Variations of physicochemical properties in Kalpakkam coastal waters, east coast of India, during southwest to northeast monsoon transition period

A significant variation in physicochemical properties of the Kalpakkam coastal waters, eastern part of India, was observed during the event of southwest to northeast monsoon transition. Increase in nitrate, total nitrogen, and silicate concentrations were noticed during post-transition period. Ammonia concentration was at peak during transition period as compared to pre- and post-transition periods. Hypo-saline condition (~23 psu) was observed during post-transition as the surface water salinity decreased by ~10 psu from the pre-transitional values. Turbidity, suspended particulate matter, phosphate and total phosphorous values decreased marginally, coinciding with northward to southward current reversal. A drastic decrease (eightfold) in chlorophyll-a concentration was observed in the coastal water during post-transition period.     

Modification of Soy Protein Plastic with Functional Monomer with Reactive Extrusion

Chemical modification of soy protein with monomers such as maleic anhydride, glycidyl methacrylate and styrene was accomplished using reactive extrusion technology. Thermal and mechanical properties of the modified soy protein plastics were characterized with differential scanning calorimetry (DSC), a dynamic mechanical analyzer (DMA) and a United Testing System load frame. It was found that the denaturation temperature and the glass transition temperature of soy protein plastic changed. In addition, the tensile properties of modified soy protein plastic improved. Attenuated total reflection Fourier transform infrared (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS) were used to characterize the structure of modified soy proteins. A suggestion of the interaction between soy protein and functional group in functional polymers is given. Through the in-situ interaction between the polymer and soy protein plastic, the mechanical properties of the soy protein plastic can be adjusted and controlled.     

Consequences of manganese compounds: a review

Manufacturing of manganese (Mn) compounds, their industrial applications as well as mining overburden, has generated a potential environmental pollutant. Occupational exposure to elevated levels of Mn occurs during mining, welding, smelting and other industrial anthropogenic sources. Chronic and acute exposure of this metal pollutant leads to adverse consequences and is clinically categorized by various symptoms of neurotoxicity including cognitive, psychiatric symptoms, Parkinson's disease, extra pyramidal signs, manganism, dystonia, and motor system dysfunction. The aim of this review is to summarize the possible mechanism underlying Mn compounds-mediated neurotoxicity leading to neurodegenerative diseases. Our review endeavours to examine recent advances in research on Mn-related environmental pollution, Mn-induced poisoning, molecular mechanisms underlying Mn-induced neurotoxicity with case studies as well as current approaches employed for treatment and prevention of Mn exposure.     

Natural radioactivity and radiation exposure in the high background area at Chhatrapur beach placer deposit of Orissa, India

A high natural background radiation area is reported for the Chhatrapur beach placer deposit of Orissa state, on the southeastern coast of India, due to the presence of radiogenic heavy minerals. The average activity concentrations of radioactive elements 232Th, 238U and 40K were measured by gamma-ray spectrometry using a HPGe detector, and found to be 2500 +/-1850, 230 +/- 140 and 120 +/- 35 Bq kg-1, respectively, for the bulk sand samples. The absorbed gamma dose rates in air due to the naturally occurring radionuclides varied from 375 to 5000 nGy h-1, with an average value of 1625 +/- 1200 nGy h-1. The external annual effective dose rate of the region ranged from 0.46 to 6.12 mSv y-1, with an average value of 1625 +/- 1200 mSv y-1. The absorbed gamma dose rate levels of Chhatrapur beach area were similar to the monazite sand-bearing high background radiation areas of southern and southwestern coastal tracts of India and other similar areas of the world. The major contributors to the enhanced level of radiation are monazite and zircon sands.     

Benefits of the development and dissemination of climate-smart rice: <Emphasis Type="Italic">ex ante</Emphasis> impact assessment of drought-tolerant rice in South Asia

In the era of climate change, rice (Oryza sativa L.) production is increasingly affected by the rising frequency and severity of various abiotic stresses such as flood and drought. In some cases, 100 % yield loss can be attributed solely to these stresses. Hence, there is an urgent need to develop climate-smart rice that is more resilient to abiotic stresses. As the development and dissemination of climate-smart rice varieties entail costs, this article examines the net economic benefits of developing and disseminating successful drought-tolerant rice in South Asia where rice area prone to drought far outweighs area with other abiotic stresses. Drought causes major rice yield losses not only in South Asia but also in other parts of Asia and Africa. Using the ORYZA2000 (ORYZA model series were developed at the International Rice Research Institute (IRRI) in the early 1990s in collaboration with Wageningen University and Research Centre (WUR) and 16 national agricultural research and extension systems in Asia. ORYZA2000 is an update and integration of earlier versions of the ORYZA model. More detailed documentation of ORYZA2000 can be found in (http://books.irri.org/9712201716_content.pdf)) crop growth simulation model, we demonstrate that a successful drought-tolerant rice variety can provide yield gains in South Asia of a minimum of 1.71 % to a maximum of 8.96 % when there is no change in the climate and under different climate scenarios projected by Canadian General Circulation Models (CGCMs). Moreover, our economic analysis shows that the economic benefits from the successful development and dissemination of droughttolerant rice more than outweigh the research investments needed to develop a variety. Although the research, development, and dissemination of a climate-smart drought-tolerant rice variety in the South require USD 84 million, our economic model indicates that rice production will be higher by a minimum of 6 million tons worth USD 3.3 billion, and rice prices will be lower by a minimum of USD 72 per ton when a drought-tolerant variety is adopted in South Asia (as compared to the case without this new variety). This can lead to improved rice food security and better nutritional outcomes for the poor.     

