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Dispersion uniform

For tray columns, bubble caps, valves or sieve, the feed liquid usually enters the column either in between functioning trays or at the top (reflux). The liquid or liq-uid/vapor mixture for flashing liquids must be dispersed uniformly across the tray. Such an arrangement often requires a special tray designed for the purpose to allow... [Pg.131]

TPEs from thermoplastics-mbber blends are materials having the characteristics of thermoplastics at processing temperature and that of elastomers at service temperature. This unique combination of properties of vulcanized mbber and the easy processability of thermoplastics bridges the gap between conventional elastomers and thermoplastics. Cross-linking of the mbber phase by dynamic vulcanization improves the properties of the TPE. The key factor that controls the properties of TPE is the blend morphology. It is essential that in a continuous plastic phase, the mbber phase should be dispersed uniformly, and the finer the dispersed phase the better are the properties. A number of TPEs from dynamically vulcanized mbber-plastic blends have been developed by Bhowmick and coworkers [98-102]. [Pg.1055]

The fineness characteristic of a powder on a cumulative basis is represented by a straight line from the origin to 100 per cent undersize at a particle size of 50 un. If the powder is initially dispersed uniformly in a column of liquid, calculate the proportion by mass which remains in suspension in the time from commencement of settling to that at which a 40 i m particle falls the total height of the column. It may be assumed that Stokes law is applicable to the settling of the particles over the whole size range. [Pg.13]

TOF-SIMS images (Figs. 13.5 and 13.6) illustrate the ability to detect changes in the dispersion (uniform or presence of metal clusters) of the active phase in supported-oxide catalysts. Figure 13.5 shows nearly uniform distribution of molybdenum. The surface contamination with NH4+ ions coming from a precursor, which were not removed during the catalyst preparation process, is also observed. Cobalt clusters in the range of several micrometers are clearly visible in Fig. 13.6. [Pg.281]

Uniformly dispersed Uniform solution Uniform mixture... [Pg.816]

At the end of the polymerisation, we have fine particles of the polymer, stabilised by the emuisifier layer and dispersed uniformly in the aqueous phase. This milky white dispersion is often called... [Pg.18]

Since the substrate hematite contains Fe-57, a certain Mossbauer self-absorption is inevitable in the case of measurements on Co-57. But, the effect of the absorption is considered to be not important as far as the pH dependence of the spectra is concerned, since the amount of hematite was kept constant and the adsorbed divalent Co-57 was dispersed uniformly in it. [Pg.406]

The TEM images (Fig. 6.14a) show that Ag nanoparticles about 5 nm are dispersed uniformly in Si02 carrier before the Ag/Si02 composite prepared by the one-step method is calcined. With the increase of the calcination temperature, Ag nanoparticles grow out from the Si02 carrier. Ag nanoparticles are about 10 nm and disperse on the surface of the Si02 carrier when the composite is calcined at 450°C (Fig. 6.14b). [Pg.86]

Figure 6 shows the surface of the 50°C annealed membrane, where we can observe the existence of cavities, the sizes of which are between 25 and 50 A. Upon annealing, the fine pores as observed in the unannealed one disappeared and the cavities (25 -50 A) were dispersed uniformly on the surface. The features of the surface are very different from those of the unannealed one. [Pg.251]

Supported vanadium oxides represent one of the technologically most important class of solid catalysts. These catalysts are useful for partial oxidation of various hydrocarbons 0), ammoxidation of alkyl substituted N-heteroaromatic compounds (2) and most recently for NO reduction (3) For a catalyst to be a successful one in industry, it should exhibit high activity with maximum selectivity, thermal and mechanical stability and long life etc. For getting some of these functionalities, the active component has to be dispersed uniformly on a support material. [Pg.204]

While precipitation in homogenous solutions is an exceedingly simple method, usually rather low concentrations of electrolytes must be used if well-dispersed uniform particles are to be achieved. This requirement is based on the need to keep the ionic strength of the system below a critical value in order to prevent the coagulation of the precipitates, which consist, almost without exception, of charged particles. In some instances, concentrations of the reactants can be increased, if stabilizers are added into the systems, although the latter may affect the particle uniformity and/ or shape. [Pg.5]

Eadie, in Ref 69, reports on a considerable amount of work done on the ability of beeswax and paraffin wax to remain coated on HMX surfaces when immersed in liq TNT. Thru measurements of contact angles, a technique used earlier on RDX/wax systems reported on by Rubin in Ref 23, it was determined that the TNT preferentially wets the HMX and the wax is stripped away. He concludes that the most important property of a desensitizing wax is that it should be readily dispersed uniformly thruout the TNT phase. He also suggests that a better desensitizer for investigation for use would be a wax or substituted hydrocarbon having a low interfacial tension with TNT. The smaller the wax droplet size the more efficiently it will be distributed and the more effectively it should desensitize. Williamson (Ref 64) in his examination of the microstructures of PETN/TNT/wax fusion-casts detected that wax is dispersed thru the cast as isolated descrete globules which he refers to as blebs or irregular or streak-like areas, surrounded by TNT (see also Ref 54)... [Pg.331]

