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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Ceramic High Efficiency Particulate Air (HEPA) Filter Research and Development at Lawrence Livermore National Laboratory

Ceramic high efficiency particulate air (HEPA) filter development program began at Lawrence Livermore National Laboratory (LLNL) over 20 years ago. Historical incidents motivated current safety systems at nuclear facilities. A ceramic filter that can survive a fire can provide robust, passive safety protection. Research has been conducted to improve the safety of nuclear facilities and to reduce operational and lifecycle costs, through ceramic filter technology that can survive fire conditions. Here, the research focused on applications in both new facilities as well as meeting operational requirements necessary to retrofit filters into existing DOE facilities. The research has developed multiple filter technologies spanning traditional HEPA filter materials to advanced manufacturing technologies (e.g., electrospinning, additive manufacturing, etc.). This communication will present highlights of selected development efforts for ceramic HEPA filter research, current state-of-the-art for ceramic filters, and future needs including technical, regulatory, and commercial efforts.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2024

Establishing robust correction schemes for improved and reliable ARM-AOS aerosol optical data products

Aerosol light absorption and scattering of solar radiation play an important role in the earth’s atmosphere in terms of direct and semi-direct radiative forcing. Optical parameters of importance to the US Department of Energy (DOE) climate models include absorption and scattering coefficients, single scattering albedo (SSA), absorption Angstrom exponents (AAE), and the asymmetry parameter (g). These parameters depend on aerosol size, shape and composition (refractive index), and are spectrally sensitive in the shortwave region. Additionally, these parameters have a complex dependency on the emission source, especially for carbonaceous aerosols. The DOE Atmospheric Radiation Measurement (ARM) user facility has deployed aerosol observing systems (AOS) containing several filter-based instruments to measure and constrain aerosol optical properties and related parameters at multiple sites worldwide. For measurement of aerosol light absorption, the AOS includes filter-based instruments (particle soot absorption photometer and tricolor absorption photometer) that infer particle-phase aerosol absorption coefficients at nominal red, green, and blue wavelength bands from the attenuation (ATN) of light passing through a particulate filter on which aerosols are deposited. Measurement of aerosol scattering is done in situ using nephelometers. By combining inferred absorption coefficients from filter-based ATN measurements and in situ scattering coefficients, value-added products (VAPs) such as SSA, AAE, and g are derived.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2025

Research, Development and Demonstration of Advanced Vehicle Technologies in Clean Motor Fuels (CRADA Final Report)

NREL/DOE has been funding research, development, and demonstration (RD&D) projects to facilitate the deployment of alternative fuels into the marketplace in order to achieve three objectives: 1) enhance the reduction of mobile source emissions in California and the U.S.; 2) increase U.S. competitiveness and economic prosperity; and 3) preserve the environment through the reduction of emissions and toxins from the motor vehicle population. The Lewis-Presley Air Quality Management Act requires the South Coast Air Quality Management District to establish a program to encourage participation in projects to increase the utilization of clean-burning fuels. The parties seek to collaborate on a joint RD&D project to perform a field test on a small vehicle fleet operating on Fischer-Tropsch synthetic diesel fuel. Recently the 106th U.S. Congress designated "gas-to-liquid" (GTL) transportation fuels that are produced from domestic products as alternative fuels under the Energy Policy Act of 1992 (EPACT). Niche markets could develop quickly for these fuel products, perhaps especially for the use of Fischer-Tropsch synthetic fuels in centrally fueled vehicle fleets in California. NREL and its project partners from the U.S. Department of Energy and West Virginia University have recently conducted what we believe to be the first-ever controlled tests of Fischer-Tropsch synthetic fuels in heavy vehicles. These tests have shown that Fischer-Tropsch fuels can be substituted in unmodified trucks and buses without any detectable loss in drivability and performance. Compared to a California diesel fuel baseline, neat Shell Fischer-Tropsch fuel emitted about 12% lower NOx and 24% lower particulate matter over a five-mile driving route while maintaining the same fuel economy on an energy equivalent basis. Whereas these exhaust emissions reductions from these previous studies have been impressive, far greater exhaust emissions reductions can be achieved if the vehicles are retrofitted with emissions control technologies that are enabled by Fischer-Tropsch fuels. For this program, a test fleet would be selected and retrofitted with continuously regenerating traps (CRT’s) or diesel particulate filters (DPF's). The University of West Virginia, under a separate subcontract to SCAQMD will have the responsibility to test and measure the emissions from the test fleet of vehicles.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2026

