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1

Penrose Well Temperatures  

SciTech Connect (OSTI)

Penrose Well Temperatures Geothermal waters have been encountered in several wells near Penrose in Fremont County, Colorado. Most of the wells were drilled for oil and gas exploration and, in a few cases, production. This ESRI point shapefile utilizes data from 95 wells in and around the Penrose area provided by the Colorado Oil and Gas Conservation Commission (COGCC) database at http://cogcc.state.co.us/ . Temperature data from the database were used to calculate a temperature gradient for each well. This information was then used to estimate temperatures at various depths. Projection: UTM Zone 13 NAD27 Extent: West -105.224871 East -105.027633 North 38.486269 South 38.259507 Originators: Colorado Oil and Gas Conservation Commission (COGCC) Karen Christopherson

Christopherson, Karen

2013-03-15T23:59:59.000Z

2

Hot Pot Contoured Temperature Gradient Map  

SciTech Connect (OSTI)

Temperature gradient contours derived from Oski temperature gradient hole program and from earlier published information.

Lane, Michael

2013-06-28T23:59:59.000Z

3

Hot Pot Contoured Temperature Gradient Map  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

Temperature gradient contours derived from Oski temperature gradient hole program and from earlier published information.

Lane, Michael

4

Pumpernickel Valley Geothermal Project Thermal Gradient Wells  

SciTech Connect (OSTI)

The Pumpernickel Valley geothermal project area is located near the eastern edge of the Sonoma Range and is positioned within the structurally complex Winnemucca fold and thrust belt of north-central Nevada. A series of approximately north-northeast-striking faults related to the Basin and Range tectonics are superimposed on the earlier structures within the project area, and are responsible for the final overall geometry and distribution of the pre-existing structural features on the property. Two of these faults, the Pumpernickel Valley fault and Edna Mountain fault, are range-bounding and display numerous characteristics typical of strike-slip fault systems. These characteristics, when combined with geophysical data from Shore (2005), indicate the presence of a pull-apart basin, formed within the releasing bend of the Pumpernickel Valley – Edna Mountain fault system. A substantial body of evidence exists, in the form of available geothermal, geological and geophysical information, to suggest that the property and the pull-apart basin host a structurally controlled, extensive geothermal field. The most evident manifestations of the geothermal activity in the valley are two areas with hot springs, seepages, and wet ground/vegetation anomalies near the Pumpernickel Valley fault, which indicate that the fault focuses the fluid up-flow. There has not been any geothermal production from the Pumpernickel Valley area, but it was the focus of a limited exploration effort by Magma Power Company. In 1974, the company drilled one exploration/temperature gradient borehole east of the Pumpernickel Valley fault and recorded a thermal gradient of 160oC/km. The 1982 temperature data from five unrelated mineral exploration holes to the north of the Magma well indicated geothermal gradients in a range from 66 to 249oC/km for wells west of the fault, and ~283oC/km in a well next to the fault. In 2005, Nevada Geothermal Power Company drilled four geothermal gradient wells, PVTG-1, -2, -3, and -4, and all four encountered geothermal fluids. The holes provided valuable water geochemistry, supporting the geothermometry results obtained from the hot springs and Magma well. The temperature data gathered from all the wells clearly indicates the presence of a major plume of thermal water centered on the Pumpernickel Valley fault, and suggests that the main plume is controlled, at least in part, by flow from this fault system. The temperature data also defines the geothermal resource with gradients >100oC/km, which covers an area a minimum of 8 km2. Structural blocks, down dropped with respect to the Pumpernickel Valley fault, may define an immediate reservoir. The geothermal system almost certainly continues beyond the recently drilled holes and might be open to the east and south, whereas the heat source responsible for the temperatures associated with this plume has not been intersected and must be at a depth greater than 920 meters (depth of the deepest well – Magma well). The geological and structural setting and other characteristics of the Pumpernickel Valley geothermal project area are markedly similar to the portions of the nearby Dixie Valley geothermal field. These similarities include, among others, the numerous, unexposed en echelon faults and large-scale pull-apart structure, which in Dixie Valley may host part of the geothermal field. The Pumpernickel Valley project area, for the majority of which Nevada Geothermal Power Company has geothermal rights, represents a geothermal site with a potential for the discovery of a relatively high temperature reservoir suitable for electric power production. Among locations not previously identified as having high geothermal potential, Pumpernickel Valley has been ranked as one of four sites with the highest potential for electrical power production in Nevada (Shevenell and Garside, 2003). Richards and Blackwell (2002) estimated the total heat loss and the preliminary production capacity for the entire Pumpernickel Valley geothermal system to be at 35MW. A more conservative estimate, for

Z. Adam Szybinski

2006-01-01T23:59:59.000Z

5

Ballistic dispersion in temperature gradient focusing  

E-Print Network [OSTI]

regime is the most familiar regime in microfluidic systems, an oft-overlooked regime is that of purely kinematic (or ballistic) dispersion. In most microfluidic systems, this dispersion regime is transient systems. Keywords: microfluidics; temperature gradient focusing; kinematic dispersion; Taylor

Santiago, Juan G.

6

Short wavelength ion temperature gradient turbulence  

SciTech Connect (OSTI)

The ion temperature gradient (ITG) mode in the high wavenumber regime (k{sub y}{rho}{sub s}>1), referred to as short wavelength ion temperature gradient mode (SWITG) is studied using the nonlinear gyrokinetic electromagnetic code GENE. It is shown that, although the SWITG mode may be linearly more unstable than the standard long wavelength (k{sub y}{rho}{sub s}<1) ITG mode, nonlinearly its contribution to the total thermal ion heat transport is found to be low. We interpret this as resulting from an increased zonal flow shearing effect on the SWITG mode suppression.

Chowdhury, J.; Ganesh, R. [Institute for Plasma Research, Bhat, Gandhinagar (India); Brunner, S.; Lapillonne, X.; Villard, L. [CRPP, Association EURATOM-Confederation Suisse, EPFL, 1015 Lausanne (Switzerland); Jenko, F. [Max-Planck-Institut fuer Plasmaphysik Boltzmannstr. 2, D-85748 Garching (Germany)

2012-10-15T23:59:59.000Z

7

Bayesian Learning via Stochastic Gradient Langevin Dynamics Max Welling welling@ics.uci.edu  

E-Print Network [OSTI]

Bayesian Learning via Stochastic Gradient Langevin Dynamics Max Welling welling@ics.uci.edu D. Bren on iterative learning from small mini-batches. By adding the right amount of noise to a standard stochastic" and collects sam- ples after it has been surpassed. We apply the method to three models: a mixture of Gaussians

Kaski, Samuel

8

Thermal Gradient Holes At Salt Wells Area (Bureau of Land Management...  

Open Energy Info (EERE)

Salt Wells Area (Bureau of Land Management, 2009) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Salt Wells Area...

9

Measurements of aerosol thermophoretic deposition: Transition with temperature gradient  

SciTech Connect (OSTI)

Thermophoresis is the motion of aerosol particles due to a temperature gradient in the suspending gas. The thermophoretic velocity V{sub T} is expressed as: where a {alpha} = thermal diffusivity v = kinematic viscosity H= Pr K Pr = Prandtl number K = dimensionless coefficient that is a function of several parameters (particle radius, thermal conductivity, gas properties, gas surface interactions). This report describes measurements of the effects of temperature gradients on the deposition of polystyrene latex particles.

Varma, A.; Tompson, R.V.; Loyalka, S.K. [Univ. of Missouri, Columbia, MO (United States)

1995-12-31T23:59:59.000Z

10

Manipulation of Colloids by Nonequilibrium Depletion Force in Temperature Gradient  

E-Print Network [OSTI]

The non-equilibrium distribution of colloids in a polymer solution under a temperature gradient is studied experimentally. A slight increase of local temperature by a focused laser drives the colloids towards the hot region, resulting in the trapping of the colloids irrespective of their own thermophoretic properties. An amplification of the trapped colloid density with the polymer concentration is measured, and is quantitatively explained by hydrodynamic theory. The origin of the attraction is a migration of colloids driven by a non-uniform polymer distribution sustained by the polymer's thermophoresis. These results show how to control thermophoretic properties of colloids.

Hong-Ren Jiang; Hirofumi Wada; Natsuhiko Yoshinaga; Masaki Sano

2009-04-22T23:59:59.000Z

11

Formation of Complex Structures in Dusty Plasmas under Temperature Gradients  

SciTech Connect (OSTI)

Thermophoretic effects on dust structures under temperature gradients in glow and radio-frequency discharge plasmas are studied experimentally. The geometry of dust structures consisting of micrometer-sized polydisperse grains depends on heat release in the plasma. Thermophoretic forces associated with heat release can control the formation of dust structures of different geometries. A theoretical model is proposed to describe dust separation with respect to grain size caused by the effects of radial electrostatic and thermophoretic forces. The glow discharge currents under critical conditions for grain separation predicted by the model agree with those observed experimentally.

Vasilyak, L.M.; Vetchinin, S.P.; Polyakov, D.N.; Fortov, V.E. [Institute for High Energy Densities, Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow, 125412 (Russian Federation)

2005-05-01T23:59:59.000Z

12

Electron geodesic acoustic modes in electron temperature gradient mode turbulence  

SciTech Connect (OSTI)

In this work, the first demonstration of an electron branch of the geodesic acoustic mode (el-GAM) driven by electron temperature gradient (ETG) modes is presented. The work is based on a fluid description of the ETG mode retaining non-adiabatic ions and the dispersion relation for el-GAMs driven nonlinearly by ETG modes is derived. A new saturation mechanism for ETG turbulence through the interaction with el-GAMs is found, resulting in a significantly enhanced ETG turbulence saturation level compared to the mixing length estimate.

Anderson, Johan; Nordman, Hans [Department of Earth and Space Sciences, Chalmers University of Technology, SE-412 96 Goeteborg (Sweden); Singh, Raghvendra; Kaw, Predhiman [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428 (India)

2012-08-15T23:59:59.000Z

13

Pagosa Springs Private Wells Space Heating Low Temperature Geothermal...  

Open Energy Info (EERE)

Private Wells Space Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Pagosa Springs Private Wells Space Heating Low Temperature Geothermal Facility...

14

Effects of Temperature Gradients and Heat Fluxes on High-Temperature Oxidation  

SciTech Connect (OSTI)

The effects of a temperature gradient and heat flux on point defect diffusion in protective oxide scales were examined. Irreversible thermodynamics were used to expand Fick’s first law of diffusion to include a heat-flux term—a Soret effect. Oxidation kinetics were developed for the oxidation of cobalt and of nickel doped with chromium. Research is described to verify the effects of a heat flux by oxidizing pure cobalt in a temperature gradient at 900 °C, and comparing the kinetics to isothermal oxidation. No evidence of a heat flux effect was found.

Holcomb, G.R.

2008-04-01T23:59:59.000Z

15

Lithologic descriptions and temperature profiles of five wells in the southwestern Valles caldera region, New Mexico  

SciTech Connect (OSTI)

The subsurface stratigraphy and temperature profiles of the southern and western Valles caldera region have been well constrained with the use of data from the VC-1, AET-4, WC 23-4, PC-1 and PC-2 wells. Data from these wells indicate that thermal gradients west of the caldera margin are between 110 and 140)degrees)C/km, with a maximum gradient occurring in the bottom of PC-1 equal to 240)degrees)C/km as a result of thermal fluid flow. Gradients within the caldera reach a maximum of 350)degrees)C/km, while the maximum thermal gradient measured southwest of the caldera in the thermal outflow plume is 140)degrees)C/km. The five wells exhibit high thermal gradients (>60)deghrees)C/km) resulting from high conductive heat flow associated with the Rio Grande rift and volcanism in the Valles caldera, as well as high convective heat flow associated with circulating geothermal fluids. Gamma logs run in four of the five wells appear to be of limited use for stratigraphic correlations in the caldera region. However, stratigraphic and temperature data from the five wells provide information about the structure and thermal regime of the southern and western Valles caldera region. 29 refs., 9 figs. 2 tabs.

Shevenell, L.; Goff, F.; Miles, D.; Waibel, A.; Swanberg, C.

1988-01-01T23:59:59.000Z

16

Coherent structures in ion temperature gradient turbulence-zonal flow  

SciTech Connect (OSTI)

Nonlinear stationary structure formation in the coupled ion temperature gradient (ITG)-zonal flow system is investigated. The ITG turbulence is described by a wave-kinetic equation for the action density of the ITG mode, and the longer scale zonal mode is described by a dynamic equation for the m?=?n?=?0 component of the potential. Two populations of trapped and untrapped drift wave trajectories are shown to exist in a moving frame of reference. This novel effect leads to the formation of nonlinear stationary structures. It is shown that the ITG turbulence can self-consistently sustain coherent, radially propagating modulation envelope structures such as solitons, shocks, and nonlinear wave trains.

Singh, Rameswar, E-mail: rameswar.singh@lpp.polytechnique.fr [Laboratoire de Physique des Plasmas, Ecole Polytechnique, Route de Saclay, 91128 Palaiseau Cedex (France); Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); Singh, R. [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Kaw, P. [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); Gürcan, Ö. D. [Laboratoire de Physique des Plasmas, Ecole Polytechnique, Route de Saclay, 91128 Palaiseau Cedex (France); Diamond, P. H. [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); CMTFO and CASS, University of California, San Diego, California 92093 (United States)

2014-10-15T23:59:59.000Z

17

Ion temperature gradient driven turbulence with strong trapped ion resonance  

SciTech Connect (OSTI)

A theory to describe basic characterization of ion temperature gradient driven turbulence with strong trapped ion resonance is presented. The role of trapped ion granulations, clusters of trapped ions correlated by precession resonance, is the focus. Microscopically, the presence of trapped ion granulations leads to a sharp (logarithmic) divergence of two point phase space density correlation at small scales. Macroscopically, trapped ion granulations excite potential fluctuations that do not satisfy dispersion relation and so broaden frequency spectrum. The line width from emission due only to trapped ion granulations is calculated. The result shows that the line width depends on ion free energy and electron dissipation, which implies that non-adiabatic electrons are essential to recover non-trivial dynamics of trapped ion granulations. Relevant testable predictions are summarized.

Kosuga, Y., E-mail: kosuga@riam.kyushu-u.ac.jp [Institute for Advanced Study, Kyushu University, Fukuoka (Japan); Research Institute for Applied Mechanics, Kyushu University, Fukuoka (Japan); Itoh, S.-I. [Research Center for Plasma Turbulence, Kyushu University, Fukuoka (Japan); Research Institute for Applied Mechanics, Kyushu University, Fukuoka (Japan); Diamond, P. H. [CASS and CMTFO, University of California at San Diego, La Jolla, California 92093 (United States); WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon (Korea, Republic of); Itoh, K. [National Institute for Fusion Science, Gifu (Japan); Research Center for Plasma Turbulence, Kyushu University, Fukuoka (Japan); Lesur, M. [Research Institute for Applied Mechanics, Kyushu University, Fukuoka (Japan)

2014-10-15T23:59:59.000Z

18

Geology and Temperature Gradient Surveys Blue Mountain Geothermal...  

Open Energy Info (EERE)

Gradient Surveys Blue Mountain Geothermal Discovery, Humboldt County, Nevada Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Geology and...

19

Calcite Mineral Scaling Potentials of High-Temperature Geothermal Wells  

E-Print Network [OSTI]

#12;i Calcite Mineral Scaling Potentials of High-Temperature Geothermal Wells Alvin I. Remoroza-Temperature Geothermal Wells Alvin I. Remoroza 60 ECTS thesis submitted in partial fulfillment of a Magister Scientiarum #12;iv Calcite Mineral Scaling Potentials of High-Temperature Geothermal Wells 60 ECTS thesis

Karlsson, Brynjar

20

Supercurrent-Induced Temperature Gradient across a Nonequilibrium SNS Josephson Junction M. S. Crosser,1  

E-Print Network [OSTI]

Supercurrent-Induced Temperature Gradient across a Nonequilibrium SNS Josephson Junction M. S direction. The feature represents an effective temperature gradient across the SNS Josephson junction Josephson junction (SNS JJ) into a `` junction'' by driving the electron energy distribution far from

Birge, Norman

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Temperature behavior in the build section of multilateral wells  

E-Print Network [OSTI]

. The model predicts the temperature profiles in the build sections connecting the laterals to one another or to a main wellbore, thus accounting for the changing well angle relative to the temperature profile in the earth. In addition, energy balance...

Romero Lugo, Analis Alejandra

2005-11-01T23:59:59.000Z

22

On the maintenance of weak meridional temperature gradients during warm climates  

E-Print Network [OSTI]

This thesis examines the dynamics of equable climates. The underlying physics of two mechanisms by which weak meridional temperature gradients might be maintained are studied. First, I examine the evolution of stratospheric ...

Korty, Robert Lindsay

2005-01-01T23:59:59.000Z

23

Interpreting Horizontal Well Flow Profiles and Optimizing Well Performance by Downhole Temperature and Pressure Data  

E-Print Network [OSTI]

be used to obtain downhole flow conditions, which is key information to control and optimize horizontal well production. However, the fluid flow in the reservoir is often multiphase and complex, which makes temperature and pressure interpretation very...

Li, Zhuoyi

2011-02-22T23:59:59.000Z

24

Results of temperature gradient and heat flow in Santiam Pass Area, Oregon, Volume 1  

SciTech Connect (OSTI)

The conclusions of this report are: (1) There is a weakly defined thermal anomaly within the area examined by temperature-gradient holes in the Santiam Pass area. This is a relict anomaly showing differences in permeability between the High Cascades and Western Cascades areas, more than a fundamental difference in shallow crustal temperatures. (2) The anomaly as defined by the 60 F isotherms at 400 feet follows a north-south trend immediately westward of the Cascade axis in the boundary region. It is clear that all holes spudded into High Cascades rocks result in isothermal and reversal gradients. Holes spudded in Western Cascades rocks result in positive gradients. (3) Cold groundwater flow influences and masks temperature gradients in the High Cascades to a depth of at least 700 feet, especially eastward from the major north-south trending faults. Pleistocene and Holocene rocks are very permeable aquifers. (4) Shallow gradient drilling in the lowlands westward of the faults provides more interpretable information than shallow drilling in the cold-water recharge zones. Topographic and climatological effects can be filtered out of the temperature gradient results. (5) The thermal anomaly seems to have 2 centers: one in the Belknap-Foley area, and one northward in the Sand Mountain area. The anomalies may or may not be connected along a north-south trend. (6) A geothermal effect is seen in holes downslope of the Western-High Cascade boundary. Mixing with cold waters is a powerful influence on temperature gradient data. (7) The temperature-gradient program has not yet examined and defined the geothermal resources potential of the area eastward of the Western Cascades-High Cascades boundary. Holes to 1500-2000 feet in depth are required to penetrate the high permeability-cold groundwater regime. (8) Drilling conditions are unfavorable. There are very few accessible level drill sites. Seasonal access problems and environmental restrictions together with frequent lost circulation results in very high costs per foot drilled.

Cox, B.L.; Gardner, M.C.; Koenig, J.B.

1981-08-01T23:59:59.000Z

25

Mirror symmetry breaking with limited enantioselective autocatalysis and temperature gradients: a stability survey  

E-Print Network [OSTI]

We analyze limited enantioselective (LES) autocatalysis in a temperature gradient and with internal flow/recycling of hot and cold material. Microreversibility forbids broken mirror symmetry for LES in the presence of a temperature gradient alone. This symmetry can be broken however when the auto-catalysis and limited enantioselective catalysis are each localized within the regions of low and high temperature, respectively. This scheme has been recently proposed as a plausible model for spontaneous emergence of chirality in abyssal hydrothermal vents. Regions in chemical parameter space are mapped out in which the racemic state is unstable and bifurcates to chiral solutions.

Blanco, Celia; Crusats, Joaquim; El-Hachemi, Zoubir; Moyano, Albert; Hochberg, David; 10.1039/C2CP43488A

2012-01-01T23:59:59.000Z

26

Probing plasma turbulence by modulating the electron temperature gradient  

E-Print Network [OSTI]

The local value of a/L[subscript Te], a turbulence drive term, was modulated with electron cyclotron heating in L-mode discharges on DIII-D [ J. L. Luxon, Nucl. Fusion 42, 614 (2002) ] and the density and electron temperature ...

DeBoo, J. C.

27

Finite ballooning angle effects on ion temperature gradient driven mode in gyrokinetic flux tube simulations  

SciTech Connect (OSTI)

This paper presents effects of finite ballooning angles on linear ion temperature gradient (ITG) driven mode and associated heat and momentum flux in Gyrokinetic flux tube simulation GENE. It is found that zero ballooning angle is not always the one at which the linear growth rate is maximum. The ITG mode acquires a short wavelength (SW) branch (k{sub ?}?{sub i}?>?1) when growth rates maximized over all ballooning angles are considered. However, the SW branch disappears on reducing temperature gradient showing characteristics of zero ballooning angle SWITG in case of extremely high temperature gradient. Associated heat flux is even with respect to ballooning angle and maximizes at nonzero ballooning angle while the parallel momentum flux is odd with respect to the ballooning angle.

Singh, Rameswar, E-mail: rameswar.singh@lpp.polytechnique.fr [Institute for Plasma Research, Bhat Gandhinagar, Gujarat 2382 428 (India) [Institute for Plasma Research, Bhat Gandhinagar, Gujarat 2382 428 (India); Laboratoire de Physique des Plasmas, Ecole Polytechnique, Route de Saclay, 91128 Palaiseau Cedex (France); Brunner, S. [CRPP, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne (Switzerland)] [CRPP, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne (Switzerland); Ganesh, R. [Institute for Plasma Research, Bhat Gandhinagar, Gujarat 2382 428 (India)] [Institute for Plasma Research, Bhat Gandhinagar, Gujarat 2382 428 (India); Jenko, F. [Max-Planck-Institut fur Plasmaphysik, EURATOM Association, D-85748 Garching (Germany)] [Max-Planck-Institut fur Plasmaphysik, EURATOM Association, D-85748 Garching (Germany)

2014-03-15T23:59:59.000Z

28

Phenotypic Plasticity of Leaf Shape along a Temperature Gradient in Acer rubrum  

E-Print Network [OSTI]

Phenotypic Plasticity of Leaf Shape along a Temperature Gradient in Acer rubrum Dana L. Royer1 plasticity and genetic determination can be important for understanding how plants respond to environmental change. However, little is known about the plastic response of leaf teeth and leaf dissection

Royer, Dana

29

Water transport inside a single-walled carbon nanotube driven by temperature gradient  

E-Print Network [OSTI]

Water transport inside a single-walled carbon nanotube driven by temperature gradient J. Shiomi mass transport of a water cluster inside a single-walled carbon nanotube (SWNT) with the diameter of about 1.4 nm. The influence of the non-equilibrium thermal environment on the confined water cluster has

Maruyama, Shigeo

30

Electron velocity distribution function in a plasma with temperature gradient and in the presence of suprathermal  

E-Print Network [OSTI]

Electron velocity distribution function in a plasma with temperature gradient and in the presence of suprathermal electrons: application to incoherent-scatter plasma lines P. Guio1 , J. Lilensten2 , W. Kofman2 arbitrary velocity distribution function with cylindrical symmetry along the magnetic ®eld. The electron

Paris-Sud XI, Université de

31

Effect of Temperature Gradient on Industrial Coal Slag Infiltration into Porous Refractory Materials in Slagging Gasifiers  

SciTech Connect (OSTI)

Infiltration characteristics of industrial coal slag into alumina (Al{sub 2}O{sub 3}) refractory material with a temperature gradient induced along the slag's penetration direction are compared to those obtained under near-isothermal conditions. Experiments were conducted with a hot-face temperature of 1450°C and a CO/CO{sub 2} ratio of 1.8, which corresponds to an oxygen partial pressure of ~10{sup ?8} atm. The refractory under the near-isothermal temperature profile, with higher average temperatures, demonstrated a greater penetration depth than its counterpart that was under the steeper temperature gradient. Slag that did not infiltrate into the refractory due to the induced temperature gradient, pooled and solidified on the top of the sample. Within the pool, a conglomerated mass of troilite (FeS) formed separately from the surrounding slag. Microscopy of the cross-sectioned infiltrated refractories revealed that the slag preferentially corroded the matrix regions closer to the top surface. Furthermore, the formation of a thick layer of hercynite (FeAl{sub 2}O{sub 4}) at the top of refractory/slag interface significantly depleted the slag of its iron-oxide content with respect to its virgin composition. A qualitative description of the penetration process is provided in this article.

Kaneko, Tetsuya Kenneth; Bennett, James P.; Dridhar, Seetharaman

2011-12-01T23:59:59.000Z

32

The Temperature Prediction in Deepwater Drilling of Vertical Well  

E-Print Network [OSTI]

.................................................................................................. 30 3.4 Geothermal Gradient ................................................................................ 30 3.5 Overall Heat Transfer Coefficient ............................................................ 30... ............................................................................................ 47 vii ? Page 5.2 Conservation Of Energy ........................................................................... 47 5.3 Steady-state Heat Transfer Model...

Feng, Ming

2012-07-16T23:59:59.000Z

33

The 1983 Temperature Gradient and Heat Flow Drilling Project for the State of Washington  

SciTech Connect (OSTI)

During the Summer of 1983, the Washington Division of Geology and Earth Resources carried out a three-hole drilling program to collect temperature gradient and heat flow information near potential geothermal resource target areas. The project was part of the state-coupled US Department of Energy Geothermal Program. Richardson Well Drilling of Tacoma, Washington was subcontracted through the State to perform the work. The general locations of the project areas are shown in figure 1. The first hole, DNR 83-1, was located within the Green River valley northwest of Mount St. Helens. This site is near the Green River Soda Springs and along the projection of the Mount St. Helens--Elk Lake seismic zone. The other two holes were drilled near Mount Baker. Hole DNR 83-3 was sited about 1/4 km west of the Baker Hot Springs, 10.5 km east of Mount Baker, while hole DNR 83-5 was located along Rocky Creek in the Sulphur Creek Valley. The Rocky Creek hole is about 10 km south-southwest of the peak. Two other holes, DNR 83-2 and DNR 83-4, were located on the north side of the Sulphur Creek Valley. Both holes were abandoned at early stages of drilling because of deep overburden and severe caving problems. The sites were apparently located atop old landslide deposits.

Korosec, Michael A.

1983-11-01T23:59:59.000Z

34

Measurements of Electron Thermal Transport due to Electron Temperature Gradient Modes in a Basic Experiment  

SciTech Connect (OSTI)

Production and identification of electron temperature gradient modes have already been reported [X. Wei, V. Sokolov, and A. K. Sen, Phys. Plasmas 17, 042108 (2010)]. Now a measurement of electron thermal conductivity via a unique high frequency triple probe yielded a value of {chi}{sub perpendiculare} ranging between 2 and 10 m{sup 2}/s, which is of the order of a several gyrobohm diffusion coefficient. This experimental result appears to agree with a value of nonlocal thermal conductivity obtained from a rough theoretical estimation and not inconsistent with gyrokinetic simulation results for tokamaks. The first experimental scaling of the thermal conductivity versus the amplitude of the electron temperature gradient fluctuation is also obtained. It is approximately linear, indicating a strong turbulence signature.

Sokolov, V.; Sen, A. K. [Plasma Research Laboratory, Columbia University, New York, New York 10027 (United States)

2011-10-07T23:59:59.000Z

35

Gyrokinetic and Gyrofluid Models for Zonal Flow Dynamics in Ion and Electron Temperature Gradient Turbulence  

SciTech Connect (OSTI)

Collisionless time evolution of zonal flows in ion and electron temperature gradient turbulence in toroidal plasmas is investigated. The responses of the zonal-flow potential to the initial perturbation and to the turbulence source are determined from the gyrokinetic equations combined with the Poisson equation, A novel gyrofluid model is presented, which properly describes the zonal-flow time evolution and reproduces the same residual zonal-flow levels as predicted by the gyrokinetic model.

Sugama, H.; Watanabe, T.-H. [National Institute for Fusion Science, Toki, Gifu, 509-5292 (Japan); Graduate University for Advanced Studies, Toki, Gifu, 509-5292 (Japan); Ferrando i Margalet, S. [National Institute for Fusion Science, Toki, Gifu, 509-5292 (Japan)

2006-11-30T23:59:59.000Z

36

A study of self organized criticality in ion temperature gradient mode driven gyrokinetic turbulence  

SciTech Connect (OSTI)

An investigation on the characteristics of self organized criticality (Soc) in ITG mode driven turbulence is made, with the use of various statistical tools (histograms, power spectra, Hurst exponents estimated with the rescaled range analysis, and the structure function method). For this purpose, local non-linear gyrokinetic simulations of the cyclone base case scenario are performed with the GENE software package. Although most authors concentrate on global simulations, which seem to be a better choice for such an investigation, we use local simulations in an attempt to study the locally underlying mechanisms of Soc. We also study the structural properties of radially extended structures, with several tools (fractal dimension estimate, cluster analysis, and two dimensional autocorrelation function), in order to explore whether they can be characterized as avalanches. We find that, for large enough driving temperature gradients, the local simulations exhibit most of the features of Soc, with the exception of the probability distribution of observables, which show a tail, yet they are not of power-law form. The radial structures have the same radial extent at all temperature gradients examined; radial motion (transport) though appears only at large temperature gradients, in which case the radial structures can be interpreted as avalanches.

Mavridis, M.; Isliker, H.; Vlahos, L. [Section of Astrophysics, Astronomy and Mechanics, Department of Physics, Aristotle University of Thessaloniki, GR-54124 Thessaloniki (Greece); Görler, T.; Jenko, F.; Told, D. [Max Planck Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany)

2014-10-15T23:59:59.000Z

37

Stability threshold of ion temperature gradient driven mode in reversed field pinch plasmas  

SciTech Connect (OSTI)

For the first time in the reversed field pinch (RFP) configuration, the stability threshold of the ion temperature gradient driven (ITG) mode is studied by linear gyrokinetic theory. In comparison with tokamaks, the RFP configuration has a shorter connection length and stronger magnetic curvature drift. These effects result in a stronger instability driving mechanism and a larger growth rate in the fluid limit. However, the kinetic theory shows that the temperature slopes required for the excitation of ITG instability are much steeper than the tokamak ones. This is because the effect of Landau damping also becomes stronger due to the shorter connection length, which is dominant and ultimately determines the stability threshold. The required temperature slope for the instability may only be found in the very edge of the plasma and/or near the border of the dominant magnetic island during the quasi-single helicity state of discharge.

Guo, S. C. [Consorzio RFX, Associazione Euratom-ENEA sulla fusione, Corso Stati Uniti 4, Padova 35127 (Italy)

2008-12-15T23:59:59.000Z

38

Vertical distribution of larval stages of the horn fly, Haematobia irritans irritans (L.), in relation to manure pat temperature gradients  

E-Print Network [OSTI]

VERTICAL DISTRISUTION OF LARVAL STAGES OF THE HORN FLY, HAEMATOBIA IRRITANS IRRITANS (L. ), IN RELATION TO MANURE PAT TEMPERATURE GRADIENTS A Thesis by PHILIP ANDERSON MARCH Submitted to the Graduate College of Texas AijM University... in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE May 1981 Major Subject: Entomology VERTICAL DISTRIBUTION OF LARVAL STAGES OF THE HORN FLY, HAEMATOBIA IRRITANS IRRITANS (L. ), IN RELATION TO MANURE PAT TEMPERATURE GRADIENTS...

March, Philip Anderson

1981-01-01T23:59:59.000Z

39

Comparison of analytical models for zonal flow generation in ion-temperature-gradient mode turbulence  

SciTech Connect (OSTI)

During the past years the understanding of the multi scale interaction problems have increased significantly. However, at present there exists a flora of different analytical models for investigating multi scale interactions and hardly any specific comparisons have been performed among these models. In this work two different models for the generation of zonal flows from ion-temperature-gradient (ITG) background turbulence are discussed and compared. The methods used are the coherent mode coupling model and the wave kinetic equation model (WKE). It is shown that the two models give qualitatively the same results even though the assumption on the spectral difference is used in the (WKE) approach.

Anderson, J.; Miki, K.; Uzawa, K.; Li, J.; Kishimoto, Y. [Dept. Fundamental Energy Science, School of Energy Science, Kyoto University, Gokasho, Uji, Kyoto, 611-0011 (Japan)

2006-11-30T23:59:59.000Z

40

Gyrokinetic-Vlasov simulations of the ion temperature gradient turbulence in tokamak and helical systems  

SciTech Connect (OSTI)

Recent progress of the gyrokinetic-Vlasov simulations on the ion temperature gradient (ITG) turbulence in tokamak and helical systems is reported, where the entropy balance is checked as a reference for the numerical accuracy. The tokamak ITG turbulence simulation carried out on the Earth Simulator clearly captures a nonlinear generation process of zonal flows. The tera-flops and tera-bytes scale simulation is also applied to a helical system with the same poloidal and toroidal periodicities of L = 2 and M = 10 as in the Large Helical Device.

Watanabe, T.-H.; Sugama, H. [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan); Graduate University for Advanced Studies (Sokendai), Toki, Gifu 509-5292 (Japan); Ferrando i Margalet, S. [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan)

2006-11-30T23:59:59.000Z

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Turbulent electron transport in edge pedestal by electron temperature gradient turbulence  

SciTech Connect (OSTI)

We present a model for turbulent electron thermal transport at the edge pedestal in high (H)-mode plasmas based on electron temperature gradient (ETG) turbulence. A quasi-linear analysis of electrostatic toroidal ETG modes shows that both turbulent electron thermal diffusivity and hyper-resistivity exhibits the Ohkawa scaling in which the radial correlation length of turbulence becomes the order of electron skin depth. Combination of the Ohkawa scales and the plasma current dependence results in a novel confinement scaling inside the pedestal region. It is also shown that ETG turbulence induces a thermoelectric pinch, which may accelerate the density pedestal formation.

Singh, R. [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of) [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Institute for Plasma Research, Bhat Gandhinagar, Gujarat 2382 428 (India); Jhang, Hogun [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of)] [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Diamond, P. H. [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of) [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); CMTFO and CASS, University of California, San Diego 92093-0424, California (United States)

2013-11-15T23:59:59.000Z

42

Fine-Scale Zonal Flow Suppression of Electron Temperature Gradient Turbulence  

SciTech Connect (OSTI)

It is found in collisionless Electron Temperature Gradient (ETG) turbulence simulations that, while zonal flows are weak at early times, the zonal flows continue to grow algebraically (proportional to time). These fine-scale zonal flows have a radial wave number such that kr{rho}i > 1 and kr{rho}e < 1. Eventually, the zonal flows grow to a level that suppresses the turbulence due to ExB shearing. The final electron energy flux is found to be relatively low. These conclusions are based on particle convergence studies with adiabatic ion electrostatic flux-tube gyrokinetic {delta}f particle simulations run for long times. The Rosenbluth-Hinton random walk mechanism is given as an explanation for the long time build up of the zonal flow in ETG turbulence and it is shown that the generation is (k perpendicular {rho}e)2 smaller than for isomorphic Ion Temperature Gradient (ITG) problem. This mechanism for zonal flow generation here is different than the modulational instability mechanism for ITG turbulence. These results are important because previous results indicated zonal flows were unimportant for ETG turbulence. Weak collisional damping of the zonal flow is also shown to be a n important effect.

Parker, S. E.; Kohut, J. J.; Chen, Y. [Center for Integrated Plasma Studies, University of Colorado, Boulder, C0 (United States); Lin, Z. [University of Californian, Irvine, CA (United States); Hinton, F. L. [Hinton Associates, Escondido, CA (United States); Lee, W. W. [Princeton Plasma Physics Laboratory, Princeton, NJ (United States)

2006-11-30T23:59:59.000Z

43

Grain-scale thermoelastic stresses and spatiotemporal temperature gradients on airless bodies, implications for rock breakdown  

E-Print Network [OSTI]

Thermomechanical processes such as fatigue and shock have been suggested to cause and contribute to rock breakdown on Earth, and on other planetary bodies, particularly airless bodies in the inner solar system. In this study, we modeled grain-scale stresses induced by diurnal temperature variations on simple microstructures made of pyroxene and plagioclase on various solar system bodies. We found that a heterogeneous microstructure on the Moon experiences peak tensile stresses on the order of 100 MPa. The stresses induced are controlled by the coefficient of thermal expansion and Young's modulus of the mineral constituents, and the average stress within the microstructure is determined by relative volume of each mineral. Amplification of stresses occurs at surface-parallel boundaries between adjacent mineral grains and at the tips of pore spaces. We also found that microscopic spatial and temporal surface temperature gradients do not correlate with high stresses, making them inappropriate proxies for investig...

Molaro, Jamie L; Langer, Steve A

2015-01-01T23:59:59.000Z

44

Ion-temperature-gradient sensitivity of the hydrodynamic instability caused by shear in the magnetic-field-aligned plasma flow  

SciTech Connect (OSTI)

The cross-magnetic-field (i.e., perpendicular) profile of ion temperature and the perpendicular profile of the magnetic-field-aligned (parallel) plasma flow are sometimes inhomogeneous for space and laboratory plasma. Instability caused either by a gradient in the ion-temperature profile or by shear in the parallel flow has been discussed extensively in the literature. In this paper, (1) hydrodynamic plasma stability is investigated, (2) real and imaginary frequency are quantified over a range of the shear parameter, the normalized wavenumber, and the ratio of density-gradient and ion-temperature-gradient scale lengths, and (3) the role of inverse Landau damping is illustrated for the case of combined ion-temperature gradient and parallel-flow shear. We find that increasing the ion-temperature gradient reduces the instability threshold for the hydrodynamic parallel-flow shear instability, also known as the parallel Kelvin-Helmholtz instability or the D'Angelo instability. We also find that a kinetic instability arises from the coupled, reinforcing action of both free-energy sources. For the case of comparable electron and ion temperature, we illustrate analytically the transition of the D'Angelo instability to the kinetic instability as (a) the shear parameter, (b) the normalized wavenumber, and (c) the ratio of density-gradient and ion-temperature-gradient scale lengths are varied and we attribute the changes in stability to changes in the amount of inverse ion Landau damping. We show that near a normalized wavenumber k{sub ?}?{sub i} of order unity (i) the real and imaginary values of frequency become comparable and (ii) the imaginary frequency, i.e., the growth rate, peaks.

Mikhailenko, V. V., E-mail: vladimir@pusan.ac.kr [Plasma Research Center, Pusan National University, Busan 609-735 (Korea, Republic of); Mikhailenko, V. S. [School of Physics and Technology, V.N. Karazin Kharkiv National University, 61108 Kharkiv (Ukraine); Faculty of Transportation Systems, Kharkiv National Automobile and Highway University, 61002 Kharkiv (Ukraine); Lee, Hae June, E-mail: haejune@pusan.ac.kr [Department of Electrical Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); Koepke, M. E. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States)

2014-07-15T23:59:59.000Z

45

Well Productivity Enhancement of High Temperature Heterogeneous Carbonate Reservoirs  

E-Print Network [OSTI]

Acidizing is one of the most popular techniques for well productivity enhancement during oil and gas production. However, the treatment method is not very effective when the wellbore penetrates through multiple layers of heterogeneous reservoirs...

Wang, Guanqun

2014-05-08T23:59:59.000Z

46

Theory of coupled whistler-electron temperature gradient mode in high beta plasma: Application to linear plasma device  

SciTech Connect (OSTI)

This paper presents a theory of coupled whistler (W) and electron temperature gradient (ETG) mode using two-fluid model in high beta plasma. Non-adiabatic ion response, parallel magnetic field perturbation ({delta}B{sub z}), perpendicular magnetic flutter ({delta}B{sub perpendicular}), and electron collisions are included in the treatment of theory. A linear dispersion relation for whistler-electron temperature gradient (W-ETG) mode is derived. The numerical results obtained from this relation are compared with the experimental results observed in large volume plasma device (LVPD) [Awasthi et al., Phys. Plasma 17, 42109 (2010)]. The theory predicts that the instability grows only where the temperature gradient is finite and the density gradient flat. For the parameters of the experiment, theoretically estimated frequency and wave number of W-ETG mode match with the values corresponding to the peak in the power spectrum observed in LVPD. By using simple mixing length argument, estimated level of fluctuations of W-ETG mode is in the range of fluctuation level observed in LVPD.

Singh, S. K.; Awasthi, L. M.; Singh, R.; Kaw, P. K.; Jha, R.; Mattoo, S. K. [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India)

2011-10-15T23:59:59.000Z

47

Excitonic enhancement of nonradiative energy transfer from a quantum well in the optical near field of energy gradient quantum dots  

E-Print Network [OSTI]

. Phys. 111, 113714 (2012) Transport of indirect excitons in a potential energy gradient Appl. Phys. Lett 30 April 2012; published online 13 June 2012) We report strong exciton migration with an efficiency (QWs) to colloidal nanocrystal quantum dots (NQDs) is criti- cal to the energy efficiency in hybrid

Demir, Hilmi Volkan

48

High-Temperature Circuit Boards for use in Geothermal Well Monitoring...  

Open Energy Info (EERE)

the very high temperatures (on the order of 350C) in EGS wells. Therefore, Composite Technology Development, Calumet, A-Power, and Sandia National Laboratory are...

49

High-Temperature Circuit Boards for Use in Geothermal Well Monitoring...  

Broader source: Energy.gov (indexed) [DOE]

Downhole Pumps Used in Geothermal Energy Production CX-001063: Categorical Exclusion Determination High Temperature, High Pressure Devices for Zonal Isolation in Geothermal Wells...

50

Temperature Prediction Model for Horizontal Well with Multiple Fractures in Shale Reservoir  

E-Print Network [OSTI]

Fracture diagnostics is a key technology for well performance prediction of a horizontal well in a shale reservoir. The combination of multiple fracture diagnostic techniques gives reliable results, and temperature data has potential to provide more...

Yoshida, Nozomu

2013-04-12T23:59:59.000Z

51

An experimental investigaion of seawater/basalt interactions: the role of water/rock ratios and temperature gradients  

E-Print Network [OSTI]

of the quench pH data as a function of temperature in temperature-gradient experiments 38 40 LIST OF PLATES Plate Page Ia Ib I la IIb IIIa IIIb IVa Ivb Va Vb VIa Large euhedral anhydrite crystals surrounded by honeycomb-shaped smectite. Run... circulation. Metabasalts ranging from zeolite to amphibolite facies, with greenstones dominating, have been dredged from the ocean floor (Aumento et al. 1971; Miyashi ro et al. 1971; Melson and van Andel, 1966; Shi do et al. , 1974; Bonatti et al. ; 1975...

