 王旭 石兢 金魁 《物理学报》 SCIE EI CAS CSCD 北大核心 2023年第9期178-186,共9页
Ba_(x)Sr_(1–x)TiO_(3)(BST)铁电薄膜因为拥有高介电常数、强电场调谐性和较低的微波频段介电损耗可应用于微波可调谐器件.然而铁电材料中普遍存在的介电常数-温度依赖性使得常规单组分铁电薄膜的高可调率温区受制于相变温度,难以满足... Ba_(x)Sr_(1–x)TiO_(3)(BST)铁电薄膜因为拥有高介电常数、强电场调谐性和较低的微波频段介电损耗可应用于微波可调谐器件.然而铁电材料中普遍存在的介电常数-温度依赖性使得常规单组分铁电薄膜的高可调率温区受制于相变温度,难以满足宽温域适用性的需求.为研究可用于宽温域功能器件的铁电薄膜,采用脉冲激光沉积(PLD)技术制备了单组分Ba_(0.5)Sr_(0.5)TiO_(3)薄膜、Ba_(0.2)Sr_(0.8)TiO_(3)薄膜以及Ba_(0.2)Sr_(0.8)TiO_(3)/Ba_(0.5)Sr_(0.5)TiO_(3)异质结构薄膜.通过对比其介电性能,发现垂直方向上Ba/Sr组分分布可有效改善BST薄膜的温度依赖性,然而异质结构的构建可能带来界面问题,同时也使其品质因子难以提升.本文提出采用独特的水平方向连续组分薄膜制备技术制备BST组合薄膜,有望在拓宽BST薄膜相变温区的同时避免界面控制的难题. 展开更多
关键词 Ba_(x)sr_(1–x)tio_(3)薄膜 可调谐微波器件 连续组分薄膜 温度依赖性
下载PDF
Effect of Sr-substitution on the structural and dielectric properties of LaFeO_(3) perovskite materials
7
作者 D.Triyono C.A.Kafa H.Laysandra 《Journal of Advanced Dielectrics》 CAS 2018年第5期47-56,共10页
The study aims to investigate the structural and dielectric properties of perovskite La_(1-x)Sr_(x)FeO_(3)(x=0.1,0.2,0.3,and 0.4)synthesized by solgel and sintering methods.X-ray diffraction(XRD),transmission electron... The study aims to investigate the structural and dielectric properties of perovskite La_(1-x)Sr_(x)FeO_(3)(x=0.1,0.2,0.3,and 0.4)synthesized by solgel and sintering methods.X-ray diffraction(XRD),transmission electron microscopy(TEM),and LCR-Meter were used to identify the phase,crystallography parameters,morphology,particle size,and electrical behavior of the synthesized perovskite materials.The samples showed a single-phase orthorhombic crystal structure with Pbnm space group.Sr-substitution induced the volume unit cell and crystallite size to decrease.The synthesized nanoparticles were uniform and homogeneous with the particle size less than 200 nm.Impedance spectroscopy(IS)was used to explain the electrical behavior as a function of frequency(100 Hz to 1 MHz)at various temperatures(300–373 K).The presence of small polarons as charge carriers within the grain and grain boundary were elucidated from the electrical conductivity experiments.Sr-substitution caused the dielectric constant and electronic conductivity to increase with the highest values obtained from La_(1-x)Sr_(x)FeO_(3)(x=0.4). 展开更多
关键词 la_(1-x)sr_(x)FeO_(3) impedance spectroscopy CONDUCTIVITY DIELECTRIC
原文传递
The effect of Ba/Sr ratio on the Curie temperature for ferroelectric barium strontium titanate ceramics 被引量:2
8
作者 Hamed A.Gatea Iqbal S.Naji 《Journal of Advanced Dielectrics》 CAS 2020年第5期32-42,共11页
The powders of lead-free material namely(nonhazardous)barium strontium titanate(BST)with different stoichiometric compo-sitions have been synthesized by the sol-gel method.Ba_(1−x)Sr_(x)TiO_(3)(BST)materials possess t... The powders of lead-free material namely(nonhazardous)barium strontium titanate(BST)with different stoichiometric compo-sitions have been synthesized by the sol-gel method.Ba_(1−x)Sr_(x)TiO_(3)(BST)materials possess the properties of both ferroelectric and dielectric materials.These materials have spontaneous polarization that can be reversed by an applied electric field and they remain polarized even when the applied external electric field is removed.Synthesized samples have been subjected to structural,morphological,and dielectric characterizations.In this study,BST nanopowders with different substitutions of x(where x=0.2,0.3,0.4,0.5,and 0.6)were prepared by the sol-gel method,which is an easy method with low power consumption and low tem-perature requirement and produces higher yield.Nanopowders had average particle sizes of 12-24 nm and particles sizes after sintering at 1000°C for 3 h were 197,267,79.80,63.09,and 63 nm.All resulting pellets had a polycrystalline structure.Crystal structure,space group,morphological characterization,and particle size were determined from the structural analysis using X-ray powder diffraction(XRD),energy-dispersive X-ray spectroscopy(EDX),and scanning electron microscopy(SEM).The dielec-tric measurements were made for BST pellets under different frequencies(1-200 kHz)from room temperature to 250℃.The dielectric constants for the bulk were 743,1566,1091,766,and 626 for x=0.2,0.3,0.4,0.5,and 0.6,respectively.From dielectric measurements,samples with x=0.2 and 0.3 had the Curie temperatures of 70℃ and 28.5℃,respectively,and remained intact below 0℃.The sample with x=0.3 had a good dielectric measurement and moderate dissipation factor;it may be used in capac-itance application as energy stores. 展开更多
关键词 Curie Temperature dielectric constant sol gel Ba_(1-x)sr_(x)tio_(3) perovskite structure
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部