A Modulation Technique for Sensorless Control of Switched Reluctance Motor

The switched reluctance motor (SRM) uniquely bears several merits with respect to other motor configurations. Especially, the construction of the rotor is simple in the sense that it neither contains copper not contains permanent magnets. Because of this construction, likelihood of rotor’s failure is less than the other motor configurations. This makes this motor more suitable for harsh environments. On the flip side, this motor cannot directly operate with AC or DC power source and needs electronic commutation. For commutation, the information on instantaneous orientation of the rotor is essential. Since inclusion of appropriate sensor adds to the cost and complexity of the system, sensor-less commutation of SRM gained interest among the researchers and has been studied extensively in literature. The techniques for sensorless control of SRM can be broadly classified into Active phase and Idle phase techniques. Idle phase techniques are generally believed to be not suitable for high speed operation beause of tail current in a phase, i.e., because of inductive nature of the phase, it takes time for flow of current to stop. This paper proposes a novel idle phase technique that is conducive for high speed operation of switched reluctance motor.

A facile synthesis of 1,3-diphenyl-4-arylspiro[pyrazoline-5, 3′-flavan-4′-one]

Synthesis of a series of novel 1,3-diphenyl-4-arylspiro[pyrazoline–5,3′-flavan-4′-ones] has been accomplished in good yields by the regioselective 1,3-dipolar cycloaddition of diphenylnitrilimine with (E) 3-benzylideneflavan-4-ones.

Field evaluation of Bacillus cereus VCRC B540 for mosquitocidal activity - A new report

A major challenge to control the vector mosquitoes and their diseases. The discovery of bacteria like Bacillus sphaericus Neide (Bs) and B. thuringiensis serovar israelensis de Barjac (Bti), which are highly toxic to dipterans larvae, have opened up the possibility of their use as potential bio-larvicides in mosquito eradication programmes the world over. These bacteria have some important advantages over conventional insecticides in mosquito control operations, besides being safe for non-target organisms including human beings. But, the recent researchers have been reported mosquito resistant against these biological agents. Bacillus cereus VCRC B540 is one of the most potential bio-pesticides which were isolated from the gut contents of the marine fish (Lutjanuas sanguineus) collected in east coastal zone of the Bay of Bengal (Union Territory of Pondicherry, India) to control Culex, Anopheles and followed by Aedes species. The isolated strain was confirmed as Bacillus cereus based on the biochemical characteristics and 16S rDNA gene sequence. The larvicidal activity of B. cereus VCRC B540 was further characterized.

Limb-girdle muscular dystrophy with obesity for elective cesarean section: Anesthetic management and brief review of the literature

Limb-girdle muscular dystrophy (LGMD) is an autosomal recessive disorder in which the pelvic or shoulder girdle musculature is predominantly or primarily involved. We report the management of a 27-year-old primigravida with LGMD associated with obesity posted for elective cesarean section. She was successfully managed with epidural anesthesia assisted with noninvasive positive pressure ventilation. She had an uncomplicated intra- and post-operative course.

Preparation and Thermo-Physical Properties of Fe2O3-Propylene Glycol Nanofluids

Iron oxide (Fe2O3) nanoparticles were prepared from ferric chloride and ferrous sulphate by precipitation reaction. Fe2O3-propylene glycol nanofluid was prepared by dispersing Fe2O3 nanoparticles in propylene glycol through stirred bead milling, shear homogenization and probe ultrasonication. The nanofluid was characterized through measurement of viscosity, particle size distribution and thermal conductivity. The interactions between Fe2O3 nanoparticles and propylene glycol on the nanoparticle surfaces lead to reduction in viscosity, the magnitude of which increases with nanoparticle concentration (0-2 vol%) at room temperature. The thermal conductivity enhancement for 2 vol% nanofluid was about 21% at room temperature, with liquid layering being the major contributor for thermal conductivity enhancement.