WorldWideScience
1

Diffusion absorption heat pump. Diffusion-Absorptions-Waermepumpe  

Energy Technology Data Exchange (ETDEWEB)

The development of a gas-operated diffusion absorption heat pump for the heating of living spaces is described. By various improvement an energy efficiency of the prototypes of 1.5 was achieved. Structural alterations led to a lower overall height and lower production costs. The CFCs used in electric heat pumps were replaced by environmentally neutral ammonia. Compared with conventional gas heating systems, the CO2 output could be reduced by more than 30%. figs., tabs.

1992-02-01

2

Excitation of Plasma Fluctuations near ion Giro frequencies during RF Plasma Heating in URAGAN-3M Torsatron  

International Nuclear Information System (INIS)

Currentless plasma in Uragan-3M (U-3M) is produced and heated by absorption of RF power in the region of Alfven waves (AW). The process of plasma heating was explained in (2) as a result of Cherenkov absorption of energy of the fast (EM) and slow (kinetic Alfven) waves by electrons and turbulent ion heating due to excitation of short wave ion Bernstein waves (IBW). In this report we present results of studies of plasma density fluctuations showing existence of a narrow bands near the frequencies of ? ? n?ci (n=1,2,3).

2006-01-01

3

Change in pore structure of coals by activation with KOH; KOH fukatsushita sekitan no saiko kozo  

Energy Technology Data Exchange (ETDEWEB)

Three typical Japanese coals of non-coking coal, coking coal and anthracite were heat-treated with KOH, and change in their pore structure was examined by absorption of N2, X-ray diffraction and TEM observation. In addition, the relation between a coal rank and pore structure was also studied by absorption experiment of N2. In experiment, the mixture of coal and KOH in a nickel holder was heat-treated in N2 gas flow at heating rate of 2{degree}C/min, and held at a fixed temperature for one hour. To clarify the pore structure, N2 absorption isotherms were measured at -196{degree}C under nearly 76cmHg using a commercially available full-automatic absorption measurement equipment. Based on the X-ray diffraction and TEM observation results on activated coals, the relation between the N2 absorption and pore structure was ...

1996-10-28

4

Employing exergy-optimized pin fins in the design of an absorber in a solar air heater  

Energy Technology Data Exchange (ETDEWEB)

Fins serve as heat transfer augmentation features in solar air heaters; however, they increase pressure drop in flow channels. Pin fins are relatively good heat transfer augmentation features with superior aerodynamic performance, and as a result find application in some solar air heaters. The exergy optimization method is employed in sizing the pin fin. Results indicate that high efficiency of the optimized fin improves the heat absorption and dissipation potential of a solar air heater. With optimum fin efficiency and superior absorptive coating quality, useful energy losses can be minimized. Some important observations pertinent in design are made. (author)

2010-02-15

5

Combined effect of magnetic field and heat absorption on unsteady free convection and heat transfer flow in a micropolar fluid past a semi-infinite moving plate with viscous dissipation using element free Galerkin method  

British Library Electronic Table of Contents (United Kingdom)

The fully developed electrically conducting micropolar fluid flow and heat transfer along a semi-infinite vertical porous moving plate is studied including the effect of viscous heating and in the presence of a magnetic field applied transversely to the direction of the flow. The Darcy-Brinkman-Forchheimer model which includes the effects of boundary and inertia forces is employed. The differential equations governing the problem have been transformed by a similarity transformation into a system of non-dimensional differential equations which are solved numerically by element free Galerkin method. Profiles for velocity, microrotation and temperature are presented for a wide range of plate velocity, viscosity ratio, Darcy number, Forchhimer number, magnetic field parameter, heat absorption ...

2010-01-01

6

Photoacoustic response to X-ray absorption in copper and brass  

Energy Technology Data Exchange (ETDEWEB)

The X-ray photoacoustic spectra of copper and brass (64.7 wt.% Cu and 35.3 wt.% Zn) have been measured at XANES (X-ray absorption near-edge structure) regions using synchrotron radiation. These spectra were compared with optical density of X-ray spectra. It is shown that the information derived from XANES is also included in the X-ray photoacoustic spectrum which reflects the heat production processes in copper and brass. However, the results showed that the increases and changes of the photoacoustic signal were different from those of the X-ray absorption coefficient at XANES regions. (author).

1990-09-01

7

Simplified solar fraction estimation for space and water heating at dod installations. appendix c. water heating nomographs. Final report  

Energy Technology Data Exchange (ETDEWEB)

This report contains a set of nomographs which can be used to estimate the average annual solar fraction for solar space and water heating at a large number of DOD facilities. The solar fraction estimated from the nomograph is in close agreement with F-Chart 3.0 and allows for variation of the following parameters: annual load, collector area, collector transmittance-absorptance coefficient, and collector overall loss coefficient.

1982-09-01

8

Simplified solar fraction estimation for space and water heating at DOD installations. appendix b. space heating nomographs. Final report  

Energy Technology Data Exchange (ETDEWEB)

A set of nomographs is presented which can be used to estimate the average annual solar fraction for solar space and water heating at a large number of DOD facilities. The solar fraction estimated from the nomograph is in close agreement with F-Chart 3.0 and allows for variation of the following parameters: annual load, collector area, collector transmittance-absorptance coefficient, and collector overall loss coefficient.

1982-09-01

9

Glass-heat-pipe evacuated-tube solar collector  

Science.gov (United States)

A glass heat pipe is adapted for use as a solar energy absorber in an evacuated tube solar collector and for transferring the absorbed solar energy to a working fluid medium or heat sink for storage or practical use. A capillary wick is formed of granular glass particles fused together by heat on the inside surface of the heat pipe with a water glass binder solution to enhance capillary drive distribution of the thermal transfer fluid in the heat pipe throughout the entire inside surface of the evaporator portion of the heat pipe. Selective coatings are used on the heat pipe surface to maximize solar absorption and minimize energy radiation, and the glass wick can alternatively be fabricated with granular particles of black glass or obsidian.

1981-08-06

10

A hydroxide mixture as working fluid for absorption heat pumps  

Energy Technology Data Exchange (ETDEWEB)

Basic experimental investigations were carried out with an aqueous solution of a mixture of KOH and NaOH for use as an absorbent in absorption heat pumps. Due to its thermophysical properties this mixture allows temperature lifts from evaporator to absorber of more than 75 K (135 F) in a single-stage absorption chiller. Thermophysical and hydrodynamical properties of the solution were measured. Vapor-liquid-equilibrium data and specific heat capacities were determined for concentrations ranging from 35% up to 75% and temperatures up to 200 C (392 F). From these data the enthalpy of the solution was calculated. Additionally the crystallization temperatures, the density, and the viscosity of the solution were determined. The experimental equipment is described. The data are presented as polynomials and diagrams including experimental accuracy. An apparatus was constructed to measure ...

1996-11-01

11

An experimental integrated absorption heat pump effluent purification system. Pt. 1: Operating on water/lithium bromide solutions  

Energy Technology Data Exchange (ETDEWEB)

The merits of single stage absorption heat pumps coupled to simple distillation for effluent treatment are discussed. An experimental integrated absorption heat pump effluent purification system (IAHPEPS) was built and operated with water-lithium bromide as a working mixture. This unit has been used to raise the temperature and hence, the vapour pressure of the impure water contained in one vessel, to the point where pure water vapour will distil from impure effluent solution (tap water or brine) and condense in a second vessel used to collect pure water. Pure effluent production rates of between 0.5 and 4.3 kg h{sup -1} were obtained. The actual coefficient of performance (COP{sub A}) and the heat pump effectiveness varied from 1.1 to 1.4 and 0.58 to 0.72, respectively. The results from the small scale systems indicate the likely results from industrial scale units which could be ...

1999-05-01

12

FUV and X-ray absorption in the Warm-Hot Intergalactic Medium  

CERN Document Server

The Warm-Hot Intergalactic Medium (WHIM) arises from shock-heated gas collapsing in large-scale filaments and probably harbours a substantial fraction of the baryons in the local Universe. Absorption-line measurements in the ultraviolet (UV) and in the X-ray band currently represent the best method to study the WHIM at low redshifts. We here describe the physical properties of the WHIM and the concepts behind WHIM absorption line measurements of H I and high ions such as O VI, O VII, and O VIII in the far-ultraviolet and X-ray band. We review results of recent WHIM absorption line studies carried out with UV and X-ray satellites such as FUSE, HST, Chandra, and XMM-Newton and discuss their implications for our knowledge of the WHIM.

2008-01-01

13

Cell model of nonisothermal gas absorption in gas-liquid bubbly media  

Energy Technology Data Exchange (ETDEWEB)

A model for combined mass and heat transfer during nonisothermal gas absorption in a two-phase gas- liquid bubbly medium with a high gas content and/or large times of gas-liquid contact is suggested. Diffusion and thermal interactions between bubbles is taken into account in the approximation of a cellular model of a bubbly medium whereby a bubbly medium is viewed as a periodic structure consisting of identical spherical cells with periodic boundary conditions at a cell boundary. Distribution of concentration of dissolved gas, temperature distribution in liquid and coefficients of mass and heat transfer during nonisothermal absorption of a soluble pure gas from a bubble by liquid are determined. In the limiting case of absorption without heat release the derived formulas recover the expressions for isothermal absorption. (orig.). With 1 ...

1996-06-01

14

Enhancement of Heat and Mass Transfer in Mechanically Contstrained Ultra Thin Films  

Energy Technology Data Exchange (ETDEWEB)

Oregon State University (OSU) and the Pacific Northwest National Laboratory (PNNL) were funded by the U.S. Department of Energy to conduct research focused on resolving the key technical issues that limited the deployment of efficient and extremely compact microtechnology based heat actuated absorption heat pumps and gas absorbers. Success in demonstrating these technologies will reduce the main barriers to the deployment of a technology that can significantly reduce energy consumption in the building, automotive and industrial sectors while providing a technology that can improve our ability to sequester CO{sub 2}. The proposed research cost $939,477. $539,477 of the proposed amount funded research conducted at OSU while the balance ($400,000) was used at PNNL. The project lasted 42 months and started in April 2001. Recent developments at the Pacific Northwest National Laboratory and Oregon State University suggest that ...

2005-01-01

15

Simplified solar fraction estimation for space and water heating at DOD installations. Final report  

Energy Technology Data Exchange (ETDEWEB)

A set of nomographs is provided which can be used to estimate the average annual solar fraction for solar space and water heating at a large number of DOD facilities. The solar fraction estimated from the nomograph is in close agreement with F-Chart 3.0 and allows for variation of the following parameters: annual load, collector area, collector transmittance-absorption coefficient, and collector overall loss coefficient.

1982-09-01

16

Third order optical nonlinearity of colloidal metal nanoclusters formed by MeV ion implantation  

Energy Technology Data Exchange (ETDEWEB)

We report the results of characterization of nonlinear refractive index of the composite material produced by MeV Ag ion implantation of LiNbO{sub 3} crystal (z-cut). The material after implantation exhibited a linear optical absorption spectrum with the surface plasmon peak near 430 nm attributed to the colloidal silver nanoclusters. Heat treatment of the material at 500 C caused a shift of the absorption peak to 550 nm. The nonlinear refractive index of the sample after heat treatment was measured in the region of the absorption peak with the Z-scan technique using a tunable picosecond laser source (4.5 ps pulse width). The experimental data were compared against the reference sample made of MeV Cu implanted silica with the absorption peak in the same region. The nonlinear index of the Ag implanted LiNbO{sub 3} sample produced at five times less fluence is on ...

1998-05-01

17

Radiant heating and cooling, displacement ventilation with heat recovery and storm water cooling: An environmentally responsible HVAC system  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the design, operation, and performance of an HVAC system installed as part of a project to demonstrate energy efficiency and environmental responsibility in commercial buildings. The systems installed in the 2180 m{sup 2} office building provide superior air quality and thermal comfort while requiring only half the electrical energy of conventional systems primarily because of the hydronic heating and cooling system. Gas use for the building is higher than expected because of longer operating hours and poor performance of the boiler/absorption chiller.

1998-12-31

18

K-edge X-ray absorption spectra of argon in sputtered aluminum films  

International Nuclear Information System (INIS)

We have measured K-edge X-ray absorption spectra of argon in sputtered aluminum films at a synchrotron radiation facility (the Photon Factory). We found that the energy and shape of white line change when the film is annealed at 500 C and the spectrum becomes resembling that of argon implanted in silicon. From the analyses of the X-ray absorption spectra and TEM observation we concluded that argon exists as very small atom clusters with a diameter less than 1 nm or exist as isolated atoms in the as-sputtered aluminum film, and that the size of the clusters become as big as 10 nm diameter when the film is heated. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

1999-01-04

19

Solar energy conversion system  

Energy Technology Data Exchange (ETDEWEB)

A solar energy collection and conversion system is disclosed in which a cassegrain mirror system is rotated about a diurnal axis, which axis is adjusted for seasonal variations in the incidence of the sun's rays on the earth's surface. A black body absorption cavity filled with translucent or transparent fluid material is used for direct absorption of the sun's rays. The incident solar energy is absorbed directly by the fluid medium. The fluid within the cavity may be maintained under extremely high pressures and temperatures in order to utilize this fluid as a heat storage medium. Such heat storage is facilitated by apparatus which permits a change in the volume of the reflective cavity in response to the temperature or pressure of the fluid within the cavity.

1981-09-01

20

Radiation receiver. Strahlungsempfaenger  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the invention is to improve a radiation receiver, consisting of a hollow body with an opening for the entry of radiation and a ceramic absorber situated in the hollow body, which absorbs the radiation energy entering through the opening, and emits it as thermal radiation to a heat medium, so that a higher efficiency can be achieved. According to the invention, the problem is solved by the fact that the absorber consists of ceramic material on the side towards the solar radiation, which has a low emission value and a high absorption value, and that the side of the absorber towards the heat medium has ceramic material of high emission value and low absorption value. This ensures that reradiation is prevented near the opening of the hollow body, and that the solar energy entering is largely absorbed in the hollow body.

1981-10-01

21

Nomographs for the optimum solar pond driven LiBr/ZnBr sub 2 /CH sub 3 OH absorption-refrigeration system  

Energy Technology Data Exchange (ETDEWEB)

The paper presents a procedure for the calculation of an absorption-refrigeration plant that uses an LiBr/ZnBr{sub 2}/CH{sub 3}OH solution and is driven throughout the year by heat received from a solar pond. The calculations for the solar pond are based on a finite-difference solution of the transient heat conduction differential equation during the year, and the operation of the refrigeration unit is simulated by the use of functions describing the thermodynamic behaviour of the working medium. On the basis of the procedure devised, correlations and nomographs are developed that describe the seasonally optimum operation of the proposed composite system. The nomographs may be employed for a first estimation in the design of such systems. (Author).

1992-07-01

22

CO{sub 2} CAPTURE BY ABSORPTION WITH POTASSIUM CARBONATE  

Energy Technology Data Exchange (ETDEWEB)

The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. Thermodynamic modeling predicts that the heat of desorption of CO{sub 2} from 5m K+/2.5 PZ from 85 kJ/mole at 40 C to 30 kJ/mole at 120 C. Mass transfer modeling of this solvent suggests that carbonate and general salt concentration play a major role in catalyzing the rate of reaction of CO{sub 2} with piperazine. Stripper modeling suggests that with the multipressure stripper, the energy consumption with a generic solvent decreases by 15% as the heat of desorption is decreased from 23.8 to 18.5 kcal/gmol. A second pilot plant campaign with 5m K+/2.5 PZ was successfully completed.

2005-01-31

23

CO2 CAPTURE BY ABSORPTION WITH POTASSIUM CARBONATE  

Energy Technology Data Exchange (ETDEWEB)

The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. Stripper modeling suggests the energy requirement with a simple stripper will be about the same for 5 m K{sup +}/2.5 m PZ and 7 m MEA. Modeling with a generic solvent shows that the optimum heat of CO{sub 2} desorption to minimize heat duty lies between 15 and 25 kcal/gmol. On-line pH and density measurements are effective indicators of loading and total alkalinity for the K+/PZ solvent. The baseline pilot plant campaign with 30% MEA has been started.

2005-04-29

24

Symplectic Integrators Designed for Simulating Soft Matter  

Science.gov (United States)

Symplectic integrators designed for simulating soft matter at constant temperature and constant pressure (or constant surface tension) are presented. In addition to the well-known merits of symplectic integrators, such as long time stability, these methods allow the estimation of thermal heat production/absorption and thus entropy differences through a simple function of the time scaling factor ?. The relative entropy estimation around crystal-liquid phase transition is given for systems with soft core repulsive potential.

2008-04-01

25

Solar expriment begins at Atlanta school. [George A. Towns Elementary School  

Science.gov (United States)

The largest solar heating and cooling system undertaken to date is now operating at the George A. Towns Elementary School in Atlanta, Georgia. It is expected to provide more than 60 percent of the building's heating and cooling requirements, using commercially available components and techniques. The Towns project is a United States Energy Research and Development Administration-sponsored experiment. The principal components of the solar heating and cooling system designed for the school--the solar collector array, the existing gas-fired boiler, the absorption chiller, and hot and cold water underground tanks to provide thermal storage--are described. To derive maximum benefit from the experiment, the system is fully instrumented for accurate measurement of performance. Environmental data, including insolation and ambient temperture, humidity, and wind conditions will be recorded. The inlet ...

1976-03-01

26

Processing technology for heat resisting resin suitable for small and high performance products. ; Semiaromatic polyamide applicable to regular injection molding. Kogata-koseinoka wo jitsugensuru tainetsu jushi no kako gijutsu. ; Tsujo no shashutsu seikei ga dekiru han hokozoku poriamido  

Energy Technology Data Exchange (ETDEWEB)

Products having balanced melting point and decomposition temperature have been developed by employing nylon 6T fundamental molecular structure and selected copolymer components, Arlen being one of the products. It has heat resistance as good as that of super-engineering plastics, low water absorption, and excellent cost-performance which can be used for normal injection molding machines. The unit price per kilogram is low when its high heat resistance is taken into consideration. The coefficient of water absorption is as low as about 1/3 of that of nylon 66, and it can be considered to be a low water absorbing amide. The molding temperature is from 320[degree]C to 350[degree]C, the decomposition temperature is 395[degree]C at 2% weight decreasing temperature, and normal injection molding can be employed. It has excellent soldering resistance, high temperature rigidity, dimensional stability, water ...

1994-05-01

27

Behavioral effects of microwaves  

Energy Technology Data Exchange (ETDEWEB)

Microwaves can produce sensations of warmth and sound in humans. In other species, they also can serve as cues, they may be avoided, and they can disrupt ongoing behavior. These actions appear to be due to heat produced by energy absorption. The rate of absorption depends on the microwave parameters and the electrical and geometric properties of the subject. We therefore, cannot predict the human response to microwaves based on data from other animals without appropriate scaling considerations. At low levels of exposure, microwaves can produce changes in behavior without large, or even measureable, changes in body temperature. Thermoregulatory behavior may respond to those low levels of heat, and thereby affect other behavior occurring concurrently. There are no data that demonstrate that behavioral effects of microwaves depend on any mechanism other than reactions to heat. Our ...

1980-01-01

28

Synergistic effect of different phase on the photocatalytic activity of visible light sensitive silver antimonates  

British Library Electronic Table of Contents (United Kingdom)

We investigated phase transition of ilmenite-type AgSbO3 to pyrochlore by post-heat treatment and the synergy effect of the mixed phases of AgSbO3 on the photocatalytic activities to enhance the activities. The AgSbO3 with an ilmenite structure was prepared by a cation-exchange method. Phase transition from the ilmenite to pyrochlore occurred by proper control of post-heat treatment. The sample that was obtained by post-heat treatment of ilmenite-type AgSbO3 at 660^oC for 3h consisted of both of the ilmenite and pyrochlore phases, and the sample at 685^oC for 4h mainly consisted of the pyrochlore phase. Together with an increase in the ratio of the pyrochlore phase, the optical absorption spectra blue-shifted. The band gaps of single phases of the ilmenite and the pyrochlore were 2.4 and 2...

2010-01-01

29

A numerical solution of unsteady MHD convection heat and mass transfer past a semi-infinite vertical porous moving plate using element free Galerkin method  

British Library Electronic Table of Contents (United Kingdom)

In this paper, the unsteady MHD free convection heat and mass transfer of viscous fluid flowing through a Darcian porous regime adjacent to a moving vertical semi-infinite plate under Soret and Dufour effect have been examined. Viscous dissipation effects are included in the energy equation. A uniform magnetic field is applied transversely to the direction of the flow. The differential equations governing the problem have been transformed by a similarity transformation into a system of non-dimensional differential equations which are solved numerically by element free Galerkin method. The influence of Grashof number (Gr), magnetic parameter (M), heat absorption parameter (Q), permeability parameter (K), Schmidt number (Sc), Soret number (Sr), and Dufour number (Du) on the velocity, tempera...

2010-01-01

30

Synthesis and enhanced light absorption of alumina matrix nanocomposites containing multilayer oxide nanorods and silver nanoparticles  

British Library Electronic Table of Contents (United Kingdom)

In this paper, multilayer oxide nanorods were deposited in the nanopores of anodic aluminum oxide (AAO) via solution infiltration followed by heat treatment. The nanorods have a core-shell structure. First, the shell (nanotube) with the thickness of about 40nm was made of TiO"2 through the hydrolysis of (NH"4)"2TiF"6. Second, silver nanoparticles with the diameter of about 3nm were added into the TiO"2 layer through thermal decomposition of AgNO"3 at elevated temperatures. Then, cylindrical cores (nanorods) of CoO and ZnO with 200nm diameter were prepared, respectively. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize the structure and composition of the nanorods. UV-vis light absorption measurements in the wavelength range from 350 to...

2011-01-01

31

Large specific absorption rates in the magnetic hyperthermia properties of metallic iron nanocubes  

CERN Document Server

We report on the magnetic hyperthermia properties of chemically synthesized ferromagnetic 11 and 16 nm Fe(0) nanoparticles of cubic shape displaying the saturation magnetization of bulk iron. The specific absorption rate measured on 16 nm nanocubes is 1690+-160 W/g at 300 kHz and 66 mT. This corresponds to specific losses-per-cycle of 5.6 mJ/g, largely exceeding the ones reported in other systems. A way to quantify the degree of optimization of any system with respect to hyperthermia applications is proposed. Applied here, this method shows that our nanoparticles are not fully optimized, probably due to the strong influence of magnetic interactions on their magnetic response. Once protected from oxidation and further optimized, such nano-objects could constitute efficient magnetic cores for biomedical applications requiring very large heating power.

2010-01-01

32

Electron cyclotron power absorption in plasmas with non-Maxwellian electron velocity distributions  

International Nuclear Information System (INIS)

Tokamaks with sufficiently strong supplementary heating develop non-Maxwellian electron velocity distributions. Because the absorption of electron cyclotron power is proportional to #nabla#_Vf, even small deviations from a Maxwellian distribution can significantly affect power deposition. Following an approach used to study microinstabilities in a plasma with an arbitrary, numerically specified, electron distribution, we have developed a computational module to study electron cyclotron power deposition in plasmas that have distributions motivated by those in actual tokamaks. Also, we compare the deposition results obtained using an energy balance approach with those obtained using a Taylor expansion of the dielectric tensor. We illustrate the limitations of the latter approach.

1993-04-01

33

CO2 CAPTURE BY ABSORPTION WITH POTASSIUM CARBONATE  

Energy Technology Data Exchange (ETDEWEB)

The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. CO{sub 2} mass transfer rates are second order in piperazine concentration and increase with ionic strength. Modeling of stripper performance suggests that 5 m K{sup +}/2.5 m PZ will require 25 to 46% less heat than 7 m MEA. The first pilot plant campaign was completed on June 24. The CO{sub 2} penetration through the absorber with 20 feet of Flexipac{trademark} 1Y varied from 0.6 to 16% as the inlet CO{sub 2} varied from 3 to 12% CO{sub 2} and the gas rate varied from 0.5 to 3 kg/m{sup 2}-s.

