PIT method

The Utah deposit is located in southwestern Utah near Cedar City. The iron ore deposits are of contact metamorphic origin. The cmde ore contains 35 to 65% iron, primarily in the form of magnetite and goethite. Mining is done by the open pit method. The cmde ore is cmshed, screened at —75 mm (—200 mesh size) and shipped as lump ore containing 54% iron. The ore is rescreened at the steel mill to produce lump ore (10—64 mm) for the blast furnace and sinter feed (0—10 mm) for the sinter plant. 

Flake Mica. Flake mica is mined from weathered and hard rock pegmatites, granodiorite, and schist and gneiss by conventional open-pit methods. In soft, residual material, dozers, shovels, scrapers, and front-end loaders are used to mine the ore. Often kaolin, quartz, and feldspar are recovered along with the mica (see also Clays Silicon compounds). 

The phase inversion temperature (PIT) method is helpful when ethoxylated nonionic surfactants are used to obtain an oil-and-water emulsion. Heating the emulsion inverts it to a water-and-oil emulsion at a critical temperature. When the droplet size and interfacial tension reach a minimum, and upon cooling while stirring, it turns to a stable oil-and-water microemulsion form. " ... 

Shinoda, K. and Saito, H. (1969) Thestability of O/W type emulsions as functions of temperature and the HLB of emulsifiers the emulsification by PIT-method. Journal of Colloid and Interface Science, 30, 258-263. 

Izquierdo, P., Feng, J., Esquena, J.,Tadros, T.F., Dederen, J.C., Garcia, M.J., Azemar, N. and Solans, C. (2005) The influence of surfactant mixing ratio on nano-emulsion formation by the PIT method. Journal of Colloid and Interface Science, 285 (1), 388-394. 

The test pit method consists of excavating a pit using a backhoe to a depth where hydrocarbon pools in the bottom of the pit. Soil samples are subsequently obtained above and below the hydrocarbon-affected zone using hand-driven tubes (acrylic small-diameter shelby tubes). Problems associated with this method include ... 

Emulsification of Very Concentrated Emulsions Using the PIT Method... 

Open Pit "Panel Pit Methods, "Low Panel "High Panel Tests and "Silhouette Test in Vol 3, pp C345 to C350-R. 

In the early 1990s a new copper extraction technology, known as in situ leach mining, was under investigation. This methodology was proposed, and demonstration plants were lo be constructed to test the proposal. These were jointly sponsored projects by the U.S. Bureau of Mines and two mining companies. If successful, leaching would cut ihe costs and hazards of the traditional open-pit methods currently used. 

Mining. Most diatomite is mined by open pit methods. 

Very finely divided emulsions can be prepared by increasing the temperature of the system, forcing an O/W emulsion to invert to a fine W/O emulsion, then cooling the system, causing re-inversion with the formation of very small dispersed oil drops [214]. This method is termed the PIT method. 

Cables via the powder-in-tube (PIT) method The approach is especially suited to processing Bi-2223 into leads and cables for power applications. A silver or silver alloy tube, filled with the partially reacted precursor powders formulated to yield Bi-2223, is drawn down to a wire 1-2mm diameter. The wire is rolled into a tape if that is the required form, usually with a width-to-thickness ratio of approximately 10 1. The composite is then heated to 800-900 °C when the powder partially melts. The recrystallization process is controlled and the pure Bi-2223 phase develops with large grains oriented so that the Cu-O planes lie parallel to the silver surface to optimize Jc. 

Bi-2212 tapes were made by the PIT method . Appropriate amounts of Bi203, SrCOs, CaCOs, and CuO were thoroughly mixed and calcined in three steps in the... 

Described below are the-three main methods of determining orientation back-reflection Laue, transmission Laue, and diffractometer. Nor should the old etch-pit method be overlooked. This is an optical method, involving the reflection of visible light from the flat sides, of known Miller indices, of etch pits in crystal surfaces. Although not universally applicable, this method is fast and requires only simple apparatus [G.25]. 

In all cases, there was an increase in nanoemulsion radius with increase in the R(0/S). However, when using the high-pressure homogeniser the droplet size could be maintained at values below 100 nm at high R(0/S) values. With the PIT method, there was a rapid increase in r with increase in R 0/S) when the latter... 

As expected, the nanoemulsions prepared using high-pressure homogenisation showed a lower Ostwald ripening rate when compared to systems prepared using the PIT method. This is illustrated in Figure 14.18, which shows plots of versus... 

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