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Written test was developed and administered to diagnose misconceptions in different areas of chemical equilibrium among 162 undergraduate chemistry students and 69 teachers of chemistry. Responses reveal widespread misconceptions among students and teachers in areas related to the prediction of equilibrium conditions, rate and equilibrium, applying equilibrium principles to daily life, and to acid-base and ionic solutions in water. (Author)

Explains that the news media commit fundamental errors of attribution in covering risk situations by (1) treating them as novelties, (2) failing to analyze the entire system, and (3) using insufficiently analytical language. (NKA)

Chemical reaction engineering (CRE) is vital to solve many of the pressing societal challenges—energy and energy transition, materials, food, mobility, and so forth, to meet the aspirational goals of developing country population in the face of climate change, changing demographics, and geopolitical challenges. Application of the core principles of CRE to the emerging societal challenges is creating new technologies and cost‐effective solutions by integrating the widely varied CRE activities into broad, powerful, systems descriptions with the help of interdisciplinary teams with broad expertise including chemistry, catalysis, chemical kinetics, transport phenomena, biology, applied mathematics and modeling, emerging data science technologies to design and optimize chemical/biochemical reactors. Such developments will be critical for CRE to play an important role in the emerging fourth industrial revolution—amalgamation of physical, digital, and biological worlds, where the velocity of disruption and acceleration of innovation are hard to comprehend or anticipate and such broadening of CRE discipline will be critical for the field to remain agile and relevant. This article describes some latest technical advances in Reliance Industries Ltd. using this philosophy to help achieve sustainable growth and Net Zero business targets. We will broadly discuss renewable hydrogen from novel biomass catalytic gasification, multizone catalytic cracking process to convert crude oil and low value hydrocarbon streams to petrochemical building blocks, an adsorption/desorption process for CO2 concentration and monetization from industrial flue gases. Furthermore, biotechnology advances in leveraging photosynthesis kinetics, synthetic biology, and genetic modifications for converting solar energy and carbon dioxide through algae production will be discussed to produce proteins, biomaterials, renewable biocrude, and so forth. We will also discuss new catalytic technologies to convert mixed plastic waste to stable oil and organic waste such as agri and municipal solid waste, and so forth, to biocrude for circular economy, and biodegradable plastics production to manage plastics pollution. [ABSTRACT FROM AUTHOR]

The assessment of groundwater quality is essential for the conservation of natural resources. Hence, this study aims to assess the hydrochemistry of groundwater in and around the Nagalapura Taluk in Bellary district, Karnataka, India. The groundwater quality variables are mapped using a Geographic Information System (GIS). For the hypothesis, the mean value of ten groundwater quality variables was obtained from 50 bore well samples (2016-2018). To assess the lead ions and type of water, the USSL, SAR, and Na% were measured. Ionic ratio and Gibbs graphs were used to demonstrate the chemical reactions in the water samples. ArcGIS was used for spatial analysis of the quality variables. The results showed the order of Cl- > SO42- > HCO3- with water types Na+-Cl- and Cl-, and the order of Na+ > Mg++ > Ca++ > K+ with Na+ and Mg++ as the dominant anion and cation, respectively. The hydrochemistry of groundwater is determined by the geological structure in 64 percent of the water samples examined. The Wilcox diagram shows that no-alkali exposure to the crops is expected. Forty one samples (82%) fit within the C3-S1 group; this category is fit for irrigational needs. Only 01 and 03 samples showed maximum SAR during two seasons like pre-monsoon and post-monsoon periods. The maps showed that groundwater in the selected sites is usually of higher quality, whereas the presence of dolomite indicates a reduction in water quality. [ABSTRACT FROM AUTHOR]

A comprehensive study of 58 groundwater samples collected in the virgin area of Wanaparthy watershed (1600 km2), Telangana, India, to assess the hydrochemistry, quality, water types and potability using hydrogeochemical characterization, WQI and GIS technique. Major ions concentration of Na+, K+, Ca2+, Mg2+, Cl−, F−, NO3− and SO42− in groundwater were analysed using ion chromatography (IC). Physicochemical values of the potential of hydrogen (pH), total dissolved solids (TDS) and electrical conductivity (EC) were determined using Hanna portable meters, while total hardness (TH), alkalinity and bicarbonates are estimated by titrimetric methods. Results obtained enlighten the major anions and cations, which are found in order of Cl− > HCO3− > SO42− > NO3− > F− and Na+ > Ca+2 > Mg+2 > K+ respectively. Among various ions measured, fluoride (18.97%), chloride (3.44%), nitrate (8.62%), sulphate (5.17%), sodium (34.48%) and calcium (1.72%) were found to above acceptable limit values of Bureau of Indian Standards (BIS) for drinking purposes. According to Piper trilinear diagram, two dominant hydrochemical facies, Na-Cl-SO4 and Ca-Na-HCO3 types, were identified. Gibbs diagram imparted the dominancy of samples in the territory are rock-water reaction and evaporation dominance. WQI shows 67.79% of samples pertain to the excellent to good water types reveal fit for drinking. Drainage pattern enumerated the concentration of the parameters measured are exceeding towards the downstream region, which might be due to the chemical reaction of rock-water interaction (infiltration and recharge). As the groundwater is the major source of drinking in the study area, a proper management plan has to implement before its quality deteriorated. [ABSTRACT FROM AUTHOR]

West Bengal, a significant landmass of eastern India with its varied topography, edaphic, and climatic conditions facilitates diversified forest types and conducive microhabitats for a wide array of macro-fungal wealth and the members of Aphyllophorales in particular. Detailed macro-microscopic characterizations and chemical reactions were performed to systematically identify the specimens using standard key and literatures. Six members of Aphyllophorales collected from different parts of West Bengal, India and four species belonging to the family Polyporaceae [Hexagonia tenuis (Fr.) Fr., Polyporus arcularius (Batsch) Fr., P. tricholoma Mont. and Lenzites elegans (Spreng.) Pat.] were identified, and a single species was identified under Meripiliaceae [Physisporinus lineatus (Pers.) F. Wu, Jia J. Chen & Y.C. Dai] and Meruliaceae [Bjerkandera fumosa (Pers.) P. Karst.]. The detailed description along with field and herbarium photographs, macro-morphology, and microscopic features of six species are provided in this article. [ABSTRACT FROM AUTHOR]

