STECH VOL5 (1) FEBRUARY, 2016

African Journals Online (AJOL)

Copyright 1AARR 2012-2016: www.afrrevjo.net

STECH VOL 5 (1) FEBRUARY, 2016. Vol. 5 (1), S/No11, February, 2016: 1-13 ..... Knowledge produce is an act of discovery which involves exploring, analyzing .... Architectural Research, Elsevier: Higher Education Press Limited Company.

Development on the High-throughput Vol-oxidizer for Decladding and Voloxidation of Spent Fuel Rod-cuts

International Nuclear Information System (INIS)

Kim, Young Hwang; Jung, Jae Hoo; Kim, Ki Ho; Park, Byung Buk; Lee, Hyo Jik; Kim, Sung Hyun; Park, Hee Sung; Lee, Jong Kwang; Kim, Ho Dong

2009-12-01

A high-throughput vol-oxidizer which can handle a several ten kg HM/batch is being developed to supply U 3 O 8 powders to an electrolytic reduction reactor in pyro-processing. At the first year step(2007), for enhancement of oxidation and recovery rate, we analyzed the mechanical and chemical methods, and devised the main mechanism with ball drop methods and rotary kiln type. Also, the main devices for oxidation and recovery of rod-cuts were designed by using the Solid Works and COSMOS program tools, and manufactured after thermal/mechanical analysis. In order to verify the main devices, simulation fuels(W 90%+SiO 2 10%) were manufactured and the main devices were tested for the oxidation and recovery rate of its. Here the expansion ratio of simulation fuel is similar to U 3 O 8 (2.7). At the second year step(2008), with the constant ration of rod-cuts volume and expansion ratio of U 3 O 8 (2.7), we produced a theoretical equation that can estimate the volume of rod-cuts according to a variation of their weight and lengths. We considered various materials such as ceramics and Ni-Cr, finally, the APM material which can constantly maintain against high temperature(1,200 .deg. C) and vacuum(1 torr) was selected and a vol-oxidizer was designed. At the third year step(2009), in order to manufacture a high-throughput vol-oxidizer, we have analyzed the vol-oxidizer for remote operability and maintainability, also the remote assembling and disassembling possibilities of the selected modules have been analyzed in terms of visibility, interference, approach, weight, and so on. We have presented final modular design and manufactured a high-throughput vol-oxidizer. Also, we have conducted the blank, heating(over 500 .deg. C) and hull separation test(capacity : 50 kg HM/batch, hull length 50mm) on the high-throughput vol-oxidizer. Also, these design technologies for the high-throughput vol-oxidizer will be utilized in the development of a more efficient vol-oxidizer with higher

Fuels for the oil-fuelled heating system of the future; Brennstoffe fuer die Oelheiztechnik der Zukunft

Energy Technology Data Exchange (ETDEWEB)

Rheinberg, O. van [Oel-Waerme-Institut GmbH, An-Institut der RWTH Aachen, Herzogenrath (Germany). Abt. Energietraeger

2011-02-15

For ecological and political reasons bio-heating-oil of up to 10.9 vol.% of Fatty-Acid-Methyl-Ester (FAME) is available in the market. For new installations the appliance industry has approved their products for the use of this bio-heating-oil. For existing oil firing plants minor changes are necessary. These are the use of qualified oil burner pumps, oil tubes, oil pre-filter and the change to single chord system in order to avoid the continuous circulation of heating oil. Due to the chemical and physical properties an admixture of up to 20.9 vol.% of FAME in heating oil sulphur low is feasible. One of the main requirements to introduce such fuel in the market is the guarantee of storage stability over several years even by such high levels of FAME. To reach this goal an accurate predictability of fuel stability and different actions for the stabilisation of such bio-heating oil are necessary. Hence several investigations are undertaken at Oel-Waerme-Institut to ensure higher levels of FAME or of other alternative fuels in the future. (orig.)

High Flux Heat Exchanger

Science.gov (United States)

1993-01-01

maximum jet velocity (6.36 m/s), and maximum number of jets (nine). Wadsworth and Mudawar [49] describe the use of a single slotted nozzle to provide...H00503 (ASME), pp. 121-128, 1989. 40 49. D. C. Wadsworth and I. Mudawar , "Cooling of a Multichip Electronic Module by Means of Confined Two-Dimensional...Jets of Dielectric Liquid," HTD-Vol. 111, Heat Transfer in Electrglif, Book No. H00503 (ASME), pp. 79-87, 1989. 50. D.C. Wadsworth and I. Mudawar

Melt extraction during heating and cooling of felsic crystal mushes in shallow volcanic systems: An experimental study

Science.gov (United States)

Pistone, M.; Baumgartner, L. P.; Sisson, T. W.; Bloch, E. M.

2017-12-01

The dynamics and kinetics of melt extraction in near-solidus, rheologically stalled, felsic crystal mushes (> 50 vol.% crystals) are essential to feeding many volcanic eruptions. At shallow depths (volatile-saturated and may be thermally stable for long time periods (104-107 years). In absence of deformation, residual melt can segregate from the mush's crystalline framework stimulated by: 1) gas injecting from hot mafic magmas into felsic mushes (heating / partial melting scenario), and 2) gas exsolving from the crystallizing mush (cooling / crystallizing scenario). The conditions and efficiency of melt extraction from a mush in the two scenarios are not well understood. Thus, we conducted high-temperature (700 to 850 °C) and -pressure (1.1 kbar) cold seal experiments (8-day duration) on synthetic felsic mushes, composed of water-saturated (4.2 wt.%) rhyodacite melt bearing different proportions of added quartz crystals (60, 70, and 80 vol%; 68 mm average particle size). High-spatial resolution X-ray tomography of run products show: 1) in the heating scenario (> 750 °C) melt has not segregated due to coalescence of vesicles (≤ 23 vol%) and large melt connectivity (> 7 vol% glass) / low pressure gradient for melt movement up to 80 vol% crystals; 2) in the cooling scenario (≤ 750 °C) vesicle (< 11 vol%) coalescence is limited or absent and limited amount of melt (3 to 11 vol%) segregated from sample center to its outer periphery (30 to 100 mm melt-rich lenses), testifying to the efficiency of melt extraction dictated by increasing crystallinity. These results suggest that silicic melt hosted within a crystal-rich mush can accumulate rapidly due to the buildup of modest gas pressures during crystallization at temperatures near the solidus.

Modification of embryonic resistance to heat shock in cattle by melatonin and genetic variation in HSPA1L.

Science.gov (United States)

Ortega, M Sofia; Rocha-Frigoni, Nathália A S; Mingoti, Gisele Zoccal; Roth, Zvi; Hansen, Peter J

2016-11-01

The objectives were to test whether (1) melatonin blocks inhibition of embryonic development caused by heat shock at the zygote stage, and (2) the frequency of a thermoprotective allele for HSPA1L is increased in blastocysts formed from heat-shocked zygotes as compared with blastocysts from control zygotes. It was hypothesized that melatonin prevents effects of heat shock on development by reducing accumulation of reactive oxygen species (ROS) and that embryos inheriting the thermoprotective allele of HSPA1L would be more likely to survive heat shock. Effects of 1 µM melatonin on ROS were determined in experiments 1 and 2. Zygotes were cultured at 38.5 or 40°C for 3 h in the presence of CellROX reagent (ThermoFisher Scientific, Waltham, MA). Culture was in a low [5% (vol/vol)] oxygen (experiment 1) or low or high [21% (vol/vol)] oxygen environment (experiment 2). Heat shock and high oxygen increased ROS; melatonin decreased ROS. Development was assessed in experiments 3 and 4. In experiment 3, zygotes were cultured in low oxygen ± 1 µM melatonin and exposed to 38.5 or 40°C for 12 h (experiment 1) beginning 8 h after fertilization. Melatonin did not protect the embryo from heat shock. Experiment 4 was performed similarly except that temperature treatments (38.5 or 40°C, 24 h) were performed in a low or high oxygen environment (2×2 × 2 factorial design with temperature, melatonin, and oxygen concentration as main effects), and blastocysts were genotyped for a deletion (D) mutation (C→D) in the promoter region of HSPA1L associated with thermotolerance. Heat shock decreased percent of zygotes developing to the blastocyst stage independent of melatonin or oxygen concentration. Frequency of genotypes for HSPA1L was affected by oxygen concentration and temperature, with an increase in the D allele for blastocysts that developed in high oxygen and following heat shock. It was concluded that (1) lack of effect of melatonin or oxygen concentration on embryonic

Development of new heat transfer media for improving efficiency in energy systems : conventional fluids and nanofluids

OpenAIRE

Cabaleiro Alvarez, David

2016-01-01

This PhD Thesis aims to characterize different conventional thermal fluids and propose new nanofluids based on their thermophysical, rheological, (solid-liquid) phase equilibria and their capability to heat transfer or heat storage. The selected conventional fluids are commonly used in the majority of heat transfer systems such as ethylene glycol (EG), propylene glycol (PG), a (ethylene glycol + water) mixture at 50 vol.% (EG+W), or the (diphenyl ether + biphenyl) mixtures. The nanofluids wer...

Crisis Communication (Handbooks of Communication Science Vol. 23)

DEFF Research Database (Denmark)

Johansen, Winni

Vol. 23 - The Handbook of Communication Science General editors: Peter J. Schultz and Paul Cobley......Vol. 23 - The Handbook of Communication Science General editors: Peter J. Schultz and Paul Cobley...

Numerical investigation of heat transfer characteristics in utility boilers of oxy-coal combustion

International Nuclear Information System (INIS)

Hu, Yukun; Li, Hailong; Yan, Jinyue

2014-01-01

Highlights: • Air-coal and oxy-coal combustion in an industrial scale PF boiler were simulated in ANSYS FLUENT. • The O 2 concentration of 33 vol% in the oxy-coal combustion case matches the air-coal combustion case most closely. • The moisture in the flue gas has little impact on flame temperature, but positive impact on surface incident radiation. - Abstract: Oxy-coal combustion has different flue gas composition from the conventional air-coal combustion. The different composition further results in different properties, such as the absorption coefficient, emissivity, and density, which can directly affect the heat transfer in both radiation and convection zones of utility boilers. This paper numerically studied a utility boiler of oxy-coal combustion and compares with air-coal combustion in terms of flame profile and heat transferred through boiler side walls in order to understand the effects of different operating conditions on oxy-coal boiler retrofitting and design. Based on the results, it was found that around 33 vol% of effective O 2 concentration ([O 2 ] effective ) the highest flame temperature and total heat transferred through boiler side walls in the oxy-coal combustion case match to those in the air-coal combustion case most; therefore, the 33 vol% of [O 2 ] effective could result in the minimal change for the oxy-coal combustion retrofitting of the existing boiler. In addition, the increase of the moisture content in the flue gas has little impact on the flame temperature, but results in a higher surface incident radiation on boiler side walls. The area of heat exchangers in the boiler was also investigated regarding retrofitting. If boiler operates under a higher [O 2 ] effective , to rebalance the load of each heat exchanger in the boiler, the feed water temperature after economizer can be reduced or part of superheating surfaces can be moved into the radiation zone to replace part of the evaporators

A numerical investigation of γ-Al2O3-water nanofluids heat transfer and pressure drop in a shell and tube heat exchanger

Directory of Open Access Journals (Sweden)

P. Shahmohammadi

2016-01-01

Full Text Available The effect of γ-Al2O3 nanoparticles on heat transfer rate, baffle spacing and pressure drop in the shell side of small shell and tube heat exchangers was investigated numerically under turbulent regime. γ-Al2O3-water nanofluids and pure water were used in the shell side and the tube side of heat exchangers, respectively. Since the properties of γ-Al2O3-water nanofluids were variable, they were defined using the user define function. The results revealed that heat transfer and pressure drop were increased with mass flow rate as well as baffle numbers. Adding nanoparticles to the based fluid did not have a significant effect on pressure drop in the shell side. The best heat transfer performance of heat exchangers was for γ-Al2O3-water 1 vol.% and higher nanoparticles concentration was not suitable. The suitable baffle spacing was 43.4% of the shell diameter, showing a good agreement with Bell-Delaware method.

Modified heat treatment for lower temperature improvement of the mechanical properties of two ultrahigh strength low alloy steels

Science.gov (United States)

Tomita, Yoshiyuki; Okabayashi, Kunio

1985-01-01

In the previous papers, a new heat treatment for improving the lower temperature mechanical propertise of the ultrahigh strength low alloy steels was suggested by the authors which produces a mixed structure of 25 vol pct lower bainite and 75 vol pct martensite through isothermal transformation at 593 K for a short time followed by water quenching (after austenitization at 1133 K). In this paper, two commercial Japanese ultrahigh strength steels, 0.40 pct C-Ni-Cr-Mo (AISI 4340 type) and 0.40 pct C-Cr-Mo (AISI 4140 type), have been studied to determine the effect of the modified heat treatment, coupled above new heat treatment with γ ⇆ α' repctitive heat treatment, on the mechanical properties from ambient temperature (287 K) to 123 K. The results obtained for various test temperatures have been compared with those for the new heat treatment reported previously and the conventional 1133 K direct water quenching treatment. The incorporation of intermediate four cyclic γ ⇆ α' repctitive heat treatment steps (after the initial austenitization at 1133 K and oil quenching) into the new heat treatment reported previously, as compared with the conventional 1133 K direct water quenching treatment, significantly improved 0.2 pct proof stress as well as notch toughness of the 0.40 pct C-Ni-Cr-Mo ultrahigh strength steel at similar fracture ductility levels from 287 to 123 K. Also, this heat treatment, as compared with the conventional 1133 K direct water quenching treatment, significantly improved both 0.2 pct proof stress and notch toughness of the 0.40 pct C-Cr-Mo ultrahigh strength steel with increased fracture ductility at 203 K and above. The microstructure consists of mixed areas of ultrafine grained martensite, within which is the refined blocky, highly dislocated structure, and the second phase lower bainite (about 15 vol pct), which appears in acicular form and partitions prior austenite grains. This newly developed heat treatment makes it possible to modify

Advances in boundary elements. Vol. 1-3

International Nuclear Information System (INIS)

Brebbia, C.A.; Connor, J.J.

1989-01-01

This book contains some of the edited papers presented at the 11th Boundary Element Conference, held in Cambridge, Massachusetts, during August 1989. The papers are arranged in three different books comprising the following topics: Vol. 1: Computations and Fundamentals - comprises sections on fundamentals, adaptive techniques, error and convergence, numerical methods and computational aspects. (283 p.). Vol. 2: Field and fluid flow solutions - includes the following topics: potential problems, thermal studies, electrical and electromagnetic problems, wave propagation, acoustics and fluid flow. (484 p.). Vol. 3: Stress analysis - deals with advances in linear problems, nonlinear problems, fracture mechanics, contact mechanics, optimization, geomechanics, plates and shells, vibrations and industrial applications. (450 p). (orig./HP)

Further comparisons of critical heat flux correlations for vertical tubes

International Nuclear Information System (INIS)

Govan, A.H.

1986-11-01

An earlier report by Govan (1984, AERE-R11298), described a data-bank of critical heat flux measurements in vertical upflow in tubes, and compared the predictions of the Harwell Annular Flow Model with two previously reported correlations. In this report two further correlations, those of Biasi [1967, Studies on burnout, Part 3] and Zuber [1961, Int. Devel. Heat Transfer, Part 2, PB230-236]/ Griffith,[1977, Nucl. Safety vol 18, no3] have been tested. These two correlations are used extensively in reactor design. Overall comparisons are given between all the correlations tested so far. (author)

Heat exchanger technologies for the global environment. PWR-Vol. 25

International Nuclear Information System (INIS)

Maurer, J.R.

1994-01-01

This is the Committee's largest compilation of papers in the fourteen years that ASME has sponsored one or more sessions at the Joint Power Generation Conference. In addition to the twenty-two papers offered at the conference, one session contained a panel discussion during which five industry specialists related their experiences and interpretations. Many of the presentations of the past few years have been made by authors from foreign lands as the conference has expanded to an international forum. This years' theme of global impact is included in the heat exchanger presentations from the USA and abroad. In addition, ASME has encouraged authors to make the subjects of their presentations more apropos to current concerns. New concepts and designs, particularly with PC programs in mind, is one specific area that is addressed. Other topics such as materials selection, coatings to extend performance life, minimizing the effects of microbiologically influenced corrosion, zebra mussel control and new approaches to heat transfer design are some of the subjects covered at the conference and in this volume. Nineteen papers have been processed separately for inclusion in the appropriate data bases

Magnetic nanofluid properties as the heat transfer enhancement agent

Directory of Open Access Journals (Sweden)

Roszko Aleksandra

2016-01-01

Full Text Available The main purpose of this paper was to investigate an influence of various parameters on the heat transfer processes with strong magnetic field utilization. Two positions of experimental enclosure in magnetic environment, two methods of preparation and three different concentrations of nanoparticles (0.0112, 0.056 and 0.112 vol.% were taken into account together with the magnetic field strength. Analysed nanofluids consisted of distilled water (diamagnetic and Cu/CuO particles (paramagnetic of 40–60 nm size. The nanofluids components had different magnetic properties what caused complex interaction of forces’ system. The heat transfer data and fluid flow structure demonstrated the influence of magnetic field on the convective phenomena. The most visible consequence of magnetic field application was the heat transfer enhancement and flow reorganization under applied conditions.

Continuing Medical Education - Vol 27, No 1 (2009)

African Journals Online (AJOL)

Continuing Medical Education - Vol 27, No 1 (2009). Journal Home > Archives > Vol 27, No 1 (2009). Log in or Register to get access to full text downloads. ... Addiction treatment · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. R Meyer ...

International Journal of Humanistic Studies - Vol 3 (2004)

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International Journal of Humanistic Studies - Vol 3 (2004). Journal Home > Archives > Vol 3 (2004). Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives. DOWNLOAD FULL TEXT ...

Heat pulse propagation studies on DIII-D and the Tokamak Fusion Test Reactor

Science.gov (United States)

Fredrickson, E. D.; Austin, M. E.; Groebner, R.; Manickam, J.; Rice, B.; Schmidt, G.; Snider, R.

2000-12-01

Sawtooth phenomena have been studied on DIII-D and the Tokamak Fusion Test Reactor (TFTR) [D. Meade and the TFTR Group, in Proceedings of the International Conference on Plasma Physics and Controlled Nuclear Fusion, Washington, DC, 1990 (International Atomic Energy Agency, Vienna, 1991), Vol. 1, pp. 9-24]. In the experiments the sawtooth characteristics were studied with fast electron temperature (ECE) and soft x-ray diagnostics. For the first time, measurements of a strong ballistic electron heat pulse were made in a shaped tokamak (DIII-D) [J. Luxon and DIII-D Group, in Proceedings of the 11th International Conference on Plasma Physics and Controlled Nuclear Fusion Research, Kyoto (International Atomic Energy Agency, Vienna, 1987), Vol. 1, p. 159] and the "ballistic effect" was stronger than was previously reported on TFTR. Evidence is presented in this paper that the ballistic effect is related to the fast growth phase of the sawtooth precursor. Fast, 2 ms interval, measurements on DIII-D were made of the ion temperature evolution following sawteeth and partial sawteeth to document the ion heat pulse characteristics. It is found that the ion heat pulse does not exhibit the very fast, "ballistic" behavior seen for the electrons. Further, for the first time it is shown that the electron heat pulses from partial sawtooth crashes (on DIII-D and TFTR) are seen to propagate at speeds close to those expected from the power balance calculations of the thermal diffusivities whereas heat pulses from fishbones propagate at rates more consistent with sawtooth induced heat pulses. These results suggest that the fast propagation of sawtooth-induced heat pulses is not a feature of nonlinear transport models, but that magnetohydrodynamic events can have a strong effect on electron thermal transport.

Dynamics of structures '89. Vol. 3

International Nuclear Information System (INIS)

1989-01-01

The proceedings, comprising 3 volumes published by the Plzen Centre of the Czechoslovak Society for Science and Technology (Vol. 1 and 2) and by Skoda Works in Plzen (Vol. 3), contain 107 papers, out of which 8 fall within the INIS Subject Scope; these deal with problems related to the earthquake resistance of nuclear power plants. Attention is paid to the evaluation of seismic characteristics of nuclear power plant equipment, to the equipment testing and to calculations of its dynamic characteristics under simulated seismic stress. (Z.M.)

Experimental analysis for heat transfer of nanofluid with wire coil turbulators in a concentric tube heat exchanger

Science.gov (United States)

Akyürek, Eda Feyza; Geliş, Kadir; Şahin, Bayram; Manay, Eyüphan

2018-06-01

Nanofluids are a novel class of heat transfer suspensions of metallic or nonmetallic nanopowders with a size of less than 100 nm in base fluids and they can increase heat transfer potential of the base fluids in various applications. In the last decade, nanofluids have become an intensive research topic because of their improved thermal properties and possible heat transfer applications. For comparison, an experiment using water as the working fluid in the heat exchanger without wire coils was also performed. Turbulent forced convection heat transfer and pressure drop characteristics of Al2O3-water nanofluids in a concentric tube heat exchanger with and without wire coil turbulators were experimentally investigated in this research. Experiments effected particle volume concentrations of 0.4-0.8 to 1.2-1.6 vol% in the Reynolds number range from 4000 to 20,000. Two turbulators with the pitches of 25 mm and 39 mm were used. The average Nusselt number increased with increasing the Reynolds number and particle concentrations. Moreover, the pressure drop of the Al2O3-water nanofluid showed nearly equal to that of pure water at the same Reynolds number range. As a result, nanofluids with lower particle concentrations did not show an important influence on pressure drop change. Nonetheless, when the wire coils used in the heat exchanger, it increased pressure drop as well as the heat transfer coefficient.

Hydrodynamic studies of CNT nanofluids in helical coil heat exchanger

Science.gov (United States)

Babita; Sharma, S. K.; Mital Gupta, Shipra; Kumar, Arinjay

2017-12-01

Helical coils are extensively used in several industrial processes such as refrigeration systems, chemical reactors, recovery processes etc to accommodate a large heat transfer area within a smaller space. Nanofluids are getting great attention due to their enhanced heat transfer capability. In heat transfer equipments, pressure drop is one of the major factors of consideration for pumping power calculations. So, the present work is aimed to study hydrodynamics of CNT nanofluids in helical coils. In this study, pressure drop characteristics of CNT nanofluid flowing inside horizontal helical coils are investigated experimentally. The helical coil to tube diameter was varied from 11.71 to 27.34 keeping pitch of the helical coil constant. Double distilled water was used as basefluid. SDBS and GA surfactants were added to stablilize CNT nanofluids. The volumetric fraction of CNT nanofluid was varied from 0.003 vol% to 0.051 vol%. From the experimental data, it was analyzed that the friction factor in helical coils is greater than that of straight tubes. Concentration of CNT in nanofluids also has a significant influence on the pressure drop/friction factor of helical coils. At a constant concentration of CNT, decreasing helical coil to tube diameter from 27.24 to 11.71, fanning friction factor of helical coil; f c increases for a constant value of p/d t. This increase in the value of fanning friction factor can be attributed to the secondary flow of CNT nanofluid in helical coils.

Diameter effect on critical heat flux

International Nuclear Information System (INIS)

Tanase, A.; Cheng, S.C.; Groeneveld, D.C.; Shan, J.Q.

2009-01-01

The critical heat flux look-up table (CHF LUT) is widely used to predict CHF for various applications, including design and safety analysis of nuclear reactors. Using the CHF LUT for round tubes having inside diameters different from the reference 8 mm involves conversion of CHF to 8 mm. Different authors [Becker, K.M., 1965. An Analytical and Experimental Study of Burnout Conditions in Vertical Round Ducts, Aktiebolaget Atomenergie Report AE 177, Sweden; Boltenko, E.A., et al., 1989. Effect of tube diameter on CHF at various two phase flow regimes, Report IPE-1989; Biasi, L., Clerici, G.C., Garriba, S., Sala, R., Tozzi, A., 1967. Studies on Burnout, Part 3, Energia Nucleare, vol. 14, pp. 530-536; Groeneveld, D.C., Cheng, S.C., Doan, T., 1986. AECL-UO critical heat flux look-up table. Heat Transfer Eng., 7, 46-62; Groeneveld et al., 1996; Hall, D.D., Mudawar, I., 2000. Critical heat flux for water flow in tubes - II subcooled CHF correlations. Int. J. Heat Mass Transfer, 43, 2605-2640; Wong, W.C., 1996. Effect of tube diameter on critical heat flux, MaSC dissertation, Ottawa Carleton Institute for Mechanical and Aeronautical Engineering, University of Ottawa] have proposed several types of correlations or factors to describe the diameter effect on CHF. The present work describes the derivation of new diameter correction factor and compares it with several existing prediction methods

Enhancement of pool boiling heat transfer coefficients using carbon nanotubes

International Nuclear Information System (INIS)

Park, Ki Jung; Jung, Dong Soo

2007-01-01

In this study, the effect of carbon nanotubes (CNTs) on nucleate boiling heat transfer is investigated. Three refrigerants of R22, R123, R134a, and water were used as working fluids and 1.0 vol.% of CNTs was added to the working fluids to examine the effect of CNTs. Experimental apparatus was composed of a stainless steel vessel and a plain horizontal tube heated by a cartridge heater. All data were obtained at the pool temperature of 7 .deg. C for all refrigerants and 100 .deg. C for water in the heat flux range of 10∼80 kW/m 2 . Test results showed that CNTs increase nucleate boiling heat transfer coefficients for all fluids. Especially, large enhancement was observed at low heat fluxes of less than 30 kW/m 2 . With increasing heat flux, however, the enhancement was suppressed due to vigorous bubble generation. Fouling on the heat transfer surface was not observed during the course of this study. Optimum quantity and type of CNTs and their dispersion should be examined for their commercial application to enhance nucleate boiling heat transfer in many applications

Electricity from MHD, 1968. Vol. IV. Open-Cycle MHD. Proceedings of a Symposium on Magnetohydrodynamic Electrical Power Generation

International Nuclear Information System (INIS)

1968-01-01

Proceedings of a Symposium on Magnetohydrodynamic Electrical Power Generation held by the IAEA at Warsaw, 24-30 July 1968. The meeting was attended by some 300 participants from 21 countries and three international organizations. In contrast to the Symposium held two years ago, much more emphasis was placed on the economic aspects of using MHD generators in large-scale power generation. Among closed- cycle systems, the prospects of linking an ultra-high-temperature reactor with an MHD generator were explored, and the advantages gained by having a liquid-metal generator as a 'topper' in a conventional steam generating plant were presented. Comments were made about the disproportionate effect of end and boundary conditions in experimental MHD generators on the main plasma parameters, and estimates were made of the interrelationship to be expected in real generators. The estimates will have to await confirmation until results are obtained on large-scale prototype MHD systems. Progress in materials research, in design and construction of auxiliary equipment such as heat exchangers, supercooled magnets (which are- now commercially available), etc., is accompanied by sophisticated ideas of plant design. The Proceedings are complemented by three Round Table Discussions in which chosen experts from various countries discuss the outlook for closed-cycle gas, closed-cycle liquid-metal and open-cycle MHD, and give their views as to the most fruitful course to follow to achieve economic full-scale power generation. Contents: (Vol. I) 1. Closed-Cycle MHD with Gaseous Working Fluids: (a) Diagnostics (3 papers); (b) Steady-state non-equilibrium ionization (8 papers); (c) Transient non-equilibrium ionization (7 papers); (d) Pre-ionization and gas discharge (4 papers); (e) Fields and flow in MHD channels (10 papers); (0 Instabilities (8 papers); (g) Generator design and performance studies (6 papers); (Vol. II) (h) Shock waves (6 papers); (i) Power generation experiments (13 papers

Vol 41 No 2

African Journals Online (AJOL)

Esem

3 Centre for Primary Care Research. Medical Journal of Zambia, Vol. 41, No. 2: 59 - 64 (2014) ... pollutants by inhaling second-hand tobacco smoke are at risk of adverse health ..... To put the measured PM levels into perspective, a. 2.5. 5.

12-EEASA-Vol 22.indd

African Journals Online (AJOL)

jenny

2006-02-22

Feb 22, 2006 ... Southern African Journal of Environmental Education, Vol. .... To this end, a planning conference on environmental .... mathematics, physics, chemistry, biology, geography, agriculture, home economics and human and.

Index to Nuclear Safety. A technical progress review by chronology, permuted title, and author. Vol. 11, No. 1 through Vol. 15, No. 6

International Nuclear Information System (INIS)

Cottrell, W.B.; Klein, A.

1975-04-01

This issue of the Index to Nuclear Safety covers only articles included in Nuclear Safety, Vol. 11, No. 1, through Vol. 15, No. 6. This index is presented in three sections as follows: Chronological List of Articles by Volume; Permuted Title (KWIC) Index; and Author Index. (U.S.)

Economic and Policy Review - Vol 13, No 3 (2007)

African Journals Online (AJOL)

Economic and Policy Review - Vol 13, No 3 (2007). Journal Home > Archives > Vol 13, No 3 ... Snagging the wheel of progress: Corruption, New anti-corruption drive and Nigeria\\'s quest for development. S B Kura ... Book Review: challenges of African growth opportunities, constraints and strategic directions. S I Owualah ...

Zede Journal - Vol 29 (2012)

African Journals Online (AJOL)

Journal Home > Archives > Vol 29 (2012) ... Leakage aware hardware and stochastic power scheduling for smart mobile devices ... Energy efficient topology for Wireless Mesh Networks · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

The thermodynamics of heat- and mass exchange in chemical engineering. Vol. 1. 2. rev. ed.

International Nuclear Information System (INIS)

Matz, G.

1979-01-01

The second and completely revised edition of the approved textbook 'The thermodynamics of heat- and mass exchange in chemical engineering' is devoted to students of technical and natural science disciplines as well as to practicians and scientists, which are confronted with thermodynamical problems of chemical engineering. Starting from the different phases and properties of matter, the first and the second law of thermodynamics are discussed together with many applications. After an introduction of the equilibrium state, the general principle of similarity for heat- and mass exchange is discussed, considering in particular the heat- and mass exchange in the counter flow between two phases. In a final chapter, the heat- and mass exchange between the vapor- and liquid phase is discussed, with special emphasis on problems as evaporation and drying. (orig./HK) [de

Reportaje interactivo acerca del panorama político electoral en Ecuador de 2016 a 2017.

OpenAIRE

Rojas Cajamarca, Juan Carlos

2017-01-01

This study is an interactive report of the 2016 to 2017 electoral panorama in Ecuador, it focuses in building a multimedia product, which would be used to classify the profiles and campaign plans of the different candidates, synthetizing the huge amount of information in existence. For this purpose we have sustained our research in the analysis done from the perspective of political communication, study of its different narratives, and with this we have elaborated a transmedia product utilizi...

Influence of heat treatment on the high temperature oxidation mechanisms of an Fe-TiCN cermet

OpenAIRE

Alvaredo Olmos, Paula; Abajo Clemente, Carolina; Tsipas, Sophia Alexandra; Gordo Odériz, Elena

2014-01-01

In this study, the oxidation behaviour of an iron matrix cermet containing 50 % vol. Ti(C,N) was investigated before and after heat treatment by oxidation tests performed in static air at temperatures between 500 °C and 1000 °C. The oxidation mechanism for this type of composite materials was established and it was found that the heat treated material presents lower mass gain than the as-sintered material at the early stages of the oxidation, due to the volatilization of oxides. The oxidation...

samaru-main-vol 11 2011

African Journals Online (AJOL)

Library _info_Sc_ 1

2004-07-11

Jul 11, 2004 ... Samaru Journal of Information Studies Vol. 11 (1 & 2)2011 ... It is therefore paramount that the library ... source of primary and up to date information, both students and ... entertainment, arts, fashion, law, economy, medicine,.

Vol 12, No 1 (2014)

African Journals Online (AJOL)

Egyptian Journal of Pediatric Allergy and Immunology (The) - Vol 12, No 1 (2014) ... The effect of serum angiotensin II and angiotensin II type 1 receptor gene ... with diabetic ketoacidosis · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

New hybrid nanofluid containing encapsulated paraffin wax and sand nanoparticles in propylene glycol-water mixture: Potential heat transfer fluid for energy management

International Nuclear Information System (INIS)

Manikandan, S.; Rajan, K.S.

2017-01-01

Highlights: • Hybrid nanofluid containing sand nanoparticles & encapsulated paraffin wax prepared. • Specific heat of hybrid nanofluid 9% greater than that of PG-water mixture. • Specific heat & thermal conductivity enhanced at optimum paraffin wax concentration. • Hybrid nanofluid with 1 wt.% paraffin wax & 1 vol% sand nanoparticles best suited. - Abstract: The reduction in specific heat commonly encountered due to the addition of nanoparticles to a heat transfer fluid such as propylene glycol-water mixture, can be overcome by co-dispersing surfactant-encapsulated paraffin wax, leading to formation of a hybrid nanofluid. Experimental investigations have been carried out on the preparation and evaluation of thermophysical properties of a hybrid nanofluid containing pluronic P-123 encapsulated paraffin wax (70–120 nm diameter, 1–5 wt.%) and sand nanoparticles (1 vol%) in propylene glycol-water mixture. The comparison of results of differential scanning calorimetry of pure paraffin wax and encapsulated paraffin wax revealed encapsulation efficiency of 84.4%. The specific heat of hybrid nanofluids monotonously increased with paraffin wax concentration, with 9.1% enhancement in specific heat for hybrid nanofluid containing 5 wt.% paraffin wax, in comparison to propylene glycol-water mixture. There exists an optimum paraffin wax concentration (1 wt.%) for the hybrid nanofluid at which the combination of various thermophysical properties such as specific heat, thermal conductivity and viscosity are favorable for use as heat transfer fluid. Such a hybrid nanofluid can be used as a substitute for propylene glycol-water mixture in solar thermal systems.

Influence of the Particle Length of Carbon Nanotube for Pool Boiling Critical Heat Flux Enhancement of Nanofluids

International Nuclear Information System (INIS)

Park, Sung Seek; Kim, Yong Hwan; Kim, Nam Jin

2013-01-01

The results of this experiment were that the CHF of the two nanofluids increased along with the volumetric fraction until 0.001 vol%, and the two types of nanofluids are the highest CHF at 0.001 vol%. Also, the results show clearly that the rate of CHF increase of the CM-100 MWCNT nanofluid with longer-length nanoparticles is higher than that of the CM-95 MWNCT nanofluid. These results indicate that the length of carbon nanotube influences the pool boiling CHF of carbon nanotube nanofluid and that long-length MWCNT, as above-noted, offers a superior effect in this regard. Boiling heat transfer is used in a variety of industrial processes and applications, such as refrigeration, power generation, heat exchangers, cooling of high-power electronics components and cooling of nuclear reactors. The critical heat flux (CHF) phenomenon is the thermal limit during a boiling heat transfer phase change; at the CHF point the heat transfer is maximised, followed by a drastic degradation after the CHF point. The consequence is a substantial increase in wall temperature which may result in physical failure phenomenon of heat transfer systems. Therefore, the CHF is important being considered in the cooling device design, such as nuclear reactor and nuclear fuels, steam generators, high-density electronic component, etc. And, CHF enhancement is essential for safety of heat transfer system. Recently, CHF reported increased when applied to the nanofluids, with its high (higher-than-base-fluid) thermal characteristic in the nuclear power plant system. Therefore, in this study, carried out the pool boiling CHF experiments by the particle length using carbon nanotube nanofluids, and the results are compared and analyzed for the CHF enhancement. The pool boiling CHF of experiments of carbon nanotube nanofluids carried out by the length of particles and the various concentrations

Anestesia volátil e monitorização anestésica.

OpenAIRE

Alexandre, Nuno; Costa, Margarida; Mascarenhas, Ramiro

2009-01-01

Os autores apresentam um texto de apoio à disciplina de anestesiologia do curso de Medicina Veterinária .Neste texto são abordadas diversas temáticas da anestesia volátil tais como: equipamentos utilizados em anestesia volátil, farmacologia dos anestésicos voláteis. A monitorização dos pacientes é abordada na vertente mecânica ou intrumental e na componente básica.

Index to Nuclear Safety: a technical progress review by chronology, permuted title, and author. Vol. 11(1)--Vol. 18(6)

Energy Technology Data Exchange (ETDEWEB)

Cottrell, W.B.; Klein, A.

1978-04-11

This index to Nuclear Safety covers articles published in Nuclear Safety, Vol. 11, No. 1 (January-February 1970), through Vol. 18, No. 6 (November-December 1977). It is divided into three sections: a chronological list of articles (including abstracts) followed by a permuted-title (KWIC) index and an author index. Nuclear Safety, a bimonthly technical progress review prepared by the Nuclear Safety Information Center (NSIC), covers all safety aspects of nuclear power reactors and associated facilities. Over 450 technical articles published in Nuclear Safety in the last eight years are listed in this index.

Index to Nuclear Safety: a technical progress review by chronology, permuted title, and author. Vol. 11(1)--Vol. 18(6)

International Nuclear Information System (INIS)

Cottrell, W.B.; Klein, A.

1978-01-01

This index to Nuclear Safety covers articles published in Nuclear Safety, Vol. 11, No. 1 (January-February 1970), through Vol. 18, No. 6 (November-December 1977). It is divided into three sections: a chronological list of articles (including abstracts) followed by a permuted-title (KWIC) index and an author index. Nuclear Safety, a bimonthly technical progress review prepared by the Nuclear Safety Information Center (NSIC), covers all safety aspects of nuclear power reactors and associated facilities. Over 450 technical articles published in Nuclear Safety in the last eight years are listed in this index

Ethiopian Journal of Health Sciences - Vol 28, No 2 (2018)

African Journals Online (AJOL)

Ethiopian Journal of Health Sciences - Vol 28, No 2 (2018). Journal Home > Archives > Vol 28, No 2 (2018). Log in or Register to get access to full text downloads. ... Prevalence of opportunistic intestinal parasites and associated factors among HIV patients while receiving ART at Arba Minch Hospital in southern Ethiopia: a ...

Dynamics of structures '89. Vol. 1 and 2

International Nuclear Information System (INIS)

1989-01-01

The proceedings, comprising 3 volumes published by the Plzen Centre of the Czechoslovak Society for Science and Technology (Vol. 1 and 2) and by Skoda Works in Plzen (Vol. 3), contain 107 papers, out of which 8 fall within the INIS Subject Scope; these deal with problems related to the earthquake resistance of nuclear power plants. Attention is paid to the evaluation of seismic characteristics of nuclear power plant equipment, to the equipment testing and to calculations of its dynamic characteristics under simulated seismic stress. (Z.M.)

Large hadron collider workshop. Proceedings. Vol. 3

International Nuclear Information System (INIS)

Jarlskog, G.; Rein, D.

1990-01-01

The aim of the LHC workshop at Aachen was to discuss the 'discovery potential' of a high-luminosity hadron collider (the Large Hadron Collider) and to define the requirements of the detectors. Of central interest was whether a Higgs particle with mass below 1 TeV could be seen using detectors potentially available within a few years from now. Other topics included supersymmetry, heavy quarks, excited gauge bosons, and exotica in proton-proton collisions, as well as physics to be observed in electron-proton and heavy-ion collisions. A large part of the workshop was devoted to the discussion of instrumental and detector concepts, including simulation, signal processing, data acquisition, tracking, calorimetry, lepton identification and radiation hardness. The workshop began with parallel sessions of working groups on physics and instrumentaiton and continued, in the second half, with plenary talks giving overviews of the LHC project and the SSC, RHIC, and HERA programmes, summaries of the working groups, presentations from industry, and conclusions. Vol. 1 of these proceedings contains the papers presented at the plenary sessions, Vol. 2 the individual contributions to the physics sessions, and Vol. 3 those to the instrumentation sessions. (orig.)

Large hadron collider workshop. Proceedings. Vol. 2

International Nuclear Information System (INIS)

Jarlskog, G.; Rein, D.

1990-01-01

The aim of the LHC workshop at Aachen was to discuss the 'discovery potential' of a high-luminosity hadron collider (the Large Hadron Collider) and to define the requirements of the detectors. Of central interest was whether a Higgs particle with mass below 1 TeV could be seen using detectors potentially available within a few years from now. Other topics included supersymmetry, heavy quarks, excited gauge bosons, and exotica in proton-proton collisions, as well as physics to be observed in electron-proton and heavy-ion collisions. A large part of the workshop was devoted to the discussion of instrumental and detector concepts, including simulation, signal processing, data acquisition, tracking, calorimetry, lepton identification and radiation hardness. The workshop began with parallel sessions of working groups on physics and instrumentation and continued, in the second half, with plenary talks giving overviews of the LHC project and the SSC, RHIC, and HERA programmes, summaries of the working groups, presentations from industry, and conclusions. Vol.1 of these proceedings contains the papers presented at the plenary sessions, Vol.2 the individual contributions to the physics sessions, and Vol.3 those to the instrumentation sessions. (orig.)

Large hadron collider workshop. Proceedings. Vol. 1

International Nuclear Information System (INIS)

Jarlskog, G.; Rein, D.

1990-01-01

The aim of the LCH workshop at Aachen was to discuss the 'discovery potential' of a high-luminosity hadron collider (the Large Hadron Collider) and to define the requirements of the detectors. Of central interest was whether a Higgs particle with mass below 1 TeV could be seen using detectors potentially available within a few years from now. Other topics included supersymmetry, heavy quarks, excited gauge bosons, and exotica in proton-proton collisions, as well as physics to be observed in electron-proton and heavy-ion collisions. A large part of the workshop was devoted to the discussion of instrumental and detector concepts, including simulation, signal processing, data acquisition, tracking, calorimetry, lepton identification and radiation hardness. The workshop began with parallel sessions of working groups on physics and instrumentation and continued, in the second half, with plenary talks giving overviews of the LHC project and the SSC, RHIC, and HERA programmes, summaries of the working groups, presentations from industry, and conclusions. Vol. 1 of these proceedings contains the papers presented at the plenary sessions, Vol. 2 the individual contributions to the physics sessions, and Vol. 3 those to the instrumentation sessions. (orig.)

Errata Resonance, Vol.20, No.12, 2015. Rajaram Nityananda, Sun ...

Indian Academy of Sciences (India)

IAS Admin

Resonance, Vol.20, No.12, 2015. Rajaram Nityananda, Sun, Sky and Clouds: Where Light and Matter Meet. Page 1121: The correct Figure 5 is reproduced below: Resonance, Vol.20, No.11, 2015. Anil Kumar, Felix Bloch (1905–1983). Page 956: Para 1, Line 5, 'also from Zürich' should be read as 'from nearby Bern'.

Information manager-2011-Vol 11

African Journals Online (AJOL)

Library _info_Sc_ 1

The Information Manager Vol. ... extent while carrying out their duties on a daily basis. ... It concluded by admonishing librarians to brace up and keep pace ... Proper training should be given to .... used to information and communication technologies .... proficiency Skills .... analysis of the workplace and implementation of.

Natural convection heat transfer from a horizontal cylinder in liquid sodium. Pt. 2. Generalized correlation for laminar natural convection heat transfer

International Nuclear Information System (INIS)

Hata, K.; Takeuchi, Y.

1999-01-01

For pt.I see ibid., vol.193, p.105-18, 1999. Rigorous numerical solution of natural convection heat transfer, from a horizontal cylinder with uniform surface heat flux or with uniform surface temperature, to liquid sodium was derived by solving the fundamental equations for laminar natural convection heat transfer without the boundary layer approximation. It was made clear that the local and average Nusselt numbers experimentally obtained and reported in part 1 of this paper were described well by the numerical solutions for uniform surface heat fluxes, but that those for uniform surface temperatures could not describe the angular distribution of the local Nusselt numbers and about 10% underpredicted the average Nusselt numbers. Generalized correlation for natural convection heat transfer from a horizontal cylinder with a uniform surface heat flux in liquid metals was presented based on the rigorous theoretical values for a wide range of Rayleigh numbers. It was confirmed that the correlation can describe the authors' and other workers' experimental data on horizontal cylinders in various kinds of liquid metals for a wide range of Rayleigh numbers. Another correlation for a horizontal cylinder with a uniform surface temperature in liquid metals, which may be applicable for special cases such as natural convection heat transfer in a sodium-to-sodium heat exchanger etc. was also presented based on the rigorous theoretical values for a wide range of Rayleigh numbers. These correlations can also describe the rigorous numerical solutions for non-metallic liquids and gases for the Prandtl numbers up to 10. (orig.)

Index to Nuclear Safety. A technical progress review by chronology, permuted title, and author. Vol. 11, No. 1--Vol. 17, No. 6

International Nuclear Information System (INIS)

Cottrell, W.B.; Klein, A.

1977-01-01

This index to Nuclear Safety covers articles in Nuclear Safety Vol. 11, No. 1 (Jan.-Feb. 1970), through Vol. 17, No. 6 (Nov.-Dec. 1976). The index includes a chronological list of articles (including abstract) followed by KWIC and Author Indexes. Nuclear Safety, a bimonthly technical progress review prepared by the Nuclear Safety Information Center, covers all safety aspects of nuclear power reactors and associated facilities. The index lists over 350 technical articles in the last six years of publication

Index to Nuclear Safety. A technical progress review by chronology, permuted title, and author. Vol. 11, No. 1--Vol. 17, No. 6

Energy Technology Data Exchange (ETDEWEB)

Cottrell, W.B.; Klein, A.

