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Completed Projects are listed under the following sub-categories:
Agricultural Burning
CREATING A STATEWIDE SPATIALLY
AND TEMPORALLY ALLOCATED AGRICULTURAL BURNING EMISSIONS INVENTORY USING CONSISTENT EMISSION
FACTORS. Principal Investigator: Peng Gong. University of California, Berkeley. 2002. 99-714.
CREATING A STATEWIDE SPATIALLY
AND TEMPORALLY ALLOCATED WILDFIRE AND PRESCRIBED BURN EMISSION INVENTORY USING CONSISTENT EMISSION FACTORS. Principal Investigator: Peng
Gong. University of California, Berkeley. 2001. 98-726
AIR POLLUTION FROM FOREST AND
AGRICULTURAL BURNING. Principal Investigator: Ellis F. Darley. University of California.1974. 2-017-1.
DETERMINATION OF TEMPERATURE,
WINDS AND PARTICULATE CONCENTRATIONS IN CONNECTION WITH OPEN FIELD BURNING. Principal Investigator: John J.
Carroll. 1973. University of California,
Davis. ARB-2114.
Air Quality
QUANTITATIVE ANALYSIS OF
AEROSOL TIME-OF-FLIGHT MASS SPECTROMETRY
DATA USING YAADA. Principal Investigator: Jonathan O.Allen. Arizona
State University. 2004. 01-338
ANALYSIS OF WEEKDAY/WEEKEND
DIFFERENCES IN AMBIENT AIR QUALITY AND METEOROLOGY IN THE SOUTH COAST AIR
BASIN. Principal Investigator: Warren Blier. University of California,
Los Angeles.1999. 95-334.
Objectives: To determine
weekend/weekday differences in emissions and ambient air quality,
including implications for carryover of ozone-forming pollutants from
weekdays to weekend days, and meteorological conditions of the South
Coast Air Basin (SoCAB) influenced by human activities.
Findings:This is the second
study to investigate day-of-the-week effects, where weekend days have
higher ozone concentrations coincident with lower precursor
emissions. Data suggests that the carryover of pollutants may
be of greater significance from Friday evening to Saturday than for
other days of the week. Limited ground observations suggest a
weak carryover effect for oxides of nitrogen (NOx) and nitrogen dioxide
(NO2. Day-of-the-week effect does not provide evidence that
further NOx control is counterproductive to further ozone reductions.
During 1994-5 Saturdays and Sundays, concentration reductions of
non-methane hydrocarbons (NMHC) and NOx coincided with increases in
ozone. However, 1986-96 ozone concentrations declined
significantly coincident with significant reductions in levels of NMHC
and NOx. A weak day-of-the-week influence was noted for
aerosol concentrations and ambient temperatures, indicating some impact
attributed to human activities. Additionally, recent years
seem to indicate a shift to later and short ozone seasons, with Sunday
becoming the highest ozone peak day-of-the-week.
Importance
to ARB’s Program: This research provided the ARB with
insights into the interaction between uniform emissions control
strategies and non-uniform ozone concentration reductions.
Results from this study are useful in judging the effectiveness of
current ozone control strategies. In addition, these data are
especially helpful in evaluating and addressing future air quality
needs in the SoCAB.
TEMPORAL, SPATIAL, AND AMBIENT
TEMPERATURE EMISSION EFFECTS
IN THE SACRAMENTO MODELING REGION. Principal Investigator:
David M. Rocke. University of California, Davis.1998.
94-333.
Objectives: To investigate
important temporal and spatial variations in emissions in the
Sacramento modeling region, specifically from non-road mobile sources
and industrial surface coatings and related process solvents, and to
assess the effect of ambient temperature on emissions from those
sources.
Findings: A GIS-based
approach was developed by the investigators to spatially allocate
regional or county-level emissions to units such as the grid cells that
are used in photochemical air quality simulation models. They also
developed statistical models by which the values of spatial surrogates
can be estimated and updated using widely available data on land use
and population and the U.S. Census Bureau's topographically integrated
geographic encoding and referencing files. The effects of
ambient temperature and weather on the source activities were estimated
based on the investigators' survey data and emissions estimates made by
the ARB.
Importance
to ARB’s Program: Information on temporal and spatial
distributions of emissions is important to air quality monitoring,
emissions inventory development, and air quality simulation and
modeling. The results of this study will allow the emissions
inventory for the Sacramento area to better reflect these variations
and provide insights into ways to improve emissions inventories for
other areas of the state. This is of importance for air
pollution control districts and the U.S. EPA. The results of
this study will be also of use in industries that use coatings,
businesses or farms that use light- or heavy-duty equipment, and
businesses that use pleasure craft or locomotives.
SCOS97-NARSTO 1997 SOUTHERN
CALIFORNIA OZONE STUDY AND AEROSOL
STUDY. Principal Investigator: Eric M. Fujita. Desert
Research Institute.
1999. 93-326.
Objectives: To conduct planning
activities for the 1997 Southern California Ozone Study/North American
Research Strategy for Tropospheric Ozone (SCOS97-NARSTO) field study.
Findings: Research objectives
were identified, a work plan developed, costs estimated, co-sponsors
identifying, quality assurance plans and protocols developed, a field
study plan produced, and a field management protocol
delivered. A draft field study plan is available on the Web
at ww.arb.ca.gov/scos/scos.htm.
Importance
to ARB’s Program: The results of the SCOS97-NARSTO study
are needed for a better understanding of the complex meteorological and
chemical processes taking place in the region so that the most
cost-effective route toward attainment of the ozone standards can be
determined. The air pollution control districts in southern
California, the Environmental Protection Agency, the United States
Navy, the North American Research Strategy for Tropospheric Ozone, and
the Coordinating Research Council are co-sponsoring the field study.
CHARACTERIZATION OF OZONE
EPISODES IN THE SOUTH COAST AIR
BASIN: EFFECTS OF AIR PARCEL RESIDENCE TIME AND
WEEKDAY/WEEKEND DIFFERENCES. Principal Investigator:
Warren Blier. University of California, Los Angeles.1996.93-316.
Objectives: To investigate the
effects of residence time and weekday/weekend differences on ozone
levels in the south coast air basin.
Findings: The subregions in
the south coast air basin where control of nitrogen oxides (NOx)
emissions has apparently been most effective are the same subregions
where reductions in the worst ozone episodes have been most
significant. Analyses of the relative benefits of controlling
volatile organic compounds and NOx emissions did not detect a
significant influence of air parcel transport between subregions at
ground level.
