Global plate motion frames: Toward a unified model
NASA Astrophysics Data System (ADS)
Torsvik, Trond H.; Müller, R. Dietmar; van der Voo, Rob; Steinberger, Bernhard; Gaina, Carmen
2008-09-01
Plate tectonics constitutes our primary framework for understanding how the Earth works over geological timescales. High-resolution mapping of relative plate motions based on marine geophysical data has followed the discovery of geomagnetic reversals, mid-ocean ridges, transform faults, and seafloor spreading, cementing the plate tectonic paradigm. However, so-called "absolute plate motions," describing how the fragments of the outer shell of the Earth have moved relative to a reference system such as the Earth's mantle, are still poorly understood. Accurate absolute plate motion models are essential surface boundary conditions for mantle convection models as well as for understanding past ocean circulation and climate as continent-ocean distributions change with time. A fundamental problem with deciphering absolute plate motions is that the Earth's rotation axis and the averaged magnetic dipole axis are not necessarily fixed to the mantle reference system. Absolute plate motion models based on volcanic hot spot tracks are largely confined to the last 130 Ma and ideally would require knowledge about the motions within the convecting mantle. In contrast, models based on paleomagnetic data reflect plate motion relative to the magnetic dipole axis for most of Earth's history but cannot provide paleolongitudes because of the axial symmetry of the Earth's magnetic dipole field. We analyze four different reference frames (paleomagnetic, African fixed hot spot, African moving hot spot, and global moving hot spot), discuss their uncertainties, and develop a unifying approach for connecting a hot spot track system and a paleomagnetic absolute plate reference system into a "hybrid" model for the time period from the assembly of Pangea (˜320 Ma) to the present. For the last 100 Ma we use a moving hot spot reference frame that takes mantle convection into account, and we connect this to a pre-100 Ma global paleomagnetic frame adjusted 5° in longitude to smooth the reference frame transition. Using plate driving force arguments and the mapping of reconstructed large igneous provinces to core-mantle boundary topography, we argue that continental paleolongitudes can be constrained with reasonable confidence.
Method of making multilayered titanium ceramic composites
Fisher, G.T. II; Hansen, J.S.; Oden, L.L.; Turner, P.C.; Ochs, T.L.
1998-08-25
A method making a titanium ceramic composite involves forming a hot pressed powder body having a microstructure comprising at least one titanium metal or alloy layer and at least one ceramic particulate reinforced titanium metal or alloy layer and hot forging the hot pressed body followed by hot rolling to substantially reduce a thickness dimension and substantially increase a lateral dimension thereof to form a composite plate or sheet that retains in the microstructure at least one titanium based layer and at least one ceramic reinforced titanium based layer in the thickness direction of the composite plate or sheet. 3 figs.
Method of making multilayered titanium ceramic composites
Fisher, George T., II; Hansen; Jeffrey S.; Oden; Laurance L.; Turner; Paul C.; Ochs; Thomas L.
1998-08-25
A method making a titanium ceramic composite involves forming a hot pressed powder body having a microstructure comprising at least one titanium metal or alloy layer and at least one ceramic particulate reinforced titanium metal or alloy layer and hot forging the hot pressed body follwed by hot rolling to substantially reduce a thickness dimension and substantially increase a lateral dimension thereof to form a composite plate or sheet that retains in the microstructure at least one titanium based layer and at least one ceramic reinforced titanium based layer in the thickness direction of the composite plate or sheet.
Method of making multilayered titanium ceramic composites
Fisher, II, George T.; Hansen, Jeffrey S.; Oden, Laurance L.; Turner, Paul C.; Ochs, Thomas L.
1998-01-01
A method making a titanium ceramic composite involves forming a hot pressed powder body having a microstructure comprising at least one titanium metal or alloy layer and at least one ceramic particulate reinforced titanium metal or alloy layer and hot forging the hot pressed body follwed by hot rolling to substantially reduce a thickness dimension and substantially increase a lateral dimension thereof to form a composite plate or sheet that retains in the microstructure at least one titanium based layer and at least one ceramic reinforced titanium based layer in the thickness direction of the composite plate or sheet.
The Influence of Non-Nociceptive Factors on Hot Plate Latency in Rats
Gunn, Amanda; Bobeck, Erin N.; Weber, Ceri; Morgan, Michael M.
2010-01-01
The hot plate is a widely used test to assess nociception. The effect of non-nociceptive factors (weight, sex, activity, habituation, and repeated testing) on hot plate latency was examined. Comparison of body weight and hot plate latency revealed a small but significant inverse correlation (light rats had longer latencies). Habituating rats to the test room for 1 hr prior to testing did not decrease hot plate latency except for female rats tested on Days 2 - 4. Hot plate latency decreased with repeated daily testing, but this was not caused by a decrease in locomotor activity or learning to respond. Activity on the hot plate was consistent across all four trials, and prior exposure to a room temperature plate caused a similar decrease in latency as rats tested repeatedly on the hot plate. Despite this decrease in baseline hot plate latency, there was no difference in morphine antinociceptive potency. The present study shows that weight, habituation to the test room, and repeated testing can alter baseline hot plate latency, but these effects are small and have relatively little impact on morphine antinociception. PMID:20797920
The influence of non-nociceptive factors on hot-plate latency in rats.
Gunn, Amanda; Bobeck, Erin N; Weber, Ceri; Morgan, Michael M
2011-02-01
The hot plate is a widely used test to assess nociception. The effect of non-nociceptive factors (weight, sex, activity, habituation, and repeated testing) on hot-plate latency was examined. Comparison of body weight and hot-plate latency revealed a small but significant inverse correlation (light rats had longer latencies). Habituating rats to the test room for 1 hour prior to testing did not decrease hot-plate latency except for female rats tested on days 2 to 4. Hot-plate latency decreased with repeated daily testing, but this was not caused by a decrease in locomotor activity or learning to respond. Activity on the hot plate was consistent across all 4 trials, and prior exposure to a room-temperature plate caused a similar decrease in latency as rats tested repeatedly on the hot plate. Despite this decrease in baseline hot-plate latency, there was no difference in morphine antinociceptive potency. The present study shows that weight, habituation to the test room, and repeated testing can alter baseline hot-plate latency, but these effects are small and have relatively little impact on morphine antinociception. This manuscript shows that non-nociceptive factors such as body weight, habituation, and repeated testing can alter hot-plate latency, but these factors do not alter morphine potency. In sum, the hot-plate test is an easy to use and reliable method to assess supraspinally organized nociceptive responses. Copyright © 2011 American Pain Society. Published by Elsevier Inc. All rights reserved.
ArF scanner performance improvement by using track integrated CD optimization
NASA Astrophysics Data System (ADS)
Huang, Jacky; Yu, Shinn-Sheng; Ke, Chih-Ming; Wu, Timothy; Wang, Yu-Hsi; Gau, Tsai-Sheng; Wang, Dennis; Li, Allen; Yang, Wenge; Kaoru, Araki
2006-03-01
In advanced semiconductor processing, shrinking CD is one of the main objectives when moving to the next generation technology. Improving CD uniformity (CDU) with shrinking CD is one of the biggest challenges. From ArF lithography CD error budget analysis, PEB (post exposure bake) contributes more than 40% CD variations. It turns out that hot plate performance such as CD matching and within-plate temperature control play key roles in litho cell wafer per hour (WPH). Traditionally wired or wireless thermal sensor wafers were used to match and optimize hot plates. However, sensor-to-sensor matching and sensor data quality vs. sensor lifetime or sensor thermal history are still unknown. These concerns make sensor wafers more suitable for coarse mean-temperature adjustment. For precise temperature adjustment, especially within-hot-plate temperature uniformity, using CD instead of sensor wafer temperature is a better and more straightforward metrology to calibrate hot plates. In this study, we evaluated TEL clean track integrated optical CD metrology (IM) combined with TEL CD Optimizer (CDO) software to improve 193-nm resist within-wafer and wafer-to-wafer CD uniformity. Within-wafer CD uniformity is mainly affected by the temperature non-uniformity on the PEB hot plate. Based on CD and PEB sensitivity of photo resists, a physical model has been established to control the CD uniformity through fine-tuning PEB temperature settings. CD data collected by track integrated CD metrology was fed into this model, and the adjustment of PEB setting was calculated and executed through track internal APC system. This auto measurement, auto feed forward, auto calibration and auto adjustment system can reduce the engineer key-in error and improve the hot plate calibration cycle time. And this PEB auto calibration system can easily bring hot-plate-to-hot-plate CD matching to within 0.5nm and within-wafer CDU (3σ) to less than 1.5nm.
Repeat ridge jumps associated with plume-ridge interaction, melt transport, and ridge migration
NASA Astrophysics Data System (ADS)
Mittelstaedt, Eric; Ito, Garrett; van Hunen, Jeroen
2011-01-01
Repeated shifts, or jumps, of mid-ocean ridge segments toward nearby hot spots can produce large, long-term changes to the geometry and location of the tectonic plate boundaries. Ridge jumps associated with hot spot-ridge interaction are likely caused by several processes including shear on the base of the plate due to expanding plume material as well as reheating of lithosphere as magma passes through it to feed off-axis volcanism. To study how these processes influence ridge jumps, we use numerical models to simulate 2-D (in cross section) viscous flow of the mantle, viscoplastic deformation of the lithosphere, and melt migration upward from the asthenospheric melting zone, laterally along the base of the lithosphere, and vertically through the lithosphere. The locations and rates that magma penetrates and heats the lithosphere are controlled by the time-varying accumulation of melt beneath the plate and the depth-averaged lithospheric porosity. We examine the effect of four key parameters: magmatic heating rate of the lithosphere, plate spreading rate, age of the seafloor overlying the plume, and the plume-ridge migration rate. Results indicate that the minimum value of the magmatic heating rate needed to initiate a ridge jump increases with plate age and spreading rate. The time required to complete a ridge jump decreases with larger values of magmatic heating rate, younger plate age, and faster spreading rate. For cases with migrating ridges, models predict a range of behaviors including repeating ridge jumps, much like those exhibited on Earth. Repeating ridge jumps occur at moderate magmatic heating rates and are the result of changes in the hot spot magma flux in response to magma migration along the base of an evolving lithosphere. The tendency of slow spreading to promote ridge jumps could help explain the observed clustering of hot spots near the Mid-Atlantic Ridge. Model results also suggest that magmatic heating may significantly thin the lithosphere, as has been suggested at Hawaii and other hot spots.
Bounds on geologically current rates of motion of groups of hot spots
NASA Astrophysics Data System (ADS)
Wang, Chengzu; Gordon, Richard G.; Zhang, Tuo
2017-06-01
It is widely believed that groups of hot spots in different regions of the world are in relative motion at rates of 10 to 30 mm a-1 or more. Here we present a new method for analyzing geologically current motion between groups of hot spots beneath different plates. In an inversion of 56 globally distributed, equally weighted trends of hot spot tracks, the dispersion is dominated by differences in trend between different plates rather than differences within plates. Nonetheless the rate of hot spot motion perpendicular to the direction of absolute plate motion, vperp, differs significantly from zero for only 3 of 10 plates and then by merely 0.3 to 1.4 mm a-1. The global mean upper bound on |vperp| is 3.2 ± 2.7 mm a-1. Therefore, hot spots move slowly and can be used to define a global reference frame for plate motions.
A passive guard for low thermal conductivity measurement of small samples by the hot plate method
NASA Astrophysics Data System (ADS)
Jannot, Yves; Degiovanni, Alain; Grigorova-Moutiers, Veneta; Godefroy, Justine
2017-01-01
Hot plate methods under steady state conditions are based on a 1D model to estimate the thermal conductivity, using measurements of the temperatures T 0 and T 1 of the two sides of the sample and of the heat flux crossing it. To be consistent with the hypothesis of the 1D heat flux, either a hot plate guarded apparatus is used, or the temperature is measured at the centre of the sample. On one hand the latter method can be used only if the ratio thickness/width of the sample is sufficiently low and on the other hand the guarded hot plate method requires large width samples (typical cross section of 0.6 × 0.6 m2). That is why both methods cannot be used for low width samples. The method presented in this paper is based on an optimal choice of the temperatures T 0 and T 1 compared to the ambient temperature T a, enabling the estimation of the thermal conductivity with a centered hot plate method, by applying the 1D heat flux model. It will be shown that these optimal values do not depend on the size or on the thermal conductivity of samples (in the range 0.015-0.2 W m-1 K-1), but only on T a. The experimental results obtained validate the method for several reference samples for values of the ratio thickness/width up to 0.3, thus enabling the measurement of the thermal conductivity of samples having a small cross-section, down to 0.045 × 0.045 m2.
Low-Cost Magnetic Stirrer from Recycled Computer Parts with Optional Hot Plate
ERIC Educational Resources Information Center
Guidote, Armando M., Jr.; Pacot, Giselle Mae M.; Cabacungan, Paul M.
2015-01-01
Magnetic stirrers and hot plates are key components of science laboratories. However, these are not readily available in many developing countries due to their high cost. This article describes the design of a low-cost magnetic stirrer with hot plate from recycled materials. Some of the materials used are neodymium magnets and CPU fans from…
Sensitivity Characterization of Pressed Energetic Materials using Flyer Plate Mesoscale Simulations
NASA Astrophysics Data System (ADS)
Rai, Nirmal; Udaykumar, H. S.
Heterogeneous energetic materials like pressed explosives have complicated microstructure and contain various forms of heterogeneities such as pores, micro-cracks, energetic crystals etc. It is widely accepted that the presence of these heterogeneities can affect the sensitivity of these materials under shock load. The interaction of shock load with the microstructural heterogeneities may leads to the formation of local heated regions known as ``hot spots''. Chemical reaction may trigger at the hot spot regions depending on the hot spot temperature and the duration over which the temperature can be maintained before phenomenon like heat conduction, rarefaction waves withdraws energy from it. There are different mechanisms which can lead to the formation of hot spots including void collapse. The current work is focused towards the sensitivity characterization of two HMX based pressed energetic materials using flyer plate mesoscale simulations. The aim of the current work is to develop mesoscale numerical framework which can perform simulations by replicating the laboratory based flyer plate experiments. The current numerical framework uses an image processing approach to represent the microstructural heterogeneities incorporated in a massively parallel Eulerian code SCIMITAR3D. The chemical decomposition of HMX is modeled using Henson-Smilowitz reaction mechanism. The sensitivity characterization is aimed towards obtaining James initiation threshold curve and comparing it with the experimental results.
Recovery of energy from geothermal brine and other hot water sources
Wahl, III, Edward F.; Boucher, Frederic B.
1981-01-01
Process and system for recovery of energy from geothermal brines and other hot water sources, by direct contact heat exchange between the brine or hot water, and an immiscible working fluid, e.g. a hydrocarbon such as isobutane, in a heat exchange column, the brine or hot water therein flowing countercurrent to the flow of the working fluid. The column can be operated at subcritical, critical or above the critical pressure of the working fluid. Preferably, the column is provided with a plurality of sieve plates, and the heat exchange process and column, e.g. with respect to the design of such plates, number of plates employed, spacing between plates, area thereof, column diameter, and the like, are designed to achieve maximum throughput of brine or hot water and reduction in temperature differential at the respective stages or plates between the brine or hot water and the working fluid, and so minimize lost work and maximize efficiency, and minimize scale deposition from hot water containing fluid including salts, such as brine. Maximum throughput approximates minimum cost of electricity which can be produced by conversion of the recovered thermal energy to electrical energy.
NASA Astrophysics Data System (ADS)
Stacey, C.; Simpkin, A. J.; Jarrett, R. N.
2016-11-01
The National Physical Laboratory (NPL) has developed a new variation on the established guarded hot plate technique for steady-state measurements of thermal conductivity. This new guarded hot plate has been specifically designed for making measurements on specimens with a thickness that is practical for advanced industrial composite materials and applications. During the development of this new guarded hot plate, NPL carried out an experimental investigation into methods for minimising the thermal contact resistance between the test specimen and the plates of the apparatus. This experimental investigation included tests on different thermal interface materials for use in another NPL facility based on a commercial guarded heat flow meter apparatus conforming to standard ASTM E1530-11. The results show the effect of applying different quantities of the type of heat transfer compound suggested in ASTM E1530-11 (clause 10.7.3) and also the effect on thermal resistance of alternative types of thermal interface products. The optimum quantities of two silicone greases were determined, and a silicone grease filled with copper was found to offer the best combination of repeatability, small hysteresis effect and a low thermal contact resistance. However, two products based on a textured indium foil and pyrolytic graphite sheet were found to offer similar or better reductions in thermal contact resistance, but with quicker, easier application and the advantages of protecting the apparatus plates from damage and being useable with specimen materials that would otherwise absorb silicone grease.
Utilization of Additive Manufacturing for Aerospace Heat Exchangers
2016-02-29
is made up of flat plates that are layered on top of each other creating air passages in between the plates where the hot liquid and cold liquid flow...electron beam- based) for two-dimensional scanning of the heat source on the powder layer , stages that decrease the build plate and increase the powder...build plate and result in uneven coating of subsequent powder layers or complete failure of the system to recoat. The perturbations in recoater
NASA Astrophysics Data System (ADS)
Hudec, Ján; Glorieux, Christ; Dieška, Peter; Kubičár, Ľudovít
2016-07-01
The Hot-ball method is an innovative transient method for measuring thermophysical properties. The principle is based on heating of a small ball, incorporated in measured medium, by constant heating power and simultaneous measuring of the ball's temperature response since the heating was initiated. The shape of the temperature response depends on thermophysical properties of the medium, where the sensor is placed. This method is patented by Institute of Physics, SAS, where the method and sensors based on this method are being developed. At the beginning of the development of sensors for this method we were oriented on monitoring applications, where relative precision is much more important than accuracy. Meanwhile, the quality of sensors was improved good enough to be used for a new application - absolute measuring of thermophysical parameters of low thermally conductive materials. This paper describes experimental verification and validation of measurement by hot-ball method. Thanks to cooperation with Laboratory of Soft Matter and Biophysics of Catholic University of Leuven in Belgium, established Guarded Hot Plate method was used as a reference. Details about measuring setups, description of the experiments and results of the comparison are presented.
Memristive Responses of Jammed Granular Copper Array Sensors to Mechanical Stress
2014-03-27
called Industrial Tectonics Inc. (itiball.com) with the statement of 99.95% minimum copper; stating the residual is most likely silver [12]. Their...atmosphere hot plate and quartz tube furnace with controlled atmosphere were used to oxidize the spheres at various temperatures, the hot plate ...combination spheres, as was seen by Branly. Using a nitric acid etch and 15 minute (min.) hot plate oxidized sphere array consisting of four spheres
NASA Astrophysics Data System (ADS)
Song, Y. L.; Li, C. S.; Ma, B.; Han, Y. H.
2017-05-01
Asymmetric hot rolling (ASHR) with a mismatch speed ratio of 1.15 in a single pass was applied to Fe-18Mn-18Cr-0.5N steel and was compared with symmetric hot rolling (SHR). The results indicated that a through-thickness microstructure gradient was formed in the plate due to the shear strain (0.36) introduced by ASHR. A fine-grained layer with the average size of 3 μm was achieved at the top surface of ASHR plate, while numerous elongated grains with a few recrystallized grains were presented at the center layer. The texture was distributed randomly at the top surface of ASHR plate, and a weaker intensity of typical hot-rolled texture in austenitic steel was obtained at the center layer of ASHR plate compared to SHR plate. An excellent combination of microhardness, strength and ductility was obtained in the ASHR plate, which was attributed to gradient microstructure induced by ASHR.
OUT Success Stories: Solar Hot Water Technology
DOE R&D Accomplishments Database
Clyne, R.
2000-08-01
Solar hot water technology was made great strides in the past two decades. Every home, commercial building, and industrial facility requires hot water. DOE has helped to develop reliable and durable solar hot water systems. For industrial applications, the growth potential lies in large-scale systems, using flat-plate and trough-type collectors. Flat-plate collectors are commonly used in residential hot water systems and can be integrated into the architectural design of the building.
ERIC Educational Resources Information Center
Vink, Gregory E.; And Others
1985-01-01
Hot spots are isolated areas of geologic activity where volcanic eruptions, earthquakes, and upwelling currents occur far from plate boundaries. These mantle plumes are relatively stable and crustal plates drift over them. The nature and location of hot spots (with particular attention to the Hawaiian Islands and Iceland) are discussed. (DH)
Layered composites made from bimetallic strips produced by plasma spraying of TiAl on niobium
NASA Astrophysics Data System (ADS)
Burmistrov, V. I.; Antonova, A. V.; Povarova, K. B.; Bannykh, I. O.
2007-12-01
The production and structure of a multilayer TiAl/Nb composite material made from bimetallic TiAl/Nb strips fabricated by plasma spraying of TiAl granules onto niobium plates are studied. Here, 3-mm-and 2-mm-thick plates of a layered composite material (LCM) are produced by hot isostatic pressing of a stack of 35 bimetallic plates followed by hot rolling (the total degree of reduction is 78.6 and 85.7%, respectively). The LCM consists of discontinuous TiAl layers separated by niobium layers, and the adhesion between the layers is good. Diffusional intermediate layers form at the TiAl/Nb interfaces in the 3-mm-thick LCM and consist of the following two solid solutions: an α2-Ti3Al-based solid solution contains up to 28 at % Nb, and a niobiumbased solid solution contains up to 27 at % Ti and 32 at % Al. The diffusional intermediate layers in the 2-mmthick LCM plates consist of an α2-Ti3Al-based solid solution with up to 16.0 at % Nb; a τ-Ti3Al2Nb-or Ti4Al3Nb-based solid solution with 51.5 at % Ti, 32 at % Al, and 16.5 at % Nb; and a niobium-based solid solution with up to 22 at % Ti and 30.5 at % Al. When a bimetallic TiAl/Nb strip is fabricated by plasma spraying of granules of the Ti-48 at % Al alloy, this alloy is depleted of aluminum to 42 45 at %, and the fraction of the α2-Ti3Al phase in the sprayed layer increases. When the LCM is produced by hot isostatic pressing followed by hot rolling, the layer of plain niobium (Nb1) dissolves up to 5 at % Ti and 7 at % Al.
Solar space and water heating system installed at Charlottesville, Virginia
NASA Technical Reports Server (NTRS)
1980-01-01
The solar energy system located at David C. Wilson Neuropsychiatric Hospital, Charlottesville, Virginia, is described. The solar energy system consists of 88 single glazed, Sunworks 'Solector' copper base plate collector modules, hot water coils in the hot air ducts, a Domestic Hot Water (DHW) preheat tank, a 3,000 gallon concrete urethane insulated storage tank and other miscellaneous components. Extracts from the site files, specifications, drawings, installation, operation and maintenance instructions are included.
1951-09-15
ended. O^J’’" ’•» >i- feud .**■ J ’. I’ /fi ’. . f ■ ^ Conclusions and Recommendations The work reported herein shows that...the chromium-iron alloy plating process is not yet ready for full-scale application to gun tubes. The need for additional beaker-scale work on the...additional work is needed to allow production of uniform good plates each plating trial. The firing-test results showed that adhesion of the plate is not
High-Temperature Thermal Conductivity Measurement Apparatus Based on Guarded Hot Plate Method
NASA Astrophysics Data System (ADS)
Turzo-Andras, E.; Magyarlaki, T.
2017-10-01
An alternative calibration procedure has been applied using apparatus built in-house, created to optimize thermal conductivity measurements. The new approach compared to those of usual measurement procedures of thermal conductivity by guarded hot plate (GHP) consists of modified design of the apparatus, modified position of the temperature sensors and new conception in the calculation method, applying the temperature at the inlet section of the specimen instead of the temperature difference across the specimen. This alternative technique is suitable for eliminating the effect of thermal contact resistance arising between a rigid specimen and the heated plate, as well as accurate determination of the specimen temperature and of the heat loss at the lateral edge of the specimen. This paper presents an overview of the specific characteristics of the newly developed "high-temperature thermal conductivity measurement apparatus" based on the GHP method, as well as how the major difficulties are handled in the case of this apparatus, as compared to the common GHP method that conforms to current international standards.
Effect of nanostructure on rapid boiling of water on a hot copper plate: a molecular dynamics study
NASA Astrophysics Data System (ADS)
Fu, Ting; Mao, Yijin; Tang, Yong; Zhang, Yuwen; Yuan, Wei
2016-08-01
Molecular dynamic simulations are performed to study the effects of nanostructure on rapid boiling of water that is suddenly heated by a hot copper plate. The results show that the nanostructure has significant effects on energy transfer from solid copper plate to liquid water and phase change process from liquid water to vapor. The liquid water on the solid surface rapidly boil after contacting with an extremely hot copper plate and consequently a cluster of liquid water moves upward during phase change. The temperature of the water film when it separates from solid surface and its final temperature when the system is at equilibrium strongly depend on the size of the nanostructure. These temperatures increase with increasing size of nanostructure. Furthermore, a non-vaporized molecular layer is formed on the surface of the copper plate even continuous heat flux is passing into water domain through the plate.
Improvements To Micro Contact Performance And Reliability
2016-12-22
BAKE : □ 1 min 110°C hot plate bake OPTIONAL - For Grayscale Lithography: 1818 COAT: □ Flood wafer with 1818 □ 4 sec spread at 500 rpm...30 sec spin at 4,000 rpm, ramp=200 □ 75 sec 110°C hot plate bake GRAYSCALE PATTERNING: □ Follow grayscale patterning process for patterns...8217 □ 2 min 200°C hot plate bake 1818 COAT: □ Flood wafer with 1818 □ 4 sec spread at 500 rpm □ 30 sec spin at 4,000 rpm, ramp=200 □ 75 sec 110
NASA Astrophysics Data System (ADS)
Zhou, Qing; Jin, Zhiwen; Li, Hui; Wang, Jizheng
2016-02-01
To fabricate high-performance metal-halide perovskite solar cells, a thermal annealing process is indispensable in preparing high quality perovskite film. And usually such annealing is performed on hot plate. However hot-plate annealing could cause problems such as inhomogeneous heating (induced by non-tight contact between the sample and the plate), it is also not fit for large scale manufactory. In this paper, we conduct the annealing process in air-heated oven under various humidity environments, and compared the resulted films (CH3NH3PbI3-xClx) and devices (Al/PC61BM/CH3NH3PbI3-xClx/PEDOT:PSS/ITO/glass) with that obtained via hot-plate annealing. It is found that the air-heated-oven annealing is superior to the hot-plate annealing: the annealing time is shorter, the films are more uniform, and the devices exhibit higher power conversion efficiency and better uniformity. The highest efficiencies achieved for the oven and hot-plate annealing processes are 14.9% and 13.5%, and the corresponding standard deviations are 0.5% and 0.8%, respectively. Our work here indicates that air-heated-oven annealing could be a more reliable and more efficient way for both lab research and large-scale production.
Code of Federal Regulations, 2012 CFR
2012-10-01
... Containers, and Linings § 178.33-5 Material. (a) Uniform quality steel plate such as black plate, electro-tin plate, hot dipped tin plate, tern plate or other commercially accepted can making plate; or nonferrous...
Code of Federal Regulations, 2014 CFR
2014-10-01
... Containers, and Linings § 178.33-5 Material. (a) Uniform quality steel plate such as black plate, electro-tin plate, hot dipped tin plate, tern plate or other commercially accepted can making plate; or nonferrous...
Code of Federal Regulations, 2011 CFR
2011-10-01
... Containers, and Linings § 178.33-5 Material. (a) Uniform quality steel plate such as black plate, electro-tin plate, hot dipped tin plate, tern plate or other commercially accepted can making plate; or nonferrous...
Code of Federal Regulations, 2013 CFR
2013-10-01
... Containers, and Linings § 178.33-5 Material. (a) Uniform quality steel plate such as black plate, electro-tin plate, hot dipped tin plate, tern plate or other commercially accepted can making plate; or nonferrous...
Kiln for hot-pressing compacts in a continuous manner
Reynolds, C.D Jr.
1983-08-08
The invention is directed to a hot pressing furnace or kiln which is capable of preheating, hot pressing, and cooling a plurality of articles in a sequential and continuous manner. The hot pressing furnace of the present invention comprises an elongated, horizontally disposed furnace capable of holding a plurality of displaceable pusher plates each supporting a die body loaded with refractory or ceramic material to be hot pressed. Each of these plates and the die body supported thereby is sequentially pushed through the preheating zone, a temperature stabilizing and a hot pressing zone, and a cooling zone so as to provide a continuous hot-pressing operation of a plurality of articles.
Kiln for hot-pressing compacts in a continuous manner
Reynolds, Jr., Carl D.
1985-01-01
The present invention is directed to a hot pressing furnace or kiln which is capable of preheating, hot pressing, and cooling a plurality of articles in a sequential and continuous manner. The hot pressing furnace of the present invention comprises an elongated, horizontally disposed furnace capable of holding a plurality of displaceable pusher plates each supporting a die body loaded with refractory or ceramic material to be hot pressed. Each of these plates and the die body supported thereby is sequentially pushed through the preheating zone, a temperature stabilizing and a hot pressing zone, and a cooling zone so as to provide a continuous hot-pressing operation of a plurality of articles.
NASA Astrophysics Data System (ADS)
Hendrarsakti, J.; Ichsan, Y.
2016-09-01
This research was conducted to assess the direct use of geothermal energy for blood warmer. The heating plate was made form aluminium plates with dimensions of 100 x 200 mm and then fed from the hot water heater. Tests were conducted in the laboratory where geothermal source water is replaced with the heat generated from the heater. The hot water from the heater in the temperature range 55°C - 60°C flowed into vertical chamber. Setting the temperature of the hot water heater is done by changing the flow of hot water coming out of the heater. Results showed that the value of a standard deviation of plate temperature was about 0.42 °C, so it can be said isothermal accordance with design requirement and objective. The test data used for the analysis of the manufacture of the heating plate in the blood warmer to regulate the discharge of hot water at intervals of 21.47 mL/s to 24.8 mL/s to obtain a temperature of 37.20 °C - 40.15 °C. Geothermal energy has the potential for blood warmer because blood warmer is part of the energy cascade in a temperature range of 40°C to 60°C
An experimental investigation with artificial sunlight of a solar hot-water heater
NASA Technical Reports Server (NTRS)
Simon, F. F.
1976-01-01
Thermal performance measurements were made of a commercial solar hot water heater in a solar simulator to determine basic performance characteristics of a traditional type of flat plate collector, with and without side reflectors (to increase the solar flux). Information on each of the following was obtained; (1) the effect of flow and incidence angle on the efficiency of a flat plate collector (but only without side reflectors); (2) transient performance under flow and nonflow conditions; (3) the effectiveness of reflectors to increase collector efficiency for a zero radiation angle at fluid temperatures required for solar air conditioning; and (4) the limits of applicability of a collector efficiency correlation based on the Hottel Whillier equation.
Physics of heat pipe rewetting
NASA Technical Reports Server (NTRS)
Chan, S. H.
1992-01-01
Although several studies have been made to determine the rewetting characteristics of liquid films on heated rods, tubes, and flat plates, no solutions are yet available to describe the rewetting process of a hot plate subjected to a uniform heating. A model is presented to analyze the rewetting process of such plates with and without grooves. Approximate analytical solutions are presented for the prediction of the rewetting velocity and the transient temperature profiles of the plates. It is shown that the present rewetting velocity solution reduces correctly to the existing solution for the rewetting of an initially hot isothermal plate without heating from beneath the plate. Numerical solutions have also been obtained to validate the analytical solutions.
NASA Astrophysics Data System (ADS)
Zulkifli, Muhammad Nubli; Ilias, Izzudin; Abas, Amir; Muhamad, Wan Mansor Wan
2017-09-01
Thermoelectric generator (TEG) is the solid state device that converts the thermal gradient into electrical energy. TEG is widely used as the renewable energy source especially for the electronic equipment that operates with the small amount of electrical power. In the present analysis, the finite element analysis (FEA) using ANSYS is conducted on a model of the TEG attached with the aluminium, Al plate on the hot side of the TEG. This simple construction of TEG model was built in order to be used in the waste heat recovery of solar application. It was shown that the changes of the area and thickness of the Al plate increased the temperature gradient between hot and cold sides of TEG. This directly increase the voltage produced by the TEG based on the Seeback effect. The increase of the thermal gradient due to the increment of thickness and width of Al plate might be because of the increase of thermal resistance of Al plate. This finding provides a valuable data in design process to build a good TEG attached with Al plate for the waste heat recovery of solar application.
Solar-energy heats a transportation test center--Pueblo, Colorado
NASA Technical Reports Server (NTRS)
1981-01-01
Petroleum-base, thermal energy transport fluid circulating through 583 square feet of flat-plate solar collectors accumulates majority of energy for space heating and domestic hot-water of large Test Center. Report describes operation, maintenance, and performance of system which is suitable for warehouses and similar buildings. For test period from February 1979 to January 1980, solar-heating fraction was 31 percent, solar hot-water fraction 79 percent.
Anti-inflammatory and analgesic activity of Peperomia pellucida (L.) HBK (Piperaceae).
de Fátima Arrigoni-Blank, Maria; Dmitrieva, Elena G; Franzotti, Elaine Maria; Antoniolli, Angelo Roberto; Andrade, Márcio Roberto; Marchioro, Murilo
2004-04-01
An aqueous extract of the aerial part of Peperomia pellucida (L.) HBK (Piperaceae) was tested for anti-inflammatory (paw edema induced by carrageenin and arachidonic acid) and analgesic activity (abdominal writhes and hot plate) in rats and mice, respectively. Oral administration of 200 and 400 mg/kg of the aqueous extract exhibited an anti-inflammatory activity in the carrageenin test, which was based on interference with prostaglandin synthesis, as confirmed by the arachidonic acid test. In the abdominal writhing test induced by acetic acid, 400 mg/kg of the plant extract had the highest analgesic activity, whereas in the hot-plate test the best dose was 100 mg/kg. The LD(50) showed that Peperomia pellucida (5000 mg/kg) presented low toxicity.
Li, Manfeng; Zhang, Hua; Ju, Yonglin
2012-07-01
A double-sided guarded hot plate apparatus (GHP) is specifically designed, fabricated, and constructed for the measurement of thermal conductivities of insulation specimens operated down to liquid nitrogen temperature (-196 °C), at different controlled pressures from 0.005 Pa to 0.105 MPa. The specimens placed in this apparatus are 300 mm in diameter at various thicknesses ranging from 4 mm to 40 mm. The apparatus is different from traditional GHP in terms of structure, supporting and heating method. The details of the design and construction of the hot plate, the cold plates, the suspensions, the clampings, and the vacuum chamber of the system are presented. The measurement methods of the temperatures, the input power, the meter area, and the thickness of the specimens are given. The apparatus is calibrated with teflon plates as sample and the maximum deviation from the published data is about 6% for thermal conductivity. The uncertainties for the measurement are also discussed in this paper.
Highly Sensitive Sensors Based on Metal-Oxide Nanocolumns for Fire Detection.
Lee, Kwangjae; Shim, Young-Seok; Song, Young Geun; Han, Soo Deok; Lee, Youn-Sung; Kang, Chong-Yun
2017-02-07
A fire detector is the most important component in a fire alarm system. Herein, we present the feasibility of a highly sensitive and rapid response gas sensor based on metal oxides as a high performance fire detector. The glancing angle deposition (GLAD) technique is used to make the highly porous structure such as nanocolumns (NCs) of various metal oxides for enhancing the gas-sensing performance. To measure the fire detection, the interface circuitry for our sensors (NiO, SnO₂, WO₃ and In₂O₃ NCs) is designed. When all the sensors with various metal-oxide NCs are exposed to fire environment, they entirely react with the target gases emitted from Poly(vinyl chlorides) (PVC) decomposed at high temperature. Before the emission of smoke from the PVC (a hot-plate temperature of 200 °C), the resistances of the metal-oxide NCs are abruptly changed and SnO₂ NCs show the highest response of 2.1. However, a commercial smoke detector did not inform any warning. Interestingly, although the NiO NCs are a p -type semiconductor, they show the highest response of 577.1 after the emission of smoke from the PVC (a hot-plate temperature of 350 °C). The response time of SnO₂ NCs is much faster than that of a commercial smoke detector at the hot-plate temperature of 350 °C. In addition, we investigated the selectivity of our sensors by analyzing the responses of all sensors. Our results show the high potential of a gas sensor based on metal-oxide NCs for early fire detection.
Post exposure bake unit equipped with wafer-shape compensation technology
NASA Astrophysics Data System (ADS)
Goto, Shigehiro; Morita, Akihiko; Oyama, Kenichi; Hori, Shimpei; Matsuchika, Keiji; Taniguchi, Hideyuki
2007-03-01
In 193nm lithography, it is well known that Critical Dimension Uniformity (CDU) within wafer is especially influenced by temperature variation during Post Exposure Bake (PEB) process. This temperature variation has been considered to be caused by the hot plate unit, and improvement of temperature uniformity within hot plate itself has been focused to achieve higher CDU. However, we have found that the impact of the wafer shape on temperature uniformity within wafer can not be ignored when the conventional PEB processing system is applied to an advanced resist technology. There are two factors concerned with the wafer shape. First, gravity force of the wafer itself generates wafer shape bending because wafer is simply supported by a few proximity gaps on the conventional hot plate. Next, through the semiconductor manufacturing process, wafer is gradually warped due to the difference of the surface stress between silicon and deposited film layers (Ex. Si-Oxide, Si-Nitride). Therefore, the variation of the clearance between wafer backside and hot plate surface leads to non-uniform thermal conductivity within wafer during PEB processing, and eventually impacts on the CDU within wafer. To overcome this problem concerned with wafer shape during PEB processing, we have developed the new hot plate equipped with the wafer shape compensation technology. As a result of evaluation, we have confirmed that this new PEB system has an advantage not only for warped wafer but also for flat (bare) wafer.
Pole of rotating analysis of present-day Juan de Fuca plate motion
NASA Technical Reports Server (NTRS)
Nishimura, C.; Wilson, D. S.; Hey, R. N.
1984-01-01
Convergence rates between the Juan de Fuca and North American plates are calculated by means of their relative, present-day pole of rotation. A method of calculating the propagation of errors in addition to the instantaneous poles of rotation is also formulated and applied to determine the Euler pole for Pacific-Juan de Fuca. This pole is vectorially added to previously published poles for North America-Pacific and 'hot spot'-Pacific to obtain North America-Juan de Fuca and 'hot spot'-Juan de Fuca, respectively. The errors associated with these resultant poles are determined by propagating the errors of the two summed angular velocity vectors. Under the assumption that hot spots are fixed with respect to a mantle reference frame, the average absolute velocity of the Juan de Puca plate is computed at approximately 15 mm/yr, thereby making it the slowest-moving of the oceanic plates.
Parthuisot, N.; Binet, M.; Touron-Bodilis, A.; Pougnard, C.; Lebaron, P.; Baudart, J.
2011-01-01
A new method was developed for the rapid and sensitive detection of viable Legionella pneumophila. The method combines specific immunofluorescence (IF) staining using monoclonal antibodies with a bacterial viability marker (ChemChrome V6 cellular esterase activity marker) by means of solid-phase cytometry (SPC). IF methods were applied to the detection and enumeration of both the total and viable L. pneumophila cells in water samples. The sensitivity of the IF methods coupled to SPC was 34 cells liter−1, and the reproducibility was good, with the coefficient of variation generally falling below 30%. IF methods were applied to the enumeration of total and viable L. pneumophila cells in 46 domestic hot water samples as well as in cooling tower water and natural water samples, such as thermal spring water and freshwater samples. Comparison with standard plate counts showed that (i) the total direct counts were always higher than the plate counts and (ii) the viable counts were higher than or close to the plate counts. With domestic hot waters, when the IF assay was combined with the viability test, SPC detected up to 3.4 × 103 viable but nonculturable L. pneumophila cells per liter. These direct IF methods could be a powerful tool for high-frequency monitoring of domestic hot waters or for investigating the occurrence of viable L. pneumophila in both man-made water systems and environmental water samples. PMID:21742913
Metallurgical Aspects of Layered Cracks in Hot-Rolled Plates
NASA Astrophysics Data System (ADS)
Farber, V. M.; Arabey, A. B.; Khotinov, V. A.; Morozova, A. N.; Karabanalov, M. S.
2018-03-01
The nature of separations arising in hot-rolled plates from high-toughness steels of the new generation like 05G2B and of cleavages arising in traditional building steels of type 09G2S is studied. Like and unlike features of separations and cleavages are determined. The concept of "critical stress σb^{cr} " describing the strength of the interlayer boundaries responsible for formation of layered cracks is used to analyze various factors responsible for the susceptibility of rolled plates to layered fracture.
Concentrator hot-spot testing, phase 1
NASA Technical Reports Server (NTRS)
Gonzalez, C. C.
1987-01-01
Results of a study to determine the hot-spot susceptibility of concentrator cells, to provide a hot-spot qualification test for concentrator modules, and to provide guidelines for reducing hot-spot susceptibility are presented. Hot-spot heating occurs in a photovoltaic module when the short-circuit current of a cell is lower than the string operating current forcing the cell into reverse bias with a concurrent power dissipation. Although the basis for the concentrator module hot-spot qualification test is the test developed for flat-plate modules, issues, such as providing cell illumination, introduce additional complexities into the testing procedure. The same general guidelines apply for protecting concentrator modules from hot-spot stressing as apply to flat-plate modules. Therefore, recommendations are made on the number of bypass diodes required per given number of series cells per module or source circuit. In addition, a new method for determining the cell temperature in the laboratory or in the field is discussed.
21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.
Code of Federal Regulations, 2014 CFR
2014-04-01
... of the flask at 150 °F for 2 hours using a hot plate while also maintaining gentle mechanical agitation. Filter the contents of the flask rapidly through No. 42 Whatman filter paper with the aid of suction. Transfer the filtrate to flat glass dishes that are warmed on a hot plate and evaporate the...
Bus bar electrical feedthrough for electrorefiner system
Williamson, Mark; Wiedmeyer, Stanley G; Willit, James L; Barnes, Laurel A; Blaskovitz, Robert J
2013-12-03
A bus bar electrical feedthrough for an electrorefiner system may include a retaining plate, electrical isolator, and/or contact block. The retaining plate may include a central opening. The electrical isolator may include a top portion, a base portion, and a slot extending through the top and base portions. The top portion of the electrical isolator may be configured to extend through the central opening of the retaining plate. The contact block may include an upper section, a lower section, and a ridge separating the upper and lower sections. The upper section of the contact block may be configured to extend through the slot of the electrical isolator and the central opening of the retaining plate. Accordingly, relatively high electrical currents may be transferred into a glovebox or hot-cell facility at a relatively low cost and higher amperage capacity without sacrificing atmosphere integrity.
Dissolved gas concentrations of the geothermal fluids in Taiwan
NASA Astrophysics Data System (ADS)
Chen, Ai-Ti; Yang, Tsanyao Frank
2010-05-01
Taiwan, a geologically active island, is located on the boundary of the Philippine Sea Plate and the Eurasian Plate. High heat flow and geothermal gradient generated by the complex collision and orogeny, warm up the meteoric water and/or the ground water. The heated water becomes geothermal fluids. In previous studies, researchers tried to categorize hot springs based on the appearance, chemical compositions and lithological areas. Because of the chemical inertness, the concentrations and isotopic composition of dissolved noble gases are good indicators of the mantle degassing, geothermal conditions, and so on. In this study, 55 hot springs were collected from different tectonic units. It is the first time to systematically study the hot springs in Taiwan in terms of dissolved gases. Hot spring water is sampled and stored in pre-evacuated glass bottles for analyzing gas compositions. The abundances of noble gases were determined by a quadrupole mass spectrometer based on the isotope dilution technique. Samples with glass vials are introduced to RAD 7 and GC for dissolved Rn and major dissolved gases analyses. Furthermore, helium isotopic ratios and helium-neon ratios are measured on a conventional noble gas mass spectrometer. For hydrochemistry analysis, water samples are analyzed by IC, ICP-MS and titration. We can classify the hot springs samples into three major groups from main anion concentration data; and then, subdivide them into nine minor groups by cation concentration data. Moreover, according to major dissolved gases compositions, three major gas components: CH4, N2 and CO2, are identified. Dissolved noble gases provided more detailed clues about hot springs sources in Taiwan, such as the degree of mixing between meteoric water and deep-source water, which will be further discussed in this study.
Solar hot water system installed at Day's Lodge, Atlanta, Georgia
NASA Technical Reports Server (NTRS)
1980-01-01
The solar energy hot water system installed in the Days Inns of America, Inc., Atlanta, Georgia is described. This system provides for 81 percent of the total hot water demand. There are two separate systems, each serving one building of the lodge (total of 65 suites). The entire system contains only potable city water. The 1024 square feet of Grumman Sunstream Model 332 liquid flat plate collectors and the outside piping drain whenever the collector plates approach freezing or when power is interrupted. Solar heated water from the two above ground cement lined steel tanks (1000 gallon tank) is drawn into the electric Domestic Hot Water (DHW) tanks as hot water is drawn. Electric resistance units in the DHW tanks top off the solar heated water, if needed, to reach thermostat setting.
Hot air impingement on a flat plate using Large Eddy Simulation (LES) technique
NASA Astrophysics Data System (ADS)
Plengsa-ard, C.; Kaewbumrung, M.
2018-01-01
Impinging hot gas jets to a flat plate generate very high heat transfer coefficients in the impingement zone. The magnitude of heat transfer prediction near the stagnation point is important and accurate heat flux distribution are needed. This research studies on heat transfer and flow field resulting from a single hot air impinging wall. The simulation is carried out using computational fluid dynamics (CFD) commercial code FLUENT. Large Eddy Simulation (LES) approach with a subgrid-scale Smagorinsky-Lilly model is present. The classical Werner-Wengle wall model is used to compute the predicted results of velocity and temperature near walls. The Smagorinsky constant in the turbulence model is set to 0.1 and is kept constant throughout the investigation. The hot gas jet impingement on the flat plate with a constant surface temperature is chosen to validate the predicted heat flux results with experimental data. The jet Reynolds number is equal to 20,000 and a fixed jet-to-plate spacing of H/D = 2.0. Nusselt number on the impingement surface is calculated. As predicted by the wall model, the instantaneous computed Nusselt number agree fairly well with experimental data. The largest values of calculated Nusselt number are near the stagnation point and decrease monotonically in the wall jet region. Also, the contour plots of instantaneous values of wall heat flux on a flat plate are captured by LES simulation.
NASA Astrophysics Data System (ADS)
Hameury, J.; Koenen, A.; Hay, B.; Wu, J.; Hammerschmidt, U.; Rafeld, E. K.; Pennewitz, E.; Turzó-András, E.; Strnad, R.; Blahut, A.
2018-01-01
The selection of a material for making the hot and cold plates of high-temperature guarded hot plates (HTGHPs) working up to 800°C is still an issue. The material must be machinable, have a high mechanical stability to keep the high level of flatness of the plates and have a high thermal conductivity and a high resistance to oxidation when used in air. Nickel 201 alloy has been used in several instruments, but has shown, sometimes, problems of mechanical stability. The total hemispherical emissivity of the plates must be higher than 0.8 as recommended by the standards. Three ceramic materials, a silicon infiltrated silicon carbide (SiSiC), a machinable aluminum nitride and a sintered aluminum nitride (AlN) with high thermal conductivity claimed at ambient temperature, were selected for tests in thermal conductivity and opacity to thermal radiation. Three paints withstanding high temperatures were tested in total hemispherical emissivity and durability at high temperature. Above 600°C, Nickel 201 alloy has a higher thermal conductivity than the three ceramics. Below 600°C, the SiSiC and the sintered AlN have a thermal conductivity significantly higher than Nickel 201, but the sintered AlN shows a wide transparency spectral band at short wavelengths (below 6.5 μ m). Above 300°C, the three paints have a total hemispherical emissivity above 0.8. One of the paints has polluted the specimens of an insulation material tested in thermal conductivity up to 650°C. The other two can be recommended to coat the hot and cold plates of HTGHPs used up to 800°C.
Hot-spot qualification testing of concentrator modules
NASA Technical Reports Server (NTRS)
Gonzalez, C. C.; Sugimura, R. S.; Ross, R. G., Jr.
1987-01-01
Results of a study to determine the hot-spot susceptibility of concentrator cells, to provide a hot-spot qualification test for concentrator modules, and to provide guidelines for reducing hot-spot susceptibility are presented. Hot-spot heating occurs in a photovoltaic module when the short-circuit current of a cell is lower than the string operating current, forcing the cell into reverse bias with a concurrent power dissipation. Although the basis for the concentrator-module hot-spot qualification test is the test developed for flat-plate modules, issues such as providing cell illumination introduce additional complexities into the testing procedure. The results indicate that the same general guidelines apply to protecting concentrator modules from hot-spot stressing as apply to flat-plate modules, and recommendations are made on the number of bypass diodes required per given number of series cells per module or source circuit. A method for determining the cell temperature in the laboratory or in the field is discussed.
NASA Astrophysics Data System (ADS)
Pigott, J. S.; Ditmer, D. A.; Fischer, R. A.; Reaman, D. M.; Davis, R. J.; Panero, W. R.
2014-12-01
To model and predict the structure, dynamics, and composition of Earth's deep interior, accurate and precise measurements of thermal expansion and compressibility are required. The laser-heated diamond-anvil cell (LHDAC) coupled with synchrotron-based x-ray diffraction (XRD) is a powerful tool to determine pressure-volume-temperature (P-V-T) relationships. However, LHDAC experiments may be hampered by non-uniform heating caused by the mixing of transparent materials with opaque laser absorbers. Additionally, radial temperature gradients are exacerbated by small misalignments (1-3 µm) of the x-ray beam with respect to the center of the laser-heated hotspot. We have fabricated three-dimensional, controlled-geometry, double hot-plate samples. In this double hot-plate arrangement, a transparent oxide layer (SiO2) is sandwiched between two laser absorbing layers (Ni) in a single, cohesive sample. These samples were mass manufactured (>105 samples) using a combination of physical vapor deposition, photolithography, wet etching, and plasma etching. The double hot-plate arrangement coupled with the chemical and spatial homogeneity of the laser absorbing layers addresses problems caused by mixtures of transparent and opaque samples. The controlled-geometry samples have dimensions of 50 μm x 50 μm x 1.4 μm. The dimensions of the samples are much larger than the synchrotron x-ray beam. With a heating laser FWHM of ~50 μm, the radial temperature gradients within the volume probed by the x-ray are reduced. We conducted XRD experiments to P > 50 GPa and T > 2200 K at beamline 16-ID-B (HPCAT) of the Advanced Photon Source. Here we present relevant thermal modeling of the LHDAC environment along with Ni and SiO2 P-V-T equations of state. Our photolithography method of sample fabrication can be extended to different materials including but not limited to Fe and MgO.
NASA Astrophysics Data System (ADS)
Masocha, Willias; Kombian, Samuel B.; Edafiogho, Ivan O.
2016-02-01
Recently, we found that methyl 4-(4‧-bromophenyl)aminocyclohex-3-en-6-methyl-2-oxo-1-oate (E139), an anticonvulsant enaminone, has antinociceptive activity in the hot plate test. In this study we evaluated the antinociceptive activity of five anilino enaminones E139, ethyl 4-(4‧-chlorophenyl)amino-6-methyl-2-oxocyclohex-3-en-1-oate (E121), ethyl 4-(4‧-bromophenyl)amino-6-methyl-2-oxocyclohex-3-en-1-oate (E122), methyl 4-(4‧-chlorophenyl)amino-6-methyl-2-oxocyclohex-3-en-1-oate (E138) and ethyl 4-(4‧-fluorophenyl)amino-6-methyl-2-oxocyclohex-3-en-1-oate (BRG 19) using the formalin and hot plate tests. E139 has been reported to exert its effects via enhancement of extracellular GABA levels, thus tiagabine, a GABA transporter inhibitor, was evaluated as a control together with indomethacin. Tiagabine had antinociceptive activity in both phase 1 (neurogenic pain) and phase 2 (inflammatory pain) of the formalin test, whereas indomethacin had activity only in phase 2. E139 and E138 had antinociceptive activity in both phases of the formalin test, whereas E121 had activity only in phase 1 and BRG 19 had activity only in phase 2. E122 had no significant activity in either phase. In the hot plate test only E139 had antinociceptive activity. Administration of either bicuculline, a GABAA receptor antagonist, or CGP 35348, a GABAB receptor antagonist, blocked the antinociceptive activity of E139. In conclusion our results indicate that E139 has antinociceptive activity in the formalin and hot plate tests that are dependent on GABA receptors.
Hot-pressed production and laser properties of ZnSe:Fe2+
NASA Astrophysics Data System (ADS)
Avetisov, R. I.; Balabanov, S. S.; Firsov, K. N.; Gavrishchuk, E. M.; Gladilin, A. A.; Ikonnikov, V. B.; Kalinushkin, V. P.; Kazantsev, S. Yu.; Kononov, I. G.; Zykova, M. P.; Mozhevitina, E. N.; Khomyakov, A. V.; Savin, D. V.; Timofeeva, N. A.; Uvarov, O. V.; Avetissov, I. Ch.
2018-06-01
A new approach for fabrication of laser elements in form of plates based on ZnSe:Fe2+ with undoped faces, combining the advantages of hot pressing and diffusion techniques has been proposed. CVD-ZnSe was used as a host material. 1 μm Fe film was deposited by electron-beam technique on one side of the polished CVD-ZnSe plate (20 mm in diameter and 2 mm in thickness). The elements were stacked in contact by iron surfaces, placed in a hot press-mold die, heated under vacuum to 1000 °C, exposed during 60 min with the application of 25 MPa uniaxial pressure. The iron film was dissolved in ZnSe matrix and elements welded together. The samples were subjected to hot isostatic pressing (HIP) during 29 h at 100 MPa argon pressure and 1300 °C. The influence of sintering and HIP processing conditions on local morphology and properties of the interface of welded elements was studied by SEM, TEM and optical microscopy. For all composite elements the lasing was obtained at a pumping by HF-laser at RT with high efficiency around 40%. The proposed technique removes restrictions on the size of laser elements and appears to be very promising for the management of the distribution profile of the doping component.
Multiscale modelling and experimentation of hydrogen embrittlement in aerospace materials
NASA Astrophysics Data System (ADS)
Jothi, Sathiskumar
Pulse plated nickel and nickel based superalloys have been used extensively in the Ariane 5 space launcher engines. Large structural Ariane 5 space launcher engine components such as combustion chambers with complex microstructures have usually been manufactured using electrodeposited nickel with advanced pulse plating techniques with smaller parts made of nickel based superalloys joined or welded to the structure to fabricate Ariane 5 space launcher engines. One of the major challenges in manufacturing these space launcher components using newly developed materials is a fundamental understanding of how different materials and microstructures react with hydrogen during welding which can lead to hydrogen induced cracking. The main objective of this research has been to examine and interpret the effects of microstructure on hydrogen diffusion and hydrogen embrittlement in (i) nickel based superalloy 718, (ii) established and (iii) newly developed grades of pulse plated nickel used in the Ariane 5 space launcher engine combustion chamber. Also, the effect of microstructures on hydrogen induced hot and cold cracking and weldability of three different grades of pulse plated nickel were investigated. Multiscale modelling and experimental methods have been used throughout. The effect of microstructure on hydrogen embrittlement was explored using an original multiscale numerical model (exploiting synthetic and real microstructures) and a wide range of material characterization techniques including scanning electron microscopy, 2D and 3D electron back scattering diffraction, in-situ and ex-situ hydrogen charged slow strain rate tests, thermal spectroscopy analysis and the Varestraint weldability test. This research shows that combined multiscale modelling and experimentation is required for a fundamental understanding of microstructural effects in hydrogen embrittlement in these materials. Methods to control the susceptibility to hydrogen induced hot and cold cracking and to improve the resistance to hydrogen embrittlement in aerospace materials are also suggested. This knowledge can play an important role in the development of new hydrogen embrittlement resistant materials. A novel micro/macro-scale coupled finite element method incorporating multi-scale experimental data is presented with which it is possible to perform full scale component analyses in order to investigate hydrogen embrittlement at the design stage. Finally, some preliminary and very encouraging results of grain boundary engineering based techniques to develop alloys that are resistant to hydrogen induced failure are presented. Keywords: Hydrogen embrittlement; Aerospace materials; Ariane 5 combustion chamber; Pulse plated nickel; Nickel based super alloy 718; SSRT test; Weldability test; TDA; SEM/EBSD; Hydrogen induced hot and cold cracking; Multiscale modelling and experimental methods.
Method of forming oxide coatings. [for solar collector heating panels
NASA Technical Reports Server (NTRS)
Mcdonald, G. E. (Inventor)
1983-01-01
This invention is concerned with an improved plating process for covering a substrate with a black metal oxide film. The invention is particularly directed to making a heating panel for a solar collector. A compound is electrodeposited from an aqueous solution containing cobalt metal salts onto a metal substrate. This compound is converted during plating into a black, highly absorbing oxide coating which contains hydrated oxides. This is achieved by the inclusion of an oxidizing agent in the plating bath. The inclusion of an oxidizing agent in the plating bath is contrary to standard electroplating practice. The hydrated oxides are converted to oxides by treatment in a hot bath, such as boiling water. An oxidizing agent may be added to the hot liquid treating bath.
An experimental investigation with artificial sunlight of a solar hot-water heater
NASA Technical Reports Server (NTRS)
Simon, F. F.
1976-01-01
Thermal performance measurements were made of a commercial solar hot-water heater in a solar simulator. The objective of the test was to determine basic performance characteristics of a traditional type of flat-plate collector, with and without side reflectors (to increase the solar flux). Due to the fact that collector testing in the solar simulator permits control of the variables that affect collector performance, it was possible to obtain information on each of the following: (1) the effect of flow and incidence angle on the efficiency of a flat-plate collector (but only without side reflectors), (2) transient performance under flow and nonflow conditions, (3) the effectiveness of reflectors in increasing collector efficiency for a zero radiation angle at fluid temperatures required for solar air conditioning, and (4) the limits of applicability of a collector efficiency correlation based on the Hottel-Whillier equation (1958).
Vartoukian, Sonia R; Adamowska, Aleksandra; Lawlor, Megan; Moazzez, Rebecca; Dewhirst, Floyd E; Wade, William G
2016-01-01
Over a third of oral bacteria are as-yet-uncultivated in-vitro. Siderophores have been previously shown to enable in-vitro growth of previously uncultivated bacteria. The objective of this study was to cultivate novel oral bacteria in siderophore-supplemented culture media. Various compounds with siderophore activity, including pyoverdines-Fe-complex, desferricoprogen and salicylic acid, were found to stimulate the growth of difficult-to-culture strains Prevotella sp. HOT-376 and Fretibacterium fastidiosum. Furthermore, pyrosequencing analysis demonstrated increased proportions of the as-yet-uncultivated phylotypes Dialister sp. HOT-119 and Megasphaera sp. HOT-123 on mixed culture plates supplemented with siderophores. Therefore a culture model was developed, which incorporated 15 μg siderophore (pyoverdines-Fe-complex or desferricoprogen) or 150 μl neat subgingival-plaque suspension into a central well on agar plates that were inoculated with heavily-diluted subgingival-plaque samples from subjects with periodontitis. Colonies showing satellitism were passaged onto fresh plates in co-culture with selected helper strains. Five novel strains, representatives of three previously-uncultivated taxa (Anaerolineae bacterium HOT-439, the first oral taxon from the Chloroflexi phylum to have been cultivated; Bacteroidetes bacterium HOT-365; and Peptostreptococcaceae bacterium HOT-091) were successfully isolated. All novel isolates required helper strains for growth, implying dependence on a biofilm lifestyle. Their characterisation will further our understanding of the human oral microbiome.
Electrical Characterization of Spherical Copper Oxide Memristive Array Sensors
2014-03-27
Quartz Tube Furnace . . . . . . . 37 3.3.2.2 Thermal Oxidation in Air on a Hot Plate . . . . . . . . . 38 3.4 Experimental Setup for Electrical...closed hot plate . . . 80 B.1 Oxidation rates for copper at 100 °C by two different formulas . . . . . . . . . 81 xi List of Tables Table Page 2.1 The... Tectonics Inc. and manufactured by Canfield Technologies using a proprietary fabrication method. As received, the copper spheres may have contaminants
NASA Astrophysics Data System (ADS)
Gates, W. G.
1982-05-01
Bendix product applications require the capability of fabricating heavy gage, high strength materials. Five commercial sources have been identified that have the capability of spin forming metal thicknesses greater than 9.5 mm and four equipment manufacturers produce machines with this capability. Twelve assemblies selected as candidates for spin forming applications require spin forming of titanium, 250 maraging steel, 17-4 pH stainless steel, Nitronic 40 steel, 304 L stainless steel, and 6061 aluminum. Twelve parts have been cold spin formed from a 250 maraging steel 8.1 mm wall thickness machine preform, and six have been hot spin formed directly from 31.8-mm-thick flat plate. Thirty-three Ti-6Al-4V titanium alloy parts and 26 17-4 pH stainless steel parts have been hot spin formed directly from 31.8-mm-thick plate. Hot spin forming directly from plate has demonstrated the feasibility and favorable economics of this fabrication technique for Bendix applications.
Efficacy of Common Analgesics for Postsurgical Pain in Rats
Waite, Megan E; Tomkovich, Ashleigh; Quinn, Tammie L; Schumann, Alan P; Dewberry, L Savannah; Totsch, Stacie K; Sorge, Robert E
2015-01-01
Each year, millions of rats undergo surgery for research purposes and receive analgesics to alleviate pain. We sought to evaluate the efficacy of common analgesics in tests of hot-plate nociception and postsurgical pain by using the Rat Grimace Scale. Rats received a single dose of one of several drug–dose combinations and were tested by using the hot-plate test (acute pain) or after laparotomy (with either prophylactic or intraoperative analgesic). The efficacy of analgesics for hot-plate pain was generally not predictive of efficacy for surgical pain. Carprofen and ketoprofen were rarely effective in any of the conditions tested. With the exception of the opioid buprenorphine, several of the drugs we tested required higher-than-recommended doses to alleviate pain. Taken together, our data suggest that current analgesic use frequently is insufficient, and many rats may experience significant postsurgical pain even when analgesics are used in commonly recommended doses. PMID:26224443
Automated analysis of hot spot X-ray images at the National Ignition Facility
NASA Astrophysics Data System (ADS)
Khan, S. F.; Izumi, N.; Glenn, S.; Tommasini, R.; Benedetti, L. R.; Ma, T.; Pak, A.; Kyrala, G. A.; Springer, P.; Bradley, D. K.; Town, R. P. J.
2016-11-01
At the National Ignition Facility, the symmetry of the hot spot of imploding capsules is diagnosed by imaging the emitted x-rays using gated cameras and image plates. The symmetry of an implosion is an important factor in the yield generated from the resulting fusion process. The x-ray images are analyzed by decomposing the image intensity contours into Fourier and Legendre modes. This paper focuses on the additional protocols for the time-integrated shape analysis from image plates. For implosions with temperatures above ˜4 keV, the hard x-ray background can be utilized to infer the temperature of the hot spot.
Automated analysis of hot spot X-ray images at the National Ignition Facility
Khan, S. F.; Izumi, N.; Glenn, S.; ...
2016-09-02
At the National Ignition Facility, the symmetry of the hot spot of imploding capsules is diagnosed by imaging the emitted x-rays using gated cameras and image plates. The symmetry of an implosion is an important factor in the yield generated from the resulting fusion process. The x-ray images are analyzed by decomposing the image intensity contours into Fourier and Legendre modes. This paper focuses on the additional protocols for the time-integrated shape analysis from image plates. Here, for implosions with temperatures above ~4keV, the hard x-ray background can be utilized to infer the temperature of the hot spot.
Automated analysis of hot spot X-ray images at the National Ignition Facility
DOE Office of Scientific and Technical Information (OSTI.GOV)
Khan, S. F., E-mail: khan9@llnl.gov; Izumi, N.; Glenn, S.
At the National Ignition Facility, the symmetry of the hot spot of imploding capsules is diagnosed by imaging the emitted x-rays using gated cameras and image plates. The symmetry of an implosion is an important factor in the yield generated from the resulting fusion process. The x-ray images are analyzed by decomposing the image intensity contours into Fourier and Legendre modes. This paper focuses on the additional protocols for the time-integrated shape analysis from image plates. For implosions with temperatures above ∼4 keV, the hard x-ray background can be utilized to infer the temperature of the hot spot.