1977-02-23

This index to Nuclear Safety covers articles in Nuclear Safety Vol. 11, No. 1 (Jan.-Feb. 1970), through Vol. 17, No. 6 (Nov.-Dec. 1976). The index includes a chronological list of articles (including abstract) followed by KWIC and Author Indexes. Nuclear Safety, a bimonthly technical progress review prepared by the Nuclear Safety Information Center, covers all safety aspects of nuclear power reactors and associated facilities. The index lists over 350 technical articles in the last six years of publication.

Geothermal direct-heat utilization assistance. Quarterly project progress report, October--December 1997

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-01-01

This report summarizes geothermal technical assistance, R and D and technology transfer activities of the Geo-Heat Center at Oregon Institute of Technology for the first quarter of FY-98 (October--December 1997). It describes 216 contacts with parties during this period related to technical assistance with geothermal direct heat projects. Areas dealt with include requests for general information including maps and material for high school debates, and material on geothermal heat pumps, resource and well data, space heating and cooling, greenhouses, aquaculture, equipment, district heating, resorts and spas, industrial applications, electric power and snow melting. Research activities include work on model construction specifications of lineshaft submersible pumps and plate heat exchangers, a comprehensive aquaculture developer package and revisions to the Geothermal Direct Use Engineering and Design Guidebook. Outreach activities include the publication of the Quarterly Bulletin (Vol. 18, No. 4) which was devoted entirely to geothermal activities in South Dakota, dissemination of information mainly through mailings of publications, tours of local geothermal uses, geothermal library acquisition and use, participation in workshops, short courses and technical meetings by the staff, and progress monitor reports on geothermal activities.

NJB VOL.34 Original Lower.cdr

African Journals Online (AJOL)

important sources of renewable biological ... The plantain (Musa paradisiaca) and banana chemicals (Nowak et ... fermentable sugars available for bio-ethanol ..... peels. Afr. J. Biochem. Res. 9(9): 104 - 109. 70. Osho et al./ Nig. J. Biotech. Vol.

Experimental and neoclassical electron heat transport in the LMFP regime for the stellarators W7-A, L-2, and W7-AS

International Nuclear Information System (INIS)

Maassberg, H.; Burhenn, R.; Gasparino, U.; Kuehner, G.; Ringler, H.; Dyabilin, K.S.

1993-01-01

The electron energy balance is analyzed for equivalent low-density electron cyclotron resonance heated (ECRH) discharges with highly peaked central power deposition in the stellarators W7-A [Plasma Phys. Controlled Fusion 28, 43 (1986)], L-2 [Proceedings of the 6th International Conference on Plasma Physics and Controlled Nuclear Fusion Research, Berchtesgaden, 1976 (International Atomic Energy Agency, Vienna, 1977), Vol. 2, p. 115] and W7-AS [Proceedings of the 9th International Conference on Plasma Physics and Controlled Nuclear Fusion Research, Baltimore, 1982 (International Atomic Energy Agency, Vienna, 1983), Vol. 3, p. 141]. Within the long mean-free path (LMFP) collisionality regime in stellarators, the neoclassical electron heat diffusivity χ e can overcome the ''anomalous'' one. The neoclassical transport coefficients are calculated by the DKES code (Drift Kinetic Equation Solver) [Phys. Fluids 29, 2951 (1986); Phys. Fluids B 1, 563 (1989)] for these configurations, and the particle and energy fluxes are estimated based on measured density and temperature profiles

Central African Journal of Medicine - Vol 60, No 9-12 (2016)

African Journals Online (AJOL)

Central African Journal of Medicine - Vol 60, No 9-12 (2016). Journal Home > Archives > Vol 60, No 9-12 (2016). Supplementary Issue. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue ...

The pebble-bed high-temperature reactor as a source of nuclear process heat. Vol. 3

International Nuclear Information System (INIS)

Kugeler, K.; Schulten, R.; Kugeler, M.; Niessen, H.F.; Roeth-Kamat, M.; Hohn, H.; Woike, O.; Germer, J.H.

1974-08-01

The characteristic questions concerning a process heat reactor with high helium outlet temperatures are dealt with in this volume like e.g. fuel element design, corrosion, and fission product release. Furthermore, some possibilities of the technical realization of the hot-gas ducting and intermediate heat exchangers are described. Important parameters for the design of the reactor such as core power density, helium inlet and outlet temperatures, helium pressure and fuel cycle burn-up and conversion and the effect of these on the primary circuit are investigated. The important question regarding which reactor vessel is to be chosen for nuclear process heat plants is discussed with the aid of the integrated and non-integrated concepts using prestressed concrete, cast iron and cast steel. Thereafter, considerations on the safety of the nuclear plant are given. Finally, mention is made of the availability of the nuclear plant and of the status of development of the HTR technology. (orig.) [de

Clinics in Mother and Child Health - Vol 5, No 1 (2008)

African Journals Online (AJOL)

Clinics in Mother and Child Health - Vol 5, No 1 (2008). Journal Home > Archives > Vol 5, No 1 (2008). Special Edition - Congress Abstracts. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue ...

Proceedings of the Seventh Conference of Nuclear Sciences and Applications. Vol.1,2,3

International Nuclear Information System (INIS)

Aly, H.F.

2000-01-01

The publication has been set up as a textbook for nuclear sciences and applications vol.1: (1) radiochemistry; (2) radiation chemistry; (3) isotope production; (4) waste management; vol.2: (1) nuclear and reactor; (2) physics; (3) plasma physics; (4) instrumentation and devices; (5) trace and ultra trace analysis; (6) environmental; vol.3: (1) radiation protection; (2) radiation health hazards; (3) nuclear safety; (4) biology; (5) agriculture

Proceedings of the Seventh Conference of Nuclear Sciences and Applications. Vol.1,2,3

Energy Technology Data Exchange (ETDEWEB)

Aly, H F [ed.

2000-07-01

The publication has been set up as a textbook for nuclear sciences and applications vol.1: (1) radiochemistry; (2) radiation chemistry; (3) isotope production; (4) waste management; vol.2: (1) nuclear and reactor; (2) physics; (3) plasma physics; (4) instrumentation and devices; (5) trace and ultra trace analysis; (6) environmental; vol.3: (1) radiation protection; (2) radiation health hazards; (3) nuclear safety; (4) biology; (5) agriculture.

Proceedings of the second international conference on environmental impact assessment of all economical activities. Vol. 1

International Nuclear Information System (INIS)

1993-01-01

Proceedings of the conference consist of 3 volumes: Vol. 1 - 'Environmental Impact Assessment of all Economical Activities including Industry'; Vol. 2 - 'Air Pollution Control and Prevention'; Vol. 3 - Waste Management and Environmental Problems in Construction Industry'. Out of 32 papers contained in Vol. 1, 2 were inputted to INIS. They deal with models of radionuclide transport in food chains and the use of aerial monitoring in the study of environmental contamination. (Z.S.)

Radiotracers in medical applications, vols 1-2

International Nuclear Information System (INIS)

Rayudu, G.V.S.

1983-01-01

These volumes will serve as a basis for instruction and reference for professionals such as radiopharmaceutical chemists, radiopharmacologists, radiopharmacists, radiobiochemists, and others involved in the medical applications of radiotracers. Vol. I: Topics include radiohalogenated compounds, including radioiodine; Tc-labeled compounds; and in-house prepared radiopharmaceuticals. The charge particle range vs. energy in every element is tabulated for protons for cyclotrons users. Discussions are also provided on nonimaging radiotracer methods; 11 C, 13 N, 15 O, 67 Ga. 111 In, 75 Se, /SUP 123m/ Te compounds; radioactive noble gases; and miscellaneous radiotracers for imaging. Vol. II: Pertinent nuclear science data such as radiation dosimetry, radionuclide production modes, radionuclides for therapy, human experimentation regulations and consent forms, and radiotracer laboratory designs are presented

Z Physics at LEP 1. Vol. 3

International Nuclear Information System (INIS)

Altarelli, G.; Kleiss, R.; Verzegnassi, C.

1989-01-01

The contents of this final report from the Workshop on Z Physics at LEP can be divided into two parts. The first part, comprising Vols. 1 and 2, is a relatively concise but fairly complete handbook on the physics of e + e - annihilation near the Z peak (with normal LEP luminosity and unpolarized beams, appropriate for the first phase of LEP operation). The second part (Vol. 3) is devoted to a review of the existing Monte Carlo event generators for LEP physics. A special effort has been made to co-ordinate the different parts of this report, with the aim of achieving a systematic and balanced review of the subject, rather than having simply a collection of separate contributions. (orig.)

Z physics at LEP 1. Vol. 1

International Nuclear Information System (INIS)

Altarelli, G.; Kleiss, R.; Verzegnassi, C.

1989-01-01

The contents of this final report from the Workshop on Z Physics at LEP can be divided into two parts. The first part, comprising Vols. 1 and 2, is a relatively concise but fairly complete handbook on the physics of e + e - annihilation near the Z peak (with normal LEP luminosity and unpolarized beams, appropriate for the first phase of LEP operation). The second part (Vol. 3) is devoted to a review of the existing Monte Carlo event generators for LEP physics. A special effort has been made to co-ordinate the different parts of this report, with the aim of achieving a systematic and balanced review of the subject, rather than having simply a collection of separate contributions. (orig.)

The pebble-bed high-temperature reactor as a source of nuclear process heat. Vol. 10

International Nuclear Information System (INIS)

Schulten, R.; Kugeler, K.; Kugeler, M.; Niessen, H.F.; Roeth-Kamat, M.; Woike, O.

1974-08-01

The necessary development steps, which have to be taken for the construction of a prototype plant for nuclear process heat, are enumerated. In particular, the work which is involved for the development of the nuclear steam-reforming technique, for the further development of the ball-shaped fuel elements at high gas outlet temperatures and for the reactor components, is described in detail. A brief survey of the needs of development of the IHX (intermediate heat exchanger) is given. An attempt is made to give overall time and cost estimates. (orig.) [de

A finite volume procedure for fluid flow, heat transfer and solid-body stress analysis

KAUST Repository

Jagad, P. I.

2018-04-12

A unified cell-centered unstructured mesh finite volume procedure is presented for fluid flow, heat transfer and solid-body stress analysis. An in-house procedure (A. W. Date, Solution of Transport Equations on Unstructured Meshes with Cell-Centered Colocated Variables. Part I: Discretization, International Journal of Heat and Mass Transfer, vol. 48 (6), 1117-1127, 2005) is extended to include the solid-body stress analysis. The transport terms for a cell-face are evaluated in a structured grid-like manner. The Cartesian gradients at the center of each cell-face are evaluated using the coordinate transformation relations. The accuracy of the procedure is demonstrated by solving several benchmark problems involving different boundary conditions, source terms, and types of loading.

Proceedings of the 1. Arabic conference on chemical applications (Chemia 2). Vol. 2

International Nuclear Information System (INIS)

1997-11-01

The conference of chemical application was held on 1-5 Nov 1997 in Cairo, This vol.2 contains of chemical application on nuclear materials. Studies on these vol.This second volume covers papers presented on the subjects

Proceedings of the second international conference on environmental impact assessment of all economical activities. Vol. 2

International Nuclear Information System (INIS)

1993-01-01

Proceedings of the conference consist of 3 volumes: Vol. 1 - 'Environmental Impact Assessment of all Economical Activities including Industry'; Vol. 2 - 'Air Pollution Control and Prevention'; Vol. 3 - Waste Management and Environmental Problems in Construction Industry'. Out of 32 papers contained in Vol. 2, 4 were inputted to INIS. They deal with nuclear fusion as a potential energy source, with environmental aspects of disposal of ashes from power plants in the Czech Republic, and with land reclamation after mining activities. (Z.S.)

Heat load and deuterium plasma effects on SPS and WSP tungsten

Czech Academy of Sciences Publication Activity Database

Vilémová, Monika; Matějíček, Jiří; Nevrlá, Barbara; Chernyshova, M.; Gasior, P.; Kowalska-Strzeciwilk, E.; Jäger, Aleš

2015-01-01

Roč. 60, č. 2 (2015), s. 275-283 ISSN 0029-5922. [Kudowa Summer School 2014 "Towards Fusion Energy"/12./. Kudowa Zdrój, 09.06.2014-13.06.2014] R&D Projects: GA ČR(CZ) GA14-12837S Institutional support: RVO:61389021 ; RVO:68378271 Keywords : Tungsten * fusion * heat loading * irradiation * bubbles * surface damage Subject RIV: JJ - Other Materials; JJ - Other Materials (FZU-D) Impact factor: 0.546, year: 2015 http://www.nukleonika.pl/www/back/full/vol60_2015/v60n2p275f.pdf

Index to Nuclear Safety. A technical progress review by chronology, permuted title, and author. Vol 11, No. 1 through Vol. 16, No. 6

International Nuclear Information System (INIS)

Cottrell, W.B.; Klein, A.

1976-04-01

This index to Nuclear Safety covers articles in Nuclear Safety Vol. 11, No. 1 (Jan.-Feb. 1970) through Vol. 16, No. 6 (Nov.-Dec. 1975). Included in the index is a chronological list of articles (including abstract) followed by both a KWIC index and an Author Index. Nuclear Safety is a bimonthly technical progress review prepared by the Nuclear Safety Information Center and covers all safety aspects of nuclear power reactors and associated facilities. The index lists over 300 technical articles in the last six years of publication

Index to Nuclear Safety. A technical progress review by chronology, permuted title, and author. Vol 11, No. 1 through Vol. 16, No. 6

Energy Technology Data Exchange (ETDEWEB)

Cottrell, W.B.; Klein, A.

1976-04-01

This index to Nuclear Safety covers articles in Nuclear Safety Vol. 11, No. 1 (Jan.-Feb. 1970) through Vol. 16, No. 6 (Nov.-Dec. 1975). Included in the index is a chronological list of articles (including abstract) followed by both a KWIC index and an Author Index. Nuclear Safety is a bimonthly technical progress review prepared by the Nuclear Safety Information Center and covers all safety aspects of nuclear power reactors and associated facilities. The index lists over 300 technical articles in the last six years of publication.

Proceedings of the second international conference on environmental impact assessment of all economical activities. Vol. 3

International Nuclear Information System (INIS)

1993-01-01

Proceedings of the conference consist of 3 volumes: Vol. 1 - 'Environmental Impact Assessment of all Economical Activities including Industry'; Vol. 2 - 'Air Pollution Control and Prevention'; Vol. 3 - Waste Management and Environmental Problems in Construction Industry'. Out of 39 papers contained in Vol. 3, 3 were inputted to INIS. They deal with the use of portable radioisotope X-ray fluorescence analyzers in the determination of building material contamination by toxic elements, with underground waste repositories and ground water contamination, and the impact of the Temelin nuclear power plant on the hydrosphere and other environmental components. (Z.S.)

AJESMS_ Vol 8 2010 August 15 2011

African Journals Online (AJOL)

Prof. Mereku

2010-08-15

Aug 15, 2010 ... African Journal of Educational Studies in Mathematics and Sciences Vol. 8, 2010 ... environs, a mining area in Wassa West District of Ghana .... This finding is based on autopsy data and on reports showing that blood levels in.

Water SA - Vol 30, No 3 (2004)

African Journals Online (AJOL)

Application of a residential end-use model for estimating cold and hot water demand ... of multistage filtration using different filter media against conventional water ... (Germs et al., 2004), published in the April 2004 (Vol 30 No 2) issue of Water ...

ECONOMICS OF ALEXANDER THE GREAT (15 vols + 4 cdroms) by Gregory Zorzos

OpenAIRE

Gregory Zorzos

2002-01-01

Research contains many ancient texts (Ancient Greek, Hebrews, Hieroglyphs, Assyrian, Sumerian, Babylonian, Latin, etc.). 1. (MICRO-MACRO ECONOMICS OF ALEXANDER THE GREAT (5 vols + cdrom). Microeconomics and macroeconomics of Alexander the Great. Economic theories, feasibilities, economic plannings, general description of the campaign's business plan etc. 2. BANKS OF ALEXANDER THE GREAT (2 vols + cdrom) Describes banking system, economists, financiers, investors, accountants, bookkeepers, etc,...

Heat treatment for improvement in lower temperature mechanical properties of 0.40 pct C-Cr-Mo ultrahigh strength steel

Science.gov (United States)

Tomita, Yoshiyuki; Okabayashi, Kunio

1983-11-01

In the previous paper, it was reported that isothermal heat treatment of a commercial Japanese 0.40 pct C-Ni-Cr-Mo ultrahigh strength steel (AISI 4340 type) at 593 K for a short time followed by water quenching, in which a mixed structure of 25 vol pct lower bainite and 75 vol pct martensite is produced, results in the improvement of low temperature mechanical properties (287 to 123 K). The purpose of this paper is to study whether above new heat treatment will still be effective in commercial practice for improving low temperature mechanical properties of the ultrahigh strength steel when applied to a commercial Japanese 0.40 pct C-Cr-Mo ultrahigh strength steel which is economical because it lacks the expensive nickel component (AISI 4140 type). At and above 203 K this new heat treatment, as compared with the conventional 1133 K direct water quenching treatment, significantly improved the strength, tensile ductility, and notch toughness of the 0.40 pct C-Cr-Mo ultrahigh strength steel. At and above 203 K the new heat treatment also produced superior fracture ductility and notch toughness results at similar strength levels as compared to those obtained by using γ α' repetitive heat treatment for the same steel. However, the new heat treatment remarkably decreased fracture ductility and notch toughness of the 0.40 pct C-Cr-Mo ultrahigh strength steel below 203 K, and thus no significant improvement in the mechanical properties was noticeable as compared with the properties produced by the conventional 1133 K direct water quenching treatment and the γ α' repetitive heat treatment. This contrasts with the fact that the new heat treatment, as compared with the conventional 1133 K direct water quenching treatment and the γ α' repetitive heat treatment, dramatically improved the notch toughness of the 0.40 pct C-Ni-Cr-Mo ultrahigh strength steel, providing a better combination of strength and ductility throughout the 287 to 123 K temperature range. The difference

Actividad antioxidante de compuestos aislados del residuo no-volátil del aceite esencial de naranja.

Directory of Open Access Journals (Sweden)

Vargas-Arispuro, L.

1998-04-01

Full Text Available There has been a growing interest in the food industry and in preventive medicine to search for «natural antioxidants». Therefore the objetive of this study was to evaluate the antioxidant activity of the non-volatile residue of essential orange oil in the oxidation of unrefined and freshly extracted olive oil. Essential orange oil was distilled to obtain a non-volatile residue and fracctionated on a Silica Gel 60 column. The antioxidant activity was determined by measuring peroxide value obtained after heating olive oil at 70 °C for 48 h. Six compounds were isolated and purified, four of these had antioxidant activity, α-tocopherol and three methoxylated flavones were identified using spectroscopic methods. This study confirmed that non-volatile fractions of essential orange oil contain natural antioxidants diferent from α-tocopherol.

Existe un creciente interés en la industria alimentaria y en la medicina preventiva por la búsqueda de «antioxidantes naturales», por lo que nos planteamos evaluar la actividad antioxidante del residuo no volátil del aceite esencial de naranja contra la oxidación del aceite de oliva sin retinar y de reciente extracción. Mediante destilación del aceite esencial de naranja se obtuvo el residuo no-volátil, el cual se fraccionó en columna de silica gel 60. La actividad antioxidante fue medida por el valor de peróxidos producidos por el aceite de oliva al provocar la oxidación por calentamiento a 70 °C durante 48 h. Se aislaron seis compuestos mediante HPLC preparativo de los cuales cuatro tuvieron actividad antioxidante. Usando métodos espectroscópicos se identificaron α-tocoferol y tres flavonas metoxiladas. Con este estudio se confirmó que la fracción no volátil del aceite esencial de naranja contiene antioxidantes naturales diferentes al α-tocoferol.

Gender and Behaviour - Vol 5, No 2 (2007)

African Journals Online (AJOL)

Gender and Behaviour. ... Gender and Behaviour - Vol 5, No 2 (2007) ... Home Type, Age and Gender on The Antisocial Behaviour of Secondary School Students. ... Gender-Wise Comparison on Emotional Intelligence and Marital Satisfaction.

Afican Health Sciences Vol 10 No 4.pmd

African Journals Online (AJOL)

Administrator

African Health Sciences Vol 10 No 4 December 2010. 353. Effect of ... Key words: Rumex steudelii, Antifertility, Folliculogenesis, Endometrium, uterus, ovary, ovarian follicles, corpus luteum,. Rats. ..... first cycle in intrauterine growth-related and.

Preliminary evaluation of rotational Vol-oxidizer for hot cell operation - 5320

International Nuclear Information System (INIS)

Kim, Y.H.; Lee, J.W.; Cho, Y.Z.; Ahn, D.H.; Song, K.C.

2015-01-01

KAERI is developing a mechanical head-end process for pyro-processing. As a piece of the processing equipment, a vol-oxidizer that can handle several tens of kg of HM/batch is under development to supply U 3 O 8 powders to an electrolytic reduction (ER) reactor. To operate a vol-oxidizer in a hot cell, the reactor should be optimized by the mechanical design, and the vol-oxidizer should have a high hull recovery rate. In addition, a vol-oxidizer for hot cell demonstrations that handles the spent fuel of high radiation virulence in a limited space should have a small size and not scatter in its outlet. In this paper, we aim at a preliminary evaluation of a rotational vol-oxidizer for hot cell operation. To evaluate the preliminary situation, we produced a theoretical equation of an optimum reactor size, and verification tests were conducted using an acryl vessel and zircaloy-4 tube according to various weights and lengths. In addition, we predicted the terminal velocity of U 3 O 8 using the terminal velocity of SiO 2 , which will determine the optimum air flux, and through an oxidation experiment, we verified the theory form to detect the existence of U 3 O 8 powder in a discharge filter. In addition, hull separation tests were conducted using a reactor and hulls with a 50 kg HM/batch for the recovery rate of the hulls. The results indicate that we obtained an appropriate air flux so as to not cause U 3 O 8 powder dispersion from using a Stokes equation and density ratio equation prior to the demonstration. The optimum flow and experimental results of the hull separation test have been applied for the design of the demonstration oxidizer, and the operation conditions of the oxidizer were produced. (authors)

Joyo progress report, vol. 8

International Nuclear Information System (INIS)

1983-01-01

Following Joyo Reactor Technology Progress Reports (Vol. 1 to Vol. 7), the name was changed to Joyo Progress Report from this volume, and the activities concerning the fast breeder experimental reactor Joyo as a whole are to be reported as quarterly report. In the fast breeder experimental reactor Joyo, the change to the core for irradiation (MK-2) from the core for breeding (MK-1) was carried out since January, 1982, in order to utilize the reactor as an irradiation facility for the development of fuel and materials. The main work was the construction of the core for irradiation by exchanging 290 fuel elements, and the exchange of upper and lower guide pipes for control rods, the reconstruction of the driving mechanism, the installation of standby neutron detector system, the acceptance and inspection of new fuel, and the transfer of spent fuel between pools were carried out. As scheduled, the core for irradiation attained the initial criticality on November 22, and the works of constructing the core were completed on December 23, 1982. Thereafter, the 100 MW performance test was begun. Various experience and valuable data were obtained in the regular inspection and the maintenance and repair works carried out at the same time, regarding the operation and maintenance of the Joyo facilities. (Kako, I.)

Tanzania Veterinary Journal - Vol 32, No 1 (2017)

African Journals Online (AJOL)

Tanzania Veterinary Journal - Vol 32, No 1 (2017) ... factors for porcine cysticercosis transmission and animal welfare in selected villages in Nyasa, Tanzania ... Thoracic radiographic anatomy in sheep · EMAIL FULL TEXT EMAIL FULL TEXT

African Research Review - Vol 5, No 1 (2011)

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African Research Review - Vol 5, No 1 (2011) .... Gender and Occupational Preferences among Senior High School Students in Cross River State ... Academic Achievement in Physics · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

GLOBAL JOURNAL OF SOCIAL SCIENCES VOL 8, NO

African Journals Online (AJOL)

Ada

GLOBAL JOURNAL OF SOCIAL SCIENCES VOL 8, NO. ... media. From the over fifty tertiary institutions in the country graduates are churned .... few were collected at the contact addresses, ... acquisition is paramount for successful job hunting.

AFRREV STECH, Vol. 3(1) February, 2014

African Journals Online (AJOL)

Toshiba

Indexed African Journals Online: www.ajol.info. AFRREV STECH. An International Journal of Science and Technology. Bahir Dar, Ethiopia. Vol. 3 (1), S/No 6, February, 2014: 1-11. ISSN 2225-8612 (Print) ISSN 2227-5444 (Online). EFFECTS OF DEFORESTATION ON NATURAL. BIO-DIVERSITY IN DELTA NORTH ...

African Health Sciences - Vol 15, No 4 (2015)

African Journals Online (AJOL)

African Health Sciences. ... African Health Sciences - Vol 15, No 4 (2015) .... H Madubedube, Andre P Kengne, Rajiv T Erasmus, Tahir S Pillay, Tandi E ... on lung function and cardiorespiratory fitness in both cigarette and hookah smokers.

Heat Generation Effects on U-Mo/Al through ABAQUS FEM Simulation

Energy Technology Data Exchange (ETDEWEB)

Cho, Taewon; Jeong, Gwan Yoon; Lee, Cheol Min; Sohn Dongseong [Ulsan National Institute of Science and Technology, Ulsan (Korea, Republic of)

2014-05-15

U-Mo/Al dispersion fuels have been considered a most promising candidate for a replacement of Highly Enriched Uranium (HEU) fuel in many research reactors. Coulson developed a FEM model which show the fuel meat realistically and compared the thermal conductivity results of two and three dimensional model. Williams also developed a FEM model which are different from the former in that it use regularly meshed unit cells. He showed a heat generation effects through FEM simulation and the effective thermal conductivity of the fuel with heat generated in the fuel particles is a little lower than that of the fuel with no heat generated. In the current work, the heat generation effects are analyzed and discussed in a wider range of volume fraction with more realistic models by using ABAQUS finite element package. The FEM model is used to determine the effective thermal conductivity of U-Mo/Al and to simulate the heat generation effects in the study. This model reflected the microscopic morphology of the fuel very well by making random distribution particles although the particle shape is considered as sphere. All simulation results show the heat generation effects although the effects are small when the volume fraction of fuels are high. When the particles are surrounded with interaction layers, the heat transfer from the particle to matrix is disturbed by interaction layers due to the low thermal conductivity of interaction layers. However this effects decreases when the sum of the volume fraction of fuels and interaction layers exceeds 40-50 vol% because a great portion of the heat must pass through fuels and interaction layers although the heat is applied on the surface. Therefore particle size and initial particle volume fractions will be the important factors for the heat generation effects when interaction layers grow during irradiations.

African Health Sciences - Vol 13, No 2 (2013)

African Journals Online (AJOL)

African Health Sciences. ... African Health Sciences - Vol 13, No 2 (2013) ... S Musisi, D Akena, E Nakimuli-Mpungu, C Abbo, J Okello, 205-218 .... Alcohol consumption and cigarette smoking pattern among brothelbased female sex workers in ...

PM1 steganographic algorithm using ternary Hamming Code

Directory of Open Access Journals (Sweden)

Kamil Kaczyński

2015-12-01

Full Text Available PM1 algorithm is a modification of well-known LSB steganographic algorithm. It has increased resistance to selected steganalytic attacks and increased embedding efficiency. Due to its uniqueness, PM1 algorithm allows us to use of larger alphabet of symbols, making it possible to further increase steganographic capacity. In this paper, we present the modified PM1 algorithm which utilizies so-called syndrome coding and ternary Hamming code. The modified algorithm has increased embedding efficiency, which means fewer changes introduced to carrier and increased capacity.[b]Keywords[/b]: steganography, linear codes, PM1, LSB, ternary Hamming code

AJESMS Vol 9 2011 October 23 2012 final

African Journals Online (AJOL)

Owner

2011-10-23

Oct 23, 2011 ... African Journal of Educational Studies in Mathematics and Sciences Vol. ... alveolar re-circulation and gravity orientation are key factors in determining the ..... Comp. Biomed. Res. 3, pp 675-689. Pich, J. (1972). Theory of ...

African Research Review - Vol 4, No 4 (2010)

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African Research Review - Vol 4, No 4 (2010) .... Educational Policy and Technological Development in Africa: An X-Ray of Problems and Solutions in the .... Tradition and Art Appreciation: A Boost to Cultural Tourism in Nigeria · EMAIL FREE ...

Physics at LEP2. Vol. 2

International Nuclear Information System (INIS)

Altarelli, G.; Sjoestrand, T.; Zwirner, F.

1995-01-01

This is final report of the Workshop on Physics at LEP2, held at CERN during 1995. The first part of vol. 1 is devoted to aspects of machine physics of particular relevance to experiments, including the energy, luminosity and interaction regions, as well as the measurement of beam energy. The second part of vol. 1 is a relatively concise, but fairly complete, handbook on the physics of e + e - annihilation above the WW threshold and up to √s∼200 GeV. It contains discussions on WW cross-sections and distributions, W mass determination, Standard Model processes, QCD and gamma-gamma physics, as well as aspects of discovery physics, such as Higgs, new particle searches, triple gauge boson couplings and Z'. The second volume contains a review of the existing Monte Carlo generators for LEP2 physics. These include generators for WW physics, QCD and gamma-gamma processes, Bhabha scattering and discovery physics. A special effort was made to co-ordinate the different parts, with a view to achieving a systematic and balanced review of the subject, rather than just publishing a collection of separate contributions. (orig.)

Physics at LEP2. Vol. 1

International Nuclear Information System (INIS)

Altarelli, G.; Sjoestrand, T.; Zwirner, F.

1996-01-01

This is the final report of the Workshop on Physics at LEP2, held at CERN during 1995. The first part of vol. 1 is devoted to aspects of machine physics of particular relevance to experiments, including the energy, luminosity and interaction regions, as well as the measurement of beam energy. The second part of vol. 1 is a relatively concise, but fairly complete, handbook on the physics of e + e - annihilation above the WW threshold and up to √s∼200 GeV. It contains discussions on WW cross-sections and distributions, W mass determination, Standard Model processes, QCD and gamma-gamma physics, as well as aspects of discovery physics, such as Higgs, new particle searches, triple gauge boson couplings and Z'. The second volume contains a review of the existing Monte Carlo generators for LEP2 physics. These include generators for WW physics, QCD and gamma-gamma processes, Bhabha scattering and discovery physics. A special effort was made to co-ordinate the different parts, with a view to achieving a systematic and balanced review of the subject, rather than just publishing a collection of separate contributions. (orig.)

Physics at LEP2. Vol. 2

Energy Technology Data Exchange (ETDEWEB)

Altarelli, G [ed.; Sjoestrand, T [ed.; Zwirner, F [ed.

1995-02-19

This is final report of the Workshop on Physics at LEP2, held at CERN during 1995. The first part of vol. 1 is devoted to aspects of machine physics of particular relevance to experiments, including the energy, luminosity and interaction regions, as well as the measurement of beam energy. The second part of vol. 1 is a relatively concise, but fairly complete, handbook on the physics of e{sup +}e{sup -} annihilation above the WW threshold and up to {radical}s{approx}200 GeV. It contains discussions on WW cross-sections and distributions, W mass determination, Standard Model processes, QCD and gamma-gamma physics, as well as aspects of discovery physics, such as Higgs, new particle searches, triple gauge boson couplings and Z`. The second volume contains a review of the existing Monte Carlo generators for LEP2 physics. These include generators for WW physics, QCD and gamma-gamma processes, Bhabha scattering and discovery physics. A special effort was made to co-ordinate the different parts, with a view to achieving a systematic and balanced review of the subject, rather than just publishing a collection of separate contributions. (orig.).

Afican Health Sciences Vol 9 No 2.pmd

African Journals Online (AJOL)

Administrator

African Health Sciences Vol 9 No 2 June 2009 ... Background:The under five mortality rate (U5MR) is measure of wellbeing and decreasing the U5MR by two .... under three scenarios 1-3. ... Negative indicates increase in childhood mortalities.

Experimental investigation of convective heat transfer augmentation for car radiator using ZnO–water nanofluids

International Nuclear Information System (INIS)

Ali, Hafiz Muhammad; Ali, Hassan; Liaquat, Hassan; Bin Maqsood, Hafiz Talha; Nadir, Malik Ahmed

2015-01-01

New experimental data are reported for water based nanofluids to enhance the heat transfer performance of a car radiator. ZnO nanoparticles have been added into base fluid in different volumetric concentrations (0.01%, 0.08%, 0.2% and 0.3%). The effect of these volumetric concentrations on the heat transfer performance for car radiator is determined experimentally. Fluid flow rate has been varied in a range of 7–11 LPM (liter per minute) (corresponding Reynolds number range was 17,500–27,600). Nanofluids showed heat transfer enhancement compared to the base fluid for all concentrations tested. The best heat transfer enhancement up to 46% was found compared to base fluid at 0.2% volumetric concentration. A further increase in volumetric concentration to 0.3% has shown a decrease in heat transfer enhancement compared to 0.2% volumetric concentration. Fluid inlet temperature was kept in a range of 45–55 °C. An increase in fluid inlet temperature from 45 °C to 55 °C showed increase in heat transfer rate up to 4%. - Highlights: • ZnO–water nanofluids were used for car radiator thermal enhancement. • Heat transfer enhancement up to 46% was achieved comparing pure water. • 0.2% vol. concentration of ZnO found to be optimum for heat transfer. • Heat transfer was found weakly dependant on the fluid inlet temperature

Southern African Business Review - Vol 21, No 1 (2017)

African Journals Online (AJOL)

Southern African Business Review - Vol 21, No 1 (2017) ... Pre-packaged applications in business reorganisations: International principles · EMAIL ... Microcredit supply under Islamic Banking in Khartoum State, Sudan · EMAIL FREE FULL ...

Journal of Applied Sciences and Environmental Management - Vol ...

African Journals Online (AJOL)

Journal of Applied Sciences and Environmental Management. ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING ... Journal of Applied Sciences and Environmental Management - Vol 22, No 5 (2018) .... Growth Performance of Five Bean (Phaseolus spp) Varieties as Influenced by Organic ...

Sugarcane Bagasse Pyrolysis in a Carbon Dioxide Atmosphere with Conventional and Microwave-Assisted Heating

Energy Technology Data Exchange (ETDEWEB)

Lin, Bo-Jhih; Chen, Wei-Hsin, E-mail: weihsinchen@gmail.com [Department of Aeronautics and Astronautics, National Cheng Kung University, Tainan, Taiwan (China)

2015-02-04

Pyrolysis is an important thermochemical method to convert biomass into bio-oil. In this study, the pyrolysis of sugarcane bagasse in a CO{sub 2} atmosphere under conventional and microwave-assisted heating is investigated to achieve CO{sub 2} utilization. In the microwave pyrolysis, charcoal is used as the microwave absorber to aid in pyrolysis reactions. The results indicate that the yields of pyrolysis products are greatly influenced by the heating modes. In the conventional heating, the prime product is bio-oil and its yield is in the range of 51–54 wt%, whereas biochar is the major product in microwave-assisted heating and its yield ranges from 61 to 84 wt%. Two different absorber blending ratios of 0.1 and 0.3 are considered in the microwave pyrolysis. The solid yield decreases when the absorber blending ratio decreases from 0.3 to 0.1, while the gas and liquid yields increase. This is attributed to more energy consumed for bagasse pyrolysis at the lower blending ratio. Hydrogen is produced under the microwave pyrolysis and its concentration is between 2 and 12 vol%. This arises from the fact that the secondary cracking of vapors and the secondary decomposition of biochar in an environment with microwave irradiation is easier than those with conventional heating.

Geothermal direct-heat utilization assistance. Federal Assistance Program quarterly project progress report, April 1--June 30, 1998

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-07-01

This report summarizes geothermal technical assistance, R and D and technology transfer activities of the Geo-Heat Center at Oregon Institute of Technology for the third quarter of FY98 (April--June, 1998). It describes 231 contacts with parties during this period related to technical assistance with geothermal direct heat projects. Areas dealt with included requests for general information including material for high school and university students, and material on geothermal heat pumps, resource and well data, spacing heating and cooling, greenhouses, aquaculture, equipment, district heating, resorts and spas, industrial applications, snow melting and electric power. Research activities include work on model construction specifications for line shaft submersible pumps and plate heat exchangers, and a comprehensive aquaculture developers package. A brochure on Geothermal Energy in Klamath County was developed for state and local tourism use. Outreach activities include the publication of the Quarterly Bulletin (Vol. 19, No. 2) with articles on research at the Geo-Heat Center, sustainability of geothermal resources, injection well drilling in Boise, ID and a greenhouse project in the Azores. Other outreach activities include dissemination of information mainly through mailings of publications, tours of local geothermal uses, geothermal library acquisitions and use, participation in workshops, short courses and technical meetings by the staff, and progress monitor reports on geothermal activities.

AJESMS_ Vol 8 2010 August 15 2011

African Journals Online (AJOL)

Prof. Mereku

2010-08-15

Aug 15, 2010 ... African Journal of Educational Studies in Mathematics and Sciences Vol. ... girls from two Senior High Schools in Accra, the capital of Ghana in West Africa. .... On the face of it, the Brazilian and Swedish children might seem to have the ... The two profile dimensions that have been specified for teaching, ...

Wind tunnel evaluation of Hi-Vol TSP effectiveness data

Data.gov (United States)

U.S. Environmental Protection Agency — Wind tunnel evaluation of EPA's Hi-Vol TSP sampler for sampling effectiveness with regards to aerodynamic particle diameter (5 to 35 microns), wind speed (2, 8, 24...

Journal of Applied Sciences and Environmental Management - Vol ...

African Journals Online (AJOL)

Journal of Applied Sciences and Environmental Management. ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING ... Journal of Applied Sciences and Environmental Management - Vol 22, No 4 (2018) ... Evaluating the effect of mobility speed on the performance of three handover algorithms in ...

Shostakovich: The Orchestral Songs Vol. 2 / Michael Tanner

Index Scriptorium Estoniae

Tanner, Michael

1996-01-01

Uuest heliplaadist "Shostakovich: The Orchestral Songs Vol. 2: Six Romances on texts by Japanese poets, Op. 21. Six Poems on Marina Tsvetayeva, Op. 143. Suite on Verses of Michelangelo, Op. 145. Gothenburg Symphony Orchestra, Neeme Järvi". DG 447 085-2GH (71 minutes:DDD)

African Journal of Biotechnology - Vol 14, No 18 (2015)

African Journals Online (AJOL)

African Journal of Biotechnology - Vol 14, No 18 (2015). Journal Home ... Isolation of microalgae species from arid environments and evaluation of their potentials for biodiesel production · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

Jolivet: Complete Flute Music, Vol. 2 / Guy S. Rickards

Index Scriptorium Estoniae

Rickards, Guy S.

1996-01-01

Uuest heliplaadist "Jolivet: Complete Flute Music, Vol. 2. Kroumata Percussion Ensemble, Tapiola Sinfonietta, Paavo Järvi". BIS CD 739 (64 minutes: DDD). Item marked from CD630 (6/94), CD272, remainder new to UK

Browse Title Index

African Journals Online (AJOL)

Items 1 - 50 of 226 ... Vol 16 (1999), Analysis of combined heat and mass transfer of water- Vapor in a cylinderical zeolite adsorber, Abstract PDF. A Assefa. Vol 16 (1999), Analysis of combined heat and mass transfer of water-vapor in a cylinderical zeolite adsorber, Abstract PDF. A Assefa. Vol 11 (1994), Analysis of Concrete ...

African Journal of Clinical and Experimental Microbiology - Vol 5, No ...

African Journals Online (AJOL)

African Journal of Clinical and Experimental Microbiology - Vol 5, No 1 (2004) ... ASYMPTOMATIC SIGNIFICANT BACTERIURIA AMONG PREGNANT WOMEN IN ... TO PARASITISM AND THE IMPLICATION ON TREATMENT APPROACH ...

Perception and acceptance of technological risks. Vol. 3

Energy Technology Data Exchange (ETDEWEB)

Renn, O

1981-01-01

Vol. 3 discusses the problem of attitudes towards nuclear power. Data are compiled for five communities in North-Rhine Westphalia with nuclear facilities and the control community of Kerpen, which has no nuclear power plant. At the same time, the empirical and theoretical investigations are comprehensively evaluated.

Southern African Journal of Environmental Education - Vol 8 (1988)

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Southern African Journal of Environmental Education - Vol 8 (1988) ... An interaction of archaeology with school history in a museum education context ... The child in the outdoor classroom · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

Research in Hospitality Management - Vol 5, No 2 (2015)

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Research in Hospitality Management - Vol 5, No 2 (2015) ... Hotel quality in the European Capital of Culture: Leeuwarden 2018 · EMAIL FREE FULL ... Consumer patronage and willingness-to-pay at different levels of restaurant attributes: A ...

Effect of heat absorbing powder addition on cell morphology of porous titanium composite manufactured by reactive precursor method

International Nuclear Information System (INIS)

Kobashi, Makoto; Kamiya, Yoshinori; Kanetake, Naoyuki

2012-01-01

Open-cell structured porous titanium/ceramics composite was synthesized by a reactive precursor method using titanium and boron carbide (B 4 C) as reactant powders. Pore morphology was controlled by adding heat absorbing powder (titanium diboride: TiB 2 ) in the Ti+B 4 C blended powder. The effects of molar blending ratio of titanium and B 4 C and the amount of heat absorbing powder addition on the cell morphology (either open or closed) were investigated. Fine and homogeneous open-cell structure was achieved by adding appropriate amount of heat absorbing agent powder (>15 vol%), and the relative density of the specimen after the reaction became closer to that of the precursor by increasing TiB 2 volume fraction. When the volume fraction of TiB 2 addition was 20%, the open-cell fraction was maintained as 1.0 regardless of the relative density of the precursor.

South African Journal of Higher Education - Vol 19 (2005)

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South African Journal of Higher Education - Vol 19 (2005) ... The 'idea of engagement' and 'the African University in the 21st Century': Some ... The challenges of knowledge production by researchers in Public Administration, a South African ...

Mizan Law Review - Vol 5, No 2 (2011)

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Mizan Law Review - Vol 5, No 2 (2011) ... Ethiopian Law of International Carriage by Air: An Overview · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT ... Comment: Overview of the Core Changes in the New Ethiopian Urban Land Leasehold Proclamation · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

(JASR) Vol. 12, No. 2, 2012 DEPLETING FOREST RESOURCES

African Journals Online (AJOL)

HP

deteriorating forest resources of Nigeria and its impact on climate change. Key words: Forest Resources, ... Mangrove Forest. Sub Total. 905,930 .... South America” Global Biogeographical Cycle vol 9, pp 329-350. Miller, K. R., Reid, W. V., ...

Pan African Medical Journal - Vol 16, No 1 (2014)

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Pan African Medical Journal - Vol 16, No 1 (2014) .... Cancer incidence in Morocco: report from Casablanca registry 2005-2007 · EMAIL FREE FULL .... Maladie de Leo-Buerger faisant suite à une intoxication au cannabis · EMAIL FREE FULL ...

African Heath Sciences Vol 8 No 1.p65

African Journals Online (AJOL)

Harriet

African Health Sciences Vol 8 No 1 March 2008. 36 ... Objective:To highlight difficulties in the diagnosis and management of non-traumatic perforation of small bowel. Material and ..... of three operations for typhoid perforation. Br J Surg. 1997;.

Schostakowitsch. Orchesterlieder (Vol. 2), Neeme Järvi / Werner Pfister

Index Scriptorium Estoniae

Pfister, Werner

1996-01-01

Uuest heliplaadist "Schostakowitsch. Orchesterlieder (Vol. 2): Sechs Romanzen op. 21, Sechs Gedichte op. 143a, Suite auf Verse von Michelangelo Buonarroti op. 145a. Göteborger Sinfoniker, Neeme Järvi". DG CD 447 085-2 (WD: 71'06") DDD

Nigerian Journal of Chemical Research 29 Vol. 15, 2010 ...

African Journals Online (AJOL)

Hp

Nigerian Journal of Chemical Research. 29. Vol. 15, 2010. Antibacterial & Antifungal Studies On Some Coordination Compound Of Metals. With Ampicillin. Pranay Guru. Department of Engineering Chemistry, People's College of Research & Technology, Bhopal. (M. P.) India, email:pranayguru@rediffmail.com. ABSTRACT.

African Journal of Biotechnology - Vol 12, No 21 (2013)

African Journals Online (AJOL)

African Journal of Biotechnology - Vol 12, No 21 (2013) ... Studies of the genetics of inheritance of stem rust resistance in bread wheat · EMAIL FREE .... Evaluation of the effect of ginger modified cassava starch as thickener in the formulation of ...

Cross sections for atomic processes, vol. 2

International Nuclear Information System (INIS)

Takayanagi, Kazuo; Suzuki, Hiroshi; Otani, Shunsuke

1977-09-01

This data collection book contains the data on all processes involving hydrogen and helium isotopes, their ions, electrons and photons, collected systematically and comprehensively, and is compiled subsequently to Vol. 1 as one of the works of the data collection study group in the Institute of Plasma Physics, Nagoya University, Japan. The items of the contents will include energy level, multiplicately excited state, radiation process, electron collision, ionic collision, recombination, collision of neutral atoms, colliding process involving molecules, and other processes. However, the first edition this time contains energy level, radiation process, electron collision and ionic collision, and the data on remaining items are now under collection. Though some criticisms have been heard about Vol. 1, the authors consider that such comprehensive collection based on systematic classification is the foundation of making a generalized data bank expected to become necessary in future. Thus the data collection book includes all relevant processes, and records the experimental data and theoretically calculated results in principle without modification by selecting them systematically. This year, investigation on data evaluation is taken up also as one of the tasks of the study group. (Wakatsuki, Y.)

