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1

Heat transfer under heating of a local region of a large production area by gas infrared radiators  

NASA Astrophysics Data System (ADS)

This paper presents the results of a computational modeling of the processes of heat transfer in a region having the size of a local working zone and heated due to the energy input from gas infrared radiators. The regimes of turbulent natural conjugate convection with one boundary open for air have been investigated. The plane nonstationary problem has been solved from the viewpoint of the Navier-Stokes model for the gas and the heat conduction for solid walls.

Kuznetsov, G. V.; Kurilenko, N. I.; Maksimov, V. I.; Mamontov, G. Ya.; Nagornova, T. A.

2013-05-01

2

Nanoparticles heat through light localization.  

PubMed

Aqueous solutions containing light-absorbing nanoparticles have recently been shown to produce steam at high efficiencies upon solar illumination, even when the temperature of the bulk fluid volume remains far below its boiling point. Here we show that this phenomenon is due to a collective effect mediated by multiple light scattering from the dispersed nanoparticles. Randomly positioned nanoparticles that both scatter and absorb light are able to concentrate light energy into mesoscale volumes near the illuminated surface of the liquid. The resulting light absorption creates intense localized heating and efficient vaporization of the surrounding liquid. Light trapping-induced localized heating provides the mechanism for low-temperature light-induced steam generation and is consistent with classical heat transfer. PMID:24960442

Hogan, Nathaniel J; Urban, Alexander S; Ayala-Orozco, Ciceron; Pimpinelli, Alberto; Nordlander, Peter; Halas, Naomi J

2014-08-13

3

Biomass recycling heat technology and energy products  

NASA Astrophysics Data System (ADS)

Relevance is determined by necessity of utilizing of local low-grade fuels by energy equpment. Most widespread Tomsk oblast (Russian Federation region) low-grade fuels are described and listed. Capability of utilizing is analysed. Mass balances of heat-technology conversion materials and derived products are described. As a result, recycling capability of low-grade fuels in briquette fuel is appraised.

Tabakaev, R. B.; Gergelizhiu, P. S.; Kazakov, A. V.; Zavorin, A. S.

2014-10-01

4

Localized induction heating for wafer level packaging  

Microsoft Academic Search

Localized induction heating for wafer level packaging is discussed. This paper is to investigate the relationships between the geometry of solder loop and temperature distribution in induction heating. Using finite element method (FEM) and IR thermal imager, temperature distribution and variation are explored, which shows that the temperature on the solder loops is a function of the area and edge

Mingxiang Chen; Wenming Liu; Yanyan Xi; Changyong Lin; Sheng Liu

2009-01-01

5

Effects of local heating of the testes on the concentration of testosterone in jugular and testicular venous blood of rats and on testosterone production in vitro.  

PubMed

Heating both testes of rats to between 39 degrees C and 41 degrees C for 30 min was apparently without effect 21 days later, but heating to between 41.5 degrees C and 43 degrees C for 30 min resulted in a significant drop in testis weight accompanied by significant rises in the serum levels of LH and FSH. There were no changes in serum testosterone concentration in the peripheral circulation although there were increases in the concentration in testicular venous blood. The ability of the heated testis to secrete testosterone in vivo in response to maximal stimulation by hCG was reduced, as judged by testosterone levels in peripheral blood, while there was a supranormal increase in testosterone levels in testicular venous blood. Maximally stimulated testosterone production in vitro by the heated testis was supranormal whereas the basal production of testosterone per testis was not different from control values. Therefore, it appears that the testosterone produced by Leydig cells from heated testes may not be secreted as effectively as in normal testes. PMID:3128487

Galil, K A; Setchell, B P

1988-02-01

6

Compact Directional Microwave Antenna for Localized Heating  

NASA Technical Reports Server (NTRS)

A directional, catheter-sized cylindrical antenna has been developed for localized delivery of microwave radiation for heating (and thus killing) diseased tissue without excessively heating nearby healthy tissue. By "localized" is meant that the antenna radiates much more in a selected azimuthal direction than in the opposite radial direction, so that it heats tissue much more on one side than it does on the opposite side. This antenna can be inserted using either a catheter or a syringe. A 2.4-mm prototype was tested, although smaller antennas are possible. Prior compact, cylindrical antennas designed for therapeutic localized hyperthermia do not exhibit such directionality; that is, they radiate in approximately axisymmetric patterns. Prior directional antennas designed for the same purpose have been, variously, (1) too large to fit within catheters or (2) too large, after deployment from catheters, to fit within the confines of most human organs. In contrast, the present antenna offers a high degree of directionality and is compact enough to be useable as a catheter in some applications.

Fink, Patrick W.; Lin, Gregory Y.; Chu, Andrew W.; Dobbins, Justin A.; Arndt, G. Dickey; Ngo, Phong

2008-01-01

7

Implantable apparatus for localized heating of tissue  

DOEpatents

With the object of repetitively treating deep-seated, inoperable tumors by hyperthermia as well as locally heating other internal tissue masses repetitively, a receiving antenna, transmission line and electrode arrangement are implanted completely within the patient's body, with the receiving antenna just under the surface of the skin and with the electrode arrangement being located so as to most effectively heat the tissue to be treated. An external, transmitting antenna, driven by an external radio-frequency energy source, is closely coupled to the implanted receiving antenna so that the energy coupled across the air-skin interface provides electromagnetic energy suitable for heating the tissue in the vicinity of the implanted electrodes. The resulting increase in tissue temperature may be estimated by an indirect measurement of the decrease in tissue resistivity in the heat region. This change in resistivity appears as a change in the loading of the receiving antenna which can be measured by either determining the change in the phase relationship between the voltage and the current appearing on the transmitting antenna or by measuring the change in the magnitude of the impedance thereof. Optionally, multiple electrode arrays may be activated or inactivated by the application of magnetic fields to operate implanted magnetic reed swtiches. 5 figs.

Doss, J.D.

1985-05-20

8

Implantable apparatus for localized heating of tissue  

DOEpatents

With the object of repetitively treating deep-seated, inoperable tumors by hyperthermia as well as locally heating other internal tissue masses repetitively, a receiving antenna, transmission line, and electrode arrangment are implanted completely within the patient's body, with the receiving antenna just under the surface of the skin and with the electrode arrangement being located so as to most effectively heat the tissue to be treated. An external, transmitting antenna, driven by an external radio-frequency energy source, is closely coupled to the implanted receiving antenna so that the energy coupled across the air-skin interface provides electromagnetic energy suitable for heating the tissue in the vicinity of the implanted electrodes. The resulting increase in tissue temperature may be estimated by an indirect measurement of the decrease in tissue resistivity in the heated region. This change in resistivity appears as a change in the loading of the receiving antenna which can be measured by either determining the change in the phase relationship between the voltage and the current appearing on the transmitting antenna or by measuring the change in the magnitude of the impedance thereof. Optionally, multiple electrode arrays may be activated or inactivated by the application of magnetic fields to operate implanted magnetic reed switches.

Doss, James D. (Los Alamos, NM)

1987-01-01

9

Heat Production as a Tool in Geothermal Exploration  

NASA Astrophysics Data System (ADS)

Heat flow data (together with knowledge, or assumptions, of stratigraphy, thermal conductivity and heat production) provide the prime parameter for estimating the potential of geothermal resources. Unfortunately this information is expensive to obtain as it requires deep boreholes. Consequently it is sparse or lacking in areas not traditionally considered as having geothermal potential. New England (and most of the northeastern U.S.A.) is one such area. However, in the absence of volcano-derived hydrothermal activity with its attendant high heat flow, granitic plutons provide an alternative geothermal resource. Compared with other crustal rocks, granites contain higher concentrations of heat-producing elements (K, U, Th). Additionally, they are relatively homogeneous, compared to surrounding country rock, allowing for stimulation through hydro-fracking of large (>1 km3) geothermal reservoirs. Consequently we have adopted a different approach, obtaining heat production data rather then relying on the very sparse heat flow data. Birch and colleagues long since recognized the relationship between heat flow and heat production as an integral part of their concept of Heat Flow Provinces. Heat production is readily determined in the laboratory by measuring the density of a sample and the concentrations of its heat-producing elements potassium, uranium and thorium. We have determined the heat production for 570 samples from most of the major granitic and gneissic bodies in Massachusetts and Connecticut. We have also measured these parameters for 70 sedimentary rocks that cover granites and gneiss in the Connecticut and Narragansett Basins. This data is being used to calculate inferred heat flow data for these localities. Comparison of these inferred heat flow values with the sparse number of those measured directly in boreholes in the two States is encouraging, indicating that this approach has merit. We have also measured thermal conductivity on all of these samples. This, together with the measured heat production and the inferred heat flow allow the calculation of inferred temperature - depth profiles for these localities, from which we have produced maps showing the distribution of heat production, thermal conductivity, inferred heat flow and inferred temperatures at depths of 2, 4 and 6 km in the two States. We believe that this is a rapid and relatively cheap approach for evaluating the geothermal potential of a region lacking in heat flow data allowing identification of areas that warrant more detailed investigation which would include geophysical surveys and drilling. In Massachusetts and Connecticut such areas include the Fitchburg pluton, Permian granites and the Narragansett and Hartford Basins, where gneiss and granites are buried beneath Carboniferous and Triassic sediments respectively. This project is funded by the Department of Energy through an award to the Association of American State Geologists.

Rhodes, J. M.; Koteas, C.; Mabee, S. B.; Thomas, M.; Gagnon, T.

2012-12-01

10

Solar steam generation by heat localization  

E-print Network

Currently, steam generation using solar energy is based on heating bulk liquid to high temperatures. This approach requires either costly high optical concentrations leading to heat loss by the hot bulk liquid and heated ...

Ghasemi, Hadi

11

Interface Shape Control Using Localized Heating during Bridgman Growth  

NASA Technical Reports Server (NTRS)

Numerical calculations were performed to assess the effect of localized radial heating on the melt-crystal interface shape during vertical Bridgman growth. System parameters examined include the ampoule, melt and crystal thermal conductivities, the magnitude and width of localized heating, and the latent heat of crystallization. Concave interface shapes, typical of semiconductor systems, could be flattened or made convex with localized heating. Although localized heating caused shallower thermal gradients ahead of the interface, the magnitude of the localized heating required for convexity was less than that which resulted in a thermal inversion ahead of the interface. A convex interface shape was most readily achieved with ampoules of lower thermal conductivity. Increasing melt convection tended to flatten the interface, but the amount of radial heating required to achieve a convex interface was essentially independent of the convection intensity.

Volz, M. P.; Mazuruk, K.; Aggarwal, M. D.; Croll, A.

2008-01-01

12

Boiling local heat transfer enhancement in minichannels using nanofluids.  

PubMed

This paper reports an experimental study on nanofluid convective boiling heat transfer in parallel rectangular minichannels of 800 ?m hydraulic diameter. Experiments are conducted with pure water and silver nanoparticles suspended in water base fluid. Two small volume fractions of silver nanoparticles suspended in water are tested: 0.000237% and 0.000475%. The experimental results show that the local heat transfer coefficient, local heat flux, and local wall temperature are affected by silver nanoparticle concentration in water base fluid. In addition, different correlations established for boiling flow heat transfer in minichannels or macrochannels are evaluated. It is found that the correlation of Kandlikar and Balasubramanian is the closest to the water boiling heat transfer results. The boiling local heat transfer enhancement by adding silver nanoparticles in base fluid is not uniform along the channel flow. Better performances and highest effect of nanoparticle concentration on the heat transfer are obtained at the minichannels entrance. PMID:23506445

Chehade, Ali Ahmad; Gualous, Hasna Louahlia; Le Masson, Stephane; Fardoun, Farouk; Besq, Anthony

2013-01-01

13

Boiling local heat transfer enhancement in minichannels using nanofluids  

PubMed Central

This paper reports an experimental study on nanofluid convective boiling heat transfer in parallel rectangular minichannels of 800 ?m hydraulic diameter. Experiments are conducted with pure water and silver nanoparticles suspended in water base fluid. Two small volume fractions of silver nanoparticles suspended in water are tested: 0.000237% and 0.000475%. The experimental results show that the local heat transfer coefficient, local heat flux, and local wall temperature are affected by silver nanoparticle concentration in water base fluid. In addition, different correlations established for boiling flow heat transfer in minichannels or macrochannels are evaluated. It is found that the correlation of Kandlikar and Balasubramanian is the closest to the water boiling heat transfer results. The boiling local heat transfer enhancement by adding silver nanoparticles in base fluid is not uniform along the channel flow. Better performances and highest effect of nanoparticle concentration on the heat transfer are obtained at the minichannels entrance. PMID:23506445

2013-01-01

14

Characteristic of Local Boiling Heat Transfer of Ammonia / Water Binary Mixture on the Plate Type Evaporator  

NASA Astrophysics Data System (ADS)

Ocean thermal energy conversion (OTEC) and discharged thermal energy conversion (DTEC) are expected to be the next generation energy production systems. Both systems use a plate type evaporator, and ammonia or ammonia/water mixture as a working fluid. It is important to clarify heat transfer characteristic for designing efficient power generation systems. Measurements of local boiling heat transfer coefficients and visualization were performed for ammonia /water mixture (z = 0.9) on a vertical flat plate heat exchanger in a range of mass flux (7.5 - 15 kg/m2s), heat flux (15 - 23 kW/m2), and pressure (0.7 - 0.9 MPa). The result shows that in the case of ammonia /water mixture, the local heat transfer coefficients increase with an increase of vapor quality and mass flux, and decrease with an increase of heat flux, and the influence of the flow pattern on the local heat transfer coefficient is observed.

Okamoto, Akio; Arima, Hirofumi; Kim, Jeong-Hun; Akiyama, Hirokuni; Ikegami, Yasuyuki; Monde, Masanori

15

Cascade heat recovery with coproduct gas production  

DOEpatents

A process for the integration of a chemical absorption separation of oxygen and nitrogen from air with a combustion process is set forth wherein excess temperature availability from the combustion process is more effectively utilized to desorb oxygen product from the absorbent and then the sensible heat and absorption reaction heat is further utilized to produce a high temperature process stream. The oxygen may be utilized to enrich the combustion process wherein the high temperature heat for desorption is conducted in a heat exchange preferably performed with a pressure differential of less than 10 atmospheres which provides considerable flexibility in the heat exchange.

Brown, William R. (Zionsville, PA); Cassano, Anthony A. (Allentown, PA); Dunbobbin, Brian R. (Allentown, PA); Rao, Pradip (Allentown, PA); Erickson, Donald C. (Annapolis, MD)

1986-01-01

16

Cascade heat recovery with coproduct gas production  

DOEpatents

A process for the integration of a chemical absorption separation of oxygen and nitrogen from air with a combustion process is set forth wherein excess temperature availability from the combustion process is more effectively utilized to desorb oxygen product from the absorbent and then the sensible heat and absorption reaction heat is further utilized to produce a high temperature process stream. The oxygen may be utilized to enrich the combustion process wherein the high temperature heat for desorption is conducted in a heat exchange preferably performed with a pressure differential of less than 10 atmospheres which provides considerable flexibility in the heat exchange. 4 figs.

Brown, W.R.; Cassano, A.A.; Dunbobbin, B.R.; Rao, P.; Erickson, D.C.

1986-10-14

17

Measurement of flow field and local heat transfer distribution on a scraped heat exchanger crystalliser surface  

E-print Network

Measurement of flow field and local heat transfer distribution on a scraped heat exchanger.ravelet@laposte.net Geert-Jan Witkamp G.J.Witkamp@xs4all.nl Abstract In a cylindrical scraped heat exchanger crystallizer exchanger surface has been studied by direct measurements of the heat exchanger surface temperature

Boyer, Edmond

18

Generalized dynamic modeling of local heat transfer in bubble columns  

Microsoft Academic Search

Instantaneous local heat transfer rates were measured by using a hot-wire probe in three bubble columns of different diameters of 200, 400 and 800mm. The time series of heat transfer rates were analyzed by means of rescaled range (R\\/S) and deterministic chaos analyses. Due to the influence of highly chaotic bubble motions, the instantaneous local heat transfer exhibits low-dimensional chaotic

Wei Chen; Tatsuya Hasegawa; Atsushi Tsutsumi; Kentaro Otawara; Yoshiki Shigaki

2003-01-01

19

SOME CHARACTERISTICS OF HEAT PRODUCTION USING THE \\  

Microsoft Academic Search

Additional evidence is presented to show that heat production resulting from the Pons-Fleis- chmann Effect has a positive temperature coefficient, has a critical onset current density, and originates at the palladium cathode.

Edmund Storms

20

Local heat transfer measurements of plate finned-tube heat exchangers by infrared thermography  

Microsoft Academic Search

An experimental study is performed using an infrared thermovision to monitor temperature distribution over a plate-fin surface inside the plate finned-tube heat exchangers. The differentiation of the temperature function is derived to determine the local convective heat transfer coefficients on the tested fin, using a local element lumped conduction equation included the convective effect on the boundaries with experimental data.

Herchang Ay; JiinYuh Jang; Jer-Nan Yeh

2002-01-01

21

Solar steam generation by heat localization  

NASA Astrophysics Data System (ADS)

Currently, steam generation using solar energy is based on heating bulk liquid to high temperatures. This approach requires either costly high optical concentrations leading to heat loss by the hot bulk liquid and heated surfaces or vacuum. New solar receiver concepts such as porous volumetric receivers or nanofluids have been proposed to decrease these losses. Here we report development of an approach and corresponding material structure for solar steam generation while maintaining low optical concentration and keeping the bulk liquid at low temperature with no vacuum. We achieve solar thermal efficiency up to 85% at only 10?kW?m-2. This high performance results from four structure characteristics: absorbing in the solar spectrum, thermally insulating, hydrophilic and interconnected pores. The structure concentrates thermal energy and fluid flow where needed for phase change and minimizes dissipated energy. This new structure provides a novel approach to harvesting solar energy for a broad range of phase-change applications.

Ghasemi, Hadi; Ni, George; Marconnet, Amy Marie; Loomis, James; Yerci, Selcuk; Miljkovic, Nenad; Chen, Gang

2014-07-01

22

Solar steam generation by heat localization.  

PubMed

Currently, steam generation using solar energy is based on heating bulk liquid to high temperatures. This approach requires either costly high optical concentrations leading to heat loss by the hot bulk liquid and heated surfaces or vacuum. New solar receiver concepts such as porous volumetric receivers or nanofluids have been proposed to decrease these losses. Here we report development of an approach and corresponding material structure for solar steam generation while maintaining low optical concentration and keeping the bulk liquid at low temperature with no vacuum. We achieve solar thermal efficiency up to 85% at only 10 kW m(-2). This high performance results from four structure characteristics: absorbing in the solar spectrum, thermally insulating, hydrophilic and interconnected pores. The structure concentrates thermal energy and fluid flow where needed for phase change and minimizes dissipated energy. This new structure provides a novel approach to harvesting solar energy for a broad range of phase-change applications. PMID:25043613

Ghasemi, Hadi; Ni, George; Marconnet, Amy Marie; Loomis, James; Yerci, Selcuk; Miljkovic, Nenad; Chen, Gang

2014-01-01

23

Critical heat flux in a locally heated liquid film driven by gas flow in a minichannel  

NASA Astrophysics Data System (ADS)

The rupture of a liquid film driven by friction with a gas flow in a horizontal minichannel and the heat-exchange crisis in this film locally heated by a 1 × 1 cm source in the channel wall has been experimentally studied. A heat flux of 250 W/cm2 is achieved, which is greater by an order of magnitude than the limiting heat flux for a vertically falling liquid film with the same Reynolds number (Re l = 21). These experiments confirmed good prospects for using gas-flow-driven liquid films in cooling systems of devices with intense local heat evolution.

Zaitsev, D. V.; Rodionov, D. A.; Kabov, O. A.

2009-07-01

24

Local heat transfer in a rotating serpentine flow passage  

NASA Astrophysics Data System (ADS)

An experimental study is performed on the internal cooling of a rotating serpentine flow passage of square cross section with throughflow. The test section is not preceded by a hydrodynamic calming region, i.e., a leading arm, and is rotated at low Rossby numbers. The local heat transfer coefficients along the flow passage, including the leading wall, trailing wall, and sidewalls, are determined together with the circumferentially averaged values. The Reynolds, Rossby, and rotating Rayleigh numbers are varied to determine their effects on heat transfer performance. It is shown that heat transfer augmentation is significant at all sharp turns due to the presence of strong secondary flow. The rotational effect is very obvious and complicated in the local heat transfer performance but it is very minor for the average heat transfer performance. The throughflow rate plays an important role in the heat transfer performance.

Yang, Wen-Jei; Zhang, Nengli; Chiou, Jeff

1992-05-01

25

Wafer level bonding using localized radio-frequency induction heating  

Microsoft Academic Search

A wafer level bonding technique by localized induction heating has been developed and demonstrated in this paper. A suitable\\u000a fabrication process scheme has also been established for the localized induction heating and bonding. It takes only about\\u000a 20 seconds to complete the bonding process. The temperatures of solder loops and the central area of solder loops are above\\u000a 300°C and

MingXiang Chen; WenMing Liu; YanYan Xi; ChangYong Lin; Sheng Liu

2010-01-01

26

Maximum Skin Hyperaemia Induced by Local Heating: Possible Mechanisms  

Microsoft Academic Search

Background: Maximum skin hyperaemia (MH) induced by heating skin to ?42°C is impaired in individuals at risk of diabetes and cardiovascular disease. Interpretation of these findings is hampered by the lack of clarity of the mechanisms involved in the attainment of MH. Methods: MH was achieved by local heating of skin to 42–43°C for 30 min, and assessed by laser

Kim M. Gooding; Michael M. Hannemann; John E. Tooke; Geraldine F. Clough; Angela C. Shore

2006-01-01

27

Simultaneous microwave local heating and microwave thermography. Possible clinical applications.  

PubMed

A basic experiment showing the possibility of combining microwave local heating of subcutaneous living tissue, and microwave radiometry by the same system was carried out. The combined process may be used - in hyperthermia therapy, for measurement and control of the local temperature, - in some diagnoses using radiometry to detect diseased tissue. PMID:259082

N'Guyen, D D; Mamouni, A; Leroy, Y; Constant, E

1979-06-01

28

Heat production of nursery and growing piglets  

Technology Transfer Automated Retrieval System (TEKTRAN)

Heat and moisture production (HMP) values are used to size ventilation fans in animal housing. The HMP values that are currently published in the ASABE standards were from data published in 1975. This study is one of a series of studies being conducted to update the HMP values for the ASABE and ASHR...

29

Effects of gas bubble production on heat transfer from a volumetrically heated liquid pool  

NASA Astrophysics Data System (ADS)

Aqueous solutions of uranium salts may provide a new supply chain to fill potential shortfalls in the availability of the most common radiopharmaceuticals currently in use worldwide, including Tc99m which is a decay product of Mo99. The fissioning of the uranium in these solutions creates Mo99 but also generates large amounts of hydrogen and oxygen from the radiolysis of the water. When the dissolved gases reach a critical concentration, bubbles will form in the solution. Bubbles in the solution affect both the fission power and the heat transfer out of the solution. As a result, for safety and production calculations, the effects of the bubbles on heat transfer must be understood. A high aspect ratio tank was constructed to simulate a section of an annulus with heat exchangers on the inner and outer steel walls to provide cooling. Temperature measurements via thermocouples inside the tank and along the outside of the steel walls allowed the calculation of overall and local heat transfer coefficients. Different air injection manifolds allowed the exploration of various bubble characteristics and patterns on heat transfer from the pool. The manifold type did not appear to have significant impact on the bubble size distributions in water. However, air injected into solutions of magnesium sulfate resulted in smaller bubble sizes and larger void fractions than those in water at the same injection rates. One dimensional calculations provide heat transfer coefficient values as functions of the superficial gas velocity in the pool.

Bull, Geoffrey R.

30

Local heat transfer and flow distribution in a three-pass industrial heat exchanger  

Microsoft Academic Search

Local heat transfer from single tubes in an industrial-sized, three-pass heat exchanger of the inline tube bundle type was measured. The transversal and longitudinal pitches were 1.8D and 1.5D, respectively, the height of each pass was 30D and the Reynolds number was 20000. The measurements were made using an electrically heated cylindrical probe of the metallic film type, an instrument

D. N. Sørensen; S. L. Hvid; M. B. Hansen; K. E. Meyer

2001-01-01

31

A new solder bumping technology with local induction heating  

Microsoft Academic Search

A solder bumping method with the local induction heating called ISHR(induction self heat reflow) is put forwarded in this paper, and reflow experiment to form solder bump for the SnPb, SnAg and SnAgCu eutectic solder ball on the Au\\/Ni\\/Cu pad is performed using the ISHR. Solder bump formation mechanism during the ISHR process is investigated. The results shows that it

An Rong; Mingyu Li; Chunqing Wang

2005-01-01

32

Single thermal plume in locally heated vertical soap films.  

PubMed

A vertical soap film is maintained by injection of a soap solution from the top. The film is then locally heated. Thermal plumes may be observed to rise in the film, depending on the magnitude of the heating and injected flows. The nearly two-dimensional nature of the system allows to visualize the motion of the plumes using an infrared camera. A model is proposed to describe the growth, emergence, and stationarity of the plumes in the film by taking into account both magnitudes of the heating ?T and injected flow Q. PMID:22181270

Adami, N; Dorbolo, S; Caps, H

2011-10-01

33

Local heat transfer in a rotating serpentine flow passage  

SciTech Connect

An experimental study is performed on the internal cooling of a rotating serpentine flow passage of square cross section with throughflow. The test section is not proceeded by a hydrodynamic calming region, i.e., a leading arm, and is rotated at low Rossby numbers. The local heat transfer coefficients along the flow passage, including the leading wall, trailing wall, and sidewalls, are determined together with the circumferentially averaged values. The Reynolds, Rossby, and rotating Rayleigh numbers are varied to determine their effects on heat transfer performance. It is disclosed that heat transfer augmentation is significant at all sharp turns due to the presence of strong secondary flow. The rotational effect is very obvious and complicated in the local heat transfer performance but it is very minor on the average heat transfer performance. The throughflow rate plays an important role on the heat transfer performance. The results may serve as a baseline for comparison with the results from a model with a leading arm to determine the effects of a hydro-dynamic calming section on the heat transfer performance of a rotating serpentine flow passage.

Wenjei Yang; Nengli Zhang; Chiou, J. (Univ. of Michigan, Ann Arbor (United States))

1992-05-01

34

Determinants of heat production in newborn lambs  

NASA Astrophysics Data System (ADS)

Measurement of summit metabolism (the maximum rate of heat production) in lambs aged 1 or 4h revealed considerable between animal variation. Summit metabolism per unit body weight decreased as body weight increased whereas summit metabolism per unit body surface area was independent of body weight. Severe pre-partum hypoxia was apparently associated with a low summit metabolism at 1 or 4h of age which made such lambs very susceptible to hypothermia. This deficiency in heat production capacity did not appear to be a permanent featuresince most lambs so affected recovered full thermoregulatory ability by 12h of age. Feeding of colostrum conferred an immediate 18% increase in summit metabolism. The significance of these findings to the prevention of hypothermia in the newborn lamb is discussed.

Eales, F. A.; Small, J.

1980-06-01

35

Locally-smeared operator product expansions  

SciTech Connect

We propose a "locally-smeared Operator Product Expansion" (sOPE) to decompose non-local operators in terms of a basis of locally-smeared operators. The sOPE formally connects nonperturbative matrix elements of smeared degrees of freedom, determined numerically using the gradient flow, to non-local operators in the continuum. The nonperturbative matrix elements do not suffer from power-divergent mixing on the lattice, provided the smearing scale is kept fixed in the continuum limit. The presence of this smearing scale prevents a simple connection to the standard operator product expansion and therefore requires the construction of a two-scale formalism. We demonstrate the feasibility of our approach using the example of real scalar field theory.

Monahan, Christopher; Orginos, Kostantinos

2014-12-01

36

Local melt process of solder bumping by induction heating reflow  

Microsoft Academic Search

Purpose – The purpose of this paper is to describe a local melt process of solder bumping employed in electronic packaging applications by an induction heating reflow method, for a combined numerical and experimental study involving a temperature measurement using an infrared thermometer during the reflow process and microstructural observations after reflow, which can be used to control the height

Hongbo Xu; Mingyu Li; Yonggao Fu; Ling Wang; Jongmyung Kim

2009-01-01

37

Local heat transfer in a rotating serpentine flow passage  

Microsoft Academic Search

An experimental study is performed on the internal cooling of a rotating serpentine flow passage of square cross section with throughflow. The test section is not preceded by a hydrodynamic calming region, i.e., a leading arm, and is rotated at low Rossby numbers. The local heat transfer coefficients along the flow passage, including the leading wall, trailing wall, and sidewalls,

Wen-Jei Yang; Nengli Zhang; Jeff Chiou

1992-01-01

38

Enhancement of heat production through selective scaling  

SciTech Connect

The heat-depleted brine has to be reinjected whether it is for technical, economical, environmental and/or legal purposes. However, there are many problems related to injectivity and injectability in a geothermal field. The major drawback is the dread of an early breakthrough of the heat depleted brine at the production wells. It is believed that this drawback may be overcome through selective scaling. The results of investigation into the feasibility of selective scaling are summarized. Selective scaling is defined here as the process of intentionally precipitating large quantities of chemical compounds at selected locations, such as high permeability streaks or fractures, for the purpose of retarding the flow of injection fluids through these flow channels. Such flow retardation will increase the residence time of the injected fluids in the reservoir by a more suitable heat sweep thereby enhancing the heat extraction from the geothermal reservoir. Three different methods of selective scaling are discussed. These methods are: the injection of a thermodynamically unstable brine; injection of a slug of dirty brine or other thermodynamically unstable brine into selective locations of the reservoir; and mixing of an injection brine which is incompatible with a reservoir brine. The basis of these methods and their impact on the permeability characteristics of the reservoir are discussed through a precipitation model and through simple flow models. The application of these models are illustrated using Salton Sea brine and Currier 2 brine.

Vetter, O.J.; Kandarpa, V.; Harouaka, A.

1982-08-16

39

Non-Heat Treatable Alloy Sheet Products  

SciTech Connect

ALCAR is an innovative approach for conducting multi-company, pre-competitive research and development programs. ALCAR has been formed to crate a partnership of aluminum producers, the American Society of Mechanical Engineers Center for Research and Technology Development (ASME/CRTD), the United States Department of Energy (USDOE), three USDOE National Laboratories, and a Technical Advisory Committee for conducting cooperative, pre-competitive research on the development of flower-cost, non-heat treated (NHT) aluminum alloys for automotive sheet applications with strength, formability and surface appearance similar to current heat treated (HT) aluminum alloys under consideration. The effort has been supported by the USDOE, Office of Transportation Technology (OTT) through a three-year program with 50/50 cost share at a total program cost of $3 million. The program has led to the development of new and modified 5000 series aluminum ally compositions. Pilot production-size ingots have bee n melted, cast, hot rolled and cold rolled. Stamping trials on samples of rolled product for demonstrating production of typical automotive components have been successful.

Hayden, H.W.; Barthold, G.W.; Das, S.K.

1999-08-01

40

Specific heat of a non-local attractive Hubbard model  

NASA Astrophysics Data System (ADS)

The specific heat C(T) of an attractive (interaction G<0) non-local Hubbard model is investigated within a two-pole approximation that leads to a set of correlation functions, which play an important role as a source of anomalies as the pseudogap. For a giving range of G and nT (where nT=n?+n?), the specific heat as a function of the temperature presents a two peak structure. Nevertehelesss, the presence of a pseudogap eliminates the two peak structure. The effects of the second nearest-neighbor hopping on C(T) are also investigated.

Calegari, E. J.; Lobo, C. O.; Magalhaes, S. G.; Chaves, C. M.; Troper, A.

2013-10-01

41

Characterization of local heat fluxes around ICRF antennas on JET  

NASA Astrophysics Data System (ADS)

When using Ion Cyclotron Range of Frequency (ICRF) heating, enhanced power deposition on Plasma-Facing Components (PFCs) close to the antennas can occur. Experiments have recently been carried out on JET with the new ITER-Like-Wall (ILW) to characterize the heat fluxes on the protection of the JET ICRF antennas, using Infra-Red (IR) thermography measurement. The measured heat flux patterns along the poloidal limiters surrounding powered antennas were compared to predictions from a simple RF sheath rectification model. The RF electric field, parallel to the static magnetic field in front of the antenna, was evaluated using the TOPICA code, integrating a 3D flattened model of the JET A2 antennas. The poloidal density variation in front of the limiters was obtained from the mapping of the Li-beam or edge reflectometry measurements using the flux surface geometry provided by EFIT equilibrium reconstruction. In many cases, this simple model can well explain the position of the maximum heat flux on the different protection limiters and the heat-flux magnitude, confirming that the parallel RF electric field and the electron plasma density in front of the antenna are the main driving parameters for ICRF-induced local heat fluxes.

Campergue, A.-L.; Jacquet, P.; Bobkov, V.; Milanesio, D.; Monakhov, I.; Colas, L.; Arnoux, G.; Brix, M.; Sirinelli, A.; JET-EFDA Contributors

2014-02-01

42

Local and Nonlocal Parallel Heat Transport in General Magnetic Fields  

SciTech Connect

A novel approach for the study of parallel transport in magnetized plasmas is presented. The method avoids numerical pollution issues of grid-based formulations and applies to integrable and chaotic magnetic fields with local or nonlocal parallel closures. In weakly chaotic fields, the method gives the fractal structure of the devil's staircase radial temperature profile. In fully chaotic fields, the temperature exhibits self-similar spatiotemporal evolution with a stretched-exponential scaling function for local closures and an algebraically decaying one for nonlocal closures. It is shown that, for both closures, the effective radial heat transport is incompatible with the quasilinear diffusion model.

Castillo-Negrete, D. del; Chacon, L. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-8071 (United States)

2011-05-13

43

Experimental and theoretical analysis of the local condensation heat transfer in a plate heat exchanger  

NASA Astrophysics Data System (ADS)

Plate heat exchanger (PHE) are today widely used in industrial heat transfer applications due to their good thermal performance, modest space requirement, easy accessibility to all areas and their lower capital and operating costs as compared to shell-and-tube heat exchangers. Although authoritative models for the design of PHE used as condensers are missing, the number of applications where a PHE is operating as a condenser increases. On the way to a reliable model based on physical approaches for the prediction of heat transfer and pressure drop during the condensation process inside a PHE, the flow and heat interactions as well as their dependence on the geometrical parameters of the corrugated plates and the operating conditions must be studied in detail. In this work the stepwise procedure for the fundamental construction of such a model is described. An experimental setup was built to analyze the characteristics of the two-phase-flow in PHE. A single gap, consisting of two transparent corrugated plates, was tested with a two-phase flow of air/water and also with boiling refrigerant R365mfc. Flow pattern maps were constructed for plates with corrugation angles of 27 and 63 degrees relative to the direction of flow. Investigations of the local heat transfer coefficients and the pressure drop were done with the same plates. The measurement of the local heat transfer coefficients was carried out by the use of the "Temperature Oscillation InfraRed Thermography" (TOIRT) method. Based on these results three main flow patterns are defined: film flow, bubbly flow and slug flow. For each of the three flow patterns an own model for the heat transfer and pressure drop mechanism are developed and the heat transfer coefficient and the friction factor is calculated with different equations depending on the actual steam quality, mass flow and geometrical parameters by means of a flow pattern map. The theory of the flow pattern based prediction models is proved with own experimental data. The measurements were carried out with an experimental setup in a technical scale. The refrigerant cycle works with R134a as refrigerant and involves two PHEs, used as condenser and evaporator, and a 55 kWel compressor for the compression of the vapor phase. The setup allows the measurement of quasi-local heat transfer coefficients inside the PHEs. Additional heat exchangers assure saturated vapor at the inlet and saturated liquid at the outlet of the condenser.

Grabenstein, V.; Kabelac, S.

2012-11-01

44

The erosion of a salinity step by a localized heat source  

E-print Network

The erosion of a salinity step by a localized heat source D.M. Leppinen and S.B. Dalziel Department compare the erosion a salinity step by a localized heat source with the erosion of the same salinity step layers and it is shown that a localized heat source is more e cient at eroding a salinity step than

Dalziel, Stuart

45

Chemothermal therapy for localized heating and ablation of tumor.  

PubMed

Chemothermal therapy is a new hyperthermia treatment on tumor using heat released from exothermic chemical reaction between the injected reactants and the diseased tissues. With the highly minimally invasive feature and localized heating performance, this method is expected to overcome the ubiquitous shortcomings encountered by many existing hyperthermia approaches in ablating irregular tumor. This review provides a relatively comprehensive review on the latest advancements and state of the art in chemothermal therapy. The basic principles and features of two typical chemothermal ablation strategies (acid-base neutralization-reaction-enabled thermal ablation and alkali-metal-enabled thermal/chemical ablation) are illustrated. The prospects and possible challenges facing chemothermal ablation are analyzed. The chemothermal therapy is expected to open many clinical possibilities for precise tumor treatment in a minimally invasive way. PMID:23965596

Deng, Zhong-Shan; Liu, Jing

2013-01-01

46

Localized heating and bonding technique for MEMS packaging  

NASA Astrophysics Data System (ADS)

Localized heating and bonding techniques have been developed for hermetic and vacuum packaging of MEMS devices, including silicon-to-glass fusion, silicon-gold eutectic, and silicon-to-glass bonding using PSG, indium, aluminum, and aluminum/silicon alloy as the intermediate layer. Line shaped phosphorus-doped polysilicon or gold films are used as resistive microheaters to provide enough thermal energy for bonding. The bonding processes are conducted in the common environment of room temperature and atmospheric pressure and can achieve bonding strength comparable to the fracture toughness of bulk silicon in less than 10 minutes. About 5 watts of input power is needed for localized bonding which can seal a 500 x 500 mum2 area. The total input power is determined by the thermal properties of bonding materials, including the heat capacity and latent heat. Two important bonding results are obtained: (1) The surface step created by the electrical interconnect line can be planarized by reflowing the metal solder. (2) Small applied pressure, less than 1MPa, for intimate contact reduces mechanical damage to the device substrate. This new class of bonding technology has potential applications for MEMS fabrication and packaging that require low temperature processing at the wafer level, excellent bonding strength and hermetic sealing characteristics. A hermetic package based on localized aluminum/silicon-to-glass bonding has been successfully fabricated. Less than 0.2 MPa contact pressure with 46mA input current for two parallel 3.5mum wide polysilicon on-chip microheaters can create as high as 700°C bonding temperature and achieve a strong and reliable bond in 7.5 minutes. Accelerated testing in an autoclave shows some packages survive more than 450 hours under 3 atm, 100%RH and 128°C. Premature failure has been attributed to some unbonded regions on the failed samples. The bonding yield and reliability have been improved by increasing bonding time and applied pressure. Finally, vacuum encapsulation of folded-beam comb-drive mu-resonators used as pressure monitors has been demonstrated using localized aluminum/silicon-to-glass bonding. With 3.4 watt heating power, ˜0.2MPa applied contact pressure, and 90 minutes wait time before bonding, vacuum encapsulation can be achieved with the same vacuum level as the packaging environment which is about 25 mtorr. Metal coating used as diffusion barrier and a longer wait time before bonding are used to improve the vacuum level of the package. Long-term measurement of the Q of un-annealed vacuum-packaged mu-resonators, illustrates stable operation after 19 weeks.

Cheng, Yu-Ting

47

Technologies for Production of Heat and Electricity  

SciTech Connect

Biomass is a desirable source of energy because it is renewable, sustainable, widely available throughout the world, and amenable to conversion. Biomass is composed of cellulose, hemicellulose, and lignin components. Cellulose is generally the dominant fraction, representing about 40 to 50% of the material by weight, with hemicellulose representing 20 to 50% of the material, and lignin making up the remaining portion [4,5,6]. Although the outward appearance of the various forms of cellulosic biomass, such as wood, grass, municipal solid waste (MSW), or agricultural residues, is different, all of these materials have a similar cellulosic composition. Elementally, however, biomass varies considerably, thereby presenting technical challenges at virtually every phase of its conversion to useful energy forms and products. Despite the variances among cellulosic sources, there are a variety of technologies for converting biomass into energy. These technologies are generally divided into two groups: biochemical (biological-based) and thermochemical (heat-based) conversion processes. This chapter reviews the specific technologies that can be used to convert biomass to energy. Each technology review includes the description of the process, and the positive and negative aspects.

Jacob J. Jacobson; Kara G. Cafferty

2014-04-01

48

Strong contributions of local background climate to urban heat islands  

NASA Astrophysics Data System (ADS)

The urban heat island (UHI), a common phenomenon in which surface temperatures are higher in urban areas than in surrounding rural areas, represents one of the most significant human-induced changes to Earth's surface climate. Even though they are localized hotspots in the landscape, UHIs have a profound impact on the lives of urban residents, who comprise more than half of the world's population. A barrier to UHI mitigation is the lack of quantitative attribution of the various contributions to UHI intensity (expressed as the temperature difference between urban and rural areas, ?T). A common perception is that reduction in evaporative cooling in urban land is the dominant driver of ?T (ref. 5). Here we use a climate model to show that, for cities across North America, geographic variations in daytime ?T are largely explained by variations in the efficiency with which urban and rural areas convect heat to the lower atmosphere. If urban areas are aerodynamically smoother than surrounding rural areas, urban heat dissipation is relatively less efficient and urban warming occurs (and vice versa). This convection effect depends on the local background climate, increasing daytime ?T by 3.0 +/- 0.3 kelvin (mean and standard error) in humid climates but decreasing ?T by 1.5 +/- 0.2 kelvin in dry climates. In the humid eastern United States, there is evidence of higher ?T in drier years. These relationships imply that UHIs will exacerbate heatwave stress on human health in wet climates where high temperature effects are already compounded by high air humidity and in drier years when positive temperature anomalies may be reinforced by a precipitation-temperature feedback. Our results support albedo management as a viable means of reducing ?T on large scales.

Zhao, Lei; Lee, Xuhui; Smith, Ronald B.; Oleson, Keith

2014-07-01

49

Scanning from heating: 3D shape estimation of transparent objects from local surface heating.  

PubMed

Today, with quality becoming increasingly important, each product requires three-dimensional in-line quality control. On the other hand, the 3D reconstruction of transparent objects is a very difficult problem in computer vision due to transparency and specularity of the surface. This paper proposes a new method, called Scanning From Heating (SFH), to determine the surface shape of transparent objects using laser surface heating and thermal imaging. Furthermore, the application to transparent glass is discussed and results on different surface shapes are presented. PMID:19582061

Eren, Gonen; Aubreton, Olivier; Meriaudeau, Fabrice; Sanchez Secades, L A; Fofi, David; Naskali, A Teoman; Truchetet, Frederic; Ercil, Aytul

2009-07-01

50

Martian surface heat production and crustal heat flow from Mars Odyssey Gamma-Ray spectrometry  

NASA Astrophysics Data System (ADS)

Martian thermal state and evolution depend principally on the radiogenic heat-producing element (HPE) distributions in the planet's crust and mantle. The Gamma-Ray Spectrometer (GRS) on the 2001 Mars Odyssey spacecraft has mapped the surface abundances of HPEs across Mars. From these data, we produce the first models of global and regional surface heat production and crustal heat flow. As previous studies have suggested that the crust is a repository for approximately 50% of the radiogenic elements on Mars, these models provide important, directly measurable constraints on Martian heat generation. Our calculations show considerable geographic and temporal variations in crustal heat flow, and demonstrate the existence of anomalous heat flow provinces. We calculate a present day average surface heat production of 4.9 ± 0.3 × 10-11 W · kg-1. We also calculate the average crustal component of heat flow of 6.4 ± 0.4 mW · m-2. The crustal component of radiogenically produced heat flow ranges from <1 mW · m-2 in the Hellas Basin and Utopia Planitia regions to ˜13 mW · m-2 in the Sirenum Fossae region. These heat production and crustal heat flow values from geochemical measurements support previous heat flow estimates produced by different methodologies.

Hahn, B. C.; McLennan, S. M.; Klein, E. C.

2011-07-01

51

Wave transmission, phonon localization, and heat conduction of a one-dimensional Frenkel-Kontorova chain  

E-print Network

Wave transmission, phonon localization, and heat conduction of a one-dimensional Frenkel the fundamental properties, such as the wave transmission, heat conduction, and other low these related properties, namely, the wave transmission, the heat conduc- tion, and the phonon localization in 1

Li, Baowen

52

Homogeneous Thermal Cloak with Constant Conductivity and Tunable Heat Localization  

PubMed Central

Invisible cloak has long captivated the popular conjecture and attracted intensive research in various communities of wave dynamics, e.g., optics, electromagnetics, acoustics, etc. However, their inhomogeneous and extreme parameters imposed by transformation-optic method will usually require challenging realization with metamaterials, resulting in narrow bandwidth, loss, polarization-dependence, etc. In this paper, we demonstrate that thermodynamic cloak can be achieved with homogeneous and finite conductivity only employing naturally available materials. It is demonstrated that the thermal localization inside the coating layer can be tuned and controlled robustly by anisotropy, which enables an incomplete cloak to function perfectly. Practical realization of such homogeneous thermal cloak has been suggested by using two naturally occurring conductive materials, which provides an unprecedentedly plausible way to flexibly realize thermal cloak and manipulate heat flow with phonons. PMID:23549139

Han, Tiancheng; Yuan, Tao; Li, Baowen; Qiu, Cheng-Wei

2013-01-01

53

Local thermodynamic equilibrium in rapidly heated high energy density plasmas  

NASA Astrophysics Data System (ADS)

Emission spectra and the dynamics of high energy density plasmas created by optical and Free Electron Lasers (FELs) depend on the populations of atomic levels. Calculations of plasma emission and ionization may be simplified by assuming Local Thermodynamic Equilibrium (LTE), where populations are given by the Saha-Boltzmann equation. LTE can be achieved at high densities when collisional processes are much more significant than radiative processes, but may not be valid if plasma conditions change rapidly. A collisional-radiative model has been used to calculate the times taken by carbon and iron plasmas to reach LTE at varying densities and heating rates. The effect of different energy deposition methods, as well as Ionization Potential Depression are explored. This work shows regimes in rapidly changing plasmas, such as those created by optical lasers and FELs, where the use of LTE is justified, because timescales for plasma changes are significantly longer than the times needed to achieve an LTE ionization balance.

Aslanyan, V.; Tallents, G. J.

2014-06-01

54

Local thermodynamic equilibrium in rapidly heated high energy density plasmas  

SciTech Connect

Emission spectra and the dynamics of high energy density plasmas created by optical and Free Electron Lasers (FELs) depend on the populations of atomic levels. Calculations of plasma emission and ionization may be simplified by assuming Local Thermodynamic Equilibrium (LTE), where populations are given by the Saha-Boltzmann equation. LTE can be achieved at high densities when collisional processes are much more significant than radiative processes, but may not be valid if plasma conditions change rapidly. A collisional-radiative model has been used to calculate the times taken by carbon and iron plasmas to reach LTE at varying densities and heating rates. The effect of different energy deposition methods, as well as Ionization Potential Depression are explored. This work shows regimes in rapidly changing plasmas, such as those created by optical lasers and FELs, where the use of LTE is justified, because timescales for plasma changes are significantly longer than the times needed to achieve an LTE ionization balance.

Aslanyan, V.; Tallents, G. J. [York Plasma Institute, Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom)

2014-06-15

55

Solving Heat Conduction Problems by the Direct Meshless Local Petrov-Galerkin (DMLPG) method  

E-print Network

Solving Heat Conduction Problems by the Direct Meshless Local Petrov-Galerkin (DMLPG) method Davoud¨ottingen, Germany. SUMMARY As an improvement of the Meshless Local Petrov­Galerkin (MLPG), the Direct Meshless Local; Meshless methods; MLPG methods; DMLPG methods; Heat conduction problem. 1. INTRODUCTION Meshless methods

Schaback, Robert

56

Defining and Marketing “Local” Foods: Geographical Indications for US Products  

Microsoft Academic Search

What are local foods? If you do not know your local producer, then how can you know whether the product you are purchasing is local? These questions are at the heart of an emerging debate in the U.S. about authenticity and the value of local eating. From the menus of its elite restaurants, to urban farmer markets, to the procurement

Daniele Giovannucci; Elizabeth Barham; Richard Pirog

2010-01-01

57

Rural tourism and visitors' expenditures for local food products  

Microsoft Academic Search

Skuras D., Dimara E. and Petrou A (2006) Rural tourism and visitors' expenditures for local food products, Regional Studies40, 769–779. European rural development policy has supported the production of local and regionally denominated food as a means to differentiate agricultural production, and rural tourism as a means to diversify rural employment. The aim of the present work is to address

Dimitris Skuras; Efthalia Dimara; Anastasia Petrou

2006-01-01

58

Comparison of local and regional heat transport processes into the subsurface urban heat island of Karlsruhe, Germany  

NASA Astrophysics Data System (ADS)

Temperatures in shallow urban ground are typically elevated. They manifest as subsurface urban heat islands, which are observed worldwide in different metropolitan areas and which have a site-specific areal extent and intensity. As of right now the governing heat transport processes accumulating heat in the subsurface of cities are insufficiently understood. Based on a spatial assessment of groundwater temperatures, six individual heat flux processes could be identified: (1) heat flux from elevated ground surface temperatures (GST), (2) heat flux from basements of buildings, (3) reinjection of thermal waste water, (4) sewage drains, (5) sewage leakage, and (6) district heating. In this study, the contributions of these processes are quantified on local and regional scales for the city of Karlsruhe in Germany. For the regional scale, the Regionalized Monte Carlo (RMC) method is used. This method applies a single Monte Carlo (MC) simulation for the entire study area. At relatively low data demand, the RMC method provides basic insights into the heat contribution for the entire city. For the local scale, the Local Monte Carlo (LMC) method was developed and applied. This method analyzes all dominant heat fluxes spatially dependent by performing an MC simulation for each arbitrary sized pixel of the study area (here 10 x 10 m). This more intricate approach allows for a spatial representation of all heat flux processes, which is necessary for the local planning of geothermal energy use. In order to evaluate the heat transport processes on a regional scale, we compared the mean annual thermal energies that result from the individual heat flux processes. Both methods identify the heat flux from elevated GST and the heat flux from buildings as the dominant regional processes. However, reinjection of thermal wastewater is by far the most dominant local heat flux processes with an average heat flux of 16 ± 2 W/m2 in the affected areas. Although being dominant on the regional scale, fluxes from elevated GST and buildings only contribute with minor heat fluxes of 0.1 ± 0.3 W/m2 and 0.7 ± 0.8 W/m2, respectively, which clearly shows that such differences in heat fluxes should be carefully considered for the site specific and local planning of geothermal installations.

Benz, Susanne; Bayer, Peter; Menberg, Kathrin; Blum, Philipp

2014-05-01

59

Local Measurement of Fuel Energy Deposition and Heat Transfer Environment During Fuel Lifetime Using Controlled Calorimetry  

SciTech Connect

A comprehensive description of the accomplishments of the DOE grant titled, ''Local Measurement of Fuel Energy Deposition and Heat Transfer Environment During Fuel Lifetime using Controlled Calorimetry''.

Don W. Miller; Andrew Kauffmann; Eric Kreidler; Dongxu Li; Hanying Liu; Daniel Mills; Thomas D. Radcliff; Joseph Talnagi

2001-12-31

60

New industrial heat pump applications to phosphate fertilizer production  

SciTech Connect

In this study Process Integration techniques based on Pinch Technology have been applied to Chevron's fertilizer complex in Rock Springs, Wyoming. The objectives of the study were to: identify heat pump opportunities and to determine the cost effectiveness of heat pumping compared to other process improvements. Significance of this Work Chevron's fertilizer complex is an example of an exothermic process. The sulfuric acid plant produces more heat than is needed for the rest of the site. The complex has, therefore, no need for a heating utility. The heat created in the sulfuric acid plant is used to produce high pressure steam, which is let down through a turbo generator satisfying most of the site's electrical needs. This type of process would normally not be considered for heat pumping because there is no heating utility load to reduce. However, reducing the requirements for extraction steam will liberate more steam for power generation. Heat recovery and heat pumping, therefore, have the unusual effect of an increase in electricity production, resulting in a reduction in electricity import, rather than a reduction in fuel consumption. Heat recovery opportunities show promise at both the sulfuric acid and phosphoric acid plants. No economically attractive opportunities were found for heat pumps in the process units when they were considered individually; however, the study identified that significant energy savings can be achieved by heat integration between the sulfuric acid plant and the phosphoric acid plant. 16 figs.

