Alkaline flux

McCauley S, DePaolo DJ (1997) The marine Sr/ Sr and records, Himalayan alkalinity fluxes and Cenozoic climate models. In Tectonic Uplift and Climate Change. Ruddiman WF (ed) Plenum, New York, p 427-467... 

Figure 8 Summary of the ratio of CaCOs dissolved and organic material oxidized for bottom chamber deployments in the northeastern Pacific, Ontong-Java Plateau, Ceara Rise, Cape Verde Plateau, northwestern Atlantic continental rise and California borderland basins (R. A. Jahnke and D. B. Jahnke, 2002). The absence of measurable alkalinity fluxes from high-CaCOs sites bathed in supersaturated bottom water appears to be inconsistent with observations...

Although Berelson et al. (1994) report chamber-based alkalinity fluxes from high-calcite sediment, the sites at which their studies were performed are very likely bathed in calcite-undersaturated bottom water. If so, coatings would not be expected to form. 

Another procedure uses an alkaline flux method with lithium metaborate (41), and involves diluting the fused portion in nitric acid. Interferences and interelement effects must be eliminated by calibration of samples and standards of similar composition. A procedure used successfully in the analysis of archaeological ceramics is described by Gritton (19). The sample is decomposed with hydrofluoric acid and perchloric acid, fumed to a moist residue, treated twice more with perchloric acid, dissolved in more perchloric acid, and diluted with water. 

The solid support for a liquid phase should have a high specific surface area that is chemically inert but wettable by the liquid phase. It must be thermally stable and available in uniform sizes. The most commonly used supports are prepared from diatomaceous earth, a spongy siliceous material. They are sold under many different trade names. Chromosorb W is diatomaceous earth that has been heated with an alkaline flux to decrease its acidity it is light iu color. Chromosorb P is crushed firebrick that is much more acidic than Chromosorb W, and it tends to react with polar solutes, especially those with basic functional groups. 

For a long time it was not possible to calculate the benthic total carbon dioxide or alkalinity flux because of artifacts introduced by decompression processes during core recovery. Moreover there... 

It is only necessary to liquate the rich sulphide ore and to oxidise the poor sulphide ore in order to obtain the sulphide and the oxide required for the production of the metal. Refining can be effected with an alkaline flux. 

Goodchemicalresistance, especially to acidic fluxes, except HF and H,P04 somewhat attacked by strongly alkaline fluxes Vessel material for metallic, alloy and salt melts up to 1250 C... 

Attacked by alkaline fluxes. With melts low In carbon and containing Fe or Nt, possibility of carbonization this can be prevented by an Interior lining Vessels for all metallic melts, except electron metal... 

Chemical methods for the detection and estimation of phosphorus in a compound are many and varied, but they usually require the phosphorus to be first obtained in the form of inorganic orthophosphate. For this, a prior oxidation and/or hydrolysis may have to be carried out. Insoluble phosphates are dissolved in mineral acids, with boiling if necessary. In some cases, fusion with alkaline fluxes (e.g. boric acid and sodium carbonate at lOOO C) is needed, followed by water or acid extraction of the soluble phosphates produced. Cation exchange resins may sometimes be used to convert insoluble into soluble phosphate salts. Numerous extraction and clean-up procedures have been prescribed for determination of the P content of compounds of bio origin. Pre-treatment of the sample by chemical methods is sometimes a necessary procedure before examination by physical methods (e.g. spectrophotometty), can be undertaken. 

The most commonly used supports are derived from diatomaceous earth and tefion. They are sold under many trade names depending on their pretreatment. The diatomaceous earth supports may be either Firebrick derived materials, such as Chromosorb P (a form of crushed commercial firebrick) and Gas Chrom R, or materials derived from filter aids, which Include Chromosorb W (diatomaceous earth heated with an alkaline flux), Anakrom ABS, and Gas Chrom Q. Some other solid supports are known by the trade names Celite 545, Phasep P, Embacel etc., (ail diatomaceous earth derived). Table 11.5 lists properties of some principal types of solid supports. 

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