Magnesium traces

Industrial production media must also contain sources of potassium, phosphorous and magnesium. Trace elements may also have to be added. The water used for medium preparation will be from the public water supply or other readily available source. The quality of the water is carefully monitored because the presence of certain metal salts, for example, calcium, copper and iron, can have adverse effects on both the growth of the oiganism and the rheological properties of the exopolysaccharides. 

To determine the frequency of occurrence of mercury-containing particles in FDR, promptly collected residue from the discharge of mercury fulminate-primed ammunition was examined. Results are given in Table 22.1. In the first firing a small proportion of the particles also contained one of the following elements cobalt (trace), magnesium (trace), nickel (trace), and phosphorus (minor and trace). 

Uthus EO and Nielsen FH (1990) Effect of vanadium, iodine and their interaction on growth, blood variables, liver trace elements and thyroid status indices in rats. Magnesium Trace Elem 9 219-226. 

Atomic fluorescence has found application in a variety of situations and with quite different substances. Lubricating oils have been analyzed for silver, copper, iron, and magnesium. Trace concentrations of zinc in copper have been determined. Some of the other reported applications are the determination of bismuth in aluminum and calcium, copper, magnesium, manganese, potassium, and zinc in soils. Analytical applications of atomic fluorescence will increase as more attention is given to development of the methods applicable to this technique. 

Other 1.3% Potassium Sultur Sodium Chlorine Magnesium Trace elements... 

Allain, R, Berre, S., Premel-Cabic, A., Mauras.Y, Cledes, A., and Cournot,A. (1991). Urinary elimination of molybdenum by healthy subjects as determined by inductively coupled plasma mass spectrometry. Magnesium Trace Elem. 10(1), 47-50. 

This has been made in trace quantities by the action of dilute hydrochloric acid on magnesium plated with polonium. As expected, it is extremely unstable and decomposes even at 100 K,... 

When the addition of the bromobenzene is complete and the ether is boiling gently, reheat the flask on the water-bath for a further 15 minutes to ensure completion of the reaction the solution will now be slightly dark in colour, and only a trace of metallic magnesium should remain. 

Make a thin paste of 21 5 g. of finely-powdered o-tolidine (a commercial product) with 300 ml. of water in a 1-litre beaker, add 25 g. (21 ml.) of concentrated hydrochloric acid, and warm until dissolved. Cool the solution to 10° with ice, stir mechanically, and add a further 25 g. (21 ml.) of concentrated hydrochloric acid (1) partial separation of o tolidine dihydrochloride will occur. Add a solution of 15 g, of sodium nitrite in 30 ml. of water as rapidly as possible, but keep the temperature below 15° a slight excess of nitrous acid is not harmful in this preparation. Add the clear, orange tetrazonium solution to 175 ml. of 30 per cent, hypophosphorous acid (2), and allow the mixture to stand, loosely stoppered, at room temperature for 16-18 hours. Transfer to a separatory funnel, and remove the upper red oily layer. Extract the aqueous layer with 50 ml, of benzene. Dry the combined upper layer and benzene extract with anhydrous magnesium sulphate, and remove the benzene by distillation (compare Fig. II, 13, 4) from a Widmer or similar flask (Figs. II, 24, 3-5) heat in an oil bath to 150° to ensure the removal of the last traces of benzene. Distil the residue at ca. 3 mm. pressure and a temperature of 155°. Collect the 3 3 -dimethyldiphenyl as a pale yellow liquid at 114-115°/3 mm. raise the bath temperature to about 170° when the temperature of the thermometer in the flask commences to fall. The yield is 14 g. 

Method 2. Ethyl p-nitrobenzoate. Place 21 g. of p-nitrobenzoic acid (Section IV,154), 11-5 g. of absolute ethyl alcohol, 3 8 g. of concentrated sulphuric acid, and 30 ml. of sodium-dried A.R. benzene in a 250 ml. round-bottomed flask, fit a reflux condenser, and heat the mixture under reflux for 16 hours. Add 50 ml. of ether to the cold reaction mixture, wash the extract successively with sodium bicarbonate soiution and water, dry with anhydrous magnesium sulphate or calcium chloride, and distil off the solvent on a water bath. Remove the last traces of benzene either by heating in an open evaporating dish on a water bath or in a bath at 100-110°. The residual ethyl p-nitrobenzoate (21 g.) solidifies completely on cooling and melts at 56°. 

Thirty minutes after refluxing had stopped, a trace of copper(I) bromide was added to terminate the conversion. The reaction mixture was cautiously poured on to 500 g of finely crushed ice, then 200 ml of 4 N hydrochloric acid were added. After the remaining ice had melted the layers were separated and the aqueous layer was extracted three times with diethyl ether. The combined ethereal solutions were washed with saturated NaCl solution and dried over magnesium sulfate. The greater part of... 

A mixture of 0.15 mol of 1-methylthio-1,2-pentadiene (see Chapter IV, Exp. 26), 100 ml of water, 40 ml of methanol (note 1) and 0.18 mol of NalO., was vigorously stirred. The temperature rose gradually, but was kept between 30 and 35°C by occasional cooling. After 1.5 h 500 ml of water were added to the white suspension and ten extractions with 30-ml portions of chloroform were carried out. The extracts were dried (without previous washing) over magnesium sulfate. Evaporation of the solvent in a water-pump vacuum (the last traces at 0.5-1 mmHg) gave the... 

Magnesium titanium alloys form the hydrides Mg2TiHg [74811-18-0] and MgTi2H [58244-88-5] (17). Traces of a third metal are often added to adjust dissociation pressures and/or temperatures to convenient ranges. 

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