This paper investigates the dynamic ship berth allocation problem for a container handling port, focusing on vessel waiting time at the anchorage due to the unavailability of the berth and quay cranes. A mixed integer linear programming model considering the fuel cost associated with waiting time and operational time of the docked vessel is developed. The hiring of the quay cranes to load/unload the containers from the ship and arrangement of the vessels in different berths is taken into account. Fuel consumed by the vessels while performing their respective port operations is incorporated in the model for addressing the sustainability aspects in berth allocation problem. A chemical reaction optimization algorithm is proposed to solve the problem in a large-scale realistic environment and compared with the results with block-based genetic algorithm, genetic algorithm and particle swarm optimization. The computational experiment illustrates and validates the proposed model on a real case scenario of the port located in India. The case shows that the developed model achieves better utilization of port resources and available berths. [ABSTRACT FROM AUTHOR]

• Determined ignition temperature of fresh and old waste from an open dumpsite. • Developed correlation between moisture content and ignition temperature. • Less ignition temperature is required for old waste. • Waste smoldering time and ignition time are directly proportional to age of MSW. Open dumping of municipal solid waste (MSW) is a common practice in India which leads to a number of problems like non-uniform compaction, slope failure, percolation of water during rainy seasons, abrupt leachate generation and stability issues. It also leads to various other issues, such as manual scavenging and deliberate waste burning. During the waste degradation process, an enormous amount of heat and landfill gases (LFGs) like carbon dioxide (CO 2) and methane (CH 4) are generated. Biological and chemical reactions happening at the surface and inside the landfill contribute to the heat generation. Initiation of waste ignition is a major cause of spontaneous landfill fire. The risk posed by landfill fires is high in India as most of the landfills are non-engineered. The present study aims to determine the ignition temperature of waste dumped at Bhandewadi dumpsite located at Nagpur, India which will enable a better understanding of the initiation of fires in non-engineered landfill (surface and sub-surface fires), especially in Indian condition. The results of the present study showed that ignition temperature is directly proportional to the moisture content of MSW for its values ranging from 5 to 55% by mass. The correlation of smoldering time (Ts) and ignition time (Ti) of MSW with its age under gradual temperature rise in a muffle furnace (i.e., 3 °C/min) were also studied and it was found that Ts and Ti are directly proportional to the age of MSW and the values ranged from 23 to 34 min for Ts and 27 to 48 min for Ti. [ABSTRACT FROM AUTHOR]

Poly-β-hydroxybutyrate (PHB) depolymerase is known to decompose PHB, biodegradable polymers and therefore has great commercial significance in the bioplastic sector. However, reports on PHB depolymerases from isolates obtained from plastic-contaminated sites that reflect the potential of the source organism is scarce. In this study, we evaluated the production of extracellular PHB depolymerase from Microbacterium paraoxydans RZS6 isolated from the plastic-contaminated site in the municipal area of Shahada, Maharashtra, India, for the first time. The isolate was identified using 16S rRNA gene sequencing, gas chromatographic analysis of fatty acid methyl esters (GC-FAME), and BIOLOG method. Ithydrolyzed PHB on minimal salt medium (MSM) containing PHB as the only source of carbon. The isolate produced PHB depolymerase at 45°C during 48 h of incubation. The enzyme was purified most efficiently using octyl-sepharose CL-4B column, with the highest purification yield of 6.675 Umg-1mL-1. The activity of the enzyme was enhanced in the presence of Ca2+ and Mg2+ ions but inhibited by Fe2+ (1 mM) ions and mercaptoethanol (1000 rpm). the nzyme kinetic analysis revealed that the enzyme was a metalloenzyme; requiring Mg2+ ions, that showed optimum enzyme activity at 30°C (mesophilic) and under neutrophilic (pH 7) conditions. Scale-up from the shake-flask level to a laboratory-scale bioreactor further enhanced the enzyme yield by 0.809 UmL-1. The molecular weight of the enzyme (40 kDa), as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, closely resembled the PHB depolymerase of Aureobacterium saperdae. Our findings highlighted the applicability of M. paraoxydans as a producer of extracellular PHB depolymerase having potential of degrading PHB under diverse conditions. [ABSTRACT FROM AUTHOR]

Tropospheric NO2column (TNC) products retrieved from five satellites including GOME/ERS-2 (H, 1997–2002), SCIAMACHY (S, 2003–2011), OMI (O, 2005–2015), GOME-2/METOP_A (A, 2007–2013) and GOME-2/METOP_B (B, 2013–2015) were compared in terms of their spatiotemporal variability and changes over China. The temporal series of H suggested an increasing trend of TNC from 1997 to 2002, those of S, O and A revealed further increasing trends until the highest level of TNC was reached in 2011, but decreasing trends were detected by those of O and B from 2011 to 2015. Seasonally, TNC was the highest in winter and the lowest in summer. Variability and changes from satellite TNC products are also analyzed in different regions of China. Spatially, it was the highest in North China and the lowest in Tibetan Plateau based on five datasets. Overall, TNCs from A, B and S were higher than that from O; and TNC from S was larger than that from A at the country level. The higher TNC the region has, the larger difference satellite products would show. However, different datasets reached a good agreement in the spatial pattern of trends in TNC with highly significant increasing trends detected in North China. [ABSTRACT FROM PUBLISHER]

To sustain healthy and energetic lives of mankind clean environment and pure air are required. But with globalization, industrialization and urbanization the concept of healthy ecosystem has been demolished. Poisonous and toxic agents are mixing in the air and chemical reaction happening in the atmosphere. Twelve Indian states are studied in this paper. It explores the trends and pattern of air pollutants. Multi-linear analysis has been done to explore the association among different gases and the respiratory problems. In Jharkhand and Madhya Pradesh the number of factories has not significantly increased and also N02 and So2 are emitted less than other states. Industrially developed states have faced respiratory health problems with increasing gas emission. [ABSTRACT FROM AUTHOR]

