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1

Nuclear localization and the heat shock proteins  

Microsoft Academic Search

The highly conserved heat shock proteins (HSP) belong to a subset of cellular proteins that localize to the nucleus. HSPs\\u000a are atypical nuclear proteins in that they localize to the nucleus selectively, rather than invariably. Nuclear localization\\u000a of HSPs is associated with cell stress and cell growth. This aspect of HSPs is highly conserved with nuclear localization\\u000a occurring in response

A. A. Knowlton; M. Salfity

1996-01-01

2

Free forming of locally heated specimens  

Microsoft Academic Search

A novel manufacturing method is investigated, in which a steep temperature gradient within the workpiece is induced to facilitate material flow locally. By this method, complex shapes can be formed without complicated dies. The feasibility of the idea is analyzed experimentally and numerically. Local heating is realized either by means of induction or laser heating. Experiments using materials 16MnCr5, X5CrNi18\\/9,

O. Okman; M. Özmen; H. Huwiler; A. E. Tekkaya

2007-01-01

3

Local heating realization by reverse thermal cloak  

PubMed Central

Transformation thermodynamics, as one of the important branches among the extensions of transformation optics, has attracted plentiful attentions and interests recently. The result of transformation thermodynamics, or called as “thermal cloak”, can realize isothermal region and hide objects from heat. In this paper, we presented the concept of “reverse thermal cloak” to correspond to the thermal cloak and made a simple engineering definition to identify them. By full-wave simulations, we verified that the reverse thermal cloak can concentrate heat and realize local heating. The performance of local heating depends on the anisotropic dispersion of the cloaking layer's thermal conductivity. Three-dimensional finite element simulations demonstrated that the reverse thermal cloak can be used to heat up objects. Besides pre-engineered metamaterials, such reverse thermal cloak can even be realized with homogenous materials by alternating spoke-like structure or Hashin coated-sphere structure. PMID:24398592

Hu, Run; Wei, Xuli; Hu, Jinyan; Luo, Xiaobing

2014-01-01

4

Local heating realization by reverse thermal cloak.  

PubMed

Transformation thermodynamics, as one of the important branches among the extensions of transformation optics, has attracted plentiful attentions and interests recently. The result of transformation thermodynamics, or called as "thermal cloak", can realize isothermal region and hide objects from heat. In this paper, we presented the concept of "reverse thermal cloak" to correspond to the thermal cloak and made a simple engineering definition to identify them. By full-wave simulations, we verified that the reverse thermal cloak can concentrate heat and realize local heating. The performance of local heating depends on the anisotropic dispersion of the cloaking layer's thermal conductivity. Three-dimensional finite element simulations demonstrated that the reverse thermal cloak can be used to heat up objects. Besides pre-engineered metamaterials, such reverse thermal cloak can even be realized with homogenous materials by alternating spoke-like structure or Hashin coated-sphere structure. PMID:24398592

Hu, Run; Wei, Xuli; Hu, Jinyan; Luo, Xiaobing

2014-01-01

5

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

6

Localization of small heat shock proteins to the higher plant endomembrane system. [Low-molecular-weight heat shock proteins  

SciTech Connect

Most eukaryotic cells respond to high temperature and other stresses with the production of heat shock proteins, which aid in cell survival. There are four major classes of heat shock proteins HSP90, HSP70, HSP60 and low-molecular weight HSP. The data from this research indicate that members of the low-molecular weight heat shock proteins are most likely resident endoplasmic reticulum (ER) proteins and may be similar in function to related low-molecular weight heat shock proteins in the cytoplasm. The low-molecular weight heat shock proteins, the HSP90 and the HSP70 all appear to localize to the endoplasmic reticulum. Since the ER-localized low-molecular weight heat shock proteins are physically separated from their counterparts in other cell compartments, investigations of the ER-localized heat shock proteins provides a simplified model system for determining the functions of low-molecular weight heat shock proteins in eukaryotes.

Helm, K.W.; Vierling, E. (Univ. of Arizona, Tucson (United States)); LaFayette, P.R.; Nagao, R.T.; Key, J.L. (Univ. of Georgia, Athens (United States))

1993-01-01

7

Thermal response of a flat heat pipe sandwich structure to a localized heat flux  

E-print Network

Thermal response of a flat heat pipe sandwich structure to a localized heat flux G. Carbajal a , C The temperature distribution across a flat heat pipe sandwich structure, subjected to an intense localized thermal to the evaporator side of the flat heat pipe, while the condenser side was cooled via natural convective

Wadley, Haydn

8

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

9

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

10

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

11

Productivity Improvement for State and Local Government.  

National Technical Information Service (NTIS)

A wide variety of works on productivity improvement approaches for State and local governments are cited in this annotated bibliography for the local government policymaker, chief executive officer, or department manager interested in improving personal o...

1981-01-01

12

Local effects of longitudinal heat conduction in plate heat exchangers  

Microsoft Academic Search

In a plate heat exchanger, heat transfer from the hot to the cold fluid is a multi-dimensional conjugate problem, in which longitudinal heat conduction (LHC) along the dividing walls often plays some role and can not be neglected. Large-scale, or end-to-end, LHC is always detrimental to the exchanger’s effectiveness. On the contrary, if significant non-uniformities exist in the distribution of

Michele Ciofalo

2007-01-01

13

Local lettuce: heat tolerant romaine cultivars and vermicompost soil amendment to increase sustainability in the Mid-Atlantic .  

E-print Network

??Local production of lettuce in the Mid-Atlantic utilizing heat-tolerant romaine cultivars and vermicompost soil amendment has the potential to significantly increase sustainability of agriculture. Heat… (more)

Wallis, Anna Elizabeth

2014-01-01

14

Mode localization of a component cooling water heat exchanger  

Microsoft Academic Search

In a nuclear power plant, the tubes of a component cooling water heat exchanger are frequently affected by cold and hot fluid shock waves. Thus, tubes are often found to be worn out. This wear may alter the dynamics of the tubes and introduce mode localization in the heat exchanger. This paper examines mode localization in a component cooling water

Bo-Wun Huang; Huang-Kuang Kung

2005-01-01

15

Local heating of heterogeneous current-carrying conductors Yu. Dolinskya)  

E-print Network

's surface. We analyze different components of Joule heating, which are associated with the change on structural material changes in conductors is Joule heating. A separate investigation of the effect of JouleLocal heating of heterogeneous current-carrying conductors Yu. Dolinskya) and T. Elperina

Elperin, Tov

16

Measurement of local high-level, transient surface heat flux  

NASA Technical Reports Server (NTRS)

This study is part of a continuing investigation to develop methods for measuring local transient surface heat flux. A method is presented for simultaneous measurements of dual heat fluxes at a surface location by considering the heat flux as a separate function of heat stored and heat conducted within a heat flux gage. Surface heat flux information is obtained from transient temperature measurements taken at points within the gage. Heat flux was determined over a range of 4 to 22 MW/sq m. It was concluded that the method is feasible. Possible applications are for heat flux measurements on the turbine blade surfaces of space shuttle main engine turbopumps and on the component surfaces of rocket and advanced gas turbine engines and for testing sensors in heat flux gage calibrators.

Liebert, Curt H.

1988-01-01

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

Limits of localized heating by electromagnetically excited nanoparticles  

NASA Astrophysics Data System (ADS)

Based on an analysis of the diffusive heat flow equation, we determine limits on the localization of heating of soft materials and biological tissues by electromagnetically excited nanoparticles. For heating by rf magnetic fields or heating by typical continuous wave lasers, the local temperature rise adjacent to magnetic or metallic nanoparticles is negligible. However, heat dissipation for a large number of nanoparticles dispersed in a macroscopic region of a material or tissue produces a global temperature rise that is orders of magnitude larger than the temperature rise adjacent to a single nanoparticle. One approach for producing a significant local temperature rise on nanometer length scales is heating by high-power pulsed or modulated lasers with low duty cycle.

Keblinski, Pawel; Cahill, David G.; Bodapati, Arun; Sullivan, Charles R.; Taton, T. Andrew

2006-09-01

19

An Efficient Localized Radial Basis Function Meshless Method for Fluid Flow and Conjugate Heat Transfer  

Microsoft Academic Search

A localized radial basis function (RBF) meshless method is developed for coupled viscous fluid flow and convective heat transfer problems. The method is based on new localized radial-basis function (RBF) expansions using Hardy Multiquadrics for the sought-after unknowns. An efficient set of formulae are derived to compute the RBF interpolation in terms of vector products thus providing a substantial computational

Eduardo Divo; Alain J. Kassab

2007-01-01

20

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

21

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

22

Global and local joule heating effects seen by DE 2  

Microsoft Academic Search

In the altitude region between 350 and 550 km, variations in the ion temperature principally reflect similar variations in the local frictional heating produced by a velocity difference between the ions and the neutrals. Here the authors show the distribution of the ion temperature in this altitude region and discuss its attributes in relation to previous work on local Joule

R.A. Heelis; W. R. Coley

1988-01-01

23

Global and local Joule heating effects seen by DE 2  

NASA Technical Reports Server (NTRS)

In the altitude region between 350 and 550 km, variations in the ion temperature principally reflect similar variations in the local frictional heating produced by a velocity difference between the ions and the neutrals. Here, the distribution of the ion temperature in this altitude region is shown, and its attributes in relation to previous work on local Joule heating rates are discussed. In addition to the ion temperature, instrumentation on the DE 2 satellite also provides a measure of the ion velocity vector representative of the total electric field. From this information, the local Joule heating rate is derived. From an estimate of the height-integrated Pedersen conductivity it is also possible to estimate the global (height-integrated) Joule heating rate. Here, the differences and relationships between these various parameters are described.

Heelis, R. A.; Coley, W. R.

1988-01-01

24

Creation of skyrmions and antiskyrmions by local heating.  

PubMed

Heating a system usually increases entropy and destroys order. However, there are also cases where heating gives a system the energy to overcome the potential barrier to reach a state with a nontrivial ordered pattern. Whether heating can manipulate the topological nature of the system is especially important. Here, we theoretically show by microsimulation that local heating can create topological magnetic textures, skyrmions, in a ferromagnetic background of chiral magnets and dipolar magnets. The resulting states depend sharply on intensity and spot size of heating, as well as the interaction to stabilize the skyrmions. Typically, the creation process is completed within 0.1?ns and 10?nm at the shortest time and smallest size, and these values can be longer and larger according to the choice of system. This finding will lead to the creation of skyrmions at will, which constitutes an important step towards their application to memory devices. PMID:25322803

Koshibae, Wataru; Nagaosa, Naoto

2014-01-01

25

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

26

Local cloning of two product states  

E-print Network

Local quantum operations and classical communication (LOCC) put considerable constraints on many quantum information processing tasks such as cloning and discrimination. Surprisingly however, discrimination of any two pure states survives such constraints in some sense. In this paper, we show that cloning is not that lucky; namely, conclusive LOCC cloning of two product states is strictly less efficient than global cloning.

Zhengfeng Ji; Yuan Feng; Mingsheng Ying

2005-01-17

27

TRANSLATION AND THE PRODUCTION OF LOCAL LITERATURE  

Microsoft Academic Search

This article looks at Taiwan's appropriation of literary modernism and the novelist Wang Chen-ho's writing, seeking to understand the mode of translation in the production of local literature. Wang's writing demonstrates a peculiar blending of heterogeneous languages. Straddling multiple linguistic and cultural realms, it can be argued that the author is a translator. Wang's composition evinces the practice of expressing

Yu-lin Lee

2006-01-01

28

Contribution of local background climate to urban heat islands  

NASA Astrophysics Data System (ADS)

The urban heat island (UHI) is one of the most significant climate modifications by anthropogenic activities. Despite active observational and modeling studies on the UHI, the primary mechanism of the UHI is still controversial due to the diversity of UHI concepts and the complexity of the mechanisms corresponding to the different UHIs. A study involving 68 selected cities over North America is conducted. Using 9-year MODIS products and a 10-year CLM (community land-surface model) simulation, we studied two types of UHI: surface UHI (skin temperature defined UHI) and air UHI (screen height air temperature defined UHI). Results show that the physics of daytime UHI and nighttime UHI are asymmetric. In the context of climatology, the annual mean precipitation of the cities (a proxy of the local background climate) is a strong control of both surface UHI and air UHI at daytime; while nighttime UHI is largely determined by the city morphology. Results show that the annual mean precipitation explains 46% of the spatial variation of the MODIS-derived daytime surface UHI and 66% of the CLM modeled air UHI. Precipitation exerts opposite controls on surface UHI and air UHI because of the difference in underlying mechanism of the two UHIs. A factorization of surface UHI using the CLM modeled data demonstrates the relative contribution of different factors to UHI.

Zhao, L.; Lee, X.

2013-12-01

29

District heating. Section 2: Products and services  

SciTech Connect

This is a directory of companies providing products and services in the area of district heating. The subheadings of the directory include developers and owner operators, equipment manufacturers, measuring instruments and controls, consulting services, engineering and construction, operation and maintenance, project management, repair, and financial and legal services.

Not Available

1991-12-01

30

Original Research Measuring Local RF Heating in MRI: Simulating  

E-print Network

Original Research Measuring Local RF Heating in MRI: Simulating Perfusion in a Perfusionless specific absorption rate (SAR) in phantom studies (14,15) rather than temperature change. Mea- surements of SAR, which is proportional to the initial rate of temperature increase, are much less susceptible 1

Atalar, Ergin

31

Localized annealing of polysilicon microstructures by inductively heated ferromagnetic films  

Microsoft Academic Search

The monolithic integration of dissimilar microsystems is often limited by conflicts in thermal budget. One of the most prevalent examples is the fabrication of active micro-electromechanical systems (MEMS), as structural films utilized for surface micromachining such as polysilicon typically require processing at temperatures unsuitable for microelectronic circuitry. A localized annealing process could provide for the post-deposition heat treatment of integrated

Melissa L. Trombley

2007-01-01

32

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

33

Convection calibration method for local heat flux gages  

SciTech Connect

An apparatus for calibrating local heat flux gages in convective air flows is described. Heat transfer from a ''hot'' gage to a ''cold'' fluid was measured using a guarded hot-plate technique. The system was used to calibrate Gardon-type circular foil heat flux gates of 1/8 in. and 1/16 in. outer diameters. The reslts indicate that the calibration curves are nonlinear, which is different from the linear calibration obtained using the standard radiation technique. The degree of nonlinearity matches the analysis which accounts for the effect of the temperature distribution in the gage foil. The effect of this temperature distribution can be neglected in the standard radiation calibration but is often significant in convection applications. These results emphasize the importance of calibrating heat flux gates in thermal environments similar to those in which they will be used.

Borell, G.J.; Diller, T.E.

1987-02-01

34

Local heating, but not indirect whole body heating, increases human skeletal muscle blood flow  

PubMed Central

For decades it was believed that direct and indirect heating (the latter of which elevates blood and core temperatures without directly heating the area being evaluated) increases skin but not skeletal muscle blood flow. Recent results, however, suggest that passive heating of the leg may increase muscle blood flow. Using the technique of positron-emission tomography, the present study tested the hypothesis that both direct and indirect heating increases muscle blood flow. Calf muscle and skin blood flows were evaluated from eight subjects during normothermic baseline, during local heating of the right calf [only the right calf was exposed to the heating source (water-perfused suit)], and during indirect whole body heat stress in which the left calf was not exposed to the heating source. Local heating increased intramuscular temperature of the right calf from 33.4 ± 1.0°C to 37.4 ± 0.8°C, without changing intestinal temperature. This stimulus increased muscle blood flow from 1.4 ± 0.5 to 2.3 ± 1.2 ml·100 g?1·min?1 (P < 0.05), whereas skin blood flow under the heating source increased from 0.7 ± 0.3 to 5.5 ± 1.5 ml·100 g?1·min?1 (P < 0.01). While whole body heat stress increased intestinal temperature by ?1°C, muscle blood flow in the calf that was not directly exposed to the water-perfused suit (i.e., indirect heating) did not increase during the whole body heat stress (normothermia: 1.6 ± 0.5 ml·100 g?1·min?1; heat stress: 1.7 ± 0.3 ml·100 g?1·min?1; P = 0.87). Whole body heating, however, reflexively increased calf skin blood flow (to 4.0 ± 1.5 ml·100 g?1·min?1) in the area not exposed to the water-perfused suit. These data show that local, but not indirect, heating increases calf skeletal muscle blood flow in humans. These results have important implications toward the reconsideration of previously accepted blood flow distribution during whole body heat stress. PMID:21680875

Heinonen, Ilkka; Brothers, R. Matthew; Kemppainen, Jukka; Knuuti, Juhani; Kalliokoski, Kari K.

2011-01-01

35

Proposal for a local heating driven spin current generator  

NASA Astrophysics Data System (ADS)

We propose a two-terminal spin-orbit interferometer with a hot molecule inserted in one of its arms to generate pure spin currents. Local heating is achieved by coupling the vibrational modes of the molecule to a third (phononic) reservoir. We show that this spin caloritronic effect is due to the combined influence of spin-dependent wave interference and inelastic scattering. Remarkably, the device converts heat flow into spin-polarized current even without applying any voltage or temperature difference to the electronic terminals.

Hwang, Sun-Yong; Soo Lim, Jong; López, Rosa; Lee, Minchul; Sánchez, David

2013-10-01

36

Constraints on Crustal Heat Production from Heat Flow Data  

NASA Astrophysics Data System (ADS)

The continental crust is an important repository of highly incompatible elements such as uranium and thorium. Exactly how much it contains is a key issue for the thermal regime of continents and for understanding how the Earth's mantle has evolved through geological time due to crust extraction. Recent estimates of the average uranium, thorium, and potassium concentrations in the continental crust vary by almost a factor of 2 (Wedepohl, 1995;Rudnick and Fountain, 1995; Taylor and McLennan, 1995; see also Chapter 3.01). These estimates are based on different assumptions regarding crustal structure and rely on different types of crustal samples, ranging from xenoliths to shales. They require an extrapolation in scale from tiny specimens to the whole crust of a geological province. Uranium and thorium tend to be located in accessory minerals and on grain boundaries, which are not related simply to bulk chemical composition. Thus, their concentrations vary on the scale of a petrological thin section, a hand sample, an outcrop, and a whole massif. In a geological province, abundant rocks such as gneisses and metasedimentary rocks are usually under-studied because of their complex origin and metamorphic history. A final difficulty is to evaluate the composition of intermediate and lower crustal levels, which are as heterogeneous as the shallow ones (e.g., Fountain and Salisbury, 1981; Clowes et al., 1992).Independent estimates of the amount of uranium and thorium in the continental crust can be obtained from heat flow data. The energy produced by the decay of these radioactive elements accounts for a large fraction of the heat flow at the surface of continents (Birch, 1954; Wasserburg et al., 1964; Clark and Ringwood, 1964; Sclater et al., 1980; Taylor and McLennan, 1995). This may be the only case where geophysical data bear directly on geochemical budgets. Since the mid-1970s, there has been much progress in our understanding of continental heat flow. The relationship between variations in heat flow and crustal heat production has been investigated systematically ( England et al., 1980; Jaupart, 1983a; Vasseur and Singh, 1986; Ketcham, 1996; Jaupart and Mareschal, 1999). Heat flow determinations on continents have been multiplied by almost a factor of 10 between the compilations by Jessop et al. (1976) and Pollack et al. (1993). Since the last compilation, a large number of high-quality data have been obtained for the poorly studied Precambrian Shield areas of Canada and India ( Mareschal et al., 2000a, b; Roy and Rao, 2000; Rolandone et al., 2002; Lewis et al., 2003).

Jaupart, C.; Mareschal, J.-C.

2003-12-01

37

Local and distant products from modularity.  

PubMed

In this study, the local and distant distribution of solid and soluble products of corrosion from the head and neck junction of modular femoral total hip prosthetic components were characterized. Particulate corrosion products from retrieved implants and surrounding tissues were analyzed. Serum transport and urinary excretion of metal was measured in correlation with the degree of corrosion at the head and neck junction. Particles of metal oxides, metal chlorides, and chromium phosphate corrosion products were identified on implants of 10 designs from 6 manufacturers. The most abundant solid corrosion product on the implant and within the periprosthetic tissues (size range, < 1-200 micrometers) was an amorphous chromium orthophosphate hydrate-rich material. Serum cobalt and urine chromium concentrations were elevated significantly in patients with implants that had moderate to severe corrosion in comparison with those with no to mild corrosion. Solid corrosion products from modular femoral stems may accelerate articular wear via a 3-body mechanism. Phagocytosable particles of these corrosion products may stimulate macrophage-mediated periprosthetic bone loss. Systemic dissemination of metallic corrosion products raises the issue of systemic toxicity; however, no overt evidence of metal toxicity was observed in this study. PMID:7554654

Jacobs, J J; Urban, R M; Gilbert, J L; Skipor, A K; Black, J; Jasty, M; Galante, J O

1995-10-01

38

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

39

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

40

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

41

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.

Del-Castillo-Negrete, Diego B [ORNL; Chacon, Luis [ORNL

2011-01-01

42

Local Heat Transfer for Finned-Tube Heat Exchangers using Oval Tubes  

SciTech Connect

This paper presents the results of an experimental study of forced convection heat transfer in a narrow rectangular duct fitted with either a circular tube or an elliptical tube in crossflow. The duct was designed to simulate a single passage in a fin-tube heat exchanger. Heat transfer measurements were obtained using a transient technique in which a heated airflow is suddenly introduced to the test section. High-resolution local fin-surface temperature distributions were obtained at several times after initiation of the transient using an imaging infrared camera. Corresponding local fin-surface heat transfer coefficient distributions were then calculated from a locally applied one-dimensional semi-infinite inverse heat conduction model. Heat transfer results were obtained over an airflow rate ranging from 1.56 x 10-3 to 15.6 x 10-3 kg/s. These flow rates correspond to a duct-height Reynolds number range of 630 – 6300 with a duct height of 1.106 cm and a duct width-toheight ratio, W/H, of 11.25. The test cylinder was sized such that the diameter-to-duct height ratio, D/H is 5. The elliptical tube had an aspect ratio of 3:1 and a/H equal to 4.33. Results presented in this paper reveal visual and quantitative details of local fin-surface heat transfer distributions in the vicinity of circular and oval tubes and their relationship to the complex horseshoe vortex system that forms in the flow stagnation region. Fin surface stagnation-region Nusselt numbers are shown to be proportional to the square-root of Reynolds number.

O'Brien, James Edward; Sohal, Manohar Singh

2000-08-01

43

Local Heat Flux Measurements with Single Element Coaxial Injectors  

NASA Technical Reports Server (NTRS)

To support the mission for the NASA Vision for Space Exploration, 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, as well as for small thrusters with few elements in the injector. In this program, single element and three-element injectors were hot-fire tested with liquid oxygen and ambient temperature 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. Injectors were tested with shear coaxial and swirl coaxial elements, including recessed, flush and scarfed oxidizer post configurations, and concentric and non-concentric fuel annuli. This paper includes general descriptions of the experimental hardware, instrumentation, and results of the hot-fire testing for three of the single element injectors - recessed-post shear coaxial with concentric fuel, flush-post swirl coaxial with concentric fuel, and scarfed-post swirl coaxial with concentric fuel. Detailed geometry and test results will be published elsewhere to provide well-defined data sets for injector development and model validatation.

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

2006-01-01

44

Localized heating during serrated plastic flow in bulk metallic glasses  

Microsoft Academic Search

We have studied the serrated plastic flow observed in Zr40Ti14Ni10Cu12Be24 and Pd40Ni40P20 bulk metallic glass alloys tested in uniaxial compression. Quantitative measurements with sufficient temporal resolution to record the fine-scale structure of the data are reported. These data are used to predict temperature increases in single shear bands due to local adiabatic heating caused by the work done on the

Wendelin J Wright; Ricardo B Schwarz; William D Nix

2001-01-01

45

Localized annealing of polysilicon microstructures by inductively heated ferromagnetic films  

NASA Astrophysics Data System (ADS)

The monolithic integration of dissimilar microsystems is often limited by conflicts in thermal budget. One of the most prevalent examples is the fabrication of active micro-electromechanical systems (MEMS), as structural films utilized for surface micromachining such as polysilicon typically require processing at temperatures unsuitable for microelectronic circuitry. A localized annealing process could provide for the post-deposition heat treatment of integrated structures without compromising active devices. This dissertation presents a new microfabrication technology based on the inductive heating of ferromagnetic films patterned to define regions for heat treatment. Support is provided through theory, finite-element modeling, and experimentation, concluding with the demonstration of inductive annealing on polysilicon inertial sensing structures. Though still in its infancy, the results confirm the technology to be a viable option for integrated MEMS as well as any microsystem fabrication process requiring a thermal gradient.

Trombley, Melissa L.

46

Relaxation of geothermal-reservoir stresses induced by heat production  

SciTech Connect

Fifteen million kWh of thermal energy were produced during 281 days of operation of the hot dry rock (HDR) geothermal reservoir at Fenton Hill, New Mexico. Following this heat production the thermal stresses and strains so induced were partially released by a short, 7-h pressurization of the reservoir above the local tectonic confining stress. Following the partial stress release, it was found that the resistance to water flow through the reservoir was decreased by 37%, and that the reservoir volume, as measured by tracer studies, increased by 43%. Microseismic events recorded with geophones in two deep wells at positions within a few hundred meters of the reservoir were concentrated in those regions of the reservoir most affected by thermal depletion. These events define a reservoir region and size in qualitative agreement with estimates based upon heat production modeling.

Murphy, H.; Aamodt, R.; Fisher, H.

1981-08-01

47

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

48

Localized, plasmon-mediated heating from embedded nanoparticles in nanocomposites  

NASA Astrophysics Data System (ADS)

Metallic nanoparticles exhibit a surface plasmon resonance which, when excited with visible light, results in a dramatic increase in the nanoparticle temperature. Previously such localized heating has been primarily employed in biomedical research and other experiments involving aqueous environments. In this work, we investigated use of the nanoparticles in solid phase to re-shape, bond, melt, and otherwise process nanofibrous mats of ˜200 nm diameter nanofibers doped with ˜80 nm spherical gold nanoparticles. Under low light intensities (100 mW/cm^2 @ 532 nm) and dilute nanoparticle loading (˜0.15% volume fraction), irradiation of a few minutes melted nanofibrous mats of poly (ethylene oxide) (Tm = 65 degree C). Control samples without gold nanoparticles displayed no melting. Because the heat is generated from within the material and only at the nanoparticle locations, this technique enables true nanoprocessing -- the non-contact, controlled application of heat at specific nano-sized locations within a material to effect desired local changes. Funded by CMMI-0829379.

Maity, Somsubhra; Downen, Lori; Bochinski, Jason; Clarke, Laura

2010-03-01

49

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

50

Feedbacks of biotically induced radiative heating on upper-ocean heat budget, circulation, and biological production in a coupled ecosystem-circulation model  

Microsoft Academic Search

A coupled ecosystem-circulation model of the North Atlantic Ocean is used to investigate the impact of radiative heating by biotically induced absorption of solar radiation on the ocean's heat budget, on water column stability and circulation, and on biological production itself. For fixed atmospheric conditions, the local sensitivity of the nonsolar heat flux to changes in sea surface temperature leads

Andreas Oschlies

2004-01-01

51

Localized Joule heating produced by ion current focusing through micron-size holes  

E-print Network

Localized Joule heating produced by ion current focusing through micron-size holes V. Viasnoff,1,a is discussed. © 2010 American Institute of Physics. doi:10.1063/1.3399315 The creation of local heat sources diffusion of heat in water. Several solutions were proposed, such as heating micro/nanoparticles1

52

Transient response to localized episodic heating in the tropics  

NASA Technical Reports Server (NTRS)

It is generally recognized that equatorial disturbances in the lower stratosphere are excited by convective latent heat release associated with the Internal Tropical Convergence Zone (ITCZ). Recently, attention has also focused on tropical convection with regard to extratropical teleconnection patterns. Unlike equatorial waves which are trapped about the equator but propagate vertically, the latter extend well out of the tropics but are barotropic. They have been most widely discussed in connection with long-term climatological features. Both types of disturbances have been examined largely from the standpoint of steady monochromatic forcing, in the latter case zero frequency or time-mean heating. However, tropical convection as revealed by recent geostationary satellite imagery is anything but regular, surely not steady. Much of the heating variance is concentrated spatially within three localized convective centers: Indonesia, the Amazon, and the Congo. Convective activity within these regions undergoes an irregular evolution over the span of a couple of days. It involves a rather broad spectrum of spatial and temporal scales. The analysis of cloud brightness over the Eastern Atlantic and Africa suggests a characteristic time scale of 3-4 days and correlations scales in latitude and longitude of approximately 30 deg.

Salby, M. L.; Garcia, R. R.

1985-01-01

53

Transient response to localized episodic heating in the tropics  

NASA Astrophysics Data System (ADS)

It is generally recognized that equatorial disturbances in the lower stratosphere are excited by convective latent heat release associated with the Internal Tropical Convergence Zone (ITCZ). Recently, attention has also focused on tropical convection with regard to extratropical teleconnection patterns. Unlike equatorial waves which are trapped about the equator but propagate vertically, the latter extend well out of the tropics but are barotropic. They have been most widely discussed in connection with long-term climatological features. Both types of disturbances have been examined largely from the standpoint of steady monochromatic forcing, in the latter case zero frequency or time-mean heating. However, tropical convection as revealed by recent geostationary satellite imagery is anything but regular, surely not steady. Much of the heating variance is concentrated spatially within three localized convective centers: Indonesia, the Amazon, and the Congo. Convective activity within these regions undergoes an irregular evolution over the span of a couple of days. It involves a rather broad spectrum of spatial and temporal scales. The analysis of cloud brightness over the Eastern Atlantic and Africa suggests a characteristic time scale of 3-4 days and correlations scales in latitude and longitude of approximately 30 deg.

Salby, M. L.; Garcia, R. R.

1985-12-01

54

Thermal balance and quantum heat transport in nanostructures thermalized by local Langevin heat baths  

NASA Astrophysics Data System (ADS)

Modeling of thermal transport in practical nanostructures requires making tradeoffs between the size of the system and the completeness of the model. We study quantum heat transfer in a self-consistent thermal bath setup consisting of two lead regions connected by a center region. Atoms both in the leads and in the center region are coupled to quantum Langevin heat baths that mimic the damping and dephasing of phonon waves by anharmonic scattering. This approach treats the leads and the center region on the same footing and thereby allows for a simple and physically transparent thermalization of the system, enabling also perfect acoustic matching between the leads and the center region. Increasing the strength of the coupling reduces the mean-free path of phonons and gradually shifts phonon transport from ballistic regime to diffusive regime. In the center region, the bath temperatures are determined self-consistently from the requirement of zero net energy exchange between the local heat bath and each atom. By solving the stochastic equations of motion in frequency space and averaging over noise using the general fluctuation-dissipation relation derived by Dhar and Roy [J. Stat. Phys.JSTPBS0022-471510.1007/s10955-006-9235-3 125, 801 (2006)], we derive the formula for thermal current, which contains the Caroli formula for phonon transmission function and reduces to the Landauer-Büttiker formula in the limit of vanishing coupling to local heat baths. We prove that the bath temperatures measure local kinetic energy and can, therefore, be interpreted as true atomic temperatures. In a setup where phonon reflections are eliminated, the Boltzmann transport equation under gray approximation with full phonon dispersion is shown to be equivalent to the self-consistent heat bath model. We also study thermal transport through two-dimensional constrictions in square lattice and graphene and discuss the differences between the exact solution and linear approximations.

Sääskilahti, K.; Oksanen, J.; Tulkki, J.

2013-07-01

55

Thermal balance and quantum heat transport in nanostructures thermalized by local Langevin heat baths.  