2004-07-29

35

Effects of lithium iodide doping on devolatilization characteristics of brown coals; Yoka lithium no tenka ga kattan no kanetsu henka katei ni oyobosu eikyo  

Energy Technology Data Exchange (ETDEWEB)

In order to discuss effects of lithium iodide (LiI) doping on condensation structure of brown coals during heating, spectral changes were measured by using an in-situ FT-IR. It was found that the LiI doping accelerates weight reduction due to heating, and the doping effect is affected by coal structure. Both of Loy Yang (LY) coal and its LiI doped coal (DLY) had absorption intensity of the FT-IR spectra decreased with rising temperature, and the absorption center belonging to an OH group shows different shifts between the LY and DLY coals. This indicates that the LiI doping has affected the change in hydrogen bonding patterns associated with heating. Both of South Banko (SB) and LY coals had the absorption spectral intensity in the OH group decreased as the weight reduction (conversion) rate increased. Reduction in the OH groups associated with ...

1996-10-28

36

THERMODYNAMICS AND KINETICS OF AQUEOUS PIPERAZINE WITH POTASSIUM CARBONATE FOR CARBON DIOXIDE ABSORPTION  

Energy Technology Data Exchange (ETDEWEB)

This work proposes an innovative blend of potassium carbonate (K{sub 2}CO{sub 3}) and piperazine (PZ) as a solvent for CO{sub 2} removal from combustion flue gas in an absorber/stripper. The equilibrium partial pressure and the rate of absorption of CO{sub 2} were measured in a wetted-wall column in 0.0 to 6.2 m K{sup +} and 0.6 to 3.6 m PZ at 25 to 110 C. The equilibrium speciation of the solution was determined by {sup 1}H NMR under similar conditions. A rigorous thermodynamic model, based on electrolyte non-random two-liquid (ENRTL) theory, was developed to represent equilibrium behavior. A rate model was developed to describe the absorption rate by integration of eddy diffusivity theory with complex kinetics. Both models were used to explain behavior in terms of equilibrium constants, activity coefficients, and rate constants. The addition of potassium to the amine increases the concentration of CO{sub 3}{sup 2-}/HCO{sub 3}{sup -} in ...

2005-04-18

37

Analysis and design of an ultra-high-temperature, hydrogen-fueled MHD generator as an open cycle power supply  

Energy Technology Data Exchange (ETDEWEB)

The theoretical analysis of a partially-ionized hydrogen gas flow (gas temperatures of approximately 10,000 to 20,000 K) through a particular class of magnetohydrodynamic (MHD) generators and the preliminary design of these MHD generators as open cycle, electric power supplies are performed. Analysis of the gas flow through these ultra-high temperature MHD generators requires a coupled gas dynamics/radiative heat transfer solution. Gas dynamics are modeled by a set of quasi-one-dimensional, nonlinear differential equations which account for friction, convective and radiative heat transfer and the interaction between the ionized gas and applied magnetic field. Radiative heat transfer is modeled using non-gray, absorbing-emitting two- and three-dimensional P-1 approximations which permit an arbitrary variation of the spectral absorption coefficient with frequency. Gas dynamics and radiative ...

1990-01-01

38

Manufacturing method of zirconium alloy structural material for reactor core having excellent corrosion resistance, especially, uniform corrosion resistance and hydrogen absorption resistance  

International Nuclear Information System (INIS)

The corrosion resistance of zircaloy is affected by conditions of heat treatment in the manufacturing steps to be formed into a final product as a structural material. In the manufacturing method of the present invention, a Zr alloy controlled to contain Sn: 0.8 to 1.2wt%, Fe: 0.17 to 0.28wt%, Cr: 0.05 to 0.15wt%, Ni: 0.04 to 0.10wt%, Nb: 0.01 to 0.09wt%, oxygen: 1,000 to 1,500ppm and Si, an Si impurity at a concentration of 120ppm or less and balance of Zr is melted into a cast piece, to which #beta# hardening is applied. Then, rolling and annealing treatment are applied so that the total heat input amount to the material: #SIGMA#Ai ranges from 1 x 10"-"1"9 to 1 x 10"-"1"7. With such procedures, a Zr alloy structural material for a reactor core having excellent homogeneous corrosion resistance and hydrogen absorption resistance for a long period of time while having a sufficient strength can be obtained even in a case ...

1997-01-17

39

MTX diagnostic and timing system for free-electron laser heating experiments  

International Nuclear Information System (INIS)

In the microwave tokamak experiment (MTX) program, we are concentrating on experiments using intense, free-electron laser (FEL) generated microwave pulses. In initial FEL experiments, several diagnostic instruments were operated during injection of microwave pulses with peak powers to 0.2 GW at durations of 10 ns. Fixed and spatially scanning microwave detectors and receivers and a 48-element calorimeter on the inside wall of MTX diagnosed the GW-level FEL microwave pulses. With these diagnostics, linear-wave absorption and efficiencies of transmission through the quasi-optical transport system were studied. In addition, several radially resolved measurements of plasma density, temperature, and emission were made during FEL injection and were used in the analysis of microwave absorption data. A timing system, slaved to the FEL pulse arrival time, is capable of accuracy to a few nanoseconds in order to allow measurement of ...

40

RADSOLVER: a computer program for calculating spectrally-dependent radiative heat transfer in solar cavity receivers  

Energy Technology Data Exchange (ETDEWEB)

RADSOLVER is a computer program which calculates the radiation energy transport in cavity type receivers having an arbitrary number of apertures through which collimated beams of solar radiation enter. In contrast to the common assumption of gray (or semi-gray) surfaces used in the modeling of radiation transport, RADSOLVER accounts for the wavelength-dependence of emission, absorption and reflection with a band model of the radiative properties. It is intended that this report serve both as an instruction manual for the use of the RADSOLVER code and a vehicle for presenting the underlying theory. Illustrative examples along with input and output are presented.

1981-09-01

41

LET-dependence of the trapping parameters in TLD-100 determined with a computerised curve fitting method  

International Nuclear Information System (INIS)

With a computerized curve fitting method the trapping parameters of TLD-100 chips were calculated after #alpha#-, #beta#- and #gamma#-irradiation. The absorption of radiation produces an additional glow peak at 250 deg C, and the dominant one arises at 280 deg C. After the analysis of the glow curves only a little LET-dependence of the trap depths and that of the half widths was detected. The charge densities after irradiation before heating of the taps responsible for the high temperature glow peaks (T>240 deg C) show a LET-dependence. (author).

1985-10-22

42

Environmental scanning electron microscopy  

Energy Technology Data Exchange (ETDEWEB)

The ElectroScan environmental scanning electron microscope (ESEM) is one of the most exciting new developments in the field of Electron Microscopy. The ESEM differs from conventional Scanning Electron Microscopes (SEM) by being able to examine materials including liquids and oils in their natural state with no prior sample preparation. Accessory equipment, cooling, heating and manipulating devices allow the manipulation of samples thus making it possible for the first time to image dynamic processes such as wetting, drying, absorption, corrosion, melting, crystallisation, curing and fracturing at high magnification. Papers concerning the historical development of the ESEM are given in a bibliography at the end of this paper. 24 refs., 18 figs.

1994-12-31

43

Analysis of the thermal performance of dynamic solar systems  

Energy Technology Data Exchange (ETDEWEB)

This article proposes a model for estimating the effect of the overall thermal resistance of the absorber and the coolant on a solar thermal energy system utilizing advanced heat transfer mediums. Two equations can be used to model a dynamic system: one for the maximum conversion efficiency and one to specify the constraint that, in quasi-steady state, the net energy collected must be transferred to the coolant. These two equations define a constrained optimization problem in two variables, the fluid and the absorber temperatures. The results present interesting implications for liquid metal, direct absorption, and solar evaporating systems.

1996-03-01

44

Study on tritium activity build-up in moderator and primary heat transport systems in 540 MWe reactor  

International Nuclear Information System (INIS)

Tarapur Atomic Power Station unit-4 is first 540 MWe pressurized heavy water reactor. Heavy water is used as the coolant and moderator. With reactor operation tritium is formed by absorption of neutron by Deuterium atoms. Experience in the 220 MWe indicates that tritium is main contributor to the internal dose of radiation workers. Study on Tritium build up in Primary Heat Transport (PHT) and Moderator (MOD) system was carried out at the initial stage of the operation of the unit-3 and 4. This paper brings out tritium activity buildup in the PHT and MOD systems and its comparison with 220 MWe reactors. This paper helps in estimation of the internal dose contribution to the radiation workers at TAPS 3 and 4. (author)

2006-11-13

45

Study on tritium activity build-up in moderator and primary heat transport (PHT) systems in 540 MWe reactor  

International Nuclear Information System (INIS)

Tarapur Atomic Power Station unit-4 is first 540 MWe pressurized heavy water reactor. Heavy water is used as the coolant and moderator. With reactor operation tritium is formed by absorption of neutron by deuterium atoms. Experience in the 220 MWe indicates that tritium is main contributor to the internal dose of radiation workers. Study on tritium build up in Primary Heat Transport (PHT) and Moderator (MOD) system was carried out at the initial stage of the operation of the unit-4. This paper brings out tritium activity buildup in the PHT and MOD systems and its comparison with 220 MWe reactors. This paper helps in estimation of the internal dose contribution to the radiation workers at TAPS 3 and 4. (author)

2005-11-23

46

Electron cyclotron resonance heating and current drive  

Energy Technology Data Exchange (ETDEWEB)

A brief summary of the theory and experiments on electron- cyclotron heating and current drive is presented. The general relativistic formulation of wave propagation and linear absorption is considered in some detail. The O-mode and the X-mode for normal and oblique propagation are investigated and illustrated by several examples. The experimental verification of the theory in T-10 and D- III-D is briefly discussed. Quasilinear evolution of the momentum distribution and related applications as, for instance, non linear wave, damping and current drive, are also considered for special cases of wave frequencies, polarization and propagation. In the concluding section we present the general formulation of the wave damping and current drive in the absence of electron trapping for arbitrary values of the wave frequency. (Author) 13 refs.

1992-07-01

47

Absorption of plutonium in the iron-deficient rat  

International Nuclear Information System (INIS)

Iron deficiency did not enhance absorption of plutonium following intragastric gavage of rats. Absorption of plutonium citrate in both control and iron-deficient rats was about 0.03% of the administered dose.

1977-05-01

48

Carbon dioxide absorption with aqueous potassium carbonate promoted by piperazine  

Energy Technology Data Exchange (ETDEWEB)

Many commercial processes for the removal of carbon dioxide from high-pressure gases use aqueous potassium carbonate systems promoted by secondary amines. This paper presents thermodynamic and kinetic data for aqueous potassium carbonate promoted by piperazine. Research has been performed at typical absorber conditions for the removal of CO{sub 2} from flue gas. Piperazine, used as an additive in 20-30 wt% potassium carbonate, was investigated in a wetted-wall column using a concentration of 0.6 m at 40-80{sup o}C. The addition of 0.6 m piperazine to a 20 wt% potassium carbonate system decreases the CO{sub 2} equilibrium partial pressure by approximately 85% at intermediate CO{sub 2} loading. The distribution of piperazine species in the solution was determined by proton NMR. Using the speciation data and relevant equilibrium constants, a model was developed to predict system speciation and equilibrium. The addition of 0.6 m piperazine to 20 wt% potassium carbonate increases the rate ...

2004-09-01

49

Carbon dioxide absorption with aqueous potassium carbonate promoted by piperazine  

Energy Technology Data Exchange (ETDEWEB)

This paper presents thermodynamic and kinetic data collected for aqueous blends of piperazine (PZ), an ethylamine, and potassium carbonate (K{sub 2}CO{sub 3}). Mixtures of K{sup +} and PZ have been investigated in a wetted-wall column at 40 to 80{sup o}C, typical conditions for an industrial absorber. The addition of 0.6 m PZ to 20 wt% (3.6 m) K{sub 2}CO{sub 3} increases the rate of CO{sub 2} absorption by a factor of ten from the value in unpromoted solutions at 60{sup o}C. The addition of PZ increases the heat of absorption from 4 kcal/mol in 3.6 m K{sup +} to 10 kcal/mol when 0.6 m PZ is added. The capacity, ranging from 0.4 to 0.7 mol-CO{sub 2}/kg-H{sub 2}O, approaches that of monoethanolamine (MEA) solutions and seems to be a strong function of K{sup +} concentration. Speciation of the solution was obtained using proton nuclear magnetic reasonance (NMR), verifying and quantifying the presence of three PZ species. An ...

2003-07-01

50

Thermal action of 2. 45 GHz microwaves on the cytoplasm of Chinese hamster cells  

Energy Technology Data Exchange (ETDEWEB)

In order to demonstrate possible specific effects of microwaves at the cellular level V-79 Chinese hamster cells were exposed to 2.45-GHz radiation at power levels of 20-200 mW/cm2 and at specific absorption rates of 10-100 mW/g. Intracellular cytoplasmic changes were observed by fluorescence polarization using a method based on the intracellular enzymatic hydrolysis of nonfluorescent fluorescein diacetate (FDA). At levels of absorbed energy below 90 J/g, modifications of microviscosity and mitochondrial state were absent, but a slight stimulation of enzymatic hydrolysis of FDA was observed which may be explained by microwave-induced alterations of cellular membranes possibly due to differences in heating pattern of microwaves compared to water-bath heating. At levels of absorbed energy above 90 J/g, the decrease of enzymatic hydrolysis of FDA, increase in degree of polarization, and increase of permeation of the ...

1984-01-01

51

Microwave radiation effects on the thermally driven oxidase of erythrocytes  

Energy Technology Data Exchange (ETDEWEB)

Sheep red blood cells (SRBCs) were labelled with a concanavalin A-luminol-bovine serum albumin conjugate specific for the transmembrane anion transport protein (Band 3) and exposed to 2450-MHz continuous-wave microwave radiation at an average specific absorption rate of 91W/kg for 10 min. The temperature was held constant at 25, 37, 40, 42, or 45C with an airflow heat-exchange system. Following exposure to microwave or air heating, the decrease in residual base-activated chemiluminescence (CL) of the SRBCs was measured as an indication of infield oxidase activity. Air heating resulted in a significant decrease in residual CL at temperatures above 37C (74% decrease at 45C). Microwave radiation inhibited the decline in residual CL above 37C. At 45C the inhibition was 40%. The results suggest microwave radiation either reversibly altered the thermodynamics of oxygen binding to haemoglobin or failed to ...

1986-01-01

52

Control of adsorption by microwave irradiation; Maikuroha nado wo mochiita gas no kyuchaku datsuri seigyo  

Energy Technology Data Exchange (ETDEWEB)

Introduced herein is microwave irradiation for the adsorption and desorption of environmental pollutants. Microwaves may be used in two ways, other than through elevation of temperature of a system as a whole with the adsorbent such as activated carbon serving as the heating medium. The first is the application by which desorption is caused to take place of specified molecules. For example, zeolite that has adsorbed water is regenerated when it is irradiated with microwaves in a stream of cooling gas. This is because only the moisture is heated since zeolite is a non-carbon adsorbent that absorbs microwaves but a little. Another case is reported in which microwaves are utilized to desorb H2S, H2O, CO, etc., from molecular sieves. In the second application, coexisting materials different in absorptivity are exposed to irradiation. The adsorption of microwave-absorbent materials is inhibited while that of the others is ...

1997-01-25

53

Experience with fully operational solar-driven 10-ton LiBr/H2O single-effect absorption cooling system in Thailand  

British Library Electronic Table of Contents (United Kingdom)

A solar-driven 10-ton LiBr/H2O single-effect absorption cooling system has been designed and installed at the School of Renewable Energy Technology (SERT), Phitsanulok, Thailand. Construction took place in 2005, after which this system became fully operational and has been supplying cooling for our main testing buildings air-conditioning. Data on the systems operation were collected during 2006 and analyzed to find the extent to which solar energy replaced conventional energy sources. Here, we present these data and show that the 72m2 evacuated tube solar collector delivered a yearly average solar fraction of 81%, while the remaining 19% of thermal energy required by the chiller was supplied by a LPG-fired backup heating unit. We also show that the economics of this cooling system are domi...

2008-01-01

54

Biological effects of radiowaves and microwaves  

Energy Technology Data Exchange (ETDEWEB)

Heat production in biological materials due to absorption of radiowaves and microwaves can be used in applications as diverse as cancer treatment and cooking. However, the hazards of overexposure range from hyperthermia to cataracts and internal burns. To maximize the clinical benefits and minimize potential hazards, the biological effects of radiowaves and microwaves must be understood. Dielectric measurements can be used to determine the extent of such effects in various applications and at various levels of exposure. The values of maximum permissible exposure levels that are likely to be recommended aeat production in biological materials due to absorption of radiowaves and microwaves can be used in applications as diverse as cancer treatment and cooking. However, the hazards of overexposure range from hyperthermia to cataracts and internal burns. To maximize the clinical benefits and minimize potential hazards, the ...

1980-01-01

55

Effect of dietary constituents on the absorption of lead in the human  

International Nuclear Information System (INIS)

... biological effects body burden diet intestinal absorption lead lead 203 man

1983-03-01

56

Absorption-Electrochemical Surface Decontamination  

International Science & Technology Center (ISTC)

Development of a Comprehensive Decontamination Database and an Absorption-Electrochemical Metal Surface Decontamination Technique Combining Chemical and Electrochemical Process

57

Effect of dietary constituents on the gastrointestinal absorption of /sup 203/Pb in man  

Energy Technology Data Exchange (ETDEWEB)

The gastrointestinal absorption of lead was markedly increased in human subjects who had fasted before ingesting lead. Food in the gut was found to reduce lead absorption, and the effect of dietary constituents on /sup 203/Pb absorption was investigated. The greatest reduction in absorption was caused by minerals. This dependence of lead absorption on dietary constituents complicates the establishment of safe levels of lead in food and water.

1983-02-01

58

Some properties of atomic beam produced by laser induced ablation of Li target  

International Nuclear Information System (INIS)

Pulsed atomic beams produced in vacuum by laser induced ablation from a lithium target are analyzed by laser induced fluorescence (LIF). The 1-mixing processes induced in the n = 9, 10 Li Rydberg states by collisions with CO_2 molecules illustrate the application of the method. Resolution is limited by the 1 mm diameter of the probe laser beam. Combining LIF and absorption measurements gives n_L_i as a function of time at various distances from the target surface. The investigation of the Li-C0_2 1-mixing process in a heat pipe oven proved impossible due to the high reactivity of Li with C0_2. This problem was solved by renewing the Li atoms at each laser shot. Values obtained for n = 9, n = 10 are k = 17 x 10"-"8 and 15 x 10"-"8 cc/sec, respectively.

59

Soliton microdynamics and thermal conductivity of uranium nitride at high temperatures  

British Library Electronic Table of Contents (United Kingdom)

The microdynamics of soliton waves and localized modes of nonlinear vibrations of the acoustic and optical types in uranium nitride has been investigated. It has been shown that, with an increase in the excitation energy in the spectral gap between the bands of optical and acoustic phonons, the energies of solitons increase, whereas the energies of local modes decrease. The previously experimentally observed unidentified quasi-resonant features, which shift in the gap with variations in the temperature, can represent the revealed soliton waves and local modes. The microdynamics of heat conduction of uranium nitride has been studied for the stochastic generation of soliton waves and local modes in the case of spatially distant energy absorption. The thermal conductivity coefficient determin...

2011-01-01

60

Method for determining hydrogen mobility as a function of temperature in superconducting niobium cavities  

Energy Technology Data Exchange (ETDEWEB)

A method for determining the mobility of hydrogen as a function of temperature in superconducting niobium cavities comprising: 1) heating a cavity under test to remove free hydrogen; 2) introducing hydrogen-3 gas into the cavity; 3) cooling the cavity to allow absorption of hydrogen-3; and 4) measuring the amount of hydrogen-3 by: a) cooling the cavity to about 4.degree. K while flowing a known and regulated amount of inert carrier gas such as argon or helium into the cavity; b) allowing the cavity to warm at a stable rate from 4.degree. K to room temperature as it leaves the chamber; and c) directing the exit gas to an ion chamber radiation detector.

2008-03-11

61

Hydromagnetic free convection currents effects on boundary layer thickness  

Energy Technology Data Exchange (ETDEWEB)

In this study we discuss an unsteady free convection MHD flow past semi-infinite vertical porous plate. We have considered the flow in the presence of a strong magnetic field and therefore the electromagnetic force is very large. This brings in the phenomenon of Hall and Ion-slip currents. The effects of these two parameters together with that of viscous dissipation and radiation absorption among others on velocity, temperature and concentration profiles are presented. The profiles are presented graphically. As the partial differential equations governing this problem are highly non-linear they are solved numerically by a finite difference method. It is found that in presence of heating of the plate by free convection current the velocity boundary layer thickness decreases.

2010-06-15

62

Hydromagnetic free convection currents effects on boundary layer thickness  

British Library Electronic Table of Contents (United Kingdom)

In this study we discuss an unsteady free convection MHD flow past semi-infinite vertical porous plate. We have considered the flow in the presence of a strong magnetic field and therefore the electromagnetic force is very large. This brings in the phenomenon of Hall and Ion-slip currents. The effects of these two parameters together with that of viscous dissipation and radiation absorption among others on velocity, temperature and concentration profiles are presented. The profiles are presented graphically. As the partial differential equations governing this problem are highly non-linear they are solved numerically by a finite difference method. It is found that in presence of heating of the plate by free convection current the velocity boundary layer thickness decreases.

2010-01-01

63

High pressure in situ diffraction studies of metal-hydrogen systems  

British Library Electronic Table of Contents (United Kingdom)

''Hybrid'' hydrogen storage, where hydrogen is stored in both the solid material and as a high pressure gas in the void volume of the tank can improve overall system efficiency by up to 50% compared to either compressed hydrogen or solid materials alone. Thermodynamically, high equilibrium hydrogen pressures in metal-hydrogen systems correspond to low enthalpies of hydrogen absorption-desorption. This decreases the calorimetric effects of the hydride formation-decomposition processes which can assist in achieving high rates of heat exchange during hydrogen loading-removing the bottleneck in achieving low charging times and improving overall hydrogen storage efficiency of large hydrogen stores. Two systems with hydrogenation enthalpies close to -20kJ/mol H2 were studied to investigate the h...

2011-01-01

64

Combined radiation and convection in absorbing, emitting, nongray gas-particulate tube flow  

Energy Technology Data Exchange (ETDEWEB)

The interaction of thermal radiation with conduction and convection in thermally developing absorbing, emitting, nongray gas-particulate turbulent suspension flow through a circular tube is investigated. The contribution of thermal radiation is obtained through evaluation of the total hemispherical emittance of the particulate cloud and through evaluation of single band absorptances for molecular gases, modified to account for the interaction with the particles. The governing differential equation is derived as a (nonlinear) energy equation, coupled with integral equations to find the thermal radiation contributions. The energy equation is solved numerically by an implicit finite difference method with an iterative procedure. Qualitative results for Nusselt numbers are shown for a variety and range of parameters, such as optical thickness of particulates and single molecular gas bands, relative gas band position and band width, and temperature ratios ...

1987-05-01

65

Combined radiation and convection in absorbing, emitting, non-Gray gas-particulate tube flow  

Energy Technology Data Exchange (ETDEWEB)

The interaction of thermal radiation with conduction and convection in thermally developing absorbing, emitting, non-gray gas particulate turbulent suspension flow through a circular tube is investigated. The contribution of thermal radiation is obtained through evaluation of the total hemispherical emittance of the particulate cloud and through evaluation of single band absorptances for molecular gases, modified to account for the interaction with the particles. The governing differential equation is derived as a (nonlinear) energy equation, coupled with integral equations to find the thermal radiation contributions. The energy equation is solved numerically by an implicit finite difference with its iterative procedure. Qualitative results for Nusselt numbers are shown for a variety and range of parameters, such as optical thickness of particulates and single molecular gas bands, relative gas band position and band width, and temperature ratios ...

