Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

Science.gov (United States)

... PRODUCTION OF TIGHT OIL-GAS BEARING ROCKS, AND IS ALSO EMPLOYED FOR THE DEVELOPMENT OF GEOTHERMAL RESERVOIRS. ...

Energy Technology Data Exchange (ETDEWEB)

Gas hydrates are crystalline substances composed of water and gas, in which a solid-water-lattice accommodates gas molecules in a cage-like structure. Gas hydrates are globally widespread in permafrost regions and beneath the sea in sediment of outer continental margins. While methane, propane, and other gases can be included in the clathrate structure, methane hydrates appear to be the most common in nature. The amount of methane sequestered in gas hydrates is probably enormous, but estimates are speculative and range over three orders of magnitude from about 100,000 to 270,000,000 trillion cubic feet. The amount of gas in the hydrate reservoirs of the world greedy exceeds the volume of known conventional gas reserves. Gas hydrates also represent a significant drilling and production hazard. A ...

International Nuclear Information System (INIS)

The massive star-forming core MM1 of W75N was observed using the Submillimeter Array with #approx#1'' and 2'' spatial resolutions at 217 and 347 GHz, respectively. From the 217 GHz continuum we found that the MM1 core consists of two sources, separated by about 1'': MM1a (#approx#0.6 M_s_u_n) and MM1b (#approx#1.4 M_s_u_n), located near the radio continuum sources VLA 2/VLA 3 and VLA 1, respectively. Within MM1b, two gas clumps were found to be expanding away from VLA 1 at about #+-#3 km s"-"1, as a result of the most recent star formation activity in the region. Observed molecular lines show emission peaks at two positions, MM1a and MM1b: sulfur-bearing species have emission peaks toward MM1a, but methanol and saturated species at MM1b. We identified high-temperature (#approx#200 K) gas toward MM1a and the hot core in MM1b. This segregation may result from the evolution of the massive star-forming ...

Energy Technology Data Exchange (ETDEWEB)

A method is described for increasing pressure in geologic oil-bearing structures by gas production due to microbial activity. There is added to an oil-bearing structure an anaerobic micro-organism (Methanobacterium termoautotroficum), a culture medium and formic acid. The formic acid is converted to carbon dioxide and methane gases resulting in increased pressure in the structures. Methanobacterium termoautotroficum cannot split formic acid into CO/sub 2/ and H/sub 2/ but it can produce methane from these 2 gases. 4 claims.

Energy Technology Data Exchange (ETDEWEB)

In this effort, the nonlinear responses and stability of a spindle system supported by ball bearings are presented. The dynamics of this system is described by a set of second order differential equations with a nonlinear piecewise smooth force. The Floquet theory is applied to investigate the stability of the periodic solution. Due to the loss of contact between the raceways and balls in the ball bearing, the bending of the frequency response curves switch to the left at the weak resonance region, which is similar to the frequency response curves of a system with a soft spring. With the decrease of the bearing clearance, the bending of the frequency response curves switch to the right, which is similar to the frequency response curves of a system with a hard spring. Increase of the frequency ratio, the bending of frequency response curves transforms from left to right. The route to chaos through a ...

Energy Technology Data Exchange (ETDEWEB)

This presentation described the geology of the Kootenay, Gething, Gates, Brazeau and Coalspur Formations in the potential gas-bearing coal zones of the Alberta Foothills/Mountains. The future potential of this region for coalbed methane (CBM) exploitation was discussed, based on available data from drilling activity and the results of a recent coal desorption and adsorption study in the Val d'Or seam of the Coalspur formation. The gas content of the 5 coal zones was evaluated and compared with previous CBM exploration in the area. For evaluation purposes, the coal zones were divided into shallow and deep coal zones. The potential gas content of the shallow coal zones is approximately 31 Tcf of CBM. This is considered an inferred, initial, in-place, CBM resource estimate based on limited data. The gas content of deep zones is approximately 99 Tcf of in-place CBM ...

Energy Technology Data Exchange (ETDEWEB)

Ceramic antifriction bearings were introduced in excellent characterics and application. In main shaft use bearings of the machine tool, to be heightened in efficiency and accuracy by the heightening in speed, centrifugal load to the outer ring is not negligible to shorten the bearing in life. Also ball bearings with a contact angle are easily corroded by a very strong revolution slide due to the gyromoment. The use of such light weight material as silicon nitride's can design the lengthening in life. Also the utilization of high rigidity can prevent the inner ring from expanding by centrifugal force and enable the machining to be with a high accuracy. Ceramic rolling element is excellent also in backing resistant property and effective on the oily film cut. With heat resistant property, it maintains hardness even at high temperature. Such excellent characteristics being utilized, the fine ...

Energy Technology Data Exchange (ETDEWEB)

The pipelines is provided for gases, particluarly helium, at temperature of about 1000/sup 0/C (pressure about 40 bar) and is used as the connection be tween a gas cooled high temperature reactor and a heat load. The pipe consists of a temperature-resistant inner tube, which is composed of several pipe sections, which are supported on ball bearings, and a gas tight pressurised outer tube. There are supports and insulation between the two tubes. The sub-claims concern fixing of and bearings for the pipe sections. The description is very detailed and supplemented by drawings.

Energy Technology Data Exchange (ETDEWEB)

This paper presents a numerical study on the formation history of coalbed methane (CBM) reservoir in the southeast edge of Ordos Basin, China. The coal seams studied belong to the Late Palaeozoic coal-bearing series. These coal seams have a burial history and experienced the process of subsidence, rapid subsidence alternated with uplift and then uplift, sequentially, and underwent the geothermal actions at normal, extremely high, and then normal temperatures, respectively. Coal organic matter of the coal seams matured in the Triassic Period and in the Late Jurassic to Early Cretaceous Period. The results from numerical simulation reveal that CBM reservoir evolution history can be classified into five stages, namely primary, initial, stagnant, active and dissipative stages. In the first (primary) stage, coal rank was very low and there was little methane generated and stored in the coal seams. In the second (initial) stage, the coal was converted to middle-high ...

Energy Technology Data Exchange (ETDEWEB)

The invention is associated with organic geochemistry and may be used in conducting geological exploration operations for oil and gas. The purpose of the invention is to increase the precision of the method for determining the genesis of bitumoids. This is achieved through determining the isotopic composition of nickel or vanadium and from the anomalously high values of the isotopic ratio of Ni-58 to Ni-62 or from the anomalously low values of the isotopic ratio of vanadium, a conclusion is drawn about the epigenetic nature of the bitumoids. The proposed method is characterized by greater resolution due to the fact that the values of the isotopic ratios for oil bearing and water bearing structures are essentially not superimposed. The proposed method exceeds the resolution of metal metering studies in conducting geological exploration for oil and gas by 2 to 3 times.

Energy Technology Data Exchange (ETDEWEB)

A total of nine papers were presented at the course with the following titles: peat accumulation and coal basins; coal composition; coal quality; sedimentary environments of coal; generation, storage and migration of natural gas in coal bed reservoirs; geophysical log interpretation; the Ardley coal zone of central Alberta; stratigraphy and sedimentary environment of the Coalspur Formation; and the coal-bearing Luscar Group of western Alberta. All of these papers have been abstracted separately.

Science.gov (United States)

Radial Halbach magnetic bearings have been investigated as part of an effort to develop increasingly

Energy Technology Data Exchange (ETDEWEB)

Spectral line intensity data are presented for ionized hydrogen regions in the giant spiral galaxy M101. The influence of interstellar extinction is assessed and electron temperatures of the gas clouds are derived.

Science.gov (United States)

roller bearing with a one-piece inner ring. The lubricant experimental data on high-speed roller .... roller bearing. The outer ring of the test bearing was ...

Energy Technology Data Exchange (ETDEWEB)

Grout has been evaluated as a means of containing low-level radioactive waste for long-term disposal. Concerns about hydrogen and reactive gas generation in the Hanford Site grout disposal facility lead to the development of the G3 model, which has predicted buildup of radiolytically formed gases in the grout region and their migration to air-filled regions. The G3 model is a one-dimensional code that couples models of gas diffusion with two-phase gas and liquid flow. It was coupled to a compartment diffusion model and these models predicted the concentrations of hydrogen I nitrous oxide, and other gases in air-filled regions of the grout disposal facility. The results have served as the technical basis for safety studies. A unique finding of the G3 model was that a liquid return, or expulsion of unbound liquid from the grout region, could ...

Energy Technology Data Exchange (ETDEWEB)

Delayed cerebral necroses after irradiation are to be divided into hemispheric and midline lesions, as they differ from each other in several aspects. Apart from the symptoms, they are differing in the duration of latency, in the course and prognosis, and also with regard to morphology. Though there is no doubt that radiation tolerance of cerebral midline structures is relatively limited, on biological grounds, evidence of a difference between the tolerated doses could not be given from the existent inhomogeneous radiation data, with the help of the NSD-concept. Radiation planning for the region of the head, nevertheless, carefully should avoid in every case to involve the structures of the cerebral midline.

Science.gov (United States)

... Development Tapered Roller Bearing Program . . . 11 ... 98 61 Tapered Roller Bearing Component t Identification..... 104 ...

International Nuclear Information System (INIS)

The Caspian Sea (CS) region's oil and gas potential has attracted much attention since the breakup of the Soviet Union. The nations in the CS region, namely Azerbaijan, Iran, Kazakhstan, Russia, Turkmenistan, and Uzbekistan, are already major energy producers, and production will increase with additional investment, technology, and the development of new export outlets. Oil and gas transportation is a crucial and contentious issue in the CS/Central Asia regions. The main objective of the present study is to investigate Turkey's natural gas (NG) pipelines and its role in the CS region. NG consumption has started in 1987 at 0.5 billion cubic meter (Bcm) and reached 16 Bcm in 2001. It is also projected that NG consumption will reach 55 and 82 Bcm annually in 2010 and 2020, respectively. Recent developments have shown once again Turkey's role on ...

Energy Technology Data Exchange (ETDEWEB)

The Minami-Iwaki trunk line now under construction by Tokyo Electric Power Company is an UHV transmission line which covers 130km from the central region of the Abukuma highlands, Fukushima Prefecture, through the northern ridge of the Kanto Plain to Imaichi City, Tochigi Prefecture and has 235 steel towers. About 30% of the ground along the above route is mainly layers of sand and gravel. Accordingly it has become urgent to design rationally the pile foundations in the sand and gravel layers. Hence the company has studied an estimation method of the ultimate bearing power of cast-in-place piles penetrating the sand and gravel layers and the displacement of pile heads. In this report, the result of the above study is described. The company has so far used the equations in accordance to the Meyerhof equations for the estimations of the ultimate bearing power and this time, this equations have been examined for its ...

International Nuclear Information System (INIS)

Several materials, lenses, dry bearings and cables were exposed to a tritiated moisture environment to study the behavior of tritium contamination on candidate materials for ITER remote handling equipment. To optimize the tritium removal procedure, decontamination experiments using a gas purge with three different moisture concentrations were also performed. The surface tritium concentrations of CeO_2 containing alkaline barium glass (NB), CeO_2 containing lead glass (LX) and synthetic quartz (Quartz) after the exposure experiments were 7.80, 10.94 and 0.67 Bq/cm"2, respectively. It was found that the tritium concentration was influenced by the compositions of the materials. The concentrations of tritium on type 831 (solid lubrication material: graphite) and type 237 (solid lubrication material: tungsten disulfate) dry bearings after the exposure experiments were 89.80 and 31.78 Bq/cm"2, respectively. The tritium ...

International Nuclear Information System (INIS)

The presence of an extraneous light gas must be taken into account in consideration of centrifugal separation of uranium isotopes, when there is inevitable leakage of such a gas through the gas sealant and/or leaking in from the atmosphere. Consideration is first given to the influence of the presence of the light gas on the maximum separative power. Then the basic equation for isotope separation containing a light gas is derived from Hirschfelder's diffusion equations. This equation is solved and the separative performance is expressed in terms of the shape factor and reflux parameter. The formulas for expressing the flow configurations of the gases are obtained for a simple model in which inflow and outflow prevail throughout the centrifuge. The corresponding equation for a model in which the gases flow in two concentric thin streams is also derived. It is concluded that the ...

Science.gov (United States)

Prepared to make housing project managers, maintenance engineering staff, and designers and architects of HUD - assisted and HUD - insured housing projects and mobile home parks aware of their responsibilities under the Natural Gas Pipeline Safety Act, this handbook provides technical guidance for the reduction of gas leaks and the handling of gas leak incidents in residential areas. The hazards of natural gas, concern over gas safety in residential areas, applicable codes and standards, and sources of information and help are reviewed, along with maintenance and engineering considerations relating to gas pipe failures, the detection of gas leaks, appliance servicing, and pipe installation, repair, and replacement. Housing management considerations are also examined, with attention to recordkeeping and reporting, emergency contingency ...

International Nuclear Information System (INIS)

By the methods of small-angle X-ray scattering and translucent electron microscopy the existence of inhomogeneity of electron density in hydrogenated films of amorphous silicon is confirmed. The decreased density regions are extended and form a branched network of channels oriented mostly by the normal direction to the films surface. The typical size of the decreased density regions network constitutes 10 nm in the 100-800 nm films thickness range. The increase of hydrogen total partial pressure in gas mixture in case of films growth results at first in the decrease of extension of these regions and than to micropores generation in the network nodal points of the decreased electron density regions.

Energy Technology Data Exchange (ETDEWEB)

A centrifugal pump was developed for the efficient and reliable transfer of liquid helium in space. The pump can be used to refill cryostats on orbiting satellites which use liquid helium for refrigeration at extremely low temperatures. The pump meets the head and flow requirements of on-orbit helium transfer: a flow rate of 800 L/hr at a head of 128 J/kg. The overall pump efficiency at the design point is 0.45. The design head and flow requirements are met with zero net positive suction head, which is the condition in an orbiting helium supply Dewar. The mass transfer efficiency calculated for a space transfer operation is 0.99. Steel ball bearings are used with gas fiber-reinforced teflon retainers to provide solid lubrication. These bearings have demonstrated the longest life in liquid helium endurance tests under simulated pumping conditions. Technology developed in the project also has application for liquid helium ...

