Terra alba

Weiss-erde, /, white earth, terra alba, specif, white clay, -erz, n. arsenopjo-ite siderite krennerite an impure marcasite. -farbe,/. white color, white pigment,... 

The Latin term terra alba (white earth) is often used indiscriminately to refer to such white minerals as chalk, gypsum, and kaolin. Chalk, also known as... 

Kaolin, China clay, terra alba, argille, porcelain clay, and white bole are the generic names used to refer to primary clays that include three distinct white minerals - kaolinite, nacrite, and dickite - all of which share a very similar composition but differ slightly in their structure. Kaolin is rarely found pure, but as a natural mixture with other varieties of clay together, the various clays make up over 95% of the total weight of the mixture, other earthy... 

In Desert ecosystems similar to Steppe ecosystems the plants distinctly exhibit their biogeochemical specificity. We can consider the distribution of heavy metals in Dry Desert ecosystems of the Ustyurt Plateau, Kazakhstan, with predominance of wormwood (Artemisia terrae albae) and saxaul (Anabasis salsa). In rubble stone territories, of common occurrence is the dense shrubbery of Sasola anbuscula. Most elements found in the wormwood occur in their highest concentrations. In the roots of the wormwood and saxaul, higher contents of Mn, Cu, Mo, and Sr have been monitored, whereas the aerial parts contain more Ti, V, and Zr. We can see that the root elements are most biologically active and those in aerial parts, more inert. Possibly their presence was related to the dust exposure and deposition on the plant exterior (see above). 

Figure 4. Coefficients ofbiogeochemical uptake of trace metals by plant species of the Ustyurt Plateau Dry Desert ecosystems. 1 —wormwood (Artemisia terrae albae), aerial parts 2—roots 3—saxaul (Anabasis salsa), aerial parts and 4—roots (Dobrovolsky, 1994).

Terra alba or dead-burned, fine white gypsum is used as a paper filler, in plastics, and as an exlender far titanium dioxide. Pharmaceutically pure gypsum can be added to bread and other bakery products, finds use in beer production, and as a pharmaceutical-tablet diluent. In Japan, calcium sulfate is used in making tofu, a soyabean curd. 

SYNS ALABASTER ANNAUNE C.I. 77231 C.I. PIGMENT WHITE 25 GYPSUM GYPSUM STONE LAND PLASTER UGHT SPAR MAGNESIA WHITE MINERAL W HITE NATIVE CALCIUM SULFATE PRECIPITATED CALCIUM SULFATE SATINITE SATIN SPAR SULFURIC ACID, CALCIUM(2+) SALT, DIHYDRATE TERRA ALBA... 

Calcium sulfate dihydrate alabaster Cal-Tab-, Compactroh, Destab-, E516 gypsum light spar mineral white native calcium sulfate precipitated calcium sulfate satinite satin spar selenite terra alba USG Terra Alba. 

Particle size distribution 93% less than 45 pm in size for the dihydrate (175G Terra Alba) 97% less than 45 pm in size for the anhydrous material (Snow White). Average particle size is 17 pm for the dihydrate and 8 pm for the anhydrous material. For Compactrol, not less than 98% passes through a 40 screen (425 pm), and not less than 85% is retained in a 140 screen (100 pm). 

A relatively pure form of natural gypsum (Terra Alba) consisting of 98.6% CaSO ZHjO was used for this study. The gypsum was ground to pass a 150-p.m (No. 100) sieve and calcined in a laboratory kettle designed for both continuous and batch operation. In this manner, three 15-kg lots of stucco were prepared by continuous calcination, and three 5-kg lots of stucco were calcined by the batch process. To two lots of the latter, either calcium chloride or surfactants were added. 

Figures 3 through 6 illustrate the effect of aging time on consistency and disintegration, as well as the relationship between consistency and disintegration for continuously calcined Terra Alba. These data show that both consistency and disintegration decrease with time and suggest a linear relationship exists between these properties. Regression analysis of the data yields slopes, intercepts, and correlation coefficients of these curves a.s given in Table 2. Similar data for batch calcined stucco are summarized in Table 3.

There is a slight deviation from a linear behavior at early aging periods. For instance. Fig. 7 shows the particle size distribution for continuously calcined Terra Alba dispersed for 7 s at zero- versus one-day aging. The particle size... 

TABLE 2—Terra Alba continuously calcined consistency disintegration regression data. 

TABLE 4—Terra Alba continuously calcined consistency surface area data. 

Tannin, 330 Tantalum. 104 Tar. 297 Tartar. 140 emetic, 142 Taurine, 215. 280 Technics, 857 Teeth, 149 Tellurium, 70 Terebentbene, 278 Terpine. 278. 281 Terptnol, 281 Terra alba, 148 Teat, biuret, 257, 851 Boettger s, 2 ... 

Extra Super Terra Alba. [Qtatles B. Chrystal] Terra alba. 

Terra Alba. [U.S. Gypsum] Fine gypsum filler. 

Dihydrate, native calcium sulfate precipitated calcium sulfate gypsum alabaster selenite terra alba satinite mineral white satin spar light spar. Lumps or powder, d 2.32. It loses only part of its water at 100-150. Sol in water very slowly sol in glycerol. Practically insol in most organic sol -vents. 

Calcium Sulfate Anhydrous NF 164 [Whittaker, Clark Daniels http //www.wcdinc.com]. Calcium Suflate BC 164 [Whittaker, Clark Daniels http //www.wcdinc.com], CAS-20 -4 [U.S. Gypsum http //www.usg.com], Casul 55 HF [Harcros http //www.harcroschem.com]. Extra Super English Terra Alba [Charles B. Chrystal http //www.cbchrystai.com]... 

Gypsum stone Land plaster Light spar Magnesia white Mineral white Native calcium sulfate Pigment white 25 Precipitated calcium sulfate Terra alba... 

Cleary http //www.clearychemical.com]] LP Filler 1 t[U.S. Gypsum http //www.usg.com]] LP Filler 2 [U.S. Gypsum http //www.usg.com] Terra Alba [Allied Custom Gypsum http //WWW. alliedcustomgypsum. com] Terra Alba 1 [U.S. Gypsum http //www.usg.com]] Terra Alba F P [U.S. Gypsum http //www.usg.com]] Valufil t[l -J- Marshall http //www.rJmarshallco.com]] Valu-Fil [Plastic Filler Sales]... 

Extract of Whole Orange. See Orange (Citrus aurantium dulcis) oil Extract of patchouli. See Patchouli (Pogostemon cablin) extract Extracts (petroleum), heavy paraffinic distillate solvent. See Paraffin distillate Extract of yeast. See Yeast extract Extramalt Dark. See Malt extract Extra Olein. See Oleic acid Extra Super English Terra Alba. See Calcium sulfate... 

Terra Aiba 1, Terra Aiba F P, Terra alba Terra Aiba. See Calcium sulfate dihydrate Terracur P. See Fensulfothion Terra-Dry Freeze Dried Aioe Vera Powd. 100X. See Aloe barbadensis gel Terra japonica. See Black catechu Terramycin hydrochloride. See Oxytetracycline hydrochloride... 

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