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1

Coso Hot Springs: A Condensate Fed Geothermal Feature  

Microsoft Academic Search

The Coso Hot Springs are located almost two miles from the Coso geothermal field within the China Lake Naval Air Weapons Station, China Lake, California. The hot springs are about 16 m above the adjacent valley floor and because of their position are not believed to be in good hydrologic connection with the regional groundwater water table. Shortly after the

M. A. Person; D. Cohen; A. Sabin; J. Unruh; C. Gable; G. Zyvoloski; D. Meade; S. Bjornstad; F. Monastero

2007-01-01

2

Long-Term Testing of Geothermal Wells in the Coso Hot Springs KGRA  

Microsoft Academic Search

Three wells have been drilled by the Los Angeles Department of Water and Power at the Coso Hot Springs KGRA. A long-term flow test was conducted involving one producing well (well 43-7), one injector (well 88-1), and two observation wells (well 66-6 and California Energy Coâs well 71A-7). ;\\u000aThis paper presents the equipment and techniques involved and the results

S. Sanyal; A. Menzies; E. Granados; S. Sugine; R. Gentner

1987-01-01

3

Long-Term Testing of Geothermal Wells in the Coso Hot Springs KGRA  

SciTech Connect

Three wells have been drilled by the Los Angeles Department of Water and Power at the Coso Hot Springs KGRA. A long-term flow test was conducted involving one producing well (well 43-7), one injector (well 88-1), and two observation wells (well 66-6 and California Energy Co’s well 71A-7). This paper presents the equipment and techniques involved and the results from the long-term test conducted between December 1985 and February 1986. 1 tab., 9 figs.

Sanyal, S.; Menzies, A.; Granados, E.; Sugine, S.; Gentner, R.

1987-01-20

4

Correlation of hydrothermal sericite composition with permeability and temperature, Coso Hot Springs geothermal field, Inyo County, California  

SciTech Connect

Petrographic and geochemical analyses of cuttings from six wells in the Coso Hot Springs geothermal field show a systematic variation in the occurrence, texture, and composition of sericite that can be correlated with high permeability production zones and temperature. The wells studied intersect rhyolitic dikes and sills in the fractured granitic and dioritic basement rocks which serve as the reservoir for the geothermal system. Low-permeability non-productive zones in the wells contain coarse-grained compositionally homogeneous primary muscovite. High-permeability production zones are characterized by abundant fine-grained hydrothermal sericite that exhibits a systematic increase in K and Al and decrease in Si with increasing temperature. Calculated activities of the muscovite and pyrophyllite components for the hydrothermal sericites increase and decrease, respectively, with increasing temperature. This trend is similar to that reported for geothermal systems at Roosevelt Hot Springs and the Salton Sea, although sericites from these systems are compositionally distinct from those at Coso. Computed distribution of aqueous species in the geothermal fluids were combined with activity phase diagrams accounting for hydrothermal sericite compositions to determine a pH of 6.1 for the geothermal fluids. These calculations suggest that hydrothermal sericites are in local equilibrium with the geothermal fluid, but primary muscovites in low permeability zones are metastable. Compositional data on hydrothermal sericite from active geothermal systems at Coso Hot Springs, Roosevelt Hot Springs, and the Salton Sea show that the mineral is sensitive to temperature and water/rock ratios and may be a useful indicator of high permeability zones within a geothermal field.

Bishop, B.P.; Bird, D.K.

1985-01-01

5

Regulatory, Land Ownership, and Water Availability Factors for a Magma Well: Long Valley Caldera and Coso Hot Springs, California  

SciTech Connect

The U.S. Department of Energy is currently engaged in a program to demonstrate the engineering feasibility of extracting thermal energy from high-level molten magma bodies. The program is being carried out under the direction of Sandia National Laboratories where a number of individual projects support the overall program. The existing program elements include (1) high-temperature materials compatibility testing; (2) studies of properties of melts of various compositions; and (3) the investigation of the economics of a magma energy extraction system. Another element of the program is being conducted with the cooperation of the U.S. Geological Survey, and involves locating and outlining magma bodies at selected sites using various geophysical techniques. The ultimate goal here will be to define the limits of a magma body as a drilling target. During an earlier phase of the program, more than twenty candidate study sites considered were evaluated based upon: (1) the likelihood of the presence of a shallow magma chamber, (2) the accessibility of the site, and (3) physical and institutional constraints associated with each site with respect to performing long-term experiments. From these early phase activities, the number of candidate sites were eventually narrowed to just 2. The sites currently under consideration are Coso Hot Springs and the Long Valley caldera (Figure 1). This report describes certain attributes of these sites in order to help identify potential problems related to: (1) state and federal regulations pertaining to geothermal development; (2) land ownership; and (3) water resource availability. The information sources used in this study were mainly maps, publications, and informative documents gathered from the California Division of Oil and Gas and the U.S. Department of the Interior. Environmental studies completed for the entire Long Valley caldera study area, and for portions of the Coso Hot Springs study area were also used for reference.

Blackett, Robert

1985-09-01

6

Coso Monitoring Program, October 1992 through September 1993  

SciTech Connect

The Coso Monitoring Program is a continuing effort in support of the Navy's geothermal resources within the Known Geothermal Resource Area (KGRA). Data are presented on the monitoring of steam flow rates and temperatures, water levels in ponds and wells, water chemistry, and rainfall in the Coso Hot Springs Resort Area. A monthly photographic essay of the mudfields and pools shows the variation of the surface water levels throughout the year. Coso monitor program, Steam Flow, Coso hot springs, Barometric pressure, Environmental monitoring, Water analysis, Ambient temperature, Geothermal development, Water level, Relative humidity.

Bjornstad, S.C.; Monahan, J.H.; Sprouse, J.K.

1994-01-01

7

Coso Monitoring Program, January 1981 through December 1983  

NASA Astrophysics Data System (ADS)

The Coso monitoring program is a continuing effort in support of the development of the Navy's geothermal resources within the Coso Known Geothermal Resource Area (KGRA). Data are presented on the monitoring of steam flow rates and temperatures, water levels in ponds and wells, water chemistry, temperature logs of shallow wells, and rainfall in the Coso Hot Springs Resort area. A weekly photographic essay of the mud pots and pools shows the variation of surface water levels thoughout the year.

Bjornstad, S. C.; Rodgers, C. R.

1984-09-01

8

Coso monitoring program, October 1993 through September 1994. Report for 1 October 1993-30 September 1994  

SciTech Connect

The Coso Monitoring Program is a continuing effort in support of the Navy`s geothermal resources within the Known Geothermal Resource Area (KGRA). Data are presented on the monitoring of steam flow rates and temperatures, water levels in ponds and wells, water chemistry, and rainfall in the Coso Hot Springs Resort Area. A monthly photographic essay of the mudfields and pools shows the variation of the surface water levels throughout the year.

Bjornstad, S.C.; Monahan, J.H.; Sprouse, J.K.

1995-01-01

9

Time-Dependent Tomography and Microearthquake Moment Tensors in the Coso Geothermal Area  

Microsoft Academic Search

The Coso geothermal area, California, has produced hot water and steam for electricity generation for more than a decade. During this time, a permanent network of three-component digital borehole seismometers operated by the U.S. Navy has monitored the abundant microearthquake activity in the producing region. A 14-station portable array of three-component digital instruments has supplemented the Navy network since about

B. R. Julian; G. R. Foulger; K. Richards-Dinger; F. Monastero

2005-01-01

10

Geologic Study of the Coso Formation  

SciTech Connect

There have been great advances in the last 20 years in understanding the volcanic, structural, geophysical, and petrologic development of the Coso Range and Coso geothermal field. These studies have provided a wealth of knowledge concerning the geology of the area, including general structural characteristics and kinematic history. One element missing from this dataset was an understanding of the sedimentology and stratigraphy of well-exposed Cenozoic sedimentary strata - the Coso Formation. A detailed sedimentation and tectonics study of the Coso Formation was undertaken to provide a more complete picture of the development of the Basin and Range province in this area. Detailed mapping and depositional analysis distinguishes separate northern and southern depocenters, each with its own accommodation and depositional history. While strata in both depocenters is disrupted by faults, these faults show modest displacement, and the intensity and magnitude of faulting does no t record significant extension. For this reason, the extension between the Sierran and Coso blocks is interpreted as minor in comparison to range bounding faults in adjacent areas of the Basin and Range.

D. L. Kamola; J. D. Walker

1999-12-01

11

Microearthquake moment tensors from the Coso Geothermal area  

SciTech Connect

The Coso geothermal area, California, has produced hot water and steam for electricity generation for more than 20 years, during which time there has been a substantial amount of microearthquake activity in the area. Seismicity is monitored by a high-quality permanent network of 16 three-component digital borehole seismometers operated by the US Navy and supplemented by a ~ 14-station portable array of surface three-component digital instruments. The portable stations improve focal sphere coverage, providing seismic-wave polarity and amplitude data sets sufficient for determining full moment-tensor microearthquake mechanisms by the linearprogramming inversion method. We have developed a GUI-based interface to this inversion software that greatly increases its ease of use and makes feasible analyzing larger numbers of earthquakes than previously was practical. We show examples from an injection experiment conducted in well 34-9RD2, on the East Flank of the Coso geothermal area. This tight well was re-drilled February – March 2005 with the intention of hydrofracturing it, but instead, pervasive porosity and fractures were encountered at about 2660 m depth. Total drilling mud losses occurred, obviating the need to stimulate the well. These mud losses induced a 50-minute swarm of 44 microearthquakes, with magnitudes in the range -0.3 to 2.6. Most of the largest microearthquakes occurred in the first 2 minutes. Accurate relative relocations and moment tensors for the best-recorded subset reveal fine details of the fracture that was stimulated. This comprised a fault striking at N 20° E and dipping at 75° to the WNW, which propagated to the NNE and upward. Co-injection focal mechanisms reveal combined crack-opening and shear motion. Stress release and mode of failure differed between the pre-, co- and post-swarm periods. Some post-swarm events involved cavity collapse, suggesting that some of the cavity opening caused by the fluid injection was quickly reversed. Stress & mode of failure had not returned to pre-swarm conditions within 1 month following the injection, posing the question of how long stress perturbations persist following a stimulation experiment. This question may be answered by processing data spanning a longer postinjection period, work that is currently underway and will be reported in this presentation.

Julian, B.R.; G.R. Foulger; F. Monastero

2007-04-01

12

Clinopyroxene thermobarometry of basalts from the Coso and Big Pine volcanic fields, California  

Microsoft Academic Search

The Coso and Big Pine volcanic fields of eastern California exhibit different magmatic histories. The Big Pine field erupted only basalt lavas, some of which bear mantle xenoliths, whereas the Coso field erupted both basalt and rhyolite and is a major geothermal resource. These different magmatic products could be explained if Coso basalts stalled in the crust before erupting, providing

B. E. Mordick; A. F. Glazner

2006-01-01

13

Coso geothermal environmental overview study ecosystem quality  

SciTech Connect

The Coso Known Geothermal Resource Area is located just east of the Sierra Nevada, in the broad transition zone between the Mohave and Great Basin desert ecosystems. The prospect of large-scale geothermal energy development here in the near future has led to concern for the protection of biological resources. Objectives here are the identification of ecosystem issues, evaluation of the existing data base, and recommendation of additional studies needed to resolve key issues. High-priority issues include the need for (1) site-specific data on the occurrence of plant and animal species of special concern, (2) accurate and detailed information on the nature and extent of the geothermal resource, and (3) implementation of a comprehensive plan for ecosystem protection.

Leitner, P.

1981-09-01

14

3D Magnetotelluric characterization of the COSO GeothermalField  

SciTech Connect

Knowledge of the subsurface electrical resistivity/conductivity can contribute to a better understanding of complex hydrothermal systems, typified by Coso geothermal field, through mapping the geometry (bounds and controlling structures) over existing production. Three-dimensional magnetotelluric (MT) inversion is now an emerging technology for characterizing the resistivity structures of complex geothermal systems. The method appears to hold great promise, but histories exploiting truly 3D inversion that demonstrate the advantages that can be gained by acquiring and analyzing MT data in three dimensions are still few in number. This project will address said issue, by applying 3D MT forward modeling and inversion to a MT data set acquired over the Coso geothermal field. The goal of the project is to provide the capability to image large geothermal reservoirs in a single self-consistent model. Initial analysis of the Coso MT data has been carried out using 2D MT imaging technology to construct an initial 3D resistivity model from a series of 2D resistivity images obtained using the inline electric field measurements (Zxy impedance elements) along different measurement transects. This model will be subsequently refined through a 3D inversion process. The initial 3D resistivity model clearly shows the controlling geological structures possibly influencing well production at Coso. The field data however, also show clear three dimensionality below 1 Hz, demonstrating the limitations of 2D resistivity imaging. The 3D MT predicted data arising from this starting model show good correspondence in dominant components of the impedance tensor (Zxy and Zyx) above 1Hz. Below 1 Hz there is significant differences between the field data and the 2D model data.

Newman, Gregory A.; Hoversten, Michael; Gasperikova, Erika; Wannamaker, Philip E.

2005-01-01

15

STRESS AND FAULTING IN THE COSO GEOTHERMAL FIELD: UPDATE AND RECENT RESULTS FROM THE EAST FLANK AND COSO WASH  

Microsoft Academic Search

We integrate new geologic mapping and measurements of stress orientations and magnitudes from wells 34-9RD2 and 58A-10 with existing data sets to refine a geomechanical model for the Coso geothermal field. Vertically averaged stress orientations across the field are fairly uniform and are consistent with focal mechanism inversions of earthquake clusters for stress and incremental strain. Active faults trending NNW-SSE

Nicholas C. Davatzes; Stephen H. Hickman

2006-01-01

16

Microearthquake characterisation of an artificially stimulated hydraulic fracture at the Coso geothermal area, California  

NASA Astrophysics Data System (ADS)

The Coso geothermal area, California, has produced hot water and steam for electricity generation for more than 20 years, during which time intense microearthquake activity has occurred in the area, much of it induced by geothermal production. The seismicity is monitored by a high-quality permanent network of three- component digital borehole seismometers operated by the US Navy and supplemented by a ~ 14-station portable array of surface three-component digital instruments. The purpose of the portable stations is to improve seismic monitoring around wells in which fluid injection/hydrofracturing experiments are conducted. The first injection experiment was conducted in well 34-9RD2, on the East Flank of the Coso geothermal area. This well was re-drilled February - March 2005 with the intention of hydrofracturing it by injecting fluids under pressure. Instead, natural fractures were encountered at about 2,660 m depth. Drilling muds entered the fractures, obviating the need to stimulate the well. These mud losses induced a 50-minute swarm of 44 microearthquakes, with magnitudes in the range -0.3 to 2.6. Most of the largest microearthquakes occurred in the first 2 minutes. Accurate relative relocations and moment tensors for the best-recorded subset reveal fine details of the fracture stimulated. This comprised a fault striking at N 20 deg E and dipping at 75 deg to the WNW, which propagated to the NNE and upward. Co-injection focal mechanisms reveal combined crack- opening and shear motion. Stress release and mode of failure differed between the pre-, co- and post-swarm periods. Some post-swarm events involved cavity collapse, suggesting that some of the cavities opened by the fluid injection closed quickly. Stress and mode of failure had not returned to pre-swarm conditions within 1 month following the injection, posing the question of how long stress perturbations persist following a stimulation experiment. This question may be answered by processing data spanning a longer post-injection period, work that is currently in hand and will be reported in this presentation. We will also report on progress in developing a Graphical User Interface to facilitate deriving moment tensors from microearthquakes using amplitude ratios.

Foulger, G. R.; Julian, B. R.; Monastero, F. C.

2006-12-01

17

Structural investigations at the Coso geothermal area using remote sensing information, Inyo County, California  

SciTech Connect

Remote sensing studies have been made in and adjacent to the Coso geothermal field using TM FCC satellite imagery, 1:100,000 scale, US Geological Survey orthophotos, 1:24,OOO scale, and proprietary black-and-white photography by California Energy Company, Inc., at various scales including black-and-white positive film transparencies at a scale of 1:6,000. These studies have been made in an attempt to understand the complex geology seen on the surface and to try to improve the method of locating geothermal wells. The tectonic history indicated by remote sensing, gravity, magnetic, refraction and reflection seismic studies indicates structure caused by a period of thrusting and folding followed by local and regional slumping and collapse, which is continuing today. During Sevier/Laramide orogeny, the Sierra Nevada Mountains were thrust eastward over Rose Valley/lndian Wells Valley. Relatively thin granitic/metamorphic plates were folded to form the Coso Range and thrust eastward over Coso Wash. In turn, the Argus Range to the east was thrust eastward over Panamint Valley. As soon as topographic relief, developed by the thrusting, was high enough, the entire area started to collapse, in some cases using the original thrust planes for slumping. The granitic/metamorphic rocks forming the surface of the Coso Range anticline slumped eastward into Coso Wash and westward toward Rose Valley. The Sierra front slumped eastward into Rose Valley/Indian Wells Valley, and the entire range may have had westward on the original thrust faults. The thin basalts on the east side of Coso Wash slumped westward into Coso Wash. Several basaltic eruptions of 3-4 million years ago used the zone between slump blocks as eruption sites. Regional slumping for the entire area toward the southeast is indicated on satellite imagery.

Austin, W.H. (Austin Enterprises, Santa Rose, CA (USA))

1990-05-01

18

Crustal structure determined from ambient noise tomography near the magmatic centers of the Coso region, southeastern California  

Microsoft Academic Search

We apply seismic ambient noise tomography to image and investigate the shallow shear velocity structure beneath the Coso geothermal field and surrounding areas. Data from a PASSCAL experiment operated within the Coso geothermal field between 1998 and 2000 and surrounding broadband stations from the Southern California Seismic Network are acquired and processed. Daily cross correlations of ambient noise between all

Yingjie Yang; Michael H. Ritzwoller; Craig H. Jones

2011-01-01

19

Magmatic Evolution of the Coso Geothermal Area, California  

NASA Astrophysics Data System (ADS)

Geothermal energy in the Coso field owes its origin to basaltic magmatism. Volcanism commenced ~3.5 Ma ago, coincident with a widespread Pliocene outburst in eastern California. Although most basalts associated with this event are highly potassic, those at Coso are not. Pliocene volcanic rocks at Coso (erupted between 3.5-2 Ma) range from basalt to rhyodacite, show abundant petrographic evidence for open-system behavior (e.g., quartz xenocrysts in basalts), and have compositions consistent with mixing. In contrast, Pleistocene rocks, erupted <1 Ma ago, comprise a strongly bimodal suite of mildly alkalic basalt and high-silica rhyolite. Pleistocene basalts differ from their Pliocene counterparts in generally having more depleted 87Sr/86Sr and ?Nd values (0.703, +7 vs. 0.704, +4); higher TiO2 and Nb; lower MgO; greater stalling depths in the crust. Pliocene rocks are distinctly arc-like even though they were erupted ~10 Ma after subduction ceased. In contrast, Pleistocene basalts have a distinctly OIB-like geochemical signature, with undepleted high field strength elements and plume-like radiogenic isotope ratios; these characteristics are shared with late Cenozoic basalts across the western U.S. Rare Pleistocene basalts that were erupted from within the footprint of the rhyolite field have notably high TiO2 contents (>3 wt%), similar to basalts from the Columbia River and Snake River Plain fields. Unlike Pliocene rocks, which scatter toward isotopic values of local basement with increasing SiO2, Pleistocene rhyolites generally have high and consistent ?Nd (+1 - +2.5). Producing this signature by AFC processes involving basalt and basement rocks requires remarkably consistent mixing and fractionation at small-volume volcanic centers separated by several km. Alternatively, high ?Nd values in the rhyolites could have been produced by partial melting of Pliocene basalts and andesites, which have very similar Nd isotopic compositions. Increasing ?Nd in silicic rocks as the geothermal production area is approached suggests that the magmatic flux is highest there even though erupted volumes are significantly larger outside the geothermal area. One scenario consistent with the above data is as follows. Post-subduction tectonic events triggered magmatism at 3.5 Ma, tapping fertile, subduction-metasomatized lithospheric mantle. Basalts stalled in and partially melted the mid-crust, generating a mixed-magma series and copious volcanism. Depletion of the mantle source by 2 Ma led to a hiatus in magmatism. A change in basalt chemistry to OIB- affinity in the last 1 Ma suggests a profound change in magma source - likely involving decompression melting of ascending asthenospheric mantle, perhaps related to lithosphere delamination. Injection of such magmas into the lower crust, would have generated rhyolites by remelting of earlier emplaced mafic bodies - imparting a juvenile isotopic signature in the late rhyolites. Precursory Pliocene magmatism is a common feature of other western U.S. geothermal areas, including Twin Peaks, The Geysers, and Long Valley.

Glazner, A. F.; Miller, J. S.; Leeman, W. P.; Johnson, B. R.; Monastero, F. C.

2007-12-01

20

Hot Sauce Hot Spots  

NSDL National Science Digital Library

In this activity, learners model hot spot island formation, orientation and progression with condiments. Learners squirt a thick condiment sauce on a coarsely woven fabric to model how volcanic island hot spots form.

Muller, Eric

2007-01-01

21

COMPARISON OF ACOUSTIC AND ELECTRICAL IMAGE LOGS FROM THE COSO GEOTHERMAL FIELD, CA  

Microsoft Academic Search

Electrical and acoustic image logs collected from well 58A-10 in crystalline rock on the eastern margin of the Coso Geothermal Field, CA, reveal different populations of planar structures intersecting the borehole. Electrical image logs appear to be sensitive to variations in mineralogy, porosity, and fluid content that highlight both natural fractures and rock fabrics. These fabric elements account for about

NICHOLAS C. DAVATZES; STEVE HICKMAN

22

Variations in dissolved gas compositions of reservoir fluids from the Coso geothermal field  

SciTech Connect

Gas concentrations and ratios in 110 analyses of geothermal fluids from 47 wells in the Coso geothermal system illustrate the complexity of this two-phase reservoir in its natural state. Two geographically distinct regions of single-phase (liquid) reservoir are present and possess distinctive gas and liquid compositions. Relationships in soluble and insoluble gases preclude derivation of these waters from a common parent by boiling or condensation alone. These two regions may represent two limbs of fluid migration away from an area of two-phase upwelling. During migration, the upwelling fluids mix with chemically evolved waters of moderately dissimilar composition. CO{sub 2} rich fluids found in the limb in the southeastern portion of the Coso field are chemically distinct from liquids in the northern limb of the field. Steam-rich portions of the reservoir also indicate distinctive gas compositions. Steam sampled from wells in the central and southwestern Coso reservoir is unusually enriched in both H{sub 2}S and H{sub 2}. Such a large enrichment in both a soluble and insoluble gas cannot be produced by boiling of any liquid yet observed in single-phase portions of the field. In accord with an upflow-lateral mixing model for the Coso field, at least three end-member thermal fluids having distinct gas and liquid compositions appear to have interacted (through mixing, boiling and steam migration) to produce the observed natural state of the reservoir.

Williams, Alan E.; Copp, John F.

1991-01-01

23

Crustal stress heterogeneity in the vicinity of a geothermal field: Coso Geothermal Field, CA  

NASA Astrophysics Data System (ADS)

Borehole induced structures seen in image logs from the Coso Geothermal Field, CA record variation in the azimuth of principal stress. Image logs of these structures from five boreholes were analyzed to quantify the stress heterogeneity for three geologically distinct locations: two boreholes within the Coso Geothermal Field (one in an actively produced volume), two on the margin of the Coso Geothermal Field and outside the production area, and a control borehole several tens of kilometers south of the Coso Geothermal Field. Average directions of Shmin and its standard deviation are similar along the eastern portion of the geothermal field at ˜107 +/- 28°; this is distinct from the western portion which has an azimuth of 081 +/- 18° and also distinct from outside the geothermal field where the average azimuth is 092 +/- 47°. These relationships suggest a correlation of stress orientation and heterogeneity with slip on the Coso Wash fault, suggesting that ˜20 years of production has not affected the Shmin.orientation. The slope of power spectrum quantifies the length-scale dependence of stress rotations for the volume of the brittle crust penetrated by each borehole. Spectral analysis was applied to the depth variation of stress direction and it demonstrates that: (1) the data set contains distinct wavelengths of stress rotation, (2) that the relative power of these wavelengths in the total scaling of stress directions demonstrates a fractal distribution and (3) in a manner consistent with earthquakes causing the stress rotations. While the vertically averaged Shmin orientation for the three eastern boreholes varied by as little as 1°, the spectral slopes varied by 0.4 log (deg2 *m)(m) from the inside to the margin unproduced areas of the Coso Geothermal Field. The two boreholes inside the field had spectral slopes within one standard deviation, even though Shmin orientations were not parallel. These results suggest that at the kilometer length scale, the source of stress heterogeneity is dominated by proximity to recent fault slip, whereas the centimeter to meter stress heterogeneity is dominated by earthquake activity.

Blake, Kelly

24

Rock Magnetic and Paleointensity Study of Eastern California's ~83 Ma Golden Bear and Coso Dikes  

NASA Astrophysics Data System (ADS)

Extraordinary intermediate-composition (Kspar +/- quartz andesite porphyry) dikes are coincident with the end of Sierra Nevada magmatism and crop out on both the east and the west sides of Owens Valley, but offset dextrally by >60 km. If this offset represents ancient (possibly Cretaceous) strike-slip partitioning of Pacific-North America plate boundary strain, then at least one of the south- and east-sited Coso dikes might be expected to be paleomagnetically "identical" to its presumed paleo-contiguous, north- and west-sited Golden Bear partner. Accompanying a directional study by Pluhar and colleagues at CSU-Fresno, we are characterizing magnetic mineralogy, fabric, and thermal lability of Coso dikes and the Golden Bear dike. We are also applying the pTRM difference multi-specimen paleointensity technique to these samples, testing for across-Owens Valley correlation.

Feldman, M.; Raub, T. D.

2009-12-01

25

The Coso Geothermal Area: A Laboratory for Advanced MEQ Studies for Geothermal Monitoring  

Microsoft Academic Search

The permanent 16-station network of three-component digital seismometers at the Coso geothermal area, California, supplemented by 14 temporary instruments deployed in connection with the DOE Enhanced Geothermal Systems (EGS) Project, provides high-quality microearthquake (MEQ) recordings that are well suited to monitoring a producing geothermal area. We are currently using these data to investigate structure and active processes within the geothermal

Bruce R. Julian; Gillian R. Foulger; Keith Richards-Dinger

26

GEOLOGIC FRAMEWORK OF THE EAST FLANK, COSO GEOTHERMAL FIELD: IMPLICATIONS FOR EGS DEVELOPMENT  

Microsoft Academic Search

The Coso Geothermal Field is a large, high temperature system located in eastern California on the western edge of the Basin and Range province. The East Flank of this field is currently under study as a DOE-funded Enhanced Geothermal Systems (EGS) project. This paper summarizes petrologic and geologic investigations on two East Flank wells, 34A-9 and 34-9RD2 conducted as part

K. M. Kovac; J. N. Moore; S. J. Lutz

27

36Cl/Cl ratios in geothermal systems: preliminary measurements from the Coso Field  

SciTech Connect

The {sub 36}Cl/Cl isotopic composition of chlorine in geothermal systems can be a useful diagnostic tool in characterizing hydrologic structure, in determining the origins and age of waters within the systems, and in differentiating the sources of chlorine (and other solutes) in the thermal waters. The {sub 36}Cl/Cl values for several geothermal water samples and reservoir host rock samples from the Coso, California geothermal field have been measured for these purposes. The results indicate that most of the chlorine is not derived from the dominant granitoid that host the geothermal system. If the chlorine was originally input into the Coso subsurface through meteoric recharge, that input occurred at least 1-1.25 million years ago. The results suggest that the thermal waters could be connate waters derived from sedimentary formations, presumably underlying and adjacent top the granitic rocks, which have recently migrated into the host rocks. Alternatively, most of the chlorine but not the water, may have recently input into the system from magmatic sources. In either case, the results indicate that most of the chlorine in the thermal waters has existed within the granitoid host rocks for no more than about 100,00-200,00 years. this residence time for the chlorine is similar to residence times suggested by other researchers for chlorine in deep groundwaters of the Mono Basin north of the Coso field.

Nimz, G.J.; Moore, J.N.; Kasameyer, P.W.

1997-07-01

28

Anomalous shear wave attenuation in the shallow crust beneath the Coso volcanic regionn, California ( USA).  

USGS Publications Warehouse

We use seismograms of local earthquakes to image relative shear wave attenuation structure in the shallow crust beneath the region containing the Coso volcanic-geothermal area of E California. Seismograms of 16 small earthquakes show SV amplitudes which are greatly diminished at some azimuths and takeoff angles, indicating strong lateral variations in S wave attenuation in the area. 3-D images of the relative S wave attenuation structure are obtained from forward modeling and a back projection inversion of the amplitude data. The results indicate regions within a 20 by 30 by 10 km volume of the shallow crust (one shallower than 5 km) that severely attenuate SV waves passing through them. These anomalies lie beneath the Indian Wells Valley, 30 km S of the Coso volcanic field, and are coincident with the epicentral locations of recent earthquake swarms. No anomalous attenuation is seen beneath the Coso volcanic field above about 5 km depth. Geologic relations and the coincidence of anomalously slow P wave velocities suggest that the attenuation anomalies may be related to magmatism along the E Sierra front.-from Authors

Sanders, C.; Ho-Liu, P.; Rinn, D.; Hiroo, Kanamori

1988-01-01

29

Hot Science: Hot rocks  

NSDL National Science Digital Library

This site explores two kinds of igneous rock, pumice and granite. Pumice is an example of extrusive igneous rock, while granite is an example of intrusive igneous rock. Intrusive indicates that the magma was forced close to the surface, but then cooled more slowly underneath the surface. The question, "How hot is Lava?" is linked to an explanation of the heat of lava, why it must be sampled when it is very hot, and how the samples are taken.

30

Pleistocene high-silica rhyolites of the Coso volcanic field, Inyo County, California.  

USGS Publications Warehouse

The high-silica rhyolite domes and lava flows of the bimodal Pleistocene part of the Coso volcanic field provide an example of the early stages of evolution of a silicic magmatic system of substantial size and longevity. Major and trace element compositions are consistent with derivation from somewhat less silicic parental material by liquid state differentiation processes in compositionally and thermally zoned magmatic systems. Seven chemically homogeneous eruptive groups can be distinguished on the basis of trace element and K/Ar data. The oldest two groups are volumetrically minor and geochemically distinct from the younger groups, all five of which appear to have evolved from the same magmatic system. Erupted volume-time relations suggest that small amounts of magma were bled from the top of a silicic reservoir at a nearly constant long-term rate over the last 0.24Ma. The interval of repose between eruptions appears to be proportional to the volume of the preceding eruptive group. This relationship suggests that eruptions take place when some parameter which increases at a constant rate reaches a critical value; this parameter may be extensional strain accumulated in roof rocks. Extension of the lithosphere favors intrusion of basalt into the crust, attendant partial melting, and maintenance of a long-lived silicic magmatic system. The Coso silicic system may contain a few hundred cubic kilometers of magma. The Coso magmatic system may eventually have the potential for producing voluminous pyroclastic eruptions if the safety valve provided by rapid crustal extension becomes inadequate to 1) defuse the system through episodic removal of volatile-rich magma from its top and 2) prohibit migration of the reservoir to a shallow crustal level.-from Authors

Bacon, C. R.; Macdonald, R.; Smith, R. L.; Baedecker, P. A.

1981-01-01

31

Time-dependent seismic tomography of the Coso geothermal area, 1996-2004  

Microsoft Academic Search

Local-earthquake tomographic images were;\\u000acalculated for each of the years 1996 - 2004 using;\\u000aarrival times from the U.S. Navys permanent;\\u000aseismometer network at the Coso geothermal area,;\\u000aCalifornia. The results show irregular strengthening;\\u000awith time of the wave-speed ratio VP\\/VS at shallow;\\u000adepths. These changes result predominately from;\\u000aprogressive relative increase in VS with respect to VP,;\\u000aand could

Bruce R. Julian; Gillian R. Foulger; Keith Richards-Dinger; Francis Monastero

2006-01-01

32

Hot Flashes  

MedlinePLUS

Hot flashes Basics In-Depth Multimedia Expert Answers Resources Reprints A single copy of this article may be reprinted for personal, noncommercial use only. Hot flashes By Mayo Clinic staff Original Article: http:// ...

33

Seismic Monitoring of EGS Tests at the Coso Geothermal Area, California, Using Accurate MEQ Locations and Full Moment Tensors, (Final Report supplement 2).  

National Technical Information Service (NTIS)

We studied high-resolution relative locations and full moment tensors of microearthquakes (MEQs) occurring before, during and following Enhanced Geothermal Systems (EGS) experiments in two wells at the Coso geothermal area, California. The objective was t...

B. R. Julian F. Monastero G. R. Foulger

2008-01-01

34

Residence, resorption and recycling of zircons in Devils Kitchen rhyolite, Coso Volcanic Field, California  

USGS Publications Warehouse

Zircons from the Devils Kitchen rhyolite in the Pleistocene Coso Volcanic field, California have been analyzed by in situ Pb/U ion microprobe (SHRIMP-RG) and by detailed cathodoluminescence imaging. The zircons yield common-Pb-corrected and disequilibrium-corrected 206Pb/238U ages that predate a previously reported K-Ar sanidine age by up to 200 kyr, and the range of ages exhibited by the zircons is also approximately 200 kyr. Cathodoluminescence imaging indicates that zircons formed in contrasting environments. Most zircons are euhedral, and a majority of the zircons are weakly zoned, but many also have anhedral, embayed cores, with euhedral overgrowths and multiple internal surfaces that are truncated by later crystal zones. Concentrations of U and Th vary by two orders of magnitude within the zircon population, and by 10-20 times between zones within some zircon crystals, indicating that zircons were transferred between contrasting chemical environments. A zircon saturation temperature of ???750??C overlaps within error a previously reported phenocryst equilibration temperature of 740 ?? 25??C. Textures in zircons indicative of repeated dissolution and subsequent regrowth are probably caused by punctuated heating by mafic magma input into rhyolite. The overall span of ages and large variation in U and Th concentrations, combined with calculated zircon saturation temperatures and resorption times, are most compatible with crystallization in magma bodies that were emplaced piecemeal in the crust at Coso over 200 kyr prior to eruption, and that were periodically rejuvenated or melted by subsequent basaltic injections. ?? Oxford University Press 2004; all rights reserved.

Miller, J. S.; Wooden, J. L.

2004-01-01

35

Distribution of quaternary rhyolite dome of the Coso Range, California: Implications for extent of the geothermal anomaly  

Microsoft Academic Search

Thirty-eight separate domes and flows of phenocryst-poor, high-silica rhyolite of similar major element chemical composition were erupted over the past 1 m.y. from vents arranged in a crudely S-shaped array atop a granitic horst in the Coso Range, California. Most of the extrusions are probably less than about 0.3 m.y. old. The area is one of Quaternary basaltic volcanism and

Charles R. Bacon; Wendell A. Duffield; Kazuaki Nakamura

1980-01-01

36

Hot Groups.  

ERIC Educational Resources Information Center

|Collaborators sparked by creative ideas and obsessed by a common task may not realize they're part of a "hot group"--a term coined by business professors Harold J. Leavitt and Jean Lipman-Blumen. Spawned by group decision making and employee empowerment, hot groups can flourish in education settings. They're typically small, short lived, and goal…

Vail, Kathleen

1996-01-01

37

Chemical and isotopic characteristics of the coso east flankhydrothermal fluids: implications for the location and nature of the heatsource  

SciTech Connect

Fluids have been sampled from 9 wells and 2 fumaroles fromthe East Flank of the Coso hydrothermal system with a view toidentifying, if possible, the location and characteristics of the heatsource inflows into this portion of the geothermal field. Preliminaryresults show that there has been extensive vapor loss in the system, mostprobably in response to production. Wells 38A-9, 51-16 and 83A-16 showthe highest CO2-CO-CH4-H2 chemical equilibration temperatures, rangingbetween 300-340oC, and apart from 38A-9, the values are generally inaccordance with the measured temperatures in the wells. Calculatedtemperatures for the fractionation of 13C between CO2 and CH4 are inexcess of 400oC in fluids from wells 38A-9, 64-16-RD2 and 51A-16,obviously pointing to equilibrium conditions from deeper portions of thereservoir. Given that the predominant reservoir rock lithologies in theCoso system are relatively silicic (granitic to dioritic), the isotopicsignatures appear to reflect convective circulation and equilibrationwithin rocks close to the plastic-brittle transition. 3He/4He signatures,in conjunction with relative volatile abundances in the Coso fluids,point to a possibly altered mantle source for the heat sourcefluids.

Christenson, B.W.; Kennedy, B.M.; Adams, M.C.; Bjornstad, S.C.; Buck, C.

2007-01-08

38

Hot water, hot rocks, hot science  

Microsoft Academic Search

Of the numerous energy sources, several important ones come from deep inside the earth. Coal, oil, and natural gas have formed over time through the interaction of enormous pressures and temperatures on organic material. Geothermal energy - steam and hot water - is also a product of these subsurface forces. Even the raw material for nuclear energy, uranium, comes from

Wesolowski

1995-01-01

39

Integrated mineralogical and fluid inclusion study of the Coso geothermal systems, California  

SciTech Connect

Coso is one of several high-temperature geothermal systems on the margins of the Basin and Range province that is associated with recent volcanic activity. This system, which is developed entirely in fractured granitic and metamorphic rocks, consists of a well-defined thermal plume that originates in the southern part of the field and then flows upward and laterally to the north. Fluid inclusion homogenization temperatures and salinities demonstrate that cool, low salinity ground waters were present when the thermal plume was emplaced. Dilution of the thermal waters occurred above and below the plume producing strong gradients in their compositions. In response to heating and mixing, clays and carbonate minerals precipitated, sealing the fractures along the margins of the reservoir and strongly influencing its geometry. The alteration mineralogy varies systematically with depth and temperature. Based on the clay mineralogy, three zones can be recognized: the smectite zone, the illite-smectite zone, and the illite zone. The smectite zone thickens from the north to south and is characterized by smectite, kaolin, stilbite and a variety of carbonate minerals. The illite-smectite zone contains mixed-layer clays and also thickens to the south. The deepest zone (the illite zone) contains illite, chlorite, epidote, and wairakite. Quartz and calcite veins occur in all three zones. Comparison of mineral and fluid inclusion based temperatures demonstrates that cooling has occurred along the margins of the thermal system but that the interior of the system is still undergoing heating.

Lutz, Susan J.; Moore, Joseph N.; Copp, John F.

1996-01-24

40

Four-dimensional tomography reveals changes in structure 1996 - 2002 at the Coso geothermal area, California  

NASA Astrophysics Data System (ADS)

The Coso geothermal area, at the southern end of Owens Valley in eastern California, has been commercially exploited for electricity generation for more than a decade. Seismic activity in the area is monitored by a network of three-component digital borehole seismometers operated by the US Navy, and several thousand locatable earthquakes occur each year. This situation is ideal for Local Earthquake Tomography. Inversions for three-dimensional Vp and Vp/Vs structure with resolution of 2 km horizontally and 1 km vertically show that between 1996 and 2002 the Vp/Vs ratio decreased at depths shallower than 2 km below the surface, primarily because of an increase in Vs. This change might be caused by either drying of the rock matrix or decrease in the pore pressure. Time-varying tomography of this kind, previously applied to Long Valley caldera and The Geysers geothermal field, provides a method of monitoring physical changes such as fluid depletion in volcanoes and exploited geothermal reservoirs.

Julian, B. R.; Foulger, G. R.; Monastero, F. C.; Richards-Dinger, K.

2003-12-01

41

Hot Canyon  

ScienceCinema

This historical film footage, originally produced in the early 1950s as part of a series by WOI-TV, shows atomic research at Ames Laboratory. The work was conducted in a special area of the Laboratory known as the "Hot Canyon."

42

Hot Tickets  

ERIC Educational Resources Information Center

|This article describes the highlights of this year's BookExpo America (BEA) held at the Los Angeles Convention Center. The attendees at BEA had not minded that the air was recycled, the lighting was fluorescent, and the food was bad. The first hot book sighting came courtesy of Anne Rice. Michelle Moran, author of newly published novel, "The…

Fox, Bette-Lee; Hoffert, Barbara; Kuzyk, Raya; McCormack, Heather; Williams, Wilda

2008-01-01

43

HOT AIR  

NSDL National Science Digital Library

HOT AIR -- The graphical home page of THE ANNALS OF IMPROBABLE RESEARCH FROM MIT provides a different look at scientific research. Check out a schedule of AIR events, an art gallery, and SharewAIR--an interactive and up-to-the-minute moderated forum.

44

Accessory mineral U-Th-Pb ages and 40Ar/39Ar eruption chronology, and their bearing on rhyolitic magma evolution in the Pleistocene Coso volcanic field, California  

NASA Astrophysics Data System (ADS)

We determined Ar/Ar eruption ages of eight extrusions from the Pleistocene Coso volcanic field, a long-lived series of small volume rhyolitic domes in eastern California. Combined with ion-microprobe dating of crystal ages of zircon and allanite from these lavas and from granophyre geothermal well cuttings, we were able to track the range of magma-production rates over the past 650 ka at Coso. In ?230 ka rhyolites we find no evidence of protracted magma residence or recycled zircon (or allanite) from Pleistocene predecessors. A significant subset of zircon in the ~85 ka rhyolites yielded ages between ~100 and 200 Ma, requiring that generation of at least some rhyolites involves material from Mesozoic basement. Similar zircon xenocrysts are found in an ~200 ka granophyre. The new age constraints imply that magma evolution at Coso can occur rapidly as demonstrated by significant changes in rhyolite composition over short time intervals (?10’s to 100’s ka). In conjunction with radioisotopic age constraints from other young silicic volcanic fields, dating of Coso rhyolites highlights the fact that at least some (and often the more voluminous) rhyolites are produced relatively rapidly, but that many small-volume rhyolites likely represent separation from long-lived mushy magma bodies.

Simon, Justin I.; Vazquez, Jorge A.; Renne, Paul R.; Schmitt, Axel K.; Bacon, Charles R.; Reid, Mary R.

2009-10-01

45

Accessory mineral U-Th-Pb ages and 40Ar/39Ar eruption chronology, and their bearing on rhyolitic magma evolution in the Pleistocene Coso volcanic field, California  

USGS Publications Warehouse

We determined Ar/Ar eruption ages of eight extrusions from the Pleistocene Coso volcanic field, a long-lived series of small volume rhyolitic domes in eastern California. Combined with ion-microprobe dating of crystal ages of zircon and allanite from these lavas and from granophyre geothermal well cuttings, we were able to track the range of magma-production rates over the past 650 ka at Coso. In ??? 230 ka rhyolites we find no evidence of protracted magma residence or recycled zircon (or allanite) from Pleistocene predecessors. A significant subset of zircon in the ???85 ka rhyolites yielded ages between ???100 and 200 Ma, requiring that generation of at least some rhyolites involves material from Mesozoic basement. Similar zircon xenocrysts are found in an ???200 ka granophyre. The new age constraints imply that magma evolution at Coso can occur rapidly as demonstrated by significant changes in rhyolite composition over short time intervals (???10's to 100's ka). In conjunction with radioisotopic age constraints from other young silicic volcanic fields, dating of Coso rhyolites highlights the fact that at least some (and often the more voluminous) rhyolites are produced relatively rapidly, but that many small-volume rhyolites likely represent separation from long-lived mushy magma bodies. ?? The Author(s) 2009.

Simon, J. I.; Vazquez, J. A.; Renne, P. R.; Schmitt, A. K.; Bacon, C. R.; Reid, M. R.

2009-01-01

46

Time-dependent seismic tomography and its application to the Coso geothermal area, 1996-2006  

SciTech Connect

Measurements of temporal changes in Earth structure are commonly determined using localearthquake tomography computer programs that invert multiple seismic-wave arrival time data sets separately and assume that any differences in the structural results arise from real temporal variations. This assumption is dangerous because the results of repeated tomography experiments would differ even if the structure did not change, simply because of variation in the seismic ray distribution caused by the natural variation in earthquake locations. Even if the source locations did not change (if only explosion data were used, for example), derived structures would inevitably differ because of observational errors. A better approach is to invert multiple data sets simultaneously, which makes it possible to determine what changes are truly required by the data. This problem is similar to that of seeking models consistent with initial assumptions, and techniques similar to the “damped least squares” method can solve it. We have developed a computer program, dtomo, that inverts multiple epochs of arrival-time measurements to determine hypocentral parameters and structural changes between epochs. We shall apply this program to data from the seismically active Coso geothermal area, California, in the near future. The permanent network operated there by the US Navy, supplemented by temporary stations, has provided excellent earthquake arrival-time data covering a span of more than a decade. Furthermore, structural change is expected in the area as a result of geothermal exploitation of the resource. We have studied the period 1996 through 2006. Our results to date using the traditional method show, for a 2-km horizontal grid spacing, an irregular strengthening with time of a negative VP/VS anomaly in the upper ~ 2 km of the reservoir. This progressive reduction in VP/VS results predominately from an increase of VS with respect to VP. Such a change is expected to result from effects of geothermal operations such as decreasing fluid pressure and the drying of argillaceous minerals such as illite.