Automated analysis of hot spot X-ray images at the National Ignition Facility.
Khan, S F; Izumi, N; Glenn, S; Tommasini, R; Benedetti, L R; Ma, T; Pak, A; Kyrala, G A; Springer, P; Bradley, D K; Town, R P J
2016-11-01
At the National Ignition Facility, the symmetry of the hot spot of imploding capsules is diagnosed by imaging the emitted x-rays using gated cameras and image plates. The symmetry of an implosion is an important factor in the yield generated from the resulting fusion process. The x-ray images are analyzed by decomposing the image intensity contours into Fourier and Legendre modes. This paper focuses on the additional protocols for the time-integrated shape analysis from image plates. For implosions with temperatures above ∼4 keV, the hard x-ray background can be utilized to infer the temperature of the hot spot.
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
This Preliminary Report is prepared to study the facilities required for recycling contaminated stainless steel scrap into plate which will be fabricated into boxes suitable for the storage of contaminated wastes and rubble. The study is based upon the underlying premise that the most cost effective way to produce stainless steel is to use the same processes employed by companies now in production of high quality stainless steel. Therefore, the method selected for this study for the production of stainless steel plate from scrap is conventional process using an Electric Arc Furnace for meltdown to hot metal, a Continuous Castermore » for production of cast slabs, and a Reversing Hot Mill for rolling the slabs into plate. The fabrication of boxes from the plate utilizes standard Shears, Punch Presses and welding equipment with Robotic Manipulators. This Study presumes that all process fumes, building dusts and vapors will be cycled through a baghouse and a nuclear grade HEPA filter facility prior to discharge. Also, all process waste water will be evaporated into the hot flue gas stream from the furnace utilizing a quench tank; so there will be no liquid discharges from the facility and all vapors will be processed through a HEPA filter. Even though HEPA filters are used today in controlling radioactive contamination from nuclear facilities there is a sparsity of data concerning radioactivity levels and composition of waste that may be collected from contaminated scrap steel processing. This report suggests some solutions to these problems but it is recommended that additional study must be given to these environmental problems.« less
Method of fabricating a uranium-bearing foil
Gooch, Jackie G [Seymour, TN; DeMint, Amy L [Kingston, TN
2012-04-24
Methods of fabricating a uranium-bearing foil are described. The foil may be substantially pure uranium, or may be a uranium alloy such as a uranium-molybdenum alloy. The method typically includes a series of hot rolling operations on a cast plate material to form a thin sheet. These hot rolling operations are typically performed using a process where each pass reduces the thickness of the plate by a substantially constant percentage. The sheet is typically then annealed and then cooled. The process typically concludes with a series of cold rolling passes where each pass reduces the thickness of the plate by a substantially constant thickness amount to form the foil.
Cheng, Chin-Chi; Yang, Sen-Yeu; Lee, Dasheng
2014-01-01
This paper presents an integrated high temperature ultrasonic transducer (HTUT) on a sensor insert and its application for real-time diagnostics of the conventional hot embossing process to fabricate V-cut patterns. The sensor was directly deposited onto the sensor insert of the hot embossing mold by using a sol-gel spray technique. It could operate at temperatures higher than 400 °C and uses an ultrasonic pulse-echo technique. The ultrasonic velocity could indicate the three statuses of the hot embossing process and also evaluate the replication of V-cut patterns on a plastic plate under various processing conditions. The progression of the process, including mold closure, plastic plate softening, cooling and plate detachment inside the mold, was clearly observed using ultrasound. For an ultrasonic velocity range from 2197.4 to 2435.9 m/s, the height of the V-cut pattern decreased from 23.0 to 3.2 μm linearly, with a ratio of −0.078 μm/(m/s). The incompleteness of the replication of the V-cut patterns could be indirectly observed by the ultrasonic signals. This study demonstrates the effectiveness of the ultrasonic sensors and technology for diagnosing the replicating condition of microstructures during the conventional hot embossing process. PMID:25330051
Sadigh, Parviz Lionel; Chang, Li-Ren; Feng, Kuan-Ming; Jeng, Seng-Feng
2014-09-01
Bioabsorbable plates developed for use in the facial skeleton have become an integral part of the craniomaxillofacial surgeon's reconstructive armamentarium. They avoid the problems associated with the retention of metal plates and can be easily contoured when heated in a thermobath. The technical process of molding and securing these devices, often through small access incisions, to achieve rigid fixation of facial fractures can be difficult. In this article, we describe a simple, novel technique that we have developed, using hot water suction irrigation, to achieve in situ molding of resorbable plates during facial fracture fixation. We used this technique to fix 123 facial fractures in 110 patients over a 4-year period. No complications secondary to the use of hot water suction irrigation were encountered.
NASA Astrophysics Data System (ADS)
Zhang, Wencong; Zhang, Lingjia; Feng, Yangju; Cui, Guorong; Chen, Wenzhen
2018-04-01
Plates of 2.5 vol. % TiB whisker-reinforced Ti6Al4V titanium matrix composites (TiBw/Ti64) with network structure were successfully fabricated by hot-hydrostatic extrusion with steel cup at 1100 °C. The dimensions of plates were about 150mm in length, 27mm in width and 2mm in thickness. After extrusion, the original equiaxed-network structure formed by TiB whiskers still existed, but was compressed in cross-section and stretched in longitudinal section and then the TiB whiskers were directional distribution along the extrusion direction. Furthermore, the mechanical properties results showed that the strength, hardness and ductility of the plates were significantly improved compared to as-sintered composites.
NASA Technical Reports Server (NTRS)
Kim, K.; Wiedner, B.; Camci, C.
1993-01-01
A combined convective heat transfer and fluid dynamics investigation in a turbulent round jet impinging on a flat surface is presented. The experimental study uses a high resolution liquid crystal technique for the determination of the convective heat transfer coefficients on the impingement plate. The heat transfer experiments are performed using a transient heat transfer method. The mean flow and the character of turbulent flow in the free jet is presented through five hole probe and hot wire measurements, respectively. The flow field character of the region near the impingement plate plays an important role in the amount of convective heat transfer. Detailed surveys obtained from five hole probe and hot wire measurements are provided. An extensive validation of the liquid crystal based heat transfer method against a conventional technique is also presented. After a complete documentation of the mean and turbulent flow field, the convective heat transfer coefficient distributions on the impingement plate are presented. The near wall of the impingement plate and the free jet region is treated separately. The current heat transfer distributions are compared to other studies available from the literature. The present paper contains complete sets of information on the three dimensional mean flow, turbulent velocity fluctuations, and convective heat transfer to the plate. The experiments also prove that the present nonintrusive heat transfer method is highly effective in obtaining high resolution heat transfer maps with a heat transfer coefficient uncertainty of 5.7 percent.
NASA Astrophysics Data System (ADS)
Larzabal, G.; Isasti, N.; Rodriguez-Ibabe, J. M.; Uranga, P.
2018-03-01
The use of microalloyed steels in the production of thick plates is expanding due to the possibility of achieving attractive combinations of strength and toughness. As market requirements for high strength plates are increasing and new applications require reduced weight and innovative designs, novel approaches to attaining cost-effective grades are being developed. The mechanism of precipitation strengthening has been widely used in thin strip products, since the optimization of the coiling strategy offers interesting combinations in terms of final properties and microalloying additions. Precipitation strengthening in thick plates, however, is less widespread due to the limitation of interphase precipitation during continuous cooling after hot rolling. With the main objective of exploring the limits of this strengthening mechanism, laboratory thermomechanical simulations that reproduced plate hot rolling mill conditions were performed using low carbon steels microalloyed with Nb, NbMo, and TiMo additions. After continuous cooling to room temperature, a set of heat treatments using fast heating rates were applied simulating the conditions of induction heat treatments. An important increase of both yield and tensile strengths was measured after induction treatment without any important impairment in toughness properties. A significant precipitation hardening is observed in Mo-containing grades under specific heat treatment parameters.
Droplet Evaporator For High-Capacity Heat Transfer
NASA Technical Reports Server (NTRS)
Valenzuela, Javier A.
1993-01-01
Proposed heat-exchange scheme boosts heat transfer per unit area. Key component is generator that fires uniform size droplets of subcooled liquid at hot plate. On impact, droplets spread out and evaporate almost instantly, removing heat from plate. In practice, many generator nozzles arrayed over evaporator plate.
NASA Technical Reports Server (NTRS)
Brazel, J. P.; Kennedy, B. S.
1974-01-01
The materials studied are described along with the apparatus and the experimental techniques employed. The results of the measurements involving two REI Silica materials and a Mod 1 B REI Mullite are listed in a table. Measurements were conducted at unusually high temperature differences to detect 'shine-through' radiation transparency. Photographs are presented of the high-temperature guarded hot plate assembly.
Influence of oxcarbazepine on the antinociceptive action of morphine and metamizole in mice.
Pakulska, Wanda; Czarnecka, Elzbieta
2009-01-01
Numerous methods of management applied in order to obtain higher therapeutic efficacy of drugs with minimum adverse effects include taking advantage of interactions taking place between individual agents. Analgesics are combined with drugs belonging to other therapeutic groups, including, more and more frequently, antiepileptic agents. The influence of oxcarbazepine (10 mg/kg) on the antinociceptive effect of morphine (10 mg/kg) and metamizole (500 mg/kg) was investigated in mice using the hot-plate and tail-flick tests. All drugs were injected intraperitoneally (i.p.). Oxcarbazepine was administered 30 min prior to the injection of analgesic drugs. The reactions to noxious stimuli were measured 30, 60 and 90 min after the administration of an analgesic. The study was further conducted for 10 days with repeated drug doses. Single administration of oxcarbazepine enhanced the antinociceptive effect of a single dose of morphine, and 10-day administration led to a decrease of morphine tolerance in the hot-plate test. Oxcarbazepine administered in a single dose did not affect significantly the antinociceptive effect of metamizole in either of the tests. Multiple administration of oxcarbazepine enhanced the antinociceptive effect of metamizole in the hot-plate test. Oxcarbazepine alone, administered in a single and repeated doses, demonstrated an antinociceptive effect, but only for the hot-plate test, which indicates involvement of supraspinal structures in antinociception.
NASA Astrophysics Data System (ADS)
Joseph, Joby; Muthukumaran, S.; Pandey, K. S.
2016-01-01
Present investigation is an attempt to study the weldability characteristics of sintered hot-forged plates of AISI 4135 steel produced through powder metallurgy (P/M) route using matching filler materials of ER80S B2. Compacts of homogeneously blended elemental powders corresponding to the above steel were prepared on a universal testing machine (UTM) by taking pre-weighed powder blend with a suitable die, punch and bottom insert assembly. Indigenously developed ceramic coating was applied on the entire surface of the compacts in order to protect them from oxidation during sintering. Sintered preforms were hot forged to flat, approximately rectangular plates, welded by pulsed current gas tungsten arc welding (PCGTAW) processes with aforementioned filler materials. Microstructural, tensile and hardness evaluations revealed that PCGTAW process with low heat input could produce weldments of good quality with almost nil defects. It was established that PCGTAW joints possess improved tensile properties compared to the base metal and it was mainly attributed to lower heat input, resulting in finer fusion zone grains and higher fusion zone hardness. Thus, the present investigation opens a new and demanding field in research.
Effect of an Auxiliary Plate on Passive Heat Dissipation of Carbon Nanotube-Based Materials.
Yu, Wei; Duan, Zheng; Zhang, Guang; Liu, Changhong; Fan, Shoushan
2018-03-14
Carbon nanotubes (CNTs) and other related CNT-based materials with a high thermal conductivity can be used as promising heat dissipation materials. Meanwhile, the miniaturization and high functionality of portable electronics, such as laptops and mobile phones, are achieved at the cost of overheating the high power-density components. The heat removal for hot spots occurring in a relatively narrow space requires simple and effective cooling methods. Here, an auxiliary passive cooling approach by the aid of a flat plate (aluminum-magnesium alloy) is investigated to accommodate heat dissipation in a narrow space. The cooling efficiency can be raised to 43.5%. The cooling performance of several CNT-based samples is compared under such circumstances. Heat dissipation analyses show that, when there is a nearby plate for cooling assistance, the heat radiation is weakened and natural convection is largely improved. Thus, improving heat radiation by increasing emissivity without reducing natural convection can effectively enhance the cooling performance. Moreover, the decoration of an auxiliary cooling plate with sprayed CNTs can further improve the cooling performance of the entire setup.
An investigation of the flow characteristics in the blade endwall corner region
NASA Technical Reports Server (NTRS)
Hazarika, Birinchi K.; Raj, Rishi S.
1987-01-01
Studies were undertaken to determine the structure of the flow in the blade end wall corner region simulated by attaching two uncambered airfoils on either side of a flat plate with a semicircular leading edge. Detailed measurements of the corner flow were obtained with conventional pressure probes, hot wire anemometry, and flow visualization. The mean velocity profiles and six components of the Reynolds stress tensor were obtained with an inclined single sensor hot wire probe whereas power spectra were obtained with a single sensor oriented normal to the flow. Three streamwise vortices were identified based on the surface streamlines, distortion of total pressure profiles, and variation of mean velocity components in the corner. A horseshoe vortex formed near the leading edge of the airfoil. Within a short distance downstream, a corner vortex was detected between the horseshoe vortex and the surfaces forming the corner. A third vortex was formed at the rear portion of the corner between the corner vortex and the surface of the flat plate. Turbulent shear stress and production of turbulence are negligibly small. A region of negative turbulent shear stress was also observed near the region of low turbulence intensity from the vicinity of the flat plate.
Thermal conductivity of metals
NASA Technical Reports Server (NTRS)
Kazem, Sayyed M.
1990-01-01
The objective is to familiarize students with steady and unsteady heat transfer by conduction and with the effect of thermal conductivity upon temperature distribution through a homogeneous substance. The elementary heat conduction experiment presented is designed for associate degree technology students in a simple manner to enhance their intuition and to clarify many confusing concepts such as temperature, thermal energy, thermal conductivity, heat, transient and steady flows. The equipment set is safe, small, portable (10 kg) and relatively cheap (about $1200): the electric hot plate 2 kg (4.4 lb) for $175: the 24 channel selector and Thermocouple Digital Readout (Trendicator) 4.5 kg (10 lb) for about $1000; the three metal specimens (each of 2.5 cm diameter and 11 cm length), base plate and the bucket all about 3 kg (7 lb) for about $25. The experiment may take from 60 to 70 minutes. Although the hot plate surface temperature could be set from 90 to 370 C (maximum of 750 watts) it is a good practice to work with temperatures of 180 to 200 C (about 400 watts). They may experiment in squads of 2, 3 or even 4, or the instructor may demonstrate it for the whole class.
On the Prediction of Hot Tearing in Al-to-Steel Welding by Friction Melt Bonding
NASA Astrophysics Data System (ADS)
Jimenez-Mena, N.; Jacques, P. J.; Drezet, J. M.; Simar, A.
2018-07-01
Aluminum alloy AA6061 was welded to dual-phase steel 980 (DP980) by the friction melt bonding (FMB) process. Hot tears have been suppressed by controlling the thermomechanical cycle. In particular, the welding speed and the thermal conductivity of the backing plate have been optimized. A finite-element thermomechanical model coupled with the Rappaz-Drezet-Gremaud (RDG) criterion has been used to explain these experimental observations. The hot tear susceptibility has been reduced with large thermal gradients and with the formation of a cellular microstructure. Both effects are favored by a backing plate made of a material with high thermal conductivity, such as copper.
On the Prediction of Hot Tearing in Al-to-Steel Welding by Friction Melt Bonding
NASA Astrophysics Data System (ADS)
Jimenez-Mena, N.; Jacques, P. J.; Drezet, J. M.; Simar, A.
2018-04-01
Aluminum alloy AA6061 was welded to dual-phase steel 980 (DP980) by the friction melt bonding (FMB) process. Hot tears have been suppressed by controlling the thermomechanical cycle. In particular, the welding speed and the thermal conductivity of the backing plate have been optimized. A finite-element thermomechanical model coupled with the Rappaz-Drezet-Gremaud (RDG) criterion has been used to explain these experimental observations. The hot tear susceptibility has been reduced with large thermal gradients and with the formation of a cellular microstructure. Both effects are favored by a backing plate made of a material with high thermal conductivity, such as copper.
Safety for Older Consumers: Home Safety Checklist
... 3 Keep ashtrays, smoking materi- als, candles, hot plates and other potential fire sources away from curtains, ... A ll electrical outlets and switches have cover plates installed so no wiring is exposed. U nused ...
Indirect ignition of energetic materials with laser-driven flyer plates.
Dean, Steven W; De Lucia, Frank C; Gottfried, Jennifer L
2017-01-20
The impact of laser-driven flyer plates on energetic materials CL-20, PETN, and TATB has been investigated. Flyer plates composed of 25 μm thick Al were impacted into the energetic materials at velocities up to 1.3 km/s. The flyer plates were accelerated by means of an Nd:YAG laser pulse. The laser pulse generates rapidly expanding plasma between the flyer plate foil and the substrate to which it is adhered. As the plasma grows, a section of the metal foil is ejected at high speed, forming the flyer plate. The velocity of the flyer plate was determined using VISAR, time of flight, and high-speed video. The response of the energetic material to impact was determined by light emission recorded by an infrared-sensitive photodiode. Following post-impact analysis of the impacted energetic material, it was hypothesized that the light emitted by the material after impact is not due to the impact of the flyer itself but rather is caused by the decomposition of energetic material ejected (via the shock of flyer plate impact) into a cloud of hot products generated during the launch of the flyer plate. This hypothesis was confirmed through schlieren imaging of a flyer plate launch, clearly showing the ejection of hot gases and particles from the region surrounding the flyer plate launch and the burning of the ejected energetic material particles.
Hot hollow cathode gun assembly
Zeren, J.D.
1983-11-22
A hot hollow cathode deposition gun assembly includes a hollow body having a cylindrical outer surface and an end plate for holding an adjustable heat sink, the hot hollow cathode gun, two magnets for steering the plasma from the gun into a crucible on the heat sink, and a shutter for selectively covering and uncovering the crucible.
Motel solar-hot-water system with nonpressurized storage--Jacksonville, Florida
NASA Technical Reports Server (NTRS)
1981-01-01
Modular roof-mounted copper-plated arrays collect solar energy; heated water drains from them into 1,000 gallon nonpressurized storage tank which supplies energy to existing pressurized motel hot water lines. System provides 65 percent of hot water demand. Report described systems parts and operation, maintenance, and performance and provides warranty information.
Fabrication of Monolithic RERTR Fuels by Hot Isostatic Pressing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jan-Fong Jue; Blair H. Park; Curtis R. Clark
2010-11-01
The RERTR (Reduced Enrichment for Research and Test Reactors) Program is developing advanced nuclear fuels for high-power test reactors. Monolithic fuel design provides higher uranium loading than that of the traditional dispersion fuel design. Hot isostatic pressing is a promising process for low-cost batch fabrication of monolithic RERTR fuel plates for these high-power reactors. Bonding U Mo fuel foil and 6061 Al cladding by hot isostatic press bonding was successfully developed at Idaho National Laboratory. Due to the relatively high processing temperature, the interaction between fuel meat and aluminum cladding is a concern. Two different methods were employed to mitigatemore » this effect: (1) a diffusion barrier and (2) a doping addition to the interface. Both types of fuel plates have been fabricated by hot isostatic press bonding. Preliminary results show that the direct fuel/cladding interaction during the bonding process was eliminated by introducing a thin zirconium diffusion barrier layer between the fuel and the cladding. Fuel plates were also produced and characterized with a silicon-rich interlayer between fuel and cladding. This paper reports the recent progress of this developmental effort and identifies the areas that need further attention.« less
Irradiated microstructure of U-10Mo monolithic fuel plate at very high fission density
NASA Astrophysics Data System (ADS)
Gan, J.; Miller, B. D.; Keiser, D. D.; Jue, J. F.; Madden, J. W.; Robinson, A. B.; Ozaltun, H.; Moore, G.; Meyer, M. K.
2017-08-01
Monolithic U-10Mo alloy fuel plates with Al-6061 cladding are being developed for use in research and test reactors as low enrichment fuel (<20% U-235 enrichment) as a result of its high uranium loading capacity compared to that of U-7Mo dispersion fuel. These fuel plates contain a Zr diffusion barrier between the U-10Mo fuel and Al-6061 cladding that suppresses the interaction between the U-Mo fuel foil and Al alloy cladding that is known to be problematic under irradiation. Different methods have been employed to fabricate monolithic fuel plates, including hot-rolling with no cold-rolling. L1P09T is a hot-rolled fuel plate irradiated to high fission density in the RERTR-9B experiment. This paper discusses the TEM characterization results for this U-10Mo/Zr/Al6061 monolithic fuel plate (∼59% U-235 enrichment) irradiated in Advanced Test Reactor at Idaho National Laboratory with an unprecedented high local fission density of 9.8E+21 fissions/cm3. The calculated fuel foil centerline temperature at the beginning of life and the end of life is 141 and 194 °C, respectively. TEM lamellas were prepared using focus ion beam lift-out technique. The estimated U-Mo fuel swelling, based on the fuel foil thickness change from SEM, is approximately 76%. Large bubbles (>1 μm) are distributed evenly in U-Mo and interlink of these bubbles is evident. The average size of subdivided grains at this fission density appears similar to that at 5.2E+21 fissions/cm3. The measured average Mo and Zr content in the fuel matrix is ∼30 at% and ∼7 at%, respectively, in general agreement with the calculated Mo and Zr from fission density.
Investigation of Methods for Selectively Reinforcing Aluminum and Aluminum-Lithium Materials
NASA Technical Reports Server (NTRS)
Bird, R. Keith; Alexa, Joel A.; Messick, Peter L.; Domack, Marcia S.; Wagner, John A.
2013-01-01
Several studies have indicated that selective reinforcement offers the potential to significantly improve the performance of metallic structures for aerospace applications. Applying high-strength, high-stiffness fibers to the high-stress regions of aluminum-based structures can increase the structural load-carrying capability and inhibit fatigue crack initiation and growth. This paper discusses an investigation into potential methods for applying reinforcing fibers onto the surface of aluminum and aluminum-lithium plate. Commercially-available alumina-fiber reinforced aluminum alloy tapes were used as the reinforcing material. Vacuum hot pressing was used to bond the reinforcing tape to aluminum alloy 2219 and aluminum-lithium alloy 2195 base plates. Static and cyclic three-point bend testing and metallurgical analysis were used to evaluate the enhancement of mechanical performance and the integrity of the bond between the tape and the base plate. The tests demonstrated an increase in specific bending stiffness. In addition, no issues with debonding of the reinforcing tape from the base plate during bend testing were observed. The increase in specific stiffness indicates that selectively-reinforced structures could be designed with the same performance capabilities as a conventional unreinforced structure but with lower mass.
Method and apparatus for measuring thermal conductivity of small, highly insulating specimens
NASA Technical Reports Server (NTRS)
Miller, Robert A. (Inventor); Kuczmarski, Maria A. (Inventor)
2012-01-01
A hot plate method and apparatus for the measurement of thermal conductivity combines the following capabilities: 1) measurements of very small specimens; 2) measurements of specimens with thermal conductivity on the same order of that as air; and, 3) the ability to use air as a reference material. Care is taken to ensure that the heat flow through the test specimen is essentially one-dimensional. No attempt is made to use heated guards to minimize the flow of heat from the hot plate to the surroundings. Results indicate that since large correction factors must be applied to account for guard imperfections when specimen dimensions are small, simply measuring and correcting for heat from the heater disc that does not flow into the specimen is preferable. The invention is a hot plate method capable of using air as a standard reference material for the steady-state measurement of the thermal conductivity of very small test samples having thermal conductivity on the order of air.
Archer, T.; Danysz, W.; Jonsson, G.; Minor, B. G.; Post, C.
1986-01-01
The effects of the alpha-adrenoceptor antagonists prazosin, phentolamine and yohimbine upon 5-methoxy-N,N-dimethyltryptamine (5-MeODMT)-induced analgesia were tested in the hot-plate, tail-flick and shock-titration tests of nociception with rats. Intrathecally injected yohimbine and phentolamine blocked or attenuated the analgesia produced by systemic administration of 5-MeODMT in all three nociceptive tests. Intrathecally administered prazosin attenuated the analgesic effects of 5-MeODMT in the hot-plate and tail-flick tests, but not in the shock titration test. Intrathecal yohimbine showed a dose-related lowering of pain thresholds in saline and 5-MeODMT-treated animals. Phentolamine and prazosin produced normal dose-related curves in the hot-plate test and biphasic effects in the shock titration and tail-flick tests. These results demonstrate a functional interaction between alpha 2-adrenoceptors and 5-HT agonist-induced analgesia at a spinal level in rats. PMID:2877697
43 CFR 3275.16 - What standards apply to installing and maintaining meters?
Code of Federal Regulations, 2012 CFR
2012-10-01
...; (2) You must calibrate meters measuring steam or hot water flow with a turbine, vortex, ultrasonics... frequent; and (3) You must calibrate meters measuring steam or hot water flow with an orifice plate...
43 CFR 3275.16 - What standards apply to installing and maintaining meters?
Code of Federal Regulations, 2011 CFR
2011-10-01
...; (2) You must calibrate meters measuring steam or hot water flow with a turbine, vortex, ultrasonics... frequent; and (3) You must calibrate meters measuring steam or hot water flow with an orifice plate...
43 CFR 3275.16 - What standards apply to installing and maintaining meters?
Code of Federal Regulations, 2014 CFR
2014-10-01
...; (2) You must calibrate meters measuring steam or hot water flow with a turbine, vortex, ultrasonics... frequent; and (3) You must calibrate meters measuring steam or hot water flow with an orifice plate...
43 CFR 3275.16 - What standards apply to installing and maintaining meters?
Code of Federal Regulations, 2013 CFR
2013-10-01
...; (2) You must calibrate meters measuring steam or hot water flow with a turbine, vortex, ultrasonics... frequent; and (3) You must calibrate meters measuring steam or hot water flow with an orifice plate...
Theoretical analysis on pulsed microwave heating of pork meat supported on ceramic plate.
Basak, Tanmay; Rao, Badri S
2010-11-01
Theoretical analysis has been carried out to study the role of ceramic plates (alumina and SiC) and pulsed microwave heating of pork meat (Pork Luncheon Roll (PLR) and White Pudding (WP)) samples. Spatial hot spots occur either at the center of the sample or at the outer face or at the face attached with alumina plate and application of pulsing minimizes formation of hot spots within meat samples. Pulsing of microwave is characterized by set point for temperature difference (ΔTS) and on-off constraints for temperature (T'). It is found that alumina plate with higher ΔTS and lower T' may be recommended for thick meat samples (both WP and PLR) whereas for thin meat samples, lower ΔTS with alumina plate/without plate may be preferred. It is also observed that SiC plate may be selectively used with ΔTS=20K for both the pork meats. The distributed microwave incidence is found to be effective due to lesser degree of thermal runaway in absence of pulsing for both meat samples. Copyright © 2010 The American Meat Science Association. Published by Elsevier Ltd. All rights reserved.
Vision-based surface defect inspection for thick steel plates
NASA Astrophysics Data System (ADS)
Yun, Jong Pil; Kim, Dongseob; Kim, KyuHwan; Lee, Sang Jun; Park, Chang Hyun; Kim, Sang Woo
2017-05-01
There are several types of steel products, such as wire rods, cold-rolled coils, hot-rolled coils, thick plates, and electrical sheets. Surface stains on cold-rolled coils are considered defects. However, surface stains on thick plates are not considered defects. A conventional optical structure is composed of a camera and lighting module. A defect inspection system that uses a dual lighting structure to distinguish uneven defects and color changes by surface noise is proposed. In addition, an image processing algorithm that can be used to detect defects is presented in this paper. The algorithm consists of a Gabor filter that detects the switching pattern and employs the binarization method to extract the shape of the defect. The optics module and detection algorithm optimized using a simulator were installed at a real plant, and the experimental results conducted on thick steel plate images obtained from the steel production line show the effectiveness of the proposed method.
Development of a Rolling Process Design Tool for Use in Improving Hot Roll Slab Recovery
DOE Office of Scientific and Technical Information (OSTI.GOV)
Couch, R; Becker, R; Rhee, M
2004-09-24
Lawrence Livermore National Laboratory participated in a U. S. Department of Energy/Office of Industrial Technology sponsored research project 'Development of a Rolling Process Design Tool for Use in Improving Hot Roll Slab Recovery', as a Cooperative Agreement TC-02028 with the Alcoa Technical Center (ATC). The objective of the joint project with Alcoa is to develop a numerical modeling capability to optimize the hot rolling process used to produce aluminum plate. Product lost in the rolling process and subsequent recycling, wastes resources consumed in the energy-intensive steps of remelting and reprocessing the ingot. The modeling capability developed by project partners willmore » be used to produce plate more efficiently and with reduced product loss.« less
Pigott, Jeffrey S.; Ditmer, Derek A.; Fischer, Rebecca A.; ...
2015-11-24
We have fabricated novel controlled-geometry samples for the laser-heated diamond anvil cell (LHDAC) in which a transparent oxide layer (SiO 2) is sandwiched between two laser-absorbing layers (Ni) in a single, cohesive sample. The samples were mass manufactured (>10 4 samples) using a combination of physical vapor deposition, photolithography, and wet and plasma etching. The double hot-plate arrangement of the samples, coupled with the chemical and spatial homogeneity of the laser-absorbing layers, addresses problems of spatial temperature heterogeneities encountered in previous studies where simple mechanical mixtures of transparent and opaque materials were used. Here we report thermal equations of statemore » (EOS) for nickel to 100 GPa and 3000 K and stishovite to 50 GPa and 2400 K obtained using the LHDAC and in situ synchrotron x-ray micro-diffraction. Lastly, we discuss the inner core composition and the stagnation of subducted slabs in the mantle based on our refined thermal EOS.« less
Space Launch System Base Heating Test: Tunable Diode Laser Absorption Spectroscopy
NASA Technical Reports Server (NTRS)
Parker, Ron; Carr, Zak; MacLean, Matthew; Dufrene, Aaron; Mehta, Manish
2016-01-01
This paper describes the Tunable Diode Laser Absorption Spectroscopy (TDLAS) measurement of several water transitions that were interrogated during a hot-fire testing of the Space Launch Systems (SLS) sub-scale vehicle installed in LENS II. The temperature of the recirculating gas flow over the base plate was found to increase with altitude and is consistent with CFD results. It was also observed that the gas above the base plate has significant velocity along the optical path of the sensor at the higher altitudes. The line-by-line analysis of the H2O absorption features must include the effects of the Doppler shift phenomena particularly at high altitude. The TDLAS experimental measurements and the analysis procedure which incorporates the velocity dependent flow will be described.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aikin, Jr., Robert M.
This work describes the experiments and modeling that have been performed to improve and try to optimize the simultaneous casting of three plates of U-10wt%Mo in a single coil vacuum induction melting (VIM) furnace. The plates of interest are 280 mm wide by 203 mm tall by 5 mm thick (11" x 8" x 0.2"). The initial mold design and processing parameters were supplied by Y-12. The mold and casting cavity were instrumented with a number of thermocouples, and the casting performed to determine the thermal history of the mold and casting. The resulting cast plates were radiographed and numerousmore » defects identified. Metallography was performed to help identify the nature of the radiographically observed defects. This information was then used to validate a mold filling and solidification model of that casting. Based on the initial casting, good casting design practice, and process simulation of several design alternatives, a revised design was developed with the goal of minimizing casting defects such as porosity. The redesigned mold had a larger hot-top and had its long axis along the horizontal direction. These changes were to try to develop a strong thermal gradient conducive to good feeding and minimization of micro- and macroporosity in the cast plates. An instrumented casting was then performed with the revised mold design and a linear distributor. This design yielded cast plates with significantly less radiographically identified defects. Unfortunately, there was significant variation in plate weight and metal content in their hot-tops. Fluid flow simulations were then performed on this mold/distributor design. This helped identify the issue with this linear distributor design. Additional simulations were then performed on candidate distributor redesigns and a preferred distributor annular design was identified. This improved annular design was used to produce a third instrumented casting with favorable results. These refined designs and their radiographic characterization are compared to the initial design.« less
Report on the completion of the procurement of the first heat of Alloy 709
DOE Office of Scientific and Technical Information (OSTI.GOV)
Natesan, K.; Zhang, X.; Sham, T. -L.
2017-01-01
This report provides details on the completion of the procurement of the first commercial-sized heat of Alloy 709. The report is a Level 3 deliverable in FY17 (M3AT- 17OR1602053), under the Work Package AT-17OR160205, “Advanced Alloy Development” performed by Oak Ridge National Laboratory, as part of Advanced Structural Materials Program for the Advanced Reactor Technologies (ART). This work project supports the fabrication scale up effort for Alloy 709 that was started in FY16. The effort culminated in the placement of a Purchase Order in August 2016 with a commercial vendor to melt an Alloy 709 heat using industrial melt practice.more » Four ingots, totaling about 45,000 lb, had been bottom-poured from the melt in September 2016. Two of the ingots were hot rolled into 1.2”x60”x155” and 1.1”x60”x100” plates using standard hot rolling process in FY17. Some small test pieces were cut from the asrolled plates and sent to Argonne National Laboratory (ANL) for archival. The plates were then heat treated and surface pickled by the vendor. The plates were subsequently delivered to ANL and Oak Ridge National Laboratory (ORNL). Properties and microstructure screening were performed on these plates upon delivery in February 2017 at ANL. Several samples were cut from the as-rolled and heattreated plates and were analyzed for their microstructures, hardness values, grain sizes, and room temperature tensile properties. The results indicate that the scaled-up heat of Alloy 709 fabricated using commercial practice exhibit tensile properties that exceed the minimum values specified in the ASME Code Case for commercial heat of NF709. These plates will be used to support base metal testing for the 650°C, 100,000-h Alloy 709 Code Case development, for fabrication of weldments, and for the NEUP projects.« less
Analyses of Nb-1Zr/C-103, vapor anode, multi-tube AMTEC cells
NASA Astrophysics Data System (ADS)
King, Jeffrey C.; El-Genk, Mohamed S.
2000-01-01
A high performance, Nb-1Zr/C-103, vapor anode, multi-tube AMTEC cell design is presented. The cell measures 41.27 mm in diameter, is 125.3 mm high, and has eight BASE tubes connected electrically in series. The hot structure of the cell (hot plate, BASE tubes support plate, hot plenum wall, evaporator standoff, evaporator wick, and side wall facing the BASE tubes) is made of Nb-1Zr. The cold structure of the cell (condenser, interior cylindrical thermal radiation shield, the casing and the wick of the liquid sodium return artery, and side wall above the BASE tubes) is made of the stronger, lower thermal conductivity niobium alloy C-103. This cell, which weighs 163.4 g, could deliver 7.0 We at 17% efficiency and load voltage of 3.3 V, when using TiN BASE electrodes characterized by B=75 A.K1/2/m2.Pa and G=50 and assuming BASE/electrode contact resistance of 0.06 Ω-cm2 and leakage resistance of the BASE braze structure of 3 Ω. For these performance parameters and when the interior cylindrical C-103 thermal radiation shield is covered with low emissivity rhodium, the projected specific mass of the cell is 23.4 g/We. The BASE brazes and the evaporator temperatures were below the recommended limits of 1123 K and 1023 K, respectively. In addition, the temperature margin in the cell was at least + 20 K. When electrodes characterized by B=120 A.K1/2/m2.Pa and G=10 were used, the cell power increased to 8.38 We at 3.5 V and efficiency of 18.8%, for a cell specific mass of 19.7 g/We. Issues related to structure strength of the cell and the performance degradation of the BASE and electrodes are not addressed in this paper. .
Ridge-crossing mantle plumes and gaps in tracks
NASA Astrophysics Data System (ADS)
Sleep, Norman H.
2002-12-01
Hot spot tracks approach, cross, and leave ridge axes. The complications of this process make it difficult to determine the track followed by a plume and the evolution of its vigor. When a plume is sufficiently near the ridge axis, buoyant plume material flows along the base of the lithosphere toward the axis, forming an on-axis hot spot. The track of the on-axis hot spot is a symmetric V on both plates and an unreliable indication of the path followed by the plume. Aseismic ridges form more or less along flowlines from a plume to a ridge axis when channels form at the base of the lithosphere. A dynamic effect is that off-axis hot spots appear to shut off at the time that an on-axis hot spot becomes active along an axis-approaching track. This produces a gap in the obvious track and a jump of the hot spot to the ridge axis. The gap results from the effects of ponded plume material on intraplate (membrane) stress. Membrane tension lets dikes ascend efficiently to produce obvious tracks of edifices. An off-axis hot spot shuts down when the plume is sufficiently near the ridge axis that plume material flows there, putting the nearby lithosphere above the plume into compression, preventing dikes. In addition, the off-axis thickness of plume material, which produces membrane tension, decreases as the slope of the base of the lithosphere increases beneath young lithosphere. Slow spreading rates favor gaps produced in this way. Gaps are observed near both fast and slow ridges.
Four-point Bend Testing of Irradiated Monolithic U-10Mo Fuel
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rabin, B. H.; Lloyd, W. R.; Schulthess, J. L.
2015-03-01
This paper presents results of recently completed studies aimed at characterizing the mechanical properties of irradiated U-10Mo fuel in support of monolithic base fuel qualification. Mechanical properties were evaluated in four-point bending. Specimens were taken from fuel plates irradiated in the RERTR-12 and AFIP-6 Mk. II irradiation campaigns, and tests were conducted in the Hot Fuel Examination Facility (HFEF) at Idaho National Laboratory (INL). The monolithic fuel plates consist of a U-10Mo fuel meat covered with a Zr diffusion barrier layer fabricated by co-rolling, clad in 6061 Al using a hot isostatic press (HIP) bonding process. Specimens exhibited nominal (fresh)more » fuel meat thickness ranging from 0.25 mm to 0.64 mm, and fuel plate average burnup ranged from approximately 0.4 x 1021 fissions/cm 3 to 6.0 x 1021 fissions/cm 3. After sectioning the fuel plates, the 6061 Al cladding was removed by dissolution in concentrated NaOH. Pre- and post-dissolution dimensional inspections were conducted on test specimens to facilitate accurate analysis of bend test results. Four-point bend testing was conducted on the HFEF Remote Load Frame at a crosshead speed of 0.1 mm/min using custom-designed test fixtures and calibrated load cells. All specimens exhibited substantially linear elastic behavior and failed in a brittle manner. The influence of burnup on the observed slope of the stress-strain curve and the calculated fracture strength is discussed.« less
Solar hot water system installed at Day's Lodge, Atlanta, Georgia
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
1980-09-01
The solar energy hot water system installed in the Days Inns of America, Inc., Day's Lodge I-85 and Shallowford Road, NE Atlanta, Georgia is described. This system is one of eleven systems planned under this grant and was designed to provide for 81% of the total hot water demand. There are two separate systems, each serving one building of the lodge (total of 65 suites). The entire system contains only potable city water. The 1024 square feet of Grumman Sunstream Model 332 liquid flat plate collectors and the outside piping drains whenever the collector plates approach freezing or when powermore » is interrupted. Solar heated water from the two above ground cement lined steel tanks (1000 gallon tank) is drawn into the electric domestic hot water (DHW) tanks as hot water is drawn. Electric resistance units in the DHW tanks top off the solar heated water, if needed, to reach thermostat setting. Operation of this system was begun in August, 1979. The solar components were partly funded ($18,042 of $36,084 cost) by the Department of Energy.« less
Casarrubea, Maurizio; Faulisi, Fabiana; Magnusson, Magnus S; Crescimanno, Giuseppe
2016-08-01
The largest amount of researches on the hot-plate test was carried out using quantitative assessments. However, the evaluation of the relationships among the different elements that compose the behavioral response to pain requires different approaches. Although previous studies have provided clear information on the behavioral structure of the response, no data are available on its temporal structure. The objective of this study was to investigate the temporal structure of the behavioral response to pain in Wistar rat tested in hot-plate and how this structure was influenced by morphine-induced analgesia. The behavior of four groups of subjects tested in hot-plate, one administered saline and three with different doses (3, 6, 12 mg/kg) of morphine IP, was analyzed by means of quantitative and t-pattern analyses. The latter is a multivariate technique able to detect the existence of statistically significant temporal relationships among the behavioral events in time. A clear-cut influence of morphine on quantitative parameters of the response to the noxious stimulation was observed. T-pattern analysis evidenced profound structural changes of behavior. Twenty-four different t-patterns were identified following saline, whereas a dose-dependent reduction was observed following morphine. Such a reduction was accompanied by a decrease of the total amount of t-patterns detected. Morphine, by reducing the effects of the noxious stimulation, orients animal behavior prevalently toward exploratory t-patterns. In addition, it is suggested that the temporal structure of the response is very quickly organized and adapted to environmental noxious cues.
Probing the Hawaiian Hot Spot With New Broadband Ocean Bottom Instruments
NASA Astrophysics Data System (ADS)
Laske, Gabi; Collins, John A.; Wolfe, Cecily J.; Solomon, Sean C.; Detrick, Robert S.; Orcutt, John A.; Bercovici, David; Hauri, Erik H.
2009-10-01
The Hawaiian hot spot is regarded as the textbook example of the product of a deep-rooted mantle plume [Wilson, 1963; Morgan, 1971]. Its isolated location, far from any plate boundary, should provide an opportunity to test most basic hypotheses on the nature of plume-plate interaction and related magmatism [e.g., Ribe and Christensen, 1999]. Yet the lack of crucial geophysical data has sustained a debate about whether Hawaii's volcanism is plume-related or is instead the consequence of more shallow processes, such as the progressive fracturing of the plate in response to extensional stresses [Turcotte and Oxburgh, 1973]. In the plume model for Hawaii's volcanism, hot material is expected to ascend near vertically within the more viscous surrounding mantle before ponding and spreading laterally beneath the rigid lithosphere. Mantle convection in general, and the fast moving Pacific plate in particular, shear and tilt the rising plume. The plume top is dragged downstream by the plate, and this dragged material may give rise to an elongated bathymetric swell [Davies, 1988; Olson, 1990; Sleep, 1990; Phipps Morgan et al., 1995]. However, identifying the dominant cause of the swell remains elusive, and proposed mechanisms include thermal rejuvenation, dynamic support, compositional buoyancy, and mechanical erosion (see Li et al. [2004] for a summary). There is also considerable debate about the continuity of the plume within the mantle, how discrete islands are formed, and how a deep-rooted plume interacts with the mantle transition zone [e.g., van Keken and Gable, 1995].
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aydogan, E.; Pal, S.; Anderoglu, O.
In this paper, texture and microstructure of tubes and plates fabricated from a nanostructured ferritic alloy (14YWT), produced either by spray forming followed by hydrostatic extrusion (Process I) or hot extrusion and cross-rolling a plate followed by hydrostatic tube extrusion (Process II) have been characterized in terms of their effects on texture and grain boundary character. Hydrostatic extrusion results in a combination of plane strain and shear deformations which generate low intensity α- and γ-fiber components of {001}<110> and {111}<110> together with a weak ζ-fiber component of {011}<211> and {011}<011>. In contrast, multi-step plane strain deformation by hot extrusion andmore » cross-rolling of the plate leads to a strong texture component of {001}<110> together with a weaker {111}<112> component. Although the total strains are similar, shear dominated deformation leads to much lower texture indexes compared to plane strain deformations. Further, the texture intensity decreases after hydrostatic extrusion of the alloy plate formed by plane strain deformation, due to a lower number of activated slip systems during shear dominated deformation. Finally and notably, hot extruded and cross-rolled plate subjected to plane strain deformation to ~50% engineering strain creates only a modest population of low angle grain boundaries, compared to the much larger population observed following the combination of plane strain and shear deformation of ~44% engineering strain resulting from subsequent hydrostatic extrusion.« less
Aydogan, E.; Pal, S.; Anderoglu, O.; ...
2016-03-08
In this paper, texture and microstructure of tubes and plates fabricated from a nanostructured ferritic alloy (14YWT), produced either by spray forming followed by hydrostatic extrusion (Process I) or hot extrusion and cross-rolling a plate followed by hydrostatic tube extrusion (Process II) have been characterized in terms of their effects on texture and grain boundary character. Hydrostatic extrusion results in a combination of plane strain and shear deformations which generate low intensity α- and γ-fiber components of {001}<110> and {111}<110> together with a weak ζ-fiber component of {011}<211> and {011}<011>. In contrast, multi-step plane strain deformation by hot extrusion andmore » cross-rolling of the plate leads to a strong texture component of {001}<110> together with a weaker {111}<112> component. Although the total strains are similar, shear dominated deformation leads to much lower texture indexes compared to plane strain deformations. Further, the texture intensity decreases after hydrostatic extrusion of the alloy plate formed by plane strain deformation, due to a lower number of activated slip systems during shear dominated deformation. Finally and notably, hot extruded and cross-rolled plate subjected to plane strain deformation to ~50% engineering strain creates only a modest population of low angle grain boundaries, compared to the much larger population observed following the combination of plane strain and shear deformation of ~44% engineering strain resulting from subsequent hydrostatic extrusion.« less
Installation Assessment of Frankford Arsenal.
1977-10-01
sulfate , sulfuric acid , ac ’solution 40 Hot water bath 41 Nickel plate Nickel sulfate and chloride sulfuric acid , acid ...solution 42 Chromium Copper plate Copper sulfate and sulfuric acid , acid solution 11-14 TABLE 11-2 (continued) Tank No. Plating Process Use Contents...46 Water rinse Water 47 Water rinse Water 48 Water rinse Water 49 Acid Chromic acid , acetic acid , nickel sulfate and sulfuric
NASA Astrophysics Data System (ADS)
Koppers, Anthony A. P.; Gowen, Molly D.; Colwell, Lauren E.; Gee, Jeffrey S.; Lonsdale, Peter F.; Mahoney, John J.; Duncan, Robert A.
2011-12-01
In this study we present 42 new 40Ar/39Ar incremental heating age determinations that contribute to an updated age progression for the Louisville seamount trail. Louisville is the South Pacific counterpart to the Hawaiian-Emperor seamount trail, both trails representing intraplate volcanism over the same time interval (˜80 Ma to present) and being examples of primary hot spot lineaments. Our data provide evidence for an age-progressive trend from 71 to 21 Ma. Assuming fixed hot spots, this makes possible a direct comparison to the Hawaiian-Emperor age progression and the most recent absolute plate motion (APM) model (WK08G) of Wessel and Kroenke (2008). We observe that for the Louisville seamount trail the measured ages are systematically older relative to both the WK08G model predictions and Hawaiian seamount ages, with offsets ranging up to 6 Myr. Taking into account the uncertainty about the duration of eruption and magmatic succession at individual Louisville volcanoes, these age offsets should be considered minimum estimates, as our sampling probably tended to recover the youngest lava flows. These large deviations point to either a contribution of inter-hot spot motion between the Louisville and Hawaiian hot spots or to a more easterly location of the Louisville hot spot than the one inferred in the WK08G model. Both scenarios are investigated in this paper, whereby the more eastern hot spot location (52.0°S, 134.5°W versus 52.4°S, 137.2°W) reduces the average age offset, but still results in a relatively large maximum offset of 3.7 Myr. When comparing the new ages to the APM models (S04P, S04G) by Steinberger et al. (2004) that attempt to compensate for the motion of hot spots in the Pacific (Hawaii) or globally (Hawaii, Louisville, Reunion and Walvis), the measured and predicted ages are more in agreement, showing only a maximum offset of 2.3 Myr with respect to the S04G model. At face value these more advanced APM models, which consider both plate and hot spot motions, therefore provide a better fit to the new Louisville age data. The fit is particularly good for seamounts younger than 50 Ma, a period for which there is little predicted motion for the Louisville hot spot and little inter-hot spot motion with Hawaii. However, discrepancies in the Louisville age-distance record prior to 50 Ma indicate there is an extra source of inter-hot spot motion between Louisville and the other Pacific hot spots that was not corrected for in the global S04G model. Finally, based on six new 40Ar/39Ar age dates, the 169°W bend in the Louisville seamount trail seems to have formed at least 3 Myr before the formation of the Hawaiian-Emperor bend. The timing of the most acute parts of both bends thus appears to be asynchronous, which would require other processes (e.g., plume motions) than a global plate motion change between 50 and 47 Ma to explain these two observations.
NASA Astrophysics Data System (ADS)
Koppers, Anthony A. P.; Staudigel, Hubert; Pringle, Malcolm S.; Wijbrans, Jan R.
2003-10-01
South Pacific intraplate volcanoes have been active since the Early Cretaceous. Their HIMU-EMI-EMII mantle sources can be traced back into the West Pacific Seamount Province (WPSP) using plate tectonic reconstructions, implying that these distinctive components are enduring features within the Earth's mantle for, at least, the last 120 Myr. These correlations are eminent on the scale of the WPSP and the South Pacific Thermal and Isotopic Anomaly (SOPITA), but the evolution of single hot spots emerges notably more complicated. Hot spots in the WPSP and SOPITA mantle regions typically display intermittent volcanic activity, longevities shorter than 40 Myr, superposition of hot spot volcanism, and motion relative to other hot spots. In this review, we use 40Ar/39Ar seamount ages and Sr-Nd-Pb isotopic signatures to map out Cretaceous volcanism in the WPSP and to characterize its evolution with respect to the currently active hot spots in the SOPITA region. Our plate tectonic reconstructions indicate cessation of volcanism during the Cretaceous for the Typhoon and Japanese hot spots; whereas the currently active Samoan, Society, Pitcairn and Marquesas hot spots lack long-lived counterparts in the WPSP. These hot spots may have become active during the last 20 Myr only. The other WPSP seamount trails can be only "indirectly" reconciled with hot spots in the SOPITA region. Complex age distributions in the Magellan, Anewetak, Ralik and Ratak seamount trails would necessitate the superposition of multiple volcanic trails generated by the Macdonald, Rurutu and Rarotonga hot spots during the Cretaceous; whereas HIMU-type seamounts in the Southern Wake seamount trail would require 350-500 km of hot spot motion over the last 100 Myr following its origination along the Mangaia-Rurutu "hotline" in the Cook-Austral Islands. These observations, however, violate all assumptions of the classical Wilson-Morgan hot spot hypothesis, indicating that long-lived, deep and fixed mantle plumes cannot explain the intraplate volcanism of the South Pacific region. We argue that the observed short-lived and discontinuous intraplate volcanism has been produced by another type of hot spot-related volcanism, as opposed to the strong and continuous Hawaiian-type hot spots. Our results also indicate that other geological processes (plate tension, hotlines, faulting, wetspots, self-propagating volcanoes) may act in conjunction with hot spot volcanism in the South Pacific. In all these scenarios, intraplate volcanism has to be controlled by "broad-scale" events giving rise to multiple closely-spaced mantle plumelets, each with a distinct isotopic signature, but only briefly active and stable over geological time. It seems most likely that these plumelets originate and dissipate at very shallow mantle depths, where they may shoot off as thin plumes from the top of a "superplume" that is present in the South Pacific mantle. The absence of clear age progressions in most seamount trails and periodic flare-ups of massive intraplate volcanism in the South Pacific (such as the one in the Cretaceous and one starting 30 Myr ago) show that regional extension (caused by changes in the global plate circuit and/or the rise-and-fall of an oscillating superplume) may be driving the waxing and waning of intraplate volcanism in the South Pacific.
Wheelspace windage cover plate for turbine
Lathrop, Norman Douglas
2002-01-01
Windage cover plates are secured between the wheels and spacer of a turbine rotor to prevent hot flow path gas ingestion into the wheelspace cavities. Each cover plate includes a linear, axially extending body curved circumferentially with a radially outwardly directed wall at one axial end. The wall defines a axially opening recess for receiving a dovetail lug. The cover plate includes an axially extending tongue received in a circumferential groove of the spacer. The cover plate is secured with the tongue in the groove and dovetail lug in the recess. Lap joints between circumferentially adjacent cover plates are provided.
Shock initiation of explosives: High temperature hot spots explained
NASA Astrophysics Data System (ADS)
Bassett, Will P.; Johnson, Belinda P.; Neelakantan, Nitin K.; Suslick, Kenneth S.; Dlott, Dana D.
2017-08-01
We investigated the shock initiation of energetic materials with a tabletop apparatus that uses km s-1 laser-driven flyer plates to initiate tiny explosive charges and obtains complete temperature histories with a high dynamic range. By comparing various microstructured formulations, including a pentaerythritol tetranitrate (PETN) based plastic explosive (PBX) denoted XTX-8003, we determined that micron-scale pores were needed to create high hot spot temperatures. In charges where micropores (i.e., micron-sized pores) were present, a hot spot temperature of 6000 K was observed; when the micropores were pre-compressed to nm scale, however, the hot spot temperature dropped to ˜4000 K. By comparing XTX-8003 with an analog that replaced PETN by nonvolatile silica, we showed that the high temperatures require gas in the pores, that the high temperatures were created by adiabatic gas compression, and that the temperatures observed can be controlled by the choice of ambient gases. The hot spots persist in shock-compressed PBXs even in vacuum because the initially empty pores became filled with gas created in-situ by shock-induced chemical decomposition.
On the propagation mechanism of a detonation wave in a round tube with orifice plates
NASA Astrophysics Data System (ADS)
Ciccarelli, G.; Cross, M.
2016-09-01
This study deals with the investigation of the detonation propagation mechanism in a circular tube with orifice plates. Experiments were performed with hydrogen air in a 10-cm-inner-diameter tube with the second half of the tube filled with equally spaced orifice plates. A self-sustained Chapman-Jouguet (CJ) detonation wave was initiated in the smooth first half of the tube and transmitted into the orifice-plate-laden second half of the tube. The details of the propagation were obtained using the soot-foil technique. Two types of foils were used between obstacles, a wall-foil placed on the tube wall, and a flat-foil (sooted on both sides) placed horizontally across the diameter of the tube. When placed after the first orifice plate, the flat foil shows symmetric detonation wave diffraction and failure, while the wall foil shows re-initiation via multiple local hot spots created when the decoupled shock wave interacts with the tube wall. At the end of the tube, where the detonation propagated at an average velocity much lower than the theoretical CJ value, the detonation propagation is much more asymmetric with only a few hot spots on the tube wall leading to local detonation initiation. Consecutive foils also show that the detonation structure changes after each obstacle interaction. For a mixture near the detonation propagation limit, detonation re-initiation occurs at a single wall hot spot producing a patch of small detonation cells. The local overdriven detonation wave is short lived, but is sufficient to keep the global explosion front propagating. Results associated with the effect of orifice plate blockage and spacing on the detonation propagation mechanism are also presented.
21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.
Code of Federal Regulations, 2012 CFR
2012-04-01
... filter paper with the aid of suction. Transfer the filtrate to flat glass dishes that are warmed on a hot.... Maintain the temperature of the contents of the flask at 150 °F for 2 hours using a hot plate while also...
21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.
Code of Federal Regulations, 2011 CFR
2011-04-01
... filter paper with the aid of suction. Transfer the filtrate to flat glass dishes that are warmed on a hot.... Maintain the temperature of the contents of the flask at 150 °F for 2 hours using a hot plate while also...
21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.
Code of Federal Regulations, 2013 CFR
2013-04-01
... filter paper with the aid of suction. Transfer the filtrate to flat glass dishes that are warmed on a hot.... Maintain the temperature of the contents of the flask at 150 °F for 2 hours using a hot plate while also...
21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.
Code of Federal Regulations, 2010 CFR
2010-04-01
... filter paper with the aid of suction. Transfer the filtrate to flat glass dishes that are warmed on a hot.... Maintain the temperature of the contents of the flask at 150 °F for 2 hours using a hot plate while also...
Development of an economic solar heating system with cost efficient flat plate collectors
NASA Astrophysics Data System (ADS)
Eder-Milchgeisser, W.; Burkart, R.
1980-10-01
Mass produced flat plate solar collectors were worked into the design of a system for heating a swimming pool and/or providing domestic hot water. The collector characteristics, including physical and mechanical data as well as theoretical energy conversion efficiency, are presented. The collector was tested and service life efficiency was determined. The mounting of the collector, depending on roof type, is explained. Both in service and laboratory test results demonstrate the cost effectiveness of the system. Further improvement of efficiency is envisaged with automatic flow control in the solar collector and hot water circuits.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Khan, S. F.; Izumi, N.; Glenn, S.
At the National Ignition Facility, the symmetry of the hot spot of imploding capsules is diagnosed by imaging the emitted x-rays using gated cameras and image plates. The symmetry of an implosion is an important factor in the yield generated from the resulting fusion process. The x-ray images are analyzed by decomposing the image intensity contours into Fourier and Legendre modes. This paper focuses on the additional protocols for the time-integrated shape analysis from image plates. Here, for implosions with temperatures above ~4keV, the hard x-ray background can be utilized to infer the temperature of the hot spot.
NASA Astrophysics Data System (ADS)
Miranda, G.; Ferreira, P.; Buciumeanu, M.; Cabral, A.; Fredel, M.; Silva, F. S.; Henriques, B.
2017-08-01
The current trend to replace cobalt in diamond cutting tools (DCT) for stone cutting has motivated the study of alternative materials for this end. The present study characterizes several copper-nickel-based materials (Cu-Ni; Cu-Ni-10Sn, Cu-Ni-15Sn, Cu-Ni-Sn-2WC and Cu-Ni-Sn-10WC) for using as matrix material for diamond cutting tools for stone. Copper-nickel-based materials were produced by hot pressing, at a temperature of 850 °C during 15 min and under an applied pressure of 50 MPa. The mechanical properties were evaluated though the shear strength and hardness values. The microstructures and fracture surfaces were analyzed by SEM. The wear behavior of all specimens was assessed using a reciprocating ball-on-plate tribometer. The hot pressing produced compacts with good densification. Sn and WC promoted enhanced mechanical properties and wear performance to Cu-Ni alloys. Cu-Ni-10Sn and Cu-Ni-10Sn-2WC displayed the best compromise between mechanical and wear performance.
Fabrication and Testing of a Tubular Thermoelectric Module Based on Oxide Elements
NASA Astrophysics Data System (ADS)
Merkulov, O. V.; Politov, B. V.; Chesnokov, K. Yu.; Markov, A. A.; Leonidov, I. A.; Patrakeev, M. V.
2018-02-01
A thermoelectric module with a tubular design, considered as particularly promising for energy recovery from hot exhaust gases of vehicles was fabricated and successfully tested under laboratory condition. The module included 24 functional oxide elements synthesized by conventional methods. Elements of p-type were made of cobalt-based oxide Ca2.7Bi0.3Co4O9, while n-type elements were produced from manganese-based oxide CaMn0.95Ta0.05O3. The module was assembled using silver paste and clamping mechanisms, with the thermoelectric elements electrically connected in series by metal plates (copper, silver) and placed around the hot tube. The output power of 138 mW was achieved under a temperature gradient of 430°C with a hot side temperature of 514°C. The tested module is characterized by an advantageous manufacturing factor of 0.87 at the contact resistance of 0.44 Ω, but a relatively low output power density per volume and per mass. Possible means by which the module's operational characteristics could be improved are considered.
NASA Astrophysics Data System (ADS)
Aldrich, M. J.; Adams, Andrew I.; Escobar, Carlos
1991-03-01
The structural geology of the Platanares geothermal site in western Honduras, located about 25 km south of the northern boundary of the Caribbean plate, is the result of post Early Miocene extensional deformation. Normal faults, many with listric geometries, are numerous throughout the area. Strike-slip faulting has mostly occurred on reactived normal faults. Analysis of the fault slip data shows an older minimum principal stress, σ 3, oriented approximately N-S and a contemporary σ 3 tensional and oriented ENE-WSW. The analysis suggests that σ 3 has rotated clockwise since the Early Miocene although some of the change in orientation of σ 3 might reflect counterclockwise rotation of the crust about a vertical axis. The σ 1 and σ 2 stress axes apparently switched recently, with the σ 3 axis remaining unchanged. These results are consistent with a tectonic model in which the east-drifting Caribbean plate is pinned against North America by the subducting Cocos plate (Malfait and Dinkleman, 1972) and the northern and southern margins of the Caribbean plate are broad, mobile zones that are undergoing counterclockwise and clockwise rotations respectively (Gose, 1985). The majority of the hot springs at Platanares lie along Quebrada del Agua Caliente. Fractures control the movement of the geothermal waters. Hot springs occur along joints and faults and, in places, hot water flows laterally along bedding planes. If the fractures also control the movement of water at depth then the source reservoir of the geothermal waters may be located northeast of the principal hot spring areas along the quebrada since the majority of the faults dip in that direction. However, if the fault that seems to have controlled the development of Quebrada del Agua Caliente is vertical as inferred then the main reservoir may lie directly beneath this drainage.
Fooladi, J; Sajjadian, A
2010-01-01
Background Screening is a routine procedure for isolation of microorganisms which are able to produce special metabolites. Purified thermostable α-amylase from bacterial sources is widely used in different industries. In this study we analyzed samples collected from three different hot springs in Iran to detect any strains capable of producing thermostable α-amylase. Materials and Methods Hot water samples from Larijan (67°C, pH 6.5), Mahallat (46°C, pH 7), and Meshkinshahr (82°C, pH 6), were cultivated in screening starch agar plates and incubated at 65°C for 24 hours. Thereafter, the plates were stained with Gram's iodine solution. Results and Discussion The bacterial colonies from the Meshkinshahr hot-spring produced the largest haloforming zone. Based on the phenotypic tests, the strain was identified as Bacillus sp. The culture condition was optimized for biosynthesis of α-amylase. The enzyme was produced at maximum level when it was incubated at 70°C in the presence of soluble starch (1%) at pH 6. The addition of calcium (10 mM) and peptone (1%) to the mineral medium, shortened the lag period and improved the growth and α-amylase synthesis. The addition of glucose (1%) to the culture greatly diminished the syntheses of α -amylase. Importantly, the enzyme extract retained 100% activity when incubated for 45 minutes at 100°C. Conclusion The Meshkinshahr hot-spring is rich in the Bacillus spp thermostable α-amylase producing strain of the thermophilic bacterial population. Iranian hot-springs like Meshkinshahr, have large microbial storages and can be used as sources of different biological products like enzymes. The enzyme which was produced with Bacillus sp. could hydrolyse polymers like starch and was used at laboratory scale successfully. PMID:22347550
Segerström, Susanna; Ruyter, I Eystein
2009-09-01
For long-term stability the adhering interfaces of an implant-retained supraconstruction of titanium/carbon-graphite fiber-reinforced (CGFR) polymer/opaquer layer/denture base polymer/denture teeth must function as a unity. The aim was to evaluate adhesion of CGFR polymer to a titanium surface or CGFR polymer to two different opaquer layers/with two denture base polymers. Titanium plates were surface-treated and silanized and combined with a bolt of CGFR polymer or denture base polymer (Probase Hot). Heat-polymerized plates of CGFR polymer (47 wt% fiber) based on poly(methyl methacrylate) and a copolymer matrix were treated with an opaquer (Sinfony or Ropak) before a denture base polymer bolt was attached (Probase Hot or Lucitone 199). All specimens were heat-polymerized, water saturated (200 days) and thermally cycled (5000 cycles, 5/55 degrees C) before shear bond testing. Silicatized titanium surfaces gave higher bond strength to CGFR polymer (16.2+/-2.34 and 18.6+/-1.32) MPa and cohesive fracture than a sandblasted surface (5.9+/-2.11) MPa where the fracture was adhesive. The opaquer Sinfony gave higher adhesion values and mainly cohesive fractures than the opaquer Ropak. Different surface treatments (roughened or polished) of the CGFR polymer had no effect on bond strength. The fracture surfaces of silicatized titanium/CGFR polymer/opaquer layer (Sinfony)/denture base polymers were mainly cohesive. A combination of these materials in an implant-retained supraconstruction is promising for in vivo evaluation.
NASA Astrophysics Data System (ADS)
Hasan, Mohammad Nasim; Rabbi, Kazi Fazle; Sabah, Arefiny; Ahmed, Jannat; Kuri, Subrata Kumar; Rakibuzzaman, S. M.
