Haematological,biochemical, enzymological and histological responses of Labeo rohita exposed to methyl orange dye solution treated with Oedogonium subplagiostomum AP1

Environmental Science and Pollution Research - The present investigation is an attempt to assess the impact of untreated methyl orange and Oedogonium subplagiostomum AP1 treated methyl orange dye...     

Effect of photo-biodegradation and biodegradation on the biogeochemical cycling of dissolved organic matter across diverse surface water bodies

The objective of this research was to quantify the temporal variation of dissolved organic matter(DOM) in five distinct waterbodies in watersheds with diverse types of land use and land cover in the presence and absence of sunlight. The water bodies were an agricultural pond, a lake in a forested watershed, a man-made reservoir, an estuary, and a bay. Two sets of samples were prepared by dispensing unfiltered samples into filtered samples in 1:10 ratio(V/V). The first set was exposed to sunlight(10 hr per day for 30 days) for examining the combined effect of photo-biodegradation, while the second set was stored in dark for examining biodegradation alone. Spectroscopic measurements in tandem with multivariate statistics were used to interpret DOM lability and composition. The results suggest that the agricultural pond behaved differently compared to other study locations during degradation experiments due to the presence of higher amount of microbial humic-like and protein-like components derived from microbial/anthropogenic sources. For all samples, a larger decrease in dissolved organic carbon(DOC) concentration(10.12% ±9.81% for photo-biodegradation and 6.65% ± 2.83% for biodegradation) and rapid transformation of DOM components(i.e., terrestrial humic-like components into microbial humic and protein-like components) were observed during photo-biodegradation experiments.Results suggest that sunlight facilitated DOM biodegradation, resulting in simpler recalcitrant molecules regardless of original composition. Overall, it was found that combined effects of light and bacteria are more efficient than bacterial effects alone in remineralizing and altering DOM, which highlights the crucial importance of sunlight in transforming aquatic DOM.     

A 13C NMR investigation of CO2 absorption and desorption in aqueous 2,2′-iminodiethanol and N-methyl-2,2′-iminodiethanol

The carbon dioxide capture and release from aqueous 2,2′-iminodiethanol (DEA) and N-methyl-2,2′-iminodiethanol (MDEA) have been investigated by means of ¹³C NMR spectroscopy. We have designed two experimental procedures using a gas mixture containing 12% (v/v) CO₂ in N₂ or air and 0.667 M aqueous solutions of DEA and MDEA. To understand the CO₂–amine reaction equilibria, separate experiments of CO₂ absorption (at 293, 313 and 333 K) and desorption (at boiling temperature, room pressure) were carried out. The ¹³C NMR analysis has allowed us to establish: (1) the percentage of CO₂ stored in solution as HCO₃^?, CO₃^2? and DEA carbamate; (2) the formation of DEA carbamate as a function of absorption temperature and time; (3) the slower decomposition of DEA carbamate than that of bicarbonate. In the experiments planned to test the reuse of the regenerated amines, the absorbent solution was continuously circulated in a closed cycle while it was absorbing CO₂ in the absorber (set at 293 K) and simultaneously regenerating amine in the desorber (set at 388 K). After the equilibrium has been reached (13 h), the CO₂ absorption efficiency is comprised between 84.0% (DEA) and 82.6% (MDEA) and the average amine regeneration efficiency ranges between 69.6% (DEA) and 78.2% (MDEA). Additionally, MDEA is more stable towards thermal degradation than DEA.     

Thermal Degradation and Kinetics of Alginate Polyurethane Hybrid Material Prepared from Alginic Acid as a Polyol

Alginate polyurethane hybrid materials are prepared by varying mole ratio of 2, 4-TDI as a di-isocyanate and alginic acid as a polyol in presence of dimethyl sulfoxide (DMSO) as a solvent. FT-IR and ¹³C one-dimensional (1D) solid state NMR (SSNMR) spectroscopy indicates that alginic acid is converted into alginate-polyurethane hybrid material via urethane linkage. Surface morphology of alginate-polyurethane hybrids changes by varying alginic acid: TDI ratio. The peak at near 221 °C in DSC thermogram of alginic acid (Alg) is shifted to higher temperature in alginate-polyurethane hybrid (Algpu1 and Algpu2). TGA study shows that alginate-polyurethane hybrid prepared using alginic acid: TDI = 1:1 (Algpu2) is more stable than alginic acid: TDI = 1:0.5 (Algpu1) at 300 °C. Kinetic analysis was performed to fit with TGA data, where the entire degradation process has been considered as three consecutive 1st order reactions. This study shows that thermal stability of alginate-polyurethane hybrid material was increased by adjusting mole ratio of 2, 4-TDI and alginic acid.     

Diplomacy for science: strategies to promote international collaboration

Technology innovation is an increasingly globalized exercise with dramatic consequences for scientific and diplomatic goals alike, and requires enhanced participation and integration of scientists and science-minded diplomats within diplomatic missions to advance shared policy goals. This more general problem is addressed in the present article by focusing on recent collaborations between U.S. and German scientists, including several of the coauthors.     