1985-01-01

66

A simple one-step fabrication of micrometer-scale hierarchical TiO2 hollow spheres  

British Library Electronic Table of Contents (United Kingdom)

Hierarchical TiO2 hollow spheres had been prepared based on bubble templates by a simple one-step hydrothermal method. The diameter of hollow spheres was about 700nm and the shell thickness of them was 69nm. They were composed of similar spindle- or needle-like building units. Furthermore, hydrothermal time had an important influence on the morphology and crystallinity of hollow spheres. Moreover, the UV-Vis diffuse reflectance spectra of TiO2 hollow spheres heated at 150^oC for 10h showed the strongest absorption in the UV-Vis region and the Raman spectrum demonstrated the anatase sample. Additionally, a possible formation mechanism of TiO2 hollow spheres was proposed. So this novel and simple method would provide a development direction to fabricate all kinds of inorganic hollow spheres ...

2010-01-01

67

A cone concentrator for high-temperature solar cavity-receivers  

Energy Technology Data Exchange (ETDEWEB)

A cone concentrator combined with a solar cavity receiver is presented and its performance compared to a single cavity receiver. For both cases the available heat sink within the receiver is calculated. The cone concentrator suffers from a high amount of rejected rays if the exit aperture is made too small. A larger exit aperture on the other hand increases the thermal losses of the cavity. The optimum cone geometry therefore has to be found taking also into account a model of the cavity. Different operating temperatures and different values of absorption coefficients of the cavity walls are considered. A cone concentrator was built and tested at the solar furnace in Cologne. It transmits 97 percent of the rays entering the entrance aperture, which is in exact agreement with the theoretical predictions. (author)

1999-01-01

68

Simulating physiological conditions to evaluate nanoparticles for magnetic fluid hyperthermia (MFH) therapy applications  

Energy Technology Data Exchange (ETDEWEB)

Magnetite nanoparticles with high self-heating capacity and low toxicity characteristics are a promising candidate for cancer hyperthermia treatment. In order to achieve minimum dosage to a patient, magnetic nanoparticles with high heating capacity are needed. In addition, the influence of physiological factors on the heat capacity of a material should be investigated in order to determine the feasibility. In this study, magnetite nanoparticles coated with lauric acid were prepared by co-precipitation of Fe{sup 3+}:Fe{sup 2+} in a ratio of 2:1, 5:3, 3:2, and 4:3, and the pH was controlled using NaOH. Structural and magnetization characterization by means of X-ray diffractometry (XRD) and a superconducting quantum interference device (SQUID) revealed that the main species was Fe{sub 3}O{sub 4} and further showed that most of the nanoparticles exhibited superparamagnetic properties. All of the magnetic nanoparticles showed a ...

2010-01-15

69

Thermodynamic and thermoeconomic analyses of a trigeneration (TRIGEN) system with a gas-diesel engine: Part II - An application  

Energy Technology Data Exchange (ETDEWEB)

The paper is Part 2 of the study on the thermodynamic and thermoeconomic analyses of trigeneration system with a gas-diesel engine. In Part 1, thermodynamic and thermoeconomic methodologies for such a comprehensive analysis were provided, while this paper applies the developed methodology to an actual TRIGEN system with a rated output of 6.5 MW gas-diesel engine installed in the Eskisehir Industry Estate Zone, Turkey. Energy and exergy efficiencies, equivalent electrical efficiency, the Public Utility Regulatory Policies Act (PURPA) efficiency, fuel energy saving ratio, fuel exergy saving ratio and other thermodynamic performance parameters are determined for the TRIGEN system. The efficiencies of energy, exergy, PURPA and equivalent electrical efficiency of the entire system are found to be 58.97%, 36.13%, 45.7% and 48.53%, respectively. For the whole system and its components, exergetic cost allocations and various exergoeconomic performance parameters are calculated using the ...

2010-11-15

70

Thermodynamic and thermoeconomic analyses of a trigeneration (TRIGEN) system with a gas-diesel engine: Part II - An application  

International Nuclear Information System (INIS)

The paper is Part 2 of the study on the thermodynamic and thermoeconomic analyses of trigeneration system with a gas-diesel engine. In Part 1, thermodynamic and thermoeconomic methodologies for such a comprehensive analysis were provided, while this paper applies the developed methodology to an actual TRIGEN system with a rated output of 6.5 MW gas-diesel engine installed in the Eskisehir Industry Estate Zone, Turkey. Energy and exergy efficiencies, equivalent electrical efficiency, the Public Utility Regulatory Policies Act (PURPA) efficiency, fuel energy saving ratio, fuel exergy saving ratio and other thermodynamic performance parameters are determined for the TRIGEN system. The efficiencies of energy, exergy, PURPA and equivalent electrical efficiency of the entire system are found to be 58.97%, 36.13%, 45.7% and 48.53%, respectively. For the whole system and its components, exergetic cost allocations and various exergoeconomic performance parameters are calculated using the ...

2010-11-01

71

Experimental and theoretical studies on humidification-dehumidification-desalination  

Energy Technology Data Exchange (ETDEWEB)

The shortage of fresh water is increasing at alarming levels, even in temperate zones. Desalination of brackish and seawater is being considered as a solution to growing water demands. Seawater desalination can be accomplished through reverse osmosis, vapor compression, vapor absorption and thermally driven systems. The most suitable process for large-scale desalination plants is successive brine evaporation-condensation with intermediate heat recovery. However, higher process efficiency could be achieved. The use of low temperature heat sources in seawater desalination requires an efficient method of evaporation and condensation at relatively low vapor pressures. This could be achieved in a humidification-dehumidification process using circulated air to enhance evaporation of water. Simulation models, however, neglect either the heat of evaporation or the changes in air and water properties within ...

2006-07-01

72

Electron cyclotron heating  

International Nuclear Information System (INIS)

Electron cyclotron resonance heating (ECH) in BPX is planned as a possible upgrade to supplement the baseline ion cyclotron resonance frequency (ICRF) system. Eventual implementation primarily depends on the development of the required source technology. ECH offers important technical advantages over ICRF: High radio-frequency (FR) power density can be transmitted through ports (P/A >#approx# 100 MW/M"2), and the antenna need not be in contact with the plasma for efficient coupling. In particular, low-field side, linearly polarized (O-mode) power injection will suffice. By controlling the N spectrum, or by steering the antenna, the power deposition profile can be controlled during ramping of the magnetic field even with a fixed frequency source. Because of the possibility of localized power deposition, ECH is a natural candidate for controlling magnetrohydrodynamic (MHD) activity. Sawtooth oscillations may be prevented by heating in the ...

73

Study on performance of colloidal mixtures consisted of stearic acid and Na{sub 2}HPO{sub 4}.12H{sub 2}O for use as phase change materials of thermal energy storage  

Energy Technology Data Exchange (ETDEWEB)

The thermal energy storage performance and phase change stability of mix phase change materials consisted of stearic acid and Na{sub 2}PO{sub 4}.12H{sub 2}O are studied by means of Fourier transformation infrared spectrum analyses (FTIR) and Differential Scanning Calorimetry (DSC). The specific heat capacity of mix materials is also determined experimentally. The results show that all absorption peaks of functional groups and chemical bonds of stearic acid still exist, which suggests that these crystal materials composed of stearic acid and Na{sub 2}PO{sub 4}.12H{sub 2}O have good phase change stability and chemical compatibility. Thus, disadvantages caused by the subcooling of Na{sub 2}PO{sub 4}.H{sub 2}O and the low specific heat capacity of stearic acid can be solved, it is speculated that complement each other on the basis of organic/inorganic characteristics in itself is carried out for these two component materials of ...

2010-07-15

74

Specific heating power of fatty acid and phospholipid stabilized magnetic fluids in an alternating magnetic field  

Energy Technology Data Exchange (ETDEWEB)

Magnetic fluids (MFs) with a similar narrow size distribution of the iron oxide core were stabilized with lauric acid (MF 1), oleate (MF 2) or, after dialysis in the presence of liposomes, with phospholipid molecules (MF 3 and MF 4, respectively). The hydrodynamic sizes of the MF 1 and MF 3 were half those found for MF 2 and MF 4. The MFs were exposed to inductive heating in an alternating magnetic field at a frequency of 200 kHz and a maximum magnetic field strength of 3.8 kA m{sup -1}. Specific absorption rates (SAR) of 294 {+-} 42 (MF 1), 214 {+-} 16 (MF 2), 297 {+-} 13 (MF 3) and 213 {+-} 6 W g{sup -1} Fe (MF 4) were obtained. The data for MF 2 and MF 4 were identical to those found for the commercially available ferucarbotran. The biomedical relevance of the phospholipid-coated MFs is briefly discussed.

2008-05-21

75

Research on development of adsorbent for separating and collecting light element isotopes  

International Nuclear Information System (INIS)

Lithium isotopes are used as the raw material of tritium which is the fuel for fusion power generation and the material for fusion reactors, accordingly those are indispensable for future nuclear fusion power generation. As for boron isotopes, the neutron absorption corss section is very large, therefore, they are used for shielding neutrons and controlling fast neutron reactors. In order to further develop the utilization of nuclear power, it is important to develop the technology for separating and refining light element isotopes in large amount. In fiscal year 1995, the relation of the ion sieve characteristics of inorganic ion exchanger and the behavior of lithium isotope separation was examined. The behavior of forming boron complex of polyol amine was examined by B-11 NMR. These experiments and the results are reported. It was shown to be feasible that lithium is adsorbed from seawater, and isotopes are concentrated. Titanium phosphate and its ...

76

Manufacturing method of zirconium alloy-type structural material in reactor core excellent in corrosion resistance, especially in uniform corrosion resistance and hydrogen absorption resistance  

International Nuclear Information System (INIS)

A zirconium alloy comprising from 0.8 to 1.6wt% of Sn, from 0.17 to 0.25wt% of Fe, from 0.15 to 0.25wt% of Cr and from 0.01 to 0.08wt% of Ni and Si at a concentration of 120ppm or lower as an impurity and the balance of Zr is melted into cast pieces and then subjected to an #beta# annealing. It is controlled so as to satisfy Fe + Cr + Ni #<=# 0.52wt%. Then, rolling and annealing are applied so that the total heat injection amount #SIGMA#A_i to the materials is within a range of from 1 x 10"-"1"9 to 1 x 10"-"1"7. #SIGMA#A_i = #SIGMA#t_i #centre dot# exp(-Q/RT_i), in which t_i represents processing time (hour) at an ith heat treatment step after the #beta# annealing, T_i represents a processing temperature (K) in the step i. Q represents an activating energy, R represents a gas constant, and Q/R 40,000. (I.N.).

1995-08-23

77

Magnetic Fields in Massive Stars. II. The Buoyant Rise of Magnetic Flux Tubes Through the Radiative Interior  

CERN Document Server

We present results from an investigation of the dynamical behavior of buoyant magnetic flux rings in the radiative interior of a uniformly rotating early-type star. Our physical model describes a thin, axisymmetric, toroidal flux tube that is released from the outer boundary of the convective core, and is acted upon by buoyant, centrifugal, Coriolis, magnetic tension, and aerodynamic drag forces. We find that rings emitted in the equatorial plane can attain a stationary equilibrium state that is stable with respect to small displacements in radius, but is unstable when perturbed in the meridional direction. Rings emitted at other latitudes travel toward the surface along trajectories that largely parallel the rotation axis of the star. Over much of the ascent, the instantaneous rise speed is determined by the rate of heating by the absorption of radiation that diffuses into the tube from the external medium. Since the time scale for this ...

2003-01-01

78

Effects of xylitol on the absorption of /sup 203/Pb in mice and cockerels  

Energy Technology Data Exchange (ETDEWEB)

Earlier studies have indicated that xylitol may increase the absorption and urinary excretion of dietary oxalate. It has also been indicated that xylitol increases the absorption of calcium. Intestinal absorption of lead, a divalent contaminant in the diet, is in many respects similar to that of calcium. The purpose of this study was to evaluate the effects of xylitol on the intestinal absorption of lead using two different approaches: the in situ ligated intestinal loop technique in cockerels and gastric gavage in mice.

1986-07-01

79

Effect of calcium and phosphorus on the gastrointestinal absorption of /sup 203/Pb in man  

Energy Technology Data Exchange (ETDEWEB)

Calcium and phosphorus were mainly responsible for reducing the gastrointestinal absorption of lead in human subjects. The effect of calcium was greater than phosphorus, and their combined effect was more than additive. Increasing weights of calcium and phosphorus progressively reduced lead absorption. The relationship between absorption and increasing weights could be described by two negative exponentials. These effects could be explained if lead competed with calcium and phosphorus for common transport mechanisms in the gut. Milk was also found to reduce lead absorption. Adding milk to the diet of people with low dietary calcium intake could reduce the possibility of increased absorption of ingested lead.

1983-02-01

80

Trinitrotoluene: assessment of occupational absorption during manufacture of explosives.  

UK PubMed Central (United Kingdom)

Trinitrotoluene (TNT) absorption was assessed in groups of workers at two explosives factories by measuring the urinary concentrations of dinitroaminotoluene (DNAT) metabolites. DNAT was detected in...Full Text Available

1986-07-01

81

Spatially resolved IR absorption spectroscopy by optical Stark modulation  

Energy Technology Data Exchange (ETDEWEB)

The first application of optical Stark modulation has been applied to measure spatially precise Stark-modulated IR absorption spectra in a flame.

1982-12-01

82

Gamma-absorption identification of substance  

International Nuclear Information System (INIS)

The possibility of gamma-absorption identification of the analyzed substance is considered. the basic provisions of the proposed method are concentrated on the example of carbohydrates and hydrocarbons. The above method is tested experimentally on polyethylenes and polystyrene

85

Metabolic effects of microwave radiation and convection heating on human mononuclear leukocytes. Final report, January 1985-May 1986  

Energy Technology Data Exchange (ETDEWEB)

Investigated here were the effects of microwave (MW) radiation (2450-MHz, continuous-wave, mean specific absorption rate of 103.5 + or - 4.2 W/kg) and convention heating on the nonphosphorylating oxidative metabolism of human peripheral mononuclear leukocytes (96% lymphocytes, 4% monocytes) at 37 C. Metabolic activity, determined by chemiluminescence (CL) of cells challenged with luminol (5-aminO-2, 3-dihydro-1, 4-phthalazinedione) linked to bovine serum albumin, was detected with a brightness photomer. A significant stimulation after after MW exposure (p < 0.005) over total CL of matched 37 C-incubator controls was observed. A similar degree of stimulation, compared to incubator controls, was also detected after sham treatment. No significant difference existed between changes in total CL or stimulation indices of the MW and sham-exposed groups. Exposure to MW radiation, under normothermic (37 + or - 0.03 C) conditions, appears to have no ...

1986-01-01

86

Electrodeless, multi-megawatt reactor for room-temperature, lithium-6/deuterium nuclear reactions  

International Nuclear Information System (INIS)

This paper describes a reactor design to facilitate a room-temperature nuclear fusion/fission reaction to generate heat without generating unwanted neutrons, gamma rays, tritium, or other radioactive products. The room-temperature fusion/fission reaction involves the sequential triggering of billions of single-molecule, "6LiD 'fusion energy pellets' distributed in lattices of a palladium ion accumulator that also acts as a catalyst to produce the molecules of "6LiD from a solution comprising D_2O, "6LiOD with D_2 gas bubbling through it. The D_2 gas is the source of the negative deuterium ions in the "6LiD molecules. The next step is to trigger a first nuclear fusion/fission reaction of some of the "6LiD molecules, according to the well-known nuclear reaction: "6Li + D #-># 2"4He + 22.4 MeV. The highly energetic alpha particles ("4He nuclei) generated by this nuclear reaction within the palladium will cause shock and vibrations in the palladium lattices, leading ...

87

Two-gigawatt burst-mode operation of the intense microwave prototype (IMP) free-electron laser (FEL) for the microwave tokamak experiment (MTX)  

Energy Technology Data Exchange (ETDEWEB)

The MTX explored the plasma heating effects of 140 GHz microwaves from both Gyrotrons and from the IMP FEL wiggler. The Gyrotron was long pulse length (0.5 seconds maximum) and the FEL produced short-pulse length, high-peak power, single and burst modes of 140 GHZ microwaves. Full-power operations of the IMP FEL wiggler were commenced in April of 1992 and continued into October of 1992. The Experimental Test Accelerator H (ETA-II) provided a 50-nanosecond, 6-MeV, 2--3 kAmp electron beam that was introduced co-linear into the IMP FEL with a 140 GHz Gyrotron master oscillator (MO). The FEL was able to amplify the MO signal from approximately 7 kW to peaks consistently in the range of 1--2 GW. This microwave pulse was transmitted into the MTX and allowed the exploration of the linear and non-linear effects of short pulse, intense power in the MTX plasma. Single pulses were used to explore and gain operating experience in the parameter space of the IMP FEL, and finally ...

1993-10-06

88

Enrichment of trace cadmium by soybean protein for the analysis by atomic absorption method  

International Nuclear Information System (INIS)

A method for enrichment of the ppb level of cadmium in water by using the coagulation of soybean protein by adding acids or its complex-forming character with heavy metal ions was investigated. After adding fixed amounts of soybean milk and 2% sodium diethyldithiocarbamate(DDTC) aqueous solution and a suitable amount of delta-gluconic lactone (delta-GL) to a sample solution, the mixture was heated to boiling in order to coagulate the protein. The coagulum(soybean curd) was separated from the suspension by centrifugation and burned to ashes with a low temperature plasma asher. Then the cadmium enriched in it was determined by atomic absorption spectrometry. Various factors such as the pH of the sample solution, the amounts of soybean milk and the collection additives, and the concentration of NaCl in the sample solution on the recovery of cadmium were examined systematically. The best recovery was obtained under the following conditions: To a ...

1975-01-01

89

Ellipsometric and spectral measurements in the study of chemically coloured 304 stainless steel selective surfaces  

Energy Technology Data Exchange (ETDEWEB)

Ellipsometric studies and reflectance measurements on five anodized coloured 304 stainless steel samples (Brown, Violet, Blue, Light Grey and Dark Grey) are reported. The optical properties, solar absorptance and thermal emittance of samples have been obtained. Measured values of absorptance lay between 0.75-0.87 together with a near normal emittance value approx. =0.10 at 100/sup 0/C. The total hemispherical emittance has been measured at 100 and 200/sup 0/C for the sample having the best selective surface. This study shows that the blue coloured surface has the most favourable combination of radiation properties. The surface deteriorates at temperatures above 210/sup 0/C. Oxidation is assumed to be the deterioration mechanism. The different samples exhibited difference in the /PSI/ and ..delta.. parameters as determined by ellipsometry both before and after heat treatments. When brown and violet samples were coated with a ...

1982-09-01

90

Catalytic effect of niobium oxide on hydrogen storage properties of mechanically ball milled MgH{sub 2}  

Energy Technology Data Exchange (ETDEWEB)

We examined a catalytic effect of niobium oxide (Nb{sub 2}O{sub 5}) on the hydrogen storage properties of MgH{sub 2} prepared by mechanical ball milling method. The MgH{sub 2} composite doped with 1 mol% Nb{sub 2}O{sub 5} by ball milling for 20 h desorbed hydrogen up to {approx}6 mass% in the temperature range from 200 to 250 {sup o}C at the heating rate of 5 {sup o}C/min under a purified helium flow. After dehydrogenation at 200 {sup o}C, the product showed remarkable hydrogen absorption kinetics. A large amount of gaseous hydrogen up to {approx}4.5 mass% was absorbed even at room temperature under 1 MPa hydrogen pressure within 15 s and finally its capacity reached up to 5 mass%. Furthermore, the valence state of Nb{sub 2}O{sub 5} doped in MgH{sub 2} was examined by X-ray absorption near edge structure (XANES) measurement. The results indicated that additive Nb{sub 2}O{sub 5} was reduced by MgH{sub 2} during mechanical ...

2006-08-15

91

The Effect of Cocktail on Radiocarbon Analysis by Direct Absorption of Carbon dioxide  

International Nuclear Information System (INIS)

Carbon-14 was analysed by direct absorption of carbon dioxide on the mixture of organic amine compound and scintillation cocktail then counted by low level liquid scintillation counter. This method can be applied for radiocarbon dating. In this study, the effects of carbon dioxide absorption, and counting efficiency were investigated using various commercial available cocktail. It was found that permafluor V and Ready Gel showed the highest carbon dioxide absorption whereas the Permafluor V showed the highest counting efficiency

1998-12-01

98

Use of boron waste as a fluxing agent in production of red mud brick  

Energy Technology Data Exchange (ETDEWEB)

The study was directed towards determining the usability of clay and fine wastes (CW and FW) of boron from the concentrator plant in Kirka (Turkey) as a fluxing agent in production of red mud (RM) brick. Both laboratory studies on the characterization of materials and industrial-scale tests for production of bricks were carried out. CW and FW, which have similar chemical composition but include different types and amounts of oxides, were added in amounts of 5, 10 and 15wt% to RM, which consists of high amounts of Fe{sub 2}O{sub 3}, Al{sub 2}O{sub 3}, SiO{sub 2} and alkalies. Six different sets of samples have been produced and fired at 700, 800 and 900{sup o}C. Dry shrinkage of green body, bending and compressive strength, firing shrinkage, water absorption, frost resistance and harmful magnesia and lime tests on heat-treated bodies have been performed. The mineralogical and mechanical tests showed that usability of boron wastes as a fluxing ...

2006-12-15

99

Study of structural and optical properties of sprayed WO{sub 3} thin films using enhanced characterization techniques along with the Boubaker Polynomials Expansion Scheme (BPES)  

Energy Technology Data Exchange (ETDEWEB)

In this study, WO{sub 3} thin films were grown on glass substrates using an aqueous solution containing tungstate (NH{sub 4}){sub 2}WO{sub 4} as precursor. The substrate temperature incremented from 250 to 500 deg. C, by steps of 50 deg. C. The structural properties were investigated using XRD, atomic force microscopy and scanning electronic microscopy techniques. Microprobe analyses showed that a balanced stoichiometric composition was obtained for thin films prepared at T{sub s} = 350 and 400 deg. C. The X-ray diffraction analyses showed different structure crystallography in function of the substrate temperature. Moreover, films deposited at 400 deg. C were annealed in air for 2 h at 450 and 500 deg. C, respectively and the structural changes due to heat treatment were studied. Finally, the optical properties of these films were carried out using optical measurements of transmittance T({lambda}) and reflectance R({lambda}) spectra in 300-1800 nm domain. The ...

2009-11-13

100

Study of structural and optical properties of sprayed WO3 thin films using enhanced characterization techniques along with the Boubaker Polynomials Expansion Scheme (BPES)  

International Nuclear Information System (INIS)

In this study, WO3 thin films were grown on glass substrates using an aqueous solution containing tungstate (NH4)2WO4 as precursor. The substrate temperature incremented from 250 to 500 deg. C, by steps of 50 deg. C. The structural properties were investigated using XRD, atomic force microscopy and scanning electronic microscopy techniques. Microprobe analyses showed that a balanced stoichiometric composition was obtained for thin films prepared at Ts = 350 and 400 deg. C. The X-ray diffraction analyses showed different structure crystallography in function of the substrate temperature. Moreover, films deposited at 400 deg. C were annealed in air for 2 h at 450 and 500 deg. C, respectively and the structural changes due to heat treatment were studied. Finally, the optical properties of these films were carried out using optical measurements of transmittance T(?) and reflectance R(?) spectra in 300-1800 nm domain. The refractive and absorption ...

