Browsing by Author "Pandey, Puneeta"

Filter results by typing the first few letters
Now showing 1 - 18 of 18
  • No Thumbnail Available
    Item
    Adsorption of Zn(II) on Pristine and SPLP/TCLP Leached Rice Straw Biochar: an Interplay of Precipitation and Ion Exchange
    (Institute for Ionics, 2022-11-15T00:00:00) Bhardwaj, Akanksha; Nag, Shilpa; Hussain, Khadim; Arora, Meenu; Pandey, Puneeta; Babu, J. Nagendra
    The inorganic mineral content in biochar influences the adsorption of Zn(II) metal ions. Metal ion adsorption on mineral rich rice straw biochar is influenced upon washing. Rice straw slow pyrolysis biochar BC1-3, respectively, prepared at 400, 500, and 600��C, were leached under Toxicity Characteristic Leaching Procedure (TCLP) and Synthetic Precipitation Leaching Procedure (SPLP) conditions to furnish BT1-3 and BS1-3, respectively. The Zn(II) adsorption studies were carried out for pH and dose optimization, initial concentration, isotherm fit, and kinetic studies. The Zn(II) adsorption by B(C/S/T)1�3 showed Langmuir and Freundlich isotherm, with pseudo-second-order kinetics at optimum pH 5 and dose 1�g/L. The adsorption of Zn(II) followed the trend BC3(qm 47�mg/g) > BC2 > BC1 > BS2 > BS1 > BS3 > BT2 > BT1 > BT3 (qm 3.5�mg/g), i.e., metal ion adsorption decreased with extent of leaching. The Zn(II) adsorption on biochar involved precipitation as dominant factor for metal ion adsorption on the biochars followed by ion exchange and proton exchange. The precipitation of Zn(II) ions in case of BC1-3 is attributed to the pH of biochar, which increases with proportion of minerals to organic content in biochar. In case of biochar BS1-3 and BT1-3, ion exchange and proton exchange mechanisms driven by demineralization are responsible for Zn(II) adsorption. The adsorption mechanism for Zn(II) on biochar is supported by XPS, solid state NMR studies. Graphical Abstract: [Figure not available: see fulltext.] � 2022, The Author(s), under exclusive licence to Springer Nature Switzerland AG.
  • No Thumbnail Available
    Item
    Air Pollution, Climate Change, and Human Health in Indian Cities: A Brief Review
    (Frontiers Media S.A., 2021-08-13T00:00:00) Kaur, Rajveer; Pandey, Puneeta
    Climate change and air pollution have been a matter of serious concern all over the world in the last few decades. The present review has been carried out in this concern over the Indian cities with significant impacts of both the climate change and air pollution on human health. The expanding urban areas with extreme climate events (high rainfall, extreme temperature, floods, and droughts) are posing human health risks. The intensified heat waves as a result of climate change have led to the elevation in temperature levels causing thermal discomfort and several health issues to urban residents. The study also covers the increasing air pollution levels above the prescribed standards for most of the Indian megacities. The aerosols and PM concentrations have been explored and hazardous health impacts of particles that are inhaled by humans and enter the respiratory system have also been discussed. The air quality during COVID-2019 lockdown in Indian cities with its health impacts has also been reviewed. Finally, the correlation between climate change, air pollution, and urbanizations has been presented as air pollutants (such as aerosols) affect the climate of Earth both directly (by absorption and scattering) and indirectly (by altering the cloud properties and radiation transfer processes). So, the present review will serve as a baseline data for policy makers in analyzing vulnerable regions and implementing mitigation plans for tackling air pollution. The adaptation and mitigation measures can be taken based on the review in Indian cities to reciprocate human health impacts by regular air pollution monitoring and addressing climate change as well. Copyright � 2021 Kaur and Pandey.
