A5062583827- Atmospheric chemistry and aerosols
- Air Quality and Health Impacts
- Atmospheric aerosols and clouds
- Atmospheric Ozone and Climate
- Air Quality Monitoring and Forecasting
- Plant responses to elevated CO2
- Vehicle emissions and performance
- Atmospheric and Environmental Gas Dynamics
- Agricultural risk and resilience
- Agricultural Economics and Practices
- Indoor Air Quality and Microbial Exposure
- Energy and Environment Impacts
- Agriculture Sustainability and Environmental Impact
- Advanced Chemical Sensor Technologies
- Fire effects on ecosystems
- Botany, Ecology, and Taxonomy Studies
- Climate Change and Health Impacts
- Insect Pheromone Research and Control
- Industrial Gas Emission Control
- Global Energy and Sustainability Research
- Plant Water Relations and Carbon Dynamics
- Livestock Management and Performance Improvement
- Radioactivity and Radon Measurements
- Combustion and flame dynamics
- Sustainability and Ecological Systems Analysis
University of California, Irvine
2020-2023
Irvine University
2023
Quality Research
2020-2022
University of California, Davis
2020-2022
University of Hong Kong
2022
Southern California Earthquake Center
2020
University of Southern California
2020
Indian Institute of Science Education and Research Mohali
2013-2017
Abstract. One seventh of the world's population lives in Indo-Gangetic Plain (IGP) and fertile region sustains agricultural food crop production for much South Asia, yet it remains one most under-studied regions world terms atmospheric composition chemistry. In particular, emissions chemistry volatile organic compounds (VOCs) that form surface ozone secondary aerosol through photochemical reactions involving nitrogen oxides are not well understood. this study, ambient levels VOCs such as...
Abstract. In this study we use a high-quality data set of in situ ozone measurements at suburban site called Mohali the state Punjab to estimate ozone-related crop yield losses for wheat, rice, cotton and maize neighbouring Haryana years 2011–2013. We intercompare loss estimates according different exposure metrics, such as AOT40 (accumulated over threshold 40) M7 (mean 7-hour mixing ratio from 09:00 15:59), two major growing seasons kharif (June–October) rabi (November–April) establish new...
Abstract. The Kathmandu Valley in Nepal suffers from severe wintertime air pollution. Volatile organic compounds (VOCs) are key constituents of pollution, though their specific role the valley is poorly understood due to insufficient data. During SusKat-ABC (Sustainable Atmosphere for Valley–Atmospheric Brown Clouds) field campaign conducted winter 2012–2013, a comprehensive study was carried out characterise chemical composition ambient air, including determination speciated VOCs, by...
Abstract. A positive matrix factorization model (US EPA PMF version 5.0) was applied for the source apportionment of dataset 37 non-methane volatile organic compounds (NMVOCs) measured from 19 December 2012 to 30 January 2013 during SusKat-ABC international air pollution measurement campaign using a proton-transfer-reaction time-of-flight mass spectrometer in Kathmandu Valley. In all, eight categories were identified with new constrained operation mode. Unresolved industrial emissions and...
Abstract O 3 , CO, and NO x affect air quality tropospheric chemistry but factors that control them in the densely populated N.W. Indo‐Gangetic Plain (IGP) are poorly understood. This work presents first simultaneous 2 year long situ data set acquired from August 2011 to September 2013 at a IGP site (30.667°N, 76.729°E; 310 m asl). We investigate impact of emissions meteorology on diel seasonal variability . Regional post‐harvest crop residue fires contribute majorly an enhancement 19 ppb...
Abstract. Many sites in the densely populated Indo-Gangetic Plain (IGP) frequently exceed national ambient air quality standard (NAAQS) of 100 μg m−3 for 24 h average PM10 and 60 PM2.5 mass loadings, exposing residents to hazardous levels particulate matter (PM) throughout year. We quantify contribution long-range transport elevated PM number exceedance events through a back-trajectory climatology analysis masses arriving at IISER Mohali Atmospheric Chemistry facility (30.667° N, 76.729° E;...
Abstract. Biogenic volatile organic compounds (BVOCs) are important components of the atmosphere due to their contribution atmospheric chemistry and biogeochemical cycles. Tropical forests largest source dominant BVOC emissions (e.g. isoprene monoterpenes). In this study, we report total monoterpene flux measurements with a proton transfer reaction time-of-flight mass spectrometer (PTR-TOF-MS) using eddy covariance (EC) method at Tapajós National Forest (2.857∘ S, 54.959∘ W), primary...