2017-06-01
Investigation of Molecular level phase change phenomena are becoming important in heat and mass transfer research at a very high rate, driven both by the need to understand certain fundamental phenomena as well as by a plethora of new and forthcoming applications in the areas of micro- and nanotechnologies. Molecular dynamics simulation has been carried out to go through the evaporation and condensation characteristics of thin liquid argon film in Nano-scale confinement. In the present study, a cuboid system is modeled for understanding the Nano-scale physics of simultaneous evaporation and condensation. The cuboid system consists of hot and cold parallel platinum plates at the bottom and top ends. The fluid comprised of liquid argon film at the bottom plate and vapor argon in between liquid argon and upper plate of the domain. Three different simulation domains have been created here: (i) Both platinum plates are considered flat, (ii) Upper plate consisting of transverse slots of low height and (iii) Upper plate consisting of transverse slots of bigger height. Considering hydrophilic nature of top and bottom plates, two different high temperatures of the hot wall was set and an observation was made on normal and explosive vaporizations and their impacts on thermal transport. For all the structures, equilibrium molecular dynamics (EMD) was performed to reach equilibrium state at 90 K. Then the lower wall is set to two different temperatures like 110 K and 250 K for all three models to perform non-equilibrium molecular dynamics (NEMD). For vaporization, higher temperature of the hot wall led to faster transport of the liquid argon as a cluster moving from hot wall to cold wall. But excessive temperature causes explosive boiling which seems not good for heat transportation because of less phase change. In case of condensation, an observation was made which indicates that the nanostructured transverse slots facilitate condensation. Two factors affect the rate of condensation when nanostructures are there: (i) increased surface area and (ii) the nanostructure height. The variation of temperature and evaporation number with respect to time was monitored for all cases. An estimation of heat fluxes normal to top and bottom walls also was made to focus the effectiveness of heat transfer in hydrophilic confinement.
Llinas’ Phase Reset Mechanism Delays the Onset of Chaos in Shark and Dolphin Wall Turbulence
2014-02-10
eruption due to plate tectonics . (The plate becomes locally thin and is unable to prevent the high-pressure hot magma from erupting.) The vorticity...flat plate value. The spacing between riblet peaks s+= 10 is used unless noted. KM gives the "strength" of the riblets, where the terms "weak" and...exhibit spanwise variations in skin friction coefficients and integral boundary layer properties, even in flat plate experiments where great care has
Photovoltaic module hot spot durability design and test methods
NASA Technical Reports Server (NTRS)
Arnett, J. C.; Gonzalez, C. C.
1981-01-01
As part of the Jet Propulsion Laboratory's Low-Cost Solar Array Project, the susceptibility of fat-plate modules to hot-spot problems is investigated. Hot-spot problems arise in modules when the cells become back-biased and operate in the negative-voltage quadrant, as a result of short-circuit current mismatch, cell cracking or shadowing. The details of a qualification test for determining the capability of modules of surviving field hot-spot problems and typical results of this test are presented. In addition, recommended circuit-design techniques for improving the module and array reliability with respect to hot-spot problems are presented.
Comparative effects of Rauwolfia vomitoria and chlorpromazine on social behaviour and pain
Bisong, Sunday; Brown, Richard; Osim, Eme
2011-01-01
Background: Rauwolfia vomitoria has been used in Nigeria to manage psychiatric disorders despite orthodox medicine. Aims: This research was therefore aimed at comparing the effects of R. vomitoria, chlorpromazine and reserpine on social behaviour and pain in mice. Materials and Methods: Ninety male CD-1 mice (32 – 38g body weight) were grouped into 3 with 5 subgroups (n=6) each. Mice were given chlorpromazine (0.0, 0.25, 1.0, 2.0, 4.0 mg/kg i.p.), 30 minutes before testing and R. vomitoria (0.0, 0.25, 1.0, 2.0, 4.0 mg/kg, i.p.) and reserpine (0.0, 0.1, 0.4, 0.8, 1.6 mg/kg, i.p) 24 hours before testing. Nesting score assessed social behaviour while the tail flick and hot plate analgesiometers assessed pain. Results: Chlorpromazine dose-dependently decreased nesting score (F4,25 = 5.5660; p< 0.01), indicating decreased social behaviour (social loss) in the mice. Although R. vomitoria did not affect nesting score, reserpine decreased the nesting score (social loss). In the pain test, chlorpromazine did not alter tail flick latency but decreased hind paw lick latency in the hot plate at 2.0 and 4.0 mg/kg (p< 0.01), indicating increased pain sensitivity at these doses which may indirectly increase social withdrawal and thus aggravating depression. R. vomitoria however, increased tail flick and hind paw lick latencies in the hot plate test (p< 0.05) indicating decreased pain sensitivity. Reserpine, like R. vomitoria, increased latency of hind paw lick in the hot plate. Conclusion: R. vomitoria has a high potential as an antipsychotic and may have advantage over chlorpromazine; it is not necessary to isolate active components from this herb. PMID:22540065
Gholami, Morteza; Saboory, Ehsan; Mehraban, Sogol; Niakani, Afsaneh; Banihabib, Nafiseh; Azad, Mohamad-Reza; Fereidoni, Javid
2015-01-01
Morphine and tramadol which have analgesic effects can be administered acutely or chronically. This study tried to investigate the effect of these drugs at various times by using different methods of administration (intraperitoneal, oral, acute and chronic). Sixty adult female rats were divided into six groups. They received saline, morphine or tramadol (20 to 125 mg/Kg) daily for 15 days. A hot plate test was performed for the rats at the 1st, 8th and 15th days. After drug withdrawal, the hot plate test was repeated at the 17th, 19th, and 22nd days. There was a significant correlation between the day, drug, group, and their interaction (P<0.001). At 1st day (d1), both morphine, and tramadol caused an increase in the hot plate time comparing to the saline groups (P<0.001), while there was no correlation between drug administration methods of morphine and/or tramadol. At the 8th day (d8), morphine and tramadol led to the most powerful analgesic effect comparing to the other experimental days (P<0.001). At the 15th day (d15), their effects diminished comparing to the d8. After drug withdrawal, analgesic effect of morphine, and tramadol disappeared. It can be concluded that the analgesic effect of morphine and tramadol increases with the repeated use of them. Thereafter, it may gradually decrease and reach to a level compatible to d1. The present data also indicated that although the analgesic effect of morphine and tramadol is dose-and-time dependent, but chronic exposure to them may not lead to altered nociceptive responses later in life. PMID:25561936
Farallon slab detachment and deformation of the Magdalena Shelf, southern Baja California
Brothers, Daniel S.; Harding, Alistair J.; Gonzalez-Fernandez, Antonio; Holbrook, W.S. Steven; Kent, Graham M.; Driscoll, Neal W.; Fletcher, John M.; Lizarralde, Daniel; Umhoefer, Paul J.; Axen, Gary
2012-01-01
Subduction of the Farallon plate beneath northwestern Mexico stalled by ~12 Ma when the Pacific-Farallon spreading-ridge approached the subduction zone. Coupling between remnant slab and the overriding North American plate played an important role in the capture of the Baja California (BC) microplate by the Pacific Plate. Active-source seismic reflection and wide-angle seismic refraction profiles across southwestern BC (~24.5°N) are used to image the extent of remnant slab and study its impact on the overriding plate. We infer that the hot, buoyant slab detached ~40 km landward of the fossil trench. Isostatic rebound following slab detachment uplifted the margin and exposed the Magdalena Shelf to wave-base erosion. Subsequent cooling, subsidence and transtensional opening along the shelf (starting ~8 Ma) starved the fossil trench of terrigenous sediment input. Slab detachment and the resultant rebound of the margin provide a mechanism for rapid uplift and exhumation of forearc subduction complexes.
Measurements of hot-electron temperature in laser-irradiated plasmas
Solodov, A. A.; Yaakobi, B.; Edgell, D. H.; ...
2016-10-26
In a recently published work 1–3 we reported on measuring the total energy of hot electrons produced by the interaction of a nanosecond laser with planar CH-coated molybdenum targets, using the Mo K α emission. The temperature of the hot electrons in that work was determined by the high-energy bremsstrahlung [hard x-ray (HXR)] spectrum measured by a three-channel fluorescence-photomultiplier detector (HXRD). In the present work, we replaced the HXRD with a nine-channel image-plate (IP)–based detector (HXIP). For the same conditions (irradiance of the order of 10 14 W/cm 2; 2-ns pulses) the measured temperatures are consistently lower than those measuredmore » by the HXRD (by a factor ~1.5 to 1.7). In addition, we supplemented this measurement with three experiments that measure the hot-electron temperature using K α line-intensity ratios from high-Z target layers, independent of the HXR emission. These experiments yielded temperatures that were consistent with those measured by the HXIP. We showed that the thermal x-ray radiation must be included in the derivation of total energy in hot electrons (E hot), and that this makes E hot only weakly dependent on hot-electron temperature. For a given x-ray emission in inertial confinement fusion compression experiments, this result would lead to a higher total energy in hot electrons, but the preheat of the compressed fuel may be lower because of the reduced hot-electron range.« less
Measurements of hot-electron temperature in laser-irradiated plasmas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Solodov, A. A.; Yaakobi, B.; Edgell, D. H.
In a recently published work 1–3 we reported on measuring the total energy of hot electrons produced by the interaction of a nanosecond laser with planar CH-coated molybdenum targets, using the Mo K α emission. The temperature of the hot electrons in that work was determined by the high-energy bremsstrahlung [hard x-ray (HXR)] spectrum measured by a three-channel fluorescence-photomultiplier detector (HXRD). In the present work, we replaced the HXRD with a nine-channel image-plate (IP)–based detector (HXIP). For the same conditions (irradiance of the order of 10 14 W/cm 2; 2-ns pulses) the measured temperatures are consistently lower than those measuredmore » by the HXRD (by a factor ~1.5 to 1.7). In addition, we supplemented this measurement with three experiments that measure the hot-electron temperature using K α line-intensity ratios from high-Z target layers, independent of the HXR emission. These experiments yielded temperatures that were consistent with those measured by the HXIP. We showed that the thermal x-ray radiation must be included in the derivation of total energy in hot electrons (E hot), and that this makes E hot only weakly dependent on hot-electron temperature. For a given x-ray emission in inertial confinement fusion compression experiments, this result would lead to a higher total energy in hot electrons, but the preheat of the compressed fuel may be lower because of the reduced hot-electron range.« less
Effect of microstructure of superalloy guide plate on its surface wear resistance
NASA Astrophysics Data System (ADS)
Zhou, Jianbo; Zhang, Xizhen
2018-03-01
The microstructure had been observed for guide plate, the guide plate be made of casting for groove controlling of hot rolled seamless tube, be produced for the production of 1600 seamless steel pipe,which cause obvious surface deformation and can not be normally produced. The alloy elements in matrix and precipitate phase of the guide plate were analyzed with the help of EDS. The results show that the wear resistance of the guide plate is directly affected by the fact that the guide plate is unable to form typical carbides, it shows that the formation of typical carbide strengthening plays an important role in improving the surface wear resistance of the guide plate.
NASA Astrophysics Data System (ADS)
Kuri, Subrata Kumar; Rakibuzzaman, S. M.; Sabah, Arefiny; Ahmed, Jannat; Hasan, Mohammad Nasim
2017-12-01
Molecular dynamics simulation has been carried out to go through the evaporation and condensation characteristics of thin liquid argon film in nanoscale confinement having nanostructured boundary. Nanoscale confinement under consideration consists of hot and cold parallel platinum plates at the bottom and top end of a model cuboid inside which the fluid domain comprised of liquid argon film at the bottom plate and vapor argon in between liquid argon and upper plate of the confinement. Three different confinement configurations have been considered here: (i) Both platinum plates are flat, (ii) Upper plate consisting of transverse slots and (iii) Both plates consisting of transverse slots. The height of the slots is 1.5 nm. Considering hydrophilic nature of top and bottom plates, two different high temperatures of the hot wall was set and an observation was made. For all the structures, equilibrium molecular dynamics (EMD) was performed to reach equilibrium state at 90 K. Then the lower wall is set to two different temperatures like 110 K and 250 K for all three models to perform non-equilibrium molecular dynamics (NEMD). Various system characteristics such as atomic distribution, wall heat flux, evaporative mass flux etc. have been obtained and discussed to have a clear understanding of the effect of nanotextured surface on phase change phenomena.
NASA Astrophysics Data System (ADS)
Hammerschmidt, Ulf; Hameury, Jacques; Strnad, Radek; Turzó-Andras, Emese; Wu, Jiyu
2015-07-01
This paper presents a critical review of current industrial techniques and instruments to measure the thermal conductivity of thermal insulation materials, especially those insulations that can operate at temperatures above and up to . These materials generally are of a porous nature. The measuring instruments dealt with here are selected based on their maximum working temperature that should be higher than at least . These instruments are special types of the guarded hot-plate apparatus, the guarded heat-flow meter, the transient hot-wire and hot-plane instruments as well as the laser/xenon flash devices. All technical characteristics listed are quoted from the generally accessible information of the relevant manufacturers. The paper includes rankings of the instruments according to their standard retail price, the maximum sample size, and maximum working temperature, as well as the minimum in their measurement range.
Silver plating technique seals leaks in thin wall tubing joints
NASA Technical Reports Server (NTRS)
Blenderman, W. H.
1966-01-01
Leaks in thin wall tubing joints are sealed by cleaning and silver plating the hot gas side of the joint in the leakage area. The pressure differential across the silver during hydrostatic test and subsequent use forces the ductile silver into the leak area and seals it.
Solar heating and hot water system installed at Shoney's Restaurant, North Little Rock, Arkansas
NASA Technical Reports Server (NTRS)
1980-01-01
A solar heating system designed to supply a major portion of the space and water heating requirements for a restaurant is described. The restaurant has a floor space of approximately 4,650 square feet and requires approximate 1500 gallons of hot water daily. The solar energy system consists of 1,428 square feet of Chamberlain flat plate liquid collector subsystem, and a 1500 gallon storage subsystem circulating hot water producing 321 x 10 to the 6th power Btu/Yr (specified) building heating and hot water heating.
Solar heating and hot water system installed at Shoney's Restaurant, North Little Rock, Arkansas
NASA Astrophysics Data System (ADS)
1980-08-01
A solar heating system designed to supply a major portion of the space and water heating requirements for a restaurant is described. The restaurant has a floor space of approximately 4,650 square feet and requires approximate 1500 gallons of hot water daily. The solar energy system consists of 1,428 square feet of Chamberlain flat plate liquid collector subsystem, and a 1500 gallon storage subsystem circulating hot water producing 321 x 10 to the 6th power Btu/Yr (specified) building heating and hot water heating.
NASA Astrophysics Data System (ADS)
Zonenshain, L. P.; Kuzmin, M. I.; Bocharova, N. Yu.
1991-12-01
Intraplate, hot spot related volcanic occurrences do not have a random distribution on the Earth's surface. They are concentrated in two large regions (up to 10,000 km in diameter), the Pacific and the African, and two smaller areas (2000-3000 km in diameter), the Central Asian and the Tasmanian. These regions are considered as manifestations of hot fields in the mantle, whereas the regions lying in between are expressions of cold fields in the mantle. Large-scale anomalies coincide with the hot fields: topographic swells, geoid highs, uplifts of the "asthenospheric table", inferred heated regions in the lowermost mantle according to seismic tomographic images, geochemical anomalies showing the origin of volcanics from undepleted mantle sources. Hot fields are relatively stable features, having remained in the same position on the Earth's surface during the last 120 Ma, although they have other configurations and other positions in the Late Paleozoic and Early Mesozoic. Available data show that two main hot fields (Pacific and African) are possibly moving one with respect to the other, converging along the Eastern Pacific subduction system and diverging along that of the Western Pacific. If so, well-known differences between these subduction systems can also be connected with related displacement of the hot fields. Hot fields are assumed to correspond to upwelling branches of mantle and rather deep mantle convection, and cold fields to downwelling branches. Thus, hot fields can be regarded as expressions of deeper tectonics, comparative to the plate tectonics, which is operating in the upper layers of the Earth. We call it hot-field tectonics. Plate tectonics is responsible for the opening and closure of oceans and for the formation of orogenic belts, whereas hot-field tectonics accounts for a larger cyclicity of the Earth's evolution and for amalgamation and break up of Pangea-type supercontinents. Hot-field tectonics seems to be the only process to have existed on all of the terrestrial planets. We speculate that hot-field tectonics governs the global geodynamics of the Earth.
NASA Astrophysics Data System (ADS)
Oki, Sae; Suzuki, Ryosuke O.
2017-05-01
The performance of a flat-plate thermoelectric (TE) module consisting of square truncated pyramid elements is simulated using commercial software and original TE programs. Assuming that the temperatures of both the hot and cold surfaces are constant, the performance can be varied by changing the element shape and element alignment pattern. When the angle between the edge and the base is 85° and the small square surfaces of all n-type element faces are connected to the low-temperature surface, the efficiency becomes the largest among all the 17 examined shapes and patterns. By changing the shape to match the temperature distribution, the performance of the TE module is maximized.
NASA Astrophysics Data System (ADS)
Meyer, H.
1981-11-01
Flat plate collector systems suitable for hot water supply, swimming pool heating, and auxiliary space heating were developed. A control and ready made packaged pipe assembly, adapted to synthetic fluid, was developed. A heat transfer fluid was selected, pumps, safety devices, armatures and seals were tested for their long term performance. External heat exchangers for simple and cascade arrangement of the hot water tanks were tested. It is found that the channel design of a roll bonded absorber has only limited effect on collector performance if the channel width approximates the space between the plates. Systems already installed work satisfactorily.
Nelson, Sidney [Hudson, OH
2011-02-15
Methods are provided for reducing emission of mercury from a gas stream by treating the gas with carbonaceous mercury sorbent particles to reduce the mercury content of the gas; collecting the carbonaceous mercury sorbent particles on collection plates of a hot-side ESP; periodically rapping the collection plates to release a substantial portion of the collected carbonaceous mercury sorbent particles into hoppers; and periodically emptying the hoppers, wherein such rapping and emptying are done at rates such that less than 70% of mercury adsorbed onto the mercury sorbent desorbs from the collected mercury sorbent into the gas stream.
Hot spot abundance, ridge subduction and the evolution of greenstone belts
NASA Technical Reports Server (NTRS)
Abbott, D.; Hoffman, S.
1986-01-01
A number of plate tectonic hypotheses have been proposed to explain the origin of Archaean and Phanerozoic greenstone/ophiolite terranes. In these models, ophiolites or greenstone belts represent the remnants of one or more of the following: island arcs, rifted continental margins, oceanic crustal sections, and hot spot volcanic products. If plate tectonics has been active since the creation of the Earth, it is logical to suppose that the same types of tectonic processes which form present day ophiolites also formed Archaean greenstone belts. However, the relative importance of the various tectonic processes may well have been different and are discussed.
Radiant Heat Transfer in Reusable Surface Insulation
NASA Technical Reports Server (NTRS)
Hughes, T. A.; Linford, R. M. F.; Chmitt, R. J.; Christensen, H. E.
1973-01-01
During radiant testing of mullite panels, temperatures in the insulation and support structure exceeded those predicted on the basis of guarded hot plate thermal conductivity tests. Similar results were obtained during arc tunnel tests of mullite specimens. The differences between effective conductivity and guarded hot plate values suggested that radiant transfer through the mullite was occurring. To study the radiant transport, measurements were made of the infrared transmission through various insulating materials and fibers of interest to the shuttle program, using black body sources over the range of 780 to 2000 K. Experimental data were analyzed and scattering coefficients were derived for a variety of materials, fiber diameters, and source temperature.
Feng, Jingjie; Zhou, Congcong; He, Cheng; Li, Yuan; Ye, Xuesong
2017-04-01
In this paper, a miniaturized wearable core body temperature (CBT) monitoring system based on the dual heat flux (DHF) principle was developed. By interspersing calcium carbonate powder in PolyDimethylsiloxane (PDMS), a reformative heat transfer medium was produced to reduce the thermal equilibrium time. Besides, a least mean square (LMS) algorithm based active noise cancellation (ANC) method was adopted to diminish the impact of ambient temperature fluctuations. Theoretical analyses, finite element simulation, experiments on a hot plate and human volunteers were performed. The results showed that the proposed system had the advantages of small size, reduced initial time (~23.5 min), and good immunity to fluctuations of the air temperature. For the range of 37-41 °C on the hot plate, the error compared with a Fluke high accuracy thermometer was 0.08 ± 0.20 °C. In the human experiments, the measured temperature in the rest trial (34 subjects) had a difference of 0.13 ± 0.22 °C compared with sublingual temperature, while a significant increase of 1.36 ± 0.44 °C from rest to jogging was found in the exercise trial (30 subjects). This system has the potential for reliable continuous CBT measurement in rest and can reflect CBT variations during exercise.
A Procedure for Evaluation of Dust Potential in Desert Terrains,
1985-01-01
Surficial Deposits, Silt, Clay, Sand. ABSTRACT ^•The evaluation of dust potential in hot deserts is based on the association of well de - fined dust...late Quaternary, which la heat understood, the efectiveaeas of climatic changes and the identification of euch •«ctuatioa in soils may he only roughly...ridges - ballenas . Nahal Roded, southern Arava Valley. „ ’ *m V J c^> ^ Mmmmmmmmmmmmmmmmw iu .......... . ^ ^^ - - _^^_^_m_ mm, PLATE S
Rapid and low-cost hot-embossing of polycaprolactone microfluidic devices
NASA Astrophysics Data System (ADS)
Fan, Yiqiang; Liu, Shicheng; He, Jianyun; Gao, Kexin; Zhang, Yajun
2018-01-01
Polycaprolactone (PCL) is a low-cost biocompatible and biodegradable material which is highly suitable for the short-live applications like microfluidics in the biological and medical field. In this study, a rapid and low-cost microfabrication technique for PCL-based microfluidic devices is proposed, the SU-8 mold fabricated on the silicon substrate was used for the hot-embossing of microstructures on PCL. Since PCL after the molding process is optically non-transparent, to improve the visibility of the fluid in the microfluidic device and enclosing the microchannel, a transparency adhesive film which originally used for the sealing of PCR well-plate is used for the sealing of the microchannels embossed on PCL substrate. The profile of the fabricated microchannels was carefully characterized, the bonding strength is tested and several PCL-based microfluidic devices were also fabricated and tested for demonstration.
NASA Technical Reports Server (NTRS)
Stefanick, M.; Jurdy, D. M.
1984-01-01
Statistical analyses are compared for two published hot spot data sets, one minimal set of 42 and another larger set of 117, using three different approaches. First, the earths surface is divided into 16 equal-area fractions and the observed distribution of hot spots among them is analyzed using chi-square tests. Second, cumulative distributions about the principal axes of the hot spot inertia tensor are used to describe hot spot distribution. Finally, a hot spot density function is constructed for each of the two hot spot data sets. The methods all indicate that hot spots have a nonuniform distribution, even when statistical fluctuations are considered. To the first order, hot spots are concentrated on one half of of the earth's surface area; within that portion, the distribution is consistent with a uniform distribution. The observed hot spot densities for neither data set are explained solely by plate speed.
Solar hot water system installed at Las Vegas, Nevada
NASA Technical Reports Server (NTRS)
1981-01-01
A solar energy hot water system installed in a motor inn at Las Vegas, Nevada is described. The inn is a three story building with a flat roof for installation of the solar panels. The system consists of 1,200 square feet of liquid flat plate collectors, a 2,500 gallon insulated vertical steel storage tank, two heat exchangers, and pumps and controls. The system was designed to supply approximately 74 percent of the total hot water load.
Design Guideline for New Generation of High-Temperature Guarded Hot Plate
NASA Astrophysics Data System (ADS)
Wu, J.; Hameury, J.; Failleau, G.; Blahut, A.; Vachova, T.; Strnad, R.; Krause, M.; Rafeld, E.; Hammerschmidt, U.
2018-02-01
This paper complements the existing measurement standards and literature for high-temperature guarded hot plates (HTGHPs) by addressing specific issues relating to thermal conductivity measurement of technical insulation at high temperatures. The examples given are focused on the designs of HTGHPs for measuring thin thermal insulation. The sensitivity studies have been carried out on major influencing factors that affect the thermal conductivity measurements using HTGHPs, e.g., the uncertainty of temperature measurements, plate flatness and center-guard gap design and imbalance. A new configuration of center-guard gap with triangular shape cross section has been optimized to obtain the same thermal resistance as a 2 mm wide gap with rectangular shape cross section that has been used in the HTGHPs at NPL and LNE. Recommendations have been made on the selections of heater plate materials, high-temperature high-emissivity coatings and miniature temperature sensors. For the first time, thermal stress analysis method has been applied to the field of HTGHPs, in order to estimate the effect of differential thermal expansion on the flatness of thin rigid specimens during thermal conductivity tests in a GHP.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shuja, T.A.
1986-01-01
In this paper an attempt has been made to correlate the tectonic and geologic features with surface manifestations of geothermal activity in Pakistan to delineate prospective areas for exploration and development of geothermal energy. Underthrusting of the Arabian plate beneath the Eurasian plate has resulted in the formation of Chagai volcanic arc which extends into Iran. Quaternary volcanics in this environment, along with the presence of thermal springs, is an important geotectonic feature revealing the possible existence of geothermal fields. Geothermal activity in the northern areas of Pakistan, as evidenced by thermal springs, is the likely result of collision andmore » underthrusting of the Indian plate beneath the Eurasian plate. Numerous hot springs are found along the Main Mantle thrust and the Main Karakorum thrust in Chilas and Hunza areas respectively. The concentration of hot springs in Sind Province is also indicative of geothermal activity. A string of thermal seepages and springs following the alignment of the Syntaxial Bend in Punjab Province is also noteworthy from the geothermal viewpoint. In Baluchistan Province (southwest Pakistan), Hamun-e-Mushkel, a graben structure, also shows geothermal prospects on the basis of aeromagnetic studies.« less
The transference of heat from a hot plate to an air stream
NASA Technical Reports Server (NTRS)
Elias, Franz
1931-01-01
The object of the present study was to define experimentally the field of temperature and velocity in a heated flat plate when exposed to an air stream whose direction is parallel to it, then calculate therefrom the heat transference and the friction past the flat plate, and lastly, compare the test data with the mathematical theory. To ensure comparable results, we were to actually obtain or else approximate: a) two-dimensional flow; b) constant plate temperature in the direction of the stream. To approximate the flow in two dimensions, we chose a relatively wide plate and measured the velocity and temperature in the median plane.
Using a Photon Beam for Thermal Nociceptive Threshold Experiments
NASA Astrophysics Data System (ADS)
Walker, Azida; Anderson, Jeffery; Sherwood, Spencer
In humans, risk of diabetes and diabetic complications increases with age and duration of prediabetic state. In an effort to understand the progression of this disease scientists have evaluated the deterioration of the nervous system. One of the current methods used in the evaluation of the deterioration of the nervous system is through thermal threshold experiments. An incremental Hot / Cold Plate Analgesia Meter (IITC Life Science,CA is used to linearly increase the plate temperature at a rate of 10 ºC min-1 with a cutoff temperature of 55 ºC. Hind limb heat pain threshold (HPT) will be defined as a plate temperature at which the animal abruptly withdraws either one of its hind feet from the plate surface in a sharp move, typically followed by licking of the lifted paw. One of the disadvantages of using this hot plate method is in determining the true temperature at which the paw was withdrawn. While the temperature of the plate is known the position of the paw on the surface may vary; occasionally being cupped resulting in a temperature differentiation between the plate and the paw. During experiments the rats may urine onto the plate changing the temperature of the surface again resulting in reduced accuracy as to the withdrawal threshold. We propose here a new method for nociceptive somatic experiments involving the heat pain threshold experiments. This design employs the use of a photon beam to detect thermal response from an animal model. The details of this design is presented. Funded by the Undergraduate Research Council at the University of Central Arkansas.
Laser Induced Forced Motion and Stress Waves in Plates and Shells.
1981-08-01
the plate at the center, normal to the plate surface. The Laser used was a Holobeam model 630-QNd glass system. This Laser produces an output power (in...V o 0 0 I lue ceill I Ii 1)r1 i 11im and hot nchary\\ cond i t i ons S or tile i n it i aI I St ate toget her with ji(. 38c ) iiav he u ISed to
Crack-Free, Nondistorting Can For Hot Isostatic Pressing
NASA Technical Reports Server (NTRS)
Juhas, John J.
1991-01-01
New method of canning specimens made of composites of arc-sprayed and plasma-sprayed tape reduces outgassing and warping during hot isostatic pressing. Produces can having reliable, crack-free seal and thereby helps to ensure pressed product of high quality. Specimen placed in ring of refractory metal between two face sheets, also of refractory metal. Assembly placed in die in vacuum hot press, where simultaneously heated and pressed until plates become diffusion-welded to ring, forming sealed can around specimen. Specimen becomes partially densified, and fits snugly within can. Ready for further densification by hot isostatic pressing.
Zhou, Haijian; Wang, Huanxin; Xu, Ying; Zhao, Mingqiang; Guan, Hong; Li, Machao; Shao, Zhujun
2013-01-01
Background Legionella is the causative agent of Legionnaires' disease, and hot springs are a major source of outbreaks of this disease. It is important from a public health perspective to survey hot spring environments for the presence of Legionella. Methods Prospective surveillance of the extent of Legionella pollution was conducted at three hot spring recreational areas in Beijing, China in 2011. Pulsed-field gel electrophoresis (PFGE) and sequence-based typing (SBT) were used to describe the genetic polymorphism of isolates. The intracellular growth ability of the isolates was determined by interacting with J774 cells and plating the dilutions onto BCYE agar plates. Results Overall, 51.9% of spring water samples showed Legionella-positive, and their concentrations ranged from 1 CFU/liter to 2,218 CFU/liter. The positive rates of Legionella were significantly associated with a free chlorine concentration of ≥0.2 mg/L, urea concentration of ≥0.05 mg/L, total microbial counts of ≥400 CFU/ml and total coliform of ≥3 MPN/L (p<0.01). The Legionella concentrations were significantly associated with sample temperature, pH, total microbial counts and total coliform (p<0.01). Legionella pneumophila was the most frequently isolated species (98.9%), and the isolated serogroups included serogroups 3 (25.3%), 6 (23.4%), 5 (19.2%), 1 (18.5%), 2 (10.2%), 8 (0.4%), 10 (0.8%), 9 (1.9%) and 12 (0.4%). Two hundred and twenty-eight isolates were analyzed by PFGE and 62 different patterns were obtained. Fifty-seven L. pneumophila isolates were selected for SBT analysis and divided into 35 different sequence types with 5 main clonal groups. All the 57 isolates had high intracellular growth ability. Conclusions Our results demonstrated high prevalence and genetic polymorphism of Legionella in springs in Beijing, China, and the SBT and intracellular growth assay results suggested that the Legionella isolates of hot spring environments were pathogenic. Improved control and prevention strategies are urgently needed. PMID:23527075
DOE Office of Scientific and Technical Information (OSTI.GOV)
Crapps, Justin M.; Clarke, Kester D.; Katz, Joel D.
2012-06-06
We use experimentation and finite element modeling to study a Hot Isostatic Press (HIP) manufacturing process for U-10Mo Monolithic Fuel Plates. Finite element simulations are used to identify the material properties affecting the process and improve the process geometry. Accounting for the high temperature material properties and plasticity is important to obtain qualitative agreement between model and experimental results. The model allows us to improve the process geometry and provide guidance on selection of material and finish conditions for the process strongbacks. We conclude that the HIP can must be fully filled to provide uniform normal stress across the bondingmore » interface.« less
Holding fixture for a hot stamping press
NASA Technical Reports Server (NTRS)
Harris, R. P. (Inventor)
1983-01-01
A hand held guide for manually positioning a work piece between the anvil rib and tool of a hot die stamping press is described. A groove completed by interchangeable cover plates attached at one end of the guide conforms to a cross sectional dimension common to similar workpieces and, with a force fit, retentively holds each of the workpieces.
Code of Federal Regulations, 2014 CFR
2014-01-01
... classification under this part. “B” branded. Branding with a hot iron the letter “B” high on the left hip near... semen plasma test, and the standard plate test. Dairy cattle. All cattle, regardless of age or sex or... and the Veterinarian in Charge; and (b)(1) Permanently identified by a “V” hot brand high on the hip...
DOT National Transportation Integrated Search
1996-09-27
This research has shown that a Grade 70 construction steel of 1/2- to 1-inch plate thicknesses can be produced without a quench and temper or accelerated cooling from hot-rolling if the Cu content in the steel is sufficiently high. Coherent very fine...
Solar hot water system installed at Anderson, South Carolina
NASA Technical Reports Server (NTRS)
1978-01-01
A description is given of the solar energy hot water system installed in the Days Inns of America, Inc., at Anderson, South Carolina. The building is a low-rise, two-story 114-room motel. The solar system was designed to provide 40 percent of the total hot water demand. The collector is a flat plate, liquid with an area of 750 square feet. Operation of this system was begun in November 1977, and has performed flawlessly for one year.
Evaluation of the surface strength of glass plates shaped by hot slumping process
NASA Astrophysics Data System (ADS)
Proserpio, L.; Crimi, G.; Ghigo, M.; Pareschi, G.; Salmaso, B.; D'Este, A.; Dall'Igna, R.; Silvestri, M.; Parodi, G.; Martelli, F.
2013-09-01
The Hot Slumping Technology is under development by several research groups in the world for the realization of X-ray segmented mirrors, based on thin glass plates: during the process of slumping, a glass foil is shaped over a mould at temperatures above its transformation point. The performed thermal cycle and related operations might have effects on the strength characteristics of the glass, with consequences on the structural design of the elemental optical module and consecutively on the whole X-ray telescope. No reference technical literature exists for this particular aspect since the strength of glass depends on several parameters connected to any of the manufacturing and glass history stages, such as the distribution of surface flaws or the residual internal stresses. It is therefore extremely important to test the mechanical strength of the glass plates after they underwent the slumping process. The Astronomical Observatory of Brera (INAFOAB, Merate - Italy) started a deep analysis of this aspect, with the collaboration of Stazione Sperimentale del Vetro (SSV, Murano - Italy) and BCV Progetti (Milano - Italy). The entire study has been realized on borosilicate glass D263 by Schott, largely considered for the realization of next-generation IXO-like X-ray telescope. More than 200 slumped plates of dimension 100 mm x 100 mm and thickness 0.4 mm, both flat and curved, have been produced and tested; the collected experimental data have been compared to non-linear FEM analyses and treated with Weibull statistics, giving the strength data necessary to assess the current IXO glass X-ray telescope design, in terms of survival probability, when subject to static and acoustic load characteristic of the launch phase. The paper describes the activities performed and presents the obtained results.
Zhang, Tao; Li, Lei; Lu, Shi-Hong; Gong, Hai; Wu, Yun-Xin
2018-01-01
Asymmetrical shear rolling with velocity asymmetry and geometry asymmetry is beneficial to enlarge deformation and refine grain size at the center of the thick plate compared to conventional symmetrical rolling. Dynamic recrystallization (DRX) plays a vital role in grain refinement during hot deformation. Finite element models (FEM) coupled with microstructure evolution models and cellular automata models (CA) are established to study the microstructure evolution of plate during asymmetrical shear rolling. The results show that a larger DRX fraction and a smaller average grain size can be obtained at the lower layer of the plate. The DRX fraction at the lower part increases with the ascending speed ratio, while that at upper part decreases. With the increase of the offset distance, the DRX fraction slightly decreases for the whole thickness of the plate. The differences in the DRX fraction and average grain size between the upper and lower surfaces increase with the ascending speed ratio; however, it varies little with the change of the speed ratio. Experiments are conducted and the CA models have a higher accuracy than FEM models as the grain morphology, DRX nuclei, and grain growth are taken into consideration in CA models, which are more similar to the actual DRX process during hot deformation. PMID:29342080
Waite, Gregory P.; Schutt, D.L.; Smith, Robert B.
2005-01-01
Teleseismic shear wave splitting measured at 56 continuous and temporary seismographs deployed in a 500 km by 600 km area around the Yellowstone hot spot indicates that fast anisotropy in the mantle is parallel to the direction of plate motion under most of the array. The average split time from all stations of 0.9 s is typical of continental stations. There is little evidence for plume-induced radial strain, suggesting that any contribution of gravitationally spreading plume material is undetectably small with respect to the plate motion velocity. Two stations within Yellowstone have splitting measurements indicating the apparent fast anisotropy direction (ϕ) is nearly perpendicular to plate motion. These stations are ∼30 km from stations with ϕ parallel to plate motion. The 70° rotation over 30 km suggests a shallow source of anisotropy; however, split times for these stations are more than 2 s. We suggest melt-filled, stress-oriented cracks in the lithosphere are responsible for the anomalous ϕ orientations within Yellowstone. Stations southeast of Yellowstone have measurements of ϕ oriented NNW to WNW at high angles to the plate motion direction. The Archean lithosphere beneath these stations may have significant anisotropy capable of producing the observed splitting.
Zhang, Tao; Li, Lei; Lu, Shi-Hong; Gong, Hai; Wu, Yun-Xin
2018-01-17
Asymmetrical shear rolling with velocity asymmetry and geometry asymmetry is beneficial to enlarge deformation and refine grain size at the center of the thick plate compared to conventional symmetrical rolling. Dynamic recrystallization (DRX) plays a vital role in grain refinement during hot deformation. Finite element models (FEM) coupled with microstructure evolution models and cellular automata models (CA) are established to study the microstructure evolution of plate during asymmetrical shear rolling. The results show that a larger DRX fraction and a smaller average grain size can be obtained at the lower layer of the plate. The DRX fraction at the lower part increases with the ascending speed ratio, while that at upper part decreases. With the increase of the offset distance, the DRX fraction slightly decreases for the whole thickness of the plate. The differences in the DRX fraction and average grain size between the upper and lower surfaces increase with the ascending speed ratio; however, it varies little with the change of the speed ratio. Experiments are conducted and the CA models have a higher accuracy than FEM models as the grain morphology, DRX nuclei, and grain growth are taken into consideration in CA models, which are more similar to the actual DRX process during hot deformation.
Thermal baffle for fast-breeder reacton
Rylatt, John A.
1977-01-01
A liquid-metal-cooled fast-breeder reactor includes a bridge structure for separating hot outlet coolant from relatively cool inlet coolant consisting of an annular stainless steel baffle plate extending between the core barrel surrounding the core and the thermal liner associated with the reactor vessel and resting on ledges thereon, there being inner and outer circumferential webs on the lower surface of the baffle plate and radial webs extending between the circumferential webs, a stainless steel insulating plate completely covering the upper surface of the baffle plate and flex seals between the baffle plate and the ledges on which the baffle plate rests to prevent coolant from washing through the gaps therebetween. The baffle plate is keyed to the core barrel for movement therewith and floating with respect to the thermal liner and reactor vessel.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-01-08
... measuring at least 10 times the thickness. Universal mill plate (i.e., flat-rolled products rolled on four... determinations. If the Department chooses as facts available a calculated dumping margin from the investigation... questionnaire. See Certain Cut-to-Length Carbon-Quality Steel Plate Products from the Republic of Korea: Final...
Investigating Convective Heat Transfer with an Iron and a Hairdryer
ERIC Educational Resources Information Center
Gonzalez, Manuel I.; Lucio, Jesus H.
2008-01-01
A simple experimental set-up to study free and forced convection in undergraduate physics laboratories is presented. The flat plate of a domestic iron has been chosen as the hot surface, and a hairdryer is used to generate an air stream around the plate. Several experiments are proposed and typical numerical results are reported. An analysis and…
Age-Distance Relations along the Hawaiian-Emperor Volcanic Chain: History and Current Status
NASA Astrophysics Data System (ADS)
Clague, D. A.
2016-12-01
The increase in age with distance along the Hawaiian-Emperor volcanic chain is a key parameter in models of plate motions and mantle dynamics. Wilson (1963) proposed that the Hawaiian Islands formed sequentially as the Pacific Plate migrated over a hot spot in the Earth's mantle based on the inferred increase in age of the Islands to the west. Morgan (1971) proposed that Wilson's hot spot was a geographically fixed mantle plume originating at the core-mantle boundary, and that the orientation and age-distance relations of the chain provided a measure of absolute plate motion with the bend between the Hawaiian and Emperor chains reflecting a major change in motion of the Pacific Plate at 40 Ma. Defining and refining the age relations along the two chains has taken decades due largely to the remoteness of most of the chain, the difficulties in dating altered submarine lavas, and the presence of glacial debris as far south as 42°25'N in the Emperor Seamounts. Ocean drilling program legs 55 and 197 focused on the age and paleolatitude of Emperor Seamounts. Many of the early ages are K-Ar dates. Later dates are Ar/Ar incremental heating extractions of whole-rocks or, more recently still, of clean mineral separates that yield accurate and precise dates (e.g., Sharp and Clague, 2006). Many reported ages have ill-defined errors, especially those of tholeiitic shield lavas. Over-interpretation of the collected age data seemed to indicate coeval volcanism along large segments of the chain, instead of recognizing the errors inherent in many of the determined ages. Subsequent work, such as at Gardner Pinnacles, has eliminated some of these apparent non-linear age relations. The bend is now recognized as a gradual transition in orientation that occurred between 50 and 42 Ma (Sharp & Clague, 2006); it likely resulted from the collision of India and Eurasia that precipitated a worldwide chain reaction of relative and absolute plate motion changes (Dalrymple & Clague, 1976).
Miranda, Hugo F; Noriega, Viviana; Zanetta, Pilar; Prieto, Juan Carlos; Prieto-Rayo, Juan Carlos; Aranda, Nicolás; Sierralta, Fernando
2014-07-15
Opioids have been used for the management of pain and coadministration of two opioids may induce synergism. In a model of tonic pain, the acetic acid writhing test and in a phasic model, the hot plate, the antinociceptive interaction between fentanyl, methadone, morphine, and tramadol was evaluated. The potency of opioids in the writhing test compared to the hot plate assay was from 2.5 (fentanyl) to 15.5 (morphine) times, respectively. The ED50 was used in a fixed ratio for each of the six pairs of opioid combinations, which, resulted in a synergistic antinociception except for methadone/tramadol and fentanyl/tramadol which were additive, in the hot plate. The opioid antagonists naltrexone, naltrindole and nor-binaltorphimine, suggests that the synergism of morphine combinations are due to the activation of MOR subtypes with partially contribution of DOR and KOR, however fentanyl and methadone combinations are partially due to the activation of MOR and DOR subtypes and KOR lack of participation. The antinociceptive effects of tramadol combinations, are partially due to the activation of MOR, DOR and KOR opioid subtypes. These results suggets that effectiveness and magnitude of the interactions between opioids are dependent on pain stimulus intensity.
2014-01-01
Background Opioids have been used for the management of pain and coadministration of two opioids may induce synergism. In a model of tonic pain, the acetic acid writhing test and in a phasic model, the hot plate, the antinociceptive interaction between fentanyl, methadone, morphine, and tramadol was evaluated. Results The potency of opioids in the writhing test compared to the hot plate assay was from 2.5 (fentanyl) to 15.5 (morphine) times, respectively. The ED50 was used in a fixed ratio for each of the six pairs of opioid combinations, which, resulted in a synergistic antinociception except for methadone/tramadol and fentanyl/tramadol which were additive, in the hot plate. The opioid antagonists naltrexone, naltrindole and nor-binaltorphimine, suggests that the synergism of morphine combinations are due to the activation of MOR subtypes with partially contribution of DOR and KOR, however fentanyl and methadone combinations are partially due to the activation of MOR and DOR subtypes and KOR lack of participation. The antinociceptive effects of tramadol combinations, are partially due to the activation of MOR, DOR and KOR opioid subtypes. Conclusion These results suggets that effectiveness and magnitude of the interactions between opioids are dependent on pain stimulus intensity. PMID:25017386
El-Mallah, Ahmed; Aboul-Ela, Maha; Ellakany, Abdalla
2017-01-01
Papaver libanoticum is an endemic plant to Lebanese region (family Papaveraceae) that has not been investigated before. The present study aimed to explore the analgesic activity of dried ethanolic extract of Papaver libanoticum (PLE) using tail flick, hot plate, and acetic acid induced writhing models in mice. The involvement of opioid receptors in the analgesic mechanism was investigated using naloxone antagonism. Results demonstrated that PLE exhibited a potent dose dependent analgesic activity in all tested models for analgesia. The analgesic effect involved activation of opioid receptors in the central nervous system, where both spinal and supraspinal components might be involved. The time course for analgesia revealed maximum activity after three hours in both tail flick and hot plate methods, which was prolonged to 24 hours. Metabolites of PLE could be responsible for activation of opioid receptors. The EC50 of PLE was 79 and 50 mg/kg in tail flick and hot plate tests, respectively. The total coverage of analgesia by PLE was double that of morphine in both tests. In conclusion, PLE proved to have opioid agonistic activity with a novel feature of slow and prolonged effect. The present study could add a potential tool in the armaments of opioid drugs as a natural potent analgesic and for treatment of opioid withdrawal syndrome. PMID:28280516
Hijazi, Mohamad Ali; El-Mallah, Ahmed; Aboul-Ela, Maha; Ellakany, Abdalla
2017-01-01
Papaver libanoticum is an endemic plant to Lebanese region (family Papaveraceae) that has not been investigated before. The present study aimed to explore the analgesic activity of dried ethanolic extract of Papaver libanoticum (PLE) using tail flick, hot plate, and acetic acid induced writhing models in mice. The involvement of opioid receptors in the analgesic mechanism was investigated using naloxone antagonism. Results demonstrated that PLE exhibited a potent dose dependent analgesic activity in all tested models for analgesia. The analgesic effect involved activation of opioid receptors in the central nervous system, where both spinal and supraspinal components might be involved. The time course for analgesia revealed maximum activity after three hours in both tail flick and hot plate methods, which was prolonged to 24 hours. Metabolites of PLE could be responsible for activation of opioid receptors. The EC50 of PLE was 79 and 50 mg/kg in tail flick and hot plate tests, respectively. The total coverage of analgesia by PLE was double that of morphine in both tests. In conclusion, PLE proved to have opioid agonistic activity with a novel feature of slow and prolonged effect. The present study could add a potential tool in the armaments of opioid drugs as a natural potent analgesic and for treatment of opioid withdrawal syndrome.
Amabeoku, George J; Kabatende, Joseph
2012-01-01
Leaf methanol extract of C. orbiculata L. was investigated for antinociceptive and anti-inflammatory activities using acetic acid writhing and hot-plate tests and carrageenan-induced oedema test in mice and rats, respectively. C. orbiculata (100-400 mg/kg, i.p.) significantly inhibited acetic acid-induced writhing and significantly delayed the reaction time of mice to the hot-plate-induced thermal stimulation. Paracetamol (300 mg/kg, i.p.) significantly inhibited the acetic acid-induced writhing in mice. Morphine (10 mg/kg, i.p.) significantly delayed the reaction time of mice to the thermal stimulation produced with hot plate. Leaf methanol extract of C. orbiculata (50-400 mg/kg, i.p.) significantly attenuated the carrageenan-induced rat paw oedema. Indomethacin (10 mg/kg, p.o.) also significantly attenuated the carrageenan-induced rat paw oedema. The LD(50) value obtained for the plant species was greater than 4000 mg/kg (p.o.). The data obtained indicate that C. orbiculata has antinociceptive and anti-inflammatory activities, justifying the folklore use of the plant species by traditional medicine practitioners in the treatment of painful and inflammatory conditions. The relatively high LD(50) obtained shows that C. orbiculata may be safe in or nontoxic to mice.
NASA Astrophysics Data System (ADS)
Ning, Fangkun; Jia, Weitao; Hou, Jian; Chen, Xingrui; Le, Qichi
2018-05-01
Various fracture criteria, especially Johnson and Cook (J-C) model and (normalized) Cockcroft and Latham (C-L) criterion were contrasted and discussed. Based on normalized C-L criterion, adopted in this paper, FE simulation was carried out and hot rolling experiments under temperature range of 200 °C–350 °C, rolling reduction rate of 25%–40% and rolling speed from 7–21 r/min was implemented. The microstructure was observed by optical microscope and damage values of simulation results were contrasted with the length of cracks on diverse parameters. The results show that the plate generated less edge cracks and the microstructure emerged slight shear bands and fine dynamic recrystallization grains rolled at 350 °C, 40% reduction and 14 r/min. The edge cracks pre-criterion model was obtained combined with Zener-Hollomon equation and deformation activation energy.
High loading uranium fuel plate
Wiencek, Thomas C.; Domagala, Robert F.; Thresh, Henry R.
1990-01-01
Two embodiments of a high uranium fuel plate are disclosed which contain a meat comprising structured uranium compound confined between a pair of diffusion bonded ductile metal cladding plates uniformly covering the meat, the meat having a uniform high fuel loading comprising a content of uranium compound greater than about 45 Vol. % at a porosity not greater than about 10 Vol. %. In a first embodiment, the meat is a plurality of parallel wires of uranium compound. In a second embodiment, the meat is a dispersion compact containing uranium compound. The fuel plates are fabricated by a hot isostatic pressing process.
Dielectric characterization of hot-mix asphalt at the smart road using GPR
NASA Astrophysics Data System (ADS)
Al-Qadi, Imad L.; Loulizi, A.; Lahouar, S.
2000-04-01
To better interpret collected ground penetrating radar (GPR) data, a project is currently underway at the Virginia Smart Road. Twelve different flexible pavement sections and a continuously reinforced concrete rigid pavement section are incorporated in the road design. Thirty-five copper plates were placed at different layer interfaces throughout the pavement sections. The copper plates serve as a reflecting material and thus allow the determination of layers' dielectric constant over the GPR frequency range. An initial development of a method to calculate the complex dielectric constant of hot-mix asphalt over the frequency range of 750 to 1750 MHz using an air-coupled GPR system is presented. Utilizing GPR data, this method will be used to predict changes of the dielectric properties of the different SuperPaveTM mixes used at the Smart Road over time. The method is based on equating the overall reflection coefficient as obtained from the radar measurements with the calculated reflection coefficient using electromagnetic theory. The measured overall reflection coefficient is obtained by dividing the reflected frequency spectrum over the incident one. The theoretical overall reflection coefficient is obtained using the multiple reflection model. A Gauss-Newton method is then used to solve for the complex dielectric constant.
NASA Astrophysics Data System (ADS)
Park, Y.; Eriksson, N.; Newell, R.; Keiser, D. D.; Sohn, Y. H.
2016-11-01
Eutectoid decomposition of γ-phase (cI2) into α-phase (oC4) and γ‧-phase (tI6) during the hot isostatic pressing (HIP) of the U-10 wt% Mo (U10Mo) alloy was investigated using monolithic fuel plate samples consisting of U10Mo fuel alloy, Zr diffusion barrier and AA6061 cladding. The decomposition of the γ-phase was observed because the HIP process is carried out near the eutectoid temperature, 555 °C. Initially, a cellular structure, consisting of γ‧-phase surrounded by α-phase, developed from the destabilization of the γ-phase. The cellular structure further developed into an alternating lamellar structure of α- and γ‧-phases. Using scanning electron microscopy and transmission electron microscopy, qualitative and quantitative microstructural analyses were carried out to identify the phase constituents, and elucidate the microstructural development based on time-temperature-transformation diagram of the U10Mo alloy. The destabilization of γ -phase into α- and γ‧-phases would be minimized when HIP process was carried out with rapid ramping/cooling rate and dwell temperature higher than 560 °C.
Method for Measuring Thermal Conductivity of Small Samples Having Very Low Thermal Conductivity
NASA Technical Reports Server (NTRS)
Miller, Robert A.; Kuczmarski, Maria a.
2009-01-01
This paper describes the development of a hot plate method capable of using air as a standard reference material for the steady-state measurement of the thermal conductivity of very small test samples having thermal conductivity on the order of air. As with other approaches, care is taken to ensure that the heat flow through the test sample is essentially one-dimensional. However, unlike other approaches, no attempt is made to use heated guards to block the flow of heat from the hot plate to the surroundings. It is argued that since large correction factors must be applied to account for guard imperfections when sample dimensions are small, it may be preferable to simply measure and correct for the heat that flows from the heater disc to directions other than into the sample. Experimental measurements taken in a prototype apparatus, combined with extensive computational modeling of the heat transfer in the apparatus, show that sufficiently accurate measurements can be obtained to allow determination of the thermal conductivity of low thermal conductivity materials. Suggestions are made for further improvements in the method based on results from regression analyses of the generated data.
Discipline-based planetary education research and computational fluid dynamics analysis of Mars
NASA Astrophysics Data System (ADS)
Coba, Filis
This thesis originates from the testing and implementation of an IRB-approved interactive animation designed to help students understand what causes The Reasons For The Seasons (RFTS) on Earth. Results from the testing indicated a small improvement in student understanding after exposure to the animation. Next, using the 3-D mapping tool Google Earth, students explored seasons and other planetary features on Mercury, Venus, the Moon and Mars through IRB-approved interactive tours which were developed and tested for astronomy education. Results from the tests indicated that there were statistically significant learning gains (p-value < 0.05) after students interacted with the tours compared to those who did not. The development of the tours inspired a geophysics study of the possibility of former plate motion (or plate tectonics) on Mars. A 2-D finite element convection model for the mantle of Mars was designed and solved using COMSOL Multiphysics 5.1, to investigate whether or not thermal gradients in a Mars-sized planet could cause vigorous upper mantle convection, consistent with plate tectonic processes. Results from this project indicated that stable convection could occur in the interior of a Mars-like planet assuming the presence of sufficiently high thermal gradients at about 0.8 times the mantle temperature of Earth. The convective patterns resembled hot upwelling and cool downwelling which may be similar to subduction-like features. Furthermore, increasing the temperature of the hot boundaries resulted in faster, more rigorous convective motions and a hotter average temperature.
Polymeric and composite materials for use in systems utilizing hot, flowing geothermal brine. II
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lorensen, L.E.; Walkup, C.M.
1978-04-13
Further progress is reported on a continuing experimental program designed to select high-performance polymeric materials for use in geothermal power plants. In field tests 12 nozzles, 27 wear plates, and 2 types of polymer lined pipe were tested. Nozzles made of Teflons TFE and PFA, Tefzel, Ryton PPS and H-Resin/carbon cloth were little changed except for some scaling. The fluorocarbons scaled least rapidly. All blade type wear plates eroded, those based on Tefzel, PPQ, and PPS the least. Fluorocarbon lined pipes were little affected by exposure. In laboratory tests samples were heated at 250 and 300/sup 0/C in brine. Severalmore » materials including fluorocarbon and unhydrolyzable aromatic or cross-linked aliphatic, thermally stable polymers survived for periods up to 1300 h. In erosion tests, coatings based on epoxy resins and a fluorocarbon were most resistant; good adhesion was required.« less
One-year assessment of a solar space/water heater--Clinton, Mississippi
NASA Technical Reports Server (NTRS)
1981-01-01
Unit called "System 4" integrated into space-heating and hot-water systems of dormitory satisfied 32 percent of building heat load. System 4 includes flat-plate air collectors, circulation blowers, rock storage bed with heat exchanger, two hot water tanks, and auxiliary heaters. Report describes performance of system and subsystems, operating-energy requirements and savings, and performance parameters.
NASA Technical Reports Server (NTRS)
1978-01-01
The solar panels pictured below, mounted on a Moscow, Idaho home, are part of a domestic hot water heating system capable of providing up to 100 percent of home or small business hot water needs. Produced by Lennox Industries Inc., Marshalltown, Iowa, the panels are commercial versions of a collector co-developed by NASA. In an effort to conserve energy, NASA has installed solar collectors at a number of its own facilities and is conducting research to develop the most efficient systems. Lewis Research Center teamed with Honeywell Inc., Minneapolis, Minnesota to develop the flat plate collector shown. Key to the collector's efficiency is black chrome coating on the plate developed for use on spacecraft solar cells, the coating prevents sun heat from "reradiating," or escaping outward. The design proved the most effective heat absorber among 23 different types of collectors evaluated in a Lewis test program. The Lennox solar domestic hot water heating system has three main components: the array of collectors, a "solar module" (blue unit pictured) and a conventional water heater. A fluid-ethylene glycol and water-is circulated through the collectors to absorb solar heat. The fluid is then piped to a double-walled jacket around a water tank within the solar module.
Planform structure of turbulent Rayleigh-Benard convection
DOE Office of Scientific and Technical Information (OSTI.GOV)
Theerthan, S.A.; Arakeri, J.H.
The planform structure of turbulent Rayleigh-Benard convection is obtained from visualizing a liquid crystal sheet stuck to the bottom hot surface. The bottom plate of the convection cell is Plexiglas and the top plate is glass. Water is the test liquid and the Rayleigh number is 4 [times] 10[sup 7]. The planform pattern reveals randomly moving hot streaks surrounded by cold regions suggesting that turbulent Rayleigh-Benard convection is dominated by quasi-two-dimensional randomly moving plumes. Simultaneous temperature traces from two vertically separated thermocouples indicate that these plumes may be inclined forward in the direction of horizontal motion. The periodic eruption ofmore » thermals observed by Sparrow et al and which forms the basis of Howard's model is not observed.« less
A model for correlating flat plate film cooling effectiveness for rows of round holes
NASA Astrophysics Data System (ADS)
Lecuyer, M. R.; Soechting, F. O.
1985-09-01
An effective method of cooling, that has found widespread application in aircraft gas turbines, is the injection of a film of cooling air through holes into the hot mainstream gas to provide a buffer layer between the hot gas and the airfoil surface. Film cooling has been extensively investigated and the results have been reported in the literature. However, there is no generalized method reported in the literature to predict the film cooling performance as influenced by the major variables. A generalized film cooling correlation has been developed, utilizing data reported in the literature, for constant velocity and flat plate boundary layer development. This work provides a basic understanding of the complex interaction of the major variables effecting film cooling performance.
Development of a Woven-Grid Quasi-Bipolar Battery
NASA Technical Reports Server (NTRS)
Tokumaru, P.; Rippel, W.; Zambrano, T.
1998-01-01
This report describes an analytical and experimental investigation of AeroVironment's Quasi-Bipolar battery concept. The modelling/battery design part of the study demonstrates that there is a trade-off between thermal and specified electrical performance. Even so, quasi-bipolar batteries can be designed, with ten times better thermal uniformity, that meet or exceed current state-of-the-art hybrid-electric vehicle battery pack performance, even using the same active materials. The thermal uniformity, power, and energy for these quasi-bipolar battery packs is projected to be very good. The experimental part of the investigation demonstrates the concept of the quasi-bipolar plate applied to a lead foil current collector wrapping around two sides of an inexpensive plastic film core. Approximately 50 quasi-biplate samples were fabricated using a hot laminating press. Hot lamination with "texture" between the plastic and lead shows some promise as a low cost method for fabricating the plates. Five of these plates were assembled into two cells plus one two-cell battery. Data from these test cells were compared with existing data for similar true bipolar batteries. The positive side of the plates exhibited corrosion where not protected by the active material.
Woven-grid sealed quasi-bipolar lead-acid battery construction and fabricating method
NASA Technical Reports Server (NTRS)
Rippel, Wally E. (Inventor)
1989-01-01
A quasi-bipolar lead-acid battery construction includes a plurality of bipolar cells disposed in side-by-side relation to form a stack, and a pair of monoplanar plates at opposite ends of the stack, the cell stack and monopolar plates being contained within a housing of the battery. Each bipolar cell is loaded with an electrolyte and composed of a bipolar electrode plate and a pair of separator plates disposed on opposite sides of the electrode plate and peripherally sealed thereto. Each bipolar electrode plate is composed of a partition sheet and two bipolar electrode elements folded into a hairpin configuration and applied over opposite edges of the partition sheet so as to cover the opposite surfaces of the opposite halves thereof. Each bipolar electrode element is comprised of a woven grid with a hot-melt strip applied to a central longitudinal region of the grid along which the grid is folded into the hairpin configuration, and layers of negative and positive active material pastes applied to opposite halves of the grid on opposite sides of the central hot-melt strip. The grid is made up of strands of conductive and non-conductive yarns composing the respective transverse and longitudinal weaves of the grid. The conductive yarn has a multi-stranded glass core surrounded and covered by a lead sheath, whereas the non-conductive yarn has a multi-stranded glass core surrounded and covered by a thermally activated sizing.
Geodynamic model for the development of the Cameroon Hot Line (Equatorial Africa)
NASA Astrophysics Data System (ADS)
Nkono, Collin; Féménias, Olivier; Demaiffe, Daniel
2014-12-01
This work proposes a new geodynamic model for the development of the Cameroon Hot Line (CHL) in Equatorial Africa. It is based on the analysis of the distribution of lineaments and of magmatic bodies (Paleogene anorogenic ring-complexes and Neogene volcanic centres). Two successive geodynamic models are proposed to explain the distribution of the Cainozoic to recent magmatic activity. They are both sinistral. The first one, during the Paleogene, developed around the N ∼ 70°E direction while the second one (Neogene) is oriented around the N ∼ 130°E direction. The two periods are separated by a short transition. The emplacement follows the local reactivation of pre-existing (Pan-African) faults in relation to the collision between the Afro-Arabian and Eurasian plates, during the Alpine history.
A central solar domestic hot water system - Performance and economic analysis
NASA Astrophysics Data System (ADS)
Wolf, D.; Tamir, A.; Kudish, A. I.
1980-02-01
A solar-assisted central hot water system was retrofitted onto one of the student dormitory complexes. The system consisted of twenty commercial solar collectors, of the pipe and plate type, and central hot water tank connected to two dormitory buildings. The system has two loops: (1) a solar loop, in which the heated water circulates between the collector panels and the central hot water tank, and (2) a consumer loop, where the solar-heated water circulates between the central hot water tank and the dormitory. The solar-heated water circulates through the individual electric hot water tanks which serve as individual hot water storage and booster units, and the mains water is introduced at the bottom of the central tank to replace consumed water. The description of the system, the design and its performance, together with an economic analysis, are presented.
Solar hot water system installed at Days Inn Motel, Jacksonville, Florida
NASA Technical Reports Server (NTRS)
1980-01-01
The solar system was designed to provide 65 percent of the hot water demand. Water in the liquid flat plate collector (900 square feet) system automatically drains into the 1000 gallon lined and vented steel storage tank when the pump is not running. Heat is transferred from storage to Domestic Hot Water (DHW) tanks through a tube and shell heat exchanger. A circulating pump between the DHW tanks and heat exchanger enables solar heated water to help make up DHW standby losses. All pumps are controlled by differential temperature.
Solar domestic hot water system installed at Texas City, Texas
NASA Technical Reports Server (NTRS)
1980-01-01
This is the final technical report of the solar energy system located at LaQuinta Motor Inn, Texas City, Texas. The system was designed to supply 63 percent of the total hot water load for a new 98 unit motor inn. The solar energy system consists of a 2100 square feet Raypack liquid flat plate collector subsystem and a 2500 gallon storage subsystem circulating hot water producing 3.67 x 10 to the 8th power Btu/year. Abstracts from the site files, specification references, drawings, installation, operation, and maintenance instructions are included.
NASA Astrophysics Data System (ADS)
Yamaura, S.; Yokoyama, M.; Kimura, H. M.; Inoue, A.
2009-01-01
Alloy optimization in the Ni80-xCrxP16B4 (x = 9-30 at%) alloy system was conducted in order to achieve low Tg, Tx and a large ΔTx. From this study, the Ni65Cr15P16B4 glassy alloy was found to be the optimal alloy. The static and potentiodynamic corrosion behaviours of this alloy were measured. As a result of polarization measurements, it was found that the current density of the non-polished glassy alloy sample was smaller than that of a SUS316L sample. By contrast, the current density of the surface-polished glassy sample was slightly larger than that of the SUS316L sample in the voltage range of 0.3-0.8 V. A bipolar plate was successfully produced by hot-pressing the glassy alloy sheet in a supercooled liquid state. The I-V characteristics of a single cell with the glassy bipolar plates were measured.
50-Ma Initiation of Hawaiian-Emperor Bend Records Major Change in Pacific Plate Motion
NASA Astrophysics Data System (ADS)
Sharp, Warren D.; Clague, David A.
2006-09-01
The Hawaiian-Emperor bend has played a prominent yet controversial role in deciphering past Pacific plate motions and the tempo of plate motion change. New ages for volcanoes of the central and southern Emperor chain define large changes in volcanic migration rate with little associated change in the chain's trend, which suggests that the bend did not form by slowing of the Hawaiian hot spot. Initiation of the bend near Kimmei seamount about 50 million years ago (MA) was coincident with realignment of Pacific spreading centers and early magmatism in western Pacific arcs, consistent with formation of the bend by changed Pacific plate motion.
