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Aerosols electrical properties

W. Jutzi, Beitrag zur Kenntnis der electrischen Eigenschaften grobkolloider Aerosole (Electric Properties of Coarse Aerosols), Dusseldorf (1954). [Pg.432]

Atmospheric ions are important in controlling atmospheric electrical properties and conmumications and, in certain circumstances, aerosol fomiation [128. 130. 131. 138. 139, 140. 141. 142, 143, 144 and 145]. In addition, ion composition measurements can be used to derive trace neutral concentrations of the species involved in the chemistry. Figure A3.5.11 shows the total-charged-particle concentration as a frmction of... [Pg.817]

Davies (D2) has given a very brief review of some of the recent literature related to electrical properties of aerosols. [Pg.6]

Experimental methods presented in the literature may prove of value in combustion studies of both solid and liquid suspensions. Such suspensions include the common liquid spray. Uniform droplets can be produced by aerosol generators, spinning disks, vibrating capillary tubes, and other techniques. Mechanical, physicochemical, optical, and electrical means are available for determination of droplet size and distribution. The size distribution, aggregation, and electrical properties of suspended particles are discussed as well as their flow and metering characteristics. The study of continuous fuel sprays includes both analytical and experimental procedures. Rayleigh s work on liquid jet breakup is reviewed and its subsequent verification and limitations are shown. [Pg.137]

Several electrical properties may be of interest in aerosol studies. These could include the distribution of charges carried by aerosol particles and the velocity of a charged particle in an electric field. This latter property, e.g., is important in determining such things as deposition rates or charge transfer rates. [Pg.299]

Atmospheric gaseous ions not only control the electrical properties of the atmospheric medium but also have an interesting role in atmospheric chemistry. They have the potential to stimulate the formation of aerosols by ion-induced nucleation [1, 4] and to form or destroy trace gases by ion-molecule or ion-catalyzed reactions. Apart from these active roles ions also have an interesting passive role in serving as powerful probes... [Pg.103]

First, aerosol particles are important from the point of view of atmospheric electricity. A fraction of the air molecules is electrically charged (small ions), as a result of ionizing radiation. Measurements show (Bricard and Pradel, 1966) that in 1 cm3 of surface air about 10 ion-pairs are formed each second. Eight out of ten are produced by the radioactivity of the air and soil, while the other two are produced by cosmic radiation. The electrical properties of the air are determined by the electrical mobility (B) of ions formed ... [Pg.97]

Analogously, for any other fluctuating value, the average square fluctuation equals the ratio of kT to the second derivative of work (free energy) of fluctuations with respect to the fluctuating parameter. We will utilize this approach in describing the optical properties of disperse systems (further down in this chapter), the electric properties of aerosols (see Chapter VIII), and the conditions of the formation of critical emulsions (see Chapter VI,2). [Pg.343]

Among all disperse systems the aerosols, in which the dispersion medium is a gas, are unique. These systems are principally lyophobic, and their stabilization, e.g. by introduced surfactants, is ineffective. Aerosols reveal also some specific electric properties. [Pg.583]

No agnifkant diffelectric properties of the fibers do not influence their soiling tendency by aerosols. [Pg.126]

Aerosol Nanoparticle Electrical properties Filtration Nanoaerosol Nanoaerosol characterization Nanoaerosol dmg dehvery Nanoaerosol dynamics Occupational exposure Thermal rebound... [Pg.2336]

Because of the excellent electrical properties, PTEE is used in a variety of electrical applications, such as wire and cable insulation and insulation for motors, capacitors, coils, and transformers. PTFE is also used for chemical equipment such as valve parts and gaskets. The low friction characteristics make PTFE suitable for use in bearings, mold release devices, and antistick cookware. Low-molecular-weight polymers may be used in aerosols for dry lubrication. ... [Pg.64]

Adamyan AZ, Adamian ZN, Aroutiounian VM, Schierbaum KD, Han S-D (2009) Improvement and stabflization of thin-lilm hydrogen sensors parameters. Armenian J Phys 2(3) 200-212 Akedo J, Lebedev M (1999) Microstructure and electrical properties of lead zirconate titanate (Pb(Zr, film deposited with aerosol deposition method. Jpn J Appl Phys 38 5397-5401 Andersen SK, Johannessen T, Mosleh M, Wedel S, Tranto J, Livbjerg H (2002) The formation of porous membranes by filtration of aerosol nanoparticles. J Nanopart Res 4 405-416... [Pg.294]

Some nanoparticles are intentionally engineered and produced with very specific properties in mind such as shape, size, surface properties and chemistiy. These properties are reflected in aerosols, colloids, or powders. Often, the behavior of nanomaterials may depend more on surface area than particle composition itself. Relative-surface area is one of the principal factors that enhance its reactivity, strength and electrical properties. Some examples of these engineered nanomaterials are carbon buckyballs or fullerenes carbon nanotubes metal or metal oxide nanoparticles (e.g., gold, titanium dioxide) quantum dots, etc. [Pg.290]

Dry aerosols, or particulate matter, differ so much from the carrying gas stream that their removal should present no major difficulties. The aerosol is different physically, chemically, and electrically. It has vastly different inertial properties than the carrying gas stream and can be subjected to an electric charge. It may be soluble in a specific liquid. With such a variety of removal mechanisms that can be applied, it is not surprising that particulate matter, such as mineral dust, can be removed by a filter, wet scrubber, or electrostatic precipitator with equally satisfactory results. [Pg.462]

K6. Kraemer, H. F., Properties of electrically charged aerosols, Univ. of Illinois, Eng. Exptl. Sta. Tech. Rept. 12, AEC Rept. COO-1013, Contr. AT(ll-l)-276 (1954). [Pg.94]

One characteristic of phase boundaries, especially those involving an aqueous phase, is the probable existence of an electrical potential across the interface. Although such charge phenomena an not always present, when in existence, they have an enormous impact on system properties. Chargi effects are usually most important in aqueous suspensions, emulsions, foams, aerosols, and othe dispersions in which one phase is Lnely divided in another phase, creating a large interfacial area. [Pg.259]

For nonspherical particles, Muller (1928) postulated that since the diffusion equation applicable to aerosol problems is the same (except for definition of terms) as the general equation for electric fields (Laplace s equation), there should be analogs among the electrostatic terms for various properties of coagulation. For example, the potential should be analogous to particle number concentration, and field strength to particle agglomeration rate. Zebel (1966) pointed out that... [Pg.169]

The steady-state distribution is independent of the ionic concentration. However, the rate of approach to the steady state depends on the ionic concentrations and other properties of the system. The net result can be summarized as follows for the atmosphere. Ions are steadily generated by cosmic rays and radioactive decay processes. These attach to particle surfaces where they are neutralized at a rate equal to their rate of formation. The particle charge distribution is determined by the steady state relationship between particles separated by one charge. In the atmosphere, the equilibration process takes about 30 min. The rate of equilibration can be increased by increasing the ion concentration using a bipolar ion generator. Radioactive ion sources such as are often used in electrical aerosol instrumentation (Chapter 6). [Pg.49]


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