Not Available

1990-06-01

61

Rubisco activase and wheat productivity under heat stress conditions  

Technology Transfer Automated Retrieval System (TEKTRAN)

Rubisco activase (RCA) constrains the photosynthetic potential of plants at high temperature (heat stress). We hypothesized that endogenous levels of RCA could serve as an important determinant of plant productivity under heat stress conditions. In this study, we investigated the possible relation...

62

NGNP Process Heat Applications: Hydrogen Production Accomplishments for FY2010  

SciTech Connect

This report summarizes FY10 accomplishments of the Next Generation Nuclear Plant (NGNP) Engineering Process Heat Applications group in support of hydrogen production technology development. This organization is responsible for systems needed to transfer high temperature heat from a high temperature gas-cooled reactor (HTGR) reactor (being developed by the INL NGNP Project) to electric power generation and to potential industrial applications including the production of hydrogen.

Charles V Park

2011-01-01

63

77 FR 33486 - Certain Integrated Circuit Packages Provided With Multiple Heat-Conducting Paths and Products...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Circuit Packages Provided With Multiple Heat- Conducting Paths and Products Containing...Circuit Packages Provided With Multiple Heat-Conducting Paths and Products Containing...circuit packages provided with multiple heat-conducting paths and products...

2012-06-06

64

77 FR 39735 - Certain Integrated Circuit Packages Provided With Multiple Heat-Conducting Paths and Products...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Circuit Packages Provided With Multiple Heat- Conducting Paths and Products Containing...circuit packages provided with multiple heat-conducting paths and products containing...circuit packages provided with multiple heat-conducting paths and products...

2012-07-05

65

Effect of Heating Treatments, Processing Methods and Refrigerated Storage of Milk and Some Dairy Products on Lipids Oxidation  

Microsoft Academic Search

The effect of heating treatments (pasteurization and boiling), micro waving, processing steps and storage of milk and some locally produced dairy products (Brined white cheese (Nabulsi), Yogurt and Labaneh on chemical changes of milk lipids were evaluated. The Peroxide value (POV) p-anisidine value (p-AV), thiobarbituric acid (TBA), free fatty acid and totox were determined. The heating treatments of milk do

2008-01-01

66

Heat-Pipe-Associated Localized Thermoelectric Power Generation System  

NASA Astrophysics Data System (ADS)

The present study focused on how to improve the maximum power output of a thermoelectric generator (TEG) system and move heat to any suitable space using a TEG associated with a loop thermosyphon (loop-type heat pipe). An experimental study was carried out to investigate the power output, the temperature difference of the thermoelectric module (TEM), and the heat transfer performance associated with the characteristic of the researched heat pipe. Currently, internal combustion engines lose more than 35% of their fuel energy as recyclable heat in the exhaust gas, but it is not easy to recycle waste heat using TEGs because of the limited space in vehicles. There are various advantages to use of TEGs over other power sources, such as the absence of moving parts, a long lifetime, and a compact system configuration. The present study presents a novel TEG concept to transfer heat from the heat source to the sink. This technology can transfer waste heat to any location. This simple and novel design for a TEG can be applied to future hybrid cars. The present TEG system with a heat pipe can transfer heat and generate power of around 1.8 V with T TEM = 58°C. The heat transfer performance of a loop-type heat pipe with various working fluids was investigated, with water at high heat flux (90 W) and 0.05% TiO2 nanofluid at low heat flux (30 W to 70 W) showing the best performance in terms of power generation. The heat pipe can transfer the heat to any location where the TEM is installed.

Kim, Pan-Jo; Rhi, Seok-Ho; Lee, Kye-Bock; Hwang, Hyun-Chang; Lee, Ji-Su; Jang, Ju-Chan; Lee, Wook-Hyun; Lee, Ki-Woo

2014-06-01

67

Localized induction heating solder bonding for wafer level MEMS packaging  

Microsoft Academic Search

This paper reports a new solder bonding method for the wafer level packaging of MEMS devices. The electroplated magnetic film was heated up using the induction heating, and leaded to solder reflow. It took only several seconds to complete the solder reflow and bonding process. The measurement results showed that the temperature of device region was only 110°C during heating.

Hsueh-An Yang; Mingching Wu; Weileun Fang

2004-01-01

68

Heat localization for targeted tumor treatment with nanoscale near-infrared radiation absorbers  

NASA Astrophysics Data System (ADS)

Focusing heat delivery while minimizing collateral damage to normal tissues is essential for successful nanoparticle-mediated laser-induced thermal cancer therapy. We present thermal maps obtained via magnetic resonance imaging characterizing laser heating of a phantom tissue containing a multiwalled carbon nanotube inclusion. The data demonstrate that heating continuously over tens of seconds leads to poor localization (? 0.5 cm) of the elevated temperature region. By contrast, for the same energy input, heat localization can be reduced to the millimeter rather than centimeter range by increasing the laser power and shortening the pulse duration. The experimental data can be well understood within a simple diffusive heat conduction model. Analysis of the model indicates that to achieve 1 mm or better resolution, heating pulses of ?2?s or less need to be used with appropriately higher heating power. Modeling these data using a diffusive heat conduction analysis predicts parameters for optimal targeted delivery of heat for ablative therapy.

Xie, Bin; Singh, Ravi; Torti, F. M.; Keblinski, Pawel; Torti, Suzy

2012-09-01

69

Heat localization for targeted tumor treatment with nanoscale near-infrared radiation absorbers  

PubMed Central

Focusing heat delivery while minimizing collateral damage to normal tissues is essential for successful nanoparticle-mediated laser-induced thermal cancer therapy. We present thermal maps obtained via magnetic resonance imaging (MRI) characterizing laser heating of a phantom tissue containing a multiwalled carbon nanotube inclusion. The data demonstrate that heating continuously over tens of seconds leads to poor localization (~ 0.5 cm) of the elevated temperature region. By contrast, for the same energy input, heat localization can be reduced to the millimeter rather than centimeter range by increasing the laser power and shortening the pulse duration. The experimental data can be well understood within a simple diffusive heat conduction model. Analysis of the model indicates that to achieve 1 mm or better resolution, heating pulses of ~ 2s or less need to be used with appropriately higher heating power. Modeling these data using a diffusive heat conduction analysis predicts parameters for optimal targeted delivery of heat for ablative therapy. PMID:22948207

Xie, Bin; Singh, Ravi; Torti, F. M.; Keblinski, Pawel; Torti, Suzy

2012-01-01

70

THE IMPACT OF HURRICANE STRIKES ON LOCAL CROPLAND PRODUCTIVITY  

E-print Network

THE IMPACT OF HURRICANE STRIKES ON LOCAL CROPLAND PRODUCTIVITY: EVIDENCE FROM THE CARIBBEAN Eric://www.enseignement.polytechnique.fr/economie/ mailto:chantal.poujouly@polytechnique.edu hal-00393883,version1-10Jun2009 #12;THE IMPACT OF HURRICANE° 2009-14 Abstract: We empirically estimate the impact of hurricane strikes on local crop productivity

Paris-Sud XI, Université de

71

Measured Local Heat Transport in Turbulent Rayleigh-Benard Convection X.-D. Shang,1  

E-print Network

Measured Local Heat Transport in Turbulent Rayleigh-Be´nard Convection X.-D. Shang,1 X.-L. Qiu,2 P September 2002; published 20 February 2003) Local convective heat flux in turbulent thermal convection is obtained from simultaneous velocity and temperature measurements in an aspect-ratio-one convection cell

Tong, Penger

72

PUBLISHED VERSION Characterization of local heat fluxes around ICRF antennas on JET  

E-print Network

PUBLISHED VERSION Characterization of local heat fluxes around ICRF antennas on JET A.-L. Campergue at : http://dx.doi.org/10.1063/1.4864538 #12;Characterization of local heat fluxes around ICRF antennas Antennas on JET AL. Camperguea , P. Jacquetb , V. Bobkovc , D. Milanesiod , I. Monakhovb , L. Colase , G

73

Correlation between suprathermal electron bursts, broadband extremely low frequency waves, and local ion heating in the  

E-print Network

Correlation between suprathermal electron bursts, broadband extremely low frequency waves+ and H+ ion heating and with localized extra low frequency (ELF) (1­10 Hz) magnetic field wave power suprathermal electron bursts, broadband extremely low frequency waves, and local ion heating in the midaltitude

Lotko, William

74

Reconstruction of local heat fluxes in pool boiling experiments along the entire boiling curve from high  

E-print Network

Reconstruction of local heat fluxes in pool boiling experiments along the entire boiling curve from conduction problem (IHCP) defined on an irregular three-dimensional (3D) domain in pool boiling experiments heating foil pressed to the bottom of the heater. The heat flux at the inaccessible boiling side

75

District heating from electric-generating plants and municipal incinerators: local planner's assessment guide  

SciTech Connect

This guide is designed to aid local government planners in the preliminary evaluation of the feasibility of district heating using heat recovered from electric generating plants and municipal incinerators. System feasibility is indicated by: (1) the existence of an adequate supply of nearby waste heat, (2) the presence of a sufficiently dense and large thermal load, and (3) a favorable cost comparison with conventional heating methods. 34 references.

Pferdehirt, W.; Kron, N. Jr.

1980-11-01

76

Interfacing primary heat sources and cycles for thermochemical hydrogen production  

SciTech Connect

Advantages cited for hydrogen production from water by coupling thermochemical cycles with primary heat include the possibility of high efficiencies. These can be realized only if the cycle approximates the criteria required to match the characteristics of the heat source. Different types of cycles may be necessary for fission reactors, for fusion reactors or for solar furnaces. Very high temperature processes based on decomposition of gaseous H/sub 2/O or CO/sub 2/ appear impractical even for projected solar technology. Cycles based on CdO decomposition are potentially quite efficient and require isothermal heat at temperatures that may be available from solar furnaces of fusion reactors. Sulfuric acid and solid sulfate cycles are potentially useful at temperatures available from each heat source. Solid sulfate cycles offer advantages for isothermal heat sources. All cycles under development include concentration and drying steps. Novel methods for improving such operations would be beneficial.

Bowman, M.G.

1980-01-01

77

Localized induction heating solder bonding for wafer level MEMS packaging  

Microsoft Academic Search

This paper reports a new solder bonding method for the wafer level packaging of MEMS devices. Electroplated magnetic film was heated using induction heating causing the solder to reflow. The experiment results show that it took less than 1 min to complete the bonding process. In addition, the MEMS devices experienced a temperature of only 110 °C during bonding, thus

Hsueh-An Yang; Mingching Wu; Weileun Fang

2005-01-01

78

Heat production during contraction in skeletal muscle of hypothyroid mice  

SciTech Connect

The effect of hypothyroidism on tension-independent and -dependent heat produced during a twitch and a tetanic contraction of extensor digitorum longus (EDL) and soleus muscle of mice was examined. The amount of heat produced during a twitch and the rate of heat development during a tetanus of EDL and soleus were measured at and above optimal length. The effect of hypothyroidism on force production was <30%. Straight lines were used to fit the relation between heat production and force. Hypothyroidism significantly decreases tension-independent heat during contraction of EDL and soleus muscle. Because the tension-independent heat is considered to be related to the Ca{sup 2+} cycling, these findings suggest that ATP splitting due to the Ca{sup 2+} cycling is reduced in hypothyroid mice. This conclusion was strengthened by the observation that the oxalate-supported {sup 45}Ca{sup 2+}-uptake activity and {sup 45}Ca{sup 2+}-loading capacity of muscle homogenates from hypothyroid mice were reduced, respectively, to 51 and to 65% in soleus and to 63 and 73% in EDL muscle as compared with euthyroid mice. The tension-dependent rate of heat development during a tetanus was also decreased in soleus muscle of hypothyroid mice. This suggests a lower rate of ATP hydrolysis related to cross-bridge cycling in this muscle due to the hypothyroid state.

Leijendekker, W.J.; van Hardeveld, C.; Elzinga, G. (Free Univ., Amsterdam (Netherlands))

1987-08-01

79

Effect of whole-body and local heating on cutaneous vasoconstrictor responses in humans  

NASA Technical Reports Server (NTRS)

Animal studies suggest that alpha-adrenergic-mediated vasoconstriction is compromised during whole-body heating. The purpose of this study was to identify whether whole-body heating and/or local surface heating reduce cutaneous alpha-adrenergic vasoconstrictor responsiveness in human skin. Protocol I: Six subjects were exposed to neutral skin temperature (i.e., 34 degrees C), whole-body heating, and local heating of forearm skin to increase skin blood flow to the same relative magnitude as that observed during whole-body heating. Protocol II: In eight subjects forearm skin was locally heated to 34, 37, 40, and 42 degrees C. During both protocols, alpha-adrenergic vasoconstrictor responsiveness was assessed by local delivery of norepinephrine (NE) via intradermal microdialysis. Skin blood flow was continuously monitored over each microdialysis membrane via laser-Doppler flowmetry. In protocol I, whole-body and local heating caused similar increases in cutaneous vascular conductance (CVC). The EC50 (log NE dose) of the dose-response curves for both whole body (-4.2 +/- 0.1 M) and local heating (-4.7 +/- 0.4 M) were significantly greater (i.e., high dose required to cause 50% reduction in CVC) relative to neutral skin temperature (- 5.6 +/- 0.0 M; P<0.05 for both). In both local and whole-body heated conditions CVC did not return to pre-heating values even at the highest dose of NE. In protocol II, calculated EC50 for 34, 37, 40, and 42 degrees C local heating was - 5.5 +/- 0.4, -4.6 +/- 0.3, -4.5 +/- 0.3, - 4.2 +/- 0.4 M, respectively. Statistical analyses revealed that the EC50 for 37,40 and 42 degrees C were significantly greater than the EC50 for 34 degrees C. These results indicate that even during administration of high concentrations of NE, alpha-adrenergic vasoconstriction does not fully compensate for local heating and whole-body heating induced vasodilatation in young, healthy subjects. Moreover, these data suggest that elevated local temperatures, above 37 degrees C, and whole-body heating similarly attenuate cutaneous alpha-adrenergic vasoconstriction responsiveness.

Wilson, Thad E.; Cui, Jian; Crandall, Craig G.

2002-01-01

80

Heat production of rat anococcygeus muscle during isometric contraction.  

PubMed

Heat production, unloaded shortening velocity (Vus), and load-bearing capacity (LBC) were studied in the isolated rat anococcygeus muscle during isometric contractions at 27 degrees C. The relation between the total suprabasal heat produced and the stress-time integral for isometric contractions of various durations was curvilinear, demonstrating a decreasing slope as contractile duration increased. The rate of heat production at 600 s was approximately 68% of the peak value of 6.55 mW/g that occurred at 10 s. At the same time, force rose from a mean of 92 mN/mm2 at 10 s to a value of 140 mN/mm2 at 600 s. This produced a nearly threefold increase in the economy of force maintenance. The decline in the rate of heat production was accompanied by a decline in Vus from 0.56 Lo/s at 10 s to 0.28 Lo/s at 600 s, where Lo is the length for optimal force development. This suggests the fall in the rate of heat production was caused, at least in part, by a slowing of cross-bridge kinetics. The ratio of LBC to developed tension at 10 s was not significantly different from the ratio at 600 s, suggesting that the increase in tension was due to an increased number of attached cross bridges. The decline in heat production, therefore, appears contradictory, since an increased number of attached cross bridges would predict an increased rate of energy expenditure. The observations can be reconciled if either 1) the increase in force is caused by a progressive increase in the attachment time of a constant number of cross bridges that cycle at a lower frequency or 2) the decline in energy expenditure caused by the slowing of cross-bridge cycling is sufficient to mask the increase caused by the recruitment of additional cross bridges. PMID:3177627

Walker, J S; Wendt, I R; Gibbs, C L

1988-10-01

81

Indication of anomalous heat energy production in a reactor device  

E-print Network

An experimental investigation of possible anomalous heat production in a special type of reactor tube named E-Cat HT is carried out. The reactor tube is charged with a small amount of hydrogen loaded nickel powder plus some additives. The reaction is primarily initiated by heat from resistor coils inside the reactor tube. Measurement of the produced heat was performed with high-resolution thermal imaging cameras, recording data every second from the hot reactor tube. The measurements of electrical power input were performed with a large bandwidth three-phase power analyzer. Data were collected in two experimental runs lasting 96 and 116 hours, respectively. An anomalous heat production was indicated in both experiments. The 116-hour experiment also included a calibration of the experimental set-up without the active charge present in the E-Cat HT. In this case, no extra heat was generated beyond the expected heat from the electric input. Computed volumetric and gravimetric energy densities were found to be fa...

Levi, Giuseppe; Hartman, Torbjörn; Höistad, Bo; Pettersson, Roland; Tegnér, Lars; Essén, Hanno

2013-01-01

82

Indication of anomalous heat energy production in a reactor device  

E-print Network

An experimental investigation of possible anomalous heat production in a special type of reactor tube named E-Cat HT is carried out. The reactor tube is charged with a small amount of hydrogen loaded nickel powder plus some additives. The reaction is primarily initiated by heat from resistor coils inside the reactor tube. Measurement of the produced heat was performed with high-resolution thermal imaging cameras, recording data every second from the hot reactor tube. The measurements of electrical power input were performed with a large bandwidth three-phase power analyzer. Data were collected in two experimental runs lasting 96 and 116 hours, respectively. An anomalous heat production was indicated in both experiments. The 116-hour experiment also included a calibration of the experimental set-up without the active charge present in the E-Cat HT. In this case, no extra heat was generated beyond the expected heat from the electric input. Computed volumetric and gravimetric energy densities were found to be far above those of any known chemical source. Even by the most conservative assumptions as to the errors in the measurements, the result is still one order of magnitude greater than conventional energy sources.

Giuseppe Levi; Evelyn Foschi; Torbjörn Hartman; Bo Höistad; Roland Pettersson; Lars Tegnér; Hanno Essén

2013-06-07

83

Using Forecast and Observed Weather Data to Assess Performance of Forecast Products in Identifying Heat Waves and Estimating Heat Wave Effects on Mortality  

PubMed Central

Background: Heat wave and health warning systems are activated based on forecasts of health-threatening hot weather. Objective: We estimated heat–mortality associations based on forecast and observed weather data in Detroit, Michigan, and compared the accuracy of forecast products for predicting heat waves. Methods: We derived and compared apparent temperature (AT) and heat wave days (with heat waves defined as ? 2 days of daily mean AT ? 95th percentile of warm-season average) from weather observations and six different forecast products. We used Poisson regression with and without adjustment for ozone and/or PM10 (particulate matter with aerodynamic diameter ? 10 ?m) to estimate and compare associations of daily all-cause mortality with observed and predicted AT and heat wave days. Results: The 1-day-ahead forecast of a local operational product, Revised Digital Forecast, had about half the number of false positives compared with all other forecasts. On average, controlling for heat waves, days with observed AT = 25.3°C were associated with 3.5% higher mortality (95% CI: –1.6, 8.8%) than days with AT = 8.5°C. Observed heat wave days were associated with 6.2% higher mortality (95% CI: –0.4, 13.2%) than non–heat wave days. The accuracy of predictions varied, but associations between mortality and forecast heat generally tended to overestimate heat effects, whereas associations with forecast heat waves tended to underestimate heat wave effects, relative to associations based on observed weather metrics. Conclusions: Our findings suggest that incorporating knowledge of local conditions may improve the accuracy of predictions used to activate heat wave and health warning systems. Citation: Zhang K, Chen YH, Schwartz JD, Rood RB, O’Neill MS. 2014. Using forecast and observed weather data to assess performance of forecast products in identifying heat waves and estimating heat wave effects on mortality. Environ Health Perspect 122:912–918;?http://dx.doi.org/10.1289/ehp.1306858 PMID:24833618

Chen, Yeh-Hsin; Schwartz, Joel D.; Rood, Richard B.; O’Neill, Marie S.

2014-01-01

84

Optimization and heat and water integration for biodiesel production  

E-print Network

with the food chain and the high cost of the raw material requires focusing on alternative sources of oil. 10 is to simultaneously optimize and heat integrate the production of biodiesel from each of the different oil sources@cmu.edu (I.E. Grossmann) #12;2 1.-Introduccion Many researchers have concluded that vegetable oils hold

Grossmann, Ignacio E.

85

1. -HOUSING AND ENVIRONMENT Colostrum consumption, thermoregulation and heat production  

E-print Network

1. - HOUSING AND ENVIRONMENT Colostrum consumption, thermoregulation and heat production in newborn sur 1'Elevage des Porcs, Centre de Rennes-Saint-Gilles, F 35590 L'Hermitage Colostrum consumption.8 p. 100 more colostrum than at 18-20 °C (290 and 212 g/day, respectively). Similarly, rectal

Boyer, Edmond

86

Mechanism behind Unique Properties of Local Heating in Nanoscale Junctions  

NASA Astrophysics Data System (ADS)

We investigate the unique properties of current-induced heat generation in nanojunctions, such as failed Q ? I relation (where Q is the heat generation and I the current), threshold voltage required to generate heat, etc. By employing the lead-quantum dot (QD)-lead system, we find these unique properties stem from (i) the discontinuity of Fermi distribution at chemical potentials of the leads and (ii) the satellite peaks in spectral function of the QD electron, which are induced by the electron-phonon interaction. Supported by the National Natural Science Foundation of China under Grant No. 11164011 and the Provincial Nature Science Foundation of Jiangxi under Grant Nos. 20122BAB212006 and 20132BAB212003

Zhou, Li-Ling; Li, Yong-Jun; Yu, Li-Sheng

2015-03-01

87

Studies of local electron heat transport on TFTR  

SciTech Connect

The anomalously fast relaxation of the perturbations to the electron temperature profile caused by a sawtooth crash has been studied extensively on TFTR. We will show that on a short timescale the heat pulse is not simply diffusive as has been generally assumed, but that modeling of the heat pulse requires a transient enhancement in {chi}{sub e} following the sawtooth crash. It will be shown that the time-dependent enhancement in {chi}{sub e} predicted by non-linear thermal transport models, i.e., incremental {chi} models or the Rebut-Lallia-Watkins transport model, is much smaller than that required to explain the anomalies in the heat pulse propagation.

Fredrickson, E.D.; Chang, Z.Y.; Janos, A.; McGuire, K.M.; Scott, S.; Taylor, G.

1993-08-16

88

New technique of the local heat flux measurement in combustion chambers of steam boilers  

NASA Astrophysics Data System (ADS)

A new method for measurement of local heat flux to water-walls of steam boilers was developed. A flux meter tube was made from an eccentric tube of short length to which two longitudinal fins were attached. These two fins prevent the boiler setting from heating by a thermal radiation from the combustion chamber. The fins are not welded to the adjacent water-wall tubes, so that the temperature distribution in the heat flux meter is not influenced by neighbouring water-wall tubes. The thickness of the heat flux tube wall is larger on the fireside to obtain a greater distance between the thermocouples located inside the wall which increases the accuracy of heat flux determination. Based on the temperature measurements at selected points inside the heat flux meter, the heat flux absorbed by the water-wall, heat transfer coefficient on the inner tube surface and temperature of the water-steam mixture was determined.

Taler, Jan; Taler, Dawid; Sobota, Tomasz; Dzierwa, Piotr

2011-12-01

89

Alterations in heat loss and heat production mechanisms in rat exposed to hypergravic fields  

NASA Technical Reports Server (NTRS)

A review of studies investigating the thermal response of rats exposed to hypergravic fields well below maximum tolerance levels is presented. It is concluded that several lines of evidence indicate that the neural switching network for temperature regulation and cardiovascular channeling of blood flow is transiently affected during the first hour a rat is exposed to hypergravity. Moreover, even after one hour of exposure, when the core temperature has fallen several degrees, shivering and nonshivering thermogenesis are not fully activated. Only after prolonged exposure to hypergravic fields do heat production mechanisms recover sufficiently to bring the core temperature back to a normal level. Thus, the data indicate a more rapid recovery of effector mechanisms for heat loss than for heat production.

Horowitz, J. M.; Horwitz, B. A.; Oyama, J.

1982-01-01

90

Isothermalization for a Non-local Heat Equation Emmanuel Chasseigne  

E-print Network

In this paper we study the asymptotic behavior for a nonlocal heat equation in an inho- mogenous medium: (x in the whole space. 1 Introduction The aim of this paper is to study the asymptotic behavior for a nonlocal to infinity asymptotically as t . Organisation and main results We first prove in Section 2 a comparison

91

A local BIEM for analysis of transient heat conduction with nonlinear source terms in FGMs  

Microsoft Academic Search

The diffusion equation with nonlinear heat source intensity in functionally graded materials (FGMs) is considered. In FGMs the thermal material properties are dependent on spatial coordinates. For transient or steady-state heat problems in FGMs the conventional boundary integral equation method or boundary element method cannot be applied due to the lack of a fundamental solution. In this paper, a local

Jan Sladek; Vladimir Sladek; Ch. Zhang

2004-01-01

92

Transient heat conduction analysis in functionally graded materials by the meshless local boundary integral equation method  

Microsoft Academic Search

Advanced computational method for transient heat conduction analysis in continuously nonhomogeneous functionally graded materials (FGM) is proposed. The method is based on the local boundary integral equations with moving least square approximation of the temperature and heat flux. The initial-boundary value problem is solved by the Laplace transform technique. Both Papoulis and Stehfest algorithms are applied for the numerical Laplace

J. Sladek; V. Sladek; Ch. Zhang

2003-01-01

93

Enhancement of Localized Heating by Ultrasonically Induced Cavitation in High Intensity Focused Ultrasound Treatment  

Microsoft Academic Search

There are reports that ultrasonically induced cavitation bubbles locally enhance tissue heating in high intensity focused ultrasound (HIFU) treatment. In this study, a high-intensity burst (named ``a triggering pulse'') above the cavitation threshold was used to trigger cavitation. Immediately after that, CW ultrasound (named ``heating waves''), at an intensity level and duration typical for conventional HIFU ablation was irradiated. Before

Ryo Takagi; Shin Yoshizawa; Shin-ichiro Umemura

2010-01-01

94

Local Heating of Discrete Droplets Using Magnetic Porous Silicon-Based Photonic Crystals  

E-print Network

Local Heating of Discrete Droplets Using Magnetic Porous Silicon-Based Photonic Crystals Ji-Ho Park (FRET). The magnetic porous Si microparticles were prepared as photonic crystals, containing spectral surrounding the experiment) generates heat in the superpara- magnetic particles that can raise the temperature

Bhatia, Sangeeta

95

Inverse estimation of the local heat transfer coefficient in curved tubes: a numerical validation  

NASA Astrophysics Data System (ADS)

Wall curvature represents one of the most used passive techniques to enhance convective heat transfer. The effectiveness of wall curvature is due to the fact that it gives origin to the centrifugal force: this phenomenon induces local maxima in the velocity distribution that locally increase the temperature gradients at the wall by then maximizing the heat transfer. This fact brings to a significant variation of the wall temperature and of the wall heat flux along the circumferential coordinate. The convective heat transfer coefficient is consequently not uniformly distributed along the tube's perimeter and is characterized by higher values at the extrados wall surface in comparison to the ones at the intrados wall surface. Therefore, for predicting the overall performance of heat transfer apparatuses that involve the use of curved tubes, it becomes important to know the local distribution of the convective heat transfer coefficient not only along the axis of the heat transfer section, but also on the internal tube's surface along the cross section circumference. The present paper is intended to the assessment of a procedure developed to evaluate the local convective heat transfer coefficient, along the circumferential coordinate, at the internal wall of a coiled pipe.

Bozzoli, F.; Cattani, L.; Corradi, C.; Mordacci, M.; Rainieri, S.

2014-04-01

96

Remotely actuated localized pressure and heat apparatus and method of use  

NASA Technical Reports Server (NTRS)

Apparatus and method for the use of a remotely actuated localized pressure and heat apparatus for the consolidation and curing of fiber elements in, structures. The apparatus includes members for clamping the desired portion of the fiber elements to be joined, pressure members and/or heat members. The method is directed to the application and use of the apparatus.

Merret, John B. (Inventor); Taylor, DeVor R. (Inventor); Wheeler, Mark M. (Inventor); Gale, Dan R. (Inventor)

2004-01-01

97

Local convective heat transfer from a horizontal tube in an acoustic cavitation field  

Microsoft Academic Search

An experiment has been carried out to investigate the local convective heat transfer from a horizontal circular copper tube\\u000a in an acoustic cavitation field. The effects of acoustical parameters (including sound source intensity, the vibrator location\\u000a and sound distance), fluid temperature and thermophysical properties of working fluid on heat transfer enhancement were studied,\\u000a as well as the variation of heat

Dingwei Zhou; Xuegong Hu; Dengying Liu

2004-01-01

98

Observation of localized heating phenomena during microwave heating of mixed powders using in situ x-ray diffraction technique  

SciTech Connect

In materials processing research using microwave heating, there have been several observations of various phenomena occurring known as microwave effects. One significant example of such a phenomenon is increased reaction kinetics. It is believed that there is a possibility that this might be caused by localized heating, were some reactants would attain a higher than apparent temperature. To examine whether such thermal gradients are indeed possible, mixed powders of two microwave non-absorbers, alumina and magnesia, were mixed with graphite, a known absorber, and heated in a microwave furnace. During microwave irradiation, the local temperatures of the respective sample constituents were measured using an in situ x-ray diffraction technique. In the case of the alumina and graphite sample, a temperature difference of around 100?°C could be observed.

Sabelström, N., E-mail: sabelstrom.n.aa@m.titech.ac.jp; Hayashi, M. [Department of Metallurgy and Ceramics Science, Tokyo Institute of Technology, Tokyo 152-8552 (Japan); Watanabe, T. [Department of Chemistry and Materials Science, Tokyo Institute of Technology, Tokyo 152-8552 (Japan); Nagata, K. [Department of Conservation Science, Tokyo University of the Arts, 12-8 Ueno Park, Taito-ku, Tokyo (Japan)

2014-10-28

99

Localized induction heating solder bonding for wafer level MEMS packaging  

NASA Astrophysics Data System (ADS)

This paper reports a new solder bonding method for the wafer level packaging of MEMS devices. Electroplated magnetic film was heated using induction heating causing the solder to reflow. The experiment results show that it took less than 1 min to complete the bonding process. In addition, the MEMS devices experienced a temperature of only 110 °C during bonding, thus thin film materials would not be damaged. Moreover, the bond strength between silicon and silicon wafer was higher than 18 MPa. The step height of the feed-through wire (acting as the electrical feed-through of the bonded region) is sealed by the electroplated film. Thus, the flatness and roughness of the electroplated surface are recovered by the solder reflow, and the package for preventing water leakage can be achieved. The integration of the surface micromachined devices with the proposed packaging techniques was demonstrated.

Yang, Hsueh-An; Wu, Mingching; Fang, Weileun

2005-02-01

100

Quality assessment of palm products upon prolonged heat treatment.  

PubMed

Extending the frying-life of oils is of commercial and economic importance. Due to this fact, assessment on the thermal stability of frying oils could provide considerable savings to the food processors. In this study, the physico-chemical properties of five palm products mainly palm oil, single-fractionated palm olein, double-fractionated palm olein, red palm olein and palm-based shortening during 80 hours of heating at 180 degrees C were investigated. Heating properties of these products were then compared with that of high oleic sunflower oil, which was used as reference oil. The indices applied in evaluating the quality changes of oils were free fatty acid, smoke point, p-anisidine value, tocols, polar and polymer compounds. Three palm products i.e. palm oil, single-fractionated palm olein and double-fractionated palm olein were identified to be the most stable in terms of lower formation of free fatty acid, polar and polymer compounds as well as preserving higher smoke point and tocols content compared to the other three oils. The low intensity of hydrolytic and oxidative changes due to prolonged heating, suggests that these palm products are inherently suitable for frying purposes. PMID:19001776

Tarmizi, Azmil Haizam Ahmad; Lin, Siew Wai

2008-01-01

101

Cultural and environmental factors governing tomato production: Local food production under elevated temperature conditions  

Technology Transfer Automated Retrieval System (TEKTRAN)

Long-term fresh tomato (Solanum lycopersicum L.) production data was used to estimate cultural and environmental impacts on marketable tomato yields in eastern Oklahoma. Quantifying the interactive effects of planting date and growing season duration and the effects of cumulative heat units and heat...

102

Non-local heat transport in Alcator C-Mod ohmic L-mode plasmas  

E-print Network

Non-local heat transport experiments were performed in Alcator C-Mod ohmic L-mode plasmas by inducing edge cooling with laser blow-off impurity (CaF2) injection. The non-local effect, a cooling of the edge electron temperature ...

Gao, Chi

103

Phenomenon of Coolant Local Natural Circulation Occurring in Heat Removal Loops of Nuclear Power Plant  

Microsoft Academic Search

The paper presents the results of experimental research performed at the BN-350 NPP, which have allowed the identification of a local natural circulation phenomenon arising in some sections of the NPP heat removal loops. The nature of this phenomenon and the features of its interaction with a total-circuit natural circulation are described. Also, the possible influence of the local natural

Yury ASHURKO; Gennady PUGACHEV

2011-01-01

104

Development of a locally-electron-heated plasma source for HDP-CVD process  

Microsoft Academic Search

A new ECR plasma source has been developed. ECR regions are produced locally by permanent magnets placed around the chamber. Microwaves enter the chamber through the side. Electrons are produced and heated in the local ECR regions near the microwave ports. The high energy electrons diffuse into the chamber where a cusp magnetic field is formed. Plasma produced by the

H. Seki; Y. Ueno; S. Ichimura; S. Takemori; S. Uchikawa; H. Murakamia; S. Okada; Y. Mochizuki; E. Setoyama

1998-01-01

105

Thermal conductivity in nanostructured materials and analysis of local angle between heat fluxes  

NASA Astrophysics Data System (ADS)

The phonon Boltzmann transport equation with the frequency-dependent model is solved numerically to study the thermal conductivity in nanoporous thin film and nanocomposite. Local angle between heat fluxes, defined as the angle between the directions of heat flux component qx and the local heat flux q, is introduced. At a fixed porosity or interface area, the thermal conductivity, local angle distribution, and the average angle of the two-dimensional nanoporous thin films with circular, hexagonal, square, and triangular pores are reported, and the thermal conductivity decreases with the increase in the interface area or porosity. Furthermore, the relationship between the thermal conductivity and average angle is also discussed for the three-dimensional nanoporous thin films with aligned or staggered pores, and silicon-germanium embedded and compacted nanocomposites. All the results show that the nanostructured material with a larger average angle between heat fluxes has a lower thermal conductivity.

Fu, B.; Tang, G. H.; Bi, C.

2014-09-01

106

Measurement of local connective heat transfer coefficients of four ice accretion shapes  

NASA Technical Reports Server (NTRS)

In the analytical study of ice accretions that form on aerodynamic surfaces (airfoils, engine inlets, etc.) it is often necessary to be able to calculate convective heat transfer rates. In order to do this, local convective heat transfer coefficients for the ice accretion shapes must be known. In the past, coefficients obtained for circular cylinders were used as an approximation to the actual coefficients since no better information existed. The purpose of this experimental study was to provide local convective heat transfer coefficients for four shapes that represent ice accretions. The shapes were tested with smooth and rough surfaces. The experimental method chosen was the thin-skin heat rate technique. Using this method local Nusselt numbers were determined for the ice shapes. In general it was found that the convective heat transfer was higher in regions where the model's surfaces were convex and lower in regions where the model's surfaces were concave. The effect of roughness was to increase the heat transfer in the high heat transfer regions by approximately 100% while little change was apparent in the low heat transfer regions.

Smith, M. E.; Armilli, R. V.; Keshock, E. G.

1984-01-01

107

Monodisperse magnetofluorescent nanoplatforms for local heating and temperature sensing  

NASA Astrophysics Data System (ADS)

Monodisperse multifunctional MnFe2O4/dye/silica core/shell nanoparticles have been designed and developed. The magnetic cores act as nano-heaters in biological systems under RF field excitation and the encapsulated dyes work as local temperature probes. The silica shells enable the water-solubility and biocompatibility of the NPs and protect the encapsulated fluorophores from photobleaching.Monodisperse multifunctional MnFe2O4/dye/silica core/shell nanoparticles have been designed and developed. The magnetic cores act as nano-heaters in biological systems under RF field excitation and the encapsulated dyes work as local temperature probes. The silica shells enable the water-solubility and biocompatibility of the NPs and protect the encapsulated fluorophores from photobleaching. Electronic supplementary information (ESI) available: The synthesis, characterization, and oxidation rates of Fe and Fe/SiO2 NPs. See DOI: 10.1039/c4nr04884a

Zhang, H.; Huang, H.; He, S.; Zeng, H.; Pralle, A.

2014-10-01

108

Grate-firing of biomass for heat and power production  

Microsoft Academic Search

As a renewable and environmentally friendly energy source, biomass (i.e., any organic non-fossil fuel) and its utilization are gaining an increasingly important role worldwide. Grate-firing is one of the main competing technologies in biomass combustion for heat and power production, because it can fire a wide range of fuels of varying moisture content, and requires less fuel preparation and handling.

Chungen Yin; Lasse A. Rosendahl; Søren K. Kær

2008-01-01

109

Monodisperse magnetofluorescent nanoplatforms for local heating and temperature sensing.  

PubMed

Monodisperse multifunctional MnFe2O4/dye/silica core/shell nanoparticles have been designed and developed. The magnetic cores act as nano-heaters in biological systems under RF field excitation and the encapsulated dyes work as local temperature probes. The silica shells enable the water-solubility and biocompatibility of the NPs and protect the encapsulated fluorophores from photobleaching. PMID:25308371

Zhang, H; Huang, H; He, S; Zeng, H; Pralle, A

2014-11-21

110

Development of a locally electron-heated plasma source  

Microsoft Academic Search

A new type high-density plasma source has been developed. It employs a 2.45-GHz microwave in combination with permanent magnets which surround microwave ports located in the chamber sidewall. Electron–cyclotron resonance regions are formed locally in front of the microwave ports. High-energy electrons are produced which diffuse into the center of the chamber along the lines of magnetic force. A cusp

H. Seki; S. Kitazawa; Y. Ueno; N. Wada; S. Takemori; T. Sato; S. Uchikawa; E. Setoyama

2000-01-01

111

Local nanoscale heating modulates single-asperity friction.  

PubMed

We demonstrate measurement and control of single-asperity friction by using cantilever probes featuring an in situ solid-state heater. The heater temperature was varied between 25 and 650 °C (tip temperatures from 25 ± 2 to 120 ± 20 °C). Heating caused friction to increase by a factor of 4 in air at ? 30% relative humidity, but in dry nitrogen friction decreased by ? 40%. Higher velocity reduced friction in ambient with no effect in dry nitrogen. These trends are attributed to thermally assisted formation of capillary bridges between the tip and substrate in air, and thermally assisted sliding in dry nitrogen. Real-time friction measurements while modulating the tip temperature revealed an energy barrier for capillary condensation of 0.40 ± 0.04 eV but with slower kinetics compared to isothermal measurements that we attribute to the distinct thermal environment that occurs when heating in real time. Controlling the presence of this nanoscale capillary and the associated control of friction and adhesion offers new opportunities for tip-based nanomanufacturing. PMID:20929204

Greiner, Christian; Felts, Jonathan R; Dai, Zhenting; King, William P; Carpick, Robert W

2010-11-10

112

Hanford production reactor heat releases 1951--1971  

SciTech Connect

The purpose of this report is to document and detail the thermal releases from the Hanford nuclear production reactors during the period 1951 through 1971, and to put these releases in historical perspective with respect to changing Columbia River flows and temperatures. This information can also be used as a foundation for further ecological evaluations. When examining Hanford production reactor thermal releases to the Columbia River all related factors affecting the releases and the characteristics of the river should be considered. The major considerations in the present study were the characteristics of the releases themselves (primarily coolant flow rate, temperatures, discharge facilities, period of operation, and level of operation) and the characteristics of the river in that reach (primarily flow rate, temperature and mixing characteristics; the effects of dam construction were also taken into account). In addition, this study addressed ecological effects of thermal releases on aquatic species. Accordingly, this report includes discussion of the reactor cooling system, historical heat releases, thermal mixing and transport studies, hydroelectric power development, and ecologic effects of Hanford production reactor heat releases on salmon and trout. Appendix A contains reactor operating statistics, and Appendix B provide computations of heat added to the Columbia River between Priest Rapids Dam and Richland, Washington.

Kannberg, L.D.

1992-04-01

113

Fundamental Study of Local Heat Transfer in Forced Convective Boiling of Ammonia on Vertical Flat Plate  

NASA Astrophysics Data System (ADS)

In the present study, the fundamental experiments that investigate characteristics of local heat transfer in forced convective boiling on vertical flat plate with 2-mm channel height are taken to realize plate type compact evaporator for OTEC or STEC. The experiments are performed with ammonia as the working fluid. The experiments are also carried out with the following test conditions; saturated pressure = 0.7, 0.8, 0.9 MPa, mass flux = 7.5, 10, 15 kg/(m2•s), heat flux = 15, 20, 25 kW/m2 and inlet quality = 0.1 ~ 0.4 [-]. The result shows that the wall superheated temperature of forced convective boiling is lower than that of pool boiling. And the heat transfer coefficient increases with an increase in quality and the decrease in the local heat flux and saturated pressure for prescribed experimental conditions. However, local heat transfer coefficients are not affected by mass fluxes in the prescribed experimental conditions. An empirical correlation that can predict the local heat transfer coefficient on vertical flat plate within experimental conditions is also proposed.

Kim, Jeong-Hun; Arima, Hirofumi; Ikegami, Yasuyuki

114

Birch's Crustal Heat Production-Heat Flow Law: Key to Quantifying Mantle Heat Flow as a function of time  

NASA Astrophysics Data System (ADS)

Birch (1968) first showed the linear correlation of surface heat flow and radioactive heat production (Qs = Qo + bAs ) in granites in New England, USA and discussed implications to the vertical scale of radioactive heat generation in the crust. Subsequently similar relationships have been found worldwide and numerous papers written describing more details and expanding the implications of Birch's Law. The results are a powerful contribution from heat flow research to the understanding of the lithosphere and its evolution. Models are both well constrained experimentally and simple in implications. However, there still exist thermal models of the crust and lithosphere that do not have the same firm foundation and involve unnecessary ad hoc assumptions. A main point of confusion has been that the several of the original relationships were so low in error as to be considered by some to be "fortuitous". Interestingly a "similar" relationship has been proposed based on regional scale averaging of Qs -As data. A second point of confusion is that one admissible crustal radioactivity distribution model (the constant heat generation to depth b) has been criticized as unrealistic for a number of reasons, including the effect of erosion. However, it is appropriate to refer to the Qs -As relationship as a law because in fact the relationship holds as long as the vertical distribution is "geologically realistic." as will be demonstrated in this paper. All geologic and geophysical models of the continental crust imply decreasing heat production as a function of depth (i.e. the seismic layering for example) except in very special cases. This general decrease with depth is the only condition required for the existence of a "linear" Qs -As relationship. A comparison of all the Qs -As relationships proposed for terrains not affected by thermal events over the last 150 to 200 Ma shows a remarkably uniformity in slope (10 ± 3 km) and intercept value (30 ± 5 mWm-2 ). Therefore these parameters of Birch's Law equation represent the starting place for discussions of lithospheric thermal regime and evolution. The stability of the values of intercept Qo for areas with thermal ages of Paleozoic and older prove that the lithosphere heat flow does not vary significantly with age as is demonstrated in the companion paper. The minimum mantle heat flow for preMesozoic thermal terrains is 20 - 25 mWm-2. This value is consistent with the lack of indication from xenolith data that lithosphere thickness changes with age and with theoretical models of mantle convection.

Blackwell, D. D.; Thakur, M.

2007-12-01

115

77 FR 74027 - Certain Integrated Circuit Packages Provided with Multiple Heat-Conducting Paths and Products...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Certain Integrated Circuit Packages Provided with Multiple Heat- Conducting Paths and Products Containing Same; Commission...of certain integrated circuit packages provided with multiple heat-conducting paths and products containing same by reason...

2012-12-12

116

78 FR 63410 - Energy Conservation Program for Consumer Products: Test Procedures for Direct Heating Equipment...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Conservation Program for Consumer Products: Test Procedures for Direct Heating Equipment...of Energy (DOE) proposes to revise its test procedures for direct heating equipment...DOE's statutory obligation to review its test procedures for covered products at...

2013-10-24

117

Simulation of the heat-and-mass transfer in the mound of stored biological product with centers of spontaneous heating  

NASA Astrophysics Data System (ADS)

The mathematical model of the interdependent heat-and-mass transfer in a mound of stored biological product in view of the centers of spontaneous heating is offered. The finite-element solution was developed. The heat-and-moisture analysis of the mound was carried out making possible determining the optimum storage procedure.

Kondrashov, V. I.; Tyukov, V. M.

2006-12-01

118

Localized heating\\/bonding techniques in MEMS packaging  

Microsoft Academic Search

Packaging is used to protect and enable intelligent sensor systems utilized in manned\\/unmanned ground vehicle systems\\/subsystems. Because Micro electro mechanical systems (MEMS) are used often in these sensor or actuation products, it must interact with the surrounding environment, which may be in direct conflict with the desire to isolate the electronics for improved reliability\\/durability performance. For some very simple devices,

J. R. Mabesa Jr.; A. J. Scott; X. Wu; G. W. Auner

2005-01-01

119

Measurements of the local convective heat flux in turbulent Rayleigh-Bnard convection X.-D. Shang,1,2  

E-print Network

Measurements of the local convective heat flux in turbulent Rayleigh-Bénard convection X.-D. Shang convective heat transport in turbulent thermal convection is carried out in small-aspect-ratio cells filled with water. The local convective heat flux is obtained from the simultaneous velocity and temperature

Tong, Penger

120

Integrated bioenergy complex for the production of power, heat and bio-ethanol  

SciTech Connect

In this paper an integrated bioenergy complex for the production of power, heat and bio-ethanol is presented. Ethanol, in fact, has been recognized as a high-quality transportation fuel. The reduction of petroleum consumption, especially for transport, is a strategic goal especially for those countries that already have or will experience an intensive industrial development in the next future. For these motivations, the production of bio-ethanol from Sweet Sorghum (which is now one of the most promising crop for this application in term of productivity, inputs demand, and flexibility) is of great interest in most of countries. The proposed integrated complex produces power, heat and bio-ethanol: the produced power and heat are partly used for bio-ethanol processing and biomass pre-treatment, partly to be sold to the market. This system has important innovations allowing a decentralized energy and ethanol production and creating new local jobs. The small power plant is based upon a steam cycle with an advanced low emission combustor, capable of burning different biomass resources with a modest decrease in the efficiency value. The Bioenergy Complex, suitable to satisfy the needs of a 3,000 inhabitants village, is composed by the following sub-systems: (1) Sweet Sorghum plantation (250 ha); the main products are: dry bagasse (approximately 3,900 Ton/year), grains (1,300 Ton/y) and sugar (1,850 Ton/y); (2) Cane crushing--sugar juice extraction system; (3) Sugar juice fermentation and distillation ethanol production (approx. 835 Ton/y); (4) Biomass pre-treatment components (grinding, drying, briquetting, storage, etc.); and (5) Cogeneration unit--the expansion unit is constituted by a last generation reciprocating steam engine, coupled with a 500 kWe alternator; the heat of the expanded flow is removed in the condenser, with an available thermal power of approximately 2,000 kWt.

Taviani, M.; Chiaramonti, D.; Tondi, G.; Grassi, G.

1998-07-01

121

Heat conduction in nanoscale materials: a statistical-mechanics derivation of the local heat flux.  

PubMed

We derive a coarse-grained model for heat conduction in nanoscale mechanical systems. Starting with an all-atom description, this approach yields a reduced model, in the form of conservation laws of momentum and energy. The model closure is accomplished by introducing a quasilocal thermodynamic equilibrium, followed by a linear response approximation. Of particular interest is the constitutive relation for the heat flux, which is expressed nonlocally in terms of the spatial and temporal variation of the temperature. Nanowires made of copper and silicon are presented as examples. PMID:25314400

Li, Xiantao

2014-09-01

122

The Heat is On: Understanding Local Climate Change  

NSDL National Science Digital Library

The is a curriculum module from the project Data Sets and Inquiry in Geoscience Education (DIGS). The module consists of a week-long unit and two-day performance assessment in which students apply the inquiry skills to problem-based investigations of urban micro-climates. The unit and performance assessment present semi-parallel tasks but about different cities (Phoenix and Chicago). Sudents draw conclusions about the extent to which multiple decades of temperature data about Phoenix suggest that a shift in local climate is taking place as opposed to exhibiting nothing more than natural variability. The data are from the Global Climate Historical Network (GHCN) database. GHCN is a large, multi-year, international project to measure temperature, precipitation, and air pressure from near the ground. Each monthly maximum and minimum temperature is the highest and lowest temperature reading for the month, measured in Celsius. In Phoenix and in most other places, the temperature data are collected at local airports. The performance assessment for this module requires that students apply the methods and findings from the investigation of the climate data for Phoenix to climate data for Chicago. The Chicago data shows less evidence of trends in temperature change, and this is most evident comparing the night-time minimum temperature fluctuations between the two cities. Chicago also exhibits less increase in urban development and population growth than does Phoenix. In contrast to the curriculum unit, which primarily uses constructed-response tasks to encourage student explanation and discussion, the climate assessment tasks pose explicit selected- and constructed-response questions to ensure that the items elicit the intended thinking and hence provide evidence of the targeted standards-aligned skills and understandings.

Dan Zalles

123

Intracellular Localization of Heat Shock Proteins in Maize 1  

PubMed Central

The intracellular distribution of the maize root heat shock proteins (hsp) was studied as a step toward understanding their physiological function. Linear sucrose density centrifugation was employed to separate organelles so the relative quantities of hsp in different subcellular compartments could be analyzed in a single preparation. Gradient fractions were assayed for the presence of hsp by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and for marker enzyme activities. Analyses of 15 to 60% gradients showed five hsp to be organelle associated. Hsp 25 and 72 were in fractions containing closely equilibrating Golgi and endoplasmic reticulum marker activities, while hsp 18, 29, and 72 were in fractions containing overlapping plasma membrane, mitochondria, and glyoxysomal marker activities. Hsp larger than 72 kilodaltons were not present in gradient fractions. A second fractionation scheme achieved better separation of the two sets of closely equilibrating organelles. When a 13,000g centrifugation step to remove mitochondria was employed prior to gradient centrifugation, hsp 29 was absent from the gradient fractions. If the buoyant density of the endoplasmic reticulum was shifted by either maintaining the ribosomes on the membrane or removing them, a corresponding shift in the equilibrium positions of hsp 25 and 72 occurred. Hsp 18 and 70 remained in plasma membrane-containing fractions irrespective of these treatments. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:16665584

Cooper, Pam; Ho, Tuan-Hua David

1987-01-01

124

Information technology, efficiency and productivity: evidence from Korean local governments  

Microsoft Academic Search

This study evaluates the performance of Korean local government by measuring their technical efficiency (TE) and total factor productivity (TFP) growth and, more importantly, examining the impact of information technology (IT) on this performance. The study is different from received analysis in that a unique measure of the state of IT–the Informatization Index–is used to investigate the impact of IT

Nakil Sung

2007-01-01

125

Hydrogen production from coal using a nuclear heat source  

NASA Technical Reports Server (NTRS)

A strong candidate for hydrogen production in the intermediate time frame of 1985 to 1995 is a coal-based process using a high-temperature gas-cooled reactor (HTGR) as a heat source. Expected process efficiencies in the range of 60 to 70% are considerably higher than all other hydrogen production processes except steam reforming of a natural gas. The process involves the preparation of a coal liquid, hydrogasification of that liquid, and steam reforming of the resulting gaseous or light liquid product. A study showing process efficiency and cost of hydrogen vs nuclear reactor core outlet temperature has been completed, and shows diminishing returns at process temperatures above about 1500 F. A possible scenario combining the relatively abundant and low-cost Western coal deposits with the Gulf Coast hydrogen users is presented which provides high-energy density transportation utilizing coal liquids and uranium.

Quade, R. N.

