826 research outputs found
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Coal gasification power generation, and product market study. Topical report, March 1, 1995--March 31, 1996
This Western Research Institute (WRI) project was part of a WRI Energy Resource Utilization Program to stimulate pilot-scale improved technologies projects to add value to coal resources in the Rocky Mountain region. The intent of this program is to assess the application potential of emerging technologies to western resources. The focus of this project is on a coal resource near the Wyoming/Colorado border, in Colorado. Energy Fuels Corporation/Kerr Coal Company operates a coal mine in Jackson County, Colorado. The coal produces 10,500 Btu/lb and has very low sulfur and ash contents. Kerr Coal Company is seeking advanced technology for alternate uses for this coal. This project was to have included a significant cost-share from the Kerr Coal Company ownership for a market survey of potential products and technical alternatives to be studied in the Rocky Mountain Region. The Energy Fuels Corporation/Kerr Coal Company and WRI originally proposed this work on a cost reimbursable basis. The total cost of the project was priced at 60,000.00 to be spent on market research for the project that never developed because of product market changes for the company. WRI and Kerr explored potential markets and new technologies for this resource. The first phase of this project as a preliminary study had studied fuel and nonfuel technical alternatives. Through related projects conducted at WRI, resource utilization was studied to find high-value materials that can be targeted for fuel and nonfuel use and eventually include other low-sulfur coals in the Rocky Mountain region. The six-month project work was spread over about a three-year period to observe, measure, and confirm over time-any trends in technology development that would lead to economic benefits in northern Colorado and southern Wyoming from coal gasification and power generation
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Activities to support the liquefied gaseous fuels spill test facility program. Final report
Approximately a hundred years ago the petrochemical industry was in its infancy, while the chemical industry was already well established. Today, both of these industries, which are almost indistinguishable, are a substantial part of the makeup of the U.S. economy and the lifestyle we enjoy. It is difficult to identify a single segment of our daily lives that isn`t affected by these industries and the products or services they make available for our use. Their survival and continued function in a competitive world market are necessary to maintain our current standard of living. The occurrence of accidents in these industries has two obvious effects: (1) the loss of product during the accident and future productivity because of loss of a portion of a facility or transport medium, and (2) the potential loss of life or injury to individuals, whether workers, emergency responders, or members of the general public. A great deal of work has been conducted at the Liquefied Gaseous Fuels Spill test Facility (LGFSTF) on hazardous spills. WRI has conducted accident investigations as well as provided information on the research results via the internet and bibliographies
The effect of two-temperature post-shock accretion flow on the linear polarization pulse in magnetic cataclysmic variables
The temperatures of electrons and ions in the post-shock accretion region of
a magnetic cataclysmic variable (mCV) will be equal at sufficiently high mass
flow rates or for sufficiently weak magnetic fields. At lower mass flow rates
or in stronger magnetic fields, efficient cyclotron cooling will cool the
electrons faster than the electrons can cool the ions and a two-temperature
flow will result. Here we investigate the differences in polarized radiation
expected from mCV post-shock accretion columns modeled with one- and
two-temperature hydrodynamics. In an mCV model with one accretion region, a
magnetic field >~30 MG and a specific mass flow rate of ~0.5 g/cm/cm/s, along
with a relatively generic geometric orientation of the system, we find that in
the ultraviolet either a single linear polarization pulse per binary orbit or
two pulses per binary orbit can be expected, depending on the accretion column
hydrodynamic structure (one- or two-temperature) modeled. Under conditions
where the physical flow is two-temperature, one pulse per orbit is predicted
from a single accretion region where a one-temperature model predicts two
pulses. The intensity light curves show similar pulse behavior but there is
very little difference between the circular polarization predictions of one-
and two-temperature models. Such discrepancies indicate that it is important to
model some aspect of two-temperature flow in indirect imaging procedures, like
Stokes imaging, especially at the edges of extended accretion regions, were the
specific mass flow is low, and especially for ultraviolet data.Comment: Accepted for publication in Astrophysics & Space Scienc
Use of Contingent Valuation to Assess Farmer Preference for On-farm Conservation of Minor Millets: Case from South India