Experimental study of overall heat transfer coefficient in the application of dilute nanofluids in the car radiator

International Nuclear Information System (INIS)

Peyghambarzadeh, S.M.; Hashemabadi, S.H.; Naraki, M.; Vermahmoudi, Y.

2013-01-01

Heat transfer of coolant flow through the automobile radiators is of great importance for the optimization of fuel consumption. In this study, the heat transfer performance of the automobile radiator is evaluated experimentally by calculating the overall heat transfer coefficient (U) according to the conventional ε-NTU technique. Copper oxide (CuO) and Iron oxide (Fe 2 O 3 ) nanoparticles are added to the water at three concentrations 0.15, 0.4, and 0.65 vol.% with considering the best pH for longer stability. In these experiments, the liquid side Reynolds number is varied in the range of 50–1000 and the inlet liquid to the radiator has a constant temperature which is changed at 50, 65 and 80 °C. The ambient air for cooling of the hot liquid is used at constant temperature and the air Reynolds number is varied between 500 and 700. However, the effects of these variables on the overall heat transfer coefficient are deeply investigated. Results demonstrate that both nanofluids show greater overall heat transfer coefficient in comparison with water up to 9%. Furthermore, increasing the nanoparticle concentration, air velocity, and nanofluid velocity enhances the overall heat transfer coefficient. In contrast, increasing the nanofluid inlet temperature, lower overall heat transfer coefficient was recorded. -- Highlights: ► Overall heat transfer coefficient in the car radiator measured experimentally. ► Nanofluids showed greater heat transfer performance comparing with water. ► Increasing liquid and air Re increases the overall heat transfer coefficient. ► Increasing the inlet liquid temperature decreases the overall heat transfer coefficient

51. Meeting of the Chemical Societies: Almanac of Contributions, Vol. Program, 1, 2, 3, 4 Molecular Models (Workshop)

International Nuclear Information System (INIS)

Uher, M.; Benes, P.; Carsky, J.; Ctrnactova, H.; Fecenko, J.; Fellner, P.; Hodul, P.; Koprda, V.; Kratochvil, B.; Krkoska, P.; Kuruc, J.; Lehotay, J.; Matousek, J.; Milichovsky, P.; Omastova, M.; Petrus, L. jr.; Petrus, L. sr.; Schwendt, P.; Silny, P.; Sevcik, P.; Toma, S.; Uherova, R.; Zachar, P.

1999-09-01

The publication has been set up as a abstracts of the meeting dealing with different chemical problems. The book (Vol. 1) consists of the sections: All-plenary lectures (9 papers); (D) History of the chemistry (14); (K) Didactics of chemistry (32); The book (Vol. 2) consists of the sections: (A) Analytical chemistry (48); (B) Inorganic chemistry (75); (C) Physical chemistry (27); (F) Nuclear chemistry and radioecology (12); (L) Environmental chemistry and toxicology (33); (M) Agricultural chemistry (20). The book (Vol. 3) consists of the sections: (E) Wood, pulp, paper (15); (G) Macromolecular chemistry (42); (H) Organic chemistry, bio-organic chemistry and pharmaceutical chemistry (96); (I) Food chemistry and biochemistry (34); (J) Textile, fibres and foil materials (9). The book (Vol. 4) consists of the workshop Molecular models (3 papers)

Subcooled flow boiling heat transfer of dilute alumina, zinc oxide, and diamond nanofluids at atmospheric pressure

International Nuclear Information System (INIS)

Kim, Sung Joong; McKrell, Tom; Buongiorno, Jacopo; Hu Linwen

2010-01-01

A nanofluid is a colloidal suspension of nano-scale particles in water, or other base fluids. Previous pool boiling studies have shown that nanofluids can improve the critical heat flux (CHF) by as much as 200%. In a previous paper, we reported on subcooled flow boiling CHF experiments with low concentrations of alumina, zinc oxide, and diamond nanoparticles in water (≤0.1% by volume) at atmospheric pressure, which revealed a substantial CHF enhancement (∼40-50%) at the highest mass flux (G = 2500 kg/m 2 s) and concentration (0.1 vol.%) for all nanoparticle materials (). In this paper, we focus on the flow boiling heat transfer coefficient data collected in the same tests. It was found that for comparable test conditions the values of the nanofluid and water heat transfer coefficient are similar (within ±20%). The heat transfer coefficient increased with mass flux and heat flux for water and nanofluids alike, as expected in flow boiling. A confocal microscopy-based examination of the test section revealed that nanoparticle deposition on the boiling surface occurred during nanofluid boiling. Such deposition changes the number of micro-cavities on the surface, but also changes the surface wettability. A simple model was used to estimate the ensuing nucleation site density changes, but no definitive correlation between the nucleation site density and the heat transfer coefficient data could be found.

Ghana Medical Journal - Vol 47, No 2 (2013)

African Journals Online (AJOL)

Ghana Medical Journal - Vol 47, No 2 (2013). Journal Home > Archives ... DOWNLOAD FULL TEXT. AB Olokoba, W Gashau, S Bwala, A Adamu, FK Salawu, 79-81 ... DOWNLOAD FULL TEXT. EY Bonney, NA Addo, NAA Ntim, F Addo-Yobo, P Bondzie, KE Aryee, J Barnor, J brandful, V Bekoe, SA Ohene, W Ampofo, 82-86 ...

Afican Health Sciences Vol 10 No 1.pmd

African Journals Online (AJOL)

Administrator

African Health Sciences Vol 10 No 1 March 2010. 89. Rethinking ... There is a worsening scarcity of Human Resource for ... This is not in any way lowering standards of oncologic diagnosis but filling the otherwise ... for health ratios stand at 0.8 health workers per 1000 ... cancer occurs 10-15years earlier in black women.

Enthalpy relaxation in the cooling/heating cycles of polypropylene/organosilica nanocomposites

International Nuclear Information System (INIS)

Privalko, V.P.; Dinzhos, R.V.; Privalko, E.G.

2005-01-01

Non-isothermally crystallized samples of the neat isotactic polypropylene homopolymer (PP-0) and of a series of nanocomposites (PNC) containing up to 4.68 vol.% of organosilica were characterized by wide-angle and small-angle X-ray diffraction and by the standard DSC, while their melting behavior was studied in the temperature-modulated DSC mode at three underlying heating rates and five modulation frequencies. It was established that the lamellar morphology of PP remained essentially unchanged, whatever the previous cooling rate and/or the organoclay content. The patterns of melting endotherms in both the neat PP sample and the PNC could be semi-quantitatively characterized by a simple Debye model with a single, temperature- and underlying heating rate-dependent characteristic time. The mechanisms of structural rearrangements in the melting intervals of the neat PP sample and the PNC were basically similar; however, the spatial scale of such rearrangements in the latter samples was significantly reduced due to severe steric constraints on the PP chain mobility in the melt state from the infinite cluster of nanoparticles

South African Medical Journal - Vol 88, No 3 (1998)

African Journals Online (AJOL)

Tuberculosis and anorexia nervosa · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. Christopher Paul Szabo, 275-276. Books Advances in Pediatric Pulmonology. Pediatric and Adolescent Medicine Vol. 7 · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

International Journal of Development and Policy Studies - Vol 2, No ...

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International Journal of Development and Policy Studies - Vol 2, No 1 (2006) .... Locating oppressive use of language: a study of linguistic violence on nigerian ... trafficking - poverty link based on urban development and planning process ...

African Journal of Clinical and Experimental Microbiology - Vol 5, No ...

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African Journal of Clinical and Experimental Microbiology - Vol 5, No 3 (2004) ... In Peripheral Leukocyte And Body Fluids Of Onchocerciasis Patients Treated With ... A Study Of Asymptomatic Bacteriuria In Pregnancy In Ile - Ife, Southwestern ...

African Journal of Chemical Education - Vol 7, No 1 (2017)

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African Journal of Chemical Education - Vol 7, No 1 (2017). Journal Home ... Hybridization and molecular geometry: A number game · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD ... AJOL African Journals Online. HOW TO ...

Afican Health Sciences Vol 9 No 1.pmd

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Administrator

African Health Sciences Vol 9 No 1 March 2009. 41 compounds isolated from the extracts can be applied as weed killers and have been tested on the water hyacinth .... dispensing serial dilutions of the test extract, concentrations ranging from 5.0 mg/ml to 50.0 mg/ ml. McFarland No.1 standard was used in the preparation ...

International Journal of Health Research - Vol 2, No 4 (2009)

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International Journal of Health Research - Vol 2, No 4 (2009) ... Psychosocial characteristics of patients admitted to a drug rehabilitation unit in Nigeria · EMAIL ... Hepatoprotective and antioxidant activities of fruit pulp of limonia acidissima linn ...

West African Journal of Industrial and Academic Research - Vol 4 ...

African Journals Online (AJOL)

West African Journal of Industrial and Academic Research - Vol 4, No 1 (2012) ... Open Access DOWNLOAD FULL TEXT Subscription or Fee Access ... on Gas Turbine Engine Data · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

Radiative heat transfer in coal-fired furnaces and oxycoal retrofit considerations

Energy Technology Data Exchange (ETDEWEB)

Erfurth, Jens

2012-07-01

combustion was retained. Heat transfer in the convective section was investigated for all cases based on theoretical derivations and the results of the CFD simulations. The key findings are that - For the given boiler and fuel, the oxygen concentrations at the burners leading to similar flame temperatures as in air combustion are 27 vol.-% in wet recycling and 30 vol.-% in dry recycling. - For the given boiler and fuel, a retrofit is possible for both wet and dry recycling as far as heat transfer (live steam parameters and mass flow) and the furnace exit temperature are concerned. - For the given boiler and fuel, a change of the burner geometry, but not of the boiler geometry will be required to enable retrofit. The models and methodology laid out in this work can be used to investigate heat transfer in air and oxycoal combustion for arbitrary fuels and boiler geometries. (orig.)

Use of nuclear process heat from pebble bed high temperature reactors to obtain oil by tertiary recovery methods. Final report. Vol. 2

International Nuclear Information System (INIS)

Jaeger, H.; Hermges, H.; Kammel, R.; Kugeler, K.; Phlippen, P.W.; Scheuch, H.; Schmidt, F.; Schmidtlein, P.; Schreiner, P.

1988-01-01

Volume II of this report examines: 1. The use of nuclear process heat in the further processing of crude oil (refinery processes, heat coupling, steam reforming helium-heated pipe furnace), 2. Analyses for process questions, 3. Questions of economy, 4. Environmental aspects, 5. Work on underground methanisation. (RB) [de

Journal of Business Research - Vol 6, No 1-2 (2012)

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Journal of Business Research - Vol 6, No 1-2 (2012) ... Economic Cost of Breast Cancer in Ghana: The Komfo Anokye Teaching Hospital ... Capital Adequacy and the Performance of Ghanaian Banks · EMAIL FULL TEXT EMAIL FULL TEXT

West African Journal of Industrial and Academic Research - Vol 17 ...

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West African Journal of Industrial and Academic Research - Vol 17, No 1 (2017) ... Open Access DOWNLOAD FULL TEXT Subscription or Fee Access ... The effect of electricity and gas losses on Nigeria`s Gross Domestic Product · EMAIL ...

Studies in Gender and Development in Africa - Vol 2 (2008)

African Journals Online (AJOL)

Studies in Gender and Development in Africa - Vol 2 (2008) ... I don't love my husband” Advice Columns as Teaching Resource for Gender and Sexuality: Experiences from the University of Cape Coast, Ghana ... Current Issue Atom logo

African Journal for Physical Activity and Health Sciences - Vol 21 ...

African Journals Online (AJOL)

African Journal for Physical Activity and Health Sciences - Vol 21, No 3 (2015) ... Factors Influencing the Health of Men in Polygynous Relationship · EMAIL FULL ... Views of HIV Positive Pregnant Women on Accessibility of the Prevention of ...

Journal of Community Medicine and Primary Health Care - Vol 23 ...

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Journal of Community Medicine and Primary Health Care - Vol 23, No 1-2 (2011) ... The Nigerian National Health Bill 2011: Delay of Presidential Assent to an Act: ... Knowledge And Practice of Occupational Safety Among Quarry Workers in A ...

Nigerian Journal of Chemical Research Vol. 20, 2015 39 Seasonal ...

African Journals Online (AJOL)

Dr M Waziri

Vol. 20, 2015. 39. Seasonal Variations in Physicochemical Properties of Water, Sediment and Fish of ... The levels of some physicochemical parameters in the dam water were determined in wet and dry seasons .... Water, Waste and Health in ...

Rhodium. Suppl. Vol. B1

International Nuclear Information System (INIS)

Griffith, W.P.; Jehn, H.; McCleverty, J.A.; Raub, C.J.; Robinson, S.D.

1982-01-01

The present rhodium vol. B1 is concerned largely with linary compounds and coordination complexes of this important metal, which is used either alone or in alloy form for fabrication of other materials or for heterogeneous catalysis. In first two chapters are devoted for hydrides, oxides, ternary and quaternary oxorhodates. Third chapter is on different type of complexes with nitrogen. From chapter four to seven is on halogen complexes with this metal. Next chapters are on sulphides, sulphoxide and sulphito complexes, sulphates and sulphato complexes, selenides and tellurides, borides, borane complexes, carbides, carbonato, cyno, fulminato and thiocyanato complexes. Finally, silicide, phosphides, phosphito and arsenides are treated over here. (AB)

Fabrication and characterization of microstructure of stainless steel matrix composites containing up to 25 vol% NbC

Energy Technology Data Exchange (ETDEWEB)

Kan, Wen Hao, E-mail: wkan6795@uni.sydney.edu.au [School of Civil Engineering, The University of Sydney, NSW 2006 (Australia); Ye, Zi Jie; Zhu, Yue [School of Civil Engineering, The University of Sydney, NSW 2006 (Australia); Bhatia, Vijay Kumar [School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, NSW 2006 (Australia); Australian Centre for Microscopy and Microanalysis, The University of Sydney, NSW 2006 (Australia); Dolman, Kevin; Lucey, Timothy; Tang, Xinhu [Weir Minerals Australia, Artarmon, NSW 2064 (Australia); Proust, Gwénaëlle [School of Civil Engineering, The University of Sydney, NSW 2006 (Australia); Cairney, Julie [School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, NSW 2006 (Australia); Australian Centre for Microscopy and Microanalysis, The University of Sydney, NSW 2006 (Australia)

2016-09-15

AISI 440 stainless steels reinforced with various volume fractions of niobium carbide (NbC) particles of up to 25 vol% were fabricated in-situ using an argon arc furnace and then heat-treated to produce a martensitic matrix. Optical and scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and electron back-scatter diffraction (EBSD) techniques were used to analyze the microstructure, phases and composition of these composites. Interestingly, it was found that Chinese-script NbC could nucleate on existing primary NbC particles creating NbC clusters with complex microstructures. Additionally, hardness tests were used to evaluate viability in mining and mineral processing applications. The increase in NbC content resulted in an overall increase in the hardness of the composites while causing a marginal decrease in the amount of Cr in solid solution with the matrix, which could be a concern for corrosion resistance. The latter was due to the fact that the NbC lattice could dissolve a minor amount of Cr. Thermodynamic simulations also attributed this to a slight increase in M{sub 7}C{sub 3} precipitation. Nonetheless, these novel composites show great promise for applications in wear and corrosive environments. - Highlights: •Stainless steels reinforced with NbC particles of up to 25 vol% were fabricated. •NbC was formed in-situ in the steels using an arc melter. •Martensitic transformation of the matrix of each sample was achieved. •NbC reinforcements increased the bulk hardness values of the steels. •Dissolved Cr in the matrix of each sample was sufficient for passivity in theory.

Journal of EEA, Vol. 30, 2013 SIEVE TRAY EFFICIENCY USING ...

African Journals Online (AJOL)

dell

Journal of EEA, Vol. 30, 2013. SIEVE TRAY EFFICIENCY USING CFD MODELING AND SIMULATION ... ABSTRACT. In this work, computational fluid dynamics (CFD) .... per unit volume, MG is the molecular weight of the gas/vapor, kL and kG ...

Development of dispersion-strengthened XD (trademark) Cu alloys for high heat-flux applications

Science.gov (United States)

Kumar, K. Sharvan

1993-01-01

In a previous effort sponsored by NASA LeRC, the XD(trademark) process was used to produce ZrB2 particulate reinforcements in Cu and the resulting extruded material was microstructurally characterized and evaluated in tension over a range of temperatures. A problem that was encountered in that study was microstructural inhomogeneity resulting from the frequent presence of 'ZrB2 agglomerates' that were several microns in size. The presence of these agglomerates was attributed to improper mixing of powders in the green compact used in the XD process for elemental boron powder segregation. In this program, several milling parameters were examined in an effort to optimize this processing step; two levels of ZrB2 reinforcements were considered (7 vol. percent and 15 vol. percent). Microstructures of the reacted powder mass were examined to verify the absence of these agglomerates. Larger bathes of powder were then mixed, reacted, machined to size, canned, and extruded. The microstructure and tensile properties of these extrusions were examined, and the measured properties were correlated with the observed microstructure. Large unreacted or partially reacted Zr particles were present. These particles affected the mechanical properties deleteriously, and their presence is attributed to insufficient heat of reaction during XD synthesis. Alternate processing routes are recommended.

South African Journal of Education - Vol 28, No 4 (2008)

African Journals Online (AJOL)

South African Journal of Education - Vol 28, No 4 (2008) ... in Italian high-school prospective mathematics and physics teachers · EMAIL FREE FULL TEXT ... Critical thinking: are the ideals of OBE failing us or are we failing the ideals of OBE?

South African Journal of Education - Vol 31, No 1 (2011)

African Journals Online (AJOL)

South African Journal of Education - Vol 31, No 1 (2011) ... How an analysis of reviewers' reports can enhance the quality of submissions to a journal of education ... Doctoral learning: a case for a cohort model of supervision and support ...

African Journal of Finance and Management - Vol 8, No 2 (2000)

African Journals Online (AJOL)

African Journal of Finance and Management - Vol 8, No 2 (2000) ... Effects of Mergers and Acquisitions to Shareholders' Wealth: Evidence from the United Kingdom. ... Matching Managerial Skills and Behaviour with Business Strategy - ...

Sophia: An African Journal of Philosophy - Vol 10, No 2 (2008)

African Journals Online (AJOL)

Sophia: An African Journal of Philosophy - Vol 10, No 2 (2008) ... Spiritual intelligence (SQ), leadership and good governance: A treatise ... Traditional religion of Ogbaland: Distinguishing characteristics · EMAIL FULL TEXT EMAIL FULL TEXT

Global Journal of Medical Sciences - Vol 10, No 1-2 (2011)

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Global Journal of Medical Sciences - Vol 10, No 1-2 (2011) ... Implications for Global Standards to Promote International Collaboration and Advanced ... Clinical Nursing Research: A Tool for Professional Development · EMAIL FREE FULL ...

Single bubble dynamic behavior in AL{sub 2}O{sub 3}/H{sub 2}O nanofluid on downward-facing heating surface

Energy Technology Data Exchange (ETDEWEB)

Wang, Yun; Wu, Junmei [State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Nuclear Science and Technology, Xi' an Jiaotong University, Xi' an (China)

2016-08-15

After a severe accident to the nuclear reactor, the in-vessel retention strategy is a key way to prevent the leakage of radioactive material. Nanofluid is a steady suspension used to improve heat-transfer characteristics of working fluids, formed by adding solid particles with diameters below 100 nm to the base fluids, and its thermal physical properties and heat-transfer characteristics are much different from the conventional working fluids. Thus, nanofluids with appropriate nanoparticle type and volume concentration can enhance the heat-transfer process. In this study, the moving particle semi-implicit method-meshless advection using flow-directional local grid method is used to simulate the bubble growth, departure, and sliding on the downward-facing heating surface in pure water and nanofluid (1.0 vol.% Al2O3/H2O) flow boiling processes; additionally, the bubble critical departure angle and sliding characteristics and their influence are also investigated. The results indicate that the bubble in nanofluid departs from the heating surface more easily and the critical departure inclined angle of nanofluid is greater than that of pure water. In addition, the influence of nanofluid on bubble sliding is not significant compared with pure water.

Condensation of refrigerants in horizontal microfin tubes: comparison of prediction methods for heat transfer

Energy Technology Data Exchange (ETDEWEB)

Wang, H S; Honda, H [Kyushu University, Fukuoka (Japan). Institute of Advanced Material Study

2003-06-01

A comparison was made between the predictions of previously proposed empirical correlations and theoretical model and available experimental data for the heat transfer coefficient during condensation of refrigerants in horizontal microfin tubes. The refrigerants tested were R11, R123, R134a, R22 and R410A. Experimental data for six tubes with the tube inside diameter at fin root of 6.49-8.8 8 mm, the fin height of 0.16-0.24 mm, fin pitch of 0.34-0.53 mm and helix angle of groove of 12-20{sup o} were adopted. The r.m.s. error of the predictions for all tubes and all refrigerants decreased in the order of the correlations proposed by Luu and Bergies [ASHRAE Trans. 86 (1980) 293], Cavallini et al. Condensation of new refrigerants inside smooth and enhanced tubes. In: Proc. 19th Int. Cong. Refrigeration, vol. IV, Hague, The Netherlands, 1995. p. 105-114, Shikazono et al. [Trans. Jap. Sco. Mech. Engrs. 64 (1995) 196], Kedzierski and Goncalves [J. Enhanced Heat Transfer 6 (1999) 16], Yu and Koyama [Yu J, Koyama S. Condensation heat transfer of pure refrigerants in microfin tubes. In: Proc. Int. Refrigeration Conference at Purdue Univ., West Lafayette, USA, 1998. p. 325-330], and the theoretical model proposed by Wang et al. [Int. J. Heat Mass Transfer 45 (2002) 1513]. (author)

Author Details

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Solving microwave heating model in a slab using shooting technique. Abstract · Vol 16 (2010) - Articles On the influence of buoyancy and suction/injection In Heat and Mass transfer problems. Abstract · Vol 16 (2010) - Articles Application Of Adomian's Decomposition Method In Solving Nonlinear Partial Differential ...

Fabrication and Characterization of 5 vol.% (Al2O3p + 8 vol.% (Al2O3f/A336 Hybrid Micron and Nano-Composites

Directory of Open Access Journals (Sweden)

Ren Luyang

2017-01-01

Full Text Available Hybrid composites are fabricated by adding two reinforcements into matrix materials so that the expected excellent properties can be achieved through the combined advantages of short fibres, and different size particles (micron or nano, which provide a high degree of design freedom. In this paper, hybrid preforms were produced with the different size reinforcement of the Al2O3 particles and short fibres. The Al-Si alloy-based hybrid composites reinforced by 5 vol. % Al2O3 particles and 8 vol. % Al2O3 fibres were fabricated by preform-squeezing casting route. The structure and performance of composite materials were studied with Transmission Electron Microscopy (TEM and Scanning Electron Microscopy (SEM. The results show that the reinforcements, both particles and fibres, distribute homogeneously in the matrix materials, and the properties of composites are found to improve in comparison with the matrix Al-Si alloy.

Egyptian Journal of Medical Human Genetics - Vol 14, No 3 (2013)

African Journals Online (AJOL)

Egyptian Journal of Medical Human Genetics - Vol 14, No 3 (2013) ... Comparative study: Parameters of gait in Down syndrome versus matched obese and ... episodes in a Japanese child: Clinical, radiological and molecular genetic analysis ...

Arvustuse piirid ja auhinnad : mõtteid kirjanduskriitikast vol 2 / Jan Kaus

Index Scriptorium Estoniae

Kaus, Jan, 1971-

2007-01-01

Tänapäeva eesti kirjanduskriitikast. Vt. ka vol. 1: Kaus, Jan. Eetika, taburetiefekt ja jätkuv objektivisatsioon, Sirp, 15. juuni., lk. 7. Vastukaja: Raudam, Toomas. Arvustuse piiritused //Sirp (2007) 10. aug., lk. 9

South African Journal of Higher Education - Vol 16, No 2 (2002)

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South African Journal of Higher Education - Vol 16, No 2 (2002) ... Rewarding quality teaching in higher education: the evading dream? ... Employers' perceptions of the profile of MBA graduates · EMAIL FULL TEXT EMAIL FULL TEXT

International Journal of Natural and Applied Sciences - Vol 5, No 2 ...

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International Journal of Natural and Applied Sciences - Vol 5, No 2 (2009) ... Illustration of decimation in digital signal processing (DSP) systems using ... of diesel polluted soils on hydrocarbon-utilizing microbial counts and oil degradation ...

Lwati: A Journal of Contemporary Research - Vol 10, No 3 (2013)

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Lwati: A Journal of Contemporary Research - Vol 10, No 3 (2013) ... Evaluation of Social Studies Curriculum on Compassion Dispositions in Students of ... European Trading Companies and Economic Development in the Cross River Basin of ...

Baltische Musik für Streichorchester (Vol. 2) / Hans-Christian Dadelsen

Index Scriptorium Estoniae

Dadelsen, Hans-Christian

1995-01-01

Uuest heliplaadist "Baltische Musik für Streichorchester (Vol. 2). Ostrobothnian Chamber Orchestra, Juha Kangas". Finlandia/East West Records CD 4509-9789-2 (WD: 64'34") Plaadil ka Erkki-Sven Tüüri teos "Insula Deserta"

Journal of Agriculture and Social Research, Vol. 13, No.1, 2013 ...

African Journals Online (AJOL)

Adesope

Journal of Agriculture and Social Research, Vol. 13, No.1, 2013. 56. EFFECT .... respondents who would soon become young entrepreneurs after their training period. The .... world congress on public health, Rio de Janeiro, Brazil. Mohammed ...

Proceedings of the third arab conference on the peaceful uses of atomic energy, vol.a,b

International Nuclear Information System (INIS)

El-Mashri, S.M.

1998-06-01

The publication has been set up as a textbook for peaceful uses of atomic energy vol.A: (1) reactor,materials,energy; (2) nuclear raw materials; (3) radiocesium-waste; (4) nuclear safety; (5) nuclear physics; (6) radiochemistry; (7) radiobiology; vol.B: (1) nuclear medicine; (2) agriculture and soil science; (3) isotope hydrology; (4) food preservation; (5) insect eradication; (6 )industrial application; (7) nuclear activation analysis; (8) health physics and environmental studies

Proceedings of the third arab conference on the peaceful uses of atomic energy, vol.a,b

Energy Technology Data Exchange (ETDEWEB)

El-Mashri, S M [ed.

1998-06-01

The publication has been set up as a textbook for peaceful uses of atomic energy vol.A: (1) reactor,materials,energy; (2) nuclear raw materials; (3) radiocesium-waste; (4) nuclear safety; (5) nuclear physics; (6) radiochemistry; (7) radiobiology; vol.B: (1) nuclear medicine; (2) agriculture and soil science; (3) isotope hydrology; (4) food preservation; (5) insect eradication; (6 )industrial application; (7) nuclear activation analysis; (8) health physics and environmental studies.

Substâncias voláteis em mel floral e mel de melato

Directory of Open Access Journals (Sweden)

CAMPOS Gisélia

2000-01-01

Full Text Available Embora pareça existir um "flavor" característico de mel, a grande variedade de flores disponíveis para a abelha, possibilita uma grande diversidade de flavor e aroma, indicando a presença de vários componentes voláteis. Alguns destes dependem da fisiologia da abelha, dos procedimentos após a colheita e no mel de melato há também a interferência de insetos sugadores e das formigas. Várias substâncias voláteis já foram identificadas, sendo algumas características de determinados méis uniflorais. Com o objetivo de encontrar uma substância volátil característica do mel de melato, seis amostras deste tipo de mel e seis amostras de mel floral foram analisadas usando extração por arraste de gás hidrogênio e cromatografia a gás acoplada a espectrometria de massas. Ácido acético foi encontrado em quatro amostras de mel de melato e em uma amostra de mel floral porém, com menor abundância.

Numerical investigation of the heat transfer of a ferrofluid inside a tube in the presence of a non-uniform magnetic field

Science.gov (United States)

Hariri, Saman; Mokhtari, Mojtaba; Gerdroodbary, M. Barzegar; Fallah, Keivan

2017-02-01

In this article, a three-dimensional numerical investigation is performed to study the effect of a magnetic field on a ferrofluid inside a tube. This study comprehensively analyzes the influence of a non-uniform magnetic field in the heat transfer of a tube while a ferrofluid (water with 0.86 vol% nanoparticles (Fe3O4) is let flow. The SIMPLEC algorithm is used for obtaining the flow and heat transfer inside the tube. The influence of various parameters, such as concentration of nanoparticles, intensity of the magnetic field, wire distance and Reynolds number, on the heat transfer is investigated. According to the obtained results, the presence of a non-uniform magnetic field significantly increases the Nusselt number (more than 300%) inside the tube. Also, the magnetic field induced by the parallel wire affects the average velocity of the ferrofluid and forms two strong eddies in the tube. Our findings show that the diffusion also raises as the concentration of the nanoparticle is increased.

South African Journal of Animal Science - Vol 30, No 2 (2000)

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South African Journal of Animal Science - Vol 30, No 2 (2000) ... Relationship between performance measurements and sale price of Dorper rams in the Northern Cape ... Factors affecting goat production in a communal farming system in the ...

International Journal of Arts and Humanities (IJAH) Ethiopia Vol. 7 (1 ...

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Prof

2018-01-24

Jan 24, 2018 ... International Journal of Arts and Humanities (IJAH). Ethiopia. Vol. 7 (1), S/No ... Department of International and Strategic Studies. Faculty of Arts and ..... American political science review, 98(01), 171-. 189. Stiglitz, J. (2002).

Egyptian Journal of Medical Human Genetics - Vol 13, No 2 (2012)

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Egyptian Journal of Medical Human Genetics - Vol 13, No 2 (2012) ... as independent indicators for B-CLL: Correlation to response to treatment and disease ... Profile of disorders of sexual differentiation in the Northeast region of Cairo, Egypt ...

Sophia: An African Journal of Philosophy - Vol 13, No 1 (2010)

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Sophia: An African Journal of Philosophy - Vol 13, No 1 (2010) ... Letting die: A moral defence · EMAIL FULL TEXT EMAIL FULL TEXT ... Corporate culture: It's impact on corporate life and business practices in ... Current Issue Atom logo

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Items 201 - 226 of 226 ... Vol 9 (1992), The Viability of Solar Energy for Domestic Water Heating in ... Vol 10 (1993), Weight Consideration in the Design of Absorber Plates, Abstract PDF ... Vol 9 (1992), Wind Energy in Ethiopia, Abstract PDF.

Journal of Agricultural Extension Vol. 17 (1) June, 2013 ISSN 1119 ...

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Onyii Ogbonna

Journal of Agricultural Extension. Vol. ... Nigeria one of the largest importers of fish in the developing world, importing ... stratum formed the third stage. ..... Quarterly. 28 (3 & 4): 8-13. Binyotubo, T.E (2011). A guide to fishing gear technology.

Egyptian Journal of Medical Human Genetics - Vol 11, No 1 (2010)

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Egyptian Journal of Medical Human Genetics - Vol 11, No 1 (2010) ... Gene polymorphisms of TNF-α and IL-10 related to rheumatic heart disease · EMAIL ... with familial Mediterranean fever · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

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Analysis of combined heat and mass transfer of water-vapor in a cylinderical zeolite adsorber. Abstract PDF · Vol 16 (1999) - Articles Analysis of combined heat and mass transfer of water- Vapor in a cylinderical zeolite adsorber. Abstract PDF · Vol 17 (2000) - Articles Minimum maintenance solar pump. Abstract PDF.

59 East and Central African Journal of Pharmaceutical Sciences Vol ...

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pharm-chem

East and Central African Journal of Pharmaceutical Sciences. Vol. 16 (2013). There is a misconception that traditional medicine is unique to developing countries of Africa, Asia and. South America. This is certainly not true. Traditional medicine, often referred to as "alternative medicine", is widely used in developed countries ...

Bulletin of the Chemical Society of Ethiopia - Vol 23, No 1 (2009)

African Journals Online (AJOL)

Bulletin of the Chemical Society of Ethiopia - Vol 23, No 1 (2009) ... CHEMICAL REGENERATION OF GRANULAR ACTIVATED CARBON USED IN CITRIC ... FLUORESCENCE PROPERTIES OF 4-ACYL ISOCHROMAN-1,3-DIONES · EMAIL ...

Journal of Agriculture and Social Research (JASR) - Vol 6, No 1 ...

African Journals Online (AJOL)

Journal of Agriculture and Social Research (JASR) - Vol 6, No 1 (2006) ... Econometric analysis of the effect of marketing costs on grain prices in Kaduna State of ... Impact of mass media on adoption of agricultural innovations in Kaduna State, ...

'tomo_display' and 'vol_tools': IDL VM Packages for Tomography Data Reconstruction, Processing, and Visualization

Science.gov (United States)

Rivers, M. L.; Gualda, G. A.

2009-05-01

One of the challenges in tomography is the availability of suitable software for image processing and analysis in 3D. We present here 'tomo_display' and 'vol_tools', two packages created in IDL that enable reconstruction, processing, and visualization of tomographic data. They complement in many ways the capabilities offered by Blob3D (Ketcham 2005 - Geosphere, 1: 32-41, DOI: 10.1130/GES00001.1) and, in combination, allow users without programming knowledge to perform all steps necessary to obtain qualitative and quantitative information using tomographic data. The package 'tomo_display' was created and is maintained by Mark Rivers. It allows the user to: (1) preprocess and reconstruct parallel beam tomographic data, including removal of anomalous pixels, ring artifact reduction, and automated determination of the rotation center, (2) visualization of both raw and reconstructed data, either as individual frames, or as a series of sequential frames. The package 'vol_tools' consists of a series of small programs created and maintained by Guilherme Gualda to perform specific tasks not included in other packages. Existing modules include simple tools for cropping volumes, generating histograms of intensity, sample volume measurement (useful for porous samples like pumice), and computation of volume differences (for differential absorption tomography). The module 'vol_animate' can be used to generate 3D animations using rendered isosurfaces around objects. Both packages use the same NetCDF format '.volume' files created using code written by Mark Rivers. Currently, only 16-bit integer volumes are created and read by the packages, but floating point and 8-bit data can easily be stored in the NetCDF format as well. A simple GUI to convert sequences of tiffs into '.volume' files is available within 'vol_tools'. Both 'tomo_display' and 'vol_tools' include options to (1) generate onscreen output that allows for dynamic visualization in 3D, (2) save sequences of tiffs to disk

Journal of Computer Science and Its Application - Vol 20, No 2 (2013)

African Journals Online (AJOL)

Journal of Computer Science and Its Application - Vol 20, No 2 (2013) ... Fuzzy analysis and adaptive anthropometry model for object identification in surveillance system ... Natural language processing techniques for automatic test questions ...

Heat supply concept for trade. Vol. 3. Environmentally friendly and energy-saving heat supply for public institutions by private operator models (phase 1). Final report. Vol. 2; Waermelieferungskonzept des Handwerks. Bd. 3. Umweltfreundliche und energiesparende Waermeversorgung oeffentlicher Einrichtungen durch private Betreibermodelle (Phase 1). Abschlussbericht. Berichtsband 2

Energy Technology Data Exchange (ETDEWEB)

Hacker, J [ed.; Biermann, J; Locke, R; Meyer, K

1991-01-01

Volume 2 of this report indicates two goals: (3): Development and implementation of concrete heat supply models for public facilities in Berlin; (4): Development of models for cooperation between the heat utility and Berlin trade enterprises. (HW) [Deutsch] Der Berichtsband 2 weist 2 Teilziele auf: Teilziel 3: Erarbeitung und Gestaltung konkreter Waermelieferungsmodelle fuer oeffenliche Einrichtungen in Berlin; Teilziel 4: Gestaltung von Kooperationsmoeglichkeiten zwischen Waermeversorgungsgesellschaft und Handwerksbetrieben in Berlin. (HW)

MANHATTAN DISTRICT HISTORY PROJECT Y THE LOS ALAMOS PROJECT VOL. I INCEPTION UNTIL AUGUST 1945

Energy Technology Data Exchange (ETDEWEB)

Hawkins, D.

1961-12-01

THESE TWO VOLUMES CONSTITUTE A RECORD OF THE TECHNICAL, ADMINISTRATIVE , AND POLICY-MAKING ACTIVITIES OF THE LOS ALAMOS PROJECT (PROJECT Y) FROM ITS INCEPTION UNDER THE MANHATTAN DISTRICT THROUGH THE DEVELOPMENT OF THE ATOMIC BOMB (VOL. I), AND DURING THE PERIOD FOLLOWING THE END OF WORLD WAR II UNTIL THE MANHATTAN DISTRICT RELINQUISHED CONTROL TO THE ATOMIC ENERGY COMMISSION AS OF JANUARY 1947 (VOL. II). ALTHOUGH SECURITY REGULATIONS HAVE REQUIRED SOME DELETIONS IN THE ORIGINAL TEXT OF THE TWO VOLUMES, EVERY EFFORT HAS BEEN MADE TO RETAIN THE ORIGINAL LANGUAGE AND EXPRESSIONS OF THE AUTHORS.

Siim Nestor soovitab : Tallinn Doom Night vol.1. Odessa Pop / Siim Nestor

Index Scriptorium Estoniae

Nestor, Siim, 1974-

2006-01-01

Soome doom-metal ansambel Reverend Bizarre üritusel "Tallinn Doom Night vol.1" 8. dets. klubis Rockstar's. Indipoppi viljelev Rootsi duo My Darling Yoy! üritusel "Odessa Pop" 9. dets. Tallinnas klubis KuKu

ASJP_vol11_Special_Issue_2013 ODD SIZE NEW.indd

African Journals Online (AJOL)

opperwjj

African Safety Promotion Journal, Vol. 11, No. ... ABSTRACT. This article takes as its starting point that crime fiction is a public and political response to ... Finally, Hart, Orford's hard-boiled female detective figure, is assessed to ..... Four of Orford's Clare Hart novels are situated in the Cape where Anene Booysen died. In.

Modern technical solutions of gas-fired heating devices of household and communal use and analysis of their testing

Energy Technology Data Exchange (ETDEWEB)

Bodzon, L.; Radwan, W. [Oil Mining and Gas Engineering Institute, Cracow (Poland)

1995-12-31

A review of technical solutions for gas-fired heating devices for household and communal use in Poland is presented. Based upon the analysis it is stated that the power output of Polish and foreign boilers ranges between 9 and 35 kW. The carbon monoxide content in flue gases reaches (on average) 0.005 vol.%, i.e., it is much lower than the maximum permissible level. Temperature of flue gases (excluding condensation boilers and those with air-tight combustion chamber) ranges between 150 and 200{degrees}C and their heating efficiency reaches 87-93%. The best parameters are given for condensation boilers, however they are still not widespread in Poland for the high cost of the equipment and assembling works. Among the heaters, the most safe are convection devices with closed combustion chamber; their efficiency is also the highest. Thus, it is concluded that a wide spectrum of high efficiency heating devices with good combustion parameters are available. The range of output is sufficient to meet household and communal requirement. They are however - predominantly - units manufactured abroad. It is difficult to formulate the program aimed at the improvement of the technique of heating devices made in Poland, and its implementation is uncertain because the production process is broken up into small handicraft workshops.

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African Journals Online (AJOL)

Items 301 - 350 of 823 ... Vol 8, No 2 (2015), Effects of different heat processing methods on the ... Vol 10, No 1 (2017), Effects on the electro-mechanical properties of ... Vol 2, No 2 (2009), Ethanol oxidation over Au/TiO2 catalysis, Abstract PDF.

Soil-structure interaction Vol.3. Influence of ground water

Energy Technology Data Exchange (ETDEWEB)

Costantino, C J

1986-04-01

This study has been performed for the Nuclear Regulatory Commission (NRC) by the Structural Analysis Division of Brookhaven National Laboratory (BNL). The study was conducted during the fiscal year 1965 on the program entitled 'Benchmarking of Structural Engineering Problems' sponsored by NRC. The program considered three separate but complementary problems, each associated with the soil-structure interaction (551) phase of the seismic response analysis of nuclear plant facilities. The reports, all entitled Soil-Structure Interaction, are presented in three separate volumes, namely: Vol. 1 Influence of Layering by AJ Philippacopoulos, Vol. 2 Influence of Lift-Off by C.A. Miller, Vol. 3 Influence of Ground Water by C.J. Costantino. The two problems presented in Volumes 2 and 3 were conducted at the City University of New York (CUNY) under subcontract to BNL. This report, Volume 3 of the report, presents a summary of the first year's effort on the subject of the influence of foundation ground water on the SSI phenomenon. A finite element computer program was developed for the two-phased formulation of the combined soil-water problem. This formulation is based on the Biot dynamic equations of motion for both the solid and fluid phases of a typical soil. Frequency dependent interaction coefficients were generated for the two-dimensional plane problem of a rigid surface footing moving against a saturated linear soil. The results indicate that interaction coefficients are significantly modified as compared to the comparable values for a dry soil, particularly for the rocking mode of response. Calculations were made to study the impact of the modified interaction coefficients on the response of a typical nuclear reactor building. The amplification factors for a stick model placed atop a dry and saturated soil were computed. It was found that pore water caused the rocking response to decrease and translational response to increase over the frequency range of interest, as

Heat pipe heat exchangers in heat recovery systems

Energy Technology Data Exchange (ETDEWEB)

Stulc, P; Vasiliev, L L; Kiseljev, V G; Matvejev, Ju N

1985-01-01

The results of combined research and development activities of the National Research Institute for Machine Design, Prague, C.S.S.R. and the Institute for Heat and Mass Transfer, Minsk, U.S.S.R. concerning intensification heat pipes used in heat pipe heat exchangers are presented. This sort of research has been occasioned by increased interest in heat power economy trying to utilise waste heat produced by various technological processes. The developed heat pipes are deployed in construction of air-air, gas-air or gas-gas heat recovery exchangers in the field of air-engineering and air-conditioning. (author).

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African Journals Online (AJOL)

Items 1 - 50 of 103 ... Vol 6, No 1 (2016), Building Resilience in Nigeria's Energy Sector for Sustainable Development, Abstract. S K Fasogbon, A A Dare. Vol 6, No 2 (2016) ... Vol 5, No 1 (2015), Design of a Solar Water Heating System for Kuti Hall, University of Ibadan, Ibadan, Abstract. IF Odesola, TG Omolaja. Vol 2, No 1 ...

Análisis de los compuestos volátiles de la ciruela amarilla (Prunus domestica L. ssp. domestica

Directory of Open Access Journals (Sweden)

Yineth Ruiz

2011-01-01

Full Text Available El aroma de las frutas se debe a los constituyentes volátiles presentes que, aunque se encuentran en muy bajas concentraciones, contribuyen al aroma global en grados muy diversos. Se hace necesario usar técnicas de aislamiento y concentración que garanticen el análisis de una composición química semejante a la de la fruta. Este trabajo tuvo como objetivo el análisis de los compuestos volátiles de la ciruela amarilla (Prunus domestica L. ssp. domestica por el método de evaporación del aroma asistida por solvente (SAFE. Este método utiliza un equipo de destilación conectado a una bomba de alto vacío que ofrece la posibilidad de aislar rápidamente compuestos volátiles sin daño térmico en diferentes matrices alimentarias. La separación e identificación de los compuestos volátiles se realizó por cromatografía de gases-espectrometría de masas (GC-MS. Se identificaron 47 compuestos (6,55 mg/kg de pulpa de fruta, entre ellos 14 alcoholes, 8 aldehídos, 7 ésteres, 5 cetonas, 4 ácidos carboxílicos, 4 hidrocarburos aromáticos, 3 lactonas, un compuesto azufrado y una hidroxicetona; 16 de ellos se informan por primera vez. El acetato de etilo (2,88 mg/kg, etanol (1 mg/kg y ácido octanoico (0,78 mg/kg fueron los constituyentes volátiles mayoritarios de esta variedad de ciruela.

Análisis de los compuestos volátiles de la ciruela amarilla (Prunus domestica L. ssp. domestica

Directory of Open Access Journals (Sweden)

Yineth Ruiz

2011-06-01

Full Text Available El aroma de las frutas se debe a los constituyentes volátiles presentes que, aunque se encuentran en muy bajas concentraciones, contribuyen al aroma global en grados muy diversos. Se hace necesario usar técnicas de aislamiento y concentración que garanticen el análisis de una composición química semejante a la de la fruta. Este trabajo tuvo como objetivo el análisis de los compuestos volátiles de la ciruela amarilla (Prunus domestica L. ssp.domestica por el método de evaporación del aroma asistida por solvente (SAFE. Este método utiliza un equipo de destilación conectado a una bomba de alto vacío que ofrece la posibilidad de aislar rápidamente compuestos volátiles sin daño térmico en diferentes matrices alimentarias. La separación e identificación de los compuestos volátiles se realizó por cromatografía de gases-espectrometría de masas (GC-MS. Se identificaron 47 compuestos (6,55 mg/kg de pulpa de fruta, entre ellos 14 alcoholes, 8 aldehídos, 7 ésteres, 5 cetonas, 4 ácidos carboxílicos, 4 hidrocarburos aromáticos, 3 lactonas, un compuesto azufrado y una hidroxicetona; 16 de ellos se informan por primera vez. El acetato de etilo (2,88 mg/kg, etanol (1 mg/kg y ácido octanoico (0,78 mg/kg fueron los constituyentes volátiles mayoritarios de esta variedad de ciruela.

Journal of Agriculture, Forestry and the Social Sciences - Vol 5, No 2 ...