PubMed

Modeling of thermal transport in practical nanostructures requires making tradeoffs between the size of the system and the completeness of the model. We study quantum heat transfer in a self-consistent thermal bath setup consisting of two lead regions connected by a center region. Atoms both in the leads and in the center region are coupled to quantum Langevin heat baths that mimic the damping and dephasing of phonon waves by anharmonic scattering. This approach treats the leads and the center region on the same footing and thereby allows for a simple and physically transparent thermalization of the system, enabling also perfect acoustic matching between the leads and the center region. Increasing the strength of the coupling reduces the mean-free path of phonons and gradually shifts phonon transport from ballistic regime to diffusive regime. In the center region, the bath temperatures are determined self-consistently from the requirement of zero net energy exchange between the local heat bath and each atom. By solving the stochastic equations of motion in frequency space and averaging over noise using the general fluctuation-dissipation relation derived by Dhar and Roy [J. Stat. Phys. 125, 801 (2006)], we derive the formula for thermal current, which contains the Caroli formula for phonon transmission function and reduces to the Landauer-Büttiker formula in the limit of vanishing coupling to local heat baths. We prove that the bath temperatures measure local kinetic energy and can, therefore, be interpreted as true atomic temperatures. In a setup where phonon reflections are eliminated, the Boltzmann transport equation under gray approximation with full phonon dispersion is shown to be equivalent to the self-consistent heat bath model. We also study thermal transport through two-dimensional constrictions in square lattice and graphene and discuss the differences between the exact solution and linear approximations. PMID:23944435

Sääskilahti, K; Oksanen, J; Tulkki, J

2013-07-01

56

Localizing heat-generating defects using fluorescent microthermal imaging  

SciTech Connect

Fluorescent microthermal imaging (FMI) involves coating a sample surface with a thin fluorescent film that, upon exposure to UV light source, emits temperature-dependent fluorescence. The principle behind FMI was thoroughly reviewed at the ISTFA in 1994. In two recent publications, we identified several factors in film preparation and data processing that dramatically improved the thermal resolution and sensitivity of FMI. These factors include signal averaging, the use of base mixture films, film stabilization and film curing. These findings significantly enhance the capability of FMI as a failure analysis tool. In this paper, we show several examples that use FMI to quickly localize heat-generating defects (``hot spots``). When used with other failure analysis techniques such as focused ion beam (FIB) cross sectioning and scanning electron microscope (SEM) imaging, we demonstrate that FMI is a powerful tool to efficiently identify the root cause of failures in complex ICs. In addition to defect localization, we use a failing IC to I determine the sensitivity of FMI (i.e., the lowest power that can be detected) in an ideal situation where the defects are very localized and near the surface.

Tangyunyong, P.; Liang, A.Y.; Righter, A.W.; Barton, D.L.; Soden, J.M.

1996-10-01

57

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

58

Homogeneous Thermal Cloak with Constant Conductivity and Tunable Heat Localization  

NASA Astrophysics Data System (ADS)

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.

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

2013-04-01

59

Heat production in an Archean crustal profile and implications for heat flow and mobilization of heat-producing elements  

NASA Technical Reports Server (NTRS)

Concentrations of heat producing elements (Th, U, and K) in 58 samples representative of the main lithologies in a 100-km transect of the Superior Province of the Canadian Shield have been obtained. The relatively large variation in heat production found among the silicic plutonic rocks is shown to correlate with modal abundances of accessory minerals, and these variations are interpreted as premetamorphic. The present data suggest fundamental differences in crustal radioactivity distributions between granitic and more mafic terrains, and indicate that a previously determined apparently linear heat flow-heat production relationship for the Kapuskasing area does not relate to the distribution of heat production with depth.

Ashwal, L. D.; Morgan, P.; Kelley, S. A.; Percival, J. A.

1987-01-01

60

Local algorithms for the prime factorization of strong product graphs  

E-print Network

Local algorithms for the prime factorization of strong product graphs Marc Hellmuth, Wilfried-linear algorithm for the prime factorization of "locally unrefined graphs with respect to the strong product the product structure completely, modifying a graph with many factors to a prime one [2, 9]. The recognition

Stadler, Peter F.

61

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 of the measured Nusselt number (nor- malized heat flux), Nu(Ra,Pr), as a function of the two experimental control of the convection cell. Direct measurements of the local convective heat flux, therefore, become essential

Tong, Penger

62

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

E-print Network

that three main possible mechanisms could drive ion outflow: frictional (Joule) ion heating, thermal electron, and local ion heating in the midaltitude cleft//low-latitude boundary layer observed by Cluster Y. V+ and H+ ion heating and with localized extra low frequency (ELF) (1­10 Hz) magnetic field wave power

Lotko, William

63

Numerical investigation of conjugate heat transfer in a local working area in conditions of its radiant heating  

NASA Astrophysics Data System (ADS)

Mathematical modeling of unsteady conjugate heat transfer in a closed rectangular area with a local heat-conducting object in a gas cavity in conditions of radiative heat supply is conducted. Fields of temperatures and stream functions, illustrating the influence of Grashof number on the character of heat transfer are formulated. The dependence of average Nusselt number from time at different Grashof numbers is given. The influence of heat-conductive object on the intensity of heat transfer in under study solution domain is shown.

Nee, A.; Nagornova, T.

2014-10-01

64

An evaluation of local heating as a means of fuel evaporation for gasoline engines  

SciTech Connect

The technique of evaporating fuel by localized heating before entering the intake manifold is evaluated as a means of improving A/F ratio control. Techniques currently in use are briefly discussed, and attempts to analyze fuel evaporation in S.I. engines are reviewed. A test fixture which includes all the essential features of production feasible hardware is used to develop a basis of understanding for the evaporation process. Tests are conducted on a flow bench using water as ''fuel,'' and on an engine using isooctane and gasoline. A heat-mass transfer analogy is described and used to predict evaporation rates for water and isooctane. Predicted and measured rates are compared for both bench and engine tests. Engine tests with gasoline show the ability of the test configuration to evaporate all part throttle fuel flow before it enters the intake manifold. Results are presented which show the ability of local heating to reduce A/F excursions on the 1.6 Liter engine by 80% over the ambient temperature range of 0/sup 0/F to 70/sup 0/F. Results showing the elimination of cylinder to cylinder A/F maldistribution are presented, and recommended operating temperatures and heat inputs for engine operation are also presented.

Aquino, C.; Plensdorf, W.D.

1986-01-01

65

Natural convection in enclosures with localized heating from below and symmetrical cooling from sides  

Microsoft Academic Search

Natural convection of air in a two-dimensional, rectangular enclosure with localized heating from below and symmetrical cooling from the sides has been numerically investigated. Localized heating is simulated by a centrally located heat source on the bottom wall, and four different values of the dimensionless heat source length, 1\\/5, 2\\/5, 3\\/5 and 4\\/5 are considered. Solutions are obtained for Rayleigh

Orhan Aydin; Wen-Jei Yang

2000-01-01

66

Thermal balance and quantum heat transport in nanostructures thermalized by local Langevin heat baths  

E-print Network

Modeling of thermal transport in practical nanostructures requires making trade-offs between the size of the system and the completeness of the model. We study quantum heat transfer in a self-consistent thermal bath setup consisting of two lead regions connected by a center region. Atoms both in the leads and in the center region are coupled to quantum Langevin heat baths that mimic the damping and dephasing of phonon waves by anharmonic scattering. Increasing the strength of the coupling reduces the mean free path of phonons and gradually shifts phonon transport from ballistic regime to diffusive regime. In the center region, the bath temperatures are determined self-consistently from the requirement of zero net energy exchange between the local heat bath and each atom. By solving the stochastic equations of motion in frequency space and averaging over noise, we derive the formula for thermal current, which contains the Caroli formula for phonon transmission function and reduces to the Landauer-B\\"uttiker fo...

Sääskilahti, K; Tulkki, J

2013-01-01

67

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

68

Marketing Locally Grown Food Products in Globally Branded Restaurants  

Microsoft Academic Search

This research study measures the perception patrons of a McDonald's restaurant for locally grown food products used in standard menu items. A survey questionnaire attempts to determine differences in consumer knowledge regarding the use of local Swiss food products and whether an increase in frequency of patronizing the restaurant will occur as a result of this program. The issue of

Michael Vieregge; Nancy Scanlon; James Huss

2007-01-01

69

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

70

Forced convection in a porous channel with localized heat sources  

Microsoft Academic Search

A numerical study is performed to analyze steady laminar forced convection in a channel filled with a fluid-saturated porous medium and containing discrete heat sources on the bottom wall. Hydrodynamic and heat transfer results are reported for two configurations: (1) a fully porous channel; and (2) a partially porous channel, which contains porous layers above the heat sources and is

A. Hadim

1994-01-01

71

Dissipation and entropy production in deterministic heat conduction of quasi-one-dimensional systems.  

PubMed

We explore the consequences of a deterministic microscopic thermostat-reservoir contact mechanism. With different temperature reservoirs at each end of a two-dimensional system, a heat current is produced and the system has an anomalous thermal conductivity. The microscopic form for the local heat flux vector is derived and both the kinetic and potential contributions are calculated. The total heat flux vector is shown to satisfy the continuity equation. The properties of this nonequilibrium steady state are studied as functions of system size and temperature gradient, identifying key scaling relations for the local fluid properties and separating bulk and boundary effects. The local entropy density calculated from the local equilibrium distribution is shown to be a very good approximation to the entropy density calculated directly from the velocity distribution even for systems that are far from equilibrium. The dissipation and kinetic entropy production and flux are compared quantitatively and the differing mechanisms discussed within the Bhatnagar-Gross-Krook approximation. For equal-temperature reservoirs the entropy production near the reservoir walls is shown to be proportional to the local phase space contraction calculated from the tangent space dynamics. However, for unequal temperatures, the connection between local entropy production and local phase space contraction is more complicated. PMID:23848664

Morriss, Gary P; Truant, Daniel P

2013-06-01

72

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

73

Radiative heat transfer in nonisothermal combustion products  

NASA Astrophysics Data System (ADS)

Radiative heat transfer plays a significant and sometimes dominant role within combustion systems. Heat flux measurements in such systems are sometimes economically disadvantaged and difficult, if not impractical to perform. To demonstrate a feasible alternative, a simplified numerical model using total transmittance data, TTNH, was developed for predicting the heat flux from nonisothermal combustion systems containing variable concentrations of water vapor, carbon dioxide, and methane. Total and spectral experimental measurements were carried out, to test the numerical model, using nonisothermal mixtures of water vapor/carbon dioxide and methane/ethene, and using isothermal mixtures of methane and ethene. In general, the TTNH model was found to be reliable to predict the total emitted energy by nonisothermal mixtures of carbon dioxide and water vapor within 10%. However, the model was found not reliable to predict the theoretical emittance of methane.

Hamdan, M. A.

1985-12-01

74

Shear heating induced lithospheric-scale localization: Does it result in subduction?  

E-print Network

Shear heating induced lithospheric-scale localization: Does it result in subduction? Marcel-tectonics mode, the question on how to ``break'' lithospheric plates and initiate subduction remains a matter of debate. Here we focus on shear heating as a potential mechanism to cause lithospheric shear localization

Kaus, Boris

75

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

76

Heat shock treatment improves Trametes versicolor laccase production.  

PubMed

An efficient heat shock strategy has been developed to improve laccase production in submerged Trametes versicolor cultures. The optimized heat shock strategy consists of subjecting T. versicolor mycelial pellets to three heat shock treatments at 45 °C for 45 min, starting at culture day 0, with a 24-h interval between treatments. Laccase production increased by more than 1.6-fold relative to the control in both flasks and a 5-L bioreactor because the expression of the laccase gene was enhanced by heat shock induction. The present work demonstrates that heat shock induction is a promising method because it both improves fungal laccase production and has a good potential in industrial application. PMID:22733235

Wang, Feng; Guo, Chen; Wei, Tao; Zhang, Tian; Liu, Chun-Zhao

2012-09-01

77

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

Microsoft Academic Search

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

H. Taha

2007-01-01

78

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

79

Metabolic heat production, heat loss and the circadian rhythm of body temperature in the rat.  

PubMed

Metabolic heat production (calculated from oxygen consumption), dry heat loss (measured in a calorimeter) and body temperature (measured by telemetry) were recorded simultaneously at 6 min intervals over five consecutive days in rats maintained in constant darkness. Robust circadian rhythmicity (confirmed by chi square periodogram analysis) was observed in all three variables. The rhythm of heat production was phase-advanced by about half an hour in relation to the body temperature rhythm, whereas the rhythm of heat loss was phase-delayed by about half an hour. The balance of heat production and heat loss exhibited a daily oscillation 180 deg out of phase with the oscillation in body temperature. Computations indicated that the amount of heat associated with the generation of the body temperature rhythm (1.6 kJ) corresponds to less than 1 % of the total daily energy budget (172 kJ) in this species. Because of the small magnitude of the fraction of heat balance associated with the body temperature rhythm, it is likely that the daily oscillation in heat balance has a very slow effect on body temperature, thus accounting for the 180 deg phase difference between the rhythms of heat balance and body temperature. PMID:12719767

Refinetti, Roberto

2003-05-01

80

Radiogenic heat production, thermal regime and evolution of continental crust  

NASA Astrophysics Data System (ADS)

Heat flow and heat production data complement seismic information and provide strong constraints on crustal composition, thickness and evolution. They have helped understand the nature of the Mohorovicic discontinuity and the variations in seismic velocities below the Moho. Notably, heat flow studies have delineated the vertical distribution of heat producing elements throughout the crust and in the upper most mantle lithosphere. Analysis of global data sets on heat flow and crustal thickness demonstrate that there is no correlation between these two variables. This is due to the large spatial variations in crustal composition and heat production that exist within a single geological province. For a given crustal thickness, the Moho temperature varies within a wide range (? 300 K) depending on surface heat flux and crustal heat production. Thus one cannot use generic models based on a “type” crustal column to calculate crustal geotherms. In stable regions, lower crustal temperatures depend on the amount and vertical distribution of heat producing elements in the crust. These temperatures determine the conditions of crustal stability and impose a limit on the maximum thickness of a stabilized crust.

Mareschal, Jean-Claude; Jaupart, Claude

2013-12-01

81

Extraction of Natural Products Using Microwaves as a Heat Source  

Microsoft Academic Search

Microwave-assisted extraction is the process of using microwave energy to heat the moisture present in the plant material or solvents in contact in order to extract natural products from the plant materials. A typical microwave-assisted extraction is completed within few minutes with higher yield and less solvent consumption. This review gives a brief theoretical background of microwave heating along with

Meghal Desai; Jigisha Parikh; P. A. Parikh

2010-01-01

82

GREENHOUSE PRODUCTION OF BEDDING AND FOLIAGE PLANTS WITH INDUSTRIAL HEAT  

EPA Science Inventory

The report gives results of an evaluation of potentially beneficial uses of industrial waste heat for production of bedding and foliage plants, using conventionally and warm-water heated greenhouses in Fort Valley, GA. Each greenhouse was a plastic covered, 30 x 72-ft quonset. Th...

83

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

84

A New Model for Heat Flow in Extensional Basins: Estimating Radiogenic Heat Production  

Microsoft Academic Search

Radiogenic heat production (RHP) represents a significant fraction of surface heat flow, both on cratons and in sedimentary basins. RHP within continental crust—especially the upper crust—is high. RHP at any depth within the crust can be estimated as a function of crustal age. Mantle RHP, in contrast, is always low, contributing at most 1 to 2 mW\\/m2 to total heat

Douglas W. Waples

2002-01-01

85

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

86

Feasibility of local condom production examined.  

PubMed

Despite Africa being the world region worst affected by the HIV/AIDS pandemic, there is only 1 condom manufacturer on the continent, in Johannesburg. Hundreds of millions of condoms are donated and imported annually. For example, 500 million units were donated in 1996, of which 212 million came from the US Agency for International Development. A recently released study commissioned by the European Union's HIV/AIDS Program for Developing Countries determined that it would be technically viable to manufacture condoms in not only South Africa, but also in Mauritius, Cote d'Ivoire, and Kenya. All that is required is a factory, work force, water, and electricity, with the raw materials to be imported from Malaysia or Thailand regardless of where the factory is located. The financial returns of such an operation would depend upon the cost of labor, the type of factory and its output, and market demand. Benefits would include employment creation, potential exports, and foreign exchange savings. A typical condom plant, operating 24 hours a day with 2 production lines, can produce 160 million condom units per year. However, should such a factory be built and put into operation, managers must ensure that any condoms produced are of high quality. PMID:12295121

1999-01-01

87

Ruminant heat stress: effect on production and means of alleviation.  

PubMed

A review of the literature indicates heat stress generally causes lower milk production, decreased growth rate for cattle and lambs, but little effect on wool production. Breed and diet affects the degree of adverse response. Heat stress is caused primarily by high air temperature, but can be intensified by high humidity, thermal radiation and low air movement. Improving performance of animals under warm conditions involves breeding and management and modifying the environment. The former includes selection for heat tolerance, use of crossbred animals, diets with low heat increment in relation to energy for production and control of diseases and parasites. Environmental modifications may include provision of shades, use of water for evaporative cooling and increased air movement. PMID:6370944

Morrison, S R

1983-12-01

88

Energy production by local governments: An expanding role  

SciTech Connect

Alternative energy production by local governments is a strong indicator that technological change and organizational response go hand in hand. Based on a newly developed set of technologies for modern applications and a sharply revised set of legal and organizational conditions for the production and sale of energy, local governments in large numbers have taken risks, invested money, developed projects, and become interested in the larger economic and political issues shaping the nation's energy future. Although the energy production projects themselves have arisen, for the most part, as a natural outgrowth of traditional local government services, they have in virtually every case expanded the range of interests and concerns of local government into a wide variety of technical and legal areas that affect both public and private small power producers.

Tatum, J.S.; Bradshaw, T.K.

1986-01-01

89

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

90

Enthalphyand Heat Capacity of Several Candy Products.  

National Technical Information Service (NTIS)

Neither in the Soviet nor in the foreign literature are there at the present sufficient data on the thermophysical properties of candy products. The lack of such data makes it impossible to carry out thermal and technological computations with a sufficien...

A. Kovalev, I. Perelshtein

1972-01-01

91

Effects of electron beam local post-weld heat-treatment on the microstructure and properties of 30CrMnSiNi2A steel welded joints  

Microsoft Academic Search

To improve the microstructure and properties of electron beam welded joints, vacuum or furnace whole post-weld heat-treatment (FWPWHT) should usually be carried out. Electron beam local post-weld heat-treatment (EBLPWHT) is a quite new heat-treatment procedure that provides the advantages of high precision, flexibility and efficiency, energy saving, and higher productivity. In this paper, the microstructure, mechanical properties, fracture toughness and

F. R. Chen; L. X. Huo; Y. F. Zhang; L. Zhang; F. J. Liu; G. Chen

2002-01-01

92

Noise-induced local heatings in beam irradiation  

Microsoft Academic Search

In every kind of beam irradiation, a part of the incident power is eventually dissipated within the irradiated sample, leading to a heating which has to be evaluated, in order to be sure that thermal effects (such as diffusion, phase transitions, etc.) are under control. Expanding on usual thermal estimations based upon the coherent part of the incident power, we

G. Plumereau; P. Aranda; P. Ailloud; P. Berger; D. Boutard; F. Ladieu

1999-01-01

93

Local aerodynamics and heat transfer in beds of packed spheres, simulating spherical fuel elements  

SciTech Connect

An experimental study of the three-dimensional distribution of pressure coefficients and the coefficients of local heat transfer in beds of staggered spheres proved that the local characteristics depend strongly on the value of design factor kappa and on the location of the sphere within the packed bed. It was proved that largest changes in the local characteristics occur in regions of contact between the spheres and the wall, and also in points of boundary-layer separation. The effect of these contacts manifests itself over a solid angle of about 80/sup 0/. The nonuniformity in the distribution of local heat transfer coefficients decreases with increasing kappa and with flow stabilization.

Zadanavicius, G.V.; Margis, L.A.

1983-03-01

94

Hydraulic drag and local heat transfer with blowing into the channel of an impact jet system  

Microsoft Academic Search

The authors give theoretical relations for the coefficients of hydraulic drag of jet and channel flows and a semiempirical method of calculating local heat transfer on the wall of a planar channel with blowing by a system of impact jets.

E. P. Dyban; A. I. Mazur

1987-01-01

95

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

96

Stochastic heat equation driven by fractional noise and local time  

Microsoft Academic Search

The aim of this paper is to study the d-dimensional stochastic heat equation with a multiplicative Gaussian noise which is white in space and has the covariance\\u000a of a fractional Brownian motion with Hurst parameter H ? (0,1) in time. Two types of equations are considered. First we consider the equation in the Itô-Skorohod sense, and later\\u000a in the Stratonovich

Yaozhong Hu; David Nualart

2009-01-01

97

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

98

Local thermal equilibrium for transient heat conduction: theory and comparison with numerical experiments  

Microsoft Academic Search

Local thermal equilibrium refers to the state in which a single temperature can be used to describe a heat transfer process in a multiphase system. When this condition occurs, a one-equation model can be used and the analysis of the heat transfer process is greatly simplified. In this paper we first develop the constraints that must be satisfied in order

Stephen Whitaker

1995-01-01

99

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

100

Intelligent Control of Micro Heat Exchanger with Locally Linear Identifier and Emotional Based Controller  

Microsoft Academic Search

\\u000a In this paper, an intelligent controller is applied to electrically heated micro heat exchanger. First, the dynamics of the\\u000a micro heat exchanger, which is a highly nonlinear plant, is identified using Locally Linear Model Tree (LOLIMOT) algorithm.\\u000a Then, an intelligent controller is applied to the identified model. The performance of the proposed intelligent controller\\u000a is compared with that of classic

Mahdi Jalili-kharaajoo

2005-01-01

101

Non-local gravitational effective action and particle production  

E-print Network

We study the effective action for gravity obtained after the integration of scalar matter fields, using the local momentum representation based on the Riemann normal coordinates expansion. By considering this expansion around different space-time points, we also compute the non-local terms together with the more usual divergent ones. We discuss the applicability of our results to the calculation of particle production rates in cosmological backgrounds and compare this method with the traditional Bogolyubov transformations.

A. Dobado; A. L. Maroto

1998-05-26

102

Ohmic heated sheet for the Ca ion beam production  

SciTech Connect

The production of intense accelerated {sup 48}Ca ion beams is the key problem in the experiments on the synthesis of new superheavy nuclei. For this purpose in the FLNR (JINR), an electron cyclotron resonance ion source is used at the U-400 cyclotron. The combination of a micro oven with a hot tantalum sheet inside the discharge chamber allowed the production of the intense {sup 48}Ca{sup 5+} ion beam at the {sup 48}Ca consumption of about 0.5 mg/h. In this case, the tantalum sheet is heated by microwaves and plasma electrons. The microwave power of up to 500 W is required to heat the sheet to the temperature of about 500 deg. C. To decrease the required microwave power, a new sheet with a direct Ohmic heating was designed. The present paper describes the method, technique, and preliminary experimental results on the production of the Ca ion beam.

Efremov, A.; Bogomolov, S.; Kazarinov, N.; Kochagov, O.; Loginov, V. [Joint Institute for Nuclear Research, Dubna, Moscow 141980 (Russian Federation)

2008-02-15

103

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

NASA Astrophysics Data System (ADS)

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.; Hayashi, M.; Watanabe, T.; Nagata, K.

2014-10-01

104

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

2014-10-24

105

Changing Governance of Local Economies: Responses of European Local Production Systems  

Microsoft Academic Search

This book examines patterns of economic governance in three specific, contrasting, contexts: machinery-producing districts; declining steel cities; and clusters of high-technology activities. Building on the work of their previous book (Local Production Systems in Europe: Rise or Demise? OUP 2001), which charted the recent development of local clusters of specialized manufacturing among small and medium-sized enterprises (SMEs) in France, Germany,

Colin Crouch; Patrick Le Gales; Carlo Trigilia; Helmut Voelzkow

106

Study of the change of electron temperature inside magnetic island caused by localized radio frequency heating  

SciTech Connect

The change in the electron temperature inside magnetic island caused by localized radio frequency (rf) heating is studied numerically by solving the two-dimensional energy transport equation, to investigate the dependence of the temperature change on the location and width of the rf power deposition along the minor radius and the helical angle, the island width, and the ratio between the parallel and the perpendicular heat conductivity. Based on obtained numerical results, suggestions for optimizing the island stabilization by localized rf heating are made.

Yang, J.; Zhu, S. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Center for Magnetic Fusion Theory, Chinese Academy of Sciences, Hefei 230031 (China); Yu, Q. [Max-Planck-Institute fuer Plasmaphysik, EURATOM Association, Garching 85748 (Germany); Zhuang, G. [College of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China)

2010-05-15

107

LOCAL THEORY IN CRITICAL SPACES FOR COMPRESSIBLE VISCOUS AND HEAT-CONDUCTIVE GASES  

Microsoft Academic Search

We are concerned with local existence and uniqueness of solutions for a general model of viscous and heat-conductive gases with low regularity assumptions on the initial data (the velocity and the temperature may be discontinuous). Local well-posedness is showed to hold in spaces which are critical with respect to the scaling of the equations, provided that the initial density is

Raphaël Danchin

2001-01-01

108

Local Measurement of NonClassical Ion Heating During Magnetic Reconnection  

E-print Network

Local Measurement of Non­Classical Ion Heating During Magnetic Reconnection S. C. Hsu, G. Fiksel, Princeton, NJ 08543 (November 11, 1999) Abstract Local ion temperature is measured directly in the well­characterized re­ connection layer of a laboratory plasma. These measurements demonstrate definitively that ions

109

Local Measurement of Non-Classical Ion Heating During Magnetic Reconnection  

E-print Network

Local Measurement of Non-Classical Ion Heating During Magnetic Reconnection S. C. Hsu, G. Fiksel, T, Princeton, NJ 08543 (November 11, 1999) Abstract Local ion temperature is measured directly in the well-characterized re- connection layer of a laboratory plasma. These measurements demonstrate definitively that ions

110

Local Heat Transfer and CHF for Subcooled Flow Boiling - Annual Report 1994  

SciTech Connect

The physical phenomenon of forced convective boiling is probably one of the most interesting and complex transport phenomena. It has been under study for more than two centuries. Simply stated, forced convective subcooled boiling involves a locally boiling fluid: (1) whose mean temperature is below its saturation temperature, and (2) that flows over a surface exposed uniformly or non-uniformly to a high heat flux (HHF). The objective of this work is to assess and/or improve the present ability to predict local axial heat transfer distributions in the subcooled flow boiling regime for the case of uniformly heated coolant channels. This requires an accurate and complete representation of the boiling curve up to the CHF. The present. results will be useful for both heat transfer research and industrial design applications. Future refinements may result in the application of the results to non-uniformly heated channels or other geometries, and other fluids. Several existing heat transfer models for uniformly heated channels were examined for: (1) accurate representation of the boiling curve, and (2) characterizing the local heat transfer coefficient under high heat flux (HHF) conditions. Comparisons with HHF data showed that major correlation modifications were needed in the subcooled partial nucleate boiling (SPNB) region. Since the slope of boiling curve in this region is important to assure continuity of the HHF trends into the fully developed boiling region and up to the critical heat flux, accurate characterization in the SPNB region is essential. Approximations for the asymptotic limits for the SPNB region have been obtained and have been used to develop an improved composite correlation. The developed correlation has been compared with 363 water data points. For the local heat transfer coefficient and wall temperature, the over-all percent standard deviations with respect to the data were 19% and 3%, respectively, for the high velocity water data.

Dr. Ronald D. Boyd

2000-07-01

111

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

112

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

2013-05-16

113

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

114

Green Production of CFRP Parts by Application of Inductive Heating  

Microsoft Academic Search

\\u000a Long process times, high energy consumption, low automation level and high costs for textiles, resin and production tools\\u000a are the main reasons for the low acceptance of fiber-reinforced plastics (frp) in high-volume production, especially in automotive\\u000a applications. This paper presents the potential of the application of inductive heating techniques for the reduction of process\\u000a time and energy consumption in different

Michael Frauenhofer; Stefan Kreling; Holger Kunz; Klaus Dilger

115

Conservation of Heat Energy at Hot Petroleum Products Terminals  

E-print Network

CONSERVATION OF HEAT ENERGY AT HOT PETROLEUM PRODUCTS TERMINALS J. C. Powell and R. M. Graham Exxon Company, U.S.A. Houston, Texas ABSTRACT Exxon operates several terminals which store asphalt and heavy fuel oil. Due to the rising cost... petroleum products. SCOPE OF THE STUDY The scope of the study assignment was to be fairly far reaching and included the following: 1. Identify the most energy-efficient technology available and compare it to the technology presently in use. 2. Develop...

Powell, J. C.; Graham, R. M.

1981-01-01

116

Tissue localization of maize acetylcholinesterase associated with heat tolerance in plants.  

PubMed

Our recent study reported that maize acetylcholinesterase (AChE) activity in the coleoptile node is enhanced through a post-translational modification response to heat stress and transgenic plants overexpressing maize AChE gene had an elevated heat tolerance, which strongly suggests that maize AChE plays a positive, important role in maize heat tolerance. Here we present (1) maize AChE activity in the mesocotyl also enhances during heat stress and (2) maize AChE mainly localizes in vascular bundles including endodermis and epidermis in coleoptile nodes and mesocotyls of maize seedlings. PMID:22476469

Yamamoto, Kosuke; Momonoki, Yoshie S

2012-03-01

117

Industrial restructuring as class restructuring: Production decentralization and local uniqueness  

Microsoft Academic Search

Massey D. (1983) Industrial restructuring as class restructuring: production decentralization and local uniqueness, Reg. Studies17, 73–89. Industrial change is also a process of social change. This article examines the impact on two very different kinds of area of the entry of new forms of economic activity. It points out that, although in each case the new industry was the same

Doreen Massey

1983-01-01

118

Production of high-energy chemicals using solar energy heat  

Microsoft Academic Search

Techno-economic studies and thermodynamic assessments of chemical reactions and processes were made and the market potentials for major chemical commodities that use significant amounts of fossil resources were determined in order to identify energy-intensive processes that would be suitable for the production of chemicals and fuels using solar energy process heat. Of particular importance was the comparison of relative costs

J. R. Dafler; J. Sinnott; M. Novil; B. D. Yudow; M. G. Rackoff

1978-01-01

119

A Mechanism to Explain the Exponential Model for Heat Production  

Microsoft Academic Search

Evidence for chemical interaction between plutons and meteoric ground water and analyses of the micro-scale and mega-scale distribution of uranium and thorium suggests that thermal convection in batholith complexes mobilizes uranium and may partially explain the exponential model for the vertical distribution of crustal heat production. Investigations of the distribution of uranium, thorium, and potassium within and around eight shallow

W. Gosnold

2007-01-01

120

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

121

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

122

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

123

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

NASA Astrophysics Data System (ADS)

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.

Li, Xiantao

2014-09-01

124

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

125

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

126

The local heat transfer mathematical model between vibrated fluidized beds and horizontal tubes  

SciTech Connect

A dimensionless mathematical model is proposed to predict the local heat transfer coefficients between vibrated fluidized beds and immersed horizontal tubes, and the effects of the thickness of gas film and the contact time of particle packets are well considered. Experiments using the glass beads (the average diameter bar d{sub p}=1.83mm) were conducted in a two-dimensional vibrated fluidized bed (240 mm x 80 mm). The local heat transfer law between vibrated fluidized bed and horizontal tube surface has been investigated. The results show that the values of theoretical prediction are in good agreement with experimental data, so the model is able to predict the local heat transfer coefficients between vibrated fluidized beds and immersed horizontal tubes reasonably well, and the error is in range of {+-}15%. The results can provide references for future designing and researching on the vibrated fluidized beds with immersed horizontal tubes. (author)

Zhu, Xuejun [School of Chemical Engineering, Sichuan University, Chengdu 610065 (China); College of Biology and Chemical Engineering, Panzhihua University, Panzhihua 617000 (China); Ye, Shichao; Pan, Xiaoheng [School of Chemical Engineering, Sichuan University, Chengdu 610065 (China)

2008-05-15

127

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

128

Local heat transfer distribution on a smooth flat plate impinged by a slot jet  

Microsoft Academic Search

Experimental investigation of local heat transfer distribution on a smooth flat plate impinged by a normal slot jet is conducted. Present study concentrates on the influence of jet-to-plate spacing (z\\/b) and Reynolds number on the fluid flow and heat transfer distribution. A single slot jet with an aspect ratio (l\\/b) of about 50 is chosen to get the fully developed

M. Nirmalkumar; Vadiraj Katti; S. V. Prabhu

2011-01-01

129

Local Joule heating and overall resistance increase in void-containing aluminum interconnects  

Microsoft Academic Search

Local Joule heating and the overall resistance change due to void formation in aluminum interconnects were studied numerically.\\u000a In the model the TiN\\/Al\\/TiN metallization stack is embedded within the SiO2 dielectric. Three-dimensional finite element analyses, taking into account the current shunting into the barrier layer and\\u000a the coupling between heat conduction and electrical conduction, were carried out. The temperature field

Y.-L. SHEN

2001-01-01

130

Local Joule heating and overall resistance increase in void-containing aluminum interconnects  

Microsoft Academic Search

Local Joule heating and the overall resistance change due to void formation in aluminum interconnects were studied numerically. In the model the TiN\\/Al\\/TiN metallization stack is embedded within the SiO2 dielectric. Three-dimensional finite element analyses, taking into account the current shunting into the barrier layer and the coupling between heat conduction and electrical conduction, were carried out. The temperature field

Y. L. Shen

2001-01-01

131

The bounds of the heat production rate within the moon  

NASA Technical Reports Server (NTRS)

A new approach is proposed to the evaluation of the lower and upper bounds of the global heat production rate within planetary interiors. The approach is based on the relationship between the internal energy change and the volume change of a planetary object. For illustration, the approach is applied to the moon. Using an average global surface heat flux of 18 erg/sq cm-sec, and assuming constancy of the lunar radius during the past 3.2 billion years. the lunar heat release within the past 3.2 billion years is estimated at (30 to 40) x 10 to the tenth erg/cu cm. This is equivalent to the present day uranium concentration of 35 to 50 ppb provided the radiogenic isotopes are of the same proportion as that given by Toksoz et al. (1978).

