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Pawar G.V.,Nowrosjee Wadia College | Devara P.C.S.,Indian Institute of Tropical Meteorology | More S.D.,University of Pune | Pradeep Kumar P.,University of Pune | Aher G.R.,Nowrosjee Wadia College
Aerosol and Air Quality Research | Year: 2012

Simultaneous measurements of aerosol optical depth and incoming global solar flux were carried out with a MICROTOPS-II Sunphotometer and Eppley Precision Spectral Pyranometer over Nowrosjee Wadia College (NWC, Pune) as the nodal centre, and at Pune University (PU) and IUCAA Girwali Observatory (IGO), in a field campaign mode during December 2010-May 2011. Data was analyzed to determine the surface short-wave (SW) aerosol direct radiative forcing (ADRF, ΔF per unit 0.1 AOD) and to study the characteristics of the aerosols. The results indicate that ADRF shows significant day-to-day variability and co-varies with AOD. The cause of the day-to-day variation in ADRF is an anticorrelation between ADRF/AOD, and differences in the daily maximum minus minimum RH and temperature. At NWC, ADRF ranges between -37.7 W/m2 (highest) and -5.9 W/m2 (lowest). For 500 nm, ADRF takes values in the range -17.3 ± 7.1 W/m2 to -54.2 ± 5.5 W/m2 at PU, whereas the corresponding values at IGO are -15.1 ± 2.1 W/m2 and -36.6 ± 6.4 W/m2. Monthly ADRF is at the minimum level in winter and maximum during the pre-monsoon period. The magnitude of AOD shows significant diurnal variability. In winter, the mean AOD diurnal percentage departure at 500 nm is positive in the morning and negative during the afternoon, and this is reversed in the pre-monsoon period. The diurnal cycle of AOD is related to the prevalent meteorological conditions, surface-based nocturnal temperature inversion in the atmospheric boundary layer (ABL), and influx of aerosols from different source regions. © Taiwan Association for Aerosol Research.

More S.,University of Pune | Pradeep Kumar P.,University of Pune | Gupta P.,Universities Space Research Association | Devara P.C.S.,Indian Institute of Tropical Meteorology | Aher G.R.,Nowrosjee Wadia College
Aerosol and Air Quality Research | Year: 2013

Aerosol Optical Depth (AOD) measurements from Aerosol Robotic NETwork (AERONET; level 2.0), Microtops - II sun-photometer and MODerate Resolution Imaging Spectroradiometer (MODIS) (Terra and Aqua; level 2, collection 5, dark target) were compared and used to characterize aerosols over Pune, India. AODs from Microtops and MODIS were compared with those measured by AERONET to evaluate the measurement quality. To the best of our knowledge, this is the first systematic comparison of MODIS aerosol products over Pune, India. The results of the analysis show that during 2008-10, 68% to 84% of the MODIS AODs fell within an expected error, as defined by the MODIS science team, and thus the retrievals from this system are validated and accepted. In addition, during pre-monsoon periods MODIS retrievals are better-matched with ground-based measurements. On the seasonal scale, MODIS retrievals corroborate well with ground-based measurements, with correlation coefficients ranging from 0.62 to 0.93. Despite an overall satellite-ground agreement, MODIS tends to under-estimate AOD during winter, and this may be due to improper assumptions of surface reflectance and the incorrect selection of aerosol types. AERONET retrieved single scattering albedo (SSA) values in winter (0.82-0.86), suggesting the dominance of absorbing aerosols, slightly increased (0.87-0.89) in pre-monsoon season, indicating more scattering type of aerosols. These values are about 8.9%-1.1% lower than those of the assumed SSA values in the MODIS algorithm. © Taiwan Association for Aerosol Research.

Jamdade S.G.,Nowrosjee Wadia College | Jamdade P.G.,College of Engineering, Pune
International Journal of Renewable Energy Research | Year: 2012

Wind speed is the most important parameter in the design and study of wind energy conversion systems (WECS). The main aim of this study is to assess wind power potential of a site for wind power plant development. Availability of wind energy and its characteristics at Malin Head, Dublin Airport, Belmullet and Mullingar in Ireland has been studied based on primary data collected at these sites for a period of seven years. The wind speeds at height of 50 m above ground level were measured. Two parameter Weibull distribution's linear regression model is used for analyzing wind speed pattern variations. Weibull parameters are calculated by using Least Squares Fit Method (LSM). Our analysis shows that the coastal sites of Ireland such as Malin Head, Dublin Airport and Belmullet have good wind power potentials. These potentials if utilized they will provide solution towards power shortage problem of Ireland. Large magnitudes of winds for power generation occurred during the months of October to March and in May month.