African Journals Online (AJOL)

Journal of Agriculture, Forestry and the Social Sciences - Vol 5, No 2 (2007) ... Marketing Of Bushmeat In Peri-Urban Areas Of Ibadan Metropolis Of Oyo State, ... Sport Fisheries Potentials Of Agbokim Waterfalls, Cross River State, Nigeria ...

Bulletin of the Chemical Society of Ethiopia - Vol 3, No 2 (1989)

African Journals Online (AJOL)

Bulletin of the Chemical Society of Ethiopia - Vol 3, No 2 (1989) ... Synthesis and characterization of gold (III) halide complexes of some pyridine ... Molluscicidal activities of some alkaloids · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

Bulletin of the Chemical Society of Ethiopia - Vol 27, No 3 (2013)

African Journals Online (AJOL)

Bulletin of the Chemical Society of Ethiopia - Vol 27, No 3 (2013) ... of the psychoactive phenylpropylamino alkaloids of khat (Catha edulis Forsk) chewing ... Synthesis and characterization of CdTe quantum dots by one-step method · EMAIL ...

Tanzania Dental Journal Vol. 14 No. 1, May 2007 In vitro efficacy of ...

African Journals Online (AJOL)

user

2007-05-30

May 30, 2007 ... Tanzania Dental Journal Vol. 14 No. ... 2 Centre for Stomatological Research, School of Dentistry, University of Pretoria, Pretoria, South Africa. ..... Interestingly, clinical trials .... International Organization for Standardization,.

Estudo comparativo dos óleos voláteis de algumas espécies de Piperaceae

Directory of Open Access Journals (Sweden)

J.M.O. Mesquita

Full Text Available O presente trabalho teve por objetivo a análise comparativa dos óleos voláteis de espécies da família Piperaceae. As espécies estudadas foram as seguintes: Piper aduncum, P. amalago, P. arboreum, P. cernuum, P. hispidum, P. regnelii, P. submarginalum, P. vicosanum e Pothomorphe umbellata. A análise dos óleos voláteis foi efetuada pela combinação de técnicas de Cromatografia de Fase Gasosa (CG e de Cromatografia de Fase Gasosa acoplada a Espectrometria de Massa (CG/EM. A porcentagem de identificação dos constituintes nas análises dos óleos voláteis de Piper aduncum, P. amalago, P. vicosanum, P. submarginalum e Pothomorphe umbellata, atingiu valores superiores a 80%. Houve predominância de compostos de natureza sesquiterpênica nas composições químicas das espécies analisadas, com exceção de P. hispidum, P. submarginalum e P. vicosanum onde a predominância na composição foi de monoterpenos. Pelos dados apresentados observou-se que, dentre os compostos majoritários, os mais freqüentes, nas 9 espécies estudadas, foram beta-pineno (9/9 e espatulenol (9/9, seguidos por E-cariofileno (8/9, óxido de cariofileno (8/9, germacreno D (7/9, alfa-pineno (7/9 e limoneno (6/9. Pela primeira vez se relata a composição dos óleos voláteis de P. submarginalum e P vicosanum.

Experimental investigation on the effect of nanofluid on the thermal performance of symmetric sintered U shaped heat pipe

Science.gov (United States)

Nazarimanesh, Meysam; Yousefi, Tooraj; Ashjaee, Mehdi

2016-07-01

In this study, the impact of Entrance Power and Silver nanofluid concentration (with base fluid ethanol and DI-water) on heat pipe thermal performance are considered. In order to reach the aim a U-shaped sintered heat pipe is utilized which causes occupied space to decline. The length of the heat pipe is 135 mm in each branch. On account of recognition the effect of working fluid on heat pipe thermal performance, thermal resistance and overall heat transfer coefficient in base working fluid and nano-colloidal silver are measured in the shape of thermosyphon. The working fluid is with volume percentages of 70 ethanol and 30 distilled water. The average size pertaining to the nanoparticle applied is 40 nm. In addition, the influences of nanofluid concentrations are measured by comparing three concentrations 0.001, 0.005, 0.1 vol%. The range of entrance power is from 10 to 40 W and the temperature of coolant has been changed from 20 to 40 °C. The results of the experiment indicate that by increasing entrance power, the temperatures of the condenser, evaporator and working temperature experience a rise. Furthermore, this causes a decrease of thermal resistance and an increase of overall heat transfer coefficient. A comparison of three concentrations reveals that in concentration of 50 ppm, thermal resistance compared to the base fluid has decreased to 42.26 % and overall heat transfer coefficient has gone up to 1883 (W/m2·°K) . Also, due to unexpected changes in concentration of 1000 ppm, the existence of an optimized concentration for the silver nanofluid in this heat pipe with this geometry has been clear.

Journal of Medicine and Biomedical Research - Vol 14, No 1 (2015)

African Journals Online (AJOL)

Journal of Medicine and Biomedical Research - Vol 14, No 1 (2015) ... Histopathological effects of oral and subcutaneous administration of Roselle Calyx ... Ameliorative effect of Vitamin C on lead induced hepatotoxicty in rats · EMAIL ... Effect of Hibiscus sabdariffa calyx extract on stressed rabbit plasma cholesterol status ...

Supersymmetric mechanics. Vol. 2. The attractor mechanism and space time singularities

International Nuclear Information System (INIS)

Bellucci, S.; Marrani, A.; Ferrara, S.

2006-01-01

This is the second volume in a series of books on the general theme of Supersymmetric Mechanics; the series is based on lectures and discussions held in 2005 and 2006 at the INFN-Laboratori Nazionali di Frascati. The first volume appears as Lect. Notes Physics, Vol. 698 ''Supersymmetric Mechanics, Vol.1: Supersymmetry, Noncommutativity and Matrix Models'' (2006) ISBN: 3-540-33313-4. The present extensive lecture supplies a pedagogical introduction, at the non-expert level, to the attractor mechanism in space-time singularities. In such a framework, supersymmetry seems to be related to dynamical systems with fixed points, describing the equilibrium state and the stability features of the thermodynamics of black holes. After a qualitative overview, explicit examples realizing the attractor mechanism are treated at some length; they include relevant cases of asymptotically flat, maximal and non-maximal, extended supergravities in 4 and 5 dimensions. A number of recent advances along various directions of research on the attractor mechanism are also given. (orig.)

EJOTMAS: Ekpoma Journal of Theatre and Media Arts - Vol 4, No 1 ...

African Journals Online (AJOL)

EJOTMAS: Ekpoma Journal of Theatre and Media Arts - Vol 4, No 1-2 (2013) ... Dance for children: a functional education for national growth · EMAIL FREE FULL ... From 'folkism' to performance: a new scenic strategy for audience integration ...

EJOTMAS: Ekpoma Journal of Theatre and Media Arts - Vol 3, No 1 ...

African Journals Online (AJOL)

EJOTMAS: Ekpoma Journal of Theatre and Media Arts - Vol 3, No 1-2 (2010) ... The African composer as a social critic · EMAIL FREE FULL TEXT EMAIL FREE ... Potentials of the television in reinventing the Nigerian tourism industry · EMAIL ...

Vím, proč volím: Analýza mediální kampaně

OpenAIRE

Skřebská, Aneta

2013-01-01

This thesis contains analysis of a media campaign I know why I vote (Vím, proč volím) which took place in 2013 and 2014. Aim of this thesis is to define tools that were used when running a media campaign, evaluate its effectiveness, and provide suggestions for further improvements. The theoretical part defines environment of a non-profit organization and specifics of its marketing and public relations strategies. The practical part analyses the campaign I know why I vote (Vím, proč volím) in ...

Egyptian Journal of Medical Human Genetics - Vol 12, No 2 (2011)

African Journals Online (AJOL)

Egyptian Journal of Medical Human Genetics - Vol 12, No 2 (2011) ... Serum interferon-alpha level in first degree relatives of systemic lupus erythematosus patients: Correlation with autoantibodies titers · EMAIL FREE FULL TEXT EMAIL FREE FULL ... LB Salah, CB Salem, F B'Chir, K Bouraoui, F Broly, S Saguem, 183-186.

Automatic individualized contrast medium dosage during hepatic computed tomography by using computed tomography dose index volume (CTDI{sub vol})

Energy Technology Data Exchange (ETDEWEB)

Svensson, Anders; Cederlund, Kerstin; Aspelin, Peter; Brismar, Torkel B. [Intervention and Technology at Karolinska Institutet, Department of Clinical Science, Division of Medical Imaging and Technology, Stockholm (Sweden); Karolinska University Hospital in Huddinge, Department of Radiology, Stockholm (Sweden); Bjoerk, Jonas [FoU-centrum Skaane Skaanes Universitetssjukhus i Lund, Lund (Sweden); Nyman, Ulf [University of Lund, Department of Diagnostic Radiology, Lasarettet Trelleborg, Trelleborg (Sweden)

2014-08-15

To compare hepatic parenchymal contrast media (CM) enhancement during multi-detector row computed tomography (MDCT) and its correlation with volume pitch-corrected computed tomography dose index (CTDI{sub vol}) and body weight (BW). One hundred patients referred for standard three-phase thoraco-abdominal MDCT examination were enrolled. BW was measured in the CT suite. Forty grams of iodine was administered intravenously (iodixanol 320 mg I/ml at 5 ml/s or iomeprol 400 mg I/ml at 4 ml/s) followed by a 50-ml saline flush. CTDI{sub vol} presented by the CT equipment during the parenchymal examination was recorded. The CM enhancement of the liver was defined as the attenuation HU of the liver parenchyma during the hepatic parenchymal phase minus the attenuation in the native phase. Liver parenchymal enhancement was negatively correlated to both CTDI{sub vol} (r = -0.60) and BW (r = -0.64), but the difference in correlation between those two was not significant. CTDI{sub vol} may replace BW when adjusting CM doses to body size. This makes it potentially feasible to automatically individualize CM dosage by CT. (orig.)

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African Journals Online (AJOL)

Items 51 - 100 of 204 ... Vol 4, No 1 (2001), Effect of harvest methods on yield and quality of Marketable flowers of greenhouse rose cultivars of different growth habits, Abstract PDF. TJ Msogoya, A ... Vol 3, No 2 (2000), Effects of moist heat and dry heat on the nutritional value of velvet beans (Mucuna pruriens Var. Utilis) for the ...

Heat pipe heat storage performance

Energy Technology Data Exchange (ETDEWEB)

Caruso, A; Pasquetti, R [Univ. de Provence, Marseille (FR). Inst. Universitaire des Systemes; Grakovich, L P; Vasiliev, L L [A.V. Luikov Heat and Mass Transfer Inst. of the BSSR, Academy of Sciences, Minsk (BY)

1989-01-01

Heat storage offers essential thermal energy saving for heating. A ground heat store equipped with heat pipes connecting it with a heat source and to the user is considered in this paper. It has been shown that such a heat exchanging system along with a batch energy source meets, to a considerable extent, house heating requirements. (author).

Análisis de compuestos volátiles en cilantro ( L. Análisis de compuestos volátiles en cilantro (Coriandrum sativum L.

Directory of Open Access Journals (Sweden)

Tábata Rosales-Reyes

2012-02-01

Full Text Available In the present study, volatile compounds were recovered from the fresh leaves and stems ofcilantro (Coriandrum sativum L. by two methods: Liquid-Solid Extraction (LSE and SimultaneousDistillation-Extraction (SDE. The identification and quantification was done byGas Chromatography-Mass Spectrometry (GC-MS. Fourteen compounds were characterizedby LSE and GC-MS; whereas by SDE and GC-MS, they were twenty three compounds.The statistical analysis revealed significant quantitative differences (p ≤ 0,05 between theanalyzed techniques (LSE and SDE. In this work, the Simultaneous Distillation-Extractionshowed the greater identification and total concentration of volatile compounds. Aldehydes,monoterpenes, and alcohols comprised 78% of the volatile found for two methods, the restwere hydrocarbons. (E-2-decenal was the most abundant compound in cilantro in bothextraction techniques. En el presente estudio se recuperaron los compuestos volátiles de las hojas y los tallos frescos de cilantro (Coriandrum sativum L. mediante dos métodos: Extracción Sólido Líquido (LSE y Extracción-Destilación Simultánea (SDE. La identificación y cuantificación fue por Cromatografía de Gases-Espectrometría de Masas (GC-MS. Se caracterizaron catorce compuestos por LSE y GC-MS; mientras que por SDE y GC-MS, fueron veintitrés compuestos. El análisis estadístico reveló significativas diferencias cuantitativas (p ≤ 0,05 entre las técnicas analizadas (LSE y SDE. En este trabajo, la Extracción-Destilación Simultánea arrojó la mayor identificación y concentración total de compuestos volátiles. Los aldehídos, monoterpenos y alcoholes comprendieron el 78% de los volátiles encontrados por los dos métodos, el resto fueron hidrocarburos. En ambas técnicas de extracción el (E-2-decenal fue el compuesto más abundante en el cilantro.

Hybrid finite volume/ finite element method for radiative heat transfer in graded index media

Science.gov (United States)

Zhang, L.; Zhao, J. M.; Liu, L. H.; Wang, S. Y.

2012-09-01

The rays propagate along curved path determined by the Fermat principle in the graded index medium. The radiative transfer equation in graded index medium (GRTE) contains two specific redistribution terms (with partial derivatives to the angular coordinates) accounting for the effect of the curved ray path. In this paper, the hybrid finite volume with finite element method (hybrid FVM/FEM) (P.J. Coelho, J. Quant. Spectrosc. Radiat. Transf., vol. 93, pp. 89-101, 2005) is extended to solve the radiative heat transfer in two-dimensional absorbing-emitting-scattering graded index media, in which the spatial discretization is carried out using a FVM, while the angular discretization is by a FEM. The FEM angular discretization is demonstrated to be preferable in dealing with the redistribution terms in the GRTE. Two stiff matrix assembly schemes of the angular FEM discretization, namely, the traditional assembly approach and a new spherical assembly approach (assembly on the unit sphere of the solid angular space), are discussed. The spherical assembly scheme is demonstrated to give better results than the traditional assembly approach. The predicted heat flux distributions and temperature distributions in radiative equilibrium are determined by the proposed method and compared with the results available in other references. The proposed hybrid FVM/FEM method can predict the radiative heat transfer in absorbing-emitting-scattering graded index medium with good accuracy.

Hybrid finite volume/ finite element method for radiative heat transfer in graded index media

International Nuclear Information System (INIS)

Zhang, L.; Zhao, J.M.; Liu, L.H.; Wang, S.Y.

2012-01-01

The rays propagate along curved path determined by the Fermat principle in the graded index medium. The radiative transfer equation in graded index medium (GRTE) contains two specific redistribution terms (with partial derivatives to the angular coordinates) accounting for the effect of the curved ray path. In this paper, the hybrid finite volume with finite element method (hybrid FVM/FEM) (P.J. Coelho, J. Quant. Spectrosc. Radiat. Transf., vol. 93, pp. 89-101, 2005) is extended to solve the radiative heat transfer in two-dimensional absorbing-emitting-scattering graded index media, in which the spatial discretization is carried out using a FVM, while the angular discretization is by a FEM. The FEM angular discretization is demonstrated to be preferable in dealing with the redistribution terms in the GRTE. Two stiff matrix assembly schemes of the angular FEM discretization, namely, the traditional assembly approach and a new spherical assembly approach (assembly on the unit sphere of the solid angular space), are discussed. The spherical assembly scheme is demonstrated to give better results than the traditional assembly approach. The predicted heat flux distributions and temperature distributions in radiative equilibrium are determined by the proposed method and compared with the results available in other references. The proposed hybrid FVM/FEM method can predict the radiative heat transfer in absorbing-emitting-scattering graded index medium with good accuracy.

African Review of Economics and Finance - Vol 6, No 1 (2014)

African Journals Online (AJOL)

Journal Home > Archives > Vol 6, No 1 (2014) ... 7Implication of mergers and acquisitions on stock returns before and during the 2007–2009 credit crunch: An event study ... 9Socio-economic adaptation strategies of the urban poor in the Lagos ... and on-the-ground developing countries' realities for improved management ...

South African Journal of Clinical Nutrition - Vol 29, No 3 (2016)

African Journals Online (AJOL)

South African Journal of Clinical Nutrition - Vol 29, No 3 (2016) ... C Marais, L van Wyk, M Conradie, D Hall, 118-121. Arm-associated measurements as estimates of true height in black and white young adults of both genders: an exploratory study, Pietermaritzburg, KwaZulu-Natal, South Africa · EMAIL FREE FULL TEXT ...

MANHATTAN DISTRICT HISTORY PROJECT Y THE LOS ALAMOS PROJECT VOL. II AUGUST 1945 THROUGH DECEMBER 1946

Energy Technology Data Exchange (ETDEWEB)

Truslow, E. C.; Smith, R. C.

1961-12-01

THESE TWO VOLUMES CONSTITUTE A RECORD OF THE TECHNICAL, ADMINISTRATIVE , AND POLICY-MAKING ACTIVITIES OF THE LOS ALAMOS PROJECT (PROJECT Y) FROM ITS INCEPTION UNDER THE MANHATTAN DISTRICT THROUGH THE DEVELOPMENT OF THE ATOMIC BOMB (VOL. I), AND DURING THE PERIOD FOLLOWING THE END OF WORLD WAR II UNTIL THE MANHATTAN DISTRICT RELINQUISHED CONTROL TO THE ATOMIC ENERGY COMMISSION AS OF JANUARY 1947 (VOL. II). ALTHOUGH SEC URITY REGULATIONS HAVE REQUIRED SOME DELETIONS IN THE ORIGINAL TEXT OF THE TWO VOLUMES, EVERY EFFORT HAS BEEN MADE TO RETAIN THE ORIGINAL LANGUGAGE AND EXPERSSIONS OF THE AUTHORS.

International congress on forest decline research: State of knowledge and perspectives. Vol. 1. Proceedings

International Nuclear Information System (INIS)

Ulrich, B.

1989-01-01

In the two lecture volumes of the Proceedings of the International Congress on Forest Decline Research the papers are presented according to the topics of the plenary and poster sessions. The sessions had been devoted to the damage symptoms in forest decline, to the main stressors (atmosphere, climate, soil, biota), to the effects of the stressors (on rhizosphere, on decomposers, and on plants) (see vol. 1), to case studies (in Germany and abroad), to regional comparisons, to critical loads, and to silvicultural measures (see vol. 2). Additionally personal impressions about the forest decline phenomen in Germany and its causes and opinions about the perspective in regard to research needs, to silvicultural practices and to emission control are given. (orig./vhe)

International congress on forest decline research: State of knowledge and perspectives. Vol. 2. Proceedings

International Nuclear Information System (INIS)

Ulrich, B.

1989-01-01

In the two lecture volumes of the Proceedings of the International Congress on Forest Decline Research the papers are presented according to the topics of the plenary and poster sessions. The sessions had been devoted to the damage symptoms in forest decline, to the main stressors (atmosphere, climate, soil, biota), to the effects of the stressors (on rhizosphere, on decomposers, and on plants) (see vol. 1), to case studies (in Germany and abroad), to regional comparisons, to critical loads, and to silvicultural measures (see vol. 2). Additionally personal impressions about the forest decline phenomen in Germany and its causes and opinions about the perspective in regard to research needs, to silvicultural practices and to emission control are given. (orig./vhe)

Development of CuO–ethylene glycol nanofluids for efficient energy management: Assessment of potential for energy recovery

International Nuclear Information System (INIS)

Allen Zennifer, M.; Manikandan, S.; Suganthi, K.S.; Leela Vinodhan, V.; Rajan, K.S.

2015-01-01

Highlights: • CuO–ethylene glycol nanofluids prepared and characterized. • Maximum thermal conductivity enhancement of 14.1% at 50 °C for 1 vol% nanofluid. • Heat transfer performance in correspondence with improved transport properties. • 11.8% enhancement in heat transfer rate for 1 vol% nanofluid. - Abstract: Ethylene glycol (EG) plays an important role as coolant in sub-artic and artic regions owing to its low freezing point. However one of the limitations of ethylene glycol for energy management is its low thermal conductivity, which can be improved by addition of nanoparticles. In the present work, cupric oxide nanoparticles have been synthesized followed by dispersion in ethylene glycol through extended probe ultrasonication without addition of chemical dispersing agent. Temperature dependency of thermal conductivity of 1 vol% CuO–ethylene glycol nanofluid exhibited a minimum at a critical temperature corresponding to lower thickness of interfacial layers and negligible Brownian motion. The influence of liquid layering on thermal conductivity was predominant at temperatures below critical temperature leading to higher thermal conductivity at lower temperature. Brownian motion-induced microconvection resulted in thermal conductivity increase with temperature above the critical temperature. About 14.1% enhancement in thermal conductivity was obtained at 50 °C for 1 vol% CuO–ethylene glycol nanofluid. The viscosity of CuO–ethylene glycol nanofluid was lower than the viscosity of ethylene glycol at temperatures below 50 °C and 120 °C for 1 vol% and 0.5 vol% CuO–ethylene glycol nanofluids. Our data reveal that the CuO–ethylene glycol nanofluids are better coolants than ethylene glycol for transient cooling under constant heat flux conditions with 11.8% enhancement in heat transfer rate for 1 vol% CuO–ethylene glycol nanofluid. Hence the use of ethylene glycol-based nanofluids is a promising approach for energy management.

Effect of heat treatment on friction and wear behavior of al-6061 composite reinforced with 10% submicron Al2O3 particles

International Nuclear Information System (INIS)

AlQutub, Amro M

2009-01-01

The present research aims at investigating experimentally the effect of heat treatment on the hardness, wear behavior, and friction properties of 6061 Al composite reinforced with sub-micron Al2O3 (10% vol.) produced by powder metallurgy. Heat treatment of the as-received composite starts by the solution treatment at a temperature of 550 degree C for a period of two hours followed by quenching in chilled water and then age hardening at 175 degree C for different periods. It is illustrated that heat treatment has relatively small effect on the hardness of the composite. This can be attributed to the large interface areas between the matrix and the sub-micron alumina in the composite, which reduces the whole concentration of vacancies in the matrix. The result is reduced efficiency of age hardening. For this reason, wear and friction tests were limited to the heat treated composite with four hours aging only. A pin-on-disc tribometer was used to conduct wear and friction tests against AISI 4140 at room temperature for both as-received composite and heat treated composite (with four hours of aging) for comparison. Wear tests indicate that heat treatment has the advantage of increasing transition load to severe wear by 30% compared to as-received composite. On the other hand, at high loads heat treatment results in larger delaminated flakes on the worn surface, indicating reduced fracture toughness. This, in turn, resulted in higher wear rates compared to the as-received composite. Dry friction coefficient is practically unaffected by the heat treatment. (author)

Heat pipes and heat pipe exchangers for heat recovery systems

Energy Technology Data Exchange (ETDEWEB)

Vasiliev, L L; Grakovich, L P; Kiselev, V G; Kurustalev, D K; Matveev, Yu

1984-01-01

Heat pipes and heat pipe exchangers are of great importance in power engineering as a means of recovering waste heat of industrial enterprises, solar energy, geothermal waters and deep soil. Heat pipes are highly effective heat transfer units for transferring thermal energy over large distance (tens of meters) with low temperature drops. Their heat transfer characteristics and reliable working for more than 10-15 yr permit the design of new systems with higher heat engineering parameters.

Creative Artist: A Journal of Theatre and Media Studies - Vol 8, No 2 ...

African Journals Online (AJOL)

Creative Artist: A Journal of Theatre and Media Studies - Vol 8, No 2 (2014) ... Social Media Use And Real-life Social Relationships: (A Study of Nnamdi ... The Impacts of Slavery and Colonialism on African Traditional Music and Dance ...

49. Meeting of the Chemical Societies: Proceedings of the contributions. Vol. 2

International Nuclear Information System (INIS)

Uher, M.; Benes, P.; Carsky, J.; Chodak, I.; Kuruc, J.; Romancik, V.; Stasko, A. Slovak Technical Univ., Bratislava

1995-09-01

The publication has been set up as a abstracts of the meeting dealing with chemical problems. The book (Vol. 2) consists of the sections: (C) Physical chemistry; (D) History of the chemistry; (E) Food chemistry and technology; (D) Environmental chemistry; (E) Nuclear chemistry and radioecology; (H) Synthetic polymers

Journal of Child and Adolescent Mental Health - Vol 25, No 1 (2013)

African Journals Online (AJOL)

Journal of Child and Adolescent Mental Health - Vol 25, No 1 (2013) ... Autism spectrum disorders—Global challenges and local opportunities · EMAIL ... Peer education training for sexual health and well-being in public high schools in ... Evaluation of a school-based intervention programme for South African children of ...

Heat pipes in modern heat exchangers

International Nuclear Information System (INIS)

Vasiliev, Leonard L.

2005-01-01

Heat pipes are very flexible systems with regard to effective thermal control. They can easily be implemented as heat exchangers inside sorption and vapour-compression heat pumps, refrigerators and other types of heat transfer devices. Their heat transfer coefficient in the evaporator and condenser zones is 10 3 -10 5 W/m 2 K, heat pipe thermal resistance is 0.01-0.03 K/W, therefore leading to smaller area and mass of heat exchangers. Miniature and micro heat pipes are welcomed for electronic components cooling and space two-phase thermal control systems. Loop heat pipes, pulsating heat pipes and sorption heat pipes are the novelty for modern heat exchangers. Heat pipe air preheaters are used in thermal power plants to preheat the secondary-primary air required for combustion of fuel in the boiler using the energy available in exhaust gases. Heat pipe solar collectors are promising for domestic use. This paper reviews mainly heat pipe developments in the Former Soviet Union Countries. Some new results obtained in USA and Europe are also included

AJESMS_ Vol 8 2010 August 15 2011

African Journals Online (AJOL)

Prof. Mereku

2010-08-15

Aug 15, 2010 ... further reduction in plasma volume during exercise. Recall that body water content regulates sweating, and sweating provides our best method of heat loss during exercise. So, adequate body water is essential to avoid heat injury; e.g., heat exhaustion or heat stroke (Convertino, 1991). Body water retention ...

Browse Title Index

African Journals Online (AJOL)

Items 1 - 34 of 34 ... Vol 3, No 1 (2005), Analysis of the heat exchanger network of the topping unit of the Tema Oil Refinery, Abstract. G Afrane. Vol 2, No 2 (2004), Clam shells aggregates for housing construction, Abstract. E Atiemo. Vol 2, No 1 (2004), Commercial appraisal of Pozzolana plant in Ghana, Abstract. E Atiemo.

Synthèse: Revue des Sciences et de la Technologie - Vol 24 (2015)

African Journals Online (AJOL)

Synthèse: Revue des Sciences et de la Technologie - Vol 24 (2015) ... hygrothermique en eau douce sur un composite unidirectionnel verre-époxy · EMAIL ... Problèmes de type obstacle : algorithmes de résolution · EMAIL FREE FULL TEXT ...

Proceedings of the 3rd international conference on heat exchangers, boilers and pressure vessels (HEB-97). Vol.1 (Research Papers)

International Nuclear Information System (INIS)

1997-04-01

This conference was held on 5-6 Apr 1997 in Alexandria. the specialists discussed heat exchangers, boilers and pressure vessels. more than 200 papers were presented in the meetings. it contains of data, figures and tables

Proceedings of the 3rd international conference on heat exchangers, boilers and pressure vessels (HEB-97). Vol.1 (Research Papers)

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-04-01

This conference was held on 5-6 Apr 1997 in Alexandria. the specialists discussed heat exchangers, boilers and pressure vessels. more than 200 papers were presented in the meetings. it contains of data, figures and tables.

Influence of temperature on the inhibitory potency of Eucalyptus honey against Candida albicans

Directory of Open Access Journals (Sweden)

Ahmed Moussa

2012-12-01

Full Text Available Objective: To evaluate the effects of heat processing on the antifungal activity of honey. Methods: A sample of the honey of eucalyptus was divided into four portions of 250 g each. One of the four portions obtained from studied honey was not heated (not heated fraction 25曟, the other portions were placed in water bath during 24 hours at 40 曟, 60 曟 and 80曟 temperatures. The HMF rates, Acidity, pH and the index of refraction were determined by harmonized methods. The antifungal tests (Minimum Inhibitory Concentration were carried out on Sabouraud agar medium embedded with honey according to dilution test. Results: The moisture shows values of 15.65% and 15.83%, pH between 4.10 and 4.24, the free acidity ranges between 33.8 and 38.36 meq kg-1, hydroxymethylfurfural (HMF content shows values between 28.8 and 103.44 mg kg-1. The antifungal action of the non-heated fraction (Fc of honey in vitro was marked 40 % (vol/vol than heated fractions of honey (42%, 44%, and 45% vol/vol. respectively The antifungal activity of each fraction decreased in the following order: Fct曘 25 > Fct曘 40 > Fct曘 60 > Fct曘 80]. Conclusion: our findings indicate that different levels of parameters physical-chemical properties of honey to different temperatures showed inhibitory activity against C. albicans with variable degrees.

Heat pumps: heat recovery

Energy Technology Data Exchange (ETDEWEB)

Pielke, R

1976-01-01

The author firstly explains in a general manner the functioning of the heat pump. Following a brief look at the future heat demand and the possibilities of covering it, the various methods of obtaining energy (making use of solar energy, ground heat, and others) and the practical applications (office heating, swimming pool heating etc.) are explained. The author still sees considerable difficulties in using the heat pump at present on a large scale. Firstly there is not enough maintenance personnel available, secondly the electricity supply undertakings cannot provide the necessary electricity on a wide basis without considerable investments. Other possibilities to save energy or to use waste energy are at present easier and more economical to realize. Recuperative and regenerative systems are described.

Browse Title Index

African Journals Online (AJOL)

Items 801 - 850 of 1011 ... ... heat transfer enhancement methods applied in parabolic trough ... Vol 35, No 2 (2016), REVIEW OF WIRELESS MIMO CHANNEL ... Vol 17, No 1 (1996), Simulation of Electromagnetic Transients in Power Systems ...

Modelling and analysis of radial thermal stresses and temperature ...

African Journals Online (AJOL)

user

The temperature field, heat transfer rate and thermal stresses were investigated with numerical simulation models using FORTRAN FE (finite element) software. ...... specific heats, International Communications in Heat and Mass Transfer, Vol.

New waste heat district heating system with combined heat and power based on absorption heat exchange cycle in China

International Nuclear Information System (INIS)

Sun Fangtian; Fu Lin; Zhang Shigang; Sun Jian

2012-01-01

A new waste heat district heating system with combined heat and power based on absorption heat exchange cycle (DHAC) was developed to increase the heating capacity of combined heat and power (CHP) through waste heat recovery, and enhance heat transmission capacity of the existing primary side district heating network through decreasing return water temperature by new type absorption heat exchanger (AHE). The DHAC system and a conventional district heating system based on CHP (CDH) were analyzed in terms of both thermodynamics and economics. Compared to CDH, the DHAC increased heating capacity by 31% and increased heat transmission capacity of the existing primary side district heating network by 75%. The results showed that the exergetic efficiency of DHAC was 10.41% higher and the product exergy monetary cost was 36.6¥/GJ less than a CHD. DHAC is an effective way to increase thermal utilization factor of CHP, and to reduce district heating cost. - Highlights: ► Absorption heat pumps are used to recover waste heat in CHP. ► Absorption heat exchanger can reduce exergy loss in the heat transfer process. ► New waste heat heating system (DHAC) can increase heating capacity of CHP by 31%. ► DHAC can enhance heat transmission capacity of the primary pipe network by 75%. ► DHAC system has the higher exergetic efficiency and the better economic benefit.

Heating systems for heating subsurface formations

Science.gov (United States)

Nguyen, Scott Vinh [Houston, TX; Vinegar, Harold J [Bellaire, TX

2011-04-26

Methods and systems for heating a subsurface formation are described herein. A heating system for a subsurface formation includes a sealed conduit positioned in an opening in the formation and a heat source. The sealed conduit includes a heat transfer fluid. The heat source provides heat to a portion of the sealed conduit to change phase of the heat transfer fluid from a liquid to a vapor. The vapor in the sealed conduit rises in the sealed conduit, condenses to transfer heat to the formation and returns to the conduit portion as a liquid.

Heat pipe heat exchanger for heat recovery in air conditioning

Energy Technology Data Exchange (ETDEWEB)

Abd El-Baky, Mostafa A.; Mohamed, Mousa M. [Mechanical Power Engineering Department, Faculty of Engineering, Minufiya University, Shebin El-Kom (Egypt)

2007-03-15

The heat pipe heat exchangers are used in heat recovery applications to cool the incoming fresh air in air conditioning applications. Two streams of fresh and return air have been connected with heat pipe heat exchanger to investigate the thermal performance and effectiveness of heat recovery system. Ratios of mass flow rate between return and fresh air of 1, 1.5 and 2.3 have been adapted to validate the heat transfer and the temperature change of fresh air. Fresh air inlet temperature of 32-40{sup o}C has been controlled, while the inlet return air temperature is kept constant at about 26{sup o}C. The results showed that the temperature changes of fresh and return air are increased with the increase of inlet temperature of fresh air. The effectiveness and heat transfer for both evaporator and condenser sections are also increased to about 48%, when the inlet fresh air temperature is increased to 40{sup o}C. The effect of mass flow rate ratio on effectiveness is positive for evaporator side and negative for condenser side. The enthalpy ratio between the heat recovery and conventional air mixing is increased to about 85% with increasing fresh air inlet temperature. The optimum effectiveness of heat pipe heat exchanger is estimated and compared with the present experimental data. The results showed that the effectiveness is close to the optimum effectiveness at fresh air inlet temperature near the fluid operating temperature of heat pipes. (author)

Laser Beam Shaping XIII, Proceedings of SPIE Vol. 8490

CSIR Research Space (South Africa)

Forbes, A

2012-09-01

Full Text Available .1117/12.2013615 Proc. of SPIE Vol. 8490 849001-1 Downloaded From: http://proceedings.spiedigitallibrary.org/ on 10/17/2012 Terms of Use: http://spiedl.org/terms The papers included in this volume were part of the technical conference cited on the cover and title..., Bellingham, Washington 98227-0010 USA Telephone +1 360 676 3290 (Pacific Time)? Fax +1 360 647 1445 SPIE.org Copyright ? 2012, Society of Photo-Optical Instrumentation Engineers. Copying of material in this book for internal or personal use...

A new correlation for convective heat transfer coefficient of water–alumina nanofluid in a square array subchannel under PWR condition

Energy Technology Data Exchange (ETDEWEB)

Shamim, Jubair A. [Department of Nuclear Engineering, Seoul National University, Seoul 08826 (Korea, Republic of); Department of Mechanical Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Bhowmik, Palash K. [Department of Nuclear Engineering, Seoul National University, Seoul 08826 (Korea, Republic of); Department of Nuclear Engineering, Missouri University of Science and Technology, 1201 N. State St., Rolla, MO 65409 (United States); Xiangyi, Chen [Department of Nuclear Engineering, Seoul National University, Seoul 08826 (Korea, Republic of); Suh, Kune Y., E-mail: kysuh@snu.ac.kr [Department of Nuclear Engineering, Seoul National University, Seoul 08826 (Korea, Republic of)

2016-11-15

Highlights: • Thermo-hydrodynamic properties of water–Al{sub 2}O{sub 3} nanofluid at PWR condition is analyzed. • Details of CFD simulation and validation procedure is outlined. • Augmented heat transfer capacity of nanofluid is governed by larger pumping power. • A new correlation for nanofluid Nusselt number in subchannel geometry is proposed. - Abstract: The computational fluid dynamic (CFD) simulation is performed to determine on the thermo- and hydrodynamic performance of the water–alumina (Al{sub 2}O{sub 3}) nanofluid in a square array subchannel featuring pitch-to-diameter ratios of 1.25 and 1.35. Two fundamental aspects of thermal hydraulics, viz. heat transfer and pressure drop, are assessed under typical pressurized water reactor (PWR) conditions at various flow rates (3 × 10{sup 5} ⩽ Re ⩽ 6 × 10{sup 5}) using pure water and differing concentrations of water–alumina nanofluid (0.5–3.0 vol.%) as coolant. Numerical results are compared against predictions made by conventional single-phase convective heat transfer and pressure loss correlations for fully developed turbulent flow. It is observed that addition of tiny nanoparticles in PWR coolant can give rise to the convective heat transfer coefficient at the expense of larger pressure drop. Nevertheless, a modified correlation as a function of nanoparticle volume fraction is proposed to estimate nanofluid Nusselt number more precisely in square array subchannel.

A new correlation for convective heat transfer coefficient of water–alumina nanofluid in a square array subchannel under PWR condition

International Nuclear Information System (INIS)

Shamim, Jubair A.; Bhowmik, Palash K.; Xiangyi, Chen; Suh, Kune Y.

2016-01-01

Highlights: • Thermo-hydrodynamic properties of water–Al_2O_3 nanofluid at PWR condition is analyzed. • Details of CFD simulation and validation procedure is outlined. • Augmented heat transfer capacity of nanofluid is governed by larger pumping power. • A new correlation for nanofluid Nusselt number in subchannel geometry is proposed. - Abstract: The computational fluid dynamic (CFD) simulation is performed to determine on the thermo- and hydrodynamic performance of the water–alumina (Al_2O_3) nanofluid in a square array subchannel featuring pitch-to-diameter ratios of 1.25 and 1.35. Two fundamental aspects of thermal hydraulics, viz. heat transfer and pressure drop, are assessed under typical pressurized water reactor (PWR) conditions at various flow rates (3 × 10"5 ⩽ Re ⩽ 6 × 10"5) using pure water and differing concentrations of water–alumina nanofluid (0.5–3.0 vol.%) as coolant. Numerical results are compared against predictions made by conventional single-phase convective heat transfer and pressure loss correlations for fully developed turbulent flow. It is observed that addition of tiny nanoparticles in PWR coolant can give rise to the convective heat transfer coefficient at the expense of larger pressure drop. Nevertheless, a modified correlation as a function of nanoparticle volume fraction is proposed to estimate nanofluid Nusselt number more precisely in square array subchannel.

Future heat supply of our cities. Heating by waste heat

Energy Technology Data Exchange (ETDEWEB)

Brachetti, H E [Stadtwerke Hannover A.G. (Germany, F.R.); Technische Univ. Hannover (Germany, F.R.))

1976-08-01

The energy-price crisis resulted in structural changes of the complete energy supply and reactivated the question of energy management with respect to the optimum solution of meeting the energy requirements for space heating. Condensation power plants are increasingly replaced by thermal stations, the waste heat of which is used as so-called district heat. Thermal power stations must be situated close to urban areas. The problem of emission of harmful materials can partly be overcome by high-level emission. The main subject of the article, however, is the problem of conducting and distributing the heat. The building costs of heat pipeline systems and the requirements to be met by heat pipelines such as strength, heat insulation and protection against humidity and ground water are investigated.

Bulletin of Animal Health and Production in Africa - Vol 66, No 1 (2018)

African Journals Online (AJOL)

AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING ... Bulletin of Animal Health and Production in Africa - Vol 66, No 1 (2018) ... Performance and haematological parameters of growing rabbits fed different levels of ... Association of smallholder dairy farmers management and milking practices with ...

Hydride heat pump with heat regenerator

Science.gov (United States)

Jones, Jack A. (Inventor)

1991-01-01

A regenerative hydride heat pump process and system is provided which can regenerate a high percentage of the sensible heat of the system. A series of at least four canisters containing a lower temperature performing hydride and a series of at least four canisters containing a higher temperature performing hydride is provided. Each canister contains a heat conductive passageway through which a heat transfer fluid is circulated so that sensible heat is regenerated. The process and system are useful for air conditioning rooms, providing room heat in the winter or for hot water heating throughout the year, and, in general, for pumping heat from a lower temperature to a higher temperature.

A background risk analysis. Vol. 1

International Nuclear Information System (INIS)

Taylor, J.R.

1979-01-01

This 4-volumes report gives a background of ideas, principles, and examples which might be of use in developing practical methods for risk analysis. Some of the risk analysis techniques, described are somewhat experimental. The report is written in an introductory style, but where some point needs further justification or evaluation, this is given in the form of a chapter appendix. In this way, it is hoped that the report can serve two purposes, - as a basis for starting risk analysis work and as a basis for discussing effectiveness of risk analysis procedures. The report should be seen as a preliminary stage, prior to a program of industrial trials of risk analysis methods. Vol. 1 contains a short history of risk analysis, and chapters on risk, failures, errors and accidents, and general procedures for risk analysis. (BP)

Industrial waste heat for district heating

International Nuclear Information System (INIS)

Heitner, K.L.; Brooks, P.P.

1982-01-01

Presents 2 bounding evaluations of industrial waste heat availability. Surveys waste heat from 29 major industry groups at the 2-digit level in Standard Industrial Codes (SIC). Explains that waste heat availability in each industry was related to regional product sales, in order to estimate regional waste heat availability. Evaluates 4 selected industries at the 4-digit SIC level. Finds that industrial waste heat represents a significant energy resource in several urban areas, including Chicago and Los Angeles, where it could supply all of these areas residential heating and cooling load. Points out that there is a strong need to evaluate the available waste heat for more industries at the 4-digit level. Urges further studies to identify other useful industrial waste heat sources as well as potential waste heat users

Mapping of potential heat sources for heat pumps for district heating in Denmark

International Nuclear Information System (INIS)

Lund, Rasmus; Persson, Urban

2016-01-01

The ambitious policy in Denmark on having a 100% renewable energy supply in 2050 requires radical changes to the energy systems to avoid an extensive and unsustainable use of biomass resources. Currently, wind power is being expanded and the increasing supply of electricity is slowly pushing the CHP (combined heat and power) plants out of operation, reducing the energy efficiency of the DH (district heating) supply. Here, large heat pumps for district heating is a frequently mentioned solution as a flexible demand for electricity and an energy efficient heat producer. The idea is to make heat pump use a low temperature waste or ambient heat source, but it has so far been very unclear which heat sources are actually available for this purpose. In this study eight categories of heat sources are analysed for the case of Denmark and included in a detailed spatial analysis where the identified heat sources are put in relation to the district heating areas and the corresponding demands. The analysis shows that potential heat sources are present near almost all district heating areas and that sea water most likely will have to play a substantial role as a heat source in future energy systems in Denmark. - Highlights: • The availability of heat sources for heat pumps in Denmark are mapped and quantified. • A novel methodology for assessment of low temperature industrial excess heat is presented. • There are heat sources available for 99% of district heating networks in Denmark. • The concentration of heat sources is generally bigger around bigger cities than smaller. • Ambient temperature heat sources will be more needed in district heating of big cities.

Browse Title Index

African Journals Online (AJOL)

Items 251 - 300 of 1255 ... Vol 13, No 1 (2007), Central defference approximation of heat function in forced ... Vol 16, No 3 (2010), Chemical and mineralogical characteristics of ... Chemical profile of the endocarp and exocarp of yellow monkey ...

Retraction: On the origin of power-law distributions in systems with constrained phase space [Condens. Matter Phys., 2013, vol. 16, 43802

Directory of Open Access Journals (Sweden)

Editorial Board

2014-03-01

Full Text Available The article Condens. Matter Phys., 2013, vol. 16, 43802 ( DOI:10.5488/CMP.16.43802 has been retracted by the decision of the Editorial Board. There is a significant overlap with an article: Phys. Rev. E, 2006, vol. 74, 036120 ( DOI:10.1103/PhysRevE.74.036120. Appologies are offered to readers of the journal that this was not detected during the submission process.

A background to risk analysis. Vol. 4

International Nuclear Information System (INIS)

Taylor, J.R.

1979-01-01

This 4-volumes report gives a background of ideas, principles, and examples which might be of use in developing practical methods for risk analysis. Some of the risk analysis techniques described are somewhat experimental. The report is written in an introductory style, but where some point needs further justification or evaluation, this is given in the form of a chapter appendix. In this way, it is hoped that the report can serve two purposes, - as a basis for starting risk analysis work and as a basis for discussing effectiveness of risk analysis procedures. The report should be seen as a preliminary stage, prior to a program of industrial trials of risk analysis methods. Vol. 4 treats human error in plant operation. (BP)

A background to risk analysis. Vol. 2

International Nuclear Information System (INIS)

Taylor, J.R.

1979-01-01

This 4-volumes report gives a background of ideas, principles and examples which might be of use in developing practical methods for risk analysis. Some of the risk analysis techniques described are somewhat experimental. The report is written in an introductory style, but where some point needs further justification or evaluation, this is given in the form of a chapter appendix. In this way, it is hoped that the report can serve two purposes, - as a basis for starting risk analysis work and as a basis for discussing effectiveness of risk analysis procedures. The report should be seen as a preliminary stage, prior to a program of industrial trials of risk analysis methods. Vol. 2 treats generic methods of qualitative failure analysis. (BP)

Recycling of hazardous solid waste material using high-temperature solar process heat

Energy Technology Data Exchange (ETDEWEB)

Schaffner, B.; Meier, A.; Wuillemin, D.; Hoffelner, W.; Steinfeld, A.

2003-03-01

A novel high-temperature solar chemical reactor is proposed for the thermal recycling of hazardous solid waste material using concentrated solar power. A 10 kW solar reactor prototype was designed and tested for the carbothermic reduction of electric arc furnace dusts (EAFD). The reactor was subjected to mean solar flux intensities of 2000 kW/m2 and operated in both batch and continuous mode within the temperature range 1120-1400 K. Extraction of up to 99% and 90% of the Zn originally contained in the EAFD was achieved in the residue for the batch and continuous solar experiments, respectively. The condensed off-gas products consisted mainly of Zn, Pb, and Cl. No ZnO was detected when the O{sub 2} concentration remained below 2 vol.-%. The use of concentrated solar energy as the source of process heat offers the possibility of converting hazardous solid waste material into valuable commodities for processes in closed and sustainable material cycles. (author)

Fiber Orientation Effects in Fused Filament Fabrication of Air-Cooled Heat Exchangers

Science.gov (United States)

Mulholland, T.; Goris, S.; Boxleitner, J.; Osswald, T. A.; Rudolph, N.