Hsui, A. T.

1979-01-01

132

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.

2011-11-04

133

Detailed measurements of local heat transfer coefficient and adiabatic wall temperature beneath an array of impinging jets  

Microsoft Academic Search

A transient method of measuring the local heat transfer under an array of impinging jets has been developed. The use of a temperature-sensitive coating consisting of three encapsulated thermochromic liquid crystal materials has allowed the calculation of both the local adiabatic wall temperature and the local heat transfer coefficient over the complete surface of the target plate. The influence of

K. W. Van Treuren; Z. Wang; P. T. Ireland; T. V. Jones

1994-01-01

134

Heat exposure, cardiovascular stress and work productivity in rice harvesters in India: implications for a climate change future.  

PubMed

Excessive workplace heat exposures create well-known risks of heat stroke, and it limits the workers' capacity to sustain physical activity. There is very limited evidence available on how these effects reduce work productivity, while the quantitative relationship between heat and work productivity is an essential basis for climate change impact assessments. We measured hourly heat exposure in rice fields in West Bengal and recorded perceived health problems via interviews of 124 rice harvesters. In a sub-group (n = 48) heart rate was recorded every minute in a standard work situation. Work productivity was recorded as hourly rice bundle collection output. The hourly heat levels (WBGT = Wet Bulb Globe Temperature) were 26-32°C (at air temperatures of 30-38°C), exceeding international standards. Most workers reported exhaustion and pain during work on hot days. Heart rate recovered quickly at low heat, but more slowly at high heat, indicating cardiovascular strain. The hourly number of rice bundles collected was significantly reduced at WBGT>26°C (approximately 5% per°C of increased WBGT). We conclude that high heat exposure in agriculture caused heat strain and reduced work productivity. This reduction will be exacerbated by climate change and may undermine the local economy. PMID:23685851

Sahu, Subhashis; Sett, Moumita; Kjellstrom, Tord

2013-01-01

135

Stretching and controlled motion of single-stranded DNA in locally heated solid-state nanopores.  

PubMed

Practical applications of solid-state nanopores for DNA detection and sequencing require the electrophoretic motion of DNA through the nanopores to be precisely controlled. Controlling the motion of single-stranded DNA presents a particular challenge, in part because of the multitude of conformations that a DNA strand can adopt in a nanopore. Through continuum, coarse-grained and atomistic modeling, we demonstrate that local heating of the nanopore volume can be used to alter the electrophoretic mobility and conformation of single-stranded DNA. In the nanopore systems considered, the temperature near the nanopore is modulated via a nanometer-size heater element that can be radiatively switched on and off. The local enhancement of temperature produces considerable stretching of the DNA fragment confined within the nanopore. Such stretching is reversible, so that the conformation of DNA can be toggled between compact (local heating is off) and extended (local heating is on) states. The effective thermophoretic force acting on single-stranded DNA in the vicinity of the nanopore is found to be sufficiently large (4-8 pN) to affect such changes in the DNA conformation. The local heating of the nanopore volume is observed to promote single-file translocation of DNA strands at transmembrane biases as low as 10 mV, which opens new avenues for using solid-state nanopores for detection and sequencing of DNA. PMID:23876013

Belkin, Maxim; Maffeo, Christopher; Wells, David B; Aksimentiev, Aleksei

2013-08-27

136

Localized Heating on Silicon Field Effect Transistors: Device Fabrication and Temperature Measurements in Fluid  

PubMed Central

We demonstrate electrically addressable localized heating in fluid at the dielectric surface of silicon-on-insulator field-effect transistors via radio-frequency Joule heating of mobile ions in the Debye layer. Measurement of fluid temperatures in close vicinity to surfaces poses a challenge due to the localized nature of the temperature profile. To address this, we developed a localized thermometry technique based on the fluorescence decay rate of covalently attached fluorophores to extract the temperature within 2 nm of any oxide surface. We demonstrate precise spatial control of voltage dependent temperature profiles on the transistor surfaces. Our results introduce a new dimension to present sensing systems by enabling dual purpose silicon transistor-heaters that serve both as field effect sensors as well as temperature controllers that could perform localized bio-chemical reactions in Lab on Chip applications. PMID:19967115

Elibol, Oguz H.; Reddy, Bobby; Nair, Pradeep R.; Dorvel, Brian; Butler, Felice; Ahsan, Zahab; Bergstrom, Donald E.; Alam, Muhammad A.; Bashir, Rashid

2010-01-01

137

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

138

Cold End Inserts for Process Gas Waste Heat Boilers Air Products, operates hydrogen production plants, which utilize large waste heat boilers (WHB)  

E-print Network

Cold End Inserts for Process Gas Waste Heat Boilers Overview Air Products, operates hydrogen production plants, which utilize large waste heat boilers (WHB) to cool process syngas. The gas enters satisfies all 3 design criteria. · Correlations relating our experimental results to a waste heat boiler

Demirel, Melik C.

139

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

140

Immunoelectron microscope localization of Mr 90000 heat shock protein and Mr 70000 heat shock cognate protein in the salivary glands of Chironomus thummi  

Microsoft Academic Search

The Mr 90000 heat shock protein (hsp 90) and one of the Mr 70000 heat shock cognate proteins (hsc 70) were localized by immunoelectron microscopy in salavary gland cells of normal and heat-shocked larvae of Chironomus thummi using polyclonal antibodies raised against Drosophila proteins. Immunoblotting after separation of proteins by gel electrophoresis shows that these antibodies cross-react with the corresponding

G. H. Vázquez-Nin; O. M. Echeverría; M. E. Carbajal; R. M. Tanguay; J. L. Diez; S. Fakan

1992-01-01

141

Identification and localization of the FMR-1 protein product  

SciTech Connect

The fragile X syndrome results from amplification of the CGG repeat found in the FMR-1 gene. As a first step in the identification and localization of the FMR-1 gene product, antibodies were raised against different regions of the FMR-1 protein (FMRP). These antibodies were used to analyze FMRP in lymphoblastoid cell lines from patients (n=5) and controls (n=3). FMRP was immunoprecipated and subsequently analyzed by immunoblotting. Four molecular species (67-74 kDa) were found which were absent in 4 of the 5 patients. The lack is in agreement with the absence of FMR-1 mRNA. The patient expressing FMRP`s shows a mosaic DNA pattern with part of the cells carrying a premutation and others carrying a full mutation. The premutation allele is preceded by an unmethylated CpG island and is expressed into FMR-1 mRNA which is subsequently translated into protein. The four different FMRPs most likely result from alternative splicing of the FMR-1 mRNA. Two splice products were mimicked in cDNA constructs transiently expressed in COS-1 cells. Both splice products appeared to encode for stable protein products and were recognized by the antibodies. The molecular weight of the protein products was in agreement with two of the protein products found in the lymphoblastoid cell lines, indicating that the FMRPs detected in lymphoblasts are the result of alternative splicing. The intracellular localization of FMRP in COS-1 cells was cytoplasmatic. The finding of four FMRPs of the same molecular weight in controls and the mosaic patient indicate that the CGG repeat is not translated.

Verheij, C.; Hoogeveen, A.T.; Verkerk, A.J.M.H.; DeGraaf, E.; Bakker, C.; Reuser, A.J.J. [Erasmus Univ., Rotterdam (Netherlands)

1994-07-15

142

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

143

Structure of the Martensite-Austenite Transition Zone After a Local Pulse Heating of the Martensite  

NASA Astrophysics Data System (ADS)

Using electron microscopy, the structure of the transition region between austenite and martensite in an austenitic-martensitic iron-chromium-nickel alloy is investigated following a local pulse heating of the martensite. It is found out that the martensite-austenite transition area has a complex structure consisting of a few regions with different phase compositions and degree of defect structure relaxation.

Blinova, E. N.; Glezer, A. M.; Libman, M. A.; Estrin, E. I.

2014-08-01

144

Low-power near-field microwave applicator for localized heating of soft matter  

Microsoft Academic Search

We report a 9 GHz near-field microwave probe for local surface heating of microwave absorbing materials. The probe radiates microwave energy through a narrow slot microfabricated at the apex of the dielectric resonator. The microwave energy is concentrated in a small region close to the applicator, in such a way that the microwave intensity there is very high. A temperature

A. Copty; F. Sakran; M. Golosovsky; D. Davidov; A. Frenkel

2004-01-01

145

Local heat flux and energy loss in a 2D vibrated granular gas  

E-print Network

We performed event-driven simulations of a two-dimensional granular gas between two vibrating walls and directly measured the local heat flux and energy dissipation rate in the stationary state. Describing the local heat flux as a function of the coordinate x in the direction perpendicular to the driving walls, we use a generalization of Fourier's law, q_x(x) = kappa d_x T(x) + mu d_x rho(x), to relate the local heat flux to the local gradients of the temperature and density. This ansatz accounts for the fact that density gradients also generate heat flux, not only temperature gradients. The transport coefficients kappa and mu are assumed to be independent of x, and we check the validity of this assumption in the simulations. Both kappa and mu are determined for different system parameters, in particular, for a wide range of coefficients of restitution. We also compare our numerical results to existing hydrodynamic theories. Agreement is found for kappa for very small inelasticities only. Beyond this region, kappa and mu exhibit a striking non-monotonic behavior.

Olaf Herbst; Peter Müller; Annette Zippelius

2004-12-13

146

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

147

Chatanika Radar Observations Relating to the Latitudinal and Local Time Variations of Joule Heating  

Microsoft Academic Search

Observations of plasma convection the complexity of the true situation and may pos- made with the Chatanika incoherent scatter radar sibly give misleading results. have been analyzed to give latitude\\/local time In a previous paper (Banks, 1977) experimental plots of the electric field contribution (E 2) to results pertaining to Joule and energetic parti- thermospheric Joule heating. The data, which

P. M. Banks; J. C. Foster; J. R. Doupnik

1981-01-01

148

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

149

Local endwall heat/mass-transfer distributions in pin fin channels  

NASA Astrophysics Data System (ADS)

Naphthalene sublimination experiments were conducted to study the effects of the pin configuration, the pin length-to-diameter ratio, and the entrance length on local endwall heat/mass transfer in a channel with short pin fins (pin length-to-diameter ratios of 0.5 and 1.0). The detailed distributions of the local endwall heat/mass-transfer coefficient were obtained for staggered and aligned arrays of pin fins, for the spanwise pin spacing-to-diameter ratio of 2.5, and for streamwise pin spacing-to-diameter ratios of 1.25 and 2.5. The Reynolds numbers were kept at about 33,000. Overall- and row-averaged Nusselt numbers compared very well with those from previous heat-transfer studies.

Lau, S. C.; Kim, Y. S.; Han, J. C.

1987-10-01

150

Current localization, non-uniform heating, and failures of ZnO varistors  

SciTech Connect

Metal oxide varistors have highly nonlinear electrical characteristics and are widely used as devices for over-voltage protection. Varistor applications range from the use of small varistors to protect delicate electronic components to the use of much larger varistors for the protection of electrical-power-distribution systems. Non-uniform heating of ZnO varistors by electrical pulses occurs on three different spatial scales: (1) microscopic (sub-micron), (2) intermediate (sub-millimeter), and (3) macroscopic (of order of millimeters or centimeters). Heating on these scales has different origins and different consequences for device failure in large and small varistors. On the microscopic scale, the heating localizes in strings of tiny hot spots. They occur at the grain boundaries in a conducting path where the potential is dropped across Schottky-type barriers. These observations are interpreted by applying transport theory and using computer simulations. It is shown that the heat transfer on a scale of the grain size is too fast to permit temperature differences that could cause a varistor failure. On an intermediate size scale, the heating is most intense along localized electrical paths. The high electrical conductivity of these paths has microstructural origin, i.e., it derives from the statistical fluctuations of grain sizes and grain boundary properties. Current localization on the intermediate size scale appears to be significant only in small varistors. On the macroscopic scale, current localization in large blocks can be attributed to inhomogeneities in the electrical properties which originate during ceramic processing. The resulting non-uniform heating is shown to cause destructive failures of large varistor blocks.

Bartkowiak, M. [Univ. of Tennessee, Knoxville, TN (United States). Dept. of Physics and Astronomy]|[Oak Ridge National Lab., TN (United States). Solid State Div.

1997-11-01

151

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

152

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

153

Nonequilibrium fluctuation-dissipation theorem and heat production.  

PubMed

We use a relationship between response and correlation function in nonequilibrium systems to establish a connection between the heat production and the deviations from the equilibrium fluctuation-dissipation theorem. This scheme extends the Harada-Sasa formulation [Phys. Rev. Lett. 95, 130602 (2005)], obtained for Langevin equations in steady states, as it also holds for transient regimes and for discrete jump processes involving small entropic changes. Moreover, a general formulation includes two times and the new concepts of two-time work, kinetic energy, and of a two-time heat exchange that can be related to a nonequilibrium “effective temperature.” Numerical simulations of a chain of anharmonic oscillators and of a model for a molecular motor driven by adenosine triphosphate hydrolysis illustrate these points. PMID:24765939

Lippiello, E; Baiesi, M; Sarracino, A

2014-04-11

154

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

155

Nonequilibrium Fluctuation-Dissipation Theorem and Heat Production  

NASA Astrophysics Data System (ADS)

We use a relationship between response and correlation function in nonequilibrium systems to establish a connection between the heat production and the deviations from the equilibrium fluctuation-dissipation theorem. This scheme extends the Harada-Sasa formulation [Phys. Rev. Lett. 95, 130602 (2005)], obtained for Langevin equations in steady states, as it also holds for transient regimes and for discrete jump processes involving small entropic changes. Moreover, a general formulation includes two times and the new concepts of two-time work, kinetic energy, and of a two-time heat exchange that can be related to a nonequilibrium "effective temperature." Numerical simulations of a chain of anharmonic oscillators and of a model for a molecular motor driven by adenosine triphosphate hydrolysis illustrate these points.

Lippiello, E.; Baiesi, M.; Sarracino, A.

2014-04-01

156

Understanding entanglement as resource: locally distinguishing unextendible product bases  

E-print Network

It is known that the states in an unextendible product basis (UPB) cannot be distinguished perfectly when the parties are restricted to local operations and classical communication (LOCC). Previous discussions of such bases have left open the following question: What entanglement resources are necessary and/or sufficient for this task to be possible with LOCC? In this paper, I present protocols which use entanglement more efficiently than teleportation to distinguish certain classes of UPB's. The ideas underlying my approach to this problem offer rather general insight into why entanglement is useful for such tasks.

Scott M. Cohen

2007-08-17

157

NONINVASIVE MEASUREMENT OF LOCAL THERMAL DIFFUSIVITY USING BACKSCATTERED ULTRASOUND AND FOCUSED ULTRASOUND HEATING  

PubMed Central

Previously, noninvasive methods of estimating local tissue thermal and acoustic properties using backscattered ultrasound have been proposed in the literature. In this article, a noninvasive method of estimating local thermal diffusivity in situ during focused ultrasound heating using beamformed acoustic backscatter data and applying novel signal processing techniques is developed. A high intensity focused ultrasound (HIFU) transducer operating at subablative intensities is employed to create a brief local temperature rise of no more than 10°C. Beamformed radio-frequency (RF) data are collected during heating and cooling using a clinical ultrasound scanner. Measurements of the time-varying “acoustic strain”, that is, spatiotemporal variations in the RF echo shifts induced by the temperature related sound speed changes, are related to a solution of the heat transfer equation to estimate the thermal diffusivity in the heated zone. Numerical simulations and experiments performed in vitro in tissue mimicking phantoms and excised turkey breast muscle tissue demonstrate agreement between the ultrasound derived thermal diffusivity estimates and independent estimates made by a traditional hot-wire technique. The new noninvasive ultrasonic method has potential applications in thermal therapy planning and monitoring, physiological monitoring and as a means of noninvasive tissue characterization. PMID:18450361

Anand, Ajay; Kaczkowski, Peter J.

2009-01-01

158

Oil production response to in situ electrical resistance heating  

E-print Network

Fleet (Member) . D. Von Gonten ( ad of Department) May 1987 ABSTRACT Oil Production Response to In Situ Electrical Resistance Heating (ERH). (May 1987) Fred William McDougal, B. S. , Texas A&M University Chair of Advisory Committee: Dr. R. A... to my father, Fred H. McDougal, whose encouragement and support culminated in the completion of my Master's work here at Texas ASM University. ACKNOWLEDGMENTS I would like to thank my wife, Carla, for her endless support and Dr. R. A. Wattenbarger...

McDougal, Fred William

2012-06-07

159

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

160

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 the global measurements of heat transport in turbulent convection [1,10­15]. An important finding thermal con- vection. A large number of global heat transport measure- ments have been carried out

Tong, Penger

161

Modulation of the axon-reflex response to local heat by reactive oxygen species in subjects with chronic fatigue syndrome.  

PubMed

Local cutaneous heating causes vasodilation as an initial first peak, a nadir, and increase to plateau. Reactive oxygen species (ROS) modulate the heat plateau in healthy controls. The initial peak, due to C-fiber nociceptor-mediated axon reflexes, is blunted with local anesthetics and may serve as a surrogate for the cutaneous response to peripheral heat. Chronic fatigue syndrome (CFS) subjects report increased perception of pain. To determine the role of ROS in this neurally mediated response, we evaluated changes in cutaneous blood flow from local heat in nine CFS subjects (16-22 yr) compared with eight healthy controls (18-26 yr). We heated skin to 42°C and measured local blood flow as a percentage of maximum cutaneous vascular conductance (%CVC(max)). Although CFS subjects had significantly lower baseline flow [8.75 ± 0.56 vs. 12.27 ± 1.07 (%CVC(max), CFS vs. control)], there were no differences between groups to local heat. We then remeasured this with apocynin to inhibit NADPH oxidase, allopurinol to inhibit xanthine oxidase, tempol to inhibit superoxide, and ebselen to reduce H(2)O(2). Apocynin significantly increased baseline blood flow (before heat, 14.91 ± 2.21 vs. 8.75 ± 1.66) and the first heat peak (69.33 ± 3.36 vs. 59.75 ± 2.75). Allopurinol and ebselen only enhanced the first heat peaks (71.55 ± 2.48 vs. 61.72 ± 2.01 and 76.55 ± 5.21 vs. 58.56 ± 3.66, respectively). Tempol had no effect on local heating. None of these agents changed the response to local heat in control subjects. Thus the response to heat may be altered by local levels of ROS, particularly H(2)O(2) in CFS subjects, and may be related to their hyperesthesia/hyperalgesia. PMID:23139367

Medow, Marvin S; Aggarwal, Arun; Baugham, Ila; Messer, Zachary; Stewart, Julian M

2013-01-01

162

Consumers' Perception of Sustainably Produced Food: The case of local and organic production technologies  

Microsoft Academic Search

This paper identifies ways to improve on the current literature regarding sustainable production technologies, in this case, organic and local products. A survey method is used to examine organic and local markets in place of a single product to gain a better understanding of consumers? response to these products, their reactions to price differences of these products, and how their

Carly S. Whorton; Vincent Amanor-Boadu

2011-01-01

163

An improved local radial point interpolation method for transient heat conduction analysis  

NASA Astrophysics Data System (ADS)

The smoothing thin plate spline (STPS) interpolation using the penalty function method according to the optimization theory is presented to deal with transient heat conduction problems. The smooth conditions of the shape functions and derivatives can be satisfied so that the distortions hardly occur. Local weak forms are developed using the weighted residual method locally from the partial differential equations of the transient heat conduction. Here the Heaviside step function is used as the test function in each sub-domain to avoid the need for a domain integral. Essential boundary conditions can be implemented like the finite element method (FEM) as the shape functions possess the Kronecker delta property. The traditional two-point difference method is selected for the time discretization scheme. Three selected numerical examples are presented in this paper to demonstrate the availability and accuracy of the present approach comparing with the traditional thin plate spline (TPS) radial basis functions.

Wang, Feng; Lin, Gao; Zheng, Bao-Jing; Hu, Zhi-Qiang

2013-06-01

164

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

165

Finding the Latent Structure in Non-local Electron Heat Transport Event  

NASA Astrophysics Data System (ADS)

Latent structures in electron heat transport in stationary, magnetically confined plasma are unmasked by dynamic transport experiment in LHD. An edge perturbation induced by a trace impurity pellet (TESPEL) injection in LHD evokes a non-local transport phenomenon (large scale transport event, LSTE, such as a core electron temperature rise in response to edge cooling). The LSTEs are not peculiar to helical plasmas nor to plasmas with an impurity pellet injection, but are a very common characteristic. At the onset of the LSTE, a first-order phase transition of the electron heat transport, which is characterized by a discontinuity of the electron temperature gradient, is found to take place over a wide region (at least 6 cm wide) in the periphery of the plasma. At about the same time, over a wide region (about 10 cm wide) in the plasma core, a second-order phase transition of the electron heat transport, which is characterized by a discontinuity of the time derivative of the electron temperature gradient, appears. Both transitions involve coherent structures of a scale much larger than a typical micro-turbulent eddy size (a few mm in this case). In order to evaluate how the local heat transport properties change during an LSTE in LHD, a new transit time distribution analysis is applied to the temporal behavior of the electron temperature gradient. The analysis results show that two large-scale coherent structures in the electron heat transport exist, and are qualitatively different from each other. Recently, we found a long distance correlation of electron temperature fluctuation of the order of 30 eV, with a size corresponding to the plasma minor radius. Therefore the non-local transport phenomenon observed in LHD is evoked by the interaction of those structures via a long distance radial correlation of electron temperature fluctuations.

Tamura, Naoki

2011-11-01

166

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

167

THERMOVISCOPLASTIC RESPONSE OF HYPERSONIC LEADING EDGE STRUCTURES SUBJECTED TO INTENSE LOCAL HEATING  

Microsoft Academic Search

A hypersonic leading edge structure subjected to intense localized transient heating is modeled using the finite element method and a three-dimensional assembly of CST-DKT plate elements in the shape of a half cylinder and incorporates the large deflection uon Kármán assumptions. The thermoviscoplastic material behavior is characterized by the Bodner-Partom constitutive model. This article compares the results of a dynamic

Ted G. Byrom; David H. Allen

1994-01-01

168

Local laser heat treatment of ultra high strength steels to improve formability  

Microsoft Academic Search

Ultra high strength steels are of enormous interest especially in the automotive industry due to their potential in realising\\u000a light weight structures and improving the crash behaviour. However the poor formability of these steels limits their application\\u000a for many parts in the car body. A solution to this limitation can be a local heat treatment using a laser beam to

Reimund Neugebauer; Sören Scheffler; Reinhart Poprawe; Andreas Weisheit

2009-01-01

169

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

170

Localized electron-cyclotron heating and current drive in the TIBER-II reactor study  

SciTech Connect

A scenario is shown for launching 10 MW of 450 GHz extraordinary-mode electron-cyclotron waves into a TIBER-II equilibrium. Localized, high-efficiency current drive near but outside the q = 2 surface causes substantial reduction in the current gradients that may play a role in major disruptions and anomalous transport. The same launch geometry shows promise for heating the plasma core during startup.

Smith, G.R.; Logan, B.G.; Kritz, A.H.

1987-09-01

171

Localized electron-cyclotron heating and current drive in the TIBER-II reactor study  

SciTech Connect

A scenario is shown for launching 10 MW of 450 GHz extraordinary-mode electron-cyclotron waves into a TIBER-II equilibrium. Localized, high-efficiency current drive near but outside the q = 2 surface causes substantial reduction in the current gradients that may play a role in major disruptions and anomalous transport. The same launch geometry shows promise for heating the plasma core during startup.

Smith, G.R.; Logan, B.G.; Kritz, A.H.

1987-05-01

172

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

173

In situ imaging highlights local structural changes during heating: the case of meat.  

PubMed

Understanding and monitoring deformation and water content changes in meat during cooking is of prime importance. We show the possibilities offered by nuclear magnetic resonance imaging (MRI) for the in situ dynamic measurement of deformation fields and water content mapping during beef heating from 20 to 75 °C. MRIs were acquired during heating, and image registration was used to calculate the deformation field. The temperature distribution in the sample was simulated numerically to link structural modifications and water transfer to temperature values. During heating, proton density decreases because of a magnetic susceptibility drop with temperature and water expulsion due to muscle contraction. A positive relationship was found between local cumulative deformation and water content. This new approach makes it possible to identify the deformation field and water transfer simultaneously and to trace thermal history to build heuristic models linking these parameters. PMID:22462532

Bouhrara, Mustapha; Clerjon, Sylvie; Damez, Jean-Louis; Kondjoyan, Alain; Bonny, Jean-Marie

2012-05-01

174

Significance of adiabatic compression in local heating of the solar corona  

NASA Astrophysics Data System (ADS)

An Investigation of the relative role and contribution of adiabatic compression versus current dissipation to local heating of an X-ray bright point(BP) in the solar corona is carried out. Using a 3D numerical simulation model LINMOD3d, we studied the energy conversion processes due to Lorentz force, pressure gradient force and Ohmic dissipation that increase the thermal energy of an X-ray BP by adiabatic compression. We found the role of compressional effects is quite dominant over the direct Joule heating in changing the temperature. Flux tube volume integration along the magnetic field shows that apart from quantitative comparison, energy conversion rates, total energies and works done by Lorentz and pressure gradient force are sharing the same dynamics. The temperature enhancement follows the same pattern. This indicates that heating this bright point might not need additional sources rather than the adiabatic compression.

Javadi Dogaheh, Setareh; Buechner, Joerg; Otto, Antonius; Carlo Santos, Jean

175

Residual Stress Measurements with Laser Speckle Correlation Interferometry and Local Heat Treating  

SciTech Connect

A new experimental technique has been devised to measure residual stresses in ductile materials with a combination of laser speckle pattern interferometry and spot heating. The speckle pattern interferometer measures in-plane deformations while the heating provides for very localized stress relief. The residual stresses are determined by the amount of strain that is measured subsequent to the heating and cool-down of the region being interrogated. A simple lumped parameter model is presented to provide a description of the method. This description is followed by presentations of the results of finite element analyses and experimental results with uniaxial test specimens. Excellent agreement between the experiments and the computer analyses were obtained.

Pechersky, M.J.; Miller, R.F. [Westinghouse Savannah River Company, SC (United States); Vikram, C.S. [University of Alabama, AL (United States)

1994-01-06

176

A non-local model of fractional heat conduction in rigid bodies  

NASA Astrophysics Data System (ADS)

In recent years several applications of fractional differential calculus have been proposed in physics, chemistry as well as in engineering fields. Fractional order integrals and derivatives extend the well-known definitions of integer-order primitives and derivatives of the ordinary differential calculus to real-order operators. Engineering applications of fractional operators spread from viscoelastic models, stochastic dynamics as well as with thermoelasticity. In this latter field one of the main actractives of fractional operators is their capability to interpolate between the heat flux and its time-rate of change, that is related to the well-known second sound effect. In other recent studies a fractional, non-local thermoelastic model has been proposed as a particular case of the non-local, integral, thermoelasticity introduced at the mid of the seventies. In this study the autors aim to introduce a different non-local model of extended irreverible thermodynamics to account for second sound effect. Long-range heat flux is defined and it involves the integral part of the spatial Marchaud fractional derivatives of the temperature field whereas the second-sound effect is accounted for introducing time-derivative of the heat flux in the transport equation. It is shown that the proposed model does not suffer of the pathological problems of non-homogenoeus boundary conditions. Moreover the proposed model coalesces with the Povstenko fractional models in unbounded domains.

Borino, G.; di Paola, M.; Zingales, M.

2011-03-01

177

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

178

Tubular reabsorption and local production of urine hepcidin-25  

PubMed Central

Background Hepcidin is a central regulator of iron metabolism. Serum hepcidin levels are increased in patients with renal insufficiency, which may contribute to anemia. Urine hepcidin was found to be increased in some patients after cardiac surgery, and these patients were less likely to develop acute kidney injury. It has been suggested that urine hepcidin may protect by attenuating heme-mediated injury, but processes involved in urine hepcidin excretion are unknown. Methods To assess the role of tubular reabsorption we compared fractional excretion (FE) of hepcidin-25 with FE of ?2-microglobulin (?2m) in 30 patients with various degrees of tubular impairment due to chronic renal disease. To prove that hepcidin is reabsorbed by the tubules in a megalin-dependent manner, we measured urine hepcidin-1 in wild-type and kidney specific megalin-deficient mice. Lastly, we evaluated FE of hepcidin-25 and ?2m in 19 patients who underwent cardiopulmonary bypass surgery. Hepcidin was measured by a mass spectrometry assay (MS), whereas ?2m was measured by ELISA. Results In patients with chronic renal disease, FE of hepcidin-25 was strongly correlated with FE of ?2m (r?=?0.93, P <0.01). In megalin-deficient mice, urine hepcidin-1 was 7-fold increased compared to wild-type mice (p?local production at 12–24 hours. Conclusions Hepcidin-25 is reabsorbed by the renal tubules and increased urine hepcidin-25 levels may reflect a reduction in tubular uptake. Uncoupling of FE of hepcidin-25 and ?2m in cardiac surgery patients suggests local production. PMID:23531037

2013-01-01

179

Simplified model for determining local heat flux boundary conditions for slagging wall  

SciTech Connect

In this work, two models for calculating heat transfer through a cooled vertical wall covered with a running slag layer are investigated. The first one relies on a discretization of the velocity equation, and the second one relies on an analytical solution. The aim is to find a model that can be used for calculating local heat flux boundary conditions in computational fluid dynamics (CFD) analysis of such processes. Two different cases where molten deposits exist are investigated: the black liquor recovery boiler and the coal gasifier. The results show that a model relying on discretization of the velocity equation is more flexible in handling different temperature-viscosity relations. Nevertheless, a model relying on an analytical solution is the one fast enough for a potential use as a CFD submodel. Furthermore, the influence of simplifications to the heat balance in the model is investigated. It is found that simplification of the heat balance can be applied when the radiation heat flux is dominant in the balance. 9 refs., 7 figs., 10 tabs.

Bingzhi Li; Anders Brink; Mikko Hupa [Aabo Akademi University, Turku (Finland). Process Chemistry Centre

2009-07-15

180

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

181

Experimental investigation of the local heat transfer in a vertical gas-liquid slug unit  

NASA Astrophysics Data System (ADS)

Heat transfer mechanism in two-phase flows and particularly in vertical slug flow is of high interest both for basic hydrodynamic research and for industrial applications. Two-phase slug flow is highly complicated and only a limited number of heat transfer studies have been carried out. The flow field around a single Taylor bubble propagating in a vertical pipe can be subdivided into three distinct hydrodynamic regions: the gas bubble surrounded by a thin liquid film, a highly turbulent liquid wake in the vicinity of the bubble bottom, and the far wake region. Experimental and theoretical works were presented during the last decades investigating the hydrodynamic parameters in each region. Due to the complexity and intermittent nature of slug flow the existing data on the heat transfer in slug flow is limited to a narrow range of operational conditions. To improve the understanding of the heat transfer mechanism in slug flow a new experimental setup was constructed. A part of the vertical pipe wall was replaced by a thin metal foil heated by electrical current. An IR video camera was used to determine the temporal variation of the instantaneous temperature field along the foil at two locations: at the thermal entrance region and at the upper part of the foil where thermal boundary is thicker. The video camera was synchronized with a sensor that determined the instantaneous location of the Taylor bubble. The results of the instantaneous heat transfer measurements along the liquid film and in the wake of the Taylor bubble can be correlated with the detailed velocity measurements carried out in the same facility (Shemer et al. 2007)[1]. The effect of the local hydrodynamic parameters on the heat transfer coefficient in each region is examined.