Importance
to ARB’s Program: The results helped the ARB determine
that there are differences in weekday and weekend ozone trends.
GUIDANCE FOR USING AIR QUALITY
RELATED INDICATORS IN REPORTING
PROGRESS IN ATTAINING THE STATE AMBIENT AIR QUALITY STANDARDS.
Principal Investigator: Marcella Nystrom. 1993. 93-49.
SIERRA COOPERATIVE OZONE IMPACT
STUDY: YEAR 2 VOLUME 1.
Principal Investigator: John J. Carroll. University of California,
Davis. 1992. A032-129.
POTENTIAL EMISSIONS AND AIR
QUALITY EFFECTS OF ALTERNATIVE
FUELS. Principal Investigator: Thomas C. Austin. Sierra Research Inc.
1989. SR89-03-04.
SOUTHERN CALIFORNIA AIR QUALITY
STUDY: PEROXYACETYL
NITRATE (PAN) MEASUREMENTS. Principal Investigator: Edwin L.
Williams II. Daniel Grosjean and Associates,
Inc. 1989. A6-099-32.
Objectives:
To measure peroxyacetyl
nitrate concentrations during the 1987 Southern California Air Quality
Study. PAN can act as a reservoir of NOx as well as of
oxygenated hydrocarbons, with possible participation in ozone
photochemistry in the latter case.
Findings: Maximum PAN
concentrations measured at ground level and aloft conformed to
expectations. The data indicated spatial and temporal
patterns consistent with current photochemistry concepts. PAN
concentrations measured by another method indicated a 25-30 percent
uncertainty in the measurements.
Importance
to ARB’s Program: These data are useful for assessing the
performance of photochemical air quality modeling efforts.
Modeling is a cornerstone in the determination of future compliance
with the ambient air quality standards.
SOUTHERN CALIFORNIA AIR QUALITY
STUDY: QUALITY ASSURANCE PROGRAM. ENSR Consulting and Engineering.1989.
A6-122-32.
Objectives: To provide quality
assurance for the data collected during the 1987 Southern California
Air Quality Study, and to document the precision, accuracy, and
validity of the data.
Findings: The program
identified a number of problems, and these were subsequently
corrected. Audits performed during the study also uncovered
some problems, most of which were correctable with post-processing of
the data.
Importance
to ARB’s Program: This program illustrated the importance
of a well-designed quality assurance program to the ultimate success of
air pollution field studies.
SUMMARY OF SCAQS UPPER AIR MEASUREMENTS PERFORMED BY THE STI AIRCRAFT. Principal Investigator: J. A. Anderson. Sonoma
Technology, Inc. 1989. A6-098-32.
PERCEPTION OF HYDROGEN SULFIDE
ODOR JIN RELATION TO SETTING
AN AMBIENT STANDARD. Principal Investigator: John E. Amoore, Ph.D.
Olfacto-Labs Berkeley, California. 1985. A4-046-33.
A STUDY OF NITRATE AIR QUALITY
IN THE SOUTH COAST AIR BASIN. Principal Investigator: Glen R. Cass. California Institute of Technology, Pasadena. 1983. A7-169-30.
GEOGRAPHICAL AND TEMPORAL
DISTRIBUTION OF ATMOSPHERIC
MUTAGENS IN CALIFORNIA. Principal Investigator: James N. Pitts, Jr.
University of California, Riverside. 1981. A9-077-31.
MEASUREMENT OF AMBIENT AMMONIA
CONCENTRATIONS IN SOUTHERN CALIFORNIA. Principal Investigator: Matthias Yoong. Rockwell
International. 1981. A7-188-30.
THE EFFECT OF MONO LAKE ON THE
AIR QUALITY IN THE MONO LAKE REGION. Principal Investigator: Bruce H. Kusko. University of
California, Davis.
1981.
A9-147-31.
CHEMICAL CONSEQUENCES OF AIR QUALITY STANDARDS AND OF CONTROL IMPLEMENTATION PROGRAMS.
Principal Investigator: Dr. James N. Pitts, Jr. University of California, Riverside. 1980.
A7-175-30.
GEOGRAPHICAL AND TEMPORAL
DISTRIBUTION OF ATMOSPHERIC MUTAGENS IN CALIFORNIA. Principal Investigator: James N. Pitts, Jr.
University of California, Riverside. 1980. A7-138-30.
METHODS FOR SULFATE AIR QUALITY MANAGEMENT. Principal
Investigator: Glen R. Cass. Institute of Technology Pasadena, CA. 1980.A6-061-87.
Volume II :
Volume III:
AN INTERINDUSTRY ANALYSIS OF
INDUSTRIAL AIR POLLUTANTS FOR THE STATE AND SUBSTATE REGIONS OF CALIFORNIA. Principal
Investigator: Everard M. Lofting. Engineering Economics Associates Berkeley, CA. 1979. A7-143-30.
CHEMICAL CONSEQUENCES OF AIR QUALITY STANDARDS AND OF
CONTROL IMPLEMENTATION. Principal Investigator: Dr. James N. Pitts, Jr.
University of California, Riverside. 1979. A6-172-30.
CORRELATIVE AND SENSITIVE
DISCRIMINANTS FOR AIR QUALITY CONTROL. Principal Investigator: Russell P. Sherwin, M. D. Prof. Staff
Association. 1979.
A6-218-30.
FURTHER INVESTIGATION OF AIR
QUALITY IN THE LAKE TAHOE BASIN. Principal Investigator: John B. Barone. University of
California, Davis. 1979.
A6-219-30.
OBSERVATION PROGRAM FOR AIR POLLUTION MODELS. Principal
Investigator: Peter F. Lester. San Jose State University. 1979. A7-180-30.
EVALUATION OF EMISSION CONTROL
STRATEGIES FOR AIRFIELD OPERATIONS AT THE LOS ANGELES AND SAN FRANCISCO INTERNATIONAL AIRPORTS.
Aerovironment Inc. 1978. A7-077-30.
AIR QUALITY IN THE SOUTH COAST
AIR BASIN: TRENDS, MODELING DATA BASE, AREAL DISTRIBUTION. South Coast Air Quality Management
District. 1977.
A6-164-70.
IMPACT OF INDUSTRIALIZATION OF
THE CALIFORNIA DELTA REGION ON AIR QUALITY. Principal Investigator: D. B. Gemmill. Rockwell
International. 1977.
