Pressure, static

It is difficult to determine exactly the areas of localized pressure reductions inside the pump, although much research has been focused on this field. It is easy, however, to measure the total fluid pressure (static plus dynamic) at some convenient point, such as pump inlet flange, and adjust it in reference to the pump centerline location. By testing, it is possible to determine the point when the pump loses performance appreciably, such as 3% head drop, and to define the NPSH at that point, which is referred to as a required NPSH (NPSHR). The available NPSH (NPSHA) indicates how much suction head... 

Chile [Prog. Aerosp. Sc7, 16, 147-223 (1975)] reviews the use of the pitot tube and allied pressure probes for impact pressure, static pressure, dynamic pressure, flow direction and local velocity, sldn friction, and flow measurements. 

In such openings, bidirectional flow driven by temperature differences between the two rooms can occur. If a total pressure (static pressure plus dynamic pressure) is specified, this phenomenon can be accounted for. For higher accuracy in the neighborhood of this opening, it is, however, recommended to expand the calculation domain beyond this opening. 

Pressure, static The potential pressure that is exerted in all directions by a fluid at rest. 

Tower Operating Pressure Static Slot Seal [15], In. Dynanuc Slot Seal [5],In. 

This is really a simple form of axial fan but with its impeller mounted in a ring or diaphragm which permits it to discharge air with both axial and radial components. Duties covered are high volume and low pressure. Static efficiency is normally under 40 per cent. 

Absolute unit of pressure = Statical units of j>ressure = ... 

The confined type of aquifer has a hydraulic pressure (static head) that is on a higher level than the top of the aquifer. This artesian pressure can sometimes reach above the surface level resulting in self flowing wells (artesian wells). 

It must be also considered that the reaction rates of different thermal processes which can occur simultaneously are influenced by the treatment conditions (temperature, heating rate, pressure, static or dynamic atmosphere). This will affect the relative quantities of the products formed and in some cases also their nature, when recombination reactions give rise to secondary degradation products. On account of its sensitivity and resolution power Py-GC/MS will also provide useful information on minor components present in a material, including low molecular weight additives and pigments. 

The exp-6 potential has also proved successful in modeling chemical equilibrium at the high pressures and temperatures characteristic of detonation. However, to calibrate the parameters for such models, it is necessary to have experimental data for product molecules and mixtures of molecular species at high temperature and pressure. Static compression and sound-speed measurements provide important data for these models. 

Fig, 6. Rates of methylcyclopentane formation from 3-methylpentane, as a function of hydrogen pressure. Static-circulation system catalyst, 0.16 g platinum black hydrocarbon pressure, 5 Torr (77). 

We have seen earlier in this chapter how the self-assembly of casein systems is sensitively affected by temperature. Another thermodynamic variable that can affect protein-protein interactions in aqueous media is the hydrostatic pressure. Static high-pressure treatment causes the disintegration of casein micelles due to the dismption of internal hydro-phobic interactions and the dissociation of colloidal calcium phosphate. This phenomenon has been used to modify the gelation ability of casein without acidification as a consequence of exposure of hydrophobic parts of the casein molecules into the aqueous medium from the interior of the native casein micelles (Dickinson, 2006). High-pressure treatment leads to a reduction in the casein concentration required for gelation under neutral conditions, especially in the presence of cosolutes such as sucrose (Abbasi and Dickinson, 2001, 2002, 2004 Keenan et al., 2001). 

A number of analogous compounds to BA have been reported, including 5,5 -dibenzo-[a]-pyrenyl (BBPY) [116]. These compounds exhibit emission spectra similar to BA. It would be interesting to explore the ultrafast dynamics of BBPY in order to test the generality of the GLE model. It would also be interesting to study the femtosecond dynamics of BA as a function of applied pressure. Static experiments on the emission of BA, reported by Hara et al. [123], demonstrate that in low viscosity solvents an increase of pressure affects the emission similarly to an increase of solvent polarity. As the pressure is increased, however, the LE/CT interconversion is slowed down. It would be interesting to measure C(r) in these environments and compare the solvation dynamics with LE/CT dynamics, in order to test the generality of the GLE dielectric friction model. 

High-pressure static and dynamic light scattering were used to closely examine the behavior of block copolymers of poly(vinyl acetate) (PVAc) and poly(l,l,2,2-tetrahydroperfluoroalkyl acrylate (PTAN) as a function of C02 density (Buhler et al., 1998). The phase diagram for PVAc-6-TAN shows three distinct phases as a function of polymer concentration and C02 density at a fixed temperature of 45 °C (see Figure 9.1). The block copolymer forms a precipitated phase at low C02 densities, spherical micelles at intermediate C02 densities, and unimers, or free polymer chains in solution, at high densities. The micelles-to-unimer transition was found to be very... 

In situ adsorption cells enable adsorption under gas flow (dynamic mode) or under pressure (static mode). The catalysts are generally studied afler pre-treatment, under specific gases or under secondary vacuum, at high temperature. Adsorption may be carried out between 450 C and liquid nitrogen temperature depending on the material used. 

Straightforward measurements of elastic properties of materials can be made via high-pressure static compression experiments, in which X-ray diffraction (XRD) is used to measure the molar volume (V), or equivalently the density (p), of a material as a function of pressure (P). The pressure dependence of volume is expressed by the incompressibility or isothermal bulk modulus (Kt), where Kp = —V(bP/bV)p. 

The components of an ELM system are the diluent, surfactant, internal aqueous phase, continuous phase, and carrier in the case of type 2 facilitation. Emulsification is usually achieved by high speed or ultrasonic stirrers for batch operations and high-pressure static dispersion or colloid mills for continuous mode [46]. The presence of a surfactant is necessary to ensure adequate stability of the emulsion during the extraction process. However, an ultra stable emulsion is not desirable as it will lead to difficulties in the demulsification stage. Eor the effective working of an ELM all components must be carefully chosen and each composition is critical. Some of the desirable properties of the various components are listed in the following sections. 

Column diameter, Tray Pressure, Static Effif ty, ... 

The motivation for the cluster model is to determine the simplest possible model that will match both the low pressure static compression of supercritical HF, and the shock Hugoniot of PVF2. The current model succeeds in this regard, although we caimot claim that the description of individual cluster species is quantitatively accurate. We have found that it is possible to match the shock Hugoniot of PVF2 without the association model, but the static compression requires an explicit treatment of association. We decided to limit our model to only those clusters described by JANAF. 

Total Pressure = Static Pressure + Velocity Pressure. 

Pressure Static Recovery tests were modelled (within a purely-hydraulic computation) in order to calibrate fractures storativity. The difference between computed storativity, which takes only joint aperture into account, and calibrated storativity reveals the major role played by rock... 

Chromium(V) fluoride has been prepared by the static fluorination of chromium powder by elemental fluorine at 400° and 200 atm and by the high temperature, high-pressure static fluorination of chromium(III) fluoride. The procedure described below involves fluorination of chromium(VI) difluoride dioxide, Cr02p2, by elemental fluorine under rather mild conditions, which is the most convenient method. Chromium(V) fluoride is a useful precursor to a large number of complex salts that contain CrP and Crp7. ... 

Ruan, K and Balny, C, 2002, High pressure static fluorescence to study macromolecular structure-function. Biochimica Biophysica Acta. Proteins and Proteomics. 1595, 94-102. 

The electronic flow measurement for custody transfer system consists of a microcomputer, s chromatgraph, H20 and H2S analyzer, a differential pressure, static and temperature transducers for each... 

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