Babin, Valery; Shemer, Lev; Barnea, Dvora

2012-03-01

182

Production of multicharged iron ions with inductively heated vapor source  

SciTech Connect

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 from 30 to 40 kHz, respectively. The evaporator is inserted into the ECR plasma from the mirror endplate along the geometrical axis of the mirror field. Argon gas is usually chosen for supporting gas, and the working pressure is about 10{sup -4}-10{sup -3} Pa. The multicharged Fe ions are extracted from the opposite side of mirror and against the evaporator, and then multicharged Fe ion beam is formed. We compare the production of multicharged iron ions by using this source with our previous methods.

Kato, Yushi; Tomida, Masashi; Kubo, Takashi; Asaji, Toyohisa; Tanaka, Kiyokatsu; Sato, Fuminobu; Iida, Toshiyuki [Department of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka Univ. 2-1 Yamada-oka, Suita-shi, Osaka 565-0871 (Japan); Department of Electronics and Informatics, Toyama Pref. Univ. 5180 Kosugikurokawa, Imizu, Toyama 939-0398 (Japan); Department of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka Univ. 2-1 Yamada-oka, Suita-shi, Osaka 565-0871 (Japan); Department of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka Univ. 2-1 Yamada-oka, Suita-shi, Osaka 565-0871 (Japan); Tateyama Machine Co., Ltd., Tateyama Kagaku Group, 30 Shimonoban, Toyama 930-1305 (Japan); Tateyama Machine Co., Ltd., Tateyama Kagaku Group, 30 Shimonoban, Toyama 930-1305 (Japan); Department of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka Univ. 2-1 Yamada-oka, Suita-shi, Osaka 565-0871 (Japan)

2006-03-15

183

Taenia taeniaeformis: immunoperoxidase localization of metacestode culture product(s) in hyperplastic gastric mucosa.  

PubMed

Rats infected with the hepatic metacestode Taenia taeniaeformis develop an extraordinary gastric hyperplasia. Indirect immunoperoxidase staining localized larval in vitro excretory secretory product specifically in the supranuclear cytoplasm of the epithelial cells lining the pits and glands in the hyperplastic gastric mucosa. The accumulation of this substance in the stomach epithelial cells may be relevant to the gastric hyperplasia induced by tapeworm infection. PMID:3082661

Rikihisa, Y; Lin, Y C; Walton, A

1986-04-01

184

A new proposal regarding the heat generated by gravity in locally accelerating frames  

E-print Network

For Rindler observers accelerating close to the horizon in local patches around a spacetime point, the matter-energy passing through the horizon increases the entropy and heat energy. Jacobson has showed that the Einstein equation can be derived from the consideration of this thermodynamic process. This, however, works only if the acceleration $a$ is much larger than the scale set by the curvature of the spacetime. It is explored here whether an extension is possible to the case with no lower bound on $a$. We show that this is possible if one assumes that in a locally accelerating frame, the matter-energy passing through null hypersurfaces could result in an increase in the heat energy and the entropy. Such a generalisation extends the thermodynamic derivation of gravity to include any non-freely falling observer. A new method of determining the temperature detected by such locally accelerating observers is also presented. By considering only the quantisation of sufficiently localised wave modes of a field, it is shown that the observer finds himself in a thermal environment.

Swastik Bhattacharya

2014-01-28

185

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

186

Numerical modeling of diffusive heat transport across magnetic islands and local stochastic field  

SciTech Connect

The heat diffusion across magnetic islands is studied numerically and compared with analytical results. For a single island, the enhanced radial heat diffusivity, {chi}{sub r}, due to the parallel transport along the field lines is increased over a region of about the island width w. The maximum enhanced heat conductivity at the rational surface is proportional to w{sup 2}({chi}{sub parallel}{chi}{sub perpendicular}){sup 1/2} for sufficiently high values of {chi}{sub parallel}/{chi}{sub perpendicular}, where {chi}{sub parallel}/{chi}{sub perpendicular} is the ratio between the parallel and the perpendicular heat diffusivity. For low ratios of {chi}{sub parallel}/{chi}{sub perpendicular}, however, the maximum value of {chi}{sub r} is proportional to w{sup 4}{chi}{sub parallel}. In a locally stochastic magnetic field, {chi}{sub r} is again proportional to w{sup 4}{chi}{sub parallel} for low {chi}{sub parallel}/{chi}{sub perpendicular}, which is in agreement with the analytical results. With increasing {chi}{sub parallel/}{chi}{sub perpendicular}, {chi}{sub r} is dominated first by the additive effect of individual islands and then by the field ergodicity.

Yu, Q. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, D-85748 Garching (Germany)

2006-06-15

187

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

188

Metabolic heat production in electrically stimulated and non-stimulated muscle  

E-print Network

found between electrically stimulated, non- stimulated, and post glycolysis treatments. This would indicate dif- ferences in theoretical metabolic heat generation, Apparent specific heat was determined using a differential scanninng ce1orimeter as a... measure of actual metabolic heat produc- tion. Some significant differences were found in the apparent specific heat of electrically stimulated vs. non-stimulated and. post glycolysis muscle samples. The theoretical amount of metabolic heat production...

Fitzwater, Roy James

2012-06-07

189

Productivity of local chickens under village management conditions.  

PubMed

The productivity of local chickens under village management conditions was studied in six villages situated in three climatic zones within Morogoro District in Tanzania. Two villages were picked in each climatic zone (warm and wet, warm and dry, cool and wet) for the study. The data were obtained by actual measurement, qualitative observations and interview of members of the households directly responsible for the care of chickens. In addition, data sheets were given to selected farmers to record the performance of their chickens. The mean flock size for the three zones was 16.2, with a range of 2 to 58. The overall mean clutch size, egg weight and hatchability were 11.8, 44.1 g and 83.6%, respectively. The overall mean chick survival rate to 10 weeks of age was 59.7%. The mean live weights for cocks and hens were 1948 g and 1348 g, respectively. The mean growth rates to the age of 10 weeks were 4.6 g/day and 5.4 g/day, while those from 10 to 14 weeks of age were 8.4 g/day and 10.2 g/day for female and male birds, respectively. The age at first lay ranged between 6 and 8 months, and the average hen had three laying cycles per year. Most of the chickens were left to scavenge during the day and were provided with simple housing at night (95.2% of the owners). Only small amounts of supplementary feeds were occasionally given and minimal health care was provided. It was concluded that the low productivity of chickens was partly due to the prevailing poor management practices, in particular the lack of proper health care, poor nutrition and housing. PMID:12379059

Mwalusanya, N A; Katule, A M; Mutayoba, S K; Mtambo, M M A; Olsen, J E; Minga, U M

2002-09-01

190

A Simple Framework for the Dynamic Response of Cirrus Clouds to Local Diabatic Radiative Heating  

NASA Astrophysics Data System (ADS)

This paper presents a simple analytical framework for the dynamic response of cirrus to a local radiative flux convergence, expressible in terms of three independent modes of cloud evolution. Horizontally narrow and tenuous clouds within a stable environment adjust to radiative heating by ascending gradually across isentropes while spreading sufficiently fast so as to keep isentropic surfaces nearly flat. More optically dense clouds experience very concentrated heating, and if they are also very broad, they develop a convecting mixed layer. Along isentropic spreading still occurs, but in the form of turbulent density currents rather than laminar flows. A third adjustment mode relates to evaporation, which erodes cloudy air as it lofts. The dominant mode is determined from two dimensionless numbers, whose predictive power is shown in comparisons with high resolution numerical cloud simulations. The power and simplicity of the approach hints that fast, sub-grid scale radiative-dynamic atmospheric interactions might be efficiently parameterized within slower, coarse-grid climate models.

Schmidt, Clinton T.; Garrett, Timothy J.

2013-05-01

191

Physics-controlled thickness of shear zones caused by viscous heating: Implications for crustal shear localization  

NASA Astrophysics Data System (ADS)

We evaluate the parameters that control the thickness of ductile shear zones that are generated by viscous heating. We employ two-dimensional thermomechanical numerical models to simulate shear zone development under compression. Results show that the shear zone thickness is essentially independent on the numerical resolution and the initial size of a weak inclusion that triggers shear localization. A simple scaling law is derived which predicts the thickness with six physical parameters: far-field stress and strain rate, thermal conductivity (both constant and temperature dependent), initial temperature, activation energy, and stress exponent. The scaling law is confirmed by numerical simulations for a wide range of parameters. For crustal deformation conditions typical temperature increase ranges between 50°C and 200°C, and the predicted thickness is between 1 km and 7 km. These thicknesses agree with natural crustal and lithospheric shear zones suggesting that shear heating is a process controlling crustal shear zone formation.

Duretz, T.; Schmalholz, S. M.; Podladchikov, Y. Y.; Yuen, D. A.

2014-07-01

192

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

NASA Astrophysics Data System (ADS)

The heat capacity of natural (Cu12-x (Fe, Zn, Ag)x(Sb, As)4S13) and synthetic (Cu12-xZnxSb4S13 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.; May, A. F.; Delaire, O.; McGuire, M. A.; Lu, X.; Liu, Cheng-Yun; Case, E. D.; Morelli, D. T.

2014-05-01

193

Low-Temperature Heat Capacity and Localized Vibrational Modes in Natural and Synthetic Tetrahedrites  

SciTech Connect

The heat capacity of natural (Cu12-x (Fe, Zn, Ag)x(Sb, As)4S13) and synthetic (Cu12-xZnxSb4S13 with x=0, 1, 2) tetrahedrite compounds was measured between 2K and 380K. 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 vibration 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, Edgar [ORNL] [ORNL; May, Andrew F [ORNL] [ORNL; Delaire, Olivier A [ORNL] [ORNL; McGuire, Michael A [ORNL] [ORNL; Lu, Xu [Michigan State University] [Michigan State University; Li, Cheng-Yun [Michigan State University] [Michigan State University; Case, Eldon D [Michigan State University, East Lansing] [Michigan State University, East Lansing; Morelli, Donold [Michigan State University, East Lansing] [Michigan State University, East Lansing

2014-01-01

194

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

195

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

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

Probing the local temperature by in situ electron microscopy on a heated Si(3)N(4) membrane.  

PubMed

We present a method allowing us to obtain localized heating that is compatible with high-temperature operation and real time scanning and transmission electron microscopy. Localized heating is induced by flowing current through tungsten nanowires deposited by focused ion-beam-induced deposition on a 50-nm-thick Si(3)N(4) membrane. Based on the heat transport between the nanowire and the substrate, we applied an analytical model to obtain the temperature profile as a function of electrical power. In this model, the key parameter is the thermal resistance between the nanowire and the substrate that we determined experimentally by measuring electrical power and local temperature. The local temperature is measured by observing the evaporation of gold nanoparticle by electron microscopy. These in situ heating and temperature-probing capabilities are used to study the crystallization of the Si(3)N(4) membrane and the growth of silicon nanowires. PMID:19828252

Reguer, A; Bedu, F; Nitsche, S; Chaudanson, D; Detailleur, B; Dallaporta, H

2009-12-01

198

Experimental analysis of the local heat transfer coefficient of falling film evaporation with and without co-current air flow velocity  

Microsoft Academic Search

This paper presents the experimental results of the local heat transfer for falling film evaporation of water sheet by solving the inverse heat conduction problem. It is shown that the local heat transfer coefficients increase by increasing the air flow velocity, the film liquid flow rate or decreasing the inlet bulk film temperature. Correlations for the mean heat transfer coefficients

H. Louahlia-Gualous; L. El. Omari; P. K. Panday; E Artioukhine

2005-01-01

199

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

200

Constructing a model of 3D radiogenic heat production in Ireland  

NASA Astrophysics Data System (ADS)

Heat production values in the crust and mantle rock inform heat flow density data to provide crucial information about the structure of the Earth's lithosphere. In addition, accurate models of horizontal and vertical distribution of heat production can help to define geothermal exploration targets. Low-enthalpy district scale space heating and Enhanced Geothermal Systems (EGS) using hot, dry rock may provide sustainable energy resources in regions currently perceived as having low geothermal energy potential. Ireland is located within stable lithosphere, unaffected by recent tectonism and volcanism, and has an estimated heat flow range below the measured global continental average. Nevertheless, borehole data indicate that heat production is variable across the island, with anomalously high rates observed, for example, in Cavan, Meath and Antrim. Data coverage is, however, poor. Radioactive isotopic decay generates heat in rock. By using established heat production constants and known concentrations of unstable isotopes of uranium, thorium and potassium, along with rock density values, a heat production rate in ?W m -3 is obtained. With the objective of compiling the first comprehensive database of information about the Irish lithosphere, in three dimensions, the authors present here initial results obtained from published and unpublished whole-rock major and trace element analyses. The presence of systematic trends correlating heat production to properties such as age and lithology are also investigated. Offering insight into the vertical component of heat production distribution, Irish xenoliths emplaced in Lower Carboniferous volcanics are regarded as a reliable proxy for the present-day lower crust. Their geochemical composition gives heat production values that are higher than expected for the depths indicated by their thermobarometric data, suggesting that heat production rates do not simply reduce with depth.

Willmot Noller, N. M.; Daly, J. S.

2012-04-01

201

Localization of heat shock proteins in cerebral cortical cultures following induction by celastrol.  

PubMed

Hsp70, Hsp32, and Hsp27 were induced by celastrol in rat cerebral cortical cultures at dosages that did not affect cell viability. Pronounced differences were observed in the cellular localization of these heat shock proteins in cell types of cerebral cortical cultures. Celastrol-induced Hsp70 localized to the cell body and cellular processes of neurons that were identified by neuron-specific ?III-tubulin. Hsp70 was not detected in adjacent GFAP-positive glial cells that demonstrated a strong signal for Hsp27 and Hsp32 in both glial cell bodies and cellular processes. Cells in the cerebral cortex region of the brain are selectively impacted during the progression of Alzheimer's disease which is a "protein misfolding disorder." Heat shock proteins provide a line of defense against misfolded, aggregation-prone proteins. Celastrol is a potential agent to counter this neurodegenerative disorder as recent evidence indicates that in vivo administration of celastrol in a transgenic model of Alzheimer's reduces an important neuropathological hallmark of this disease, namely, amyloid beta pathology that involves protein aggregation. PMID:24700193

Chow, Ari M; Tang, Derek W F; Hanif, Asad; Brown, Ian R

2014-11-01

202

Local convection heat transfer on a plane wall in the vicinity of strong streamwise accelerations  

NASA Astrophysics Data System (ADS)

In unshrouded turbine stages in gas turbine engines, a stationary outer ring or shroud is used as a noncontacting seal to contain the hot gas flow within the desired path between the turbine blades. In normal operation a clearance gap exists between the blade tips and outer ring, and the hot gases are forced through the gap by the pressure difference between the blade pressure and suction sides. High levels of acceleration exist as the flow moves into the clearance gap from the pressure side of the blade passage, and as the flow accelerates into the gap it is expected that it will act to increase heat transfer on the adjacent outer ring segment as the velocity adjacent to the surface increases. This expected increase may be offset by the tendency for the flow to laminarize under the influence of strong acceleration, even though the acceleration length in the streamwise direction is short. An experimental study was designed and performed to model accelerating flow into a gap, and the results presented indicate that even very short lengths of acceleration produce large effects on the local convection heat transfer. Both acceleration and reverse transition appear to act together to produce a characteristic nonmonotonic variation in heat transfer.

Stanewich, B. J.; Metzger, D. E.

203

Effect of surface roughness on local film cooling effectiveness and heat transfer coefficients  

NASA Astrophysics Data System (ADS)

In high temperature gas turbine engines, the life cycle of the hot section is extremely dependent on accurate design prediction of component temperature distribution. Particular attention must be paid to the film cooling performance of the first stage turbine stator vanes where the highest heat loads are encountered. Recent investigations have determined during operation the smooth surface of high pressure turbine vanes become rough due to corrosion, oxidation and particulate impact. A transient experimental method has been developed to obtain both local heat transfer and cooling effectiveness information downstream of a row of film cooling holes on a rough flat plate. This investigation provides information on the effects of roughness on film cooling heat transfer for a Reynolds number and dimensionless boundary layer momentum thickness which match conditions applicable to the pressure side of the first stage turbine vane of the Pratt and Whitney F-100-PW229 engine. Data for film cooling on rough surfaces are extremely limited in the literature. However, comparison with the available data is made.

Barlow, Douglas N.

1994-08-01

204

“A shattered visage lies”: sustainable design and local scale production  

Microsoft Academic Search

This paper discusses Ecodesign and sustainable design of products from the scientific, ethical, aesthetic and spiritual perspectives. It argues that if sustainability is to be worked towards, and if Ecodesign is to be applied to products and product manufacturing, then we must bring new considerations to the fore and include a more holistic understanding in our conceptions of products and

Stuart Walker

1999-01-01

205

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 resolution) of time period June 1 to September 30 from year 2002 to 2005 to study the heat island (HI:30 am, CST) data have been used. The existence of a heat island (HI) of the San Antonio downtown area

Texas at San Antonio, University of

206

Heat-shield for gas-burning flare in oil production installations, particularly platforms at sea  

Microsoft Academic Search

A process is disclosed to protect oil production installations from heat radiation given off by the flame of a gas-burning flare. In said process, a heat-shield is installed a short distance below the flare nozzle, to protect installations from at least part of the heat radiated by the flare flame.

G. Chaudot; R. Ombret; P. Zimmerman

1982-01-01

207

HEAT CONDUCTION AND ENTROPY PRODUCTION IN ANHARMONIC CRYSTALS WITH SELF-CONSISTENT  

E-print Network

baths with which they can exchange energy. To obtain a heat flow between external reservoirs not hold when the "noise" is turned off (the heat conductivity then becoming infinite), one expectsHEAT CONDUCTION AND ENTROPY PRODUCTION IN ANHARMONIC CRYSTALS WITH SELF-CONSISTENT STOCHASTIC

Paris-Sud XI, Université de

208

High-temperature strength of prealloyed-powder products increased by heat/pressure treatment  

NASA Technical Reports Server (NTRS)

Heat treatment process involves heating products to a temperature above the solidus, and subsequently applying pressure at a temperature below the solidus. Technique can be modified to one step process involving simultaneous application if both high pressure and heat. Process is not limited to cobalt-base alloys.

Ashbrook, R. L.; Freche, J. C.; Waters, W. J.

1971-01-01

209

608 IEEE TRANSACTIONS ON ADVANCED PACKAGING, VOL. 23, NO. 4, NOVEMBER 2000 MEMS Post-Packaging by Localized Heating and  

E-print Network

for microsystems and recommends specific research di- rections by localized heating and bonding. Micropackaging has an integrated low pressure chemical vapor deposition (LPCVD) sealing process, localized silicon-gold eutectic glass and silicon for chemical sensors. Laskar and Blythe [11] developed a multichip modules (MCM) type

Lin, Liwei

210

Reactive oxygen species (ROS) from NADPH and xanthine oxidase modulate the cutaneous local heating response in healthy humans  

PubMed Central

Local cutaneous heating produces vasodilation that is largely nitric oxide (NO) dependent. We showed that angiotensin II (ANG II) attenuates this by an ANG II receptor, type 1 (AT1R)-dependent mechanism that is reversible with the antioxidant ascorbate, indicating oxidative stress. Reactive oxygen species (ROS) produced by ANG II employ NADPH and xanthine oxidase pathways. To determine whether these mechanisms pertain to skin, we measured cutaneous local heating with 10 ?M ANG II, using apocynin to inhibit NADPH oxidase and allopurinol to inhibit xanthine oxidase. We also inhibited superoxide with tempol, and H2O2 with ebselen. We heated the skin of the calf in 8 healthy volunteers (24.5–29.9 yr old) to 42°C and measured local blood flow to assess the percentage of maximum cutaneous vascular conductance. We remeasured while perfusing allopurinol, apocynin, ebselen, and tempol through individual microdialysis catheters. This was then repeated with ANG II combined with antioxidant drugs. tempol and apocynin alone had no effect on the heat response. Allopurinol enhanced the entire response (125% of heat alone), while ebselen suppressed the heat plateau (76% of heat alone). ANG II alone caused significant attenuation of the entire heat response (52%). When added to ANG II, Allopurinol partially reversed the ANG II attenuation. Heat with ebselen and ANG II were similar to heat and ANG II; ebselen only partially reversed the ANG II attenuation. Apocynin and tempol each partially reversed the attenuation caused by ANG II. This suggests that ROS, produced by ANG II via NADPH and xanthine oxidase pathways, modulates the response of skin to the application of heat, and thus contributes to the control of local cutaneous blood flow. PMID:21436462

Bamji, Natasha; Clarke, Debbie; Ocon, Anthony J.; Stewart, Julian M.

2011-01-01

211

Methods for mapping local food production capacity from agricultural statistics  

Microsoft Academic Search

Interest in local food security has increased in the last decade, stemming from concerns surrounding environmental sustainability, small scale agriculture, and community food security. Promotions for consumption of locally produced foods have come from activists, non-governmental organizations, as well as some academic and government research and policy makers. Methods to empirically assess the types and quantities of crops and animals

Kathryn T. Morrison; Trisalyn A. Nelson; Aleck S. Ostry

2011-01-01

212

Heat transfer characteristics of radial liquid film flow (local heat transfer characteristics near the turbulent transition point)  

Microsoft Academic Search

It is well known that a circular liquid jet impinging on a flat plate has high heat transfer efficiency. Because such a high heat transfer efficiency can be achieved without sophisticated apparatus, the impinging jet is applied to heating and cooling of a wide range of industrial apparatus, such as the quenching of steel during the rolling process or, conversely,

Kenji Katoh; Tsuneo Azuma; Shinji Kano

1995-01-01

213

Local Heat and Mass Transfer in a Counter-current Slug Flow Absorber for Ammonia-water Absorption Heat Pump System  

NASA Astrophysics Data System (ADS)

This study deals with experimental results and data reduction model for a counter-current slug flow absorber working with ammonia-water mixture for significantly low solution flow rate-condition that is required for operating as the GAX cycle. From visualization results of flow pattern, frost flow just after the gas inlet followed by slug flow with well-shaped Taylor bubble are observed, while dry patch on the tube wall are not observed. The local heat flow rate is measured by varying main parameters, namely, pressure, ammonia gas flow rate, solution flow rate, ammonia concentration of inlet solution and coolant inlet conditions. A data reduction model to obtain local heat and mass transfer coefficient on the liquid side is proposed by using the drift flux model to analyze the flow characteristics. Control volume method and heat and mass transfer analogy are employed to solve the combined heat and mass transfer problem. As a result, it is found that the local heat and mass transfer coefficient on the liquid side is greatly influenced by the flow pattern. The heat and mass transfer coefficient at the frost flow region is higher than that at the slug flow region due to flow disturbance and random fluctuation.

Koyama, Shigeru; B. Saha, Bidyut; Kim, Hyun-Young

214

Influence of protein heat treatment on the continuous production of food foams  

Microsoft Academic Search

The influence of WPI heat treatment on the continuous production of food foams was investigated using a model food including xanthan. The temperature of heat treatment was increased up to 90°C using a plate heat exchanger; a rotor–stator unit was used for aeration purpose. The aim was to determine the interplay between heat-induced protein denaturation and aggregation, and the process

I. Nicorescu; C. Vial; C. Loisel; A. Riaublanc; G. Djelveh; G. Cuvelier; J. Legrand

2010-01-01

215

Engineered heat treated methanogenic granules: A promising biotechnological approach for extreme thermophilic biohydrogen production  

Microsoft Academic Search

In the present study, two granular systems were compared in terms of hydrogen production rate, stability and bacterial diversity under extreme thermophilic conditions (70°C). Two EGSB reactors were individually inoculated with heat treated methanogenic granules (HTG) and HTG amended with enrichment culture with high capacity of hydrogen production (engineered heat treated methanogenic granules – EHTG), respectively. The reactor inoculated with

Angela A. Abreu; Joana I. Alves; M. Alcina Pereira; Dimitar Karakashev; M. Madalena Alves; Irini Angelidaki

2010-01-01

216

Heating of thin products by means of transverse-flux inductors  

NASA Astrophysics Data System (ADS)

There are some forms of metallic products which do not lend themselves well to induction heating upon first consideration, either because of their shape (small thickness) or their nature (materials with low resistance). In particular, this applies to all products in the form of a thin sheet. Various applications are suggested such as the drying of the sheet after pickling the heating of the sheet in order to dry or harden varnish lacquer, and the heat treatment of aluminium sheet.

1980-02-01

217

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

218

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

219

Kondo Signature in Heat Transfer via a Local Two-State System  

NASA Astrophysics Data System (ADS)

We study the Kondo effect in heat transport via a local two-state system. This system is described by the spin-boson Hamiltonian with Ohmic dissipation, which can be mapped onto the Kondo model with anisotropic exchange coupling. We calculate thermal conductance by the Monte Carlo method based on the exact formula. Thermal conductance has a scaling form ?=(kB2TK/?)f(?,T/TK), where TK and ? indicate the Kondo temperature and dimensionless coupling strength, respectively. Temperature dependence of conductance is classified by the Kondo temperature as ??(T/TK)3 for T?TK and ??(kBT/??c)2?-1 for T?TK. Similarities to the Kondo signature in electric transport are discussed.

Saito, Keiji; Kato, Takeo

2013-11-01

220

Nanoimprinted polymer chips for light induced local heating of liquids in micro- and nanochannels  

NASA Astrophysics Data System (ADS)

A nanoimprinted polymer chip with a thin near-infrared absorber layer that enables light-induced local heating (LILH) of liquids inside micro- and nanochannels is presented. An infrared laser spot and corresponding hot-spot could be scanned across the device. Large temperature gradients yield thermophoretic forces, which are used to manipulate and stretch individual DNA molecules confined in nanochannels. The absorber layer consists of a commercially available phthalocyanine dye (Fujifilm), with a narrow absorption peak at approximately 775 nm, dissolved in SU-8 photoresist (Microchem Corp.). The 500 nm thick absorber layer is spin-coated on a transparent substrate and UV exposed. Microand nanofluidic channels are defined by nanoimprint lithography in a 1.5 ?m thick layer of low molecular weight polymethyl methacrylate (PMMA, Microchem Corp.), which is spin coated on top of the absorber layer. We have used a previously developed two-level hybrid stamp for replicating two V-shaped microchannels (width=50 ?m and height = 900 nm) bridged by an array of 200 nanochannels (width and height of 250 nm). The fluidic channels are finally sealed with a lid using PMMA to PMMA thermal bonding. Light from a 785 nm laser diode was focused from the backside of the chip to a spot diameter down to 5 ..m in the absorber layer, yielding a localized heating (Gaussian profile) and large temperature gradients in the liquid in the nanochannels. A laser power of 38 mW yielded a temperature of 40oC in the center of a 10 ?m 1/e diameter. Flourescence microscopy was performed from the frontside.

Thamdrup, Lasse H.; Pedersen, Jonas N.; Flyvbjerg, Henrik; Larsen, Niels B.; Kristensen, Anders

2010-08-01

221

Simulated and Observed Influence of the Nocturnal Urban Heat Island on the Local Wind Field.  

NASA Astrophysics Data System (ADS)

A three-dimensional primative equation model was used to simulate the low-level wind field, given the urban heat island as the lower temperature boundary condition. The specification of the average heat island bypassed the need to calculate the surface energy budget, considerably simplifying the model. This is especially desirable since temperature is a more accurate and easily obtainable measurement. The influence of the Washington, DC urban area on the local airflow was to enhance the vertical mixing due to the increased low-level instability as the air approached the warmer city center. This resulted in the lower-level winds turning anticyclonically (clockwise) from the upwind value. The anticyclonic turning, on the order of a degree per kilometer, is due to an increase in the downward transport of momentum and is accompanied by a wind speed increase of 17%. The upwind direction is quickly reestablished downwind of the city. The influence of the terrain upon the wind field could not be determined from the calculations since terrain effects were included in the surface temperature boundary condition. Observations from three instrumented towers around the perimeter of the urban center were not sufficient to deduce the complex nature of the flow. However, during southwest flow when two of the towers were downwind of the urban center, the mean wind direction between those towers was significantly different by 20°.

Draxler, Roland R.

1986-08-01

222

A comparison of the transient and heated-coating methods for the measurement of local heat transfer coefficients on a pin fin  

Microsoft Academic Search

Measurements of the local heat transfer coefficients on a pin fin (i.e., a short cylinder in crossflow) in a duct have been using two methods, both of which employ liquid crystals to map an isotherm on the surface. The transient method uses the liquid crystal to determine the transient response of the surface temperature to a change in the fluid

J. W. Baughn; N. Saniei; P. T. Ireland; T. V. Jones

1989-01-01

223

DEVELOPMENT OF LOCAL PRODUCTIVE SETTLEMENTS (CLUSTERS): PRE-PROSPECTIVE RESEARCH OF THE FOOTWEAR  

E-print Network

. Keywords: clusters; local productive settlements; small and medium enterprises; forecasting. sic_00000860DEVELOPMENT OF LOCAL PRODUCTIVE SETTLEMENTS (CLUSTERS): PRE-PROSPECTIVE RESEARCH OF THE FOOTWEAR to the international competition imposes challenges to the Brazilian small and medium enterprises, SME´s. In Brazil

Boyer, Edmond

224

The Relative Importance of Search versus Credence Product Attributes: Organic and Locally Grown  

Microsoft Academic Search

Organic foods and local foods have come to the forefront of consumer issues, due to concerns about nutrition, health, sustainability, and food safety. A conjoint analysis experiment quantified the relative importance of, and trade-offs between, apple search and experience attributes (quality\\/blemishes, size, flavor), credence attributes (conventional vs. organic production method, local origin vs. product of USA vs. imported), and purchase

Ferdinand F. Wirth; John L. Stanton; James B. Wiley

2011-01-01

225

Effect of heating system using a geothermal heat pump on the production performance and housing environment of broiler chickens.  

PubMed

A geothermal heat pump (GHP) is a potential heat source for the economic heating of broiler houses with optimum production performance. An investigation was conducted to evaluate the effect of a heating system using a GHP on production performance and housing environment of broiler chickens. A comparative analysis was also performed between the GHP system and a conventional heating system that used diesel for fuel. In total, 34,000 one-day-old straight run broiler chicks were assigned to 2 broiler houses with 5 replicates in each (3,400 birds/replicate pen) for 35 d. Oxygen(,) CO(2), and NH(3) concentrations in the broiler house, energy consumption and cost of heating, and production performance of broilers were evaluated. Results showed that the final BW gain significantly (P < 0.05) increased when chicks were reared in the GHP broiler house compared with that of chicks reared in the conventional broiler house (1.73 vs. 1.62 kg/bird). The heating system did not affect the mortality of chicks during the first 4 wk of the experimental period, but the mortality markedly increased in the conventional broiler house during the last wk of the experiment. Oxygen content in the broiler house during the experimental period was not affected by the heating system, but the CO(2) and NH(3) contents significantly increased (P < 0.05) in the conventional broiler house compared with those in the GHP house. Fuel consumption was significantly reduced (P < 0.05) and electricity consumption significantly increased (P < 0.05) in the GHP house compared with the consumption in the conventional house during the experiment. The total energy cost of heating the GHP house was significantly lower (P < 0.05) compared with that of the conventional house. It is concluded that a GHP system could increase the production performance of broiler chicks due to increased inside air quality of the broiler house. The GHP system had lower CO(2) and NH(3) emissions with lower energy cost than the conventional heating system for broiler chickens. PMID:22252338

Choi, H C; Salim, H M; Akter, N; Na, J C; Kang, H K; Kim, M J; Kim, D W; Bang, H T; Chae, H S; Suh, O S

2012-02-01

226

Suppression of local heat flux in a turbulent magnetized intracluster medium  

NASA Astrophysics Data System (ADS)

X-ray observations of hot gas in galaxy clusters often show steeper temperature gradients across cold fronts - contact discontinuities, driven by the differential gas motions. These sharp (a few kpc wide) surface brightness/temperature discontinuities would be quickly smeared out by the electron thermal conduction in unmagnetized plasma, suggesting significant suppression of the heat flow across the discontinuities. In fact, the character of the gas flow near cold fronts is favourable for suppression of conduction by aligning magnetic field lines along the discontinuities. We argue that a similar mechanism is operating in the bulk of the gas. Generic 3D random isotropic and incompressible motions increase the temperature gradients (in some places) and at the same time suppress the local conduction by aligning the magnetic field lines perpendicular to the local temperature gradient. We show that the suppression of the effective conductivity in the bulk of the gas can be linked to the increase of the frozen magnetic field energy density. On average the rate of decay of the temperature fluctuations d/dt decreases as -1/5.

Komarov, S. V.; Churazov, E. M.; Schekochihin, A. A.; ZuHone, J. A.

