Chloride calcium concentration

After drying over quicklime, calcium oxide CaO, the ammonia is collected by upward delivery. (N.B. Both of the common drying agents, calcium chloride and concentrated sulphuric acid, combine with the gas.)... 

Calcium sources, such as gypsum and lime, promote cation exchange from sodium clay to a less-sweUing calcium clay. Calcium concentrations ate normally low (<1000 mg/L) and osmotic swelling is only reduced if other salts are present. Calcium chloride has been used infrequently for this purpose but systems are available that allow high calcium chloride levels to be carried in the mud system (98). 

Calcium chloride solutions, typically employed at 2—5% concentration, are used as antispasmodics, diuretics (qv), and in the treatment of tetany. Concentrated solutions of calcium chloride cause erythema, exfoUation, ulceration, and scarring of the skin (39). Injections into the tissue may cause necrosis. If given orally calcium chloride can cause irrita tion to the gastrointestinal tract unless accompanied by a demulcent. There is no pubHshed information on mutagenicity or carcinogenicity caused by calcium ions or calcium chloride. Calcium chloride has been given a toxicity or hazard level 3 (40). Materials in this classification typically have LD q below 400 mg/kg or an LC q below 100 ppm. 

Other Considerations Autoignition can occur if combustible fluids are absorbed by wicking-type insulations. Chloride stress corrosion of austenitic stainless steel can occur when chlorides are concentrated on metal surfaces at or above approximately 60°C (140°F). The chlorides can come from sources other than the insulation. Some calcium sihcates are formulated to exceed the requirements of the MIL-I-24244A specification. Fire resistance of insulations varies widely. Calcium sihcate, cellular glass, glass fiber, and mineral wool are fire-resistant but do not perform equally under actual fire conditions. A steel jacket provides protection, but aluminum does not. 

Similar to the pH meter, gas meters employ specific ion electrodes. The electrodes generate a potential proportional to the activity of a specific ion in solution. The calibration is achieved in standard solution and results read in mV or concentration in mg/L or ppm on the meter. The water can be adapted to monitor the concentration of carbon dioxide, hydrogen sulfide, ammonia, chloride, calcium, potassium and sodium to name a few. 

Phosphates are effective only in small concentrations. The mud temperature must be less than 55° C. The salt contamination must be less than 500 ppm sodium chloride. The concentration of calcium ions should be kept... 

Cement accelerators are shown in Table 10-12. The most common accelerators are calcium chloride and sodium chloride. Calcium chloride may be used in concentrations up to 4% by weight in wells with bottom-hole temperatures less than 50° C. Calcium chloride tends to increase the final strength under pressure conditions. 

The quality of the refined metal, and the current efficiency strongly depend on the soluble vanadium in the bath and the quality of the anode feed. As the amount of vanadium in the anode decreases, the current efficiency and the purity of the refined product also decrease. A laboratory preparation of the metal with a purity of better than 99.5%, containing low levels of nitrogen (30-50 ppm) and of oxygen (400-1000 ppm) has been possible. The purity obtainable with potassium chloride-lithium chloride-vanadium dichloride and with sodium chloride-calcium chloride-vanadium dichloride mixtures is better than that obtainable with other molten salt mixtures. The major impurities are iron and chromium. Aluminum also gets dissolved in the melt due to chemical and electrochemical reactions but its concentrations in the electrolyte and in the final product have been found to be quite low. The average current efficiency of the process is about 70%, with a metal recovery of 80 to 85%. 

For acute symptomatic hypocalcemia, 200 to 300 mg of elemental calcium is administered IV and repeated until symptoms are fully controlled. This is achieved by infusing 1 g of calcium chloride or 2 to 3 grams of calcium at a rate no faster than 30 to 60 mg of elemental calcium per minute. More rapid administration is associated with hypotension, bradycardia, or cardiac asystole. Total calcium concentration is commonly monitored in critically ill patients. Under normal circumstances, about half of calcium is loosely bound to serum proteins while the other half is free. Total calcium concentration measures bound and free calcium. Ionized calcium measures free calcium only. Under usual circumstances, a normal calcium level implies a normal free ionized calcium level. Ionized calcium should be obtained in patients with comorbid conditions that would lead to inconsistency between total calcium and free serum calcium (abnormal albumin, protein, or immunoglobulin concentrations). For chronic asymptomatic hypocalcemia, oral calcium supplements are given at doses of 2 to 4 g/day of elemental calcium. Many patients with calcium deficiency have concurrent vitamin D deficiency that must also be corrected in order to restore calcium homeostasis.2,37,38... 

The only fluid, common to oil field operations, that has a significant interaction with TKPP solutions was concentrated calcium chloride. Solutions of calcium chloride, spent acid, are generated during the acidization of a limestone or a dolomite formation. When solutions containing 10% calcium chloride were mixed in equal proportions with 14.5 ppg TKPP solutions, massive precipitation occurred. Similar precipitation was observed with oil field brines having calcium concentrations above 400 ppm. 

