CAC

Kipp s apparatus Equipment for the production of a gas by interaction of a liquid and a solid. It consists of three receptacles, the top is reservoir for the liquid and is connected to the bottom. The middle contains the solid and a tap for the gas. When gas is released the liquid rises and reacts with the solid, when the tap is closed the back pressure returns the liquid lo the lower reservoir and reaction cease . Once widely used for the production of H.S (HCl and FeS) and C O (HCl and CaC(3,<). 

F. Perez Quintidn, M.A. Rebollo - Lab. de Aplicaciones Opticas. N. G. Gaggioli - ENDE, CAC, CNEA. Argentine. 

Additives, whether hydrophobic solutes, other surfactants or polymers, tend to nucleate micelles at concentrations lower than in the absence of additive. Due to this nucleating effect of polymers on micellization there is often a measurable erne, usually called a critical aggregation concentration or cac, below the regular erne observed in the absence of added polymer. This cac is usually independent of polymer concentration. The size of these aggregates is usually smaller than that of free micelles, and this size tends to be small even in the presence of added salt (conditions where free micelles tend to grow in size). 

In 0.1 M NaCl both molecular weight samples of PEO depress the cac, to about 1 mM (relative to 1.4 mM in the absence of polymer), but the relative depression is much less than in the absence of salt. 

Rest lain Is can facilitalc (Jo eking a snhslralc in oiccii Ic Lo a birulm g sue. Reslralnts can also facilitate the interaction of two molecules in solution. In both cases, it is nn likely that two dilTereii I n eutral niolccti Ics won Id come into van dcr Waals con tact with cacli other without the use of restraints. 

Chlorine adds to ketene to form chloroacetyl chloride [79-04-9] (78). Chloroacetyl chloride (CAC) is used in large volume in the manufacture of the pre-emergence herbicides alachlor [15972-60-8] and butachlor [23184-66-9]. It is estimated that the CAC requirement for this appHcation was in excess of 45,000 metric tons in 1992. Significant volumes of CAC are also used in pharmaceutical manufacture, such as anesthetics of the Hdocaine type, and in the production of the tear gas chloroacetophenone [532-27-4]. Other commercial methods for the manufacture of CAC have been described (79). 

Calcined alumina markets consume slightly less than 50% of the specialty alumina chemicals production (1—8,20,22—115). Worldwide usage is estimated to be about 50% for refractories (qv), 20% for abrasives, and 25% for ceramics (qv). Calcined aluminas are also used in the manufacture of tabular alumina and calcium aluminate cements (CAC). Quantities are estimated to be over 200,000 and 100,000 t, respectively (7). 

Refined calcined alumina is commonly used in combination with high purity limestone [1317-65-3] to produce high purity calcium aluminate cement (CAC). The manufacture, properties, and appHcations of CAC from bauxite limestone, as weU as high purity CAC, has been described (104). High purity CAC sinters readily in gas-fired rotary kiln calcinations at 1600 —1700 K. CAC reactions are considered practically complete when content of free CaO is less than 0.15% andloss on ignition is less than 0.5% at 1373 K. 

Table 3 Hsts the characteristics of CAC mineral constituents that can occur in CAC of varying purities. The primary hydraulic setting cement phase in all CAC grades is CA [12042-68-1/, CaO AI2O2 the main secondary phase in 70% AI2O2 CAC is Ca2, [12004-88-5] CaO 2AI2O2. CA2 and C 2 ...

CaO 7AI2O2, occur in minor amounts in the 80% AI2O2 CAC products. The phase reacts rapidly with water to initiate hydraulic... 

Table 3. Characteristics of Calcium Aluminate Cement (CAC) Mineral Constituents ...

High purity CA cements are primarily used as binders for high strength refractory castables to form linings up to about 1.0 m thick, as, for example, in iron blast furnaces. Since the 1970s, large monolithic precast CAC castable shapes have found increased usage in a variety of specialty fired shapes that are too expensive to be inventoried. 

Fig. 3. Biosynthetic pathways for amino acids. HMP = hexose monophosphate pathway CAC = citric acid cycle P = phosphate PP = pyrophosphate ...

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