Julian, B.R.; G.R. Foulger; F. Monastero

2008-04-01

47

Time-dependent Seismic Tomography of the Coso Geothermal Area, 1996-2006  

NASA Astrophysics Data System (ADS)

Measurements of temporal changes in Earth structure are commonly determined using local earthquake tomography computer programs that invert multiple seismic-wave arrival time data sets separately and assume that any differences in the structural results arise from real temporal variations. Such an assumption is dangerous because the results of repeated tomography experiments would differ even if the structure did not change, simply because of variation in the seismic ray distribution caused by the natural variation in earthquake locations. Even if the source locations did not change (if only explosion data were used, for example), derived structures would inevitably differ because of observational errors. A much better approach is to invert multiple data sets simultaneously, which makes it possible to determine what changes are truly required by the data. This problem is similar to that of seeking models consistent with initial assumptions, and methods similar to "damped least squares" can solve it. We are developing such a program, dtomo. This program inverts multiple epochs of arrival-time measurements for hypocentral parameters and structural change in the inter-epoch period. We are applying this work to data from the seismically active Coso geothermal area, California. The permanent network operated there by the US Navy, supplemented by temporary stations, provides excellent earthquake arrival-time data. Furthermore, structural change is expected in the area as a result of geothermal exploitation of the resource. We have studied the period 1996 through 2006. Our results show, for a 2-km horizontal grid spacing, an irregular strengthening with time of a negative Vp/Vs anomaly in approximately the upper 2 km of the reservoir. This progressive reduction in Vp/Vs results predominately from a increase of Vs with respect to Vp. Such a change is expected to result from effects of geothermal operations such as decreasing fluid pressure and the drying of argillaceous minerals such as illite.

Foulger, G. R.; Julian, B. R.; Monastero, F. C.

2007-12-01

48

Monitoring microearthquake activity and structure changes at the Coso geothermal area  

NASA Astrophysics Data System (ADS)

The Coso geothermal area, at the southern end of Owens Valley in eastern California, has been exploited for electricity generation for more than a decade, during which time a network of three-component digital borehole seismometers operated by the US Navy has monitored seismic activity. The several thousand locatable microearthquakes recorded each year by this network are well suited to using time-dependent crustal structure, hypocenter locations, and moment-tensor focal-mechanisms to monitor changes caused by production and by reservoir-stimulation experiments. Local-earthquake tomography results reported in 2003 show that between 1996 and 2002 the Vp/Vs ratio decreased in the uppermost 2 km, primarily because of an increase in Vs. This change might be caused by either drying of the rock matrix or a decrease in pore pressure. More detailed tomography, including all years from 1996 to 2003 and having improved horizontal resolution (1 km), now shows that this change occurred primarily in the most recent few years. Locating microearthquakes within the geothermal field by applying high-resolution relative relocation methods (e.g. Waldhauser and Ellsworth, 2000; Richards-Dinger and Shearer, 2000) to arrival-time differences determined by waveform cross-correlation reduces location errors by an order of magnitude (from 100s of meters to 10s of meters). Examples from reservoir-stimulation experiments in 2003 and 2004, when 14 portable seismometers supplemented the permanent seismic network, clearly delineate small structures upon which microearthquakes occur. High-resolution hypocenters are valuable supplements to complete moment-tensor earthquake mechanisms determined from body-wave amplitude ratios measured using the enlarged seismometer network, and help to constrain the physical processes occurring within the geothermal reservoirs better than either data type alone can do.

Julian, B. R.; Foulger, G. R.; Richards-Dinger, K.

2004-12-01

49

Seismic Characterisation of Hydraulic Stimulation Tests at the Coso Geothermal Area, California  

NASA Astrophysics Data System (ADS)

We studied microearthquakes before, during and after fluid injection tests at the Coso geothermal area, California, to map the fractures formed, determine the mode and sense of failure, and characterize the stress cycle associated with injection. Our approach is based on joint interpretation of high-resolution relative earthquake relocations and full earthquake moment tensors. We developed advanced computer programs for this work, which include combining waveform cross-correlation with relative relocation methods, and rigorously assessing the confidence regions for moment tensors derived using linear-programming methods. Using a high-quality permanent network of three-component digital borehole seismometers operated by the US Navy, supplemented by 14 portable three-component digital instruments installed at the surface, we analysed several months of data spanning injection experiments in well 34A-9 in 2004, well 34-9RD2 in 2005, and pre-injection earthquakes near well 46A-19RD. In the case of injection into well 34A-9, the co-injection earthquakes were more numerous, smaller, more explosive and had more horizontal motion, compared with the background earthquakes. Injection modulated the stress orientation in the activated volume for at least two months after injection ceased. In the case of well 34-9RD2, the injection produced spatially coherent seismicity different from the scattered background activity that occurs continuously there. The relocated hypocenters reveal the dimensions and orientation of a well-defined planar structure, 700 m long and 600 m high in the depth range 0.8 to 1.4 km below sea level, striking N 20 degrees E and dipping 75 degrees to the WNW. The moment tensors show that it represented a mode I (opening) crack. The seismicity rate and stress state in the neighborhood of the bottom of the well did not return to its background state for at least two months following the injection.

Julian, B. R.; Foulger, G. R.; Monastero, F. C.

2007-12-01

50

Evolution of vertical permeability in Coso Geothermal Well 58A-10  

NASA Astrophysics Data System (ADS)

Static temperature (T) profiles in geothermal systems record the relative role of conductive and advective heat transport. Under near steady-state conditions these profiles can reveal the long-term average permeability (k) along the T profile to an order of magnitude by solving for the advective component. Well 58A-10 in the undisturbed margin of the Coso Geothermal Field, CA, offers the opportunity to quantify vertical variations in k that provide a critical insight into the life cycle of geothermal systems. This well has three distinct zones of T gradient: a shallow zone from 400-1100 m depth of 100 ° C/km, a near-isothermal intermediate zone from 1100-2900 m, and a basal zone >2900 m of 100 ° C/km. Simple analytical solutions for 1-D heat transport and convective instability can be fit to the observed temperature profiles in the upper two zones. From these solutions the shallow zone requires k<10-17 m2 whereas the intermediate zone requires k>10-13.5 m2, indicating a >103 k difference between these intervals despite similar host rocks and fracture populations. The difference in 1-D, vertical k between the upper two zones appears to arise from the minerals that "heal" fractures as revealed by surface mapping, cuttings and core analysis, and geophysical logs. Initial brittle fracture and frictional slip in low porosity crystalline rocks causes dilation owing to surface roughness along fracture walls, brecciation, and micro-cracking. Yet active precipitation and alteration in geothermal areas implies rapid healing that requires fracture generation or reactivation to maintain k. Fault rocks enriched in neoformed clays minimize dilation during slip and can reduce k to lower than 10-19 m2. Reduced frictional strength in clay-rich faults also promotes their reactivation over the generation of new faults. Since the stability of clays is restricted to relatively low temperature, clay-rich faults are confined to shallow depths. Thus, a fault core enriched in clays at shallow depths becomes a persistent barrier to cross-fault flow that effectively reduces vertical k. Conversely precipitation of calcite or silica dominates healing at greater depth. These minerals retain dilatant behavior during slip that regenerates k as revealed by crack-seal textures. Thus k remains high enough to support convection and isothermal T profiles.

Davatzes, N. C.; Hickman, S. H.

2007-12-01

51

Hot tub folliculitis  

MedlinePLUS

Hot tub folliculitis is an infection of the skin around the lower part of the hair shaft ( ... Hot tub folliculitis is caused by the bacteria Pseudomonas aeruginosa . This form of bacteria survives in hot ...

52

Chiral-selective CoSO4/SiO2 catalyst for (9,8) single-walled carbon nanotube growth.  

PubMed

Electronic and optical properties of single-walled carbon nanotubes (SWCNTs) correlate with their chiral structures. Many applications need chirally pure SWCNTs that current synthesis methods cannot produce. Here, we show a sulfate-promoted CoSO(4)/SiO(2) catalyst, which selectively grows large-diameter (9,8) nanotubes at 1.17 nm with 51.7% abundance among semiconducting tubes and 33.5% over all tube species. After reduction in H(2) at 540 °C, the catalyst containing 1 wt % Co has a carbon yield of 3.8 wt %, in which more than 90% is SWCNT. As compared to other Co catalysts used for SWCNT growth, the CoSO(4)/SiO(2) catalyst is unique with a narrow Co reduction window under H(2) centered at 470 °C, which can be attributed to the reduction of highly dispersed CoSO(4). X-ray absorption spectroscopy (XAS) results suggested the formation of Co particles with an average size of 1.23 nm, which matches the diameter of (9,8) tubes. Density functional theory study indicated that the diameter of structurally stable pure Co particles is scattered, matching the most abundant chiral tubes, such as (6,5) and (9,8). Moreover, the formation of such large Co particles on the CoSO(4)/SiO(2) catalyst depends on sulfur in the catalyst. XAS results showed that sulfur content in the catalyst changes after catalyst reduction at different conditions, which correlates with the change in (n,m) selectivity observed. We proposed that the potential roles of sulfur could be limiting the aggregation of Co atoms and/or forming Co-S compounds, which enables the chiral selectivity toward (9,8) tubes. This work demonstrates that catalysts promoted with sulfur compounds have potentials to be further developed for chiral-selective growth of SWCNTs. PMID:23215361

Wang, Hong; Wei, Li; Ren, Fang; Wang, Qiang; Pfefferle, Lisa D; Haller, Gary L; Chen, Yuan

2012-12-12

53

FDA Hot Topics  

Center for Biologics Evaluation and Research (CBER)

Text VersionFDA Hot Topics. Alan E. Williams, Ph.D. ... January 27-29, 2010. FDA Hot topics. The Office of Blood Research and Review (OBRR), CBER. ... More results from www.fda.gov/downloads/biologicsbloodvaccines/newsevents

54

Hot Weather Tips  

MedlinePLUS

Home > Newsletters > Connections newsletter - Archives > Spring 2003 > HOT Weather Tips E-mail to a Friend Printable Version ©Family Caregiver Alliance We all suffer in hot weather. However, for elderly and disabled ...

55

Locating an active fault zone in Coso geothermal field by analyzing seismic guided waves from microearthquake data  

SciTech Connect

Active fault systems usually provide high-permeability channels for hydrothermal outflow in geothermal fields. Locating such fault systems is of a vital importance to plan geothermal production and injection drilling, since an active fault zone often acts as a fracture-extensive low-velocity wave guide to seismic waves. We have located an active fault zone in the Coso geothermal field, California, by identifying and analyzing a fault-zone trapped Rayleigh-type guided wave from microearthquake data. The wavelet transform is employed to characterize guided-wave's velocity-frequency dispersion, and numerical methods are used to simulate the guided-wave propagation. The modeling calculation suggests that the fault zone is {approx} 200m wide, and has a P wave velocity of 4.80 km/s and a S wave velocity of 3.00 km/s, which is sandwiched between two half spaces with relatively higher velocities (P wave velocity 5.60 km/s, and S wave velocity 3.20 km/s). zones having vertical or nearly vertical dipping fault planes.

SGP-TR-150-16

1995-01-26

56

ITER hot cell  

Microsoft Academic Search

The paper provides an overview of the International Thermonuclear Experimental Reactor (ITER) hot cell system design. The system includes the hot cell proper, required for use both during machine assembly and operations, and the radwaste facility. The hot cell is divided in different areas and equipped with a variety of process and testing equipment. The components and waste streams are

O. Asuar; V. Baulo; T. Fisher; R. Haange; T. Honda; D. Maisonnier; D. Murdoch; C. Ozzano; J. Palmer; J. Sovka; T. Suzuki; A. Tesini; H. Yoshida

2003-01-01

57

Solar hot water heater  

Microsoft Academic Search

A solar hot water heater includes an insulated box having one or more hot water storage tanks contained inside and further having a lid which may be opened to permit solar radiation to heat a supply of water contained within the one or more hot water storage tanks. A heat-actuated control unit is mounted on an external portion of the

1982-01-01

58

Modelling Hot Air Balloons.  

ERIC Educational Resources Information Center

|A macroscopic way of modeling hot air balloons using a Newtonian approach is presented. Misleading examples using a car tire and the concept of hot air rising are discussed. Pressure gradient changes in the atmosphere are used to explain how hot air balloons work. (KR)|

Brimicombe, M. W.

1991-01-01

59

Seismic monitoring of EGS tests at the Coso Geothermal area, California, using accurate MEQ locations and full moment tensors  

SciTech Connect

We studied high-resolution relative locations and full moment tensors of microearthquakes (MEQs) occurring before, during and following Enhanced Geothermal Systems (EGS) experiments in two wells at the Coso geothermal area, California. The objective was to map new fractures, determine the mode and sense of failure, and characterize the stress cycle associated with injection. New software developed for this work combines waveform crosscorrelation measurement of arrival times with relative relocation methods, and assesses confidence regions for moment tensors derived using linearprogramming methods. For moment tensor determination we also developed a convenient Graphical User Interface (GUI), to streamline the work. We used data from the U.S. Navy’s permanent network of three-component digital borehole seismometers and from 14 portable three-component digital instruments. The latter supplemented the permanent network during injection experiments in well 34A-9 in 2004 and well 34-9RD2 in 2005. In the experiment in well 34A-9, the co-injection earthquakes were more numerous, smaller, more explosive and had more horizontal motion, compared with the pre-injection earthquakes. In the experiment in well 34-9RD2 the relocated hypocenters reveal a well-defined planar structure, 700 m long and 600 m high in the depth range 0.8 to 1.4 km below sea level, striking N 20° E and dipping at 75° to the WNW. The moment tensors show that it corresponds to a mode I (opening) crack. For both wells, the perturbed stress state near the bottom of the well persisted for at least two months following the injection.

Foulger, G.R.; B.R. Julian, B.R.; F. Monastero

2008-04-01

60

Cosmogenic 3He and 21Ne production rates calibrated against 10Be in minerals from the Coso volcanic field  

NASA Astrophysics Data System (ADS)

This study calibrates the production rate of cosmogenic 3He in pyroxene, olivine, garnet, zircon and apatite as well as 21Ne in quartz and pyroxene against the known production rate of 10Be in quartz. The Devil's Kitchen rhyolite from the Coso volcanic field in southeastern California (elev. ~ 1300 m) was chosen for this study due to its young age (~ 610 ka) and diverse mineral assemblage. Based on 10Be, our two rhyolite samples have apparent exposure ages of ~ 49 and 93 ka, indicating substantial erosion after eruption. Combining data from the two samples, we estimate sea level high latitude 3He spallation production rates of 145 ± 11, 141 ± 16, and 144 ± 30 at g - 1 a - 1 (2 ?) for pyroxene, olivine and spessartine garnet respectively. For zircon and apatite, we estimate apparent 3He spallation production rates of 114 ± 8 and 149 ± 28 at g - 1 a - 1 (2 ?) respectively. The rates for zircon and apatite are reported as apparent production rates because we do not explicitly address the redistribution of spallation produced 3He from adjacent minerals. These estimates quantitatively account for production of 3He from both cosmogenic and radiogenic neutron reactions on 6Li within the analyzed phases and also implanted from nuclear reactions in neighboring minerals; the high U, Th and Li content of this rhyolite provides a particularly rigorous test of this correction. We estimate 21Ne production rates of 17.7 ± 1.6 and 34.1 ± 3.2 at g - 1 a - 1 (2 ?) in quartz and pyroxene (Fe/Mg = 0.7 by mass) respectively. Although high U and Th contents create the potential for significant production of nucleogenic 21Ne, this component is small due to the young eruption age of the rhyolite.

Amidon, William H.; Rood, Dylan H.; Farley, Kenneth A.

2009-04-01

61

Use of U and Th Decay-Series Disequilibrium to Characterize Geothermal Systems: An Example from the Coso Geothermal System  

NASA Astrophysics Data System (ADS)

Uranium and thorium decay series isotopes were measured in fluids and solids in the Coso geothermal system to assess the utility and constrain the limitations of the radioisotopic approach to the investigation of rock-water interaction. Fluid radioisotope measurements indicate substantial kilometer-scale variability in chemistry. Between 1988 and 1990, radium isotope activity ratios indicate temporal variability, which is exhibited by apparent mixing relationships observed as a function of time for single wells. Activity ratios of Ra-224/Ra-226 and Ra- 228/Ra-226, and the processes that contribute and remove these radionuclide to and from the fluids, constrain residence times of fluids and may help constrain fluid velocities in the geothermal system. Activity ratios of Ra- 224/Ra-226 > ten were measured. In groundwater and geothermal systems ratios of Ra-224/Ra-226 > ten are limited to zones of thermal upwelling or very young (days to weeks) waters in mountainous areas. Rn-222 results indicate that radon is also an effective tracer for steam velocities within the geothermal system. Analysis of carbon dioxide and Rn-222 data indicates that the residence time of steam (time since separation from the liquid) is short (probably less than four days). Estimates of fluid velocities derived from Rn-222 and radium isotopic measurements are within an order of magnitude of velocities derived from a fluorescein tracer test. Both Rn-222 and Ra-224 activities are higher in single-phase fluids in the northwest as compared to the southeast, indicating a higher rock-surface-area/water-volume ratio in the northwest. Thus, measurements of short-lived radioisotopes and gaseous phase constituents can constrain processes and characteristics of geothermal systems that are usually difficult to constrain (e.g., surface area/volume, residence times). The NRC staff views expressed herein are preliminary and do not constitute a final judgment or determination of the matters addressed or of the acceptability of a license application for a geologic repository at Yucca Mountain.

Leslie, B. W.; Hammond, D.

2007-12-01

62

Lead and strontium isotopic evidence for crustal interaction and compositional zonation in the source regions of Pleistocene basaltic and rhyolitic magmas of the Coso volcanic field, California  

USGS Publications Warehouse

The isotopic compositions of Pb and Sr in Pleistocene basalt, high-silica rhyolite, and andesitic inclusions in rhyolite of the Coso volcanic field indicate that these rocks were derived from different levels of compositionally zoned magmatic systems. The 2 earliest rhyolites probably were tapped from short-lived silicic reservoirs, in contrast to the other 36 rhyolite domes and lava flows which the isotopic data suggest may have been leaked from the top of a single, long-lived magmatic system. Most Coso basalts show isotopic, geochemical, and mineralogic evidence of interaction with crustal rocks, but one analyzed flow has isotopic ratios that may represent mantle values (87Sr/86Sr=0.7036,206Pb/204Pb=19.05,207Pb/204Pb=15.62,208Pb/204Pb= 38.63). The (initial) isotopic composition of typical rhyolite (87Sr/86Sr=0.7053,206Pb/204Pb=19.29,207Pb/204Pb= 15.68,208Pb/204Pb=39.00) is representative of the middle or upper crust. Andesitic inclusions in the rhyolites are evidently samples of hybrid magmas from the silicic/mafic interface in vertically zoned magma reservoirs. Silicic end-member compositions inferred for these mixed magmas, however, are not those of erupted rhyolite but reflect the zonation within the silicic part of the magma reservoir. The compositional contrast at the interface between mafic and silicic parts of these systems apparently was greater for the earlier, smaller reservoirs. ?? 1984 Springer-Verlag.

Bacon, C. R.; Kurasawa, H.; Delevaux, M. H.; Kistler, R. W.; Doe, B. R.

1984-01-01

63

Hot-wire anemometry  

Microsoft Academic Search

A brief historical survey of hot-wire anemometry is presented and questions of hot-wire response are investigated, taking into account sensor properties, steady-heat-loss laws, the dynamic response of the wires, the sensitivity coefficients of the wires, the characteristics of a wire of finite length, the spatial resolution of hot wires, and the aerodynamic perturbations of the probes. A description of electronic

G. Comte-Bellot

1976-01-01

64

HotBot  

NSDL National Science Digital Library

HotBot, a service of HotWired Ventures, uses the Inktomi search engine as the heart of its new Internet search service. It claims to index the full text contents of 50 million Web pages, as well as Usenet news and mailing lists. This would make it the largest search engine on the Internet. HotBot supports Boolean AND/OR/NOT, and phrase searching. It provides relevance feedback with retrieval. It also supports chronological, domain, and geographic searches, as well as media type searches such as Java, VRML, and Acrobat. HotBot is a public "beta" site and encourages feedback and bug reports.

65

The Earth's Hot Spots.  

ERIC Educational Resources Information Center

Hot spots are isolated areas of geologic activity where volcanic eruptions, earthquakes, and upwelling currents occur far from plate boundaries. These mantle plumes are relatively stable and crustal plates drift over them. The nature and location of hot spots (with particular attention to the Hawaiian Islands and Iceland) are discussed. (DH)

Vink, Gregory E.; And Others

1985-01-01

66

Household hot water systems  

Microsoft Academic Search

An arrangement for combination with the conventional hot water system of a house or building in which the water is conventionally heated and stored in a tank, the arrangement comprising a solar energy panel (at an upper level) with a thermostatic valve and a supplementary cold water tank, connected into the system in such a way that hot water is

Tacchi

1983-01-01

67

Solar hot water generator  

Microsoft Academic Search

A solar hot water generating system is disclosed which comprises a vertically pivotable heat exchanger automatically pivotable by means of a timer-actuated electric motor. The heat exchanger is fluidly connected to an insulated storage tank which retains the thermal values of the heated fluid. The system is adapted to provide hot water for domestic and industrial uses, such as heating,

1982-01-01

68

Hot air solar engine  

Microsoft Academic Search

A hot air solar engine has two heat engines at opposing ends of a common piston assembly to provide alternate cooperative expansion and compression action. Each of the heat engines has a compressor and an expander wherein a single dual-diameter piston head serves as the piston portion of each. The hot air solar engine further includes a solar collector having

1983-01-01

69

Multipurpose Reprocessing Hot Cell.  

National Technical Information Service (NTIS)

A multipurpose hot cell for use in the new head end system is described. The use of a hot cell as part of the routine fuel charging procedure provides considerable flexibility in handling a wide variety of fuel sizes up to 25,000 lb.

R. D. Fletcher

1975-01-01

70

What Is Hot Yoga (Bikram)?  

MedlinePLUS

... reprinted for personal, noncommercial use only. What is hot yoga? By Mayo Clinic staff Original Article: http:// ... e-mail address Sign up Question What is hot yoga? What’s different about hot yoga versus other ...

71

CSA Hot Topics Series  

NSDL National Science Digital Library

The Hot Topics series provides a free sampling of the resources in Cambridge Scientific Abstracts (CSA) and the Internet Database Service (IDS). The 30 topics span subjects in the humanities, engineering, environmental policy, and medicine. Each Hot Topic gives an overview of the subject, key citations with abstracts, a list of Websites, a glossary, a comment form so that users can correspond with the editors, and a "source" section, which explains from which of CSA's paid services the resources were culled. The latest hot topic is MicroElectroMechanical systems (MEMS), "small integrated devices or systems that combine electrical and mechanical components."

72

Jupiter's Hot Spots  

NASA Video Gallery

NASA postdoctoral fellow David Choi discusses his study of dark features in Jupiter's atmosphere called "hot spots," and their connection to large-scale atmospheric waves. › Download video in HD formats       › Related story

gsfcvideo

2013-03-13

73

Hot Dry Rock Technology.  

National Technical Information Service (NTIS)

This session at the Geothermal Energy Program Review X: Geothermal Energy and the Utility Market consisted of four presentations: 'Hot Dry Rock - Summary' by George P. Tennyson, Jr.; 'HDR Opportunities and Challenges Beyond the Long Term Flow Test' by Dav...

2005-01-01

74

The Hot Tub Mystery  

NSDL National Science Digital Library

This case study sets up a mystery and asks students to solve it using science: why was the couple found dead in their hot tub? The material asks students to connect seemingly unrelated factors, such as blood pressure, hot water and alcohol. The material would be most appropriate for lower level undergraduate students. The case study and teaching notes may be downloaded in PDF format. The site also includes a section for instructor feedback where general comments may be read and contributed.

House, Herbert

2011-01-06

75

Geothermal hot water system  

SciTech Connect

Geothermal hot water system including a hot water tank and a warm water tank which are heated independently of each other by a close loop freon system. The closed loop freon system includes a main condenser which heats water for the warm water tank and a super-heated condenser which heats water for the hot water tank, and where the freon passes through a water evaporator which is heated by water such as from a well or other suitable source. The water evaporator in the closed loop freon system passes the water through but no environmental change to the water. An electrical circuit including aquastats in the warm water tank connected therethrough controls operation of the closed loop freon system including respective pumps on the super-heated condenser and main condenser for pumping water. Pumps pump water through the main condenser for the warm tank and through the super-heated condenser for the hot tank. The system provides for energy conservation in that the head pressure of the compressor is kept in the lower operating ranges as determined by the discharge flow of the main condenser which varies by the head pressure and temperature flow control which varies by temperature. The geothermal hot water system uses a least amount of energy in heating the water in the hot tank as well as the warm tank.

Dittell, E.W.

1983-05-10

76

Automatic hot water recovery system  

Microsoft Academic Search

A heat recovery system recovers hot water to an insulated tank through reciprocally variable volume chambers which are biased to draw water from hot water lines when the pressure throughout the system is equalized. One-way valving means permits continuous water flow when desired through the hot water tank to the hot water outlet. In a specific embodiment, bias is effected

Haws

1985-01-01

77

Fault block kinematics at a releasing stepover of the Eastern California shear zone: Partitioning of rotation style in and around the Coso geothermal area and nascent metamorphic core complex  

Microsoft Academic Search

Pliocene lavas and sediments of Wild Horse Mesa in the Coso Range, CA exhibit clockwise vertical-axis rotation of fault-bounded blocks. This indicates localization of one strand of the Eastern California shear zone\\/Walker Lane Belt within a large-scale, transtensional, dextral, releasing stepover. We measured rotations paleomagnetically relative to two different reference frames. At two localities we averaged secular variation through sedimentary

Christopher J. Pluhar; Robert S. Coe; Jonathan C. Lewis; Francis C. Monastero; Jonathan M. G. Glen

2006-01-01

78

The hot list strategy.  

SciTech Connect

Experimentation strongly suggests that, for attacking deep questions and hard problems with the assistance of an automated reasoning program, the more effective paradigms rely on the retention of deduced information. A significant obstacle ordinarily presented by such a paradigm is the deduction and retention of one or more needed conclusions whose complexity sharply delays their consideration. To mitigate the severity of the cited obstacle, I formulated and feature in this article the hot list strategy. The hot list strategy asks the researcher to choose, usually from among the input statements characterizing the problem under study, one or more statements that are conjectured to play a key role for assignment completion. The chosen statements--conjectured to merit revisiting, again and again--are placed in an input list of statements, called the hot list. When an automated reasoning program has decided to retain a new conclusion C--before any other statement is chosen to initiate conclusion drawing--the presence of a nonempty hot list (with an appropriate assignment of the input parameter known as heat) causes each inference rule in use to be applied to C together with the appropriate number of members of the hot list. Members of the hot list are used to complete applications of inference rules and not to initiate applications. The use of the hot list strategy thus enables an automated reasoning program to briefly consider a newly retained conclusion whose complexity would otherwise prevent its use for perhaps many CPU-hours. To give evidence of the value of the strategy, I focus on four contexts: (1) dramatically reducing the CPU time required to reach a desired goal, (2) finding a proof of a theorem that had previously resisted all but the more inventive automated attempts, (3) discovering a proof that is more elegant than previously known, and (4) answering a question that had steadfastly eluded researchers relying on an automated reasoning program. I also discuss a related strategy, the dynamic hot list strategy (formulated by my colleague W. McCune), that enables the program during a run to augment the contents of the hot list. In the Appendix, I give useful input files and interesting proofs. Because of frequent requests to do so, I include challenge problems to consider, commentary on my approach to experimentation and research, and suggestions to guide one in the use of McCunes automated reasoning program OTTER.

Wos, L.; Pieper, G. W.; Mathematics and Computer Science

1999-01-01

79

Beppu hot springs  

SciTech Connect

Beppu is one of the largest hot springs resorts in Japan. There are numerous fumaroles and hot springs scattered on a fan-shaped area, extending 5 km (3.1 miles) from east to west and 8 km (5.0 miles) from north to south. Some of the thermal manifestations are called {open_quotes}Jigoku (Hells){close_quotes}, and are of interest to visitors. The total amount of discharged hot springs water is estimated to be 50,000 ton/day (9,200 gpm) indicating a huge geothermal system. The biggest hotel in Beppu (Suginoi Hotel) installed a 3-MW geothermal power plant in 1981 to generate electricity for its own private use.

Taguchi, Schihiro [Fukuoka Univ. (Japan); Itoi, Ryuichi [Kyushu Univ., Kasuga (Japan); Yusa, Yuki [Kyoto Univ., Beppu (Japan)

1996-05-01

80

Hot piston ring tests  

SciTech Connect

As part of the DOE/NASA Automotive Stirling Engine Project, tests were made at NASA Lewis Research Center to determine whether appendix gap losses could be reduced and Stirling engine performance increased by installing an additional piston ring near the top of each piston dome. An MTI-designed upgraded Mod I Automotive Stirling Engine was used for these tests. Unlike the conventional rings at the bottom of the piston, these rings operated in a high temperature environment (700/sup 0/C). Because of this, we called them ''hot-rings.'' It was necessary that they be made of a high temperature alloy (Stellite 6B) and that a high temperature solid lubricant coating (NASA Lewis-developed PS-200) be applied to the cylinder walls. Engine tests were run at 5, 10, and 15 MPa operating pressure over a range of operating speeds. Tests were run both with the hot-rings in place and without them to pro-side a baseline for comparison. Although budget and schedule restrictions severely limited the testing, the minimum data to assess the potential of both the hot-rings and high temperature low friction coating was obtained. Results indicated a slight increase in power and efficiency with the hot-rings over the baseline configuration. This increase was over and above the friction loss introduced by the hot-rings. Seal leakage measurements showed a significant reduction in leakage with the hot-rings in place. In addition, cylinder wall temperature measurements indicated less cylinder heating in the appendix gap area - between the lower piston rings and the hot-ring. Approximately 22.4 hours of ring-on-coating operation were recorded. After the initial break-in period, wear on both the rings and the coating was low. The PS-200 coating seems to offer significant potential for long-term operation at high temperatures. Both the hot-ring and the PS-200 low friction coating show promise and should be pursued further.

Allen, D.J.; Tomazic, W.A.

1987-01-01

81

Hot Talk, Cold Science  

Microsoft Academic Search

One of the hottest topics in climate science is understanding and evaluating the impacts of possible global warming caused by anthropogenic emissions of greenhouse gases. In Hot Talk, Cold Science, S. Fred Singer does not accept global warming. Singer says in his preface, ``The purpose of this book is to demonstrate that the evidence [for global warming] is neither settled,

Robert J. Oglesby

1998-01-01

82

Hot off the Press  

ERIC Educational Resources Information Center

|In the past, the newspaper was one of the world's most used sources of information. Recently, however, its use has declined due to the popularity of cable television and the Internet. Yet the idea of reading the morning paper with a hot cup of coffee holds many warm memories for children who watched their parents in this daily ritual. In this…

Brisco, Nicole D.

2007-01-01

83

Hot corrosion of materials  

Microsoft Academic Search

Alloys and ceramics may experience accelerated corrosion at high temperatures when their surfaces are coated by a thin film of fused salt in an oxidizing environment. Because of their high thermodynamic stabilities, fused alkali sulfates are frequently deposited or condensed onto hot substrates from the combustion product gases or else by the oxidation of heavy metal contaminants in the fuel,

Robert A. Rapp

1990-01-01

84

China's 'Hot Money' Problems.  

National Technical Information Service (NTIS)

Economic conditions in China are of considerable concern to U.S. policy makers, given the potential impact of China's economy on the global and U.S. economy. The recent large inflow of financial capital into China, commonly referred to as 'hot money,' has...

M. F. Martin W. M. Morrison

2008-01-01

85

Hot Dry Rock - Summary  

Microsoft Academic Search

Hot Dry Rock adds a new flexibility to the utilization of geothermal energy. Almost always the approach has been to limit that utilization to places where there is a natural source of water associated with a source of heat. Actually, the result was that steam was mined. Clearly there are much larger heat resources available which lack natural water to

Tennyson; George P. Jr

1992-01-01

86

Hot piston ring tests  

NASA Astrophysics Data System (ADS)

As part of the DOE/NASA Automotive Stirling Engine Project, tests were made at NASA Lewis Research Center to determine whether appendix gap losses could be reduced and Stirling engine performance increased by installing an additional piston ring near the top of each piston dome. An MTI-designed upgraded Mod I Automotive Stirling Engine was used. Unlike the conventional rings at the bottom of the piston, these hot rings operated in a high temperature environment (700 C). They were made of a high temperature alloy (Stellite 6B) and a high temperature solid lubricant coating (NASA Lewis-developed PS-200) was applied to the cylinder walls. Engine tests were run at 5, 10, and 15 MPa operating pressure over a range of operating speeds. Tests were run both with hot rings and without to provide a baseline for comparison. Minimum data to assess the potential of both the hot rings and high temperature low friction coating was obtained. Results indicated a slight increase in power and efficiency, an increase over and above the friction loss introduced by the hot rings. Seal leakage measurements showed a significant reduction. Wear on both rings and coating was low.

Allen, David J.; Tomazic, William A.

1987-12-01

87

Zen Hot Dog Molecules  

ERIC Educational Resources Information Center

|Substituted cycloalkanes with one branch illustrating each topic in an instructional unit can serve as summaries or reviews in courses of organic chemistry. The hungry Zen master told the hot dog vendor to make him one with everything. You can do the same for your students.|

Ryan, Dennis

2009-01-01

88

Hot oiling spreadsheet.  

National Technical Information Service (NTIS)

One of the most common oil-field treatments is hot oiling to remove paraffin from wells. Even though the practice is common, the thermal effectiveness of the process is not commonly understood. In order for producers to easily understand the thermodynamic...

A. J. Mansure

1996-01-01

89

What's Hot? What's Not?  

ERIC Educational Resources Information Center

When Goldilocks finds three bowls of porridge at different temperatures in the three bears' house, she accurately assesses the situation and comes up with one of the most recognizable lines in children's literature," This porridge is too hot; this porridge is too cold; aahh, this porridge is just right!" Goldilocks' famous line is a perfect…

Buczynski, Sandy

2006-01-01

90

Hot hands and equilibrium  

Microsoft Academic Search

Past literature suggests that success rates in professional basketball are independent of past performance and this has been interpreted as evidence that the commonly shared belief in Hot Hands (HH) is a cognitive illusion. This is often cited as evidence of biased decision making, even when financial stakes are high. We argue that this interpretation ignores changes in both teams’

Gil Aharoni; Oded H. Sarig

2011-01-01

91

Hot hands and equilibrium  

Microsoft Academic Search

Past literature suggests that success rates in professional basketball are independent of past performance and this has been interpreted as evidence that the commonly shared belief in Hot Hands (HH) is a cognitive illusion. This is often cited as evidence of biased decision making, even when financial stakes are high. We argue that this interpretation ignores changes in both teams’

Gil Aharoni; Oded H. Sarig

2012-01-01

92

Varmgasrensning. (Hot gas cleaning).  

National Technical Information Service (NTIS)

In relation to thermal power plants, the status of hot gas cleaning and the properties of tin oxide and the compounds formed in an impure coal gas are discussed and results of experiments with SnO(sub 2) masses are presented and evaluated. Possible cleani...

D. V. Nielsen P. E. Hoejlund Nielsen I. D. Sigurdardottir H. Christiansen

1993-01-01

93

Kamchatka's thermal hot springs  

NSDL National Science Digital Library

The Kamchatka Peninsula is featured in this website including information on geography, climate, fauna, flora, volcanoes, thermal springs, Valley of Geysers, native people, and options for travel in Kamchatka. This specific page highlights a selection of Kamchatka's hot springs, presenting basic information on temperature ranges, chemical and physical characteristics, surrounding vegetation, and general location.

Kamchatka, Vision O.

94

OECD Focus Hot File  

NSDL National Science Digital Library

In each issue of the Organization for Economic Co-operation and Development (OECD)'s Focus Hot File, recent books and government reports of interest are listed with summaries and contact information. Past listings may be browsed by country in the Focus Compendium, and related publications are hyperlinked throughout.

95

Some Like it Hot  

NSDL National Science Digital Library

NASA Astrobiologist Jack Farmer is featured in this web article that focuses on microrganisms found in Yellowstone hot springs and ocean floor hydrothermal vents. Included within the article are numerous links to concepts, resources, and further readings involving exobiology. and microbiology. Downloadable Quick time videos of a discussion with Farmer and hydrothermal vent activity at the ocean floor are also available.

Bortman, Henry; Magazine, Astrobiology

96

Practical hot oiling and hot watering for paraffin control.  

National Technical Information Service (NTIS)

One of the common oil-field wellbore problems is paraffin deposition. Even though hot oiling or hot watering is usually the first method tried for removing paraffin, few operators appreciate the limitations of ''hot oiling'' and the potential for the flui...

A. J. Mansure K. M. Barker

1994-01-01

97

Hot Tub Rash (Pseudomonas Folliculitis)  

MedlinePLUS

newsletter | contact Share | Hot Tub Rash ( Pseudomonas Folliculitis) Information for adults A A A This image displays follicular elevations of the skin and small pus-filled lesions. Overview Hot tub rash ( Pseudomonas folliculitis) is an infection of ...

98

The hot chocolate effect  

NASA Astrophysics Data System (ADS)

The ''hot chocolate effect'' was investigated quantitatively, using water. If a tall glass cylinder is filled nearly completely with water and tapped on the bottom with a softened mallet one can detect the lowest longitudinal mode of the water column, for which the height of the water column is one-quarter wavelength. If the cylinder is rapidly filled with hot tap water containing dissolved air the pitch of that mode may descend by nearly three octaves during the first few seconds as the air comes out of solution and forms bubbles. Then the pitch gradually rises as the bubbles float to the top. A simple theoretical expression for the pitch ratio is derived and compared with experiment. The agreement is good to within the 10% accuracy of the experiments.

Crawford, Frank S.

1982-05-01

99

Hot fire, cool soil  

NASA Astrophysics Data System (ADS)

Wildfires greatly increase a landscape's vulnerability to flooding and erosion events by removing vegetation and changing soils. Fire damage to soil increases with increasing soil temperature, and, for fires where smoldering combustion is absent, the current understanding is that soil temperatures increase as fuel load and fire intensity increase. Here, however, we show that this understanding that is based on experiments under homogeneous conditions does not necessarily apply at the more relevant larger scale where soils, vegetation, and fire characteristics are heterogeneous. In a catchment-scale fire experiment, soils were surprisingly cool where fuel load was high and fire was hot and, conversely, soils were hot where expected to be cooler. This indicates that the greatest fire damage to soil can occur where fuel load and fire intensity are low rather than high, and has important implications for management of fire-prone areas prior to, during, and after fire events.

Stoof, Cathelijne R.; Moore, Demie; Fernandes, Paulo M.; Stoorvogel, Jetse J.; Fernandes, Ricardo E. S.; Ferreira, António J. D.; Ritsema, Coen J.

2013-04-01

100

THE HOT CHOCOLATE EFFECT  

SciTech Connect

The "hot chocolate effect" was investigated quantitatively, using water. If a tall glass cylinder is filled nearly completely with water and tapped on the bottom with a softened mallet one can detect the lowest longitudinal mode of the water column, for which the height of the water column is one quarter wavelength. If the cylinder is rapidly filled with hot tap water containing dissolved air the pitch of that mode may descend by nearly three octaves during the first few seconds as the air comes out of solution and forms bubbles. Then the pitch gradually rises as the bubbles float to the top. A simple theoretical expression for the pitch ratio is derived and compared with experiment. The agreement is good to within the ten percent accuracy of the experiments.

Crawford, Frank S.

1980-12-01

101

Hot chocolate effect  

SciTech Connect

The ''hot chocolate effect'' was investigated quantitatively, using water. If a tall glass cylinder is filled nearly completely with water and tapped on the bottom with a softened mallet one can detect the lowest longitudinal mode of the water column, for which the height of the water column is one-quarter wavelength. If the cylinder is rapidly filled with hot tap water containing dissolved air the pitch of that mode may descend by nearly three octaves during the first few seconds as the air comes out of solution and forms bubbles. Then the pitch gradually rises as the bubbles float to the top. A simple theoretical expression for the pitch ratio is derived and compared with experiment. The agreement is good to within the 10% accuracy of the experiments.

Crawford, F.S.

1982-05-01

102

Policing Crime Hot Spots  

Microsoft Academic Search

In recent years, crime scholars and practitioners have pointed to the potential benefits of focusing crime prevention efforts\\u000a on crime places. A number of studies suggest that crime is not spread evenly across city landscapes. Rather, there is significant\\u000a clustering of a crime in small places, or “hot spots,” that generate half of all criminal events (Pierce et al., 1988;

Anthony A. Braga

103

The ''hot'' patella  

SciTech Connect

Increased patellar uptake on bone scans is seen quite commonly but the possible or probable etiologies of this finding have not been previously well described. A review of 100 consecutive bone scans showed that the incidence of bilateral ''hot'' patellae is 15%. Identified etiologies include osteoarthritic degenerative disease (35%), fracture, possible metastatic disease, bursitis, Paget's disease, and osteomyelitis. The value of careful history, physical examination, and radiographs is stressed.

Kipper, M.S.; Alazraki, N.P.; Feiglin, D.H.

1982-01-01

104

Hot refueling hazards.  

PubMed

Hot refueling in the special operations community has several potential hazards which can accompany the operation. The MC-130 Panel Operator's (PO) position is located in the exhaust of the number 3 engine, subjecting him to fumes, heat, and exhaust blast. The hypothesis was that time constraints should be implemented to the work load due to heat and carbon monoxide exposure. The hypothesis was confirmed for heat exposure but not for significant carbon monoxide exposure. PMID:2496343

Hammer, D L

1989-03-01

105

Activity and Osmotic Coefficients from the Emf of Liquid-Membrane Cells. VII: Co(ClO 4 ) 2 , Ni(ClO 4 ) 2 , K 2 SO 4 , CdSO 4 , CoSO 4 , and NiSO 4  

Microsoft Academic Search

The activity coefficients of CdSO4 CoSO4, and NiSO4 are determined from the emf of liquid-membrane cells, like those described in the papers I–VI of this series. The activity coefficients of the auxiliary salts Co(ClO4)2, Ni(ClO4)2, and K2SO4, needed to eliminate the problem of extrapolation to infinite dilution of the 2–2 salts, are also measured. CdSO4 CoSO4 and NiSO4 in the

Francesco Malatesta; Laura Carbonaro; Nicolangelo Fanelli; Simone Ferrini; Ambrogio Giacomelli

1999-01-01

106

Quarkonium in Hot Medium  

SciTech Connect

I review recent progress in studying quarkonium properties in hot medium as well as possible consequences for quarkonium production in heavy ion collisions. There has been considerable interest in studying quarkonia in hot medium since the publication of the famous Matsui and Satz paper. It has been argued that color screening in a deconfined QCD medium will suppress the existence of quarkonium states, signaling the formation of a quark-gluon plasma (QGP) in heavy-ion collisions. Although this idea was proposed a long time ago, first principle QCD calculations, which go beyond qualitative arguments, have been performed only recently. Such calculations include lattice QCD determinations of quarkonium correlators; potential model calculations of the quarkonium spectral functions with potentials based on lattice QCD, as well as effective field theory approaches that justify potential models and reveal new medium effects. Spectral properties of heavy quark bound states are important ingredients in modeling of heavy quarkonium production in hot medium as will be discussed later.

Petreczky, P.

2010-08-02

107

PREFACE: Hot Quarks 2004  

NASA Astrophysics Data System (ADS)

Why another conference devoted to ultra-relativistic heavy-ion physics? As we looked around the landscape of the existing international conferences and workshops, we realized that there was not a single one tailored to the people who are most directly involved with the actual research work: students, post-docs, and junior faculty/research scientists. Of course there are schools, but that was not what we had in mind. We wanted a meeting where young researchers could come together to discuss in depth the physics that they are working on without any hindrance. The major conferences have very limited time for discussions which is often shared amongst the most established. This leaves little room for young people to ask their questions and to get the detailed feedback which they deserve and which satisfies their curiosity. A discussion-driven workshop, centering on those without whom there will be no future—that seemed like what was needed. And thus the Hot Quarks workshop was born. The aim of Hot Quarks was to enhance the direct exchange of scientific information among the younger members of the community, from both experiment and theory. Participation was by invitation only in order to emphasize the contributions from junior researchers. This approach makes the workshop unique among the many forums in the field. For young scientists it represented an opportunity for exposure that they would not have had in one of the major conferences. The hope is that this meeting has helped to stimulate the next generation of scientists in our field and, at the same time, strengthened their sense of community. It all came together from 18 24 July 2004, when the 77 participants met at The Inn at Snakedance in the Taos Ski Valley, New Mexico, USA, for the first Hot Quarks workshop. Photograph Participants gather in the sunshine at the foot of the Taos Ski Valley chairlift. By all accounts, Hot Quarks 2004 was a great success. Every participant had the opportunity to present her or his research and we spent an entire week talking physics and having fun from breakfast in the morning until late at night. A symbolic award was instituted for the best presentation at the workshop, dedicated to the memory of Klaus Kinder-Geiger, a sharp and brilliant young theorist who perished in the crash of Swissair Flight 111 on 2 September 1998 off the coast of Nova Scotia. It went to Denesh Molnar from Ohio State University for his outstanding talk on parton coalescence. The organizers wish to extend their gratitude to all participants for the high quality presentations making Hot Quarks 2004 a notable event. We are also very grateful for the superb hospitality of the staff of the Snakedance Inn, in particular Mitch Daniels who worked sheer miracles. Given the success of the first Hot Quarks workshop we decided to organize a second one, possibly even turning Hot Quarks into a series. The next meeting will be held in the late spring of 2006, probably in Italy. We hope it will be as memorable as the first one! Last but not least, we wish to thank all the generous sponsors of the conference: Brookhaven National Laboratory, European Organization for Nuclear Research (CERN), Gesellschaft fA~ 1/4 r Schwerionenforschung (GSI), Institute of Physics Publishing, Los Alamos National Laboratory, National Science Foundation, and Vanderbilt University. We are grateful for their support and are particularly happy that this support came from institutions both in the US and in Europe and from all the main experimental facilities that pursue a prominent heavy-ion program. Their support was essential for the success of a workshop targeting young scientists.

