Drying temperature dependence

To constant weight at <35-105°C (actual drying temperature dependent on analytical requirements). 

Removal of water from gases may be by physical or chemical means, and is commonly by adsorption on to a drying agent in a low-temperature trap. The effectiveness of drying agents depends on the vapour pressure of the hydrated compound - the lower the vapour pressure the less the remaining moisture in the gas. 

Other materials subject to self-heating (depending upon composition, method of drying, temperature, moisture content)... 

Shown in Figure 15.5 are the temperature dependent XRD data for the 5% Pd-1% Sn catalyst. As noted above, the scans were offset in the order that they were obtained (the Time axis, as shown, is the scan sequence number and not the actual temperature). The inset of Figure 15.5 illustrates the temperature profile for the scan sequence. The first scan was obtained at room temperature, at which time hydrogen was introduced into the chamber at 500 Torr. The temperature was then ramped in 10°C increments to 160°C and XRD scans were taken after each increment. The sample was held at 160°C for I/2 hour, and then cooled to room temperature. After I/2 hour at room temperature, the sample was purged with dry nitrogen. 

Therefore, freeze-drying should be carried out at the highest allowable product temperature that maintains the appropriate attributes of a freeze-dried product. This temperature depends on the nature of the formulation. Process development and validation requires characterizing the physical state of the solute, or solutes, that result from the freezing process and identifying a maximum allowable product temperature for the primary drying process [20,21]. 

Bv employing a soluble cationic polymer as the solution electrolyte polymer films can be sterical ly blocked from reducing beyond the formal zero valent form. In the zero-valent form the polymer is an ohmic conductor both in solution and dry. A model has been proposed which describes the conductivity of the polymer and in part accounts for its ohmic nature and semi conductor-1 ike temperature dependence. 

Part 1. Kinetics and Energetics of Dry Oxidation. The simplest approach to data analysis is to assume that only a single class of oxidation reactions is important and to make the related assumption that the temperature dependence of the single rate constant k can be represented by an Arrhenius equation. In this way we obtain... 

The chloroimide decomposed violently on a drying tray at 60°C [1], and a bottle accidentally heated to 50°C exploded [2], Decomposition of the heated solid occurs after a temperature-dependent induction period. Unheated material eventually exploded after storage at ambient temperature [3],... 

Conditions to be met in oven drying enamels depend also on the composition of the binder. Paint systems containing melamine-formaldehyde or urea-formaldehyde resins, for instance, harden by polycondensation with other resins, such as epoxy resins, short-oil alkyd or acrylic resins at elevated temperatures. Baking is carried out at temperatures between 100 and almost 200°C and may last from a few minutes to more than an horn. A general trend towards energy conservation has shifted public attention towards binders which require low baking temperatures. 

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