57 research outputs found
Assessment of sources and distribution metals in groundwater of Pondicherry region, India
The proposed study investigates the seasonal variation in the concentration and the source of the heavy metals like Mn, Cu, Pb, Zn and Fe in the groundwater samples of Pondicherry region. The study results reveal that, the heavy metal concentration is high during South West Monsoon season (SWM) compared to that of North East Monsoon season (NEM). The pH was near neutral and metal load representing most of the samples were low during NEM. Statistical analysis shows that the 63.7 % of the total variance is observed during NEM and 68.9% during SWM. Geographic information system (GIS) tool was considered for the study to understand the environmental pollution status of the groundwater systems of the study area and to identify the groundwater quality parameters. The multivariate statistical analysis explains that the source of trace metal in the groundwater is derived from natural origin except copper and lead as these contaminants were derived from anthropogenic activities. Based on the output of WATEQ4F, several species of heavy metals exist, in which the dominant species are Mn, CuCl2, PbCO3, Fe and Zn
A study on the defluoridation in water by using natural soil
Removal of excess fluoride (Fâ) from the water has been attempted by several authors by using different materials both natural and artificial. The main aim of this paper was to attempt the fluoride removal by using the locally available red soil adopting column method. The red soil was mixed in different proportion with sand in order to increase the porosity and permeability property of the medium. It was optimized for 4:1 ratio of red soil to sand and it was used for the following experiment. The experiment was conducted in 11 batches for a period of about 9,213 min. Fresh standard solution of F was used in each batch, prepared from Orion 1,000 ppm solution. The samples were collected and analyzed for pH, EC (Electrical Conductivity) and HCO3. Rate of flow of water and efficiency of adsorption were calculated and compared with the fluoride removal capacities of the medium. The medium used for the fluoride removal was subjected to FTIR analysis before and after the experiment. The variation of IR spectrum before and after treatment signifies the changes in the OH bonding between Al and Fe ions present in the soil. The variation in pH decreased during the course of defluoridation. Higher F removal was noted when flow rate was lesser. An attempt on the regeneration of the fluoride adsorbed soil was also made and found to be effective
Variable Stars in Galactic Globular Clusters
Based on a search of the literature up to May 2001, the number of known
variable stars in Galactic globular clusters is approximately 3000. Of these,
more than 2200 have known periods and the majority (approximately 1800) are of
the RR Lyrae type. In addition to the RR Lyrae population, there are
approximately 100 eclipsing binaries, 120 SX Phe variables, 60 Cepheids
(including population II Cepheids, anomalous Cepheids and RV Tauri) and 120
SR/red variables. The mean period of the fundamental mode RR Lyrae variables is
0.585, for the overtone variables it is 0.342 (0.349 for the first-overtone
pulsators and 0.296 for the second-overtone pulsators) and approximately 30%
are overtone pulsators. These numbers indicate that about 65% of RR Lyrae
variables in Galactic globular clusters belong to Oosterhoff type I systems.
The mean period of the RR Lyrae variables in the Oosterhoff type I clusters
seems to be correlated with metal abundance in the sense that the periods are
longer in the more metal poor clusters. Such a correlation does not exist for
the Oosterhoff type II clusters. Most of the Cepheids are in clusters with blue
horizontal branches.Comment: 45 pages, 10 figures, to be published in AJ November 200
Performance of Concrete Filled in Cold Form Steel Sheet with Shear Connector under Pure Bending
172-175This paper investigates Performance of concrete filled in
cold form steel sheet with shear connector under pure bending. A model is created using <span style="mso-bidi-font-weight:
bold;mso-bidi-font-style:italic">ABAQUS to predict the performance of concrete filled in
cold form steel sheet with shear connector to find moment carrying capacity
ultimate point. The concrete filled
in cold form steel sheet<span style="mso-bidi-font-weight:bold;
mso-bidi-font-style:italic"> beam investigated and compared by finite element
programme ABAQUS against
experimental and theoretical data<span style="mso-bidi-font-weight:bold;
mso-bidi-font-style:italic">.
The reinforced concrete beam shuttered
with the cold formed steel sheet
and
stud T shaped shear connectors
were welded on three sides of the beam. Bracings were provided on the top of the beam in the pure bending region.
The moment capacity depends on the parameter of q, which is ratio of force in
shear connectors and force in bottom reinforcement.
The experiment was carried out with various spacing of shear such as 75,100,125
and 150mm, we found that beams
of 75mm spacing of shear connector takes higher ultimate load. The comparison
of ultimate bending moment vs. spacing
of shear connector for the beams analyzed with experimental, theoretical and
ABAQUS value gives 75 mm spacing attain the good ultimate strength of the beam.