1976-01-01

126

Elevated local skin temperature impairs cutaneous vasoconstrictor responses to a simulated haemorrhagic challenge while heat stressed.  

PubMed

During a simulated haemorrhagic challenge, syncopal symptoms develop sooner when individuals are hyperthermic relative to normothermic. This is due, in part, to a large displacement of blood to the cutaneous circulation during hyperthermia, coupled with inadequate cutaneous vasoconstriction during the hypotensive challenge. The influence of local skin temperature on these cutaneous vasoconstrictor responses is unclear. This project tested the hypothesis that local skin temperature modulates cutaneous vasoconstriction during simulated haemorrhage in hyperthermic humans. Eight healthy participants (four men and four women; 32 ± 7 years old; 75.2 ± 10.8 kg) underwent lower-body negative pressure to presyncope while heat stressed via a water-perfused suit sufficiently to increase core temperature by 1.2 ± 0.2 °C. At forearm skin sites distal to the water-perfused suit, local skin temperature was either 35.2 ± 0.6 (mild heating) or 38.2 ± 0.2 °C (moderate heating) throughout heat stress and lower-body negative pressure, and remained at these temperatures until presyncope. The reduction in cutaneous vascular conductance during the final 90 s of lower-body negative pressure, relative to heat-stress baseline, was greatest at the mildly heated site (-10 ± 15% reduction) relative to the moderately heated site (-2 ± 12%; P = 0.05 for the magnitude of the reduction in cutaneous vascular conductance between sites), because vasoconstriction at the moderately heated site was either absent or negligible. In hyperthermic individuals, the extent of cutaneous vasoconstriction during a simulated haemorrhage can be modulated by local skin temperature. In situations where skin temperature is at least 38 °C, as is the case in soldiers operating in warm climatic conditions, a haemorrhagic insult is unlikely to be accompanied by cutaneous vasoconstriction. PMID:22903981

Pearson, J; Lucas, R A I; Crandall, C G

2013-02-01

127

Solar production of intermediate temperature process heat, phase 1 design  

NASA Astrophysics Data System (ADS)

The system consists of 42,420 sq ft of parabolic trough, single axis tracking, concentrating solar collectors. The collectors are oriented in a North-South configuration and track East-West. A heat transfer fluid (Gulf Synfluid 4cs) is circulated in a closed loop fashion through the solar collectors and a series of heat exchangers. The inlet and outlet fluid temperatures for the collectors are 370 F and 450 F respectively. These temperatures are constantly maintained via a variable flow rate through the collectors (the flow rate varies in direct proportion to the level of insolation). Superheated steam is the final product of the solar energy system. Final steam quality at the steam generator is 420 F and 165 Psia.

1980-08-01

128

Self-generated Local Heating Induced Nanojoining for Room Temperature Pressureless Flexible Electronic Packaging  

PubMed Central

Metallic bonding at an interface is determined by the application of heat and/or pressure. The means by which these are applied are the most critical for joining nanoscale structures. The present study considers the feasibility of room-temperature pressureless joining of copper wires using water-based silver nanowire paste. A novel mechanism of self-generated local heating within the silver nanowire paste and copper substrate system promotes the joining of silver-to-silver and silver-to-copper without any external energy input. The localized heat energy was delivered in-situ to the interfaces to promote atomic diffusion and metallic bond formation with the bulk component temperature stays near room-temperature. This local heating effect has been detected experimentally and confirmed by calculation. The joints formed at room-temperature without pressure achieve a tensile strength of 5.7?MPa and exhibit ultra-low resistivity in the range of 101.3?nOhm·m. The good conductivity of the joint is attributed to the removal of organic compounds in the paste and metallic bonding of silver-to-copper and silver-to-silver. The water-based silver nanowire paste filler material is successfully applied to various flexible substrates for room temperature bonding. The use of chemically generated local heating may become a potential method for energy in-situ delivery at micro/nanoscale. PMID:25788019

Peng, Peng; Hu, Anming; Gerlich, Adrian P.; Liu, Yangai; Zhou, Y. Norman

2015-01-01

129

Self-generated Local Heating Induced Nanojoining for Room Temperature Pressureless Flexible Electronic Packaging.  

PubMed

Metallic bonding at an interface is determined by the application of heat and/or pressure. The means by which these are applied are the most critical for joining nanoscale structures. The present study considers the feasibility of room-temperature pressureless joining of copper wires using water-based silver nanowire paste. A novel mechanism of self-generated local heating within the silver nanowire paste and copper substrate system promotes the joining of silver-to-silver and silver-to-copper without any external energy input. The localized heat energy was delivered in-situ to the interfaces to promote atomic diffusion and metallic bond formation with the bulk component temperature stays near room-temperature. This local heating effect has been detected experimentally and confirmed by calculation. The joints formed at room-temperature without pressure achieve a tensile strength of 5.7?MPa and exhibit ultra-low resistivity in the range of 101.3?nOhm·m. The good conductivity of the joint is attributed to the removal of organic compounds in the paste and metallic bonding of silver-to-copper and silver-to-silver. The water-based silver nanowire paste filler material is successfully applied to various flexible substrates for room temperature bonding. The use of chemically generated local heating may become a potential method for energy in-situ delivery at micro/nanoscale. PMID:25788019

Peng, Peng; Hu, Anming; Gerlich, Adrian P; Liu, Yangai; Zhou, Y Norman

2015-01-01

130

Localized heating/bonding techniques in MEMS packaging  

NASA Astrophysics Data System (ADS)

Packaging is used to protect and enable intelligent sensor systems utilized in manned/unmanned ground vehicle systems/subsystems. Because Micro electro mechanical systems (MEMS) are used often in these sensor or actuation products, it must interact with the surrounding environment, which may be in direct conflict with the desire to isolate the electronics for improved reliability/durability performance. For some very simple devices, performance requirements may allow a high degree of isolation from the environment (e.g., stints and accelerometers). Other more complex devices (i.e. chemical and biological analysis systems, particularly in vivo systems) present extremely complex packaging requirements. Power and communications to MEMS device arrays are also extremely problematic. The following describes the research being performed at the U.S. Army Research, Development, and Engineering Command (RDECOM) Tank and Automotive Research, Development, and Engineering Center (TARDEC), in collaboration with Wayne State University, in Detroit, MI. The focus of the packaging research is limited to six main categories: a) provision for feed-through for electrical, optical, thermal, and fluidic interfaces; b) environmental management including atmosphere, hermiticity, and temperature; c) control of stress and mechanical durability; d) management of thermal properties to minimize absorption and/or emission; e) durability and structural integrity; and f) management of RF/magnetic/electrical and optical interference and/or radiation properties and exposure.

Mabesa, J. R., Jr.; Scott, A. J.; Wu, X.; Auner, G. W.

2005-05-01

131

Tissue-specific localization of heat-stress proteins during embryo development  

Microsoft Academic Search

We report on the stress-independent, tissue-specific expression of the heat-stress protein HSP17 in developing seeds of different plant species and on its intracellular localization. Though HSP17 expression during seed development seems to be a general phenomenon, the isoform patterns, the relative amounts in embryonic tissues and the intracellular localization show species-specific variations. In contrast to the results on the stressinduced

Uta zur Nieden; Dieter Neumann; Alexander Bucka; Lutz Nover

1995-01-01

132

Programmable mechanical resonances in MEMS by localized joule heating of phase change materials.  

PubMed

A programmable micromechanical resonator based on a VO2 thin film is reported. Multiple mechanical eigenfrequency states are programmed using Joule heating as local power source, gradually driving the phase transition of VO2 around its Metal-Insulator transition temperature. Phase coexistence of domains is used to tune the stiffness of the device via local control of internal stresses and mechanical properties. This study opens perspectives for developing mechanically configurable nanostructure arrays. PMID:24038351

Manca, Nicola; Pellegrino, Luca; Kanki, Teruo; Yamasaki, Syouta; Tanaka, Hidekazu; Siri, Antonio Sergio; Marré, Daniele

2013-11-26

133

Creating a Local Climate Product Using Composite Analysis  

NSDL National Science Digital Library

This Webcast features Heather Hauser of NOAA/ERH/SSD describing the utility of and introducing the methodology for conducting composite analysis as part of the NWS Climate Services program. This 30-minute presentation is intended to introduce climate focal points to the composite analysis process and will be a useful prerequisite to attending the Operational Climate Services residence courses, where the topic will be explored further. Composite analysis is the foundation of a forthcoming local climate-related product, the "3 Month Outlook of Local El Nino/La Nina Impacts."

COMET

2005-07-01

134

Investigations about the quantitative changes of carbon dioxide production in humans. Report 2: Carbon dioxide production during fever and its relationship with heat production  

NASA Technical Reports Server (NTRS)

Investigations are cited and explained for carbon dioxide production during fever and its relationship with heat production. The general topics of discussion are: (1) carbon dioxide production for alternating fever attacks; (2) heat balance during the perspiration phase; (3) heat balance during the chill phase; (4) the theory of fever; and (5) chill phase for other fever attacks.

Liebermeister, C.

1978-01-01

135

Urban Heat Islands and Their Mitigation vs. Local Impacts of Climate Change  

NASA Astrophysics Data System (ADS)

Urban heat islands and their mitigation take on added significance, both negative and positive, when viewed from a climate-change perspective. In negative terms, urban heat islands can act as local exacerbating factors, or magnifying lenses, to the effects of regional and large-scale climate perturbations and change. They can locally impact meteorology, energy/electricity generation and use, thermal environment (comfort and heat waves), emissions of air pollutants, photochemistry, and air quality. In positive terms, on the other hand, mitigation of urban heat islands (via urban surface modifications and control of man-made heat, for example) can potentially have a beneficial effect of mitigating the local negative impacts of climate change. In addition, mitigation of urban heat islands can, in itself, contribute to preventing regional and global climate change, even if modestly, by helping reduce CO2 emissions from power plants and other sources as a result of decreased energy use for cooling (both direct and indirect) and reducing the rates of meteorology-dependent emissions of air pollutants. This presentation will highlight aspects and characteristics of heat islands, their mitigation, their modeling and quantification techniques, and recent advances in meso-urban modeling of California (funded by the California Energy Commission). In particular, the presentation will focus on results from quantitative, modeling-based analyses of the potential benefits of heat island mitigation in 1) reducing point- and area-source emissions of CO2, NOx, and VOC as a result of reduced cooling energy demand and ambient/surface temperatures, 2) reducing evaporative and fugitive hydrocarbon emissions as a result of lowered temperatures, 3) reducing biogenic hydrocarbon emissions from existing vegetative cover, 4) slowing the rates of tropospheric/ground-level ozone formation and/or accumulation in the urban boundary layer, and 5) helping improve air quality. Quantitative estimates of the above will be presented based on recent and earlier meteorological, energy, thermal environmental, emissions, and photochemical modeling studies for California and Texas.

Taha, H.

2007-12-01

136

Differential Heat Shock Tolerance and Expression of Heat-Inducible Proteins in Two Stored-Product Psocids  

Microsoft Academic Search

The recent recognition of psocids as a major concern in stored products and also the reemergence of heat treatment as a control tactic of stored-product insects led to the present investigation. The objectives of this study were to determine whether there are differences in heat shock tolerance of two species of stored-product psocidsÑLepinotusreticulatus Enderlein (Trogiidae) and Liposcelis entomophila (Enderlein) (Liposcelididae)Ñand

R. N. C. GUEDES; K. Y. Zhu; G. P. Opit; J. E. Throne

2008-01-01

137

Laser production and heating of plasma for MHD application  

NASA Technical Reports Server (NTRS)

Experiments have been made on the production and heating of plasmas by the absorption of laser radiation. These experiments were performed to ascertain the feasibility of using laser-produced or laser-heated plasmas as the input for a magnetohydrodynamic (MHD) generator. Such a system would have a broad application as a laser-to-electricity energy converter for space power transmission. Experiments with a 100-J-pulsed CO2 laser were conducted to investigate the breakdown of argon gas by a high-intensity laser beam, the parameters (electron density and temperature) of the plasma produced, and the formation and propagation of laser-supported detonation (LSD) waves. Experiments were also carried out using a 1-J-pulsed CO2 laser to heat the plasma produced in a shock tube. The shock-tube hydrogen plasma reached electron densities of approximately 10 to the 17th/cu cm and electron temperatures of approximately 1 eV. Absorption of the CO2 laser beam by the plasma was measured, and up to approximately 100 percent absorption was observed. Measurements with a small MHD generator showed that the energy extraction efficiency could be very large with values up to 56 percent being measured.

Jalufka, N. W.

1988-01-01

138

Laser production and heating of plasma for MHD application  

SciTech Connect

Experiments have been made on the production and heating of plasmas by the absorption of laser radiation. These experiments were performed to ascertain the feasibility of using laser-produced or laser-heated plasmas as the input for a magnetohydrodynamic (MHD) generator. Such a system would have a broad application as a laser-to-electricity energy converter for space power transmission. Experiments with a 100-J-pulsed CO/sub 2/ laser were conducted to investigate the breakdown of argon gas by a high-intensity laser beam, the parameters (electron density and temperature) of the plasma produced, and the formation and propagation of laser-supported detonation (LSD) waves. Experiments were also carried out using a 1-J-pulsed CO/sub 2/ laser to heat the plasma produced in a shock tube. The shock-tube hydrogen plasma reached electron densities of approximately 10 to the 17th/cu cm and electron temperatures of approximately 1 eV. Absorption of the CO/sub 2/ laser beam by the plasma was measured, and up to approximately 100 percent absorption was observed. Measurements with a small MHD generator showed that the energy extraction efficiency could be very large with values up to 56 percent being measured.

Jalufka, N.W.

1988-03-01

139

Measurements of bremsstrahlung production and x-ray cryostat heating in VENUS  

SciTech Connect

The VENUS superconducting electron cyclotron resonance (ECR) ion source is designed to operate at 28 GHz with up to 10 kW of rf power. Most of this power is absorbed by the plasma electrons and then dumped onto the plasma chamber wall. The distribution of heating and bremsstrahlung production is highly nonuniform and reflects the geometry of the magnetic confinement fields. The nonuniform distribution of electron losses to the wall results in localized heating on the aluminum chamber walls, which can lead to burnout. In addition, part of the bremsstrahlung produced by the collision of the hot-electrons with the walls is absorbed by the cold mass of the superconducting magnet leading to an additional heat load in the cryostat in the order of several watts. Therefore a new plasma chamber has been installed that incorporates a high-Z tantalum shield to reduce the cryostat heating and enhance water cooling to minimize the chance of burnout. In order to better understand the heat load, the spectrum of the bremsstrahlung has been carefully measured as a function of rf power, magnetic confinement, and rf frequency. In addition, the distribution of electron heating in VENUS magnetic field has been simulated with a three-dimensional computer code [H. Heinen and H. J. Andra, Proceedings of the 14th International Workshop on ECR Sources (CERN, Geneva, 1999), 224; H. J. Andra and A. Heinen, Proceedings of the 15th International Workshop on ECR lon Sources, ECRIS'02 (Jyvaeskylae, Finland 2002), 85.] to better understand the heat load distribution on the plasma chamber wall. The new plasma chamber design, results of the bremsstrahlung measurements, and the effectiveness of the high-Z shielding are described.

Lyneis, C.; Leitner, D.; Todd, D.; Virostek, S.; Loew, T.; Heinen, A.; Tarvainen, O. [Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, California 94720 (United States); Institute of Nuclear Physics, Wilhelm-Klemm-Strasse, 9, D-48149, Muenster (Germany); Department of Physics (JYFL), FI-40014, University of Jyvaeskylae, Jyvaeskylae (Finland)

2006-03-15

140

Local Heat Flux Measurements with Single and Small Multi-element Coaxial Element-Injectors  

NASA Technical Reports Server (NTRS)

To support NASA's Vision for Space Exploration mission, the NASA Marshall Space Flight Center conducted a program in 2005 to improve the capability to predict local thermal compatibility and heat transfer in liquid propellant rocket engine combustion devices. The ultimate objective was to predict and hence reduce the local peak heat flux due to injector design, resulting in a significant improvement in overall engine reliability and durability. Such analyses are applicable to combustion devices in booster, upper stage, and in-space engines with regeneratively cooled chamber walls, as well as in small thrust chambers with few elements in the injector. In this program, single and three-element injectors were hot-fire tested with liquid oxygen and gaseous hydrogen propellants at The Pennsylvania State University Cryogenic Combustor Laboratory from May to August 2005. Local heat fluxes were measured in a 1-inch internal diameter heat sink combustion chamber using Medtherm coaxial thermocouples and Gardon heat flux gauges, Injector configurations were tested with both shear coaxial elements and swirl coaxial elements. Both a straight and a scarfed single element swirl injector were tested. This paper includes general descriptions of the experimental hardware, instrumentation, and results of the hot-fire testing for three coaxial shear and swirl elements. Detailed geometry and test results the for shear coax elements has already been published. Detailed test result for the remaining 6 swirl coax element for the will be published in a future JANNAF presentation to provide well-defined data sets for development and model validation.

Jones, Gregg; Protz, Christopher; Bullard, Brad; Hulka, James

2006-01-01

141

Optical investigation of heat release and NOx production in combustion  

NASA Astrophysics Data System (ADS)

Two novel optical techniques are presented for non-intrusive, spatially resolved study of combustion, both based on passive Optical Emission Tomography (OET). Firstly, OET is used for non-intrusive study of heat release through the detection of chemiluminescence by the hydroxyl radical that is generated in the burning process. The OET technique presented here is based on a passive fibre-optic detection system, which allows spatially resolved high-frequency detection of the flame front in a combustion flame, where all fibres detect the emission signals simultaneously. The system withstands the high pressures and temperatures typically encountered in the harsh environments of gas turbine combustors and IC engines. The sensor-array is non-intrusive, low-cost, compact, simple to configure and can be quickly set up around a combustion field. The maximum acquisition rate is 2 kHz. This allows spatially resolved study of the fast phenomena in combustion. Furthermore, a method is presented for study of the production of NOx through chemiluminescence from tri-methyl-borate (TMB). In combustion, the tri-methyl-borate produces green luminescence in locations where NOx would be produced. Combining the green luminescence visualisation with UV detection of the hydroxyl radical allows monitoring of heat release and of NOx production areas, thus giving a means of studying both the burning process and the resulting NOx pollution.

Timmerman, B. H.; Bryanston-Cross, P. J.

2007-10-01

142

Optical investigation of heat release and NOx production in combustion  

NASA Astrophysics Data System (ADS)

Two passive optical techniques are described to investigate combustion. Optical Emission Tomography (OET) is used for non-intrusive study of heat release through the detection of chemiluminescence by the hydroxyl radical that is generated in the burning process. The OET technique described here is based on a passive fibre-optic detection system, which allows spatially resolved high-frequency detection of the flame front in a combustion flame, where all fibres detect the emission signals simultaneously. The system withstands the high pressures and temperatures typically encountered in the harsh environments of gas turbine combustors and IC engines. The sensor-array is non-intrusive, low-cost, compact, simple to configure and can be quickly set up around a combustion field. The maximum acquisition rate is 2 kHz. This allows spatially resolved study of the fast phenomena in combustion. Furthermore, the production of NOx is investigated through the emission of green light as a result of adding tri-methyl-borate to a flame. In combustion, the tri-methyl-borate produces green luminescence in locations where NOx would be produced. Combining the green luminescence visualisation with OET detection of the hydroxyl radical allows monitoring of heat release and of NOx production areas, thus giving a means of studying both the burning process and the resulting NOx pollution.

Timmerman, B. H.; Patel, S.; Dunkley, P.; Bryanston-Cross, P. J.

2005-08-01

143

Identifying Biomass Sources for Localized Ethanol Production-- Remote Sensing Lesson  

NSDL National Science Digital Library

This remote sensing lesson from iGETT asks the question: "How can communities document local sources of biomass that can be used for energy production?" Students will use ArcGIS and ENVI software to develop a classified map that can be used to identify a source of biomass for energy production. The lesson will guide students through procedures for image processing, creating a vegetative index and identifying areas which have biomass materials. This resource from iGETT includes a learning unit summary, a student guide, supporting documentation and a data file. A quick, free registration is required to view or download any of the materials.

144

Computer simulation of pipe-bending processes with small bending radius using local induction heating  

Microsoft Academic Search

Through analyzing the stress state and deformation of pipe bending using local induction heating with small bending radius, a computer simulation system has been developed based on the FEM software ANSYS and finite strain elasto–plastic theory. The results, such as the thinning and thickening ratio of the pipe wall thickness, the pushing force with or without a reverse moment acting

Z Hu; J. Q Li

1999-01-01

145

Current profile tailoring using localized electron cyclotron heating in highly elongated TCV plasmas  

Microsoft Academic Search

Radially localized electron cyclotron heating (ECH) at the 2nd harmonic (X2) is used to tailor the current profile through the modification of the temperature, and hence conductivity, profiles. The optimal conditions for current profile broadening are investigated and applied to decrease the plasma internal inductance at constant plasma current. Highly elongated plasmas are thus created at low current, where they

Y. Camenen; F. Hofmann; A. Pochelon; A. Scarabosio; S. Alberti; G. Arnoux; P. Blanchard; S. Coda; T. P. Goodman; M. A. Henderson; E. Nelson-Melby; L. Porte; O. Sauter

2007-01-01

146

Rapid synthesis of carbon nanotubes by bulk and localized inductive heating  

Microsoft Academic Search

In this work, we report a rapid yet simple methodology for the synthesis of carbon nanotubes (CNTs) in a room temperature environment using an inductive heating system with either a) bulk synthesis on silicon chips, or b) local synthesis on suspended MEMS structures. This setup enables growth and integration of CNTs with MEMS structures in a matter of 1-2 minutes.

Brian D. Sosnowchik; Liwei Lin

2007-01-01

147

Local Boiling and Cavitation in Heat-Induced Counterflow of He II  

Microsoft Academic Search

Local boiling, cavitation, and cavitation collapse have been observed in the heat induced counter-flow of He II in a convergent-divergent nozzle. These observations are described and shown to be qualitatively and quantitatively in agreement with the two fluid equations supplemented by the Gorter-Mellink force.

James E. Broadwell; Hans W. Liepmann

1969-01-01

148

Integration of the fabrication processes and wafer level packaging of MEMS devices using localized induction heating  

Microsoft Academic Search

This paper reports a new method for the integration of fabrication processes and wafer level packaging of optical MEMS device. The electroplated magnetic thick film was employed to realize the localized heating assisted wafer level package. Due to the solder reflow and electroplating technique, hermetic seal of the packaged device is achieved. In addition, the electroplated thick film also performed

Hsuehan Yang; Mingching Wu; Weileun Fang

2003-01-01

149

Factors of Local Plasma Heating near a Target during Pulse Rise Time  

Microsoft Academic Search

Factors to heat plasmas during a rise time of pulse on the electrode covered by plasmas are explained. When pulse applies to the target, electrons with energy of several tens eV are detected at an early time. Different from secondary electrons, they can be measured only while sheath expands by a pulse rise and ionized locally near the target. They

Jae-Myung Choe; Gon-Ho Kim

2009-01-01

150

Local temperature redistribution and structural transition during joule-heating-driven conductance switching in VO2.  

PubMed

Joule-heating induced conductance-switching is studied in VO2 , a Mott insulator. Complementary in situ techniques including optical characterization, blackbody microscopy, scanning transmission X-ray microscopy (STXM) and numerical simulations are used. Abrupt redistribution in local temperature is shown to occur upon conductance-switching along with a structural phase transition, at the same current. PMID:23868142

Kumar, Suhas; Pickett, Matthew D; Strachan, John Paul; Gibson, Gary; Nishi, Yoshio; Williams, R Stanley

2013-11-13

151

Relations for local radiative heat transfer between rectangular boundaries of an absorbing-emitting medium  

NASA Technical Reports Server (NTRS)

An analytical solution was obtained by Siegel (1991, 1992) for local boundary heat fluxes by a radiating medium at uniform temperature in a 2D rectangular region. It is shown here that, after local fluxes from the medium to the walls have been evaluated, it is very easy to compute local fluxes arriving from the adjacent and opposite walls. This extends the previous analysis and provides convenient relations to include radiation from a black boundary, each side of the rectangle being at a different uniform temperature. The final expressions are helpful in performing spectral calculations that must be made for many spectral bands.

Siegel, R.

1993-01-01

152

Hybrid Quasicrystals, Transport and Localization in Products of Minimal Sets  

E-print Network

We consider convex combinations of finite-valued almost periodic sequences (mainly substitution sequences) and put them as potentials of one-dimensional tight-binding models. We prove that these sequences are almost periodic. We call such combinations {\\em hybrid quasicrystals} and these studies are related to the minimality, under the shift on both coordinates, of the product space of the respective (minimal) hulls. We observe a rich variety of behaviors on the quantum dynamical transport ranging from localization to transport.

Tulio O. Carvalho; Cesar R. de Oliveira

2007-06-12

153

Characterization of Heat Melt Compactor (HMC) Product Water  

NASA Technical Reports Server (NTRS)

The Heat Melt Compactor (HMC) is designed to sterilize and process wastes produced during space missions. Benefits of the HMC include reduction of biohazards to the crew, reduction in volume of wastes that would otherwise require storage, production of radiation shielding tiles, and recovery of water and other resources. Water reuse is critical onboard spacecrafts; it reduces the need for resupply missions and saves valuable storage space. The main sources of water in HMC batches are food, beverages, shampoo, disinfecting wipes, toothpaste, and diapers. Water reclaimed by the HMC was analyzed for concentrations of Na+, NH4+, K+, Mg2+, Ca2+, Cl-­-, NO2-­-, Br-­-, NO3-­-, PO43-­-, SO42-­-, total organic carbon (TOC), total inorganic carbon (TIC), % total solids, and pH. The data are discussed in relation to the current water input characteristics established for the International Space Station Water Processor Assembly system. Batches with higher than average amounts of food produced HMC product water with higher sulfate content, and batches with higher proportions of disinfectant wipes and food yielded HMC product water with higher ammonium concentration. We also compared theoretical chemical composition of HMC product water based on food labels and literature values to experimental results.

Harris, Linden; Wignarajah, Kanapathipi; Alba, Richard Gilbert; Pace, Gregory S.; Fisher, John W.

2013-01-01

154

Local Heat Transfer and CHF for Subcooled Flow Boiling - Annual Report 1993  

SciTech Connect

Subcooled flow boiling in heated coolant channels is an important heat transfer enhancement technique in the development of fusion reactor components, where high heat fluxes must be accommodated. As energy fluxes increase in magnitude, additional emphasis must be devoted to enhancing techniques such as sub cooling and enhanced surfaces. In addition to subcooling, other high heat flux alternatives such as high velocity helium and liquid metal cooling have been considered as serious contenders. Each technique has its advantages and disadvantages [1], which must be weighed as to reliability and reduced cost of fusion reactor components. Previous studies [2] have set the stage for the present work, which will concentrate on fundamental thermal hydraulic issues associated with the h-international Thermonuclear Experimental Reactor (ITER) and the Engineering Design Activity (EDA). This proposed work is intended to increase our understanding of high heat flux removal alternatives as well as our present capabilities by: (1) including single-side heating effects in models for local predictions of heat transfer and critical heat flux; (2) inspection of the US, Japanese, and other possible data sources for single-side heating, with the aim of exploring possible correlations for both CHF and local heat transfer; and (3) assessing the viability of various high heat flux removal techniques. The latter task includes: (a) sub-cooled water flow boiling with enhancements such as twisted tapes, and hypervapotrons, (b) high velocity helium cooling, and (c) other potential techniques such as liquid metal cooling. This assessment will increase our understanding of: (1) hypervapotron heat transfer via fins, flow recirculation, and flow oscillation, and (2) swirl flow. This progress report contains selective examples of ongoing work. Section II contains an extended abstract, which is part of and evolving technical paper on single-side f heating. Section III describes additional details which will be included in the first year of work. Section IV summarizes past and anticipated international interactions with investigators from other countries. Finally, Section V gives summaries of two conceptual experiments which are planned for the second and third years.

Dr. Ronald D. Boyd

2000-07-01

155

Energetic efficiency of cogeneration systems for combined heat, cold and power production  

Microsoft Academic Search

This paper deals with the problem of energetic efficiency evaluation of cogeneration systems for combined heat, cold and power production. Cogeneration systems have a large potential for energy saving, especially when they simultaneously produce heat, cold and power as useful energy flows. Various cogeneration systems for combined heat, cold and power production are designed by means of computer simulation to

V Havelský

1999-01-01

156

The Chemistry of Self-Heating Food Products: An Activity for Classroom Engagement  

ERIC Educational Resources Information Center

Two commercial self-heating food products have been used to apply chemical concepts such as stoichiometry, enthalpies of reactions and solutions, and heat transfer in a classroom activity. These products are the self-heating beverages sold in Europe and the Meals, Ready to Eat or MREs used primarily by the military in the United States. The main…

Oliver-Hoyo, Maria T.; Pinto, Gabriel; Llorens-Molina, Juan Antonio

2009-01-01

157

A Transport Model for Non-Local Heating of Electrons in ICP Reactors  

NASA Technical Reports Server (NTRS)

A new model has been developed for non-local heating of electrons in ICP reactors, based on a hydrodynamic approach. The model has been derived using the electron momentum conservation in azimuthal direction with electromagnetic and frictional forces respectively as driving force and damper of harmonic oscillatory motion of electrons. The resulting transport equations include the convection of azimuthal electron momentum in radial and axial directions, thereby accounting for the non-local effects. The azimuthal velocity of electrons and the resulting electrical current are coupled to the Maxwell's relations, thus forming a self-consistent model for non-local heating. This model is being implemented along with a set of Navier-Stokes equations for plasma dynamics and gas flow to simulate low-pressure (few mTorr's) ICP discharges. Characteristics of nitrogen plasma in a TCP 300mm etch reactor is being studied. The results will be compared against the available Langmuir probe measurements.

Chang, C. H.; Bose, Deepak; Arnold, James O. (Technical Monitor)

1998-01-01

158

Temperature distribution in tissues subjected to local hyperthermia by RF induction heating.  

PubMed

We have used a finite difference formulation of the bio-heat transfer equation to predict temperature distributions in and around a non-uniformly perfused volume located in layered tissue. Using available data on blood flow in experimental tumours we have shown that techniques capable of highly localized heating are required to treat small, well perfused tumours effectively. However, the r.f. technique considered here produces acceptable temperature distributions in larger tumours with poorly perfused centres. Skin cooling improves the effective penetration of the hyperthermal treatment and may improve the uniformity of heating. However, the considerable heat flux through superficial tissues associated with chilled water cooling can produce large temperature gradients in such regions. PMID:6950769

Hand, J W; Ledda, J L; Evans, T S

1982-03-01

159

A Fresnel collector process heat experiment at Capitol Concrete Products  

NASA Technical Reports Server (NTRS)

An experiment is planned, conducted and evaluated to determine the feasibility of using a Power Kinetics' Fresnel concentrator to provide process heat in an industrial environment. The plant provides process steam at 50 to 60 psig to two autoclaves for curing masonry blocks. When steam is not required, the plant preheats hot water for later use. A second system is installed at the Jet Propulsion Laboratory parabolic dish test site for hardware validation and experiment control. Experiment design allows for the extrapolation of results to varying demands for steam and hot water, and includes a consideration of some socio-technical factors such as the impact on production scheduling of diurnal variations in energy availability.

Hauger, J. S.

1981-01-01

160

Analysis of flow patterns in bubble and slurry bubble columns based on local heat transfer measurements  

Microsoft Academic Search

Flow patterns in two-phase (G–L) and three-phase (G–L–S) bubble columns are investigated based on local time-averaged heat transfer coefficients. The experiments are conducted in a 0.28m diameter Plexiglas column in air–water and air–water–glass beads (35?m) systems over superficial gas velocity range 0.05–0.3m\\/s and slurry concentration range 0–40vol.%. The heat transfer measurements are made with a specially designed probe which provided

H. Li; A. Prakash

2002-01-01

161

Inertial cavitation of microbubbles in ultrasound contrast agents: potential hazards of localized heating  

NASA Astrophysics Data System (ADS)

Microbubbles used as contrast agents in ultrasound diagnostics can undergo highly nonlinear oscillations under the influence of the driving sound pulses. We simulate the dynamics of inertially cavitating bubbles and show that a large part of the incident energy is re-emitted as sound at ultra-high frequencies. Its subsequent absorption and conversion into heat generates very high temperatures at micrometer distances from the bubble. The amount of energy deposited in blood or tissue is highly sensitive to the size distribution of the bubbles and to the amplitude of the driving pressure. We discuss the potential for harmful effects of the localized heating on the patient.

Hilgenfeldt, Sascha; Lohse, Detlef; Zomack, Michael

1999-11-01

162

Microwave heating as a new way to induce localized enhancements of reaction rate. Non-isothermal and heterogeneous kinetics  

Microsoft Academic Search

In this paper we investigate non-isothemal kinetic induced by microwave heating particularly in term of spatial distribution of temperature. We clearly show that it is possible by microwave heating to induce localized superheating (eventually thermal runaway in solid case) which lead to localized reaction rate enhancements.In this paper we investigate non-isothermal kinetics induced by microwave heating particularly in term of

D. Stuerga; P. Gaillard

1996-01-01

163

Light masking of circadian rhythms of heat production, heat loss, and body temperature in squirrel monkeys  

NASA Technical Reports Server (NTRS)

Whole body heat production (HP) and heat loss (HL) were examined to determine their relative contributions to light masking of the circadian rhythm in body temperature (Tb). Squirrel monkey metabolism (n = 6) was monitored by both indirect and direct calorimetry, with telemetered measurement of body temperature and activity. Feeding was also measured. Responses to an entraining light-dark (LD) cycle (LD 12:12) and a masking LD cycle (LD 2:2) were compared. HP and HL contributed to both the daily rhythm and the masking changes in Tb. All variables showed phase-dependent masking responses. Masking transients at L or D transitions were generally greater during subjective day; however, L masking resulted in sustained elevation of Tb, HP, and HL during subjective night. Parallel, apparently compensatory, changes of HL and HP suggest action by both the circadian timing system and light masking on Tb set point. Furthermore, transient HL increases during subjective night suggest that gain change may supplement set point regulation of Tb.

Robinson, E. L.; Fuller, C. A.

1999-01-01

164

Analysis of bubble dynamics and local hydrodynamics based on instantaneous heat transfer measurements in a slurry bubble column  

Microsoft Academic Search

A fast response heat transfer probe was designed to measure local instantaneous heat transfer coefficients at various gas velocities and slurry concentrations in a slurry bubble column. The enhancement of heat transfer due to turbulent bubble-wake region has been analyzed to understand bubble-wake dynamics. To quantitatively describe instantaneous heat transfer coefficient due to bubble-wake enhancement, a peak-fitting method was applied

H. Li; A. Prakash

1999-01-01

165

Measurements of local convective heat transfer coefficients on ice accretion shapes  

NASA Technical Reports Server (NTRS)

The thin-skin heat rate technique was used to determine local convective heat transfer coefficients for four representative ice accretion shapes. The shapes represented three stages of glaze ice formation and one rime ice formation; the ice models had varying degrees of surface roughness. In general, convective heat transfer was higher in regions where the model's surfaces were convex and lower in regions where the surfaces were concave. The effect of roughness was different for the glaze and rime ice shapes. On the glaze ice shapes, roughness increased the maximum Nu by 80 percent, but the other Nu values were virtually unchanged. On the rime ice shape, the Nu numbers near the stagnation point were unchanged. The maximum Nu value increased by 45 percent, and the Nu number downstream of the peak increased by approximately 150 percent.

Arimilli, R. V.; Keshock, E. G.; Smith, M. E.

1984-01-01

166

Thermal parameters determination of battery cells by local heat flux measurements  

NASA Astrophysics Data System (ADS)

A new approach to define of the thermal parameters, such as heat capacity and through-plane thermal conductivity, of pouch-type cells is introduced. Application of local heat flux measurement with a gradient heat flux sensor (GHFS) allows determination of the cell thermal parameters in different surface points of the cell. The suggested method is not cell destructive as it does not require deep discharge of the cell or application of any charge/discharge cycles during the measurements of the thermal parameters of the cell. The complete procedure is demonstrated on a high-power lithium-ion (Li-ion) pouch cell, and it is verified on a sample with well-known thermal parameters. A comparison of the experimental results with conventional thermal characterization methods shows an acceptably low error. The dependence of the cell thermal parameters on the state of charge (SoC) and measurement points on the surface was studied by the proposed measurement approach.

Murashko, K. A.; Mityakov, A. V.; Pyrhönen, J.; Mityakov, V. Y.; Sapozhnikov, S. S.

2014-12-01

167

Local stress and heat flux in atomistic systems involving three-body forces.  

PubMed

Local densities of fundamental physical quantities, including stress and heat flux fields, are formulated for atomistic systems involving three-body forces. The obtained formulas are calculable within an atomistic simulation, in consistent with the conservation equations of thermodynamics of continuum, and can be applied to systems with general two- and three-body interaction forces. It is hoped that this work may correct some misuse of inappropriate formulas of stress and heat flux in the literature, may clarify the definition of site energy of many-body potentials, and may serve as an analytical link between an atomistic model and a continuum theory. Physical meanings of the obtained formulas, their relation with virial theorem and heat theorem, and the applicability are discussed. PMID:16468857

Chen, Youping

2006-02-01

168

Incentives for co-firing in bio-fuelled industrial steam, heat and power production—Swedish experiences  

Microsoft Academic Search

Various combinations of co-firing of biofuels and fossil fuels can be used as an efficient method to rapidly introduce biofuels into existing energy systems. They also offer effective utilisation of local, small fuel resources, used mainly by larger plants. This study analyses different factors and incentives that influence co-firing in bio-fuelled industrial production of steam, heat and power and case

B Hillring

2003-01-01

169

Local melting and shape controlling of solder joint via induction heating  

Microsoft Academic Search

A rapid yet simple methodology to form the solder joints used in electronic packaging has been demonstrated through an induction heating system in this paper. The objective is to control the shapes of the solder joints precisely and form the hourglass-shaped solder joint using local melting phenomenon. For Sn–Ag eutectic solder bullet-shaped solder bumps and hourglass-shaped solder joints can be

Hongbo Xu; Mingyu Li; Jongmyung Kim; Daewon Kim

2009-01-01

170

Light-induced local heating for thermophoretic manipulation of DNA in polymer micro- and nanochannels.  

PubMed

We present a method for making polymer chips with a narrow-band near-infrared absorber layer that enables light-induced local heating of liquids inside fluidic micro- and nanochannels fabricated by thermal imprint in polymethyl methacrylate. We have characterized the resulting liquid temperature profiles in microchannels using the temperature dependent fluorescence of the complex [Ru(bpy)(3)](2+). We demonstrate thermophoretic manipulation of individual YOYO-1 stained T4 DNA molecules inside micro- and nanochannels. PMID:20166745

Thamdrup, Lasse H; Larsen, Niels B; Kristensen, Anders

2010-03-10

171

Local Measurement of Non-Classical Ion Heating During Magnetic Reconnection  

SciTech Connect

Local ion temperature is measured directly in the well-characterized reconnection layer of a laboratory plasma. These measurements demonstrate definitively that ions are heated due to reconnection and that more than half of the reconnected field energy is converted to ion kinetic energy. Neither classical Ohmic dissipation nor thermalization of energetic flows is sufficient to account for the energy converted, suggesting the importance of non-classical dissipation mechanisms such as wave-particle interactions.

G. Fiskel; H. Ji; M. Yamada; R.M. Kulsrud; S.C. Hsu; T.A. Carter

1999-11-01

172

Modeling thermochemical heat storage in porous media with local thermal nonequilibrium - From constitutive theory to application  

NASA Astrophysics Data System (ADS)

Heat processes in industry and for power generation can be made more cost-efficient and climate friendly by the integration of thermal energy storage devices. Due to high storage densities and superior long term storage characteristics, systems relying on thermochemical reactions are of great interest and often based on porous or granular media. As such, they share characteristic features in terms of mass and heat transport that are strongly coupled by physical and chemical phenomena. We have employed the theory of porous media to establish a model featuring reactive multicomponent compressible fluid mass transport through solid particle bed coupled to local thermal nonequilibrium heat transport. The model development has been based on an extensive evaluation of the Clausius-Duhem inequality to derive thermodynamically consistent constitutive relations for secondary variables as well as direct and indirect coupling terms. The model has then been implemented into the open source scientific simulation code OpenGeoSys using the finite element method. Lab and pilot scale thermochemical heat storage reactors with different reaction systems (oxidation reactions, hydration reactions) have been simulated successfully using axisymmetric geometries. The simulations show the strong coupling of pressure, concentration and temperature fields as well as the gas-solid reactions occurring inside the reactors. The effect of certain process parameters, such as mass flow and particle size, on the occurrence of local thermal nonequilibrium is illustrated. It is shown that the reactors can be used in a number of operating modes such as the extraction or release of heat accompanied by significant temperature drops or raises; the buffering or smoothing of temperature fluctuations at the inlet; the up- or downgrading of heat. The developed model therefore represents a useful tool to understand reactor behavior, optimize operating parameters, estimate thermal and parasitic losses, and dimension reactors depending on a specific application. Reaction rate during discharge of a thermochemical reactor. Red indicates areas with a high reaction rate, blue inactive regions.

Nagel, T.; Shao, H.; Linder, M.; Wörner, A.; Kolditz, O.

2013-12-01

173

Transient fluid flow and heat transfer in petroleum production systems  

NASA Astrophysics Data System (ADS)

Heat transfer is an important phenomenon in both wellbore and reservoir. The pertinent temperature distribution can provide a valuable perspective in analyzing and optimizing the oil production. In this work, two kinds of co-production, production fluid through the annulus and tubing, and through two independent tubings, have been modeled using steady state analysis. The fluid temperatures in the production string and annulus have been solved analytically in both cases. Furthermore, we extended the theory of steady state energy transport to remedy asphaltene deposition problem by circulating the cooling fluid in the annulus. Due to the complex nature of two-phase flow in the oil/gas production, more reliable mechanistic modeling approaches have been developed since early 1980's. Rooted in Hasan-Kabir model, we have developed a wellbore/reservoir coupling simulator for the transient non-Darcy two-phase flow in the flow-after-flow well test. The entire historical flow behavior has been modeled using superposition method and validated with field data. Our second simulation is for the investigation of a blowout well, which is a great concern in the oil field. When the pressure in the wellbore is sufficiently high, the fluids will attain sonic velocity at the wellhead. We presented a computational algorithm to estimate the blowout rate in a given wellbore/reservoir system and examined four major parameters, such as formation permeability, Gas-Oil-Ratio (GOR), reservoir pressure and tubing diameter. The transient nature of this approach also illustrates the evolution process of a blowout. We have also developed a transient simulator to determine the location and severity of a blockage in a gas pipeline based on the theory of two-phase flow and pressure transient analysis. The presence of a sizeable blockage will affect the outlet gas pressure response by decreasing the available pipe volume and increasing the friction loss of the fluid flow. The simulator solves for the pressure response using a finite and iterative numerical method with transport theory of mass and momentum. Comparing the outlet transient pressure signature from a clean pipeline with those having a plug shows that the predictions of our model agree well with the experimental data.

Lin, Dongqing

174

The global potential of local peri-urban food production  

NASA Astrophysics Data System (ADS)

One big challenge for the rest of the 21st century will be the massive urbanisation. It is expected that more than 7 out of 10 persons will live in a city by the year 2050. Crucial developments towards a sustainable future will therefore take place in cities. One important approach for a sustainable city development is to re-localize food production and to close urban nutrient cycles through better waste management. The re-location of food production avoids CO2 emissions from transportation of food to cities and can also generate income for inhabitants. Cities are by definition locations where fertility accumulates. As cities are often built along rivers, their soils are often fertile. Furthermore, labour force and the possibility of producing fertilizer from human fecal matter within the city promises sustainable nutrients cycles. Although urban and peri-urban agriculture can be found in many cities worldwide and already have a substantial contribution to food supply, it has not jet been comprehensibly structured by research. We combine several worldwide data sets to determine the supply of cities with regional food production, where regional is defined as a production that occurs very close to the consumption within the peri-urban area. Therefore, urban areas are not defined by administrative boundaries but by connected built-up urban areas, and peri-urban area by the surrounding area with the same size multiplied with a scaling parameter. Both together accumulate to an urban-bio-region (UBR). With regard to national food consumption, a linear program achieves the best possible yield on agricultural areas and allows the computation of the fraction of population, which can be nourished. Additionally, several climate scenarios and different dietary patterns were considered. To close the gap between single case studies and to provide a quantitative overview of the global potential of peri-urban food production we used high resolution land-use data Global Land Cover Service (GlobCover), the global agricultural yield dataset from the Global Agro-ecological Zones (GAEZ) and census population data from the Global Rural-Urban Mapping Project, Version 1 (GRUMPv1) to estimate the potential of 2838 UBR worldwide. With regard to making use of local circumstances, the results of potential worldwide peri-urban agriculture emphasize the ongoing investigation of sustainable transitions of the socio-ecologic system. Identifying areas for increased food production while maintaining the natural resources and the urban needs will be a major task for cities in future.

Kriewald, Steffen; Garcia Cantu Ros, Anselmo; Sterzel, Till; Kropp, Jürgen P.

2013-04-01

175

Differential heat shock tolerance and expression of heat shock inducible proteins in two stored-product psocids  

Technology Transfer Automated Retrieval System (TEKTRAN)

The recent recognition of psocid infestations as a major concern in stored products, where their management with fumigants and conventional insecticides has proven difficult, and also the recent reemergence of heat treatment as a potential tactic for control of stored-product insects led to the pres...

176

Characteristic of local boiling heat transfer of ammonia and ammonia / water binary mixture on the plate type evaporator  

NASA Astrophysics Data System (ADS)

Power generation using small temperature difference such as ocean thermal energy conversion (OTEC) and discharged thermal energy conversion (DTEC) is expected to be the countermeasures against global warming problem. As ammonia and ammonia/water are used in evaporators for OTEC and DTEC as working fluids, the research of their local boiling heat transfer is important for improvement of the power generation efficiency. Measurements of local boiling heat transfer coefficients were performed for ammonia /water mixture ( z = 0.9-1) on a vertical flat plate heat exchanger in a range of mass flux (7.5-15 kg/m2 s), heat flux (15-23 kW/m2), and pressure (0.7-0.9 MPa). The result shows that in the case of ammonia /water mixture, the local heat transfer coefficients increase with an increase of mass flux and composition of ammonia, and decrease with an increase of heat flux.

Okamoto, Akio; Arima, Hirofumi; Ikegami, Yasuyuki

2011-08-01

177

An experimental study of local and mean heat transfer in a triangular-sectioned duct rotating in the orthogonal mode  

NASA Astrophysics Data System (ADS)

This paper presents a selection of experimental results that examines the influence of orthogonal-mode rotation on local and mean heat transfer in a triangular-sectioned duct with potential application to cooled turbine rotor blades. It is shown that Coriolis acceleration can have a beneficial influence on mean heat transfer relative to the nonrotating case at the lower range of turbulent pipe flow Reynolds numbers studied. Also, rotational buoyancy has been shown to have a noticeable effect over this same Reynolds number range in that progressively increasing buoyancy brings about an attendant reduction in heat transfer. As the Reynolds numbers are increased, say, beyond 30,000, buoyancy effects were found to have little influence on mean heat transfer over the speed range covered. Local axial variations in heat transfer along the duct were also measured, and severe reductions in local heat transfer were detected under certain operating circumstances.

Clifford, R. J.; Morris, W. D.; Harasgama, S. P.

1984-07-01

178

Local Heat Transfer and CHF for Subcooled Flow Boiling - Annual Report 1996  

SciTech Connect

For the past decade, efforts have been growing in the development of high heat flux (HHF) components for many applications, including fusion and fission reactor components, advanced electronic components, synchrotrons and optical components, and other advanced HHF engineering applications. From a thermal prospective, work in the fusion reactor development arena has been underway in a number of areas including: (1) Plasma thermal, and electro-magnetics, and particle transport, (2) Fusion material, rheology, development, and expansion and selection; (3) High heat flux removal; and (4) Energy production and efficiency.

Dr. Ronald D. Boyd

2000-07-01

179

Rupture of a Locally Heated Liquid Film Driven by the Shear Stress of Gas and Gravity  

NASA Astrophysics Data System (ADS)

The paper focuses on the recent progress that has been achieved by the authors through conducting experiments with locally heated shear-driven and falling liquid films. Rupture of the liquid film was investigated and it was found that scenario of film rupture differs widely for different flow regimes. The critical heat flux is about 10 times higher for a shear driven film than that for a falling liquid film, and reaches 250 W/cm2 in experiments with water at atmospheric pressure. Rupture of a subcooled falling liquid film heated from the substrate is preceded by the formation of steady state film surface deformations. The film spontaneously ruptures at the moment when the film thickness in the thinned region reaches a certain critical minimum independent of both the Reynolds number and the plate inclination angle (gravity force). By means of high speed imaging it is found that the process of rupture involves two stages: 1) abrupt film thinning down to a thin residual film; 2) rupture and dryout of the residual film. As the plate inclination angle is reduced the threshold heat flux required for film rupture weakly decreases, however when the angle becomes negative the threshold heat flux begins to rise dramatically, which is associated with an increase of the stabilizing hydrostatic effect due to the growth of the film thickness.

Zaitsev, D. V.; Kabob, O. A.

2010-03-01

180

Local Heating of Discrete Droplets Using Magnetic Porous Silicon-Based Photonic Crystals  

PubMed Central

This paper describes a method for local heating of discrete micro-liter scale liquid droplets. The droplets are covered with magnetic porous Si microparticles, and heating is achieved by application of an external alternating electromagnetic field. The magnetic porous Si microparticles consist of two layers: the top layer contains a photonic code and it is hydrophobic, with surface-grafted dodecyl moieties. The bottom layer consists of a hydrophilic Si oxide host layer that is infused with Fe3O4 nanoparticles. The amphiphilic microparticles spontaneously align at the interface of a water droplet immersed in mineral oil, allowing manipulation of the droplets by application of a magnetic field. Application of an oscillating magnetic field (338 kHz, 18A RMS current in a coil surrounding the experiment) generates heat in the superparamagnetic particles that can raise the temperature of the enclosed water droplet to >80 °C within 5 min. A simple microfluidics application is demonstrated: combining complementary DNA strands contained in separate droplets and then thermally inducing dehybridization of the conjugate. The complementary oligonucleotides were conjugated with the cyanine dye fluorophores Cy3 and Cy5 to quantify the melting/re-binding reaction by fluorescence resonance energy transfer (FRET). The magnetic porous Si microparticles were prepared as photonic crystals, containing spectral codes that allowed the identification of the droplets by reflectivity spectroscopy. The technique demonstrates the feasibility of tagging, manipulating, and heating small volumes of liquids without the use of conventional microfluidic channel and heating systems. PMID:16771508

Park, Ji-Ho; Derfus, Austin M.; Segal, Ester; Vecchio, Kenneth S.; Bhatia, Sangeeta N.; Sailor, Michael J.

2012-01-01

181

Natural convection in horizontal porous layers with localized heating from below  

SciTech Connect

Convective flow of fluid through saturated porous media heated from below is of considerable interest, and has been extensively studied. Most of these studies are concerned with either infinite horizontal porous layers or rectangular (or cylindrical) porous cavities with adiabatic vertical walls. A related problem of practical importance occurs when only a portion of the bottom surface is heated and the rest of it is either adiabatic or isothermally cooled. This situation is encountered in several geothermal areas which consists of troughs of volcanic debris contained by walls of nonfragmented ignimbrite. Thus, the model region considered is a locally heated long trough of isotropic porous medium confined by impermeable and insulating surroundings. Also, the recent motivation to study this problem has come from the efforts to identify a geologic repository for nuclear waste disposal. The purpose of the present work is to consider the effects of aspect ratio and Rayleigh number on free convection heat transfer from an isothermal heat source centrally located on the bottom surface of a horizontal porous cavity.