An analytical investigation of transient effects on rewetting of heated thin flat plates
NASA Technical Reports Server (NTRS)
Platt, J. A.
1993-01-01
The rewetting of a hot surface is a problem of prime importance in the microgravity application of heat pipe technology, where rewetting controls the time before operations can be re-established following depriming of a heat pipe. Rewetting is also important in the nuclear industry (in predicting behavior during loss-of-coolant accidents), as well as in the chemical and petrochemical industries. Recently Chan and Zhang have presented a closed-form solution for the determination of the rewetting speed of a liquid film flowing over a finite (but long) hot plate subject to uniform heating. Unfortunately, their physically unreasonable initial conditions preclude a meaningful analysis of start-up transient behavior. A new nondimensionalization and closed-form solution for an infinitely-long, uniformly-heated plate is presented. Realistic initial conditions (step change in temperature across the wetting front) and boundary conditions (no spatial temperature gradients infinitely far from the wetting front) are employed. The effects of parametric variation on the resulting simpler closed-form solution are presented and compared with the predictions of a 'quasi-steady' model. The time to reach steady-state rewetting is found to be a strong function of the initial dry-region plate temperature. For heated plates it is found that in most cases the effect of the transient response terms cannot be neglected, even for large times.
Creation of Scalable, Cartridge-Based Microreactor Reformers
2010-10-31
empty. In all cases, dense fired cordierite honeycomb- monoliths with a cell density of 72 cells per square inch (CPS1) were supplied from Rauschert...34 nominal pipe thread (NPT) fittings for fluidic connections to the experimental apparatus. All prototype features and fluidic connections were 1/16", with...of 3000 rpm for 1 min. The photoresist is then soft baked at 90°C for 1 minute on a hot plate. The resist is exposed to Mask Al/Cl by proximity
Horizontal baffle for nuclear reactors
Rylatt, John A.
1978-01-01
A horizontal baffle disposed in the annulus defined between the core barrel and the thermal liner of a nuclear reactor thereby physically separating the outlet region of the core from the annular area below the horizontal baffle. The horizontal baffle prevents hot coolant that has passed through the reactor core from thermally damaging apparatus located in the annulus below the horizontal baffle by utilizing the thermally induced bowing of the horizontal baffle to enhance sealing while accommodating lateral motion of the baffle base plate.
Antinociceptive interaction of gabapentin with minocycline in murine diabetic neuropathy.
Miranda, H F; Sierralta, F; Jorquera, V; Poblete, P; Prieto, J C; Noriega, V
2017-02-01
Diabetic neuropathy (DN) is the most common complication of diabetes and pain is one of the main symptoms of diabetic neuropathy, however, currently available drugs are often ineffective and complicated by adverse events. The purpose of this research was to evaluate the antinociceptive interaction between gabapentin and minocycline in a mice experimental model of DN by streptozocin (STZ). The interaction of gabapentin with minocycline was evaluated by the writhing and hot plate tests at 3 and 7 days after STZ injection or vehicle in male CF1 mice. STZ (150 mg/kg, i.p.) produced a marked increase in plasma glucose levels on day 7 (397.46 ± 29.65 mg/dL) than on day 3 (341.12 ± 35.50 mg/dL) and also developed neuropathic pain measured by algesiometric assays. Gabapentin produced similar antinociceptive activity in both writhing and hot plate tests in mice pretreated with STZ. However, minocycline was more potent in the writhing than in the hot plate test in the same type of mice. The combination of gabapentin with minocycline produced synergistic interaction in both test. The combination of gabapentin with minocycline in a 1:1 proportion fulfills all the criteria of multimodal analgesia and this finding suggests that the combination provide a therapeutic alternative that could be used for human neuropathic pain management.
Analgesic effects of glycoproteins from Panax ginseng root in mice.
Wang, Ying; Chen, Yinghong; Xu, Hong; Luo, Haoming; Jiang, Ruizhi
2013-07-30
The root of Panax ginseng C.A. Mey has various beneficial pharmacological effects. The present study aimed to evaluate the analgesic activities of glycoproteins from the root of Panax ginseng C.A. Mey in mice. Glycoproteins were isolated and purified from the root of Panax ginseng C.A. Mey. Physicochemical properties and molecular mass were determined by chemical assay and HPLC. Acetic acid-induced writhing and hot-plate tests were employed to study the analgesic effect of glycoproteins and compared with that of aspirin or morphine. The locomotor activity was tested in mice by using actophometer. Four glycoproteins were obtained. The glycoproteins which protein content was the highest (73.04%) displayed dose-dependent analgesic effect. In writhing test, the glycoproteins significantly inhibited writhes (P<0.001) at the dose of 20 mg/kg by intraperitoneal injection. In hot-plate test, only at the dose of 20 mg/kg prolong the hot-plate latency (P<0.05, at 30 min). In the locomotor activity test, the glycoproteins were significant decrease of motility counts at the dose of 20 and 40 mg/kg. These findings collectively indicate that the glycoproteins from the root of Panax ginseng C.A. Mey exhibited significant analgesic activities and the proteins were the active site, providing evidence for its pharmacal use. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Giorno, Thais Biondino Sardella; Silva, Bárbara Vasconcellos da; Pinto, Angelo da Cunha; Fernandes, Patricia Dias
2016-04-15
There has been growing interest in the synthesis of new derivatives from isatin, found in Isatis genus. Our objectives were to characterize the antinociceptive mechanism of action of isatin, N-methyl-isatin (MI) and N-methyl-3-(2-oxopropyl)-3-hydroxy-2-oxindole (MOI). Substances (0.1-10mg/kg, p.o.) were studied in chemical (paw licking induced by formalin, capsaicin or glutamate) or thermal (hot plate) models of nociception. The involvement of several systems was evaluated using different receptor antagonists. All three substances inhibit both phases of formalin-induced licking, increase the area under the curve and MI and MOI have a higher effect than that of morphine (in hot plate). Capsaicin and glutamate-induced licking were also reduced by all three substances. In the hot plate model, the antinociceptive effect of isatin was reduced by naloxone and atropine; naloxone, atropine and L-NAME reduced MI effect while naloxone, atropine, L-NAME, mecamylamine and ondansetron reduced MOI effect. Our results suggest that isatin, MI and MOI: 1) present activity in models of nociception; 2) capsaicin and glutamate receptors seems to participate in the mechanism of action; 3) opioid, cholinergic, serotoninergic, nitrergic and adrenergic systems may be involved, at least in part, in the mechanism of action of some of these substances. Copyright © 2016 Elsevier Inc. All rights reserved.
Mehta, Ashish K; Bhati, Yogendra; Tripathi, Chakra D; Sharma, Krishna K
2014-08-01
Despite immense advances in the treatment strategies, management of neuropathic pain remains unsatisfactory. Piracetam is a prototype of nootropic drugs, used to improve cognitive impairment. The present study was designed to investigate the effect of piracetam on peripheral neuropathic pain in rats. Neuropathic pain was induced by the chronic constriction injury of the sciatic nerve. Following this, piracetam was intraperitoneally administered for 2 weeks in doses of 50, 100 and 200 mg/kg, and pain was assessed by employing the behavioural tests for thermal hyperalgesia (hot plate and tail flick tests) and cold allodynia (acetone test). After the induction of neuropathic pain, significant development of thermal hyperalgesia and cold allodynia was observed. The administration of piracetam (50 mg/kg) did not have any significant effect on all the behavioural tests. Further, piracetam (100 mg/kg) also had no effect on the hot plate and tail flick tests; however it significantly decreased the paw withdrawal duration in the acetone test. Piracetam in a dose of 200 mg/kg significantly modulated neuropathic pain as observed from the increased hot plate and tail flick latencies, and decreased paw withdrawal duration (in acetone test). Therefore, the present study suggests the potential use of piracetam in the treatment of neuropathic pain, which merits further clinical investigation.
Cancer incidence among population utilizing geothermal hot water: a census-based cohort study.
Kristbjornsdottir, Adalbjorg; Rafnsson, Vilhjalmur
2013-12-15
The aim of the study was to assess whether utilization of geothermal hot-water is associated with risk of cancer. The cohort from census was followed from 1981 to 2010 in nation-wide death and cancer registries. The moving apart of American-Eurasian tectonic plates, observed in Iceland, results in high volcanic activity. The definition of the study populations was based on geological information. The target population was inhabitants of communities located on bedrock younger than 3.3 million years, utilizing hot-water supply generated from geothermal wells since 1972. The two reference populations were inhabitants of communities without this hot-water supply located on areas with less volcanic/geothermal activity, and bedrock older than 3.3 million years. Hazard ratio (HR), and 95% confidence intervals (CI) were adjusted for age, gender, education, housing, reproductive factors and smoking. HR in the geothermal hot-water supply areas for all cancer was 1.15 (95% CI 1.05-1.25) as compared with nongeothermal areas. The HR for breast cancer was 1.40 (1.12-1.75), prostate cancer 1.61 (1.29-2.00), kidney cancer 1.64 (1.11-2.41), lymphatic and haematopoietic tissue cancers 1.45 (1.08-1.95), and for basal cell carcinoma (BCC) of the skin 1.46 (1.16-1.82). Positive exposure-response relations were observed between the risk of these cancers and the degree of volcanic/geothermal activity in the reference areas. Increased incidence of all cancers, breast, prostate, kidney cancer and BCC of the skin was found among the population utilizing geothermal hot-water for decades. More precise information on exposure is needed in future studies. Copyright © 2013 UICC.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lauf, R.J.; Bible, D.W.; Sohns, C.W.
1999-10-19
Systems and methods are described for a wireless instrumented silicon wafer that can measure temperatures at various points and transmit those temperature readings to an external receiver. The device has particular utility in the processing of semiconductor wafers, where it can be used to map thermal uniformity on hot plates, cold plates, spin bowl chucks, etc. without the inconvenience of wires or the inevitable thermal perturbations attendant with them.
Lauf, Robert J.; Bible, Don W.; Sohns, Carl W.
1999-01-01
Systems and methods are described for a wireless instrumented silicon wafer that can measure temperatures at various points and transmit those temperature readings to an external receiver. The device has particular utility in the processing of semiconductor wafers, where it can be used to map thermal uniformity on hot plates, cold plates, spin bowl chucks, etc. without the inconvenience of wires or the inevitable thermal perturbations attendant with them.
Solar heating and hot water system installed at office building, One Solar Place, Dallas, Texas
NASA Technical Reports Server (NTRS)
1980-01-01
A solar heating on cooling system is described which is designed to provide 87 percent of the space heating needs, 100 percent of the potable hot water needs and is sized for future absorption cooling. The collection subsystem consists of 28 solargenics, series 76, flat plate collectors with a total area of 1,596 square feet. The solar loop circulates an ethylene glyco water solution through the collectors into a hot water system exchanger. The water storage subsystem consists of a heat exchanger, two 2,300 gallon concrete hot water storage tanks with built in heat exchangers and a back-up electric boiler. The domestic hot water subsystem sends hot water to the 10,200 square feet floor area office building hot water water fixtures. The building cold water system provides make up to the solar loop, the heating loop, and the hot water concrete storage tanks. The design, construction, cost analysis, operation and maintenance of the solar system are described.
Solar process water heat for the IRIS images custom color photo lab
NASA Technical Reports Server (NTRS)
1980-01-01
The solar facility located at a custom photo laboratory in Mill Valley, California is described. It was designed to provide 59 percent of the hot water requirements for developing photographic film and domestic hot water use. The design load is to provide 6 gallons of hot water per minute for 8 hours per working day at 100 F. It has 640 square feet of flat plate collectors and 360 gallons of hot water storage. The auxillary back up system is a conventional gas-fired water heater. Site and building description, subsystem description, as-built drawings, cost breakdown and analysis, performance analysis, lessons learned, and the operation and maintenance manual are presented.
Drifting--Continents on the Move.
ERIC Educational Resources Information Center
Glenn, William H.
1983-01-01
Plate tectonics is the current framework for understanding earth history and processes. Recent progress in this field is discussed, focusing on continental growth, mountain building, hot spots, and mineral depositions. (JN)
Hot granules medium pressure forming process of AA7075 conical parts
NASA Astrophysics Data System (ADS)
Dong, Guojiang; Zhao, Changcai; Peng, Yaxin; Li, Ying
2015-05-01
High strength aluminum alloy plate has a low elongation at room temperature, which leads to the forming of its components need a high temperature. Liquid or gas is used as the pressure-transfer medium in the existing flexible mould forming process, the heat resistance of the medium and pressurizing device makes the application of aluminum alloy plate thermoforming restricted. To solve this problem, the existing medium is replaced by the heat-resisting solid granules and the general pressure equipments are applied. Based on the pressure-transfer performance test of the solid granules medium, the feasibility that the assumption of the extended Drucker-Prager linear model can be used in the finite element analysis is proved. The constitutive equation, the yield function and the theoretical forming limit diagram(FLD) of AA7075 sheet are established. Through the finite element numerical simulation of hot granules medium pressure forming(HGMF) process, not only the influence laws of the process parameters, such as forming temperature, the blank-holder gap and the diameter of the slab, on sheet metal forming performance are discussed, but also the broken area of the forming process is analyzed and predicted, which are coincided with the technological test. The conical part whose half cone angle is 15° and relative height H/d 0 is 0.57, is formed in one process at 250°C. The HGMF process solves the problems of loading and seal in the existing flexible mould forming process and provides a novel technology for thermoforming of light alloy plate, such as magnesium alloy, aluminium alloy and titanium alloy.
Note: Improving long-term stability of hot-wire anemometer sensors by means of annealing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lundström, H., E-mail: hans.lundstrom@hig.se
2015-08-15
Annealing procedures for hot-wire sensors of platinum and platinum-plated tungsten have been investigated experimentally. It was discovered that the two investigated sensor metals behave quite differently during the annealing process, but for both types annealing may improve long-term stability considerably. Measured drift of sensors both without and with prior annealing is presented. Suggestions for suitable annealing temperatures and times are given.
Hall, A; Short, K; Saltmarsh, M; Fielding, L; Peters, A
2007-09-01
In order to understand the development of the microbial population within a hot-drinks vending machine a new machine was placed in a staff area of a university campus vending only hot chocolate. The machine was cleaned weekly using a detergent based protocol. Samples from the mixing bowl, dispense area, and drink were taken over a 19-wk period and enumerated using plate count agar. Bacillus cereus was identified using biochemical methods. Vended drinks were sampled at 0, 3, 6, and 9 min after vending; the hot chocolate powder was also sampled. Over the 1st 8 wk, a significant increase in the microbial load of the machine components was observed. By the end of the study, levels within the vended drink had also increased significantly. Inactivation of the automatic flush over a subsequent 5-wk period led to a statistically but not operationally significant increase in the microbial load of the dispense area and vended drink. The simple weekly clean had a significant impact on the microbial load of the machine components and the vended drink. This study demonstrated that a weekly, detergent-based cleaning protocol was sufficient to maintain the microbial population of the mixing bowl and dispense point in a quasi-steady state below 3.5 log CFU/cm2 ensuring that the microbial load of the vended drinks was maintained below 3.4 log CFU/mL. The microbial load of the drinks showed no significant changes over 9 min after vending, suggesting only spores are present in the final product.
Infrared Thermography as a Non-destructive Testing Solution for Thermal Spray Metal Coatings
NASA Astrophysics Data System (ADS)
Santangelo, Paolo E.; Allesina, Giulio; Bolelli, Giovanni; Lusvarghi, Luca; Matikainen, Ville; Vuoristo, Petri
2017-12-01
In this work, an infrared (IR) thermographic procedure was evaluated as a non-destructive testing tool to detect damage in thermal spray metallic coatings. As model systems, polished HVOF- and HVAF-sprayed Fe-based layers deposited onto steel plates were employed. Damage by external-object impingement was simulated through a cyclic impact-test apparatus, which induced circumferential and radial cracks across all model systems, and interface cracks of different sizes in distinct samples. Damaged and undamaged plates were bulk-heated to above 100 °C using an IR lamp; their free-convection cooling was then recorded by an IR thermocamera. The intentionally induced defects were hardly detectable in IR thermograms, due to IR reflection and artificial "hot" spots induced by residuals of transfer material from the impacting counterbody. As a micrometer-thin layer of black paint was applied, surface emissivity got homogenized and any artifacts were effectively suppressed, so that failed coating areas clearly showed up as "cold spots." This effect was more apparent when large interface cracks occurred. Finite-element modeling proved the physical significance of the IR-thermography approach, showing that failed coating areas are cooled by surrounding air faster than they are heated by conduction from the hot substrate, which is due to the insulating effect of cracks.
Salicytamide: a New Anti-inflammatory Designed Drug Candidate.
Guedes, Karen Marinho Maciel; Borges, Rosivaldo Santos; Fontes-Júnior, Enéas Andrade; Silva, Andressa Santa Brigida; Fernandes, Luanna Melo Pereira; Cartágenes, Sabrina Carvalho; Pinto, Ana Carla Godinho; Silva, Mallone Lopes; Queiroz, Luana Melo Diogo; Vieira, José Luís Fernandes; Sousa, Pergentino José Cunha; Maia, Cristiane Socorro Ferraz
2018-04-13
Salicytamide is a new drug developed through molecular modelling and rational drug design by the molecular association of paracetamol and salicylic acid. This study was conducted to assess the acute oral toxicity, antinociceptive, and antioedematogenic properties of salicytamide. Acute toxicity was based on the OECD 423 guidelines. Antinociceptive properties were investigated using the writhing, hot plate and formalin tests in Swiss mice. Antioedematogenic properties were evaluated using the carrageenan-induced paw oedema model and croton oil-induced dermatitis in Wistar rats. Salicytamide did not promote behavioural changes or animal deaths during acute oral toxicity evaluation. Furthermore, salicytamide exhibited peripheral antinociceptive activity as evidenced by the reduction in writhing behaviour (ED50 = 4.95 mg/kg) and licking time in the formalin test's inflammatory phase. Also, salicytamide elicited central antinociceptive activity on both hot plate test and formalin test's neurogenic phase. Additionally, salicytamide was effective in reducing carrageenan or croton oil-induced oedema formation. Overall, we have shown that salicytamide, proposed here as a new NSAID candidate, did not induce oral acute toxicity and elicited both peripheral antinociceptive effects (about 10-25 times more potent than its precursors in the writhing test) and antioedematogenic properties. Salicytamide also presented central antinociceptive activity, which seems to be mediated through opioid-independent mechanisms. These findings reveal salicytamide as a promising antinociceptive/antioedematogenic drug candidate.
NASA Astrophysics Data System (ADS)
Jean, B.; Sophie, V. D. G.; Greff-Lefftz, M.; Frizon de Lamotte, D.; Lescanne, M.; Leparmentier, F.
2017-12-01
We compare several models of hot spot reference frames published in the litterature retracing the kinematics of the lithosphere over the mantle for the last 120Ma. We then propose a new model between 130 and 300Ma, based on the comparison of various surface indicators (geological, thermal data from boreholes and compilation of global surface volcanism), a reassessment of hot spots classification and paleomagnetic data. We discuss the implication of our model on the location and timing of several types of surface volcanism (subductions, intracontinental volcanism, rifting and LIPS, kimberlites) that we link to deep structures interpreted from tomographic images. A clear degree two permanent organization of mantle convection during this period of time is obvious, and the subduction rate appears to be episodic. We finally deduce from our model mantle TPW (True Polar Wander), the shifting of the entire mantle relative to the earth's spin axis over the last 300 million years. The inferred global motion of the mantle deduced occurs around a Euler pole which axis is close to the earth equator but varies significantly in longitude with respect to time showing complex tridimensional mass reorganizations in the mantle, probably linked to both LLSVPs and slabs effect.
The mantle flow field beneath western North America.
Silver, P G; Holt, W E
2002-02-08
Although motions at the surface of tectonic plates are well determined, the accompanying horizontal mantle flow is not. We have combined observations of surface deformation and upper mantle seismic anisotropy to estimate this flow field for western North America. We find that the mantle velocity is 5.5 +/- 1.5 centimeters per year due east in a hot spot reference frame, nearly opposite to the direction of North American plate motion (west-southwest). The flow is only weakly coupled to the motion of the surface plate, producing a small drag force. This flow field is probably due to heterogeneity in mantle density associated with the former Farallon oceanic plate beneath North America.
Proton beam shaped by “particle lens” formed by laser-driven hot electrons
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhai, S. H.; Shen, B. F., E-mail: bfshen@mail.shcnc.ac.cn, E-mail: wwpvin@hotmail.com, E-mail: yqgu@caep.cn; Wang, W. P., E-mail: bfshen@mail.shcnc.ac.cn, E-mail: wwpvin@hotmail.com, E-mail: yqgu@caep.cn
2016-05-23
Two-dimensional tailoring of a proton beam is realized by a “particle lens” in our experiment. A large quantity of electrons, generated by an intense femtosecond laser irradiating a polymer target, produces an electric field strong enough to change the trajectory and distribution of energetic protons flying through the electron area. The experiment shows that a strip pattern of the proton beam appears when hot electrons initially converge inside the plastic plate. Then the shape of the proton beam changes to a “fountain-like” pattern when these hot electrons diffuse after propagating a distance.
Three-dimensional simulations of void collapse in energetic materials
NASA Astrophysics Data System (ADS)
Rai, Nirmal Kumar; Udaykumar, H. S.
2018-03-01
The collapse of voids in porous energetic materials leads to hot-spot formation and reaction initiation. This work advances the current knowledge of the dynamics of void collapse and hot-spot formation using 3D reactive void collapse simulations in HMX. Four different void shapes, i.e., sphere, cylinder, plate, and ellipsoid, are studied. For all four shapes, collapse generates complex three-dimensional (3D) baroclinic vortical structures. The hot spots are collocated with regions of intense vorticity. The differences in the vortical structures for the different void shapes are shown to significantly impact the relative sensitivity of the voids. Voids of high surface area generate hot spots of greater intensity; intricate, highly contorted vortical structures lead to hot spots of corresponding tortuosity and therefore enhanced growth rates of reaction fronts. In addition, all 3D voids are shown to be more sensitive than their two-dimensional (2D) counterparts. The results provide physical insights into hot-spot formation and growth and point to the limitations of 2D analyses of hot-spot formation.
NASA Astrophysics Data System (ADS)
Liu, Dongsheng; Li, Qingliang; Emi, Toshihiko
2011-05-01
Key parameters for a thermomechanically controlled processing and accelerated cooling process (TMCP-AcC) were determined for integrated mass production to produce extra high-yield-strength microalloyed low carbon SiMnCrNiCu steel plates for offshore structure and bulk shipbuilding. Confocal scanning microscopy was used to make in-situ observations on the austenite grain growth during reheating. A Gleeble 3800 thermomechanical simulator was employed to investigate the flow stress behavior, static recrystallization (SRX) of austenite, and decomposition behavior of the TMCP conditioned austenite during continuous cooling. The Kocks-Mecking model was employed to describe the constitutive behavior, while the Johnson-Mehl-Avrami-Kolmogorov (JMAK) approach was used to predict the SRX kinetics. The effects of hot rolling schedule and AcC on microstructure and properties were investigated by test-scale rolling trials. The bridging between the laboratory observations and the process parameter determination to optimize the mass production was made by integrated industrial production trials on a set of a 5-m heavy plate mill equipped with an accelerated cooling system. Successful production of 60- and 50-mm-thick plates with yield strength in excess of 460 MPa and excellent toughness at low temperature (213 K (-60 °C)) in the parent metal and the simulated coarse-grained heat affected zone (CGHAZ) provides a useful integrated database for developing advanced high-strength steel plates via TMCP-AcC.
NASA Technical Reports Server (NTRS)
Gonzalez, C. C.; Weaver, R. W.; Ross, R. G., Jr.; Spencer, R.; Arnett, J. C.
1984-01-01
Part of the effort of the Jet Propulsion Laboratory (JPL) Flat-Plate Solar Array Project (FSA) includes a program to improve module and array reliability. A collaborative activity with industry dealing with the problem of hot-spot heating due to the shadowing of photovoltaic cells in modules and arrays containing several paralleled cell strings is described. The use of multiparallel strings in large central-station arrays introduces the likelihood of unequal current sharing and increased heating levels. Test results that relate power dissipated, current imbalance, cross-strapping frequency, and shadow configuration to hot-spot heating levels are presented. Recommendations for circuit design configurations appropriate to central-station applications that reduce the risk of hot-spot problems are offered. Guidelines are provided for developing hot-spot tests for arrays when current imbalance is a threat.
Shuttle APS propellant thermal conditioner study
NASA Technical Reports Server (NTRS)
Fulton, D. L.
1971-01-01
The conditioner design concept selected for evaluation consists of an integral reactor and baffle-type heat exchanger. Heat exchange is accomplished by flowing reactor hot gases past a series of slotted and formed plates, through which the conditioned propellant flows. Heat transfer analysis has resulted in the selection of a reactor hot gas nominal mixture ratio of 1.0, giving a combustion temperature of 1560 F with a hydrogen inlet temperature of 275 R. Worst case conditions result in a combustion gas temperature of 2060 F, satisfying the condition of no damage to the conditioner in case of failure to flow cold fluid. In addition, evaluation of hot gas flow requirements and conditioner weight has resulted in the selection of a reactor hot gas exhaust temperature of 750 R.
Integral gas seal for fuel cell gas distribution assemblies and method of fabrication
Dettling, Charles J.; Terry, Peter L.
1985-03-19
A porous gas distribution plate assembly for a fuel cell, such as a bipolar assembly, includes an inner impervious region wherein the bipolar assembly has good surface porosity but no through-plane porosity and wherein electrical conductivity through the impervious region is maintained. A hot-pressing process for forming the bipolar assembly includes placing a layer of thermoplastic sealant material between a pair of porous, electrically conductive plates, applying pressure to the assembly at elevated temperature, and allowing the assembly to cool before removing the pressure whereby the layer of sealant material is melted and diffused into the porous plates to form an impervious bond along a common interface between the plates holding the porous plates together. The distribution of sealant within the pores along the surface of the plates provides an effective barrier at their common interface against through-plane transmission of gas.
Method of fabricating an integral gas seal for fuel cell gas distribution assemblies
Dettling, Charles J.; Terry, Peter L.
1988-03-22
A porous gas distribution plate assembly for a fuel cell, such as a bipolar assembly, includes an inner impervious region wherein the bipolar assembly has good surface porosity but no through-plane porosity and wherein electrical conductivity through the impervious region is maintained. A hot-pressing process for forming the bipolar assembly includes placing a layer of thermoplastic sealant material between a pair of porous, electrically conductive plates, applying pressure to the assembly at elevated temperature, and allowing the assembly to cool before removing the pressure whereby the layer of sealant material is melted and diffused into the porous plates to form an impervious bond along a common interface between the plates holding the porous plates together. The distribution of sealant within the pores along the surface of the plates provides an effective barrier at their common interface against through-plane transmission of gas.
System for phase-contrast x-ray radiography using X pinch radiation and a method thereof
Chandler, Katherine; Chelkovenko, Tatiana; Hammer, David; Pikuz, Sergei; Sinars, Daniel; Song, Byungmoo
2007-11-06
A radiograph system with an anode plate, a cathode plate, and a power source coupled to said anode plate and the cathode plate. At least two wires coupled between the anode plate and the cathode plate provide a configuration to form an X-pinch having a photon source size of less than five microns at energies above 2.5 keV. Material at the configuration forming the X-pinch vaporizes upon application of a suitable current to the wires forming a dense hot plasma and emitting a single x-ray pulse with sufficient photons having energies in the range of from about 2.5 keV to about 20 keV to provide a phase contrast image of an object in the path of the photons. Multiple simultaneous images may be formed of a plurality of objects. Suitable filters and x-ray detectors are provided.
Comparative performance of twenty-three types of flat plate solar energy collectors
NASA Technical Reports Server (NTRS)
Simon, F. F.
1975-01-01
Report compares efficiencies of 23 solar collectors for four different purposes: operating a Rankine-cycle engine, heating or absorption air conditioning, heating hot water, and heating a swimming pool.
Mollashahi, Mahtab; Abbasnejad, Mehdi; Esmaeili-Mahani, Saeed
2018-08-05
The phytohormone abscisic acid exists in animal tissues particularly in the brain. However, its neurophysiological effects have not yet been fully clarified. This study was designed to evaluate the possible antinociceptive effects of abscisic acid on animal models of pain and determine its possible signaling mechanism. Tail-flick, hot-plate and formalin tests were used to assess the nociceptive threshold. All experiments were carried out on male Wistar rats. To determine the role of Peroxisome proliferator-activated receptor β/δ (PPARβ/δ) and opioid receptors on the induction of abscisic acid antinociception, specific antagonists were injected 15 min before abscisic acid. The data showed that abscisic acid (5, 10 and 15 µg/rat, i.c.v.) significantly decreased pain responses in formalin test. In addition, it could also produce dose-dependent antinociceptive effect in tail-flick and hot-plate tests. Administration of PPARβ/δ antagonist (GSK0660, 80 nM, i.c.v.) significantly attenuated the antinociceptive effect of abscisic acid in all tests. The antinociceptive effects of abscisic acid were completely inhibited by naloxone (6 µg, i.c.v.) during the time course of tail-flick and hot-plate tests. The results indicated that the central injection of abscisic acid has potent pain-relieving property which is mediated partly via the PPAR β/δ and opioid signaling. Copyright © 2018 Elsevier B.V. All rights reserved.
Zarr, Robert R
2010-01-01
An assessment of uncertainties for the National Institute of Standards and Technology (NIST) 1016 mm Guarded-Hot-Plate apparatus is presented. The uncertainties are reported in a format consistent with current NIST policy on the expression of measurement uncertainty. The report describes a procedure for determination of component uncertainties for thermal conductivity and thermal resistance for the apparatus under operation in either the double-sided or single-sided mode of operation. An extensive example for computation of uncertainties for the single-sided mode of operation is provided for a low-density fibrous-glass blanket thermal insulation. For this material, the relative expanded uncertainty for thermal resistance increases from 1 % for a thickness of 25.4 mm to 3 % for a thickness of 228.6 mm. Although these uncertainties have been developed for a particular insulation material, the procedure and, to a lesser extent, the results are applicable to other insulation materials measured at a mean temperature close to 297 K (23.9 °C, 75 °F). The analysis identifies dominant components of uncertainty and, thus, potential areas for future improvement in the measurement process. For the NIST 1016 mm Guarded-Hot-Plate apparatus, considerable improvement, especially at higher values of thermal resistance, may be realized by developing better control strategies for guarding that include better measurement techniques for the guard gap thermopile voltage and the temperature sensors.
Zarr, Robert R.
2010-01-01
An assessment of uncertainties for the National Institute of Standards and Technology (NIST) 1016 mm Guarded-Hot-Plate apparatus is presented. The uncertainties are reported in a format consistent with current NIST policy on the expression of measurement uncertainty. The report describes a procedure for determination of component uncertainties for thermal conductivity and thermal resistance for the apparatus under operation in either the double-sided or single-sided mode of operation. An extensive example for computation of uncertainties for the single-sided mode of operation is provided for a low-density fibrous-glass blanket thermal insulation. For this material, the relative expanded uncertainty for thermal resistance increases from 1 % for a thickness of 25.4 mm to 3 % for a thickness of 228.6 mm. Although these uncertainties have been developed for a particular insulation material, the procedure and, to a lesser extent, the results are applicable to other insulation materials measured at a mean temperature close to 297 K (23.9 °C, 75 °F). The analysis identifies dominant components of uncertainty and, thus, potential areas for future improvement in the measurement process. For the NIST 1016 mm Guarded-Hot-Plate apparatus, considerable improvement, especially at higher values of thermal resistance, may be realized by developing better control strategies for guarding that include better measurement techniques for the guard gap thermopile voltage and the temperature sensors. PMID:27134779
Kambur, Oleg; Männistö, Pekka T; Viljakka, Kaarin; Reenilä, Ilkka; Lemberg, Kim; Kontinen, Vesa K; Karayiorgou, Maria; Gogos, Joseph A; Kalso, Eija
2008-10-01
Catechol-O-methyltransferase (COMT) polymorphisms modulate pain and opioid analgesia in human beings. It is not clear how the effects of COMT are mediated and only few relevant animal studies have been performed. Here, we used old male Comt gene knock-out mice as an animal model to study the effects of COMT deficiency on nociception that was assessed by the hot plate and tail flick tests. Stress-induced analgesia was achieved by forced swim. Morphine antinociception was measured after 10 mg/kg of morphine subcutaneously. Morphine tolerance was produced with subcutaneous morphine pellets and withdrawal provoked with subcutaneous naloxone. In the hot plate test, morphine-induced antinociception was significantly greater in the COMT knock-out mice, compared to the wild-type mice. This may be due to increased availability of opioid receptors as suggested by previous human studies. In the tail flick test, opioid-mediated stress-induced analgesia was absent and morphine-induced analgesia was decreased in COMT knock-out mice. In the hot plate test, stress-induced analgesia developed to all mice regardless of the COMT genotype. There were no differences between the genotypes in the baseline nociceptive thresholds, morphine tolerance and withdrawal. Our findings show, for the first time, the importance of COMT activity in stress- and morphine-induced analgesia in mice. COMT activity seems to take part in the modulation of nociception not only in the brain, as suggested earlier, but also at the spinal/peripheral level.
Loyd, S J; Becker, T W; Conrad, C P; Lithgow-Bertelloni, C; Corsetti, F A
2007-09-04
The thermal evolution of Earth is governed by the rate of secular cooling and the amount of radiogenic heating. If mantle heat sources are known, surface heat flow at different times may be used to deduce the efficiency of convective cooling and ultimately the temporal character of plate tectonics. We estimate global heat flow from 65 Ma to the present using seafloor age reconstructions and a modified half-space cooling model, and we find that heat flow has decreased by approximately 0.15% every million years during the Cenozoic. By examining geometric trends in plate reconstructions since 120 Ma, we show that the reduction in heat flow is due to a decrease in the area of ridge-proximal oceanic crust. Even accounting for uncertainties in plate reconstructions, the rate of heat flow decrease is an order of magnitude faster than estimates based on smooth, parameterized cooling models. This implies that heat flow experiences short-term fluctuations associated with plate tectonic cyclicity. Continental separation does not appear to directly control convective wavelengths, but rather indirectly affects how oceanic plate systems adjust to accommodate global heat transport. Given that today's heat flow may be unusually low, secular cooling rates estimated from present-day values will tend to underestimate the average cooling rate. Thus, a mechanism that causes less efficient tectonic heat transport at higher temperatures may be required to prevent an unreasonably hot mantle in the recent past.
NASA Astrophysics Data System (ADS)
Ege, Kerem; Roozen, N. B.; Leclère, Quentin; Rinaldi, Renaud G.
2018-07-01
In the context of aeronautics, automotive and construction applications, the design of light multilayer plates with optimized vibroacoustical damping and isolation performances remains a major industrial challenge and a hot topic of research. This paper focuses on the vibrational behavior of three-layered sandwich composite plates in a broad-band frequency range. Several aspects are studied through measurement techniques and analytical modelling of a steel/polymer/steel plate sandwich system. A contactless measurement of the velocity field of plates using a scanning laser vibrometer is performed, from which the equivalent single layer complex rigidity (apparent bending stiffness and apparent damping) in the mid/high frequency ranges is estimated. The results are combined with low/mid frequency estimations obtained with a high-resolution modal analysis method so that the frequency dependent equivalent Young's modulus and equivalent loss factor of the composite plate are identified for the whole [40 Hz-20 kHz] frequency band. The results are in very good agreement with an equivalent single layer analytical modelling based on wave propagation analysis (model of Guyader). The comparison with this model allows identifying the frequency dependent complex modulus of the polymer core layer through inverse resolution. Dynamical mechanical analysis measurements are also performed on the polymer layer alone and compared with the values obtained through the inverse method. Again, a good agreement between these two estimations over the broad-band frequency range demonstrates the validity of the approach.
Loyd, S. J.; Becker, T. W.; Conrad, C. P.; Lithgow-Bertelloni, C.; Corsetti, F. A.
2007-01-01
The thermal evolution of Earth is governed by the rate of secular cooling and the amount of radiogenic heating. If mantle heat sources are known, surface heat flow at different times may be used to deduce the efficiency of convective cooling and ultimately the temporal character of plate tectonics. We estimate global heat flow from 65 Ma to the present using seafloor age reconstructions and a modified half-space cooling model, and we find that heat flow has decreased by ∼0.15% every million years during the Cenozoic. By examining geometric trends in plate reconstructions since 120 Ma, we show that the reduction in heat flow is due to a decrease in the area of ridge-proximal oceanic crust. Even accounting for uncertainties in plate reconstructions, the rate of heat flow decrease is an order of magnitude faster than estimates based on smooth, parameterized cooling models. This implies that heat flow experiences short-term fluctuations associated with plate tectonic cyclicity. Continental separation does not appear to directly control convective wavelengths, but rather indirectly affects how oceanic plate systems adjust to accommodate global heat transport. Given that today's heat flow may be unusually low, secular cooling rates estimated from present-day values will tend to underestimate the average cooling rate. Thus, a mechanism that causes less efficient tectonic heat transport at higher temperatures may be required to prevent an unreasonably hot mantle in the recent past. PMID:17720806
NASA Technical Reports Server (NTRS)
Bhandari, Pradeep; Anderson, Kevin
2013-01-01
The challenging range of landing sites for which the Mars Science Laboratory Rover was designed, requires a rover thermal management system that is capable of keeping temperatures controlled across a wide variety of environmental conditions. On the Martian surface where temperatures can be as cold as -123 C and as warm as 38 C, the rover relies upon a Mechanically Pumped Fluid Loop (MPFL) Rover Heat Rejection System (RHRS) and external radiators to maintain the temperature of sensitive electronics and science instruments within a -40 C to 50 C range. The RHRS harnesses some of the waste heat generated from the rover power source, known as the Multi Mission Radioisotope Thermoelectric Generator (MMRTG), for use as survival heat for the rover during cold conditions. The MMRTG produces 110 W of electrical power while generating waste heat equivalent to approximately 2000 W. Heat exchanger plates (hot plates) positioned close to the MMRTG pick up this survival heat from it by radiative heat transfer. Winds on Mars can be as fast as 15 m/s for extended periods. They can lead to significant heat loss from the MMRTG and the hot plates due to convective heat pick up from these surfaces. Estimation of this convective heat loss cannot be accurately and adequately achieved by simple textbook based calculations because of the very complicated flow fields around these surfaces, which are a function of wind direction and speed. Accurate calculations necessitated the employment of sophisticated Computational Fluid Dynamics (CFD) computer codes. This paper describes the methodology and results of these CFD calculations. Additionally, these results are compared to simple textbook based calculations that served as benchmarks and sanity checks for them. And finally, the overall RHRS system performance predictions will be shared to show how these results affected the overall rover thermal performance.
DOE Office of Scientific and Technical Information (OSTI.GOV)
J. A. Smith; D. L. Cottle; B. H. Rabin
2013-09-01
This report summarizes work conducted to-date on the implementation of new laser-based capabilities for characterization of bond strength in nuclear fuel plates, and presents preliminary results obtained from fresh fuel studies on as-fabricated monolithic fuel consisting of uranium-10 wt.% molybdenum alloys clad in 6061 aluminum by hot isostatic pressing. Characterization involves application of two complementary experimental methods, laser-shock testing and laser-ultrasonic imaging, collectively referred to as the Laser Shockwave Technique (LST), that allows the integrity, physical properties and interfacial bond strength in fuel plates to be evaluated. Example characterization results are provided, including measurement of layer thicknesses, elastic properties ofmore » the constituents, and the location and nature of generated debonds (including kissing bonds). LST provides spatially localized, non-contacting measurements with minimum specimen preparation, and is ideally suited for applications involving radioactive materials, including irradiated materials. The theoretical principles and experimental approaches employed in characterizing nuclear fuel plates are described, and preliminary bond strength measurement results are discussed, with emphasis on demonstrating the capabilities and limitations of these methods. These preliminary results demonstrate the ability to distinguish bond strength variations between different fuel plates. Although additional development work is necessary to validate and qualify the test methods, these results suggest LST is viable as a method to meet fuel qualification requirements to demonstrate acceptable bonding integrity.« less
Using Google Earth to Explore Multiple Data Sets and Plate Tectonic Concepts
NASA Astrophysics Data System (ADS)
Goodell, L. P.
2015-12-01
Google Earth (GE) offers an engaging and dynamic environment for exploration of earth science data. While GIS software offers higher-level analytical capability, it comes with a steep learning curve and complex interface that is not easy for the novice, and in many cases the instructor, to negotiate. In contrast, the intuitive interface of GE makes it easy for students to quickly become proficient in manipulating the globe and independently exploring relationships between multiple data sets at a wide range of scales. Inquiry-based, data-rich exercises have been developed for both introductory and upper-level activities including: exploration of plate boundary characteristics and relative motion across plate boundaries; determination and comparison of short-term and long-term average plate velocities; crustal strain analysis (modeled after the UNAVCO activity); and determining earthquake epicenters, body-wave magnitudes, and focal plane solutions. Used successfully in undergraduate course settings, for TA training and for professional development programs for middle and high school teachers, the exercises use the following GE data sets (with sources) that have been collected/compiled by the author and are freely available for non-commercial use: 1) tectonic plate boundaries and plate names (Bird, 2003 model); 2) real-time earthquakes (USGS); 3) 30 years of M>=5.0 earthquakes, plotted by depth (USGS); 4) seafloor age (Mueller et al., 1997, 2008); 5) location and age data for hot spot tracks (published literature); 6) Holocene volcanoes (Smithsonian Global Volcanism Program); 7) GPS station locations with links to times series (JPL, NASA, UNAVCO); 8) short-term motion vectors derived from GPS times series; 9) long-term average motion vectors derived from plate motion models (UNAVCO plate motion calculator); 10) earthquake data sets consisting of seismic station locations and links to relevant seismograms (Rapid Earthquake Viewer, USC/IRIS/DELESE).
Structure and Mechanical Properties of Friction Stir Weld Joints of Magnesium Alloy AZ31
NASA Astrophysics Data System (ADS)
Nagasawa, T.; Otsuka, M.; Yokota, T.; Ueki, T.
The applicability of friction stir welding to hot rolled sheet of commercial magnesium alloy AZ31 plates has been investigated. Friction stir weld joint showed mechanical strength comparable to that of base material, though the ductility remained at one half of that of the latter. The results are consistent with the microstructure which is characterized by a fine grained bond layer bounded by-intermediate grained base metals. It is found that both anodizing treatment and insertion of aluminum foil between batting faces do not degrade the joint properties at all. The results suggest that friction stir welding can be potentially applied to magnesium alloy.
Insights Into the Causes of Arc Rifting From 2-D Dynamic Models of Subduction
NASA Astrophysics Data System (ADS)
Billen, Magali I.
2017-11-01
Back-arc spreading centers initiate as fore-arc or arc rifting events when extensional forces localize within lithosphere weakened by hydrous fluids or melting. Two models have been proposed for triggering fore-arc/arc rifting: rollback of the subducting plate causing trench retreat or motion of the overriding plate away from the subduction zone. This paper demonstrates that there is a third mechanism caused by an in situ instability that occurs when the thin high-viscosity boundary, which separates the weak fore arc from the hot buoyant mantle wedge, is removed. Buoyant upwelling mantle causes arc rifting, drives the overriding plate away from the subducting plate, and there is sufficient heating of the subducting plate crust and overriding plate lithosphere to form adakite or boninite volcanism. For spontaneous fore-arc/arc rifting to occur a broad region of weak material must be present and one of the plates must be free to respond to the upwelling forces.
Sen, Sudip Kumar; Raut, Sangeeta; Satpathy, Soumya; Rout, Prangya Ranjan; Bandyopadhyay, Bidyut; Das Mohapatra, Pradeep Kumar
2014-01-01
Background: Amylases play a vital role in biotechnological studies and rank an important position in the world enzyme market (25% to 33%). Bioprocess method of amylase production is more effective than the other sources, since the technique is easy, cost effective, fast, and the enzymes of required properties can be procured. Objectives: The current study aimed to report the characteristics of novel amylase producing bacterial strains isolated from Taptapani hot spring, Odisha, India. Materials and Methods: Bacterial strains were isolated by dilution plating method from the water samples collected from Taptapani Hot Spring, Odisha and screened for amylase production through starch hydrolysis. The bacterial isolates were identified morphologically, biochemically, and finally by 16S rDNA profiling. Results: Based on the morphological, physiological, biochemical characteristics and the molecular characterization, the isolates SS1, SS2, and SS3 were identified as Bacillus barbaricus, Aeromonas veroni, and Stenotrophomonas maltophilia, respectively. The approximate molecular weight of enzymes from SS1, SS2, and SS3 strains were 19 kDa, 56 kDa and 49 kDa, respectively. Conclusions: The current report isolates, characterizes, and demonstrates the novel heat-adapted amylase-producing bacteria SS1, SS2 and SS3 from Taptapani hot spring, indicating its potentiality and stability under acidic conditions. PMID:25741425
... fatty meats like ribs, bacon, and hot dogs. Choose cakes, cookies, candies, and ice cream as just occasional treats. help strengthen bones. Be sure your morning coffee ... half your plate fruits and vegetables Add fruit to meals as ...
Code of Federal Regulations, 2011 CFR
2011-07-01
... material and a moving part of the machine, burned by hot surfaces or exposed to electric shock. Examples of... the employer to do a specific task in that area. Dockboards (car and bridge plates) mean devices for...
Solar-energy-system performance evaluation, October 1980-August 1981
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wetzel, P.E.
The solar site is an Animal Quarantine Center in Upton, New York, using 2484 ft/sup 2/ of flat-plate collectors and 5300 gallons of solar hot water storage located outside and above ground. The system was designed to provide 20% of the annual heating load and 100% of the annual domestic hot water load. The solar system actually provided 5% of the total system load. Many control and mechanical malfunctions contributed to the poor performance. (MHR)
System Design Package for SIMS Prototype System 3, Solar Heating and Domestic Hot Water
NASA Technical Reports Server (NTRS)
1978-01-01
A collation of documents and drawings are presented that describe a prototype solar heating and hot water system using liquid flat plate collectors and a gas or electric furnace energy subsystem. The system was designed for installation into a single-family dwelling. The description, performance specification, subsystem drawings, verification plan/procedure, and hazard analysis of the system are packaged for evaluation of the system with information sufficient to assemble a similar system.
NASA Astrophysics Data System (ADS)
Ghigo, M.; Basso, S.; Bavdaz, M.; Conconi, P.; Citterio, O.; Civitani, M.; Friedrich, P.; Gallieni, D.; Guldimann, B.; Martelli, F.; Negri, R.; Pagano, G.; Pareschi, G.; Parodi, G.; Proserpio, L.; Salmaso, B.; Scaglione, F.; Spiga, D.; Tagliaferri, G.; Terzi, L.; Tintori, M.; Vongehr, M.; Wille, E.; Winter, A.; Zambra, A.
2010-07-01
The mirrors of the International X-ray Observatory (IXO) consist of a large number of high quality segments delivering a spatial resolution better than 5 arcsec. A study concerning the slumping of thin glass foils for the IXO mirrors is under development in Europe, funded by ESA and led by the Brera Observatory. We are investigating two approaches, the "Direct" and "Indirect" slumping technologies, being respectively based on the use of convex and concave moulds. In the first case during the thermal cycle the optical surface of the glass is in direct contact with the mould surface, while in the second case it is the rear side of the foil which touches the master. Both approaches present pros and cons and aim of this study is also to make an assessment of both processes and to perform a trade-off between the two. The thin plates are made of D263glass produced by Schott. Each plate is 0.4 mm thick, with a reflecting area of 200 mm x 200 mm; the mould are made of Fused Silica. After the thermal cycle the slumped MPs are characterized to define their optical quality and microroughness. The adopted integration process foresees the bonding of the slumped foils to a rigid backplane by means of reinforcing ribs. During the bonding process the plates are constrained to stay in close contact to the surface of the master (i.e. the same mould used for the hot slumping process) by the application of a vacuum pump suction. In this way spring-back deformations and low frequency errors still present on the foil profile after slumping can be corrected. In this paper we present the preliminary results concerning achieved during the first part of the project.
Calculation methods study on hot spot stress of new girder structure detail
NASA Astrophysics Data System (ADS)
Liao, Ping; Zhao, Renda; Jia, Yi; Wei, Xing
2017-10-01
To study modeling calculation methods of new girder structure detail's hot spot stress, based on surface extrapolation method among hot spot stress method, a few finite element analysis models of this welded detail were established by finite element software ANSYS. The influence of element type, mesh density, different local modeling methods of the weld toe and extrapolation methods was analyzed on hot spot stress calculation results at the toe of welds. The results show that the difference of the normal stress in the thickness direction and the surface direction among different models is larger when the distance from the weld toe is smaller. When the distance from the toe is greater than 0.5t, the normal stress of solid models, shell models with welds and non-weld shell models tends to be consistent along the surface direction. Therefore, it is recommended that the extrapolated point should be selected outside the 0.5t for new girder welded detail. According to the results of the calculation and analysis, shell models have good grid stability, and extrapolated hot spot stress of solid models is smaller than that of shell models. So it is suggested that formula 2 and solid45 should be carried out during the hot spot stress extrapolation calculation of this welded detail. For each finite element model under different shell modeling methods, the results calculated by formula 2 are smaller than those of the other two methods, and the results of shell models with welds are the largest. Under the same local mesh density, the extrapolated hot spot stress decreases gradually with the increase of the number of layers in the thickness direction of the main plate, and the variation range is within 7.5%.
Presheath and Double Layer Structures in an Argon Helicon Plasma Source
NASA Astrophysics Data System (ADS)
Siddiqui, M. Umair
Ion velocities and temperatures, plasma density, potential, and electron temperatures are measured in a 13.56 MHz helicon produced argon plasma upstream from a grounded plate inside a 10 cm ID cylindrical Pyrex vacuum chamber. The plate is held at psi = 0° → 60° relative to the background axial magnetic field in the system. For the psi = 0° experiment, two distinct helicon discharge equilibria are observed at 500 W rf power, 900 G magnetic field, and a neutral pressure of 3 → 4 mTorr. Both modes exhibit a localized region of hot electrons (Th ≈ 10 eV, Tc ≈ 3.5 eV). For the first mode the hot electrons are confined by a localized potential structure and the density decreases monotonically towards the grounded plate. For the second mode the hot electrons cool off gradually in space due to heat conduction generating a downstream density peak and no major potential structures are observed. It is found that the type of discharge mode is determined by the location of the grounded plate, the length of the presheath, and the rf electron heating mechanism. For the psi = 16° → 60° plate positions, ion flow to the boundary where a 1 kG magnetic field is obliquely incident is measured at 1, 3, and 6.5 mTorr neutral pressure and 450 → 750 W rf power. The results are compared to the magnetic presheath models put forth by Chodura [Phys. Fluids 25, 1628 (1982)], Riemann [Phys. Plasmas 1, 552 (1994)], and Ahedo [Phys. Plasmas 4, 4419 (1997)]. The 1 mTorr dataset is used to benchmark a one-dimensional fluid model for the ion flow in the presheath. Definitions of the "magnetic presheath" are discussed. The fluid model in conjuction with the data show that the ion velocities in the E x B direction can be 10% → 40% percent of the sound speed for the angles investigated. Ion flow to fusion experiment boundaries and Hall thruster walls is discussed.
Thermally-Driven Mantle Plumes Reconcile Hot-spot Observations
NASA Astrophysics Data System (ADS)
Davies, D.; Davies, J.
2008-12-01
Hot-spots are anomalous regions of magmatism that cannot be directly associated with plate tectonic processes (e.g. Morgan, 1972). They are widely regarded as the surface expression of upwelling mantle plumes. Hot-spots exhibit variable life-spans, magmatic productivity and fixity (e.g. Ito and van Keken, 2007). This suggests that a wide-range of upwelling structures coexist within Earth's mantle, a view supported by geochemical and seismic evidence, but, thus far, not reproduced by numerical models. Here, results from a new, global, 3-D spherical, mantle convection model are presented, which better reconcile hot-spot observations, the key modification from previous models being increased convective vigor. Model upwellings show broad-ranging dynamics; some drift slowly, while others are more mobile, displaying variable life-spans, intensities and migration velocities. Such behavior is consistent with hot-spot observations, indicating that the mantle must be simulated at the correct vigor and in the appropriate geometry to reproduce Earth-like dynamics. Thermally-driven mantle plumes can explain the principal features of hot-spot volcanism on Earth.
Biological shielding test of hot cells with high active source 60Co (300 TBq)
NASA Astrophysics Data System (ADS)
Švrčula, P.; Zoul, D.; Zimina, M.; Petříčková, A.; Adamíková, T.; Schulc, M.; Srba, O.
2017-11-01
This article describes a method for testing of the efficiency of the biological shielding of the hot cell facility, which were constructed as a part of the project SUSEN. Ten hot cells and one semi-hot cell are present in the facility Radiochemistry II. The shielding is made from steel plates. In order to demonstrate sufficient efficiency of the biological shielding of the hot cells and a correspondence between measured and contractual values at selected points. The test was done using sealed high activity 60Co sources. The results are also used as a proof of the optimization of radiation protection for the workplace of this type. The results confirm significant optimization of radiation protection at the workplace. The dose received by a staff do not exceed one tens of annual limit during active service. Obtained results fulfill general requirements of radiation protection and will be used for further active service of hot cells facility.
NASA Astrophysics Data System (ADS)
Khaerudini, Deni S.; Berliana, Rina; Prakoso, Gatra B.; Insiyanda, Dita R.; Alva, Sagir
2018-03-01
This work concerns the utilization of mill scale, a by-product of iron and steel formed during the hot rolling of steel, as a potential material for use as bipolar plates in proton exchange membrane fuel cells (PEMFCs). On the other hand, mill scale is considered a very rich in iron source having characteristic required such as for current collector in bipolar plate and would significantly contribute to lower the overall cost of PEMFC based fuel cell systems. In this study, the iron reach source of mill scale powder, after sieving of 150 mesh, was mechanically alloyed with the aluminium source containing 30 wt.% using a shaker mill for 3 h. The mixed powders were then pressed at 300 MPa and sintered at various temperatures of 400, 450 and 500 °C for 1 h under inert gas atmosphere. The structural changes of powder particles during mechanical alloying and after sintering were studied by x-ray diffractometry, scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX), microhardness measurement, and density - porosity analysis. The details of the performance variation of three different sintering conditions can be preliminary explained by the metallographic and crystallographic structure and phase analysis as well as sufficient mechanical strength of the sintered materials was presented in this report.
NASA Technical Reports Server (NTRS)
1979-01-01
The solar system, installed in a new building, was designed to provide 52 percent of the estimated annual space heating load and 84 percent of the estimated annual potable hot water requirement. The liquid flat plate collectors are ground-mounted and cover a total area of 5125 square feet. The system will provide supplemental heat for the school's closed-loop water-to-air heat pump system and domestic hot water. The storage medium is water inside steel tanks with a capacity of 11,828 gallons for space heating and 1,600 gallons for domestic hot water. The solar heating facility is described and drawings are presented of the completed system which was declared operational in September 1978, and has functioned successfully since.
NASA Astrophysics Data System (ADS)
Iaffaldano, Giampiero; DeMets, Charles
2017-04-01
Reconstructions of absolute plate motions underpin our understanding of the plate torque balance, but are challenging due to difficulties in inferring well-dated rates and directions of plate movements from hot spot tracks. Useful information about plate dynamics can be inferred from rapid absolute plate motion changes, as these are linked only to the torque(s) that changed. Here we infer late Neogene changes in the absolute motions of North America and possibly Antarctica from changes in the easier-to-determine relative plate motions recorded along the Arctic, northern Mid-Atlantic and Southwest Indian Ridges. We show that Eurasia/North America and Nubia/North America motions changed by the same amount between 8 and 5 Ma, as may have Nubia/Antarctica and Somalia/Antarctica plate motions. By considering additional, independent constraints on Somalia/India plate motion, we argue that a scenario in which North America and Antarctica absolute motions changed is the simplest one that explains the observed changes in relative motions. We speculate that these changes are linked to the late Neogene dynamics of the Pacific plate.
NASA Astrophysics Data System (ADS)
Iaffaldano, G.; DeMets, C.
2016-08-01
Reconstructions of absolute plate motions underpin our understanding of the plate torque balance, but are challenging due to difficulties in inferring well-dated rates and directions of plate movements from hot spot tracks. Useful information about plate dynamics can be inferred from rapid absolute plate motion changes, as these are linked only to the torque(s) that changed. Here we infer late Neogene changes in the absolute motions of North America and possibly Antarctica from changes in the easier-to-determine relative plate motions recorded along the Arctic, northern Mid-Atlantic and Southwest Indian Ridges. We show that Eurasia/North America and Nubia/North America motions changed by the same amount between 8 and 5 Ma, as may have Nubia/Antarctica and Somalia/Antarctica plate motions. By considering additional, independent constraints on Somalia/India plate motion, we argue that a scenario in which North America and Antarctica absolute motions changed is the simplest one that explains the observed changes in relative motions. We speculate that these changes are linked to the late Neogene dynamics of the Pacific plate.
NASA Astrophysics Data System (ADS)
Hložek, M.; Trojek, T.
2017-08-01
Archaeological surveys and metal detector prospecting yield a great amount of coins from the medieval period. Naturally, some of these are counterfeit which an experienced numismatist can determine without using chemical methods. The production of counterfeit coins in the middle ages took place in castles, caves or other remote areas where waste from this activity can still be found today - copper sheets, technical ceramics and counterfeit coins. Until recently, it has been assumed that medieval counterfeit coins are made by silver-plating copper blanks using an amalgam. However, the performed analyses reveal that there are many more techniques of counterfeiting of coins. Other techniques were based on e.g. tin amalgam plating of the blanks or alloying so-called white metal with silver-like appearance from which the coins were minted. Current chemical analyses indicate that the coins were often tinned by hot dipping with no amalgamation. Micro-X-ray fluorescence analysis has been chosen as a suitable non-destructive method to identify present chemical elements in investigated artifacts and to quantify their concentrations. In addition, a quick technique telltale the plating was applied. This technique utilizes the detected fluorescence ratio Kα/Kβ of copper, which is the main ingredient of a lot of historical metallic materials.
The Earth and Planetary Sciences.
ERIC Educational Resources Information Center
Wetherill, George W.; Drake, Charles L.
1980-01-01
The last two decades of collecting evidence to support the plate tectonic theory is reviewed. Discussion also involves how other terrestrial plants show evidence of once having been hot but with long-term stability and no continuing convection. (Author/SA)
Microstructural and Mechanical Properties of Hot Roll Bonded Titanium Alloy/Low Carbon Steel Plate
NASA Astrophysics Data System (ADS)
Yu, Chao; Qi, Zi-chen; Yu, Hui; Xu, Cheng; Xiao, Hong
2018-03-01
In this paper, a titanium alloy and low carbon steel were bonded via hot rolling in a vacuum, and the effect of roll bonding temperature and reduction ratio on the microstructural and mechanical properties of the plate was studied. When the bonding temperature was between 850 and 1050 °C, the shear strength of the interface increased with an increasing reduction ratio from 18 to 70%. At a bonding temperature of 950 °C and at a rolling reduction ratio of 70%, the best bonding strength was obtained, and a shear fracture occurred on the low carbon steel matrix. At 1050 °C, brittle compounds, i.e., TiC, FeTi, and Fe2Ti, formed at the interface, which decreased the bonding strength. The large reduction ratio can break up compounds at the interface and extrude fresh metal for bonding, thereby increasing the bonding strength.
Choi, Eun-Mi; Hwang, Jae-Kwan
2003-11-01
The anti-inflammatory activities of Piper cubeba (fruit), Physalis angulata (flower) and Rosa hybrida (flower) were determined by carrageenan-induced paw edema, arachidonic acid-induced ear edema and formaldehyde-induced arthritis in mice. The anti-allergic and analgesic activities of these plants were also studied by using 2,4-dinitrofluorobenzene (DNFB)-induced contact hypersensitivity reaction (type IV) and hot plate test in mice, respectively. These plant extracts clearly exhibited inhibitory effects against acute and subacute inflammation by oral administration (200 mg/kg). Also, administration (200 mg/kg, p.o.) of plant extracts for 1 week significantly inhibited type IV allergic reaction in mice (P<0.05). Rosa hybrida showed an analgesic effect against hot plate-induced thermal stimulation at a dose of 200 mg/kg. These results provide support for the use of Rosa hybrida in relieving inflammatory pain, and insight into the development of new agents for treating inflammatory diseases.
REMS Wind Sensor Preliminary Results
NASA Astrophysics Data System (ADS)
De La Torre Juarez, M.; Gomez-Elvira, J.; Navarro, S.; Marin, M.; Torres, J.; Rafkin, S. C.; Newman, C. E.; Pla-García, J.
2015-12-01
The REMS instrument is part of the Mars Science Laboratory payload. It is a sensor suite distributed over several parts of the rover. The wind sensor, which is composed of two booms equipped with a set of hot plate anemometers, is installed on the Rover Sensing Mast (RSM). During landing most of the hot plates of one boom were damaged, most likely by the pebbles lifted by the Sky Crane thruster. The loss of one wind boom necessitated a full review of the data processing strategy. Different algorithms have been tested on the readings of the first Mars year, and these results are now archived in the Planetary Data System (PDS), The presentation will include a description of the data processing methods and of the resulting products, including the typical evolution of wind speed and direction session-by-session, hour-by-hour and other kinds of statistics . A review of the wind readings over the first Mars year will also be presented.
Nozzle cooling of hot surfaces with various orientations
NASA Astrophysics Data System (ADS)
Ondrouskova, Jana; Luks, Tomas; Horsky, Jaroslav
2012-04-01
The aim of this research is an investigation of hot surface orientation influence on heat transfer during cooling by a nozzle. Two types of nozzles were used for the experiments (air-mist nozzle and hydraulic nozzle). A test plate was cooled in three positions - top, side and bottom position. The aim was to simulate a cooling situation in the secondary zone of a continuous casting machine. Temperature was measured in seven locations under the cooled surface by thermocouples. These data were used for an inverse heat conduction problem and then boundary conditions were computed. These boundary conditions are represented by surface temperature, heat transfer coefficient and heat flux. Results from an inverse calculation were compared in each position of thermocouples separately. The total cooling intensity was specified for all configurations of nozzles and test plate orientation. Results are summarised in a graphical and numerical format.
Purves, Murray; Parkes, David
2016-05-01
Three atmospheric dispersion models--DIFFAL, HPAC, and HotSpot--of differing complexities have been validated against the witness plate deposition dataset taken during the Full-Scale Radiological Dispersal Device (FSRDD) Field Trials. The small-scale nature of these trials in comparison to many other historical radiological dispersion trials provides a unique opportunity to evaluate the near-field performance of the models considered. This paper performs validation of these models using two graphical methods of comparison: deposition contour plots and hotline profile graphs. All of the models tested are assessed to perform well, especially considering that previous model developments and validations have been focused on larger-scale scenarios. Of the models, HPAC generally produced the most accurate results, especially at locations within ∼100 m of GZ. Features present within the observed data, such as hot spots, were not well modeled by any of the codes considered. Additionally, it was found that an increase in the complexity of the meteorological data input to the models did not necessarily lead to an improvement in model accuracy; this is potentially due to the small-scale nature of the trials.
Electric field makes Leidenfrost droplets take a leap.
Wildeman, Sander; Sun, Chao
2016-12-06
Leidenfrost droplets, i.e. droplets whose mobility is ensured by a thin vapor film between the droplet and a hot plate, are exposed to an external electric field. We find that in a strong vertical electric field the droplet can start to bounce progressively higher, defying gravitational attraction. From the droplet's trajectory we infer the temporal evolution of the amount of charge on the droplet. This reveals that the charge starts high and then decreases in steps as the droplet slowly evaporates. After each discharge event the charge is in a fixed proportion to the droplet's surface area. We show that this behavior can be accurately modeled by treating the droplet as a conducting sphere that occasionally makes electrical contact with the hot plate, at intervals dictated by an electro-capillary instability in the vapor film. An analysis of the kinetic and potential energies of the bouncing droplet reveals that, while the overall motion is damped, the droplet occasionally experiences a sudden boost, keeping its energy close to the value for which the free fall trajectory and droplet oscillation are in sync. This helps the droplet to escape from the hot surface when finally the electrical surface forces overtake gravity.
