Tantalum anodes

Helium-ion induced X-ray spectrum from anodized tantalum (fluencei 1.5 X 10 HeVcmV ... 

In order to carry out depth profiling with AES, the sputtering rate must be determined. The sputtering rate is usually measured by determining the time required to sputter through a layer of known thickness. Anodized tantalum foils are convenient for this purpose since the oxide thickness can easily be controlled and since the interface between the metal and the oxide is relatively sharp [43]. 

Krembs, G.M. (1963) Residual tritiated water in anodized tantalum films. J Electrochem Soc 110 938-940... 

Figure 5. Anodized tantalum-sputtered glass slide on which normal intact plasma had resided for 12 min (more or less vertical zone from 1 to ) and where it had resided for a few seconds (area s, from to right...

In recent, unpublished experiments, the protein that platelets were suspended in appeared to determine to which film of protein they would adhere. For example, platelets suspended in albumin may adhere less to fibrinogen than to gamma-globulin films on glass or anodized tantalum. 

Where a surface forms in the blood that resembles anodized tantalum more than oxidized silicon, fibrinogen will also be deposited, and some of it, if the plasma remains intact, will be removed. However,... 

Figure 2. Fibrinogen left by intact plasma between convex lens and anodized tantalum-sputtered glass slide. Only right half of pattern was exposed to antiserum to fibrinogen (see text).

Johnson PE, Bernstein JJ, Hunter G, Dawson WW and Hench LL (1977) An in vitro and in vivo analysis of anodized tantalum capacitive electrodes corrosion response, physiology, and histology. J Biomed Mater Res 11 637-656. 

We detected the phenomenon e.g. by observing the interference color pattern left by protein drops landing on and rolling over ferric stearate polished anodized tantalum slides. 

Our own studies of human citrated intact plasma at activating surfaces (glass, anodized tantalum, oxidized silicon) resulted in the following findings. 

Anodic tantalum films can be formed in a wide range of electrolytes, allowing incorporation of appropriate species [57]. The mobility of various species, including... 

Ohm s law (Figure 15) was observed by Mead at room temperatures with films of anodic tantalum pentoxide up to quite high field strengths and over several decades of current (e.g., to 10 A/cm at 0.5 x lO V/cm with 110 A films). Mead favored... 

J.D. Sloppy, Z. Lu, E.C. Dickey, D.D. Macdonald, Growth mechanism of anodic tantalum pentoxide formed in phosphoric acid, Electrochim. Acta 87 (1) (2013) 82-91. 

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