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Heat effects

In order to minimize the probe heating effect (measure disturber), the number of the measure points will be 80x80 (the sweeping time negatively influences the probes ), for example ... [Pg.295]

At the outset it will be profitable to deal with an ideal solution possessing the following properties (i) there is no heat effect when the components are mixed (ii) there is no change in volume when the solution is formed from its components (iii) the vapour pressure of each component is equal to the vapour pressure of the pure substances multiplied by its mol fraction in the solution. The last-named property is merely an expression of Raoult s law, the vapour pressure of a substance is pro-... [Pg.5]

Note 2. Because ethane escaped from the solution, the net heat effect was not very strong. [Pg.57]

For large deformations or for networks with strong interactions—say, hydrogen bonds instead of London forces—the condition for an ideal elastomer may not be satisfied. There is certainly a heat effect associated with crystallization, so (3H/9L) t. would not apply if stretching induced crystal formation. The compounds and conditions we described in the last section correspond to the kind of system for which ideality is a reasonable approximation. [Pg.143]

Genera.1 Ca.se, The simple adiabatic model just discussed often represents an oversimplification, since the real situation implies a multitude of heat effects (/) The heat of solution tends to increase the temperature and thus to reduce the solubihty. 2) In the case of a volatile solvent, partial solvent evaporation absorbs some of the heat. (This effect is particularly important when using water, the cheapest solvent.) (J) Heat is transferred from the hquid to the gas phase and vice versa. (4) Heat is transferred from both phase streams to the shell of the column and from the shell to the outside or to cooling cods. [Pg.29]

This high degree of association results in highly nonideal physical properties. For example, heat effects resulting from vapor association may be significantly larger than the latent heat of vaporization (Fig. 9). Vapor heats of association J for HF to (HF) per mole of (HF) are as follows. To... [Pg.194]

Coke gasification occurs just outside the raceway area where gaseous oxygen is no longer available to completely combust the CO to CO2. This reaction goes essentially to completion at temperatures between 1500 to 2100°C. The net heat effect is exothermic, as shown in equation 1. The endothermic equation (eq. 2) allows control of the temperature in front of the tuyeres by controlling the moisture in the hot blast. [Pg.415]

Other Continuous Processes. Various pasteurization heat treatments ate identified by names such as quick time, vacuum treatment (vacreator), modified tubular (Roswell), small-diameter tube (MaHotizer), and steam injection. The last three methods are ultrahigh temperature (UHT) processes (see Fig. 3). Higher treatment temperatures with shorter times, approaching two seconds, are preferred because the product has to be cooled quickly to prevent deleterious heat effects. [Pg.359]

Dmm-dried products ate more affected by heat than spray-dried products. Drying ia a vacuum chamber decreases the temperature and thus the heat effect on the product, although the atmospheric dryers are used more widely. [Pg.366]

In spite of the higher energy requirements, the spray dryer has gained ia popularity because of the reduced heat effect oa the product as compared to the dmm dryer. Modifications such as foam sprayiag ate being developed to reduce the heat effect further. [Pg.366]

Turbulence. Turbulence is important to achieve efficient mixing of the waste, oxygen, and heat. Effective turbulence is achieved by Hquid atomization (in Hquid injection incinerators), soHds agitation, gas velocity, physical configuration of the reactor interior (baffles, mixing chambers), and cyclonic flow (by design and location of waste and fuel burners). [Pg.168]

Equation 32 represents the upper (or rectifying) operating line equation and equation 33 represents the lower (or stripping) operating line equation. The slopes L jV and L jV can vary, depending on heat effects. [Pg.161]

The heating effect is the limiting factor for all electrophoretic separations. When heat is dissipated rapidly, as in capillary electrophoresis, rapid, high resolution separations are possible. For electrophoretic separations the higher the separating driving force, ie, the electric field strength, the better the resolution. This means that if a way to separate faster can be found, it should also be a more effective separation. This is the opposite of most other separation techniques. [Pg.179]

Capillary Electrophoresis. Capillaries were first appHed as a support medium for electrophoresis in the early 1980s (44,45). The glass capillaries used are typically 20 to 200 p.m in diameter (46), may be filled with buffer or gel, and are frequendy coated on the inside. Capillaries are used because of the high surface-to-volume ratio which allows high voltages without heating effects. The only limitations associated with capillaries are limits of detection and clearance of sample components. [Pg.183]

The standard Gibbs-energy change of reaction AG° is used in the calculation of equilibrium compositions. The standard heat of reaclion AH° is used in the calculation of the heat effects of chemical reaction, and the standard heat-capacity change of reaction is used for extrapolating AH° and AG° with T. Numerical values for AH° and AG° are computed from tabulated formation data, and AC° is determined from empirical expressions for the T dependence of the C° (see, e.g., Eq. [4-142]). [Pg.542]

A useful classification of lands of reaclors is in terms of their concentration distributions. The concentration profiles of certain limiting cases are illustrated in Fig. 7-3 namely, of batch reactors, continuously stirred tanks, and tubular flow reactors. Basic types of flow reactors are illustrated in Fig. 7-4. Many others, employing granular catalysts and for multiphase reactions, are illustratea throughout Sec. 23. The present material deals with the sizes, performances and heat effects of these ideal types. They afford standards of comparison. [Pg.695]


See other pages where Heat effects is mentioned: [Pg.115]    [Pg.84]    [Pg.236]    [Pg.411]    [Pg.1473]    [Pg.1911]    [Pg.1918]    [Pg.2826]    [Pg.90]    [Pg.91]    [Pg.94]    [Pg.113]    [Pg.19]    [Pg.29]    [Pg.29]    [Pg.30]    [Pg.31]    [Pg.461]    [Pg.307]    [Pg.212]    [Pg.366]    [Pg.97]    [Pg.98]    [Pg.64]    [Pg.180]    [Pg.203]    [Pg.95]    [Pg.501]    [Pg.504]    [Pg.170]    [Pg.162]    [Pg.256]    [Pg.638]    [Pg.681]    [Pg.701]   
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See also in sourсe #XX -- [ Pg.1038 ]

See also in sourсe #XX -- [ Pg.261 ]

See also in sourсe #XX -- [ Pg.24 ]

See also in sourсe #XX -- [ Pg.237 ]

See also in sourсe #XX -- [ Pg.281 ]

See also in sourсe #XX -- [ Pg.207 ]




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