Archer, Paul Lawrence

1978-01-01T23:59:59.000Z

52

Large-scale spatial variability of riverbed temperature gradients in Snake River fall Chinook salmon spawning areas  

SciTech Connect (OSTI)

In the Snake River basin of the Pacific northwestern United States, hydroelectric dam operations are often based on the predicted emergence timing of salmon fry from the riverbed. The spatial variability and complexity of surface water and riverbed temperature gradients results in emergence timing predictions that are likely to have large errors. The objectives of this study were to quantify the thermal heterogeneity between the river and riverbed in fall Chinook salmon spawning areas and to determine the effects of thermal heterogeneity on fall Chinook salmon emergence timing. This study quantified river and riverbed temperatures at 15 fall Chinook salmon spawning sites distributed in two reaches throughout 160 km of the Snake River in Hells Canyon, Idaho, USA, during three different water years. Temperatures were measured during the fall Chinook salmon incubation period with self-contained data loggers placed in the river and at three different depths below the riverbed surface. At all sites temperature increased with depth into the riverbed, including significant differences (p<0.05) in mean water temperature of up to 3.8°C between the river and the riverbed among all the sites. During each of the three water years studied, river and riverbed temperatures varied significantly among all the study sites, among the study sites within each reach, and between sites located in the two reaches. Considerable variability in riverbed temperatures among the sites resulted in fall Chinook salmon emergence timing estimates that varied by as much as 55 days, depending on the source of temperature data used for the estimate. Monitoring of riverbed temperature gradients at a range of spatial scales throughout the Snake River would provide better information for managing hydroelectric dam operations, and would aid in the design and interpretation of future empirical research into the ecological significance of physical riverine processes.

Hanrahan, Timothy P.

2007-02-01T23:59:59.000Z

53

On the nonlinear stability of a quasi-two-dimensional drift kinetic model for ion temperature gradient turbulence  

E-Print Network [OSTI]

We study a quasi-two-dimensional electrostatic drift kinetic system as a model for near-marginal ion temperature gradient (ITG) driven turbulence. A proof is given of the nonlinear stability of this system under conditions of linear stability. This proof is achieved using a transformation that diagonalizes the linear dynamics and also commutes with nonlinear $E\\times B$ advection. For the case when linear instability is present, a corollary is found that forbids nonlinear energy transfer between appropriately defined sets of stable and unstable modes. It is speculated that this may explain the preservation of linear eigenmodes in nonlinear gyrokinetic simulations. Based on this property, a dimensionally reduced ($\\infty\\times\\infty \\rightarrow 1$) system is derived that may be useful for understanding dynamics around the critical gradient of Dimits.

Plunk, G G

2015-01-01T23:59:59.000Z

54

Why molecules move along a temperature gradient Stefan Duhr, and Dieter Braun  

E-Print Network [OSTI]

and polystyrene beads, thermophoretic motion changes sign at lower temperatures. This thermophilicity toward lower

Kersting, Roland

55

Evidence of former higher temperatures from alteration minerals, Bostic 1-A well, Mountain Home, Idaho  

SciTech Connect (OSTI)

Cuttings from the silicic volcanics in the Bostic 1-A well near Mountain Home, Idaho have been examined petrographically with the assistance of x-ray diffraction and electron microprobe analyses. Results indicate that these rocks have been subjected to much higher temperatures than were observed in the well in 1974, when a static temperature log was run. It is not known to what extent the alternation may be due to greater depth of burial in the past, or whether it resulted from an early hydrothermal system of higher temperature than the one now observed.

Arney, B.

1982-01-01T23:59:59.000Z

56

Utilizing Distributed Temperature Sensors in Predicting Flow Rates in Multilateral Wells  

E-Print Network [OSTI]

and pressure data to determine the flow rate in real time out of a multilateral well. Temperature and pressure changes are harder to predict in horizontal laterals compared with vertical wells because of the lack of variation in elevation and geothermal...

Al Mulla, Jassim Mohammed A.

2012-07-16T23:59:59.000Z

57

Large-scale well aligned carbon nitride nanotube films: Low temperature growth and electron field emission  

E-Print Network [OSTI]

Large-scale well aligned carbon nitride nanotube films: Low temperature growth and electron field emission Dingyong Zhong, Shuang Liu, Guangyu Zhang, and E. G. Wanga) State Key Laboratory for Surface Received 2 January 2001; accepted for publication 13 March 2001 Large-scale well aligned carbon nitride

Zhang, Guangyu

58

Temperature-dependent quantum efficiency of Ga(N,As,P) quantum wells  

SciTech Connect (OSTI)

The photoluminescence quantum efficiencies of a series of Ga(N,As,P)/GaP multiple quantum wells are analyzed. The external quantum efficiencies are derived from the absorbed and the emitted light intensities measured using an integrating sphere mounted inside a closed-cycle helium cryostat. By taking into account the device layer sequences as well as internal reflections and reabsorption, the internal quantum efficiencies yield values above 90% for all samples at cryogenic temperatures. The temperature-dependence of the quantum efficiencies as a function of active quantum well layer design reveal the internal interfaces as remaining growth challenge in these heterostructures.

Rosemann, N. W., E-mail: Nils.Rosemann@Physik.Uni-Marburg.de; Metzger, B.; Volz, K.; Chatterjee, S. [Faculty of Physics and Material Sciences Center, Philipps-Universität Marburg, Renthof 5, D-35032 Marburg (Germany)] [Faculty of Physics and Material Sciences Center, Philipps-Universität Marburg, Renthof 5, D-35032 Marburg (Germany); Kunert, B. [NAsP III/V GmbH, Am Knechtacker 19, D-35041 Marburg (Germany)] [NAsP III/V GmbH, Am Knechtacker 19, D-35041 Marburg (Germany); Stolz, W. [Faculty of Physics and Material Sciences Center, Philipps-Universität Marburg, Renthof 5, D-35032 Marburg (Germany) [Faculty of Physics and Material Sciences Center, Philipps-Universität Marburg, Renthof 5, D-35032 Marburg (Germany); NAsP III/V GmbH, Am Knechtacker 19, D-35041 Marburg (Germany)

2013-12-16T23:59:59.000Z

59

Data acquisition for low-temperature geothermal well tests and long-term monitoring. Final report  

SciTech Connect (OSTI)

Groundwater monitoring is an essential part of the development of a low-temperature geothermal field for production and injection wells. State water resource and environmental departments are requiring both geothermal well testing and long-term monitoring as a part of the permitting process for geothermal developments. This report covers water-level measurement methods, instruments used for well testing, geochemical sampling, examples of data acquisition and regulatory mandates on groundwater monitoring.

Lienau, P.J.

1992-09-01T23:59:59.000Z

60

Data acquisition for low-temperature geothermal well tests and long-term monitoring  

SciTech Connect (OSTI)

Groundwater monitoring is an essential part of the development of a low-temperature geothermal field for production and injection wells. State water resource and environmental departments are requiring both geothermal well testing and long-term monitoring as a part of the permitting process for geothermal developments. This report covers water-level measurement methods, instruments used for well testing, geochemical sampling, examples of data acquisition and regulatory mandates on groundwater monitoring.

Lienau, P.J.

1992-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Parametric Excitation of Geodesic Acoustic Modes by Electron Drift Waves and Ion Temperature Gradient Modes in Tokamak Plasmas  

SciTech Connect (OSTI)

Geodesic Acoustic Modes (GAMs) have been predicted and subsequently observed in many toroidal plasma devices. Bicoherence studies on various devices have suggested three-wave mode coupling processes between GAMs and high frequency turbulence. Thus the parametric coupling of GAMS to drift waves and/or ion temperature gradient(ITG{r_brace} modes is a potential candidate for excitation of these modes. In this paper we discuss the resonant three-wave coupling mechanism for the excitation of GAMs by ITG and finite beta drift waves in homogeneous and inhomogeneous plasmas and compare theoretical predictions with observed characteristics of the GAMs.

Guzdar, P. N.; Kleva, R. G. [IREAP, University of Maryland, College Park, MD 20742 (United States); Chakrabarti, N. [SINP, Kolkata (India); Kaw, P. K.; Singh, R. [IPR, Gandhinagar, 308423 (India); Naulin, V.; Rasmussen, J. J. [EURATOM, Roskilde (Denmark)

2008-11-01T23:59:59.000Z

62

Determining circulating fluid temperature in drilling, workover, and well-control operations  

SciTech Connect (OSTI)

Estimation of fluid temperature in both flow conduits (drillpipe or tubing and the annulus) is required to ascertain the fluid density and viscosity and, in turn, to calculate the pressure drop or the maximum allowable pumping rate for a number of operations. These operations include drilling, workover, and well control. The fluid temperature estimation becomes critical for high-temperature or geothermal reservoirs where significant heat exchange occurs or when fluid properties are temperature sensitive, such as for a non-Newtonian fluid. In this work, the authors present an analytical model for the flowing fluid temperature in the drillpipe/tubing and in the annulus as a function of well depth and circulation time. The model is based on an energy balance between the formation and the fluid in the drillpipe.tubing and annulus. Steady-state heat transfer is assumed in the wellbore while transient heat transfer takes place in the formation. solutions are obtained for two possible scenarios: (1) the fluid flows down the annulus and up the drillpipe/tubing, and (2) the fluid flows down the tubing and up the annulus. The analytic model developed is cast in a set of simple algebraic equations for rapid implementation. The authors also show that the maximum temperature occurs not at the well bottom, but at some distance higher from the bottom for flow up the annulus.

Kabir, C.S. [Chevron Overseas Petroleum Technology Co. (Kuwait); Hasan, A.R.; Ameen, M.M. [Univ. of North Dakota, Grand Forks, ND (United States); Kouba, G.E.

1996-06-01T23:59:59.000Z

63

Coupling of ion temperature gradient and trapped electron modes in the presence of impurities in tokamak plasmas  

SciTech Connect (OSTI)

The coupling of ion temperature gradient (ITG or ?{sub i}) mode and trapped electron mode (TEM) in the presence of impurity ions is numerically investigated in toroidal collisionless plasmas, using the gyrokinetic integral eigenmode equation. A framework for excitations of the ITG modes and TEMs with respect to their driving sources is formulated first, and then the roles of impurity ions played in are analyzed comprehensively. In particular, the characteristics of the ITG and TEM instabilities in the presence of impurity ions are emphasized for both strong and weak coupling (hybrid and coexistent) cases. It is found that the impurity ions with inwardly (outwardly) peaked density profiles have stabilizing (destabilizing) effects on the hybrid (namely the TE-ITG) modes in consistence with previous works. A new finding of this work is that the impurity ions have stabilizing effects on TEMs in small ?{sub i} (?{sub i}?1) regime regardless of peaking directions of their density profiles whereas the impurity ions with density gradient L{sub ez}=L{sub ne}/L{sub nz}>1 (L{sub ez}<1) destabilize (stabilize) the TEMs in large ?{sub i} (?{sub i}?1) regime. In addition, the dependences of the growth rate, real frequency, eigenmode structure, and wave spectrum on charge concentration, charge number, and mass of impurity ions are analyzed in detail. The necessity for taking impurity ion effects on the features of turbulence into account in future transport experimental data analyses is also discussed.

Du, Huarong; Wang, Zheng-Xiong, E-mail: zxwang@dlut.edu.cn [MOE Key Laboratory of Materials Modification by Beams, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [MOE Key Laboratory of Materials Modification by Beams, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Dong, J. Q. [Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China) [Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China); Southwestern Institute of Physics, Chengdu 610041 (China); Liu, S. F. [School of Physics, Nankai University, Tianjin 300071 (China)] [School of Physics, Nankai University, Tianjin 300071 (China)

2014-05-15T23:59:59.000Z

64

Abstract : 2008 APS-DPP Temperature gradients are supported by cantori in chaotic fields  

E-Print Network [OSTI]

(s)+T(s, , ), where s is a radial coordinate. To(s) is generally a smoothed devil's staircase: flat across exceed 1010 . The temperature adapts to the fractal structure of the magnetic field. To show the connection between the fractal structure of the magnetic field and the near-fractal structure

Hudson, Stuart

65

Measuring LCSTs by Novel Temperature Gradient Methods: Evidence for Intermolecular Interactions in Mixed Polymer Solutions  

E-Print Network [OSTI]

the precipitation mechanisms are often complex, it is generally accepted that the desorption of water molecules from the temperature along the tube was a simple matter of measuring the lengthwise position. As a demonstration inverted microscope by employing dark field microscopy (Figure 2). Interestingl

66

Momentum transport in the vicinity of q{sub min} in reverse shear tokamaks due to ion temperature gradient turbulence  

SciTech Connect (OSTI)

We present an analytic study of momentum transport of tokamak plasmas in the vicinity of minimum safety factor (q) position in reversed magnetic shear configuration. Slab ion temperature gradient modes with an equilibrium flow profile are considered in this study. Quasi-linear calculations of momentum flux clearly show the novel effects of q-curvature on the generation of intrinsic rotation and mean poloidal flow without invoking reflectional symmetry breaking of parallel wavenumber (k{sub ?}). This q-curvature effect originates from the inherent asymmetry in k{sub ?} populations with respect to a rational surface due to the quadratic proportionality of k{sub ?} when q-curvature is taken into account. Discussions are made of possible implications of q-curvature induced plasma flows on internal transport barrier formation in reversed shear tokamaks.

Singh, Rameswar, E-mail: rameswar@ipr.res.in [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India) [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); Laboratoire de Physique des Plasmas, Ecole Polytechnique route de Saclay, 91128 Palaiseau Cedex (France); Singh, R [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India) [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Jhang, Hogun [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of)] [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Diamond, P. H. [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of) [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Center for Momentum Transport and Flow Organization, University of California, San Diego, California 92093 (United States); Center for Astrophysics and Space Sciences, University of California San Diego, 9500 Gilman Dr., La Jolla, California 92093-0424 (United States)

2014-01-15T23:59:59.000Z

67

A mechanistic model for computing fluid temperature profiles in gas-lift wells  

SciTech Connect (OSTI)

In a continuous-flow gas-lift operation, gas is injected down the annulus into the tubing near the top of perforations. The intrinsic idea is to aerate the liquid column, thus providing the necessary stimulus for fluid flow. Because the volumetric gas rate is dependent upon both the pressure and temperature at the depth of injection, accurate knowledge of these entities cannot be overemphasized for an efficient lift. In particular, the behavior of the nitrogen gas charged in the dome is critically dependent upon the temperature prediction for the optimal performance of the bellows-charged gas-lift valves. Current practice entails use of a linear temperature profile for the annular fluid while applying empirical correlations for the tubing fluids. Improved temperature predictions are now possible for fluids in both conduits by modeling the heat and fluid flow problem at hand from first principles. In this work, they present a mechanistic model for the flowing temperature of the annular gas and the gas/liquid two-phase mixture in the tubing as a function of both well depth and production time, regardless of the well deviation angle. The model is based on energy balance between the formation and fluids flowing through each conduit. While flowing down the annulus, the cold gas injected at the wellhead continues to gain heat. The heat-transfer rate for the annular gas depends on the relative temperatures of the formation and the tubing fluid. They assume unsteady-state heat transfer in the formation and steady-state heat transfer in the tubular for a continuous-flow gas-lift operation.

Hasan, A.R. [Univ. of North Dakota, Grand Forks, ND (United States); Kabir, C.S. [Chevron Overseas Petroleum Technology Co. (Kuwait)

1996-08-01T23:59:59.000Z

68

Outgassing, Temperature Gradients and the Radiometer Effect in LISA: A Torsion Pendulum Investigation  

E-Print Network [OSTI]

Thermal modeling of the LISA gravitational reference sensor (GRS) includes such effects as outgassing from the proof mass and its housing and the radiometer effect. Experimental data in conditions emulating the LISA GRS are required to confidently predict the GRS performance. Outgassing and the radiometer effect are similar in characteristics and are difficult to decouple experimentally. The design of our torsion balance allows us to investigate differential radiation pressure, the radiometer effect, and outgassing on closely separated conducting surfaces with high sensitivity. A thermally controlled split copper plate is brought near a freely hanging plate-torsion pendulum.We have varied the temperature on each half of the copper plate and have measured the resulting forces on the pendulum. We have determined that to first order the current GRS model for the radiometer effect, outgassing, and radiation pressure are mostly consistent with our torsion balance measurements and therefore these thermal effects do not appear to be a large hindrance to the LISA noise budget. However, there remain discrepancies between the predicted dependence of these effects on the temperature of our apparatus.

Scott E Pollack; Stephan Schlamminger; Jens H Gundlach

2007-02-08T23:59:59.000Z

69

Low temperature carrier redistribution dynamics in InGaN/GaN quantum wells  

SciTech Connect (OSTI)

We have studied the carrier recombination dynamics in an InGaN/GaN multiple quantum well structure as a function of emission energy and excitation density between temperatures of 10?K and 100?K. Under relatively low levels of excitation, the photoluminescence (PL) intensity and decay time of emission on the high energy side of the luminescence spectrum decrease strongly between 10?K and 50?K. In contrast, for emission detected on the low energy side of the spectrum, the PL intensity and decay time increase over the same temperature range. These results are consistent with a thermally activated carrier redistribution process in which the (temperature dependent) average timescale for carrier transfer into or out of a localised state depends on the energy of the given state. Thus, the transfer time out of shallow, weakly localised states is considerably shorter than the arrival time into more deeply localised states. This picture is consistent with carriers hopping between localisation sites in an uncorrelated disorder potential where the density of localised states decreases with increasing localisation depth, e.g., a exponential or Gaussian distribution resulting from random alloy disorder. Under significantly higher levels of excitation, the increased occupation fraction of the localised states results in a greater average separation distance between unoccupied localised states, causing a suppression of the spectral and dynamic signatures of the hopping transfer of carriers.

Badcock, T. J., E-mail: Thomas.badcock@crl.toshiba.co.uk; Dawson, P.; Davies, M. J. [School of Physics and Astronomy, Photon Science Institute, Alan Turing Building, University of Manchester, Manchester M13 9PL (United Kingdom); Kappers, M. J.; Massabuau, F. C.-P.; Oehler, F.; Oliver, R. A.; Humphreys, C. J. [Department of Materials Science and Metallurgy, 27 Charles Babbage Road, University of Cambridge, Cambridge CB3 0FS (United Kingdom)

2014-03-21T23:59:59.000Z

70

Statistical mechanical theory for the structure of steady state systems: Application to a Lennard-Jones fluid with applied temperature gradient  

E-Print Network [OSTI]

Statistical mechanical theory for the structure of steady state systems: Application to a Lennard-Jones fluid with applied temperature gradient Phil Attard School of Chemistry F11, University of Sydney, New statistical mechanics for inhomogeneous systems may now be applied to determining the structure

Attard, Phil

71

A circular equilibrium model for local gyrokinetic simulations of ion temperature gradient fluctuations in reversed field pinches  

SciTech Connect (OSTI)

A simple large-aspect-ratio (R{sub 0}/r) circular equilibrium model is developed for low-beta reversed field pinch (RFP) geometry. The model is suitable for treating small scale instability and turbulent transport driven by ion temperature gradient (ITG) and related electron drift modes in gyrokinetic simulations. The equilibrium model is an RFP generalization of the common tokamak s-{alpha} model to small safety factor (q), where the poloidal field dominates the toroidal field. The model accommodates the RFP toroidal field reversal (where q vanishes) by generalizing the cylindrical force-free Bessel function model (BFM) [J. B. Taylor, Phys. Rev. Lett. 33, 1139 (1974)] to toroidal geometry. The global equilibrium can be described in terms of the RFP field reversal and pinch parameters [F,{Theta}]. This new toroidal Bessel function model (TBFM) has been incorporated into the gyrokinetic code GYRO [J. Candy and R. E. Waltz, J.Comput. Phys. 186, 545 (2003)] and used here to explore local electrostatic ITG adiabatic electron instability rates for typical low-q RFP parameters.

Tangri, Varun; Terry, P. W. [Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, Wisconsin 53706R (United States); Waltz, R. E. [General Atomics, San Diego, California 92186 (United States)

2011-05-15T23:59:59.000Z

72

Geothermal: Sponsored by OSTI -- Temperatures and intervalgeothermal...  

Office of Scientific and Technical Information (OSTI)

Temperatures and interval geothermal-gradient determinations from wells in National Petroleum Reserve in Alaska Geothermal Technologies Legacy Collection HelpFAQ | Site Map |...

73

Design, prototyping, and testing of an apparatus for establishing a linear temperature gradient in experimental fish tanks  

E-Print Network [OSTI]

Immunology researchers require a new type of fish tank that provides a linear thermal gradient for experimental zebrafish in order to improve the accuracy and validity of their research. Zebrafish require the ability to ...

Kadri, Romi Sinclair

2014-01-01T23:59:59.000Z

74

High Temperature, High Pressure Devices for Zonal Isolation in Geothermal Wells  

Broader source: Energy.gov [DOE]

DOE Geothermal Peer Review 2010 - Presentation. Project objectives: Design, demonstrate, and qualify high-temperature high pressure zonal isolation devices compatible with the high temperature downhole Enhanced Geothermal Systems (EGS) environment.

75

High-Temperature Circuit Boards for Use in Geothermal Well Monitoring Applications  

Broader source: Energy.gov [DOE]

Project objective: Develop and demonstrate high-temperature; multilayer electronic circuits capable of sustained operation at 300? C.

76

High-Temperature Circuit Boards for Use in Geothermal Well Monitoring...  

Broader source: Energy.gov (indexed) [DOE]

Composite Technology Development, Inc. High-Temperature Tools and Sensors, Downhole Pumps and Drilling May 19, 2010 This presentation does not contain any proprietary...

77

Detecting and modeling cement failure in high pressure/ high temperature wells using finite-element method  

E-Print Network [OSTI]

conditions and are investigated simultaneously to more accurately predict cement failure. The results of this study show the relevant dependency of stress principles with temperature and pressure. These results clarify the deformation caused by any...

Shahri, Mehdi Abbaszadeh

2006-04-12T23:59:59.000Z

78

A robust and well shielded thermal conductivity device for low temperature measurements  

SciTech Connect (OSTI)

We present a compact mechanically robust thermal conductivity measurement apparatus for measurements at low temperatures (<1 K) and high magnetic fields on small high-purity single crystal samples. A high-conductivity copper box is used to enclose the sample and all the components. The box provides protection for the thermometers, heater, and most importantly the sample increasing the portability of the mount. In addition to physical protection, the copper box is also effective at shielding radio frequency electromagnetic interference and thermal radiation, which is essential for low temperature measurements. A printed circuit board in conjunction with a braided ribbon cable is used to organize the delicate wiring and provide mechanical robustness.

Toews, W. H.; Hill, R. W. [GWPI and Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)] [GWPI and Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)

2014-04-15T23:59:59.000Z

79

Low temperature barriers with heat interceptor wells for in situ processes  

DOE Patents [OSTI]

A system for reducing heat load applied to a frozen barrier by a heated formation is described. The system includes heat interceptor wells positioned between the heated formation and the frozen barrier. Fluid is positioned in the heat interceptor wells. Heat transfers from the formation to the fluid to reduce the heat load applied to the frozen barrier.

McKinzie, II, Billy John (Houston, TX)

2008-10-14T23:59:59.000Z

80

High-Temperature Circuit Boards for use in Geothermal Well Monitoring  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy Resources Jump to: navigation,Ohio:GreerHi Gtel Jump to: navigation,Solar Power PlantWellsNational Park

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Low-temperature geothermal water in Utah: A compilation of data for thermal wells and springs through 1993  

SciTech Connect (OSTI)

The Geothermal Division of DOE initiated the Low-Temperature Geothermal Resources and Technology Transfer Program, following a special appropriation by Congress in 1991, to encourage wider use of lower-temperature geothermal resources through direct-use, geothermal heat-pump, and binary-cycle power conversion technologies. The Oregon Institute of Technology (OIT), the University of Utah Research Institute (UURI), and the Idaho Water Resources Research Institute organized the federally-funded program and enlisted the help of ten western states to carry out phase one. This first phase involves updating the inventory of thermal wells and springs with the help of the participating state agencies. The state resource teams inventory thermal wells and springs, and compile relevant information on each sources. OIT and UURI cooperatively administer the program. OIT provides overall contract management while UURI provides technical direction to the state teams. Phase one of the program focuses on replacing part of GEOTHERM by building a new database of low- and moderate-temperature geothermal systems for use on personal computers. For Utah, this involved (1) identifying sources of geothermal date, (2) designing a database structure, (3) entering the new date; (4) checking for errors, inconsistencies, and duplicate records; (5) organizing the data into reporting formats; and (6) generating a map (1:750,000 scale) of Utah showing the locations and record identification numbers of thermal wells and springs.

Blackett, R.E.

1994-07-01T23:59:59.000Z

82

Room temperature continuous wave InGaAsN quantum well vertical cavity lasers emitting at 1.3 um  

SciTech Connect (OSTI)

Selectively oxidized vertical cavity lasers emitting at 1294 nm using InGaAsN quantum wells are reported for the first time which operate continuous wave at and above room temperature. The lasers employ two n-type Al{sub 0.94}Ga{sub 0.06}As/GaAs distributed Bragg reflectors each with a selectively oxidized current aperture adjacent to the optical cavity, and the top output mirror contains a tunnel junction to inject holes into the active region. Continuous wave single mode lasing is observed up to 55 C. These lasers exhibit the longest wavelength reported to date for vertical cavity surface emitting lasers grown on GaAs substrates.

CHOQUETTE,KENT D.; KLEM,JOHN F.; FISCHER,ARTHUR J.; SPAHN,OLGA B.; ALLERMAN,ANDREW A.; FRITZ,IAN J.; KURTZ,STEVEN R.; BREILAND,WILLIAM G.; SIEG,ROBERT M.; GEIB,KENT M.; SCOTT,J.W.; NAONE,R.L.

2000-06-05T23:59:59.000Z

83

Hypoxia is well known to reduce metabolism and body temperature in many vertebrates (Wood and Gonzales, 1996),  

E-Print Network [OSTI]

using infrared thermography to measure the surface temperatures of the golden-mantled ground squirrel

Tattersall, Glenn

84

Core-shell multi-quantum wells in ZnO / ZnMgO nanowires with high optical efficiency at room temperature  

E-Print Network [OSTI]

Nanowire-based light-emitting devices require multi-quantum well heterostructures with high room temperature optical efficiencies. We demonstrate that such efficiencies can be attained through the use of ZnO/Zn(1-x)MgxO core shell quantum well heterostructures grown by metal organic vapour phase epitaxy. Varying the barrier Mg concentration from x=0.15 to x=0.3 leads to the formation of misfit induced dislocations in the multi quantum wells. Correlatively, temperature dependant photoluminescence reveals that the radial well luminescence intensity decreases much less rapidly with increasing temperature for the lower Mg concentration. Indeed, about 54% of the 10K intensity is retained at room temperature with x=0.15, against 2% with x=0.30. Those results open the way to the realization of high optical efficiency nanowire-based light emitting diodes.

Thierry, Robin; Jouneau, Pierre-Henri; Ferret, Pierre; Feuillet, Guy; 10.1088/0957-4484/23/8/085705

2013-01-01T23:59:59.000Z

85

Effects of bias and temperature on the intersubband absorption in very long wavelength GaAs/AlGaAs quantum well infrared photodetectors  

SciTech Connect (OSTI)

The temperature- and bias-dependent photocurrent spectra of very long wavelength GaAs/AlGaAs quantum well infrared photodetectors (QWIPs) are studied using spectroscopic measurements and corresponding theoretical calculations. It is found that the peak response wavelength will shift as the bias and temperature change. Aided by band structure calculations, we propose a model of the double excited states and explain the experimental observations very well. In addition, the working mechanisms of the quasi-bound state confined in the quantum well, including the processes of tunneling and thermionic emission, are also investigated in detail. We confirm that the first excited state, which belongs to the quasi-bound state, can be converted into a quasi-continuum state induced by bias and temperature. These obtained results provide a full understanding of the bound-to-quasi-bound state and the bound-to-quasi-continuum state transition, and thus allow for a better optimization of QWIPs performance.

Liu, X. H.; Zhou, X. H., E-mail: xhzhou@mail.sitp.ac.cn; Li, N.; Liao, K. S.; Huang, L.; Li, Q.; Li, Z. F.; Chen, P. P.; Lu, W. [National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-Tian Road, Shanghai 200083 (China); Wang, L.; Sun, Q. L. [Institute of Physics, Chinese Academy of Sciences, Beijing 100080 (China)

2014-03-28T23:59:59.000Z

86

Gradient elution in capillary electrochromatography  

SciTech Connect (OSTI)

In analogy to pressure-driven gradient techniques in high-performance liquid chromatography, a system has been developed for delivering electroosmotically-driven solvent gradients for capillary electrochromatography (CEC). Dynamic gradients with sub-mL/min flow rates are generated by merging two electroosmotic flows that are regulated by computer-controlled voltages. These flows are delivered by two fused-silica capillary arms attached to a T-connector, where they mix and then flow into a capillary column that has been electrokinetically packed with 3-mm reversed-phase particles. The inlet of one capillary arm is placed in a solution reservoir containing one mobile phase and the inlet of the other is placed in a second reservoir containing a second mobile phase. Two independent computer-controlled programmable high-voltage power supplies (0-50 kV)--one providing an increasing ramp and the other providing a decreasing ramp--are used to apply variable high-voltage potentials to the mobile phase reservoirs to regulate the electroosmotic flow in each arm. The ratio of the electroosmotic flow rates between the two arms is changed with time according to the computer-controlled voltages to deliver the required gradient profile to the separation column. Experiments were performed to confirm the composition of the mobile phase during a gradient run and to determine the change of the composition in response to the programmed voltage profile. To demonstrate the performance of electroosmotically-driven gradient elution in CEC, a mixture of 16 polycyclic aromatic hydrocarbons (PAHs) was separated in less than 90 minutes. This gradient technique is expected to be well-suited for generating not only solvent gradients in CEC, but also other types of gradients such as pH- and ionic-strength gradients in capillary electrokinetic separations and analyses.

Anex, D.; Rakestraw, D.J. [Sandia National Labs., Livermore, CA (United States); Yan, Chao; Dadoo, R.; Zare, R.N. [Stanford Univ., CA (United States). Dept. of Chemistry

1997-08-01T23:59:59.000Z

87

Introduction Conjugate Gradient Method  

E-Print Network [OSTI]

Introduction Conjugate Gradient Method Deflation Domain Decomposition Research Master Thesis Presentation #12;Introduction Conjugate Gradient Method Deflation Domain Decomposition Research Plaxis Finite Kaliszka Master Thesis Literature Study Presentation #12;Introduction Conjugate Gradient Method Deflation

Vuik, Kees

88

Room-temperature mid-infrared “M”-type GaAsSb/InGaAs quantum well lasers on InP substrate  

SciTech Connect (OSTI)

We have demonstrated experimentally the InP-based “M”-type GaAsSb/InGaAs quantum-well (QW) laser lasing at 2.41??m at room temperature by optical pumping. The threshold power density per QW and extracted internal loss were about 234?W/cm{sup 2} and 20.5?cm{sup ?1}, respectively. The temperature-dependent photoluminescence (PL) and lasing spectra revealed interesting characteristics for this type of lasers. Two distinct regions in the temperature dependent threshold behavior were observed and the transition temperature was found to coincide with the cross over point of the PL and lasing emission peaks. The current-voltage characteristic of “M”-type QW laser was superior to the inverse “W”-type one due to its thinner barrier for holes. Further improvement of the “M”-type QW structure could lead to a cost-effective mid-infrared light source.

Chang, Chia-Hao; Li, Zong-Lin; Pan, Chien-Hung; Lu, Hong-Ting; Lee, Chien-Ping; Lin, Sheng-Di, E-mail: sdlin@mail.nctu.edu.tw [Department of Electronics Engineering, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan (China)

2014-02-14T23:59:59.000Z

89

Geosynthetics in a salinity-gradient solar pond environment  

SciTech Connect (OSTI)

This paper describes the latest in salinity-gradient solar pond lining systems. The high-temperature, high-salinity environment unique to a salinity-gradient solar pond resulted in failure of the geomembrane liner at the El Paso Solar Pond Test Facility after only eight years of operation. Research involved in pond reconstruction led to the selection of a lining system consisting of a flexible polypropylene (PP) geomembrane for the sidewalls and a specially formulated geosynthetic clay liner (GCL) on the bottom of the pond. The two liners have been installed and a comprehensive test program is being conducted to measure their performance. The environment encountered in a salinity-gradient solar pond will be discussed as well as material selection criteria and the design of the two liners. Preliminary results of the GCL performance monitoring will also be presented.

Lichwardt, M.A.; Comer, A.I.

1997-11-01T23:59:59.000Z

90

Evidence Estimation for Bayesian Partially Observed MRFs Yutian Chen Max Welling  

E-Print Network [OSTI]

(2006) use Langevin dynamics with approximate gradients, Welling and Parise (2006); Parise and Welling

Welling, Max

91

Geothermal gradient map of the conterminous United States. Second edition  

SciTech Connect (OSTI)

The second edition of the Geothermal Gradient Map of the Conterminous United States (Kron and Stix 1982) is described and the changes made since the first edition (Kron and Heiken 1980) are compared. The second edition of the map presents a compilation of over 1700 wells that have been measured for temperature belwo 50 m and whose temperature/depth profiles are linear, or composed of linear segments which reflect changes in the thermal conductivity of the rocks rather than hydrology. The data are displayed at an enlarged scale of 1:2,500,000 and in a new format which shows the location, depth, and gradient of each well in a single color-coded symbol. This edition contains over two times the amount of data shown on the first map and is accompained by a table, listing for each well its location, depth, gradient, heat flow (where available), thermal conductivity (where available), and a reference. Over 200 references have been consulted and are presented with the data.

Kron, A.; Stix, J.

1982-01-01T23:59:59.000Z

92

On the connection between the conjugate gradient method and ...  

E-Print Network [OSTI]

Feb 9, 2013 ... Abstract: It is well known that the conjugate gradient method and a quasi-Newton method, using any well-defined update matrix from the ...

Anders Forsgren

2013-02-09T23:59:59.000Z

93

Study of thermal-gradient-induced migration of brine inclusions in salt. Final report  

SciTech Connect (OSTI)

Natural salt deposits, which are being considered for high-level waste disposal, contain a small volume fraction of water in the form of brine inclusions distributed throughout the salt. Radioactive decay heating of the nuclear wastes will impose a temperature gradient on the surrounding salt which mobilizes the brine inclusions. Inclusions filled completely with brine (the all-liquid inclusions) migrate up the temperature gradient and eventually accumulate brine near the buried waste forms. The brine may slowly corrode or degrade the waste forms, which is undesirable. Therefore it is important to consider the migration of brine inclusions in salt under imposed temperature gradients to properly evaluate the performance of a future salt repository for nuclear wastes. The migration velocities of the inclusions were found to be dependent on temperature, temperature gradient, and inclusion shape and size. The velocities were also dictated by the interfacial mass transfer resistance at brine/solid interface. This interfacial resistance depends on the dislocation density in the crystal, which in turn, depends on the axial compressive loading of the crystal. At low axial loads, the dependence between the velocity and temperature gradient is nonlinear. At high axial loads, the interfacial resistance is reduced and the migration velocity depends linearly on the temperature gradient. All-liquid inclusions filled with mixed brines were also studied. For gas-liquid inclusions, helium, air and argon were compared. Migration studies were also conducted on single crystallites of natural salt as well as in polycrystalline natural salt samples. The behavior of the inclusions at large-ange grain boundaries was observed.

Olander, D.R.

1984-08-01T23:59:59.000Z

94

Magnetic and dielectric behavior of the spin-chain compound Er{sub 2}BaNiO{sub 5} well below its Néel temperature  

SciTech Connect (OSTI)

We have recently reported that the Haldane spin-chain system, Er{sub 2}BaNiO{sub 5}, undergoing antiferromagnetic order below (T{sub N}=) 32?K, is characterized by the onset of ferroelectricity near 60?K due to magnetoelectric coupling induced by short-range magnetic-order within spin-chains. We have carried out additional magnetic and dielectric studies to understand the properties well below T{sub N}. We emphasize here on the following: (i) A strong frequency dependent behaviors of ac magnetic susceptibility and complex dielectric properties have been observed at much lower temperatures (<8?K), that is, “reentrant multiglass-like” phenomenon, naturally suggesting the existence of an additional transition well below T{sub N}. (ii) “Magnetoelectric phase coexistence” is observed at very low temperature (e.g., T?=?2?K), where the high-field magnetoelectric phase is partially arrested on returning to zero magnetic field after a cycling through metamagnetic transition.

Basu, Tathamay; Singh, Kiran; Sampathkumaran, E. V. [Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005 (India); Mohapatra, N. [School of Basic Sciences, Indian Institute of Technology Bhubaneshwar, Bhubaneshwar 751013 (India)

2014-09-21T23:59:59.000Z

95

Simplified modeling of liquid sodium medium with temperature and velocity gradient using real thermal-hydraulic data. Application to ultrasonic thermometry in sodium fast reactor  

SciTech Connect (OSTI)

In the framework of the French R and D program for the Generation IV reactors and specifically for the sodium cooled fast reactors (SFR), studies are carried out on innovative instrumentation methods in order to improve safety and to simplify the monitoring of fundamental physical parameters during reactor operation. The aim of the present work is to develop an acoustic thermometry method to follow up the sodium temperature at the outlet of subassemblies. The medium is a turbulent flow of liquid sodium at 550 Degree-Sign C with temperature inhomogeneities. To understand the effect of disturbance created by this medium, numerical simulations are proposed. A ray tracing code has been developed with Matlab Copyright-Sign in order to predict acoustic paths in this medium. This complex medium is accurately described by thermal-hydraulic data which are issued from a simulation of a real experiment in Japan. The analysis of these results allows understanding the effects of medium inhomogeneities on the further thermometric acoustic measurement.

Massacret, N.; Jeannot, J. P. [DEN/DTN/STPA/LIET, CEA Cadarache, Saint Paul Lez Durance (France); Moysan, J.; Ploix, M. A.; Corneloup, G. [Aix-Marseille Univ, LMA UPR 7051 CNRS, site LCND, 13625 Aix-en-Provence (France)

2013-01-25T23:59:59.000Z

96

Observation of room temperature optical absorption in InP/GaAs type-II ultrathin quantum wells and quantum dots  

SciTech Connect (OSTI)

Room temperature optical absorption process is observed in ultrathin quantum wells (QWs) and quantum dots (QDs) of InP/GaAs type-II band alignment system using surface photovoltage spectroscopy technique, where no measurable photoluminescence signal is available. Clear signature of absorption edge in the sub band gap region of GaAs barrier layer is observed for the ultrathin QWs and QDs, which red shifts with the amount of deposited InP material. Movement of photogenerated holes towards the sample surface is proposed to be the main mechanism for the generation of surface photovoltage in type-II ultrathin QWs and QDs. QDs of smaller size are found to be free from the dislocations as confirmed by the high resolution transmission electron microscopy images.

Singh, S. D., E-mail: devsh@rrcat.gov.in; Porwal, S.; Mondal, Puspen; Srivastava, A. K.; Mukherjee, C.; Dixit, V. K.; Sharma, T. K.; Oak, S. M. [Raja Ramanna Centre for Advanced Technology, Indore-452013, Madhya Pradesh (India)

2014-06-14T23:59:59.000Z

97

The ISO Galactic Metallicity Gradient Revisited  

E-Print Network [OSTI]

Two independent groups (Giveon et al. 2002; Martin-Hernandez et al. 2002) have recently investigated the Galactic metallicity gradient as probed by ISO observations of mid-infrared emission lines from HII regions. We show that the different gradients inferred by the two groups are due to differing source selection and differing extinction corrections. We show that both data sets in fact provide consistent results if identical assumptions are made in the analysis. We present a consistent set of gradients in which we account for extinction and variation in electron temperature across the disk.

Uriel Giveon; Christophe Morisset; Amiel Sternberg

2002-07-22T23:59:59.000Z

98

ON THE CONNECTION BETWEEN THE CONJUGATE GRADIENT METHOD AND  

E-Print Network [OSTI]

ON THE CONNECTION BETWEEN THE CONJUGATE GRADIENT METHOD AND QUASI-NEWTON METHODS ON QUADRATIC Royal Institute of Technology February 2013 Abstract It is well known that the conjugate gradient method gradient method. In the framework based on a sufficient condition to obtain mutually conjugate search

Forsgren, Anders

99

APPROXIMATE INVERSE PRECONDITIONING FOR THE CONJUGATE GRADIENT METHOD  

E-Print Network [OSTI]

APPROXIMATE INVERSE PRECONDITIONING FOR THE CONJUGATE GRADIENT METHOD ON A VECTOR COMPUTER Michele definite matrix, by the preconditioned conjugate gradient method (PCG) (see, e.g., [4]). It is well of the conjugate gradient method reduces to computing a matrix­ vector product with G, an operation which offers

Tùma, Miroslav

100

Variable metric conjugate gradient methods  

SciTech Connect (OSTI)

1.1 Motivation. In this paper we present a framework that includes many well known iterative methods for the solution of nonsymmetric linear systems of equations, Ax = b. Section 2 begins with a brief review of the conjugate gradient method. Next, we describe a broader class of methods, known as projection methods, to which the conjugate gradient (CG) method and most conjugate gradient-like methods belong. The concept of a method having either a fixed or a variable metric is introduced. Methods that have a metric are referred to as either fixed or variable metric methods. Some relationships between projection methods and fixed (variable) metric methods are discussed. The main emphasis of the remainder of this paper is on variable metric methods. In Section 3 we show how the biconjugate gradient (BCG), and the quasi-minimal residual (QMR) methods fit into this framework as variable metric methods. By modifying the underlying Lanczos biorthogonalization process used in the implementation of BCG and QMR, we obtain other variable metric methods. These, we refer to as generalizations of BCG and QMR.

Barth, T.; Manteuffel, T.

1994-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Converting Level Set Gradients to Shape Gradients  

E-Print Network [OSTI]

distance function (SDF) associated with a shape, and differentiate these energies with respect to the SDF to the SDF. We discuss some problematic gradients from the literature, show how they can easily be fixed function (SDF) of , i.e. the function that associates any point x with the signed distance (x) = ±d

Radke, Rich

102

Photo of the Week: The Alternating Gradient Synchrotron | Department...  

Broader source: Energy.gov (indexed) [DOE]

Gradient Synchrotron (AGS) has been one of the world's premiere particle accelerators, well known for the

103

Thermal Gradient Holes At North Brawley Geothermal Area (Edmunds...  

Open Energy Info (EERE)

of the North Brawley, Heber, East Mesa, and Salton Sea Geothermal Areas. Notes Well logs, thermal gradient data, and magnetic data were correlated to form a better geologic...

104

Fast Self-Healing Gradients  

E-Print Network [OSTI]

We present CRF-Gradient, a self-healing gradient algorithm that provably reconfigures in O(diameter) time. Self-healing gradients are a frequently used building block for distributed self-healing systems, but previous ...

Beal, Jacob

105

Inverse estimation of surface heating condition in a three-dimensional object using conjugate gradient method  

E-Print Network [OSTI]

heat conduction Laser Gaussian profile Conjugate gradient method a b s t r a c t Temperature and heat gradient method Jianhua Zhou, Yuwen Zhang *, J.K. Chen, Z.C. Feng Department of Mechanical and Aerospace gradient method (CGM) with temperature and heat flux measured on back surface (opposite to the heated

Zhang, Yuwen

106

Multi-gradient drilling method and system  

DOE Patents [OSTI]

A multi-gradient system for drilling a well bore from a surface location into a seabed includes an injector for injecting buoyant substantially incompressible articles into a column of drilling fluid associated with the well bore. Preferably, the substantially incompressible articles comprises hollow substantially spherical bodies.

