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Calcium cadmium and

Plette, A. C. C., Benedetti, M. F. and van Riemsdijk, W. H. (1996). Competitive binding of protons, calcium, cadmium, and zinc to isolated cell walls of a grampositive soil bacterium, Environ. Sci. Technol., 30, 1902-1910. [Pg.266]

The data cited in the survey [93], where the synergic action of hydrogen chloride acceptors — salts of barium and cadmium, calcium and zinc - is noted, as well as the data of [71, 73], which characterize the synergic action of mixtures of the stearates of lead, barium, calcium, cadmium, and zinc, can be cited as examples of mixtures of monotypic stabilizers. [Pg.186]

In addition to the three basic types of epoxide types enumerated, the literature contains data on the use of certain other substances containing epoxide rings in the molecules to stabilize polyvinyl chloride. Salts of lead, barium, calcium, cadmium, and aliphatic epoxy acids, with 11-22 carbon atoms in the chain, have been described. It has been shown that in contrast to salts of nonepoxided aliphatic acids, salts of epoxy acids give no synergic effect when they are used together [71]. [Pg.209]

Group IIB and know that this means the group of elements zine. cadmium and mercury, whilst Group IIA refers to the alkaline earth metals beryllium, magnesium, calcium, barium and strontium. [Pg.13]

Typically, soHd stabilizers utilize natural saturated fatty acid ligands with chain lengths of Cg—C g. Ziac stearate [557-05-1/, ziac neodecanoate [27253-29-8] calcium stearate [1592-23-0] barium stearate [6865-35-6] and cadmium laurate [2605-44-9] are some examples. To complete the package, the soHd products also contain other soHd additives such as polyols, antioxidants, and lubricants. Liquid stabilizers can make use of metal soaps of oleic acid, tall oil acids, 2-ethyl-hexanoic acid, octylphenol, and nonylphenol. Barium bis(nonylphenate) [41157-58-8] ziac 2-ethyIhexanoate [136-53-8], cadmium 2-ethyIhexanoate [2420-98-6], and overbased barium tallate [68855-79-8] are normally used ia the Hquid formulations along with solubilizers such as plasticizers, phosphites, and/or epoxidized oils. The majority of the Hquid barium—cadmium formulations rely on barium nonylphenate as the source of that metal. There are even some mixed metal stabilizers suppHed as pastes. The U.S. FDA approved calcium—zinc stabilizers are good examples because they contain a mixture of calcium stearate and ziac stearate suspended ia epoxidized soya oil. Table 4 shows examples of typical mixed metal stabilizers. [Pg.550]

Economics. As with the alkyl tin stabilizers, the market pricing of the mixed metal stabilizers tend to be directed by the particular appHcation. The calcium—zinc and barium—cadmium packages are typically used at 2.0—4.0 parts per hundred of PVC resin (phr) in the formulation. These completely formulated products are sold for 2.50— 4.40/kg for the Hquid products and 3.20— 6.50/kg for the soHds and pastes. The higher efficiency products aimed at rigid appHcations tend toward the higher end of the cost range. [Pg.551]

The basic metal salts and soaps tend to be less cosdy than the alkyl tin stabilizers for example, in the United States, the market price in 1993 for calcium stearate was about 1.30— 1.60, zinc stearate was 1.70— 2.00, and barium stearate was 2.40— 2.80/kg. Not all of the coadditives are necessary in every PVC compound. Typically, commercial mixed metal stabilizers contain most of the necessary coadditives and usually an epoxy compound and a phosphite are the only additional products that may be added by the processor. The requited costabilizers, however, significantly add to the stabilization costs. Typical phosphites, used in most flexible PVC formulations, are sold for 4.00— 7.50/kg. Typical antioxidants are bisphenol A, selling at 2.00/kg Nnonylphenol at 1.25/kg and BHT at 3.50/kg, respectively. Pricing for ESO is about 2.00— 2.50/kg. Polyols, such as pentaerythritol, used with the barium—cadmium systems, sells at 2.00, whereas the derivative dipentaerythritol costs over three times as much. The P-diketones and specialized dihydropyridines, which are powerful costabilizers for calcium—zinc and barium—zinc systems, are very cosdy. These additives are 10.00 and 20.00/kg, respectively, contributing significantly to the overall stabilizer costs. Hydrotalcites are sold for about 5.00— 7.00/kg. [Pg.551]

