Research work and Publications

SUMMARY OF MY PH.D. RESEARCH WORK

During my Ph.D. thesis and post-doctoral periods at PRL, I have worked on new and challenging research projects to understand the emission and atmospheric processes of volatile organic compounds (VOCs) over South Asia. I also have significant experience in instrumentation, deployment, and field and laboratory experiments. In PRL, I have been using state-of-art and novel instruments such as high mass- and time-resolution proton transfer reaction-time of flight-mass spectrometer (PTR-ToF-MS), thermal desorption-gas chromatography-flame ionization detector (TD-GC-FID), and C2H6 and C5H16 VOCs analyzers to measure numerous VOCs in different environments over the land and ocean.

Experiences in Instrumentation, Deployment, Field, and Laboratory Experiments:

Operation and maintenance of PTR-TOF-MS and TD-GC-FID and up-gradation of laboratory
Facilities for comprehensive VOC measurements using C2H6 & C5H15VOC Analyzers.
Field Sampling and laboratory measurements of various non-methane hydrocarbons (NMHCs)
At a forest site in the Western Ghats (WG) during the late monsoon of 2016 and 2017.
Ship cruise campaign for the measurements of oceanic VOCs and other trace gases over the Arabian Sea during pre-monsoon season (April-May 2017).
Measurements of ambient VOCs near the Pirana landfill site of Ahmedabad during May 2017: Downwind dispersion and Air Quality impact.
Field Sampling and measurements of NMHCs in the temperate forest region (sub-Himalayan region) Uttarakhand, India, during the winter season of 2017.
Study of VOC emission flux in New Delhi: Eddy co-variance-based measurements of important VOC have been made using a high-time resolution PTR-TOF-MS instrument in New Delhi to understand the emission rates of VOCs from major urban sources. The Indo-UK project titled Megacity Delhi Atmospheric Emission Quantification, assessment, and Impact (DelhiFlux) (during 2017-2019).
Field campaign “Delhi Air Pollution and Health Effect” at New Delhi, India. Deployment and measurements of VOCs using PTR-TOF-MS and VOC Analyzers at urban and suburban sites of New Delhi (during 2018-19 and 2019-2020).
Ship cruise campaign for the measurements of oceanic VOCs and other trace gases over the Bay of Bengal (July-August 2018).
Continuous measurements of >50 VOCs to study the impact of COVID-19 lockdown during Jan-May 2020.
Field measurements of VOCs using PTR-TOF-MS and VOC Analyzers at an urban site of Lucknow, Uttar Pradesh, India, during winter and summer seasons (December 2020-May 2021).
Deployment of VOCs analyzers (C2 - C6, C5 - C15 and sulfur VOCs, DMS, CS2, etc.) at the Ship Sagar Kanya (ORV SK#373 for the measurements of different VOCs over the Bay of Bengal and the Arabian Sea during the post-monsoon season (September-November 2021).
Field campaign at IIT Delhi for the measurements of VOCs and change in the concentration of secondary VOCs after the photochemical aging of primary VOCs during the winter season (November- December 2021).

Experiences in Data Analysis:

Analysis of mass spectra of PTR-TOF-MS data retrieved in the ‘hdf’ format and Peak viewer software to extract the chromatogram data from GC-based instrument. I also use different software, e.g., MATLAB, MS Excel, Sigma, and Igor, and programming languages such as Python for advanced-level data analysis and graphics.

Collaboration:

IIT Kanpur and IIT Delhi,
CSIR - National Institute of Oceanography (NIO),
Centre for Marine Living Resources and Ecology (CMLRE),
Space Physics Laboratory (SPL),
National Physical Laboratory (NPL), and Centre for Ecology & Hydrology, Edinburgh, UK,
Paul Scherrer Institut (PSI), Switzerland.