2014-05-01

227

A technique for locally increasing surface heat spreading and through-thickness thermal conductivity of graphite/epoxy laminates  

SciTech Connect

The polymer matrix composite through-thickness thermal conductivity is particularly important in applications such as composite space borne electronics enclosures where the heat dissipation is entirely dependent on thermal conduction to a heat sink. The spreading of heat at the composite surface and subsequent localized conduction in the through-thickness direction down to high thermal conductivity fiber may be the key to designing a lightweight, thermally efficient enclosure. A finite element model was constructed of a composite with heat applied to a central area. The laminate consisted of a hybrid of high thermal conductivity pitch fiber/epoxy (K1100/ERL 1939-3) on the outside surfaces interlaminated with low thermal conductivity carbon fabric/epoxy (HMF-322D/7714AC) in a [{+-}10{degree}, (45{degree}), {+-}10{degree}, ({ovr 45}{degree})]{sub s} configuration. Three configurations were modeled: (A) a heat source in the middle, (B) Cu plating under the central heat source and (C) Cu plating under the heat source with a centrally located hole that was also Cu plated. The model with Cu on the surface under the heat source had a maximum surface temperature 35% lower than the model with no Cu to spread the heat. The model with a central Cu plated hole had a maximum surface temperature 58% lower than that with no Cu plating on the surface. Therefore, the surface Cu plating with Cu plated hole spreads the heat and increases the through-thickness thermal conductivity.

Roberts, J.C.; Luesse, M.H.; Magee, T.C. [Johns Hopkins University, Baltimore, MD (United States)

1994-12-31

228

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

229

Local heat transfer in a system of impact jets with one-sided outlet of the flow  

Microsoft Academic Search

A new method is presented for generalizing local coefficients of heat transfer in a system of impact jets with one-sided flow outlet. The method is based on the concept of a corrective multiplier, epsilon = Nu(i)\\/free-stream Nu(i), which takes account of intensification of heat transfer at the thermal stabilization region of the channel. In this approach the surface cooled by

A. I. Mazur; E. P. Dyban; V. P. Golovanov; I. G. Davydenko

1978-01-01

230

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

231

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

232

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

233

Stretching and Controlled Motion of Single-Stranded DNA in Locally-Heated Solid-State Nanopores  

PubMed Central

Practical applications of solid-state nanopores for DNA detection and sequencing require the electrophoretic motion of DNA through the nanopores to be precisely controlled. Controlling the motion of single-stranded DNA presents a particular challenge, in part because of the multitude of conformations that a DNA strand can adopt in a nanopore. Through continuum, coarse-grained and atomistic modeling, we demonstrate that local heating of the nanopore volume can be used to alter the electrophoretic mobility and conformation of single-stranded DNA. In the nanopore systems considered, the temperature near the nanopore is modulated via a nanometer-size heater element that can be radiatively switched on and off. The local enhancement of temperature produces considerable stretching of the DNA fragment confined within the nanopore. Such stretching is reversible, so that the conformation of DNA can be toggled between compact (local heating is off) and extended (local heating is on) states. The effective thermophoretic force acting on single-stranded DNA in the vicinity of the nanopore is found to be sufficiently large (4–8 pN) to affect such changes in the DNA conformation. The local heating of the nanopore volume is observed to promote single-file translocation of DNA strands at transmembrane biases as low as 10 mV, which opens new avenues for using solid-state nanopores for detection and sequencing of DNA. PMID:23876013

Belkin, Maxim; Maffeo, Christopher; Wells, David B.

2013-01-01

234

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

235

June 8, 2012 LOCAL WINDS AND RAIN OF HAWAI'I Figure 1 Sea breeze and land breeze circulations are driven by differential heating.  

E-print Network

approaches the Hawaiian Islands, the mountains and daily heating cycle over the islands disturbs the flow Sea breeze and land breeze circulations are driven by differential heating. Title: Local Winds. Sunlight heats the land more rapidly. Heat energy is redistributed through ocean currents and atmospheric

Businger, Steven

236

Consumer-directed health insurance products: local-market perspectives.  

PubMed

During the past few years, health plans have focused product development on consumer-driven health plans. This paper examines how these products are faring in twelve Community Tracking Study (CTS) communities. Although there has been a proliferation in the number and variety of consumer-directed plan options available, employers have taken a cautious approach. Given the increased financial stake and decision-making responsibility consumers hold when enrolled in these plans, respondents expressed frustration that the availability of information support has lagged behind the demands placed on consumers. PMID:16684742

Regopoulos, Lydia; Christianson, Jon B; Claxton, Gary; Trude, Sally

2006-01-01

237

A New Facility for Measurements of Three-Dimensional, Local Subcooled Flow Boiling Heat Flux and Related Critical Heat Flux for PFCs  

SciTech Connect

In the development of plasma-facing components for fusion reactors and high-heat-flux heat sinks (or components) for electronic applications, the components are usually subjected to a peripherally nonuniform heat flux. Even if the applied heat flux is uniform in the axial direction (which is unlikely), both intuition and recent investigations have clearly shown that both the local heat flux and the eventual critical heat flux (CHF) in this three-dimensional (3-D) case will differ significantly from similar quantities found in the voluminous body of data for uniformly heated flow channels. Although this latter case has been used in the past as an estimate for the former case, more study has become necessary to examine the 3-D temperature and heat flux distributions and related CHF. Work thus far has shown that the nonuniform peripheral heat flux condition enhances CHF in some cases.To avoid the excess costs associated with using electron or ion beams to produce the nonuniform heat flux, a new facility was developed that will allow 3-D conjugate heat transfer measurements and two-dimensional, local subcooled flow boiling heat flux and related CHF measurements.The configurations under study for this work consist of (a) a nonuniformly heated cylinder-like test section with a circular coolant channel bored through the center and (b) a monoblock that is a square cross-section parallelepiped with a circular drilled flow channel along the channel centerline. The theoretical or ideal cylinder-like test section would be a circular cylinder with half (-90 to 90 deg) of its outside boundary subjected to a uniform heat flux and the remaining half insulated. For the monoblock, a uniform heat flux is applied to one of the outside surfaces, and the remaining surfaces are insulated. The outside diameter of the cylinder-like test section is 30.0 mm, and its length is 200.0 mm. The monoblock square is 30.0 mm long. The inside diameter of the flow channel for both types of test sections is 10.0 mm. Water is the coolant. The inlet water temperature can be set at any level in the range from 26.0 to 130.0 deg. C, and the exit pressure can be set at any level in the range from 0.4 to 4.0 MPa. Thermocouples were placed at 48 locations inside the solid cylinder-like or monoblock test section to obtain 3-D wall temperature variations and related local heat flux. Finally, the mass velocity can be set at any level in the range from 0.4 to 10.0 Mg/m{sup 2}.s for the 10.0-mm-diam channel.

Boyd, Ronald D. Sr.; Cofie, Penrose; Li Qingyuan; Ekhlassi, Ali A

2002-01-15

238

Numerical modeling of compact high temperature heat exchanger and chemical decomposer for hydrogen production  

Microsoft Academic Search

The present study addresses fluid flow and heat transfer in a high temperature compact heat exchanger which will be used as\\u000a a chemical decomposer in a hydrogen production plant. The heat exchanger is manufactured using fused ceramic layers that allow\\u000a creation of channels with dimensions below 1 mm. The main purpose of this study is to increase the thermal performance of

Valery Ponyavin; Yitung Chen; Anthony E. Hechanova; Merrill Wilson

2008-01-01

239

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

240

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 underlines the spatial transition of energy production relating to the spreading of wind turbines Europe. From a rural perspective, the spreading of wind energy parks is the comeback of energy production

Boyer, Edmond

241

Influence of Product Yield, Density, Heating Conditions and Conversion on Pyrolysis of Biomass  

Microsoft Academic Search

Biomass is an attractive option as a fuel for power generation. The pyrolysis process consists of the thermal degradation of biomass feedstock in the absence of oxygen\\/air. In the present study, the simultaneous chemical kinetics and heat transfer model is used to predict the effects of heating conditions, density of biomass, product yields and conversion on pyrolysis of biomass fuels.

A. S. CHAURASIA; B. V. BABU

242

Preliminary study of a radiantly heated bed for the production of high-purity silicon  

Microsoft Academic Search

This article describes the exploration of a processing method which uses radiant heating of the particles of a fluidized bed for the production of high-purity silicon. The process involves heating the particles at the surface of a shallow fluidized bed by radiant heaters located above the surface of the bed. The radiant sources could be cooled by a purge of

O. Levenspiel; M. B. Larson; F. Ouyang; G. T. Zhang

1984-01-01

243

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

244

Radiogenic heat production in the Variscan crust: new determinations and distribution models in Corsica (northwestern Mediterranean)  

NASA Astrophysics Data System (ADS)

New heat-production values of Variscan volcanic rocks cropping out in the southern part of the Corsican batholith were determined in the laboratory by analysing uranium, thorium and potassium concentrations with gamma-ray spectrometry. They vary from a minimum of 0.2 for basalts to a maximum of 4.2 ?W m -3 for calc-alkaline granites. The Th/U ratio in Variscan granitoids is slightly higher than normal. Generally, our measurements yield values higher than those previously determined. These data, together with those available for the Variscan massifs of the northwestern Mediterranean, were used for constructing models of distribution of radiogenic heat production of the crust. The lithologic composition was deduced from available P-wave velocity data, by taking into account the pressure and temperature effects. Depending on the rate of decrease with depth of the radiogenic heat, the crustal contribution in terms of heat flux ranges from 26 to 39 mW m -2, and on average is 33 mW m -2. The mean heat production of the crust is 1.0 ?W m -3. Both average crustal heat source and crustal heat contribution are quite similar to those estimated with the heat-production-seismic velocity relationship.

Verdoya, M.; Pasquale, V.; Chiozzi, P.; Kukkonen, I. T.

1998-06-01

245

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

246

Use of limited daily access to food in measuring the heat production associated with food intake in laying hens  

Microsoft Academic Search

1. Two experiments were carried out to determine the heat production associated with food intake in laying hens allowed access to food for one (experiment 2) or two hours (experiment 1) daily.2. In experiment 1, heat production in the fed state was measured for two successive days after 46 h of food deprivation. The rate of heat production in the

Yuzhi Li; Toshio Ito; Sadaki Yamamoto

1991-01-01

247

Effect of chloride salts, curing compounds and heating and freezing on Trichinella spiralis in pork products  

E-print Network

EFFECT OF CHLORIDE SALTS, CURING COMPOUNDS AND HEATING AND FREEZING ON TRICHINELLA SPIRALIS IN PORK PRODUCTS A Thesis by TIMOTHY JON KAYFUS Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement... for the degree of MASTER OF SCIENCE August 1981 Major Subject: Food Science and Technology EFFECT OF CHLORIDE SALTS, CURING COMPOUNDS AND HEATING AND FREEZING ON TRICHINELLA SPIRALIS IN PORK PRODUCTS A Thesis by TIMOTHY JON KAYFUS Approved as to style...

Kayfus, Timothy Jon

2012-06-07

248

A (S)TEM gas cell holder with localized laser heating for in situ experiments.  

PubMed

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. PMID:23452391

Mehraeen, Shareghe; McKeown, Joseph T; Deshmukh, Pushkarraj V; Evans, James E; Abellan, Patricia; Xu, Pinghong; Reed, Bryan W; Taheri, Mitra L; Fischione, Paul E; Browning, Nigel D

2013-04-01

249

s the summer heats up, many people will head to local lakes to refresh themselves. In a temperate  

E-print Network

den- sity stratification, is often a dominating influence on the physics of lakes and oceansA s the summer heats up, many people will head to local lakes to refresh themselves. In a temperate climate, the surface layer of a lake often warms to above 20 °C. However, if you were to dive down

Wehrli, Bernhard

250

Constituting the space for decision making—Conflicting calculations in a dispute over fuel choice at a local heating plant  

Microsoft Academic Search

The paper focuses on the role of economic calculations in a dispute over the use of an alternative fuel at a heating plant. Our emphasis is on the spatial effects of the calculations: on the interplay between distanciated, standardised knowledge and local interpretations. Our conclusion is that the calculations were not only passive resources for argumentation but became performative during

Maria Åkerman; Taru Peltola

2006-01-01

251

Local heat-transfer characteristics of a row of circular air jets impinging on a concave semicylindrical surface  

NASA Technical Reports Server (NTRS)

An experimental study was made of the local heat-transfer characteristics of air jets impinging on the concave side of a right circular semicylinder. A correlation was developed for expressing individual and combined effects of a number of dimensionless variables on the normalized Nusselt number distributions. Results of the present study are in good agreement with those of other investigators.

Livingood, J. N. B.; Gauntner, J. W.

1973-01-01

252

Validity of the local thermal equilibrium assumption in streambeds: implications for the use of heat as a tracer  

NASA Astrophysics Data System (ADS)

Analytical solutions of the heat transport equation have been extensively used to model heat exchange in streambeds and for inferring pore water flow velocities from streambed temperature data. One of the underlying assumptions to derive such analytical solutions is that of Local Thermal Equilibrium (LTE) between fluid and solids. By examining experimental and theoretical relationships of the fluid-solid heat transfer coefficient in a numerical scheme and deriving a correlation for the heat transfer coefficient at low Re numbers using available experimental data, we show that LTE is not attained for Re numbers below 0.01. From the results of this study, it was observed that the processes of heat advection and heat transfer (between solid grains and fluid) act against each other: while increased advective heat transport tends to cause disequilibrium, heat transfer between the phases tends to move the system towards equilibrium. At higher velocities (Re > 0.01), more effective heat transfer between the phases outweighs the effect of the advective heat transport and equilibrium is therefore reached almost instantaneously. As Re decreases (decrease in velocity) the heat transfer coefficient reduces leading to larger disequilibrium between phases. In addition the analysis emphasizes that as the ratio of solid to fluid thermal conductivity increases (Ks/Kf > 1) the temperature difference between water and solid phases also increases. As a result of thermal disequilibrium (i.e. temperature differences between solid and fluid phases), significant errors are induced in velocity estimates when inverting streambed temperature data assuming LTE especially at relatively lower Re values. Therefore assuming LTE may undermine conceptual understandings of streambed thermal processes relevant to stream ecology and biogeochemistry.

Roshan, H.; Cuthbert, M. O.; Andersen, M. S.; Acworth, R. I.

2013-12-01

253

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

254

Heat production in human skeletal muscle at the onset of intense dynamic exercise  

PubMed Central

We hypothesised that heat production of human skeletal muscle at a given high power output would gradually increase as heat liberation per mole of ATP produced rises when energy is derived from oxidation compared to phosphocreatine (PCr) breakdown and glycogenolysis.Five young volunteers performed 180 s of intense dynamic knee-extensor exercise (?80 W) while estimates of muscle heat production, power output, oxygen uptake, lactate release, lactate accumulation and ATP and PCr hydrolysis were made. Heat production was determined continuously by (i) measuring heat storage in the contracting muscles, (ii) measuring heat removal to the body core by the circulation, and (iii) estimating heat transfer to the skin by convection and conductance as well as to the body core by lymph drainage.The rate of heat storage in knee-extensor muscles was highest during the first 45 s of exercise (70-80 J s?1) and declined gradually to 14 ± 10 J s?1 at 180 s. The rate of heat removal by blood was negligible during the first 10 s of exercise, rising gradually to 112 ± 14 J s?1 at 180 s. The estimated rate of heat release to skin and heat removal via lymph flow was < 2 J s?1 during the first 5 s and increased progressively to 24 ± 1 J s?1 at 180 s.The rate of heat production increased significantly throughout exercise, being 107 % higher at 180 s compared to the initial 5 s, with half of the increase occurring during the first 38 s, while power output remained essentially constant.The contribution of muscle oxygen uptake and net lactate release to total energy turnover increased curvilinearly from 32 % and 2 %, respectively, during the first 30 s to 86 % and 8 %, respectively, during the last 30 s of exercise. The combined energy contribution from net ATP hydrolysis, net PCr hydrolysis and muscle lactate accumulation is estimated to decline from 37 % to 3 % comparing the same time intervals.The magnitude and rate of elevation in heat production by human skeletal muscle during exercise in vivo could be the result of the enhanced heat liberation during ATP production when aerobic metabolism gradually becomes dominant after PCr and glycogenolysis have initially provided most of the energy. PMID:10766936

González-Alonso, José; Quistorff, Bjørn; Krustrup, Peter; Bangsbo, Jens; Saltin, Bengt

2000-01-01

255

Arabidopsis HIT4 encodes a novel chromocentre-localized protein involved in the heat reactivation of transcriptionally silent loci and is essential for heat tolerance in plants.  

PubMed

The Arabidopsis mutant heat-intolerant 4-1 (hit4-1) was isolated from an ethyl methanesulphonate-mutagenized M2 population on the basis of its inability to withstand prolonged heat stress (4 days at 37°C). Further characterization indicated that hit4-1 was impaired specifically in terms of basal but not acquired thermotolerance. Map-based cloning revealed that the HIT4 gene encoded a plant-specific protein for which the molecular function has yet to be studied. To investigate the cellular role of HIT4 and hence elucidate better its protective function in heat tolerance in plants, a GFP-HIT4 reporter construct was created for a protoplast transient expression assay. Results showed that fluorescently tagged HIT4 was localized to the chromocentre, a condensed heterochromatin domain that harbours repetitive elements for which transcription is normally suppressed by transcriptional gene silencing (TGS). DAPI-staining analysis and FISH with a probe that targeted centromeric repeats showed that heat-induced chromocentre decondensation was inhibited in nuclei of hit4-1 subjected to direct heat treatment, but not in those that were allowed to acquire thermotolerance. Moreover, heat reactivation of various TGS loci, regardless of whether they were endogenous or transgenic, or existed as a single copy or as repeats, was found to be attenuated in hit4-1. Meanwhile, the levels of transcripts of heat shock protein genes in response to heat stress were similar in both hit4-1 and wild-type plants. Collectively, these results demonstrated that HIT4 defines a new TGS regulator that acts at the level of heterochromatin organization and is essential for basal thermotolerance in plants. PMID:23408827

Wang, Lian-Chin; Wu, Jia-Rong; Chang, Wei-Ling; Yeh, Chin-Hui; Ke, Yi-Ting; Lu, Chun-An; Wu, Shaw-Jye

2013-04-01

256

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

257

Molecular cloning, expression and localization of human 105 kDa heat shock protein, hsp105  

Microsoft Academic Search

We have shown that the 105 kDa heat shock protein (hsp105?) and hsp105? (42°C-specific heat shock protein) constitute high molecular mass (HMM) heat shock proteins (HSPs) in mouse cells. However, since HMM HSPs have not been identified in human cells, we screened a cDNA library constructed with poly(A)+ RNA derived from heat-shocked human HeLa cells using mouse hsp105? cDNA. Two

Keiichi Ishihara; Kunihiko Yasuda; Takumi Hatayama

1999-01-01

258

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

259

CARTOGRAPHIC LANGUAGE AND PRODUCTION OF KNOWLEDGE: TEACHING LOCAL GEOGRAPHY WITH A MUNICIPAL SCHOOL ATLAS  

Microsoft Academic Search

At events on School Cartography in Brazil, local school atlases have been one of the subjects most frequently presented. However, further research is necessary to elucidate how these materials can be used in teachers' practices. To this end, a collaborative research was conducted involving fifteen teachers, to investigate the production of knowledge about space based on a local atlas. This

Rosângela Doin de Almeida

260

Flight energetics in sphinx moths: heat production and heat loss in Hyles lineata during free flight.  

PubMed

1. Mean thoracic temperature of free-flying H. lineata in the field and in the laboratory increased from about 40 degrees C at Ta=16 degrees C to 42-5 degrees C at Ta=32 degrees C. At a given Ta, thoracic temperature was independent of body weight and weakly correlated with wing loading. 2. The difference between abdominal temperature and air temperature increased from 2 degrees C at low Ta to 4-2 degrees C at high Ta. At a given Ta, the difference between Tab and Ta was positively correlated with thoracic temperature. 3. Oxygen consumption per unit weight did not appear to vary with Ta from 15 to 30 degrees C and was inversely proportional to body weight. 4. Thermal conductance of the abdomen (Cab) was greater than thermal conductance of the thorax (Cth) in still air and at wind velocities up to 2-5 m/s. In moving air at speeds approximating flight, Cth was twice as high as in still air. Under the same conditions Cab was 3-4 times as high as in still air. 5. Thoracic and abdominal conductance are inversely proportional to their respective weights. 6. These data are consistent with the hypothesis that thoracic temperature is controlled by regulation of heat loss. However, a heat budget derived from these data suggests that heat dissipation may not be sufficient to offset the decrease in passive cooling of the thorax at high ambient temperatures. PMID:932632

Casey, T M

1976-06-01

261

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

262

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...

263

Optimization and heat and water integration for biodiesel production  

E-print Network

generation of biodiesel using waste cooking oil and algae oil. We consider 5 different technologies.42$/gal, 1.94 MJ/gal of energy consumption and freshwater consumption 0.60 galwater / galethanol Among oils, waste cooking oil is a promising alternative to vegetable oil for biodiesel production

Grossmann, Ignacio E.

264

Technologies for production of Electricity and Heat in Sweden  

E-print Network

there was a battle between wind turbine concepts, but the commercial winner today is the three-bladed horizontal axis, upwind, electricity producing and grid connected wind turbine with availability on mature markets, operation and maintenance costs, electricity production and turbine lifetime. An average turbine installed

265

Immediate Warning of Local Overheating in Electric Machines by the Detection of Pyrolysis Products  

Microsoft Academic Search

A device employing an ion chamber has been developed for the sensitive, reliable, and very rapid detection of local ovetheatingin a gas-cooled electric machine before extensive damage can result. The device detects the presence of pyrolysis products generated by the thermal decomposition of organic materials such as insulations and polymers. The pyrolysis products include particles of the size of condensation

C. C. Carson; S. C. Barton; F. S. Echeverria

1973-01-01

266

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

267

CONSUMERS' WILLINGNESS TO PURCHASE LOCALLY PRODUCED AGRICULTURAL PRODUCTS: AN ANALYSIS OF AN INDIANA SURVEY  

Microsoft Academic Search

Using a survey of over 320 consumers from across the state of Indiana, we estimate an ordered probit model to determine the demographic and attitudinal factors which are most important in predicting the likelihood of consumers to purchase products that are produced within the state. Our results indicate that the willingness to purchase locally produced agricultural products increases with time

Mark D. Jekanowski; Daniel R. Williams II; William A. Schiek

2000-01-01

268

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

269

Investigations concerning nuclear energy in the combined production of electricity and heat in the Helsinki metropolitan area  

Microsoft Academic Search

The possibility of producing the base load of both electricity and district heat for the Helsinki Metropolitan Area (HMA) utilizing nuclear energy has been investigated since 1968. At every stage of the study, it has been concluded that district heating utilizing nuclear power in combined electricity and heat productions is the most economical way of heating the main part of

M. Aho; H. Hiidenpalo; M. Seppae; O. J. A. Tiainen

1978-01-01

270

IMPROVEMENTS IN THE MEASUREMENTS OF HEAT AND FRESH WATER THROUGH THE BERING STRAIT: A PRODUCT OF RUSALCA  

E-print Network

IMPROVEMENTS IN THE MEASUREMENTS OF HEAT AND FRESH WATER THROUGH THE BERING STRAIT: A PRODUCT. For reference, note that the Bering Strait oceanic heat flux is comparable to heat flux into the ocean from the atmosphere in the Chukchi, and that the Bering Strait oceanic heat flux likely acts as a trigger

271

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

272

Assessment of combined heat and power (CHP) integrated with wood-based ethanol production  

Microsoft Academic Search

A techno-economic assessment is made of wood-based production of ethanol, where the by-products are used for internal energy needs as well as for generation of electricity, district heat and pelletised fuel in different proportions for external use. Resulting ethanol production costs do not differ much between the options but a process where electricity generation is maximised by use of the

Gunnar Eriksson; Björn Kjellström

2010-01-01

273

The kinetics of heat production in response to active shortening in frog skeletal muscle.  

PubMed Central

1. Tension and heat production were measured at 0 degree C in sartorius muscles from Rana temporaria in response to two extents of shortening at five velocities. Shortening was from approximately 2.4 to 2.2 microns, 2.4 to 2.3 microns and 2.3 to 2.2 micron at velocities per half-sarcomere from 0.2 to 1.56 micron s-1. 2. Tension became approximately constant at all velocities. Records of heat rate obtained by differentiating traces from which thermoelastic heat had been subtracted became negative early in shortening and then rose. Heat rate became constant during shortening only at the lowest velocity and was still rising at the end of shortening at higher velocities. The highest heat rate occurred at the end of shortening at the two highest velocities. At the end of shortening at all velocities heat rate gradually approached the isometric level measured at the short length, the half-time for decline being largest following the slowest larger shortening. 3. Heat produced as a consequence of shortening but not associated with tension recovery was determined by subtracting shortening heat measured in response to two extents of shortening to the same muscle length. The differences in shortening heat continued to increase after shortening ended, and more of the extra heat produced in response to shortening appeared after the end of rapid shortening than during shortening itself. 4. Shortening heat coefficients calculated in different ways were similar to coefficients determined in previous studies. Coefficients calculated from measurements that excluded heat produced by tension recovery and allowed for continued production of heat by processes initiated by shortening were found to increase linearly with the force maintained during shortening. 5. The results show that the kinetics of heat production during and after shortening are very sensitive to the speed of shortening and that steady rates of energy liberation are not attained during shortening of less than or equal to 10% of muscle length at velocities greater than or equal to 12% of maximum velocity. PMID:3498824

Ford, L E; Gilbert, S H

1987-01-01

274

Simulated and Observed Influence of the Nocturnal Urban Heat Island on the Local Wind Field  

Microsoft Academic Search

A three-dimensional primative equation model was used to simulate the low-level wind field, given the urban heat island as the lower temperature boundary condition. The specification of the average heat island bypassed the need to calculate the surface energy budget, considerably simplifying the model. This is especially desirable since temperature is a more accurate and easily obtainable measurement. The influence

Roland R. Draxler

1986-01-01

275

Transients in flow and local heat transfer due to a pressure wave in pipe flow  

Microsoft Academic Search

The effect of a pressure wave on the turbulent flow and heat transfer in a rectangular air flow channel has been experimentally studied for fast transients, occurring due to a sudden increase of the main flow by an injection of air through the wall. A fast response measuring technique using a hot film sensor for the heat flux, a hot

R. J. VAN DER LINDEN; C. J. Hoogendoorn

1994-01-01

276

An analytical study of local thermal equilibrium in porous heat sinks using fin theory  

Microsoft Academic Search

This work presents an algorithm model for estimating the heat transfer by forced convection of the porous heat sink in a channel by applying the fin theory and the concept of the thermal network. The proposed algorithm model is simpler and more convenient than numerical analysis. By comparison with numerical calculations and other experiments, the model was verified to predict

Tzer-Ming Jeng; Sheng-Chung Tzeng; Ying-Huei Hung

2006-01-01

277

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

278

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 percent 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 percent higher than the corresonding leeward side.

Morehouse, Kim A.; Simoneau, Robert J.

1986-01-01

279

Production of heat shock proteins, cytokines, and nitric oxide in toxic stress  

Microsoft Academic Search

Expression of heat shock proteins Hsp27, Hsp90, and Hsp70 and production of tumor necrosis factors (TNF-?, TNF-?), interferon-?\\u000a (IFN-?), interleukin-2,-3,-6, and nitric oxide (NO) were studied under conditions of acute and chronic intoxication of animals\\u000a with lipopolysaccharides. Injection of endotoxin increased expression of heat shock proteins Hsp70 and Hsp90-? in mouse cells.\\u000a Acute toxic stress also provoked a sharp increase

E. G. Novoselova; O. V. Glushkova; D. A. Cherenkov; S. B. Parfenyuk; T. V. Novoselova; S. M. Lunin; M. O. Khrenov; I. V. Guzhova; B. A. Margulis; E. E. Fesenko

2006-01-01

280

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

2007-08-27

281

Local heat transfer distribution between smooth flat surface and impinging air jet from a circular nozzle at low Reynolds numbers  

Microsoft Academic Search

An experimental investigation is performed to study the effect of jet to plate spacing and low Reynolds number on the local\\u000a heat transfer distribution to normally impinging submerged circular air jet on a smooth and flat surface. A single jet from\\u000a a straight circular nozzle of length-to-diameter ratio (l\\/d) of 83 is tested. Reynolds number based on nozzle exit condition

Vadiraj V. Katti; S. Nagesh Yasaswy; S. V. Prabhu

2011-01-01

282

Initial Evaluation of the Heat-Affected Zone, Local Embrittlement Phenomenon as it Applies to Nuclear Reactor Vessels  

SciTech Connect

The objective of this project was to determine if the local brittle zone (LBZ) problem, encountered in the testing of the heat-affected zone (HAZ) part of welds in offshore platform construction, can also be found in reactor pressure vessel (RPV) welds. Both structures have multipass welds and grain coarsening along the fusion line. Literature was obtained that described the metallurgical evidence and the type of research work performed on offshore structure welds.

McCabe, D.E.

1999-09-01

283

Determination of Local Experimental Heat-Transfer Coefficients on Combustion Side of an Ammonia-Oxygen Rocket  

NASA Technical Reports Server (NTRS)

Local experimental heat-transfer coefficients were measured in the chamber and throat of a 2400-pound-thrust ammonia-oxygen rocket engine with a nominal chamber pressure of 600 pounds per square inch absolute. Three injector configurations were used. The rocket engine was run over a range of oxidant-fuel ratio and chamber pressure. The injector that achieved the best performance also produced the highest rates of heat flux at design conditions. The heat-transfer data from the best-performing injector agreed well with the simplified equation developed by Bartz at the throat region. A large spread of data was observed for the chamber. This spread was attributed generally to the variations of combustion processes. The spread was least evident, however, with the best-performing injector.

Liebert, Curt H.; Ehlers, Robert C.

1961-01-01

284

A proposed new method for inferred geothermal resource estimates: Heat in Place Density and local Sustainable Pumping Rates  

NASA Astrophysics Data System (ADS)

Heat in place analysis and estimates of sustainable pumping rate are standard methods in geothermal exploration of hot sedimentary aquifers and enhanced geothermal systems. Shortcomings of the standard method are: (1) the available heat in place is evaluated for a whole resource area (large scale), obliterating gradient information in available heat; (2) sustainable pumping rates are only performed for one particular target location (local scale) rather than providing a map of sustainable rates for the entire reservoir. Both factors are important for assessing the choice of location and commercial viability of a potential geothermal plant. We present here a method to overcome this scale dependence and propose that it is possible to evaluate both heat in place and estimates of sustainable pumping rate on a map basis. Our approach is integrated into a workflow that incorporates geological modeling and fluid and heat flow simulation of a broad resource area. The results of the simulation are used to evaluate the heat in place density at every location. To upscale the estimations of sustainable pumping rates, we developed an approach that allows location-based calculations everywhere in the resource area, also taking into account the results of the flow simulation. We thus obtain maps for both factors. These can be directly used to analyze viability of promising targets. We apply our workflow and analysis to a typical hot sedimentary aquifer setting and demonstrate the application from the initial geological modeling to the flow simulation and finally maps of heat in place density and sustainable pumping rates. As the analyses are integrated into one workflow, a direct model and analyses update is possible when new data becomes available. It is thus an ideal tool for early exploration stages. As our approach resolves the scale difference between heat in place and sustainable pumping rate estimates, and provides both analyses in a map view, it has the potential to be a valuable tool to identify optimal targets in a hot sedimentary aquifer resource area.

Florian Wellmann, J.; Horowitz, Franklin G.; Deckert, Hagen; Regenauer-Lieb, Klaus

2010-05-01

285

Productivity, innovation strategies and industrial relations in SMEs. Empirical evidence for a local production system in northern Italy  

Microsoft Academic Search

The paper aims to provide an original contribution to evaluating several kinds of relations between four areas of innovation activities – training, technology, organization, ICT (information and communication technologies) – and industrial relations and firm’s economic performance. Quantitative evidence for a SME?based local production system is provided by exploiting two datasets: the first is derived from a direct survey carried

Davide Antonioli; Massimiliano Mazzanti; Paolo Pini

2010-01-01

286

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

287

Localized dryout: An approach for managing the thermal hydrologi-cal effects of decay heat at Yucca Mountain  

SciTech Connect

For a nuclear waste repository in the unsaturated zone at Yucca Mountain, there are two thermal loading approaches to using decay heat constructively -- that is, to substantially reduce relative humidity and liquid flow near waste packages for a considerable time, and thereby limit waste package degradation and radionuclide dissolution and release. ``Extended dryout`` achieves these effects with a thermal load high enough to generate large-scale (coalesced) rock dryout. ``Localized dryout``(which uses wide drift spacing and a thermal load too low for coalesced dryout) achieves them by maintaining a large temperature difference between the waste package and drift wall; this is done with close waste package spacing (generating a high line-heat load) and/or low-thermal-conductivity backfill in the drift. Backfill can greatly reduce relative humidity on the waste package in both the localized and extended dryout approaches. Besides using decay heat constructively, localized dryout reduces the possibility that far-field temperature rise and condensate buildup above the drifts might adversely affect waste isolation.