Maurer, William C. (Houston, TX); Medley, Jr., George H. (Spring, TX); McDonald, William J. (Houston, TX)

2003-01-01T23:59:59.000Z

107

Elevated temperature crack propagation  

SciTech Connect (OSTI)

This paper is a summary of two NASA contracts on high temperature fatigue crack propagation in metals. The first evaluated the ability of fairly simple nonlinear fracture parameters to correlate crack propagation. Hastelloy-X specimens were tested under isothermal and thermomechanical cycling at temperatures up to 980 degrees C (1800 degrees F). The most successful correlating parameter was the crack tip opening displacement derived from the J-integral. The second evaluated the ability of several path-independent integrals to correlate crack propagation behavior. Inconel 718 specimens were tested under isothermal, thermomechanical, temperature gradient, and creep conditions at temperatures up to 650 degrees C (1200 degrees F). The integrals formulated by Blackburn and by Kishimoto correlated the data reasonably well under all test conditions.

Orange, T.W.

1994-02-01T23:59:59.000Z

108

Pumpernickel Valley Geothermal Project Thermal Gradient Wells | Open Energy  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: EnergyPotentialUrbanUtilityScalePVCapacityPulaski County, Kentucky: Energy Resources Jump to:Pulte

109

Conjugate Gradient Method Numerisches Rechnen  

E-Print Network [OSTI]

Conjugate Gradient Method Numerisches Rechnen (für Informatiker) M. Grepl J. Berger & J.T. Frings Numerisches Rechnen #12;Conjugate Gradient Method The Quadratic Form Steepest Descent Conjugate Directions/Gradients IGPM, RWTH Aachen Numerisches Rechnen #12;Conjugate Gradient Method The Quadratic Form Steepest Descent

110

Field application of an interpretation method of downhole temperature and pressure data for detecting water entry in horizontal/highly inclined gas wells  

E-Print Network [OSTI]

condition change, wellbore structure change, geothermal environment change, or simple just noise of measurement. To separate flow condition change from the other causes of temperature change, we require a comprehensive understanding of flow dynamics. 5.... The interpretation model for downhole temperature and pressure data is a coupled thermal wellbore/reservoir flow model. The model is built on fundamental flow and energy conservation equations for both the reservoir and wellbore. These equations are: Mass balance...

Achinivu, Ochi I.

2009-05-15T23:59:59.000Z

111

on the connection between the conjugate gradient method and ...  

E-Print Network [OSTI]

It is well known that the conjugate gradient method and a quasi-Newton method, using any well-defined update matrix from the one-parameter Broy- den family ...

2013-02-07T23:59:59.000Z

112

Hanford wells  

SciTech Connect (OSTI)

Records describing wells located on or near the Hanford Site have been maintained by Pacific Northwest Laboratory and the operating contractor, Westinghouse Hanford Company. In support of the Ground-Water Surveillance Project, portions of the data contained in these records have been compiled into the following report, which is intended to be used by those needing a condensed, tabular summary of well location and basic construction information. The wells listed in this report were constructed over a period of time spanning almost 70 years. Data included in this report were retrieved from the Hanford Envirorunental Information System (HEIS) database and supplemented with information not yet entered into HEIS. While considerable effort has been made to obtain the most accurate and complete tabulations possible of the Hanford Site wells, omissions and errors may exist. This document does not include data on lithologic logs, ground-water analyses, or specific well completion details.

Chamness, M.A.; Merz, J.K.

1993-08-01T23:59:59.000Z

113

Polyelectrolyte Complex Nanoparticles for Protection and Delayed Release of Enzymes in Alkaline pH and at Elevated Temperature during Hydraulic Fracturing of Oil Wells  

E-Print Network [OSTI]

Polyethylenimine-dextran sulfate polyelectrolyte complexes (PEC) were used to entrap two enzymes used to degrade polymer gels following hydraulic fracturing of oil wells in order to obtain delayed release and to protect ...

Barati Ghahfarokhi, Reza; Johnson, Stephen J.; McCool, Stan; Green, Don W.; Willhite, G. Paul; Liang, Jenn-Tai

2012-01-01T23:59:59.000Z

114

Temperature, heat flow maps and temperature gradient holes | Open Energy  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revisionEnvReviewNonInvasiveExplorationUT-gTaguspark Jump to: navigation,Telluric Survey Details

115

Dimensions of Wellness Staying Well  

E-Print Network [OSTI]

to protect your physical health by eating a well-balanced diet, getting plenty of physical activity-evaluation and self-assessment. Wellness involves continually learning and making changes to enhance your state) A state in which your mind is engaged in lively interaction with the world around you. Intellectual

Fernandez, Eduardo

116

Growths of staggered InGaN quantum wells light-emitting diodes emitting at 520525 nm employing graded growth-temperature profile  

E-Print Network [OSTI]

Growths of staggered InGaN quantum wells light-emitting diodes emitting at 520­525 nm employing current spreading and light extraction in GaN-based light emitting diodes Appl. Phys. Lett. 100, 061107 (2012) Electrically driven nanopyramid green light emitting diode Appl. Phys. Lett. 100, 061106 (2012

Gilchrist, James F.

117

Monitoring well  

DOE Patents [OSTI]

A monitoring well including a conduit defining a passageway, the conduit having a proximal and opposite, distal end; a coupler connected in fluid flowing relationship with the passageway; and a porous housing borne by the coupler and connected in fluid flowing relation thereto.

Hubbell, Joel M. (Idaho Falls, ID); Sisson, James B. (Idaho Falls, ID)

1999-01-01T23:59:59.000Z

118

Monitoring well  

DOE Patents [OSTI]

A monitoring well is described which includes: a conduit defining a passageway, the conduit having a proximal and opposite, distal end; a coupler connected in fluid flowing relationship with the passageway; and a porous housing borne by the coupler and connected in fluid flowing relation thereto. 8 figs.

Hubbell, J.M.; Sisson, J.B.

1999-06-29T23:59:59.000Z

119

Geothermal well stimulation  

SciTech Connect (OSTI)

All available data on proppants and fluids were examined to determine areas in technology that need development for 300 to 500/sup 0/F (150/sup 0/ to 265/sup 0/C) hydrothermal wells. While fluid properties have been examined well into the 450/sup 0/F range, proppants have not been previously tested at elevated temperatures except in a few instances. The latest test data at geothermal temperatures is presented and some possible proppants and fluid systems that can be used are shown. Also discussed are alternative stimulation techniques for geothermal wells.

Sinclair, A.R.; Pittard, F.J.; Hanold, R.J.

1980-01-01T23:59:59.000Z

120

Monitoring well  

DOE Patents [OSTI]

The present invention relates to a monitoring well which includes an enclosure defining a cavity and a water reservoir enclosed within the cavity and wherein the reservoir has an inlet and an outlet. The monitoring well further includes a porous housing borne by the enclosure and which defines a fluid chamber which is oriented in fluid communication with the outlet of the reservoir, and wherein the porous housing is positioned in an earthen soil location below-grade. A geophysical monitoring device is provided and mounted in sensing relation relative to the fluid chamber of the porous housing; and a coupler is selectively moveable relative to the outlet of reservoir to couple the porous housing and water reservoir in fluid communication. An actuator is coupled in force transmitting relation relative to the coupler to selectively position the coupler in a location to allow fluid communication between the reservoir and the fluid chamber defined by the porous housing.

Hubbell, Joel M. (Idaho Falls, ID); Sisson, James B. (Idaho Falls, ID)

2002-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Isobaric groundwater well  

DOE Patents [OSTI]

A method of measuring a parameter in a well, under isobaric conditions, including such parameters as hydraulic gradient, pressure, water level, soil moisture content and/or aquifer properties the method as presented comprising providing a casing having first and second opposite ends, and a length between the ends, the casing supporting a transducer having a reference port; placing the casing lengthwise into the well, second end first, with the reference port vented above the water table in the well; and sealing the first end. A system is presented for measuring a parameter in a well, the system comprising a casing having first and second opposite ends, and a length between the ends and being configured to be placed lengthwise into a well second end first; a transducer, the transducer having a reference port, the reference port being vented in the well above the water table, the casing being screened across and above the water table; and a sealing member sealing the first end. In one embodiment, the transducer is a tensiometer transducer and in other described embodiments, another type transducer is used in addition to a tensiometer.

Hubbell, Joel M. (Idaho Falls, ID); Sisson, James B. (Idaho Falls, ID)

1999-01-01T23:59:59.000Z

122

Conjugate Gradient Methods in Confirmatory Factor Analysis  

E-Print Network [OSTI]

R. I. (1988), "Conjugate Gradient Methods in Confirmatoryapply generalized conjugate gradient methods in an attemptby used. The conjugate gradient method, which is simple and

Jamshardian, Mortaza; Jennrich, Robert

1993-01-01T23:59:59.000Z

123

Conjugate Gradient Acceleration of the EM Algorithm  

E-Print Network [OSTI]

R. I. (1988), "Conjugate Gradient Methods in Confirmatoryapply generalized conjugate gradient methods in an attemptby used. The conjugate gradient method, which is simple and

Mortaza Jamshidian; Robert Jennrich

2011-01-01T23:59:59.000Z

124

Energy in density gradient  

E-Print Network [OSTI]

Inhomogeneous plasmas and fluids contain energy stored in inhomogeneity and they naturally tend to relax into lower energy states by developing instabilities or by diffusion. But the actual amount of energy in such inhomogeneities has remained unknown. In the present work the amount of energy stored in a density gradient is calculated for several specific density profiles in a cylindric configuration. This is of practical importance for drift wave instability in various plasmas, and in particular in its application in models dealing with the heating of solar corona because the instability is accompanied with stochastic heating, so the energy contained in inhomogeneity is effectively transformed into heat. It is shown that even for a rather moderate increase of the density at the axis in magnetic structures in the corona by a factor 1.5 or 3, the amount of excess energy per unit volume stored in such a density gradient becomes several orders of magnitude greater than the amount of total energy losses per unit ...

Vranjes, J

2015-01-01T23:59:59.000Z

125

A linear helicon plasma device with controllable magnetic field gradient  

SciTech Connect (OSTI)

Current free double layers (CFDLs) are localized potential structures having spatial dimensions - Debye lengths and potential drops of more than local electron temperature across them. CFDLs do not need a current for them to be sustained and hence they differ from the current driven double layers. Helicon antenna produced plasmas in an expanded chamber along with an expanding magnetic field have shown the existence of CFDL near the expansion region. A helicon plasma device has been designed, fabricated, and installed in the Institute for Plasma Research, India to study the role of maximum magnetic field gradient as well as its location with respect to the geometrical expansion region of the chamber in CFDL formation. The special feature of this machine consisting of two chambers of different radii is its capability of producing different magnetic field gradients near the physical boundary between the two chambers either by changing current in one particular coil in the direction opposite to that in other coils and/or by varying the position of this particular coil. Although, the machine is primarily designed for CFDL experiments, it is also capable of carrying out many basic plasma physics experiments such as wave propagation, wave coupling, and plasma instabilities in a varying magnetic field topology. In this paper, we will present the details of the machine construction, its specialties, and some preliminary results about the production and characterization of helicon plasma in this machine.

Barada, Kshitish K.; Chattopadhyay, P. K.; Ghosh, J.; Kumar, Sunil; Saxena, Y. C. [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428 (India)

2012-06-15T23:59:59.000Z

126

Hierarchically deflated conjugate gradient  

E-Print Network [OSTI]

We present a multi-level algorithm for the solution of five dimensional chiral fermion formulations, including domain wall and Mobius Fermions. The algorithm operates on the red-black preconditioned Hermitian operator, and directly accelerates conjugate gradients on the normal equations. The coarse grid representation of this matrix is next-to-next-to-next-to-nearest neighbour and multiple algorithmic advances are introduced, which help minimise the overhead of the coarse grid. The treatment of the coarse grids is purely four dimensional, and the bulk of the coarse grid operations are nearest neighbour. The intrinsic cost of most of the coarse grid operations is therefore comparable to those for the Wilson case. We also document the implementation of this algorithm in the BAGEL/Bfm software package and report on the measured performance gains the algorithm brings to simulations at the physical point on IBM BlueGene/Q hardware.

P A Boyle

2014-02-11T23:59:59.000Z

127

Gradient Sliding for Composite Optimization  

E-Print Network [OSTI]

Noname manuscript No. (will be inserted by the editor). Gradient Sliding for Composite Optimization. Guanghui Lan the date of receipt and acceptance should ...

2014-06-11T23:59:59.000Z

128

Global energy gradients and size in colonial organisms: Worker mass and worker number  

E-Print Network [OSTI]

Global energy gradients and size in colonial organisms: Worker mass and worker number in ant size varies globally is a key challenge to ecology. Solar energy may shape gradients of body size by its effects on local temperature and net primary productivity (16­20). Rising global temperatures (21

Kaspari, Mike

129

Thermal well-test method  

DOE Patents [OSTI]

A well-test method involving injection of hot (or cold) water into a groundwater aquifer, or injecting cold water into a geothermal reservoir. By making temperature measurements at various depths in one or more observation wells, certain properties of the aquifer are determined. These properties, not obtainable from conventional well test procedures, include the permeability anisotropy, and layering in the aquifer, and in-situ thermal properties. The temperature measurements at various depths are obtained from thermistors mounted in the observation wells.

Tsang, Chin-Fu (Albany, CA); Doughty, Christine A. (Berkeley, CA)

1985-01-01T23:59:59.000Z

130

Quantum Well Thermoelectrics for Converting Waste Heat to Electricity  

SciTech Connect (OSTI)

Fabrication development of high efficiency quantum well (QW) thermoelectric continues with the P-type and N-type Si/Si{sub 80}Ge{sub 20} films with encouraging results. These films are fabricated on Si substrates and are being developed for low as well as high temperature operation. Both isothermal and gradient life testing are underway. One couple has achieved over 4000 hours at T{sub H} of 300 C and T{sub C} of 50 C with little or no degradation. Emphasis is now shifting towards couple and module design and fabrication, especially low resistance joining between N and P legs. These modules can be used in future energy conversion systems as well as for air conditioning.

Saeid Ghamaty

2007-04-01T23:59:59.000Z

131

Block-conjugate-gradient method  

SciTech Connect (OSTI)

It is shown that by using the block-conjugate-gradient method several, say {ital s}, columns of the inverse Kogut-Susskind fermion matrix can be found simultaneously, in less time than it would take to run the standard conjugate-gradient algorithm {ital s} times. The method improves in efficiency relative to the standard conjugate-gradient algorithm as the fermion mass is decreased and as the value of the coupling is pushed to its limit before the finite-size effects become important. Thus it is potentially useful for measuring propagators in large lattice-gauge-theory calculations of the particle spectrum.

McCarthy, J.F. (Department of Physics, Indiana University, Bloomington, Indiana 47405 (US))

1989-09-15T23:59:59.000Z

132

High field gradient particle accelerator  

DOE Patents [OSTI]

A high electric field gradient electron accelerator utilizing short duration, microwave radiation, and capable of operating at high field gradients for high energy physics applications or at reduced electric field gradients for high average current intermediate energy accelerator applications is disclosed. Particles are accelerated in a smooth bore, periodic undulating waveguide, wherein the period is so selected that the particles slip an integral number of cycles of the r.f. wave every period of the structure. This phase step of the particles produces substantially continuous acceleration in a traveling wave without transverse magnetic or other guide means for the particle. 10 figs.

Nation, J.A.; Greenwald, S.

1989-05-30T23:59:59.000Z

133

High field gradient particle accelerator  

DOE Patents [OSTI]

A high electric field gradient electron accelerator utilizing short duration, microwave radiation, and capable of operating at high field gradients for high energy physics applications or at reduced electric field gradients for high average current intermediate energy accelerator applications. Particles are accelerated in a smooth bore, periodic undulating waveguide, wherein the period is so selected that the particles slip an integral number of cycles of the r.f. wave every period of the structure. This phase step of the particles produces substantially continuous acceleration in a traveling wave without transverse magnetic or other guide means for the particle.

Nation, John A. (Ithaca, NY); Greenwald, Shlomo (Haifa, IL)

1989-01-01T23:59:59.000Z

134

Thermal indicator for wells  

DOE Patents [OSTI]

Minute durable plate-like thermal indicators are employed for precision measuring static and dynamic temperatures of well drilling fluids. The indicators are small enough and sufficiently durable to be circulated in the well with drilling fluids during the drilling operation. The indicators include a heat resistant indicating layer, a coacting meltable solid component and a retainer body which serves to unitize each indicator and which may carry permanent indicator identifying indicia. The indicators are recovered from the drilling fluid at ground level by known techniques.

Gaven, Jr., Joseph V. (Oakton, VA); Bak, Chan S. (Newbury Park, CA)

1983-01-01T23:59:59.000Z

135

A Spectral Conjugate Gradient Method for Unconstrained Optimization  

SciTech Connect (OSTI)

A family of scaled conjugate gradient algorithms for large-scale unconstrained minimization is defined. The Perry, the Polak-Ribiere and the Fletcher-Reeves formulae are compared using a spectral scaling derived from Raydan's spectral gradient optimization method. The best combination of formula, scaling and initial choice of step-length is compared against well known algorithms using a classical set of problems. An additional comparison involving an ill-conditioned estimation problem in Optics is presented.

Birgin, E. G. [Department of Computer Science, IME-USP, University of Sao Paulo, Rua do Matao, 1010 - Cidade Universitaria, 05508-900 Sao Paulo SP (Brazil)], E-mail: egbirgin@ime.usp.br; Martinez, J. M. [Department of Applied Mathematics, IMECC-UNICAMP, University of Campinas, CP 6065, 13081-970 Campinas SP (Brazil)], E-mail: martinez@ime.unicamp.br

2001-07-01T23:59:59.000Z

136

Fully Coupled Well Models for Fluid Injection and Production  

SciTech Connect (OSTI)

Wells are the primary engineered component of geologic sequestration systems with deep subsurface reservoirs. Wells provide a conduit for injecting greenhouse gases and producing reservoirs fluids, such as brines, natural gas, and crude oil, depending on the target reservoir. Well trajectories, well pressures, and fluid flow rates are parameters over which well engineers and operators have control during the geologic sequestration process. Current drilling practices provided well engineers flexibility in designing well trajectories and controlling screened intervals. Injection pressures and fluids can be used to purposely fracture the reservoir formation or to purposely prevent fracturing. Numerical simulation of geologic sequestration processes involves the solution of multifluid transport equations within heterogeneous geologic media. These equations that mathematically describe the flow of fluid through the reservoir formation are nonlinear in form, requiring linearization techniques to resolve. In actual geologic settings fluid exchange between a well and reservoir is a function of local pressure gradients, fluid saturations, and formation characteristics. In numerical simulators fluid exchange between a well and reservoir can be specified using a spectrum of approaches that vary from totally ignoring the reservoir conditions to fully considering reservoir conditions and well processes. Well models are a numerical simulation approach that account for local conditions and gradients in the exchange of fluids between the well and reservoir. As with the mathematical equations that describe fluid flow in the reservoir, variation in fluid properties with temperature and pressure yield nonlinearities in the mathematical equations that describe fluid flow within the well. To numerically simulate the fluid exchange between a well and reservoir the two systems of nonlinear multifluid flow equations must be resolved. The spectrum of numerical approaches for resolving these equations varies from zero coupling to full coupling. In this paper we describe a fully coupled solution approach for well model that allows for a flexible well trajectory and screened interval within a structured hexahedral computational grid. In this scheme the nonlinear well equations have been fully integrated into the Jacobian matrix for the reservoir conservation equations, minimizing the matrix bandwidth.

White, Mark D.; Bacon, Diana H.; White, Signe K.; Zhang, Z. F.

2013-08-05T23:59:59.000Z

137

CONJUGATE GRADIENT WITH SUBSPACE OPTIMIZATION 1 ...  

E-Print Network [OSTI]

last update. Unlike some other conjugate gradient methods, our algorithm attains a theoretical ... The method of conjugate gradients (CG) was introduced by.

2011-12-25T23:59:59.000Z

138

Thermal well-test method  

DOE Patents [OSTI]

A well-test method involving injection of hot (or cold) water into a groundwater aquifer, or injecting cold water into a geothermal reservoir is disclosed. By making temperature measurements at various depths in one or more observation wells, certain properties of the aquifer are determined. These properties, not obtainable from conventional well test procedures, include the permeability anisotropy, and layering in the aquifer, and in-situ thermal properties. The temperature measurements at various depths are obtained from thermistors mounted in the observation wells.

Tsang, C.F.; Doughty, C.A.

1984-02-24T23:59:59.000Z

139

Geothermal Resource/Reservoir Investigations Based on Heat Flow and Thermal Gradient Data for the United States  

SciTech Connect (OSTI)

Several activities related to geothermal resources in the western United States are described in this report. A database of geothermal site-specific thermal gradient and heat flow results from individual exploration wells in the western US has been assembled. Extensive temperature gradient and heat flow exploration data from the active exploration of the 1970's and 1980's were collected, compiled, and synthesized, emphasizing previously unavailable company data. Examples of the use and applications of the database are described. The database and results are available on the world wide web. In this report numerical models are used to establish basic qualitative relationships between structure, heat input, and permeability distribution, and the resulting geothermal system. A series of steady state, two-dimensional numerical models evaluate the effect of permeability and structural variations on an idealized, generic Basin and Range geothermal system and the results are described.

D. D. Blackwell; K. W. Wisian; M. C. Richards; J. L. Steele

2000-04-01T23:59:59.000Z

140

Gas Exchange, Partial Pressure Gradients,  

E-Print Network [OSTI]

Gas Exchange, Partial Pressure Gradients, and the Oxygen Window Johnny E. Brian, Jr., M of circulatory and gas transport physiology, and the best place to start is with normobaric physiology. LIFE affect the precise gas exchange occurring in individual areas of the lungs and body tissues. To make

Riba Sagarra, Jaume

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Solid state electron-hopping transport and frozen concentration gradients in a mixed valent viologen-tetraethylene oxide copolymer  

SciTech Connect (OSTI)

This paper describes electrochemistry and electron-hopping dynamics for a novel viologen-based redox polymer (poly-V{sup 2+}) formed from the copolymerization of tetraethylene glycol di-p-tosylate and 4,4{prime}-bipyridine. Current-potential responses and electron-hopping (i.e., self-exchange) rates have been measured for mixed valent films of poly-V{sup 2+} on interdigitated array electrodes contacted by tetrahydrofuran/acetonitrile/tetrabutylammonium perchlorate electrolyte solution and as dry mixed valent films in vacuum or dry nitrogen. Electron transfer rates vary with the mixed valency composition of poly-V{sup 2+/+} films (judging film composition from the electrolysis potential with the Nernst equation) according to bimolecular reaction theory for solvent-wetted but less well for dry films. Current-potential characteristics are also reported for mixed valent films that contain concentration gradients of the poly-V{sup 2+} and poly-V{sup +} redox states, which we attempt to freeze into place by drying the film under a gradient-generating potential bias so as to immobilize the film`s counterions. Current transients at room and reduced (-30{degree}C) temperature show that the room-temperature responses of films containing concentration gradients are sensitive to small changes in poly-V{sup 2+/+} oxidation state at the electrode/polymer interfaces. 24 refs., 9 figs., 1 tab.

Terrill, R.H.; Hutchison, J.E.; Murray, R.W. [Univ. of North Carolina, Chapel Hill, NC (United States)] [Univ. of North Carolina, Chapel Hill, NC (United States)

1997-02-27T23:59:59.000Z

142

Scaling limits for gradient systems in random environment  

E-Print Network [OSTI]

For interacting particle systems that satisfies the gradient condition, the hydrodynamic limit and the equilibrium fluctuations are well known. We prove that under the presence of a symmetric random environment, these scaling limits also hold for almost every choice of the environment, with homogenized coefficients that does not depend on the particular realization of the random environment.

P. Goncalves; M. D. Jara

2007-02-17T23:59:59.000Z

143

GEOTHERMAL GRADIENT DATA FOR UTAH Robert E. Blackett  

E-Print Network [OSTI]

GEOTHERMAL GRADIENT DATA FOR UTAH by Robert E. Blackett February 2004 UTAH GEOLOGICAL SURVEY ­ 1:750,000 scale map, showing geology; thermal wells, springs, and geothermal areas; and locations available sources including the Southern Methodist University Geothermal Laboratory, U.S. Geological Survey

Laughlin, Robert B.

144

Novel concepts in weld science: Role of gradients and composite structure. Final report  

SciTech Connect (OSTI)

The effects of compositional and microstructural gradients on weld metal and simulated weld metal properties were evaluated in this multi-part study. The results obtained on single phase solid solution systems were used as a basis for a fundamental study of the effects of compositional gradients on crack growth, both at low temperatures, in fatigue and at high temperatures during creep. Methods to physically simulate gradients in weld metals with roll bonded laminate composites were applied to analyses of ferrite-austenite and ferrite-sigma-austenite multiphase systems. Finally, results of the physical simulation analyses were utilized to predict the effects of weld process parameters on weld metal properties.

Matlock, D.K.; Olson, D.L.

1994-03-01T23:59:59.000Z

145

Gradient Navigation Model for Pedestrian Dynamics  

E-Print Network [OSTI]

We present a new microscopic ODE-based model for pedestrian dynamics: the Gradient Navigation Model. The model uses a superposition of gradients of distance functions to directly change the direction of the velocity vector. The velocity is then integrated to obtain the location. The approach differs fundamentally from force based models needing only three equations to derive the ODE system, as opposed to four in, e.g., the Social Force Model. Also, as a result, pedestrians are no longer subject to inertia. Several other advantages ensue: Model induced oscillations are avoided completely since no actual forces are present. The derivatives in the equations of motion are smooth and therefore allow the use of fast and accurate high order numerical integrators. At the same time, existence and uniqueness of the solution to the ODE system follow almost directly from the smoothness properties. In addition, we introduce a method to calibrate parameters by theoretical arguments based on empirically validated assumptions rather than by numerical tests. These parameters, combined with the accurate integration, yield simulation results with no collisions of pedestrians. Several empirically observed system phenomena emerge without the need to recalibrate the parameter set for each scenario: obstacle avoidance, lane formation, stop-and-go waves and congestion at bottlenecks. The density evolution in the latter is shown to be quantitatively close to controlled experiments. Likewise, we observe a dependence of the crowd velocity on the local density that compares well with benchmark fundamental diagrams.

Felix Dietrich; Gerta Köster

2014-05-14T23:59:59.000Z

146

Conjugate Gradient Algorithms Using Multiple Recursions  

E-Print Network [OSTI]

of Colorado Much is already known about when a conjugate gradient method can be implemented with short and sufficient conditions on the iteration matrix A, in order for a conjugate gradient method to be implemented that the conjugate gradient method for unitary and shifted unitary matrices can be implemented using a single short

147

An Introduction to the Conjugate Gradient Method  

E-Print Network [OSTI]

An Introduction to the Conjugate Gradient Method Without the Agonizing Pain Edition 11 4 Jonathan Abstract The Conjugate Gradient Method is the most prominent iterative method for solving sparse systems, the Conjugate Gradient Method is a composite of simple, elegant ideas that almost anyone can understand

Zhang, Yi

148

An Introduction to the Conjugate Gradient Method  

E-Print Network [OSTI]

An Introduction to the Conjugate Gradient Method Without the Agonizing Pain Edition 1 1 4 Jonathan Abstract The Conjugate Gradient Method is the most prominent iterative method for solving sparse systems, the Conjugate Gradient Method is a composite of simple, elegant ideas that almost anyone can understand

Shewchuk, Jonathan

149

Porting the NAS-NPB Conjugate Gradient  

E-Print Network [OSTI]

.kr/Center_for_Manycore_Programming/SNU_NPB_Suite.html NPB Benchmarks #12;! "A conjugate gradient method is used to compute an approximation to the smallestPorting the NAS-NPB Conjugate Gradient Benchmark to CUDA NVIDIA Corporation #12;Outline ! Overview coding methodologies and architectures. ! Suite of benchmarks: ! Integer Sort ! Conjugate Gradient ! CFD

Crawford, T. Daniel

150

Accurate conjugate gradient methods for shifted systems  

E-Print Network [OSTI]

Accurate conjugate gradient methods for shifted systems by Jasper van den Eshof and Gerard L. G CONJUGATE GRADIENT METHODS FOR SHIFTED SYSTEMS JASPER VAN DEN ESHOF AND GERARD L. G. SLEIJPEN Abstract We present an efficient and accurate variant of the conjugate gradient method for solving families of shifted

Sleijpen, Gerard

151

A parallel scaled conjugate-gradient  

E-Print Network [OSTI]

. The scaled conjugate- gradient method is a powerful technique for solving large sparse linear systems for form-factor computation. Key words: Gathering radiosity -- Scaled conjugate-gradient method -- Parallel, the Gauss--Jacobi (GJ) method is used in the solution phase. The scaled conjugate-gradient (SCG) method

Aykanat, Cevdet

152

An Introduction to the Conjugate Gradient Method  

E-Print Network [OSTI]

An Introduction to the Conjugate Gradient Method Without the Agonizing Pain Jonathan Richard 15213 Abstract The Conjugate Gradient Method is the most prominent iterative method for solving sparse the mumblings of their forebears. Nevertheless, the Conjugate Gradient Method is a composite of simple, elegant

153

Accurate conjugate gradient methods for shifted systems  

E-Print Network [OSTI]

Accurate conjugate gradient methods for shifted systems by Jasper van den Eshof and Gerard L. G CONJUGATE GRADIENT METHODS FOR SHIFTED SYSTEMS JASPER VAN DEN ESHOF # AND GERARD L. G. SLEIJPEN # Abstract We present an e#cient and accurate variant of the conjugate gradient method for solving families

Sleijpen, Gerard

154

Bayesian Policy Gradient and Actor-Critic Algorithms Bayesian Policy Gradient and Actor-Critic Algorithms  

E-Print Network [OSTI]

Bayesian Policy Gradient and Actor-Critic Algorithms Bayesian Policy Gradient and Actor Yaakov Engel yakiengel@gmail.com Editor: Abstract Policy gradient methods are reinforcement learning algorithms that adapt a param- eterized policy by following a performance gradient estimate. Many

Paris-Sud XI, Université de

155

Field Investigations And Temperature-Gradient Drilling At Marine...  

Open Energy Info (EERE)

Drilling At Marine Corps Air-Ground Combat Center (Mcagcc), Twenty-Nine Palms, Ca Abstract The U.S. Navy's Geothermal Program Office (GPO) has been conducting geothermal...

156

Field Investigations And Temperature-Gradient Drilling At Marine Corps  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision has beenFfe2fb55-352f-473b-a2dd-50ae8b27f0a6 NoSan Leandro,LawFEMAProjectExpressFeltonAir-Ground Combat

157

Geology and Temperature Gradient Surveys Blue Mountain Geothermal  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision has beenFfe2fb55-352f-473b-a2dd-50ae8b27f0a6TheoreticalFuelCellGemini SolarAssetsofLane:Discovery,

158

Computer program to analyze multipass pressure-temperature-spinner surveys  

SciTech Connect (OSTI)

A computer program has been developed to analyze multipass pressure-temperature-spinner surveys and summarize the data in graphical form on two plots: (1) an overlay of spinner passes along with a fluid velocity profile calculated from the spinner and (2) an overlay of pressure, pressure gradient, and temperature profiles from each pass. The program has been written using SmartWare II Software. Fluid velocity is calculated for each data point using a cross-plot of tool speed and spinner counts to account for changing flow conditions in the wellbore. The program has been used successfully to analyze spinner surveys run in geothermal wells with two-phase flashing flow.

Spielman, Paul

1994-01-20T23:59:59.000Z

159

Shape reconstruction from gradient data  

SciTech Connect (OSTI)

We present a generalized method for reconstructing the shape of an object from measured gradient data. A certain class of optical sensors does not measure the shape of an object but rather its local slope. These sensors display several advantages, including high information efficiency, sensitivity, and robustness. For many applications, however, it is necessary to acquire the shape, which must be calculated from the slopes by numerical integration. Existing integration techniques show drawbacks that render them unusable in many cases. Our method is based on an approximation employing radial basis functions. It can be applied to irregularly sampled, noisy, and incomplete data, and it reconstructs surfaces both locally and globally with high accuracy.

Ettl, Svenja; Kaminski, Juergen; Knauer, Markus C.; Haeusler, Gerd

2008-04-20T23:59:59.000Z

160

Well control procedures for extended reach wells  

E-Print Network [OSTI]

been found to be critical to the success of ERD are torque and drag, drillstring design, wellbore stability, hole cleaning, casing design, directional drilling optimization, drilling dynamics and rig sizing.4 Other technologies of vital importance... are the use of rotary steerable systems (RSS) together with measurement while drilling (MWD) and logging while drilling (LWD) to geosteer the well into the geological target.5 Many of the wells drilled at Wytch Farm would not have been possible to drill...

Gjorv, Bjorn

2004-09-30T23:59:59.000Z

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Compensated geothermal gradient: new map of old data  

SciTech Connect (OSTI)

Bottom-hole temperature measurement is one of the oldest forms of downhole information acquired by the oil industry. Old and new geothermal maps that are based on these measurements have invariably been drawn with an assumed constant or average ground surface temperature over the mapped areas. However, near ground-surface equilibrium temperature is a variable rather than a constant over any region; therefore, old and current geothermal gradient mapping methods give a false impression of the true thermal level of subsurface strata, and may lead to erroneous results of temperature-based calculations, such as the TTI. In this paper, a geothermal mapping method is presented in which extrapolated surface temperature is coupled with the corresponding geothermal gradient over the mapped area. The method was tested on areas in the Middle East and Africa. Results indicate that it is especially effective in delineating loci of vertical geothermal heat flux carried upwards by ascending subsurface fluids; such areas are preferential sites for hydrocarbon entrapment, especially in young sedimentary basins where migration is still in progress.

Ibrahim, M.W.

1986-05-01T23:59:59.000Z

162

Atom interferometric techniques for measuring gravitational acceleration and constant magnetic field gradients  

E-Print Network [OSTI]

We discuss two techniques for probing the effects of a homogeneous force acting on cold atoms, such as that due to gravity or a constant magnetic field gradient, using grating echo-type atom interferometers. A comprehensive theoretical description of signals generated by both two-pulse and three-pulse interferometers, accounting for magnetic sub-levels in the atomic ground state, is shown to agree with experimental results. Laser-cooled samples of $^{85}$Rb with temperatures as low as 2.4 $\\mu$K have been achieved in a relatively large glass cell with well-suppressed magnetic fields. Using transit time limited interferometer signals, we demonstrate sensitivity to externally applied magnetic gradients as small as $\\sim 4$ mG/cm. With these timescales we estimate that precision measurements of the gravitational acceleration, $g$, are possible with both the two-pulse and three-pulse echo interferometers. Whereas the two-pulse signal is a position-sensitive technique to measure the absolute value of $g$, the thre...

Barrett, B

2011-01-01T23:59:59.000Z

163

Optimization Online - A Nonlinear Conjugate Gradient Algorithm ...  

E-Print Network [OSTI]

Jun 28, 2011 ... Abstract: In this paper, we seek the conjugate gradient direction closest to the direction of the scaled memoryless BFGS method and propose a ...

Yu-Hong Dai

2011-06-28T23:59:59.000Z

164

A GLOBALLY CONVERGENT MODIFIED CONJUGATE-GRADIENT ...  

E-Print Network [OSTI]

based upon applying modified variants of either PCG or Lanczos method to the sys- ... conjugate-gradient based strategies for optimizing a constrained ...

2009-10-01T23:59:59.000Z

165

Optimization Online - An Accelerated Proximal Coordinate Gradient ...  

E-Print Network [OSTI]

Jul 7, 2014 ... An Accelerated Proximal Coordinate Gradient Method and its Application to Regularized Empirical Risk Minimization. Qihang Lin(qihang-lin ...

Qihang Lin

2014-07-07T23:59:59.000Z

166

Optimization of synchronization in gradient clustered networks  

E-Print Network [OSTI]

We consider complex clustered networks with a gradient structure, where sizes of the clusters are distributed unevenly. Such networks describe more closely actual networks in biophysical systems and in technological applications than previous models. Theoretical analysis predicts that the network synchronizability can be optimized by the strength of the gradient field but only when the gradient field points from large to small clusters. A remarkable finding is that, if the gradient field is sufficiently strong, synchronizability of the network is mainly determined by the properties of the subnetworks in the two largest clusters. These results are verified by numerical eigenvalue analysis and by direct simulation of synchronization dynamics on coupled-oscillator networks.

Xingang Wang; Liang Huang; Ying-Cheng Lai; Choy Heng Lai

2007-11-23T23:59:59.000Z

167

Regulations of Wells (Florida)  

Broader source: Energy.gov [DOE]

The Department of Environmental Protection regulates the construction, repair, and abandonment of wells, as well as the persons and businesses undertaking such practices. Governing boards of water...

168

Groundwater and Wells (Nebraska)  

Broader source: Energy.gov [DOE]

This section describes regulations relating to groundwater protection, water wells, and water withdrawals, and requires the registration of all water wells in the state.

169

Death Valley Lower Carbonate Aquifer Monitoring Program Wells Down Gradient of the Proposed Yucca Mountain Nuclear Waste Repository, U. S. Department of Energy Grant DE-RW0000233 2010 Project Report, prepared by The Hydrodynamics Group, LLC for Inyo County Yucca Mountain Repository Assessment Office  

SciTech Connect (OSTI)

Inyo County completed the first year of the U.S. Department of Energy Grant Agreement No. DE-RW0000233. This report presents the results of research conducted within this Grant agreement in the context of Inyo County's Yucca Mountain oversight program goals and objectives. The Hydrodynamics Group, LLC prepared this report for Inyo County Yucca Mountain Repository Assessment Office. The overall goal of Inyo County's Yucca Mountain research program is the evaluation of far-field issues related to potential transport, by ground water, of radionuclide into Inyo County, including Death Valley, and the evaluation of a connection between the Lower Carbonate Aquifer (LCA) and the biosphere. Data collected within the Grant is included in interpretive illustrations and discussions of the results of our analysis. The centeral elements of this Grant prgoram was the drilling of exploratory wells, geophysical surveys, geological mapping of the Southern Funeral Mountain Range. The cullimination of this research was 1) a numerical ground water model of the Southern Funeral Mountain Range demonstrating the potential of a hydraulic connection between the LCA and the major springs in the Furnace Creek area of Death Valley, and 2) a numerical ground water model of the Amargosa Valley to evaluate the potential for radionuclide transport from Yucca Mountain to Inyo County, California. The report provides a description of research and activities performed by The Hydrodynamics Group, LLC on behalf of Inyo County, and copies of key work products in attachments to this report.

King, Michael J; Bredehoeft, John D., Dr.

2010-09-03T23:59:59.000Z

170

Plugging Abandoned Water Wells  

E-Print Network [OSTI]

. It is recommended that before you begin the process of plugging an aban- doned well that you seek advice from your local groundwater conservation district, a licensed water well driller in your area, or the Water Well Drillers Program with the Texas Department... hire a licensed water well driller or pump installer to seal and plug an abandoned well. Well contractors have the equipment and an understanding of soil condi- tions to determine how a well should be properly plugged. How can you take care...

Lesikar, Bruce J.

2002-02-28T23:59:59.000Z

171

Geothermal Well and Heat Flow Data for the United States (Southern Methodist University (SMU) Geothermal Laboratory)  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

Southern Methodist University makes two databases and several detailed maps available. The Regional Heat Flow Database for the United States contains information on primarily regional or background wells that determine the heat flow for the United States; temperature gradients and conductivity are used to generate heat flow measurements. Information on geology of the location, porosity, thermal conductivity, water table depth, etc. are also included when known. There are usually three data files for each state or region. The first files were generated in 1989 for the data base creating the Decade of North America Geology (DNAG) Geothermal Map. The second set is from 1996 when the data base was officially updated for the Department of Energy. The third set is from 1999 when the Western U.S. High Temperature Geothermal data base was completed. As new data is received, the files continue to be updated. The second major resource is the Western Geothermal Areas Database, a database of over 5000 wells in primarily high temperature geothermal areas from the Rockies to the Pacific Ocean. The majority of the data are from company documents, well logs, and publications with drilling dates ranging from 1960 to 2000. Many of the wells were not previously accessible to the public. Users will need to register, but will then have free, open access to the databases. The contents of each database can be viewed and downloaded as Excel spreadsheets. See also the heat flow maps at http://www.smu.edu/geothermal/heatflow/heatflow.htm

Blackwell, D.D. and others

172

Approximate error conjugation gradient minimization methods  

DOE Patents [OSTI]

In one embodiment, a method includes selecting a subset of rays from a set of all rays to use in an error calculation for a constrained conjugate gradient minimization problem, calculating an approximate error using the subset of rays, and calculating a minimum in a conjugate gradient direction based on the approximate error. In another embodiment, a system includes a processor for executing logic, logic for selecting a subset of rays from a set of all rays to use in an error calculation for a constrained conjugate gradient minimization problem, logic for calculating an approximate error using the subset of rays, and logic for calculating a minimum in a conjugate gradient direction based on the approximate error. In other embodiments, computer program products, methods, and systems are described capable of using approximate error in constrained conjugate gradient minimization problems.

Kallman, Jeffrey S

2013-05-21T23:59:59.000Z

173

Horizontal well IPR calculations  

SciTech Connect (OSTI)

This paper presents the calculation of near-wellbore skin and non-Darcy flow coefficient for horizontal wells based on whether the well is drilled in an underbalanced or overbalanced condition, whether the well is completed openhole, with a slotted liner, or cased, and on the number of shots per foot and phasing for cased wells. The inclusion of mechanical skin and the non-Darcy flow coefficient in previously published horizontal well equations is presented and a comparison between these equations is given. In addition, both analytical and numerical solutions for horizontal wells with skin and non-Darcy flow are presented for comparison.

Thomas, L.K.; Todd, B.J.; Evans, C.E.; Pierson, R.G.

1996-12-31T23:59:59.000Z

174

Underground Wells (Oklahoma)  

Broader source: Energy.gov [DOE]

Class I, III, IV and V injection wells require a permit issued by the Executive Director of the Department of Environmental Quality; Class V injection wells utilized in the remediation of...

175

Surface Temperature and Surface-Layer Turbulence in a Convective Boundary Layer  

E-Print Network [OSTI]

The vertical gradient of horizontal wind-speed was estimateda larger vertical gradient of horizontal wind-speed in thewind speed, direction, temperature, humidity up to 20 km with a vertical

Garai, Anirban; Pardyjak, Eric; Steeneveld, Gert-Jan; Kleissl, Jan

2013-01-01T23:59:59.000Z

176

Characterization of Min-K TE-1400 Thermal Insulation (Two-Year Gradient Stress Relaxation Testing Update)  

SciTech Connect (OSTI)

Min-K 1400TE insulation material was characterized at Oak Ridge National Laboratory for use in structural applications under gradient temperature conditions. A previous report (ORNL/TM-2008/089) discusses the testing and results from the original three year duration of the project. This testing included compression testing to determine the effect of sample size and test specimen geometry on the compressive strength of Min-K, subsequent compression testing on cylindrical specimens to determine loading rates for stress relaxation testing, isothermal stress relaxation testing, and gradient stress relaxation testing. This report presents the results from the continuation of the gradient temperature stress relaxation testing and the resulting updated modeling.