Energy Technology Data Exchange (ETDEWEB)

This project dealt with use of condensing heat exchangers to recover water vapor from flue gas at coal-fired power plants. Pilot-scale heat transfer tests were performed to determine the relationship between flue gas moisture concentration, heat exchanger design and operating conditions, and water vapor condensation rate. The tests also determined the extent to which the condensation processes for water and acid vapors in flue gas can be made to occur separately in different heat transfer sections. The results showed flue gas water vapor condensed in the low temperature region of the heat exchanger system, with water capture efficiencies depending strongly on flue gas moisture content, cooling water inlet temperature, heat exchanger design and flue gas and cooling water flow rates. Sulfuric acid vapor condensed in both the high temperature ...

Energy Technology Data Exchange (ETDEWEB)

The history of the political process surrounding regulations is traced from the 1930s, when the natural gas industry and the Federal Power Commission were in their infancy. The author traces the changing mandate that Congress has provided the regulators and the instincts for self-preservation that these bureaucrats have manifested when they suspected a change in presidential administration or a new decision from the Supreme Court. Natural gas has been one political issue that has split Congress by region. The economic interests of producer and consumer states have often been at such odds that regulation has involved the question of redistribution of wealth among regions as well as between households and industry. The picture is complicated by the link between gas production and distribution and the production and distribution of coal and oil. 12 figures, 25 tables.

Energy Technology Data Exchange (ETDEWEB)

The Externally-Fired Combined Cycle (EFCC) offers a method for operating high-efficiency gas and steam turbine combined cycles on coal. In the EFCC, an air heater replaces the gas turbine combustor so that the turbine can be indirectly fired. Ceramic materials are required for the heat exchange surfaces to accommodate the operating temperatures of modern gas turbines. The ceramic air heater or heat exchanger is the focus of this program, and the two primary objectives are (1) to demonstrate that a ceramic air heater can be reliably pressurized to a level of 225 psia (1.5 MPa); and (2) to show that the air heater can withstand exposure to the products of coal combustion at elevated temperatures. By replacing the gas turbine combustor with a ceramic air heater, the cycle can use coal or other ash-bearing fuels. Numerous programs have attempted to fuel high efficiency ...

Science.gov (United States)

The Cretaceous rudist-bearing carbonates of the Arabian Gulf region are proven exploration targets for hydrocarbons and form the reservoirs of a number of giant fields, including Bu Hasa, Fateh, Fahud, Idd El Shargi, Rumaila, Shaybah, and Shah. Rudist buildups occur in three principal formations: (1) Aptian Shuaiba, (2) Cenomanian Mishrif, and (3) Maastrichtian Simsima. A regional subaerial unconformity marks the upper boundary of each of these formations. Associated with the rudists that dominate the Shuaiba Formation are calcareous algal crusts, foraminifera, and echinoid plates, which accumulated in mudstone, packstone, and carbonate sands. The Mishrif Formation contains mollusk fragments, bioclasitc packstones to grainstones, miliolid and nonrudist bivalves in muddy limestones, and rudist (mainly radiolitids and caprinids) conglomeratic floatstones, with fragmented rudists mixed with wackestone lithoclasts. The Mishrif ...

Science.gov (United States)

A new renicolid cercaria, Cercaria kuwaitae X sp. n., from the prosobranch gastropod Cerithium scabridum from Kuwait Bay is described. The new cercaria is nonstyleted gymnocephalous with voluminous Y-shaped excretory vesicle, flame cell formula 2[(3 + 3 + 3) + (3 + 3 + 3)] = 36, and without caudal fins. Surface topography of the new cercaria is studied by scanning electron microscopy. Domed papillae are abundant on the anterior and lateral aspects of the body, ciliated papillae are sparse dorsally. The ventral sucker bears nine domed papillae. Domed papillae form two circles around the oral sucker with three circles of spines in between. This is the first renicolid cercaria to be recorded in a gastropod from the Arabian Gulf region. PMID:9789783

Energy Technology Data Exchange (ETDEWEB)

The manual provides design information for four groups of sediment control structures and treatments which are suitable for use on small areas in surface coal mining. A detailed design procedure is given for each group which will estimate the total amount of settleable solids from a small area with a sediment control structure or treatment for a specific design storm. A procedure is also given for estimating the mean annual sediment yield from a small area. Information on design, installation, maintenance and cost is given for each sediment control measure. Methods for determining the maximum allowable area for each sediment control measure and for design of combined sediment control systems are presented. The design procedures contain numerous nomographs, graphs, and worksheets to facilitate the use of the design procedure. The sediment control measures, design procedures, and materials in the manual are applicable to coal-bearing regions of ...

Energy Technology Data Exchange (ETDEWEB)

Gene analysis was used to determined the presence, abundance and phylogenetic affiliation of methanogens that exist in gas-hydrate-bearing sediment samples obtained from 23 drill cores from the JAPEX/JNOC/GSC et al. Mallik 5L-38 gas hydrate research well. Rates of methane production were examined using sediment-inoculated enrichments containing {sup 14}C-labeled carbon substrates, carbon dioxide and acetate. Archaeal 16S rDNA was only detected in 6 of the samples, resulting in 8 sequences with relationships to the Miscellaneous Crenarchaeotic Group (7 clones) and the Subsurface Euryarchaeotic Group (1 clone). The single Euryarchaeota sequence did not appear to be related to methanogens. Subsamples from the cores showed variable results upon DNA extraction and amplification. Methanogenic Coenzyme M (CoM) was detected in 13 of the 20 cores, but methanogenic methyl CoM reductase genes were not amplified from the samples when using a sensitive ...

International Nuclear Information System (INIS)

Short-lived fission gas release from fuel pellets during irradiation was investigated based on the experimental results of the gas-flow rigs irradiated in the Halden Heavy Water Reactor (HBWR). The release-to-birth (R/B) rates of short-lived fission gas were measured by means of gas-flow measurement during the irradiation experiments. Surface-to-volume (S/V) ratios of fuel pellets and diffusion coefficients of short-lived fission gas release were evaluated from the obtained (R/B) values. The increase of (S/V) ratio agreed well with the point where the fuel temperature exceeded the threshold of 1% fission gas release. This indicates that the interlinkage of fission gas bubbles occurred there. The evaluated diffusion coefficients scattered in the range between 10"-"2"3 and 10"-"1"7 m"2/s, and the effects of fuel type (UO_2 or MOX) were not ...

British Library Electronic Table of Contents (United Kingdom)

Summary The aroma impact volatiles of twenty-four pine honey samples produced in Marmaris, Data and Fethiye regions of Turkey were evaluated by solid phase micro extraction/gas chromatography/mass spectrometry (MS) technique and the results were evaluated by using the analysis of variance and Duncan tests. A total of eight common volatiles nonanal, nonanol, decanal, octanal, 16-oxosalutaridine, dodecanal, nonadecane and pentadecane were detected in three regions. The total area of the common volatiles were 73.01%, 78.10% and 73.91% in Marmaris, Data, and Fethiye regions, respectively. There were not significant differences (P-<-0.05) between the common volatiles detected in pine honey samples from three different regions. The major contributers to the pine honey aroma seems to be nonanal (...

International Nuclear Information System (INIS)

Since high resolution sequence stratigraphy was introduced into China by DENG Hong-wen in 1995, it has been experienced two development stages in China which are the beginning stage of theory research and development of theory research and application, and the stage of theoretical maturity and widely application that is going into. It is proved by practices that high resolution sequence stratigraphy plays more and more important roles in the exploration and development of oil and gas in Chinese continental oil-bearing basin and the research field spreads to the exploration of coal mine, uranium mine and other strata deposits. However, the theory of high resolution sequence stratigraphy still has some shortages, it should be improved in many aspects. The authors point out that high resolution sequence stratigraphy should be characterized quantitatively and modelized by computer techniques. (authors)

Energy Technology Data Exchange (ETDEWEB)

Gas quenching for the hardening of steel parts is a lower-pollution alternative to quenching in quenchants such as oil or salt. As the surfaces of the cooled parts remain clean after gas quenching, there is no need to wash them after heat treatment, which reduces the consumption of oils and detergents. The fire risk and ventilation requirements of oil quenching are eliminated. In addition, some trials have shown that gas quenching has a positive effect on distortion, representing a saving in finishing work and thus a reduction in costs. Today, gas quenching is used almost solely in vacuum furnaces. Quenching is normally performed in the same chamber as heating, which means that besides quenching the batch, the quenching system must also remove heat from the heating elements and insulation of the furnace. Previous trials performed by IVF have shown that gas quenching with helium of ...

Science.gov (United States)

... d Diameter of ro.'ling element of a cylindrical roller bearing ... L Life (B-10) of a cyl.ndrical roller bearing LACA Contact ratio ...

Science.gov (United States)

... Accession Number : AD0164404. Title : Ball and Roller Bearing Retainer Improvement for High Speed Operation. Descriptive Note : Patent,. ...

British Library Electronic Table of Contents (United Kingdom)

Remote, offshore gas reserves have long been a challenging deepwater petroleum resource to tap. Natural gas in many offshore regions is plentiful, but lacks access to the market because of the logistical challenges and costs. Most large offshore gas discoveries are capped, and gas associated with oil production is re-injected into the reservoir or is flared. A more attractive option is to convert the gas into a liquid product on a floating production, storage, and offloading (FPSO) vessel. However, some conventional process technologies are not well suited for operation on floating vessels that are highly space and weight constrained and may challenge vessel stability during inclement weather. Microchannel process technology units under development offer intensified processes that are suit...

Energy Technology Data Exchange (ETDEWEB)

Device for separating and collecting ultrafine atomized powder from the gas stream of a gas atomizing apparatus comprises a housing having an interior wall oriented at an angle relative to horizontal so as to form a downwardly converging, conical expansion chamber, an inlet conduit communicated to the expansion chamber proximate an upper region thereof for receiving the gas stream, and an outlet proximate a lower region of the expansion chamber. The inlet conduit is oriented at a compound inclined angle (with respect to horizontal) selected to promote separation and collection of powder from the gas stream in the expansion chamber. The compound angle comprises a first entrance angle that is greater than the angle of repose of the powder on the housing interior wall such that any powder accumulation in the inlet conduit tends to flow down the wall toward the ...

International Nuclear Information System (INIS)

We investigate the relationship between spiral arms and star formation in the grand-design spirals NGC 5194 and NGC 628 and in the flocculent spiral NGC 6946. Filtered maps of near-IR (3.6 #mu#m) emission allow us to identify 'arm regions' that should correspond to regions of stellar mass density enhancements. The two grand-design spirals show a clear two-armed structure, while NGC 6946 is more complex. We examine these arm and interarm regions, looking at maps that trace recent star formation-far-ultraviolet (GALEX NGS) and 24 #mu#m emission (Spitzer SINGS)-and cold gas-CO (HERACLES) and H I (THINGS). We find the star formation tracers and CO more concentrated in the spiral arms than the stellar 3.6 #mu#m flux. If we define the spiral arms as the 25% highest pixels in the filtered 3.6 #mu#m images, we find that the majority (60%) of star formation tracers occur in the interarm ...

Energy Technology Data Exchange (ETDEWEB)

The ARE progress report discusses the following issues: Economic development and its effects on power supply; Deregulation of the electricity and gas market; Competition between regional utilities; Energy policy of the new German government; European regulations; Legislation on energy supply; Energy supply and cartel law; Regional supply in the East German states. [German] Der Taetigkeitsbericht der ARE befasst sich mit folgenden Themen: Gesamtwirtschaftliche Entwicklung und ihre Auswirkung auf die Energiewirtschaft, Oeffnung des Monopoles fuer Strom und Gas, Wettbewerb der regionalen Energieversorger, Energiepolitik der neuen Bundesregierung, Europaeische Richtlininen, energiewirtschaftsrecht, Versorgungswirtschaft und Kartellrecht und der Regionalversorgung in den neuen Bundeslaendern.

Energy Technology Data Exchange (ETDEWEB)

The authors address the question of the limitations on voltage and current transfer to loads in magnetic storage systems utilizing microsecond conduction time plasma opening switches. They propose that the limitation of performance results from neutral atoms that are not entrained into the ionized material that is driven by the magnetic field of the rising generator current. Evidence in support of this proposition is gathered from experiments performed on the Ace-4 and Hawk generators. They set forth a theory to describe the effect of neutrals on the electrical performance of plasma opening switches. The neutral gas is assumed to be present in the region between the moving plasma mass and the generator, primarily in the region in which the plasma is injected initially. The essential elements of the theory are a weak photoionization source to seed the gas with a low concentration of electrons, and joule ...

Energy Technology Data Exchange (ETDEWEB)

Accurate prediction of tube surface temperature is important for determining whether accelerated superheater corrosion will occur in kraft recovery boilers. A heat transfer model, which combines an iterative numerical solution scheme with a more realistic flue gas flow field obtained from the CFD code FLUENT, has been developed to predict the tube, steam and flue gas temperatures in the superheater region. Results of tests performed for a recovery boiler show that temperatures predicted using the model are in good agreement with actual temperatures measured using thermocouples. The presence of a large flue gas recirculation zone above the bullnose is shown to have an adverse effect on the heat transfer in the superheater region. 9 refs., 12 figs., 1 tab.

Energy Technology Data Exchange (ETDEWEB)

In pursuing its mission of helping U.S. independent oil and gas producers make timely, informed technology decisions, the Petroleum Technology Transfer Council (PTTC) functions as a cohesive national organization that implements industry's directives through active regional programs. The role of the national headquarters (HQ) organization includes planning and managing the PTTC program, conducting nation-wide technology transfer activities, and implementing a comprehensive communications effort. PTTC relies on 10 Regional Lead Organizations (RLOs) as its main program delivery mechanism to industry. Through its regions, PTTC connects with independent oil and gas producers--through technology workshops, resources centers, websites, newsletters, and other outreach efforts. The organization effectively combines federal, state, and industry funding to achieve important goals for ...

