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Diversity of birds at Panipat refinery, Haryana (India)
No full textAvifaunal study was carried out in Panipat refinery area before and after commissioning. A total of 63 birds were observed during the study, of which 39 and 49 birds were present during 1992 and 2001 respectively. Of these, 25
birds were common during both the study period. Blue rock pigeon was most dominant during 1992 whereas house sparrow was dominant during 2001. Species diversity index was found
to be 5.26 and 6.64 in respective years. Jaccard’s and Sorenson similarity indices were 0.40 and 0.57 respectively. Majority of birds were insectivorous in habits followed by granivorous birds in 1992 and piscivorous birds in 2001. The study reveals that less diversity was observed in 1992 when Panipat refinery was commissioned, but more birds especially aquatic ones were observed after the commissioning of the refinery. This has been attributed to increase in birds habitats due to developments of wetlands in and outside refinery, development of green belt around refinery and increase in green cover of area due to boosting of agroforestry and social forestry
Study of variations of water quality of Mumbai coast through multivariate analytical techniques
No full textAlumina Supported Co–K–Mo Based Catalytic Material for Diesel Soot Oxidation
No full textAlumina supported Co–K–Mo based mixed
metal oxide type catalytic materials have been prepared by
co-impregnation. These catalysts show excellent activity
for carbon as well as diesel soot oxidation, which could be
due to the redox properties of Mo and Co as well as to a
synergistic effect of molybdenum, cobalt, and K contents.
The catalyst containing 5 wt% molybdenum shows a
lowering of carbon oxidation by about 190 �C under loose
contact conditions as compared to the non-catalyzed
reaction, as well as to bare alumina. Characterization
studies suggest a composite nature of these materials, while
thermal stability investigations confirm the stable nature.
The selected catalyst has been studied by XPS, however, it
is difficult to conclude which are the important factors
contributing to the catalytic activity. It appears to be a
synergistic effect of Co, K, and Mo components as these
catalysts show much improved activity as compared to the
individual components in supported and unsupported
forms
Defluoridation of drinking water using chemically modified bentonite clay
No full textAdsorption potential of metal oxide (lanthanum, magnesium and manganese) incorporated bentonite clay
was investigated for defluoridation of drinking water using batch equilibrium experiments to gain insight of
adsorption behavior, kinetics and mechanisms of adsorption of fluoride ion. The effect of various physicochemical
parameters such as pH, adsorbent dose, initial fluoride concentration and the presence of
interfering co-ions on adsorption of fluoride has been investigated. The 10%La-bentonite shows higher
fluoride uptake capacity for defluoridation of drinking water as compared to Mg-bentonite, Mn-bentonite
and bare bentonite clay. The uptake of fluoride in acidic pH was higher as compared to alkaline pH. The
equilibrium adsorption data fitted reasonably well in both Langmuir and Freundlich isotherm models. It was
also observed that in the presence of certain co-existing ions can have positive effect on removal of fluoride,
while carbonate and bicarbonate anions show deleterious effect. The rate of adsorption was reasonably rapid
and maximum fluoride uptake was attained within 30 min. The modified adsorbent material shows better
fluoride removal properties for actual field water, which could be due to the positive effect of other co-ions
present in the field water
Sea water intrusion studies near Kovaya limestone mine, Saurashtra coast, India
No full textThe Kovaya Limestone Mine is situated on the Saurashtra coast of India. Though the mine is dependent on the desalination plant installed in the plant for its domestic and industrial water requirements, there is significant withdrawal of groundwater by the large number of bore wells
and open wells, which are present in the agricultural
fields lying in and around the leased area of the mine. The heavy withdrawal of groundwater has led to intrusion of seawater. The present work entails study of possible seawater intrusion by chemical analysis of major cations and anions in selected groundwater samples. Very high total
dissolved solids in the range of >1,000 mg/l and high chloride in the range of 103 mg/l to 3,899 mg/l have been measured in the groundwater samples. ‘Resistivity Imaging Survey’ has also been carried out on selected profiles in the study area. The Electrical Resistivity Tomography images indicate very low resistivity zones (∼0–3 � m) in the
bottom portion of the resistivity depth sectio
Fate and Degradation of POP-Hexachlorocyclohexane