Hemrick, James Gordon [ORNL; Lara-Curzio, Edgar [ORNL; King, James [ORNL

2009-09-01T23:59:59.000Z

177

Well drilling apparatus  

SciTech Connect (OSTI)

A drill rig for drilling wells having a derrick adapted to hold and lower a conductor string and drill pipe string. A support frame is fixed to the derrick to extend over the well to be drilled, and a rotary table, for holding and rotating drill pipe strings, is movably mounted thereon. The table is displaceable between an active position in alignment with the axis of the well and an inactive position laterally spaced therefrom. A drill pipe holder is movably mounted on the frame below the rotary table for displacement between a first position laterally of the axis of the well and a second position in alignment with the axis of the well. The rotary table and said drill pipe holder are displaced in opposition to each other, so that the rotary table may be removed from alignment with the axis of the well and said drill pipe string simultaneously held without removal from said well.

Prins, K.; Prins, R.K.

1982-09-28T23:59:59.000Z

178

Unique aspects of drilling and completing hot-dry-rock geothermal wells  

SciTech Connect (OSTI)

Drilling operations at the Fenton Hill Hot Dry Rock (HDR) Geothermal Test Site have led to numerous developments needed to solve the problems caused by a very harsh downhole environment. A pair of deep wells were drilled to approximately 15,000 ft (4.6 km); formation temperatures were in excess of 600/sup 0/F (300/sup 0/C). The wells were directionally drilled, inclined at 35/sup 0/, one above the other, in a direction orthogonal to the least principal stress field. The well site is near the flank of a young silicic composite volcano in the Jemez Mountains of northern New Mexico. The completion of this pair of wells is unique in reservoir development. The lower well was planned as a cold water injector which will be cooled by the introduced water from the static geothermal gradient to about 80/sup 0/F (25/sup 0/C). The upper well will be heated during production to over 500/sup 0/F (250/sup 0/C). The well pair is designed to perform as a closed loop heat-extraction system connected by hydraulic fractures with a vertical spacing of 1200 ft between the wells. These conditions strongly constrain the drilling technique, casing design, cement formulation, and cementing operations.

Carden, R.S.; Nicholson, R.W.; Pettitt, R.A.; Rowley, J.C.

1983-01-01T23:59:59.000Z

179

Time changes in gradient and observed winds  

E-Print Network [OSTI]

TIME CHANGES IN GRADIENT AND OBSERVED WINDS A Thesis by RONALD DALE CARLSON Submitted to the Graduate College of Texas A&M University in partial fulfillm=n of the requirement for the degree of MASTER OF SCIENCE MAY 1972 Major Subject...: Meteorology TIME CHANGES IN GRADIENT AND OBSERVED WINDS A Thesis by RONALD D. CARLSON Approved as to style and content by: (Chairman of Co , ee) (Member) (Member) May 1972 ABSTRACT Time Changes in Gradient and Observed Winds. (May 1972) Ronald Dale...

Carlson, Ronald Dale

1972-01-01T23:59:59.000Z

180

Measurement of thermodynamics using gradient flow  

E-Print Network [OSTI]

We analyze bulk thermodynamics and correlation functions of the energy-momentum tensor in pure Yang-Mills gauge theory using the energy-momentum tensor defined by the gradient flow and small flow time expansion. Our results on thermodynamic observables are consistent with those obtained by the conventional integral method. The analysis of the correlation function of total energy supports the energy conservation. It is also addressed that these analyses with gradient flow require less statistics compared with the previous methods. All these results suggest that the energy-momentum tensor can be successfully defined and observed on the lattice with moderate numerical costs with the gradient flow.

Masakiyo Kitazawa; Masayuki Asakawa; Tetsuo Hatsuda; Takumi Iritani; Etsuko Itou; Hiroshi Suzuki

2014-12-15T23:59:59.000Z

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Gradient Plasticity Model and its Implementation into MARMOT  

SciTech Connect (OSTI)

The influence of strain gradient on deformation behavior of nuclear structural materials, such as boby centered cubic (bcc) iron alloys has been investigated. We have developed and implemented a dislocation based strain gradient crystal plasticity material model. A mesoscale crystal plasticity model for inelastic deformation of metallic material, bcc steel, has been developed and implemented numerically. Continuum Dislocation Dynamics (CDD) with a novel constitutive law based on dislocation density evolution mechanisms was developed to investigate the deformation behaviors of single crystals, as well as polycrystalline materials by coupling CDD and crystal plasticity (CP). The dislocation density evolution law in this model is mechanism-based, with parameters measured from experiments or simulated with lower-length scale models, not an empirical law with parameters back-fitted from the flow curves.

Barker, Erin I.; Li, Dongsheng; Zbib, Hussein M.; Sun, Xin

2013-08-01T23:59:59.000Z

182

Thermal Gradient Holes At Salt Wells Area (Bureau of Land Management, 2009)  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revisionEnvReviewNonInvasiveExplorationUT-gTaguspark JumpDetective JumpInc., 2010) | Open EnergyEnergyEnergy| Open

183

THE MULTIGRID PRECONDITIONED CONJUGATE GRADIENT METHOD Osamu Tatebe  

E-Print Network [OSTI]

THE MULTIGRID PRECONDITIONED CONJUGATE GRADIENT METHOD Osamu Tatebe Department of Information Science University of Tokyo Tokyo, JAPAN SUMMARY A multigrid preconditioned conjugate gradient method iterations and the multigrid preconditioner is a desirable preconditioner of the conjugate gradient method. 1

184

Low-temperature geothermal assessment of the Santa Clara and Virgin River Valleys, Washington County, Utah  

SciTech Connect (OSTI)

Exploration techniques included the following: (1) a temperature survey of springs, (2) chemical analyses and calculated geothermometer temperatures of water samples collected from selected springs and wells, (3) chemical analyses and calculated geothermometer temperatures of spring and well water samples in the literature, (4) thermal gradients measured in accessible wells, and (5) geology. The highest water temperature recorded in the St. George basin is 42/sup 0/C at Pah Tempe Hot Springs. Additional spring temperatures higher than 20/sup 0/C are at Veyo Hot Spring, Washington hot pot, and Green Spring. The warmest well water in the study area is 40/sup 0/C in Middleton Wash. Additional warm well water (higher than 24.5/sup 0/C) is present north of St. George, north of Washington, southeast of St. George, and in Dameron Valley. The majority of the Na-K-Ca calculated reservoir temperatures range between 30/sup 0/ and 50/sup 0/C. Anomalous geothermometer temperatures were calculated for water from Pah Tempe and a number of locations in St. George and vicinity. In addition to the known thermal areas of Pah Tempe and Veyo Hot Spring, an area north of Washington and St. George is delineated in this study to have possible low-temperature geothermal potential.

Budding, K.E.; Sommer, S.N.

1986-01-01T23:59:59.000Z

185

Separation of carbon nanotubes in density gradients  

DOE Patents [OSTI]

The separation of single-walled carbon nanotubes (SWNTs), by chirality and/or diameter, using centrifugation of compositions of SWNTs in and surface active components in density gradient media.

Hersam, Mark C. (Evanston, IL); Stupp, Samuel I. (Chicago, IL); Arnold, Michael S. (Northbrook, IL)

2012-02-07T23:59:59.000Z

186

Separation of carbon nanotubes in density gradients  

DOE Patents [OSTI]

The separation of single-walled carbon nanotubes (SWNTs), by chirality and/or diameter, using centrifugation of compositions of SWNTs in and surface active components in density gradient media.

Hersam, Mark C. (Evanston, IL); Stupp, Samuel I. (Chicago, IL); Arnold, Michael S. (Northbrook, IL)

2010-02-16T23:59:59.000Z

187

A globally convergent modified conjugate-gradient line-search ...  

E-Print Network [OSTI]

Sep 23, 2009 ... Further, we provide a new variant of modified conjugate gradient algorithms ... optimization, trust region methods, conjugate gradient method.

Wenwen Zhou

2009-09-23T23:59:59.000Z

188

Conjugate gradient methods based on secant conditions that ...  

E-Print Network [OSTI]

Sep 28, 2011 ... (2001) proposed a conjugate gradient method based on the secant ... Recently, the conjugate gradient method is paid attention to as an ...

2011-09-28T23:59:59.000Z

189

An inexact accelerated proximal gradient method for large scale ...  

E-Print Network [OSTI]

projected gradient method, and usually has good practical performance on .... conditioned, the conjugate gradient (CG) method would have great difficulty in ...

2011-09-09T23:59:59.000Z

190

On the regularizing behavior of recent gradient methods in the ...  

E-Print Network [OSTI]

Jun 14, 2014 ... On the regularizing behavior of recent gradient methods in the ... can be competitive with the Conjugate Gradient (CG) method, since they are ...

Roberta De Asmundis

2014-06-14T23:59:59.000Z

191

a perry descent conjugate gradient method with restricted spectrum ...  

E-Print Network [OSTI]

A new nonlinear conjugate gradient method, based on Perry's ... Key words and phrases. large scale optimization, conjugate gradient method, descent property ...

2011-05-09T23:59:59.000Z

192

An efficient gradient method using the Yuan steplength  

E-Print Network [OSTI]

Abstract We propose a new gradient method for quadratic programming, named SDC, .... We note that although the Conjugate Gradient (CG) method is still the ...

2014-05-29T23:59:59.000Z

193

Comparative systems biology across an evolutionary gradient within...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

systems biology across an evolutionary gradient within the Shewanella genus . Comparative systems biology across an evolutionary gradient within the Shewanella genus . Abstract: To...

194

Gas flow to a barometric pumping well in a multilayer unsaturated Kehua You,1  

E-Print Network [OSTI]

Gas flow to a barometric pumping well in a multilayer unsaturated zone Kehua You,1 Hongbin Zhan,1. [1] When an open well is installed in an unsaturated zone, gas can flow between the subsurface and the well depending on the gas pressure gradient near the well. This well is called a barometric pumping

Zhan, Hongbin

195

ADVANCED CEMENTS FOR GEOTHERMAL WELLS  

SciTech Connect (OSTI)

Using the conventional well cements consisting of the calcium silicate hydrates (CaO-SiO{sub 2}-H{sub 2}O system) and calcium aluminum silicate hydrates (CaO-Al{sub 2}O{sub 3}-SiO{sub 2}-H{sub 2}O system) for the integrity of geothermal wells, the serious concern confronting the cementing industries was their poor performance in mechanically supporting the metallic well casing pipes and in mitigating the pipe's corrosion in very harsh geothermal reservoirs. These difficulties are particularly acute in two geological regions: One is the deep hot downhole area ({approx} 1700 m depth at temperatures of {approx} 320 C) that contains hyper saline water with high concentrations of CO{sub 2} (> 40,000 ppm) in conjunction with {approx} 100 ppm H{sub 2}S at a mild acid of pH {approx} 5.0; the other is the upper well region between the well's surface and {approx} 1000 m depth at temperatures up to 200 C. The specific environment of the latter region is characterized by highly concentrated H{sub 2}SO{sub 4} (pH < 1.5) brine containing at least 5000 ppm CO{sub 2}. When these conventional cements are emplaced in these harsh environments, their major shortcoming is their susceptibility to reactions with hot CO{sub 2} and H{sub 2}SO4, thereby causing their deterioration brought about by CO{sub 2}-catalyzed carbonation and acid-initiated erosion. Such degradation not only reduced rapidly the strength of cements, lowering the mechanical support of casing pipes, but also increased the extent of permeability of the brine through the cement layer, promoting the rate of the pipe's corrosion. Severely carbonated and acid eroded cements often impaired the integrity of a well in less than one year; in the worst cases, casings have collapsed within three months, leading to the need for costly and time-consuming repairs or redrilling operations. These were the reasons why the geothermal well drilling and cementing industries were concerned about using conventional well cements, and further their deterioration was a major impediment in expediting the development of geothermal energy resources.

SUGAMA,T.

2007-01-01T23:59:59.000Z

196

BUFFERED WELL FIELD OUTLINES  

U.S. Energy Information Administration (EIA) Indexed Site

drainage radii) ...see figure below. Copy the code into a new module. Inputs: In ArcMap, data frame named "Task 1" Well FC as first layer (layer 0). Output: Polygon feature class...

197

Shock Chlorination of Wells  

E-Print Network [OSTI]

Shock chlorination is a method of disinfecting a water well. This publication gives complete instructions for chlorinating with bleach or with dry chlorine. It is also available in Spanish as publication L-5441S...

McFarland, Mark L.; Dozier, Monty

2003-06-11T23:59:59.000Z

198

CONTINUOUS EDGE GRADIENT-BASED TEMPLATE MATCHING FOR ARTICULATED OBJECTS  

E-Print Network [OSTI]

template matching, deformable object detection, confidence map, edge feature, graphics hardware In this paper, we propose a novel edge gradient based template matching method for object detection. In contrast to other methods, ours does not perform any binarization or discretization during the online matching. This is facilitated by a new continuous edge gradient similarity measure. Its main components are a novel edge gradient operator, which is applied to query and template images, and the formulation as a convolution, which can be computed very efficiently in Fourier space. We compared our method to a state-of-the-art chamfer based matching method. The results demonstrate that our method is much more robust against weak edge response and yields much better confidence maps with fewer maxima that are also more significant. In addition, our method lends itself well to efficient implementation on GPUs: at a query image resolution of 320 × 256 and a template resolution of 80 × 80 we can generate about 330 confidence maps per second. 1

Daniel Mohr; Gabriel Zachmann

199

Solar rotation rate and its gradients during cycle 23  

E-Print Network [OSTI]

Available helioseismic data now span almost the entire solar activity cycle 23 making it possible to study solar-cycle related changes of the solar rotation rate in detail. In this paper we study how the solar rotation rate, in particular, the zonal flows change with time. In addition to the zonal flows that show a well known pattern in the solar convection zone, we also study changes in the radial and latitudinal gradients of the rotation rate, particularly in the shear layer that is present in the immediate sub-surface layers of the Sun. In the case of the zonal-flow pattern, we find that the band indicating fast rotating region close to the equator seems to have bifurcated around 2005. Our investigation of the rotation-rate gradients show that the relative variation in the rotation-rate gradients is about 20% or more of their average values, which is much larger than the relative variation in the rotation rate itself. These results can be used to test predictions of various solar dynamo models.

H. M. Antia; Sarbani Basu; S. M. Chitre

2008-05-22T23:59:59.000Z

200

Spacer for deep wells  

SciTech Connect (OSTI)

A spacer for use in a deep well that is to have a submersible pump situated downhole and with a string of tubing attached to the pump for delivering the pumped fluid. The pump is electrically driven, and power is supplied via an armored cable which parallels the string of tubing. Spacers are clamped to the cable and have the tubing running through an eccentrically located passage in each spacer. The outside dimensions of a spacer fit freely inside any casing in the well.

Klein, G. D.

1984-10-23T23:59:59.000Z

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

TitleA Spectroscopy Diagnostic of Plasma Gradients in ICF Imploded Cores  

E-Print Network [OSTI]

TitleA Spectroscopy Diagnostic of Plasma Gradients in ICF Imploded Cores I. Golovkin, R. Mancini, S to be a powerful diagnostic of spatially-averaged temperature and density plasma conditions at the collapse of ICF-broadened line shapes. The next step in the spectroscopy of imploded cores is the bracketing of core plasma

Louis, Sushil J.

202

Mountain Home Well - Photos  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

The Snake River Plain (SRP), Idaho, hosts potential geothermal resources due to elevated groundwater temperatures associated with the thermal anomaly Yellowstone-Snake River hotspot. Project HOTSPOT has coordinated international institutions and organizations to understand subsurface stratigraphy and assess geothermal potential. Over 5.9km of core were drilled from three boreholes within the SRP in an attempt to acquire continuous core documenting the volcanic and sedimentary record of the hotspot: (1) Kimama, (2) Kimberly, and (3) Mountain Home. The Mountain Home drill hole is located along the western plain and documents older basalts overlain by sediment. Data submitted by project collaborator Doug Schmitt, University of Alberta

Shervais, John

203

The gradient flow running coupling with twisted boundary conditions  

E-Print Network [OSTI]

We study the gradient flow for Yang-Mills theories with twisted boundary conditions. The perturbative behavior of the energy density $\\langle E(t)\\rangle$ is used to define a running coupling at a scale given by the linear size of the finite volume box. We compute the non-perturbative running of the pure gauge $SU(2)$ coupling constant and conclude that the technique is well suited for further applications due to the relatively mild cutoff effects of the step scaling function and the high numerical precision that can be achieved in lattice simulations. We also comment on the inclusion of matter fields.

A. Ramos

2014-09-04T23:59:59.000Z

204

Electric field gradient, generalized Sternheimer shieldings and electric field gradient polarizabilities by multiconfigurational SCF response  

E-Print Network [OSTI]

Electric field gradient, generalized Sternheimer shieldings and electric field gradient at the nuclei, the generalized Sternheimer shielding constants and the EFG electric dipole polarizabilities discussed by Egstro¨m and co-workers4 and recently in a more general way by Fowler and co-workers.5

Helgaker, Trygve

205

Ch. VII, Temperature, heat flow maps and temperature gradient holes | Open  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address: 160Benin:Energy Information on PV2009 | OpenCeradyne Inc Jump to:CerionEnergyEnergy

206

TOWARDS STOCHASTIC CONJUGATE GRADIENT METHODS Nicol N. Schraudolph Thore Graepel  

E-Print Network [OSTI]

TOWARDS STOCHASTIC CONJUGATE GRADIENT METHODS Nicol N. Schraudolph Thore Graepel schraudo of conjugate gradients provides a very effective way to optimize large, deterministic systems by gradient de. Here we explore a number of ways to adopt ideas from conjugate gradient in the stochastic setting

Schraudolph, Nicol N.

207

Relationship between gradient and EM steps in latent variable models.  

E-Print Network [OSTI]

includes random search, standard gradient­based algorithms, line search methods such as conjugate gradient to to first order method operat­ ing on the gradient of a locally reshaped likelihood function. DirectRelationship between gradient and EM steps in latent variable models. Ruslan Salakhutdinov Sam

Roweis, Sam

208

11 SOME PROPERTIES OF A NEW CONJUGATE GRADIENT METHOD  

E-Print Network [OSTI]

11 SOME PROPERTIES OF A NEW CONJUGATE GRADIENT METHOD Y. H. Dai and Y. Yuan State Key Laboratory@cc.ac.cn Abstract: It is proved that the new conjugate gradient method proposed by Dai and Yuan 5] produces problem minf(x) x 2 Rn (1.1) where f is smooth and its gradient g is available. Conjugate gradient methods

Yuan, Ya-xiang

209

Relationship between gradient and EM steps in latent variable models.  

E-Print Network [OSTI]

includes random search, standard gradient-based algorithms, line search methods such as conjugate gradient to to first order method operat- ing on the gradient of a locally reshaped likelihood function. DirectRelationship between gradient and EM steps in latent variable models. Ruslan Salakhutdinov Sam

Roweis, Sam

210

Electron transport and frozen concentration gradients in a mixed valent viologen molten salt  

SciTech Connect (OSTI)

This paper shows that electrolytically generated crossed concentration gradients of viologen (2+) and viologen (1+) in films of its mixed valent molten salt on interdigitated array electrodes can be thermally and stably frozen in place in the interelectrode gaps. A study is presented of properties of the gradient-containing films, as compared to films that are non-mixed valent (V{sup 2+}) or that are mixed valent but lack concentration gradients. Comparisons of charge transport measurements show that the 2-5 {mu}m wide concentration gradients are persistent in the molten salt at lowered temperatures, where ionic motions are quenched relative to electron hopping as shown by differences in conductivity between mixed valent and non-mixed valent films as the temperature is lowered from +50 to -70{degree}C. Differences in the magnitude and shape of high-field current-voltage curves taken from mixed valent nongradient and V{sup 2+}/V{sup +} gradient-containing samples are interpreted with an electron-hopping model that includes a parameter for kinetic dispersity. Differences between the capacitance of the mixed valent and non-mixed valent phase of the viologen molten salt are consistent with the formation of an electronic space charge at the metal/redox conductor interface. 18 refs., 8 figs., 1 tab.

Terrill, R.H.; Hatazawa, Tsuyonobu; Murray, R.W. [Univ. of North Carolina, Chapel Hill, NC (United States)

1995-11-09T23:59:59.000Z

211

Conjugate gradient algorithms using multiple recursions  

SciTech Connect (OSTI)

Much is already known about when a conjugate gradient method can be implemented with short recursions for the direction vectors. The work done in 1984 by Faber and Manteuffel gave necessary and sufficient conditions on the iteration matrix A, in order for a conjugate gradient method to be implemented with a single recursion of a certain form. However, this form does not take into account all possible recursions. This became evident when Jagels and Reichel used an algorithm of Gragg for unitary matrices to demonstrate that the class of matrices for which a practical conjugate gradient algorithm exists can be extended to include unitary and shifted unitary matrices. The implementation uses short double recursions for the direction vectors. This motivates the study of multiple recursion algorithms.

Barth, T.; Manteuffel, T.

1996-12-31T23:59:59.000Z

212

Decontaminating Flooded Wells  

E-Print Network [OSTI]

ER-011 6-06 Mark L. McFarland, Associate Professor and Extension Water Resources Specialist; Diane E. Boellstorff, Program Specialist Water Quality; Tony L. Provin, Associate Professor and Extension Soil Chemist; Monty C. Dozier, Assistant... and local hospitals may also test water samples for bacteria. The cost of the test ranges from $8 to $30, depending on the lab. Well disinfection does not eliminate hydrocarbons (fuels, oils), pesticides, heavy metals or other types of nonbiological...

Boellstorff, Diana; Dozier, Monty; Provin, Tony; Dictson, Nikkoal; McFarland, Mark L.

2005-09-30T23:59:59.000Z

213

17 GHz High Gradient Accelerator Research  

SciTech Connect (OSTI)

This is a report on the MIT High Gradient Accelerator Research program which has included: Operation of the 17 GHz, 25 MeV MIT/Haimson Research Corp. electron accelerator at MIT, the highest frequency, stand-alone accelerator in the world; collaboration with members of the US High Gradient Collaboration, including the design and test of novel structures at SLAC at 11.4 GHz; the design, construction and testing of photonic bandgap structures, including metallic and dielectric structures; the investigation of the wakefields in novel structures; and the training of the next generation of graduate students and postdoctoral associates in accelerator physics.

Temkin, Richard J. [MIT] [MIT; Shapiro, Michael A. [MIT] [MIT

2013-07-10T23:59:59.000Z

214

High-pressure liquid chromatographic gradient mixer  

DOE Patents [OSTI]

A gradient mixer effects the continuous mixing of any two miscible solvents without excessive decay or dispersion of the resultant isocratic effluent or of a linear or exponential gradient. The two solvents are fed under low or high pressure by means of two high performance liquid chromatographic pumps. The mixer comprises a series of ultra-low dead volume stainless steel tubes and low dead volume chambers. The two solvent streams impinge head-on at high fluxes. This initial nonhomogeneous mixture is then passed through a chamber packed with spirally-wound wires which cause turbulent mixing thereby homogenizing the mixture with minimum band-broadening.

Daughton, C.G.; Sakaji, R.H.

1982-09-08T23:59:59.000Z

215

STIMULATION TECHNOLOGIES FOR DEEP WELL COMPLETIONS  

SciTech Connect (OSTI)

The Department of Energy (DOE) is sponsoring a Deep Trek Program targeted at improving the economics of drilling and completing deep gas wells. Under the DOE program, Pinnacle Technologies is conducting a project to evaluate the stimulation of deep wells. The objective of the project is to assess U.S. deep well drilling & stimulation activity, review rock mechanics & fracture growth in deep, high pressure/temperature wells and evaluate stimulation technology in several key deep plays. Phase 1 was recently completed and consisted of assessing deep gas well drilling activity (1995-2007) and an industry survey on deep gas well stimulation practices by region. Of the 29,000 oil, gas and dry holes drilled in 2002, about 300 were drilled in the deep well; 25% were dry, 50% were high temperature/high pressure completions and 25% were simply deep completions. South Texas has about 30% of these wells, Oklahoma 20%, Gulf of Mexico Shelf 15% and the Gulf Coast about 15%. The Rockies represent only 2% of deep drilling. Of the 60 operators who drill deep and HTHP wells, the top 20 drill almost 80% of the wells. Six operators drill half the U.S. deep wells. Deep drilling peaked at 425 wells in 1998 and fell to 250 in 1999. Drilling is expected to rise through 2004 after which drilling should cycle down as overall drilling declines.

Stephen Wolhart

2003-06-01T23:59:59.000Z

216

Geohydrology of Pahute Mesa-3 test well, Nye County, Nevada  

SciTech Connect (OSTI)

The Pahute Mesa-3 test well is on Pahute Mesa about 3 miles west of the Nevada Test Site and 20 miles northeast of Oasis Valley near Beatty, Nevada. The well was drilled for the U.S. Department of Energy Radionuclide Migration Program to monitor conditions near the western edge of the Nevada Test Site. The well was drilled with conventional rotary methods and an air-foam drilling fluid to a depth of 3,019 feet. A 10.75-inch diameter steel casing was installed to a depth of 1,473 feet. The test well penetrates thick units of non-welded to partly welded ash-flow and air-fall tuff of Tertiary age with several thin layers of densely welded tuff, rhyolite and basalt flows, and breccia. Geophysical logs indicate that fractures are significant in the Tiva Canyon Tuff of the Paintbrush Group and this was confirmed by high flow in this unit during a borehole-flow survey. The geophysical logs also show that the effective porosity in tuffaceous units ranges from 19 to 38 percent and averages 30 percent, and the total porosity ranges from 33 to 55 percent and averages 42 percent. The measured temperature gradient of 1.00 degree Celsius per 100 feet is steep, but is similar to that of other nearby wells, one of which penetrates a buried granite intrusion. Injection tests for six intervals of the well yielded transmissivities that ranged from 3.1 x 10{sup -3} to 25 feet squared per day and hydraulic conductivities that ranged from 6 x 10{sup -5} to 0.12 foot per day. The sum of the transmissivities is 28 feet squared per day and the geometric mean of hydraulic conductivity is 1.7 x 10{sup -3} foot per day. Estimates of storage coefficient range from 2.1 x 10{sup -5} to 3.8 x 10{sup -3}, indicating that the aquifer responded to the injection tests in a confined manner. An aquifer test produced a drawdown of 78 feet during 31 hours of testing at 169 gallons per minute.

Kilroy, K.C.; Savard, C.S.

1997-02-01T23:59:59.000Z

217

Old Wright Well Greenhouse Low Temperature Geothermal Facility | Open  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy ResourcesLoading map...(UtilityCounty, Michigan: Energy ResourcesCoMaine: Energy Resources Jump to:Energy

218

Lithologic Descriptions and Temperature Profiles of Five Wells in the  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy Resources Jump to:46 - 429Lacey,(Monaster And Coolbaugh, 2007)is

219

Countryman Well Greenhouse Low Temperature Geothermal Facility | Open  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address: 160Benin:EnergyWisconsin:2003) |Cordova Electric633211°,of Forest HealthClub,Energy

220

Buckhorn Mineral Wells Pool & Spa Low Temperature Geothermal Facility |  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address: 160Benin: EnergyBoston Areais a village inBrownfieldBrussels,Buchtel, Ohio:SiliconOpen

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Buckhorn Mineral Wells Space Heating Low Temperature Geothermal Facility |  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address: 160Benin: EnergyBoston Areais a village inBrownfieldBrussels,Buchtel,

222

Pagosa Springs Private Wells Space Heating Low Temperature Geothermal  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy ResourcesLoading map...(UtilityCounty,Orleans County,PPP EquipmentPartners LLC5 ClimateFacility | Open

223

Jackson Well Springs Space Heating Low Temperature Geothermal Facility |  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy Resources Jump to:46 - 429 Throttled (botOpen Energy2005) |JMalucelliIowa Andrew,Jackson

224

High Temperature Quantum Well Materials | Department of Energy  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-UpHeatMulti-Dimensional Subject:Ground Hawaii HIGH PERFORMANCE andHigh Risk PlanD2

225

Temperature Data From Wells in Long Valley Caldera, California | Open  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia:FAQ < RAPID Jump to:Seadov Pty LtdSteen,Ltd Jump to:Taos County,Tees Valley(Newman,Telluric

226

Estimation of static formation temperatures in geothermal wells | Open  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address:011-DNA Jump37. It isInformationexplains a4 Climate Zone Subtype A.EssexApproachEnergy

227

High Temperature, High Pressure Devices for Zonal Isolation in...  

Broader source: Energy.gov (indexed) [DOE]

High Temperature, High Pressure Devices for Zonal Isolation in Geothermal Wells High Temperature, High Pressure Devices for Zonal Isolation in Geothermal Wells High Temperature,...

228

Universal Microfluidic Gradient Generator Daniel Irimia1  

E-Print Network [OSTI]

Universal Microfluidic Gradient Generator Daniel Irimia1 , Dan A Geba2 , Mehmet Toner1 1 Bio, Building 114, 16th St, Charlestown, MA 02129. Email: mtoner@hms.harvard.edu Keywords: microfluidics cells in vitro. While microfluidic devices have shown unmatched capability in generating linear stable

Geba, Dan-Andrei

229

Fourier Accelerated Conjugate Gradient Lattice Gauge Fixing  

E-Print Network [OSTI]

We provide details of the first implementation of a non-linear conjugate gradient method for Landau and Coulomb gauge fixing with Fourier acceleration. We find clear improvement over the Fourier accelerated steepest descent method, with the average time taken for the algorithm to converge to a fixed, high accuracy, being reduced by a factor of 2 to 4.

R. J. Hudspith

2014-05-22T23:59:59.000Z

230

Joining of Tungsten Armor Using Functional Gradients  

SciTech Connect (OSTI)

The joining of low thermal expansion armor materials such as tungsten to high thermal expansion heat sink materials has been a major problem in plasma facing component (PFC) development. Conventional planar bonding techniques have been unable to withstand the high thermal induced stresses resulting from fabrication and high heat flux testing. During this investigation, innovative functional gradient joints produced using vacuum plasma spray forming techniques have been developed for joining tungsten armor to copper alloy heat sinks. A model was developed to select the optimum gradient architecture. Based on the modeling effort, a 2mm copper rich gradient was selected. Vacuum plasma pray parameters and procedures were then developed to produce the functional gradient joint. Using these techniques, dual cooling channel, medium scale mockups (32mm wide x 400mm length) were produced with vacuum plasma spray formed tungsten armor. The thickness of the tungsten armor was up to 5mm thick. No evidence of debonding at the interface between the heat sink and the vacuum plasma sprayed material was observed.

John Scott O'Dell

2006-12-31T23:59:59.000Z

231

Photopolymerization in Microfluidic Gradient Generators: Microscale  

E-Print Network [OSTI]

-compliance profiles that are tunable on the micro- scale. The most straightforward way to create substrates with vari through the development of microfluidic networks,[7,8] with which one can easily generate solution (e microscale gradients with microfluidic networks, and a recent study that demon- strated

232

Gradient zone-boundary control in salt-gradient solar ponds  

DOE Patents [OSTI]

A method and apparatus for suppressing zone boundary migration in a salt gradient solar pond includes extending perforated membranes across the pond at the boundaries, between the convective and non-convective zones, the perforations being small enough in size to prevent individual turbulence disturbances from penetrating the hole, but being large enough to allow easy molecular diffusion of salt thereby preventing the formation of convective zones in the gradient layer. The total area of the perforations is a sizeable fraction of the membrane area to allow sufficient salt diffusion while preventing turbulent entrainment into the gradient zone.

Hull, J.R.

1982-09-29T23:59:59.000Z

233

Flow in geothermal wells: Part III. Calculation model for self-flowing well  

SciTech Connect (OSTI)

The theoretical model described predicts the temperature, pressure, dynamic dryness fraction, and void fraction along the vertical channel of two-phase flow. The existing data from operating wells indicate good agreement with the model. (MHR)

Bilicki, Z.; Kestin, J.; Michaelides, E.E.

1981-06-01T23:59:59.000Z

234

Stimulation Technologies for Deep Well Completions  

SciTech Connect (OSTI)

The Department of Energy (DOE) is sponsoring the Deep Trek Program targeted at improving the economics of drilling and completing deep gas wells. Under the DOE program, Pinnacle Technologies conducted a study to evaluate the stimulation of deep wells. The objective of the project was to review U.S. deep well drilling and stimulation activity, review rock mechanics and fracture growth in deep, high-pressure/temperature wells and evaluate stimulation technology in several key deep plays. This report documents results from this project.

Stephen Wolhart

2005-06-30T23:59:59.000Z

235

Development Wells At Salt Wells Area (Nevada Bureau of Mines...  

Open Energy Info (EERE)

Salt Wells Area (Nevada Bureau of Mines and Geology, 2009) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Development Wells At Salt Wells Area...

236

A Resource Assessment Of Geothermal Energy Resources For Converting Deep Gas Wells In Carbonate Strata Into Geothermal Extraction Wells: A Permian Basin Evaluation  

SciTech Connect (OSTI)

Previously conducted preliminary investigations within the deep Delaware and Val Verde sub-basins of the Permian Basin complex documented bottom hole temperatures from oil and gas wells that reach the 120-180C temperature range, and occasionally beyond. With large abundances of subsurface brine water, and known porosity and permeability, the deep carbonate strata of the region possess a good potential for future geothermal power development. This work was designed as a 3-year project to investigate a new, undeveloped geographic region for establishing geothermal energy production focused on electric power generation. Identifying optimum geologic and geographic sites for converting depleted deep gas wells and fields within a carbonate environment into geothermal energy extraction wells was part of the project goals. The importance of this work was to affect the three factors limiting the expansion of geothermal development: distribution, field size and accompanying resource availability, and cost. Historically, power production from geothermal energy has been relegated to shallow heat plumes near active volcanic or geyser activity, or in areas where volcanic rocks still retain heat from their formation. Thus geothermal development is spatially variable and site specific. Additionally, existing geothermal fields are only a few 10’s of square km in size, controlled by the extent of the heat plume and the availability of water for heat movement. This plume radiates heat both vertically as well as laterally into the enclosing country rock. Heat withdrawal at too rapid a rate eventually results in a decrease in electrical power generation as the thermal energy is “mined”. The depletion rate of subsurface heat directly controls the lifetime of geothermal energy production. Finally, the cost of developing deep (greater than 4 km) reservoirs of geothermal energy is perceived as being too costly to justify corporate investment. Thus further development opportunities for geothermal resources have been hindered. To increase the effective regional implementation of geothermal resources as an energy source for power production requires meeting several objectives. These include: 1) Expand (oil and gas as well as geothermal) industry awareness of an untapped source of geothermal energy within deep permeable strata of sedimentary basins; 2) Identify and target specific geographic areas within sedimentary basins where deeper heat sources can be developed; 3) Increase future geothermal field size from 10 km2 to many 100’s km2 or greater; and 4) Increase the productive depth range for economic geothermal energy extraction below the current 4 km limit by converting deep depleted and abandoned gas wells and fields into geothermal energy extraction wells. The first year of the proposed 3-year resource assessment covered an eight county region within the Delaware and Val Verde Basins of West Texas. This project has developed databases in Excel spreadsheet form that list over 8,000 temperature-depth recordings. These recordings come from header information listed on electric well logs recordings from various shallow to deep wells that were drilled for oil and gas exploration and production. The temperature-depth data is uncorrected and thus provides the lower temperature that is be expected to be encountered within the formation associated with the temperature-depth recording. Numerous graphs were developed from the data, all of which suggest that a log-normal solution for the thermal gradient is more descriptive of the data than a linear solution. A discussion of these plots and equations are presented within the narrative. Data was acquired that enable the determination of brine salinity versus brine density with the Permian Basin. A discussion on possible limestone and dolostone thermal conductivity parameters is presented with the purpose of assisting in determining heat flow and reservoir heat content for energy extraction. Subsurface maps of temperature either at a constant depth or within a target geothermal reservoir are discusse

Erdlac, Richard J., Jr.

2006-10-12T23:59:59.000Z

237

Low temperature geothermal resource evaluation of the Moses Lake-Ritzville-Connell area, Washington  

SciTech Connect (OSTI)

The study area is located in portions of Adams, Grant, Lincoln, and Franklin counties of eastern Washington. The area is representative of a complex stratigraphic and geohydrologic system within the basalt flows of the Columbia River Basalt Group. Fluid temperature data were collected by three different agencies. The Geological Engineering Section (WSU) at Washington State University, runs a continuous fluid temperature (FT) log as part of a complete suite of geophysical logs. The US Geological Survey (USGS) runs a continuous fluid FT log in conjunction with caliper and natural-gamma logs. Southern Methodist University (SMU) and the Washington State Department of Natural Resources, Division of Geology and Earth Resources (DNR), have cooperated in gathering FT data. The DNR-SMU data were collected by taking temperature measurements at 5 m intervals. Bottom-hole temperatures (BHT) and bottom-hole depths (BHD) of selected wells in the study area are given. A technique developed by Biggane (1982) was used to determine the geothermal gradients within the area. A least squares linear regression analysis of the relationship between the BHT and BHD was used to determine the geothermal gradient of a given well data group (WDG).

Widness, S.

1983-11-01T23:59:59.000Z

238

Top hole drilling with dual gradient technology to control shallow hazards  

E-Print Network [OSTI]

3.2 Riserless Dual Gradient Drilling Technology Description .........................36 3.2.1 Kick Detection.............................................................................37 3.2.2 Well Control ?Modified Driller?s Method... ? PRESSURE @ TOP OF KICK GRAPHS ? SET #1..........................140 ix Page APPENDIX F ? PRESSURE @ TOP OF KICK GRAPHS ? SET #2 ..........................159 VITA...

Elieff, Brandee Anastacia Marie

2006-10-30T23:59:59.000Z

239

Automated apparatus for producing gradient gels  

DOE Patents [OSTI]

Apparatus for producing a gradient gel which serves as a standard medium for a two-dimensional analysis of proteins, the gel having a density gradient along its height formed by a variation in gel composition, with the apparatus including first and second pumping means each including a plurality of pumps on a common shaft and driven by a stepping motor capable of providing small incremental changes in pump outputs for the gel ingredients, the motors being controlled, by digital signals from a digital computer, a hollow form or cassette for receiving the gel composition, means for transferring the gel composition including a filler tube extending near the bottom of the cassette, adjustable horizontal and vertical arms for automatically removing and relocating the filler tube in the next cassette, and a digital computer programmed to automatically control the stepping motors, arm movements, and associated sensing operations involving the filling operation.

Anderson, Norman L. (Clarendon Hills, IL)

1986-01-01T23:59:59.000Z

240

Exploration of very high gradient cavities  

SciTech Connect (OSTI)

Several of the 9-cell ILC cavities processed at Jlab within ongoing ILC R&D program have shown interesting behavior at high fields, such as mode mixing and sudden field emission turn-on during quench. Equipped with thermometry and oscillating superleak transducer (OST) system for quench detection, we couple our RF measurements with local dissipation measurements. In this contribution we report on our findings with high gradient SRF cavities.

Grigory Eremeev

2011-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Fast quantum algorithm for numerical gradient estimation  

E-Print Network [OSTI]

Given a blackbox for f, a smooth real scalar function of d real variables, one wants to estimate the gradient of f at a given point with n bits of precision. On a classical computer this requires a minimum of d+1 blackbox queries, whereas on a quantum computer it requires only one query regardless of d. The number of bits of precision to which f must be evaluated matches the classical requirement in the limit of large n.

Stephen P. Jordan

2005-01-02T23:59:59.000Z

242

Energy Gradient Theory of Hydrodynamic Instability  

E-Print Network [OSTI]

A new universal theory for flow instability and turbulent transition is proposed in this study. Flow instability and turbulence transition have been challenging subjects for fluid dynamics for a century. The critical condition of turbulent transition from theory and experiments differs largely from each other for Poiseuille flows. In this paper, a new mechanism of flow instability and turbulence transition is presented for parallel shear flows and the energy gradient theory of hydrodynamic instability is proposed. It is stated that the total energy gradient in the transverse direction and that in the streamwise direction of the main flow dominate the disturbance amplification or decay. A new dimensionless parameter K for characterizing flow instability is proposed for wall bounded shear flows, which is expressed as the ratio of the energy gradients in the two directions. It is thought that flow instability should first occur at the position of Kmax which may be the most dangerous position. This speculation is confirmed by Nishioka et al's experimental data. Comparison with experimental data for plane Poiseuille flow and pipe Poiseuille flow indicates that the proposed idea is really valid. It is found that the turbulence transition takes place at a critical value of Kmax of about 385 for both plane Poiseuille flow and pipe Poiseuille flow, below which no turbulence will occur regardless the disturbance. More studies show that the theory is also valid for plane Couette flows and Taylor-Couette flows between concentric rotating cylinders.

Hua-Shu Dou

2005-01-28T23:59:59.000Z

243

Surface Indicators of Geothermal Activity at Salt Wells, Nevada...  

Open Energy Info (EERE)

structural controls, and potential subsurface reservoir temperatures of geothermal fluids. An example is provided by the Salt Wells geothermal system in Churchill County,...

244

Analytic energy gradients for constrained DFT-configuration interaction  

SciTech Connect (OSTI)

The constrained density functional theory-configuration interaction (CDFT-CI) method has previously been used to calculate ground-state energies and barrier heights, and to describe electronic excited states, in particular conical intersections. However, the method has been limited to evaluating the electronic energy at just a single nuclear configuration, with the gradient of the energy being available only via finite difference. In this paper, we present analytic gradients of the CDFT-CI energy with respect to nuclear coordinates, which gives the potential for accurate geometry optimization and molecular dynamics on both the ground and excited electronic states, a realm which is currently quite challenging for electronic structure theory. We report the performance of CDFT-CI geometry optimization for representative reaction transition states as well as molecules in an excited state. The overall accuracy of CDFT-CI for computing barrier heights is essentially unchanged whether the energies are evaluated at geometries obtained from quadratic configuration-interaction singles and doubles (QCISD) or CDFT-CI, indicating that CDFT-CI produces very good reaction transition states. These results open up tantalizing possibilities for future work on excited states.