</span
Identification of Recharge Processes in Groundwater in Hard Rock Aquifers of Madurai District Using Stable Isotopes
Stable isotopes of H and O are the integral parts of water molecule and serve as ideal tracers to understand the recharge processes in groundwater. Hence, a study has been conducted in hard rock aquifers of Madurai District of Tamilnadu to identify the recharge processes using stable isotopes. A total of 54 groundwater samples were collected representing the entire district from various lithounits during post monsoon. Samples were analysed for pH, EC, Ca2+, Mg2+, Na+, K+, Clâ HCO3â, SO42â, PO43â, H4SiO4, Fâ, δ18O and δD. Clâ and HCO3â were the dominant ions in groundwater samples. Average values of Clâ and HCO3â ranged from 247 and 244 mg/L in fissile hornblende biotite gneiss, 262 and 268 mg/L in Charnockite, 75 and 185 mg/L in quartzite, 323 and 305 mg/L in granite, 524 and 253 mg/L in floodplain alluvium rock types. Geochemical signatures of groundwater were used to identify the chemical processes that control hydrogeochemistry. Interpretation of δ18O and δD indicates recharge from the meteoric water in charnockite, quartzite, granite and some samples of fissile hornblende biotite gneiss. It is also inferred that recharge take place from evaporated water in floodplain alluvium and fissile hornblende biotite gneiss
Drug Utilization of Antimicrobials in Pediatrics Population at a Tertiary Care Hospital in Kancheepuram District of Tamilnadu, India
ABSTRACT Drug utilization is an essential part of Pharmacoepidmology and it describes the extent nature and determinants of drug exposure. The aim of the study was to evaluate drug utilization of antimicrobials in pediatrics at SRM medical college. A prospective cross sectional study was carried out for seven months, totally 109 prescription with antibiotics was collected the most commonly prescribed drugs were third generation cephalosporin's like ceftriaxone(27.9%), cefataxim(20.1%), followed by penicillin's ampicillin(12.9%),amoxicillin(12.9%), and there combinations and the highest reported diseases in pediatrics are broncholitis(24.9%), and acute gastro enteritis(22.0%)
Application of statistical techniques to identify the hydrogeochemical processes in coastal aquifers of Pondicherry region- Tamil Nadu
Š 2014, Capital Publishing Company.Groundwater pollution can be illustrated as degrading of water quality for any usage. The Eleven hydrochemical parameters of groundwater samples from different formation were used in this study to understand groundwater chemistry in this complex multilayer aquifer system. The statistical analysis of the results shows that dominant process of weathering of feldspar, pyroxene and ion exchange. The water flows along the formation dissolving these ions along its flow path through the process of leaching of the secondary salts inherited in the formation obtained by the mixing of several geochemical processes. The anthropogenic impacts in the groundwater are noted in the younger formation than that of Cretaceous and Lower Cuddalore
A Study on the Behaviour of Total Carbon and Dissolved Organic Carbon in Groundwaters of Pondicherry Region, India
Organic carbon concentrations can vary considerably, both spatially and temporally, so a large number of analyses are frequently required to produce a representative estimate of concentrations. Natural organic carbon is mainly derived from decomposing vegetation and other organic matter in the soil zone. In this scenario, a baseline attempt was made to study the behaviour of organic carbon content in groundwater by collecting samples from the layered aquifer sequence of Pondicherry. The samples were collected from Recent Alluvium (30), Upper Cuddalore(13), Lower Cuddalore (13), Other Tertiary formation (7), Mixed aquifer (5) and Cretaceous formations (24). The analysis of these samples show that higher concentration of Dissolved Organic Carbon (DOC) was noted in the Alluvial formation and the average concentration was higher in Upper Cuddalore Formation. The samples of these formations were compared with pH, Ionic strength, and log pCO2 and bicarbonate concentration. The alluvial aquifer shows that pH governed dissolution along the coastal tracts and in Upper Cuddalore formation itâs based on interaction between aquifer matrix and groundwater
A comparative study on the arsenic levels in groundwaters of gangetic alluvium and coastal aquifers in India
Spatial and temporal variations of radon concentrations in groundwater of hard rock aquifers in Madurai district, India
Radon (222Rn) and other radionuclides in groundwater can lead to health problems if present in higher concentrations. A study was carried out in Madurai district of Tamilnadu by collecting groundwater samples for four different seasons and aims to identify the regions with higher 222Rn concentration along with their spatial and seasonal variations. 222Rn has been compared with field parameters, log pCO2, major ions and uranium to detect the factors responsible for the higher concentration in groundwater. The weathering process induces the release of higher uranium ions from the granitic terrain from the rock matrix which enhances the 222Rn levels in groundwater
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