Buscheck, T. A.; Nitao, J.J.; Ramspott, L.D.

1995-11-01

288

Gold nanorod-facilitated localized heating of droplets in microfluidic chips.  

PubMed

A gold nanorod-facilitated optical heating method for droplets in microfluidic chips is reported. Individual and stream nanoliter level droplets containing gold nanorods are heated by a low power 808-nm-wavelength laser. Owing to the high photothermal conversion efficiency of gold nanorods, a droplet temperature of 95 °C is achieved by employing a 13.6 mW laser with good reproducibility. The heating and cooling times are 200 and 800 ms, respectively, which are attributed to the fast thermal-transfer rates of the droplets. By controlling the irradiation laser power, the temperature cycles for polymerase chain reaction are also demonstrated. PMID:23389021

Li, Zhiyong; Wang, Pan; Tong, Limin; Zhang, Lei

2013-01-14

289

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

290

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

291

Heat treatment of retinal pigment epithelium induces production of elastic lamina components and antiangiogenic activity  

PubMed Central

Age-related macular degeneration (AMD) is the leading cause of blindness in the Western world. In advanced AMD, new vessels from choriocapillaris (CC) invade through the Bruch's membrane (BrM) into the retina, forming choroidal neovascularization (CNV). BrM, an elastic lamina that is located between the retinal pigment epithelium (RPE) and CC, is thought to act as a physical and functional barrier against CNV. The BrM of patients with early AMD are characterized by decreased levels of antiangiogenic factors, including endostatin, thrombospondin-1 (TSP-1), and pigment epithelium-derived factor (PEDF), as well as by degeneration of the elastic layer. Motivated by a previous report that heat increases elastin expression in human skin, we examined the effect of heat on human ARPE-19 cell production of BrM components. Heat treatment stimulated the production of BrM components, including TSP-1, PEDF, and tropoelastin in vitro and increased the antiangiogenic activity of RPE measured in a mouse corneal pocket assay. The effect of heat on experimental CNV was investigated by pretreating the retina with heat via infrared diode laser prior to the induction of CNV. Heat treatment blocked the development of experimental CNV in vivo. These findings suggest that heat treatment may restore BrM integrity and barrier function against new vessel growth.—Sekiyama, E., Saint-Geniez, M., Yoneda, K., Hisatomi, T., Nakao, S., Walshe, T. E., Maruyama, K., Hafezi-Moghadam, A., Miller, J. W., Kinoshita, S., D'Amore, P. A. Heat treatment of retinal pigment epithelium induces production of elastic lamina components and anti-angiogenic activity. PMID:22067481

Sekiyama, Eiichi; Saint-Geniez, Magali; Yoneda, Kazuhito; Hisatomi, Toshio; Nakao, Shintaro; Walshe, Tony E.; Maruyama, Kazuichi; Hafezi-Moghadam, Ali; Miller, Joan W.; Kinoshita, Shigeru; D'Amore, Patricia A.

2012-01-01

292

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

E-print Network

21 Heat Transfer Distribution for et=90', Re = 1. 0x10, M = 2. 0 and D/W = 0. 2 39 Nu/Nu?t 0 5. 27 6. 13 7. 40 8. 76 Flow Direction Figure 22 Heat Transfer Distribution for u=45', Re = 5. 0x10, M = 0. 75 and D/W = 0. 1 40 Nu/Nu?r 0 4. 42 5. 39... 21 Heat Transfer Distribution for et=90', Re = 1. 0x10, M = 2. 0 and D/W = 0. 2 39 Nu/Nu?t 0 5. 27 6. 13 7. 40 8. 76 Flow Direction Figure 22 Heat Transfer Distribution for u=45', Re = 5. 0x10, M = 0. 75 and D/W = 0. 1 40 Nu/Nu?r 0 4. 42 5. 39...

Adewusi, Adedapo Oluyomi

2012-06-07

293

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

294

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

295

A simplified method for thermal analysis of a cowl leading edge subject to intense local shock-wave-interference heating  

NASA Technical Reports Server (NTRS)

Type IV shock wave interference heating on a blunt body causes extremely intense heating over a very localized region of the body. An analytical solution is presented to a heat transfer problem that approximates the shock wave interference heating of an engine cowl leading edge of the National Aero-Space Plane. The problem uses a simplified geometry to represent the leading edge. An analytical solution is developed that provides a means for approximating maximum temperature differences between the outer and inner surface temperatures of the leading edge. The solution is computationally efficient and, as a result, is well suited for conceptual and preliminary design or trade studies. Transient and steady state analyses are conducted, and results obtained from the analytical solution are compared with results of 2-D thermal finite element analyses over a wide range of design parameters. Isotropic materials as well as laminated composite materials are studied. Results of parametric studies are presented to indicate the effects of the thickness of the cowl leading edge and the width of the region heated by the shock wave interference on the thermal response of the leading edge.

Mcgowan, David M.; Camarda, Charles J.; Scotti, Stephen J.

1992-01-01

296

The production of activated carbon using the equipment of thermal power plants and heating plants  

NASA Astrophysics Data System (ADS)

The production technology of activated carbon using the conventional equipment of the thermal power stations and boiler houses is proposed. The obtained product is directed into the systems of chemical water preparation and water drain of enterprises. The production cycle is invariable when producing the activated carbon by the proposed technology. The fuel consumption and heat losses are considerably reduced when implementing this technology compared with the known analogs of the carbon sorbent. The production efficiency increases if small dust particles are preliminary separated and coal is activated in narrow ranges of fraction sizes.

Osintsev, K. V.; Osintsev, V. V.; Dzhundubaev, A. K.; Kim, S. P.; Al'musin, G. T.; Akbaev, T. A.; Bogatkin, V. I.

2013-08-01

297

Nuclear data production, calculation and measurement: a global overview of the gamma heating issue  

NASA Astrophysics Data System (ADS)

The gamma heating evaluation in different materials found in current and future generations of nuclear reactor (EPRTM, GENIV, MTR-JHR), is becoming an important issue especially for the design of many devices (control rod, heavy reflector, in-core & out-core experiments…). This paper deals with the works started since 2009 in the Reactor Studies Department of CEA Cadarache in ordre to answer to several problematic which have been identified as well for nuclear data production and calculation as for experimental measurement methods. The selected subjects are: Development of a Monte Carlo code (FIFRELIN) to simulate the prompt fission gamma emission which represents the major part of the gamma heating production inside the core Production and qualification of new evaluations of nuclear data especially for radiative capture and inelastic neutron scattering which are the main sources of gamma heating out-core Development and qualification of a recommended method for the total gamma heating calculation using the Monte Carlo simulation code TRIPOLI-4 Development, test and qualification of new devices dedicated to the in-core gamma heating measurement as well in MTR-JHR as in zero power facilities (EOLE-MINERVE) of CEA, Cadarache to increase the experimental measurement accuracy.

Colombier, A.-C.; Amharrak, H.; Fourmentel, D.; Ravaux, S.; Régnier, D.; Gueton, O.; Hudelot, J.-P.; Lemaire, M.

2013-03-01

298

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

299

Stimulation of cysteinyl leukotriene production in mast cells by heat shock and acetylsalicylic acid.  

PubMed

Immunoglobulin (Ig) E-dependent activation of mast cells is central to the allergic response. The engagement of IgE-occupied receptors initiates a series of molecular events that causes the release of preformed, and de novo synthesis of, allergic mediators. Cysteinyl leukotrienes are able to contract airway smooth muscle and increase mucus secretion and vascular permeability and recruit eosinophils. Mast cells have also recently been recognized as active participants in innate immune responses. Heat stress can modulate innate immunity by inducing stress proteins such as heat-shock proteins (HSPs). We previously demonstrated that treatment of mast cells with heat shock or acetylsalicylic acid results in an increase of TNF-alpha and IL-6 release. This effect was paralleled by expression of HSP70. In the current study, we further investigated the effects of heat shock and acetylsalicylic acid on the activation of mast cells and the release of cysteinyl leukotrienes. In mouse mast cells, derived from a culture of bone marrow cells, responsiveness to heat shock, acetylsalicylic acid and exogenous or endogenous HSP70 was monitored by measuring leukotriene C4 release. We show that after heat shock treatment and exposure to acetylsalicylic acid leukotriene production was increased. Moreover, exogenous rHSP70 also induced leukotriene production. Because it has been reported that leukotriene production in mast cells may be mediated by Toll like receptor (TLR) activation, and HSP70 also activates TLRs signaling, we further explored these issues by using mast cells that are not able to produce HSP70, i.e. heat shock factor-1 (HSF-1) knockout cells. We found that in HSF-1 knockout bone marrow derived mast cells, heat shock and acetylsalicylic acid failed to induce release of leukotrienes. Moreover, in wild type cells the surface expression of TLR4 was attenuated, whereas the intracellular expression was up-regulated. We conclude that heat shock and acetylsalicylic acid induce the production and release of heat shock proteins from mast cells, which in turn stimulate leukotriene synthesis through activation of TLR4. PMID:17306251

Mortaz, Esmaeil; Redegeld, Frank A; Dunsmore, Kathy; Odoms, Kelli; Wong, Hector R; Nijkamp, Frans P; Engels, Ferdi

2007-04-30

300

Factors affecting aerobic recovery heat production and recovery ratio of frog sartorius.  

PubMed Central

1. Sartorius muscles of Rana temporaria, equilibrated at 20 degrees C in Ringer solution buffered with phosphates, were stimulated isometrically for 0.2 up to 0.75 s at lengths varying from 1.03 to 1.48 times rest length, L0. The aerobic recovery heat was measured for 10.5 min after contraction. 2. The recovery heat production had a complex time course, showing a variable delay to maximum, declining thereafter. In most cases, the rate of heat production did not decrease monotonically; attention was focused on the slow exponential decay which only persisted from 1.5-5 min after contraction. This latter part of the time course was considered as strictly aerobic and characterized by the time constant tau s. 3. Increasing the tetanus duration from 0.2 to 0.75 s increased initial heat Qi and recovery heat Qr in proportion, so that the recovery ratio R (Qr/Qi) did not change; it was equal to 1.29 +/- 0.03 (S.E.M.; n = 44) for muscles at about L0. The kinetics of heat production were modified with longer tetani; in particular, tau s was increased from 2.2 to 5.2 min. 4. When muscles were stretched beyond L0, as long as there was no increase of the resting heat rate (stretch response or 'Feng effect'), recovery heat production had a similar evolution to that in muscles at about L0; R was constant and equal to 1.21 +/- 0.03 (n = 46). 5. When muscles were sufficiently stretched to develop a stretch response, R increased proportionally to the stretch response. The effect seemed independent of the contractile machinery, as it vanished concomitantly with the stretch response, while force and Qi remained unchanged for the length considered. The kinetics were also modified--the delay to maximum was no longer detected and tau s most likely increased. 6. Substitution of 60% of the NaCl of the Ringer solution by NaI (mol/mol) produced a significant increase of R, mainly due to the increase of Qr. 7. The results show that neither the time course nor the amount of aerobic recovery heat Qr are strictly determined by the amount of initial heat Qi. The hypothesis is discussed that Qr might include a variable fraction due to processes which are not directly implicated in the actin-myosin interactions, possibly those involving the cytosolic Ca2+ concentration and the rate of resting metabolism. Images Fig. 3 PMID:2621637

Godfraind-De Becker, A

1989-01-01

301

Targeting the Local: Policing Clandestine Methamphetamine Production in a Rural US Community  

Microsoft Academic Search

In the United States, state-based efforts to curtail the spread of methamphetamine (“meth”) have targeted domestic producers through heightened regulation of precursor chemicals used in the clandestine meth-production process. This article examines the impact of these efforts on the exercise of police power in a rural community affected by methamphetamine. As the author shows, the targeting of local meth production

William Garriott

2010-01-01

302

Rejection of waste heat from oxygen liquefaction operations at a lunar oxygen production plant  

NASA Astrophysics Data System (ADS)

Oxygen liquefaction is a key processing step of proposed lunar oxygen production plants. A baseline oxygen liquefaction process has been developed. The process operates continuously with a production rate of 200 tonnes per year. Oxygen is liquefied using a cascade refrigeration scheme in which methane and ethane refrigeration loops are used to increase the rejection temperature to 270 K. Heat is transferred from three process coolers to a utility cooling fluid and subsequently rejected by conduction to the lunar subsurface. An initial subsurface regolith exchanger consists of smooth tubes buried horizontally at a depth of about 2 m. A heat transfer analysis is performed to determine approximations for the spacing required between parallel tubes and the required heat exchange area.

Linsley, J. N.; Jenson, E. B.

303

Local thermal non-equilibrium in sediments: Implications for temperature dynamics and the use of heat as a tracer  

NASA Astrophysics Data System (ADS)

Understanding streambed thermal processes is of fundamental importance due to the effects of temperature dynamics on stream ecology and solute exchange processes. Local Thermal Equilibrium (LTE) between fluid and solid is usually assumed for modelling heat exchange in streambeds and for inferring pore water flow velocities from streambed temperature data. By examining well established experimental and theoretical relationships of the fluid-solid heat transfer coefficient in a numerical scheme for a range of Reynolds (Re) numbers (0.01 > Re > 0.001), we show here that, for a range of typical streambed conditions, LTE is not attained. Thus errors in velocity estimates obtained when inverting streambed temperature data assuming LTE can be considerable especially at relatively low flow rates. We show that for certain conditions were the LTE assumption is not valid, inferred pore water velocities of up to 1 m/d can be obtained with LTE assumption even if the actual velocities are much smaller or even zero. Ignoring the possibility of Local Thermal Non-Equilibrium (LTNE) will have consequences for the correct estimation of streambed pore water velocity and heat fluxes at low Re values. More laboratory studies are urgently needed to supplement the sparse existing data in this area and further test the findings of this study

Roshan, H.; Cuthbert, M. O.; Andersen, M. S.; Acworth, R. I.

2014-11-01

304

Small scale porous medium combustion system for heat production in households  

Microsoft Academic Search

For heating purposes in modern households, gas burners are normally applied due to their simplicity, low cost and easy handling. On the other hand, practical experience showed that conventional, open flame gas burners compared to porous medium systems have low dynamic range, i.e. low power modulation capability and, additionally, higher production of pollutants such as carbon monoxide (CO) and nitrogen

F. Avdic; M. Adzic; F. Durst

2010-01-01

305

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

306

Temperature-Humidity Indices as Indicators of Milk Production Losses due to Heat Stress  

Microsoft Academic Search

Meteorological data (1993 to 2004) from 2 public weather stations in Phoenix, Arizona, and Athens, Georgia, were analyzed with test day milk yield data from herds near weather stations to identify the most appropriate temperature-humidity index (THI) to mea- sure losses in milk production due to heat stress in the semiarid climate of Arizona and the humid climate of Georgia.

J. Bohmanova; I. Misztal; J. B. Cole

2007-01-01

307

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

308

Sex- and limb-specific differences in the nitric oxide-dependent cutaneous vasodilation in response to local heating.  

PubMed

Local heating of the skin is commonly used to assess cutaneous microvasculature function. Controversy exists as to whether there are limb or sex differences in the nitric oxide (NO)-dependent contribution to this vasodilation, as well as the NO synthase (NOS) isoform mediating the responses. We tested the hypotheses that 1) NO-dependent vasodilation would be greater in the calf compared with the forearm; 2) total NO-dependent dilation would not be different between sexes within limb; and 3) women would exhibit greater neuronal NOS (nNOS)-dependent vasodilation in the calf. Two microdialysis fibers were placed in the skin of the ventral forearm and the calf of 19 (10 male and 9 female) young (23 ± 1 yr) adults for the local delivery of Ringer solution (control) or 5 mM N(?)-propyl-l-arginine (NPLA; nNOS inhibition). Vasodilation was induced by local heating (42°C) at each site, after which 20 mM N(G)-nitro-l-arginine methyl ester (l-NAME) was perfused for within-site assessment of NO-dependent vasodilation. Cutaneous vascular conductance (CVC) was calculated as laser-Doppler flux/mean arterial pressure and normalized to maximum (28 mM sodium nitroprusside, 43°C). Total NO-dependent vasodilation in the calf was lower compared with the forearm in both sexes (Ringer: 42 ± 5 vs. 62 ± 4%; P < 0.05; NPLA: 37 ± 3 vs. 59 ± 5%; P < 0.05) and total NO-dependent vasodilation was lower in the forearm for women (Ringer: 52 ± 6 vs. 71 ± 4%; P < 0.05; NPLA: 47 ± 6 vs. 68 ± 5%; P < 0.05). NPLA did not affect total or NO-dependent vasodilation across limbs in either sex (P > 0.05). These data suggest that the NO-dependent component of local heating-induced cutaneous vasodilation is lower in the calf compared with the forearm. Contrary to our original hypothesis, there was no contribution of nNOS to NO-dependent vasodilation in either limb during local heating. PMID:25100074

Stanhewicz, Anna E; Greaney, Jody L; Larry Kenney, W; Alexander, Lacy M

2014-10-01

309

Muscle heat production and anaerobic energy turnover during repeated intense dynamic exercise in humans  

PubMed Central

The aim of the present study was to examine muscle heat production, oxygen uptake and anaerobic energy turnover throughout repeated intense exercise to test the hypotheses that (i) energy turnover is reduced when intense exercise is repeated and (ii) anaerobic energy production is diminished throughout repeated intense exercise. Five subjects performed three 3 min intense one-legged knee-extensor exercise bouts (EX1, EX2 and EX3) at a power output of 65 ± 5 W (mean ±s.e.m.), separated by 6 min rest periods. Muscle, femoral arterial and venous temperatures were measured continuously during exercise for the determination of muscle heat production. In addition, thigh blood flow was measured and femoral arterial and venous blood were sampled frequently during exercise for the determination of muscle oxygen uptake. Anaerobic energy turnover was estimated as the difference between total energy turnover and aerobic energy turnover. Prior to exercise, the temperature of the quadriceps muscle was passively elevated to 37.02 ± 0.12 °C and it increased 0.97 ± 0.08 °C during EX1, which was higher (P < 0.05) than during EX2 (0.79 ± 0.05 °C) and EX3 (0.77 ± 0.06 °C). In EX1 the rate of muscle heat accumulation was higher (P < 0.05) during the first 120 s compared to EX2 and EX3, whereas the rate of heat release to the blood was greater (P < 0.05) throughout EX2 and EX3 compared to EX1. The rate of heat production, determined as the sum of heat accumulation and release, was the same in EX1, EX2 and EX3, and it increased (P < 0.05) from 86 ± 8 during the first 15 s to 157 ± 7 J s?1 during the last 15 s of EX1. Oxygen extraction was higher during the first 60 s of EX2 and EX3 than in EX 1 and thigh oxygen uptake was elevated (P < 0.05) during the first 120 s of EX2 and throughout EX3 compared to EX1. The anaerobic energy production during the first 105 s of EX2 and 150 s of EX3 was lower (P < 0.05) than in EX1. The present study demonstrates that when intense exercise is repeated muscle heat production is not changed, but muscle aerobic energy turnover is elevated and anaerobic energy production is reduced during the first minutes of exercise. PMID:11691886

Krustrup, Peter; Gonzalez-Alonso, Jose; Quistorff, Bj?rn; Bangsbo, Jens

2001-01-01

310

Microanalysis of the reaction product in Karnovsky and Roots histochemical localization of acetylcholinesterase  

SciTech Connect

X-ray energy dispersive microanalysis of the reaction product in Karnovsky and Roots histochemical localization of acetylcholinesterase indicated the presence of sulfur, iodine, copper, and iron. The reaction was run in vitro using purified acetylcholinesterase from the electric eel to confirm our previous results on similarly treated neuromuscular junction in situ.

Tewari, J.P.; Sehgal, S.S.; Malhotra, S.K.

1982-05-01

311

Deletion of the Chloroplast-Localized Thylakoid Formation1 Gene Product in Arabidopsis Leads to  

E-print Network

Deletion of the Chloroplast-Localized Thylakoid Formation1 Gene Product in Arabidopsis Leads of membrane vesicles from the chloroplast inner envelope and subsequent fusion of vesicles within the interior stacks and ultimately for leaf development. The Arabidopsis Thf1 gene encodes an imported chloroplast

Jones, Alan M.

312

Departure from corotation of the IO plasma torus: local plasma production  

Microsoft Academic Search

The departure of the Jovian magnetosphere from rigid corotation is adequately explained by outward plasma transport at distances L> or approx. =10. The departure of 5% observed in the Io plamsa torus, however, is too large to be accounted for simply by plasma transport. We propose local plasma production to be the main factor determining the corotation lag in the

D. H. Jr. Pontius; T. W. Hill

1982-01-01

313

A PRELIMINARY STUDY ON SELENIUM CONTENT OF FORAGES AND LOCAL BY-PRODUCTS  

E-print Network

A PRELIMINARY STUDY ON SELENIUM CONTENT OF FORAGES AND LOCAL BY-PRODUCTS IN THE TADLA AREA (MOROCCO flock (Berger et al., 1983). The relationship between enzootic ovine myopathy and selenium deficiency has been highlighted in many countries (Lamand, 1966). In order to evidence selenium deficiency

Paris-Sud XI, Université de

314

Doing Cultural Work: Local Postcard Production and Place Identity in a Rural Shire  

ERIC Educational Resources Information Center

Studies of place construction in the rural studies literature have largely privileged the role of professionals over that of local lay actors. This paper contributes to redressing this imbalance through a critical case-study of lay postcard production in a rural shire. Drawing on original, qualitative research conducted in the Shire of…

Mayes, Robyn

2010-01-01

315

Resistivity and Specific Heat under Localized Anharmonic Motion in Type-I Ba8Ga16Sn30 Clathrate  

NASA Astrophysics Data System (ADS)

Anharmonic guest atom oscillation has direct connection to the thermal transport and thermoelectric behavior of type-I Ba8Ga16Sn30 clathrates. This behavior can be observed through several physical properties, with for example the heat capacity providing a measure of the overall excitation level structure. In addition the nuclear magnetic resonance (NMR) relaxation behavior provides a sensitive probe for the oscillator dynamics, as we have recently reported. Localized anharmonic excitations also influence the low-temperature resistivity, as we show in this paper. By combining heat capacity and transport measurements we address the distribution of local-oscillators in this material, as well as the shape of the confining potential for Ba ions in the cages. Analyzed along with NMR relaxation measurements for the same sample, a two phonon Raman process is used to extract information about the excitation energies, which along with a quantum computational solver we have used to address the potential structure. We also compare to the soft-potential model and other models used for this system. The results indicate that a single confining potential cannot describe the system properly, whereas a distribution of local oscillators provides a more reasonable fit to the data.

Zheng, Xiang; Rodriguez, Sergio Y.; Saribaev, Laziz; Ross, Joseph H., Jr.

2012-02-01

316

Heat pipe local cooling system applied for 145 kV transmission lines in Copenhagen  

Microsoft Academic Search

This paper reports that in connection with the planned installation of a 145 kV power transmission system in Copenhagen, crossings with the distribution piping of regional centralized heating systems were expected to give rise to numerous hot spots, and consequently measures to cope with thermal interference become necessary. Various possible countermeasures were considered, and as a result of these studies,

Z. Iwata; S. Sakuma; M. Dam-Andersen; E. Jacobsen

1992-01-01

317

Heat pipe local cooling system applied for 145 kV transmission lines in Copenhagen  

Microsoft Academic Search

In connection with the planned installation of a 145 kV power transmission system in Copenhagen, crossings with the distribution piping of regional centralized heating systems were expected to give rise to numerous hot spots, and consequently measures to cope with thermal interference became necessary. Various possible countermeasures were considered, and as a result of these studies, a new type of

Z. Iwata; S. Sakuma; M. Dam-Andersen; E. Jacobsen

1991-01-01

318

Measurement of locally heated liquid film thickness by a double-fiber optical probe  

Microsoft Academic Search

An experimental investigation of thermocapillary deformations in a film of 10% ethyl alcohol solution in water, flowing down a plate with a heater of length 6.7 mm and width 68 mm, is performed. Heating of the film results in the formation of a horizontal liquid bump at the top edge of the heater. On the heater the flow divides into vertical rivulets

D. V. Zaitsev; O. A. Kabov; A. R. Evseev

2003-01-01

319

Multitemporal Landsat data for urban heat island assessment and classification of local climate zones  

Microsoft Academic Search

The urban heat island is the most analyzed feature in urban climatology and an important application in urban remote sensing. A common approach is the application of thermal- infrared radiometers for inner urban temperature characteriza- tion, although several problems remain unsolved. Another ap- proach is the direct determination of thermal surface properties and thematic classification using multitemporal thermal imagery. In

Benjamin Bechtel

2011-01-01

320

Transient Mixed Convection In Channels Partially Heated Filled With A Porous Medium In Non-Local Thermal Equilibrium  

NASA Astrophysics Data System (ADS)

In this paper, reference is made to transient mixed convection in air in a vertical channel with porous media and the two principal flat plates at uniform temperature with adiabatic extensions downstream. The numerical analysis is carried out in transient laminar, two dimensional and in nonlocal thermal equilibrium. The physical domain consists of two parallel plates which form a channel and the adiabatic extensions downstream to the heated walls. Both plates are heated at uniform temperature. The fluid between the two plates is air. The study is carried out employing Brinkman-Forchheimer-extended Darcy model and two energy equations. The flow in the channel is assumed to be two-dimensional, laminar, incompressible. Results in terms of local Nusselt number profiles as a function of mass flow rate, adiabatic extensions length, wall temperatures and channel spacing are presented. Average Nusselt numbers are presented for different values of characteristic parameters.

Buonomo, Bernardo; Manca, Oronzio; Mesolella, Paolo; Nardini, Sergio

2010-05-01

321

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

322

Modeling the Daly Gap: The Influence of Latent Heat Production in Controlling Magma Extraction and Eruption  

NASA Astrophysics Data System (ADS)

A century-old issue in volcanology is the origin of the gap in chemical compositions observed in magmatic series on ocean islands and arcs - the "Daly Gap". If the gap forms during differentiation from a mafic parent, models that predict the dynamics of magma extraction as a function of chemical composition must simulate a process that results in volumetrically biased, bimodal compositions of erupted magmas. The probability of magma extraction is controlled by magma dynamical processes, which have a complex response to magmatic heat evolution. Heat loss from the magmatic system is far from a simple, monotonic function of time. It is modified by the crystallization sequence, chamber margin heat flux, and is buffered by latent heat production. We use chemical and thermal calculations of MELTS (Ghiorso & Sack, 1995) as input to the physical model of QUANTUM (Dufek & Bachmann, 2010) to predict crystallinity windows of most probable magma extraction. We modeled two case studies: volcanism on Tenerife, Canary Islands, and the Campanian Ignimbrite (CI) of Campi Flegrei, Italy. Both preserve a basanitic to phonolitic lineage and have comparable total alkali concentrations; however, CI has high and Tenerife has low K2O/Na2O. Modeled thermal histories of differentiation for the two sequences contrast strongly. In Tenerife, the rate of latent heat production is almost always greater than sensible heat production, with spikes in the ratio of latent to sensible heats of up to 40 associated with the appearance of Fe-Ti oxides at near 50% crystallization. This punctuated heat production must cause magma temperature change to stall or slow in time. The extended time spent at ?50% crystallinity, associated with dynamical processes that enhance melt extraction near 50% crystallinity, suggests the magma composition at this interval should be common. In Tenerife, the modeled composition coincides with that of the first peak in the bimodal frequency-composition distribution. In our model, we move the extracted liquid to a shallower chamber (1.5 kbar as inferred for Tenerife phonolite) and resume crystallization. At the optimal magma extraction window of ?50% crystallinity, the composition matches well with the observed composition of the second peak of the bimodal distribution. In contrast, CI does not show an early spike in latent heat production, but a late (?900°C) pseudo-invariant point where latent heat production spikes. This spike is very near the 50% crystallinity window, again enhancing the probability of magma extraction. The model liquid composition at this crystallinity matches the observed trachyte composition. In both systems, phase chemistry supports a two-chamber evolution, one deep and the second shallow, corresponding to two primary melt extraction events. Realistically incorporating chemical, thermal and physical processes in magma chamber models provides composition-volume estimates of extracted magma that coincide with observed bimodal composition-volume relations. The strong variability in latent heat production is an important control, and its characterization is central to physical models of magma chamber evolution.

Nelson, B. K.; Ghiorso, M. S.; Bachmann, O.; Dufek, J.

2011-12-01

323

Heat stress impairs the nutritional metabolism and reduces the productivity of egg-laying ducks.  

PubMed

This research was conducted to determine the effect of heat stress on the nutritional metabolism and productivity of egg-laying shelducks. Healthy shelducks (n=120) in the early laying stage (uniform body weights and normal feed intakes) were randomly assigned to two identical climate chambers and exposed to constant high temperature (34°C) or control temperature (23°C) for 28d. The heat-exposed ducks had reduced feed intakes and laying rates (P<0.05), increased frequency of panting and spreading wings and dull featheration; egg weight, eggshell thickness and strength, and Haugh unit also decreased and malondialdehyde (MDA) content of egg yolk increased (P<0.05). Compared with the control ducks, the plasma concentrations of HCO3(-), phosphorus, glucose, thyroxine and activities of glutamic-pyruvic transaminase and glutamic oxaloacetic transaminase were decreased, while there were increased concentrations of corticosterone (P<0.05). The content of MDA and lactate in plasma and liver was greater in heat-exposed than in control ducks, but superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), total antioxidant enzymes (T-AOC) activities and glutathione (GSH) contents were less. The expression of HSP70 gene expression in the liver was increased in heat-stressed ducks. The relative weight of oviduct, number of large ovarian follicles, length of the oviduct all decreased (P<0.05) in heat-treated ducks, as did expression of carbonic anhydrase and calcium binding protein genes in the shell gland as a result of heat stress. In summary, heat stress decreased the productivity of ducks, which related to reduced feed intake, protein synthesis, endocrine dysfunction, less antioxidant capacity, and derangement of calcium and phosphorous balance. PMID:24491646

Ma, Xianyong; Lin, Yingcai; Zhang, Hanxing; Chen, Wei; Wang, Shang; Ruan, Dong; Jiang, Zongyong

2014-03-01

324

Effect of rib angle on local heat/mass transfer distribution in a two-pass rib-roughened channel  

NASA Technical Reports Server (NTRS)

The naphthalene sublimation technique is used to investigate the heat transfer characteristics of turbulent air flow in a two-pass channel. A test section that resembles the internal cooling passages of gas turbine airfoils is employed. The local Sherwood numbers on the ribbed walls were found to be 1.5-6.5 times those for a fully developed flow in a smooth square duct. Depending on the rib angle-of-attack and the Reynolds number, the average ribbed-wall Sherwood numbers were 2.5-3.5 times higher than the fully developed values.

Chandra, P. R.; Han, J. C.; Lau, S. C.

1987-01-01

325

An assessment of solar hot water heating in the Washington, D.C. area - Implications for local utilities  

NASA Astrophysics Data System (ADS)

A survey of residential solar hot water heating in the Washington, D.C. area is presented with estimates of the total solar energy contribution per year. These estimates are examined in relation to a local utility's peak-load curves to determine the impact of a substantial increase in solar domestic hot water use over the next 20 yr in the area of utility management. The results indicate that a 10% market penetration of solar water heaters would have no detrimental effect on the utility's peak-load profile and could save several million dollars in new plant construction costs.

Stuart, M. W.

1980-04-01

326

Local heat transfer distribution in a two-pass trapezoidal channel with a 180 [degree] turn via transient liquid crystal technique  

E-print Network

encapsulated thermochromic liquid crystals, are conducted to obtain the local heat transfer coefficient distributions for various rates of air flow through the channel, corresponding to Reynolds numbers ranging between 12000 and 88000. The turn induces...