Particulate Effluent Characterization (Final Report)

Understanding particulate emissions from nuclear facilities could help differentiate between normal nuclear operations and potential nuclear accidents or nuclear weapons tests. Oak Ridge National Laboratory (ORNL) is unique in that there are several types of nuclear facilities on site: an operating production reactor, radiochemical separation facilities, and a spallation neutron source. This project deployed a high-volume particulate air filter sampler to collect airborne particulate effluent from the nuclear facilities on site at ORNL. Collections occurred regularly from November 1, 2024, through June 30, 2025, and were analyzed via gamma spectroscopy in the laboratory. The radioisotope iodine-123 ( 123 I) was detected in several samples throughout the collection period. Detailed atmospheric transport modeling was performed on all detections for source attribution, and the most likely source of the 123 I was determined to be the Spallation Neutron Source. The project demonstrated the viability of ORNL as a test bed for effluent monitoring studies.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2025

Parametric Analysis of Holdup in HEPA Filters

This technical document (TECH) contains an analysis of several conditions deemed credible for plutonium oxide buildup in high-efficiency air particulate (HEPA) filters to determine the effect of holdup inside the filter on reactivity. This document is performed in accordance with NCS-AP-005, R3 [Ref. (1)].

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2024

Full Scale HEPA Filter Encapsulation in Ultra-High-Performance Grout - Proof of Concept

The Hanford Tank Waste Treatment and Immobilization Plant (WTP) currently being constructed to treat radioactive waste, includes vitrification facilities for both the high-level waste (HLW) and low activity waste (LAW) fractions. Operation of the WTP will produce contaminated high-efficiency particulate air filters (HEPA), as part of the solid secondary waste (SSW) stream. The HEPA filters receive off-gas from the vessel vent header and primary off-gas treatment system in LAW Facility and remove particulate contaminants including 99 Tc and 129 I salts. The current disposal method for HEPA filters is encapsulation in metal containers using cementitious material (CM) and disposal in the Integrated Disposal Facility (IDF). Results from the 2017 IDF Performance Assessment (PA) WRPS (2018) demonstrated that while compliance is maintained for the 1000 year compliance period mandated by DOE O 435.1 and its accompanying manual, release of constituents from the HEPA filters result in exceedance of the performance objective imposed as the groundwater regulatory limit at later times. For example, at about 1500 years post-closure, solid secondary waste (SSW), including HEPA filters is predicted to become a dominant contributor to 99 Tc release and over the 10,000-year sensitivity analysis period, SSW is the dominant contributor of 129 I release to the groundwater. The estimated release could potentially be reduced if the HEPA filters are not compacted and waste containers could be distributed throughout a large space, thereby diluting the contaminant release. Additionally, a better cementitious material could be used to encapsulate the HEPA filters. One alternative method for disposal of contaminated HEPA filters is encapsulation of the filters in ultra high-performance grout (UHPG). UHPG is a variation of ultra-high-performance concrete (UHPC) is commonly used in the prestressed concrete industry for large structural members. Recent studies of UHPG show it has excellent properties for containing radionuclides such as 99 Tc and 129 I Nichols and Kaplan (2021). This report presents the results of the first attempt to encapsulate a clean, full-size HEPA filter in UHPG and evaluate the effectiveness of the immobilization process and final waste form. A full-scale proof-of-concept simulated waste form was prepared by encapsulating a HEPA filter in a 110-gallon stainless steel (SS) drum using UHPG. A change from Type I/II PC to Type 1L PLC was made after American Rock Products informed the team that they would no longer be using Type I/II by the end of 2024 and the northwest was phasing out Type I/II PC overall. Type I/II PC used in previous studies of UHPG for encapsulation (Nichols and Kaplan 2021). After the UHPG was cured both the scaled mockup and the full-scale simulated waste forms were sectioned for visual examination. UHPG completely encapsulated the filters and bonded to the external surfaces of materials comprising the filters. No cracks were observed in the sectioned waste forms.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2024

Radiological Safety Analysis Computer Program V 7.2

Users generates a fission product inventory from either reactor operating history or a nuclear criticality event. RSAC-7 models the effects of high-efficiency particulate air filters or other cleanup systems and calculates the decay and ingrowth during transport through processes, facilities, and the environment. Doses are calculated for inhalation, air immersion, ground surface, ingestion, and cloud gamma pathways. RSAC-7 is used as a tool to evaluate accident conditions in emergency response scenarios, radiological sabotage events, and safety basis accident consequences.

