Detonation properties of tetranitromethane–methanol mixture

The propagation of detonations through several fuel–air mixtures with spatially varying fuel concentrations is examined numerically. The detonations propagate through two-dimensional channels, inside of which the gradient of mixture composition is oriented normal to the direction of propagation. The simulations are performed using a two-component, single-step reaction model calibrated so that one-dimensional detonation properties of model low- and high-activation-energy mixtures are similar to those observed in a typical hydrocarbon–air mixture. In the low-activation-energy mixture, the reaction zone structure is complex, consisting of curved fuel-lean and fuel-rich detonations near the line of stoichiometry that transition to decoupled shocks and turbulent deflagrations near the channel walls where the mixture is extremely fuel-lean or fuel-rich. Reactants that are not consumed by the leading detonation combine downstream and burn in a diffusion flame. Detonation cells produced by the unstable reaction front vary in size across the channel, growing larger away from the line of stoichiometry. As the size of the channel decreases relative to the size of a detonation cell, the effect of the mixture composition gradient is lessened and cells of similar sizes form. In the high-activation-energy mixture, detonations propagate more slowly as the magnitude of the mixture composition gradient is increased and can be quenched in a large enough gradient.

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Ultrasonic Determinations of Chromium Soaps in a Benzene-Methanol Mixture / Ultraschallmessungen an Chromseifen in Benzol-Methanol-Mischungen

Tenside Surfactants Detergents ◽

10.1515/tsd-1996-330119 ◽

1996 ◽

Vol 33 (1) ◽

pp. 69-72

Author(s):

K.-N. Mehrotra ◽

M. Jain

Keyword(s):

Methanol Mixture

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Evaluations about the physico-chemical stability of docetaxel and irinotecan pre-diluted and diluted solutions: pharmaco-economic perspectives

Drugs and Therapy Studies ◽

10.4081/dts.2013.e6 ◽

2013 ◽

Vol 3 (1) ◽

pp. 6 ◽

Cited By ~ 1

Author(s):

Mariarita Laforgia ◽

Anna Elisa Quatrale ◽

Nicola A. Colabufo ◽

Amalia Azzariti ◽

Angelo Paradiso ◽

...

Keyword(s):

Chemical Stability ◽

Mobile Phase ◽

Ammonium Acetate ◽

Physical Stability ◽

Experimental Conditions ◽

Phase Gradient ◽

Methanol Mixture ◽

Physico Chemical ◽

Starting Point ◽

Economic Perspectives

Several clinically used anticancer drugs are well-known as far as their pharmacologic properties are concerned, but scarcely ever the interest towards their physico-chemical characteristics in solution led to practical acknowledgement in their management. Thanks to the Units for Centralized Anticancer Drug Handling, the importance to evaluate the concentration of saturation (physical stability) or the possible transformations undergone by a drug in solution (chemical stability) has become the starting point for avoiding useless wasting drugs and economic resources. By HPLC experiments we have demonstrated that the solutions of two drugs, docetaxel and irinotecan, are particularly stable at different concentrations and times of analyses in our experimental conditions. The best mobile phase for docetaxel was water/methanol/acetonitrile in 42/32/26 volumetric ratio: for halving concentrations (0.72-0.36-0.18-0.09 mg/mL) in NaCl 0.9%, the highest value gave a six-day and the three lower concentrations a fourteen-day stability, when storage occurred at room temperature and light protected. Elution of irinotecan was possible through an analysis in mobile phase gradient: at t0 a 20% ammonium acetate 10 mM and 80% methanol mixture, and after 5 min, a 80% ammonium acetate 10 mM and 20% methanol mixture. The physico-chemical stability was showed for five days, for any concentration of analysis when storage occurred at 2-8°C and light protected.

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