Migration of incorporated phosphorus in the anodic oxide film formation of tantalum

The mobility of phosphorus incorporated as a mass marker into tantalum anodic oxide films was investigated by means of ion microprobe mass analysis. If the transport number of tantalum ions for the film formation is assumed to be constant regardless of the oxidation current density chosen, then conclusions are drawn that the incorporated phosphorus is mobile, and that the migration rate of it is high for a high oxidation current density. The apparent degree of migration of the incorporated phosphorus was evaluated as a function of the current density for the anodization, on the assumption that the transport number of tantalum ions was 0.243.     

Luminescence,breakdown and colouring of anodic oxide films on aluminium

El and Pl, breakdown and self-colouring phenomena of anodic oxide films on aluminium, which have been found to be closely related with each other, were reviewed according to newly proposed classifications. Thus the hitherto unsolved problems which had caused confusion in complete understanding of the art are almost solved. Firstly galvanostatic anodic behaviours of Al were classified. Secondly it was shown that el is caused either by (1) selected impurities (activators) (Mn, Eu etc) in Al, (2) excited carboxylate ions in the film formed in aliphatic carboxylic acids, or (3) by, ‘flaws’ in the case of el in inorganic electrolytes, which is not the el in the true sense. Thirdly pl is to be seen in aliphatic carboxylic acid films only and the luminescent centres are the same with those of el in the acid. Aromatic acid films show neither el nor pl since the acid can not enter into the films. Further, reference was made to one type of solid-type led (Al—Al₂O₃-SnO₂) constructed. Fourthly, breakdowns have been classified into: (1) electrochemical breakdown including porous film formation, carboxylate breakdown (pitting) and chloride breakdown, and (2) ‘electric breakdown during anodizing’ or ‘electrolytic breakdown’ which is a complicated mixture of electrochemical and electric breakdown at/or through oxide—electrolyte interface, and which includes ‘burning’ (luminescent ‘flame’ propagation process) and sparking (scintillation and arcing). Finally self-colouring of ‘pure’ Al (except colouring by alloying elements or impurities included) has been classified into: (1) colouring by decomposition or cyclisation of excited carboxylate ions in the film (post-el) higher electric field attained across the film. Thick, coloured films show no more el nor pl. (2) colouring by existence of Al⁰ particles in the interstitial positions of the film by high electric field assisted oxide growth in the case of the so-called ‘hard anodizing’, locally grown coloured spots in inorganic acid, eg sulphuric acid, and of so-called integral colour anodizing in sulphonated aromatic dibasic acid (or higher aliphatic carboxylic acid) plus a small amount of sulphuric acid, typically Kalcolor, Duranodic 300 or Permalux processes for architectural use. These films show neither el nor pl.     

Anodic chlorine/nitrogen co-doping of reduced graphene oxide films at room temperature

Room temperature simultaneous doping of reduced graphene oxide films with oxygen, nitrogen and chlorine was performed through anodic polarization in a neutral nitrogen-deaerated KCl electrolyte. The thermodynamic electrochemical windows of water, dissolved nitrogen and chlorine anions were analyzed on the basis of the Pourbaix diagram. Anode polarization demonstrated that the nitrogen, water and chlorine anions can be oxidized at an applied potential of 1.7 V vs. NHE. The oxidative products, i.e. oxygen, nitrate anion and hypochlorous acid, can react with the reduced graphene oxide surface. X-ray photoelectron spectroscopy proved the chlorine–nitrogen co-doping of the treated film, along with an increase of oxygen groups. Surface structure evolution was also confirmed by Raman and Fourier-transform infrared spectroscopies. The anodic doping can be hindered by covering the reduced graphene oxide surface with sulfate anions or forming stable carbon–nitrogen bonds. Incorporation of oxygen, nitrogen and chlorine also helps to enhance the supercapacitance of the doped film.     

Anodization of Al–Nd alloy films in nonaqueous electrolyte solutions for TFT-LCD application

The anodization behavior of Al–Nd alloys in nonaqueous electrolyte solutions and the electronic properties of the resultant anodic oxide films were studied for TFT-LCD application. Sputtered Al–Nd alloy films on glass substrates were anodized at 25 °C and 1 mA cm⁻² up to 100 V in ethylene glycol–water solutions containing 10 wt.% ammonium tartrate or salicylate to give uniform and flat oxide films. The incorporation of organic components into the anodic oxide films from the electrolyte solutions has lowered the relative permittivity and increased the breakdown electric field of the oxide films. This was performed by decreasing the water content in the electrolyte solutions. The tartrate solution caused higher carbon incorporation than the salicylate counterpart at the same water concentrations, giving lower relative permittivity, and higher forward breakdown electric field. The AlO stretching frequency of the oxide films decreased slightly as the amount of incorporated organic moieties increased. Nd was uniformly distributed in the oxide films and an increase in the Nd content was likely to increase both the relative permittivity and the forward breakdown electric field without any apparent change in the anodization behavior.     

