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Ambient particles are ubiquitous in the atmosphere and exert a strong influence on the climate by altering the Earth's radiative balance. Aerosol interactions with sunlight arise from their optical properties (e.g., scattering and absorption); however
In this issue, we highlight recent works that advance our understanding of physicochemical mechanisms governing nanoparticle (NP) deposition in the environment. In one study, the transport of citrate-stabilized silver NPs in an unsaturated porous medium
This publication provides guidelines for conducting radiometric calibrations of electro-optical (EO) sensors. It is intended for use by managers, technical oversight personnel, scientists, and engineers as a reference for planning and successfully
The first measurements of perfluorinated compounds (PFCs) in wildlife from the aqueous and terrestrial environment showed their ubiquitous presence. Since the initial studies in 2001 their presence, distribution, and fate in the environment has broadly
A new fundamental equation of state explicit in the Helmholtz energy is presented for 1,1,1,3,3 pentafluoropropane (R 245fa), based on recent experimental data for the vapor pressures, densities, and vapor sound speeds. The functional form now uses
Winnie K. Wong-Ng, James A. Kaduk, Daniel W. Siderius, Andrew J. Allen, Laura Espinal, Brad Boyerinas, Igor Levin, Matthew Suchomel, Jan Ilavsky, Eric J. Cockayne, Hui Wu
Cu-paddle-wheel-based Cu3(BTC)2 (nicknamed Cu-BTC, where BTC ≡ benzene 1,3,5-tricarboxylate) is a metal organic framework (MOF) compound that adopts a zeolite topology. We have determined the pore size distribution using the Gelb and Gubbins technique, the
Lucy J. Carpenter, Stefan Reimann, Andreas Engel, Stephen Montzka, James B. Burkholder, Cathy Clerbaux, Bradley Hall, Shari A. Yvon-Lewis, Donald R. Blake, Marcel Dorf, Geoffre S. Dutton, Paul J. Fraser, Lucien Froidevaux, Fran?ois Hendrick, Jianxin Hu, Ashley Jones, Paul B. Krummel, Lambert J. Kuijpers, Michael J. Kurylo, Qing Liang, Emmanuel Mahieu, Jens M?hle, Simon O?Doherty, Keiichi Ohnishi, Vladimir L. Orkin, Klaus Pfeilsticker, Matt Rigby, Isobel J. Simpson, Yoko Yokouchi
Changes in the global atmospheric abundance of a substance are determined by the balance between its emissions and removal. Declines observed for ozone-depleting substances (ODSs) controlled under the Montreal Protocol are due to global emission reductions
Laura Espinal, Martin L. Green, Dean M. DeLongchamp, Watcharop Chaikittisilp, Jarod C. Horn, Miles Sakwa-Novak, Cherno Jaye, Daniel A. Fischer, Nicholas Brunelli, Christopher Jones
Near edge x-ray absorption fine structure (NEXAFS) spectroscopy was used to study the adsorption of CO2 in a hyperbranched aminosilica (HAS) compound, a porous solid state material with great potential for carbon capture applications. After dosing a
Peter Ciesielski, Michael F. Crowley, M R. Nimlos, Aric Sanders, Gavin Wiggins, Bryon Donohoe
Biomass exhibits a complex microstructure of directional pores that can vary substantially between species of origin. However, models of biomass particles employed in simulations of conversion processes typically employ over-simplified geometry such as
P Key, K Chung, C Cooksey, DeLorenzo M, M Fulton, D Greenfield, T Greig, J Hylund, Bryant C. Nelson, Varun Patel, P Pennington, Elijah Petersen, E Wirth
NOAA's Environmental Sensitivity Index (ESI) lists saltmarshes along the Atlantic and Gulf Coasts as the most vulnerable habitat to oil spills. As a result of the Deepwater Horizon offshore drilling rig accident, more that 200 million gallons of crude oil
Bettye C. Johnson, Howard W. Yoon, Joseph P. Rice, Albert C. Parr
The fundamental concepts of optical radiometry are developed from basic principles, with detailed explanations for radiance, irradiance, and reflectance. Examples of radiometric standards, in particular radiometers and reference sources are given, and the
The safe use of nanocomposites depends, in part, on a good understanding of the fate of nanofillers throughout the nanocomposite‘s lifecycle. Various modifications of ISO weathering protocols have been proposed to assess what is released and at which rate
