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Formation of Nanoscale Intermetallic Phases in Ni Surface Layer at High Intensity Implantation of Al Ions

I.A.Bozhko , S.V.Fortuna , I.A.Kurzina , I.B.Stepanov , E.V.Kozlov , Yu.P.Sharkeev

材料科学技术(英)

The results of experimental study of nanoscale intermetallic formation in surface layer of a metal target at ion implantation are presented. To increase the thickness of the ion implanted surface layer the high intensive ion implantation is used. Compared with the ordinary ion implantation, the high intensive ion implantation allows a much thicker modified surface layer. Pure polycrystalline nickel was chosen as a target. Nickel samples were irradiated with Al ions on the vacuum-arc ion beam and plasma flow source "Raduga-5". It was shown that at the high intensity ion implantation the fine dispersed particles of Ni3Al, NiAl intermetallic compounds and solid solution Al in Ni are formed in the nickel surface layer of 200 nm and thicker. The formation of phases takes place in complete correspondence with the Ni-Al phase diagram.

关键词: High intensive ion implantation , null , null

(I-3)-丁基罗丹明B缔合微粒体系的光谱特性

梁爱惠 , 蒋治良 , 李振中 , 康彩艳

应用化学 doi:10.3969/j.issn.1000-0518.2004.12.003

采用共振散射光谱、荧光光谱、吸收光谱、扫描电子显微镜测试技术,研究了(I-3)-丁基罗丹明B(BRhB)-0.08 mol/L HCl体系. 结果表明,BRhB在585 nm有1个吸收峰,在580 nm处有1个荧光峰,在570 nm处有1个同步荧光峰. 当BRhB与I-3存在时,二者形成粒径约60 nm的缔合纳米微粒,在420、530和605 nm处产生3个共振散射(RS)峰;而在580 nm处荧光峰猝灭、585 nm处吸收峰降低. 碘(I)浓度在2.0×10-7~40×10-7 mol/L范围内与共振散射光强度成线性关系. 光谱和扫描电镜研究结果表明,BRhB-(I-3)缔合纳米微粒和界面的形成是导致体系荧光猝灭、吸收峰降低和RS增强的根本原因.

关键词: I2 , 丁基罗丹明B , 缔合纳米微粒 , 荧光猝灭 , 共振散射 , 痕量分析

Zero-field splitting and local lattice distortions for Fe3+ ions in some I-b-IIIb-VI2 semiconductors

Zeitschrift Fur Naturforschung Section a-a Journal of Physical Sciences

The EPR zero-field splitting D for Fe3+ ions in some I-b-IIIb-VI2 semiconductors is calculated with the superposition model. The calculated D values, when using the local rotation angles i(Fe3+) for Fe3+ in CuGaS2 and AgGaS2 crystals, are consistent with the observed values, whereas for Fe3+ in CuAIS(2) crystal they are not. The calculated results are discussed. The local lattice distortions except the local rotation angles tau for Fe3+ in CuAlS2 are suggested.

关键词: Electron Paramagnetic Resonance;local lattice distortion;superposition;model;Fe3+;CuMS2(M = Al, Ga, In);AgGaS2;crystal;cuals2;esr

稀土区奇奇核πh11/2(×)νi13/2带B(M1)/B(E2)比值增强特性

陆景彬 , 刘运祚 , 孙亮 , 杨东 , 梁国栋 , 王守宇 , 马英君 , 赵广义 , 李险峰 , 崔兴柱 , 李明非 , 霍俊德 , 曾国模 , 竺礼华 , 吴晓光

原子核物理评论 doi:10.3969/j.issn.1007-4627.2005.02.003

在稀土区奇奇核πh11/2(×)νi13/2转动带中, 系统地观测到随转动频率或角动量增加, B(M1)/B(E2)曲线表现出所谓parabola-like形状, 即在增加到某一转动频率或自旋后, B(M1)/B(E2)比值快速增强. 基于推转模型和粒子转子模型关于奇奇核二准粒子转动带磁偶极约化跃迁几率的描述, 对稀土区双奇核的这一行为进行了讨论. 指出该现象的发生与νi13/2准中子转动顺排特性密切相关. B(M1)/B(E2)比值在接近第二带交叉(即BC准中子对顺排)的较高频率处的增强效果, 可以理解为主要来源于带交叉引起的波函数中混合四准粒子成分的结果. 通过对B(M1)/B(E2)比值的增强效果发生在较低频率处的分析, 对稀土区奇奇核πh11/2(×)νi13/2带角动量耦合图像有了进一步认识.

关键词: 高自旋态 , 奇奇核 , 电磁跃迁特性 , 顺排

PHASE DIAGRAM OF Nd-Fe-B TERNARY SYSTEM——I.Isothermal Section at Room Temperature

ZHANG Ning , Centrall Iron and Steel Research Institute , Ministry of Metallurgical Industry , Beijing. ChinaLUO Yang , San Huan New Material Research and Development Center , Academia Sinica , Beijing , China

金属学报(英文版)

The microstructures of both as-cast and homogenized Nd-Fe-B ternary alloys have been studied. The stable phase regions existing in Nd-Fe-B ternary system at room temperature have been established by the microzone composition analysis and the phase identification. Based on the obtained results, an isothermal section of Nd-Fe-B ternary system at room temperature was drawn.

