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Residue particles

As an example, consider heavy fuel oil (CH15, specific gravity, 0.95) atomized to a surface mean particle diameter of d, burned with 20 percent excess air to produce coke-residue particles having the original drop diameter and suspended in combustion products at 1204°C (2200°F). The flame emissivity due to the particles along a path of L m will be, with d in micrometers. [Pg.582]

Disruption of an agglomerated particle L, S), produces a single primary crystal (Ld, 1) and the residual particle (Ldd, —1). Conservation of crystal mass balance requires the following equations to be satisfied ... [Pg.246]

When such an electrode is discharged by removal of the electroactive species, the residual particles of the reactant phase remain as relics in the microstructure. This provides fixed permanent locations for the reaction to take place during following cycles, when the electroactive species again enters the structure. Thus this type of con-... [Pg.375]

Table 3 Defect (white residue particle) diameters measured from Figure 4... Table 3 Defect (white residue particle) diameters measured from Figure 4...
The above observation suggests an intriguing relationship between a bulk property of infinite nuclear matter and a surface property of finite systems. Here we want to point out that this correlation can be understood naturally in terms of the Landau-Migdal approach. To this end we consider a simple mean-field model (see, e.g., ref.[16]) with the Hamiltonian consisting of the single-particle mean field part Hq and the residual particle-hole interaction Hph-... [Pg.104]

Alternatively stated, the losses for the atomizer solids residue particles in a complete single pass is 80%. This is reasonable because this particular air washer system had good inlet filtration media. [Pg.115]

The more obvious and understandable issue concerns the very high level of residual particles left by CMP. These particles essentially originate from the used slurries (Si02, AI2O3, Ce02) but also from the polished surface materials and to a lesser extent from the polishing equipment environment. The typical particle levels encountered depend greatly on the type of CMP... [Pg.184]

HF-based chemistry is particularly interesting due to its compatibility with all back-end metals and barriers. Unfortunately as the absolute values of tbe zeta potential in the A area of Fig. 13 are lower than in alkaline media, the removal mechanism is even more difficult. Indeed as seen in Fig. 19, the particle removal efficiency in the HF-HCl mixture is almost zero for actual alumina slurries. Very-high-power megasonics performed in a specific HF-compatible bath are absolutely necessary to obtain the same good residual particle level as with the scrubber. [Pg.205]

Finally, although the more direct way to remove slurries is still to use a scrubber, wet processes represent a cheaper alternative and achieve comparable residual particle levels on silicon oxides and silicon... [Pg.205]

Spray drying—Spray drying is applicable to substances that are soluble in a convenient solvent. This method involves atomizing a solution to form a mist. Larger particles are removed by impaction. The remaining flow is mixed with solvent-free air to permit evaporation of solvent from the droplets. Residue particles of the solute are left behind as the solvent evaporates. [Pg.16]

W. L. Tillman, Automated Gunshot Residue Particle Search and Characterisation, Journal of Forensic Sciences 32, no. 1 (January 1987) 62. [Pg.119]

It was also observed that the number of discharge residue particles on the firing hand decreased markedly as the bullet velocity increased. One possible explanation for this is that the greatly increased suction in the wake of the faster bullet causes more particles to be sucked out of the muzzle leaving fewer to exit from other vents and to be deposited on the hand. This... [Pg.124]

There is very limited information available concerning the total discharge residue particle population from the firing of ammunition. Available data suggest wide variations in total particle population from repeat tests using the same gun, ammunition from the same batch, the same sampling technique, and sampling promptly. [Pg.128]

Wolten and Nesbitt, On the Mechanism of Gunshot Residue Particle Formation, 533. [Pg.132]

M. Tassa, N. Adan, N. Zeldes, and Y. Leist, A Field Kit for Sampling Gunshot Residue Particles, Journal of Forensic Sciences 27, no. 3 (1982) 671. [Pg.133]

Discharge residue particles from starter pistol blanks were examined for comparison with discharge residue particles originating from firearms ammunition. Table 19.1 gives the starting pistol discharge residue particles classified according to their consistency with FDR particles. [Pg.146]