Reduction to Gaseous Metal. Volatile metals can be reduced and easily and completely separated from the residue before being condensed to a hquid or a soHd product in a container physically separated from the reduction reactor. Reduction to gaseous metal is possible for 2inc, mercury, cadmium, and the alkah and aLkaline-earth metals, but industrial practice is significant only for 2inc, mercury, magnesium, and calcium. [Pg.168]

Organophosphoms compounds, primarily phosphonic acids, are used as sequestrants, scale inhibitors, deflocculants, or ion-control agents in oil wells, cooling-tower waters, and boiler-feed waters. Organophosphates are also used as plasticizers and flame retardants in plastics and elastomers, which accounted for 22% of PCl consumed. Phosphites, in conjunction with Hquid mixed metals, such as calcium—zinc and barium—cadmium heat stabilizers, function as antioxidants and stabilizer adjutants. In 1992, such phosphoms-based chemicals amounted to slightly more than 6% of all such plastic additives and represented 8500 t of phosphoms. Because PVC production is expected to increase, the use of phosphoms additive should increase 3% aimually through 1999. [Pg.383]

H. 8-Hydroxyquinaldine (XI). The reactions of 8-hydroxyquinaldine are, in general, similar to 8-hydroxyquinoline described under (C) above, but unlike the latter it does not produce an insoluble complex with aluminium. In acetic acid-acetate solution precipitates are formed with bismuth, cadmium, copper, iron(II) and iron(III), chromium, manganese, nickel, silver, zinc, titanium (Ti02 + ), molybdate, tungstate, and vanadate. The same ions are precipitated in ammoniacal solution with the exception of molybdate, tungstate, and vanadate, but with the addition of lead, calcium, strontium, and magnesium aluminium is not precipitated, but tartrate must be added to prevent the separation of aluminium hydroxide. [Pg.444]

Thin-layer plates were made with silica gel-calcium sulfate and each contained a mixture of zinc silicate and zinc cadmium sulfide as phosphors. Separated components are generally visible under ultraviolet light by fluorescence quenching. This was true, in part, for the pyrethrins, except that some of the separated components possessed a natural fluorescence under the ultraviolet lamps. [Pg.63]

Heat stabilisers for PVC act by HC1 scavenging and include organotins, mixed metal salt blends, and lead compounds. The latter account for nearly 64 % of volume (in 1994), followed by barium/cadmium and organotin compounds. Cadmium-based heat stabilisers are rapidly being replaced due to environmental concerns. Barium/zinc and calcium/zinc compounds show a high growth rate. It is expected that methyltin stabilisers will soon dominate the growing PVC pipe market. [Pg.780]

The effects of the pH of the NaOAc-HOAc solutions on the subsequent fractions are related to the partitioning patterns of elements in soils. Calcium and Cd in the calcareous soils are predominately present in the CARB fraction (Banin et al., 1990). Cadmium and Ca in the CARB fraction of the soils studied accounted for 40-50% and 75-99%, respectively. Even NaOAc-HOAc solutions at pH 7.0 extracted 3-6% and... [Pg.118]

Shore, R.F., D.G. Myhill, E.J. Routledge, and A. Wilby. 1995. Impact of an environmentally-realistic intake of cadmium on calcium, magnesium, and phosphate metabolism in bank voles, Clethrionomys glareolus. Arch. Environ. Contam. Toxicol. 29 180-186. [Pg.76]

In mammals, cadmium inhibits copper absorption across the intestinal mucosa (Aaseth and Norseth 1986). Intercorrelations of copper with cadmium and zinc in livers of polar bears (Ursus maritimus) are probably mediated by metallothioneins, which may contain all three metals (Braune etal. 1991). In rats, copper protects against nephrotoxicity induced by cadmium, provided that copper is administered 24 h prior to cadmium insult. Specifically, rats given 12.5 mg Cu/kg BW by way of subcutaneous injection 24 h before receiving 0.4 mg Cd/kg BW — when compared to a group receiving Cd alone — did not have excessive calcium in urine and renal cortex or excessive protein in urine. Thus, 2.8 mg Cu/kg BW protects against 0.25 mg Cd/kg BW (Liu et al. 1992). [Pg.137]