关键词: phase diagram , null , null

Phase evolution and magnetic metals co-substituted studies of La and refractory co-substituted alpha i-Fe/R2Fe14B-type nanocomposites

W.C.Changt , S.H.Wang , S.J.Chang , M.Y.Tsai , Q.Chen

材料科学技术(英)

Phase evolution and magnetic properties of (Nd0.95La0.05)(9.5 similar to 11)Febal.M2B10.5, where M=Cr, Ti, Mb, V, Mo, Zr, Hf, Ta, Mn or W, melt spun ribbons have been investigated. Almost all the alloy ribbons, except for (Nd0.95La0.05)(9.5)Fe78M2B10.5 (M=Mo and Mn), consist merely two magnetic phases, namely alpha-Fe and R2Fe14B, which display a better combination of H-i(c) and magnetic energy product. Remanence (B-r) and coercivity (H-i(c)) values in the range of 8.0 to 9.1 kG and 9.5 to 18.9 kOe, respectively, can be achieved. Among compositions studied, the Ti and W-substitutions were found to be most effective in increasing the Br and H-i(c), respectively. For a fixed refractory metal substitution, namely, M=Cr, Ti or Mb, an increase in the total rare earth concentration resulted in nanocomposites of small grain sizes and a high volume fraction of the R2Fe14B phase, leading to an increase in the magnetic properties.

关键词:

磁场退火对纳米晶Fe74.5Cu1Nb2Si17.5B5合金饱和磁致伸缩系数和μi-T曲线的影响研究

史瑞民 , 王治 , 郑燕 , 卢建敏

功能材料 doi:10.3969/j.issn.1001-9731.2017.04.026

研究了不同退火温度下形成的纳米晶Fe74.5Cu1Nb2Si17.5B5合金经过磁场退火后,其饱和磁致伸缩系数λs、矫顽力Hc和μi-T曲线的变化.研究表明,经过磁场退火后,纳米晶合金的矫顽力出现不同程度的降低,温度在350℃以下时,初始磁导率表现出明显的提高,这些性能的改善归因于合金饱和磁致伸缩的减小.

关键词: 纳米晶合金 , 磁场退火 , 磁致伸缩 , 矫顽力 , μi-T曲线

高Br纳米晶Fe73Cu1Nb2V1.5Si13.5B9合金的铁损行为(I)低频损耗行为

张延忠 , 金慧娟 , 施英

功能材料与器件学报 doi:10.3969/j.issn.1007-4252.2002.03.005

在f=10-3×103Hz和Bm=0.1-1.0T范围内,研究了高Br纳米晶Fe73Cu1Nb2V1.5Si13.5B9合金的每周总损耗和频率的关系.P/f对f的行为明显地呈现非线性.大约在200Hz以下的范围内,非线性特征特别明显.用损耗统计理论中的"磁体"的行为能相当好地描述这种非线性行为.在较低的频段内,活动的磁体数n和动态过剩场Hexc是线性相关的,而在较宽和较高频段内,n与Hexc的关系是非线性的.

关键词: 纳米晶合金 , 铁损 , 过剩损耗

气相色谱微波诱导等离子体原子发射光谱检测器对C,P,Si,Sn,BI元素的响应特性的研究

师宇华 , 郑健 , 杨任飞 , 于爱民

色谱 doi:10.3321/j.issn:1000-8713.2003.06.023

以微波诱导等离子体作为气相色谱的原子发射光谱检测器,在优化实验参数的基础上,考察了该检测器对有机化合物中的C,P,Si,Sn,BI元素的响应特性(检出限、线性范围和精密度).结果表明:该检测器在仪器成本、功率消耗和气体消耗等方面明显优于气相色谱-电感耦合等离子体-原子发射光谱检测器(GC-ICP-AED).对各元素测定的检出限优于GC-ICP-AED约1个数量级,尤其适合于BI元素的测定.通过对不同种类有机化合物中碳元素相对响应值的测定,初步探讨了该等离子体光源对有机化合物的碎片原子化程度及其规律以及相应的响应机理.结果表明:以氩气为工作气体的surfatron器件作为等离子体光源时,有机化合物中碳元素的响应与化合物的结构有一定的关系.

关键词: 气相色谱 , 微波诱导等离子体 , 原子发射光谱 , 相对响应值

Preparation of I_2 Clusters and Their Absorption Spectra

Zhaojun LIN , Zhanguo WANG , Wei CHEN and Lanying LIN(Lab. of Sendconductor Materials Science , Institute of Semiconductors , Chinese Academy of Sciences , Beijing 100083 , China)

材料科学技术(英)

Samples have been prepared at different temperatures by loading I2 molecules into the cages of zeolite 5A, and the measurements of the absorption spectra have been carried out for the prepared samples. It is shown that I2 molecular clusters are formed in the cages of zeolite 5A,and it is also found that moIecuIar clusters which are bonded with intermoIecuIar forces have an important feature, namely, the intermolecular distance in molecular clusters can be changed on different preparing conditions and the blue shift of absorption edges can not be as the criterion of forming molecular clusters.

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