Time filter

Source Type

Markandey D.,Central Pollution Control Board | Salar R.K.,Choudhary Devi Lal University | Markandey N.,University of Delhi | Trivedi R.C.,Central Pollution Control Board
Indian Journal of Environmental Protection | Year: 2011

Contamination of aquatic resources by a variety of heavy metals is of growing concern because of health risk posed by the exposure to flora and fauna as well as human being. The vast majority of toxic metals are the waste products/byproducts of industrial and metallurgical processes. Other possible sources include the effluent from electroplating, storage battery manufacturing industries, tanneries, municipal sludges, extractive metallurgy processes, and metal finishing operations contains high amount of dissolved metals and the concentration reaches to a significant range. The value is very high in relation to water quality standards, as prescribed by the various regulatory authorities at national and international levels. The conventional decontamination methods are chemical precipitation, solvent extraction, electrodialysis, electrolytic extraction, application of ion exchange resins, activated charcoal adsorption, etc., which involves high operation and maintenance costs, which has stimulated a search of new decontamination technologies for effectiveand economic removal of such priority pollutants. Microorganisms, like bacteria, yeast and fungi, as well as algae can accumulate large amounts of heavy metal ions. Biosorption is considered to be a fast physical or chemical process. The biosorption rate depends on the type of the process. Microbial removal of heavy metals offers the advantages of low operating cost, minimizing secondary problems with metal-bearing sludge and high efficiency in detoxifying very dilute effluents. To assess the said qualities, the composite sample was collected from a tannery to study the metal removal efficiency of the promising isolate Rhizopus stolonifer in the laboratory. The chemical analyses of the effluent have shown the significantly high Cr (T) concentration ((705 mg/L). Various batch experiments were performed with dilute effluent. The mycelial mass of the isolate was tested under various physical treatment conditions, like formalin treated, alkali treated and untreated mycelia. The results of formalin treated biomass have shown improvement in the sorption efficiency of the isolate (98%) than the native culture (87%). However, the alkali treatments of the biomass have substantially reduced the efficiency (57%). Further optimizations in the experimental variables have shown improvement of removal of target metal. The performances of EDTA and NTA were found satisfactory upto 4th cycle of sorption/desorption. This paper describes the findings in detail. © 2011 - Kalpana Corporation.

Gupta M.,National Institute of Technology Kurukshetra | Chauhan R.P.,National Institute of Technology Kurukshetra | Garg A.,Arya PG College | Kumar S.,Choudhary Devi Lal University | Sonkawade R.G.,Inter University Accelerator Center
Indian Journal of Pure and Applied Physics | Year: 2010

Natural radioactivity is composed of the cosmogenic and primordial radionuclides. It is common in the rocks and soil that make up our planet, in water and oceans, and in our building materials and homes. Natural radioactivity in sand and soils comes from 238U and 232Th series and natural 40K. Radon is formed from the decay of radium which in turn is formed from uranium. The gaseous radioactive isotope of radon from natural sources has a significant share in the total quantum of natural sources exposure to human beings. Gamma radiation from 238U, 232Th and 40K represents the main external source of irradiation of the human body. In the present study, the activity for 238U, 232Th and 40K is found to vary from 45±1.2 to 97± 4.9 Bq/kg, 63 ± 2.0 to 132 ± 3.2 Bq/kg and 492 ± 5.9 to 1110 ± 10.5 Bq/kg, respectively in the soil samples while the variations have been observed from 63 ± 3.8 to 65 ± 3.7 Bq/kg, 86 ± 2.5 to 96 ± 2.6 Bq/kg and 751± 7.7 to 824 ± 8.2 Bq/kg, respectively in the sand samples.

Dahiya T.,CCS Haryana Agricultural University | Sihag R.C.,CCS Haryana Agricultural University | Gahlawat S.K.,Choudhary Devi Lal University
Journal of Fisheries and Aquatic Science | Year: 2012

Haematological profile of an animal is the reflection of its immunological status. Fishes are prone to infections by several pathogens which influence the immunity of the affected individuals. The effect of three probiotics on four haematological parameters viz., level of haemoglobin, total erythrocyte count, total leucocytes count hematocrit/packed cell volume of Indian magur (Clarius batrachus L.) was studied over a period of eight weeks. The level counts of all these four parameters decreased significantly in the blood of fish administered with pathogenic organisms as compared to the control; the fish administered with pathogenic organisms died after three weeks. The level counts of hematological parameters showed significant increase in the blood of fish treated with probiotics alone versus control and also in fish administered with pathogenic organisms versus probiotics. A comparison among the three probiotics revealed that, probiotic 1 was more effective than probiotic 3 and probiotic 2; the effect of latter stood at the lowest level. © 2012 Academic Journals Inc.

