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We conducted simultaneous real-time measurements for particles on the premises of four schools, two of which were naturally ventilated (NV) and two mechanically ventilated (MV) in Kanpur, India. Health to school children from reduced particle levels inside classrooms simulated to the lowest acceptable levels (ISHRAE Class C: PM10 ≤ 100 µg/m3 & PM2.5 ≤ 25 µg/m3) using air filters were examined. Lung deposition of particles was used as a proxy for health impacts and calculated using the MPPD model. The particle levels in all classrooms were above the baseline, with NV classrooms having higher particle masses than MV classrooms: 72.16% for PM1, 74.66% for PM2.5, and 85.17% for PM10. Our calculation reveals a whooping reduction in particles deposited in the lungs (1512% for PM10 and 1485% for PM2.5) in the case of the NV classrooms. Results highlight unhealthy air inside classrooms and suggest urgent interventions, such as simple filtration techniques, to achieve acceptable levels of particles inside schools. [ABSTRACT FROM AUTHOR]

Background and Objectives: “Adai” is a traditional South Indian breakfast prepared using the wet ground batter of white rice and pulses. Convenience foods are gaining popularity and owing to the increasing prevalence of noncommunicable diseases such as diabetes, there is a need for food products with lower glycemic index (GI). The current study aimed to develop an instant adai mix using brown rice, millets, pulses, and spices. Materials and Methods: The instant adai mix was prepared by blending pulverized brown rice, sorghum, and pulses (green gram, horse gram, decorticated and split red gram, black gram, and chickpea) along with roasted cumin, red chilies, and salt. The nutritional composition of the instant adai mix was analyzed, and GI of “adai” was evaluated in healthy human volunteers using International organization for standardization protocol. Results: The instant adai mix was rich in whole grains (48%) and pulses (45%). Nutritional profiling of the instant adai mix revealed that it is rich in protein and dietary fiber. One hundred grams of instant adai mix fulfill 27.8% of protein and 29.6% of dietary fiber requirements of recommended dietary allowance of adult male. Likewise, 100g of instant adai mix fulfill 34.9% of protein requirements of the estimated average requirement of an adult male. The “adai” prepared from the instant mix exhibited medium GI (65.1). Conclusion: The instant “adai” mix was found to be nutritionally superior, and the adai prepared from the mix showed a medium GI. It can be a healthy option compared with instant mixes containing refined grains such as white rice. More formulation trials are needed to prepare an adai mix to achieve a low GI. Reformulation of traditional foods with nutritious ingredients and achieving a lower GI can expand the healthier food choices for this vulnerable population who are at risk for type 2 diabetes. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to optimize meat slices for processing attributes to produce better sensory features in developed products from buffalo veal and chevon. The processing parameters such as meat particle size, fat content and binding ability without chopping were the subject of this study. Design/methodology/approach: The study involved three experiments where the particle size, fat content and tumbling time were optimized for optimum binding and improvement in different sensory attributes of product followed by physico-chemical analysis. Findings: The sensory scores clearly indicated that meat slices prepared from 3 mm meat particle size, 10% fat content and 1 h tumbling time were having best sensory features. The selected product was analyzed for different physico-chemical properties. Emulsion stability and cooking yield revealed significantly (p = 0.01) higher values of 91.6% and 89.7%, respectively, in buffalo veal than in values of 87.6% and 84.9%, respectively, in the chevon product. Similarly the results showed that buffalo veal slices had significantly (p = 0.01) higher (17.4%) protein than the chevon (15.2%), whereas chevon slices had significantly (p = 0.01) higher (10.3%) fat content. The texture profile analysis indicated that cohesiveness (p = 0.01) and chewiness (p = 0.05) were significantly higher in chevon product than in buffalo veal. Originality/value: The study was conducted to explore the buffalo veal as a potential source of quality meat, as majority of buffalo meat produced in India from spent animals have compromised quality attributes. The comparison was done with chevon, the most popular red meat in the country for the comparative study. [ABSTRACT FROM AUTHOR]

In this paper, the improved artificial bee colony (IABC) and improved particle swarm optimisation (IPSO) have been used for the optimal design of stepped spillway with the minimisation of construction cost as the energy dissipater structure for a dam project. Generally, the construction cost of this structure is the most expensive part of the project. However, traditional designing methods of stepped spillway such as the Vittal and Porey (VP) approach cannot find optimal dimensions of the stepped spillway with minimum cost. Therefore, the optimisation methods such as meta‐heuristic algorithms have been used. As a case study, Tehri dam's stepped spillway in India has been considered here and the optimal dimensions of this spillway have been obtained using IPSO, IABC algorithms and the results have been compared with VP approach and other available results. Comparison of the results shows that when the three‐stepped spillway is considered, the results of IABC and IPSO algorithms are improved by 17.72% in comparison with VP results. In addition, when the four‐stepped spillway is considered, the results of IABC, IPSO algorithms are, respectively, improved by 16.47% and 16.53% in comparison with the VP results. [ABSTRACT FROM AUTHOR]