  • No Thumbnail Available
    Item
  • No Thumbnail Available
    Item
    Ambient noise levels due to dawn chorus at different habitats in Delhi. Environment and We: An
    (2011) Singh, Manoj; Kumar, Dinesh; Pandey, Puneeta; Kumar, Krishan; Jain, Vinod Kumar
  • No Thumbnail Available
    Item
  • No Thumbnail Available
    Item
    E-waste Management Practices in India: Challenges and Approaches
    (Springer International Publishing, 2023-03-01T00:00:00) Pandey, Puneeta; Singh, Raj Kumar
    In the current era of rising consumerism and information technology, e-waste has emerged as a serious problem besides plastic pollution. The rising concern for e-waste has both economic, environmental and health consequences. It is observed that wealthy nations with advanced technology dump their electronic waste disproportionately in developing nations. The management and recycling of waste in these developing countries is mostly carried out in informal sector, where workers (both adults and children) are exposed to health hazards. Further, the sound management practices, if not employed properly, are a cause of environmental concern. The present study attempts to throw some light on India�s issues in managing e-waste, the techniques available for e-waste management and legislations and international efforts in combating the menace of e-waste. � The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2023, corrected publication 2023.
  • No Thumbnail Available
    Item
    Effect of Pyrolysis Temperature on Mechanistic Transformation for Adsorption of Methylene Blue on Leached Rice-Straw Biochar
    (John Wiley and Sons Inc, 2022-02-09T00:00:00) Bhardwaj, Akanksha; Nag, Shilpa; Dahiya, Amarjeet; Pandey, Puneeta; Arora, Meenu; Babu, J. Nagendra
    Toxicity characteristic leaching procedure (TCLP) leached biochar is studied for adsorption of methylene blue (MB). Rice straw biochar obtained from slow pyrolysis at 400, 500, and 600��C, respectively, is TCLP leached to furnish leached biochar, BL4, BL5, and BL6. The leached biochar BL4�6 have been characterized for pH, CHN analysis, ash, zeta potential, surface area morphology and functional groups. Batch adsorption studies are optimized for pH (3�9), adsorbent dose (0.5�4�g�L?1), and initial MB concentration (20�135�mg�L?1). Nonlinear fitting to Langmuir, Freundlich, and Redlich-Peterson adsorption isotherm with due statistical treatment and error function analysis is carried out. Leached biochar, BL4, BL5, and BL6, is characterized by the dominance of carboxylic acid, lactone, and phenols moieties, respectively. The MB adsorption on leached biochar exhibits maximum adsorption of 26.87, 51.34, and 18.83�mg�g?1 for BL4, BL5, and BL6, respectively. The underlying mechanism for adsorption of MB using BL5, is characterized by non-ionic lactone ring opening in presence of MB under alkaline conditions that is supported by X-ray photoelectron spectroscopy(XPS) and Fourier transformed infrared spectroscopy (FTIR) studies. Desorption of MB and regeneration from BL5 is studied with methanol and 0.1 m HCl as stripping solvent for four cycles. Recovery of MB is better with methanol in comparison to 0.1 m HCl. � 2022 Wiley-VCH GmbH.
