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1.  Reduction of Cogging Torque in Dual Rotor Permanent Magnet Generator for Direct Coupled Wind Energy Systems 
The Scientific World Journal  2014;2014:987062.
In wind energy systems employing permanent magnet generator, there is an imperative need to reduce the cogging torque for smooth and reliable cut in operation. In a permanent magnet generator, cogging torque is produced due to interaction of the rotor magnets with slots and teeth of the stator. This paper is a result of an ongoing research work that deals with various methods to reduce cogging torque in dual rotor radial flux permanent magnet generator (DRFPMG) for direct coupled stand alone wind energy systems (SAWES). Three methods were applied to reduce the cogging torque in DRFPMG. The methods were changing slot opening width, changing magnet pole arc width and shifting of slot openings. A combination of these three methods was applied to reduce the cogging torque to a level suitable for direct coupled SAWES. Both determination and reduction of cogging torque were carried out by finite element analysis (FEA) using MagNet Software. The cogging torque of DRFPMG has been reduced without major change in induced emf. A prototype of 1 kW, 120 rpm DRFPMG was fabricated and tested to validate the simulation results. The test results have good agreement with the simulation predictions.
doi:10.1155/2014/987062
PMCID: PMC4147280  PMID: 25202746
2.  Phytochemical analysis and evaluation of leaf and root parts of the medicinal herb, Hypochaeris radicata L. for in vitro antioxidant activities 
Objective
To analyse qualitative and quantitative phytochemical and evaluate in vitro antioxidant properties of various alcoholic and aqueous extracts of leaf and root parts of Hypochaeris radicata.
Methods
Preliminary phytochemical analysis for alkaloids, cardiac glycosides, flavonoids, glycosides, phenols, resins, saponins, steroids, tannins, terpenoids and triterpenoids and quantitative phytochemical analysis for alkaloids, total phenolics, total flavonoids, tannins, saponins and ascorbic acid were made by following standard procedures. In vitro antioxidant properties were evaluated by assessing DPPH•, NO• and ABTS•+, radical scavenging abilities and assaying the reducing power, β-carotene and antihemolytic activities by adapting standard methods.
Results
The quantitative phytochemical analysis of this species exhibited the presence of alkaloids, total phenolics, total flavonoids, tannins, saponins and ascorbic acid in considerable quantity. The in vitro antioxidant activity of the species, Hypochaeris radicata clearly demonstrated that both the leaf and root parts have prominent antioxidant properties.
Conclusions
From this study, it can be concluded that the species is effective in scavenging free radicals and has the potential to be a powerful antioxidant.
doi:10.12980/APJTB.4.2014C1030
PMCID: PMC4025295  PMID: 25183112
Hypochaeris radicata; Phytochemical analysis; In vitro antioxidant activities
3.  Exotic flora of some grasslands of Nilgiris with their medicinal uses 
Ancient Science of Life  2007;27(1):38-42.
In addition to the dominance of indigenous plant species, the grasslands of Nilgiris harbour a considerable number of exotic plants with sizeable number of individuals. In the present study in four major grasslands of Nilgiris, out of 12 exotic species present, 10 are recognized as medicinally important. The family, Asteraceae contributed a higher number of 6 medicinal species to the grassland community. The density of exotics in the studied grasslands is varied between 4 and 66/ha. In order to conserve the native species, the frequent harvesting of useful parts of exotics is suggested. In addition cultivation of these exotics in the degraded grasslands and other suitable habitats in Nilgiris may also reduce the pressure upon the native species and at the same time it will also meet the demand.
PMCID: PMC3330838  PMID: 22557258
Exotic medicinal plants; grasslands; Nilgiris
4.  In Vitro Organogenesis of Lycianthes bigeminata Bitter 
Ancient Science of Life  2007;26(4):18-23.
Lycianthes bigeminata Bitter (Solanaceae) is an important medicinal herb distributed in the sholas of Nilgiris and chiefly used for curing ulcer. It is reported that the species is present in the sholas with poor population size in comparison to other constituent species. Owing to the demand and subsequent exploitation, it is predicted that it may occupy still poor association in the sholas of Nilgiris in course of time. Hence in vitro regeneration through employing tissue culture technique is needed. The preliminary attempt in the present study reports that the MS medium supplemented with Benzyl Amino Purine (BAP) and Naphthalene Amino Acid (NAA) at 0.5 mg/l each, induced effective callus formation. However further studies on hardening is suggested to know the survivability of this species.
PMCID: PMC3330881  PMID: 22557245
Lycianthes bigeminata; callus; in vitro organogenesis
5.  Conservation of an endemic medicinal plant, Berberis tinctoria Lesch. In Nilgiris through micro propagation 
Ancient Science of Life  2004;24(1):22-26.
Berberis tinctoria Lesch. Is an endemic plant to high hills of Nilgiris having lot of medicinal properties. For its better conservation through mass multiplication, attempts have been made to standardize tissue culture technology. The results of the study exhibited that the basal medium containing BAP and NAA each at 0.5 mg/1 was found to be the optimum for callus formation. Shoot proliferation was highly effective in the basal medium supplemented with BAP at 0.5 mg/1. The root initiation was maximum in the basal medium containing the NAA at 1.0 mg/1 and the plantlet establishment was successful in the hardening medium composed by vermiculite and soil in the ration of 1:1.
PMCID: PMC3330911  PMID: 22557146
6.  MODERN PROPAGATION TECHNIQUES- A CONSERVAION TOOL FOR CERTAIN ENDEMIC MEDICINAL PLANTS IN NILGIRI BIOSPHERE RESERVE 
Ancient Science of Life  2002;21(3):170-172.
There plant species of medicinal and vegatational fire break importance such as Berberis tinctoria, Elaegnus kologa and Rhodomyrtus tomentosa were identified in Nilgiri Biosphere Reserve and their eco-physiological behaviors were analysed. The study revealed that generally all the there species were having shorter period of seed dormacy, poor viability of seeds and higher mortality of saplings. These poor eco-physiological features are the major factors for their limited distribution, lesser population and weaker establishment. Hence to overcome these factors the modern reproductive strategies like tissue culture techniques are suggested.
PMCID: PMC3331040  PMID: 22557048
7.  Fire Control – A Conservation Tool for certain Medical Plants in Grass Hills Ecosystem, The Western Ghats 
Ancient Science of Life  2001;20(4):89-92.
Grass Hills ecosystem lies in Anaimalais. The western ghats possesses rich biodiversity, The annual summer fire, an integral part of this ecosystem, promotes the ecological status of certain perennial grasses including the dominant grass. Chrysopogon zeylanicus Thw. On the other hand, some medicinal plants Viz., Impatiens tomentosa Heyne, Drosera peltata Sm Osbeckia parviflora Arn., Emilia sonchifolia Dc. Lecanthus penduncularis Wedd. And Lobelia nicotianifolia Heyne were identiflora Arn. Emilia sonchifolia Dc. Lecanthus penduncularis wedd and lobelia nicotianifolia Heyne were identified as fire threatened species and it has been observed that their sociological attributes were hampered severely by fire. Hence, the conservation of such species is needed through effective fire control measures.
PMCID: PMC3336411  PMID: 22557019

Results 1-7 (7)