Vikas Goel - Academia.edu (original) (raw)

Papers by Vikas Goel

Viruses

The airborne transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has bee... more The airborne transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been identified as a potential pandemic challenge, especially in poorly ventilated indoor environments, such as certain hospitals, schools, public buildings, and transports. The impacts of meteorological parameters (temperature and humidity) and physical property (droplet size) on the airborne transmission of coronavirus in indoor settings have been previously investigated. However, the impacts of chemical properties of viral droplets and aerosol particles (i.e., chemical composition and acidity (pH)) on viability and indoor transmission of coronavirus remain largely unknown. Recent studies suggest high organic content (proteins) in viral droplets and aerosol particles supports prolonged survival of the virus by forming a glassy gel-type structure that restricts the virus inactivation process under low relative humidity (RH). In addition, the virus survival was found at neutral pH, and inac...

Environmental Pollution, 2020

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Chemosphere, 2021

h i g h l i g h t s g r a p h i c a l a b s t r a c t Concentration of BC varied from 0.22 to 16.... more h i g h l i g h t s g r a p h i c a l a b s t r a c t Concentration of BC varied from 0.22 to 16.92 mg/m 3 throughout the entire study period. BC concentration decreased up to 78% during lockdown as compared to pre-lockdown phase. Fossil fuel (BC ff) emissions dominated over those from biomass burning (BC bb). Trajectory and CWT analyses indicated maximum contribution from local sources.

In retrieval techniques, aerosol generally considered as chemically homogeneous spheres which res... more In retrieval techniques, aerosol generally considered as chemically homogeneous spheres which results in erroneous results. There is a severe need for multi-dimensional analysis of aerosol. Therefore, mineral dust particles were analyzed using focused ion beam (FIB) coupled with energy dispersive X-ray spectroscopy (EDS) and scanning electron microscopy (SEM). In present study, particle was observed in core-shell type structure, where shell was rich in Fe, Ca, C, Al, and Mg and core were rich in Si. In conventional SEM-EDS, the particle was observed as homogeneous mixture of Ca, Si, Cu, S, K, Mg, C, Fe and Al. Single scattering albedo (SSA) was calculated using FIB-SEM-EDS results and conventional SEM-EDS, difference between two results was observed to increase with increasing wavelength and the maximum difference was observed at 860 nm i.e. 19.38%. This shows that homogeneous spheres assumption is putting 19.38% uncertainty in results, which could have a tremendous effect on radiat...

Atmospheric Environment, 2018

Abstract Aerosols affect the Earth's radiation budget by interacting with the incoming solar ... more Abstract Aerosols affect the Earth's radiation budget by interacting with the incoming solar radiation. The physico-chemical properties, particularly morphological parameters (Aspect Ratio, AR and Circulatory Factor, CIR) and composition at individual particle level are important inputs to the optical model for assessing the optical sensitivity towards said properties. The observation of these properties is limited over Antarctica which has been studied in detail in the present work. The PM5 particles (particulate matter with aerodynamic diameter less than 5 μm) over Antarctica were collected at Indian Antarctic station, Maitri (70.77°S, 11.73°E) from Dec 2013–Feb 2014. The individual particle analysis revealed that particles were mainly composed of Si, Fe, Al, Ca and Mg. Most of the particles were observed in layered, flattened, aggregated and glass-like shapes. The frequency distributions of the morphological parameters, AR and CIR were observed to be bimodal with respective mode peaks 1.3 and 1.9 for AR; 0.4 and 0.7 for CIR. The spectral refractive indices of individual particles were estimated. The imaginary part of the refractive indices was observed to be maximum for chromium (Cr) and iron (Fe) rich particle and nearly negligible for aluminum (Al) rich particle. At 0.58 μm wavelength, the difference in SSA with respect to Al rich particle was found to be maximum for Ca rich particles (i.e. 43%) followed with Cr and Fe rich particle (i.e. 42.08%) and Cr rich particle (i.e. 39.32%).

Current Science, 2018

Road rationing policy, implemented in Delhi from 1 to 15 January 2016, reduced the traffic densit... more Road rationing policy, implemented in Delhi from 1 to 15 January 2016, reduced the traffic density. This particular event serves an opportunity to study the effect of reduced traffic density over particulate matter (PM) characteristics. The mean PM 2.5 and black carbon (BC) mass concentration before, during and after the event were observed as 163.51 μg/m 3 and 14.01 μg/m 3 , 186.98 μg/m 3 and 19.87 μg/m 3 , 197.45 μg/m 3 and 17.79 μg/m 3 respectively. During the first week (1-7 January 2016), high PM 2.5 mass concentration was observed while in the second week (8-15 January 2016), the concentration was relatively low. The concentration of elements like P, Cu, As and Pb was observed to be minimum during the event.