A process integration approach to industrial water conservation: a case study for an Indian starch industry

A case study for water using network of a Starch industry in the state of Gujarat, India, is undertaken with an aim to reduce demineralised water and freshwater flow rates and consequently the wastewater flow rate. The problem was identified as a multi contaminant, reuse and recycle problem. The freshwater consumption and demineralised water consumption were 100 t/h and 51 t/h respectively before modification and the network was dealing with three major contaminants such as total organic content, total dissolved solids and total suspended solids. A program was developed in MATLAB for analysis using Water Pinch. The improved water using network designed for the present work consumed less demineralised and freshwater. The reductions are of the tune of 28% and 64.38% for demineralised and fresh water respectively. Due to alteration in piping, there will be a saving of 406 026 INR per year, which will be utilized for development of efficient environment policy for the company. The entire concept had been implemented on plant level on 1st February-2009 and the reductions are of the tune of 25% and 60% for demineralised and fresh water respectively.     

An assessment of heavy metal contamination in soils of fresh water aquifer system and evaluation of eco-toxicity by lithogenic implications

The chemistry of heavy metals in sediments with respect to bio-availability and chemical reactivity is regulated by pH, texture, and organic matter contents of the sediments and specific binding form and coupled reactivity of the metals within. To focus on the metal distribution (Fe, Mn, Pb, Cd, Zn, Co, Cu, and Cr) and behavior in a fresh water aquifer system along with the ecological toxicity parameters, a four-step sequential extraction method was applied on 18 Eastern Ghats’ type sediments from fluorosis-hit Nayagarh district, India. Geo-accumulation index of metals in the sediments indicates that they are practically uncontaminated and/or less contaminated with and Fe, Mn, and Cu; contaminated to moderately contaminated with Pb, Zn, and Cr; and strongly contaminated with Cd. Rather, more than 80 % recovered Cd metal concentration in sediments constitute the labile fractions. Temporal clustering of metal fractions indicates transition metal fraction distribution claiming the sediment pH regulation. Similarly, base metal distribution accounts for organic carbon and soil conductivity due to their greater availability in exchangeable and sulfide fractions. Correlation analysis and factor analysis scores demonstrate lack of inter-relationship between transition group and base metal fractions. High fluoride concentration in ground water is associated with high sodium-bicarbonate-iron affinity with elevated pH values (i.e., >7.0) and high positive factor score with the total iron concentration in ground water.     

Leaf surface structure alterations due to particulate pollution in some common plants

The plant foliar surface is the most important receptor of atmospheric pollutants. It undergoes several structural and functional changes when particulate-laden air strikes it. In the present investigation, ten annual plant species viz., Abelmoschus esculentus, Celosia cristata, Coleus blumei, Cyamopsis tetragonolobus, Gomphrena globosa, Impatiens balsamina, Ocimum sanctum, Phaseolus vulgaris, Solanum melongena, and Zinnia elegans were studied for their growth parameters and leaf morphological features. They were subjected to dust experimentally for 60 days. The micro-morphological traits like wax, cuticle, epidermis, stomata, and trichomes were observed under light and scanning electron microscopes. Remarkable differences in the growth parameters and micro-morphological features were recorded in the dust-treated plants when compared to the respective controls. The reduction in growth parameters, the size of epidermal cells, and stomata were reduced and cuticle damage was also observed. The relative proportion of fine particles, which play a major role in hampering the overall growth of a plant, was higher in comparison to ultra-fine and coarse particles.     

A Study of Physicomechanical and Morphological Properties of Starch/Poly(vinylalcohol) Based Films

Starch/Poly(vinylalcohol) blends in two different ratios (60:40 and 50:50) were prepared with glycerol as a plasticizer. Films were cast by a solution casting method. One set of films were filled with 10 wt% of unmodified bentonite clay and another set of films were crosslinked with epichlorohydrin in an alkaline medium. The prepared film samples were subjected to X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), mechanical characterization and scanning electron microscope (SEM). Significant changes in the tensile properties were observed depending on the different chemical constituents of the films. The presence of clay and crosslinking with epichlorohydrin were both found to have considerable effect on the morphology and mechanical property of the films. The SEM investigations, XRD analysis and FTIR studies revealed the interaction between the various chemical components of the films.