2009-11-13

101

On the off-design of a natural gas-fired combined cycle with CO{sub 2} capture  

Energy Technology Data Exchange (ETDEWEB)

During the last 15 years cycles with CO{sub 2} capture have been in focus, due to the growing concern over our climate. Often, a natural gas fired combined cycle with a chemical absorption plant for CO{sub 2} capture from the flue gases have been used as a reference in comparisons between cycles. Neither the integration of the steam production for regeneration of amines in the combined cycle nor the off-design behaviour of such a plant has been extensively studied before. In this paper, the integration of steam production for regeneration of the amines is modelled at design load and studied in off-design conditions for a combined cycle. Different ambient conditions and part-load strategies and their influence on the cycle performance are also examined. Of particular interest is a novel strategy with the possibility of longer life of gas turbine blading, with marginal loss in efficiency. The off-design performance of the combined cycle is modelled in a rigorous way ...

2007-04-15

102

Fine ceramics industrial policy for global environmental problem. Chikyu kankyo mondai to fine ceramics kanren shisaku  

Energy Technology Data Exchange (ETDEWEB)

The industrial policy of fine ceramics which is one of the new material expected to solve energy/environmental problem, is described. Fine ceramics are possessed with the characteristics like surpassing electromagnetic properties, heat resistance, high strength, etc. and its use as highly efficient power generation plant material, functional material for various sensors/electronic, and activation of existing industries are cited. As for the reclamation of global environment, promotion of saving energy in a global scale, development of innovative environmental technology and increase of carbon dioxide absorption source are described. Furthermore, research and development work in Japan on global environmental industrial technology for 1992 to 1993, new sunshine project and technical developments relating to fine ceramics are explained. As for the results of research and development, the results from the case study of 300kw type gas turbine are ...

1993-04-01

103

Effects of CdCl2 treatment on properties of CdTe thin films grown by evaporation at low substrate temperatures  

International Nuclear Information System (INIS)

The structural, morphological and optical properties of vacuum-evaporated CdTe thin films were investigated as a function of substrate temperature and post-deposition annealing without and with CdCl2/treatment at 400 C for 30 min. Diffraction patterns are almost the same exhibiting higher preferential orientation corresponding to (111) plane of the cubic phase. The intensity of the (111) peak increased with the CdCl2/annealing treatment. The microstructure observed for all films following the CdCl2/annealing treatment are granular, regardless of the as-deposited microstructure. The grain sizes are increased after the CdCl2/annealing treatment but now contain voids around the grain boundaries. The optical band gaps, Eg, were found to be 1.50, 1.50 and 1.48 eV for films deposited at 200 K and annealed without and with CdCl2/treatment at 400 C for 30 min respectively. A progressive sharpening of the absorption edge upon heat treatment particularly ...

2007-09-01

104

Contrasting Kondo behavior and resonant inverse photoemission spectra of CeTSi{sub 3} and CeTGe{sub 3} (T=Rh and Ir)  

Energy Technology Data Exchange (ETDEWEB)

We have investigated CeTSi{sub 3} and CeTGe{sub 3} (T = Rh and Ir) by measuring the magnetic susceptibility, specific heat, electrical resistivity, the resonant inverse photoemission (RIPES) and M{sub IV,V} x-ray absorption spectra (XAS). The germanides showed a very weak Kondo effect, but the silicides exhibited a negatively large Weiss temperature (approx. = -130 K) and a lnT dependence of magnetic resistivity above 100 K, suggesting that they are a Kondo-lattice compound with a high Kondo temperature T{sub K} (approx. = 100 K). The Curie-Weiss law suggests that Ce atoms in these compounds remain close to 3+ down to about 150 K in spite of their high T{sub K}. In general, both RIPES and M{sub IV,V} XAS support their apparently stable valency. (author)

1999-02-28

105

Chalk point cooling tower project: effects of simulated saline cooling tower drift on woody species. Master's thesis  

Science.gov (United States)

Cooling towers of power plants are used to dissipate waste heat into the atmosphere. If saline water is used for cooling, a saline aerosol known as drift is released into the atmosphere. Drift effects on vegetation are not well known. To simulate drift for a field study, cooling tower basin water was sprayed thirty separate times during a 46-day period in 1975 on Virginia pine (Pinus virginiana), flowering dogwood (Cornus florida), tulip tree (Liriodendron tulipfera), and California privet (Ligustrum ovalifolium), Norway spruce (Picea abies), and white ash (Fraxinus americana) were added in 1976 and all trees were sprayed 43 times during a 59-day period. Only dogwood leaves showed significant injury. Absence of injury on other species was probably due to the ability of their leaves to exclude, or reduce absorption of, toxic concentrations of the ions supplied.

1977-07-01

106

Alloys and oxides on carbon-supported Pt-Sn electrocatalysts for ethanol oxidation  

Energy Technology Data Exchange (ETDEWEB)

This work reports studies of ethanol oxidation on Pt-Sn/C catalysts with nearly the same particle size and identical overall composition having different amounts of oxide and alloyed phases. Results of characterization of physical properties by transmission electron microscopy (TEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), X-ray photoelectron spectroscopy (XPS), and in situ dispersive X-ray absorption spectroscopy (DXAS) are presented. The variation in the amount of oxide and alloyed phases, promoted by heat treatments in mild temperature conditions, does not produce any significant particle growth. Cyclic voltammetry and oxidation of adsorbed CO in acid medium are used to probe the surface conditions. Data on the electrocatalytic activity towards ethanol oxidation, obtained by potential sweeps and chronoamperometry, are discussed and correlate well with the physical properties. This study, carried out in the absence ...

2010-06-01

107

Interaction of water with epoxy.  

Energy Technology Data Exchange (ETDEWEB)

The chemistries of reactants, plasticizers, solvents and additives in an epoxy paint are discussed. Polyamide additives may play an important role in the absorption of molecular iodine by epoxy paints. It is recommended that the unsaturation of the polyamide additive in the epoxy cure be determined. Experimental studies of water absorption by epoxy resins are discussed. These studies show that absorption can disrupt hydrogen bonds among segments of the polymers and cause swelling of the polymer. The water absorption increases the diffusion coefficient of water within the polymer. Permanent damage to the polymer can result if water causes hydrolysis of ether linkages. Water desorption studies are recommended to ascertain how water absorption affects epoxy paint.

2009-07-01

108

Gastrointestinal absorption of transuranic elements by rats  

International Nuclear Information System (INIS)

Absorption of ''organically bound'' "2"3"3U and "2"4"1Am from gastrointestinal tracts of adult rats was twice that of the inorganic nitrate form. There was no difference between transport of "2"3"2U and "2"3"3U by adult rats, but "2"3"2U absorption by newborn rats was four times that of "2"3"3U. Absorption of "2"3"8Pu nitrate through the gut of the newborn is relatively insensitive to dose but incorporation in the gut mucosa saturates at high dose levels. Absorption of "2"3"8Pu is greater at 4 hr of age than at 24 hr.

1977-05-01

109

Gastrointestinal absorption of lead-203 chloride in man  

International Nuclear Information System (INIS)

Studies of the gastrointestinal absorption of lead-203 chloride were carried out on 11 normal subjects, 7 males and 4 females. Whole body counting of these subjects after administration of 74 kBq (2 #mu#Ci) of cyclotron-produced lead-203 chloride showed a mean absorption of 21.3% of the dose with a range from 10.4 to 47.7%. The male subjects had a lower mean absorption of 18.1% of the dose compared with a mean of 26.9% in the females. Although this difference did not reach statistical significance, it is postulated that male/female differences in absorption may relate to differences in iron saturation of the subjects.

110

Carbon dioxide absorption contactors: hollow fibre membranes and packed absorption columns  

Energy Technology Data Exchange (ETDEWEB)

One of the important aspects in an absorption system is the effectiveness in which the gas and liquid phases come into contact with each other. An effective absorption process will provide sufficient contacting area for the gas and liquid phases to interact upon. With this in mind, work was conducted to evaluate carbon dioxide (CO{sub 2}) absorption into aqueous solutions of monoethanolamine (MEA) using two different types of contacting devices: gas absorption membrane (GAM) modules and traditional packed columns. The performance of these two absorption devices was compared to one another using the overall mass transfer coefficient (K{sub G}a{sub v}) as a basis. The GAM module contained microporous polypropylene hollow fibre membranes and the packed absorption column contained Sulzer DX structured packing. The results indicate that GAM modules tend to have ...

2003-07-01

111

Thermoregulatory responses of rats exposed to 9. 3-GHz radio-frequency radiation  

Energy Technology Data Exchange (ETDEWEB)

Ketamine-anesthetized Sprague-Dawley rats were exposed in H orientation to far-field 9.3-GHz continuous-wave (CW) and pulsed (2 microseconds 500 pps) radiofrequency radiation (RFR) at average power densities of 30 and 60 mW/sq. cm (whole-body average specific absorption rates of 9.3 and 18.6 W/kg, respectively). Irradiation was conducted to cyclicly increase colonic temperature from 38.5 to 39.5 C. Colonic, tympanic, and subcutaneous temperatures, ECG, blood pressure, and respiratory rate were continuously recorded during experimentation. At both power densities, the subcutaneous and tympanic temperature increases significantly exceeded the colonic temperature increase. At both exposure levels, heart rate increased significantly during irradiation and returned to baseline when exposure was discontinued. Blood pressure and respiratory rate did not significantly change during irradiation. There were no significant differences between the effects of CW and pulsed RFR ...

1987-10-15

112

MTX final report  

Energy Technology Data Exchange (ETDEWEB)

The MTX experiment was proposed in 1986 to apply high frequency microwaves generated by a free-electron laser (FEL) to electron cyclotron resonance heating (ECRH) in a high field, high density tokamak. As the absorption of microwaves at the electron cyclotron resonance requires high frequencies, the opportunity of applying a free-electron laser has appeal as the device is not limited to frequencies in the microwave or long millimeter wavelength regions, in contrast to many other sources. In addition, the FEL is inherently a high power source of microwaves, which would permit single units of 10 MW or more, optimum for reactors. Finally, it was recognized early in the study of the application of the FEL based on the induction linear accelerator, that the nonlinear effects associated with the intense pulses of microwaves naturally generated would offer several unique opportunities to apply ECRH to current drive, MHD control, and other plasma ...

1994-01-01

113

Effects of field orientation during 700-MHz radiofrequency irradiation of rats  

Energy Technology Data Exchange (ETDEWEB)

Ketamine-anesthetized Sprague-Dawley rats were exposed to far-field 700-MHz continuous-wave radiofrequency radiation (RFR) in both E and H orientations. Irradiation was conducted at whole-body average specific absorption rates (SARs) of 9.2 and 13.0 W/kg (E and H, respectively) that resulted in approximately equivalent colonic specific heating rates (SHRs). Exposures were performed to repeatedly increase colonic temperature by 1 deg C (38.5 to 39.5 deg C). Tympanic, tail, left and right subcutaneous (toward and away from RFR source), and colonic temperatures, arterial blood pressure, and respiratory rate were continuously recorded. In spite of equivalent colonic SHRs and the reduced E-orientation average SAR, the right subcutaneous, tympanic, and tail SARs, SHRs and absolute temperature increases were significantly greater in E than in H orientation. The cooling rate at all monitoring sites was also significantly greater in E than in H ...

1989-01-01

114

CAV2: A PC-based computer program for predicting incident solar flux distributions inside dish cavity receivers  

Energy Technology Data Exchange (ETDEWEB)

The energy flux distribution at the aperture of cavity receivers is an important parameter that characterizes the performance of point-focusing solar concentrators. Together with simplifying assumptions about cavity absorptance, emittance, and convective losses, good estimates of the dish-receiver collection efficiency as a function of incident flux and effective cavity temperature can be obtained. For detailed design of cavity receivers, however, it is necessary to determine the incident flux distribution on the interior surfaces. This information is needed ultimately to determine the resulting energy fluxes to the working fluid, temperature distributions within the cavity, and receiver performance. Knowing the incident flux distributions provides the designer with insights such as where hot-spots are likely to occur, where heat exchange surfaces are needed, and where more detailed analysis might be warranted. Solar receivers are ...

1987-02-01

115

Absorption of carbonyl sulfide in aqueous methyldiethanolamine  

Energy Technology Data Exchange (ETDEWEB)

The absorption of carbonyl sulfide in aqueous methyldiethanolamine (MDEA) was studied over a range of temperatures and MDEA concentrations. MDEA is commonly used for selective absorption of hydrogen sulfide in the presence of carbon dioxide. However, sulfur in the form of COS may also be present and it is necessary that estimates of absorption rates of this compound be made. The objective of this study is to determine the physiochemical properties needed to predict COS absorption rates in aqueous MDEA. Free gas solubility and the diffusivity of COS in MDEA solutions were measured over the temperature range 15 to 40{sup 0}C for MDEA concentrations up to 30 weight per cent using the nitrous oxide analogy method. Solubilities were measured volumetrically in an equilibrium cell and diffusivities were measured using a laminar liquid jet absorber. The kinetics of the reaction between COS and MDEA were studied ...

1988-01-01

116

Heat Transfer Augmentation in a Compact Heat Exchange Pedestal Array.  

Science.gov (United States)

A compact heat exchanger pedestal array for augmenting heat transfer in a machine is disclosed. The compact heat exchanger pedestal array includes a wall having first and second surfaces. The first surface faces a heated flow path and the second surface p...

2004-01-01

117

Large Eddy Simulation for Heat Transfer Prediction in a Gas ...  

Science.gov (United States)

... turbine blade heat-transfer and study the heat-transfer augmentation in idealized geometry and its ... responsible for heat transfer augmentation. ...

2007-03-30

119

Investigation of Nuclide Importance to Functional Requirements Related to Transport and Long-Term Storage of LWR Spent Fuel  

Energy Technology Data Exchange (ETDEWEB)

The radionuclide characteristics of light-water-reactor (LWR) spent fuel play key roles in the design and licensing activities for radioactive waste transportation systems, interim storage facilities, and the final repository site. Several areas of analysis require detailed information concerning the time-dependent behavior of radioactive nuclides including (1) neutron/gamma-ray sources for shielding studies, (2) fissile/absorber concentrations for criticality safety determinations, (3) residual decay heat predictions for thermal considerations, and (4) curie and/or radiological toxicity levels for materials assumed to be released into the ground/environment after long periods of time. The crucial nature of the radionuclide predictions over both short and long periods of time has resulted in an increased emphasis on thorough validation for radionuclide generation/depletion codes. Current radionuclide generation/depletion codes have the capability to follow the ...

1995-01-01

120

Studies on Inhibition of Intestinal Absorption of Radioactive Strontium  

UK PubMed Central (United Kingdom)

A method is reported which permits selective suppression of absorption of radioactive strontium from ingested food material, permitting the calcium to be available to the body. Studies were carried...Full Text Available

1964-08-08

121

Seasonal changes in lead absorption in laboratory rats.  

UK PubMed Central (United Kingdom)

A retrospective study of the relationship of season to the absorption of radiolead in laboratory rats was performed using data representing 305 animals from 36 experiments over 6 calendar years. Male...Full Text Available

1987-08-01

122

Percutaneous absorption of aromatic amines in rubber industry workers: impact of impaired skin and skin barrier creams  

UK PubMed Central (United Kingdom)

BackgroundSeveral aromatic amines (AA) could cause bladder cancer and are an occupational hygiene problem in the workplace. However, little is known about the percutaneous absorption...Full Text Available

2007-06-01

123

L edge-absorption systematics of some transition-metal (Pd, Ag), main-group-metal (Sn, In), and ionic (CsI) systems  

Energy Technology Data Exchange (ETDEWEB)

The L edge absorption of Pd, Ag, Sn, In, and CsI was measured in order to study the density of states and the unoccupied d states. 4 figures. (DLC)

1982-01-01

124

Kinetics of absorption of trace iodine vapor in aqueous solution of sodium hydroxide, (2)  

International Nuclear Information System (INIS)

A liquid column was used for the experiments reported in Part 1. However, it only gives the observation of the effect of fast reaction because the liquid flow was controlled to uniform laminar flow and the contact is limited to short time of around 10 ms. In practical absorbing operation, turbulence is involved in liquid flow, and the residence time for contact is long. Hence, the absorption of trace iodine in the purified air has been experimented by using a constant interface area type stirred absorption tank. Prior to the experiment, the characteristics of the absorption tank was investigated by conducting pure carbon dioxide absorption test with purified water. It gave the conclusion that the tank was sufficiently usable for fundamental researches. In short contact time absorption, the iodine dissolved and absorbed in liquid phase is affected by reaction of hypoiodous acid and ...

1978-01-01

125

Intrinsic Factor-mediated Absorption of Cobalamin by Guinea Pig Ileal Cells  

UK PubMed Central (United Kingdom)

To investigate the fate of intrinsic factor and cobalamin during cobalamin absorption, we incubated enterocytes isolated from guinea pig ileum for periods of up to 30 min with 57Co-labeled...Full Text Available

1983-03-01

126

Glucose turnover in the post-absorptive rat and the effects of halothane anaesthesia.  

UK PubMed Central (United Kingdom)

1. Rates and rate coefficients of glucose utilization and replacement in post-absorptive rats, either conscious or under halothane anaesthesia, were determined in a thermoneutral environment by using...Full Text Available

1977-03-15

127

Continuous measurement of residual activity of an amine solution used for acid gas absorption  

Energy Technology Data Exchange (ETDEWEB)

Concentration of an amine solution for removal of hydrogen sulfides and carbon dioxide from natural gas, is tested by carbon dioxide absorption measurement in an apparatus allowing complete reaction to give reliable results.

1988-05-27

128

Absorption and diffusion of hydrogen in palladium-silver alloys by density functional theory  

Science.gov (United States)

The vibrational states, absorption energies, and diffusions of H in Pd and Pd1-xAgx(0Pd-Ag alloys should avoid the Ag-rich areas.

2002-11-01

130

Tetrakis (. mu. -pyrophosphito) diplatinum (II) Tetraanion. A potential inorganic material for the fabrication of luminescent solar concentrators  

Energy Technology Data Exchange (ETDEWEB)

In this note it is suggested that binuclear platinum(II) complexes with a solely inorganic bridging pyrophosphito ligand also possess many of the complementary advantages of inorganic and organic dyes. They are evaluated for their potential use as a luminescent solar concentrator material. The disadvantages include: the high cost of platinum; the absorption spectra in solution shows a weaker absorption at 452 nm which may cause reabsorption of emitted light; the positions of the absorption and emission maxima are not at the optimal wavelengths for absorption of sunlight and emission to a solar cell. In spite of these drawbacks the author believes the platinum complexes merit consideration for fabrication of solar concentrator devices.

1986-01-01

131

Sound absorption of tropical woods and their radiation-induced composites  

International Nuclear Information System (INIS)

This is a preliminary study on the sound absorption properties of two tropical hardwoods, Light Red Meranti and Ramin, and their wood-polymer composites. Sound absorption is measured using a standing wave apparatus. The samples are of one thickness (7 mm) and cut longitudinally. Wood-polymer composites are made by impregnating the samples with methyl methacrylate which is polymerized in situ through #gamma#-irradiation. Both woods and their composites are better sound absorbers at higher sound frequencies. With partial impregnation, the absorption coefficients are improved upon particularly in the region between 1-3 kHz. (author).

1988-01-01

132

Intraband Absorptoin of Far-Infrared Light by Electrons in ...  

Science.gov (United States)

... significant change of spontaneous radiation intensity. It is very sensitive technique allowing the observation of small changes of light absorption. ...

1999-06-18

133

Inhibition of Two-Photon Absorption in a Four-Level Atomic System with Closed-Loop Configuration  

International Nuclear Information System (INIS)

We theoretically investigate the features of two-photon absorption in a coherently driven four-level atomic system with closed-loop configuration. It is found that two-photon absorption can be completely suppressed just by properly adjusting the relative phase of four coherent low-intensity driving fields and the atomic system becomes transparent against two-photon absorption. From a physical point of view, we explicitly explain these results in terms of quantum interference induced by two different two-photon excitation channels.

2007-05-15

134

Gastrointestinal absorption of alfalfa-bound plutonium-238 by rats and guinea pigs  

International Nuclear Information System (INIS)

Rats and guinea pigs were fed "2"3"8Pu either biologically incorporated into alfalfa (by growth of the plant on soil containing Pu) or added as a solution to alfalfa, or were gavaged with a Pu solution. Depending upon the plant material fed, there appeared to be a twofold increase in "2"3"8Pu-gut absorption by the rat and a two- to fourfold increase in the guinea pig as compared with absorption from the Pu solution. The data, though limited and variable, suggest that Pu bound to plant tissue may have higher gut absorptivity than inorganic Pu in both herbivorous and nonherbivorous rodents.

1977-05-01

136

EMITTANCE AND ABSORPTANCE OF NASA CERAMIC ...  

Science.gov (United States)

... The data were transformed into total hemispherical emittance values and correlated with respect to ceramic coating thickness and temperature ...

1978-06-01

137

BOOKMARKS:  

Wastenet

Total carbon dioxide absorption per year increases from 4 lbs of CO2 in 2002 and reaches 260 lbs

138

Annual Report  

Science.gov (United States)

... energy absorption characteristics of composite sandwich panels, thermoplastic energy-absorbing subfloor structures, and shoulder belt pre- tensioners. ...

139

Spectral absorption properties of colored dissolved organic matter (CDOM) and total suspended matter (TSM) of inland waters  

Science.gov (United States)

Spectral absorption properties of total suspended matter (TSM) and colored dissolved organic matter (CDOM) are important for the use of the bio-optical model to estimate water quality parameters. This study aims to investigate the variation in the absorption coefficients of TSM and CDOM of inland waters. A total of 92 water samples were collected from Shitoukoumen Reservoir and Songhua Lake in Northeast China, analyzed for TSM and Chl-a, and measured for the absorption coefficient of TSM, CDOM and total pigments using a laboratory spectrophotometer. The absorption coefficient of TSM has been decomposed for phytoplankton and inorganic sediments. The results show that for Shitoukoumen Reservoir, CDOM has strong absorptions with shallow absorption slopes (i.e., the coefficient S in a(?)=a(?0)exp[-S(?- ?0)]) and large absorption at 355 nm; and ...

2010-08-01

140

Investigation of carbon dioxide absorption by absorbents impregnated with alkanol amines  

Energy Technology Data Exchange (ETDEWEB)

In studying the absorption of carbon dioxide by absorbents impregnated with alkanol amines, researchers used a laboratory-scale packed column to determine the overall gas-phase mass-transfer coefficients and enhancement factors. A model derived for the mechanism of the chemical reaction taking place in the interfacial layer accounts for the effect of the reaction upon the absorption rate better than other models.

1981-01-01

141

Differential optical absorption techniques for diagnostics of coal gasification. Technical progress report, October, November, December 1982  

Energy Technology Data Exchange (ETDEWEB)

The application of differential optical absorption (DOA) techniques for the in-situ determination of the chemical composition of coal gasification process streams is investigated. Absorption spectra of relevant molecular species and the temperature and pressure effects on DOA-determined spectral characteristics of these species will be determined and cataloged. A system will be configured, assembled, and tested.

1983-04-01

142

Design of absorption columns in the presence of surfactants  

Energy Technology Data Exchange (ETDEWEB)

An equation is described to estimate the value of the liquid-phase mass-transfer coefficient of aqueous solutions of surfactants from its value for pure water. The form of the equation is obtained from Levich's theory, and it is adjusted to experiments of absorption of CO/sub 2/ in aqueous solutions of five pure surfactants. The reduction of the absorption rate is correlated with the interfacial pressure of the solution.

1986-01-01

143

Absolute absorption of ozone in the midinfrared  

Energy Technology Data Exchange (ETDEWEB)

The absolute absorption of ozone in the midinfrared has been measured relative to 253.7-nm ultraviolet absorption to an accuracy of 1% using a Bruker Fourier transform spectrometer. These new results agree with previous measurements by diode laser measurements after the latter are corrected for more recent infrared calculations and ultraviolet cross sections. They also agree with a determination based on refractive index measurements in the infrared. 16 refs., 4 figs., 3 tabs.