Background: Enhydra fluctuans Lour. (Asteraceae), an edible aquatic herb, is traditionally employed against toxic effects of heavy metals in India. The present study was planned to discover the protective effect of edible extract of E. fluctuans (AEEF) against Pb toxicity. Methods: The cytoprotective role of AEEF was determined on murine hepatocytes employing MTT assay and Hoechst staining. The effects on lipid peroxidation, protein carbonylation, endogenous redox systems and the transcription levels of apoptotic proteins were studied after incubating the hepatocytes with AEEF (400 μg/ml) + Pb-acetate (6.8 μM). The defensive role of AEEF (100 mg/kg) against Pb-acetate (5 mg/kg) intoxication was measured in mice by in vivo assays. Biochemical, haematological and histological parameters, intracellular Pb burden and redox status were measured. Results: AEEF exhibited a concentration dependent cytoprotective effect against Pb-induced cytotoxicity in vitro. Pb-acetate incubation significantly (p < 0.01) altered the extents of ROS production ↑, protein carbonylation ↑, lipid peroxidation ↑, endogenous antioxidant enzymes ↓ and GSH ↓ in vitro. Besides, Pb-acetate significantly (p < 0.01) induced apoptosis in the hepatocytes apparent from the altered expressions of apoptotic proteins viz. Apaf-1 ↑, Bad ↑, Bcl-2 ↓, Cyt C ↑, cleaved caspases↑, Bid ↑ and Fas ↑. However, AEEF (400 μg/ml) could significantly (p < 0.05–0.01) attenuate the Pb-acetate mediated toxic manifestation in vitro. In in vivo assay, Pb-acetate (5 mg/kg) treated mice exhibited significantly (p < 0.01) high intracellular Pb content. A high Pb-burden within the tissues caused significant (p < 0.05–0.01) patho-physiological alterations viz. ROS production ↑, protein carbonylation↑, lipid peroxidation ↑, DNA fragmentation ↑, ATP formation ↑, mitochondrial co-enzymes Q ↓, endogenous antioxidant enzymes ↓ and GSH ↓ within the selected tissues. The haematological and serum biochemical parameters were significantly (p < 0.05–0.01) different in the Pb-acetate treated mice. Finally, histological assessment imposed significant toxic occurrence within the organs of Pb-intoxicated animals. However, concurrent administration of AEEF (100 mg/kg) could significantly (p < 0.05–0.01) reinstate the Pb-acetate mediated toxicity. Conclusion: Presence of metal chelators and phyto-antioxidants within AEEF would offer overall protection through promoting Pb clearance coupled with restoring redox balance. [ABSTRACT FROM AUTHOR]

The oxidation efficiency of atmospheric SO 2, measured as a molar ratio of SO 4 2 − to total SO x (SO x = SO 2 + SO 4 2 − ), referred as S-ratio, have been studied from a high altitude site (Gurushikhar, Mt. Abu: 24.6° N, 72.7° E, 1680 m ASL) in a semi-arid region of western India. A global 3-dimensional Chemical Transport Model (CTM), GEOS-Chem (v8-03-01), is employed to interpret the observed patterns. The S-ratios derived from time series SO 2 and SO 4 2 − measurements exhibited a pronounced seasonality, with relatively low ratios in Feb–Mar 2010, high ratios in Nov–Dec 2009 and intermediate values in Sep–Oct 2009. The lower S-ratios for Feb ‘10 and Mar ‘10 (median values 0.10 and 0.08 respectively) have been attributed to the relatively high planetary boundary layer (PBL) heights – to reduce the SO 2 loss from the atmosphere via dry deposition – as well as the lower OH radical levels and low ‘aged air mass influx’ during these months. On the other hand, low PBL heights and significant long range transport contributions are projected to be the possible causes for the higher S-ratios during Nov ‘09 and Dec ‘09 (median values 0.30 and 0.28 respectively). The seasonal patterns for the S-ratios predicted by the CTM for the GEOS-Chem 4° × 5° grid cell containing the sampling site showed highest ratios in Jul–Aug, and the lowest in Apr. The model has been employed further to study the contributions from various parameters to the S-ratios such as PBL, OH, RH, dust load, transport pattern and dry deposition. Sensitivity simulations showed the S-ratios enhancing with dust load with the peak in May (∼4.7% (median)). Similarly, the ‘dry deposition’ is seen to boost the S-ratios with the peak in August (∼66.3% (median)). Also, model simulations to assess the ‘altitudinal dependence of S-ratios’ have revealed a pronounced seasonal behaviour. [ABSTRACT FROM AUTHOR]

The early to upper Cretaceous period, after Gondwana period, was the turning point, which continued up to middle Miocene and/or Pliocene epoch in the stratigraphic history of Peninsular India, covering the Indian shield as well as its margins. Due to creation of new low marine basins in graben-and-horst structures, the preservation of the in-situ as well as continental organisms along with rocks of petroliferous basins with their rich fossil fuel, in this country could be possible. The marine organisms flourished on the palaeocoastal river, distributor and braided channels, whereas the terrestrial plants related to angiosperms, gymnosperms and pterodophytes flourished on the swampy uplands banks, point bars and delta front areas. Over geological time, all these areas which fell within area of the low marine basin were converted into prospecting areas for oil and gas. The oil must have generated, over great length of geological time by biological conversions and chemical reactions induced by high pressure and optimum temperature. The gas must have generated from humic palynofacies and minor sapropelic components by thermal cracking. Any oil buried deeper is converted into gas by thermal cracking. The petroleum deposits marked on the basis of this theoretical model are making identical pattern of occurrences with those marked on the basis of detailed investigations by ONGC, and OIL. They are falling more-or-less on three lines drawn from the palaeo mouth of the river in the triangular area of all petroliferous basins. The new petroleum deposits, marked by cross-points on the geological maps of all available palaeocoastal river low marine basins and marginal area of palaeocontinental shelf of India, based in this theoretical model, can be investigated and explored. This picture of petroleum deposits that were generated from marine and terrestrial organisms in marine sedimentary basins is in agreement with all the observational evidence that we have today. [ABSTRACT FROM AUTHOR]

