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1.
八十年代以来,由于发现铝、镓、铟的金属有机化合物在制备半导体材料、特种陶瓷和电致发光材料等方面具有重要的应用价值 [1],因此,对此类化合物的研究报道也逐渐增多。 IIIA族金属有机配合物由于成键结构复杂,可以调节的结构点多,具有丰富的化学内含,而又具有相对稳定的化学性质 [2],所以,通过对 IIIA族金属有机配合物的研究,可以寻找到更稳定的、性能更佳的 MO(Metal Organic)新源,对于 MOCVD(Metal Organic Compound Vapor Deposit)技术的发展有着重要的意义 [3]。氨基亚甲基酚或萘酚由于其作为染料 [4]、杀虫剂 [5]、…  相似文献   

2.
含镓、锡的铝合金在碱性溶液中的活化机理   总被引:6,自引:0,他引:6  
镓锡合金沉积于铝阳极表面 ,形成活化点 ,是铝阳极活化的根本原因 .简单的Al_Sn、Al_Ga二元合金在碱性介质中不能活化 .Al_Sn_Ga多元合金阳极溶解时 ,Ga、Sn溶解进入溶液 .锡离子首先还原沉积于铝阳极表面 ,镓离子又在沉积的锡上沉积 ,在铝合金阳极表面不断形成Ga_Sn合金活性点 .低溶点的合金由于其良好的流动性 ,以单个或多个原子的形式嵌入氧化膜 ,形成活性点 ,起到了局部分离氧化膜的作用 ,是铝合金阳极活化的关键  相似文献   

3.
提出了气相色谱法测定食品塑料包装材料中三甲基氯化锡含量的方法。样品经乙酸乙酯萃取,采用J&W DB-17毛细管色谱柱(30 m×0.25 mm,0.25μm)分离,用电子捕获检测器测定。三甲基氯化锡的质量浓度在0.334~26.76 mg·L-1范围内与其峰面积呈线性关系,检出限(3s)为0.000 6 mg·L-1。方法的回收率在77.6%~83.3%之间,测定结果的相对标准偏差(n=6)在2.5%~4.6%之间。  相似文献   

4.
The reactions of dibutylamine (DBA) with aluminum tribromide and gallium trichloride (MX3) in a benzene solution were studied using calorimetric and dielectrometric titration. The formation of stable and highly polar molecular complexes DBA · M2X6, DBA · MX3, 2DBA · MX3, and 6DBA · MX3 was established.  相似文献   

5.
6.
试样溶于适当的混合酸中,蒸至恰干,用pH 3.0的苯二甲酸氢钾缓冲溶液溶解残渣.用硫代乙酰胺和三氯化钛共沉淀从试样溶液将锡(Ⅳ)及铅(Ⅱ)分离,所得沉淀溶于浓盐酸中制成盐酸(1 9)的试液,并分部分此溶液分别进行锡及铅的氢化物发生-原子荧光光谱法测定.对方法的精密度和回收率做了试验,测得锡的相对标准偏差(n=6)在0.74%~0.96%之间,回收率在98.1%~100.9%之间;测得铅的相对标准偏差(n=6)在0.64%~1.41%,回收率在97.6%~100.6%之间.  相似文献   

7.
A series of fluorozirconate glasses in ZrF4-SnF2-GaF3 and ZrF4-SnF2-BaF2 systems have been studied by vibrational spectroscopy. The glass net contains not only fluorozirconate polyhedra, but also fluorostannate and fluorogallate groups. When contained in amounts of more than 10 mol.% in a glass, tin difluoride is a glass-forming agent. Gallium trifluoride in the same amount or higher forms GaF6 polyhedra.  相似文献   

8.
The sorption isotherms of water and tetrachloromethane vapors are studied, and the porous structures of aluminum tin phosphate gels coprecipitated at various Al/Sn molar ratios are analyzed. The resultant samples contain both micro- and mesopores. The structure of aluminum tin phosphate is suggested to contain slitlike pores that do not change during drying because of the presence of polyaquahydroxoaluminum cations introduced via an exchange with interlayer cations of tin(IV) hydrophosphate.  相似文献   