  • No Thumbnail Available
    Item
    Effect of temperature and fly ash content on the catalytically pyrolyzed rice straw biochar�fly ash composites for methylene blue adsorption
    (John Wiley and Sons Ltd, 2022-09-26T00:00:00) Bhardwaj, Akanksha; Nag, Shilpa; Hussain, Khadim; Pandey, Puneeta; Babu, J. Nagendra
    Rice straw and fly ash are the wastes produced in abundance which need immediate attention for their management. In the present study, the in situ pyrolysis of rice straw in presence of fly ash was carried out and the resultant composites were studied for adsorption of methylene blue (MB). Slow pyrolysis of rice straw in presence of fly ash is evaluated using thermogravimetric analysis (TGA) and Coats�Redfern equation for pseudo-first-order reaction kinetics, respectively. The activation energy (Ea) for the pyrolysis of rice straw was 41.75 kJ/mol which was lowered to 37.39 kJ/mol in presence of fly ash. Biochar fly ash composites BFA41�3, BFA51�3, and BFA61�3 were prepared at three 400�C, 500�C, and 600�C pyrolysis temperature, respectively, the subscript indicating three different ratios of rice straw and fly ash (1:3, 1:1, and 3:1 w/w ratio). The composites BF4�61�3 were neutral to alkaline in pH, due to the presence of basic oxide and carbonates minerals. BFA4�61�3 was studied for batch adsorption of MB and optimized for pH, dose, and initial concentration of adsorbate. The maximum MB adsorption capacity of 25.91 mg/g was reported for the composite BFA41. MB adsorption efficiency (qe) followed the trend BFA41�3 > BFA51�3 > BFA61�3, which indicates a strong influence of biochar surface functional groups on dye adsorption, as reiterated by the multiple linear regression (MLR) analysis. Stripping of MB was achieved using methanol as a stripping agent for MB-adsorbed BFA4�61�3 with desorption efficiency of 7% to 11% in the first cycle and 23% to 100% in the second cycle. Thus, the biochar fly ash composite with optimum ion exchangeable functional organic moieties would be suitable for dye remediation and waste generated in the process could find application in soil amelioration. � 2022 Curtin University and John Wiley & Sons Ltd.
  • No Thumbnail Available
    Item
    Influence of stubble burning on air quality of Northern India: a case study of Indo-Gangetic plains of India
    (Springer Science and Business Media Deutschland GmbH, 2023-03-20T00:00:00) Singh, Abhijeet; Vishnoi, Ashok Singh; Banday, Anwar Hameed; Bora, Pratyashee; Pandey, Puneeta
    Stubble burning is an emerging environmental issue in Northern India, which has severe implications for the air quality of the region. Although stubble burning occurs twice during a year, first during April�May and again in October�November due to paddy burning, the effects are severe during October�November months. This is exacerbated by the role of meteorological parameters and presence of inversion conditions in the atmosphere. The deterioration in the atmospheric quality can be attributed to the emissions from stubble burning which can be perceived from the changes observed in land use land cover (LULC) pattern, fire events, and sources of aerosol and gaseous pollutants. In addition, wind speed and wind direction also play a role in changing the concentration of pollutants and particulate matter over a specified area. The present study has been carried out for the states of Punjab, Haryana, Delhi, and western Uttar Pradesh to study the influence of stubble burning on the aerosol load of this region of Indo-Gangetic Plains (IGP). In this study, the aerosol level, smoke plume characteristics, long-range transport of pollutants, and affected areas during October�November from year 2016 to 2020 were examined over the Indo-Gangetic Plains (Northern India) region by the satellite observations. By MODIS-FIRMS (Moderate Resolution Imaging Spectroradiometer-Fire Information for Resource Management System) observations, it was revealed that there was an increase in stubble burning events with the highest number of events being observed during the year 2016 and then a decrease in the number of events in subsequent years from 2017 to 2020. MODIS observations revealed a strong AOD gradient from west to east. The prevailing north-westerly winds assist the spread of smoke plumes over Northern India during the peak burning season of October to November. The findings of this study might be used to expand on the atmospheric processes that occur over northern India during the post-monsoon season. The pollutant, smoke plume features, and impacted regions of biomass-burning aerosols in this region are critical for weather and climate research, especially given the rising trend in agricultural burning over the previous two decades. Graphical Abstract: [Figure not available: see fulltext.]. � 2023, The Author(s), under exclusive licence to Springer Nature Switzerland AG.