This study reports on new particle formation (NPF) and characteristic features observed from a rural site falling in the rainshadow of the Western Ghats in peninsular India. A total of 35 NPF events observed during August 2018 - January 2019 are classified and analyzed here. The apparent formation rates ranged from 0.2 to 10.0 cm–3 s–1, while the growth rates of nucleation mode particles ranged from 1.2 to 13.8 nm h–1. The frequency of occurrence was least during August (core monsoon) and highest during post-monsoon. The local winds were calm and southeasterly to easterly (from the urban centre) supplying the essential precursor gases during October and November, leading to a frequent occurrence of nucleation events. Observations suggest that an increased condensation sink could limit the NPF while promoting Aitken mode growth. The newly formed particles accounted for about 10–80% of the total aerosol concentration. These newly formed particles were able to act as cloud condensation nuclei after growing to approximately 50 nm with an average activation fraction of 0.4. [ABSTRACT FROM AUTHOR]

The self potential data interpretation is very important to delineate and trace the mineralized zones in several regions. We study how to interpret self potential anomalies due to a finite two-dimensional inclined dike using the particle swarm algorithm. However, the precise estimation of the model parameters during the inverse solution are unknown. Here, we show that the particle swarm algorithm is capable of estimating the unknown parameters with acceptable accuracy. The evaluated parameters are the polarization parameter, the depth, the inclination angle, the width, and the location of the source of the target. We found in controlled in free-noise synthetic case that the particle swarm algorithm has a remarkable capability of assessing the parameters. For a noisy case, the results also are very competitive. Furthermore, it is utilized for real mineralized zones examples from Germany and India. Our results demonstrate how the particle swarm algorithm overcomes in trapping in local minimum solutions (undesired) and go faster to the global solutions (desired). Finally, the target parameters estimated are matched with accessible geologic and geophysical information. [ABSTRACT FROM AUTHOR]

Variable Energy Cyclotron Centre, a research organization under the department of Atomic Energy, Government of India, is a premiere accelerator center located in Kolkata (Fig. 1), India. This article describes the evolution this Centre since its inception to the present state of three different cyclotrons all operating successfully with three distinct purposes. The most interesting one is the oldest Variable Energy Cyclotron running successfully since June 16, 1977. It also describes other related facilities for continuing the associated research programme and briefs about various ongoing accelerator programmes. [ABSTRACT FROM AUTHOR]

Objective: Treatment of contaminated wounds represents a significant challenge in healthcare and there is a need to develop approaches maximising skin retention to maintain therapeutic concentrations of anti-infectives at the wound site. The objective of the present study was to develop and evaluate mupirocin calcium nanolipid emulgels to enhance wound healing performance and patient acceptability. Methods: Nanostructured lipid carriers (NLCs) of mupirocin calcium were prepared by the phase inversion temperature method using Precirol ATO 5 (Gattefosse, India) and oleic acid as lipids and Kolliphor RH 40 (BASF, India) as surfactant and further incorporated into a gel base for topical delivery. Results: The particle size, polydispersity index and zeta potential of mupirocin NLCs were found to be 128.8±1.25nm, 0.283±0.003 and –24.2±0.56mV, respectively. In vitro release studies from developed emulgel showed sustained drug release over 24 hours. Ex vivo drug permeation studies through excised rat abdominal skin showed better skin permeation (1712.38±15. 57μg/cm2) from developed emulgel compared to marketed ointment (827.92±21.42μg/cm2) after 8 hours, which was in agreement with in vitro antibacterial activity. Studies on Wistar rats indicated the nonirritant potential of developed emulgels. Further, mupirocin emulgels showed improved efficacy in percent wound contraction of acute contaminated open wounds in Wistar rats using a full-thickness excision wound healing model. Conclusion: The emulgels of mupirocin calcium NLCs appear to be effective in the treatment of contaminated wounds due to increased skin deposition and sustained release, thereby enhancing the wound healing potential of existing molecules. [ABSTRACT FROM AUTHOR]

Context: In India, teeth cleaning with tooth powder is common in rural and semi-urban areas. These dentifrices may contain low-quality abrasives, which may have a deleterious effect on dental hard tissues.Aims: This study aims to evaluate the tooth substance loss caused by different dentifrices and to correlate it with chemical composition, size, and shape of abrasives used.Settings and Design: An indigenously made automated machine was used for brushing the specimens.Materials and Methods: Sixty-four freshly extracted premolars were allocated to eight groups (n = 8). Colgate toothpaste was used as the control group. Each specimen was brushed in a vertical motion for 2½ h at 200 strokes/min with a constant applied load of 200 g corresponding to 6-month brushing. The difference in weight (pre- and post-brushing) was determined by an analytical weighing machine. Chemical analysis was done to determine the presence of iron oxide by Inductively Coupled Plasma Mass Spectrometry method. Shape and size of the abrasive particles was evaluated under scanning electron microscopy (SEM).Statistical Analysis Used: One-way analysis of variance and Paired t-test were used to analyze the data.Results: Tooth substance loss was maximum in the group brushed with red tooth powder, which was shown to contain the highest amount of iron oxide and also exhibited large, irregularly shaped abrasive particles under SEM.Conclusions: Tooth substance loss was documented to be correlated with chemical composition (iron oxide) and the size and shape of abrasive particles used in dentifrices. [ABSTRACT FROM AUTHOR]