Abstract: The paper describes behavior of surface ozone, its precursor gases, BC along with TOCC, TWVC, AOT1020nm as well as UV and IR radiation intensities observed during the partial solar eclipse of 15th January, 2010 over Udaipur, where 52% solar disc is obscured due to the moon’s shadow. During the beginning to main eclipse phase, the deviation values of several air pollutants concentrations from eclipse to control day values vary in a small range from −9 to −2ppb in case of surface ozone and −180 to −80 ppb for CO. The corresponding change in the values of BC observed from −3.3 to −.5μg/m3. No significant change is found in NO2, NO or in ratio of NO2/NO values during the partial eclipse time. TOCC values decrease from 3 to 5DU along with a reduction in UV radiation intensity from 20 to 35% from starting to the main eclipse phase. The AOT1020nm values are found to increase from .2 to 1.0 along with a reduction in IR radiation intensity order of 50%. However, TWVC values decrease from .22 to .1cm during the eclipse hours. The low level of dilution in surface ozone in eclipse period may be attributed with change in local atmospheric boundary layer dynamic conditions or limited air pollutants dispersion, in term of decreases in planetary boundary layer height, wind speed and hence ventilation coefficient in the same eclipse hours. Thus, present studies support the argument for the leading roles of photochemical reactions with its precursor gases under presence of solar radiation in surface ozone variability. Other possible controlling factors are advection of air pollutants from the polluted region as evident from backward wind trajectories and altering the local meteorological conditions. [Copyright &y& Elsevier]

Medicinal plants are source for a wide variety of natural antioxidants. Dietary antioxidant consumption may be an important approach for inhibiting or delaying the oxidation of susceptible cellular substrates and thus is relevant to disease prevention in many paradigms. Murraya koenigii is one of the important medicinal herb which is used as a food ingredient across India. In this study, we demonstrated the reducing power, total antioxidant potential, radical scavenging capabilities and α-glycosidase inhibitory property of different crude extracts of curry leaves (Murraya koenigii L.). The extracts were evaluated for their radical scavenging activities by means of DPPH, NO, •OH, O2- and anti-lipid peroxidation assays. In addition, extract of M. koenigii were tested for α-glycosidase inhibitory property. The extracts of M. koenigii scavenged radicals effectively in varied degree. Similarly, the total reducing power of alcohol extract was found higher in both phosphomolybednum and FRAP methods. In vitro assay of α-glucosidase activity of MKA and MKW showed an IC50 of 174.74 and 287.00 μg/ml respectively, while other two extracts did not show any significant effect. Simultaneously, total phenolic and total flavonoid contents of extracts were studied, where values of MKW were found to be higher than that of other extracts. In present study, we found that MKA and MKW extracts contain effective antioxidant and radical scavenging activities as compared to other extracts. Our study provides a proof for the ethno-medical claims and reported biological activities that curry leaves have significant therapeutic potential. [ABSTRACT FROM AUTHOR]

Abstract: There is a vital need to understand details of the methylisocyanate (MIC) release that occurred at the 1984 Union Carbide Ltd. pesticide plant in Bhopal, India in order to avoid or respond to such releases in the future. However, we believe there are serious deficiencies in currently available dispersion predictions of the impact of toxic materials on humans and animals downwind of the plant. Specifically, cloud densities have been underestimated due to failure to account for the presence of a liquid/solid aerosol that would have been produced by the chemical reactions that caused the problem. Using data reported in Union Carbide''s own investigation of the accident, which included chemical reaction data, we estimated aerosol compositions and cloud densities, then modeled the Bhopal release, simulating potential exposure levels at various locations under a number of wind-condition scenarios. For the worst-case (low wind speed and high aerosol densities), our predicted MIC concentrations at ground level are at least one order of magnitude greater than any previously published estimates. The centerline elevation of the jetting plume released at 33m elevation is predicted to rise to about 41m before falling, resulting in a 40ppm (Immediately Dangerous to Life or Health, IDLH) concentration contour that reaches the ground at about 410m downwind of the release location. This is consistent with observations that the plant environs were not hard-hit while the public immediately downwind of the plant perimeter was severely exposed. Concentrations on the order of 1000ppm are predicted at some ground-level locations, which are more consistent than previous estimates with the reported large numbers of deaths and injuries of humans and animals. [Copyright &y& Elsevier]

Abstract: The inner shelf off west coast of India, is covered with late Holocene to recent organic rich, silty-clay dominant sediments. High TOC content and sedimentation rates result in high sulfate reduction rates in this region (Mazumdar et al., 2009). In the present study, we have investigated the nature of pyrite and C–Fe–S geochemistry in a sediment core (covering the last 378years) at a water depth of 17m off Goa, west coast, India, to understand the diagenetic and palaeoclimatic/oceanographic processes. The chromium reducible sulfur (CRS) and highly reactive iron (FeHR) profiles show significant fluctuations and a negative correlation with δ34SCRS, which is attributed to relative availability of highly reactive and less reactive iron bearing minerals close to the sediment water interface. Low δ34SCRS corresponding to high CRS content characterizes early diagenetic pyritization near the sediment-water interface, whereas high δ34SCRS and low CRS content indicate late diagenetic pyritization of less reactive iron during burial. High OBS/CRS ratios suggest the important role played by the labile organic compound in binding sulfur in the sediment. Partitioning of stable sulfur isotopes into organic and iron bound phases is apparently linked to FeHR and labile organic matter availability. We have proposed FeHR profile and FeHR/FeT ratios as a potential tool to understand runoff/monsoonal fluctuations in a shallow marine depositional setting. To develop this tool into a potential paleoclimatic/oceanographic proxy and to link it to other proxies within a chronological framework, needs high resolution sampling and age dating. [Copyright &y& Elsevier]

