BOD-DO modeling and water quality analysis of a waste water outfall off Kochi, west coast of India

Water quality scenarios around an offshore outfall off Kochi were simulated using MIKE21 water quality model, assuming a high Biochemical Oxygen Demand (BOD=50 mg l(-1)) effluent discharge. The discharge is introduced into the model through an outfall located at a distance of 6.8 km from the shore at a depth of 10 m. Three scenarios were simulated with different discharge rates such as 2, 5 and 10 m3 s(-1), with BOD load of 8640, 21,600 and 43,200 kg day(-1) respectively. Model simulations were carried out to estimate the assimilation capacity of the waters off Kochi for the three discharge rates. The results show that for 10 m3 s(-1) effluent discharge, the initial BOD of 50 mg l(-1) reduced to 3.33 mg l(-1) at the outfall after 48 h. High BOD values were confined to an elliptical area of approximately 8 km2 around the outfall. Based on this, the assimilative capacity of the waters off Kochi in terms of BOD can be estimated as 38,000 kg day(-1). It is suggested that offshore waters could be used as a feasible alternative to the Kochi backwaters for the disposal of treated effluent.     

Remanufacturing for the automotive aftermarket-strategic factors: literature review and future research needs

While the concepts of remanufacturing and reverse logistics are gaining popularity in practice, the available literature and theory on strategic decision making in these areas are limited. This paper is designed to address this gap, in particular, for the automotive industry aftermarket. In doing so, the authors reviewed literature pertaining to: customer demand(s), product design and development, cost-benefit analysis of reman, core (i.e., used product) supply management, reman competencies and skills, product life cycle strategies, reman and reverse logistics network design, relationships among key stakeholders, environmental considerations, regulations, and impact of emerging economies. The literature findings along with our experience in working with automotive reman products were used as inputs to guide the formulation of seven major propositions for the strategic factors in decision making within reman. The propositions were then tested through a case study. The case study reconfirmed many of the factors like product life cycle, regulations, etc. from the literature review and also identified new factors like OE customer requirements. Our results provide a foundation for further research for companies that deal with Original Equipment (OE) Sales, Original Equipment Service (OES), as well as Independent Aftermarket (IAM) business in the automotive industry.     

Cytotoxic effect of plant extract-based nanoparticles on cancerous cells: a review

Environmental Chemistry Letters - Cancer is one of the most fatal diseases causing deaths of millions of people worldwide. Since actual cancer treatments are rarely efficient and often toxic, there...     

Analysis of leachate pollution index and formulation of sub-leachate pollution indices.

An index known as leachate pollution index (LPI) for quantifying the leachate contamination potential of municipal landfills had been developed and reported by the authors. It is a quantitative tool by which the leachate pollution data of landfill sites can be reported uniformly. LPI is an increasing scale index and has been formulated based on the Delphi technique. It provides a convenient means of summarizing complex leachate pollution data and facilitates its communication to the general public, field professionals and policy makers. However, it is observed that the LPI, like any other environmental index, fails to effectively communicate the details about the strength of various pollutants/pollutant groups present. In an effort to make the LPI more informative and useful, it is proposed to divide the LPI into three sub-indices. The aggregation of these three sub-LPIs will result in the overall LPI. The formulation and the application of LPI and its three sub-indices are presented in this paper. It has been concluded that the splitting of LPI into three sub-indices provides a better insight on the strength of various pollutants and can be useful to the experts in deciding various management issues regarding leachate treatment. The leachate characteristics of a UK landfill have been used as a case study to demonstrate the calculation of three sub-LPIs and the overall LPI.     

Optimizing the position of insulating materials in flat roofs exposed to sunshine to gain minimum heat into buildings under periodic heat transfer conditions

