Manganese content

Table 5. World Manganese Resources and Reserves Base, 10 t Manganese Content ...

Total world production of manganese ores in 1992 was about 6.7 x 10 metric tons manganese content, down from 9.3 x 10 in 1989. Table 13 shows the price of a kilogram of manganese in terms of constant U.S. 1987 doUars, ie, adjusted for inflation. 

Lead peroxide analytical reagent of low manganese content was used. 

Gray cast irons do not have the abrupt ductile to brittle fraction transition down to -40°C as takes place in steels. Special austenitic nodular cast iron similar to the AUS 203 grade, but with a higher manganese content of about 4%, has been obtained for cryogenic purposes for temperatures down to -253°C. 

For initial practice in the method determine the manganese content of anhydrous manganese(II) sulphate. Heat manganese(II) sulphate crystals to 280 °C, allow to cool, grind to a fine powder, re-heat at 280 °C for 30 minutes, and allow to cool in a desiccator. Weigh accurately about 2.2 g of the anhydrous manganese(II) sulphate, dissolve it in water and make up to 250 mL in a graduated flask. 

Iron and manganese contents of sphalerite coexisting with stannoidite are in the range from 0.17 to 1.93 wt%, and from 0.02 to 0.16 wt%, respectively. 

Once the thermal runaway had become established, the high temperature could allow a smelting reaction (reduction of lead oxides by carbon to metallic lead) to occur, and the low m.p. and high density (327°C, 10.6, respectively) would cause the molten lead to concentrate at the base of the reactor, decreasing the lead content and raising the manganese content of the bulk of the clinker residue, as was observed [2],... 

Total Mo in soils of Russia varies from 1-20 mg/kg. In the Stavropol region, total Zn is in the range of 14.4-71 mg/kg. In the Rostov regions, total Zn is 680 mg/kg. Manganese content varies from 600-1000 mg/kg. Saline soils have low concentrations of total Co. In saline soils, total Cu varies from 60-64 mg/kg and in the very saline alkali soils, Cu is 164 mg/kg. 

Shuman L.M., Wang J. Effect of rice variety on zinc, cadmium, iron and manganese content in rhizosphere and non-rhizosphere soils fractions. Commun. Soil Sci Plant Anal 1997 28 23-36. 

An increase in the manganese content into the 36 to 43 a/o range results in the appearance of a new reflection corresponding to a d value of 0.172 nm (29 = 53.2°) and the disappearance of the 600 reflection of the /-brass structure (Figure 28(b)). Strong 330 and 633 reflections remain. These changes in the diffraction pattern reflect... 

The theoretical yield of the method is less than 100%, as only 80 - 90% of the aqueous phase is removed after back-extraction. The actual yield obtained by 54 Mn counting was 69.5 7.8%, and this can be allowed for in the calculation of results. Environmental Protection Agency standard seawater samples of known manganese content (4370 ng/1) gave good manganese recoveries (4260 ng/1). 

The LiNii-yMnjD2 phase system was studied by the Dahn group in 1992. They reported a solid solution for y < 0.5 but a deterioration of the electrochemical behavior with increasing manganese content. Spahr... 

Calcium and particularly magnesium show excessive vapor pressure at steelmaking temperatures. Table I, but this alloyability problem has been somewhat alleviated bj - submerging the introduction of the calcium alloy under 3 meters of liquid steel (31) However, independently of vapor pressure, it is the low solubility of calcium in liquid iron which limits the effective substitution of >feiS by CaS to extremely low sulfur levels, particiilarly when the manganese content is high, 2% for example (32). 

The range of potato manganese content has been reported from 0.73-3. 62 p,g/g FW (Rivero etal., 2003) to 9-13 p,g/g DW (Orphanos, 1980). Manganese has a role in blood sugar regulation, metabolism, and thyroid hormone function. Recommended daily intake in the USA is 2-10 mg. 

Contamination is a problem one always faces in trace analysis. Mercury is ubiquitous in many laboratories, as is fluoride. Lead is present in dust, particularly in laboratories located close to heavy automobile traffic. Extreme caution must always be exercised as contamination on the trace level may come from unexpected sources. Table I shows that using manganese steel in the jaws used to crush the coal increased the manganese content of the crushed coal more than twofold. 

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