NOPR Collection:

Biodegradation of Catechol by Fluorescent Pseudomonas for Sustainable Environment

Tue, 01 Jan 2002 00:00:00 GMT

Title: Biodegradation of Catechol by Fluorescent Pseudomonas for Sustainable Environment Authors: Tewari, Lakshmi; Malviya, Piyush Abstract: A bioremedial study was undertaken to elucidate the role of a soil bacterial isolate fluorescent Pseudomonas sp. in biodegradation and removal of organic pollutant, catechol, from the environment, Free and immobilized cells of flu orescent Pseudomonas, a plant growth promoting rhizobacteria, isolated from wheat rhizosphere and entrapped in calcium alginate beads were screened for their in vitro catechol (1,2 dihydroxy benzene) degrading efficiency . The bacterium degraded catechol, under all the tour physiological states tested. Agitation enhanced its rapid degradation. Shake cultures of both immobilized and free cells degraded 83.2 per cent and 82.2 per cent catechol, respectively in 72 h indicating high efficiency of immobilized cells for bioremedial purposes. Thus versatility of fluorescent Pseudomonas to degrade phenolic pollutants as well as to enhance plant growth can be exploited for biotechnological applications. Page(s): 70-74

Effect of Exposure to Acid Vapours on the Dielectric Behaviour of Hot Pressed Aluminium Nitride Ceramic With and Without Oxide Additives

Tue, 01 Jan 2002 00:00:00 GMT

Title: Effect of Exposure to Acid Vapours on the Dielectric Behaviour of Hot Pressed Aluminium Nitride Ceramic With and Without Oxide Additives Authors: Khanna, Arti; Kumar, A; Srivastava, K K Abstract: Dielectric behaviour of hot pressed aluminium nitride (AIN) ceramic with and without additives is studied before and after exposing the samples to some inorganic and organic acid vapours. It is observed that the dielectric dispersion increases after exposing the samples to acid vapours over and above the atmospheric humidity. In all the cases the presence of oxide additives (BeO, MgO, and Y₂O₃ is found to increase the exposure effects. Page(s): 67-69

Studies on Zirconium(IV) Selenomolybdate Gel Based Mg(II) Ion Selective Heterogeneous Membrane Sensor — Determination of Water Hardness

Tue, 01 Jan 2002 00:00:00 GMT

Title: Studies on Zirconium(IV) Selenomolybdate Gel Based Mg(II) Ion Selective Heterogeneous Membrane Sensor — Determination of Water Hardness Authors: Gupta, A P; Ikram, Saiqa; Agarwal, Himanshu Abstract: A Mg(II) ion sensor selective araldite zirconium(IV) selenomolybdate membrane sensor is prepared. It exhibits slope 23 mV/decade, which is a sub-Nernstain slope. The sensor shows working concentration range as 1.0 × 10^-5 M to 1.0 × 10^-1 M and working pH range as 2.5 to 6.0. The selectivity coefficients for 17 metal ions are studied. It can be used in the presence of some solvents up to 10 per cent v/v concentration as well as in the presence of 10^-4 to 10^-6 M Na-lauryl sulphate surfactant. The membrane electrode is put in the determination of Mg(II) ion content in synthetic samples as well as in hard water samples. The error is found to be within 2 to 6 per cent. Page(s): 61-66

Chemical Industry Wastewater Treatment Using Adsorption

Tue, 01 Jan 2002 00:00:00 GMT

Title: Chemical Industry Wastewater Treatment Using Adsorption Authors: Rathi, A K A; Puranik, S A Abstract: In a typical wastewater treatment flow sheet used by several industrial units in India, various stages of treatment include primary treatment, followed by secondary treatment, and tertiary treatment. The concentration of total dissolved solids increases during neutralization of the wastewater with acid/ alkali during primary treatment, which adversely affects the activity of microorganisms during biological treatment. The present study aims at demonstrating that adsorption as the first stage of treatment shall increase efficiency of the subsequent biological treatment. Experiments were carried out on different wastewater samples from chemical plants on adsorbents viz. activated carbon, bentonite, and lignite. The effectiveness of adsorbents in the removal of refractory organics by way of reducing chemical oxygen demand and colour is evaluated. The results of COD reduction are fitted into different models available in literature including the new model Rathi Puranik equation, which requires least experimentation for predicting COD values. Page(s): 53-60