1992-12-20

144

AMMONIA ABSORPTION/AMMONIUM BISULFATE REGENERATION PILOT PLANT FOR FLUE GAS DESULFURIZATION  

Science.gov (United States)

The report gives results of a pilot-plant study of the ammonia absorption/ammonium bisulfate regeneration process for removing SO2 from the stack gas of coal-fired power plants. Data were developed on the effects of such operating variable in the absorption of SO2 by ammoniacal l...

145

Heat transfer problems in high temperature heat exchangers  

International Nuclear Information System (INIS)

This paper deals with construction types of high temperature heat exchangers, their circulation loops and temperature differences. Most attention is given to gas dynamics, convective heat transfer, convection and radiant heat transfer interaction in high temperature heat exchangers. The ways of heat transfer augmentation and efficient heat exchanger construction are discussed.

1986-01-01

147

Enhanced carbon dioxide removal by promoted hot potassium carbonate in a split-flow absorber  

Energy Technology Data Exchange (ETDEWEB)

In this work, a comprehensive model has been developed for the absorption of carbon dioxide into promoted hot potassium carbonate solution. The model, which is based on penetration theory, incorporates an extensive set of important reactions and takes into account the coupling between mass transfer and chemical kinetics. The penetration theory provides an appropriate absorption rate and enhancement factor for the chemical absorption. Operating data for carbon dioxide absorption into DEA-hot potassium carbonate solution has been compared with model predictions. The impact of parameters such inlet temperature of lean solution, promoter concentration, liquid split fraction, hot feed location and type of promoter on the performance of a split-flow absorber have been examined. The use of other promoters is an efficient way to enhance the carbon dioxide absorption, which has been ...

2004-07-01

148

Concentration and surface of absorption: Concepts and applications to gastrointestinal patches delivery  

British Library Electronic Table of Contents (United Kingdom)

Gastrointestinal patches represent a novel multiparticulate drug delivery system able to increase the intestinal absorption of drugs with poor bioavailability. The number of patches to administer is a critical issue since it is related to the surface and drug concentration at the absorption site. The objective of this article is to evaluate the effect of the number of administered patches on the final absorption of leuprolide, a peptide chosen as model drug, assuming complete adhesion of all the devices to the intestinal membrane. The same dose of leuprolide was encapsulated into 2, 4 and 6 patches; the resulting intestinal absorption profiles were measured with the Ussing chamber ex vivo experimental setup and compared between them. The results showed that varying the number of patches, t...

2011-01-01

149

Chemical absorption of carbon dioxide with aqueous sodium hydroxide solution spray  

Energy Technology Data Exchange (ETDEWEB)

Measurements of local mass fluxes of liquid, local number fluxes of the drop and local drop size distributions at various locations in the test column were made for wide ranges of liquid flow rates and gas flow rates. An empirical correlation for the volume mean diameter of the drop at the nozzle exit was proposed. Measurements of the rates of absorption of carbon dioxide from carbon dioxide-air mixtures with water sprays (physical absorption) and aqueous sodium hydroxide sprays (chemical absorption) were made for wide range so fluid flow rates, feed gas concentrations, and initial alkali concentrations. The observed dimensionless rates of absorption were compared with the theoretical values by assuming penetration model with second-order irreversible reaction. 11 refs., 7 figs.

1996-12-31

150

Literature and patent searches on the subject of controllable heat transfer. Final report. Literatur- und Patentrecherche zum Thema Schaltbarer Waermedurchgang. Abschlussbericht  

Energy Technology Data Exchange (ETDEWEB)

The possibility of switching the heat transfer consists of varying heat transfer surfaces and making the heat transfer temporarily more intensive. Heat tubes prove to be particularly suitable, which must be exposed to a heat carrier fluid or removed from its effect for switching the heat transfer. This report gives a survey of the possibilities of switching heat flows and for making the heat transfer more intensive. Further, the report contains a survey of patents limited to heat transfer in the fields of cooling internal combustion engines and exhaust systems. (orig.) With 17 figs., 183 refs.

1989-01-01

151

Damage process and luminescent characteristics in silica glasses under ion irradiation  

International Nuclear Information System (INIS)

Full text of publication follows: Understanding the dynamic irradiation effects on silica glasses is important for developing the diagnostic systems used in fusion and fission environments. While fundamental defects having an un-pared electron such as the E' center have been extensively studied, the neutral oxygen deficiency defects have been insufficiently clarified for lack of the detection methods. The ion induced luminescence is one of the probes that can be used to detect non-paramagnetic defects, and to observe creation and annihilation behavior dynamically. In the present study, we examined the characteristics of the ion induced luminescence such as energy, fluence flux and temperature dependence of the luminescence efficiency to analyze damage process quantitatively. Samples of SiO2 glasses were commercially available fused and synthesized silica glasses, produced by Toshiba Ceramics, Co. Ltd.. A thin films of SiO2 deposited on a Si wafer was used to determine the luminescence ...

2007-12-10

152

Relative correlation of Jet-REMPI monitoring with adsorption tube sampling followed by TDS-CIS-GC/MS  

Energy Technology Data Exchange (ETDEWEB)

During earlier work rapid and highly sensitive Jet-REMPI (resonance-enhanced multiphoton ionization) mass spectrometry was applied for monitoring the effluent from thermal treatment of a filter dust during a de novo test under laboratory conditions. The sample, from ESP-Field 2 of an iron ore sintering plant, was already loaded with dioxins ({sigma}PCDD/F = 132 ng/g), their precursors (PCBz, PCPh) and other products of incomplete combustion. Heating filter dust in a temperature window 200-350 C under a flow of air results in further formation of these pollutants. As described elsewhere, on-line detection was mostly carried out using a non-selective ionization mode, to measure a wide range of compounds simultaneously. The changes of output suggest that the reaction products increase in chlorination level with time. Another explanation is that higherchlorinated compounds appear later as a consequence of lower volatility and stronger adsorption. However, due to mass ...

2004-09-15

153

Estimation of hydrogen bondings in coal utilizing FTir and differential scanning calorimetry (DSC); FTir to DSC wo mochiita sekitannai suiso ketsugo no teiryoteki hyoka no kokoromi  

Energy Technology Data Exchange (ETDEWEB)

With an objective to know coal condensation structure which has influence on coal conversion reaction, an attempt was made on quantitative evaluation of hydrogen bonding in coal. Using as test samples the VDC made from Taiheiyo coal swollen by tetralin and vacuum-dried, and its pyrolyzed char, DSC measurement and Fourier transform infrared spectroscopy (FT) were performed. An FT spectrum comparison revealed that the VDC swollen at 220{degree}C has the hydrogen bonding relaxed partly from the original coal. However, since the change is in a huge coal molecular structure restraining space, it has stopped at relaxation of the bonding energy without causing separation as far as free radicals. On the other hand, the DSC curve shows that the VDC has slower endothermic velocity than the original coal. In other words, the difference in heat absorption amounts in both materials is equivalent to the difference of enthalpy ({Delta} H) of both materials, ...

1996-10-28

154

Economical assessment of natural gas fired combined cycle power plant with CO{sub 2} capture and sequestration  

Energy Technology Data Exchange (ETDEWEB)

Norway is privileged with extensive resources of natural gas, oil and hydropower. Location of gas fired combined cycle (CC) power plants in Norway offers advantages due to the availability of natural gas from the Norwegian continental shelf and fairly low ambient temperatures, giving high fuel-to-electricity conversion efficiency. The continental shelf provides large storage capacity for CO{sub 2} in deep saline aquifers and in drained gas fields. In this paper the results of extensive work on CO{sub 2} capture carried out during the last years by Statoil in co-operation with several engineering contractors, are presented. The goal has been to develop a commercially viable concept for a combined cycle power plant including CO{sub 2} capture and sequestration. The main concept is based on CO{sub 2} capture from exhaust gas from a combined cycle power plant, using absorption by amine (MEA) solutions. The CO{sub 2} is compressed, transported by pipeline and stored in ...

2001-07-01

155

Determination of the distribution of incident solar radiation in cavity receivers with approximately real parabolic dish collectors  

Energy Technology Data Exchange (ETDEWEB)

The absorption of solar heat and the attendant thermal and mechanical loadings on the tubes of cavity receivers depend predominantly on the flux distribution of the incident solar radiation. For an axially symmetric cavity receiver with a parabolic dish collector, it is simple to determine the insolation pattern on the receiver internal surfaces if the system is ideal. In such a system the surface of the dish is perfectly parabolic (no contour flaws are present), and the sun's central ray impinges on the dish surface parallel to the focal axis (no sun tracking flaws are present). These two conditions cannot be achieved in practice, and therefore the feasible parabolic dish system is referred to as a real system although, in actual fact, it is only an approximation to any actual system. The purpose of this paper is to devise calculation principles which permit analysis of a receiver designed for ideal conditions to verify its structural ...

1990-11-01

156

A shock tube study of the CO + OH {yields} CO{sub 2} + H reaction  

Energy Technology Data Exchange (ETDEWEB)

The rate coefficient for the title reaction has been determined using mixtures of nitric acid (HNO{sub 3}), carbon monoxide (CO), and argon in incident shock wave experiments. Upon shock heating, the nitric acid rapidly decomposes into OH and NO{sub 2}. The OH subsequently reacts predominantly via the title reaction. Quantitative OH time histories were obtained by continuous-wave (cw) narrow-linewidth UV laser absorption of the R{sub 1}(5) line of the A{sup 2}{Sigma}{sup +} {l_arrow} X{sup 2}{Pi}{sub i} (0,0) transition at 32,606.56 cm{sup {minus}1} (vacuum). In some experiments, helium was added to the reactant mixture to examine CO vibrational excitation effects on the rate coefficient determination. It was found that the rate of excited CO (v = 1) with OH is less than the rate of ground-state CO (v = 0) with OH, which is in agreement with previous state-dependent work. The experiments were conducted over the temperature range 1,090--2,370 K ...

1994-12-31

157

Cylindrical heat receiver for thermal solar-energy converters  

Energy Technology Data Exchange (ETDEWEB)

Theoretical and experimental results of investigating a cylindrical heat receiver with secondary reflectors are presented. One important element of solar thermal power plants (STPP) is the heat receiver. Several forms of heat receiver exist; the main form is the heat receiver of cavity form (including cylindrical, rectangular, and cubic heat receivers with a noncircular aperture). The linear dimension of such heat receivers is equal to, or larger than, the theoretical diameter of the concentrator focal spot.

1984-01-01

158

Advances in enhanced heat transfer: 1987  

Energy Technology Data Exchange (ETDEWEB)

This book contains nine selections. Some of the titles are: High Heat-Flux, Forced-Convection Heat Transfer for Tubes with Twisted-Tape Inserts; Heat Transfer Augmentation by Interrupted Surfaces - Experimental Consideration; Turbulent Flow Heat Transfer from Externally Roughened Tubes in Axial Flow in Concentric Pipe Heat Exchangers; and Heat Transfer Enhancement of Turbulent Flow in Pipes with an Internal Circular Rib.

1987-01-01

159

Advances in enhanced heat transfer: 1987  

International Nuclear Information System (INIS)

This book contains nine selections. Some of the titles are: High Heat-Flux, Forced-Convection Heat Transfer for Tubes with Twisted-Tape Inserts; Heat Transfer Augmentation by Interrupted Surfaces - Experimental Consideration; Turbulent Flow Heat Transfer from Externally Roughened Tubes in Axial Flow in Concentric Pipe Heat Exchangers; and Heat Transfer Enhancement of Turbulent Flow in Pipes with an Internal Circular Rib.

1987-08-09

160

Emergency core cooling device for a reactor  

International Nuclear Information System (INIS)

Purpose : To obtain an emergency core cooling device in a FBR type reactor by utilizing heat pipes which are not actuated at usual operation condition but actuated reliably upon emergency. Constitution : A system for injecting heat medium into heat pipes is provided. By injecting the heat medium into the heat pipes upon emergency to actuate the heat pipes, the reactor core is cooled. During normal reactor operation, the inside of the heat pipes is evacuated from a vacuum pump and no heat medium is filled therein, whereby unnecessary heat loss during the normal operation can be prevented. (Ikeda, J.).

1982-01-24

161

Optimal thermodynamic heat transfer  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a set of heuristics useful for optimal design of heat-exchange networks and integrated heat and power systems. These heuristics consolidate other approaches reported in the literature in a formalism useful for design purposes.

1989-06-01

162

Numerical simulation of fluid flow and heat transfer in a concentric tube heat exchanger  

International Nuclear Information System (INIS)

In this paper, numerical simulation of a concentric tube heat exchanger is presented to determine the convective heat transfer coefficient and friction factor in a smooth tube. Increasing the convective heat transfer coefficient can increase heat transfer rate in a concentric tube heat exchanger from a given tubular surface area. This can be achieved by using heat transfer augmentation devices. This work constitutes the initial phase of the numerical simulation of heat transfer from tubes employing augmentation devices, such as twisted tapes, wire-coil inserts, for heat transfer enhancement. A computational fluid dynamics (CFD) simulation tool was developed with CFX software and the results obtained from the simulations are validated with the empirical correlations for a smooth tube heat exchanger. ...

2003-05-28

163

Conjugate Heat Transfer Predictions of a Combustor ...  

Science.gov (United States)

... To maximise heat transfer rates, many heatshield designs make use of heat transfer augmentation devices such as large numbers of pin-fin ...

2003-03-01

164

Augmentation of heat and mass transfer  

Energy Technology Data Exchange (ETDEWEB)

This is the first text and reference book to be devoted completely to the very important and timely subject of heat transfer augmentation. This book is of equal appeal to both researchers and designers of heat transfer equipment.

1986-01-01

165

Spectral dependence of absorption photoinduced in a Bi{sub 12}TiO{sub 20} crystal by 532-nm laser pulses  

Science.gov (United States)

The spectral dependences of absorption photoinduced in a pure bismuth titanium oxide crystal by 532-nm laser pulses are studied. It is shown that optical absorption in the crystal in the range from 492 to 840 nm increases with increasing exposure. The photoinduced absorption relaxes in the dark for more than 60 hours. A model of photoinduced absorption is proposed which assumes the population of two trap centres with the normal energy distribution law for the concentrations of electrons photoexcited from donors to the conduction band. This model well describes the spectral dependences of photoinduced absorption by using the average ionisation energies of the traps E{sub 1} = 1.60 eV and E{sub 2} = 2.57 eV. The model is used to estimate the increase in the photorefractive sensitivity of a bismuth titanium oxide crystal in the near IR region, which was earlier observed after exposing ...

2007-11-30

166

Comparative study of solvent properties for carbon dioxide absorption  

Energy Technology Data Exchange (ETDEWEB)

Several inexpensive and non-toxic solvents with low vapour pressures were investigated for their suitability as alternative solvents for the absorption of carbon dioxide from flue gas. The solvents include poly(ethylene glycol)s, poly(ethylene glycol) ethers, poly(ethylenimine) and glycerol-based substances. Solvent properties such as thermal stability, solubility of carbon dioxide and selectivity over nitrogen were investigated in a systematic study using a thermogravimetric analyser. Absorption results are reported for pure carbon dioxide and nitrogen as well as a mixture of both gases. Desorption and long-term sorption behaviour are also discussed. Glycerol and poly(ethylene glycol)s show a high solubility of carbon dioxide. Due to the high viscosity of the solvent, carbon dioxide absorption in poly(ethylenimine) is very slow in spite of the presence of favourable amine groups. PEG 300 was found to be the best solvent in ...

2010-07-01

167

Temperature measurements via narrow line laser absorption of carbon dioxide  

Energy Technology Data Exchange (ETDEWEB)

Theoretical development for temperature measurements via narrow line, infrared absorption of carbon dioxide (CO{sub 2}) is presented. The proposed technique is based on rapid-scanning of two adjacent absorption line shapes. Spectroscopic considerations for sensitivity to temperature measurements are discussed. Several line pairs are evaluated, and the R(58) and R(60) transitions of the (00{sup 0}1){l_arrow}(00{sup 0}0) band are suggested for use in high temperature measurements for combustion systems.

1996-12-31

168

Enhancement of the absorption of CO{sub 2} in alkaline buffer solutions: Joint action of two enhancers  

Energy Technology Data Exchange (ETDEWEB)

The authors measured the absorption of CO{sub 2} in alkaline 0.5 M/0.5 M sodium carbonate/bicarbonate buffers containing either saccharose and sodium arsenite or saccharose and formaldehyde. Absorption enhancement increased upon increasing the concentration of either of the catalysts, but the joint action of the two was always less than the sum of their individual effects, the difference being a function of the acidities and concentrations of the catalysts and the pH of the carbonate/bicarbonate buffer solution

1999-05-01

169

Computational Chemistry Study of Solvents for Carbon Dioxide Absorption  

Energy Technology Data Exchange (ETDEWEB)

Absorption with aqueous amine solvents is at present the most viable technology for CO{sub 2} capture. While this is a proven technology, efforts are ongoing to improve it in order to make it a more attractive technology for large scale use to reduce CO{sub 2} emissions. Finding solvents with better properties is one approach to improving the technology. In this thesis methods in computational chemistry are used to improve the understanding of the chemistry of CO{sub 2} absorption in amine-water systems. The work is also intended to provide models that can be used to predict the performance of new solvents. Such predictive models are intended to facilitate the screening for new solvents

2005-08-15

170

Anisotropic optical absorption in quantum well wires induced by high-frequency laser fields  

British Library Electronic Table of Contents (United Kingdom)

The subband structure and optical properties of a cylindrical quantum well wire under intense non-resonant laser field are investigated by taking into account the correct dressing effect for the confinement potential. The energy levels and wave functions are calculated within the effective mass- approximation using a finite element method. It is found that the absorption coefficient and the saturation intensity are strongly affected by the laser amplitude and frequency as well as by the incident light polarization. As a key result, a large anisotropy in the linear and nonlinear optical absorptions for very intense laser field is predicted. These effects can be useful for the design of polarization sensitive devices.

2011-01-01

171

Thio and Seleno Rhodamine Derivatives as Reversal Agents ...  

Science.gov (United States)

... Values of absorption maxima, X.nax, and associated molar extinction coefficients, c, as well as values of the n-octanol/water partition coefficient( ...

2005-09-01

173

Simulation of carbon dioxide absorption by sodium hydroxide solution in a packed bed and studying the effect of operating parameters on absorption  

International Nuclear Information System (INIS)

Available in abstract form only. Full text of publication follows: In this study. simulation of carbon dioxide absorption by Sodium Hydroxide solution in a packed bed has been investigated. At first, mass and energy balances were applied around a differential height of the bed. So, the governing equations were obtained. Surface renewal theory by Danckwerts was used to represent the mass transfer operation Finally, by changing the operating parameters like solvent temperature, inlet gas composition pressure and height of the bed, the effect of these parameters on the absorption and the composition of carbon dioxide in exit stream have been investigated. (authors)

2007-09-02

174

Self-organization and electrical properties of Head-to-Tail poly(3-hexylthiophene) in Langmuir-Blodgett films  

Energy Technology Data Exchange (ETDEWEB)

The conductive ultra thin films were fabricated from mixed monolayers containing stearic acid and Head-to-Tail poly(3-alkylthiophene). These films exhibited well-defined layered structures as determined by optical absorption and X-ray diffraction measurements. The UV-Vis absorption spectra of these films showed lower energy absorption shifts of 48 nm from that of the random poly(3-alkylthiophene)/stearic acid LB films. The blue shift of absorption maximum of the LB film is attributed to the increase of {pi}-conjugation length caused by no steric hindrance of alkyl side chains. The conductivity of the Head-to-Tail poly(3-hexylthiophene)/stearic acid LB films was greatly improved in the range of 67-100 S/cm. (orig.)

1997-01-01

175

Optimization techniques for parameter estimations: case studies in CO{sub 2} separation processes  

Energy Technology Data Exchange (ETDEWEB)

Application of an optimization technique to extract the non-ideal parameters of gas absorption with chemical reactions process was described. The gas absorption was modeled using mass transfer theory to represent the realistic behaviors of an absorber. The model was a highly non-linear iterative model which correlated the overall rate of absorption as the function of unknown non-ideal parameters, including the physical liquid mass transfer coefficient and the wetted interfacial area of of packings. The optimization program was developed to minimize the sum of squares of relative errors between the model predictions and the experimental data. Four sets of experimental data (case studies) with different operating conditions were used for extracting parameters. Comparisons between predicted and experimental measured overall absorption rate were in good agreement, average absolute value of relative errors ...

1995-12-31

176

New possibilities of intensifying absorption of carbon dioxide and other acid gases  

Energy Technology Data Exchange (ETDEWEB)

Comparatively evaluates methods for removal of carbon dioxide from waste gases emitted from industrial plants. The evaluations concentrate on carbon dioxide absorption by water solutions of alkalis and amines. The Hindered Amines Process, developed by Exxon in the USA, is analyzed. Chemical reactions of carbon dioxide absorption in solutions with hindered amines are evaluated. The following US patents which protect processes for carbon dioxide absorption by means of hindered amines are evaluated: No. 4,112,052, No. 4,101,633, No. 4,112,051, No. 4,100,257, No. 4,112,050, No. 4,094,957. Efficiency of carbon dioxide removal by each of the processes is pointed out. 12 refs.

1992-11-01

177

N94- 31026 - NASA Technical Report Server (NTRS)  

Science.gov (United States)

in early 1992 from Lord Corporation, were also found. For both the reflective and absorptive polyurethanes, the fresh paint fluoresces significantly ...

178

Hybrid Composites Made from Oil Palm Empty Fruit Bunches/Jute Fibres: Water Absorption, Thickness Swelling and Density Behaviours  

British Library Electronic Table of Contents (United Kingdom)

In this research, hybrid composite materials were prepared from combination of oil palm Empty fruit bunches (EFB) fibre and jute fibre as reinforcement, epoxy as polymer matrix. This study intended to investigate the effect of jute fiber hybridization and different layering pattern on the physical properties of oil palm EFB-Epoxy composites. Water absorption and thickness swelling test reveal that hybrid composite shows a moderate water absorption which is 11.20% for hybrid EFB/Jute/EFB composite and 6.08% for hybrid Jute/EFB/Jute composite. The thickness swelling and water absorption of the hybrid composites slightly increased as the layering pattern of hybrid composites changed. Hybrid composites are more water resistance and dimensional stable compare to the pure EFB composites. This is...

2011-01-01

179

Fixation of CO_2 and export of photosynthate by the carpel in Pisum sativum  

International Nuclear Information System (INIS)

... School of Plant Biology. v. 23(2) p. 316-322. carbon dioxide absorption carbon

1970-01-01

180

Experiments toward medical management of radionuclides in the gut: effect of deferoxamine on "2"3"8Pu(NO_3)_4 absorption from rat gut  

International Nuclear Information System (INIS)

Deferoxamine (DFA) (250 mg/kg), orally administered to rats, decreased Pu absorption from orally administered "2"3"8Pu(NO_3)_4 by about 1/3. The calcium salt of diethylenetriaminepentaacetic acid (Ca-DTPA), given orally 5 to 10 min after the Pu, increased absorption about four times. DFA given 10 min before the DTPA decreased the effect of the latter by a factor of two. Deferoxamine administration prior to inhalation treatment of man with DTPA may be one way to decrease possible DTPA-enhanced gut absorption of Pu.

1977-05-01

181

Electronic properties of low temperature microcrystalline silicon carbide prepared by Hot Wire CVD  

Energy Technology Data Exchange (ETDEWEB)

Microcrystalline silicon carbide ({mu}c-SiC) was prepared at low substrate temperatures using Hot Wire chemical vapor deposition (HWCVD). High crystalline volume fractions were achieved at high hydrogen dilution and high deposition pressure. Without intentional doping, such material shows high dark conductivity and high optical absorption below the band gap. The material prepared at low deposition pressure or low hydrogen dilution, on the other hand, shows much lower conductivity and sub-gap absorption, but high spin densities up to 5 x 10{sup 19} cm{sup -3}. This high absorption can be attributed to free carriers, different to {mu}c-Si:H where a correlation between the sub-gap absorption and the spin density is observed.