NASA Astrophysics Data System (ADS)
Gordon, Richard G.; Cox, Allan; O'Hare, Scott
1984-10-01
The apparent polar wander path for a plate is determined from paleomagnetic data by plotting a time sequence of paleomagnetic poles, each representing the location of the earth's spin axis as seen from the plate. Apparent polar wander paths consist of long, gently curved segments termed tracks linked by short segments with sharp curvature termed cusps. The tracks correspond to time intervals when the direction of plate motion was constant, and the cusps correspond to time intervals when the direction of plate motion was changing. Apparent polar wander tracks, like hot spot tracks, tend to lie along small circles. The center of a circle is called a hot spot Euler pole in the case of hot spot tracks and a paleomagnetic Euler pole in the case of paleomagnetic apparent polar wander paths. Both types of tracks mark the motion of a plate with respect to a point, a rising mantle plume in the case of hot spot tracks and the earth's paleomagnetic axis in the case of apparent polar wander paths. Unlike approaches uced in previous studies, paleomagnetic Euler pole analysis yields all three components of motion—including the east-west motion—of a plate with respect to the paleomagnetic axis. A new method for analyzing paleomagnetic poles along a track by using a maximum likelihood criterion gives the best fit paleomagnetic Euler pole and an ellipsoid of 95% confidence about the paleomagnetic Euler pole. In analyzing synthetic and real data, we found that the ellipsoids are elongate, the long axes being aligned with a great circle drawn from the paleomagnetic Euler pole to the center of the apparent polar wander track. This elongation is caused by the azimuths of circular tracks being better defined than their radii of curvature. A Jurassic-Cretaceous paleomagnetic Euler pole for North America was determined from 13 paleomagnetic poles. This track begins with the Wingate and Kayenta formations (about 200 Ma) and ends with the Niobrara Formation (about 87 Ma). Morgan's hot spot Euler pole for 200-90 Ma lies only 15° outside the 95% confidence ellipsoid of the paleomagnetic Euler pole. The good but not perfect agreement reflects displacement between the hot spot and paleomagnetic reference frames at an average rate that is smaller by an order of magnitude than the rate at which the faster plates are moving. The angular velocity of North America about the Jurassic-Cretaceous paleomagnetic Euler pole was determined by plotting the angular positions of paleomagnetic poles along the track as a function of age. For the Cretaceous the angular velocity was too small to measure. During the Jurassic the angular velocity was high, corresponding to a root-mean-square velocity of 70 km/m.y. for the North American plate. A short time interval of even more rapid movement during the Middle and Late Jurassic, possibly corresponding to the beginning of rapid displacement between North America and Africa, is suggested by the data. The direction of absolute motion of North America during the Jurassic was toward the northwest. A Carboniferous-Permian-Triassic paleomagnetic Euler pole was determined from 26 paleomagnetic poles. The progression of poles along this track is consistent with known ages and stratigraphy, except for some systematic differences between poles from Triassic rocks on the Colorado Plateau and poles from Triassic rocks off the Colorado Plateau. These differences could be due to a small clockwise rotation of the Colorado Plateau with respect to cratonal North America, or to miscorrelations between Triassic rocks on the Colorado Plateau and off the Colorado Plateau, or to large lag times between the deposition and magnetization of some rock units, or to some combination of these possibilities. Despite these ambiguities in interpreting paleomagnetic data from Triassic rocks, the general pattern of apparent polar wander and plate motion during the Carboniferous through Triassic is clear: The root-mean-square velocity of North America was slow (about 20 km/m.y.) during the Carboniferous, probably slow (about 20 km/m.y.) during the Permian, but rapid (60-100 km/m.y.) during the Triassic. Paleomagnetic Euler pole analysis establishes that the present slow (less than 30 km/m.y.) velocity of large continental plates like North America is not an intrinsic property of the plates. Occasionally these plates have, for intervals of 50 ± 20 m.y., moved as rapidly as the oceanic plates are moving today. In our interpretation, during times of rapid motion the continents were attached along a passive margin to oceanic lithosphere that was being subducted at some distance from the continent. Rapid motion stopped when the oceanic lithosphere had been consumed by subduction. If North America, Greenland, and Eurasia were joined as a single land mass during the Jurassic, then a likely location for the subducting oceanic plate attached to this landmass is along the southern margin of the cratonal core of Asia with the oceanic plate extending into Tethys. At the cusp between the Carboniferous-Permian-Triassic track and the Jurassic-Cretaceous track, the trend of the path changes by 160°. The western point of the cusp, which is delineated by paleomagnetic poles from the Chinle, Wingate, and Kayenta formations, is 13° farther west in our analysis than it is in commonly accepted apparent polar wander paths for North America. An implication for terrane analysis is that northward displacements found by using our Late Triassic and Early Jurassic poles are up to 2000 km smaller than are those found by using previously published Late Triassic and Early Jurassic cratonal poles.
NASA Astrophysics Data System (ADS)
Sibrant, A.; Davaille, A.; Marques, F. O.; Hildenbrand, A.
2014-12-01
Born 200 Ma ago, the central Atlantic presents nowadays a large low seismic velocity anomaly in the lower mantle, a cluster of "hot" spots (Azores, Cape Verde, Madeira, Canary, Great Meteor), a mid-ocean ridge, and a triple junction located in the Azores. We carried out laboratory experiments to examine the possible links between mantle instabilities, plate boundary migration, and the development of the volcanism on various spatial and temporal scales. Coupled with the current knowledge of these volcanic areas (tomography, tectonics and K/Ar dating), our fluid mechanics experiments suggest that: (1) The Azores, as Canary, Cape Verde, Madeira Islands and Great Meteor seamounts might be the surface expression of a cluster of mantle instabilities rising from the top of a large thermochemical dome located in the lower mantle. However, such secondary plumes present a strong time-dependence 5-40 Myr time scale. (2) These secondary instabilities could be sufficiently weak to adapt their motions to the pre-existing force balance, and morphology and mechanical properties of the lithosphere. Based on current knowledge and modelling, we present a scenario of the Central Atlantic area evolution in the last 100 Ma combining a triple junction and decompression melting-generated buoyant material (i.e. such in volatiles and/or temperature) under a cooling and thickening lithosphere.
Wang, Xia; Zhang, Luyan; Chen, Gang
2011-11-01
As a self-regulating heating device, positive temperature coefficient ceramic heater was employed for hot embossing and thermal bonding of poly(methyl methacrylate) microfluidic chip because it supplied constant-temperature heating without electrical control circuits. To emboss a channel plate, a piece of poly(methyl methacrylate) plate was sandwiched between a template and a microscopic glass slide on a positive temperature coefficient ceramic heater. All the assembled components were pressed between two elastic press heads of a spring-driven press while a voltage was applied to the heater for 10 min. Subsequently, the embossed poly(methyl methacrylate) plate bearing negative relief of channel networks was bonded with a piece of poly(methyl methacrylate) cover sheet to obtain a complete microchip using a positive temperature coefficient ceramic heater and a spring-driven press. High quality microfluidic chips fabricated by using the novel embossing/bonding device were successfully applied in the electrophoretic separation of three cations. Positive temperature coefficient ceramic heater indicates great promise for the low-cost production of poly(methyl methacrylate) microchips and should find wide applications in the fabrication of other thermoplastic polymer microfluidic devices.
Splash flow from a metal plate hit by an electron beam pulse
DOE Office of Scientific and Technical Information (OSTI.GOV)
Garcia, M., LLNL
1997-09-01
When a pulsed electron beam hits a metal plate with sufficient energy a volume of the metal becomes hot fluid that subsequently sprays out of the plate. A second pulse of electrons traveling toward the plate would scatter and degrade before impacting the solid plate because of its encounter with the diffuse material of the initial splash. People designing electron beam machines for use as pulsed radiation sources wish to eliminate the interaction between the electrons and the splash because they want sharp radiation pulses emitted from the solid plate. This report presents a compressible fluid model of this splashmore » flow and compares specific cases with experiments and comprehensive calculations performed by B. DeVolder and others at the Los Alamos National Laboratory, see reference (1). My aim was to develop as simple a theory as possible to calculate the speed and density of the splash flow. I have used both simplifying assumptions and mathematical approximations to develop convenient formulas. As I wished to make a clear and interesting presentation of this work to a diverse audience that includes people outside the specialty of fluid dynamics, some of my descriptions may seem wordier than necessary. The plan of the report is as follows. In the section called ``energy deposition`` I describe how an electron beam deposits energy in a solid plate, converting some of the material into a hot fluid. The initial temperature of this fluid is the key parameter in determining the nature of the subsequent flow; an explicit formula is shown. Flow occurs in two regions: along a streamtube within the metal plate and as an expanding plume outside the metal plate. Flow within the plate is described in the section called ``isentropic flow.`` This flow occurs as expansion waves move at the speed of sound through the streamtube. The analysis of this flow provides a formula for the mass flow over time from the plate into the external splash. The section called ``centered expansion`` elaborates on the nature of certain approximations I have made in treating the wave phenomena in both the streamtube and splash flows. The section called ``splash flow`` presents a formula to describe the material density as a function of space and time outside the plate. This formula depends on the time- dependent material density at the plate, which was found during the streamtube analysis. The section called ``examples`` shows the results of specific calculations and a comparison to computational and experimental results described in reference (1). The final section, ``possible future work,`` poses new questions.« less
Laser-generated magnetic fields in quasi-hohlraum geometries
NASA Astrophysics Data System (ADS)
Pollock, Bradley; Turnbull, David; Ross, Steven; Hazi, Andrew; Ralph, Joseph; Lepape, Sebastian; Froula, Dustin; Haberberger, Dan; Moody, John
2014-10-01
Laser-generated magnetic fields of 10--40 T have been produced with 100--4000 J laser drives at Omega EP and Titan. The fields are generated using the technique described by Daido et al. [Phys. Rev. Lett. 56, 846 (1986)], which works by directing a laser through a hole in one plate to strike a second plate. Hot electrons generated in the laser-produced plasma on the second plate collect on the first plate. A strap connects the two plates allowing a current of 10 s of kA to flow and generate a solenoidal magnetic field. The magnetic field is characterized using Faraday rotation, b-dot probes, and proton radiography. Further experiments to study the effect of the magnetic field on hohlraum performance are currently scheduled for Omega. This work was performed under the auspices of the United States Department of Energy by the Lawrence Livermore National Laboratory under Contract No. DE-AC52-07NA-27344.
NASA Astrophysics Data System (ADS)
Ruderich, R.; Fernholz, H. H.
1986-02-01
Attention is given to the turbulent and disturbed flow over a bluff plate having a long splitter plate in its plane-of-symmetry, so that the flow separates at the sharp bevelled edge of the bluff plate, forms a free shear layer above the reverse flow region, and reattaches on the splitter plate over a narrow region that is curved in spanwise direction. Hot wire and pulsed wire anemometry were used to measure mean velocity, Reynolds shear stress and Reynolds normal stress distributions, and spectra and integral length-scales were measured to investigate the state and structure of the flow. Mean and fluctuating qualities showed a self-similar behavior in a short region upstream of the reattachment, as well as 'profile-similarity' in the separated shear layer and along the splitter plate downstream from reattachment. No flapping or reattaching shear layer was observed.
Dulu, Thomas D; Kanui, Titus I; Towett, Philemon K; Maloiy, Geoffrey M; Abelson, Klas S P
2014-01-01
The naked mole-rat (Heterocephalus glaber) is a promising animal model for the study of pain mechanisms, therefore a thorough characterization of this species is essential. The aim of the present study was to establish the naked mole-rat as a model for studying the cholinergic receptor system in antinociception by investigating the involvement of muscarinic, nicotinic and opioid receptors in nociceptive tests in this species. The effects of systemic administration of the muscarinic receptor agonist oxotremorine and the nicotinic receptor agonist epibatidine were investigated in the tail-flick, the hot-plate, and the formalin tests. The effects of co-administration of the muscarinic receptor antagonist atropine, the nicotinic receptor antagonist mecamylamine, and the opioid receptor antagonist naloxone were also investigated. Oxotremorine and epibatidine induced a significant, dose-dependent antinociceptive effect in the tail-flick, hot-plate, and formalin tests, respectively. The effects of oxotremorine and epibatidine were blocked by atropine and mecamylamine, respectively. In all three nociceptive tests, naloxone in combination with oxotremorine or epibatidine enhanced the antinociceptive effects of the drugs. The present study demonstrated that stimulation of muscarinic and nicotinic receptors produces antinociceptive effects in the naked-mole rat. The reversal effect of atropine and mecamylamine suggests that this effect is mediated by cholinergic receptors. As naloxone increases the antinociceptive effects of cholinergic agonists, it is suggested that the cholinergic antinociception acts via a gateway facilitated by opioid receptor blockage; however, the precise interaction between these receptor systems needs further investigation.
Support pedestals for interconnecting a cover and nozzle band wall in a gas turbine nozzle segment
Yu, Yufeng Phillip; Itzel, Gary Michael; Webbon, Waylon Willard; Bagepalli, Radhakrishna; Burdgick, Steven Sebastian; Kellock, Iain Robertson
2002-01-01
A gas turbine nozzle segment has outer and inner band portions. Each band portion includes a nozzle wall, a cover and an impingement plate between the cover and nozzle wall defining two cavities on opposite sides of the impingement plate. Cooling steam is supplied to one cavity for flow through the apertures of the impingement plate to cool the nozzle wall. Structural pedestals interconnect the cover and nozzle wall and pass through holes in the impingement plate to reduce localized stress otherwise resulting from a difference in pressure within the chamber of the nozzle segment and the hot gas path and the fixed turbine casing surrounding the nozzle stage. The pedestals may be cast or welded to the cover and nozzle wall.
NASA Astrophysics Data System (ADS)
Malinowski, Z.; Telejko, T.; Cebo-Rudnicka, A.; Szajding, A.; Rywotycki, M.; Hadała, B.
2016-09-01
The industrial rolling mills are equipped with systems for controlled water cooling of hot steel products. A cooling rate affects the final mechanical properties of steel which are strongly dependent on microstructure evolution processes. In case of water jets cooling the heat transfer boundary condition can be defined by the heat transfer coefficient. In the present study one and three dimensional heat conduction models have been employed in the inverse solution to heat transfer coefficient. The inconel plate has been heated to about 900oC and then cooled by one, two and six water jets. The plate temperature has been measured by 30 thermocouples. The heat transfer coefficient distributions at plate surface have been determined in time of cooling.
78 FR 9676 - Clad Steel Plate From Japan: Continuation of Antidumping Duty Order
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-11
... hot-rolling of the cladding metal to ensure efficient welding to the basic metal; any other method of... welding (e.g., electrocladding), in which the cladding metal (nickel, chromium, etc.) is applied to the...
Regional Geological Maps of the Northeast Pacific - Standard Navy Ocean Area NP-9
1978-01-01
creates the next Washington, and British Columbia. All the land area, except island in the chain. Thus, many island chains, for example. the that seaward of...the San Andreas Fault of California, is part of Hawaiian Islands , seem to indicate the path of the plate over the North American Plate. such "hot...turbiditc deposition from the nearby been deposited by bottom currents, volcanic sources such as the Hawaiian Islands and from the deposition of sediments
Shock initiation of explosives: Temperature spikes and growth spurts
NASA Astrophysics Data System (ADS)
Bassett, Will P.; Dlott, Dana D.
2016-08-01
When energetic materials are subjected to high-velocity impacts, the first steps in the shock-to-detonation transition are the creation, ignition, and growth of hot spots. We used 1-3.2 km s-1 laser-launched flyer plates to impact powdered octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine, a powerful explosive, and monitored hundreds of emission bursts with an apparatus that determined temperature and emissivity at all times. The time-dependent volume fraction of hot spots was determined by measuring the time-dependent emissivity. After the shock, most hot spots extinguished, but the survivors smoldered for hundreds of nanoseconds until their temperatures spiked, causing a hot spot growth spurt. Depending on the impact duration, the growth spurts could be as fast as 300 ns and as slow as 13 μs.
20 kHz, 25 kVA node power transformer
NASA Technical Reports Server (NTRS)
Hussey, S.
1989-01-01
The electrical and mechanical design information and the electrical and thermal testing performed on the 440-208-V rms, 20-kHz, 25-kVa prototype node transformer are summarized. The calculated efficiency of the node transformer is 99.3 percent based on core loss and copper loss test data, and its maximum calculated load regulation is 0.7 percent. The node transformer has a weight of 19.7 lb and has a power density of 0.8 lb/kW. The hot-spot temperature rise is estimated to be 33 C above the cold plate mounting base. This proof-of-concept transformer design is a viable candidate for the space station Freedom application.
21 CFR 177.1010 - Acrylic and modified acrylic plastics, semirigid and rigid.
Code of Federal Regulations, 2013 CFR
2013-04-01
...) Selection of extractability conditions. These are to be chosen as provided in § 176.170(c) of this chapter..., weighed platinum dish, evaporated to 2-5 milliliters on a nonsparking, low-temperature hot plate and dried...
21 CFR 177.1010 - Acrylic and modified acrylic plastics, semirigid and rigid.
Code of Federal Regulations, 2011 CFR
2011-04-01
...) Selection of extractability conditions. These are to be chosen as provided in § 176.170(c) of this chapter..., weighed platinum dish, evaporated to 2-5 milliliters on a nonsparking, low-temperature hot plate and dried...
21 CFR 177.1010 - Acrylic and modified acrylic plastics, semirigid and rigid.
Code of Federal Regulations, 2012 CFR
2012-04-01
...) Selection of extractability conditions. These are to be chosen as provided in § 176.170(c) of this chapter..., weighed platinum dish, evaporated to 2-5 milliliters on a nonsparking, low-temperature hot plate and dried...
Wilson study cycles: Research relative to ocean geodynamic cycles
NASA Technical Reports Server (NTRS)
Kidd, W. S. F.
1985-01-01
The effects of conversion of Atlantic (rifted) margins to convergent plate boundaries; oceanic plateaus at subduction zones; continental collision and tectonic escape; southern Africa rifts; and global hot spot distribution on long term development of the continental lithosphere were studied.
Code of Federal Regulations, 2011 CFR
2011-07-01
... beading, straightening, corrugating, flanging, or bending rolls; and hot or cold rolling mills. (ii) All... area between the dies; power presses; and plate punches. (iii) All bending machines, such as apron...
Solar energy system performance evaluation: Seasonal report for fern, Tunkhannock, Pennsylvania
NASA Technical Reports Server (NTRS)
1980-01-01
The operational and thermal performance of a variety of solar systems installed in operational test sites are described. The analysis is based on instrumented system data monitored and collected for at least one full season of operation. The long-term field performance of the installed system is reported, and technical contributions to the definition of techniques and requirements for solar energy system design are made. The solar energy system was designed to supply space heating and domestic hot water for single-family residences. The system consists of air flat plate collectors, storage tank, pumps, heat exchangers, associated plumbing, and controls.
Solar energy system performance evaluation: Seasonal report for SEMCO, Loxahatchee, Florida
NASA Technical Reports Server (NTRS)
1980-01-01
The operational and thermal performance of a variety of solar systems installed in operational test sites are described. The analysis used is based on instrumented system data monitored and collected for at least one full season of operation. The long-term field performance of the installed system and the technical contributions to the definition of techniques and requirements solar energy system design are analyzed. The solar energy system was designed to supply domestic hot water for a family of four, single-family residences. It consists of two liquid flat plate collectors, single tank, controls, and transport lines.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Labrousse, M.; Lerouge, B.; Dupuy, G.
1978-04-01
THERMOS is a water reactor designed to provide hot water up to 120/sup 0/C for district heating or for desalination applications. It is a 100-MW reactor based on proven technology: oxide fuel plate elements, integrated primary circuit, and reactor vessel located in the bottom of a pool. As in swimming pool reactors, the pool is used for biological shielding, emergency core cooling, and fission product filtering (in case of an accident). Before economics, safety is the main characteristic of the concept: no fuel failure admitted, core under water in any accidental configuration, inspection of every ''nuclear'' component, and double-wall containment.
NASA Astrophysics Data System (ADS)
Hanamuro, T.; Umeda, K.; Maeda, K.
2008-12-01
Although there is no known evidence of volcanism during the Pliocene nor the Quaternary in the Kii Peninsula, it has long been recognized to host several hot springs with discharge temperatures greater than 60°C. In addition, numerous small-scale vein-type metal deposits are distributed around the southern part of the peninsula, with a heat source thought to be the Middle Miocene acidic magmatism associated with Kumano Acidic Rocks. The results of the TL (Thermoluminescence), FT (Fission Track) and K-Ar dating of altered rocks from these hot spring areas showed that the vein-type ore deposits and their surrounding altered rocks experienced high temperature hydrothermal alteration related to acidic magmatism in the Middle Miocene, whereas relatively low temperature alteration has occurred since the Pliocene in the Hongu and Totsukawa hot spring areas [Hanamuro et al., 2008]. Chemical and isotope data were obtained for fluid inclusions trapped in hydrothermal minerals in the peripheral parts of the high-temperature hot springs and in vein-type ore deposits. The hot spring inclusions indicate temperatures reached ~100°C with salinities of about 2 wt % (NaCl equiv.). In contrast, the inclusions in the vein-type deposits are characterized by high temperature fluids (>260°C) with high salinity (>5 wt %). The 3He/4He ratios of the hot spring inclusions have relatively high values, generally in agreement with those of the present-day hydrothermal fluids, indicating a significant contribution by deep source gases (i.e., mantle helium). These results suggest that the amagmatic hydrothermal system related to high-temperature hot springs in the southern Kii Peninsula have formed since the Pliocene and were caused by high temperature fluids with a lower crust provenance, presumably supplied from the subducting slab of the Philippine Sea Plate (PHS) [Umeda et al., 2006]. After a hiatus of about 4 Ma, the PHS resumed subduction beneath the SW Japan Arc at around 6 Ma [Kamata and Kodama, 1994]. This indicates that the present-day plate system for the SW Japan arc formed at around 6 Ma and continues to the present day. Although we lack definitive information on the age of hydrothermal alteration, it seems reasonable to infer that the amagmatic hydrothermal activity since about 6 Ma in the southern Kii Peninsula has occurred in a manner synchronous with the present-day plate system of the SW Japan Arc. Reference Hanamuro et al. (2008): Japanese Magazine of Mineralogical and Petrological Sciences, 37, 27-38 (in Japanese with English Abstract). Kamata and Kodama (1994): Journal of Geophysical Research, 233, 69-81. Umeda et al. (2006): Journal of Volcanology and Geothermal Research, 149, 47-61.
Advanced Vacuum Plasma Spray (VPS) for a Robust, Longlife and Safe Space Shuttle Main Engine (SSME)
NASA Technical Reports Server (NTRS)
Holmes, Richard R.; Elam, Sandra K.; McKechnie, Timothy N.; Power, Christopher A.
2010-01-01
In 1984, the Vacuum Plasma Spray Lab was built at NASA/Marshall Space Flight Center for applying durable, protective coatings to turbine blades for the space shuttle main engine (SSME) high pressure fuel turbopump. Existing turbine blades were cracking and breaking off after five hot fire tests while VPS coated turbine blades showed no wear or cracking after 40 hot fire tests. Following that, a major manufacturing problem of copper coatings peeling off the SSME Titanium Main Fuel Valve Housing was corrected with a tenacious VPS copper coating. A patented VPS process utilizing Functional Gradient Material (FGM) application was developed to build ceramic lined metallic cartridges for space furnace experiments, safely containing gallium arsenide at 1260 degrees centigrade. The VPS/FGM process was then translated to build robust, long life, liquid rocket combustion chambers for the space shuttle main engine. A 5K (5,000 Lb. thrust) thruster with the VPS/FGM protective coating experienced 220 hot firing tests in pristine condition with no wear compared to the SSME which showed blanching (surface pulverization) and cooling channel cracks in less than 30 of the same hot firing tests. After 35 of the hot firing tests, the injector face plates disintegrated. The VPS/FGM process was then applied to spraying protective thermal barrier coatings on the face plates which showed 50% cooler operating temperature, with no wear after 50 hot fire tests. Cooling channels were closed out in two weeks, compared to one year for the SSME. Working up the TRL (Technology Readiness Level) to establish the VPS/FGM process as viable technology, a 40K thruster was built and is currently being tested. Proposed is to build a J-2X size liquid rocket engine as the final step in establishing the VPS/FGM process TRL for space flight.
A rapid detection method using flow cytometry to monitor the risk of Legionella in bath water.
Taguri, Toshitsugu; Oda, Yasunori; Sugiyama, Kanji; Nishikawa, Toru; Endo, Takuro; Izumiyama, Shinji; Yamazaki, Masayuki; Kura, Fumiaki
2011-07-01
Legionella species are the causative agents of human legionellosis, and bathing facilities have been identified as the sources of infection in several outbreaks in Japan. Researchers in Japan have recently reported evidence of significant associations between bacterial counts and the occurrence of Legionella in bathing facilities and in a hot tub model. A convenient and quantitative bacterial enumeration method is therefore required as an indicator of Legionella contamination or disinfection to replace existing methods such as time-consuming Legionella culture and expensive Legionella-DNA amplification. In this study, we developed a rapid detection method (RDM) to monitor the risk of Legionella using an automated microbial analyzing device based on flow cytometry techniques to measure the total number of bacteria in water samples within two minutes, by detecting typical patterns of scattered light and fluorescence. We first compared the results of our RDM with plate counting results for five filtered hot spring water samples spiked with three species of bacteria, including Legionella. Inactivation of these samples by chlorine was also assessed by the RDM, a live/dead bacterial fluorescence assay and plate counting. Using the RDM, the lower limit of quantitative bacterial counts in the spiked samples was determined as 3.0×10(3)(3.48log)counts mL(-1). We then used a laboratory model of a hot tub and found that the RDM could monitor the growth curve of naturally occurring heterotrophic bacteria with 1 and 2 days' delayed growth of amoeba and Legionella, respectively, and could also determine the killing curve of these bacteria by chlorination. Finally, samples with ≥3.48 or <3.48log total bacterial counts mL(-1) were tested using the RDM from 149 different hot tubs, and were found to be significantly associated with the positive or negative detection of Legionella with 95% sensitivity and 84% specificity. These findings indicated that the RDM can be used for Legionella control at bathing facilities, especially those where the effectiveness of chlorine is reduced by the presence of Fe(2+), Mn(2+), NH(4)(+), skin debris, and/or biofilms in the water. Copyright © 2011 Elsevier B.V. All rights reserved.
Antinociception induced by rosuvastatin in murine neuropathic pain.
Miranda, Hugo F; Sierralta, Fernando; Aranda, Nicolas; Poblete, Paula; Castillo, Rodrigo L; Noriega, Viviana; Prieto, Juan Carlos
2018-06-01
Neuropathic pain, and subsequent hypernociception, can be induced in mice by paclitaxel (PTX) administration and partial sciatic nerve ligation (PSNL). Its pharmacotherapy has been a clinical challenge, due to a lack of effective treatment. In two models of mouse neuropathic pain (PTX and PSNL) the antinociception induced by rosuvastatin and the participation of proinflammatory biomarkers, interleukin (IL)- 1β, TBARS and glutathione were evaluated. A dose-response curve for rosuvastatin ip was obtained on cold plate, hot plate and Von Frey assays. Changes on spinal cord levels of IL-1β, glutathione and lipid peroxidation were measured at 7 and 14days in PTX and PSNL murine models. PTX or PSNL were able to induce in mice peripheral neuropathy with hypernociception, either to 7 and 14days. Rosuvastatin induced a dose dependent antinociception in hot plate, cold plate and Von Frey assays. The increased levels of IL-1β or TBARS induced by pretreatment with PTX or PSNL were reduced by rosuvastatin. The reduction of spinal cord glutathione, by PTX or PSNL, expressed as the ratio GSH/GSSG, were increased significantly in animals pretreated with rosuvastatin. The anti-inflammatory properties of statins could underlie their beneficial effects on neuropathic pain by reduction of proinflammatory biomarkers and activation of glia. The findings of this study suggest a potential usefulness of rosuvastatin in the treatment of neuropathic pain. Copyright © 2018 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier B.V. All rights reserved.
Geodynamic Modeling of the Subduction Zone around the Japanese Islands
NASA Astrophysics Data System (ADS)
Honda, S.
2017-06-01
In this review, which focuses on our research, we describe the development of the thermomechanical modeling of subduction zones, paying special attention to those around the Japanese Islands. Without a sufficient amount of data and observations, models tended to be conceptual and general. However, the increasing power of computational tools has resulted in simple analytical and numerical models becoming more realistic, by incorporating the mantle flow around the subducting slab. The accumulation of observations and data has made it possible to construct regional models to understand the detail of the subduction processes. Recent advancements in the study of the seismic tomography and geology around the Japanese Islands has enabled new aspects of modeling the mantle processes. A good correlation between the seismic velocity anomalies and the finger-like distribution of volcanoes in northeast Japan has been recognized and small-scale convection (SSC) in the mantle wedge has been proposed to explain such a feature. The spatial and temporal evolution of the distribution of past volcanoes may reflect the characteristics of the flow in the mantle wedge, and points to the possibility of the flip-flopping of the finger-like pattern of the volcano distribution and the migration of volcanic activity from the back-arc side to the trench side. These observations are found to be qualitatively consistent with the results of the SSC model. We have also investigated the expected seismic anisotropy in the presence of SSC. The fast direction of the P-wave anisotropy generally shows the trench-normal direction with a reduced magnitude compared to the case without SSC. An analysis of full 3D seismic anisotropy is necessary to confirm the existence and nature of SSC. The 3D mantle flow around the subduction zone of plate-size scale has been modeled. It was found that the trench-parallel flow in the sub-slab mantle around the northern edge of the Pacific plate at the junction between the Aleutian arc and the Kurile arc is generally weak and we have suggested the possible contribution of a hot anomaly in the sub-slab mantle as the origin of possible trench-parallel flow there. A 3D mantle flow model of the back-arc around the junction between the northeast Japan arc and the Kurile arc shows a trench-normal flow at a shallow depth. As a result, the expected seismic anisotropy shows the fast direction normal to the arc, even in the region of oblique subduction. This result is generally consistent with observations there. The existence of a hot anomaly in the sub-slab mantle under the Pacific plate was proposed from an analysis of the seismic tomography, and we have studied its possible origins. The origin of a hot anomaly adjacent to the cold downgoing flow, typically observed in internally heated convection, is preferable to that of a hot anomaly, such as a plume head, carried far from the subduction zone. The nature of the western edge of the stagnant slab under northeast China has been investigated with modeling studies, which take into account the subduction history and the phase changes in the mantle. It is likely to be a ridge-type plate boundary between the extinct Izanagi plate and the Pacific plate. Thus, we have concluded that the slab gap under northeast China is not a breakage of the stagnant slab. Further studies have suggested that the existence of the rheological weakening of the slab in the transition zone, and the additional effects of a hot anomaly in the sub-slab mantle under the Pacific plate, may explain the differences in slab morphology under the northern Okhotsk arc and the northeast Japan arc.
Thermal Fatigue Study on the Divertor Plate Materials
NASA Astrophysics Data System (ADS)
Wu, Ji-hong; Zhang, Fu; Xu, Zeng-yu; Yan, Jian-cheng
2002-10-01
Thermal fatigue property of the divertor plate is one of the key issues that governs the lifetime of the divertor plate. Taking tungsten as surface material, a small-mock-up divertor plate was made by hot isostatic press welding (HIP). A thermal cycling experiment for divertor mock-up was carried out in the vacuum, where a high-heat-flux electronic gun was used as the thermal source. A cyclic heat flux of 9 MW/m2 was loaded onto the mock-up, a heating duration of 20 s was selected, the cooling water flow rate was 80 ml/s. After 1000 cycles, the surface and the W/Cu joint of the mock-up did not show any damage. The SEM was used to analyze the microstructure of the welding joint, where no cracks were found also.
Laser Shockwave Technique For Characterization Of Nuclear Fuel Plate Interfaces
DOE Office of Scientific and Technical Information (OSTI.GOV)
James A. Smith; Barry H. Rabin; Mathieu Perton
2012-07-01
The US National Nuclear Security Agency is tasked with minimizing the worldwide use of high-enriched uranium. One aspect of that effort is the conversion of research reactors to monolithic fuel plates of low-enriched uranium. The manufacturing process includes hot isostatic press bonding of an aluminum cladding to the fuel foil. The Laser Shockwave Technique (LST) is here evaluated for characterizing the interface strength of fuel plates using depleted Uranium/Mo foils. LST is a non-contact method that uses lasers for the generation and detection of large amplitude acoustic waves and is therefore well adapted to the quality assurance of this process.more » Preliminary results show a clear signature of well-bonded and debonded interfaces and the method is able to classify/rank the bond strength of fuel plates prepared under different HIP conditions.« less
Laser shockwave technique for characterization of nuclear fuel plate interfaces
DOE Office of Scientific and Technical Information (OSTI.GOV)
Perton, M.; Levesque, D.; Monchalin, J.-P.
2013-01-25
The US National Nuclear Security Agency is tasked with minimizing the worldwide use of high-enriched uranium. One aspect of that effort is the conversion of research reactors to monolithic fuel plates of low-enriched uranium. The manufacturing process includes hot isostatic press bonding of an aluminum cladding to the fuel foil. The Laser Shockwave Technique (LST) is here evaluated for characterizing the interface strength of fuel plates using depleted Uranium/Mo foils. LST is a non-contact method that uses lasers for the generation and detection of large amplitude acoustic waves and is therefore well adapted to the quality assurance of this process.more » Preliminary results show a clear signature of well-bonded and debonded interfaces and the method is able to classify/rank the bond strength of fuel plates prepared under different HIP conditions.« less
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-30
... rolling; simple hot-rolling of the cladding metal to ensure efficient welding to the basic metal; any... process to ensure welding (e.g., electrocladding), in which the cladding metal (nickel, chromium, etc.) is...
21 CFR 177.1010 - Acrylic and modified acrylic plastics, semirigid and rigid.
Code of Federal Regulations, 2014 CFR
2014-04-01
.... These are to be chosen as provided in § 176.170(c) of this chapter. (2) Preparation of samples... milliliters on a nonsparking, low-temperature hot plate and dried in 212 °F oven for 30 minutes. The residue...
Code of Federal Regulations, 2010 CFR
2010-07-01
..., or bending rolls; and hot or cold rolling mills. (ii) All pressing or punching machines, such as... presses; and plate punches. (iii) All bending machines, such as apron brakes and press brakes. (iv) All...
Solar hot water system installed at Day's Inn Motel, Dallas, Texas (Valley View)
NASA Technical Reports Server (NTRS)
1980-01-01
The solar system was designed to provide 65 percent of the total domestic hot water (DHW) demand. A liquid (water) flat plate collector (1,000 square feet) system automatically drains into the 1,000 gallon steel storage tank when the solar pump is not running. Heat is transferred from the DHW tanks through a shell and tube heat exchanger. A circulating pump between the DHW tanks and heat exchanger enables solar heated water to help make up standby losses. All pumps are controlled by differential temperature controllers.
Thermoelectric generator with hinged assembly for fins
Purdy, David L.; Shapiro, Zalman M.; Hursen, Thomas F.; Maurer, Gerould W.
1976-11-02
A cylindrical casing has a central shielded capsule of radioisotope fuel. A plurality of thermonuclear modules are axially arranged with their hot junctions resiliently pressed toward the shield and with their cold junctions adjacent a transition member having fins radiating heat to the environment. For each module, the assembly of transition member and fins is hinged to the casing for swinging to permit access to and removal of such module. A ceramic plate having gold layers on opposite faces prevents diffusion bonding of the hot junction to the shield.
Evaluation of the Analgesic Activity of the Methanolic Stem Bark Extract of Dialium Guineense (Wild)
Ezeja, MI; Omeh, YS; Ezeigbo, II; Ekechukwu, A
2011-01-01
Background: Dialium guineense is a medicinal plant used by some communities of Enugu-Ezike in Enugu State, Nigeria for treatment of fever, headache and other diverse ailments. Objectives: The present study evaluated the analgesic activity of the methanolic stem bark extract of the plant. Method: Acetic acid-induced abdominal constriction or writhing, tail immersion and hot plate analgesic models in albino Wistar mice were used for the study. Three test doses (250, 500, 1000 mg/kg body weight) of the extract were administered orally by gastric gavage. The activity was compared with a standard reference drug, acetylsalicylic acid (aspirin) (400 mg/kg) and negative control. The results were analysed by SPSS version 17 using ANOVA and Post Hoc Duncan. Result: In the acetic acid-induced writhing reflex model, D. guineense extract and the reference drug significantly (P =0.014 - 0.002) decreased the mean total number of abdominal constriction in the mice in a dose dependent fashion. The percentage inhibition of the abdominal constriction reflex was increased dose dependently from 0% in the negative control group to 71% at the highest dose of the extract (1000mg/kg). In the tail immersion model the extract at the dose of 1000 mg/kg significantly (P = 0. 048) increased the pain reaction time (PRT) while in hot plate model the extract and drug also significantly (P = 0.048 - 0.05) increased the mean PRT at the doses of 500 and 1000 mg/kg. The dose of 250 mg/kg showed no analgesic activity in tail immersion and hot plate models. Conclusion: Dialium guineense demonstrated significant analgesic activity that may be mediated through peripheral pain mechanism. PMID:23209955
Ezeja, Mi; Omeh, Ys; Ezeigbo, Ii; Ekechukwu, A
2011-01-01
Dialium guineense is a medicinal plant used by some communities of Enugu-Ezike in Enugu State, Nigeria for treatment of fever, headache and other diverse ailments. The present study evaluated the analgesic activity of the methanolic stem bark extract of the plant. Acetic acid-induced abdominal constriction or writhing, tail immersion and hot plate analgesic models in albino Wistar mice were used for the study. Three test doses (250, 500, 1000 mg/kg body weight) of the extract were administered orally by gastric gavage. The activity was compared with a standard reference drug, acetylsalicylic acid (aspirin) (400 mg/kg) and negative control. The results were analysed by SPSS version 17 using ANOVA and Post Hoc Duncan. In the acetic acid-induced writhing reflex model, D. guineense extract and the reference drug significantly (P =0.014 - 0.002) decreased the mean total number of abdominal constriction in the mice in a dose dependent fashion. The percentage inhibition of the abdominal constriction reflex was increased dose dependently from 0% in the negative control group to 71% at the highest dose of the extract (1000mg/kg). In the tail immersion model the extract at the dose of 1000 mg/kg significantly (P = 0. 048) increased the pain reaction time (PRT) while in hot plate model the extract and drug also significantly (P = 0.048 - 0.05) increased the mean PRT at the doses of 500 and 1000 mg/kg. The dose of 250 mg/kg showed no analgesic activity in tail immersion and hot plate models. Dialium guineense demonstrated significant analgesic activity that may be mediated through peripheral pain mechanism.
Flores, Juan A; El Banoua, Fadwa; Galán-Rodríguez, Beatriz; Fernandez-Espejo, Emilio
2004-07-01
The periaqueductal grey (PAG) area is involved in pain modulation as well as in opiate-induced anti-nociceptive effects. The PAG possess dopamine neurons, and it is likely that this dopaminergic network participates in anti-nociception. The objective was to further study the morphology of the PAG dopaminergic network, along with its role in nociception and opiate-induced analgesia in rats, following either dopamine depletion with the toxin 6-hydroxydopamine or local injection of dopaminergic antagonists. Nociceptive responses were studied through the tail-immersion (spinal reflex) and the hot-plate tests (integrated supraspinal response), establishing a cut-off time to further minimize animal suffering. Heroin and morphine were employed as opiates. Histological data indicated that the dopaminergic network of the PAG is composed of two types of neurons: small rounded cells, and large multipolar neurons. Following dopamine depletion of the PAG, large neurons (not small ones) were selectively affected by the toxin (61.9% dopamine cell loss, 80.7% reduction of in vitro dopaminergic peak), and opiate-induced analgesia in the hot-plate test (not the tail-immersion test) was reliably attenuated in lesioned rats (P < 0.01). After infusions of dopaminergic ligands into the PAG, D(1) (not D(2)) receptor antagonism attenuated opiate-induced analgesia in a dose-dependent manner in the hot-plate test. The present study provides evidence that large neurons of the dopaminergic network of the PAG participate in supraspinal (not spinal) nociceptive responses after opiates through the involvement of D(1) dopamine receptors. This dopaminergic system should be included as another network within the PAG involved in opiate-induced anti-nociception.
Microstructure and texture evolution in cold-rolled and annealed alloy MA-956
NASA Astrophysics Data System (ADS)
Hosoda, Takashi
The microstructural and texture development with thermomechanical processing, performed through a combination of cold-rolling and annealing, in MA-956 plate consisting of a layered and inhomogeneous microstructure was systematically assessed. The alloy contained in mass percent, 20 Cr, 4.8 Al, 0.4 Ti, 0.4 Y2O3, and the balance iron. The starting material was as-hot-rolled plate, 9.7 mm thick. The as-hot-rolled plate was subjected to 40%, 60%, and 80% cold-rolling reduction and subsequently annealed at 1000, 1200, or 1380. Assessment of microstructural and texture developments before and after cold-rolling and annealing was performed using light optical microscopy (LOM), Vickers hardness testing, and electron backscatter diffraction (EBSD). Locally introduced misorientations by cold-rolling in each region were evaluated by Kernel Average Misorientation (KAM) maps. The as-hot-rolled condition contained a layered and inhomogeneous microstructure consisting of thin and coarse elongated grains, and aggregated regions which consisted of fine grains and sub-grains with {100} texture parallel to the longitudinal direction. The microstructure of the 40% cold-rolled condition contained deformation bands, and the 60% and 80% cold-rolled conditions also contained highly deformed regions where the deformation bands were intricately tangled. A predominant orientation of (001) parallel to the rolling direction was developed during cold-rolling, becoming more prominent with increasing reduction. The magnitudes of KAM angles varied through the thickness depending on the initial microstructures. Recrystallization occurred in regions where high KAM angles were dense after annealing and nucleation sites were the aggregation regions, deformation bands, and highly deformed regions. The shape and size of the recrystallized grains varied depending on the nucleation sites.
Response of hot element flush wall gauges in oscillating laminar flow
NASA Technical Reports Server (NTRS)
Giddings, T. A.; Cook, W. J.
1986-01-01
The time dependent response characteristics of flush-mounted hot element gauges used as instruments to measure wall shear stress in unsteady periodic air flows were investigated. The study was initiated because anomalous results were obtained from the gauges in oscillating turbulent flows for the phase relation of the wall shear stress variation, indicating possible gauge response problems. Flat plate laminar oscillating turbulent flows characterized by a mean free stream velocity with a superposed sinusoidal variation were performed. Laminar rather than turbulent flows were studied, because a numerical solution for the phase angle between the free stream velocity and the wall shear stress variation that is known to be correct can be obtained. The focus is on comparing the phase angle indicated by the hot element gauges with corresponding numerical prediction for the phase angle, since agreement would indicate that the hot element gauges faithfully follow the true wall shear stress variation.
Solar hot water system installed at Day's Inn Motel, Savannah, Georgia
NASA Technical Reports Server (NTRS)
1980-01-01
The Solar System was designed to provide 50 percent of the total Domestic Hot Water (DHW) demand. Liquid Flat Plate Collectors (900 square feet) are used for the collector subsystem. The collector subsystem is closed loop, using 50 percent Ethylene Glycol solution antifreeze for freeze protection. The 1,000 gallon fiber glass storage tank contains two heat exchangers. One of the heat exchangers heats the storage tank with the collector solar energy. The other heat exchanger preheats the cold supply water as it passes through on the way to the Domestic Hot Water (DHW) tank heaters. Electrical energy supplements the solar energy for the DHW. The Collector Mounting System utilizes guy wires to structurally tie the collector array to the building.
Influence of Hot SPOT Features on the Shock Initiation of Heterogeneous Nitromethane
NASA Astrophysics Data System (ADS)
Dattelbaum, D. M.; Sheffield, S. A.; Stahl, D. B.; Dattelbaum, A. M.
2009-12-01
"Hot spots," or regions of localized high temperature and pressure that arise during the shock compression of heterogeneous materials, are known to highly influence the initiation characteristics of explosives. By introducing controlled-size particles at known number densities into otherwise homogeneous explosives, details about hot spot criticality can be mapped for a given material. Here, we describe a series of gas gun-driven plate impact experiments on nitromethane loaded with 40 μm silica beads at 6 wt%. Through the use of embedded electromagnetic gauges, we have gained insight into the initiation mechanisms as a function of the input shock pressure, and present a Pop-plot for the mixture, which is further compared to neat nitromethane.
Solar hot water systems application to the solar building test facility and the Tech House
NASA Technical Reports Server (NTRS)
Goble, R. L.; Jensen, R. N.; Basford, R. C.
1976-01-01
Projects which relate to the current national thrust toward demonstrating applied solar energy are discussed. The first project has as its primary objective the application of a system comprised of a flat plate collector field, an absorption air conditioning system, and a hot water heating system to satisfy most of the annual cooling and heating requirements of a large commercial office building. The other project addresses the application of solar collector technology to the heating and hot water requirements of a domestic residence. In this case, however, the solar system represents only one of several important technology items, the primary objective for the project being the application of space technology to the American home.
NASA Technical Reports Server (NTRS)
Storms, Bruce L.; Ross, James C.; Heineck, James T.; Walker, Stephen M.; Driver, David M.; Zilliac, Gregory G.; Bencze, Daniel P. (Technical Monitor)
2001-01-01
The 1/8-scale Ground Transportation System (GTS) model was studied experimentally in the NASA Ames 7- by 10-Ft Wind Tunnel. Designed for validation of computational fluid dynamics (CFD), the GTS model has a simplified geometry with a cab-over-engine design and no tractor-trailer gap. As a further simplification, all measurements of the GTS model were made without wheels. Aerodynamic boattail plates were also tested on the rear of the trailer to provide a simple geometry modification for computation. The experimental measurements include body-axis drag, surface pressures, surface hot-film anemometry, oil-film interferometry, and 3-D particle image velocimetry (PIV). The wind-averaged drag coefficient with and without boattail plates was 0.225 and 0.277, respectively. PIV measurements behind the model reveal a significant reduction in the wake size due to the flow turning provided by the boattail plates. Hot-film measurements on the side of the cab indicate laminar separation with turbulent reattachment within 0.08 trailer width for zero and +/- 10 degrees yaw. Oil film interferometry provided quantitative measurements of skin friction and qualitative oil flow images. A complete set of the experimental data and the surface definition of the model are included on a CD-ROM for further analysis and comparison.
NASA Astrophysics Data System (ADS)
Al-Damegh, Khaled; Sandvol, Eric; Al-Lazki, Ali; Barazangi, Muawia
2004-05-01
Continuous recordings of 17 broadband and short-period digital seismic stations from a newly established seismological network in Saudi Arabia, along with digital recordings from the broadband stations of the GSN, MEDNET, GEOFON, a temporary array in Saudi Arabia, and temporary short period stations in Oman, were analysed to study the lithospheric structure of the Arabian Plate and surrounding regions. The Arabian Plate is surrounded by a variety of types of plate boundaries: continental collision (Zagros Belt and Bitlis Suture), continental transform (Dead Sea fault system), young seafloor spreading (Red Sea and the Gulf of Aden) and oceanic transform (Owen fracture zone). Also, there are many intraplate Cenozoic processes such as volcanic eruptions, faulting and folding that are taking place. We used this massive waveform database of more than 6200 regional seismograms to map zones of blockage, inefficient and efficient propagation of the Lg and Sn phases in the Middle East and East Africa. We observed Lg blockage across the Bitlis Suture and the Zagros fold and thrust belt, corresponding to the boundary between the Arabian and Eurasian plates. This is probably due to a major lateral change in the Lg crustal waveguide. We also observed inefficient Lg propagation along the Oman mountains. Blockage and inefficient Sn propagation is observed along and for a considerable distance to the east of the Dead Sea fault system and in the northern portion of the Arabian Plate (south of the Bitlis Suture). These mapped zones of high Sn attenuation, moreover, closely coincide with extensive Neogene and Quaternary volcanic activity. We have also carefully mapped the boundaries of the Sn blockage within the Turkish and Iranian plateaus. Furthermore, we observed Sn blockage across the Owen fracture zone and across some segments of the Red Sea. These regions of high Sn attenuation most probably have anomalously hot and possibly thin lithospheric mantle (i.e. mantle lid). A surprising result is the efficient propagation of Sn across a segment of the Red Sea, an indication that active seafloor spreading is not continuous along the axis of the Red Sea. We also investigated the attenuation of Pn phase (QPn) for 1-2 Hz along the Red Sea, the Dead Sea fault system, within the Arabian Shield and in the Arabian Platform. Consistent with the Sn attenuation, we observed low QPn values of 22 and 15 along the western coast of the Arabian Plate and along the Dead Sea fault system, respectively, for a frequency of 1.5 Hz. Higher QPn values of the order of 400 were observed within the Arabian Shield and Platform for the same frequency. Our results based on Sn and Pn observations along the western and northern portions of the Arabian Plate imply the presence of a major anomalously hot and thinned lithosphere in these regions that may be caused by the extensive upper mantle anomaly that appears to span most of East Africa and western Arabia.
The African Plate: A history of oceanic crust accretion and subduction since the Jurassic
NASA Astrophysics Data System (ADS)
Gaina, C.; Torsvik, T. H.; Labails, C.; van Hinsbergen, D.; Werner, S.; Medvedev, S.
2012-04-01
Initially part of Gondwana and Pangea, and now surrounded almost entirely by spreading centres, the African plate moved relatively slowly for the last 200 million years. Yet both Africa's cratons and passive margins were affected by tectonic stresses developed at distant plate boundaries. Moreover, the African plate was partly underlain by hot mantle (at least for the last 300 Ma) - either a series of hotspots or a superswell, or both - that contributed to episodic volcanism, basin-swell topography, and consequent sediment deposition, erosion, and structural deformation. A systematic study of the African plate boundaries since the opening of surrounding oceanic basins is presently lacking. This is mainly because geophysical data are sparse and there are still controversies regarding the ages of oceanic crust. The publication of individual geophysical datasets and more recently, global Digital Map of Magnetic Anomalies (WDMAM, EMAG2) prompted us to systematically reconstruct the ages and extent of oceanic crust around Africa for the last 200 Ma. Location of Continent Ocean Boundary/Continent Ocean Transition and older oceanic crust (Jurassic and Cretaceous) are updates in the light of gravity, magnetic and seismic data and models of passive margin formation. Reconstructed NeoTethys oceanic crust is based on a new model of microcontinent and intr-oceanic subduction zone evolution in this area.The new set of oceanic palaeo-age grid models constitutes the basis for estimating the dynamics of oceanic crust through time and will be used as input for quantifying the paleo-ridge push and slab pull that contributed to the African plate palaeo-stresses and had the potential to influence the formation of sedimentary basins.
Analgesic properties of Capraria biflora leaves aqueous extract.
Acosta, S L; Muro, L V; Sacerio, A L; Peña, A R; Okwei, S N
2003-12-01
The analgesic properties of dried leaves of Capraria biflora were investigated. The aqueous extract (50-200 mg kg(-1)) produced moderate inhibition of acetic acid-induced writhing in mice. At the same doses, a better analgesic effect was observed on the hot plate test.
NASA Technical Reports Server (NTRS)
Schopper, M. R.
1982-01-01
The hot-wire anemometer amplitude data contained in the 1977 report of P. J. Shapiro entitled, ""The Influence of Sound Upon Laminar Boundary'' were reevaluated. Because the low-Reynolds number boundary layer disturbance data were misinterpreted, an effort was made to improve the corresponding disturbance growth rate curves. The data are modeled as the sum of upstream and downstream propagating acoustic waves and a wave representing the Tollmien-Schlichting (TS) wave. The amplitude and phase velocity of the latter wave were then adjusted so that the total signal reasonably matched the amplitude and phase angle hot-wire data along the plate laminar boundary layer. The revised rates show growth occurring further upstream than Shapiro found. It appears that the premature growth is due to the adverse pressure gradient created by the shape of the plate. Basic elements of sound propagation in ducts and the experimental and theoretical acoustic-stability literature are reviewed.
Anti-inflammatory, Analgesic and Antiulcer properties of Porphyra vietnamensis.
Bhatia, Saurabh; Sharma, Kiran; Sharma, Ajay; Nagpal, Kalpana; Bera, Tanmoy
2015-01-01
Aim of the present work was to investigate the anti-inflammatory, analgesic and antiulcer effects of red seaweed Porphyra vietnamensis (P. vietnamenis). Aqueous (POR) and alcoholic (PE) fractions were successfully isolated from P. vietnamenis. Further biological investigations were performed using a classic test of paw edema induced by carrageenan, writhing induced by acetic acid, hot plate method and naproxen induced gastro-duodenal ulcer. Among the fractions POR showed better activity. POR and PE significantly (p < 0.05) reduced carrageenan induced paw edema in a dose dependent manner. In the writhing test POR significantly (p < 0.05) reduced abdominal writhes than PE. In hot plate method POR showed better analgesic activity than PE. POR showed comparable ulcers reducing potential (p<0.01) to that of omeprazole, and has more ulcer reducing potential then PE. The results of this study demonstrated that P. vietnamenis aqueous fraction possesses biological activity that is close to the standards taken for the treatment of peripheral painful or/and inflammatory and ulcer conditions.
Solar project description for Loyola University-Biever Hall men's dormitory, New Orleans, Louisiana
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1981-07-10
The Loyola University solar energy system, located in New Orleans, Louisiana, preheats approximately 9000 gallons of domestic hot water (DHW) each day to Biever Hall Dormitory. Biever Hall is a six-story dormitory that houses 420 students. The system is designed to supply 140/sup 0/F water to bathrooms, showers, and eight washing machines. The solar energy system has 15 arrays of flat-plate collectors with a gross area of 4590 square feet. The system is an open loop system which uses potable water as both the collector fluid and storage medium. City water is preheated by flat plate collectors on the roofmore » and stored in a 5000 gallon tank located on the west side of the building at ground level. Upon demand the preheated water is transported to two existing 1500 gallon hot water tanks. Auxiliary energy is supplied by a central heating plant via a high temperature/high pressure line.« less
[Hemostatic and analgesic effect of Gonghuan Zhixue Tablet on mice].
Fu, Ling-Mei; You, Zhao-Ling; Lei, Lei; Wen, Le-Xi; Chen, Huan-Ming
2004-03-01
To explore the hemostatic and analgesic effect of Gonghuan Zhixue Tablet (GHZXT) on mice and to produce experimental evidence for exploiting new drug for endometrorrhagia caused by Cu-intrauterine contraceptive device (Cu-IUD). Compared with 6-aminocaproic acid and notoginseng, the effects of GHZXT on clotting and bleeding time of mice with capillary method and severed tail were investigated; and compared with aspirin, the analgesic effects of GHZXT on mice were investigated with hot plate and torsive body method. The clotting time of mice was remarkably shortened with a rising of the dosage of GHZXT and the difference between each therapeutic group and distilled water group was remarkable. As compared with distilled water group, the bleeding time of each dosage group of GHZXT was obviously shortened; and each dosage of GHZXT could prolong the time of pain reaction to hot plate and decrease the degree of torsive body of the mice. Pharmacological experiment has proved that GHZXT has evident hemostatic and analgesic function.
Anti-inflammatory, Analgesic and Antiulcer properties of Porphyra vietnamensis
Bhatia, Saurabh; Sharma, Kiran; Sharma, Ajay; Nagpal, Kalpana; Bera, Tanmoy
2015-01-01
Objectives: Aim of the present work was to investigate the anti-inflammatory, analgesic and antiulcer effects of red seaweed Porphyra vietnamensis (P. vietnamenis). Materials and Methods: Aqueous (POR) and alcoholic (PE) fractions were successfully isolated from P. vietnamenis. Further biological investigations were performed using a classic test of paw edema induced by carrageenan, writhing induced by acetic acid, hot plate method and naproxen induced gastro-duodenal ulcer. Results: Among the fractions POR showed better activity. POR and PE significantly (p < 0.05) reduced carrageenan induced paw edema in a dose dependent manner. In the writhing test POR significantly (p < 0.05) reduced abdominal writhes than PE. In hot plate method POR showed better analgesic activity than PE. POR showed comparable ulcers reducing potential (p<0.01) to that of omeprazole, and has more ulcer reducing potential then PE. Conclusions: The results of this study demonstrated that P. vietnamenis aqueous fraction possesses biological activity that is close to the standards taken for the treatment of peripheral painful or/and inflammatory and ulcer conditions. PMID:25767759
Heidari, M R; Foroumadi, A; Amirabadi, A; Samzadeh-Kermani, A; Azimzadeh, B S; Eskandarizadeh, A
2009-08-01
There have been many reports indicating the analgesic and anti-inflammatory effects of 3,4-dihydroxychalcones. We have designed and synthesized a rigid 3,4-dihydroxychalcone (RDHC) as a possible drug effecting inflammation and nociception. The analgesic and anti-inflammatory effects were evaluated by formalin and hot-plate tests, respectively. The results showed that RDHC induced significant antinociceptive and anti-inflammatory effects (P < 0.01). Maximum analgesia (63.7%) was observed at 37.5 mg/kg in the first phase of the formalin test. The effect of RDHC was higher in the chronic phase (inflammation phase) of the formalin test (86.4%, P < 0.01). In addition, a significant analgesia (maximum possible effect; MPE = 30.1%) was observed in the hot plate test 45 min after injection of 37.5 mg/kg RDHC (P < 0.01). As a result of our findings, this new RDHC could be suggested for further pharmacological studies.
Mothana, Ramzi; Alsaid, Mansour; Khaled, Jamal M; Alharbi, Naiyf S; Alatar, Abdulrahman; Raish, Mohammad; Al-Yahya, Mohammed; Rafatullah, Syed; Parvez, Mohammad Khalid; Ahamad, Syed Rizwan
2016-03-01
This study was designed to investigate the possible antiniciceptive, antipyretic and antimicrobial activities of the essential oil obtained from the fruits of Piper Cubeba (L.). To assess the antinociceptive and antipyretic activities, three doses (150, 300 and 600 mg/kg, i.p.) were tested in acetic acid-induced abdominal writhing, tail flick reaction and hot-plate and Brewer's yeast-induced hyperpyrexia test models in animals. Moreover, the antimicrobial activity was examined using agar diffusion method and broth micro-dilution assay for minimum inhibitory concentrations (MIC). The Piper Cubeba essential oil (PCEO) showed a marked antinociception (17, 30 and 54%) and an increase in reaction time in mice in the flick tailed and hot-plate tests. The brewer's yeast induced hyperpyrexia was decreased in a dose dependent manner. PCEO also exhibited a strong antimicrobial potential. These findings confirm the traditional analgesic indications of P. cubeba oil and provide persuasive evidence and support its use in Arab traditional medicine.
Hybrid thermoelectric solar collector design and analysis
NASA Technical Reports Server (NTRS)
Roberts, A. S., Jr.; Shaheen, K. E.
1982-01-01
A flat-plate solar collector is conceived where energy cascades through thermoelectric power modules generating direct-current electricity. The intent of this work was to choose a collector configuration and to perform a steady-state thermal performance assessment. A set of energy balance equations were written and solved numerically for the purpose of optimizing collector thermal and electrical performance. The collector design involves finned columns of thermoelectric modules imbedded in the absorber plate (hot junction) over a parallel array of vertical tubes. The thermoelectric power output is limited by the small hot-junction/cold-junction temperature difference which can be maintained under steady-state conditions. The electric power per unit tube pass area is found to have a maximum as a function of a geometric parameter, while electric power is maximized with respect to an electric resistance ratio. Although the electric power efficiency is small, results indicate that there is sufficient electric power production to drive a coolant circulator, suggesting the potential for a stand-alone system.
Almeida, Jackson Roberto Guedes da Silva; Souza, Grasielly Rocha; Silva, Juliane Cabral; Saraiva, Sarah Raquel Gomes de Lima; Júnior, Raimundo Gonçalves de Oliveira; Quintans, Jullyana de Souza Siqueira; Barreto, Rosana de Souza Siqueira; Bonjardim, Leonardo Rigoldi; Cavalcanti, Sócrates Cabral de Holanda; Junior, Lucindo José Quintans
2013-01-01
Borneol, a bicyclic monoterpene, has been evaluated for antinociceptive and anti-inflammatory activities. Antinociceptive and anti-inflammatory activities were studied by measuring nociception by acetic acid, formalin, hot plate, and grip strength tests, while inflammation was prompted by carrageenan-induced peritonitis. The rotarod test was used to evaluate motor coordination. Borneol produced a significant (P < 0.01) reduction of the nociceptive behavior at the early and late phases of paw licking and reduced the writhing reflex in mice (formalin and writhing tests, resp.). When the hot plate test was conducted, borneol (in higher dose) produced an inhibition (P < 0.05) of the nociceptive behavior. Such results were unlikely to be provoked by motor abnormality. Additionally, borneol-treated mice reduced the carrageenan-induced leukocytes migration to the peritoneal cavity. Together, our results suggest that borneol possess significant central and peripheral antinociceptive activity; it has also anti-inflammatory activity. In addition, borneol did not impair motor coordination. PMID:23710149
NASA Astrophysics Data System (ADS)
Stratton, Zachary T.
The film-cooling holes in turbine blades are fed from an internal cooling channel. This channel imposes a crossflow at the entrance of the holes that can significantly affect the performance of the cooling jets that emanate from those holes. In this study, CFD simulations based on steady RANS with the shear-stress transport (SST) and the realizable k-epsilon turbulence models were performed to study film cooling of a flat plate with cooling jets issuing from eight round holes with a compound angle of 45 degrees, where the coolant channel that fed the cooling jets was oriented perpendicular to the direction of the hot-gas flow. One case was also performed by using large-eddy simulation (LES) to get a sense of the unsteady nature of the flow. Operating conditions were chosen to match the laboratory conditions, which maintained a density ratio of 1.5 between the coolant and the hot gas. Parameters studied include internal crossflow direction and blowing ratios of 0.5, 1.0, and 1.5. Results obtained showed an unsteady vortex forms inside the hole, causing a side-to-side shedding of the coolant jet. Values of adiabatic effectiveness predicted by the CFD simulations were compared with experimentally measured values. Steady RANS was found to be inconsistent in its ability to predict adiabatic effectiveness with relative error ranging from 10% to over 100%. LES was able to predict adiabatic effectiveness with reasonable accuracy.
Correlation of analytical and experimental hot structure vibration results
NASA Technical Reports Server (NTRS)
Kehoe, Michael W.; Deaton, Vivian C.
1993-01-01
High surface temperatures and temperature gradients can affect the vibratory characteristics and stability of aircraft structures. Aircraft designers are relying more on finite-element model analysis methods to ensure sufficient vehicle structural dynamic stability throughout the desired flight envelope. Analysis codes that predict these thermal effects must be correlated and verified with experimental data. Experimental modal data for aluminum, titanium, and fiberglass plates heated at uniform, nonuniform, and transient heating conditions are presented. The data show the effect of heat on each plate's modal characteristics, a comparison of predicted and measured plate vibration frequencies, the measured modal damping, and the effect of modeling material property changes and thermal stresses on the accuracy of the analytical results at nonuniform and transient heating conditions.
NASA Technical Reports Server (NTRS)
Oliver, A. B.; Lillard, R. P.; Blaisdell, G. A.; Lyrintizis, A. S.
2006-01-01
The capability of the OVERFLOW code to accurately compute high-speed turbulent boundary layers and turbulent shock-boundary layer interactions is being evaluated. Configurations being investigated include a Mach 2.87 flat plate to compare experimental velocity profiles and boundary layer growth, a Mach 6 flat plate to compare experimental surface heat transfer,a direct numerical simulation (DNS) at Mach 2.25 for turbulent quantities, and several Mach 3 compression ramps to compare computations of shock-boundary layer interactions to experimental laser doppler velocimetry (LDV) data and hot-wire data. The present paper describes outlines the study and presents preliminary results for two of the flat plate cases and two small-angle compression corner test cases.