A6-063-87.
SOURCES OF VISIBILITY
DEGREDATION IN THE LAKE TAHOE AIR BASIN. Principal Investigator: Thomas A. Cahill. University of
California, Davis. 1977. A-5-005-87.
Air Quality Study
CHEMISTRY AND TRANSPORT OF
NITROGEN OXIDES ON THE WESTERN
SLOPES OF THE SIERRA NEVADA MOUNTAINS: IMPLICATIONS FOR LAKE TAHOE.
Principal Investigator: Ronald C. Cohen. University
of California, Berkeley. 2005. 02-331
QUANTIFYING ATMOSPHERIC NITROGEN OXIDES UPWIND AND IN THE
LAKE TAHOE BASIN. Principal Investigator: Ronald C. Cohen. University
of California, Berkeley. 2005. 01-327
QUALITY ASSURANCE ANALYSIS OF
FILTER SAMPLES COLLECTED DURING
THE LAKE TAHOE ATMOSPHERIC DEPOSITION STUDY USING SYNCHROTRON X-RAY
FLUORESCENCE. Principal Investigator: Steven
S. Cliff. University of California, Davis. 2005. 03-344.
SAMPLING AND ANALYSIS FOR THE
LAKE TAHOE ATMOSPHERIC DEPOSITION
STUDY. Principal Investigator:Judith Chow. Desert Research Institute. 2005. 01-351
DRI LAKE TAHOE SOURCE
CHARACTERIZATION STUDY. Principal
Investigator: Hampden Kuhns. Desert Research Institute. 2004. 01-734
IMPROVEMENT OF THE PM EMISSION
INVENTORY FOR THE LAKE TAHOE
REGION. Principal Investigator: Dennis Fitz. University of California,
Riverside. 2004. 01-733
RADAR WIND PROFILER SUPPORT FOR
CALIFORNIA AIR RESOURCES
BOARD LAKE TAHOE ATMOSPHERIC DEPOSITION STUDIES: 2002-2003. Principal
Investigator: Clark W. King. National Oceanic
and Atmospheric Administration. 2003. 01-342
MEASUREMENT OF NITROGENOUS
SPECIES AND SOLAR INTENSITY DURING
THE 1997 SCOS. Principal Investigator: Dennis R. Fitz. University of
California, Riverside. 2000. 96-540
ANALYSIS OF THE SOUTHERN
CALIFORNIA WIND PROFILER AND AIRCRAFT
DATA. Principal Investigator: Sharon G. Douglas. Systems Applications
International, CA. 1997. 94-317
AUDIT OF RADAR WIND PROFILER
NETWORK AND SELECTED SURFACE
METEOROLOGICAL SITES FOR THE 1997 SOUTHERN CALIFORNIA OZONE STUDY. ATC
Associates Inc. 1999. 96-320
SURFACE AND UPPER-AIR VOC
SAMPLING AND ANALYSIS DURING THE
1997 SOUTHERN CALIFORNIA OZONE STUDY. Principal Investigator: Dennis Fitz. University of California, Riverside.
1999. 96-322.
DATA MANAGEMENT UPPER AIR
METEOROLOGICAL NETWORK FOR THE
1997 SOUTHERN CALIFORNIA OZONE STUDY. Principal Investigator: Daniel E.
Wolfe. Environmental Technology Laboratory.
1998. 96-323
ENHANCEMENT OF THE EXISTING
RADAR WIND PROFILER NETWORK
FOR THE 1997 SOUTHERN CALIFORNIA OZONE STUDY. 96-318
SOUTHERN CALIFORNIA AIR QUALITY
STUDY: B-SITE OPERATIONS. Principal
Investigator: Michael Chan. AeroVironment, Inc.1989. A5-196-32.
Objectives: To collect a variety
of air quality data at several sites on the intensive sampling days
during the 1987 Southern California Air Quality Study to support
specialized measurements made by other researchers.
Findings: All data were
collected according to the contract.
Importance
to ARB’s Program: These routine and specialized data on
the intensive study days have been used by other researchers to
understand the air quality problem better and to evaluate the
performance of air quality models.
THE ORIGIN AND FATE OF AIRBORNE POLLUTANTS WITHIN THE SAN JOAQUIN VALLEY. Principal Investigator: T. B.
Smith. California Institute of Technology.
1981.
A7-165-30& A7-171-30
Volume 1:
Volume 2:
Volume 3:
Volume 4:
Volume 5:
THE EFFECTS OF PRESENT AND
POTENTIAL AIR POLLUTION ON IMPORTANT SAN JOAQUIN VALLEY CROPS: SUGAR BEETS. Principal Investigator: Robert F. Brewer. University of California, Parlier. 1978.A6-161-30.
LOS ANGELES TO SAN DIEGO THREE
DIMENSIONAL OZONE TRANSPORT
STUDY. Principal Investigator: Erwin K. Kauper. Metro Monitoring
Services. 1977. A6-090-30.
Volume 2:
FORECASTING OF POLLUTANT
DOSAGES: A STUDY BY LOS ANGELES
COUNTY AIR POLLUTION CONTROL DISTRICT FOR CARB. Principal Investigator:
Eugene L. Fisher. Los Angeles County Air
Pollution Control District. 1973. ARB-1112.
Air Quality/SCAQS
CHARACTERIZATION OF AIR QUALITY DATA FOR THE SOUTHERN
CALIFORNIA AIR QUALITY STUDY. Principal Investigator: Ken Underwood.
Aerovironment, Inc.1995. A932-079.
Objectives:
To
identify precursor sources and formation rates of atmospheric acidity,
using data collected during the 1987 Southern California Air Quality
Study.
Findings:
A
number of findings important to understanding atmospheric acidity
resulted from this contract. First, formic, acetic, and total organic
acid emissions were estimated for the SoCAB at 6,500, 9,000, and
19,700 kilograms/day, respectively. The ozone olefin reaction
was estimated to be a major source of organic acids. Dry deposition far
exceeded removal by rain, accounting for 95 percent of formic
acid removal and 91 percent of acetic acid removal. Overall,
dry deposition accounted for 14 times the deposition by wet
processes in the SoCAB. Second, when aerosol droplets that are
individually in Henry's Law equilibrium with the surrounding air were
mixed together, the resulting bulk mixture was always
supersaturated with weak acids and bases. Third, trajectory analysis
suggested that high sulfate concentrations are associated with air
parcels that passed through a fog layer the previous night. Finally,
multivariate receptor analysis indicated that the atmospheric transport
of gaseous precursors, and their conversion into particulate-phase
acidic species, tended to decouple them from the variations observed in
primary particles co-emitted with the gaseous precursors. Major sources
of acidic compounds were found along the coast in these analyses.
