A B C D E F G H I J K L M N O P Q R S T U V W X Y Z All
Mandal, B. K.
- Possible Arsenic Contamination Free Groundwater Source in Bangladesh
Authors
1 School of Environmental Studies, Jadavpur University, Calcutta - 700 032, IN
2 Dhaka Community Hospital, Bara Magh Bazar, Dhaka - 1217, BD
Source
Journal of Surface Science and Technology, Vol 15, No 3-4 (1999), Pagination: 180-188Abstract
The groundwater arsenic contamination in Bangladesh is a phenomenon of surface ero- sion, transportation and deposition in the form of Delta and ∼lood Plain. While dealing with such geomorphological units like Tableland, Flood Plain, Delta and Hill Tract in Bangladesh, we have found the possibility of having huge arsenic contaminattion free groundwater reservoir in selected areas in Bangladesh. The results presented are the outcome of our last 5 years, field survey analysing for arsenic of water of twentyfive thousand eight hundred ninetyseven hand tubewells in sixtyfour districts of Bangladesh comprising four existing geomorphological regions (a) Deltaic region (including coastal region), (b) Flood Plain, (c) Tableland and (d) Hill Tract. In this report, we will highlight (1) the area in Bangladesh where groundwater is not arsenic contaminated and the' possibility to use shallow hand tubewells as potential groundwater resource for drinking purpose and (2) arsenic contaminations scenario of deep tubewells (above 100 meters) all over Bangladesh and suitable depth in arsenic contaminated area to get safe water.- A Brief Overview on the Chronological Development on Superconductivity
Authors
1 Department of Physics, Chandernagore Govt. College, Chandernagore, West Bengal, IN
Source
Indian Science Cruiser, Vol 26, No 2 (2012), Pagination: 32-47Abstract
Superconductors have zero resistance in electrical conductivity below their transition temperatures. Due to this property, these devices are used frequently in different fields. For producing superconductors of low transition temperatures, costly coolants are required. So researchers are involved to produce superconductors of high transition temperatures, hi the first part of this paper, an overview of superconductivity and its basic properties are described. This part also contains the chronological development and evolution of superconducting phenomena in both conventional and high temperature superconductors. Properties and crystal structure of High Temperature Superconductors (HTSC) are also discussed. In the second part of the paper, report on the research work done by the author is briefly stated. It is established that A C conduction of charge carriers in HTSC samples occurs through both tunneling and hopping. The AC Universality of the HTSC samples is shown and it confirms the basic transport process in the normal state like other polycrystalline materials.