Asian Transactions on Science & Technology

Volume: 02, Issue: 03, July 2012
ISSN 2221-4283


Title: Solar pond and its application to desalination
Author(s): A.Z.A. Saifullah, A.M. Shahed Iqubal and Anirban Saha
Paper ID: ATST-50201035
Pages: 1 - 25
Abstract: This paper discusses the solar pond technology and how it is applied to desalination. A solar pond is a shallow body of water which acts as a solar collector with integral heat storage for supplying thermal energy. Solar ponds are mainly two types: convective solar ponds and non-convective solar ponds. The shallow solar pond and the deep saltless pond are the examples of convective type. There are three types of non-convective solar ponds: salinity gradient solar pond (SGSP), membrane solar pond and polymer gel layers solar pond. A SGSP is a pool of water about 1-5 m deep, which contains dissolved salts to establish a stable density gradient. There are three layers in a SGSP: upper convective zone (UCZ), lower convective zone (LCZ) and salinity gradient non-convective zone (NCZ) in the middle. Incident solar energy is collected and stored which may be delivered at temperature near 100C. The SGSP is the most eco-friendly and environment-friendly among all the solar energy systems for electricity generation, desalination, hot water applications in agriculture, green house heating, domestic hot water production and space heating and cooling of buildings. Nevertheless, a SGSP is more cost-effective since its collection cost per square meter is only one-fifth of that of a liquid flat plate collector, and cost of 1KWh of electricity production by a SGSP is only one-fifth of that produced by photovoltaic cells. A solar pond multi-stage flash distillation system (SPMSF) is very promising for Bangladesh. MSF plants can produce 6-60 L/m2/day, whereas for typical solar stills it is 3-4 L/m2/day.

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Title: Thermal Analysis of the Mix Prefab&Earthen Building in Dilekkaya, North Cyprus (June 2012)
Author(s): Yasemin Mesda, and Dr. Bilge Isik
Paper ID: ATST-50219035
Pages: 26 - 34
Abstract: The aim of this study is to contribute to the sustainability of healthy living in Cyprus. Earthen architecture is known with thermal comfort. A new earthen construction technology has been applied using prefabricated wall in the indoors and earthen material for external walls. The heat transfer coefficient and total heat loss of the prefab&earthen building has been analyzed and calculated on ceiling, external walls, roof and windows according to the influence of the bio-climatic comfort conditions of Cyprus. This new mix prefab&earthen house building was constructed in the Dilekkaya village in North Cyprus. The aim of the construction of the new mix earthen house is to explain the technology and sustainability of the earth material at today. Earth is the main material of the exterior walls in which shotcrete machine is used to apply the earth. Light steel material is used in the construction of the interior walls which is suitable for the prefabricated technique. The contemporary construction technology was used during the construction of this building. Exterior walls were finished in 3 days of this 6mx6m house. Interior walls were prepared in the workshop during the exterior walls' construction. General information about the Dilekkaya village, its location and history of the mix earthen buildings are mentioned in the scope of this study. Moreover, the architectural characteristics of this new house are analyzed according to the heat transfer coefficients and heat loss calculation. The importance, advantages, energy-saving opportunities and natural climate conditions of the earth material can be seen after these calculations. Furthermore, this study aims to show how country's total energy consumption will be reduced by using the earthen material.

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Title: Palynological Analysis of Late Cretaceous Sediments of the Nkporo Formation in the Afikpo Sub-Basin, Southeastern Nigeria
Author(s): A. U. Okoro, C. N. Nwojiji, F.N.Osegbo, V.O. Ndubueze
Paper ID: ATST-50228034
Pages: 35 - 46
Abstract: The Late Cretaceous Afikpo Sub-basin was installed following the Santonian "squeeze". The Nkporo Formation which comprises of interbedded sandstones, dark grey shales, siltstones and limestone lenses is the basal unit of this Sub-basin. Palynological analysis of shale samples from surface outcrops of the Formation yielded sixty-seven (67) palynomorphs species, made up of thirty-eight (38) pollen species, sixteen (16) spores species, thirteen (13) dinoflagellate cyst species and microforaminiferal wall-linings. The palynological assemblage consists of abundant Monocolpates, Tricolporates, Laevigates, triletes, Monolete spores and Dynocyst species. The presence of Dynocyst species of Andallussiella polymorpha, Coronifera tubulosa and Senegalinium bivacatum suggest that the shales outcropping in Afikpo and Asaga Amangwu areas (lower-middle part of the Formation) were deposited during the late Campanian. The upper part of the Formation outcropping on the scarp-slope of the Enugu-Okigwe Cuesta near Amaiyi and Nguzu Edda villages were dated early - mid Maastrichtian using Palynomorph species Longapertites marginatus, Monocolpites marginatus, Proxapertites cursus, Mauritidites crassibaculatus, Constructipollinities ineffectus, Proxapertites operculatus and Syncolporites marginatus; and dinoflagellate species of Dinogymnium undulosum and D. acummunatum. The environment of deposition has been interpreted as marginal to open marine. The recovered palynoflora fall within the Proxapertites Assemblage Zone and displays characteristics of the Senonian Palmae Province of Campanian - Maastrichtian elements recorded from tropical - sub tropical regions of South America, Africa and India.

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