Antinori, Federico; Bass, Steffen A.; Bellwied, Rene; Ullrich, Thomas; Velkovska, Julia; Wiedemann, Urs

2005-04-01

108

Polarized electronic absorption spectra of Co2+ ions in the kieserite-type compounds CoSO4 · H2O and CoSeO4 · H2O  

NASA Astrophysics Data System (ADS)

Polarized electronic absorption spectra of the kieserite-type compounds CoSO4 · H2O and CoSeO4 · H2O have been obtained at room temperature (spectral range 35 000-5000 cm-1) and at liquid nitrogen temperature (visible spectral region), using microscope-spectrometric techniques. The spectra are interpreted and evaluated in terms of a tetragonal crystal field formalism for the d7 configuration, in regard to the pseudotetragonal elongation of the CoO4(H2O)2 octahedra, known from previous X-ray structure investigations, employing the tetragonal parameters Dq, Dt, and Ds, and the Racah parameters B and C. The observed and calculated energy levels are in good agreement for the following parameter sets: CoSO4 · H2O: Dq=826, Dt=40, Ds=350, B=856, C=3580 cm-1; CoSeO4· H2O: Dq=817, Dt=44, Ds=406, B=841, C=3490 cm-1; corresponding ‘cubic’ crystal field strengths Dqcub are 803 and 792 cm-1, respectively. The values of Dq(cub), Racah B and C are in the common range for Co2+ ions in (pseudo) octahedral fields of oxygen ligands, and their differences in CoSO4· H2O compared to CoSeO4 · H2O are consistent with somewhat different mean Co-O bond lengths and with a slightly higher covalent contribution to Co-O bonding in the selenate compound. The values found for the parameter Dt, which is directly correlated to the extent of tetragonal distortion, are much lower than expected from purely geometrical considerations, thus confirming a significantly higher position of H2O ligands in the spectrochemical series compared to oxygen ligands belonging to SO4 or SeO4 groups.

Wildner, M.

1996-12-01

109

Hot Talk, Cold Science  

NASA Astrophysics Data System (ADS)

One of the hottest topics in climate science is understanding and evaluating the impacts of possible global warming caused by anthropogenic emissions of greenhouse gases. In Hot Talk, Cold Science, S. Fred Singer does not accept global warming. Singer says in his preface, “The purpose of this book is to demonstrate that the evidence [for global warming] is neither settled, nor compelling, nor even convincing. On the contrary, scientists continue to discover new mechanisms for climate change and to put forth new theories to try to account for the fact that global temperature is not rising, even though greenhouse theory says it should”.

Oglesby, Robert J.

110

Hot suit oven repairs  

SciTech Connect

The Donner-Hanna Coke Plant of Buffalo, New York has four coke oven batteries, the oldest being put into operation in 1943. A description is given of a method of repair developed by the company to repair stack waste heat tunnels and coke oven walls using a firesuit that allowed a repairman to work inside these hot areas. The procedure for the repair of coke oven walls is discussed in detail. A high duty castable was found to simulate the qualities of coke oven silica brick. The repair technique is relatively low cost without the attendant loss of production entailed by other methods of oven repair. (CKK)

Kolvek, R.E.; Bronke, H.R.

1982-01-01

111

Hot cell examination table  

DOEpatents

A table for use in a hot cell or similar controlled environment for use in examining specimens. The table has a movable table top that can be moved relative to a table frame. A shaft is fixedly mounted to the frame for axial rotation. A shaft traveler having a plurality of tilted rollers biased against the shaft is connected to the table top such that rotation of the shaft causes the shaft traveler to roll along the shaft. An electromagnetic drive is connected to the shaft and the frame for controllably rotating the shaft.

Gaal, Peter S. (Monroeville, PA); Ebejer, Lino P. (Weston, MA); Kareis, James H. (Slickville, PA); Schlegel, Gary L. (McKeesport, PA)

1991-01-01

112

Solar hot air system  

SciTech Connect

This solar hot air system is designed to trap and hold heat radiation from the sun, so as to heat one's home and reduce fuel consumption. It consists primarily of a glass, a screen, a collector, and air chambers, the combination of which utilizes two sheets of aluminum to trap and hold heat waves, until removed from the unit. It further includes a powerful small fan, to extract maximum heat from the collector while the sun is shining, and the unit is such, that it may be installed upon a vertical exterior wall, on a sloping roof, or upon a flat roof.

Moore, D.E.; Wiggins, J.W.

1983-04-12

113

Hot air drum evaporator  

DOEpatents

An evaporation system for aqueous radioactive waste uses standard 30 and 55 gallon drums. Waste solutions form cascading water sprays as they pass over a number of trays arranged in a vertical stack within a drum. Hot dry air is circulated radially of the drum through the water sprays thereby removing water vapor. The system is encased in concrete to prevent exposure to radioactivity. The use of standard 30 and 55 gallon drums permits an inexpensive compact modular design that is readily disposable, thus eliminating maintenance and radiation build-up problems encountered with conventional evaporation systems.

Black, Roger L. (Idaho Falls, ID)

1981-01-01

114

The Hot Tub Mystery  

NSDL National Science Digital Library

Roma and Clint Underhill are relaxing after a stressful day in their hot tub with some wine. But tragedy strikes, and the next morning their lifeless bodies are found in the water by their housekeeper. The paramedics who respond to her frantic 911 call pronounce the couple dead at the scene and call in the police to investigate. Developed for use in a lower-level undergraduate course on human physiology, students work through the various parts of this interrupted case to discover the cause of death, and in the process learn about blood pressure regulation.

House, Herbert

2005-01-01

115

Hot Off the Press  

NSDL National Science Digital Library

Environmental Health Perspectives (EHP) , a peer-reviewed environmental health research journal (published by the National Institute of Environmental Health Sciences, part of the National Institutes of Health,) provides the EHP Student Edition for high school and college teachers and their students. Each edition contains news articles that summarize a wide variety of scientific information and original research, which are paired with complementary lessons that introduce students to hot-off-the-press science. This article presents ways to integrate EHP's online content in the classroom.

Schlegel, Barry; Tart, Kimberly T.; Hemminger, Laura; Pitman, Lisa; Hines, Stefani; Stephan, Wendy

2006-10-01

116

Hot and Cold  

NSDL National Science Digital Library

In this activity, learners explore temperature changes from chemical reactions by mixing urea with water in one flask and mixing calcium chloride with water in another flask. They observe that the urea flask gets cold and the calcium chloride flask gets hot. The main idea is that some chemical processes release heat energy and are exothermic, while some chemical processes absorb heat energy and are endothermic. This activity is currently used in the Nature of Matter Unit in OMSI's Chemistry Lab. Cost estimates are per 100 learners.

Industry, Oregon M.

1997-01-01

117

Exploring Hot Neptune Atmospheres  

NASA Astrophysics Data System (ADS)

The first transiting 'hot Neptune'' GJ 436b inhabits an entirely new region of phase space for extrasolar planetary atmospheres. This relatively cool, low-mass object should be the first transiting extrasolar planet to sport a methane-rich atmosphere. Like Uranus and Neptune it may also have an atmosphere highly enriched in heavy elements. Our experience with the complex atmospheres of the known hot-Jupiters has demonstrated that insights are best gained through the combination of Spitzer observations and atmospheric modeling . However, no models have investigated the atmospheres of Neptune-class exoplanets, which may well be super metal-enriched, and span a wider range in stellar insolation and atmospheric composition than we have previously encountered. GJ 436b the coldest transiting planet, is in entirely new irradiation and mass regimes and is also the target of a barrage of planned Spitzer observations. Here we propose a new generation of atmospheric modeling to understand Spitzer observations of this new planet and others like it.

Fortney, Jonathan; Marley, Mark; Saumon, Didier

2008-03-01

118

Tuning the hot WD LF  

NASA Astrophysics Data System (ADS)

The recently presented [8] hot white dwarf (WD) luminosity function (LF) has been recalculated using a Monte Carlo method to obtain more realistic error estimates. New analysis of the SDSS hot standard WD completeness dependence on the SDSS g filter brightness and galactic latitude is shown and the results compared with a previously determined map of the hot standard completeness. A joined hot+cold LF is also presented as is the result of separation of the DA and non-DA LFs within -0.5 to 10 absolute bolometric magnitude range.

Krzesinski, Jurek

2010-11-01

119

The Hot-Wire and the Hot-Film Anemometers.  

National Technical Information Service (NTIS)

A survey is presented of hot-wire and hot-film anemometers for turbulent flow measurement, the dynamic response of the wire for the small overheat case is highlighted, as well as the constant temperature type of anemometer. A qualitative comparison is mad...

G. Comte-bellot

1975-01-01

120

Hot toys are dead: long live hot products  

Microsoft Academic Search

Recalls the hot toys phenomenon of several past Christmases in the USA, such as for Cabbage Patch dolls and Power Rangers. Argues that such toys created headlines in order to gain publicity, but also that this trend appears to have died because of eBay: what made toys hot and a cultural event was their inaccessibility, but eBay makes them all

Christopher Byrne

2005-01-01

121

Full of Hot Air: Hot Air Balloon Building  

NSDL National Science Digital Library

In this activity, learners create a model of a hot air balloon using tissue paper and a hairdryer. Educators can use this activity to introduce learners to density and its role in why things float. This activity page features a fun how-to video that shows learners and educators how to make the hot air balloons.

Houston, Children'S M.

2010-01-01

122

The Deep Hot Biosphere  

NASA Astrophysics Data System (ADS)

The first inhabitants of planet Earth were single-celled microorganisms and they are still with us today. Their name is truly legion, for they live everywhere, from boiling hot springs at the Earth's surface and on the seafloor to the coldest waters of the oceans and the Antarctic lakes. They are the masters of evolutionary adaptation, who have colonized the entire range of conditions under which water can exist as a liquid. At some ancient mythic time billions of years ago in a witches' brew of precursory molecules, somewhere, somehow, on a sunny Precambrian day bright with promise some of these molecules came together in the first coupling, learned to replicate, create enzymes, metabolize, and seal themselves into protective membranes inside of which they began the process of living. How they did this is our greatest mystery, for they are our primordial ancestors and we do not understand ourselves until we understand them.

Craig, Harmon

123

TRUEX hot demonstration  

SciTech Connect

In FY 1987, a program was initiated to demonstrate technology for recovering transuranic (TRU) elements from defense wastes. This hot demonstration was to be carried out with solution from the dissolution of irradiated fuels. This recovery would be accomplished with both PUREX and TRUEX solvent extraction processes. Work planned for this program included preparation of a shielded-cell facility for the receipt and storage of spent fuel from commercial power reactors, dissolution of this fuel, operation of a PUREX process to produce specific feeds for the TRUEX process, operation of a TRUEX process to remove residual actinide elements from PUREX process raffinates, and processing and disposal of waste and product streams. This report documents the work completed in planning and starting up this program. It is meant to serve as a guide for anyone planning similar demonstrations of TRUEX or other solvent extraction processing in a shielded-cell facility.

Chamberlain, D.B.; Leonard, R.A.; Hoh, J.C.; Gay, E.C.; Kalina, D.G.; Vandegrift, G.F.

1990-04-01

124

Response of hot nuclei  

SciTech Connect

The dipole giant resonance is reviewed, as it is the only vibration which has been experimentally identified in the decay of hot nuclei. The mechanism of exciting the resonance and the mode of the resonance are described. The methods used to calculate the vibrations from the shell model are discussed, including the Hartree-Fock approximation and random phase approximation. Nuclei formed by compound nuclear reactions, which possess high excitation energy and angular momentum, are considered. It is argued that the stability of the dipole may be used to advantage in the study of other properties of nuclei at high excitation. It is also considered possible that the discussion of the dipole giant resonance may be extended to the gamma decay of the isovector quadrupole vibration. 26 refs., 18 figs. (LEW)

Broglia, R.A.

1986-01-01

125

Electrical hot working safety program  

Microsoft Academic Search

An internal review of the safety practices for a large Canadian chemical plant indicated that the established procedures for electrical hot work needed to be expanded and formalized. Here, the authors describe how the practices were expanded into a comprehensive electrical hot work program that included a philosophy, controls, qualifications, and safe work methods. The program resulted in changes that

J. M. Gallagher; B. McClung

1996-01-01

126

Bae Wharton Hot Gas Laboratory.  

National Technical Information Service (NTIS)

A hot gas laboratory was built for experiments requiring large quantities of high pressure air (hot or cold), and was sited to allow test work of a very noisy nature. A ground erosion rig was constructed and commissioned in the laboratory to evaluate the ...

A. P. Winstanley

1985-01-01

127

Wood burning hot water heater  

Microsoft Academic Search

A heating device for supplying hot water to home heating systems and hot water faucet outlets in the home includes a combustion chamber which is adapted to burn wood fuel for supplying the necessary heat. The heating device comprises a base member containing an ash bin and ash door for the removal of burnt fuel, a water tank positioned on

1982-01-01

128

Hospital service hot water heating  

Microsoft Academic Search

This paper explores some of the design criteria and alternate solutions that an engineer might want to consider when designing a service hot water system for a hospital. Guidelines give the following estimated service hot water requirements for a hospital. Gallon per hr. per bed: clinical, 3; dietary, 2; laundry, 2. In addition, the guidelines state that these quantities of

Critschke

1985-01-01

129

Solar powered hot air balloon  

Microsoft Academic Search

A solar powered hot air balloon is disclosed having an envelope with an opaque portion and a transparent portion arranged so as to utilize solar heating to heat air within the envelope. The solar heating air may either be sufficient to provide the entire free lift or may be combined with air from a hot air generating system carried by

Eshoo

1979-01-01

130

Mammoth Hot Springs Online Tour  

NSDL National Science Digital Library

This Yellowstone National Park website offers an online tour of the Mammoth Hot Springs. Prominent hot springs and terraces are highlighted with photos and information concerning their cycles of activity. Similar tours of the Old Faithful area, the Norris Geyser Basin, the Fountain Paint Pots, and the Grand Canyon of Yellowstone are also available online.

Park, Yellowstone N.

131

Hot hollow cathode gun assembly  

DOEpatents

A hot hollow cathode deposition gun assembly includes a hollow body having a cylindrical outer surface and an end plate for holding an adjustable heat sink, the hot hollow cathode gun, two magnets for steering the plasma from the gun into a crucible on the heat sink, and a shutter for selectively covering and uncovering the crucible.

Zeren, J.D.

1983-11-22

132

Climate change hot-spots  

NASA Astrophysics Data System (ADS)

A Regional Climate Change Index (RCCI), is developed based on regional mean precipitation change, mean surface air temperature change, and change in precipitation and temperature interannual variability. The RCCI is a comparative index designed to identify the most responsive regions to climate change, or Hot-Spots. The RCCI is calculated for 26 land regions from the latest set of climate change projections by 20 global climate models for the A1B, A2 and B1 IPCC emission scenarios. The Mediterranean and North Eastern European regions emerge as the primary Hot-Spots, followed by high latitude northern hemisphere regions and by Central America, the most prominent tropical Hot-Spot. The main African Hot-Spots are Southern Equatorial Africa and the Sahara. Eastern North America is the prominent Hot-Spot over the continental U.S. Different factors over different regions contribute to the magnitude of the RCCI, which is in fact greater than 0 for all regions.

Giorgi, F.

2006-04-01

133

The Isvr Constant Temperature Hot Wire Anemometer.  

National Technical Information Service (NTIS)

The principles of hot wire anemometer operation are summarized. The design, specifications, and applications for the constant temperature hot wire and hot film anemometer system are discussed. Information is provided on probe construction with selected re...

P. O. A. L. Davies J. Mason

1974-01-01

134

Keep It Cool in Hot Weather  

MedlinePLUS

... in the Summer Sun Keep it Cool in Hot Weather Keep it Cool in Hot Weather Advice for Older People Applies to All ... factors that can increase risk include an extremely hot home, lack of transportation, overdressing and visiting overcrowded ...

135

Hot phonon dynamics in graphene.  

PubMed

The dynamics of hot phonons in supported, suspended, and gated monolayer graphene was studied by using time-resolved anti-Stokes Raman spectroscopy. We found that the hot phonon relaxation is dominated by phonon-phonon interaction in graphene, and strongly affected by the interaction between graphene and the substrate. Relaxation via carrier-phonon coupling, known as Landau damping, is ineffective for hot phonons which are in thermal equilibrium with excited carriers. Our findings provide a basis for better management of energy dissipation in graphene devices. PMID:23106146

Wu, Shiwei; Liu, Wei-Tao; Liang, Xiaogan; Schuck, P James; Wang, Feng; Shen, Y Ron; Salmeron, Miquel

2012-11-01

136

Hot dry rock reservoir engineering  

SciTech Connect

The Hot Dry Rock (HDR) concept is a simple one. Two nearly parallel wells are drilled, and hydraulic fractures are then formed to hydraulically connect the wells. Water pumped down the injection well and through the fracture system is heated by contact with the hot rock and rises to the production well. This hot fluid is passed through a heat exchanger at the surface and the extracted heat is used for direct heating or electricity generation. The cooled production fluid is then reinjected, thereby setting up a circulation loop. This paper describes the development and execution of the HDR project at Fenton Hill, New Mexico.

Murphy, H.

1987-01-01

137

Really Hot Stars  

NASA Astrophysics Data System (ADS)

Spectacular VLT Photos Unveil Mysterious Nebulae Summary Quite a few of the most beautiful objects in the Universe are still shrouded in mystery. Even though most of the nebulae of gas and dust in our vicinity are now rather well understood, there are some which continue to puzzle astronomers. This is the case of a small number of unusual nebulae that appear to be the subject of strong heating - in astronomical terminology, they present an amazingly "high degree of excitation". This is because they contain significant amounts of ions, i.e., atoms that have lost one or more of their electrons. Depending on the atoms involved and the number of electrons lost, this process bears witness to the strength of the radiation or to the impact of energetic particles. But what are the sources of that excitation? Could it be energetic stars or perhaps some kind of exotic objects inside these nebulae? How do these peculiar objects fit into the current picture of universal evolution? New observations of a number of such unusual nebulae have recently been obtained with the Very Large Telescope (VLT) at the ESO Paranal Observatory (Chile). In a dedicated search for the origin of their individual characteristics, a team of astronomers - mostly from the Institute of Astrophysics & Geophysics in Liège (Belgium) [1] - have secured the first detailed, highly revealing images of four highly ionized nebulae in the Magellanic Clouds, two small satellite galaxies of our home galaxy, the Milky Way, only a few hundred thousand light-years away. In three nebulae, they succeeded in identifying the sources of energetic radiation and to eludicate their exceptional properties: some of the hottest, most massive stars ever seen, some of which are double. With masses of more than 20 times that of the Sun and surface temperatures above 90 000 degrees, these stars are truly extreme. PR Photo 09a/03: Nebula around the hot star AB7 in the SMC. PR Photo 09b/03: Nebula near the hot Wolf-Rayet star BAT99-2 in the LMC. PR Photo 09c/03: Nebula near the hot binary star BAT99-49 in the LMC. PR Photo 09d/03: The N44C Nebula in the LMC. Four unique images of highly excited nebulae in the Magellanic Clouds ESO PR Photo 09a/03 ESO PR Photo 09a/03 [Preview - JPEG: 400 x 472 pix - 74k [Normal - JPEG: 800 x 943 pix - 720k] [Full-Res - JPEG: 1200 x 1414 pix - 1.2M] ESO PR Photo 09b/03 ESO PR Photo 09b/03 [Preview - JPEG: 400 x 466 pix - 70k [Normal - JPEG: 800 x 931 pix - 928k] [Full-Res - JPEG: 1200 x 1397 pix - 1.8M] ESO PR Photo 09c/03 ESO PR Photo 09c/03 [Preview - JPEG: 400 x 469 pix - 74k [Normal - JPEG: 800 x 937 pix - 1.1M] [Full-Res - JPEG: 1200 x 1405 pix - 2.2M] ESO PR Photo 09d/03 ESO PR Photo 09d/03 [Preview - JPEG: 400 x 473 pix - 28k [Normal - JPEG: 800 x 945 pix - 368k] [Full-Res - JPEG: 1200 x 1418 pix - 600k] Captions: PR Photo 09a/03 is a reproduction of a "near-true" three-colour composite image of the highly excited nebula around the hot double star AB7 in the Small Magellanic Cloud (SMC), obtained in January 2002 with the FORS1 multi-mode instrument at the 8.2-m VLT MELIPAL telescope at the Paranal Observatory (Chile). It is based on three exposures through narrow-band optical (interference) filters that isolate the light from specific atoms and ions. In this rendering, the blue colour represents the light from singly ionized Helium (He II; wavelength 468.6 nm; exposure time 30 min), green corresponds to doubly ionized oxygen ([O III]; 495.7 + 500.7 nm; 5 min) and red to hydrogen atoms (H; H-alpha line at 656.2 nm; 5 min). Of these three ions, He II is the tracer of high excitation, i.e. the bluest areas of the nebula are the hottest. The sky field measures 400 x 400 arcsec2; the original pixel size on the 2k x 2k CCD is 0.23 arcsec. North is up and east to the left. Before combination, the CCD frames were flat-fielded and cleaned of cosmic-rays. Moreover, the stars in the blue (He II) image were removed in order to provide a clearer view of the surrounding nebular emission. The reproduced brightness is proportional to the squar

2003-04-01

138

Hot Hydrogen Test Facility  

NASA Astrophysics Data System (ADS)

The core in a nuclear thermal rocket will operate at high temperatures and in hydrogen. One of the important parameters in evaluating the performance of a nuclear thermal rocket is specific impulse, ISP. This quantity is proportional to the square root of the propellant's absolute temperature and inversely proportional to square root of its molecular weight. Therefore, high temperature hydrogen is a favored propellant of nuclear thermal rocket designers. Previous work has shown that one of the life-limiting phenomena for thermal rocket nuclear cores is mass loss of fuel to flowing hydrogen at high temperatures. The hot hydrogen test facility located at the Idaho National Lab (INL) is designed to test suitability of different core materials in 2500°C hydrogen flowing at 1500 liters per minute. The facility is intended to test low activity uranium containing materials but is also suited for testing cladding and coating materials. In this first installment the facility is described. Automated data acquisition, flow and temperature control, vessel compatibility with various core geometries and overall capabilities are discussed.

Swank, W. David; Carmack, Jon; Werner, James E.; Pink, Robert J.; Haggard, Delon C.; Johnson, Ryan

2007-01-01

139

Do scientists trace hot topics?  

NASA Astrophysics Data System (ADS)

Do scientists follow hot topics in their scientific investigations? In this paper, by performing analysis to papers published in the American Physical Society (APS) Physical Review journals, it is found that papers are more likely to be attracted by hot fields, where the hotness of a field is measured by the number of papers belonging to the field. This indicates that scientists generally do follow hot topics. However, there are qualitative differences among scientists from various countries, among research works regarding different number of authors, different number of affiliations and different number of references. These observations could be valuable for policy makers when deciding research funding and also for individual researchers when searching for scientific projects.

Wei, Tian; Li, Menghui; Wu, Chensheng; Yan, Xiao-Yong; Fan, Ying; di, Zengru; Wu, Jinshan

2013-07-01

140

Dance of the hot dogs  

NASA Astrophysics Data System (ADS)

When two hot dogs are cooked in water, they undergo simultaneous 180° rotation about their long axis. Why do they turn? Why do they change orientation several times? Why do they do it at the same time?

Dindorf, Wojciech

2001-09-01

141

Hot embossing of microfluidic platform  

Microsoft Academic Search

Microfabrications of polymer are becoming increasingly important and considered as a low-cost alternative to the silicon or glass-based MEMS technologies. However, most of hot embossing studies were done on a thin film that may not fulfill the structure requirement of the product. In this study, micromolding via hot embossing was applied to microfeatured fluidic platform. The microfeature in the Ni–Co-based

Rean-Der Chien

2006-01-01

142

Large-scale hot embossing  

Microsoft Academic Search

The hot embossing process is a flexible molding technique to produce delicate microstructures with high aspect ratios on thin\\u000a layers. Large-scale hot embossing is one effective way to meet future requirements and produce high-quality microstructures\\u000a at low costs. For this, however, principal changes of the molding process and molding tool design will be required. In the\\u000a present paper, constructive solutions

M. Worgull; M. Heckele; W. K. Schomburg

2005-01-01

143

Performance of solar energy hot water systems  

NASA Astrophysics Data System (ADS)

A comparative analysis of solar energy hot water systems installed in sites monitored by the National Solar Data Network is presented. Two single family and two multi-family residences were selected for evaluation. These systems represent different types of hot water systems: passive hot water, active hot water with space heating, hot water with recirculation, and hot water thermosiphon. The data is provided in a number of forms including average monthly performance values for each hot water system, average monthly values for the summer and winter seasons, and estimated operational dollar savings. The conclusions are directed at both solar and conventional design features that cause good or bad performance.

Cramer, M. A.; Evans, K. D.; Rosenbusch, J. M.; Weinstein, R. A.

144

Hot Dry Rock - Summary  

SciTech Connect

Hot Dry Rock adds a new flexibility to the utilization of geothermal energy. Almost always the approach has been to limit that utilization to places where there is a natural source of water associated with a source of heat. Actually, the result was that steam was mined. Clearly there are much larger heat resources available which lack natural water to transport that energy to the surface. Also, as is found in hydrothermal fields being mined for steam, the water supply finally gets used up. There is a strong motive in the existing capital investment to revitalize those resources. Techniques for introducing, recovering and utilizing the water necessary to recover the heat from below the surface of the earth is the subject of this session. Implicit in that utilization is the ability to forecast with reasonable accuracy the busbar cost of that energy to the utility industry. The added element of supplying the water introduces costs which must be recovered while still supplying energy which is competitive. Hot Dry Rock technology can supply energy. That has been proved long since. The basic barrier to its use by the utility industry has been and remains proof to the financial interests that the long term cost is competitive enough to warrant investment in a technology that is new to utility on-grid operations. As the opening speaker for this session states, the test that is underway will ''simulate the operations of a commercial facility in some ways, but it will not show that energy from HDR can be produced at a variety of locations with different geological settings''. Further, the Fenton Hill system is a research facility not designed for commercial production purposes, but it can give indications of how the system must be changed to provide economic HDR operations. And so it is that we must look beyond the long term flow test, at the opportunities and challenges. Proving that the huge HDR resources can be accessed on a worldwide scale must involve the construction of additional sites, preferably to the specifications of the now Federal geothermal community. These facilities will have to be engineered to produce and market energy at competitive prices. At the same time, we must not rest on our technological laurels, though they be many. Design and operational techniques have been conceived which could lead to improved economics and operations for HDR. These must be pursued and where merit is found, vigorously pursued. Accelerated research and development ought to include revolutionary drilling techniques, reservoir interrogation, and system modeling to assure the competitiveness and geographical diversity of applications of HDR. Much of this work will be applicable to the geothermal industry in general. More advanced research ought to include such innovations as the utilization of other operating fluids. Supercritical carbon dioxide and the ammonia/water (Kalina) cycle have been mentioned. But even as the near and more distant outlook is examined, today's work was reported in the HDR session. The start-up operations for the current test series at the Fenton Hill HDR Pilot Plant were described. The surface plant is complete and initial operations have begun. While some minor modifications to the system have been required, nothing of consequence has been found to impede operations. Reliability, together with the flexibility and control required for a research system were shown in the system design, and demonstrated by the preliminary results of the plant operations and equipment performance. Fundamental to the overall success of the HDR energy resource utilization is the ability to optimize the pressure/flow impedance/time relationships as the reservoir is worked. Significant new insights are still being developed out of the data which will substantially affect the operational techniques applied to new systems. However, again, these will have to be proved to be general and not solely specific to the Fenton Hill site. Nevertheless, high efficiency use of the reservoir without unintended reservoir growth or water retention or

Tennyson, George P. Jr.

1992-03-24

145

Hot electron spectroscopy and microscopy  

NASA Astrophysics Data System (ADS)

Semiconductor heterostructures, such as double-barrier resonant tunnelling diodes and superlattices, are nowadays used for many applications. One very versatile and powerful method to study electronic transport in heterostructures is hot electron spectroscopy. Hot electron spectroscopy can be carried out in two complementary versions: device-based techniques usually employ so-called hot electron transistors (HETs), while ballistic electron emission microscopy (BEEM) uses a scanning tunnelling microscope (STM) as the source of ballistic electrons. In this review, spectroscopic results obtained by these two methods are compared and discussed. It is shown that BEEM results are strongly influenced by electron refraction effects, while the behaviour of HET devices is dominated by inelastic scattering effects in the base and drift region of the device. Thus, STM-based BEEM/S and HET-based spectroscopy are genuinely complementary methods, which yield supplementary results.

Smoliner, J.; Rakoczy, D.; Kast, M.

2004-10-01

146

Promethus Hot Leg Piping Concept  

SciTech Connect

The Naval Reactors Prime Contractor Team (NRPCT) recommended the development of a gas cooled reactor directly coupled to a Brayton energy conversion system as the Space Nuclear Power Plant (SNPP) for NASA's Project Prometheus. The section of piping between the reactor outlet and turbine inlet, designated as the hot leg piping, required unique design features to allow the use of a nickel superalloy rather than a refractory metal as the pressure boundary. The NRPCT evaluated a variety of hot leg piping concepts for performance relative to SNPP system parameters, manufacturability, material considerations, and comparison to past high temperature gas reactor (HTGR) practice. Manufacturability challenges and the impact of pressure drop and turbine entrance temperature reduction on cycle efficiency were discriminators between the piping concepts. This paper summarizes the NRPCT hot leg piping evaluation, presents the concept recommended, and summarizes developmental issues for the recommended concept.

AM Girbik; PA Dilorenzo

2006-01-24

147

Prometheus Hot Leg Piping Concept  

NASA Astrophysics Data System (ADS)

The Naval Reactors Prime Contractor Team (NRPCT) recommended the development of a gas cooled reactor directly coupled to a Brayton energy conversion system as the Space Nuclear Power Plant (SNPP) for NASA's Project Prometheus. The section of piping between the reactor outlet and turbine inlet, designated as the hot leg piping, required unique design features to allow the use of a nickel superalloy rather than a refractory metal as the pressure boundary. The NRPCT evaluated a variety of hot leg piping concepts for performance relative to SNPP system parameters, manufacturability, material considerations, and comparison to past high temperature gas reactor (HTGR) practice. Manufacturability challenges and the impact of pressure drop and turbine entrance temperature reduction on cycle efficiency were discriminators between the piping concepts. This paper summarizes the NRPCT hot leg piping evaluation, presents the concept recommended, and summarizes developmental issues for the recommended concept.

Gribik, Anastasia M.; Dilorenzo, Peter A.

2007-01-01

148

Archaeal Nitrification in Hot Springs  

NASA Astrophysics Data System (ADS)

Biological nitrification, i.e. the aerobic conversion of ammonia to nitrate via nitrite, is a major component of the global nitrogen cycle. Until recently, it was thought that the ability to aerobically oxidize ammonia was confined to bacteria of the phylum Proteobacteria. However, it has recently been shown that Archaea of the phylum Crenarchaeota are also capable of ammonia oxidation. As many Crenarchaeota are thermophilic or hyperthermophilic, and at least some of them are capable of ammonia oxidation we speculated on the existence of (hyper)thermophilic ammonia-oxidizing archaea (AOA). Using PCR primers specifically targeting the archaeal ammonia monooxygenase (amoA) gene, we were indeed able to confirm the presence of such organisms in several hot springs in Reykjadalur, Iceland. These hot springs exhibited temperatures well above 80 °C and pH values ranging from 2.0 to 4.5. To proof that nitrification actually took place under these extreme conditions, we measured gross nitrification rates by the isotope pool dilution method; we added 15N-labelled nitrate to the mud and followed the dilution of the label by nitrate production from ammonium either in situ (incubation in the hot spring) or under controlled conditions in the laboratory (at 80 °C). The nitrification rates in the hot springs ranged from 0.79 to 2.22 mg nitrate-N per L of mud and day. Controls, in which microorganisms were killed before the incubations, demonstrated that the nitrification was of biological origin. Addition of ammonium increased the gross nitrification rate approximately 3-fold, indicating that the nitrification was ammonium limited under the conditions used. Collectively, our study provides evidence that (1) AOA are present in hot springs and (2) that they are actively nitrifying. These findings have major implications for our understanding of nitrogen cycling of hot environments.

Richter, A.; Daims, H.; Reigstad, L.; Wanek, W.; Wagner, M.; Schleper, C.

2006-12-01

149

Hot Lingo 2.0  

NSDL National Science Digital Library

This handy little application offers form and applet spell checking for Internet Explorer 5.0 and higher, something that will be useful for persons looking to perform spell-checking in a number of settings and applications. Hot Lingo utilizes a 75,000 word English dictionary, and with this version, users can create a customizable dictionary that contains up to 32,000 additional words. Their Web site also contains a FAQ section, and a place where users can offer feedback on the functionality of the application. Hot Lingo is compatible with all of the Windows operating systems.

2000-01-01

150

Hot, Cold, and Really Cold.  

ERIC Educational Resources Information Center

|Describes a physics experiment investigating temperature prediction and the relationship between the physical properties of heat units, melting, dissolving, states of matter, and energy loss. Details the experimental setup, which requires hot and cold water, a thermometer, and ice. Notes that the experiment employs a deliberate counter-intuitive…

Leyden, Michael

1997-01-01

151

Enviropower hot gas desulfurization pilot  

Microsoft Academic Search

The objectives of the project are to develop and demonstrate (1) hydrogen sulfide removal using regenerable zinc titanate sorbent in pressurized fluidized bed reactors, (2) recovery of the elemental sulfur from the tail-gas of the sorbent regenerator and (3) hot gas particulate removal system using ceramic candle filters. Results are presented on pilot plant design and testing and modeling efforts.

R. Ghazanfari; G. Feher; J. Konttinen; A. Lehtovaara; W. Mojtahedi

1994-01-01

152

Production of hot-wires  

NASA Astrophysics Data System (ADS)

Several methods for producing hot-wire probes are described. Discussion includes the manufacture of probe bodies, soldering plated wires to the prongs etching Walaston type wires, and finishing the probe. This report is written as an instruction manual for researchers who desire to produce or repair their own sensors.

Dickinson, S. C.

1983-04-01

153

Constitutive analysis in hot working  

Microsoft Academic Search

Constitutive equations including an Arrhenius term have been commonly applied to steels with the objective of calculating hot rolling and forging forces. The function relating stress and strain rate is generally the hyperbolic-sine since the power and exponential laws lose linearity at high and low stresses, respectively. In austenitic steels, the equations have been used primarily for the peak stress

H. J McQueen; N. D Ryan

2002-01-01

154

Hot Springs: Valley of Vapors.  

National Technical Information Service (NTIS)

Best known for its 47 mineral-rich hot springs by those seeking relief in the ancient tradition of thermal bathing, This Arkansas mecca has been visited first by Indians seeking mudholes and later by turn-of-the century visitors coming to enjoy the plush ...

1994-01-01

155

Solar Technician Program Blows Hot  

ERIC Educational Resources Information Center

|A training program for solar heating technicians was initiated at Sonoma State College's School of Environmental Studies for CETA applicants. Among the projects designed and built were a solar alternative energy center, a solar hot water system, and a solar greenhouse. (MF)|

Ziegler, Peg Moran

1977-01-01

156

Hot Isostatic Pressing of Ceramics.  

National Technical Information Service (NTIS)

A mixture containing glass 70 to 95 and BN or B4C powder (0.1-10 microns) 5 to 30 vol. % is used as a secondary pressure medium in hot isostatic pressing of ceramics. Thus, Pyrex beads were mixed with 15% vol. BN powder (average diameter 2 microns), fused...

K. Honma

1985-01-01

157

Tribology of hot metal forming  

Microsoft Academic Search

Many aspects of the tribology of hot metal forming are poorly understood. This leads to difficulties when modelling the forming operations to develop process improvements. It also handicaps the development of new tool materials, since the operating conditions with which they will have to cope are not fully described. Several key issues in friction, heat transfer, lubrication, wear and fatigue

J. H Beynon

1998-01-01

158

Flying hot-wire anemometry  

Microsoft Academic Search

A flying hot-wire arrangement has been developed for the measurement of the velocity characteristics of the flow around airfoils, and particularly in regions where negative values of instantaneous velocity occur. The mechanism and signal processing system are described and appraised by comparing stationary and flying wire measurements obtained in the trailing edge region of a flap at an angle of

B. E. Thompson; J. H. Whitelaw

1984-01-01

159

Upside's Hot 100 Awards: 1999  

NSDL National Science Digital Library

The business technology magazine Upside Today authors this list of the "hottest private high-tech companies of 1999." Upside editors considered entrepreneurial passion as well as the "staying power" of companies to be top criteria for the Hot 100 Awards. Each listing includes a company profile with homepage links where available.

160

Hot Issues at Community Colleges  

NSDL National Science Digital Library

The issues listed on this website are a reflection of AACC's strategic action areas. Their intent is to provide users with a cross-section of important issues surrounding community colleges. These issues will change as the scope and intensity of these issues change. Browse through the list of "hot issues" affecting community colleges today.

2010-06-09

161

Detection of Hot Halo Gets Theory Out of Hot Water  

NASA Astrophysics Data System (ADS)

Scientists using NASA's Chandra X-ray Observatory have detected an extensive halo of hot gas around a quiescent spiral galaxy. This discovery is evidence that galaxies like our Milky Way are still accumulating matter from the gradual inflow of intergalactic gas. "What we are likely witnessing here is the ongoing galaxy formation process," said Kristian Pedersen of the University of Copenhagen, Denmark, and lead author of a report on the discovery. Chandra observations show that the hot halo extends more than 60,000 light years on either side of the disk of the galaxy known as NGC 5746. The detection of such a large halo alleviates a long-standing problem for the theory of galaxy formation. Spiral galaxies are thought to form from enormous clouds of intergalactic gas that collapse to form giant, spinning disks of stars and gas. Chandra X-ray Image of NGC 5746 Chandra X-ray Image of NGC 5746 One prediction of this theory is that large spiral galaxies should be immersed in halos of hot gas left over from the galaxy formation process. Hot gas has been detected around spiral galaxies in which vigorous star formation is ejecting matter from the galaxy, but until now hot halos due to infall of intergalactic matter have not been detected. "Our observations solve the mystery of the missing hot halos around spiral galaxies," said Pedersen. "The halos exist, but are so faint that an extremely sensitive telescope such as Chandra is needed to detect them." DSS Optical Image of NGC 5746 DSS Optical Image of NGC 5746 NGC 5746 is a massive spiral galaxy about a 100 million light years from Earth. Its disk of stars and gas is viewed almost edge-on. The galaxy shows no signs of unusual star formation, or energetic activity from its nuclear region, making it unlikely that the hot halo is produced by gas flowing out of the galaxy. "We targeted NGC 5746 because we thought its distance and orientation would give us the best chance to detect a hot halo caused by the infall of intergalactic gas," said Jesper Rasmussen of the University of Birmingham, United Kingdom and a coauthor of the report. "What we found is in good agreement with computer simulations in which galaxies are built up gradually from the merger of smaller clouds of hot gas and dark matter." The computer simulations were done by Jesper Sommer-Larsen (also a coauthor of the report) and collaborators at the University of Copenhagen. The paper describing these results will be published in the April issue of the journal New Astronomy. Other researchers on this project were Sune Toft, Yale University; Andrew Benson, University of Oxford, United Kingdom; and Richard Bower, University of Durham, United Kingdom. NASA's Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program for the agency's Science Mission Directorate. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center in Cambridge, Mass. http://chandra.harvard.edu and http://chandra.nasa.gov

2006-02-01

162

Enriching the hot circumgalactic medium  

NASA Astrophysics Data System (ADS)

Simple models of galaxy formation in a cold dark matter universe predict that massive galaxies are surrounded by a hot, quasi-hydrostatic circumgalactic corona of slowly cooling gas, predominantly accreted from the intergalactic medium (IGM). This prediction is borne out by the recent cosmological hydrodynamical simulations of Crain et al., which reproduce observed scaling relations between the X-ray and optical properties of nearby disc galaxies. Such coronae are metal poor, but observations of the X-ray emitting circumgalactic medium (CGM) of local galaxies typically indicate enrichment to near-solar iron abundance, potentially signalling a shortcoming in current models of galaxy formation. We show here that, while the hot CGM of galaxies formed in the simulations is typically metal poor in a mass-weighted sense, its X-ray luminosity-weighted metallicity is often close to solar. This bias arises because the soft X-ray emissivity of a typical ˜0.1 keV corona is dominated by collisionally excited metal ions that are synthesized in stars and recycled into the hot CGM. We find that these metals are ejected primarily by stars that form in situ to the main progenitor of the galaxy, rather than in satellites or external galaxies. The enrichment of the hot CGM therefore proceeds in an `inside-out' fashion throughout the assembly of the galaxy: metals are transported from the central galaxy by supernova-driven winds and convection over several Gyr, establishing a strong negative radial metallicity gradient. Whilst metal ions synthesized by stars are necessary to produce the X-ray emissivity that enables the hot CGM of isolated galaxies to be detected with current instrumentation, the electrons that collisionally excite them are equally important. Since our simulations indicate that the electron density of hot coronae is dominated by the metal-poor gas accreted from the IGM, we infer that the hot CGM observed via X-ray emission is the outcome of both hierarchical accretion and stellar recycling.

Crain, Robert A.; McCarthy, Ian G.; Schaye, Joop; Theuns, Tom; Frenk, Carlos S.

2013-07-01

163

Hot-Electron Direct Detector for Radioastronomy.  

National Technical Information Service (NTIS)

A hot-electron transition-edge superconducting bolometer with adjustable thermal relaxation speed is proposed. The bolometer contacts are made from a superconductor with high critical temperature which blocks the thermal diffusion of hot carriers into the...

B. S. Karasik W. R. McGrath H. G. LeDuc M. E. Gershenson

1999-01-01

164

Hot Particles: Risks, Regulations and ALARA.  

National Technical Information Service (NTIS)

In recent years, few areas of health physics have involved as many issues, problems and concerns as exposures of workers to hot particles. Current practices and responses to hot particle contaminations and exposure events have prompted many health physici...

S. E. Merwin M. P. Moeller

1989-01-01

165

16 CFR 1505.51 - Hot surfaces.  

Code of Federal Regulations, 2013 CFR

...Commercial Practices 2 2013-01-01 2013-01-01 false Hot surfaces. 1505.51 Section 1505.51 Commercial Practices...USE BY CHILDREN Policies and Interpretations § 1505.51 Hot surfaces. (a) Test probe. Section...

2013-01-01

166

Could Hot Cocoa Improve Brainpower in Seniors?  

MedlinePLUS

... features on this page, please enable JavaScript. Could Hot Cocoa Improve Brainpower in Seniors? Small early study ... A preliminary new study links two cups of hot cocoa per day to improved memory skills in ...

167

Fever, Sweats, and Hot Flashes (PDQ)  

MedlinePLUS

... Research & Funding News About NCI Fever, Sweats, and Hot Flashes (PDQ®) Patient Version Health Professional Version En ... Last Modified: 06/13/2013 Fever, Sweats, and Hot Flashes (PDQ®) Overview Causes of Fever in Patients ...

168

Assessment of hot gas contaminant control  

Microsoft Academic Search

The objective of this work is to gather data and information to assist DOE in responding to the NRC recommendation on hot gas cleanup by performing a comprehensive assessment of hot gas cleanup systems for advanced coal-based Integrated Gasification Combined Cycle (IGCC) and Pressurized Fluidized Bed Combustion (PFBC) including the status of development of the components of the hot gas

M. D. Rutkowski; M. G. Klett; R. Zaharchuk

1996-01-01

169

Hot Corrosion in a Temperature Gradient  

Microsoft Academic Search

Hot corrosion is the accelerated attack of materials at elevated temperatures that is induced by a thin film of fused salt. Many materials that experience hot corrosion are exposed to high heat fluxes and temperature gradients. The hot corrosion of metals can be described by the dissolution of a protective metal oxide into the fused salt and the subsequent precipitation

Gordon Holcomb

1999-01-01

170

Hot Corrosion in a Temperature Gradient  

Microsoft Academic Search

Hot corrosion is the accelerated attack of materials at elevated temperatures that is induced by a thin film of fused salt. Many materials that experience hot corrosion are exposed to high heat fluxes and temperature gradients. The hot corrosion of metals can be described by the dissolution of a protective metal oxide into the fused salt and the subsequent precipitation

G. R. Holcomb

2000-01-01

171

Hot Flame Cut Study. Volume III.  

National Technical Information Service (NTIS)

The hot shearing and hot flame cutting concepts of billet separation for use in projectile forging applications were investigated during this project. The hot parting concept of billet separation involves heating 20 to 24 foot lengths of billet stock to f...

D. O. Gustad

1977-01-01

172

Collision Density of Hot Atoms. II  

Microsoft Academic Search

Analytical and stochastic methods are used to investigate hot-atom reactions for relatively low-energy hot atoms such as those produced by photochemical processes. Collision densities for hot atoms are presented for several reactive systems in which the reaction probability and the threshold energy are varied. Solutions for the collision density obtained by analytical methods and independently by stochastic methods were in

D. M. Chapin; M. D. Kostin

1967-01-01

173

Corrosion of hot end automotive exhaust components  

Microsoft Academic Search

Purpose – To evaluate the corrosion resistance of four different stainless steels often employed in hot end exhaust components. Design\\/methodology\\/approach – This paper evaluated the outcomes of the hot salt test and the cyclic oxidation test on four different stainless steels, used as hot end exhaust components. The specimens were analyzed by means of SEM for surface changes and the

J. H. Potgieter; M. Sephton; Z. W. Nkosi

2007-01-01

174

Insights into good hot oiling practices.  

