72,187 research outputs found
Death, Disease, and Dirty Power: Mortality and Health Damage Due to Air Pollution From Power Plants
Summarizes the findings of a study that looks at the contribution of air emissions from power plants to fine particle levels, and the impact of those emissions on human health. Discusses policies that would reduce power plant fine particle pollution
Decoherence and fidelity in ion traps with fluctuating trap parameters
We consider two different kinds of fluctuations in an ion trap potential:
external fluctuating electrical fields, which cause statistical movement
(``wobbling'') of the ion relative to the center of the trap, and fluctuations
of the spring constant, which are due to fluctuations of the ac-component of
the potential applied in the Paul trap for ions. We write down master equations
for both cases and, averaging out the noise, obtain expressions for the heating
of the ion. We compare our results to previous results for far-off resonance
optical traps and heating in ion traps. The effect of fluctuating external
electrical fields for a quantum gate operation (controlled-NOT) is determined
and the fidelity for that operation derived.Comment: 11 pages, 4 figure
Photochemical Degradation of Malathion
Completion Report
OWRT Agreement No. 14-34-0001-6002
Project No. A-057-ALASThis is the final completion report for a two-year project which
began 1 November 1975. The original completion date was extended to 30
September 1977 to allow collection of samples and data through the
summer of 1977.
Malathion is a thiophosphate insecticide, 0,0-dimethly-S-(l,2dicarbethoxyethyl)
phosphorodithioate:
It is less toxic than DDT and decomposes over a much shorter period of
time. With the suspension of DDT in pest control programs in 1965,
use of malathion has been increasingly widespread in Alaska's interior.
In spite of its low toxicity to animals, malathion is poisonous at
some level. Lethal doses for domestic sheep and cattle are 150 mg/kg
and 200 mg/kg. of body weight, respectively. The fatal dose of malathion
for a 70 kg man has been estimated to be 60 g, with some clinical exceptions
(McKee and Wolfe, 1963; Hayes, 1964). Dietary levels (ppm) producing
minimal or no effect after continuous feeding for 90 days to 2 years to
rats and dogs have been reported as 100-1000 and 100, respectively
(Lehman, 1965). On the other hand, malathion has been identified by gas
chromatography in extracts of water associated with several fish kills
(Garrison, Keith, and Alford, 1972).
In a study of malathion persistence in the soil near Fairbanks,
Alaska, during the summer of 1967, half of the sampling sites showed the
presence of malathion and its oxidation product, malaoxon, prior to
aerial spraying (Holty, 1970). Since there had been no ground spraying
since the summer of 1966, this would indicate that malathion was not
degrading in the environment as fast as anticipated. This is important
since it is then possible for the spring runoff to carry significant
quantities of the pesticide and its degradation products into streams
and rivers in the area. Retention of the malathion appears to depend on
the amount of rainfall, and the summer of 1966 had been very dry.
During the wetter summer of 1967, the post-spray soil samples showed a
rapid drop in the level of malathion except at sampling sites in "mucky"
soils which also increased noticeably in moisture as the amount of
rainfall accumulated (Figure 1).
Very little has been known about the aqueous photodecomposition of
malathion and nothing was known of its vapor phase stability under
atmospheric conditions and exposure to sunlight prior to this study.The work upon which this completion report is based was supported by
funds provided by the U. S. Department of the Interior, Office of Water
Research and Technology as authorized under the Water Resources Research
Act of 1964, Public Law 88-379, as amended
Entanglement in the Dicke model
We show how an ion trap, configured for the coherent manipulation of external
and internal quantum states, can be used to simulate the irreversible dynamics
of a collective angular momentum model known as the Dicke model. In the special
case of two ions, we show that entanglement is created in the coherently driven
steady state with linear driving. For the case of more than two ions we
calculate the entanglement between two ions in the steady state of the Dicke
model by tracing over all the other ions. The entanglement in the steady state
is a maximum for the parameter values corresponding roughly to a bifurcation of
a fixed point in the corresponding semiclassical dynamics. We conjecture that
this is a general mechanism for entanglement creation in driven dissipative
quantum systems.Comment: Minor changes: Reference added and references correcte
Evidence for charged critical behavior in the pyrochlore superconductor RbOs2O6
We analyze magnetic penetration depth data of the recently discovered
superconducting pyrochlore oxide RbOs2O6. Our results strongly suggest that in
RbOs2O6 charged critical fuctuations dominate the temperature dependence of the
magnetic penetration depth near Tc. This is in contrast to the mean-field
behavior observed in conventional superconductors and the uncharged critical
behavior found in nearly optimally doped cuprate superconductors. However, this
finding agrees with the theoretical predictions for charged criticality and the
charged criticality observed in underdoped YBa2Cu3O6.59.Comment: 5 pages, 4 figure
Integrated use of LANDSAT data for state resource management
There are no author-identified significant results in this report
A Deep Survey of HI-Selected Galaxies: The Sample and the Data
In a 21 cm neutral hydrogen survey of approximately 55 sq deg out to a
redshift of cz=8340 km/s, we have identified 75 extragalactic HI sources. These
objects comprise a well-defined sample of extragalactic sources chosen by means
that are independent of optical surface brightness selection effects. In this
paper we describe the Arecibo survey procedures and HI data, follow-up VLA HI
observations made of several unusual sources, and Kitt Peak B-, R-, and I-band
photometry for nearly all of the galaxies. We have also gathered information
for some of the optically detected galaxies within the same search volume. We
examine how samples generated by different types of search techniques overlap
with selection by HI flux. Only the least massive HI object, which is among the
lowest mass HI sources previously found, does not have a clear optical
counterpart, but a nearby bright star may hide low surface brightness emission.
However the newly-detected systems do have unusual optical properties. Most of
the 40 galaxies that were not previously identified in magnitude-limited
catalogs appear to be gas-dominated systems, and several of these systems have
HI mass-to-light ratios among the largest values ever previously found. These
gas-dominated objects also tend to have very blue colors, low surface
brightnesses, and no central bulges, which correlate strongly with their
relative star-to-gas content.Comment: 48 pages, 10 figures, Figure 3 included as 3 separate JPG images. To
appear in Ap J Supplement
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