Tritium content in air moisture, soil water, rain water and plant water samples collected around the Kaiga site, India was estimated and the scavenging ratio, wet deposition velocity and ratio of specific activities of tritium between soil water and air moisture were calculated and the results are interpreted. Scavenging ratio was found to vary from 0.06 to 1.04 with a mean of 0.46. The wet deposition velocity of tritium observed in the present study was in the range of 3.3E−03 to 1.1E−02 m s−1 with a mean of 6.6E−03 m s−1. The ratio of specific activity of tritium in soil moisture to that in air moisture ranged from 0.17 to 0.95 with a mean of 0.49. The specific activity of tritium in plant water in this study varied from 73 to 310 Bq l−1. The present study is very useful for understanding the process and modelling of transfer of tritium through air/soil/plant system at the Kaiga site. [ABSTRACT FROM PUBLISHER]

Abstract: This study presents the results of one of the first systematic experiments on tritium (3H) concentrations in ground level air against that in rainwater near a pressurized heavy water reactor in a tropical region. The samples were collected over the rainy season of three years (2007, 2008 and 2010). For this study, 31 data sets were collected and interpreted based on the theoretical information available in the literature. The specific activity ratio of 3H between rainwater and air moisture at ground level was calculated for each data set. The average specific activity ratio was found to be 1.96 ± 2.72. A correlation (r = 0.82, p < 0.001) was observed between the total rain hours in a day and the rainwater 3H activity. Higher rain duration with slower rain rate yielded higher 3H concentrations as more time was available for the scavenging/wash out process to take effect together with lower dilution. The present data also suggested the need to further investigate the influence of raindrop distribution and other local meteorological parameters on the 3H wash out process. An attempt was also made to predict the 3H concentration in air moisture samples using a Gaussian plume dispersion model and the values were compared with the measured 3H activity. The measured values were generally lower than the predictions. [Copyright &y& Elsevier]

Abstract: Sapindus mukorossi Gaertn. (Sapindaceae) is commercially an important plant much valued for its fruits commonly known as soap nut as well as for the seed oil used as a feed-stock for biodiesel production. Molecular polymorphism, determined, using three single primer amplification reaction (SPAR) methods (RAPD, DAMD and ISSR) is used to assess the genetic variability in 69 accessions of S. mukorossi Gaertn., encompassing different geographical regions in India. Cumulative band data generated using the three SPAR methods resulted in 82.49% polymorphism across all genotypes of S. mukorossi Gaertn. UPGMA tree showed two major clusters that were in accordance with the geographical diversity. The intra-population genetic diversity (0.16), Shannon information index (0.24) and polymorphic loci (45.62%) were highest in AS population, while the corresponding lowest values were recorded in HP population. The inter-population average distance ranged from 0.05 (GA and HP) to 0.26 (AP and HP). Based on these distances, the UPGMA tree for the populations was computed, which showed the presence of two major clusters. Cluster I contained all the populations from Himachal Pradesh (HP) and Uttarakhand (GA and KU) and cluster II grouped the populations from North Eastern region (AS, AP, MG). The present study showed that SPAR methods are informative and useful to unravel the diversity among different populations of the soap nut plants and is a prelude for further utilization of promising and genetically divergent materials in the breeding programmes. [Copyright &y& Elsevier]

The origin of chemical and mineralogical heterogeneity in tens-of-microns wide layers and domains in enderbite-hosted couple-of-centimeters wide pseudotachylite vein is examined based on the results of BSE and X-ray element imaging, and electron probe microanalyses of major elements of host-rock minerals, clasts, microphenocrysts, and pseudotachylite matrix. The pseudotachylite layers and domains containing variable proportions of orthopyroxene and magnetite microphenocrysts continue as mantles around quartz, K-feldspar, plagioclase and garnet clasts. The clasts are chemically modified along margins and intra-clast pseudotachylite injections. The chemical modifications are extensive in smaller clasts <5 μm diameter. At least three chemically distinct layers and domains in the pseudotachylite, and their fine-grained matrices, plot in sharply defined, well-segregated and non-overlapping fields in FeO + MgO−AlO-SiO, FeO-CaO-MgO and CaO-NaO-KO and FeO vs. FeO/FeO + MgO diagrams. The compositions of the layers and domains-smeared between a feldspar + quartz component and a ferromagnesian component of garnet + Fe-Ti oxides (±orthopyroxene)-possibly correspond to fractionated quenched melts, or admixtures of microphenocrysts that cannot be resolved by the microbeam techniques employed. The compositional variations are incompatible with deformation-driven crystal fractionation in melt. Instead the layers and domains possibly are crystal-melt mushes produced by syn-deformation ultra-high temperature (1,250-1,375°C) melting reactions involving variable proportions of host-rock minerals determined by time-transient local phase aggregates experiencing strain. The similar element variation trends in pseudotachylite examined here and those reported from anorthosite, metapelite and charnockite elsewhere suggests local phase aggregate controlled multi-reaction melting is a phenomenon commoner than hitherto realized in pseudotachylites. [ABSTRACT FROM AUTHOR]

This article deals with a systematic hydrochemical study carried out in coastal aquifers, Tuticorin, Tamil Nadu, to assess groundwater quality. A total of 29 groundwater samples were collected and analyzed. Results showed that total dissolved solids (TDS), sodium (Na), magnesium (Mg), chloride (Cl), and sulfate (SO $_{4}^{\,\,2-}$) significantly damaged groundwater systems. The degree of salinization due to seawater mixing in a well or a given area could be indicated by an increase in nearly all major cations and anions. Toxic elements (i.e., Pb and As) were higher than the maximum permissible limits of drinking water. Cross plot of HCO $_{3}^{\,\,-}$/Cl (molar ratios) versus TDS indicated that about 62% of the analyzed samples were saline. Factor analysis showed that groundwaters, affected by seawater intrusion/industrial activity, were separated from the clusters. An attempt was made to identify the hydrochemical processes that accompany current intrusion of seawater using ionic changes. It was estimated that the mixing rate of seawater intrusion was about 5.81% during April 2007. An index, called 'Seawater Mixing Index' (SMI), was also adopted and its value was SMI > 1.18 with EC > 3,000 μS/cm about 62% of the sampled waters, were saline. Further, a few trace elements (i.e., Sr, B, and Li) were used as indicators for responding to the change in fresh to saline groundwater environments in coastal aquifers. [ABSTRACT FROM AUTHOR]