Jordan, RobertaA. [Idaho National Laboratory (INL)↗
DOE OSTI2025

Radiological Safety Analysis Computer (RSAC) Program Version 7.4 Users’ Manual

The Radiological Safety Analysis Computer (RSAC) Program Version 7.4 (RSAC-7) is the newest version of the RSAC legacy code. RSAC-7 calculates the consequences of a release of radionuclides to the atmosphere. Users generates a fission product inventory from either reactor operating history or a nuclear criticality event. RSAC-7 models the effects of high-efficiency particulate air filters or other cleanup systems and calculates the decay and ingrowth during transport through processes, facilities, and the environment. Doses are calculated for inhalation, air immersion, ground surface, ingestion, and cloud gamma pathways. RSAC-7 is used as a tool to evaluate accident conditions in emergency response scenarios, radiological sabotage events, and safety basis accident consequences. This users’ manual contains the mathematical models and operating instructions for RSAC-7. Instructions, screens, and examples are provided to guide the user through the functions provided by RSAC-7. This program is designed for users who are familiar with radiological dose assessment methods.

73 - NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2026

Measured indoor PM2.5, black carbon, and oxidative potential before and after replacing gas with induction cooking in asthmatic households

Cooking is a major source of fine particulate matter (PM) in homes and evidence to date is inconclusive about the impact of cooking fuel on measures of residential PM exposure. The Cooking Energy and Ventilation Impacts on Children's Asthma (CEVICA) study measured cooking frequency, range hood use, indoor air quality (IAQ) and respiratory health indicators of children with asthma living in homes with gas stoves in California's San Joaquin Valley. Intensive measurements occurred over three 2-week intensive periods: at baseline and at the end of two consecutive 3-month study phases. Participants were randomly assigned to have their gas stoves replaced with electric induction at the start of Phase 1 or Phase 2. As part of the IAQ assessment, we collected particulate matter on Teflon filters using ultrasonic personal air samplers (UPAS). The filters were analyzed to quantify time-integrated PM 2.5 mass concentration, black carbon (BC) oxidative potential (OP). OP was measured using the SLF-OH assay, an acellular chemical assay that quantifies production of OH radicals in simulated lung fluid (SLF). Across all comparisons, PM 2.5 mass tended to be higher during gas cooking than induction electric cooking, although only one transition (Baseline to Phase 1) was statistically discernible at p<0.05. BC and mass-normalized OP showed no measurable differences across stove types or across phases. These preliminary findings suggest that stove fuel alone may not be the dominant determinant of indoor PM 2.5 concentrations in this sample, as previous studies have reported that indoor PM 2.5 during cooking can also be influenced by factors such as cooking practices, food and oil type, kitchen ventilation, and outdoor infiltration.

Lin, Zhuoying↗
DOE OSTI2026

Evaluation of a catalytically aided thermal regeneration method for quartz filter-based black carbon sensing

Black carbon (BC)–a strong indicator of diesel particulate matter and other sources of incomplete carbonaceous fuel combustion–is an important air pollutant that affects public health, yet low-cost sensors capable of long-term, autonomous BC monitoring remain underdeveloped. We report on the development and evaluation of a novel BC prototype sensor that integrates soot collection on a quartz filter, in-situ optical transmission measurement, and thermal filter regeneration. To enable regeneration at lower temperatures, we evaluated the catalytic effects of various alkali metal salts pre-applied to the filter. Among these, cesium carbonate (Cs 2 CO 3 ) exhibited the strongest catalytic activity, lowering the temperature required for complete BC removal by up to 190 °C and reducing energy consumption by more than 75% compared to that required for untreated filters. The catalytic effect persisted through 10 BC collection–regeneration cycles. These findings demonstrate the potential of catalytically aided thermal regeneration in BC sensors and suggest a pathway toward energy-efficient and reduced maintenance air quality monitoring suitable for distributed BC monitoring networks.

