PERFORMANCE OF SOLAR PHOTOVOLTAIC MODULE THROUGH COMBINED AIR AND WATER COOLING IN WARM AND HUMID CLIMATIC CONDITION OF INDIA

A study was conducted to evaluate the performance of solar photovoltaic module through combined air and water cooling arrangements in warm and humid climatic condition i.e. in Odisha in India during winter and summer months. Solar photovoltaic system requires neither fuel nor produces any pollutant resulting into its increased importance in today’s energy sector. The electrical output from a solar panel is a function of its efficiency and some other controlling parameters which affects the same. One of the major parameters controlling the efficiency of the panel is the temperature as it goes on increasing while using the panel in the sun. About 31 % of the incident solar radiation on the panel is converted into the useful energy and the rest part is stored in its back side causing the rise of temperature and adversely affecting its output. The stored thermal energy is of no use and decreases the durability of the in-built components of the panel due to the impact of severe thermal stresses on them resulting into reduction in its life span and conversion capability. The simplest way to enhance the efficiency of the panel is to incorporate the various cooling arrangements such as air cooling, water cooling and combined air and water cooling and assessing their effectiveness without any cooling arrangement. From the studies, it was observed that the efficiencies of solar panel were enhanced in the range of 8-11 %, 12-15% and 16-20% in air, water and combined air and water cooling respectively compared to without cooling in a clear day

Pulmonary function and fuel use: A population survey

BACKGROUND: In the backdrop of conflicting reports (some studies reported adverse outcomes of biomass fuel use whereas few studies reported absence of any association between adverse health effect and fuel use, may be due to presence of large number of confounding variables) on the respiratory health effects of biomass fuel use, this cross sectional survey was undertaken to understand the role of fuel use on pulmonary function. METHOD: This study was conducted in a village of western India involving 369 randomly selected adult subjects (165 male and 204 female). All the subjects were interviewed and were subjected to pulmonary function test. Analysis of covariance was performed to compare the levels of different pulmonary function test parameters in relation to different fuel use taking care of the role of possible confounding factors. RESULTS: This study showed that biomass fuel use (especially wood) is an important factor for deterioration of pulmonary function (particularly in female). FEV(1 )(p < .05), FEV(1 )% (p < .01), PEFR (p < .05) and FEF(25–75 )(p < .01) values were significantly lower in biomass fuel using females than nonusers. Comparison of only biomass fuel use vs. only LPG (Liquefied Petroleum Gas) use and only wood vs. only LPG use has showed that LPG is a safer fuel so far as deterioration of pulmonary function is concerned. This study observes some deterioration of pulmonary function in the male subjects also, who came from biomass fuel using families. CONCLUSION: This study concluded that traditional biomass fuels like wood have adverse effects on pulmonary function

New AGNs discovered by H.E.S.S

During the last year, six new Active Galactic Nuclei (AGN) have been discovered and studied by H.E.S.S. at Very High Energies (VHE). Some of these recent discoveries have been made thanks to new enhanced analysis methods and are presented at this conference for the first time. The three blazars 1ES 0414+009, SHBL J001355.9-185406 and 1RXS J101015.9-311909 have been targeted for observation due to their high levels of radio and X-ray fluxes, while the Fermi/LAT catalogue of bright sources triggered the observation of PKS 0447-439 and AP Librae. Additionally, the BL Lac 1ES 1312-423 was discovered in the field-of-view (FoV) of Centaurus A thanks to the large exposure dedicated by H.E.S.S. to this particularly interesting source. The newly-discovered sources are presented here and in three companion presentations at this conference.Comment: 8 pages, 3 figures, proceeding from the 25th Texas Symposium on Relativistic Astrophysics (Heidelberg, Germany, 2010

In vitro mass multiplication of Jatropha (Jatropha curcas L.) through axillary bud culture