The determination of particulate matter (PM 2.5 and PM 10 ) is very important due to its impact on climate, visibility reduction and natural environment. In order to identify their nature and relationship with the major synoptic-scale circulation patterns, particles were collected from Pune atmosphere and were analyzed in terms of morphology, carbonaceous species (organic and elemental carbon) and elemental concentration. Average mass concentrations of PM 2.5 and PM 10 were 104.57 ± 25.70 μg m − 3 and 169.91 ± 60.75 μg m − 3 , respectively for the entire study period. This indicates that observed values of PM are substantially higher than NAAQS and WHO standards, respectively. The ratio between PM 2.5 and PM 10 was calculated and varied from 0.51 to 0.78 indicating abundance of fine particles over Pune during the study period. Carbonaceous analysis results showed that concentrations of OC and EC were 31.25 and 2.73 μg m − 3 for PM 2.5 while 33.14 and 2.40 μg m − 3 for PM 10 , respectively. The calculated OC/EC ratios were 15.83 and 17.24 for PM 2.5 and PM 10 , respectively indicating abundance of organic carbon which suggests the excess of secondary organic aerosols. The morphological traits such as circularity (< 1) and aspect ratio (> 1) were determined which indicate that the particles are not perfectly spherical and not elongated in any direction in both size ranges. Effective carbon ratio (ECR) an approach for climate was found to have an average value of 2.42 and 1.74 for PM 2.5 and PM 10 . This clearly indicates that abundance of SOC and lower values of POC and EC could lead to the reduction in atmospheric warming effect due to combustion PM and increases scattering properties of incoming radiations. The monthly air mass backward trajectory cluster analysis was performed which supports the transport of aerosols from the long range transportation as well as the dominance of local sources over SW Indian region. The contribution of local sources was further determined which indicates that motor vehicle is the dominant emitter of carbonaceous aerosols in Pune. [ABSTRACT FROM AUTHOR]

Abstract: Influence of aerosol composition on visibility degradation in megacity Delhi has been quantified using model-derived seasonal mean aerosol composition constrained by satellite-measured columnar aerosol optical depth spectrum. Aerosols contribute ∼90% to the observed visibility degradation in non-foggy condition, while its relative contribution decreases rapidly at RH ≥ 80% due to stronger relative influence of fog droplets on attenuation of radiation, especially during the winter season. Visibility is most sensitive to water-soluble particles and soot in all seasons. Sensitivity study shows that visibility does not respond strongly to reduction of mass concentration of insoluble, accumulation mode and coarse mode dust particles. Reduction of mass concentration of soot and water-soluble particles in the range of 10%–50% will lead to an increase in visibility by 2.4 ± 0.1%–11.3 ± 1.6% and 4.9 ± 2%–29 ± 12% respectively. Reduction of the last two anthropogenic components has co-benefits, as it may reduce fog formation and thus further enhance the visibility along with an improved air quality in terms of associated health and climatic effects. [Copyright &y& Elsevier]

Abstract: A 2D Hydrodynamic–Particle Analysis model was applied to the Gulf of Kachchh (GoK) to estimate the residence time of pollutants. The tidal currents in the Gulf have a strong E–W component, which prevents the material in the north being transported towards south. In the regions situated very close to the open boundary, where the GoK waters exchange freely with the northern Arabian Sea, dilution takes place rapidly with the incoming waters and hence, the residence time is on the order of 1day. Influence of eddies and a dynamic barrier across the Sikka–Mundra section on the residence time is apparent. Eastern GoK shows a relatively large residence time, on the order of 2–4days, warranting caution while releasing industrial wastes in the northeastern Gulf. The region around location-5 behaves like a bay; the dissolved matter gets trapped in this bay and the residence time increases by 3–4days. [Copyright &y& Elsevier]

Abstract: Daily variability in the chemical composition of atmospheric PM2.5 and PM10 has been studied from an urban site (Ahmedabad) in western India over a span of 30days during winter. The PM2.5 and PM10 mass concentrations ranged from 32 to 106μgm−3 and 121 to 327μgm−3, respectively. On average, PM2.5 constitutes ~33% of PM10, indicating dominance of coarse mode aerosols in the urban atmosphere. The particulate EC and OC show higher abundances in PM2.5 (average: 3.0±0.9 and 18.3±5.9μgm−3 respectively) whereas those in PM10 are 4.4±2.4 and 29.8±11.2μgm−3 respectively. A linear increasing trend and representative OC/EC ratio of 6.2 indicate their primary source from biomass burning emissions. The water-soluble organic carbon (WSOC: 4.0–14.7μgm−3) and its linear relationship with K+ (0.6–1.7μgm−3) in PM2.5 further support biomass burning emissions as a dominant source for carbonaceous aerosol. Among water-soluble inorganic species, SO4 2− is the most abundant (range: 3.2–22.5μgm−3); almost all of it occurs in fine mode (PM2.5) and exhibits near-quantitative neutralization with NH4 + (r=0.98, slope: 1.3). The water-soluble Ca2+ and Mg2+ mainly abundant in the coarse mode, suggest significant contribution from mineral dust. Documenting large temporal variability in the chemical composition of coarse and fine mode aerosol is essential in order to assess the changing regional emission scenario over mega-cities and their down-wind transport. [Copyright &y& Elsevier]

The article presents a case study on occupational hazards and industrial safety of the workers in the cricket bat manufacturing industry in Kashmir, India. In the process workers were selected based on a random sampling technique. With the help of a sound level meter, noise level, temperature and dust concentration were measured. It concludes by stating the need for immediate government intervention for providing a safer and healthier occupational environment for quality outcomes.