List of Publications

Real-time measurements of non-methane volatile organic compounds in the central Indo-Gangetic basin, Lucknow, India: source characterization and their role in O3 and secondary organic aerosol formation, Vaishali Jain, Nidhi Tripathi, Sachchida N. Tripathi, Mansi Gupta, Lokesh K. Sahu, Vishnu Murari, Sreenivas Gaddamidi, Ashutosh K. Shukla, and Andre S. H. Prevot,
Atmospheric Chemistry and Physics, 23, 3383–3408, (2023)
Insights into the Regional Transport and Local Formation of Secondary Organic Aerosol in Delhi, India,
Himadri Sekhar Bhowmik, Sachchida Nand Tripathi, Ravi Sahu, Ashutosh Kumar Shukla, Vipul Lalchandani, Shamitaksha Talukdar, Nidhi Tripathi, Lokesh Sahu
Aerosol and Air Quality Research 22, 220113, (2022)
Characteristics of VOC composition at urban and suburban sites of New Delhi, India in winter,
Nidhi Tripathi, LK Sahu, Liwei Wang, Pawan Vats, Meghna Soni, Purushottam Kumar, RV Satish, Deepika Bhattu, Ravi Sahu, Kashyap Patel, Pragati Rai, Varun Kumar, Neeraj Rastogi, Narendra Ojha, Shashi Tiwari, Dilip Ganguly, Jay Slowik, André SH Prévôt, Sachchida N Tripathi
Journal of Geophysical Research: Atmospheres 127 (12), (2022)
Seasonal variability and source apportionment of non-methane VOCs using PTR-TOF-MS measurements in Delhi, India,
Vaishali Jain, Sachchida N Tripathi, Nidhi Tripathi, Lokesh K Sahu, Sreenivas Gaddamidi, Ashutosh K Shukla, Deepika Bhattu, Dilip Ganguly
Atmospheric Environment, 119163
Particulate Matter Pollution in Urban Cities of India During Unusually Restricted Anthropogenic Activities,
Ravi Yadav, Pushpendra Vyas, Praveen Kumar, Lokesh Kumar Sahu, Umangkumar Pandya, Nidhi Tripathi, Mansi Gupta, Vikram Singh, Pragnesh N Dave, Devendra Singh Rathore, Gufran Beig, SNA Jaaffrey
Frontiers in Sustainable Cities (2022)
Impact of COVID‐19 pandemic lockdown in ambient concentrations of aromatic volatile organic compounds in a metropolitan city of western India,
LK Sahu, Nidhi Tripathi, Mansi Gupta, Vikas Singh, Ravi Yadav, Kashyap Patel
Journal of Geophysical Research: Atmospheres 127 (6), (2022)
Effect of Biomass Burning on PM2.5 Composition and Secondary Aerosol Formation During Post‐Monsoon and Winter Haze Episodes in Delhi,
V Lalchandani, D Srivastava, J Dave, S Mishra, N Tripathi, AK Shukla, R Sahu, NM Thamban, S Gaddamidi, K Dixit, D Ganguly, S Tiwari, AK Srivastava, L Sahu, N Rastogi, P Gargava, SN Tripathi
Journal of Geophysical Research: Atmospheres 127 (1), (2022)
Investigation of major emission sources of non-methane hydrocarbons and their role in ozone formation in New Delhi, India,
Nidhi Tripathi, Lokesh Sahu, Mansi Gupta, Sachchida Tripathi,
AGU Fall Meeting Abstracts 2021, A55J-1524, (2022)
Air Pollution in New Delhi during Late Winter: An Overview of a Group of Campaign Studies Focusing on Composition and Sources,
Shamitaksha Talukdar, Sachchida Nand Tripathi, Vipul Lalchandani, Maheswar Rupakheti, Himadri Sekhar Bhowmik, Ashutosh K Shukla, Vishnu Murari, Ravi Sahu, Vaishali Jain, Nidhi Tripathi, Jay Dave, Neeraj Rastogi, Lokesh Sahu,
Atmosphere 12 (11), 1432, (2022)
Non-methane volatile organic compounds emitted from domestic fuels in Delhi: emission factors and total city-wide emissions,
Arnab Mondal, Ummed Singh Saharan, Rahul Arya, Lokesh Yadav, Sakshi Ahlawat, Ritu Jangirh, Garima Kotnala, Nikki Choudhary, Rubiya Banoo, Akansha Rai, Pooja Yadav, Martina Rani, Shyam Lal, Gareth J Stewart, Beth S Nelson, W Joe F Acton, Adam R Vaughan, Jacqueline F Hamilton, James R Hopkins, C Nicholas Hewitt, Lokesh K Sahu, Nidhi Tripathi, SK Sharma, Tuhin K Mandal
Atmospheric Environment: X 11, 100127, (2022)
Real-time quantification and source apportionment of fine particulate matter including organics and elements in Delhi during summertime,
Ashutosh K Shukla, Vipul Lalchandani, Deepika Bhattu, Jay S Dave, Pragati Rai, Navaneeth M Thamban, Suneeti Mishra, Sreenivas Gaddamidi, Nidhi Tripathi, Pawan Vats, Neeraj Rastogi, Lokesh Sahu, Dilip Ganguly, Mayank Kumar, Vikram Singh, Prashant Gargava, Sachchida N Tripathi,
Atmospheric Environment 261, 118598, (2022)
Ambient air characteristics of biogenic volatile organic compounds at a tropical evergreen forest site in Central Western Ghats of India