9.
Al/Co alloys with different element ratios were studied by X-ray diffraction analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The surface propagation of components of the Ga/In eutectic was studied in situ by energy-dispersive spectroscopy in the microscope chamber, and their propagation rate was estimated. It decreases with increasing Co content. Interaction of the Al/Co alloy with the liquid Ga/In eutectic was compared to that of the previously studied Al/Ni and Al/Fe alloys.  相似文献   

10.
The kinetics of the contact deposition of tin on aluminum from alkaline stannite solutions is studied by atomic absorption spectroscopy, gravimetry, titrimetry, X-ray diffractometry, and polarization diagrams. In the initial stage of the process, when regularities of non-steady-state diffusion are fulfilled, a large potential jump is observed. Therefore, to evaluate the rate of the contact exchange, it is suggested to use a correction factor equal to the ratio of the actual cathodic current density to the current density calculated from the polarization curve. On disperse aluminum, the rate is higher than that on compact aluminum because of different conditions for the diffusion of ions of tin(II) to the aluminum surface.  相似文献   

11.
含镓、锡的铝合金在碱性溶液中的阳极行为   总被引:4,自引:0,他引:4  
铝的电极电位负,为一1.66V(VS.SHE),电化当量高(298Ah/g)是一种理想的阳板材料.但是由于铝在空气和水中表面形成一层致密的氧化膜,使其在中性溶液中处于钝化状态.而在酸性或碱性溶液中铝表面氧化膜就会被溶解破坏,与水直接反应,腐蚀中途难以中止.这一直是影响铝作为阳板材料应用和深入研究的障碍,特别是对铝阳极活化溶解机理的研究进展缓慢.虽然目前人们在铝中添加Ga、In、11、Zn、Sn、Mg、Hg等元素,研制出各种铝合金阳极,提高了铝阳极活化性能,但是这些研究本质上仍属于经验性的.到1983年Despic等人提出了“场…  相似文献   

12.
Electroreflection spectra of solid gallium in aqueous acidic solutions have a term associated with the electromodulation of the minimum distance abetween water molecules and the ionic core of the metal, which especially heavily affects the spectra at higher frequencies f mof modulation of potential E. The quantity da/dE –0.1 × 10–8cm/V is determined. Spectra obtained at low f mhave bands corresponding to charge transfer in the surface complexes formed during water chemisorption.  相似文献   

13.
On the basis of a model put forward, experimental data on the electrochemical ionization of solid gallium in carbonate buffer media are analyzed. It is shown that the formation on the electrode of a matrix consisting of the hydrolysis products of gallium ions Ga(3+) is the initial anodic step. The charge transport in this matrix proceeds via an ejection mechanism. At pH > 10, this matrix transforms into a reaction layer, which supplies Ga(OH)2CO3 -complexes (at higher pH—Ga(OH)4 -anions) to the electrolyte.  相似文献   

14.
The corrosion behavior at 25°C of tin plate, used for canning, in synthetic and natural brine solutions employed in storage of a number of food products (legumes) was studied.  相似文献   

15.
卡尔曼滤波荧光分析法用于铝,镓的同时测定   总被引:4,自引:0,他引:4  
研究了SPAEC荧光螯合反应并结合卡尔曼滤波校正的高灵敏度高选择性荧光分析法.在荧光分析中首次用卡尔曼滤波以分辨铝、镓与SPAEC螯合物的重叠峰;提出了适于荧光分析的几种滤波方式,并讨论了各自的特点.该法用于铝与镓(1:40~14:1)混合物分析,改善了灵敏荧光法(及试剂)的选择性.  相似文献   

16.
Reaction of Aluminum with Dilute Aqueous NaOH Solutions   总被引:1,自引:0,他引:1  
Reaction of aluminum powder and foil with dilute aqueous NaOH solutions was studied. The kinetic characteristics of the process were determined, and its mechanism was discussed.  相似文献   