Abstract: Ceria (CeO2) and india (In2O3) represent two of the most important metal oxide systems for catalytic and optoelectronic applications, respectively. Here, we report analytical interatomic potential models for these two materials, which reproduce the materials structural, elastic and dielectric properties. The potential models are then applied to study the fundamental defect reactions occurring in these materials. Further, we focus on the mechanisms of oxygen diffusion through the lattice, arising from anion Frenkel-pair formation, which is of particular interest for understanding the processes involved in radiation damage and catalysis. The thermodynamic barriers associated with the formation of the first stable anion Frenkel-pairs are 5.80eV and 4.81eV in cerium dioxide and indium sesquioxide, respectively; while for recombination, we calculate barriers of 0.78eV and 0.23eV. The threshold displacement energy for radiation damage in ceria is found to be 35.4eV, in excellent agreement with recent experimental measurements, while for india we predict a value of 14.2eV. [Copyright &y& Elsevier]

We present the field measurements of surface ozone (O3) made across the coast in five locations at three stations Poombuhar (11.14° N, 79.9° E), Tranquebar (11° N, 79.9° E) and TR Pattinam (10.46° N, 79.9° E) along the west coast of the Bay of Bengal, India in December 2000 and 2002 and in April 2001 and 2003. Measurements show a higher concentration of surface O3 up to 4.0-6.9 parts per billion by volume (ppbv) at the coastline as compared to the concentration of surface O3 at a distance 20 km inland. The higher coastline O3 concentration is attributed to the short-lived chlorine species with a lifetime of less than 10 minutes generated from the chemical reaction of sea salt particles. Mean O3 concentration decreases inland with distance from the coastline. Furthermore, the greatest difference between the coastline surface O3 concentration and O3 concentration 20 km inland was 4.8-6.4 ppbv, observed at 10 h in the morning, which is related to the morning peak of chlorine molecule (Cl2) concentration. Measurements of nitrogen dioxide (NO2) show concentrations between 4 and 10 ppbv, which are substantially higher than the critical limit of surface O3 production. [ABSTRACT FROM AUTHOR]

Abstract: Out of various non-edible oil resources, Jatropha curcas oil (JCO) is considered as future feedstock for biodiesel production in India. Limited work is reported on the kinetics of transesterification of high free fatty acids containing oil. The present study reports the results of kinetic study of two-step acid base catalyzed transesterification process carried out at an optimum temperature of 65 °C and 50 °C for esterification and transesterification respectively under the optimum methanol to oil ratio of 3:7 (v/v), catalyst concentration 1% (w/w) for H2SO4 and NaOH. The yield of methyl ester (ME) has been used to study the effect of different parameters. The results indicate that both esterification and transesterification reaction are of first order with reaction rate constant of 0.0031min−1 and 0.008min−1 respectively. The maximum yield of 21.2% of ME during esterification and 90.1% from transesterification of pretreated JCO has been obtained. [Copyright &y& Elsevier]

Precipitation is the best scavenger for the particulates and dissolved gaseous pollutants present in the atmosphere. The chemical composition of precipitation is dominated by a number of in-cloud and below-cloud scavenging processes. The present study is aimed at analyzing the chemical composition of rainwater in the relatively less industrialized part of Mumbai. The pH of rainwater in this region ranges from 4.8 to 6.4. The percentage contributions of ions were calculated and the major contributing ions were calcium (28%), chloride (23%), sodium (18%), sulfate (14%), magnesium (11%), ammonium (4%), potassium (1%), and nitrate (1%). The correlation coefficient is highest for Na and Cl ( r2 = 0.99), giving a clear indication of contribution from sea salt. Sulfate and nitrate ions also show a very good correlation ( r2 = 0.90), which may be due to their coemission from fossil fuel combustion. Acidification caused by these ions is neutralized by Ca, Mg, and NH4 ions. The neutralization effect due to these ions is validated by calculating the neutralization factor (NF). The NF values are in the order Ca > Mg > NH4. The major source contributors for the ions in precipitation are sea salt (Na, Cl, and K) and fossil fuel combustion (SO4 and NO3). These assumptions are supported by the values of wet-only ratio, enrichment factor, and percent sea salt fraction. [ABSTRACT FROM AUTHOR]

The accurate predictions of ground ozone concentrations are required for proper management, control, and making public warning strategies. Due to the difficulties in handling phenomenological models that are based on complex chemical reactions of ozone production, neural network models gained popularity in the last decade. These models also have some limitations due to problems of overfitting, local minima, and tuning of network parameters. In this study, the predictions of daily maximum ozone concentrations are attempted using support vector machines (SVMs). The comparison between the accuracy of SVM and neural network predictions is performed to evaluate their performance. For this, the daily maximum ozone concentration data observed during 2002–2004 at a site in Delhi is utilized. The models are developed using the available meteorological parameters. The results indicated the promising performance of SVM over neural networks in predicting daily maximum ozone concentrations. [ABSTRACT FROM AUTHOR]