Prasad, V. (Columbia Univ., New York, NY (United States)); Kulacki, F.A. (Univ. of Delaware, Newark (United States))

1987-08-01

182

SIGNATURES OF IMPULSIVE LOCALIZED HEATING IN THE TEMPERATURE DISTRIBUTION OF MULTI-STRANDED CORONAL LOOPS  

SciTech Connect

We study the signatures of coronal heating on the differential emission measure (DEM) by means of hydrodynamic simulations capable of resolving the chromospheric-corona transition region sections of multi-stranded coronal loops and following their evolution. We consider heating either uniformly distributed along the loop or localized close to the chromospheric footpoints, in both steady and impulsive regimes. Our simulations show that condensation at the top of the loop forms when the impulsive heating, with a pulse cadence lower than the plasma cooling time, is localized at the loop footpoints, and the pulse energy is below a threshold above which the heating balances the radiative losses, thus preventing the catastrophic cooling which triggers the condensation. A condensation does not produce observable signatures in the DEM because it does not redistribute the plasma over a sufficiently large temperature range. On the other hand, the DEM coronal peak is found sensitive to the pulse cadence time when this is longer or comparable to the plasma cooling time. In this case, the heating pulses produce large oscillations in temperature in the bulk of the coronal plasma, which effectively smears out the coronal DEM structure. The pronounced DEM peak observed in active regions would indicate a predominance of conditions in which the cadence time is shorter or of the order of the plasma cooling time, whilst the structure of the quiet-Sun DEM suggests a cadence time longer than the plasma cooling time. Our simulations give an explanation of the warm overdense and hot underdense loops observed by TRACE, SOHO, and Yohkoh. However, they are unable to reproduce both the transition region and the coronal DEM structure with a unique set of parameters, which outlines the need for a more realistic description of the transition region.

Susino, R.; Lanzafame, A. C. [Dipartimento di Fisica e Astronomia - Sezione Astrofisica, Universita di Catania, via S. Sofia 78, I-95123 Catania (Italy); Lanza, A. F.; Spadaro, D. [INAF-Osservatorio Astrofisico di Catania, via S. Sofia 78, I-95123 Catania (Italy)

2010-01-20

183

RELATIONSHIP BETWEEN AGING AND NUTRITIONAL CONTROLLED GROWTH RATE ON HEAT PRODUCTION OF EWE LAMBS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The objective of this study was to determine how reducing growth rate nutritionally alters the relationship between heat production per unit body weight and aging. Fasting heat production of 12 Dorset ewe lambs at 114 ± 2 d of age was determined, and ewes were assigned to treatments. Treatments co...

184

Respiration and heat production by the inflorescence of Philodendron selloum Koch  

Microsoft Academic Search

During a 2-d sequence of anthesis, the spadices of the thermogenic arum lily, Philodendron selloum, regulated maximum temperature within a small range (37–44°C) by reversible thermal inhibition of respiratory heat production. This response protects the inflorescence and the attracted insects from thermal damage. Heat production by whole spadices, measured by O2 respirometry, equalled heat loss, measured by gradient layer calorimetry,

Roger S. Seymour; George A. Bartholomew; M. Christopher Barnhart

1983-01-01

185

Effect of gage size on the measurement of local heat flux. [formulas for determining gage averaging errors  

NASA Technical Reports Server (NTRS)

General formulas are derived for determining gage averaging errors of strip-type heat flux meters used in the measurement of one-dimensional heat flux distributions. In addition, a correction procedure is presented which allows a better estimate for the true value of the local heat flux. As an example of the technique, the formulas are applied to the cases of heat transfer to air slot jets impinging on flat and concave surfaces. It is shown that for many practical problems, the use of very small heat flux gages is often unnecessary.

Baumeister, K. J.; Papell, S. S.

1973-01-01

186

Localization of RNA from Heat-Induced Polysomes at Puff Sites in Drosophila melanogaster Susan Lindquist McKenzie, Steven Henikoff, and Matthew Meselson  

E-print Network

Localization of RNA from Heat-Induced Polysomes at Puff Sites in Drosophila melanogaster Susan Localization of RNA from Heat-Induced Polysomes at Puff Sites in Drosophila melanogaster (chromosome puffs. Like the heat shock puffs on polytene chromosomes which appear while preexisting puffs regress, heat

Lindquist, Susan

187

Spectral non-uniform temperature and non-local heat transfer in the spin Seebeck effect  

NASA Astrophysics Data System (ADS)

Recently discovered spin-dependent thermoelectric effects have merged spin, charge, and thermal physics, known as spin caloritronics, of which the spin Seebeck effect is its most puzzling. Here we present a theory of this effect driven by subthermal non-local phonon heat transfer and spectral non-uniform temperature. The theory explains its non-local behaviour from the fact that phonons that store the energy (thermal) and the phonons that transfer it (subthermal) are located in different parts of the spectrum and have different kinetics. This gives rise to a spectral phonon distribution that deviates from local equilibrium along the substrate and is sensitive to boundary conditions. The theory also predicts a non-magnon origin of the effect in ferromagnetic metals in agreement with observations in recent experiments. Equilibration of the heat flow from the substrate to the Pt probe and backwards leads to a vertical spin current produced by the spin-polarized electrons dragged by the thermal phonons.

Tikhonov, Konstantin S.; Sinova, Jairo; Finkel'Stein, Alexander M.

2013-06-01

188

Models relevant to excess heat production in fleischmann-pons experiments  

E-print Network

Observations of excess heat in the absence of commensurate energetic charged particles challenges local energy and momentum conservation, a foundation of nuclear physics. We have explored models based on excitation transfer, ...

Hagelstein, Peter L.

189

The role of radiation transport in the thermal response of semitransparent materials to localized laser heating  

NASA Astrophysics Data System (ADS)

Lasers are widely used to modify the internal structure of semitransparent materials for a wide variety of applications, including waveguide fabrication and laser glass damage healing. The gray diffusion approximation used in past models to describe radiation cooling is not adequate for these materials, particularly near the heated surface layer. In this paper we describe a computational model based upon solving the radiation transport equation in 1D by the Pn method with ˜500 photon energy bands, and by multi-group radiation diffusion in 2D with fourteen photon energy bands. The model accounts for the temperature-dependent absorption of infrared laser light and subsequent redistribution of the deposited heat by both radiation and conductive transport. We present representative results for fused silica irradiated with 2-12 W of 4.6 or 10.6 µm laser light for 5-10 s pulse durations in a 1 mm spot, which is small compared to the diameter and thickness of the silica slab. We show that, unlike the case for bulk heating, in localized infrared laser heating radiation transport plays only a very small role in the thermal response of silica.

Colvin, Jeffrey; Shestakov, Aleksei; Stölken, James; Vignes, Ryan

2011-03-01

190

The role of radiation transport in the thermal response of semitransparent materials to localized laser heating  

SciTech Connect

Lasers are widely used to modify the internal structure of semitransparent materials for a wide variety of applications, including waveguide fabrication and laser glass damage healing. The gray diffusion approximation used in past models to describe radiation cooling is not adequate for these materials, particularly near the heated surface layer. In this paper we describe a computational model based upon solving the radiation transport equation in 1D by the P{sub n} method with {approx}500 photon energy bands, and by multi-group radiation diffusion in 2D with fourteen photon energy bands. The model accounts for the temperature-dependent absorption of infrared laser light and subsequent redistribution of the deposited heat by both radiation and conductive transport. We present representative results for fused silica irradiated with 2-12 W of 4.6 or 10.6 {mu}m laser light for 5-10 s pulse durations in a 1 mm spot, which is small compared to the diameter and thickness of the silica slab. We show that, unlike the case for bulk heating, in localized infrared laser heating radiation transport plays only a very small role in the thermal response of silica.

Colvin, Jeffrey; Shestakov, Aleksei; Stoelken, James; Vignes, Ryan [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551 (United States)

2011-03-01

191

Thermal convection with large viscosity variation in an enclosure with localized heating  

SciTech Connect

The present study is undertaken in order to gain an understanding of convective transport in a magma chamber. We have chosen to represent the chamber by an enclosure with localized heating from below. Results of both laboratory experiments and computer modeling are reported. The experimental apparatus consists of a transparent enclosure with a square planform. An electrically heated strip, with a width equal to one-fourth of the length of a side of the enclosure, is centered on the lower inside surface of the enclosure. For the experiments reported here, the top of the fluid layer is maintained at a constant temperature and the depth of the layer is equal to the width of the heated strip. The large viscosity variation characteristic of magma convection is simulated by using corn syrup as the working fluid. Measured velocity and temperature distribution as well as overall heat transfer rates are presented. The experiment is numerically simulated through use of a finite element computer program. Numerically predicted streamlines, isotherms, and velocity distributions are presented for the transverse vertical midplane of the enclosure. Good agreement is demonstrated between predictions and measurements. 23 refs., 8 figs., 2 tabs.

Chu, T.Y.; Hickox, C.E.

1988-01-01

192

Summary. Heat-shielding is a method used by honey bee workers to insulate temperature sensitive brood from localized  

E-print Network

localized temperature stressors. Key words: Apis mellifera, thermoregulation, heat-shielding. Introduction that serve to maintain constant hive temperature. To decrease tem- perature, bees fan wings and spread water

Starks, Philip

193

Low-temperature heat capacity and localized vibrational modes in natural and synthetic tetrahedrites  

SciTech Connect

The heat capacity of natural (Cu{sub 12?x} (Fe, Zn, Ag){sub x}(Sb, As){sub 4}S{sub 13}) and synthetic (Cu{sub 12?x}Zn{sub x}Sb{sub 4}S{sub 13} with x?=?0, 1, 2) tetrahedrite compounds was measured between 2?K and 380?K. It was found that the temperature dependence of the heat capacity can be described using a Debye term and three Einstein oscillators with characteristic temperatures that correspond to energies of ?1.0?meV, ?2.8?meV, and ?8.4?meV. The existence of localized vibrational modes, which are assigned to the displacements of the trigonally coordinated Cu atoms in the structure, is discussed in the context of anharmonicity and its effect on the low lattice thermal conductivity exhibited by these compounds.

Lara-Curzio, E., E-mail: laracurzioe@ornl.gov; May, A. F.; Delaire, O.; McGuire, M. A. [Materials Science and Technology Division, Oak Ridge National Laboratory, 1 Bethel Valley Rd., Oak Ridge, Tennessee 37831 (United States); Lu, X.; Liu, Cheng-Yun; Case, E. D.; Morelli, D. T. [Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824 (United States)

2014-05-21

194

Wave transmission, phonon localization and heat conduction of 1D Frenkel-Kontorova chain  

E-print Network

We study the transmission coefficient of a plane wave through a 1D finite quasi-periodic system -- the Frenkel-Kontorova (FK) model -- embedding in an infinite uniform harmonic chain. By varying the mass of atoms in the infinite uniform chain, we obtain the transmission coefficients for {\\it all} eigenfrequencies. The phonon localization of the incommensurated FK chain is also studied in terms of the transmission coefficients and the Thouless exponents. Moreover, the heat conduction of Rubin-Greer-like model for FK chain at low temperature is calculated. It is found that the stationary heat flux $J(N)\\sim N^{\\alpha}$, and $\\alpha$ depends on the strength of the external potential.

Peiqing Tong; Baowen Li; Bambi Hu

1999-01-20

195

The effect of intermittent local heat and cold on labor pain and child birth outcome  

PubMed Central

Background: Labor pain is one of the severest pains that cause many women request cesarean section for fear of pain. Thus, controlling labor pain is a major concern of maternity care. Nowadays, interest in non-pharmacological pain relief methods has been increased because of their lower side effects. The effects of discrete heat and cold on decreasing labor pain have been reported but there was no evaluation of the effects of simultaneous heat and cold. The aim of this study was to investigate the effect of intermittent heat and cold on pain severity and childbirth outcomes. Materials and Methods: This study was a randomized controlled trial. Sixty-four nulliparous women with term, One fetus, and low-risk pregnancy were divided into the intervention (32 participants) and the control group (32 participants) by random allocation. Excluding criteria were: administration of pain relief drugs, skin disease in the field of intervention, fetal distress, bleeding, fever, and disagreement with participation in the study. Warm and cold packs were used intermittently on low back and lower abdomen during the first phase and on perineum during the second phase of labor. Pain intensity was assessed with Visual Analogue Scale. Descriptive statistic, chi square, and t-test were used for data analysis. Results: There were no significant differences in demographic and midwifery characteristics and the baseline pain between two groups. The pain was significantly lower in intervention group during the first and second phases of labor. Duration of the first and third phases of labor was shorter in the case group. There were no significant differences in type of delivery, perineal laceration, oxytocin uptake, fetal heart rate, and APGAR between two groups. Discussion: Local warming with intermittent cold pack can reduce labor pain without adverse effects on maternal and fetal outcomes. It is an inexpensive and simple method. Conclusion: Intermittent local heat and cold therapy is a no pharmalogical, safe and effective method to relief labor pain. PMID:24403926

Ganji, Zhila; Shirvani, Marjan A.; Rezaei-Abhari, Farideh; Danesh, Mahmonir

2013-01-01

196

Heat conductivity from molecular chaos hypothesis in locally confined billiard systems.  

PubMed

We study the transport properties of a large class of locally confined Hamiltonian systems, in which neighboring particles interact through hard-core elastic collisions. When these collisions become rare and the systems large, we derive a Boltzmann-like equation for the evolution of the probability densities. We solve this equation in the linear regime and compute the heat conductivity from a Green-Kubo formula. The validity of our approach is demonstrated by comparing our predictions with the results of numerical simulations performed on a new class of high-dimensional defocusing chaotic billiards. PMID:19113325

Gilbert, Thomas; Lefevere, Raphaël

2008-11-14

197

Well-posedness and spectral properties of heat and wave equations with non-local conditions  

E-print Network

We consider the one-dimensional heat and wave equations but -- instead of boundary conditions-- we impose on the solution certain non-local, integral constraints. An appropriate Hilbert setting leads to an integration-by-parts formula in Sobolev spaces of negative order and eventually allows us to use semigroup theory leading to analytic well-posedness, hence sharpening regularity results previously obtained by other authors. In doing so we introduce a parametrization of such integral conditions that includes known cases but also shows the connection with more usual boundary conditions, like periodic ones. In the self-adjoint case, we even obtain eigenvalue asymptotics of so-called Weyl's type.

Delio Mugnolo; Serge Nicaise

2014-01-03

198

Treatment of material discontinuity in two meshless local Petrov-Galerkin (MLPG) formulations of axisymmetric transient heat conduction  

Microsoft Academic Search

SUMMARY We use two meshless local Petrov-Galerkin (MLPG) formulations to analyse heat conduction in a bimetallic circular disk. The continuity of the normal component of the heat flux at the interface between two materials is satisfied either by the method of Lagrange multipliers or by using a jump function. The convergence of the H 0 and H 1 error norms

R. C. Batra; M. Porfiri; D. Spinello

2004-01-01

199

Determination of the local heat-transfer characteristics on glaze ice accretions on a cylinder and a NACA 0012 airfoil  

Microsoft Academic Search

Laboratory scale experiments conducted in the subsonic wind tunnel facility at the University of Kentucky are discussed. Experimental convective local heat transfer coefficients were obtained for a simulated, full scale, selected set of 2, 5, 15 minute glaze ice models on a cylinder, and 0, 5 minute glaze ice models on a NACA 0012 airfoil. A steady state heat flux

Martin Rabindra Pais

1987-01-01

200

Analytical determination of local surface heat-transfer coefficients for cooled turbine blades from measured metal temperatures  

NASA Technical Reports Server (NTRS)

Analytical methods are presented for the determination of local values of outside and inside heat-transfer coefficients and effective gas temperatures by use of turbine-blade-temperature measurements. The methods are derived for a number of configurations that can be applied to typical cooled-turbine-blade shapes as well as to other types of heat-transfer apparatus.

Brown, W Byron; Esgar, Jack B

1950-01-01

201

Boiling heat transfer in a vertical microchannel: Local estimation during flow boiling with a non intrusive method  

E-print Network

Boiling heat transfer in a vertical microchannel: Local estimation during flow boiling with a non the results of experimental and numerical studies concerning boiling heat transfer inside vertical of boiling flows in microscale's geometry, it is vital to quantify these transfers. To achieve this goal

202

Effect of Heating Treatments, Processing Methods and Refrigerated Storage of Milk and Some Dairy Products on Lipids Oxidation  

E-print Network

Abstract: The effect of heating treatments (pasteurization and boiling), micro waving, processing steps and storage of milk and some locally produced dairy products (Brined white cheese (Nabulsi), Yogurt and Labaneh on chemical changes of milk lipids were evaluated. The Peroxide value (POV) p-anisidine value (p-AV), thiobarbituric acid (TBA), free fatty acid and totox were determined. The heating treatments of milk do significantly increase the levels of the oxidation parameters such as POV compared to those of fresh raw milk. The highest POV value (mEq O 2/kg fat) was for milk pasteurized at 95±1.0°C for 15 min (0.435), followed by milk heated at 63±1.0°C for 30 min (0.381), whereas, the lowest value was for milk pasteurized at 85±1.0°C for 16 sec (0.234). Key words: Fat oxidation, peroxide value, ultra-high temperature, thiobarbituric acid, D-anisidine value,

Meshref A. Al-rowaily

203

Effects of polypropylene and polytetrafluoroethylene prostheses for abdominal plasty on local and systemic cytokine production.  

PubMed

We studied the effects of Esphyl polypropylene mesh and Ecoflon polytetrafluoroethylene endoprostheses on local and systemic production of cytokines. Polytetrafluoroethylene is a more reactogenic material than polypropylene; it stimulates mainly the local production of pro-inflammatory cytokines. The local anti-inflammatory effect of polypropylene was less pronounced, but persisted for longer time. PMID:24771444

Grigoryuk, A A; Turmova, E P

2014-02-01

204

New industrial heat pump applications to fructose production  

SciTech Connect

An energy cost reduction study of the American Fructose Decatur,Inc. High Fructose Corn Syrup process has been completed. The objective was to find cost effective energy cost reduction projects and to develop a coherent strategy for realizing the savings. There are many possible options for reducing energy cost. To facilitate a fair comparison of the options, Pinch Technology was used to identify appropriate heat recovery, heat pumping and cogeneration options. Of particular interest were the opportunities for utilizing heat pumps, for energy cost reduction or other profit increasing uses. Therefore, where a heat pumping scheme was identified, its merits relative to other potential projects was carefully evaluated to ensure that the heat pump was technically and economically sound. It is felt that the results obtained in this study are applicable to other wet corn milling sites which include a refinery section, due to the similarity of processes throughout the industry. This study and others indicate that reductions in thermal energy consumption of 15--25% can be expected through increased heat recovery. Also, the use of MVR and thermocompression evaporators is appropriate and additional economically viable opportunities exist for using industrial heat pumps to increase even further the level of energy cost reduction achievable. 17 figs., 4 tabs.

Not Available

1990-04-01

205

New industrial heat pump applications to textile production  

SciTech Connect

Application of pinch technology to the US industries in an early screening study has identified potential for heat pumps in several standard processes such as distillation and drying processes. Due to lack process information, the previous study was not able to draw any definite conclusion concerning the heat pump application potential in textile process. However, the commonly encountered drying process in the finishing section of textile plant has been shown to create opportunities for heat pump placement. The site selected for this study is a textile plant in North Carolina and the participating utility is Duke Power Company. The objective of this study is to further identify the energy savings potential through advanced heat pumps and other energy conservation methods developed in the context of pinch technology. The key findings of this study are as follows. The previously unrecoverable waste heat from the exhaust air can now be reclaimed through a spray type air washer and heat pump system. The recommended heat pump system recovers heat from the looper exhaust and use it to preheat the air in the gas tenter. A reduction of 50% of the gas consumption in the tenter can be achieved. The removal of lint from the exhaust air reduced the potential of air pollution. The collected lint can be burned in the boiler as a supplemental fuel source to reduce the fuel consumption in the plant. With fuel price predicted to go up and electricity price remain relatively stable in the future, the heat pump system can payback in less than three years. 15 figs., 4 tabs.

none,

1990-12-01

206

DOES THE LOCAL EMBEDDEDNESS OF ENERGY PRODUCTION CONTRIBUTE TO SUSTAINABLE RURAL DEVELOPMENT? SOME  

E-print Network

1 DOES THE LOCAL EMBEDDEDNESS OF ENERGY PRODUCTION CONTRIBUTE TO SUSTAINABLE RURAL DEVELOPMENT wind energy is materialised at local level it seems important also to think locally its development. It proposes several ways to include the local society in the wind energy development. Résumé : Parce que l

Boyer, Edmond

207

Fine-tuning of the transmission characteristics of an arc-induced long-period fiber grating by local heating  

NASA Astrophysics Data System (ADS)

A method for tuning the transmission characteristics of arc-induced long-period fiber gratings by local heating is presented. A traveling burner, produced by the combustion of a mixture of oxygen and butane, locally heats the longperiod grating producing a wavelength shift of the resonant peaks. We have found that the resonant wavelengths are blue-shifted during the first 7 round trips of the flame, but when heating process continues the notches shifts toward longer wavelengths. A fine and long range tuning of the resonant wavelengths up to 120 nm can be achieved without substantial degradation on the grating characteristics. The process is repeatable and only takes a few minutes.

Monzón-Hernandez, D.; Torres-Gómez, I.; Martínez-Ríos, A.; Salas-Alcántara, K.

2009-10-01

208

Local convective heat transfer for laminar and turbulent flow in a rotor-stator system  

NASA Astrophysics Data System (ADS)

The aim of this work is to show a better comprehension of the flow structure and thermal transfer in a rotor-stator system with a central opening in the stator and without an airflow imposed. The experimental technique uses infrared thermography to measure the surface temperatures of the rotor and the numerical solution of the steady-state heat equation to determine the local heat transfer coefficients. Analysis of the flow structure between the rotor and the stator is conducted by PIV. Tests are carried out for rotational Reynolds numbers ranging from 5.87×104 to 1.4×106 and for gap ratios ranging from 0.01 to 0.17. Analysis of the experimental results has determined the influence of the rotational Reynolds number, the gap ratio and system’s geometry on the flow structure, and the convective exchanges in the gap between the rotor and the stator. Some correlations expressing the local Nusselt number as a function of the rotational Reynolds number and the gap ratio are proposed.

Boutarfa, Rachid; Harmand, Souad

2005-02-01

209

Heat stress induced ethylene production in developing wheat grains induces kernel abortion and increased maturation in a susceptible cultivar  

Microsoft Academic Search

In this work we present evidence that the heat stress induced kernel abortion and suppression of grain maturation in a representative heat susceptible hard red winter wheat (Triticum aestivum L.) cultivar is regulated by heat stress induced ethylene production. Exposure to heat stress (38°C) during early kernel development (10 DAP) resulted in a 6-fold increase in ethylene production in developing

Dirk B. Hays; Jung Hwa Do; Richard E. Mason; Gaylon Morgan; Scott A. Finlayson

2007-01-01

210

Local heating of human skin by millimeter waves: effect of blood flow.  

PubMed

We investigated the influence of blood perfusion on local heating of the forearm and middle finger skin following 42.25 GHz exposure with an open ended waveguide (WG) and with a YAV mm wave therapeutic device. Both sources had bell-shaped distributions of the incident power density (IPD) with peak intensities of 208 and 55 mW/cm(2), respectively. Blood perfusion was changed in two ways: by blood flow occlusion and by externally applied vasodilator (nonivamide/nicoboxil) cream to the skin. For thermal modeling, we used the bioheat transfer equation (BHTE) and the hybrid bioheat equation (HBHE) which combines the BHTE and the scalar effective thermal conductivity equation (ETCE). Under normal conditions with the 208 mW/cm(2) exposure, the cutaneous temperature elevation (DeltaT) in the finger (2.5 +/- 0.3 degrees C) having higher blood flow was notably smaller than the cutaneous DeltaT in the forearm (4.7 +/- 0.4 degrees C). However, heating of the forearm and finger skin with blood flow occluded was the same, indicating that the thermal conductivity of tissue in the absence of blood flow at both locations was also the same. The BHTE accurately predicted local hyperthermia in the forearm only at low blood flow. The HBHE made accurate predictions at both low and high perfusion rates. The relationship between blood flow and the effective thermal conductivity (k(eff)) was found to be linear. The heat dissipating effect of higher perfusion was mostly due to an apparent increase in k(eff). It was shown that mm wave exposure could result in steady state heating of tissue layers located much deeper than the penetration depth (0.56 mm). The surface DeltaT and heat penetration into tissue increased with enlarging the irradiating beam area and with increasing exposure duration. Thus, mm waves at sufficient intensities could thermally affect thermo-sensitive structures located in the skin and underlying tissue. PMID:15931684

Alekseev, S I; Radzievsky, A A; Szabo, I; Ziskin, M C

2005-09-01

211

Changes in heat production by mature cows after changes in feeding level.  

PubMed

We hypothesized that adaptation of heat production in the realimented cow would occur over an extended period, and the length of time would be influenced by the level of feed. Our objectives were to quantify the changes in heat production of cows after feed restriction and to quantify the effect of level of realimentation on the dynamics of heat production in lightweight cows. Forty 4-yr-old nonpregnant, nonlacting cows (4-breed composite: 1/4 Hereford, 1/4 Angus, 1/4 Red Poll, and 1/4 Pinzgauer) were randomly assigned to receive 1 of 4 levels of a common alfalfa hay source. All cows were feed-restricted [50.0 g of DM/metabolic body size (MBS, kg of BW(0.75)); period 1], and individual fed heat production measurements were taken 0, 7, 13, 28, 56, and 91 d after feed restriction (period 1). In period 2, cows were fed their assigned feed level for their treatment after d 91 of restriction: 50.0 (T50.0), 58.5 (T58.5), 67.0 (T67.0), and 75.5 (T75.5) g of DM/MBS. Measures were taken at 7, 13, 28, 42, 56, 91, 119, and 175 d. In period 3, all cows were fed 75.5 g of DM/MBS after their 175-d measurement, and measures were taken at 7, 14, 28, 56, and 112 d later. In period 1, heat production decreased rapidly during the first 7 d of feed restriction, and heat production continued to decrease during the 91-d restriction. Heat production increased rapidly within the first 7 d, but chronic adaptation continued for T75.5 and T67.0 cows. In period 3, heat production increased rapidly during the first 7 d. Heat production scaled for metabolic body size tended to differ among treatments (P = 0.11). Daily heat production increased by 2.5 kcal/d. These data suggest that there is not a lag in heat production during realimentation and that increased recovered energy is associated with a rapid increase in heat production. PMID:16699100

Freetly, H C; Nienaber, J A; Brown-Brandl, T

2006-06-01

212

Specific thermal responsiveness of ventromedial hypothalamic neurons to localized scrotal heating and cooling in rats.  

PubMed Central

1. The specificity of thermoresponsive ventromedial hypothalamic (VMH) neurons to localized, incremental scrotal thermal cooling and heating of urethane-anaesthetized male Sprague-Dawley rats (maintained at 37 degrees C colonically) was investigated. 2. Ventromedial hypothalamic extracellular neuronal activity and surface (scalp) electroencephalogram (EEG) activity from the parietal region were recorded. Intrascapular brown adipose tissue (TIBAT), surface tail (Tt) and scrotal (Tsc) temperatures, where thermal stimulation was evoked, were also monitored. 3. One hundred and twenty-five VMH neurons were recorded, with forty (32%) VMH neurons classified as warm-responsive neurons (WRNs), twenty-three (18%) as coldresponsive neurons (CRNs) and sixty-two (50%) as thermal non-responsive neurons (TNRNs) based on their thermal coefficients. Of VMH WRNs, 60% (i.e. 24) were classified as having biphasic neuronal activity responses, as were 60% (i.e. 14 of 23) of the CRNs. Forty per cent of WRNs and CRNs were classified as having monophasic changes in neuronal activity. 4. Scrotal heating or cooling from 5 to 40 degrees C resulted in specific firing rate changes of VMH WRNs and CRNs without any associated change in EEG activity (i.e. no significant change in EEG frequency or amplitude from initial baseline EEG activity when Tsc was 20 degrees C). EEG desynchronization (increased EEG frequency, decreased amplitude) was only observed when scrotal temperatures were at 45 degrees C or after each tail pinch (noxious stimulation) but not with scrotal brushing (mechanical stimulation). 5. With core temperature maintained at 37 degrees C, localized, scrotal heating and cooling of rats did not induce IBAT temperature changes indicative of brown adipose tissue activation, but delayed changes in tail temperature, indicative of vasoactive effector responses, did occur. PMID:8734995

Li, Q; Thornhill, J

1996-01-01

213

About the possible options for models of convective heat transfer in closed volumes with local heating source  

NASA Astrophysics Data System (ADS)

Results of mathematical modeling of convective heat transfer in air area surrounded on all sides enclosing structures, in the presence of heat source at the lower boundary of the media are presented. Solved the system of differential equations of unsteady Navier-Stokes equations with the appropriate initial and boundary conditions. The process of convective heat transfer is calculated using the models of turbulence Prandtl and Prandtl-Reichard. Takes into account the processes of heat exchange region considered with the environment. Is carried out the analysis of the dimensionless heat transfer coefficient at interfaces "air - enclosures". The distributions average along the gas temperature range are obtained.

Maksimov, Vyacheslav I.; Nagornova, Tatiana A.; Shestakov, Igor A.

2015-01-01

214

Geoneutrinos and Heat Production in the Earth: Constraints and Implications  

SciTech Connect

Recent results from antineutrino (geoneutrino) studies at KamLAND are coincident with geochemical models of Th and U in the Earth. KamLAND and Borexino detectors are on line, thus uncertainties in counting statistics will be reduced as data are accumulated. The SNO+ detector, situated in the middle of the North American plate will come on line in {approx}3 yrs and will be best suited to yield a precise estimate of the continental contribution to the Earth's Th & U budget. The distribution of heat producing elements in the Earth drives convection and plate tectonics. Geochemical models posit that {approx}40% of the heat producing elements are in the continental crust, with the remainder in the mantle. Although models of core formation allow for the incorporation of heat producing elements, the core contribution of radiogenic heating is considered to be negligible. Most parameterized convection models for the Earth require significant amounts of radiogenic heating of the Earth, a factor of two greater than geochemical models predict. The initial KamLAND results challenge these geophysical models and support geochemical models calling for a significant contribution from secular cooling of the mantle.

McConough, Bill (University of Maryland) [University of Maryland

2008-07-02

215

Geoneutrinos and Heat Production in the Earth: Constraints and Implications  

SciTech Connect

Recent results from antineutrino (geoneutrino) studies at KamLAND are coincident with geochemical models of Th and U in the Earth.  KamLAND and Borexino detectors are on line, thus uncertainties in counting statistics will be reduced as data are accumulated.  The SNO+ detector, situated in the middle of the North American plate will come on line in ~3 yrs and will be best suited to yield a precise estimate of the continental contribution to the Earth’s Th & U budget.  The distribution of heat producing elements in the Earth drives convection and plate tectonics.  Geochemical models posit that ~40% of the heat producing elements are in the continental crust, with the remainder in the mantle.  Although models of core formation allow for the incorporation of heat producing elements, the core contribution of radiogenic heating is considered to be negligible.  Most parameterized convection models for the Earth require significant amounts of radiogenic heating of the Earth, a factor of two greater than geochemical models predict.  The initial KamLAND results challenge these geophysical models and support geochemical models calling for a significant contribution from secular cooling of the mantle.

Bill McDonough

2008-07-02

216

Geoneutrinos and Heat Production in the Earth: Constraints and Implications  

ScienceCinema

Recent results from antineutrino (geoneutrino) studies at KamLAND are coincident with geochemical models of Th and U in the Earth.  KamLAND and Borexino detectors are on line, thus uncertainties in counting statistics will be reduced as data are accumulated.  The SNO+ detector, situated in the middle of the North American plate will come on line in ~3 yrs and will be best suited to yield a precise estimate of the continental contribution to the Earth?s Th & U budget.  The distribution of heat producing elements in the Earth drives convection and plate tectonics.  Geochemical models posit that ~40% of the heat producing elements are in the continental crust, with the remainder in the mantle.  Although models of core formation allow for the incorporation of heat producing elements, the core contribution of radiogenic heating is considered to be negligible.  Most parameterized convection models for the Earth require significant amounts of radiogenic heating of the Earth, a factor of two greater than geochemical models predict.  The initial KamLAND results challenge these geophysical models and support geochemical models calling for a significant contribution from secular cooling of the mantle.

Bill McDonough

2010-01-08

217

The use of nickel/aluminum explosively reactive nanolayers as localized heat sources in solder joints  

NASA Astrophysics Data System (ADS)

Although solder reflow continues to be the current state of the art in joining technology, conventional reflow makes use of furnace heating, in which all components must be exposed to temperatures higher than the melting temperature of the solder. Damaging temperature sensitive components and thermal stresses involved in joining materials of different thermal expansion coefficients are critical drawbacks in using furnace heating. An alternative heat source is provided by Ni/Al reactive nanolayer foils, which is a material comprised of thousands of alternating, nanoscale layers of Al and Ni. A small pulse of energy in the form of an electric spark ignites the reaction by initiating interlayer atomic diffusion. The reaction between these layers is exothermic, releasing enough heat to allow the reaction to propagate through the remainder of the sample. Due to its shape and localized nature of heat released, solder can be melted without heating layers beyond the solder, such as temperature sensitive bond components. In this study, a process is developed to integrate Ni/Al reactive nanolayer foils into bond structures using materials in current technologies. Si/solder/Si and Cu/solder/Cu solder joints are fabricated by reactive nanolayer soldering and are used to study the microstructure and mechanical properties. The microstructural and chemical analysis are performed using scanning and transmission electron microscopy and as well as X-Ray diffraction and energy dispersive analysis, respectively. Single-lap shear testing, through-thickness tensile testing, in-situ nanocompression, and nanoindentation are used to characterize the mechanical strength. Ni/Al nanolayers become a single phase, nanocrystalline NiAl phase as a result of the explosive reaction. The wetting of Sn-based solders is good on this layer, as evidenced by the interlocking branched microstructure as well as the formation of Ni3Sn4 at the interface. A joint shear strength of approximately 30 MPa was yielded when the initial temperature was 70°C and the applied pressure was 15 MPa. In-situ nanocompression results show the direct observation of <110> slip and nanoindentation analysis showed that the NiAI layer has large compressive residual stress.

Tong, Michael Shou-Ming

218

HEAT PRODUCTION FROM FORAGING ACTIVITY CONTRIBUTES TO THERMOREGULATION IN BLACK-CAPPED CHICKADEES  

Microsoft Academic Search

We measured metabolic heat produc- tion (Hm) of perching and foraging Black-capped Chickadees (Poecile atricapillus) to determine if the heat produced during foraging activity, or exercise thermogenesis, could replace thermoregulatory heat production requirements. Hm and activity of chick- adees in winter were measured at ambient tempera- tures (Ta) ranging from 211.5u to 15.5uC. Mean activity amplitude recorded with an activity

SHELDON J. COOPER; SARAH SONSTHAGEN

2007-01-01

219

Heat losses in a CVD reactor for polysilicon production: Comprehensive model and experimental validation  

NASA Astrophysics Data System (ADS)

This work addresses heat losses in a CVD reactor for polysilicon production. Contributions to the energy consumption of the so-called Siemens process are evaluated, and a comprehensive model for heat loss is presented. A previously-developed model for radiative heat loss is combined with conductive heat loss theory and a new model for convective heat loss. Theoretical calculations are developed and theoretical energy consumption of the polysilicon deposition process is obtained. The model is validated by comparison with experimental results obtained using a laboratory-scale CVD reactor. Finally, the model is used to calculate heat consumption in a 36-rod industrial reactor; the energy consumption due to convective heat loss per kilogram of polysilicon produced is calculated to be 22-30 kWh/kg along a deposition process.

Ramos, A.; Rodríguez, A.; del Cañizo, C.; Valdehita, J.; Zamorano, J. C.; Luque, A.

2014-09-01

220

Using heat demand prediction to optimise Virtual Power Plant production capacity  

E-print Network

- generators, the electricity production is determined by heat demand. In this paper we propose a VPP control distributed electricity generation (micro- generation) is expected. Micro-generators are small appliances that generate electricity (and heat) at the kilowatt level, which allows them to be installed in households

Al Hanbali, Ahmad

221

Performance evaluation of adding ethanol production into an existing combined heat and power plant.  

PubMed

In this paper, the configuration and performance of a polygeneration system are studied by modelling the integration of a lignocellulosic wood-to-ethanol process with an existing combined heat and power (CHP) plant. Data from actual plants are applied to validate the simulation models. The integrated polygeneration system reaches a total efficiency of 50%, meeting the heating load in the district heating system. Excess heat from the ethanol production plant supplies 7.9 MW to the district heating system, accounting for 17.5% of the heat supply at full heating load. The simulation results show that the production of ethanol from woody biomass is more efficient when integrated with a CHP plant compared to a stand-alone production plant. The total biomass consumption is reduced by 13.9% while producing the same amounts of heat, electricity and ethanol fuel as in the stand-alone configurations. The results showed that another feature of the integrated polygeneration system is the longer annual operating period compared to existing cogeneration. Thus, the renewable electricity production is increased by 2.7% per year. PMID:19758800

Starfelt, F; Thorin, E; Dotzauer, E; Yan, J

2010-01-01

222

Effects of Heat Stress on Egg Production and Quality in Two Strains of Layers  

Technology Transfer Automated Retrieval System (TEKTRAN)

Heat stress is a problem for both egg production and bird well-being. Given a stressor, genetic differences can alter the type and degree of birds’ responses and their adaptation. This study examined heat stress responses of two strains of White Leghorns: DeKalb XL (DXL), an individually-selected, c...

223

FARM NET INCOME IMPACT OF SWITCHGRASS PRODUCTION AND CORN STOVER COLLECTION FOR HEAT AND POWER GENERATION  

E-print Network

and Corn Stover Collection for Heat and Power Generation Mitchell A. Myhre Advisor: Associate ProfessorFARM NET INCOME IMPACT OF SWITCHGRASS PRODUCTION AND CORN STOVER COLLECTION FOR HEAT AND POWER GENERATION by Mitchell A. Myhre A thesis submitted in partial fulfillment of the requirements for the degree

Wisconsin at Madison, University of

224

Genetic variations alter production and behavioral responses following heat stress in two strains of laying hens  

Technology Transfer Automated Retrieval System (TEKTRAN)

Heat stress is a problem for both egg production and hen well-being. Given a stressor, genetic differences alter the type and degree of hens’ responses and their adaptation. This study examined heat stress responses of two strains of White Leghorns: Dekalb XL (DXL), a commercial strain individually ...

225

The use of plate heat exchangers to improve energy efficiency in phosphoric acid production  

Microsoft Academic Search

This paper originated as a part of a comprehensive research project designed to develop ecologically sustainable, environmentally friendly, resource- and energy-saving industrial process technology for the production of a wide class of phosphorus containing substances. The essential feature of the research was designed for the replacement of tubular heat exchangers with Plate heat exchangers (PHEs) and for the installation of

Petro Kapustenko; Stanislav Boldyryev; Olga Arsenyeva; Gennadiy Khavin

2009-01-01

226

Nonmodal and nonlinear dynamics of a volatile liquid film flowing over a locally heated surface  

NASA Astrophysics Data System (ADS)

The stability of a thin, volatile liquid film falling under the influence of gravity over a locally heated, vertical plate is analyzed in the noninertial regime using a model based on long-wave theory. The model is formulated to account for evaporation that is either governed by thermodynamic considerations at the interface in the one-sided limit or limited by the rate of mass transfer of the vapor from the interface. The temperature gradient near the upstream edge of the heater induces a gradient in surface tension that opposes the gravity-driven flow, and a pronounced thermocapillary ridge develops in the streamwise direction. Recent theoretical analyses predict that the ridge becomes unstable above a critical value of the Marangoni parameter, leading to the experimentally observed rivulet structure that is periodic in the direction transverse to the bulk flow. An oscillatory, thermocapillary instability in the streamwise direction above the heater is also predicted for films with sufficiently large heat loss at the free surface due to either evaporation or strong convection in the adjoining gas. This present work extends the recent linear stability analysis of such flows by Tiwari and Davis [Phys. Fluids 21, 022105 (2009)] to a nonmodal analysis of the governing non-self-adjoint operator and computations of the nonlinear dynamics. The nonmodal analysis identifies the most destabilizing perturbations to the film and their maximum amplification. Computations of the nonlinear dynamics reveal that small perturbations can be sufficient to destabilize a linearly stable film for a narrow band of wave numbers predicted by the nonmodal, linearized analysis. This destabilization is linked to the presence of stable, discrete modes that appear as the Marangoni parameter approaches the critical value at which the film becomes linearly unstable. Furthermore, the thermocapillary instability leads to a new, time-periodic base state. This transition corresponds to a Hopf bifurcation with increasing Marangoni parameter. A linear stability analysis of this time-periodic state reveals further instability to transverse perturbations, with the wave number of the most unstable mode about 50% smaller than for the rivulet instability of the steady base state and exponential growth rate about three times larger. The resulting film behavior is reminiscent of inertial waves on locally heated films, although the wave amplitude is larger in the present case near the heater and decays downstream where the Marangoni stress vanishes. The film's heat transfer coefficient is found to increase significantly upon the transition to the time-periodic flow.

Tiwari, Naveen; Davis, Jeffrey M.

2009-10-01

227

Production of multicharged iron ions with inductively heated vapor source  

Microsoft Academic Search

Multiply charged Fe ions are produced from solid material in a 2.45 GHz electron cyclotron resonance (ECR) ion source. We develop an evaporator by induction heating with an induction coil covered by ceramics in vacuum and surrounding the pure Fe rod with noncontact. The typical power and the frequency of the induction currents range from 300 to 800 W and

Yushi Kato; Masashi Tomida; Takashi Kubo; Toyohisa Asaji; Kiyokatsu Tanaka; Fuminobu Sato; Toshiyuki Iida

2006-01-01

228

Metabolic heat production in electrically stimulated and non-stimulated muscle  

E-print Network

METABOLIC HEAT PRODUCTION IN ELECTRICALLY STIMULATED AND NON-STIMULATED MUSCLE A Thesis by ROY JAMES FITZWATER Submitted to the Graduate College of Texas AAM University in partial fufillment of the requirement for the degree of MASTER CF... SCIENCE August 1980 Major Subject: Food Science and Technology METABOLIC HEAT PRODUCTION IN ELECTRICALLY STIMULATED . AND NON-STIMULATED MUSCLE A Thesis . by ROY JAMES FITZWATER Approved as to style and content by: (Co-chai n of Committee) (Co...

Fitzwater, Roy James

1980-01-01

229

Image grid errors due to the application of a local heat source on the TIR surface of a prism  

NASA Astrophysics Data System (ADS)

The sensitivity of an image position grid to local heat applied to the TIR surface of a prism in a Wynne Dyson design was examined. The mechanisms resulting in the shape and magnitude of the shape change are explored qualitatively and with FEA analysis. The FEA package was used to generate temperature and deformation results, which were then ported to a ray trace program and the impact on the image grid was determined. A device was made to check the validity of the models. The heat load was applied by inserting thermocouple instrumented Watlow cartridge heaters in an aluminum block, placing the aluminum block 127 microns from the TIR surface, and heating an 8mm square surface area of the block to 1.3C, 2.5C and 5.0C. These heat loads resulted in peak image errors of 68nm/C with vector error maps in an annular pattern roughly centered on the geometrical center of the heat load. The models developed were useful for qualitative predictions of the performance, but need tuning to increase the accuracy. Although linear superposition cannot be used to calculate the effect of combined local heat sources, due to the non-linear behavior of the thermal effects, the results can be used to estimate the maximum stray local heat that can be tolerated on this optical surface.

Sumner, Roger C.; Zhang, Shiyu

2004-10-01

230

A complex variable meshless local Petrov—Galerkin method for transient heat conduction problems  

NASA Astrophysics Data System (ADS)

On the basis of the complex variable moving least-square (CVMLS) approximation, a complex variable meshless local Petrov—Galerkin (CVMLPG) method is presented for transient heat conduction problems. The method is developed based on the CVMLS approximation for constructing shape functions at scattered points, and the Heaviside step function is used as a test function in each sub-domain to avoid the need for a domain integral in symmetric weak form. In the construction of the well-performed shape function, the trial function of a two-dimensional (2D) problem is formed with a one-dimensional (1D) basis function, thus improving computational efficiency. The numerical results are compared with the exact solutions of the problems and the finite element method (FEM). This comparison illustrates the accuracy as well as the capability of the CVMLPG method.

Wang, Qi-Fang; Dai, Bao-Dong; Li, Zhen-Feng

2013-08-01

231

Local heat activation of single myosins based on optical trapping of gold nanoparticles.  

PubMed

Myosin is a mechano-enzyme that hydrolyzes ATP in order to move unidirectionally along actin filaments. Here we show by single molecule imaging that myosin V motion can be activated by local heat. We constructed a dark-field microscopy that included optical tweezers to monitor 80 nm gold nanoparticles (GNP) bound to single myosin V molecules with nanometer and submillisecond accuracy. We observed 34 nm processive steps along actin filaments like those seen when using 200 nm polystyrene beads (PB) but dwell times (ATPase activity) that were 4.5 times faster. Further, by using DNA nanotechnology (DNA origami) and myosin V as a nanometric thermometer, the temperature gradient surrounding optically trapped GNP could be estimated with nanometer accuracy. We propose our single molecule measurement system should advance quantitative analysis of the thermal control of biological and artificial systems like nanoscale thermal ratchet motors. PMID:25736894

Iwaki, Mitsuhiro; Iwane, Atsuko H; Ikezaki, Keigo; Yanagida, Toshio

2015-04-01

232

Simulation Study of Toroidal Shear Flow Generation by a Local ICRF Heating  

NASA Astrophysics Data System (ADS)

The toroidal shear flow generation by a local ICRF heating is studied using GNET code, in which the drift kinetic equation is solved in 5D phase-space. Verification of the Ohkawa model [T. Ohkawa and Miller, Phys. Plasmas 12 (2005) 094506.] predicting the toroidal shear flow generation is done including the finite orbit effect of energetic ions in a tokamak configuration. The Alcator C-mod plasma is assumed as a first step. A co-directional toroidal flow outside of the power absorption region (resonance position) is observed. The dominant part of toroidal flow dose not depend on the sign k// and this fact indicates that the driving mechanism of the dominant part is different from that proposed by the Ohkawa model.

Murakami, S.; Itoh, K.; Yamamoto, T.; Fukuyama, A.

2009-11-01

233

Origin, distribution and glaciological implications of Jurassic high heat production granites in the Weddell Sea rift, Antarctica  

NASA Astrophysics Data System (ADS)

The distribution of heat flow in Antarctic continental crust is critical to understanding ice sheet nucleation, growth and basal rheology and hydrology. We identify a group of High Heat Production granites intruded into Palaeozoic sedimentary sequences which may contribute to locally high heat flow beneath the central part of the West Antarctic Ice Sheet. Four of the granite plutons are exposed above ice sheet level at Pagano Nunatak, Pirrit Hills, Nash Hills and Whitmore Mountains. A new U-Pb zircon age from Pirrit Hills of 177.9 ± 2.3 Ma confirms earlier Rb-Sr dating that suggested an Early-Middle Jurassic age for the granites, coincident with the Karoo-Ferrar large igneous province and the first stage of Gondwana break-up. Our recently-acquired aerogeophysical data indicate that the plutons are distributed unevenly over 1000 km2 and were intruded into the actively extending, locally transcurrent, Jurassic Weddell Sea Rift [1]. In the NW part of the rift, the Pirrit Hills, Nash Hills and Whitmore Mountains granites form small isolated intrusions within weakly deformed upper crust. In the SE part of the rift, where granite intrusion was strongly structurally controlled within transtensional structures, the Pagano Nunatak granite is the only outcrop of a probably multiphase, ca 180 km long granite intrusion. The granites are weakly peraluminous, S-type and have Th and U abundances up to 61 and 19 ppm respectively. Heat production of analysed granite samples is ca. 2.9-9.1 µWm-3, toward the upper limit of values for High Heat Production granites globally. The granites are thought to have been generated during mafic underplating of the Weddell Rift during eruption of the contemporaneous Karoo-Ferrar magmatism [2]. The high Th and U abundances may be related to fractionation of the high Th-U Ferrar basaltic magmas combined with assimilation of pelitic sedimentary rocks. The granites correspond to an area of West Antarctica that may have heat flow significantly above the Antarctic average, as predicted from satellite magnetic data [3]. [1] Jordan, T.A., et al., Inland extent of the Weddell Sea Rift imaged by new aerogeophysical data, Tectonophysics (2012), 10.1016/j.tecto.2012.09.010 [2] Storey, B.C., et al., Middle Jurassic within-plate granites in West Antarctica and their bearing on the break-up of Gondwanaland. J. Geol. Soc. Lond, (1988), 145, 999-1007. [3] Fox Maule, C., et al., Heat flux anomalies in Antarctica revealed by satellite magnetic data. Science (2005), 10.1126/science.1106888

Leat, Phil T.; Jordan, Tom A. R. M.; Ferraccioli, Fausto; Flowerdew, Michael; R, Riley, Teal; Vaughan, Alan P. M.; Whitehouse, Martin

2013-04-01

234

A comparison of microwave versus direct solar heating for lunar brick production  

NASA Technical Reports Server (NTRS)

Two processing techniques considered suitable for producing bricks from lunar regolith are examined: direct solar heating and microwave heating. An analysis was performed to compare the two processes in terms of the amount of power and time required to fabricate bricks of various sizes. Microwave heating was shown to be significantly faster than solar heating for rapid production of realistic-size bricks. However, the relative simplicity of the solar collector(s) used for the solar furnace compared to the equipment necessary for microwave generation may present an economic tradeoff.

Yankee, S. J.; Strenski, D. G.; Pletka, B. J.; Patil, D. S.; Mutsuddy, B. C.

1990-01-01

235

Controlled Cavitation for Scale-Free Heating, Gum Hydration and Emulsification in Food and Consumer Products  

Microsoft Academic Search

\\u000a Cavitation is defined as the sudden formation and collapse of bubbles in liquid by means of a mechanical force. As bubbles\\u000a rapidly form and collapse, pressurized shock waves, localized heating events and tremendous shearing forces occur. As microscopic\\u000a cavitation bubbles are produced and collapse, shockwaves are given off into the liquid, which can result in heating and\\/or\\u000a mixing, similar to

Douglas G. Mancosky; Paul Milly

2011-01-01

236

Local sweating on the forehead, but not forearm, is influenced by aerobic fitness independently of heat balance requirements during exercise.  

PubMed

The present study investigated the influence of maximal oxygen uptake (V(O2 max)) on local steady-state sudomotor responses to exercise, independently of evaporative requirements for heat balance (E(req)). Eleven fit (F; (V(O2 max))61.9 ± 6.0 ml kg(-1) min(-1)) and 10 unfit men (UF; (V(O2 max)) 40.4 ± 3.8 ml kg(-1) min(-1)) cycled for 60 min at an air temperature of 24.5 ± 0.8°C and ambient humidity of 0.9 ± 0.3 kPa at a set metabolic heat production per unit surface area, producing the same E(req) in all participants (BAL trial) and, in a second trial, at 60% of (V(O2 max)). During the BAL trial, absolute power (F 107 ± 2 and UF 102 ± 2 W; P = 0.126), E(req) (F 175 ± 5 and UF 176 ± 9 W m(-2); P = 0.855), steady-state whole-body sweat rate (F 0.44 ± 0.02 and UF 0.47 ± 0.02 mg cm(-2) min(-1); P = 0.385) and local sweat rate on the arm (F 0.29 ± 0.03 and UF 0.35 ± 0.03 mg cm(-2) min(-1); P = 0.129) were not different between groups; however, local sweat rate on the forehead in UF (1.67 ± 0.20 mg cm(-2) min(-1)) was almost double (P = 0.002) that of F (0.87 ± 0.11 mg cm(-2) min(-1)). Heart rate, ratings of perceived exertion and relative exercise intensity were also significantly greater in UF (P < 0.05). There was a trend towards an elevated minute ventilation in UF (P = 0.052), while end-tidal P(CO2) was significantly lower in UF (P = 0.028). At 60% (V(O2 max)), absolute power (F 174 ± 6 and UF 110 ± 5 W; P < 0.001), E(req) (F 291 ± 14 and UF 190 ± 17 W m(-2); P < 0.001), steady-state whole-body sweat rate (F 0.84 ± 0.05 and UF 0.53 ± 0.03 mg cm(-2) min(-1); P < 0.001) and local sweat rate on the arm (F 0.75 ± 0.04 and UF 0.35 ± 0.03 mg cm(-2) min(-1); P < 0.001) and on the forehead (F 2.92 ± 0.42 and UF 1.68 ± 0.23 mg cm(-2) min(-1); P = 0.022) were all significantly greater in F compared with UF. Heart rate and ratings of perceived exertion were similar at all time points (P > 0.05). Significantly greater minute ventilation (P < 0.001) and end-tidal P (CO2) responses (P = 0.017) were found in F. In conclusion, aerobic fitness alters local sweating on the forehead, but not the forearm, independently of evaporative requirements for heat balance, and may be the result of differential control of sweating in these skin areas associated with the relative intensity of exercise. PMID:22227199

Cramer, Matthew N; Bain, Anthony R; Jay, Ollie

2012-05-01

237

Invisible but viable: recognising local markets for non-timber forest products  

Microsoft Academic Search

SUMMARY An emphasis on global markets for non-timber forest products (NTFPs) often overshadows attention to the local trade in many traditionally important products. Inattention to local markets can result in diminished appreciation of their role in supporting livelihoods and potentially lead to further marginalisation of the low-income groups involved. This paper draws on the literature and the research experience of

S. SHACKLETON; P. SHANLEY; O. NDOYE

2007-01-01

238

Territorial externalities in Local Agro-Food Systems of typical food products Sanz Caada, J.  