Importance
to ARB’s Program: The results of this project
will help guide the Board in setting atmospheric acidity
and/or deposition standards, should they become necessary.
SIZE TIME COMPOSITIONAL
ANALYSES OF AEROSOLS DURING SCAQS.
Principal Investigator: Thomas A. Cahill. University of California,
Davis. 1990. A732-074.
SOUTHERN CALIFORNIA AIR QUALITY
STUDY. Principal Investigator: R. A. Rasmussen. Biospherics Research Corporation. 1990. A6-179-32.
ORGANIC AND ELEMENTAL CARBON
SIZE DISTRIBUTIONS OF LOS ANGELES AEROSOLS MEASURED DURING SCAQS. Principal Investigator: Peter H. McMurry. University of Minnesota, Minneapolis.
1989. A732-075.
SOUTHERN CALIFORNIA AIR QUALITY
STUDY (SCAQS): DESCRIPTION
OF MEASUREMENT ACTIVITIES. Principal Investigator: S. V.
Hering. Sonoma Technology, Inc.1989.
A5-157-32.
Objectives: To create a reference document
providing an overview of the entire 1987 Southern California Air
Quality Study.
Findings: The reference
document was created.
Importance
to ARB’s Program: This document is a valuable reference for those
interested in using the data collected during the $12 million
study. Academics and researchers engaged in atmospheric
chemistry, other states' air pollution agencies, the U.S. EPA, and
various other research agencies have used this document and its
associated database to reshape clean air management policy.
SOUTHERN CALIFORNIA AIR QUALITY
STUDY: IN-SITU MEASUREMENT
OF AEROSOL ORGANIC AND ELEMENTAL CARBON. Oregon Graduate Center. 1989. A732-072.
Objectives: To make organic and
elemental carbon measurements to provide time-resolved information on
the diurnal variation in the concentrations of carbon
aerosols. Carbon is a major component of the aerosol burden
in the Los Angeles area.
Findings: Both organic and elemental
carbon exhibited large diurnal variations. The limited amount
of data indicate that the carbon aerosol burden is higher in the fall
than in the summer. The origin of the carbon appears to be
directly emitted (primary) during the fall; during the summer, primary
carbon was dominant on some days and photochemically produced carbon
(secondary) was dominant on other days.
Importance
to ARB’s Program: This study provided additional insight
into the nature of carbon aerosol and will be useful for further
research and the design of future studies and control policies.
SOUTHERN CALIFORNIA AIR QUALITY
STUDY - FALL STUDY. Principal
Investigator: B. R. Appel. California Department Health Services,
Berkeley. 1988.
A732-089.
THE SOUTHERN CALIFORNIA AIR
QUALITY STUDY: TUNABLE DIODE
LASER ABSORPTION SPECTROMETER MEASUREMENTS OF H2O2 AND H2CO AT THE
CLAREMONT AND LONG BEACH "A" SITES.
Principal Investigator: G. I. Mackay. Unisearch Associates Inc. 1988. A732-073.
Atmospheric
Processes
HOW NEW CHEMISTRY FINDINGS AFFECT OUR UNDERSTANDING OF THE WEEKEND EFFECT A MODELING STUDY. Principal Investigator: Donald Dabdub, Ph.D. University of California, Irvine. 2008. 04-333
DEVELOPMENT AND DEMONSTRATION
OF AN AEROSOL TRACER TECHNIQUE BASED ON NEUTRON ACTIVATION ANALYSIS FOR
STUDYING CYCLICAL DEPOSITION AND RESUSPENSION OF AEROSOLS FROM
SURFACES. Principal Investigator: Keith D. Stolzenbach and Arthur M. Winer, Ph.D. University of California, Los Angeles. 2008. 04-345
DEVELOPMENT OF DATABASE FOR
HUMAN EXPOSURE TO AIR POLLUTION
IN THE SOUTH COAST AIR BASIN. Principal Investigator: Yuji Horie.
Technology Service Inc. 1979. A7-163-30.
Biogenic
DEVELOPMENT AND VALIDATION OF
DATABASES FOR MODELING BIOGENIC
HYDROCARBONS IN CALIFORNIA’S AIRSHEDS. Principal
Investigator: Arthur M. Winer, Ph.D. University of
California,
Los Angeles.
2001. 97-320.
Objective: The objective of this project
is to produce gridded, speciated, day-specific biogenic hydrocarbon
(BHC) inventories for the entire state of California.
Investigators will: (1) use a photoionization detection system to
measure total hydrocarbon emissions from at least 300
never-before-sampled California plant species, identifying both
emitters and non-emitters; (2) develop and test taxonomic and
structural class methodologies for estimating leaf biomass constants;
(3) conduct leaf biomass sampling among high-emitting oak species in
rangeland environments and develop statistically robust data on leaf
biomass per volume ratios; and (4) conduct a quantitative, field-based
analysis of the “gaps in the United States ecological inventory” (GAP)
geographic information system (GIS) land cover vegetation database for
the San Joaquin Valley.
Importance
to ARB’s Program: In those California airsheds where the land is
mostly covered by vegetation, accurate BHC inventories are critical for
determining the proper mix of hydrocarbon and nitrogen oxides emissions
control strategies. Legislative mandates also require that
emissions inventories, which are used as tools for air pollution
decision-makers, be as accurate and complete as the state of the
science permits. The databases and maps resulting from this study will
help ARB staff to develop accurate and reliable biogenic hydrocarbon
emissions simulation. Project investigators will work
collaboratively with ARB staff to further develop these data and
methodologies into a state-of-the-science statewide BHC emissions
inventory for California.
WHOLE ECOSYSTEM MEASUREMENTS OF
BIOGENIC HYDROCARBON EMISSIONS.
Principal Investigator: Dr. Allen H. Goldstein. University of
California, Berkeley. 2001. 98-328.
BIOGENIC HYDROCARBON
INVENTORIES FOR CALIFORNIA: GENERATION
OF ESSENTIAL DATABASES. Principal Investigator:
Arthur M. Winer. University of California, Los Angeles.