CERN Document Server

Spatially resolved studies of star forming regions show that the assumption of spherical geometry is not realistic in most cases, with a major complication posed by the gas being ionised by multiple non-centrally located stars or star clusters. We try to isolate the effects of multiple non-centrally located stars on the temperature and ionisation structure of HII regions, via the construction of 3D photoionisation models using the 3D Monte Carlo photoionisation code MOCASSIN. We find that the true temperature fluctuations due to the stellar distribution (as opposed to the large-scale temperature gradients due to other gas properties) are small in all cases and not a significant cause of error in metallicity studies. Strong emission lines from HII regions are often used to study the metallicity of star-forming regions. We compare integrated emission line spectra ...

Energy Technology Data Exchange (ETDEWEB)

The new multi-purpose oxygen cupola furnace is a coke-fired shaft furnace that is operated on pure oxygen. The top gas is recirculated, and the fumes are drawn off at temperatures ranging from 800 to 1 000 C. The furnace offers the possibility of melting down contaminated and zinc-bearing scrap without the occurrence of any environment-polluting gas emissions. The absence of nitrogen ballast permits a high energy efficiency. (orig.) [Deutsch] Der neue Mehrzweck-Sauerstoff-Kupolofen ist ein koksbeheizter Schachtofen, der mit reinem Sauerstoff betrieben wird. Das Gichtgas wird im Kreislauf gefuehrt, und das Abgas wird aus einem Bereich mit Temperaturen von 800 bis 1 000 C abgefuehrt. Der Ofen bietet die Moeglichkeit, verunreinigte und zinkhaltige Schrotte einzuschmelzen, ohne dass umweltbelastende Gasemissionen auftreten. Der fehlende Stickstoffbalast bewirkt einen hohen energetischen Wirkungsgrad. (orig.)

International Nuclear Information System (INIS)

The advantages and disadvantages of single-point or double-point bearing of rotors with several single shafts are illustrated by examples from the KWU series. The design features of modern bearings are described. Some results from the test program for the development of these bearings are reported. In the last section the vibration behavior of the shafts is considered. Various phenomena - like self-excited vibrations and those caused by unbalance or the influence of partial admission - are briefly discussed. (orig.).

International Science & Technology Center (ISTC)

Multi-functional Bioactive Nano-structured Coatings for Load-Bearing Implants

KoreaScience (Korea)

Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The usually low wear resistance of titanium materials can be increased by the thermochemical surface treatment nitriding. In result of comparative investigations of gas and plasma nitriding it will be shown that it is possible to obtain a specific variation of the properties in the highly stressed case by means of these both technologies on example of the ({alpha}+{beta}) alloy Ti-6Al-4V. Gas and plasma nitriding was carried out in the temperature range from 650 to 800 C over 4 to 48 h in different gas atmospheres, i.e. 100% NH{sub 3} (gas), 100% N{sub 2} (gas and plasma), 20% H{sub 2} + 80% N{sub 2} and 20% Ar + 20% H{sub 2} (plasma). The temperature range was fixed in the middle of ({alpha}+{beta}) region, because the core properties are influenced negative in the field of {beta}-transustemperature. The relations between the applied nitriding technologies, the ...

Energy Technology Data Exchange (ETDEWEB)

The Externally-Fired Combined Cycle (EFCC) is an attractive emerging technology for powering high efficiency combined gas and steam turbine cycles with coal or other ash bearing fuels. In the EFCC, the heat input to a gas turbine is supplied indirectly through a ceramic air heater. The air heater, along with an atmospheric coal combustor and ancillary equipment, replaces the conventional gas turbine combustor. A steam generator located downstream from the ceramic air heater and steam turbine cycle, along with an exhaust cleanup system, completes the combined cycle. A key element of the EFCC Development Program, the 25 MMBtu/h heat-input Kennebunk Test Facility (KTF), has recently begun operation. The KTF has been operating with natural gas and will begin operating with coal in early 1995. The US Department of Energy selected an EFCC repowering of the Pennsylvania Electric Company`s ...

Energy Technology Data Exchange (ETDEWEB)

The 66 fields discovered since the 1960s in the northern West Siberian basin contain at least 22 trillion m/sup 3/ (777 tcf) of proved gas, almost one-third of the world's reserves. Half of these fields are giants (> 85 billion m/sup 3/ or 3000 bcf of reserves). These include the largest and second-largest gas fields in the world-Urengoy (8.099 trillion m/sup 3/ or 286 tcf of gas) and Yamburg (4.81 trillion m/sup 3/ or 170 tcf of gas)-as well as most of the other ten largest gas fields in the world. The West Siberian basin occupies a 3.4-million km/sup 2/ (1.31-million mi/sup 2/) arctic lowland immediately east of the Ural Mountains, extending north under the Kara Sea. It is a composite basin, with Mesozoic-Cenozoic basin fill on top of a Paleozoic basin that overlies a crystalline Archean-Proterozoic framework. The productive zones in the northern basin are principally ...

International Nuclear Information System (INIS)

Throughout the 1990's to year 2000, energy integration, and particularly natural gas integration, was seen as a major goal in the southern cone of South America. The regional perspective for energy was related to an even more challenging objective - Latin American economic integration, which was quickly moving forward by the constitution of Mercosur, the free trade zone built by Argentina, Brazil, Uruguay and Paraguay, and also having Bolivia and Chile as special partners. Mercosur was getting stronger and becoming a successful political project. Trade conflicts existed, but they were considered normal and nobody would disagree about the viability of Mercosur. By the beginning of the 21. century, the economic integration process in South America was already advancing timidly as compared to the impetus from the beginning of 1990's. Mercosur started facing complex and almost insurmountable challenges after the numerous global financial crises ...

Energy Technology Data Exchange (ETDEWEB)

A geologic sequestration pilot in the Thornton gas field in Northern California, USA involves injection of up to 4000 tons of CO{sub 2} into a stacked gas and saline formation reservoir. Lawrence Berkeley National Laboratory (LBNL) is leading the pilot test in collaboration with Rosetta Resources, Inc. and Calpine Corporation under the auspices of the U.S. Department of Energy and California Energy Commission's WESTCARB, Regional Carbon Sequestration Partnership. The goals of the pilot include: (1) Demonstrate the feasibility of CO{sub 2} storage in saline formations representative of major geologic sinks in California; (2) Test the feasibility of Enhanced Gas Recovery associated with the early stages of a CO{sub 2} storage project in a depleting gas field; (3) Obtain site-specific information to improve capacity estimation, risk assessment, and performance prediction; (4) ...

International Nuclear Information System (INIS)

A visual study of film boiling using photographic and high speed motion-picture methods was carried out to determine the flow regime transition criteria in the post-CHF region. An idealized inverted annular flow was obtained by introducing a liquid jet of Freon 113 through a nozzle, precisely centered with respect to the internal diameter of the test section, with an annular gas flow. The respective ranges for liquid and gas exit velocities were 0.05 to 0.5 and 0.03 to 7.9 m/s. Nitrogen and helium were used in the study. For the present configuration, there are four basic flow regimes. Beginning from the nozzle exit, there is a smooth, inverted annular flow section with liquid in the core and gas in the annulus; followed by the rough wavy section with an intact liquid core, the agitated and the dispersed flow regimes. For a given liquid jet velocity, the axial extent of each flow regime decreases with ...

International Nuclear Information System (INIS)

A visual study of film boiling is carried out to determine the flow regime transition in the post-CHF region. An idealized inverted annular flow is obtained by introducing a liquid jet of Freon 113 through a nozzle, precisely centered with respect to the internal diameter of the test section, with an annular gas flow. The respective ranges for liquid and gas velocities are 0.05-0.5 and 0.03-8.2 m s"-"1. Nitrogen and helium are used in the study. For the present configuration, there are four flow regimes; namely, the smooth inverted annular flow-section, the rough wavy, agitated and dispersed flow regimes. (author).

Energy Technology Data Exchange (ETDEWEB)

As part of The International Northern Sea Route Programme (INSROP), Subprogram III, Trade and Commercial Shipping, a study has been made concerning seaborne export of liquefied petroleum gas (LPG) from the Northern Russia, especially the West Siberian fields in Tyumen. The main purpose of the total project III.0703, part 2 and this study is to evaluate the economic viability of seaborne export from this area to the European region, mainly with the use of a special ice-strengthened LPG vessel, constructed and designed for such seaborne operations. This study concentrates on both seaborne LPG transportation, the demand and supply for seaborne LPG in the world and marine transportation of LPG from the West Siberian fields. Another purpose is to see which regions are potential exporters, importers and buyers of seaborne export of LPG from Tyumen. Currently large quantities of liquefied gas are flared off at ...

International Nuclear Information System (INIS)

Full text: The surface properties of poly (tetrafluoroethylene) (PTFE) are changed by the exposure to synchrotron radiation (SR). We succeeded in controlling the wettability of the PTFE surface from hydrophobic to hydrophilic by varying the substrate temperature during the SR irradiation and found that the wettability was ascribable to microstructure and chemical composition of surface.In these previous works, oxygen atoms were found to inhabit on the hydrophobic surface of PTFE. In this study, we investigated the surface modification of PTFE from the SR exposure experiment under the O_2 gas atmosphere. The SR exposure to the PTFE sheet was carried out at beamline 6 (BL6) of the New- SUBARU. The PTFE sheet was irradiated to the white beam, ranging 50-1000 eV at BL6 at room temperature. The gas cell was mounted at the irradiation chamber. The O_2 gas pressure in the gas cell can be maintained at about ...

Energy Technology Data Exchange (ETDEWEB)

A rotary drill bit having a drill bit body and at least one trunnion projecting from the drill bit body and a rotary cutter supported on at least one radial roller bearing on the trunnion. The rolling elements of the bearing are guided on at least one axial end facing the drill bit body in an outer bearing race groove incorporated in the bore of the rotary cutter. The inner bearing race groove is formed on the trunnion for the rolling elements of the radial roller bearing. At least one filling opening is provided which extends through the drill bit body and trunnion and is essentially axially oriented having one terminal end adjacent the inner bearing race groove and at least one filler piece for sealing the opening.

Energy Technology Data Exchange (ETDEWEB)

Ceramic ball bearings of silicon nitride are used for hard disk drive (HDD) spindle motors, to increase seed, reliability and memory capacity of the HDDs. Silicon nitride ceramics have advantages of lightweight, high strength and hardness over the conventional steel for bearings, but is expensive. A new process of high cost performance has been developed for mass production of the small-size ceramic balls. The company plans to apply these bearings to higher devices, e.g., servers, for the time being, and to expand the applicable areas, e.g., common devices and other small-size motors. The ceramic bearings have been developed jointly with Koyo Seiko Co. Ltd. (translated by NEDO)

Energy Technology Data Exchange (ETDEWEB)

In a water well sunk in the Grafschaft Bentheim region of northern Germany, small volumes of methane were emitted regularly and large volumes of methane in eruptions at irregular intervals. After some extreme gas eruptions in 2002 and 2004, the Grafschaft Bentheim district government initiated a project to investigate underground conditions in the region between Nordhorn and Bad Bentheim in order to prevent potential hazards to the locals population. The main purpose of the project was to provide information on underground mechanisms as far as possible in order to develop long-term safety strategies for freshwater supply in the region. (orig.)

Energy Technology Data Exchange (ETDEWEB)

Measurements of dissolved and atmospheric nitrous oxide (N{sub 2}O) are presented for three coastal environments: (1) the central North Sea, (2) the German Bight, and (3) the Gironde estuary. The contribution of coastal regions to the oceanic emissions of atmospheric N{sub 2}O were also determined. N{sub 2}O was measured with a gas chromatograph equipped with an electron capture detector and analyzed. The surface waters of the central North Sea and the German bight were found to be near equilibrium with the overlying atmosphere, while the mean saturation in the Gironde estuary was 132%. Mean saturations in coastal regions without estuaries or upwelling phenomena were only slightly higher than in the open ocean. When estuaries and regions with upwelling are included, however, approximately 60% of the oceanic N{sub 2}O flux is attributable to coastal regions. A review of published ...

Energy Technology Data Exchange (ETDEWEB)

Based on the air pollution values typical of brown coal furnaces the paper discusses pollution abatement measures on the part of fuel engineering and flue gas technology. Fuel engineering contributes to air pollution abatement by measures such as stepped air supply, stepped fuel supply and flue gas draw-in. Flue gas technology largely relies on measures such as the SCR method using different catalytic converters, the noncatalytic reduction of nitrogen oxides, the simultaneous separation of sulfur dioxides and nitrogen oxides, and the Denox-Luvo method. The paper concludes with remarks on the RWE brown coal power plant retrofitting scheme planning to have all power plants equipped with adequate denitrification systems until the end of 1989 at the latest. (orig./PW)

International Nuclear Information System (INIS)

Pattern formation on GaAs by Ga"+ focused-ion-beam (FIB) irradiation and subsequent Cl_2 gas etching was carried out. A higher etch rate at the FIB-irradiated area compared with that not irradiated under Cl_2 gas allows pattern construction without a mask process. The degree of residual crystal damage was evaluated using photoluminescence (PL) intensity measurements. The PL intensity in the etched region was one order of magnitude stronger than that of FIB sputtering, and was several times stronger than that of Ga"+ FIB-assisted Cl_2 etching. Etch depths of the order of 100 nm, which is five times deeper than that obtained by FIB sputtering, were efficiently performed using moderate Ga"+-ion doses.

Science.gov (United States)

The purpose of this rulemaking is to amend the effluent limitations guidelines and standards for the control of discharges of certain pollutants associated with the use of synthetic-based drilling fluids (SBFs) and other non-aqueous drilling fluids in portions of the Offshore Subcategory and Cook Inlet portion of the Coastal Subcategory of the Oil and Gas Extraction Point Source Category. These proposed limitations apply to discharges or effluent generated when oil and gas wells are drilled using SBFs or other non-aqueous drilling fluids (collectively referred to simply as SBFs) in coastal and offshore regions in locations where drilling wastes may be discharged.

Energy Technology Data Exchange (ETDEWEB)

The aim of this contract is to investigate, develop, and characterize laser-assisted processing techniques utilized to produce the fine-line, thin-metal grid structures that are required to fabricate high-efficiency solar cells. During the first quarter of this contract, a comprehensive literature search was carried out in the various state-of-the-art laser-assisted techniques for metal deposition, including laser chemical vapor deposition and laser photolysis of organometallics, as well as laser-enhanced electroplating. A compact system for the experiments involving laser-assisted photolysis of gas-phase compounds was designed and constructed. The work performed in the second quarter is detailed in this report. Metal deposition experiments have been carried out utilizing laser-assisted pyrolysis of a variety of metal-bearing polymer films and metallo-organic inks spun onto silicon substrates. Laser decomposition of spun-on silver neodecanoate ...