E-print Network

Territorial externalities in Local Agro-Food Systems of typical food products Sanz Cañada, J. ISDA 2010, Montpellier, June 28-30, 2010 - 0 - TERRITORIAL EXTERNALITIES IN LOCAL AGRO-FOOD SYSTEMS externalities created by the economic and institutional activities of Local Agro-Food Systems (LAFS

Paris-Sud XI, Université de

239

Localized heating of electrons in ionization zones: Going beyond the Penning-Thornton paradigm in magnetron sputtering  

NASA Astrophysics Data System (ADS)

The fundamental question of how energy is supplied to a magnetron discharge is commonly answered by the Penning-Thornton paradigm invoking secondary electrons. Recently, Huo and coworkers (Plasma Sources Sci. Technol. 22, 045005 (2013)) used a global discharge model to show that electron heating in the electric field of the magnetic presheath is dominant over heating by secondary electrons. In this contribution, this concept is applied locally taking into account the electric potential structure of ionization zones. Images of ionization zones can and should be interpreted as diagrams of the localization of high electric potential and related electron energy.

Anders, André

2014-12-01

240

Local heat and cold application after eastern cottonmouth moccasin (Agkistrodon piscivorus) envenomation in the rat: effect on tissue injury.  

PubMed

We studied the effect of local application of heat or cold on the development of tissue necrosis in envenomated rats. Anesthetized animals had 6 mg/kg venom from Agkistrodon piscivorus injected subcutaneously into the lateral aspect of a hind limb. Heat or cold was applied to the site of envenomation in the experimental groups for 4-6 hr, and the injected area was examined histologically after 24 hr. Neither local treatment, with or without the presence of systemic antivenin, significantly affected the severity of tissue necrosis induced by the venom in comparison to a control group left at ambient temperature. PMID:1485335

Cohen, W R; Wetzel, W; Kadish, A

1992-11-01

241

Nuclear localization of the testis determining gene product SRY  

PubMed Central

We have studied the expression of the human SRY protein (termed p27SRY) in two different cell lines by using specific antibodies. Confocal microscopy enabled us to localize p27SRY precisely in the nucleus in a discrete punctuate pattern. Furthermore, through microinjection experiments, we have demonstrated that the localization of the p27SRY protein into the nucleus was an event involving the NH2-terminal part of the high mobility group (HMG) domain. With the help of several synthetic peptides and various p27SRY mutants, we have characterized a bipartite basic motif in this part of the protein corresponding to a nuclear localization signal. This nuclear localization signal appears to be highly conserved in SRY box- and HMB box-containing proteins, suggesting common properties of nuclear targeting within the HMG box protein family. PMID:7876301

1995-01-01

242

Increasing bioenergy production on arable land: Does the regional and local climate respond? Germany as a case study  

NASA Astrophysics Data System (ADS)

The extent and magnitude of land cover change effect on local and regional future climate during the vegetation period due to different forms of bioenergy plants are quantified for extreme temperatures and energy fluxes. Furthermore, we vary the spatial extent of plant allocation on arable land and simulate alternative availability of transpiration water to mimic both rainfed agriculture and irrigation. We perform climate simulations down to 1 km scale for 1970-1975 C20 and 2070-2075 A1B over Germany with Consortium for Small-Scale Modeling in Climate Mode. Here an impact analysis indicates a strong local influence due to land cover changes. The regional effect is decreased by two thirds of the magnitude of the local-scale impact. The changes are largest locally for irrigated poplar with decreasing maximum temperatures by 1°C in summer months and increasing specific humidity by 0.15 g kg-1. The increased evapotranspiration may result in more precipitation. The increase of surface radiative fluxes Rnet due to changes in latent and sensible heat is estimated by 5 W m-2locally. Moreover, increases in the surface latent heat flux cause strong local evaporative cooling in the summer months, whereas the associated regional cooling effect is pronounced by increases in cloud cover. The changes on a regional scale are marginal and not significant. Increasing bioenergy production on arable land may result in local temperature changes but not in substantial regional climate change in Germany. We show the effect of agricultural practices during climate transitions in spring and fall.

Tölle, Merja H.; Gutjahr, Oliver; Busch, Gerald; Thiele, Jan C.

2014-03-01

243

On local equivalence of star-products on Poisson manifolds  

E-print Network

We present a proof that every star-product defined on a Poisson manifold and written in a given quantum canonical coordinate system is uniquely equivalent with a Moyal product associated with this coordinate system. The equivalence is assumed to satisfy some additional conditions which guarantee its uniqueness. Moreover, the systematic construction of such equivalence is presented and a formula for this equivalence in a case of a particular class of star-products is given, to the fourth order in $\\hbar$.

Ziemowit Domanski; Maciej Blaszak

2015-03-20

244

The Locality Axiom in Quantum Field Theory and Tensor Products of $C^*$-algebras  

E-print Network

The prototype of mutually independent systems are systems which are localized in spacelike separated regions. In the framework of locally covariant quantum field theory we show that the commutativity of observables in spacelike separated regions can be encoded in the tensorial structure of the functor which associates unital $C^*$-algebras (the local observable algebras) to globally hyperbolic spacetimes. This holds under the assumption that the local algebras satisfy the split property and involves the minimal tensor product of $C^*$-algebras.

Romeo Brunetti; Klaus Fredenhagen; Paniz Imani; Katarzyna Rejzner

2012-06-24

245

The Locality Axiom in Quantum Field Theory and Tensor Products of $C^*$-algebras  

E-print Network

The prototype of mutually independent systems are systems which are localized in spacelike separated regions. In the framework of locally covariant quantum field theory we show that the commutativity of observables in spacelike separated regions can be encoded in the tensorial structure of the functor which associates unital $C^*$-algebras (the local observable algebras) to globally hyperbolic spacetimes. This holds under the assumption that the local algebras satisfy the split property and involves the minimal tensor product of $C^*$-algebras.

Brunetti, Romeo; Imani, Paniz; Rejzner, Katarzyna

2012-01-01

246

Hydrogen production and microbial diversity in sewage sludge fermentation preceded by heat and alkaline treatment.  

PubMed

Combined pretreatment of heat treatment with alkaline condition was applied to the sewage sludge in order to acquire the effective method for sludge solubilization and bio-hydrogen production. Solubilization ratio of the sludge with heat treatment at alkaline condition (pH 13) was as high as 85.0%, resulting in an increase of COD concentration in aqueous solution, but the ratio of sludge with heat treatment or alkaline treatment alone was 32.2% and 56.3%, respectively. During the fermentation of the pretreated sludge, a significant increase of hydrogen production was observed with a low strength of ammonia, showing that ammonia in the aqueous phase could inhibit bio-hydrogen production. Klebsiella, Enterobacter or Clostridium genus were mostly related on the hydrogen production. PMID:22306077

Kang, Jung-Hyun; Kim, Daekeun; Lee, Tae-Jin

2012-04-01

247

Profile shape optimization in multi-jet impingement cooling of dimpled topologies for local heat transfer enhancement  

NASA Astrophysics Data System (ADS)

The present study deals with shape optimization of dimples on the target surface in multi-jet impingement heat transfer. Bezier polynomial formulation is incorporated to generate profile shapes for the dimple profile generation and a multi-objective optimization is performed. The optimized dimple shape exhibits higher local Nusselt number values compared to the reference hemispherical dimpled plate optimized shape which can be used to alleviate local temperature hot spots on target surface.

Negi, Deepchand Singh; Pattamatta, Arvind

2014-08-01

248

Profile shape optimization in multi-jet impingement cooling of dimpled topologies for local heat transfer enhancement  

NASA Astrophysics Data System (ADS)

The present study deals with shape optimization of dimples on the target surface in multi-jet impingement heat transfer. Bezier polynomial formulation is incorporated to generate profile shapes for the dimple profile generation and a multi-objective optimization is performed. The optimized dimple shape exhibits higher local Nusselt number values compared to the reference hemispherical dimpled plate optimized shape which can be used to alleviate local temperature hot spots on target surface.

Negi, Deepchand Singh; Pattamatta, Arvind

2015-04-01

249

Short-term exercise training does not improve whole-body heat loss when rate of metabolic heat production is considered  

Microsoft Academic Search

We evaluated the effects of an 8-week exercise training program in previously sedentary individuals on whole-body heat balance\\u000a during exercise at a constant rate of metabolic heat production. Prior to and after 8 weeks of training, ten participants\\u000a performed 60-min of cycling exercise at a constant rate of heat production (~450 W) followed by 60-min of recovery, at 30°C\\u000a and 15%

Jill Stapleton; Daniel Gagnon; Glen P. Kenny

2010-01-01

250

Heat Production During Countermeasure Exercises Planned for the International Space Station  

NASA Technical Reports Server (NTRS)

This investigation's purpose was to determine the amount of heat produced when performing aerobic and resistance exercises planned as part of the exercise countermeasures prescription for the ISS. These data will be used to determine thermal control requirements of the Node 1 and other modules where exercise hardware might reside. To determine heat production during resistive exercise, 6 subjects using the iRED performed 5 resistance exercises which form the core exercises of the current ISS resistive exercise countermeasures. Each exerciser performed a warm-up set at 50% effort, then 3 sets of increasing resistance. We measured oxygen consumption and work during each exercise. Heat loss was calculated as the difference between the gross energy expenditure (minus resting metabolism) and the work performed. To determine heat production during aerobic exercise, 14 subjects performed an interval, cycle exercise protocol and 7 subjects performed a continuous, treadmill protocol. Each 30-min. exercise is similar to exercises planned for ISS. Oxygen consumption monitored continuously during the exercises was used to calculate the gross energy expenditure. For cycle exercise, work performed was calculated based on the ergometer's resistance setting and pedaling frequency. For treadmill, total work was estimated by assuming 25% work efficiency and subtracting the calculated heat production and resting metabolic rate from the gross energy expenditure. This heat production needs to be considered when determining the location of exercise hardware on ISS and designing environmental control systems. These values reflect only the human subject s produced heat; heat produced by the exercise hardware also will contribute to the heat load.

Rapley, Michael G.; Lee, Stuart M. C.; Guilliams, Mark E.; Greenisen, Michael C.; Schneider, Suzanne M.

2004-01-01

251

Local Rural Product as a "Relic" Spatial Strategy in Globalised Rural Spaces: Evidence from County Clare (Ireland)  

ERIC Educational Resources Information Center

Using a case study from County Clare (Ireland), this study critically analyses notions of "local" rural production. It investigates where rural businesses source the different components of their products and how these interrelate with the locality, how local businesses use the notion of "local" in their product branding, and what the…

Wilson, Geoff A.; Whitehead, Ian

2012-01-01

252

Study of heat production and transfer in shredded tires  

NASA Astrophysics Data System (ADS)

The purpose of this study is to determine the cause(s) of initial exothermic reactions in shredded tire. The primary hypothesis was that the oxidation of exposed steel wires, the oxidation of rubber, or sulfur causes the exothermic reactions in shredded tire. Laboratory tests were conducted to determine the heat transfer properties of the shredded tires by using a hot-plate apparatus. The experiments were conducted by varying the physical and environmental conditions as follows: (1) Tire size, (2) Wire content, (3) Water content, (4) Effective stress, (5) Air supply, (6) pH, (7) Humic Acid. First, laboratory testing was conducted to determine the effects of tire size on the heat transfer properties of shredded tires. The heat coefficient and diffusivity ranged from 3.0 to 3.5 W/m-K and 0.0002 to 0.00084 m 2/hour, respectively. Next, experiments were conducted to determine the effects of wire content on the exothermic reaction rate of tire shreds. When various amounts of wire (i.e., 5% to 15%) were exposed, the reaction rate increased, 2800 Btu for every lb of iron that is oxidized. In comparison, tire shreds with no wire were also tested under the same experimental conditions as above, however, no exothermic reaction occurred. These tests (i.e., with no wire) illustrate that carbon black in rubber molecule considers not oxidize. It was postulated that the reaction between iron in the wire and sulfur in the tire may be a potential cause of the exothermic reaction under low oxygen conditions. Experiments without air supply yielded no exothermic reaction. Thus, sulfur did not cause exotherm, because it is at low energy level and immobilized in the vulcanization process. In addition, experiments were conducted as the air supply was varied from 0 to 4 psi. With air pressure of less than 4-psi, no reaction occurred until 4-psi air was provided for the experiment. In conclusion, the design of an embankment with tire shreds should include shredded tires of bigger size without wire and the surface must be sealed to avoid any entrance of air into an embankment of shredded tires. Proper compact of the tire shreds should be conducted to reduce the air voids.

Sellassie, Kassahun G.

253

ENERGY PRODUCTION AND RESIDENTIAL HEATING: TAXATION, SUBSIDIES, AND COMPARATIVE COSTS  

EPA Science Inventory

This analysis is in support of the Ohio River Basin Energy Study (ORBES), a multidisciplinary policy research program supported by the Environmental Protection Agency. It examines the effect of economic incentives on public and private decisions affecting energy production and us...

254

Radiogenic heat production in the lithosphere of Sulu ultrahigh-pressure metamorphic belt  

NASA Astrophysics Data System (ADS)

The Chinese Continental Scientific Drilling (CCSD) project is located at the Sulu ultrahigh-pressure metamorphic (UHPM) belt. It offers a unique opportunity for studying the radiogenic heat production of both shallower and deeper rocks. Based on the concentrations of radiogenic elements U, Th and K on 349 samples from main hole of CCSD (CCSD MH), pilot holes and exposures, we determined radiogenic heat productions of all major rock types in the Sulu UHPM belt. Results show the mean values of orthogneiss and paragneiss are respectively 1.65 ± 0.81 and 1.24 ± 0.61 µW m - 3 . Due to different composition and grade of retrogressive metamorphism, the eclogites display significant scatter in radiogenic heat production, ranging from 0.01 to 2.85 µW m - 3 , with a mean of 0.44 ± 0.55 µW m - 3 . The radiogenic heat production in ultramafic rocks also varies within a large range of 0.02 to 1.76 µW m - 3 , and the average turns out to be 0.18 ± 0.31 µW m - 3 . Based on the measurements and crustal petrologic model, the vertical distribution model of heat production in Sulu crust is established. The resulting mean heat production (0.76 µW m - 3 ) contributes 24 mW m - 2 to the surface heat flow. 1-D thermal model indicates that the temperature at the Moho reaches above 750 °C, and the thermal thickness of the lithosphere is ~ 75 km, in good agreement with the geophysical results. The high teat flow (~ 75 mW m - 2 ) together with thin lithosphere presents strong support for the extension events during the late Cretaceous and Cenozoic.

He, Lijuan; Hu, Shengbiao; Yang, Wencai; Wang, Jiyang

2009-01-01

255

System for vaporizing carbon dioxide utilizing the heat by-product of the refrigeration system as a heat source  

SciTech Connect

The present invention is directed to a carbonation and refrigeration system wherein the heat of the refrigerant output side of the refrigeration compressor is utilized to vaporize liquid carbon dioxide into CO/sub 2/ gas which is introduced into a liquid product. The carbonation and refrigeration system successfully utilizes the heat of the refrigerant to vaporize the CO/sub 2/ liquid regardless of the cooling demand of the system caused by seasonal temperature variations. For example during the winter months when the cooling demand is as low as 10% of the cooling demand in the summer, the carbonation and refrigeration system operates effectively to vaporize the CO/sub 2/ liquid by means of a heat exchanger and a desuperheater which are connected in communication with the superheated vapor emerging from the output side of a refrigeration compressor. In addition, the carbonation and refrigeration system of the present invention cools more efficiently by extracting some of the heat from the condensed refrigerant entering the receiver of the refrigeration system. In this manner, the refrigeration compressor can operate more efficiently.

Shaw, H.L.

1980-12-23

256

Chloroplast small heat shock proteins: evidence for atypical evolution of an organelle-localized protein.  

PubMed

Knowledge of the origin and evolution of gene families is critical to our understanding of the evolution of protein function. To gain a detailed understanding of the evolution of the small heat shock proteins (sHSPs) in plants, we have examined the evolutionary history of the chloroplast (CP)-localized sHSPs. Previously, these nuclear-encoded CP proteins had been identified only from angiosperms. This study reveals the presence of the CP sHSPs in a moss, Funaria hygrometrica. Two clones for CP sHSPs were isolated from a F. hygrometrica heat shock cDNA library that represent two distinct CP sHSP genes. Our analysis of the CP sHSPs reveals unexpected evolutionary relationships and patterns of sequence conservation. Phylogenetic analysis of the CP sHSPs with other plant CP sHSPs and eukaryotic, archaeal, and bacterial sHSPs shows that the CP sHSPs are not closely related to the cyanobacterial sHSPs. Thus, they most likely evolved via gene duplication from a nuclear-encoded cytosolic sHSP and not via gene transfer from the CP endosymbiont. Previous sequence analysis had shown that all angiosperm CP sHSPs possess a methionine-rich region in the N-terminal domain. The primary sequence of this region is not highly conserved in the F. hygrometrica CP sHSPs. This lack of sequence conservation indicates that sometime in land plant evolution, after the divergence of mosses from the common ancestor of angiosperms but before the monocot-dicot divergence, there was a change in the selective constraints acting on the CP sHSPs. PMID:10588716

Waters, E R; Vierling, E

1999-12-01

257

Heat management for hydrogen production by high temperature steam electrolysis  

Microsoft Academic Search

Many research and development projects throughout the world are devoted to sustainable hydrogen production processes. Low-temperature electrolysis, when consuming electricity produced without greenhouse gas emissions, is a sustainable process, though having limited efficiency.The performance of electrolysis processes can be improved by functioning at high temperature (high-temperature electrolysis, HTE). This leads to a reduction in energy consumption but requires some of

Christine Mansilla; Jon Sigurvinsson; André Bontemps; Alain Maréchal; François Werkoff

2007-01-01

258

Laser doppler perfusion monitoring of skin blood flow at different depths in finger and arm upon local heating  

Microsoft Academic Search

The purpose of the study was to elucidate the vasodilatory response to local heating of the skin at two depths in two locations. To accomplish this, we measured skin blood flow in 12 healthy subjects using laser Doppler perfusion monitoring. A probe with two fibers separated 0.14 mm (superficial) and 0.25 mm (deeper) from the illuminating fiber was first attached

Carolin Freccero; Frank Holmlund; Siv Bornmyr; Jan Castenfors; Anne-Marie Johansson; Göran Sundkvist; Henry Svensson; Per Wollmer

2003-01-01

259

Theoretical study of heat and mass transfer in a zeolite bed during water desorption: validity of local thermal equilibrium assumption  

Microsoft Academic Search

We have studied heat and mass transfer in a zeolite bed during water desorption. For this purpose, a mathematical model based on scale changing has been established. We have tested the local thermal equilibrium assumption in a two-dimensional flow.The problem is numerically resolved using a finite volume method. The numerical simulation gives the time and space evolution of temperature and

A. Mhimid

1998-01-01

260

Experimental study and mathematical simulation of the mixed convection in a rectangular area with a local heat source and the heat sink at the external boundaries  

NASA Astrophysics Data System (ADS)

The results of the experimental determination of temperatures and numerical simulation of temperature fields in a mixed convection in a rectangular area with a heat-conducting walls at a local energy source on the bottom are presented. For the experimental determination of temperature fields in a mixed convection method of thermocouple measurements was used. Studies were conducted at Reynolds numbers 10 ?Re ? 1500 and Rayleigh 103 ?Ra ? 105. For the verification of obtained experimental data mathematical simulation of mixed convection in the region with the use of a software package Comsol Multiphysics is carried out. A good agreement between the results of experimental determination of the local characteristics of mixed convection in a rectangular volume with a local source of energy and heat-conducting walls with theoretical consequences obtained in the simulation of convective flows using a mathematical package is established. It makes it possible to make a conclusion about the possibility of application for the analysis of flow conditions of viscous heat-conducting gas of experimental procedure based on methods of thermocouple measurements. At the same time the developed approach to the experimental study of mixed convection is applicable in a wide enough range of the main flow parameters and the experimental conditions.

Maksimov, Vyacheslav I.; Nagornov, Dmitriy A.

2014-08-01

261

Vacuum evaporation treatment of digestate: full exploitation of cogeneration heat to process the whole digestate production.  

PubMed

Vacuum evaporation represents an interesting and innovative solution for managing animal waste surpluses in areas with high livestock density. To reduce operational costs, a key factor is the availability of an inexpensive source of heat, such as that coming from an anaerobic digestion (AD) plant. The aim of this study was to test vacuum evaporation for the treatment of cattle slurry digestate focusing on heat exploitation. Tests were performed with a pilot plant fed with the digestate from a full-scale AD plant. The results were used to evaluate if and how cogeneration heat can support both the AD plant and the subsequent evaporation of the whole daily digestate production in a full-scale plant. The concentrate obtained (12% total solids) represents 40-50% of the influent. The heat requirement is 0.44 kWh/kg condensate. Heat power availability exceeding the needs of the digestor ranges from 325 (in winter) to 585 kW (in summer) versus the 382 kW required for processing the whole digestate production. To by-pass fluctuations, we propose to use the heat coming from the cogenerator directly in the evaporator, tempering the digestor with the latent heat of distillation vapor. PMID:25098878

Guercini, S; Castelli, G; Rumor, C

2014-01-01

262

Theoretical Design of a Thermosyphon for Efficient Process Heat Removal from Next Generation Nuclear Plant (NGNP) for Production of Hydrogen  

SciTech Connect

The work reported here is the preliminary analysis of two-phase Thermosyphon heat transfer performance with various alkali metals. Thermosyphon is a device for transporting heat from one point to another with quite extraordinary properties. Heat transport occurs via evaporation and condensation, and the heat transport fluid is re-circulated by gravitational force. With this mode of heat transfer, the thermosyphon has the capability to transport heat at high rates over appreciable distances, virtually isothermally and without any requirement for external pumping devices. For process heat, intermediate heat exchangers (IHX) are required to transfer heat from the NGNP to the hydrogen plant in the most efficient way possible. The production of power at higher efficiency using Brayton Cycle, and hydrogen production requires both heat at higher temperatures (up to 1000oC) and high effectiveness compact heat exchangers to transfer heat to either the power or process cycle. The purpose for selecting a compact heat exchanger is to maximize the heat transfer surface area per volume of heat exchanger; this has the benefit of reducing heat exchanger size and heat losses. The IHX design requirements are governed by the allowable temperature drop between the outlet of the NGNP (900oC, based on the current capabilities of NGNP), and the temperatures in the hydrogen production plant. Spiral Heat Exchangers (SHE’s) have superior heat transfer characteristics, and are less susceptible to fouling. Further, heat losses to surroundings are minimized because of its compact configuration. SHEs have never been examined for phase-change heat transfer applications. The research presented provides useful information for thermosyphon design and Spiral Heat Exchanger.

Piyush Sabharwall; Fred Gunnerson; Akira Tokuhiro; Vivek Utgiker; Kevan Weaver; Steven Sherman

2007-10-01

263

High-power ELF radiation generated by modulated HF heating of the ionosphere can cause Earthquakes, Cyclones and localized heating  

E-print Network

Research Program (HAARP) is currently the most important facility used to generate extremely low frequency Generating electromagnetic radiation at extremely-low frequencies is difficult because the long wavelengths transmitter radiates a strong beam of high- frequency (HF) waves modulated at ELF. This HF heating modulates

Paris-Sud XI, Université de

264

An evaluation of alternate production methods for Pu-238 general purpose heat source pellets  

SciTech Connect

For the past half century, the National Aeronautics and Space Administration (NASA) has used Radioisotope Thermoelectric Generators (RTG) to power deep space satellites. Fabricating heat sources for RTGs, specifically General Purpose Heat Sources (GPHSs), has remained essentially unchanged since their development in the 1970s. Meanwhile, 30 years of technological advancements have been made in the applicable fields of chemistry, manufacturing and control systems. This paper evaluates alternative processes that could be used to produce Pu 238 fueled heat sources. Specifically, this paper discusses the production of the plutonium-oxide granules, which are the input stream to the ceramic pressing and sintering processes. Alternate chemical processes are compared to current methods to determine if alternative fabrication processes could reduce the hazards, especially the production of respirable fines, while producing an equivalent GPHS product.

Mark Borland; Steve Frank

2009-06-01

265

A (S)TEM Gas Cell Holder with Localized Laser Heating for In Situ Experiments  

SciTech Connect

The advent of aberration correction for transmission electron microscopy has transformed atomic resolution imaging into a nearly routine technique for structural analysis. Now an emerging frontier in electron microscopy is the development of in situ capabilities to observe reactions at atomic resolution in real time and within realistic environments. Here we present a new in situ gas cell holder that is designed for compatibility with a wide variety of sample type (i.e., dimpled 3-mm discs, standard mesh grids, various types of focused ion beam lamellae attached to half grids). Its capabilities include localized heating and precise control of the gas pressure and composition while simultaneously allowing atomic resolution imaging at ambient pressure. The results show that 0.25-nm lattice fringes are directly visible for nanoparticles imaged at ambient pressure with gas path lengths up to 20 ?m. Additionally, we quantitatively demonstrate that while the attainable contrast and resolution decrease with increasing pressure and gas path length, resolutions better than 0.2 nm should be accessible at ambient pressure with gas path lengths less than the 15 ?m utilized for these experiments.

Mehraeen, S.; McKeown, J.; Deshmukh, Pushkarraj V.; Evans, James E.; Abellan Baeza, Patricia; Xu, Pinghong; Reed, Bryan W.; Taheri, Mitra L.; Fischione, Paul E.; Browning, Nigel D.

2013-04-01

266

Analysis of Competitiveness and Support Instruments for Heat and Electricity Production from Wood Biomass in Latvia  

NASA Astrophysics Data System (ADS)

Utilisation of renewable energy sources is one of the key factors in a search for efficient ways of reducing the emissions of greenhouse gases and improving the energy supply security. So far, the district heating supply in Latvia has been based on natural gas, with the wood fuel playing a minor role; the same is true for decentralised combined heat-power (CHP) production. The paper describes a method for evaluation of the economic feasibility of heat and electricity production from wood biomass under the competition between different fuel types and taking into account the electricity market. For the simulation, a cost estimation model is applied. The results demonstrate that wood biomass can successfully be utilised for competitive heat production by boiler houses, while for electricity production by CHP utilities it cannot compete on the market (even despite the low prices on wood biomass fuel) unless particular financial support instruments are applied. The authors evaluate the necessary support level and the impact of two main support instruments - the investment subsidies and the feed-in tariff - on the economic viability of wood-fuelled CHP plants, and show that the feed-in tariff could be considered as an instrument strongly affecting the competitiveness of such type CHP. Regarding the feed-in tariff determination, a compromise should be found between the economy-dictated requirement to develop CHP projects concerning capacities above 5 MWel - on the one hand, and the relatively small heat loads in many Latvian towns - on the other.

Klavs, G.; Kudrenickis, I.; Kundzina, A.

2012-01-01

267

The effect of hyperosmolality on the rate of heat production of quiescent trabeculae isolated from the rat heart  

Microsoft Academic Search

A B ST R A C T We have measured the rate of heat production of isolated, quiescent, right ventricular trabeculae of the rat under isosmotic and hyperosmotic conditions, using a microcalorimetric technique. In parallel experi- ments, we measured force production and intracellular calcium concentration ((Ca2+)i). The rate of resting heat production under isosmotic conditions (mean +- SEM, n =

D. S. Loiselle; G. J. M. STIENEN; C. VAN HARDEVELD; E. T. VAN DER MEULEN; G. I. ZAHALAK; J. DAUT; G. ELZINGA

1996-01-01

268

New Concept for Internal Heat Production in Hot Jupiter Exo-Planets  

E-print Network

Discovery of hot Jupiter exo-planets, those with anomalously inflated size and low density relative to Jupiter, has evoked much discussion as to possible sources of internal heat production. But to date, no explanations have come forth that are generally applicable. The explanations advanced typically involve presumed tidal dissipation and/or converted incident stellar radiation. The present, brief communication suggests a novel interfacial nuclear fission-fusion source of internal heat production for hot Jupiters that has been overlooked by theoreticians and which has potentially general applicability.

J. Marvin Herndon

2006-12-20

269

Localization and expression of transformed DNA sequences within heat shock puffs of Drosophila melanogaster  

Microsoft Academic Search

In situ hybridization at high resolution with biotin-labeled DNA was used to locate specific transcriptional units within the chromosomal puffs of normal heat shock loci and of new heat shock loci generated by transformation. This method resolves copies of thehsp70 gene that are separated by 40 kb within the 87C heat shock locus. In the case of two new puff

Jeffrey A. Simon; Claudia A. Sutton; John T. Lis

1985-01-01

270

New Topographic Products and Rover Localization Results for the 2003 Mars Exploration Rover Mission  

Microsoft Academic Search

For over two years of MER surface operations, topographic maps, rover traverse maps, and updated rover locations of Spirit and Opportunity have supported tactical and strategic mission operations. Here we present the recent topographic products and the latest localization results.

R. Li; R. E. Arvidson; S. Agarwal; J. F. Bell III; E. Brodyagina; L. S. Crumpler; D. J. Des Marais; K. di; M. Golombek; J. Grant; R. L. Kirk; M. Maimone; L. H. Matthies; M. Malin; T. Parker; L. A. Soderblom; S. W. Squyres; J. Wang; L. Yan

2006-01-01

271

Consistent pattern of local adaptation during an experimental heat wave in a pipefish-trematode host-parasite system.  

PubMed

Extreme climate events such as heat waves are expected to increase in frequency under global change. As one indirect effect, they can alter magnitude and direction of species interactions, for example those between hosts and parasites. We simulated a summer heat wave to investigate how a changing environment affects the interaction between the broad-nosed pipefish (Syngnathus typhle) as a host and its digenean trematode parasite (Cryptocotyle lingua). In a fully reciprocal laboratory infection experiment, pipefish from three different coastal locations were exposed to sympatric and allopatric trematode cercariae. In order to examine whether an extreme climatic event disrupts patterns of locally adapted host-parasite combinations we measured the parasite's transmission success as well as the host's adaptive and innate immune defence under control and heat wave conditions. Independent of temperature, sympatric cercariae were always more successful than allopatric ones, indicating that parasites are locally adapted to their hosts. Hosts suffered from heat stress as suggested by fewer cells of the adaptive immune system (lymphocytes) compared to the same groups that were kept at 18°C. However, the proportion of the innate immune cells (monocytes) was higher in the 18°C water. Contrary to our expectations, no interaction between host immune defence, parasite infectivity and temperature stress were found, nor did the pattern of local adaptation change due to increased water temperature. Thus, in this host-parasite interaction, the sympatric parasite keeps ahead of the coevolutionary dynamics across sites, even under increasing temperatures as expected under marine global warming. PMID:22303448

Landis, Susanne H; Kalbe, Martin; Reusch, Thorsten B H; Roth, Olivia

2012-01-01

272

Local technological capability and productivity spillovers from FDI in the Uruguayan manufacturing sector  

Microsoft Academic Search

This article examines intra?industry spillovers from FDI in Uruguayan manufacturing plants in 1988, to determine whether differences in the technology gap between locally?owned plants and foreign affiliates have any impact on the relation between local productivity and foreign presence. We find a positive and statistically significant spillover effect only in a sub?sample of locally?owned plants with moderate technology gaps vis?à?vis

Ari Kokko; Ruben Tansini; Mario C. Zejan

1996-01-01

273

Immunocytochemical Localization of the Cystic Fibrosis Gene Product CFTR  

Microsoft Academic Search

Antisera against two peptides, corresponding to different domains of the cystic fibrosis gene product CFTR, have been raised and extensively characterized. Both antisera recognize CFTR as a 165-kDa polypeptide in Western analysis of cells transfected with CFTR cDNA as well as in epithelial cell lines. The cell and tissue distribution of CFTR has been studied by immunocytochemistry. CFTR is abundant

Isabelle Crawford; Peter C. Maloney; Pamela L. Zeitlin; William B. Guggino; Stephen C. Hyde; Helen Turley; Kevin C. Gatter; Ann Harris; Christopher F. Higgins

1991-01-01

274

Production of 5'-phosphodiesterase by Catharanthus roseus cells promoted by heat-degraded products generated from uronic acid.  

PubMed

Polyalginate was autoclaved at 121 degrees C for 20 min and its molecular weight distribution was analyzed. The autoclaved alginate yielded alginate polymer, oligomer and heat degraded products (HDPs). Each of the separated substances promoted 5'-phosphodiesterase (5'-PDase) production in suspension culture of Catharanthus roseus cells. HDPs could also be generated from other uronic acids (galacturonic acid and glucuronic acid) by autoclave treatment. The most effective substance in the HDPs was isolated and characterized as trans-4,5-dihydroxy-2-cyclopenten-1-one (DHCP). The optimal conditions for DHCP production were also established (autoclaving 1 mg/ml monogalacturonic acid [pH 2] at 121 degrees C for 2 h). A combination of oligo-alginate (below 4 kDa) and HDPs significantly promoted the production of 5'-PDase in C. roseus. Based on the above results, a novel alginate complex that gave a 44-fold increase in 5'-PDase production by C. roseus was developed. PMID:16233285

Akimoto-Tomiyama, Chiharu; Aoyagi, Hideki; Ozawa, Tetsuo; Tanaka, Hideo

2002-01-01

275

Heat-inducible production of beta-glucuronidase in tobacco hairy root cultures.  

PubMed

The production of beta-glucuronidase (GUS) driven by the Arabidopsis small heat shock protein 18.2 promoter in liquid cultures of transgenic tobacco (Nicotiana tabacum) hairy roots is reported. Clone GD-3, showing high GUS heat induction and a moderate growth rate, was selected from 436 clones for study. Treatment of GD-3 with heat shock at 36-42 degrees C for 2 h then recovery at 27 degrees C resulted in an increase in GUS specific activity, while higher heat-shock temperatures led to a decline. These results were in accordance with the change in esterase activity, a measure of tissue viability. Using 2 h of 42 degrees C heat shock and a recovery phase at 27 degrees C, GUS specific activity increased rapidly and reached a maximum of 267.6 nmol 4-methylumbelliferyl beta-D-glucuronic acid (MU) min-1 mg-1 protein at 24 h of recovery. When tissues were continuously heated at 42 degrees C and tested without a recovery period, GUS mRNA was detectable at 2 h and peaked at 5 h, but GUS activity was not seen until 10 h and did not peak until 28 h; in addition, the maximum activity was lower than that seen after heat shock for only 30 min or 2 h, followed by recovery. This shows that recovery at normal temperature is crucial for the heat-inducible heterogeneous expression system of transgenic hairy roots. Multiple heat-shock treatments showed that this system was heat reinducible, although a gradual decline in GUS specific activity was seen in the second and third cycles. PMID:16957892

Lee, Kung-Ta; Chen, Shih-Cheng; Chiang, Bor-Luen; Yamakawa, Takashi

2007-01-01

276

Investigation of Local Heat-transfer and Pressure Drag Characteristics of a Yawed Circular Cylinder at Supersonic Speeds  

NASA Technical Reports Server (NTRS)

Local heat-transfer coefficients, temperature recovery factors, and pressure distributions were measured on the front side of a circular cylinder at a nominal Mach number of 3.9 over a range of free-stream Reynolds numbers from 2.1 x 10 to the 3rd power to 6.7 x 10 to the 3rd power and yaw angles from zero degrees to 44 degrees. Yawing the cylinder reduced the heat-transfer coefficients and the pressure drag coefficients. The amount of reduction may be predicted by a theory presented herein.

Goodwin, Glen; Creager, Marcus O; Winkler, Ernest L

1956-01-01

277

Heat and moisture production of growing-finishing gilts as affected by environmental temperature  

Technology Transfer Automated Retrieval System (TEKTRAN)

Heat and moisture production (HMP) values are used to size ventilation fans in animal housing. The HMP values that are currently published in the ASABE (American Society of Agricultural and Biological Engineers) standards were from data collected in the early 1950. This study is one of a series of...

278

Personal factors in thermal comfort assessment: clothing properties and metabolic heat production  

Microsoft Academic Search

In the assessment of thermal comfort in buildings, the use of the Predicted Mean Vote (PMV) model is very popular. For this model, data on the climate, on clothing and on metabolic heat production are required. This paper discusses the representation and measurement of clothing parameters and metabolic rate in the PMV context. Several problems are identified and for some

George Havenith; Ingvar Holmér; Ken Parsons

2002-01-01

279

Measurements of bremsstrahlung production and x-ray cryostat heating in VENUS  

Microsoft Academic Search

The VENUS superconducting electron cyclotron resonance (ECR) ion source is designed to operate at 28 GHz with up to 10 kW of rf power. Most of this power is absorbed by the plasma electrons and then dumped onto the plasma chamber wall. The distribution of heating and bremsstrahlung production is highly nonuniform and reflects the geometry of the magnetic confinement

C. Lyneis; D. Leitner; D. Todd; S. Virostek; T. Loew; A. Heinen; O. Tarvainen

2006-01-01

280

Regulation of Heat Production in the Inflorescences of an Arum Lily by Endogenous Salicylic Acid  

Microsoft Academic Search

We have recently purified calorigen, the natural trigger for heat production in the inflorescences of Sauromatum guttatum Schott (voodoo lily), a thermogenic plant, and identified it as salicylic acid. Since then an analytical assay was developed that allows the quantitation of salicylic acid in plant tissues. This assay was used to demonstrate that on the day preceding the day of

Ilya Raskin; Ivan M. Turner; Wayne R. Melander

1989-01-01

281

Volatile production during preignition heating. Final technical report, 15 September 1980-30 September 1982  

SciTech Connect

Pulverized coal particles, in a flowing inert nitrogen stream, have been heated by high power Carbon Dioxide Laser. The consequence of such an irradiation have proved to be both novel and surprising as a result of the rapid quenching of primary coal products. It ahs been found that the gas phase yield from such heating (typically, temperatures in excess of 1400 K at rates approx. 2 x 10/sup 5/ K/s) is very small (< 0.2 percent of coal carbon and hydrogen). Analysis of the solid residue has shown the presence of fine lacy particulate chains of material of 0.1 ..mu..m diameter, which appears to be soluble in tetrahydrofuran. The yields of solute were significantly much higher than for raw coals. Molecular weight of the solute material was high, being in the range of 600 to 3000. The above and substantiating evidence point to a new mechanism of high heating rate pyrolysis in which only tar-like materials are produced as primary products from the coal. It is hypothesized that gas phase products are primarily the result of secondary reactions of these primary products in the hot gas environments usually employed by other heating techniques.

Ballantyne, A.; Chou, H.; Flusberg, A.; Neoh, K.; Orozco, N.; Stickler, D.

1983-10-01

282

HEAT ISLAND OF SAN ANTONIO, TEXAS DETECTED BY MODIS/AQUA TEMPERATURE PRODUCT  

E-print Network

HEAT ISLAND OF SAN ANTONIO, TEXAS DETECTED BY MODIS/AQUA TEMPERATURE PRODUCT Hongjie Xie, Huade and Environment Science University of Texas at San Antonio San Antonio, TX 78249 Hongjie.Xie@utsa.edu Huade) phenomenon of San Antonio, Texas. Both day time (~1:30 pm, central standard time-CST) and night time (~1

Texas at San Antonio, University of

283

Heat unit availability for cotton production in the Ogallala Aquifer Region of the United States  

Technology Transfer Automated Retrieval System (TEKTRAN)

Expansion in cotton (Gossypium hirsutum L.) production in the Ogallala Aquifer Region can be tied to early maturing varieties, rising energy costs, and declining water levels in the Ogallala Aquifer. However, the feasibility of growing cotton considering the availability of heat units in this region...

284

TEMPERATURE-HUMIDITY INDICES AS INDICATORS OF MILK PRODUCTION LOSSES DUE TO HEAT STRESS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Meteorological data (1993 to 2004) from two public weather stations in Phoenix, AZ and Athens, GA were analyzed with test day milk yield data from herds nearby the weather stations to identify the most appropriate temperature humidity index (THI) to measure losses in milk production due to heat stre...

285

Production of Gluconic Acid by Some Local Fungi  

PubMed Central

Forty-one fungal species belonging to 15 fungal genera isolated from Egyptian soil and sugar cane waste samples were tested for their capacity of producing acidity and gluconic acid. For the tests, the fungi were grown on glucose substrate and culture filtrates were examined using paper chromatography analysis. Most of the tested fungi have a relative wide potentiality for total acid production in their filtrates. Nearly 51% of them showed their ability of producing gluconic acid. Aspergillus niger was distinguishable from other species by its capacity to produce substantial amounts of gluconic acid when it was cultivated on a selective medium. The optimized cultural conditions for gluconic acid yields were using submerged culture at 30? at initial pH 6.0 for 7 days of incubation. Among the various concentrations of substrate used, glucose (14%, w/v) was found to be the most suitable carbon source for maximal gluconic acid during fermentation. Maximum values of fungal biomass (10.02 g/l) and gluconic acid (58.46 g/l) were obtained when the fungus was grown with 1% peptone as sole nitrogen source. Influence of the concentration of some inorganic salts as well as the rate of aeration on the gluconic acid and biomass production is also described. PMID:24039465

Shindia, A. A.; El-Esawy, A. E.; Sheriff, Y. M. M. M.

2006-01-01

286

Local Heat Transfer and CHF for Subcooled Flow Boiling - Annual Report 1997  

SciTech Connect

The Thermal Science Research Center (TSRC) at Prairie View A&M University is involved in an international fusion reactor technology development program aimed at demonstrating the technical feasibility of magnetic fusion energy. This report highlights: (1) Recent accomplishments and pinpoints thermal hydraulic problem areas of immediate concern to the development of plasma-facing components, and (2) Next generation thermal hydraulic problems which must be addressed to insure safety and reliability in component operation. More specifically, the near-term thermal hydraulic problem entails: (1) generating an appropriate data base to insure the development of single-side heat flux correlations, and (2) evaluating previously developed single-side/uniform heated transformations and correlations to determine which can be used to relate the vast two-phase heat transfer and critical heat flux (CHF) technical literature for uniformly heated flow channels to single-side heated channels.

Dr. Ronald D. Boyd

2000-07-01

287

Competitiveness, Local Production Systems and Global Commodity Chains in the Music Industry: Entering the US Market  

Microsoft Academic Search

Power D. and Hallencreutz D. (2007) Competitiveness, local production systems and global commodity chains in the music industry: entering the US market, Regional Studies41, –. This paper traces the principal channels and barriers that determine the conditions of access for musical products entering the US music market. It is shown that music distribution channels and retail environments exist in a

Dominic Power; Daniel Hallencreutz

2007-01-01

288

Local Human Capital and Productivity: An Analysis for the Spanish Regions  

Microsoft Academic Search

Sanromá E. and Ramos R. (2007) Local human capital and productivity: an analysis for the Spanish regions, Regional Studies41, 349–359. This paper examines the relationship between the stock of human capital and productivity in the Spanish regions (NUTS III), and assesses whether the transmission channel involves external economies. The empirical evidence points to a positive relationship between the two variables,

Esteban Sanromá; Raúl Ramos

2007-01-01

289

Analysis of status quo, problems and potential about waste heat recovery of NSP cement production lines' exhaust gas  

Microsoft Academic Search

In this thesis, we have introduced the features of exhaust gas waste heat resources from both domestic and foreign NSP Cement Production Lines, summarized the status quo and problems about the technology of the exhaust gas heat recovery, and by calculating we analyzed the potential of the low temperature exhaust gas which has been used by the waste heat boilers.

Zhang He; Zhao Jinling; Zou Pinghua

2011-01-01

290

Localized heating of electrons in ionization zones: Going beyond the Penning-Thornton paradigm in magnetron sputtering  

SciTech Connect

The fundamental question of how energy is supplied to a magnetron discharge is commonly answered by the Penning-Thornton paradigm invoking secondary electrons. Huo et al. (Plasma Sources Sci. Technol. 22, 045005, (2013)) used a global discharge model to show that electron heating in the electric field of the magnetic presheath is dominant. In this contribution, this concept is applied locally taking into account the electric potential structure of ionization zones. Images of ionization zones can and should be interpreted as diagrams of the localization of electric potential and related electron energy, where certain collisions promote or dampen their formation.

Anders, Andre

2014-12-07

291

Effect of a rotor wake on the local heat transfer on the forward half of a circular cylinder  

NASA Technical Reports Server (NTRS)

Turbine rotor-stator wake dynamics was simulated by a spoked wheel rotating in annular flow, generating rotor wakes. Spanwise averaged circumferentially local heat transfer in the circular cylindrical leading edge region of a turbine airfoil was obtained. Reynolds numbers ranged from 35,000 to 175,000. Strouhal numbers ranged from 0.63 to 2.50. Wakes were generated by 2 sets of circular cylindrical bars, 1.59 and 3.18 mm in diameter. The rotor could be rotated either clockwise or counterclockwise. Grid turbulence was introduced upstream yielding freestream turbulence of 1.0 to 2.5% at the stator. Data represented an extensive body of local heat transfer coefficients, which can be used to model the leading edge region of a turbine airfoil. In the presence of rotor wakes, an asymmetry from the leeward to windward side was noted. Windward side levels were 30 to 40% higher than the corresponding leeward side.

Morehouse, K. A.; Simoneu, R. J.

1986-01-01

292

The importance of heat transports and local air-sea heat fluxes to the Barents Sea climate variability  

Microsoft Academic Search

The inflow of warm and saline Atlantic water into the Barents Sea is of significant importance to the regional ocean climate, as well as for the biomass production and fish distribution within the Barents Sea. Much effort has therefore been spent to explore the potential predictability of the system, either based on observations or using ocean- or coupled atmosphere-ocean models.

A. B. Sandø; Y. Gao; J. E. Ø. Nilsen; K. Lohmann

2009-01-01

293

Heat Conduction Analysis of 3-D Axisymmetric and Anisotropic FGM Bodies by Meshless Local Petrov–Galerkin Method  

Microsoft Academic Search

The meshless local Petrov–Galerkin method is used to analyze transient heat conduction in 3-D axisymmetric solids with continuously inhomogeneous and anisotropic material properties. A 3-D axisymmetric body is created by rotation of a cross section around an axis of symmetry. Axial symmetry of geometry and boundary conditions reduces the original 3-D boundary value problem into a 2-D problem. The cross

J. Sladek; V. Sladek; Ch. Hellmich; J. Eberhardsteiner

2007-01-01

294

Influence of U-bend heterogeneous effects on bubble dynamics and local flow boiling heat transfer in hairpin tubes  

Microsoft Academic Search

The present study describes a series of flow boiling experiments with R141b in coiled tubes conducted to investigate the local heat transfer enhancement mechanism of U-bends compared with bubbles growing in horizontal straight tubes. The study focuses on two-phase flows with boiling in U-bends of a vertical upward coiled tube of inner diameter 6 mm at mass fluxes of 120.94, 181.41

M. Meng; X. F. Peng

2011-01-01

295

Local and mean heat transfer at the leading edge of a turbine blade swept by a shock-free flow  

NASA Astrophysics Data System (ADS)

The hydrodynamics of flow in turbine blade cascades is studied with attention given to oscillation characteristics and local heat exchange in blade profiles with varying degrees of turbulence in the incoming flow. Two two-dimensional cascades consisting of five blades each with profiles of types T-54 and TS-1a are considered. A comparison is made between the starting unit characteristics for the GT-35 gas turbine plants at the Yakutsk, Moldavian, and Nevinomyssk Central Power Stations.

Titov, V. B.

1987-06-01

296

Experimental investigation into the effects of rotating and static bolts on both windage heating and local heat transfer coefficients in a rotor/stator cavity  

NASA Astrophysics Data System (ADS)

Experiments are carried out on the following combinations of bolts: single row rotating, single row static, double row rotating, and combined rotating and static. Different sizes of bolts were tested as well as variation in pitching and the effects of various bolt shields. The adiabatic wall temperature was measured locally at various positions on the rotor surface both between adjacent bolts and at different pitch circle diameters. In the course of the testing, a considerable reduction in windage due to the shape of the disc surface near the rim was measured. This study describes the experimental technique used and presents a selection of the windage and heat transfer results.

Millward, J. A.; Robinson, P. H.

1989-06-01

297

Evaluación de características productivas en cabritos Boer × local, Nubia × local y locales en el trópico seco de Guerrero, México Evaluation of productive traits in Boer × local, Nubian × local and local kids in the dry tropic of Guerrero, Mexico  

Microsoft Academic Search

By means of the GLM procedure of the SAS statistical package, the effects of the genetic groups (GG) Boer ? local (BL), Nubian ? local (NL) and local ? local (LL) kids, sex of kid (SK), type of birth (TB), age of dam (AD), season (SB) and year (YB) of birth, as well as genotype ? environment interactions on birth

Mayra I. Merlos-Brito; Rubén D. Martínez-Rojero; Ángel A. Mastache-Lagunas; Jaime Gallegos-Sánchez

298

Effects of heating rate on slow pyrolysis behavior, kinetic parameters and products properties of moso bamboo.  

PubMed

Effects of heating rate on slow pyrolysis behaviors, kinetic parameters, and products properties of moso bamboo were investigated in this study. Pyrolysis experiments were performed up to 700 °C at heating rates of 5, 10, 20, and 30 °C/min using thermogravimetric analysis (TGA) and a lab-scale fixed bed pyrolysis reactor. The results show that the onset and offset temperatures of the main devolatilization stage of thermogravimetry/derivative thermogravimetry (TG/DTG) curves obviously shift toward the high-temperature range, and the activation energy values increase with increasing heating rate. The heating rate has different effects on the pyrolysis products properties, including biochar (element content, proximate analysis, specific surface area, heating value), bio-oil (water content, chemical composition), and non-condensable gas. The solid yields from the fixed bed pyrolysis reactor are noticeably different from those of TGA mainly because the thermal hysteresis of the sample in the fixed bed pyrolysis reactor is more thorough. PMID:25063973

Chen, Dengyu; Zhou, Jianbin; Zhang, Qisheng

2014-10-01

299

Joule-Heated Molten Regolith Electrolysis Reactor Concepts for Oxygen and Metals Production on the Moon and Mars  

NASA Technical Reports Server (NTRS)

The maturation of Molten Regolith Electrolysis (MRE) as a viable technology for oxygen and metals production on explored planets relies on the realization of the self-heating mode for the reactor. Joule heat generated during regolith electrolysis creates thermal energy that should be able to maintain the molten phase (similar to electrolytic Hall-Heroult process for aluminum production). Self-heating via Joule heating offers many advantages: (1) The regolith itself is the crucible material, it protects the vessel walls (2) Simplifies the engineering of the reactor (3) Reduces power consumption (no external heating) (4) Extends the longevity of the reactor. Predictive modeling is a tool chosen to perform dimensional analysis of a self-heating reactor: (1) Multiphysics modeling (COMSOL) was selected for Joule heat generation and heat transfer (2) Objective is to identify critical dimensions for first reactor prototype.

Sibille, Laurent; Dominques, Jesus A.