Abstract Isoprene is a hydrocarbon emitted in large quantities by terrestrial vegetation. It precursor to several air quality and climate pollutants including ozone. Emission rates vary with plant species environmental conditions. This variability can be modeled using the Model of Emissions Gases Aerosols from Nature (MEGAN). MEGAN parameterizes isoprene emission as vegetation‐specific standard rate which modulated scaling factors that depend on meteorological driving variables. Recent...
Abstract. Plants emit a diverse range of biogenic volatile organic compounds (BVOCs) whose oxidation leads to secondary aerosol (SOA) formation. The majority studies SOA have focused on single or simple multicomponent BVOC mixtures thought be representative Northern hemispheric deciduous mixed forest conditions. Gaps remain in our understanding formation from complex real plant emissions other environments. Towards the goal regions, we conducted first comprehensive study oxygenated...
Abstract. The Kathmandu Valley in Nepal suffers from severe wintertime air pollution. Volatile organic compounds (VOCs) are key constituents of pollution, though their specific role the is poorly understood due to insufficient data. During SusKat-ABC (Sustainable Atmosphere for Valley-Atmospheric Brown Clouds) field campaign conducted winter 2012–2013, a comprehensive study was carried out characterize chemical composition ambient air, including determination speciated VOCs by deploying...
Abstract. A positive matrix factorization model (US EPA PMF version 5.0) was applied for the source apportionment of dataset 37 NMVOCs measured over a period 19 December 2012–30 January 2013 during SusKat-ABC international air pollution measurement campaign using Proton Transfer Reaction Time Flight Mass Spectrometer in Kathmandu Valley. In all, eight categories were identified with new "constrained operation" mode. Unresolved industrial emissions and traffic factors major contributors to...
Abstract. In this study we use a high quality dataset of in-situ ozone measurements at suburban site called Mohali in the state Punjab to estimate related crop yield losses for wheat, rice, cotton and maize neighbouring Haryana years 2011–2013. We inter-compare loss estimates according different exposure metrics such as AOT40 M7 two major growing seasons Kharif (June–October) Rabi (November–April) establish new relationship South Asian wheat rice cultivars. These are factor more sensitive...
Abstract. Biogenic volatile organic compounds (BVOCs) are important components of the atmosphere due to their contribution atmospheric chemistry and biogeochemical cycles. Tropical forests largest source dominant BVOC emissions (e.g. isoprene monoterpenes). In this study, we report total monoterpene flux measurements with a proton transfer reaction time-of-flight mass spectrometer (PTR-TOF-MS) using eddy covariance (EC) method at Tapajós National Forest (−2.857°S, −54.959°W), primary...
Abstract. A compound was observed using airborne proton transfer reaction time-of-flight mass spectrometry (PTR-TOF-MS) measurements in the emission plumes from Daesan petrochemical facility South Korea. The detected at m/z 43.018 on PTR-TOF-MS and tentatively identified as ketene, a rarely measured reactive volatile organic (VOC). Estimated ketene mixing ratios high ∼ 50 ppb (parts per billion) were plumes. Emission rates of estimated horizontal advective flux approach ranged 84–316 kg h−1....
Abstract. One seventh of the world population lives in Indo–Gangetic Plain (IGP) and fertile region sustains agricultural food crop production for much South Asia. Yet it remains one most under-studied regions terms atmospheric composition chemistry. In particular, emissions chemistry volatile organic compounds (VOCs) that form surface ozone secondary aerosol through photochemical reactions involving nitrogen oxides is not well understood. this study, ambient levels VOCs such as methanol,...
Abstract. Many sites in the densely populated Indo Gangetic Plain (IGP) frequently exceed national ambient air quality standard (NAAQS) of 100 μg m−3 for 24 h average PM10 and 60 PM2.5 mass loadings, exposing residents to hazardous levels PM throughout year. We quantify contribution long range transport elevated number exceedance events through a back trajectory climatology analysis masses arriving at IISER Mohali Atmospheric Chemistry facility (30.667° N, 76.729° E; 310 m a.m.s.l.) period...
We present reactive VOC observations over the North Pacific and Arctic Ocean from airborne shipborne measurements, investigating, in particular, distributions of biogenic volatile organic compounds that may be emitted phytoplankton. In contrast to terrestrial observations, isoprene (C5H8), most dominant BVOC emission ecosystem, was mostly under lower detection limit along with monoterpenes (C10H16), second largest ecosystem. However, we consistently detected sesquiterpenes (C15H24) for two...
The present paper has analyzed the mechanism by which farmers try to cope with supply-demand gap of agricultural labourers during busy seasons in face growing shortage labourers. traditional patron-client relationship between and been dealt this regard. In an attempt made find answer following questions: What is degree attachment employer? Is there any employer employee? How effective as a coping mitigate problem labourers? based on micro level study conducted six villages Uttar Dinajpur...