Kaduk, Benjamin; Tsuchimochi, Takashi; Van Voorhis, Troy, E-mail: tvan@mit.edu [Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139 (United States)

2014-05-14T23:59:59.000Z

245

Feedback Mechanism for Microtubule Length Regulation by Stathmin Gradients  

E-Print Network [OSTI]

We formulate and analyze a theoretical model for the regulation of microtubule (MT) polymerization dynamics by the signaling proteins Rac1 and stathmin. In cells, the MT growth rate is inhibited by cytosolic stathmin, which, in turn, is inactivated by Rac1. Growing MTs activate Rac1 at the cell edge, which closes a positive feedback loop. We investigate both tubulin sequestering and catastrophe promotion as mechanisms for MT growth inhibition by stathmin. For a homogeneous stathmin concentration in the absence of Rac1, we find a switch-like regulation of the MT mean length by stathmin. For constitutively active Rac1 at the cell edge, stathmin is deactivated locally, which establishes a spatial gradient of active stathmin. In this gradient, we find a stationary bimodal MT length distributions for both mechanisms of MT growth inhibition by stathmin. One subpopulation of the bimodal length distribution can be identified with fast growing and long pioneering MTs in the region near the cell edge, which have been observed experimentally. The feedback loop is closed through Rac1 activation by MTs. For tubulin sequestering by stathmin, this establishes a bistable switch with two stable states: one stable state corresponds to upregulated MT mean length and bimodal MT length distributions, i.e., pioneering MTs; the other stable state corresponds to an interrupted feedback with short MTs. Stochastic effects as well as external perturbations can trigger switching events. For catastrophe promoting stathmin we do not find bistability.

Maria Zeitz; Jan Kierfeld

2014-12-09T23:59:59.000Z

246

A Preconditioner for a Primal-Dual Newton Conjugate Gradients ...  

E-Print Network [OSTI]

Dec 30, 2014 ... A Preconditioner for a Primal-Dual Newton Conjugate Gradients Method for Compressed Sensing Problems.

Kimon Fountoulakis

2014-12-30T23:59:59.000Z

247

Optimization Online - Conjugate gradient methods based on secant ...  

E-Print Network [OSTI]

Sep 28, 2011 ... Conjugate gradient methods based on secant conditions that generate descent search directions for unconstrained optimization.

Y Narushima

2011-09-28T23:59:59.000Z

248

A three-term conjugate gradient method with sufficient descent ...  

E-Print Network [OSTI]

Finally, some numerical results of the proposed method are given. keyword; Unconstrained optimization, three-term conjugate gradient method, sufficient.

2009-11-02T23:59:59.000Z

249

AN EXTENDED CLASS OF NONLINEAR CONJUGATE GRADIENT METHODS \\Lambda  

E-Print Network [OSTI]

AN EXTENDED CLASS OF NONLINEAR CONJUGATE GRADIENT METHODS \\Lambda Y. H. Dai and Y. Yuan State Key 100080, P. R. China. Email: dyh,yyx@lsec.cc.ac.cn Abstract Conjugate gradient methods are very important be analyzed uniformly, conjugate gradient methods are often analyzed individually. Recently, Dai and Yuan

Yuan, Ya-xiang

250

AN AUGMENTED CONJUGATE GRADIENT METHOD FOR SOLVING CONSECUTIVE  

E-Print Network [OSTI]

AN AUGMENTED CONJUGATE GRADIENT METHOD FOR SOLVING CONSECUTIVE SYMMETRIC POSITIVE DEFINITE LINEAR definite matrix A. The conjugate gradient method applied to the first system generates a Krylov subspace conjugate gradient method is then applied with a specific initial guess and initial descent direction

Paris-Sud XI, Université de

251

CONVERGENCE PROPERTIES OF NONLINEAR CONJUGATE GRADIENT METHODS1  

E-Print Network [OSTI]

CONVERGENCE PROPERTIES OF NONLINEAR CONJUGATE GRADIENT METHODS1 Yuhong Dai2 , Jiye Han3 , Guanghui contributions on convergence studies of conjugate gradient methods have been made by Gilbert and Nocedal [6 for ensuring the global convergence of conjugate gradient methods. This paper shows that the sufficient descent

Yuan, Ya-xiang

252

Preconditioned Conjugate Gradient Methods for Three Dimensional Linear Elasticity  

E-Print Network [OSTI]

Preconditioned Conjugate Gradient Methods for Three Dimensional Linear Elasticity by John Kenneth. A brief review is also made of stopping criteria for conjugate gradient solvers. One method based and tested with poor results. iv #12;Contents 1 Introduction 1 1.1 Preconditioned Conjugate Gradient Methods

Waterloo, University of

253

CG DESCENT, A CONJUGATE GRADIENT METHOD WITH GUARANTEED DESCENT  

E-Print Network [OSTI]

CG DESCENT, A CONJUGATE GRADIENT METHOD WITH GUARANTEED DESCENT #3; WILLIAM W. HAGER y AND HONGCHAO are given. Key words. Conjugate gradient method, unconstrained optimization, convergence, line search, Wolfe nonlinear conjugate gradient method for solving an unconstrained optimization problem min ff(x) : x 2

Zhang, Hongchao

254

Exploiting Matrix Symmetry to Improve FPGA-Accelerated Conjugate Gradient  

E-Print Network [OSTI]

the Conjugate Gradient (CG) method using an FPGA co-processor. As in previous approaches, our coExploiting Matrix Symmetry to Improve FPGA- Accelerated Conjugate Gradient Jason D. Bakos, Krishna, high- performance computing, sparse matrix vector multiply, conjugate gradient I. INTRODUCTION Linear

Bakos, Jason D.

255

A conjugate gradient learning algorithm for recurrent neural networks  

E-Print Network [OSTI]

]. In particular, the conjugate gradient method is commonly used in training BP networks due to its speed1 A conjugate gradient learning algorithm for recurrent neural networks (Revised Version) Wing algorithm by incorporating conjugate gradient computation into its learning procedure. The resulting

Mak, Man-Wai

256

Gradient-based Methods for Production Optimization of Oil Reservoirs  

E-Print Network [OSTI]

Gradient-based Methods for Production Optimization of Oil Reservoirs Eka Suwartadi Doctoral Thesis oil reservoirs. Gradient- based optimization, which utilizes adjoint-based gradient computation optimization for water flooding in the secondary phase of oil recovery is the main topic in this thesis

Foss, Bjarne A.

257

Single-Well and Cross-Well Seismic At Salt Wells Area (Bureau...  

Open Energy Info (EERE)

Seismic At Salt Wells Area (Bureau of Land Management, 2009) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Single-Well and Cross-Well Seismic...

258

Recompletion Report for Well UE-10j  

SciTech Connect (OSTI)

Existing Well UE-10j was deepened and recompleted for the U.S. Department of Energy, Nevada Operations Office in support of the Nevada Environmental Restoration Project at the Nevada Test Site, Nye County, Nevada. The well was originally drilled to a total depth of 725.4 meters in 1965 for use as a hydrologic test hole in the northern portion of Yucca Flat in Area 8 of the Nevada Test Site. The well is located up-gradient of the Yucca Flat underground test area and penetrates deep into the Paleozoic rocks that form the lower carbonate aquifer of the NTS and surrounding areas. The original 24.4-centimeter-diameter borehole was drilled to a depth of 725.4 meters and left uncompleted. Water-level measurements were made periodically by the U.S. Geological Survey, but access to the water table was lost between 1979 and 1981 due to hole sloughing. In 1993, the hole was opened to 44.5 centimeters and cased off to a depth of 670.0 meters. The hole diameter was then decreased to 31.1 centimeters for drilling to a total depth of 796.4 meters. The depth to water in the open borehole was measured at 658.7 meters on March 18, 1993.

M. J. Townsend

2000-05-01T23:59:59.000Z

259

The effect of density gradient on the growth rate of relativistic Weibel instability  

SciTech Connect (OSTI)

In this paper, the effect of density gradient on the Weibel instability growth rate is investigated. The density perturbations in the near corona fuel, where temperature anisotropy, ?, is larger than the critical temperature anisotropy, ?{sub c}, (??>??{sub c}), enhances the growth rate of Weibel instability due to the sidebands coupled with the electron oscillatory velocity. But for ???2. The analysis shows that relativistic effects and density gradient tend to stabilize the Weibel instability. The growth rate can be reduced by 88% by reducing ? by a factor of 100 and increasing relativistic parameter by a factor of 3.

Mahdavi, M., E-mail: m.mahdavi@umz.ac.ir [Physics Department, University of Mazandaran, P.O. Box 47415-416, Babolsar (Iran, Islamic Republic of); Khodadadi Azadboni, F., E-mail: f.khodadadi@stu.umz.ac.ir [Physics Department, University of Mazandaran, P.O. Box 47415-416, Babolsar (Iran, Islamic Republic of); Young Researchers Club, Sari Branch, Islamic Azad University, P.O. Box 48161-194, Sari (Iran, Islamic Republic of)

2014-02-15T23:59:59.000Z

260

Ducted kinetic Alfven waves in plasma with steep density gradients  

SciTech Connect (OSTI)

Given their high plasma density (n {approx} 10{sup 13} cm{sup -3}), it is theoretically possible to excite Alfven waves in a conventional, moderate length (L {approx} 2 m) helicon plasma source. However, helicon plasmas are decidedly inhomogeneous, having a steep radial density gradient, and typically have a significant background neutral pressure. The inhomogeneity introduces regions of kinetic and inertial Alfven wave propagation. Ion-neutral and electron-neutral collisions alter the Alfven wave dispersion characteristics. Here, we present the measurements of propagating kinetic Alfven waves in helium helicon plasma. The measured wave dispersion is well fit with a kinetic model that includes the effects of ion-neutral damping and that assumes the high density plasma core defines the radial extent of the wave propagation region. The measured wave amplitude versus plasma radius is consistent with the pile up of wave magnetic energy at the boundary between the kinetic and inertial regime regions.

Houshmandyar, Saeid [Solar Observatory Department, Prairie View A and M University, Prairie View, Texas 77446 (United States); Department of Physics, West Virginia University, Morgantown, West Virginia 26506-6315 (United States); Scime, Earl E. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506-6315 (United States)

2011-11-15T23:59:59.000Z

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Strict convexity of the free energy for non-convex gradient models at moderate $?$  

E-Print Network [OSTI]

We consider a gradient interface model on the lattice with interaction potential which is a non-convex perturbation of a convex potential. We show using a one-step multiple scale analysis the strict convexity of the surface tension at high temperature. This is an extension of Funaki and Spohn's result, where the strict convexity of potential was crucial in their proof that for every tilt there is a unique, shift invariant, ergodic Gibbs measure for the $\

Codina Cotar; Jean-Dominique Deuschel; Stefan Müller

2008-01-08T23:59:59.000Z

262

Well-pump alignment system  

DOE Patents [OSTI]

An improved well-pump for geothermal wells, an alignment system for a well-pump, and to a method for aligning a rotor and stator within a well-pump, wherein the well-pump has a whistle assembly formed at a bottom portion thereof, such that variations in the frequency of the whistle, indicating misalignment, may be monitored during pumping.

Drumheller, Douglas S. (Cedar Crest, NM)

1998-01-01T23:59:59.000Z

263

Well Permits (District of Columbia)  

Broader source: Energy.gov [DOE]

Well permits are required for the installation of wells in private and public space. Wells are defined as any trest hole, shaft, or soil excavation created by any means including, but not limited...

264

Dielectric-Lined High-Gradient Accelerator Structure  

SciTech Connect (OSTI)

Rectangular particle accelerator structures with internal planar dielectric elements have been studied, with a view towards devising structures with lower surface fields for a given accelerating field, as compared with structures without dielectrics. Success with this concept is expected to allow operation at higher accelerating gradients than otherwise on account of reduced breakdown probabilities. The project involves studies of RF breakdown on amorphous dielectrics in test cavities that could enable high-gradient structures to be built for a future multi-TeV collider. The aim is to determine what the limits are for RF fields at the surfaces of selected dielectrics, and the resulting acceleration gradient that could be achieved in a working structure. The dielectric of principal interest in this study is artificial CVD diamond, on account of its advertised high breakdown field ({approx}2 GV/m for dc), low loss tangent, and high thermal conductivity. Experimental studies at mm-wavelengths on materials and structures for achieving high acceleration gradient were based on the availability of the 34.3 GHz third-harmonic magnicon amplifier developed by Omega-P, and installed at the Yale University Beam Physics Laboratory. Peak power from the magnicon was measured to be about 20 MW in 0.5 {micro}s pulses, with a gain of 54 dB. Experiments for studying RF high-field effects on CVD diamond samples failed to show any evidence after more than 10{sup 5} RF pulses of RF breakdown up to a tangential surface field strength of 153 MV/m; studies at higher fields were not possible due to a degradation in magnicon performance. A rebuild of the tube is underway at this writing. Computed performance for a dielectric-loaded rectangular accelerator structure (DLA) shows highly competitive properties, as compared with an existing all-metal structure. For example, comparisons were made of a DLA structure having two planar CVD diamond elements with a all-metal CERN structure HDS operating at 30 GHz. It was shown that the ratio of maximum surface electric field to accelerating field at the metal wall is only 0.35-0.4 for DLA, much smaller than the value 2.2 for HDS; and the ratio of surface magnetic field to accelerating field is 3.0 mA/V for DLA, compared with 3.45 mA/V for HDS. These values bode well for DLA in helping to avoid breakdown and to reducing pulsed surface heating and fatigue. The shunt impedance is found to be 160-175 M{Omega}/m for DLA, as compared to 99 M{Omega}/m for HDS. Conclusions are reached from this project that CVD diamond appears promising as a dielectric with a high threshold for RF breakdown, and that rectangular accelerator structures can be devised using planar CVD diamond elements that could be operated at higher acceleration gradients with low probability of RF breakdown, as compared with corresponding all-metallic structures.

Jay L. Hirshfield

2012-04-24T23:59:59.000Z

265

Preparation and characterization of gradient polymer films  

SciTech Connect (OSTI)

Gradient polymers are multicomponent polymers whose chemical constitution varies with depth in the sample. Although these polymers may possess unique mechanical, optical, and barrier properties they remain relatively unexplored. This work is a study of the preparation of gradient polymers by sequential exposure of films to a diffusing monomer followed by electron beam irradiation. Initial experiments involved immersion of poly(vinyl chloride) (PVC) films in styrene or n-butyl methacrylate (BMA) for various time periods followed by irradiation with 1 or 10 megarads of accelerated electrons. A significant amount of poly(n-butyl methacrylate) (PBMA) formed in PVC/BMA systems, but little polystyrene could be found in the PVC/styrene films. A second set of experiments involved immersion of PVC and polyethylene (PE) films in BMA for 20, 40, 60, and 720 minutes followed by irradiation with 10 megarads of electrons. These films were then characterized using optical microscopy, quantitative transmission Fourier transform infrared spectroscopy (FTIR), and a depth profiling procedure based on quantitative attenuated total reflection (ATR) FTIR. It was concluded that the mechanism of PBMA formation in the polyethylene films was a result of events immediately following irradiation. Atmospheric oxygen diffusing into irradiated films trapped free radicals at the film surfaces. This was followed by storage in an evacuated desiccator where unintentional exposure to BMA vapor took place. This BMA reacted with free radicals that remained within the film cores, polymerizing to PBMA.

Smith, S.C.

1987-01-01T23:59:59.000Z

266

Analysis of Bacterial Communities in Seagrass Bed Sediments by Double-Gradient Denaturing Gradient Gel Electrophoresis  

E-Print Network [OSTI]

Microbial Ecology Analysis of Bacterial Communities in Seagrass Bed Sediments by Double, including the presence or absence of vegetation, depth into sediment, and season. Double- gradient of these similarity coefficients were used to group banding patterns by depth into sediment, presence or absence

Sherman, Tim

267

Thermal lens elimination by gradient-reduced zone coupling of optical beams  

DOE Patents [OSTI]

A thermal gradient-reduced-zone laser includes a laser medium and an optically transparent plate with an index of refraction that is less than the index of refraction of the laser medium. The pump face of the laser medium is bonded to a surface of the optically transparent member. Pump light is directed through the transparent plate to optically pump the solid state laser medium. Heat conduction is mainly through the surface of the laser medium where the heat is introduced by the pump light. Heat flows in a direction opposite to that of the pump light because the side of the laser medium that is opposite to that of the pump face is not in thermal contact with a conductor and thus there is no heat flux (and hence, no temperature gradient), thus producing a thermal gradient-reduced zone. A laser cavity is formed around the laser medium such that laser light oscillating within the laser cavity reflects by total-internal-reflection from the interface between the pump face and the optically transparent plate and enters and exits through a thermal gradient-reduced zone.

Page, Ralph H. (San Ramon, CA); Beach, Raymond J. (Livermore, CA)

2000-01-01T23:59:59.000Z

268

Improving DWF Simulations: the Force Gradient Integrator and the Möbius Accelerated DWF Solver  

E-Print Network [OSTI]

We have implemented a variant of the force gradient integrator proposed by Kennedy et.al. and are using it in our production 2+1 flavor DWF simulations with pion masses of 180 MeV in (4.5fm)3 volumes. We find modest speed-ups (\\sim 20%) from using the force gradient integrator, compared to our previously used Omelyan integrator. On other ensembles, primarily finite temperature 2+1 flavor DWF QCD, we have extensively tuned the Hasenbusch preconditioning masses and achieved speed-ups of 2-3x. Here we have also switched to the force gradient integrator, but this change has not had any impact on the speed. We also report on an improved solver for DWF, which uses M\\"obius fermions, with a smaller fifth dimension than the original DWF fermions, as an intermediate step in the generation of solutions of the Dirac equation. This approach cuts the number of effective Dirac applications by approximately a factor of 2 when the conjugate gradient iteration count is large.

Hantao Yin; Robert D. Mawhinney

2011-11-21T23:59:59.000Z

269

Manufacture of gradient micro-structures of magnesium alloys using two stage extrusion dies  

SciTech Connect (OSTI)

This paper aims to manufacture magnesium alloy metals with gradient micro-structures using hot extrusion process. The extrusion die was designed to have a straight channel part combined with a conical part. Materials pushed through this specially-designed die generate a non-uniform velocity distribution at cross sections inside the die and result in different strain and strain rate distributions. Accordingly, a gradient microstructure product can be obtained. Using the finite element analysis, the forming temperature, effective strain, and effective strain rate distributions at the die exit were firstly discussed for various inclination angles in the conical die. Then, hot extrusion experiments with a two stage die were conducted to obtain magnesium alloy products with gradient micro-structures. The effects of the inclination angle on the grain size distribution at cross sections of the products were also discussed. Using a die of an inclination angle of 15°, gradient micro-structures of the grain size decreasing gradually from 17 ?m at the center to 4 ?m at the edge of product were achieved.

Hwang, Yeong-Maw; Huang, Tze-Hui [Department of Mechanical and Electro-Mechanical Engineering, National Sun Yat-Sen University, No. 70, Lien-Hai Rd., Kaohsiung, 804, Taiwan (China); Alexandrov, Sergei [Institute for Problems in Mechanics, Russian Academy of Sciences, Moscow (Russian Federation); Naimark, Oleg Borisovich [Institute of Continuous Media Mechanics, Russian Academy of Sciences, Perm (Russian Federation); Jeng, Yeau-Ren [Department of Mechanical Engineering and Advanced Institute of Manufacturing with High-tech Innovations, National Chung Cheng University, Ming-Hsiung, Chia-Yi 621, Taiwan (China)

2013-12-16T23:59:59.000Z

270

Well-pump alignment system  

DOE Patents [OSTI]

An improved well-pump for geothermal wells, an alignment system for a well-pump, and to a method for aligning a rotor and stator within a well-pump are disclosed, wherein the well-pump has a whistle assembly formed at a bottom portion thereof, such that variations in the frequency of the whistle, indicating misalignment, may be monitored during pumping. 6 figs.

Drumheller, D.S.

1998-10-20T23:59:59.000Z

271

Charge Hall effect driven by spin-dependent chemical potential gradients and Onsager relations in mesoscopic systems RID B-8398-2011 RID A-7392-2009  

E-Print Network [OSTI]

We study theoretically the spin-Hall effect as well as its reciprocal phenomenon (a transverse charge current driven by a spin-dependent chemical potential gradient) in electron and hole finite size mesoscopic systems. The Landauer...

Hankiewicz, EM; Li, J.; Jungwirth, T.; Niu, Q.; Shen, SQ; Sinova, Jairo.

2005-01-01T23:59:59.000Z

272

Energy loss rate in disordered quantum well  

SciTech Connect (OSTI)

We report the effect of dynamically screened deformation potential on the electron energy loss rate in disordered semiconductor quantum well. Interaction of confined electrons with bulk acoustic phonons has been considered in the deformation coupling. The study concludes that the dynamically screened deformation potential coupling plays a significant role as it substantially affects the power dependency of electron relaxation on temperature and mean free path.

Tripathi, P.; Ashraf, S. S. Z. [Centre of Excellence in Nanomaterials, Faculty of Engineering and Technology, Aligarh Muslim University, Aligarh-202002 (India); Hasan, S. T. [Physics Department, Faculty of Science, The M.S. University of Baroda, Vadodara-390002 (India); Sharma, A. C. [Physics Department, Sibli National College, Azamgarh-276128 (India)

2014-04-24T23:59:59.000Z

273

Constant field gradient planar coupled cavity structure  

DOE Patents [OSTI]

A cavity structure is disclosed having at least two opposing planar housing members spaced apart to accommodate the passage of a particle beam through the structure between the members. Each of the housing members have a plurality of serially aligned hollows defined therein, and also passages, formed in the members, which interconnect serially adjacent hollows to provide communication between the hollows. The opposing planar housing members are spaced and aligned such that the hollows in one member cooperate with corresponding hollows in the other member to form a plurality of resonant cavities aligned along the particle beam within the cavity structure. To facilitate the obtaining of a constant field gradient within the cavity structure, the passages are configured so as to be incrementally narrower in the direction of travel of the particle beam. In addition, the spacing distance between the opposing housing members is configured to be incrementally smaller in the direction of travel of the beam. 16 figs.

Kang, Y.W.; Kustom, R.L.

1999-07-27T23:59:59.000Z

274

High gradient lens for charged particle beam  

DOE Patents [OSTI]

Methods and devices enable shaping of a charged particle beam. A dynamically adjustable electric lens includes a series of alternating a series of alternating layers of insulators and conductors with a hollow center. The series of alternating layers when stacked together form a high gradient insulator (HGI) tube to allow propagation of the charged particle beam through the hollow center of the HGI tube. A plurality of transmission lines are connected to a plurality of sections of the HGI tube, and one or more voltage sources are provided to supply an adjustable voltage value to each transmission line of the plurality of transmission lines. By changing the voltage values supplied to each section of the HGI tube, any desired electric field can be established across the HGI tube. This way various functionalities including focusing, defocusing, acceleration, deceleration, intensity modulation and others can be effectuated on a time varying basis.

Chen, Yu-Jiuan

2014-04-29T23:59:59.000Z

275

High-gradient compact linear accelerator  

DOE Patents [OSTI]

A high-gradient linear accelerator comprises a solid-state stack in a vacuum of five sets of disc-shaped Blumlein modules each having a center hole through which particles are sequentially accelerated. Each Blumlein module is a sandwich of two outer conductive plates that bracket an inner conductive plate positioned between two dielectric plates with different thicknesses and dielectric constants. A third dielectric core in the shape of a hollow cylinder forms a casing down the series of center holes, and it has a dielectric constant different that the two dielectric plates that sandwich the inner conductive plate. In operation, all the inner conductive plates are charged to the same DC potential relative to the outer conductive plates. Next, all the inner conductive plates are simultaneously shorted to the outer conductive plates at the outer diameters. The signal short will propagate to the inner diameters at two different rates in each Blumlein module. A faster wave propagates quicker to the third dielectric core across the dielectric plates with the closer spacing and lower dielectric constant. When the faster wave reaches the inner extents of the outer and inner conductive plates, it reflects back outward and reverses the field in that segment of the dielectric core. All the field segments in the dielectric core are then in unipolar agreement until the slower wave finally propagates to the third dielectric core across the dielectric plates with the wider spacing and higher dielectric constant. During such unipolar agreement, particles in the core are accelerated with gradients that exceed twenty megavolts per meter.

Carder, Bruce M. (205 Rogue River Hwy., Gold Hill, OR 97525)

1998-01-01T23:59:59.000Z

276

High-gradient compact linear accelerator  

DOE Patents [OSTI]

A high-gradient linear accelerator comprises a solid-state stack in a vacuum of five sets of disc-shaped Blumlein modules each having a center hole through which particles are sequentially accelerated. Each Blumlein module is a sandwich of two outer conductive plates that bracket an inner conductive plate positioned between two dielectric plates with different thicknesses and dielectric constants. A third dielectric core in the shape of a hollow cylinder forms a casing down the series of center holes, and it has a dielectric constant different that the two dielectric plates that sandwich the inner conductive plate. In operation, all the inner conductive plates are charged to the same DC potential relative to the outer conductive plates. Next, all the inner conductive plates are simultaneously shorted to the outer conductive plates at the outer diameters. The signal short will propagate to the inner diameters at two different rates in each Blumlein module. A faster wave propagates quicker to the third dielectric core across the dielectric plates with the closer spacing and lower dielectric constant. When the faster wave reaches the inner extents of the outer and inner conductive plates, it reflects back outward and reverses the field in that segment of the dielectric core. All the field segments in the dielectric core are then in unipolar agreement until the slower wave finally propagates to the third dielectric core across the dielectric plates with the wider spacing and higher dielectric constant. During such unipolar agreement, particles in the core are accelerated with gradients that exceed twenty megavolts per meter. 10 figs.

Carder, B.M.

1998-05-26T23:59:59.000Z

277

Pressure &Pressure & TemperatureTemperature  

E-Print Network [OSTI]

to measure atmospheric pressure, and thermometer toprobe to measure atmospheric pressure, and thermometer toprobe to measure atmospheric pressure, and thermometer toprobe to measure atmospheric pressure, and thermometer to measure air temperature.measure air temperature.measure air temperature.measure air temperature

California at Santa Cruz, University of

278

A Nonlinear Conjugate Gradient Algorithm with An Optimal Property ...  

E-Print Network [OSTI]

scaled memoryless BFGS method and propose a family of conjugate gradient methods for unconstrained optimization. An improved Wolfe line search is also ...

2011-06-15T23:59:59.000Z

279

Optimization Online - A three-term conjugate gradient method with ...  

E-Print Network [OSTI]

Dec 3, 2009 ... A three-term conjugate gradient method with sufficient descent property for unconstrained optimization. Y Narushima(narusima ***at*** ...

Y Narushima

2009-12-03T23:59:59.000Z

280

Optimization Online - Linearizing the Method of Conjugate Gradients  

E-Print Network [OSTI]

Sep 9, 2012 ... Abstract: The method of conjugate gradients (CG) is widely used for the iterative solution of large sparse systems of equations $Ax=b$, where ...

Serge Gratton

2012-09-09T23:59:59.000Z

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

A Perry Descent Conjugate Gradient Method with Restricted Spectrum  

E-Print Network [OSTI]

Mar 7, 2011 ... Abstract: A new nonlinear conjugate gradient method, based on Perry's idea, is presented. And it is shown that its sufficient descent property is ...

Dongyi Liu

2011-03-07T23:59:59.000Z

282

Concentration Gradient and Information Energy for Decentralized UAV Control1  

E-Print Network [OSTI]

spills, industrial release accidents, or chemical/biological/nuclear terrorist attacks. DependingConcentration Gradient and Information Energy for Decentralized UAV Control1 William J. Pisano2

Mohseni, Kamran

283

Thermal Gradient Holes At Long Valley Caldera Geothermal Area...  

Open Energy Info (EERE)

Geothermal Area (Farrar, Et Al., 2003) Exploration Activity Details Location Long Valley Caldera Geothermal Area Exploration Technique Thermal Gradient Holes Activity Date 1998 -...

284

alpine elevation gradient: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Niche expansion leads to small-scale adaptive divergence along an elevation gradient in a medium of the Environment, University of California, Los Angeles, CA 90095, USA Niche...

285

Spatiotemporal Gradient Modeling with Applications Harrison S. Quick1  

E-Print Network [OSTI]

, and geospatial information storage, analysis, and distribution systems have led to a burgeoning of spatial 2.3 Gradient analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 2.5 Data analysis

Carlin, Bradley P.

286

A Sparsity Preserving Stochastic Gradient Method for Composite ...  

E-Print Network [OSTI]

Apr 23, 2011 ... Abstract: We propose new stochastic gradient algorithms for solving convex composite optimization problems. In each iteration, our algorithms ...

Qihang Lin

2011-04-23T23:59:59.000Z

287

A Sparsity Preserving Stochastic Gradient Method for Composite ...  

E-Print Network [OSTI]

Apr 23, 2011 ... We propose new stochastic gradient algorithms for solving convex composite optimization problems. In each iteration, our algorithms utilize a ...

2011-04-23T23:59:59.000Z

288

Thermal Gradient Holes At Long Valley Caldera Geothermal Area...  

Open Energy Info (EERE)

Gradient Holes At Long Valley Caldera Geothermal Area (Conservation, 2009) Exploration Activity Details Location Long Valley Caldera Geothermal Area Exploration Technique Thermal...

289

second-order convex splitting schemes for gradient flows with ...  

E-Print Network [OSTI]

Abstract. We construct unconditionally stable, unconditionally uniquely solvable, and second-order accurate (in time) schemes for gradient flows with energy of ...

2011-11-08T23:59:59.000Z

290

Existence and uniqueness of global classical solutions of a gradient ...  

E-Print Network [OSTI]

This gradient flow is generated by the Laudau-de Gennes energy functional that ... feature of this evolution problem is that it is generated by an energy functional ...

2015-01-22T23:59:59.000Z

291

An accelerated proximal gradient algorithm for nuclear norm ...  

E-Print Network [OSTI]

Mar 27, 2009 ... An accelerated proximal gradient algorithm for nuclear norm regularized least squares problems. Kim-Chuan Toh (mattohkc ***at*** nus.edu.sg)

Kim-Chuan Toh

2009-03-27T23:59:59.000Z

292

Gradient methods for convex minimization: better rates under ...  

E-Print Network [OSTI]

Mar 20, 2013 ... Gradient methods for convex minimization: better rates under weaker conditions. Hui Zhang(hhuuii.zhang ***at*** gmail.com)

Hui Zhang

2013-03-20T23:59:59.000Z

293

Thermal Gradient Holes At Lake City Hot Springs Area (Warpinski...  

Open Energy Info (EERE)

Warpinski, Et Al., 2004) Exploration Activity Details Location Lake City Hot Springs Area Exploration Technique Thermal Gradient Holes Activity Date Usefulness not indicated...

294

Thermal Gradient Holes At Blue Mountain Geothermal Area (Fairbank...  

Open Energy Info (EERE)

search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Blue Mountain Geothermal Area (Fairbank & Ross, 1999) Exploration Activity Details Location...

295

Thermal Gradient Holes At Blue Mountain Geothermal Area (Fairbank...  

Open Energy Info (EERE)

Blue Mountain Geothermal Area (Fairbank & Niggemann, 2004) Exploration Activity Details Location Blue Mountain Geothermal Area Exploration Technique Thermal Gradient Holes Activity...

296

Thermal Gradient Holes At Long Valley Caldera Geothermal Area...  

Open Energy Info (EERE)

Activity Details Location Long Valley Caldera Geothermal Area Exploration Technique Thermal Gradient Holes Activity Date 1978 - 1985 Usefulness useful DOE-funding Unknown...

297

Thermal Gradient Holes At Waunita Hot Springs Geothermal Area...  

Open Energy Info (EERE)

holes Additional References Retrieved from "http:en.openei.orgwindex.php?titleThermalGradientHolesAtWaunitaHotSpringsGeothermalArea(Zacharakis,1981)&oldid762...

298

Thermal Gradient Holes At Lightning Dock Geothermal Area (Cunniff...  

Open Energy Info (EERE)

Thermal Gradient Holes At Lightning Dock Geothermal Area (Cunniff & Bowers, 2005) Exploration Activity Details Location Lightning Dock Geothermal Area Exploration Technique Thermal...

299

Thermal Gradient Holes At Breitenbush Hot Springs Area (Ingebritsen...  

Open Energy Info (EERE)

Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Breitenbush Hot Springs Area (Ingebritsen, Et Al., 1993)...

300

Thermal Gradient Holes At North Brawley Geothermal Area (Matlick...  

Open Energy Info (EERE)

Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At North Brawley Geothermal Area (Matlick & Jayne, 2008) Exploration...

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Sampling for Bacteria in Wells  

E-Print Network [OSTI]

This publication will instruct you on the proper procedures for collecting a sample from a water well for bacteriological analysis....

Lesikar, Bruce J.

2001-11-15T23:59:59.000Z

302

Radial convection of finite ion temperature, high amplitude plasma blobs  

SciTech Connect (OSTI)

We present results from simulations of seeded blob convection in the scrape-off-layer of magnetically confined fusion plasmas. We consistently incorporate high fluctuation amplitude levels and finite Larmor radius (FLR) effects using a fully nonlinear global gyrofluid model. This is in line with conditions found in tokamak scrape-off-layers (SOL) regions. Varying the ion temperature, the initial blob width, and the initial amplitude, we found an FLR dominated regime where the blob behavior is significantly different from what is predicted by cold-ion models. The transition to this regime is very well described by the ratio of the ion gyroradius to the characteristic gradient scale length of the blob. We compare the global gyrofluid model with a partly linearized local model. For low ion temperatures, we find that simulations of the global model show more coherent blobs with an increased cross-field transport compared to blobs simulated with the local model. The maximal blob amplitude is significantly higher in the global simulations than in the local ones. When the ion temperature is comparable to the electron temperature, global blob simulations show a reduced blob coherence and a decreased cross-field transport in comparison with local blob simulations.

Wiesenberger, M., E-mail: Matthias.Wiesenberger@uibk.ac.at; Kendl, A. [Institute for Ion Physics and Applied Physics, Association EURATOM-ÖAW, University of Innsbruck, A-6020 Innsbruck (Austria); Madsen, J. [Association EURATOM-DTU, Department of Physics, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark)

2014-09-15T23:59:59.000Z

303

High Temperature, High Pressure Devices for Zonal Isolation in...  

Broader source: Energy.gov (indexed) [DOE]

Temperature, High Pressure Devices for Zonal Isolation in Geothermal Wells High Temperature, High Pressure Devices for Zonal Isolation in Geothermal Wells DOE Geothermal Peer...

304

Exploration geothermal gradient drilling, Platanares, Honduras, Central America  

SciTech Connect (OSTI)

This paper is a review and summary of the core drilling operations component of the Honduras Geothermal Resource Development Project at the Platanares geothermal prospect in Honduras, Central America. Three intermediate depth (428 to 679 m) coreholes are the first continuously cored geothermal exploration boreholes in Honduras. These coring operations are part of the Central America Energy Resource Project (CAERP) effort funded by the Agency for International Development (AID) and implemented by the Los Alamos National Laboratory (Los Alamos) in cooperation with the Empresa Nacional de Energia Electrica (ENEE) and the United States Geological Survey (USGS). This report emphasizes coring operations with reference to the stratigraphy, thermal gradient, and flow test data of the boreholes. The primary objectives of this coring effort were (1) to obtain quantitative information on the temperature distribution as a function of depth, (2) to recover fluids associated with the geothermal reservoir, (3) to recover 75% or better core from the subsurface rock units, and (4) to drill into the subsurface rock as deeply as possible in order to get information on potential reservoir rocks, fracture density, permeabilities, and alteration histories of the rock units beneath the site. The three exploration coreholes drilled to depths of 650, 428 and 679 m, respectively, encountered several hot water entries. Coring operations and associated testing began in mid-October 1986 and were completed at the end of June 1987.

Goff, S.J.; Laughlin, A.W.; Ruefenacht, H.D.; Goff, F.E.; Heiken, G.; Ramos, N.

1988-01-01T23:59:59.000Z

305

Soda Lake Well Lithology Data and Geologic Cross-Sections  

SciTech Connect (OSTI)

Comprehensive catalogue of drill?hole data in spreadsheet, shapefile, and Geosoft database formats. Includes XYZ locations of well heads, year drilled, type of well, operator, total depths, well path data (deviations), lithology logs, and temperature data. Plus, 13 cross?sections in Adobe Illustrator format.

Faulds, James E.

2013-12-31T23:59:59.000Z

306

Full-waveform inversion in the time domain with an energy-weighted gradient  

SciTech Connect (OSTI)

When applying full-waveform inversion to surface seismic reflection data, one difficulty is that the deep region of the model is usually not reconstructed as well as the shallow region. We develop an energy-weighted gradient method for the time-domain full-waveform inversion to accelerate the convergence rate and improve reconstruction of the entire model without increasing the computational cost. Three different methods can alleviate the problem of poor reconstruction in the deep region of the model: the layer stripping, depth-weighting and pseudo-Hessian schemes. The first two approaches need to subjectively choose stripping depths and weighting functions. The third one scales the gradient with only the forward propagation wavefields from sources. However, the Hessian depends on wavefields from both sources and receivers. Our new energy-weighted method makes use of the energies of both forward and backward propagated wavefields from sources and receivers as weights to compute the gradient. We compare the reconstruction of our new method with those of the conjugate gradient and pseudo-Hessian methods, and demonstrate that our new method significantly improves the reconstruction of both the shallow and deep regions of the model.

Zhang, Zhigang [Los Alamos National Laboratory; Huang, Lianjie [Los Alamos National Laboratory; Lin, Youzuo [Los Alamos National Laboratory

2011-01-01T23:59:59.000Z

307

Measurement of laser heating in spin exchange optical pumping by NMR diffusion sensitization gradients  

SciTech Connect (OSTI)

This paper details pulsed gradient NMR measurements of the {sup 3}He diffusion coefficient in sealed cells during spin exchange optical pumping. The potential of ultra low field magnetic resonance imgaing (MRI) and NMR for noninvasive measurement of cell pressure is demonstrated. Diffusion sensitization gradients allow measurement of the {sup 3}He diffusion coefficient from which the pressure and/or temperature of the gas can be determined during optical pumping. The pressure measurements were compared with neutron time of flight transmission measurements. Good agreement was observed between the temperature/pressure measurements and predictions based on Chapman-Enskog theory. The technique had sufficient sensitivity to observe the diffusion coefficient increasing with temperature in a sealed cell. With this method, evidence for laser heating of the {sup 3}He during optical pumping was found. The results show that NMR diffusion measurements allow noninvasive measurement of the cell temperature and/or pressure in an optical pumping setup. The method can be expanded using MRI to probe the spatial distribution of the diffusion coefficient. These techniques can be applied to the further investigation of polarization limiting effects such as laser heating.

Parnell, Steven R.; Deppe, Martin H.; Ajraoui, Salma; Parra-Robles, Juan; Wild, Jim M. [Unit of Academic Radiology, University of Sheffield, Royal Hallamshire Hospital, Glossop Road, Sheffield, S10 2JF (United Kingdom); Boag, Stephen [ISIS, Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire, OX11 0QX (United Kingdom)

2010-05-15T23:59:59.000Z

308

Combining Conjugate Direction Methods with Stochastic Approximation of Gradients  

E-Print Network [OSTI]

Combining Conjugate Direction Methods with Stochastic Approximation of Gradients #3; Nicol N-8092 Zurich, Switzerland http://www.icos.ethz.ch/ Abstract The method of conjugate directions provides from conjugate gra- dient in the stochastic (online) setting, us- ing fast Hessian-gradient products

Schraudolph, Nicol N.

309

Combining Conjugate Direction Methods with Stochastic Approximation of Gradients  

E-Print Network [OSTI]

Combining Conjugate Direction Methods with Stochastic Approximation of Gradients Nicol N-8092 Z¨urich, Switzerland http://www.icos.ethz.ch/ Abstract The method of conjugate directions provides conjugate gra- dient in the stochastic (online) setting, us- ing fast Hessian-gradient products to set up

Schraudolph, Nicol N.

310

Evaluation of liquid lift approach to dual gradient  

E-Print Network [OSTI]

the mudline to the rig floor so as to maintain the bottom hole pressure. Several methods have been developed to achieve the dual gradient drilling principle. For this research project, we paid more attention to the liquid lift, dual gradient drilling (riser...

Okafor, Ugochukwu Nnamdi

2009-05-15T23:59:59.000Z

311

Evaluation of liquid lift approach to dual gradient drilling  

E-Print Network [OSTI]

the mudline to the rig floor so as to maintain the bottom hole pressure. Several methods have been developed to achieve the dual gradient drilling principle. For this research project, we paid more attention to the liquid lift, dual gradient drilling (riser...

Okafor, Ugochukwu Nnamdi

2008-10-10T23:59:59.000Z

312

SampleRank: Training Factor Graphs with Atomic Gradients  

E-Print Network [OSTI]

a user-provided loss function to distribute stochastic gradients across an MCMC chain. As a result, parameter updates can be computed between arbitrary MCMC states. Sam- pleRank is not only faster than CD- expensive gradients between the ground-truth and samples along an MCMC chain yielding a stochastic

McCallum, Andrew

313

Well Monitoring System for EGS  

Broader source: Energy.gov [DOE]

EGS well monitoring tools offer a unique set of solutions which will lower costs and increase confidence in future geothermal projects.

314

Well Monitoring System for EGS  

Broader source: Energy.gov (indexed) [DOE]

Peer Review Well Monitoring Systems for EGS Principal Investigator Randy Normann Perma Works LLC May 19, 2010 This presentation does not contain any proprietary confidential, or...

315

Low Temperature Geothermal Resource Evaluation of the Moses Lake-Ritzville-Connell Area, Washington  

SciTech Connect (OSTI)

The study area is located in portions of Adams, Grant, Lincoln, and Franklin counties of eastern Washington. The area is representative of a complex stratigraphic and geohydrologic system within the basalt flows of the Columbia River Basalt Group. The regional piezometric surface and stratigraphic units dip towards the southwest. Fluid temperature data were collected by three different agencies. The Geological Engineering Section (WSU) at Washington State University, runs a continuous fluid temperature (FT) log as part of a complete suite of geophysical logs. The US Geological Survey (USGS) runs a continuous fluid FT log in conjunction with caliper and natural-gamma logs. Southern Methodist University (SMU) and the Washington State Department of Natural Resources, Division of Geology and Earth Resources (DNR), have cooperated in gathering FT data. The DNR-SMU data were collected by taking temperature measurements at 5 m intervals. Bottom-hole temperatures (BHT) and bottom-hole depths (BHD) of selected wells in the study area are given in table 2. Some of the BHT data in table 2 may vary from those previously reported by WSU. These discrepancies are the result of changes in the calibration method of the FT tool. A technique developed by Giggane (1982) was used to determine the geothermal gradients within the area. A least squares linear regression analysis of the relationship between the BHT and BHD was used to determine the geothermal gradient of a given well data group (WDG). Well data groups were selected on the premises of geographic proximity, position within the regional groundwater flow system, land slope azimuth, and land slope dip. Some data points have been excluded from the linear regression analysis on the basis of factors such as duplicate logging of the same hole, down-hole flow, holes not logged to total depth, and questionable FT tool responses.