1998.
95-309.
Objectives: To generate the
databases essential to building a biogenic hydrocarbon emissions
inventory for California. Also, to evaluate existing
taxonomic models and databases.
Findings: Investigators for
this study expanded and refined the University of California, Los
Angeles taxonomic model for estimating isoprene emissions rates for
plant species where no experimental measurements are
available. They doubled the number of high-emitting plant
species measured for isoprene emissions rates under realistic field
conditions and measured dry leaf biomass per volume, including whole
tree leaf mass, for plant species which represent the most critical
gaps in biomass estimation for key air basins, such as the San Joaquin
Valley. Investigators also evaluated the Gap Analysis Project
(GAP) database, determining uncertainties and limitations of the
system, and developed recommendations for utilizing this Geographic
Information System (GIS) database for development of biogenic
hydrocarbon emissions inventories. Ambient air measurements
of biogenic hydrocarbons were collected during the Southern California
Ozone Study (SCOS97-NARSTO). The resulting data will be
incorporated into the resulting SCOS97-NARSTO databases.
Finally, the UCLA staff advised the ARB on the development of the
Biogenic Emission Inventory through Geographic Information Systems
(BEIGIS) modeling program, and the information available through its
expanded databases.
Importance
to ARB’s Program: Control options for vegetation and,
therefore, biogenic emissions are limited. The results of
this study will improve the ARB’s ability to estimate these emissions
and determine the contribution of biogenic vs. anthropogenic
sources. Data from this project will also help evaluate the
emphasis of future ozone control strategies regarding nitrogen oxides
and hydrocarbons.
CRITICAL EVALUATION OF A
BIOGENIC EMISSION SYSTEM FOR PHOTOCHEMICAL GRID MODELING IN CALIFORNIA. Principal Investigator: Arthur M. Winer.
University of California, Los Angeles. 1995. 93-725.
DETERMINATION OF
VARIABILITY IN LEAF BIOMASS DENSITIES OF
CONIFERS AND MIXED CONIFERS UNDER DIFFERENT ENVIRONMENTAL CONDITIONS IN
CALIFORNIA'S SAN JOAQUIN VALLEY AIR BASIN. Principal
Investigator: Patrick J. Temple. University of California, Riverside. 1995. 92-303.
Objectives: To update the ARB's
San Joaquin Valley Air Basin emissions inventory to include emission of
organic gases from conifer forests on the western slopes of the Sierra
Nevada.
Findings: This field study
produced a wealth of raw data on foliar biomass estimates and
environmental conditions. Elevation was found to be the most
useful parameter for predicting foliar biomass of conifer-dominated
plots. The relation between biomass of conifer-dominated
plots and elevation was used to construct a GIS-based map and lookup
table of the distribution of conifer foliar biomass for 2 x 2 km grid
cells across elevational gradients in the area studied. Oak
biomass displayed low variability across plots. The best
predictor of oak foliar biomass may be the mean biomass of the plots
studied.
Importance
to ARB’s Program: The ARB and other entities used the
results of this project, along with emission factors obtained by other
investigators, to estimate biogenic hydrocarbon emissions.
This information will be employed in the production of a good emissions
inventory (for the two major vegetation types found in this valley) for
use in Clean Air Act implementation plans.
HYDROCARBON EMISSIONS FROM
VEGETATION FOUND IN CALIFORNIA'S
CENTRAL VALLEY. Principal Investigator: Arthur M. Winer.
University of California, Riverside. Research
Note 90-12. 1989. A732-155.
Objectives: To determine the
emission rates and chemical composition of organic gases emitted by
prominent vegetative species in California's central valley.
The new data fill a critical gap in the reactive organic gases
emissions inventory.
Findings: Hydrocarbon
compounds emitted by more than 30 of the most common agricultural and
natural plants found in California's Central Valley were separated and
measured. All of the plant species tested emitted some of
these hydrocarbons at rates suggesting a possible effect upon air
quality.
Importance
to ARB’s Program: These data together with data on land
use and biomass density were employed by ARB staff to develop a
hydrocarbon emissions inventory for agriculturally important and
naturally occurring vegetation sources. This places biogenic
sources in perspective for development of ozone attainment plans for
the Clean Air Act.
INVESTIGATION OF THE ROLE OF
NATURAL HYDROCARBONS IN
PHOTOCHEMICAL SMOG FORMATION IN CALIFORNIA. Principal Investigator: Dr.
Arthur M. Winer. University of California,
Riverside. 1983. A0-056-32.
Chemistry
NIGHTTIME CHEMISTRY:
OBSERVATIONS OF NO3 AND N2O5. Principal Investigator:Ronald C. Cohen. University of California,
Berkeley. 2008. 04-335
IDENTIFICATION AND ATMOSPHERIC
REACTIONS OF POLAR PRODUCTS
OF SELECTED AROMATIC HYDROCARBONS. Principal Investigator: Roger
Atkinson & Janet Arey. University of California,
Riverside. 2006. 03-319
EVALUATION OF ATMOSPHERIC
IMPACTS OF SELECTED COATINGS VOC EMISSIONS. Principal Investigator: William P. L.Carter. University of
California, Riverside. 2005. 00-333.
GAS-PHASE FORMATION RATES ON
NITRIC ACID AND ITS ISOMERS
UNDER URBAN CONDITIONS. Principal Investigator: Mitchio Okumura.
California Institute of Technology. 2005. 03-333
DEVELOPMENT AND EVALUATION
OF A GAS-PHASE ATMOSPHERIC REACTION MECHANISM FOR LOW NOX CONDITIONS.
Principal Investigator: William P. L.Carter.
University of California, Riverside. 2004. 01-305
HETEROGENEOUS NOX CHEMISTRY IN
POLLUTED URBAN ATMOSPHERES: IMPLICATIONS FOR THE FORMATION OF PARTICLES AND OZONE AND CONTROL
STRATEGY DEVELOPMENT. Principal Investigator: Barbara
J. Finlayson-Pitts. University of California, Irvine. 2004. 00-323
A CRITICAL REVIEW OF THE
PARTICULATE MATTER TOXICOLOGY LITERATURE
FOR SENATE BILL 25 REVIEW OF THE PARTICULATE MATTER STANDARD. Principal
Investigator: Kent E. Pinkerton, Ph.D.
University of California, Davis. 2002.
00-327.
