Relative pressure

In Equation (15), the third term is much more important than the second term. The third term gives the enthalpy of the ideal liquid mixture (corrected to zero pressure) relative to that of the ideal vapor at the same temperature and composition. The second term gives the excess enthalpy, i.e. the liquid-phase enthalpy of mixing often little basis exists for evaluation of this term, but fortunately its contribution to total liquid enthalpy is usually not large. [Pg.86]

The four vertical lines on the diagram show the isothermal depletion loci for the main types of hydrocarbon gas (incorporating dry gas and wet gas), gas condensate, volatile oil and black oil. The starting point, or initial conditions of temperature and pressure, relative to the two-phase envelope are different for each fluid type. [Pg.102]

Amount of benzene adsorbed at 20 C on carbon black and on active carbons at low pressures, relative to the amount adsorbed at p/p = 0-175... [Pg.204]

Insoluble Ammonium Polyphosphate. When ammonium phosphates are heated ia the presence of urea (qv), or by themselves under ammonia pressure, relatively water-iasoluble ammonium polyphosphate [68333-79-9] is produced (49). There are several crystal forms and the commercial products, avaUable from Monsanto, Albright WUson, or Hoechst-Celanese, differ ia molecular weight, particle size, solubUity, and surface coating. Insoluble ammonium polyphosphate consists of long chains of repeating 0P(0)(0NH units. [Pg.476]

FIG. 20-71 Classification of agglomeration processes by agitation intensity and compaction pressure. Relative density is with respect to primary particle density and equals (1 — e) where e is the solid volume fraction. Reprinted from Granulation and Coating Technologies for High-Value-Added Industties, Ennis and Litster (1996) with permission of E G Associates. All rights reserved. [Pg.1884]

Even when the building as a whole is maintained under positive pressure, there is always some location (for example, the outdoor air intake) that is under negative pressure relative to the outdoors. Entry of contaminants may be intermittent, occurring only when the wind blows from the direction of the pollutant source. The interaction between pollutant pathways and intermittent or variable driving forces can lead to a single source causing lAQ complaints in areas of the building that are distant from each other and from the source. [Pg.195]

Liquid resins are usually reinforced with fibers (glass, asbestos), because of their brittleness. They are almost always used for process plant construction. As liquid resins they can be catalyzed to cure at room temperature and low pressures. Relatively cheap wooden molds are required to build quite large items such as tanks and ducting on a one-off basis. The principal materials in this group of plastics are described below. [Pg.119]

Relative Vapor Pressure of Solid and Liquid. If the dissolved solids in a liquid have a low vapor pressure relative to the liquid in which they are dissolved, provided the solid is not affected by the liquid boiling point, it is an easy matter to vaporize the liquid, leaving a dry residue. [Pg.165]

Gas storage cabinets consist of a box that encloses the tank(s) and all connections. Many include change out capabilities and an access door. The cabinets are exhausted to remove any contaminant that may leak into the cabinet and to maintain the cabinet under negative pressure relative to the... [Pg.894]

Psychrometry has to do with the properties of the air-water vapor mixtures found in the atmosphere. Psychrometry tables, published by the US Weather Bureau, give detailed data about vapor pressure, relative humidity and dew point at the sea-level barometer of 30 in Hg, and at certain other barometric pressures. These tables are based on relative readings of dry bulb and wet bulb atmospheric temperatures as determined simultaneously by a sling psychrometer. The dry bulb reads ambient temperature while the wet bulb reads a lower temperature influenced by evaporation from a wetted wick surrounding the bulb of a parallel thermometer. [Pg.635]

Check the condenser absolute pressure. An increase in the condenser back-pressure, relative to design, is a sign of fouled tubes, air leakage, or poor overall cooling tower system performance. [Pg.119]

Human blood has an osmotic pressure relative to water of approximately 7.7 atm at body temperature (37°C). In a hospital, intravenous glucose (C6H)2Ofc) solutions are often given. If a technician must mix 500.111L of a glucose solution for a patient, what mass of glucose should be used ... [Pg.473]