Widness, Scott

1983-11-01T23:59:59.000Z

316

Geothermal low-temperature reservoir assessment in Dona Ana County, New Mexico. Final report  

SciTech Connect (OSTI)

Sixty-four shallow temperature gradient holes were drilled on the Mesilla Valley East Mesa (east of Interstate Highways 10 and 25), stretching from US Highway 70 north of Las Cruces to NM Highway 404 adjacent to Anthony, New Mexico. Using these data as part of the site selection process, Chaffee Geothermal, Ltd. of Denver, Colorado, drilled two low-temperature geothermal production wells to the immediate north and south of Tortugas Mountain and encountered a significant low-temperature reservoir, with a temperature of about 150{sup 0}F and flow rates of 750 to 1500 gallons per minute at depths from 650 to 1250 feet. These joint exploration activities resulted in the discovery and confirmation of a 30-square-mile low-temperature geothermal anomaly just a few miles to the east of Las Cruces that has been newly named as the Las Cruces east Mesa Geothermal Field. Elevated temperature and heat flow data suggest that the thermal anomaly is fault controlled and extends southward to the Texas border covering a 100-square-mile area. With the exception of some localized perturbations, the anomaly appears to decrease in temperature from the north to the south. Deeper drilling is required in the southern part of the anomaly to confirm the existence of commercially-exploitable geothermal waters.

Icerman, L.; Lohse, R.L.

1983-04-01T23:59:59.000Z

317

Generalized Hooke's law for isotropic second gradient materials  

E-Print Network [OSTI]

In the spirit of Germain the most general objective stored elastic energy for a second gradient material is deduced using a literature result of Fortun\\'e & Vall\\'ee. Linear isotropic constitutive relations for stress and hyperstress in terms of strain and strain-gradient are then obtained proving that these materials are characterized by seven elastic moduli and generalizing previous studies by Toupin, Mindlin and Sokolowski. Using a suitable decomposition of the strain-gradient, it is found a necessary and sufficient condition, to be verified by the elastic moduli, assuring positive definiteness of the stored elastic energy. The problem of warping in linear torsion of a prismatic second gradient cylinder is formulated, thus obtaining a possible measurement procedure for one of the second gradient elastic moduli.

F. dell'Isola; G. Sciarra; S. Vidoli

2010-08-17T23:59:59.000Z

318

Optimization of fractured well performance of horizontal gas wells  

E-Print Network [OSTI]

In low-permeability gas reservoirs, horizontal wells have been used to increase the reservoir contact area, and hydraulic fracturing has been further extending the contact between wellbores and reservoirs. This thesis presents an approach...

Magalhaes, Fellipe Vieira

2009-06-02T23:59:59.000Z

319

Death Valley Lower Carbonate Aquifer Monitoring Program Wells Down gradient of the Proposed Yucca Mountain Nuclear Waste Repository  

SciTech Connect (OSTI)

Inyo County has participated in oversight activities associated with the Yucca Mountain Nuclear Waste Repository since 1987. The overall goal of these studies are the evaluation of far-field issues related to potential transport, by ground water, or radionuclides into Inyo County, including Death Valley, and the evaluation of a connection between the Lower Carbonate Aquifer (LCA) and the biosphere. Our oversight and completed Cooperative Agreement research, and a number of other investigators research indicate that there is groundwater flow between the alluvial and carbonate aquifers both at Yucca Mountain and in Inyo County. In addition to the potential of radionuclide transport through the LCA, Czarnecki (1997), with the US Geological Survey, research indicate potential radionuclide transport through the shallower Tertiary-age aquifer materials with ultimate discharge into the Franklin Lake Playa in Inyo County. The specific purpose of this Cooperative Agreement drilling program was to acquire geological, subsurface geology, and hydrologic data to: (1) establish the existence of inter-basin flow between the Amargosa Basin and Death Valley Basin; (2) characterize groundwater flow paths in the LCA through Southern Funeral Mountain Range, and (3) Evaluation the hydraulic connection between the Yucca Mountain repository and the major springs in Death Valley through the LCA.

Inyo County

2006-07-26T23:59:59.000Z

320

Natural Conjugate Gradient on Complex Flag Manifolds for Complex Independent Subspace  

E-Print Network [OSTI]

conjugate gradient method yields better convergence compared to the natural gradient geodesic search method is the natural gradient geodesic search method (NGS), and the other is the natural conjugate gradient method (NCG the natural gradient or the Newton's method on complex manifolds, however, the behavior of the conjugate

Plumbley, Mark

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

A conjugate Rosen's gradient projection method with global line search for piecewise linear optimization  

E-Print Network [OSTI]

A conjugate Rosen's gradient projection method with global line search for piecewise linear cutting plane method, simplex method, Rosen's gradient projection, conjugate gradient. 1 Introduction the zig-zagging of the gradient projection, we propose a conjugate gradient version of the face simplex

Beltran-Royo, Cesar

322

Efficient and robust gradient enhanced Kriging emulators.  

SciTech Connect (OSTI)

%E2%80%9CNaive%E2%80%9D or straight-forward Kriging implementations can often perform poorly in practice. The relevant features of the robustly accurate and efficient Kriging and Gradient Enhanced Kriging (GEK) implementations in the DAKOTA software package are detailed herein. The principal contribution is a novel, effective, and efficient approach to handle ill-conditioning of GEK's %E2%80%9Ccorrelation%E2%80%9D matrix, RN%CC%83, based on a pivoted Cholesky factorization of Kriging's (not GEK's) correlation matrix, R, which is a small sub-matrix within GEK's RN%CC%83 matrix. The approach discards sample points/equations that contribute the least %E2%80%9Cnew%E2%80%9D information to RN%CC%83. Since these points contain the least new information, they are the ones which when discarded are both the easiest to predict and provide maximum improvement of RN%CC%83's conditioning. Prior to this work, handling ill-conditioned correlation matrices was a major, perhaps the principal, unsolved challenge necessary for robust and efficient GEK emulators. Numerical results demonstrate that GEK predictions can be significantly more accurate when GEK is allowed to discard points by the presented method. Numerical results also indicate that GEK can be used to break the curse of dimensionality by exploiting inexpensive derivatives (such as those provided by automatic differentiation or adjoint techniques), smoothness in the response being modeled, and adaptive sampling. Development of a suitable adaptive sampling algorithm was beyond the scope of this work; instead adaptive sampling was approximated by omitting the cost of samples discarded by the presented pivoted Cholesky approach.

Dalbey, Keith R.

2013-08-01T23:59:59.000Z

323

Gradient projection anti-windup scheme  

E-Print Network [OSTI]

It is a well-recognized fact that control saturation affects virtually all practical control systems. It leads to controller windup, which degrades/limits the system's closed-loop performance, and may cause catastrophic ...

Teo, Chun Sang Justin

2011-01-01T23:59:59.000Z

324

Quantum well multijunction photovoltaic cell  

DOE Patents [OSTI]

A monolithic, quantum well, multilayer photovoltaic cell comprises a p-n junction comprising a p-region on one side and an n-region on the other side, each of which regions comprises a series of at least three semiconductor layers, all p-type in the p-region and all n-type in the n-region; each of said series of layers comprising alternating barrier and quantum well layers, each barrier layer comprising a semiconductor material having a first bandgap and each quantum well layer comprising a semiconductor material having a second bandgap when in bulk thickness which is narrower than said first bandgap, the barrier layers sandwiching each quantum well layer and each quantum well layer being sufficiently thin that the width of its bandgap is between said first and second bandgaps, such that radiation incident on said cell and above an energy determined by the bandgap of the quantum well layers will be absorbed and will produce an electrical potential across said junction.

Chaffin, R.J.; Osbourn, G.C.

1983-07-08T23:59:59.000Z

325

Effect of Gas Turbine Exhaust Temperature, Stack Temperature and Ambient Temperature on Overall Efficiency of Combine Cycle Power Plant  

E-Print Network [OSTI]

Abstract—The gas turbine exhaust temperature, stack temperature and ambient temperature play a very important role during the predication of the performance of combine cycle power plant. This paper covers parametric analysis of effects of gas turbine exhaust temperature, stack temperature and ambient temperature on the overall efficiency of combine cycle power plant keeping the gas turbine efficiency as well as steam turbine efficiency constant. The results shows that out of three variables i.e. turbine exhaust temperature, stack temperature and ambient temperature, the most dominating factor of increasing the overall efficiency of the combine cycle power plant is the stack temperature.

unknown authors

326

Imaging diffusion with non-uniform B{sub 1} gradients.  

SciTech Connect (OSTI)

Rotating-frame imaging with the mathematically well-defined, non-constant magnetic field gradient of toroid cavity detectors represents a new technique to evaluate diffusion in solids, fluids or mixed-phase systems. While conventional NMR methods to measure diffusion utilize constant magnetic field gradients and, therefore, constant k-space wave numbers across the sample volume, the hyperbolic B{sub 1} fields of toroid cavity detectors exhibit large ranges of wave numbers radially distributed around the central conductor. As a consequence, signal amplitudes decay depending on the radial distance from the center axis of the torus. Applying a numerical finite-difference procedure to solve partial differential transport equations makes it possible not only to determine diffusion in toroid detectors to a high precision but also to include and accurately reproduce transport phenomena at or through singularities, such as phase transitions, membranes or impermeable boundaries.

Woelk, K.

1998-01-30T23:59:59.000Z

327

Algorithm PREQN: Fortran 77 Subroutines for Preconditioning the Conjugate Gradient Method  

E-Print Network [OSTI]

Algorithm PREQN: Fortran 77 Subroutines for Preconditioning the Conjugate Gradient Method Jos subroutines for automatically generating pre­ conditioners for the conjugate gradient method. It is designed. Additional Key Words and Phrases: Preconditioning, conjugate gradient method, quasi­ Newton method, Hessian

Nocedal, Jorge

328

COMPARISON OF THE DEFLATED PRECONDITIONED CONJUGATE GRADIENT METHOD AND ALGEBRAIC MULTIGRID FOR COMPOSITE  

E-Print Network [OSTI]

COMPARISON OF THE DEFLATED PRECONDITIONED CONJUGATE GRADIENT METHOD AND ALGEBRAIC MULTIGRID algorithms such as the Preconditioned Conjugate Gradient (PCG) method. This paper considers the Deflated Preconditioned Conjugate Gradient (DPCG) method in which the rigid body modes of sets of elements

MacLachlan, Scott

329

Optimization Online - A conjugate-gradient based approach for ...  

E-Print Network [OSTI]

Feb 29, 2008 ... In particular, it is noted that with a bound on the two-norm of the columns, the method is equivalent to the conjugate-gradient method. Further ...

Fredrik Carlsson

2008-02-29T23:59:59.000Z

330

Potential use of hollow spheres in dual gradient drilling  

E-Print Network [OSTI]

The increasing number of significant deepwater discoveries has pushed the operator and service oil companies to focus their efforts on developing new technologies to drill in deeper water. Dual gradient drilling (DGD) will allow reaching deeper...

Vera Vera, Liliana

2002-01-01T23:59:59.000Z

331

Function of the anterior gradient protein family in cancer   

E-Print Network [OSTI]

Proteomic technologies verified Anterior Gradient 2, AGR-2, as a protein over-expressed in human cancers, including breast, prostate and oesophagus cancers, with the ability to inhibit the tumour suppressor protein p53. AGR-2 gene is a hormone...

Fourtouna, Argyro

2009-01-01T23:59:59.000Z

332

Microsoft PowerPoint - High Gradient Inverse Free Electron Laser...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Hi h G di t Hi h i High Gradient High energy gain Inverse Free Electron Laser at BNL P. Musumeci UCLA Department of Physics and Astronomy ATF user meeting April 2-3 2009 Outline...

333

alternating gradient synchrotron: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

sources also have the advantage of a time structure with a high peak neutron flux. The basic requirement is for a... Bryant, P J 1995-01-01 36 Gradient House. Open...

334

CONSERVATION ECOLOGY -ORIGINAL RESEARCH Conservation through connectivity: can isotopic gradients  

E-Print Network [OSTI]

CONSERVATION ECOLOGY - ORIGINAL RESEARCH Conservation through connectivity: can isotopic gradients Abstract Conservation of migratory wildlife requires knowledge of migratory connectivity between breeding conservation efforts for endangered migratory species (Webster et al. 2002; Rubenstein and Hobson 2004; Webster

Richner, Heinz

335

A parametric study of thermomechanical behavior of functionally gradient materials  

E-Print Network [OSTI]

(FSDT) that accounts for the transverse shear strains and the rotations, coupled with a three dimensional heat conduction equation is formulated for a functionally gradient plate. Both problems are studied by varying the volume fraction of a ceramic...

Chin, Che-Doong

1996-01-01T23:59:59.000Z

336

Computational Inversion of Electron Tomography Images -Gradient Flows  

E-Print Network [OSTI]

Computational Inversion of Electron Tomography Images Using L2 -Gradient Flows Guoliang Xu 1) Ming Computing Institute of Computational Mathematics, Academy of Mathematics and System Sciences, Chinese Academy of Sciences, Beijing 100190, China 2) Department of Computer Sciences and Institute

Texas at Austin, University of

337

Thermal Gradient Holes At Lightning Dock Geothermal Area (Arnold...  

Open Energy Info (EERE)

DOE-funding Unknown Exploration Basis Known shallow hot spot in Animas Valley Notes Four thermal gradient holes were authorized to be drilled by AMEX, but no results were...

338

Generation of Gradients Having Complex Shapes Using Microfluidic Networks  

E-Print Network [OSTI]

Generation of Gradients Having Complex Shapes Using Microfluidic Networks Stephan K. W. Dertinger, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138 This paper describes the generation each carrying different concentrations of substances laminarly and side-by-side generated step

Prentiss, Mara

339

Osteochondral Interface Tissue Engineering using Macroscopic Gradients of Physicochemical Signals  

E-Print Network [OSTI]

of tissue interfaces. Yet, just because tissues are separated from one another by type, function, location, or anatomical prevalence, does not necessarily mean that the interfaces are as easily distinguishable, as the interfaces themselves are highly complex... not yield a “true” continuous gradient, it can have many discrete advantages over continuous gradients. Because of the inherent discontinuous fabrication methods (developing sections separately and fusing together), however, design effort must be placed...

Dormer, Nathan Henry

2011-04-25T23:59:59.000Z

340

Process for cementing geothermal wells  

DOE Patents [OSTI]

A pumpable slurry of coal-filled furfuryl alcohol, furfural, and/or a low molecular weight mono- or copolymer thereof containing, preferably, a catalytic amount of a soluble acid catalyst is used to cement a casing in a geothermal well.

Eilers, Louis H. (Inola, OK)

1985-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

E-Print Network 3.0 - alternating gradient focusing Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

gradient focusing Page: << < 1 2 3 4 5 > >> 1 Gradient Estimation in Global Optimization Algorithms Megan Hazen, Member, IEEE and Maya R. Gupta, Member, IEEE Summary:...

342

E-Print Network 3.0 - advanced gradient based Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Gradients of Poly(N-isopropylacrylamide) Polymer Brushes Prepared by Summary: , an electrochemical-potential-gradient- based method has been developed to generate chemical...

343

Mass Function Gradients and the Need for Dark Matter  

E-Print Network [OSTI]

There is substantial evidence that the initial mass function (IMF) may be a function of the local star formation conditions. In particular, the IMF is predicted to flatten with increasing local luminosity density, with the formation of massive stars being preferentially enhanced in brighter regions. If IMF gradients are general features of galaxies, several previous astrophysical measurements, such as the surface mass densities of spirals (obtained assuming constant mass to light ratios), were plagued by substantial systematic errors. In this Letter, calculations which account for possible IMF gradients are presented of surface densities of spiral galaxies. Compared to previous estimates, the mass densities corrected for IMF gradients are higher in the outer regions of the disks. For a model based on the Milky Way but with an IMF scaled according to R136, the rotation curve without the traditional dark halo component falls with Galactocentric radius, though slower than it would without IMF gradients. For a second model of the Milky Way in which the IMF gradient is increased by 50%, the rotation curve is approximately flat in the outer disk, with a rotational velocity below ~220 km/s only before the traditional dark halo component is added. These results, if generalizable to other galaxies, not only call into question the assertion that dark matter halos are compatible with the flat rotation curves of spiral galaxies, but also may clarify our understanding of a wide variety of other astrophysical phenomena such as the G-dwarf problem, metallicity gradients, and the Tully-Fisher relation.

Jason A. Taylor

1998-03-05T23:59:59.000Z

344

Use of Rapid Temperature Measurements at a 2-Meter Depth to Augment...  

Open Energy Info (EERE)

Measurements at a 2-Meter Depth to Augment Deeper Temperature Gradient Drilling Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Paper: Use of Rapid...

345

Interlocked optimization and fast gradient algorithm for a seismic inverse problem  

SciTech Connect (OSTI)

Highlights: {yields} A 2D extension of the 1D nonlinear inversion of well-seismic data is given. {yields} Appropriate regularization yields a well-determined large scale inverse problem. {yields} An interlocked optimization loop acts as an efficient preconditioner. {yields} The adjoint state method is used to compute the misfit function gradient. {yields} Domain decomposition method yields an efficient parallel implementation. - Abstract: We give a nonlinear inverse method for seismic data recorded in a well from sources at several offsets from the borehole in a 2D acoustic framework. Given the velocity field, approximate values of the impedance are recovered. This is a 2D extension of the 1D inversion of vertical seismic profiles . The inverse problem generates a large scale undetermined ill-conditioned problem. Appropriate regularization terms render the problem well-determined. An interlocked optimization algorithm yields an efficient preconditioning. A gradient algorithm based on the adjoint state method and domain decomposition gives a fast parallel numerical method. For a realistic test case, convergence is attained in an acceptable time with 128 processors.

Metivier, Ludovic, E-mail: ludovic.metivier@gmail.com [LAGA, Universite Paris XIII, 99 Avenue Jean-Baptiste Clement, 93000 Epinay-Villetaneuse (France)

2011-08-10T23:59:59.000Z

346

Method and apparatus for producing a carbon based foam article having a desired thermal-conductivity gradient  

DOE Patents [OSTI]

A carbon based foam article is made by heating the surface of a carbon foam block to a temperature above its graphitizing temperature, which is the temperature sufficient to graphitize the carbon foam. In one embodiment, the surface is heated with infrared pulses until heat is transferred from the surface into the core of the foam article such that the graphitizing temperature penetrates into the core to a desired depth below the surface. The graphitizing temperature is maintained for a time sufficient to substantially entirely graphitize the portion of the foam article from the surface to the desired depth below the surface. Thus, the foam article is an integral monolithic material that has a desired conductivity gradient with a relatively high thermal conductivity in the portion of the core that was graphitized and a relatively low thermal conductivity in the remaining portion of the foam article.

Klett, James W. (Knoxville, TN) [Knoxville, TN; Cameron, Christopher Stan (Sanford, NC) [Sanford, NC

2010-03-02T23:59:59.000Z

347

High Temperature Capacitor Development  

SciTech Connect (OSTI)

The absence of high-temperature electronics is an obstacle to the development of untapped energy resources (deep oil, gas and geothermal). US natural gas consumption is projected to grow from 22 trillion cubic feet per year (tcf) in 1999 to 34 tcf in 2020. Cumulatively this is 607 tcf of consumption by 2020, while recoverable reserves using current technology are 177 tcf. A significant portion of this shortfall may be met by tapping deep gas reservoirs. Tapping these reservoirs represents a significant technical challenge. At these depths, temperatures and pressures are very high and may require penetrating very hard rock. Logistics of supporting 6.1 km (20,000 ft) drill strings and the drilling processes are complex and expensive. At these depths up to 50% of the total drilling cost may be in the last 10% of the well depth. Thus, as wells go deeper it is increasingly important that drillers are able to monitor conditions down-hole such as temperature, pressure, heading, etc. Commercial off-the-shelf electronics are not specified to meet these operating conditions. This is due to problems associated with all aspects of the electronics including the resistors and capacitors. With respect to capacitors, increasing temperature often significantly changes capacitance because of the strong temperature dependence of the dielectric constant. Higher temperatures also affect the equivalent series resistance (ESR). High-temperature capacitors usually have low capacitance values because of these dielectric effects and because packages are kept small to prevent mechanical breakage caused by thermal stresses. Electrolytic capacitors do not operate at temperatures above 150oC due to dielectric breakdown. The development of high-temperature capacitors to be used in a high-pressure high-temperature (HPHT) drilling environment was investigated. These capacitors were based on a previously developed high-voltage hybridized capacitor developed at Giner, Inc. in conjunction with a unique high-temperature electrolyte developed during the course of the program. During this program the feasibility of operating a high voltage hybridized capacitor at 230oC was demonstrated. Capacitor specifications were established in conjunction with potential capacitor users. A method to allow for capacitor operation at both ambient and elevated temperatures was demonstrated. The program was terminated prior to moving into Phase II due to a lack of cost-sharing funds.

John Kosek

2009-06-30T23:59:59.000Z

348

Validation of electron temperature gradient turbulence in the Columbia Linear Machine  

E-Print Network [OSTI]

%, steady-state oscillations at $ 0:3 À 0:5 MHz (in the plasma frame), with azimuthal wave numbers m $ 14À16 cascade of the energy from the fastest growing high-m modes to low-m nonlinear oscillations, which voltage on the inner disk mesh r voltage on the outer ring mesh r1

Lin, Zhihong

349

A Microfluidic Device with a Linear Temperature Gradient for Parallel and Combinatorial Measurements  

E-Print Network [OSTI]

-dimensional grid such as a DNA chip or a multiwell plate. Variables such as buffer conditions, chemical composition on the simple solution to the Fourier heat diffusion equation16 when heat flow is restricted to one direction the direction of heat transfer, and k is the thermal conductivity of the medium in which the heat is flowing

350

Temperature gradient transport growth of potassium tantalate niobate, KTa??xNbxO?, single crystals  

E-Print Network [OSTI]

occurs was not found to vary linearly as reported in references [3, 17) instead the relationship is more parabolic in this region. One reason for this deviation could be the fact that the transition for concentrations x&. 3 are first order but below x... crystallinity, relative dielectric constant and Curie point. Results obtained confirm reported phase diagrams of this system but the relationship between composition and Curie point was found to be a parabolic function instead of a linear relationship...

Goeking, Kent Wayne

1987-01-01T23:59:59.000Z

351

Gravity compensation in dusty-plasmas by application of a temperature gradient  

E-Print Network [OSTI]

Micron sized particles can be suspended or even lifted up in gas by the thermophoretic effect. This has many applications in physics and technology.

Rothermel, H; Morfill, G E; Thomas, H

2001-01-01T23:59:59.000Z

352

Manipulation of Colloids by Nonequilibrium Depletion Force in Temperature Gradient Hong-Ren Jiang1  

E-Print Network [OSTI]

irrespective of their own thermophoretic properties. An amplification of the trapped colloid density's thermophoresis. These results show how to control thermophoretic properties of colloids. PACS numbers: 82.70.Dd

Sano, Masaki

353

Rate of decrease of the specific surface area of dry snow: Isothermal and temperature gradient conditions  

E-Print Network [OSTI]

crystals. These effects drive sublimation/condensation cycles that modify the sizes and shapes of snow through sublimation/condensation and adsorption/desorption cycles. Adsorbed gases can diffuse inside snow variations must be described in models of snow physics and chemistry [Flin et al., 2003; Legagneux and Domine

Domine, Florent

354

Temperature gradients are supported by cantori in chaotic fields S.R. Hudson  

E-Print Network [OSTI]

devil's staircase. [1] T. E. Evans, R. A. Moyer, P. R. Thomas, et al., Phys. Rev. Lett. 92, 235003 (2004

Hudson, Stuart

355

A new well surveying tool  

E-Print Network [OSTI]

directional well was to tip the entire rig, then block up one side of the rotary table so as to incline the uppermost joint of the drill pipe. The accuracy obtained by this method left much to be desired. The technique of controlled directional drilling... by Surveying Device for S and 19 , N and 41 . 21 3. Comparison of Measured Angles and Angles Indicated by Surveying Device for NE snd 9 , W and 45 . . . . . . . ~ 22 ABSTRNl T Ever since the advent of rotary drilling the petroleum industry has been...

Haghighi, Manuchehr Mehdizabeh

1966-01-01T23:59:59.000Z

356

Observation Wells | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentrating Solar Powerstories onFocus AreaDataBusPFAN)Change Assessment Model (GCAM) | OpenWells

357

System for stabbing well casing  

SciTech Connect (OSTI)

Apparatus for stabbing well casing to join casing sections to each other, includes a rotary table assembly for supporting a casing section in a well bore, a derrick over the rotary table assembly, a crown block at the top of the derrick, a first piston and cylinder subassembly pivotally mounted on one side of the derrick over the rotary table assembly and below the crown block for pivotation about a horizontal axis, a second piston and cylinder subassembly pivotally mounted on a second side of the derrick for pivotation about a horizontal axis. The second piston and cylinder subassembly is located over the rotary table assembly and below the crown block and extends substantially normal to the direction of extension of the first piston and cylinder subassembly. The cooperating casing clamping elements are carried on the piston rods of the first and second piston and cylinder subassemblies, and counter balancing subassemblies are connected to the first and second piston and cylinder subassemblies for pivoting the first and second piston and cylinder subassemblies to a vertically extending inoperative position.

McArthur, J.R.

1984-04-03T23:59:59.000Z

358

Non-axisymmetric wind-accretion simulations. II. Density gradients  

E-Print Network [OSTI]

The hydrodynamics of a variant of classical Bondi-Hoyle-Lyttleton accretion is investigated: a totally absorbing sphere moves at various Mach numbers (3 and 10) relative to a medium, which is taken to be an ideal gas having a density gradient (of 3%, 20% or 100% over one accretion radius) perpendicular to the relative motion. Similarly to the 3D models published previously, both with velocity gradients and without, the models with a density gradient presented here exhibit non-stationary flow patterns, although the Mach cone remains fairly stable. The accretion rates of mass, linear and angular momenta do not fluctuate as strongly as published previously for 2D models. No obvious trend of the dependency of mass accretion rate fluctuations on the density gradient can be discerned. The average specific angular momentum accreted is roughly between zero and 70% of the total angular momentum available in the accretion cylinder in the cases where the average is prograde. Due to the large fluctuations during accretion, the average angular momentum of some models is retrograde by up to 25%. Small gradients hardly influence the average accretion rates as compared to accretion from a homogeneous medium, while very large ones succeed to dominate and form an accretion flow in which the sense of rotation is not inverted.

M. Ruffert

1999-03-19T23:59:59.000Z

359

Measurement of time dependent fields in high gradient superconducting quadrupoles for the Tevatron  

SciTech Connect (OSTI)

Magnetic field measurements have been performed on prototype and production magnets from two high gradient superconducting quadrupoles designs. One design is a double shell quadrupole with 36 strand Rutherford cable. The other design is a single shell quadrupole with 5 individually monolithic strands connected in series. These magnets have similar bore diameters and cable dimensions. However, there are significant differences between the two designs, as well as differences between prototype and production magnets within each design, with regard to Cu to superconductor ratio, filament diameter and filament spacing to strand diameter. The time dependence of fixed currents of the measured magnetic fields is discussed. 9 refs., 6 figs., 1 tab.

Lamm, M.J.; Coulter, K.; Gourlay, S.; Jaffery, T.S.

1990-10-01T23:59:59.000Z

360

Quantitative Spectroscopy of 24 A supergiants in the Sculptor galaxy NGC 300: Flux weighted gravity luminosity relationship, metallicity and metallicity gradient  

E-Print Network [OSTI]

A quantitative spectral analysis of 24 A supergiants in the Sculptor Group spiral galaxy NGC 300 at a distance of 1.9 Mpc is presented. A new method is introduced to analyze low resolution (~5 AE) spectra, which yields metallicities accurate to 0.2 dex including the uncertainties arising from the errors in Teff (5%) and log g (0.2 dex). For the first time the stellar metallicity gradient based on elements such as titanium and iron in a galaxy beyond the Local Group is investigated. Solar metallicity is measured in the center and 0.3 solar in the outskirts and a logarithmic gradient of -0.08 dex/kpc. An average reddening of E(B-V)~0.12 mag is obtained, however with a large variation from 0.07 to 0.24 mag. We also determine stellar radii, luminosities and masses and discuss the evolutionary status. Finally, the observed relationship between absolute bolometric magnitudes M_{bol} and flux weighted gravities g_{F} = g/Teff^4 is investigated. At high temperatures the strengths of the Balmer lines depends solely on the flux-weighted gravity, which allows a precise direct determination of log g_{F} with an accuracy of 0.05 to 0.1 dex. We find a tight relationship between M_{bol} and log g_{F} in agreement with stellar evolution theory. Combining these new results with previous work on Local Group galaxies we obtain a new flux weighted gravity luminosity relationship (FGLR), which is very well defined and appears to be an excellent alternative tool to determine distances to galaxies.

R. -P. Kudritzki; M. A. Urbaneja; F. Bresolin; N. Przybilla; W. Gieren; G. Pietrzynski

2008-03-26T23:59:59.000Z

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Ultra Thin Quantum Well Materials  

SciTech Connect (OSTI)

This project has enabled Hi-Z technology Inc. (Hi-Z) to understand how to improve the thermoelectric properties of Si/SiGe Quantum Well Thermoelectric Materials. The research that was completed under this project has enabled Hi-Z Technology, Inc. (Hi-Z) to satisfy the project goal to understand how to improve thermoelectric conversion efficiency and reduce costs by fabricating ultra thin Si/SiGe quantum well (QW) materials and measuring their properties. In addition, Hi-Z gained critical new understanding on how thin film fabrication increases the silicon substrate's electrical conductivity, which is important new knowledge to develop critical material fabrication parameters. QW materials are constructed with alternate layers of an electrical conductor, SiGe and an electrical insulator, Si. Film thicknesses were varied, ranging from 2nm to 10nm where 10 nm was the original film thickness prior to this work. The optimum performance was determined at a Si and SiGe thickness of 4nm for an electrical current and heat flow parallel to the films, which was an important conclusion of this work. Essential new information was obtained on how the Si substrate electrical conductivity increases by up to an order of magnitude upon deposition of QW films. Test measurements and calculations are accurate and include both the quantum well and the substrate. The large increase in substrate electrical conductivity means that a larger portion of the electrical current passes through the substrate. The silicon substrate's increased electrical conductivity is due to inherent impurities and thermal donors which are activated during both molecular beam epitaxy and sputtering deposition of QW materials. Hi-Z's forward looking cost estimations based on future high performance QW modules, in which the best Seebeck coefficient and electrical resistivity are taken from separate samples predict that the electricity cost produced with a QW module could be achieved at <$0.35/W. This price would open many markets for waste heat recovery applications. By installing Hi-Z's materials in applications in which electricity could be produced from waste heat sources could result in significant energy savings as well as emissions reductions. For example, if QW thermoelectric generators could be introduced commercially in 2015, and assuming they could also capture an additional 0.1%/year of the available waste heat from the aluminum, steel, and iron industries, then by 2020, their use would lead to a 2.53 trillion Btu/year reduction in energy consumption. This translates to a $12.9 million/year energy savings, and 383.6 million lb's of CO2 emissions reduction per year. Additionally, Hi-Z would expect that the use of QW TE devices in the automotive, manufacturing, and energy generation industries would reduce the USA's petroleum and fossil fuel dependence, and thus significantly reduce emissions from CO2 and other polluting gasses such as NOx, SOx, and particulate matter (PM), etc.

Dr Saeid Ghamaty

2012-08-16T23:59:59.000Z

362

Evolutionary and Gradient-Based Algorithms for Lennard-Jones Cluster Optimization  

E-Print Network [OSTI]

gradient method, while Section 3 shows how the asynchronous conjugate gradient method compares and randomized gradient methods with respect to their global search behavior. The randomized gradient method.g., conjugate gra- dient method) is started. With the local minima in- formation, the search is continued

Schraudolph, Nicol N.

363

The Solution of Systems of Linear Equations using the Conjugate Gradient Method  

E-Print Network [OSTI]

The Solution of Systems of Linear Equations using the Conjugate Gradient Method on the Parallel gradient solver on the SPMD­programmable MUSIC­system. We outline the conjugate gradient method, give­associativity of the floating point addition. We investi­ gate the speed of convergence of the conjugate gradient method

Schneider, Jean-Guy

364

Newton-conjugate-gradient methods for solitary wave computations Jianke Yang  

E-Print Network [OSTI]

Newton-conjugate-gradient methods for solitary wave computations Jianke Yang Department's method Conjugate-gradient methods a b s t r a c t In this paper, the Newton-conjugate-gradient methods the linearization operator is self-adjoint, the preconditioned conjugate-gradient method is pro- posed to solve

Yang, Jianke

365

A NONLINEAR CONJUGATE GRADIENT METHOD WITH A STRONG GLOBAL CONVERGENCE PROPERTY  

E-Print Network [OSTI]

A NONLINEAR CONJUGATE GRADIENT METHOD WITH A STRONG GLOBAL CONVERGENCE PROPERTY Y. H. DAI AND Y­182 Abstract. Conjugate gradient methods are widely used for unconstrained optimization, especially large scale gradient methods. This paper presents a new version of the conjugate gradient method, which converges

Yuan, Ya-xiang

366

Algorithm 851: CG DESCENT, a Conjugate Gradient Method with Guaranteed Descent  

E-Print Network [OSTI]

Algorithm 851: CG DESCENT, a Conjugate Gradient Method with Guaranteed Descent WILLIAM W. HAGER In Hager and Zhang [2005] we introduce a new nonlinear conjugate gradient method for solving con- jugate gradient research. The iterates xk, k 0, in conjugate gradient methods satisfy

Zhang, Hongchao

367

A planar ion trap chip with integrated structures for an adjustable magnetic field gradient  

E-Print Network [OSTI]

field necessary for magnetic-gradient- induced coupling between ionic effective spins. We dem- onstrate] magnetic field gradient, however, such coupling is induced. Also, coupling between spin states of different-gradient- induced coupling (MAGIC). A static gradient can be generated by permanent mag- nets [15, 16] or by current

Wunderlich, Christof

368

High temperature corrosion research at the Albany Research Center  

SciTech Connect (OSTI)

The Severe Environment Corrosion and Erosion Research Facility (SECERF) at the Albany Research Center is operational. SECERF consists of 6 modules that share the availability of up to 10 different gases to produce environments for high temperature corrosion and erosion research. Projects to be conducted in the modules include: corrosion sensors for fossil energy systems, thermal gradient effects on high temperature corrosion, the development of sulfidation resistant alloys, determination of the effects of ash on the corrosion of metals and alloys in coal and waste combustion and coal gasification environments, high temperature erosion-corrosion of metals, and molten slag effects on refractories. Results from two areas, the effect of ash deposits on alloy corrosion and thermal gradient effects on the corrosion of metals, will be highlighted. Ash produced in coal gasifiers, coal combustors, and waste combustors, when deposited on metal surfaces, provides sites for corrosion attack and contributes chemical species that participate in the corrosion reaction. Results are presented for the corrosion of 304L stainless steel, that was either uncoated or coated with ash or with ash containing NaCl or Na2SO4, in air-water vapor mixtures at 600 C. The presence of high heat fluxes and temperature gradients in many fossil energy systems creates the need for an understanding of their effects on corrosion and oxidation. Such information would be useful for both improved alloy design and for better translation of isothermal laboratory results to field use. Temperature gradients in a solid oxide result in two changes that modify diffusion within the oxide. The first is when a gradient in point defect concentration is created within the oxide, for example, where more vacancies are expected at a higher temperature. The second change is when the presence of a temperature gradient biases the diffusion jump of an atom. Results of tests are presented for cobalt with metal surface temperatures of approximately 920-950 C in N2 plus 1-10 vol% O2 environments with a heat flux of about 40 kW/m2. Non-equilibrium thermodynamics were used to develop oxidation rate equations in temperature gradients that were combined with point defect information of CoO to predict oxidation rates.

Covino, Bernard S., Jr.; Holcomb, Gordon R.; Russell, James H.; Cramer, Stephen D.; Bullard, Sophie J.; Ziomek-Moroz, Margaret; Matthes, Steven A.; Chinn, R.E.

2002-01-01T23:59:59.000Z

369

Test of Department of Energy Strategic Petroleum Reserve Cavern Bryan Mound 104. [Salt cavern entry wells  

SciTech Connect (OSTI)

This document reports the certification test of Cavern Bryan Mound 104 conducted between September 19 and November 9, 1984. The test included pressurization with oil to near maximum test gradient, depressuring to maximum operating gradient, and doing nitrogen leak tests of the three cavern entry wells. Test results indicate nitrogen loss rates from the wells of 35 bbl/y from 104A, 19 bbl/y from 104B, and 0 bbl/y from 104C. These nitrogen loss rates can reasonably be assumed to correspond to a total cavern oil loss rate of 5.4 bbl/y, which is well within the DOE acceptance criterion of 100 bbl/y of oil per cavern. The final phase of the nitrogen leak test was observed by a representative of the Texas Railroad Commission. 7 refs., 10 figs., 2 tabs.

Goin, K.L.

1985-05-01T23:59:59.000Z

370

Geothermal well log interpretation state of the art. Final report  

SciTech Connect (OSTI)

An in-depth study of the state of the art in Geothermal Well Log Interpretation has been made encompassing case histories, technical papers, computerized literature searches, and actual processing of geothermal wells from New Mexico, Idaho, and California. A classification scheme of geothermal reservoir types was defined which distinguishes fluid phase and temperature, lithology, geologic province, pore geometry, salinity, and fluid chemistry. Major deficiencies of Geothermal Well Log Interpretation are defined and discussed with recommendations of possible solutions or research for solutions. The Geothermal Well Log Interpretation study and report has concentrated primarily on Western US reservoirs. Geopressured geothermal reservoirs are not considered.

Sanyal, S.K.; Wells, L.E.; Bickham, R.E.

1980-01-01T23:59:59.000Z

371

Detection of water or gas entry into horizontal wells by using permanent downhole monitoring systems  

E-Print Network [OSTI]

distributed temperature sensors (DTS) in intelligent completions. Analyzing such changes will potentially aid the diagnosis of downhole flow conditions. In vertical wells, temperature logs have been used successfully to diagnose the downhole flow conditions...

Yoshioka, Keita

2007-09-17T23:59:59.000Z

372

Investigations of low-temperature geothermal potential in New York State  

SciTech Connect (OSTI)

Temperature gradient map and published heat flow data indicate a possible potential for a geothermal resource in western and central New York State. A new analysis of bottom-hole temperature data for New York State confirms the existence of three positive gradient anomalies: the East Aurora, Cayuga, and Elmira anomalies, with gradients as high as 32/sup 0/C/km, 36/sup 0/C/km, and 36/sup 0/C/km, respectively. Ground waters from two of these anomalies are enriched in silica relative to surrounding areas. Heat flows based on silica geothermometry are 50 to 70 mWm/sup -2/ for the anomalies and 41.4 mWm/sup -2/ for bordering regional flux. A correlation between Bouguer gravity anomalies and the temperature gradient map suggests that the geothermal anomalies may occur above radioactive granites in the basement.

Hodge, D.S.; De Rito, R.; Hifiker, K.; Morgan, P.; Swanberg, C.A.

1981-09-01T23:59:59.000Z

373

Gradient isolator for flow field of fuel cell assembly  

DOE Patents [OSTI]

Isolator(s) include isolating material and optionally gasketing material strategically positioned within a fuel cell assembly. The isolating material is disposed between a solid electrolyte and a metal flow field plate. Reactant fluid carried by flow field plate channel(s) forms a generally transverse electrochemical gradient. The isolator(s) serve to isolate electrochemically a portion of the flow field plate, for example, transversely outward from the channel(s), from the electrochemical gradient. Further, the isolator(s) serve to protect a portion of the solid electrolyte from metallic ions.

Ernst, William D. (Troy, NY)

1999-01-01T23:59:59.000Z

374

Velocity bunching in travelling wave accelerator with low acceleration gradient  

E-Print Network [OSTI]

We present the analytical and simulated results concerning the influences of the acceleration gradient in the velocity bunching process, which is a bunch compression scheme that uses a traveling wave accelerating structure as a compressor. Our study shows that the bunch compression application with low acceleration gradient is more tolerant to phase jitter and more successful to obtain compressed electron beam with symmetrical longitudinal distribution and low energy spread. We also present a transverse emittance compensation scheme to compensate the emittance growth caused by the increasing of the space charge force in the compressing process that is easy to be adjusted for different compressing factors.

Huang, Rui-Xuan; Li, Wei-Wei; Jia, Qi-Ka

2013-01-01T23:59:59.000Z

375

Discontinuous Galerkin finite element methods for gradient plasticity.  

SciTech Connect (OSTI)

In this report we apply discontinuous Galerkin finite element methods to the equations of an incompatibility based formulation of gradient plasticity. The presentation is motivated with a brief overview of the description of dislocations within a crystal lattice. A tensor representing a measure of the incompatibility with the lattice is used in the formulation of a gradient plasticity model. This model is cast in a variational formulation, and discontinuous Galerkin machinery is employed to implement the formulation into a finite element code. Finally numerical examples of the model are shown.

Garikipati, Krishna. (University of Michigan, Ann Arbor, MI); Ostien, Jakob T.

2010-10-01T23:59:59.000Z

376

Gradients of meteorological parameters in convective and nonconvective areas  

E-Print Network [OSTI]

. SYNOPTIC CONDITIONS 4. STRATIFICATION OF DATA 5. COMPUTATIONAL PROCEDURES 21 25 a. Gridding of rawinsonde data 25 b. Gradients 26 5'' lp t* 27 RESULTS 29 a. Gradients 29 1) Convective areas 29 2) Nonconvective areas 31 3) Combined areas 33 vi... air turbulence. By using airplane data from over the western United States, Scoggins (1975) has shown that CAT at 300 mb occurred 71% of the time when the magnitude of the vector horizontal wind shear -5 -1 exceeded 4. 5 x 10 sec . The horizontal...

McCown, Milton Samuel

1976-01-01T23:59:59.000Z

377

Gradient isolator for flow field of fuel cell assembly  

DOE Patents [OSTI]

Isolator(s) include isolating material and optionally gasketing material strategically positioned within a fuel cell assembly. The isolating material is disposed between a solid electrolyte and a metal flow field plate. Reactant fluid carried by flow field plate channel(s) forms a generally transverse electrochemical gradient. The isolator(s) serve to isolate electrochemically a portion of the flow field plate, for example, transversely outward from the channel(s), from the electrochemical gradient. Further, the isolator(s) serve to protect a portion of the solid electrolyte from metallic ions. 4 figs.

Ernst, W.D.

1999-06-15T23:59:59.000Z

378

On Higuchi Ghosts and Gradient Instabilities in Bimetric Gravity  

E-Print Network [OSTI]

We discuss the conditions to satisfy the Higuchi bound and to avoid gradient instabilities in the scalar sector for cosmological solutions in singly coupled bimetric gravity theories. We find that in expanding universes the ratio of the scale factors of the reference and observable metric has to increase at all times. This automatically implies a ghost-free helicity-2 sector and enforces a phantom Dark Energy. Furthermore, the condition for the absence of gradient instabilities in the scalar sector will be analyzed. Finally, we discuss whether cosmological solutions, including exotic evolutions like bouncing cosmologies, can exist, in which both the Higuchi ghost and scalar instabilities are absent at all times.