Various physico-chemical parameters, including fluoride (F−), were analyzed to understand the hydro-geochemistry of an aquifer in a semi-arid region of India. Furthermore, the quality of the shallow and deep aquifer (using tube well and hand pumps) was also investigated for their best ecological use including drinking, domestic, agricultural and other activities. Different multivariate techniques were applied to understand the groundwater chemistry of the aquifer. Findings of the correlation matrix were strengthened by the factor analysis, and this shows that salinity is mainly caused by magnesium salts as compared to calcium salts in the aquifer. The problem of salinization seems mainly compounded by the contamination of the shallow aquifers by the recharging water. High factor loading of total alkalinity and bicarbonates indicates that total alkalinity was mainly due to carbonates and bicarbonates of sodium. The concentration of F− was found more in the deep aquifer than the shallow aquifer. Further, only a few groundwater samples lie below the permissible limit of F−, and this indicates a risk of dental caries in the populace of the study area. The present study indicates that regular monitoring of groundwater is an important step to avoid human health risks and to assess its quality for various ecological purposes. [ABSTRACT FROM AUTHOR]

The aim of the present study was to monitor adverse drug reactions associated with antihypertensive drugs. The study was conducted in medicine out patient department of 150-bed Majeedia Hospital at Hamdard University Campus in New Delhi. The study was conducted by way of one to one patient interview by a registered pharmacist using a questionnaire-based Adverse Drug Reaction Monitoring Form drafted according to the World Health Organisation Monitoring Guidelines. A total of 34 adverse drug reactions were observed in 250 hypertensive patients during the four month study. A high percentage of adverse drug reactions occurred in middle aged and female patients. Of the 34 adverse drug reactions, 18 (52.9%) were mild, 14 (41.2%) moderate and only 2 (5.8%) were classified as severe. Combination therapy was associated with significantly high occurrence (P < 0.05) of adverse drug reactions, with a total of 21 (61.8%) as compared to monotherapy (n=13, 38.2%). Cardiovascular adverse drug reactions constituted a major component, followed by gastrointestinal and respiratory complaints. Beta-blockers were the drug category associated with majority of adverse drug reactions, followed by angiotensin-converting enzyme inhibitors and calcium channel blockers. The above pharmacovigilance study presents the adverse drug reaction profile of antihypertensive medicines prescribed in our University Teaching Hospital. It was concluded that calcium channel blockers were the most frequently prescribed drug category but beta blockers were associated with higher frequency of adverse drug reactions. [ABSTRACT FROM AUTHOR]

Seven indigenous tree species of northeast India were pyrolyzed at temperatures ranging from 300°C-800°C with two different heating rates, 3°C/min and 20°C/min, and the effect of heating temperature and heating rate on the products yield and char quality were analyzed and discussed. Among all the species, E. acuminata, M. bombycina and Q. griffithii were found to yield higher percentages of char with better quality, whereas A. lucida yielded the highest percentage of tar. [ABSTRACT FROM AUTHOR]

In the management of water resources, quality of water is just as important as its quantity. In order to know the quality and/or suitability of groundwater for domestic and irrigation in upper Gunjanaeru River basin, 51 water samples in post-monsoon and 46 in pre-monsoon seasons were collected and analyzed for various parameters. Geological units are alluvium, shale and quartzite. Based on the analytical results, chemical indices like percent sodium, sodium adsorption ratio, residual sodium carbonate, permeability index (PI) and chloroalkaline indices were calculated. The pre-monsoon waters have low sodium hazard as compared to post-monsoon season. Residual sodium carbonate values revealed that one sample is not suitable in both the seasons for irrigation purposes due the occurrence of alkaline white patches and low permeability of the soil. PI values of both seasons revealed that the ground waters are generally suitable for irrigation. The positive values of Chloroalkaline indices in post-monsoon (80%) and in pre-monsoon (59%) water samples indicate absence of base-exchange reaction (chloroalkaline disequilibrium), and remaining samples of negative values of the ratios indicate base-exchange reaction (chloroalkaline equilibrium). Chadha rectangular diagram for geochemical classification and hydrochemical processes of groundwater for both seasons indicates that most of waters are Ca–Mg–HCO3 type. Assessment of water samples from various methods indicated that majority of the water samples in both seasons are suitable for different purposes except at Yanadipalle (sample no. 8) that requires precautionary measures. The overall quality of groundwater in post-monsoon season in all chemical constituents is on the higher side due to dissolution of surface pollutants during the infiltration and percolation of rainwater and at few places due to agricultural and domestic activities. [ABSTRACT FROM AUTHOR]

The mixing ratios of surface O3 were measured at St. John's College, Agra, an urban and traffic influenced area for the period of 2000–2002. The monthly averaged O3 mixing ratios ranged between 8 to 40 ppb with an annual average of 21 ppb. Strong diurnal and seasonal variations in O3 mixing ratios were observed throughout the year except for monsoon season. The mixing ratios of O3 follow the surface temperature cycle and solar radiation (r = 0.72 and r = 0.65 with temperature and solar radiation, respectively). Concentrations were higher with winds associated with NE and NW direction indicating the impact of pollution sources on surface O3 concentration. Exceedance of ozone critical level was calculated using the AOT 40 index and found to be 840 ppb.h and 2430 ppb.h for summer and winter seasons, respectively. The present O3 exposures are lower than the critical level of O3 and suggest that the present level of O3 does not have any impact on reduction in crop yields. [ABSTRACT FROM AUTHOR]