LINKAGES BETWEEN MEASUREMENTS
OF MULTIFUNCTIONAL AND POLAR
ORGANICS IN CHAMBER STUDIES AND THE AMBIENT ENVIRONMENT. Principal
Investigator: M. Judith Charles. University
of California, Davis. 2002. 98-311.
ATMOSPHERIC CHEMISTRY OF
SELECTED LINEAR, BRANCHED AND CYCLIC
C10 ALKANE COMPONENTS OF MINERAL SPIRITS. Principal Investigator: Roger
Atkinson. University of California, Riverside.
2001. 97-312.
THE FORMATION OF GASEOUS
NITROUS ACID (HONO): A KEY DETERMINANT
OF TROPOSPHERIC OZONE AND FINE PARTICLES. Principal Investigator:
Barbara J. Finlayson-Pitts University of California,
Irvine. 2001. 97-311
YIELDS AND REACTIONS OF
INTERMEDIATE COMPOUNDS FORMED FROM
THE INITIAL ATMOSPHERIC REACTIONS OF SELECTED VOCS. Principal
Investigator: Roger Atkinson. University of California,
Riverside. 2001. 96-306.
THE IDENTITIES AND BEHAVIOR OF
MULTI-FUNCTIONAL CARBONYLS IN SIMULATED AND AMBIENT ATMOSPHERIC
ENVIRONMENTS. Principal Investigator: M.Judith Charles. University of
California, Davis. 1999. 96-303.
ENVIRONMENTAL CHAMBER STUDIES
FOR DEVELOPMENT OF AN UPDATED
PHOTOCHEMICAL MECHANISM FOR VOC REACTIVITY ASSESSMENT.
Principal Investigator: William P. L. Carter. University
of California, Riverside.1997. 92-345.
Objectives: To provide
experimental data for another ARB-funded project (92-329, below) to
update the maximum incremental reactivity (MIR) scale used in
calculating reactivity adjustment factors (RAFs) for the Low-Emission
Vehicles/Clean Fuels (LEV/CF) regulations. "Reactivity"
refers to the tendency of airborne chemicals to form ozone.
The RAFs are used to equalize the stringent hydrocarbon exhaust
emission standards for reformulated gasoline and other alternative
fuels against conventional gasoline in terms of their reactivity.
Findings: MIRs have been
calculated using assumed chemical mechanisms in models. In
this study, (1) a xenon arc light source was used to assess whether
current chemical mechanisms adequately treat the effects of real light
on reactivity; (2) light intensity measurement methods used to
characterize the conditions within the chambers were evaluated; (3) the
effects of humidity on the reproducibility of chamber runs were
assessed; and (4) the environmental chamber database was extended to
include aromatic hydrocarbons (which are usually highly reactive and,
before these experiments, not well characterized).
Importance
to ARB’s Program: The update to the MIR scale is required
by the Board's LEV/CF regulations. In all, 283 environmental
chamber experiments were conducted to provide a comprehensive set of
experiments that can be used to develop and test models' chemical
mechanisms and evaluate the reactivity of hydrocarbons.
PRODUCT STUDIES OF THE
ATMOSPHERICALLY IMPORTANT REACTIONS
OF ALKENES AND AROMATIC HYDROCARBONS. Principal Investigator: Roger
Atkinson. Statewide Air Pollution Research
Center, University of California, Riverside. 1997. 94-311.
Objectives: To determine the
products of the atmospheric reactions of aromatic compounds and to
extend research on ozone-alkene reactions to all the important alkenes
found in the atmosphere.
Findings: The products of
important alkene reactions with ozone and OH were determined.
The reactions studied included the reaction of ozone (in the presence
of OH radical scavenger) with 2-methylpropene, trans-2 butene and
2,3-dimethyl-2-butene, propene, cis-2-butene, and
2-methyl-2-butene. Alkene and OH radical reactions studied
included the reaction of cis-2-butene, 2,3-dimethyl-2-butene,
2-methylpropene, and 2-methyl-2-butene with OH radical (in the presence
of and absence of NOx). Aromatic compound reaction product
studies were also performed. The reactions studied included
the reaction of OH (in the presence of NOx) and NO3 radical reactions
with naphthalene, 1- and 2-methylnaphthalene, acenaphthene,
acenaphthylene, and the OH radical reaction with biphenyl (because
biphenyl has been shown to not react with NO3 radical).
Reaction products included many carbonyl and multifunctional carbonyl
products, as expected.
Importance
to ARB’s Program: About 30 percent of the total reactive
organic gases in urban air consists of aromatic hydrocarbons and
alkenes. Because of their high ozone formation potential,
these compounds are the main precursors of ozone. It is
important to understand their chemistry to ensure that appropriate
control strategies are implemented. The results of this study
will improve the chemical mechanisms used in the reactivity scale for
the Board's Low-Emission Vehicle/Clean Fuel regulations and in the
photochemical airshed models used for development of California's plans
for implementation of Federal emission and air quality requirements for
ozone. Additional funding was provided by the Coordinating
Research Council, a research cooperative supported by the automobile
and oil production industries.
ASSESSMENT OF EFFECTS OF
CHEMICAL MECHANISM UNCERTAINTY
ON AIRSHED MODEL RESULTS. Principal Investigator: Narseh Kumar.
University of California, Riverside. 1996. 93-716.
ENVIRONMENTAL CHAMBER STUDIES
OF ATMOSPHERIC REACTIVITIES
OF VOLATILE ORGANIC COMPOUNDS. EFFECTS OF VARYING CHAMBER AND LIGHT
SOURCE. Principal Investigator: William P.
L. Carter. University of California, Riverside. 1995. A032-069.
CLAREMONT ATMOSPHERIC
FREE-RADICAL STUDY: MEASUREMENTS
OF FORMALDEHYDE, HYDROGEN PEROXIDE, NITRIC ACID, NITROUS ACID,
PEROXYACETYL NITRATE, NITROGEN DIOXIDE, NITROGEN
OXIDES, OZONE, CARBON MONOXIDE, HYDROCARBONS C1-C12, AND CARBONYL
COMPOUNDS C1-BENZALDEHYDE. Unisearch Associates,
Inc. and AtmAA, Inc. 1994. 92-327.
Objectives: To create a
database to enable airshed models to evaluate the free-radical balance
in chemical mechanisms. Radicals initiate ozone production in
the morning and sustain it during the day. Previous
atmospheric measurements had implied that there are uninventoried
sources of formaldehyde, nitrous acid, higher aldehydes, and other
radical precursors, implying that current model applications may
overestimate the effects of hydrocarbon control, leading to
underestimates of NOx control.