  • No Thumbnail Available
    Item
  • No Thumbnail Available
    Item
  • No Thumbnail Available
    Item
    A Review on Volatile Organic Compounds (VOCs) as Environmental Pollutants: Fate and Distribution
    (MRI Publication Pvt. Ltd., 2018) Yadav, Radheshyam; Pandey, Puneeta
  • Thumbnail Image
    Item
    Spatio – temporal variations of urban heat island over Delhi
    (Elsevier, 2014) Pandey, Alok Kumar; Singh, Sachchidanand; Berwal,Shivesh; Kumar, Dinesh; Pandey, Puneeta; Prakash,Amit; Lodhi, Neelesh; Maithani,Sandeep; Jain,Vinod Kumar; Kumar, Krishan
    Temporal and spatial trends of the surface urban heat island (UHI) formation over Delhi are examined with respect to aerosol load and land-cover variations. The study reveals that temperatures over Delhi are higher than those over the surrounding regions almost through-out the year during the night time. The nocturnal heat island intensity is minimum (0–2 K) during the monsoon months and maximum during the month of March (4–6 K). The UHI trends during the day-time are however, significantly different. It is observed that a day-time cool island forms over Delhi twice during the year in the months of May–June and October–December. Analysis of temporal variations in urban heat island intensity (UHII) and aerosol load over Delhi reveals a significant negative correlation between UHII and aerosol optical depth (AOD). Spatial analysis of LST, land-cover and AOD for the months of March, May and November confirms the significant role of AOD along with land-cover variables such as percentage area under the classes built-up, rock, vegetation and bare soil. Comparative analysis of LST in the regions lying north, south, east and west of Delhi in relation to the prevailing land-cover suggests that thermal inertia is also a very important factor determining the urban-rural thermal structure.
  • No Thumbnail Available
    Item
    Spatio-temporal assessment of imperious surfaces and their impacts on land surface temperature in bathinda city punjab
    (Central University of Punjab, 2016) Singh, Sangita; Pandey, Puneeta
    Experimental discovery of graphene has opened up the door for the researcher in the field of 2D materials. After the successful synthesis of the graphene, new classes of the 2D material are emerging. Phosphorene, single layer of Phosphorous atoms, is one of those materials which was recently discovered in year 2014. In present study, we have focused on the Blue-Phosphorene nanoribbons which is one of the stable allotrope of phosphorene. Our DFT-based calculations suggest the electronic properties of blue phosphorene nanoribbons to have strong dependence on the edge structure. The passivation plays important role in the electronic properties of the Blue Phosphorene nanoribbons. In our work, we have also performed the calculations for mechanical strength, width and strain depended electronic properties of the Blue Phosphorene nanoribbons. It was found that the zigzag phosphorene nanoribbon (ZPNR) possess more mechanical strength than the armchair phosphorene nanoribbon (APNR). The electronic band gap is found to be inversely proportional to the width of the nanoribbons. On applying mechanical strain, the band gap the nanoribbon decreases and at specific high value of strain semiconductor to metallic transition occur. Our results may finds applications in Nanoelectronic devices based on the phosphorene based nanoribbons.
  • No Thumbnail Available
    Item
    Substantial changes in Gaseous pollutants and health effects during COVID-19 in Delhi, India
    (PeerJ Inc., 2023-01-09T00:00:00) Singh, Bhupendra; Pandey, Puneeta; Wabaidur, Saikh Mohammad; Avtar, Ram; Kumar, Pramod; Rahman, Shakilur
    Background. Coronavirus disease has affected the entire population worldwide in terms of physical and environmental consequences. Therefore, the current study demonstrates the changes in the concentration of gaseous pollutants and their health effects during the COVID-19 pandemic in Delhi, the national capital city of India. Methodology. In the present study, secondary data on gaseous pollutants such as nitrogen dioxide (NO2), carbon monoxide (CO), sulfur dioxide (SO2), ammonia (NH3), and ozone (O3) were collected from the Central Pollution Control Board (CPCB) on a daily basis. Data were collected from January 1, 2020, to September 30, 2020, to determine the relative changes (%) in gaseous pollutants for pre-lockdown, lockdown, and unlockdown stages of COVID-19. Results. The current findings for gaseous pollutants reveal that concentration declined in the range of 51%�83% (NO), 40%�69% (NOx), 31%�60% (NO2), and 25%�40% (NH3) during the lockdown compared to pre-lockdown period, respectively. The drastic decrease in gaseous pollutants was observed due to restricted measures during lockdown periods. The level of ozone was observed to be higher during the lockdown periods as compared to the pre-lockdown period. These gaseous pollutants are linked between the health risk assessment and hazard identification for non-carcinogenic. However, in infants (0�1 yr), Health Quotient (HQ) for daily and annual groups was found to be higher than the rest of the exposed group (toddlers, children, and adults) in all the periods. Conclusion. The air quality values for pre-lockdown were calculated to be ��poor category to ��very poor�� category in all zones of Delhi, whereas, during the lockdown period, the air quality levels for all zones were calculated as ��satisfactory,�� except for Northeast Delhi, which displayed the ��moderate�� category. The computed HQ for daily chronic exposure for each pollutant across the child and adult groups was more than 1 (HQ > 1), which indicated a high probability to induce adverse health outcomes. � Copyright 2023 Singh et al.
