Plasma aluminum

House RA. 1992. Factors affecting plasma aluminum concentrations in nonexposed workers. J Occup Med 34 1013-1017. 

Sharp CA, Perks J, Worsfold M, et al. 1993. Plasma aluminum in a reference population The effects of antacid consumption and its influence on biochemical indices of bone formation. Eur J Clin Invest 23 554-560. 

Tsou VM, Young RM, Hart MH. 1991. Elevated plasma aluminum levels in normal infants receiving antacids containing aluminum. Pediatrics 87 148-151. 

Etiology 1) Ingestion of A1 with citrate by kidney patients 2) Dialysate water >600-1000 pg/L 3) Marked rise in plasma aluminum with desferrioxamine treatment... 

Aluminum is used as a metallization material in current microelectronic devices. It can be etched by chlorine containing plasmas, provided that the native aluminum oxide is removed. This is accomplished with oxide scavengers such as BCI3 added to the plasma. Aluminum etching is isotropic in fact a clean aluminum surface reacts with atomic and molecular chlorine even in the absence of a plasma [225]. Anisotropy is achieved by the wall passivation mechanism (Fig. 16d). 

Dihydropteridine reductase is an important enzyme in the synthesis of several important neurotransmitters, such as tyrosine and acetyl choline. They found that erythrocyte levels of dihydropteridine reductase activity were less than predicted values, and correlated with plasma aluminum levels (Altmann et ah, 1987). After treatment with desferrioxamine, red cell dihydropteridine reductase activity levels doubled. Although brain levels of dihydropteridine reductase activity were not evaluated, it was suggested that high brain aluminum levels might lead to decreased availability of dihydropteridine reductase in the brain. It has been suggested that the mere presence of an increased body aluminum burden has an adverse effect on overall mortality (Chazan et al, 1988). More specifically, an increased body aluminum burden (estimated by the desferrioxamine infusion test) has been associated with memory impairment and increased severity of myoclonus with decreased motor strength (Sprague et al., 1988). 

After a relatively quick intake of aluminum into the intestinal walls its transition into the blood is significantly slower. In plasma aluminum is bound to approximately 80% to proteins, especially to transferrin. The amount considered currently as normal is 5 p,g/liter. Aluminum can be detected in all human organs. The only organs in which the aluminum concentration rises with progressing age are the lungs and the hilus lymphatic glands. 

Celik H, Cehk N, Kocyigit A, DikiUtas M. The relationship between plasma aluminum content, lymphocyte DNA damage, and oxidative status in persons using aluminum containers and utensils daily. Clin Biochem 2012 45(18) 1629-33. 

Fig. 4. Examples of emission spectrometry as a diagnostic monitoring tool for plasma processing, (a) The removal of chlorine contamination from copper diode leads using a hydrogen—nitrogen plasma. Emissions are added together from several wavelengths, (b) The etching and eventual removal of a 50-p.m thick polyimide layer from an aluminum substrate, where (x ) and (° ) correspond to wavelengths (519.82 and 561.02 nm, respectively) for molecular CO2...

Aluminum is best detected quaUtatively by optical emission spectroscopy. SoHds can be vaporized direcdy in a d-c arc and solutions can be dried on a carbon electrode. Alternatively, aluminum can be detected by plasma emission spectroscopy using an inductively coupled argon plasma or a d-c plasma. Atomic absorption using an aluminum hoUow cathode lamp is also an unambiguous and sensitive quaUtative method for determining alurninum. 

Quantitative aluminum deterrninations in aluminum and aluminum base alloys is rarely done. The aluminum content is generally inferred as the balance after determining alloying additions and tramp elements. When aluminum is present as an alloying component in alternative alloy systems it is commonly deterrnined by some form of spectroscopy (qv) spark source emission, x-ray fluorescence, plasma emission (both inductively coupled and d-c plasmas), or atomic absorption using a nitrous oxide acetylene flame. 

Other methods iaclude hydrogen reduction of TiCl to TiCl and TiCl2 reduction above the melting poiat of titanium metal with sodium, which presents a container problem plasma reduction, ia which titanium is collected as a powder, and ionized and vaporized titanium combine with chlorine gas to reform TiCl2 on cool-down and aluminum reduction, which reduces TiCl to lower chlorides (19,20). 

Inductively coupled argon plasma (icp) and direct current argon plasma (dcp) atomic emission spectrometry are solution techniques that have been appHed to copper-beryUium, nickel—beryUium, and aluminum—beryUium aUoys, beryUium compounds, and process solutions. The internal reference method, essential in spark source emission spectrometry, is also useful in minimizing drift in plasma emission spectrometry (17). Electrothermal (graphite... 

Fig. 14. RAIR spectra of a plasma polymerized silica-like film deposited onto a polished aluminum substrate (A) before and (B) after annealing at ISO C for 30 min. Film thickness was about 735 A. Reprinted by permission of Gordon and Breach Science Publishers from Ref. [15].

Despite the progress outlined in this chapter, much work remains to be done in the metal surface preparation arena. For example, there is still no ideal surface preparation method that does for steel what anodization processes do for aluminum and titanium. The plasma spray process looks encouraging but because it is slow for large areas and requires rather expensive robot controlled plasma spray equipment, its use will probably be limited to some rather special applications. For more general use, the sol-gel process has potential if future studies confirm recently reported results. 

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