International Nuclear Information System (INIS)

An effort to expand the irradiation mission of the Fast Flux Test Facility (FFTF) beyond testing fuels and materials for the liquid-metal reactor (LMR) program included a study of the feasibility of producing commercial quantities of "6"0Co. The "6"0Co would be produced by neutron capture in assemblies containing an array of natural cobalt pins and hydrogen-bearing moderator pins located at the periphery of the FFTF core. Adding hydrogenous material to the assemblies enhances "6"0Co production by slowing neutrons into energy ranges where the "5"9Co capture cross section is higher. Some of the moderated neutrons leak from the moderated region to adjacent fuel regions, increasing local fission rates. In order to validate calculated fission rates and establish calculational biases and uncertainties, experiments were conducted in the zero-power plutonium reactor (ZPPR) to measure fission rates in fuel ...

Science.gov (United States)

A roller bearing hot box sensor utilizing a metallic temperature sensitive elongated wire element. The wire element contacts at temperatures in the range of about 125 F to about 225 F so that when the contraction movement of the wire is attached to a conn...

UK PubMed Central (United Kingdom)

There has been great interest in understanding the methods by which collagen-based load-bearing tissue is constructed, grown and maintained in vertebrate animals. To date, the responsibility for this...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

This study presents a dynamic analysis of a flexible rotor supported by two porous squeeze couple stress fluid film journal bearings with non-linear suspension. The dynamics of the rotor center and bearing center are studied. The analysis of the rotor-bearing system is investigated under the assumptions of non-Newtonian fluid and a short bearing approximation. The spatial displacements in the horizontal and vertical directions are considered for various non-dimensional speed ratios. The dynamic equations are solved using the Runge-Kutta method. The analysis methods employed in this study is inclusive of the dynamic trajectories of the rotor center and bearing center, power spectra, Poincare maps and bifurcation diagrams. The maximum Lyapunov exponent analysis is also used to identify the onset of chaotic motion. The numerical results show that the stability of the system varies with ...

Energy Technology Data Exchange (ETDEWEB)

An experimental apparatus has been built that allows direct measurement of the oil film thickness in a bearing that is subjected to dynamic loads and shaft speeds representative of those occurring in automotive engine connecting rod, big-end bearings. Dynamic motion of the shaft, relative to the bearing, is measured as a function of shaft rotational angle, using non-contact, eddy-current probes. A computer based data acquisition system is used to measure, record, and analyze the journal position in the bearing. The test bearing is 63.5 mm in diameter by 25.4 mm long, and is loaded using a servo-hydraulic actuator rated at 98.3 kN. The journal has an operating speed of 500 to 3800 rpm. The actuator is controlled by a computer-generated waveform that can duplicate load profiles developed by various engines operating at a wide range of conditions. Measurements taken with the shaft ...

Energy Technology Data Exchange (ETDEWEB)

The stability of accretion disks against short wavelength perturbations is analyzed. The disk is shown to be unstable to slow thermal perturbations propagating in the z-direction for sufficiently high values of the stress parameter ..cap alpha.. and sufficiently low values of the ratio of gas to total pressure. The acoustic flux from the ''middle region'' of the disk is estimated and discussed.

Science.gov (United States)

... Tanzania, and the attack on the USS COLE. ... vis another has no bearing on the legality of the attack. If the person attacked is a combatant, the use of ...

Science.gov (United States)

... by the Bureau. A canvas of supply sources produced only one other, the Flexo roller bearing swivel. Accordingly, only the ...

Science.gov (United States)

roller bearing strength suffi- cient to support efficient, rolling friction movement, even in the presence of large, resisting forces. ...

Science.gov (United States)

... HARDENED CUP AND CARBURIZED AND HARDENED CORES HAVE BEEN PROFILED USING 2 TYPES OF EDDY CURRENT PROBES. ...

Energy Technology Data Exchange (ETDEWEB)

Use of gas-fired combined-cycle technology (GFCC) in the electric-utility sector could play an important role in a least-cost planning strategy and thereby provide significant benefits to the utilities and their customers. Potential benefits include reduced capital and operating costs, more-effective matching of load growth and capacity additions, greater system reliability, and reduced environmental emissions. GFCC technology was examined in eight utility systems in six geographic regions to estimate the potential benefits of its use. In all systems, GFCC technology was shown to have the potential to reduce the cumulative capital costs for adding new capacity. The overall conclusion of the study is that GFCC technology offers the potential for significant savings in many regions of the United States and that these benefits would appear over a wide range of economic conditions. The study provides insight into the important ...

International Nuclear Information System (INIS)

This paper traces the development and progress of magnetic suspension systems and magnetic bearings in the USSR. The paper describes magnetic bearings for turbomachines, magnetic suspension systems for vibration isolation, some special measuring devices, wind tunnels, and other applications. The design, principles of operation, and dynamic characteristics of the system are presented.

Energy Technology Data Exchange (ETDEWEB)

The US Environmental Protection Agency (EPA) conducted a cost-effectiveness (CE) analysis to estimate the incremental cost of complying with the proposed effluent limitation guidelines (ELGs) for the coastal oil and gas industry (EPA 1995a). EPA`s CE analysis calculates the pounds of each pollutant that would be removed if the chosen discharge option is selected. In 1993, EPA issued final ELGs for the offshore oil and gas industry and published an offshore CE analysis. The chemical characteristics of produced water from the offshore region are essentially the same as those of produced water from the coastal region. It was surprising, therefore, that EPA chose a much longer list of pollutants and generally stricter weighting factors for the coastal CE analysis. This report reviews the data, assumptions, and analyses used in EPA`s coastal CE analysis and identifies alternate data, assumptions, and ...

Energy Technology Data Exchange (ETDEWEB)

The Cambro-Ordovician platform was formed along the margin of the old super-continent of Laurentia approximately 470 million years ago, and is a prolific producer of hydrocarbons. This presentation provided a geological review of the region as well as estimates of the amounts of oil in place. A simplified geological cross-section of the formation was presented, as well as a chart of the Anticosti Basin of western Newfoundland. Details of exploration wells targeting the Cambro-Ordovician carbonate platform and current west coast land holdings were provided. An outline of the area's petroleum system included details of source rock, reservoirs, traps and seals and migration and timing. Offshore prospects for the platform were estimated to be in the region of 100 to 200 million barrels. Onshore prospects were estimated to be in the region of 30 million to 150 million barrels. It was noted that limited coverage by ...

Energy Technology Data Exchange (ETDEWEB)

Fourier transform infrared spectroscopy is a simple, fast, reliable and nondestructive analytical method. By using the method developed in Clark Atlanta University, consistent and reliable infrared spectral results can be obtained. An accurate radiant energy can be calculated from these infrared spectra by using a blackbody as the calibration standards. By means of the specially-designed-and-lab-made sampling inlet and the Horiba gas analyzers, the compositions of CO{sub 2}, CO, UCH, NOx and O{sub 2} etc. from the combustion exhaust gases have been on-line accurately analyzed. The commercial natural gas IR burner performed differently in the different conditions. For the methane-air combustion, at the equivalence ratio {Phi} = 1, the IR burner produced its maximum radiation efficiency, {approximately}31.4%, and the concentration of CO{sub 2} reached its maximum value, {approximately}10.7%. In the fuel-lean region, the O{sub ...

Energy Technology Data Exchange (ETDEWEB)

This paper describes the experimental results of long-life solid lubricated ball bearings tested under high-vacuum of 10 exp -4 Pa, high-temperature of 300 C, and high-speed (9000 rpm) conditions. For full ball-type bearings, the thin soft metals, either Ag or Pb, which were coated on the races and balls, appeared to have good torque properties. However, the durability of such bearings was less than 300 hours. The transfer films from the lamellar solid MoS2 and metal composite retainers improved the torque and wear properties. For ceramic, i.e., silicon nitride, balls used with steel rings, wear occurred on the inner rings. All ceramic bearings with composite retainers showed improved torque and wear properties. 18 refs.

International Nuclear Information System (INIS)

The helium-cooled HTGR (High Temperature Gas-cooled Reactor) will take an important position in the global energy strategy. It is expected to supply not only electricity but also high quality thermal energy for various industries and local utilities without exhausting any green house effect gas or acid rain gas. The key R and D issue of the HTGR is economical competitiveness, particularly against light water reactors. Due to the poor heat transfer of the single phase helium, the HTGR's volumetric power density is restricted to tenth of corresponding PWR's value so that increasing the power density by improving heat transfer is strongly desired. The standstill can be broken through by adopting gas-solid suspension medium. Its heat transfer performance is quite excellent. Its heat capacity can be increased drastically without excessive pressurization. Although the thermal radiation is a dominant heat ...

Energy Technology Data Exchange (ETDEWEB)

We report the direct molecular dynamics simulations for molecular ball bearings composed of fullerene molecules (C{sub 60} and C{sub 20}) and multi-walled carbon nanotubes. The comparison of friction levels indicates that fullerene ball bearings have extremely low friction (with minimal frictional forces of 5.283 x 10{sup -7} and 6.768 x 10{sup -7} nN/atom for C{sub 60} and C{sub 20} bearings) and energy dissipation (lowest dissipation per cycle of 0.013 and 0.016 meV/atom for C{sub 60} and C{sub 20} bearings). A single fullerene inside the ball bearings exhibits various motion statuses of mixed translation and rotation. The influences of the shaft's distortion on the long-ranged potential energy and normal force are discussed. The phonic dissipation mechanism leads to a non-monotonic function between the friction and the load rate for the molecular ...

Energy Technology Data Exchange (ETDEWEB)

Aiming to realize ball bearings operable in a vacuum and under high temperature, silicon nitride (Si3N4) ceramic ball bearings were tested. The tested ball bearings were angular contact ball bearings composed of silicon nitride with sputtered molybdenum disulfide coating using a retainer of hot-pressed self-lubricating composite material. The time variation of the frictional torque was examined for the operations under the conditions at 500{degree}C in a vacuum at a rotational speed of 600 rpm and 50N thrust load for 5{times}10{sup 7}revolutions (1400 hours) and for 1.5{times}10{sup 8}revolutions (4200 hours). Excellent tribological performance was obtained. The ball bearings are lubricated with the molybdenum disulfide film at the initial stage of the operation and with a transfer film formed from the retainer material to the balls. In a test at 650{degree}C, low and stable ...

International Nuclear Information System (INIS)

This study presents a dynamic analysis of a rotor supported by two turbulent flow model journal bearings and lubricated with couple stress fluid under nonlinear suspension. The dynamics of the rotor center and bearing center is studied. The dynamic equations are solved using the Runge-Kutta method. The analysis methods employed in this study is inclusive of the dynamic trajectories of the rotor center and bearing center, power spectra, Poincare maps and bifurcation diagrams. The maximum Lyapunov exponent analysis is also used to identify the onset of chaotic motion. The results show that the values of dimensionless parameters l* strongly influence dynamic motions of bearing and rotor centre. It is found that couple stress fluid improve the stability of the system when l* > 0.4 even if the flow of this system is turbulent. We also demonstrated that the dimensionless rotational speed ratios s and the ...

Energy Technology Data Exchange (ETDEWEB)

Lubricant additives have been known to affect rolling element bearing surface durability for many years. Tapered roller bearings were used in fatigue testing of lubricants formulated with gear oil type additive systems. These systems have sulfur- and phosphoruscontaining compounds used for gear protection as well as bearing lubrication. Several variations of a commercially available base additive formulation were tested having modified sulfur components. The variations represent a range of ''active'' extreme pressure (EP) chemistries. The bearing fatigue test results were compared with respect to EP formulation and test conditions. Inner ring near-surface material in selected test bearings was evaluated on two scales: the micrometer scale using optical metallography and the nanometer scale using transmission electron microscopy (TEM). Focused-ion ...

Energy Technology Data Exchange (ETDEWEB)

This report covers the period from October 1, 1992 to March 1, 1993. The overall goals of the program task are to provide a final synthesis of six deep seismic reflection profiles and other geological and geophysical data from the southern Washington Cascades region where a probable extensive deep sedimentary basin has been discovered. This deep sedimentary basin is hypothesized from geological, regional magnetotelluric (MT), gravity, magnetic , and seismic reflection data as described in the American Association of Petroleum Geologists (AAPG) article by Stanley and others (1992). This report analyzed three seismic reflection profiles acquired by the Morgantown Energy Technology Centers in combination with the extensive MT and other data to outline a probable geological model for a thick conductive section of rocks in the southern Washington Cascades (called the Southern Washington Cascades conductor, SWCC). Earlier MT models suggested that the ...

Energy Technology Data Exchange (ETDEWEB)

In the Ti-Si-C and Ti-Si-C-N systems, metastable layers were precipitated by means of non-reactive magnetron sputtering of hot-pressed two-phase TiC/SiC and TiN/SiC targets with 20 mole% and 50 mole% SiC. The preparation parameters were varied as follows: ion bombardment during precipitation (bias sputtering), substrate temperature, and annealing times when annealing amorphous 50%:50% TiC/SiC and 50%:50% TiN/SiC layers. Sputtering of targets containing 20% SiC was found to result in monophase fcc layers (NaCl structure). This was documented on the basis of X-ray and electron diffraction patterns. Direct precipitation of targets with 50 mole% SiC resulted in amorphous layers. Increasing the ion bombardment during accretion, raising the substrate temperature, and annealing amorphous 50%:50% TiC/SiC and 50%:50% TiN/SiC (layers precipitated directly) resulted in the crystallization of TiC and TiN nanocrystallites, respectively, imbedded in an amorphous SiC matrix. These crystallites were ...

