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Pressure indirect

For the top of a distillation column, we usually control the pressure indirectly via the... [Pg.101]

Investigation at the Chemical Physics Institute of the Academy of Sciences has shown for large chge diameters of condensed expls, pressures of the order of 3.1C)5kg/cm2 arise in the detonation wave) 223 [Calcn of pressure from Van der Vaals equation of state p=RT/(v-b)] 224 (Assumption of Landau Stanyukovich that in the explosion products of Landau 8t Stanyukovich for a density in excess of 1 g/cm2 the main part of pressure is of elastic origin and depends only on the density of expln products, but not on the temp) 217 (Effect of pressure on thermal dissociation is discussed. In the case of condensed expls the pressure indirectly affects the molecular separation and alters the rate of chemical reaction. Experiments of Yu.N. Riabinin have shown that the reaction rate was diminished at a high pressure, up to 5.10 kg/cm2)... [Pg.485]

For gases the pressure is related only to the number of collisions betw molecules, while the nature or quality of the collisions depends only on the temp and not on the pressure. In the case of condensed expls the pressure indirectly affects the molecular separation and alters the rate of chemical reaction... [Pg.503]

Heat transfer Local velocities, concentration, and pressure Indirect... [Pg.531]

Pc = capillary hydrostatic pressure (indirectly estimated in the clinical setting, e.g., pulmonary artery occlusive pressure)... [Pg.480]

One point to mention is that SFG is not fully independent of the gaseous environment. At pressures above 1 Torr, a significant energy-dependent infrared absorption occurs via vibrational and rotational excitation of gas phase molecules. Since the intensity of the SFG depends on the input infrared beam intensity, gas pressure indirectly influences the outcome of SFG. To compensate for such an effect, several strategies have been proposed. Another point is that the SFG phenomenon depends on both infrared and Raman absorption coefficients and therefore correlation of band intensity with adsorbate concentration is not straightforward. [Pg.153]

Keywords d rec methods, indirect methods, rock properties, coring, core barrel, standard core analysis, special core analysis, slabbed core, sidewall samples, direct indications, microfossils, sonde, logging unit, invasion, mudcake, formation pressure measurement, fluid sampling, measurement while drilling, formation evaluation while drilling. [Pg.125]

Here, r is positive and there is thus an increased vapor pressure. In the case of water, P/ is about 1.001 if r is 10" cm, 1.011 if r is 10" cm, and 1.114 if r is 10 cm or 100 A. The effect has been verified experimentally for several liquids [20], down to radii of the order of 0.1 m, and indirect measurements have verified the Kelvin equation for R values down to about 30 A [19]. The phenomenon provides a ready explanation for the ability of vapors to supersaturate. The formation of a new liquid phase begins with small clusters that may grow or aggregate into droplets. In the absence of dust or other foreign surfaces, there will be an activation energy for the formation of these small clusters corresponding to the increased free energy due to the curvature of the surface (see Section IX-2). [Pg.54]

The use of selectively reduced integration to obtain accurate non-trivial solutions for incompressible flow problems by the continuous penalty method is not robust and failure may occur. An alternative method called the discrete penalty technique was therefore developed. In this technique separate discretizations for the equation of motion and the penalty relationship (3.6) are first obtained and then the pressure in the equation of motion is substituted using these discretized forms. Finite elements used in conjunction with the discrete penalty scheme must provide appropriate interpolation orders for velocity and pressure to satisfy the BB condition. This is in contrast to the continuous penalty method in which the satisfaction of the stability condition is achieved indirectly through... [Pg.76]

Vacuum Treatment. Milk can be exposed to a vacuum to remove low boiling substances, eg, onions, garlic, and some silage, which may impart off-flavors to the milk, particularly the fat portion. A three-stage vacuum unit, known as a vacreator, produces pressures of 17, 51—68, and 88—95 kPa (127, 381—508, and 660—711 mm Hg). A continuous vacuum unit in the HTST system may consist of one or two chambers and be heated by Hve steam, with an equivalent release of water by evaporation, or flash steam to carry off the volatiles. If Hve steam is used, it must be cuUnary steam which is produced by heating potable water with an indirect heat exchanger. Dry saturated steam is desired for food processing operations. [Pg.359]