2018-03-01

Fused filament fabrication (FFF) is a type of additive manufacturing based on material extrusion that has long been considered a prototyping technology. However, the right application of material, process, and product can be used for manufacturing of end-use products, such as air-cooled heat exchangers made by adding fillers to the base polymer, enhancing the thermal conductivity. Fiber fillers lead to anisotropic thermal conductivity, which is governed by the process-induced fiber orientation. This article presents an experimental study on the microstructure-property relationship for carbon fiber-filled polyamide used in FFF. The fiber orientation is measured by micro-computed tomography, and the thermal conductivity of manufactured samples is measured. Although the thermal conductivity is raised by more than three times in the fiber orientation direction at a load of only 12 vol.%, the enhancement is low in the other directions, and this anisotropy, along with certain manufacturing restrictions, influences the final part performance.

Review: heat pipe heat exchangers at IROST

OpenAIRE

E. Azad

2012-01-01

The use of the heat pipe as a component in a heat recovery device has gained worldwide acceptance. Heat pipes are passive, highly reliable and offer high heat transfer rates. This study summarizes the investigation of different types of heat pipe heat recovery systems (HPHRSs). The studies are classified on the basis of the type of the HPHRS. This research is based on 30 years of experience on heat pipe and heat recovery systems that are presented in this study. Copyright , Oxford University ...

Targeting the maximum heat recovery for systems with heat losses and heat gains

International Nuclear Information System (INIS)

Wan Alwi, Sharifah Rafidah; Lee, Carmen Kar Mun; Lee, Kim Yau; Abd Manan, Zainuddin; Fraser, Duncan M.

2014-01-01

Graphical abstract: Illustration of heat gains and losses from process streams. - Highlights: • Maximising energy savings through heat losses or gains. • Identifying location where insulation can be avoided. • Heuristics to maximise heat losses or gains. • Targeting heat losses or gains using the extended STEP technique and HEAT diagram. - Abstract: Process Integration using the Pinch Analysis technique has been widely used as a tool for the optimal design of heat exchanger networks (HENs). The Composite Curves and the Stream Temperature versus Enthalpy Plot (STEP) are among the graphical tools used to target the maximum heat recovery for a HEN. However, these tools assume that heat losses and heat gains are negligible. This work presents an approach that considers heat losses and heat gains during the establishment of the minimum utility targets. The STEP method, which is plotted based on the individual, as opposed to the composite streams, has been extended to consider the effect of heat losses and heat gains during stream matching. Several rules to guide the proper location of pipe insulation, and the appropriate procedure for stream shifting have been introduced in order to minimise the heat losses and maximise the heat gains. Application of the method on two case studies shows that considering heat losses and heat gains yield more realistic utility targets and help reduce both the insulation capital cost and utility cost of a HEN

Heating networks and domestic central heating systems

Energy Technology Data Exchange (ETDEWEB)

Kamler, W; Wasilewski, W

1976-08-01

This is a comprehensive survey of the 26 contributions from 8 European countries submitted to the 3rd International District Heating Conference in Warsaw held on the subject 'Heating Networks and Domestic Central Heating Systems'. The contributions are grouped according to 8 groups of subjects: (1) heat carriers and their parameters; (2) system of heating networks; (3) calculation and optimization of heating networks; (4) construction of heating networks; (5) operation control and automation; (6) operational problems; (7) corrosion problems; and (8) methods of heat accounting.

Heat transfer and critical heat flux in a asymmetrically heated tube helicoidal flow

International Nuclear Information System (INIS)

Boscary, J.

1995-10-01

The design of plasma facing components is crucial for plasma performance in next fusion reactors. These elements will be submitted to very high heat flux. They will be actively water-cooled by swirl tubes in the subcooled boiling regime. High heat flux experiments were conducted in order to analyse the heat transfer and to evaluate the critical heat flux. Water-cooled mock-ups were one-side heated by an electron beam gun for different thermal-hydraulic conditions. The critical heat flux was detected by an original method based on the isotherm modification on the heated surface. The wall heat transfer law including forced convection and subcooled boiling regimes was established. Numerical calculations of the material heat transfer conduction allowed the non-homogeneous distribution of the wall temperature and of the wall heat flux to be evaluated. The critical heat flux value was defined as the wall maximum heat flux. A critical heat flux model based on the liquid sublayer dryout under a vapor blanket was established. A good agreement with test results was found. (author). 198 refs., 126 figs., 21 tabs

Industrial excess heat for district heating in Denmark

International Nuclear Information System (INIS)

Bühler, Fabian; Petrović, Stefan; Karlsson, Kenneth; Elmegaard, Brian

2017-01-01

Highlights: •Method for utilisation potential of industrial excess heat for district heating. •Industrial excess heat from thermal processes is quantified at single production units. •Linking of industrial excess heat sources and district heating demands done in GIS. •Excess heat recovery using direct heat transfer and heat pumps. •5.1% of the Danish district heating demand could be supplied by industrial excess heat. -- Abstract: Excess heat is available from various sources and its utilisation could reduce the primary energy use. The accessibility of this heat is however dependent amongst others on the source and sink temperature, amount and potential users in its vicinity. In this work a new method is developed which analyses excess heat sources from the industrial sector and how they could be used for district heating. This method first allocates excess heat to single production units by introducing and validating a new approach. Spatial analysis of the heat sources and consumers are then performed to evaluate the potential for using them for district heating. In this way the theoretical potential of using the excess heat for covering the heating demand of buildings is determined. Through the use of industry specific temperature profiles the heat usable directly or via heat pumps is further found. A sensitivity analysis investigates the impact of future energy efficiency measures in the industry, buildings and the district heating grid on the national potential. The results show that for the case study of Denmark, 1.36 TWh of district heat could be provided annually with industrial excess heat from thermal processes which equals 5.1% of the current demand. More than half of this heat was found to be usable directly, without the need for a heat pump.

Clusters in Nuclei. Vol. 2

International Nuclear Information System (INIS)

Beck, Christian

2012-01-01

Following the pioneering discovery of alpha clustering and of molecular resonances, the field of nuclear clustering is today one of those domains of heavy-ion nuclear physics that faces the greatest challenges, yet also contains the greatest opportunities. After many summer schools and workshops, in particular over the last decade, the community of nuclear molecular physicists has decided to collaborate in producing a comprehensive collection of lectures and tutorial reviews covering the field. This second volume follows the successful Lect. Notes Phys. 818 (Vol.1), and comprises six extensive lectures covering the following topics: - Microscopic cluster models - Neutron halo and break-up reactions - Break-up reaction models for two- and three-cluster projectiles - Clustering effects within the di-nuclear model - Nuclear alpha-particle condensates - Clusters in nuclei: experimental perspectives By promoting new ideas and developments while retaining a pedagogical style of presentation throughout, these lectures will serve as both a reference and an advanced teaching manual for future courses and schools in the fields of nuclear physics and nuclear astrophysics. (orig.)

Clusters in Nuclei. Vol. 2

Energy Technology Data Exchange (ETDEWEB)

Beck, Christian (ed.) [Strasbourg Univ. (France). Inst. Pluridiciplinaire Hubert Curien

2012-07-01

Following the pioneering discovery of alpha clustering and of molecular resonances, the field of nuclear clustering is today one of those domains of heavy-ion nuclear physics that faces the greatest challenges, yet also contains the greatest opportunities. After many summer schools and workshops, in particular over the last decade, the community of nuclear molecular physicists has decided to collaborate in producing a comprehensive collection of lectures and tutorial reviews covering the field. This second volume follows the successful Lect. Notes Phys. 818 (Vol.1), and comprises six extensive lectures covering the following topics: - Microscopic cluster models - Neutron halo and break-up reactions - Break-up reaction models for two- and three-cluster projectiles - Clustering effects within the di-nuclear model - Nuclear alpha-particle condensates - Clusters in nuclei: experimental perspectives By promoting new ideas and developments while retaining a pedagogical style of presentation throughout, these lectures will serve as both a reference and an advanced teaching manual for future courses and schools in the fields of nuclear physics and nuclear astrophysics. (orig.)

Neutron Thermalization and Reactor Spectra. Vol. II. Proceedings of the Symposium on Neutron Thermalization and Reactor Spectra

International Nuclear Information System (INIS)

1968-01-01

Proceedings of a Symposium organized by the IAEA and held at Ann Arbor, Michigan, USA, 17 - 21 July 1967. The meeting was attended by 143 participants from 24 Member States and one international organization. Contents: (Vol.I) Theory of neutron thermalization (15 papers); Scattering law (20 papers); Angular, space, temperature and time dependence of neutron spectra (9 papers). (Vol.II) Measurement of thermal neutron spectra and spectral indices, and comparison with theory (17 papers); Time-dependent problems in neutron thermalization (12 papers). Each paper is in its original language (61 English, 1 French and 11 Russian) and is preceded by an abstract in English with one in the original language if this is not English. Discussions are in English.

Compuestos volátiles libres y enlazados glicosídicamente en la pulpa de la uva Caimarona (Pourouma cecropiifolia Mart. Compostos voláteis livres e enlaçados glicosídicamente na polpa da uva Caimarona (Pourouma cecropiifolia Mart.

Directory of Open Access Journals (Sweden)

Juliana Constanza Barrios Guio

2010-03-01

Full Text Available Los componentes volátiles presentes en la pulpa de la uva Caimarona se estudiaron mediante GC-MS. Éstos se extrajeron por tres técnicas: evaporación del aroma asistida con solvente (Solvent Assisted Flavour Evaporation SAFE, extracción continua líquido-líquido (LL y destilación por arrastre con vapor-extracción simultanea con solvente orgánico (DES. En general los componentes volátiles predominantes en la pulpa fueron alcoholes alifáticos y terpénicos. Las notas olfativas del extracto SAFE fueron descritas como floral tenue y verde herbal similares a las exhibidas por la pulpa fresca. Este extracto presentó como componentes mayoritarios linalol 1,2-propanodiol y salicilato de metilo. En contraste, el extracto LL presentó notas que recuerdan la uva pasa y el vino moscatel y sus componentes mayoritarios fueron el ácido acético, el salicilato de metilo y el 2,6-dimetil-2(Z,7-octadien-1,6-diol. El extracto DES fue descrito con notas fresca, floral, cereal y amargo y está constituido por un reducido número de componentes mostrando el efecto negativo de la temperatura en la extracción; sus componentes mayoritarios fueron 1,2-propanodiol, linalol y salicilato de metilo. Adicionalmente, los componentes volátiles mayoritarios liberados por hidrólisis enzimática (Rohapect D5L de los glicósidos de la pulpa fueron ácido acético, ácido benzoico y vainillina. Cabe destacar que aunque el linalol no se encontró entre las agliconas volátiles, se detectaron los dioles biogenéticamente relacionados: 3,7-dimetil-1,5-octadien-3,7-diol y los isómeros E y Z del 2,6-dimetil-2,7-octadien-1,6-diol.Os componentes voláteis presentes na polpa da uva Caimarona foram estudados mediante GC-MS. Estes foram extraídos por três técnicas: evaporação de aroma assistida com solvente (Solvent Assisted Flavour Evaporation SAFE, extração continua líquido-líquido (LL e destilação por arraste com vapor-extração simultânea com solvente org

Investigations on the behaviour of reactor pressure vessel material 20 MnMoNi 55 during heat and stress relieving treatments. Vol. 1 and 2

International Nuclear Information System (INIS)

Blind, D.; Schroeder-Obst, D.; Herz, K.; Maidorn, C.

1984-01-01

Variation of various heat treatment parameters with regard to forging, hardening, tempering and stress-relieving has been applied to several heats of pressure vessel steels with the aim of testing the possibility to obtain higher notch impact energy values. On one hand the variation of heat treatment parameters within the limits of the current VdTUeV material sheet 401/4 5.80 did not result in outstanding improvements of toughness. On the other hand, when employing procedures which did not correspond to the specifications, e.g. tempering up to 100 h, an evident decrease of the upper shelf and an increase of the transition temperature could be observed. Nevertheless, the specified values were generally reached. Essentially, the observations on the test materials confirm, apart from a few exceptions, the positive practical experience with the material 20 MnMoNi 5 5. Based on these relations between thoughness and forging as well as heat treatment the manufacturer obtained, in accordance with the current research program, an outstanding improvement of toughness by means of various optimization measures which had the effect of optimal, evidently increased upper shelfs and which excluded difficulties concerning acceptance criteria, e.g. too high notch impact energy transition temperatures. (orig./IHOE) [de

Componentes volátiles de mamey (mammea americana L.

Directory of Open Access Journals (Sweden)

Alicia Lucía Morales

2010-07-01

Full Text Available Los componentes volátiles del aroma de mamey (Mammea americana L, fueron extraídos utilizando el método de destilación por arrastre con vapor-extracción simultánea con solvente orgánico. El extracto fue prefraccionado por cromatografía en columna en silica gel con gradiente discontinuo Pentano: Éter etílico para obtener tres fracciones que fueron analizadas por CGAR y CGAR-EM. Se detectaron 34 compuestos, de los cuales fueron identificados 22, siendo los componentes mayoritarios: Furfural (7281 ^ig/kg y E-Famesol (2145 ng/kg

Constituyentes volátiles del mango de azúcar

OpenAIRE

Bautista., Edgar; Duque, Carmenza; Torres, Rafael

2010-01-01

Empleando Extracción de Volátiles por Espacio de Cabeza Dinámico y Extracción Líquido-Líquido, se estudió el aroma del mango de azúcar (Mangifera indica L), variedad nativa Colombiana apreciada por su exquisito aroma y sabor. Estos dos métodos complementarios permifieron la identificación, por Cromatografía de Gases de Alta resolución y Cromatografía de Gases de Alta Resolución - Espectrometría de Masas, de 52 coinponentes, entre los cuales sobresalieron como mayoritarios el 3-careno, el b...

Effect of dispersion parameters on the consolidation of starch-loaded hydroxyapatite slurry

Directory of Open Access Journals (Sweden)

Yasser M.Z. Ahmed

2014-09-01

Full Text Available The influence of some parameters controlling the hydroxyapatite (HA suspension rheology in terms of heat treatment of the HA powder prior to suspension preparation, suspension solid loading and the amount of corn starch addition was thoroughly investigated. The heat treatment of powder at 1100 °C prior to suspension preparation was found to be extremely efficient in preparing suspensions with high solid loading of 59 vol.%. In contrast, the highest solid loading that could be developed from the non-heat treated powder was 14 vol.%. This phenomenon is consequence of the changes in the physical and chemical properties of the powder after the heat treatment step. The amount of native corn starch addition has ranged from 10 to 40 vol.%. The addition of corn starch leads to the high retardation in the suspension viscosity, particularly at low shear rate. On the contrary, at higher shear rate the situation is completely different. The properties of the consolidated green sample (produced from suspensions containing various corn starch amounts in terms of relative density and compressive strength were studied. The results indicated that even though there were no considerable changes in the relative density, the compressive strength was sharply increased with increasing starch amount content until it reached a maximum at 30 vol.% and then decreased thereafter.

Soil-structure interaction Vol.2. Influence of lift-off

International Nuclear Information System (INIS)

Miller, C.A.

1986-04-01

This study has been performed for the Nuclear Regulatory Commission (NRC) by the Structural Analysis Division of Brookhaven National Laboratory (BNL). The study was conducted during the fiscal year 1985 on the program entitled 'Benchmarking of Structural Engineering Problems' sponsored by NRC. The program considered three separate but complementary problems, each associated with the soil-structure interaction (SSI) phase of the seismic response analysis of nuclear plant facilities. The reports are presented in three separate volumes. The general title for the reports is 'Soil Structure Interaction' with the following subtitles: Vol. 1 Influence of Layering by A.J. Philippacopoulos, Vol. 2 Influence of Lift-Off by C.A. Miller, Vol. 3 Influence of Ground Water by C.J. Costantino. The two problems presented in Volumes 2 and 3 were conducted at the City University of New York (CUNY) under subcontract to BNL. This report, Volume 2 of the report, presents a summary of the work performed defining the influence liftoff has on the seismic response of nuclear power plant structures. The standard lumped parameter analysis method was modified by representing the lumped soil/structure interaction horizontal and rocking dampers with distributed (over the foundation area) springs and dampers. The distributed springs and dampers are then modified so that they can only transmit compressive stresses. Additional interaction damping is included to account for the energy dissipated as a portion of the foundation which has separated comes back into contact with the soil. The validity of the model is evaluated by comparing predictions made with it to data measured during the SIMQUAKE II experiment. The predictions were found to correlate quite well with the measured data except for some discrepancies at the higher frequencies (greater than 10 cps). This discrepancy was attributed to the relatively crude model used for impact effects. Data is presented which identifies the peak

Heat Transfer Characteristics of SiC-coated Heat Pipe for Passive Decay Heat Removal

International Nuclear Information System (INIS)

Kim, Kyung Mo; Kim, In Guk; Jeong, Yeong Shin; Bang, In Cheol

2014-01-01

The main concern with the Fukushima accident was the failure of active and passive core cooling systems. The main function of existing passive decay heat removal systems is feeding additional coolant to the reactor core. Thus, an established emergency core cooling system (ECCS) cannot operate properly because of impossible depressurization under the station blackout (SBO) condition. Therefore, a new concept for passive decay heat removal system is required. In this study, an innovative hybrid control rod concept is considered for passive in-core decay heat removal that differs from the existing direct vessel injection core cooling system and passive auxiliary feedwater system (PAFS). The heat transfer between the evaporator and condenser sections occurs by phase change of the working fluid and capillary action induced by wick structures installed on the inner wall of the heat pipe. In this study, a hybrid control rod is developed to take the roles of both neutron absorption and heat removal by combining the functions of a heat pipe and control rod. Previous studies on enhancing the heat removal capacity of heat pipes used nanofluids, self-rewetting fluids, various wick structures and condensers. Many studies have examined the thermal performances of heat pipes using various nanofluids. They concluded that the enhanced thermal performance of the heat pipe using nanofluids is due to nanoparticle deposition on the wick structures. Thus, the wick structure of heat pipes has been modified by nanoparticle deposition to enhance the heat removal capacity. However, previous studies used relatively small heat pipes and narrow ranges of heat loads. The environment of a nuclear reactor is very specific, and the decay heat produced by fission products after shutdown is relatively large. Thus, this study tested a large-scale heat pipe over a wide range of power. The concept of a hybrid heat pipe for an advanced in-core decay heat removal system was introduced for complete

Heat Transfer Characteristics of SiC-coated Heat Pipe for Passive Decay Heat Removal

Energy Technology Data Exchange (ETDEWEB)

Kim, Kyung Mo; Kim, In Guk; Jeong, Yeong Shin; Bang, In Cheol [Ulsan National Institute of Science and Technology, Ulsan (Korea, Republic of)

2014-10-15

The main concern with the Fukushima accident was the failure of active and passive core cooling systems. The main function of existing passive decay heat removal systems is feeding additional coolant to the reactor core. Thus, an established emergency core cooling system (ECCS) cannot operate properly because of impossible depressurization under the station blackout (SBO) condition. Therefore, a new concept for passive decay heat removal system is required. In this study, an innovative hybrid control rod concept is considered for passive in-core decay heat removal that differs from the existing direct vessel injection core cooling system and passive auxiliary feedwater system (PAFS). The heat transfer between the evaporator and condenser sections occurs by phase change of the working fluid and capillary action induced by wick structures installed on the inner wall of the heat pipe. In this study, a hybrid control rod is developed to take the roles of both neutron absorption and heat removal by combining the functions of a heat pipe and control rod. Previous studies on enhancing the heat removal capacity of heat pipes used nanofluids, self-rewetting fluids, various wick structures and condensers. Many studies have examined the thermal performances of heat pipes using various nanofluids. They concluded that the enhanced thermal performance of the heat pipe using nanofluids is due to nanoparticle deposition on the wick structures. Thus, the wick structure of heat pipes has been modified by nanoparticle deposition to enhance the heat removal capacity. However, previous studies used relatively small heat pipes and narrow ranges of heat loads. The environment of a nuclear reactor is very specific, and the decay heat produced by fission products after shutdown is relatively large. Thus, this study tested a large-scale heat pipe over a wide range of power. The concept of a hybrid heat pipe for an advanced in-core decay heat removal system was introduced for complete

Optimal usage of low temperature heat sources to supply district heating by heat pumps

DEFF Research Database (Denmark)

Pieper, Henrik; Ommen, Torben Schmidt; Markussen, Wiebke Brix

2017-01-01

This paper presents a theoretical study on the optimal usage of different low temperature heat sources to supply district heating by heat pumps. The study is based on data for the Copenhagen region. The heat sources were prioritized based on the coefficient of performance calculated for each hour...... and the covered demand of each heat source as well as required peak unit capacity. The results showed that heat pumps using different heat sources yield better performance than a heat pump based on a single one. The performance was influenced by the composition of the different heat sources. It was found that 78......% groundwater, 22% seawater and 0% air resulted in highest COP of 3.33 for the given heat demand. Furthermore, the implementation of rule based short term storage made peak units redundant. The variation in base load capacity showed that heat pumps utilizing the analyzed heat sources could perform very...

Solar Heating System with Building-Integrated Heat Storage

DEFF Research Database (Denmark)

Heller, Alfred

1996-01-01

Traditional solar heating systems cover between 5 and 10% of the heat demand fordomestic hot water and comfort heating. By applying storage capacity this share can beincreased much. The Danish producer of solar heating systems, Aidt-Miljø, markets such a system including storage of dry sand heated...... by PP-pipe heat exchanger. Heat demand is reduced due to direct solar heating, and due to storage. Heat demand is reduced due to direct solar heating, due to storage and due to lower heat losses through the ground. In theory, by running the system flow backwards through the sand storage, active heating...... can be achieved.The objective of the report is to present results from measured system evaluation andcalculations and to give guidelines for the design of such solar heating systems with building integrated sand storage. The report is aimed to non-technicians. In another report R-006 the main results...

Thermophysical properties of dispersed metal materials

Energy Technology Data Exchange (ETDEWEB)

Lee, Sang Hyun; Kim, Jong Chul [KRISS, Taejeon (Korea)

2002-04-01

Thermal conductivities of the preliminarily fabricated U-Mo dispersion fuel meats have been measured to estimate the center temperature of the irradiation fuels. Thermal conductivities at temperatures ranging from room temperature to 500 .deg. C were calculated by measuring diffusivities, specific heat capacities and densities of dispersion fuel meats. The molybdenum content of fuel meats was varied to be 6wt%, 8wt%, and 10wt% and the volume fraction of U-Mo fuel powders were changed to be 10 vol%, 30vol%, 40 vol%, and 50 vol%. 13 refs., 39 figs., 13 tabs. (Author)

Split heat pipe heat recovery system

OpenAIRE

E. Azad

2008-01-01

This paper describes a theoretical analysis of a split heat pipe heat recovery system. The analysis is based on an Effectiveness-NTU approach to deduce its heat transfer characteristics. In this study the variation of overall effectiveness of heat recovery with the number of transfer units are presented. Copyright , Manchester University Press.

Prototype plant for nuclear process heat (PNP), reference phase

International Nuclear Information System (INIS)

Fladerer, R.; Schrader, L.

1982-07-01

The coal gasification processes using nuclear process heat being developed within the framwork of the PNP project, have the advantages of saving feed coal, improving efficiency, reducing emissions, and stabilizing energy costs. One major gasification process is the hydrogasification of coal for producing SNG or gas mixture of carbon monoxide and hydrogen; this process can also be applied in a conventional route. The first steps to develop this process were planning, construction and operation of a semi-technical pilot plant for hydrogasification of coal in a fluidized bed having an input of 100 kg C/h. Before the completion of the development phase (reference phase) describing here, several components were tested on part of which no operational experience had so far been gained; these were the newly developed devices, e.g. the inclined tube for feeding coal into the fluidized bed, and the raw gas/hydrogenation gas heat exchanger for utilizing the waste heat of the raw gas leaving the gasifier. Concept optimizing of the thoroughly tested equipment parts led to an improved operational behaviour. Between 1976 and 1980, the semi-technical pilot plant was operated for about 19,400 hours under test conditions, more than 7,400 hours of which it has worked under gasification conditions. During this time approx. 1,100 metric tons of dry brown coal and more than 13 metric tons of hard coal were gasified. The longest coherent operational phase under gasification conditions was 748 hours in which 85.4 metric tons of dry brown coal were gasified. Carbon gasification rates up to 82% and methane contents in the dry raw gas (free of N 2 ) up to 48 vol.% were obtained. A detailed evaluation of the test results provided information of the results obtained previously. For the completion of the test - primarily of long-term tests - the operation of the semi-technical pilot plant for hydrogasification of coal is to be continued up to September 1982. (orig.) [de

Journal of EAEA, Vol 16, 1999

African Journals Online (AJOL)

Jn this paper, the combined heat and mass transfer of water-vapor into a cylindrical zeolite adsorber has been numerically simulated The two- dimensional heat and mass transfer equations are numerically solved using gPROMS program - a general Process Modeling System [J] program, inserting the proper initial and ...

Heat cascading regenerative sorption heat pump

Science.gov (United States)

Jones, Jack A. (Inventor)

1995-01-01

A simple heat cascading regenerative sorption heat pump process with rejected or waste heat from a higher temperature chemisorption circuit (HTCC) powering a lower temperature physisorption circuit (LTPC) which provides a 30% total improvement over simple regenerative physisorption compression heat pumps when ammonia is both the chemisorbate and physisorbate, and a total improvement of 50% or more for LTPC having two pressure stages. The HTCC contains ammonia and a chemisorbent therefor contained in a plurality of canisters, a condenser-evaporator-radiator system, and a heater, operatively connected together. The LTPC contains ammonia and a physisorbent therefor contained in a plurality of compressors, a condenser-evaporator-radiator system, operatively connected together. A closed heat transfer circuit (CHTC) is provided which contains a flowing heat transfer liquid (FHTL) in thermal communication with each canister and each compressor for cascading heat from the HTCC to the LTPC. Heat is regenerated within the LTPC by transferring heat from one compressor to another. In one embodiment the regeneration is performed by another CHTC containing another FHTL in thermal communication with each compressor. In another embodiment the HTCC powers a lower temperature ammonia water absorption circuit (LTAWAC) which contains a generator-absorber system containing the absorbent, and a condenser-evaporator-radiator system, operatively connected together. The absorbent is water or an absorbent aqueous solution. A CHTC is provided which contains a FHTL in thermal communication with the generator for cascading heat from the HTCC to the LTAWAC. Heat is regenerated within the LTAWAC by transferring heat from the generator to the absorber. The chemical composition of the chemisorbent is different than the chemical composition of the physisorbent, and the absorbent. The chemical composition of the FHTL is different than the chemisorbent, the physisorbent, the absorbent, and ammonia.

Buli. Mater. Sci., Vol. 10, No. 4, July 1988, pp. 367-372. (C

Indian Academy of Sciences (India)

Mater. Sci., Vol. 10, No. 4, July 1988, pp. 367-372. (C) Printed in India. Studies on iron-chromium redox storage system. SH PAWAR, R D MADHALE, P S PATIL and CD LOKHANDE. Department of Physics, Shivaji University, Kolhapur 416 004, India. Abstract. The performance of the redox storage battery based on the Fe-Cr ...

Modeling of heat transfer into a heat pipe for a localized heat input zone

International Nuclear Information System (INIS)

Rosenfeld, J.H.

1987-01-01

A general model is presented for heat transfer into a heat pipe using a localized heat input. Conduction in the wall of the heat pipe and boiling in the interior structure are treated simultaneously. The model is derived from circumferential heat transfer in a cylindrical heat pipe evaporator and for radial heat transfer in a circular disk with boiling from the interior surface. A comparison is made with data for a localized heat input zone. Agreement between the theory and the model is good. This model can be used for design purposes if a boiling correlation is available. The model can be extended to provide improved predictions of heat pipe performance

Industrial excess heat for district heating in Denmark

DEFF Research Database (Denmark)

Bühler, Fabian; Petrovic, Stefan; Karlsson, Kenneth Bernard

2017-01-01

analyses excess heat sources from the industrial sector and how they could be used for district heating. This method first allocates excess heat to single production units by introducing and validating a new approach. Spatial analysis of the heat sources and consumers are then performed to evaluate...... the potential for using them for district heating. In this way the theoretical potential of using the excess heat for covering the heating demand of buildings is determined. Through the use of industry specific temperature profiles the heat usable directly or via heat pumps is further found. A sensitivity...... analysis investigates the impact of future energy efficiency measures in the industry, buildings and the district heating grid on the national potential. The results show that for the case study of Denmark, 1.36 TWh of district heat could be provided annually with industrial excess heat from thermal...

Design of serially connected district heating heat pumps utilising a geothermal heat source

DEFF Research Database (Denmark)

Jensen, Jonas Kjær; Ommen, Torben Schmidt; Markussen, Wiebke Brix

2017-01-01

The design of two heat pumps (HP), connected in series, was investigated for operation in the district heating (DH) network of the Greater Copenhagen area, Denmark. The installation was dimensioned to supply 7.2 MW of heat at a temperature of 85 °C. The heat pumps utilise a geothermal heat source...

Utilising heat from nuclear waste for space heating

International Nuclear Information System (INIS)

Deacon, D.

1982-01-01

A heating unit utilising the decay heat from irradiated material comprises a storage envelope for the material associated with a heat exchange system, means for producing a flow of air over the heat exchange system to extract heat from the material, an exhaust duct capable of discharging the heated air to the atmosphere, and means for selectively diverting at least some of the heated air to effect the required heating. With the flow of air over the heat exchange system taking place by a natural thermosyphon process the arrangement is self regulating and inherently reliable. (author)

Heat pumps in district heating networks

DEFF Research Database (Denmark)

Ommen, Torben Schmidt; Markussen, Wiebke Brix; Elmegaard, Brian

constraints limit the power plants. Efficient heat pumps can be used to decouple the constraints of electricity and heat production, while maintaining the high energy efficiency needed to match the politically agreed carbon emission goals. The requirements in terms of COP, location, capacity and economy...... and strategic planning in the energy sector. The paper presents a case study of optimal implementation of heat pumps in the present energy system of the Copenhagen area. By introduction of the correct capacity of heat pumps, a 1,6 % reduction in fuel consumption for electricity and heat production can...

Experimental device for the residential heating with heat pipe and electric heat storage blocks

Energy Technology Data Exchange (ETDEWEB)

Vasiliev, L L; Boldak, I M; Domorod, L S; Rabetsky, M I; Schirokov, E I [AN Belorusskoj SSR, Minsk (Belarus). Inst. Teplo- i Massoobmena

1992-01-01

Residential heating using electric heat storage blocks nowadays is an actual problem from the point of view of heat recovery and nature protection. In the Luikov Heat and Mass Transfer Institute a new residential electrical heater capable of heating chambers by controlling air temperature and heat output using heat pipes and an electric heat storage block was developed. This heater (BETA) is fed from the source of energy and during 7 h of night time accumulates energy sufficiently to heat 10 m{sup 3} during 24 h. Heating device BETA has a ceramic thermal storage block, electric heaters and a heat pipe with evaporator inside the ceramic block and constant temperature (65{sup o}C) finned condenser outside it. The condenser temperature could be controlled easily. BETA is compact, has high thermal response, accurate air temperature control and safe operation. Such types of residential heaters are necessary for heating residential and office building in the Mogilev and Gomel regions in Byelorussia which suffered after the Chernobyl catastrophe. (Author).

Study of selective heating at ion cyclotron resonance for the plasma separation process

Science.gov (United States)

Compant La Fontaine, A.; Pashkovsky, V. G.

1995-12-01

The plasma separation process by ion cyclotron resonance heating (ICRH) is studied both theoretically and experimentally on two devices: the first one called ERIC (Ion Cyclotron Resonance Experiment) at Saclay (France) [P. Louvet, Proceedings of the 2nd Workshop on Separation Phenomena in Liquids and Gases, Versailles, France, 1989, edited by P. Louvet, P. Noe, and Soubbaramayer (Centre d'Etudes Nucléaires de Saclay and Cité Scientifique Parcs et Technopoles, Ile de France Sud, France, 1989), Vol. 1, p. 5] and the other one named SIRENA at the Kurchatov Institute, Moscow, Russia [A. I. Karchevskii et al., Plasma Phys. Rep. 19, 214 (1993)]. The radio frequency (RF) transversal magnetic field is measured by a magnetic probe both in plasma and vacuum and its Fourier spectrum versus the axial wave number kz is obtained. These results are in agreement with the electromagnetic (EM) field calculation model based on resolution of Maxwell equations by a time-harmonic scheme studied here. Various axial boundary conditions models used to compute the EM field are considered. The RF magnetic field is weakly influenced by the plasma while the electric field components are strongly disturbed due to space-charge effects. In the plasma the transversal electric field is enhanced and the kz spectrum is narrower than in vacuum. The calculation of the resonant isotope heating is made by the Runge-Kutta method. The influence of ion-ion collisions, inhomogeneity of the static magnetic field B0, and the RF transversal magnetic field component on the ion acceleration is examined. These results are successfully compared with experiments of a minor isotope 44Ca heating measurements, made with an energy analyzer.

Image quality and volume computed tomography air kerma index (C{sub vol}) evaluation in Recife; Avaliacao da qualidade de imagem e do indice volumetrico de Kerma ar em tomografia computadorizada (C{sub vol}) em Recife

Energy Technology Data Exchange (ETDEWEB)

Andrade, Marcos Ely Almeida

2008-07-01

The Computed Tomography (CT) is an important diagnostic imaging method, widely used. However, in spite of all the advantages and technologic advances within the CT scanners, the tomographic procedures result in high absorbed doses to patients. The main objective of this work was to perform a dosimetric study of CT scanners located at Recife and to evaluate the image quality on CT examinations in these equipment. The volume CT air kerma index (C{sub VOL}) and air kerma length product (P{sub KL,CT}) were estimated. These values were calculated using normalized weighted air kerma indexes in CT standard dosimetry phantoms ({sub n}C{sub W}), supplied by ImPACT group for several CT scanners, and the scan parameters of routine head, routine chest and hi-resolution chest CT exams performed at 20 institutions. The irradiation parameters of 15 adult patients for each CT procedure were registered at six participating centres, at which the phantom from the American College of Radiology (ACR) CT accreditation protocol was used for the image quality measurements. For routine head exams, the C{sub VOL} values varied between 12 and 58 mGy (at the posterior fossa) and 15 to 58 mGy (at the cerebrum) and the P{sub KL,CT}, from 150 to 750 mGy{center_dot}cm. The C{sub VOL} values for routine chest procedures varied from 3 to 26 mGy and the P{sub KL,CT}, between 120 and 460 mGy{center_dot}cm. In relation to Hi-resolution chest exams, C{sub VOL} values were from 1.0 to 2.7 mGy and the P{sub KL,CT} values varied between 24 and 67 mGy{center_dot}cm. The image quality evaluations results showed that almost all scanners presented at least one inadequacy. One of the equipment presented faults at 70% of the tests. With regard to the image noise, only two scanners presented acceptable results. From these results, it is possible to conclude that the volume CT air kerma index values are lower than the European reference levels. However, the image quality of these CT scanners does not attend the

Solar heat storages in district heating networks

Energy Technology Data Exchange (ETDEWEB)

Ellehauge, K. (Ellehauge og Kildemoes, AArhus (DK)); Engberg Pedersen, T. (COWI A/S, Kgs. Lyngby (DK))

2007-07-15

This report gives information on the work carried out and the results obtained in Denmark on storages for large solar heating plants in district heating networks. Especially in Denmark the share of district heating has increased to a large percentage. In 1981 around 33% of all dwellings in DK were connected to a district heating network, while the percentage in 2006 was about 60% (in total 1.5 mio. dwellings). In the report storage types for short term storage and long term storages are described. Short term storages are done as steel tanks and is well established technology widely used in district heating networks. Long term storages are experimental and used in connection with solar heating. A number of solar heating plants have been established with either short term or long term storages showing economy competitive with normal energy sources. Since, in the majority of the Danish district heating networks the heat is produced in co-generation plants, i.e. plants producing both electricity and heat for the network, special attention has been put on the use of solar energy in combination with co-generation. Part of this report describes that in the liberalized electricity market central solar heating plants can also be advantageous in combination with co-generation plants. (au)

Fast Reactor Physics. Vol. II. Proceedings of a Symposium on Fast Reactor Physics and Related Safety Problems

International Nuclear Information System (INIS)

1968-01-01

Proceedings of a Symposium organized by the IAEA and held in Karlsruhe, 30 October - 3 November 1967. The meeting was attended by 183 scientists from 23 countries and three international organizations. Contents: (Vol.1) Review of national programmes (5 papers); Nuclear data for fast reactors (12 papers); Experimental methods (3 papers); Zoned systems (7 papers); Kinetics (7 papers). (Vol.11) Fast critical experiments (8 papers); Heterogeneity in fast critical experiments (5 papers); Fast power reactors (13 papers); Fast pulsed reactors (3 papers); Panel discussion. Each paper is in its original language (50 English, 11 French and 3 Russian) and is preceded by an abstract in English with a second one in the original language if this is not English. Discussions are in English. (author)

24 CFR 3280.506 - Heat loss/heat gain.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Heat loss/heat gain. 3280.506... URBAN DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.506 Heat loss/heat gain. The manufactured home heat loss/heat gain shall be determined by methods outlined in...

Automation of heating system with heat pump

OpenAIRE

Ferdin, Gašper

2016-01-01

Because of high prices of energy, we are upgrading our heating systems with newer, more fuel efficient heating devices. Each new device has its own control system, which operates independently from other devices in a heating system. With a relatively low investment costs in automation, we can group devices in one central control system and increase the energy efficiency of a heating system. In this project, we show how to connect an oil furnace, a sanitary heat pump, solar panels and a heat p...

Regenerative heat sources for heating networks

International Nuclear Information System (INIS)

Huenges, Ernst; Sperber, Evelyn; Eggers, Jan-Bleicke; Noll, Florian; Kallert, Anna Maria; Reuss, Manfred

2015-01-01

The ambitious goal, the German Federal Government has set itself, to reduce the emissions of greenhouse gases by 80% to 95% by the year 2050. As there are currently more than half of German energy consumption for the production of heat is required, big contributions to climate protection can be expected from this area if more renewable heat sources are used. Renewable heat sources such as bioenergy, solar thermal and geothermal energy in particular can be provided as compared to fossil fuels with significantly lower specific CO 2 emissions. Objectives in the heating market and scenarios for the transformation of the heat sector have been elaborated in the BMU Lead Study 2011. The main pillar of this scenario is the reduction of final energy consumption for heat by the energy-efficient renovation of existing buildings and further increasing demands on the energetic quality of new buildings. To cover the remaining energy demand, a focus is on the expansion of heating networks based on renewable energies. [de

Effects of Heat of Vaporization and Octane Sensitivity on Knock-Limited Spark Ignition Engine Performance

Energy Technology Data Exchange (ETDEWEB)

Ratcliff, Matthew A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Burton, Jonathan L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Sindler, Petr [National Renewable Energy Laboratory (NREL), Golden, CO (United States); McCormick, Robert L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Christensen, Earl D [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Fouts, Lisa A [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2018-04-03

Knock-limited loads for a set of surrogate gasolines all having nominal 100 research octane number (RON), approximately 11 octane sensitivity (S), and a heat of vaporization (HOV) range of 390 to 595 kJ/kg at 25 degrees C were investigated. A single-cylinder spark-ignition engine derived from a General Motors Ecotec direct injection (DI) engine was used to perform load sweeps at a fixed intake air temperature (IAT) of 50 degrees C, as well as knock-limited load measurements across a range of IATs up to 90 degrees C. Both DI and pre-vaporized fuel (supplied by a fuel injector mounted far upstream of the intake valves and heated intake runner walls) experiments were performed to separate the chemical and thermal effects of the fuels' knock resistance. The DI load sweeps at 50 degrees C intake air temperature showed no effect of HOV on the knock-limited performance. The data suggest that HOV acts as a thermal contributor to S under the conditions studied. Measurement of knock-limited loads from the IAT sweeps for DI at late combustion phasing showed that a 40 vol% ethanol (E40) blend provided additional knock resistance at the highest temperatures, compared to a 20 vol% ethanol blend and hydrocarbon fuel with similar RON and S. Using the pre-vaporized fuel system, all the high S fuels produced nearly identical knock-limited loads at each temperature across the range of IATs studied. For these fuels RON ranged from 99.2 to 101.1 and S ranged from 9.4 to 12.2, with E40 having the lowest RON and highest S. The higher knock-limited loads for E40 at the highest IATs examined were consistent with the slightly higher S for this fuel, and the lower engine operating condition K values arising from use of this fuel. The study highlights how fuel HOV can affect the temperature at intake valve closing, and consequently the pressure-temperature history of the end gas leading to more negative values of K, thereby enhancing the effect of S on knock resistance.

RECEPTOR SUPERFAMILY OF TUMOR NECROSIS FACTOR Α, AND HSP90 HEAT SHOCK PROTEIN: A MOLECULAR BASIS FOR INTERACTIONS

Directory of Open Access Journals (Sweden)

N. V. Ryazantseva

2011-01-01

Full Text Available Abstract.  A  study  was  performed  aiming  to  investigate  interactions  between  TNFα  receptor  (TNF1 superfamily and heat shock protein Hsp90, using a Jurkat tumor cell line. The tumor cells cultured in presence of Hsp90 inhibitor (17-AAG showed increased numbers of cells, presenting surface TNFR1 and FasR, which facilitate  triggering  of  programmed  cell  death.  It  was  also  revealed  that  Hsp90  blockage  under  the  in  vitro conditions causes a decrease in FasL, while not affecting TNFα and sTNFR1 production by the tumor cells. (Med. Immunol., 2011, vol. 13, N 2-3, pp 247-252 

Heat pipes for ground heating and cooling

Energy Technology Data Exchange (ETDEWEB)

Vasiliev, L L

1988-01-01

Different versions of heat pipe ground heating and cooling devices are considered. Solar energy, biomass, ground stored energy, recovered heat of industrial enterprises and ambient cold air are used as energy and cold sources. Heat pipe utilization of air in winter makes it possible to design accumulators of cold and ensures deep freezing of ground in order to increase its mechanical strength when building roadways through the swamps and ponds in Siberia. Long-term underground heat storage systems are considered, in which the solar and biomass energy is accumulated and then transferred to heat dwellings and greenhouses, as well as to remove snow from roadways with the help of heat pipes and solar collectors.

Effect of heated length on the Critical Heat Flux of subcooled flow boiling. 2. Effective heated length under axially nonuniform heating condition

International Nuclear Information System (INIS)

Kinoshita, Hidetaka; Yoshida, Takuya; Nariai, Hideki; Inasaka, Fujio

1998-01-01

Effect of heated length on the Critical Heat Flux (CHF) of subcooled flow boiling with water was experimentally investigated by using direct current heated tube made of stainless steel a part of whose wall thickness was axially cut for realizing nonuniform heat flux condition. The higher enhancement of the CHF was derived for shorter tube length. The effective heated length was determined for the tube under axially nonuniform heat flux condition. When the lower heat flux part below the Net Vapor Generation (NVG) heat flux exists at the middle of tube length, then the effective heated length becomes the tube length downstream the lower heat flux parts. However, when the lower heat flux part is above the NVG, then the effective heated length is full tube length. (author)

Heat Roadmap Europe: Identifying strategic heat synergy regions

International Nuclear Information System (INIS)

Persson, U.; Möller, B.; Werner, S.

2014-01-01

This study presents a methodology to assess annual excess heat volumes from fuel combustion activities in energy and industry sector facilities based on carbon dioxide emission data. The aim is to determine regional balances of excess heat relative heat demands for all third level administrative regions in the European Union (EU) and to identify strategic regions suitable for large-scale implementation of district heating. The approach is motivated since the efficiency of current supply structures to meet building heat demands, mainly characterised by direct use of primary energy sources, is low and improvable. District heating is conceived as an urban supply side energy efficiency measure employable to enhance energy system efficiency by increased excess heat recoveries; hereby reducing primary energy demands by fuel substitution. However, the importance of heat has long been underestimated in EU decarbonisation strategies and local heat synergies have often been overlooked in energy models used for such scenarios. Study results indicate that 46% of all excess heat in EU27, corresponding to 31% of total building heat demands, is located within identified strategic regions. Still, a realisation of these rich opportunities will require higher recognition of the heat sector in future EU energy policy. - Highlights: • EU27 energy and industry sector heat recycling resources are mapped and quantified. • Target regions for large-scale implementation of district heating are identified. • 46% of total EU27 excess heat volume is seized in 63 strategic heat synergy regions. • Large urban zones have lead roles to play in transition to sustainability in Europe. • Higher recognition of heat sector is needed in future EU energy policy for realisation

A background to risk analysis. Vol. 3

International Nuclear Information System (INIS)

Taylor, J.R.