CERN Document Server

Mon R2, at a distance of 830 pc, is the only ultracompact HII region (UC HII) where the photon-dominated region (PDR) between the ionized gas and the molecular cloud can be resolved with Herschel. HIFI observations of the abundant compounds 13CO, C18O, o-H2-18O, HCO+, CS, CH, and NH have been used to derive the physical and chemical conditions in the PDR, in particular the water abundance. The 13CO, C18O, o-H2-18O, HCO+ and CS observations are well described assuming that the emission is coming from a dense (n=5E6 cm-3, N(H2)>1E22 cm-2) layer of molecular gas around the UC HII. Based on our o-H2-18O observations, we estimate an o-H2O abundance of ~2E-8. This is the average ortho-water abundance in the PDR. Additional H2-18O and/or water lines are required to derive the water abundance profile. A lower density envelope (n~1E5 cm-3, N(H2)=2-5E22 cm-2) is responsible for the absorption in the NH 1_1-0_2 ...

Energy Technology Data Exchange (ETDEWEB)

The thermal analysis of a turbine stack discharging exhaust gases to the atmosphere is presented. The examined turbine stack belongs to a gas lift plant for oil extraction located in the Gulf area. The analysis has been performed because an overheating of the anchor flange/bolts and of the concrete foundation occurred and caused small cracks in the upper layer of the foundation. A qualitative thermal analysis of the stack has pointed out that the main cause of the overheating was the thermal radiation in the air-filled region underneath the stack bottom plate. Detailed calculations performed by using a CFD code (Fluent ver. 6.0.12), cross-checked with measurements taken from site, have shown that a significant reduction of the heat flux to the foundation could be obtained by filling the above mentioned air region with an insulating material. The benefits of this solution are prevailing over those achievable with the ...

Energy Technology Data Exchange (ETDEWEB)

Questions are examined of prospecting for nonanticlinical traps within North Sakhalin, their spatial distribution and evaluation of the outlook for oil and gas content. Traps of tapering and facial substitution on wings and periclines of local elevations, accumulative bar and erosion-accumulative channel are isolated. THe hypothesis is made that it is possible to form stratigraphic traps above the discrepancy and below it. It is noted that formation of zones of lithological tapering and facial substitution are associated with areas of the exchange of the sedimentation situation. The primary role of the shore and coastal zones in the formation of the examined types of nonanticlinal traps is established. The Okhino-Ekhabinskiy region in North Sakhalin is isolated as the primary object for prospecting for nonanticlinal traps.

Energy Technology Data Exchange (ETDEWEB)

In April and May of 1999 the Berkeley Gas-filled Separator was used to search for the production and decay of element 118 from the {sup 86}Kr + {sup 208}Pb reaction, according to Smolanczuk's predictions of relatively large production rates. Three decay chains, each consisting of an implanted heavy ion, followed by a rapid (ms) succession of high-energy (>10 MeV) alpha-particle decays were detected. These chains are consistent with the production and decay of element 118 with mass number 293. These results a) show experimental evidence for the existence of shell-stabilized superheavy elements, b) provide experimental values for refinement of nuclear mass models in the superheavy element region, and, most importantly, c) present a new' reaction pathway for the production of superheavy elements. (author)

Science.gov (United States)

This paper discusses the mechanisms of gas breakdown at low values of pressure and inter-electrode gap, i.e. in the vicinity of the Paschen minimum. In this area of pressure and inter-electrode gap values, breakdown occurs either through gas or vacuum mechanisms, and also the so called anomalous Paschen effect appears. Electrical breakdown of electropositive, electronegative and noble gases has been investigated theoretically, experimentally and numerically. Based on the results obtained, regions in which particular breakdown mechanisms appear have been demarcated. Special attention has been devoted to the anomalous Paschen effect as well as to the avalanche vacuum breakdown mechanism.

Energy Technology Data Exchange (ETDEWEB)

Operation and maintenance cost estimating methodologies for advanced coal-fired atmospheric circulating fluidized-bed and advanced natural gas-fired combined cycle electric power plants are presented. The purpose of these cost estimating relationships is for use in long range planning and evaluation of the economics of use of these technologies for electric power generation. Projected annual costs of reference plants at ten different sites in the United States, one in each of the ten DOE regions, are given as of 1989, and comparisons are made with existing technologies. A listing of a computer program implementing the methodologies is included. 14 refs., 4 figs., 13 tabs.

Energy Technology Data Exchange (ETDEWEB)

Process engineers can predict quickly and accurately the equilibrium behavior of simultaneous H/sub 2/S and CO/sub 2/ absorptions in monoethanolamine and diethanolamine systems by using the nomographs developed by H.K. Ferguson Co. Correlation lines for temperature and amine concentration provided with the loading curves make the nomographs useful for any combination of temperature, concentration, and liquid loadings. The accuracy of the nomographs is within the acceptable range for normal engineering applications when the operating parameters lie in the region of practical gas-treating conditions. Correction curves given for each nomograph to improve the accuracy are generally not needed except for cases where the gas loadings are higher than 0.5 mole/mole of amine.

Energy Technology Data Exchange (ETDEWEB)

A multi-zone computational model in conjunction with some engine tests are used to examine the combustion process of gas fueled diesel engines commonly known as dual fuel engine to provide information about details of the production of exhaust emissions, especially at light load when very lean mixtures are employed. Detailed chemical reaction kinetic simulation is employed for each of these individual combustion zones so as to establish the associated temporal variations in the concentrations of reacting species right to the exhaust stage. The influence of changes in major operating and design parameters such as the concentration of the gaseous fuel in the cylinder charge, intake temperature and the size of the diesel pilot fuel employed on the production of the exhaust emissions are examined. It is demonstrated in general that any measure that tends to increase the size of the combustion regions within the overly lean cylinder charge will ...

Energy Technology Data Exchange (ETDEWEB)

Aerospace gas turbine disks operate in an environment of relatively high stresses caused by centrifugal forces and elevated temperatures. These severe conditions necessitate the need for materials with high temperature strength and good low cycle fatigue resistance. One class of alloys used for this task is the nickel base superalloys, out of which, IN 718 is the most widely used in the aerospace industry. The properties of IN 718 are attributed to the combined effects of the chemistry, heat treatment, and microstructure. The chemistry is tailored not only for solid solution strengthening but also for precipitation hardening developed during heat treatment, which combined with a fine grained microstructure lead to excellent mechanical properties such as low cycle fatigue resistance and elevated temperature strength. The properties of a gas turbine disk are sensitive to the microstructure, in particular the grain size, which is dependent on the ...

Energy Technology Data Exchange (ETDEWEB)

The necessary conditions to design the methanol-fueled direct injection diesel engine with a reservoir type glow plug were cleared up from the points of view to prevent the air contamination and to use as an alternative oil for automotives, and as a result the good engine performance and emission characteristics could be obtained under the wide operating condition. The following facts were clarified: It is necessary to arrange the glow plug on the line of atomizing axis near the nozzle hole to ensure the ignitability under a wide operating condition. The reservoir type glow plug which reserves the premixed gas around the glow plug can shorten the ignition delay time and improve the combustion stability and the net thermal efficiency in the light load region. The combustion in the light load region was accelerated, NO{sub x} emission rate was suppressed and moreover, the net thermal efficiency and catalyst conversion rate ...

Science.gov (United States)

Plasma generated in low-density vapor by a negative ion beam has been studied experimentally and computationally. We show that space charge neutralization of the beam occurs at very low vapor density, and that correspondingly the electron density may be much less than the beam and plasma ion densities. When there is a large local gas density, as in a charge changing cell, the resulting high electron density is also localized to the same region. Therefore, very few electrons will reach a negative ion accelerator even if it is placed one or two beam diameters from such a cell.

Science.gov (United States)

The entrainment flow rate distribution, the gas velocity profile, and the concentration profile of droplets across the channel cross section in fully developed region of a horizontal rectangular channel of 150mm width and 50mm height were measured. The concentration profile of droplets was expressed by a simple equation based on a constant diffusion coefficient model. From this equation the effects of gravity and turbulent diffusion of droplets on the concentration profile were evaluated. The characteristic mean settling velocity of a group of droplets with various diameters was derived, and using this value the mean diffusion coefficient of the group of droplets was obtained

Energy Technology Data Exchange (ETDEWEB)

Many mining regions in the United States contain extensive areas of flooded underground mines. The water within these mines represents a significant and widespread opportunity for extracting low-grade, geothermal energy. Based on current energy prices, geothermal heat pump systems using mine water could reduce the annual costs for heating to over 70 percent compared to conventional heating methods (natural gas or heating oil). These same systems could reduce annual cooling costs by up to 50 percent over standard air conditioning in many areas of the country. (Formatted full-text version is released by permission of publisher)

Energy Technology Data Exchange (ETDEWEB)

Ball screw bearings are used for the fine control of Control Rod Drive Mechanism (CEDM) for the SMART-P. Because the friction coefficient of the ball screw bearings suddenly increases at the limit temperature of 120 .deg. C, the surrounding temperature of the ball screw bearings should be less than the limit temperature for the functional integrity of the CEDM. The CEDM coolers are installed at the lower portion of the ball screw bearings to maintain the bearings' temperature less than the limit. In order to check the CEDM cooler satisfy the temperature limit of ball screw bearing at the possible operational conditions, the cooling capacity of the CEDM coolers, which was determined at the stage of 'conceptual design', is evaluated using the Computational Fluid Dynamics(CFD) code, Fluent. The analysis result shows that the current CEDM ...

Energy Technology Data Exchange (ETDEWEB)

BC Hydro recently conducted a demonstration test of a bearing condition monitor. The test, at the 529-MW Kootenay Canal project, proved the ability of the monitor to detect machine condition faults. The capability to detect changing conditions during normal operation of hydroelectric machines gives hydro plant owners the opportunity to anticipate needed maintenance and ultimately to reduce the number of equipment failures. BC Hydro intends to install bearing condition monitors, as well as windings monitors, brushgear monitors, environmental monitors, and other selected systems in as many as 46 of its hydro generators. BC Hydro analyzed forced outages between 1985 and 1989 in its hydro system to identify which parts of a generating unit resulted in the highest number of hours of outage. From there, the utility has formulated a concept for a machine condition monitoring system. To keep the system cost effective, it will be developed in modules. ...

International Nuclear Information System (INIS)

Extensive investigations and detailed analysis of the failure reason of 9DVN002ZV fan in Daya Bay Nuclear Power Station showed that the fan destroy was caused by the failure of non-drive end bear. The direct cause of this bearing' failure was its improper assembly caused by improper maintenance procedure, and the root cause was too small internal radial clearance after mounting. The factor affecting bearing internal radial clearance, the relationship between clearance and operating life time and fan failure process were discussed. (authors)

Energy Technology Data Exchange (ETDEWEB)

A new phenylboric acid derivative entrapped lipiodol (PBAD-lipiodol) was developed as a boron carrier for the boron neutron capture therapy (BNCT) of hepatoma in Taiwan. The biodistribution of both PBAD-lipiodol and BPA-fructose was assayed in GP7TB hepatoma-bearing rat model. The highest uptake of PBAD-lipiodol was found at 2 h post injection. The application of BNCT for the hepatoma treatment in tumor-bearing rats is suggested to be 2-4 h post PBAD-lipiodol injection.

CERN Document Server

Ultra-luminous infrared galaxies are among the most luminous objects in the local universe and are thought to be powered by intense star formation. It has been shown that in these objects the rotational spectral lines of molecular hydrogen observed at mid-infrared wavelengths are not affected by dust obscuration, leaving unresolved the source of excitation of this emission. Here I report an analysis of archival Spitzer Space Telescope data on ultra-luminous infrared galaxies and demonstrate that star formation regions are buried inside optically thick clouds of gas and dust, so that dust obscuration affects star-formation indicators but not molecular hydrogen. I thereby establish that the emission of H_2 is not co-spatial with the buried starburst activity and originates outside the obscured regions. This is rather surprising in light of the standard view that H_2 emission is directly associated with star-formation ...

Energy Technology Data Exchange (ETDEWEB)

Extensive experimental investigation has been carried out on used flight bearings of the high pressure oxidizer turbopumps (HPOTP) of the space shuttle main engine (SSME) in order to determine the dominant wear modes, their extent, and causes. The paper presents the methodology, various surface analysis techniques used, results, and discussion. The mode largely responsible for premature bearing wear has been identified as adhesive/shear peeling of the upper layers of bearing balls and rings. This mode relies upon the mechanisms of scale formation, breakdown, and removal, all of which are greatly enhanced by the heavy oxidation environment of the HPOTP. Major causes of the high wear rates appear to be lubrication and cooling, both inadequate for the imposed conditions of operation. Numerous illustrations and evidence are provided. 22 refs.

Energy Technology Data Exchange (ETDEWEB)

Recent progress in yttrium-based oxide high-temperature superconductors has enabled the production of a large diameter bulk with a strong flux-pinning force. A combination of this superconductor and a permanent magnet makes it feasible to fabricate a noncontact, non-controlled superconducting magnetic bearing with a very small rotational loss, applicable to a flywheel energy storage system. A conceptual design of an 8 MWh flywheel energy storage system using the new bearing has been developed, based on measured data on a miniature bearing model, which proved to be potentially capable of achieving a high energy storage efficiency of 84 pc. A 100 W h-class experimental system was then built, which attained a high revolution rate of 17000 rpm, with a rotational loss of about 0.6 W. (authors). 2 refs., 7 figs., 3 tabs.

British Library Electronic Table of Contents (United Kingdom)

Roller bearing is one of the most widely used elements in rotary machines. Condition monitoring of such elements is conceived as pattern recognition problem. Pattern recognition has three main phases: feature extraction, feature selection and feature classification. Histogram features can be used for fault diagnosis of roller bearing. This paper presents the use of decision tree for selecting best few histogram features (bin ranges) that will discriminate the fault conditions of the bearing from given train samples. These features are extracted from vibration signals. A rule set is formed from the extracted features and fed to a fuzzy classifier. The rule set necessary for building the fuzzy classifier is obtained largely by intuition and domain knowledge. This paper also presents the usag...