Ammonia is used in the fibers and plastic industry as the source of nitrogen for the production of caprolactam, the monomer for nylon 6. Oxidation of propylene with ammonia gives acrylonitrile (qv), used for the manufacture of acryHc fibers, resins, and elastomers. Hexamethylenetetramine (HMTA), produced from ammonia and formaldehyde, is used in the manufacture of phenoHc thermosetting resins (see Phenolic resins). Toluene 2,4-cHisocyanate (TDI), employed in the production of polyurethane foam, indirectly consumes ammonia because nitric acid is a raw material in the TDI manufacturing process (see Amines Isocyanates). Urea, which is produced from ammonia, is used in the manufacture of urea—formaldehyde synthetic resins (see Amino resins). Melamine is produced by polymerization of dicyanodiamine and high pressure, high temperature pyrolysis of urea, both in the presence of ammonia (see Cyanamides). [Pg.358]

Vacuum gauges may be broadly classified as either direct or indirect (10). Direct gauges measure pressure as force pet unit area. Indirect gauges measure a physical property, such as thermal conductivity or ionisation potential, known to change in a predictable manner with the molecular density of the gas. [Pg.26]

Process. A typical indirect hydration process is presented in Eigure 1. In the process, propylene reacts with sulfuric acid (>60 wt%) in agitated reactors or absorbers at moderate (0.7—2.8 MPa (100—400 psig)) pressure. The isopropyl sulfate esters form and are maintained in the Hquid state at 20—80°C. Low propylene concentrations, ie, 50 wt %, can be tolerated, but concentrations of 65 wt % or higher are preferred to achieve high alcohol yields. Because the reaction is exothermic, internal cooling coils or external heat exchangers are used to control the temperature. [Pg.107]

Moreover, digitahs has indirect effects on the circulation, which in normal hearts results in a small increase in arterial pressure, peripheral resistance, and cardiac output (114). The effects of digitahs on the circulation of an individual experiencing congestive heart failure are much more dramatic, however. The increased cardiac output, for example, increases renal blood flow which can reheve in part the edema of CHF associated with salt and water retention (114). [Pg.129]

Composite resins can be cured using a variety of methods. Intraoral curing can be done by chemical means, where amine—peroxide initiators are blended in the material to start the free-radical reaction. Visible light in the blue (470—490 nm) spectmm is used to intraoraHy cure systems containing amine—quin one initiators (247). Ultraviolet systems were used in some early materials but are no longer available (248). Laboratory curing of indirect restorations can be done by the above methods as well as the additional appHcation of heat and pressure (249,250). [Pg.493]


See other pages where Pressure indirect is mentioned: [Pg.135]    [Pg.21]    [Pg.26]    [Pg.521]    [Pg.62]    [Pg.255]    [Pg.107]    [Pg.21]    [Pg.40]    [Pg.106]    [Pg.175]    [Pg.115]    [Pg.106]    [Pg.39]    [Pg.135]    [Pg.21]    [Pg.26]    [Pg.521]    [Pg.62]    [Pg.255]    [Pg.107]    [Pg.21]    [Pg.40]    [Pg.106]    [Pg.175]    [Pg.115]    [Pg.106]    [Pg.39]    [Pg.2123]    [Pg.11]    [Pg.502]    [Pg.508]    [Pg.191]    [Pg.513]    [Pg.185]    [Pg.124]    [Pg.351]    [Pg.439]    [Pg.26]    [Pg.28]    [Pg.68]    [Pg.25]    [Pg.119]    [Pg.473]    [Pg.247]    [Pg.307]    [Pg.237]    [Pg.237]    [Pg.241]   
See also in sourсe #XX -- [ Pg.162 ]




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