Abstract: Mine fires due to spontaneous combustion in coal mines is a global concern. This leads to serious environmental and safety hazards and considerable economic losses. Therefore it is essential to assess and classify the coal seams with respect to their proneness to spontaneous combustion to plan the production, storage and transportation capabilities in mines. This paper presents the formulation of clustering problem into a linear assignment model and the application of a discrete particle swarm optimization approach for the classification of coal seams based on their proneness to spontaneous combustion. In this research work, twenty nine coal samples of varying ranks belonging to both high and low susceptibilities to spontaneous combustion have been collected from all the major coalfields of India. Using moisture, volatile matter, and ash content and crossing point temperature of the coal samples as the parameters, the proposed algorithm has been applied to classify the coal seams into three different categories. This classification will be useful for the planners and field engineers for taking ameliorative measures in advance for preventing the occurrence of mine fires. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the concentration of acid and water-soluble ions (Na+, K+, Mg++, Ca++, F−, Cl−, NO3 − and SO4 − −) in different particle size range (>1.1–<2.0μm, >2.0–<3.3μm, >3.3–<4.7μm, >4.7–<5.8μm, >5.8–<9.0μm and >9μm–<10μm) of PM10 atmospheric aerosols collected by six stages Anderson Cascade Impactor were determined using conductivity suppressed ion-chromatography system. Suspended particulate matters in the form of respirable (PM10) aerosols were collected on the roof of a three storied building at a height of 20m above the ground, at Bhabha Atomic Research Centre (BARC), Mumbai using Hi-Volume Sampler (HVS) with Whatman glass fiber filter paper during the period of March–June 2009. The sequence of solubility of ions in both extractants (acid+water) of PM10 aerosols from greatest to least was found to be Na+ >Ca++ >K+ >Cl− >F− >Mg++ >NO3 − ≈SO4 −−. The average concentration of Na+, K+, Mg++, Ca++, F−, Cl−, NO3 − and SO4 −− in PM10 aerosols was estimated to be 13.36g/kg, 3.76g/kg,0.251g/kg,3.771g/kg,0.833g/kg,1.17g/kg, 81μg/kg and 290μg/kg respectively. The enrichment of particular ion in soluble components may be due to its high abundance in PM10 aerosols, less sorptivity with the tiny solid particles of atmospheric dust, high extractability and leachability, high solubility and mobility. By classifying the PM10 aerosols into two categories viz fine particle (<2.5μm) and coarse particle (>2.5μm–<10μm), it was found that generally, in the fine particle, the geometric mean concentration of total soluble ions in acid and water components was found to be higher than coarse particle. Overall, it was also observed that generally as particle size increases, the geometric mean concentration of soluble ions in both extractants of PM10 aerosols decreases. [Copyright &y& Elsevier]

For the first time, simultaneous study on physical and chemical characteristics of PM, PM, and rainwater chemistry was attempted over the Bay of Bengal in monsoon season of 2009. The aerosols and rainwater samples were collected onboard ship 'SK-261, ORV Sagar Kanya' during Oceanographic Observations in the Northern Bay of Bengal under the Continental Tropical Convergence Zone (CTCZ) program conducted during 16 July to 19 Aug 2009. Aerosol samples collected by PM and PM were analyzed for various water soluble (Na, K, Ca, Mg, NH, Cl, SO and NO and acid soluble (Fe, Al, Zn, Mn and Ni) ionic constituents. The pH of rainwater varied from 5.10 to 7.04. Chloride ions contributed most to the total ion concentration in aerosol and rainwater, followed by Na. Significant contributions of SO, NO and NH found in PM, PM and high concentrations of TSP and non sea-salt SO over the mid-ocean is attributed to the long range transport of anthropogenic pollution from the Indian continent. The scavenging ratio was maximum for coarse particles such as Ca and minimum for fine particles like NH [ABSTRACT FROM AUTHOR]

Abstract: This work focuses on size segregated atmospheric aerosol mass concentrations and water soluble inorganic components in Chhattisgarh, the eastern central India. Investigation on the monitoring of ambient air levels of atmospheric particulates were done around a large source of primary anthropogenic particulate emissions: the industrial area and coal based power plants. Chemical characterization was carried out for aerosol samples collected in urban area, Raipur, (21°14′N, 81°38′E) of Chhattisgarh region over a period of one year, using cascade impactor. Annual mean of mass concentration for coarse (PM2.5–10) and fine (PM2.5) aerosols were monitored to be 238.1±89.9 and 167.0±75.3µgm−3 respectively This work deals with the seasonal variation and meteorological influences of inorganic components of the aerosols viz. NO3 −, Cl− and SO4 2−, Mg2+, Na+, K+, Ca2+ and NH4 +. The annual mean concentration of the inorganic components were monitored to be 3.8±2.5, 8.9±2.7, 10.2±1.5, 2.6±0.6, 8.7±7.2, 4.6±1.8, 16.4±6.9 and 0.4±0.5µgm−3 respectively in coarse particles and 8.2±7.1, 6.8±3.6, 46.5±32.8, 1.7±0.6, 7.4±3.6, 5.9±3.4, 10.2±2.9, and 8.8±7.7µgm−3 respectively in fine particles, for the above ions. The average distribution of nitrate and sulphate in PM2.5–10 were found to be 1.6 and 4.2% and in PM2.5 were 4.9 and 27.9% respectively indicating the dominance of sulphate in both PM2.5–10 and PM2.5 particles. Here, industrial emission plays important role for contribution of PM2.5 particle loading in the atmosphere. The cation–anion rational analysis indicated that the PM2.5–10 particles were mostly neutralized and PM2.5 particle were acidic. The major ions were mainly in the form of NaCl>CaSO4 >K2SO4 >MgSO4 >KCl>NH4Cl>Ca(NO3)2 >KNO3 >MgCl2 >Mg(NO3)2 >NH4NO3 >(NH4)2SO4 in coarse aerosol particles and (NH4)2SO4 >K2SO4 >CaSO4 >NaCl>NH4NO3 >CaCl2 >KNO3 >MgCl2 >Ca(NO3)2 >KCl>NH4Cl in fine particles. [Copyright &y& Elsevier]

