Methane Combustion Over Fe, Co and Ni Modified Manganese Oxide Catalysts

Fe-Mn, Co-Mn and Ni-Mn composite oxide catalysts based on high specific surface area MnO₂ precursor were prepared and applied to catalytic combustion of CH₄. Results were compared with that of unmodified MnOx and 1wt.% Pd/-Al₂O₃. Below 450°C, manganese oxide catalysts show higher activity than Pd/-Al₂O₃, while the modified manganese oxide catalysts exhibit higher activity than the unmodified one below 420°C. All catalysts were characterized by means of N₂-BET, XRD, TG-DTA and H₂-TPR. Due to the interaction between Fe, Co or Ni oxides and manganese oxide, the activity of the oxygen species of the modified catalysts is improved, which leads to the increase of their CH₄ combustion activity.     

Study of silica supported PtxNi1-x catalysts by ion scattering spectroscopy

As supported Pt_xNi_1–x catalysts are used for hydrogenation reactions, it seemed necessary to assess the surface composition of the reduced samples. To approach the usual reduction conditions we applied in situ reduction in a reaction chamber (1 mbar H₂ up to 500 °C) placed in ultra high vacuum recipient (UHV: 10^–9 to 2.10^–10mbar). All ion scattering spectroscopy measurements were performed in UHV. Charging of the samples was avoided by electron bombardment (5 eV). The variation of the surface composition was determined after subsequent sputtering, thermal treatment at 500 °C and during oxygen adsorption. A comparison with previous results of surface compositions of binary alloys (polycrystalline foils [1, 2] and single crystals Pt_xNi_1–x [3]) is given.Dedicated to Professor Dr. rer. nat. Dr. h. c. Hubertus Nickel on the occasion of his 65th birthday     

原子吸收光谱法测定拉伸断口铬镍钼钛钢样品中主成分

研究了毫克级铬镍钼风样品中主成分镍的火焰原子吸收光谱法（FAAS法）和铬、钼、钒、钛、铝的塞曼恒温平台石墨炉原子吸收光谱法（ZSTPF－AAS法）。采用了微波溶样技术作为防污染样品预处理技术，采用石墨管硅涂层改进技术提高了仪器的测试精度。其中铬、镍、钼、钒、钛、铝的相对标准偏差分别为2.7%,0.97%,8.6%,7.3%,1.7%,7.3%。其加标回收率分别为96.5%,97%,96.7%,93%,98%,91%。通过分析，发现在较低温度下铬镍钼钛钢断面上有轻微的钼偏析现象，可能是拉伸断裂的主要化学影响因素。     

载镍沸石上NH3-TPD脱附峰的非酸性探讨

NH_3-TPD技术表征固体催化剂的酸性似乎已很成熟,其实不然。如该技术表征HZSM-5沸石时,有作者观察到773K左右的高温脱氨峰,而有些作者则检测不到。诚然,各作者间所用试样及预处理条件等存在差异,但实验装置和实验操作条件不同带来的影响也不可忽视。此外,该技术在用于表征一些新的较复杂的催化剂时,其程脱谱也会呈现出新现象,这些现象有时是不能通过酸性来解释的,这是因为NH_3作为探针分子不仅具有碱性,同时还有还原性和配位性。本文对载镍沸石上NH_3-TPD谱图中出现的某些新峰进行了剖析和归属。     

STRUCTRE AND PROPERTIES OF COMPOSITE Ni/HARD CARBON FILMS PREPARED BY PLASMA DEPOSITION

IntroductionHardcarbonfilmsprcparcdb}'vari0usplasmaprocesscsareofc0nsidcrablcinterestbccauscofthcirunusualmcchanical-opticalandelcctricalpropertiesll~3l.Rccently,ithasReceive(IJl111c5,l9`)5;,.`,1iis()tI1ie)\tioII,1'ceil'edJtl1)'l4,l995*'I11isprojectiss[1pportcdh}tl1cNatiol1a1Nat[lntlScicl1ccI`()ul1dati()l1ofCl1il1aal1dtl1eI,aboraton'ofSolidI,ubricati()l1,l.al1/l10ulnstitutcofCl1cn1icalPh\'sics,111cChincscAcadcl11\'ofScicnccs.benfoundthattheinc0rporati0nofmetaIintocarbonfilmscangrcatl}'…     

Geometrical characteristics of four-coordinate complexes of Ni,Pd, and Pt containing triphenylphosphine as ligand

A statistical analysis based on crystal structure results of 4-coordinated complexes of Ni, Pd, and Pt containing triphenylphosphine as ligand has been performed using the Cambridge Structural Data Base. Distorted square-planar coordination appears as the most probable one presented by these metals.