Sindhu M.,Guru Jambheshwar University of Science and Technology | Ahlawat N.,Guru Jambheshwar University of Science and Technology | Sanghi S.,Guru Jambheshwar University of Science and Technology | Agarwal A.,Guru Jambheshwar University of Science and Technology | And 2 more authors.
Current Applied Physics | Year: 2012

Single phase perovskite CaTiO 3 has been synthesized by conventional solid state reaction technique. The ceramic was characterized by XRD at room temperature and its Rietveld refinement inferred orthorhombic crystal structure with the space group Pbnm. The field dependence of dielectric relaxation and conductivity was measured over a wide frequency range from room temperature to 673 K. Analysis of Nyquist plots of CaTiO 3 revealed the contribution of many electrically active regions corresponding to bulk mechanism, distribution of grain boundaries and electrode processes. The dc conductivity depicted a semiconductor to metal type transition. Frequency dependence of dielectric constant (ε′) and tangent loss (tan δ) show a dispersive behavior at low frequencies and is explained on basis of Maxwell-Wagner model and Koop's theory. Both conductivity and electric modulus formalisms have been employed to study the relaxation dynamics of charge carriers. The variation of ac conductivity with frequency at different temperatures obeys the universal Jonscher's power law (σ ac α ω s). The values of exponent 's' lie in the range 0.13 ≤ s ≤ 0.33, which in light of CBH model suggest a large polaron hopping type of conduction mechanism. © 2012 Elsevier B.V. All rights reserved.

Ahlawat N.,Guru Jambheshwar University of Science and Technology | Sanghi S.,Guru Jambheshwar University of Science and Technology | Agarwal A.,Guru Jambheshwar University of Science and Technology | Ahlawat N.,Choudhary Devi Lal University | And 2 more authors.
AIP Conference Proceedings | Year: 2011

Barium bismuth silicate glasses (BBS glasses) with composition were prepared by normal melt quench technique. The dispersive conductivity and dielectric losses in these glasses were investigated by impedance spectroscopy. The analyses of ac conductivity spectra show a crossover from ion hopping conductivity to nearly constant loss (NCL) contribution in all the glasses. The variations in dielectric constant ε*(ω)=ε′(ω)- íε″(ω) with frequency and temperature indicate an increase in electrode polarization, which reduces the dipolar relaxation effects in these glasses. The increased concentration of BaO in the glass composition reduces the dielectric losses in the present glasses. © 2011 American Institute of Physics.

Godara A.S.,Choudhary Devi Lal University | Poonia U.,Choudhary Devi Lal University | Bishnoi D.K.,Choudhary Devi Lal University | Prakash S.,Choudhary Devi Lal University
Indian Journal of Agricultural Research | Year: 2015

The paper seeks to examine the growth behaviour of area, yield and production of American cotton and their association with its most influential factor price. The correlation of area, yield and production with price has been examined in this paper as well as impact of lagged year's price has also been observed. The contribution of area, yield, price and their interaction has also been discussed. The results indicated that during first and second period, the American cotton production has risen due to its area increment. The role of the yield has not found as major as expected. However, there has been drastic change in the situation regarding yield during this period. The new technology especially high-yielding varieties of seeds provided to farmers remained enough to motivate farmers of Haryana to replace the Desi cotton with American cotton but at the same time the correlation between price and other variables has not found very high during third period whether it has observed negative during all sub-study period regarding to yield. However, the lagged price of American cotton has succeeded to influence the current year's area, yield and production. As far as contribution of price to the incremental output in value term is related, price has remained the major factor during all the periods except for the third period during which its position has been overtaken by the American cotton.

Loading Choudhary Devi Lal University collaborators
Loading Choudhary Devi Lal University collaborators