flue gas conditioning (DFGC) deals with the addition of chemical additives such as ammonia and sulfur trioxide, simultaneously, to the flue gas for increasing the ash collection efficiency of electrostatic precipitators (ESPs). Previous studies with ammonia as the conditioning agent [i.e., ammonia flue gas conditioning (AFGC)] have revealed that the collection efficiency increases drastically due to agglomeration of ash particles. However, in what way combination of sulfur trioxide and ammonia helps in increasing the efficiency of ESPs, and hence controlling emissions from the power stations, has not yet been studied in detail. With this in view, efforts were made to investigate the influence of DFGC and AFGC on the collection efficiency of ESPs and overall properties of the ash. To achieve this, fly ash samples from a thermal power station in India, where DFGC is being adopted, were collected and their physico-chemico-mineralogical and morphological properties were investigated. The results obtained were critically analyzed vis-a-vis those obtained for the fly ash samples collected from a thermal power plant where only AFGC is being adopted. The advantage of DFGC over AFGC for enhancing the overall collection efficiency of ESPs has been demonstrated in this paper. [ABSTRACT FROM AUTHOR]

Recent research has suggested that the adverse health effects caused by nanoparticles are associated with their surface area (SA) concentrations. In this study, SA was estimated in two ways using number and mass concentrations and compared with SA (SAmeas) measured using a diffusion charger (DC). Aerosol measurements were made twice: once starting in October 2002 and again starting in December 2002 in Mysore, India in residences that used kerosene or liquefied petroleum gas (LPG) for cooking. Mass, number, and SA concentrations and size distributions by number were measured in each residence. The first estimation method (SAPSD) used the size distribution by number to estimate SA. The second method (SAINV) used a simple inversion scheme that incorporated number and mass concentrations while assuming a lognormal size distribution with a known geometrical standard deviation. SAPSD was, on average, 2.4 times greater (range=1.6–3.4) than SAmeas while SAINV was, on average, 6.0 times greater (range=4.6–7.7) than SAmeas. The logarithms of SAPSD and SAINV were found to be statistically significant predictors of the logarithm of SAmeas. The study showed that particle number and mass concentration measurements can be used to estimate SA with a correction factor that ranges between 2 and 6. [Copyright &y& Elsevier]

Abstract: Size-fractionated bacterial production, abundance and α- and β- glucosidase enzyme activities were studied with respect to changes in hydrography, total suspended matter (TSM), chlorophyll a, particulate organic carbon and nitrogen ratio (POC:PON), 1.5M NaCl-soluble and 10mM EDTA-soluble carbohydrates (Sal-PCHO and CPCHO) and transparent exopolymeric particles (TEP) in the surface waters from July 1999–2000 at a shallow coastal station in Dona Paula Bay, west coast of India. The bulk of the total bacterial production and glucosidase activity were associated with particles (75% and >80%, respectively). Total bacterial production was linearly correlated to chlorophyll a (r =0.513; p <0.05) whereas enzyme activity was significantly correlated to TSM (α-glucosidase: r =0.721 (p <0.001); β-glucosidase: r =0.596 (p <0.01)). Both α-glucosidase (r =0.514; p <0.05) and β-glucosidase enzymes (r =0.598; p <0.01) appeared to be involved in the degradation of CPCHO and Sal-PCHO, respectively. Changes in α-glucosidase/β-glucosidase ratios highlighted the varying composition of particulate organic matter. The bacterial uptake of 14C-labeled bacterial extracellular carbohydrate measured over 11days showed a strong linear correlation between 14C-uptake and bacterial production using tritiated thymidine. The turnover rate of 14C-labeled carbohydrate-C was 0.52d−1, higher than the estimated annual mean potential carbohydrate carbon turnover rate of 0.33±0.2d−1. Our study suggests that carbohydrates derived from sediments may serve as an important alternative carbon source sustaining the bacterial carbon demand in the surface waters of Dona Paula Bay. [Copyright &y& Elsevier]

As received cenospheres obtained from Rihand Super Thermal Power Plant, Uttar Pradesh,India, were processed using sink float method. The solvent system consisted of 1% TEALS (Triethanolamine lauryl sulphate) in acetone. Further flotation of the float with the same solvent system led to another float. Various fractions thus obtained were characterized in respect of their chemical, mineralogical, and morphological properties. The float obtained from second flotation was richer in cenospheres, which are round and within a small size range. The residues obtained were broken spheres. Phase-mineralogical analysis has revealed mullite enrichment in the floats. Chemical composition of the various fractions does not indicate high concentration of harmful elements. SEM analysis leads to the conclusion that the cenospheres are essentially open-pore type. Based on such experimental observations, various potential uses have been suggested. [ABSTRACT FROM AUTHOR]

The article reports on the study of the variation of fine particles and the influence of temperature and relative humidity in the residential areas of Lucknow city in India namely Vikas Nagar and Alambagh. The study shows that the concentration level of fine particles in Alambagh is 13.74 percent higher than the Vikas Nagar level. It also states that vehicular pollution is one of the important sources of fine particles. The study also mentions that the concentration level of fine particles in Lucknow city will be best predicted through its relative humidity.