Calcium-selective electrodes have long been in use for the estimation of calcium concentrations - early applications included their use in complexometric titrations, especially of calcium in the presence of magnesium (42). Subsequently they have found use in a variety of systems, particularly for determining stability constants. Examples include determinations for ligands such as chloride, nitrate, acetate, and malonate (mal) (43), several diazacrown ethers (44,45), and methyl aldofuranosides (46). Other applications have included the estimation of Ca2+ levels in blood plasma (47) and in human hair (where the results compared satisfactorily with those from neutron activation analysis) (48). Ion-selective electrodes based on carboxylic polyether ionophores are mentioned in Section IV.B below. Though calcium-selective electrodes are convenient they are not particularly sensitive, and have slow response times. 

The particular amphoteric resin that is employed in the BDH process has a high affinity for calcium and magnesium chloride in concentrated sodium chloride brines. In dilute solutions the selectivity is lost, so that regeneration can be effected with a simple water wash. The process was found to be effective over a wide range of hardness and brine concentrations. 

Living cells visualization of membranes, lipids, proteins, DNA, RNA, surface antigens, surface glycoconjugates membrane dynamics membrane permeability membrane potential intracellular pH cytoplasmic calcium, sodium, chloride, proton concentration redox state enzyme activities cell-cell and cell-virus interactions membrane fusion endocytosis viability, cell cycle cytotoxic activity... 

Dissolved Concentrations of Calcium and SO2 Species. The equilibrium dissolved concentrations of total calcium and SO2 (sulfite plus bisulfite) species are important because comparison of these equilibrium concentrations with actual measured values determines the degree of gypsum saturation, and hence the potential for gypsum scale formation in the scrubber. As a first approximation, the fraction gypsum saturation of a scrubber liquor, having specified pH and specified concentrations of magnesium and chloride, is proportional to the measured calcium concentration, and inversely proportional to the measured S02 concentration. 

Figure 5. Dissolved calcium concentration as a function of chloride-to-magnesium ratio for liquors saturated with calcium sulfite and gypsum at pH 5.5 and 50°C...

In this experiment, tap water with added phosphate was used as influent. Concentration of phosphate was adjusted to an adequate range from 2 to 23 mg/jg. Calcium chloride and sodium hydroxide solution were added to maintain calcium concentration from 70 to 100 mg/jg and pH of the effluent from 9.0 to 9.5. Using this equipment, we performed experiments to obtain efficiency of phosphate removal, relationship between phosphate concentration, and crystallization rate and factors affecting phoshate removal. 

Seawater is an example of a liquid solution with water as solvent because the dissolved sodium chloride, calcium carbonate, magnesium bromide, and other solutes are of varying concentrations. Carbonated soda-water is another liquid solution, but in this case, the solute is a gas—carbon dioxide. 

The presence of calcium chloride at concentrations greater than about 1.5% by weight of cement can lead to breakdown of the passive layer of Fe203 normally present at the steel/concrete interface, rendering the... 

Crystalline and amorphous substances that are stable in the air and do not decompose when heated in the temperature interval from 100 to 130 °C are dried in a drying cabinet. The same substances can be dried in the air and in a desiccator over phosphorus anhydride, anhydrous calcium chloride, or concentrated sulphuric acid. 

The most important problem is that of contamination of process solutions. Just to take one example, that of nickel, sodium and calcium concentrations have been shown to increase when dragout is returned to the process solution, likely sources being the water used for rinsing. These contaminants interfere with the plating process. Organics, chlorides, and heavy metals, from sources including the process solution itself and the work being processed, can also accumulate and pose problems. And finally, nickel metal can rise to undesirable concentrations because of the difference in anode and cathode efficiencies. While these problems may take years to manifest themselves in a low-volume operation, eventually treatment and purification is required.[20]... 

Calcium precipitation of whey proteins produces a hydrated coagulum. Schmidt et al. (1979) found hardness of whey protein gels to be greatest when 11.1 mM calcium chloride was added, de Rham and Chanton (1984) observed that calcium concentrations critical for precipitation of whey proteins were independant of the calcium-to-protein ratios. 

The hydrogen atoms of the hydroxyl groups are not involved in the formation of metal complexes. At least one of them can be replaced by a methyl group. Methyl a-D-allopyranoside shows downfield shifts in its NMR spectrum similar to those of a-D-allopyranose on addition of calcium chloride it seems to complex to a similar extent. One feature of this NMR spectrum is that the H-2 triplet, hidden among the other protons in the uncomplexed state, appears at calcium concentrations over 1.5M. This is one of several cases where complex formation reveals details of NMR spectra or improves resolution by separating the signals of protons from each other. 

Using 150 pL of sample, a complete report containing the concentration of ionized magnesium, ionized calcium, sodium, potassium, chloride, pH and recalculated to pH — 7.40, the so-called pH-cor-rected ionized magnesium and calcium concentration can be obtained after a total measurement time of less than 2 min. The lifetime of the Mg-ISE is 2000 blood samples [4]. 

Breuing EP, Kaminskas R, Kobashi YL, et al. 1987. Effects of sodium and calcium concentrations on the barium chloride-induced electrical and contractile responses of the guinea-pig vas deferens. Braz J Med Biol Res 20 231-242. 

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