Finely Dispersed Particles

Sprays. Aerosol spray emulsions are of the water-in-oil type. The preferred propellant is a hydrocarbon or mixed hydrocarbon—hydrofluorocarbon. About 25 to 30% propellent, miscible with the oil, remains in the external phase of the emulsion. When this system is dispensed, the propellant vaporizes, leaving behind droplets of the w/o emulsion (Fig. 2b). A vapor tap valve, which tends to produce finely dispersed particles, is employed. Because the propellant and the product concentrate tend to separate on standing, products formulated using this system, such as pesticides and room deodorants, must be shaken before use. 

The technique of rapid soHdification enables relatively large amounts of insoluble metallic elements to be finely dispersed within atomized powders. Upon freezing very small intermetaUic particles are formed, resulting, after further processing, in a high volume fraction of finely dispersed particles within the aluminum matrix and hence a dispersion strengthened aUoy. The intermetaUic phases, or possibly oxidic species, responsible for the dispersion strengthening are probably binary Al-Fe and ternary Al—Fe—Ce compounds. 

Through these processes dissolved substances and/or finely dispersed particles can be separated from liquids. All five technologies rely on membrane transport, the passage of solutes or solvents through thin, porous polymeric membranes. 

EXPLOSION Finely dispersed particles form explosive mixtures in air. Prevent deposition of dust closed system, dust explosion-proof electrical equipment and lighting. Prevent build-up of electrostatic charges (e.g., by grounding). ... 

Fine dispersed particles 12- 25 - X 58-80 Permeability independent of EVOH cone. 

Yellow, rhombic crystals or powder. Finely dispersered particles form explosive mixtures. Combustible. 

Process in which a precipitant is added incrementally to a highly dilute polymer solution and the intensity of light scattered by, or the turbidity due to, the finely dispersed particles of the polymer-rich phase is measured as a function of the amount of precipitant added. 

Considerable difficulties are presented when solid impurities (dirt) are separated from the diethylaluminumchloride solution. Impurities as a rule consist of finely dispersed particles of sodium chloride and highly flam-... 

Finely Dispersed Particles Micro-, Nano-, and Atto-Engineering, edited by Aleksandar M. Spasic and Jyh-Ping Hsu... 

In order to understand the nature of radiocolloids, knowledge of the general properties of colloids is needed. Colloids are finely dispersed particles in a liquid phase, a gas phase or a solid. The size of colloidal particles is in the range between that of molecules or ions and that of particles visible by means of a light microscope, i.e. between about 1 nm and about 0.45 pm. The upper value corresponds to the mean wavelength of visible light. Large molecules, in particular polymers and biomolecules, approach or exceed the upper value and may also form colloids. 

Ruthenium in RU-C0/AI2O3 is in Ru and RUO2 forms (Ru3p3/2 = 460,8 - 461,8 eV) and cobalt is in oxidized state with Co2p3/2 = 777,8 - 780,0 eV. However separate spots of a-Co and (i-Co have been found by electron microscopy. Also the fine dispersed particles have been observed, its amount was increased with the rise of Co concentration and got maximum when content of Co was 70%. These particles were X-Ray amorphous. Oxidized states of Co bonded with tiny particles of Ru were presented in these formations. The clusters formation is available. Particles of Ru bonded with AI2O3 have been also found. 

Thus, the results of studies on sorption properties of adsorbents synthesized at elevated temperatures are affected by some factors whose action, as shown by the analysis, is directed towards reducing parameters of the structure of adsorbents produced. It is more difficult to answer the question about the contribution of each of them to this process and to estimate their effects. The difficulty consists in the fact that the effects of these factors are simultaneous and it is impossible to neglect at least one of them. It is only possible to suggest that the following two factors are the most effective decrease of association in solution that is responsible for formation of fine disperse particles and destabilization of their aggregative state, which facilitates formation of the crystal phase. It is a joint action of these factors that largely determines properties of the materials synthesized. 

The catalyst is usually coated onto its support in the shape of finely dispersed particles. The choice of the two materials is crucial to both producf s quality and quantity. For ejample, the linkage of catalyst and support must be stable also at high temperatures. A large catalyst surface and a low tendency to aggregation further favor the growth of SWNT. Alumina and sihca constitute typical substrates, but silicon itself or certain metals are suitable as well. 

SILICON OXIDE or SILICON(II) OXIDE (10097-28-6) Highly flammable solid. Dust, powder, or other finely dispersed particles may self-ignite in air. A strong reducing agent. 

Elektrostatisch unterstiitztes Mischen feinkomiger Partikel (Electrostatically assisted mixing of finely dispersed particles)... 

HAZARD RISK Closed containers may explode when exposed to heat or flame finely dispersed particles form explosive mixtures in air forms explosive mixtures with diethyl phosphite and potassium hydroxide exothermic decomposition emits toxic fumes of carbon monoxide, carbon dioxide and nitrogen oxides NFPA Code H 3 F 1 R 0. 

EXPLOSION and FIRE CONCERNS noncombustible solid in bulk form flammable gas as dust or in powder form finely dispersed particles form explosive mixtures in air reacts with oxygen difluoride causing fire hazard violent reaction with bromine trifluoride, chlorine trifluoride and bromine pentafluoride in case of fire in the surroundings, all extinguishing agents are suitable for firefighting purposes. 

The milk then enters a cyclone vessel tangentially. Coarser particles remain close to the wall of the vessel and are drawn back into the mixing chamber by a tangential off-take. The finely dispersed particles are drawn from the centre of the cyclone vessel into a stirred vessel. In that vessel, the milk is subjected to further high shear rates and is diluted with cold water to the required concentration. 

A suspension of finely dispersed particles is thermodynamically unstable this system is inclined to lower its free energy through flocculation. The stability and rheology of a powder in a suspension depend on the nature of the solid/ solution interface, particularly on the electrical properties of this region [70]. This interface may be described as consisting essentially of two layers (Fig. 3) ... 

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