2012-01-01

300

Identification of potential local isolated for biosurfactant production  

NASA Astrophysics Data System (ADS)

Biosurfactant are amphiphilic molecule that have received increasing attention in recent years because of their role in the growth of microorganisms on water-insoluble hydrophobic materials such as hydrocarbons as well as their commercial potential in the cosmetics, food, oil recovery and agricultural industries. In this study a potential biosurfactant producing strain was isolated from several soil samples of Terengganu oil refinery, Malaysia and selected during preliminary screening using hemolytic activity, oil spreading and drop collapsed technique. Isolates with at least more than one positive response to these three methods were subjected to complementary screening by measuring surface tension reduction as well as emulsification capacity. The biosurfactant produced by isolated 5M was able to reduced surface tension of culture medium from 60 mN/m to30mN/m. The biochemical and morphological characterization, 16SrRNA gene sequencing showed that the isolated 5M belongs to bacillus groups. The maximum production of biosurfactant by Bacillus 5M was observed after 48 h of incubation.

Shafiei, Zahra; Yusoff, Wan Mohtar Wan; Hamid, Aidil Abdul; Moazami, Nasrin; Hamzah, Ainon; Fooladi, Taybeh

2013-11-01

301

Local heat transfer and film effectiveness of a film cooled gas turbine blade tip  

E-print Network

. 0x10, M = 0. 75 and D/W = 0. 1. 39 23 Heat Transfer Distribution for ot = 45', Re = 5. 0x10, M = 1. 0 and D/W = 0. 1. 40 24 Heat Transfer Distribution for rr = 45', Re = 5. 0x10', M = 2. 0 and D/W = O. l. 41 25 Heat Transfer Distribution for u.../Nu?r 0 267 345 430 600 Flow Direction Figure 25 Heat Transfer Distribution for et=45', Re = 1. 0x10, M = 0. 75 and D/W = 0. 1 43 Nu/Nu?t 0 2. 66 3. 18 4. 21 6. 92 R Figure 26 Heat Transfer Distribution for et=45', Re = 1. 0x10, M = 1. 0 and D/W = 0...

Adewusi, Adedapo Oluyomi

1999-01-01

302

Composite heat-insulating material and process for the production thereof  

SciTech Connect

A composite heat-insulating material and a process for the production thereof are described. This material is of the structure that an olefin- or styrene-based resin sheet and a urethane foam material are laminated on each other with an adhesive containing: (A) 20 to 100% by weight of a water-soluble polyamine compound selected from the group consisting of polyethyleneimine, poly(ethyleneimine-urea), and a polyaminepolyamide/ethyleneimine adduct, and (B) 80 to 0% by weight of a nitrogen atom-containing cationic or amphoteric polymer. This composite heat-insulating material is very suitable for use as a lining material for a refrigerator, for example.

Yazaki, T.; Hattori, K.; Hattori, S.; Hayama, K.; Itoh, I.

1985-02-19

303

Effect of temperature and heating rate on apparent lethal concentrations of pyrolysis products  

NASA Technical Reports Server (NTRS)

The apparent lethal concentrations for 50 percent of the test animals of the pyrolysis products from twelve polymeric materials were studied as a function of temperature and heating rate. The materials were polyethylene, nylon 6, ABS, polycarbonate, polyether sulfone, polyaryl sulfone, wool fabric, aromatic polyamide fabric, polychloroprene foam, polyvinyl fluoride film, Douglas fir, and red oak. The apparent lethal concentration values of most materials vary significantly with temperature and heating rate. The apparent lethal concentration values, based on weight of sample charged, appears to effectively integrate the thermophysical, thermochemical, and physiological responses from a known quantity of material under specified imposed conditions.

Hilado, C. J.; Solis, A. N.; Marcussen, W. H.; Furst, A.

1976-01-01

304

Heat-resistance of Hamigera avellanea and Thermoascus crustaceus isolated from pasteurized acid products.  

PubMed

Products containing sugar or fruit derivatives are usually subjected to a pasteurization process that can anyway be ineffective to kill ascospores from heat-resistant molds. Although the most occurring and economically relevant heat-resistant species belong to Byssochlamys, Neosartorya, Talaromyces, and Eupenicillium genera, an increasing number of uncommon heat-resistant isolates have been recently detected as spoiling microorganisms in such products. Since Hamigera spp. and Thermoascus spp. were those more frequently isolated at SSICA, heat resistance of Hamigera avellanea and Thermoascus crustaceus strains from pasteurized acid products was studied in apple juice, in blueberry and grape juice and in a buffered glucose solution. Data obtained from thermal death curves and statistical elaboration of raw data showed that D values of H. avellanea may vary between 11.11 and 66.67 min at 87°C, between 4.67 and 13.51 at 90°C, and between 0.43 and 1.52 min at 95°C. Similarly, D values of T. crustaceus may vary between 18.52 and 90.91 min at 90°C, between 2.79 and 19.23 at 93°C, and between 1.11 and 2.53 min at 95°C. For both strains studied, the z-values calculated from the decimal reduction time curves did not prove to be significantly influenced by the heating medium, that being 4.35°C, 5.39°C or 5.27°C for H. avellanea and 4.42°C, 3.69°C or 3.37°C for T. crustaceus, respectively in apple juice, in blueberry and grape juice or in the buffered glucose solution. Considering the pasteurization treatments industrially applied to fruit-based foods, the variation of thermal parameters does not seem to be a possible way to avoid product spoilage by these two species and only good practices applied to reduce the original load of heat-resistant fungi can help producers to prevent losses in contaminated finished products, as usually happens for other heat resistant molds. PMID:24239977

Scaramuzza, Nicoletta; Berni, Elettra

2014-01-01

305

Locally Indistinguishable Subspaces Spanned by Three-Qubit Unextendible Product Bases  

E-print Network

We study the local distinguishability of general multi-qubit states and show that local projective measurements and classical communication are as powerful as the most general local measurements and classical communication. Remarkably, this indicates that the local distinguishability of multi-qubit states can be decided efficiently. Another useful consequence is that a set of orthogonal $n$-qubit states is locally distinguishable only if the summation of their orthogonal Schmidt numbers is less than the total dimension $2^n$. When $n=2$ such a condition is also sufficient. Employing these results, we show that any orthonormal basis of a subspace spanned by arbitrary three-qubit orthogonal unextendible product bases (UPB) cannot be exactly distinguishable by local operations and classical communication. This not only reveals another intrinsic property of three-qubit orthogonal UPB, but also provides a class of locally indistinguishable subspaces with dimension 4. We also explicitly construct locally indistinguishable subspaces with dimensions 3 and 5, respectively. In particular, 3 is the minimal possible dimension of locally indistinguishable subspaces. Combining with the previous results, we conclude that any positive integer between 3 and 7 is the possible dimension of some three-qubit locally indistinguishable subspace.

Runyao Duan; Yu Xin; Mingsheng Ying

2008-09-25

306

Local dependence of ion temperature gradient on magnetic configuration, rotational shear and turbulent heat flux in MAST  

NASA Astrophysics Data System (ADS)

Experimental data from the Mega Amp Spherical Tokamak (MAST) is used to show that the inverse gradient scale length of the ion temperature R/L_{T_\\rmi} has its strongest local correlation with the rotational shear and the pitch angle of the magnetic field. Furthermore, R/L_{T_\\rmi} is found to be inversely correlated with the gyro-Bohm-normalized local turbulent heat flux estimated from the density fluctuation level measured using a 2D beam emission spectroscopy diagnostic. These results can be explained in terms of the conjecture that the turbulent system adjusts to keep R/L_{T_\\rmi} close to a certain critical value (marginal for the excitation of turbulence) determined by local equilibrium parameters (although not necessarily by linear stability).

Ghim, Y.-c.; Field, A. R.; Schekochihin, A. A.; Highcock, E. G.; Michael, C.; the MAST Team

2014-04-01

307

Experimental investigation of local heat transfer in the packing with triangular channels  

NASA Astrophysics Data System (ADS)

Results of experimental studies on temperature distribution over the surface of a complex-shape heat exchanger like “Frenkel packing” are presented. Measurements were carried out with the airflow between two corrugated sheets with triangular crimps directed at 90° relative to each other. Microthermocouples glued on the outer surface of the heater were used for measurements. The effect of contact points, Reynolds number, and gap between corrugated sheets on temperature distribution over the heat exchanger surface is analysed under the turbulent mode of airflow. The main attention is paid to temperature distribution over the heating surface in an elementary cell. According to measurements performed, there is insignificant effect of contact points and gap on the type of temperature distribution over the perimeter of heated cell.

Perepelitsa, B. V.

2006-12-01

308

Control of Byssochlamys and Related Heat-resistant Fungi in Grape Products  

PubMed Central

Heat-resistant strains of Byssochlamys fulva, B. nivea, and other heat-resistant fungi were isolated from vineyard soil, grapes, grape-processing lines, and waste pomace. They are known to remain in grape juice occasionally and to grow in grape juice products. Ascospores of these fungi have a D value (decimal reduction time) of about 10 min at 190 F (88 C), but in the presence of 90 ?liters of SO2 per liter (normally added to the juice) the D value was cut in half. Filtration through a commercial diatomaceous filter aid (also a common processing step) entrapped all but about 0.001% of experimentally added spores. Thus, heat in the presence of SO2 and filtration together can reduce the population of these spores by several orders of magnitude. Growth was also prevented by benzoate or sorbate in low concentrations. Oxygen must be reduced to extremely low levels before lack of oxygen limits growth. Images PMID:16349856

King, A. Douglas; Michener, H. David; Ito, Keith A.

1969-01-01

309

Carbon dioxide local heat transfer coefficients during flow boiling in a horizontal circular smooth tube  

Microsoft Academic Search

Carbon dioxide is gaining renewed interest as an environmentally safe refrigerant. In order to improve the energy efficiency of R744 systems, an accurate knowledge of heat transfer coefficients is fundamental.In this paper experimental heat transfer coefficients during flow boiling of R744 in a smooth, horizontal, circular, 6.00mm inner diameter tube are presented. We obtained 217 experimental points in 18 operating

R. Mastrullo; A. W. Mauro; A. Rosato; G. P. Vanoli

2009-01-01

310

Local Melting and Formation Steps of Solder Bumps via Induction Heating Reflow  

Microsoft Academic Search

This work focuses on the nonuniform melting process and its theoretical explanation. After induction heating for 0.8 s, 1.0 s, 1.4 s and 2.0 s, different welding state can be obtained, which gives a proof of the melting process. The experiment results demonstrate that the skin effect of induction heating forms the great temperature gradient in the solder bump. The

Hongbo Xu; Mingyu Li; Gang Cheng; Jongmyung Kim; Daewon Kim

2007-01-01

311

Signatures of Local and Coronal Ion Heating Embedded in Solar Wind Observations  

NASA Astrophysics Data System (ADS)

Observations of the solar wind are a uniquely powerful tool for testing theories of coronal heating because we can directly observe particles and their interactions with electromagnetic structures and fluctuations. However, there are challenges. A mechanism that works well in the solar wind may not be applicable to regions in the corona where the plasma beta is much smaller; a non-thermal aspect of the solar wind could reflect an ongoing process or be a relic signature of events deep in the corona. The purpose of this presentation is to demonstrate how large solar wind datasets may be used to determine how heating mechanisms depend on ambient plasma conditions, such as plasma beta, and to illustrate a new technique for unfolding the overall heating history of solar wind from the corona into interplanetary space. We focus on the question of the relative heating of ionized hydrogen and helium in the solar wind as a function of plasma beta, differential ion flow, and plasma beta. We demonstrate that the preferential heating of helium is regulated by both differential flow and plasma beta, and compare our observations with several theories of ion heating. In particular, we propose an extension of the resonance condition for parallel-propagating ion cyclotron waves for finite temperatures, and show that the resulting predictions for the beta-dependence of relative ion heating compare favorably with our observations. Finally, we show how the dependence of ion properties on the Coulomb collisional age of the plasma can be inverted to estimate the relative strength of this heating mechanism as a function of distance from the Sun. Our predictions for the inner heliosphere will be tested directly by the upcoming Solar Probe Plus and Solar Orbiter missions.

Kasper, J. C.; Stevens, M. L.; Maruca, B. A.; Zaslavsky, A.

2012-12-01

312

Development of Naphthalene PLIF for Visualizing Ablation Products From a Space Capsule Heat Shield  

NASA Technical Reports Server (NTRS)

The Orion Multi-Purpose Crew Vehicle (MPCV) will use an ablative heat shield. To better design this heat shield and others that will undergo planetary entry, an improved understanding of the ablation process would be beneficial. Here, a technique developed at The University of Texas at Austin that uses planar laser-induced fluorescence (PLIF) of a low-temperature sublimating ablator (naphthalene) to enable visualization of the ablation products in a hypersonic flow is applied. Although high-temperature ablation is difficult and expensive to recreate in a laboratory environment, low-temperature sublimation creates a limited physics problem that can be used to explore ablation-product transport in a hypersonic flow-field. In the current work, a subscale capsule reentry vehicle model with a solid naphthalene heat shield has been tested in a Mach 5 wind tunnel. The PLIF technique provides images of the spatial distribution of sublimated naphthalene in the heat-shield boundary layer, separated shear layer, and backshell recirculation region. Visualizations of the capsule shear layer using both naphthalene PLIF and Schlieren imaging compared favorably. PLIF images have shown high concentrations of naphthalene in the capsule separated flow region, intermittent turbulent structures on the heat shield surface, and interesting details of the capsule shear layer structure. It was shown that, in general, the capsule shear layer appears to be more unsteady at lower angels of attack. The PLIF images demonstrated that during a wind tunnel run, as the model heated up, the rate of naphthalene ablation increased, since the PLIF signal increased steadily over the course of a run. Additionally, the shear layer became increasingly unsteady over the course of a wind tunnel run, likely because of increased surface roughness but also possibly because of the increased blowing. Regions with a relatively low concentration of naphthalene were also identified in the capsule backshell recirculation region and are most likely the result of cross-flow-induced vortices on the capsule afterbody.

Combs, C. S.; Clemens, N. T.; Danehy, P. M.

2014-01-01

313

Local heat treatment of high strength steels with zoom-optics and 10kW-diode laser  

NASA Astrophysics Data System (ADS)

High strength steels enable new solutions for weight optimized car bodies without sacrificing crash safety. However, cold forming of these steels is limited due to the need of high press capacity, increased tool wear, and limitations in possible geometries. One can compensate for these drawbacks by local heat treatment of the blanks. In high-deformation areas the strength of the material is reduced and the plasticity is increased by diode laser irradiation. Local heat treatment with diode laser radiation could also yield key benefits for the applicability of press hardened parts. High strength is not desired all over the part. Joint areas or deformation zones for requested crash properties require locally reduced strength. In the research project "LOKWAB" funded by the German Federal Ministry of Education and Research (BMBF), heat treatment of high strength steels was investigated in cooperation with Audi, BMW, Daimler, ThyssenKrupp, Fraunhofer- ILT, -IWU and others. A diode laser with an output power of 10 kW was set up to achieve acceptable process speed. Furthermore a homogenizing zoom-optics was developed, providing a rectangular focus with homogeneous power density. The spot size in x- and y-direction can be changed independently during operation. With pyrometer controlled laser power the surface temperature is kept constant, thus the laser treated zone can be flexibly adapted to the needs. Deep-drawing experiments show significant improvement in formability. With this technique, parts can be manufactured, which can conventionally only be made of steel with lower strength. Locally reduced strength of press hardened serial parts was demonstrated.

Baumann, Markus; Krause, Volker; Bergweiler, Georg; Flaischerowitz, Martin; Banik, Janko

2012-03-01

314

Effect of Discrete Fracture Network Characteristics on the Sustainability of Heat Production in Enhanced Geothermal Reservoirs  

NASA Astrophysics Data System (ADS)

Viability of an enhanced or engineered geothermal reservoir is determined by the rate of produced fluid at production wells and the rate of temperature drawdown in the reservoir as well as that of the produced fluid. Meeting required targets demands sufficient permeability and flow circulation in a relatively large volume of rock mass. In-situ conditions such overall permeability of the bedrock formation, magnitude and orientation of stresses, and the characteristics of the existing Discrete Fracture Network (DFN) greatly affect sustainable heat production. Because much of the EGS resources are in formations with low permeability, different stimulation techniques are required prior to the production phase to enhance fluid circulation. Shear stimulation or hydro-shearing is the method of injecting a fluid into the reservoir with the aim of increasing the fluid pressure in the naturally fractured rock and inducing shear failure or slip events. This mechanism can enhance the system's permeability through permanent dilatational opening of the sheared fractures. Using a computational modeling approach, the correlation between heat production and DFN statistical characteristics, namely the fracture length distribution, fracture orientation, and also fracture density is studied in this paper. Numerical analyses were completed using two-dimensional distinct element code UDEC (Itasca, 2011), which represents rock masses as an assembly of interacting blocks separated by fractures. UDEC allows for simulation of fracture propagation along the predefined planes only (i.e., the trajectory of the hydraulic fracture is not part of the solution of the problem). Thus, the hydraulic fracture is assumed to be planar, aligned with the direction of the major principal stress. The pre-existing fractures were represented explicitly. They are discontinuities which deform elastically, but also can open and slip (Coulomb slip law) as a function of pressure and total stress changes. The fluid injection into the reservoir during stimulation phase was simulated using a fully coupled hydro-mechanical model. The heat production phase was simulated using a coupled thermo-hydro-mechanical model. In these simulations, both advective heat transfer by fluid flow and the conductive heat transfer within the rock blocks were modeled. The effect of temperature change on stresses and fracture aperture, and thus flow rates was considered. The response of formations with different DFN characteristics are analyzed by evaluating the production rate, produced power, and total energy extracted from the system over a period of five years. By simulating a full cycle of stimulation and production, the numerical modeling approach represents a realistic estimate of evolving permeability and evaluates how stimulation can be beneficial to the production phase. It is believed that these numerical sensitivity studies can provide valuable insight in evaluation of the potential of success of an EGS project, and can be used to better design the operational parameters in order to optimize heat production. Keywords: Numerical modeling, rock mechanics, discrete fracture network, stimulation, engineered geothermal reservoirs, heat production

Riahi, A.; Damjanac, B.

2013-12-01

315

Heat production rate from radioactive elements in igneous and metamorphic rocks in Eastern Desert, Egypt.  

PubMed

Radioactive heat-production data of Igneous and Metamorphic outcrops in the Eastern Desert are presented. Samples were analysed using a low level gamma-ray spectrometer (HPGe) in the laboratory. A total of 205 rock samples were investigated, covering all major rock types of the area. The heat-production rate of igneous rocks ranges from 0.11 (basalt) to 9.53 microWm(-3) (granite). In metamorphic rocks it varies from 0.28 (serpentinite ) to 0.91 microWm(-3) (metagabbro). The contribution due to U is about 51%, as that from Th is 31% and 18% from K. The corresponding values in igneous rocks are 76%, 19% and 5%, respectively. The calculated values showed good agreement with global values except in some areas containing granites. PMID:16120480

Abbady, Adel G E; El-Arabi, A M; Abbady, A

2006-01-01

316

Thermal imaging of receptor-activated heat production in single cells.  

PubMed Central

Changes in enthalpy (i.e., heat content) occur during the diverse intracellular chemical and biophysical interactions that take place in the life cycle of biological cells. Such changes have previously been measured for cell suspensions or cell-free biochemical extracts by using microcalorimetry, thermocouples, or pyroelectric films, all of which afford minimal spatial or temporal resolution. Here we present a novel thermal imaging method that combines both diffraction-limited spatial (approximately 300 nm) and sampling-rate-limited time resolution, using the temperature-dependent phosphorescence intensity of the rare earth chelate Eu-TTA (europium (III) thenoyltrifluoro-acetonate). With this thermosensitive dye, we imaged intracellular heat waves evoked in Chinese hamster ovary cells after activation of the metabotropic m1-muscarinic receptor. Fast application of acetylcholine onto the cells evoked a biphasic heat wave that was blocked by atropine, and after a brief delay was followed by a calcium wave. Atropine applied by itself produced a monophasic heat wave in the cells, suggesting that its interactions with the receptor activate some intracellular metabolic pathways. The thermal imaging technique introduced here should provide new insights into cellular functions by resolving the location, kinetics, and quantity of intracellular heat production. PMID:9449312

Zohar, O; Ikeda, M; Shinagawa, H; Inoue, H; Nakamura, H; Elbaum, D; Alkon, D L; Yoshioka, T

1998-01-01

317

Locally indistinguishable subspaces spanned by three-qubit unextendible product bases  

SciTech Connect

We study the local distinguishability of general multiqubit states and show that local projective measurements and classical communication are as powerful as the most general local measurements and classical communication. Remarkably, this indicates that the local distinguishability of multiqubit states can be decided efficiently. Another useful consequence is that a set of orthogonal n-qubit states is locally distinguishable only if the summation of their orthogonal Schmidt numbers is less than the total dimension 2{sup n}. Employing these results, we show that any orthonormal basis of a subspace spanned by arbitrary three-qubit orthogonal unextendible product bases (UPB) cannot be exactly distinguishable by local operations and classical communication. This not only reveals another intrinsic property of three-qubit orthogonal UPB but also provides a class of locally indistinguishable subspaces with dimension 4. We also explicitly construct locally indistinguishable subspaces with dimensions 3 and 5, respectively. Similar to the bipartite case, these results on multipartite locally indistinguishable subspaces can be used to estimate the one-shot environment-assisted classical capacity of a class of quantum broadcast channels.

Duan Runyao; Ying Mingsheng [Centre for Quantum Computation and Intelligent Systems (QCIS), Faculty of Engineering and Information Technology, University of Technology, Sydney, New South Wales 2007 (Australia); State Key Laboratory of Intelligent Technology and Systems, Tsinghua National Laboratory for Information Science and Technology, Department of Computer Science and Technology, Tsinghua University, Beijing 100084 (China); Xin Yu [Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Department of Physics, Tsinghua University, Beijing 100084 (China)

2010-03-15

318

Protein Interaction of Retinoblastoma Gene Product pRbllO with Mr 73,000 Heat Shock Cognate Protein1  

Microsoft Academic Search

Both the tumor suppressor gene products, the retinoblastoma sensitiv ity gene product pRbllO and p53, are found in oligomer complexes with the oncogene products of the DNA tumor viruses. It has been demon strated that p53 binds to the A\\/, 70.000 heat shock protein family. How ever, the protein association of pRbllO with the A\\/, 70,000 heat shock protein family

Takehito Nihei; Shuji Takahashi; Satoru Sagae; Noriyuki Sato; Kokichi Kikuchi

319

Measurement of local strain and heat propagation during high-temperature testing in a split-Hopkinson tension bar system  

NASA Astrophysics Data System (ADS)

Aluminium alloys are commonly used by the industry due to their good mechanical properties and their relatively low density. An accurate prediction of the behaviour of aluminium alloys under a wide range of temperatures and strain rates is important in numerical simulations of forming processes or applications involving adiabatic heating like penetration and crash situations. Several tests are needed at low, medium and high strain rates to study this behaviour. This paper will focus on the high strain rate test rig, which is a split- Hopkinson tension bar system (SHTB), the acquisition system for strain measurements, and a thermal analysis of the bars due to heating of the sample. A new way of doing local measurements with a high-speed camera will be presented. The thermal boundary conditions of the tests have been measured and simulated, and the results indicate that the stress wave propagation in the bars is not significantly affected by a local heating of the part of the bars which is closest to the sample.

Vilamosa, V.; Clausen, A. H.; Hopperstad, O. S.; Børvik, T.; Skjervold, S.

2012-08-01

320

Laser Doppler flowmetry: multifractal spectra of signals recorded in hand of young healthy subjects before and after local heating  

E-print Network

Laser Doppler flowmetry: multifractal spectra of signals recorded in hand of young healthy subjects-- Laser Doppler flowmetry (LDF) signals give a peripheral view of the cardiovascular system. We herein, leading to an increase of the local skin blood flow via, among others, the production of nitric oxide. LDF

Chapeau-Blondeau, François

321

Radioactive heat production in rocks and its relation to other petrophysical parameters  

Microsoft Academic Search

Radioactive heat productionA is a scalar and isotropic petrophysical property independent of in situ temperature and pressure. Its value is usually expressed in HGU units (1 HGU=10-13 cal\\/cm3 sec) and depends on the amounts of uranium, thorium and potassium.A varies with rock type over several orders of magnitude and reflects the geochemical conditions during rock formation (magmatic differentiation, sedimentation or

Ladislaus Rybach

1976-01-01

322

Studies of the use of high-temperature nuclear heat from an HTGR for hydrogen production  

NASA Technical Reports Server (NTRS)

The results of a study which surveyed various methods of hydrogen production using nuclear and fossil energy are presented. A description of these methods is provided, and efficiencies are calculated for each case. The process designs of systems that utilize the heat from a general atomic high temperature gas cooled reactor with a steam methane reformer and feed the reformer with substitute natural gas manufactured from coal, using reforming temperatures, are presented. The capital costs for these systems and the resultant hydrogen production price for these cases are discussed along with a research and development program.

Peterman, D. D.; Fontaine, R. W.; Quade, R. N.; Halvers, L. J.; Jahromi, A. M.

1975-01-01

323

Oral administration of ?-aminobutyric acid affects heat production in a hot environment in resting humans  

PubMed Central

Background Central administration of ?-amino butyric acid (GABA) induces lower body temperature in animals in hot ambient air. However, it is still unknown whether oral GABA administration affects temperature regulation at rest in a hot environment in humans. Therefore, in the present study, we specifically hypothesized that systemic administration of GABA in humans would induce hypothermia in a hot environment and that this response would be observed in association with decreased heat production. Methods Eight male participants drank a 200-ml sports drink with 1 g of GABA (trial G) or without GABA (trial C), then rested for 30 minutes in a sitting position in a hot environment (ambient air temperature 33°C, relative humidity 50%). Results We found that changes in esophageal temperature from before drinking the sports drink were lower in trial G than in trial C (-0.046 ± 0.079°C vs 0.001 ± 0.063°C; P < 0.05), with lower heat production calculated by oxygen consumption (41 ± 5 W/m2 vs 47 ± 8 W/m2; P < 0.05). Conclusions In this study, we have demonstrated that a single oral administration of GABA induced a larger decrease in body core temperature compared to a control condition during rest in a hot environment and that this response was concomitant with a decrease in total heat production. PMID:22738209

2012-01-01

324

Technological Alternatives or Use of Wood Fuel in Combined Heat and Power Production  

NASA Astrophysics Data System (ADS)

Abstract Latvia aims for 40% share of renewable energy in the total final energy use. Latvia has large resources of biomass and developed district heating systems. Therefore, use of biomass for heat and power production is an economically attractive path for increase of the share of renewable energy. The optimum technological solution for use of biomass and required fuel resources have to be identified for energy planning and policy purposes. The aim of this study was to compare several wood fuel based energy conversion technologies from the technical and economical point of view. Three biomass conversion technologies for combined heat and electricity production (CHP) were analyzed: • CHP with steam turbine technology; • gasification CHP using gas engine; • bio-methane combined cycle CHP. Electricity prices for each alternative are presented. The results show the level of support needed for the analyzed renewable energy technologies and time period needed to reach price parity with the natural gas - fired combined cycle gas turbine (CCGT) CHPss. The results also show that bio-methane technology is most competitive when compared with CCGT among the considered technologies regarding fuel consumption and electricity production, but it is necessary to reduce investment costs to reach the electricity price parity with the natural gas CCGT.

Rusanova, Jekaterina; Markova, Darja; Bazbauers, Gatis; Valters, K?rlis

2013-12-01

325

Local antibody production in experimental pyelonephritis: amount, avidity, and immunoglobulin class.  

PubMed

LOCAL ANTIBODY FORMATION IN INFECTED RABBIT KIDNEYS WAS STUDIED WITH THREE TECHNIQUES: the ammonium sulfate precipitation technique, the enzyme-linked immunosorbent assay, and by binding of newly synthesized (14)C-labeled antibodies to heat-killed bacteria. Local antibody was detected by day 11 of infection with all three techniques, and a significant correlation was found in titers by all three methods. In these studies, antibody synthesized early was in IgG and IgA class, whereas IgM antibodies appeared later (day 20) in the antibody response. No maturation of avidity of local antibody was noted with time. Since it was necessary to use different animals at each test occasion, individual differences in avidity could account for failure to note an increase in avidity with time. PMID:4214768

Smith, J; Holmgren, J; Ahlstedt, S; Hanson, L A

1974-09-01

326

An evaluation of local thermal analysis of polymers on the sub-micrometer scale using heated scanning probe microscopy cantilevers.  

PubMed

A basic understanding of thermal properties of polymers is of fundamental importance for the development of advanced polymers. However, up to now, mainly bulk properties have been investigated. To characterize local softening processes in polymers, a local thermal analysis (LTA) technique is applied as an add-on to a scanning probe microscope. The development of a new generation of heatable cantilever probes enables thermal analysis in the sub-?m range. This method is based on an appropriate temperature calibration, which provides a reliable correlation of the applied voltage heating the tip and the actual temperature at the tip-sample interface. As the presented technique is more susceptible to environmental changes than comparable macroscopic methods, different parameters that might influence its performance are evaluated like a strong dependence on sample temperature. It is shown that the measured softening temperature on a polystyrene (PS) sample decreases from 102.2 to 66.4 °C as the temperature of the substrate is increased by 50 °C. The interaction between heat from the cantilever and the substrate is the reason for local sample softening, which opens new perspectives to understand the temperature calibration process using the melting standard method. A stepwise guideline for a suitable temperature calibration is provided. PMID:24654598

Fischinger, Thomas J; Laher, Martin; Hild, Sabine

2014-05-22

327

3D slicing of radiogenic heat production in Bahariya Formation, Tut oil field, North-Western Desert, Egypt.  

PubMed

A 3D block of radiogenic heat production was constructed from the subsurface total gamma ray logs of Bahariya Formation, Western Desert, Egypt. The studied rocks possess a range of radiogenic heat production varying from 0.21 ?Wm(-3) to 2.2 ?Wm(-3). Sandstone rocks of Bahariya Formation have higher radiogenic heat production than the average for crustal sedimentary rocks. The high values of density log of Bahariya Formation indicate the presence of iron oxides which contribute the uranium radioactive ores that increase the radiogenic heat production of these rocks. The average radiogenic heat production produced from the study area is calculated as 6.3 kW. The histogram and cumulative frequency analyses illustrate that the range from 0.8 to 1.2 ?Wm(-3) is about 45.3% of radiogenic heat production values. The 3D slicing of the reservoir shows that the southeastern and northeastern parts of the study area have higher radiogenic heat production than other parts. PMID:23291561

Al-Alfy, I M; Nabih, M A

2013-03-01

328

Vermont Biofuels Initiative: Local Production for Local Use to Supply a Portion of VermontâÂ?Â?s Energy Needs  

SciTech Connect

The Vermont Biofuels initiative (VBI) is the Vermont Sustainable Jobs Fund�s (VSJF) biomass-to-biofuels market development program. Vermont is a small state with a large petroleum dependency for transportation (18th in per capita petroleum consumption) and home heating (55% of all households use petroleum for heating). The VBI marks the first strategic effort to reduce Vermont�s dependency on petroleum through the development of homegrown alternatives. As such, it supports the four key priorities of the U.S. Department of Energy�s Multi-year Biomass Plan: 1.) Dramatically reduce dependence on foreign oil; 2.) Promote the use of diverse, domestic and sustainable energy resources; 3.) Reduce carbon emissions from energy production and consumption; 4.) Establish a domestic bioindustry. In 2005 VSJF was awarded with a $496,000 Congressionally directed award from U.S. Senator Patrick Leahy. This award was administered through the U.S. Department of Energy (DE-FG36- 05GO85017, hereafter referred to as DOE FY05) with $396,000 to be used by VSJF for biodiesel development and $100,000 to be used by the Vermont Department of Public Service for methane biodigester projects. The intent and strategic focus of the VBI is similar to another DOE funded organization� the Biofuels Center of North Carolina�in that it is a nonprofit driven, statewide biofuels market development effort. DOE FY05 funds were expensed from 2006 through 2008 for seven projects: 1) a feedstock production, logistics, and biomass conversion research project conducted by the University of Vermont Extension; 2) technical assistance in the form of a safety review and engineering study of State Line Biofuels existing biodiesel production facility; 3) technical assistance in the form of a safety review and engineering study of Borderview Farm�s proposed biodiesel production facility; 4) technology and infrastructure purchases for capacity expansion at Green Technologies, LLC, a waste vegetable biodiesel producer; 5) technical assistance in the form of feasibility studies for AgNorth Biopower LLC�s proposed multi-feedstock biodigester; 6) technology and infrastructure purchases for the construction of a �Cow Power� biodigester at Gervais Family Farm; and 7) the education and outreach activities of the Vermont Biofuels Association. DOE FY05 funded research, technical assistance, and education and outreach activities have helped to provide Vermont farmers and entrepreneurs with important feedstock production, feedstock logistics, and biomass conversion information that did not exist prior as we work to develop an instate biodiesel sector. The efficacy of producing oilseed crops in New England is now established: Oilseed crops can grow well in Vermont, and good yields are achievable given improved harvesting equipment and techniques. DOE FY05 funds used for technology and infrastructure development have expanded Vermont�s pool of renewable electricity and liquid fuel generation. It is now clear that on-farm energy production provides an opportunity for Vermont farmers and entrepreneurs to reduce on-farm expenditures of feed and fuel while providing for their energy security. Meanwhile they are developing new value-added revenue sources (e.g., locally produced livestock meal), retaining more dollars in the local economy, and reducing greenhouse gas emissions.

Scott Sawyer; Ellen Kahler

2009-05-31

329

Star-Product Functions in Higher-Spin Theory and Locality  

E-print Network

Properties of the functional classes of star-product elements associated with higher-spin gauge fields and gauge parameters are elaborated. Cohomological interpretation of the nonlinear higher-spin equations is given. An algebra ${\\mathcal H}$, where solutions of the nonlinear higher-spin equations are valued, is found. A conjecture on the classes of star-product functions underlying (non)local maps and gauge transformations in the nonlinear higher-spin theory is proposed.

M. A. Vasiliev

2015-02-08

330

Influence of local and external processes on the annual nitrogen cycle and primary productivity on Georges Bank: A 3-D  

E-print Network

Influence of local and external processes on the annual nitrogen cycle and primary productivity.V. All rights reserved. Keywords: Nitrogen cycle; Phytoplankton productivity; Modeling; Biological., Influence of local and external processes on the annual nitrogen cycle and primary productivity on Georges

Chen, Changsheng

331

The Impact of Consumer Ethnocentrism and Cultural Sensitivity on the Intention to Buy Local Products by Vietnamese Consumers  

Microsoft Academic Search

The purpose of this study is to examine the impact of consumer ethnocentrism and cultural sensitivity on the intention to buy local products by Vietnamese consumers. Three models hypothesising the relationships between consumer ethnocentrism, cultural sensitivity, foreign product judgment and intention to buy local products were developed. A sample of 549 consumers was surveyed to test these models via a

Nguyen D Tho; Nigel J Barrett

332

Local heat transfer in turbine disk-cavities. II - Rotor cooling with radial location injection of coolant  

NASA Astrophysics Data System (ADS)

The detailed radial distributions of rotor heat-transfer coefficients for three basic disk-cavity geometries applicable to gas turbines are presented. The coefficients are obtained over a range of parameters including disk rotational Reynolds numbers of 200,000 to 50,000, rotor/stator spacing-to-disk ratios of 0.025 to 0.15, and jet mass flow rates between 0.10 and 0.40 times the turbulent pumped flow rate of a free disk. The effects of a parallel rotor are analyzed, and strong variations in local Nusselt numbers for all but the rotational speed are pointed out and compared with the associated hub-injection data from a previous study. It is demonstrated that the overall rotor heat transfer is optimized by either the hub injection or radial location injection of a coolant, dependent on the configuration.

Bunker, R. S.; Metzger, D. E.; Wittig, S.

1990-06-01

333

Arabidopsis HEAT SHOCK TRANSCRIPTION FACTORA1b overexpression enhances water productivity, resistance to drought, and infection  

PubMed Central

Heat-stressed crops suffer dehydration, depressed growth, and a consequent decline in water productivity, which is the yield of harvestable product as a function of lifetime water consumption and is a trait associated with plant growth and development. Heat shock transcription factor (HSF) genes have been implicated not only in thermotolerance but also in plant growth and development, and therefore could influence water productivity. Here it is demonstrated that Arabidopsis thaliana plants with increased HSFA1b expression showed increased water productivity and harvest index under water-replete and water-limiting conditions. In non-stressed HSFA1b-overexpressing (HSFA1bOx) plants, 509 genes showed altered expression, and these genes were not over-represented for development-associated genes but were for response to biotic stress. This confirmed an additional role for HSFA1b in maintaining basal disease resistance, which was stress hormone independent but involved H2O2 signalling. Fifty-five of the 509 genes harbour a variant of the heat shock element (HSE) in their promoters, here named HSE1b. Chromatin immunoprecipitation-PCR confirmed binding of HSFA1b to HSE1b in vivo, including in seven transcription factor genes. One of these is MULTIPROTEIN BRIDGING FACTOR1c (MBF1c). Plants overexpressing MBF1c showed enhanced basal resistance but not water productivity, thus partially phenocopying HSFA1bOx plants. A comparison of genes responsive to HSFA1b and MBF1c overexpression revealed a common group, none of which harbours a HSE1b motif. From this example, it is suggested that HSFA1b directly regulates 55 HSE1b-containing genes, which control the remaining 454 genes, collectively accounting for the stress defence and developmental phenotypes of HSFA1bOx. PMID:23828547

Richard, François; Bowden, Laura; Morison, James I.L.; Mullineaux, Philip M.

2013-01-01

334

Identification of plasma structures with local enhancement in temperature and implication for intermittent heating of the solar wind  

NASA Astrophysics Data System (ADS)

Observationally, the solar wind temperature fluctuations are highly intermittent, especially at small scales. This phenomenon may contain information about solar wind intermittent heating and turbulence intermittent cascading. However, the physical nature of temperature intermittency is not yet clear. To clarify this issue, we identified the plasma structures associated with local temperature enhancements (may be called temperature peaks, TPs) according to their high normalized partial variance of increment (PVI) in temperature, which is the ratio between the local temperature difference for a time lag (24 seconds) and the standard deviation of those temperature differences. The plasma data observed by the WIND spacecraft in high-speed streams are used for this study. It is found that about 70% of the TPs are associated with linear magnetic holes (LMH) and 30% with TD-associated current sheets (TCSs). The TP-associated LMH have characteristic features, such as magnetic-amplitude dip of 30%-80% only in L (MVA) direction, extension of 80-800 proton gyro-radius, temperature anisotropy, and density enhancement in some cases, and plasma-beta peak which may be consistent with the mirror mode instability. However, some additional new features are also found. The cross-helicity (sigma_c) is in some cases high, which is not consistent with predictions for the mirror mode instability, but may indicate a possible relation with Alfven waves. Some cases show dips in total pressure, perhaps indicating non-static convection of the structures. The high percentage of LMHs associated with TPs may suggest that solar wind intermittent heating is mainly due to the processes which create LMH, such as the cyclotron resonance heating, mirror mode instability, or obliquely propagating large-amplitude Alfven waves. Magnetic reconnection in TD-associated current sheets may also contribute considerably to intermittent heating. How turbulence with intermittent cascade can produce such structures, as LMHs and TCSs, will be a topic for future studies.

Wang, X.; Tu, C.; He, J.; Marsch, E.; Wang, L.

2013-12-01

335

Numerical research of heat and mass transfer at the ignition of system "fabric - combustible liquid - oxidant" by the local energy source  

NASA Astrophysics Data System (ADS)

A numerical research was executed for macroscopic regularities determination of heat and mass transfer processes under the conditions of phase transformation and chemical reaction at the ignition of vapour coming from fabrics impregnated by typical combustible liquid into oxidant area at the local power supply. Limit conditions of heterogeneous system "fabric - combustible liquid - oxidant" ignition at the heating of single metal particle was established. Dependences of ignition delay time on temperature and rates of local power source were obtained.

Glushkov, Dmitrii O.; Kuznetsov, Genii V.; Strizhak, Pavel A.

2015-01-01

336

Skin AVA and capillary dilatation and constriction induced by local skin heating  

Microsoft Academic Search

In conscious sheep, total femoral blood flow and flow through arteriovenous anastomoses (AVAs) and capillaries (CAP) in skin of the hindleg were measured employing electromagnetic and radioactive microsphere techniques. Core temperature (Tc) was manipulated using intravascular heat exchangers and hindleg skin temperature (Tsk) was manipulated by immersion in temperature controlled water. WithTc set 1°C above normal, AVA flow was highest

J. R. S. Hales; C. Jessen; A. A. Fawcett; R. B. King

1985-01-01

337

Combined thermocapillary and natural convection in rectangular containers with localized heating  

Microsoft Academic Search

Combined thermocapillary and natural convection in rectangular containers is investigated experimentally and theoretically. The fluid is heated by a thin wire placed along the free surface. In the parametric range investigated herein, buoyancy alters the thermocapillary flow significantly. The flow field is confined to a relatively small region near the free surface due to thermal stratification. The vertical dimension of

Kyu-Jung Lee; Yasuhiro Kamotani; Shinichi Yoda

2002-01-01

338

Local Measurement of NonClassical Ion Heating During Magnetic Reconnection  

E-print Network

â??enic flows [9]. In SSX (Swarthmore Spheromak Experiment), Alfvâ??enic ion jets correlated with reconnection], and it has been proposed that the million degree corona is heated by turbulent reconnection [4]. In the Earth of this research, would have important implications. Laboratory experiments have made important contributions

339

Local Measurement of Non-Classical Ion Heating During Magnetic Reconnection  

E-print Network

´enic flows [9]. In SSX (Swarthmore Spheromak Experiment), Alfv´enic ion jets correlated with reconnection], and it has been proposed that the million degree corona is heated by turbulent reconnection [4]. In the Earth of this research, would have important implications. Laboratory experiments have made important contributions

340

Measurement of Local Heat Flux to Membrane Water-Walls in Steam Boilers  

Microsoft Academic Search

1. Abstract A heat flux entering steam generating tubes in power station boilers may be a critical factor in considering the safety of the tubes. The knowledge of the distribution and magnitude of this flux during the operation of the power boiler is very important. The design of a modern boiler furnace requires the computation of furnace wall metal temperatures

Dawid Taler

2008-01-01

341

Anaerobic bio-hydrogen production using pre-heated river sediments as seed sludge.  

PubMed

Anaerobic bio-hydrogen production is the focus in the field of bio-energy resources. In this paper, a series of batch experiments were conducted to investigate the effects of several factors on anaerobic bio-hydrogen producing process carried out by pre-heated river sediments. The results showed that several factors such as substrate and its concentration, temperature and the initial pH value could affect the anaerobic bio-hydrogen production in different levels. At 35 degrees C and the initial pH of 6.5, using glucose of 20,000 mg COD/L as substrate, the highest hydrogen production of 323.8 ml-H2/g TVS in a 100 ml batch reactor was reached, the specific hydrogen production rate was 37.7 ml-H2/g TVS h, and the hydrogen content was 51.2%. Thereafter using the same pre-heated river sediments as seed sludge, continuous anaerobic bio-hydrogen production was achieved successfully in a lab-scale CSTR with gas-separator. At the organic loading rate of 36 kg COD/m3 d, the highest hydrogen production was 6.3-6.7 l-H2/l-reactor d, the specific hydrogen production was 1.3-1.4 mol-H2/mol-glucose, and the hydrogen content in the gas was 52.3%. The effluent of the bio-reactor contained some small molecular organics, mainly including ethanol, acetate, butyrate and their molar proportion is 1:1:0.6. PMID:16459774

Zuo, J; Zuo, Y; Zhang, W; Chen, J

2005-01-01

342

Detailed measurements of local heat transfer coefficients in turbulent flow through smooth and rib-roughened serpentine passages with a 180° sharp bend  

Microsoft Academic Search

An experimental study is performed to investigate heat transfer and fluid flow in two straight, rectangular channels with a 180° sharp bend. Ribs are attached to two opposite walls with an angle of 90° or 60° to the flow. More than 450 thermocouples are used to monitor detailed distributions of local heat transfer coefficients over the four wall surfaces of

S. Mochizuki; A. Murata; R. Shibata; Wen-Jei Yang

1998-01-01

343

The Cultural Production of Locality: Reclaiming the 'European City' in Post-Wall Berlin  

Microsoft Academic Search

Berlin's post-1989 rebuilding is used to explore the role of cultural professionals, exemplified by architects and urban planners, in the production of locality. Drawing on an analysis of architectural debates, competitions and building projects, the article traces how the model of the 'European city' became the dominant paradigm of urban reconstruction in the 1990s and what precisely was understood by

VIRAG MOLNAR

2010-01-01

344

RF identification and localization - recent steps towards the internet of things in metal production and processing  

Microsoft Academic Search

This paper gives an overview on recent radio frequency local positioning and identification techniques applied in steel production and processing. It is shown that it is required to combine different radio technologies in order to track and trace the goods involved in the manufacturing processes reliably and continuously. In addition the applied components must be carefully adapted to the given

Martin Vossiek; Robert Miesen; Joachim Wittwer

2010-01-01

345

Appropriation of the Eclipse Ecosystem: Local Integration of Global Network Production  

E-print Network

Appropriation of the Eclipse Ecosystem: Local Integration of Global Network Production Gunnar source projects. Research on such software ecosystems shows that collaboration patterns in the software presents an empirical study on the practices of appropriating the Eclipse ecosystem as an example

346

Genetic variations alter production and behavioral responses following heat stress in 2 strains of laying hens.  

PubMed

Genetic differences alter the type and degree of hens' responses and their ability to adapt to a stressor. This study examined the effects of genotypic variations on the productivity and behavior of laying hens following heat stress (HS). Two strains of White Leghorn hens were used: DXL (Dekalb XL), a commercial strain individually selected for egg production and KGB (kind, gentle bird), a strain selected for high group productivity and survivability. Ninety hens (48 DXL and 42 KGB) at 28 wk of age were randomly assigned to either a hot (H: mean = 32.6°C) or control (C: mean = 24.3°C) treatment and housed in pairs by strain for 9 d. Egg production and quality, behavior, body and organ weights, and circulating hormone concentrations were measured. Heat-stressed hens had lower egg production [adjusted (adj) P < 0.001] than their respective controls. Among H-DXL hens, egg weight tended to be reduced at d 1 and was reduced at d 9 (adj P = 0.007), but was reduced only at d 9 among H-KGB hens (adj P = 0.007). Eggshell thickness was also reduced among H hens at d 9 (adj P = 0.007), especially among H-KGB hens (adj P = 0.01). Plasma triiodothyronine concentration was reduced among H-hens (adj P = 0.01), especially among H-DXL hens (adj P = 0.01). Neither temperature nor strain affected the plasma thyroxine and plasma and yolk corticosterone concentrations. Heat-stressed hens spent less time walking (adj P = 0.001) and more time drinking (adj P = 0.007) and resting (adj P = 0.001) than C-hens. The results indicate that although HS reduced production and caused behavioral changes among hens from both strains, the responses differed by genotype. The data provide evidence that genetic selection is a useful strategy for reducing HS response in laying hens. The results provide insights for conducting future studies to develop heat-resistant strains to improve hen well-being, especially under the current commercial conditions. PMID:23300291

Mack, L A; Felver-Gant, J N; Dennis, R L; Cheng, H W

2013-02-01

347

Results from the Phoenix Urban Heat Island (UHI) experiment: effects at the local, neighbourhood and urban scales  

NASA Astrophysics Data System (ADS)

This paper reports on the analysis of results from a large urban heat island experiment (UHI) performed in Phoenix (AZ) in April 2008. From 1960 to 2000, the city of Phoenix experienced a minimum temperature rise of 0.47 °C per decade, which is one of the highest rates in the world for a city of this size (Golden, 2004). Contemporaneously, the city has recorded a rapid enlargement and large portion of the land and desert vegetation have been replaced by buildings, asphalt and concrete (Brazel et al., 2007, Emmanuel and Fernando, 2007). Besides, model predictions show that minimum air temperatures for Phoenix metropolitan area in future years might be even higher than 38 °C. In order to make general statements and mitigation strategies of the UHI phenomenon in Phoenix and other cities in hot arid climates, a one-day intensive experiment was conducted on the 4th-5th April 2008 to collect surface and ambient temperatures within various landscapes in Central Phoenix. Inter alia, infrared thermography (IRT) was used for UHI mapping. The aim was to investigate UHI modifications within the city of Phoenix at three spatial scales i.e. the local (Central Business District, CBD), the neighborhood and the city scales. This was achieved by combining IRT measurements taken at ground level by mobile equipment (automobile-mounted and pedicab) and at high elevation by a helicopter. At local scale detailed thermographic images of about twenty building façades and several street canyons were collected. In total, about two thousand images were taken during the 24-hour campaign. Image analysis provides detailed information on building surface and pavement temperatures at fine resolution (Hedquist et al. 2009, Di Sabatino et al. 2009). This unique dataset allows us several investigations on local air temperature dependence on albedo, building thermal inertia, building shape and orientation and sky view factors. Besides, the mosaic of building façade temperatures are being analyzed in terms of local buoyancy fluxes and possible wind flow modifications by such thermally driven flows will be elucidated. The results are of consequence for understanding microclimate of large cities in order to derive urbanizations schemes for numerical models and to set-up suitable heat mitigation strategies. REFERENCES Brazel, AJ, Gober, P., Lee, S., Grossman-Clarke, S., Zehnder, J., Hedquist, B. and Comparri, E 2007: Dynamics and determinants of urban heat island change (1990-2004) with Phoenix, Arizona, USA. Climate Research 33, 171-182. Di Sabatino S, Hedquist BC, Carter W, Leo LS, Fernando HJS. 2009. Phoenix urban heat island experiment: effects of built elements. Proceedings of the Eighth Symposium on the Urban Environment, Phoenix, Arizona. Emmanuel, R. and Fernando HJS 2007: Effects of urban form and thermal properties in urban heat island mitigation in hot humid and hot arid climates: The cases of Colombo, Sri Lanka and Phoenix, USA. Climate Research 34, 241-251. Golden JS. 2004. The built environment induced urban heat island in rapidly urbanizing arid regions: a sustainable urban engineering complexity. Environmental Sciences 1(4):321-349. Hedquist, BC, Brazel, AJ, Di Sabatino, S., Carter, W. and Fernando, HJS 2009: Phoenix urban heat island experiment: micrometeorological aspects. Proceedings of the Eighth Symposium on the Urban Environment, Phoenix, Arizona.

di Sabatino, S.; Leo, L. S.; Hedquist, B. C.; Carter, W.; Fernando, H. J. S.

2009-04-01

348

Turbulent Heat Fluxes in Urban Areas: Observations and a Local-Scale Urban Meteorological Parameterization Scheme (LUMPS).  

NASA Astrophysics Data System (ADS)

A linked set of simple equations specifically designed to calculate heat fluxes for the urban environment is presented. This local-scale urban meteorological parameterization scheme (LUMPS), which has similarities to the hybrid plume dispersion model (HPDM) scheme, requires only standard meteorological observations and basic knowledge of surface cover. LUMPS is driven by net all-wave radiation. Heat storage by the urban fabric is parameterized from net all-wave radiation and surface cover information using the objective hysteresis model (OHM). The turbulent sensible and latent heat fluxes are calculated using the available energy and are partitioned using the approach of de Bruin and Holtslag, and Holtslag and van Ulden. A new scheme to define the Holtslag and van Ulden and parameters for urban environments is presented; is empirically related to the plan fraction of the surface that is vegetated or irrigated, and a new urban value of captures the observed delay in reversal of the sign of the sensible heat flux in the evening. LUMPS is evaluated using field observations collected in seven North American cities (Mexico City, Mexico; Miami, Florida; Tucson, Arizona; Los Angeles and Sacramento, California; Vancouver, British Columbia, Canada; and Chicago, Illinois). Performance is shown to be better than that for the standard HPDM preprocessor scheme. Most improvement derives from the inclusion of the OHM for the storage heat flux and the revised coefficient. The scheme is expected to have broad utility in models used to calculate air pollution dispersion and the mixing depths of urban areas or to provide surface forcing for mesoscale models of urban regions.

Grimmond, C. S. B.; Oke, T. R.

2002-07-01

349

Heat removal from high temperature tubular solid oxide fuel cells utilizing product gas from coal gasifiers.  