Anomalous heat transport and condensation in convection of cryogenic helium
Urban, Pavel; Schmoranzer, David; Hanzelka, Pavel; Sreenivasan, Katepalli R.; Skrbek, Ladislav
2013-01-01
When a hot body A is thermally connected to a cold body B, the textbook knowledge is that heat flows from A to B. Here, we describe the opposite case in which heat flows from a colder but constantly heated body B to a hotter but constantly cooled body A through a two-phase liquid–vapor system. Specifically, we provide experimental evidence that heat flows through liquid and vapor phases of cryogenic helium from the constantly heated, but cooler, bottom plate of a Rayleigh–Bénard convection cell to its hotter, but constantly cooled, top plate. The bottom plate is heated uniformly, and the top plate is cooled by heat exchange with liquid helium maintained at 4.2 K. Additionally, for certain experimental conditions, a rain of helium droplets is detected by small sensors placed in the cell at about one-half of its height. PMID:23576759
Thermal structure of the Kanto region, Japan
NASA Astrophysics Data System (ADS)
Wada, Ikuko; He, Jiangheng
2017-07-01
Using a 3-D numerical thermal model, we investigate the thermal structure of the Kanto region of Japan where two oceanic plates subduct. In a typical subduction setting with one subducting slab, the motion of the slab drives solid-state mantle flow in the overlying mantle wedge, bringing in hot mantle from the back-arc toward the forearc. Beneath Kanto, however, the presence of the subducting Philippine Sea plate between the overlying North American plate and the subducting Pacific plate prevents a typical mantle wedge flow pattern, resulting in a cooler condition. Further, frictional heating and the along-margin variation in the maximum depth of slab-mantle decoupling along the Pacific slab surface affect the thermal structure significantly. The model provides quantitative estimates of spatial variations in the temperature condition that are consistent with the observed surface heat flow pattern and distributions of interplate seismicity and arc volcanoes in Kanto.
Dima, Giovanna; Verzera, Antonella; Grob, Koni
2011-11-01
Party plates made of recycled paperboard with a polyolefin film on the food contact surface (more often polypropylene than polyethylene) were tested for migration of mineral oil into various foods applying reasonable worst case conditions. The worst case was identified as a slice of fried meat placed onto the plate while hot and allowed to cool for 1 h. As it caused the acceptable daily intake (ADI) specified by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) to be exceeded, it is concluded that recycled paperboard is generally acceptable for party plates only when separated from the food by a functional barrier. Migration data obtained with oil as simulant at 70°C was compared to the migration into foods. A contact time of 30 min was found to reasonably cover the worst case determined in food.
Core assembly storage structure
Jones, Jr., Charles E.; Brunings, Jay E.
1988-01-01
A structure for the storage of core assemblies from a liquid metal-cooled nuclear reactor. The structure comprises an enclosed housing having a substantially flat horizontal top plate, a bottom plate and substantially vertical wall members extending therebetween. A plurality of thimble members extend downwardly through the top plate. Each thimble member is closed at its bottom end and has an open end adjacent said top plate. Each thimble member has a length and diameter greater than that of the core assembly to be stored therein. The housing is provided with an inlet duct for the admission of cooling air and an exhaust duct for the discharge of air therefrom, such that when hot core assemblies are placed in the thimbles, the heat generated will by convection cause air to flow from the inlet duct around the thimbles and out the exhaust duct maintaining the core assemblies at a safe temperature without the necessity of auxiliary powered cooling equipment.
Geodynamic modelling of low-buoyancy thermo-chemical plumes
NASA Astrophysics Data System (ADS)
Dannberg, Juliane; Sobolev, Stephan
2015-04-01
The Earth's biggest magmatic events that form Large Igneous Provinces are believed to originate from massive melting when hot mantle plumes rising from the lowermost mantle reach the base of the lithosphere. Classical models of thermal mantle plumes predict a flattening of the plume head to a disk-like structure, a kilometer-scale surface uplift just before the initiation of LIPs and thin plume tails. However, there are seismic observations and paleo-topography data that are difficult to explain with this classical approach. Here, using numerical models, we show that the issue can be resolved if major mantle plumes are thermo-chemical rather than purely thermal. It has been suggested a long time ago that subducted oceanic crust could be recycled by mantle plumes; and based on geochemical data, they may contain up to 15-20% of this recycled material in the form of dense eclogite, which drastically decreases their buoyancy and makes it depth-dependent. We perform numerical experiments in a 3D spherical shell geometry to investigate the dynamics of the plume ascent, the interaction between plume- and plate-driven flow and the dynamics of melting in a plume head. For this purpose, we use the finite-element code ASPECT, which allows for complex temperature-, pressure- and composition-dependent material properties. Moreover, our models incorporate phase transitions (including melting) with the accompanying rheological and density changes, Clapeyron slopes and latent heat effects for both peridotite and eclogite, mantle compressibility and a strong temperature- and depth-dependent viscosity. We demonstrate that despite their low buoyancy, such plumes can rise through the whole mantle causing only negligible surface uplift. Conditions for this ascent are high plume volume and moderate lower mantle subadiabaticity. While high plume buoyancy results in plumes directly advancing to the base of the lithosphere, plumes with slightly lower buoyancy pond in a depth of 300-400 km and form pools or a second layer of hot material. These structures are caused by phase transitions occurring in different depths in peridotite and eclogite; and they become asymmetric and finger-like channels begin to form when the plume gets entrained by a quickly moving overlying plate. We also show that the bulky tails of large and hot low-buoyancy plumes are stable for several tens of millions of years and that their shapes fit seismic tomography data much better than the narrow tails of thermal plumes.
Influences of powder granularity on crystallizing characteristics in mica-contained glass ceramic
NASA Astrophysics Data System (ADS)
Xu, L. N.; Kong, D. Y.; Tian, Q. B.; Lv, Z. J.
2017-09-01
A machinable mica-contained glass ceramic in the SiO2-Al2O3-MgO-F glassy system was prepared by ball milling and hot pressed sintering. Three kinds of powder sizes of base glass were chosen and the effects of the glass powder sizes on the crystallization were explored by x-ray diffraction and scanning electron microscopy techniques. The results indicate that mica crystal as a major phase and KFeSi2O6 and mullite as minor phases are crystallized. Applying pressure at 670°C has little influences on the types of crystal precipitated and the preferential growth of crystal. The powder sizes, however, have obvious effects on the morphology of precipitated mica crystals. In the glass sample with a powder size of d50=16.4 µm, the plate-shaped mica phase is precipitated. As the powder size decrease to 9.9 µm and 3.3 µm, however, the particle-shaped mica is formed instead of the plate-shaped crystals.
Velocity profile of water vapor inside a cavity with two axial inlets and two outlets
NASA Astrophysics Data System (ADS)
Guadarrama-Cetina, José; Ruiz Chavarría, Gerardo
2014-03-01
To study the dynamics of Breath Figure phenomenon, a control of both the rate of flow and temperature of water vapor is required. The experimental setup widely used is a non hermetically closed chamber with cylindrical geometry and axial inlets and outlets. In this work we present measurements in a cylindrical chamber with diameter 10 cm and 1.5 cm height, keeping a constant temperature (10 °C). We are focused in the velocity field when a gradient of the temperatures is produced between the base plate and the vapor. With a flux of water vapor of 250 mil/min at room temperature (21 °C), the Reynolds number measured in one inlet is 755. Otherwise, the temperatures of water vapor varies from 21 to 40 °C. The velocity profile is obtained by hot wire anemometry. We identify the stagnations and the possibly instabilities regions for an empty plate and with a well defined shape obstacle as a fashion sample. Facultad de Ciencias, UNAM.
New Energy Villages in Taiwan and China
NASA Astrophysics Data System (ADS)
Lee, C. S.; Wang, S. C.
2015-12-01
Taiwan locates in the active tectonic subdution and collision belts, therefore, the geothermal gradient is very high and have found 128 sites of high geothermal areas; 20% of them have the temperature between 75 - 200 degree C in which they can be directly used for the electricity generation; 50% of them are in 50 - 74 degree C and the rest 30% are below 50 degree C. These areas need the deep drillings to get into higher temperature for power energy. The first 20% high temperature areas are mostly located in the coastal or mountain regions. The government is interesting to develop these areas as the "New Energy Villages" so that they can not only become self-energy sufficient sites, but also to protect themself from being the loss of electricity and water during the typhoon and earthquake hazards. The multiple usages of hot water (such as the first power generation and then the hot spring utilization) have its merits. China, in the other hand, is not within the present-day active tectonic zone. However, the recent Sino Probe Experiments (Deep Exploration in China) have mapped the Cetaceous plate boundaries in the coast of China. The heat is still possibly migrating to near the surface through the existing structures. For example, the Feng Shun Geothermal Power Station in north of Guangzhou, Guangdong Province, used the 96 degree C hot water from a well of 800 m producing a small amount of 300 KW power since 1984. The Guangdong Province is located in the edge of Mesozoic South China Plate. Further in land, the Huang Mountain, one of the world heritage sites, is located at the boundary of another Mesozoic Yangtze River Plate. There is not a geothermal power plant; however, a number of hot springs are in a booming tour business at the foot hill of the mountain. The electricity has to come from a long way of net working. If China develops the local, small, but sufficient power plants by using the modern geothermal exploration and drilling techniques. The "New Energy Villages" will be benefit to the energy and environment need.
The Physical Reality of Molecules: They're Dense and They Move Around!
ERIC Educational Resources Information Center
Silverstein, Todd P.
1995-01-01
Describes a simple and graphic demonstration of molecular motion that utilizes a hot plate, a beaker, tap water, India ink, and a Pasteur pipette with a rubber bulb. Provides tips on guiding students to an understanding of molecular motion using this demonstration. (DDR)
Polydiacetylenes: An Ideal Color System for Teaching Polymer Science.
ERIC Educational Resources Information Center
Patel, Gordhan N.; Yang, Nan-Loh
1983-01-01
Describes 14 experiments that illustrate, via color changes, a broad scope of fundamental phenomena in polymer science. The experiments, suitable for high school through graduate level, require only test tubes, filter paper, heat source (hot plate or hair drier), and ultra-violet light source. (JN)
NASA Astrophysics Data System (ADS)
Defrianto; Tambunan, W.; Lazuardi
2017-07-01
The use of waste heat from exhaust gas and converting it to electricity is now an alternative to harvest a cheap and clean energy. Thermoelectric generator (TEG) has the ability to directly recover such waste heat and generate electricity. The aim of this study is to simulate the heat transfer on the aluminum adapter plate for homogeneity temperature distribution coupled with hot side of TEG type 40-40-10/100 from Firma Eureka and adjust their high temperatures to the TEG operating temperature to avoid the element damage. Modelling was carried out using MATLAB modified diffusion equation with Dirichlet boundary conditions at defined temperature which has been set at the ends of the heat source at 463K and 373K ± 10% on the hot side of the TEG element. The use of nylon insulated material is modeled after Neumann boundary condition in which the temperature gradient is ∂T/∂n = 0 out of boundary. Realization of the modelling is done by designing a heat conductive plate using software ACAD 2015 and converted into a binary file format of Mathlab to form a finite element mesh with geometry variations of solid model. The solid cubic model of aluminum adapter plate has a dimension of 40mm length, 40mm width and also 20mm, 30mm and 40mm thickness arranged in two arrays of 2×2 and 2×3 of TEG elements. Results showed a temperature decrease about 40.95% and 50.02% respectively from the initial source and appropriate with TEG temperature tolerance.
NASA Astrophysics Data System (ADS)
Bunge, H.; Schuberth, B. S.; Shephard, G. E.; Müller, D.
2010-12-01
Plate and plume flow are dominant modes of mantle convection, as pointed out by Geoff Davies early on. Driven, respectively, from a cold upper and a hot lower thermal boundary layer these modes are now sufficiently well imaged by seismic tomographers to exploit the thermal boundary layer concept as an effective tool in exploring two long standing geodynamic problems. One relates to the choice of an absolute reference frame in plate tectonic reconstructions. Several absolute reference frames have been proposed over the last decade, including those based on hotspot tracks displaying age progression and assuming either fixity or motion, as well as palaeomagnetically-based reference frames, a subduction reference frame and hybrid versions. Each reference frame implies a particular history of the location of subduction zones through time and thus the evolution of mantle heterogeneity via mixing of subducted slab material in the mantle. Here we compare five alternative absolute plate motion models in terms of their consequences for deep mantle structure. Taking global paleo-plate boundaries and plate velocities back to 140 Ma derived from the new plate tectonic reconstruction software GPlates and assimilating them into vigorous 3-D spherical mantle circulation models, we infer geodynamic mantle heterogeneity and compare it to seismic tomography for each absolute rotation model. We also focus on the challenging problem of interpreting deep mantle seismic heterogeneity in terms of thermal and compositional variations. Using published thermodynamically self-consistent mantle mineralogy models in the pyrolite composition, we find strong plume flux from the CMB, with a high temperature contrast (on the order of 1000 K) across the lower thermal boundary layer is entirely sufficient to explain elastic heterogeneity in the deep mantle for a number of quantitative measures. A high excess temperatures of +1000--1500 K for plumes in the lowermost mantle is particularly important in understanding the strong seismic velocity reduction mapped by tomography in low-velocity bodies of the deep mantle, as this produces significant negative anomalies of shear wave velocity of up to -4%. We note, however, that our results do not account for the curious observation of seismic anti-correlation, which appears difficult to explain in any case. Our results provide important constraints for the integration of plate tectonics and mantle dynamics and their use in forward and inverse geodynamic mantle models.
The Uses and Impacts of Mobile Computing Technology in Hot Spots Policing.
Koper, Christopher S; Lum, Cynthia; Hibdon, Julie
2015-12-01
Recent technological advances have much potential for improving police performance, but there has been little research testing whether they have made police more effective in reducing crime. To study the uses and crime control impacts of mobile computing technology in the context of geographically focused "hot spots" patrols. An experiment was conducted using 18 crime hot spots in a suburban jurisdiction. Nine of these locations were randomly selected to receive additional patrols over 11 weeks. Researchers studied officers' use of mobile information technology (IT) during the patrols using activity logs and interviews. Nonrandomized subgroup and multivariate analyses were employed to determine if and how the effects of the patrols varied based on these patterns. Officers used mobile computing technology primarily for surveillance and enforcement (e.g., checking automobile license plates and running checks on people during traffic stops and field interviews), and they noted both advantages and disadvantages to its use. Officers did not often use technology for strategic problem-solving and crime prevention. Given sufficient (but modest) dosages, the extra patrols reduced crime at the hot spots, but this effect was smaller in places where officers made greater use of technology. Basic applications of mobile computing may have little if any direct, measurable impact on officers' ability to reduce crime in the field. Greater training and emphasis on strategic uses of IT for problem-solving and crime prevention, and greater attention to its behavioral effects on officers, might enhance its application for crime reduction. © The Author(s) 2016.
NASA Technical Reports Server (NTRS)
1980-01-01
The solar system was designed to provide 47 percent of the space heating, 8,800 square feet area and 75 percent of the domestic hot water (DHW) load. The solar system consists of 2,808 square feet of Solaron, model 2001, air, flat plate collector subsystem, a concrete box storage subsystem which contains 1,428 cubic feet of 0.5 inch diameter pebbles weighing 71.5 tons, a DHW preheat tank, blowers, pumps, heat exchangers, air ducting, controls and associated plumbing. Two 120 gallon electric DHW heaters supply domestic hot water which is preheated by the solar system. Auxiliary space heating is provided by three electric heat pumps with electric resistance heaters and four 30 kilowatt electric unit heaters. There are six modes of system operation.
Solar hot water system installed at Quality Inn, Key West, Florida
NASA Astrophysics Data System (ADS)
1980-04-01
The solar energy hot water system installed in the Quality Inn, Key West, Florida, which consists of four buildings is described. Three buildings are low-rise, two-story buildings containing 100 rooms. The fourth is a four-story building with 48 rooms. The solar system was designed to provide approximately 50 percent of the energy required for the domestic hot water system. The solar system consists of approximately 1400 square feet of flat plate collector, two 500 gallon storage tanks, a circulating pump, and a controller. Operation of the system was begun in April 1978, and has continued to date with only three minor interruptions for pump repair. In the first year of operation, it was determined that the use of the solar facility resulted in forty percent fuel savings.
Solar hot water system installed at Quality Inn, Key West, Florida
NASA Technical Reports Server (NTRS)
1980-01-01
The solar energy hot water system installed in the Quality Inn, Key West, Florida, which consists of four buildings is described. Three buildings are low-rise, two-story buildings containing 100 rooms. The fourth is a four-story building with 48 rooms. The solar system was designed to provide approximately 50 percent of the energy required for the domestic hot water system. The solar system consists of approximately 1400 square feet of flat plate collector, two 500 gallon storage tanks, a circulating pump, and a controller. Operation of the system was begun in April 1978, and has continued to date with only three minor interruptions for pump repair. In the first year of operation, it was determined that the use of the solar facility resulted in forty percent fuel savings.
NASA Astrophysics Data System (ADS)
Simoni, Daniele; Lengani, Davide; Guida, Roberto
2016-09-01
The transition process of the boundary layer growing over a flat plate with pressure gradient simulating the suction side of a low-pressure turbine blade and elevated free-stream turbulence intensity level has been analyzed by means of PIV and hot-wire measurements. A detailed view of the instantaneous flow field in the wall-normal plane highlights the physics characterizing the complex process leading to the formation of large-scale coherent structures during breaking down of the ordered motion of the flow, thus generating randomized oscillations (i.e., turbulent spots). This analysis gives the basis for the development of a new procedure aimed at determining the intermittency function describing (statistically) the transition process. To this end, a wavelet-based method has been employed for the identification of the large-scale structures created during the transition process. Successively, a probability density function of these events has been defined so that an intermittency function is deduced. This latter strictly corresponds to the intermittency function of the transitional flow computed trough a classic procedure based on hot-wire data. The agreement between the two procedures in the intermittency shape and spot production rate proves the capability of the method in providing the statistical representation of the transition process. The main advantages of the procedure here proposed concern with its applicability to PIV data; it does not require a threshold level to discriminate first- and/or second-order time-derivative of hot-wire time traces (that makes the method not influenced by the operator); and it provides a clear evidence of the connection between the flow physics and the statistical representation of transition based on theory of turbulent spot propagation.
Zhang, Ren-Hua; Su, Hong-Bo; Tian, Jing; Mi, Su-Juan; Li, Zhao-Liang
2016-06-24
In the inversion of land surface temperature (LST) from satellite data, obtaining the information on land surface emissivity is most challenging. How to solve both the emissivity and the LST from the underdetermined equations for thermal infrared radiation is a hot research topic related to quantitative thermal infrared remote sensing. The academic research and practical applications based on the temperature-emissivity retrieval algorithms show that directly measuring the emissivity of objects at a fixed thermal infrared waveband is an important way to close the underdetermined equations for thermal infrared radiation. Based on the prior research results of both the authors and others, this paper proposes a new approach of obtaining the spectral emissivity of the object at 8-14 µm with a single-band CO₂ laser at 10.6 µm and a 102F FTIR spectrometer. Through experiments, the spectral emissivity of several key samples, including aluminum plate, iron plate, copper plate, marble plate, rubber sheet, and paper board, at 8-14 µm is obtained, and the measured data are basically consistent with the hemispherical emissivity measurement by a Nicolet iS10 FTIR spectrometer for the same objects. For the rough surface of materials, such as marble and rusty iron, the RMSE of emissivity is below 0.05. The differences in the field of view angle and in the measuring direction between the Nicolet FTIR method and the method proposed in the paper, and the heterogeneity in the degree of oxidation, polishing and composition of the samples, are the main reasons for the differences of the emissivities between the two methods.
Zhang, Ren-Hua; Su, Hong-Bo; Tian, Jing; Mi, Su-Juan; Li, Zhao-Liang
2016-01-01
In the inversion of land surface temperature (LST) from satellite data, obtaining the information on land surface emissivity is most challenging. How to solve both the emissivity and the LST from the underdetermined equations for thermal infrared radiation is a hot research topic related to quantitative thermal infrared remote sensing. The academic research and practical applications based on the temperature-emissivity retrieval algorithms show that directly measuring the emissivity of objects at a fixed thermal infrared waveband is an important way to close the underdetermined equations for thermal infrared radiation. Based on the prior research results of both the authors and others, this paper proposes a new approach of obtaining the spectral emissivity of the object at 8–14 µm with a single-band CO2 laser at 10.6 µm and a 102F FTIR spectrometer. Through experiments, the spectral emissivity of several key samples, including aluminum plate, iron plate, copper plate, marble plate, rubber sheet, and paper board, at 8–14 µm is obtained, and the measured data are basically consistent with the hemispherical emissivity measurement by a Nicolet iS10 FTIR spectrometer for the same objects. For the rough surface of materials, such as marble and rusty iron, the RMSE of emissivity is below 0.05. The differences in the field of view angle and in the measuring direction between the Nicolet FTIR method and the method proposed in the paper, and the heterogeneity in the degree of oxidation, polishing and composition of the samples, are the main reasons for the differences of the emissivities between the two methods. PMID:27347964
Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-29
...., Steubenville, OH By applications dated May 15 and May 21, 2010, United Steel, Paper and Forestry, Rubber... back plate coils (TA-W-71,572A), hot rolled coils (TA- W-71,572B), and cold rolled coils (TA-W-71,572C...
Winners & Sinners: What's Hot and What's Not in Alumni Merchandising.
ERIC Educational Resources Information Center
Larson, Wendy Ann
1990-01-01
A large part of any merchandising program is picking products that will sell. Sixty alumni professionals were asked about their ideas. Some of the winners included a watch with the institution's seal, a windsock, and athletic shoes. Some of the losers included a sweater and a commemorative plate. (MLW)
NASA Technical Reports Server (NTRS)
1978-01-01
Progress in the development, fabrication, and delivery of solar subsystems consisting of a solar operated pump, and solar collectors which can be used in solar heating and cooling, or hot water, for single family, multifamily, or commercial applications is reported.
Development, testing, and certification of life sciences engineering solar collector
NASA Technical Reports Server (NTRS)
Caudle, J. M.
1978-01-01
Results are presented for the development of an air flat plate collector for use with solar heating, combined heating and cooling, and hot water systems. The contract was for final development, testing, and certification of the collector, and for delivery of a 320 square feet collector panel.
Solar hot water system installed at Days Inn Motel, Dallas, Texas (Forrest Lane)
NASA Technical Reports Server (NTRS)
1980-01-01
The solar system was designed to provide 65 percent of the total Domestic Hot Water (DHW) demand. The liquid flat plate (water) collector (1,000 square feet) system automatically drains into the 1,000 gallon steel storage tank located in the mechanical room when the pump is not running. Heat is transferred from the storage tank to DHW tanks through a tube and shell heat exchanger. A circulating pump between the DHW tanks and the heat exchanger enables solar heated water to help make DHW tank standby losses. All pumps are controlled by differential temperature.
Solar heating and hot water system installed at James Hurst Elementary School, Portsmouth, Virginia
NASA Technical Reports Server (NTRS)
1981-01-01
Solar heating and a hot water system installed in an elementary school in Portsmouth, Virginia are examined. The building is zoned into four heating/cooling areas. Each area is equipped with an air handling unit that is monitored and controlled by central control and monitoring system. The solar system for the building uses a collector area of 3,630 sq. ft. of flat plate liquid collectors, and a 6,000 gallon storage tank. System descriptions, maintenance reports, detailed component specifications, and design drawings to evaluate this solar system are reported.
NASA Astrophysics Data System (ADS)
1981-08-01
A solar space heating/domestic hot water system employing 150 square feet air flat plate collectors and 20,000 pounds of rock for storage is described. The collector, storage, energy to load, and auxiliary heat subsystems and five modes of operation are described. Auxiliary space heating is provided by an electric strip heater in the air ducts. The hot water system consists of an 80 gallon solar preheating tank which supplies a 40 gallon conventional tank. An electric heating element provides auxiliary heating in the preheat tank.
Solar heating and hot water system installed at Listerhill, Alabama
NASA Technical Reports Server (NTRS)
1978-01-01
The Solar system was installed into a new building and was designed to provide 79% of the estimated annual space heating load and 59% of the estimated annual potable hot water requirement. The collectors are flat plate, liquid manufactured by Reynolds Metals Company and cover a total area of 2344 square feet. The storage medium is water inhibited with NALCO 2755 and the container is an underground, unpressurized steel tank with a capacity of 5000 gallons. This report describes in considerable detail the solar heating facility and contains detailed drawings of the completed system.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1979-07-01
The objective of the work described in this volume was to conceptualize suitable designs for solar total energy systems for the following residential market segments: single-family detached homes, single-family attached units (townhouses), low-rise apartments, and high-rise apartments. Conceptual designs for the total energy systems are based on parabolic trough collectors in conjunction with a 100 kWe organic Rankine cycle heat engine or a flat-plate, water-cooled photovoltaic array. The ORC-based systems are designed to operate as either independent (stand alone) systems that burn fossil fuel for backup electricity or as systems that purchase electricity from a utility grid for electrical backup.more » The ORC designs are classified as (1) a high temperature system designed to operate at 600/sup 0/F and (2) a low temperature system designed to operate at 300/sup 0/F. The 600/sup 0/F ORC system that purchases grid electricity as backup utilizes the thermal tracking principle and the 300/sup 0/F ORC system tracks the combined thermal and electrical loads. Reject heat from the condenser supplies thermal energy for heating and cooling. All of the ORC systems utilize fossil fuel boilers to supply backup thermal energy to both the primary (electrical generating) cycle and the secondary (thermal) cycle. Space heating is supplied by a central hot water (hydronic) system and a central absorption chiller supplies the space cooling loads. A central hot water system supplies domestic hot water. The photovoltaic system uses a central electrical vapor compression air conditioning system for space cooling, with space heating and domestic hot water provided by reject heat from the water-cooled array. All of the systems incorporate low temperature thermal storage (based on water as the storage medium) and lead--acid battery storage for electricity; in addition, the 600/sup 0/F ORC system uses a therminol-rock high temperature storage for the primary cycle. (WHK)« less
NASA Astrophysics Data System (ADS)
Price, Allison A.; Jackson, Matthew G.; Blichert-Toft, Janne; Kurz, Mark D.; Gill, Jim; Blusztajn, Jerzy; Jenner, Frances; Brens, Raul; Arculus, Richard
2017-03-01
We present new Sr-Nd-Pb-Hf-He isotopic data for 65 volcanic samples from the northern Lau and North Fiji Basins. This includes 47 lavas obtained from 40 dredge sites spanning an east-west transect across the Lau and North Fiji basins, 10 ocean island basalt (OIB)-type lavas collected from seven Fijian islands, and eight OIB lavas sampled on Rotuma. For the first time, we are able to map clear north-south and east-west geochemical gradients in 87Sr/86Sr across the northern Lau and North Fiji Basins: lavas with the most geochemically enriched radiogenic isotopic signatures are located in the northeast Lau Basin, while signatures of geochemical enrichment are diminished to the south and west away from the Samoan hot spot. Based on these geochemical patterns and plate reconstructions of the region, these observations are best explained by the addition of Samoa, Rurutu, and Rarotonga hot spot material over the past 4 Ma. We suggest that underplated Samoan material has been advected into the Lau Basin over the past ˜4 Ma. As the slab migrated west (and toward the Samoan plume) via rollback over time, younger and hotter (and therefore less viscous) underplated Samoan plume material was entrained. Thus, entrainment efficiency of underplated plume material was enhanced, and Samoan plume signatures in the Lau Basin became stronger as the trench approached the Samoan hot spot. The addition of subducted volcanoes from the Cook-Austral Volcanic Lineament first from the Rarotonga hot spot, then followed by the Rurutu hot spot, contributes to the extreme geochemical signatures observed in the northeast Lau Basin.
NASA Astrophysics Data System (ADS)
Suter, C.; Jovanovic, Z.; Steinfeld, A.
2012-06-01
A thermoelectric stack composed of arrays of Bi-Te alloy thermoelectric converter (TEC) modules is considered for geothermal heat conversion. The TEC modules consist of Al2O3 plates with surface 30×30 mm2 and 127 p-type (Bi0.2Sb0.8)2Te3 and n-type Bi2(Te0.96Se0.04)3 thermoelement pairs, each having a cross-section of 1.05×1.05 mm2, and with a figure-of-merit of 1 and a heat-to-electricity conversion efficiency of ˜5%. A heat transfer model is formulated to couple conduction in the thermoelements with convection between the Al2O3 plates and the water flow in counter-flow channel configuration. The calculated open-circuit voltages are compared to those resulting from the mean temperature differences across the TEC modules computed by CFD. The investigated parameters are: hot water inlet and outlet temperatures (373 - 413 K and 323 - 363 K, respectively), stack length (300 - 1500 mm), thermoelement length (1 - 4 mm) and hot channel heights (0.2 - 2 mm). The heat transfer model is then applied to optimize a 1 kWel stack with hot water inlet at 393 K and outlet at 353 K for either maximum heat-to-electricity conversion efficiency of 2.9% or minimum size of 0.0044 m3.
NASA Technical Reports Server (NTRS)
Lin, E. I. H. (Inventor)
1984-01-01
A solar pond adapted for efficiently trapping and storing radiant solar energy without the use of a salt concentration gradient in the pond is disclosed. A body of water which may be fresh, saline, relatively clear or turbid, is substantially covered by a plurality of floating honeycomb panels. The honeycomb panels are made of a material such as glass which is pervious to short wave solar radiation but impervious to infrared radiation. Each honeycomb panel includes a multitude of honeycomb cells. The honeycomb panels are divided into the elongated honeycomb cells by a multitude of intermediate plates disposed between a bottom plate and top plate of the panel. The solar pond is well suited for providing hot water of approximately 85 to 90 C temperature for direct heating applications, and for electrical power generation.
Effect of LPSO and SFs on microstructure evolution and mechanical properties of Mg-Gd-Y-Zn-Zr alloy
NASA Astrophysics Data System (ADS)
Xu, Chao; Nakata, Taiki; Qiao, Xiaoguang; Zheng, Mingyi; Wu, Kun; Kamado, Shigeharu
2017-01-01
High performance Mg-8.2Gd-3.8Y-1.0Zn-0.4Zr alloy with high strength and excellent ductility has been successfully developed by hot extrusion. The effect of plate-shaped long period stacking ordered (LPSO) phases and solute-segregated stacking faults (SFs) on the dynamically recrystallization (DRX) behavior was analyzed. The plate-shaped LPSO phases stimulate the DRX by particle stimulated nucleation mechanism, leading to higher DRX ratio and weaker basal texture. While for the alloy with dense fine SFs inside the original grains, discontinuous DRX initially occurs at the original grain boundaries, and the DRX is obviously restricted. Consequently, alloy containing dense SFs exhibits higher strength but lower ductility compared with alloy with plated-shaped LPSO phases.
Effect of LPSO and SFs on microstructure evolution and mechanical properties of Mg-Gd-Y-Zn-Zr alloy
Xu, Chao; Nakata, Taiki; Qiao, Xiaoguang; Zheng, Mingyi; Wu, Kun; Kamado, Shigeharu
2017-01-01
High performance Mg-8.2Gd-3.8Y-1.0Zn-0.4Zr alloy with high strength and excellent ductility has been successfully developed by hot extrusion. The effect of plate-shaped long period stacking ordered (LPSO) phases and solute-segregated stacking faults (SFs) on the dynamically recrystallization (DRX) behavior was analyzed. The plate-shaped LPSO phases stimulate the DRX by particle stimulated nucleation mechanism, leading to higher DRX ratio and weaker basal texture. While for the alloy with dense fine SFs inside the original grains, discontinuous DRX initially occurs at the original grain boundaries, and the DRX is obviously restricted. Consequently, alloy containing dense SFs exhibits higher strength but lower ductility compared with alloy with plated-shaped LPSO phases. PMID:28134297
High temperature thermocouple and heat flux gauge using a unique thin film-hardware hot juncture
NASA Technical Reports Server (NTRS)
Liebert, C. H.; Holanda, R.; Hippensteele, S. A.; Andracchio, C. A.
1984-01-01
A special thin film-hardware material thermocouple (TC) and heat flux gauge concept for a reasonably high temperature and high flux flat plate heat transfer experiment was fabricated and tested to gauge temperatures of 911 K. This concept was developed for minimal disturbance of boundary layer temperature and flow over the plates and minimal disturbance of heat flux through the plates. Comparison of special heat flux gauge Stanton number output at steady-state conditions with benchmark literature data was good and agreement was within a calculated uncertainty of the measurement system. Also, good agreement of special TC and standard TC outputs was obtained and the results are encouraging. Oxidation of thin film thermoelements was a primary failure mode after about 5 of operation.
Cascade Mountain Range in Oregon
Sherrod, David R.
2016-01-01
Along its Oregon segment, the Cascade Range is almost entirely volcanic in origin. The volcanoes and their eroded remnants are the visible magmatic expression of the Cascadia subduction zone, where the offshore Juan de Fuca tectonic plate is subducted beneath North America. Subduction occurs as two lithospheric plates collide, and an underthrusted oceanic plate is commonly dragged into the mantle by the pull of gravity, carrying ocean-bottom rock and sediment down to where heat and pressure expel water. As this water rises, it lowers the melting temperature in the overlying hot mantle rocks, thereby promoting melting. The molten rock supplies the volcanic arcs with heat and magma. Cascade Range volcanoes are part of the Ring of Fire, a popular term for the numerous volcanic arcs that encircle the Pacific Ocean.
Aerodynamic Leidenfrost effect
NASA Astrophysics Data System (ADS)
Gauthier, Anaïs; Bird, James C.; Clanet, Christophe; Quéré, David
2016-12-01
When deposited on a plate moving quickly enough, any liquid can levitate as it does when it is volatile on a very hot solid (Leidenfrost effect). In the aerodynamic Leidenfrost situation, air gets inserted between the liquid and the moving solid, a situation that we analyze. We observe two types of entrainment. (i) The thickness of the air gap is found to increase with the plate speed, which is interpreted in the Landau-Levich-Derjaguin frame: Air is dynamically dragged along the surface and its thickness results from a balance between capillary and viscous effects. (ii) Air set in motion by the plate exerts a force on the levitating liquid. We discuss the magnitude of this aerodynamic force and show that it can be exploited to control the liquid and even to drive it against gravity.
High-temperature thermocouple and heat flux gauge using a unique thin film-hardware hot junction
NASA Technical Reports Server (NTRS)
Liebert, C. H.; Holanda, R.; Hippensteele, S. A.; Andracchio, C. A.
1985-01-01
A special thin film-hardware material thermocouple (TC) and heat flux gauge concept for a reasonably high temperature and high flux flat plate heat transfer experiment was fabricated and tested to gauge temperatures of 911 K. This concept was developed for minimal disturbance of boundary layer temperature and flow over the plates and minimal disturbance of heat flux through the plates. Comparison of special heat flux gauge Stanton number output at steady-state conditions with benchmark literature data was good and agreement was within a calculated uncertainty of the measurement system. Also, good agreement of special TC and standard TC outputs was obtained and the results are encouraging. Oxidation of thin film thermoelements was a primary failure mode after about 5 of operation.
NASA Astrophysics Data System (ADS)
van Thienen, P.; Vlaar, N. J.; van den Berg, A. P.
2005-06-01
Geophysical arguments against plate tectonics in a hotter Earth, based on buoyancy considerations, require an alternative means of cooling the planet from its original hot state to the present situation. Such an alternative could be extensive flood volcanism in a more stagnant-lid like setting. Starting from the notion that all heat output of the Earth is through its surface, we have constructed two parametric models to evaluate the cooling characteristics of these two mechanisms: plate tectonics and basalt extrusion/flood volcanism. Our model results show that for a steadily (exponentially) cooling Earth, plate tectonics is capable of removing all the required heat at a rate of operation comparable to or even lower than its current rate of operation, contrary to earlier speculations. The extrusion mechanism may have been an important cooling agent in the early Earth, but requires global eruption rates two orders of magnitude greater than those of known Phanerozoic flood basalt provinces. This may not be a problem, since geological observations indicate that flood volcanism was both stronger and more ubiquitous in the early Earth. Because of its smaller size, Mars is capable of cooling conductively through its lithosphere at significant rates, and as a result may have cooled without an additional cooling mechanism. Venus, on the other hand, has required the operation of an additional cooling agent for probably every cooling phase of its possibly episodic history, with rates of activity comparable to those of the Earth.
Economic analysis of solar assisted absorption chiller for a commercial building
NASA Astrophysics Data System (ADS)
Antonyraj, Gnananesan
Dwindling fossil fuels coupled with changes in global climate intensified the drive to make use of renewable energy resources that have negligible impact on the environment. In this attempt, the industrial community produced various devices and systems to make use of solar energy for heating and cooling of building space as well as generate electric power. The most common components employed for collection of solar energy are the flat plate and evacuated tube collectors that produce hot water that can be employed for heating the building space. In order to cool the building, the absorption chiller is commonly employed that requires hot water at high temperatures for its operation. This thesis deals with economic analysis of solar collector and absorption cooling system to meet the building loads of a commercial building located in Chattanooga, Tennessee. Computer simulations are employed to predict the hourly building loads and performance of the flat plate and evacuated tube solar collectors using the hourly weather data. The key variables affecting the economic evaluation of such system are identified and the influence of these parameters is presented. The results of this investigation show that the flat plate solar collectors yield lower payback period compared to the evacuated tube collectors and economic incentives offered by the local and federal agencies play a major role in lowering the payback period.
Earth's oldest stable crust in the Pilbara Craton formed by cyclic gravitational overturns
NASA Astrophysics Data System (ADS)
Wiemer, Daniel; Schrank, Christoph E.; Murphy, David T.; Wenham, Lana; Allen, Charlotte M.
2018-05-01
During the early Archaean, the Earth was too hot to sustain rigid lithospheric plates subject to Wilson Cycle-style plate tectonics. Yet by that time, up to 50% of the present-day continental crust was generated. Preserved continental fragments from the early Archaean have distinct granite-dome/greenstone-keel crust that is interpreted to be the result of a gravitationally unstable stratification of felsic proto-crust overlain by denser mafic volcanic rocks, subject to reorganization by Rayleigh-Taylor flow. Here we provide age constraints on the duration of gravitational overturn in the East Pilbara Terrane. Our U-Pb ages indicate the emplacement of 3,600-3,460-million-year-old granitoid rocks, and their uplift during an overturn event ceasing about 3,413 million years ago. Exhumation and erosion of this felsic proto-crust accompanied crustal reorganization. Petrology and thermodynamic modelling suggest that the early felsic magmas were derived from the base of thick ( 43 km) basaltic proto-crust. Combining our data with regional geochronological studies unveils characteristic growth cycles on the order of 100 million years. We propose that maturation of the early crust over three of these cycles was required before a stable, differentiated continent emerged with sufficient rigidity for plate-like behaviour.
NASA Astrophysics Data System (ADS)
Janaun, J.; Kamin, N. H.; Wong, K. H.; Tham, H. J.; Kong, V. V.; Farajpourlar, M.
2016-06-01
Air heating unit is one of the most important parts in paddy drying to ensure the efficiency of a drying process. In addition, an optimized air heating unit does not only promise a good paddy quality, but also save more for the operating cost. This study determined the suitable and best specifications heating unit to heat air for paddy drying in the LAMB dryer. In this study, Aspen HYSYS v7.3 was used to obtain the minimum flow rate of hot water needed. The resulting data obtained from Aspen HYSYS v7.3 were used in Aspen Exchanger Design and Rating (EDR) to generate heat exchanger design and costs. The designs include shell and tubes and plate heat exchanger. The heat exchanger was designed in order to produce various drying temperatures of 40, 50, 60 and 70°C of air with different flow rate, 300, 2500 and 5000 LPM. The optimum condition for the heat exchanger were found to be plate heat exchanger with 0.6 mm plate thickness, 198.75 mm plate width, 554.8 mm plate length and 11 numbers of plates operating at 5000 LPM air flow rate.
Resolving hot spot microstructure using x-ray penumbral imaging (invited)
NASA Astrophysics Data System (ADS)
Bachmann, B.; Hilsabeck, T.; Field, J.; Masters, N.; Reed, C.; Pardini, T.; Rygg, J. R.; Alexander, N.; Benedetti, L. R.; Döppner, T.; Forsman, A.; Izumi, N.; LePape, S.; Ma, T.; MacPhee, A. G.; Nagel, S.; Patel, P.; Spears, B.; Landen, O. L.
2016-11-01
We have developed and fielded x-ray penumbral imaging on the National Ignition Facility in order to enable sub-10 μm resolution imaging of stagnated plasma cores (hot spots) of spherically shock compressed spheres and shell implosion targets. By utilizing circular tungsten and tantalum apertures with diameters ranging from 20 μm to 2 mm, in combination with image plate and gated x-ray detectors as well as imaging magnifications ranging from 4 to 64, we have demonstrated high-resolution imaging of hot spot plasmas at x-ray energies above 5 keV. Here we give an overview of the experimental design criteria involved and demonstrate the most relevant influences on the reconstruction of x-ray penumbral images, as well as mitigation strategies of image degrading effects like over-exposed pixels, artifacts, and photon limited source emission. We describe experimental results showing the advantages of x-ray penumbral imaging over conventional Fraunhofer and photon limited pinhole imaging and showcase how internal hot spot microstructures can be resolved.
Resolving hot spot microstructure using x-ray penumbral imaging (invited).
Bachmann, B; Hilsabeck, T; Field, J; Masters, N; Reed, C; Pardini, T; Rygg, J R; Alexander, N; Benedetti, L R; Döppner, T; Forsman, A; Izumi, N; LePape, S; Ma, T; MacPhee, A G; Nagel, S; Patel, P; Spears, B; Landen, O L
2016-11-01
We have developed and fielded x-ray penumbral imaging on the National Ignition Facility in order to enable sub-10 μm resolution imaging of stagnated plasma cores (hot spots) of spherically shock compressed spheres and shell implosion targets. By utilizing circular tungsten and tantalum apertures with diameters ranging from 20 μm to 2 mm, in combination with image plate and gated x-ray detectors as well as imaging magnifications ranging from 4 to 64, we have demonstrated high-resolution imaging of hot spot plasmas at x-ray energies above 5 keV. Here we give an overview of the experimental design criteria involved and demonstrate the most relevant influences on the reconstruction of x-ray penumbral images, as well as mitigation strategies of image degrading effects like over-exposed pixels, artifacts, and photon limited source emission. We describe experimental results showing the advantages of x-ray penumbral imaging over conventional Fraunhofer and photon limited pinhole imaging and showcase how internal hot spot microstructures can be resolved.
Development of an innovative solar absorber
NASA Astrophysics Data System (ADS)
Goodchild, Gavin
Solar thermal systems have great potential to replace or reduce the dependence of conventional fossil fuel based heating technologies required for space and water heating. Specifically solar domestic hot water systems can contribute 50-75% of the annual thermal load. To date residential users have been slow to purchase and install systems, primarily due to the large monetary investment required to purchase and install a system. Recent innovations in materials design and manufacturing techniques, offer opportunities for the development of absorber plate designs that have the potential to reduce cost, increase efficiency and reduce payback periods. Consequently, this design study was conducted in conjunction with industrial partners to develop an improved absorber based on roll bond manufacturing that can be produced at reduced cost with comparable or greater thermal efficiency.
Vacuum vapor deposition gun assembly
Zeren, Joseph D.
1985-01-01
A vapor deposition gun assembly includes a hollow body having a cylindrical outer surface and an end plate for holding an adjustable heat sink, a hot hollow cathode gun, two magnets for steering the plasma from the gun into a crucible on the heat sink, and a shutter for selectively covering and uncovering the crucible.
A DNA Melting Exercise for a Large Laboratory Class
ERIC Educational Resources Information Center
Levine, Lauren A.; Junker, Matthew; Stark, Myranda; Greenleaf, Dustin
2015-01-01
A simple and economical experimental setup is described that enables multiple individuals or groups within a laboratory class to measure the thermal melting of double stranded DNA simultaneously. The setup utilizes a basic spectrophotometer capable of measuring absorbance at 260 nm, UV plastic cuvettes, and a stirring hot plate. Students measure…
46 CFR 63.25-3 - Electric hot water supply boilers.
Code of Federal Regulations, 2011 CFR
2011-10-01
... elements must be secured in a manner which prevents loosening. (e) Iron and steel parts must be protected against corrosion by enameling, galvanizing, or plating. Iron and steel storage tanks having a wall thickness less than 6.4mm (1/4-inch) must have the inside surface protected against corrosion. (f) Each...
It's Hard Saying Goodbye to an Old Flame
ERIC Educational Resources Information Center
Roy, Ken
2004-01-01
As heat sources go, the old standby for elementary and middle school science laboratories has been the centuries old alcohol lamp. Unfortunately, this inexpensive heat producer has been a continuous source of accidents--many of which are relatively serious. Hot plates are emerging as the most popular source of heat for science experiments. The…
Condensation of acetol and acetic acid vapor with sprayed liquid
USDA-ARS?s Scientific Manuscript database
A cellulose-derived fraction of biomass pyrolysis vapor was simulated by evaporating acetol and acetic acid (AA) from flasks on a hot plate. The liquid in the flasks was infused with heated nitrogen. The vapor/nitrogen stream was superheated in a tube oven and condensed by contact with a cloud of ...
Liu, L; Li, G; Zhu, F; Wang, L; Wang, Y
1990-11-01
Hot plate and writhing methods were used in the comparison of the analgesic effect of vinegar-processed fresh tuber corydalis and the traditionally vinegar-processed Rhizoma Corydalis. The result shows that the effect of the former is stronger than that of the latter.
LARGO hot water system thermal performance test report
NASA Technical Reports Server (NTRS)
1978-01-01
The thermal performance tests and results on the LARGO Solar Hot Water System under natural environmental conditions is presented. Some objectives of these evaluations are to determine the amount of energy collected, the amount of energy delivered to the household as contributed by solar power supplied to operate the system and auxiliary power to maintain tank temperature at proper level, overall system efficiency and to determine temperature distribution within the tank. The Solar Hot Water system is termed a Dump-type because of the draining system for freeze protection. The solar collector is a single glazed flat plate. An 82-gallon domestic water heater is provided as the energy storage vessel. Water is circulated through the collector and water heater by a 5.3 GPM capacity pump, and control of the pump motor is achieved by a differential temperature controller.
Spontaneous jumping, bouncing and trampolining of hydrogel drops on a heated plate.
Pham, Jonathan T; Paven, Maxime; Wooh, Sanghyuk; Kajiya, Tadashi; Butt, Hans-Jürgen; Vollmer, Doris
2017-10-13
The contact between liquid drops and hot solid surfaces is of practical importance for industrial processes, such as thermal spraying and spray cooling. The contact and bouncing of solid spheres is also an important event encountered in ball milling, powder processing, and everyday activities, such as ball sports. Using high speed video microscopy, we demonstrate that hydrogel drops, initially at rest on a surface, spontaneously jump upon rapid heating and continue to bounce with increasing amplitudes. Jumping is governed by the surface wettability, surface temperature, hydrogel elasticity, and adhesion. A combination of low-adhesion impact behavior and fast water vapor formation supports continuous bouncing and trampolining. Our results illustrate how the interplay between solid and liquid characteristics of hydrogels results in intriguing dynamics, as reflected by spontaneous jumping, bouncing, trampolining, and extremely short contact times.Drops of liquid on a hot surface can exhibit fascinating behaviour such as the Leidenfrost effect in which drops hover on a vapour layer. Here Pham et al. show that when hydrogel drops are placed on a rapidly heated plate they bounce to increasing heights even if they were initially at rest.
Synthesis and Evaluation of New 1,3,4-Thiadiazole Derivatives as Antinociceptive Agents.
Altıntop, Mehlika Dilek; Can, Özgür Devrim; Demir Özkay, Ümide; Kaplancıklı, Zafer Asım
2016-08-01
In the current work, new 1,3,4-thiadiazole derivatives were synthesized and investigated for their antinociceptive effects on nociceptive pathways of nervous system. The effects of these compounds against mechanical, thermal and chemical stimuli were evaluated by tail-clip, hot-plate and acetic acid-induced writhing tests, respectively. In addition, activity cage was performed to assess the locomotor activity of animals. The obtained data indicated that compounds 3b, 3c, 3d, 3e, 3g and 3h increased the reaction times of mice both in the hot-plate and tail-clip tests, indicating the centrally mediated antinociceptive activity of these compounds. Additionally, the number of writhing behavior was significantly decreased by the administration of compounds 3a, 3c, 3e and 3f, which pointed out the peripherally mediated antinociceptive activity induced by these four compounds. According to the activity cage tests, compounds 3a, 3c and 3f significantly decreased both horizontal and vertical locomotor activity of mice. Antinociceptive behavior of these three compounds may be non-specific and caused by possible sedative effect or motor impairments.
NASA Astrophysics Data System (ADS)
Zhu, Yuanzhi; Wang, Shizhi; Yang, Qingda; Zhou, Feng
2014-09-01
Two twin roll casts (TRCs) and one hot rolled (HR) AA 1235 aluminum alloy plates with different microstructures are prepared. The plates were electrolyzed in a 1.2 wt% HCl solution with a voltage of 21 V and a current of 1.9 mA. The shape, size, and number of pores formed on the surfaces of these plates were analyzed and correlated with the microstructures of the plates. It is found that pores are easier to form on the alloy plates containing subgrains with a lower dislocation density inside the subgrains, rather than along the grain boundaries. Furthermore, Fe- and Si-enriched particles in the AA1235 aluminum alloys lead to the formation of pores on the surface during electrolyzing; the average precipitate sizes of 4, 3.5, and 2 μm in Alloy 1#, Alloy 2# and Alloy 3# result in the average pore sizes of 3.78, 2.76, and 1.9 μm on the surfaces of the three alloys, respectively; The G.P zone in the alloy also facilitates the surface pore formation. High-surface roughness enhances the possibility of entrapping more lubricants into the plate surface, which eventually blocks the formation of the pores on the surface of the aluminum plates in the following electrolyzing process.
Plume-induced subduction and accretion on present-day Venus and Archean Earth
NASA Astrophysics Data System (ADS)
Davaille, A.; Smrekar, S. E.; Sibrant, A.; Mittelstaedt, E. L.
2017-12-01
Plate tectonics is responsible for the majority of Earth's heat loss, cycling of volatiles between the atmosphere and interior, recycling in the mantle of most of the surface plates, and possibly even for maintaining habitability. Despite its similarity in size and bulk density to Earth, Venus lacks plate tectonics today, and its mode of operation remains debated. Using laboratory experiments in colloidal dispersion which brittle viscosity-elasto-plastic rheology, we recently showed that plume-induced subduction could be operating nowadays on Venus. The experimental fluids were heated from below to produce upwelling plumes, which in turn produced tensile fractures in the lithosphere-like skin that formed on the upper surface. Plume material upwelling through the fractures then spread above the skin, analogous to volcanic flooding, and lead to bending and eventual subduction of the skin along arcuate segments. These segments are analogous to the semi-circular trenches seen on large coronae. Scaling analysis suggests that this regime with limited, plume-induced subduction is favored by a hot lithosphere, such as that found on early Earth or present-day Venus. Moreover, in this regime, subduction proceeds primarily by roll-back and the coronae expands through time at velocity that could reach 10 cm/yr. A second set of experiments focusing on accretion processes suggests that accretion dynamics depends on the strength of the lithosphere, as well as the spreading velocity. Venus hot surface temperature would act to decrease the lithosphere strength, and therefore weaken the ridge axis, that would become highly unstable, showing large sinuosity and producing a number of micro-plates. These plume, subduction, and accretion characteristics explain well the features seen in Artemis coronae, the largest coronae on Venus.
The contemporary North Pangea supercontinent and the geodynamic causes of its formation
NASA Astrophysics Data System (ADS)
Kovalenko, V. I.; Yarmolyuk, V. V.; Bogatikov, O. A.
2010-11-01
The supercontinental status of the contemporary aggregation of continents called North Pangea is substantiated. This supercontinent comprises all continents with the probable exception of Antarctica. In addition to the spatial contiguity of continents, the supercontinent is characterized by the prevalence of the continental crust that combines North America and Eurasia, Eurasia and Africa, and Eurasia and Australia. Over the course of the 300-250-Ma evolution from Wegener's Pangea to contemporary North Pangea, the aggregation of continents has not lost its supercontinental status, despite modification of the supercontinent shape and opening and closure of the newly formed Paleotethys, Tethys, Atlantic, and Indian oceans. Over the last 250-300 Ma, all movements of the lithospheric plates have most likely occurred within the Indo-Atlantic segment of the Earth, whereas the Pacific segment has remained oceanic. In short, the formation of the North Pangea supercontinent can be outlined in the following terms. The long and deep subduction of the lithospheric plates beneath Eurasia and North America gave rise to the stabilization of the continents and accumulation of huge bodies of the cold lithosphere commensurable in volume with the upper mantle at the deeper mantle levels. This brought about compensation ascent of hot mantle (mantle plumes) near the convergent plate boundaries and far from them. A special geodynamic setting develops beneath the supercontinent. Due to encircling subduction of the lithospheric plates and related squeezing of the hot mantle, an ascending flow, or plume (superplume) formed beneath the central part of the supercontinent. In our view, the African superplume broke up Wegener's Pangea in the Atlantic region, caused the opening of the Atlantic and Indian oceans, and migrated to the Arctic Region 53 Ma ago.
DOE Office of Scientific and Technical Information (OSTI.GOV)
D. M. Perez
2011-05-01
The RERTR-9 experiment was designed to test the effect of modified fuel/clad interfaces in monolithic fuel plates and to demonstrate that the addition of Si to the matrix material in dispersion plates continued to be effective at high loading (~8.5 g U/cc). Several monolithic fuel plates were fabricated by Hot Isostatic Pressing (HIP) and Friction Bonding (FB) with thin layers of Si inserted and by HIP with a Zr diffusion barrier between the fuel and cladding. Si was applied to the interface by thermal spray of Al Si mixtures and by the insertion of thin Si-rich Al alloy foil betweenmore » the fuel/clad interface. The dispersion fuel plates were fabricated by semi-standard rolling techniques (the reduction by rolling was lowered to limit fabrication defects). Matrix materials consisted of Al-Si alloys and mixtures with various levels of Si. The following report summarizes the life of the RERTR-9A/B experiment through end of irradiation, including as-run neutronic analysis, thermal analysis and hydraulic testing results.« less
Brown, Donald William; Okuniewski, Maria A.; Sisneros, Thomas A.; ...
2016-12-01
Here, Al clad U-10Mo fuel plates are being considered for conversion of several research reactors from high-enriched to low-enriched U fuel. Neutron diffraction measurements of the textures, residual phase stresses, and dislocation densities in the individual phases of the mini-foils throughout several processing steps and following hot-isostatic pressing to the Al cladding, have been completed. Recovery and recrystallization of the bare U-10Mo fuel foil, as indicated by the dislocation density and texture, are observed depending on the state of the material prior to annealing and the duration and temperature of the annealing process. In general, the cladding procedure significantly reducesmore » the dislocation density, but the final state of the clad plate, both texture and dislocation density, depends strongly on the final processing step of the fuel foil. In contrast, the residual stress state of the final plate is dominated by the thermal expansion mismatch of the constituent materials.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brown, Donald William; Okuniewski, Maria A.; Sisneros, Thomas A.
Here, Al clad U-10Mo fuel plates are being considered for conversion of several research reactors from high-enriched to low-enriched U fuel. Neutron diffraction measurements of the textures, residual phase stresses, and dislocation densities in the individual phases of the mini-foils throughout several processing steps and following hot-isostatic pressing to the Al cladding, have been completed. Recovery and recrystallization of the bare U-10Mo fuel foil, as indicated by the dislocation density and texture, are observed depending on the state of the material prior to annealing and the duration and temperature of the annealing process. In general, the cladding procedure significantly reducesmore » the dislocation density, but the final state of the clad plate, both texture and dislocation density, depends strongly on the final processing step of the fuel foil. In contrast, the residual stress state of the final plate is dominated by the thermal expansion mismatch of the constituent materials.« less
Wet Tectonics: A New Planetary Synthesis
NASA Astrophysics Data System (ADS)
Grimm, K. A.
2005-12-01
Most geoscientists (and geoscience textbooks) describe plate tectonics as a `solid-Earth' phenomenon, with fluids playing an important role in discrete geodynamic processes. As a community of diverse research specialists, the critical role of water is being widely elucidated, however these diverse studies do not address the fundamental origin and operation of the global plate tectonic phenomenon, and its expressions in planetary geodynamics and geomorphology. The Wet Tectonics hypothesis extends well beyond the plate tectonics paradigm, to constitute a new synthesis of diverse geoscience specializations and self-organizing complexity into a simple, internally consistent and explicitly testable model. The Wet Tectonics hypothesis asserts that Earth's plate tectonic system arose from and is the explicit and dynamic result of water interacting with the hot silicate mantle. The tectosphere is defined as an interactive functional (rather than structural, compositional or rheological) entity, a planetary-scale dynamic system of plate formation, plate motion, and rock/volatile recycling. Earth's tectosphere extends from the base of the asthenosphere to the top of the crust, arising and evolving as a dynamic pattern of organization that creates, orders and perpetuates itself. Earth's tectosphere is energetically-open, materially ajar (steady-state operation may not require sub-asthenospheric inputs; shifts between distinct tectonic modes may result from changes in coupling between the tectosphere and subasthenospheric reservoirs) and chemically-closed (i.e. the tectosphere recycles its own wastes). Water is a fundamental requirement in all of the constituent processes of Earth's tectosphere, including seafloor spreading, slab cooling/subsidence, plate motion, asthenosphere rheology, and subduction (where crustal and volatile recycling occur). As a working hypothesis, we suggest that the dynamic and persistent hydrosphere and tectosphere on planet Earth are fully interdependent and co-evolving phenomena. The concept of autocatalytic hypercycles has been adapted from molecular biology to resolve the apparent paradox of circular causality amongst the coupled phenomena of liquid water oceans and `plate tectonics'. This new planetary synthesis presents fundamental implications for geological, geophysical, Earth system and planetary sciences, as well as novel hypotheses concerning plate drive (gravity sliding ± slab pull), origin of plate tectonics (Hadean, >=4.4Ga), biogeochemical cycling (balanced global fluxes of water into and out of the tectosphere; is the asthenosphere continuously rehydrated via lateral advection) and planetary geomorphology (simple contrasts between Mars, Earth and Venus).
Role of muscarinic receptor subtypes in central antinociception.
Bartolini, A.; Ghelardini, C.; Fantetti, L.; Malcangio, M.; Malmberg-Aiello, P.; Giotti, A.
1992-01-01
1. The ability to modify the pain threshold by the two M1-muscarinic agonists: McN-A-343 and AF-102B and by the specific M2-agonist arecaidine was examined in mice and rats by using three different noxious stimuli: chemical (writhing test), thermic (hot-plate test) and mechanical (paw pressure test). 2. In the mouse hot-plate test McN-A-343 (20-50 micrograms per mouse i.c.v.) and AF-102B (1-10 mg kg-1 i.p.) produced significant antinociception which was prevented by atropine (1 microgram per mouse i.c.v.) and by the two selective M1 antagonists: pirenzepine (0.01 micrograms per mouse i.c.v.) and dicyclomine (0.08 micrograms per mouse i.c.v. or 10 mg kg-1 i.p.) but not by the specific M2-antagonist AFDX-116 (0.1 micrograms per mouse i.c.v.), naloxone (1 mg kg-1 i.p.) or by the acetylcholine (ACh) depletor hemicholinium-3 (HC-3) (1 micrograms per mouse i.c.v.). McN-A-343 and AF-102B were able to increase the pain threshold also in the mouse acetic acid writhing test and in rat paw pressure test. These antinociceptive effects were completely prevented by dicyclomine (0.08 micrograms per mouse i.c.v. or 10 mg kg-1 i.p.) but not by AFDX-116 (0.1 microgram per mouse or rat i.c.v.). 3. In contrast with the M1-agonists, the M2-agonist arecaidine (0.1-2 micrograms per mouse or rat i.c.v.) did not induce antinociception in all three analgesic tests. However, arecaidine, at the same i.c.v. doses, was able to reduce the pain threshold in the hot-plate and paw pressure tests.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1375858
Analgesic, antioedematous and antioxidant activity of γ-butyrolactone derivatives in rodents.
Salat, Kinga; Librowski, Tadeusz; Moniczewski, Andrzej; Stanisz-Wallis, Krystyna; Wieckowski, Krzysztof; Malawska, Barbara
2012-08-01
In this paper, the analgesic, antioedematous, motor-impairing and antioxidant properties of four γ-butyrolactone derivatives (BM113, BM113A, BM138 and BM138A) are described. Pain was induced by thermal (hot-plate test), chemical (writhing test) or mechanical (Randall-Selitto model) stimulation. All in-vivo assays were carried out in mice pretreated intraperitoneally with the test compounds, except for the evaluation of anti-inflammatory and analgesic activities in the carrageenan-induced paw oedema model, in which rats were pretreated orally with these compounds. In the hot-plate assay, BM113A and BM138A dose dependently prolonged the latency of the nociceptive reaction. Their analgesic activity, measured as a median effective dose (ED(50)=4.7 mg/kg), was similar to that of morphine (2.4 mg/kg). In the writhing test, all four compounds, in particular BM113A and BM138A, showed higher potency than the reference drug acetylsalicylic acid (the ED(50) values were 3.7, 2.3 and 46.1 mg/kg, respectively). BM138 caused a dose-dependent diminution of paw oedema (up to 49%) in the carrageenan model and BM138A at 200 mg/kg reduced mechanical hyperalgesia in the Randall-Selitto test (∼30% when compared with the control). None of the γ-butyrolactone derivatives tested at the ED(50) obtained in the hot-plate test influenced the locomotor activity of mice, although in the rotarod test at 24 rpm, BM113A and BM138 at 100 mg/kg showed some motor-impairing properties. In vitro, a concentration-dependent ABTS radical cation-scavenging activity of BM138 and BM138A (up to 80% inhibition of the radical absorbance) was observed. The results of the present study suggest that BM138 and BM138A could be of interest for future investigations as antinociceptive and antioedematous agents with potential free radical-scavenging properties.
Ocean Island Volcanoes—Just How Similar Are They?
NASA Astrophysics Data System (ADS)
Poland, M. P.; Peltier, A.; Bonforte, A.; Puglisi, G.
2016-12-01
Basaltic ocean island volcanoes are exceptional natural laboratories for volcanology. They present a range of eruptive styles, unrest and eruptions are frequent, and good accessibility facilitates detailed observation. The most important factors controlling the style and composition of volcanism at ocean islands are the tectonic setting and magma supply. Hawaíi represents an end member in this respect, located in the middle of an old and rapidly moving plate and with the highest magma supply of any ocean island hot spot. Hawaiian volcanoes are thus large, prone to collapse, and have a compositional evolution that reflects varying degrees of partial melt as they pass over the source hot spot. The Galápagos, in contrast, fall at the other end of the spectrum in most respects—the islands are on a young plate near a spreading center and have comparatively low magma supply. Collapse of Galápagos volcanoes is not common, the edifices are much smaller than their Hawaiian counterparts, and compositional evolution is spatially variable due to thin lithosphere and interaction between hot spot and mid-ocean ridge melts. La Réunion is something of a mix between these extremes, being located in the middle of an old but slow-moving plate and with a low magma supply. The resulting volcanoes have a straightforward compositional evolution, are relatively small in size but long-lived, and have unstable flanks. The broad context of magma supply and tectonic setting provides a useful means of interpreting the characteristics of ocean island volcanism. Gross similarities in volcano morphology (shield structure) and eruptive activity (effusive lava flows) create a perception that these volcanoes are analogs for one another. While it is certainly true that insights from Kīlauea have potential application at Piton de la Fournaise, for example, such lessons should not be applied without a good understanding of the substantial differences between volcanoes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Joshi, Vineet V.; Paxton, Dean M.; Lavender, Curt A.
