1000 resultados para ND ALLOY


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CH_3C_5H_4LnCl_2·2LiCl·nTHF与2mol的LiNPh_2在THF、已烷和甲苯混合液中反应,经DME萃取,得到[Li·(DME)_3][(η~5-CH_3C_5H_4)Ln(NPh_2)_3](Ln=La,Pr,Nd)。对其进行了元素分析、IR和NMR表征。镧配合物单晶结构测定表明,属单斜晶系,P2_1/a空间群,晶胞参数为α=1.7461(6)nm,b=1.6576(5)nm,c=1.8335(6)nm,β=96.04°,V=5.277um~3,Z=4,D_c=1.26g/cm_3,R=0.057,R_w=0.048。该配合物是一个离子对,La-N和La-C(环)键的平均距离分别为0.2459(8)和 0.2843(11)nm。稀土离子形成一个六配位的扭曲四面体。

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本文采用恒界面池法研究了诸因素对甲基磷酸二甲庚酯(P_(350))从硝酸体系中萃取Nd(Ⅲ)动力学的影响,求得反应的表观活化能为11.8kJ/mol,从实验结果推论出萃取过程为界面化学反应的控制机理,得出萃取反应速率方程,并提出中性磷氧萃取剂在萃取金属离子过程中可能存在阳离子交换反应机理。

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钙钛矿型含镓的稀土复合氧化物的发光及光谱性质已有研究和报道.进一步在稀土镓复合氧化物体系中掺进过渡元素Fe~(3+)离子,用XRD,XPS和IR方法研究了LaGa_(1-x)Fe_xO_3体系中磁性铁离子的自旋态及其对化合物结构,红外光谱等性质的影响.在此基础上,本文首次对LnGa_(1-x)Fe_xO_3(Ln=La,Pr,Nd)体系化合物的磁化率等磁性质进行初步探讨,以揭

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The reaction of LnCl3.2LiCl with 1 equiv of MeCpNa in THF gives the complexes [(THF)2Li(mu-Cl)2]2[MeCpLn(THF)] (Ln = Nd (1), La (2)) in good yield. These precursors react further with 2 equiv of LiNPh2 to produce the new complexes [Li(DME)3][MeCpLn(NPh2)3] (Ln = La (3), Pr (4), Nd (5)). They have been characterized by elemental analyses and IR and NMR spectra, as well as by structural analyses of 1 and 3. The chloride 1 crystallizes in the monoclinic space group P2(1)/n (No. 14) with a = 12.130 (5) angstrom, b = 17.343 (5) angstrom, c = 17.016 (5) angstrom, beta = 108.54 (3)-degrees, V = 3393.87 angstrom3, Z = 4, and D(c) = 1.45 g/cm3. Least-squares refinement led to a final R value of 0.051 (I greater-than-or-equal-to 3-sigma(I(o))) for 2004 independent reflections. Complex 3 crystallizes in the monoclinic space group P2(1)/c (No. 14) with a = 18.335 (6) angstrom, b = 16.576 (5) angstrom, c = 17.461 (6) angstrom, beta = 96.04 (3)-degrees, V = 5277.17 angstrom3, D(c) = 1.26 g/cm3, Z = 4, and R = 0.057 (I greater-than-or-equal-to 2.5-sigma(I(o))) for 3378 reflections. The structure of 3 consists of discrete ion pairs [Li(DME)3]+ and [MeCpLa(NPh2)3]- with average La-N and La-C(ring) distances of 2.459 (8) and 2.84 (1) angstrom, respectively.

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自1969年首次报道稀土环辛四烯基化合物Eu(C_8H_8)和Yb(C_8H_8)的合成以来,相继合成K[Ln(C_8H_8)_2],[Ln(C_8H_8)Cl·2THF]_2和[Ln(C_8H_8)·2THF]等,还报

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本文报道了三价钕与氮杂大环(简称L)配合物的合成和晶体结构.配合物组成为[Nd(L)-(CH_3CN)(CF_3SO_3)_3],晶体属于三斜晶系,空间群为PI,晶胞参数α=0.8738(2),b=1.2870(3),c=1.2900(3)nm;α=85.63(2),α=87.25(2),γ=78.30(2)°;最终偏差因子R=0.0370,R_w00385.配合物中钕为8配位,其配位多面体为扭曲的四方反棱柱体.

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近年来,对于稀土Ziegler-Natta催化剂活性体的研究比较活跃。使用催化剂活性体可以消除剩余烷基铝等因素对聚合反应的影响,比以前所用的多组分混合物的催化体系更客观地反映出聚合过程。我们在以前工作的基础上,从体系中分离出Nd-Al双金属活性体,并用于引发异戊二烯溶液聚合,探讨不同聚合条件下异戊二烯溶液聚合的规律,以利于对稀土催化聚合反应的深入了解。

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合成了三茚基稀土配合物(η~5-C_9H_7)_3Ln·OC_4H_8(Ln=Nd、Gd、Er),经元素分析、红外光谱、水解产物核磁共振谱及质谱表征,并测得了(η~5-C_9H_7)_3Nd·OC_4H_8(1)及(η~5-C_9H_7)_3Gd·OC_4H_8(2)的晶体结构。(1)、(2)均属六方晶系,P6_3空间群,Z=2。(1)的晶体学参数为a=b=1.1843(3)nm,c=1.0304(4)nm,V=1.25165(87)nm~3,D_c=1.49g·cm~(-3),最后一致性因子R=0.049;(2)的晶体学参数a=b=1.1805(2)nm,c=1.0236(2)nm,V=1.23536(56)nm~3,D_c=1.54 g·cm~(-3),R=0.023。平均Nd-C=0.2812nm,Gd-C=0.2795nm;Nd-O=0.2557(21)nm,Gd—O=0.2459(13)nm。配合物中四氢呋喃的四个碳原子处于完全无序状态。

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采用X射线四圆衍射仪测定了Nd(C_6H_5CH_2COO)_3·H_2O的晶体结构。配合物属于正交晶系,空间群为Pna2_1,晶胞参数为a=0.7983(1)nm,b=1.3975(1)nm,c=2.0282(2)nm,Z=4。采用TG—DTG—DTA和DSC研究了标题配合物的热分解机理和其过程的焓变。

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Ga-Nd合金对磁性材料及半导体材料的研制是非常有用的。本文详细地研究了采用低熔点的镓作为阴极,从KCl-NdCl_3熔盐中电解制备廉价Ga-Nd合金的工艺条件。 本研究采用KCl-NdCl_3熔盐体系进行电解。KCl为分析纯。NdCl_3由Nd_2O_3(>99.99%)加过量NH_4Cl混合后,在大瓷蒸发皿中于350℃进行搅拌反应,直至产物完全溶于水。用滴定法确定原料中NdCl_3的含量。以金属镓作阴极(纯度为99.99wt%),阴