Energy Technology Data Exchange (ETDEWEB)

Conversion of Idaho National Engineering and Environmental Laboratory radioactive sodium-bearing waste into a single solid waste form by evaporation was demonstrated in both flask-scale and pilot-scale agitated thin film evaporator tests. A sodium-bearing waste simulant was adjusted to represent an evaporator feed in which the acid from the distillate is concentrated, neutralized, and recycled back through the evaporator. The advantage to this flowsheet is that a single remote-handled transuranic waste form is produced in the evaporator bottoms without the generation of any low-level mixed secondary waste. However, use of a recycle flowsheet in sodium-bearing waste evaporation results in a 50% increase in remote-handled transuranic volume in comparison to a non-recycle flowsheet.

Energy Technology Data Exchange (ETDEWEB)

With an objective to detect gas leaking from an underground gas pipeline, discussions have been given on a method which utilizes acoustic characteristics of leakage. On leaking sound generated from damaged portions, the form of damaging was hypothesized as pinholes, and spectra of leaking sounds from holes with different diameters were measured. The dominant frequency decreases as the hole diameter increases, while it is in a region of relatively high frequency of 1 kHz or higher. However, detection from the ground surface was impossible when cover soil has thickness from 0.5 to 1.5 m. In an experiment to measure leaking sound inside the pipe, pressure in the pipe was adjusted to 0.02 atm which is a standard pressure for a low-pressure pipe, and the sound was measured when the hole diameters were varied. In any of the results obtained by varying the hole diameter, spectra having the dominant frequency in the ...

International Nuclear Information System (INIS)

The paper presents the investigations of plasma streams generated by pulsed plasma gun 'Prosvet' operated with different gases: krypton (m=84) and helium (m=4). Contour parameters of working gas spectral lines (full intensities and half-widths) are used for determination of spatial distributions of the electron density and temperature. Temporal distributions of the spectral lines intensities (both neutrals and ions of working gas), impurity spectral lines and continuum intensities are analyzed. Plasma stream velocity was estimated by time-of-flight method between two monochromators (MUM) connected with photo-multiplier. longitudinal distributions of the plasma pressure for different time moments and varied distances from the accelerator output have been used for investigation of the plasma stream dynamics and study the plasma compression in the focus region for different operational regimes of plasma accelerator. ...

Energy Technology Data Exchange (ETDEWEB)

The information reported is for the period October I to December 31, 1993. During this quarter, activities were undertaken in Task 2. Oxygen concentrations were measured in the post-flame region of the entrained flow reactor. The sampling probe was used for the hot gas tests to sample the gas stream. Samples were injected into a gas chromatograph to determine the oxygen concentration. Results agreed with thermoequilibrium calculations that yield equilibrium compositions based on the stoichiometry of the feed gases. The axial temperature distribution along the reactor centerline was measured using a silica-coated platinum-rhodium thermocouple. Two coating techniques were tested and it was found that flame-plating silica to the thermocouple wires produced a thinner coating than a ceramic adhesive technique and therefore a smaller radiation correction. Other activities this quarter included the fabrication ...

Energy Technology Data Exchange (ETDEWEB)

A geochemical survey to assess and evaluate the Devonian oil shale resources of north Alabama, northwest Georgia, and south-central Tennessee has been performed. Information is provided on the location and extent of the more favorable kerogen-bearing Devonian shale, oil and uranium content of the shale, trace metal and standard rock analyses for shale, data on the physical properties of the shale rock, mineralogy of the shale, chemical properties of the oil, and other pertinent data deemed necessary for resource development. The results indicate that the oil yield from areas underlain by Chattanooga Shale can be divided into areas having greater than 7 g/t and areas having less than 7 g/t. In general, the oil yield by Fischer assay of samples from the folded Appalachian Valley and Ridge and the Appalachian Plateaus provinces is poor, all having less than 5 g/t and most samples closer to 0 g/t. The extreme variance of Fischer assay values in the Chattanooga Shale ...

Energy Technology Data Exchange (ETDEWEB)

In the design of natural gas compressor stations, a check valve is a critical element which is commonly placed on the discharge side of the compressor to prevent reverse flow that can cause serious damage to the compressor itself and other components such as seals and bearings. One of the selection criteria of the check valve for this particular application is the valve flow characteristics in steady flow, and its dynamic characteristics in unsteady flow operation. With regards to steady flow valve characteristics, current models for the determination of the check valve open angle vs. mean flow velocity are based on semi-empirical data obtained from water tests, which were found to deviate from measurements in compressible flows. This paper presents results of steady compressible flow testing of an NPS 4 swing type check valve in air. Mean flow velocities vs. disc angles were measured together with several local pressure measurements at the ...

Energy Technology Data Exchange (ETDEWEB)

The Sunniland Limestone (Lower Cretaceous), consisting of carbonate rock and anhydrite, bears the only oil and gas production in southern Florida. Raccoon Point field, Collier County, Florida, is one of 13 fields discovered along the Sunniland producing trend, producing from paleotopographic highs associated with shelfal patch reefs and high-energy bioclastic deposits. Deposition of the Sunniland Limestone, as determined from detailed stratigraphic and microfacies analysis (using core, thin sections, and well logs), occurred in three transgressive-regressive packages or sequences: the lower, middle, and upper Sunniland. Each sequence is further divided into successive shallowing-upward intervals or parasequences. The dolomite reservoirs at Raccoon Point field occur at the top of the middle Sunniland and within the upper Sunniland. They are interpreted as high-energy deposits formed from bioclastic debris and as a network between rudist mounds. ...

Energy Technology Data Exchange (ETDEWEB)

The aims of the work described here were to provide an experimental basis for evaluating the committed effective dose equivalent per unit intake together with the ALI for four industrial oxide bearing dusts, and to assess the extent to which {sup 241}Am could be used for estimating the {sup 239}Pu content of the lung after an accidental intake of these materials. (author).

Energy Technology Data Exchange (ETDEWEB)

A phantom simulation imaging quality control device is described that effectively simulates one centimeter lesions, using steel ball bearings as gamma ray attenuators. The bearings are mounted in a synthetic resinous sheet in an orthogonal pattern. The phantom can provide uniformity, resolution, linearity, distortion and field size checks, all with a single exposure.

Science.gov (United States)

An analysis of the diagnosis of loading and service dependability of a rail-mounted excavator used in surface lignite mining is described. Wheel power vibrations in electric motor bearings and electric motor input bearings to the gearbox were measured in situ, in horizontal, vertical, and axial directions. The data were analyzed using a mathematical relationship. The results are presented in a loading diagram that shows the deterioration and the acceptable lower bound of machine conditions over time. Work is continuing. 5 refs., 1 fig.

Energy Technology Data Exchange (ETDEWEB)

The Coal Fired Combined Cycle (CFCC) is the unique powerplant concept developed under the leadership of the General Electric Company to provide a direct coal-burning gas turbine and steam turbine combined cycle powerplant. On the basis of previous studies and confirming work under this contract, General Electric continues to believe that the CFCC approach offers important advantages over alternate approaches: higher powerplant efficiency in the combustor temperature range of interest; reduced combustor/steam generator corrosion potential, due to low fluid-bed tube temperature (as contrasted to the air in tube cycle); and increased gas turbine bucket life from improved material protection systems. The objective of this program is to evaluate the coal fired combined cycle powerplant conceptual design, and to conduct a supporting development program. The supporting development is required for evaluating the pressurized fluidized bed combustion ...

Science.gov (United States)

Under support from the French Space Agency (CNES), a 3D+t dusty-gas model of Comet 67P/Churyumov-Gerasimenko is being developed, to compute, from the first 2014 Rosetta orbital data, the aerodynamic forces exerted on the Rosetta orbiter and on the descent lander. We report the recently developed dust dynamics part of the code. The multi-species (presently H2O and CO) gas code is optimized in terms of computational speed owing to the use of two complementary methods: (a) 3D+t Direct Simulation Monte Carlo (DSMC) runs in the non-equilibrium regions adjacent to the surface and very distant from it, and (b) solutions of the Navier-Stokes equations in-between. The model is used presently using Lamy et al. (Space Sci. Rev., 2007, 128, 23) coarse information on 67P nucleus shape and rotation, and a range of possible gas production rates Q for the early Rosetta observations at rh 3 AU (Q 1026 - 1027 s-1). In ...

Science.gov (United States)

We present a new approach for growing Si nanowires directly from a silicon substrate, without the use of a metal catalyst, silicon vapor or CVD gasses. The growth can be performed in a furnace type configuration at moderate temperatures or in localized regions by resistive heating. Since the silicon wires grow directly from the silicon substrate, they do not need to be manipulated nor aligned for subsequent applications. Wires in the 20-50 nm diameter range with lengths over 80 ?m can be grown by this technique. We have studied the effects of various growth parameters, including temperature, substrate orientation, initial sample cleaning and carrier gasses. Results indicate that most important parameters in the growth of the nanowires are the surface cleaning, the temperature and the type of carrier gas used. A model is proposed, which involves an oxide catalyst for the process, with the growth of the nanowires enabled by a significantly ...

Science.gov (United States)

The first sediments to onlap the metamorphosed Precambrian Arabian shield were Infracambrian (Proterozoic) to Middle Cambrian carbonates, clastics, and evaporites. The oldest Arabian reservoir rocks occur in the Precambrian to lower Paleozoic Era Salt of the Huqf Group, which forms the Birba field of Oman. The Middle Cambrian sequence was followed by Late Cambrian through Early Permian marine sandstones and continental to littoral siltstones and variegated shales. The first commercial oil discovered in the Arabian Gulf region occurs in fluvial sands of the Ordovician to Permian Haima and Haushi Groups of the Marmul field in south Oman. These strata are also productive in other fields and are sealed by unconformable contact with the Al Khlata Formation or beneath shale of the Albian Nahr Umr Formation. The deeply buried kerogen sediments of the Huqf Group to the southeast are believed to be the source rocks for these fields of south Oman. The Late Permian to ...

Energy Technology Data Exchange (ETDEWEB)

This paper presents the characteristics of selected parameters of organic matter of the Tertiary coal samples and organic matter of Carboniferous rock samples from the Spitsbergen. The coal samples were taken from Central Coal Basin (the Longyearbyen region) and from the Forlandsundet Basin (Oscar II Land, the Kaffioyra region). Samples of dispersed organic matter were collected from Suffolk Pynten and Sergeijevfjellet area in Sorkapp Land. The optical properties of coal samples are different from properties of dispersed organic matter. Macerals of vitrinite group dominate in all of the samples. The average content of vitrinite group macerals is much lower in dipersed organic matter samples than it is in coals. The average content of liptinite group macerals is a little lower, and inertinite group macerals is much higher. The average content of mineral matter is higher in organic matter samples than in coal samples. The average value of ...

CERN Document Server

We report the arcsecond resolution SMA observations of the $^{12}$CO (2-1) transition in the massive cluster forming region G10.6-0.4. In these observations, the high velocity $^{12}$CO emission is resolved into individual outflow systems, which have a typical size scale of a few arcseconds. These molecular outflows are energetic, and are interacting with the ambient molecular gas. By inspecting the shock signatures traced by CH$_{3}$OH, SiO, and HCN emissions, we suggest that abundant star formation activities are distributed over the entire 0.5 pc scale dense molecular envelope. The star formation efficiency over one global free-fall timescale (of the 0.5 pc molecular envelope, $\\sim$10$^{5}$ years) is about a few percent. The total energy feedback of these high velocity outflows is higher than 10$^{47}$ erg, which is comparable to the total kinetic energy in the rotational motion of the dense molecular envelope. From order-of-magnitude ...

International Nuclear Information System (INIS)

Low pressure silane plasmas are known for their ability to synthesize silicon nanoparticles via gas phase nucleation. While in the past this particle formation has often been considered from the viewpoint of a contamination problem in semiconductor processing, we here describe a silane low pressure plasma that enables the synthesis of highly oriented, cubic-shaped silicon nanocrystals with a rather monodisperse size distribution. These silicon nanocubes have successfully been used in the manufacture of single nanoparticle vertical transistors. We discuss the advantages of this new paradigm of building nanoelectronic devices. The plasma synthesis process is characterized in more detail than in prior work. The particle nucleation, growth and shape evolution are studied. Results indicate that the process provides two spatially distinct zones: a diffuse plasma for particle growth and a constricted plasma zone for particle annealing. Measurements of the plasma ion ...

Energy Technology Data Exchange (ETDEWEB)

A gene designated BRCA1, implicated in the susceptibility to early-onset familial breast cancer, has recently been localized to chromosome 17q12-q21. To date, the order of DNA markers mapped within this region has been based on genetic linkage analysis. The authors report the use of multicolor fluorescence in situ hybridization to establish a physically based map of five polymorphic DNA markers and 10 cloned genes spanning this region. Three cosmid clones and Alu-PCR-Generated products derived from 12 yeast artificial chromosome clones representing each of these markers were used in two-color mapping experiments to determine an initial proximity of markers relative to each other on metaphase chromosomes. Interphase mapping was then employed to determine the order and orientation of closely spaced loci by direct visualization of fluorescent signals following hybridization of three probes, each detected in a different color. Statistical analysis ...

Energy Technology Data Exchange (ETDEWEB)

The ventilation performance of cold-air distribution systems was investigated in a full-scale test room for three different designs of ceiling-mounted diffusers: a large square radial, a small square radial, and two linear diffusers. The supply air temperature was 38 F (3.3 C). Tests were conducted with internal heat loads and with and without furnishings. The local mean ages of air, air diffusion effectiveness, and contaminant-removal efficiency were measured using tracer gas techniques to assess the performance of the ventilation system in maintaining adequate air quality conditions in the occupied region. Air velocities and temperatures were also measured in the occupied region to calculate the air diffusion performance index (ADPI). It was found that the cold-air distribution system provided satisfactory air quality and thermal comfort conditions to the occupied region of the room. It was also found ...

Energy Technology Data Exchange (ETDEWEB)

Sputter-deposited tantalum (Ta) and reactively sputter-deposited Ta-nitride films were studied with respect to the passivation capability against copper (Cu) oxidation in thermal O{sub 2} ambient. A 200 {angstrom} Ta or Ta-nitride film was sputter-deposited on a 2,000 {angstrom} Cu film using a Ta target in an Ar/N{sub 2} gas mixture. With Ta passivation, Cu was not oxidized at temperatures up to 400 C, which can be further improved by using passivation of an amorphous Ta-nitride film deposited in an appropriate condition. The absence of long-range defects in the Ta-nitride film was presumably responsible for this improvement. However, sputtering-induced surface damage by excess N{sub 2} in the sputter gas mixture may reduce the passivation capability of Ta-nitride films. When the passivated Cu was oxidized, the Cu oxides always resided in the top surface region. That is, in the oxidation process, Cu diffused through the ...

