Bapatla Engineering College

About: Bapatla Engineering College is a based out in . It is known for research contribution in the topics: Fault (power engineering) & Surface roughness. The organization has 285 authors who have published 355 publications receiving 1918 citations.

A Study on Biochemical Changes in the Fresh Water Fish, Catla catla (Hamilton) Exposed to the Heavy Metal Toxicant Cadmium Chloride

Abstract: Cadmium (Cd), one of the twenty three heavy metal toxicants, is widely used in Ni-Cd batteries manufacture, metal and mining industry, dentistry etc. because of its non-corrosive nature. Cd is released in considerable amounts through industrial effluents into soil, surface and ground water systems. These excess amounts in addition to naturally occurring levels gradually build up to toxic levels causing damage to the biota of the aquatic ecosystem. It shows biomagnification and has greater half-life periods. Cd was found to interfere with many protein and carbohydrate metabolisms by inhibiting the enzymes involved in the processes. The present study evaluates toxicity of Cd and its impact on biochemical constituents like glucose, glycogen, total proteins, lipid and free aminoacids in the fresh water edible carp Catla catla as Cd bioaccumulation can affect humans through biomagnification. Short term tests of acute toxicity were performed over a period of 96 hours using cadmium chloride. The renewal technique was followed by exposing the fish to test solutions of different concentrations in the range of 1 mg/L to 8 mg/L. Preliminary experiments were conducted to choose concentrations that resulted in the mortality of the fish in the range of 10-90%. The toxicity experiments were then conducted using the chosen concentrations of CdCl2 on the fingerlings ( Wt. 6±1 grams ) in triplicate and the LC 50 was determined using simple graphic ( % Mortality Vs. Log Concentration), probit graphic ( Probit value Vs. Log concentration) and unweighted regression analysis methods. The calculated average 96-hr LC50 is 4.533 mg/L and the equation for the dose-mortality regression line was found to be Y = 2.65X + 3.368. Levels of the five biochemical constituents viz., Glucose, Glycogen, Total proteins, Lipids and Free aminoacids were determined by standard biochemical procedures in the five tissues i.e., muscle, gill, liver, heart and kidney of unexposed (Control) healthy fish and the fish exposed to 96-hr LC50 (Lethal) and sub-lethal concentrations (1/10th of the lethal dose for 7 days of exposure) of cadmium chloride. Results showed significant fall in all the biochemical constituents in all the tissues except glucose prompting to suggest that the fish cultured in the aquatic systems closer to the industrial locations would not have the expected nutritive value. The elevated levels of glucose are apparently indicative of the organism's response to the toxicant stress. Also, such fish when consumed as food lead to the deposition of the heavy metal in the soft tissues of the human body leading to exposure health effects. Key words: Toxicity; Heavy metal; Cadmium chloride; Biomagnification; Catla catla DOI: 10.3126/kuset.v3i2.2890 Kathmandu University Journal of Science, Engineering and Technology Vol.3, No.2, August 2007, pp 1-11

Experimental studies in Ultrasonic Pulse Velocity of roller compacted concrete pavement containing fly ash and M-sand

Abstract: This paper presents the experimental investigation results of Ultrasonic Pulse Velocity (UPV) tests conducted on roller compacted concrete pavement (RCCP) material containing Class F fly ash of as mineral admixture. River sand, M-sand and combination of M-sand and River sand are used as fine aggregate in this experimental work. Three types of fly ash roller compacted concrete mixes are prepared using above three types of fine aggregates and they are designated as Series A (River sand), Series B (manufactured sand) and Series C (combination of River sand and M-sand). In each series the fly ash content in place of cement is varied from 0% to 60%. In each series and for different ages of curing (i.e 3, 7, 28 and 90 days) forty two cube specimens are cast and tested for compressive strength and UPV. The UPV results of fly ash containing roller compacted concrete pavement (FRCCP) show lower values at all ages from 3 days to 90 days in comparison with control mix concrete (0% fly ash) in all mixes. However, it is also observed that Series B and C mixes containing fly ash show better results in UPV values, compressive strength and Dynamic Elastic Modulus in comparison to Series A mixes with fly ash. Relationships between compressive strength of FRCCP and UPV and Dynamic Elastic Modulus are proposed for all series mixes. A new empirical equation is proposed to determine the Dynamic Elastic Modulus of FRCCP.