National Technical Information Service (NTIS)

One of the common oil-field wellbore problems is paraffin deposition. Even though hot oiling is usually the first method tried for removing paraffin, few operators appreciate the limitations of hot oiling and the potential for hot oiling to aggravate well...

A. J. Mansure K. M. Barker

1992-01-01

175

Effektiv brugsvandsopvarmning. (Efficient domestic hot water heating).  

National Technical Information Service (NTIS)

The aim was to investigate alternative, electrically or gas/oil heated, domestic hot water systems to find potentials for minimum heat loss from pipes and hot water tanks. Experiments were carried out on a 10 l electrically heated hot water heater and a 2...

J. M. Schultz

1991-01-01

176

Hot Pages: Software Caching for Raw Microprocessors  

Microsoft Academic Search

This paper describes Hot Pages, a software solution for managingon-chip data on the Raw Machine, a scalable, parallel, microprocessorarchitecture. This software system transparently managesthe mapping between the program address space and on-chipmemory. Hot Pages combines compile time information to selectivelyvirtualize memory references and to eliminate many cachetaglookups. For many of the memory accesses that cannot be fullypredicted, Hot Pages replaces

Csaba Andras Moritz; Matthew Frank; Walter Lee; Saman Amarasinghe

1999-01-01

177

Residential hot water use patterns in Greece  

Microsoft Academic Search

This paper presents the results from the monitoring of hot water consumption in four apartment buildings that are located in Solar Village 3, in Greece. The buildings were monitored centrally for hot water consumption using a Data Acquisition System (DAS). The hot water is prepared in one building by an air-to-water heat pump and in the other three buildings by

K. T. Papakostas; N. E. Papageorgiou; B. A. Sotiropoulos

1995-01-01

178

Corrosion protection for offshore hot risers  

Microsoft Academic Search

The prevention of external splashzone corrosion on hot risers has required application of special protection techniques. A number of improperly protected hot risers have suffered an unexpected high corrosion rate during initial operations in the North Sea. One incident led to a riser rupture, fire, and loss of lives. On a hot riser, heat fluxes and increased external steel surface

N. Nilsen; B. Espelid; R. K. Hansen

1983-01-01

179

Hot atom chemistry and radiopharmaceuticals  

SciTech Connect

The chemical products made in a cyclotron target are a combined result of the chemical effects of the nuclear transformation that made the radioactive atom and the bulk radiolysis in the target. This review uses some well-known examples to understand how hot atom chemistry explains the primary products from a nuclear reaction and then how radiation chemistry is exploited to set up the optimal product for radiosynthesis. It also addresses the chemical effects of nuclear decay. There are important principles that are common to hot atom chemistry and radiopharmaceutical chemistry. Both emphasize short-lived radionuclides and manipulation of high specific activity nuclides. Furthermore, they both rely on radiochromatographic separation for identification of no-carrieradded products.

Krohn, Kenneth A.; Moerlein, Stephen M.; Link, Jeanne M.; Welch, Michael J. [University of Washington, Department of Radiology, Molecular Imaging Center, 1959 NE Pacific St., Box 356004, Seattle, WA 98195-6004 (United States); Washington University, Department of Radiology, Division of Radiological Sciences, 510 South Kingshighway, St. Louis, MO 63110 (United States); University of Washington, Department of Radiology, Molecular Imaging Center, 1959 NE Pacific St., Box 356004, Seattle, WA 98195-6004 (United States); Washington University, Department of Radiology, Division of Radiological Sciences, 510 South Kingshighway, St. Louis, MO 63110 (United States)

2012-12-19

180

HOT HYDROGEN IN DIFFUSE CLOUDS  

SciTech Connect

Laboratory evidence suggests that recombination of adsorbed radicals may cause an abrupt temperature excursion of a dust grain to about 1000 K. One consequence of this is the rapid desorption of adsorbed H{sub 2} molecules with excitation temperatures of this magnitude. We compute the consequences of injection of hot H{sub 2} into cold diffuse interstellar gas at a rate of 1% of the canonical H{sub 2} formation rate. We find that the level populations of H{sub 2} in J = 3, 4, and 5 are close to observed values, and that the abundances of CH{sup +} and OH formed in reactions with hot hydrogen are close to the values obtained from observations of diffuse clouds.

Cecchi-Pestellini, Cesare [INAF-Osservatorio Astronomico di Cagliari, Strada n.54, Loc. Poggio dei Pini, I-09012 Capoterra (Italy); Duley, Walt W. [Department of Physics and Astronomy, University of Waterloo, Ontario N2L 3G1 (Canada); Williams, David A., E-mail: ccp@oa-cagliari.inaf.it, E-mail: wwduley@uwaterloo.ca, E-mail: daw@star.ucl.ac.uk [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom)

2012-08-20

181

Hot electron emission in semiconductors  

NASA Astrophysics Data System (ADS)

The hot electron emission from low and high mobility GaAs/GaAlAs heterostructures was investigated in the FIR range at two frequencies. From the analysis a linear dependence of the electron temperature on input power per electron is found, nearly independent of the sample properties. The interaction of drifting carriers with periodic gratings in high mobility GaAs/GaAlAs systems is a promising scheme to obtain microwatt tunable FIR radiation.

Gornik, E.; Hoepfel, R.; Helm, M.

1985-01-01

182

Hot and Cold Ideal Gases  

NSDL National Science Digital Library

The EJS Hot and Cold Ideal Gases model simulates the mixing of hot and cold two-dimensional ideal gases in a square box. This simulation can be used as part of the activity described in "The Statistical Interpretation of Entropy: An Activity" by Todd Timberlake, to be published in The Physics Teacher. In the model, one gas is initially confined to the left side of the box while the other gas is confined to the right side. An animation window shows the motion of the particles in the box, while an optional graph window plots the temperature of each side of the box, which is determined by measuring the average KE of the particles on each side. The initial number of particles and temperature on each side of the square can be changed and a button allows the user to reverse the particle velocities at any time. The user can modify this simulation if EJS is installed locally by right-clicking within the plot and selecting "Open Ejs Model" from the pop-up menu item. EJS Hot and Cold Ideal Gases model was created using the Easy Java Simulations (EJS) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the ejs_entropy_HotAndColdIdealGases.jar file will run the program if Java is installed. EJS is a part of the Open Source Physics Project and is designed to make it easier to access, modify, and generate computer models. Additional EJS models are available. They can be found by searching ComPADRE for Open Source Physics, OSP, or EJS.

Timberlake, Todd

2010-07-01

183

Hot gas engine heater head  

DOEpatents

A heater head for a multi-cylinder double acting hot gas engine in which each cylinder is surrounded by an annular regenerator unit, and in which the tops of each cylinder and its surrounding regenerator are interconnected by a multiplicity of heater tubes. A manifold for the heater tubes has a centrally disposed duct connected to the top of the cylinder and surrounded by a wider duct connecting the other ends of the heater tubes with the regenerator unit.

Berntell, John O. (Staffanstorp, SE)

1983-01-01

184

"Hotness" stability of chicken hot-wing products as affected by preparation methods and storage.  

PubMed

Chicken hot-drumettes containing 2% cayenne pepper were prepared using three different cooking methods and stored under two different temperatures for "hotness" evaluation. Results demonstrated that the hotness of the samples were highest when products were cooked in a microwave oven, followed by convection oven, and least hot by deep-fat frying. Regardless of the cooking method, the degree of hotness of the hot-drumette decreased drastically during refrigerated storage. Results also indicated that the loss of hotness was associated with the increase of 2-thiobarbituric acid (TBA) values in the product. The addition of antioxidants such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), rosemary, and sodium nitrate during preparation or vacuum packaging retarded lipid oxidation of chicken hot-drumettes and retarded the loss of hotness of the products during refrigerated storage. PMID:9565248

Chang, M H; Chen, T C

1998-04-01

185

Subjective and objective measures of hot flashes.  

PubMed

Up to 75% of women in the US report having experienced hot flashes during the menopausal transition. The purpose of this review is to describe the physiology of hot flashes, and the ways in which hot flashes have been examined by subjective report and by objective measurement. Hot flashes occur because of an activation of the heat dissipation response, possibly triggered by a hypothalamic mechanism within the context of declining estrogen levels. There is cross-population variation in the frequency of self-reported hot flashes, although cross-study comparisons are problematic because of incompatibilities in study design. Diaries are a good way to collect information on the time and severity of hot flashes, and body diagrams allow researchers to study the pattern of heat and sweating. Hot flashes can be objectively measured by increases in heart rate, finger blood flow, respiratory exchange ratio, skin temperature, and core body temperature. Sternal skin conductance is the method most highly correlated with subjective hot flash report. In a laboratory, concordance between subjective report and sternal skin conductance can approach 100%. Ambulatory monitoring allows for the tracking of hot flashes during a woman's daily routine or sleep; however, concordance is much lower with ambulatory, compared to laboratory, monitoring. The study of hot flashes at menopause provides a model for the study of any experience that can be assessed by both self-report and biometric measurement. Am. J. Hum. Biol., 25:573-580, 2013. © 2013 Wiley Periodicals, Inc. PMID:23897855

Sievert, Lynnette Leidy

2013-07-30

186

How Hot is That Star  

NSDL National Science Digital Library

This resource is part of the Science Education Gateway (SEGway) project, funded by NASA, which is a national consortium of scientists, museums, and educators working together to bring the latest science to students, teachers, and the general public. How hot is the Sun? How do scientists know? Students perform guided Web research through several sites on solar astronomy to answer theses questions, and more: how to measure the temperature of any star, and how astronomers use Hertzsprung-Russell (H-R) diagrams to classify stars by temperature and luminosity. This unit is divided into six lessons, and contains feedback from other educators who have used this module.

Meunier, Jim; Lehman, Jim

187

Hot moons and cool stars  

NASA Astrophysics Data System (ADS)

The exquisite photometric precision of the Kepler space telescope now puts the detection of extrasolar moons at the horizon. Here, we firstly review observational and analytical techniques that have recently been proposed to find exomoons. Secondly, we discuss the prospects of characterizing potentially habitable extrasolar satellites. With moons being much more numerous than planets in the solar system and with most exoplanets found in the stellar habitable zone being gas giants, habitable moons could be as abundant as habitable planets. However, satellites orbiting planets in the habitable zones of cool stars will encounter strong tidal heating and likely appear as hot moons.

Heller, René; Barnes, Rory

2013-04-01

188

Modeling Hot and Cold Planets  

NSDL National Science Digital Library

These are the student pages for a three part lesson plan in which students investigate a physical model representing a cold and a hot planet. In the second part, the students interact with a computer model that simulates extreme conditions on some planets, and in the third part they will utilize a data source from the internet to determine the average temperature of the earth and specify the characteristics of a sampling necessary to achieve an accurate average. The lesson plan includes an overview, learning objectives, a list of materials, procedure, data analysis, and worksheets. Teachers' notes are also included.

189

ADVANCED HOT GAS FILTER DEVELOPMENT  

SciTech Connect

Iron aluminide hot gas filters have been developed using powder metallurgy techniques to form seamless cylinders. Three alloys were short-term corrosion tested in simulated IGCC atmospheres with temperatures between 925 F and 1200 F with hydrogen sulfide concentrations ranging from 783 ppm{sub v} to 78,300 ppm{sub v}. Long-term testing was conducted for 1500 hours at 925 F with 78,300 ppm{sub v}. The FAS and FAL alloys were found to be corrosion resistant in the simulated environments. The FAS alloy has been commercialized.

Matthew R. June; John L. Hurley; Mark W. Johnson

1999-04-01

190

Hot tearing studies in AA5182  

NASA Astrophysics Data System (ADS)

One of the major problems during direct chill (DC) casting is hot tearing. These tears initiate during solidification of the alloy and may run through the entire ingot. To study the hot tearing mechanism, tensile tests were carried out in semisolid state and at low strain rates, and crack propagation was studied in situ by scanning electron microscopy (SEM). These experimentally induced cracks were compared with hot tears developed in an AA5182 ingot during a casting trial in an industrial research facility. Similarities in the microstructure of the tensile test specimens and the hot tears indicate that hot tearing can be simulated by performing tensile tests at semisolid temperatures. The experimental data were compared with existing hot tearing models and it was concluded that the latter are restricted to relatively high liquid fractions because they do not take into account the existence of solid bridges in the crack.

van Haaften, W. M.; Kool, W. H.; Katgerman, L.

2002-10-01

191

Hot Topic Detection in Professional Blogs  

Microsoft Academic Search

\\u000a Topics in professional blogs mainly refer to specific techniques. Today, professional blog websites have been important information\\u000a sources. However, information overload and the uncertainty of topic hotness evaluation have been obstacles for hot topic detection.\\u000a The paper proposes a method of detecting hot topics in professional blogs. The proposed method is based on the characteristics\\u000a of the professional blogs and

Erzhong Zhou; Ning Zhong; Yuefeng Li

192

The hollow-cathode hot filament arc  

Microsoft Academic Search

A discharge system with a hot filament mounted inside a cylindrical hollow cathode designed to produce a low-pressure arc discharge is described together with the discharge characteristics. The combination of a hot filament and a hollow cathode allows a decrease in discharge operating voltage and a 3-4-fold increase in discharge current as compared to a configuration containing only a hot

D. P. Borisov; N. N. Koval; P. M. Schanin

1996-01-01

193

Abundances in Hot Evolved Stars  

NASA Astrophysics Data System (ADS)

The hydrogen-deficiency in extremely hot post-AGB stars of spectral class PG1159 is probably caused by a (very) late helium-shell flash or a AGB final thermal pulse that consumes the hydrogen envelope, exposing the usually-hidden intershell region. Thus, the photospheric element abundances of these stars allow us to draw conclusions about details of nuclear burning and mixing processes in the precursor AGB stars. We compare predicted element abundances to those determined by quantitative spectral analyses performed with advanced non-LTE model atmospheres. A good qualitative and quantitative agreement is found for many species (He, C, N, O, Ne, F, Si, Ar) but discrepancies for others (P, S, Fe) point at shortcomings in stellar evolution models for AGB stars. Almost all of the chemical trace elements in these hot stars can only be identified in the UV spectral range. The Far Ultraviolet Spectroscopic Explorer and the Hubble Space Telescope played a crucial role for this research.

Werner, Klaus; Rauch, Thomas; Kruk, Jeffrey W.

2009-05-01

194

DOE hot dry rock program  

SciTech Connect

Hydraulic fracturing has been used to create and subsequently to enlarge the first hot dry rock heat-extraction loop at Fenton Hill, New Mexico. Encouraging results prompted the DOE to expand this project into a program of national scope. The elements of that Program and their present status are discussed. Emphasis is given the ongoing Fenton Hill Project where techniques and information developed in the existing research system will soon be used to produce a multiply-fractured engineering system in hotter rock at the same site. Recent results from research loop operation and progress in constructing the engineering system are reported. Although acoustic mapping and system geometry indicate that the primary hydraulic fractures are essentially vertical, relatively low fracturing pressure and absence of a sharp breakdown suggest that at Fenton Hill fracture initiation occurs by reopening of old natural fractures rather than by initiation of new ones. Flow patterns and temperature behavior suggest opening of additional old fractures as the loop is operated. Except where the hot fluid leaves the crack system to enter the production well, flow impedances are very low without either artificial propping or inflation by pressurization.

Nunz, G.J.

1980-01-01

195

Hot torsion tests to model the deformation behavior of aluminium alloys at hot working temperatures  

Microsoft Academic Search

Knowledge of the deformation behavior of aluminium alloys at hot working temperatures is very important for high temperature manufacturing processes such as hot extrusion. Hot torsion tests were adopted to model this property in this paper. Constitutive equations for stress and strain were developed based on the functional relationship between torque and twist, which enables the material constants to be

M Zhou; M. P Clode

1997-01-01

196

Valuation method for effects of hot stamping process parameters on product properties using hot forming simulator  

Microsoft Academic Search

Hot stamping is one of the hot forming processes for manufacturing products of lightweight construction such as lightweight vehicles. Knowledge on the characteristics of the hot stamping process is significant in designing and optimizing the process conditions, dies and tools; however, until now, the characteristics of this process, such as the relationships between a product property and die temperature and

Katsuyoshi Ikeuchi; Jun Yanagimoto

2011-01-01

197

Hot electron production and heating by hot electrons in fast ignitor research  

SciTech Connect

In an experimental study of the physics of fast ignition the characteristics of the hot electron source at laser intensities up to 10(to the 20th power) Wcm{sup -2} and the heating produced at depth by hot electrons have been measured. Efficient generation of hot electrons but less than the anticipated heating have been observed.

Key, M.H.; Estabrook, K.; Hammel, B. [and others

1997-12-01

198

Hot Flow Anomalies at Venus  

NASA Astrophysics Data System (ADS)

We present a multi-instrument study of a Hot Flow Anomaly (HFA) observed by the Venus Express spacecraft in the Venutian foreshock, expanding on an initial study by Slavin et al [2009] that employed magnetometer observations of an HFA-like event during the flyby of NASA's Messenger spacecraft. Whilst the Messenger events were indicative of an HFA, they were unable to demonstrate the unambiguous signatures of plasma heating or deflection due to the paucity of data. We examine the complex internal structure of a Venutian HFA on the 22nd of March 2008, incorporating both Venus Express magnetometer and ASPERA plasma observations to demonstrate the presence of plasma heating within one such event. Centered on an interplanetary discontinuity and bounded by shock, the properties of this event are consistent with those of HFA's observed at other planets within the Solar System. Finally, we present a discussion of the implications of an HFA on the planet Venus.

Collinson, G. A.; Sibeck, D. G.; Masters, A.; Shane, N.; Slavin, J. A.; Coates, A. J.; Zhang, T.; Boardsen, S. A.; Moore, T. E.; Barabash, S.

2011-12-01

199

Hot-solvent miscible displacement  

SciTech Connect

This work describes an experimental and theoretical investigation of miscible displacement under nonisothermal conditions. The hot miscible floods were performed in an adiabatic glass bead pack, displacing one hydrocarbon by a more viscous hydrocarbon, the latter being at an elevated temperature. As a result, dispersion of both mass and heat took place, and was determined by temperature and concentration measurements. The system was simulated by coupled convective-diffusion and thermal conduction-convection equations. The results of the numerical as well as an approximate analytical solution were compared with the experimentally observed behavior. The numerical and experimental results point to the factors which should be considered in the choice of a solvent for a thermal-miscible type oil recovery process.

Awang, M.; Farouq Ali, S.M.

1980-01-01

200

Hot plasmas in the magnetosphere  

NASA Astrophysics Data System (ADS)

The dynamics and properties of plasmas of energies from a few tens of eV to 100 keV, by which the solar wind transfers mass, momentum and energy to the magnetosphere, are discussed. Particular attention is given to the transport processes occurring through the plasma sheet boundary layer and magnetospheric boundary layer, magnetic field line reconnection at neutral lines as a model for magnetospheric substorms, the solar-wind magnetosphere coupling function and interactions of magnetosheath plasma with ambient magnetospheric plasma in the magnetospheric boundary layer. The hot plasmas in the plasma source regions are noted to have higher densities and lower temperatures than those in the storage regions, while those in the transport regions have intermediate densities and temperatures and often exhibit anisotropies and gradients, as well as enhanced electrostatic wave emission and electric currents. The importance of the outer magnetosphere for studies in collisionless plasma physics is emphasized.

Eastman, T. E.; Frank, L. A.

201

HotDocs Doc Library  

NSDL National Science Digital Library

To find compelling documentaries from Canadians of all backgrounds and perspectives, one need go no further than the HotDocs Doc Library website. The library is entirely free, and visitors can get started by clicking on one of the four "communities" areas on the homepage. They include "YouthZone", "Educators", "Most Popular", and "Playlists". In the "YouthZone", visitors can view films by and for young filmmakers, such as the social critique found in "Everywhere, Advertisements" and a film on the high price of organic goods titled "Organic Matters". Teachers will appreciate the "Educators" area, which, along with various documentaries, also contains some study exercises titled "Why are Documentaries Worth Watching?" and "What Should We Look for in a Documentary?" Additionally, visitors can just go ahead and use the "Browse" area to look through over 200 films.

202

TRUEX hot demonstration. Final report  

SciTech Connect

In FY 1987, a program was initiated to demonstrate technology for recovering transuranic (TRU) elements from defense wastes. This hot demonstration was to be carried out with solution from the dissolution of irradiated fuels. This recovery would be accomplished with both PUREX and TRUEX solvent extraction processes. Work planned for this program included preparation of a shielded-cell facility for the receipt and storage of spent fuel from commercial power reactors, dissolution of this fuel, operation of a PUREX process to produce specific feeds for the TRUEX process, operation of a TRUEX process to remove residual actinide elements from PUREX process raffinates, and processing and disposal of waste and product streams. This report documents the work completed in planning and starting up this program. It is meant to serve as a guide for anyone planning similar demonstrations of TRUEX or other solvent extraction processing in a shielded-cell facility.

Chamberlain, D.B.; Leonard, R.A.; Hoh, J.C.; Gay, E.C.; Kalina, D.G.; Vandegrift, G.F.

1990-04-01

203

Variational Theory of Hot Dense Matter  

ERIC Educational Resources Information Center

|We develop a variational theory of hot nuclear matter in neutron stars and supernovae. It can also be used to study charged, hot nuclear matter which may be produced in heavy-ion collisions. This theory is a generalization of the variational theory of cold nuclear and neutron star matter based on realistic models of nuclear forces and pair…

Mukherjee, Abhishek

2009-01-01

204

Surface analytical studies of hot rolled aluminum  

Microsoft Academic Search

Studies of the oxide films on ingot and hot rolled aluminum surfaces show that mean oxide film thickness on a commercial purity (99.5%) metal surface is reduced considerably as a result of rolling on the breakdown mill of a conventional hot rolling line. Further reduction in oxide film thickness occurs during the subsequent passage of the metal through the three-stand

J. A. Treverton; J. Ball

1994-01-01

205

The role of serotonin in hot flushes  

Microsoft Academic Search

Hot flushes are experienced in those periods of the female life when estrogen levels are low. Hormone replacement therapy is thus the first choice for treatment of hot flushes. However this treatment is not always accepted or contraindicated for a variety of reasons. Estrogen (and progestogen) strongly interact with a number of neurotrans- mitters and this has led to a

Hemmie H. G. Berendsen

206

Atlas of Chandra Hot Star Spectra  

Microsoft Academic Search

The Chandra Observatory is obtaining transmission grating spectra of many hot stars. We present a prototype of Chandra Spectral Atlas of Hot Stars, which will include publicly available grating spectra of WR, O, and B stars of representative spectral classes. Currently, there are 20 HETG spectra of 14 unique objects in the archives which will all be public within a

N. R. Evans; J. Slavin; V. Kashyap; J. Nichols; E. Schlegel; M. Yukita

2002-01-01

207

Hot Dry Rock Geothermal Energy Development Program  

Microsoft Academic Search

During Fiscal Year 1987, emphasis in the Hot Dry Rock Geothermal Energy Development Program was on preparations for a Long-Term Flow Test'' of the Phase II'' or Engineering'' hot dry rock energy system at Fenton Hill, New Mexico. A successful 30-day flow test of the system during FY86 indicated that such a system would produce heat at a temperature and

M. C. Smith; R. H. Hendron; H. D. Murphy; M. G. Wilson

1989-01-01

208

VALIDATION OF HOT2000™ USING HERS BESTEST  

Microsoft Academic Search

HOT2000™, a residential energy analysis program, is constantly under evolution. New models are added to the program and its user base is ever expanding. As such it is important to continuously validate the program and ensure that it will be useful in its intended markets. To this end, HOT2000™ has been run through the HERS BESTEST, a comparative testing method

Debra Haltrecht; Kathleen Fraser

2000-01-01

209

Transfer of hot dry rock technology  

Microsoft Academic Search

The Hot Dry Rock Geothermal Energy Development Program has focused worldwide attention on the facts that natural heat in the upper part of the earth's crust is an essentially inexhaustible energy resource which is accessible almost everywhere, and that practical means now exist to extract useful heat from the hot rock and bring it to the earth's surface for beneficial

1985-01-01

210

Hot spot cooling using embedded thermoelectric coolers  

Microsoft Academic Search

Localized areas of high heat flux on microprocessors produce hot spots that limit their reliability and performance. With increasingly dense circuits and the integration of high power processors with low power memory, non-uniform thermal profiles will become more dramatic and difficult to manage. Chip scale thermal solutions designed to keep hot spots below a critical temperature unnecessarily overcool the rest

G. Jeffrey Snyder; Marco Soto; Randy Alley; David Koester; Bob Conner

2006-01-01

211

HotSpot Software Test Plan  

SciTech Connect

This Software Test Plan (STP) describes the procedures used to verify and validate that the HotSpot Health Physics Codes meet the requirements of its user base, which includes: (1) Users of the PC version of HotSpot conducting consequence assessment, hazard assessment and safety analysis calculations; and (2) Users of the NARAC Web and iClient software tools, which allow users to run HotSpot for consequence assessment modeling. This plan is intended to meet Critical Recommendation 2 from the Software Evaluation of HotSpot and DOE Safety Software Toolbox Recommendation for inclusion of HotSpot in the Department of Energy (DOE) Safety Software Toolbox. These users and sponsors of the HotSpot software and the organizations they represent constitute the intended audience for this document. HotSpot software is maintained for the Department of Energy Office of Emergency Operations by the National Atmospheric Release Advisory Center (NARAC) at Lawrence Livermore National Laboratory (LLNL). An overview of HotSpot and NARAC are provided.

Walker, H; Homann, S G

2009-03-12

212

HotSpot Software Configuration Management Plan  

SciTech Connect

This Software Configuration Management Plan (SCMP) describes the software configuration management procedures used to ensure that the HotSpot dispersion model meets the requirements of its user base, which includes: (1) Users of the PC version of HotSpot for consequence assessment, hazard assessment and safety analysis calculations; and (2) Users of the NARAC Web and iClient software tools, which allow users to run HotSpot for consequence assessment modeling These users and sponsors of the HotSpot software and the organizations they represent constitute the intended audience for this document. This plan is intended to meet Critical Recommendations 1 and 3 from the Software Evaluation of HotSpot and DOE Safety Software Toolbox Recommendation for inclusion of HotSpot in the Department of Energy (DOE) Safety Software Toolbox. HotSpot software is maintained for the Department of Energy Office of Emergency Operations by the National Atmospheric Release Advisory Center (NARAC) at Lawrence Livermore National Laboratory (LLNL). An overview of HotSpot and NARAC are provided.

Walker, H; Homann, S G

2009-03-12

213

Tribology during Hot, Flat Rolling of Steels  

Microsoft Academic Search

Tribology, defined to include the transfer of heat and forces at the surface of contact, is studied. The parameters affecting hot tribology are presented and discussed. An optical technique is used to monitor the forward slip during hot rolling, in air, of low carbon steel slabs. The forward slip is then related to the coefficient of friction by a finite

P. Munther; J. G. Lenard

1995-01-01

214

Validation of the Hot Strip Mill Model  

Microsoft Academic Search

The Hot Strip Mill Model (HSMM) is an off-line, PC based software originally developed by the University of British Columbia (UBC) and the National Institute of Standards and Technology (NIST) under the AISI\\/DOE Advanced Process Control Program. The HSMM was developed to predict the temperatures, deformations, microstructure evolution and mechanical properties of steel strip or plate rolled in a hot

Richard Shulkosky; David Rosberg; Jerrud Chapman

2005-01-01

215

Simulation on hot drug perfusion machine system  

Microsoft Academic Search

In the research of hot drug perfusion machine, temperature control is very important. Hot drugs acting on the lesion is a direct impact on the efficacy of the patience. So the application of Intelligent control which is called Fuzzy Adaptive PID is developed to dynamically adjust parameters according to the real-time information. The purpose is achieving a low over shoot,

Zhao Xinzhong; Wu Di

2010-01-01

216

The hot dry rock geothermal energy program  

SciTech Connect

The paper presents a simplified description of the Department of Energy's Hot-Dry-Rock program conducted at Fenton Hill, New Mexico. What a hot-dry-rock resource is and what the magnitude of the resource is are also described.

Smith, M.C.

1987-09-01

217

Basics of Solar Heating & Hot Water Systems.  

ERIC Educational Resources Information Center

|In presenting the basics of solar heating and hot water systems, this publication is organized from the general to the specific. It begins by presenting functional and operational descriptions of solar heating and domestic hot water systems, outlining the basic concepts and terminology. This is followed by a description of solar energy…

American Inst. of Architects, Washington, DC.

218

Hot particles: Risks, regulations and alara  

Microsoft Academic Search

In recent years, few areas of health physics have involved as many issues, problems and concerns as exposures of workers to hot particles. Current practices and responses to hot particle contaminations and exposure events have prompted many health physicists and regulators to consider the meaning of ALARA, uniform versus nonuniform exposures, stochastic versus nonstochastic health effects and the concept of

S. E. Merwin; M. P. Moeller

1989-01-01

219

Enabling Technologies for Ceramic Hot Section Components  

Microsoft Academic Search

Silicon-based ceramics are attractive materials for use in gas turbine engine hot sections due to their high temperature mechanical and physical properties as well as lower density than metals. The advantages of utilizing ceramic hot section components include weight reduction, and improved efficiency as well as enhanced power output and lower emissions as a result of reducing or eliminating cooling.

Venkat Vedula; Tania Bhatia

2009-01-01

220

Residential hot water solar energy storage subsystems  

Microsoft Academic Search

Low-cost, efficient, and practical hot water solar energy storage subsystems for heating and cooling of residences are discussed. Both new and innovative vessel materials and configurations are investigated, together with insulation materials. Storage subsystem locations considered include basement, crawl-space, living space, garage, attic, surface exterior and underground exterior. Performance requirements for residential hot water storage systems are investigated. A matrix

E. E. Pickering

1976-01-01

221

Performance of solar energy hot water systems  

Microsoft Academic Search

The results of performance comparisons of four solar hot water\\/building heat installations of the National Solar Data Network are presented. The sites were monitored by various sensors and data were processed remotely at a central location. Statistics are presented for seasonal hot water demand, solar fraction, fuel saved, supply and delivery temperatures, auxiliary fuel required, and costs, in addition to

M. A. Cramer; K. D. Evans; J. M. Rosenbusch; R. A. Weinstein

1981-01-01

222

Basics of Solar Heating & Hot Water Systems.  

ERIC Educational Resources Information Center

In presenting the basics of solar heating and hot water systems, this publication is organized from the general to the specific. It begins by presenting functional and operational descriptions of solar heating and domestic hot water systems, outlining the basic concepts and terminology. This is followed by a description of solar energy utilization…

American Inst. of Architects, Washington, DC.

223

New Hot-Electron Negative Resistance Effect  

Microsoft Academic Search

A new type of negative resistance effect is described. This effect arises from the properties of hot electrons in a material with a band structure consisting of several nonspherical valleys. A semiempirical theory is developed for this effect, based on a model for hot-electron behavior which assumes (1) that the mobility and \\

E. Erlbach

1963-01-01

224

Geology Fieldnotes: Hot Springs National Park, Arkansas  

NSDL National Science Digital Library

This National Park Service (NPS) site provides information about Hot Springs National Park in Arkansas, including geology, photographs, park maps, and visitor information. The cold and hot (143 degrees Farenheit) springs are a big attraction here, having existed for some 4,000 years. This site describes the springs here as well as the hydrothermal process that heats the water of the springs.

225

Hot Dry Rock Geothermal Energy Technology  

NSDL National Science Digital Library

This site helps to explain Hot Dry Rock (HDR) Technology, which harnesses geothermal energy to produce electricity. The website contains images and information about how hot dry rock technology is being used all over the world. The site also provides a list of contacts and additional related websites.

2007-07-20

226

Yellowstone: A continental midplate (hot spot) swell  

NASA Astrophysics Data System (ADS)

The Yellowstone hot spot has been identified mainly by its track of age-progressive volcanics; many smaller scale tectonic features serve to hide the long-wavelength hot spot-related swell. By employing averaging and filtering techniques, we are able to identify a swell in both the gravity and topography and use them to constrain the apparent depth of compensation of the Yellowstone hot spot at 70 +/- 10 km. This value is comparable to the deepest compensation depths for swells on old oceanic lithosphere. A compensation depth within the mid- to lower lithosphere combined with the only 15 m.y. known duration of the hot spot suggests either dynamic thinning of the thermal plate or compensation by upwelling in a low-viscosity asthenosphere, with some combination of the two explanations being consistent with seismic tomography results. Thus in many ways the Yellowstone hot spot appears quite similar to the oceanic analoges.

Waschbusch, P. J.; McNutt, M. K.

1994-08-01

227

1. EXTERIOR VIEW OF BUILDING THAT HOUSES THE HOT ROLL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. EXTERIOR VIEW OF BUILDING THAT HOUSES THE HOT ROLL MILL, ALSO KNOWN AS THE NO. 31 HOT ROLL MILL; LOOKING SOUTHWEST - American Brass Company, Kenosha Works, Hot Roll Mill, Kenosha, Kenosha County, WI

228

14 CFR 25.961 - Fuel system hot weather operation.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Fuel system hot weather operation. 25.961 Section 25...System § 25.961 Fuel system hot weather operation. (a) The fuel system must perform satisfactorily in hot weather operation. This must be...

2013-01-01

229

7 CFR 305.22 - Hot water immersion treatment schedules.  

Code of Federal Regulations, 2010 CFR

...2009-01-01 false Hot water immersion treatment schedules. 305.22...Treatments § 305.22 Hot water immersion treatment schedules. (a) T102-d...water's surface in a hot water immersion treatment tank certified by...

2009-01-01

230

7 CFR 305.22 - Hot water immersion treatment schedules.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Hot water immersion treatment schedules. 305.22...Treatments § 305.22 Hot water immersion treatment schedules. (a) T102-d...water's surface in a hot water immersion treatment tank certified by...

2010-01-01

231

Hot Gas in the Large Magellanic Cloud  

NASA Astrophysics Data System (ADS)

Massive stars interact with the interstellar medium (ISM) via UV radiation, fast stellar winds, and supernova ejecta. These energetic interactions ionize, accelerate, and heat the ISM, producing hot gas with temperatures up to 10^7 K. The mass exchange between this hot gas and the cold neutral gas constitutes the evolution of a multi-phase ISM. Hot ionized gas is an essential component of the ISM. However, it is difficult to study the distribution and physical properties of hot gas in the Galaxy because of confusion and obscuration along the Galactic plane. The Large Magellanic Cloud (LMC), owing to its close proximity, nearly face-on view, and small extinction, presents an ideal site to study hot gas and its role in the interstellar matrix. Soft X-ray images of the LMC show bright diffuse emission, indicating the existence of hot (10^6-10^7 K) ionized gas. Clues to the origin of the hot gas in the LMC are provided by comparisons between X-ray and H-alpha images. H-alpha images of the LMC show a variety of interstellar shells, ranging from small supernova remnants a few pc in diameter to large supergiant shells more than 1000 pc across. Some of the diffuse X-ray emission is associated with shell structures, but there is also large-scale diffuse emission that does not appear to be confined by any cooler interstellar structures. The origins of hot gas in these different types of diffuse X-ray emission regions are individually discussed. A hot (10^5 K) gas halo of the LMC was suggested in the early 1980's. As most of the previously reported interstellar C IV absorption occurs in large shell structures where supernovae and fast stellar winds are rampant, the evidence for a global hot gas halo around the LMC has been weak. Recent HST GHRS observations of five carefully chosen probe stars show clear detections of the interstellar C IV, providing unambiguous evidence for a hot gas halo of the LMC. Three sightlines have C IV velocities blue shifted from the H-alpha by 25-60 km s/1, indicating that the hot gas halo may be expanding away from the disk gas. The hot gas halo of the LMC is most likely patchy, as implied by a stringent nondetection by the IUE along one sightline.

Chu, Y.-H.

1998-12-01

232

NASA helps reduce city hot spots  

NASA Astrophysics Data System (ADS)

When researchers from NASA's Marshall Space Flight Center in Huntsville, Ala., recently flew a thermal camera, mounted on a NASA aircraft, over Baton Rouge, La., Sacramento, Calif., and Salt Lake City, Utah, they took each city's temperature and produced an image that pinpoints the cities' "hot spots."Now, the researchers are using the images to study what types of surfaces in cities contribute to bubble-like accumulations of hot air, called urban heat islands. The bubbles of hot air develop over cities as naturally vegetated surfaces are replaced with asphalt, concrete, rooftops, and other man-made materials.

Showstack, Randy

233

Hot Leg Piping Materials Issues  

SciTech Connect

With Naval Reactors (NR) approval of the Naval Reactors Prime Contractor Team (NRPCT) recommendation to develop a gas cooled reactor directly coupled to a Brayton power conversion system as the space nuclear power plant (SNPP) for Project Prometheus (References a and b) the reactor outlet piping was recognized to require a design that utilizes internal insulation (Reference c). The initial pipe design suggested ceramic fiber blanket as the insulation material based on requirements associated with service temperature capability within the expected range, very low thermal conductivity, and low density. Nevertheless, it was not considered to be well suited for internal insulation use because its very high surface area and proclivity for holding adsorbed gases, especially water, would make outgassing a source of contaminant gases in the He-Xe working fluid. Additionally, ceramic fiber blanket insulating materials become very friable after relatively short service periods at working temperatures and small pieces of fiber could be dislodged and contaminate the system. Consequently, alternative insulation materials were sought that would have comparable thermal properties and density but superior structural integrity and greatly reduced outgassing. This letter provides technical information regarding insulation and materials issues for the Hot Leg Piping preconceptual design developed for the Project Prometheus space nuclear power plant (SNPP).

V. Munne

2006-07-19

234

Grain evolution during hot forging  

NASA Astrophysics Data System (ADS)

A review on grain evolution during hot forging is presented in this paper. The discussion focus is on the experimental law, the microscopic mechanism, the physical model and the evolution equations of grain refinement and growth. This is because the grain evolution is the most important microstructure evolution effecting on the part mechanical behaviors, and to establish reasonable grain evolution is a very important and difficult work for macro microscopic coupling constitutive equation. The following contents about constitutive equation and grain evolution are discussed. 1) The experimental phenomena and evolution laws of grain growth and grain refinement under differential working conditions (deformation, heating, cooling) in order to adapt to the needs of numerical simulation of whole forging process. 2) The advantages and disadvantages of the traditional empirical equations on grain growth, grain refinement and recrystallization process are analyzed. 3) The recent advances in physic models for dynamic recrystallizaton and dynamic grain growth are introduced in detail. Comparing to the empirical equations, these models are closer to the actual physical process. The models not only describe the details of grain changes, but also reveal the relationship between the accumulated dislocations energy and grain size evolution. In addition, the assumptions used in the models and their influences on prediction function are also discussed in order to improve the models.

Jin, Quanlin

2013-05-01

235

Iron Aluminide Hot Gas Filters  

SciTech Connect

Currently, high temperature filter systems are in the demonstration phase with the first commercial scale hot filter systems being installed on integrated gasification combined cycle (IGCC) and pressurized fluid bed combustion cycle (PBFC) systems (70 MW). They are dependent on the development of durable and economic high temperature filter systems. These filters are mostly ceramic tubes or candles. Ceramic filter durability has not been high. Failure is usually attributed to mechanical or thermal shock: they can also undergo significant changes due to service conditions. The overall objective of this project is to commercialize weldable, crack resistant filters which will provide several years service in advanced power processes. The specific objectives of this project are to develop corrosion resistant alloys and manufacturing processes to make Iron Aluminide filter media, and to use a ``short term`` exposure apparatus supported by other tests to identify the most promising candidate (alloy plus sintering cycle). The objectives of the next phases are to demonstrate long term corrosion stability for the best candidate followed by the production of fifty filters (optional).

Hurley, J.; Brosious, S.; Johnson, M. [Pall Process Equipment Development Div., Pall Corp., Cortland, NY (United States)

1996-12-31

236

Filter for cleaning hot gases  

SciTech Connect

In an apparatus for cleaning hot gases a filter housing has an inlet for unfiltered gas and an outlet for filtered gas. A plurality of filtered inserts are placed within the housing in a manner capable of filtering undesirable components from the gas feed stream. Each filter insert is made of a fibrous filter material. Silicic-acid glass fibers have a silicic acid content of at least 90%. Coated upon the fibers and absorbed into their pores is a metal oxide of aluminum, titanium, zirconium, cromium, nickle or cobalt. A honeycombed cage filled with high temperature resistant perlite is located within the housing between the gas inlet and the fiber inserts. The cage has an inlet and outlet external to the housing for replacing the perlite. A combustion chamber mounted in the housing has a discharge nozzle located so that the nozzle is directed at the filter inserts. Combusting materials in the chamber causes an explosive backflow of gases through the filter inserts.

Gresch, H.; Holter, H.; Hubner, K.; Igelbuscher, H.; Weber, E.

1981-10-20

237

Phage Community Dynamics in Hot Springs  

PubMed Central

In extreme thermal environments such as hot springs, phages are the only known microbial predators. Here we present the first study of prokaryotic and phage community dynamics in these environments. Phages were abundant in hot springs, reaching concentrations of a million viruses per milliliter. Hot spring phage particles were resistant to shifts to lower temperatures, possibly facilitating DNA transfer out of these extreme environments. The phages were actively produced, with a population turnover time of 1 to 2 days. Phage-mediated microbial mortality was significant, making phage lysis an important component of hot spring microbial food webs. Together, these results show that phages exert an important influence on microbial community structure and energy flow in extreme thermal environments.

Breitbart, Mya; Wegley, Linda; Leeds, Steven; Schoenfeld, Tom; Rohwer, Forest

2004-01-01

238

Hot Dry Rock Geothermal Prospects, 1981.  

National Technical Information Service (NTIS)

The hot dry rock (HDR) site selection and resource evaluation team has been assessing roughly 24 sites within the USA as candidates for development of a second HDR geothermal system. Potential sites examined fall broadly into three categories according to...

F. E. Goff A. W. Laughlin J. Aldrich

1981-01-01

239

Geothermal hot water transportation and utilization system  

SciTech Connect

A geothermal hot water transportation system is described for transporting geothermal hot water from underground to above ground. The system consists of: means for pressurizing and pumping hot water from a geothermal production well to a location above ground including a downhole pump for installation in the geothermal production well, and a long downhole pump shaft; a pump casing having a below surface end connected to the downhole pump and an above surface end; means for separating steam and hot water brought to the surface from the well by the downhole pump through the pump casing, including an above ground rotary separation two-phase flow turbine communicating with the above surface end of the pump casing, the two-phase flow turbine having a power output shaft means for directly powering the downhole pump through the downhole pump shaft.

Yamaoka, K.

1986-03-18

240

Bouncing Balls and Hot Rod Races.  

ERIC Educational Resources Information Center

|This paper presents the Bouncing Ball Experiment which models quadratic and exponential functions, and the Hot Rod Races activity that explores velocity and acceleration. Activities include directions for the use of TI-82 and TI-83 calculators. (YDS)|

Tibbs, Peggy; Sherrill, Donna

241

Kepler Constraints on Planet near Hot Jupiters.  

National Technical Information Service (NTIS)

We present the results of a search for planetary companions orbiting near hot Jupiter planet candidates (Jupiter-size candidates with orbital periods near 3 d) identified in the Kepler data through its sixth quarter of science operations. Special emphasis...

A. P. Boss D. Ragozzine D. C. Fabrycky D. R. Ciardi E. B. Ford J. A. Carter J. F. Rowe J. H. Steffen M. J. Holman S. N. Quinn W. F. Welsh W. J. Borucki

2012-01-01

242

Bibliography on Hot Isostatic Pressing (HIP) Technology.  

National Technical Information Service (NTIS)

This report contains an annotated bibliography of 950 documents on the Hot Isostatic Pressing (HIP) Technology dealing with metals, alloys, and intermetallic compounds and covers over 450 materials. Documents published from 1966 to early 1992 are covered....

B. F. Gilp C. Y. Ho J. F. Radavich P. D. Desai

1992-01-01

243

Insulator hot washing with deionized water  

Microsoft Academic Search

The evolution of hot washing insulators with deionized water is reviewed and the most recent washing equipment and practices are described. The effect of increasing the effective washing distance through the use of \\

Jamison C. Johnson

1976-01-01

244

Prototype Solar Domestic Hot Water Systems.  

National Technical Information Service (NTIS)

Construction of a double wall heat exchanger using soft copper tube coiled around a hot water storage tank was completed and preliminary tests were conducted. Solar transport water to tank potable water heat exchange tests were performed with a specially ...

1978-01-01

245

Hot water immersion for bluebottle stings.  

PubMed

Hot water immersion can be used to treat bluebottle (Physalia spp.) stings. Bluebottle stings are most common in non-tropical areas and can be very painful. After initial management, hot water (ideally at 42-45°C) applied to the site of the sting for 30-90 minutes can be used to manage pain. If hot water is unavailable, a heat pack may provide an accessible alternative. Hot water application for bluebottle stings has NHMRC Level 2 evidence of efficacy. The most common adverse effect is that the patient cannot tolerate the heat, and there has been one case of a thermal burn reported. This article forms part of a series on non-drug treatments, which summarise the indications, considerations and the evidence, and where clinicians and patients can find further information. PMID:23781548

2013-06-01

246

A constant temperature hot-wire anemometer  

Microsoft Academic Search

A compact, inexpensive, constant temperature hot-wire anemometer circuit using solid state operational amplifiers is described. A theoretical expression for frequency response and an experimental check are given. Theoretical and experimental response data for an existing unit are shown.

J C Wyngaard; J L Lumley

1967-01-01

247

Hedonic hot spots in the brain.  