Over the past several years Pacific Northwest National Laboratory (PNNL) has been actively involved in supporting the U.S. Department of Energy National Nuclear Security Administration Office of Material Management and Minimization (formerly Global Threat Reduction Initiative). The U.S. High- Power Research Reactor (USHPRR) project is developing alternatives to existing highly enriched uranium alloy fuel to reduce the proliferation threat. One option for a high-density metal fuel is uranium alloyed with 10 wt% molybdenum (U-10Mo). Forming the U-10Mo fuel plates/foils via rolling is an effective technique and is actively being pursued as part of the baseline manufacturing process. The processing ofmore » these fuel plates requires systematic investigation/understanding of the pre- and post-rolling microstructure, end-state mechanical properties, residual stresses, and defects, their effect on the mill during processing, and eventually, their in-reactor performance. In the work documented herein, studies were conducted to determine the effect of cold and hot rolling the as-cast and homogenized U-10Mo on its microstructure and hardness. The samples were homogenized at 900°C for 48 h, then later annealed for several durations and temperatures to investigate the effect on the material’s microstructure and hardness. The rolling of the as-cast plate, both hot and cold, was observed to form a molybdenum-rich and -lean banded structure. The cold rolling was ineffective, and in some cases exacerbated the as-cast defects. The grains elongated along the rolling direction and formed a pancake shape, while the carbides fractured perpendicularly to the rolling direction and left porosity between fractured particles of UC. The subsequent annealing of these samples at sub-eutectoid temperatures led to rapid precipitation of the ' lamellar phase, mainly in the molybdenum-lean regions. Annealing the samples above the eutectoid temperature did not refine the grain size or the banded microstructure. However, annealing the samples led to quick recovery in hardness as evidenced by a drop in Vickers hardness of 20%. Hot rolling was performed at 650 and 800°C. The hot-rolling mill loads (load separation force) were approximately 40 to 50% less than the cold-rolling for the same reduction and thickness. It was observed that hot rolling the samples with 50% or more reduction in thickness were responsible for dynamic recrystallization in the hot-rolled samples and led to grain refinement. Unlike the cold-rolled samples, the hot-rolled samples did not fracture the carbides and appeared to heal the casting defects. The recovery phenomenon was similar to the cold-rolled samples above the eutectoid temperatures, but owing to the refined grain size, the precipitation of the lamellar phase was far more rapid in these samples and the hardness increased more rapidly than in the cold rolled sample when heated below the eutectoid temperature. The data generated from these rolling efforts has been used to make the process modeling efforts more robust and applicable to all USHPRR partner rolling mills. The flow stress for cold rolling the samples was determined to be between 170-190 ksi, with frictional forces between 0.2 and 0.4 for the PNNL mill. The measured roll separation forces and those simulated using finite element methods for hot and cold rolling for the PNNL rolling mill were in good agreement.« less
NASA Astrophysics Data System (ADS)
Elagin, V. I.; Samarina, M. V.; Zakharov, V. V.
2009-11-01
The effect of different modes of three-stage aging on the structure and properties of hot-deformed semiproducts (pressed shapes and rolled plates) from high-strength aluminum alloy V96Ts-3 of the Al - Zn - Mg - Cu system is studied with the aim of optimizing the hardening heat treatment. Amode of three-stage aging convenient for commercial production and ensuring hot-deformed semiproducts from alloy V96Ts-3 with high strength at the state T1 level in combination with satisfactory corrosion resistance corresponding to state T2 is suggested.
High negative charge of a dust particle in a hot cathode discharge.
Arnas, C; Mikikian, M; Doveil, F
1999-12-01
Dust particle levitation experiments in a plasma produced by a hot filament discharge, operating at low argon pressure, are presented. The basic characteristics of a dust grain trapped in a plate sheath edge in these experimental conditions are reported. Taking into account the sheath potential profiles measured with a differential emissive probe diagnostic, the forces applied to an isolated dust grain can be determined. Two different experimental methods yield approximately the same value for the dust charge. The observed high negative charge is mainly due to the contribution of the primary electrons emitted by the filaments as predicted by a simple model.
Laser properties of Fe2+:ZnSe fabricated by solid-state diffusion bonding
NASA Astrophysics Data System (ADS)
Balabanov, S. S.; Firsov, K. N.; Gavrishchuk, E. M.; Ikonnikov, V. B.; Kazantsev, S. Yu; Kononov, I. G.; Kotereva, T. V.; Savin, D. V.; Timofeeva, N. A.
2018-04-01
The characteristics of an Fe2+:ZnSe laser at room temperature and its active elements with undoped faces were studied. Polycrystalline elements with one or two diffusion-doped internal layers were obtained by the solid-state diffusion bonding technique applied to chemical vapor deposition grown ZnSe plates preliminary doped with Fe2+ ions in the process of hot isostatic pressing. A non-chain electric-discharge HF laser was used to pump the crystals. It was demonstrated that increasing the number of doped layers allows increasing the maximum diameter of the pump radiation spot and the pump energy without the appearance of transversal parasitic oscillation. For the two-layer-doped active element with a diameter of 20 mm an output energy of 480 mJ was achieved with 37% total efficiency with respect to the absorbed energy. The obtained results demonstrate the potential of the developed technology for fabrication of active elements by the solid-state diffusion bonding technique combined with the hot isostatic pressing treatment for efficient IR lasers based on chalcogenides doped with transition metal ions.
Dada, E. O.; Ekundayo, F. O.; Makanjuola, O. O.
2014-01-01
This study investigated the antibacterial activities of hot water, ethanol and acetone extracts of Jatropha curcas (LINN) leaves on coliforms isolated from surface waters using growth inhibition indices based on agar plate technique. The percentage recovery of the extracts was 19.17%, 18.10% and 18.80% for hot water, ethanol and acetone respectively. Phytochemical screening of the extracts was also determined. Qualitative phytochemical screening showed that the plant extracts contained steroids, tannins, flavonoids and cardiac glycosides, while alkaloids, phlobatannin, terpenoids and anthraquinones were absent. Only ethanolic extract did not possess saponins. Aqueous extracts of J. curcas compared most favourably with the standard antibiotics (gentamycin) on all the coliform bacteria except on K. pneumoniae and E. coli likely due to a measurably higher antibacterial activity compared to the organic extracts. The minimum inhibitory concentration of the aqueous extract ranged from 3.00 to 7.00 mg/L while minimum bactericidal concentration ranged from 4.00 to 10.00 mg/L. Aqueous extract of J. curcas could be used as antibacterial agents against diseases caused by coliforms. PMID:24711746
Partial analysis of LDEF experiment A-0114
NASA Technical Reports Server (NTRS)
Gregory, John C.
1991-01-01
During the contract period, work concentrated on four main components. Data from the UAH silver pin hole camera was analyzed for determination of the mean Long Duration Exposure Facility (LDEF) satellite attitude and stability in orbit, to include pitch and yaw. Chemical testing performed on the AO-114 hot plate determined the form and locus of absorption of cosmogenic beryllium-7. Reaction rates of atomic oxygen with Kapton and other polymeric solids integrated over the whole LDEF orbital lifetime were analyzed. These rates were compared with the JSC estimated values for Space Station exposures. Metal and polymer films exposed on A0114 (C-9 and C-3 plates) were also analyzed.
The effect of free-stream turbulence on heat transfer from a flat plate
NASA Technical Reports Server (NTRS)
Sugawara, Sugao; Sato, Takashi; Komatsu, Hiroyasu; Osaka, Hiroichi
1958-01-01
Turbulence was generated by using screens, and the turbulence percentage was measured by a hot-wire anemometer both in the boundary layer and the free stream. The local heat-transfer coefficient was measured at 12 locations along the plate for the cases of various turbulence levels. The transition Reynolds number from laminar to turbulent flow decreases as the main-stream turbulence level increases. In the range of laminar heat transfer the effect of turbulence in the main flow was not great, but in the range of turbulent heat transfer the heat-transfer coefficient increases according to the increase of turbulence.
Investigating the Origin of Silica Occurrences on Mars through Laboratory Observations
NASA Astrophysics Data System (ADS)
Ruff, S. W.; Milliken, R. E.; Farmer, J. D.; Mills, V. W.; Robertson, K.
2012-12-01
Natural amorphous "opaline" silica is a non-crystalline, typically hydrated phase of nearly pure SiO2 that is a common product of aqueous alteration of basaltic materials [e.g., 1]. It has been identified on Mars with orbital spectral data [2] and in situ measurements from the Spirit rover [3]. On Earth, opaline silica is produced over a range of temperature, pH, and water-to-rock ratio conditions that occur in hot springs, fumaroles, volcanic exhalations, low temperature weathering, and diagenesis [e.g., 4 and references therein]. The mere identification of silica on Mars therefore does not indicate a unique geologic environment or setting. However, various attributes of a given silica occurrence can be used to narrow or perhaps uniquely define the conditions in which it formed. Field relationships, microtexture, bulk and trace element chemistry, and spectral characteristics provide clues to the geologic environment in which the silica formed. Here we focus on the opaline silica in outcrops and soil at the Home Plate feature in Gusev crater where there is good evidence for past hydrothermal processes [3]. Unresolved is whether fumaroles, hot springs, geysers, or some combination of these features were present and responsible for the emplacement of opaline silica there. Knowing the answer has implications for understanding ancient climate and habitability of Mars. We have begun an investigation involving a range of laboratory measurements on natural silica-rich samples collected from various settings in Yellowstone and Hawaii Volcanoes National Parks. Visible and near infrared (VNIR) and thermal infrared (TIR) spectral measurements are supplemented with X-ray powder diffraction, scanning electron microscopy, petrographic microscopy, and ultimately with bulk and trace element measurements. Among our emerging results: 1) both VNIR and TIR spectra can detect the presence of <2 μm silica coatings on altered basalts; 2) VNIR spectra of silica from different environments exhibit only subtle differences, likely controlled primarily by variations in water content; and 3) fumarolic silica appears to have TIR spectral characteristics distinct from hot spring silica. This last result applies to samples of basaltic rocks enriched in silica by acid-sulfate leaching from Sulfur Banks, HI, which has been suggested as an analog for the Home Plate silica [3]. TIR spectra of four samples display only a weak feature near 8 μm related to high emission angle compared to that observed in hot spring silica sinter from Yellowstone. This spectral behavior may arise from microtextural or contaminant differences between the two kinds of silica. TIR spectra of Home Plate silica display a strong 8-μm feature like those of hot spring silica. If this preliminary result survives subsequent scrutiny, it may provide additional insight into the nature of the Home Plate hydrothermal system, the first to be investigated in situ on Mars. [1] McLennan, S. M. (2003), Geology, 31, 4, 315-318, [2] Milliken, R. E., et al. (2008), Geology, 36, 11, 847-850, 10.1130/G24967A.1. [3] Squyres, S. W., et al. (2008), Science, 320, 1063-1067, [4] Ruff, S. W., et al. (2011), J. Geophys. Res., 116, E00F23, 10.1029/2010JE003767.
NASA Astrophysics Data System (ADS)
MacPherson, C. G.; Hall, R.
2002-12-01
The petrology of volcanic rocks from the St. Andrew Strait and helium isotope ratios of backarc lavas from the Manus Basin have been used to propose the existence of an active hotspot beneath the eastern Bismarck Sea [1,2]. The possible influence of this hotspot can be assessed by mapping its present location onto a plate tectonic reconstruction of the western Pacific [3,4]. During the Middle Eocene the nascent Izu-Bonin-Mariana (IBM) arc lay above the hotspot. The volume of magma emplaced at the IBM arc at that time substantially exceeds the average magma production rate for mature island arcs. Furthermore, the ultramafic (boninitic) character of much of this magmatism requires elevated temperatures in the mantle. The geochemistry of contemporaneous magmatism in the backarc resembles melts usually found at ocean islands and much of the backarc region experienced significant uplift at that time. All of these features can be explained by the influx of hot, buoyant, chemically distinct mantle beneath the IBM and its hinterland. The plates lying above the hotspot during the later Eocene were subsequently subducted, but plate reconstruction suggests that during the Oligo-Miocene it was crossed by parts of the Caroline Plate where the Euripik Rise is found. This is an aseismic rise that possesses the geophysical characteristics of thickened oceanic crust formed by excess, basaltic magmatism and is the type of structure that would result from the passage of relatively young oceanic lithosphere over a mantle hotspot. Plate reconstruction for the western Pacific predicts a hotspot trail that is consistent with the Middle Eocene and Oligo-Miocene geology of the IBM and Caroline Plates, respectively. Parts of the trail have been disrupted by subsequent sea-floor spreading or lost through subduction but the remaining vestiges are consistent with the action of a thermal anomaly throughout much of the Cenozoic. More speculatively, the difference in buoyancy between the IBM, supported by hot mantle, and older, colder lithosphere of the adjacent Pacific Plate may have provided a mechanism to propagate widespread subduction at the nascent IBM arc, which has recently been shown to predate the postulated change in direction of the Pacific Plate during the Eocene [5]. [1] Johnson et al. 1978, BMR J. Aus. Geol. and Geophys. 3, 55. [2] Macpherson et al. 1998, Geology 26, 1007. [3] Hall 2002, J. Asian. Earth Sci. 20, 353. [4] Macpherson et al. 2001 EPSL 186, 215. [5] Cosca et al. 1998 Island Arc 7, 579.
Texture evolution and mechanical anisotropy of biomedical hot-rolled Co-Cr-Mo alloy.
Mori, Manami; Yamanaka, Kenta; Sato, Shigeo; Chiba, Akihiko
2015-11-01
Crystallographic textures and their effect on the mechanical anisotropy of a hot-rolled biomedical Co-Cr-Mo alloy were investigated. The hot-rolled Co-28Cr-6Mo-0.13N (mass%) alloy examined here exhibited a monotonic strength increment following hot-rolling reduction, eventually reaching a 0.2% proof stress of 1400 MPa while maintaining acceptable ductility (>10%). The dominant hot-rolling texture was a brass-type component, which is characterized by the alloy's peculiarly low stacking fault energy (SFE) even at hot rolling temperatures, although the minor peaks of the near copper component were also identified. However, because of the onset of dynamic recrystallization (DRX) during the hot rolling process, the texture intensity was relatively weak even after 90% hot rolling, although the grain refinement originating from the DRX was not significant (the "less active DRX" condition increased the strain accumulation during the process, resulting in high-strength samples). The weakened texture development resulted in negligible in-plane anisotropy for the hot-rolled specimen strength, when the specimens were tensile strained in the rolling direction (RD) and transverse direction (TD). The elongation-to-failure, however, exhibited a difference with respect to the tensile loading axis. It is suggested that the ductility anisotropy is closely related to a strain-induced γ (fcc) → ε (hcp) martensitic transformation during tensile loading, resulting in a difference in the proportion of quasi-cleavage fracture surfaces. The obtained results will be helpful in the development of high-strength Co-Cr-Mo alloy plates and sheets, and have implications regarding plastic deformation and texture evolution during the hot rolling of non-conventional metallic materials with low SFE at elevated temperatures, where planar dislocation slips of Shockley partial dislocations and thermally activated process interplay. Copyright © 2015 Elsevier Ltd. All rights reserved.
Welds in thermoplastic composite materials
NASA Astrophysics Data System (ADS)
Taylor, N. S.
Welding methods are reviewed that can be effectively used for joining of thermoplastic composites and continuous-fiber thermoplastics. Attention is given to the use of ultrasonic, vibration, hot-plate, resistance, and induction welding techniques. The welding techniques are shown to provide complementary weld qualities for the range of thermoplastic materials that are of interest to industrial and technological applications.
2017-06-01
11 Table 1 Notation for fabric and ensemble resistances . .......................................... 13 Thermal manikin...Table 1 Notation for fabric and ensemble resistances .................................................. 13 Table 2 Weight reduction of CB garment...samples were tested on a Sweating Guarded Hot Plate (SGHP) to measure fabric thermal and evaporative resistance , respectively. The ensembles were tested
46 CFR 105.20-3 - Cargo tanks.
Code of Federal Regulations, 2010 CFR
2010-10-01
...) Construction and Materials. (1) The cargo tanks must be constructed of iron, steel, copper, nickel alloy, copper alloy; or aluminum. The tanks shall be designed to withstand the maximum head to which they may be... inches and gage number 2,3 Nickel copper B127, hot rolled sheet or plate 0.107 (USSG 12). Copper nickel 1...
Study of Improved Aluminum Materials for Vehicular Armor
1977-04-07
and along cell walls. Dislocations generated during deformation cf the 17 -------------- recrystallized structure interacted with the grain...unrecrystallized (HR) 7475 plate containing dislocations within subgrains and along cell walls. Hot rolling the recrystallized structure at 750OF produced...a structure after solution heat treatment that consisted of elongated recrystallized grains containing polygonized cells . This structure developed
Solar-energy landmark Building-Columbia, Missouri
NASA Technical Reports Server (NTRS)
1981-01-01
Report includes design, cost, installation, maintenance, and performance details for attractive solar installation which supplies space heating for four-story Visitors Center. 176 hydronic flat-plate collectors, water-to-water heat exchanger, and 5,000-gallon storage tank comprise system which provides 71 percent of building's heat. Natural-gas-fired boiler supplies auxiliary hot water to heating system when necessary.
Solar energy system performance evaluation: Seasonal report for IBM System 2, Togus, Maine
NASA Technical Reports Server (NTRS)
1980-01-01
The solar energy system, SIMS Prototype System 2, was designed to supply domestic hot water to single family residences. The system consists of flat plate collectors, silicone working fluid, storage tanks, pumps, heat exchanger, controls, and associated plumbing. The long term field performance of the installed system was analyzed and the results are described.
Measurement of heat transfer coefficient using termoanemometry methods
NASA Astrophysics Data System (ADS)
Dančová, P.; Sitek, P.; Vít, T.
2014-03-01
This work deals with a measurement of heat transfer from a heated flat plate on which a synthetic jet impacts perpendicularly. Measurement of a heat transfer coefficient (HTC) is carried out using the hot wire anemometry method with glue film probe Dantec 55M47. The paper brings also results of velocity profiles measurements and turbulence intensity calculations.
Analgesic Effect of Xenon in Rat Model of Inflammatory Pain.
Kukushkin, M L; Igon'kina, S I; Potapov, S V; Potapov, A V
2017-02-01
The analgesic effects of inert gas xenon were examined on rats. The formalin model of inflammatory pain, tail-flick test, and hot-plate test revealed the antinociceptive effects of subanesthetizing doses of inhalation anesthetic xenon. Inhalation of 50/50 xenon/oxygen mixture moderated the nociceptive responses during acute and tonic phases of inflammatory pain.
NASA Astrophysics Data System (ADS)
Biradar, N. S.; Raman, R.
2012-09-01
Hot cracking studies on autogenous AA2014 T6 TIG welds were carried out. Significant cracking was observed during linear and circular welding test (CWT) on 4-mm-thick plates. Weld metal grain structure and amount of liquid distribution during the terminal stages of solidification were the key cause for hot cracking in aluminum welds. Square-wave AC TIG welding with transverse mechanical arc oscillation (TMAO) was employed to study the cracking behavior during linear and CWT. TMAO welds with amplitude = 0.9 mm and frequency = 0.5 Hz showed significant reduction in cracking tendency. The increase in cracking resistance in the arc-oscillated weld was attributed to grain refinement and improved weld bead morphology, which improved the weld metal ductility and uniformity, respectively, of residual tensile stresses that developed during welding. The obtained results were comparable to those of reported favorable results of electromagnetic arc oscillation.
Development of monolithic nuclear fuels for RERTR by hot isostatic pressing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jue, J.-F.; Park, Blair; Chapple, Michael
2008-07-15
The RERTR Program (Reduced Enrichment for Research and Test Reactors) is developing advanced nuclear fuels for high power test reactors. Monolithic fuel design provides a higher uranium loading than that of the traditional dispersion fuel design. In order to bond monolithic fuel meat to aluminum cladding, several bonding methods such as roll bonding, friction stir bonding and hot isostatic pressing, have been explored. Hot isostatic pressing is a promising process for low cost, batch fabrication of monolithic RERTR fuel plates. The progress on the development of this process at the Idaho National Laboratory will be presented. Due to the relativelymore » high processing temperature used, the reaction between fuel meat and aluminum cladding to form brittle intermetallic phases may be a concern. The effect of processing temperature and time on the fuel/cladding reaction will be addressed. The influence of chemical composition on the reaction will also be discussed. (author)« less
Solar heating and hot water system installed at Arlington Raquetball Club, Arlington, Virginia
NASA Technical Reports Server (NTRS)
1981-01-01
A solar space and water heating system is described. The solar energy system consists of 2,520 sq. ft. of flat plate solar collectors and a 4,000 gallon solar storage tank. The transfer medium in the forced closed loop is a nontoxic antifreeze solution (50 percent water, 50 percent propylene glycol). The service hot water system consists of a preheat coil (60 ft. of 1 1/4 in copper tubing) located in the upper third of the solar storage tank and a recirculation loop between the preheat coil and the existing electric water heaters. The space heating system consists of two separate water to air heat exchangers located in the ducts of the existing space heating/cooling systems. The heating water is supplied from the solar storage tank. Extracts from site files, specification references for solar modifications to existing building heating and hot water systems, and installation, operation and maintenance instructions are included.
Performance study of thermo-electric generator
NASA Astrophysics Data System (ADS)
Rohit, G.; Manaswini, D.; Kotebavi, Vinod; R, Nagaraja S.
2017-07-01
Devices like automobiles, stoves, ovens, boilers, kilns and heaters dissipate large amount of waste heat. Since most of this waste heat goes unused, the efficiency of these devices is drastically reduced. A lot of research is being conducted on the recovery of the waste heat, among which Thermoelectric Generators (TEG) is one of the popular method. TEG is a semiconductor device that produces electric potential difference when a thermal gradient develops on it. This paper deals with the study of performance of a TEG module for different hot surface temperatures. Performance characteristics used here are voltage, current and power developed by the TEG. One side of the TEG was kept on a hot plate where uniform heat flux was supplied to that. And the other side was cooled by supplying cold water. The results show that the output power increases significantly with increase in the temperature of the hot surface.
The occurrence of Salmonella in airline meals.
Hatakka, M; Asplund, K
1993-01-01
The occurrence of Salmonella in airline meals was studied in 1989-1992. Samples were collected from flight kitchens in 29 countries. The material consisted of 400 cold dishes and 1,288 hot dishes as well as salads, cheese plates and deserts. Total number of samples was 2211. Salmonella spp. were isolated from 6 samples; 1 contaminated sample was a cold dish prepared in Bangkok, 1 was a hot dish prepared in Mombasa and the remaining 4 contaminated samples were hot dishes prepared within one week in Beijing. The isolated serotypes were S. ohio, S. manchester and S. braenderup. The contaminated cold dish prepared by a flight kitchen in Bangkok was found to be connected with a Salmonella outbreak which occurred in Finland in 1990. Cold airline dishes containing food of animal origin seems to be more risky as a source of Salmonella infections among airline passengers.
Biodegradable compounds: Rheological, mechanical and thermal properties
NASA Astrophysics Data System (ADS)
Nobile, Maria Rossella; Lucia, G.; Santella, M.; Malinconico, M.; Cerruti, P.; Pantani, R.
2015-12-01
Recently great attention from industry has been focused on biodegradable polyesters derived from renewable resources. In particular, PLA has attracted great interest due to its high strength and high modulus and a good biocompatibility, however its brittleness and low heat distortion temperature (HDT) restrict its wide application. On the other hand, Poly(butylene succinate) (PBS) is a biodegradable polymer with a low tensile modulus but characterized by a high flexibility, excellent impact strength, good thermal and chemical resistance. In this work the two aliphatic biodegradable polyesters PBS and PLA were selected with the aim to obtain a biodegradable material for the industry of plastic cups and plates. PBS was also blended with a thermoplastic starch. Talc was also added to the compounds because of its low cost and its effectiveness in increasing the modulus and the HDT of polymers. The compounds were obtained by melt compounding in a single screw extruder and the rheological, mechanical and thermal properties were investigated. The properties of the two compounds were compared and it was found that the values of the tensile modulus and elongation at break measured for the PBS/PLA/Talc compound make it interesting for the production of disposable plates and cups. In terms of thermal resistance the compounds have HDTs high enough to contain hot food or beverages. The PLA/PBS/Talc compound can be, then, considered as biodegradable substitute for polystyrene for the production of disposable plates and cups for hot food and beverages.
Mass Spectrometric Detection of Botulinum Neurotoxin by Measuring its Activity in Serum and Milk
NASA Astrophysics Data System (ADS)
Kalb, Suzanne R.; Pirkle, James L.; Barr, John R.
Botulinum neurotoxins (BoNTs) are bacterial protein toxins which are considered likely agents for bioterrorism due to their extreme toxicity and high availability. A new mass spectrometry based assay called Endopep MS detects and defines the toxin serotype in clinical and food matrices via toxin activity upon a peptide substrate which mimics the toxin's natural target. Furthermore, the subtype of the toxin is differentiated by employing mass spectrometry based proteomic techniques on the same sample. The Endopep-MS assay selectively detects active BoNT and defines the serotype faster and with sensitivity greater than the mouse bioassay. One 96-well plate can be analyzed in under 7 h. On higher level or "hot" samples, the subtype can then be differentiated in less than 2 h with no need for DNA.
NASA Astrophysics Data System (ADS)
Garifo, Mary Anna
2017-04-01
Geographic Information System, GIS, is a powerful tool and when incorporated into Earth Science classrooms, can enhance and empower students' engagement in their learning. Through utilization of GIS, students can process what they are learning in a spatially orientated method, which allows them to make connections among different related concepts. For example, if students are given a map in a GIS software with multiple layers of data on earthquakes, plate technics, and volcanoes then they can manipulate this information to come up with their own patterns. Through allowing students to develop their spatial recognition of where the Earth's plate boundaries are and where earthquakes have occurred, students can see how these two concepts are connected. In a guided but exploratory activity, students would be given multiple different websites that they could explore to research what different type of plates there are while they are working simultaneously with the GIS software. Using a plate technics layer, including data on type of boundary, students can explore and estimate which direction the plates are moving. When they look up convergent boundaries and see that the oceanic plates submerge under continental plates they can see where volcanic chains might be. Once they understand this in a spatial way, students can predict where they think volcanoes could be, based on where convergent boundaries are. When they manipulate the volcanic layer and see abnormalities to what they just learned, it will cause them to have cognitive dissonance, which will force them into seeking further understanding. The concept of a hot spot can then be introduced to resolve the cognitive dissonance and emphasis the idea that plates we live on are moving. Concepts can further be developed through GIS by showing how the strength and frequency of earthquakes are related to the level of activity at the plate boundary. This can be done by manipulating the map layer that represents earthquakes so that students can visualize each earthquake based on depth, size, or just location. If it is more active, then students should predict which direction it is moving based on the different boundary types. Rather than a traditional lecture approach, GIS software enables students to explore and manipulate relevant variables in an interactive and stimulating environment. It can harness their sense of wonder and exploration by giving them the opportunity to be hands on with the technology. In addition, using GIS in an Earth Science classroom can foster empathy in students. When the students look at the dots on the map, the hope is that they can visualize what type of destruction that could happen, especially when they change the variable function based on location to magnitude. As a teacher in Virginia, U.S.A., most students here have not experienced an earthquake. Although their perspective is limited, by allowing them to explore different locations with GIS, they create connections with places where earthquakes occur. The data and information they use allows them to learn about how the earth's systems are not isolated events but are the reality people live in.
Dagenais, P; Desprez, B; Albert, J; Escher, E
1994-10-01
Direct adsorption of small peptide antigens to unaltered, commercially available polystyrene surfaces may be too weak to permit suitable assay by ELISA. We therefore developed a simple method for the covalent attachment of small, potentially single epitope antigens to polystyrene surfaces. Chemical activation of polystyrene plates with carbodiimide considerably improves the total and covalent attachment of radioactive octapeptides. The covalent attachment was demonstrated by washing with hot detergent. A 3.5 Mrad gamma-irradiation of plates also increases total binding, particularly in combination with chemical activation. The covalent attachment presumably occurs through formation and chemical activation of carboxylate functions on the polystyrene surface which form amide bonds with peptides. ELISA test was performed with CGRP and successive smaller CGRP fragments. Covalent attachment of C-terminal peptide fragments as detection antigens allows optimal recognition and sensitivity even for hexapeptides, while decapeptide antigens were already poorly recognized using a conventional antigen plating technique. Repetitive detergent washes and/or prolonged storage of plates with covalently bound antigens did not reduce their ELISA sensitivity. The method with storage and reutilization capacities that we present here will be useful for the development of preplated antibody screening test.
Solar energy system performance evaluation report for IBM System 4 at Clinton, Mississippi
NASA Technical Reports Server (NTRS)
1980-01-01
The IBM System 4 Solar Energy System is described and evaluated. The system was designed to provide 35 percent of the space heating and 63 percent of the domestic hot water preheating for a single family residence located within the United States. The system consists of 259 square feet of flat plate air collectors, a rock thermal storage containing 5 1/2 ton of rock, heat exchangers, blowers, a 52 gallon preheat tank, controls, and associated plumbing. In general, the performance of the system did not meet design expectations, since the overall design solar fraction was 48 percent and the measured value was 32 percent. Although the measured space heating solar fraction at 32 percent did agree favorably with the design space heating solar fraction at 35 percent, the hot water measured solar fraction at 33 percent did not agree favorably with the design hot water solar fraction of 63 percent. In particular collector array air leakage, dust covered collectors, abnormal hot water demand, and the preheat tank by pass valve problem are main reasons for the lower performance.
RERTR-10 Irradiation Summary Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
D. M. Perez
2011-05-01
The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-10 was designed to further test the effectiveness of modified fuel/clad interfaces in monolithic fuel plates. The experiment was conducted in two campaigns: RERTR-10A and RERTR-10B. The fuel plates tested in RERTR-10A were all fabricated by Hot Isostatic Pressing (HIP) and were designed to evaluate the effect of various Si levels in the interlayer and the thickness of the Zr interlayer (0.001”) using 0.010” and 0.020” nominal foil thicknesses. The fuel plates in RERTR-10B were fabricated by Friction Bonding (FB) with two different thickness Si layers and Nb and Zrmore » diffusion barriers.1 The following report summarizes the life of the RERTR-10A/B experiment through end of irradiation, including as-run neutronic analysis results, thermal analysis results and hydraulic testing results.« less
Increasing thermal efficiency of solar flat plate collectors
NASA Astrophysics Data System (ADS)
Pona, J.
A study of methods to increase the efficiency of heat transfer in flat plate solar collectors is presented. In order to increase the heat transfer from the absorber plate to the working fluid inside the tubes, turbulent flow was induced by installing baffles within the tubes. The installation of the baffles resulted in a 7 to 12% increase in collector efficiency. Experiments were run on both 1 sq ft and 2 sq ft collectors each fitted with either slotted baffles or tubular baffles. A computer program was run comparing the baffled collector to the standard collector. The results obtained from the computer show that the baffled collectors have a 2.7% increase in life cycle cost (LCC) savings and a 3.6% increase in net cash flow for use in domestic hot water systems, and even greater increases when used in solar heating systems.
Use of hot water for beef carcass decontamination.
Castillo, A; Lucia, L M; Goodson, K J; Savell, J W; Acuff, G R
1998-01-01
Hot water treatment of beef carcass surfaces for reduction of Escherichia coli O157:H7, Salmonella typhimurium, and various indicator organisms was studied using a model carcass spray cabinet. Paired hot carcass surface regions with different external fat characteristics (inside round, outside round, brisket, flank, and clod) were removed from carcasses immediately after the slaughter and dressing process. All cuts were inoculated with bovine feces containing 10(6)/g each of rifampicin-resistant E. coli O157:H7 and S. typhimurium, or with uninoculated bovine feces. Surfaces then were exposed to a carcass water wash or a water wash followed by hot water spray (95 degrees C). Counts of rifampicin-resistant Salmonella and E. coli or aerobic plate count (APC) and coliform counts were conducted before and after each treatment. All treatments significantly reduced levels of pathogens from the initial inoculation level of 5.0 log(10) CFU/cm2. Treatments including hot water sprays provided mean reductions of initial counts for E. coli O157:H7 and S. typhimurium of 3.7 and 3.8 log, APC reductions of 2.9 log, and coliform and thermotolerant coliform count reductions of 3.3 log. The efficacy of hot water treatments was affected by the carcass surface region, but not by delaying the treatment (30 min) after contaminating the surface. Verification of efficacy of hot water interventions used as critical control points in a hazard analysis critical control point (HACCP) system may be possible using coliform counts.
What controls the distribution and tectono-magmatic features of oceanic hot spot volcanoes
NASA Astrophysics Data System (ADS)
Acocella, Valerio; Vezzoli, Luigina
2016-04-01
Hot spot oceanic volcanoes worldwide show significant deviations from the classic Hawaiian reference model; these mainly concern the distribution of edifices and overall tectono-magmatic features, as the development of the volcanic rift zones and extent of flank instability. Here we try to explain these deviations investigating and comparing the best-known hot spot oceanic volcanoes. At a general scale, these volcanoes show an age-distance progression ranging from focused to scattered. This is here explained as due to several independent factors, as the thermal or mechanical weakening of the plate (due to the lithosphere thickness or regional structures, respectively), or the plume structure. At a more detailed scale, hot spot volcanoes show recurrent features, including mafic shield edifices with summit caldera and volcanic rift zones, often at the head of an unstable flank. However, despite this recurrence, a widespread tectono-magmatic variability is often found. Here we show how this variability depends upon the magma supply and age of the oceanic crust (influencing the thickness of the overlying pelagic sediments). Well-developed rift zones and larger collapses are found on hot spot volcanoes with higher supply rate and older crust, as Hawaii and Canary Islands. Poorly-developed rift zones and limited collapses occur on hot spot volcanoes with lower supply rate and younger crust, as Easter Island and Ascension. Transitional features are observed at hot spots with intermediate productivity (Cape Verde, Reunion, Society Islands and, to a minor extent, the Azores), whereas the scarcity or absence of pelagic sediments may explain the lack of collapses and developed rift zones in the productive Galapagos hot spot.
Landing Gear Components Noise Study - PIV and Hot-Wire Measurements
NASA Technical Reports Server (NTRS)
Hutcheson, Florence V.; Burley, Casey L.; Stead, Daniel J.; Becker, Lawrence E.; Price, Jennifer L.
2010-01-01
PIV and hot-wire measurements of the wake flow from rods and bars are presented. The test models include rods of different diameters and cross sections and a rod juxtaposed to a plate. The latter is representative of the latch door that is attached to an aircraft landing gear when the gear is deployed, while the single and multiple rod configurations tested are representative of some of the various struts and cables configuration present on an aircraft landing gear. The test set up is described and the flow measurements are presented. The effect of model surface treatment and freestream turbulence on the spanwise coherence of the vortex shedding is studied for several rod and bar configurations.
Patrick, T E; Goodwin, T L; Collins, J A; Wyche, R C; Love, B E
1972-04-01
A comparison of two types of scalders was conducted to determine their effectiveness in reducing bacterial contamination of poultry carcasses. A conventional hot-water scalder and a prototype model of a steam scalder were tested under commercial conditions. Total plate counts from steam-scalded birds were significantly lower than the counts of water-scalded birds immediately after scalding and again after picking. No differences in the two methods could be found after chilling. Coliform counts from steam-scalded birds were significantly lower than the counts from water-scalded birds immediately after scalding. No significant differences in coliform counts were detected when the two scald methods were compared after defeathering and chilling.
African hot spot volcanism: small-scale convection in the upper mantle beneath cratons.
King, S D; Ritsema, J
2000-11-10
Numerical models demonstrate that small-scale convection develops in the upper mantle beneath the transition of thick cratonic lithosphere and thin oceanic lithosphere. These models explain the location and geochemical characteristics of intraplate volcanos on the African and South American plates. They also explain the presence of relatively high seismic shear wave velocities (cold downwellings) in the mantle transition zone beneath the western margin of African cratons and the eastern margin of South American cratons. Small-scale, edge-driven convection is an alternative to plumes for explaining intraplate African and South American hot spot volcanism, and small-scale convection is consistent with mantle downwellings beneath the African and South American lithosphere.
Composite material reinforced with atomized quasicrystalline particles and method of making same
Biner, Suleyman B.; Sordelet, Daniel J.; Lograsso, Barbara K.; Anderson, Iver E.
1998-12-22
A composite material comprises an aluminum or aluminum alloy matrix having generally spherical, atomized quasicrystalline aluminum-transition metal alloy reinforcement particles disposed in the matrix to improve mechanical properties. A composite article can be made by consolidating generally spherical, atomized quaiscrystalline aluminum-transition metal alloy particles and aluminum or aluminum alloy particles to form a body that is cold and/or hot reduced to form composite products, such as composite plate or sheet, with interfacial bonding between the quasicrystalline particles and the aluminum or aluminum alloy matrix without damage (e.g. cracking or shape change) of the reinforcement particles. The cold and/or hot worked compositehibits substantially improved yield strength, tensile strength, Young's modulus (stiffness).
Solar space heating for the Visitors Center, Stephens College, Columbia, Missouri
NASA Technical Reports Server (NTRS)
1980-01-01
The solar energy system located at the Visitors' Center on the Stephens College Campus, Columbia, Missouri is discussed. The system is installed in a four-story, 15,000 square foot building. The solar energy system is an integral design of the building and utilizes 176 hydronic flat plate collectors which use a 50 percent water ethylene blycol solution and water-to-water heat exchanger. Solar heated water is stored in a 5,000 gallon water storage tank located in the basement equipment room. A natural gas fired hot water boiler supplies hot water when the solar energy heat supply fails to meet the demand. The designed solar contribution is 71 percent of the heating load.
2008-12-01
Figure 4. B4C plates formed via hot pressing with a curved shape. Commercial B4C shows a large number of lenticular graphitic inclusions, Figure 5...materials and they act as crack initiation points in flexure testing. Figure 5. SEM micrograph showing large lenticular graphitic inclusions in commercial
Synthesis and analgetic activity of 1,2,3,4,5,6-hexahydro-1,6-methano-3-benzozocines.
Mazzocchi, P H; Harrison, A M
1978-02-01
1,2,3,4,5,6-Hexahydro-1,6-methano-3-benzazocine (1) has been synthesized via a four-step sequence from benzo-norbornadiene. This compound and its N-methyl derivative are more active than codeine in the mouse hot-plate antinociceptive assay and will not suppor morphine dependence in Rhesus monkeys.
2013-03-01
materials have been introduced as dopants: Vanadium (V), Chromium (Cr), Manganese (Mn), Lead (Pb), and Iron (Fe) [41, 42, 43, 44]. While these...value reported in literature, 188°C, due to the samples being heated on an open air hot plate in a laminar flow fume hood. The average resistivity of
Eddy current sensing of intermetallic composite consolidation
NASA Technical Reports Server (NTRS)
Dharmasena, Kumar P.; Wadley, Haydn N. G.
1991-01-01
A finite element method is used to explore the feasibility and optimization of a probe-type eddy current sensor for determining the thickness of plate specimens during a hot isostatic pressing cycle. The dependence of the sensor's impedance upon sample-sensor separation in the high frequency limit is calculated, and factors that maximize sensitivity to the final stages of densification are identified.
Meshram, Girish G; Kumar, Anil; Rizvi, Waseem; Tripathi, C D; Khan, R A
2015-01-01
Albizia lebbeck Benth. is extensively used in Indian traditional medicine for treating several painful and inflammatory disorders. The possible central analgesic activity and the underlying mechanism of action of the aqueous (AE) and ethanolic extracts (EE) of the leaves of A. lebbeck were investigated in Wistar rats using Eddy's hot plate and the tail flick tests. In order to investigate the underlying mechanism of action, rats were pretreated with naloxone, bicuculline or methysergide and then were administered a per os (p.o.) dose of AE or EE. AE and EE caused a significant (p<0.05) elevation in the mean basal reaction time in the hot plate method and an increase in the latency time in the tail flick method. In rats pretreated with bicuculline and methysergide, a significant (p<0.05) reduction in the analgesic activity was observed in comparison to AE and EE. Thus, AE and EE exhibited significant central analgesic activity and act possibly via the GABAergic and serotonergic pathways. The flavonoids and saponins found in the leaves could be responsible for the observed effect.
NASA Astrophysics Data System (ADS)
Kashif, Ismail; Soliman, Ashia A.; Sakr, Elham M.; Ratep, Asmaa
2012-01-01
The glass system (45Li2O + 45B2O3 + 10Nb2O5) was fabricated by the conventional melt quenching technique poured in water, at air, between two hot plates and droplets at the cooled surface. The glass and glass ceramics were studied by differential thermal analysis (DTA) and X-ray diffraction (XRD). The as quenched samples poured in water and between two hot plates were amorphous. The samples poured at air and on cooled surface were crystalline as established via X-ray powder diffraction (XRD) studies. Differential thermal analysis was measured. The glass transition temperature (Tg) and the crystallization temperatures were calculated. Lithium niobate (LiNbO3) was the main phase in glass ceramic poured at air, droplets at the cooled surface and the heat treated glass sample at 500, 540 and 580 °C in addition to traces from LiNb3O8. Crystallite size of the main phases determined from the X-ray diffraction peaks is in the range of <100 nm. The fraction of crystalline (LiNbO3) phase decreases with increase in the heat treatment temperature.
Measuring Thermal Conductivity at LH2 Temperatures
NASA Technical Reports Server (NTRS)
Selvidge, Shawn; Watwood, Michael C.
2004-01-01
For many years, the National Institute of Standards and Technology (NIST) produced reference materials for materials testing. One such reference material was intended for use with a guarded hot plate apparatus designed to meet the requirements of ASTM C177-97, "Standard Test Method for Steady-State Heat Flux Measurements and Thermal Transmission Properties by Means of the Guarded-Hot-Plate Apparatus." This apparatus can be used to test materials in various gaseous environments from atmospheric pressure to a vacuum. It allows the thermal transmission properties of insulating materials to be measured from just above ambient temperature down to temperatures below liquid hydrogen. However, NIST did not generate data below 77 K temperature for the reference material in question. This paper describes a test method used at NASA's Marshall Space Flight Center (MSFC) to optimize thermal conductivity measurements during the development of thermal protection systems. The test method extends the usability range of this reference material by generating data at temperatures lower than 77 K. Information provided by this test is discussed, as are the capabilities of the MSFC Hydrogen Test Facility, where advanced methods for materials testing are routinely developed and optimized in support of aerospace applications.
Transition from moving to stationary double layers in a single-ended Q machine
NASA Technical Reports Server (NTRS)
Song, Bin; Merlino, R. L.; D'Angelo, N.
1990-01-01
Large-amplitude (less than about 100 percent) relaxation oscillations in the plasma potential are known to be generated when the cold endplate of a single-ended Q machine is biased positively. These oscillations are associated with double layers that form near the hot plate (plasma source) and travel toward the endplate at about the ion-acoustic velocity. At the endplate they dissolve and then form again near the hot plate, the entire process repeating itself in a regular manner. By admitting a sufficient amount of neutral gas into the system, the moving double layers were slowed down and eventually stopped. The production of stationary double layers requires an ion source on the high-potential side of the double layers. These ions are provided by ionization of the neutral gas by electrons that are accelerated through the double layer. The dependence of the critical neutral gas pressure required for stationary double-layer formation on endplate voltage, magnetic field strength, and neutral atom mass has been examined. These results are discussed in terms of a simple model of ion production and loss, including ion losses across the magnetic field.
Impact of early developmental fluoride exposure on the peripheral pain sensitivity in mice.
Ma, Jing; Liu, Fei; Liu, Peng; Dong, Ying-Ying; Chu, Zheng; Hou, Tie-Zhou; Dang, Yong-Hui
2015-12-01
Consumption of high concentration of fluoride in the drinking water would cause the fluorosis and chronic pain. Similar pain syndrome appeared in the patients in fluoride therapy of osteoporotic. The aim of the current study was to examine whether exposing immature mice to fluoride would modify the peripheral pain sensitivity or even cause a pain syndrome. We gave developmental fluoride exposure to mice in different concentration (0mg/L, 50mg/L and 100mg/L) and evaluated their basal pain threshold. Von Frey hair test, hot plate test and formalin test were conducted to examine the mechanical, thermal nociceptive threshold and inflammatory pain, respectively. In addition, the expression of hippocampal brain-derived neurotrophic factor (BDNF) was also evaluated by Western blotting. Hyperalgesia in fluoride exposure mice was exhibited in the Von Frey hair test, hot plate test and formalin test. Meanwhile, the expression of BDNF was significantly higher than that of control group. The results suggest that early developmental fluoride exposure may lower the basal pain threshold and be associated with the increasing of BDNF expression in hippocampus. Copyright © 2015 Elsevier Ltd. All rights reserved.
Analysis of modes of heat transfer in baking Indian rice pan cake (Dosa,) a breakfast food.
Venkateshmurthy, K; Raghavarao, K S M S
2015-08-01
Heat transfer by individual modes is estimated during baking of rice (Oryza sativa) pan cake (Dosa), a traditional food. The mathematical expressions proposed could be used to modify the baking oven for controlling the individual modes of heat transfer to obtain the desired product texture, colour and flavour. Conduction from the rotating hot plate is found to be the most prominent mode of heat transfer and is critical for obtaining the desired product characteristics such as texture and flavour. Temperature profiles along the thickness of Dosa are obtained and compared with those obtained experimentally. Heat transfer parameters such as thermal conductivity and emissivity of Dosa are determined (0.42 W/m K and 0.31, respectively). The effect of material of construction of the hot plate such as alloy steel, teflon coated aluminum, cast iron and stainless steel on product texture was studied and stainless steel was found to give good surface finish to the product, which was confirmed by scanning electron microscope. Sensory evaluation was carried out to evaluate the product acceptability. The thermal efficiency of the baking oven was 51.5%.
Evaluation of the antinociceptive activity of extracts of Sonchus oleraceus L. in mice.
Vilela, Fabiana Cardoso; de Mesquita Padilha, Marina; Dos Santos-E-Silva, Lucas; Alves-da-Silva, Geraldo; Giusti-Paiva, Alexandre
2009-07-15
Sonchus oleraceus L. has been used to relieve pain in Brazilian folk medicine. Sonchus oleraceus L. has been used to relieve pain in Brazilian folk medicine. This study was conducted to establish the antinociceptive properties of hydroethanolic and dichloromethane extracts from aerial parts of Sonchus oleraceus in mice using chemical and thermal models of nociception. The formalin, hot plate, and tail immersion tests as well as acetic acid-induced writhing were used to investigate the antinociceptive activity in mice. Given orally, the extracts at test doses of 30-300 mg/kg, produced significant inhibitions on chemical nociception induced by intraperitoneal acetic acid and subplantar formalin since decreased the number of writhing episodes and the time licking. Treatment with the extracts in the same doses produced a significant increase of the reaction time in tail immersion and in the hot plate test. The extracts administered at 300 mg/kg, p.o. had a stronger antinociceptive effect than indomethacin (5mg/kg, p.o.) and morphine (10mg/kg, p.o.). The extracts of Sonchus oleraceus markedly demonstrated antinociceptive action in mice, which supports previous claims of its traditional use.
Differential analgesic effects of a mu-opioid peptide, [Dmt(1)]DALDA, and morphine.
Shimoyama, Megumi; Szeto, Hazel H; Schiller, Peter W; Tagaito, Yugo; Tokairin, Hideyuki; Eun, Chong moon; Shimoyama, Naohito
2009-01-01
H-Dmt-D-Arg-Phe-Lys-NH(2) ([Dmt(1)]DALDA), a highly selective micro-opioid peptide, is potently analgesic after systemic and intrathecal administration but is less potent given intracerebroventricularly. This study was performed to further characterize the analgesic effects of [Dmt(1)]DALDA. We compared the effects of [Dmt(1)]DALDA and morphine after systemic administration in two different acute pain tests, the tail flick test and the paw withdrawal test, and examined how antagonizing the spinal opioid actions would affect their analgesic effects. [Dmt(1)]DALDA was markedly more potent in the tail flick test than in the hot plate test, while the potencies of morphine were similar in the two tests. Intrathecal naloxone completely blocked the effect of systemic [Dmt(1)]DALDA in the tail flick test, while it only partially blocked the effect of morphine. At higher doses that produced analgesia in the hot plate test, the effect of [Dmt(1)]DALDA in this test was only partially blocked by naloxone. Systemic [Dmt(1)]DALDA has a unique analgesic property clearly different from that of morphine and it has a propensity to produce spinal analgesia.
Study of the Performance of Stainless Steel A-TIG Welds
NASA Astrophysics Data System (ADS)
Shyu, S. W.; Huang, H. Y.; Tseng, K. H.; Chou, C. P.
2008-04-01
The purpose of the present work was to investigate the effect of oxide fluxes on weld morphology, arc voltage, mechanical properties, angular distortion and hot cracking susceptibility obtained with TIG welding, which applied to the welding of 5 mm thick austenitic stainless steel plates. A novel variant of the autogenous TIG welding process, oxide powders (Al2O3, Cr2O3, TiO2, SiO2 and CaO) was applied on a type 304 stainless steel through a thin layer of the flux to produce a bead on plate welds. The experimental results indicated that the increase in the penetration is significant with the use of Cr2O3, TiO2, and SiO2. A-TIG welding can increase the weld depth to bead-width ratio, and tends to reduce the angular distortion of the weldment. It was also found that A-TIG welding can increase the retained delta-ferrite content of stainless steel 304 welds and, in consequence, the hot-cracking susceptibility of as-welded is reduced. Physically constricting the plasma column and reducing the anode spot are the possible mechanism for the effect of certain flux on A-TIG penetration.
Study on vacuum packaging reliability of micromachined quartz tuning fork gyroscopes
NASA Astrophysics Data System (ADS)
Fan, Maoyan; Zhang, Lifang
2017-09-01
Packaging technology of the micromachined quartz tuning fork gyroscopes by vacuum welding has been experimentally studied. The performance of quartz tuning fork is influenced by the encapsulation shell, encapsulation method and fixation of forks. Alloy solder thick film is widely used in the package to avoid the damage of the chip structure by the heat resistance and hot temperature, and this can improve the device performance and welding reliability. The results show that the bases and the lids plated with gold and nickel can significantly improve the airtightness and reliability of the vacuum package. Vacuum packaging is an effective method to reduce the vibration damping, improve the quality factor and further enhance the performance. The threshold can be improved nearly by 10 times.
Vortex boundary-layer interactions
NASA Technical Reports Server (NTRS)
Bradshaw, P.
1986-01-01
Parametric studies to identify a vortex generator were completed. Data acquisition in the first chosen configuration, in which a longitudinal vortex pair generated by an isolated delta wing starts to merge with a turbulent boundary layer on a flat plate fairly close to the leading edge is nearly completed. Work on a delta-wing/flat-plate combination, consisting of a flow visualization and hot wire measurements taken with a computer controlled traverse gear and data logging system were completed. Data taking and analysis have continued, and sample results for another cross stream plane are presented. Available data include all mean velocity components, second order mean products of turbulent fluctuations, and third order mean products. Implementation of a faster data logging system was accomplished.
NASA Astrophysics Data System (ADS)
Dong, Da; Lu, Yang; Yuan, Yueming; Fan, Xuejun
2018-06-01
An experimental facility was designed to simulate the heat exchange between the hot gas and the fuel-cooled wall in a scramjet combustor. Thermal radiation from an electrically heated graphite plate is employed to unilaterally heat up a multi-channeled cooling plate. A maximum heat flux of over 0.8 MW/m2 was achieved for an effective heating area up to 1000 mm × 40 mm. Precise control of the back pressure of a coolant (up to 5 MPa) in a unique way was also demonstrated. With this facility, studies of flow and heat transfer in hydrocarbon-cooled structures can be performed under a well-controlled manner.
Global tectonic studies: Hotspots and anomalous topography
NASA Technical Reports Server (NTRS)
Burke, K.; Kidd, W. S. F.; Delong, S.; Thiessen, R. L.; Carosella, R.; Mcgetchin, T. R.
1979-01-01
Volcanic activity on Earth and its secular variations are compared with that on other terrestrial planets. Activity at divergent, transform, and convergent plate margins is described with particular emphasis on hot spots and flood basalts. The timing and causing of uplifting above 500 meters, which in not associated with either plate boundaries or the normal nonplate margin edges of continents is considered with particular focus on the Guyana Highlands in southern Venezuela and western British Guiana, and the Brazilian Highlands in the central, eastern, and southern parts of the country. The mode and mechanism of plateau uplifting and the re-elevation of old mountain belts and subsidence of intra-continental basins are also discussed.
The Lithospheric Geoid as a Constraint on Plate Dynamics
NASA Astrophysics Data System (ADS)
Richardson, R. M.; Coblentz, D. D.
2015-12-01
100 years after Wegener's pioneering work there is still considerable debate about the dynamics of present-day plate motions. A better understanding of present-day dynamics is key to a better understanding of the supercontinent cycle. The Earth's gravity field is one of the primary data sets to help constrain horizontal density contrasts, and hence plate dynamic forces. Previous work has shown that the global average for the geoid step up from old oceanic lithosphere across passive continental margins to stable continental lithosphere is about 6-9m, and the global average for the geoid anomaly associated with cooling oceanic lithosphere (the so-called "ridge push") is 10-12m. The ridge geoid anomaly corresponds to a net force of ~3x1012N/m (averaged over the thickness of the lithosphere) due to 'ridge push.' However, for individual continental margins and mid-ocean ridge systems, there is considerable variation in the geoid step and geoid anomaly and consequently the associated forces contributing to the stress field. We explore the variation in geoid step across passive continental margins looking for correlations with age of continental breakup (and hence place within the supercontinent cycle), hot spot tracks, continental plate velocities, long-wavelength geoid energy (that may be masking signal), and small scale convection. For mid-ocean ridges, we explore variations in geoid anomaly looking for correlations with plate spreading rates, hot spot tracks, long-wavelength geoid energy (that may be masking signal), and small scale convection. We use a band-pass spherical harmonic filter on the full geoid (e.g., EGM2008-WGS84, complete to spherical harmonic degree and order 2159) between orders 6 and 80. The evaluation of the role of spatial variations in the geoid gradient for cooling oceanic lithosphere and across the continental margin in the dynamics of the intraplate stress field requires high spatial resolution modeling. We perform a high resolution finite element analysis (~35,000 elements for a spatial resolution of approximately 50 km) for the North American plate, where previous lower resolution modeling has shown the importance of the lithospheric cooling (ridge push) force to model the broad scale stress patterns observed from the middle of the continent to the Mid-Atlantic ridge.
Use of Plasma Actuators as a Moving-Wake Generator
NASA Technical Reports Server (NTRS)
Corke, Thomas C.; Thomas, Flint O.; Klapetzky Michael J.
2007-01-01
The work documented in this report tests the concept of using plasma actuators as a simple and easy way to generate a simulated moving-wake and the disturbances associated with it in turbines. This wake is caused by the blades of the upstream stages of the turbine. Two types of devices, one constructed of arrays of NACA 0018 airfoils, and the one constructed of flat plates were studied. The airfoils or plates were equipped with surface mounted dielectric barrier discharge (DBD) plasma actuators, which were used to generate flow disturbances resembling moving-wakes. CTA hot-wire anemometry and flow visualization using a smoke-wire were used to investigate the wake independence at various spacings and downstream locations. The flat plates were found to produce better results than the airfoils in creating large velocity fluctuations in the free-stream flow. Different dielectric materials, plasma actuator locations, leading edge contours, angles of attack and plate spacings were investigated, some with positive results. The magnitudes of the velocity fluctuations were found to be comparable to existing mechanical moving-wake generators, thus proving the feasibility of using plasma actuators as a moving-wake generator.
Interaction of a Rectangular Jet with a Flat-Plate Placed Parallel to the Flow
NASA Technical Reports Server (NTRS)
Zaman, K. B. M. Q.; Brown, C. A.; Bridges, J. A.
2013-01-01
An experimental study is carried out addressing the flowfield and radiated noise from the interaction of a large aspect ratio rectangular jet with a flat plate placed parallel to but away from the direct path of the jet. Sound pressure level spectra exhibit an increase in the noise levels for both the 'reflected' and 'shielded' sides of the plate relative to the free-jet case. Detailed cross-sectional distributions of flowfield properties obtained by hot-wire anemometry are documented for a low subsonic condition. Corresponding mean Mach number distributions obtained by Pitot-probe surveys are presented for high subsonic conditions. In the latter flow regime and for certain relative locations of the plate, a flow resonance accompanied by audible tones is encountered. Under the resonant condition the jet cross-section experiences an 'axis-switching' and flow visualization indicates the presence of an organized 'vortex street'. The trends of the resonant frequency variation with flow parameters exhibit some similarities to, but also marked differences with, corresponding trends of the well-known edgetone phenomenon.
Numerical simulation of calcium sulfate (CaSO4) fouling in the plate heat exchanger
NASA Astrophysics Data System (ADS)
Xu, Zhiming; Zhao, Yu; Han, Zhimin; Wang, Jingtao
2018-07-01
Plate heat exchanger is a widely used apparatus in the industrial production processes. Through a numerical simulation method, this paper calculates the deposition rate of CaSO4 fouling on heat transfer surfaces of the plate heat exchanger under saturation in the bulk. The effects of CaSO4 concentration in the range 0.7 kg/m3 to 1.5 kg/m3, inlet flow velocity under turbulent flow, and the fluid's inlet temperature from 288 K to 328 K on the deposition rate, removal mass rate and fouling resistance are investigated. The simulation results are compared with the experimental results showing similar trend. The simulation results show that the concentration and the flow velocity affect significantly the fouling characteristics in the plate heat exchanger. The deposition mass rate, removal mass rate, and asymptotic value of fouling resistance all increase with the increase in CaSO4 concentration and the inlet temperature of the hot fluid, while the asymptotic value of fouling resistance decreases with the increasing of inlet flow velocity. The influence of the inlet temperature of cold fluid may be negligible.
NASA Astrophysics Data System (ADS)
Van Kranendonk, M. J.
2012-04-01
Over 4.5 billion years, Earth has evolved from a molten ball to a cooler planet with large continental plates, but how and when continents grew and plate tectonics started remain poorly understood. In this paper, I review the evidence that 3.5-3.2 Ga continental nuclei of the Pilbara (Australia) and Kaapvaal (southern Africa) cratons formed as thick volcanic plateaux over hot, upwelling mantle and survived due to contemporaneous development of highly depleted, buoyant, unsubductable mantle roots. This type of crust is distinct from, but complimentary to, high-grade gneiss terranes, as exemplified by the North Atlantic Craton of West Greenland, which formed through subduction-accretion tectonics on what is envisaged as a vigorously convecting early Earth with small plates. Thus, it is proposed that two types of crust formed on early Earth, in much the same way as in modern Earth, but with distinct differences resulting from a hotter Archean mantle. Volcanic plateaux provided a variety of stable habitats for early life, including chemical nutrient rich, shallow-water hydrothermal systems and shallow marine carbonate platforms.
Hot Spots and Mantle Plumes: A Window Into the Deep Earth and a Lesson on How Science Really Works
NASA Astrophysics Data System (ADS)
Caplan-Auerbach, J.
2010-12-01
Despite years of discussion, debate and controversy over the causes of ocean island volcanism, most students simply learn that such features form from fixed plumes of hot material rising from the core mantle boundary. Although we know that the Hawaiian plume exhibited substantial southward motion, most introductory geology textbooks still report that hot spots are fixed and that the Hawaiian-Emperor bend reflects a change in plate motion. That mantle plumes are the focus of significant controversy within the scientific community is rarely, if ever, discussed, and alternative models for the formation of intraplate volcanoes are ignored. Students may thus complete their studies without learning about the dynamic debate focused on the existence and formation of mantle plumes. This issue represents an opportunity for students to see how science really works, how new models are constructed, and what distinguishes a hypothesis from a theory. The culminating project in Western Washington University’s Introduction to Geophysics class, a course required for the BS degree in geology, focuses on the hot spot and mantle plume debate. For the first nine weeks of the quarter students learn about general topics in geophysics including plate tectonics, magnetism, seismology, gravity and heat flow. At the end of the course, students break into small research groups with the goal of investigating how geophysics may be used to address three questions: (1) Do ocean island volcanoes form from mantle plumes? (2) Are “hot spots” actually hot? (3) Are hot spots stationary? Each group examines how these questions may be addressed using a specific geophysical tool. In addition to the five topics described above, a sixth group investigates the question of “if not hot spots/mantle plumes, how do ocean island volcanoes form?” Students read the current literature on the topic and present their results to their classmates. Presentations focus on topics such as the use of seismic tomography to image deep plumes, the use of magnetic data to determine plume paleolatitude, and the search for heat flow anomalies near hot spots. On the final day of the class students revisit the three questions presented above and discuss whether their thoughts on the topic have changed as a result of studying the geophysics. Finally, the class discusses the issue in terms of Thomas Kuhn’s phases of scientific study, considering whether or not the mantle plumes paradigm is in crisis. As evidenced by comments in student course evaluations, the project is very popular and students appreciate the opportunity to investigate a modern scientific controversy. The project not only helps students learn how geophysics may be used to study the deep earth, it familiarizes them with current scientific literature, and perhaps most importantly, it allows them to learn about and engage in a critical scientific debate.
Qi, Shize; Liu, Xuezhu; Ford, Sean; Barrows, James; Thomas, Gloria; Kelly, Kevin; McCandless, Andrew; Lian, Kun; Goettert, Jost; Soper, Steven A
2002-05-01
High-aspect-ratio microstructures have been prepared using hot-embossing techniques in poly(methyl methacrylate) (PMMA) from Ni-based molding dies prepared using LIGA (Lithographie, Galvanoformung, Abformung). Due to the small amount of mask undercutting associated with X-ray lithography and the high energy X-ray beam used during photoresist patterning, deep structures with sharp and smooth sidewalls have been prepared. The Ni-electroforms produced devices with minimal replication errors using hot-embossing at a turn around time of approximately 5 min per device. In addition, several different polymers (with different glass transition temperatures) could be effectively molded with these Ni-electroforms and many devices (>300) molded with the same master without any noticeable degradation. The PMMA devices consisted of deep and narrow channels for insertion of a capillary for the automated electrokinetic loading of sample into the microfluidic device and also, a pair of optical fibers for shuttling laser light to the detection zone and collecting the resulting emission for fluorescence analysis. Electrophoretic separations of double-stranded DNA ladders Phi X174 digested with Hae III) were performed with fluorescence detection accomplished using near-IR excitation. It was found that the narrow width of the channels did not contribute significantly to electrophoretic zone broadening and the plate numbers generated in the extended length separation channel allowed sorting of the 271/281 base pair fragments associated with this sizing ladder when electrophoresed in methylcellulose entangled polymer solutions. The dual fiber detector produced sub-attomole detection limits with the entire detector, including laser source, electronics and photon transducer, situated in a single box measuring 3'' x 10" x 14".
DOE Office of Scientific and Technical Information (OSTI.GOV)
Isachsen, Y.W.
1978-09-27
Two areas in New York State were studied in terms of possible long range potential for geothermal energy: the Adirondack Mountains which are undergoing contemporary doming, and an anomalous circular feature centered on Panther Mountain in the Catskill Mountains. The Adirondack Mountains constitute an anomalously large, domical uplift on the Appalachian foreland. The domical configuration of the area undergoing uplift, combined with subsidence at the northeastern perimeter of the dome, argues for a geothermal rather than glacioisostatic origin. A contemporary hot spot near the crust-mantle boundary is proposed as the mechanism of doming, based on analogy with uplifts of similarmore » dimensions elsewhere in the world, some of which have associated Tertiary volcanics. The lack of thermal springs in the area, or high heat flow in drill holes up to 370 m deep, indicates that the front of the inferred thermal pulse must be at some depth greater than 1 km. From isopach maps by Rickard (1969, 1973), it is clear that the present Adirondack dome did not come into existence until sometime after Late Devonian time. Strata younger than this are not present to provide further time stratigraphic refinement of this lower limit. However, the consequent radial drainage pattern in the Adirondacks suggests that the dome is a relatively young tectonic feature. Using arguments based on fixed hot spots in central Africa, and the movement of North American plate, Kevin Burke (Appendix I) suggests that the uplift may be less than 4 m.y. old.The other area of interest, the Panther Mountain circular feature in the Catskill Mountains, was studied using photogeology, gravity and magnetic profiling, gravity modeling, conventional field methods, and local shallow seismic refraction profiling.« less
Whole planet coupling between climate, mantle, and core: Implications for rocky planet evolution
NASA Astrophysics Data System (ADS)
Foley, Bradford J.; Driscoll, Peter E.