International Nuclear Information System (INIS)

Turbulent heat transfer performance of a fuel rod with three-dimensional trapezoidal spacer ribs for high temperature gas-cooled reactors was studied for various Reynolds numbers using an annular channel at the same coolant condition as the reactor operation, maximum outlet temperature of 1000 C and pressure of 4 MPa, and analytically by a numerical simulation using the k-#epsilon# turbulence model. The turbulent heat transfer coefficients of the fuel rod were 18-80% higher than those of a concentric smooth annulus at a region of Reynolds number exceeding 2000. On the other hand, the predicted average Nusselt number of the fuel rod agreed well with the empirical correlation obtained from the experimental data within a relative error of 10% with Reynolds number of more than 5000. It was verified that the numerical analysis results had sufficient accuracy. Furthermore, the numerical prediction could clarify quantitatively the effects of the heat ...

Energy Technology Data Exchange (ETDEWEB)

The paper reports a work-in-progress outlook of a R and D project aimed at developing an advanced boiler for the combustion of virgin and exhaust olive husks at small scale. Fluidized bed technology has been preferred because of its well known advantages that include large thermal inertia, high combustion efficiency, low NOx emissions and considerable heat transfer rate. A 100 kW atmospheric bubbling fluidized bed combustor has been designed and built. The facility is equipped with devices for continuous fuel feeding as well as heat extraction from the bed region. Measurements of temperature and gas concentrations are obtained by using thermocouples and gas-analyzer. Steady state tests of combustion were carried out at typical fluidized bed combustion temperatures. Tests proved that not only exhaust olive husks but also the virgin ones - with a water content larger than 50% by mass - can be reliably fed onto the fluidized ...

Energy Technology Data Exchange (ETDEWEB)

This report describes the preliminary thermalhydraulic analysis of HTR-10 steady state full power initial core to provide a benchmark calculation of VHTGR(Very High-Temperature Gas-Cooled Reactors) safety analysis code of GAMMA(GAs Multicomponent Mixture Analysis). The input data of GAMMA code are produced for the models of fluid block, wall block, radiation heat transfer and each component material properties in HTR-10 reactor. The temperature and flow distributions of HTR-10 steady state 10 MW{sub th} full power initial core are calculated by GAMMA code with boundary conditions of total reactor inlet flow rate of 4.32 kg/s, inlet temperature of 250 .deg. C, inlet pressure of 3 MPa, outlet pressure of 2.992 MPa and the fixed temperature at RCCS water cooling tube of 50 .deg C. The calculation results are compared with the measured solid material temperatures at 22 fixed instrumentation positions in HTR-10. The wall temperature distribution in ...

Energy Technology Data Exchange (ETDEWEB)

In many regions of the world, flooded mines are a potentially cost-effective option for heating and cooling using geothermal heat pump systems. For example, a single coal seam in Pennsylvania, West Virginia, and Ohio contains 5.1 x 1012 L of water. The growing volume of water discharging from this one coal seam totals 380,000 L/min, which could theoretically heat and cool 20,000 homes. Using the water stored in the mines would conservatively extend this option to an order of magnitude more sites. Based on current energy prices, geothermal heat pump systems using mine water could reduce annual costs for heating by 67% and cooling by 50% over conventional methods (natural gas or heating oil and standard air conditioning).

Science.gov (United States)

We show that accretion disks, both in the subcritical and supercritical accretion rate regime, may exhibit significant amplitude luminosity oscillations. The luminosity time behavior has been obtained by performing a set of time-dependent 2D SPH simulations of accretion disks with different values of ? and accretion rate. An explanation of this luminosity behavior is proposed in terms of limit-cycle instability: the disk oscillates between a radiation pressure dominated configuration (with a high luminosity value) and a gas pressure dominated one (with a low luminosity value). The origin of this instability is the difference between the heat produced by viscosity and the energy emitted as radiation from the disk surface (the well-known thermal instability mechanism). We support this hypothesis showing that the limit-cycle behavior produces a sequence of collapsing and refilling states of the innermost disk region.

Energy Technology Data Exchange (ETDEWEB)

This report provides a brief summary of the milestone for Quarter 1 of 2006 of the NATional CARBon Sequestration Database and Geographic Information System (NATCARB) This milestone assigns consistent symbology to the ''National CO{sub 2} Facilities'' GIS layer on the NATCARB website. As a default, CO{sub 2} sources provided by the Regional Carbon Sequestration Partnerships and the National Group are now all one symbol type. In addition for sinks such as oil and gas fields where data is drawn from multiple partnerships, the symbology is given a single color. All these modifications are accomplished as the layer is passed through the national portal (www.natcarb.org). This documentation is sent to National Energy Technology Laboratory (NETL) as a Topical Report and will be included in the next Annual Report.

International Nuclear Information System (INIS)

Plant Assessment Technology (PAT) group, in association with Intelligent System (IS) Group and Engineering Services Department of Malaysian Institute for Nuclear Technology Research (MINT) has developed gamma scanning facilities for on-line investigation of industrial process columns and vessels. The technology, based on the principle of gamma-ray absorption, has been successfully applied for troubleshooting of a number of distillation columns and process vessels in petroleum refineries, gas processing plants and chemical plants in the country and the region. This paper outlines basic characteristics of the system and describes the inspection procedures, and in addition, case studies are also presented. The case studies are purposely chosen to illustrate the versatility of the technology, and furthermore to demonstrate the economic benefits which can be realised from the application of this technology. (author)

Energy Technology Data Exchange (ETDEWEB)

Arsenic and hydrogen ions produced from a mixture of arsine and hydrogen gas were implanted with a dose of 3 x 10{sup 15} As{sup +} ions/cm{sup 2} into silicon using an ion-shower implanter. The dominant ionic species implanted into the silicon were As{sub 2}H{sup +}, AsH{sup +}, H{sub 5}{sup +}, and H{sub 3}{sup +} ions. Arsenic atoms diffused into the silicon with large diffusion coefficients during annealing at 700 and 800 C. However, when the implanted silicon was annealed at 900 C, the arsenic atoms diffused into a deeper region in the silicon with a very small diffusion coefficient that was independent of concentration. (Abstract Copyright [2003], Wiley Periodicals, Inc.)

International Nuclear Information System (INIS)

This paper describes the heat transfer augmentation and flow situation around a single spacer (a circular cylinder) on a heated surface in a parallel plate duct in order to examine basically the effects of the spacer in the fuel elements of a High Temperature Gas-cooled Reactor. A thermosensitive liquid crystal film was used to clarify the effective region of the heat transfer. The mean Nusselt number, which was estimated within arbitrary distance from the spacer to the downstream direction, took a peak at the dimensionless distance X/D = 1 #approx# 3, and after that decreased gradually with flow direction. How heat transfer corresponds to the flow situation is also examined. The horseshoe vortex, produced around the spacer, affects the wake and contributes to the increase of the local heat transfer. (author).

Energy Technology Data Exchange (ETDEWEB)

Several components of high-temperature reactor units have roller bearings in order to carry out their motions without much friction. The use of such bearings poses friction and wear problems which cannot be mastered by commercial roller bearing technology. Possible improvements of coating, cage design and bearing materials as well as of their parameters were registered and studied. The service life of dry lubricated bearings was considerably improved. With a radial or axial load on the bearing of {>=} 10% of the static load, {approx_equal} 20x10{sup 6} rolling motions/actuations can be performed. The connections between surface compression and wear were determined, and optimum conditions for the transfer of lubricants from the cage onto the bearing race were worked out. Coating of corrosion-resistant roller bearing ...

Energy Technology Data Exchange (ETDEWEB)

This report describes the geology of the following 5 Alberta Foothills/Mountains coal zones: the Kootenay, Gething, Gates, Brazeau and Coalspur coal zones. The coal areas were assessed for gas content and compared with previous coalbed methane (CBM) exploration in the area. The coal zones can be divided into shallow (less than 1000 m depth) and deep (greater than 1000 m depth) coal zones for evaluation purposes. The potential gas content of the shallow coal zones is approximately 31 Tcf of CBM. This is considered an inferred, initial, in-place, CBM resource estimate based on limited data. The gas content of deep zones is approximately 99 Tcf of in-place CBM gas. Therefore, the total ultimate CBM resource is estimated at 130 Tcf. CBM recovery is not usually attempted due to high drilling costs and low permeability. The only CBM production from the Foothills has been from the southern Alberta Kootenay ...

Energy Technology Data Exchange (ETDEWEB)

Climate change is no longer questioned. Meeting growing global energy needs - while limiting the rate of climate change over the long term - will require both developed and developing countries to move to fuels with lower emissions of greenhouse gases and to adopt more energy-efficient technologies. Investment decisions made today will be pivotal in determining the path of global energy consumption for decades to come. Energy markets, financial markets, and the markets in which greenhouse gas emissions are traded - the so-called 'carbon markets' - together determine which technologies are adopted, and how quickly. Over the next half-century, energy demand will grow almost four times as rapidly in developing countries as in developed countries. Consequently, finding ways to increase investment in cleaner energy technologies in rapidly-growing economies in the developing world will be an essential component of global efforts to alter the path of ...

Energy Technology Data Exchange (ETDEWEB)

This fourteenth quarterly technical progress report of the MHD Integrated Topping Cycle Project presents the accomplishments during the period November 1, 1990 to January 31, 1991. Testing of the High Pressure Cooling Subsystem electrical isolator was completed. The PEEK material successfully passed the high temperature, high pressure duration tests (50 hours). The Combustion Subsystem drawings were CADAM released. The procurement process is in progress. An equipment specification and RFP were prepared for the new Low Pressure Cooling System (LPCS) and released for quotation. Work has been conducted on confirmation tests leading to final gas-side designs and studies to assist in channel fabrication.The final cathode gas-side design and the proposed gas-side designs of the anode and sidewall are presented. Anode confirmation tests and related analyses of anode wear mechanisms used in the selection of the proposed anode ...

International Nuclear Information System (INIS)

Greenhouse gas emissions from international maritime transport are exempt from liabilities under the Kyoto Protocol. Research into quantifying these emissions is ongoing, and influences policy proposals to reduce emissions. This paper presents a cargo-based analysis of fuel consumption and greenhouse gas emissions from New Zealand's international maritime transport of goods. Maritime transport moves 99.5% (by mass) of New Zealand's internationally traded products. It is estimated that 73% of visiting vessels' activity can be directly attributed to the movement of goods in and out of New Zealand. A cargo-based methodology was used to estimate that the international maritime transport of New Zealand's imports and exports consumed 2.5 million tonnes (Mt; 2.6 billion litres) of fuel during the year 2007, which generated 7.7 Mt of carbon dioxide (CO_2) emissions. Double-counting of emissions would occur if a similar method was applied to all New ...

Energy Technology Data Exchange (ETDEWEB)

The lateral bearing device is made of 7 lateral supports, each positioned to allow the displacement of the steam generator due to thermal or seismic effects. Each support includes a buffer plate that can be positioned on the steam generator using a position control assembly. This control assembly consists of a screw jack arrangement where the nut is fastened via an energy absorbing layer to a footplate that is fixed to the concrete wall of the steam generator enclosure. 4 figs.

British Library Electronic Table of Contents (United Kingdom)

The hybrid squeeze-film damper bearing with active control is proposed in this paper and the lubricating with couple stress fluid is also taken into consideration. The pressure distribution and the dynamics of a rigid rotor supported by such bearing are studied. A PD (proportional-plus-derivative) controller is used to stabilize the rotor-bearing system. Numerical results show that, due to the nonlinear factors of oil film force, the trajectory of the rotor demonstrates a complex dynamics with rotational speed ratio s. Poincare maps, bifurcation diagrams, and power spectra are used to analyze the behavior of the rotor trajectory in the horizontal and vertical directions under different operating conditions. The maximum Lyapunov exponent and fractal dimension concepts are used to determine ...

British Library Electronic Table of Contents (United Kingdom)

The ensemble empirical mode decomposition (EEMD) can overcome the mode mixing problem of the empirical mode decomposition (EMD) and therefore provide more precise decomposition results. Wavelet neural network (WNN) possesses the advantages of both wavelet transform and artificial neural networks. This paper combines the merits of EEMD and WNN to propose an automated and effective fault diagnosis method of locomotive roller bearings. First, the vibration signals captured from the locomotive roller bearings are preprocessed by EEMD method and intrinsic mode functions (IMFs) are produced. Second, a kurtosis based method is presented and used to select the sensitive IMF. Third, time- and frequency-domain features are extracted from the sensitive IMF, its frequency spectrum and its envelope spe...

Energy Technology Data Exchange (ETDEWEB)

In this paper, a complete solution of the steady-state Newton-Euler equations describing the motion of the balls in high speed thrust bill bearings is presented. Kinematic equations are derived and used as ancillary equations to obtain the numerical solution of the Newton-Euler equations. This differs from previously reported work where extraneous assumptions (instead of kinematic analysis) are used to allow solutions of these equations. It is shown that the no-slip condition for the ball motion reported in the literature is based on an unnecessary assumption. The correct form of the condition is developed and used in the analysis of the ball motion. The analysis shows the importance of contact angle on both ball motion and contact force. An approximate theory is then developed for determining the optimum contact angle that would result in minimum contact force in high speed ball bearings. The results are compared with experimental data, and ...

Energy Technology Data Exchange (ETDEWEB)

The invention relates to a method for purifying a gas mixture containing at least one undesirable gas compound utilizing certain sulfonamide or sulfamide solvents.

CERN Document Server

View of the CERN / LHC / Alps region from the Jura.

Science.gov (United States)

The patent application describes an anti-friction worm-wheel assembly wherein the anti-friction elements are rollers carried by the worm element. The rollers sequentially move through grooves in the edge surface of the wheel element to transmit drive forc...