The distribution of antimony in the oxide layer formed by potentiostatic oxidation of Pb-Sb alloy

The distribution of antimony within the oxide films on Pb-Sb alloy prepared by potentiostatic oxidation in H₂SO₄ solutions was examined by SIMS. The study of oxide films prepared by applying different potentials for three hours showed that two types of film were obtained depending on whether the potential was more negative or more positive than 1·5 V. Antimony profiles were obtained for films at several stages in the initial growth. It was found that antimony was retained in the oxide film at 1·5 V during both nucleation and two- or three-dimensional growth of PbO₂ and at 1·6 V during the lateral overlaps of three-dimensional centres of PbO₂. Relationships between the antimony distribution profiles and the oxide film growth are discussed.     

对氨基苯甲醚工业品精制方法的选择

对氨基苯甲醚是一种重要的医药、染料及化工产品原料。受生产工艺、原料、生产条件的限制,对氨基苯甲醚工业品中含有一定量有机、无机的含氯、含硫化合物等杂质,对下游工艺催化剂产生不利影响。根据对氨基苯甲醚工业品中杂质硫、氯的存在方式,分析了比较适合该体系的精制方法,选择可行的对氨基苯甲醚工业品精制方法。     

Anodic film growth on tantalum in dilute phosphoric acid solution at 20 and 85 °C

The effects of current density and temperature on the anodic films formed on tantalum in dilute H₃PO₄ (0.06%wt) solution have been studied by transmission electron microscopy, using ultramicrotomed sections, and Rutherford backscattering spectroscopy. Two-layered films have been identified, comprising an inner relatively pure Ta₂O₅ layer, adjacent to the metal/film interface, and an outer layer containing incorporated PO₄³⁻ anions. The total amount and depth of incorporated phosphorus species increase with increasing current density and decreasing temperature, in correspondence with the enhancement of the electric field. The formation conditions for the films include those relevant to the commercial anodising of tantalum for capacitors for which the extent of phosphorus incorporation is shown to be comparatively low.     

ITO薄膜的研究进展

ITO是锡掺杂氧化铟薄膜的简称,属于透明导电氧化物材料。常规沉积方法制备的ITO薄膜通常为非晶态或体心立方晶系晶体,为n型半导体材料,其载流子为自由电子,主要来源于沉积过程中薄膜化学计量比偏离或阳离子掺杂形成的施主杂质。ITO薄膜是当前研究和使用最为广泛的透明导电氧化物薄膜材料,由于具有低电阻率、高可见光透过率、高红外反射率等独特物理特性而被大量应用于平板显示器、太阳能电池、发光二极管、气体传感器、飞机风挡玻璃除霜器等领域。此外,ITO薄膜对微波还具有高达85%的衰减作用,因而在电磁屏蔽等军用领域显示出巨大的潜在应用价值。过去几十年里,针对ITO薄膜的研究工作主要聚焦于薄膜的光电性能上。当前,伴随着ITO薄膜的应用范围在航空航天和军用武器装备等领域的拓展,ITO薄膜在恶劣力学环境中的使用日渐增多。因此,除光电性能外,ITO薄膜的力学性能也开始受到研究者越来越多的关注,人们对薄膜器件在各类恶劣使用环境中的稳定性及耐久性提出了更高的要求,这一要求使得对ITO薄膜力学性能的深入研究分析有了重要的理论及实际意义。本文综述了近年来ITO薄膜在微结构特性、能带结构、光电性能及力学性能等方面的研究进展,简略探讨了ITO薄膜的研究发展方向。     

Er2O3高介电常数薄膜的结构和介电性能的研究

采用射频磁控反应溅射技术,在不同的Ar：O2条件下制备Er2O3薄膜,然后把样品分别在600、700和800℃退火60min,研究分析了Ar：O2比例和退火温度对样品的结构和介电性能的影响。结果表明：600℃以上退火处理后,Er203薄膜从非晶态转变为多晶,使薄膜的介电常数和击穿场强明显增加,漏电流密度减小,但不同的退火温度对这些性能的影响不大,退火温度的提高会在Si和Er2O3薄膜的界面形成类SiO2过渡层。但Ar：O2比对薄膜的结晶性能和介电性能影响不大,但工作气体中较少的Ar会导致在Si和Er2O3薄膜的界面形成类Si02过渡层。     

