Brown compact

Electrum occurs mainly in the black ore zone dominantly composed of sphalerite, bornite, galena and barite. It is common in B sub-type such as the Ezuri and Fukazawa deposits. It occurs in brown compact black ore consisting of barite, galena. 

The brown compacts are now sintered, the name given to the heating process in which... 

Debinding is carried out in furnaces suitable for the binder system. The binder may be removed by way of catalysis, dissolving or thermal decomposition. Debinding ean be effectively achieved by a suitable furnace temperature and atmosphere. Removing the binder transforms the moulded part into a porous and sensitive moulded body, referred to as a brown compact . In this condition, the part is only kept stable by minimum binder residues and weak van der Waals forees. 

Tempeh. DehuUed cooked soybeans are inoculated with the mold, Thi pus oligosporus packed in perforated plastic bags, and allowed to ferment for 18 h. The mold mycelium overgrows the soybean cotyledons and forms a compact cake. When sHced and deep-fried in oil, a crisp and golden brown product is obtained. Although native to Indonesia, tempeh has become popular with vegetarians in the United States and other Western countries (93). 

Compaction Rate Processes The performance of compac tion techniques is controlled by the ability of the particulate phase to uniformly transmit stress and the relationship between apphed stress and the compaction and strength characteristics of the final compacted particulate phase. The general area of study relating compac tion and stress transmission is referred to as powder mechanics (Brown Richards, Principles of Powder Mechanics, Pergamon Press Ltd., Oxford, 1970). 

In a 500-ml., three-necked, round-bottomed flask fitted with a mechanical stirrer and a thermometer is placed 42 g. (1.05 mole) of sodium hydroxide dissolved in 168 ml. of water. The contents of the flask are cooled to —20° and stirred vigorously as 48 g. (0.30 mole) of pyridinium-1-sulfonate (Note 1), which has been previously chilled to — 20°, is added in one portion. The mixture is stirred for 20 minutes while the temperature is kept below —5° (Note 2). The cooling bath is removed, and the mixture is stirred and warmed gradually to 20° over 20 minutes. The temperature of the dark orange mixture is then raised to 55-60° and after 1 hour is lowered again to —5°. The brown crystals that separate are filtered by suction, pressed into a compact filter cake, and washed with three 100-ml. portions of acetone (Note 3). The yield of this crude product amounts to 46-52 g. after drying on filter paper overnight or at 50° (1 mm.) for 1 hour. (Note 4). 

Brown SJ, Raja AA, Lewis DFV. A comparison between COMPACT and Hazardexpert evaluations for 80 chemicals tested by the NTP/NCI rodent bioassay. ATLA 1994 22 482-500. 

S—S—) appears to have some specific compact structure, but also gives evidence of structural softness (Epand, 1972a,b). The N-terminal tridecapeptide of RNase A appears to contain only a few percent o-helix (Brown and Klee, 1971). From this very small collection of linear peptides, it appears that the lower size limit for a stable compact structure is in the range of 20 and 40 residues. This agrees with estimates that can be made from consideration of surface/volume ratios as a function of peptide size (Rose and Wetlaufer, 1977). 

B. Agate, B. Stormont, A.J. Kemp, C.T.A. Brown, U. Keller, and W. Sibbett, Simplified cavity designs for efficient and compact femtosecond Cr LiSAF lasers. Optics Communications 205,207-213 (2002). 

W. Sibbett, B. Agate, C.T.A. Brown, A.A. Lagatsky, C.G. Lebum, B. Stormont, and E.U. Rafailov, Compact Femtosecond Oscillators (invited), in Ultrafast Optics IV, edited by F. Krausz, (Springer Verlag 2004) pp. 3-21. 

To everyone s surprise, no event lasting less than two weeks has ever been observed. The mean mass inferred is half the solar mass, which rules out brown and red dwarfs but favours white dwarfs. However, too many of these remnants from intermediate-mass stars (1-8 Mq at birth) would contradict the traditional tenets of astrophysics. Indeed, it would imply a frenzied spate of nucleosynthesis during the formation of the galactic halo. The nature of the compact massive objects thus remains a mystery. 

Volkmann made three kinds of powder, one yellow in color in which no solvent was used a second, brown in color, which received a solvent treatment of a few minutes only and was only superficially gelatinized and a third, also brown, which was made compact and of any shape by longer treatment with ether-alcohol and molding... 

Carbonate of lead—sparry lead ore—is remarkable for its transparency and lustre when in its purity. Several varieties of this ore are known. It is fouud in the form of ncicular crystals, in compact masses, and often presenting a fibrous, lamellar, and earthy appearance. They all, with the exception of the earthy species, possess a peculiar lustre, like that of whita lead. Earthy carbonate of lead presente several shades of color— brown, green, or blue—dependent upon the nature of the metal associated with it. The mineral is veiy brittle, and its fracture has a waved eonclioidal ap-pearanoe. Its specific gravity varies from 6 to 6 7. 

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