Author and Heat flux Inlet flow Pressure Relative Fluid... [Pg.270]

All laboratory operations are carried out in laminar flow cabinets in rooms in which filtered air is maintained at a slight positive pressure relative to their outer environment. Operators wear sterilized clothing and work aseptically. Antibiotic fermentations are, of strict necessity, pure culture aseptic processes, without con-tamirrating orgarrisms. [Pg.151]

Blast wave (Overpressure and negative phase pressure relative to atmospheric condition) Diffraction loading—forces on a structure resulting from the direct and reflected overpressure... [Pg.31]

Bending moments caused by eccentricity of the centre of the working pressure relative to the neutral axis of the vessel. [Pg.814]

Polymorphs are different crystal forms of the same compound [55], They are usually prepared by crystallization of the drug from different solvents under diverse conditions. However, exposure to changes in temperature, pressure, relative humidity, and comminution which are encountered in processes such as drying, granulation, milling, and compression may also lead to polymorphic transformations. [Pg.152]

Both adsorptive and capillary forces play an important part in soil-liquid interaction (see Figure 18.3). This is very important for unsaturated soil. The total force (i.e., the sum of capillary force and adsorptive force) is termed the matrix potential, which has a negative gage pressure relative to the external gas pressure on the soil water (more often the gage pressure is referred to as the atmospheric pressure). [Pg.698]

However, there are also conditions under which this law provides a very good representation of the density for virtually any gas. In general, the higher the temperature and the lower the pressure relative to the critical... [Pg.267]

Calculate the volume of hydrogen gas, measured at room temperature and pressure, which would be formed when 12 g of magnesium react with excess dilute sulphuric acid (assume that one mole of any gas occupies a volume of 24,000 cm3 (24 dm3) at room temperature and pressure relative atomic mass of... [Pg.31]

ArV is not necessarily positive, and to compare the relative stability of the different modifications of a ternary compound like AGSiOs the volume of formation of the ternary oxide from the binary constituent oxides is considered for convenience. The pressure dependence of the Gibbs energies of formation from the binary constituent oxides of kyanite, sillimanite and andalusite polymorphs of A SiOs are shown in Figure 1.10. Whereas sillimanite and andalusite have positive volumes of formation and are destabilized by pressure relative to the binary oxides, kyanite has a negative volume of formation and becomes the stable high-pressure phase. The thermodynamic data used in the calculations are given in Table 1.7 [3].1... [Pg.23]

Overpressure - Is any pressure relative to ambient pressure caused by a blast, both positive and negative, sometimes referred to as "psio". [Pg.58]

Other examples of nonionic compounds (Fig. 10, Table 3) are the phenyl-amide herbicides (e. g., Diphenamid, moderately water soluble and nonvolatile), thiocarbamate, and carbothioate herbicides (e. g., Thiobencarb, low water solubility, high vapor pressure, relative mobility in soil systems) and benzonitrile herbicides (e.g., Dichlobenil, low water solubility, low vapor pressure, relative immobility in most soils) [151]. [Pg.31]

From the preceding discussion it should be clear that the level of isotopic fractionation for a major rock-forming element like Mg in an object that was once molten in the early Solar System is a barometer of either total pressure (large F) or partial pressures relative to saturation (small F). In order to use Mg as a cosmobarometer, high-precision analyses of Mg isotope ratios in both chondrules and C AIs are required. [Pg.225]

The amounts of water absorbed as function of relative water vapor pressure (relative humidity) for HA and its esters are reported in Tables 1-4. HA absorbed the highest amount of water at all humidity levels compared to its esters. The ethyl ester (Hyaff ) absorbs more water than the other two, and the dodecyl ester (Hyaff73) absorbs more water than the benzyl ester (Hyaffll). A small percentage of water absorption hysteresis, between sorption and desorption, was found for the four different materials analyzed. No significant differences in the percentage of hysteresis was found among the HA and the three esters. [Pg.177]

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