17.
本文合成了2种第三主族金属铝和镓咔咯配合物Al(tpfc)、Ga(tpfc)、Al(tpfc)(Py)2、Ga(tpfc)(Py)。测定了在甲苯溶液中,铝和镓咔咯的电子光谱、荧光光谱、荧光量子产率及荧光寿命。在不同溶剂作用下,铝和镓咔咯的电子吸收光谱和荧光光谱的峰位置和强度存在差异。在二氯甲烷溶液中,轴向配体吡啶能促进铝和镓咔咯的π-π堆积。不同轴向配体与金属咔咯的结合能力为:咪唑>4-甲基咪唑>吡啶,铝比镓的咔咯配合物有更强的结合轴向配体的能力。  相似文献   

18.
Abstract

The thermodynamics of complexation of gallium by tricatechol ligand analogues of enterobactin and the kinetics of gallium removal from human serum transferrin (Tf) by one of those ligands have been studied by UV spectrophotometry. The ligands are a sulfonated monomeric catechoylamide, DMBS (N,N-dimethyl-2,3-dihydroxy-5-sulfonatobenzamide), and four sulfonated triscatechoylamides, MECAMS (1,3,5-N,N',N”-tris(5-sulfonato-2,3-dihydroxybenzoyl)-triaminomethylbenzene), Me3MECAMS (N, N', N-trimethyl-MECAMS), 3,4-LICAMS (N, N', N”-tris(5-sulfonato-2,3-dihydroxybenzoyl)-1,5,10-triazadecane), and (DiP)LICAMS (N, N”-diisopropyl-LICAMS). The individual orthohydroxyl protonation constants are 7.15 (DMBS), and (average values for the three protons of the tricatechols) 7.09 (MECAMS), 7.01 (LICAMS), 7.62 (Me3MECAMS), and 7.75 ((DiP(LICAMS), in good agreement with average values obtained potentiometrically. The overall formation constants for binding of Ga3+ by these ligands are β113 = 41.9 for DMBS, β110 = 41.1 for LICAMS, 36.6 for (DiP)-LICAMS, and 39.1 for Me3MECAMS. Gallium is removed from the two metal binding sites of Ga2Tf in a process by 3,4-LICAMS that is first order in both Tf and ligand at different rates (277M?1 min?1 and 17M?1 min?1). These are 12 and 3.4 times the corresponding rates of iron removal from Fe2Tf. The dissociation pathways of the gallium-ligand complexes upon protonation of the ligands were probed by whole spectrum analysis with the non-linear least-squares program REFSPEC. For all three triscatechoylamide complexes, protonation occurs in sequential one-proton reactions wth logK MLHn (n = 1, 2, 3) equal to 5.93, 5.00, 2.4 for MECAMS: 5.8, 5.7, 3.0 for 3,4-LICAMS; 6.81,6.34, 3.0 for Me3MECAMS; 6.34, 6.33, 4.3 for (DiP)LICAMS. First- and second-derivative spectra show that for complexes of trimeric ligands the last two protonations result in a complex with a completely dissociated catecholate arm, Ga(cat)2-catH2, similar to the Ga(DMBS)2 complex observed with the monomer. In the linear complexes, the middle ligand arm is detached from the metal first. Addition of a fourth proton resulted in decomposition of the gallium-trimeric ligand complex.  相似文献   

19.
提出了一个醇与水混和的热力学模型,它由三步组成,分别考虑了醇与水的物 理混合,醇和水的自缔合破坏以及它们间的交叉缔合.据此建立了一个超额焓方程 .检验的结果表明,它能满意地描述含醇水溶液的超额焓随组成和温度的变化规律.  相似文献   

20.
The current upswing in the interest in organoelement chemistry of Group 13 metals is attributed not least to the establishment of the coordination chemistry of RaE fragments (E=Al, Ga, In; a=1, 2) at d-block metals (M). Recently the availability of low-valent organoelement compounds as building blocks for synthesis has substantially enriched the structure chemistry of this class of compounds. The M–E bonding conditions and the question of the significance of M(dπ)-E(pπ) backbonding as well as potential applications in materials science, for example, as single-source precursors for the deposition of thin intermetallic films by chemical vapor deposition, are discussed.  相似文献   

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