Building roofs are responsible for the huge heat gain in buildings. In the present work, an analysis of the influence of insulation location inside a flat roof exposed directly to the sun’s radiation was performed to reduce heat gain in buildings. The unsteady thermal response parameters of the building roof such as admittance, transmittance, decrement factor, and time lags have been investigated by solving a one-dimensional diffusion equation under convective periodic boundary conditions. Theoretical results of four types of walls were compared with the experimental results available in literature. The results reveal that the roof with insulation placed at the outer side and at the center plane of the roof is the most energy efficient from the lower decrement factor point of view and the roof with insulation placed at the center plane and the inner side of the roof is the best from the highest time lag point of view among the seven studied configurations. The composite roof with expanded polystyrene insulation located at the outer side and at the center plane of the roof is found to be the best roof from the lowest decrement factor (0.130) point of view, and the composite roof with resin-bonded mineral wool insulation located at the center plane and at the inner side of the roof is found to be energy efficient from the highest time lag point (9.33 h) of view among the seven configurations with five different insulation materials studied. The optimum fabric energy storage thicknesses of reinforced cement concrete, expanded polystyrene, foam glass, rock wool, rice husk, resin-bonded mineral wool, and cement plaster were computed. From the results, it is concluded that rock wool has the least optimum fabric energy storage thickness (0.114 m) among the seven studied building roof materials.     

Heavy metals in the polychaete Glycera longipinnis from the southwest of India

Metal concentrations in sediment and in whole tissue of the benthic polychaete Glycera longipinnis collected along the southwest coast of India were analysed. Relative seasonal accumulation of metals (Cu, Pb, Cr, Ni, Zn, Cd, Hg) was studied by categorising the habitat as less polluted or highly polluted based on metal contamination routed through industrial and urban sources. The metal content in tissues varied seasonally in the ranges, Cu: 2.21–27.08 μg·g^?1, Pb: 0.06–4.92 μg·g^?1, Cr: 1.73–29.20 μg·g^?1, Ni: 1.60–4.61 μg·g^?1, Zn: 14.72–82.30 μg·g^?1, Cd: 0.04–1.38 μg·g^?1and Hg: below decetable limits to 0.86 μg·g^?1. Concentration of heavy metals was found to be high in the whole body of G. longipinnis pooled from the polluted transects. The results of this study suggest that G. longipinnis may act as a useful biological indicator for heavy metal pollution along the southwest coast of India.     

Cytogenetic results from the U.S. collaborative study on CVS

Cytogenetic data are presented for 11 473 chorionic villus sampling (CVS) procedures from nine centres in the U.S. NICHD collaborative study. A successful cytogenetic diagnosis was obtained in 99.7 per cent of cases, with data obtained from the direct method only (26 per cent), culture method only (42 per cent), or a combination of both (32 per cent). A total of 1.1 per cent of patients had a second CVS or amniocentesis procedure for reasons related to the cytogenetic diagnostic procedure, including laboratory failures (27 cases), maternal cell contamination (4 cases), or mosaic or ambiguous cytogenetic results (98 cases). There were no diagnostic errors involving trisomies for chromosomes 21, 18, and 13. For sex chromosome aneuploidies, one patient terminated her pregnancy on the basis of non-mosaic 47,XXX in the direct method prior to the availability of results from cultured cells. Subsequent analysis of the CVS cultures and fetal tissues showed only normal female cells. Other false-positive predictions involving non-mosaic aneuploidies (n = 13) were observed in the direct or culture method, but these cases involved rare aneuploidies: four cases of tetraploidy, two cases of trisomy 7, and one case each of trisomies 3, 8, 11, 15, 16,20, and 22. This indicates that rare aneuploidies observed in the direct or culture method should be subjected to follow-up by amniocentesis. Two cases of unbalanced structural abnormalities detected in the direct method were not confirmed in cultured CVS or amniotic fluid. In addition, one structural rearrangement was misinterpreted as unbalanced from the direct method, leading to pregnancy termination prior to results from cultured cells showing a balanced, inherited translocation. False-negative results (n = 8) were observed only in the direct method, including one non-mosaic fetal abnormality (trisomy 18) detected by the culture method and seven cases of fetal mosaicism (all detected by the culture method). Mosaicism was observed in 0.8 per cent of all cases, while pseudomosaicism (including single trisomic cells) was observed in 1.6 per cent of cases. Mosaicism was observed with equal frequency in the direct and culture methods, but was confirmed as fetal mosaicism more often in cases from the culture method (24 per cent) than in cases from the direct method (10 per cent). The overall rate of maternal cell contamination was 1.8 per cent for the culture method, but there was only one case of incorrect sex prediction due to complete maternal cell contamination which resulted in the birth of a normal male. The rate of maternal cell contamination was significantly higher in samples obtained by the transcervical sampling method (2. 16 per cent) than in samples obtained by the transabdominal method (0.79 per cent). From these data, it is clear that the culture method has a higher degree of diagnostic accuracy than the direct method, which should not be used as the sole diagnostic technique. The direct method can be a useful adjunct to the culture method, in which maternal cell contamination can lead to incorrect sex prediction and potentially to false-negative diagnostic results.     