Könnig, Frank

2015-01-01T23:59:59.000Z

379

Development of Robust Analog and Mixed-Signal Circuits in the Presence of Process- Voltage-Temperature Variations  

E-Print Network [OSTI]

for transconductance amplifiers.................................7 I.2.2. Process variation-aware quantization ...........................................................8 I.2.3. Non-invasive on-chip measurement of thermal gradients and RF power.....9 I.2.4. Analog... .....................................................................................107 V. AN ON-CHIP TEMPERATURE SENSOR TO MEASURE RF POWER DISSIPATION AND THERMAL GRADIENTS.....................................................109 V.1. Background...

Onabajo, Marvin Olufemi

2012-07-16T23:59:59.000Z

380

Spatially indirect excitons in coupled quantum wells  

SciTech Connect (OSTI)

Microscopic quantum phenomena such as interference or phase coherence between different quantum states are rarely manifest in macroscopic systems due to a lack of significant correlation between different states. An exciton system is one candidate for observation of possible quantum collective effects. In the dilute limit, excitons in semiconductors behave as bosons and are expected to undergo Bose-Einstein condensation (BEC) at a temperature several orders of magnitude higher than for atomic BEC because of their light mass. Furthermore, well-developed modern semiconductor technologies offer flexible manipulations of an exciton system. Realization of BEC in solid-state systems can thus provide new opportunities for macroscopic quantum coherence research. In semiconductor coupled quantum wells (CQW) under across-well static electric field, excitons exist as separately confined electron-hole pairs. These spatially indirect excitons exhibit a radiative recombination time much longer than their thermal relaxation time a unique feature in direct band gap semiconductor based structures. Their mutual repulsive dipole interaction further stabilizes the exciton system at low temperature and screens in-plane disorder more effectively. All these features make indirect excitons in CQW a promising system to search for quantum collective effects. Properties of indirect excitons in CQW have been analyzed and investigated extensively. The experimental results based on time-integrated or time-resolved spatially-resolved photoluminescence (PL) spectroscopy and imaging are reported in two categories. (i) Generic indirect exciton systems: general properties of indirect excitons such as the dependence of exciton energy and lifetime on electric fields and densities were examined. (ii) Quasi-two-dimensional confined exciton systems: highly statistically degenerate exciton systems containing more than tens of thousands of excitons within areas as small as (10 micrometer){sup 2} were observed. The spatial and energy distributions of optically active excitons were used as thermodynamic quantities to construct a phase diagram of the exciton system, demonstrating the existence of distinct phases. Optical and electrical properties of the CQW sample were examined thoroughly to provide deeper understanding of the formation mechanisms of these cold exciton systems. These insights offer new strategies for producing cold exciton systems, which may lead to opportunities for the realization of BEC in solid-state systems.

Lai, Chih-Wei Eddy

2004-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Fluid-Rock Characterization and Interactions in NMR Well Logging  

SciTech Connect (OSTI)

The objective of this report is to characterize the fluid properties and fluid-rock interactions that are needed for formation evaluation by NMR well logging. The advances made in the understanding of NMR fluid properties are summarized in a chapter written for an AAPG book on NMR well logging. This includes live oils, viscous oils, natural gas mixtures, and the relation between relaxation time and diffusivity. Oil based drilling fluids can have an adverse effect on NMR well logging if it alters the wettability of the formation. The effect of various surfactants on wettability and surface relaxivity are evaluated for silica sand. The relation between the relaxation time and diffusivity distinguishes the response of brine, oil, and gas in a NMR well log. A new NMR pulse sequence in the presence of a field gradient and a new inversion technique enables the T{sub 2} and diffusivity distributions to be displayed as a two-dimensional map. The objectives of pore morphology and rock characterization are to identify vug connectivity by using X-ray CT scan, and to improve NMR permeability correlation. Improved estimation of permeability from NMR response is possible by using estimated tortuosity as a parameter to interpolate between two existing permeability models.

George J. Hirasaki; Kishore K. Mohanty

2005-09-05T23:59:59.000Z

382

Heating of Oil Well by Hot Water Circulation  

E-Print Network [OSTI]

When highly viscous oil is produced at low temperatures, large pressure drops will significantly decrease production rate. One of possible solutions to this problem is heating of oil well by hot water recycling. We construct and analyze a mathematical model of oil-well heating composed of three linear parabolic PDE coupled with one Volterra integral equation. Further on we construct numerical method for the model and present some simulation results.

Mladen Jurak; Zarko Prnic

2005-03-04T23:59:59.000Z

383

Polymer-cement geothermal-well-completion materials. Final report  

SciTech Connect (OSTI)

A program to develop high-temperature polymer cements was performed. Several formulations based on organic and semi-inorganic binders were evaluated on the basis of mechanical and thermal stability, and thickening time. Two optimized systems exhibited properties exceeding those required for use in geothermal wells. Both systems were selected for continued evaluation at the National Bureau of Standards and contingent upon the results, for field testing in geothermal wells.

Zeldin, A.N.; Kukacka, L.E.

1980-07-01T23:59:59.000Z

384

Computing several eigenpairs of Hermitian problems by conjugate gradient iterations  

SciTech Connect (OSTI)

The paper is concerned with algorithms for computing several extreme eigenpairs of Hermitian problems based on the conjugate gradient method. We analyse computational strategies employed by various algorithms of this kind reported in the literature and identify their limitations. Our criticism is illustrated by numerical tests on a set of problems from electronic structure calculations and acoustics.

Ovtchinnikov, E.E. [Harrow School of Computer Science, University of Westminster, Watford Road, Northwick Park, London HA1 3TP (United Kingdom)], E-mail: e_ovtchinnikov@hotmail.com

2008-11-20T23:59:59.000Z

385

BIOGEOCHEMICAL GRADIENTS AS A FRAMEWORK FOR UNDERSTANDING WASTE SITE EVOLUTION  

SciTech Connect (OSTI)

The migration of biogeochemical gradients is a useful framework for understanding the evolution of biogeochemical conditions in groundwater at waste sites contaminated with metals and radionuclides. This understanding is critical to selecting sustainable remedies and evaluating sites for monitored natural attenuation, because most attenuation mechanisms are sensitive to geochemical conditions such as pH and redox potential. Knowledge of how gradients in these parameters evolve provides insights into the behavior of contaminants with time and guides characterization, remedy selection, and monitoring efforts. An example is a seepage basin site at the Savannah River Site in South Carolina where low-level acidic waste has seeped into groundwater. The remediation of this site relies, in part, on restoring the natural pH of the aquifer by injecting alkaline solutions. The remediation will continue until the pH up-flow of the treatment zone increases to an acceptable value. The time required to achieve this objective depends on the time it takes the trailing pH gradient, the gradient separating the plume from influxing natural groundwater, to reach the treatment zone. Predictions of this length of time will strongly influence long-term remedial decisions.

Denham, M; Karen Vangelas, K

2008-10-17T23:59:59.000Z

386

Soil macroaggregate dynamics in a mountain spatial climate gradient  

E-Print Network [OSTI]

Soil macroaggregate dynamics in a mountain spatial climate gradient Lauric Cécillon1,2,* , Nilvania://lauric.cecillon.free.fr/ Key words: Mountain soils; Climate change; Soil aggregation; Soil organic matter; Near infrared reflectance spectroscopy; Soil threats Biogeochemistry 97: 31-43 (2010) http://dx.doi.org/10.1007/s10533

Paris-Sud XI, Université de

387

Gradient Improvement by Removal of Identified Local Defects  

SciTech Connect (OSTI)

Recent experience of ILC cavity processing and testing at Jefferson Lab has shown that some 9-cell cavities are quench limited at a gradient in the range of 15-25 MV/m. Further studies reveal that these quench limits are often correlated with sub-mm sized and highly localized geometrical defects at or near the equator weld. There are increasing evidence to show that these genetic defects have their origin in the material or in the electron beam welding process (for example due to weld irregularities or splatters on the RF surface and welding porosity underneath the surface). A local defect removal method has been proposed at Jefferson Lab by locally re-melting the niobium material. Several 1-cell cavities with known local defects have been treated by using the JLab local e-beam re-melting method, resulting in gradient and Q0 improvement. We also sent 9-cell cavities with known gradient limiting local defects to KEK for local grinding and to FNAL for global mechanical polishing. We report on the results of gradient improvements by removal of local defects in these cavities.

R.L. Geng, W.A. Clemens, C.A. Cooper, H. Hayano, K. Watanabe

2011-07-01T23:59:59.000Z

388

Online gradient descent learning algorithms Yiming Ying and Massimiliano Pontil  

E-Print Network [OSTI]

Online gradient descent learning algorithms Yiming Ying and Massimiliano Pontil Department of Computer Science, University College London Gower Street, London, WC1E 6BT, England, UK {y.ying, m, 62L20. Contact author: Yiming Ying, Telephone: +44 (0)20 7387 0374, Fax: +44 (0)20 7387 1397 1 #12

Pontil, Massimiliano

389

Online gradient descent learning algorithm Yiming Ying and Massimiliano Pontil  

E-Print Network [OSTI]

Online gradient descent learning algorithm Yiming Ying and Massimiliano Pontil Department of Computer Science, University College London Gower Street, London, WC1E 6BT, England, UK {y.ying, m Numbers: 68Q32, 68T05, 62J02, 62L20. Contact author: Yiming Ying, Telephone: +44 (0)20 7679 0374, Fax

Ying, Yiming

390

Simulation of IPA Gradients in Hybrid Network Systems Benjamin Melamed  

E-Print Network [OSTI]

Simulation of IPA Gradients in Hybrid Network Systems Benjamin Melamed Rutgers University Rutgers Atlanta, GA 30332 October 26, 2005 Abstract Infinitesimal Perturbation Analysis (IPA) provides formulas paths of stochastic systems. In practice, IPA derivatives may be computed either from simulation runs

391

Seasonal mass balance gradients in Norway L. A. Rasmussen1  

E-Print Network [OSTI]

16 Aug 05 Seasonal mass balance gradients in Norway L. A. Rasmussen1 and L. M. Andreassen2 1 Norwegian Water Resources and Energy Directorate (NVE) P. O. Box 5091 Majorstua, N-0301 Oslo, Norway in Norway exists in their profiles of both seasonal balances, winter bw(z) and summer bs(z). Unlike many

Rasmussen, L.A.

392

The Urban Environmental Gradient: Anthropogenic Influences on the  

E-Print Network [OSTI]

Georgia, through Atlanta, to the Gulf of Mexico and reflects a steep gradient in population density from as vehicular traffic. Introduction Many of the common anthropogenic pollution problems are focused in urban geographic areas. Suburbia does not contribute much by way of industrial pollution, but it does serve

393

Continuous Edge Gradient-Based Template Matching for Articulated  

E-Print Network [OSTI]

Zachmann IfI Technical Report Series IfI-09-01 #12;Impressum Publisher: Institut für Informatik, Technische (Technical Computer Science) Prof. Dr. Gabriel Zachmann (Computer Graphics) #12;Continuous Edge Gradient-Based Template Matching for Articulated Objects Daniel Mohr and Gabriel Zachmann Abstract Detection

Zachmann, Gabriel

394

Non-axisymmetric wind-accretion simulations; 2, Density gradients  

E-Print Network [OSTI]

The hydrodynamics of a variant of classical Bondi-Hoyle-Lyttleton accretion is investigated: a totally absorbing sphere moves at various Mach numbers (3 and 10) relative to a medium, which is taken to be an ideal gas having a density gradient (of 3%, 20% or 100% over one accretion radius) perpendicular to the relative motion. Similarly to the 3D models published previously, both with velocity gradients and without, the models with a density gradient presented here exhibit non-stationary flow patterns, although the Mach cone remains fairly stable. The accretion rates of mass, linear and angular momenta do not fluctuate as strongly as published previously for 2D models. No obvious trend of the dependency of mass accretion rate fluctuations on the density gradient can be discerned. The average specific angular momentum accreted is roughly between zero and 70% of the total angular momentum available in the accretion cylinder in the cases where the average is prograde. Due to the large fluctuations during accretio...

Ruffert, M

1999-01-01T23:59:59.000Z

395

A distributed accelerated gradient algorithm for distributed model predictive  

E-Print Network [OSTI]

of hydro power plants is to manage the available water resources efficiently, while following an optimal is applied to the power reference tracking problem of a hydro power valley (HPV) system. The applied power control, Distributed optimization, Accelerated gradient algorithm, Model predictive control

Como, Giacomo

396

A study of microbend test by strain gradient plasticity  

E-Print Network [OSTI]

A study of microbend test by strain gradient plasticity W. Wanga , Y. Huangb, *, K.J. Hsiac , K with plastic deformation is on the order of microns. This size effect cannot be explained by classical plasticity theories since their constitutive relations do not have an intrinsic material length. Strain

Hsia, K Jimmy

397

Treated Wastewater Effluent Reduces Sperm Motility Along an Osmolality Gradient  

E-Print Network [OSTI]

Treated Wastewater Effluent Reduces Sperm Motility Along an Osmolality Gradient H. L. Schoenfuss Ã? 2008 Ã? Springer Science+Business Media, LLC 2008 Abstract Many toxic effects of treated wastewater environment of treated wastewater effluent frequently differs consider- ably from that of its receiving waters

Julius, Matthew L.

398

Observation of pressure gradient and related flow rate effect on the plasma parameters in plasma processing reactor  

SciTech Connect (OSTI)

In industrial plasma processes, flow rate has been known to a key to control plasma processing results and has been discussed with reactive radical density, gas residence time, and surface reaction. In this study, it was observed that the increase in the flow rate can also change plasma parameters (electron temperature and plasma density) and electron energy distribution function in plasma processing reactor. Based on the measurement of gas pressure between the discharge region and the pumping port region, the considerable differences in the gas pressure between the two regions were found with increasing flow rate. It was also observed that even in the discharge region, the pressure gradient occurs at the high gas flow rate. This result shows that increasing the flow rate results in the pressure gradient and causes the changes in the plasma parameters.

Lee, Hyo-Chang; Kim, Aram; Chung, Chin-Wook [Department of Electrical Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea, Republic of); Moon, Se Youn [Solar Energy Group, LG Electronics Advanced Research Institute, 16 Woomyeon-Dong, Seocho-Gu, Seoul 137-724 (Korea, Republic of)

2011-02-15T23:59:59.000Z

399

Beamline Temperatures  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAboutScience ProgramBackground8.0.1 PrintTemperatures Energy: 3.0000 GeV

400

Estimating Temperature Distributions In Geothermal Areas Using...  

Open Energy Info (EERE)

neuronet temperature estimates based on well log data derive from: (a) the neuronet "education level" (which depends on the amount and structure of information used for teaching)...

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Production Well Performance Enhancement using Sonication Technology  

SciTech Connect (OSTI)

The objective of this project was to develop a sonic well performance enhancement technology that focused on near wellbore formation damage. In order to successfully achieve this objective, a three-year project was defined. The entire project was broken into four tasks. The overall objective of all this was to foster a better understanding of the mechanisms involved in sonic energy interactions with fluid flow in porous media and adapt such knowledge for field applications. The fours tasks are: • Laboratory studies • Mathematical modeling • Sonic tool design and development • Field demonstration The project was designed to be completed in three years; however, due to budget cuts, support was only provided for the first year, and hence the full objective of the project could not be accomplished. This report summarizes what was accomplished with the support provided by the US Department of Energy. Experiments performed focused on determining the inception of cavitation, studying thermal dissipation under cavitation conditions, investigating sonic energy interactions with glass beads and oil, and studying the effects of sonication on crude oil properties. Our findings show that the voltage threshold for onset of cavitation is independent of transducer-hydrophone separation distance. In addition, thermal dissipation under cavitation conditions contributed to the mobilization of deposited paraffins and waxes. Our preliminary laboratory experiments suggest that waxes are mobilized when the fluid temperature approaches 40°C. Experiments were conducted that provided insights into the interactions between sonic wave and the fluid contained in the porous media. Most of these studies were carried out in a slim-tube apparatus. A numerical model was developed for simulating the effect of sonication in the nearwellbore region. The numerical model developed was validated using a number of standard testbed problems. However, actual application of the model for scale-up purposes was limited due to funding constraints. The overall plan for this task was to perlorm field trials with the sonication tooL These trials were to be performed in production and/or injection wells located in Pennsylvania, New York, and West Virginia. Four new wells were drilled in preparation for the field demonstration. Baseline production data were collected and reservoir simulator tuned to simulate these oil reservoirs. The sonication tools were designed for these wells. However, actual field testing could not be carried out because of premature termination of the project.

Adewumi, Michael A; Ityokumbul, M Thaddeus; Watson, Robert W; Eltohami, Eltohami; Farias, Mario; Heckman, Glenn; Houlihan, Brendan; Karoor, Samata Prakash; Miller, Bruce G; Mohammed, Nazia; Olanrewaju, Johnson; Ozdemir, Mine; Rejepov, Dautmamed; Sadegh, Abdallah A; Quammie, Kevin E; Zaghloul, Jose; Hughes, W Jack; Montgomery, Thomas C

2005-12-31T23:59:59.000Z

402

Low-to-moderate temperature geothermal resource assessment for Nevada, area specific studies. Final report, June 1, 1980-August 30, 1981  

SciTech Connect (OSTI)

The Hawthorne study area is located in Mineral County, Nevada and surrounds the municipality of the same name. It encompasses an area of approximately 310 sq. km (120 sq. mi), and most of the land belongs to the US Army Ammunition Plant. The energy needs of the military combined with those of the area population (over 5,000 residents) are substantial. The area is classified as having a high potential for direct applications using the evaluation scheme described in Texler and others (1979). A variety of scientific techniques was employed during area-wide resource assessment. General geologic studies demonstrate the lithologic diversity in the area; these studies also indicate possible sources for dissolved fluid constituents. Geophysical investigations include aero-magnetic and gravity surveys which aid in defining the nature of regional, and to a lesser extent, local variations in subsurface configurations. Surface and near-surface structural features are determined using various types of photo imagery including low sun-angle photography. An extensive shallow depth temperature probe survey indicates two zones of elevated temperature on opposite sides of the Walker Lake basin. Temperature-depth profiles from several wells in the study area indicate significant thermal fluid-bearing aquifers. Fluid chemical studies suggest a wide spatial distribution for the resource, and also suggest a meteoric recharge source in the Wassuk Range. Finally, a soil-mercury survey was not a useful technique in this study area. Two test holes were drilled to conclude the area resource assessment, and thermal fluids were encountered in both wells. The western well has measured temperatures as high as 90 C (194 F) within 150 meters (500 ft) of the surface. Temperature profiles in this well indicate a negative temperature gradient below 180 meters (590 ft). The eastern hole had a bottom hole temperature of 61 C (142 F) at a depth of only 120 meters (395 ft). A positive gradient is observed to a total depth in the well. Several conclusions are drawn from this study: the resource is distributed over a relatively large area; resource fluid temperatures can exceed 90 C (194 F), but are probably limited to a maximum of 125 C (257 F); recharge to the thermal system is meteoric, and flow of the fluids in the near surface (< 500 m) is not controlled by faults; heat supplied to the system may be related to a zone of partially melted crustal rocks in the area 25 km (15 mi) south of Hawthorne. Four papers and an introduction are included. A separate abstract was prepared for each paper. (MHR)

Trexler, D.T.; Koenig, B.A.; Flynn, T.; Bruce, J.L.; Ghusn, G. Jr.

1981-01-01T23:59:59.000Z

403

Chemical analyses of selected thermal springs and wells in Wyoming  

SciTech Connect (OSTI)

Basic chemical data for 27 selected thermal well and springs in Wyoming are presented. The samples were gathered from 1979 through 1982 in an effort to define geothermal resources in Wyoming. The basic data for the 27 analyzed samples generally include location, temperature, flow, date analyzed, and a description of what the sample is from. The chemical analyses for the sample are listed.

Heasler, H.P.

1984-06-01T23:59:59.000Z

404

NON-STATIONARY TEMPERATURE STRESSES IN THE INDUSTRIAL STEAM TURBINE ROTOR  

E-Print Network [OSTI]

The usage of industrial steam turbines in different industrial branches (chemistry, petrochemistry, refineries, sugar and ethanol plants, etc.) for a generator drive for electricity generation or a mechanical drive for compressors, blowers and pumps, is characterized by the need for high flexibility of operation. High flexibility includes numerous start-ups, shut-downs and power changes during the useful life. Changes in power and steam mass flow lead to changes of the working fluid state in the single turbine stages, and thus their aerodynamic and thermodynamic characteristics. During these transient working regimes in steam turbine rotors, large space and time-dependent temperature gradients appear, which can result in high non-stationary temperature stresses, i.e. increased local stress concentrations, what has a negative impact on the useful life of the rotor. In the worst case they can cause fracture of the turbine rotor. Today, for the determination of thermal stressed state of the steam turbine parts the user softwares based on numerical methods are used. In this paper the results of numerical modelling and calculations of non-stationary temperature fields and related stresses in the rotor of industrial steam turbine of 35 MW power during transient operating regime (a cold startup) will be presented. The results of the calculations serve for estimation of the transient regime impact on the stresses of the rotor, as well as on its entire useful life. Key words: industrial steam turbine, transient regimes, temperature stresses, numerical modelling 1.

Zvonimir Guzovi?; Krešimir Kova?i?; Tihomir Mihali?

405

Experimental Observation of the Inverse Spin Hall Effect at Room Temperature  

SciTech Connect (OSTI)

We observe the inverse spin Hall effect in a two-dimensional electron gas confined in Al-GaAs/InGaAs quantum wells. Specifically, they find that an inhomogeneous spin density induced by the optical injection gives rise to an electric current transverse to both the spin polarization and its gradient. The spin Hall conductivity can be inferred from such a measurement through the Einstein relation and the onsager relation, and is found to have the order of magnitude of 0.5(e{sup 2}/h). The observation is made at the room temperature and in samples with macroscopic sizes, suggesting that the inverse spin Hall effects is a robust macroscopic transport phenomenon.

Liu, Baoli; Shi, Junren; Wang, Wenxin; Zhao, Hongming; Li, Dafang; /Beijing, Inst. Phys.; Zhang, Shoucheng; /Stanford U., Phys. Dept.; Xue, Qikun; Chen, Dongmin; /Beijing, Inst. Phys.

2010-03-16T23:59:59.000Z

406

Daily results of the initial operation of the Los Alamos salt-gradient solar pond  

SciTech Connect (OSTI)

The results of analysis of the initial data obtained on the Los Alamos National Laboratory salt-gradient solar pond, a 232 m/sup 2/ pond constructed for the primary purpose of studying pond hydrodynamics, are presented. The pond and the data-acquisition system were complete and in full operation by August 14, 1982. By September 21, 1982, the lower convecting zone had reached a temperature of 56/sup 0/C. An energy balance was performed over this period and is presented. Soil conductivity determinations have been made from the data, and the method is discussed. As a result of a leak discovered in the pond in September, a method of determining the leak rate was developed, and the results are included.

Hedstrom, J.C.; Jones, G.F.; Meyer, K.A.

1983-01-01T23:59:59.000Z

407

Diffusion-assisted selective dynamical recoupling: A new approach to measure background gradients in magnetic resonance  

SciTech Connect (OSTI)

Dynamical decoupling, a generalization of the original NMR spin-echo sequence, is becoming increasingly relevant as a tool for reducing decoherence in quantum systems. Such sequences apply non-equidistant refocusing pulses for optimizing the coupling between systems, and environmental fluctuations characterized by a given noise spectrum. One such sequence, dubbed Selective Dynamical Recoupling (SDR) [P. E. S. Smith, G. Bensky, G. A. Álvarez, G. Kurizki, and L. Frydman, Proc. Natl. Acad. Sci. 109, 5958 (2012)], allows one to coherently reintroduce diffusion decoherence effects driven by fluctuations arising from restricted molecular diffusion [G. A. Álvarez, N. Shemesh, and L. Frydman, Phys. Rev. Lett. 111, 080404 (2013)]. The fully-refocused, constant-time, and constant-number-of-pulses nature of SDR also allows one to filter out “intrinsic” T{sub 1} and T{sub 2} weightings, as well as pulse errors acting as additional sources of decoherence. This article explores such features when the fluctuations are now driven by unrestricted molecular diffusion. In particular, we show that diffusion-driven SDR can be exploited to investigate the decoherence arising from the frequency fluctuations imposed by internal gradients. As a result, SDR presents a unique way of probing and characterizing these internal magnetic fields, given an a priori known free diffusion coefficient. This has important implications in studies of structured systems, including porous media and live tissues, where the internal gradients may serve as fingerprints for the system's composition or structure. The principles of this method, along with full analytical solutions for the unrestricted diffusion-driven modulation of the SDR signal, are presented. The potential of this approach is demonstrated with the generation of a novel source of MRI contrast, based on the background gradients active in an ex vivo mouse brain. Additional features and limitations of this new method are discussed.

Álvarez, Gonzalo A.; Shemesh, Noam; Frydman, Lucio, E-mail: lucio.frydman@weizmann.ac.il [Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100 (Israel)] [Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100 (Israel)

2014-02-28T23:59:59.000Z

408

Overview of high gradient SRF R&D for ILC cavities at Jefferson Lab  

SciTech Connect (OSTI)

We report the progress on high gradient R&D of ILC cavities at Jefferson Lab (JLab) since the Beijing workshop. Routine 9-cell cavity electropolishing (EP) processing and RF testing has been enhanced with added surface mapping and T-mapping instrumentations. 12 new 9-cell cavities (10 of them are baseline fine-grain TESLA-shape cavities: 5 built by ACCEL/Research Instruments, 4 by AES and 1 by JLab; 2 of them are alternative cavities: 1 fine-grain ICHIRO-shape cavity built by KEK/Japan industry and 1 large-grain TESLA-shape cavity built by JLab) are EP processed and tested. 76 EP cycles are accumulated, corresponding to more than 200 hours of active EP time. Field emission (FE) and quench behaviors of electropolished 9-cell cavities are studied. EP process continues to be optimized, resulting in advanced procedures and hence improved cavity performance. Several 9-cell cavities reached 35 MV/m after the first light EP processing. FE-free performance has been demonstrated in 9-cell cavities in 35-40 MV/m range. 1-cell cavity studies explore new techniques for defect removal as well as advanced integrated cavity processing. Surface studies of niobium samples electropolished together with real cavities provide new insight into the nature of field emitters. Close cooperation with the US cavity fabrication industry has been undertaking with the successful achievement of 41 MV/m for the first time in a 9-cell ILC cavity built by AES. As the size of the data set grows, it is now possible to construct gradient yield curves, from which one can see that significant progress has been made in raising the high gradient yield.

Geng, Rongli [JLAB

2009-11-01T23:59:59.000Z

409

EA-1758: Final Environmental Assessment  

Broader source: Energy.gov [DOE]

Drilling, Testing, and Monitoring of up to 12 Temperature Gradient/Passive Seismic Geothermal Exploratory Wells

410

Health and Wellness Guide for Students Introduction  

E-Print Network [OSTI]

dimensions of health and wellness. The 7 dimensions are: Physical Wellness ­ Taking care of your body Wellness ­ Taking care of what's around you 2Health andWellness Guide for Students #12;Physical Wellness · Communicate with your partner if you have questions or concerns · Meet with a Health Care Provider on campus

411

Fabrication process for a gradient index x-ray lens  

DOE Patents [OSTI]

A process for fabricating high efficiency x-ray lenses that operate in the 0.5-4.0 keV region suitable for use in biological imaging, surface science, and x-ray lithography of integrated circuits. The gradient index x-ray optics fabrication process broadly involves co-sputtering multi-layers of film on a wire, followed by slicing and mounting on block, and then ion beam thinning to a thickness determined by periodic testing for efficiency. The process enables the fabrication of transmissive gradient index x-ray optics for the 0.5-4.0 keV energy range. This process allows the fabrication of optical elements for the next generation of imaging and x-ray lithography instruments m the soft x-ray region.

Bionta, Richard M. (Livermore, CA); Makowiecki, Daniel M. (Livermore, CA); Skulina, Kenneth M. (Livermore, CA)

1995-01-01T23:59:59.000Z

412

Gradient instabilities of electromagnetic waves in Hall thruster plasma  

SciTech Connect (OSTI)

This paper presents a linear analysis of gradient plasma instabilities in Hall thrusters. The study obtains and analyzes the dispersion equation of high-frequency electromagnetic waves based on the two-fluid model of a cold plasma. The regions of parameters corresponding to unstable high frequency modes are determined and the dependence of the increments and intrinsic frequencies on plasma parameters is obtained. The obtained results agree with those of previously published studies.

Tomilin, Dmitry [Department of Electrophysics, Keldysh Research Centre, Moscow 125438 (Russian Federation)

2013-04-15T23:59:59.000Z

413

Determination of dispersivities from a natural-gradient dispersion test  

E-Print Network [OSTI]

, and radioactive wastes. Contaminant hydrogeology is presently a focal point in the realm of hydrologic modeling. Generally, models are designed to represent simplified versions of reality and The style and format of this document was taken from the Journal... dispersivities, v ia a graphical approach, from a natural-gradient dispersion test in which artificial pollution was injected into an aquifer. The dispersion test was conducted by Sud icky et al. (1983) in order to characterize the dispersive properties...

Hoover, Caroline Marie

1985-01-01T23:59:59.000Z

414

Novel geometry gradient coils for MRI designed by genetic algorithm  

E-Print Network [OSTI]

in the Steady State High Performance Computing Facility Herchel Smith Laboratory for Medicinal Chemistry Message Passing Interface Magnetic Resonance Imaging Positron Emission Tomography Radio frequency Electro-motive force Root mean squared IX & x... by the intro­ duction of high performance computing. One of the major disadvantages of this approach . to gradient design is the amount of time taken to produce results, and high performance computing has the potential to reduce this. The amount by which a...

Williams, Guy Barnett

2001-06-19T23:59:59.000Z

415

PATTERNS OF LEAF WETTABILITY ALONG AN EXTREME MOISTURE GRADIENT IN WESTERN PATAGONIA, ARGENTINA  

E-Print Network [OSTI]

PATTERNS OF LEAF WETTABILITY ALONG AN EXTREME MOISTURE GRADIENT IN WESTERN PATAGONIA, ARGENTINA Patagonia, Argentina. Morphological and structural characteristics of leaves significantly affected leaf surfaces. Keywords: leaf wetness, morphology, water droplet, Patagonia, gradient. Introduction A large

Brewer, Carol

416

Creation of nonlinear density gradients for use in internal wave research  

E-Print Network [OSTI]

A method was developed to create a nonlinear density gradient in a tank of water. Such gradients are useful for studying internal waves, an ocean phenomenon that plays an important role in climate and ocean circulation. ...

Harris, Victoria Siân

2007-01-01T23:59:59.000Z

417

An evaluation of subsea pump technologies that can be used to achieve dual gradient drilling  

E-Print Network [OSTI]

Dual Gradient Drilling is an exciting technology which promises to solve the current technical hurdles and economic risks of Deepwater Drilling. Several techniques for Dual Gradient Drilling have been proposed to the industry. One such method...

Oluwadairo, Tolulope

2009-05-15T23:59:59.000Z

418

Generating spatially and temporally controllable long-range concentration gradients in a microfluidic device  

E-Print Network [OSTI]

Concentration gradients have important applications in chemical and biological studies. Here we have achieved rapid generation of spatially and temporally controllable concentration gradients of diffusible molecules (i.e. ...

Vidula, Mahesh K.

419

IMPROVED NATURAL GAS STORAGE WELL REMEDIATION  

SciTech Connect (OSTI)

This report summarizes the research conducted during Budget Period One on the project ''Improved Natural Gas Storage Well Remediation''. The project team consisted of Furness-Newburge, Inc., the technology developer; TechSavants, Inc., the technology validator; and Nicor Technologies, Inc., the technology user. The overall objectives for the project were: (1) To develop, fabricate and test prototype laboratory devices using sonication and underwater plasma to remove scale from natural gas storage well piping and perforations; (2) To modify the laboratory devices into units capable of being used downhole; (3) To test the capability of the downhole units to remove scale in an observation well at a natural gas storage field; (4) To modify (if necessary) and field harden the units and then test the units in two pressurized injection/withdrawal gas storage wells; and (5) To prepare the project's final report. This report covers activities addressing objectives 1-3. Prototype laboratory units were developed, fabricated, and tested. Laboratory testing of the sonication technology indicated that low-frequency sonication was more effective than high-frequency (ultrasonication) at removing scale and rust from pipe sections and tubing. Use of a finned horn instead of a smooth horn improves energy dispersal and increases the efficiency of removal. The chemical data confirmed that rust and scale were removed from the pipe. The sonication technology showed significant potential and technical maturity to warrant a field test. The underwater plasma technology showed a potential for more effective scale and rust removal than the sonication technology. Chemical data from these tests also confirmed the removal of rust and scale from pipe sections and tubing. Focusing of the underwater plasma's energy field through the design and fabrication of a parabolic shield will increase the technology's efficiency. Power delivered to the underwater plasma unit by a sparkplug repeatedly was interrupted by sparkplug failure. The lifecycle for the plugs was less than 10 hours. An electrode feed system for delivering continuous power needs to be designed and developed. As a result, further work on the underwater plasma technology was terminated. It needs development of a new sparking system and a redesign of the pulsed power supply system to enable the unit to operate within a well diameter of less than three inches. Both of these needs were beyond the scope of the project. Meanwhile, the laboratory sonication unit was waterproofed and hardened, enabling the unit to be used as a field prototype, operating at temperatures to 350 F and depths of 15,000 feet. The field prototype was extensively tested at a field service company's test facility before taking it to the field site. The field test was run in August 2001 in a Nicor Gas storage field observation well at Pontiac, Illinois. Segmented bond logs, gamma ray neutron logs, water level measurements and water chemistry samples were obtained before and after the downhole demonstration. Fifteen tests were completed in the field. Results from the water chemistry analysis showed an increase in the range of calcium from 1755-1984 mg/l before testing to 3400-4028 mg/l after testing. For magnesium, the range increased from 285-296 mg/l to 461-480 mg/l. The change in pH from a range of 3.11-3.25 to 8.23-8.45 indicated a buffering of the acidic well water, probably due to the increased calcium available for buffering. The segmented bond logs showed no damage to the cement bond in the well and the gamma ray neutron log showed no increase in the amount of hydrocarbons present in the formation where the testing took place. Thus, the gas storage bubble in the aquifer was not compromised. A review of all the field test data collected documents the fact that the application of low-frequency sonication technology definitely removes scale from well pipe. Phase One of this project took sonication technology from the concept stage through a successful ''proof-of-concept'' downhole application in a natural gas storage field

James C. Furness; Donald O. Johnson; Michael L. Wilkey; Lynn Furness; Keith Vanderlee; P. David Paulsen

2001-12-01T23:59:59.000Z

420

Statistical Estimates For Channel Flows Driven By A Pressure Gradient  

E-Print Network [OSTI]

We present rigorous estimates for some physical quantities related to turbulent and non-turbulent channel flows driven by a uniform pressure gradient. Such results are based on the concept of stationary statistical solution, which is related to the notion of ensemble average for flows in statistical equilibrium. We provide a lower bound estimate for the mean skin friction coefficient and improve on a previous upper bound estimate for the same quantity; both estimates in terms of the Reynolds number. We also present lower and upper bound estimates for the mean rate of energy dissipation, the mean longitudinal velocity (in the direction of the pressure gradient), and the mean kinetic energy. In particular, we obtain an upper bound related to the energy dissipation law, namely that the mean rate of energy dissipation is essentially bounded by a non-dimensional universal constant times the cube of the mean longitudinal velocity over a characteristic macro-scale length. Finally, we investigate the scale-by-scale energy injection due to the pressure gradient, proving an upper bound estimate for the decrease of this energy injection as the scale length decreases.

Fabio Ramos; Ricardo Rosa; Roger Temam

2006-12-14T23:59:59.000Z

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Diffusion coefficient and radial gradient of galactic cosmic rays  

E-Print Network [OSTI]

We present the temporal changes of the diffusion coefficient K of galactic cosmic rays (GCRs) at the Earth orbit calculated based on the experimental data using two different methods. The first approach is based on the Parker convection-diffusion approximation of GCR modulation [1]: i.e. K~Vr=dI where dI is the variation of the GCR intensity measured by neutron monitors (NM),V is the solar wind velocity and r is the radial distance. The second approach is based on the interplanetary magnetic field (IMF) data. It was suggested that parallel mean free path can be expressed in terms of B as in [2]-[4]. Using data of the product of the parallel mean free path and radial gradient of GCR calculated based on the GCR anisotropy data (Ahluwalia et al., this conference ICRC 2013, poster ID: 487 [5]), we estimate the temporal changes of the radial gradient of GCR at the Earth orbit. We show that the radial gradient exhibits a strong solar cycle dependence (11-year variation) and a weak solar magnetic cycle dependence (2...

Modzelewska, Renata

2015-01-01T23:59:59.000Z

422

Neural networks predict well inflow performance  

E-Print Network [OSTI]

Predicting well inflow performance relationship accurately is very important for production engineers. From these predictions, future plans for handling and improving well performance can be established. One method of predicting well inflow...

Alrumah, Muhammad K.

2004-09-30T23:59:59.000Z

423

Industry survey for horizontal wells. Final report  

SciTech Connect (OSTI)

An international survey of horizontal environmental wells was performed during May and June of 1993. The purpose of the survey was to provide the environmental industry with an inventory of horizontal environmental wells and information pertaining to the extent of the use of horizontal environmental wells, the variety of horizontal environmental well applications, the types of geologic and hydrogeologic conditions within which horizontal environmental wells have been installed, and the companies that perform horizontal environmental well installations. Other information, such as the cost of horizontal environmental well installations and the results of tests performed on the wells, is not complete but is provided as general information with the caveat that the information should not be used to compare drilling companies. The result of the survey is a catalogue of horizontal environmental wells that are categorized by the objective or use of the wells, the vertical depth of the wells, and the drilling company contracted to install the wells.

Wilson, D.D.; Kaback, D.S. [CDM Federal Programs Corp., Denver, CO (United States); Denhan, M.E. [Westinghouse Savannah River Co., Aiken, SC (United States); Watkins, D. [CDM Federal Programs Corp., Aiken, SC (United States)

1993-07-01T23:59:59.000Z

424

New multilateral well architecture in heterogeneous reservoirs  

E-Print Network [OSTI]

. The performance of new multilateral well in heterogeneous reservoirs is studied, and that is compared with vertical well architecture also. In order to study the productivity of new multilateral wells, we use a numerical simulation method to set up heterogeneous...

Jia, Hongqiao

2004-09-30T23:59:59.000Z

425

INVITATIONAL WELL-TESTING SYMPOSIUM PROCEEDINGS  

E-Print Network [OSTI]

Oil, Gas, • . . 81 and Geothermal Well Tests (abstract) W.has been testing geothermal wells for about three years, andof Oil, Gas, and Geothermal Well Tests W. E. Brigham

Authors, Various

2011-01-01T23:59:59.000Z

426

Oil and Gas Wells: Regulatory Provisions (Kansas)  

Broader source: Energy.gov [DOE]

It shall be unlawful for any person, firm or corporation having possession or control of any natural gas well, oil well or coalbed natural gas well, whether as a contractor, owner, lessee, agent or...

427

Hottest spot temperatures in ventilated dry type transformers  

SciTech Connect (OSTI)

The hottest spot temperature allowance to be used for the different insulation system temperature classes is a major unknown facing IEEE Working Groups developing standards and loading guides for ventilated dry type transformers. In 1944, the hottest spot temperature allowance for ventilated dry type transformers was established as 30 C for 80 C average winding temperature rise. Since 1944, insulation temperature classes have increased to 220 C but IEEE standards continue to use a constant 30 C hottest spot temperature allowance. IEC standards use a variable hottest spot temperature allowance from 5 to 30 C. Six full size test windings were manufactured with imbedded thermocouples and 133 test runs performed to obtain temperature rise data. The test data indicated that the hottest spot temperature allowance used in IEEE standards for ventilated dry type transformers above 500 kVA is too low. This is due to the large thermal gradient from the bottom to the top of the windings caused by natural convection air flow through the cooling ducts. A constant ratio of hottest spot winding temperature rise to average winding temperature rise should be used in product standards for all insulation temperature classes. A ratio of 1.5 is suggested for ventilated dry type transformers above 500 kVA. This would increase the hottest spot temperature allowance from 30 C to 60 C and decrease the permissible average winding temperature rise from 150 C to 120 C for the 220 C insulation temperature class.

Pierce, L.W. (General Electric Co., Rome, GA (United States))

1994-01-01T23:59:59.000Z

428

Capping of Water Wells for Future Use  

E-Print Network [OSTI]

in determining the condition of your well, contact: S your local groundwater conservation dis- trict http://www.tceq.state.tx.us/permitting/ water_supply/groundwater/districts.html S a licensed water well driller in your area S the Water Well Drillers Program... are the steps in capping a well? The landowner, a licensed well driller or a licensed pump installer may cap a well. There are several steps involved. The well casing should extend above the ground surface to limit the risk of water entering the well...

Lesikar, Bruce J.; Mechell, Justin

2007-09-04T23:59:59.000Z

429

Fluid-Rock Characterization and Interactions in NMR Well Logging  

SciTech Connect (OSTI)

The objective of this project is to characterize the fluid properties and fluid-rock interactions that are needed for formation evaluation by NMR well logging. This is the first annual progress report submitted to the DOE. It reports on the work completed during the reporting period even if it may have started before this period. This project is a partnership between Professor George J. Hirasaki at Rice University and Professor Kishore Mohanty at University of Houston. In addition to the DOE, this project is supported by a consortium of oil companies and service companies. The fluid properties characterization has emphasized the departure of live oils from correlations based on dead oils. Also, asphaltic components can result in a difference between the T1 and T2 relaxation time distributions as well as reduce the hydrogen index. The fluid rock characterizations that are reported here are the effects of wettability and internal magnetic field gradients. A pore reconstruction method ha s been developed to recreate three-dimensional porous media from two-dimensional images that reproduce some of their key statistical properties. A Monte Carlo simulation technique has been developed to calculate the magnetization decay in fluid saturated porous media given their pore structure.

Hirasaki, George J.; Mohanty, Kishore, K.

2001-07-13T23:59:59.000Z

430

RAL-TR-2002-034 A Stopping Criterion for the Conjugate Gradient Algorithm in  

E-Print Network [OSTI]

Method Framework Mario Arioli 1 ABSTRACT The Conjugate Gradient method has always been successfully used for the conjugate gradient method 5 4 Numerical experiments 10 4.1 L-shape test problems stopping criterion for the conjugate gradient algorithm. The #12;nite element method approximates the weak

Mihajlovic, Milan D.