Individually, the starting pistol discharge residue particles could not be distinguished from FDR particles, by physical appearance, by size range, or by elemental composition, which includes the additional accompanying elements. ft is a reasonable assumption that discharge residue particles from... [Pg.146]

When the particles were considered as a group three distinct differences between firearm and starting pistol discharge residue particles were noted. [Pg.147]

The ratio of indicative to unique particles is markedly different from that of firearm discharge. From firearm residue casework statistics, based on cases with at least one particle in the unique category, the ratio of indicative to unique particles is approximately 35 1. For starting pistol discharge residue particles the overall ratio is in the region of 1 10. [Pg.147]

The work serves to illustrate the heterogeneous nature of firearm discharge residue particles and to clarify the types of particles detected. [Pg.151]

The classification scheme is based on discharge residue particles from modern primed brass-cased ball ammunition. It is only applied rigidly when no other information is available. When a gun, ammunition, spent cartridge case, or bullet is recovered, it can be examined to determine elemental composition and likely discharge residue particle composition. [Pg.154]

Discharge residue particles remaining in the launcher were also examined and the results are given in Table 20.7. [Pg.163]

This posed the question do potassium and sulfur always occur, often at high level in discharge residue particles from ammunition loaded with black powder In other words, from the presence and levels of potassium and sulfur can it be accurately predicted when black powder is used ... [Pg.166]

Discharge residue particles from black powder ammunition were then examined. Table 20.9 gives representative results. [Pg.166]

As antimony sulfide is widely used in primer compositions, sulfur is frequently present in discharge residue particles and can occur at major, minor, or trace level (see Table 19.5). Consequently the occurrence of sulfur at major level is not an accurate indicator of the use of black powder. The particles should be considered as a group and it is clear that the frequent occurrence of both potassium and sulfur at high level is strongly indicative of black powder. However, as can be seen from Table 20.9 the use of black powder does not necessarily yield overall high levels of potassium. Potassium does not normally occur at major level in FDR particles (see Table 19.5) and its presence at major level in any of the particles suggests the use of black powder. [Pg.166]

To clarify the situation it was decided to investigate the possibility that the antimony originated from the bullet. Discharge residue particles originating from ammunition with antimony-free primers and antimony-hardened bullets were examined for the presence of antimony. Results are given in Table 20.14. [Pg.179]

Antimony was detected in the residue particles on the suspect and it was known that the baton round does not have antimony in the primer. However, it was required to prove that there was no antimony in any part of a baton round. Analysis of the baton round revealed that the cartridge case was... [Pg.179]

In casework in which discharge residue particles were detected, and in which the ammunition involved is known to contain mercury, very few, if any, of the particles contained mercury. This has been noted over many years and in numerous cases. Possible reasons for this could be the volatility of mercury and its compounds, or decomposition of the mercury fulminate and the loss of mercury through amalgamation with zinc in the primer cup/car-tridge case. It is not uncommon, when firing old ammunition with mercury fulminate primers, for some of the cartridge cases to crack, due to embrittlement of the brass caused by mercury amalgamating with the zinc. [Pg.205]

This supports the proposition that anything present in a round of ammunition can make a contribution to the composition of the discharge residue particles. The presence of tin in any of the discharge particles is an indication that the primer contains mercury, the tin originating from the tinfoil disc used to seal mercury fulminate. (Tin is also present in some modern ammunition components, for example, Sellier Bellot, and it is present in some propellants.)... [Pg.208]

Indications are that the majority of the mercury is present in submicron particulate/vapor form and in large particulate form which is unlikely to be deposited on the firer. All these observations account for the scarcity of discharge residue particles containing mercury. The scarcity of mercury-containing discharge particles on the firer has been confirmed by other workers.201... [Pg.218]


See other pages where Residue particles is mentioned: [Pg.851]    [Pg.76]    [Pg.132]    [Pg.376]    [Pg.106]    [Pg.115]    [Pg.50]    [Pg.87]    [Pg.6]    [Pg.189]    [Pg.200]    [Pg.200]    [Pg.316]    [Pg.63]    [Pg.358]    [Pg.117]    [Pg.132]    [Pg.143]    [Pg.149]    [Pg.161]    [Pg.163]   
See also in sourсe #XX -- [ Pg.410 , Pg.482 ]




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