2008-01-15

183

Effect of vitamin D on the intestinal absorption of 203Pb and 47Ca in chicks  

Energy Technology Data Exchange (ETDEWEB)

The transfer of 203Pb and/or 47Ca across the intestinal epithelium of the chick was investigated, with emphasis given to the functional role of cholecalciferol (vitamin D-3). 203Pb, after introduction in the intestinal lumen, is rapidly accumulated by the intestinal tissue, and only a fraction of 203Pb is translocated parenterally (absorbed). Cholecalciferol did not significantly affect the accumulation of 203Pb by intestinal tissue but did accelerate 203Pb movement across the basal-lateral membrane. In contrast, cholecalciferol both decreased 47Ca tissue levels and increased 47Ca absorption. In rachitic chicks, the rate of absorption of 203Pb was greater in the distal than in the proximal segments of the intestine; after cholecalciferol repletion, the degree of absorption in al segments was similar, indicting the order of cholecalciferol effectiveness as duodenum greater than or equal to jejunum greater than ileum. An ...

1982-03-01

184

Effect of vitamin D on the intestinal absorption of /sup 203/Pb and /sup 47/Ca in chicks  

Energy Technology Data Exchange (ETDEWEB)

The transfer of /sup 203/Pb and/or /sup 47/Ca across the intestinal epithelium of the chick was investigated, with emphasis given to the functional role of cholecalciferol (vitamin D-3). /sup 203/Pb, after introduction in the intestinal lumen, is rapidly accumulated by the intestinal tissue, and only a fraction of /sup 203/ Pb is translocated parenterally (absorbed). Cholecalciferol did not significantly affect the accumulation of /sup 203/Pb by intestinal tissue but did accelerate /sup 203/Pb movement across the basal-lateral membrane. In contrast, cholecalciferol both decreased /sup 47/Ca tissue levels and increased /sup 47/Ca absorption. In rachitic chicks, the rate of absorption of /sup 203/Pb was greater in the distal than in the proximal segments of the intestine; after cholecalciferol repletion, the degree of absorption in all segments was similar, indicating the order of cholecalciferol effectiveness as duodenum ...

1982-03-01

186

Carbon dioxide postcombustion capture: a novel screening study of the carbon dioxide absorption performance of 76 amines  

Energy Technology Data Exchange (ETDEWEB)

The significant and rapid reduction of greenhouse gas emissions is recognized as necessary to mitigate the potential climate effects from global warming. The postcombustion capture (PCC) and storage of carbon dioxide (CO{sub 2}) produced from the use of fossil fuels for electricity generation is a key technology needed to achieve these reductions. The most mature technology for CO{sub 2} capture is reversible chemical absorption into an aqueous amine solution. In this study the results from measurements of the CO{sub 2} absorption capacity of aqueous amine solutions for 76 different amines are presented. Measurements were made using both a novel isothermal gravimetric analysis (IGA) method and a traditional absorption apparatus. Seven amines, consisting of one primary, three secondary, and three tertiary amines, were identified as exhibiting outstanding absorption capacities. Most have a number of ...

2009-08-15

187

Bioavailability of copper to rats from various foodstuffs and in the presence of different carbohydrates  

Energy Technology Data Exchange (ETDEWEB)

Copper bioavailability was studied in rats using an extrinsic Cu label. Copper absorption from sunflower seeds (46%), peanuts (41%), cooked shrimp (50%), and cooked beef (40%) was as good or better than copper sulfate (46%). Copper from plant foods (sunflower seeds, garbanzo beans, peanuts) was absorbed equally as well as copper from animal foods (beef, shrimp, chicken liver), 39 +/- 7% vs 43 +/- 7%, P greater than 0.05. There was no significant difference in percentage Cu absorption between intrinsically labeled chicken liver and extrinsically labeled chicken liver. In a second experiment, Cu absorption was measured in the presence of glucose, fructose, sucrose, or cornstarch. There were no significant differences in Cu absorption due to different carbohydrates in a single meal.

1988-01-01

188

Airborne minerals and related aerosol particles: Effects on climate and the environment  

UK PubMed Central (United Kingdom)

Aerosol particles are ubiquitous in the troposphere and exert an important influence on global climate and the environment. They affect climate through scattering, transmission, and absorption of...Full Text Available

1999-03-30

189

Absorption of carbon dioxide in waste tanks  

International Nuclear Information System (INIS)

Air flow rates and carbon dioxide concentrations of air entering and exiting eight H-Area waste tanks were monitored for a period of one year. The average instanteous concentration of carbon dioxide in air is within the range reported offsite, and therefore is not affect by operation of the coal-fired power plant adjacent to the tank farm. Waste solutions in each of the tanks were observed to be continuously absorbing carbon dioxide. The rate of absorption of carbon dioxide decreased linearly with the pH of the solution. Personnel exposure associated with the routine sampling and analysis of radioactive wastes stored at SRP to determine the levels of corrosion inhibitors in solution could be reduced by monitoring the absorption of carbon dioxide and using the relationship between pH and carbon dioxide absorption to determine the free hydroxide concentration in solution.

1987-09-01

190

Absorption of CO/sub 2/ in aqueous solutions of mixtures of alkanolamines  

Energy Technology Data Exchange (ETDEWEB)

The bulk removal of CO/sub 2/ from industrial gases is a frequently applied process in the field of gas-treating. Usually chemical solvents are used in order to increase both the solvent-loading capacity and the absorption rate. These solvents often are aqueous solutions of alkanolamines. The loaded-liquid is regenerated at high temperatures with the aid steam. In the present study absorption rates are experimentally determined in various mixtures of amines over a wide range of concentrations. Simultaneously, a model was developed for the description of mass transfer accompanied by parallel reversible chemical reactions. The equations of this mass transfer model could not be solved analytically and therefore numerical techniques were used to obtain an exact description of this process. This model also includes the asymptotic situations of homogeneous catalysts and shuttle mechanism for which in the literature several approximate solutions have ...

1988-01-01

194

Municipal Heat Wave Response Plans  

UK PubMed Central (United Kingdom)

Approximately 400 people die from extreme heat each year in the United States, and the risk of heat waves may increase as a result of global climate change. Despite the risk of heat-related morbidity...Full Text Available

2004-09-01

195

Mechanisms of heat transfer augmentaiton around the stagnation point of an impinging air jet laden with solid particles. Report 1. ; Evaluation procedure of heat transfer augmentaion due to unsteady heat conduction between laden particles and heat transfer surface. Koki niso shototsu funryu no yodomiten kinbo ni okeru dennetsu sokushin kiko. 1. ; Ryushi eno chokusetsu sesshoku netsuido ni yoru dennetsu sokushin koka no bunri hoho  

Energy Technology Data Exchange (ETDEWEB)

Several heat transfer augmentation mechanisms contribute to the heat transfer augmentation around the stagnation point in the gas-solid two-phase impinging jet flow. Among those contributions, that of heat exchange was numerically analyzed and characteristically elucidated by the unsteady direct contact heat conduction at the time of impingement between the laden particles and heat transfer surface. In other words, if the contact time is short between the particles and heat transfer surface, the former is heated by heat stored in the latter as a heat capacity. In such a region, the heat quantity to be transferred to the particles changes by not only the thermal property value (heat capacity multiplied by heat conduction coefficient) of ...

1991-05-25

196

Heat transfer. Fundamentals. 5. rev. ed.  

International Nuclear Information System (INIS)

This textbook contains the following main topics: Heat conductivity, convection, condensation and evaporation, radiation heat transfer and heat exchangers. It includes the physical foundations for all these aspects and many examples. (orig.)

199

ASME proceedings of the 31. national heat transfer conference: Volume 2. HTD-Volume 324  

Energy Technology Data Exchange (ETDEWEB)

This volume is divided into the following sections: (1) fundamentals of convection heat transfer; (2) fundamentals of heat transfer with impinging jets; and (3) fundamentals of heat transfer augmentation. Separate abstracts were prepared for most papers in this volume.

1996-12-31

200

The onset conditions of enhancement of ice accumulation associated with heat-conducting plates located perpendicularly to heat-transfer surfaces; Part 1: Analysis for still water  

Energy Technology Data Exchange (ETDEWEB)

An analytical study of the ice-formation process associated with heat-conducting plates located perpendicularly to isothermally heated and cooled surfaces with some clearance is presented. It is proposed that the onset conditions, which describe whether the ice-volume fraction in a steady state is greater than or less than that without heat-conducting plates, are defined by the dimensionless distances between the heated/cooled walls and the heat-conducting plates. It is shown that the onset conditions are dependent on the pitch and the thickness of the heat-conducting plates and are less dependent on the thermal conductivity of the plates.

1994-07-01

201

The Effect of the Temperature to Which the Material is Heated ...  

Science.gov (United States)

... The Effect of the Temperature to Which the Material is Heated on the Process of Formation of Intermetallic Compounds in Magnetic Pulse Welding,. ...

1980-09-01

202

SPECIAL EDDY CURRENT PROBES FOR HEAT ...  

Science.gov (United States)

... Accession Number : ADD326926. Title : SPECIAL EDDY CURRENT PROBES FOR HEAT EXCHANGER INSPECTION. Corporate Author : ...

1986-11-01

204

Development of a geothermal heat pump. Final report  

Energy Technology Data Exchange (ETDEWEB)

In the development of a geothermal heat pump a water source heat pump was connected to a 1-1/2'' water line, 2200' long, buried in an endless loop 10' deep. The system is closed, circulating the same water continuously through the heat pump back to the field again. This water line 10' deep is the geothermal heat source. No matter how cold the air temperature gets on a winter day the water temperature to the heat pump will always be above 45/sup 0/F. This system has efficiently heated our house the past year using no supplemental heat.

1981-11-02

205

Heat transfer augmentation in rod bundles near grid spacers  

International Nuclear Information System (INIS)

Heat transfer augmentation by straight grid spacers in rod bundles is studied for single phase flow and for post critical heat flux dispersed flow. The heat transfer effect of swirling grid spacers in single phase flow is also examined. Governing heat transfer mechanisms are analyzed, and predictive formulations are established. For single phase flow, the local heat transfer at a straight spacer and at its upstream or downstream locations are treated separately. 18 refs.

1980-01-01

206

Geothermal heat-pump systems of heat supply  

International Nuclear Information System (INIS)

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

2004-06-01

207

Air-side flow and heat transfer in compact heat exchangers: A discussion of enhancement mechanisms  

Energy Technology Data Exchange (ETDEWEB)

The behavior of air flows in complex heat exchanger passages is reviewed with a focus on the heat transfer effects of boundary-layer development, turbulence, spanwise and streamwise vortices, and wake management. Each of these flow features is discussed for the plain, wavy, and interrupted passages found in contemporary compact heat exchanger designs. Results from the literature are used to help explain the role of these mechanisms in heat transfer enhancement strategies.

1998-10-01

208

Binary heat pump system. Binary heat pump system  

Energy Technology Data Exchange (ETDEWEB)

This technical report describes an outline, features, total energy efficiency, and specifications of binary heat pump system. A closed circuit distributed water heat source heat pump method is employed in the binary heat pump system. Since the circulating water, which is adjusted at a constant temperature, is used as the heat source of the indoor unit, a stable performance can be obtained regardless of outside atmospheric temperature. The binary heat pump system is mainly composed of a center heat pump unit, indoor heat pump unit, heat source water pipes, and circulating pump. The center heat pump unit and the indoor heat pump unit are connected with each other by the heat source water, and each unit can be operated independently. This ...

1993-11-30

209

Tracing Cadmium from Culture to Spikelet: Noninvasive Imaging and Quantitative Characterization of Absorption, Transport, and Accumulation of Cadmium in an Intact Rice Plant1[W][OA]  

UK PubMed Central (United Kingdom)

We characterized the absorption and short-term translocation of cadmium (Cd) in rice (Oryza sativa ‘Nipponbare’) quantitatively using serial images observed with a positron-emitting...Full Text Available

2010-04-01

210

Sustainable managment of the weaner pig through nutrition  

Environmental Research Database

DescriptionIn young pigs the post-weaning period is generally characterised by a marked reduction in voluntary feed intake, poor growth and development, and diarrhoea. The associated reduction in digestive and absorptive capacity of the gastrointestinal tract decreases the overall efficiency of nutrient capture and utilisation, thereby causing an increase in nutrient loading to the environment. The reduction in digestive and absorptive efficiency after weaning has implications for lifetime performance be [continued...

2006-01-31

211

Radioanalytical chemistry. Vol. 2  

International Nuclear Information System (INIS)

This volume of the monograph covers the following topics: activation analysis, non-activation interaction analysis (elastic scattering of charged particles, absorption and backscattering of beta radiation and photons, radionuclide X-ray fluorescence analysis, thermalization, scattering and absorption of neutrons, use of ionization caused by nuclear radiation, use of ionization by alpha or beta radiation for the measurement of pressure, density and flow rate of gases), and automation in radioanalytical chemistry. (P.A.).

1989-01-01

212

Quality engineering and control. Annual progress report, January-December 1981  

International Nuclear Information System (INIS)

Brief summaries are given of research carried out in the following areas: absorption spectroscopy of titanium, niobium, and molybdenum in uranium alloys; atomic absorption spectroscopy of selenium in stainless steel, computer program improvements for spectrophotometer control, and detection of beryllium in stack gases; electrolysis for inactivation of bacteria in cooling-tower water; improved solvent analysis by gas chromatography; sequential radionuclide separation for various sample matrices; progress on an electron microprobe analyzer; and miscellaneous projects.

213

Method of preparation of crystal borophosphate with zeolite structure. Sposob polucheniya kristallicheskogo borofosfata tseolitnoj struktury  

Energy Technology Data Exchange (ETDEWEB)

Hydrothermal method for preparing crystal borophosphate with zeolite structure is suggested. To increase absorption capacity and thermal stability of final product, aluminium hydroxide sol, ethylenediamine and ethyl acetate are added to the mixture of crystal boric and concentrated phosphoric acids. Thermal stability of the specimens prepared constitutes 880-950 deg, water absorption capacity is within the limits of 0.30-0.32 cmT/g. 1 table.

1984-12-24

214

Kinetics of carbon dioxide absorption in solutions of methyldiethanolamine  

Energy Technology Data Exchange (ETDEWEB)

The kinetics of the reaction of carbon dioxide in MDEA solutions were studied both experimentally and theoretically. It is concluded that MDEA acts as a homogeneous catalyst for CO/sub 2/ hydrolysis, and as a result the rate of absorption in aqueous MDEA solutions is significantly larger than one would calculate by simply taking into account the alkalinity of the reaction. A possible zwitterion mechanism is proposed for this reaction. The minor effect of ionic strength were also studied with the presence of other ions. 19 references, 6 figures.

1985-01-01

215

Estimation of gamma-absorption method for measurement of layers thickness in multi-layers articles  

International Nuclear Information System (INIS)

Certain problems of gamma-absorption method of measuring the thickness of layers in multi-layer items are analyzed. Two examples of solving the above-mentioned problems have been considered. One of them deals with a two-layer item, its integral thickness being known or measured in advance, the second example is referred to a two-layer item with unknown integral value

216

Electrochemical oxidation of curium(III) in potassium carbonate solution  

International Nuclear Information System (INIS)

During electrolysis of a "2"4"8Cm(III) solution in 2M K_2CO_3 at pH=13, partial oxidation of curium to a higher oxidation state, probably Cm(IV), was observed. The absorption spectra of Cm(III) and Cm(IV) in K_2CO_3 solution were recorded and the molar extinction coefficients of main absorption bands of curium were evaluated. (author).

1986-11-01

217

Effect of dietary and synthetic chelating agents on the intestinal absorption of lead. [Rats  

Energy Technology Data Exchange (ETDEWEB)

The effect of a number of dietary and synthetic chelating agents on the intestinal absorption of lead has been examined using the everted sac preparation and the tracer isotope /sup 203/Pb. All the agents examined increased lead transport into the serosal compartment. An explanation of the way in which these agents modify the model to describe lead transport is proposed.

1982-01-01

218

Determination of the conversion factor for infrared measurements of carbon in silicon  

Energy Technology Data Exchange (ETDEWEB)

The carbon content of silicon single crystals and polycrystals has been measured by charged particle activation analysis (CPAA) and infrared absorption. The authors obtained a linear relationship between the absorption coefficient at 605 cm/sup -1/ and the carbon content obtained by CPAA. They obtained a conversion factor of (1.00 +- 0.03) 10/sup 17//cm/sup 2/ for a 100% substitutional carbon.

1986-10-01

219

DOUBLE-SHELL TANK (DST) HYDROXIDE DEPLETION MODEL FOR CARBON DIOXIDE ABSORPTION  

International Nuclear Information System (INIS)

This document generates a supernatant hydroxide ion depletion model based on mechanistic principles. The carbon dioxide absorption mechanistic model is developed in this report. The report also benchmarks the model against historical tank supernatant hydroxide data and vapor space carbon dioxide data. A comparison of the newly generated mechanistic model with previously applied empirical hydroxide depletion equations is also performed.

2009-04-30

220

CO sub 2 absorption/desorption in mixtures of methyldiethanolamine with monoethanolamine or diethanolamine  

Energy Technology Data Exchange (ETDEWEB)

The paper presents a compilation of data and model interpretation of CO{sub 2} with mixtures of amines. The data includes both absorption and desorption conditions in the 288-313K range. The combined mass transfer/equilibrium model can effectively represent CO{sub 2} mass transfer rates for the various mixtures under a wide range of conditions.

1991-01-01

221

Absorption of 308-nm excimer laser radiation by balanced salt solution, sodium hyaluronate, and human cadaver eyes  

Energy Technology Data Exchange (ETDEWEB)

Absorption of the excimer laser radiations of 193-nm argon fluorine and 308-nm xenon chloride in balanced salt solution, sodium hyaluronate, and human cadaver eyes was measured. The absorption of these materials as considerably different for the two wavelengths; we found that 308-nm light experienced much less absorption than the 193-nm light. The extinction coefficient (k) for 308 nm was k = 0.19/cm for balanced salt solution and k = 0.22/cm for sodium hyaluronate. In contrast to this, the extinction coefficient for 193 nm was k = 140/cm for balanced salt solution and k = 540/cm for sodium hyaluronate. Two 1-day-old human phakic cadaver eyes showed complete absorption with both wavelengths. Using aphakic eyes, incomplete absorption was noted at the posterior pole with 308 nm and complete absorption was noted with 193 nm. The extinction in the anterior part of ...

1990-11-01

222

A radiant temperature numerical method for laser-plasma diagnostic using SXRSC with absorption method  

International Nuclear Information System (INIS)

An numerical method was developed for measuring radiant temperature using a set of absorption-foils coupled to soft x ray streak camera, SXRSC, in laser plasma experiments. An numerical code, SCC, was given. An x-ray intensity ratio vs temperature was calculated for Parylene, C_3H_6, Mylar and Aluminium. A suitable range of the measuring temperature was discussed to some absorber.

1990-01-01

223

A critical review of the hypothesis that climate change is caused by carbon dioxide  

Energy Technology Data Exchange (ETDEWEB)

This critical review with 28 references examines absorption and emission in the v2 band of the carbon dioxide molecule at around the 15micron wavelength. The argument for additional infrared absorption, the enhanced greenhouse effect due to increased carbon dioxide concentrations, and radiation transport and increased emissions are discussed. Experiments studying the transmission spectra of pure carbon dioxide and carbon dioxide in nitrogen, and comparing them with the results of climate modelling using the HITRAN and GEISA databases, are described.

2000-07-01

224

The Complex Interstellar Na I Absorption toward h and Chi Persei  

CERN Document Server

Recent high spatial and spectral resolution investigations of the diffuse interstellar medium (ISM) have found significant evidence for small-scale variations in the interstellar gas on scales less than or equal to 1 pc. To better understand the nature of small-scale variations in the ISM, we have used the KPNO WIYN Hydra multi-object spectrograph, which has a mapping advantage over the single-axis, single-scale limitations of studies using high proper motion stars and binary stars, to obtain moderate resolution (~12 km/s) interstellar Na I D absorption spectra of 172 stars toward the double open cluster h and Chi Persei. All of the sightlines toward the 150 stars with spectra that reveal absorption from the Perseus spiral arm show different interstellar Na I D absorption profiles in the Perseus arm gas. Additionally, we have utilized the KPNO Coude Feed spectrograph to obtain high-resolution (~3 km/s) interstellar Na I D ...

2004-01-01

225

Laboratory differential simulation design method of pressure absorbers for carbonization of phenolate solution by carbon dioxide in coal-tar processing  

Energy Technology Data Exchange (ETDEWEB)

A laboratory differential simulation method is used for the design of carbonization columns at coal-tar processing in which phenols are regenerated from phenolate solution by carbon dioxide absorption. The design method is based on integration of local absorption rates of carbon dioxide along the column. The local absorption rates into industrial phenolate mixture are measured in a laboratory model contactor for various compositions of the gas and liquid phases under the conditions that ensure the absorption rates in the laboratory absorber simulate the local rates in the industrial column. On the bases of the calculations, two-step carbonization columns were designed for 30000 t/year of the phenolate solution treatment by carbon dioxide. The absorption proceeds at higher pressure of 500 kPa and temperatures from 50 to 65 C, pure carbon dioxide is used and toluene is added. These ...

2009-01-15

226

Electronic spectra of plutonium ions in nitric acid and in lithium nitrate solutions  

International Nuclear Information System (INIS)

The absorption spectra of plutonium ions in nitric acid have been described. There is a characteristic change in the absorption spectra of Pu v in lithium nitrate solutions. In 2 M-lithium nitrate a new peak at 969 nm and high absorption at 1200 nm are noticed. A decrease in the absorption by about 20% and the appearance of a new shoulder at 1120 nm in 6 M-lithium nitrate are found. There is no change in the spectrum in 4 M-lithium nitrate. The absorption spectra of plutonium ions in the spectral range 200 - 400 nm are interesting. All plutonium ions have an intense band in the region 250 - 260 nm as well as a less intense and rather diffuse band at 320 - 330 nm in lithium nitrate solutions the sharp band at 250 - 260 nm has disappeared. This suggests that this band is very sensitive to the environmental field. The band is probably produced by 5 F"q#-># 5 f"q"-"1 6 d transition ...

1998-05-07

227

Copper-65-absorption by men fed intrinsically and extrinsically labeled whole wheat bread  

International Nuclear Information System (INIS)

Six men were fed a diet composed of conventional foods with all bread as whole wheat bread. Intrinsically labeled "6"5Cu bread (containing 6.5 ppm Cu and 48 atom % "6"5Cu) was substituted for unlabeled bread for 3 days, and stools were collected for 24 days. Extrinsically labeled bread was then substituted for 3 days and another 24-day stool collection made. "6"5Cu excretion was measured by mass spectrometry. Mean Cu intake was 1.10 mg of Cu/day. Average Cu balance was /minus/0.06 /+-/ 0.08 mg/day. Average absorption of the intrinsic copper was 72.2 /+-/ 9.3% and of extrinsic Cu 64.2 /+-/ 5.8%. The ratio of extrinsic to intrinsic absorption was 0.906 /+-/ 0.164. Absorption of intrinsic and extrinsic tracers did not differ significantly (p > 0.05) by a paired t-test, and the ratio (E/I) was not significantly different from 1. Use of extrinsic Cu tracers to assess Cu absorption is supported by these ...