PubMed

Hedonic "liking" for sensory pleasures is an important aspect of reward, and excessive 'liking' of particular rewards might contribute to excessive consumption and to disorders such as obesity. The present review aims to summarize recent advances in the identification of brain substrates for food 'liking' with a focus on opioid hot spots in the nucleus accumbens and ventral pallidum. Drug microinjection studies have shown that opioids in both areas amplify the 'liking' of sweet taste rewards. Modern neuroscience tools such as Fos plume mapping have further identified hedonic hot spots within the accumbens and pallidum, where opioids are especially tuned to magnify 'liking' of food rewards. Hedonic hot spots in different brain structures may interact with each other within the larger functional circuitry that interconnects them. Better understanding of how brain hedonic hot spots increase the positive affective impact of natural sensory pleasures will help characterize the neural mechanisms potentially involved in 'liking' for many rewards. PMID:17079516

Peciña, Susana; Smith, Kyle S; Berridge, Kent C

2006-12-01

248

Hot electron effect in ultrathin photovoltaic devices  

NASA Astrophysics Data System (ADS)

The focus of the research work described in the following thesis is increasing the efficiency of photovoltaic devices by reducing hot carrier thermalization losses. In principle this can be achieved by reducing the size of the absorber down to lengths comparable to the thermalization length for hot carriers. With the use of ultrathin absorbers hot carrier can be collected before they have reached thermal equilibrium with the lattice. The theoretical work on the subject is comprised of improving the empirical relationship developed in the most recent publication on the topic by. By making the assumption that the energy loss rate fits the exponential decay model, an expression for the energy as a function of absorber thickness was developed. The experimental work consist of fabricating devices with different absorber thicknesses and testing their ability to show change in performance due to collection of hot electrons.

Mihaylov, Deyan Ivov

249

Hot-Wire Synthesis of Gold Nanoparticles  

Microsoft Academic Search

Gold nanoparticles were synthesized by a hot-wire generator at atmospheric pressure using a gold-platinum composite wire. At low gas flow velocities the nanoparticles were found to be agglomerates of partially sintered primary particles. By reducing the tube size via the insertion of a nozzle with a throat diameter of 3 mm, the hot-wire generator was found to produce small (<10

Adam M. Boies; Pingyan Lei; Steven Calder; Weon Gyu Shin; Steven L. Girshick

2011-01-01

250

Electron scattering in hot-dense plasmas  

NASA Astrophysics Data System (ADS)

Hot-dense plasmas have direct industrial applications in inertial confinement fusion. We have used the convergent close-coupling (CCC) method to investigate electron scattering off hydrogen and helium atoms in a hot-dense weakly coupled (Debye) plasma. The Yukawa-type Debye-Hückel potential has been used to describe the plasma screening effects. Integrated excitation, total ionization and total cross sections have been calculated over a broad range of energies and various Debye lengths, D.

Zammit, Mark C.; Fursa, Dmitry V.; Bray, Igor

2012-11-01

251

Hot corrosion behavior of Nimonic75  

Microsoft Academic Search

Hot corrosion studies were conducted on Nimonic-75 superalloy in pure NaâSOâ and 90% NaâSOâ + 10% NaCl environments at 900 C for different time intervals. The results showed that Nimonic-75 exhibits good hot corrosion resistance in pure sodium sulfate, and the corrosion rate was enhanced considerably in the presence of 10% NaCl environment. It is also evident that the corrosion

Gurrappa

1997-01-01

252

THz hot-electron photon counter  

Microsoft Academic Search

We discuss an implementation of a hot-electron transition-edge sensor (TES) capable of counting THz photons. The main need for such a THz calorimeter is spectroscopy on future space telescopes with a background limited NEP?10-20 W\\/Hz12\\/. The micromachined bolometers will unlikely reach such sensitivity at temperatures above 10 mK. The hot-electron TES with sufficient sensitivity will still have a time constant

Boris S. Karasik; Andrei V. Sergeev

2005-01-01

253

Hot Corrosion in a Temperature Gradient  

SciTech Connect

Hot corrosion is the accelerated attack of materials at elevated temperatures that is induced by a thin film of fused salt. Many materials that experience hot corrosion are exposed to high heat fluxes and temperature gradients. The hot corrosion of metals can be described by the dissolution of a protective metal oxide into the fused salt and the subsequent precipitation of the metal oxide in a non-protective form. Rapp and Goto have established a criterion for the sustained hot corrosion of a pure metal that the solubility gradient of the protective oxide in the salt film must be negative at the oxide/salt interface. The influence of a temperature gradient on the metal oxide solubility gradient (and the predicted hot corrosion susceptibility) is discussed. Solubility data for NiO and Na{sub 2}SO{sub 4} are used to illustrate the effects of a temperature gradient. The effects of a temperature gradient were determined by examining various combinations of dissolution reactions, oxidants, and transport kinetics. Based on these results, and the thinness of the molten salt films, temperature gradients are not expected to be of importance to hot corrosion fluxing mechanisms.

Holcomb, G.R.

1999-04-01

254

Turbine and hot gas cleanup at Wilsonville  

SciTech Connect

Southern Company Services, Inc. (SCS) has entered into an agreement with the Department of Energy, Morgantown Energy Technology Center (DOE/METC) to design, construct and operate the Hot Gas Cleanup Test Facility for Gasification and Pressurized Combustion. The purpose is to identify and evaluate potential hot particulate cleanup systems on a scale large enough so that these systems can be related to potential commercial system. This entails first developing the criteria for engineering-scale testing of hot particulate control devices which will lead to the design, construction and operation of a flexible test facility capable of operating under gasification and PFBC conditions. This will allow the testing of particulate control devices (PCDs) under realistic conditions in terms of gas composition, temperature, pressure, particulate loading and operating duration. The conceptual design of the Hot Gas Cleanup Test Facility Project was expanded to include additional modules to better address the scope of the Cooperative Agreement with the DOE/METC. The expanded test facility, referred to as the Power Systems Development Facility (PSDF), will provide a flexible test location in which the development of advanced power system components, the evaluation of advanced turbine and fuel cell configurations, and the integration and control issues of these systems. The facility is intended to provide direct support for upcoming DOE demonstrations of power generation technologies utilizing hot stream cleanup and will provide a resource for rigorous testing and performance assessment of hot stream cleanup devices now being developed with the support of DOE/METC.

Sears, R.E.; Griswold, G.H. [Southern Co. Services, Inc., Birmingham, AL (United States); Fankhanel, M.O. [Kellogg (M.W.) Co. (United States); Kastner, C.E. [Foster Wheeler Corp. (United States); Pontius, D.H. [SRI International, Menlo Park, CA (United States)

1993-01-01

255

Hot Corrosion in a Temperature Gradient  

SciTech Connect

Hot corrosion is the accelerated attack of materials at elevated temperatures that is induced by a thin film of fused salt. Many materials that experience hot corrosion are exposed to high heat fluxes and temperature gradients. The hot corrosion of metals can be described by the dissolution of a protective metal oxide into the fused salt and the subsequent precipitation of the metal oxide in a non-protective form. Rapp and Goto have established a criterion for the sustained hot corrosion of a pure metal that the solubility gradient of the protective oxide in the salt film must be negative at the oxide/salt interface. The influence of a temperature gradient on the metal oxide solubility gradient (and the predicted hot corrosion susceptibility) is discussed. Solubility data for NiO in Na{sub 2}SO{sub 4} are used to illustrate the effects of a temperature gradient. The effects of a temperature gradient were determined by examining various combinations of dissolution reactions, oxidants, and transport kinetics. Based on these results, and the thinness of the molten salt films, temperature gradients are not expected to be of importance to hot corrosion fluxing mechanisms.

Holcomb, G.R.

2000-08-01

256

Hot particles: Risks, regulations and alara  

SciTech Connect

In recent years, few areas of health physics have involved as many issues, problems and concerns as exposures of workers to hot particles. Current practices and responses to hot particle contaminations and exposure events have prompted many health physicists and regulators to consider the meaning of ALARA, uniform versus nonuniform exposures, stochastic versus nonstochastic health effects and the concept of dose as an estimation of risk. During this time period, health physicists have been forced to follow current regulations despite concerns that the regulations do not conform to the ALARA principle. The purpose of this paper is to highlight conflicts between the issues stated, such as ALARA, and the current requirements for assessing and recording hot particle exposure events. The significant points to be discussed in this paper are the low probability of a hot particle exposure causing a deleterious health effect, the inappropriateness of comparing extremely nonuniform hot particle exposures to dose limits for uniform exposures, and the inappropriateness of recording a hot particle dose in a worker's dose history as if it were a uniform exposure. 9 refs.

Merwin, S.E.; Moeller, M.P.

1989-06-01

257

Canopy hot-spot as crop identifier  

SciTech Connect

Illuminating any reflective rough or structured surface by a directional light source results in an angular reflectance distribution that shows a narrow peak in the direction of retro-reflection. This is called the Heiligenschein or hot-spot of vegetation canopies and is caused by mutual shading of leaves. The angular intensity distribution of the hot-spot, its brightness and slope, are therefore indicators of the plant's geometry. We propose the use of hot-spot characteristics as crop identifiers in satellite remote sensing because the canopy hot-spot carries information about plant stand architecture that is more distinctive for different plant species than, for instance, their spectral reflectance characteristics. A simple three-dimensional Monte Carlo/ray tracing model and an analytic two-dimensional model are developed to estimate the angular distribution of the hot-spot as a function of the size of the plant leaves. The results show that the brightness-distribution and slope of the hot-spot change distinctively for different leaf sizes indicating a much more peaked maximum for the smaller leaves.

Gerstl, S.A.W.; Simmer, C.; Powers, B.J.

1986-05-01

258

Failure analysis of hot forging dies for automotive components  

Microsoft Academic Search

Influencing variables and causes of hot forging die failures for automotive components are summarized. Characteristics of hot forging die failures are exemplified. An important role of microfractography is stressed in engineering failure analysis for hot forging die failures.Then failure analyzed examples for hot forging die failures and their countermeasures are presented with influencing variables such as die materials, die design,

Ryuichiro Ebara; Katsuaki Kubota

2008-01-01

259

Experimental study of deep drawability of hot rolled IF steel  

Microsoft Academic Search

The effects of the hot rolling conditions on the deep drawability of hot rolled interstitial-free (IF) steel were investigated in this paper. Experiments showed that the rolling lubrication affected the deep drawability of the hot rolled IF steel greatly. Without rolling lubrication, the hot rolled IF steel could not obtain deep drawability. Pass reduction also had a significant effect on

H Zhao; S. C Rama; G. C Barber; Z Wang; X Wang

2002-01-01

260

The Effectiveness of Hot-deck Procedures in Small Samples.  

ERIC Educational Resources Information Center

A simulation study was conducted to identify the best hot-deck variation to impute missing values. The three variations included in the study were the hot-deck random, the hot-deck sequential, and the hot-deck distance. The properties of these methods were investigated under three levels of the proportion of incomplete records and four levels…

Kaiser, Javaid

261

40 CFR 68.85 - Hot work permit.  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 2013-07-01 false Hot work permit. 68.85 Section 68.85...Program 3 Prevention Program § 68.85 Hot work permit. (a) The owner or operator shall issue a hot work permit for hot work operations...

2013-07-01

262

Physiological responses during continuous work in hot dry and hot humid environments in Indians  

NASA Astrophysics Data System (ADS)

Studies have been conducted on six young healthy heat acclimatised Indians to determine the physiological changes in prolonged continuous work in thermally neutral and in hot dry and hot humid environments. Physiological responses in maximal efforts i.e. Vo2 max, VE max and Cf max were noted. In addition, duration in continuous work at three sub-maximal rate of work in three simulated environments were also noted. Physiological responses like Vo2, VE and Cf were noted every 15 minutes of work. Besides these responses, rectal temperature (Tre), mean skin temperature (Ts) and mean sweat rate were also recorded during continuous work. Results indicated a significant decrease in maximum oxygen uptake capacity (Vo2 max) in heat with no change in maximum exercise ventilation (VE max) and maximum cardiac frequency. However, the fall in Vo2 max was more severe in the hot humid environment than in the hot dry climate. Cardiac frequency at fixed oxygen consumption of 1.0, 1.5 and 2.0 l/min was distinctly higher in the hot humid environment than in the hot dry and comfortable temperature. The duration in continuous physical effort in various grades of activities decreased in hot dry environment from that in the-comfortable climate and further decreased significantly in hot humid environment. The highest rate of sweating was observed during work in humid heat. The mean skin temperature (Ts) showed a fall in all the three rates of work in comfortable and hot dry conditions whereas in hot humid environment it showed a linear rise during the progress of work. The rectal temperature on the other hand maintained a near steady state while working at 65 and 82 watts in comfortable and hot dry environments but kept on rising during work in hot humid environment. At the highest work rate of 98 watts, the rectal temperature showed a steady increase even in the hot dry condition. It was thus concluded from the study that a hot humid climate imposes more constraints on the thermoregulatory system during work than in the hot dry condition because of less effective heat dissipation so resulting in reduced tolerance to work.

Sen Gupta, J.; Swamy, Y. V.; Pichan, G.; Dimri, G. P.

1984-06-01

263

Relationship between Hot Spot Residues and Ligand Binding Hot Spots in Protein-Protein Interfaces  

PubMed Central

In the context of protein-protein interactions, the term “hot spot” refers to a residue or cluster of residues that makes a major contribution to the binding free energy, as determined by alanine scanning mutagenesis. In contrast, in pharmaceutical research a hot spot is a site on a target protein that has high propensity for ligand binding and hence is potentially important for drug discovery. Here we examine the relationship between these two hot spot concepts by comparing alanine scanning data for a set of 15 proteins with results from mapping the protein surfaces for sites that can bind fragment-sized small molecules. We find the two types of hot spots are largely complementary; the residues protruding into hot spot regions identified by computational mapping or experimental fragment screening are almost always themselves hot spot residues as defined by alanine scanning experiments. Conversely, a residue that is found by alanine scanning to contribute little to binding rarely interacts with hot spot regions on the partner protein identified by fragment mapping. In spite of the strong correlation between the two hot spot concepts, they fundamentally differ, however. In particular, while identification of a hot spot by alanine scanning establishes the potential to generate substantial interaction energy with a binding partner, there are additional topological requirements to be a hot spot for small molecule binding. Hence, only a minority of hot spots identified by alanine scanning represent sites that are potentially useful for small inhibitor binding, and it is this subset that is identified by experimental or computational fragment screening.

Zerbe, Brandon S.; Hall, David R.

2013-01-01

264

ADVANCED HOT GAS FILTER DEVELOPMENT  

SciTech Connect

This report describes the fabrication and testing of continuous fiber ceramic composite (CFCC) based hot gas filters. The fabrication approach utilized a modified filament winding method that combined both continuous and chopped fibers into a novel microstructure. The work was divided into five primary tasks. In the first task, a preliminary set of compositions was fabricated in the form of open end tubes and characterized. The results of this task were used to identify the most promising compositions for sub-scale filter element fabrication and testing. In addition to laboratory measurements of permeability and strength, exposure testing in a coal combustion environment was performed to asses the thermo-chemical stability of the CFCC materials. Four candidate compositions were fabricated into sub-scale filter elements with integral flange and a closed end. Following the 250 hour exposure test in a circulating fluid bed combustor, the retained strength ranged from 70 t 145 percent of the as-fabricated strength. The post-test samples exhibited non-catastrophic failure behavior in contrast to the brittle failure exhibited by monolithic materials. Filter fabrication development continued in a filter improvement and cost reduction task that resulted in an improved fiber architecture, the production of a net shape flange, and an improved low cost bond. These modifications were incorporated into the process and used to fabricate 50 full-sized filter elements for testing in demonstration facilities in Karhula, Finland and at the Power Systems Development Facility (PSDF) in Wilsonville, AL. After 581 hours of testing in the Karhula facility, the elements retained approximately 87 percent of their as-fabricated strength. In addition, mechanical response testing at Virginia Tech provided a further demonstration of the high level of strain tolerance of the vacuum wound filter elements. Additional testing in the M. W. Kellogg unit at the PSDF has accumulated over 1800 hours of coal firing at temperatures of 760 °C including a severe thermal upset that resulted in the failure of several monolithic oxide elements. No failures of any kind have been reported for the MTI CFCC elements in either of these test campaigns. Additional testing is planned at the M. W. Kellogg unit and Foster Wheeler unit at the PSDF over the next year in order to qualify for consideration for the Lakeland PCFB. Process scale-up issues have been identified and manufacturing plans are being evaluated to meet the needs of future demand.

RICHARD A. WAGNER

1998-09-04

265

UV emissions of Hot Jupiters  

NASA Astrophysics Data System (ADS)

In the solar system, the giant planets Jupiter and Saturn have bright aurorae due to particle precipitation in the upper atmospheres. The brightest optical auroral emissions are emitted by H and H2 in the UV and by H3+ in the IR. Due to the short distance to the parent stars, hot Jupiters are likely to be bombarded by intense stellar winds and UV fluxes and have strong emissions at the same wavelengths. When detected, their UV emissions could bring helpful information to characterize the upper atmospheres of the exoplanets. The first question to address is : are these emissions bright enough to be observed from Earth and distinguished from the stellar UV emissions ? We focus on Jupiter-like atmospheres, composed of H, H2 and He. Kinetic calculations allow to estimate the electron flux throughout the atmosphere and to calculate excitation rates of the upper levels of UV transitions of H and H2. Radiative transfer calculations are then done to estimate the intensity of the emergent lines and the profile of the H Lyman alpha line. Using the Yelle (2004) atmosphere model for HD209458b, we evaluate the H Lyman alpha dayglow of the planet. We also evaluate UV emissions of the planet caused by the precipitation of particles with and without an intrinsec magnetic field. We find that the Lyman alpha emission of the planet could reach 1/1000 of that of the star. It has been shown that the profile of the H Lyman alpha line is very sensitive to the atmospheric model and to the energy of the precipitating electrons (Menager et al. 2010). We see here a way to constrain the upper atmosphere of exoplanets and their particle environment, that could be used by future UV telescopes. References R. Yelle, Aeronomy of extra-solar giant planets at small orbital distances, Icarus, volume 170, 2004 H. Menager, M. Barthélemy, and J. Lilensten, H Lyman alpha line in Jovian aurorae : electron transport and radiative transfer coupled modelling, Astronomy & Astrophysics, accepted

Ménager, Hélène; Mathieu, Barthélemy; Jean, Lilensten

2010-05-01

266

Experiments with the hot list strategy  

SciTech Connect

Experimentation strongly suggests that, for attacking deep questions and hard problems with the assistance of an automated reasoning program, the more effective paradigms rely on the retention of deduced information. A significant obstacle ordinarily presented by such a paradigm is the deduction and retention of one or more needed conclusions whose complexity sharply delays their consideration. To mitigate the severity of the cited obstacle, the author formulates and features in this report the hot list strategy. The hot list strategy asks the researcher to choose, usually from among the input statements, one or more clauses that are conjectured to play a key role for assignment completion. The chosen clauses - conjectured to merit revisiting, again and again - are placed in an input list of clauses, called the hot list. When an automated reasoning program has decided to retain a new conclusion C - before any other clause is chosen to initiate conclusion drawing - the presence of a nonempty hot list (with an appropriate assignment of the input parameter known as heat) causes each inference rule in use to be applied to C together with the appropriate number of members of the hot list. Members of the hot list are used to complete applications of inference rules and not to initiate applications. The use of the hot list strategy thus enables an automated reasoning program to briefly consider a newly retained conclusion whose complexity would otherwise prevent its use for perhaps many CPU-hours. To give evidence of the value of the strategy, the author focuses on four contexts: (1) dramatically reducing the CPU time required to reach a desired goal; (2) finding a proof of a theorem that had previously resisted all but the more inventive automated attempts; (3) discovering a proof that is more elegant than previously known; and (4) answering a question that had steadfastly eluded researchers relying on an automated reasoning program.

Wos, L.

1997-10-01

267

The production of ferritically hot rolled interstitial-free steel on a modern hot strip mill  

Microsoft Academic Search

Ferritic hot rolling was developed in the late 1980s through a desire to eliminate temperature control problems when rolling thin hot strip in the austenitic condition. This was accomplished by reducing the finishing temperature to allow rolling to take place with a wholly ferritic microstructure. It was soon discovered, however, that time and cost savings could be realised through this

C. J. Barrett; B. Wilshire

2002-01-01

268

A&M. Hot cell annex (TAN633) interior under construction. Hot cells ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

A&M. Hot cell annex (TAN-633) interior under construction. Hot cells and their doors are along concrete wall. Note side wall of pumice block. Photographer: Jack L. Anderson. Date: October 28, 1957. INEEL negative no. 57-5335 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

269

Geophysical Investigation of Neal Hot Springs  

NASA Astrophysics Data System (ADS)

We present newly acquired geophysical data that characterizes a geothermal system at Neal Hot Springs in eastern Oregon. The hot springs are in a region of complex and intersecting fault trends associated with two major extensional events, the Oregon-Idaho Graben and the western Snake River Plain. From surface observations and several boreholes in the area, it appears that a steeply dipping normal fault forms a half-graben basin and serves as a conduit for heated water at depth to migrate to the surface at Neal Hot Springs. We identify and characterize this fault with seismic reflection, gravity, magnetic, and electrical resistivity surveys. A self-potential survey indicates that water is upwelling over the fault plane, and suggests that the fault does provide the means for heated water to migrate to the surface. Smaller scale structure is also evident in both the gravity and seismic surveys, and could interact with the migration of water, and how the hot springs recharge. These preliminary results will be built upon in the upcoming years and a solid structural understanding of Neal Hot Springs and the surrounding area will be gained through the use of geophysics.

Colwell, C.; Van Wijk, K.; Liberty, L. M.

2011-12-01

270

Pore Collapse and Hot Spots in HMX  

NASA Astrophysics Data System (ADS)

Hot spots are critical for initation of explosives because reaction rates are very temperature sensitive. For a plastic-bonded explosive, shock desensitization experiments imply that hot spots generated by pore collapse dominate shock initiation. Here, for the collapse of a single pore driven by a shock, the dependence of the temperature distribution on numerical resolution and dissipative mechanism is investigated. An inert material (with the constitutive properties of HMX) is used to better focus on the mechanics of pore collapse. Two important findings result from this study. First, insufficient resolution can significantly overpredict the hot-spot mass. Second, up to moderate piston velocities (< 1 km/s), shock dissipation alone does not generate sufficient hot-spot mass for initiation. Two other dissipative mechanisms investigated are plastic work and viscous heating. In the cases studied, the integrated temperature distribution has a power-law tail with exponent related to a parameter with dimensions of viscosity. The parameter of either dissipative mechanism can be fit to obtain the hot-spot mass needed for initiation of any single experiment. However, the dissipative mechanisms scale differently with shock strength and pore size. Consequently, to predict initiation behavior over a range of stimuli and as the micro-structure properties of a PBX are varied, sufficient numerical resolution and the correct physical dissipative mechanism are essential.

Menikoff, Ralph

2004-07-01

271

Hot cell shield plug extraction apparatus  

DOEpatents

A hot cell installation for the handling of highly radioactive material may comprise a dozen or more interconnected high density concrete vaults, the concrete vault walls having a thickness of approximately three feet. Typically, hot cells are constructed in rows so as to share as many shielding walls as possible. A typical overall length of a row of cells might be 70 yards. A secondary mechanism exists for placing certain objects into a cell. A typical hot cell has been constructed with 8 inch diameter holes through the exterior shielded walls in the vicinity of, and usually above, the viewing windows. It became evident that if the hot cell plugs could be removed and replaced conveniently significant savings in time and personnel exposure could be realized by using these 8 inch holes as entry ports. Fifteen inch cylindrical steel plugs with a diameter of eight inches weigh about two hundred pounds. The shield plug swing mechanism comprises a steel shielding plug mounted on a retraction device that enables the plug to be pulled out of the wall and supports the weight of the pulled out plug. The retraction device is mounted on a hinge, which allows the plug to be swung out of the way so that an operator can insert material into or remove it from the interior of the hot cell and then replace the plug quickly. The hinge mounting transmits the load of the retracted plug to the concrete wall.

Knapp, P.A.; Manhart, L.K.

1994-12-31

272

Kepler constraints on planets near hot Jupiters  

SciTech Connect

We present the results of a search for planetary companions orbiting near hot Jupiter planet candidates (Jupiter-size candidates with orbital periods near 3 d) identified in the Kepler data through its sixth quarter of science operations. Special emphasis is given to companions between the 2:1 interior and exterior mean-motion resonances. A photometric transit search excludes companions with sizes ranging from roughly two-thirds to five times the size of the Earth, depending upon the noise properties of the target star. A search for dynamically induced deviations from a constant period (transit timing variations) also shows no significant signals. In contrast, comparison studies of warm Jupiters (with slightly larger orbits) and hot Neptune-size candidates do exhibit signatures of additional companions with these same tests. These differences between hot Jupiters and other planetary systems denote a distinctly different formation or dynamical history.

Steffen, Jason H.; /Fermilab; Ragozzine, Darin; /Harvard-Smithsonian Ctr. Astrophys.; Fabrycky, Daniel C.; /UC, Santa Cruz, Astron. Astrophys.; Carter, Joshua A.; /Harvard-Smithsonian Ctr. Astrophys.; Ford, Eric B.; /Florida U.; Holman, Matthew J.; /Harvard-Smithsonian Ctr. Astrophys.; Rowe, Jason F.; /NASA, Ames; Welsh, William F.; /San Diego State U., Astron. Dept.; Borucki, William J.; /NASA, Ames; Boss, Alan P.; /Carnegie Inst., Wash., D.C., DTM; Ciardi, David R.; /Caltech /Harvard-Smithsonian Ctr. Astrophys.

2012-05-01

273

Do Hot Molecular Cores Contain Massive Protostars?  

NASA Astrophysics Data System (ADS)

Hot Molecular Cores (HMCs) are hot, dense, compact clumps found in association with ultracompact HII regions and other indicators of massive star formation. They clearly have something to do with massive stars, but exactly what? One suggestion is that they contain massive protostars which heat the cores internally. Another is that they are heated externally by nearby massive stars. We plan to observe a sample at 10 and 20 (micron) to determine which of these alternatives is correct. Our observations will constrain the luminosity of HMCs and the location of hot dust; the two models make quite different predictions. If we do find evidence for protostars, we will constrain their masses and the accretion rates by comparison to the detailed models developed by Osorio & Lizano.

Mardones, Diego; Watson, Alan; Lizano, Susana; Garay, Guido; Osorio, Mayra

1999-02-01

274

MAGNETIC DRAG ON HOT JUPITER ATMOSPHERIC WINDS  

SciTech Connect

Hot Jupiters, with atmospheric temperatures T {approx}> 1000 K, have residual thermal ionization levels sufficient for the interaction of ions with the planetary magnetic field to result in a sizable magnetic drag on the (neutral) atmospheric winds. We evaluate the magnitude of magnetic drag in a representative three-dimensional atmospheric model of the hot Jupiter HD 209458b and find that it is a plausible mechanism to limit wind speeds in this class of atmospheres. Magnetic drag has a strong geometrical dependence, both meridionally and from the dayside to the nightside (in the upper atmosphere), which could have interesting consequences for the atmospheric flow pattern. By extension, close-in eccentric planets with transiently heated atmospheres will experience time-variable levels of magnetic drag. A robust treatment of magnetic drag in circulation models for hot atmospheres may require iterated solutions to the magnetic induction and Saha equations as the hydrodynamic flow is evolved.

Perna, Rosalba [JILA and Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309 (United States); Menou, Kristen; Rauscher, Emily [Department of Astronomy, Columbia University, 550 West 120th Street, New York, NY 10027 (United States)

2010-08-20

275

Baroclinic Instability on Hot Gas Giant Planets  

NASA Astrophysics Data System (ADS)

We investigate baroclinic instability under conditions applicable to hot extrasolar giant planets. Using a global general circulation model (GCM) which solves the primitive equations, we show that large-scale jets similar to those observed in current GCM simulations of hot gas giant planets are baroclinically unstable at a wide range of latitudes. For jets located at latitudes away from the equator, the growth rate and the most unstable mode are in good agreement with linear analysis. For jets located at or near the equator, the instability is strong at the jet flanks, rather than at the core. Thus, baroclinic instability is significant for understanding characteristics of hot gas giant planet atmospheres. We also demonstrate that the instability is not captured in simulations with low resolution and/or high artificial viscosity.

Polichtchouk, I.; Cho, J. Y.-K.

2011-10-01

276

Thermosphere and exosphere of hot Jupiters  

NASA Astrophysics Data System (ADS)

Here we describe the observations and the resulting constraints on the upper atmosphere (thermosphere and exosphere) of hot Jupiters. In particular, observations and theoretical modeling of hot-Jupiter evaporation are described. The observations allowed the discovery that the planet orbiting HD209458 has an extended atmosphere of escaping hydrogen and showed the presence of oxygen and carbon at very high altitude. These observations give unique constraints on the escape rate and mechanism in the atmosphere of these planets. The most recent Lyman-alpha HST observations of HD189733b allow for the first time to compare the evaporation from two different planets in different environments. We present models to quantify the escape rate from the measured occultation depths, and an energy diagram to describe the evaporation state of hot Jupiters. Using this diagram, it is shown that few already known planets could be remnants of former giant planets.

Lecavelier des Etangs, Alain

2009-02-01

277

Kepler constraints on planets near hot Jupiters.  

PubMed

We present the results of a search for planetary companions orbiting near hot Jupiter planet candidates (Jupiter-size candidates with orbital periods near 3 d) identified in the Kepler data through its sixth quarter of science operations. Special emphasis is given to companions between the 21 interior and exterior mean-motion resonances. A photometric transit search excludes companions with sizes ranging from roughly two-thirds to five times the size of the Earth, depending upon the noise properties of the target star. A search for dynamically induced deviations from a constant period (transit timing variations) also shows no significant signals. In contrast, comparison studies of warm Jupiters (with slightly larger orbits) and hot Neptune-size candidates do exhibit signatures of additional companions with these same tests. These differences between hot Jupiters and other planetary systems denote a distinctly different formation or dynamical history. PMID:22566651

Steffen, Jason H; Ragozzine, Darin; Fabrycky, Daniel C; Carter, Joshua A; Ford, Eric B; Holman, Matthew J; Rowe, Jason F; Welsh, William F; Borucki, William J; Boss, Alan P; Ciardi, David R; Quinn, Samuel N

2012-05-07

278

Hot exciton dissociation in polymer solar cells  

NASA Astrophysics Data System (ADS)

The standard picture of photovoltaic conversion in all-organic bulk heterojunction solar cells predicts that the initial excitation dissociates at the donor/acceptor interface after thermalization. Accordingly, on above-gap excitation, the excess photon energy is quickly lost by internal dissipation. Here we directly target the interfacial physics of an efficient low-bandgap polymer/PC60BM system. Exciton splitting occurs within the first 50?fs, creating both interfacial charge transfer states (CTSs) and polaron species. On high-energy excitation, higher-lying singlet states convert into hot interfacial CTSs that effectively contribute to free-polaron generation. We rationalize these findings in terms of a higher degree of delocalization of the hot CTSs with respect to the relaxed ones, which enhances the probability of charge dissociation in the first 200?fs. Thus, the hot CTS dissociation produces an overall increase in the charge generation yield.

Grancini, G.; Maiuri, M.; Fazzi, D.; Petrozza, A.; Egelhaaf, H.-J.; Brida, D.; Cerullo, G.; Lanzani, G.

2013-01-01

279

The time-limited hot line.  

PubMed

Although long-term hot lines that focus on crisis intervention will undoubtedly dominate as an organizational model, time-limited approaches will be used with increasing frequency. The primary impetus behind their proliferation is the increasing visibility of the electronic media, particularly television, in investigating and reporting pressing health, mental health, and human services problems. As the mass media increasingly produces special reports, documentaries, and docudramas directed toward social problems and issues, local health and human services agencies will become increasingly motivated to provide a forum for public response. The time-limited issue- or problem-oriented hot line is the ideal vehicle for public response as well as for extending the human services network. This type of hot line also offers social workers a unique opportunity to share important mental health information through the media. PMID:8511660

Loring, M T; Wimberley, E T

1993-05-01

280

Hot gas filter and system assembly  

DOEpatents

A filter element for separating fine dirty particles from a hot gas. The filter element comprises a first porous wall and a second porous wall. Each porous wall has an outer surface and an inner surface. The first and second porous walls being coupled together thereby forming a substantially closed figure and open at one end. The open end is formed to be coupled to a hot gas clean up system support structure. The first and second porous walls define a channel beginning at the open end and terminate at the closed end through which a filtered clean gas can flow through and out into the clean gas side of a hot gas clean up system.

Lippert, Thomas Edwin (Murrysville, PA); Palmer, Kathryn Miles (Monroeville, PA); Bruck, Gerald Joseph (Murrysville, PA); Alvin, Mary Anne (Pittsburgh, PA); Smeltzer, Eugene E. (Export, PA); Bachovchin, Dennis Michael (Murrysville, PA)

1999-01-01

281

Radioactive hot cell access hole decontamination machine  

DOEpatents

Radioactive hot cell access hole decontamination machine. A mobile housing has an opening large enough to encircle the access hole and has a shielding door, with a door opening and closing mechanism, for uncovering and covering the opening. The housing contains a shaft which has an apparatus for rotating the shaft and a device for independently translating the shaft from the housing through the opening and access hole into the hot cell chamber. A properly sized cylindrical pig containing wire brushes and cloth or other disks, with an arrangement for releasably attaching it to the end of the shaft, circumferentially cleans the access hole wall of radioactive contamination and thereafter detaches from the shaft to fall into the hot cell chamber.

Simpson, William E. (Richland, WA)

1982-01-01

282

Multi-cylinder hot gas engine  

DOEpatents

A multi-cylinder hot gas engine having an equal angle, V-shaped engine block in which two banks of parallel, equal length, equally sized cylinders are formed together with annular regenerator/cooler units surrounding each cylinder, and wherein the pistons are connected to a single crankshaft. The hot gas engine further includes an annular heater head disposed around a central circular combustor volume having a new balanced-flow hot-working-fluid manifold assembly that provides optimum balanced flow of the working fluid through the heater head working fluid passageways which are connected between each of the cylinders and their respective associated annular regenerator units. This balanced flow provides even heater head temperatures and, therefore, maximum average working fluid temperature for best operating efficiency with the use of a single crankshaft V-shaped engine block.

Corey, John A. (North Troy, NY)

1985-01-01

283

Efficient heating and domestic hot water apparatus  

SciTech Connect

An efficient, compact boiler system providing both heating water for heating an enclosed space, such as a home, and domestic hot water for washing and similar purposes, has a limited fluid capacity primary heating coil within a combustion chamber. The coil supplies heated water to a larger capacity storage boiler located directly below the primary boiler and connected to it by header pipes which themselves form a manifold into which the primary coil is connected. The storage boiler distributes the heated water through the heating system. An elongated secondary heating coil within the boiler heats the domestic hot water supply by heat transfer from the boiler water. The return header pipe discharges heated water directly into the interior loop of the secondary coil to quickly heat the domestic hot water when the burner is ''on''.

Gerstmann, J.; Pompei, F.

1980-09-16

284

Degenerate stars. XII - Recognition of hot nondegenerates  

NASA Astrophysics Data System (ADS)

Fifty-one newly observed degenerate stars and 14 nondegenerates include 13 faint red stars, most of which do not show any lines except DF, Gr 554. Hot subdwarfs and an X-ray source are discussed along with the problem of low-resolution spectroscopic classification of dense hot stars. The multichannel spectrum of the carbon-rich magnetic star LP 790-29 is examined by fitting the undisturbed parts of the spectrum to a black body of 7625 K by the least squares method; the Swan bands absorb 600 A of the spectrum assuming that the blocked radiation is redistributed in the observed region.

Greenstein, J. L.

1980-12-01

285

Generalised Einstein relation for hot Brownian motion  

NASA Astrophysics Data System (ADS)

The Brownian motion of a hot nanoparticle is described by an effective Markov theory based on fluctuating hydrodynamics. Its predictions are scrutinized over a wide temperature range using large-scale molecular dynamics simulations of a hot nanoparticle in a Lennard-Jones fluid. The particle positions and momenta are found to be Boltzmann distributed according to distinct effective temperatures THBM and Tk. For THBM we derive a formally exact theoretical prediction and establish a generalised Einstein relation that links it to directly measurable quantities.

Chakraborty, D.; Gnann, M. V.; Rings, D.; Glaser, J.; Otto, F.; Cichos, F.; Kroy, K.

2011-12-01

286

Method for hot pressing beryllium oxide articles  

DOEpatents

The hot pressing of beryllium oxide powder into high density compacts with little or no density gradients is achieved by employing a homogeneous blend of beryllium oxide powder with a lithium oxide sintering agent. The lithium oxide sintering agent is uniformly dispersed throughout the beryllium oxide powder by mixing lithium hydroxide in an aqueous solution with beryllium oxide powder. The lithium hydroxide is converted in situ to lithium carbonate by contacting or flooding the beryllium oxide - lithium hydroxide blend with a stream of carbon dioxide. The lithium carbonate is converted to lithium oxide while remaining fixed to the beryllium oxide particles during the hot pressing step to assure uniform density throughout the compact.

Ballard, A.H.; Godfrey, T.G. Jr.; Mowery, E.H.

1986-10-10

287

New hot subdwarf stars (Oreiro+, 2011)  

NASA Astrophysics Data System (ADS)

Making use of VO tools we thoroughly search stellar catalogues to retrieve multi-colour photometry and astrometric information of a known sample of blue objects, including hot subdwarfs, white dwarfs, cataclysmic variables and main-sequence OB stars. We define a procedure to distinguish among these spectral classes, which is particularly designed to obtain a hot subdwarf sample with a low contamination factor. To check the validity of the method, this procedure is then applied to two test sky regions: to the Kepler FoV and to a test region of 300deg2 around (RA:225°, DE:5°). (2 data files).

Oreiro, R.; Rodriguez-Lopez, C.; Solano, E.; Ulla, A.; Ostensen, R.; Garcia-Torres, M.

2011-08-01

288

Hot dry rock venture risks investigation:  

SciTech Connect

This study assesses a promising resource in central Utah as the potential site of a future commerical hot dry rock (HDR) facility for generating electricity. The results indicate that, if the HDR reservoir productivity equals expectations based on preliminary results from research projects to date, a 50 MWe HDR power facility at Roosevelt Hot Springs could generate power at cost competitive with coal-fired plants. However, it is imperative that the assumed productivity be demonstrated before funds are committed for a commercial facility. 72 refs., 39 figs., 38 tabs.

Not Available

1988-01-01

289

Validation of the Hot Strip Mill Model  

SciTech Connect

The Hot Strip Mill Model (HSMM) is an off-line, PC based software originally developed by the University of British Columbia (UBC) and the National Institute of Standards and Technology (NIST) under the AISI/DOE Advanced Process Control Program. The HSMM was developed to predict the temperatures, deformations, microstructure evolution and mechanical properties of steel strip or plate rolled in a hot mill. INTEG process group inc. undertook the current task of enhancing and validating the technology. With the support of 5 North American steel producers, INTEG process group tested and validated the model using actual operating data from the steel plants and enhanced the model to improve prediction results.

Richard Shulkosky; David Rosberg; Jerrud Chapman

2005-03-30

290

Cooling of hot electrons in amorphous silicon  

SciTech Connect

Measurements of the cooling rate of hot carriers in amorphous silicon are made with a two-pump, one-probe technique. The experiment is simulated with a rate-equation model describing the energy transfer between a population of hot carriers and the lattice. An energy transfer rate proportional to the temperature difference is found to be consistent with the experimental data while an energy transfer independent of the temperature difference is not. This contrasts with the situation in crystalline silicon. The measured cooling rates are sufficient to explain the difficulty in observing avalanche effects in amorphous silicon.

Vanderhaghen, R.; Hulin, D.; Cuzeau, S.; White, J.O.

1997-07-01

291

Glowing Hot Transiting Exoplanet Discovered  

NASA Astrophysics Data System (ADS)

VLT Spectra Indicate Shortest-Known-Period Planet Orbiting OGLE-TR-3 Summary More than 100 exoplanets in orbit around stars other than the Sun have been found so far. But while their orbital periods and distances from their central stars are well known, their true masses cannot be determined with certainty, only lower limits. This fundamental limitation is inherent in the common observational method to discover exoplanets - the measurements of small and regular changes in the central star's velocity, caused by the planet's gravitational pull as it orbits the star. However, in two cases so far, it has been found that the exoplanet's orbit happens to be positioned in such a way that the planet moves in front of the stellar disk, as seen from the Earth. This "transit" event causes a small and temporary dip in the star's brightness, as the planet covers a small part of its surface, which can be observed. The additional knowledge of the spatial orientation of the planetary orbit then permits a direct determination of the planet's true mass. Now, a group of German astronomers [1] have found a third star in which a planet, somewhat larger than Jupiter, but only half as massive, moves in front of the central star every 28.5 hours . The crucial observation of this solar-type star, designated OGLE-TR-3 [2] was made with the high-dispersion UVES spectrograph on the Very Large Telescope (VLT) at the ESO Paranal Observatory (Chile). It is the exoplanet with the shortest period found so far and it is very close to the star, only 3.5 million km away. The hemisphere that faces the star must be extremely hot, about 2000 °C and the planet is obviously losing its atmosphere at high rate . PR Photo 10a/03 : The star OGLE-TR-3 . PR Photo 10b/03 : VLT UVES spectrum of OGLE-TR-3. PR Photo 10c/03 : Relation between stellar brightness and velocity (diagram). PR Photo 10d/03 : Observed velocity variation of OGLE-TR-3. PR Photo 10e/03 : Observed brightness variation of OGLE-TR-3. The search for exoplanets More than 100 planets in orbit around stars other than the Sun have been found so far. These "exoplanets" come in many different sizes and they move in a great variety of orbits at different distances from their central star, some nearly round and others quite elongated. Some planets are five to ten times more massive than the largest one in the solar system, Jupiter - the lightest exoplanets known at this moment are about half as massive as Saturn, i.e. about 50 times more massive than the Earth. Astronomers are hunting exoplanets not just to discover more such objects, but also to learn more about the apparent diversity of planetary systems. The current main research goal is to eventually discover an Earth-like exoplanet, but the available telescopes and instrumentation are still not "sensitive" enough for this daunting task. However, also in this context, it is highly desirable to know not only the orbits of the observable exoplanets, but also their true masses . But this is not an easy task. Masses of exoplanets Virtually all exoplanets detected so far have been found by an indirect method - the measurement of stellar velocity variations . It is based on the gravitational pull of the orbiting planet that causes the central star to move a little back and forth; the heavier the planet, the greater is the associated change in the star's velocity. This technique is rapidly improving: the new HARPS spectrograph (High Accuracy Radial Velocity Planet Searcher) , now being tested on the 3.6-m telescope at the ESO La Silla Observatory , can measure such stellar motions with an unrivalled accuracy of about 1 metre per second (m/s), cf. ESO PR 06/03 . It will shortly be able to search for exoplanets only a few times more massive than the Earth. However, velocity measurements alone do not allow to determine the true mass of the orbiting planet. Because of the unknown inclination of the planetary orbit (to the line-of-sight), they only provide a lower limit to this mass . Additional information about this orbital inclination

2003-04-01

292

Kiln for hot-pressing compacts in a continuous manner  

DOEpatents

The invention is directed to a hot pressing furnace or kiln which is capable of preheating, hot pressing, and cooling a plurality of articles in a sequential and continuous manner. The hot pressing furnace of the present invention comprises an elongated, horizontally disposed furnace capable of holding a plurality of displaceable pusher plates each supporting a die body loaded with refractory or ceramic material to be hot pressed. Each of these plates and the die body supported thereby is sequentially pushed through the preheating zone, a temperature stabilizing and a hot pressing zone, and a cooling zone so as to provide a continuous hot-pressing operation of a plurality of articles.

Reynolds, C.D Jr.

1983-08-08

293

Kiln for hot-pressing compacts in a continuous manner  

DOEpatents

The present invention is directed to a hot pressing furnace or kiln which is capable of preheating, hot pressing, and cooling a plurality of articles in a sequential and continuous manner. The hot pressing furnace of the present invention comprises an elongated, horizontally disposed furnace capable of holding a plurality of displaceable pusher plates each supporting a die body loaded with refractory or ceramic material to be hot pressed. Each of these plates and the die body supported thereby is sequentially pushed through the preheating zone, a temperature stabilizing and a hot pressing zone, and a cooling zone so as to provide a continuous hot-pressing operation of a plurality of articles.

Reynolds, Jr., Carl D. (Clinton, TN)

1985-01-01

294

Amplification of Hot DNA segments in Escherichia coli.  

PubMed

In Escherichia coli, a replication fork blocking event at a DNA replication terminus (Ter) enhances homologous recombination at the nearby sister chromosomal region, converting the region into a recombination hotspot, Hot, site. Using a RNaseH negative (rnhA-) mutant, we identified eight kinds of Hot DNAs (HotA-H). Among these, enhanced recombination of three kinds of Hot DNAs (HotA-C) was dependent on fork blocking events at Ter sites. In the present study, we examined whether HotA DNAs are amplified when circular DNA (HotA plus a drug-resistance DNA) is inserted into the homologous region on the chromosome of a rnhA- mutant. The resulting HotA DNA transformants were analysed using pulsed-field gel electrophoresis, fluorescence in situ hybridization and DNA microarray technique. The following results were obtained: (i) HotA DNA is amplified by about 40-fold on average; (ii) whereas 90% of the cells contain about 6-10 copies of HotA DNA, the remaining 10% of cells have as many as several hundred HotA copies; and (iii) amplification is detected in all other Hot DNAs, among which HotB and HotG DNAs are amplified to the same level as HotA. Furthermore, HotL DNA, which is activated by blocking the clockwise oriC-starting replication fork at the artificially inserted TerL site in the fork-blocked strain with a rnhA+ background, is also amplified, but is not amplified in the non-blocked strain. From these data, we propose a model that can explain production of three distinct forms of Hot DNA molecules by the following three recombination pathways: (i) unequal intersister recombination; (ii) intrasister recombination, followed by rolling-circle replication; and (iii) intrasister recombination, producing circular DNA molecules. PMID:12354226

Kodama, Ken-Ichi; Kobayashi, Takehiko; Niki, Hironori; Hiraga, Sota; Oshima, Taku; Mori, Hirotada; Horiuchi, Takashi

2002-09-01

295

Hot Water Storage Tank for Solar Collectors.  