2016-05-01
Earth's climate, mantle, and core interact over geologic time scales. Climate influences whether plate tectonics can take place on a planet, with cool climates being favorable for plate tectonics because they enhance stresses in the lithosphere, suppress plate boundary annealing, and promote hydration and weakening of the lithosphere. Plate tectonics plays a vital role in the long-term carbon cycle, which helps to maintain a temperate climate. Plate tectonics provides long-term cooling of the core, which is vital for generating a magnetic field, and the magnetic field is capable of shielding atmospheric volatiles from the solar wind. Coupling between climate, mantle, and core can potentially explain the divergent evolution of Earth and Venus. As Venus lies too close to the sun for liquid water to exist, there is no long-term carbon cycle and thus an extremely hot climate. Therefore, plate tectonics cannot operate and a long-lived core dynamo cannot be sustained due to insufficient core cooling. On planets within the habitable zone where liquid water is possible, a wide range of evolutionary scenarios can take place depending on initial atmospheric composition, bulk volatile content, or the timing of when plate tectonics initiates, among other factors. Many of these evolutionary trajectories would render the planet uninhabitable. However, there is still significant uncertainty over the nature of the coupling between climate, mantle, and core. Future work is needed to constrain potential evolutionary scenarios and the likelihood of an Earth-like evolution.
Influence of some design parameters on the thermal performance of domestic refrigerator appliances
NASA Astrophysics Data System (ADS)
Rebora, Alessandro; Senarega, Maurizio; Tagliafico, Luca A.
2006-07-01
This paper presents a thermal study on chest-freezers, the small refrigerators used in domestic and supermarket applications. A thermal and energy model of a particular kind of these refrigerators, the “hot-wall” (or “skin condenser”) refrigerator, is developed and used to perform sensitivity and design optimisation analysis for given working temperatures and useful volume of the refrigerated cell. A finite-element heat transfer model of the refrigerator box is coupled to the complete thermodynamic model of the refrigerating plant, including real working conditions (compressor efficiency, friction pressure losses and so on). A sensitivity study of the main design parameters affecting the global refrigerator performance has been developed (for fixed working temperatures) with reference to the thickness of the metallic plates, to the evaporator and condenser tube diameters and to the evaporator tube pitch (with fixed evaporator-to-condenser tube pitch ratio). The results obtained show that the proposed sensitivity analysis can yield quite reliable results (in comparison with much more complex, albeit more accurate mathematical optimisation algorithms) using small computational resources. The great importance of 2-D heat conduction in the metallic plates is shown, evidencing how the plate thickness and the evaporator and condenser tube diameters affect the global performance of the system according to the well-known “fin efficiency” effect. The influence of the evaporator and condenser tube diameters on the friction pressure losses is also outlined. Some practical suggestions are made in conclusion, regarding the criteria which should be adopted in the thermal design of a hot-wall refrigerator.
Pn tomography with Moho depth correction from eastern Europe to western China
NASA Astrophysics Data System (ADS)
Lü, Yan; Ni, Sidao; Chen, Ling; Chen, Qi-Fu
2017-02-01
We proposed a modified Pn velocity and anisotropy tomography method by considering the Moho depth variations using the Crust 1.0 model and obtained high-resolution images of the uppermost mantle Pn velocity and anisotropy structure from eastern Europe to western China. The tomography results indicate that the average Pn velocities are approximately 8.0 and 8.1 km/s under the western and eastern parts of the study area, respectively, with maximum velocity perturbations of 3%-4%. We observed high Pn velocities under the Adriatic Sea, Black Sea, Caspian Sea, Arabian Plate, Indian Plate, and in the Tarim and Sichuan Basins but low Pn velocities under the Apennine Peninsula, Dead Sea fault zone, Anatolia, Caucasus, Iranian Plateau, Hindu Kush, and in the Yunnan and Myanmar regions. Generally, regions with stable structures and low lithospheric temperatures exhibit high Pn velocities. Low Pn velocities provide evidence for the upwelling of hot material, which is associated with plate subduction and continental collision processes. Our Pn velocity and anisotropy imaging results indicate that the Adriatic microplate dives to the east and west, the hot material upwelling caused by subduction beneath the Tibetan Plateau is not as significant as that in the Caucasus and Myanmar regions, the lithosphere exhibits coupled rotational movement around the Eastern Himalayan syntaxes, and the areas to the north and south of 26°N in the Yunnan region are affected by different geodynamic processes. Our newly captured images of the uppermost mantle velocity and anisotropy structure provide further information about continental collision processes and associated dynamic mechanisms.
NASA Astrophysics Data System (ADS)
Lücke, O. H.; Arroyo, I. G.
2015-07-01
The eastern part of the oceanic Cocos Plate presents a heterogeneous crustal structure due to diverse origins and ages as well as plate-hot spot interactions which originated the Cocos Ridge, a structure that converges with the Caribbean Plate in southeastern Costa Rica. The complex structure of the oceanic plate directly influences the dynamics and geometry of the subduction zone along the Middle American Trench. In this paper an integrated interpretation of the slab geometry is presented based on three-dimensional density modeling of combined satellite and surface gravity data, constrained by available geophysical and geological data and seismological information obtained from local networks. The results show the continuation of steep subduction geometry from the Nicaraguan margin into Northwestern Costa Rica, followed by a moderate dipping slab under the Central Cordillera toward the end of the Central American Volcanic Arc. To the southeast end of the volcanic arc, our preferred model shows a steep, coherent slab that extends up to the landward projection of the Panama Fracture Zone. Overall, a gradual change in the depth of the intraplate seismicity is observed, reaching 220 km in the northwestern part, and becoming progressively shallower toward the southeast, where it reaches a terminal depth of 75 km. The changes in the terminal depth of the observed seismicity correlate with the increased density in the modeled slab. The absence of intermediate depth intraplate seismicity in the southeastern section and the higher densities for the subducted slab in this area, support a model in which dehydration reactions in the subducted slab cease at a shallower depth, originating an anhydrous and thus aseismic slab.
NASA Astrophysics Data System (ADS)
Lücke, O. H.; Arroyo, I. G.
2015-10-01
The eastern part of the oceanic Cocos Plate presents a heterogeneous crustal structure due to diverse origins and ages as well as plate-hot spot interactions which originated the Cocos Ridge, a structure that converges with the Caribbean Plate in southeastern Costa Rica. The complex structure of the oceanic plate directly influences the dynamics and geometry of the subduction zone along the Middle American Trench. In this paper an integrated interpretation of the slab geometry in Costa Rica is presented based on 3-D density modeling of combined satellite and surface gravity data, constrained by available geophysical and geological data and seismological information obtained from local networks. The results show the continuation of steep subduction geometry from the Nicaraguan margin into northwestern Costa Rica, followed by a moderate dipping slab under the Central Cordillera toward the end of the Central American Volcanic Arc. Contrary to commonly assumed, to the southeast end of the volcanic arc, our preferred model shows a steep, coherent slab that extends up to the landward projection of the Panama Fracture Zone. Overall, a gradual change in the depth of the intraplate seismicity is observed, reaching 220 km in the northwestern part, and becoming progressively shallower toward the southeast, where it reaches a maximum depth of 75 km. The changes in the terminal depth of the observed seismicity correlate with the increased density in the modeled slab. The absence of intermediate depth (> 75 km) intraplate seismicity in the southeastern section and the higher densities for the subducted slab in this area, support a model in which dehydration reactions in the subducted slab cease at a shallower depth, originating an anhydrous and thus aseismic slab.
Self-Propelled Hovercraft Based on Cold Leidenfrost Phenomenon
Shi, Meng; Ji, Xing; Feng, Shangsheng; Yang, Qingzhen; Lu, Tian Jian; Xu, Feng
2016-01-01
The Leidenfrost phenomenon of liquid droplets levitating and dancing when placed upon a hot plate due to propulsion of evaporative vapor has been extended to many self-propelled circumstances. However, such self-propelled Leidenfrost devices commonly need a high temperature for evaporation and a structured solid substrate for directional movements. Here we observed a “cold Leidenfrost phenomenon” when placing a dry ice device on the surface of room temperature water, based on which we developed a controllable self-propelled dry ice hovercraft. Due to the sublimated vapor, the hovercraft could float on water and move in a programmable manner through designed structures. As demonstrations, we showed that the hovercraft could be used as a cargo ship or a petroleum contamination collector without consuming external power. This phenomenon enables a novel way to utilize programmable self-propelled devices on top of room temperature water, holding great potential for applications in energy, chemical engineering and biology. PMID:27338595
Self-Propelled Hovercraft Based on Cold Leidenfrost Phenomenon.
Shi, Meng; Ji, Xing; Feng, Shangsheng; Yang, Qingzhen; Lu, Tian Jian; Xu, Feng
2016-06-24
The Leidenfrost phenomenon of liquid droplets levitating and dancing when placed upon a hot plate due to propulsion of evaporative vapor has been extended to many self-propelled circumstances. However, such self-propelled Leidenfrost devices commonly need a high temperature for evaporation and a structured solid substrate for directional movements. Here we observed a "cold Leidenfrost phenomenon" when placing a dry ice device on the surface of room temperature water, based on which we developed a controllable self-propelled dry ice hovercraft. Due to the sublimated vapor, the hovercraft could float on water and move in a programmable manner through designed structures. As demonstrations, we showed that the hovercraft could be used as a cargo ship or a petroleum contamination collector without consuming external power. This phenomenon enables a novel way to utilize programmable self-propelled devices on top of room temperature water, holding great potential for applications in energy, chemical engineering and biology.
Solar-heating and cooling system design package
NASA Technical Reports Server (NTRS)
1980-01-01
Package of information includes design data, performance specifications, drawings, hazard analysis, and spare parts list for commercially produced system installed in single-family dwelling in Akron, Ohio. System uses air flat-plate collectors, 12000 kg rock storage and backup heat pump. Solar portion requires 0.7 kW, and provides 35% of average total heating load including hot water. Information aids persons considering installing solar home-heating systems.
Cooking with the Sun. How To Build and Use Solar Cookers.
ERIC Educational Resources Information Center
Halacy, Beth; Halacy, Dan
For those working with solar energy and/or conservation and the careful use of resources, constructing a solar oven can be a fun and useful activity. This book describes the construction and use of solar ovens for cooking. Construction details are provided for two inexpensive solar ovens and a reflector hot plate that can then be used to cook 100…
Solar space and water heating system at Stanford University, Central Food Services Building
NASA Astrophysics Data System (ADS)
1980-05-01
This active hydronic domestic hot water and space heating system was 840 sq ft of single-glazed, liquid, flat plate collectors and 1550 gal heat storage tanks. The following are discussed: energy conservation, design philosophy, operation, acceptance testing, performance data, collector selection, bidding, costs, economics, problems, and recommendations. An operation and maintenance manual and as-built drawings are included in appendices.
Solar-heated and cooled savings and loan building-1-Leavenworth, Kanasas
NASA Technical Reports Server (NTRS)
1981-01-01
Report describes heating and cooling system which furnishes 90 percent of annual heating load, 70 percent of cooling load, and all hot water for two-story building. Roof-mounted flat-plate collectors allow three distinct flow rates and are oriented south for optimum energy collection. Building contains fully automated temperature controls is divided into five temperature-load zones, each with independent heat pump.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sai K. Mylavarapu; Xiaodong Sun; Richard E. Glosup
In high-temperature gas-cooled reactors, such as a very high temperature reactor (VHTR), an intermediate heat exchanger (IHX) is required to efficiently transfer the core thermal output to a secondary fluid for electricity generation with an indirect power cycle and/or process heat applications. Currently, there is no proven high-temperature (750–800 °C or higher) compact heat exchanger technology for high-temperature reactor design concepts. In this study, printed circuit heat exchanger (PCHE), a potential IHX concept for high-temperature applications, has been investigated for their heat transfer and pressure drop characteristics under high operating temperatures and pressures. Two PCHEs, each having 10 hot andmore » 10 cold plates with 12 channels (semicircular cross-section) in each plate are fabricated using Alloy 617 plates and tested for their performance in a high-temperature helium test facility (HTHF). The PCHE inlet temperature and pressure were varied from 85 to 390 °C/1.0–2.7 MPa for the cold side and 208–790 °C/1.0–2.7 MPa for the hot side, respectively, while the mass flow rate of helium was varied from 15 to 49 kg/h. This range of mass flow rates corresponds to PCHE channel Reynolds numbers of 950 to 4100 for the cold side and 900 to 3900 for the hot side (corresponding to the laminar and laminar-to-turbulent transition flow regimes). The obtained experimental data have been analyzed for the pressure drop and heat transfer characteristics of the heat transfer surface of the PCHEs and compared with the available models and correlations in the literature. In addition, a numerical treatment of hydrodynamically developing and hydrodynamically fully-developed laminar flow through a semicircular duct is presented. Relations developed for determining the hydrodynamic entrance length in a semicircular duct and the friction factor (or pressure drop) in the hydrodynamic entry length region for laminar flow through a semicircular duct are given. Various hydrodynamic entrance region parameters, such as incremental pressure drop number, apparent Fanning friction factor, and hydrodynamic entrance length in a semicircular duct have been numerically estimated.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Al-Meer, S. H.; Amr, M. A.; Helal, A.I.
Because of the very low level of {sup 90}Sr in the environmental soil samples and its determination by beta counting may take several weeks, we developed a procedure for ultra-trace determination of {sup 90}Sr using collision reaction cell-inductively coupled plasma tandem mass spectrometry (CRC-ICP-MS/MS, Agilent 8800). Soil samples were dried at 105 deg. C and then heated in a furnace at 550 deg. C to remove any organics present. 500 g of each soil samples were aliquoted into 2000 ml glass beakers. Each Soils samples were soaked in 2 ppm Sr solution carrier to allow determination of chemical yield. Themore » solid to liquid ratio was 1:1. Finally the soil samples were dried at 105 deg. C. Five hundred milliliters concentrated nitric acid and 250 ml hydrochloric acid volumes were added on 500 g soil samples. The samples were digested on hot plate at 80 deg. C to prevent spraying with continuous manual mixing. The leachate solution was separated. The solids were rinsed with 500 ml deionized water, warmed on a hot plate and the leachate plus previous leachate were filtered and the total volume was reduced to 500 ml by evaporation. Final leachate volume was transferred to a centrifuge tubes. The centrifuge tubes were centrifuged at 3,500 rpm for 10 min. The leachate was transferred to a 1 L beaker and heated on a hot plate to evaporate the leachate to dryness. The reside was re-dissolved in 100 ml of 2% HNO{sub 3} and reduced by evaporation to 10 mL. The solution was measured directly by CRC-ICP-MS/MS by setting the first quadruple analyzer to m/z 90 and introducing oxygen gas into the reaction cell for elimination isobar interference from zirconium-90. The method was validated by measurements of standard reference materials and applied on environmental soil samples. The overall time requirement for the measurement of strontium-90 by CRC-ICP-MS/MS is 2 days, significantly shorter than any radioanalytical protocol currently available. (authors)« less
Solar-energy-system performance evaluation: Honeywell OTS 44, Ocmulgee, Georgia
NASA Technical Reports Server (NTRS)
Mathur, A. K.; Pederson, S.
1982-01-01
The operation and technical performance of the solar operational test site (OTS 44) are described, based on data collected between April, 1981 and August, 1981. The following topics are discussed: system description, performance assessment, operating energy, energy savings, system maintenance, and conclusions. The solar energy system at OTS 44 is a hydronic heating and cooling system consisting of 5040 square feet of liquid cooled flat plate collectors; a 4000 gallon thermal storage tank; one 25 ton capacity organic Rankine cycle engine assisted water chillers; a forced draft cooling tower; and associated piping, pumps, valves, controls and heat rejection equipment. The solar system has eight basic modes of operation and several combination modes for providing space conditioning and hot water to the building. Data monitored during the 4 months of the operational test period found that the solar system collected 285 MMBtu of thermal energy of the total incident solar energy of 1040 MMBtu and provided 210 MMBtu for cooling and 10 MMBtu for heating and hot water. The net electrical energy saving due to the solar system was approximately 2600 kWh(e), and fossil energy saving was about 20 million Btu (MMBtu).
Advancements in ion beam figuring of very thin glass plates (Conference Presentation)
NASA Astrophysics Data System (ADS)
Civitani, M.; Ghigo, M.; Hołyszko, J.; Vecchi, G.; Basso, S.; Cotroneo, V.; DeRoo, C. T.; Schwartz, E. D.; Reid, P. B.
2017-09-01
The high-quality surface characteristics, both in terms of figure error and of micro-roughness, required on the mirrors of a high angular resolution x-ray telescope are challenging, but in principle well suited with a deterministic and non-contact process like the ion beam figuring. This process has been recently proven to be compatible even with very thin (thickness around 0.4mm) sheet of glasses (like D263 and Eagle). In the last decade, these types of glass have been investigated as substrates for hot slumping, with residual figure errors of hundreds of nanometres. In this view, the mirrors segments fabrication could be envisaged as a simple two phases process: a first replica step based on hot slumping (direct/indirect) followed by an ion beam figuring which can be considered as a post-fabrication correction method. The first ion beam figuring trials, realized on flat samples, showed that the micro-roughness is not damaged but a deeper analysis is necessary to characterize and eventually control/compensate the glass shape variations. In this paper, we present the advancements in the process definition, both on flat and slumped glass samples.
Research on Formation Mechanisms of Hot Dry Rock Resources in China
NASA Astrophysics Data System (ADS)
Wang, G.; Xi, Y.
2017-12-01
As an important geothermal resource, hot dry rock(HDR) reserves have been studied in many countries. HDR resources in China have huge capacity and have become one of the most important resources for the potential replacement of fossil fuels. However, HDR resources are difficult to develop and utilise. Technologies for use with HDR, such as high-temperature drilling, reservoir characterisation, reservoir fracturing, microseismic monitoring and high-temperature power stations, originate from the field of oil and drilling. Addressing how to take advantage of these developed technologies is a key factor in the development of HDR reserves. Based on the thermal crustal structure in China, HDR resources can be divided into four types: high radioactive heat production, sedimentary basin, modern volcano and the inner-plate active tectonic belt. The prospective regions of HDR resources are located in South Tibet, West Yunnan, the southeast coast of China, Bohai Rim, Songliao Basin and Guanzhong Basin. The related essential technologies are relatively mature, and the prospect of HDR power generation is promising. Therefore, analysing the formation mechanisms of HDR resources and promoting the transformation of technological achievements, large-scale development and the utilisation of HDR resources can be achieved in China.
Plate-Tectonic Circulation is Driven by Cooling From the Top and is Closed Within the Upper Mantle
NASA Astrophysics Data System (ADS)
Hamilton, W. B.
2001-12-01
Subduction drives plate tectonics and is due to cooling from the top: circulation is self-organized, and likely is closed above the discontinuity near 660 km. The contrary consensus that plate tectonics is driven by bottom heating and involves the entire mantle combines misunderstood kinematics with flawed concepts of through-the-mantle plumes and subduction. Plume conjecture came from the Emperor-Hawaii progression, the 45 Ma inflection in which was assumed to mark a 60-degree change in direction of that part of the Pacific plate over a fixed plume. Smooth spreading patterns around the east and south margin of the Pacific plate, and paleomagnetic data, disprove such a change. Speculations that plumes move, jump, etc. do not revive falsified conjecture. Geochemical distinctions between enriched island and depleted ridge basalts (which overlap) are expected products of normal upper-mantle processes, not plumes. MORB traverses solidus-T asthenosphere, whereas OIB zone-refines through subsolidus lithosphere and crust, crystallizing refractories to retain T of diminishing melt while assimilating and retaining fusibles. Tomographic inference of deep-mantle subduction is presented misleadingly and may reflect methodological and sampling artifacts (downward smearing, and concentration of recorded body waves in bundles within broad anomalies otherwise poorly sampled). Planetological and other data require hot Earth accretion, and thorough early fractionation, from material much more refractory than primitive meteorites, and are incompatible with the little-fractionated lower mantle postulated to permit whole-mantle circulation. The profound seismic discontinuity near 660 km is a thermodynamic and physical barrier to easy mass transfer in either direction. Refractory lower mantle convects slowly, perhaps in layers, and loses primarily original heat, whereas upper mantle churns rapidly, and the 660 decoupling boundary must have evolved into a compositional barrier also. Plate motions are driven by subduction, the passive falling away of oceanic lithosphere which is negatively buoyant because of top-down cooling. Slabs have top and bottom rolling hinges and sink subvertically (inclinations of slabs mark their positions, not trajectories) into the transition zone, where they are laid down on, and depress, the 660-km discontinuity. Rollback of upper hinges into subducting plates is required by plate behavior at all scales. That fronts of overriding plates advance at rollback velocity is required by common preservation atop their thin leading edges of little-deformed fore-arc basins. Convergence velocity also commonly equals rollback but is faster in some arcs. Steeply-sinking inclined slabs push sublithospheric upper mantle forward into the shrinking ocean from which they came, forcing seafloor spreading therein, and pull overriding plates behind them. Continental plates pass over sunken slabs like tanks above their basal treads, and material from, and displaced rearward by, sunken slabs is cycled into pull-apart oceans opening behind the continents, thus transferring mantle from shrinking to enlarging oceans. Hot mantle displaced above slabs enables backarc spreading. Spreading ridges, in both shrinking and enlarging oceans, are passive byproducts of subduction, and migrate because it is more energy efficient to process new asthenosphere than to get partial melt from increasingly distant sources. A plate-motion framework wherein hinges roll back, ridges migrate, Antarctica is approximately fixed, and intraplate deformation is integrated may approximate an absolute reference to sluggish lower mantle, whereas the hotspot frame is invalid, and the no-net-rotation frame minimizes trench and ridge motions.
Thermal modeling of a cryogenic turbopump for space shuttle applications.
NASA Technical Reports Server (NTRS)
Knowles, P. J.
1971-01-01
Thermal modeling of a cryogenic pump and a hot-gas turbine in a turbopump assembly proposed for the Space Shuttle is described in this paper. A model, developed by identifying the heat-transfer regimes and incorporating their dependencies into a turbopump system model, included heat transfer for two-phase cryogen, hot-gas (200 R) impingement on turbine blades, gas impingement on rotating disks and parallel plate fluid flow. The ?thermal analyzer' program employed to develop this model was the TRW Systems Improved Numerical Differencing Analyzer (SINDA). This program uses finite differencing with lumped parameter representation for each node. Also discussed are model development, simulations of turbopump startup/shutdown operations, and the effects of varying turbopump parameters on the thermal performance.
Experimental study on the monomer structure of solar semiconductor cold wall
NASA Astrophysics Data System (ADS)
Fu, Yuanyuan; Liu, Qiuxin; Chen, Tianshou
2018-06-01
In this paper, solar semiconductor cold wall structure was adopted in the net-zero energy buildings, NZEB for short. The heat transfer and refrigeration effect of the monomer structure of semiconductor cold wall were tested, we get that the monomer structure of semiconductor cold wall has certain cooling effect. However, the heat exchange effect is not good of the cold and hot aluminum plate only through natural convection and radiation heat transfer. It is necessary to further study the process of semiconductor refrigeration and heat transfer and the factors that affect the cooling effect. At the same time, it put forward a series of suggestions and improvement opinion for NZEB in hot summer and cold winter areas.
Patrick, Thomas E.; Goodwin, T. L.; Collins, J. A.; Wyche, R. C.; Love, B. E.
1972-01-01
A comparison of two types of scalders was conducted to determine their effectiveness in reducing bacterial contamination of poultry carcasses. A conventional hot-water scalder and a prototype model of a steam scalder were tested under commercial conditions. Total plate counts from steam-scalded birds were significantly lower than the counts of water-scalded birds immediately after scalding and again after picking. No differences in the two methods could be found after chilling. Coliform counts from steam-scalded birds were significantly lower than the counts from water-scalded birds immediately after scalding. No significant differences in coliform counts were detected when the two scald methods were compared after defeathering and chilling. PMID:4553146
Composite material reinforced with atomized quasicrystalline particles and method of making same
Biner, S.B.; Sordelet, D.J.; Lograsso, B.K.; Anderson, I.E.
1998-12-22
A composite material comprises an aluminum or aluminum alloy matrix having generally spherical, atomized quasicrystalline aluminum-transition metal alloy reinforcement particles disposed in the matrix to improve mechanical properties. A composite article can be made by consolidating generally spherical, atomized quasicrystalline aluminum-transition metal alloy particles and aluminum or aluminum alloy particles to form a body that is cold and/or hot reduced to form composite products, such as composite plate or sheet, with interfacial bonding between the quasicrystalline particles and the aluminum or aluminum alloy matrix without damage (e.g. cracking or shape change) of the reinforcement particles. The cold and/or hot worked composite exhibits substantially improved yield strength, tensile strength, Young`s modulus (stiffness). 3 figs.
Hu, Jing; Zhang, Xiaolong; Liu, Xiaoming; Tang, Jinshan
2015-06-01
Discovering hot regions in protein-protein interaction is important for drug and protein design, while experimental identification of hot regions is a time-consuming and labor-intensive effort; thus, the development of predictive models can be very helpful. In hot region prediction research, some models are based on structure information, and others are based on a protein interaction network. However, the prediction accuracy of these methods can still be improved. In this paper, a new method is proposed for hot region prediction, which combines density-based incremental clustering with feature-based classification. The method uses density-based incremental clustering to obtain rough hot regions, and uses feature-based classification to remove the non-hot spot residues from the rough hot regions. Experimental results show that the proposed method significantly improves the prediction performance of hot regions. Copyright © 2015 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
DeMets, Charles; Traylen, Stephen
2000-03-01
To better understand the influence of Rivera plate kinematics on the geodynamic evolution of western Mexico, we use more than 1400 crossings of seafloor spreading magnetic lineations along the Pacific-Rivera rise and northern Mathematician ridge to solve for rotations of the Rivera plate relative to the underlying mantle and the Pacific and North American plates at 14 times since 9.9 Ma. Our comparison of magnetic anomaly crossings from the undeformed Pacific plate to their counterparts on the Rivera plate indicates that significant areas of the Rivera plate have deformed since 9.9 Ma. Dextral shear along the southern edge of the plate from 3.3-2.2 Ma during a regional plate boundary reorganization deformed the Rivera plate farther into its interior than previously recognized. In addition, seafloor located north of two rupture zones within the Rivera plate sutured to North America after 1.5 Ma. Anomaly crossings from these two deformed regions thus cannot be used to reconstruct motion of the Rivera plate. Finite rotations that best reconstruct Pacific plate anomaly crossings onto their undeformed counterparts on the Rivera plate yield stage spreading rates that decrease gradually by 10% between 10 and 3.6 Ma, decrease rapidly by 20% after ˜3.6 Ma, and recover after 1 Ma. The slowdown in Pacific-Rivera seafloor spreading at 3.6 Ma coincided with the onset of dextral shear across the then-incipient southern boundary of the Rivera plate with the Pacific plate. The available evidence indicates that the Rivera plate has been an independent microplate since at least 10 Ma, contrary to published assertions that it fragmented from the Cocos plate at ˜5 Ma. Motion of the Rivera plate relative to North America has changed significantly since 10 Ma, in concert with significant changes in Pacific-Rivera motion. A significant and robust feature of Rivera-North America motion not previously recognized is the cessation of margin-normal convergence and thus subduction from 2.6 to 1.0 Ma along the entire plate boundary, followed by a resumption of trench-normal subduction along the southern half of the Rivera-North America plate boundary after 1.0 Ma. Motion of the Rivera plate relative to the underlying mantle since 10 Ma has oscillated between periods of landward motion and seaward motion. The evidence suggests that the torque exerted by slab pull on this young and hot oceanic plate is either minimal or is effectively counterbalanced by forces that resist its motion.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bachmann, B., E-mail: bachmann2@llnl.gov; Field, J.; Masters, N.
We have developed and fielded x-ray penumbral imaging on the National Ignition Facility in order to enable sub-10 μm resolution imaging of stagnated plasma cores (hot spots) of spherically shock compressed spheres and shell implosion targets. By utilizing circular tungsten and tantalum apertures with diameters ranging from 20 μm to 2 mm, in combination with image plate and gated x-ray detectors as well as imaging magnifications ranging from 4 to 64, we have demonstrated high-resolution imaging of hot spot plasmas at x-ray energies above 5 keV. Here we give an overview of the experimental design criteria involved and demonstrate themore » most relevant influences on the reconstruction of x-ray penumbral images, as well as mitigation strategies of image degrading effects like over-exposed pixels, artifacts, and photon limited source emission. We describe experimental results showing the advantages of x-ray penumbral imaging over conventional Fraunhofer and photon limited pinhole imaging and showcase how internal hot spot microstructures can be resolved.« less
Influence of hot spot features on the initiation characteristics of heterogeneous nitromethane
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dattelbaum, Dana M; Sheffield, Stephen A; Stahl, David B
2010-01-01
To gain insights into the critical hot spot features influencing energetic materials initiation characteristics, well-defined micron-scale particles have been intentionally introduced into the homogeneous explosive nitromethane (NM). Two types of potential hot spot origins have been examined - shock impedance mismatches using solid silica beads, and porosity using hollow microballoons - as well as their sizes and inter-particle separations. Here, we present the results of several series of gas gun-driven plate impact experiments on NM/particle mixtures with well-controlled shock inputs. Detailed insights into the nature of the reactive flow during the build-up to detonation have been obtained from the responsemore » of in-situ electromagnetic gauges, and the data have been used to establish Pop-plots (run-distance-to-detonation vs. shock input pressure) for the mixtures. Comparisons of sensitization effects and energy release characteristics relative to the initial shock front between the solid and hollow beads are presented.« less
Cálix-Lara, Thelma F; Kirsch, Katie R; Hardin, Margaret D; Castillo, Alejandro; Smith, Stephen B; Taylor, Thomas M
2015-06-01
Although studies have shown antimicrobial treatments consisting of hot water sprays alone or paired with lactic acid rinses are effective for reducing Escherichia coli O157:H7 loads on beef carcass surfaces, the mechanisms by which these interventions inactivate bacterial pathogens are still poorly understood. It was hypothesized that E. coli O157:H7 exposure to hot water in vitro at rising temperatures for longer time periods would result in increasing deterioration of bacterial outer membrane lipids, sensitizing the pathogen to subsequent lactic acid application. Cocktails of E. coli O157:H7 strains were subjected to hot water at 25 (control) 65, 75, or 85 °C incrementally up to 60 s, after which surviving cells were enumerated by plating. Formation of lipid hydroperoxides from bacterial membranes and cytoplasmic accumulation of L-lactic acid was quantified spectrophotometrically. Inactivation of E. coli O157:H7 proceeded in a hot water exposure duration- and temperature-dependent manner, with populations being reduced to nondetectable numbers following heating of cells in 85 °C water for 30 and 60 s (P < 0.05). Lipid hydroperoxide formation was not observed to be dependent upon increasing water temperature or exposure period. The data suggest that hot water application prior to organic acid application may function to increase the sensitivity of E. coli O157:H7 cells by degrading membrane lipids.
High Temperature Oxidation of Hot-Dip Aluminized T92 Steels
NASA Astrophysics Data System (ADS)
Abro, Muhammad Ali; Hahn, Junhee; Lee, Dong Bok
2018-03-01
The T92 steel plate was hot-dip aluminized, and oxidized in order to characterize the high-temperature oxidation behavior of hot-dip aluminized T92 steel. The coating consisted of Al-rich topcoat with scattered Al3Fe grains, Al3Fe-rich upper alloy layer with scattered (Al, Al5Fe2, AlFe)-grains, and Al5Fe2-rich lower alloy layer with scattered (Al5Fe2, AlFe)-grains. Oxidation at 800 °C for 20 h formed (α-Al2O3 scale)/(AlFe layer)/(AlFe3 layer)/(α-Fe(Al) layer), while oxidation at 900 °C for 20 h formed (α-Al2O3 scale plus some Fe2O3)/(AlFe layer)/(AlFe3 layer)/(α-Fe(Al) layer) from the surface. During oxidation, outward migration of all substrate elements, inward diffusion of oxygen, and back and forth diffusion of Al occurred according to concentration gradients. Also, diffusion transformed and broadened AlFe and AlFe3 layers dissolved with some oxygen and substrate alloying elements. Hot-dip aluminizing improved the high-temperature oxidation resistance of T92 steel through preferential oxidation of Al at the surface.
Energy efficiency of a solar domestic hot water system
NASA Astrophysics Data System (ADS)
Zukowski, Miroslaw
2017-11-01
The solar domestic hot water (SDHW) system located on the campus of Bialystok University of Technology is the object of the research described in the current paper. The solar thermal system is composed of 35 flat plate collectors, 21 evacuated tube collectors and eight hot water tanks with the capacity of 1 m3 of each. Solar facility is equipped with hardware for automatic data collection. Additionally, the weather station located on the roof of the building provides measurements of basic parameters of ambient air and solar radiation. The main objective of Regional Operational Program was the assessment of the effectiveness of this solar energy technology in the climatic conditions of the north-eastern Poland. Energy efficiency of SDHW system was defined in this research as the ratio between the useful heat energy supplied to the domestic hot water system and solar energy incident on the surface of solar panels. Heat loss from water storage tanks, and from the pipe network to the surrounding air, as well as the electrical energy consumed by the pumps have been included in the calculations. The paper presents the detailed results and conclusions obtained from this energy analysis.
High Temperature Oxidation of Hot-Dip Aluminized T92 Steels
NASA Astrophysics Data System (ADS)
Abro, Muhammad Ali; Hahn, Junhee; Lee, Dong Bok
2018-05-01
The T92 steel plate was hot-dip aluminized, and oxidized in order to characterize the high-temperature oxidation behavior of hot-dip aluminized T92 steel. The coating consisted of Al-rich topcoat with scattered Al3Fe grains, Al3Fe-rich upper alloy layer with scattered (Al, Al5Fe2, AlFe)-grains, and Al5Fe2-rich lower alloy layer with scattered (Al5Fe2, AlFe)-grains. Oxidation at 800 °C for 20 h formed (α-Al2O3 scale)/(AlFe layer)/(AlFe3 layer)/(α-Fe(Al) layer), while oxidation at 900 °C for 20 h formed (α-Al2O3 scale plus some Fe2O3)/(AlFe layer)/(AlFe3 layer)/(α-Fe(Al) layer) from the surface. During oxidation, outward migration of all substrate elements, inward diffusion of oxygen, and back and forth diffusion of Al occurred according to concentration gradients. Also, diffusion transformed and broadened AlFe and AlFe3 layers dissolved with some oxygen and substrate alloying elements. Hot-dip aluminizing improved the high-temperature oxidation resistance of T92 steel through preferential oxidation of Al at the surface.
A finite element solver for 3-D compressible viscous flows
NASA Technical Reports Server (NTRS)
Reddy, K. C.; Reddy, J. N.; Nayani, S.
1990-01-01
Computation of the flow field inside a space shuttle main engine (SSME) requires the application of state of the art computational fluid dynamic (CFD) technology. Several computer codes are under development to solve 3-D flow through the hot gas manifold. Some algorithms were designed to solve the unsteady compressible Navier-Stokes equations, either by implicit or explicit factorization methods, using several hundred or thousands of time steps to reach a steady state solution. A new iterative algorithm is being developed for the solution of the implicit finite element equations without assembling global matrices. It is an efficient iteration scheme based on a modified nonlinear Gauss-Seidel iteration with symmetric sweeps. The algorithm is analyzed for a model equation and is shown to be unconditionally stable. Results from a series of test problems are presented. The finite element code was tested for couette flow, which is flow under a pressure gradient between two parallel plates in relative motion. Another problem that was solved is viscous laminar flow over a flat plate. The general 3-D finite element code was used to compute the flow in an axisymmetric turnaround duct at low Mach numbers.
Long-Term Gravity Changes Caused By Crustal Movement in Tibet Region
NASA Astrophysics Data System (ADS)
Fang, J.
2014-12-01
The uplift process of the Tibetan Plateau and its mechanism has always been the research hot spot for geoscientists. In this paper, 11 years of time-variable gravity data from the Gravity Recovery and Climate Experiment (GRACE) newest Release 05 have been used to get the secular trends of gravity anomaly in CHINA and adjacent area by least square method. A reduction of hydrological signals from the detected integral secular trends using global hydrological models (Global Land Data Assimilation System, GLDAS and Climate Prediction Center, CPC) is attempted. The glacier model provided by Paulson is used to reduce the GIA(Glacial Isostatic Adjustment) effect. In addition, the scaling factor method is used to weaken the GRACE post-process errors. It turns out that a remarkable positive signal in the inner Tibetan Plateau, which is explained by a forward modeling with 3D rectangular prism based on the hypothesis of subduction of Indian plate beneath Eurasian plate. Bangong-Nujiang suture zone is used to divide the Tibetan Plateau into southern and northern parts, then we get the gravity anomaly rate of northern part +0.27, which is consistent with the GRACE result 0.35±0.13.
Update on slip and wear in multi-layer azimuth track systems
NASA Astrophysics Data System (ADS)
Juneja, Gunjeet; Kan, Frank W.; Antebi, Joseph
2006-06-01
Many antennas, such as the 100-m Green Bank Telescope, use a wheel-on-track systems in which the track segments consist of wear plates mounted on base plates. The wear plates are typically 2 to 3 inches thick and are case hardened or through hardened. The base plates are usually 3 to 4 times thicker than the wear plates and are not hardened. The wear plates are typically connected to the base plates using bolts. The base plates are supported on grout and anchored to the underlying concrete foundation. For some antennas, slip has been observed between the wear plate and base plate, and between the base plate and the grout, with the migration in the wheel rolling direction. In addition, there has been wear at the wear plate/base plate interface. This paper is an update on the evaluation of GBT track retrofit. The paper describes the use of three-dimensional non-linear finite element analyses to understand and evaluate the behavior of (1) the existing GBT wheel-on-track system with mitered joints, and (2) the various proposed modifications. The modifications include welding of the base plate joints, staggering of the wear plate joints from the base plate joints, changing thickness of the wear plate, and increasing bolt diameter and length. Parameters included in the evaluation were contact pressure, relative slip, wear at the wear plate/base plate interface, and bolt shears and moments.
Fan broadband interaction noise modeling using a low-order method
NASA Astrophysics Data System (ADS)
Grace, S. M.
2015-06-01
A low-order method for simulating broadband interaction noise downstream of the fan stage in a turbofan engine is explored in this paper. The particular noise source of interest is due to the interaction of the fan rotor wake with the fan exit guide vanes (FEGVs). The vanes are modeled as flat plates and the method utilizes strip theory relying on unsteady aerodynamic cascade theory at each strip. This paper shows predictions for 6 of the 9 cases from NASA's Source Diagnostic Test (SDT) and all 4 cases from the 2014 Fan Broadband Workshop Fundamental Case 2 (FC2). The turbulence in the rotor wake is taken from hot-wire data for the low speed SDT cases and the FC2 cases. Additionally, four different computational simulations of the rotor wake flow for all of the SDT rotor speeds have been used to determine the rotor wake turbulence parameters. Comparisons between predictions based on the different inputs highlight the possibility of a potential effect present in the hot-wire data for the SDT as well as the importance of accurately describing the turbulence length scale when using this model. The method produces accurate predictions of the spectral shape for all of the cases. It also predicts reasonably well all of the trends that can be considered based on the included cases such as vane geometry, vane count, turbulence level, and rotor speed.
Wang, Jian; Evans, Julian R G
2005-01-01
This paper describes the design, construction, and operation of the London University Search Instrument (LUSI) which was recently commissioned to create and test combinatorial libraries of ceramic compositions. The instrument uses commercially available powders, milled as necessary to create thick-film libraries by ink-jet printing. Multicomponent mixtures are prepared by well plate reformatting of ceramic inks. The library tiles are robotically loaded into a flatbed furnace and, when fired, transferred to a 2-axis high-resolution measurement table fitted with a hot plate where measurements of, for example, optical or electrical properties can be made. Data are transferred to a dedicated high-performance computer. The possibilities for remote interrogation and search steering are discussed.
Plate tectonics and hotspots: the third dimension.
Anderson, D L; Tanimoto, T; Zhang, Y S
1992-06-19
High-resolution seismic tomographic models of the upper mantle provide powerful new constraints on theories of plate tectonics and hotspots. Midocean ridges have extremely low seismic velocities to a depth of 100 kilometers. These low velocities imply partial melting. At greater depths, low-velocity and high-velocity anomalies record, respectively, previous positions of migrating ridges and trenches. Extensional, rifting, and hotspot regions have deep (> 200 kilometers) low-velocity anomalies. The upper mantle is characterized by vast domains of high temperature rather than small regions surrounding hotspots; the asthenosphere is not homogeneous or isothermal. Extensive magmatism requires a combination of hot upper mantle and suitable lithospheric conditions. High-velocity regions of the upper 200 kilometers of the mantle correlate with Archean cratons.
Concentrated solar power on demand demonstration: Construction and operation of a 25 kW prototype
NASA Astrophysics Data System (ADS)
Gil, Antoni; Codd, Daniel S.; Zhou, Lei; Trumper, David; Calvet, Nicolas; Slocum, Alexander H.
2016-05-01
Currently, the majority of concentrated solar power (CSP) plants built worldwide integrate thermal energy storage (TES) systems which enable dispatchable output and higher global plant efficiencies. TES systems are typically based on two tank molten salt technology which involves inherent drawbacks such as parasitic pumping losses and electric tracing of pipes, risk of solidification and high capital costs. The concept presented in this paper is based on a single tank where the concentrated sunlight is directly focused on the molten salt. Hot and cold volumes of salt (at 565 °C and 280 °C, respectively) are axially separated by an insulated divider plate which helps maintain the thermal gradient. The concept, based on existing technologies, seeks to avoid the listed drawbacks as well as reducing the final cost of the TES system. In order to demonstrate its feasibility, Masdar Institute (MI) and Massachusetts Institute of Technology are developing a 25 kW prototype to be tested in the Masdar Solar Platform beam down facility.
NASA Astrophysics Data System (ADS)
Steyn, Gideon; Vermeulen, Christiaan
2018-05-01
An experiment was designed to study the effect of the jet direction on convective heat-transfer coefficients in single-jet gas cooling of a small heated surface, such as typically induced by an accelerated ion beam on a thin foil or specimen. The hot spot was provided using a small electrically heated plate. Heat-transfer calculations were performed using simple empirical methods based on dimensional analysis as well as by means of an advanced computational fluid dynamics (CFD) code. The results provide an explanation for the observed turbulent cooling of a double-foil, Havar beam window with fast-flowing helium, located on a target station for radionuclide production with a 66 MeV proton beam at a cyclotron facility.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Srinivasan, Guruvenket; Sailer, Robert A.; Hoey, Justin
An apparatus and a non-vapor-pressure dependent method of chemical vapor deposition of Si based materials using direct injection of liquid hydrosilane(s) are presented. Liquid silane precursor solutions may also include metal, non-metal or metalloid dopants, nanomaterials and solvents. An illustrative apparatus has a precursor solution and carrier gas system, atomizer and deposit head with interior chamber and a hot plate supporting the substrate. Atomized liquid silane precursor solutions and carrier gas moves through a confined reaction zone that may be heated and the aerosol and vapor are deposited on a substrate to form a thin film. The substrate may bemore » heated prior to deposition. The deposited film may be processed further with thermal or laser processing.« less
Interference drag in a simulated wing-fuselage juncture
NASA Technical Reports Server (NTRS)
Kubendran, L. R.; Mcmahon, H.; Hubbartt, J. E.
1984-01-01
The interference drag in a wing fuselage juncture as simulated by a flat plate and a body of constant thickness having a 1.5:1 elliptical leading edge is evaluated experimentally. The experimental measurements consist of mean velocity data taken with a hot wire at a streamwise location corresponding to 16 body widths downstream of the body leading edge. From these data, the interference drag is determined by calculating the total momentum deficit (momentum area) in the juncture and also in the two dimensional turbulent boundary layers on the flat plate and body at locations sufficiently far from the juncture flow effect. The interference drag caused by the juncture drag as measured at this particular streamwise station is -3% of the total drag due to the flat plate and body boundary layers in isolation. If the body is considered to be a wing having a chord and span equal to 16 body widths, the interference drag due to the juncture is only -1% of the frictional drag of one surface of such a wing.
NASA Astrophysics Data System (ADS)
Foley, Bradford J.
2015-10-01
The long-term carbon cycle is vital for maintaining liquid water oceans on rocky planets due to the negative climate feedbacks involved in silicate weathering. Plate tectonics plays a crucial role in driving the long-term carbon cycle because it is responsible for CO2 degassing at ridges and arcs, the return of CO2 to the mantle through subduction, and supplying fresh, weatherable rock to the surface via uplift and orogeny. However, the presence of plate tectonics itself may depend on climate according to recent geodynamical studies showing that cool surface temperatures are important for maintaining vigorous plate tectonics. Using a simple carbon cycle model, I show that the negative climate feedbacks inherent in the long-term carbon cycle are uninhibited by climate's effect on plate tectonics. Furthermore, initial atmospheric CO2 conditions do not impact the final climate state reached when the carbon cycle comes to equilibrium, as long as liquid water is present and silicate weathering can occur. Thus an initially hot, CO2 rich atmosphere does not prevent the development of a temperate climate and plate tectonics on a planet. However, globally supply limited weathering does prevent the development of temperate climates on planets with small subaerial land areas and large total CO2 budgets because supply limited weathering lacks stabilizing climate feedbacks. Planets in the supply limited regime may become inhospitable for life and could experience significant water loss. Supply limited weathering is less likely on plate tectonic planets because plate tectonics promotes high erosion rates and thus a greater supply of bedrock to the surface.
Drug Delivery for Peripheral Nerve Regeneration
2015-11-01
components are shown in Figure 2. The solvent casting method was used for manufacturing devices, with the 75/25 PLGA pellets dissolved in acetone at a...bottom-up process that minimizes wrinkling of the sheet as it expands and contracts. Following 4 hours on a hot plate, the sheet was submerged into...glass transition temperature (40-60°C), eliminating many traditional sterilization methods like autoclaving. We evaluated deformation of the device
2016-12-01
2000 rpm to give a resist thickness of approximately 2 µm. Following resist exposure, a soft bake was performed at 95 °C for 60 s on a hot plate. The...resist was then exposed to UV light for 4.2 s while in contact with the mask. To perform image reversal, the exposed resist was baked at 105 °C for
Code of Federal Regulations, 2012 CFR
2012-04-01
... and 7 The dye is dissolved in glacial acetic and 8 N hydrochloric acids (1.33 : 1) and extracted with... required. (A) Glacial Acetic Acid (ACS grade). (B) Diethyl ether (Anhydrous)—Note and follow safety... acetic acid to the beaker and stir. Place the beaker on a hot plate and heat with stirring, until all of...
Code of Federal Regulations, 2011 CFR
2011-04-01
... and 7 The dye is dissolved in glacial acetic and 8 N hydrochloric acids (1.33 : 1) and extracted with... required. (A) Glacial Acetic Acid (ACS grade). (B) Diethyl ether (Anhydrous)—Note and follow safety... acetic acid to the beaker and stir. Place the beaker on a hot plate and heat with stirring, until all of...
Plate Waste in School Feeding Programs: Individual and Aggregate Measures
1979-12-01
entrees - the hot lunch or one of four sandwiches (submarine sandwich, peanut butter and jelly sandwich, peanut butter and marshmallow fluff sandwich...Butter and Marshmallow Fluff Sandwich 289 Peanut Butter and Jelly Sandwich 222 Submarine Sandwich, Roll 898 Bologna 301 Salami 435 Cheese 287 Lettuce...White Bread 162 Sliced Ham 375 Peanut Butter and Marshmallow Fluff Sandwich 162 Peanut Butter and Jelly Sandwich 148 Submarine Sandwich, Roll 1223
Mahdi, Rahman Ismael; Gan, W C; Abd Majid, W H
2014-10-14
Ferroelectric poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) copolymer 70/30 thin films are prepared by spin coating. The crystalline structure of these films is investigated by varying the annealing temperature from the ferroelectric phase to the paraelectric phase. A hot plate was used to produce a direct and an efficient annealing effect on the thin film. The dielectric, ferroelectric and pyroelectric properties of the P(VDF-TrFE) thin films are measured as a function of different annealing temperatures (80 to 140 °C). It was found that an annealing temperature of 100 °C (slightly above the Curie temperature, Tc) has induced a highly crystalline β phase with a rod-like crystal structure, as examined by X-ray. Such a crystal structure yields a high remanent polarization, Pr = 94 mC/m2, and pyroelectric constant, p = 24 μC/m2K. A higher annealing temperature exhibits an elongated needle-like crystal domain, resulting in a decrease in the crystalline structure and the functional electrical properties. This study revealed that highly crystalline P(VDF-TrFE) thin films could be induced at 100 °C by annealing the thin film with a simple and cheap method.
NASA Astrophysics Data System (ADS)
Priego Quesada, Jose Ignacio; Martínez Guillamón, Natividad; Cibrián Ortiz de Anda, Rosa M.a.; Psikuta, Agnes; Annaheim, Simon; Rossi, René Michel; Corberán Salvador, José Miguel; Pérez-Soriano, Pedro; Salvador Palmer, Rosario
2015-09-01
The aim of the present study was to compare infrared thermography and thermal contact sensors for measuring skin temperature during cycling in a moderate environment. Fourteen cyclists performed a 45-min cycling test at 50% of peak power output. Skin temperatures were simultaneously recorded by infrared thermography and thermal contact sensors before and immediately after cycling activity as well as after 10 min cooling-down, representing different skin wetness and blood perfusion states. Additionally, surface temperature during well controlled dry and wet heat exchange (avoiding thermoregulatory responses) using a hot plate system was assessed by infrared thermography and thermal contact sensors. In human trials, the inter-method correlation coefficient was high when measured before cycling (r = 0.92) whereas it was reduced immediately after the cycling (r = 0.82) and after the cooling-down phase (r = 0.59). Immediately after cycling, infrared thermography provided lower temperature values than thermal contact sensors whereas it presented higher temperatures after the cooling-down phase. Comparable results as in human trials were observed for hot plate tests in dry and wet states. Results support the application of infrared thermography for measuring skin temperature in exercise scenarios where perspiration does not form a water film.
Nishiyama, Yumi; Moriyasu, Masataka; Ichimaru, Momoyo; Iwasa, Kinuko; Kato, Atsushi; Mathenge, Simon G; Chalo Mutiso, Patrick B; Juma, Francis D
2010-01-01
In the present study, we attempted to elucidate the antinociceptive activity of Xylopia parviflora bark using the acetic acid-induced writhing test, hot plate test, and formalin test in mice. The MeOH extract (100 and 200 mg/kg, administered intraperitoneally (i.p.)) had an antinociceptive effect demonstrated by its inhibitory effects on writhing number induced by acetic acid. Three alkaloidal fractions exhibited significant antinociceptive effects in three animal models; the chloroform-soluble fraction, including secondary and tertiary alkaloids, exhibited the strongest effect. This result supported its use in folk medicine as an analgesic agent. We tested the main alkaloids of these fractions for their antinociceptive effects to clarify the active components. (+)-Corytuberine (6.3 and 12.5 mg/kg, i.p.) showed very strong activity, had a significant antinociceptive effect in the acetic acid-induced writhing test (with 49.4 and 98.9% reduction of writhes), in the hot plate test, and in the formalin test (with 55.4 and 90.6% inhibition during the first phase, and 73.9 and 99.9% during the second phase, respectively). (+)-Glaucine (12.5 and 25 mg/kg, i.p.) showed strong activity in three animal models, too. The activity of these compounds was also observed following oral administration in the acetic acid-induced writhing test.
Almeida, Jackson R G S; Silva, Juliane C; Guimarães, Amanda L; Oliveira, Ana P; Souza, Grasielly R; Oliveira-Júnior, Raimundo G; Lima-Saraiva, Sarah R G; Barbosa-Filho, José M; Braz-Filho, Raimundo; Queiroz, Dinalva Brito; Botelho, Marco Antônio
2015-10-01
Lonchocarpus araripensis Benth. is largely distributed in the northeast region of Brazil. It is popularly known as 'sucupira'. Recent studies have shown that some species of Lonchocarpus have interesting pharmacological activities. In this study, we evaluated the antinociceptive effect of a flavone isolated from L. araripensis. The chemical examination resulted in the isolation of 3,6-dimethoxy-6″,6″-dimethyl-(7,8,2″,3″)-chromeneflavone (DDF). The structure of the compound was established by spectral analysis. Antinociceptive activity of DDF was evaluated by measuring nociception by acetic acid, formalin and hot plate tests. The rota rod test was used to evaluate motor coordination. The results demonstrated that DDF was able to prevent acetic-acid-writhing-induced nociception (p < 0.001) in mice. Furthermore, DDF produced a significant reduction of the nociceptive behaviour at the early and late phases of paw licking in the formalin test. Also, DDF produced an inhibition of the nociceptive behaviour during a hot-plate test. No alteration in motor coordination was observed. These results confirm the hypothesis that DDF reduces the nociceptive behaviour in mice, probably through central mechanisms, but without compromising the motor coordination of animals. Copyright © 2015 John Wiley & Sons, Ltd.
Gajanan Khanage, Shantaram; Raju, Appala; Baban Mohite, Popat; Bhanudas Pandhare, Ramdas
2013-01-01
Purpose: In the present study in vivo analgesic activity of some previously synthesized 1,2,4-triazole derivatives containing pyrazole, tetrazole, isoxazole and pyrimidine ring have been evaluated. Methods: Acetic acid induced writhing method and Hot plate method has been described to study analgesic activity of some 1,2,4-triazole derivatives containing pyrazole, tetrazole, isoxazole and pyrimidine as a pharmacological active lead. Results: Thirty six different derivatives containing 1,2,4-triazole ring were subjected to study their in vivo analgesic activity. Chloro, nitro and methoxy, hydroxy and bromo substituted derivatives showed excellent analgesic activity and dimethylamino, furan and phenyl substituted derivatives showed moderate analgesic activity in both of the methods. Compounds IIIa, IIId, IIIf, IIIi, IIIj, IVa, IVb, IVd, IVf, IVh, IVj IV3a and IIj were found to be superior analgesic agents after screening by Acetic acid induced writhing method. Compounds IIIb, IIId, IIIf, IIIh, IIIj, IVa, IVb, IVd, IVf, IVh, IVi, IV3c, IV3e and IIj were showed analgesic potential after screening of Hot plate method. Conclusion: All tested compounds containing 1,2,4-triazole were found to be promising analgesic agents, for this activity pyrazole, tetrazole, isoxazole and pyrimidine leads might be supported. PMID:24312806
Investigation of the hard x-ray background in backlit pinhole imagers.
Fein, J R; Peebles, J L; Keiter, P A; Holloway, J P; Klein, S R; Kuranz, C C; Manuel, M J-E; Drake, R P
2014-11-01
Hard x-rays from laser-produced hot electrons (>10 keV) in backlit pinhole imagers can give rise to a background signal that decreases signal dynamic range in radiographs. Consequently, significant uncertainties are introduced to the measured optical depth of imaged plasmas. Past experiments have demonstrated that hard x-rays are produced when hot electrons interact with the high-Z pinhole substrate used to collimate the softer He-α x-ray source. Results are presented from recent experiments performed on the OMEGA-60 laser to further study the production of hard x-rays in the pinhole substrate and how these x-rays contribute to the background signal in radiographs. Radiographic image plates measured hard x-rays from pinhole imagers with Mo, Sn, and Ta pinhole substrates. The variation in background signal between pinhole substrates provides evidence that much of this background comes from x-rays produced in the pinhole substrate itself. A Monte Carlo electron transport code was used to model x-ray production from hot electrons interacting in the pinhole substrate, as well as to model measurements of x-rays from the irradiated side of the targets, recorded by a bremsstrahlung x-ray spectrometer. Inconsistencies in inferred hot electron distributions between the different pinhole substrate materials demonstrate that additional sources of hot electrons beyond those modeled may produce hard x-rays in the pinhole substrate.
Investigation of the hard x-ray background in backlit pinhole imagers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fein, J. R., E-mail: jrfein@umich.edu; Holloway, J. P.; Peebles, J. L.
Hard x-rays from laser-produced hot electrons (>10 keV) in backlit pinhole imagers can give rise to a background signal that decreases signal dynamic range in radiographs. Consequently, significant uncertainties are introduced to the measured optical depth of imaged plasmas. Past experiments have demonstrated that hard x-rays are produced when hot electrons interact with the high-Z pinhole substrate used to collimate the softer He-α x-ray source. Results are presented from recent experiments performed on the OMEGA-60 laser to further study the production of hard x-rays in the pinhole substrate and how these x-rays contribute to the background signal in radiographs. Radiographicmore » image plates measured hard x-rays from pinhole imagers with Mo, Sn, and Ta pinhole substrates. The variation in background signal between pinhole substrates provides evidence that much of this background comes from x-rays produced in the pinhole substrate itself. A Monte Carlo electron transport code was used to model x-ray production from hot electrons interacting in the pinhole substrate, as well as to model measurements of x-rays from the irradiated side of the targets, recorded by a bremsstrahlung x-ray spectrometer. Inconsistencies in inferred hot electron distributions between the different pinhole substrate materials demonstrate that additional sources of hot electrons beyond those modeled may produce hard x-rays in the pinhole substrate.« less
NASA Astrophysics Data System (ADS)
Duan, Luanfang; Qi, Chonggang; Ling, Xiang; Peng, Hao
2018-03-01
In the present work, the contact heat transfer between the granular materials and heating plates inside plate rotary heat exchanger (PRHE) was investigated. The heat transfer coefficient is dominated by the contact heat transfer coefficient at hot wall surface of the heating plates and the heat penetration inside the solid bed. A plot scale PRHE with a diameter of Do = 273 mm and a length of L = 1000 mm has been established. Quartz sand with dp = 2 mm was employed as the experimental material. The operational parameters were in the range of ω = 1 - 8 rpm, and F = 15, 20, 25, 30%, and the effect of these parameters on the time-average contact heat transfer coefficient was analyzed. The time-average contact heat transfer coefficient increases with the increase of rotary speed, but decreases with the increase of the filling degree. The measured data of time-average heat transfer coefficients were compared with theoretical calculations from Schlünder's model, a good agreement between the measurements and the model could be achieved, especially at a lower rotary speed and filling degree level. The maximum deviation between the calculated data and the experimental data is approximate 10%.
NASA Astrophysics Data System (ADS)
Vidi, S.; Rausch, S.; Ebert, H. P.; Löhberg, A.; Petry, D.
2013-05-01
Measurements were done on a carbon fiber reinforced composite (CFC) sample tested for the space probe Bepi Colombo by using the guarded hot-plate (GHP) method. The values of interest were the thermal transmittance through the samples, (56.3 ± 3.6) W · m-2 · K-1, and the effective thermal conductivity (1.06 ± 0.07) W · m-1 · K-1. The samples consist of a light honeycomb core attached to thicker surface plates. Due to this construction, the effective thermal conductivity parallel to the face plates is higher than the effective thermal conductivity through the sample. This leads to lateral heat gains or losses during the GHP measurement, which in return can lead to erroneous results. Furthermore, due to the high rigidity of the CFC material, there will be high contact resistances between the samples and the GHP apparatus plates. The separation of these thermal contact resistances from the total measured thermal resistance is essential in order to achieve correct results. Good results were achieved using a special measurement setup and a lateral correction method designed to reduce errors due to lateral heat flows.
Seismogenesis of dual subduction beneath Kanto, central Japan controlled by fluid release.
Ji, Yingfeng; Yoshioka, Shoichi; Manea, Vlad C; Manea, Marina
2017-12-04
Dual subduction represents an unusual case of subduction where one oceanic plate subducts on top of another, creating a highly complex tectonic setting. Because of the complex interaction between the two subducted plates, the origin of seismicity in such region is still not fully understood. Here we investigate the thermal structure of dual subduction beneath Kanto, central Japan formed as a consequence of a unique case of triple trench junction. Using high-resolution three-dimensional thermo-mechanical models tailored for the specific dual subduction settings beneath Kanto, we show that, compared with single-plate subduction systems, subduction of double slabs produces a strong variation of mantle flow, thermal and fluid release pattern that strongly controls the regional seismicity distribution. Here the deepening of seismicity in the Pacific slab located under the Philippine Sea slab is explained by delaying at greater depths (~150 km depth) of the eclogitization front in this region. On the other hand, the shallower seismicity observed in the Philippine Sea slab is related to a young and warm plate subduction and probably to the presence of a hot mantle flow traveling underneath the slab and then moving upward on top of the slab.
Consequences of Rift Propagation for Spreading in Thick Oceanic Crust in Iceland
NASA Astrophysics Data System (ADS)
Karson, J. A.
2015-12-01
Iceland has long been considered a natural laboratory for processes related to seafloor spreading, including propagating rifts, migrating transforms and rotating microplates. The thick, hot, weak crust and subaerial processes of Iceland result in variations on the themes developed along more typical parts of the global MOR system. Compared to most other parts of the MOR, Icelandic rift zones and transform faults are wider and more complex. Rift zones are defined by overlapping arrays of volcanic/tectonic spreading segments as much as 50 km wide. The most active rift zones propagate N and S away from the Iceland hot spot causing migration of transform faults. A trail of crust deformed by bookshelf faulting forms in their wakes. Dead or dying transform strands are truncated along pseudofaults that define propagation rates close to the full spreading rate of ~20 mm/yr. Pseudofaults are blurred by spreading across wide rift zones and laterally extensive subaerial lava flows. Propagation, with decreasing spreading toward the propagator tips causes rotation of crustal blocks on both sides of the active rift zones. The blocks deform internally by the widespread reactivation of spreading-related faults and zones of weakness along dike margins. The sense of slip on these rift-parallel strike-slip faults is inconsistent with transform-fault deformation. These various deformation features as well as subaxial subsidence that accommodate the thickening of the volcanic upper crustal units are probably confined to the brittle, seismogenic, upper 10 km of the crust. At least beneath the active rift zones, the upper crust is probably decoupled from hot, mechanically weak middle and lower gabbroic crust resulting in a broad plate boundary zone between the diverging lithosphere plates. Similar processes may occur at other types of propagating spreading centers and magmatic rifts.
NASA Astrophysics Data System (ADS)
Sager, W. W.; Engfer, D.; Thoram, S.; Koppers, A. A. P.; Class, C.
2015-12-01
Walvis Ridge (WR) and Rio Grande Rise (RGR) are Cretaceous-Cenozoic large igneous provinces (LIPs) formed by the Tristan-Gough hot spot interacting with the Mid-Atlantic Ridge (MAR). Although hot spot-ridge interaction has long been considered a primary factor controlling WR-RGR morphology, details are fuzzy owing to sparse geophysical data. We examined tectonic fabric revealed in satellite altimetry-derived gravity data to infer details about RGR-WR evolution. Plate tectonic reconstructions indicate that the main RGR plateau and large N-S plateau in the eastern WR erupted at the same point at ~90 Ma. Over the next ~8 Myr, these conjunct LIPs formed a "V" shape with a basin in between. Curved fracture zones within the basin imply the two LIPs formed around a microplate. The prominent rift in the middle of RGR formed nearly perpendicular to the RGR-WR intersection, suggesting an extensional microplate boundary. Hot spot eruptions continued at the MAR, emplacing the eastern WR and two main RGR plateaus until ~60 Ma. During this period, the N-S trending Eastern Rio Grande Rise (ERGR) was erupted along the MAR. Both the ERGR and WR formed bathymetric lineaments parallel to seafloor fault fabric and were likely connected. This resulted in WR seamounts with a "tadpole" shape, the head being small to medium seamounts on the WR track and the tails being low, spreading-fabric-parallel ridges extending up to ~150 km northward. Similar, small seamounts are found in the contemporaneous ERGR. Another critical observation is that the WR-RGR formed at a large crustal discontinuity (~700 km at anomaly C33, ~84 Ma) at one or more fracture zone offsets. By late Cenozoic time (anomaly C5, ~10 Ma), the offset was reduced by half while several new fracture zones formed at the junction between RGR and WR. This implies a connection between ridge reorganization and RGR-WR volcanism that may have resulted from the fracture zones becoming oblique to the spreading direction as Euler poles for South America - Africa shifted. Finally, after ~60 Ma, volcanism emplaced seamounts mainly on the African plate and hot spot volcanism at the MAR was greatly reduced. Results from the present study augment recently published findings of a strong link between the formation of the RGR-WR LIP and spreading ridge tectonics.