Vladimir L. Orkin, Victor Khamaganov, A G. Guschin
Rate constants for the gas phase reactions of OH radicals with three partially fluorinated ethers, CH3OCF3 (kHFE-143a), CH3OCHF2 (kHFE-152a), and CHF2OCH2CF3 (kHFE-245fa), were measured using a discharge flow electron paramagnetic resonance technique
Chun-Chieh Tien, Ching-Hsuan Chang, Bernard Hao-Chih Liu, Deborah Jacobs, Savelas A. Rabb, Lee L. Yu, Tinh Nguyen, Li Piin Sung
Polymer nanocoatings are increasingly used outdoors and in harsh environments. However, because most common polymers degraded by the weathering elements, nanoparticles in polymer nanocoatings may be released into the environments. Such nanoparticle release
Rodney A. Bryant, Olatunde B. Sanni, Elizabeth F. Moore, Matthew F. Bundy, Aaron N. Johnson
Point velocity measurements conducted by traversing a pitot tube across the cross section of a flow conduit continues to be the standard practice for evaluating the accuracy of continuous flow monitoring devices. Such velocity traverses were conducted in
John Bowden, Theresa M. Cantu, Douglas M. Scheidt, Russell H. Lowers, Brian A. Nocito, Vaneica Y. Young, Louis J. Guillette
Metal deposition originating from anthropogenic activity was examined in a two-tier study using environmental samples collected from several locations at the Kennedy Space Center (KSC) and surrounding Merritt Island National Wildlife Refuge (MINWR) with
Mark O. McLinden, Andrei F. Kazakov, J S. Brown, Piotr A. Domanski
We explore the possibilities for refrigerants having low global warming potential (GWP). A set of about 1200 candidate fluids is identified from more than 56 000 small molecules examaned by applying screening criteria to estimates for GWP, flammability
Russell D. Day, Paul R. Becker, O.F.X Donard, Rebecca S. Pugh, Stephen A. Wise
Environmental specimen banks (ESBs) have been a fundamental tool for many nations to monitor contaminant temporal and spatial trends, study fate and transport, and assess the severity and risks of pollution. The specimens archived in ESBs are among the
presentation at ASHRAE Winter Conference: We explore the possibilities for refrigerants having low global warming potential (GWP) through two distinct, but complementary, approaches. In an exploration of thermodynamic space we define the limits of what
Benjamin B. Parrott, John Bowden, Satomi Kohno, Jessica A. Cloy-McCoy, Jacqueline T. Bangma, Thomas R. Rainwater, Phillip M. Wilkinson, John Kucklick, Louis J. Guillette
Epigenetic modifications are key mediators of the interactions between the environment and an organism's genome. DNA methylation represents the best-studied epigenetic modification to date and is known to play key roles in regulating transcriptional
Vladimir L. Orkin, James B. Burkholder, Wahid Mellouki, Eric L. Fleming, Christian George, Charles H. Jackman, Timothy J. Wallington , Michael J. Kurylo , Dwayne E. Heard, William H. Swartz
Hydroxyl radical (OH), electronically excited atomic oxygen (O(1D)), and atomic chlorine (Cl) reaction rate coefficient data were evaluated and the estimated uncertainties in the recommended parameters reduced, in general, from those currently recommended
Environmental metabolomics is a rapidly growing area of research, and over the last decade the focus has been on organism responses to various types of environmental stressors (pollutants, nutritional shifts, and global climate change, for example)
Mark O. McLinden, Andrei F. Kazakov, J. Steven Brown, Piotr A. Domanski, Jae H. Heo
We explore the possibilities for refrigerants having low global warming potential (GWP) using two distinct, but complimentary, approaches. We evaluate the effect of a refrigerant's fundamental thermodynamic parameters on its performance in the simple vapor
This interim report summarizes research results to date under the FY2012 interagency agreement between CPSC and NIST to develop testing and measurement protocols for determining the quantities and properties of nanoparticles released from flooring finishes