1979-01-01

This 4-volumes report gives a background of ideas, principles, and examples which might be of use in developing practical methods for risk analysis. Some of the risk analysis techniques described are somewhat experimental. The report is written in an introductory style, but where some point needs further justifi- cation or evaluation, this is given in the form of a chapter appenix. In this way, it is hoped that the report can serve two purposes, - as a basis for starting risk analysis work and as a basis for discussing effectiveness of risk analysis procedures. The report should be seen as a preliminary stage, prior to a program of industrial trials of risk analysis methods. Vol. 3 contains chapters on quantification of risk, failure and accident probability, risk analysis and design, and examles of risk analysis for process plant. (BP)

Heat transfer and critical heat flux in a spiral flow in an asymmetrical heated tube

International Nuclear Information System (INIS)

Boscary, J.; Association Euratom-CEA, Centre d'Etudes Nucleaires de Cadarache, 13 - Saint-Paul-lez-Durance

1997-03-01

The design of plasma facing components is crucial for plasma performance in next fusion reactors. These elements will be submitted to very high heat flux. They will be actively water-cooled by swirl tubes in the subcooled boiling regime. High heat flux experiments were conducted in order to analyse the heat transfer and to evaluate the critical heat flux. Water-cooled mock-ups were one-side heated by an electron beam gun for different thermal-hydraulic conditions. The critical heat flux was detected by an original method based on the isotherm modification on the heated surface. The wall heat transfer law including forced convection and subcooled boiling regimes was established. Numerical calculations of the material heat transfer conduction allowed the non-homogeneous distribution of the wall temperature and of the wall heat flux to be evaluated. The critical heat flux value was defined as the wall maximum heat flux. A critical heat flux model based on the liquid sublayer dryout under a vapor blanket was established. A good agreement with test results was found. (author)

Author Details

African Journals Online (AJOL)

Lasode, OA. Vol 3, No 2 (2003) - Articles Inventory of alloy composition, microstructures and mechanical properties of automobile engine parts. Abstract · Vol 4, No 2 (2004) - Articles An improved solar cabinet dryer with natural convective heat transfer. Abstract. ISSN: 1596-3233. AJOL African Journals Online. HOW TO USE ...

Author Details

African Journals Online (AJOL)

Tella, B A. Vol 51, No 6 (2007) - Articles Comparison of the Effect of Neuromuscular Electrical Stimulation and Cryotherapy on Spasticity and Hand Function in Patients with Spastic Cerebral Palsy Abstract · Vol 51, No 5 (2007) - Articles Continuous low-level tropical heat compared with transcutaneous electic nerve ...

Análise qualitativa de compostos voláteis do headspace de carne cozida de ovinos e caprinos

Directory of Open Access Journals (Sweden)

Jossiê Zamperetti Donadel

2013-11-01

Full Text Available Este estudo teve como objetivo caracterizar qualitativamente os compostos voláteis (CV do headspace de diferentes músculos de carne cozida de ovinos e caprinos da região do Alto Camaquã, Rio Grande do Sul - Brasil. Os CV do headspace dos músculos cozidos, L. dorsi e V. lateralis de cinco ovinos machos (idade de 6 meses e cinco cabritos machos castrados (idade de 8-9 meses foram analisados pela técnica de microextração em fase sólida (HS-SPME e cromatógrafo a gás acoplado a espectrômetro de massas (GC/MS. Foram encontrados 73 compostos voláteis, dentre eles aldeídos, cetonas e compostos sulfurados, característicos de carne processada termicamente. A partir da fração volátil, foi possível encontrar marcadores que discriminassem as espécies animais estudadas, caracterizando os caprinos por apresentarem, entre outros compostos, terpenos (β-pineno, α-gurjuneno, α-muuroleno, ausentes em ovinos. Alguns compostos discriminaram V. lateralis e L. dorsi de ovinos, como álcool isopropílico, α-pineno, o-xileno, porém não foi possível obter uma diferenciação entre os músculos de caprinos.

Volátiles generados por hidrólisis enzimática de glicósidos de hojas de lulo (Solanum quitoense L.

Directory of Open Access Journals (Sweden)

Carolina Osorio R.

2010-07-01

Full Text Available La fracción glicosídica de hojas de lulo (Solanum quitoense L. fue obtenida por adsorción sobre Amberlita XAD-2 y posterior elución con metanol. Los glicósidos así extraídos se hidrolizaron enzimáticamente con una glicosidasa no selectiva (Rohapect D5-L y las agliconas (volátiles enlazados glicosídicamente producidas fueron caracterizadas químicamente por CGAR (cromatografía de gases de alta resolución, CGAR-EM (cromatografía de gases de alta resolución acoplada a espectrometría de masas y analizadas sensorialmente (nota olfativa por CGAR-O (cromatografía de gases de alta resolución acoplada a olfatometría. Se detectaron en total 25 compuestos volátiles y de ellos, se identificaron 21, los cuales representan el 90 % de todas las agliconas generadas. Los volátiles identificados presentaron diversas estructuras químicas que pueden agruparse en Ci3-norisoprenoides (38.1 %, 15 mg/kg hojas, compuestos aromáticos (30.5 %, alcoholes monoterpénicos (12.3 % y compuestos alifáticos Cg (9.3 %. El extracto de volátiles producido por hidrólisis enzimática presentó un olor a verde amaderado agradable, con fuertes notas dulces parecidas a la miel.

Urban district heating using nuclear heat - a survey

International Nuclear Information System (INIS)

Beresovski, T.; Oliker, I.

1979-01-01

The use of heat from nuclear power plants is of great interest in connection with projected future expansions of large urban district heating systems. Oil price escalation and air pollution from increased burning of fossil fuels are substantial incentivers for the adoption of nuclear heat and power plants. The cost of the hot water piping system from the nuclear plant to the city is a major factor in determining the feasibility of using nuclear heat. To achieve reasonable costs, the heat load should be at least 1500 MW(th), transport temperatures 125-200 0 C and distances preferably 50 km or less. Heat may be extracted from the turbines of conventional power reactors. Alternatively, some special-purpose smaller reactors are under development which are specially suited to production of heat with little or no power coproduct. Many countries are conducting studies of future expansions of district heating systems to use nuclear heat. Several countries are developing technology suitable for this application. Actual experience with the use of nuclear heat for district heating is currently being gained only in the USSR, however. While district heating appears to be a desirable technology at a time of increasing fossil-fuel costs, the use of nuclear heat will require siting of nuclear plants within transmission radius of cities. The institutional barries toward use of nuclear heating will have to be overcome before the energy conservation potential of this approach can be realized on a significant scale. (author)

Reactor waste heat utilization and district heating reactors. Nuclear district heating in Sweden - Regional reject heat utilization schemes and small heat-only reactors

International Nuclear Information System (INIS)

Hannerz, K.; Larsson, Y.; Margen, P.

1977-01-01

A brief review is given of the current status of district heating in Sweden. In future, district heating schemes will become increasingly interesting as a means of utilizing heat from nuclear reactors. Present recommendations in Sweden are that large reactors should not be located closer than about 20 km from large population centres. Reject heat from such reactors is cheap at source. To minimize the cost of long distance hot water transmission large heat rates must be transmitted. Only areas with large populations can meet this requirement. The three areas of main interest are Malmoe/Lund/Helsingborg housing close to 0.5 million; Greater Stockholm housing 1 to 1.5 million and Greater Gothenburg housing about 0.5 million people. There is an active proposal that the Malmoe/Lund/Helsingborg region would be served by a third nuclear unit at Barsebaeck, located about 20 km from Malmoe/Lund and supplying 950 MW of base load heat. Preliminary proposals for Stockholm involve a 2000 MW heat supply; proposals for Gothenburg are more tentative. The paper describes progress on these proposals and their technology. It also outlines technology under development to increase the economic range of large scale heat transport and to make distribution economic even for low heat-density family housing estates. Regions apart from the few major urban areas mentioned above require the adoption of a different approach. To this end the development of a small, simple low-temperature reactor for heat-only production suitable for urban location has been started in Sweden in close contact with Finland. Some results of the work in progress are presented, with emphasis on the safety requirements. An outline is given in the paper as to how problems of regional heat planning and institutional and legislative issues are being approached

Heat pipes as perspective base elements of heat recovery in heat supply and ventilating systems

Directory of Open Access Journals (Sweden)

Matveev Andrey

2017-01-01

Full Text Available Thermotechnical characteristics of heat pipes are considered as high-efficient heat-transfer devices, which can provide energy-saving technologies for heat supply and ventilating systems and for different branches of industry. Thermotechnical and working (”performance capability” characteristics of heat pipes are investigated. By ”performance capability” of heat pipes and heat-transfer devices on heat pipes we mean the system state, where it can perform set functions and keep parameter values (thermal power, conductivity, thermal resistance, heat-transfer coefficient, temperature level and differential, etc. within the regulations of standardized specifications. The article presents theoretical and experimental methods of «gaslock» length determination on noncondensable gases during long-lasting tests of ammonia heat pipes made of aluminum shape АS – КRА 7.5 – R1 (alloy АD – 31. The paper gives results of research of thermotechnical characteristics of heat pipes in horizontal and vertical states (separate and as a set part while using different systems of thermal insulation. The obtained results of thermotechnical and resource tests show the advantages of ammonia heat pipes as basic elements for heat exchanger design in heating and ventilation systems.

Influence on Heat Transfer Coefficient of Heat Exchanger by Velocity and Heat Transfer Temperature Difference

Directory of Open Access Journals (Sweden)

WANG Fang

2017-04-01

Full Text Available Aimed to insufficient heat transfer of heat exchanger, research the influence on the heat transfer coefficient impacted by velocity and heat transfer temperature difference of tube heat exchanger. According to the different heat transfer temperature difference and gas velocity，the experimental data were divided into group. Using the control variable method，the above two factors were analyzed separately. K一△T and k一:fitting curve were clone to obtain empirical function. The entire heat exchanger is as the study object，using numerical simulation methods，porous media，k一￡model，second order upwind mode，and pressure一velocity coupling with SIMPLE algorithm，the entire heat exchanger temperature field and the heat transfer coefficient distribution were given. Finally the trend of the heat transfer coefficient effected by the above two factors was gotten.

Heat-treatment and heat-to-heat variations in the fracture toughness of Alloy 718

International Nuclear Information System (INIS)

Mills, W.J.

1981-07-01

The effect of heat-treatment and heat-to-heat variations on the J Ic fracture toughness response of Alloy 718 was examined at room and elevated temperatures using the multiple-specimen R-curve technique. Six heats of alloy 718 were tested in the conventional and modified heat-treated conditions. The fracture toughness response for the modified superalloy was found to be superior to that exhibited by the conventional material. Heat-to-heat variations in the J Ic response of Alloy 718 were observed in both heat-treated conditions; the modified treatment exhibited much larger variability. The J Ic and corresponding K Ic fracture toughness values were analyzed statistically to establish minimum expected toughness, values for use in design and safety analyses. 26 refs., 10 figs., 9 tabs

View factor for radiation heat exchange between the wall and end of a cylinder

International Nuclear Information System (INIS)

Al-Bahadili, H.; Wood, J.

1991-01-01

In a paper by previous authors (Carlson and Garcia (1984) Ann. Nucl. Energy Vol 11, No 4), a numerical integration technique (trapezoidal rule) is developed for the approximate calculation of view factors for radiant heat transfer, for both internal and external radiation, from the curved surface of a right circular cylinder. In that paper the variation of view factor for internal radiation (wall to bottom of cylinder) with height, H, of the cylinder, is shown to reach a maximum value of about 0.36 when H is about 0.3. This behaviour is remarked upon in the text. We wish to make two points: (i) the internal view factors for the cylinder can be determined analytically (ii) the view factor behavior shown is erroneous. In fact, the view factor decreases monatonically as H increases, achieving its greatest value (0.5) as H tends to zero. H is normalised to a radius of unity. (author)

Thermal Analysis of Copper-Titanium-Multiwall Carbon Nanotube Composites.

Science.gov (United States)

Hamamda, Smail; Jari, Ahmed; Revo, S; Ivanenko, K; Jari, Youcef; Avramenko, T

2017-12-01

The aim of this research is the thermostructural study of Cu-Ti, Cu-Ti 1 vol% multiwall carbon nanotubes (MWCNTs) and Cu-Ti 3 vol% MWCNTs. Several investigation techniques were used to achieve this objective. Dilatometric data show that the coefficient of thermal expansion of the nanocomposite containing less multiwall carbon nanotubes is linear and small. The same nanocomposite exhibits regular heat transfer and weak mass exchange with the environment. Raman spectroscopy shows that the nanocomposite with more MWCNTs contains more defects. This implies that the carbon nanotubes have better dispersion in Cu-Ti 1 vol% MWCNTs. Infrared spectroscopy reveals that Cu-Ti 1 vol% MWCNTs has better crystallinity than Cu-Ti 3 vol% MWCNTs.

Residential CO{sub 2} heat pump system for combined space heating and hot water heating

Energy Technology Data Exchange (ETDEWEB)

Stene, Joern

2004-02-01

Carbon dioxide (CO{sub 2}, R-744) has been identified as a promising alternative to conventional working fluids in a number of applications due to its favourable environmental and thermophysical properties. Previous work on residential CO{sub 2} heat pumps has been dealing with systems for either space heating or hot water heating, and it was therefore considered interesting to carry out a theoretical and experimental study of residential CO{sub 2} heat pump systems for combined space heating and hot water heating - o-called integrated CO{sub 2} heat pump systems. The scope of this thesis is limited to brine-to-water and water-to-water heat pumps connected to low-temperature hydronic space heating systems. The main conclusions are: (1) Under certain conditions residential CO{sub 2} heat pump systems for combined space heating and hot water heating may achieve the same or higher seasonal performance factor (SPF) than the most energy efficient state-of-the-art brine-to-water heat pumps. (2) In contrary to conventional heat pump systems for combined space heating and DHW heating, the integrated CO{sub 2} heat pump system achieves the highest COP in the combined heating mode and the DHW heating mode, and the lowest COP in the space heating mode. Hence, the larger the annual DHW heating demand, the higher the SPF of the integrated CO{sub 2} heat pump system. (3) The lower the return temperature in the space heating system and the lower the DHW storage temperature, the higher the COP of the integrated CO{sub 2} heat pump. A low return temperature in the space heating system also results in a moderate DHW heating capacity ratio, which means that a relatively large part of the annual space heating demand can be covered by operation in the combined heating mode, where the COP is considerably higher than in the space heating mode. (4) During operation in the combined heating mode and the DHW heating mode, the COP of the integrated CO{sub 2} heat pump is heavily influenced by

Waste heat of HTR power stations for district heating

International Nuclear Information System (INIS)

Bonnenberg, H.; Schlenker, H.V.

1975-01-01

The market situation, the applied techniques, and the transport, for district heating in combination with HTR plants are considered. Analysis of the heat market indicates a high demand for heat at temperatures between 100 and 150 0 C in household and industry. This market for district heating can be supplied by heat generated in HTR plants using two methods: (1) the combined heat and power generation in steam cycle plants by extracting steam from the turbine, and (2) the use of waste heat of a closed gas turbine cycle. The heat generation costs of (2) are negligible. The cost for transportation of heat over the average distance between existing plant sites and consumer regions (25 km) are between 10 and 20% of the total heat price, considering the high heat output of nuclear power stations. Comparing the price of heat gained by use of waste heat in HTR plants with that of conventional methods, considerable advantages are indicated for the combined heat and power generation in HTR plants. (author)

Buffer AVL Alone Does Not Inactivate Ebola Virus in a Representative Clinical Sample Type.

Science.gov (United States)

Smither, Sophie J; Weller, Simon A; Phelps, Amanda; Eastaugh, Lin; Ngugi, Sarah; O'Brien, Lyn M; Steward, Jackie; Lonsdale, Steve G; Lever, Mark S

2015-10-01

Rapid inactivation of Ebola virus (EBOV) is crucial for high-throughput testing of clinical samples in low-resource, outbreak scenarios. The EBOV inactivation efficacy of Buffer AVL (Qiagen) was tested against marmoset serum (EBOV concentration of 1 × 10(8) 50% tissue culture infective dose per milliliter [TCID50 · ml(-1)]) and murine blood (EBOV concentration of 1 × 10(7) TCID50 · ml(-1)) at 4:1 vol/vol buffer/sample ratios. Posttreatment cell culture and enzyme-linked immunosorbent assay (ELISA) analysis indicated that treatment with Buffer AVL did not inactivate EBOV in 67% of samples, indicating that Buffer AVL, which is designed for RNA extraction and not virus inactivation, cannot be guaranteed to inactivate EBOV in diagnostic samples. Murine blood samples treated with ethanol (4:1 [vol/vol] ethanol/sample) or heat (60°C for 15 min) also showed no viral inactivation in 67% or 100% of samples, respectively. However, combined Buffer AVL and ethanol or Buffer AVL and heat treatments showed total viral inactivation in 100% of samples tested. The Buffer AVL plus ethanol and Buffer AVL plus heat treatments were also shown not to affect the extraction of PCR quality RNA from EBOV-spiked murine blood samples. © Crown copyright 2015.

Jet Joint Undertaking. Vol. 2

International Nuclear Information System (INIS)

1989-06-01

The scientific, technical, experimental and theoretical investigations related to JET tokamak are presented. The JET Joint Undertaking, Volume 2, includes papers presented at: the 15th European Conference on controlled fusion and plasma heating, the 15th Symposium on fusion technology, the 12th IAEA Conference on plasma physics and controlled nuclear fusion research, the 8th Topical Meeting on technology of fusion. Moreover, the following topics, concerning JET, are discussed: experience with wall materials, plasma performance, high power ion cyclotron resonance heating, plasma boundary, results and prospects for fusion, preparation for D-T operation, active gas handling system and remote handling equipment

Postaccident heat removal. II. Heat transfer from an internally heated liquid to a melting solid

International Nuclear Information System (INIS)

Faw, R.E.; Baker, L. Jr.

1976-01-01

Microwave heating has been used in studies of heat transfer from a horizontal layer of internally heated liquid to a melting solid. Experiments were designed to simulate heat transfer and meltthrough processes of importance in the analysis of postaccident heat removal capabilities of nuclear reactors. Glycerin, heated by 2.45-GHz microwave radiation, was used to simulate molten fuel. Paraffin wax was used to simulate a melting barrier confining the fuel. Experimentally measured heat fluxes and melting rates were consistent with a model based on downward heat transfer by conduction through a stagnant liquid layer and upward heat transfer augmented by natural convection. Melting and displacement of the barrier material occurred by upward-moving droplets randomly distributed across the melting surface. Results indicated that the melting and displacement process had no effect on the heat transfer process

Effects of Symmetrically Arranged Heat Sources on the Heat Release Performance of Extruded-Type Heat Sinks

Energy Technology Data Exchange (ETDEWEB)

Ku, Min Ye [Chonbuk National Univ., Chonju (Korea, Republic of)

2016-02-15

In this study we investigated the effects of symmetrically arranged heat sources on the heat release performances of extruded-type heat sinks through experiments and thermal fluid simulations. Also, based on the results we suggested a high-efficiency and cost-effective heat sink for a solar inverter cooling system. In this parametric study, the temperatures between heaters on the base plate and the heat release rates were investigated with respect to the arrangements of heat sources and amounts of heat input. Based on the results we believe that the use of both sides of the heat sink is the preferred method for releasing the heat from the heat source to the ambient environment rather than the use of a single side of the heat sink. Also from the results, it is believed that the symmetric arrangement of the heat sources is recommended to achieve a higher rate of heat transfer. From the results of the thermal fluid simulation, it was possible to confirm the qualitative agreement with the experimental results. Finally, quantitative comparison with respect to mass flow rates, heat inputs, and arrangements of the heat source was also performed.

Author Details

African Journals Online (AJOL)

Olayinka, DN. Vol 7, No 1 (2012) - Articles Determination of Land Surface Temperature (LST) and Potential Urban Heat Island Effect in Parts of Lagos State using Satellite Imageries Abstract · Vol 7, No 1 (2012) - Articles Transformation of Shuttle Radar Topography Mission (SRTM) Digital Elevation Data to Nigerian Height ...

Author Details

African Journals Online (AJOL)

Israel-Cookey, C. Vol 11, No 3 (2007) - Articles The Effects of Radiation on the Linear Stability of a horizontal layer in a Fluidsaturated Media heated from below. Abstract PDF · Vol 13, No 3 (2009) - Articles Mathematical Modelling of Tsunami Propagation Abstract PDF. ISSN: 1119-8362. AJOL African Journals Online.

Heat exchangers

Energy Technology Data Exchange (ETDEWEB)

Schmidt, E L; Eisenmann, G; Hahne, E [Stuttgart Univ. (TH) (F.R. Germany). Inst. fuer Thermodynamik und Waermetechnik

1976-04-01

A survey is presented on publications on design, heat transfer, form factors, free convection, evaporation processes, cooling towers, condensation, annular gap, cross-flowed cylinders, axial flow through a bundle of tubes, roughnesses, convective heat transfer, loss of pressure, radiative heat transfer, finned surfaces, spiral heat exchangers, curved pipes, regeneraters, heat pipes, heat carriers, scaling, heat recovery systems, materials selection, strength calculation, control, instabilities, automation of circuits, operational problems and optimization.

Radiation effects on heat transfer in heat exchangers, (2)

International Nuclear Information System (INIS)

Mori, Yasuo; Watanabe, Kenji; Taira, Tatsuji.

1980-01-01

In a high temperature gas-cooled reactor system, in which the working fluid exchanges heat at high temperature near 1000 deg C, the heat transfer acceleration by positively utilizing the radiation heat transfer between solid surfaces should be considered. This paper reports on the results of experiment and analysis for the effects of radiant heat on the heat transfer performance at elevated temperature by applying the heat transfer-accelerating method using radiators to the heat exchanger with tube bundle composed of two channels of heating and heated sides. As the test heat exchangers, a parallel counter flow exchanger and the cross flow exchanger simulating helical tubes were employed, and the results studied on the characteristics of each heat exchanger are described. The plates placed in parallel to flow in every space of the tube bundle arranged in a matrix were used as the heat transfer accelerator. The effects of acceleration with the plates were the increase of heat transmission from 12 to 24% and 12 to 38% in the parallel flow and cross flow heat exchangers, respectively. Also, it was clarified that the theoretical analysis, in which it was assumed that the region within pitch S and two radiator plates, with a heat-transferring tube placed at the center, is the minimum domain for calculation, and that the heat exchange by radiation occurs only between the domain and the adjacent domains, can estimate the heat transfer-accelerating effect and the temperature distribution in a heat exchanger with sufficient accuracy. (Wakatsuki, Y.)

Heat transfer from two-side heated helical channels

International Nuclear Information System (INIS)

Shimonis, V.; Ragaishis, V.; Poshkas, P.

1995-01-01

Experimental results are presented on the heat transfer from two-side heated helical channels to gas (air) flows. The study covered six configurations and wide ranges of geometrical (D/h=5.5 to 84.2) and performance (Re=10 3 to 2*10 5 ) parameters. Under the influence of Re and of the channel curvature, the heat transfer from both the convex and the concave surfaces for two-side heating (q w1 ≅ q w2 ) is augmented by 20-30% over one-side heating. Improved relations to predict the critical values of Reynolds Re cr1 and Re cr2 are suggested. They enable more exact predictions of the heat transfer from convex surface in transient flows for one-side heating. The relation for annular channels is suggested for the turbulent heat transfer from the convex and concave surfaces of two-side heated helical channels. It can be adapted by introducing earlier expresions for one-side heated helical channels. (author). 6 refs., 2 tabs., 3 figs

Anthropogenic heat fluxes over Moscow agglomeration and other Russian and world cities

Science.gov (United States)

Belova, Iya; Ginzburg, Alexander

2010-05-01

]. References: Ginzburg A., Raspletina N. Anthropogenic heat fluxes estimation for metropolitan areas and urban regions // Geophysical Research Abstracts of EGU General Assembly 2008, Vol. 10, EGU2008-A -02526; SRef-ID: 1607-7962/gra/EGU2008-A-02526. The 2009 Little Green Data Book. 2009. World Bank. Russian regions: Basic city socio-economic indexes. 2008 Statistical digest. Moscow. Rosstat. 2008. 375 p. Martynov A.S., Artyukhov V.V., Vinogradov V.G. Web-atlas: Environment and health of population of Russia. 1997. http://www.sci.aha.ru/ATL/ra32b.htm. Ginzburg A.S., D.P. Gubanova, V.M. Minashkin. 2009. Influence of natural and anthropogenic aerosols on global and regional climate. Russian Journal of General Chemistry, Volume 79, Number 9, pp. 2062-2070.

District heating and heat storage using the solution heat of an ammonia/water system

International Nuclear Information System (INIS)

Taube, M.; Peier, W.; Mayor, J.C.

1976-01-01

The article describes a model for the optimum use of the heat energy generated in a nuclear power station for district heating and heat storage taking account of the electricity and heat demand varying with time. (HR/AK) [de

Winter-regime surface heat loss from heated streams

International Nuclear Information System (INIS)

Paily, P.P.; Macagno, E.O.; Kennedy, J.F.

1974-01-01

Evaluation of the rate of surface heat exchange between the water and air is a significant factor in any study of the thermal response of heated streams to heat inputs. Existing methods to determine the amount of heat transfer across the water surface are surveyed, and the different formulas developed for determining the heat exchange components are compiled. Heat-transfer models that have been proposed in the literature are reviewed, and a new linearized model for determining the rate of surface heat exchange is proposed. Generalized relations between the major climatological factors and the coefficients of the linearized heat-loss rate are established by multiple-regression analysis. The analysis is limited to cold-period conditions, in the sense that air temperatures below the freezing point of water only are considered in developing the regression equations. A computer program, using FORTRAN, is presented which enables the computation of the coefficients appearing in the linearized heat-loss rate for all combinations of the various climatological factors

Nuclear heat for industrial purposes and district heating

International Nuclear Information System (INIS)

1974-01-01

Studies on the various possibilities for the application of heat from nuclear reactors in the form of district heat or process steam for industrial purposes had been made long before the present energy crisis. Although these studies have indicated technical feasibility and economical justification of such utilization, the availability of relatively cheap oil and difficulties in locating a nuclear heat source inside industrial areas did not stimulate much further development. Since the increase of oil prices, the interest in nuclear heat application is reawakened, and a number of new potential areas have been identified. It now seems generally recognized that the heat from nuclear reactors should play an important role in primary energy supply, not only for electricity production but also as direct heat. At present three broad areas of nuclear heat application are identified: Direct heat utilization in industrial processing requiring a temperature above 800 deg. C; Process steam utilization in various industries, requiring a temperature mainly in the range of 200-300 deg. C; Low temperature and waste heat utilization from nuclear power plants for desalination of sea water and district heating. Such classification is mainly related to the type and characteristics of the heat source or nuclear reactor which could be used for a particular application. Modified high temperature reactor types (HTR) are the candidates for direct heat application, while the LWR reactors can satisfy most of the demands for process steam. Production of waste heat is a characteristic of all thermal power plants, and its utilization is a major challenge in the field of power production

Workshop Arboretum Volčji potok

Directory of Open Access Journals (Sweden)

Ana Kučan

2012-01-01

Full Text Available From its constitution onwards, the Volčji Potok Arboretum has been caught between various conflicting orientations. It is both a scientific, research and educational institution, and a cultural monument with exquisite garden and landscape design features and areas of great natural value and built cultural heritage, as well as commercial venue. At the same time, it functions as a park and an area for mass events, a garden centre and nursery. This variety of functions has helped Arboretum to survive the pressures of time; however, partial and uncoordinated interventions have threatened its original mission and its image and generated a number of conflicting situations. The workshop, organised on the initiative of the Institute for the Protection of Cultural Heritage of Slovenia, which involved students from the Faculty of Architecture and students from the Department of Landscape Architecture of the Biotechnical Faculty in mixed groups, generated eight proposals to solve some of the most urgent problems by introducing optimised development with clearly defined goals and priorities.

Author Details

African Journals Online (AJOL)

Abstract · Vol 6, No 1 (2012) - Articles Physical Characteristics of Water Used by Haramaya University and the Effects of Heating and Cooling on the Amount of Extracted Solids Abstract · Vol 8, No 1 (2014) - Articles Comparative Study on Wind Power using Meteorological Data and Wind Turbine Output at Ashogoda Village, ...

The log mean heat transfer rate method of heat exchanger considering the influence of heat radiation

International Nuclear Information System (INIS)

Wong, K.-L.; Ke, M.-T.; Ku, S.-S.

2009-01-01

The log mean temperature difference (LMTD) method is conventionally used to calculate the total heat transfer rate of heat exchangers. Because the heat radiation equation contains the 4th order exponential of temperature which is very complicate in calculations, thus LMTD method neglects the influence of heat radiation. From the recent investigation of a circular duct in some practical situations, it is found that even in the situation of the temperature difference between outer duct surface and surrounding is low to 1 deg. C, the heat radiation effect can not be ignored in the situations of lower ambient convective heat coefficient and greater surface emissivities. In this investigation, the log mean heat transfer rate (LMHTR) method which considering the influence of heat radiation, is developed to calculate the total heat transfer rate of heat exchangers.

Heat pump augmentation of nuclear process heat

International Nuclear Information System (INIS)

Koutz, S.L.

1986-01-01

A system is described for increasing the temperature of a working fluid heated by a nuclear reactor. The system consists of: a high temperature gas cooled nuclear reactor having a core and a primary cooling loop through which a coolant is circulated so as to undergo an increase in temperature, a closed secondary loop having a working fluid therein, the cooling and secondary loops having cooperative association with an intermediate heat exchanger adapted to effect transfer of heat from the coolant to the working fluid as the working fluid passes through the intermediate heat exchanger, a heat pump connected in the secondary loop and including a turbine and a compressor through which the working fluid passes so that the working fluid undergoes an increase in temperature as it passes through the compressor, a process loop including a process chamber adapted to receive a process fluid therein, the process chamber being connected in circuit with the secondary loop so as to receive the working fluid from the compressor and transfer heat from the working fluid to the process fluid, a heat exchanger for heating the working fluid connected to the process loop for receiving heat therefrom and for transferring heat to the secondary loop prior to the working fluid passing through the compressor, the secondary loop being operative to pass the working fluid from the process chamber to the turbine so as to effect driving relation thereof, a steam generator operatively associated with the secondary loop so as to receive the working fluid from the turbine, and a steam loop having a feedwater supply and connected in circuit with the steam generator so that feedwater passing through the steam loop is heated by the steam generator, the steam loop being connected in circuit with the process chamber and adapted to pass steam to the process chamber with the process fluid

Study of selective heating at ion cyclotron resonance for the plasma separation process

International Nuclear Information System (INIS)

Compant La Fontaine, A.; Pashkovsky, V.G.

1995-01-01

The plasma separation process by ion cyclotron resonance heating (ICRH) is studied both theoretically and experimentally on two devices: the first one called ERIC (Ion Cyclotron Resonance Experiment) at Saclay (France) [P. Louvet, Proceedings of the 2nd Workshop on Separation Phenomena in Liquids and Gases, Versailles, France, 1989, edited by P. Louvet, P. Noe, and Soubbaramayer (Centre d'Etudes Nucleaires de Saclay and Cite Scientifique Parcs et Technopoles, Ile de France Sud, France, 1989), Vol. 1, p. 5] and the other one named SIRENA at the Kurchatov Institute, Moscow, Russia [A. I. Karchevskii et al., Plasma Phys. Rep. 19, 214 (1993)]. The radio frequency (RF) transversal magnetic field is measured by a magnetic probe both in plasma and vacuum and its Fourier spectrum versus the axial wave number k z is obtained. These results are in agreement with the electromagnetic (EM) field calculation model based on resolution of Maxwell equations by a time-harmonic scheme studied here. Various axial boundary conditions models used to compute the EM field are considered. The RF magnetic field is weakly influenced by the plasma while the electric field components are strongly disturbed due to space-charge effects. In the plasma the transversal electric field is enhanced and the k z spectrum is narrower than in vacuum. The calculation of the resonant isotope heating is made by the Runge--Kutta method. The influence of ion--ion collisions, inhomogeneity of the static magnetic field B 0 , and the RF transversal magnetic field component on the ion acceleration is examined. These results are successfully compared with experiments of a minor isotope 44 Ca heating measurements, made with an energy analyzer. copyright 1995 American Institute of Physics

Investigation on Solar Heating System with Building-Integrated Heat Storage

DEFF Research Database (Denmark)

Heller, Alfred

1996-01-01

Traditional solar heating systems cover between 5 and 10% of the heat demand fordomestic hot water and comfort heating. By applying storage capacity this share can beincreased much. The Danish producer of solar heating systems, Aidt-Miljø, markets such a system including storage of dry sand heated...... by PP-pipe heat exchanger. Heat demand is reduced due to direct solar heating and due to storage. The storage affects the heat demand passively due to higher temperatures. Hence heat loss is reduced and passive heating is optioned. In theory, by running the system flow backwards, active heating can...... solar collector area of the system, was achieved. Active heating from the sand storage was not observed. The pay-back time for the system can be estimated to be similar to solar heated domestic hot water systems in general. A number of minor improvements on the system could be pointed out....

Heat transfer in an asymmetrically heated duct, 2

International Nuclear Information System (INIS)

Satoh, Isao; Kurosaki, Yasuo

1986-01-01

The objective of this article is to study theoretically and experimentally the effects of nonuniform heating on turbulent heat transfer characteristics for flow in a horizontal rectangular duct ; a vertical side wall was uniformly heated, and the other wall were insulated. In our theoretical approach, the zero-equation model for turbulent eddy viscosity was employed. The effects of mesh size of finite difference on the calculation results were examined, and some refined compensation for wall temperatures and wall shear stresses by no use of fine mesh were proposed to reduce the calculation time. The heat transfer coefficients in thermally developing region for a nonuniformly heated duct obtained from numerical solutions are larger than the one for uniformly heated case. The buoyancy effects on heat transfer were evaluated. However, it was seen that the secondary flow due to buoyancy force was hardly expected to enhance heat transfer in a turbulent duct flow. Experiments were performed to measure the velocity and temperature profiles in a turbulent duct flow with a nonuniform heated wall. The experimental results were in good agreement with the theoretical ones. (author)

Experimental study on heat pipe assisted heat exchanger used for industrial waste heat recovery

International Nuclear Information System (INIS)

Ma, Hongting; Yin, Lihui; Shen, Xiaopeng; Lu, Wenqian; Sun, Yuexia; Zhang, Yufeng; Deng, Na

2016-01-01

Highlights: • A heat pipe heat exchanger (HPHE) was used to recycle the waste heat in a slag cooling process of steel industry. • An specially designed on-line cleaning device was construed and used to enhance the heat transfer of HPHE. • The performance characteristics of a HPHE has been assessed by integrating the first and second law of thermodynamics. • The optimum operation conditions was determined by integrating the first and the second law of thermodynamics. - Abstract: Steel industry plays an important role economically in China. A great amount of hot waste liquids and gases are discharged into environment during many steelmaking processes. These waste liquids and gases have crucial energy saving potential, especially for steel slag cooling process. It could be possible to provide energy saving by employing a waste heat recovery system (WHRS). The optimum operation condition was assessed by integrating the first and the second law of thermodynamics for a water–water heat pipe heat exchanger (HPHE) for a slag cooling process in steel industry. The performance characteristics of a HPHE has been investigated experimentally by analyzing heat transfer rate, heat transfer coefficient, effectiveness, exergy efficiency and number of heat transfer units (NTU). A specially designed on-line cleaning device was used to clean the heat exchange tubes and enhance heat transfer. The results indicated that the exergy efficiency increased with the increment of waste water mass flow rate at constant fresh water mass flow rate, while the effectiveness decreased at the same operation condition. As the waste water mass flow rate varied from 0.83 m"3/h to 1.87 m"3/h, the effectiveness and exergy efficiency varied from 0.19 to 0.09 and from 34% to 41%, respectively. In the present work, the optimal flow rates of waste water and fresh water were 1.20 m"3/h and 3.00 m"3/h, respectively. The on-line cleaning device had an obvious effect on the heat transfer, by performing

Mathematical model for calculation of the heat-hydraulic modes of heating points of heat-supplying systems

Science.gov (United States)

Shalaginova, Z. I.

2016-03-01

The mathematical model and calculation method of the thermal-hydraulic modes of heat points, based on the theory of hydraulic circuits, being developed at the Melentiev Energy Systems Institute are presented. The redundant circuit of the heat point was developed, in which all possible connecting circuits (CC) of the heat engineering equipment and the places of possible installation of control valve were inserted. It allows simulating the operating modes both at central heat points (CHP) and individual heat points (IHP). The configuration of the desired circuit is carried out automatically by removing the unnecessary links. The following circuits connecting the heating systems (HS) are considered: the dependent circuit (direct and through mixing elevator) and independent one (through the heater). The following connecting circuits of the load of hot water supply (HWS) were considered: open CC (direct water pumping from pipelines of heat networks) and a closed CC with connecting the HWS heaters on single-level (serial and parallel) and two-level (sequential and combined) circuits. The following connecting circuits of the ventilation systems (VS) were also considered: dependent circuit and independent one through a common heat exchanger with HS load. In the heat points, water temperature regulators for the hot water supply and ventilation and flow regulators for the heating system, as well as to the inlet as a whole, are possible. According to the accepted decomposition, the model of the heat point is an integral part of the overall heat-hydraulic model of the heat-supplying system having intermediate control stages (CHP and IHP), which allows to consider the operating modes of the heat networks of different levels connected with each other through CHP as well as connected through IHP of consumers with various connecting circuits of local systems of heat consumption: heating, ventilation and hot water supply. The model is implemented in the Angara data

Geothermal heat-pump systems of heat supply

International Nuclear Information System (INIS)

Vasil'ev, G.P.

2004-01-01

The data on the multilayer operation of the objects, located in the climatic conditions of the central area of Russia and equipped with the geothermal heat-pumping systems of the heat supply are presented. The results of the analytical studies on evaluating the geothermal heat-pumping systems of the heat supply integration efficiency into the structure of the energy supply system, prevailing in the country, are presented [ru

Heat supply concept for trade. Vol. 3. Environmentally friendly and energy-saving heat supply for public institutions by private operator models (phase 1). Final report. Vol. 1; Waermelieferungskonzept des Handwerks. Bd. 3. Umweltfreundliche und energiesparende Waermeversorgung oeffentlicher Einrichtungen durch private Betreibermodelle (Phase 1). Abschlussbericht. Berichtsband 1

Energy Technology Data Exchange (ETDEWEB)

Hacker, J [ed.; Biermann, J; Koehler, U; Locke, R; Meyer, K

1993-12-31

Volume 1 of the report indicates two goals: (1): Investigation of the boundary conditions for heat supply models, using the example of the states of Berlin (West) and Niedersachsen. (2): Investigation of the available potential in Berlin (West). (HW) [Deutsch] Der Berichtsband 1 weist 2 Teilziele auf: Teilziel 1: Untersuchung der Rahmenbedingungen fuer Waermelieferungsmodelle am Beispiel des Stadtstaates Berlin (West) und des Flaechenstaates Niedersachsen. Teilziel 2: Potentialermittlung in Berlin (West). (HW)

Loop heat pipes - highly efficient heat-transfer devices for systems of sun heat supply

Energy Technology Data Exchange (ETDEWEB)

Maydanik, Yu. [Ural Branch of the Russian Academy of Sciences, Ekaterinburg (Russian Federation). Inst. of Thermophysics

2004-07-01

Loop heat pipes (LHPs) are hermetic heat-transfer devices operating on a closed evaporation-condensation cycle with the use of capillary pressure for pumping the working fluid [1]. In accordance with this, they possess all the main advantages of conventional heat pipes, but, as distinct from the latter, have a considerably higher heat-transfer capacity, especially when operating in the ''antigravity'' regime, when heat is transferred from above downwards. Besides, LHPs possess a higher functional versatility, are adaptable to different operating conditions and provide great scope for various design embodiments. This is achieved at the expense of both the original design of the device and the properties of the wick - a special capillary structure used for the creation of capillary pressure. The LHP schematic diagram is given in Fig. 1. The device contains an evaporator and a condenser - heat exchanger connected by means of smooth-walled pipe-lines with a relatively small diameter intended for separate motion of vapor and liquid. At present loop heat pipes are most extensively employed in thermoregulation systems of spacecrafts. Miniature LHPs are used for cooling electronics and computers. At the same time there exists a considerable potential of using these devices for the recovery of low-grade (waste) heat from different sources, and also in systems of sun heat supply. In the latter case LHPs may serve as an efficient heat-transfer link between a sun collector and a heat accumulator, which has a low thermal resistance and does not consume any additional energy for pumping the working fluid between them. (orig.)

Numerical analysis of magnetic field effects on hydro-thermal behavior of a magnetic nanofluid in a double pipe heat exchanger

Energy Technology Data Exchange (ETDEWEB)

Shakiba, Ali, E-mail: Shakiba7858@yahoo.com [Department of Mechanical Engineering, Mazandaran Institute of Technology, Babol (Iran, Islamic Republic of); Vahedi, Khodadad, E-mail: Khvahedi@ihu.ac.ir [Department of Mechanical Engineering, Imam Hossein University, Tehran (Iran, Islamic Republic of)

2016-03-15

This study attempts to numerically investigate the hydro-thermal characteristics of a ferrofluid (water and 4 vol% Fe{sub 3}O{sub 4}) in a counter-current horizontal double pipe heat exchanger, which is exposed to a non-uniform transverse magnetic field with different intensities. The magnetic field is generated by an electric current going through a wire located parallel to the inner tube and between two pipes. The single phase model and the control volume technique have been used to study the flow. The effects of magnetic field have been added to momentum equation by applying C++ codes in Ansys Fluent 14. The results show that applying this kind of magnetic field causes kelvin force to be produced perpendicular to the ferrofluid flow, changing axial velocity profile and creating a pair of vortices which leads to an increase in Nusselt number, friction factor and pressure drop. Comparing the enhancement percentage of Nusselt number, friction factor and pressure drop demonstrates that the optimum value of magnetic number for Re{sub ff}=50 is between Mn=1.33×10{sup 6} and Mn=2.37×10{sup 6}. So applying non-uniform transverse magnetic field can control the flow of ferrofluid and improve heat transfer process of double pipe heat exchanger. - Highlights: • Effect of applying non-uniform transverse magnetic field on a ferrofluid for enhancing the cooling process in a double pipe heat exchanger is investigated. • Heat exchanger is exposed to a non-uniform transverse magnetic field with different intensities. • The magnetic field is generated by an electric current going through a wire located parallel to inner tube and between two pipes. • Applying this field produces kelvin force to change axial velocity profile and creating a pair of vortices increasing Nusselt number, friction factor and pressure drop.

Heat transfer

Indian Academy of Sciences (India)

First page Back Continue Last page Overview Graphics. Heat transfer. Heat conduction in solid slab. Convective heat transfer. Non-linear temperature. variation due to flow. HEAT FLUX AT SURFACE. conduction/diffusion.

Component Cooling Heat Exchanger Heat Transfer Capability Operability Monitoring

International Nuclear Information System (INIS)

Mihalina, M.; Djetelic, N.

2010-01-01

The ultimate heat sink (UHS) is of highest importance for nuclear power plant safe and reliable operation. The most important component in line from safety-related heat sources to the ultimate heat sink water body is a component cooling heat exchanger (CC Heat Exchanger). The Component Cooling Heat Exchanger has a safety-related function to transfer the heat from the Component Cooling (CC) water system to the Service Water (SW) system. SW systems throughout the world have been the root of many plant problems because the water source, usually river, lake, sea or cooling pond, are conductive to corrosion, erosion, biofouling, debris intrusion, silt, sediment deposits, etc. At Krsko NPP, these problems usually cumulate in the summer period from July to August, with higher Sava River (service water system) temperatures. Therefore it was necessary to continuously evaluate the CC Heat Exchanger operation and confirm that the system would perform its intended function in accordance with the plant's design basis, given as a minimum heat transfer rate in the heat exchanger design specification sheet. The Essential Service Water system at Krsko NPP is an open cycle cooling system which transfers heat from safety and non-safety-related systems and components to the ultimate heat sink the Sava River. The system is continuously in operation in all modes of plant operation, including plant shutdown and refueling. However, due to the Sava River impurities and our limited abilities of the water treatment, the system is subject to fouling, sedimentation buildup, corrosion and scale formation, which could negatively impact its performance being unable to satisfy its safety related post accident heat removal function. Low temperature difference and high fluid flows make it difficult to evaluate the CC Heat Exchanger due to its specific design. The important effects noted are measurement uncertainties, nonspecific construction, high heat transfer capacity, and operational specifics (e

Heat transfer capability analysis of heat pipe for space reactor

International Nuclear Information System (INIS)

Li Huaqi; Jiang Xinbiao; Chen Lixin; Yang Ning; Hu Pan; Ma Tengyue; Zhang Liang

2015-01-01

To insure the safety of space reactor power system with no single point failures, the reactor heat pipes must work below its heat transfer limits, thus when some pipes fail, the reactor could still be adequately cooled by neighbor heat pipes. Methods to analyze the reactor heat pipe's heat transfer limits were presented, and that for the prevailing capillary limit analysis was improved. The calculation was made on the lithium heat pipe in core of heat pipes segmented thermoelectric module converter (HP-STMC) space reactor power system (SRPS), potassium heat pipe as radiator of HP-STMC SRPS, and sodium heat pipe in core of scalable AMTEC integrated reactor space power system (SAIRS). It is shown that the prevailing capillary limits of the reactor lithium heat pipe and sodium heat pipe is 25.21 kW and 14.69 kW, providing a design margin >19.4% and >23.6%, respectively. The sonic limit of the reactor radiator potassium heat pipe is 7.88 kW, providing a design margin >43.2%. As the result of calculation, it is concluded that the main heat transfer limit of HP-STMC SRPS lithium heat pipe and SARIS sodium heat pipe is prevailing capillary limit, but the sonic limit for HP-STMC SRPS radiator potassium heat pipe. (authors)

Primary energy savings using heat storage for biomass heating systems

Directory of Open Access Journals (Sweden)

Mitrović Dejan M.

