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聚乙二醇-四氧化三铁纳米粒子复合材料的结构、物理性质及应用(英文) 被引量:3
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作者 夏娟 宋乐新 +1 位作者 党政 邵志成 《物理化学学报》 SCIE CAS CSCD 北大核心 2013年第7期1524-1533,共10页
在β-环糊精作保护剂条件下,制备了高对称的十八面体四氧化三铁(Fe3O4)纳米材料.通过胶体化学方法,合成了一系列不同起始计量比的聚乙二醇(PEG)和Fe3O4纳米粒子复合物(CM-1-CM-4).这些PEG复合材料展示出重要特性:首先,它们的表面形貌依... 在β-环糊精作保护剂条件下,制备了高对称的十八面体四氧化三铁(Fe3O4)纳米材料.通过胶体化学方法,合成了一系列不同起始计量比的聚乙二醇(PEG)和Fe3O4纳米粒子复合物(CM-1-CM-4).这些PEG复合材料展示出重要特性:首先,它们的表面形貌依赖于Fe3O4的计量;其次,PEG的熔化过程受Fe3O4的影响,并且直接与Fe3O4的含量相关;进一步研究表明,除CM-4外,Fe3O4的引入导致PEG结晶度下降,而且Fe3O4纳米粒子量越少,降低幅度越大;更为有趣的是,PEG的降解过程受制于Fe3O4纳米粒子的影响,导致不同降解产物的出现;而且,与纯Fe3O4纳米粒子一样,复合材料中的Fe3O4也显示典型的软铁磁性行为,但饱和磁化强度相对较小;此外,X射线光电子能谱(XPS)实验揭示在这些PEG复合材料中,有从Fe到O的电子转移,Fe电子密度的降低可用来解释复合材料饱和磁化强度的减小;最后,这些PEG复合材料呈现出对有机染料的表面增强拉曼效应,并且这种效应随Fe3O4纳米粒子含量的增加而增加.这些结果将会对聚合物/无机纳米粒子复合材料的发展起到推进作用. 展开更多
关键词 纳米粒子 聚乙二醇 四氧化三铁 微波吸收 软铁磁性 复合物
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Properties of magneto-rheological fluids based on amorphous micro-particles 被引量:1
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作者 董旭峰 马宁 +3 位作者 齐民 李金海 关新春 欧进萍 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第12期2979-2983,共5页
To improve the magneto-rheological (MR) properties of magneto-rheological fluids, self-made amorphous alloy particles, the composition of which was Fe76Cr2Mo2Sn2P10B2C2Si4, were used as the disperse phase to replace t... To improve the magneto-rheological (MR) properties of magneto-rheological fluids, self-made amorphous alloy particles, the composition of which was Fe76Cr2Mo2Sn2P10B2C2Si4, were used as the disperse phase to replace traditional carbonyl iron (CI) particles to prepare amorphous based magneto-rheological fluid (AMRF). Soft magnetic properties and densities of the amorphous particles and the CI particles were tested and compared. The results indicate the amorphous particles present a lower density but larger magnetization intensity and larger permeability at lower field levels. Properties of the AMRF with 20% particles in volume fraction were tested and compared with the CI based MR fluid (CMRF). The AMRF presents a saturation yield stress of 41 kPa at ~227 kA/m and a sedimentation ratio of 80%. The results indicate the magneto-rheological fluid based on amorphous micro-particles has better MR properties and sedimentation stability than that based on CI particles at lower field levels (0-200 kA/m). 展开更多
关键词 magneto-rheological fluids amorphous particles carbonyl iron soft magnetic properties MICROSTRUCTURE
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聚(2,4-噻唑)的合成及其稀土螯合物的磁性能研究 被引量:3
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作者 唐建斌 孙维林 +1 位作者 江黎明 沈之荃 《化学通报》 CAS CSCD 北大核心 2004年第1期30-32,共3页
合成了一种新型的共轭高分子 (PTz) ,并制备了它与稀土离子 Nd3 +的螯合物 (PTz-Nd3 + ) ,利用红外、核磁、元素分析及 X射线能谱仪对它们的结构进行了表征。 PTz- Nd3 + 的磁性研究表明 。
关键词 聚(2 4-噻唑) 合成 稀土螯合物 磁性 结构表征 软铁磁性
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Co含量对磁性非晶合金Fe85-xCoxTi7Hf6B2电学特性的影响 被引量:2
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作者 陈澄 黄琳 +3 位作者 Kim Sumin 朴红光 Haein Choi-Yim Kim Dong-Hyun 《稀有金属》 EI CAS CSCD 北大核心 2019年第7期693-698,共6页