  • No Thumbnail Available
    Item
    Temporal Variation of Water Quality Parameters during COVID-19: A Case Study of River Yamuna
    (2023-07-20T00:00:00) Singh, Bhupendra Pratap; Pandey, Puneeta; Koul, Monika; Bhatia, Bela; Singh, Amit Kumar; Mehra, Kriti; Chowdhary, Khyati; Kumar, Ranjeet; Goel, Vanshika
    Abstract: The novel coronavirus (COVID-19) originated in Wuhan city of China in late December 2019 and affected the (atmosphere and hydrosphere) and also impacted economic activities due to the lockdown. Several studies have reported the impact of the COVID-19 pandemic on significant changes in the air quality index, but only a few studies have reported the relationship between water quality parameters and COVID-19. The findings of the current study revealed that the mean values of pH in the Yamuna river were reported to be 7.77 � 0.31, 7.55 � 0.40, and 7.31 � 0.44 for pre-, during, and post-pandemic periods. The changes in the pH values indicated that Yamuna water quality became less alkaline due to restricted industrial activities along the river during the lockdown period. Further, the mean values of COD were observed to be 60.57 � 16.79, 62.99 � 23.17, and 129.06 � 36.96; the BOD values were 18.20 � 8.42, 20.16 � 5.22, and 33.35 � 10.35, and DO values were 3.30 � 1.15, 3.20 � 0.96, and 3.49 � 1.56 respectively for pre-, during, and post-pandemic periods. The results of these parameters indicated that agriculture, including local source discharges, was a major factor affecting water quality parameters during the pandemic period. According to the study, there is a significant positive association between the BOD and COD with values 0.99, 0.98, and 0.94, respectively, whereas a strong negative correlation was calculated between DO, COD, BOD for pre-, during, and post-pandemic periods. This study would be enlightening among the scientists, researchers, and government to address the water issues along with policy formulation. � 2023, Pleiades Publishing, Ltd.
