SEDEX system

Compounds studied by ARC include styrene (174), o-nitroaniline (169), di-if-butyl) peroxide (171), and substances employed in the synthesis of explosives, detergents, bleaches, adhesives, fertilizers, resins, plastics, and many others. 

A comparison has been made of the evaluation of thermal hazards by DTA. DSC. Dewar Jests, and ARC (175). 

The SEDEX system (Sensitive Detector of EXothermic processes) was developed by Hakl (176-178) for investigating the thermal decomposition of compounds undergoing exothermic processes. It features (1) a high sensitivity (2) a mode of operation conformable to plant conditions (3) economy, for example, low cost of apparatus, simultaneous measurements, reliable data, and so on and (4) a simple way to operate and interpret the results. 

A comparison of SEDEX with other methods is given in Table 11.12. The SEDEX temperature is always lower than any of the other methods listed. The Sikarex is an adiabatic calorimeter developed by Sandoz. 

Substance Dynamic Decomposition Test DSC Sikarex Sedex 

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The Sikarex safety calorimeter system and its application to determine the course of adiabatic self-heating processes, starting temperatures for self-heating reactions, time to explosion, kinetic data, and simulation of real processes, are discussed with examples [1], The Sedex (sensitive detection of exothermic processes) calorimeter uses a special oven to heat a variety of containers with sophisticated control and detection equipment, which permits several samples to be examined simultaneously [2]. The bench-scale heat-flow calorimeter is designed to provide data specifically oriented towards processing safety requirements, and a new computerised design... 

In Part 2 of the PCB story, we introduced the exchange between the water column and the surface sediments in exactly the same way as we describe air/water exchange. That is, we used an exchange velocity, vsedex, or the corresponding exchange rate, ksedex (Table 23.6). Since at this stage the sediment concentration was treated as an external parameter (like the concentration in the air, Ca), this model refinement is not meant to produce new concentrations. Rather we wanted to find out how much the sediment-water interaction would contribute to the total elimination rate of the PCBs from the lake and how it would affect the time to steady-state of the system. As shown in Table 23.6, the contribution of sedex to the total rate is about 20% for both congeners. Furthermore, it turned out that diffusion between the lake and the sediment pore water was much more important than sediment resuspension and reequilibration, at least for the specific assumptions made to describe the physics and sorption equilibria at the sediment surface. 

Analysis of Tween 80 was performed using a Hewlett Packard 1100 series HPLC equipped with a Sedex 55 Evaporative Light Scattering Detector (ELSD). The mobile phase consisted of 80% acetonitrile and 20% water. Duplicate injections (5 pL) of each sample were evaluated by HPLC. Potassium iodide, used for the 1-D column and 2-D box tracer studies, was analyzed with a continuous flow Isco V4 variable UV wavelength absorbance detector equipped with an EZChrom Chromatography data acquisition system. 

Split eluent from the HPLC system 1 5 to the mass spectrometer and a Sedex 55 (S.E.D.E.R.E., AlfortvUle Cedex, France) evaporative light scattering detector. 

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