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Secondary organic aerosol from ozone-initiated reactions with terpene-rich household products

Description: We analyzed secondary organic aerosol (SOA) data from a series of small-chamber experiments in which terpene-rich vapors from household products were combined with ozone under conditions analogous to product use indoors. Reagents were introduced into a continuously ventilated 198 L chamber at steady rates. Consistently, at the time of ozone introduction, nucleation occurred exhibiting behavior similar to atmospheric events. The initial nucleation burst and growth was followed by a period in whi… more
Date: January 1, 2008
Creator: Coleman, Beverly; Coleman, Beverly K.; Lunden, Melissa M.; Destaillats, Hugo & Nazaroff, William W.
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Partner: UNT Libraries Government Documents Department
open access

Measurement of Black Carbon and Particle Number Emission Factors from Individual Heavy-Duty Trucks

Description: Emission factors for black carbon (BC) and particle number (PN) were measured from 226 individual heavy-duty (HD) diesel-fueled trucks driving through a 1 km-long California highway tunnel in August 2006. Emission factors were based on concurrent increases in BC, PN, and CO{sub 2}B concentrations (measured at 1 Hz) that corresponded to the passage of individual HD trucks. The distributions of BC and PN emission factors from individual HD trucks are skewed, meaning that a large fraction of pollu… more
Date: February 2, 2009
Creator: Ban-Weiss, George A.; Lunden, Melissa M.; Kirchstetter, Thomas W. & Harley, Robert A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Size-Resolved Particle Number and Volume Emission Factors for On-Road Gasoline and Diesel Motor Vehicles

Description: Average particle number concentrations and size distributions from {approx}61,000 light-duty (LD) vehicles and {approx}2500 medium-duty (MD) and heavy-duty (HD) trucks were measured during the summer of 2006 in a San Francisco Bay area traffic tunnel. One of the traffic bores contained only LD vehicles, and the other contained mixed traffic, allowing pollutants to be apportioned between LD vehicles and diesel trucks. Particle number emission factors (particle diameter D{sub p} > 3 nm) were f… more
Date: April 10, 2009
Creator: Ban-Weiss, George A.; Lunden, Melissa M.; Kirchstetter, Thomas W. & Harley, Robert A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Factors affecting the indoor concentrations of carbonaceous aerosols of outdoor origin

Description: A field study was conducted in an unoccupied single story residence in Clovis, California to provide data to address issues important to assess the indoor exposure to particles of outdoor origin. Measurements of black and organic carbonaceous aerosols were performed using a variety of methods, resulting in both near real-time measurements as well as integrated filter based measurements. Comparisons of the different measurement methods show that it is crucial to account for gas phase adsorption … more
Date: June 25, 2007
Creator: Lunden, Melissa M.; Kirchstetter, Thomas W.; Thatcher, Tracy L.; Hering, Susanne V. & Brown, Nancy J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Progress on building a predictive model of indoor concentrations of outdoor PM-2.5 in homes

Description: The goal of this project is to develop a physically-based, semi-empirical model that describes the concentration of indoor concentration of PM-2.5 (particle mass that is less than 2.5 microns in diameter) and its sulfate, nitrate, organic and black carbon constituents, derived from outdoor sources. We have established the methodology and experimental plan for building the model. Experimental measurements in residential style houses, in Richmond and Fresno, California, are being conducted to pro… more
Date: September 2001
Creator: Lunden, Melissa M.; Thatcher, Tracy L.; Littlejohn, David; Fischer, Marc L.; Kirchstetter, Thomas W.; Brown, Nancy J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The transformation of outdoor ammonium nitrate aerosols in theindoor environment

Description: Recent studies associate particulate air pollution with adverse health effects; however, the exposure to indoor particles of outdoor origin is not well characterized, particularly for individual chemical species. In response to this, a field study in an unoccupied, single-story residence in Clovis, California has been conducted. Real-time particle monitors were used both outdoors and indoors to quantify PM2.5 nitrate, sulfate, and carbon. The results show that reduced indoor sulfate and carbon … more
Date: January 31, 2002
Creator: Lunden, Melissa M.; Thatcher, Tracy L.; Littlejohn, David; Fischer, Marc L.; Hering, Susanne V.; Sextro, Richard G. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Indoor Secondary Pollutants from Household Product Emissions inthe Presence of Ozone: A Bench-Scale Chamber Study

Description: Ozone-driven chemistry is a major source of indoor secondary pollutants of health concern. This study investigates secondary air pollutants formed from reactions between constituents of household products and ozone. Gas-phase product emissions were introduced along with ozone at constant rates into a 198-L Teflon-lined reaction chamber. Gas-phase concentrations of reactive terpenoids and oxidation products were measured. Formaldehyde was a predominant oxidation byproduct for the three studied p… more
Date: October 1, 2005
Creator: Destaillats, Hugo; Lunden, Melissa M.; Singer, Brett C.; Coleman,Beverly K.; Hodgson, Alfred T.; Weschler, Charles J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Can combining economizers with improved filtration save energy and protect equipment in data centers?

Description: Economizer use in data centers is an energy efficiency strategy that could significantly limit electricity demand in this rapidly growing economic sector. Widespread economizer implementation, however, has been hindered by potential equipment reliability concerns associated with exposing information technology equipment to particulate matter of outdoor origin. This study explores the feasibility of using economizers in data centers to save energy while controlling particle concentrations with h… more
Date: June 5, 2009
Creator: Shehabi, Arman; Ganguly, Srirupa; Gundel, Lara A.; Horvath, Arpad; Kirchstetter, Thomas W.; Lunden, Melissa M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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