228

Alteration of the enterohepatic recirculation of bile acids in rats after exposure to ionizing radiation  

Energy Technology Data Exchange (ETDEWEB)

The aim of this work was to study acute alterations of the enterohepatic recirculation (EHR) of bile acids 3 days after an 8-Gy radiation exposure in vivo in the rat by a washout technique. Using this technique in association with HPLC analysis, the EHR of the major individual bile acids was determined in control and irradiated animals. Ex vivo ileal taurocholate absorption was also studied in Ussing chambers. Major hepatic enzyme activities involved in bile acid synthesis were also measured. Measurements of bile acid intestinal content and intestinal absorption efficiency calculation from washout showed reduced intestinal absorption with significant differences from one bile acid to another: absorption of taurocholate and tauromuricholate was decreased, whereas absorption of the more hydrophobic taurochenodeoxycholate was increased, suggesting that intestinal passive diffusion was ...

2004-02-01

229

THE DOUBLE-DEGENERATE NUCLEUS OF THE PLANETARY NEBULA TS 01: A CLOSE BINARY EVOLUTION SHOWCASE  

International Nuclear Information System (INIS)

We present a detailed investigation of SBS 1150+599A, a close binary star hosted by the planetary nebula PN G135.9+55.9 (TS 01). The nebula, located in the Galactic halo, is the most oxygen-poor known to date and is the only one known to harbor a double degenerate core. We present XMM-Newton observations of this object, which allowed the detection of the previously invisible component of the binary core, whose existence was inferred so far only from radial velocity (RV) and photometric variations. The parameters of the binary system were deduced from a wealth of information via three independent routes using the spectral energy distribution (from the infrared to X-rays), the light and RV curves, and a detailed model atmosphere fitting of the stellar absorption features of the optical/UV component. We find that the cool component must have a mass of 0.54 #+-# 0.2 M_s_u_n, an average effective temperature, T_e_f_f, of 58,000 #+-# 3000 K, a mean radius of 0.43 #+-# ...

2010-05-01

230

Analysis and optimization of the heat transfer coefficient of a finned heat exchanger submitted to natural convection; Analise e otimizacao do coeficiente de transferencia de calor de um trocador aletado submetido a conveccao natural  

Energy Technology Data Exchange (ETDEWEB)

A heat transfer (condenser) of a domestic freezer was tested in a vertical channel in order to study the influence of the chimney effect in the optimization of the heat transfer coefficient. The variation of the opening of the channel, position and the heating power of the heat exchanger in the heat transfer coefficient was considered. The influence of the surface emissivity on the heat transfer by thermal radiation was studied with the heat exchanger testes without paint and with black paint. The air velocity entering the channel was measured with a hot wire anemometer. In order to evaluate the chimney effect, the heat exchanger was testes in a open ambient. This situation simulates its operational conditions when installed on the freezer system. The variables collected in the experimental procedures was gathered in the ...

1997-07-01

231

Synthesis, characterization and optical properties of a high NIR reflecting yellow inorganic pigment: Mo"6"+ doped Y_2Ce_2O_7 as a cool colorant  

International Nuclear Information System (INIS)

Full text: Pigments possessing the ability to confer high solar reflectance have received considerable attention in recent years. The inorganic class of NIR reflective pigments are mainly metal oxides and are primarily employed in two applications: (i) visual camouflage and (ii) reducing heat build up. More than half of the solar radiation consists of near-infrared radiation (52%), the remaining being 43% visible light and 5% ultraviolet radiation. Over heating due to solar radiation negatively affects comfort in the built environment and contributes substantially to electrical consumption for air conditioning and release of green house gases. A pigment which has strong reflections in the NIR region (780-2500 nm) can be referred to as a 'cool' pigment. However, most of the NIR reflective inorganic pigments particularly yellow (eg. cadmium yellow, lead chromate, chrome titanate yellow etc.) contain toxic metals and hence their consumption is ...

2010-11-24

232

In the Loop : A look at Manitoba's geothermal heat pump industry  

International Nuclear Information System (INIS)

This booklet outlines the position of Manitoba's heat pump market with the objective of promoting the widespread use of geothermal heat pumps in the province. It makes reference to the size of the market, customer satisfaction with heat pumps, and opinion of key players in the industry regarding the heat pump market. The information in this booklet is drawn on market research and lessons learned in Europe and the United States. In October 2001, a group of key stakeholders in Manitoba's heat pump market attended an industry working meeting to address the issues of market barriers, market enablers and market hot buttons. Market barriers include the high cost of geothermal heat pumps, lack of consumer awareness, lack of consistent standards, and public perception that heat pumps are not reliable. Market enablers include the low and stable ...

233

A new method of heat transfer augmentation by means of foreign gas jet impingement in liquid bath  

International Nuclear Information System (INIS)

The authors discuss a two-phase two-component experimental system developed to study enhancement of heat transfer from a vertical chip size heater to surrounding liquid (Freon 113 or Ethanol) due to air jet impingement. Heat transfer coefficient was measured as function of jet velocity, heat flux and the distance between exit of jet tube and heated surface. The injector was placed very close to the hot surface. It was found that the heat transfer was notably enhanced with foreign gas impingement, especially in the cases of small temperature differences between wall and coolant. In fact for higher jet velocities the heat transfer coefficients tended to infinite while the temperature differences between wall and coolant were zero. The heat transfer coefficients decreased with the increasing of heat flux. High-speed camera ...

1985-10-01

234

Experimental investigation and modelling of heat capacity, heat of fusion and melting interval of rocks  

Energy Technology Data Exchange (ETDEWEB)

The heat capacity and heat of fusion were measured for a number of minerals using differential scanning calorimetry (DSC). The DSC measurements showed that the heat of fusion for the minerals is very low compared to the heat of fusion for pure crystalline phases reported elsewhere. A model for the melting behaviour of mineral materials in terms of melting interval, heat capacities and heat of fusion has been developed. The only model input is the chemical composition of the mineral material. The model was developed to be implemented in a detailed model of a cupola furnace, thus the focus for the development was not only precision but also to obtain a model that was continuous and differentiable. The model is based on several different submodels that each covers a part of the heating and melting of rocks. Each submodel is based on large ...

2003-11-28

235

Renewable energy technologies for federal facilities: Geothermal heat pump  

Energy Technology Data Exchange (ETDEWEB)

This sheet summarizes information on geothermal heat pumps (GHPs), which extracts heat from the ground in the winter and transfers heat to the ground in the summer. More than 200,000 GHPs are operating in US; they can reduce energy consumption and related emissions by 23 to 44% compared to air-source heat pumps. Opportunities for use of GHPs, requirements, and cost are described. Important terms are defined.

1996-05-01

236

Performance of a commercial heat pipe under operational conditions  

Energy Technology Data Exchange (ETDEWEB)

The performance of a commercial heat pipe was investigated both experimentally and theoretically. The effect of the temperature difference, the surface area ratio, and the operational conditions on the performance were studied. The heat flow rate and the vapor temperature were estimated on a ready-made commercial heat pipe. Its performance varied considerably with operational conditions. Theoretical consideration of a mathematical model and several nomographs are also presented. This work is applicable to the design and use of heat pipes in the field.

1983-04-01

237

Microwave heating: Industrial applications. (Latest citations from the NTIS bibliographic database). Published Search  

Energy Technology Data Exchange (ETDEWEB)

The bibliography contains citations concerning industrial uses and design of microwave heating equipment. Included are heating and drying of paper, industrial process heat, vulcanization, textile processing, metallurgical heat for sintering and ceramic manufacturing, food processing, and curing of polymers.(Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

1995-12-01

238

Heating and hot water: the installations; Chauffage et eau chaude: les installations  

Energy Technology Data Exchange (ETDEWEB)

This book brings recommendations and information on the choice and the operating of heating systems and domestic hot water production in order to better choose the house, to better use the heating and to preserve the environment. General notions on the different heating systems and their operating on the renewable energies used and the heating emitters offer advices for the purchase of a house. (A.L.B.)

2005-07-01

239

Heat transfer  

Energy Technology Data Exchange (ETDEWEB)

Heat transfer has emerged as a leading-edge technology supporting the rapid pace of developments in science and engineering ranging from energy production to electronic cooling. Subjects covered at the 6th UK National Conference on heat transfer held at Edinburgh from 15-16 September 1999 include: convection; boiling and evaporation; condensation; numerical techniques; heat exchangers; radiation and combustion; conduction; two-phase flow and heat transfer augmentation. Fifteen of the papers are abstracted here.

1999-07-01

240

Convective heat transfer in annular flow  

International Nuclear Information System (INIS)

Several aspects of heat transfer at the annular two phase flow regime are considered. Nucleate boiling is supposed to be absent. Theoretical solutions for cases of laminar and turbulent flow in the liquid film, respectively, are considered, when steam presence does not effect the heat transfer. Heat transfer in annular flows is also considered, where steam phase consists totally or partially of the so-called incondensable gas. In this case steam phase can be a considerable resistance to heat transfer.

1980-01-01

241

Radioactive lead studies in the human  

International Nuclear Information System (INIS)

The differing susceptibility of individuals to the toxic effects of chronic lead exposure has never been fully understood. As the major intake of lead in the human is from food and beverages, any variation between individuals of the quantity of lead absorbed from the gut, and of the distribution and excretion of this lead, may account for the differences in individual susceptibility. The food and beverages themselves may have an influence, and to investigate their effects on absorption, distribution and excretion of lead, experiments were performed on normal subjects using a short lived radionuclide of lead, "2"0"3Pb, and instruments generally available in Nuclear Medicine. Lead absorption between different individuals showed a wide variation when "2"0"3Pb was taken as a single dose between meals. Minerals were found to be mainly responsible for affecting absorption when one subject ingested "2"0"3Pb in control meals from ...

242

Gastrointestinal absorption of lead in chicks: involvement of the cholecalciferol endocrine system  

Energy Technology Data Exchange (ETDEWEB)

The role of dietary calcium and phosphorus in modifying the intestinal absorption of lead and also the effect of lead ingestion on the metabolism of cholecalciferol were studied in chicks. The efficiency of absorption of /sup 203/Pb and /sup 47/Ca was increased when the animals were fed a low calcium diet and treated with cholecalciferol. The synthesis of the vitamin D-induced calcium-binding protein (CaBP) was correspondingly increased. When the chicks were depleted of vitamin D and repleted with 1,25-dihydroxycholecalciferol (1,25(OH)/sub 2/D/sub 3/) as their only source of the vitamin, the absorption of both /sup 47/Ca and /sup 203/Pb was unaffected by dietary calcium levels, and no change in CaBP levels occurred. Low dietary intake of phosphorus resulted in an increase in /sup 47/Ca and /sup 203/Pb absorption and in CaBP synthesis when the animals were treated with cholecalciferol. However, when the ...

1984-04-01

243

Gastrointestinal absorption of lead in chicks: involvement of the cholecalciferol endocrine system  

International Nuclear Information System (INIS)

The role of dietary calcium and phosphorus in modifying the intestinal absorption of lead and also the effect of lead ingestion on the metabolism of cholecalciferol were studied in chicks. The efficiency of absorption of "2"0"3Pb and "4"7Ca was increased when the animals were fed a low calcium diet and treated with cholecalciferol. The synthesis of the vitamin D-induced calcium-binding protein (CaBP) was correspondingly increased. When the chicks were depleted of vitamin D and repleted with 1,25-dihydroxycholecalciferol [1,25(OH)_2D_3] as their only source of the vitamin, the absorption of both "4"7Ca and "2"0"3Pb was unaffected by dietary calcium levels, and no change in CaBP levels occurred. Low dietary intake of phosphorus resulted in an increase in "4"7Ca and "2"0"3Pb absorption and in CaBP synthesis when the animals were treated with cholecalciferol. However, when the birds were repleted with ...

244

Experimental determination of line strengths for selected carbon monoxide and carbon dioxide absorption lines at temperatures between 295 and 1250 K  

Energy Technology Data Exchange (ETDEWEB)

Fourier transform infrared absorption spectroscopy has been used for the determination of the line strengths of 41 CO and CO[sub 2] absorption lines at temperatures between 295 and 1250 K. The CO vibrational-rotational lines were from the [ital P] branch of the fundamental absorption band (2150--1950 cm[sup [minus]1]) while the CO[sub 2] vibrational-rotational lines were from the far wing of the [ital R] branch of the [nu][sub 3] fundamental band (2395--2380 cm[sup [minus]1]). The intensities of the lines were measured from absorption spectra recorded in a high-temperature gas cell containing known concentrations of CO/CO[sub 2]/N[sub 2] gas mixtures at atmospheric pressure. Absorption spectra were recorded through the cell with the use of a moderate-resolution Fourier transform infrared spectrometer. The absorption spectra were mathematically corrected for ...

1994-11-01

245

Experimental determination of line strengths for selected carbon monoxide and carbon dioxide absorption lines at temperatures between 295 and 1250 K  

International Nuclear Information System (INIS)

Fourier transform infrared absorption spectroscopy has been used for the determination of the line strengths of 41 CO and CO_2 absorption lines at temperatures between 295 and 1250 K. The CO vibrational-rotational lines were from the P branch of the fundamental absorption band (2150--1950 cm"-"1) while the CO_2 vibrational-rotational lines were from the far wing of the R branch of the #nu#_3 fundamental band (2395--2380 cm"-"1). The intensities of the lines were measured from absorption spectra recorded in a high-temperature gas cell containing known concentrations of CO/CO_2/N_2 gas mixtures at atmospheric pressure. Absorption spectra were recorded through the cell with the use of a moderate-resolution Fourier transform infrared spectrometer. The absorption spectra were mathematically corrected for distortions resulting from the finite resolution of the ...

246

Carbon dioxide absorption of He--Ne laser radiation at 4. 2. mu. m: characteristics of self and nitrogen broadened cases  

Energy Technology Data Exchange (ETDEWEB)

A laser resonance absorption spectrometer is used to investigate the characteristics of both self and nitrogen collision broadened carbon dioxide in resonance with He--Ne laser radiation at 4.2 ..mu..m. The absorption coefficient in these broadening conditions has contributions from the R(28) to R(34) absorption lines of the ..nu../sub 3/ CO/sub 2/ spectrum. The Fletcher-Powell optimization method is used to reduce the raw absorption data and to find the best value average collision broadening coefficient and laser emission frequency for a Lorentzian line shape model of the contributing lines. Pure carbon dioxide absorption in a pressure range of from 0.0016 atm (1.25 Torr) to 0.33 atm (250 Torr) is described well by the model with an average self broadening coefficient of 0.084 +- 0.008 cm/sup -1/ atm/sup -1/ for laser frequencies located at either 2370.591 +- 0.020 cm/sup -1/ or ...

1989-03-01

247

Tunable erbium-doped fiber ring laser for applications of infrared absorption spectroscopy  

British Library Electronic Table of Contents (United Kingdom)

We fabricate a low noise erbium-doped fiber ring laser that can be continuously tuned over 102nm by insertion of the fiber Fabry-Perot tunable filter (FFP-TF) in the ring cavity with a novel cavity structure and the optimal gain medium length. As an application of this fiber ring laser, we performed the absorption spectroscopy of acetylene (13C2H2) and hydrogen cyanide (H13C14N) and measure the absorption spectra of more than 50 transition lines of these gases with an excellent signal to noise ratio (SNR). The pressure broadening coefficients of four acetylene transition lines are obtained using this fiber ring laser and an external cavity laser diode.

2007-01-01

248

Synthesis and investigation of #pi#-conjugated azomethine self-assembled multilayers by layer-by-layer growth  

International Nuclear Information System (INIS)

Layer-by-layer formation for #pi#-conjugated azomethine multilayers bonded on substrates was investigated. The multilayers were synthesized using ethanol (EtOH) and dichloromethane (DCM) as reaction solvents. The multilayer characteristics were analyzed using UV-vis absorption spectroscopy, ellipsometric thickness, and atomic force microscopy. The absorption spectra and ellipsometric thicknesses of multilayers formed using EtOH and DCM were compared. The results indicate that EtOH is more suitable than DCM for such layer-by-layer formation. In addition, bandgaps estimated from the absorption edge of multilayers were investigated. The results indicate that the bandgap decreases as the number of benzene rings contained in the molecular chain of the multilayer increases. Also, a multilayer with four benzene rings bonded on a substrate had a bandgap close to that of a polymer with a similar chemical structure.

2010-07-01

249

Surface analysis by Fourier-transform infrared (FTIR) spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

A diffuse-reflectance capability for the Fourier transform infrared spectrometer at the Y-12 Plant Laboratory has been implemented. A sample cell with a 25 to 400/sup 0/C temperature-controlled sample stage and an ultrahigh-vacuum-to-atmospheric pressure gas-handling capability has been developed. Absorbance of light from the spectrometer beam, resulting from the beam being scattered from a powder sample, can be measured. This capability of detecting molecular species on and in powders is to be used to study chemisorption on actinide and rare-earth metals, alloys, and compounds. Cell design is described along with experiments demonstrating its performance in detecting moisture absorption on uranium oxide, moisture and carbon dioxide absorption on the lithium hydride/hydroxide system, and carbon dioxide absorption on potassium borohydride. 13 figures.

1981-08-12

250

Moessbauer spectroscopic determination of chemical state of iron in bauxite  

International Nuclear Information System (INIS)

The chemical state of iron contained in several kinds of bauxite, which are utilized as a raw material in the aluminum industry in Japan, were investigated by Moessbauer spectroscopy. The main compounds of iron were identified from the results, which showed variations of the Moessbauer absorption spectra with calcination and measuring temperature. Although the absorption intensities of the spectra differed significantly, major species identified were paramagnetic or superparamagnetic #alpha#-Fe_2O_3 in all of these bauxite samples. The superparamagnetic #alpha#-Fe_2O_3 was found mainly in the gibbsite-type bauxite, but not in the boehmite/gibbsite-type or the boehmite-type bauxite. The Moessbauer absorption spectra of red mud and its calcined products were also given. (author).

251

Luminescence and x-ray absorption measurements of persistent SrAl2O4:Eu,Dy powders: Evidence for valence state changes  

Science.gov (United States)

The development of new efficient afterglow phosphors is currently hampered by a limited understanding of the persistent luminescence mechanism. Radioluminescence (RL) and x-ray absorption measurements on the persistent phosphor SrAl2O4:Eu,Dy were combined to reveal possible valence state changes for the rare earth (co)dopants. Traps in the phosphor material are quickly filled when exposing thermally emptied SrAl2O4:Eu,Dy powder to x rays. On the same time scale a partial oxidation of Eu2+ to Eu3+ is observed by x-ray absorption near-edge spectroscopy (XANES), while for the trivalent dysprosium the valence state remains unchanged. The impact of these observations on the recently proposed models for persistent luminescence is discussed.

2011-08-01

252

Local Ce environments and their effects on optical properties of SrS phosphors  

International Nuclear Information System (INIS)

In this study, we use electron paramagnetic resonance (EPR), optical absorption, and photoluminescence (PL) spectroscopies to determine the various Ce environments in SrS phosphor materials and how these affect absorption and emission properties. As the Ce concentration is increased from 450 to 7500 ppm, the total EPR-active Ce"3"+ and optical absorption signals increase linearly with Ce concentration; by contrast, the PL intensity saturates at fairly low Ce concentrations (1000 ppm Ce). We suggest that the nonlinear behavior of the PL arises from the presence of nonradiative deexcitation pathways such as defects associated with Ce sites, or Ce endash Ce pairs. copyright 1996 American Institute of Physics.

253

Diode laser overtone spectroscopy of CO_2 at 780nm  

International Nuclear Information System (INIS)

Overtone absorption lines of "1"2C"1"6O_2 have been examined by using a tunable diode laser (TDL) spectrometer in the region around 12770cm"-"1. The spectrometer sources are commercially available double heterostructure InGaAlAs TDLs operating in the 'free-running' mode, which allowed the detection of the line positions within 0.01cm"-"1. The observed carbon dioxide absorption lines belong to the #nu#_1+5#nu#_3 ro-vibrational band with rotational quantum number J up to 48. The minimum absorbance detected by the spectrometer (#approx#5x10"-"6) permitted to observe the weakest lines having the absorption cross section of the order of #approx#1x10"-"2"7cm"2/molecule.

2005-12-01

254

Comment on "Limits on the Time Variation of the Electromagnetic Fine-Structure Constant in the Low Energy Limit from Absorption Lines in the Spectra of Distant Quasars"  

CERN Document Server

In their Letter [Phys. Rev. Lett. 92, 121302 (2004)] (also [Astron. Astrophys. 417, 853 (2004)]), Srianand et al. analysed optical spectra of heavy-element species in 23 absorption systems along background quasar sight-lines, reporting limits on relative variations in the fine-structure constant: da/a=(-0.06+/-0.06) x 10^{-5}. Here we demonstrate basic flaws in their analysis, using the same data and absorption profile fits, which led to spurious values of da/a and significantly underestimated uncertainties. We conclude that these data and fits offer no stringent test of previous evidence for a varying alpha.

2007-01-01

255

Characteristics of lanthanides in pyrochemical systems observed by electrochemical and spectrophotometric measurements  

Energy Technology Data Exchange (ETDEWEB)

As research for the chemical properties of lanthanide molecules in the dry system, electrochemical and ultraviolet-visible optical measurements on the chloride molten salt system have been conducted at Research Reactor Institute, Kyoto University. The reduction behavior of Ln(III)-Ln(0) and Ln(II) are measured on La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, and Yb by the cyclic voltammetry. The molar absorption coefficients of the f-f transition are measured by the measurement of ultraviolet-visible absorption spectra on Pr, Nd, Ho and Gd. From the comparison of the optical data between wet and dry systems, the characteristics of photon absorption are discussed in the molten salt. (H. Katsuta)

2001-12-01

256

Acid gas absorption in aqueous solutions of mixed amines  

Energy Technology Data Exchange (ETDEWEB)

A mass transfer model has been developed to describe the rate of absorption (or desorption) of H{sub 2}S and CO{sub 2} in aqueous blends of a tertiary and a secondary or a primary amine. The model is based on penetration theory, and all significant chemical reactions are incorporated in the model. The reactions are taken to be reversible, with reactions involving only a proton transfer considered to be at equilibrium. The particular amines studied in this research were methyldiethanolamine (MDEA), a tertiary amine, and diethanolamine (DEA), a secondary amine. Key physicochemical data needed in the model, such as diffusion coefficients, kinetic rate constants, and gas solubilities, were measured. Experimental absorption rates of CO{sub 2} and H{sub 2}S were measured in a model gas-liquid contacting device and were compared with model predictions. Experiments were carried out for single amine solutions (both MDEA and DEA) and for amine blends.

1996-12-31

257

Absorption of carbon dioxide at high partial pressures in 1-amino-2-propanol aqueous solution. Considerations of thermal effects  

Energy Technology Data Exchange (ETDEWEB)

In the present work, the process of carbon dioxide absorption is analyzed at high partial pressures, in aqueous solutions of 1-amino-2-propanol (monoisopropanolamine (MIPA)), in relation to the thermal effects involved. All experiments were made in a stirred-tank reactor with a plane unbroken gas-liquid interface. The variables considered were the MIPA concentration within the range 0.1--2.0 M and the temperature within the interval 288--308 K. From the results, the authors deduce that the absorption process takes place in the nonisothermal instantaneous regime and propose an equation which not only relates the experimental results of flow density with the initial concentration of amine but at the same time enables the evaluation of the rise in temperature in the gas-liquid interface.

1997-10-01

258

A new method of determining the inclination angle in interacting binaries  

CERN Document Server

We describe a method of determining the system parameters in non-eclipsing interacting binaries. We find that the extent to which an observer sees the shape of the Roche-lobe of the secondary star governs the amount of distortion of the absorption line profiles. The width and degree of asymmetry of the phase-resolved absorption line profiles show a characteristic shape, which depends primarily on the binary inclination and gravity darkening exponent. We show that, in principle, by obtaining high spectral and time resolution spectra of quiescent cataclysmic variables or low mass X-ray binaries in which the mass-losing star is visible, fitting the shape of absorption line profiles will allow one to determine not only the mass function of the binary, but also the binary inclination and hence the mass of the binary components.