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Geometrische Charakteristika von vier-koordinierten Komplexen des Ni, Pd und Pt mit Triphenylphosphin als Ligand

Zusammenfassung Es wurde unter Verwendung der Cambridge Strukturdatenbank eine statistische Analyse von Resultaten an vier-koordinierten Komplexen des Ni, Pd und Pt mit Triphenylphosphin-Ligand durchgeführt. Dabei ergab sich eine verzerrte quadratisch-planare Koordination als die am meisten wahrscheinliche Geometrie.

     

Two Polymorphs of (Anilinium)(18-Crown-6)[Ni(dmit)2]: Structure and Magnetic Properties

Two polymorphs of monovalent [Ni(dmit)₂]⁻ (dmit²⁻=2-thioxo-1,3-dithiole-4,5-dithiolate) crystals A and B, (anilinium)(18-crown-6)[Ni(dmit)₂], were prepared, and the structure and magnetic properties were investigated. In these crystals, the [Ni(dmit)₂]⁻ molecules form dimers, which arranged into chains between the supramolecular cation structure (anilinium)(18-crown-6). In crystal A, supramolecular cation formed a regular stack, inducing ladder structure of [Ni(dmit)₂], whose magnetism had been well fitted by spin ladder equation with the spin gap of Δ=190 K. Crystal B is ca. 3% more densely packed compared to crystal A. Due to the dense packing, supramolecular cation stack is distorted, which prevented the intermolecular interaction between [Ni(dmit)₂]⁻ dimers in direction corresponds to the ladder-leg direction in crystal A. Reflecting the [Ni(dmit)₂]⁻ arrangement, crystal B showed a temperature dependence of magnetic susceptibility well reproduced by the singlet-triplet thermal activation model, whose antiferromagnetic exchange interaction (2J) was 140 K.     

3-(水杨酰肼)-丁基-2-酮肟和两个镍的酮肟配合物的合成和晶体结构

合成了3-(水杨酰肼)-丁基-2-酮肟H₂L(1，C₁₁H₁₃N₃O₃)和2个镍的3-(水杨酰肼)-丁基-2-酮肟化合物[Ni(HL)(CH₃COO^-)(C₅H₅N)₂](2)和[Ni(HL)₂]·2C₃H₇NO（3）。化合物1晶体属单斜晶系，空间群为P2₁/n，晶体学参数为：a=0.451 87(2) nm，b=2.086 8(1) nm，c=1.224 48(9) nm，β=94.974(3)°，V=1.150 3(1) nm³，Z=4，D_c=1.358 g·cm^-3，μ=0.101 mm^-1，F(000)=496，R=0.0435，wR=0.142 5。化合物2晶体属单斜晶系，空间群为P2₁/n，晶体学参数为：a=1.362 39(8) nm，b=1.345 37(6) nm，c=1.438 54(7) nm，β=113.138(3)°，V=2.424 6(2) nm³，Z=4，D_c=1.398 g·cm^-3，μ=0.843mm^-1，F(000)=1 064，R=0.042 4，wR=0.116 6。化合物3晶体属单斜晶系，空间群为P2₁/c，晶体学参数为：a=1.104 22(7) nm，b=2.860 1(1) nm，c=1.114 13(7)nm，β=114.589(5)°，V=3.199 5(3) nm³，Z=4，D_c=1.398 g·cm^-3，μ=0.667 mm^-1，F(000)=1 416，R=0.057 6，wR=0.1535。在化合物1晶体中，酮肟分子之间通过分子间氢键形成二维网状结构。在化合物2中，每个镍(Ⅱ)离子由1个3-(水杨酰肼)-丁基-2-酮肟的2个氮原子和1个氧原子，2个吡啶分子中的2个氮原子和1个乙酸根中的1个氧原子形成畸变的NiN₄O₂八面体配位构型，存在分子内氢键O-H(肟)…O(乙酸根)和O-H(酚)…N(酰肼)。在化合物3晶体中，每个镍(Ⅱ)离子由2个3-(水杨酰肼)-丁基-2-酮肟的4个氮原子和2个氧原子配位，形成畸变的NiN₄O₂八面体配位构型。晶体中存在O-H…O和O-H…N两种分子内氢键和O-H…O分子间氢键。     

混合溶剂火焰原子吸收法直接测定原油中的镍

混合溶剂火焰原子吸收法直接测定原油中的镍刘广东袁存光张丙华刘文钦（石油大学（华东），山东东营２５７０６２）彭力（中国石油天然气总公司环保处，北京１００７２４）关键词原油，混合溶剂，无机盐标准，原子吸收法，镍测定原油中，微量元素镍、钒、铁、铜的存在对...     

Novel Isatin-Schiff Base Cu (II) and Ni(II) Complexes. X-ray Crystal Structure of Bis[3-(4-hexylphenylimino)-1H-indol-2(3H)-one]-dichlorocopper(II) Complex

Schiff bases of isatin were reported to possess antibacterial, antifungal, antiviral, anti-HIV, antiprotozoal, and anthelmintic activities1. They also exhibit significantanticonvulsant activity, apart from other pharmacological properties2. Conductingsubs…