Endley, Saurabh

2012-06-07

327

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

328

Heat of Combustion of the Product Formed by the Reaction of Acetylene, Ethylene, and Diborane  

NASA Technical Reports Server (NTRS)

The net heat of combustion of the product formed by the reaction of diborane with a mixture of acetylene and ethylene was found to be 20,440 +/- 150 Btu per pound for the reaction of liquid fuel to gaseous carbon dioxide, gaseous water, and solid boric oxide. The measurements were made in a Parr oxygen-bomb calorimeter, and the combustion was believed to be 98 percent complete. The estimated net-heat of combustion for complete combustion would therefore be 20,850 +/- 150 Btu per pound.

Tannenbaum, Stanley

1957-01-01

329

Optimization of a Mu2e production solenoid heat and radiation shield using MARS15  

SciTech Connect

A Monte-Carlo study of several Mu2e Production Solenoid (PS) absorber (heat shield) versions using the MARS15 code has been performed. Optimizations for material as well as cost (amount of tungsten) have been carried out. Studied are such quantities as the number of displacements per atom (DPA) in the helium-cooled solenoid superconducting coils, power density and dynamic heat load in various parts of the PS and its surrounding structures. Prompt dose, residual dose, secondary particle flux are also simulated in the PS structures and the experimental hall. A preliminary choice of the PS absorber design is made on the ground of these studies.

Pronskikh, V.S.; Mokhov, N.V.; /Fermilab

2011-02-01

330

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

331

Effects of supplemental fats on intake, production, and heat stress in lactating Holstein cows in summer  

E-print Network

temperature cause a rise in body temperature (35). A rise in body temperature is a consequence of the failure of other cooling methods to maintain homeo- thermy. Thus, the animals are under heat stress. The increases in body temperature and respiration... of the animal is widely accepted as a major negative influence on milk production (9). According to the NRC (35), lactating cows under heat stress begin to show a decline in feed intake at environmental tempera- tures of 25 to 27 C, with intakes declining...

Saunders, Richard Glynn

2012-06-07

332

A local heat transfer analysis of lava cooling in the atmosphere: application to thermal diffusion-dominated lava flows  

NASA Astrophysics Data System (ADS)

The local cooling process of thermal diffusion-dominated lava flows in the atmosphere was studied by a transient, one-dimensional heat transfer model taking into account the most relevant processes governing its behavior. Thermal diffusion-dominated lava flows include any type of flow in which the conductive-diffusive contribution in the energy equation largely overcomes the convective terms. This type of condition is supposed to be satisfied, during more or less extended periods of time, for a wide range of lava flows characterized by very low flow-rates, such as slabby and toothpaste pahoehoe, spongy pahoehoe, flow at the transition pahoehoe-aa, and flows from ephemeral vents. The analysis can be useful for the understanding of the effect of crust formation on the thermal insulation of the lava interior and, if integrated with adequate flow models, for the explanation of local features and morphologies of lava flows. The study is particularly aimed at a better knowledge of the complex non-linear heat transfer mechanisms that control lava cooling in the atmosphere and at the estimation of the most important parameters affecting the global heat transfer coefficient during the solidification process. The three fundamental heat transfer mechanisms with the atmosphere, that is radiation, natural convection, and forced convection by the wind, were modeled, whereas conduction and heat generation due to crystallization were considered within the lava. The magma was represented as a vesiculated binary melt with a given liquidus and solidus temperature and with the possible presence of a eutectic. The effects of different morphological features of the surface were investigated through a simplified description of their geometry. Model results allow both study of the formation in time of the crust and the thermal mushy layer underlying it, and a description of the behavior of the temperature distribution inside the lava as well as radiative and convective fluxes to the atmosphere. The analysis, performed by using parameters typical of Etnean lavas, particularly focuses on the non-intuitive relations between superficial cooling effects and inner temperature distribution as a function of the major variables involved in the cooling process. Results integrate recent modelings and measurements of the cooling process of Hawaiian pahoehoe flow lobes by Hon et al. (1994) and Keszthelyi and Denlinger (1996) and highlight the critical role played by surface morphology, lava thermal properties, and crystallization dynamics. Furthermore, the reported description of the various heat fluxes between lava and atmosphere can be extended to any other type of lava flows in which atmospheric cooling is involved.

Neri, Augusto

1998-05-01

333

Current localization, non-uniform heating, and failures of ZnO varistors  

Microsoft Academic Search

Metal oxide varistors have highly nonlinear electrical characteristics and are widely used as devices for over-voltage protection. Varistor applications range from the use of small varistors to protect delicate electronic components to the use of much larger varistors for the protection of electrical-power-distribution systems. Non-uniform heating of ZnO varistors by electrical pulses occurs on three different spatial scales: (1) microscopic

Bartkowiak

1997-01-01

334

Oil space heating pollutes the air more than the local fossil-fueled electric company  

Microsoft Academic Search

This study was performed in an area of Long Island, New York which is nearly isolated from other populated regions except from due west, it has a high population density, it has fossil-fueled electric power plants with no stack-gas scrubbers, the principal space-heating fuel is sulfur-bearing oil for both residential and commercial electric company customers, and it contains a very

A. J. Jr ONeal; E. Chandler; Dew H. H

1984-01-01

335

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

336

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

337

Local energy balance, specific heats and the Oberbeck–Boussinesq approximation  

Microsoft Academic Search

A thermodynamic argument is proposed in order to discuss the most appropriate form of the local energy balance equation within the Oberbeck–Boussinesq approximation. The study is devoted to establish the correct thermodynamic property to be used in order to express the relationship between the change of internal energy and the temperature change. It is noted that, if the fluid is

A. Barletta

2009-01-01

338

Localized Joule heating produced by ion current focusing through micron-size holes  

Microsoft Academic Search

We provide an experimental demonstration that the focusing of ionic currents in a micron size hole connecting two chambers can produce local temperature increases of up to 100 °C with gradients as large as 1°K mum-1. We find a good agreement between the measured temperature profiles and a finite elements-based numerical calculation. We show how the thermal gradients can be

V. Viasnoff; U. Bockelmann; A. Meller; H. Isambert; L. Laufer; Y. Tsori

2010-01-01

339

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

340

Econometric model of the joint production and consumption of residential space heat  

SciTech Connect

This study models the production and comsumption of residential space heat, a nonmarket good. Production reflects capital investment decisions of households; consumption reflects final demand decisions given the existing capital stock. In the model, the production relationship is represented by a translog cost equation and an anergy factor share equation. Consumption is represented by a log-linear demand equation. This system of three equations - cost, fuel share, and final demand - is estimated simultaneously. Results are presented for two cross-sections of households surveyed in 1973 and 1981. Estimates of own-price and cross-price elasticities of factor demand are of the correct sign, and less than one in magnitude. The price elasticity of final demand is about -0.4; the income elasticity of final demand is less than 0.1. Short-run and long-run elasticities of demand for energy are about -0.3 and -0.6, respectively. These results suggest that price-induced decreases in the use of energy for space heat are attributable equally to changes in final demand and to energy conservation, the substitution of capital for energy in the production of space heat. The model is used to simulate the behavior of poor and nonpoor households during a period of rising energy prices. This simulation illustrates the greater impact of rising prices on poor households.

Klein, Y.L.

1985-12-01

341

Econometric model of the joint production and consumption of residential space heat  

SciTech Connect

This study models the production and consumption of residential space heat, a nonmarket good. Production reflects capital investment decisions of households; consumption reflects final demand decisions given the existing capital stock. In the model, the production relationship is represented by a translog cost equation and an energy factor share equation. Consumption is represented by a log-linear demand equation. This system of three equations - cost, fuel share, and final demand - is estimated simultaneously. Results are presented for two cross-sections of households, surveyed in 1973 and 1981. Estimates of own price and cross-price elasticities of factor demand are of the correct sign, and less than one in magnitude. The price elasticity of final demand is about -0.4; the income elasticity of final demand is less than 0.1. Short-run and long-run elasticities of demand for energy are about -0.3 and -0.6. These results suggest that price-induced decreases in the use of energy for space heat are attributable equally to changes in final demand and to energy conservation, the substitution of capital for energy in the production of space heat. The estimated model is used to simulate the behavior of poor and nonpoor households during a period of rising energy prices. This simulation illustrates the greater impact of rising prices on poor households.

Klein, Y.L.

1985-01-01

342

PCR-SSCP-based reconstruction of the original fungal flora of heat-processed meat products.  

PubMed

Food processing of spoiled meat is prohibited by law, since it is a deception and does not comply with food safety aspects. In general, spoilage of meat is mostly caused by bacteria. However, a high contamination level of fungi could be also found in some meat or meat products with certain preserving conditions. In case that unhygienic meat is used to produce heat processed products, the microorganisms will be deactivated by heat, so that they cannot be detected by a standard cultivation method. Therefore, this study aimed to develop and apply a molecular biological method--polymerase chain reaction and single strand conformation polymorphism (PCR-SSCP)--to reconstruct the original fungal flora of heat processed meat. Twenty primer pairs were tested for their specificity for fungal DNA. Since none of them fully complied with all study criteria (such as high specificity and sensitivity for fungal DNA; suitability of the products for PCR-SSCP) in the matrix "meat", we designed a new reverse primer, ITS5.8R. The primer pair ITS1/ITS5.8R amplified DNA from all tested fungal species, but not DNA from meat-producing animals or from ingredients of plant origin (spices). For the final test, 32 DNA bands in acrylamide gel from 15 meat products and 1 soy sauce were sequenced-all originating from fungal species, which were, in other studies, reported to contaminate meat e.g. Alternaria alternata, Aureobasidium pullulans, Candida rugosa, C. tropicalis, C. zeylanoides, Eurotium amstelodami and Pichia membranifaciens, and/or spices such as Botrytis aclada, Guignardia mangiferae, Itersonilia perplexans, Lasiodiplodia theobromae, Lewia infectoria, Neofusicoccum parvum and Pleospora herbarum. This confirms the suitability of PCR-SSCP to specifically detect fungal DNA in heat processed meat products, and thus provides an overview of fungal species contaminating raw material such as meat and spices. PMID:23361099

Dorn-In, Samart; Hölzel, Christina S; Janke, Tobias; Schwaiger, Karin; Balsliemke, Joachim; Bauer, Johann

2013-03-01

343

Radioelements and heat production of an exposed Archaean crustal cross-section, Dharwar craton, south India  

NASA Astrophysics Data System (ADS)

The Dharwar craton (DC) in south India exposes a tilted ˜30-km-thick crustal section equivalent to upper, middle and lower Archaean continental crust. The DC is composed of poly-magmatic-metamorphic terrains such as the Western Dharwar Craton (WDC) and Eastern Dharwar Craton (EDC) whose contact is marked by the Closepet Granite batholith (CG). In-situ gamma-ray spectrometric analysis has been carried out to measure K, U and Th abundance at 1023 sites covering all major rock formations of the DC. The data show that the greenschist and amphibolite facies tonalite-trondhjemite-granodioritic (TTG) gneisses of the WDC are poorer in radioelements compared to granodioritic gneisses of the EDC. Similarly, the WDC granites of the amphibolite facies region have lower abundance indicating their derivation from a depleted lower crust, which had suffered an earlier crustal differentiation. The elemental data on the gneisses in the WDC and EDC do not show a difference between the greenschist and amphibolite facies, but there is a marked depletion in the granulite facies. The depletion reaches a maximum in the high- P granulites in the southernmost part of the DC. The elongate CG is an I-type, calc-alkaline, metaluminous granite, which exposes a ˜12-km-thick batholith, where K is remarkably uniform but U and Th show several fold increase with decreasing crustal levels. Heat production was calculated from the radioelemental data. For estimating the radiogenic heat contribution of crust to heat flow, we arrive at a present-day crustal configuration comprising four northerly dipping metamorphic facies layers: greenschist, amphibolite, metasomatized granulite and depleted granulite. Gross heat production of each layer is computed from heat production of constituent rocks and their abundance. The crustal contribution is found to decrease, from greenschist to granulite facies regions, from 23 to 18 mW m -2 in the WDC, 27 to 7 mW m -2 in the EDC. Surface heat flow and the crustal contribution models indicate that mantle heat flow of the WDC is lower (7-10 mW m -2) compared to the EDC (17-24 mW m -2) in the greenschist and amphibolite facies regions. High mantle heat flow of 29 mW m -2 beneath the depleted granulite facies region of the EDC appears anomalous in the Dharwar craton.

Kumar, P. Senthil; Reddy, G. K.

2004-08-01

344

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

345

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

346

Analysis of Vertical Turbulent Heat Flux Limit in Stable Conditions with a Local Equilibrium, Turbulence Closure Model  

NASA Astrophysics Data System (ADS)

Assuming that the vertical turbulent heat flux vanishes at extremely stable conditions, one should expect its maximal absolute value to occur somewhere at moderate stability, between a neutral and extremely stable equilibrium. Consequently, in some situations duality of solutions may be encountered (e.g. two different values of temperature difference associated with the same values of heat flux and wind speed). A quantitative analysis of this feature with a local equilibrium Reynolds-stress model is presented. The fixed-wind / fixed-shear maximum has been identified both in the bulk and in single-point flux-gradient relationships (that is, in the vertical temperature gradient and wind-shear parameter domain). The value of the Richardson number corresponding to this maximum is derived from the model equations. To study the possible feedback in strongly stable conditions, weak and intense cooling scenarios have been simulated with a one-dimensional numerical, high-resolution atmospheric boundary-layer model. Despite the rapid cooling, flow decoupling at the surface has not been observed; instead, a stability-limited heat flux is maintained, with a gradual increase of the Richardson number towards the top of the turbulent layer, with some signs of oscillatory behaviour at intermediate heights. Vertical changes of wind shear and the Brunt-Väisälä frequency display a remarkably non-monotonic character, with some signs of a gradually developing instability.

?obocki, Lech

2013-09-01

347

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

348

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

349

Responses to heat stress in commercial and local broiler stocks. 2. Developmental stability of bilateral traits.  

PubMed

1. Developmental stability of bilaterally symmetrical traits was measured in two fast (G1 and G2) and one slower growing (G3) broiler stocks when conditioned (chicks exposed to 36 degrees C for 24 h at 5 d of age) or food restricted (food withdrawn 2 h before the hot period and chicks fed between 17.00 and 08.00 h) during heat stress administered daily from 28 to 49 d of age. 2. Length of face, length, width and weight of shanks, weights of P. major and P. minor muscles, and weights of lung and caeca were chosen as bilateral traits representative of skeletal, muscle, respiratory and digestive systems. 3. Development of skeletal bilateral traits was affected primarily by genotype and sex. The heart:lung ratio decreased with conditioning in stocks G1 and G2 at 21 d. Face length, shank length and shank weight exhibited antisymmetry, whereas shank width and weights of P. minor, lung and caeca exhibited fluctuating asymmetry and antisymmetry. For P. major weight, there was directional asymmetry. 4. In general, relative asymmetry of skeletal traits was lower than for traits associated with muscle and with respiratory and digestive systems. Relative asymmetry of P. major weight was lower in conditioned and G3 broilers than in their respective counterparts. 5. If relative asymmetry is a valid indicator, item heat stress may be less in slower growing and conditioned broilers. PMID:11421322

Yalçin, S; Ozkan, S; Türkmut, L; Siegel, P B

2001-05-01

350

The reduction of heat production in exercising pigeons after L-carnitine supplementation.  

PubMed

Four groups (CS,CR,PS,PR) of nine trained male racing pigeons were deprived of feed for 1 d and then subjected to a respiration chamber test in order to study the effect of oral 1-carnitine supplementation on the energy metabolism during flight. One week before, groups CS and CR were orally supplemented with 90 mg of 1-carnitine daily, whereas PS and PR were given a placebo. Groups CS and PS underwent flight simulation by electrostimulation of the breast muscles. Flight simulation increased heat production, kept respiratory quotient from decreasing, decreased thyroxine levels, and increased weight loss. L-Carnitine decreased the rise in heat production during electrostimulation but did not influence respiratory quotient, weight loss, or thyroid hormones. L-Carnitine supplementation in pigeons improves fatty acid combustion efficiency during heavy exercise. PMID:9565242

Janssens, G P; Buyse, J; Seynaeve, M; Decuypere, E; De Wilde, R

1998-04-01

351

The Effect of Calcium Depletion upon the Tension-Independent Component of Cardiac Heat Production  

PubMed Central

Rabbit papillary muscle has been exposed to calcium concentrations ranging from 2.5 mM to zero. Its mechanical and electrical activity has been monitored and its heat production measured using a myothermic technique. Calcium depletion decreased the magnitude of the tension-independent heat per contraction from a mean of 0.45 mcal/g muscle to 0.31 mcal/g muscle at room temperature (18° to 22°C). Calcium-chelating agents did not abolish action potential conduction under the experimental conditions used but they further reduced the magnitude of the tension-independent heat. Raising the temperature from room level to 32°C decreased the tension-independent heat from a mean of 0.52 to a mean of 0.24 mcal/g muscle. Calcium depletion at 32°C further decreased this heat and it was calculated that the energy now liberated in activating the muscle was about 2% of the total energy normally liberated in the working heart. The results are interpreted in terms of current biochemical and myothermic data. PMID:4970572

Gibbs, C. L.; Vaughan, P.

1968-01-01

352

Enhancement of anaerobic biohydrogen/methane production from cellulose using heat-treated activated sludge.  

PubMed

Anaerobic digestion is an effective technology to convert cellulosic wastes to methane and hydrogen. Heat-treatment is a well known method to inhibit hydrogen-consuming bacteria in using anaerobic mixed cultures for seeding. This study aims to investigate the effects of heat-treatment temperature and time on activated sludge for fermentative hydrogen production from alpha-cellulose by response surface methodology. Hydrogen and methane production was evaluated based on the production rate and yield (the ability of converting cellulose into hydrogen and methane) with heat-treated sludge as the seed at various temperatures (60-97 degrees C) and times (20-60 min). Batch experiments were conducted at 55 degrees C and initial pH of 8.0. The results indicate that hydrogen and methane production yields peaked at 4.3 mmol H2/g cellulose and 11.6 mmol CH4/g cellulose using the seed activated sludge that was thermally treated at 60 degrees C for 40 min. These parameter values are higher than those of no-treatment seed (HY 3.6 mmol H2/g cellulose and MY 10.4 mmol CH4/g cellulose). The maximum hydrogen production rate of 26.0 mmol H2/L/d and methane production rate of 23.2 mmol CH4/L/d were obtained for the seed activated sludge that was thermally treated at 70 degrees C for 50 min and 60 degrees C for 40 min, respectively. PMID:21902022

Lay, C H; Chang, F Y; Chu, C Y; Chen, C C; Chi, Y C; Hsieh, T T; Huang, H H; Lin, C Y

2011-01-01

353

Photon and Particle Emission, Heat Production and Surface Transformation in Ni-H System  

Microsoft Academic Search

The results obtained in several experiments on Ni-H system are presented here. Photon emission during the preliminary phases of activation and 1H isotope absorption are shown; their correlation with the kind of surfaces (Ni and its alloys) and with neutron and other particle emission in the excitation progress and in large heat production is also presented. Finally, the SEM-EDAX analysis

E. Campari; G. Fasano; S. Focardi; G. Lorusso; V. Gabbani; V. Montalbano; F. Piantelli; C. Stanghini; S. Veronesi

2006-01-01

354

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

355

Localized production of human E-cadherin-derived first repeat in Escherichia coli  

Microsoft Academic Search

E-cadherin is a cell surface adhesion molecule that is expressed in both epithelial and endothelial tissues. In this study, an improved method for the simple production of the human E-cadherin-derived first repeat E-CAD1 was developed by exporting it into the periplasmic space of Escherichia coli. Localization of the recombinant protein into the periplasm allowed the isolation of E-CAD1 without cell

Irwan T Makagiansar; Atsutoshi Ikesue; Phuong Duc Nguyen; Jeffrey L Urbauer; Ramona J Bieber Urbauer; Teruna J Siahaan

2002-01-01

356

Targeting the Local: Policing Clandestine Methamphetamine Production in a Rural US Community  

Microsoft Academic Search

: In the United States, state-based efforts to curtail the spread of methamphetamine (“meth”) have targeted domestic producers through heightened regulation of precursor chemicals used in the clandestine meth-production process. This article examines the impact of these efforts on the exercise of police power in a rural community affected by methamphetamine. As the author shows, the targeting of local meth

William Garriott

2010-01-01

357

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

358

Genome-wide analysis of the Populus Hsp90 gene family reveals differential expression patterns, localization, and heat stress responses  

PubMed Central

Background Members of the heat shock protein 90 (Hsp90) class of proteins are evolutionarily conserved molecular chaperones. They are involved in protein folding, assembly, stabilization, activation, and degradation in many normal cellular processes and under stress conditions. Unlike many other well-characterized molecular chaperones, Hsp90s play key roles in signal transduction, cell-cycle control, genomic silencing, and protein trafficking. However, no systematic analysis of genome organization, gene structure, and expression compendium has been performed in the Populus model tree genus to date. Results We performed a comprehensive analysis of the Populus Hsp90 gene family and identified 10 Populus Hsp90 genes, which were phylogenetically clustered into two major groups. Gene structure and motif composition are relatively conserved in each group. In Populus trichocarpa, we identified three paralogous pairs, among which the PtHsp90-5a/PtHsp90-5b paralogous pair might be created by duplication of a genome segment. Subcellular localization analysis shows that PtHsp90 members are localized in different subcellular compartments. PtHsp90-3 is localized both in the nucleus and in the cytoplasm, PtHsp90-5a and PtHsp90-5b are in chloroplasts, and PtHsp90-7 is in the endoplasmic reticulum (ER). Furthermore, microarray and semi-quantitative real-time RT-PCR analyses show that a number of Populus Hsp90 genes are differentially expressed upon exposure to various stresses. Conclusions The gene structure and motif composition of PtHsp90s are highly conserved among group members, suggesting that members of the same group may also have conserved functions. Microarray and RT-PCR analyses show that most PtHsp90s were induced by various stresses, including heat stress. Collectively, these observations lay the foundation for future efforts to unravel the biological roles of PtHsp90 genes. PMID:23915275

2013-01-01

359

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

360

Supramaximal heat production induced by aminophylline in temperature-acclimated rats  

NASA Astrophysics Data System (ADS)

Previous studies have shown that aminophylline, a phosphodiesterase inhibitor (thereby increasing intracellular cyclic AMP concentration) elicits supramaximal heat production and improves cold tolerance in rats acclimated to 22°C. To test whether aminophylline-stimulated supramaximal thermogenesis is independent of both the thermogenic capacity (i.e. aerobic fitness) and the mode of thermogenesis (shivering vs. non-shivering), rats (adult male Sprague-Dawley, approximately 400 g) of two different ages (4 11 month and 9 17 month, n=12 for each) were acclimated to 5, 15, and 25°C in succession and their thermogenic responses to aminophylline subsequently assessed. Aminophylline elicited supramaximal thermogenesis and improved cold tolerance regardless of age or acclimating temperatures. Further, the absolute net increase in heat production stimulated by aminophylline was also similar for all acclimating temperatures. After acclimating to 15°C, a single injection of aminophylline in the older rats elicited thermogenesis greater than that of the controls acclimated to 5°C; in the younger rats, aminophylline duplicated 46% of the increase in thermogenesis observed after acclimating to 5°C. These results indicated that the aminophylline-stimulated extra heat production is independent of both the thermogenic capacity and the mode of thermogenesis. It is possible that an enhanced substrate mobilization consequent to increased intracellular cyclic AMP concentration by aminophylline underlies the common mechanism via which supramaximal thermogenesis is elicited in temperature-acclimated rats.

Wang, L. C. H.

1985-03-01

361

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

362

Localized Joule heating produced by ion current focusing through micron-size holes  

NASA Astrophysics Data System (ADS)

We provide an experimental demonstration that the focusing of ionic currents in a micron size hole connecting two chambers can produce local temperature increases of up to 100 °C with gradients as large as 1°K ?m-1. We find a good agreement between the measured temperature profiles and a finite elements-based numerical calculation. We show how the thermal gradients can be used to measure the full melting profile of DNA duplexes within a region of 40 ?m. The possibility to produce even larger gradients using submicron pores is discussed.

Viasnoff, V.; Bockelmann, U.; Meller, A.; Isambert, H.; Laufer, L.; Tsori, Y.

2010-04-01

363

Localized Joule heating produced by ion current focusing through micron-size holes  

E-print Network

We provide an experimental demonstration that the focusing of ionic currents in a micron size hole connecting two chambers can produce local temperature increases of up to $100^\\circ$ C with gradients as large as $1^\\circ$ K$\\mu m^{-1}$. We find a good agreement between the measured temperature profiles and a finite elements-based numerical calculation. We show how the thermal gradients can be used to measure the full melting profile of DNA duplexes within a region of 40 $\\mu$m. The possibility to produce even larger gradients using sub-micron pores is discussed.

V. Viasnoff; U. Bockelmann; A. Meller; H. Isambert; L. Laufer; Y. Tsori

2010-04-27

364

Electroslag welding of the circular joints of large apparatus with localized normalizing with gas heating  

Microsoft Academic Search

With a width of heavy rolled plate of about 2 m the primary volume of welding work is the welding of circular joints. Multipass automatic welding under flux of metal of significant thickness has a low rate of productivity and is accompanied by the formation of various defects such as slag inclusions, poor penetration, and cracks in the weld metal.

A. M. Makara; I. V. Novikov; A. S. Iskra; A. E. Erinov; V. A. Sokora; I. N. Medrish; I. K. Drankovskii; V. A. Rumyantsev

1975-01-01

365

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

366

High frequency core localized modes in neutral beam heated plasmas on TFTR  

SciTech Connect

A band of high frequency modes in the range 50--150 kHz with intermediate toroidal mode numbers 4 < n < 10 are commonly observed in the core of supershot plasmas on TFTR. Two distinct varieties of MHD modes are identified corresponding to a flute-like mode predominantly appearing around the q = 1 surface and an outward ballooning mode for q > 1. The flute-like modes have nearly equal amplitude on the high field and low field side of the magnetic axis and are mostly observed in moderate performance supershot plasmas with {tau}{sub E} < 2{tau}{sub L} while the ballooning-like modes have enhanced amplitude on the low field side of the magnetic axis and tend to appear in higher performance supershot plasmas with {tau}{sub E} > 2{tau}{sub L}, where {tau}{sub L} is the equivalent L-mode confinement time. The modes propagate in the ion diamagnetic drift direction and are highly localized with radial widths {Delta}r {approximately} 5--10 cm, fluctuation levels {tilde n}/n, {tilde T}{sub e}/T{sub e} < 0.01, and radial displacements {zeta}{sub r} {approximately} 0.1 cm. Unlike the toroidally localized high-n activity observed just prior to major and minor disruptions on TFTR, these modes are typically much weaker, more benign, and may be indicative of kinetic ballooning modes destabilized by resonant circulating neutral beam ions.

Nazikian, R.; Chang, Z.; Fredrickson, E.D. [and others

1995-11-01

367

Dietary fat affects heat production and other variables of equine performance, under hot and humid conditions.  

PubMed

Does dietary fat supplementation during conditioning improve athletic performance, especially in the heat? Fat adaptation has been used to increase energy density, decrease bowel bulk and faecal output and reduce health risks associated with hydrolysable carbohydrate overload. It may also reduce spontaneous activity and reactivity (excitability), increase fatty acid oxidation, reduce CO2 production and associated acidosis, enhance metabolic regulation of glycolysis, improve both aerobic and anaerobic performance and substantially reduce heat production. A thermochemical analysis of ATP generation showed the least heat release during the direct oxidation of long chain fatty acids, which have a 3% advantage over glucose and 20 to 30% over short chain fatty acids and amino acids. Indirect oxidation via storage as triglyceride increased heat loss during ATP generation by 3% for stearic acid, 65% for glucose and 174% for acetic acid. Meal feeding and nutrient storage, therefore, accentuates the advantage of dietary fat. A calorimetric model was based on initial estimates of net energy for competitive work (10.76 MJ for the Endurance Test of an Olympic level 3-day-event), other work (14.4 MJ/day) and maintenance (36 MJ), then applied estimates of efficiencies to derive associated heat productions for the utilisation of 3 diets, Diet A: hay (100), Diet B: hay and oats (50:50) and Diet C: hay, oats and vegetable oil (45:45:10), the difference between the last 2 diets representing fat adaptation. During a 90.5 min speed and stamina test, heat production was estimated as 37, 35.4 and 34.6 MJ for the 3 diets, respectively, an advantage 0.8 MJ less heat load for the fat adapted horse, which would reduce water needed for evaporation by 0.33 kg and reduce body temperature increase by about 0.07 degree C. Total estimated daily heat production was 105, 93 and 88 MJ for the 3 diets, respectively, suggesting a 5 MJ advantage for the fat adapted horse (Diet C vs. Diet B). Estimated intake energy was 348, 269 and 239 MJ for the 3 diets, respectively, and corresponding daily intakes as fed were 22.2, 16.6 and 12.9 kg, an advantage of 3.7 kg for the fat adapted horse. Water requirement was estimated to decrease by about 6 kg/day in the fat adapted horse: 4 kg less faecal water output and 2 kg less water for evaporation. This model indicated that the fat supplemented diet reduced daily heat load by 5%, feed intake by 22%, faecal output (and bowel ballast) by 31% and water requirement by 12%. The advantage of fat supplementation over hay and oats was in general about half that gained by hay and oats over hay alone. PMID:8894547

Kronfeld, D S

1996-07-01

368

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

369

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

370

The Role of Crustal Radiogenic Heat Production in the Stability of Hadean, Archean and Proterozoic Lithospheres  

NASA Astrophysics Data System (ADS)

Earth has had at least two major transitions in preservation of continental crust on a global scale. The first transition was at about 4 Ga from which we have the oldest remaining fragments of continental crust, such as the Acasta gneisses from the Archean Slave province, Canada. No rocks have been found from the first 500 million years of Earth history, but rocks older than 3.5 Ga have been found from all of the continents. Detrital zircon grains have been dated with ages ranging from about 3.5 to 4.4 Ga, and these mineral grains give evidence for Hadean continental crust of greater age than is preserved today, and evidence for very early oceans. The second transition was between about 2.8 and 2.3 Ga and was a transition from continental crust characteristic of older Archean terrains to crust characteristic of Proterozoic and younger terrains. The Earth has cooled significantly since its formation, both in terms of secular cooling associated with its heat of formation and in terms of decay of its radiogenic heat sources. This contribution examines possible relationships among the cooling of the Earth and the transitions in generation of continental crust. Geochemical studies of Archean upper crust show that this crust is statistically depleted in the main heat producing elements, U, Th, and K, with respect to younger crust, and this observation is quantitatively supported by heat flow data. Such depletion results in a cooler average geotherm for Archean lithosphere relative to the average geotherm for younger lithosphere. Assuming that the heat producing elements are immobile in continental lithosphere, geotherms have been back calculated to 4.5 Ga. Lithospheric strength curves have been calculated for each of these geotherms. These models show that before about 4.0 Ga, all continental geotherms resulted in strength curves so weak that no continental lithosphere resisted recycling. Between about 4.0 and 2.5 Ga, only lithosphere with cooler (low heat production) geotherms had sufficient strength to resist recycling. After 2.5 Ga, the crustal heat production was no longer a significant factor in raising the geotherm to reduce significantly lithospheric strength, and continental lithosphere has not been selectively preserved.

Morgan, P.

2006-12-01

371

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

372

Volatile production during preignition coal heating. Quarterly progress report, April 1981 - June 1981  

SciTech Connect

The goal of this program is to determine the characteristic pyrolysis behavior of representative coals under laser heating. The use of a CO/sub 2/ laser enables a controllable heating rate to be given to the coal particles as they pass through the laser beam. The development of such a laser heating diagnostic should prove to be an extremely valuable tool for generation of a data base necessary for the future design of coal burning facilities. The experimental configuration is illustrated. A dilute coal/gas stream, surrounded aby an inert shield flow is passed through a laser beam from an Avco HPL CO/sub 2/ laser. Under a prescribed flux density, and thus heating rate, the particle pyrolyse. The gaseous products are sampled and subsequently analyzed (primarily by gas chromatography) for carbon conversion. Particle temperature is to be monitored by a two-color pyrometer and particle velocity by laser Doppler velocimeter, by which means, evolution of the pyrolysis process can be determined.