Color Plate 31 Colloids and Dialysis (Demonstration 27-1) (a) Colloidal Fe(III) (left) and ordinary aqueous Fe(III) (right). (J ) Dialysis bags containing colloidal Fe(III) (left) and a solution of Cu(ll) (right) immediately after placement in flasks of water, (c) After 24 h of dialysis, the Cutll) has diffused out and is dispersed uniformly between the bag and the flask, but the colloidal Fe(III) remains inside the bag. [Pg.366]

The dye should become dispersed uniformly within the hot water first. The higher the temperature, the greater the average kinetic energy of the molecules. Because the molecules within the hot water are moving faster, they have a quicker effect on the dye of the Kool-aid crystals. Furthermore, the hot water will tend to have more convection currents that will also help to distribute the dye throughout the water. [Pg.682]

Note The operations described above are applicable to any single-base proplnt. In order to prepare a double-base proplnt, the required amt of NG(or NG + NGc) in a suitable solvent is added at this stage of the process and dispersed uniformly throughout the quasi-emulsion. Substances like DNT, TNT, DBuPh, centralites, etc may be incorporated, if desired in the same manner as NG... [Pg.12]

Breads or muffins enriched in [3-glucan may be produced using oat or barley flour or bran, as well as coarser particles such as oat flakes or cracked barley. Coarser particles tend not to disperse uniformly in a dough. Therefore, it is important to obtain a representative sample from such products in order to have uniformly distributed P-glucan-rich particles. [Pg.749]

In both systems, the active is first dispersed uniformly in a solution or gel. In the reservoir system, the homogeneous gel is dispensed onto a card that is then die-cut to yield individual systems. These systems are then pouched. In the matrix system, the mixed solution is uniformly coated onto the surface of a film. The resulting laminate is then die-cut into individual systems and pouched. [Pg.279]

Equipment suitable for accurately weighing and dispensing small quantities of ingredients should be available. Care is necessary in handling premixes. Before being added into the mix these should be admixed with ground cereal to make up at least 5% of the total mix. This is to ensure that the premix disperses uniformly through the mix. [Pg.237]

Mixing of oxidant and wastewater formation of a dispersed, uniform spray. [Pg.646]

Two types of reference are used in NMR—Internal and external. An internal reference is a compound giving a sharp NMR line that is dissolved directly in the sample solution under study. The reference substance is then dispersed uniformly at a molecular level through the sample. The magnetic field acts equally on the sample and reference molecules, so that Eq. 4.6 and the other relations derived before are completely valid. Provided the reference compound does not react chemically with the sample, the only serious drawback of an internal reference is the possibility that intermolecular interactions might influence the resonance frequency of the reference. Usually, by careful choice of relatively inert... [Pg.89]

Consider a solution of an electrolyte MX to which a certain amount of radioactive M ions are added in the form of the salt MX. Further, suppose that the tracer ions are not dispersed uniformly throughout the solution instead, let there be a concentration gradient of the tagged species so that its diffusion flux Jp is given by Fick s first law... [Pg.449]

A variation of the indicator dilution method (see preceding problem) is used to measure total blood volume. A known amount of a tracer is injected into the bloodstream and disperses uniformly throughout the circulatory system. A blood sample is then withdrawn, the tracer concentration in the sample is measured, and the measured concentration [which equals (tracer injected)/(total blood volume) if no tracer is lost through blood vessel walls] is used to determine the total blood volume. [Pg.163]

In the preceding example, it was shown that 2,240 lb. of phosgene are required to establish a concentration of 1 10,000 on a target 500 by 1,000 ft. at a distance of 2,000 ft, (667 yd.) from the line of emission. If the phosgene could be rele sed on the target and dispersed uniformly thereover, it would require only... [Pg.200]


See other pages where Dispersion uniform is mentioned: [Pg.55]    [Pg.305]    [Pg.795]    [Pg.975]    [Pg.384]    [Pg.5]    [Pg.116]    [Pg.502]    [Pg.192]    [Pg.84]    [Pg.202]    [Pg.277]    [Pg.55]    [Pg.293]    [Pg.626]    [Pg.373]    [Pg.226]    [Pg.476]    [Pg.274]    [Pg.53]    [Pg.497]    [Pg.287]    [Pg.613]    [Pg.258]    [Pg.266]    [Pg.494]    [Pg.147]   
See also in sourсe #XX -- [ Pg.96 ]




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