Structure Evolution of Highly Crystallized BaWO4 Film Prepared by an Electrochemical Method at Room Temperature

Highly crystallized BaWO₄ films have been prepared on a tungsten substrate in an alkaline solution containing barium ions by an electrochemical method with a constant direct current density of 1 mA/cm² at room temperature (25°C). The average grain size was about 13 μm, and the thickness about 9 μm after a treatment time of 35 min. The dependence of cell voltage on deposition time was divided into three steps: conduction, anodic oxidation, and breakdown steps. The BaWO₄ film formed during the first step. Electrochemical dissolution of metal tungsten occurred with an accompanying positive change of overpotential in the first step. The crystallization of BaWO4 was characterized by three-dimensional nucleation. In the second step, an amorphous tungsten oxide film formed, thereby increasing the potential. An electrical breakdown occurred in the third step, and the breakdown voltage (about 90 V) was practically the same as those of anodic tungsten oxide films.     

Investigation into the microstructure and phase composition of polycrystalline lead selenide films in the course of thermal oxidation

The formation of oxide phases during thermal oxidation of doped polycrystalline lead selenide films is investigated as a function of the temperature-time conditions of annealing and introduced impurities. It is demonstrated that the microstructure and phase composition of the films doped with bismuth are characterized by evolutionary changes in the course of annealing. During heat treatment of lead selenide films doped with iodine, the microstructure of the film undergoes a drastic transformation of the “encapsulation” type and, simultaneously, the phase composition changes sharply.     

由硫磺、氯气一步法制备二氯化硫

以工业硫磺和液氯为主要原料,一步法直接制备二氯化硫。确定了合成反应最佳工艺条件：起始反应温度１００～１１０℃,氯气通入时间（即反应时间）６ｈ,通氯气量７５Ｌ／ｈ,精制蒸馏温度６０～６５℃,稳定剂三氯化磷用量０．１％～０．３％。在此工艺条件下制备的二氯化硫收率可达８０％以上。     

航煤液相加氢产品腐蚀性因素分析及对策

航煤产品铜片腐蚀主要与某些活性硫化物和有机酸相关,这些活性硫化物主要包括元素硫、硫化氢、硫氢化铵、硫醇、硫的氧化物、磺酸和酸性磺酸酯等.另外,航煤产品中存在其他杂质,如碱性物质、氯化物等也能对铜片产生腐蚀.加氢精制后航煤原料中有机酸、硫醇和碱性物等基本脱除,但由于航煤原料中含有微量氮,加氢后能与硫、氯生成硫氢化铵和氯化...     

过冷降膜的换热特性和破断条件

本文在实验观测的基础上对垂直降膜的换热情性和破断临界现象进行了简化分析.据此整理实验数据,给出正常液膜和接近破断临界时的液膜对流换热努塞尔数综合关系式以及破断准则数综合关系式.     

Electrochemically grown passive films on carbon steel (SAE 1018) in alkaline sour medium

Corrosion films were prepared by applying cyclic potential pulses to the 1018 carbon steel-sour medium interface (1 M (NH₄)₂S, 500 ppm CN⁻) for 1 min. Electrochemical behavior and surface morphology of these films were determined using electrochemical impedance spectroscopy (EIS), scanning electron microscopy, and scanning photoelectrochemical microscopy (SPECM). EIS diagrams and SPECM images show the passive properties and homogeneity of the films. Furthermore, X-ray photoelectron spectroscopy (XPS) was used to characterize their chemical nature and structure. XPS results show that different oxide and sulfur structures were developed during the electrochemical oxidation of carbon steel in concentrated sour media. The analysis of O 1s data indicated that, during film growth, H₂O and/or hydroxyl groups are incorporated into the film structure. The XPS spectra of Fe 2p show iron bonds with S as iron sulfide (FeS₂ and FeS) and the corresponding peak of O 1s shows those bonds with oxygen as Fe₂O₃ and/or FeO. XPS depth profile analyses for the film showed that the ratio of FeS and FeO increases from film surface to film-carbon steel interface. This corroborates the diffusion of iron ions through the film during its electrochemical growth. The chemical shift through the film for the peak associated with Fe 2p signal proves that transport mechanism of iron ions through the film is carried out by chemical diffusion.     