Tang, Xiaochen [Lawrence Berkeley National Laborat↗
DOE OSTI2024

PM2.5 Active Aerosol Collection Field Campaign Report

The long-range transport of aerosols can affect local air quality as well as contribute elements and constituents to mountain watersheds that have potentially positive (e.g., nitrate) and negative (e.g., heavy metals) effects to the local ecosystem. Isotopic analysis of aerosols can be a powerful tool for deconvolving the relative contributions of far-distant and local sources to the composition of collected aerosols. Our field campaign involved the week-long collection of PM2.5 (i.e., particulate matter with an aerodynamic diameter of about 2.5 microns) aerosols on filters, which were returned to the laboratories at Lawrence Berkeley National Laboratory (LBNL) for analysis. The sampling sites were located at the Gothic, Colorado Surface Atmosphere Integrated Field Laboratory (SAIL) Atmospheric Radiation Measurement (ARM) and the Mt. Crested Butte, Colorado SAIL ARM sites. The original intention was to measure the lead (Pb) and strontium (Sr) isotopic compositions of the collected aerosols at high precision to provide constraints on source portioning and attribution, as well as analyze the chemical compositions and nitrogen and carbon isotopic compositions. However, severe blank issues arose that prevented the planned isotopic analyses of Sr, Pb, C, and N and severely affected the analyses of the bulk chemical compositions of the collected aerosols, resulting in the failure of the study. The issue is described in Section 2.0.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2025

SAVY O-ring characterization for lifetime extension

Los Alamos National Laboratory and Nuclear Filter Technology, Inc. developed the SAVY-4000 nuclear material storage container, named after the designers Stone, Anderson, Viers, and Yarbro. The SAVY 4000 meets the requirements of Department of Energy (DOE) M 441.1-1,2 Nuclear Material Packaging Manual, to protect workers who handle nuclear materials against radiation exposures resulting from the leakage of stored materials. The SAVY-4000 is an innovative and creative design: it can be opened and closed in a few seconds without using torque wrenches and instead only a tire iron or equivalent prying tool; has a built-in, fire-rated filter that prevents the build-up of hydrogen gas yet retains 99.97% of plutonium particulates at 200 ACCM rated flow; and prevents the release of stored materials upon a 12- foot drop.

42 ENGINEERING↗
DOE OSTI2026

Assessing Options for Particulate Measurement Tools to Advance Wood Heaters (CRADA Final Report)

For approximately 40 years, particulate matter (PM) from residential wood heaters has been certified in North America using an EPA dilution tunnel with a filter-based gravimetric measurement. While reasonably repeatable, this approach reports only a single value for the entire burn sequence and does not provide information on PM at different points within the sequence, which would support improved wood heater designs. PM monitors that report with high time resolution offer a potential solution, but their performance for various types of heaters and across heater operating conditions has not been extensively evaluated. In this 18-month collaborative project, the Hearth, Patio & Barbecue Association (HPBA) and Lawrence Berkeley National Laboratory (LBNL) tested five continuous PM instruments spanning three measurement principles—light-scattering, inertial mass (TEOM), and triboelectric—against gravimetric and size-resolved references on three residential heater types (cordwood, catalytic cordwood, and pellet) across startup, high-burn, and low-burn operating phases.

42 ENGINEERING↗
DOE OSTI2024

Online characterization of primary and secondary emissions of particulate matter and acidic molecules from a modern fleet of city buses

