A potential—Time relationship for the reversible re-oxidation of an insoluble product by current reversal chronopotentiometry

An equation is presented for the potential—time dependence for the reversible re-oxidation of an insoluble product using current reversal chronopotentiometry with an inert electrode. The relationship presented accounts for unequal forward and reverse current densities. Experimental verification is presented with results from a study of silver and lead ions in molten LiCl?KCl eutectic at 710 K using a glassy carbon working electrode.     

The enantioselective conversion of ortho-substituted benzoic acids to chiral cyclohexane derivatives

The diastereoselectivity of reductive methylation of 1a–1c to give 2a–2c and 11 to give 12 is 260:1 and >99:1, respectively.     

10 watt CW, 5000 h lifetime monolithic AlGaAs laser diode arrays

1 cm-wide monolithic laser diode arrays emitting at about 810 nm with a 3 mm total active aperture width have been life-tested at 10 W constant power at 20 degrees C heat-sink temperature. One array has been operated for over 3000 h and has a projected lifetime in excess of 5000 h.<>     

Identification of 2-(2'-octenyl) succinic acid in urine

2-(2'-octenyl)succinic acid has been identified in urine samples from children investigated for a possible inherited metabolic disease. Its structural identification has been achieved by gas chromatography/mass spectrometry using both electron ionization and chemical ionization and by tandem mass spectrometry (MS/MS) using fast-atom bombardment and high-resolution electron-ionization analyses of the molecular ion in a complex biological matrix. The localization of the double bond was obtained by interpretation of a unexpected rearrangement reaction occurring after dimethyl disulfide derivatization.     

High-power and high-efficiency phased array lasers grown by a two-step metalorganic chemical vapour deposition

Phased array lasers which emit 1.3 W CW output were fabricated using a two-step metalorganic chemical vapour deposition process were developed. The differential efliciency at 100 mW is 78% and the total efficiency at the catastrophic limit is 39%.     

A pathological case in the reduction of linear programs

This note discusses a pathological case which may arise when a reduction procedure is used to detect implied ‘free’ variables in linear programs. This is the possibility of a spurious unbounded condition. We detail the cause of this anomaly and discuss algorithmic remedies, giving computational experience.