Perchlorate contamination of groundwater from fireworks manufacturing area in South India

Perchlorate contamination was investigated in groundwater and surface water from Sivakasi and Madurai in the Tamil Nadu State of South India. Sensitive determination of perchlorate (LOQ?=?0.005 μg/L) was achieved by large-volume (500 μL) injection ion chromatography coupled with tandem mass spectrometry. Concentrations of perchlorate were <0.005–7,690 μg/L in groundwater (n?=?60), <0.005–30.2 μg/L in surface water (n?=?11), and 0.063–0.393 μg/L in tap water (n?=?3). Levels in groundwater were significantly higher in the fireworks factory area than in the other locations, indicating that the fireworks and safety match industries are principal sources of perchlorate pollution. This is the first study that reports the contamination status of perchlorate in this area and reveals firework manufacture to be the pollution source. Since perchlorate levels in 17 out of 57 groundwater samples from Sivakasi, and none from Madurai, exceeded the drinking water guideline level proposed by USEPA (15 μg/L), further investigation on human health is warranted.     

Spatial distribution of aerosol black carbon over India during pre-monsoon season

Aerosol black carbon (BC) mass concentrations ([BC]), measured continuously during a mutli-platform field experiment, Integrated Campaign for Aerosols gases and Radiation Budget (ICARB, March–May 2006), from a network of eight observatories spread over geographically distinct environments of India, (which included five mainland stations, one highland station, and two island stations (one each in Arabian Sea and Bay of Bengal)) are examined for their spatio-temporal characteristics. During the period of study, [BC] showed large variations across the country, with values ranging from 27 μg m^?3 over industrial/urban locations to as low as 0.065 μg m^?3 over the Arabian Sea. For all mainland stations, [BC] remained high compared to highland as well as island stations. Among the island stations, Port Blair (PBR) had higher concentration of BC, compared to Minicoy (MCY), implying more absorbing nature of Bay of Bengal aerosols than Arabian Sea. The highland station Nainital (NTL), in the central Himalayas, showed low values of [BC], comparable or even lower than that of the island station PBR, indicating the prevalence of cleaner environment over there. An examination of the changes in the mean temporal features, as the season advances from winter (December–February) to pre-monsoon (March–May), revealed that: (a) Diurnal variations were pronounced over all the mainland stations, with an afternoon low and a nighttime high; (b) At the islands, the diurnal variations, though resembled those over the mainlands, were less pronounced; and (c) In contrast to this, highland station showed an opposite pattern with an afternoon high and a late night or early morning low. The diurnal variations at all stations are mainly caused by the dynamics of local Atmospheric Boundary Layer (ABL). At the entire mainland as well as island stations (except HYD and DEL), [BC] showed a decreasing trend from January to May. This is attributed to the increased convective mixing and to the resulting enhanced vertical dispersal of species in the ABL. In addition, large short-period modulations were observed at DEL and HYD, which appeared to be episodic. An examination of this in the light of the MODIS-derived fire count data over India along with the back-trajectory analysis revealed that advection of BC from extensive forest fires and biomass-burning regions upwind were largely responsible for this episodic enhancement in BC at HYD and DEL.     

Preconcentration technique for the determination of trace elements in natural water samples by ICP-AES

A procedure was developed for the determination of Cd, Cu, Zn, Co, Ni, Mn, Pb and Mo in water samples by inductively coupled plasma atomic emission spectrometry (ICP-AES) after preconcentration on a morpholine dithiocarbamate (mor-DTC) supported by bagasse (Saccharam aphisinaram). The sorbed elements were subsequently eluted with 4,M HNO₃ and the acid eluates were analysed by ICP–AES. The influence of various parameters such as pH, flow rate of sample, eluent concentration, volume of the sample and volume of eluent were investigated to enhance the sensitivity of the present method. A 20,mL disposable syringe served as preconcentration column. Under the optimal conditions Cd, Cu, Zn, Co, Ni, Mn, Pb and Mo in aqueous sample was concentrated about 100-fold. The sorption recoveries of elements were higher than 99.6%. The method is also applied for the analysis of natural and spiked water samples.