Ranade N.V.,Nowrosjee Wadia College | Gharpure D.C.,University of Pune
ISPTS 2015 - 2nd International Symposium on Physics and Technology of Sensors: Dive Deep Into Sensors, Proceedings | Year: 2015

Electrical Impedance Tomography (EIT) has its applications in several areas like medical imaging, process tomography, geophysical mapping of earth's crust and non destructive testing. Every application of EIT demands specific requirements from the instrumentation which is used to gather surface potential data from the object to be inspected. Key issues regarding design and choice of instrumentation are discussed in this paper. A data acquisition system for EIT is designed, developed and tested for certain conductivity range and adjacent excitation adjacent measurement strategies. The preliminary results show agreement with the reported data. The simple and low cost hardware developed in this work is useful for acquiring complete data set required for image reconstruction in EIT. The discussion regarding key issues in designing EIT instrumentation will be useful while developing any new application of EIT. © 2015 IEEE.

Bashir W.,Nowrosjee Wadia College | Borkar V.T.,Nowrosjee Wadia College | Dangat V.T.,Nowrosjee Wadia College
Asian Journal of Chemistry | Year: 2016

The kinetics and mechanism of the rapid bromination of the nucleobase uracil, by molecular bromine in aqueous medium at pH 7 has been studied employing hydrodynamic voltammetry, NMR and FTIR. The formation of the mono-bromo derivative is found to be a second order rapid reaction. The rate constant, energy of activation and frequency factor for the reaction have been determined and a probable mechanism for the reaction has been proposed. © 2016, Chemical Publishing Co. All rights reserved.

Chabukswar V.V.,Nowrosjee Wadia College | Bhavsar S.V.,Nowrosjee Wadia College | Mohite K.C.,University of Pune
Journal of Macromolecular Science, Part A: Pure and Applied Chemistry | Year: 2012

In this paper, we report the synthesis of poly(N-ethylaniline) (PNETA) by using tartaric acid (TA) as an organic acid dopant by aqueous polymerization method of N-ethylaniline using ammonium per sulphate (APS) as an oxidant and acrylic acid (AA) as a soft template. This is a new polymerization method for the direct synthesis of the emeraldine salt form of poly(N-ethylaniline) in bulk quantity, which is soluble in organic solvents such as m-cresol and N-methyl pyrrolidinone. The prepared polymers were characterized by UV, FTIR, XRD, TGA, SEM and conductivity measurement studies. The results are discussed with reference to HCl doped poly(N-ethylaniline). It is observed that PNETA/TA/AA polymer is comparatively more soluble in m-cresol than that doped with HCl in its salt form. The formation of emeraldine salt phase and dopping process was confirmed by FTIR and UV-Vis spectroscropy. We demonstrate the effect of organic dopant on the morphology and conductivity of the PNETA. It was found that, PNETA doped with TA synthesized using acrylic acid (AA) as a soft template display higher doping level, crystallinity and solubility in common organic solvent. On the contrary, HCl doped polymer was lowered at doping level and amorphous in nature which reflects the role of organic dopant and soft template. X-ray diffraction studies indicate that the PNETA/TA/AA doped samples exhibit higher crystallinity, which indicates enhanced polymer sub-chain alignment as compared to HCl doped polymer. This is also manifested by the FTIR studies. SEM result also revealed the continuous morphology and sub-micrometer size, evenly distributed particles of the PNETA/TA/AA doped polymer. © 2012 Copyright Taylor and Francis Group, LLC.

Chabukswar V.,Nowrosjee Wadia College | Horne A.,Nowrosjee Wadia College | Bhavsar S.,Nowrosjee Wadia College | Mohite K.,University of Pune
Journal of Macromolecular Science, Part A: Pure and Applied Chemistry | Year: 2012