O,O-二乙基硫代磷酰氯生产残液的成分解析

通过气质联用方法,对O,O-二乙基硫代磷酰究.经定性分析发现:1#的残液中主要包括氯乙烷等A～L 12种杂质.从其结构上分析,如果要提高1#的总收率,则可在生产过程中控制氯气的用量、控制五硫化二磷的质量、降低蒸馏温度、提高真空度.     

Importance of water content in formation of porous anodic niobium oxide films in hot phosphate-glycerol electrolyte

Niobium has been anodized at a constant current density to 10 V with a current decay in 0.8 mol dm⁻³ K₂HPO₄-glycerol electrolyte containing 0.08-0.65 mass% water at 433 K to develop porous anodic oxide films. The film growth rate is markedly increased when the water content is reduced to 0.08 mass%; a 28 μm-thick porous film is developed in this electrolyte by anodizing for 3.6 ks, while the thickness is 4.6 and 2.6 μm in the electrolytes containing 0.16 and 0.65 mass% water respectively. For all the electrolytes, the film thickness changes approximately linearly with the charge passed during anodizing, indicating that chemical dissolution of the developing oxide is negligible. SIMS depth profiling analysis was carried for anodic films formed in electrolyte containing ∼0.4 mass% water with and without enrichment of H₂¹⁸O. Findings disclose that water in the electrolyte is a predominant source of oxygen in the anodic oxide films. The anodic films formed in the electrolyte containing 0.65 mass% water are practically free from phosphorus species. Reduction in water content increased the incorporation of phosphorus species.     

Electroluminescence of Al/anodic alumina/electrolyte system and non destructive electronic avalanche

Luminescence during the growth of “flaw-free” films on high purity aluminium by anodizing is inherent to the aliphatic carboxylic acid film, as opposed to the typical inorganic, ammonium borate film, and is specified as an “impact type” electroluminescence. Carboxylate ions incorporated act as luminescent centres of the film. The strong dependence of the intensity of luminescence upon the film thickness can reasonably be explained by introducing the concept of non-destructive avalanching, which is uniformly distributed over the entire surface of the anode, and further by assuming that all the electrons involved in the multiplication in the oxide film contribute to the luminescence.     

喷雾热分解法制备ZnO系低压压敏薄膜

首次利用喷雾热分解法成功地制备出低压ＺｎＯ压敏薄膜。沉积温度３５０℃,沉积时间２ｈ;退火温度６５０℃,退火时间１ｈ。Ｘ射线分析表明薄膜经退火后已良好晶化。其非线性系数α为８．０９;压敏电电压Ｖ１ｍＡ为１３．１５Ｖ。实验表明通过制备ＺｎＯ薄膜可得到较低的压敏电压。     

Infrared Spectroscopy of Interphases Between Model Rubber Compounds and Plasma Polymerized Acetylene Films

Thin (～ 750 Å) plasma polymerized films of acetylene deposited onto polished steel substrates are promising primers for rubber-to-metal bonding. The as-deposited films contained mono- and di-substituted acetylene groups, aromatic groups, and groups such as carbonyl which apparently resulted from reaction of residual free radicals with oxygen when the films were exposed to the atmosphere. There was some evidence for formation of acetylides in the interphase between the films and the substrates. Reactions occurring in the interphase between the plasma polymerized films and natural rubber were simulated using a model “rubber” consisting of a mixture of squalene, zinc oxide, carbon black, sulfur, stearic acid, diaryl-p-diphenyleneamine, and N, N-dicyclohexyl-benzothiazole sulfenamide (DCBS). It was found that zinc oxide reacted with stearic acid to form zinc stearate in the interphase between squalene and the plasma polymerized acetylene primer. Zinc stearate reacted with DCBS and sulfur to form an accelerator complex and zinc perthiomercaptides. The perthiomercaptides reacted with squalene and the plasma polymer to form pendant groups which eventually reacted to form crosslinks between squalene and the primer. In the absence of cobalt naphthenate, the formation of pendant groups and eventually crosslinks was relatively slow and the length of the sulfur chains in the crosslinks and the pendant groups was relatively long. When cobalt naphthenate was added to the model “rubber,” the reactions in the interphase between squalene and the plasma polymerized film occurred much faster and the length of the crosslinks and the pendant groups was much shorter.