Aluminum deposition system

Santos F, Chan JCM, Yang MS, et al. 1987. Aluminum deposition in the central nervous system. Preferential accumulation in the hippocampus in weanling rats. Med Biol 65 53-55. 

Yasui M, Yase Y, Ota K, et al. 1991. Aluminum deposition in the central nervous system of patients with amyotrophic lateral sclerosis from the Kii peninsula of Japan. Neurotoxicology 12 615-620. 

The AI,X7 is a strong Lewis acid, with X as its conjugate Lewis base. Hence, at Z > m, the melt is termed basic, while at Z < zn it is acidic, and at m = l the melts are neutral. Aluminum deposition occurs in these systems by the following reactions [455] ... 

GOLD. The deposition of gold onto polyimide (Fig. 4b and Table IV) is also observed to reduce the carbonyl Cls peak intensity (peak 2 of Cls in Table III) as well as that of the aromatic it - ir Cls (peak 1 of Cls), an effect analogous to that observed for the aluminum-polyimide system. New components also appear at lower energies in the 01s spectrum and there is an isoimide-like component in the Nls spectrum (peak 3). Gold is not generally known to exist in a stable complex form (marginal chemical reactivity) and is... 

The final performance limitation of aluminum alkyl electrolyte systems has not, by far, been reached. Substantially higher deposition rates than those realized today by eletrodeposition technology with organoaluminum electrolytes, i.e., 1-1.5 A/dm, are probably attainable [130]. As a result, the industrial efficiency of both galvanic aluminum deposition and eletrolytic aluminum refinement may be improved. 

Consequently, in early 1953, research on these complex compounds was initiated to determine whether they were suitable for electrolytic aluminum deposition. The first trials ended in disappointment, because the electrolytes, employed as melts, yielded useless aluminum coatings containing large portions of alkali metal. Besides, the electrolytes showed a very low conductivity compared to aqueous systems. Attempts to improve the quality of the aluminum deposits by adding excess triethylaluminum led to unexpected observations. Hence, a detailed investigation of alkali metal fluoride-aluminum trialkyl systems was necessary. 

Fig. 1 shows one of the first electrolytically deposited alumimun coatings to be obtained from this type of electrolyte. Since electrolytic aluminum deposition from this system has no true smoothening effect, thick layers become even rougher, as illustrated by the thickly coated cathode plate shown in Fig. 1. The cathodic deposition and the anodic dissolution of aluminum corresponded to almost 100 <7o of the amount expected according to the Faraday rule, which is an important prerequisite for even considering using this electrolysis technique for technical applications. Independently of the layer thickness, the deposited aluminum layers are found to be ectraordinarily pure. Spectroscopic investigations have revealed purities of up to 99.999%. Even when relatively impure raw aluminum with purities of 99.7% functions as the anode, very pure aluminum can be deposited. Therefore, obviously not only a technique of electroplating aluminum was discovered, but also a method of...

A series of article abstracts about various magnesium-deficiency symptoms, syndromes, conditions, or diseases are supplied at http //www.mgwa-ter.com/abstract.shtml. These include the following alcohol-related hypertension and strokes, alcohol-induced contraction of cerebral arteries, amyofrophic lateral sclerosis and aluminum deposition in the central nervous system, cardiac arrhythmias, asthma therapy, attention deficit disorder (ADD), cerebral artery disorders, constipation, diabetes, heart muscle disorders or myocardial infarction, hypertension, HIV, kidney stones, menopause, migraine, multiple sclerosis, osteoporosis, and premenstrual syndrome. In all cases, an increase in magnesium levels had beneficial effects. 

X-ray and electron diffraction patterns of the cerium-poor as-deposited films exhibit an aluminum ring system and a large halo relative to an amorphous material. By annealing inside the electron microscope a new ring system appears which is characteristic of small crystallites and can be indexed as a hexagonal structure with a = 6.92 A and c = 6.28 A. No compounds of the CeAl system are related to these parameters. Upon further heating this alloy, which is very unstable, disappears and the formation of large aluminum crystals are observed. 

The X-ray diffraction patterns of the as-deposited GdAl films, heated on their substrates at 570 and 720 K, show the coexistence of the aluminum ring system and a broad halo. By annealing inside the electron microscope a number of... 

Metallization layers are generally deposited either by CVD or by physical vapor deposition methods such as evaporation (qv) or sputtering. In recent years sputter deposition has become the predominant technique for aluminum metallization. Energetic ions are used to bombard a target such as soHd aluminum to release atoms that subsequentiy condense on the desired substrate surface. The quaUty of the deposited layers depends on the cleanliness and efficiency of the vacuum systems used in the process. The mass deposited per unit area can be calculated using the cosine law of deposition ... 

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