National Technical Information Service (NTIS)

A baffled hot storage tank for solar collector systems is provided. The tank includes a concentric of the baffle and another circulation part at the top of the baffle. This configuration restricts the mixing of water allowing both a vertical temperature g...

J. S. Roehl

1992-01-01

296

Radiation from hot, bare, strange stars  

Microsoft Academic Search

We present the results of numerical simulations of stationary, spherically outflowing, e+\\/- pair winds, with total luminosities of L= 1035-1042 erg s-1. These results have direct relevance to the emission from hot, bare, strange stars, which are thought to be powerful sources of pairs created by the Coulomb barrier at the quark surface. The spectra of emergent photons and pairs

A. G. Aksenov; M. Milgrom; V. V. Usov

2003-01-01

297

The Hot Big Bang:. Physics and Cosmology  

Microsoft Academic Search

The discovery of the cosmic microwave background 36 years ago established the Hot Big Bang model, and demonstrated convincingly that early epochs in the history of the Universe were very different from the present. Studies of the cosmic microwave background (CMB) have also turned cosmology into a real physical science: CMB measurements can be used to shed light on areas

R. B. Partridge

2002-01-01

298

Hot pair-dominated accretion disks  

Microsoft Academic Search

The structure and properties of geometrically thin steady hot two-temperature accretion disks, where Comptonized bremsstrahlung is the dominant emission mechanism, are analyzed using a new method based on the fact that the disk solutions depend on two parameters only. The method allows all possible local disk solutions to be displayed as a surface in a single figure. Local disk solutions

Gunnlaugur Bjornsson; Roland Svensson

1992-01-01

299

Facilities Bonds Prove Hot Item under Stimulus  

ERIC Educational Resources Information Center

Construction bonding authority--a technical, and often obscure, source of capital funding for school districts--has emerged as a hot ticket for those looking to finance school facilities work under the federal government's economic-stimulus program. School districts left out of the loop for direct funding are lining up for some of at least $24…

Klein, Alyson

2009-01-01

300

Icing Tunnel Test - Hot-Film Anemometer.  

National Technical Information Service (NTIS)

A limited test is reported of a Thermo-Systems Inc Series 1050 constant-temperature hot-film anemometer system in the Lockheed-California Company icing research tunnel to determine its suitability as a detector of discrete water droplets and liquid water ...

P. R. Bonin R. P. Jefferis

1974-01-01

301

Hot embossing for micropatterned cell substrates  

Microsoft Academic Search

This paper reports the development of a technique for preparing microtextured polymer substrates for cell growth and studies the response of osteoblast cells grown on these surfaces. The surfaces were manufactured with hot embossing, where a silicon micromachined printing master was pressed into a thermoplastic polymer substrate at elevated temperature, forming a regular microgroove pattern in the polymer. The grooves

Joseph L. Charest; Lindsay E. Bryant; Andres J. Garcia; William P. King

2004-01-01

302

Micro Hot Embossing for Replication of Microstructures  

Microsoft Academic Search

This paper reports the development of a micro-hot embossing process for high-quality microstructure transfer from molds to polymer materials. Polycarbonate was selected as the structural material. Replications of rectangular reflecting mirrors with dimensions of 500 mum (L) × 100 mum (W) × 220 mum (H) were performed. To replicate such microstructures with vertical sidewall surfaces, a combination of temperature of

Xue Chuan Shan; Ryutaro Maeda; Yoichi Murakoshi

2003-01-01

303

Rapid hot embossing of polymer microfeatures  

Microsoft Academic Search

Although the hot embossing process is gaining popularity in molding polymer micro\\/nano structures, it needs a breakthrough improvement in reducing cycle time before it can become a mass-production process. In this study, an embossing tool with a rapid heating and cooling capability was investigated to reduce the cycle time. During the process, the embossing tool was rapidly heated to above

Thomas E. Kimerling; Weidan Liu; Byung H. Kim; Donggang Yao

2006-01-01

304

Microlens array produced using hot embossing process  

Microsoft Academic Search

In this paper, the fabrication of molds that are suitable for the production of microlens arrays using the replication technique is discussed. Variation of parameters in the replication process were investigated. A focused ion beam was used to fabricate the microlens cavities on three materials, with silicon showing the best result. Hot embossing was used to produce replicated polycarbonate lens

N. S Ong; Y. H Koh; Y. Q Fu

2002-01-01

305

Portfolio Capital Flows: Hot or Cold  

Microsoft Academic Search

A distinction is often made between short-term and long-term capital flows: the former are deemed unstable hot money and the latter are deemed stable cold money. Using time-series analysis of balance of payments data for five industrial and five developing countries, we find that in most cases the labels \\

Stijn Claessens; Michael P. Dooley; Andrew Warner

1995-01-01

306

Hot water can freeze faster than cold?!?  

Microsoft Academic Search

We review the Mpemba effect, where intially hot water freezes faster than initially cold water. While the effect appears impossible at first sight, it has been seen in numerous experiments, was reported on by Aristotle, Francis Bacon, and Descartes, and has been well-known as folklore around the world. It has a rich and fascinating history, which culminates in the dramatic

Monwhea Jeng

2005-01-01

307

When hot water freezes before cold  

Microsoft Academic Search

I suggest that the origin of the Mpemba effect (the freezing of hot water before cold) is due to freezing-point depression by solutes, either gaseous or solid, whose solubility decreases with increasing temperature so that they are removed when water is heated. The solutes are concentrated ahead of the freezing front by zone refining in water that has not been

J. I. Katz

2009-01-01

308

Hot spot mutations in adenosine deaminase deficiency  

SciTech Connect

The authors have previously characterized mutant adenosine deaminase enzymes in seven children with partial ADA deficiency. Six children shared common origins, suggesting a common progenitor. However, they found evidence for multiple phenotypically different mutant enzymes. They hypothesized that many of the mutations would be at CpG dinucleotides, hot spots at which spontaneous deamination of 5-methylcytosine results in C to T or G to A transitions. Digestion of DNA from these children with Msp I and Taq I, enzymes recognizing CpG dinucleotides, identified three different mutations, each correlating with expression of a different mutant enzyme. Sequencing of cDNA clones and genomic DNA amplified by polymerase chain reaction confirmed the presence of C to T or G to A transitions at CpG dinucleotides. To determine the true frequency of hot spot mutation in these children, consecutively ascertained through a newborn screening program, they sequenced cDNA from the remaining alleles. Two others were hot spot mutations each again resulting in expression of a phenotypically different mutant enzyme. These seven mutations account for all 14 chromosomes in these children. There is thus a very high frequency of hot spot mutations in partial ADA deficiency. They were able to correlate genotype and phenotype and to dissect the activity of individual mutant alleles.

Hirschhorn, R.; Tzall, S.; Ellenbogen, A. (New York Univ. Medical School, NY (USA))

1990-08-01

309

Hot Dry Rock Overview at Los Alamos  

Microsoft Academic Search

The Hot Dry Rock (HDR) geothermal energy program is a renewable energy program that can contribute significantly to the nation's balanced and diversified energy mix. Having extracted energy from the first Fenton Hill HDR reservoir for about 400 days, and from the second reservoir for 30 days in a preliminary test, Los Alamos is focusing on the Long Term Flow

Michael Berger; Robert H. Hendron

1989-01-01

310

HOT PRESSING OF POTASSIUM-SODIUM NIOBATES  

Microsoft Academic Search

Compositions in the system KNbOâ--NaNbOâ were hotpressed to ; yield ceramics with relative densities greater than 99%. Because these materials ; lack any degree of pyroplastic behavior, temperatures approaching those required ; for air sintering are needed. These hot-pressed specimens exhibit a finer ; microstructure than that obtainable by conventional processing. Enhanced ; piezoelectric coefficients are observed, and in certain

R. E. Jaeger; L. Egerton

1962-01-01

311

Facilities Bonds Prove Hot Item under Stimulus  

ERIC Educational Resources Information Center

|Construction bonding authority--a technical, and often obscure, source of capital funding for school districts--has emerged as a hot ticket for those looking to finance school facilities work under the federal government's economic-stimulus program. School districts left out of the loop for direct funding are lining up for some of at least $24…

Klein, Alyson

2009-01-01

312

Hot topics in flavor physics at CDF  

SciTech Connect

Hot topics in flavor physics at CDF are reviewed. Selected results of top, beauty, charm physics and exotic states in about 200 pb{sup -1} data collected by the CDF II detector in p{bar p} collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron are presented.

Jun, Soon Yung; /Carnegie Mellon U.

2005-01-01

313

Robust Steering Control of Hot Strip Mill  

Microsoft Academic Search

In this paper, a robust steering control is proposed as a means to guarantee the stability of a hot strip finishing mill and improve its performances. The aim of the rolling process is to obtain a metal strip which is uniform and at the desired thickness. The lateral movement of the strip may reduce the quality of the product and

Ivan Malloci; Jamal Daafouz; Claude Iung; Rémi Bonidal; Patrick Szczepanski

2010-01-01

314

Linear constraints in hot clutter cancellation  

Microsoft Academic Search

This paper addresses the use of adaptive array signal processing in airborne radar systems to remove terrain-scattered interference, or hot clutter. Mitigation of terrain scattered interference in airborne radar systems involves cancellation of reflections from a multiplicity of ground reflector locations each having potentially different directions of arrival, time delay, and Doppler. This paper presents a specific methodology for the

Lloyd J. Griffiths

1996-01-01

315

Time to B. cereus about hot chocolate.  

PubMed Central

OBJECTIVE: To determine the cause of illnesses experienced by employees of a Minneapolis manufacturing plant after drinking hot chocolate bought from a vending machine and to explore the prevalence of similar vending machine-related illnesses. METHODS: The authors inspected the vending machines at the manufacturing plant where employees reported illnesses and at other locations in the city where hot chocolate beverages were sold in machines. Tests were performed on dry mix, water, and beverage samples and on machine parts. RESULTS: Laboratory analyses confirmed the presence of B. cereus in dispensed beverages at a concentration capable of causing illness (170,000 count/gm). In citywide testing of vending machines dispensing hot chocolate, 7 of the 39 licensed machines were found to be contaminated, with two contaminated machines having B. cereus levels capable of causing illness. CONCLUSIONS: Hot chocolate sold in vending machines may contain organisms capable of producing toxins that under favorable conditions, can induce illness. Such illnesses are likely to be underreported. Even low concentrations of B. cereus may be dangerous for vulnerable populations such as the aged or immunosuppressed. Periodic testing of vending machines is thus warranted. The relationship between cleaning practices and B. cereus contamination is an issue for further study.

Nelms, P K; Larson, O; Barnes-Josiah, D

1997-01-01

316

Nontuberculous mycobacterial disease following hot tub exposure.  

PubMed Central

Nontuberculous mycobacteria (NTM) have been recognized as an important cause of disease in immunocompromised hosts. Pulmonary disease caused by NTM is increasingly recognized in previously healthy persons. Investigation of pulmonary disease affecting a family of five identified an indoor hot tub as the source of NTM-related disease.

Mangione, E. J.; Huitt, G.; Lenaway, D.; Beebe, J.; Bailey, A.; Figoski, M.; Rau, M. P.; Albrecht, K. D.; Yakrus, M. A.

2001-01-01

317

Microbial Ecology of Olympic Hot Springs  

Microsoft Academic Search

Thg ecglggy of Olympic Hor Springs in Olympic National Park was studied through laboratory and field_observarions The hot spring environment provided an interesting system for study since it probably had existed throughout the time that life had been evolving on earh. The otganisms found growing under these thermal conditions helped to reveal the extent to which evolutioo had been pushed.

John G. Kleyn

318

Hot-dry-rock geothermal resource 1980  

SciTech Connect

The work performed on hot dry rock (HDR) geothermal resource evaluation, site characterization, and geophysical exploration techniques is summarized. The work was done by region (Far West, Pacific Northwest, Southwest, Rocky Mountain States, Midcontinent, and Eastern) and limited to the conterminous US.

Heiken, G.; Goff, F.; Cremer, G. (ed.)

1982-04-01

319

Tribological behaviour of hot rolling rolls  

Microsoft Academic Search

The study of wear mechanisms represents a very important task for the development of roll materials, with improved hot tribological properties. In the present paper the wear behaviour of different materials, i.e., high alloy steels (high speed steels (HSS)) and cast irons (high chromium irons (HiCr) and indefinite chill irons (IC)), produced by centrifugal casting, has been comparatively evaluated by

M. Pellizzari; A. Molinari; G. Straffelini

2005-01-01

320

Mathematical modeling of deformation during hot rolling.  

National Technical Information Service (NTIS)

The deformation that occurs in the roll bite during the hot rolling of steel, particularly the strain-rate and strain distribution, has been mathematically modeled using finite-element analysis. In this paper three different finite-element models are comp...

D. Jin R. G. Stachowiak I. V. Samarasekera J. K. Brimacombe

1994-01-01

321

Roll Lubrication in Hot Rolling Processes.  

National Technical Information Service (NTIS)

Following a discussion on the possible benefits and mechanisms of work roll lubrication in the hot rolling process, the report describes its initial development on a wide strip mill. The design and testing of a second-generation system is presented in whi...

F. J. Westlake C. L. Robinson C. Webb

1973-01-01

322

Damage in hot rolling work rolls  

Microsoft Academic Search

Samples from a couple of work rolls employed in a hot rolling steel strip mill were examined by scanning electron microscopy in order to study their surface, as well as the wear mechanisms responsible for their damage. It was found that a series of cracks develop within the rolls at the beginning of their operational cycle, these cracks follow the

Rafael Colás; Jorge Ram??rez; Ignacio Sandoval; Julio C Morales; Luis A Leduc

1999-01-01

323

Surface analytical studies of hot rolled aluminum  

SciTech Connect

Studies of the oxide films on ingot and hot rolled aluminum surfaces show that mean oxide film thickness on a commercial purity (99.5%) metal surface is reduced considerably as a result of rolling on the breakdown mill of a conventional hot rolling line. Further reduction in oxide film thickness occurs during the subsequent passage of the metal through the three-stand tandem mill on the same line. During rolling, fatty acid loading bearing additives chemisorb on to the rolled metal surface. Rolling operations also result in progressive decreases in the levels of trace elements remaining on the surface. Surface hydroxide levels may also depend on the conditions used for the hot rolling operation. Defects formed in hot mill roll coatings on a small experimental mill do not penetrate to the steel substrate but they may result in aluminum oxides being found deep into the rolled aluminum substrate. Defect areas on the roll surface are covered with a layer comprised of a mixture of aluminum metal and oxide which is of higher metal content than the surrounding coating.

Treverton, J.A.; Ball, J. [Alcan International, Oxon (United Kingdom)

1994-05-01

324

Integrated Approach for Prediction of Hot Tearing  

NASA Astrophysics Data System (ADS)

Shrinkage, imposed strain rate, and (lack of) feeding are considered the main factors that determine cavity formation or the formation of hot tears. A hot-tearing model is proposed that will combine a macroscopic description of the casting process and a microscopic model. The micromodel predicts whether porosity will form or a hot tear will develop. Results for an Al-4.5 pct Cu alloy are presented as a function of the constant strain rate and cooling rate. Also, incorporation of the model in a finite element method (FEM) simulation of the direct-chill (DC) casting process is reported. The model shows features well known from literature such as increasing hot-tearing sensitivity with increasing deformation rate, cooling rate, and grain size. Similar trends are found for the porosity formation as well. The model also predicts a beneficial effect of applying a ramping procedure during the start-up phase, which is an improvement in comparison with earlier findings obtained with alternative models. In principle, the model does not contain adjustable parameters, but several parameters are not well known. A full quantitative validation not only requires detailed casting trials but also independent determination of some thermophysical parameters of the semisolid mush.

Suyitno; Kool, W. H.; Katgerman, L.

2009-10-01

325

Flow stress prediction at hot working conditions  

Microsoft Academic Search

The hot flow stress of 17-4 PH stainless steel was modeled using the constitutive equations. The hyperbolic sine equation with strain dependent constants for compensation of strain was found to be inappropriate for flow stress modeling and prediction. A new formula has been developed for the prediction of DRX flow curve in a simple form with the peak stress, peak

H. Mirzadeh; A. Najafizadeh

2010-01-01

326

ESCITALOPRAM TREATMENT OF MENOPAUSAL HOT FLASHES  

PubMed Central

Objective To determine the effects of 10 mg and 20 mg/day of escitalopram on objectively-recorded hot flashes and on the rectal temperature threshold for sweating. Method Two studies were performed: 16 women received 10 mg/day and 26 women received 20 mg/day escitalopram for eight weeks. They were randomly assigned in equal numbers to receive active drug or placebo in double-blind fashion. Hot flash frequency was measured with an ambulatory recorder during the first three weeks and during the eighth week of the study. The rectal temperature threshold for sweating was measured during the first and eighth weeks of the study using published methods. Results In the first study, there were no significant effects whatsoever for any measure. In the second study, the escitalopram group showed an average decline in hot flash frequency of 14.4%, whereas, the placebo group showed an average increase of 6.7% (P < .05). However, there were no significant effects across time for either group. There were no significant effects whatsoever for rectal temperature sweating thresholds. Conclusions Escitalopram at 10 mg or 20 mg/day is not effective in the treatment of menopausal hot flashes.

Freedman, Robert R.; Kruger, Michael L.; Tancer, Manuel E.

2011-01-01

327

The Flying Hot Wire and Related Instrumentation.  

National Technical Information Service (NTIS)

A flying hot-wire technique is proposed for studies of separated turbulent flow in wind tunnels. The technique avoids the problem of signal rectification in regions of high turbulence level by moving the probe rapidly through the flow on the end of a rota...

D. Coles B. Cantnell A. Wadcock

1978-01-01

328

Hot Wall Thickness Variation Measurement System.  

National Technical Information Service (NTIS)

With the introduction of the rotary forge at the Watervliet Arsenal, a new line of inspection equipment was required. The need to design inspection equipment to measure hot cannon tubes in the 'as forged' condition created gaging problems not often encoun...

S. J. Krupski

1979-01-01

329

Hot Working of Titanium and Titanium Alloys.  

National Technical Information Service (NTIS)

In the patent application alpha titanium or an alpha-plus-beta titanium alloy is heated in a hydrogen atmosphere under conditions such as to convert it to beta titanium or a beta titanium alloy which is then hot worked to provide an article of a desired s...

V. DePierre

1976-01-01

330

Hot rolling simulations of austenitic stainless steel  

Microsoft Academic Search

The dynamic, static and metadynamic recrystallization behavior of austenitic stainless steel during hot rolling was analyzed. In this approach, each of those recrystallization behaviors is described by appropriate kinetics equations. The critical strain for dynamic recrystallization was determined so that a distinction could be made between static and metadynamic recrystallization; then the amounts of strain accumulation compared with the critical

Sang-Hyun Cho; Yeon-Chul Yoo

2001-01-01

331

Hot spot histories in energetic materials  

Microsoft Academic Search

Interest in the mechanisms by which hot spots either grow to sustained reaction or are quenched results from the observation that the energy required to ignite a propellant or explosive can be significantly less than that needed to bulk heat a test specimen uniformly to its ignition temperature. This result is independent of the original form of nonthermal energy and

A. M. Mellor; D. A. Wiegand; K. B. Isom

1995-01-01

332

Hot-Melt Extrusion Technique: A Review  

Microsoft Academic Search

Hot-melt extrusion is one of the most widely applied processing technologies in the plastic, rubber and food industry. Today this technology has found its place in the array of pharmaceutical manufacturing operations. Melt extrusion process are currently applied in the pharmaceutical field for the manufacture of a variety of dosage forms and formulations such as granules, pellets, tablets, suppositories, implants,

Rina Chokshi; Hossein Zia

333

Hot corrosion of materials: Fundamental studies  

NASA Astrophysics Data System (ADS)

Hot corrosion is the accelerated oxidation of materials at elevated temperatures induced by a thin film of fused salt deposit. Because of its high thermodynamic stability in the mutual presence of sodium and sulfur impurities in an oxidizing gas, Na2SO4 is often found to be the dominant salt in the deposit. The corrosive oxyanion-fused salts are usually ionically conducting electrolytes that exhibit an acid/base chemistry, so that hot corrosion must occur by an electrochemical mechanism that may involve fluxing of the protective oxides. With the aid of high-temperature reference electrodes to quantify an acid/base scale, the solubilities for various metal oxides in fused Na2SO4 have been measured, and these show remarkable agreement with the theoretical expectations from the thermodynamic phase stability diagrams for the relevant Na-Metal-S-O systems. The solubilities of several oxides infused Na2SO4-NaVO3 salt solutions have also been measured and modeled. Such information is important both in evaluating the corrosion resistance of materials and in interpreting any oxide fluxing/reprecipitation mechanisms. Various electrochemical measurements have identified the S2O7 2- anion (dissolved SO3) as the oxidant that is reduced in the hot corrosion process. Electrochemical polarization studies have elucidated the corrosion reactions and clarified the corrosion kinetics of alloys. Mechanistic models for Type I and Type II hot corrosion are discussed briefly.

Rapp, Robert A.; Zhang, Yun-Shu

1994-12-01

334

Hot-embossed polymeric optical waveguides  

Microsoft Academic Search

Polymer waveguides have attracted a great deal of attention for their potential applications as optical components in optical communications, optical interconnections and optical sensors because they are easy to manufacture at a low temperature, and they have a low processing cost. Hot embossing is powerful and effective tools to produce a large volume of waveguides and structure high-precision micro\\/nano patterns

Choon-Gi Choi; Jin-Tae Kim; Sang-Pil Han; Seung-Ho Ahn

2004-01-01

335

New thermostable steels for hot dies  

Microsoft Academic Search

The life of die equipment is an important aspect of the efficiency of hot stamping. The die life may be increased, in particular, by using steels with specified physical and mechanical properties at high temperatures. The development of new steels and determination of optimal heat-treatment conditions must be based on analysis of the operating conditions of the tool and determination

E. I. Ponkratin; D. V. Lenartovich; A. B. Steblov

2009-01-01

336

Modeling of the Hot Isostatic Pressing Process.  

National Technical Information Service (NTIS)

This report describes the first year of progress of a two year investigation to develop a modeling strategy to predict the final shape of components manufactured by the Hot Isostatic Pressing (HIP) process. When a powder metal is subjected to the high pre...

B. N. Cassenti K. J. Cheverton

1979-01-01

337

Fastener tightening in a radioactive (hot) cell  

Microsoft Academic Search

Accurate remote tightening of fasteners in a radioactive (Hot) cell can be a very exasperating experience. Viewing can be difficult (in many places) and work sometimes must be done using mirrors and\\/or cameras. If electro mechanical manipulators are used, the operator has no ''feel,'' which often can result in cross threading, or improper torquing of fasteners. At the Interim Examination

Kalk

1986-01-01

338

Solar hot water system without heat exchanger  

Microsoft Academic Search

A solar collector is connected to a storage tank. A thermo-siphon heater is connected to the storage tank. A pressurized tank is connected to the upper portion of the storage tank. A vertically moveable insulated divider floats in the storage tank to separate hot and cold water in the storage tank. Means are provided to withdraw water from storage and

1985-01-01

339

Progress in hot dry rock technology development  

Microsoft Academic Search

The hot dry rock (HDR) geothermal energy program at Los Alamos is directed toward demonstrating the viability of HDR as a practical energy source. Recently, reservoir characterization experiments have been carried out to evaluate water loss and reservoir inflation under pressurized conditions over a long time period. In addition, advances have been made in reservoir engineering, seismic modeling, and tracer

D. V. Duchane; D. W. Brown; L. House; B. R. Robinson; R. Ponden

1990-01-01

340

A novel flying hot-wire system  

Microsoft Academic Search

A new flying hot-wire system has been developed for the measurement of highly turbulent and reversing flows. The apparatus is of rectilinear design, incorporating many features which extend its range of application beyond the range of previous designs. One of the advantages of this system is that it is mounted on a flow visualization wind tunnel which allows complementary qualitative

R. M. Kelso; T. T. Lim; A. E. Perry

1994-01-01

341

Hot Air Drying of Green Table Olives  

Microsoft Academic Search

Summary The characteristics of hot air-drying of green table olives (Domat variety) by using a tray dryer were studied. Air temperature varied from 40 to 70 °C with an air velocity of 1 m\\/s. Drying rate curves were determined and quality of dried green olives was evaluated by instrumental analysis (bulk density, particle density, porosity, shrinkage, moisture con- tent, water

Gaye Öngen; Sayit Sargi; Derya Tetik; Timur Köse

342

Minispangling of hot dip galvanized steel  

SciTech Connect

The surface appearance of hot dip galvanized steels can be changed by altering the nucleation and growth of zinc spangles during solidification. This paper describes the spangle nucleation mechanisms resulting from two minispangling techniques: steam impingement and zinc dust impingement. It also characterizes the microscopic surface features of these products and their impact on painted automotive applications.

Patil, R.S.; Henger, G.W.; Glatthorn, R.J.

1984-01-01

343

Modelling of a hot box solar cooker  

Microsoft Academic Search

In this study, the thermal analysis of a hot box solar cooker which is manufactured in ?stanbul Technical University, named as ?.T.U.-2, has been done by using the fourth-order Runge—Kutta method. The results obtained have been given comparatively with the experimental results measured from a cooker.

A Binark; N. Türkmen

1996-01-01

344

"Hot Tub Rash" and "Swimmer's Ear" (Pseudomonas)  

MedlinePLUS

... is Pseudomonas and how can it affect me? Pseudomonas (sue-doh-MOH-nass) aeruginosa is a major cause of infections commonly known as “hot tub rash” and “swimmer’s ear.” This germ is ... (Pseudomonas dermatitis) > Itchy spots on the skin that become ...

345

Nonhormonal therapies for hot flashes in menopause.  

PubMed

Numerous reports in the medical literature and popular media have discussed the effectiveness of various nonhormonal agents in reducing menopausal hot flash symptoms. Data for these therapies are limited, and most of the studies have been conducted in women with a history of breast cancer. Selective serotonin reuptake inhibitors and venlafaxine have been shown to reduce hot flashes by 19 to 60 percent and were well tolerated by study participants. Soy isoflavones reduced hot flashes by 9 to 40 percent in some trials, but most trials showed no difference compared with placebo. Black cohosh and red clover also have had inconsistent results, with some trials showing benefit and some no difference compared with placebo. Soy isoflavones, black cohosh, and red clover were well tolerated in clinical trials. Other agents that have been used to alleviate hot flashes include belladonna/ergotamine tartrate/phenobarbital combination, dong quai, evening primrose oil, gabapentin, ginseng, mirtazapine, trazodone, vitamin E, and wild yam, but few data regarding their effectiveness have been published. Further randomized controlled trials are needed. PMID:16477892

Carroll, Dana G

2006-02-01

346

ULTRASONIC HOT PRESSING OF METALS AND CERAMICS  

Microsoft Academic Search

The feasibility of ultrasonic hot pressing was demonstrated on silver, ; calcium fluoride, and aluminum oxide powders. A hermetically-sealable, force-; insensitive acoustic mounting system was used to penetrate into the high-pressure ; (up to 5000 psi) and high-temperature (up to 2550 deg F) controlled atmosphere ; environment. The density of silver powder compacts was increased as much as 1.6 ;

W. B. Tarpley; H. Kartluke

1961-01-01

347

PSC steam generator hot flow test  

Microsoft Academic Search

The PSC Steam Generator Hot Flow Test was a vibration test of one steam ; generator module installed in the PCRV. Modale number 7, at PCRV location B- 1-; 6, was instrumented with strain gages during fabrication of the steam generator. ; The test was conducted by flowing helium heated by compression of circulators in ; loop number 1 through

1973-01-01

348

CONOCO DOLOMITE HOT GAS CLEANUP SYSTEM  

EPA Science Inventory

This report analyzes a proposal that EPA sponsor a large-scale pilot plant to develop the Conoco (formerly Consol) Dolomite Hot Gas Clean-up system. The report includes a history of the prior development program, the technology involved comparisons with competitive technologies i...

349

Fly a Hot-Air Balloon  

NSDL National Science Digital Library

Learners assemble a hot-air balloon from tissue paper. The heated air (from a heat gun) inside the balloon is less dense than the surrounding air and causes the balloon to float. Use this activity to introduce learners to density and convection currents. Adult supervision recommended when using the heat gun.

Museum Of Science And Industry, Chicago

2012-01-01

350

Plasma deposited rider rings for hot displacer  

DOEpatents

A hot cylinder for a cryogenic refrigerator having two plasma spray deposited rider rings of a corrosion and abrasion resistant material provided in the rider ring grooves, wherein the rider rings are machined to the desired diameter and width after deposition. The rider rings have gas flow flats machined on their outer surface.

Kroebig, Helmut L. (Rolling Hills, CA)

1976-01-01

351

Storage capacity in hot dry rock reservoirs  

DOEpatents

A method of extracting thermal energy, in a cyclic manner, from geologic strata which may be termed hot dry rock. A reservoir comprised of hot fractured rock is established and water or other liquid is passed through the reservoir. The water is heated by the hot rock, recovered from the reservoir, cooled by extraction of heat by means of heat exchange apparatus on the surface, and then re-injected into the reservoir to be heated again. Water is added to the reservoir by means of an injection well and recovered from the reservoir by means of a production well. Water is continuously provided to the reservoir and continuously withdrawn from the reservoir at two different flow rates, a base rate and a peak rate. Increasing water flow from the base rate to the peak rate is accomplished by rapidly decreasing backpressure at the outlet of the production well in order to meet periodic needs for amounts of thermal energy greater than a baseload amount, such as to generate additional electric power to meet peak demands. The rate of flow of water provided to the hot dry rock reservoir is maintained at a value effective to prevent depletion of the liquid

Brown, Donald W. (Los Alamos, NM)

1997-01-01

352

Hot-pressed polycrystalline yttrium iron garnet  

Microsoft Academic Search

A simple hot-pressing system is described which enables small volumes of polycrystalline yttrium iron garnet to be routinely produced. The products have high density, very low second phase content and a controlled grain size. Their magnetic properties compare very favourably with similar polycrystalline material produced by conventional sintering. Sample porosity may be varied in a controlled manner by simple changes

G. A. Naziripour; A. O. Tooke; K. J. Standley; B. E. Storey

1985-01-01

353

Pore collapse and hot spots in HMX  

SciTech Connect

The computing power now available has led researchers to reconsider mesoscale simulations as a means to develop a detailed understanding of detonation waves in a heterogeneous explosive. Since chemical reaction rates are sensitive to temperature, hot spots are of critical importance for initiation. In a plastic-bonded explosive, shock desensitization experiments imply that hot spots generated by pore collapse dominate shock initiation. Here, for the collapse of a single pore driven by a shock, the dependence of the temperature distribution on numerical resolution and dissipative mechanism i s investigated. An inert material (with the constibtive properties of HMX) is used to better focus on the mechanics of pore collapse. ' h o important findings resulted from this study. Eust, too low a resolution can significantly enhance the hot-spot mass. Second, at even moderate piston velocities (< 1W s),s hock dissipation alone does not generate sufficient hot-spot mass. ' b oo ther dissipative mechanism investigated are plastic work and viscous heating. In the cases studied, the integrated lempera!xre distribution has a power-law tail with exponent related to a parameter with dimensions of viscosity. For a particular case, the parameter of either dissipative mechanism can be fit to obtain quantitatively the hot-spot mass needed for initiation. But the dissipative mechanisms scale differently with shock strength and pore size. Consequently, to predict initiation behavior over a range of stimuli and as the micro-stmcture properties of a PBX am varied, sufficient numerical resolution and the correct physical dissipative mechanism are essential.

Menikoff, Ralph

2003-01-01

354

Hot and cold cognition in depression.  

PubMed

We discuss the importance of cognitive abnormalities in unipolar depression, drawing the distinction between "hot" (emotion-laden) and "cold" (emotion-independent) cognition. "Cold" cognitive impairments are present reliably in unipolar depression, underscored by their presence in the diagnostic criteria for major depressive episodes. There is good evidence that some "cold" cognitive abnormalities do not disappear completely upon remission, and that they predict poor response to antidepressant drug treatment. However, in many studies the degree of impairment is moderately related to symptoms. We suggest that "cold" cognitive deficits in unipolar depression may in part be explicable in terms of alterations in "hot" processing, particularly on tasks that utilize feedback, on which depressed patients have been reported to exhibit a "catastrophic response to perceived failure." Other abnormalities in "hot" cognition are commonly observed on tasks utilizing emotionally valenced stimuli, with numerous studies reporting mood-congruent processing biases in depression across a range of cognitive domains. Additionally, an emerging literature indicates reliable reward and punishment processing abnormalities in depression, which are especially relevant for hard-to-treat symptoms such as anhedonia. Both emotional and reward biases are strongly influenced by manipulations of the neurochemical systems targeted by antidepressant drugs. Such a pattern of "hot" and "cold" cognitive abnormalities is consistent with our cognitive neuropsychological model of depression, which proposes central roles for cognitive abnormalities in the generation, maintenance, and treatment of depressive symptoms. Future work should examine in greater detail the role that "hot" and "cold" cognitive processes play in mediating symptomatic improvement following pharmacological, psychological, and novel brain circuit-level interventions. PMID:23481353

Roiser, Jonathan P; Sahakian, Barbara J

2013-03-12

355

Hot spots and hot moments in riparian zones: Potential for improved ...  

Treesearch

In addition to N, this review summarizes current knowledge for phosphorus, ... hot spots and moments occur along the stream/riparian zone/upland interface for a wide ... phosphorus, carbon, pesticides, mercury, transport and fate, watershed ...

356

WESF hot cells waste minimization criteria hot cells window seals evaluation  

SciTech Connect

WESF will decouple from B Plant in the near future. WESF is attempting to minimize the contaminated solid waste in their hot cells and utilize B Plant to receive the waste before decoupling. WESF wishes to determine the minimum amount of contaminated waste that must be removed in order to allow minimum maintenance of the hot cells when they are placed in ''laid-up'' configuration. The remaining waste should not cause unacceptable window seal deterioration for the remaining life of the hot cells. This report investigates and analyzes the seal conditions and hot cell history and concludes that WESF should remove existing point sources, replace cerium window seals in F-Cell and refurbish all leaded windows (except for A-Cell). Work should be accomplished as soon as possible and at least within the next three years.

Walterskirchen, K.M.

1997-03-31

357

Kelley Hot Spring Geothermal Project: Kelly Hot Spring Agricultural Center Conceptual Design.  

National Technical Information Service (NTIS)

The proposed core activity in the Kelly Hot Spring Agricultural Center is a nominal 1200 sow swine raising complex. The swine raising is to be a totally confined operation for producing premium pork in controlled environment facilities that utilize geothe...

A. B. Longyear

1980-01-01

358

Kelly Hot Spring Geothermal Project: Kelly Hot Spring Agricultural Center Preliminary Design. Final Technical Report.  

National Technical Information Service (NTIS)

A Phase 1 Preliminary Design, Construction Planning and Economic Analysis has been conducted for the Kelly Hot Spring Agricultural Center in Modoc County, California. The core activity is a 1360 breeding sow, swine raising complex that utilizes direct hea...

A. B. Longyear

1980-01-01

359

21 CFR 890.5710 - Hot or cold disposable pack.  

Code of Federal Regulations, 2013 CFR

...Identification. A hot or cold disposable pack is a device intended for medical purposes that consists of a sealed plastic bag incorporating chemicals that, upon activation, provides hot or cold therapy for body surfaces. (b)...

2013-04-01

360

1. BLOWER (EXTERIOR CONFIGURATION). Hot Springs National Park Bathhouse ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. BLOWER (EXTERIOR CONFIGURATION). - Hot Springs National Park Bathhouse Row, Maurice Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

361

Single and Cross Hot Wire Anemometry in Incompresible Flow.  

National Technical Information Service (NTIS)

The hot wire calibration and measurement procedures used at the Low Speed Laboratory (LSL) of the Delft University of Technology (TUD) are reviewed and given in the report. The most important fundamental items concerning hot wire anemometry are discussed;...

F. J. M. Wubben

1991-01-01

362

Single and Cross Hot Wire Anemometry in Incompressible Flow.  

National Technical Information Service (NTIS)

An overview of the data acquisition and reduction procedures for constant temperature single and cross hot wire measurements is given. In the framework of a boundary layer study, the available hot wire procedures were reviewed. A number of advantages are ...

F. J. M. Wubben

1991-01-01

363

2. PLENUM WALL, SHOWING PNEUMATIC TUBES. Hot Springs National ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. PLENUM WALL, SHOWING PNEUMATIC TUBES. - Hot Springs National Park, Bathhouse Row, Lamar Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

364

1. View of rmad from jr. hot cell, facing north ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. View of r-mad from jr. hot cell, facing north - Nevada Test Site, Reactor Maintenance & Disassembly Complex, Junior Hot Cell, Jackass Flats, Area 25, South of intersection of Roads F & G, Mercury, Nye County, NV

365

5. HORIZONTAL COOLEDWATER STORAGE TANKS. Hot Springs National Park, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. HORIZONTAL COOLED-WATER STORAGE TANKS. - Hot Springs National Park, Bathhouse Row, Fordyce Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

366

VACUUM PUMP (CONDENSATE RETURN). Hot Springs National Park, Bathhouse ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VACUUM PUMP (CONDENSATE RETURN). - Hot Springs National Park, Bathhouse Row, Hale Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

367

4. VACUUM PUMP (CONDENSATE RETURN). Hot Springs National Park, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. VACUUM PUMP (CONDENSATE RETURN). - Hot Springs National Park, Bathhouse Row, Buckstaff Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 Mile North of U.S. Highway 70, Hot Springs, Garland County, AR

368

ConcepTest: Hot/Cold Water Circulation  

NSDL National Science Digital Library

A fish tank is filled almost to the brim with room temperature water. Two containers of cold and hot water are prepared. Red coloring is added to the hot water, blue coloring is added to the cold water. The cold ...

369

Women with HIV May Suffer More from Hot Flashes  

MedlinePLUS

... JavaScript. Women With HIV May Suffer More From Hot Flashes Small study suggests these patients may need ... evidence is suggesting that menopausal symptoms such as hot flashes may affect them worse than women who ...

370

New Clues about Hot Flashes and The Brain  

MedlinePLUS

... this page, please enable JavaScript. New Clues About Hot Flashes and the Brain Scientists say findings eventually ... MRI Scans WEDNESDAY, July 31 (HealthDay News) -- The hot flashes that bedevil many women going through menopause ...

371

Children in Hot Cars Result in Fatal Consequences  

MedlinePLUS

... Vehicle Safety En Español Holiday & Seasonal Children in Hot Cars Result in Fatal Consequences Emergency physicians are ... dangers associated with leaving anyone, especially children in hot, unventilated vehicles during the summer. Children throughout the ...

372

Exercise Won't Ease Hot Flashes, Study Finds  

MedlinePLUS

... page, please enable JavaScript. Exercise Won't Ease Hot Flashes, Study Finds But it did help a ... Fitness Menopause THURSDAY, Aug. 1 (HealthDay News) -- Easing hot flashes is not among the many benefits that ...

373

Menopausal Hot Flashes Might Be More Intense for Cancer Survivors  

MedlinePLUS

... features on this page, please enable JavaScript. Menopausal Hot Flashes Might Be More Intense for Cancer Survivors ... Cancer survivors have more frequent and severe menopausal hot flashes than other women, a new study reveals. ...

374

Processing maps for hot deformation of rolled AZ31 magnesium alloy plate: Anisotropy of hot workability  

Microsoft Academic Search

Processing maps on rolled AZ31 magnesium plate have been developed in the range 300–550°C and 0.0003–10s?1 by hot compression of specimens parallel to the rolling direction (RD), the transverse direction (TD), or the normal direction (ND) with a view to examine whether the hot workability is anisotropic. The processing map for RD specimens exhibited a single wide domain of workability

Y. V. R. K. Prasad; K. P. Rao

2008-01-01

375

Deformation of oxide scale on steel surface during hot rolling  

Microsoft Academic Search

Although oxide scale has significant influence on surface quality of hot-worked products, deformation of the scale during hot working has not been understood sufficiently. The authors propose an experimental technique to observe the scale as hot-worked using glass coating, in this study. Immediately after hot rolling at 1273K, glass powder was sprinkled over a mild steel sheet. The glass coating

Hiroshi Utsunomiya; Shoichi Doi; Ken-ichiro Hara; Tetsuo Sakai; Shusuke Yanagi

2009-01-01

376

Endolithic Microbial Life in Hot and Cold Deserts  

Microsoft Academic Search

Endolithic microorganisms (those living inside rocks) occur in hot and cold deserts and exist under extreme environmental conditions. These conditions are discussed on a comparative basis. Quantitative estimates of biomass are comparable in hot and cold deserts. Despite the obvious differences between the hot and cold desert environment, survival strategies show some common features. These endolithic organisms are able to

E. Imre Friedmann

1980-01-01

377

Hot cold optimization of large Windows\\/NT applications  

Microsoft Academic Search

A dynamic instruction trace often contains many unnecessary instructions that are required only by the unexecuted portion of the program. Hot-cold optimization (HCO) is a technique that realizes this performance opportunity. HCO uses profile information to partition each routine into frequently executed (hot) and infrequently executed (cold) parts. Unnecessary operations in the hot portion are removed, and compensation code is

Robert S. Cohn; P. Geoffrey Lowney

1996-01-01

378

Closed bioregenerative life support systems: Applicability to hot deserts  

Microsoft Academic Search

Water scarcity in hot deserts, which cover about one-fifth of the Earth’s land area, along with rapid expansion of hot deserts into arable lands is one of the key global environmental problems. As hot deserts are extreme habitats characterized by the availability of solar energy with a nearly complete absence of organic life and water, space technology achievements in designing

Yuriy S. Polyakov; Ibrahim Musaev; Sergey V. Polyakov

2010-01-01

379

Incidence and Management of Hot Flashes in Prostate Cancer  

Microsoft Academic Search

Hot flashes are as common in men who have been castrated due to prostate cancer as hot flashes are in women after menopause. The symptom can cause significant discomfort for a considerable length of time. The hot flashes are most likely caused by a reduction in sex- hormone levels, which, in turn, causes an instability in the hypothalamic thermoregulatory center.

Anna-Clara Spetz; Eva-Lena Zetterlund; Eberhard Varenhorst; Mats Hammar

380

Investigation of Hot Parting Approach to Billet Separation.  

National Technical Information Service (NTIS)

The hot shearing and hot flame cutting concepts of billet separation for use in projectile forging applications were investigated during this project. The hot parting concept of billet separation involves heating 20 to 24 foot lengths of billet stock to f...

D. O. Gustad

1977-01-01

381

Comparison of measured and modelled droplet–hot wall interactions  

Microsoft Academic Search

In this study CFD simulations of both sessile droplets resting upon a vapour cushion and droplets bouncing off a hot solid surface are presented. As a droplet approaches a hot surface the vapour layer formed by evaporation from the droplet acts like a cushion and can prevent contact between the liquid and the hot surface. Rather than hitting and wetting

D. Chatzikyriakou; S. P. Walker; G. F. Hewitt; C. Narayanan; D. Lakehal

2009-01-01

382

The Hot Hand, Competitive Experience, and Performance Differences by Gender  

Microsoft Academic Search

Using data on junior golf tournaments, we find evidence that the “hot hand” does exist, and that its prevalence decreases as golfers gain experience. This provides an explanation as to why studies that consider professional athletes conclude that the hot hand does not exist. We also show that females are much more likely to experience the hot hand compared with

Christopher Cotton; Joseph Price

2006-01-01

383

Design of Hot Stamping Tools with Cooling System  

Microsoft Academic Search

Hot stamping with high strength steel is becoming more popular in automotive industry. In hot stamping, blanks are hot formed and press hardened in a water-cooled tool to achieve high strength. Hence, design of the tool with necessary cooling significantly influences the final properties of the blank and the process time. In this paper a new method based on systematic

H. Hoffmann; H. So; H. Steinbeiss

2007-01-01

384

Martian corona: Nonthermal sources of hot heavy species  

Microsoft Academic Search

We have studied the production of hot O and C atoms, and hot CO2 and CO molecules in the Martian upper atmosphere and exosphere by dissociative recombination (DR) of O2+ and CO+ ions, and sputtering of the atmosphere by incident O+ pick-up ions. Production and collisional thermalization of the hot particles in the upper atmosphere are described by using a

F. Cipriani; F. Leblanc; J. J. Berthelier

2007-01-01

385

An ALARA-conscious hot particle control program  

Microsoft Academic Search

In 1989 approximately twenty-five percent of the radiation dose received by the Point Beach Nuclear Plant (PBNP) Health Physics group was due to its hot particle control program. The Health Physics group initiated a review of the program with the objective of decreasing the dose expenditure for hot particle control while maintaining a high standard for hot particle detection and

W. W. Doolittle; R. S. Bredvad; J. J. Bevelacqua

1992-01-01

386

New hot-water use data for commercial buildings  

Microsoft Academic Search

This article reports that researchers have found that hot water usage in certain commercial buildings may be significantly higher than designers expect. ASHRAE Technical Committee 6.6, Service Water Heating, recognized the need for a comprehensive compilation and evaluation of available hot water usage information in residential and commercial installations. The bulk of the commercial building hot water demand and sizing

W. H. Thrasher; D. W. DeWerth

1994-01-01

387

36 CFR 7.18 - Hot Springs National Park.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Hot Springs National Park. 7.18 Section...OF THE NATIONAL PARK SYSTEM § 7.18 Hot Springs National Park. (a) Commercial... The taking or carrying away of water, hot or cold, from any of the springs,...