研究了由单铜辊真空熔融纺丝技术制备的扁平带状铁基磁性非晶态合金Fe(85-x)CoxTi7Hf6B2(x=20, 30, 35,原子分数)的电学特性。这种软铁磁性非晶合金与其他含FeCo类合金一样,当Co含量达到30%附近时其饱和磁化强度会呈现最大值。尽管如此... 研究了由单铜辊真空熔融纺丝技术制备的扁平带状铁基磁性非晶态合金Fe(85-x)CoxTi7Hf6B2(x=20, 30, 35,原子分数)的电学特性。这种软铁磁性非晶合金与其他含FeCo类合金一样,当Co含量达到30%附近时其饱和磁化强度会呈现最大值。尽管如此,体系中Co含量的改变并没有对这种铁基非晶合金的磁性能产生较大的影响。值得注意的是,在这种铁基非晶合金体系中Co含量的改变可导致其电学特性发生显著的转变。比如:当Co含量为20%时,其电阻温度系数为负值,表现出类似于半导体的电阻温度特性和P型半导体的电学特性;然而,当Co含量增加到30%和35%时,其电阻温度系数则转变为正值,呈现出类似一般金属导体的电阻温度特性。不仅如此,根据该非晶合金中各组成元素的电负性和电离势揭示了Co含量可调控载流子(空穴)浓度的物理机制,为新型铁基非晶合金材料的设计提供新方法。 展开更多
关键词 非晶态合金 软铁磁性 磁性半导体 电阻温度系数
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水溶性La_(0.88)Sr_(0.12)MnO_3纳米粒子的非水相合成 被引量:3
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作者 程文正 苏玮 +5 位作者 刘晓 李雪梅 方宁 王现红 吴君华 刘红玲 《河南大学学报(自然科学版)》 CAS 2015年第2期143-146,共4页
采用纳米微乳液法,以三嵌段共聚物聚氧乙烯-聚氧丙烯-聚氧乙烯(PEO-PPO-PEO)为表面活性剂,乙酰丙酮镧(III),乙酰丙酮锰(III)和乙酰丙酮锶(II)为前驱体,1,2-十六烷二醇为还原剂成功合成了水溶性La0.88Sr0.12MnO3纳米粒子.FT-IR分析证实... 采用纳米微乳液法,以三嵌段共聚物聚氧乙烯-聚氧丙烯-聚氧乙烯(PEO-PPO-PEO)为表面活性剂,乙酰丙酮镧(III),乙酰丙酮锰(III)和乙酰丙酮锶(II)为前驱体,1,2-十六烷二醇为还原剂成功合成了水溶性La0.88Sr0.12MnO3纳米粒子.FT-IR分析证实该纳米粒子表面存在PEO-PPO-PEO分子,XRD和TEM分析表明该纳米粒子基本上呈球形、粒径分布窄、结晶度高,VSM测试表明该纳米粒子室温下显示软铁磁性.纳米粒子在水中快速和高效的分散收集过程,表明该纳米粒子具有良好的水溶性和磁操控性. 展开更多
关键词 La0.88Sr0.12MnO3纳米粒子 纳米微乳液法 软铁磁性 水溶性
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Microwave magnetic properties of soft magnetic thin films 被引量:2
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作者 CHAI GuoZhi GUO DangWei +1 位作者 FAN XiaoLong XUE DeSheng 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第7期1200-1207,共8页
We review our works that focus on the microwave magnetic properties of metallic, ferrite and granular thin films. Soft magnetic material with large permeability and low energy loss in the GHz range is a challenge for ... We review our works that focus on the microwave magnetic properties of metallic, ferrite and granular thin films. Soft magnetic material with large permeability and low energy loss in the GHz range is a challenge for the inforcom technologies. GHz magnetic properties of the soft magnetic thin films with in-plane anisotropy were investigated. It is found that several hundreds of permeability at the GHz frequency was achieved for Col00_xZrx and Co90Nbl0 metallic thin films because of their high satu- ration magnetization, and an adjustable resonance frequency from 1.3 to 4.9 GHz was obtained. Compared with the metallic thin films, the weaker saturation magnetization of Ni-Zn ferrite thin films results in several tens of permeability at the GHz frequency, but the larger resistivity of the ferrite prepared in situ without any heating treatments has lower energy loss. In order to obtain materials with large permeability and low energy loss in the GHz range, the [CoFe-NiZn ferrite] composite granular thin films were investigated, where the advantage of higher saturation magnetization for the metallic alloy and the high resis- tivity as well as high saturation magnetization for the ferrite results in a good GHz magnetic performance. 展开更多
关键词 microwave magnetic properties metallic thin films ferrite thin films granular thin films in-plane uniaxial anisotropy
