6,992 research outputs found
Ground Water Quality Effects on Domestic Water Utilization
The work upon which this report is based was supported in part by
funds (Project A-040-ALAS) provided by the United States Department of
the Interior, Office of Water Resources Research, as authorized under
the Water Resources Act of 1964, as amended
An Angular Correlation Test of Time Reversal Invariance
Gamma-ray angular correlation experiment of time reversal invarianc
A Survey of Lentic Waters with Respect to Dissolved and Particulate Lead
Some of the strongest temperature inversions in the world occur at
Fairbanks, Alaska. Benson (1970) has reported that a temperature gradient
of 10 to 30C/1OO m is common in the winter inversions that form at
Fairbanks. Air pollution is especially severe during these inversions
when it is accompanied by the formation of ice crystals in the air, a
condition known as ice fog. This phenomenon occurs when the temperature
drops below -20F (-35C) (Benson, 1970), and it intensifies with time if
the inversion is not broken.
The ice crystals in this fog have been found to adsorb dust and gasses,
including the lead halides which are present in the air as a result of the
combustion of tetraethyl lead and/or other lead-hydrocarbon compounds used
as anti-knock additives in automotive gasoline. Lazrus et al. (1970) have
found lead concentrations in precipitation to be highly significantly correlated
with the amount of gasoline used in the area sampled.
There are two factors that bring the concentration of lead to high
levels in ice fogs. Evaporation of the ice crystals tends to concentrate
pollutants in the air mass, especially over the core area of the city
where precipitation is retarded by the heating effect of the city. Also,
during the extreme cold weather accompanying this phenomenon, many people
allow their cars to idle when they are parked to increase performance and
for reasons of personal comfort.
Eventually, much of the pollutants suspended in the ice fog is precipitated and causes unnaturally high levels of lead in the snow. (Winchester et al., 1967). It is suspected that some of this particulate
lead collected in the snow may be carried along with the associated surface
runoff into 1entic (standing) surface waters during thawing. The
objectives of this project were:
1. to measure the amount of dissolved and particulate lead in a
number of selected 1entic waters in the Fairbanks area, and
2. to measure the amount of lead that has been incorporated into net plankton organisms located in the selected lentic waters.The work upon which this report is based was supported by funds (Project A-035-ALAS) provided by the United States Department of the Interior, Office of Water Resources Research, as authorized under the
Water Resources Act of 1964, as amended
A deep Chandra observation of Abell 4059: a new face to radio-mode AGN feedback?
A deep Chandra observation of the cooling core cluster Abell 4059 (A4059) is
presented. Previous studies have found two X-ray cavities in the central
regions of A4059 together with a ridge of X-ray emission 20kpc south-west of
the cluster center. These features are clearly related to the radio galaxy
PKS2354-35 which resides in the cD galaxy. Our new data confirm these previous
findings and strengthen previous suggestions that the south-western ridge is
colder and denser than, but in approximate pressure equilibrium with, the
surrounding ICM atmosphere. In addition, we find evidence for a weak shock that
wraps around the north and east sides of the cavity structure. Our data allow
us to map the 2-dimensional distribution of metals in the ICM of A4059 for the
first time. We find that the SW ridge possesses an anomalously high
(super-solar) metalicity. The unusual morphology, temperature structure and
metal distribution all point to significant asymmetry in the ICM atmosphere
prior to the onset of radio-galaxy activity. Motivated by the very high
metalicity of the SW ridge, we hypothesize that the ICM asymmetry was caused by
the extremely rapid stripping of metal enriched gas from a starburst galaxy
that plunged through the core of A4059. Furthermore, we suggest that the onset
of powerful radio-galaxy activity in the cD galaxy may have been initiated by
this starburst/stripping event, either via the tidal-shocking of cold gas
native to the cD galaxy, or the accretion of cold gas that had been stripped
from the starburst galaxy.Comment: Accepted for publication in the Astrophysical Journal. 12 pages, 11
figures. A version of this paper including full resolution figures can be
found at http://www.astro.umd.edu/~chris/publications/papers/a4059_2008.pd
Nutrient chemistry of a large, deep lake in subarctic Alaska
Project Officer
Eldor W. Schallock
Assessment and Criteria Development Division
Corvallis Environmental Research Laboratory
Corvallis, Oregon 97330;Corvallis Environmental Research Laboratory
Office of Research and Development
U. S. Environmental Protection Agency
Corvallis, Oregon 97330; R800276The primary objective of this project was to assess the state of the
water quality of Harding Lake, and to attempt to predict the effects of
future development within its watershed. Since the major effect of degradation
of water quality due to human activity is the promotion of nuisance
growths of plants, the major emphasis was placed on measurements of plant
growth and concentrations of the major nutrients they require. Planktonic
algal growth was found to be low, below 95.6 gm/m2/year, and the growth of
submerged rooted plants was found to be relatively less important at approximately
1.35 gm/m2/year. Measurements of the growth of attached algae were
not conducted, therefore the relative importance of their growth is currently
unknown.
A model for predicting the effect of future real estate development in
the watershed was modified and applied to this lake. This model adequately
describes current water quality conditions, and is assumed to have some
predictive ability, but several cautions concerning application of this
model to Harding Lake are discussed.
A secondary objective was to study the thermal regime of a deep subarctic
lake. Intensive water temperature measurements were made throughout
one year and less intensive measurements were conducted during two additional
years. The possibility that this lake may occasionally stratify thermally
under the ice and not mix completely in the spring was discovered. The
implications of this possibility are discussed for management of subarctic
lakes. Hydrologic and energy budgets of this lake are attempted; the annual
heat budget is estimated at 1.96 x 104 ± 1.7 x 103 cal/cm2.
The results of a study of domestic water supply and waste disposal
alternatives in the watershed, and the potential for enteric bacterial contamination
of the lake water are presented. Limited work on the zooplankton,
fishes, and benthic macroinvertebrates of this lake is also presented
Angular Correlation of Cascade Gamma Rays in 94nb
Angular correlation of cascade gamma rays in niobiu
Addressing Religion and Spirituality in Psychotherapy: Clients\u27 Perspectives
Twelve adult clients described the role of religion and spirituality in their lives and in therapy as a whole, as well as their specific experiences of discussing religious-spiritual topics in individual outpatient psychotherapy with nonreligiously affiliated therapists. Data were analyzed using Consensual Qualitative Research (CQR; Hill, Thompson, & Williams, 1997). Results indicated that clients were regularly involved in religious-spiritual activities, usually did not know the religious-spiritual orientation of their therapists, but often found them open to such discussions. Specific helpful discussions of religion-spirituality were often begun by clients in the 1st year of therapy, were related to clients\u27 presenting concerns, were facilitated by therapists\u27 openness, and yielded positive effects. Specific unhelpful discussions were raised equally by clients and therapists early in therapy, made clients feel judged, and evoked negative effects. Implications for practice and research are addressed
Timesharing performance as an indicator of pilot mental workload
Attentional deficits (workloads) were evaluated in a timesharing task. The results from this and other experiments were incorporated into an expert system designed to provide workload metric selection advice to non-experts in the field interested in operator workload
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