Dislocation etch pits in anhydrous diglycine sulfate

New dislocation etchants for anhydrous diglycine sulfate single crystals have been developed and the etching results are reported. Dichloroacetic acid, glacitel acetic acid and their mixtures work as dislocation etchants on the cleavage plane of the crystal. Morphology of the etch pits was found to vary with the etchant composition.     

Thermal Etching on Calcite Cleavages

Thermal etch pits are observed on calcite cleavages at very small range of temperatures in atmosphere. Different characteristics such as nonmovement of cleavage lines and dislocations, thermal percussion by gas molecules, are observed in thermal etching. It is found that chemical and thermal etching are not the same process for calcite cleavage etching. The origin of thermal etch pits is not at dislocations intersecting the cleavage surfaces.     

Effect of electrode annealing on the aging characteristics of thin metal films

The resistance of thin films of silver, copper, indium and aluminium deposited onto clean glass substrates were measured using annealed and unannealed films of chromium-copper alloy as electrodes. The percentage variation in resistance for different metal films differ with annealed and unannealed electrodes. Formation of oxide and alloying at the electrodefilm junction are discussed taking into account the observed variations in resistance. Microscopic observations are also made of the film-electrode junctions.     

On growth and morphological studies of TGS single crystals

The effect of various growth parameters; seed morphology, growth-temperature and pH of the mother solution on the growth of TGS single crystals is studied. The effect of these variables on the crystal morphology and perfection is reported. It is shown that; (i) The crystal quality is much dependent on the seed and the growth temperature and (ii) the pH-control is a simple and an effective method for obtaining TGS crystals of required morphology.     

Degradation process in organic thin film devices fabricated using P3HT

The stability of regioregular poly(3-hexylthiophene 2,5-diyl) (P3HT) thin films sandwiched between indium tin oxide (ITO) and aluminium (Al) electrodes have been investigated under normal environmental conditions (25°C and RH∼45–50%). Electrical and optical properties of ITO/P3HT/Al devices have been studied over a period of 30 days. Mobility μ of the order of 10⁻⁴ cm²/V-s has been obtained from the V ² law in the as-deposited P3HT films. Scanning electron microscopy (SEM) investigations show blistering of Al contacts in devices with a poly(3,4-ethylenedioxythiophene) (PEDOT) interlayer on application of voltage whereas no blistering is seen in devices without PEDOT. The results have been explained in terms of trap generation and propagation and the moisture-absorbing nature of PEDOT.      

Michael reaction of ketones and β-nitrostyrenes catalyzed by camphor-10-sulfonamide-based prolinamide

Novel camphor sulfonamide based organocatalysts were evaluated for their catalytic activity in the Michael reaction of ketones with nitroolefins. Reaction of ketones with β-nitrostyrenes in the presence of 20 mol % organocatalyst 1a and benzoic acid under solvent-free conditions at 0 °C provided the desired Michael adducts with high chemical yields (up to 97%) and excellent stereoselectivities (>99:1).     

Two-echelon location routing synchronized with production schedules and time windows

Central European Journal of Operations Research - In this paper we study a problem that arose while planning the delivery of perishable goods, such as newspapers or foodstuff, in urban areas. The...