SciTech Connect

In this work we describe the results of a computer study used to investigate the practicality of several heat exchanger configurations that could be used to extract heat from tubular solid oxide fuel cells (SOFCs) . Two SOFC feed gas compositions were used in this study. They represent product gases from two different coal gasifier designs from the Zero Emission Coal study at Los Alamos National Laboratory . Both plant designs rely on the efficient use of the heat produced by the SOFCs . Both feed streams are relatively rich in hydrogen with a very small hydrocarbon content . One feed stream has a significant carbon monoxide content with a bit less hydrogen . Since neither stream has a significant hydrocarbon content, the common use of the endothermic reforming reaction to reduce the process heat is not possible for these feed streams . The process, the method, the computer code, and the results are presented as well as a discussion of the pros and cons of each configuration for each process .

Parkinson, W. J. (William Jerry),

2003-01-01

350

Radiation heat savings in polysilicon production: Validation of results through a CVD laboratory prototype  

NASA Astrophysics Data System (ADS)

This work aims at a deeper understanding of the energy loss phenomenon in polysilicon production reactors by the so-called Siemens process. Contributions to the energy consumption of the polysilicon deposition step are studied in this paper, focusing on the radiation heat loss phenomenon. A theoretical model for radiation heat loss calculations is experimentally validated with the help of a laboratory CVD prototype. Following the results of the model, relevant parameters that directly affect the amount of radiation heat losses are put forward. Numerical results of the model applied to a state-of-the-art industrial reactor show the influence of these parameters on energy consumption due to radiation per kilogram of silicon produced; the radiation heat loss can be reduced by 3.8% when the reactor inner wall radius is reduced from 0.78 to 0.70 m, by 25% when the wall emissivity is reduced from 0.5 to 0.3, and by 12% when the final rod diameter is increased from 12 to 15 cm.

Ramos, A.; del Cañizo, C.; Valdehita, J.; Zamorano, J. C.; Luque, A.

2013-07-01

351

Metabolic heat production as a measure of macrophage response to particles from orthopedic implant materials.  

PubMed

An in vitro method to gauge metabolic heat response of macrophages (MØ) to particulates is described. Whereas the majority of work cited relies on chemical analysis to assess MØ response to particles, we have used isothermal microcalorimetry (IMC) for direct continuous measurement of metabolic heat production to gauge the response. IMC is a screening method, in that it ensures that no energy-consuming phagocytic response goes undetected, and that the aggregate metabolic magnitude of the responses is determined. A four-well IMC was used in all microcalorimetric measurements. To accommodate "zero-time" monitoring of the interaction of particles and cells, a set of identical test chambers was constructed for use in the IMC. MØs were injected from outside the IMC onto particles contained in collagen or gelatin on glass coverslips at the bottom of each chamber. IMC runs were performed using MØs only, MØs and lipopolysaccharide (LPS) positive control, and MØs and clean or LPS-bound particles of either high-density polyethylene (HDPE) or cobalt-chrome alloy (CoCr). Total heat produced by the negative controls (MØs alone) was lower than for MØ exposure to LPS or particles. The trend was a higher response for LPS-bound HDPE compared with clean HDPE particles, though not significant. In conclusion, our results have shown that IMC can be used to detect the heat associated with the phagocytosis of particulate materials by MØs in vitro. PMID:11745550

Charlebois, S J; Daniels, A U; Smith, R A

2002-01-01

352

Gas production and transport during bench-scale electrical resistance heating of water and trichloroethene  

NASA Astrophysics Data System (ADS)

The effective remediation of chlorinated solvent source zones using in situ thermal treatment requires successful capture of gas that is produced. Replicate electrical resistance heating experiments were performed in a thin bench-scale apparatus, where water was boiled and pooled dense non-aqueous phase liquid (DNAPL) trichloroethene (TCE) and water were co-boiled in unconsolidated silica sand. Quantitative light transmission visualization was used to assess gas production and transport mechanisms. In the water boiling experiments, nucleation, growth and coalescence of the gas phase into connected channels were observed at critical gas saturations of Sgc = 0.233 ± 0.017, which allowed for continuous gas transport out of the sand. In experiments containing a colder region above a target heated zone, condensation prevented the formation of steam channels and discrete gas clusters that mobilized into colder regions were trapped soon after discontinuous transport began. In the TCE-water experiments, co-boiling at immiscible fluid interfaces resulted in discontinuous gas transport above the DNAPL pool. Redistribution of DNAPL was also observed above the pool and at the edge of the vapor front that propagated upwards through colder regions. These results suggest that the subsurface should be heated to water boiling temperatures to facilitate gas transport from specific locations of DNAPL to extraction points and reduce the potential for DNAPL redistribution. Decreases in electric current were observed at the onset of gas phase production, which suggests that coupled electrical current and temperature measurements may provide a reliable metric to assess gas phase development.

Hegele, P. R.; Mumford, K. G.

2014-09-01

353

Simulation of localized fast-ion heat loads in test blanket module simulation experiments on DIII-D  

NASA Astrophysics Data System (ADS)

Infrared imaging of hot spots induced by localized magnetic perturbations using the test blanket module (TBM) mock-up on DIII-D is in good agreement with beam-ion loss simulations. The hot spots were seen on the carbon protective tiles surrounding the TBM as they reached temperatures over 1000 °C. The localization of the hot spots on the protective tiles is in fair agreement with fast-ion loss simulations using a range of codes: ASCOT, SPIRAL and OFMCs while the codes predicted peak heat loads that are within 30% of the measured ones. The orbit calculations take into account the birth profile of the beam ions as well as the scattering and slowing down of the ions as they interact with the localized TBM field. The close agreement between orbit calculations and measurements validate the analysis of beam-ion loss calculations for ITER where ferritic material inside the tritium breeding TBMs is expected to produce localized hot spots on the first wall.

Kramer, G. J.; McLean, A.; Brooks, N.; Budny, R. V.; Chen, X.; Heidbrink, W. W.; Kurki-Suonio, T.; Nazikian, R.; Koskela, T.; Schaffer, M. J.; Shinohara, K.; Snipes, J. A.; Van Zeeland, M. A.

2013-12-01

354

Optimisation of magnesium alloy stamping with local heating and cooling using the finite element method  

Microsoft Academic Search

A new deep-drawing process with a localised heating and cooling technique was verified to improve sheet forming of a magnesium alloy which is impossible to form by conventional methods at room temperature. Deep-drawing experiments were conducted at a temperature of about 400°C for the blank and deep-drawing tool (holder and die) and at a punch speed of 200mm\\/min. In the

S. Yoshihara; B. J. MacDonald; H. Nishimura; H. Yamamoto; K. Manabe

2004-01-01

355

Hydrodynamics and local heat transfer measurements in a bubble column with suspension of yeast  

Microsoft Academic Search

Hydrodynamics and heat transfer were investigated in a 0.28m diameter slurry bubble column for air–water–yeast cells system. Yeast cells of about 8?m diameter were used and the effects of gas velocity and yeast concentrations were studied. Gas holdups exhibited a maximum value around a gas superficial velocity of 0.10m\\/s when foam height was included. Without the foam layer, gas holdups

A Prakash; A Margaritis; H Li; M. A Bergougnou

2001-01-01

356

Comparison of the effects of millimeter wave irradiation, general bath heating, and localized heating on neuronal activity in the leech ganglion  

NASA Astrophysics Data System (ADS)

The use of electrically-induced neuromodulation has grown in importance in the treatment of multiple neurological disorders such as Parkinson's disease, dystonia, epilepsy, chronic pain, cluster headaches and others. While electrical current can be applied locally, it requires placing stimulation electrodes in direct contact with the neural tissue. Our goal is to develop a method for localized application of electromagnetic energy to the brain without direct tissue contact. Toward this goal, we are experimenting with the wireless transmission of millimeter wave (MMW) energy in the 10-100 GHz frequency range, where penetration and focusing can be traded off to provide non-contact irradiation of the cerebral cortex. Initial experiments have been conducted on freshly-isolated leech ganglia to evaluate the real-time changes in the activity of individual neurons upon exposure to the MMW radiation. The initial results indicate that low-intensity MMWs can partially suppress the neuronal activity. This is in contrast to general bath heating, which had an excitatory effect on the neuronal activity. Further studies are underway to determine the changes in the state of the membrane channels that might be responsible for the observed neuromodulatory effects.

Romanenko, Sergii; Siegel, Peter H.; Wagenaar, Daniel A.; Pikov, Victor

2013-02-01

357

NATCOR -Xpress case study Margaret Oil produces three products: gasoline, jet fuel, and heating oil. The average  

E-print Network

be distilled. It costs £0.10 to distill a barrel of oil and the result of the distillation is 0.25 barrelsNATCOR - Xpress case study Margaret Oil produces three products: gasoline, jet fuel, and heating oil. The average octane levels must be at least 8.5 for gasoline, 7 for jet fuel, and 4.5 for heating

Hall, Julian

358

Crustal radiogenic heat production and the selective survival of ancient continental crust  

NASA Technical Reports Server (NTRS)

It is pointed out that the oldest terrestrial rocks have so far revealed no evidence of the impact phase of earth evolution. This observation suggests that processes other than impact were dominant at the time of stabilization of these units. However, a use of the oldest terrestrial rocks as a sample of the early terrestrial crust makes it necessary to consider the possibility that these rocks may represent a biased sample. In the present study, the global continental heat flow data set is used to provide further evidence that potassium, uranium, and thorium abundances are, on the average, low in surviving Archean crust relative to younger continental crust. An investigation is conducted of the implications of relatively low crustal radiogenic heat production to the stabilization of early continental crust, and possible Archean crustal stabilization models are discussed.

Morgan, P.

1985-01-01

359

Crustal radiogenic heat production and the selective survival of ancient continental crust  

NASA Technical Reports Server (NTRS)

It is pointed out that the oldest terrestrial rocks have so far revealed no evidence of the impact phase of Earth evolution. This observation suggests that processes other than impact were dominant at the time of stabilization of these units. However, a use of the oldest terrestrial rocks as a sample of the early terrestrial crust makes it necessary to consider the possibility that these rocks may represent a biased sample. In the present study, the global continental heat flow data set is used to provide further evidence that potassium, uranium, and thorium abundances are, on the average, low in surviving Archean crust relative to younger continental crust. An investigation is conducted of the implications of relatively low crustal radiogenic heat production to the stabilization of early continental crust, and possible Archean crustal stabilization models are discussed.

Morgan, P.

1985-01-01

360

Comment on 'A reinterpretation of the linear heat flow and heat production relationship for the exponential model of the heat production in the crust' by R.N. Singh & J.G. Negi.  

USGS Publications Warehouse

In their recent paper, Singh & Negi, (This journal, 57, 741-744) contend that if thd slope of the empirical linear relation between heat flow and heat production is interpreted as the decay-length of an exponential depth-distribution of sources, a discrepancy rises, whereas if it is interpreted as the depth of a step distribution, it does not. I should like to point out that their discrepancy follows from their arbitrary assumption of one of a range of physical possibilities unconstrained by the observations; with an equally valid alternate assumption (Lachenbruch 1970) the discrepancy disappears. In any case such discrepancies are probably minor compared to physical difficulties that arise from the step model, and to uncertainties introduced by other assumptions in any simple model.-Author

Lachenbruch, A.H.

1980-01-01

361

Characterization of smallholder pig production system: productive and reproductive performances of local and crossbred pigs in Sikkim Himalayan region.  

PubMed

The present study was conducted to know the smallholder pig production system in tribal areas of Sikkim State, India. Two hundred tribal farmers were selected randomly from the North and East District of the state. Information on socio-economic characteristics of farmers (gender, occupation, educational status, and farming experience), management practices, disease prevalence, and economics in pig production was collected. The study recorded the mean land holding as 1.2 ± 0.8 ha, and the number of pigs per farm was 5.0 ± 0.28. Pigs were mainly kept as a source of income, and 70 % of farmers reared crossbreed pigs. Ninety percent (90 %) of respondents practiced the intensive system of management whereby kitchen wastes along with cooked mixture comprising maize bhusa, mustard oil cake, pseudostem of banana, tuber, stem, and plant leaves were used to feed their animals. About 40.5 % of farmers procured their breeding stock from government farms that had good records and utilized veterinary services like timely vaccination and deworming. The diseases prevalent in the study area were swine fever, diarrhea, helminthoses, sarcoptic mange, pneumonia, etc. The litter sizes at birth (local, 4.3 ± 0.45; crossbreed, 7.2 ± 0.33), at weaning (local, 2.79 ± 0.24; crossbreed, 6.1 ± 0.21), and age at first farrowing (local, 365.39 ± 7.96 days; crossbreed, 337.24 ± 8.79 days) were recorded. Production costs of meat extracted from local and crossbred pigs were 1.08 $/kg and 0.86 $/kg, respectively. PMID:23636408

Nath, B G; Pathak, P K; Ngachan, S V; Tripathi, A K; Mohanty, A K

2013-10-01

362

Solar Radiation during Rewarming from Torpor in Elephant Shrews: Supplementation or Substitution of Endogenous Heat Production?  

PubMed Central

Many small mammals bask in the sun during rewarming from heterothermy, but the implications of this behaviour for their energy balance remain little understood. Specifically, it remains unclear whether solar radiation supplements endogenous metabolic thermogenesis (i.e., rewarming occurs through the additive effects of internally-produced and external heat), or whether solar radiation reduces the energy required to rewarm by substituting (i.e, replacing) metabolic heat production. To address this question, we examined patterns of torpor and rewarming rates in eastern rock elephant shrews (Elephantulus myurus) housed in outdoor cages with access to either natural levels of solar radiation or levels that were experimentally reduced by means of shade cloth. We also tested whether acclimation to solar radiation availability was manifested via phenotypic flexibility in basal metabolic rate (BMR), non-shivering thermogenesis (NST) capacity and/or summit metabolism (Msum). Rewarming rates varied significantly among treatments, with elephant shrews experiencing natural solar radiation levels rewarming faster than conspecifics experiencing solar radiation levels equivalent to approximately 20% or 40% of natural levels. BMR differed significantly between individuals experiencing natural levels of solar radiation and conspecifics experiencing approximately 20% of natural levels, but no between-treatment difference was evident for NST capacity or Msum. The positive relationship between solar radiation availability and rewarming rate, together with the absence of acclimation in maximum non-shivering and total heat production capacities, suggests that under the conditions of this study solar radiation supplemented rather than substituted metabolic thermogenesis as a source of heat during rewarming from heterothermy. PMID:25853244

Thompson, Michelle L.; Mzilikazi, Nomakwezi; Bennett, Nigel C.; McKechnie, Andrew E.

2015-01-01

363

Variation of corrosion behavior of candidate heat exchanger alloys with local oxygen partial pressure in a 0. 6 meter diameter AFBC  

SciTech Connect

The research reviewed here is in support of a program in which a coal-fired atmospheric fluidized-bed combustor (AFBC) is being designed to supply heat to a closed-cycle gas turbine co-generation system. The objective is to develop a system which could utilize high-sulfur coal. The major technical challenge is the design and development of the in-bed primary heat exchanger, which is required to operate near the bed temperature (1172 K, 1650 F). The purpose of this research was to characterize the types of corrosive environments encountered in the AFBC by monitoring the oxygen partial pressure at the exposure locations and to correlate the corrosion behavior of the exposed alloys to the local oxygen partial pressure measurements. Results were given for Incoloy 800, FeCr A/Y cladding, and nickel-base alloys. The relationships between the observed corrosion products and measured oxygen partial pressures suggest that the deposits formed in the AFBC had porosity sufficient such that intimate gas-metal contact was possible. 3 figures. (DP)

Not Available

1983-08-01

364

Millimeter Wave Detection of Localized Anomalies in the Space Shuttle External Fuel Tank Insulating Foam and Acreage Heat Tiles  

NASA Technical Reports Server (NTRS)

The Space Shuttle Columbia's catastrophic accident emphasizes the growing need for developing and applying effective, robust and life-cycle oriented nondestructive testing (NDT) methods for inspecting the shuttle external fuel tank spray on foam insulation (SOFI) and its protective acreage heat tiles. Millimeter wave NDT techniques were one of the methods chosen for evaluating their potential for inspecting these structures. Several panels with embedded anomalies (mainly voids) were produced and tested for this purpose. Near-field and far-field millimeter wave NDT methods were used for producing millimeter wave images of the anomalies in SOFI panel and heat tiles. This paper presents the results of an investigation for the purpose of detecting localized anomalies in two SOFI panels and a set of heat tiles. To this end, reflectometers at a relatively wide range of frequencies (Ka-band (26.5 - 40 GHz) to W-band (75 - 110 GHz)) and utilizing different types of radiators were employed. The results clearly illustrate the utility of these methods for this purpose.

Kharkovsky, S.; Case, J. T.; Zoughi, R.; Hepburn, F.

2005-01-01

365

The impact of local geochemical variability on quantifying hillslope soil production and chemical weathering  

NASA Astrophysics Data System (ADS)

Soil-mantled upland landscapes are widespread across the habitable world, support extensive life, and are the interface between the atmosphere, hydrosphere, and lithosphere but typically are not cultivated. Soil found across such landscapes fits the conceptual framework of a physically mobile layer derived from the underlying parent material along with some locally derived organic content. The extent and persistence of these upland soils depend on the long-term balance between soil production and erosion. Here we briefly review methods used to quantify the physical and chemical processes of soil production and erosion and revisit three granitic study areas in southeastern Australia and northern California that enabled early quantification of the soil production function and topographic controls on chemical weathering. We then present new major and trace element data from 2-m by 2-m pits dug at each field site to quantify local variability of Zr concentrations and the chemical index of alteration (CIA), weathering indices used to determine chemical weathering rates and extents in soils and saprolites. Using both new and previously published data, we compare differences between local variability and regional, as well as intersite variability of these important indices. For each of the 2-m pits, we collected 25 samples and found that the simple mean and the 2? standard deviation best describe the local variation in the data. We also find that the variability in the 2-m pit data lies within variability observed in the same data from samples collected in individual soil pits across each of the field sites and that the differences between sites are consistent with previously published results. These observations highlight the importance of quantifying local scale variability in studies that use similar, multifaceted measurements to quantify hillslope soil production and erosion processes.

Heimsath, Arjun M.; Burke, Benjamin C.

2013-10-01

366

Optimization of a One-Step Heat-Inducible In Vivo Mini DNA Vector Production System  

PubMed Central

While safer than their viral counterparts, conventional circular covalently closed (CCC) plasmid DNA vectors offer a limited safety profile. They often result in the transfer of unwanted prokaryotic sequences, antibiotic resistance genes, and bacterial origins of replication that may lead to unwanted immunostimulatory responses. Furthermore, such vectors may impart the potential for chromosomal integration, thus potentiating oncogenesis. Linear covalently closed (LCC), bacterial sequence free DNA vectors have shown promising clinical improvements in vitro and in vivo. However, the generation of such minivectors has been limited by in vitro enzymatic reactions hindering their downstream application in clinical trials. We previously characterized an in vivo temperature-inducible expression system, governed by the phage ? pL promoter and regulated by the thermolabile ? CI[Ts]857 repressor to produce recombinant protelomerase enzymes in E. coli. In this expression system, induction of recombinant protelomerase was achieved by increasing culture temperature above the 37°C threshold temperature. Overexpression of protelomerase led to enzymatic reactions, acting on genetically engineered multi-target sites called “Super Sequences” that serve to convert conventional CCC plasmid DNA into LCC DNA minivectors. Temperature up-shift, however, can result in intracellular stress responses and may alter plasmid replication rates; both of which may be detrimental to LCC minivector production. We sought to optimize our one-step in vivo DNA minivector production system under various induction schedules in combination with genetic modifications influencing plasmid replication, processing rates, and cellular heat stress responses. We assessed different culture growth techniques, growth media compositions, heat induction scheduling and temperature, induction duration, post-induction temperature, and E. coli genetic background to improve the productivity and scalability of our system, achieving an overall LCC DNA minivector production efficiency of ?90%.We optimized a robust technology conferring rapid, scalable, one-step in vivo production of LCC DNA minivectors with potential application to gene transfer-mediated therapeutics. PMID:24586704

Wettig, Shawn; Slavcev, Roderick A.

2014-01-01

367

Optimization of a one-step heat-inducible in vivo mini DNA vector production system.  

PubMed

While safer than their viral counterparts, conventional circular covalently closed (CCC) plasmid DNA vectors offer a limited safety profile. They often result in the transfer of unwanted prokaryotic sequences, antibiotic resistance genes, and bacterial origins of replication that may lead to unwanted immunostimulatory responses. Furthermore, such vectors may impart the potential for chromosomal integration, thus potentiating oncogenesis. Linear covalently closed (LCC), bacterial sequence free DNA vectors have shown promising clinical improvements in vitro and in vivo. However, the generation of such minivectors has been limited by in vitro enzymatic reactions hindering their downstream application in clinical trials. We previously characterized an in vivo temperature-inducible expression system, governed by the phage ? pL promoter and regulated by the thermolabile ? CI[Ts]857 repressor to produce recombinant protelomerase enzymes in E. coli. In this expression system, induction of recombinant protelomerase was achieved by increasing culture temperature above the 37°C threshold temperature. Overexpression of protelomerase led to enzymatic reactions, acting on genetically engineered multi-target sites called "Super Sequences" that serve to convert conventional CCC plasmid DNA into LCC DNA minivectors. Temperature up-shift, however, can result in intracellular stress responses and may alter plasmid replication rates; both of which may be detrimental to LCC minivector production. We sought to optimize our one-step in vivo DNA minivector production system under various induction schedules in combination with genetic modifications influencing plasmid replication, processing rates, and cellular heat stress responses. We assessed different culture growth techniques, growth media compositions, heat induction scheduling and temperature, induction duration, post-induction temperature, and E. coli genetic background to improve the productivity and scalability of our system, achieving an overall LCC DNA minivector production efficiency of ? 90%.We optimized a robust technology conferring rapid, scalable, one-step in vivo production of LCC DNA minivectors with potential application to gene transfer-mediated therapeutics. PMID:24586704

Nafissi, Nafiseh; Sum, Chi Hong; Wettig, Shawn; Slavcev, Roderick A

2014-01-01

368

Local heat-transfer measurements on a large, scale-model turbine blade airfoil using a composite of a heater element and liquid crystals  

NASA Technical Reports Server (NTRS)

Local heat transfer coefficients were experimentally mapped along the midchord of a five-time-size turbine blade airfoil in a static cascade operated at room temperature over a range of Reynolds numbers. The test surface consisted of a composite of commercially available materials: a mylar sheet with a layer of cholesteric liquid crystals, that change color with temperature, and a heater sheet made of a carbon-impregnated paper, that produces uniform heat flux. After the initial selection and calibration of the composite sheet, accurate, quantitative, and continuous heat transfer coefficients were mapped over the airfoil surface. The local heat transfer coefficients are presented for Reynolds numbers from 2.8 x 10 to the 5th power to 7.6 x 10 to the 5th power. Comparisons are made with analytical values of heat transfer coefficients obtained from the STAN5 boundary layer code. Also, a leading edge separation bubble was revealed by thermal and flow visualization.

Hippensteele, S. A.; Russell, L. M.; Torres, F. J.

1985-01-01

369

Practical considerations for maximizing heat production in a novel thermobrachytherapy seed prototype  

PubMed Central

Purpose: A combination of hyperthermia and radiation in the treatment of cancer has been proven to provide better tumor control than radiation administered as a monomodality, without an increase in complications or serious toxicities. Moreover, concurrent administration of hyperthermia and radiation displays synergistic enhancement, resulting in greater tumor cell killing than hyperthermia and radiation delivered separately. The authors have designed a new thermobrachytherapy (TB) seed, which serves as a source of both radiation and heat for concurrent brachytherapy and hyperthermia treatments when implanted in solid tumors. This innovative seed, similar in size and geometry to conventional seeds, will have self-regulating thermal properties. Methods: The new seed's geometry is based on the standard BEST Model 2301 125I seed, resulting in very similar dosimetric properties. The TB seed generates heat when placed in an oscillating magnetic field via induction heating of a ferromagnetic Ni–Cu alloy core that replaces the tungsten radiographic marker of the standard Model 2301. The alloy composition is selected to undergo a Curie transition near 50?°C, drastically decreasing power production at higher temperatures and providing for temperature self-regulation. Here, the authors present experimental studies of the magnetic properties of Ni–Cu alloy material, the visibility of TB seeds in radiographic imaging, and the ability of seed prototypes to uniformly heat tissue to a desirable temperature. Moreover, analyses are presented of magnetic shielding and thermal expansion of the TB seed, as well as matching of radiation dose to temperature distributions for a short interseed distance in a given treatment volume. Results: Annealing the Ni–Cu alloy has a significant effect on its magnetization properties, increasing the sharpness of the Curie transition. The TB seed preserves the radiographic properties of the BEST 2301 seed in both plain x rays and CT images, and a preliminary experiment demonstrates thermal self-regulation and adequate heating of a tissue-mimicking phantom by seed prototypes. The effect of self-shielding of the seed against the external magnetic field is small, and only minor thermal stress is induced in heating of the seeds from room temperature to well above the seed operating temperature. With proper selection of magnetic field parameters, the thermal dose distribution of an arrangement of TB and hyperthermia-only seeds may be made to match with its radiation dose distribution. Conclusions: The presented analyses address several practical considerations for manufacturing of the proposed TB seeds and identify critical issues for the prototype implementation. The authors’ preliminary experiments demonstrate close agreement with the modeling results, confirming the feasibility of combining sources of heat and radiation into a single thermobrachytherapy seed. PMID:24506651

Gautam, Bhoj; Warrell, Gregory; Shvydka, Diana; Subramanian, Manny; Ishmael Parsai, E.

2014-01-01

370

Practical considerations for maximizing heat production in a novel thermobrachytherapy seed prototype  

SciTech Connect

Purpose: A combination of hyperthermia and radiation in the treatment of cancer has been proven to provide better tumor control than radiation administered as a monomodality, without an increase in complications or serious toxicities. Moreover, concurrent administration of hyperthermia and radiation displays synergistic enhancement, resulting in greater tumor cell killing than hyperthermia and radiation delivered separately. The authors have designed a new thermobrachytherapy (TB) seed, which serves as a source of both radiation and heat for concurrent brachytherapy and hyperthermia treatments when implanted in solid tumors. This innovative seed, similar in size and geometry to conventional seeds, will have self-regulating thermal properties. Methods: The new seed's geometry is based on the standard BEST Model 2301{sup 125}I seed, resulting in very similar dosimetric properties. The TB seed generates heat when placed in an oscillating magnetic field via induction heating of a ferromagnetic Ni–Cu alloy core that replaces the tungsten radiographic marker of the standard Model 2301. The alloy composition is selected to undergo a Curie transition near 50?°C, drastically decreasing power production at higher temperatures and providing for temperature self-regulation. Here, the authors present experimental studies of the magnetic properties of Ni–Cu alloy material, the visibility of TB seeds in radiographic imaging, and the ability of seed prototypes to uniformly heat tissue to a desirable temperature. Moreover, analyses are presented of magnetic shielding and thermal expansion of the TB seed, as well as matching of radiation dose to temperature distributions for a short interseed distance in a given treatment volume. Results: Annealing the Ni–Cu alloy has a significant effect on its magnetization properties, increasing the sharpness of the Curie transition. The TB seed preserves the radiographic properties of the BEST 2301 seed in both plain x rays and CT images, and a preliminary experiment demonstrates thermal self-regulation and adequate heating of a tissue-mimicking phantom by seed prototypes. The effect of self-shielding of the seed against the external magnetic field is small, and only minor thermal stress is induced in heating of the seeds from room temperature to well above the seed operating temperature. With proper selection of magnetic field parameters, the thermal dose distribution of an arrangement of TB and hyperthermia-only seeds may be made to match with its radiation dose distribution. Conclusions: The presented analyses address several practical considerations for manufacturing of the proposed TB seeds and identify critical issues for the prototype implementation. The authors’ preliminary experiments demonstrate close agreement with the modeling results, confirming the feasibility of combining sources of heat and radiation into a single thermobrachytherapy seed.

Gautam, Bhoj; Warrell, Gregory; Shvydka, Diana; Ishmael Parsai, E., E-mail: e.parsai@utoledo.edu [University of Toledo Medical Center, 3000 Arlington Avenue, MS1151, Toledo, Ohio 43614 (United States); Subramanian, Manny [BEST Medical International, Inc., 7643 Fullerton Road, Springfield, Virginia 22153 (United States)] [BEST Medical International, Inc., 7643 Fullerton Road, Springfield, Virginia 22153 (United States)

2014-02-15

371

MODIS LAI and FPAR Product on Global, Regional and Local Scales  

NASA Astrophysics Data System (ADS)

An algorithm based on physics of radiative transfer in vegetation canopies for the retrieval of vegetation green leaf area index (LAI) and fraction of absorbed photosynthetically active radiation (FPAR) from MODIS surface reflectance data was developed, prototyped and is in operational production at NASA computing facilities since June 2000. This presentation is focused on the analysis of the of the LAI and FPAR retrievals as a function of time and spatial scale as detailed below. First theme covers analysis of the global MODIS LAI and FPAR products from July 2000 to December 2002, collections 1 and 3. About 70% of the total retrievals are obtained with the main radiative transfer based algorithm. Temporal compositing from 8-day to monthly further increases the frequency of main algorithm retrievals. The retrieved LAI and FPAR fields display expected features when analyzed by biomes and latitudes. The main algorithm fails as expected when input surface reflectance data have high uncertainties, especially under snow and cloud conditions. The analysis presented here reinforces the need for examining product quality flags accompanying the LAI and FPAR product before using these products in application studies. Second theme covers analysis of the LAI product at regional and local scales. We highlight the statistical nature of MODIS LAI and FPAR products arising from the relation between uncertainties in algorithm inputs and outputs, using Collection 3 MODIS LAI product. Two random variables impact the quality of retrieved LAI and FPAR fields at local scale- uncertainties in biome classification and surface reflectance measurements. To decrease impact of input uncertainties, averaging of LAI and FPAR product over an extended area is required to accumulate a sufficient number of pixels with high quality input. Further improvements in LAI and FPAR retrieval coverage and quality will require a better consistency between observed and simulated reflectances in spectral space.

Knyazikhin, Y.; Yang, W.; Dong, H.; Bin, T.; Shabanov, N.; Myneni, R.

2003-12-01

372

Modelling Hydraulic and Thermal Responses in a Benchmark for Deep Geothermal Heat Production  

NASA Astrophysics Data System (ADS)

Geothermal heat production from deep reservoirs (5000-7000 m) is currently examined within the collaborative research program "Geothermal Energy and High-Performance Drilling" (gebo), funded by the Ministry of Science and Culture of Lower Saxony (Germany) and Baker Hughes. The projects concern exploration and characterization of geothermal reservoirs as well as production. They are gathered in the four major topic fields: geosystem, drilling, materials, technical system. We present modelling of a benchmark set-up concerning the geothermal production itself. The benchmark model "Horstberg" was originally created by J. Löhken and is based on geological data, concerning the Horstberg site in Lower Saxony. The model region consists of a cube with a side length of 5 km, in which 13 geological layers are included. A fault zone splits the region into two parts with shifted layering. A well is implemented, reaching from the top to an optional depth crossing all layers including the fault zone. The original geological model was rebuilt and improved in COMSOL Multiphysics Version 4.2a. The heterogeneous and detailed configuration makes the model interesting for benchmarking hydrogeological and geothermal applications. It is possible to inject and pump at any level in the well and to study the hydraulic and thermal responses of the system. The hydraulic and thermal parameters can be varied, and groundwater flow can be introduced. Moreover, it is also possible to examine structural mechanical responses to changes in the stress field (which is not further examined here). The main purpose of the presented study is to examine the dynamical flow characteristics of a hydraulic high conductive zone (Detfurth) in connection to a high conductive fault. One example is the fluid injection in the Detfurth zone and production in the fault. The high conductive domains can provide a hydraulic connection between the well screens and the initiated flow circuit could be used for geothermal heat production. The dependence of the flow regime and heat production on parameters like pumping rate, aquifer velocity and well position is demonstrated. Acknowledgements: gebo

Holzbecher, E.; Oberdorfer, P.

2012-04-01

373

Compilation of Data on Radionuclide Data for Specific Activity, Specific Heat and Fission Product Yields  

SciTech Connect

This compilation was undertaken to update the data used in calculation of curie and heat loadings of waste containers in the Solid Waste Management Facility. The data has broad general use and has been cross-checked extensively in order to be of use in the Materials Accountability arena. The fission product cross-sections have been included because they are of use in the Environmental Remediation and Waste Management areas where radionuclides which are not readily detectable need to be calculated from the relative fission yields and material dispersion data.

Gibbs, A.; Thomason, R.S.

2000-09-05

374

Developing natural convection in a fluid layer with localized heating and large viscosity variation  

SciTech Connect

Numerical simulations and laboratory experiments are used to elucidate aspects of transient natural convection in a magma chamber. The magma chamber is modeled as a horizontal fluid layer confined within an enclosure of square planform and heated from below by a strip heater centered on the lower boundary of the enclosure. The width of the strip heater and the depth of the fluid layer are one-fourth of the layer width. Corn syrup is used as the working fluid in order to approximate the large viscosity variation with temperature and the large Prandtl number typical of magma. The quiescent, uniform, fluid layer is subjected to instantaneous heating from the strip heater producing a transient flow which is dominated by two counter-rotating convective cells. Experimentally determined characteristics of the developing flow are compared with numerical simulations carried out with a finite element computer program. The results of numerical simulations are in essential agreement with experimental data. Differences between the numerical simulations and experimental measurements are conjectured to result from non-ideal effects present in the experiment which are difficult to represent accurately in a numerical simulation.

Hickox, C.E.; Chu, Tze Yao.

1991-01-01

375

Biohydrogen production from CO-rich syngas via a locally isolated Rhodopseudomonas palustris PT.  

PubMed

Biohydrogen production through water–gas shift (WGS) reaction by a biocatalyst was conducted in batch fermentation. The isolated photosynthetic bacterium Rhodopseudomonas palustris PT was able to utilize carbon monoxide and simultaneously produce hydrogen. Light exposure was provided as an indispensable requirement for the first stage of bacterial growth, but throughout the hydrogen production stage, the energy requirement was met through the WGS reaction. At ambient pressure and temperature, the effect of various sodium acetate concentrations in presence of CO-rich syngas on cell growth, carbon monoxide consumption, and biohydrogen production was also investigated. Maximal efficiency of hydrogen production in response to carbon monoxide consumption was recorded at 86 % and the highest concentration of hydrogen at 33.5 mmol/l was achieved with sodium acetate concentration of 1.5 g/l. The obtained results proved that the local isolate; R. palustris PT, was able to utilize CO-rich syngas and generate biohydrogen via WGS reaction. PMID:24078148

Pakpour, Fatemeh; Najafpour, Ghasem; Tabatabaei, Meisam; Tohidfar, Masoud; Younesi, Habiboallah

2014-05-01

376

Carbonaceous material for production of hydrogen from low heating value fuel gases  

DOEpatents

A process for the catalytic production of hydrogen, from a wide variety of low heating value fuel gases containing carbon monoxide, comprises circulating a carbonaceous material between two reactors--a carbon deposition reactor and a steaming reactor. In the carbon deposition reactor, carbon monoxide is removed from a fuel gas and is deposited on the carbonaceous material as an active carbon. In the steaming reactor, the reactive carbon reacts with steam to give hydrogen and carbon dioxide. The carbonaceous material contains a metal component comprising from about 75% to about 95% cobalt, from about 5% to about 15% iron, and up to about 10% chromium, and is effective in suppressing the production of methane in the steaming reactor.

Koutsoukos, Elias P. (Los Angeles, CA)

1989-01-01

377

ASPEN+ and economic modeling of equine waste utilization for localized hot water heating via fast pyrolysis  

Technology Transfer Automated Retrieval System (TEKTRAN)

ASPEN Plus based simulation models have been developed to design a pyrolysis process for the on-site production and utilization of pyrolysis oil from equine waste at the Equine Rehabilitation Center at Morrisville State College (MSC). The results indicate that utilization of all available Equine Reh...

378

Multi-scale modeling of localized heating caused by ion bombardment  

NASA Astrophysics Data System (ADS)

We have developed a multiscale modeling algorithm to incorporate both a Monte Carlo (MC) ion irradiation simulator and finite element analysis to simulate ion beam heating. The spatial distribution of displacements from the MC code was input into a 3-D FEA code to predict the temperature evolution upon ion bombardment. In order to simulate the flux effect, ions were introduced stochastically. We discuss the necessity to use both grid refinement and grid coarsening techniques to make such modeling possible, thus providing a basis to evaluate the impact on the microstructure of the substrate. The aforementioned approach was applied for the case of a 16 A cm -2 beam of 6 keV Ga + ions to simulate FIB sample sectioning and thinning in a Si substrate.

Myers, Michael T.; Sencer, Bulent H.; Shao, Lin

2012-02-01

379

Model predictive control of a combined heat and power plant using local linear models  

SciTech Connect

Model predictive control has been applied to control of a combined heat and power plant. One of the main features of this plant is that it exhibits nonlinear process behavior due to large throughput swings. In this application, the operating window of the plant has been divided into a number of smaller windows in which the nonlinear process behavior has been approximated by linear behavior. For each operating window, linear step weight models were developed from a detailed nonlinear first principles model, and the model prediction is calculated based on interpolation between these linear models. The model output at each operating point can then be calculated from four basic linear models, and the required control action can subsequently be calculated with the standard model predictive control approach using quadratic programming.

Kikstra, J.F. [Delft Univ. of Technology (Netherlands). Faculty of Mechanical Engineering; Roffel, B. [Univ. of Twente, AE Enschede (Netherlands). Faculty of Chemical Engineering; Schoen, P. [Stork Engineers and Contractors, Amsterdam (Netherlands)

1998-10-01

380

The product of hedgehog autoproteolytic cleavage active in local and long-range signalling  

Microsoft Academic Search

THE secreted protein products of the hedgehog (hh) gene family are associated with local and long-range signalling activities that are responsible for developmental patterning in multiple systems, including Drosophila embryonic and larval tissues1-8 and vertebrate neural tube, limbs and somites9-15. In a process that is critical for full biological activity, the hedgehog protein (Hh) undergoes autoproteolysis to generate two biochemically

Jeffery A. Porter; Doris P. von Kessler; Stephen C. Ekker; Keith E. Young; John J. Lee; Kevin Moses; Philip A. Beachy

1995-01-01

381

Cellular Localization of the Multidrug-Resistance Gene Product P-glycoprotein in Normal Human Tissues  

Microsoft Academic Search

Monoclonal antibody MRK16 was used to determine the location of P-glycoprotein, the product of the multidrug-resistance gene (MDR1), in normal human tissues. The protein was found to be concentrated in a small number of specific sites. Most tissues examined revealed very little P-glycoprotein. However, certain cell types in liver, pancreas, kidney, colon, and jejunum showed specific localization of P-glycoprotein. In

Franz Thiebaut; Takashi Tsuruo; Hirofumi Hamada; Michael M. Gottesman; Ira Pastan; Mark C. Willingham

1987-01-01

382

EFFECTS OF LOCALIZED AQUIFER BOILING ON FLUID PRODUCTION AT CERRO PRIETO.  

USGS Publications Warehouse

Localized aquifer boiling in the shallow two-phase reservoir of Cerro Prieto has produced excess steam and increased electrical output. Unfortunately it has also caused near-well mineral deposition that has decreased permeability and fluid flow. Inflow of cold water has limited the extent of aquifer boiling and permeability loss. The deeper reservoir at Cerro Prieto may need injection of cold water to decrease boiling and prevent loss of production. Refs.

Truesdell, Alfred H.; D'Amore, Franco; Nieva, David

1984-01-01

383

Bending Properties of Locally Laser Heat Treated AA2024-T3 Aluminium Alloy  

NASA Astrophysics Data System (ADS)

The bending properties of AA2024-T3 aluminium alloy after localized laser assisted softening have been studied and compared to untreated material. Single and multi-path laser scanning strategies are applied for achieving a predictable and minimized springback. Process parameters for softening have been chosen based on FE modeling. In order to investigate the softening, and to characterize the size of this softened region, hardness measurements were carried out. Using a triple scanning path strategy springback was reduced by about 43% without changing the bending radius.

Mohammadi, Amirahmad; Vanhove, Hans; Van Bael, Albert; Duflou, Joost R.

384

Changes in the localization and levels of starch and lipids in cambium and phloem during cambial reactivation by artificial heating of main stems of Cryptomeria japonica trees  

PubMed Central

Background and Aims Cambial reactivation in trees occurs from late winter to early spring when photosynthesis is minimal or almost non-existent. Reserve materials might be important for wood formation in trees. The localization and approximate levels of starch and lipids (as droplets) and number of starch granules in cambium and phloem were examined from cambial dormancy to the start of xylem differentiation in locally heated stems of Cryptomeria japonica trees in winter. Methods Electric heating tape was wrapped on one side of the stem of Cryptomeria japonica trees at breast height in winter. The localization and approximate levels of starch and lipids (as droplets) and number of starch granules were determined by image analysis of optical digital images obtained by confocal laser scanning microscopy. Key Results Localized heating induced earlier cambial reactivation and xylem differentiation in stems of Cryptomeria japonica, as compared with non-heated stems. There were clear changes in the respective localizations and levels of starch and lipids (as droplets) determined in terms of relative areas on images, from cambial dormancy to the start of xylem differentiation in heated stems. In heated stems, the levels and number of starch granules fell from cambial reactivation to the start of xylem differentiation. There was a significant decrease in the relative area occupied by lipid droplets in the cambium from cambial reactivation to the start of xylem differentiation in heated stems. Conclusions The results showed clearly that the levels and number of storage starch granules in cambium and phloem cells and levels of lipids (as droplets) in the cambium decreased from cambial reactivation to the start of xylem differentiation in heated stems during the winter. The observations suggest that starch and lipid droplets might be needed as sources of energy for the initiation of cambial cell division and the differentiation of xylem in Cryptomeria japonica. PMID:21037242

Begum, Shahanara; Nakaba, Satoshi; Oribe, Yuichiro; Kubo, Takafumi; Funada, Ryo

2010-01-01

385

Gas production and transport during bench-scale electrical resistance heating of water and trichloroethene.  

PubMed

The effective remediation of chlorinated solvent source zones using in situ thermal treatment requires successful capture of gas that is produced. Replicate electrical resistance heating experiments were performed in a thin bench-scale apparatus, where water was boiled and pooled dense non-aqueous phase liquid (DNAPL) trichloroethene (TCE) and water were co-boiled in unconsolidated silica sand. Quantitative light transmission visualization was used to assess gas production and transport mechanisms. In the water boiling experiments, nucleation, growth and coalescence of the gas phase into connected channels were observed at critical gas saturations of Sgc=0.233±0.017, which allowed for continuous gas transport out of the sand. In experiments containing a colder region above a target heated zone, condensation prevented the formation of steam channels and discrete gas clusters that mobilized into colder regions were trapped soon after discontinuous transport began. In the TCE-water experiments, co-boiling at immiscible fluid interfaces resulted in discontinuous gas transport above the DNAPL pool. Redistribution of DNAPL was also observed above the pool and at the edge of the vapor front that propagated upwards through colder regions. These results suggest that the subsurface should be heated to water boiling temperatures to facilitate gas transport from specific locations of DNAPL to extraction points and reduce the potential for DNAPL redistribution. Decreases in electric current were observed at the onset of gas phase production, which suggests that coupled electrical current and temperature measurements may provide a reliable metric to assess gas phase development. PMID:25084057

Hegele, P R; Mumford, K G

2014-09-01

386

Effects of steam pretreatment and co-production with ethanol on the energy efficiency and process economics of combined biogas, heat and electricity production from industrial hemp  

PubMed Central

Background The study presented here has used the commercial flow sheeting program Aspen Plus™ to evaluate techno-economic aspects of large-scale hemp-based processes for producing transportation fuels. The co-production of biogas, district heat and power from chopped and steam-pretreated hemp, and the co-production of ethanol, biogas, heat and power from steam-pretreated hemp were analysed. The analyses include assessments of heat demand, energy efficiency and process economics in terms of annual cash flows and minimum biogas and ethanol selling prices (MBSP and MESP). Results Producing biogas, heat and power from chopped hemp has the highest overall energy efficiency, 84% of the theoretical maximum (based on lower heating values), providing that the maximum capacity of district heat is delivered. The combined production of ethanol, biogas, heat and power has the highest energy efficiency (49%) if district heat is not produced. Neither the inclusion of steam pretreatment nor co-production with ethanol has a large impact on the MBSP. Ethanol is more expensive to produce than biogas is, but this is compensated for by its higher market price. None of the scenarios examined are economically viable, since the MBSP (EUR 103–128 per MWh) is higher than the market price of biogas (EUR 67 per MWh). The largest contribution to the cost is the cost of feedstock. Decreasing the retention time in the biogas process for low solids streams by partly replacing continuous stirred tank reactors by high-rate bioreactors decreases the MBSP. Also, recycling part of the liquid from the effluent from anaerobic digestion decreases the MBSP. The production and prices of methane and ethanol influence the process economics more than the production and prices of electricity and district heat. Conclusions To reduce the production cost of ethanol and biogas from biomass, the use of feedstocks that are cheaper than hemp, give higher output of ethanol and biogas, or combined production with higher value products are primarily suggested. Further, practical investigations on increased substrate concentration in biogas and ethanol production, recycling of the liquid in anaerobic digestion and separation of low solids flows into solid and a liquid fraction for improved reactor applications deserves further attention. PMID:23607263

2013-01-01

387

Human hnRNP Q re-localizes to cytoplasmic granules upon PMA, thapsigargin, arsenite and heat-shock treatments  

SciTech Connect

Eukaryotic gene expression is regulated on different levels ranging from pre-mRNA processing to translation. One of the most characterized families of RNA-binding proteins is the group of hnRNPs: heterogenous nuclear ribonucleoproteins. Members of this protein family play important roles in gene expression control and mRNAs metabolism. In the cytoplasm, several hnRNPs proteins are involved in RNA-related processes and they can be frequently found in two specialized structures, known as GW-bodies (GWbs), previously known as processing bodies: PBs, and stress granules, which may be formed in response to specific stimuli. GWbs have been early reported to be involved in the mRNA decay process, acting as a site of mRNA degradation. In a similar way, stress granules (SGs) have been described as cytoplasmic aggregates, which contain accumulated mRNAs in cells under stress conditions and present reduced or inhibited translation. Here, we characterized the hnRNP Q localization after different stress conditions. hnRNP Q is a predominantly nuclear protein that exhibits a modular organization and several RNA-related functions. Our data suggest that the nuclear localization of hnRNP Q might be modified after different treatments, such as: PMA, thapsigargin, arsenite and heat shock. Under different stress conditions, hnRNP Q can fully co-localize with the endoplasmatic reticulum specific chaperone, BiP. However, under stress, this protein only co-localizes partially with the proteins: GW182 - GWbs marker protein and TIA-1 stress granule component.

Quaresma, Alexandre J.C. [Brazilian Synchrotron Light Laboratory - LNLS, 13083-970, Campinas, SP (Brazil); Bressan, G.C. [Brazilian Synchrotron Light Laboratory - LNLS, 13083-970, Campinas, SP (Brazil); Institute of Biology, University of Campinas - UNICAMP, 13083-970, Campinas, SP (Brazil); Gava, L.M. [Institute of Biology, University of Campinas - UNICAMP, 13083-970, Campinas, SP (Brazil); Institute of Chemistry, University of Campinas, CEP 13083-970, Campinas, SP (Brazil); Lanza, D.C.F. [Brazilian Synchrotron Light Laboratory - LNLS, 13083-970, Campinas, SP (Brazil); Institute of Biology, University of Campinas - UNICAMP, 13083-970, Campinas, SP (Brazil); Ramos, C.H.I [Institute of Chemistry, University of Campinas, CEP 13083-970, Campinas, SP (Brazil); Kobarg, Joerg [Brazilian Synchrotron Light Laboratory - LNLS, 13083-970, Campinas, SP (Brazil); Institute of Biology, University of Campinas - UNICAMP, 13083-970, Campinas, SP (Brazil)], E-mail: jkobarg@lnls.br

2009-04-01

388

Vertical Profiles of Latent Heat Release over the Global Tropics using TRMM Rainfall Products from December 1997 to November 2002  

NASA Technical Reports Server (NTRS)

NASA Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) derived rainfall information will be used to estimate the four-dimensional structure of global monthly latent heating and rainfall profiles over the global tropics from December 1997 to November 2000. Rainfall, latent heating and radar reflectivity structures between El Nino (DJF 1997-98) and La Nina (DJF 1998-99) will be examined and compared. The seasonal variation of heating over various geographic locations (i.e., oceanic vs continental, Indian ocean vs west Pacific, Africa vs. S. America ) will also be analyzed. In addition, the relationship between rainfall, latent heating (maximum heating level), radar reflectivity and SST is examined and will be presented in the meeting. The impact of random error and bias in stratiform percentage estimates from PR on latent heating profiles is studied and will also be presented in the meeting. The Goddard Cumulus Ensemble Model is being used to simulate various mesoscale convective systems that developed in different geographic locations. Specifically, the model estimated rainfall, radar reflectivity and latent heating profiles will be compared to observational data collected from TRMM field campaigns over the South China Sea in 1998 (SCSMEX), Brazil in 1999 (TRMM-LBA), and the central Pacific in 1999 (KWAJEX). Sounding diagnosed heating budgets and radar reflectivity from these experiments can provide the means to validate (heating product) as well as improve the GCE model. Review of other latent heating algorithms will be discussed in the workshop.

Tao, W.-K.; Lang, S.; Simpson, J.; Meneghini, R.; Halverson, J.; Johnson, R.; Adler, R.

2003-01-01

389

A gyrokinetic one-dimensional scrape-off layer model of an edge-localized mode heat pulse  

NASA Astrophysics Data System (ADS)

An electrostatic gyrokinetic-based model is applied to simulate parallel plasma transport in the scrape-off layer to a divertor plate. The authors focus on a test problem that has been studied previously, using parameters chosen to model a heat pulse driven by an edge-localized mode in JET. Previous work has used direct particle-in-cell equations with full dynamics, or Vlasov or fluid equations with only parallel dynamics. With the use of the gyrokinetic quasineutrality equation and logical sheath boundary conditions, spatial and temporal resolution requirements are no longer set by the electron Debye length and plasma frequency, respectively. This test problem also helps illustrate some of the physics contained in the Hamiltonian form of the gyrokinetic equations and some of the numerical challenges in developing an edge gyrokinetic code.

Shi, E. L.; Hakim, A. H.; Hammett, G. W.

2015-02-01

390

Finite Volume schemes on unstructured grids for non-local models: Application to the simulation of heat transport in plasmas  

SciTech Connect

In the so-called Spitzer-Haerm regime, equations of plasma physics reduce to a nonlinear parabolic equation for the electronic temperature. Coming back to the derivation of this limiting equation through hydrodynamic regime arguments, one is led to construct a hierarchy of models where the heat fluxes are defined through a non-local relation which can be reinterpreted as well by introducing coupled diffusion equations. We address the question of designing numerical methods to simulate these equations. The basic requirement for the scheme is to be asymptotically consistent with the Spitzer-Haerm regime. Furthermore, the constraints of physically realistic simulations make the use of unstructured meshes unavoidable. We develop a Finite Volume scheme, based on Vertex-Based discretization, which reaches these objectives. We discuss on numerical grounds the efficiency of the method, and the ability of the generalized models in capturing relevant phenomena missed by the asymptotic problem.

Goudon, Thierry, E-mail: thierry.goudon@inria.fr [Team COFFEE, INRIA Sophia Antipolis Mediterranee (France) [Team COFFEE, INRIA Sophia Antipolis Mediterranee (France); Labo. J.A. Dieudonne CNRS and Univ. Nice-Sophia Antipolis (UMR 7351), Parc Valrose, 06108 Nice cedex 02 (France); Parisot, Martin, E-mail: martin.parisot@gmail.com [Project-Team SIMPAF, INRIA Lille Nord Europe, Park Plazza, 40 avenue Halley, F-59650 Villeneuve d'Ascq cedex (France)] [Project-Team SIMPAF, INRIA Lille Nord Europe, Park Plazza, 40 avenue Halley, F-59650 Villeneuve d'Ascq cedex (France)

2012-10-15

391

Evidence of locally enhanced target heating due to instabilities of counter-streaming fast electron beams  

NASA Astrophysics Data System (ADS)

The high-current fast electron beams generated in high-intensity laser-solid interactions require the onset of a balancing return current in order to propagate in the target material. Such a system of counter-streaming electron currents is unstable to a variety of instabilities such as the current-filamentation instability and the two-stream instability. An experimental study aimed at investigating the role of instabilities in a system of symmetrical counter-propagating fast electron beams is presented here for the first time. The fast electron beams are generated by double-sided laser-irradiation of a layered target foil at laser intensities above 1019 W/cm2. High-resolution X-ray spectroscopy of the emission from the central Ti layer shows that locally enhanced energy deposition is indeed achieved in the case of counter-propagating fast electron beams.