Scheuhammer, A.M. 1996. Influence of reduced dietary calcium on the accumulation and effects of lead, cadmium, and aluminum in birds. Environ. Pollut. 94 337-343. [Pg.340]

The magnesium will be liberated quantitatively and may then be titrated with a standard EDTA solution. Where mixtures of metal ions are analysed, the masking procedures already discussed can be utilized or the pH effect exploited. A mixture containing bismuth, cadmium and calcium might be analysed by first titrating the bismuth at pH = 1-2 followed by the titration of cadmium at an adjusted pH = 4 and finally calcium at pH = 8. Titrations of this complexity would be most conveniently carried out potentiometrically using the mercury pool electrode. [Pg.213]

Calcium sulfate crystals were precipitated in a Continuous Mixed Suspension Mixed Product Removal (CMSMPR) crystallizer by mixing of calcium phosphate and sulfuric acid feed streams. The formed calcium sulfate hydrate (anhydrite, hemihydrate and dihydrate) mainly depends on the temperature and the solution composition. The uptake of cadmium and phosphate ions in these hydrates has been studied as a function of residence time and solution composition. In anhydrite, also the incorporation of other metal ions has been investigated. The uptake was found to be a function of both thermodynamics and kinetics. [Pg.381]

The aim of this work is to study the incorporation of cadmium and phosphate in the three calcium sulfate modifications. The uptake of other metal ions in AH will also be described. Kinetic effects of operating conditions such as the residence time, sulfuric acid and phosphate concentration upon the phosphate and cadmium uptake has been investigated. In addition the influence of a growth retarding impurity, AIF3, on the cadmium and phosphate uptake will be given. [Pg.384]

In the investigated range of conditions the uptake of cadmium and phosphate in calcium sulfate by isomorphous substitution can be described by a D-value. [Pg.394]

Physical Form, brown to black oily liquid new mineral-based crankcase oil contains petrochemicals (straight-chain hydrocarbons, aromatic hydrocarbons, and polyaromatic hydrocarbons or PAH) plus stabilizers and detergents including zinc dithiophosphate, zinc diaryl or dialkyl dithiophosphates (ZTDP), calcium alkyl phenates, magnesium, sodium, and calcium sulfonates, tricresyl phosphates, molybdenum disulfide, heavy metal soaps, cadmium, and zinc. ... [Pg.724]

Chronic exposure can result in obstructive lung disease, emphysema, and kidney disease. Cadmium may also be related to increases in blood pressure (hypertension) and is a possible lung carcinogen. Cadmium affects calcium metabolism and can result in bone loss. This condition has been referred to as Itai-Itai disease, which means Ouch-Ouch in Japanese and reflects the bone pain associated with cadmium effects on calcium. [Pg.127]

J. Benters, U. Flogel, T. Schafer, D. Leibfritz, S. Hechtenberg, D. Beyersmann, Study of the interactions of cadmium and zinc ions with cellular calcium homoeostasis using F-19-NMR spectroscopy, Biochem. J. 322 (1997) 793-799. [Pg.270]


See other pages where Calcium cadmium and is mentioned: [Pg.227]    [Pg.34]    [Pg.242]    [Pg.227]    [Pg.34]    [Pg.242]    [Pg.91]    [Pg.410]    [Pg.133]    [Pg.366]    [Pg.867]    [Pg.366]    [Pg.724]    [Pg.349]    [Pg.163]    [Pg.260]    [Pg.263]    [Pg.453]    [Pg.119]    [Pg.349]    [Pg.349]    [Pg.22]    [Pg.535]   
See also in sourсe #XX -- [ Pg.437 , Pg.438 ]




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Miscellaneous metals including sodium, lithium, ammonium, potassium, magnesium, calcium, lead, copper, cadmium, cobalt, nickel, iron, zinc and 14 lanthanides

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