2013-07-01

388

21 CFR 880.6085 - Hot/cold water bottle.  

Code of Federal Regulations, 2013 CFR

... 2013-04-01 2013-04-01 false Hot/cold water bottle. 880.6085 Section...Personal Use Miscellaneous Devices § 880.6085 Hot/cold water bottle. (a) Identification. A hot/cold water bottle is a device intended...

2013-04-01

389

Test methods for evaluating hot cracking: Review and perspective.  

National Technical Information Service (NTIS)

The phenomenon of hot cracking is described and discussed, and criteria for tests to assess hot cracking are elucidated. The historical development of hot cracking tests is traced from the 1930s to present, with categorization of tests into several types....

G. M. Goodwin

1990-01-01

390

Hot cell measuring and test equipment calibration control  

Microsoft Academic Search

The need for increasingly accurate date on the performance of fuels and materials in nuclear reactors has placed increased emphasis on the quality of measurement of data obtained in hot cells. A program was proposed to incorporate the basic features of a standard measurement laboratory while recognizing the unique aspect of hot cell measurements. That hot cells must comply with

K. J. Taylor

1979-01-01

391

What's hot and what's not: tracking most frequent items dynamically  

Microsoft Academic Search

Most database management systems maintain statistics on the underlying relation. One of the important statistics is that of the “hot items” in the relation: those that appear many times (most frequently, or more than some threshold). For example, end-biased histograms keep the hot items as part of the histogram and are used in selectivity estimation. Hot items are used as

Graham Cormode; S. Muthukrishnan

2005-01-01

392

25. Hot well, as seen from port side aft. Waste ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

25. Hot well, as seen from port side aft. Waste water overflow pipe appears at left, behind which is bilge pump. At base of hot well on either side are reciprocating boiler feedwater pumps driven from hot well crosshead. (Labels were applied by HAER recording team and are not original to equipment.) - Ferry TICONDEROGA, Route 7, Shelburne, Chittenden County, VT

393

10 CFR 431.102 - Definitions concerning commercial water heaters, hot water supply boilers, and unfired hot water...  

Code of Federal Regulations, 2013 CFR

... Energy 3 2013-01-01 2013-01-01 false Definitions concerning commercial water heaters, hot water supply boilers, and unfired hot water storage tanks. 431.102 Section 431.102 Energy DEPARTMENT OF ENERGY ENERGY...

2013-01-01

394

Interstellar Chemistry - Hot-Ion Reactions  

NASA Astrophysics Data System (ADS)

We have explored the possible significance on interstellar chemistry of translation ally excited ions (`hot ions') produced in exothermic reactions, focusing on weaknesses that remain in existing gas-phase models of cloud chemistry. Particular instances are the lack of success in accounting for observed abundances of NH3, N2H+ and cyanopolyacetylenes. When `hot-ion' reactions are included in the ion-molecule model we obtain predicted abundances in cold clouds like TMC-1, agreeing very well with observations (to better than one order of magnitude) for virtually all smaller molecules included in the model. In particular, the discrepancies for NH3, N2H+ and cyanopolyacetylenes no longer arise. This occurs in the time regime 106.3-106.5 yr [note that this is not the time where the abundance of complex species go through a maximum (˜105.5 yr) but somewhat later] and not for very old clouds (age > 107.5 yr). If we use rate constants for hydrogen atom abstraction reactions based on current estimates of their activation energies, then the `hot-ion' reactions do not lead to a noticeable increase in the production of longer chain hydrocarbons. However, for smaller values of these activation energies (for example, those that might make the rate constants around 10-11 cm-3 s-1), such hot-ion reactions could dramatically increase the efficiency of carbon-chain building by gas-phase reactions. Therefore, these hot-ion processes may ultimately prove to be the basis of the build-up of these larger species in cold clouds. If the build-up of long chains is to be attributed to the effect of these hot-ion reactions, then the unexpectedly gradual decline in the abundances of CnH, with increasing n, is readily explained. It seems plausible to attribute the irregular variation in these abundances to the enhanced rate of ion-dipolar processes as compared with ion-non-polar reactions, although such influences are more pronounced at greater cloud ages (> 107.5 yr).

Brown, R. D.; Cragg, D. M.; Bettens, R. P. A.

1990-08-01

395

Kawasaki Steel Giho, Vol. 22, No. 3, 1990. Special Issue on Hot Metal Pretreatment.  

National Technical Information Service (NTIS)

Contents: Total Hot Metal Pretreatment System at Kawasaki Steel; Desiliconization Process of Hot Metal at Blast Furnace Casthouse; Hot Metal Dephosphorization Treatment in Torpedo Car at Chiba Works; Desulphurization Treatment of Hot Metal in Torpedo Car;...

1990-01-01

396

10 CFR 431.102 - Definitions concerning commercial water heaters, hot water supply boilers, and unfired hot water...  

Code of Federal Regulations, 2010 CFR

...unfired hot water storage tanks. 431.102 Section 431.102 Energy DEPARTMENT OF ENERGY...ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM...Unfired Hot Water Storage Tanks § 431.102...to the amount of energy consumed by the...Unfired hot water storage tank means a...

2009-01-01

397

10 CFR 431.102 - Definitions concerning commercial water heaters, hot water supply boilers, and unfired hot water...  

Code of Federal Regulations, 2010 CFR

...unfired hot water storage tanks. 431.102 Section 431.102 Energy DEPARTMENT OF ENERGY...ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM...Unfired Hot Water Storage Tanks § 431.102...to the amount of energy consumed by the...Unfired hot water storage tank means a...

2010-01-01

398

Heat stress in hot U. S. mines and criteria for standards for mining in hot environments. Informational report  

Microsoft Academic Search

The Mining Enforcement and Safety Administration conducted a comprehensive environmental study in underground and surface mines of the United States to determine the prevalent combinations of air temperature, humidity, radiative heat, and wind speed in hot mines. The study has shown that most of the surveyed mines are 'hot' in terms of existing industrial hygiene standards for hot work sites.

F. L. Misaqi; J. G. Inderberg; P. D. Blumenstein; T. Naiman

1976-01-01

399

HOT WATER DRILL FOR TEMPERATE ICE.  

USGS Publications Warehouse

The development of a high-pressure hot-water drill is described, which has been used reliably in temperate ice to depths of 400 meters with an average drill rate of about 1. 5 meters per minute. One arrangement of the equipment weighs about 500 kilograms, and can be contained on two sleds, each about 3 meters long. Simplified performance equations are given, and experiments with nozzle design suggest a characteristic number describing the efficiency of each design, and a minimum bore-hole diameter very close to 6 centimeters for a hot water drill. Also discussed is field experience with cold weather, water supply, and contact with englacial cavities and the glacier bed.

Taylor, Philip, L.

1984-01-01

400

An Optimization Study of Hot Stamping Operation  

NASA Astrophysics Data System (ADS)

In the present study, 3-dimensional finite element analyses for hot-stamping processes of Audi B-pillar product are conducted using JSTAMP/NV and HEEDS. Special attention is paid to the optimization of simulation technology coupling with thermal-mechanical formulations. Numerical simulation based on FEM technology and optimization design using the hybrid adaptive SHERPA algorithm are applied to hot stamping operation to improve productivity. The robustness of the SHERPA algorithm is found through the results of the benchmark example. The SHERPA algorithm is shown to be far superior to the GA (Genetic Algorithm) in terms of efficiency, whose calculation time is about 7 times faster than that of the GA. The SHERPA algorithm could show high performance in a large scale problem having complicated design space and long calculation time.

Ghoo, Bonyoung; Umezu, Yasuyoshi; Watanabe, Yuko; Ma, Ninshu; Averill, Ron

2010-06-01

401

Enabling Technologies for Ceramic Hot Section Components  

SciTech Connect

Silicon-based ceramics are attractive materials for use in gas turbine engine hot sections due to their high temperature mechanical and physical properties as well as lower density than metals. The advantages of utilizing ceramic hot section components include weight reduction, and improved efficiency as well as enhanced power output and lower emissions as a result of reducing or eliminating cooling. Potential gas turbine ceramic components for industrial, commercial and/or military high temperature turbine applications include combustor liners, vanes, rotors, and shrouds. These components require materials that can withstand high temperatures and pressures for long duration under steam-rich environments. For Navy applications, ceramic hot section components have the potential to increase the operation range. The amount of weight reduced by utilizing a lighter gas turbine can be used to increase fuel storage capacity while a more efficient gas turbine consumes less fuel. Both improvements enable a longer operation range for Navy ships and aircraft. Ceramic hot section components will also be beneficial to the Navy's Growth Joint Strike Fighter (JSF) and VAATE (Versatile Affordable Advanced Turbine Engines) initiatives in terms of reduced weight, cooling air savings, and capability/cost index (CCI). For DOE applications, ceramic hot section components provide an avenue to achieve low emissions while improving efficiency. Combustors made of ceramic material can withstand higher wall temperatures and require less cooling air. Ability of the ceramics to withstand high temperatures enables novel combustor designs that have reduced NO{sub x}, smoke and CO levels. In the turbine section, ceramic vanes and blades do not require sophisticated cooling schemes currently used for metal components. The saved cooling air could be used to further improve efficiency and power output. The objectives of this contract were to develop technologies critical for ceramic hot section components for gas turbine engines. Significant technical progress has been made towards maturation of the EBC and CMC technologies for incorporation into gas turbine engine hot-section. Promising EBC candidates for longer life and/or higher temperature applications relative to current state of the art BSAS-based EBCs have been identified. These next generation coating systems have been scaled-up from coupons to components and are currently being field tested in Solar Centaur 50S engine. CMC combustor liners were designed, fabricated and tested in a FT8 sector rig to demonstrate the benefits of a high temperature material system. Pretest predictions made through the use of perfectly stirred reactor models showed a 2-3x benefit in CO emissions for CMC versus metallic liners. The sector-rig test validated the pretest predictions with >2x benefit in CO at the same NOx levels at various load conditions. The CMC liners also survived several trip shut downs thereby validating the CMC design methodology. Significant technical progress has been made towards incorporation of ceramic matrix composites (CMC) and environmental barrier coatings (EBC) technologies into gas turbine engine hot-section. The second phase of the program focused on the demonstration of a reverse flow annular CMC combustor. This has included overcoming the challenges of design and fabrication of CMCs into 'complex' shapes; developing processing to apply EBCs to 'engine hardware'; testing of an advanced combustor enabled by CMCs in a PW206 rig; and the validation of performance benefits against a metal baseline. The rig test validated many of the pretest predictions with a 40-50% reduction in pattern factor compared to the baseline and reductions in NOx levels at maximum power conditions. The next steps are to develop an understanding of the life limiting mechanisms in EBC and CMC materials, developing a design system for EBC coated CMCs and durability testing in an engine environment.

Venkat Vedula; Tania Bhatia

2009-04-30

402

Hot corrosion behavior of Nimonic-75  

SciTech Connect

Hot corrosion studies were conducted on Nimonic-75 superalloy in pure Na{sub 2}SO{sub 4} and 90% Na{sub 2}SO{sub 4} + 10% NaCl environments at 900 C for different time intervals. The results showed that Nimonic-75 exhibits good hot corrosion resistance in pure sodium sulfate, and the corrosion rate was enhanced considerably in the presence of 10% NaCl environment. It is also evident that the corrosion rate is time dependent and that the diffusion of corrosive species occurred toward the substrate. Based on these observations, an electrochemical model is proposed to show that the degradation of Nimonic-75 is an electrochemical phenomenon.

Gurrappa, I. [Research Centre Julich (Germany)

1997-10-01

403

Hot water, fresh beer, and salt  

SciTech Connect

In the hot chocolate effect'' the best musical scales (those with the finest tone quality, largest range, and best tempo) are obtained by adding salt to a glass of hot water supersaturated with air. Good scales can also be obtained by adding salt to a glass of freshly opened beer (supersaturated with CO{sub 2}) provided you first (a) get rid of much of the excess CO{sub 2} so as to produce smaller, hence slower, rising bubbles, and (b) get rid of the head of foam, which damps the standing wave and ruins the tone quality. Finally the old question, Do ionizing particles produce bubbles in fresh beer '' is answered experimentally.

Crawford, F.S. (Lawrence Berkeley Laboratory, Berkeley, CA (USA) Physics Department, University of California, Berkeley, CA (USA))

1990-11-01

404

Photo-thermo-chemistry of hot atmospheres  

NASA Astrophysics Data System (ADS)

We have developed a new model to study the atmosphere of exoplanets adapted to the characteristics of the atmospheres of hot Jupiters and hot Neptunes. Such a model appears essential to interpret recent and future observations, to predict the composition and to understand the formation and the evolution of these planetary bodies. As the chemistry of nitrogen compounds is not well constrained, we investigated several sub-networks for nitrogen-bearing species and investigate their impact on the predicted abundances and spectra of HD 189733b. We present these results. An important problem of photochemicalmodels is the lack of high temperature photochemical data. In order to improve this situation, we have begun a campaign of measurement of VUV absorption cross section at high temperature for H2O, CO2 and NH3. We will present the influence of these new experimental data on the thermo-photochemicalmodel.

Venot, O.; Hébrard, E.; Agundez, M.; Dobrijevic, M.; Selsis, F.; Hersant, F.; Bounaceur, R.; Bénilan, Y.; Gazeau, M.-C.; Fray, N.; Iro, N.

2012-09-01

405

Method for hot pressing beryllium oxide articles  

DOEpatents

The hot pressing of beryllium oxide powder into high density compacts with little or no density gradients is achieved by employing a homogeneous blend of beryllium oxide powder with a lithium oxide sintering agent. The lithium oxide sintering agent is uniformly dispersed throughout the beryllium oxide powder by mixing lithium hydroxide in an aqueous solution with beryllium oxide powder. The lithium hydroxide is converted in situ to lithium carbonate by contacting or flooding the beryllium oxide-lithium hydroxide blend with a stream of carbon dioxide. The lithium carbonate is converted to lithium oxide while remaining fixed to the beryllium oxide particles during the hot pressing step to assure uniform density throughout the compact.

Ballard, Ambrose H. (Oak Ridge, TN); Godfrey, Jr., Thomas G. (Oak Ridge, TN); Mowery, Erb H. (Clinton, TN)

1988-01-01

406

Hot hydrogen in the exosphere of Venus  

Microsoft Academic Search

Lyman-alpha measurements of the hydrogen corona of Venus by Mariners 5 and 10 have been shown to be consistent with a two-temperature component model. Bertaux et al. (1978) have successfully fitted the Venera 9 exospheric Lyman-alpha data to an elevated (500 K) single temperature. Various source mechanisms have been proposed to explain the 'hot' (1000 K) energetic component of the

T. E. Cravens; T. Gombosi; A. F. Nagy

1980-01-01

407

STOVL hot gas ingestion control technology  

Microsoft Academic Search

This paper reports on a comprehensive wind tunnel test program conducted to evaluate control of Hot Gas Ingestion (HGI) on a 9.2 percent scale model of the McDonnell Aircraft Company model 279-3C advanced Short Takeoff and Vertical Landing (STOVL) configuration. The test was conducted in the NASA-Lewis Research Center 9 ft by 15 ft Low Speed Wind Tunnel during the

K. C. Amuedo; B. R. Williams; J. D. Flood; A. L. Johns

1991-01-01

408

Plasmonically enhanced hot electron based photovoltaic device.  

PubMed

Hot electron photovoltaics is emerging as a candidate for low cost and ultra thin solar cells. Plasmonic means can be utilized to significantly boost device efficiency. We separately form the tunneling metal-insulator-metal (MIM) junction for electron collection and the plasmon exciting MIM structure on top of each other, which provides high flexibility in plasmonic design and tunneling MIM design separately. We demonstrate close to one order of magnitude enhancement in the short circuit current at the resonance wavelengths. PMID:23546103

Atar, Fatih B; Battal, Enes; Aygun, Levent E; Daglar, Bihter; Bayindir, Mehmet; Okyay, Ali K

2013-03-25

409

Method for polymer hot embossing process development  

Microsoft Academic Search

Molding technologies associated with fabricating macro scale polymer components such as injection molding and hot embossing\\u000a have been adapted with considerable success for fabrication of polymer microparts. While the basic principles of the process\\u000a remain the same, the precision with which the processing parameters need to be controlled especially in the case of molding\\u000a high aspect ratio (HAR) polymer microparts

Proyag Datta; Jost Goettert

2007-01-01

410

New aspects of simulation in hot embossing  

Microsoft Academic Search

Hot embossing is especially well suited for manufacturing small and medium-volume series. However, wider diffusion of this\\u000a process currently is seriously hampered by the lack of adequate simulation tools for process optimization and part design.\\u000a This lack of simulation tools is becoming critical, as the dimensions of the microstructures continuously shrink from micron\\u000a and sub-micron to nano scales and as

M. Worgull; M. Heckele

2004-01-01

411

Terahertz superconducting hot-electron bolometer mixers  

Microsoft Academic Search

Hot-electron bolometer frequency down-converters (mixers) based on superconducting films have been found to offer record sensitivity for THz receivers to be used in radio astronomy. In this paper we focus on mixers using NbN phonon-cooled devices. We show that recent theoretical models predict a performance that agrees well with experiments. Important mixer properties such as conversion efficiency, noise (sensitivity), and

S. Cherednichenko; P. Khosropanah; E. Kollberg; M. Kroug; H. Merkel

2002-01-01

412

Hot Spot Mutations in Adenosine Deaminase Deficiency  

Microsoft Academic Search

We have previously characterized mutant adenosine deaminase (ADA; adenosine aminohydrolase, EC 3.5.4.4) enzymes in seven children with partial ADA deficiency. Six children shared common origins, suggesting a common progenitor. However, we found evidence for multiple phenotypically different mutant enzymes. We hypothesized that many of the mutations would be at CpG dinucleotides, hot spots at which spontaneous deamination of 5-methylcytosine results

Rochelle Hirschhorn; Stephanie Tzall; Amy Ellenbogen

1990-01-01

413

Menopausal Women's Perceived Causes of Hot Flash  

Microsoft Academic Search

This descriptive study examined the perceptions of a group of breast cancer survivors about the causes of their hot flashes. Thirty-nine participants readily offered 1,008 individual responses. A content analysis revealed four prominent categories (stress, pain, medication related, and lack of sleep) as well as others (e.g., food related, heat related). In the context of concerns about biomedical approaches to

Margaret L. Stubbs; Susan M. Cohen; Feridey Carr

2008-01-01

414

Hot Electron-Induced Electrogenerated Chemiluminescence  

Microsoft Academic Search

\\u000a In this chapter, we discuss the basics of cathodic hot electron-induced electrogenerated chemiluminescence (HECL). In the\\u000a applications of HECL, we discuss, e.g., the usable electrode materials and their advantages as well as the applicable solution\\u000a conditions in aqueous media. We also summarize the luminophore types excitable by this method and their usability as labels\\u000a in practical bioaffinity assay applications.

Johanna Suomi; Sakari Kulmala

415

Hot gas source and fuel therefor  

SciTech Connect

A hot gas generator is described comprising: a reaction chamber having an outlet therefrom; a source of an aqueous solution in the range of about 21% to about 55% hydrogen peroxide by weight in homogeneous mixture with an exothermically burnable substance in an amount to support combustion, the source extending to the reaction chamber for dispersion of the mixture therein; and a permeable mass of a catalyst for decomposition of the hydrogen peroxide in the reaction chamber between the source and the outlet.

Delchev, N.E.; Tzonev, O.N.

1987-10-13

416

Cold Probes of the Hot Universe  

Microsoft Academic Search

High-resolution x-ray spectroscopy is becoming a powerful tool for studying the hot (1 - 100 MK) and dynamic universe. The grating spectrometers on the XMM and Chandra satellites have sparked a new era in x-ray astronomy, but there is need to deploy instrumentation that can provide higher spectral resolution with high throughput in the Fe-K band (around 6 keV) and

Caroline Kilbourne

2007-01-01

417

A new hot-tearing criterion  

NASA Astrophysics Data System (ADS)

A new criterion for the appearance of hot tears in metallic alloys is proposed. Based upon a mass balance performed over the liquid and solid phases, it accounts for the tensile deformation of the solid skeleton perpendicular to the growing dendrites and for the induced interdendritic liquid feeding. This model introduces a critical deformation rate (dot \\varepsilon _{p,max } ) beyond which cavitation, i.e., nucleation of a first void, occurs. As should be expected, this critical value is an increasing function of the thermal gradient and permeability and a decreasing function of the viscosity. The shrinkage contribution, which is also included in the model, is shown to be of the same order of magnitude as that associated with the tensile deformation of the solid skeleton. A hot-cracking sensitivity (HCS) index is then defined as dot \\varepsilon _{_{p,max } }^{ - 1} . When applied to a variable-concentration aluminum-copper alloy, this HCS criterion can reproduce the typical “? curves” previously deduced by Clyne and Davies on a phenomenological basis. The calculated values are in fairly good agreement with those obtained experimentally by Spittle and Cushway for a non-grain-refined alloy. A comparison of this criterion to hot cracks observed in ring-mold solidification tests indicates cavitation depression of a few kilo Pascal and tensile stresses in the coherent mushy zone of a few mega Pascal. These values are discussed in terms of those obtained by other means (coherency measurement, microporosity observation, and simulation). Even though this HCS criterion is based only upon the appearance of a first void and not on its propagation, it sets up for the first time a physically sound basis for the study of hot-crack formation.

Rappaz, M.; Drezet, J.-M.; Gremaud, M.

1999-02-01

418

Dark spot downstream from nonlinear hot image.  

PubMed

The dark spot effect downstream from the nonlinear hot image is accounted for in this paper. The conditions for the formation of dark spot are carefully discussed. The explanation is based on analytical analysis, and the results are verified by numerical simulations. The dependence of the location of the dark spot on the nonlinear phase delay seems to suggest a probable method for measuring the nonlinear refractive coefficient of materials. PMID:22772099

Jia, Huaiting; Zhou, Lidan; Wang, Fang

2012-07-01

419

Sustainable Energy - Without the hot air  

Microsoft Academic Search

Reader John Roeder writes about a website associated with David MacKay's book Sustainable Energy-Without the hot air. The book is a freely downloadable PDF (or purchasable) book describing an analysis detailing a low-carbon renewable energy transformation route for a large, modern first world industrial country (the United Kingdom). Written for the layman, the work uses vernacular language, e.g., energy consumption

Dan MacIsaac

2009-01-01

420

Solar-hot-water-heater lease program  

Microsoft Academic Search

Ten domestic hot-water solar systems were installed, leased to homeowners, and monitored for two years. All of the systems were installed as back-ups to electric water heaters. The systems consist of two to four collectors, a solar storage tank (as well as the existing non-solar heater), and a heat exchanger package. Eight are three-collector systems, one is a four-collector and

Rutherford

1983-01-01

421

Thermal Processes Governing Hot-Jupiter Radii  

NASA Astrophysics Data System (ADS)

There have been many proposed explanations for the larger-than-expected radii of some transiting hot Jupiters, including either stellar or orbital energy deposition deep in the atmosphere or deep in the interior. In this paper, we explore the important influences on hot-Jupiter radius evolution of (1) additional heat sources in the high atmosphere, the deep atmosphere, and deep in the convective interior; (2) consistent cooling of the deep interior through the planetary dayside, nightside, and poles; (3) the degree of heat redistribution to the nightside; and (4) the presence of an upper atmosphere absorber inferred to produce anomalously hot upper atmospheres and inversions in some close-in giant planets. In particular, we compare the radius expansion effects of atmospheric and deep-interior heating at the same power levels and derive the power required to achieve a given radius increase when night-side cooling is incorporated. We find that models that include consistent day/night cooling are more similar to isotropically irradiated models when there is more heat redistributed from the dayside to the nightside. In addition, we consider the efficacy of ohmic heating in the atmosphere and/or convective interior in inflating hot Jupiters. Among our conclusions are that (1) the most highly irradiated planets cannot stably have uB >~ 10 km s–1 G over a large fraction of their daysides, where u is the zonal wind speed and B is the dipolar magnetic field strength in the atmosphere, and (2) that ohmic heating cannot in and of itself lead to a runaway in planet radius.

Spiegel, David S.; Burrows, Adam

2013-07-01

422

Some hot topics in animal bioacoustics.  

PubMed

This paper is derived from a "Hot Topics in Animal Bioacoustics" presentation at the 130th meeting of the Acoustical Society of America in St. Louis, Missouri. Six bioacoustics studies on a wide variety of species are discussed. Two of the studies are concerned with insects, the parasitoid fly, and cotton bollworms. The remaining bioacoustics studies are on aquatic animals including the West Indian manatee, elephant seals, and dolphins. PMID:9165723

Au, W W

1997-05-01

423

Hot-carrier luminescence in Si  

Microsoft Academic Search

There has been a renewed interest in the spectra of emitted light from Si metal-oxide-semiconductor field-effect transistors (MOSFET's) in the belief that a better understanding of this phenomenon will lead to a deeper understanding of hot carriers in these devices. In this paper, we attempt to explain the physical mechanisms responsible for the light emission in Si under varying doping

Jeff Bude; Nobuyuki Sano; Akira Yoshii

1992-01-01

424

Legionella Infection Risk from Domestic Hot Water  

Microsoft Academic Search

We investigated Legionella and Pseudomonas con- tamination of hot water in a cross-sectional multicentric sur- vey in Italy. Chemical parameters (hardness, free chlorine, and trace elements) were determined. Legionella spp. were detected in 33 (22.6%) and Pseudomonas spp. in 56 (38.4%) of 146 samples. Some factors associated with Legionella contamination were heater type, tank distance and capacity, water plant age,

Paola Borella; M. Teresa Montagna; Vincenzo Romano-Spica; Serena Stampi; Giovanna Stancanelli; Maria Triassi; Rachele Neglia; Isabella Marchesi; Guglielmina Fantuzzi; Daniela Tatò; Christian Napoli; Gianluigi Quaranta; Patrizia Laurenti; Erica Leoni; Giovanna De Luca; Cristina Ossi; Matteo Moro; Gabriella Ribera D'Alcalà

2004-01-01

425

HOT CARRIER EFFECTS WITHIN MACROSCOPIC TRANSPORT MODELS  

Microsoft Academic Search

The distribution function of hot carriers in state-of-the-art devices is insu ciently de-scribed using just the electric eld or the average carrier energy as parameters. Still, the standard models to describe carrier transport in semiconductor devices, namely the drift-di usion model and the energy-transport model rely on these assumptions. In this article we summarize our work on six moments transport

TIBOR GRASSER; HANS KOSINA; SIEGFRIED SELBERHERR

426

Magnetic screening length in hot QCD  

NASA Astrophysics Data System (ADS)

In hot QCD, static chromomagnetic fields are screened, contrary to magnetic fields in electromagnetic plasmas. The inverse of the magnetic Debye mass measures the screening length. In this talk I reformulate a well-known definition of the magnetic Debye mass as a correlator between spin 0 operators. This means that the magnetic Debye mass -like its electric counterpart- is the mass of a state with the appropriate quantum numbers. This gives a useful consistency check in simulations.

Giovannangeli, Pierre

2005-06-01

427

Hot gas in galaxy groups: recent observations  

NASA Astrophysics Data System (ADS)

Galaxy groups are the least massive systems where the bulk of baryons begin to be accounted for. Not simply the scaled-down versions of rich clusters following self-similar relations, galaxy groups are ideal systems to study baryon physics, which is important for both cluster cosmology and galaxy formation. We review the recent observational results on the hot gas in galaxy groups. The first part of this paper is on the scaling relations, including x-ray luminosity, entropy, gas fraction, baryon fraction and metal abundance. Compared to clusters, groups have a lower fraction of hot gas around the center (e.g. r < r2500), but may have a comparable gas fraction at large radii (e.g. r2500 < r < r500). Better constraints on the group gas and baryon fractions require sample studies with different selection functions and deep observations at r > r500 regions. The hot gas in groups is also iron-poor at large radii (0.3r500-0.7 r500). The iron content of the hot gas within the central regions (r < 0.3r500) correlates with the group mass, in contrast to the trend of the stellar mass fraction. It remains to be seen where the missing iron in low-mass groups is. In the second part, we discuss several aspects of x-ray cool cores in galaxy groups, including their difference from cluster cool cores, radio AGN heating in groups and the cold gas in group cool cores. Because of the vulnerability of the group cool cores to radio AGN heating and the weak heat conduction in groups, group cool cores are important systems to test the AGN feedback models and the multiphase cool-core models. At the end of the paper, some outstanding questions are listed.

Sun, M.

2012-04-01

428

Reduced metal consumption in hot pipe rolling  

Microsoft Academic Search

Means of reducing the metal consumption in the hot rolling of seamless pipe are considered. The most common is the use of\\u000a square or round continuous-cast billet. The trimming required for Pilger mills may be reduced by preparation of the front\\u000a ends of the sleeves in skew rolling and rolling of the rear end at the free section of the

Yu. S. Krivchenko; V. F. Balakin; Yu. D. Ugryumov; G. N. Kushchinskii; V. V. Perchanik; D. Yu. Ugryumov

2010-01-01

429

Elliptical instability in hot Jupiter systems  

NASA Astrophysics Data System (ADS)

Several studies have already considered the influence of tides on the evolution of systems composed of a star and a close-in companion to tentatively explain different observations such as the spin-up of some stars with hot Jupiters, the radius anomaly of short orbital period planets and the synchronization or quasi-synchronization of the stellar spin in some extreme cases. However, the nature of the mechanism responsible for the tidal dissipation in such systems remains uncertain. In this paper, we claim that the so-called elliptical instability may play a major role in these systems, explaining some systematic features present in the observations. This hydrodynamic instability, arising in rotating flows with elliptical streamlines, is suspected to be present in both planet and star of such systems, which are elliptically deformed by tides. The presence and the influence of the elliptical instability in gaseous bodies, such as stars or hot Jupiters, are most of the time neglected. In this paper, using numerical simulations and theoretical arguments, we consider several features associated to the elliptical instability in hot-Jupiter systems. In particular, the use of ad hoc boundary conditions makes it possible to estimate the amplitude of the elliptical instability in gaseous bodies. We also consider the influence of compressibility on the elliptical instability, and compare the results to the incompressible case. We demonstrate the ability for the elliptical instability to grow in the presence of differential rotation, with a possible synchronized latitude, provided that the tidal deformation and/or the rotation rate of the fluid are large enough. Moreover, the amplitude of the instability for a centrally-condensed mass of fluid is of the same order of magnitude as for an incompressible fluid for a given distance to the threshold of the instability. Finally, we show that the assumption of the elliptical instability being the main tidal dissipation process in eccentric inflated hot Jupiters and misaligned stars is consistent with current data.

Cébron, David; Bars, Michael Le; Gal, Patrice Le; Moutou, Claire; Leconte, Jeremy; Sauret, Alban

2013-11-01

430

Temperature effects on hot wire anemometer calibrations  

Microsoft Academic Search

Calibrations of a miniature DISA hot wire anemometer probe over a range of wire temperatures and a narrow range of ambient temperatures have been correlated by a simple expression (Ne)(Tm\\/To)a=A+B(Re)n. Values of a and n, which are expected to remain roughly constant for wires of similar geometry, were found to be 0.67 and 0.45 respectively. The value of a is

F A Koch; I S Gartshore

1972-01-01

431

An Electrical Hot-Wire Inclinometer  

Microsoft Academic Search

The hot-wire inclinometer consists essentially of two fine platinum wires (diameter about 0.1 mm.) mounted parallel to one another in a closed chamber at a distance apart equal to about 1 mm. A constant current of from 0.4 to 1.5 ampere (according to the sensitivity desired) is maintained in the wires, which constitute two of the arms of a Wheatstone

J S G Thomas

1919-01-01

432

Criteria for hot tap welding further studies  

SciTech Connect

EWI has developed new criteria for hot tap welding that allows safe welding procedures to be developed easily for all ferritic steels. The approach is based on a simple field measurement of the heat sink capacity of the linepipe, that is, the ability of the linepipe to conduct heat. Subsequent correlation of the heat sink capacity to the cooling rate of the weld will allow the welding engineer to develop suitable welding procedures that reduce the susceptibility to cracking. Gas metal arc welding trails have been conducted on simulated branch and sleeve connections in the laboratory to determine the criteria for cracking when using ER80S-D2 and ER70S-3 consumables. Simulated branch and sleeve connections have been made with various consumables (E7018 and E6010) on live pipelines containing natural gas. The weld cooling rates and the extent of cracking were determined to validate criteria established for safe hot tap welding. The results of this investigation clearly demonstrate the feasibility of producing economical and structurally sound hot tap repairs with a high level of confidence.

Not Available

1989-05-26

433

Hot gas in clusters of galaxies  

SciTech Connect

The origin, space distribution, and emission of the hot intergalactic gas in galaxy clusters are discussed. This gas may have been left over from the period when the clusters were formed. According to the adiabatic theory of galaxy formation, primordial gas would have become heated and compressed into hot, thin pancake-shaped structures, representing protoclusters. As the primordial gas crosses the shock waves bounding the protocluster, its temperature and entropy will rise significantly. The gas not consumed in the formation of galaxies will remain in the hot phase, enriched with heavy elements from supernova explosions in the cluster members and from galactic winds. This gas will retain the entropy acquired during the contraction process, but its temperature will be governed by the depth of the cluster potential well. The primordial entropy of intracluster gas is estimated from this theory, and the results are compared with x-ray observations of clusters. The best fit is achieved for a nuclear region of 0.3-Mpc radius. Temperature fluctuations ..delta..T/Tapprox. = (1--2) x 10/sup -4/ in the microwave background radiation are inferred, depending only weakly on the model parameters.

Doroshkevich, A.G.; Klypin, A.A.

1979-03-01

434

Estimate LAMOST hot star's parameters by POLLUX  

NASA Astrophysics Data System (ADS)

With the highest efficiency of gathering spectra by LAMOST telescope, a large number of spectra have been obtained during commissioning observation, which included a lot of spectra of O type star. It’s a difficult task to obtain accurate parameters for hot star, lacking of a good model. Several stellar models, such as MAFAGS, ATLAS, Marcs etc, do not cover the parameter range which temperature exceeds 25000K. POLLUX is a database of synthetic stellar spectra, in which CMFGEN provides atmosphere models for the O type stars (Teff >25000K) [5]. A method of estimating stellar parameters for hot stars is presented in this paper, based on matching LAMOST observed spectra with the theoretical spectra library. We convert the resolution of CMFGEN spectra, which is about 150000 to LAMOST resolution of 2000. By comparing with the CMFGEN template spectra, we can obtain the parameters of observed hot stars. Estimation for the errors of the final parameters shows that low efficiency of LAMOST blue arms of the spectrographs does not affect O type star observations.

Zuo, Fang; Luo, Ali; Zhang, Jiannan

2012-09-01

435

Hot air vulcanization of rubber profiles  

SciTech Connect

Elastomer profiles are deployed in quantity by the automobile industry as seals and wateproofing in coachwork. The high standards demanded by the industry; improvement in weather prediction, noise reduction, restriction of tolerances, together with powerful demand for EPDM force the rubber processing industry into development, particularly of elastomers. Complex proofing systems must also be achieved with extremely complicated profile forms. All too often such profiles have an extremely large surface together with a low cross-section density. They frequently consist of two or three rubber compounds and are steel reinforced. Sometimes they are flocked and coated with a low friction finish. Such high-tech seals require an adjustment of the vulcanization method. The consistent trend in the nineties towards lower quantities of elastomer per sealing unit and the dielectric factor, especially with EPDM, has brought an old fashioned vulcanization method once more to the fore, a method developed over the past years to an extremely high standard, namely the hot-air method. This paper describes various vulcanization and curing methods and their relative merits and disadvantages, the Gerlach hot-air concept, the hot air installation concept, and energy saving and efficiency afforded by this technique. 4 figs.

Gerlach, J.

1995-07-01

436

Baroclinic instability on hot extrasolar planets  

NASA Astrophysics Data System (ADS)

We investigate baroclinic instability in flow conditions relevant to hot extrasolar planets. The instability is important for transporting and mixing heat, as well as for influencing large-scale variability on the planets. Both linear normal mode analysis and non-linear initial-value calculations are carried out - focusing on the freely-evolving, adiabatic situation. Using a high-resolution general circulation model (GCM) which solves the traditional primitive equations, we show that large-scale jets similar to those observed in current GCM simulations of hot extrasolar giant planets are likely to be baroclinically unstable, on a timescale of a few to a few tens of planetary rotations, generating cyclones and anticyclones that drive weather systems. The growth rate and scale of the most unstable mode obtained in the linear analysis are in qualitative, good agreement with the full non-linear calculations. In general, unstable jets evolve differently depending on their signs (eastward or westward), due to the change in sign of the jet curvature. For jets located at or near the equator, instability is strong at the flanks - but not at the core. Crucially, the instability is either poorly or not at all captured in simulations with low resolution and/or high artificial viscosity. Hence, the instability has not been observed or emphasized in past circulation studies of hot extrasolar planets.

Polichtchouk, I.; Cho, J. Y.-K.

2012-08-01

437

Hydrate melting in soil around hot conductor  

SciTech Connect

There is ice in the Gulf of Mexico, and this type of ice called gas hydrates burns when ignited. Gas hydrates form slowly within the soil mass when the gas seeping up from offshore oil reservoirs mixes with water under high pressures (>500 m of water) and low temperatures (a few degrees Celsius). The oil travels from the well to the platform through a conductor pipe. The oil and therefore the conductor are very hot and melt the existing hydrates that are within the depth of the foundation piles. The melting process generates a large amount of gas that can endanger the stability of the foundation. The rate at which the temperature rises around the hot conductor in the hydrate rich soil is studied using the finite-element method (FEM). A detailed thermodynamic analysis is performed. It includes a laboratory experiment to help validate FEM, a study of the mesh size, the thermodynamic analysis results, a study of the conductor size, and of the latent heat influence. The results can be used to evaluate the temperature rise around a hot pipe buried in soil and therefore the propagation of the hydrate melting front around the conductor and toward the piles.

Briaud, J.L. [Texas A and M Univ., College Station, TX (United States). Dept. of Civil Engineering; Chaouch, A. [ATSER Engineering and Environmental Co., Houston, TX (United States)

1997-07-01

438

Hot Dry Rock Geothermal Energy Development Program  

SciTech Connect

During Fiscal Year 1987, emphasis in the Hot Dry Rock Geothermal Energy Development Program was on preparations for a Long-Term Flow Test'' of the Phase II'' or Engineering'' hot dry rock energy system at Fenton Hill, New Mexico. A successful 30-day flow test of the system during FY86 indicated that such a system would produce heat at a temperature and rate that could support operation of a commercial electrical power plant. However, it did not answer certain questions basic to the economics of long-term operation, including the rate of depletion of the thermal reservoir, the rate of water loss from the system, and the possibility of operating problems during extended continuous operation. Preparations for a one-year flow test of the system to answer these and more fundamental questions concerning hot dry rock systems were made in FY87: design of the required surface facilities; procurement and installation of some of their components; development and testing of slimline logging tools for use through small-diameter production tubing; research on temperature-sensitive reactive chemical tracers to monitor thermal depletion of the reservoir; and computer simulations of the 30-day test, extended to modeling the planned Long-Term Flow Test. 45 refs., 34 figs., 5 tabs.

Smith, M.C.; Hendron, R.H.; Murphy, H.D.; Wilson, M.G.

1989-12-01

439

Hot filament CVD of boron nitride films  

DOEpatents

Using a hot filament (.apprxeq.1400.degree. C.) to activate borazine (B.sub.3 N.sub.3 H.sub.6) molecules for subsequent reaction with a direct line-of-sight substrate, transparent boron ntiride films as thick as 25,000 angstroms are grown for a substrate temperature as low as 100.degree. C. The minimum temperature is determined by radiative heating from the adjacent hot filament. The low temperature BN films show no indication of crystallinity with X-ray diffraction (XRD). X-ray photoelectron spectra (XPS) show the films to have a B:N ratio of 0.97:1 with no other XPS detectable impurities above the 0.5% level. Both Raman and infrared (IR) spectroscopy are characteristic of h-BN with small amounts of hydrogen detected as N-H and B-H bands in the IR spectrum. An important feature of this method is the separation and localization of the thermal activation step at the hot filament from the surface reaction and film growth steps at the substrate surface. This allows both higher temperature thermal activation and lower temperature film growth.

Rye, Robert R. (Albuquerque, NM)

1992-01-01

440

On-chip hot spot cooling using silicon thermoelectric microcoolers  

NASA Astrophysics Data System (ADS)

Thermal management of microprocessors has become an increasing challenge in recent years because of localized high flux hot spots which cannot be effectively removed by conventional cooling techniques. This paper describes the use of the silicon chip itself as a thermoelectric cooler to suppress the hot spot temperature. A three-dimensional analytical thermal model of the silicon chip, including localized thermoelectric cooling, thermoelectric heating, silicon Joule heating, hot spot heating, background heating, and conductive/convective cooling on the back of the silicon chip, is developed and used to predict the on-chip hot spot cooling performance. The effects of hot spot size, hot spot heat flux, silicon chip thickness, microcooler size, doping concentration in the silicon, and parasitic Joule heating from electric contact resistance on the cooling of on-chip hot spots, are investigated in detail.

Wang, Peng; Bar-Cohen, Avram

2007-08-01

441

Hot Particles of the Second Kind in Flood Lands of the Yenisei River  

Microsoft Academic Search

Specific modification of hot particles found in flood-land soils of the Yenisei River was studied. In contrast to the known hot particles (hot particles of the first kind), newly found hot particles are referred to as hot particles of the second kind. Abundance, radionuclide composition, and other characteristics of hot particles of the first and second kinds are compared.

Z. G. Gritchenko; Yu. V. Kuznetsov; V. K. Legin; V. N. Strukov; B. F. Myasoedov; A. P. Novikov; A. E. Shishlov; Yu. V. Savitskii

2001-01-01

442

Hot carriers relaxation in highly excited polar semiconductors: Hot phonons versus phonon-plasmon coupling  

NASA Astrophysics Data System (ADS)

We present a study of the photo-excited charge carriers relaxation dynamics in polar semiconductors comparing calculations to pump probe experiments. Hot carrier densities in the 1018cm-3 range can easily be photo-generated using moderately intense optical excitations. This can lead to known phenomena, namely, hot phonon populations and the coupling of polar optical phonons with plasmon modes. However, these two phenomena can affect the hot carriers relaxation and have never been examined together. This is a problem for the theoretical study of future Hot Carrier Solar Cells, where the conditions allow both of these phenomena to occur. The charge carriers dynamics and the coupling of polar optical phonons with plasmon modes are treated by a Full Band Ensemble Monte Carlo simulation code featuring a self-consistent dielectric function. To take into consideration hot phonon populations and the subsequent phonon bottleneck for the carriers relaxation, the charge carriers simulation code is coupled to a phonon dedicated Ensemble Monte Carlo code. This enables for the first time an accurate study of both the charge carriers and phonon systems dynamics, the latter being most of the time overly simplified in previous studies. The present work explores to which extent the two aforementioned phenomena affect the photo-generated charge carriers relaxation in GaAs and can be easily adapted to other polar semiconductors.

Tea, Eric; Hamzeh, Hani; Aniel, Frédéric

2011-12-01

443

Hot spot mutations in adenosine deaminase deficiency.  

PubMed Central

We have previously characterized mutant adenosine deaminase (ADA; adenosine aminohydrolase, EC 3.5.4.4) enzymes in seven children with partial ADA deficiency. Six children shared common origins, suggesting a common progenitor. However, we found evidence for multiple phenotypically different mutant enzymes. We hypothesized that many of the mutations would be at CpG dinucleotides, hot spots at which spontaneous deamination of 5-methylcytosine results in C to T or G to A transitions. Digestion of DNA from these children with Msp I and Taq I, enzymes recognizing CpG dinucleotides, identified three different mutations, each correlating with expression of a different mutant enzyme. Sequencing of cDNA clones and genomic DNA amplified by polymerase chain reaction confirmed the presence of C to T or G to A transitions at CpG dinucleotides (C226 to T, G446 to A, and C821 to T, resulting in Arg76 to Trp, Arg149 to Gln, and Pro274 to Leu). A "null" mutation, also found in two ADA-deficient severe combined immunodeficient children, was serendipitously detected as gain of a site for Msp I. Simultaneous loss of a site for Bal I defined the precise base substitution (T320 to C, Leu107 to Pro), confirmed by sequence analysis. To determine the true frequency of hot spot mutation in these children, consecutively ascertained through a newborn screening program, we sequenced cDNA from the remaining alleles. Two others were hot spot mutations (C631 to T and G643 to A, resulting in Arg211 to Cys and Ala215 to Thr), each again resulting in expression of a phenotypically different mutant enzyme. Only one additional mutation (previously identified by us) is not in a hot spot. These seven mutations account for all 14 chromosomes in these children. There is thus a very high frequency of hot spot mutations in partial ADA deficiency. Most of these children carry two different mutant alleles. We were able to correlate genotype and phenotype and to dissect the activity of individual mutant alleles. Images

Hirschhorn, R; Tzall, S; Ellenbogen, A

1990-01-01

444

Cold Friends of Hot Jupiters: AO Survey  

NASA Astrophysics Data System (ADS)

Hot Jupiters” are a class of gas giant planets found in extrasolar systems at very small orbital distances (?0.05 AU). We know that these planets could not have formed at their present locations, but must instead have migrated in from beyond the ice line. One class of proposed migration mechanisms for these planets involve gravitational perturbations from a distant stellar companion. These same processes also provide a natural explanation for the existence of a subset of hot Jupiters that have been observed to have orbits that are highly misaligned with respect to their star's spin axis and/or have large orbital eccentricities. In the "Cold Friends" survey, we search for stellar companions around 51 stars known to host hot Jupiters in order to determine whether stellar companions play an important role in hot Jupiter migration. Our survey consists of a population of stars with planets that have eccentric and/or misaligned orbits as well as a control population of planets with well-aligned and circular orbits. This project searches for companion stars (the "Cold Friends") in three detection modes: radial velocity monitoring, high resolution IR spectroscopy (presented by D. Piskorz et al. at this meeting), and adaptive optics (AO) imaging at infrared wavelengths (presented here). The AO mode is sensitive to the most distant companions (separations of 50-200 AU and beyond) while the other modes are effective at finding companions at smaller separations. We present the results of our AO survey and discuss the binary fraction found in our sample. Out of our total sample of 51 stars, 19 candidate companions (many of which have not been observed before) were directly imaged around 17 stars. We also describe follow-up photometry and astrometry of all detected companions to determine whether or not they are gravitationally bound to the primary planet-hosting star. If such companions are common, it would suggest that perturbations from stellar companions may play a significant role in the evolution of hot Jupiter systems.