The present investigation was conducted for mass multiplication of Jatropha curcas L. through axillary bud culture. For this nodal segment from 3-5 months old nursery grown plants were used as explants for axillary bud culture. The sterilization treatment involving dipping explants in 0.1 per cent HgCl2 solution for 5 minutes resulted in minimum contamination and maximum establishment of nodal explants. The treatment MS medium supplemented with 1.0 mg/L BAP and 1.0 mg/L IAA was the best for culture establishment, shoot proliferation and multiplication of the axillary buds which exhibited highest value in each parameter like establishment (76.1%), number of days taken for shoot initiation (3.1 days), length of longest shoot (6.8 cm), number of leaves on main shoot (7.1) and number of shoots per explant (6.3). Among different treatments for root initiation, half MS media fortified with 1 mg/L IBA, 3 mg/ L NAA and 0.25 g AC gave best result in maximum number of rooting percentage (60) with minimum time taken for root initiation (13.3 days), produced maximum number of roots per shoots (5.1) and length of longest root (4.9 cm) when established shoots were treated with it. Such produced plantlets showed nearly cent per cent survival after hardening and acclimatization. It showed that explants surface sterilized with 0.1 per cent HgCl2 solution for 5 minutes inoculated in MS medium supplemented with 1.0 mg/L BAP and 1.0 mg/L IAA and half MS media fortified with 1 mg/L IBA, 3 mg/L NAA and 0.25 g AC were best in shoot establishment and root development respectively for mass multiplication of J. curcas L. through axillary bud culture

VHE Gamma-ray Afterglow Emission from Nearby GRBs

Gamma-ray Bursts (GRBs) are among the potential extragalactic sources of very-high-energy (VHE) gamma-rays. We discuss the prospects of detecting VHE gamma-rays with current ground-based Cherenkov instruments during the afterglow phase. Using the fireball model, we calculate the synchrotron self-Compton (SSC) emission from forward-shock electrons. The modeled results are compared with the observational afterglow data taken with and/or the sensitivity level of ground-based VHE instruments (e.g. STACEE, H.E.S.S., MAGIC, VERITAS, and Whipple). We find that modeled SSC emission from bright and nearby bursts such as GRB 030329 are detectable by these instruments even with a delayed observation time of ~10 hours.Comment: Proceeding of "Heidelberg International Symposium on High Energy Gamma-Ray Astronomy", held in Heidelberg, 7-11 July 2008, submitted to AIP Conference Proceedings. 4 pages, 3 figures, 1 tabl

Coexistence of Band Jahn Teller Distortion and superconductivity in correlated systems

The co-existence of band Jahn-Teller (BJT) effect with superconductivity (SC) is studied for correlated systems, with orbitally degenerate bands using a simple model. The Hubbard model for a doubly degenerate orbital with the on-site intraorbital Coulomb repulsion treated in the slave boson formalism and the interorbital Coulomb repulsion treated in the Hartree-Fock mean field approximation, describes the correlated system. The model further incorporates the BJT interaction and a pairing term to account for the lattice distortion and superconductivity respectively. It is found that structural distortion tends to suppress superconductivity and when SC sets in at low temperatures, the growth of the lattice distortion is arrested. The phase diagram comprising of the SC and structural transition temperatures $T_c$ and $T_s$ versus the dopant concentration $\delta$ reveals that the highest obtainable $T_c$ for an optimum doping is limited by structural transition. The dependence of the occupation probabilities of the different bands as well as the density of states (DOS) in the distorted-superconducting phase, on electron correlation has been discussed.Comment: RevTex, 4 pages, 4 figuers (postscript files attached) Journal Reference : Phys. Rev. B (accepted for publication

Developing procedures for assessment of ecological status of Indian River basins in the context of environmental water requirements

River basins / Ecology / Indicators / Environmental flows / Environmental management / Habitats / Biota / Fish / Ecosystems / India / Krishna River Basin / Chauvery River Basin / Narmada River Basin / Periyar River Basin / Ganga River Basin