431

Ilya Lashuk and Andrew Knyazev 1 Steepest descent and conjugate gradient methods  

E-Print Network [OSTI]

Ilya Lashuk and Andrew Knyazev 1 Steepest descent and conjugate gradient methods with variable Mountain Conference 2006 Steepest descent and conjugate gradient methods with variable preconditioning #12 Steepest descent and conjugate gradient methods with variable preconditioning #12;Ilya Lashuk and Andrew

Knyazev, Andrew

432

A Set of Conjugate Gradient Routines for Real and Complex Arithmetics  

E-Print Network [OSTI]

The Conjugate Gradient method was proposed in different versions in the early 50s in separate contributionsA Set of Conjugate Gradient Routines for Real and Complex Arithmetics Val´erie Frayss´e Luc Giraud of the preconditioned conjugate gradient (CG) algorithm for both real and complex, single and double precision

433

Preconditioned conjugate gradient method for the sparse generalized eigenvalue problem in electronic structure  

E-Print Network [OSTI]

Preconditioned conjugate gradient method for the sparse generalized eigenvalue problem based on the conjugate gradient method is presented. The method is applied to first­principles elec problem, cast into variational form, is solved by the conjugate gradient method without first transforming

Haynes, Peter

434

Performance and Scalability of Preconditioned Conjugate Gradient Methods on Parallel Computers \\Lambda  

E-Print Network [OSTI]

Performance and Scalability of Preconditioned Conjugate Gradient Methods on Parallel Computers­scale parallel computers, iterative methods such as the Conjugate Gradient method for solving such systems of an iteration of the Preconditioned Conjugate Gradient Algorithm on parallel architectures with a variety

Kumar, Vipin

435

A Set of Conjugate Gradient Routines for Real and Complex Arithmetics  

E-Print Network [OSTI]

systems, Krylov methods, CG, reverse communication, distributed mem­ ory. 1 The Conjugate Gradient algorithm 1.1 General description The Conjugate Gradient method was proposed in di#erent versions with the symmetric Lanczos matrix There is a close relationship between the conjugate gradient method and the Lanczos

436

Solving a Two-Dimensional Elliptic Model Problem with the Conjugate Gradient Method Using  

E-Print Network [OSTI]

Solving a Two-Dimensional Elliptic Model Problem with the Conjugate Gradient Method Using Matrix Preconditioned Conjugate Gradient method in Matlab can be optimized in terms of wall clock time and, more-free Preconditioned Conjugate Gradient method. This superior algorithm computes the same numerical solution to our

Gobbert, Matthias K.

437

Conjugate gradient method for dual-dual mixed formulations Gabriel N. Gatica y Norbert Heuer z  

E-Print Network [OSTI]

Conjugate gradient method for dual-dual mixed formulations #3; Gabriel N. Gatica y Norbert Heuer z, the conjugate gradient method with this special inner product can be used as iterative solver. For a model-dual variational formulation, conjugate gradient method. Mathematics subject classi#12;cations (1991). 65N30, 65N22

Heuer, Norbert

438

Convergence of Three-term Conjugate Gradient Methods Y. H. Dai and Y. Yuan  

E-Print Network [OSTI]

Convergence of Three-term Conjugate Gradient Methods Y. H. Dai and Y. Yuan State Key Laboratory@lsec.cc.ac.cn, yyx@lsec.cc.ac.cn Abstract This paper studies the three-term conjugate gradient method for unconstrained opti- mization. The method includes the classical (two-term) conjugate gradient method

Yuan, Ya-xiang

439

Time Complexity of a Parallel Conjugate Gradient Solver for Light Scattering Simulations  

E-Print Network [OSTI]

parallelization for distributed memory computers of a preconditioned Conjugate Gradient method, applied to solve of the Conjugate Gradient method is analyzed theoretically. First expressions for the execution time for three, preconditioned conjugate gradient method, data decomposition, time complexity analysis, performance measurement

Hoffmann, Walter

440

A fast GPU Implementation of the Deflated Preconditioned Conjugate Gradient method  

E-Print Network [OSTI]

A fast GPU Implementation of the Deflated Preconditioned Conjugate Gradient method List of authors to the fastest method: DIPCG2. · (CGVV) Conjugate Gradient - Vanilla Version, · (CGBIC) Conjugate Gradient Preconditioned Conjugate Gra- dient Method. Most of the important building blocks of this algorithm could

Boyer, Edmond

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

The Role of the Inner Product in Stopping Criteria for Conjugate Gradient Iterations  

E-Print Network [OSTI]

stopping criteria are derived for conjugate gradient (CG) methods, based on iteration parameters criteria, conjugate gradient methods, B-normal matrices 1 Introduction Unlike a direct method, an iterative1 The Role of the Inner Product in Stopping Criteria for Conjugate Gradient Iterations S. F. Ashby

Holst, Michael J.

442

Implementation of a parallel conjugate gradient method for simulation of elastic light scattering  

E-Print Network [OSTI]

1 Implementation of a parallel conjugate gradient method for simulation of elastic light scattering solved with (preconditioned) conjugate gradient methods. For realistic problems the size of the matrix gradient method for this type of problems, with emphasis on coarse grain distributed memory implementations

443

Copyright information to be inserted by the Publishers ANALYSIS ON THE CONJUGATE GRADIENT  

E-Print Network [OSTI]

Copyright information to be inserted by the Publishers ANALYSIS ON THE CONJUGATE GRADIENT METHOD YA 17 January 1993) In this paper we analyze the conjugate gradient method when the objective function is quadratic. We apply backward analyses to study the quadratic termination of the conjugate gradient method

Yuan, Ya-xiang

444

Exploiting hyper-sparsity when computing preconditioners for conjugate gradients in interior point methods  

E-Print Network [OSTI]

for conjugate gradients in interior point methods 1 #12;Hyper-sparsity in operations with B-1 Represent B-1 computing preconditioners for conjugate gradients in interior point methods 3 #12;Interior point methods computing preconditioners for conjugate gradients in interior point methods 4 #12;Design

Hall, Julian

445

Algorithm PREQN: Fortran 77 Subroutines for Preconditioning the Conjugate Gradient Method  

E-Print Network [OSTI]

Algorithm PREQN: Fortran 77 Subroutines for Preconditioning the Conjugate Gradient Method Jos subroutines for automatically generating pre­ conditioners for the conjugate gradient method. It is designed the conjugate gradient method. They are designed for solving a sequence of linear systems, A i x = b i ; i = 1

Nocedal, Jorge

446

A conjugate-gradient based approach for approximate solutions of quadratic programs  

E-Print Network [OSTI]

on the two-norm of the columns, the method is equivalent to the conjugate-gradient method. Further, the above, the numerical results demonstrate that, like the conjugate-gradient method, a rapid decrease of the objective. column generation, conjugate-gradient method, intensity-modulated radiation therapy, step

Forsgren, Anders

447

3D Shape from Silhouette Points in Registered 2D Images Using Conjugate Gradient Method  

E-Print Network [OSTI]

3D Shape from Silhouette Points in Registered 2D Images Using Conjugate Gradient Method Andrzej version of the conjugate gradient method. We take advantage of the structure of the problem to make polynomial function. The approximate problem is solved using a nonlinear conjugate gradient solver that takes

Hoff, William A.

448

Algorithm PREQN: Fortran 77 Subroutines for Preconditioning the Conjugate Gradient Method  

E-Print Network [OSTI]

Algorithm PREQN: Fortran 77 Subroutines for Preconditioning the Conjugate Gradient Method Jose Luis for automatically generating pre- conditioners for the conjugate gradient method. It is designed for solving: Preconditioning, conjugate gradient method, quasi- Newton method, Hessian-free Newton method, limited memory

Nocedal, Jorge

449

PRECONDITIONED CONJUGATE GRADIENT METHODS FOR THE INCOMPRESSIBLE NAVIER-STOKES EQUATIONS  

E-Print Network [OSTI]

PRECONDITIONED CONJUGATE GRADIENT METHODS FOR THE INCOMPRESSIBLE NAVIER-STOKES EQUATIONS P. CHIN of using a conjugate gradient type method with an incomplete LU factorization preconditioner for two is to use an iterative matrix method. Recently, several authors have applied conjugate gradient type methods

Waterloo, University of

450

Parallelizable Preconditioned Conjugate Gradient Methods for the Cray Y-MP and the TMC CM-2  

E-Print Network [OSTI]

Parallelizable Preconditioned Conjugate Gradient Methods for the Cray Y-MP and the TMC CM-2 William preconditioned conjugate gradient methods to the numerical solution of the diffusion equation governing the flow provides a comparison of the performance characteristics of several preconditioned conjugate gradient (PCG

Navon, Michael

451

A MULTI-PRECONDITIONED CONJUGATE GRADIENT ROBERT BRIDSON AND CHEN GREIF  

E-Print Network [OSTI]

propose a generalization of the conjugate gradient method that uses multiple preconditioners, combining and differences with the standard and block conjugate gradient methods. Numerical examples illustrate and validate, preconditioning, Krylov subspace solvers 1. Introduction. The conjugate gradient (CG) method is celebrating its 53

Bridson, Robert

452

A SURVEY OF NONLINEAR CONJUGATE GRADIENT METHODS WILLIAM W. HAGER AND HONGCHAO ZHANG  

E-Print Network [OSTI]

A SURVEY OF NONLINEAR CONJUGATE GRADIENT METHODS WILLIAM W. HAGER AND HONGCHAO ZHANG Abstract. This paper reviews the development of different versions of nonlinear conjugate gradient methods, with special attention given to global convergence properties. Key words. Nonlinear conjugate gradient methods

Zhang, Hongchao

453

ON THE BEHAVIOR OF THE CONJUGATE-GRADIENT METHOD ON ILL-CONDITIONED PROBLEMS  

E-Print Network [OSTI]

ON THE BEHAVIOR OF THE CONJUGATE-GRADIENT METHOD ON ILL-CONDITIONED PROBLEMS Anders FORSGREN Abstract We study the behavior of the conjugate-gradient method for solving a set of linear equations. conjugate-gradient method, symmetric positive-definite ma- trix, ill-conditioning AMS subject

Forsgren, Anders

454

On the Relation Between Steep Monoclinal Flexure Zones and Steep Hydraulic Gradients  

E-Print Network [OSTI]

On the Relation Between Steep Monoclinal Flexure Zones and Steep Hydraulic Gradients by Y. Yechieli1, U. Kafri2, S. Wollman2, V. Lyakhovsky2, and R. Weinberger2 Abstract Steep hydraulic gradients of the hydraulic conductivity, which is responsible for the steep gradients, has seldom been studied. We present

Lyakhovsky, Vladimir

455

Adaptive Restart for Accelerated Gradient Schemes Brendan O'Donoghue Emmanuel Cand`es  

E-Print Network [OSTI]

Adaptive Restart for Accelerated Gradient Schemes Brendan O'Donoghue Emmanuel Cand`es April 13- matically improve the convergence rate of accelerated gradient schemes. The analysis of the technique relies. In what we refer to as the `high momentum' regime the iterates generated by an accelerated gradient scheme

Candes, Emmanuel J.

456

Helicopter magnetic survey conducted to locate wells  

SciTech Connect (OSTI)

A helicopter magnetic survey was conducted in August 2007 over 15.6 sq mi at the Naval Petroleum Reserve No. 3’s (NPR-3) Teapot Dome Field near Casper, Wyoming. The survey’s purpose was to accurately locate wells drilled there during more than 90 years of continuous oilfield operation. The survey was conducted at low altitude and with closely spaced flight lines to improve the detection of wells with weak magnetic response and to increase the resolution of closely spaced wells. The survey was in preparation for a planned CO2 flood for EOR, which requires a complete well inventory with accurate locations for all existing wells. The magnetic survey was intended to locate wells missing from the well database and to provide accurate locations for all wells. The ability of the helicopter magnetic survey to accurately locate wells was accomplished by comparing airborne well picks with well locations from an intense ground search of a small test area.

Veloski, G.A.; Hammack, R.W.; Stamp, V. (Rocky Mountain Oilfield Testing Center); Hall, R. (Rocky Mountain Oilfield Testing Center); Colina, K. (Rocky Mountain Oilfield Testing Center)

2008-07-01T23:59:59.000Z

457

Case histories of temperature surveys in Kuwait  

SciTech Connect (OSTI)

Most crude produced in Kuwait is from naturally flowing wells. Casing, tubing, and cement in these wells remain unchanged after completion. This study discusses the major application of temperature surveys in indicating fluid movement both inside and behind the production string, hence locating any holes in the casing. Some significant cases of temperature anomalies are examined qualitatively, and suggestions are made for a more quantitative interpretation of temperature profiles. 9 refs.

Gupta, B.S.

1981-12-01T23:59:59.000Z

458

High Temperatures & Electricity Demand  

E-Print Network [OSTI]

High Temperatures & Electricity Demand An Assessment of Supply Adequacy in California Trends.......................................................................................................1 HIGH TEMPERATURES AND ELECTRICITY DEMAND.....................................................................................................................7 SECTION I: HIGH TEMPERATURES AND ELECTRICITY DEMAND ..........................9 BACKGROUND

459

Track 4: Employee Health and Wellness  

Broader source: Energy.gov [DOE]

ISM Workshop Presentations Knoxville Convention Center, Knoxville, TN August 2009 Track 4: Employee Health and Wellness

460

Thank you for joining: 360WELLNESS  

E-Print Network [OSTI]

shortly. If you are experiencing technical difficulties with Adobe Connect, please call 1 March 22, 2012 12 pm ­ 1pm ET #12;360° WELLNESS: Achieving Wellness At Work And At Home Workshop & Self-Assessment © Joe Rosenlicht, Certified Coach 3 #12;8 Wellness Areas Wellness Nutrition Brain Power Fitness Sleep

Vertes, Akos

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Nanoparticle characterization by continuous contrast variation in SAXS with a solvent density gradient  

E-Print Network [OSTI]

Many low-density nanoparticles show a radial inner structure. This work proposes a novel approach to contrast variation with SAXS based on the constitution of a solvent density gradient in a glass capillary in order to resolve this internal morphology. Scattering curves of a polymeric core-shell colloid were recorded at different suspending medium contrasts at the four-crystal monochromator beamline of PTB at the synchrotron radiation facility BESSY II. The mean size and size distribution of the particles as well as an insight into the colloid electron density composition were determined using the position of the isoscattering points in the Fourier region of the scattering curves and by examining the Guinier region in detail. These results were corroborated with a model fit to the experimental data, which provided complementary information about the inner electron density distribution of the suspended nanoparticles.

Raul Garcia-Diez; Christian Gollwitzer; Michael Krumrey

2014-10-27T23:59:59.000Z

462

Multi-temperature representation of electron velocity distribution functions. I. Fits to numerical results  

SciTech Connect (OSTI)

Electron energy distribution functions are expressed as a sum of 6-12 Maxwellians or a sum of 3, but each multiplied by a finite series of generalized Laguerre polynomials. We fitted several distribution functions obtained from the finite difference Fokker-Planck code 'FPI'[Matte and Virmont, Phys. Rev. Lett. 49, 1936 (1982)] to these forms, by matching the moments, and showed that they can represent very well the coexistence of hot and cold populations, with a temperature ratio as high as 1000. This was performed for two types of problems: (1) the collisional relaxation of a minority hot component in a uniform plasma and (2) electron heat flow down steep temperature gradients, from a hot to a much colder plasma. We find that the multi-Maxwellian representation is particularly good if we accept complex temperatures and coefficients, and it is always better than the representation with generalized Laguerre polynomials for an equal number of moments. For the electron heat flow problem, the method was modified to also fit the first order anisotropy f{sub 1}(x,v,t), again with excellent results. We conclude that this multi-Maxwellian representation can provide a viable alternative to the finite difference speed or energy grid in kinetic codes.

Haji Abolhassani, A. A.; Matte, J.-P. [INRS-Energie, Materiaux et Telecommunications, Universite du Quebec, Varennes, Quebec J3X 1S2 (Canada)

2012-10-15T23:59:59.000Z

463

Deep Geothermal Reservoir Temperatures in the Eastern Snake River Plain, Idaho using Multicomponent Geothermometry  

SciTech Connect (OSTI)

The U.S. Geological survey has estimated that there are up to 4,900 MWe of undiscovered geothermal resources and 92,000 MWe of enhanced geothermal potential within the state of Idaho. Of particular interest are the resources of the Eastern Snake River Plain (ESRP) which was formed by volcanic activity associated with the relative movement of the Yellowstone Hot Spot across the state of Idaho. This region is characterized by a high geothermal gradient and thermal springs occurring along the margins of the ESRP. Masking much of the deep thermal potential of the ESRP is a regionally extensive and productive cold-water aquifer. We have undertaken a study to infer the temperature of the geothermal system hidden beneath the cold-water aquifer of the ESRP. Our approach is to estimate reservoir temperatures from measured water compositions using an inverse modeling technique (RTEst) that calculates the temperature at which multiple minerals are simultaneously at equilibrium while explicitly accounting for the possible loss of volatile constituents (e.g., CO2), boiling and/or water mixing. In the initial stages of this study, we apply the RTEst model to water compositions measured from a limited number of wells and thermal springs to estimate the regionally extensive geothermal system in the ESRP.

Ghanashyam Neupane; Earl D. Mattson; Travis L. McLing; Carl D. Palmer; Robert W. Smith; Thomas R. Wood

2014-02-01T23:59:59.000Z

464

New well control companies stress planning, engineering  

SciTech Connect (OSTI)

The technology for capping a blowing well has not changed during the last 50 years. Still, operators are finding new ways of using well control companies' expertise to help avoid potentially disastrous situations. This trend is especially critical given the current environmentally sensitive and cost-cutting times facing the oil industry. While regulatory agencies world-wide continue to hinder well control efforts during an offshore event, well control companies are focusing on technologies to make their job easier. Some of the most exciting are the hydraulic jet cutter, which gained fame in Kuwait, and electromagnetic ranging for drilling more accurate relief wells. With the number of subsea wells increasing, subsea intervention is a major target for future innovations. Well control companies are experiencing a change in their role to the offshore oil industry. Well control professionals discuss this expanded responsibility as well as other aspects of offshore blowouts including regulatory hindrances, subsea intervention and future technologies.

Bell, S.; Wright, R.

1994-04-01T23:59:59.000Z

465

Vapor port and groundwater sampling well  

DOE Patents [OSTI]

A method and apparatus has been developed for combining groundwater monitoring wells with unsaturated-zone vapor sampling ports. The apparatus allows concurrent monitoring of both the unsaturated and the saturated zone from the same well at contaminated areas. The innovative well design allows for concurrent sampling of groundwater and volatile organic compounds (VOCs) in the vadose (unsaturated) zone from a single well, saving considerable time and money. The sample tubes are banded to the outer well casing during installation of the well casing.

Hubbell, Joel M. (Idaho Falls, ID); Wylie, Allan H. (Idaho Falls, ID)

1996-01-01T23:59:59.000Z

466

Vapor port and groundwater sampling well  

DOE Patents [OSTI]

A method and apparatus have been developed for combining groundwater monitoring wells with unsaturated-zone vapor sampling ports. The apparatus allows concurrent monitoring of both the unsaturated and the saturated zone from the same well at contaminated areas. The innovative well design allows for concurrent sampling of groundwater and volatile organic compounds (VOCs) in the vadose (unsaturated) zone from a single well, saving considerable time and money. The sample tubes are banded to the outer well casing during installation of the well casing. 10 figs.

Hubbell, J.M.; Wylie, A.H.

1996-01-09T23:59:59.000Z

467

High and ulta-high gradient quadrupole magnets  

SciTech Connect (OSTI)

Small bore conventional dc quadrupoles with apertures from 1 to 2.578cm were designed and prototypes built and measured. New fabrication techniques including the use of wire electric discharge milling (EDM) to economically generate the pole tip contours and aperture tolerances are described. Magnetic measurement data from a prototype of a 1cm aperture quadrupole with possible use in future e/sup +//e/sup -/ super colliders are presented. At a current of 400A, the lens achieved a gradient of 2.475 T/cm, and had an efficiency of 76.6%.

Brunk, W.O.; Walz, D.R.

1985-05-01T23:59:59.000Z

468

Fabrication of high gradient insulators by stack compression  

DOE Patents [OSTI]

Individual layers of a high gradient insulator (HGI) are first pre-cut to their final dimensions. The pre-cut layers are then stacked to form an assembly that is subsequently pressed into an HGI unit with the desired dimension. The individual layers are stacked, and alignment is maintained, using a sacrificial alignment tube that is removed after the stack is hot pressed. The HGI's are used as high voltage vacuum insulators in energy storage and transmission structures or devices, e.g. in particle accelerators and pulsed power systems.

Harris, John Richardson; Sanders, Dave; Hawkins, Steven Anthony; Norona, Marcelo

2014-04-29T23:59:59.000Z

469

Superconducting travelling wave ring with high gradient accelerating section  

SciTech Connect (OSTI)

Use of a superconducting traveling wave accelerating (STWA) structure instead of a standing wave cavity has major advantages in increasing the accelerating gradient in the ILC. In contrast with standing wave cavity STWA requires feedback loop, which sends wave from the structure output to input, making a superconducting traveling wave ring (STWR). One or few input couplers need to excite STWR and compensate power dissipations due to beam loading. To control traveling wave regime in the structure two independent knobs can be used for tuning both resonant ring frequency and backward wave. We discuss two variants of the STWR with one and two feed couplers.

Avrakhov, P.; Solyak, N.; /Fermilab

2007-06-01T23:59:59.000Z

470

Gradient index liquid crystal devices and method of fabrication thereof  

DOE Patents [OSTI]

Laser beam apodizers using cholesteric liquid crystals provides soft edge profile by use of two separate cholesteric liquid crystal mixtures with different selective reflection bands which in an overlap region have a gradient index where reflectivity changes as a function of position. The apodizers can be configured as a one-dimensional beam apod INTRODUCTION The U.S. government has rights in the invention under Contract No. DE-FC03-85DP40200 between the University of Rochester and the Department of Energy.

Lee, J.C.; Jacobs, S.

1991-10-29T23:59:59.000Z

471

High Gradient Inverse Free Electron Laser (IFEL) Accelerator  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-SeriesFlickr FlickrGuidedCH2M HILLAdministration | National|Gradient High

472

Well performance graph simplifies field calculations  

SciTech Connect (OSTI)

Graphic Methods are widely employed in order to understand overall well behavior using only surface parameters. The authors propose a new graphic method, used successfully by Agip for oil and gas wells in Italy, Libya, Nigeria and Tunisia. The well performance graph helps solve many production problems, including estimation of: inflow performance relationship; causes of rate decline throughout well life; and production rate and bottomhole flowing pressure for various pressures upstream of the surface choke, and vice-versa. This method differs from others by using flow behavior through the choke for both critical and subcritical conditions. Equations describing flow through the formation, string and surface choke are also used. Results are quite reliable when these theoretical equations are calibrated with field data, either from the well concerned or from nearby wells producing the same fluid. This article describes the technique as it applies to oil wells. The methodology for gas wells is similar.

De Ghetto, G.

1987-05-01T23:59:59.000Z

473

RFI Well Integrity 06 JUL 1400  

Broader source: Energy.gov [DOE]

This PowerPoint report entitled "Well Integrity During Shut - In Operations: DOE/DOI Analyses" describes risks and suggests risk management recommendations associated with shutting in the well.

474

Economic evaluation of smart well technology  

E-Print Network [OSTI]

comprehensive review of this technology has been discussed. The possible reservoir environments in which smart well technology could be used and also, the possible benefits that could be realized by utilizing smart well technology has been discussed...

Al Omair, Abdullatif A.

2007-09-17T23:59:59.000Z

475

Disinfecting Water Wells by Shock Chlorination  

E-Print Network [OSTI]

If your well has been flooded, it must be shock chlorinated before it can be used as a source of drinking water. This publication explains how to disinfect a well using either dry chlorine or liquid household bleach....

Dozier, Monty; McFarland, Mark L.

2005-09-30T23:59:59.000Z

476

INVITATIONAL WELL-TESTING SYMPOSIUM PROCEEDINGS  

E-Print Network [OSTI]

Discharge Using Ground- Water Storage," Trans. , AGU (1935),of a well using ground-water storage: ~n. Geophys. Unionof a Well Using Ground-Water Storage," Trans. , AGU (1935),

Authors, Various

2011-01-01T23:59:59.000Z

477

Well Owner's Guide To Water Supply  

E-Print Network [OSTI]

's groundwater and guidelines, including national drinking water standards, to test well water to insure safe drinking water in private wells. National drinking water standards and common methods of home water .....................22 Contaminants in Water........................................23 Drinking Water Guidelines

Fay, Noah

478

Production Trends of Shale Gas Wells  

E-Print Network [OSTI]

To obtain better well performance and improved production from shale gas reservoirs, it is important to understand the behavior of shale gas wells and to identify different flow regions in them over a period of time. It is also important...

Khan, Waqar A.

2010-01-14T23:59:59.000Z

479

Completion Report for Well ER-20-4 Corrective Action Units 101 and 102: Central and Western Pahute Mesa  

SciTech Connect (OSTI)

Well ER-20-4 was drilled for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office in support of the Nevada Environmental Restoration Project at the Nevada National Security Site, Nye County, Nevada. The well was drilled in August and September 2010 as part of the Pahute Mesa Phase II drilling program. The primary purpose of the well was to investigate the possibility of radionuclide transport from up-gradient underground nuclear tests conducted in central Pahute Mesa. This well also provided detailed hydrogeologic information in the Tertiary volcanic section that will help reduce uncertainties within the Pahute Mesa-Oasis Valley hydrostratigraphic framework model.

NSTec Environmental Management

2011-04-30T23:59:59.000Z

480

Exploring the effect of Al2O3 ALD coating on a high gradient ILC single-cell cavity  

SciTech Connect (OSTI)

Encouraged by work at Argonne National Lab, we investigated atomic layer deposition technique (ALD) for high gradient superconducting RF cavities at JLab with an ALD coating system of Old Dominion University located on the JLab site. The goal of this study was to look into the possibility of coating a dielectric layer on top of RF niobium surface at a lower temperature of 120 C as compared to ANL coatings at 200 C to preserve niobium pentoxide on niobium surface. The initial coatings showed complete, but non-uniform coatings of the surface with several areas exhibiting discoloration, which was probably due to the temperature variation across the cavity surface. The initial coating showed a high RF losses, which were improved after discolored areas on the beam tubes were removed with HF rinse of the beam tubes only. The best result was 2 109 low field Q0 and Eacc = 18 MV/m limited by available power.

Grigory Eremeev, Anne-Marie Valente, Andy Wu, Diefeng Gu

2012-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "temperature gradient wells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Opacity and gradients in aluminum wire array z-pinch implosions on the Z pulsed power facility  

SciTech Connect (OSTI)

Aluminum wire array z pinches imploded on the Z generator are an extremely bright source of 1–2?keV radiation, with close to 400?kJ radiated at photon energies >1?keV and more than 50?kJ radiated in a single line (Al Ly-?). Opacity plays a critical role in the dynamics and K-shell radiation efficiency of these pinches. Where significant structure is present in the stagnated pinch this acts to reduce the effective opacity of the system as demonstrated by direct analysis of spectra. Analysis of time-integrated broadband spectra (0.8–25?keV) indicates electron temperatures ranging from a few 100?eV to a few keV are present, indicative of substantial temperature gradients.

Ampleford, D. J., E-mail: damplef@sandia.gov; Hansen, S. B.; Jennings, C. A.; Jones, B.; Coverdale, C. A.; Harvey-Thompson, A. J.; Rochau, G. A.; Dunham, G.; Moore, N. W.; Harding, E. C.; Cuneo, M. E. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States); Chong, Y.-K.; Clark, R. W.; Ouart, N.; Thornhill, J. W.; Giuliani, J.; Apruzese, J. P. [Naval Research Laboratory, Washington, DC 20375 (United States)] [Naval Research Laboratory, Washington, DC 20375 (United States)

2014-03-15T23:59:59.000Z

482

Geology and Geothermal Potential North of Wells, Nevada  

SciTech Connect (OSTI)

The geology north of Wells, Nevada is dominated by approximately 2150 m of Tertiary lacustrine siltstones and conglomerates. The sediments are cut by a high-angle, range-bounding fault and several associated step faults. Hydrothermal alteration and silicification are associated with the high-angle faults. Two ages of Quaternary sediments locally overlie the Tertiary sediments. Lithologic and well log analyses define numerous potential aquifers in the Tertiary sediments. The shallowest of these aquifers is overlain by a tuffaceous siltstone which appears to act as an aquitard for hot water moving through the aquifers. Three possible subsurface hydrologic models can be constructed to explain the spatial relationships of the thermal water near Wells. Cost-effective steps taken to expedite geothermal development in the area might include deepening of an existing domestic well in the city of Wells to at least 180 m in order to penetrate the tuffaceous siltstone aquitard, running borehole logs for all existing wells, and conducting a shallow temperature-probe survey in the Tertiary sediments north of Wells.

Jewell, Paul W.

1982-11-01T23:59:59.000Z

483

Ultra-High Gradient Dielectric Wakefield Accelerator Experiments  

SciTech Connect (OSTI)

Ultra-high gradient dielectric wakefield accelerators are a potential option for a linear collider afterburner since they are immune to the ion collapse and electron/positron asymmetry problems implicit in a plasma based afterburner. The first phase of an experiment to study the performance of dielectric Cerenkov wakefield accelerating structures at extremely high gradients in the GV/m range has been completed. The experiment took advantage of the unique SLAC FFTB electron beam and its ultra-short pulse lengths and high currents (e.g., {sigma}{sub z} = 20 {micro}m at Q = 3 nC). The FFTB electron beam was successfully focused down and sent through short lengths of fused silica capillary tubing (ID = 200 {micro}m/OD = 325 {micro}m). The pulse length of the electron beam was varied to produce a range of electric fields between 2 and 20 GV/m at the inner surface of the dielectric tubes. We observed a sharp increase in optical emissions from the capillaries in the middle part of this surface field range which we believe indicates the transition between sustainable field levels and breakdown. If this initial interpretation is correct, the surfaced fields that were sustained equate to on axis accelerating field of several GV/m. In future experiments being developed for the SLAC SABER and BNL ATF we plan to use the coherent Cerenkov radiation emitted from the capillary tube as a field strength diagnostic and demonstrate GV/m range particle energy gain.

Thompson, M C; Badakov, H; Rosenzweig, J B; Travish, G; Hogan, M; Ischebeck, R; Kirby, N; Siemann, R; Walz, D; Muggli, P; Scott, A; Yoder, R

2006-08-04T23:59:59.000Z

484

Ultra-High Gradient Dielectric Wakefield Accelerator Experiments  

SciTech Connect (OSTI)

Ultra-high gradient dielectric wakefield accelerators are a potential option for a linear collider afterburner since they are immune to the ion collapse and electron/positron asymmetry problems implicit in a plasma based afterburner. The first phase of an experiment to study the performance of dielectric Cerenkov wakefield accelerating structures at extremely high gradients in the GV/m range has been completed. The experiment took advantage of the unique SLAC FFTB electron beam and its ultra-short pulse lengths and high currents (e.g., {sigma}z = 20 {mu}m at Q = 3 nC). The FFTB electron beam was successfully focused down and sent through short lengths of fused silica capillary tubing (ID = 200 {mu}m / OD = 325 {mu}m). The pulse length of the electron beam was varied to produce a range of electric fields between 2 and 20 GV/m at the inner surface of the dielectric tubes. We observed a sharp increase in optical emissions from the capillaries in the middle part of this surface field range which we believe indicates the transition between sustainable field levels and breakdown. If this initial interpretation is correct, the surfaced fields that were sustained equate to on axis accelerating field of several GV/m. In future experiments being developed for the SLAC SABER and BNL ATF we plan to use the coherent Cerenkov radiation emitted from the capillary tube as a field strength diagnostic and demonstrate GV/m range particle energy gain.

Thompson, M. C. [Lawrence Livermore National Laboratory, Livermore, California, 90095 (United States); Badakov, H.; Rosenzweig, J. B.; Travis, G. [UCLA Department of Physics and Astronomy, Los Angeles, California, 90095 (United States); Hogan, M.; Ischebeck, R.; Kirby, N.; Siemann, R.; Walz, D. [Stanford Linear Accelerator Center, Stanford, California, 94309 (United States); Muggli, P. [University of Southern California Los Angeles, California, 90089 (United States); Scott, A. [UCSB Department of Physics, Santa Barbara, California, 93106 (United States); Yoder, R. [Manhattan College, Riverdale, New York, 10471 (United States)

2006-11-27T23:59:59.000Z

485

High temperature lightweight foamed cements  

DOE Patents [OSTI]

Cement slurries are disclosed which are suitable for use in geothermal wells since they can withstand high temperatures and high pressures. The formulation consists of cement, silica flour, water, a retarder, a foaming agent, a foam stabilizer, and a reinforcing agent. A process for producing these cements is also disclosed. 3 figs.

Sugama, Toshifumi.

1989-10-03T23:59:59.000Z

486

High temperature lightweight foamed cements  

DOE Patents [OSTI]

Cement slurries are disclosed which are suitable for use in geothermal wells since they can withstand high temperatures and high pressures. The formulation consists of cement, silica flour, water, a retarder, a foaming agent, a foam stabilizer, and a reinforcing agent. A process for producing these cements is also disclosed.

Sugama, Toshifumi (Mastic Beach, NY)

1989-01-01T23:59:59.000Z

487

Application of a Downhole Flowmeter to Detecting Casing Breaks in a Geothermal Well  

SciTech Connect (OSTI)

The downhole flowmeter logging system for high temperature geothermal wells developed at Wairakei, New Zealand, is proving to be an invaluable tool for use during workovers to repair or reinstate problem wells. This contribution describes a straightforward example of identifying breaks in plain casing near the top of a productive well.

Syms, Margot C.; Syms, Peter H.; Bixley, Paul F.

1980-12-16T23:59:59.000Z

488

Thermal extraction analysis of five Los Azufres production wells  

SciTech Connect (OSTI)

Thermal energy extraction from five wells supplying 5-MWe wellhead generators in three zones of the Los Azufres geothermal field has been examined from production and chemical data compiled over 14-years of operation. The data, as annual means, are useful in observing small-scale changes in reservoir performance with continuous production. The chemical components are chloride for quality control and the geothermometer elements for reservoir temperatures. The flowrate and fluid enthalpy data are used to calculate the thermal extraction rates. Integration of these data provides an estimate of the total energy extracted from the zone surrounding the well. The combined production and chemical geothermometer data are used to model the produced fluid as coming from just-penetrating wells for which the annual produced mass originates from a series of concentric hemispheric shells moving out into the reservoir. Estimates are made of the drawdown distance into the reservoir and the far-field conditions.

Kruger, Paul; Quijano, Luis

1995-01-26T23:59:59.000Z

489

Potential hydrologic characterization wells in Amargosa Valley  

SciTech Connect (OSTI)

More than 500 domestic, agricultural, and monitoring wells were identified in the Amargosa Valley. From this list, 80 wells were identified as potential hydrologic characterization wells, in support of the US Department of Energy (DOE) Underground Test Area/Remedial Investigation and Feasibility Study (UGTA/RIFS). Previous hydrogeologic studies have shown that groundwater flow in the basin is complex and that aquifers may have little lateral continuity. Wells located more than 10 km or so from the Nevada Test Site (NTS) boundary may yield data that are difficult to correlate to sources from the NTS. Also, monitoring well locations should be chosen within the guidelines of a hydrologic conceptual model and monitoring plan. Since these do not exist at this time, recompletion recommendations will be restricted to wells relatively close (approximately 20 km) to the NTS boundary. Recompletion recommendations were made for two abandoned agricultural irrigation wells near the town of Amargosa Valley (previously Lathrop Wells), for two abandoned wildcat oil wells about 10 km southwest of Amargosa Valley, and for Test Well 5 (TW-5), about 10 km east of Amargosa Valley.

Lyles, B.; Mihevc, T.

1994-09-01T23:59:59.000Z

490

Calculation of Auger rates in a quantum well structure and its application to InGaAsP quantum well lasers  

SciTech Connect (OSTI)

We discuss the possible intrinsic limitation on the temperature dependence of threshold current of long wavelength InGaAsP quantum well lasers caused by Auger recombination and intervalence band absorption. A model calculation of the various band-to-band Auger rates are presented. We find that the Auger rates increase with decreasing band gap and also with increasing temperature as in the case of bulk semiconductors. The temperature dependence and the band-gap dependence arises from the energy and momentum conservation (in the direction normal to the well) that the four particle states involved must satisfy. The estimated Auger coefficient is large enough to be important in single quantum well lasers. However, the Auger effect should be much smaller in a multiquantum well laser than for a single quantum well laser. This is because the carrier density at threshold is smaller (by a factor of 3 to 4) for multiquantum well lasers than for single quantum well lasers. The increased intervalence band absorption with increasing temperature in the active layer may not be responsible for increased threshold current of single quantum well lasers.

Dutta, N.K.

1983-03-01T23:59:59.000Z

491

Geopressured-geothermal well report. Volume I. Drilling and completion  

SciTech Connect (OSTI)

Gladys McCall site activities are covered through the completion of the test well and salt water disposal well. The test well was drilled to a total depth of 16,510 feet, then plugged back to 15,831 feet. Three 4'' diameter diamond cores were taken for analysis. An existing well on site, the Getty-Butts Gladys McCall No. 1, was reentered and completed to a depth of 3514 feet as a salt water disposal well. The geologic interpretation of the Gladys McCall site indicated target sands for testing at 15,080 feet through 15, 831 feet. Reservoir fluid temperature at this depth is estimated to be approximately 313/sup 0/F and pressure is estimated to be +-12,800 psi. The preliminary reservoir volume estimate is 3.6 billion barrels of brine. The design wells program includes environmental monitoring of the Gladys McCall site by Louisiana State University. Field stations are set up to monitor surface and ground water quality, subsidence, land loss and shoreline erosion, and seismicity. As of December 31, 1981 the study shows no significant impact on the environment by site operations.

Not Available

1982-01-01T23:59:59.000Z

492

ADVANCED TECHNOLOGIES FOR STRIPPER GAS WELL ENHANCEMENT  

SciTech Connect (OSTI)

As part of Task 1 in Advanced Technologies for Stripper Gas Well Enhancement, Schlumberger--Holditch Reservoir Technologies (H-RT) joined with two Appalachian Basin producers, Great Lakes Energy Partners, LLC, and Belden and Blake Corporation to develop methodologies for identification and enhancement of stripper wells with economic upside potential. These industry partners previously provided us with data for more than 700 wells in northwestern Pennsylvania. Phase 1 goals of this project are to develop and validate methodologies that can quickly and cost-effectively identify wells with enhancement potential. We have enhanced and streamlined our software, and we are beta-testing the final stages of our new Microsoft{trademark} Access/Excel based software. We have processed all well information and identified potential candidate wells that can be used in Phase 2 to validate the new methodologies. In addition, the final technical report is almost finished and a draft version is being reviewed by Gary Covatch.

Charles M. Boyer II; Ronald J. MacDonald P.G.

2002-04-01T23:59:59.000Z

493

Well purge and sample apparatus and method  

DOE Patents [OSTI]

The present invention specifically permits purging and/or sampling of a well but only removing, at most, about 25% of the fluid volume compared to conventional methods and, at a minimum, removing none of the fluid volume from the well. The invention is an isolation assembly with a packer, pump and exhaust, that is inserted into the well. The isolation assembly is designed so that only a volume of fluid between the outside diameter of the isolation assembly and the inside diameter of the well over a fluid column height from the bottom of the well to the top of the active portion (lower annulus) is removed. The packer is positioned above the active portion thereby sealing the well and preventing any mixing or contamination of inlet fluid with fluid above the packer. Ports in the wall of the isolation assembly permit purging and sampling of the lower annulus along the height of the active portion. 8 figs.

Schalla, R.; Smith, R.M.; Hall, S.H.; Smart, J.E.; Gustafson, G.S.

1995-10-24T23:59:59.000Z

494

Well purge and sample apparatus and method  

DOE Patents [OSTI]

The present invention specifically permits purging and/or sampling of a well but only removing, at most, about 25% of the fluid volume compared to conventional methods and, at a minimum, removing none of the fluid volume from the well. The invention is an isolation assembly with a packer, pump and exhaust, that is inserted into the well. The isolation assembly is designed so that only a volume of fluid between the outside diameter of the isolation assembly and the inside diameter of the well over a fluid column height from the bottom of the well to the top of the active portion (lower annulus) is removed. The packer is positioned above the active portion thereby sealing the well and preventing any mixing or contamination of inlet fluid with fluid above the packer. Ports in the wall of the isolation assembly permit purging and sampling of the lower annulus along the height of the active portion.

Schalla, Ronald (Kennewick, WA); Smith, Ronald M. (Richland, WA); Hall, Stephen H. (Kennewick, WA); Smart, John E. (Richland, WA); Gustafson, Gregg S. (Redmond, WA)

1995-01-01T23:59:59.000Z

495

Numerical Modeling of Cased-hole Instability in High Pressure and High Temperature Wells  

E-Print Network [OSTI]

is predicted to concentrate in the casing-cement system confined by the sandstone. Casing wear in the cased-hole system causes significant casing strength reduction, possibly resulting in the casing-cement tangential collapse. In this study, an approach...

Shen, Zheng 1983-

2012-11-12T23:59:59.000Z

496

Temperature dependence of electron transfer in coupled quantum wells Amlan Majumdara)  

E-Print Network [OSTI]

Laboratory, Adelphi, Maryland 20783 J. L. Reno Sandia National Laboratories, Albuquerque, New Mexico 87185 L that are deduced using corrugated QWIPs and find that electron transfer is efficient only when thermionic emission transport mechanisms, can change differ- ently for the two QWs within each QW pair because of dif- ferent

Rokhinson, Leonid

497

Boom And Bust With The Latest 2M Temperature Surveys- Dead Horse Wells,  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentrating SolarElectricEnergyCTBarre BiomassTHIS PAGE ISJumpSphereBonitaBoolean Jump

498

Single-well Low Temperature CO2- based Engineered Geothemal System |  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion |Energy Usage » SearchEnergyDepartment ofCombustuion | Department of Energy

499

Geothermal wells: a forecast of drilling activity  

SciTech Connect (OSTI)

Numbers and problems for geothermal wells expected to be drilled in the United States between 1981 and 2000 AD are forecasted. The 3800 wells forecasted for major electric power projects (totaling 6 GWe of capacity) are categorized by type (production, etc.), and by location (The Geysers, etc.). 6000 wells are forecasted for direct heat projects (totaling 0.02 Quads per year). Equations are developed for forecasting the number of wells, and data is presented. Drilling and completion problems in The Geysers, The Imperial Valley, Roosevelt Hot Springs, the Valles Caldera, northern Nevada, Klamath Falls, Reno, Alaska, and Pagosa Springs are discussed. Likely areas for near term direct heat projects are identified.

Brown, G.L.; Mansure, A.J.; Miewald, J.N.

1981-07-01T23:59:59.000Z

500

Wells, Borings, and Underground Uses (Minnesota)  

Broader source: Energy.gov [DOE]

This section regulates wells, borings, and underground storage with regards to protecting groundwater resources. The Commissioner of the Department of Health has jurisdiction, and can grant permits...