Koester, Petra; Booth, Nicola; Cecchetti, Carlo A.; Chen, Hui; Evans, Roger G.; Gregori, Gianluca; Labate, Luca; Levato, Tadzio; Li, Bin; Makita, Mikako; Mithen, James; Murphy, Christopher D.; Notley, Margaret; Pattathil, Rajeev; Riley, David; Woolsey, Nigel; Gizzi, Leonida A.

2015-02-01

392

Effect of gold nanoparticles in the local heating of skin tumors induced by phototherapy  

NASA Astrophysics Data System (ADS)

During optical therapies, several types of interaction between the optical radiation and the target tissue can occur. The application of different power densities and the variation of the exposure time can cause from photochemical reactions to photodisruption. Photothermal therapy (PTT) is based in the thermal interactions, where the biological injury is provoked by a given increase of their temperature during the exposition to the optical source. Another treatment option very extended in several clinical fields due to its promising results is Photodynamic Therapy. This treatment modality is based in photochemical reactions where it is also required oxygen and the administration of a photosensitive substance known as photosensitizer. The use of nanotechnology in optical therapeutic techniques, constitutes a novel promising treatment strategy. Specifically, gold nanoparticles can improve different issues related to the transport of photosensitizers or the light energy absorption and the subsequent heat generation. This work focuses in the effects that can produce the use of gold nanoparticles in Photothermal and Photodynamic Therapies applied to skin diseases commonly treated by means of these techniques. We present a thermal model that permits to calculate the temperature distribution in different kinds of pathological dermatological tissues depending on the optical power provided by the optical source. The results obtained permit to compare the thermal injury produced depending on not only the provided power but also the type of pathology and the incorporation or not of gold nanoparticles in the target tissue.

Salas-García, I.; Fanjul-Vélez, F.; Ortega-Quijano, N.; Lavín-Castanedo, A.; Mingo-Ortega, P.; López-Escobar, M.; Arce-Diego, J. L.

2011-07-01

393

Heat-killed Lactobacillus plantarum L-137 suppresses naturally fed antigen–specific IgE production by stimulation of IL12 production in mice  

Microsoft Academic Search

Background: Food allergy is caused by production of IgE against dietary antigen induced by TH2 response. IL-12 inhibits TH2 responses and strongly suppresses IgE production. We have recently established a murine model for IgE production with a predominant TH2 response induced by feeding antigen.Objective: We here show a suppressive effect of heat-killed Lactobacillus plantarum L-137, a potent inducer of IL-12,

Shinji Murosaki; Yoshihiro Yamamoto; Kazue Ito; Takeaki Inokuchi; Hiroaki Kusaka; Hitoshi Ikeda; Yasunobu Yoshikai

1998-01-01

394

On the mechanism of salt tolerance. Production of glycerol and heat during growth of Debaryomyces hansenii.  

PubMed

As glycerol was suggested as an osmotic agent in the salt tolerant Debaryomyces hansenii the concentrations of total, intracellular, and extracellular glycerol produced by this yeast was followed during growth in 4 mM, 0.68 M, and 2.7 M NaCl media. The total amount of glycerol was not directly proportional to biomass production but to the cultural salinity with maximum concentrations just prior to or at the beginning of the stationary phase. In all cultures the cells lost some glycerol to the media, at 2.7 M NaCl the extracellular glycerol even amounted maximally to 80% of the total. A distinct maximum of intracellular glycerol, related to dry weight or cell number, appeared during the log phase at all NaCl concentrations. As the intracellular calculated glycerol concentrations amounted to 0.2 M, 0.8 M, and 2.6 M in late log phase cells at 4mM, 0.68 M, and 2.7 M NaCl, respectively, whereas the corresponding analysed values for the glycerol concentrations of the media were 0.7 mM, 2.5 mM, and 3.0 mM, glycerol contributes to the osmotic balance of the cells. During the course of growth all cultures showed a decreasing heat production related to cell substance produced, most pronounced at 2.7 M NaCl. At 2.7 M NaCl the total heat production amounted to--1690 kJ per mole glucose consumed in contrast to--1200 and--1130 kJ at 4 mM and 0.68 M NaCl, respectively. The Ym-values were of an inverse order, being 129, 120, and 93 at 4 mM, 0.68 M, and 2.7 M NaCl respectively. PMID:1015945

Gustafsson, L; Norkrans, B

1976-11-01

395

Biobutanol production by a new local isolate of Clostridium acetobutylicum YM1  

NASA Astrophysics Data System (ADS)

Increasing demand of energy and awareness about environmental pollution has led to increase interest in alternative, clean and renewable energy sources. Biobutanol is considered as the candidate liquid biofuel to replace gasoline. In this study, the capability of a newly isolated strain of local Clostridium acetobutylicum YM1 was tested to produce biobutanol in batch fermentation. Various culture conditions including glucose concentration, initial pH, incubation temperature and inoculum size were investigated for their effects on production of biobutanol using strain YM1. The results showed that the optimal biobutanol production was obtained at glucose concentration 50 g/L, initial pH 6.2, temperature 30°C and inoculum size 10%. These results show that C. acetobutylicum YM1 as a mesophilic bacterium is a potential candidate for biobutanol production.

Al-Shorgani, Najeeb Kaid; Tibin, El Mubarak; Kalil, Mohd Sahaid; Yusoff, Wan Mohtar Wan; Hamid, Aidil Abdul

2014-09-01

396

Processes governing phytoplankton blooms in estuaries. I: The local production-loss balance  

USGS Publications Warehouse

The formation and spatial distribution of phytoplankton blooms in estuaries are controlled by (1) local mechanisms, which determine the production-loss balance for a water column at a particular spatial location (i.e. control if a bloom is possible), and (2) transport-related mechanisms, which govern biomass distribution (i.e. control if and where a bloom actually occurs). In this study, the first of a 2-paper series, we use a depth-averaged numerical model as a theoretical tool to describe how interacting local conditions (water column height, light availability, benthic grazing) influence the local balance between phytoplankton sources and sinks. We also explore trends in the spatial variability of the production-loss balance across the topographic gradients between deep channels and lateral shoals which are characteristic of shallow estuaries. For example, under conditions of high turbidity and slow benthic grazing the highest rates of phytoplankton population growth are found in the shallowest regions. On the other hand, with low turbidity and rapid benthic grazing the highest growth rates occur in the deeper areas. We also explore the effects of semidiurnal tidal variation in water column height, as well as spring-neap variability. Local population growth in the shallowest regions is very sensitive to tidal-scale shallowing and deepening of the water column, especially in the presence of benthic grazing. A spring-neap signal in population growth rate is also prominent in the shallow areas. Population growth in deeper regions is less sensitive to temporal variations in tidal elevation. These results show that both shallow and deep regions of estuaries can act as sources or sinks for phytoplankton biomass, depending on the local conditions of mean water column height, tidal amplitude, light-limited growth rate, and consumption by grazers.

Lucas, L.V.; Koseff, J.R.; Cloern, J.E.; Monismith, S.G.; Thompson, J.K.

1999-01-01

397

24 CFR 200.950 - Building product standards and certification program for solar water heating system.  

Code of Federal Regulations, 2011 CFR

...standards and certification program for solar water heating system. 200.950 Section...standards and certification program for solar water heating system. (a) Applicable standards. (1) All solar water heating systems shall be...

2011-04-01

398

24 CFR 200.950 - Building product standards and certification program for solar water heating system.  

Code of Federal Regulations, 2012 CFR

...standards and certification program for solar water heating system. 200.950 Section...standards and certification program for solar water heating system. (a) Applicable standards. (1) All solar water heating systems shall be...

2012-04-01

399

24 CFR 200.950 - Building product standards and certification program for solar water heating system.  

Code of Federal Regulations, 2014 CFR

...standards and certification program for solar water heating system. 200.950 Section...standards and certification program for solar water heating system. (a) Applicable standards. (1) All solar water heating systems shall be...

2014-04-01

400

24 CFR 200.950 - Building product standards and certification program for solar water heating system.  

Code of Federal Regulations, 2013 CFR

...standards and certification program for solar water heating system. 200.950 Section...standards and certification program for solar water heating system. (a) Applicable standards. (1) All solar water heating systems shall be...

2013-04-01

401

Xylanase production with xylan rich lignocellulosic wastes by a local soil isolate of Trichoderma viride  

PubMed Central

In the present study, cultural and nutritional conditions for enhanced production of xylanase by a local soil isolate of Trichoderma viride, using various lignocellulosic substrates in submerged culture fermentation have been optimized. Of the lignocellulosics used, maize straw was the best inducer followed by jowar straw for xylanase production. The highest activity achieved was between 14 to 17 days of fermentation. A continuous increase in xylanase production was observed with increasing level of lignocellulosics in the medium and highest activity was observed with maize straw at 5% level. Xylanase production with higher levels of lignocellulosics (3 to 5%) of maize, jowar and barseem was found to be higher as compared to that with commercial xylan as carbon source. Sodium nitrate was the best nitrogen source among the six sources used. Maximum xylanase production was achieved with initial medium pH of 3.5–4.0 and incubation temperature of 25ºC.The enzyme preparation was effective in bringing about saccharification of different lignocellulosics. The xylanase production could be further improved by using alkali treated straw as carbon source. PMID:24031262

Goyal, Meenakshi; Kalra, K.L.; Sareen, V.K.; Soni, G.

2008-01-01

402

Determination of mass and heat transfer parameters during freeze-drying cycles of pharmaceutical products.  

PubMed

The principal aim of this study was to evaluate the water vapour mass transfer resistance of the dried layer and the vial heat transfer coefficient values of a pharmaceutical product during the primary drying period. First, overall vial heat transfer coefficient values, Kv, were determined by a gravimetric method based on pure ice sublimation experiments. Thus, it was possible to set up a map of the total heat flux received by each vial throughout the plate surface of our pilot scale freeze-dryer. Important heterogeneities were observed for the vials placed at the plate edges and for the vials placed at the center of the plate. As well, the same gravimetric method was also used to precisely determine the influence of main lyophilization operating parameters (shelf temperature and gas total pressure) or the vial types and sizes on these overall heat transfer coefficient values. A semi-empirical relationship as a function of total gas pressure was proposed. The transient method by pressure rise analysis (PRA method) after interrupting the water vapour flow between the sublimation chamber and the condenser, previously set up and validated in our laboratory, was then extensively used with an amorphous BSA-based formulation to identify the dried layer mass transfer resistance values, Rp, the ice front temperature, and the total heat transfer coefficient values, Kv, with or without annealing treatment. It was proved that this method gave accurate and coherent data only during the first half of the sublimation period when the totality of the vials of the set was still sublimating. Thus, this rapid method allowed estimation of, on line and in situ, the sublimation front temperature and the characterization of the morphology and structure of the freeze-dried layer, all along the first part of the sublimation period. The estimated sublimation temperatures shown by the PRA model were about 2 degrees C lower than the experimental values obtained using thermocouples inserted inside the vial, in accordance with previous data given by this method for similar freeze-drying conditions. As well, by using this method we could confirm the homogenization of the dried layer porous structure by annealing treatment after the freezing step. Furthermore, frozen matrix structure analysis (mean pore diameter) using optical microscopy and mass transfer modelling of water vapour by molecular diffusion (Knudsen regime) allowed, in some cases, to predict the experimental values of this overall mass transfer resistance directly related to the freeze-dried cake permeability. PMID:15971546

Hottot, A; Vessot, S; Andrieu, J

2005-01-01

403

Vertical Profiles of Latent Heat Release over the Global Tropics Using TRMM Rainfall Products from December 1997 to November 2002  

NASA Technical Reports Server (NTRS)

NASA Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) derived rainfall information will be used to estimate the four-dimensional structure of global monthly latent heating and rainfall profiles over the global tropics from December 1997 to November 2000. Rainfall, latent heating and radar reflectivity structures between El Nino (DJF 1997-98) and La Nina (DJF 1998-99) will be examined and compared. The seasonal variation of heating over various geographic locations (i.e., oceanic vs continental, Indian ocean vs west Pacific, Africa vs S. America) will also be analyzed. In addition, the relationship between rainfall, latent heating (maximum heating level), radar reflectivity and SST is examined and will be presented in the meeting. The impact of random error and bias in straitform percentage estimates from PR on latent heating profiles is studied and will also be presented in the meeting. The Goddard Cumulus Ensemble Model is being used to simulate various mesoscale convective systems that developed in different geographic locations. Specifically, the model estimated rainfall, radar reflectivity and latent heating profiles will be compared to observational data collected from TRMM field campaigns over the South China Sea in 1998 (SCSMXX), Brazil in 1999 (TRMM- LBA), and the central Pacific in 1999 (KWAJEX). Sounding diagnosed heating budgets and radar reflectivity from these experiments can provide the means to validate (heating product) as well as improve the GCE model.

Tao, W.-K.

2003-01-01

404

Vertical Profiles of Latent Heat Release over the Global Tropics using TRMM rainfall products from December 1997 to November 2001  

NASA Technical Reports Server (NTRS)

NASA Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) derived rainfall information will be used to estimate the four-dimensional structure of global monthly latent heating and rainfall profiles over the global tropics from December 1997 to November 2001. Rainfall, latent heating and radar reflectivity structures between El Nino (DE 1997-98) and La Nina (DJF 1998-99) will be examined and compared. The seasonal variation of heating over various geographic locations (i.e., oceanic vs continental, Indian ocean vs. west Pacific, Africa vs. S. America) will also be analyzed. In addition, the relationship between rainfall, latent heating (maximum heating level), radar reflectivity and SST is examined and will be presented in the meeting. The impact of random error and bias in strtaiform percentage estimates from PR on latent heating profiles is studied and will also be presented in the meeting. The Goddard Cumulus Ensemble Model is being used to simulate various mesoscale convective systems that developed in different geographic locations. Specifically, the model estimated rainfall, radar reflectivity and latent heating profiles will be compared to observational data collected from TRMM field campaigns over the South China Sea in 1998 (SCSMEX), Brazil in 1999 (TRMM-LBA), and the central Pacific in 1999 (KWAJEX). Sounding diagnosed heating budgets and radar reflectivity from these experiments can provide the means to validate (heating product) as well as improve the GCE model.

Tao, W.-K.; Lang, S.; Simpson, J.; Meneghini, R.; Halverson, J.; Johnson, R.; Adler, R.

2002-01-01

405

Vertical Profiles of Latent Heat Release Over the Global Tropics using TRMM Rainfall Products from December 1997 to November 2001  

NASA Technical Reports Server (NTRS)

NASA Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) derived rainfall information will be used to estimate the four-dimensional structure of global monthly latent heating and rainfall profiles over the global tropics from December 1997 to November 2000. Rainfall, latent heating and radar reflectivity structures between El Nino (DJF 1997-98) and La Nina (DJF 1998-99) will be examined and compared. The seasonal variation of heating over various geographic locations (i.e., oceanic vs continental, Indian ocean vs west Pacific, Africa vs S. America) will also be analyzed. In addition, the relationship between rainfall, latent heating (maximum heating level), radar reflectivity and SST is examined and will be presented in the meeting. The impact of random error and bias in stratiform percentage estimates from PR on latent heating profiles is studied and will also be presented in the meeting. The Goddard Cumulus Ensemble Model is being used to simulate various mesoscale convective systems that developed in different geographic locations. Specifically, the model estimated rainfall, radar reflectivity and latent heating profiles will be compared to observational data collected from TRMM field campaigns over the South China Sea in 1998 (SCSMEX), Brazil in 1999 (TRMM-LBA), and the central Pacific in 1999 (KWAJEX). Sounding diagnosed heating budgets and radar reflectivity from these experiments can provide the means to validate (heating product) as well as improve the GCE model.

Tao, W.-K.; Lang, S.; Simpson, J.; Meneghini, R.; Halverson, J.; Johnson, R.; Adler, R.; Starr, David (Technical Monitor)

2002-01-01

406

Different Assay Conditions for Detecting the Production and Release of Heat-Labile and Heat-Stable Toxins in Enterotoxigenic Escherichia coli Isolates  

PubMed Central

Enterotoxigenic Escherichia coli (ETEC) produce heat-labile (LT) and/or heat-stable enterotoxins (ST). Despite that, the mechanism of action of both toxins are well known, there is great controversy in the literature concerning the in vitro production and release of LT and, for ST, no major concerns have been discussed. Furthermore, the majority of published papers describe the use of only one or a few ETEC isolates to define the production and release of these toxins, which hinders the detection of ETEC by phenotypic approaches. Thus, the present study was undertaken to obtain a better understanding of ST and LT toxin production and release under laboratory conditions. Accordingly, a collection of 90 LT-, ST-, and ST/LT-producing ETEC isolates was used to determine a protocol for toxin production and release aimed at ETEC detection. For this, we used previously raised anti-LT antibodies and the anti-ST monoclonal and polyclonal antibodies described herein. The presence of bile salts and the use of certain antibiotics improved ETEC toxin production/release. Triton X-100, as chemical treatment, proved to be an alternative method for toxin release. Consequently, a common protocol that can increase the production and release of LT and ST toxins could facilitate and enhance the sensitivity of diagnostic tests for ETEC using the raised and described antibodies in the present work. PMID:24316604

Rocha, Letícia B.; Ozaki, Christiane Y.; Horton, Denise S. P. Q.; Menezes, Caroline A.; Silva, Anderson; Fernandes, Irene; Magnoli, Fabio C.; Vaz, Tania M. I.; Guth, Beatriz E. C.; Piazza, Roxane M. F.

2013-01-01

407

Different assay conditions for detecting the production and release of heat-labile and heat-stable toxins in enterotoxigenic Escherichia coli isolates.  

PubMed

Enterotoxigenic Escherichia coli (ETEC) produce heat-labile (LT) and/or heat-stable enterotoxins (ST). Despite that, the mechanism of action of both toxins are well known, there is great controversy in the literature concerning the in vitro production and release of LT and, for ST, no major concerns have been discussed. Furthermore, the majority of published papers describe the use of only one or a few ETEC isolates to define the production and release of these toxins, which hinders the detection of ETEC by phenotypic approaches. Thus, the present study was undertaken to obtain a better understanding of ST and LT toxin production and release under laboratory conditions. Accordingly, a collection of 90 LT-, ST-, and ST/LT-producing ETEC isolates was used to determine a protocol for toxin production and release aimed at ETEC detection. For this, we used previously raised anti-LT antibodies and the anti-ST monoclonal and polyclonal antibodies described herein. The presence of bile salts and the use of certain antibiotics improved ETEC toxin production/release. Triton X-100, as chemical treatment, proved to be an alternative method for toxin release. Consequently, a common protocol that can increase the production and release of LT and ST toxins could facilitate and enhance the sensitivity of diagnostic tests for ETEC using the raised and described antibodies in the present work. PMID:24316604

Rocha, Letícia B; Ozaki, Christiane Y; Horton, Denise S P Q; Menezes, Caroline A; Silva, Anderson; Fernandes, Irene; Magnoli, Fabio C; Vaz, Tania M I; Guth, Beatriz E C; Piazza, Roxane M F

2013-12-01

408

Assessing complexity of skin blood flow oscillations in response to locally applied heating and pressure in rats: Implications for pressure ulcer risk  

NASA Astrophysics Data System (ADS)

The objective of this study was to investigate the effects of local heating on the complexity of skin blood flow oscillations (BFO) under prolonged surface pressure in rats. Eleven Sprague-Dawley rats were studied: 7 rats underwent surface pressure with local heating (?t=10 °C) and 4 rats underwent pressure without heating. A pressure of 700 mmHg was applied to the right trochanter area of rats for 3 h. Skin blood flow was measured using laser Doppler flowmetry. The loading period was divided into nonoverlapping 30 min epochs. For each epoch, multifractal detrended fluctuation analysis (MDFA) was utilized to compute DFA coefficients and complexity of endothelial related metabolic, neurogenic, and myogenic frequencies of BFO. The results showed that under surface pressure, local heating led to a significant decrease in DFA coefficients of myogenic frequency during the initial epoch of loading period, a sustained decrease in complexity of myogenic frequency, and a significantly higher degree of complexity of metabolic frequency during the later phase of loading period. Surrogate tests showed that the reduction in complexity of myogenic frequency was associated with a loss of nonlinearity whereas increased complexity of metabolic frequency was associated with enhanced nonlinearity. Our results indicate that increased metabolic activity and decreased myogenic response due to local heating manifest themselves not only in magnitudes of metabolic and myogenic frequencies but also in their structural complexity. This study demonstrates the feasibility of using complexity analysis of BFO to monitor the ischemic status of weight-bearing skin and risk of pressure ulcers.

Liao, Fuyuan; O'Brien, William D.; Jan, Yih-Kuen

2013-10-01

409

Effect of nozzle configuration on transport in the stagnation zone of axisymmetric, impinging free-surface liquid jets: Part 2-local heat transfer  

SciTech Connect

This is the second of a two-part study on the flow structure and heat transfer characteristics of turbulent, free-surface liquid jets. Part 2 deals with the effect of selected nozzle configurations on the local heat transfer in the stagnation zone. Infrared techniques have been used to characterize the local heat transfer for the four nozzle configurations whose mean and turbulent flow structure was detailed in Part 1. The results show that for identical jet Reynolds numbers, significant differences exist in the magnitudes of the local Nusselt number for the nozzle types studied. Differences of approximately 40 percent were observed. Local heat transfer results reveal that for already turbulent jets, the mean radial velocity gradient appears to be more influential in determining the heat transfer than incremental changes in the level of turbulence (as measured by the radial component of the fluctuations). An empirical correlation of the experimental data supports this conclusion, and reveals that the stagnation Nusselt number is affected independently by the jet Reynolds number and the dimensionless mean radial velocity gradient. 21 refs., 6 figs.

Pan, Y.; Stevens, J.; Webb, B.W. (Brigham Young Univ., Provo, UT (United States))

1992-11-01

410

Dependence of flight behavior and heat production on air temperature in the green darner dragonfly Anax junius (Odonata: Aeshnidae)  

PubMed

The large, endothermic dragonfly Anax junius regulates the temperatures of its thorax (Tth) and head (Th) during flight. At high ambient temperature (Ta) it is able to dispose of excess heat from the thorax by increasing hemolymph circulation to the abdomen, but recent evidence suggests that heat loss to the abdomen is largely passive at Ta<30 °C. Nevertheless, these insects continue to regulate Tth and Th at least down to 20 °C and probably at much lower values of Ta. As Ta declines, A. junius glide less, probably fly faster when feeding, and increase their wingbeat frequency when patrolling. Presumably as a result of these behavioral changes, heat production, and thus inferred flight metabolic rate, is inversely proportional to Ta. This is the first demonstration based on field data that an insect regulates body temperature while flying by altering heat production. PMID:9320306

May

1995-01-01

411

A joint model of household space heat production and consumption: Empirical evidence from a Belgian micro-data survey  

SciTech Connect

Households are faced with increasing regulation to improve energy conservation and energy efficiency for environmental concerns. Understanding how a house produces space heat and how energy consumption can be reduced becomes a keystone in designing energy and environmental policies. This paper provides empirical evidence on household behavior in the context of house heating. A joint household space heat production and consumption model is developed and empirically implemented. Attention is devoted mainly to the intermediate role of the characteristics of the house, with special reference to insulation levels, which determine the ability of the house to convert energy into heat levels. House heat levels are characterized and empirical support for the so-called {open_quote}rebound{close_quote} effects are shown. The econometric model is specified for a single period cross-section regression estimation, The database is drawn from the 1987-88 Belgian Household Expenditure Survey.

Cuijpers, C.

1995-12-31

412

Differential effects of foods traditionally regarded as ‘heating’ and ‘cooling’ on prostaglandin E 2 production by a macrophage cell line  

Microsoft Academic Search

Some components of natural foods may enhance or inhibit prostaglandin formation and potentially affect the inflammation condition. A macrophage cell line, RAW264.7, was employed to examine the effects of foods traditionally regarded as ‘heating’ or ‘cooling’ on the production of PGE2, a well-known proinflammatory mediator. Foods traditionally regarded as ‘heating’ (litchi, longan, and dried longan) or ‘cooling’ (chrysanthemum flower, bitter

Ching-jang Huang; Mei-Chiao Wu

2002-01-01

413

Oxidation of chlorinated ethenes by heat-activated persulfate: kinetics and products.  

PubMed

In situ chemical oxidation (ISCO) and in situ thermal remediation (ISTR) are applicable to treatment of groundwater contaminated with chlorinated ethenes. ISCO with persulfate (S2O8(2-)) requires activation, and this can be achieved with the heat from ISTR, so there may be advantages to combining these technologies. To explore this possibility, we determined the kinetics and products of chlorinated ethene oxidation with heat-activated persulfate and compared them to the temperature dependence of other degradation pathways. The kinetics of chlorinated ethene disappearance were pseudo-first-order for 1-2 half-lives, and the resulting rate constants-measured from 30 to 70 degrees C--fit the Arrhenius equation, yielding apparent activation energies of 101 +/- 4 kJ mol(-1) for tetrachloroethene (PCE), 108 +/- 3 kJ mol(-1) for trichloroethene (TCE), 144 +/- 5 kJ mol(-1) for cis-1,2-dichloroethene (cis-DCE), and 141 +/- 2 kJ mol(-1) for trans-1,2-dichloroethene (trans-DCE). Chlorinated byproducts were observed, but most of the parent material was completely dechlorinated. Arrhenius parameters for hydrolysis and oxidation by persulfate or permanganate were used to calculate rates of chlorinated ethene degradation by these processes over the range of temperatures relevant to ISTR and the range of oxidant concentrations and pH relevant to ISCO. PMID:17328217

Waldemer, Rachel H; Tratnyek, Paul G; Johnson, Richard L; Nurmi, James T

2007-02-01

414

Production of 238PuO2 heat sources for the Cassini mission  

NASA Astrophysics Data System (ADS)

NASA's Cassini mission to Saturn, scheduled to launch in October, 1997, is perhaps the most ambitious interplanetary explorer ever constructed. Electric power for the spacecraft's science instruments and on-board computers will be provided by three radioisotope thermoelectric generators (RTGs) powered by 216 238PuO2-fueled General-Purpose Heat Source (GPHS) capsules. In addition, critical equipment and instruments on the spacecraft and Huygens probe will be warmed by 128 Light-Weight Radioisotope Heater Units (LWRHUs). Fabrication and assembly of the GPHS capsules and LWRHU heat sources was performed at Los Alamos National Laboratory (LANL) between January 1994 and September 1996. During this production campaign, LANL pressed and sintered 315 GPHS fuel pellets and 181 LWRHU pellets. By October 1996, NMT-9 had delivered a total of 235 GPHS capsules to EG&G Mound Applied Technologies (EG&G MAT) in Miamisburg, Ohio. EG&G MAT conditioned the capsules for use, loaded the capsules into the Cassini RTGs, tested the RTGs, and coordinated transportation to Kennedy Space Center (KSC). LANL also fabricated and assembled a total of 180 LWRHUs. The LWRHUs required for the Cassini spacecraft were shipped to KSC in mid-1997.

George, Timothy G.; Foltyn, Elizabeth M.

1998-01-01

415

Heat and Mass Transfer Measurements for Tray-Fermented Fungal Products  

NASA Astrophysics Data System (ADS)

In this study, heat and mass transfer in static tray fermentation, which is widely used in solid-state fermentation (SSF) to produce fungal products, such as enzymes or koji, is investigated. Specifically, kinetic models of transport phenomena in the whole-tray chamber are emphasized. The effects of temperature, moisture, and humidity on microbial growth in large-scale static tray fermentation are essential to scale-up SSF and achieve uniform fermentation. In addition, heat and mass transfer of static tray fermentation of Trichoderma fungi with two tray setups—traditional linen coverings and stacks in a temperature-humidity chamber is examined. In both these setups, the following factors of fermentation were measured: air velocity, air temperature, illumination, pH, carbon dioxide (CO2) concentration, and substrate temperature, and the effects of bed height, moisture of substrate, and relative humidity of air are studied. A thin (1 cm) bed at 28 °C and 95 % relative humidity is found to be optimum. Furthermore, mixing was essential for achieving uniform fermentation of Trichoderma fungi. This study has important applications in large-scale static tray fermentation of fungi.

Jou, R.-Y.; Lo, C.-T.

2011-01-01

416

Optimization of the Mu2e Production Solenoid Heat and Radiation Shield  

NASA Astrophysics Data System (ADS)

The Mu2e experiment at Fermilab is designed to study the conversion of a negative muon to electron in the field of a nucleus without emission of neutrinos. Observation of this process would provide unambiguous evidence for physics beyond the Standard Model, and can point to new physics beyond the reach of the LHC. The main parts of the Mu2e apparatus are its superconducting solenoids: Production Solenoid (PS), Transport Solenoid (TS), and Detector Solenoid (DS). Being in the vicinity of the beam, PS magnets are most subjected to the radiation damage. In order for the PS superconducting magnet to operate reliably, the peak neutron flux in the PS coils must be reduced by 3 orders of magnitude by means of sophisticatedly designed massive Heat and Radiation Shield (HRS), optimized for the performance and cost. An issue with radiation damage is related to large residual electrical resistivity degradation in the superconducting coils, especially its Al stabilizer. A detailed MARS15 analysis and optimization of the HRS has been carried out both to satisfy the Mu2e requirements to the radiation quantities (such as displacements per atom, peak temperature and power density in the coils, absorbed dose in the insulation, and dynamic heat load) and cost. Results of MARS15 simulations of these radiation quantities are reported and optimized HRS models are presented; it is shown that design levels satisfy all requirements.

Pronskikh, V. S.; Coleman, R.; Glenzinski, D.; Kashikhin, V. V.; Mokhov, N. V.

2014-03-01

417

Changes in Quartz During Heating and the Possible Effects on Si Production  

NASA Astrophysics Data System (ADS)

In Si and FeSi production, the main Si source is SiO2, in the form of quartz. Reactions with SiO2 generate SiO gas that further reacts with SiC to Si. During heating, quartz will transform to other SiO2 modifications with cristobalite as the stable high-temperature phase. Transformation to cristobalite is a slow process. Its rate has been investigated for several industrial quartz sources and has been shown to vary considerably among the different quartz types. Other differences in behavior during heating between these quartz sources, such as softening temperature and volume expansion, have also been studied. The quartz-cristobalite ratio will affect the rate of reactions involving SiO2. The industrial consequences and other implications of the observed difference between quartz types are discussed. Initial studies of industrial quartz were published by Ringdalen et al. In the current work, a new experimental method has been developed, and an investigation of several new quartz sources has confirmed the earlier observed large variation between different sources. The repeatability of the data has been studied and the effect of gas atmosphere investigated. The results from the earlier work are included as a basis for the discussion.

Ringdalen, Eli

2015-02-01

418

Characterization of a flow-through microcalorimeter for measuring the heat production of cardiac trabeculae  

NASA Astrophysics Data System (ADS)

The energy consumption of isolated cardiac trabeculae can be inferred from measurements of their heat production. Once excised from the heart, to remain viable, trabeculae require continuous superfusion with an oxygen- and nutrient-rich solution. Flow-through calorimeters enable trabeculae to be maintained in a stable and controlled environment for many hours at a time. In this paper we describe and characterize a flow-through microcalorimeter, with sensitivity in the 1?W range, for measuring the heat output of 10?g cardiac trabeculae. The device uses infrared-sensitive, thin-film thermopile sensors to provide a noncontact method for measuring temperature differences. The sensors are capable of resolving 5?K temperature differences within the superfusing fluid. The microcalorimeter has a sensitivity of 2.56V/W at a flow rate of 1?l/s, with a time constant of approximately 3.5 s. The sensitivity and time constant are strongly dependent upon the flow rate. Predictions of a finite-element model of the calorimeter's characteristics compare favorably with measured data over a wide range of flow rates.

Taberner, A. J.; Hunter, I. W.; Kirton, R. S.; Nielsen, P. M. F.; Loiselle, D. S.

2005-10-01

419

Aspen Plus® and economic modeling of equine waste utilization for localized hot water heating via fast pyrolysis.  

PubMed

Aspen Plus(®) based simulation models have been developed to design a pyrolysis process for on-site production and utilization of pyrolysis oil from equine waste at the Equine Rehabilitation Center at Morrisville State College (MSC). The results indicate that utilization of all the available waste from the site's 41 horses requires a 6 oven dry metric ton per day (ODMTPD) pyrolysis system but it will require a 15 ODMTPD system for waste generated by an additional 150 horses at the expanded area including the College and its vicinity. For this a dual fluidized bed combustion reduction integrated pyrolysis system (CRIPS) developed at USDA's Agricultural Research Service (ARS) was identified as the technology of choice for pyrolysis oil production. The Aspen Plus(®) model was further used to consider the combustion of the produced pyrolysis oil (bio-oil) in the existing boilers that generate hot water for space heating at the Equine Center. The model results show the potential for both the equine facility and the College to displace diesel fuel (fossil) with renewable pyrolysis oil and alleviate a costly waste disposal problem. We predict that all the heat required to operate the pyrolyzer could be supplied by non-condensable gas and about 40% of the biochar co-produced with bio-oil. Techno-economic Analysis shows neither design is economical at current market conditions; however the 15 ODMTPD CRIPS design would break even when diesel prices reach $11.40/gal. This can be further improved to $7.50/gal if the design capacity is maintained at 6 ODMTPD but operated at 4950 h per annum. PMID:23845952

Hammer, Nicole L; Boateng, Akwasi A; Mullen, Charles A; Wheeler, M Clayton

2013-10-15

420

Heat shock induces production of reactive oxygen species and increases inner mitochondrial membrane potential in winter wheat cells.  

PubMed

Heat shock leads to oxidative stress. Excessive ROS (reactive oxygen species) accumulation could be responsible for expression of genes of heat-shock proteins or for cell death. It is known that in isolated mammalian mitochondria high protonic potential on the inner membrane actuates the production of ROS. Changes in viability, ROS content, and mitochondrial membrane potential value have been studied in winter wheat (Triticum aestivum L.) cultured cells under heat treatment. Elevation of temperature to 37-50°C was found to induce elevated ROS generation and increased mitochondrial membrane potential, but it did not affect viability immediately after treatment. More severe heat exposure (55-60°C) was not accompanied by mitochondrial potential elevation and increased ROS production, but it led to instant cell death. A positive correlation between mitochondrial potential and ROS production was observed. Depolarization of the mitochondrial membrane by the protonophore CCCP inhibited ROS generation under the heating conditions. These data suggest that temperature elevation leads to mitochondrial membrane hyperpolarization in winter wheat cultured cells, which in turn causes the increased ROS production. PMID:25540005

Fedyaeva, A V; Stepanov, A V; Lyubushkina, I V; Pobezhimova, T P; Rikhvanov, E G

2014-11-01

421

Retrieved Vertical Profiles of Latent Heat Release Using TRMM Rainfall Products  

NASA Technical Reports Server (NTRS)

This paper represents the first attempt to use TRMM rainfall information to estimate the four dimensional latent heating structure over the global tropics for February 1998. The mean latent heating profiles over six oceanic regions (TOGA COARE IFA, Central Pacific, S. Pacific Convergence Zone, East Pacific, Indian Ocean and Atlantic Ocean) and three continental regions (S. America, Central Africa and Australia) are estimated and studied. The heating profiles obtained from the results of diagnostic budget studies over a broad range of geographic locations are used to provide comparisons and indirect validation for the heating algorithm estimated heating profiles. Three different latent heating algorithms, the Goddard Convective-Stratiform (CSH) heating, the Goddard Profiling (GPROF) heating, and the Hydrometeor heating (HH) are used and their results are intercompared. The horizontal distribution or patterns of latent heat release from the three different heating retrieval methods are quite similar. They all can identify the areas of major convective activity (i.e., a well defined ITCZ in the Pacific, a distinct SPCZ) in the global tropics. The magnitude of their estimated latent heating release is also not in bad agreement with each other and with those determined from diagnostic budget studies. However, the major difference among these three heating retrieval algorithms is the altitude of the maximum heating level. The CSH algorithm estimated heating profiles only show one maximum heating level, and the level varies between convective activity from various geographic locations. These features are in good agreement with diagnostic budget studies. By contrast, two maximum heating levels were found using the GPROF heating and HH algorithms. The latent heating profiles estimated from all three methods can not show cooling between active convective events. We also examined the impact of different TMI (Multi-channel Passive Microwave Sensor) and PR (Precipitation Radar) rainfall information on latent heating structures.

Tao, W.-K.; Lang, S.; Olson, W. S.; Meneghini, R.; Yang, S.; Simpson, J.; Kummerow, C.; Smith, E.

2000-01-01

422

Enhancing methane production from waste activated sludge using combined free nitrous acid and heat pre-treatment.  

PubMed

Methane production from anaerobic digestion of waste activated sludge (WAS) is often limited by the slow degradation and poor substrate availability of WAS. Our previous study revealed that WAS pre-treatment using free nitrous acid (FNA, i.e. HNO2) is an economically feasible and environmentally friendly method for promoting methane production. In order to further improve methane production from WAS, this study presents a novel strategy based on combined FNA and heat pre-treatment. WAS from a full-scale plant was treated for 24 h with FNA alone (0.52-1.43 mg N/L at 25 °C), heat alone (35, 55 and 70 °C), and FNA (0.52-1.11 mg N/L) combined with heat (35, 55 and 70 °C). The pre-treated WAS was then used for biochemical methane potential tests. Compared to the control (no FNA or heat pre-treatment of WAS), biochemical methane potential of the pre-treated WAS was increased by 12-16%, 0-6%, 17-26%, respectively; hydrolysis rate was improved by 15-25%, 10-25%, 20-25%, respectively, for the three types of pre-treatment. Heat pre-treatment at 55 and 70 °C, independent of the presence or absence of FNA, achieved approximately 4.5 log inactivation of pathogens (in comparison to ?1 log inactivation with FNA treatment alone), thus capable of producing Class A biosolids. The combined FNA and heat pre-treatment is an economically and environmentally attractive technology for the pre-treatment of WAS prior to anaerobic digestion, particularly considering that both FNA and heat can be produced as by-products of anaerobic sludge digestion. PMID:24981745

Wang, Qilin; Jiang, Guangming; Ye, Liu; Yuan, Zhiguo

2014-10-15

423

Detection of horse meat contamination in raw and heat-processed meat products.  

PubMed

Europe's recent problems with the adulteration of beef products with horse meat highlight the need for a reliable method for detecting horse meat in food for human consumption. The objective of this study was therefore to develop a reliable monoclonal antibody (mAb) based enzyme-linked immunosorbent assay (ELISA) for horse meat detection. Two mAbs, H3E3 (IgG2b) and H4E7 (IgG2a), were characterized as horse-selective, and competitive ELISAs (cELISAs) employing these mAbs were developed. The cELISAs were found to be capable of detecting levels as low as 1% of horse meat in raw, cooked, and autoclaved ground beef or pork, being useful analytical tools for addressing the health, economic, and ethical concerns associated with adulterating meat products with horse meat. However, due to cross-reaction with raw poultry meat, it is recommended that samples be heated (100 °C for 15 min) prior to analysis to eliminate possible false-positive results. PMID:25474205

Hsieh, Yun-Hwa P; Ofori, Jack A

2014-12-31

424

Low-cost multi-vehicle air temperature measurements for heat load assessment in local-scale climate applications  

NASA Astrophysics Data System (ADS)

In the recent years there has been a strong interest in exploring the potential of low-cost measurement devices as alternative source of meteorological monitoring data, especially in the urban areas where high-density observations become crucial for appropriate heat load assessment. One of the simple, but efficient approaches for gathering large amount of spatial data is through mobile measurement campaigns in which the sensors are attached to driving vehicles. However, non-standardized data collecting procedure, instrument quality, their response-time and design, variable device ventilation and radiation protection influence the reliability of the gathered data. We investigate what accuracy can be expected from the data collected through low-cost mobile measurements and whether the achieved quality of the data is sufficient for validation of the state-of-the-art local-scale climate models. We tested 5 types of temperature sensors and data loggers: Maxim iButton, Lascar EL-USB-2-LCD+ and Onset HOBO UX100-003 as market available devices and self-designed solar powered Arduino-based data loggers combined with the AOSONG AM2315 and Sensirion SHT21 temperature and humidity sensors. The devices were calibrated and tested in stationary mode at the Austrian Weather Service showing accuracy between 0.1°C and 0.8°C, which was mostly within the device specification range. In mobile mode, the best response-time was found for self-designed device with Arduino-based data logger and Sensirion SHT21 sensor. However, the device lacks the mechanical robustness and should be further improved for broad-range applications. We organized 4 measurement tours: two taking place in urban environment (Vienna, Austria in July 2011 and July 2013) and two in countryside with complex terrain of Mid-Adriatic islands (Hvar and Korcula, Croatia in August 2013). Measurements were taken on clear-sky, dry and hot days. We combined multiple devices attached to bicycle and cars with different radiation protection. Duration of each measurement tour lasted approximately 2 hours covering the distances in radius of about 10-30 km, logging the air temperature and geographical positioning in intervals of 1-5 seconds. The collected data were aggregated on a 100 m horizontal resolution grid and compared with the local-scale climate modelling simulations with the urban climate model MUKLIMO3 initialized with the atmospheric conditions for a given day. Both measurement and modelling results show similar features for distinct local climate zones (built-up area, near water environment, forest, parks, agricultural area, etc). The spatial gradients in temperature can be assigned to different orographical and land use characteristics. Even if many ambiguities remain in both modelling and the measurement approach, the collected data provide useful information for local-scale heat assessment and can serve as a base to increase the model reliability, especially in areas with low data coverage.

Zuvela-Aloise, Maja; Weyss, Gernot; Aloise, Giulliano; Mifka, Boris; Löffelmann, Philemon; Hollosi, Brigitta; Nemec, Johana; Vucetic, Visnja

2014-05-01

425

Biogeographic affinity helps explain productivity-richness relationships at regional and local scales  

USGS Publications Warehouse

The unresolved question of what causes the observed positive relationship between large-scale productivity and species richness has long interested ecologists and evolutionists. Here we examine a potential explanation that we call the biogeographic affinity hypothesis, which proposes that the productivity-richness relationship is a function of species' climatic tolerances that in turn are shaped by the earth's climatic history combined with evolutionary niche conservatism. Using botanical data from regions and sites across California, we find support for a key prediction of this hypothesis, namely, that the productivity-species richness relationship differs strongly and predictably among groups of higher taxa on the basis of their biogeographic affinities (i.e., between families or genera primarily associated with north-temperate, semiarid, or desert zones). We also show that a consideration of biogeographic affinity can yield new insights on how productivity-richness patterns at large geographic scales filter down to affect patterns of species richness and composition within local communities. ?? 2007 by The University of Chicago. All rights reserved.

Harrison, S.; Grace, J.B.

2007-01-01

426

Three-Dimensional transient heat conduction in a functionally graded thick plate with a higher-order plate theory and a meshless local Petrov-Galerkin method  

Microsoft Academic Search

We analyze transient heat conduction in a thick functionally graded plate by using a higher-order plate theory and a meshless local Petrov-Galerkin (MLPG) method. The temperature field is expanded in the thickness direction by using Legendre polynomials as basis functions. For temperature prescribed on one or both major surfaces of the plate, modified Lagrange polynomials are used as basis and

L. F. Qian; R. C. Batra

2005-01-01

427

Influence of the local heating position on the terahertz emission power from high-Tc superconducting Bi2Sr2CaCu2O8+? mesas  

NASA Astrophysics Data System (ADS)

Simultaneous measurements of spectroscopic terahertz emissions from and SiC photoluminescent local temperature T(r) distributions of high transition temperature Tc superconducting Bi2Sr2CaCu2O8+? rectangular mesa devices were made. A local region with T(r) > Tc known as a hot spot can emerge with current bias changes. When the hot spot position was moved to a mesa end by locally heating the mesa surface with a laser beam, the intensity of the emission increased, but no changes to its frequency or line width were observed. These results suggest that higher power radiation is attainable by adjusting the hot spot position.

Watanabe, C.; Minami, H.; Kitamura, T.; Asanuma, K.; Nakade, K.; Yasui, T.; Saiwai, Y.; Shibano, Y.; Yamamoto, T.; Kashiwagi, T.; Klemm, Richard A.; Kadowaki, K.

2015-01-01

428

Dynamics and localization of H2O2 production in elicited plant cells.  

PubMed

H(2)O(2) produced in plant cells plays a dual role. In addition to its antimicrobial effect, it also acts as a secondary messenger initiating and modulating responses of plants exposed to unfavorable external signals. A suspension culture of Rubia tinctorum cells challenged with elicitors was used as a model system to investigate H(2)O(2) formation. Cellular H(2)O(2) was measured by a modified titanium(IV) method, while that in the medium was detected with scopoletin fluorescence. Localization of H(2)O(2) production at the ultrastructural level was carried out by the CeCl(3) reaction. A fungal elicitor induced H(2)O(2) production with transient maxima, the first of which appeared 4 min after treatment. Three subsequent maxima appeared in the cells up to 48 h after treatment. Exposure of cells to exogenous jasmonic acid and salicylic acid also changed the H(2)O(2) concentration maxima over 48 h; however, their timing was slightly shifted. Fungal-elicitor, jasmonic acid, and salicylic acid treatments had different effects on the H(2)O(2) concentration in the medium. Ultrastructural investigations revealed that electron-dense precipitates were present at the plasmalemma and in some nearby vesicular cytoplasmic structures 30 min after treatment. Later samples showed cytochemical-precipitate accumulation in the cell walls. These deposits appeared to be local and independent of the direction of the external signal. We could not detect the presence of H(2)O(2) in peroxisomes, mitochondria, plastids, or the central vacuolar space. Electron energy loss spectroscopy investigations distinguished between the cerium-containing precipitates and other electrondense particles, thereby proving that H(2)O(2) generation occurs locally. PMID:17351735

Bóka, K; Orbán, N; Kristóf, Z

2007-01-01

429

Heat production in depth up to 2500m via in situ combustion of methane using a counter-current heat-exchange reactor  

NASA Astrophysics Data System (ADS)

In situ combustion is a well-known method used for exploitation of unconventional oil deposits such as heavy oil/bitumen reservoirs where the required heat is produced directly within the oil reservoir by combustion of a small percentage of the oil. A new application of in situ combustion for the production of methane from hydrate-bearing sediments was tested at pilot plant scale within the first phase of the German national gas hydrate project SUGAR. The applied method of in situ combustion was a flameless, catalytic oxidation of CH4 in a counter-current heat-exchange reactor with no direct contact between the catalytic reaction zone and the reservoir. The catalyst permitted a flameless combustion of CH4 with air to CO2 and H2O below the auto-ignition temperature of CH4 in air (868 K) and outside the flammability limits. This led to a double secured application of the reactor. The relatively low reaction temperature allowed the use of cost-effective standard materials for the reactor and prevented NOx formation. Preliminary results were promising and showed that only 15% of the produced CH4 was needed to be catalytically burned to provide enough heat to dissociate the hydrates in the environment and release CH4. The location of the heat source right within the hydrate-bearing sediment is a major advantage for the gas production from natural gas hydrates as the heat is generated where it is needed without loss of energy due to transportation. As part of the second period of the SUGAR project the reactor prototype of the first project phase was developed further to a borehole tool. The dimensions of this counter-current heat-exchange reactor are about 540 cm in length and 9 cm in diameter. It is designed for applications up to depths of 2500 m. A functionality test and a pressure test of the reactor were successfully carried out in October 2013 at the continental deep drilling site (KTB) in Windischeschenbach, Germany, in 600 m depth and 2000 m depth, respectively. In this study we present technical details of the reactor, the catalyst and potential fields of application beside the production of natural gas from hydrate bearing sediments.

Schicks, Judith Maria; Spangenberg, Erik; Giese, Ronny; Heeschen, Katja; Priegnitz, Mike; Luzi-Helbing, Manja; Thaler, Jan; Abendroth, Sven; Klump, Jens

2014-05-01

430

Local regression models for spatial interpolation of urban heat island—an example from Wroc?aw, SW Poland  

NASA Astrophysics Data System (ADS)

Geographically weighted regression algorithm (GWR) has been applied to derive the spatial structure of urban heat island (UHI) in the city of Wroc?aw, SW Poland. Seven UHI cases, measured during various meteorological conditions and characteristic of different seasons, were selected for analysis. GWR results were compared with global regression models (MLR), using various statistical procedures including corrected Akaike Information Criterion, determination coefficient, analysis of variance, and Moran's I index. It was found that GWR is better suited for spatial modeling of UHI than MLR models, as it takes into account non-stationarity of the spatial process. However, Monte Carlo and F3 tests for spatial stationarity of the independent variables suggest that for several spatial predictors a mixed GWR-MLR approach is recommended. Both local and global models were extended by the interpolation of regression residuals and used for spatial interpolation of the UHI structure. The interpolation results were evaluated with the cross-validation approach. It was found that the incorporation of the spatially interpolated residuals leads to significant improvement of the interpolation results for both GWR and MLR approaches. Because GWR is better justified in terms of statistical specification, the combined GWR + interpolated regression residuals (GWR residual kriging; GWRK) approach is recommended for spatial modeling of UHI, instead of widely applied MLR models.

Szymanowski, Mariusz; Kryza, Maciej

2012-04-01

431

Evidence of local power deposition and electron heating by a standing electromagnetic wave in electron-cyclotron-resonance plasma.  

PubMed

Microwave plasmas excited at electron-cyclotron resonance were studied in the 0.5-15 mTorr pressure range. In contrast with low-limit pressure conditions where the plasma emission highlights a fairly homogeneous spatial structure, a periodic spatial modulation (period ?6.2 cm) appeared as pressure increased. This feature is ascribed to a local power deposition (related to the electron density) due to the presence of a standing electromagnetic wave created by the feed electromagnetic field (2.45 GHz) in the cavity formed by the reactor walls. Analysis of the electron energy probability function by Langmuir probe and optical emission spectroscopy further revealed the presence of a high-energy tail that showed strong periodic spatial modulation at higher pressure. The spatial evolution of the electron density and of the characteristic temperature of these high-energy electrons coincides with the nodes (maximum) and antinodes (minimum) of the standing wave. These spatially-modulated power deposition and electron heating mechanisms are then discussed. PMID:25314546

Durocher-Jean, A; Stafford, L; Dap, S; Makasheva, K; Clergereaux, R

2014-09-01

432

Evidence of local power deposition and electron heating by a standing electromagnetic wave in electron-cyclotron-resonance plasma  

NASA Astrophysics Data System (ADS)

Microwave plasmas excited at electron-cyclotron resonance were studied in the 0.5-15 mTorr pressure range. In contrast with low-limit pressure conditions where the plasma emission highlights a fairly homogeneous spatial structure, a periodic spatial modulation (period ˜6.2 cm) appeared as pressure increased. This feature is ascribed to a local power deposition (related to the electron density) due to the presence of a standing electromagnetic wave created by the feed electromagnetic field (2.45 GHz) in the cavity formed by the reactor walls. Analysis of the electron energy probability function by Langmuir probe and optical emission spectroscopy further revealed the presence of a high-energy tail that showed strong periodic spatial modulation at higher pressure. The spatial evolution of the electron density and of the characteristic temperature of these high-energy electrons coincides with the nodes (maximum) and antinodes (minimum) of the standing wave. These spatially-modulated power deposition and electron heating mechanisms are then discussed.

Durocher-Jean, A.; Stafford, L.; Dap, S.; Makasheva, K.; Clergereaux, R.

2014-09-01

433

Fruit-localized phytochromes regulate lycopene accumulation independently of ethylene production in tomato.  

PubMed

We show that phytochromes modulate differentially various facets of light-induced ripening of tomato fruit (Solanum lycopersicum L.). Northern anal