Biodiesel production from a free fatty acid containing Karanja oil by a single-step heterogeneously catalyzed process

Karanja oil, containing 6.2% free fatty acids (FFAs), was considered for biodiesel production using a single-step solid-phase acid catalyzed process. Different types of zeolites and Amberlyst15 catalysts were tested and biodiesel was produced. Under similar conditions, the highest biodiesel yield was achieved using an Amberlyst15 catalyst, which contained 3–5% of moisture. The effects of operating parameters of the reaction such as reaction temperature, catalyst amount, and methanol-to-oil ratio were studied. An increase of methanol:oil ratio revealed a non-monotonic increase in biodiesel yields. Similar non-monotonic behavior was observed when Jatropha oil was used. Leaching and catalyst reusability were also considered. No significant effects of leaching were observed and catalyst reusability appeared to be affected by methanol interactions. The presence of a co-solvent, Tetrahydrofuran (THF), increased the biodiesel yield. Furthermore, an optimum amount of THF (THF:methanol volume ratio of 1:2) gave rise to the highest biodiesel yield. A biodiesel yield of 93% was achieved at 120 °C using a single-step process with Amberlyst15 as a catalyst, THF as a co-solvent, and a methanol:oil ratio of 30:1.     

Selection of optimum fish oil fuel blend to reduce the greenhouse gas emissions in an IC engine—A hybrid multiple criteria decision aid approach

The increasing demand on energy due to population growth and rising of living standards has led to considerable use of fossil fuels which has in turn, had an adverse impact on environmental pollution and depletion of fossil fuels in Internal Combustion (IC) engine sector. Alternative fuel blend evaluation in IC engine fuel technologies is a very important strategic decision involving decisions balancing within a number of criteria and opinions from different decision maker of IC engine experts. The selection of appropriate source of biodiesel and proper blending of biodiesel plays a major role in alternate energy production. This paper describes an application of hybrid Multi Criteria Decision Making (MCDM) technique for the selection of optimum biodiesel blend in the IC engine. The proposed model, Analytical Network Process (ANP) is integrated with Technique for Order Performance by Similarity to Ideal Solution (TOPSIS) to evaluate the optimum blend. Here the ANP is used to determine the relative weights of the criteria, whereas TOPSIS is used for obtaining the final ranking of alternative blends. An efficient pair-wise comparison process and ranking of alternatives can be achieved for optimum blend selection through the integration of ANP and TOPSIS. The obtained preference order for the blends are as B20 > B40 > Diesel > B60 > B80 > B100. This paper highlights a new insight into MCDM techniques to evaluate the best fuel blend for the decision makers such as engine manufactures and R&D engineers to meet the fuel economy and emission norms to empower the green revolution.     

Urgency for sustainable development in coastal urban areas with reference to weather pattern,land use,and water quality

Water pollution is one of the most critical problems affecting mankind. Weather pattern and land use of catchment area have significant role in quality of water bodies. Due to climate change, there is frequent variation in weather pattern all over the world. There is also rapid change in land use due to increase in population and urbanization. The study was carried out to analyze the effect of change in weather pattern during the monsoon periods of 2008 and 2012 on water quality of a tropical coastal lake system. The nature and extent of variation in different water quality parameters namely electrical conductivity (EC), magnesium (Mg), sodium (Na), chloride (Cl), sulphate (SO₄), turbidity, Secchi disk depth, biochemical oxygen demand (BOD), phosphate (PO₄), calcium (Ca), and water temperature as well as the effect of various land use activities in the lake basin on water quality have also been studied. There is significant reduction in precipitation, EC, Mg, Na, Cl, SO₄, turbidity, and Secchi disk depths whereas a significant rise in the BOD, PO₄, Ca, and water temperature were observed in 2012. This significant reduction in electrical conductivity during 2012 revealed that because of less precipitation, the lake was separated from the sea by the sandbar during most of the monsoon period and thereby interrupted the natural flushing process. This caused the accumulation of organic matter including phosphate and thereby resulting reduction in clarity and chlorophyll-a (algae) in the lake. The unsustainable development activities of Thiruvanathapuram city are mainly responsible for the degradation of water bodies. The lack of maintenance and augmentation activities namely replacement of old pipes and periodical cleaning of pipe lines of the old sewer system in the city results in the bypass of sewage into water bodies. Because of the existence of the old sewerage system, no effort has been taken by the individual establishment/house of the city to provide their own treatment system for sewage and sullage and the untreated wastes are discharged into these old sewer pipes and ultimately the wastes reach the water bodies. In this context, decentralized treatment of sewage, sullage, and garbage by individual houses/establishments/hotels/hospitals is a better option for the developing countries. With the rapid developmental activities, and due to the variation of precipitation due to climate change, it is highly essential to provide proper waste treatment/augmentation facilities in urban lake system because a slight variation in the weather pattern can result in serious implications in the already polluted water bodies.     

Distribution of organochlorine pesticides and heavy metal residues in fish and shellfish from Calicut region, Kerala, India

Fish collected from five different locations from the Calicut region, India were analysed for the levels of organochlorine pesticides (OCPs) and heavy metal (HM) residues in order to elucidate the status of these chemical contaminants in fish and shellfish meant for human consumption. The highest concentrations of OCPs detected in the edible portion of fish were 10.47, 70.57 and 28.35 ng g-1 wet weight, in marine, brackish water and freshwater, respectively. BHC and heptachlor epoxide formed the major share of OCPs in the marine fish while BHCs contributed to the major share in the freshwater and brackish water fish. The DDT (sum of DDT and its metabolites) ranged from 0.05 to 8 ng g-1 in the samples irrespective of the habitat. Among the HMs, Cu, Zn, Mn and Cr were present in the samples irrespective of the place of collection. About 22% of the samples from the freshwater area contained marginally higher lead content above the legal limit of 0.2-0.4 microg g-1. The Cr content ranged from 0.1 to 1.1 microg g-1 in the fish with marginally higher content in the fish from freshwater and marine regions (0.55-1.1 microg g-1). Mercury was detected in the samples (55%) from marine habitat only. The concentrations of OCPs and HMs in the samples, in general, were below the maximum residual level recommended by various organizations.