Ngo, Henry; Knutson, H. A.; Hinkley, S.; Crepp, J. R.; Batygin, K.; Howard, A. W.; Johnson, J. A.; Morton, T. D.; Muirhead, P. S.

2013-10-01

445

HOT CELL BUILDING, TRA632. CONTEXTUAL AERIAL VIEW OF HOT CELL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

HOT CELL BUILDING, TRA-632. CONTEXTUAL AERIAL VIEW OF HOT CELL BUILDING, IN VIEW AT LEFT, AS YET WITHOUT ROOF. PLUG STORAGE BUILDING LIES BETWEEN IT AND THE SOUTH SIDE OF THE MTR BUILDING AND ITS WING. NOTE CONCRETE DRIVE BETWEEN ROLL-UP DOOR IN MTR BUILDING AND CHARGING FACE OF PLUG STORAGE. REACTOR SERVICES BUILDING (TRA-635) WILL COVER THIS DRIVE AND BUTT UP TO CHARGING FACE. DOTTED LINE IS ON ORIGINAL NEGATIVE. TRA PARKING LOT IN LEFT CORNER OF THE VIEW. CAMERA FACING NORTHWESTERLY. INL NEGATIVE NO. 8274. Unknown Photographer, 7/2/1953 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

446

An evaluation of lead concentrations in imported hot sauces.  

PubMed

In the last decade, the U.S. Food and Drug Administration (FDA) has issued several warnings and recalls for food products that exceed FDA standards for lead. Products containing chili peppers and salt were often suspected as sources of lead contamination, and included items such as candy that are routinely investigated. However, products such as hot sauces that contain similar ingredients have not been the focus of evaluations. This study quantified lead concentrations in imported hot sauces, evaluated product compliance to existing United States standards, and calculated potential dietary lead exposure for children using the Integrated Exposure Uptake Biokinetic Model. Finally, recommendations for reducing the risk of lead exposure from hot sauces are provided. Twenty-five (25) bottles of imported hot sauces manufactured in Mexico and South America were purchased in Clark County, Nevada. All hot sauces were analyzed for lead concentrations, pH, and leaded packaging. Hot sauces were analyzed by inductively coupled plasma mass spectrometry and packaging was analyzed using x-ray fluorescence technology. Four brands of hot sauces (16%) exceeded 0.1 ppm lead, the current FDA action level for lead in candy. Hot sauces with lead concentrations >0.1 ppm lead contained salt and were manufactured in Mexico. Subsequent analysis of additional lots of hot sauces exceeding 0.1 ppm lead revealed inconsistent lead concentrations between and within manufacturer lots. The lead concentrations of the plastic hot sauce lids ranged from below the limit of detection to 2,028 ppm lead. There was no association between lead concentrations in hot sauces and pepper type. These results indicate the need for more rigorous screening protocols for products imported from Mexico, the establishment of an applicable standard for hot sauce, and resources to allow for the enforcement of existing food safety policies. The data reported herein represent the first known investigation of lead concentrations in hot sauces. PMID:23581685

Berger Ritchie, Jennifer A; Gerstenberger, Shawn L

2013-01-01

447

[History of hot spring bath treatment in China].  

PubMed

As early as the 7th century B.C. (Western Zhou Dynasty), there is a recording as 'spring which contains sulfur could treat disease' on the Wentang Stele written by WANG Bao. Wenquan Fu written by ZHANG Heng in the Easten Han Dynasty also mentioned hot spring bath treatment. The distribution of hot springs in China has been summarized by LI Daoyuan in the Northern Wei Dynasty in his Shuijingzhu which recorded hot springs in 41 places and interpreted the definition of hot spring. Bencao Shiyi (by CHEN Cangqi, Tang Dynasty) discussed the formation of and indications for hot springs. HU Zai in the Song Dynasty pointed out distinguishing hot springs according to water quality in his book Yuyin Conghua. TANG Shenwei in the Song Dynasty noted in Jingshi Zhenglei Beiji Bencao that hot spring bath treatment should be combined with diet. Shiwu Bencao (Ming Dynasty) classified hot springs into sulfur springs, arsenicum springs, cinnabar springs, aluminite springs, etc. and pointed out their individual indications. Geologists did not start the work on distribution and water quality analysis of hot springs until the first half of the 20th century. There are 972 hot springs in Wenquan Jiyao (written by geologist ZHANG Hongzhao and published in 1956). In July 1982, the First National Geothermal Conference was held and it reported that there were more than 2600 hot springs in China. Since the second half of the 20th century, hot spring sanatoriums and rehabilitation centers have been established, which promoted the development of hot spring bath treatment. PMID:22169492

Hao, Wanpeng; Wang, Xiaojun; Xiang, Yinghong; Gu Li, A Man; Li, Ming; Zhang, Xin

2011-07-01

448

Method for hot press forming articles  

DOEpatents

This disclosure relates to an improved method for achieving the best bond strength and for minimizing distortion and cracking of hot pressed articles. In particular, in a method for hot press forming both an outer facing circumferential surface of and an inner portion of a hub, and of bonding that so-formed outer facing circumferential surface to an inner facing circumferential surface of a pre-formed ring thereby to form an article, the following improvement is made. Normally, in this method, the outside ring is restrained by a restraining sleeve of ring-shaped cross-section having an inside diameter. A die member, used to hot press form the hub, is so-formed as to have an outside diameter sized to engage the inside diameter of the restraining sleeve in a manner permitting relative movement therebetween. The improved method is one in which several pairs of matched restraining sleeve and die member are formed with each matched pair having a predetermined diameter. The predetermined diameter of each matched pair is different from another matched pair by stepped increments. The largest inside diameter of a restraining sleeve is equal to the diameter of the outer facing circumferential surface of the hub. Each pair of the matched restraining sleeve and die member is used to form an article in which an inside hub is bonded to an outside ring. The several samples so-formed are evaluated to determine which sample has the best bond formed between the hub and the ring with the least or no cracking or distortion in the ring portion of the article. Thereafter, the matched restraining sleeve and die member which form the article having the best bonding characteristics and least distortion cracking is then used for repeated formations of articles.

Baker, Robert R. (Livonia, MI); Hartsock, Dale L. (Livonia, MI)

1982-01-01

449

Nanostructuring of polymers by hot embossing lithography  

NASA Astrophysics Data System (ADS)

While researchers of ever more advanced NGL systems are still struggling to demonstrate the feasibility to manufacture features well below 100 nm at an affordable cost and a reasonable throughput, nanoimprint technologies are emerging as a possible answer to these challenges. 100 nm patterns are imprinted with a fully patterned 4 inch diameter stamp in a low-temperature embossing process. In low temperature imprinting processes with polymers having very low glass transition temperatures heating and cooling cycles are minimized. This enables to increase the throughput of a hot embossing process, which is important for potential industrial applications.

Scheer, Hella-Christin; Glinsner, Thomas; Wissen, Matthias; Pelzer, Rainer

2004-05-01

450

Chemical identifications of possible martian hot spots  

NASA Astrophysics Data System (ADS)

If the interpretation of certain Mars Global Surveyor images indicating recent ground water seepage and surface runoff (1) is correct, it may imply that Mars can still be active internally in some places from time to time, and outgassing of certain molecules from the interior could occur with or without the water seepage. Although there is no evidence of active volcanism on Mars today, ``localized'' outgassing sources, the ``hot spots'', may not be ruled out. If outgassing does occur somewhere on Mars, water, carbon dioxide, sulfur species, methane, and to a lesser extent, halogens, would be the likely molecules of outgassing, based on the terrestrial analogs. The sulfur species, methane and halogens have not been detected in the ``global'' observations of Mars. Considering the possibility of outgassing from some localized hot spots, we have developed a one-dimensional photochemical model (2) that includes methane (CH_4), sulfur dioxide (SO_2) and hydrogen sulfide (H_2S), starting with their current ``global average'' upper limits of, respectively, 0.02, 0.1 and 0.1 ppm at the surface, and then progressively increasing their abundances above possible hot spots. Halogens are neglected as they are a minor product of the terrestrial outgassing sources. We find that the introduction of methane into the martian atmosphere results in the formation of mainly formaldehyde, methyl alcohol (CH_3OH) and ethane (C_2H_6), whereas the introduction of the sulfur species produces mainly sulfur monoxide (SO) and sulfuric acid (H_2SO_4). In a relatively short time of an hour, ordinary convective processes alone can reduce the mixing ratios of outgassed species by factors of 10^4 -- 10^5 approximately 50 km from the source, and the time for spreading the source material more or less uniformly over the planet (with corresponding dilution factor of ˜10^8) would be approximately one year. Depending upon the flux of the outgassed molecules from possible hot spots, some of these species, especially CH_4, SO_2, H_2S, and perhaps CH_2O, may be detectable locally, either by remote sensing or in situ measurements. References: (1) Malin, M. C. and K. S. Edgett, Science 288, 2330, 2000; (2) Wong, A. S., S. K. Atreya, and Th. Encrenaz, J. Geophys. Res., in press, 2003.

Wong, A. S.; Atreya, S. K.; Renno, N. O.

2003-04-01

451

HotRecorder 2.0.1  

NSDL National Science Digital Library

When having online conversations, sometimes a mere emoticon just won't do. For those who are looking to add a bit of variety to such social interactions, there is the HotRecorder application. With this program, users can record and add "emotisounds" to voice communications that take place over the Internet. The program works in conjunction with a number of such communication tools, including Skype, Google Talk and Yahoo Messenger 7. Other helpful features include a number of recording tools and some detailed search features. This application is compatible with Windows XP/2003 server.

452

Characterizing hot spots throughout the catchment  

NASA Astrophysics Data System (ADS)

Few catchments in the world are left truly undisturbed. Rather, they are under anthropogenic stress for a variety of reasons ranging from climate forcing to meeting the basic water allocation needs of the population. Reduction in the number of inundation areas has significantly decreased the nutrient and organic matter retention capacity along the river corridor, with major consequences for the both the riverine and coastal ecosystems. Cumulative stress may build up to a "tipping point" which can cause a change or set of changes which could occur non-linearly. In order to mitigate the environmental stress on these ecosystems, management plans are created to balance the needs of the dependent populations and those of ecology. While these catchment-wide plans aim to improve the ecological function of aquatic areas over the large scale, this sledge-hammer approach ignores the inherent heterogeneity in the catchment. Societal (and policy) decisions involve more than abiotic quantification of water storage and flow. A more encompassing ecohydrological view facilitates a more rounded policy framework that has flexibility to accommodate multiple social drivers, and one that can accommodate an "ecosystem improvement" rather than single species improvement. Not every spot in the landscape is equally valuable for specific societal values. Areas of high activity may provide the resilience capacity necessary to prevent catastrophic changes. In times of ecological instability, ecosystem resilience is of paramount importance in maintaining essential ecosystem services. Hot spots of biogeochemical cycling will occur where unique situations arise, such as areas of surface and groundwater interaction, creating spots of localized, high activity. In order to understand the systems' potential to support various habitat niches in the large scale, the identification of specific hot spots or hot moments is necessary. A basal understanding of the concurrent biogeochemical cycles enables the subsequent predictions of the alternative ecosystem responses. This study aims to understand the where and why of hot spots in selected catchments in southeastern Australia and Midwestern United States. The ecosystem response to changes in the catchment will be generated based on various biotic parameters, with the ultimate goal of incorporation into a policy framework at the catchment scale.

Welti, N.; Lockington, D.; Jakeman, T.; Hunt, R.

2012-04-01

453

Automated inspection of hot steel slabs  

DOEpatents

The disclosure relates to a real time digital image enhancement system for performing the image enhancement segmentation processing required for a real time automated system for detecting and classifying surface imperfections in hot steel slabs. The system provides for simultaneous execution of edge detection processing and intensity threshold processing in parallel on the same image data produced by a sensor device such as a scanning camera. The results of each process are utilized to validate the results of the other process and a resulting image is generated that contains only corresponding segmentation that is produced by both processes. 5 figs.

Martin, R.J.

1985-12-24

454

Control of dephasing in rotationally hot molecules  

SciTech Connect

We consider a rotationally hot diatomic molecule as an example of an open quantum system, where molecular vibrational wave packets are subject to dephasing due to rovibrational coupling. We report analytical and numerical results addressing whether the dephasing rate can be controlled by adjustment of the initial wave packet phases. It appears that over long time scales, phase-only control is not possible, but for earlier time scales the possibility of phase-only control of dephasing remains. In addition, we point out that the time dependence of the dephasing process depends significantly upon the degeneracy of the rotational environment states.

Bartram, David; Ivanov, Misha [Blackett Laboratory, Imperial College London, Prince Consort Road, South Kensington, London SW7 2AZ (United Kingdom)

2010-04-15

455

Particulate hot gas stream cleanup technical issues  

SciTech Connect

The analyses of hot gas stream cleanup particulate samples and descriptions of filter performance studied under this contract were designed to address problems with filter operation that have been linked to characteristics of the collected particulate matter. One objective of this work was to generate an interactive, computerized data bank of the key physical and chemical characteristics of ash and char collected from operating advanced particle filters and to relate these characteristics to the operation and performance of these filters. The interactive data bank summarizes analyses of over 160 ash and char samples from fifteen pressurized fluidized-bed combustion and gasification facilities utilizing high-temperature, high pressure barrier filters.

Pontius, D.H.; Snyder, T.R.

1999-09-30

456

Automated inspection of hot steel slabs  

DOEpatents

The disclosure relates to a real time digital image enhancement system for performing the image enhancement segmentation processing required for a real time automated system for detecting and classifying surface imperfections in hot steel slabs. The system provides for simultaneous execution of edge detection processing and intensity threshold processing in parallel on the same image data produced by a sensor device such as a scanning camera. The results of each process are utilized to validate the results of the other process and a resulting image is generated that contains only corresponding segmentation that is produced by both processes.

Martin, Ronald J. (Burnsville, MN)

1985-01-01

457

Constrained caloric curves for hot nuclei  

NASA Astrophysics Data System (ADS)

Simulations based on experimental data obtained from multifragmenting quasi-fused nuclei produced in central 129Xe + natSn collisions have been used to deduce event by event freeze-out properties on the thermal excitation energy range 4-12 AMeV. From such properties, information on constrained caloric curves has been derived. At constant average volumes caloric curves exhibit a monotonous behavior whereas for constrained pressures backbending is observed. Such results support the existence of a first order phase transition for hot nuclei.

Borderie, B.; Piantelli, S.; Rivet, M.-F.; Raduta, Ad. R.

2012-07-01

458

Ion diffusion at interfaces in hot plasmas  

SciTech Connect

There are many laboratory applications in which it is important to know how fast two hot, ionized materials mix across an initially sharp interface. The speed of this process is regulated by the interdiffusion coefficient for the species involved. In a previous work, a theoretical method for calculating the interdiffusion coefficient in a Binary Ionic Mixture (classical ions in a uniform, neutralizing background) was described and found to give excellent agreement with Molecular Dynamics estimates. The purpose of this report is to show how these results may be applied to a model of the plasma interface, including electric field effects, to give a good description of the mixing across it.

Boercker, D.B.; Warren, K.; Haggin, G.

1986-04-01

459

Advanced Hot-Gas Desulfurization Sorbents  

SciTech Connect

The objective of this project is to develop advanced hot-gas desulfurization sorbents for relatively low temperature application that show stable and high sulfidation reactivity at 343 to 538 {degrees}C. A number of zinc-based formulations will be prepared and screened for testing in a fixed-bed reactor at high pressure (1 to 20 atm) and high temperatures using simulated coal-derived fuel gases. One of the superior formulations will be tested for long- term durability and chemical reactivity in the reactor. To prevent sulfation, catalyst additives will be investigated, which would promote a lower regeneration temperature.

Jothimurugesan, K.; Adeyiga, A. [Department of Chemical Engineering, Hampton, Univ., VA (United States); Gangwal, S.K. [Research Triangle Inst., Research Triangle Park, NC (United States)

1996-12-31

460

Hot Colors- Windows into Hidden Worlds  

NSDL National Science Digital Library

This website contains an electronic field trip based on Yellowstone National Park's hot springs and the microorganisms living in them. The site includes a link for teachers providing an introduction, overview of concepts explored in the trip, lesson plans, and additional web links. The electronic field trip may be viewed in a low bandwidth version without downloading. For a high bandwith version of the field trip, Macromedia Flash Player is required and can be downloaded on site. Further information on system requirements and field trip procedures are outlined on the website as well.

Foundation, Thermal B.; Foundation, Yellowstone P.

461

6.NS Making Hot Cocoa, Variation 2  

NSDL National Science Digital Library

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: A recipe for hot chocolate calls for 3 cups of milk. What fraction of the recipe can Nelli make with $\\frac23$ cups of milk? Solve the problem by drawi...

462

6.NS Making Hot Cocoa, Variation 1  

NSDL National Science Digital Library

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: One mug of hot chocolate uses $\\frac23$ cup of cocoa powder. How many mugs can Nelli make with 3 cups of cocoa powder? Solve the problem by drawing a p...

463

METHOD OF HOT ROLLING URANIUM METAL  

DOEpatents

A method is given for quickly and efficiently hot rolling uranium metal in the upper part of the alpha phase temperature region to obtain sound bars and sheets possessing a good surface finish. The uranium metal billet is heated to a temperature in the range of 1000 deg F to 1220 deg F by immersion iii a molten lead bath. The heated billet is then passed through the rolls. The temperature is restored to the desired range between successive passes through the rolls, and the rolls are turned down approximately 0.050 inch between successive passes.

Kaufmann, A.R.

1959-03-10

464

Hot cell shield plug extraction apparatus  

DOEpatents

An apparatus is provided for moving shielding plugs into and out of holes in concrete shielding walls in hot cells for handling radioactive materials without the use of external moving equipment. The apparatus provides a means whereby a shield plug is extracted from its hole and then swung approximately 90 degrees out of the way so that the hole may be accessed. The apparatus uses hinges to slide the plug in and out and to rotate it out of the way, the hinge apparatus also supporting the weight of the plug in all positions, with the load of the plug being transferred to a vertical wall by means of a bolting arrangement.

Knapp, Philip A. (Moore, ID); Manhart, Larry K. (Pingree, ID)

1995-01-01

465

Effect of Controlled Cooling After Hot Rolling on Mechanical Properties of Hot Rolled TRIP Steel  

Microsoft Academic Search

A three-step cooling pattern on the runout table (ROT) was conducted for the hot rolled TRIP steel. Microstructural evolution during thermomechanical controlled processing (TMCP) was investigated. Processing condition of controlled cooling on a ROT in the laboratory rolling mill was discussed. The results indicated that the micro-structure containing polygonal ferrite, granular bainite and a significant amount of the stable retained

Di WU; Zhuang LI; Hui-sheng LÜ

2008-01-01

466

Getting into hot water Problematizing hot water service demand: The case of Old Cairo  

Microsoft Academic Search

This dissertation analyzes hot water demand and service infrastructure in two neighboring but culturally distinct communities of the urban poor in the inner-city area of central Cairo. The communities are the Historic Islamic Cairo neighborhood of Darb Al Ahmar at the foot of Al-Azhar park, and the Zurayib neighborhood of Manshiyat Nasser where the Coptic Zabaleen Recyclers live. The study

Thomas Henry Culhane

2010-01-01

467

Hot dry rock geothermal potential of Roosevelt Hot Springs area: review of data and recommendations  

SciTech Connect

The Roosevelt Hot Springs area in west-central Utah possesses several features indicating potential for hot dry rock (HDR) geothermal development. The area is characterized by extensional tectonics and a high regional heat flow of greater than 105 mW/m/sup 2/. The presence of silicic volcanic rocks as young as 0.5 to 0.8 Myr and totaling 14 km/sup 3/ in volume indicates underlying magma reservoirs may be the heat source for the thermal anomaly. Several hot dry wells have been drilled on the periphery of the geothermal field. Information obtained on three of these deep wells shows that they have thermal gradients of 55 to 60/sup 0/C/km and bottom in impermeable Tertiary granitic and Precambrian gneissic units. The Tertiary granite is the preferred HDR reservoir rock because Precambrian gneissic rocks possess a well-developed banded foliation, making fracture control over the reservoir more difficult. Based on a fairly conservative estimate of 160 km/sup 2/ for the thermal anomaly present at Roosevelt Hot Springs, the area designated favorable for HDR geothermal exploration may be on the order of seven times or more than the hydrogeothermal area currently under development.

East, J.

1981-05-01

468

Hot-Callusing Device for Tree Grafting: Method and Apparatus for Hot-Callusing Graft Unions.  

National Technical Information Service (NTIS)

The hot-callusing method and apparatus of the invention direct heat to the graft union area of plants or trees to accelerate the callusing of the stock and scion while leaving the remaining plant parts unheated. The apparatus comprises a tube having openi...

H. B. Lagerstedt

1981-01-01

469

Gas pressurized hot embossing for transcription of micro-features  

Microsoft Academic Search

Hot embossing has proven productive for the parallel replication of precision micro-features onto thermoplastic substrates at low cost. During conventional hot embossing, the substrate and the stamp are brought into contact and are compressed directly by the hot plates of the machine. The accuracy and area of replication are limited due to the inherent non-uniform pressure distribution. Si-wafers are too

J.-H. Chang; S.-Y. Yang

2003-01-01

470

Notes on home-type solar hot water economics  

SciTech Connect

Some things to consider before buying a solar hot water system is first discussed. Approximate savings in energy costs for a family of four with a solar hot water system are given. Buying a solar hot water system with money taken out of a savings account and with money borrowed on a bank card is next discussed. Finally, some comments are given on tracking parabolic through solar collectors vs flat plate collectors for residential systems.

Drumheller, K.

1984-01-01

471

A Search for Companions in Kepler's Hot Jupiter Systems  

NASA Astrophysics Data System (ADS)

The presence or absence of additional, short-period planets in hot Jupiter systems is an important observational constraint on models of planet formation and dynamical evolution. Among the over 1000 Kepler exoplanet candidates is a large number of hot Jupiter candidates. We present results from a search for additional planets in these systems through a combination of photometric, geometric, and dynamical (TTV) probes. The results of this search may provide useful insight into the histories and orbital architectures of hot Jupiter systems.

Steffen, Jason H.; Holman, M.; Borucki, W. J.; Koch, D. G.; Kepler Science Team

2011-05-01

472

Austempering of Hot Rolled Si-Mn TRIP Steels  

Microsoft Academic Search

The austempering after hot rolling in hot rolled Si-Mn TRIP (transformation-induced plasticity) steels was investigated. The mechanism of TRIP was discussed through examination of the microstructure and the mechanical properties of this kind of steel. The results showed that the strain-induced transformation to martensite of retained austenite occurs in hot rolled Si-Mn TRIP steels. The sample exhibited a good combination

Zhuang LI; Di WU; Rong HU

2006-01-01

473

DECOMMISSIONING OF HOT CELL FACILITIES AT THE BATTELLE COLUMBUS LABORATORIES  

SciTech Connect

Battelle Columbus Laboratories (BCL), located in Columbus, Ohio, must complete decontamination and decommissioning activities for nuclear research buildings and grounds at its West Jefferson Facilities by 2006, as mandated by Congress. This effort includes decommissioning several hot cells located in the Hot Cell Laboratory (Building JN-1). JN-1 was originally constructed in 1955, and a hot cell/high bay addition was built in the mid 1970s. For over 30 years, BCL used these hot cell facilities to conduct research for the nuclear power industry and several government agencies, including the U.S. Navy, U.S. Army, U.S. Air Force, and the U.S. Department of Energy. As a result of this research, the JN-1 hot cells became highly contaminated with mixed fission and activation products, as well as fuel residues. In 1998, the Battelle Columbus Laboratories Decommissioning Project (BCLDP) began efforts to decommission JN-1 with the goal of remediating the site to levels of residual contamination allowing future use without radiological restrictions. This goal requires that each hot cell be decommissioned to a state where it can be safely demolished and transported to an off-site disposal facility. To achieve this, the BCLDP uses a four-step process for decommissioning each hot cell: (1) Source Term Removal; (2) Initial (i.e., remote) Decontamination; (3) Utility Removal; and (4) Final (i.e., manual) Decontamination/Stabilization. To date, this process has been successfully utilized on 13 hot cells within JN-1, with one hot cell remaining to be decommissioned. This paper will provide a case study of the hot cell decommissioning being conducted by the BCLDP. Discussed will be the methods used to achieve the goals of each of the hot cell decommissioning stages and the lessons learned that could be applied at other sites where hot cells need to be decommissioned.

Weaver, Patrick; Henderson, Glenn; Erickson, Peter; Garber, David

2003-02-27

474

Hot-electron reliability and ESD latent damage  

Microsoft Academic Search

The impact of noncatastrophic electrostatic discharge (ESD) stress on hot-electron reliability as well as the effect of hot-electron (HE) injection on the ESD protection threshold are discussed. It is found that there is a factor-of-two-to-four deterioration in hot-electron reliability after low-level ESD stress. These two effects can be viewed as similar although HE is a low-current long-time process and ESD

Shian Aur; Amitava Chatterjee; Thomas Polgreen

1988-01-01

475

Calculating the optimum temperature for serving hot beverages  

Microsoft Academic Search

Hot beverages such as tea, hot chocolate, and coffee are frequently served at temperatures between 160°F (71.1°C) and 185°F (85°C). Brief exposures to liquids in this temperature range can cause significant scald burns. However, hot beverages must be served at a temperature that is high enough to provide a satisfactory sensation to the consumer. This paper presents an analysis to

Fredericka Brown; Kenneth R. Diller

2008-01-01

476

Hot cell facility design for large fusion devices  

SciTech Connect

Large hot cell facilities will be necessary to support the operation of large fusion devices. The supporting hot cells will be needed to serve a variety of different functions and tasks, which include reactor component maintenance, tool and maintenance equipment repair, and preparation of radioactive material for shipment and disposal. This paper discusses hot cell facility functions, requirements, and design issues and techniques. Suggested solutions and examples are given.

Barrett, R.J.; Bussell, G.T.

1985-01-01

477

HOT DEBRIS DUST AROUND HD 106797  

SciTech Connect

Photometry of the A0 V main-sequence star HD 106797 with AKARI and Gemini/T-ReCS is used to detect excess emission over the expected stellar photospheric emission between 10 and 20 {mu}m, which is best attributed to hot circumstellar debris dust surrounding the star. The temperature of the debris dust is derived as T {sub d} {approx} 190 K by assuming that the excess emission is approximated by a single temperature blackbody. The derived temperature suggests that the inner radius of the debris disk is {approx}14 AU. The fractional luminosity of the debris disk is 1000 times brighter than that of our own zodiacal cloud. The existence of such a large amount of hot dust around HD 106797 cannot be accounted for by a simple model of the steady state evolution of a debris disk due to collisions, and it is likely that transient events play a significant role. Our data also show a narrow spectral feature between 11 and 12 {mu}m attributable to crystalline silicates, suggesting that dust heating has occurred during the formation and evolution of the debris disk of HD 106797.

Fujiwara, Hideaki; Onaka, Takashi [Department of Astronomy, School of Science, University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan); Yamashita, Takuya [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Ishihara, Daisuke; Kataza, Hirokazu; Ootsubo, Takafumi; Murakami, Hiroshi; Nakagawa, Takao; Hirao, Takanori; Enya, Keigo [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510 (Japan); Fukagawa, Misato [Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka 560-0043, Osaka (Japan); Marshall, Jonathan P.; White, Glenn J. [Department of Physics and Astronomy, The Open University, Walton Hall, Milton Keynes, MK7 6AA (United Kingdom)], E-mail: fujiwara@astron.s.u-tokyo.ac.jp

2009-04-10

478

The hot plasma spectrometers on Freja  

NASA Astrophysics Data System (ADS)

The hot plasma instrumentation F3H on the Swedish-German Freja satellite due for launch in 1992 will consist of electron and ion spectrometers. The spectrometer Magnetic imaging Two dimensional Electron (MATE) will measure the two dimensional electron distribution in the spin plane in the energy range 0.1 to 120 keV. The ion mass spectrometer Three dimensional Ion Composition Spectrometer (TICS) measures a full three dimensional distribution in the energy range 0.5 to 15000 eV/q with high mass resolution. The instruments use a particle 'imaging' detector technique based on a large diameter microchannel plate with position sensitive anode. The topics to be studied with the Freja hot plasma spectrometers include auroral particle acceleration, heating and acceleration of ionospheric ions, and the dynamics of auroral arc systems. Of special importance to the scientific objectives is the high data rate from the Freja instrumentation, the MATE and TICS spectrometers will be sampled every 10 ms, corresponding to a spatial resolution better than 70 m at ionospheric heights. The design, simulation, and calibration of the spectrometers are discussed.

Norberg, O.; Eliasson, L.

1991-11-01

479

Deep drilling technology for hot crystalline rock  

SciTech Connect

The development of Hot Dry Rock (HDR) geothermal systems at the Fenton Hill, New Mexico site has required the drilling of four deep boreholes into hot, Precambrian granitic and metamorphic rocks. Thermal gradient holes, four observation wells 200 m (600 ft) deep, and an exploration core hole 800 m (2400 ft) deep guided the siting of the four deep boreholes. Results derived from the exploration core hole, GT-1 (Granite Test No. 1), were especially important in providing core from the granitic rock, and establishing the conductive thermal gradient and heat flow for the granitic basement rocks. Essential stratigraphic data and lost drilling-fluid zones were identified for the volcanic and sedimentary rocks above the contact with the crystalline basement. Using this information drilling strategies and well designs were then devised for the planning of the deeper wells. The four deep wells were drilled in pairs, the shallowest were planned and drilled to depths of 3 km in 1975 at a bottom-hole temperature of nearly 200/sup 0/C. These boreholes were followed by a pair of wells, completed in 1981, the deepest of which penetrated the Precambrian basement to a vertical depth of 4.39 km at a temperature of 320/sup 0/C.

Rowley, J.C.

1984-01-01

480

Hot Cell Window Shielding Analysis Using MCNP  

SciTech Connect

The Idaho National Laboratory Materials and Fuels Complex nuclear facilities are undergoing a documented safety analysis upgrade. In conjunction with the upgrade effort, shielding analysis of the Fuel Conditioning Facility (FCF) hot cell windows has been conducted. This paper describes the shielding analysis methodology. Each 4-ft thick window uses nine glass slabs, an oil film between the slabs, numerous steel plates, and packed lead wool. Operations in the hot cell center on used nuclear fuel (UNF) processing. Prior to the shielding analysis, shield testing with a gamma ray source was conducted, and the windows were found to be very effective gamma shields. Despite these results, because the glass contained significant amounts of lead and little neutron absorbing material, some doubt lingered regarding the effectiveness of the windows in neutron shielding situations, such as during an accidental criticality. MCNP was selected as an analysis tool because it could model complicated geometry, and it could track gamma and neutron radiation. A bounding criticality source was developed based on the composition of the UNF. Additionally, a bounding gamma source was developed based on the fission product content of the UNF. Modeling the windows required field inspections and detailed examination of drawings and material specifications. Consistent with the shield testing results, MCNP results demonstrated that the shielding was very effective with respect to gamma radiation, and in addition, the analysis demonstrated that the shielding was also very effective during an accidental criticality.

Chad L. Pope; Wade W. Scates; J. Todd Taylor

2009-05-01

481

HOT MOLECULAR CORES IN INFRARED DARK CLOUDS  

SciTech Connect

We present high angular resolution continuum images and molecular line spectra obtained at 345 GHz with the Submillimeter Array (SMA) toward two massive cores that lie within Infrared Dark Clouds (IRDCs): G034.43+00.24 MM1 and G024.33+00.11 MM1. Both of these cores contain bright, unresolved (<2'') objects that have previously been imaged in the millimeter/submillimeter continuum with the Institut de RadioAstronomie Millimetrique (IRAM) Plateau de Bure Interferometer and SMA and show complex molecular line chemistry. The new, higher angular resolution SMA continuum images reveal that both cores contain massive (8, 26 M{sub Sun }), unresolved (0.''6; {approx}3000 AU) continuum emission features and emission from many complex molecular transitions, which confirm that these are hot molecular cores, an early stage in the formation of a high-mass star. Because these hot cores are located within IRDCs, they may well represent the very earliest phases in the formation of high-mass protostars and, hence, their detailed study may reveal the initial conditions within high-mass star-forming cores, before they are shredded apart by stellar winds and radiation.

Rathborne, J. M.; Garay, G. [Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Santiago (Chile); Jackson, J. M. [Institute for Astrophysical Research, Boston University, Boston, MA 02215 (United States); Longmore, S.; Zhang, Q. [Harvard-Smithsonian Center for Astrophysics, Mail Stop 42, 60 Garden Street, Cambridge, MA 02138 (United States); Simon, R., E-mail: rathborn@das.uchile.cl, E-mail: guido@das.uchile.cl, E-mail: jackson@bu.edu, E-mail: slongmore@cfa.harvard.edu, E-mail: qzhang@cfa.harvard.edu, E-mail: simonr@ph1.uni-koeln.de [I.Physikalisches Institut, Universitaet zu Koeln, 50937 Koeln (Germany)

2011-11-10

482

Hermean Atmospheres of Hot Rocky Exoplanets  

NASA Astrophysics Data System (ADS)

The discovery of the first rocky exoplanet CoRoT-7 b suggests many stars may host rocky planets. However, with an orbital semi-major axis of only 0.0172 AU, CoRoT-7 b's dayside surface temperature probably may exceed 2000 K, and current detection biases mean that most of the initially discovered rocky exoplanets will probably be in similar orbits, with corresponding large surface temperatures. Such planets will likely have tenuous atmospheres composed of vaporized rocky material, similar to Mercury's exosphere. In fact, initial calculations suggest the atmospheres may have column abundances of volatiles, particularly sodium, exceeding the column abundance of Mercury's exosphere by many orders of magnitude. The volatiles likely present in the atmospheres of hot rocky exoplanets may be detectable through observations with sufficiently high spectral resolution. For example, at the column abundance of sodium predicted for CoRoT-7 b's exosphere, total optical depths at sodium's D1 and D2 resonant scattering features may approach 106. Consequently, the transit depth for CoRoT-7 b in the wavelengths of these features may be as much as 30% larger than out of the features. As for Mercury, detection of such an atmosphere around a hot rocky exoplanet would provide important constraints on the planet's composition. In this talk, I will present preliminary results from models of such putative atmospheres and discuss their detectability.

Jackson, Brian

2010-10-01

483

Hot-embossed polymeric optical waveguides  

NASA Astrophysics Data System (ADS)

Polymer waveguides have attracted a great deal of attention for their potential applications as optical components in optical communications, optical interconnections and optical sensors because they are easy to manufacture at a low temperature, and they have a low processing cost. Hot embossing is powerful and effective tools to produce a large volume of waveguides and structure high-precision micro/nano patterns of thin polymer films using a stamp for optical applications. In this work, fabrication techniques of hot embossed polymeric optical waveguides for parallel optical interconnection module, multi-channel variable optical attenuator and optical printed circuit boards are demonstrated. The single- and multi-mode waveguides are produced by core filling and UV curing processes. New approaches to fabricating single-mode polymeric waveguides with the high thermal stability in thermosetting polymers and two-dimensional multi-mode polymeric waveguides for high-density parallel optical interconnections as well as a simultaneous fabrication of single-mode polymeric waveguides with micro pedestals for passive fiber alignment are also reported.

Choi, Choon-Gi; Kim, Jin-Tae; Han, Sang-Pil; Ahn, Seung-Ho

2004-10-01

484

Revisiting the eccentricities of hot Jupiters  

NASA Astrophysics Data System (ADS)

Most short period transiting exoplanets have circular orbits, as expected from an estimation of the circularisation timescale using classical tidal theory. Interestingly, a small number of short period transiting exoplanets seem to have orbits with a small eccentricity. Such systems are valuable as they may indicate that some key physics is missing from formation and evolution models. We have analysed the results of a campaign of radial velocity measurements of known transiting planets with the SOPHIE and HARPS spectrographs using Bayesian methods and obtained new constraints on the orbital elements of 12 known transiting exoplanets. We also reanalysed the radial velocity data for another 42 transiting systems and show that some of the eccentric orbits reported in the Literature are compatible with a circular orbit. As a result, we show that the systems with circular and eccentric orbits are clearly separated on a plot of the planetary mass versus orbital period. We also show that planets following the trend where heavier hot Jupiters have shorter orbital periods (the ``mass-period relation'' of hot Jupiters), also tend to have circular orbits, with no confirmed exception to this rule so far.

Husnoo, Nawal; Pont, Frédéric; Mazeh, Tsevi; Fabrycky, Daniel; Hébrard, Guillaume; Moutou, Claire

2011-11-01

485

Strategic Planning for Hot Cell Closure  

SciTech Connect

The United States Department of Energy (DOE) and its contractor were remediating a large hot cell complex to mitigate the radiological hazard. A Resource Conservation and Recovery Act (RCRA) closure unit was determined to be located within the complex. The regulator established a challenge to develop an acceptable closure plan on a short schedule (four months). The scope of the plan was to remove all excess equipment and mixed waste from the closure unit, establish the requirements of the legally binding Closure Plan and develop an acceptable schedule. The complex has several highly radioactive tanks, tank vaults, piping, and large hot cells containing complex chemical processing equipment. Driven by a strong need to develop an effective strategy to meet cleanup commitments, three principles were followed to develop an acceptable plan: (1) Use a team approach, (2) Establish a buffer zone to support closure, and (3) Use good practice when planning the work sequence. The team was composed of DOE, contractor, and Washington State Department of Ecology (Regulator) staff. The team approach utilized member expertise and fostered member involvement and communication. The buffer zone established an area between the unregulated parts of the building and the areas that were allegedly not in compliance with environmental standards. Introduction of the buffer zone provided simplicity, clarity, and flexibility into the process. Using good practice means using the DOE Integrated Safety Management Core Functions for planning and implementing work safely. Paying adequate attention to detail when the situation required contributed to the process credibility and a successful plan.

LANGSTAFF, D.C.

2001-02-01

486

The hot big bang and beyond  

SciTech Connect

The hot big-bang cosmology provides a reliable accounting of the Universe from about 10{sup {minus}2} sec after the bang until the present, as well as a robust framework for speculating back to times as early as 10{sup {minus}43} sec. Cosmology faces a number of important challenges; foremost among them are determining the quantity and composition of matter in the Universe and developing a detailed and coherent picture of how structure (galaxies, clusters of galaxies, superclusters, voids, great walls, and so on) developed. At present there is a working hypothesis{emdash}cold dark matter{emdash}which is based upon inflation and which, if correct, would extend the big bang model back to 10{sup {minus}32} sec and cast important light on the unification of the forces. Many experiments and observations, from CBR anisotropy experiments to Hubble Space Telescope observations to experiments at Fermilab and CERN, are now putting the cold dark matter theory to the test. At present it appears that the theory is viable only if the Hubble constant is smaller than current measurements indicate (around 30 km s{sup {minus}1} Mpc{sup {minus}1}), or if the theory is modified slightly, e.g., by the addition of a cosmological constant, a small admixture of hot dark matter (5 eV {open_quote}{open_quote}worth of neutrinos{close_quote}{close_quote}), more relativistic particle or a tilted spectrum of density perturbations.

Turner, M.S. [Departments of Physics and of Astronomy & Astrophysics, Enrico Fermi Institute, The University of Chicago, Chicago, Illinois 60637-1433 (United States)]|[NASA/Fermilab Astrophysics Center, Fermi National Accelerator Laboratory, Batavia, Illinois 60510-0500 (United States)

1995-08-01

487

Hot spot volcanism in western North America  

NSDL National Science Digital Library

This lab project is in two parts. In the first part students are given a map of Snake River Plain volcanic centers with a range of dates of eruptions. Based on what they know about hot-spot tracks, they use the map and reported isotopic ages to calculate a range of values for the relative velocities of the North American Plate and the Yellowstone hot spot. In the second part, students are given a map of the distribution of a volcanic ash from the Yellowstone volcanic field, with thickness of the ash where known. Students are asked to contour the map to show how the ash is distributed, and think about the factors that affect that thickness, both during and after the eruption. In both parts of the lab students have to deal with real data that is incomplete in some cases, and usually occurs as a range of values. Students must make decisions about how to treat incomplete data sets that do not have absolute values.

Trexler, Jim

488

Water Temperature From Hot Water Outlets in a Major Public Hospital: How Hot is Our Water?  

PubMed Central

Objectives: To measure the water temperature issuing from a representative sample of patient-accessible outlets around the Royal Adelaide Hospital. To initiate an audit cycle in the event of unacceptably high water temperatures to ensure their reduction. Methods: Samples were taken of water issuing from hot taps, showers, and hand hygiene basins in patient areas throughout the hospital, encompassing newly renovated as well as old sections of the hospital. A 45 second “warming” period was followed by hot water collection into a polystyrene cup to 8 cm. The mean of 3 temperatures measured using an infrared thermometer was calculated. Results: Several taps and patient showers were demonstrated to supply water at a temperature capable of causing scald injuries. Most problem outlets were found in the oldest section of the hospital, fewer in the wing of “intermediate” age and none in the most recently renovated emergency block. The data were tabulated and summarized before being passed on to RAH Engineering and Building Services, which initiated remedial action. Several thermostatic mixing valves were found to be faulty (and replaced) or poorly set (and re-set). After this adjustment, outlets previously supplying excessively hot water were re-tested and found to be safe, closing the audit loop. Conclusion: Maintenance services infrequently conduct scheduled assessment of hot water outlet temperatures and rely on staff member complaints or concerns to focus their attention on problem areas. With recent evidence of the disastrous potential of hot water on a vulnerable population of hospital in-patients, hazard identification and reporting is everybody's responsibility.

Hartley, Dana; McCarthy, Ashlee; Greenwood, John E.

2011-01-01

489

The hot and cold in Mesoamerican indigenous and hispanicized thought.  

PubMed

While the influence of Hispanic humoral medicine on 16th century and subsequent Mesoamerican indigenous thought is undeniable, recent reexaminations of Aztec, Mayan and Zapotec medicinal and cosmological systems suggest indigenous roots in hot-cold concepts. This paper reviews and compares the growing evidence for independent hot-cold classifications in Mesoamerica, and suggests certain common lines of syncretism in structure, content and applications. Drawing on a model from cognitive psychology previously applied by the author to hot-cold data of the Mitla Zapotec, the paper explores its utility for cross-cultural comparison of hot-cold category development. PMID:3317874

Messer, E

1987-01-01

490

Nonlinear simulations of Jupiter's 5-micron hot spots.  

PubMed

Large-scale nonlinear simulations of Jupiter's 5-micron hot spots produce long-lived coherent structures that cause subsidence in local regions, explaining the low cloudiness and the dryness measured by the Galileo probe inside a hot spot. Like observed hot spots, the simulated coherent structures are equatorially confined, have periodic spacing, propagate west relative to the flow, are generally confined to one hemisphere, and have an anticyclonic gyre on their equatorward side. The southern edge of the simulated hot spots develops vertical shear of up to 70 meters per second in the eastward wind, which can explain the results of the Galileo probe Doppler wind experiment. PMID:10976064

Showman, A P; Dowling, T E

2000-09-01

491

Hot DQ Pulsator or Magnetic White Dwarf Binary?  

NASA Astrophysics Data System (ADS)

We present spectroscopic and photometric observations of a suspected hot carbon atmosphere (hot DQ) white dwarf which has a large-amplitude optical and ultraviolet brightness variation with a period of 84 min. Our observations show that it is not a hot DQ but instead a magnetic DA, and an observed infrared excess and periods of significantly increased luminosity suggest that it might be a polar currently in a low state. We also discuss whether the variability of the hot DQ variable stars might arise from a similar mechanism.

Dunlap, B. H.; Barlow, B. N.; Clemens, J. C.

2013-01-01

492

Radiative recombination of hot carriers in narrow-gap semiconductors  

SciTech Connect

The mechanism of the radiative recombination of hot carriers in narrow-gap semiconductors is analyzed using the example of indium antimonide. It is shown that the CHCC Auger recombination process may lead to pronounced carrier heating at high excitation levels. The distribution functions and concentrations of hot carriers are determined. The radiative recombination rate of hot carriers and the radiation gain coefficient are calculated in terms of the Kane model. It is demonstrated that the radiative recombination of hot carriers will make a substantial contribution to the total radiative recombination rate at high carrier concentrations.

Pavlov, N. V.; Zegrya, G. G., E-mail: Zegrya@theory.ioffe.ru [Russian Academy of Sciences, Ioffe Physical Technical Institute (Russian Federation)

2012-01-15

493

Diving company claims record in gulf hot tap  

SciTech Connect

This paper reports that the deepest pipeline hot tap in the U.S. Gulf of Mexico, and possibly the world, was recently accomplished in 630 ft of seawater, according to Offshore Petroleum Divers Inc. (OPD) which carried out the dive. The hot tap, in South Pass Block 50,. connected a newly constructed BP Exploration 8-in. pipeline to an operational 10-in. oil pip