No full textHexachlorocyclohexane (HCH) and its isomers are one of the most frequently detected chlorinated contaminants in the environment. In spite of the ban on technical grade HCH and restricted use of γ -HCH (lindane), its residues have not stopped from entering the environment. Its extensive use in the past, present use of lindane in several countries, unused stockpiles of date-expired HCH from earlier manufacturing, as well as leachates from earlier disposal
at dump sites continue to pollute the biosphere. Because HCH is a persistent organic pollution (POP) known to have several toxic and deleterious effects on human health and wildlife, it becomes imperative to remove this substance of serious concern to the global community. A better understanding on the fate and degradation of this POP in the environment will facilitate in drawing measures to
mitigate this chemical and bring about bioremediation of already contaminated sites. This review focuses on the fate, contamination levels, abiotic and biotic degradation of HCH isomers, genes and enzymes involved in microbial degradation, and future research needs in this area
Treatment of waste gas containing diethyldisulphide (DEDS) in a bench scale biofilter
No full textWaste gas containing diethyldisulphide (DEDS) is generated from various industries including pulp and paper, refinery, rayon and molasses based distilleries, etc. DEDS has odour threshold detection with an average concentration of 10�9 mg/m3 at 25 �C. DEDS is toxic to bacteria, fungus and also to mammals when exposed for a long period. Waste gas containing DEDS require proper treatment prior to discharge
into the environment. DEDS containing waste gas was treated in a biofilter, packed with compost along with wooden chips and enriched with DEDS degrading microorganisms. The biofilter could remove DEDS to the extent of 94 ± 5% at a loading of 1.60 g/m3/h with an empty bed retention time of 150 s. At optimal operating conditions, the average moisture content required by the biofilter was in the range of 60–65%. The biodegradative products of DEDS were thiosulphate and sulphate
Purification and Characterization of a Novel Plant-type Carbonic Anhydrase from Bacillus subtilis
No full textCarbonic anhydrase enzyme, one of the fastest known enzymes, remains largely unexplored in prokaryotes when compared to its mammalian counterparts despite its ubiquity. In this study, the enzyme has been purified from Bacillus subtilis SA3 using sequential Sephadex G-75 chromatography, DEAE cellulose chromatography, and sepharose-4B-L-tyrosinesulphanilamide affinity chromatography and characterized to provide additional insights into its properties. The apparent molecular mass of carbonic anhydrase obtained by SDS-PAGE was found to be approximately 37 kDa. Isoelectric focusing of the purified enzyme revealed an isoelectric point (pI) of around 6.1 when compared with marker. The presence of metal ions such as Zn2+, Co2+, Cu2+, Fe3+, Mg2+, and anion SO4 − increased enzyme activity while strong inhibition was observed in the
presence of Hg2+, Cl−, HCO3 −, and metal chelator EDTA. The optimum pH and temperature for the enzyme were found to
be 8.3 and 37°C, respectively. Enzyme kinetics with p-nitrophenyl acetate as substrate at pH 8.3 and 37°C determined the Vmax and Km values of the enzyme to be 714.28 μmol/mg protein/min and 9.09 mM, respectively. The Ki value for acetazolamide was 0.22 mM, compared to 0.099 mM for sulphanilamide. The results from N-terminal amino acid sequencing imply the purified protein is a putative beta-carbonic anhydrase with close similarities to CAs from plants, microorganisms
Herbal pharmaceutical wastewater treatment by a pilot scale upflow anaerobic sludge blanket (UASB) reactor
No full textHerbal pharmaceutical industry has grown tremendously in the last few decades. As such, literature on the treatment of this wastewater is scarce. Water pollution control problems in the developing countries need to be solved through application of cost effective aerobic/anaerobic
biological systems. One such system-the upflow anaerobic sludge blanket (UASB) process which is known to be cost effective and where by-product recovery was also feasible was applied for treatment of a high strength wastewater for a period of six months in a pilot scale upflow anaerobic sludge blanket (UASB) reactor with a capacity of 27.44 m3 Studies were carried out at various organic loading rates varying between 6.26 and 10.33 kgCOo/m3/day and hydraulic
retention time (HRT) fluctuating between 33 and 43 hours. This resulted in chemical oxygen demand (COO). biochemical oxygen demand (BOD) and suspended solids (SS) removal in the
range of 86.2%-91.6%, 90.0%-95.2% and 62.6%-68.0% respectively. The biogas production varied between 0.32-0.47 m3/kgcoo added. Sludge from different heights of UASB reactor was collected and subjected to scanning electron microscopy (SEM). The results indicated good granulation with efficient UASB reactor performance