Smallholder farmers all over the world, particularly in regions of rich agro-biodiversity contribute to on-farm conservation. Past and present agricultural progress could not have happened neither without these genetic resources nor the associated farmer knowledge. Six species of minor millets are grown in India on more than 2 million hectares. The Kolli Hills in Tamil Nadu has been a region where five of these millet species have been under cultivation over the last several hundred years. These minor millets are currently under threat due to high competition from tapioca (cassava) as well as easy access to PDS rice at low cost. Over last three decades there has been decline in the millet area and number of farmers cultivating these species. It is in this context that this study attempts to examine the role of farmer incentive mechanisms to conserve minor millets in Kolli Hills. The millet varieties existing in the study area were classified either as most preferred varieties (MPVs) or least preferred varieties (LPVs) by the farmer respondents based on their yield and consumption preferences. The farmer willingness to accept compensation to participate in the conservation programme is estimated using a contingent valuation method (CVM). Seemingly unrelated bivariate probit regression was used to estimate the determinants of willing to participate in on-farm conservation of minor millets. The result shows that the impact of bid value is significant and positive to participate in the on-farm millet conservation of MPVs. The farmers participating is millet related organization are willing to accept lower compensation for MPVs and higher for LPVs compared to farmers who are not participating in such organization
Generation of arbitrary two dimensional motional state of a trapped ion
We present a scheme to generate an arbitrary two-dimensional quantum state of
motion of a trapped ion. This proposal is based on a sequence of laser pulses,
which are tuned appropriately to control transitions on the sidebands of two
modes of vibration. Not more than laser pulses are needed to
generate a pure state with upper phonon number and in the and
direction respectively.Comment: to appear in PR
Efficacy of beta radiation in prevention of post-angioplasty restenosis
Restenosis remains a major limitation of coronary angioplasty in spite of major advances in techniques and technology. Recent studies have demonstrated that ionizing radiation may limit the degree of this problem. Gamma radiation has been shown to be effective in reducing in stent restenosis in humans, and beta radiation following encouraging results in animals has been shown to be feasible in humans. The objective of this study was to assess the feasibility of a 5 F non-centered catheter to deliver beta radiation emitting seeds to the lesion site post angioplasty and its effect on restenosis. Following successful angioplasty, patients were randomized to treatment with 12, 14 or 16 Gy at the angioplasty site. This was delivered with a 5 F non-centered catheter. Twelve beta radiation emitting seeds (90Sr/Y) were delivered to an area 3 cm in length to cover the angioplasty site. Angiographic follow-up was performed at 6 months. Baseline and follow-up angiograms were performed by blinded investigators at a core laboratory. This interim report comprises the first 35 patients to complete 6-month angiographic follow-up. There were no major radiation incidents. Four patients had evidence of angiographic restenosis. The MLD (mm) and percent stenosis were 0.77 +/- 0.27/72.5 +/- 8.6 pre angioplasty, 2.08 +/- 0.4/25.7 +/- 9.8 post angioplasty and radiation and 2.05 +/- 0.59/25.7 +/- 19.8 at follow-up respectively. CONCLUSION: Beta radiation can be feasibly and safely delivered post coronary angioplasty with a very encouraging reduction of restenosis
Five Dimensional Rotating Black Hole in a Uniform Magnetic Field. The Gyromagnetic Ratio
In four dimensional general relativity, the fact that a Killing vector in a
vacuum spacetime serves as a vector potential for a test Maxwell field provides
one with an elegant way of describing the behaviour of electromagnetic fields
near a rotating Kerr black hole immersed in a uniform magnetic field. We use a
similar approach to examine the case of a five dimensional rotating black hole
placed in a uniform magnetic field of configuration with bi-azimuthal symmetry,
that is aligned with the angular momenta of the Myers-Perry spacetime. Assuming
that the black hole may also possess a small electric charge we construct the
5-vector potential of the electromagnetic field in the Myers-Perry metric using
its three commuting Killing vector fields. We show that, like its four
dimensional counterparts, the five dimensional Myers-Perry black hole rotating
in a uniform magnetic field produces an inductive potential difference between
the event horizon and an infinitely distant surface. This potential difference
is determined by a superposition of two independent Coulomb fields consistent
with the two angular momenta of the black hole and two nonvanishing components
of the magnetic field. We also show that a weakly charged rotating black hole
in five dimensions possesses two independent magnetic dipole moments specified
in terms of its electric charge, mass, and angular momentum parameters. We
prove that a five dimensional weakly charged Myers-Perry black hole must have
the value of the gyromagnetic ratio g=3.Comment: 23 pages, REVTEX, v2: Minor changes, v3: Minor change
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