The results of the seasonal analysis of the chemistry of rain, fog and surface water of central India for the two years: June 1996 to May 1998 are presented. A total of 636 rain water samples, 146 fog water samples and 226 surface water samples of 8 locations: namely, Ambikapur, Baikunthpur, Korba, Bilaspur, Raipur, Bhilai, Dallirajhara and Kanker, from different sites were collected for the present study. This paper documents the occurrence of acidic rain and fog events and their effect on surface water pH and aquatic life in central India. Most of the rain and fog water samples collected from Baikunthpur and Korba sites were found to be acidic in nature (i.e. pH < 5). The volume weighted mean pH of rain and fog water samples of these sites was 4.8 and 4.4 with lowest pH 4.4 and 4.0, respectively. However, samples from Ambikapur, Bilaspur, Raipur and Bhilai were slightly acidic and their pH values were always around 5.8. One reservoir (mean pH 5.8) and two stop dams (mean pH 4.4 and 4.2) in Baikunthpur area were found to be acidic. The effect of acidification of water on metal-accumulation in muscles of fishes was studied. Concentrations of Al, Hg, Mn, Cd and Pb were higher in fish from acid, than from less acid waters. Causes of acidification of the atmospheric water and surface water are critically discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fertile ferro-carbonatite generated from multiphase immiscibility of magma. • REE mineralization mainly occurred during the late stage of hydrothermal evolution. • Magmatic residual volatiles rich fluids brought REE and SiO 2 into overprinted rocks. • REE fluorocarbonate(FC) Variants attributed to F− & Ca2+ or CO 3 2− activity changes. • Fluocerite coexist with FC at high F−/low CO32− depending on P-T and Ca2+ activity. • Ambadongar complex is having a high potential for REE production in India. Carbonatites and associated alkaline rocks are the primary sources for REE mineralization. The Ambadongar Carbonatite Complex (ADCC) from NW Deccan Volcanic Province (DVP) constitutes the largest Carbonatite Associated REE Deposits (CARD) in India. ADCC belongs to the final stages of the Late Cretaceous alkaline-carbonatite magmatism associated with main Deccan basalt volcanic activity. The ADCC is an envisioned diatreme structure in which four carbonatitic phases are recognized, mainly calcio-carbonatites and ferro-carbonatites. Each successive carbonatite phase shows higher REE enrichment. The primary REE mineralization with bastnäsite as the dominant REE phase is hosted by pervasive hydrothermally altered ferro-carbonatite plugs. The secondary mineralogy formed with barites in the main orebody during late- to post-magmatic hydrothermal fluid alteration is fluorite, quartz, ankerite, and other REE-bearing minerals like bastnäsite, parisite, synchysite, strontianite, florencite, monazite and columbite. Carbonatite samples contain 18.61% to 52.42% of CaO, and the LOI varies from 5.28% to 38.79%. Most can be classified as calcio-carbonatites. Since all the samples also contain an appreciable amount of Fe 2 O 3 (4.13% to 20.20%) and MnO (0.07% to 5.46%), some may be classified as ferro-carbonatites. Total REE content varies from 0.6 to 4%, with a high Ce concentration and LREE/HREE ratio. The highest values for La, Ce, Pr, and Nd are 1.95%, 1.56%, 0.16%, and 0.45%, respectively. Metasomatism of SCLM from asthenospheric melts followed by the low degree partial melting of the SCLM region is responsible for fertile carbonatite generation in ADCC. The multiphase liquid immiscibility of carbonatite melts from carbonate-silicate magma followed by immiscibility of REE rich carbonatite melt and REE deficient fluoride-rich aqueous fluids explain the higher level of REE enrichment in each successive phases of carbonatites in ADCC. The mineralizing fluids were probably the result of residual magmatic volatiles that brought mainly REE and later SiO 2 into the overprinted rocks. Ambadongar carbonatites' stable isotopic compositions agree with a magmatic origin (δ13C = −4.1 ± 1.9‰ [PDB] and δl8O = 10.3 ± 1.7‰ [SMOW]). The C–O stable isotopic modeling indicates re-equilibration under hydrothermal conditions between 180 °C and 70 °C. Significant amounts of REE fluorocarbonate minerals, relatively Sr- and Th-rich, were deposited during re-equilibration. The REE fluorocarbonate bastnäsite-(Ce) occurs as late individual crystals, overgrown on the synchysite and parisite polycrystals. Textural and chemical reactions between the REE fluorocarbonates provide insights into rare-earth elements' mobility during fluid-rock interaction. Early crystallization of synchysite/parisite indicates the high activity of Ca2+, OH−, (SO 4)2−, Al and Si in the fluid. Later, the fluid was characterized by increased activity of F−, (SO 4)2−, REE and Si, and decreased activity of Ca2+ as reflected in the association of barite, fluorite, quartz, and bastnäsite typical of strongly overprinted ferro-carbonatites. Re-equilibration and recrystallization of the primary minerals in the presence of OH−, (SO 4)2−, F−, REE, Al, and Si carried in solution by the hydrothermal fluid is the leading cause behind the refixing of REE in the form of REE fluorocarbonate in REE rich ferro-carbonatites. [ABSTRACT FROM AUTHOR]

The article investigates the protective role of free radical scavengers in copper-induced oxidative stress in Scenedesmus bijugatus by researchers from Hyderabad, India. Copper (Cu) is a bioelement and essential for metabolism. However, it is toxic at high concentrations and Cu salts are popular algicides. Hence, the mechanisms of toxicity and tolerance acquired by algae are of considerable significance. In this study, degradation of chlorophyll A and lipid peroxidation were investigated as parameters of Cu toxicity. Scenedesmus bijugatus, a green alga, was chosen as the experimental material to conduct laboratory toxicity bioassays.

The article studies photochemical transformation of the fungicide chlorothalonil, otherwise known as 2,4,5,6-tetrachloroisophthalonitrile, using ultraviolet radiation by researchers from West Bengal, India. Several studies on the photochemical transformation of different organic solvents have been reported, but no attempt has been made to evaluate the toxicity of the transformed products. This study has been intended to reinvestigate the transformation of chlorothalonil in alcohols under ultra violet irradiation for evaluation of the relative toxicity of the transformed products formed under the process.

Fenugreek (Trigonella foenum-graecum) is an annual herb, used as a spice and traditionally as medicine. Fenugreek finds its uses in treating hyperglycemia, hyperlipidemia and disorders of gastro-intestinal and cardiovascular systems. Fenugreek cultivation in India is affected by fungal diseases like root-rot and damping-off and fungicides like carbendazim are used to overcome these infections. Fungicides play both positive and negative role in plants; fungicides protect plants from diseases and also exert oxidative stress simultaneously. This report is on the response of antioxidants, superoxide dismutase and catalase in fenugreek seeds and plants treated to different concentrations of carbendazim. [ABSTRACT FROM AUTHOR]