Paste producing

Production of carbon electrodes is a capital-intensive business. Two suppHers dominate the prebaked market. Carbon paste producers are more numerous and tend to serve local markets. There is no international standard for the threaded joints on carbon electrodes. Manufacturers of straight pin carbon electrodes have followed the physical specifications adopted for graphite electrodes (37). Unified standards do not exist for pinless joints resulting in limited interchangeability among brands. Electrode diameters are offered in both English and metric sizes with no restrictions on new or unique diameters. 

In preparing akara from each milled product, too many large particles still remained in the 2 mm material to make a smooth paste. However, highly acceptable akara with uniform shape was produced from this material after the paste was ground to eliminate the large particles. With the 0.5 mm screen, the paste was very fluid and extremely difficult to dispense, behavior which closely resembled that exhibited by the commercial cowpea flour. Akara prepared from the 0.5 mm material was also extremely distorted. Of the three screen sizes compared, the 1.0 mm screen produced the most desirable particle size distribution although the paste produced from the 1.0 mm material was somewhat more fluid than desired, it appeared that adjustments could be made in hydration of the meal to achieve an appropriate batter viscosity. 

In order to obtain the free semicarbazide, 5-5 g. of the hydrochloride are ground in a small mortar with 4-5 g. of anhydrous sodium acetate (see p. 127). The paste produced by the formation of free acetic acid is transferred with a spatula to a 100 c.c. conical flask the last portions are washed in with absolute alcohol and the contents of the flask are then boiled on the water bath with (altogether) 50 c.c. of absolute alcohol. During the boiling the flask is frequently... 

Carbon dioxide dissolves in the pore solution of cement paste, producing CO3", which reacts with Ca to produce CaCOj. The OH and Ca ions required by these reactions are obtained by the dissolution of CH and decomposition of the hydrated silicate and aluminate phases. C4AH. is quickly converted into C ACH, and ultimately into CaCOj and hydrous alumina monosulphate and ettringite yield CaCOj, hydrous alumina and gypsum. C-S-H is decalcified, initially by lowering of its Ca/Si ratio, and ultimately by conversion into a highly porous, hydrous form of silica. The... 

With growing environmental concerns, the disposal of small quantities of acid gas is a problem. In the past, producers could flare these acid gases however, in many jurisdictions this is no longer... 

Metal-free phthalocyanine has been prepared in several forms a (tetragonal), P (monoclinic), x (hexagonal), and x. Figure 7 shows the interconversions. For example, treatment of Monolite Fast Blue GS (ICI) with hot dimethylformamide followed by ball milling in isopropyl alcohol yields the fi-form as needles, whereas acid pasting produces the a-form as needles and flakes (Loutfy, 1981). Milling under different conditions yields either the x-form as needles or flakes (Takano et al., 1984 Kakuta et al., 1985) or the x-form as needles (Sharp and Lardon, 1968 Hackett, 1971). The x-form as rods has been... 

Cocaine is manufactured by heating a paste produced from the leaves of the coca bush with hydrochloric acid. The resulting white powder is often separated into fine lines and inhaled or snorted into the nose. 

Table VII shows tensile development at 150° and 180°C for Solvesso 150 and Varsol 2. Pastes produced with MIBK as diluent were too viscous even at the early stages to make up films for this particular study.

Classification.—Commercial starches are classified, according to the viscosity of the paste produced, as thick- or thin-boiling. Wheat starch is a typical thin-boiling starch, as a 5% mixture of wheat starch in water yields a thin, translucent syrup, scarcely gelatinous at boiling temperature. Corn starch, on the other hand, is a characteristic thick-boiling starch. Its 5% mixture with boiling water is practically non-fluid. 

Fig. 3.22. Scanning electron micrographs of cured paste produced from 3BS particles. Chaotically interconnected 3BS crystals form a porous mass.

Adhesives (a term generally synonymous with glues, mastics, mucilages, and pastes) produce relatively permanent surface bonds between two substances (paper, glass, wood, metal, etc.) that develop by chemical reaction or as the adhesive cools or dries. The enormous variety of adhesives limits any system of nomenclature, but classification by binder, the major active ingredient, yields the following ... 

A comparison between Figs. 6.6 and 6.8a shows that BaS04 alone exerts no effect on the phase composition of the paste. When 1 % of SL expander is also added, formation of orthorhomb-PbO is suppressed. On comparing Figs. 6.8a and 6.8b, it can be seen that pastes produced with 2% H2SO4 vs. LO tend to contain more 3BS crystals when SL is also added, but on increasing the H2SO4 content in the paste, formation of 3BS crystals does... 

So Much So Past Produced, written, and directed by Steven Ascher and Jeanne Jordan edited by Jeanne Jordan. 

Fig.3 shows the adiabatic temperature versus time for all the studied samples. The addition of clay to the cement paste produces a diminution of the induction period and an increase on the maximum of temperature. Clay accelerates the hydration ratio because it acts as nucleating agent of the CH crystallization. 

Fig. 3.20 C-S-H honeycomb constitution in the pastes produced from the ground granulated blastfurnace slag activated with NUjSiOj, the cracked slag grain is visible. (By the courtesy of B. Trybalska)...

Fig. 6.8 Hadley s grain in the paste produced at w/c = 0.5, 7 days of hydration. (Photo of B. Trybalska)...

Fig. 7.23 Na and Cl apparent diffusion coefBcients in the pastes produced from cement with siliceous fly ash (temperature of 45°C, w/c = 0.40) (according to [139])...

In another approach a cement paste produced with a normal water/cement ratio is exposed to uniaxial pressure after the paste has achieved its initial set. In this way a portion of the mixing water is removed, and the water/solid ratio may be reduced to about 0.1. The residual water allows a continuation of the hydration process, in which a very low-porosity, high-strength material, called pore-reduced cement (PRC), is produced (Macphee, 1990 Macphee et al., 1992 Geslin, 1995). Compressive and tensile strength improvements of up to three and six times respectively may be achieved by this approach. 

In pastes produced with an addition of metakaolin a gradual decomposition of the C-S-H and C AHjj phases occurs, if exposed to elevated temperatures. Nevertheless, a moderate increase of compressive strength of samples heated to temperatures between about 200°C and 500°C may be observed, and this increase may be attributed to the additional hydration of non-hydrated clinker still present in the paste and to an additional... 

When starch is dextrinized by the addition of a-amylase, the resultant paste produces stronger granules with better flowability that produce tablets with shorter disintegration time, lower friability, and less variability in weight and hardness. 

Table n shows the chemical composition of tomato paste produced by the cold break (CB) and the hot break (HB) process as wdl as the composition of tomato flakes produced from CB- and HB-tomato pastes. 

Mush - The paste produced by co-coagulation in the DU Bearing Process is called mush. See also DU Bearing Process. 

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