Findings: The field study
captured data during a wide range of meteorological conditions and
ozone concentrations, including the highest ozone episode for the year
(over 0.30 ppm).
Importance
to ARB’s Program: The results will be used to evaluate
the airshed models currently used for verification of compliance with
progress in ozone control as noted in the State and Federal plans for
implementation of emissions and air quality standards under the 1991
amendments to the Federal Clean Air Act.
EXPERIMENTAL INVESTIGATION OF
THE ATMOSPHERIC CHEMISTRY
OF AROMATIC HYDROCARBONS AND LONG-CHAIN ALKANES. Principal
Investigator: Roger Atkinson. University of California,
Riverside.1994. A032-067.
Objectives: To study the
reaction sequences of several hydrocarbons under ozone-forming
conditions in environmental chambers. The unique feature of
this study is the vast array of analytical approaches available to the
investigators.
Findings: The investigators
found direct evidence for reactions involving aromatic hydrocarbons and
alkanes. This evidence has bearing on the controversy as to
whether it is non-methane organic gases or nitrogen oxides that control
ozone production in the atmosphere.
Importance
to ARB’s Program: The results were used to update the
chemical mechanism that is part of the airshed models used for
developing California's plans for implementing Federal air quality
requirements, and for performing the update to the maximum incremental
reactivity scale required by the Board's Low-Emission Vehicles and
Clean Fuels regulations.
GAS PHASE ATMOSPHERIC CHEMISTRY
OF ORGANIC COMPOUNDS.
Principal Investigator: Roger Atkinson. University of California,
Riverside. 1988. A5-122-32.
MEASUREMENTS OF NO2, HONO, NO3,
HCHO, PAH, NITROARENES AND PARTICULATE MUTAGENIC ACTIVITIES DURING THE
CARBONACEOUS SPECIES METHODS COMPARISON
STUDY. Principal Investigators: Dr. Roger Atkinson & Dr. Arthur
M. Winer. University of California, Riverside.
1988. A5-150-32.
FORMATION AND CONTROL OF
NITROGEN - CONTAINING AIR POLLUTANTS.
Principal Investigator: Armistead G. Russell. California Institute of
Technology, Pasadena. 1987. A2-150-32.
INVESTIGATION OF THE ROLE OF
NATURAL HYDROCARBONS IN PHOTOCHEMICAL SMOG FORMATION IN CALIFORNIA. Principal Investigator: Dr.
Arthur M. Winer. University of California,
Riverside. 1981. A8-135-31.
CHARACTERIZATION STUDIES OF THE
SELECTIVE REDUCTION OF
NO BY NH 3. Principal Investigator: N. J. Brown. University of
California, Berkeley.
1979. A6-196-30.
CHEMICAL CONSENQUENCES OF AIR
QUALITY STANDARDS AND OF CONTROL
IMPLEMENTATION. PROGRAMS: "ROLES OF HYDROCARBONS, OXIDES OF NITROGEN,
AND AGED SMOG IN THE PRODUCTION OF PHOTOCHEMICAL
OXIDANT." Principal Investigator: James N. Pitts, Jr. University of
California, Riverside. 1973. 2-377.
EXPERIMENTAL DESIGN FOR AEROSOL
CHARACTERIZATION STUDY.
Principal Investigator: G. M. Hidy. University of California,
Riverside. 1972. ARB-358.
Volume IV:
PHOTOCHEMISTRY OF THE GASEOUS
HYDROGEN PEROXIDE - CARBON
MONOXIDE SYSTEM: RATE CONSTANTS FOR HYDROXYL RADICAL REACTIONS BY
COMPETITIVE KINETICS. Principal Investigator:
David H. Volman. University of California, Davis. 1972. 5-143-2 and 023.
Control Strategy
RESEARCH INTO THE DEVELOPMENT OF BIOLOGICAL METHODS OF DUST SUPPRESSION IN THE ANTELOPE VALLEY. Principal Investigator:
Jason Unger. San Diego State University. 2007. 01-339.
AMBIENT CONCENTRATIONS OF
PEROXYACETYL NITRATE (PAN), PEROXYPROFIONYL
NITRATE (PPN) AND PERCHLOROETHYLENE (PCE) IN AZUSA, CA, FEBRUARY
2001--SEPTEMBER 2003. Principal Investigator: Eric Grosjean. DGA, Inc. 2005. 99-703.
AIR MONITORING PROGRAM FOR
DETERMINATION OF THE IMPACTS OF INTRODUCTION OF CALIFORNIA'S PHASE 2 REFORMULATED GASOLINE ON AIR QUALITY IN THE SoCAB. Principal Investigator:
Barbara Zielinska. Desert Research Institute. 1999. 94-332.
Objectives: To collect and
validate samples of ambient volatile organic compounds (VOCs) and
carbonyl from the South Coast Air Basin (SoCAB) during the summers of
1995 and 1996, and from areas in southern California and Mexico during
the summer of 1997. Also, to collect and analyze samples
representative of cold start, hot stabilized, and evaporative emissions
from motor vehicles, and headspace of liquid gasoline.
Findings: The study provided
a data set of VOC and carbonyl emissions for the southern portion of
the State, as they relate to the impacts on ambient air concentrations
of hydrocarbon species as a result of the introduction of California’s
Cleaner Burning Gasoline (CBG). Ambient air sampling was
performed at four sites in the SoCAB before the introduction of CBG
(1995) and after (1996). Additional sampling occurred during
the summer of 1997, in conjunction with the 1997 Southern California
Ozone Study (SCOS97-NARSTO).
Importance
to ARB’s Program: The results of this study will be used
to identify and quantify the changes in ambient concentrations of
specific hydrocarbons related to the introduction of CBG. It
will also provide the data necessary for ARB to evaluate the impact of
this regulatory program on atmospheric levels of ozone precursors and
toxic air contaminants. Additionally, this data, in
conjunction with data from SCOS97-NARSTO, will be used to improve
models used to design air quality control plans and strategies for
California.
AIR QUALITY MITIGATION MEASURES
FOR AIRPORTS. Energy &
Environmental Analysis, Inc. 1994.A132-168.
