Heavy Metal Analysis of Ponderosa Pine Tree Rings along the Upper Pecos River

Yiqiao Zou, Donald Brandvold and Zhaohui Li

Spatial and temporal distributions of copper, lead and zinc concentrations in tree rings along the upper Pecos River, New Mexico were investigated in this research. Spatially, the average concentrations of Zn and Pb in tree rings from contaminated sites showed elevated levels. Temporally, the concentrations of Zn and Pb in the mining area increased significantly in tree rings formed in the 1930's when the mining activity peaked. The Zn concentration declined in rings formed after the 1940's, when the mining activity ceased. However, an increase in Pb concentration continued for several decades, which could be explained by the fact that both mining activity and utilization of Pb additives in gasoline had strong effects on the Pb content in the tree rings. Spatially and temporally, little correlation was found between the Cu concentrations in the trees and the mining activity. The results from this study indicate that the contamination history in spatial and temporal dimensions can be revealed by dendrochronological analyses of tree rings using Zn and Pb as indicators.

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Bromine-Catalyzed Oxidation of Methane in the Earth's Atmosphere: An Alternate Perspective

Sujata Guha and Joseph S. Francisco

Methane is an important greenhouse gas existing in the Earth's atmosphere. High concentrations of methane lead to global warming, which poses a concern. Among other processes, the overall build-up of methane is controlled by its oxidation reaction with hydroxyl radicals. We have developed a novel scheme of methane oxidation in the atmosphere that clarifies some of the uncertainties involved in the original oxidation scheme proposed by Lary and Toumi. According to our proposition, the oxidation of methane occurs in a bromine-catalyzed cycle that results in the destruction of ozone and the production of carbon monoxide, water and oxygen molecules.

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Benthic Macro-invertebrates of River Yamuna in Delhi stretch at various levels of Physico-chemical water quality parameters

Chetna Anand*, Pratima Akolkar1 and Rina Chakravarty

River Yamuna in NCT-Delhi, from its upstream at Palla till its downstream at Okhla reservoir was selected to determine benthic macro-invertebrate fauna composition at various levels of physico-chemical water quality parameters. Monthly sampling was conducted at six locations on river Yamuna in Delhi from January 2002 to December 2002. The river in Delhi city is subjected to various anthropogenic influences which result in water quality degradation and hence change in benthic fauna composition. The study determines the ranges of the selected physico-chemical parameters for the benthic families encountered. The physico-chemical characteristics of water quality, supporting benthic macro-invertebrates, were assessed by pH, conductivity, total dissolved solids, dissolved oxygen, chemical oxygen demand (COD) and biochemical oxygen demand (BOD). Annual % abundance of benthic macro-invertebrate taxa encountered was evaluated at all the locations. Benthic fauna composition alters with change in physico-chemical characteristics of water quality. Low levels of physico-chemical parameters supported benthic families viz Caenidae & Hydropsychidae. These benthic families were replaced by families belonging to Mollusca, Hemiptera, Coleoptera, Diptera and Oligochaetes with increase in levels of physico-chemical characteristics.

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The Level of Selected Heavy Metals (Cd, Cu, Fe, Pb, Mn and Zn) at Residential Area Nearby Labu River System Riverbank, Malaysia

Lim Sun Hoo1*, Abdullah Samat1 and Mohd. Rozali Othman

A study was carried out to determine the level of selected heavy metals (Cd, Cu, Fe, Pb, Mn and Zn) at residential area nearby Labu River System riverbank between December 1999 and July 2000. Integrated approach applied was to measure the concentration of cadmium (Cd), copper (Cu), iron (Fe), lead (Pb), manganese (Mn) and zinc (Zn) in water column and to highlight potential discharge sources. Results obtained exhibited that Cd (0.022-0.042 mg/l), Cu (0.340-0.575 mg/l) and Pb (0.219-0.325 mg/l) were exceeded the Interim National Water Quality Standard (INWQS) of Malaysia threshold limits for portable water whilst Fe (0.324-0.535 mg/l), Mn (0.027-0.045 mg/l) and Zn (0.037-0.058 mg/l) respectively fall below the regulated safety values. However, based on the acceptability aspects for drinking water ruled by World Health Organization (WHO), Cd and Pb were above health-based guideline. The levels of Cu, Fe, Pb, Mn and Zn well established below permissible level for water supply. Overall findings indicated that water bodies of Labu River System required extensive treatment prior to be used as portable water. Wastewater and soluble ionic metals origins from domestics, corrosion of household piping systems and building materials, local scale open burning, impetuously use of pesticides and fertilizers in plantations, density of infrastructure networks and wet deposition were considered as main contributors to the detected level of selected heavy metals (Cd, Cu, Fe, Pb, Mn and Zn) at residential area at Labu River System riverbank.

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Oxidation of Aqueous Paranitrophenol with Ozone and Ozone/Fe (III)

Monia Guiza*, Abdelmottaleb Ouederni and Abdelhamid Ratel

The degradation of Paranitrophenol with ozone and ozone combined with iron (III) or ozone at basic pH is studied in a semi gas liquid reactor. The pH dependence and the influence of the initial concentration of iron(III) are investigated to find the optimal conditions for a complete and fast oxidation of paranitrophenol. Experimental results show that ozone reacts rapidly with paranitrophenol at high pH and we observe a catalytic effect Fe(III) in no buffered solution.