Abstract: According to the Earth Observatory dust outbreaks are considered as natural hazards, which affect the ecosystems and human life. The main objective of this study is to assess and monitor the movement of aerosols and pollutants from local or other sources, both natural and anthropogenic, using a combination of ground-based monitoring and satellite data. The turbid and polluted atmosphere in the densely-populated area of Hyderabad, India is further degraded from dust outbreaks originated from Thar desert. A dust event occurred during 10th to 11th April 2006 in the northwest region of India; its plume substantially spread across the downwind direction affecting the study region. Using both irradiance measurements and satellite data this dust event is investigated. The analysis shows a significant change in Aerosol Optical Depth (AOD), Aerosol Index (AI) and aerosol-particle size during the dust event. The Aerosol Optical Depth in the dusty day is about 0.2 higher than the previous non-dusty days, while the Ångström exponent rapidly decreases when the dust plume affected the study area. The surface PM concentrations show enhanced values during the dusty day directly influenced by the dust deposition. There is also a remarkable decrease in ground-reaching global radiation, UV erythemal (UVery) and other irradiance components. The analysis suggested that the use of the diffuse-to-direct-beam ratio is the most appropriate parameter for the dust monitoring since its values at the longer wavelengths are not affected by the solar zenith angle. [Copyright &y& Elsevier]

Daily average PM10 (particulate matter which passes through a size selective impactor inlet with a 50% efficiency cut-off at 10μm aerodynamic diameter), TSP (total suspended particulate matter) and their chemical species mass concentrations were measured at residential and industrial sites of an urban region of Kolkata during November 2003–November 2004. Source apportionment using chemical mass balance model revealed that the most dominant source throughout the study period at residential site was coal combustion (42%), while vehicular emission (47%) dominates at industrial site to PM10. Paved road, field burning and wood combustion contributed 21%, 7% and 1% at residential site, while coal combustion, metal industry and soil dust contributed 34%, 1% and 1% at industrial site, respectively, to PM10 during the study period. The contributors to TSP included coal combustion (37%), soil dust (19%), road dust (17%) and diesel combustion (15%) at residential site, while soil dust (36%), coal combustion (17%), solid waste (17%), road dust (16%) and tyre wear (7%) at industrial site. Significant seasonal variations of the particulate matters have been observed during the study period. In the monitoring sites total carbon, organic carbon and iron were found to be the marker species of road dust, while organic carbon, total carbon, chloride and sulfate have been observed as the marker species of soil dust in TSP. [Copyright &y& Elsevier]

Abstract: Results from a variety of complementary aerosol measurements made as part of the Indian Space Research Organization-Geosphere Biosphere Program (ISRO-GBP) road campaign experiment conducted during Feb 2004 in the central Indian region are reported. An instrumented vehicle fitted with the Micro Pulse Lidar for aerosol vertical profile measurements, nephelometer for scattering and athelometer for absorption coefficients measurements, Microtops II sun-photometer for column aerosol optical depth, Quartz Crystal Microbalance for aerosol mass concentration and Grimm spectrometer for aerosol number concentration was used in the campaign. The synergy of results from these complementary measurements is reflected in the computed aerosol radiative forcing for the region. We show that the large spatial and temporal variations found in the aerosol characteristics over the northwest Indian region are caused mainly by the naturally produced dust particles. The variation in their concentration modulates the overall atmospheric radiative forcing over this region. We also show that apart from the large north to south gradient in aerosol forcing caused due to transport of aerosols from the continent to the Indian Ocean region and reported during INDOEX, there is also a positive gradient in aerosol forcing from west to east, from the Arabian Sea to the Bay of Bengal region. A considerable portion of particles produced from the Indian main land is flushed to the Bay of Bengal region before being transported to the Indian Ocean, causing this west to east gradient. [Copyright &y& Elsevier]

Ambient concentrations of PM2.5 and PM10 are of concern with respect to effects on human health and environment. Increased levels of mortality and morbidity have been associated with respirable particulate air pollution. In India, it is not yet mandatory to monitor PM2.5 levels therefore very limited information is available on PM2.5 levels. To understand the fine particle pollution and also correlate with PM10 which are monitored regularly in compliance with ambient air quality standards. This study was carried out to monitor PM2.5, PM10, and NO2 for about one year in a residential cum commercial area of Mumbai city with a view to understand their correlation. The average PM2.5 concentration at ambient and Kerbsite was 43 and 69 μg/m3. The correlation coefficients between PM2.5 and PM10 at ambient and Kerbsite were 0.83 and 0.85 respectively thus indicating that most of the PM2.5 and PM10 are from similar sources. TSP, PM10 levels exceeded Central Pollution Control Board(CPCB) standard during winter season. PM2.5 levels also exceeded 24 hourly average USEPA standard during winter season indicating unhealthy air quality. [ABSTRACT FROM AUTHOR]