Objectives: To identify and
quantify the effectiveness of air quality mitigation measures designed
to minimize emissions of hydrocarbons, carbon monoxide, nitrogen
oxides, and particulate matter generated by all aspects of airport
activity, especially construction and expansion.
Findings: This study produced
a draft list of air quality mitigation measures designed to minimize
emissions generated by aircraft ground and flight operations, and land
use developments associated with the construction of airports.
Importance
to ARB’s Program: The ARB is the State agency responsible
for certifying under the Airport and Airway Safety and Capacity
Expansion Act of 1987 that airport projects will comply with applicable
air quality standards. With the information from this study,
we are better able to evaluate airport projects to minimize the impact
of emissions.
CONTROL OF ATMOSPHERIC FINE PRIMARY CARBON PARTICLE CONCENTRATIONS.
Principal Investigator: Glen R. Cass. Institute of Technology Pasadena,
CA. 1986. A1-071-32
EFFECTS OF METHANOL FUEL
SUBSTITUTION ON MULTI-DAY AIR
POLLUTION EPISODES. Principal Investigator: William P. L. Carter.
University of California, Riverside. 1986. A3-125-32.
CHEMICAL CONSEQUENCES OF AIR
QUALITY STANDARDS AND CONTROL
IMPLEMENTATION PROGRAMS. Principal Investigator: James N. Pitts, Jr.
University of California, Riverside. 1983. A1-030-32.
CHEMICAL CONSEQUENCES OF AIR
QUALITY STANDARDS AND OF
CONTROL IMPLEMENTATION PROGRAMS. Principal Investigator: Dr. James N.
Pitts, Jr. University of California, Riverside.
1981. A8-145-31.
CHEMICAL CONSEQUENCES OF AIR
QUALITY STANDARDS AND OF CONTROL
IMPLEMENTATION PROGRAMS: ROLES OF HYDROCARBONS, OXIDES OF NITROGEN,
OXIDES OF SULFUR AND AGED SMOG IN THE PRODUCTION
OF PHOTOCHEMICAL OXIDANT AND AEROSOL. Principal Investigator: Dr. James
N. Pitts, Jr. University of California,
Riverside. 1977. 5-385.
TECHNICAL BASES FOR CONTROL
STRATEGIES OF PHOTOCHEMICAL OXIDANT:
CURRENT STATUS AND PRIORITIES IN RESEARCH. Principal Investigator:
James N. Pitts, Jr. University of Riverside,
CA. 1976. 3-974.
EVALUATION OF A SHORT TERM
OXIDANT CONTROL STRATEGY. Principal Investigator: Kent R. Wilson. University of California, San
Diego. 1976. ARB-4-718.
CHEMICAL CONSEQUENCES OF AIR
QUALITY STANDARDS AND OF CONTROL IMPLEMENTATION PROGRAMS: ROLES OF HYDROCARBONS, OXIDES OF NITROGEN AND
AGED SMOG IN THE PRODUCTION OF PHOTOCHEMICAL OXIDANT. Principal Investigator: Dr. James N. Pitts, Jr. University of
California, Riverside. 1975. 3-017.
Data Analysis
SPATIAL AND TEMPORAL
CHARACTERIZATION OF FINE PARTICULATE
MATTER MASS CONCENTRATIONS IN CALIFORNIA, 1980-2002. Envair,
CA.2005. 03-350.
OZONE AND PARTICULATE MATTER
CASE STUDY ANALYSES FOR THE
SOUTHERN CALIFORNIA AIR QUALITY STUDY. Sonoma Technology, Inc. 1993. A932-050.
Objectives: To investigate the
three-dimensional evolution of two ozone episodes and three PM10
episodes during the 1987 Southern California Air Quality Study,
including the transport and transformation processes that lead to
maximum pollutant concentrations in the south coast air basin.
Findings: The most
significant finding of the study is that airshed model predictions of
ozone aloft do not agree well with the observed concentrations and
structure.
Importance
to ARB’s Program: These results imply that current
airshed modeling efforts may be missing an important upper air
recirculation pattern, and research efforts are being undertaken to
improve our understanding of this pattern. Recirculation
patterns have important implications for photochemical modeling used to
evaluate strategies to meet the ambient air quality standards as
required by the California and Federal Clean Air Acts.
ANALYSIS OF AMBIENT VOC DATA
COLLECTED IN THE SOUTHERN
CALIFORNIA AIR QUALITY STUDY. Principal Investigator:
Frederick W. Lurmann. Sonoma Technology, Inc. 1992. A832-130.
Objectives: To analyze the
behavior of nonmethane organic gases (NMOG) in the south coast air
basin using data collected during the 1987 Southern California Air
Quality Study (SCAQS). NMOG are of concern because of their
role in the formation of ozone.
Findings: NMOG composition
and NMOG/NOx ratios were similar throughout the basin.
Ambient NMOG composition resembled that of motor vehicle exhaust,
suggesting that the dominant source is most likely motor
vehicles. The early morning ambient NMOG/NOx and CO/NOx
ratios and profiles were inconsistent with those of the emissions
inventory, indicating that CO and NMOG emissions from motor vehicles
are underestimated in the inventory. There appear to be large
amounts of carbonyl compounds (ozone precursors) formed in the urban
atmosphere from photo-oxidation of hydrocarbons.
Importance
to ARB’s Program: This study contributed to new insights
into the deficiencies of our emissions inventory, to the understanding
of the widespread and continuous contribution of motor vehicle
emissions to urban air pollution, and to the important contribution of
carbonyls to the chemistry of air pollution.
CARBONACEOUS SPECIES METHODS
COMPARISON STUDY, INTERLABORATORY
ROUND ROBIN: INTERPRETATION OF RESULTS. G2
Environmental. 1990. A832-154.
Objectives: To conduct a 13-member
interlaboratory comparison for measurements of total carbon (TC),
organic carbon (OC), and elemental carbon (EC), major constituents of
ambient particulate matter. Interlaboratory measurement
differences for OC and EC are typically quite large, and the object of
this study was to determine the magnitude of the differences and the
reasons for this variation.
Findings: The interlaboratory
variations were attributed to several different causes. These
results indicate where modifications in the analytical process need to
be made.
Importance
to ARB’s Program: The resulting improvement in ambient particulate
matter measurement accuracy is a necessary step toward attainment of
the ambient air quality standards for PM10.
ESTIMATING MEAN CONCENTRATIONS
WHEN SOME DATA ARE BELOW
THE DETECTION LIMIT. Principal Investigator: R | 