Science.gov (United States)

A Pd(0)-catalyzed intramolecular Heck-type reaction of oxime ether has been developed, providing convenient access to heterocyclic oximes. PMID:21964259

UK PubMed Central (United Kingdom)

BackgroundOil palm (Elaeis guineensis Jacq.) is one of the most important oil bearing crops in the world. However, genetic improvement of oil palm through conventional...Full Text Available

UK PubMed Central (United Kingdom)

MicroRNAs (miRNAs) are endogenously encoded small noncoding RNAs, derived by processing of short RNA hairpins, that can inhibit the translation of mRNAs bearing partially complementary target sequences....Full Text Available

UK PubMed Central (United Kingdom)

Synthetic polypeptide antigens of L amino acids, although bearing repeating sequences, are thymus-dependent (L-TD), whereas the same polymers composed of D amino acids are thymus-independent (D-TI),...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundBrevican is a member of the lectican family of aggregating extracellular matrix (ECM) proteoglycans that bear chondroitin sulfate (CS) chains. It is highly expressed in...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The force exerted on the rotor by an active magnetic bearing (AMB) is determined by the current flow in the magnet coils. This force can be controlled very precisely, making magnetic bearings a potential benefit for grinding, where cutting forces act as external disturbances on the shaft, resulting in degraded part finish. It is possible to achieve precise shaft positioning, reduce vibration of the shaft caused by external disturbances, and even damp out resonant modes. Adaptive control is an appealing approach for these systems because the controller can tune itself to account for an unknown periodic disturbance, such as cutting or grinding forces, injected into the system. In this paper the authors show how one adaptive control algorithm can be applied to an AMB system with a periodic disturbance applied to the rotor. An adaptive algorithm was developed and implemented in both simulation and hardware, yielding significant reductions in rotor ...

UK PubMed Central (United Kingdom)

Cortical bone contributes the majority of overall bone mass and bears the bulk of axial loads in the peripheral skeleton. Bone metabolic disorders often are manifested by cortical microstructural changes...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Canada's offshore Atlantic petroleum industry is celebrating its tenth anniversary in 2001. This article chronicles the development of the industry discussing the many challenges and setbacks and the eventual triumphs that accompanied the industry's development over the years. Highlights discussed include shipping first oil from the Cohasset Field in July 1992; the financial crisis caused by the withdrawal of Gulf Oil from the Hibernia consortium in the same year; new funding and the beginning of the gravity-based structure construction at Bulls Arm in 1993; striking oil in the Hibernia Field in 1994; the start of exploration and development of the Terra Nova field by Petro-Canada in the same year, based on the floating production, storage and offloading (FPSO) system, which heralded a new era of offshore development in eastern Canada. Approval by the Nova Scotia government of the third and final phase of the Sable Offshore Energy Project followed in 1996 and the ...

Energy Technology Data Exchange (ETDEWEB)

The Asia-Pacific region will see tremendous growth in demand for electricity in the next few decades and will be an important market for generation equipment and associated services. The Association of Southeast Asian Nations (ASEAN) countries alone anticipate additional power demand of more than 37,000 NM by the year 2000, with an estimated total expenditure of US $85 billion. Trends in recent years show natural gas-fired combined cycle in plants to be fast gaining in popularity over conventional thermal plants. The advantages include increased primary energy conversion efficiency coupled with significant reduction in pollutant emissions, shorter construction times, faster loading rates and reduced staffing requirements. In the computer model used for generation capacity expansion planning in Tenaga Nasional Berhad, clean coal technology models are not used as candidate plants. In the opinion of the authors, this results from a lack of ...

Energy Technology Data Exchange (ETDEWEB)

The core bypass flow in a prismatic very high temperature gas-cooled reactor (VHTR) is one of the important design considerations which impacts considerably on the integrity of reactor core internals including operating fuels. The interstitial gaps are an inherent presence in the reactor core because of tolerances in manufacturing the blocks and the inexact nature of their installation. Furthermore, the geometry of the graphite blocks changes over the lifetime of the reactor because of thermal expansion and irradiation damage. The occurrence of hot spots in the core and lower plenum and hot streaking in the lower plenum (regions of very hot gas flow) will be affected by the bypass flow. In the present study, three-dimensional computational fluid dynamic (CFD) calculations of a typical prismatic VHTR are conducted to understand better the bypass flow phenomenon and establish the evaluation method in the reactor core using ...

International Nuclear Information System (INIS)

The major details of the inspection and replacement of the bearing journals on each of the four heat transport pumps (HTPs) at Wolsung nuclear generating station in Korea are presented in this paper. Investigation following fracture of one of the journals in 1985 revealed that it was excessively hard. The journal material (ASTM A296 CA 40) is considered to be prone to stress corrosion fatigue if the hardness exceeds Rc 40. In 1986 May, during a planned outage, the HTPs were disassembled, the journals were inspected, found to be excessively hard, and all were replaced. At the same time, the pump to motor couplings were all refurbished to ensure proper alignment.

Energy Technology Data Exchange (ETDEWEB)

A manipulator for checking the inside of a vertical, flange-shaped collector of a horizontal steam generator consists of a rotating mast with bearings at the top and bottom ends with a support that can be moved along the length of the mast for the checking system mountings. The support is propelled by a drive spindle placed parallel to the mast with its drive head bearing in the support and locked into a toothed rack attached to the mast. The checking system mountings are fitted in or on the walls of the support and are very close to the box-shaped support. Their retractable arms are hinged.

British Library Electronic Table of Contents (United Kingdom)

Results are presented from an evaluation of the effect of the quality of the iron-ore-bearing raw materials and coke on the performance of blast furnaces at the Novolipetsk Metallurgical Combine. It is shown that the technical-economic indices of the smelting operation are improved by increasing the pellet content of the charge, the basicity of the sinter, and the sinter?s content of the ?5 mm fraction. An analysis of the performance of the blast furnaces on coke with a hot-strength index CSR = 40?60% confirmed the qualitative and quantitative effect of this index on furnace productivity and coke consumption. The analysis also showed that the magnitude of this effect depends on smelting rate and the basicity of the furnace slag.

Energy Technology Data Exchange (ETDEWEB)

The White Rose Oil Project, located in the Jeanne d'Arc Basin 350 km east of St. John's, is reported to continue paying benefits for the oil and gas industry in eastern Canada. The operator, Husky Energy, is said to be on target and expects first oil from the project in late 2005 or early 2006. Peak production for the White Rose Field is projected at 100,000 bbl/d. The project has a total capital cost of $2.35 billion. The first phase of the project, comprised of four wells, including an oil producer, was completed in July. The estimated productive capacity of this well is between 25,000 and 35,000 bbl/d. Other major milestones achieved at the White Rose project include movement of the topside modules onto the Sea Rose floating production, storage and offloading (FPSO) vessel, consisting of 17 lifts during the seven-week program. Individual lifts up to 1,250 tons were carried by the Lampson 2600 Trans-lift crane at the Cow Head Fabrication ...

CERN Document Server

Radiation protection and the management of radioactive waste in the oil and gas industry

Wastenet

condenser, gas refiner, oil (gas) storage tank and dual fuel engine

Energy Technology Data Exchange (ETDEWEB)

Photoelectrochemical oxidation is a potentially interesting method for destroying toxic organic materials. We have studied the photoelectrocatalytic activity of TiO{sub 2} films made by thermal oxidation of titanium, low pressure chemical vapour deposition (LPCVD), and anodisation of titanium. Two model organic compounds have been investigated for photooxidation: methyl phosphonic acid (MPA) which is a nerve gas analogue and 4-chlorophenol (4-CP) which is a chlorinated aromatic compound considered a standard for the evaluation of the TiO{sub 2} / UV processes. In addition to photoelectrochemical characterisation the films have been characterised by profilometry, XRD, AFM, photocurrent spectroscopy and Raman microscopy. Correlations have been made between the physical properties of the thin films and their catalytic activities. The most catalytic sample of thermally oxidised titanium was prepared at 400 deg C, and the presence of anatase was shown by XRD, MPA ...

Energy Technology Data Exchange (ETDEWEB)

A publication on Norwegian gas and gas export. The content is wide spread from use of gas in daily life via sub sea pipeline repair systems to an overview over tomorrows gas fields. (AG)

Energy Technology Data Exchange (ETDEWEB)

Currently there are four different concept studies trying to optimise the detector for the requirements at the ILC. In three of these detector concepts a time projection chamber (TPC) is foreseen as the main tracking device. To achieve the intended spatial resolution of 100 {mu}m, micro pattern gas detectors (MPGD) are considered for gas amplification. The two different MPGDs discussed for the ILC TPC are Micro-Mesh Gaseous Detectors (Micromegas) and Gas Electron Multiplier foils (GEMs). The current thesis shows resolution studies with a TPC prototype equipped with a triple GEM readout structure. A hodoscope made up of silicon strip sensors gives a precision reference track, allowing an unbiased measurement of the spatial resolution. High statistics measurements have been conducted at the DESY test beam facility, which provides positrons with a tunable energy between 1 GeV and 6 GeV. Using the independent measurement of the ...

International Nuclear Information System (INIS)

The effect of electron beam welding parameters on fusion zone (FZ) microstructure and porosity in a Ti-6.8 Al-3.42 Mo-1.9 Zr-0.21 Si alloy (Russian designation VT 9) has been investigated. It has been observed that the FZ grain width increased continuously with increase in heat input when the base metal was in the #beta# heat-treated condition, while in the #alpha# + #beta# heat-treated base metal welds, the FZ grain width increased only after a threshold energy input. The difference is attributed to both the weld thermal cycle and the pinning effect of equiaxed primary alpha on grain growth in the heat-affected zone (HAZ) of #alpha# + #beta# heat-treated base metal. Postweld heat treatment (PWHT) in the subtransus and supertransus regions did not alter the columnar grain morphology in the FZ, possibly due to the lack of enough driving force for the formation of new grains by the breaking up of the columnar grains and grain boundary movement for grain growth. The ...

Science.gov (United States)

... The CENTCOM AOR encompasses the world's most energy-rich region, with the Arabian Gulf region and Central Asia together ...

Science.gov (United States)

... Uninterrupted access to and use of critical infrastructure in the Arabian Gulf region are key to the successful prosecution of the Global War on Terror ...

Energy Technology Data Exchange (ETDEWEB)

In the past, Condition Monitoring Systems (CMS) still showed weaknesses during the employment in the damage diagnosis and/or early failure detection of damages of roller bearings in transmissions of wind power plants. This is not only due to the insufficient consideration of the variable frequency of the wind power plants during the internal processing. The presently used methods of analysis result from the communication technology and are used successfully for years at frequency solid systems. Usually, only too few information are at the disposal to the supplier of CMS in order to parametrize their systems on the respective application particularly. An exact knowledge of the internal structure of the object to be diagnosed is compellingly necessary for a successful diagnosis so that a loadable statement based on the acquired measuring data base becomes possible. Furthermore, one must clarify the borders of the presently used systems. The theory of these systems is ...

Energy Technology Data Exchange (ETDEWEB)

This study focuses the granitoids of center-southern portion of Guyana Shield, southeastern Roraima, Brazil. The region is characterized by two tectonic-stratigraphic domains, named as Central Guyana (GCD) and Uatuma-Anaua (UAD) and located probably in the limits of geochronological provinces (e.g. Ventuari-Tapajos or Tapajos-Parima, Central Amazonian and Maroni-Itacaiunas or Transamazon). The aim this doctoral thesis is to provide new petrological and lithostratigraphic constraints on the granitoid rocks and contribute to a better understanding of the origin and geo dynamic evolution of Guyana Shield. The GCD is only locally studied near to the UAD boundary, and new geological data and two single zircon Pb-evaporation ages in mylonitic biotite granodiorite (1.89 Ga) and foliated hastingsite-biotite granite (1.72 Ga) are presented. These ages of the protholiths contrast with the lithostratigraphic picture in the other areas of Cd (1.96-1.93 Ga). ...

International Nuclear Information System (INIS)

An overview is given the expected amount of natural gas that can be produced from small gas fields in the Netherlands in the next 20 years.

Energy Technology Data Exchange (ETDEWEB)

The origin of natural gas in the Japanese oil and gas fields are geochemically studied. Samples are taken from structural natural gas, surface gas seepage, water-dissolved natural gas and coal-field gas of the Japan Sea coast area. The origins of primary hydrocarbons are classified into bacteria gas and thermogenic gas, the latter being subclassified into gas in oil production zone with the per million deviation of the carbon isotope (/sup 13/C/sup 1/) of methane less than -35 and those gases with maturity higher than this. Surface gas seepage is subjected to migration and bacterial oxidation. Coal gas is similar to oil gas. The CO/sub 2/ concentration is 0 - 2% and /sup 13/CO/sub 2/ deviations from -30 - +30. The origin can be barely ...

International Nuclear Information System (INIS)

Beta-21S is a new, metastable-beta titanium alloy which exhibits excellent oxidation resistance and mechanical properties at elevated temperatures. From a weld solidification standpoint, this alloy chemistry is of particular interest because its major beta-stabilizing elements (Mo and Nb) both exhibit equilibrium partitioning ratios (k_o) greater than unity, indicating their simultaneous partitioning during weld solidification to the initial solid to form (i.e., dendrite cores), and correspondingly their depletion in the final regions of solidification (i.e., dendrite interstices). Such elemental partitioning, if retained down to room temperature, may be expected to promote local variations in the postweld aging response. The objectives of the present investigation were to characterize Gas Tungsten-Arc weld solidification and HAZ liquation phenomena in Beta-21S and to examine the influence of residual microsegregation in the weld zone on alpha ...

International Nuclear Information System (INIS)

The present guidelines supplement the 'VGB guidelines for the reduction of noise in thermal power plants' with indications for the ordering and quality assurance of the individual noise-producing machines and equipment of power plant operation. These guides are to simplify the commissioning and delivering for the orderer and deliverer. In addition, these guidelines are to lead to a successful cooperation of all parties in the reduction of the sound radiation. A precondition for this is an explanation of the sound technical demands which must be made on the single machines or mechanical equipment in power plant systems. A protection of the neighbourhood as well as operational personnel against noise according to the state of technology is to be achieved by a clear form of ordering and quality assurance. The ordering and assurance procedure for all aggregates in the region of the grounds of a power plant up to the high-voltage side of the machine transformers is ...