Volume 13, Issue 3, 2013 July-September

Volume 13, No 3 Pages:
2013 July-September Articles: 5

Thermoluminescence (TL) characteristics of Ba1-xCaxSO4:Eu nanophosphor

TL phosphor based on Ba1−x CaxSO4:Eu (1 at %) (0 < x < 1) was prepared using the chemical co-precipitation technique. XRD shows orthorhombic structure. It was found that the TL sensitivity of the material changes on varying the concentration of Ca and maximum sensitivity is found for Ba0.98Ca0.01SO4:Eu.01. Moreover, the phosphor had constant glow curve shape over a dose range of 100-1000Gy. The dose response is linear/sub-linear over the dose range 100-500 Gy, above which TL sensitivity saturates.

Ecological aspects of roosting habits of frugivorous bat, Rousettus leschenaulti in Ṭawi Wildlife Sanctuary, Mizoram

The roosting site of the frugivorous bat, Rousettus leschenaulti of the Ṭawi Wildlife Sanctuary was surveyed and the population was determined. The abiotic parameters such as temperature, relative humidity, light intensity, roosting area, the structural details of roosting site, etc. as well as the biotic parameters such as the composition of age and sex, roosting pattern, seasonal variation in the roosting behaviour, etc. were determined. The roosting site, RS was occupied by a colony of over 1215 individuals. The variation in light intensity (0.2–0.8 lux), temperature (28 ± 0.2oC) and relative humidity (94 ± 1%) was least in this roosting site because of the closed and insulated nature of the roost. This is a specious and dark roosting site. These bats roosted in four types of clusters namely mixed-sex adults, mixed-sex sub-adults, pregnant females with lactating mothers, and the mixed-sex old individuals. The formation of clusters was based on the sex, age and reproductive status of individuals. The sex-bias favoured females.

Geospatial planning for improved land use system in Saiha District, Mizoram, India

Scientific inputs and analysis of land and water resources are important units for effective land use programmes to optimize the use of available resources. The success of these plans relies on the careful assessment of qualitative and quantitative information derived from the analyses. Geospatial planning has emerged as an effective and reliable platform to assist in this process of developmental planning even at the grassroot level. In this context, the present study incorporates remote sensing and GIS techniques to map the natural resources and to formulate viable land and water resource management plans for improved land use system which will be more sustainable and productive. The study was done in the southern part of Mizoram, i.e. Saiha district wherein an integrated approach of land use planning had been derived that encompassed every aspect of land, water and socio-economic component of the district. Integration of these components in a GIS system helped in formulation of different suitable land use scenarios with economic and biophysical benefits. The result of this study presents maps with constructive options for land and water resource developments in the study area. This information will be very useful for decision makers to plan according to the schemes and resources available at hand.

Phase velocity of harmonic waves in monoclinic anisotropic medium

The problem of phase velocity of plane waves in monoclinic anisotropic medium was investigated. The phase velocity of Quasi-nature elastic waves was obtained analytically and numerically for a particular model. It was observed that the phase velocity of elastic waves is functions of the angle of propagation, elastic constants and density of the medium. These phase velocities were computed numerically for a particular model.

Strategies for large-scale production of commercially important banana varieties of Mizoram, India, using plant tissue culture technique

The technique of plant tissue culture has been well accepted and applied in the mass propagation of planting materials in various crops and plants. In India numerous micropropagation units are producing millions of plantlets catering the needs for the increasing demand of quality planting materials. The advantages of this technique lie in the production of plantlets that are disease free and genetically identical to the elite mother plants. Application of plant tissue culture technique is the only viable means for the large scale production of banana planting materials which is not possible through conventional propagation. The article discusses the strategies of the mass production of commercially important banana in Mizoram using plant tissue culture techniques.