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A comprehensive approach to quantify more accurately the physical phenomena leading to blooming effects on infrared sensors is proposed. Laser dazzling effects on mid-infrared HgCdTe focal-plane-array are investigated thanks to the use of an experimental breadboard. This dedicated breadboard is capable of delivering intense laser spots on focal-planearrays with accurate control of laser spot diameter, position, power and pulse time sequence. The main subsystems of this experimental bench are described, laser sources, focusing optics, power control device and opto-electronic synchronization. HgCdTe focal-plane-array dazzling experiments are then analyzed. The main parameters affecting blooming are varied and the impact of spatial, time and energy characteristics on the resulting dazzled image are assessed.

In buffered water:methanol media, the pKavalues of acid-base equilibria involved in the protonation of substituted quinolines are determined by UV-visible absorption spectrometry. The observed behavior depends on the nature of R2: the N—CH3derivatives exist as quinoline, the N—H derivatives as 4-iminoquinoline tautomers. The iminoquinoline zwitterionic species present at physiological pH may have high receptor affinity. A linear relationship between pKaof the endocyclic nitrogen and log IC50is discussed.

L'acide β-bromopyruvique 1 et son ester éthylique 2 subissent en solutions aqueuse ou hydro-alcoolique, sur cathode de mercure, une hydrogénolyse de la liaison carbone-brome. En solution aqueuse, la réduction est tributaire de la déshydratation antécédente du carbonyle et les courants cathodiques sont faibles. En milieu hydro-alcoolique, le phénoméne se complique du fait de l'adsorption à l'électrode à goutte de l'un des produits de la réduction: les ions bromures.