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FePCCu nanocrystalline alloys with excellent soft magnetic properties
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作者 JIN YunLong FAN XingDu +2 位作者 MEN He LIU XinCai SHEN BaoLong 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第12期3419-3424,共6页
The effect of Cu addition on crystallization behavior and soft magnetic properties of Fe84-xP10C6Cux (x = 0-1.15) alloys was investigated. Low-cost FePCCu nanocrystalline alloys dispersed with ct-Fe phase with an av... The effect of Cu addition on crystallization behavior and soft magnetic properties of Fe84-xP10C6Cux (x = 0-1.15) alloys was investigated. Low-cost FePCCu nanocrystalline alloys dispersed with ct-Fe phase with an average grain size of 15-35 nm were obtained by appropriately annealing the melt-spun ribbons at 683 K for 5 min. The Fe83.25P10C6Cu0.75 nanocrystalline alloy ex- hibits a high Bs of 1.65 T, low Hc of 3.3 A/m and high μc at 1 kHz of 21 100, which is superior to the traditional FePC soft magnetic alloys. The core loss is as low as 0.32 W/kg at 1.0 T and 50 Hz, which is 60% that of nonoriented Fe 6.5 mass% Si-steel. It is encouraging to synthesize this Fe-based nanocrystalline alloy with excellent soft-magnetic properties even using commercially industry-grade raw materials, which is promising for the future industrial applications. 展开更多
关键词 soft magnetic ahoy Fe-based nanocrystalline alloy soft magnetic properties low core loss
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Development of soft magnetic amorphous alloys with distinctly high Fe content 被引量:1
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作者 PingBo Chen AnDing Wang +5 位作者 ChengLiang Zhao AiNa He Gang Wang ChunTao Chang XinMin Wang Chain-Tsuan Liu 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2017年第10期45-50,共6页
This paper reports on the preparation of Fe82.7-85.7Si2-4.9B9.2-11.2P1.5.2.7C0,8 soft magnetic amorphous alloys with a distinctly high Fe content of 93.5-95.5 wt.% by component design and composition adjustment. All a... This paper reports on the preparation of Fe82.7-85.7Si2-4.9B9.2-11.2P1.5.2.7C0,8 soft magnetic amorphous alloys with a distinctly high Fe content of 93.5-95.5 wt.% by component design and composition adjustment. All alloys can be readily fabricated into completely amorphous ribbon samples with good surface quality by the single copper roller melt-spinning method. These alloys show good bending ductility and excellent magnetic properties after annealing, i.e., low coercivity (He) of 3.3-5.9 A/m, high permeability (μe) of 5000-10000 and high flux saturation density (Bs) of 1.63-1.66 T. The mechanism of the good glass forming ability (GFA)and soft-magnetic properties are explored. The amorphous alloys with the high Fe content comparable to that of the desired high Si alloy can be promising candidates for the potential application in electric devices. 展开更多
关键词 metallic glasses alloy design ANNEALING magnetic properties shear band
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