In developing countries, aerosol particles damage the health of hundreds of millions of people. Migration from the country side to megacities increases emissions and exposure to particles. Some countries have started to limit emissions based on particulate mass, but this may increase particle number concentrations. In this study we discuss some earlier measurements carried out in the developing world and compare results from one-week measurement campaigns concerning the particle number size distribution and PM10 mass concentrations in New Delhi, India and Beijing, China. Our results show that submicron particle concentrations are high in both places. The average PM10 concentration was 360 μg/m3 in New Delhi and 120 μg/m3 in Beijing. The corresponding total particle number concentrations in the size range 3–800 nm were 63 000 cm−3 and 35 000 cm−3. Number and mass concentrations and their characteristics showed significantly different behaviour between these two locations, which stresses the importance of long-term simultaneous measurements of both quantities in different types of megacities. [ABSTRACT FROM AUTHOR]

This paper presents dry deposition of major ions on tropical foliage (leaves of Ashok (Polyalthia longifolia) and Cassia (Cassia siamea)) at St John's, Agra, an urban site of tropical India on nonrainy, nondewy, and nonfoggy days. The deposition flux was higher on Cassia leaf than Ashok leaf probably due to a rougher surface as shown by scanning electron microscopy. Dry deposition of cations varies from 0.46 to 12.16 mg m-2 day-1 while anions vary from 0.04 to 3.24 mg m-2 day-1. The percentage contribution of alkaline components is greater than that of acidic components, indicating the alkaline nature of dry deposition. Two-way analysis of variance results reveal significant seasonal variation only for K+ SO42-, and F-; however, values varied season to season for Na+, Ca2+, Mg2+, Cl-, NO3-, and NH4+ also. The large seasonal variation in deposition flux may be due to meteorological conditions, diameter of particles, and variation in atmospheric level. SO42- and NO3- show significant correlation, indicating their origin from similar sources while significant correlation between Ca2+ and Mg2+ implies their origin from soil. Poor correlation between Ca2+ and SO42-, Ca2+ and NO3-, and Mg2+ and SO42- indicates that in addition to soil other sources also contribute to dry deposition. Low dry deposition fluxes of SO42- and NO3- compared to Ca2+ and Mg2+ may be due to low mass medium diameters of SO42- and NO3- and may be due to uptake through the stomatal pores abundant on leaf surfaces. Factor analysis was employed to identify the sources. F-, Cl-, SO42-, NO3-, and K+ are grouped together in the first factor, indicating their probable contribution from combustion, Ca2+, Mg2+, and NH4+ are grouped in factor II, which may be attributed to road dust and soil, and factor Ill includes mainly Na+ and F-, probably contributed from brick-kiln industries. Atmospheric concentrations of F-, Cl-, NO3-, SO42-, Na+, K+, Ca2+, Mg2+, and NH4+ were found to be 0.38, 2.28, 1.31, 2.74, 0.44, 0.59, 1.21, 1.2, and 2.29 μg m-3, respectively. [ABSTRACT FROM AUTHOR]

Particulate mass size distributions were measured during cooking and non-cooking periods in three Indian urban household kitchens with Liquefied Petroleum Gas as fuel. Based on the measured mass size distributions, fraction of particulate deposition in the respiratory system were calculated for a healthy Indian female using a deterministic lung deposition model. Respiratory physiological data of Indian women were collected from the published data. These physiological parameters were incorporated in the model to determine the particulate deposition in the respiratory system. The cooking generated very high concentration of particles 4 to 5 times more than the non-cooking background periods. Particulate size distributions in both cooking and non-cooking periods showed bimodal characteristics. Cooking process generated particles predominantly in accumulation mode (0.1–0.3 μ m) whereas during non-cooking periods particulates are found in coarse mode (1.0–2.0 μ m). Also, during frying process, the particulates were found to have a predominant coarser/droplet mode 0.7–1.0 μ m. The highest deposition was observed in pulmonary region during cooking periods. The study shows that the daily particulate dose to the urban Indian women from domestic cooking is comparable with the dose resulting from outdoor particulate exposure. [ABSTRACT FROM AUTHOR]

Coal combustion in the power sector gives rise to the emission of primary and secondary particulate pollutants. Since the emission of pollutants depends on coal quality and combustion technology, and given that transport, transformation and deposition of contaminants depend on regional climatic conditions, specific studies for the power stations is needed to evaluate their environmental impacts. Monitoring of ambient respirable suspended particulate matter (RSPM) and suspended particulate matter (SPM) levels around a large coal-fired power station in India was carried out. The specific objectives were the determination of spatial and seasonal variability in RSPM and SPM levels, and their relationship with meteorological parameters such as wind velocity and relative humidity. The results have shown a marked seasonal trend and spatial variability in RSPM and SPM levels in the study area. Higher concentrations of ambient RSPM and SPM were found in downwind monitoring stations compared to upwind direction. Ratios of RSPM to SPM and correlation coefficient values between RSPM and SPM along with meteorological parameters were also worked out. Relative humidity and wind velocity have shown an inverse relation with particulate deposition pattern. [ABSTRACT FROM AUTHOR]

