Bulk temperature

Although they may be completely soluble in the lower temperature bulk water, these compounds (eg, calcium carbonate, calcium phosphate, and magnesium siUcate) supersaturate in the higher temperature water adjacent to the heat-transfer surface and precipitate on the surface. 

High-solids, two-component, clear, aliphatic, polyurea coating, preparation of, 252-253 High-temperature annealing, 220 High-temperature bulk polyesterifications, 61-74... 

High-temperature bulk reactions, 63 High-temperature condensation, in cresolic medium, 302... 

The magnitude of the peak current, /p, in a cyclic voltammogram is a function of the temperature, bulk concentration, Canaiyte. electrode area. A, the number of electrons transferred, n, the diffusion coefficient, D, and the speed at which the potential is scanned, v, according to the Randles-Sev lk equation, as follows ... 

At ordinary temperatures, bulk nickel in compact form has no perceptible reactivity with air or water. However, in finely-divided state, the metal reacts... 

Although these low temperature bulk degradation experiments provide insight into the detailed mechanism of AP decomposition, it is doubtful whether kinetic rates obtained from such experiments can be extrapolated over many orders of 10 to the temperatures typically encountered at the propellant surface, especially since degradation in bulk is not the same as degradation at the surface of the sample. 

The mechanism of high temperature bulk polymerisation of NCA s is still obscure. It was suggested that the reaction involves the isomerisation of the anhydride into isocyanate, viz. 

Under the present oxygen treatment conditions, treated WC did not show any change in bulk structure as seen by XRD when the treatment temperature was below 773 K. At 773 K, bulk oxide was formed and the sample was inactive for -hexane-H2 reactions. Hence, four WC samples were compared fresh WC (WC/fresh) and WC treated in 02 at RT, 473 K, and 673 K (denoted by WC/treatment temperature). Bulk oxidation occurred at much lower temperatures for Mo2C and thus the maximum temperature of the oxygen treatment was 473 K (Mo2C/473). 

Table 3. Intrinsic Viscosity vs. Temperature Bulk Polymerization with 0.008 Molar Benzoyl Peroxide...

Figure 1. The room temperature bulk ionic conductivity, along z, of KTP crystals as a function of the reciprocal of their midpoint growth temperatures., Philips flux , DuPont flux O Airtron high temperature hydrothermal , Airtron low temperature hydrothermal.

Initial rotation of H2O before the absorption of the photon gradually destroys the preferential population of A A") with the consequence that the 2U(A") / 2Il(A ) ratio slowly converges towards the statistical limit of 1 as the temperature of H2O increases. It is exactly 1 for the photodissociation in the room-temperature bulk (Figure 11.5). More about... 

Product temperature Bulk/tapped density Moisture content... 

Figure 8. Scaling of areal density (AD) with anisotropy energy density Ku using room temperature bulk data from Table 2 and elongated cubes with constant grain aspect ratio 5/Dp = 4 (case d) (the dashed line is a linear fit of the data to the power one).

Carbon-halogen groups are well known to exist for fluorine, chlorine and bromine. These groups can be attached by redox reactions involving the halogen elements cither in aqueous solution or in the gas phase. At elevated temperatures bulk reactions occur under intercalation and eventually under formation of bulk covalent carbon-halogen materials (CF1.1 solid, CCU... 

Several oxides with perovskite related stmctures can also be intercalated with oxygen ions by an electrochemical method. The oxide Sr2Fe20s with the brownmillerite stmcture has been electrochemically oxidized to SrFeOs. The reaction was carried out by controlled potential electrolysis at a potential below that for oxygen evolution in 1 M aqueous KOH at room temperature. Bulk oxidation was confirmed by Mossbauer spectroscopy and X-ray difflaction. Similar results have been obtained for electrochemical oxidation... 

Baxter E. F. and DePaolo D. J. (2002a) Field measurement of high temperature bulk reaction rates I. Theory and technique. Am. J. Sci. 302, 442-464. 

OH(t) = 0) rotational distributions deriving from complexes dilfer from their room temperature bulk counterparts when using the same photolysis wavelength. The qualitative shapes of the rotational distributions are not the same, with complexes showing decidedly more low-J excitation than bulk samples. Examples are shown for the cases of C02-HBr, CO2-H2S, and CO2-HI in Figures 19-21, respectively. Nothing unusual was noted in the spin-orbit or A-doublet occupancies. 

Figure 20. OHu = 0 rotational distributions for the H2S/CO2 system (193nm photolysis) obtained (a) under room temperature bulk conditions, (b) under low temperature bulk conditions, and (c) with CO2-H2S complexes. Note the similarity between (a) and (b). There were no differences of consequence associated with OH spin-orbit excitation or the A-doublets.

A small amount of material deposited on a pure host crystal will always be metastable at non-zero temperatures, since the gain in entropy by dissolving into the bulk, which is roughly AS=k a NJN, where Nb and N, are the number of sites in the bulk and at the surface, respectively, will drive the deposited material away from the surface. However, as has already been mentioned, near room temperature bulk diffusion in a metal is extremely slow, and a local equilibrium is usually established in the surface region. 

The computer program simulates the batch polymerization of styrene and has been applied to the relatively low temperature peroxide-initiated polymerization typical of suspension processes and to higher temperature bulk, thermal conditions. It has been useful in the design of new suspension processes and for more general process analysis. 

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