2012-01-01

Full Text Available District heating is an efficient way to provide heat to residential, tertiary and industrial users. The heat storage unit is an insulated water tank that absorbs surplus heat from the boiler. The stored heat in the heat storage unit makes it possible to heat even when the boiler is not working, thus increasing the heating efficiency. In order to save primary energy (fuel, the boiler operates on nominal load every time it is in operation (for the purpose of this research. The aim of this paper is to analyze the water temperature variation in the heat storage, depending on the heat load and the heat storage volume. Heat load is calculated for three reference days, with average daily temperatures from -5 to 5°C. The primary energy savings are also calculated for those days in the case of using heat storage in district heating.[Projekat Ministarstva nauke Republike Srbije, br. TR 33051: The concept of sustainable energy supply of settlements with energy efficient buildings

Heat Islands

Science.gov (United States)

EPA's Heat Island Effect Site provides information on heat islands, their impacts, mitigation strategies, related research, a directory of heat island reduction initiatives in U.S. communities, and EPA's Heat Island Reduction Program.

Member for conducting excess heat away from heat sources

International Nuclear Information System (INIS)

Cooke-Yarborough, E.H.

1975-01-01

Should a radioisotope-powered engine (e.g., a Stirling cycle engine for generating electricity) stop working for any reason, the radioisotope heat source will continue to generate heat. This will result in a rise in temperature which may cause overheating of and possible damage to the engine as well as to the heat source itself. The invention provides a support/location member for conducting excess heat from the heat source and which, in normal operation of the engine, will impede the conduction of heat away from the heat source and so reduce thermal losses. The member is of elongated form and comprises a stack of heat-conductive slugs disposed in a tube and in interspaced relationship along the axis of the tube. The tube supports the slugs in axial alignment. Means are provided for attaching an end one of the slugs to the heat source and means operable on overheating of said end one of the slugs are also provided whereby the slugs are able to move into heat-conducting contact with each other so as to conduct the excess heat away from said heat source. The slugs may be brazed to the tube whereby progressive overheating of the slugs along the stack results in an overheated slug being freed from attachment to the tube so as to allow the overheated slug to move along the stack and engage the next slug in line in heat-conducting contact. (U.S.)

Heating great residential units with combustion-motor heat pumps

Energy Technology Data Exchange (ETDEWEB)

Vossen, W

1982-10-01

Economic usage of combustion-motor heat pumps requires: reliable technology and delivery of the heat pump; design and operation. The heat pump must be integrated perfectly into the heating system. This contributions is based on a three-year operational experience with over 150 heat pumps used mainly in residential and administrative buildings (plus commercial buildings, swimming pools, sport centres etc.). These are heat pumps operating on the compression principle with natural gas, liquid gas, or fuel oil.

Evaluation of Excess Heat Utilization in District Heating Systems by Implementing Levelized Cost of Excess Heat

Directory of Open Access Journals (Sweden)

Borna Doračić

2018-03-01

Full Text Available District heating plays a key role in achieving high primary energy savings and the reduction of the overall environmental impact of the energy sector. This was recently recognized by the European Commission, which emphasizes the importance of these systems, especially when integrated with renewable energy sources, like solar, biomass, geothermal, etc. On the other hand, high amounts of heat are currently being wasted in the industry sector, which causes low energy efficiency of these processes. This excess heat can be utilized and transported to the final customer by a distribution network. The main goal of this research was to calculate the potential for excess heat utilization in district heating systems by implementing the levelized cost of excess heat method. Additionally, this paper proves the economic and environmental benefits of switching from individual heating solutions to a district heating system. This was done by using the QGIS software. The variation of different relevant parameters was taken into account in the sensitivity analysis. Therefore, the final result was the determination of the maximum potential distance of the excess heat source from the demand, for different available heat supplies, costs of pipes, and excess heat prices.

Comparison of PM collection efficiency of Gent and Airmatrics MiniVol portable air sampler

International Nuclear Information System (INIS)

Begum, Bilkis A.; Biswas, Swapan K.

2005-01-01

Gent PM sampler was developed as an integral part of several International Atomic Energy Agency sponsored coordinated research programmes (CRP) for collecting air particulate samples. On the other hand, the MiniVol Portable Air Sampler is a commercial ambient air sampler for particulate matter and non-reactive gases used by different agencies. Air quality management system requires comparable air quality data to be collected by different stake holders for assessment and regulatory purposes. In order to compare the characteristics of Gent sampler with the MiniVol Portable Air Sampler, the reproducibility of the sample mass collection efficiency were examined and the measured mass concentrations were compared. It was found that in case of PM 10 both samplers collect almost same fraction of PM 10 mass when the Gent sampler was operated at 16 litre per minute flow rate. But in case of fine fraction, Portable sampler collects 70% higher PM 2.5 mass concentration compared to the Gent PM 2.2 mass concentrations. This is because, the Gent sampler was typically operated at 16 to 17 lpm resulting in an estimated 50% cut point of 2.2 μm.(author)

Phase change heat transfer device for process heat applications

International Nuclear Information System (INIS)

Sabharwall, Piyush; Patterson, Mike; Utgikar, Vivek; Gunnerson, Fred

2010-01-01

The next generation nuclear plant (NGNP) will most likely produce electricity and process heat, with both being considered for hydrogen production. To capture nuclear process heat, and transport it to a distant industrial facility requires a high temperature system of heat exchangers, pumps and/or compressors. The heat transfer system is particularly challenging not only due to the elevated temperatures (up to ∼1300 K) and industrial scale power transport (≥50 MW), but also due to a potentially large separation distance between the nuclear and industrial plants (100+ m) dictated by safety and licensing mandates. The work reported here is the preliminary analysis of two-phase thermosyphon heat transfer performance with alkali metals. A thermosyphon is a thermal device for transporting heat from one point to another with quite extraordinary properties. In contrast to single-phased forced convective heat transfer via 'pumping a fluid', a thermosyphon (also called a wickless heat pipe) transfers heat through the vaporization/condensing process. The condensate is further returned to the hot source by gravity, i.e., without any requirement of pumps or compressors. With this mode of heat transfer, the thermosyphon has the capability to transport heat at high rates over appreciable distances, virtually isothermally and without any requirement for external pumping devices. Two-phase heat transfer by a thermosyphon has the advantage of high enthalpy transport that includes the sensible heat of the liquid, the latent heat of vaporization, and vapor superheat. In contrast, single-phase forced convection transports only the sensible heat of the fluid. Additionally, vapor-phase velocities within a thermosyphon are much greater than single-phase liquid velocities within a forced convective loop. Thermosyphon performance can be limited by the sonic limit (choking) of vapor flow and/or by condensate entrainment. Proper thermosyphon requires analysis of both.

Performance of heat engines with non-zero heat capacity

International Nuclear Information System (INIS)

Odes, Ron; Kribus, Abraham

2013-01-01

Highlights: ► Finite heat capacity is a second irreversibility mechanism in addition to thermal resistance. ► Heat capacity introduces thermal transients and reverse heat flow. ► Engine maximum power and efficiency are lower for finite heat capacity. ► Implementing the optimal engine cycle requires active control. - Abstract: The performance of a heat engine is analyzed subject to two types of irreversibility: a non-zero heat capacity, together with the more common finite heat transfer rate between the engine and the external heat reservoirs. The heat capacity represents an engine body that undergoes significant temperature variations during the engine cycle. An option to cut off the heat exchange between the engine and the external surrounding for part of the engine cycle is also explored. A variational approach was taken to find the engine’s internal temperature profile (which defines the internal thermodynamic cycle) that would produce maximum power. The maximum power is shown to be lower than the case of zero heat capacity, due to a loss of heat that is stored in the engine body and then lost, bypassing the thermodynamic cycle. The maximum efficiency and the efficiency at maximum power are also lower than the zero heat capacity case. Similar to the Curzon–Ahlborn analysis, power can be traded for increased efficiency, but for high heat capacity, the range of efficiency that is available for such a trade is diminished. Isolating the engine during part of the cycle reduces maximum power, but the efficiency at maximum power and the maximum efficiency are improved, due to better exploitation of heat stored in the engine body. This might be useful for real engines that are limited by the internal energy change during a single engine cycle or by the operating frequency, leading to a broader power–efficiency curve.

Segmented heat exchanger

Science.gov (United States)

Baldwin, Darryl Dean; Willi, Martin Leo; Fiveland, Scott Byron; Timmons, Kristine Ann

2010-12-14

A segmented heat exchanger system for transferring heat energy from an exhaust fluid to a working fluid. The heat exchanger system may include a first heat exchanger for receiving incoming working fluid and the exhaust fluid. The working fluid and exhaust fluid may travel through at least a portion of the first heat exchanger in a parallel flow configuration. In addition, the heat exchanger system may include a second heat exchanger for receiving working fluid from the first heat exchanger and exhaust fluid from a third heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the second heat exchanger in a counter flow configuration. Furthermore, the heat exchanger system may include a third heat exchanger for receiving working fluid from the second heat exchanger and exhaust fluid from the first heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the third heat exchanger in a parallel flow configuration.

Heat Waves

Science.gov (United States)

Heat Waves Dangers we face during periods of very high temperatures include: Heat cramps: These are muscular pains and spasms due ... that the body is having trouble with the heat. If a heat wave is predicted or happening… - ...

Experimental investigation of a manifold heat-pipe heat exchanger

International Nuclear Information System (INIS)

Konev, S.V.; Wang Tszin' Lyan'; D'yakov, I.I.

1995-01-01

Results of experimental investigations of a heat exchanger on a manifold water heat pipe are given. An analysis is made of the temperature distribution along the heat-transfer agent path as a function of the transferred heat power. The influence of the degree of filling with the heat transfer agent on the operating characteristics of the construction is considered

Heat pumps

CERN Document Server

Brodowicz, Kazimierz; Wyszynski, M L; Wyszynski

2013-01-01

Heat pumps and related technology are in widespread use in industrial processes and installations. This book presents a unified, comprehensive and systematic treatment of the design and operation of both compression and sorption heat pumps. Heat pump thermodynamics, the choice of working fluid and the characteristics of low temperature heat sources and their application to heat pumps are covered in detail.Economic aspects are discussed and the extensive use of the exergy concept in evaluating performance of heat pumps is a unique feature of the book. The thermodynamic and chemical properties o

Author Details

African Journals Online (AJOL)

Author Details. Journal Home > Advanced Search > Author Details. Log in or Register to get access to full text downloads. ... Abstract PDF · Vol 3, No 6 (2011) - Articles Mixed convection flow and heat transfer in a vertical wavy channel containing porous and fluid layer with traveling thermal waves. Abstract PDF · Vol 3, No 8 ...

Browse Title Index

African Journals Online (AJOL)

Items 201 - 250 of 283 ... Vol 4, No 2 (2004), Rare Gases in mantle-derived rocks from Annobon Island: Preliminary step-heating helium results, Abstract PDF. FT Aka, M Kusakabe, K Nagao, G Tanyileke, J Nnange, N Nfomou. Vol 4, No 2 (2004), Rétention de Escherichia coli d'un eau d'infiltration en sol équatorial au ...

Heat pumps in combined heat and power systems

DEFF Research Database (Denmark)

Ommen, Torben Schmidt; Markussen, Wiebke Brix; Elmegaard, Brian

2014-01-01

Heat pumps have previously been proposed as a way to integrate higher amounts of renewable energy in DH (district heating) networks by integrating, e.g., wind power. The paper identifies and compares five generic configurations of heat pumps in DH systems. The operational performance...... of the considered cases. When considering a case where the heat pump is located at a CHP (combined heat and power) plant, a configuration that increases the DH return temperature proposes the lowest operation cost, as low as 12 EUR MWh-1 for a 90 °C e 40 °C DH network. Considering the volumetric heating capacity......, a third configuration is superior in all cases. Finally, the three most promising heat pump configurations are integrated in a modified PQ-diagram of the CHP plant. Each show individual advantages, and for two, also disadvantages in order to achieve flexible operation....

Study of an innovative ejector heat pump-boosted district heating system

International Nuclear Information System (INIS)

Zhang, Bo; Wang, Yuanchao; Kang, Lisha; Lv, Jinsheng

2013-01-01

An Ejector heat pump-boosted District Heating (EDH) system is proposed to improve the heating capacity of existing district heating systems with Combined Heat and Power (CHP). In the EDH, two ejector heat pumps are installed: a primary heat pump (HP 1 ) at the heating station and a secondary heat pump (HP 2 ) at the heating substation. With the EDH, the low-grade waste heat from circulating cooling water in the CHP is recycled and the temperature difference between the water supply and the return of the primary heating network is increased. A thermodynamic model was provided. An experimental study was carried out for both HP 1 and HP 2 to verify the predicting performance. The results show that the COP of HP 1 can reach 1.5–1.9, and the return water temperature of the primary heating network could be decreased to 35 °C with HP 2 . A typical case study for the EDH was analyzed. -- Highlights: • An ejector heat pump-boosted district heating (EDH) is proposed. • The 1st ejector heat pump in EDH recycles heat from cooling water of the CHP. • The 2nd ejector heat pump in EDH boosts the thermal energy utilization of the primary heating network. • Modeling and experimental studies are presented

Heat exchanger network retrofit optimization involving heat transfer enhancement

International Nuclear Information System (INIS)

Wang Yufei; Smith, Robin; Kim, Jin-Kuk

2012-01-01

Heat exchanger network retrofit plays an important role in energy saving in process industry. Many design methods for the retrofit of heat exchanger networks have been proposed during the last three decades. Conventional retrofit methods rely heavily on topology modifications which often result in a long retrofit duration and high initial costs. Moreover, the addition of extra surface area to the heat exchanger can prove difficult due to topology, safety and downtime constraints. Both of these problems can be avoided through the use of heat transfer enhancement in heat exchanger network retrofit. This paper presents a novel design approach to solve heat exchanger network retrofit problems based on heat transfer enhancement. An optimisation method based on simulated annealing has been developed to find the appropriate heat exchangers to be enhanced and to calculate the level of enhancement required. The physical insight of enhanced exchangers is also analysed. The new methodology allows several possible retrofit strategies using different retrofit methods be determined. Comparison of these retrofit strategies demonstrates that retrofit modification duration and payback time are reduced when heat transfer enhancement is utilised. Heat transfer enhancement can be also used as a substitute for increased heat exchanger network surface area to reduce retrofit investment costs.

Specific heat, polarization and heat conduction in microwave heating systems: A nonequilibrium thermodynamic point of view

International Nuclear Information System (INIS)

Bergese, Paolo

2006-01-01

A microwave (MW) field can induce in a dielectric material an oscillatory polarization. By this mechanism part of the energy carried by the waves is converted into chaotic agitation, and the material heats up. MW heating is a nonequilibrium phenomenon, while conventional heating can generally be considered as quasi-static. Excess (or nonthermal) effects of MWs with respect to conventional heating lie in this difference. Macroscopically, MW heating can be described in the framework of linear nonequilibrium thermodynamics (NET). This approach indicates that in a dielectric material under MW heating the specific heat has a dynamic component linked to the variation of polarization with temperature, and that polarization and heat conduction are intertwined. In particular, linear NET provides a new phenomenological equation for heat conduction that is composed of the classic Fourier's law and an additional term due to polarization relaxation. This term quantitatively describes the excess effect of MWs on thermal conduction

HEATING-7, Multidimensional Finite-Difference Heat Conduction Analysis

International Nuclear Information System (INIS)

2000-01-01

1 - Description of program or function: HEATING 7.2i and 7.3 are the most recent developments in a series of heat-transfer codes and obsolete all previous versions distributed by RSICC as SCA-1/HEATING5 and PSR-199/HEATING 6. Note that Unix and PC versions of HEATING7 are available in the CCC-545/SCALE 4.4 package. HEATING can solve steady-state and/or transient heat conduction problems in one-, two-, or three-dimensional Cartesian, cylindrical, or spherical coordinates. A model may include multiple materials, and the thermal conductivity, density, and specific heat of each material may be both time- and temperature-dependent. The thermal conductivity may also be anisotropic. Materials may undergo change of phase. Thermal properties of materials may be input or may be extracted from a material properties library. Heat- generation rates may be dependent on time, temperature, and position, and boundary temperatures may be time- and position-dependent. The boundary conditions, which may be surface-to-environment or surface-to-surface, may be specified temperatures or any combination of prescribed heat flux, forced convection, natural convection, and radiation. The boundary condition parameters may be time- and/or temperature-dependent. General gray body radiation problems may be modeled with user-defined factors for radiant exchange. The mesh spacing may be variable along each axis. HEATING uses a run-time memory allocation scheme to avoid having to recompile to match memory requirements for each specific problem. HEATING utilizes free-form input. In June 1997 HEATING 7.3 was added to the HEATING 7.2i packages, and the Unix and PC versions of both 7.2i and 7.3 were merged into one package. HEATING 7.3 is being released as a beta-test version; therefore, it does not entirely replace HEATING 7.2i. There is no published documentation for HEATING 7.3; but a listing of input specifications, which reflects changes for 7.3, is included in the PSR-199 documentation. For 3-D

Identificación de los compuestos volátiles de frutos de papaya sin ovipositar y ovipositados por toxotrypana curvicauda (diptera: tephritidae).

OpenAIRE

Ruiz Gómez, Olga Lidia

2016-01-01

En los tefrítidos la búsqueda, localización y aceptación del hospedero, depende generalmente de estímulos químicos que pueden ser identificados por las hembras a la distancia. La emisión de compuestos volátiles del fruto, puede cambiar con la oviposición y modificar la atracción de las hembras. En el presente estudio se evaluó la atracción de hembras grávidas de Toxotrypana curvicauda hacia frutos de papaya sin ovipositar y ovipositados y se identificaron los compuestos volátiles de los fruto...

effect of brinkman number and magnetic field on laminar convection ...

African Journals Online (AJOL)

Joseph et al.

Science World Journal Vol 12(No 4) 2017 ... Joule heating on the fully developed MHD flow with heat transfer .... fluid in a vertical parallel – plate with effect of magnetic field and ..... Plates Channel, Proceedings of the 2013 International.

51. Meeting of the Chemical Societies: Almanac of Contributions, Vol. Program, 1, 2, 3, 4 Molecular Models (Workshop); 51. Zjazd chemickych spolocnosti: Zbornik prispevkov, Diel: Program, 1, 2, 3, 4 Molekulove modely (Workshop)

Energy Technology Data Exchange (ETDEWEB)

Uher, M [ed.; Dept. of Org. Chem., Slovak Techn. Univ., Bratislava (Slovakia); Benes, P [ed.; Dept. Nucl. Chem., Czech Techn. Univ., Prague (Czech Republic); Carsky, J [ed.; Inst. of Med. Chem., Biochem. and Clin. Biochem., Comenius Univ., Bratislava (Slovakia); Ctrnactova, H [ed.; Dept. of Educat. and Didactics of Chem., Charles Univ., Prague (Czech Republic); Fecenko, J [ed.; Dept. of Agricult. Chem. and Susten. of Veget., Slovak Agricult. Univ., Nitra (Slovakia); Fellner, P [ed.; Dept. of Inorg. Chem., Slovak Techn. Univ., Bratislava (Slovakia); Hodul, P [ed.; Dept. of Fibres and Textile, Slovak Techn. Univ., Bratislava (Slovakia); Koprda, V [ed.; Dept. of Envir., Slovak Techn. Univ., Bratislava (Slovakia); Kratochvil, B [ed.; Inst. of. Solid State Chem., Chem. Univ., Prague (Czech Republic); Krkoska, P [ed.; Dept. of Chem. Technol. of Wood, Pulp and Paper, Slovak Techn. Univ., Bratislava (Slovakia); Kuruc, J [ed.; Dept. of Nucl. Chem., Comenius Univ., Bratislava (Slovakia); Lehotay, J [ed.; Dept. of Anal. Chem., Slovak Techn. Univ., Bratislava (Slovakia); Matousek, J [ed.; Inst. of Chem. and Technol. of the Envir., Techn. Univ, Brno (Czech Republic); Milichovsky, P [ed.; Dept. of Chem. Techn. of Wood, Pulp and Paper, Univ. Pardubice, Pardubice (Czech Republic); Omastova, M [ed.; Inst. of Polym., SAS, Bratislava (Slovakia); Petrus, L jr; Petrus, L sr [eds.; Inst. of Chem., SAS, Bratislava (Slovakia); Salisova, M [ed.; Dept. of Org. Chem., Comenius Univ., Bratislava (Slovakia); Schwendt, P [ed.; Dept. of Inorg. Chem., Comenius Univ., Bratislava (Slovakia); Silny, P; Sevcik, P; Toma, S [eds.; Comenius Univ., Bratislava (Slovakia); Uherova, R [ed.; Slovak Techn. Univ., Bratislava (Slovakia); Vanek, L [ed.; Charles Univ., Prague (Czech Republic); Zachar, P [ed.; Chem. Univ., Prague (Czech Republic)

1999-09-01

The publication has been set up as a abstracts of the meeting dealing with different chemical problems. The book (Vol. 1) consists of the sections: All-plenary lectures (9 papers); (D) History of the chemistry (14); (K) Didactics of chemistry (32); The book (Vol. 2) consists of the sections: (A) Analytical chemistry (48); (B) Inorganic chemistry (75); (C) Physical chemistry (27); (F) Nuclear chemistry and radioecology (12); (L) Environmental chemistry and toxicology (33); (M) Agricultural chemistry (20). The book (Vol. 3) consists of the sections: (E) Wood, pulp, paper (15); (G) Macromolecular chemistry (42); (H) Organic chemistry, bio-organic chemistry and pharmaceutical chemistry (96); (I) Food chemistry and biochemistry (34); (J) Textile, fibres and foil materials (9). The book (Vol. 4) consists of the workshop Molecular models (3 papers)

District heating grid of the Daqing Nuclear Heating Plant

Energy Technology Data Exchange (ETDEWEB)

Changwen, Ma [Institute of Nuclear Energy and Technology, Tsingua Univ., Beijing (China)

1997-09-01

The Daqing Nuclear Heating Plant is the first commercial heating plant to be built in China. The plant is planned to be used as the main heat resource of one residential quarter of Daqing city. The main parameters of the heating plant are summarized in the paper. The load curve shows that the capacity of the NHP is about 69% of total capacity of the grid. The 12 existing boilers can be used as reserve and peak load heat resources. Two patterns of load following have have been considered and tested on the 5MW Test Heating Reactor. Experiment shows load of heat grid is changed slowly, so automatic load following is not necessary. (author). 9 figs, 1 tab.

Book review: Vetter, H. 2005. Terralog. Turtles of the World. Vol. 3. Central and South America

Directory of Open Access Journals (Sweden)

2006-12-01

Full Text Available Book review: Vetter, H. 2005. Terralog. Turtles of the World. Vol. 3. Central and South America/Schildkröten der Welt Band 3. Mittel- und Südamerika: 1-128, color pictures 606 + 9. Edition Chimaira, Frankfurt, Germany.ISBN 3-930612-82-8; 29.7 x 20.8 cm

Heat planning for fossil-fuel-free district heating areas with extensive end-use heat savings

DEFF Research Database (Denmark)

Harrestrup, Maria; Svendsen, S.

2014-01-01

is a theoretical investigation of the district heating system in the Copenhagen area, in which heat conservation is related to the heat supply in buildings from an economic perspective. Supplying the existing building stock from low-temperature energy resources, e.g. geothermal heat, might lead to oversized......The Danish government plans to make the Danish energy system to be completely free of fossil fuels by 2050 and that by 2035 the energy supply for buildings and electricity should be entirely based on renewable energy sources. To become independent from fossil fuels, it is necessary to reduce...... the energy consumption of the existing building stock, increase energy efficiency, and convert the present heat supply from fossil fuels to renewable energy sources. District heating is a sustainable way of providing space heating and domestic hot water to buildings in densely populated areas. This paper...

Measuring attachment to life in old age: the Portuguese version of the Positive Valuation of Life Scale (Positive VOL).

Science.gov (United States)

Araújo, Lia; Ribeiro, Oscar; Teixeira, Laetitia; Azevedo, Maria João; Jopp, Daniela S; Rott, Christoph; Paúl, Constança

2015-10-01

This study aims to present the psychometric properties of the Portuguese version of the Positive Valuation of Life Scale (Lawton et al. in J Aging Ment Healt 13:3-31, 2001). Sample included 207 community-dwelling elders (129 women; M Age = 77.2 years, SD = 7.5). The data collection included the translated and adapted Portuguese version of Positive Valuation of Life Scale, Life Satisfaction Index Z, Meaning in Life Questionnaire and Geriatric Depression Scale. From exploratory factor analysis, two factors emerged, existential beliefs and perceived control, explaining 49 % of the total variance. Both factors were positively related with meaning in life and life satisfaction and negatively related with depression (p 0.75). The Portuguese version of Positive VOL Scale represents a reliable and valid measure to capture the subjective experience of attachment to one's life. The two-factor structure is an update to Lawton's previous work and in line with findings obtained in the USA (Dennis et al. in What is valuation of life for frail community-dwelling older adults: factor structure and criterion validity of the VOL, Thomas Jefferson University, Center for Applied Research on Aging and Health Research, 2005) and Japan (Nakagawa et al. in Shinrigaku Kenkyu 84:37-46, 2013). Future research is required to investigate VOL predictors and the potential changes toward the end of the life span.

Industrial waste heat utilization for low temperature district heating

International Nuclear Information System (INIS)

Fang, Hao; Xia, Jianjun; Zhu, Kan; Su, Yingbo; Jiang, Yi

2013-01-01

Large quantities of low grade waste heat are discharged into the environment, mostly via water evaporation, during industrial processes. Putting this industrial waste heat to productive use can reduce fossil fuel usage as well as CO 2 emissions and water dissipation. The purpose of this paper is to propose a holistic approach to the integrated and efficient utilization of low-grade industrial waste heat. Recovering industrial waste heat for use in district heating (DH) can increase the efficiency of the industrial sector and the DH system, in a cost-efficient way defined by the index of investment vs. carbon reduction (ICR). Furthermore, low temperature DH network greatly benefits the recovery rate of industrial waste heat. Based on data analysis and in-situ investigations, this paper discusses the potential for the implementation of such an approach in northern China, where conventional heat sources for DH are insufficient. The universal design approach to industrial-waste-heat based DH is proposed. Through a demonstration project, this approach is introduced in detail. This study finds three advantages to this approach: (1) improvement of the thermal energy efficiency of industrial factories; (2) more cost-efficient than the traditional heating mode; and (3) CO 2 and pollutant emission reduction as well as water conservation. -- Highlights: •We review situation of industrial waste heat recovery with a global perspective. •We present a way to analyze the potential to utilize industrial waste heat for DH. •Northern China has huge potential for using low-grade industrial waste heat for DH. •A demonstration project is introduced using the universal approach we propose. •It proves huge benefits for factories, heat-supply companies and the society

Direct Heat

Energy Technology Data Exchange (ETDEWEB)

Lienau, P J

1990-01-01

Potential resources and applications of earth heat in the form of geothermal energy are large. United States direct uses amount to 2,100 MWt thermal and worldwide 8,850 MWt above a reference temperature of 35 degrees Celsius. Space and district heating are the major direct uses of geothermal energy. Equipment employed in direct use projects is of standard manufacture and includes downhole and circulation pumps, transmission and distribution pipelines, heat exchangers and convectors, heat pumps and chillers. Direct uses of earth heat discussed are space and district heating, greenhouse heating and fish farming, process and industrial applications. The economic feasibility of direct use projects is governed by site specific factors such as location of user and resource, resource quality, system load factor and load density, as well as financing. Examples are presented of district heating in Klamath Falls, and Elko. Further developments of direct uses of geothermal energy will depend on matching user needs to the resource, and improving load factors and load density.

Heat transfer

International Nuclear Information System (INIS)

Saad, M.A.

1985-01-01

Heat transfer takes place between material systems as a result of a temperature difference. The transmission process involves energy conversions governed by the first and second laws of thermodynamics. The heat transfer proceeds from a high-temperature region to a low-temperature region, and because of the finite thermal potential, there is an increase in entropy. Thermodynamics, however, is concerned with equilibrium states, which includes thermal equilibrium, irrespective of the time necessary to attain these equilibrium states. But heat transfer is a result of thermal nonequilibrium conditions, therefore, the laws of thermodynamics alone cannot describe completely the heat transfer process. In practice, most engineering problems are concerned with the rate of heat transfer rather than the quantity of heat being transferred. Resort then is directed to the particular laws governing the transfer of heat. There are three distinct modes of heat transfer: conduction, convection, and radiation. Although these modes are discussed separately, all three types may occur simultaneously

High-performance heat pipes for heat recovery applications

Science.gov (United States)

Saaski, E. W.; Hartl, J. H.

1980-01-01

Methods to improve the performance of reflux heat pipes for heat recovery applications were examined both analytically and experimentally. Various models for the estimation of reflux heat pipe transport capacity were surveyed in the literature and compared with experimental data. A high transport capacity reflux heat pipe was developed that provides up to a factor of 10 capacity improvement over conventional open tube designs; analytical models were developed for this device and incorporated into a computer program HPIPE. Good agreement of the model predictions with data for R-11 and benzene reflux heat pipes was obtained.

Heat transfer enhancement for fin-tube heat exchanger using vortex generators

International Nuclear Information System (INIS)

Yoo, Seong Yeon; Park, Dong Seong; Chung, Min Ho; Lee, Sang Yun

2002-01-01

Vortex generators are fabricated on the fin surface of a fin-tube heat exchanger to augment the convective heat transfer. In addition to horseshoe vortices formed naturally around the tube of the fin-tube heat exchanger, longitudinal vortices are artificially created on the fin surface by vortex generators. The purpose of this study is to investigate the local heat transfer phenomena in the fin-tube heat exchangers with and without vortex generators, and to evaluate the effect of vortices on the heat transfer enhancement. Naphthalene sublimation technique is employed to measure local mass transfer coefficients, then analogy equation between heat and mass transfer is used to calculate heat transfer coefficients. Experiments are performed for the model of fin-circular tube heat exchangers with and without vortex generators, and of fin-flat tube heat exchangers with and without vortex generators. Average heat transfer coefficients of fin-flat tube heat exchanger without vortex generator are much lower than those of fin-circular tube heat exchanger. On the other hand, fin-flat tube heat exchanger with vortex generators has much higher heat transfer value than conventional fin-circular tube heat exchanger. At the same time, pressure losses for four types of heat exchanger is measured and compared

Simultaneousness of room heating and ventilation air heating

International Nuclear Information System (INIS)

Mathisen, Hans Martin

2006-01-01

The report is part of NTNU-SINTEF's Smart Buildings program, Smart Energy Efficient Buildings (2002-2006), subprogram 3.1 Heating, ventilation and cooling systems. An important part of this subprogram is the development and implementation of heating distribution systems with low return temperature. A comparison has been made of the simultaneousness of room heating and ventilation air heating in six buildings. Existing measuring data with hourly measurements of effect requirements for the different purposes have been employed. Based on the measuring data the relation between the requirements for room heating and ventilation is estimated. A 'fictitious' return temperature has also been estimated. The result shows a significant variation between the buildings. For all there are short periods where the efficiency need for room heating and ventilation is equal (ml)

Selection of Rational Heat Transfer Intensifiers in the Heat Exchanger

Directory of Open Access Journals (Sweden)

S. A. Burtsev

2016-01-01

Full Text Available The paper considers the applicability of different types of heat transfer intensifiers in the heat exchange equipment. A review of the experimental and numerical works devoted to the intensification of the dimpled surface, surfaces with pins and internally ribbed surface were presented and data on the thermal-hydraulic characteristics of these surfaces were given. We obtained variation of thermal-hydraulic efficiency criteria for 4 different objective functions and 15 options for the intensification of heat transfer. This makes it possible to evaluate the advantages of the various heat transfer intensifiers. These equations show influence of thermal and hydraulic characteristics of the heat transfer intensifiers (the values of the relative heat transfer and drag coefficients on the basic parameters of the shell-and-tube heat exchanger: the number and length of the tubes, the volume of the heat exchanger matrix, the coolant velocity in the heat exchanger matrix, coolant flow rate, power to pump coolant (or pressure drop, the amount of heat transferred, as well as the average logarithmic temperature difference. The paper gives an example to compare two promising heat transfer intensifiers in the tubes and shows that choosing the required efficiency criterion to search for optimal heat exchanger geometry is of importance. Analysis is performed to show that a dimpled surface will improve the effectiveness of the heat exchanger despite the relatively small value of the heat transfer intensification, while a significant increase in drag of other heat transfer enhancers negatively affects their thermalhydraulic efficiency. For example, when comparing the target functions of reducing the heat exchanger volume, the data suggest that application of dimpled surfaces in various fields of technology is possible. But there are also certain surfaces that can reduce the parameters of a heat exchanger. It is shown that further work development should be aimed at

Low grade waste heat recovery using heat pumps and power cycles

International Nuclear Information System (INIS)

Bor, D.M. van de; Infante Ferreira, C.A.; Kiss, Anton A.

2015-01-01

Thermal energy represents a large part of the global energy usage and about 43% of this energy is used for industrial applications. Large amounts are lost via exhaust gases, liquid streams and cooling water while the share of low temperature waste heat is the largest. Heat pumps upgrading waste heat to process heat and cooling and power cycles converting waste heat to electricity can make a strong impact in the related industries. The potential of several alternative technologies, either for the upgrading of low temperature waste heat such as compression-resorption, vapor compression and trans-critical heat pumps, or for the conversion of this waste heat by using organic Rankine, Kalina and trilateral cycle engines, are investigated with regards to energetic and economic performance by making use of thermodynamic models. This study focuses on temperature levels of 45–60 °C as at this temperature range large amounts of heat are rejected to the environment but also investigates the temperature levels for which power cycles become competitive. The heat pumps deliver 2.5–11 times more energy value than the power cycles in this low temperature range at equal waste heat input. Heat engines become competitive with heat pumps at waste heat temperatures at 100 °C and above. - Highlights: • Application of heat pump technology for heating and cooling. • Compression resorption heat pumps operating with large glides approaching 100 K. • Compression-resorption heat pumps with wet compression. • Potential to convert Industrial waste heat to power or high grade heat. • Comparison between low temperature power cycles and heat pumps

Ion and electron heating in ICRF heating experiments on LHD

Energy Technology Data Exchange (ETDEWEB)

Saito, K. [Nagoya Univ. (Japan). Faculty of Engineering; Kumazawa, R.; Mutoh, T. [National Inst. for Fusion Science, Toki, Gifu (Japan)] [and others

2001-02-01

This paper reports on the Ion Cyclotron Range of Frequency (ICRF) heating conducted in 1999 in the 3rd experimental campaign on the Large Helical Device (LHD) with an emphasis on the optimization of the heating regime. Specifically, an exhaustive study of seven different heating regimes was carried out by changing the RF frequency relative to the magnetic field intensity, and the dependence of the heating efficiency on H-minority concentration was investigated. It was found in the experiment that both ion and electron heating are attainable with the same experimental setup by properly choosing the frequency relative to the magnetic field intensity. In the cases of both electron heating and ion heating, the power absorption efficiency depends on the minority ion concentration. An optimum minority concentration exists in the ion heating case while, in the electron heating case, the efficiency increases with concentration monotonically. A simple model calculation is introduced to provide a heuristic understanding of these experimental results. Among the heating regimes examined in this experiment, one of the ion heating regimes was finally chosen as the optimized heating regime and various high performance discharges were realized with it. (author)

Solar-powered Rankine heat pump for heating and cooling

Science.gov (United States)

Rousseau, J.

1978-01-01

The design, operation and performance of a familyy of solar heating and cooling systems are discussed. The systems feature a reversible heat pump operating with R-11 as the working fluid and using a motor-driven centrifugal compressor. In the cooling mode, solar energy provides the heat source for a Rankine power loop. The system is operational with heat source temperatures ranging from 155 to 220 F; the estimated coefficient of performance is 0.7. In the heating mode, the vapor-cycle heat pump processes solar energy collected at low temperatures (40 to 80 F). The speed of the compressor can be adjusted so that the heat pump capacity matches the load, allowing a seasonal coefficient of performance of about 8 to be attained.

Heat transfer analysis of short helical borehole heat exchangers

International Nuclear Information System (INIS)

Zarrella, Angelo; De Carli, Michele

2013-01-01

Highlights: ► Vertical ground heat exchanger with a helical shaped pipe is analyzed. ► The model considers the interaction between the ground and the environment. ► The results of the model are in good agreement with the experimental values. ► The weather conditions considerably affect the fluid heat carrier temperature. ► The pitch between the turns does not affect the behaviour of the heat exchanger. -- Abstract: In this paper a numerical model to analyze the thermal behaviour of vertical ground heat exchangers with a helical shaped pipe is presented. This type of configuration can be a suitable alternative to conventional ground heat exchangers, especially when the heating and cooling loads of the building are very low. The model describes the heat transfer problem by means of a network of interconnected thermal resistances and capacitances. Moreover, as the investigated ground heat exchanger is usually installed in shallow depth, the model takes into account the interaction between the ground and the ambient environment which affects the fluid heat carrier temperature into the heat exchanger and, as a consequence, the energy efficiency of the heat pump. After a sensitivity analysis on the mesh parameters, the presented model is compared with experimental data and the simulation results show good agreement with the measurements. Finally, analyses to investigate the influence of the weather conditions, of the axial heat transfer and of the pitch between the turns of the helical pipe for two types of ground are carried out.

Generalized irreversible heat-engine experiencing a complex heat-transfer law

International Nuclear Information System (INIS)

Chen Lingen; Li Jun; Sun Fengrui

2008-01-01

The fundamental optimal relation between optimal power-output and efficiency of a generalized irreversible Carnot heat-engine is derived based on a generalized heat-transfer law, including a generalized convective heat-transfer law and a generalized radiative heat-transfer law, q ∝ (ΔT n ) m . The generalized irreversible Carnot-engine model incorporates several internal and external irreversibilities, such as heat resistance, bypass heat-leak, friction, turbulence and other undesirable irreversibility factors. The added irreversibilities, besides heat resistance, are characterized by a constant parameter and a constant coefficient. The effects of heat-transfer laws and various loss terms are analyzed. The results obtained corroborate those in the literature

Overall conductance and heat transfer area minimization of refrigerators and heat pumps with finite heat reservoirs

International Nuclear Information System (INIS)

Sarkar, J.; Bhattacharyya, Souvik

2007-01-01

In the present study, the overall conductance and the overall heat transfer area per unit capacity of refrigeration and heat pump systems have been minimized analytically considering both internal and external irreversibilities with variable temperature (finite capacity) heat reservoirs. Hot and cold side refrigerant temperatures, conductance and heat transfer area ratios have been optimized to attain this goal. The results have been verified with the more elaborate numerical optimization results obtained for ammonia based vapour compression refrigeration and heat pump systems working with variable temperature reservoirs. It is observed that the analytical results for optimum refrigerant temperatures, minimum overall conductance and heat transfer area deviate marginally from the numerically optimized results (within 1%), if one assumes a constant heat rejection temperature. The deviation of minimum overall conductance and heat transfer area is more (about 20%), if one considers both the desuperheating and condensation regions separately. However, in the absence of complex and elaborate numerical models, the simple analytical results obtained here can be used as reasonably accurate preliminary guidelines for optimization of refrigeration and heat pump systems

Oscillating heat pipes

CERN Document Server

Ma, Hongbin

2015-01-01

This book presents the fundamental fluid flow and heat transfer principles occurring in oscillating heat pipes and also provides updated developments and recent innovations in research and applications of heat pipes. Starting with fundamental presentation of heat pipes, the focus is on oscillating motions and its heat transfer enhancement in a two-phase heat transfer system. The book covers thermodynamic analysis, interfacial phenomenon, thin film evaporation,  theoretical models of oscillating motion and heat transfer of single phase and two-phase flows, primary  factors affecting oscillating motions and heat transfer,  neutron imaging study of oscillating motions in an oscillating heat pipes, and nanofluid’s effect on the heat transfer performance in oscillating heat pipes.  The importance of thermally-excited oscillating motion combined with phase change heat transfer to a wide variety of applications is emphasized. This book is an essential resource and learning tool for senior undergraduate, gradua...

Heat pump heating with heat pumps driven by combustion engines or turbines

Energy Technology Data Exchange (ETDEWEB)

Hein, K

1977-01-27

The heat pump described is driven by a gas Otto cycle engine, or a gas- or light- or heavy-oil fired Diesel engine. The claim refers to the use of waste heat of the engines by feeding into the input circuit of the heat pump. In addition, a drive by an electrical motor-generator or power production can be selected at times of peak load in the electrical supply network.

Heat pump technology

CERN Document Server

Von Cube, Hans Ludwig; Goodall, E G A

2013-01-01

Heat Pump Technology discusses the history, underlying concepts, usage, and advancements in the use of heat pumps. The book covers topics such as the applications and types of heat pumps; thermodynamic principles involved in heat pumps such as internal energy, enthalpy, and exergy; and natural heat sources and energy storage. Also discussed are topics such as the importance of the heat pump in the energy industry; heat pump designs and systems; the development of heat pumps over time; and examples of practical everyday uses of heat pumps. The text is recommended for those who would like to kno

Heat transfer entropy resistance for the analyses of two-stream heat exchangers and two-stream heat exchanger networks

International Nuclear Information System (INIS)

Cheng, XueTao; Liang, XinGang

2013-01-01

The entropy generation minimization method is often used to analyze heat transfer processes from the thermodynamic viewpoint. In this paper, we analyze common heat transfer processes with the concept of entropy generation, and propose the concept of heat transfer entropy resistance. It is found that smaller heat transfer entropy resistance leads to smaller equivalent thermodynamic force difference with prescribed heat transfer rate and larger heat transfer rate with prescribed equivalent thermodynamic force difference. With the concept of heat transfer entropy resistance, the performance of two-stream heat exchangers (THEs) and two-stream heat exchanger networks (THENs) is analyzed. For the cases discussed in this paper, it is found that smaller heat transfer entropy resistance always leads to better heat transfer performance for THEs and THENs, while smaller values of the entropy generation, entropy generation numbers and revised entropy generation number do not always. -- Highlights: • The concept of entropy resistance is defined. • The minimum entropy resistance principle is developed. • Smaller entropy resistance leads to better heat transfer

Effectiveness of a heat exchanger in a heat pump clothes dryer

Science.gov (United States)

Nasution, A. H.; Sembiring, P. G.; Ambarita, H.

2018-02-01

This paper deals with study on a heat pump clothes dryer coupled with a heat exchanger. The objective is to explore the effects of the heat exchanger on the performance of the heat pump dryer. The heat pump dryer consists of a vapor compression cycle and integrated with a drying room with volume 1 m3. The power of compressor is 800 Watt and the refrigerant of the cycle is R22. The heat exchanger is a flat plate type with dimensions of 400 mm × 400 mm × 400 mm. The results show the present of the heat exchanger increase the performance of the heat pump dryer. In the present experiment the COP, TP and SMER increase 15.11%, 4.81% and 58.62%, respectively. This is because the heat exchanger provides a better drying condition in the drying room with higher temperature and lower relative humidity in comparison with heat pump dryer without heat exchanger. The effectiveness of the heat exchanger is also high, it is above 50%. It is suggested to install a heat exchanger in a heat pump dryer.

Heat transfer enhancement

International Nuclear Information System (INIS)

Hasatani, Masanobu; Itaya, Yoshinori

1985-01-01

In order to develop energy-saving techniques and new energy techniques, and also most advanced techniques by making industrial equipment with high performance, heat transfer performance frequently becomes an important problem. In addition, the improvement of conventional heat transfer techniques and the device of new heat transfer techniques are often required. It is most proper that chemical engineers engage in the research and development for enhancing heat transfer. The research and development for enhancing heat transfer are important to heighten heat exchange efficiency or to cool equipment for preventing overheat in high temperature heat transfer system. In this paper, the techniques of enhancing radiative heat transfer and the improvement of radiative heat transfer characteristics are reported. Radiative heat transfer is proportional to fourth power of absolute temperature, and it does not require any heat transfer medium, but efficient heat-radiation converters are necessary. As the techniques of enhancing radiative heat transfer, the increase of emission and absorption areas, the installation of emissive structures and the improvement of radiative characteristics are discussed. (Kako, I.)

Heat transfer from internally heated hemispherical pools

International Nuclear Information System (INIS)

Gabor, J.D.; Ellsion, P.G.; Cassulo, J.C.