Synthesis of poly(o-anisidine) doped with various protonic acids by using ammonium persulphate as oxidizing agent were carried out in aqueous acid media. Influences of protonic acids on the physicochemical properties were investigated. The various process parameters were optimized to obtain poly(o-anisidine) in the conducting salt phase form. The results are discussed with references to different protonic acids. It was observed that poly(o-anisidine) is highly soluble in organic solvents, such as m-cresol and N-methyl pyrrolidinone (NMP). The polymers were characterized by UV-Visible, FTIR, SEM, XRD and conductivity measurements. A result shows that, different types of dopant acids HCl, H 2SO 4 and HClO 4 affect the morphology and electrical conductivity of the polymer. The electrical conductivity of the polymer follows the order HCl >H 2SO 4>HClO 4. Thus the effect of dopant ion type and the size of its negative ions influence the physico-chemical properties. UV-Vis absorption spectra shows peaks at 740-783nm with shoulder at 380-420nm as characteristic peaks for the emeraldine salt (ES) phase of poly(o-anisidine) POA. The FTIR spectra show a broad and intense band at ~2800-3001cm -1 and ~1159-1170cm -1 that account for the formation of ES phase of the polymer. The X-ray diffraction spectra show a characteristic peak at 20-30 o, 2 range which reveals partial crystalline structure. The conductivity of the poly(o-anisidne) salt was found to be in the range of 10 -3 to 10 -2 S/cm. SEM studies of poly(o-anisidine) doped with HCl shows the continuous granular uniform morphology with sub-micrometer evenly distributed particles of size ~ 100-200nm.Copyright © Taylor and Francis Group, LLC.

Dhorde A.A.,Nowrosjee Wadia College | Dhorde A.G.,University of Pune
Transactions of the Institute of Indian Geographers | Year: 2013

The present paper examines the inlet behaviour, in terms of the shifts in the inlet location over a span of last eight years (2002-2010), and its impact on the adjacent beach-dune complex. Valvati tidal inlet is observed to exhibit a strong instability in its location and is characterized by seasonal shifts in the ebb channel across the beach with a history of inlet migration over years. The zone of inlet shifts was demarcated and profiles were superimposed for four periods in order to understand the erosion/fill of the beach-dune complex. The Beach-dune complex in the north was found to be more stable and recorded less of variations whereas, the southern section of this complex (closer to the inlet) exhibited maximum variations. These variations were in terms of lowering of the dune crest and erosion on either side as well as formation of an extensive berm. A definite shifting pattern in the inlet location was observed to have direct impact on the lower section of the dune complex. Lowering and recession of the dune complex exhibited changes in the tidal prism at Valvati. The depth at the inlet throat reduced considerably by 2010 (1.24m) as against the 2008 (3m) condition. 2010 condition exhibited a tidal prism of 1.1 106 m3 as against a tidal prism of 9.2 106 m3 in 2008. A strong cyclicity, in terms of the inlet shifts, along with the inlet behavior induced changes in the adjacent beach-dune complex is thus ascertained for this region.

Sangpal R.,Nowrosjee Wadia College | Kulkarni U.,Nowrosjee Wadia College
Pollution Research | Year: 2013

An attempt has been made to study the effects of geochemical pollution in river water. It is revealed that the unsuitable physico-chemical characteristics triggered by thermal stratification accompanied by of river water led to a creation of a 'fatal zone' for the fish at village Pargaon in the Bhima basin (India). The environmental study of the river water quality suggests that the temporary bunds constructed across the river bed modified the aquatic environment. As a result, during the warm and dry climatic seasons, the temporary stagnant water conditions gave rise to reduction of dissolved oxygen (DO) and also increased toxicity. Simultaneous enhancement in thermal stratification lead to death of fish fauna at restricted locations. Conversely, there was abundance of such fish fauna in the downstream of the river and also in the back waters of the Ujjani dam, where identical physico-chemical and hydro-dynamic conditions existed except the thermal stratification. It is inferred that the addition of fresh water supply (both surface and ground water) from the adjacent region around Pargaon retained the sustainable conditions within water bodies. The lack of fresh water supply, thermal stratification and retention of toxicity are the root causes for the fish deaths. Such toxicity may be reduced by minimizing the thermal stratification and increasing the fresh water supply at the diseased sites.Copyright © EM International.

Jamdade P.G.,College of Engineering, Pune | Jamdade S.G.,Nowrosjee Wadia College
Lecture Notes in Electrical Engineering | Year: 2015

Proper representation of the wind speed and the mechanical torque is necessary in designing the wind turbine generator system (WTGS) and its components. This paper presents the effects of different wind speed profiles on mechanical torque output of the WTGS. Mechanical torque model consists of mathematical models of wind speed, mechanical power, mechanical torque and power coefficient of WTGS. For the case study purpose, wind speed data of Chalkewadi, Satara location, are used. Four different wind speed profiles are modelled according to the wind speed data of Chalkewadi, Satara location. WTGS is excited with the modelled wind speed profiles, and response to these wind speed profiles on mechanical torque produced by WTGS is observed. There is a reduction of 56 % in mechanical torque for three cases when compared to wind speed with all four designed components. The presented model, dynamic simulation and simulation results are tested in MATLAB/Simulink and presented. © Springer India 2015.

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