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101.
R. F. Klevtsova L. A. Glinskaya T. E. Kokina S. V. Larionov 《Journal of Structural Chemistry》2003,44(2):256-267
Single crystals of [Ni(Phen)(iBu2PS2)2] (I) and [Ni(Phen)3](iBu2PS2)2 (III) compounds were grown, and their structures were determined by Xray diffraction analysis (CAD4 diffractometer, MoK
radiation, 3336 F
hkl
, R = 0.0373 for I and 2575 F
hkl
for III). The crystals of complex I have a triclinic unit cell with the following parameters: a = 11.097(1) , b = 14.903(2) , c = 22.650(3); = 75.18(1)°, = 80.50(1)°, = 75.07(1)°, V = 3479.2(7)3, Z = 4, calc = 1.255 g/cm3, and space group
1; the crystals of III have a monoclinic unit cell with the following parameters: a = 19.010(3), b = 15.481(1) , c = 17.940(3); = 97.58(1)°, V = 5233.5(12)3, Z = 4, calc = 1.292 g/cm3, and space group C2/c. The structure of complex I is built from mononuclear molecules, and the structure of III, from [Ni(Phen)3]2+ complex cations and i Bu2PS2
- outersphere anions. The NiN2S4 coordination polyhedra in the structure of I and NiN6 in the structure of III are distorted octahedra. Based on structural data, the interaction between the coordinated Phen molecules of complexes I, [Ni(Phen)2(iBu2PS2)](iBu2PS2) (II), and III is considered, as well as the packing modes of these complexes. 相似文献
102.
103.
Porous anodic alumina (PAA) was used as a template to prepare Co nanowires array from 1-ethyl-3-methylimidazolium chloride ionic liquid by direct current method. The surface morphology of porous anodic alumina template was observed by field emission-scanning tunneling microscopy (FE-SEM) before and after the electrodeposition of Co nanowires. The electrodeposition of Co nanowires was characterized by transmission electron microscopy (TEM) and X-ray powder diffraction (XRD). TEM results indicate that the Co nanowire surface is coarse and porous when aqueous solution was used as electrolyte, and the Co nanowire deposited from the ionic liquid is uniform and smooth. XRD results show that the electrodeposition of Co is a mixture of crystal and microcrystal phase. 相似文献
104.
105.
利用分子束技术改变甲烷的平动能E_k来研究E_k及其法向分量E_n对甲烷在Ni表面及La薄膜上激活解离吸附的影响。对CH_4/Ni及CH_4/La系统, 当甲烷的平动能E_k分别低于58.5 kJ·mol~(-1)及52.3 kJ·mol~(-1)时, 没观察到甲烷的解离吸附。当甲烷的平动能超过此阈值时, 即对CH_4/Ni系统, 当Ek=58.5增至63.8 kJ·mol~(-1)时, 初始沾着几率s_0由0至0.54线性增加; 对CH_4/La系统, 当E_k=52.3增至63.8 kJ·mol~(-1)时, S_0由0至0.49线性增加。这些结果表明, 两个系统的化学吸附是不经过前趋态的直接化学吸附。最后求出CH_4/Ni, CH_4/La系统的表观活化能分别为46.8 kJ·mol~(-1)和38.1 kJ·mol~(-1)。 相似文献
106.
本文以二茂镍为母体化合物,以氧化铝和氧化硅为担体制备了担载镍催化剂。为了表征其结构特点,对这些催化剂热分解处理前后的样品在日本筑波高能物理研究所(Photon-Factory)的同步辐射加速器BL—10B EXAFS实验站进行了外延x-光精细结构谱测定(透射法)。以单散射球面波理论对实验结果进行了多参数拟合,同时对母体化合物也进行了平行测定和拟合,以验证数据及拟合方法的可靠性。研究结果表明,母体化合物的EXAFS结果与文献XRD相一致;母体化合物与担体表面发生了强烈的化学作用;镍组分在催化剂表面高度分散,氧化铝与Ni(C_5H_5)_2有更强的相互作用形成。Ni[(O)_s]_n(n≈4),近一半的镍原子周围有0.30 nm处的镍原子散射;氧化硅上除Ni[(CO)_s]_n(n≈3)外,在0.30 nm处有配位数为2的非成键Ni原子。 相似文献
107.
Anna Rakowska Robert Filipek Krzysztof Sikorski Marek Danielewski Renata Bachorczyk 《Mikrochimica acta》2004,145(1-4):183-186
The interdiffusion process in thin and thick (500nm–60µm) Au–Ni layers deposited on different substrates is studied using the EDS technique. In-depth X-ray analysis based on the Pouchou and Pichoir method is applied for obtaining the concentration profiles in nanometre scale multi-layers. A theoretical analysis using the Darken method is employed for modelling interdiffusion in the Au–Ni system. Computer simulations, where intrinsic diffusivities of the Au and Ni are functions of composition, are presented and compared with experimental results. 相似文献
108.
Yu. N. Belokon' 《Russian Chemical Bulletin》1992,41(5):868-884
The complexes of glycine, -alanine, and -alanine with (S)-[N-(N-benzylprolyl)amino] benzophenone formed by Ni(II) and Cu(II) ions and Schiff bases enter into different nucleophilic and electrophilic reactions with the formation of diastereoisomeric complexes which decompose into proteinogenic and nonproteinogenic L-amino acids with a high chemical yield and elevated optical purity (70–90%). Optically pure amino acids can be obtained from diastereoisomerically pure complexes after the complexes are separated by recrystallization of the mixture of diastereoisomeric complexes formed. A new type of interphase catalysts of C-alkylation of achiral Schiff bases was proposed. The catalysts are positively charged Ni(II) and Cu(II) complexes of Schiff bases of chiral diamines. In some cases, these complexes have a higher activity and capacity to execute asymmetric alkylation than traditional chiral interphase catalysts based on cinchonidine.Based on materials in the section report by Yu. N. Belokon' to the 7th European Symposium on Organic Chemistry, ESOC-7.A. N. Nesmeyanov Institute of Organoelemental Compounds, Russian Academy of Sciences, 117813 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 5, pp. 1106–1127, May, 1992. 相似文献
109.
110.
Ni/SiO2催化剂上甲烷催化裂解制氢 总被引:9,自引:5,他引:9
研究了固定床反应器上甲烷在Ni/SiO2催化剂上的裂解反应,并分别用O2、H2O进行催化剂失活/活化循环实验,并对催化剂用XRD进行分析。结果表明,Ni/SiO2催化剂具有良好的催化性能,甲烷转化率~40%,并能在150 min的时间内保持其活性,无论是用空气氧化还是水蒸气汽化,都能有效地活化已失活的催化剂。XRD实验显示,多次裂解-再生循环过程,对催化剂结构没有明显破坏。 相似文献