A5024427589- Air Quality Monitoring and Forecasting
- Atmospheric chemistry and aerosols
- Spectroscopy and Laser Applications
- Air Quality and Health Impacts
- Atmospheric Ozone and Climate
- Vehicle emissions and performance
- Odor and Emission Control Technologies
- Atmospheric and Environmental Gas Dynamics
- Advanced Chemical Sensor Technologies
- Forest ecology and management
- Advanced Chemical Physics Studies
- Gas Sensing Nanomaterials and Sensors
- Laser Design and Applications
- Luminescence Properties of Advanced Materials
- Electrohydrodynamics and Fluid Dynamics
- Catalytic Processes in Materials Science
- Indoor Air Quality and Microbial Exposure
- Seedling growth and survival studies
- Inorganic Fluorides and Related Compounds
- Glass properties and applications
- Land Use and Ecosystem Services
- Atomic and Subatomic Physics Research
- Plasma Applications and Diagnostics
- Analytical Chemistry and Chromatography
- Urban Green Space and Health
National Physical Laboratory
2014-2024
Pace University
2017
Auburn University
2011-2013
Plant & Food Research
2005
Université Clermont Auvergne
1997-2001
Clermont-Ferrand’s Superior National School of Chemistry
1998-2001
Centre National de la Recherche Scientifique
1997-2001
University of Cambridge
1988-1993
University of Leicester
1972-1993
Hôpital Beaujon
1990
The emission angular distribution, total energy noise spectrum, and emitter life have been measured for the W/Zr thermal-field cathode. results give an in excess of 1000 h at T=1350 to 1450 K, P?2×10−8 Torr, a current ∼100 μA. A low-noise highly confined beam long (100) direction can be obtained. source brightness 1010 A/cm2 sr 3 kV spread less than 0.9 eV were under operational conditions.
The United States Environmental Protection Agency held an international two-day workshop in June 2018 to deliberate possible performance targets for non-regulatory fine particulate matter (PM2.5) and ozone (O3) air sensors. need a arose from the lack of any market-wide manufacturer requirement documented sensor evaluations, independent third party or government-based certification program, uncertainty among all users as general usability data. A multi-sector subject expert panel was...
Abstract. In times of growing concern about the impacts air pollution across globe, lower-cost sensor technology is giving first steps in helping to enhance our understanding and ability manage quality issues, particularly regions without established monitoring networks. While benefits greater spatial coverage real-time measurements that these systems offer are evident, challenges still need be addressed regarding reliability data quality. Given limitations imposed by intellectual property,...
We directly correlate the local (20-nm scale) and global electronic properties of a device containing mono-, bi-and tri-layer epitaxial graphene (EG) domains on 6H-SiC(0001) by simultaneously performing surface potential measurements using Kelvin probe force microscopy transport measurements.Using well-controlled environmental conditions, where starting state can be reproducibly defined, we investigate doping effects N2, O2, water vapour NO2 at concentrations representative ambient air.We...
Abstract. Ammonia (NH3) in the atmosphere affects both environment and human health. It is therefore increasingly recognised by policy makers as an important air pollutant that needs to be mitigated, though it still remains unregulated many countries. In order understand effectiveness of abatement strategies, routine NH3 monitoring required. Current reference protocols, first developed 1990s, use daily samplers with offline analysis; however, there have been a number technologies since,...
Abstract. Ambient air pollution poses a major global public health risk. Lower-cost quality sensors (LCSs) are increasingly being explored as tool to understand local problems and develop effective solutions. A barrier LCS adoption is potentially larger measurement uncertainty compared reference technology. The technical performance of various LCSs has been tested in laboratory field environments, growing body literature on uses primarily focuses proof-of-concept deployments. However, few...
The environmental impacts of ammonia (NH 3 ) in ambient air have become more evident the recent decades, leading to intensifying research this field.A number novel analytical techniques and monitoring instruments been developed, quality availability reference gas mixtures used for calibration measuring has also increased significantly.However, inter-comparison measurements show significant discrepancies, indicating that majority newly developed devices materials require further thorough...
The benefits of monitoring ambient air pollution with instruments mounted to ground-based, moving platforms include increased spatial resolution measurements and synchronous, fast-response close road sources for emissions analyses. However, these come at the cost obtaining a suitable number repeat visits each location in order achieve reliable representative estimates desired temporal resolution. Thus, methods that maximize information content derived from limited coverage mobile are needed...
The Auburn University campus in Auburn, Alabama, USA, was the location for a case study to compare carbon storage, sequestration, and air pollution (CO, O3, NO2, PM10, SO2) removal estimates between protected maintained urban forests. Results were from complete tree inventory i-Tree Eco analysis of 237 ha 5.5 areas campus. Trees landscapes had an average diameter at breast height 16.4 cm basal area 2.24 m2/ha when compared with 24.4 12.04 area. estimated store 6652 kg per sequester 291...
Abstract. When making measurements of air quality, having a reliable estimate the measurement uncertainty is key to assessing information content that an instrument capable providing, and thus its usefulness in particular application. This especially important given widespread emergence low cost sensors (LCS) measure quality. To do this, end users need clearly identify data requirements priori design quantifiable success criteria by which judge data. All suffer from errors, with degree these...
Titania nanostructures are of increasing interest for a variety applications, including photovoltaics, water splitting, and chemical sensing. Because the photocatalytical properties TiO₂, processes that occur at its surface can be exploited highly efficient nanodevices. A facile fast synthesis route has been explored is free catalysts or templates. An environmental scanning electron microscopy (ESEM) system was employed to grow titania nanowires (NWs) in vapor atmosphere (∼1 mbar) monitor...
We performed more than a year of mobile, 1 Hz measurements lung-deposited surface area (LDSA, the 20–400 nm diameter particles, deposited in alveolar regions lungs) and optically assessed fine particulate matter (PM2.5), black carbon (BC), nitrogen dioxide (NO2) central London. spatially correlated these pollutants to two urban emission sources: major roadways restaurants. show that optical PM2.5 is an ineffective indicator tailpipe emissions on roadways, where we do observe statistically...
Fourier transform infrared (FTIR) spectroscopy is increasingly used as a tool for volcano monitoring, allowing measurement of range gases including SO 2 , HCl, and HF. Retrievals are complicated, since the open‐path spectra typically pressure broadened contaminated hy atmospheric H O, CO etc., field instruments employed have low spectral resolution (∼0.5 cm −1 ). We present detailed analysis 0.5 certified mixtures in order to assess sensitivity such retrieval procedures spectra. investigate...
A UV pulsed laser writing technique to fabricate metal nanoparticle patterns on low-cost substrates is demonstrated. We use this process directly write gas sensors, which operate via quantum tunnelling of electrons at room temperature across the device. The advantages method are no lithography requirements, high precision placement, and processing in atmospheric conditions. Palladium-based sensors tested for detection water vapor hydrogen within controlled environmental chambers. electrical...
The Auburn University campus in Auburn, Alabama, U.S., was used as the site for a case study on applicability of i-Tree Eco using 100% tree inventory. 2009-2010 inventory managed areas encompassed 238 ha. Information collected from each included diameter at breast height (DBH), height, crown width, percent dieback, and condition rating. complete 7,345 trees with Lagerstroemia spp. (crapemyrtle), Quercus phellos (willow oak), Pinus taeda (loblolly pine) being most numerous species campus....