The potential impact of transitioning from conventional fossil fuel to a non-fossil-fuel vehicle fleet was investigated by measuring primary emissions via extractive sampling of bus plumes and assessing secondary mass formation using the Gothenburg Potential Aerosol Mass (Go:PAM) reactor from 76 in-use transit buses. Online chemical characterization of gaseous and particulate emissions from these buses was conducted using chemical ionization mass spectrometry (CIMS) with acetate as the reagent ion, coupled with the Filter Inlet for Gases and AEROsols (FIGAERO). Acetate reagent ion chemistry selectively ionizes acidic compounds, including organic and inorganic acids, as well as nitrated and sulfated organics. A significant reduction (48 %–98 %) in fresh particle emissions was observed in buses utilizing compressed natural gas (CNG), biodiesels like rapeseed methyl ester (RME) and hydrotreated vegetable oil (HVO), and hybrid-electric HVO (HVO HEV ) compared to diesel (DSL). However, secondary particle formation from photooxidation of emissions was substantial across all the fuel types. The median ratio of particle mass emission factors of aged to fresh emissions increased in the following order: DSL buses at 4.0, HVO buses at 6.7, HVO HEV buses at 10.5, RME buses at 10.8, and CNG buses at 84. Of the compounds that can be identified by CIMS, fresh gaseous emissions from all Euro V/EEV (Enhanced Environmentally friendly Vehicle) buses, regardless of fuel type, were dominated by nitrogen-containing compounds such as nitrous acid (HONO), nitric acid (HNO 3 ), and isocyanic acid (HNCO), alongside small monoacids (C 1 –C 3 ). Notably, the emission of nitrogen-containing compounds was lower in Euro VI buses equipped with more advanced emission control technologies. Secondary gaseous organic acids correlated strongly with gaseous HNO 3 signals (R 2 =0.85–0.99) in Go:PAM, but their moderate to weak correlations with post-photooxidation secondary particle mass suggest that they are not reliable tracers of secondary organic aerosol formation from bus exhaust. Our study highlights that non-regulated compounds and secondary pollutant formation, not currently addressed in legislation, are crucial considerations in the evaluation of environmental impacts of future fuel and engine technology shifts.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2026

Field Evaluation of Do-It-Yourself Air Filtration Solutions for Evaporative Coolers to Reduce Ambient Particle Infiltration in Homes in Wildfire-Affected Communities

Evaporative coolers (ECs) introduce outdoor air pollutants indoors when operating. This study evaluates the potential of do-it-yourself (DIY) air filtration solutions for ECs to cost-effectively reduce the infiltration of ambient fine particulate matter (PM2.5) in homes with ECs using measurements in 48 homes in wildfire-affected agricultural communities in California. All homes received one portable air cleaner (PAC); 25 homes also received DIY filters (mostly MERV 13) attached to their ECs. PurpleAir monitors measured indoor and outdoor PM2.5 concentrations. PAC operation was monitored in all of the homes. EC usage was monitored in some homes and predicted using relative humidity dynamics in all homes. Conditional analyses between EC likely on and off conditions were used to evaluate the impacts of DIY EC filters on ambient PM2.5 infiltration, including during several wildfire-affected days. Median levels of ambient PM2.5 infiltration increased ∼36-42% in homes with only PAC interventions when ECs were likely operating compared to only ∼10-11% in homes with both PACs and DIY EC filters. Pre/postintervention comparisons in a subset of homes confirmed PM2.5 infiltration reductions. EC filter performance declined after extended use. Results suggest that short-term EC filter deployments are likely a cost-effective way to mitigate wildfire smoke infiltration inside these homes.

Wang, Mingyu↗
DOE OSTI2025

Advancing Aerosol Chemical Characterization and Vertical Profiling over the Southern Great Plains Using Uncrewed Aerial Sampling and Offline Aerosol Mass Spectrometry

Recent advancements in uncrewed aerial systems (UASs) and particulate matter (PM) analytical techniques have provided opportunities for atmospheric research. In this study, we deployed the Department of Energy’s fixed-wing ArcticShark UAS to examine PM 2.5 composition at varying altitudes─within and above the planetary boundary layer (PBL)─over the Southern Great Plains atmospheric observatory (SGP). A total of 22 flights were conducted across March, June, and August 2023. Composite filter samples were collected during each flight and analyzed with offline aerosol mass spectrometry (AMS), complemented by on-board real-time sensors and ground-based instrumentation, to provide a comprehensive view of regional aerosol characteristics. Results show clear vertical and seasonal differences in the aerosol composition. Relative to ground-level measurements, aloft samples exhibited shifts in the distribution of organic and inorganic PM, with the organic composition varying distinctly across seasons. Particulate organic nitrogen (ON) was elevated, with bulk compositions similar in March and June but strongly altered in August, likely driven by biomass burning and enhanced photochemical activity. Combined AMS and chemical ionization mass spectrometry analyses detected amines, amides, and amino acids. PM above the planetary boundary layer was enriched in oxidized organic aerosols, while ground-level PM contained higher nitrate and sulfate. Seasonal differences in aqueous-phase processing were also observed, which were strongest in March during persistent cloud cover and weaker in the drier August period, suggesting a shift from aqueous- to gas-phase SOA formation. In conclusion, these findings highlight the value of UAS in advancing PM measurements and vertical profiling of aerosol composition.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2026