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A Significant Decrease in Colour Caused by Polyphenols with help of Nickel during Clarification Process of Cane Juice

Shweta Upadhyay and Anil Kumar Gupta

Though much work has been done in the direction of removing colour in the clarification process during sugar manufacture, but much success has yet not been achieved. In the present work, attention has been paid to decrease the amount of polyphenols which are the main cause of sugar colouration, the juice was treated with nickel pieces during clarification process near 700C, the polyphenols were found to decrease due to their reduction into cyclohexanol derivatives.

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Ionization of Sulphur Dioxide in Solutions Containing 1:1 Mixture of High Donor Number and High Dielectric Constant Organic Solvents

D. K. Sanyal, S.C.Sishi, J.M.Mofokeng and M.M. Mdleleni

Electrical conductivity of solutions increases significantly when 1 : 1 mixture of triethyl amine and acetonitrile or nitromethane are saturated with sulphur dioxide. Presence of ionic species in such solutions has been established by IR, UV-visible and GC-MS techniques. These solutions also react with certain metals and stable addition products, MSO3.xSolv, where M= Cu(II), Mg(II), Cd(II) ; x= 1-2 and Solv= coordinated organic molecules, have been isolated. An infrared study suggests that the SO3group in these adducts contain M - S coordinated sulphito form.

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Short Communication : Unnecessary pesticide applications in Northern Ireland apple orchards due to mis-identification of a beneficial mite species.

Andrew G. S. Cuthbertson

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Risk Assessment in Metropolitan Areas Polluted by Hydrocarbons

Concetta I. Giasi and Costantino Masciopinto

A Risk-Based Corrective action (RBCA) procedure has been applied to industrial area located in Southern Italy. The methodological study provides further estimation and geostatistical approach to improve the available collected data on the study area. The ground water flow was also studied under transient conditions to evaluate the effect of the mound of the water table on the washing of unsaturated contaminated soil and water contamination. Bioscreen, based on instantaneous reaction model established the spatial concentration distribution in the studied groundwater and the inactivation distance of selected contaminants from pollution sources. Model results showed a good interpretation of field data even though more detailed information is required in order to define a correct risk assessment on people health. The RBCA showed very risky conditions could be determined by mercury concentration in the shallow ground water. Remediation projects of the contaminated are strongly recommended

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Corrosion behavior of copper alloys in contaminated seawater

H. M. Ezuber

Copper alloys are used extensively in corrosive environments for numerous engineering applications and in particular as heat exchanger material in thermal power stations and in chemical industries. In this paper the corrosion behavior of different types of copper alloys, 90/10 & 70/30 cupronickel as well as 70/30 brass, are evaluated in seawater as a function of thiosulfate concentrations and test temperature. Alloy 70/30 cupronickel shows excellent resistance towards general corrosion in seawater with or without thiosulfate contaminant. The alloy, however, exhibited pitting type attack under these conditions. The intensity of the pitting attack increased with increasing thiosulfate concentration and/or seawater temperature. The results also showed that the seawater corrosion rate values of 70/30 brass alloy are higher than those of 90/10 cupronickel alloys under the same conditions of temperature and S2O32- concentrations. The seawater corrosion resistance of both alloys decreases with increasing test temperature and/or thiosulfate concentration. Polarization plots (potential-current density curves) for 70/30 brass in seawater-thiosulfate solutions exhibited general increase in anodic current density with increasing applied potential irrespective of temperature. For 90/10 cupronickel alloy, similar behavior is obtained at room temperature. At 50 or 80oC, however, the anodic plots exhibited active dissolution-passivation-pitting corrosion behavior. The repassivation is attributed to the formation of protective film on the metal surface which gives a certain degree of protection (dramatically decreasing the corrosion rate). At a certain potential, however, failures on this film occur leading to pitting corrosion. Evidence of dezincification is obtained on the 70/30 brass alloy in all test solutions. The intensity of the dezincification increases with increasing solution temperature and/or thiosulfate concentration.

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Respirometeric Study of Corn Steep Liquor

A. Rajor*, A.K. Jaggi and R.P. Garg

The respirometric technique relies upon reoxygenation of a wastewater sample through a quality controlled polyethylene membrane.The liquid sample is surrounded by polyethylene membrane permeable to oxygen and the sample is stirred in the respirometer. In studies the DO saturation concentration of the sample in the respirometer and BOD bottle was experimentally determined. The wastewater sample was prepared from corn steep solids and respirometric BOD exertion study was conducted. It was observed from the results that organic components of corn steep solids are amenable to biological oxidation provided a well-acclimatized seed used. For biological oxidation 7.8 pH is required, if it will less than 7.8 then only carbonaceous BOD will exerted.

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Short Communication : Unnecessary pesticide applications in Northern Ireland apple orchards due to mis-identification of a beneficial mite species.

Andrew G. S. Cuthbertson

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