Ground carbonation

Calcium carbonate, available both from natural sources and as precipitated forms (see Calcium compounds), is most useful in coating because of purity and high brightness, ie, 90—95%. Ground carbonates from marble deposits have high purity levels as do the carbonates from some chalk deposits. 

G. Johansson, Below-ground carbon distribution in barley Hordeum vulgare L.) with and without nitrogen fertilization. Plant Soil 144 95 (1992). 

Loiseau P, Soussana JF (1999) Elevated [C02], temperature increase and N supply effects on the turnover of below-ground carbon in a temperate grassland ecosystem. Plant Soil 210 233-247... 

The carbon paste electrode is suitable for aqueous solutions and is prepared by mixing finely ground carbon with mineral oil (in a typical preparation, 15 g of ground carbon is mixed with 9 ml of Nujol). A paste of butter-like consistency is obtained that can be shaped into small disks. 

Powdered activated carbon (PAC) PAC is made up of crashed or ground carbon particles, 95-100% of which will pass through a designated sieve—0.297 mm according to the American Water Works Association Standard, or 0.177 mm according to ASTM D5158. PAC is mainly used for biological treatment. 

Thermal analysis was carried out using TA Instrument Thermal Analyzer. The instrument settings were heating rate 10 K/min and a nitrogen atmosphere with 100 mL/min flow rate. For each measurement about 25 mg of a ground carbon sample were used. 

FIGURE 1 The relationship between above ground carbon density and above ground phosphorus density for moist tropical forests growing on moderately fertile ( ) and infertile(B) soils. 

As an indication of the flexibility of the EAF, it is used in some developing countries for the direct reduction of iron ore by carbon [27.18]. The furnace is charged with iron ore intimately mixed with ground carbon. Quicklime, calcined dolomite and fluorspar are added and an oxygen lance is used to oxidise the impurities much as in the BOS process. The slag is removed and the chemical... 

All crops add carbon to a soil in the form of root residues even though essentially all of the above-ground portions may be removed. This added carbon may constitute as little as about 5% of the total crop carbon in the case of some vegetable crops, and as much as perhaps 40% in some of the deep-rooted perennial crops. The above-ground carbon that is returned to the soil may be near zero for many crops and perhaps 50 to near 100% for others, depending on the kind of crop and the disposition made of it. 

The branches and leaves of woody plants that are formed some distance above the ground, carbon-based resources... 

The carbon fiber mat, either alone or supplemented with a ground carbon or graphite filler, provides in-depth grounding systems and static control in hazardous areas where static sparks may result in fires or explosions. 

Self-baking anodes (known as Soderberg anodes), usually one per cell and therefore of much larger dimensions. Such anodes are fed at the top with the ground carbon and pitch binder and this bakes in situ as it gradually descends into the molten electrolyte to form a hard, dense material which acts as the anode surface. 

Ultrasonically devulcanized and ground-carbon black (CB)-filled NR was blended with virgin CB-fiUed material. Figure 11 gives the tensile strength of these NR-NR blends containing 35phr CB [137]. The blends of devulcanized... 

The inventory in the terrestrial biosphere for the present day is summarized in Table II. Because of the heterogeneity of the landscape and the sparsity of measurements, the values in Table II are necessarily estimates. In general, above-ground carbon density is greatest in tropical rain forest where the temperature and abundant precipitation favor NPR By contrast, soil carbon is highest in the tundra where decomposition rates are slow. 

A fine ground carbonate slurry for use in coatings systems where ultrafine particle size is not required. 

Water Purification Solution - 68 20 - - E G water purification solution. 1000 grams ground carbon. 2.5 gal. water (2.5% HCI)... 

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