Alpha-Imaging Detector System Development for Large Area Monitoring

Effective management and disposal of legacy nuclear waste are essential for ensuring safe work environments and minimizing environmental impacts. Monitoring airborne actinide contamination is particularly critical due to the high internal dose potential of alpha-emitting radionuclides. Traditional continuous air monitoring systems (CAMs) used in the industry are limited in the volume of air they can sample, potentially leading to inaccurate radiation detection over large areas. For example, in 2018, elevated levels of airborne Plutonium-239 were detected beyond the controlled areas of the Hanford Plutonium Finishing Plant, highlighting the potential risks to both plant workers and nearby residents. To address these challenges, high-efficiency particulate absorbing (HEPA) air purifiers can enhance air flow by up to 1.5 orders of magnitude, thereby increasing monitoring efficiency and providing a cost-effective solution for large-area surveillance. To quantify the activities of alpha-emitting radionuclides on HEPA filters, the Savannah River National Laboratory is developing an advanced alpha-imaging detection system. This system includes scintillating materials combined with a digital scientific camera. A significant concern in operating such a large-area airborne monitoring system is the handling of HEPA filters, which may be contaminated with radioactive particles. To mitigate these hazards, it is crucial to ensure that any contamination is securely fixed onto the filters. Efforts have been made to optimize the sensitivity of scintillator-epoxy composites and apply them to HEPA filters. These materials were characterized using fluoroscence spectroscopy. These techniques confirmed the purity of the raw materials, the dispersion of scintillators in the epoxy matrix, and the stability of their optical and structural properties post-modification. The optimal scintillator-epoxy composite was selected for use on alpha-spiked HEPA filters to evaluate the efficiency of the sprayer. HEPA filters, embedded with alpha particles collected by an air purifier deployed in an airborne radiation area, have been tested to assess detection efficiency. Future work will focus on employing multiple imaging sensors simultaneously to enhance sensitivity across different regions of the HEPA filter.

Pham, Phuong [Savannah River National Laboratory (↗
DOE OSTI2025

Studies of optical and chemical properties of aged and fresh biomass burning absorbing aerosols for climate models

Particulate emissions from burning fuels from sub-Saharan Africa is currently poorly characterized. With increasing population and industrialization, emissions are expected to grow. Optical methods for measuring light absorption in the ultraviolet (UV) and visible (vis) regions of the spectrum are crucial for understanding the optical properties of BB aerosols (Bond and Bergstrom, 2006; Lack and Cappa, 2010; Moschos et al., 2021). One such instrument is the dual-spot AE33 model aethalometer is a common filter-based instrument that can be used to measure aerosol absorption properties (Hansen et al., 1984). This instrument has many figures of merit; however, the method's limitations include potential biases from scattering within the filter material, multiple scattering effects of the particles, filter loading (i.e. particle shadowing), and the need for wavelength-specific correction factors (Cλ), which depend on accurate intercomparison with other in situ techniques (Bond et al., 1999; Collaud Coen et al., 2010). This work aims to: 1. Optically characterize BB aerosol generated from African fuel 2. Correct the aethalometer at multiple wavelengths 3. Parametrize these correction factors. 4. Combusting the same fuels with two difference tube furnace systems assess the general applicability of this flexible means of producing BB aerosol. This was accomplished by conducting laboratory studies at Los Alamos National Laboratory (LANL) and North Carolina A&T State University (NCA&T), where aethalometer measurements were compared to in situ optical measurements. Mass cross sections of BB aerosol from these under-studied fuels will be determined along with their wavelength dependence.

09 BIOMASS FUELS↗