Deposition modifier

Where additives are employed, they are known as slag modifiers or deposit modifiers and are designed to raise the MP of the oxides and slag formations, thus resulting in less sticky deposits with a reduced tendency to adhere to walls and tubes. 

Fig. 1. Regional geological map of Chehelkureh polymetallic ore deposit (modified from Valeh Saeedi 1989).

Fig 1. Regional geology map of the Victoria Lake Supergroup showing the Tulks Volcanic Belt occurring from the south west to the north central part of the map area. Also shown are the other volcanogenic massive sulfide deposits (modified from Hinchey 2007). 

Fig. 1. Geology map of the Lac Turgeon Granite, Quebec. The Main Double S zone is indicated, along with several U occurrences, and the Grandroy deposit (modified from Cooper 1957).

Only a few additives have been proposed as general-purpose deposit modifiers or preventers. Boron compounds have already been mentioned (46). Use of metal chelates of pentadione (PD) as a combustion catalyst, said to remove deposits and keep clean combustion-chamber surfaces, was reported in 1949 (7) and was disclosed in patents as far back as 1937. More work on octane-requirement increase depressants may be expected. 

Engineering of reaction and Chemical vapor deposition Modified chemical vapor deposition... 

T.C. Chiang, J.C. Chan, and C.S. Tan, Alkylation of Toluene with Isopropyl Alcohol over Chemical Liquid Deposition Modified HZSM-5 under Atmospheric and Supercritical Operations. Ind. Eng. Chem. Res., 2003, 42, 1334-1340. 

Fig. 15. Palaeogeographical and palaeoclimatic imprints on the eogenetic fluid composition and the distribution of early carbonate cements in the Serraria deposits. Modified from Garcia (1992).

The SEM micrographs shown in Figure 3 provide evidence for the proposed prevention of calcification by citrate anions. It can be seen that the calcium phosphate deposits formed on PHEMA in the presence of citric acid are much lower in amount and smaller in size (Figure 3C). In other words, under the action of citrate anions, the extent of the deposition of calcium phosphates was significantly reduced and the nature of the deposits modified. This is confirmed by the veiy low calcium contents of the calcium phosphate deposits over the whole range of calcification times (see Figure 4), as determined by XPS. It should be mentioned here that after 5 weeks of calcification time, at least one layer of calcium phosphate (with a thickness of 0.4 pm (33)) was deposited on the surface of PHEMA containing no citric acid. Thus, it is anticipated that the calcium content of the calcium phosphate deposits tends to plateau after 5 weeks in SBF solution. 

Vertical profiles, by themselves, are generally insufficient to identify sources or to rule out postdepositional rearrangement. Simple deposition, for example, cannot be credibly distinguished from deposition modified by mixing or remobilization. 

Figure 11. Sulfur isotope values of sulfide minerals from selected seafloor hydro-thermal deposits. Modified from Herzig et al. (1998) with additional data from Table 1.

Fig. 14.18 Upper panel illustrates dissolved chloride concentration in pore waters collected from the summit of Hydrate Ridge during ODP leg 204 (Sites 1249, 1250, from Torres et al. 2004) and from a gravity core recovered from this area during RV SONNE expedition SO-143 (Haeckel et al. 2004). These data (panels A-C) indicate that hydrate is forming at very fast rates, so as to maintain the extremely high chloride values. Furthermore, to sustain the rapid formation rates, Torres et al. (2004) and Haeckel et al. (2004) show that methane must be supplied in the gas phase, as illustrated by the cartoon in panel. Methane solubility in seawater is too low for aqueous transport to deliver sufficient methane to form the observed hydrate deposits. D. Mass balance calculations based on a simple box model (E) indicate that the massive deposits recovered from the Hydrate Ridge summit probably formed in a period of the order of lOO s to lOOO s of years, highlighting the dynamic nature of these near-surface deposits (modified from Torres et al. 2004 and Haeckel et al. 2004).

For this reason limestone is not often used in conjunction with oil combustion [Radway and Hoffman 1987]. The presence of high ash in coals however, tends to modify the sulphate deposition so that it is possible to use limestone as a deposit modifier in the combustion of certain coals. 

Figure 1. Paleolatitudes of 72 major phosphate deposits (modified from Slansky 1986).

Figure 9 °Pb excess over in the upper thermocline from several stations of the Pacific. This excess resulfs from its atmospheric deposition. (Modified from Nozaki et at, 1980.)...

V-680 System modification Mist carryover with salt deposition Modify post-V-680 trap... 

Doping or increased substrate tanperature during the deposition modified the density of localized states in a way that moved the conduction path closa to the Fermi levd fixed with r pect to the valence band. 

Fig. 2.7 Location of the Bayan Obo deposit. Modified after Drew et al. (1990) and Wikipedia (2014)...

Fig. 5 A quantitative comparison of the compact deposit modified electrode response to increasing nitrate concentration under silent and sonicated conditions. The response obtained at an intact porous, copper-modified electrode under silent conditions is also included.

LSCF Lhq 2SrQ gCog 4 Fgq g03 g Modified Fiollow fibre Ag-deposited modified Fiollow fibre Pt-deposited modified Fiollow fibre Flat disc 1... 

Fig. 3.7 Schematic representation of a LDH-ABTS laccase electrode b SWCNT- LDH-ABTS laccase mixed coating and c two layers configuration based on an inner SWCNT deposit modified by a LDH-ABTS laccase coating...

Fig. 3.8 Power density of laccase-glucose oxidase biofuel cell as a function of cell potential in air-saturated 0.1 M phosphate buffer (pH 6.0) containing 5 mM glucose for biofuel cell based on a LDH-ABTS laccase biocathode and b two layers configuration (SWCNT deposit modified by a LDH-ABTS laccase coating) biocathode...

Idriss, I.M. Sun, J.I. 1992. Shake91, A Computer Program for Conducting Equivalent Linear Seismic Response Analysis of Horizontally Layered Soil Deposits Modified based on tbe original SHAKE program Published in December 1972 by Schnabel, Lysmer and Seed. 

MLCT (metal-to-ligand charge transfer), 474 MOD. See metal organic deposition modified Pechini s method chelation aspects, 62, 63 complexation aspects, 63, 64 defined, 61 pH dependence, 64 precipitation aspects, 63, 64 use of, 79... 

The current cell employs vertical DSA coated titanium anodes, vertical cathodes of woven wire mesh bolted to a perforated steel backplate, and a vacuum-deposited modified asbestos diaphragm. A single bipolar element may have 100 m of both anode and cathode active area. The anode of one element is connected to the cathode of the next by copper spring clips. This connection is immersed in the cell liquor during operation. Figures 33 B and 34 show these internal cell parts. 

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