1980-01-01

Experiments were conducted on heat transfer from internally heated ZnSO 4 -H 2 O pools to the walls of hemispherical containers. This experimental technique provides data for a heat transfer system that has to date been only theoretically treated. Three different sizes of copper hemispherical containers were used: 240, 280, 320 mm in diameter. The pool container served both as a heat transfer surface and as an electrode. The opposing electrode was a copper disk, 50 mm in diameter located at the top of the pool in the center. The top surface of the pool was open to the atmosphere

Heat transfer characteristics of a helical heat exchanger

International Nuclear Information System (INIS)

San, Jung-Yang; Hsu, Chih-Hsiang; Chen, Shih-Hao

2012-01-01

Heat transfer performance of a helical heat exchanger was investigated. The heat exchanger is composed of a helical tube with rectangular cross section and two cover plates. The ε–Ntu relation of the heat exchanger was obtained using a numerical method. In the analysis, the flow in the tube (helical flow) was considered to be mixed and the flow outside the tube (radial flow) was unmixed. In the experiment, the Darcy friction factor (f) and convective heat transfer coefficient (h) of the radial flow were measured. The radial flow was air and the helical flow was water. Four different channel spacing (0.5, 0.8, 1.2 and 1.6 mm) were individually considered. The Reynolds numbers were in the range 307–2547. Two correlations, one for the Darcy friction factor and the other for the Nusselt number, were proposed. - Highlights: ► We analyze the heat transfer characteristics of a helical heat exchanger and examine the effectiveness–Ntu relation. ► Increasing number of turns of the heat exchanger would slightly increase the effectiveness. ► There is an optimum Ntu value corresponding to a maximum effectiveness. ► We measure the Darcy friction factor and Nusselt number of the radial flow and examine the correlations.

Design heating test section HeaTiNG-02

International Nuclear Information System (INIS)

Riswan Djambiar; Sagino; Dedy Haryanto; Joko Prasetio Witoko

2013-01-01

HeaTiNG-02 is a component test loop BETA which serves as a heater in conducting experimental heat transfer processes in two-phase flow in narrow slit-shaped plate, considering this phenomenon is one of the conditions postulated accident scenarios a NPP type PWR. To produce heat for the heating component takes the AC power the source voltage can be set from 0 Volts to 220 Volts with no more than a maximum power of 25 KVA. To obtain the thermal conditions on HeaTiNG-02 heating wire dimensions need to be determined and the corresponding voltage so that it will an expected power. Determination of the dimensions of the heater wire through calculations using electricity formulations. Retrieved draft heater test BETA (UUB) HeaTiNG-02 use material super kanthal (FeCuAl) in diameter (Ø) = 2 mm and wire length 3770 mm. Voltage regulators with a maximum power of 25 kVA with a minimum voltage of 0 volts and a maximum of 220 volts. Heater is used as the base to form refractory stone trench. (author)

Fiscal 1993 investigational report on heat pump heat storage technology; 1993 nendo heat pump chikunetsu gijutsu ni kansuru chosa hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-03-01

This project is for an investigation into the heat pump (HP) use heat storage technology, with the aim of clarifying the present status of HP heat storage technology, the utilization status, and the developmental trend of technology and of contributing to the spread of heat energy effective use using HP heat storage technology and to the promotion of the technical development. Accordingly, the evaluation of the following was made: sensible heat (SH), latent heat (LH), chemical heat storage technology (CH), and heat storage technology (HS). Investigations were made on the sensible heat use heat storage technology of water, brine, stone, soil, etc. in terms of SH; the phase change sensible heat use heat storage technology of ice, hydrate salt, paraffins, etc. in terms of LH; hydration, hydroxide, 2-propanol pyrolysis, adsorption of silica gel, zeolite and water, and heat storage technology using metal hydride, etc. in terms of CH. In terms of HS, the following were studied and evaluated from the study results of the heat storage system in which HP is applied to the sensible heat and latent heat type heat storage technology: contribution to the power load levelling and the reduction of heat source capacity, heat recovery and the use of unused energy, improvement of the system efficiency by combining HP and heat storage technology. 24 refs., 242 figs., 56 tabs.

Heat Roadmap Europe

DEFF Research Database (Denmark)

Connolly, David; Mathiesen, Brian Vad; Lund, Henrik

2015-01-01

This document is a summary of the key technical inputs for the modelling of the heat strategy for Europe outlined in the latest Heat Roadmap Europe studies [1, 2]. These studies quantify the impact of alternative heating strategies for Europe in 2030 and 2050. The study is based on geographical...... information systems (GIS) and energy system analyses. In this report, the inputs for other modelling tools such as PRIMES are presented, in order to enable other researches to generate similar heating scenarios for Europe. Although Heat Roadmap Europe presents a complete heat strategy for Europe, which...... includes energy efficiency, individual heating units (such as boilers and heat pumps), and heat networks, the recommendations here are primarily relating to the potential and modelling of district heating. Although other solutions will play a significant role in decarbonising the heating and cooling sector...

Heat Roadmap Europe

DEFF Research Database (Denmark)

Hansen, Kenneth; Connolly, David; Lund, Henrik

2015-01-01

The cost of heat savings in buildings increase as more heat savings are achieved due to the state of the building stock and hence, alternatives other than savings typically become more economically feasible at a certain level of heat reductions. It is important to identify when the cost of heat...... savings become more expensive than the cost of sustainable heat supply, so society does not overinvest in heat saving measures. This study first investigates the heat saving potentials for different countries in Europe, along with their associated costs, followed by a comparison with alternative ways...... of supplying sustainable heating. Different heat production options are included in terms of individual and community heating systems. Furthermore, the levelised cost of supplying sustainable heat is estimated for both a single technology and from an energy system perspective. The results are analysed...

Impact of Seasonal Heat Accumulation on Operation of Geothermal Heat Pump System with Vertical Ground Heat Exchanger

Science.gov (United States)

Timofeev, D. V.; Malyavina, E. G.

2017-11-01

The subject of the investigation was to find out the influence of heat pump operation in summer on its function in winter. For this purpose a mathematical model of a ground coupled heat pump system has been developed and programmed. The mathematical model of a system ground heat exchanger uses the finite difference method to describe the heat transfer in soil and the analytical method to specify the heat transfer in the U-tubes heat exchanger. The thermal diffusivity by the heat transfer in the soil changes during gradual freezing of the pore moisture and thus slows soil freezing. The mathematical model of a heat pump includes the description of a scroll compressor and the simplified descriptions of the evaporator and condenser. The analysis showed that heating during the cold season and cooling in the warm season affect the average heat transfer medium temperature in the soil loop in the winter season. It has been also showed that the degree of this effect depends on the clay content in the soil.

Profitability of heating entrepreneurship from the viewpoint of heating energy buyer, heating energy seller and energy wood seller

Energy Technology Data Exchange (ETDEWEB)

Sauvula-Seppaelae, T.; Ulander, E. (Seinaejoki Univ. of Applied Sciences, Ahtari (Finland), School of Agriculture and Forestry), e-mail: tiina.sauvula-seppala@seamk.fi, e-mail: essi.ulander@seamk.fi

2010-07-01

The focus of this research was to study the profitability of heating entrepreneurships from the viewpoint of heating energy buyer, seller as well as energy wood seller. The average costs of heat production were Eur 44,8 / MWh and incomes Eur 43,4 /MWh. Energy wood purchase, comminution and long distance transportation formed slightly over a half of the heat production costs. Average net income in the group of the largest heating plants (>1000 kW) was Eur 29000 per year and in the group of the smallest (<200 kW) average net income was slightly over Eur 4000 per year. The net income from selling heat represents only a part of the income a heating entrepreneur receives from heat production. Other, significant parts are formed by income from selling energy wood to the plant as well as compensation for supervision and maintenance of the plant. The average net income of a forest owner from selling energy wood to heating entrepreneurs was Eur 18 / m3. Without state subsidies the net income would have been Eur 4 / m3. The price of the heating energy sold by heating entrepreneurs was very competitive. In 2006 it was Eur 30 / MWh cheaper than oil heat, Eur 34 / MWh cheaper than electric heat and Eur 3 / MWh cheaper than district heating. (orig.)

volBrain: An Online MRI Brain Volumetry System

Science.gov (United States)

Manjón, José V.; Coupé, Pierrick

2016-01-01

The amount of medical image data produced in clinical and research settings is rapidly growing resulting in vast amount of data to analyze. Automatic and reliable quantitative analysis tools, including segmentation, allow to analyze brain development and to understand specific patterns of many neurological diseases. This field has recently experienced many advances with successful techniques based on non-linear warping and label fusion. In this work we present a novel and fully automatic pipeline for volumetric brain analysis based on multi-atlas label fusion technology that is able to provide accurate volumetric information at different levels of detail in a short time. This method is available through the volBrain online web interface (http://volbrain.upv.es), which is publically and freely accessible to the scientific community. Our new framework has been compared with current state-of-the-art methods showing very competitive results. PMID:27512372

volBrain: an online MRI brain volumetry system

Directory of Open Access Journals (Sweden)

Jose V. Manjon

2016-07-01

Full Text Available The amount of medical image data produced in clinical and research settings is rapidly growing resulting in vast amount of data to analyze. Automatic and reliable quantitative analysis tools, including segmentation, allow to analyze brain development and to understand specific patterns of many neurological diseases. This field has recently experienced many advances with successful techniques based on non-linear warping and label fusion. In this work we present a novel and fully automatic pipeline for volumetric brain analysis based on multi-atlas label fusion technology that is able to provide accurate volumetric information at different levels of detail in a short time. This method is available through the volBrain online web interface (http://volbrain.upv.es, which is publically and freely accessible to the scientific community. Our new framework has been compared with current state-of-the-art methods showing very competitive results.

volBrain: An Online MRI Brain Volumetry System.

Science.gov (United States)

Manjón, José V; Coupé, Pierrick

2016-01-01

The amount of medical image data produced in clinical and research settings is rapidly growing resulting in vast amount of data to analyze. Automatic and reliable quantitative analysis tools, including segmentation, allow to analyze brain development and to understand specific patterns of many neurological diseases. This field has recently experienced many advances with successful techniques based on non-linear warping and label fusion. In this work we present a novel and fully automatic pipeline for volumetric brain analysis based on multi-atlas label fusion technology that is able to provide accurate volumetric information at different levels of detail in a short time. This method is available through the volBrain online web interface (http://volbrain.upv.es), which is publically and freely accessible to the scientific community. Our new framework has been compared with current state-of-the-art methods showing very competitive results.

Cryogenic heat transfer

CERN Document Server

Barron, Randall F

2016-01-01

Cryogenic Heat Transfer, Second Edition continues to address specific heat transfer problems that occur in the cryogenic temperature range where there are distinct differences from conventional heat transfer problems. This updated version examines the use of computer-aided design in cryogenic engineering and emphasizes commonly used computer programs to address modern cryogenic heat transfer problems. It introduces additional topics in cryogenic heat transfer that include latent heat expressions; lumped-capacity transient heat transfer; thermal stresses; Laplace transform solutions; oscillating flow heat transfer, and computer-aided heat exchanger design. It also includes new examples and homework problems throughout the book, and provides ample references for further study.

Nonazeotropic Heat Pump

Science.gov (United States)

Ealker, David H.; Deming, Glenn

1991-01-01

Heat pump collects heat from water circulating in heat-rejection loop, raises temperature of collected heat, and transfers collected heat to water in separate pipe. Includes sealed motor/compressor with cooling coils, evaporator, and condenser, all mounted in outer housing. Gradients of temperature in evaporator and condenser increase heat-transfer efficiency of vapor-compression cycle. Intended to recover relatively-low-temperature waste heat and use it to make hot water.

Heat pumps

CERN Document Server

Macmichael, DBA

1988-01-01

A fully revised and extended account of the design, manufacture and use of heat pumps in both industrial and domestic applications. Topics covered include a detailed description of the various heat pump cycles, the components of a heat pump system - drive, compressor, heat exchangers etc., and the more practical considerations to be taken into account in their selection.

Integrated multiscale simulation of combined heat and power based district heating system

International Nuclear Information System (INIS)

Li, Peifeng; Nord, Natasa; Ertesvåg, Ivar Ståle; Ge, Zhihua; Yang, Zhiping; Yang, Yongping

2015-01-01

Highlights: • Simulation of power plant, district heating network and heat users in detail and integrated. • Coupled calculation and analysis of the heat and pressure losses of the district heating network. • District heating is not preferable for very low heat load due to relatively high heat loss. • Lower design supply temperatures of the district heating network give higher system efficiency. - Abstract: Many studies have been carried out separately on combined heat and power and district heating. However, little work has been done considering the heat source, the district heating network and the heat users simultaneously, especially when it comes to the heating system with large-scale combined heat and power plant. For the purpose of energy conservation, it is very important to know well the system performance of the integrated heating system from the very primary fuel input to the terminal heat users. This paper set up a model of 300 MW electric power rated air-cooled combined heat and power plant using Ebsilon software, which was validated according to the design data from the turbine manufacturer. Then, the model of heating network and heat users were developed based on the fundamental theories of fluid mechanics and heat transfer. Finally the combined heat and power based district heating system was obtained and the system performances within multiscale scope of the system were analyzed using the developed Ebsilon model. Topics with regard to the heat loss, the pressure drop, the pump power consumption and the supply temperatures of the district heating network were discussed. Besides, the operational issues of the integrated system were also researched. Several useful conclusions were drawn. It was found that a lower design primary supply temperature of the district heating network would give a higher seasonal energy efficiency of the integrated system throughout the whole heating season. Moreover, it was not always right to relate low design

Heat Roadmap Europe

DEFF Research Database (Denmark)

Connolly, David; Lund, Henrik; Mathiesen, Brian Vad

2014-01-01

compared to 1990 levels. None of these scenarios involve the large-scale implementation of district heating, but instead they focus on the electrification of the heating sector (primarily using heat pumps) and/or the large-scale implementation of electricity and heat savings. In this paper, the potential...... for district heating in the EU between now and 2050 is identified, based on extensive and detailed mapping of the EU heat demand and various supply options. Subsequently, a new ‘district heating plus heat savings’ scenario is technically and economically assessed from an energy systems perspective. The results...... indicate that with district heating, the EU energy system will be able to achieve the same reductions in primary energy supply and carbon dioxide emissions as the existing alternatives proposed. However, with district heating these goals can be achieved at a lower cost, with heating and cooling costs...

The study of the heat-engineering characteristics of a solar heat collector based on aluminum heat pipes

International Nuclear Information System (INIS)

Khairnasov, S.M.; Zaripov, V.K.; Passamakin, B.M. et al.

2013-01-01

This paper presents the results of studies into the heat-engineering characteristics of a flat heat solar collector based on aluminum heat pipes that is designed to be used in building facades. The principle of work and the structure of the solar collector are considered; the results of its comparison with a traditional flat solar collector are presented. The studies were performed at a heat carrier temperature range of +10 - +30 degree C and at a solar heat flow density of 400 - 1000 W/m 2 . The obtained experimental heat-engineering characteristics of the collector based on heat pipes show that they are at a level of traditional flow solar collectors; for example, its efficiency is 0.65 - 0.73. Meanwhile, the hydraulic resistance of the structure with heat pipes is by a factor of 2 - 2.4 smaller and ensures a high level of scalability, reliability, and maintainability, which is important when using it as an element of facade constructions of solar heat systems. (author)

Heat transfer characteristics of a direct contact heat exchanger

International Nuclear Information System (INIS)

Kinoshita, I.; Nishi, Y.

1993-01-01

As a first step for development of a direct contact steam generator for FBRs, fundamental heat transfer characteristics of a liquid-liquid contact heat exchanger were evaluated by heat transfer experiment with low melting point alloy and water. Distinctive characteristics of direct contact heat transfer with liquid metal and water was obtained. (author)

Performance analysis of diesel engine heat pump incorporated with heat recovery

International Nuclear Information System (INIS)

Shah, N.N.; Huang, M.J.; Hewitt, N.J.

2016-01-01

Highlights: • Diesel engine heat pump with heat recovery. • Water-to-water source heat pump based on R134a. • Possibility for different flow temperature for heat distribution system. • Possible retrofit application in off-gas or weak electricity network area. • Potential to diversify use of fossil fuel, primary energy and CO_2 emission savings. - Abstract: This paper presents experimental study of diesel engine heat pump (DEHP) system to find potential as retrofit technology in off-gas or weak electricity network area to replace existing gas/oil/electric heating system in domestic sector. Test set-up of diesel engine driven water-to-water heat pump system was built which included heat recovery arrangement from the engine coolant & exhaust gas. The system was designed to meet typical house heating demand in Northern Ireland. Performance of DEHP was evaluated to meet house-heating demand at different flow temperature (35, 45, 55 & 65 °C), a typical requirement of underfloor space heating, medium/high temperature radiators and domestic hot water. The performance was evaluated against four-evaporator water inlet temperature (0, 5, 10 & 15 °C) and at three different engine speed 1600, 2000 & 2400 rpm. Experiment results were analysed in terms of heating/cooling capacity, heat recovery, total heat output, primary energy ratio (PER), isentropic efficiency, etc. Test results showed that DEHP is able to meet house-heating demand with help of heat recovery with reduced system size. Heat recovery contributed in a range of 22–39% in total heat output. It is possible to achieve high flow temperature in a range of 74 °C with help of heat recovery. Overall system PER varied in a range of 0.93–1.33. Speed increment and flow temperature has significant impact on heat recovery, total heat output and PER. A case scenario with different flow temperature to match house-heating demand has been presented to show working potential with different heat distribution system

Browse Title Index

African Journals Online (AJOL)

Items 7351 - 7400 of 11090 ... Vol 10, No 65 (2011), Molecular cloning and sequence analysis of VP6 gene of giant panda rotavirus strain CH-1, Abstract PDF. Y Lie, S Chen, CD Wang, Z Zhang, CD Wang, W Guo, X Wang, L Guo, Q Yan. Vol 11, No 23 (2012), Molecular cloning, characterization and expression analysis of heat ...

Application of heat pipes in nuclear reactors for passive heat removal

Energy Technology Data Exchange (ETDEWEB)

Haque, Z.; Yetisir, M., E-mail: haquez@aecl.ca [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

2013-07-01

This paper introduces a number of potential heat pipe applications in passive (i.e., not requiring external power) nuclear reactor heat removal. Heat pipes are particularly suitable for small reactors as the demand for heat removal is significantly less than commercial nuclear power plants, and passive and reliable heat removal is required. The use of heat pipes has been proposed in many small reactor designs for passive heat removal from the reactor core. This paper presents the application of heat pipes in AECL's Nuclear Battery design, a small reactor concept developed by AECL. Other potential applications of heat pipes include transferring excess heat from containment to the atmosphere by integrating low-temperature heat pipes into the containment building (to ensure long-term cooling following a station blackout), and passively cooling spent fuel bays. (author)

A two-stage heating scheme for heat assisted magnetic recording

Science.gov (United States)

Xiong, Shaomin; Kim, Jeongmin; Wang, Yuan; Zhang, Xiang; Bogy, David

2014-05-01

Heat Assisted Magnetic Recording (HAMR) has been proposed to extend the storage areal density beyond 1 Tb/in.2 for the next generation magnetic storage. A near field transducer (NFT) is widely used in HAMR systems to locally heat the magnetic disk during the writing process. However, much of the laser power is absorbed around the NFT, which causes overheating of the NFT and reduces its reliability. In this work, a two-stage heating scheme is proposed to reduce the thermal load by separating the NFT heating process into two individual heating stages from an optical waveguide and a NFT, respectively. As the first stage, the optical waveguide is placed in front of the NFT and delivers part of laser energy directly onto the disk surface to heat it up to a peak temperature somewhat lower than the Curie temperature of the magnetic material. Then, the NFT works as the second heating stage to heat a smaller area inside the waveguide heated area further to reach the Curie point. The energy applied to the NFT in the second heating stage is reduced compared with a typical single stage NFT heating system. With this reduced thermal load to the NFT by the two-stage heating scheme, the lifetime of the NFT can be extended orders longer under the cyclic load condition.

German central solar heating plants with seasonal heat storage

Energy Technology Data Exchange (ETDEWEB)

Bauer, D.; Marx, R.; Nussbicker-Lux, J.; Ochs, F.; Heidemann, W. [Institute of Thermodynamics and Thermal Engineering (ITW), University of Stuttgart, Pfaffenwaldring 6, D-70550 Stuttgart (Germany); Mueller-Steinhagen, H. [Institute of Thermodynamics and Thermal Engineering (ITW), University of Stuttgart, Pfaffenwaldring 6, D-70550 Stuttgart (Germany); Institute of Technical Thermodynamics (ITT), German Aerospace Centre (DLR), Stuttgart (Germany)

2010-04-15

Central solar heating plants contribute to the reduction of CO{sub 2}-emissions and global warming. The combination of central solar heating plants with seasonal heat storage enables high solar fractions of 50% and more. Several pilot central solar heating plants with seasonal heat storage (CSHPSS) built in Germany since 1996 have proven the appropriate operation of these systems and confirmed the high solar fractions. Four different types of seasonal thermal energy stores have been developed, tested and monitored under realistic operation conditions: Hot-water thermal energy store (e.g. in Friedrichshafen), gravel-water thermal energy store (e.g. in Steinfurt-Borghorst), borehole thermal energy store (in Neckarsulm) and aquifer thermal energy store (in Rostock). In this paper, measured heat balances of several German CSHPSS are presented. The different types of thermal energy stores and the affiliated central solar heating plants and district heating systems are described. Their operational characteristics are compared using measured data gained from an extensive monitoring program. Thus long-term operational experiences such as the influence of net return temperatures are shown. (author)

Heat pipes and use of heat pipes in furnace exhaust

Science.gov (United States)

Polcyn, Adam D.

2010-12-28

An array of a plurality of heat pipe are mounted in spaced relationship to one another with the hot end of the heat pipes in a heated environment, e.g. the exhaust flue of a furnace, and the cold end outside the furnace. Heat conversion equipment is connected to the cold end of the heat pipes.

Estimating heat-to-heat variation from a statistician's point of view

International Nuclear Information System (INIS)

Hebble, T.L.

1976-01-01

Heat-to-heat variability is the change in results that occurs when the same tests under the same conditions are applied to samples from different heats of the same material. Heat-to-heat variability reflects, among other things, difference in chemistry and in processing history. Published Japanese tensile and creep tests on types 304 and 316 stainless steel tube are used to illustrate the analysis of variance technique as a tool for isolating heat-to-heat variation. The importance of the underlying model and the role of replication are indicated. Finally, confidence intervals and tolerance limits are computed from numerical estimates of heat-to-heat variation. 17 tables

Heat Roadmap Europe

DEFF Research Database (Denmark)

David, Andrei; Mathiesen, Brian Vad; Averfalk, Helge

2017-01-01

The Heat Roadmap Europe (HRE) studies estimated a potential increase of the district heating (DH) share to 50% of the entire heat demand by 2050, with approximately 25–30% of it being supplied using large-scale electric heat pumps. This study builds on this potential and aims to document that suc......The Heat Roadmap Europe (HRE) studies estimated a potential increase of the district heating (DH) share to 50% of the entire heat demand by 2050, with approximately 25–30% of it being supplied using large-scale electric heat pumps. This study builds on this potential and aims to document...

The contact heat transfer between the heating plate and granular materials in rotary heat exchanger under overloaded condition

Directory of Open Access Journals (Sweden)

Luanfang Duan

2018-03-01

Full Text Available In the present work, the contact heat transfer between the granular materials and heating plates inside plate rotary heat exchanger (PRHE was investigated. The heat transfer coefficient is dominated by the contact heat transfer coefficient at hot wall surface of the heating plates and the heat penetration inside the solid bed. A plot scale PRHE with a diameter of Do = 273 mm and a length of L = 1000 mm has been established. Quartz sand with dp = 2 mm was employed as the experimental material. The operational parameters were in the range of ω = 1 – 8 rpm, and F = 15, 20, 25, 30%, and the effect of these parameters on the time-average contact heat transfer coefficient was analyzed. The time-average contact heat transfer coefficient increases with the increase of rotary speed, but decreases with the increase of the filling degree. The measured data of time-average heat transfer coefficients were compared with theoretical calculations from Schlünder’s model, a good agreement between the measurements and the model could be achieved, especially at a lower rotary speed and filling degree level. The maximum deviation between the calculated data and the experimental data is approximate 10%. Keywords: Rotary heat exchanger, Contact heat transfer, Granular material, Heating plate, Overloaded

Heat-Related Illnesses

Science.gov (United States)

... Share this! EmergencyCareForYou » Emergency 101 » Heat-Related Illnesses Heat-Related Illnesses Dr. Glenn Mitchell , Emergency physician at ... about heat cramps and heat stroke and exhaustion. Heat Cramps Symptoms include muscle spasms, usually in the ...

Heat savings in buildings in a 100% renewable heat and power system in Denmark with different shares of district heating

DEFF Research Database (Denmark)

Zvingilaite, Erika; Balyk, Olexandr

2014-01-01

levels of heat savings, which can be implemented by reducing heat transmission losses through building elements and by installing ventilation systems with heat recovery, in different future Danish heat and power system scenarios. Today almost 50% of heat demand in Denmark is covered by district heating......The paper examines implementation of heat saving measures in buildings in 2050, under the assumption that heat and power supply comes solely from renewable resources in Denmark.Balmorel – a linear optimisation model of heat and power sectors in Denmark is used for investigating economically viable....... A further expansion of district heating network in Denmark is assessed and penetration of heat savings is analysed in this context.If all heat saving measures, included in the model, are implemented, heat demand in Danish buildings in 2050 could be reduced by around 40%. Results show that it is cost...

Plasma heating

International Nuclear Information System (INIS)

Wilhelm, R.

1989-01-01

Successful plasma heating is essential in present fusion experiments, for the demonstration of DpT burn in future devices and finally for the fusion reactor itself. This paper discusses the common heating systems with respect to their present performance and their applicability to future fusion devices. The comparative discussion is oriented to the various function of heating, which are: - plasma heating to fusion-relevant parameters and to ignition in future machines, -non-inductive, steady-pstate current drive, - plasma profile control, -neutral gas breakdown and plasma build-up. In view of these different functions, the potential of neutral beam injection (NBI) and the various schemes of wave heating (ECRH, LH, ICRH and Alven wave heating) is analyzed in more detail. The analysis includes assessments of the present physical and technical state of these heating methods, and makes suggestions for future developments and about outstanding problems. Specific attention is given to the still critical problem of efficient current drive, especially with respect to further extrapolation towards an economically operating tokamak reactor. Remarks on issues such as reliability, maintenance and economy conclude this comparative overview on plasma heating systems. (author). 43 refs.; 13 figs.; 3 tabs

Compact seasonal PCM heat storage for solar heating systems

DEFF Research Database (Denmark)

Dannemand, Mark

Space heating of buildings and preparation of domestic hot water accounts for a large part of the society’s energy consumption. Solar radiation is an abundant and renewable energy source which can be harvested by solar collectors and used to cover heating demands in the built environment....... The seasonal availability of solar energy does however not match with the heating demands in buildings which typically are large in winter periods when limited solar energy is available. Heat can be stored over a few days in water stores but continuous heat losses limits the storage periods. The possibility...... of storing heat from summer where solar energy is widely available to winter periods where the heating demands are large, allows for implementing more renewable energy in our energy system. The phase change material (PCM) sodium acetate trihydrate (SAT) melts at 58 °C. The melting process requires...

Heat transfer from internally-heated molten UO2 pools

International Nuclear Information System (INIS)

Stein, R.P.; Baker, L. Jr.; Gunther, W.H.; Cook, C.

1978-01-01

Experimental measurements of heat transfer from internally heated pools of molten UO 2 have been obtained for two cell sizes: 10 cm x 10 cm and 20 cm x 20 cm. The experiments with the large cell have supported a previous conclusion from early small data that the measured downward heat fluxes are higher than would be expected on the basis of considerations of thermal convection. A convective model underpredicts the downward heat fluxes by a factor of 2.5 to 4.5 for all but one early experiment. Arbitrary assumptions of increased thermal conductivity do not account for the discrepancy. A single model based on internal thermal radiation heat transfer is able to account for the high values. The model uses the optically thick Rosseland approximation. Because of this, it is tentatively concluded that thermal radiation plays a dominant role in controlling the heat transfer from internally heated molted fuel

Environmental and energy efficiency evaluation of residential gas and heat pump heating

International Nuclear Information System (INIS)

Ganji, A.R.

1993-01-01

Energy efficiency and source air pollutant emission factors of gas heaters, gas engine heat pumps, and electric heat pumps for domestic heating have been evaluated and compared. The analysis shows that with the present state of technology, gas engine heat pumps have the highest energy efficiency followed by electric heat pumps and then gas heaters. Electric heat pumps produce more than twice as much NO x , and comparable CO 2 and CO per unit of useful heating energy compared to natural gas heaters. CO production per unit of useful heating energy from gas engine heat pumps without any emission control is substantially higher than electric heat pumps and natural gas heaters. NO x production per unit of useful heating energy from natural gas engine heat pumps (using lean burn technology) without any emission control is about the same as effective NO x production from electric heat pumps. Gas engine heat pumps produce about one-half CO 2 compared to electric heat pumps

Research of the heat exchanging processes running in the heating and hot water supply loops of the coil heat exchangers

Directory of Open Access Journals (Sweden)

Ірина Геннадіївна Шитікова

2016-11-01

Full Text Available The fuel-energy complex research has made it possible to disclose a huge power-saving potential in the municipal heat-and-power engineering. Power-and-resource-saving units and systems are becoming extremely urgent because of the power engineering crisis expansion. The self-adjusting heat supply system from the individual heating points with the heat-accumulating units and coil heat exchangers for independent heating and water supply systems has been examined. Coil heat exchangers are used in municipal heating for heat transfer (e.g. geothermal waters for the independent mains of the heating and hot water supply systems. The heat engineering calculation of the heating and accumulating unit with the coil heat exchanger for independent heat supply systems from individual heater was performed and experimental data were received at the experimental industrial unit under the laboratory conditions. The peculiarities of the flows in the intertubular space, their influence on the heat exchange and temperatures of the first and intermediate mains have been shown. It is important to know the processes running inside the apparatus to be able to improve the technical characteristics of the three-loop coil heat exchanger. The task solution will make it possible to save the materials consumption for the three-loop coil heat exchangers in the future

Heat-Related Illnesses

Medline Plus

Full Text Available ... Share this! EmergencyCareForYou » Emergency 101 » Heat-Related Illnesses Heat-Related Illnesses Dr. Glenn Mitchell , Emergency physician at ... about heat cramps and heat stroke and exhaustion. Heat Cramps Symptoms include muscle spasms, usually in the ...

Heat Stress

Science.gov (United States)

... Publications and Products Programs Contact NIOSH NIOSH HEAT STRESS Recommend on Facebook Tweet Share Compartir OSHA-NIOSH ... hot environments may be at risk of heat stress. Exposure to extreme heat can result in occupational ...

Local heat transfer where heated rods touch in axially flowing water

International Nuclear Information System (INIS)

Kast, S.J.

1983-05-01

An anlaytic model is developed to predict the azimuthal width of a stablesteam blanket region near the line of contact between two heated rods cooled by axially flowing water at high pressure. The model is intended to aid analysis of reduced surface heat transfer capability for the abnormal configuration of nuclear fuel rods bowed into contact in the core of a pressurized water nuclear reactor. The analytic model predicts the azimuthal width of the steam blanket zone having reduced surface heat transfer as a function of rod average heat flux, subchannel coolant conditions and rod dimensions. The analytic model is developed from a heat balance between the heat generated in the wall of a heated empty tube and the heat transported away by transverse mixing and axial convection in the coolant subchannel. The model is developed for seveal geometries including heated rods in line contact, a heated rod touching a short insulating plane and a heated rod touching the inside of a metal guide tube

Experimental investigation on Heat Transfer Performance of Annular Flow Path Heat Pipe

International Nuclear Information System (INIS)

Kim, In Guk; Kim, Kyung Mo; Jeong, Yeong Shin; Bang, In Cheol

2015-01-01

Mochizuki et al. was suggested the passive cooling system to spent nuclear fuel pool. Detail analysis of various heat pipe design cases was studied to determine the heat pipes cooling performance. Wang et al. suggested the concept PRHRS of MSR using sodium heat pipes, and the transient performance of high temperature sodium heat pipe was numerically simulated in the case of MSR accident. The meltdown at the Fukushima Daiichi nuclear power plants alarmed to the dangers of station blackout (SBO) accident. After the SBO accident, passive decay heat removal systems have been investigated to prevent the severe accidents. Mochizuki et al. suggested the heat pipes cooling system using loop heat pipes for decay heat removal cooling and analysis of heat pipe thermal resistance for boiling water reactor (BWR). The decay heat removal systems for pressurized water reactor (PWR) were suggested using natural convection mechanisms and modification of PWR design. Our group suggested the concept of a hybrid heat pipe with control rod as Passive IN-core Cooling System (PINCs) for decay heat removal for advanced nuclear power plant. Hybrid heat pipe is the combination of the heat pipe and control rod. In the present research, the main objective is to investigate the effect of the inner structure to the heat transfer performance of heat pipe containing neutron absorber material, B 4 C. The main objective is to investigate the effect of the inner structure in heat pipe to the heat transfer performance with annular flow path. ABS pellet was used instead of B 4 C pellet as cylindrical structures. The thermal performances of each heat pipes were measured experimentally. Among them, concentric heat pipe showed the best performance compared with others. 1. Annular evaporation section heat pipe and annular flow path heat pipe showed heat transfer degradation. 2. AHP also had annular vapor space and contact cooling surface per unit volume of vapor was increased. Heat transfer coefficient of

HEAT PUMP USING SUBSOIL WATERS AS LOW TEMPERATURE HEAT SOURCE

Directory of Open Access Journals (Sweden)

Denysova Alla

2015-08-01

Full Text Available One of the basic directions of perfection of heat supply systems is the tendency of transition to the low-temperature heating systems based on application of heat pump installations. We consider heat supply system with heat pump installations using subsoil waters. Numerical simulation of thermal processes in the elements of a single-stage and double-stage heat pump systems has been worked out. Values of depths of wells and their quantity, necessary for effective operation of the offered installations, and values of capacity of electric water pumps for subsoil waters unit are calculated. Capacity of compressor electric drive and coefficient of performance of heat pump for the conditions of the city of Odessa are presented.

Conjugate heat and mass transfer in heat mass exchanger ducts

CERN Document Server

Zhang, Li-Zhi

2013-01-01

Conjugate Heat and Mass Transfer in Heat Mass Exchanger Ducts bridges the gap between fundamentals and recent discoveries, making it a valuable tool for anyone looking to expand their knowledge of heat exchangers. The first book on the market to cover conjugate heat and mass transfer in heat exchangers, author Li-Zhi Zhang goes beyond the basics to cover recent advancements in equipment for energy use and environmental control (such as heat and moisture recovery ventilators, hollow fiber membrane modules for humidification/dehumidification, membrane modules for air purification, desi

Condensation heat transfer in plate heat exchangers

International Nuclear Information System (INIS)

Panchal, C.B.

1985-01-01

An Alfa-Laval plate heat exchanger, previously tested as an evaporator, was retested as a condenser. Two series of tests with different chevron-angle plates were carried out using ammonia as a working fluid. The overall heat-transfer coefficient and pressure drop were measured, and the effects of operating parameters were determined. The experimental data were compared with theoretical predictions. In the analysis, a gravity-controlled condensation process was modeled theoretically, and the overall performance was calculated. The analysis shows that the overall heat-transfer coefficient can be predicted with an average uncertainty of about 10%. It is, however, important to consider the interfacial shear stress, because the effective friction factor is high for flow in plate heat exchangers

Heat Transfer in Metal Foam Heat Exchangers at High Temperature

Science.gov (United States)

Hafeez, Pakeeza

Heat transfer though open-cell metal foam is experimentally studied for heat exchanger and heat shield applications at high temperatures (˜750°C). Nickel foam sheets with pore densities of 10 and 40 pores per linear inch (PPI), have been used to make the heat exchangers and heat shields by using thermal spray coating to deposit an Inconel skin on a foam core. Heat transfer measurements were performed on a test rig capable of generating hot gas up to 1000°C. The heat exchangers were tested by exposing their outer surface to combustion gases at a temperature of 550°C and 750°C while being cooled by air flowing through them at room temperature at velocities up to 5 m/s. The temperature rise of the air, the surface temperature of the heat exchangers and the air temperature inside the heat exchanger were measured. The volumetric heat transfer coefficient and Nusselt number were calculated for different velocities. The heat transfer performance of the 40PPI sample brazed with the foil is found to be the most efficient. Pressure drop measurements were also performed for 10 and 40PPI metal foam. Thermographic measurements were done on 40PPI foam heat exchangers using a high temperature infrared camera. A high power electric heater was used to produce hot air at 300°C that passed over the foam heat exchanger while the cooling air was blown through it. Heat shields were made by depositing porous skins on metal foam and it was observed that a small amount of coolant leaking through the pores notably reduces the heat transfer from the hot gases. An analytical model was developed based assuming local thermal non-equilibrium that accounts for the temperature difference between solid and fluid phase. The experimental results are found to be in good agreement with the predicted values of the model.

The Avenging Females: A Comparative Analysis of Kill Bill Vol.1-2, Death Proof and Sympathy for Lady Vengeance

Directory of Open Access Journals (Sweden)

Basak Göksel Demiray

2012-04-01

Full Text Available This paper provides a comparative analysis of Quentin Tarantino’s Kill Bill Vol.1-2 (2003, 2004, Death Proof (2007 and Park Chan Wook’s Sympathy for Lady Vengeance (Chinjeolhan Geumjassi, 2005. The primary objectives of this study are: (1 to reveal the gender-biases inherent to the fundamental discursive structures of the foregoing films; (2 to compare and contrast the films through an analysis of the ‘gaze(s’ and possible ‘pleasures’,  which are inherent in their narratives, in relation to Laura Mulvey’s and Carol Clover’s approaches; and (3 to distinguish Kill Bill Vol.1-2 from the foregoing two and the ‘avenging female’ clichés of the other horror/violence movies in the context of the replaced positionings of its protagonist and antagonist inherent in its distinct narrative style.

Renewable-based heat supply of multi-apartment buildings with varied heat demands

International Nuclear Information System (INIS)

Truong, Nguyen Le; Dodoo, Ambrose; Gustavsson, Leif

2015-01-01

This study investigates the cost and primary energy use to heat an existing multi-apartment building in Sweden, before and after deep energy efficiency renovation, with different types of renewable-based systems. District heating systems of different scales as well as local heat production based on bioelectric boilers, ground-source bioelectric heat pumps and wood pellet boilers with or without solar heating are considered. The annual energy demand of the building, calculated hour by hour, with and without energy efficiency improvements, are matched against the renewable-based heat supply options by techno-economic modeling to minimize cost for each considered heat supply option. The results show that the availability of heating technologies at the building site and the scale of the building's heat demand influence the cost and the primary energy efficiency of the heating options. District heat from large-scale systems is cost efficient for the building without energy-efficiency improvement, whereas electric heat pumps and wood pellet boilers are more cost efficient when implementing energy-efficiency improvement. However, the cost difference is small between these alternatives and sensitive to the size of building. Large-scale district heating with cogeneration of power is most primary energy efficient while heat pumps and medium-scale district heating are nearly as efficient. - Highlights: • Heating technologies influence costs and primary energy use of a building. • Large-scale district heating with cogeneration of power is primary energy efficient. • Large-scale district heating is cost efficient for buildings with large heat demand. • Heat pumps and pellet boilers are cost competitive in energy-efficient buildings.

Heat transfer analysis of underground U-type heat exchanger of ground source heat pump system.

Science.gov (United States)

Pei, Guihong; Zhang, Liyin

2016-01-01

Ground source heat pumps is a building energy conservation technique. The underground buried pipe heat exchanging system of a ground source heat pump (GSHP) is the basis for the normal operation of an entire heat pump system. Computational-fluid-dynamics (CFD) numerical simulation software, ANSYS-FLUENT17.0 have been performed the calculations under the working conditions of a continuous and intermittent operation over 7 days on a GSHP with a single-well, single-U and double-U heat exchanger and the impact of single-U and double-U buried heat pipes on the surrounding rock-soil temperature field and the impact of intermittent operation and continuous operation on the outlet water temperature. The influence on the rock-soil temperature is approximately 13 % higher for the double-U heat exchanger than that of the single-U heat exchanger. The extracted energy of the intermittent operation is 36.44 kw·h higher than that of the continuous mode, although the running time is lower than that of continuous mode, over the course of 7 days. The thermal interference loss and quantity of heat exchanged for unit well depths at steady-state condition of 2.5 De, 3 De, 4 De, 4.5 De, 5 De, 5.5 De and 6 De of sidetube spacing are detailed in this work. The simulation results of seven working conditions are compared. It is recommended that the side-tube spacing of double-U underground pipes shall be greater than or equal to five times of outer diameter (borehole diameter: 180 mm).

Distributed heat generation in a district heating system

OpenAIRE

Lennermo, Gunnar; Lauenberg, Patrick

2016-01-01

District heating (OH) systems need to be improved  regarding integration  of decentralised  heat generation. Micro production, prosumers and smart grids are terms becoming more and more common  in  connection  to  the  power  grid.  Concerning district  heating,  the  development  is slower, although improving. Today there are a number of such decentralised units for heat generation,  mainly  solar,  that have been partly evaluated.  Previous  studies  have shown  that there is a need to deve...

Method and means for heating buildings in a district heating system with waste heat from a thermal power plant

International Nuclear Information System (INIS)

Margen, P.H.E.

1975-01-01

The waste heat from a thermal power plant is transported through a municipal heating network to a plurality of buildings to be heated. The quantity of heat thus supplied to the buildings is higher than that required for the heating of the buildings. The excess heat is released from the buildings to the atmosphere in the form of hot air

News from heat-pump research - Large-scale heat pumps, components, heat pumps and solar heating; News aus der Waermepumpen-Forschung - Gross-Waermepumpen, Komponenten, Waermepumpe und Solar

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-06-15

These proceedings summarise the presentations made at the 16{sup th} annual meeting held by the Swiss Federal Office of Energy's Heat Pump Research Program in Burgdorf, Switzerland. The proceedings include contributions on large-scale heat pumps, components and the activities of the heat pump promotion society. A summary of targets and trends in energy research in general is presented and an overview of the heat pump market in 2009 and future perspectives is given. International work within the framework of the International Energy Agency's heat pump group is reviewed, including solar - heat pump combinations. Field-monitoring and the analysis of large-scale heat pumps are discussed and the importance of the use of correct concepts in such installations is stressed. Large-scale heat pumps with carbon dioxide as working fluid are looked at, as are output-regulated air/water heat pumps. Efficient system solutions with heat pumps used both to heat and to cool are discussed. Deep geothermal probes and the potential offered by geothermal probes using carbon dioxide as a working fluid are discussed. The proceedings are rounded off with a list of useful addresses.

Thermal behavior of a heat exchanger module for seasonal heat storage

DEFF Research Database (Denmark)

Fan, Jianhua; Furbo, Simon; Andersen, Elsa

2012-01-01

Experimental and theoretic investigations are carried out to study the heat transfer capacity rate of a heat exchanger module for seasonal heat storage with sodium acetate trihydrate (SAT) supercooling in a stable way. A sandwich heat storage test module has been built with the phase change...... material (PCM) storage box in between two plate heat exchangers. Charge of the PCM storage is investigated experimentally with solid phase SAT as initial condition. Discharge of the PCM storage with the presence of crystallization is studied experimentally. Fluid flow and heat transfer in the PCM module......, recommendations on how best to transfer heat to and from the seasonal heat storage module are given....

Heat recovery from a cement plant with a Marnoch Heat Engine

International Nuclear Information System (INIS)

Saneipoor, P.; Naterer, G.F.; Dincer, I.

2011-01-01

This paper examines the performance of a new Marnoch Heat Engine (MHE) that recovers waste heat from within a typical cement plant. Two MHE units with compressed air as the working fluid are installed to recover the waste heat. The first unit on the main stack has four pairs of shell and tube heat exchangers. The second heat recovery unit is installed on a clinker quenching system. This unit operates with three pairs of shell and tube heat exchangers. The recovered heat is converted to electricity through the MHE system and used internally within the cement plant. A predictive model and results are presented and discussed. The results show the promising performance of the MHE's capabilities for efficient generation of electricity from waste heat sources in a cement plant. The new heat recovery system increases the efficiency of the cement plant and lowers the CO 2 emissions from the clinker production process. Moreover, it reduces the amount of waste heat to the environment and lowers the temperature of the exhaust gases. - Highlights: → This paper examines the thermodynamic performance of a new Marnoch Heat Engine (MHE) that recovers waste heat to produce electricity and improve the operating efficiency of a typical cement plant. → The first unit of the MHE on the main stack has four pairs of shell and tube heat exchangers and the second heat recovery unit is installed on a clinker quenching system. → Both predicted and experimental results demonstrate the promising performance of the MHE's capabilities for efficient generation of electricity from waste heat sources in a cement plant.

An experimental study on the heat transfer characteristics of a heat pipe heat exchanger with latent heat storage. Part II: Simultaneous charging/discharging modes

International Nuclear Information System (INIS)

Liu Zhongliang; Wang Zengyi; Ma Chongfang

2006-01-01

In this part of the paper, the performance of the simultaneous charging/discharging operation modes of the heat pipe heat exchanger with latent heat storage is experimentally studied. The experimental results show that the device may operate under either the fluid to fluid heat transfer with charging heat to the phase change material (PCM) or the fluid to fluid heat transfer with discharging heat from the PCM modes according to the initial temperature of the PCM. The melting/solidification curves, the performances of the heat pipes and the device, the influences of the inlet temperature and the mass flow rate of the cold water on the operation performance are investigated by extensive experiments. The experimental results also disclose that under the simultaneous charging/discharging operation mode, although the heat transfer from the hot water directly to the cold water may vary, it always takes up a major part of the total heat recovered by the cold water due to the very small thermal resistance compared with the thermal resistance of the PCM side. The melting/solidification processes taking place in the simultaneous charging/discharging operation are compared with those in the charging only and discharging only processes. By applying a simplified thermal resistance analysis, a criterion for predicting the exact operation modes was derived and used to explain the observed experimental phenomena