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Mixtures regular

This energy equation is a mean-field description of all binary regular mixtures regular solutions, polymer solutions, and polymer blends. [Pg.142]

Hydrocarbon mixtures can be assumed to be regular solutions it is thus possible to estimate the activity coefficient using a relation published by Hildebrandt (1950) ... [Pg.153]

If maintenance is performed, there are two principal maintenance strategies preventive and breakdown maintenance. These are not mutually exclusive, and may be combined even in the same piece of equipment. Take for example a private motor car. The owner performs a mixture of preventive maintenance (by adding lubricating oil, topping up the battery fluid, hydraulic fluid and coolant) with breakdown maintenance (e.g. only replacing the starter motor when it fails, rather than at regular intervals). [Pg.288]

Contact angle will vary with liquid composition, often in a regular way as illustrated in Fig. X-13 (see also Ref. 136). Li, Ng, and Neumann have studied the contact angles of binary liquid mixtures on teflon and found that the equation of state that describes... [Pg.370]

The attitude we adopt in this discussion is that only those chain segments in the middle of the chain possess sufficient regularity to crystallize. Hence we picture crystallization occurring from a mixture in which the concentration of crystallizable units is Xj and the concentration of solute or diluent is Xg. The effect of solute on the freezing (melting) point of a solvent is a well-known result T j, is lowered. Standard thermodynamic analysis yields the relationship... [Pg.217]

The flow diagram for the viscose process is given in Figure 2. The sequence of reactions necessary to convert cellulose into its xanthate and dissolve it in soda used to be performed batchwise. Fully continuous processes, or mixtures of batch and continuous process stages, are more appropriate for high volume regular viscose staple production. [Pg.346]

To extend the study of the apparent decomposition recombination reaction, and specifically to determine if the carbon atoms exchange with other atoms in other acetylene molecules, tests using carbon isotopes were conducted. A mixture of 50% regular acetylene, C2H2, and 50% heavy acetylene. [Pg.383]

NPH Isophane Human Insulin Suspension. NPH isophane insulin, also called Humulin N, Insulatard NPH Human, or Novolin N is an intermediate-acting form of human insulin produced by recombinant DNA techniques. Mixtures Humulin 70/30 and Novolin 70/30 contain 70% NPH isophane and 30% regular, whereas Humulin 50/50 contains 50% NPH isophane and 50% regular. It is adrninistered subcutaneously and should not be given intravenously. Absorption is delayed because the insulin is conjugated with protamine in a complex of reduced isoelectric solubiUty. Therapeutically, this preparation is probably comparable to purified porcine NPH insulin. However, human NPH insulin may have a slightly shorter duration of action than comparable purified porcine products. [Pg.340]

The characteristics of a powder that determine its apparent density are rather complex, but some general statements with respect to powder variables and their effect on the density of the loose powder can be made. (/) The smaller the particles, the greater the specific surface area of the powder. This increases the friction between the particles and lowers the apparent density but enhances the rate of sintering. (2) Powders having very irregular-shaped particles are usually characterized by a lower apparent density than more regular or spherical ones. This is shown in Table 4 for three different types of copper powders having identical particle size distribution but different particle shape. These data illustrate the decisive influence of particle shape on apparent density. (J) In any mixture of coarse and fine powder particles, an optimum mixture results in maximum apparent density. This optimum mixture is reached when the fine particles fill the voids between the coarse particles. [Pg.181]

Preparation of Pillared Clay Catalysts. PAG products are used for the preparation of zeolite-like catalysts by intercalation, the insertion of Al polycations molecules between the alurninosiHcate sheets of clay (3,33). Aqueous clay suspensions are slowly added to vigorously stirred PAG solutions, and the reaction mixture is aged for several hours. The clay is separated from the PAG solution and washed free of chloride ion. The treated clay is first dried at low temperature and then calcined in air at 450—500°G, producing a high surface area material having a regular-sized pore opening of about 0.6 to... [Pg.180]

A key feature of this model is that no data for mixtures are required to apply the regular-solution equations because the solubiHty parameters are evaluated from pure-component data. Results based on these equations should be treated as only quaHtative. However, mixtures of nonpolar or slightly polar, nonassociating chemicals, can sometimes be modeled adequately (1,3,18). AppHcations of this model have been limited to hydrocarbons (qv) and a few gases associated with petroleum (qv) and natural gas (see Gas, natural) processiag, such as N2, H2, CO2, and H2S. Values for 5 and H can be found ia many references (1—3,7). [Pg.237]

This model is appropriate for random mixtures of elements in which tire pairwise bonding energies remain constant. In most solutions it is found that these are dependent on composition, leading to departures from regular solution behaviour, and therefore the above equations must be conhned in use to solute concentrations up to about 10 mole per cent. [Pg.354]

The rate of heating controls the rate of evolution of the methyl mercaptan. After the rapid evolution of the gas begins, the reaction mixture should be heated very gentl c A slight suction aids in obtaining a regular flow of the gas. [Pg.55]

Besides the medicinally used herbal mixtures, there arc also the so-called household teas which are preferred by people who are sensitive to coffee or who do not wish to drink a caffeine-containing beverage on a regular basis. Household teas are made up from drugs which, apart from small amounts of tannins, have only aroma substances and possibly also plant acids bramble leaves, raspberry leaves, hibiscus flowers, hips and haws, and apple skins arc frequent components of such teas [4]. [Pg.18]


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See also in sourсe #XX -- [ Pg.99 ]




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