Not Available

1981-07-01

373

Local Heating and Current Drive using the Fundamental O-mode EC wave on JT-60U  

NASA Astrophysics Data System (ADS)

In JT-60U, a 3 MW-level ECRF system using 3 gyrotrons was completed in March 2000. The frequency of 110 GHz was selected to launch a fundamental O-mode from the low field side. The toroidal injection angle is fixed about 15^circ to drive plasma current and poloidal injection angle can be steered using a mirror for deposition control. Up to now, the power of ~1.5 MW × 3 second ( ~2.2 MW at gyrotrons) was successfully injected to study the local electron heating and current drive. The mode purity can be controlled by rotatable grooved mirrors that generate adequate elliptical polarization. The correlation between the O-mode purity and the increase of electron temperature was clearly obtained at n_e0>0.8×10^19m-3, while weak dependence of electron heating on mode purity was observed at low density ( ~0.3 ×10^19m-3) due to the Doppler effect of fundamental X-mode absorption with toroidal oblique angle. A strongly peaked Te profile with T_e0>10 keV at n_e0 ~1×10^19m-3 was obtained for 1 s with the injected power of ~1.5MW when the O-mode purity is adjusted more than 80%. Impact on sawtooth activity, both suppression and enhancement depending on ECW deposition and direction of EC driven current to the plasma current, was observed. In view of local current drive, changes in MSE signals were observed.

Kajiwara, Ken; Isayama, Akihiko; Suzuki, Takahiro; Ide, Shunsuke; Kasugai, Atsusi; Takahashi, Koji; Ikeda, Yoshitaka; Fujii, Tsuneyuki

2000-10-01

374

Calorimetric Determinations of the Heat and Products of Detonation for Explosives: October 1961 to April 1982  

NASA Astrophysics Data System (ADS)

This report is a compilation of heat-of-detonation and product-composition data obtained at Lawrence Livermore National Laboratory during the last 21 years. In each determination, a 25-g high-explosive charge was detonated in a bomb calorimeter; a complete calorimetric measurement was made in 1 to 2 h with a precision of 0.3%. Data were interpreted using thermodynamic and hydrodynamic computer calculations. For unconfined or lightly confined charges, the released energy is largely retained in the products, which are subsequently shocked considerably off the Chapman-Jouguet isentrope by reflections from the bomb wall. For heavily confined charges, the detonation energy is largely converted to kinetic and internal energy of the confining case, and the products expand with minimal reshock along the Chapman-Jouguet isentrope.

Ornellas, D. L.

1982-04-01

375

Sterols heating: degradation and formation of their ring-structure polar oxidation products.  

PubMed

Cholesterol and phytosterols can be oxidised under heating conditions to give sterol oxidation products (SOPs), known by their toxic effects. This paper studied the degradation of cholesterol and three plant sterols during a 360 min heating treatment (180 °C). The formation and further degradation of SOPs was also analysed by GC-MS. Results revealed a sterol susceptibility to degradation according to the following decreasing order: campesterol??-sitosterol?stigmasterol>cholesterol. The degradation curve fit (R(2)=0.907-0.979) a logarithmic model. SOPs increased their concentration during the first 5-10 min and thereafter, their degradation rate was higher than their formation rate, resulting in a decrease over time. Irrespective of the sterol from which they had derived, 7-keto derivatives presented the highest levels throughout the entire process, and also SOPs with the same type of oxidation followed a similar degradation pattern (R=0.90-0.99). PMID:22868149

Barriuso, Blanca; Otaegui-Arrazola, Ane; Menéndez-Carreño, María; Astiasarán, Iciar; Ansorena, Diana

2012-11-15

376

Advanced glycation end products co-localized with astrocytes and microglial cells in Alzheimer's disease brain.  

PubMed

In the previous study [Takeda et al. (1996) Neurosci Lett 221: 17-21], we reported that the advanced glycation end products (AGEs) in the external space of neuronal perikarya (extraneuroperikaryal AGE deposits) were significantly abundant in the Alzheimer's brain. In this study, we investigated the spatial relationship of the extraneuroperikaryal AGE (carboxymethyllysine and pentosidine) deposits in astrocytes and microglial cells in the Alzheimer's disease brain using double immunolabelling for AGEs and astrocyte or microglial cell markers. Most of the extraneuroperikaryal AGE deposits were co-localized with glial fibrillary acidic protein-positive astrocytes. AGE deposit-bearing astrocytes also contained Gomori-positive granules. Furthermore, some of the extraneuroperikaryal AGE deposits were co-localized with microglial cells. These extraneuroperikaryal AGEs may activate astrocyte and microglia, and play a role in pathogenesis of Alzheimer's disease. PMID:9650745

Takeda, A; Yasuda, T; Miyata, T; Goto, Y; Wakai, M; Watanabe, M; Yasuda, Y; Horie, K; Inagaki, T; Doyu, M; Maeda, K; Sobue, G

1998-06-01

377

Fatigue and heat production in repeated contractions of mouse skeletal muscle.  

PubMed Central

1. This study tested the hypothesis that moderate fatigue of skeletal muscle arises from a mismatch between energy demand and energy supply. Fatigue was defined as the decline in isometric force. Energy supply and demand were assessed from measurements of muscle heat production. 2. Experiments were performed in vitro (21 degrees C) with bundles of muscle fibres from mouse fast-twitch extensor digitorum longus muscle and slow-twitch soleus muscle. Fibre bundles were fatigued using a series of thirty isometric tetani. Cycle duration (time between successive tetani) was 5 s. The amount of fatigue that occurred during a series of tetani was varied by varying contraction duty cycle (tetanus duration/cycle duration) by varying tetanus duration. 3. Peak isometric force and total heat production in each cycle were measured. For each cycle, the amounts of initial heat (H(i)) and recovery heat (Hr) produced were calculated and used as indices of energy use and supply, respectively. H(i) and Hr were used to estimate the net initial chemical breakdown (in energy units) in each cycle (H(i,net)). 4. The magnitude of H(i,net) was greatest in the early stages of the contraction protocol when Hr was still increasing towards a steady value. The magnitude of decline in force between successive tetani was proportional to H(i,net) for both muscles. 5. The results are consistent with the idea that the development of moderate levels of fatigue at the start of a series of contractions is due to the rate of energy supply being inadequate to match the rate of energy use. PMID:8576863

Barclay, C J; Arnold, P D; Gibbs, C L

1995-01-01

378

Gas-dynamic shock heating of post-flare loops due to retraction following localized, impulsive reconnection  

E-print Network

We present a novel model in which shortening of a magnetic flux tube following localized, three-dimensional reconnection generates strong gas-dynamic shocks around its apex. The shortening releases magnetic energy by progressing away from the reconnection site at the Alfven speed. This launches inward flows along the field lines whose collision creates a pair of gas-dynamic shocks. The shocks raise both the mass density and temperature inside the newly shortened flux tube. Reconnecting field lines whose initial directions differ by more that 100 degrees can produce a concentrated knot of plasma hotter that 20 MK, consistent with observations. In spite of these high temperatures, the shocks convert less than 10% of the liberated magnetic energy into heat - the rest remains as kinetic energy of bulk motion. These gas-dynamic shocks arise only when the reconnection is impulsive and localized in all three dimensions; they are distinct from the slow magnetosonic shocks of the Petschek steady-state reconnection model.

D. W. Longcope; S. E. Guidoni; M. G. Linton

2008-10-20

379

Citrate-capped gold nanoparticle electrophoretic heat production in response to a time-varying radiofrequency electric-field  

PubMed Central

The evaluation of heat production from gold nanoparticles (AuNPs) irradiated with radiofrequency (RF) energy has been problematic due to Joule heating of their background ionic buffer suspensions. Insights into the physical heating mechanism of nanomaterials under RF excitations must be obtained if they are to have applications in fields such as nanoparticle-targeted hyperthermia for cancer therapy. By developing a purification protocol which allows for highly-stable and concentrated solutions of citrate-capped AuNPs to be suspended in high-resistivity water, we show herein, for the first time, that heat production is only evident for AuNPs of diameters ? 10 nm, indicating a unique size-dependent heating behavior not previously observed. Heat production has also shown to be linearly dependent on both AuNP concentration and total surface area, and severely attenuated upon AuNP aggregation. These relationships have been further validated using permittivity analysis across a frequency range of 10 MHz to 3 GHz, as well as static conductivity measurements. Theoretical evaluations suggest that the heating mechanism can be modeled by the electrophoretic oscillation of charged AuNPs across finite length scales in response to a time-varying electric field. It is anticipated these results will assist future development of nanoparticle-assisted heat production by RF fields for applications such as targeted cancer hyperthermia. PMID:23795228

Corr, Stuart J.; Raoof, Mustafa; Mackeyev, Yuri; Phounsavath, Sophia; Cheney, Matthew A.; Cisneros, Brandon T.; Shur, Michael; Gozin, Michael; McNally, Patrick J.; Wilson, Lon J.; Curley, Steven A.

2013-01-01

380

NDT&E International 40 (2007) 158167 Case depth determination in heat-treated industrial steel products using  

E-print Network

depth-profile generation for carburized and quenched AISI-8620 steels. They showed that the variationNDT&E International 40 (2007) 158­167 Case depth determination in heat-treated industrial steel-contact, non-intrusive determination of effective case depth in heat-treated case-hardened steel products

Mandelis, Andreas

381

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

382

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

383

Enhanced loss of fusion products during mode conversion heating in TFTR  

SciTech Connect

Ion Bernstein waves (IBWS) have been generated by mode conversion of ion cyclotron range of frequency (ICRF) fast waves in TFTR. The loss rate of fusion products in these discharges can be large, up to 10 times the first orbit loss rate. The losses are observed at the passing/trapped boundary, indicating that passing particles are being moved onto loss orbits either by increase of their v{perpendicular} due to the wave, by outward transport in minor radius, or both. The lost particles appear to be DD fusion produced tritons heated to {approximately}1.5 times their birth energy.

Darrow, D.S.; Majeski, R.; Fisch, N.J.; Heeter, R.F.; Herrmann, H.W.; Herrmann, M.C.; Zarnstorff, M.C.; Zweben, S.J.

1995-07-01

384

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

385

Solution of the inverse heat conduction problem for controlling and monitoring temperature fields in a layer of dispersed product  

NASA Astrophysics Data System (ADS)

A mathematical model of data transmission from the site of self-warming in a dispersed system with distributed parameters is suggested which allows one to perform systematic calculations of the parameters of the process of heat propagation in a silo tower. The inverse heat conduction problem is solved allowing one, by using information signals on the current temperature of a granular bed, to promptly guard against the occurrence of local sites of self-warming under conditions of grain storage.

Shevtsov, A. A.; Pavlov, I. O.; Voronova, E. V.; Britikov, D. A.

2012-07-01

386

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

387

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

388

The role of radiogenic heat production in the generation of ultra high temperature crustal metamorphism  

NASA Astrophysics Data System (ADS)

How the Earth’s crust can reach temperatures greater than 900°C at depths less than 40 km to produce ultrahigh temperature (UHT) metamorphism is a question exercising the minds of many researchers. Many models of continental geothermal gradients fail to account for this type of metamorphism yet natural examples of these rocks are being identified more frequently in orogenic belts around the world. UHT metamorphism is best preserved in rocks of sedimentary origin. This is in part because sedimentary rocks have chemical compositions that generate distinctive mineral phases under conditions of extreme temperature, but there also is a strong indication that this style of metamorphism is often associated with tectonic inversion of a sedimentary basin. It is widely accepted that such high geothermal gradients require thickening of crustal rocks that are either already anomalously hot, or have the potential to become so through elevated concentrations of U, Th and K. The applicability of these models hinges on two key factors (1) that there is a threshold enrichment of the relevant crustal column in U, Th and K and (2) the crust has enough time to respond conductively to the heat generated through the radioactive decay of these elements. In this presentation we will examine these two factors in an ideal natural laboratory, the Madurai Block of the Southern Granulite Terrane, India. We will constrain the duration of high-geothermal metamorphism through the application of in-situ Sensitive High Resolution Ion Probe (SHRIMP) geochronology linked to the development of UHT mineral assemblages. We will also present 1D numerical models for the temporal evolution of geothermal gradients in these rocks. Our models couple the temperature dependence of thermal conductivity and heat capacity from recent studies with in-situ radiogenic heat production measurements from lithologies within the Madurai Block and integrate the effect of the consumption of heat due to the initiation of partial melting. Geotherms calculated at 5, 10, 20, 40, 60, 80 and 120 Myr after crustal thickening for a pre-thickened uniform distribution of heat production of 2.5 ?m-3 in the upper 20 km and 0.4 ?m-3 from 20 - 35 km.

Clark, C.; Healy, D.

2009-12-01

389

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

390

Heat production in cold and long scotophase acclimated and winter acclimatized rodents  

NASA Astrophysics Data System (ADS)

Heat production by means of oxygen consumptionVo2 (at Ta = 6° C, 25° C, 30° C, and 32° C) and non-shivering thermogenesis (NST) were studied in individuals of a diurnal rodent ( Rhabdomys pumilio) and a nocturnal rodent ( Praomys natalensis). The studied mice were acclimated to cold at Ta=8°C with a photoperiod of LD 12:12. On the otherhand specimens of these two species were acclimated at Ta=25°C with a long scotophase LD8:16. The results were compared with a control group (Ta=25° C, LD 12:12) and winter acclimatized individuals of both species.Vo2 in cold acclimated mice of both species was significantly increased when compared to the control group and was even higher than the winter acclimatized group when measured below the lower critical temperature. Long scotophase acclimated mice of both species also increased their oxygen consumption significantly when compared to the control group. NST was significantly increased in long scotophase acclimated mice from both species when compared to the control group. The results of this study indicate that the effects of acclimation to long scotophase are similar to those of cold acclimation. As changes in photoperiod are regular, it may be assumed that heat production mechanisms in acclimatization to winter will respond to changes in photoperiodicity.

Haim, A.; Fourie, F. Le R.

1980-09-01

391

Effect of egg size on heat production and the transition of energy from egg to hatchling.  

PubMed

An experiment was conducted to study the effect of egg size on embryo development, heat production, and energy partitioning between egg and hatchling. Small (56.1 +/- 0.12 g SEM) and large (70.0 +/- 0.11 g SEM) hatching eggs were incubated in climate respiration chambers, and eggshell temperature was maintained constant at 37.8 degrees C in both egg weight classes by adjusting machine temperature. Dry matter, ash, protein, and fat contents were determined in albumen, yolk, yolk-free body (YFB), and residual yolk (RY), and carbohydrate contents and caloric values were calculated. To achieve a constant eggshell temperature, machine temperature needed to be set lower from d 15 onward, coinciding with increased heat production in large eggs compared with small eggs. Selective nutrient uptake resulted in higher fat content and lower protein content in RY in chicks that hatched from small eggs compared with large eggs. The respiration quotient in small and large eggs was the same, and embryos in small and large eggs were equally efficient in the transfer of energy from egg to YFB. The surplus availability of nutrients in large eggs was therefore held responsible for the absolute and relative higher weight of RY in chicks that hatched from large eggs compared with small eggs. PMID:16615362

Lourens, A; Molenaar, R; van den Brand, H; Heetkamp, M J W; Meijerhof, R; Kemp, B

2006-04-01

392

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

393

Global versus local environmental impacts of grazing and confined beef production systems  

NASA Astrophysics Data System (ADS)

Carbon footprint is a key indicator of the contribution of food production to climate change and its importance is increasing worldwide. Although it has been used as a sustainability index for assessing production systems, it does not take into account many other biophysical environmental dimensions more relevant at the local scale, such as soil erosion, nutrient imbalance, and pesticide contamination. We estimated carbon footprint, fossil fuel energy use, soil erosion, nutrient imbalance, and risk of pesticide contamination for five real beef background-finishing systems with increasing levels of intensification in Uruguay, which were combinations of grazing rangelands (RL), seeded pastures (SP), and confined in feedlot (FL). Carbon footprint decreased from 16.7 (RL-RL) to 6.9 kg (SP-FL) CO2 eq kg body weight-1 (BW; ‘eq’: equivalent). Energy use was zero for RL-RL and increased up to 17.3 MJ kg BW-1 for SP-FL. Soil erosion values varied from 7.7 (RL-RL) to 14.8 kg of soil kg BW-1 (SP-FL). Nitrogen and phosphorus nutrient balances showed surpluses for systems with seeded pastures and feedlots while RL-RL was deficient. Pesticide contamination risk was zero for RL-RL, and increased up to 21.2 for SP-FL. For the range of systems studied with increasing use of inputs, trade-offs were observed between global and local environmental problems. These results demonstrate that several indicators are needed to evaluate the sustainability of livestock production systems.

Modernel, P.; Astigarraga, L.; Picasso, V.

2013-09-01

394

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

395

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

396

24 CFR 200.950 - Building product standards and certification program for solar water heating system.  

Code of Federal Regulations, 2010 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...

2010-04-01

397

24 CFR 200.950 - Building product standards and certification program for solar water heating system.  

...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

398

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

399

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

400

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

401

Localizing the Holy Grail: Glacial/interglacial variations in atmospheric CO2 and oceanic deepwater production  

NASA Astrophysics Data System (ADS)

The 'Holy Grail' of glacial/interglacial CO_2 research is to identify the major driver for variations in atmospheric CO_2 on this time scale. A simple mechanism has hitherto remained elusive. I use an entirely new approach to the problem, namely a global vertical advection-diffusion balance of tracers in the ocean which shows that the ocean's deepwater production (DWP) is the sought-after physical mechanism. The model adequately reproduces modern pCO_2 and vertical profiles of temperature, ?CO_2, Alkalinity, PO_4, and O_2 in the ocean. Based on recently advanced compelling evidence for reduced glacial DWP, the model will then be shown to explain the glacial pCO_2 of 200~?atm. over a full glacial/interglacial transition (20~ky), model results excellently reproduce the observed temporal evolution of atmospheric CO_2 and deep ocean CaCO_3 saturation. The mechanism also explains the remarkable correlation between Antarctic temperature and CO_2 as recorded in ice cores. The ocean's deepwater production rate is hence identified as the dominant driver of glacial/interglacial CO_2 variations through its effect on the vertical distribution of heat and elements in the sea, initially set into motion in the Southern Hemisphere.

Zeebe, R. E.

2003-04-01

402

An evolutionary-based inverse approach for the identification of non-linear heat generation rates in living tissues using a localized meshless method  

Microsoft Academic Search

Purpose – This paper aims to develop and describe an improved process for determining the rate of heat generation in living tissue. Design\\/methodology\\/approach – Previous work by the authors on solving the bioheat equation has been updated to include a new localized meshless method which will create a more robust and computationally efficient technique. Inclusion of this technique will allow

Kevin Erhart; Eduardo Divo; Alain Kassab

2008-01-01

403

Non-local Heat Transport, Rotation Reversals and Up/Down Impurity Density Asymmetries in Alcator C-Mod Ohmic L-mode Plasmas  

NASA Astrophysics Data System (ADS)

Several seemingly unrelated phenomena in Alcator C-Mod Ohmic L-mode plasmas are shown to be closely connected: non-local heat transport, core toroidal rotation reversals, energy confinement saturation, up/down impurity density asymmetries and turbulence changes. These phenomena all abruptly transform at a critical value of the collisionality.

Rice, John; Gao, Chi; Reinke, Matt; Diamond, Patrick; Howard, Nate; Sun, Hongjuan; Cziegler, Istvan; Hubbard, Amanda; Podpaly, Yuri; Rowan, William; Terry, Jim; Chilenski, Mark; Delgado-Aparicio, Luis; Ennever, Paul; Ernst, Darin; Greenwald, Martin; Hughes, Jerry; Ma, Yunxing; Marmar, Earl; Porkolab, Miklos; Wolfe, Steve

2012-10-01

404

Heating Safety  

MedlinePLUS

... for heating. • Have a qualified professional install stationary space heating equipment, water heaters or central heating equipment according to the local codes and manufacturer’s instructions. • Maintain heating ... • For fuel burning space heaters, always use the proper fuel as specified ...

405

The contribution of skin blood flow in warming the skin after the application of local heat; the duality of the Pennes heat equation  

Microsoft Academic Search

As predicted by the Pennes equation, skin blood flow is a major contributor to the removal of heat from an external heat source. This protects the skin from erythema and burns. But, for a person in a thermally neutral room, the skin is normally much cooler than arterial blood. Therefore, if skin blood flow (BF) increases, it should initially warm

Jerrold Petrofsky; Dominic Paluso; Devyn Anderson; Kristin Swan; Jong Eun Yim; Vengatesh Murugesan; Tirupathi Chindam; Neha Goraksh; Faris Alshammari; Haneul Lee; Moxi Trivedi; Akshay N. Hudlikar; Vahishta Katrak

2011-01-01

406

Human white adipocytes express the cold receptor TRPM8 which activation induces UCP1 expression, mitochondrial activation and heat production.  

PubMed

Mammals possess two types of adipose tissue, white (WAT) and brown (BAT). The uncoupling protein 1 (UCP1) is a hallmark of BAT, being the pivotal player for cold-induced thermogenesis. WAT can acquire BAT characteristics with up-regulation of UCP1 after cold exposure or adrenergic stimulation. In the present study we demonstrated that human white adipocytes express the cold-sensing receptor TRPM8 which activation by menthol and icilin induced a rise in [Ca²?](i) and UCP1 expression, increased mitochondrial membrane potential, glucose uptake and heat production. The induction of "brown-like" phenotype in human white adipocytes after TRPM8 activation was supported by ultrastructural morphological changes of mitochondrial morphology and of their intracellular localization, with no modifications of the genes regulating mitochondrial biogenesis. In conclusion human white adipocytes express the cold receptor TRPM8 which activation induces their "browning" supporting a possible role of this receptor in the control of adipose tissue metabolism and body energy balance. PMID:24342393

Rossato, Marco; Granzotto, Marnie; Macchi, Veronica; Porzionato, Andrea; Petrelli, Lucia; Calcagno, Alessandra; Vencato, Juri; De Stefani, Diego; Silvestrin, Valentina; Rizzuto, Rosario; Bassetto, Franco; De Caro, Raffaele; Vettor, Roberto

2014-03-01

407

Toxic metals in food products originating from locally reared animals in Kuwait  

SciTech Connect

The toxicity of certain heavy metals such as Pb, Hg and Cd is well documented. The effect of environmental pollution on contamination of foods and on their safety for human consumption is a serious global public concern, and data on this subject have been reported by several investigators. Since traces of heavy metals are found in almost every food commodity, an estimation of the intake of food contaminants is essential and differs considerably from country to country. In Kuwait, data are not available on the levels of toxic metals in foods consumed by the various age groups nor are there any Kuwaiti standards at present on the permissible limits of these metals in various food commodities. Hence, the dietary intake of these elements cannot be determined accurately. The aim of this study was to investigate the levels of certain toxic metals in locally produced animal products. 19 refs., 2 tabs.

Husain, A.; Al-Rashdan, A.; Al-Awadhi, A.; Mahgoub, B.; Al-Amiri, H. [Kuwait Institute for Scientific Research, Safat (Kuwait)] [Kuwait Institute for Scientific Research, Safat (Kuwait)

1996-12-31

408

Departure from corotation of the Io plasma torus - Local plasma production  

NASA Technical Reports Server (NTRS)

The departure of the Jovian magnetosphere from rigid corotation is adequately explained by outward plasma transport at distances where L is greater than approximately 10. The departure of 5% observed in the Io plasma torus, however, is too large to be accounted for simply by plasma transport. Local plasma production is proposed as the main factor determining the corotation lag in the torus. The outward pick-up current provided by ionization of neutral atoms is calculated and related to the current produced in the ionosphere by the corotation lag. This leads to an expression giving the corotation lag of the torus as a function of radial distance. Charge transfer is found to be an important process, allowing the majority of the torus mass to be ejected from the magnetosphere in a neutral state. Thus, the mass loading rate is found to be several times that inferred from examination of the corotation lag associated with outward plasma transport.

Pontius, D. H., Jr.; Hill, T. W.

1982-01-01

409

Assessing the market potential for a local food product : Evidence from a non-hypothetical economic experiment  

Microsoft Academic Search

Purpose – The purpose of this paper is to analyze the market potential of a locally produced and high quality food product (i.e. white bean “Mongeta Ganxet” (MG)) from Catalonia, Spain. Consumers' willingness to pay (WTP) for the product is elicited using a non-hypothetical economic experiment and then the sensitivity of WTP values is analyzed with regard to additional information

Faical Akaichi; José M. Gil; Rodolfo M. Nayga

2012-01-01

410

Systemic but not local infections elicit immunosuppressive IL-10 production by Natural Killer cells  

PubMed Central

Summary IL-10 is an anti-inflammatory mediator, important in limiting immunopathology. Its impact is influenced both by the timing and localization of its release. Here we show that NK cells rapidly express IL-10 during acute infection with the rapidly disseminating pathogens Toxoplasma gondii, Listeria monocytogenes or Yersinia pestis. Direct IL-12 signals proved necessary and sufficient for NK induction of IL-10. NK cells from T. gondii-infected mice inhibited dendritic cell release of IL-12 in an IL-10-dependent manner and NK cell depletion resulted in elevated serum IL-12. Together these data suggest an innate, negative feedback loop, in which IL-12 limits its own production by eliciting IL-10 from NK cells. In contrast to the systemic pathogens, NK cell IL-10 was not elicited by locally restricted infection with influenza virus or with a Y. pestis strain attenuated to prevent dissemination. Thus, systemic infections uniquely engage NK cells in an IL-10-mediated immunoregulatory circuit that functions to alleviate inflammation during sepsis. PMID:20006839

Perona-Wright, Georgia; Mohrs, Katja; Szaba, Frank M.; Kummer, Lawrence W.; Madan, Rajat; Karp, Christopher L.; Johnson, Lawrence L.; Smiley, Stephen T.; Mohrs, Markus

2009-01-01

411

Association of Nuclear-Localized Nemo-Like Kinase with Heat-Shock Protein 27 Inhibits Apoptosis in Human Breast Cancer Cells  

PubMed Central

Nemo-like kinase (NLK), a proline-directed serine/threonine kinase regulated by phosphorylation, can be localized in the cytosol or in the nucleus. Whether the localization of NLK can affect cell survival or cell apoptosis is yet to be disclosed. In the present study we found that NLK was mainly localized in the nuclei of breast cancer cells, in contrast to a cytosolic localization in non-cancerous breast epithelial cells. The nuclear localization of NLK was mediated through direct interaction with Heat shock protein 27 (HSP27) which further protected cancer cells from apoptosis. The present study provides evidence of a novel mechanism by which HSP27 recognizes NLK in the breast cancer cells and prevents NLK-mediated cell apoptosis. PMID:24816797

Zarrizi, Reihaneh; Hellman, Ulf; Karlsson, Per; Helou, Khalil; Massoumi, Ramin

2014-01-01

412

New heat flow measurements in the Ulleung Basin, East Sea (Sea of Japan): relationship to local BSR depth,  

E-print Network

ORIGINAL New heat flow measurements in the Ulleung Basin, East Sea (Sea of Japan): relationship-situ measurements, despite the precautions taken to preserve the cores. Based on the in-situ conductivity, the heat sea level, respectively. Introduction Seafloor heat flow measurements have made important

413

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

414

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

415

Heat transfer and pressure distributions on hemisphere-cylinders in methane-air combustion products at Mach 7  

NASA Technical Reports Server (NTRS)

Heat-transfer and pressure distributions were measured over the surfaces of three hemisphere-cylinder models tested at a nominal Mach number of 7 in the Langley 8-foot high-temperature structures tunnel which uses methane-air products of combustion as a test medium. The results showed that the heat-transfer and pressure distributions over the surface of the models were in good agreement with experimental data obtained in air and also with theoretical predictions.

Weinstein, I.

1973-01-01

416

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

417

Heat of Combustion of the Product Formed by the Reaction of Diborane with 1,3-Butadiene  

NASA Technical Reports Server (NTRS)

The net heat of combustion of the product formed by the reaction of diborane with 1,3-butadiene was found to be 18,700+/-150 Btu per pound for the reaction of liquid fuel to gaseous carbon dioxide, gaseous water, and solid boric oxide. The measurements were made in a Parr oxygen-bomb calorimeter, and the combustion was believed to be 98 percent complete. The estimated net heat of combustion for complete combustion would therefore be 19,075+/-150 Btu per pound. Since this value is approximately the same as the heat of combustion of butadiene, it seems certain that the material is partially oxidized.

Tannenbaum, Stanley; Allen, Harrison, Jr.

1953-01-01

418

Co-composting of eggshell waste in self-heating reactors: monitoring and end product quality.  

PubMed

Industrial eggshell waste (ES) is classified as an animal by-product not intended to human consumption. For reducing pathogen spreading risk due to soil incorporation of ES, sanitation by composting is a pre-treatment option. This work aims to evaluate eggshell waste recycling in self-heating composting reactors and investigate ES effect on process evolution and end product quality. Potato peel, grass clippings and rice husks were the starting organic materials considered. The incorporation of 30% (w/w) ES in a composting mixture did not affect mixture biodegradability, nor its capacity to reach sanitizing temperatures. After 25 days of composting, ES addition caused a nitrogen loss of about 10 g N kg(-1) of initial volatile solids, thus reducing nitrogen nutritional potential of the finished compost. This study showed that a composting mixture with a significant proportion of ES (30% w/w) may be converted into calcium-rich marketable compost to neutralize soil acidity and/or calcium deficiencies. PMID:24055972

Soares, Micaela A R; Quina, Margarida M J; Quinta-Ferreira, Rosa M

2013-11-01

419

Nitric oxide production and tolerance differ among Symbiodinium types exposed to heat stress.  

PubMed

Nitric oxide (NO) is a ubiquitous molecule and its involvement in metazoan-microbe symbiosis is well known. Evidence suggests that it plays a role in the temperature-induced breakdown ('bleaching') of the ecologically important cnidarian-dinoflagellate association, and this can often lead to widespread mortality of affected hosts. This study confirms that dinoflagellates of the genus Symbiodinium can produce NO and that production of the compound is differentially regulated in different types when exposed to elevated temperature. Temperature-sensitive type B1 cells under heat stress (8°C above ambient) exhibited significant increases in NO synthesis, which occurred alongside pronounced photoinhibition and cell mortality. Tolerant type A1 cells also displayed increases in NO production, yet maintained photosynthetic yields at levels similar to those of untreated cells and displayed less dramatic increases in cell death. Type C1 cells displayed a down-regulation of NO synthesis at high temperature, and no significant mortality increases were observed in this type. Temperature-induced mortality in types A1 and B1 was affected by the prevailing level of NO and, furthermore, photosynthetic yields of these temperature-tolerant and -sensitive types appeared differentially susceptible to NO donated by pharmacological agents. Taken together, these differences in NO synthesis and tolerance could potentially influence the varying bleaching responses seen among hosts harboring different Symbiodinium types. PMID:22992385

Hawkins, Thomas D; Davy, Simon K

2012-11-01

420

Heat of Combustion of the Product Formed by the Reaction of Acetylene and Diborane (LFPL-CZ-3)  

NASA Technical Reports Server (NTRS)

The heat of combustion of the product formed by the reaction acetylene and diborane was found to be 20,100 +/- 100 Btu per pound for the reaction of liquid fuel to gaseous carbon dioxide, gaseous water, and solid boric oxide. The measurements were made in a Parr oxygen-bomb calorimeter, and chemical analyses both of the sample and of the combustion products indicated combustion in the bomb calorimeter to have been 97 percent complete. The estimated net heat of combustion for complete combustion would therefore be 20,700 +/- 100 Btu per pound.

Allen, Harrison, Jr.; Tannenbaum, Stanley

1957-01-01

421

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

422

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

423

Fault region localization (FRL): collaborative product and process improvement based on field performance  

NASA Astrophysics Data System (ADS)

Customer feedback in the form of warranty/field performance is an important and direct indicator of quality and robustness of a product. Linking warranty information to manufacturing measurements can identify key design parameters and process variables (DPs and PVs) that are related to warranty failures. Warranty data has been traditionally used in reliability studies to determine failure distributions and warranty cost. This paper proposes a novel Fault Region Localization (FRL) methodology to map warranty failures to manufacturing measurements (hence to DPs/PVs) to diagnose warranty failures and perform tolerance revaluation. The FRL methodology consists of two parts: 1. Identifying relations between warranty failures and DPs and PVs using the Generalized Rough Set (GRS) method. GRS is a supervised learning technique to identify specific DPs and PVs related to the given warranty failures and then determining the corresponding Warranty Fault Regions (WFR), Normal Region (NR) and Boundary region (BND). GRS expands traditional Rough Set method by allowing inclusion of noise and uncertainty of warranty data classes. 2. Revaluating the original tolerances of DPs/PVs based on the WFR and BND region identified. The FRL methodology is illustrated using case studies based on two warranty failures from the electronics industry.

Mannar, Kamal; Ceglarek, Darek

2005-11-01

424