Electrostatic sampler

Effects of carrier gas flow rate, dilution flow rate, and the combustion boat temperature were studied by sampling the aerosol stream with an electrical aerosol analyzer to obtain the particle size distribution. Filter samples were taken for chemical analysis to determine mass concentrations. Aerosol samples were also collected in an electrostatic sampler for electron microscopic examination. 

Volckens, J. and Leith, D., Electrostatic sampler for semivolatile aerosols chemical artifacts. Environ. Set Technol, 36, 4608-4612, 2002. 

To test this approach to online size characterization of CNTs, multi wall carbon nanotubes (MWNTs) ranging from 10 to 100 nanometers in diameter and 0.5 to 40 trm in length with a purity of 95% were aerosolized and the DMA was used to size-select CNTs by their electrical mobility. These CNTs were subsequently collected directly onto TIM grids using an electrostatic sampler. Transmission electron microscopy was used to determine the dimensions of the carbon nanotubes. These dimensions were then used to test the methodology, and the results are presented in Section 9.3.5. 

The electrostatic sampler used a strong electric field to collect the carbon nanotubes on holey carbon TEM grids. The use of an electrostatic sampler ensured that no sampling bias occurred. The importance of sampling without bias is discussed further in Section 9.4.1. Finally, the CNTs collected were observed using a transmission electron microscope (see Section 9.4). Diameters and lengths were obtained for the nanotubes and the results were used to test the electrical mobility theory and charge expression. 

Textile mill dusts investigated include samples collected using a vertical elutriator cotton dust sampler, seunples of fine dust separated mechanically from carding filter cake material, Scimples collected on electrostatic precipitators in a card room, coarse condenser trash from a card room, and weave room dusts. 

Wall losses were estimated by comparing the mass concentrations of various elemental constituents of aerosols collected with a series of alternately collected filter and impactor samplers. For samples collected downstream of an electrostatic precipitator (ESP), where the aerosol MMAD was 11.5 pm, the average amount of mass collected in the impactors was about 60% of that collected by the filters (Table... 

Example 13.3 An electrostatic precipitator sampler consists of a 0.020-indiameter wire placed along the axis of a 1.5-in-diameter tube. What is the maximum field strength (assuming negligible space charge) at the outer edge of the tube when the precipitator voltage is 20 kV ... 

Tel. 703-658-4854, fax 703-658-4887, e-mail syazdi presto.ig.com Desktop molecular modeling. NEMESIS SAMPLER for simple modeling. PRO-EXPLORE for sequence analysis and biomolecular modeling. PRO-SIMULATE for molecular simulations with GROMOS, AMBER, and BOSS via a graphical interface. PRO-QUANTUM for semiempirical (MOPAC, extended Hiickel) and ab initio (CADPAC) calculations via a graphical interface. FDCALC and ESCALC for electrostatics calculations. N-DEE for analysis of NMR data. PC-PROT-I- (sequence analysis), PC-TAMMO-I- (protein—lipid modeling), and MASCA (statistics). Macintosh, PCs, and UNIX workstations. 

The TSI Model 3100 Electrostatic Aerosol Sampler collects and deposits particles ranging from 0.02 to 10 pm onto a collection substrate. It does not collect large samples quickly. The samples may be collected directly onto glass slides, metal foil, plastic sheets, or coated electron microscope grids. 

Apart from these fundamental improvements via procedural change, a number of further measures are specified in Table 9.15, with which a sustainable reduction of the emissions during ore smelting can be achieved (Elgersma etal. 1995). For air pollution abatement from heavy metals, the use of highly effective woven filters as a replacement of electrostatic dust samplers... 

Debye length The distance over which ions exert an electrostatic influence over one another as they move from the interface region into the ion optics. In the ionsampling process, this distance is small compared to the orifice diameter of the sampler or skimmer cone. As a result, there is little electrical interaction between the ion beam and the cones, and relatively little interaction between the individual ions within the ion beam. In this way, the compositional integrity of the ion beam is maintained throughout the interface region. 

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