  • No Thumbnail Available
    Item
    Tourism in Jammu and Kashmir: Economic growth and Environmental Consequences
    (New Century Publications, 2018) Ahmad, Naseer; Pandey, Puneeta
  • No Thumbnail Available
    Item
    WATERSHED CHARACTERISATION AND MANAGEMENT PLANNING OF HARIKE WETLAND USING REMOTE SENSING AND GIS APPROACH
    (Central University of Punjab, 2019) NAJAR, GH NABI; Pandey, Puneeta
    Wetlands are among the world’s most productive ecosystems and offer several beneficial services for man, fish and other wildlife. Despite the numerous valuable services provided by wetlands, they are overexploited throughout the world and particularly in developing countries. Hence their conservation and management has become a serious issue; and to restore them, conservational efforts at watershed level are most appropriate. Watershed planning approach adopted for wetland restoration provides dynamic benefits by restoring ecological processes and conserve water and soil resource integrity. In the present study, an attempt has been made to carry out a comprehensive analysis of Harike wetland and its catchment for various conservational measures and its sustainable management. The whole study area has been divided into 5 watershed basins, which were further subdivided into 25 sub-watersheds using Shuttle Radar Topography Mission (SRTM) data in conjunction with topographical maps of the study area. Morphometric parameters including linear parameters such as Stream number, Stream order (U), Stream Length (LU), Mean stream length (Lsm), Stream length ratio (RL), Bifurcation Ratio (Rb ); relief parameters such as Basin relief (Bh), Relief Ratio (Rh ), Ruggedness Number (Rn), Gradient ratio (Gh), Dissection index (Di); and aerial parameters namely: Drainage density (Dd), Drainage texture (T), Stream iv frequency (Fs), Form factor (Rf), Circulatory ratio (Rc), Elongation ratio (Re), Length of overland flow (Lg) and Constant channel maintenance(C) have been analysed to characterise the study area. The Morphometric analysis results revealed that study area as a whole has 7th stream order drainage basin as per the Strahler method. The sub-watershed ‘SWS11’ and ‘SWS12’ showed the smallest and largest basin area of 68.17 and 328.25 Km2 respectively. Among 25 sub-watersheds, SWS15 exhibit highest mean bifurcation ratio of 6.16. The drainage system of the basin is coarse with permeable subsurface strata and having moderate to good groundwater prospects. Landsat-8 Thematic Mapper (TM) and Linear Imaging Self Scanning Sensor-IV (LISS IV) satellite data of year 1995 and 2016 have been used to investigate the land use/ land cover (LULC) of Harike wetland and its catchment. On the basis of the spectral reflectance, seven major land use/land cover classes have been recognised namely; water, agricultural crop land, current follow land, wetland vegetation, wasteland, forest and built-up land. Agricultural land occupied the largest area in both the years of 1995 and 2016, covering an area of 74.55 and 66.16% respectively; whereas, forest occupied the lowest area of 0.13 and 0.10% respectively during the same time periods. Current fallow land exhibited the highest increase in total area followed by built up land. Different primary and secondary data were used to calculate the several parameters used in Revised Universal Soil Loss Equation (RUSLE). Length and Slope-factors (LS-factors) were calculated using data derived from Digital Elevation Model (DEM) in conjunction with topographical maps. Land use/land cover data prepared from LISS-IV satellite image (resolution of 5.8 m) have been used to calculate the Cover management-factor (C-factor). Average annual rainfall of last 15 years from year 2000 to 2015 of the study area have been used to prepare soil erodibility factor. SWS01 and SWS20 showed highest and lowest average annual soil loss of 12.22 and 3.20 t/ha/year respectively; whereas, average soil loss for whole study area was 5.03 t/ha/year. To have insights about groundwater recharge potential in the study area, groundwater potential zonation map was prepared using information from different raster layers including rainfall, slope, lineament density, soil, LULC, drainage density, geological and geomorphological maps. For the whole study area, groundwater potential recharge has been classified into five categories: poor, low, v medium, good and excellent based on infiltration potential. The moderate zone exhibits the highest percentage of 37.9 (1701 Km2 ). The area having excellent groundwater recharge potential is only 7.8% (350.13 km2 ). Further, groundwater recharge potential was analysed for all the 25 sub-watersheds of the study area, where, sub-watershed SWS03 covering large portion of the Harike wetland exhibited the highest area under excellent groundwater prospect zone (32.09%). In the present study an attempt has also been made to prioritise the different subwatersheds for soil and water conservation. Prioritization of sub-watersheds has been done based on soil erosion estimation and morphometric analysis and groundwater recharge prospect zonation. The results revealed that prioritization based on soil erosion estimation method is more appropriate than morphometric based method. Vulnerability of Harike wetland to weed infestation, encroachment and sediment deposition has been carried out based on the general impacts of LULC change, water quality and soil erosion on it. The present study describes the successful use of remote sensing and GIS for monitoring, characterisation and conservation of soil and water resources of the study area, using integrated watershed management approach for sustainable development.