This paper presents the measurements of gaseous SO2, NO2, HNO3 and NH3 and particulate NH4+, NO3−and SO42− at Rampur, a rural site of semi-arid region of India and annual mean concentrations are 3.7±2.2, 7.3±3.7, 0.7±0.6 and 6.7±4.2 and 1.0±0.4, 1.1±1.3 and 2.6±1.6 μg m−3, respectively. Seasonal variation with higher concentration in winter is observed for gaseous SO2, NO2, and NH3 and particulate NH4+. The concentration of HNO3 and particulate NO3−and SO42− are higher in summer. Summer to winter ratio of HNO3 and particulate NO3− are 3.8 and 1.8, respectively, showing seasonal variation is more pronounced in case of HNO3 than particulate NO3−. The ratio of gaseous NH3 to particulate NH4+ (NH3/NH4+) is more than 1 probably due to basic nature of aerosol. Examination of equilibrium between gaseous NH3 and HNO3 and particulate NH4NO3 shows observed equilibrium constant is lower than theoretical equilibrium constant in summer and vice versa in winter. [Copyright &y& Elsevier]

Since the past two decades, high aerosol loading is being observed over the Indian mainland. It becomes necessary to continuously monitor and understand the distribution of aerosol loading over the Indian landmass, as it might have serious health and climatic implications. Whereas there have been extensive studies reporting seasonal distribution and trends of columnar aerosol amounts over the Indian region using data from ground based as well as space borne measurements, in-depth studies on the aerosol vertical profile distribution and in particular, seasonal trends are still lacking. This paper demonstrates the seasonal variability of aerosol vertical structure over the Indian mainland using decadal daily datasets (2009–2018) from CALIOP Lidar (onboard NASA-CNES's CALIPSO satellite) augmented by the variability in columnar AOD from MODIS (onboard NASA's AQUA and TERRA platforms). The changing aerosol amounts in both vertical and total column levels have also been presented. Over Indian landmass, we could find statistically significant increasing trends in aerosol extinction within lower altitude levels during all the seasons. The trends in the vertical distribution of aerosols are also compared with respect to trends in AOD derived from MODIS (Aqua/Terra). Additionally, we have also examined the seasonal variability and trends of aerosol extinction over five selected cities (based on pollution and population levels) of the country. • Decadal-scale seasonal variability of aerosol extinction profiles over India. • Increasing vertical and columnar trends of aerosols during all seasons. • Small and spherical particles more dominant during October–February. [ABSTRACT FROM AUTHOR]

The article presents information on the study on the particulate removal in a novel spray-cum-bubble column scrubber conducted by Raj Mohan and Meikap. The study found out that the particulate matters concentration in and around Indian metallurgical and chemical metallurgical process plants sometimes overshoots the danger point. It states that it is important to remove the pollutants by a low-energy dissipation scrubber.

Estuaries with poor flushing and longer residence time retain effluents and pollutants, ultimately resulting in eutrophication, a decline in biodiversity and, finally, deterioration of water quality. Cochin Estuary (CE), southwest coast of India, is under the threat of nutrient enrichment by the anthropogenic interventions and terrestrial inputs through land runoff. The present study used the FVCOM hydrodynamic model coupled with the Lagrangian particle module (passive) to estimate the residence time and to delineate site-specific transport pathways in the CE. The back and forth movements and residence time of particles was elucidated by using metrics such as path length, net displacement and tortuosity. Spatio-temporal patterns of the particle distribution in the CE showed a similar trend during monsoon and post-monsoon with an average residence time of 25 and 30 days, respectively. During the low river discharge period (pre-monsoon), flood-ebb velocities resulted in a minimum net transport of the water and longer residence time of 90 days compared to that of the high discharge period (monsoon). During the pre-monsoon, particle released at the southern upstream (station 15) traversed a path length of 350 km in 90 days before being flushed out through the Fortkochi inlet, where the axial distance was only 35 km. This indicates that the retention capacity of pollutants within the system is very high and can adversely affect the water quality of the ecosystem. However, path length (120 km) and residence time (7.5 days) of CE were considerably reduced during the high discharge period. Thus the reduced path length and the lower residence time can effectively transport the pollutants reaching the system, which will ultimately restore the healthy ecosystem. This is a pioneer attempt to estimate the flushing characteristics and residence time of the CE by integrating the hydrodynamics and Lagrangian particle tracking module of FVCOM. This information is vital for the sustainable management of sensitive ecosystems. [ABSTRACT FROM AUTHOR]

Indoor air pollution associated with combustion of solid fuels seems to be a major contributor to the national burden of disease in India, but relatively few quantitative exposure assessment studies are available. This study quantified the daily average concentrations of respirable particulates (50% cut-off at 4μm) in 412 rural homes selected through stratified random sampling from three districts of Andhra Pradesh, India and recorded time activity data from 1400 individuals to reconstruct 24-h average exposures. The mean 24-h average concentrations ranged from 73 to 732μg/m3 in gas- versus solid fuel-using households, respectively. Concentrations were significantly correlated with fuel type, kitchen type, and fuel quantity. The mean 24-h average exposures ranged from 80 to 573μg/m3. Among solid fuel users, the mean 24-h average exposures were the highest for women cooks and were significantly different from men and children. Among women, exposures were the highest in the age group of 15–40 years (most likely to be involved in cooking or helping in cooking), while among men, exposures were highest in the age group of 65–80 years (most likely to be indoors). The data are being used to develop a model to predict quantitative categories of population exposure based on survey information on housing and fuel characteristics. This would facilitate the development of a regional exposure database and enable better estimation of health risks. [ABSTRACT FROM AUTHOR]