1998-01-01

259

#gamma# irradiation of aqueous solutions of human hemoglobin in atmospheres of air and argon  

International Nuclear Information System (INIS)

In this study, the degrees of destruction of hemoglobin irradiated in atmospheres of air and argon were compared. Hemoglobin preparations were irradiated in the forms: oxyhemoglobin (HbO_2) deoxyhemoglobin (Hb"2"+) and methemoglobin (MetHb) applying doses of 0.5 to 5 Mrad. The degree of hemoglobin destruction was estimate on the basis of changes in the values of the absorption coefficient at the Soret band, the absorption ratio A_5_0_5/A_5_6_3 determined after conversion of irradiated preparations into MetHb, absorption coefficinets for pyridine hemochromogen obtained from irradiated preparations, and changes in parameters characterizing the hemoglobin oxygenation reaction (log p/sub 1/2/O_2 and the Hill n coefficient). The calculated oxygen enhancement ratios S were generally higher than 1 for the parameters estimated. This indicates that the presence of oxygen during irradiation enhances hemoglobin destruction.

260

Thermal energy considerations on solar cavity wall building  

Energy Technology Data Exchange (ETDEWEB)

The dwelling is equipped with solar collectors which heat the air circulating in the cavity walls and the space beneath the floors. The thermal aspects of such a building are described. Heat balance, losses, heating by the sun in different seasons are described. Different measures taken to reduce the energy losses are described.

1983-02-01

261

Recovering heat from the cupola stack  

Energy Technology Data Exchange (ETDEWEB)

A brief survey is given of some ways in which heat, which would normally be lost from a cupola furnace, is being recovered, either as hot water, steam, or electricity. Examples are provided of heat-recovery systems in Germany, Italy, and America. (author).

1986-01-01

262

Program listing for heat-pump seasonal-performance model (SPM). [CNHSPM  

Science.gov (United States)

The computer program CNHSPM is listed which predicts heat pump seasonal energy consumption (including defrost, cyclic degradation, and supplementary heat) using steady state rating point performance and binned weather data. (LEW)

1982-06-30

263

Mushy state forming of magnesium alloy making use of resistance heating  

Energy Technology Data Exchange (ETDEWEB)

Feasibility of mushy state forming of magnesium alloys making use of resistance heating was examined. Magnesium alloys, AZ31, AZ61 and AZ91, were taken up as experimental materials and cylindrical billets with a diameter of 15 mm and a height of 20 mm were used for both resistance heating and forming experiments. Input heat control was applied to the billet heating and insertion of thin discs of austenitic stainless steel with a low thermal conductivity between the billet and copper electrodes was attempted in order to improve the efficiency of the billet heating. Results were summarized as follows. (1) Resistance heating by input heat control was successful to heat the billets to their respective mushy state. (2) Insertion of the discs was very helpful in heating the billets and realized the ...

2003-07-01

264

Influence of surface heat flux ratio on heat transfer augmentation in square channels with parallel, crossed, and V-shaped angled ribs  

Science.gov (United States)

The paper investigates the effect of the wall heat flux ratio on the local heat transfer augmentation in a square channel with two opposite in-line ribbed walls for Reynolds numbers from 15,000 to 80,000. The square channel composed of 10 isolated copper sections has a length-to-hydraulic diameter ratio of 20. The rib height-to-hydraulic diameter ratio is 0.0625 and the rib pitch-to-height ratio equals 10. Six ribbed side to smooth side wall heat flux ratios are studied for four rib orientations. The results show that the ribbed side wall heat transfer augmentation increases with increasing ribbed side to smooth side wall heat flux ratios, but the reverse is true for the smooth side wall heat transfer augmentation. The average heat transfer augmentation of the ribbed side and smooth side wall decreases slightly with increasing wall ...

1992-10-01

265

Heat Transfer Augmentation in Turbulent Impinging Jets.  

Science.gov (United States)

Heating and cooling by impinging jets is widely used in various engineering applications, due to the high heat transfer rates prevailing in the vicinity of the stagnation point. The authors have been able to utilize acoustically excited turbulence for the...

1979-01-01

266

Fourth Order Accurate Discretization for the Laplace and Heat Equations on Arbitrary Domains, with Applications to the Stefan Problem.  

Science.gov (United States)

In this paper, the authors first describe a fourth order accurate finite difference discretization for both the Laplace equation and the heat equation with Dirichlet boundary conditions on irregular domains. In the case of the heat equation, they use an i...

2004-01-01

267

Environmental and yield aspects of heat provision  

International Nuclear Information System (INIS)

The advantages of district heating as an environmental-friendly and energy-saving technique are reviewed. The role of district heating as part of the Dutch national plan to reduce the emission of acidification and greenhouse gases by respectively 50 and 25 percent is clarified. 12 Tabs. (A.S.).

1994-01-01

268

Cytoplasmic heat shock granules are formed from precursor particles and are associated with a specific set of mRNAs.  

UK PubMed Central (United Kingdom)

In heat-shocked tomato cell cultures, cytoplasmic heat shock granules (HSGs) are tightly associated with a specific subset of mRNAs coding mainly for the untranslated control proteins. This messenger...Full Text Available

1989-03-01

269

?Activation of the mitogen-activated protein kinase pathways by heat shock  

UK PubMed Central (United Kingdom)

In addition to inducing new transcriptional activities that lead within a few hours to the accumulation of heat shock proteins (Hsps), heat shock activates within minutes the major signaling transduction...Full Text Available

2002-04-01

270

Thermodynamic analysis of a hybrid geothermal heat pump system  

British Library Electronic Table of Contents (United Kingdom)

A thermodynamic analysis of a hybrid geothermal heat pump system is carried out. Mass, energy, and exergy balances are applied to the system, which has a cooling tower as a heat rejection unit, and system performance is evaluated in terms of coefficient of performance and exergy efficiency. The heating coefficient of performance for the overall system is found to be 5.34, while the corresponding exergy efficiency is 63.4%. The effect of ambient temperature on the exergy destruction and exergy efficiency is investigated for the system components. The results indicate that the performance of hybrid geothermal heat pump systems is superior to air-source heat pumps.

2011-01-01

271

The study of thermal characteristics of high temperature oven for atomic spectroscopy  

International Nuclear Information System (INIS)

We present a high temperature heat oven with merits of conventional heat pipe oven and study ots thermal characteristics. The oven consists of stainless steel body and heating part of three layers of ceramic tubes. We obtained the maximum temperature of about 1350. deg. C at the center which was measured by thermocouple and infrared thermometer. And we compared the heating characteristics in the cases of external heating and no extent heating. It was applied to self diffraction experiment in the samarium gas which was one of the high melting point material.

1997-11-01

272

Steady-state thermal and hydraulic calculation of steam generator considering heat transfer tube lengths  

Energy Technology Data Exchange (ETDEWEB)

The effect of heat transfer is described from heat exchange tubes of a horizontal steam generator on the distribution of primary water to the individual tubes of the tube bundle. It is shown that in a broad interval of mass flow rates and lengths of heat exchange tubes, the simplified method of calcualtion, i.e., calculation of the distribution of primary water into heat exchange tubes neqlecting the changes of physical properties of water along the heat exchange tubes, will yield sufficiently accurate results.

1982-10-01

273

Steady-state thermal and hydraulic calculation of steam generator considering heat transfer tube lengths  

International Nuclear Information System (INIS)

The effect of heat transfer is described from heat exchange tubes of a horizontal steam generator on the distribution of primary water to the individual tubes of the tube bundle. It is shown that in a broad interval of mass flow rates and lengths of heat exchange tubes, the simplified method of calcualtion, i.e., calculation of the distribution of primary water into heat exchange tubes neqlecting the changes of physical properties of water along the heat exchange tubes, will yield sufficiently accurate results. (author).

1982-01-01

274

Perturbation solution to heat conduction in melting or solidification with heat generation  

Science.gov (United States)

The Stefan problem involving a source term is considered in this technical note. As an example, planar solidification with time-dependent heat generation in a semi-infinite plane is solved by use of a perturbation technique. The perturbation solution is validated by reducing the problem to the case without heat generation whose exact solution is available. An application to the case with constant heat generation is presented, for which a closed-form solution is obtained. The effects of heat generation and Stefan number on the evolution of solidification are examined using the perturbation solution.

2010-04-01

275

Low temperature latent heat thermal energy storage - heat storage materials  

Energy Technology Data Exchange (ETDEWEB)

Heat-of-fusion storage materials for low temperature latent heat storage in the temperature range 0-120 C are reviewed. Organic and inorganic heat storage materials classified as paraffins, fatty acids, inorganic salt hydrates and eutectic compounds are considered. The melting and freezing behavior of the various substances is investigated using the techniques of Thermal Analysis and Differential Scanning Calorimetry. The importance of thermal cycling tests for establishing the long-term stability of the storage materials is discussed. Finally, some data pertaining to the corrosion compatibility of heat-of-fusion substances with conventional materials of construction is presented.

1983-01-01

276

Geothermal heat pump applications: Industrial/commercial  

Energy Technology Data Exchange (ETDEWEB)

The fastest rate of growth in the space conditioning market has been attributed to the application of geothermal heat pumps to the industrial and commercial markets. The author reviews and provides examples of the three most popular components of a large geothermal heat pump system: geothermal earth coupling, heat pumps and heat exchangers, and building side terminals. These components are applied to three example geothermal installations: a library, an office building, and a school. Examples of energy use before and after the installation of a geothermal space conditioning system are summarized. General design and cost guidelines and comments on the use of geothermal heat pump in these and similar applications are discussed.

1999-07-01

277

Workability and Heat Treatment Characteristics of Beta ...  

Science.gov (United States)

... Accession Number : ADD135317. Title : Workability and Heat Treatment Characteristics of Beta Titanium Alloy, Ti-15V-3Cr-3Sn-3Al,. ...

1986-04-01

278

Underground Mine Water Heating and Cooling Using Geothermal Heat Pump Systems  

Energy Technology Data Exchange (ETDEWEB)

In many regions of the world, flooded mines are a potentially cost-effective option for heating and cooling using geothermal heat pump systems. For example, a single coal seam in Pennsylvania, West Virginia, and Ohio contains 5.1 x 1012 L of water. The growing volume of water discharging from this one coal seam totals 380,000 L/min, which could theoretically heat and cool 20,000 homes. Using the water stored in the mines would conservatively extend this option to an order of magnitude more sites. Based on current energy prices, geothermal heat pump systems using mine water could reduce annual costs for heating by 67% and cooling by 50% over conventional methods (natural gas or heating oil and standard air conditioning).

2006-03-01

279

To Possibility of Usage of FMW Plasma Heating Scenarios in the ICR Frequency Range in the Torsatron Reactor  

International Nuclear Information System (INIS)

The problem of fast wave plasma heating in reactor-torsatron at the ICRF range in scenarios, optimal for fusion reactor, is numerically studied.

2006-01-01

280

Subcooled Flow Boiling in a Minichannel  

British Library Electronic Table of Contents (United Kingdom)

It has been considered that dry-out occurs easily in boiling heat transfer for a small channel, a mini- or microchannel, because the channel was easily filled with coalescing vapor bubbles. In the present study, the experiments of subcooled flow boiling of water were performed under atmospheric conditions for a horizontal rectangular channel for which the size is 1 mm height and 1 mm width, with a flat heating surface of 10 mm length and 1 mm width placed on the bottom of the channel. The heating surface has a top of copper heating block and is heated by ceramic heaters. In the high heat flux region of nucleate boiling, about 70-80% of the heating surface was covered with a large coalescing bubble and the boiling reached critical heat flux as observed by high-speed video. In the beginning ...

2011-01-01

281

Rural residential application of geothermal heat pump. Progress report  

Energy Technology Data Exchange (ETDEWEB)

The installation and performance of a water source heat pump in Minnesota are discussed. The operating cost was found to be higher than expected. (MHR)

1981-07-20

282

PROCEEDINGS OF THE 1966 HEAT TRANSFER AND FLUID ...  

Science.gov (United States)

... mass of gray gas by thermal radiation; An experimental study of the turbulent wake behind a cone at M = 5; Heat transfer augmentation by steady ...

283

NASA Technical Paper 3487 ... - NASA Technical Reports Server  

Science.gov (United States)

heat transfer augmentation was found to increase with decreasing length scale but no optimum length scale was found. Heat transfer augmentation due to turbu- ...

284

Metal Foam Heat Exchangers for Heat Transfer Augmentation from a Cylinder in Cross-Flow  

British Library Electronic Table of Contents (United Kingdom)

A numerical study has been conducted to examine the heat transfer from a metal foam-wrapped solid cylinder in cross-flow. Effects of the key parameters including the free stream velocity and characteristics of metal foam such as porosity, permeability, and form drag coefficient on heat and fluid flow are examined. Being a determining factor in pressure drop and heat transfer increment, the porous layer thickness is changed systematically to observe that there is an optimum layer thickness beyond which the heat transfer does not improve while the pressure drop continues to increase. This has been verified by the application of Bejan?s Intersection of Asymptotes method. Results have been compared to those of a finned-tube heat exchanger to observe much higher heat transfer rate with reasonab...

2011-01-01

285

Long-term storage of solar heat  

Energy Technology Data Exchange (ETDEWEB)

Stochastic models for the simulation of global radiation are discussed. Thermal transients in the ground are analyzed. The performance of buried-pipe storage and a space heating system with long-term storage is described.

1981-06-01

286

Heat-transfer augmentation in rod bundles near grid spacers  

International Nuclear Information System (INIS)

Heat-transfer augmentation by straight grid spacers in rod bundles is studied for single-phase flow and for post-critical heat flux dispersed flow. The heat transfer effect of swirling grid spacers in single-phase flow is also examined. Governing heat-transfer mechanisms are analyzed, and predictive formulations are established. For single-phase flow, the local heat transfer at a straight spacer and at its upstream or downstream locations are treated separately. The effect of local velocity increasing near swirling spacer is considered. For post critical heat flux (CHF) dispersed flow, the heat transfer by thermal radiation, fin cooling, and vapor convection near the spacer are calculated. The predictions are compared with experimental data with satisfactory agreement.

1982-01-01

287

Heat transfer augmentation of mixed convection through vortex shedding from an inclined plate in a vertical channel containing heated blocks  

Energy Technology Data Exchange (ETDEWEB)

A numerical analysis is made of the unsteady flow and heat transfer characteristics of mixed convection in a vertical block-heated channel with and without installing an inclined plate above an upstream block. Parameter studies including the inclined plate angle, Reynolds number (ranging from 260 to 530), and Grashof number (in the range of 0--3,200,000) on heat transfer performance have been explored in detail. The results show that the installation of an inclined plate in the vertical block-heated channel can effectively augment the blocks` heat transfer performance in the channel. This can be applied to heat exchangers.

1998-02-06

288

Fundamental study of heat transfer augmentation of tube inside surface by cascade smooth surface-turbulence promoters  

Science.gov (United States)

Fundamental study of heat transfer augmentation of tube inside surface by cascade smooth surface-turbulence promoters

1987-03-01

289

Forced convective heat transfer in cross-corrugated solar air heaters  

Science.gov (United States)

Forced convective heat transfer in a cross-corrugated channel solar air heater has been studied experimentally using air as a working fluid. The channel was formed by two transversely positioned corrugated sheets and two flat thermally insulated side walls. One corrugated sheet was heated by a radiant heater, while the other was thermally insulated. The fluid velocity and temperature, and the wall temperature and the local heat flux across the heated corrugated sheet were measured for a variety of operating flow rates. Experimental results for the channel geometry have yielded the correlation Nu = 0.0743 (Re)[sup 0.76]. This heat-transfer coefficient is about 2.8 times that of a smooth flat channel. The experiments showed that local heat transfer rate was smaller on the valley of the corrugation than that on the peak. The ratio of the local ...

1994-11-01

290

Device for energy-saving heating of fuel in the fuel supply for an internal combustion engine  

Energy Technology Data Exchange (ETDEWEB)

The invention concerns a device for the energy-saving heating of fuel in the supply pipe to an internal combustion engine to regain energy from the fuel itself, particularly but not exclusively for a Diesel engine. A part of the quantity of heat added to the fuel between the tank and the injection nozzles is given up by excess fuel not to the tank, but to the fuel lifted upstream of the injection pump. The device is characterised by the fact that it has a heat exchanger, which absorbs heat from the fuel at the level of the injection pump or upstream of it, and takes this to the fuel above the injection pump. The heat exchanger is preferably mounted upstream of a filter and close to it. A bridging pipe, which may be integrated in the heat exchanger, permits the heat exchanger to be short-circuited depending on the fuel temperature.

1981-02-10

291

DEPLOYABLE HEAT PDPE RADUATOR - NASA Technical Report Server (NTRS)  

Science.gov (United States)

Eninger, J. E.: "Menisci Coalesence as a Mechanism for Venting Noncondensible. Gas From Heat-Pipe Arteries", AIAA Paper No. 74-748. ...

292

Analysis of Rough Wall Turbulent Heating with Application to ...  

Science.gov (United States)

... roughness. Since T u'v' and q v'"F the heat transfer augmentation is the square root of the skin friction augmentation: - 1/2 (( St - ,Cf 0 ...

1979-01-01

293

Deuterium isotope effect on molar heat capacities and apparent molar heat capacities in dilute aqueous solutions: A multi-channel heat-flow microcalorimeter study  

International Nuclear Information System (INIS)

The molar heat capacities of chloroform, dichloromethane, methanol, acetonitrile, acetone, dimethyl sulfoxide, benzene, dimethylformamide, toluene, and cyclohexane, as well as their deuterated isotopologues, were measured using a multi-channel heat conduction TAM (Thermal Activity Monitor) III microcalorimeter. In addition, the apparent molar heat capacities of some of the associated dilute aqueous solutions (0.0039 i < 0.0210) were also measured. A temperature drop method from (298.15 to 297.15) K at 0.1 MPa was employed. The corresponding heat capacities were determined from the integration of the measured heat flow. The heat capacity results are shown to be in good to very good agreement with the available literature values. In addition, good correlations were obtained for the effect of isotopic substitution on both molar heat capacity ...

2008-11-01

294

COOLOD, Steady-State Thermal Hydraulics of Research Reactors  

International Nuclear Information System (INIS)

1 - Description of program or function: The COOLOD-N2 code provides a capability for the analyses of the steady-state thermal-hydraulics of research reactors. This code is a revised version of the COOLOD-N code, and is applicable not only for research reactors in which plate-type fuel is adopted, but also for research reactors in which rod-type fuel is adopted. In the code, subroutines to calculate temperature distribution in rod-type fuel have been newly added to the COOLOD-N code. The COOLOD-N2 code can calculate fuel temperatures under both forced convection cooling mode and natural convection cooling mode. A 'Heat Transfer package' is used for calculating heat transfer coefficient, DNB heat flux etc. The 'Heat Transfer package' is a subroutine program and is especially developed for research reactors in which plate-type fuel is adopted. In case of rod-type fuel, DNB heat flux is ...

295

Urinary isotopic analysis in the UK Armed Forces: no evidence of depleted uranium absorption in combat and other personnel in Iraq  

UK PubMed Central (United Kingdom)

ObjectivesTo assess the distribution and risk factors of depleted uranium uptake in military personnel who had taken part in the invasion of Iraq in 2003.MethodsSector...Full Text Available

2007-12-01

296

Time-dependent radiolytic yields at room temperature and temperature-dependent absorption spectra of the solvated electrons in polyols  

International Nuclear Information System (INIS)

The molar extinction coefficients at the absorption maximum of the solvated electron spectrum have been evaluated to be 900, 970, and 1000 mol-1?m2 for 1,2-ethanediol (12ED), 1,2-propanediol (12PD), and 1,3-propanediol (13PD), respectively. These values are two-third or three-fourth of the value usually reported in the published report. Picosecond pulse radiolysis studies have aided in depicting the radiolytic yield of the solvated electron in these solvents as a function of time from picosecond to microsecond. The radiolytic yield in these viscous solvents is found to be strongly different from that of the water solution. The temperature dependent absorption spectra of the solvated electron in 12ED, 12PD, and 13PD have been also investigated. In all the three solvents, the optical spectra shift to the red with increasing temperature. While the shape of the spectra does not change in 13PD, a widening on the blue side of the ...

2007-02-01

297

The role of skin absorption as a route of exposure for volatile organic compounds (VOCs) in drinking water.  

UK PubMed Central (United Kingdom)

Assessments of drinking water safety rely on the assumption that ingestion represents the principal route of exposure. A review of the experimental literature revealed that skin penetration rates for...Full Text Available

1984-05-01

298

The effects of zinc deficiency on pancreatic carboxypeptidase activity and protein digestion and absorption in the rat  

UK PubMed Central (United Kingdom)

1. Proteolytic enzyme activities were examined in the pancreas of zinc-deficient and control rats. 2. No change was detected in trypsin-plus-chymotrypsin activity. 3. Carboxypeptidase activity was...Full Text Available

1967-03-01

299

The distribution of Lyman-limit absorption systems during and after reionization  

CERN Document Server

Lyman-limit absorption systems can play many important roles during and after cosmological reionization. Unfortunately, due to the prohibitively large dynamic range required, it is impossible to self-consistently include these systems in cosmological simulations. Using fast and versatile semi-numeric simulations, we systematically explore the spatial distribution of absorption systems during and following reionization. We self-calibrate the resulting number of absorbers to the mean free path (mfp) of the ionizing ultraviolet background (UVB), and present results at a given mfp and neutral hydrogen fraction. We use a simple optical depth criterion to identify the locations of absorbers. Our approach is fairly robust to uncertainties such as missing subgrid structure. Unlike at lower redshifts where the UVB is relatively uniform, at higher redshifts the fluctuations in the UVB and the HII morphology of reionization can drive the large-scale ...

2010-01-01

300

Temperature and current coefficients of lasing wavelength in tunable diode laser spectroscopy  

UK PubMed Central (United Kingdom)

The factors determining temperature and current coefficients of lasing wavelength are investigated and discussed under monitoring CO2-gas absorption spectra. The diffusion rate of...Full Text Available

2010-08-01

301

Spectroscopic studies of the type 2 and type 3 copper centres in the mercury derivative of laccase.  

UK PubMed Central (United Kingdom)

U.v.-visible-absorption and e.p.r. spectroscopy were used to study the type 2 and type 3 copper centres in the mercury derivative of laccase. After treatment with peroxide the mercury derivative of...Full Text Available

1989-10-15

302

Some Properties of Composite Panels Made from Wood Flour and Recycled Polyethylene  

UK PubMed Central (United Kingdom)

This study investigated the effect of board type (unmodified vs. MAPE modified) on the surface quality and thickness swelling-water absorption properties of recycled high density polyethylene (HDPE)...Full Text Available

303

Sec24C is required for docking the prechylomicron transport vesicle with the Golgi  

UK PubMed Central (United Kingdom)

The rate-limiting step in the transit of dietary fat across the intestinal absorptive cell is its exit from the endoplasmic reticulum (ER) in a specialized ER-to-Golgi transport vesicle, the prechylomicron...Full Text Available

2010-05-01

304

Ring opening reaction dynamics of a photochromic diarylethene derivative dye  

International Nuclear Information System (INIS)

Ring opening dynamics of diarylethene derivative (BTF6) in n-hexane are studied by femtosecond transient absorption and time resolved spontaneous fluorescence techniques. Cyclo-reversion time constant is obtained.

2001-11-01

305

Photo-induced transformation of close Frenkel pairs in strontium fluoride  

International Nuclear Information System (INIS)

Laser-induced change is studied of the optical absorption and luminescence due to F-H pairs generated by an electron pulse in SrF_2. It is found that laser irradiation near 2.34 eV at a delay of 26 #mu#s after an electron pulse by which F-H pairs are generated reduces the component I of the pairs that has a decay time of 59 #mu#s and optical absorption bands at 2.34 and 4.13 eV and enhances the component II that has a decay time of 7.7 ms and has optical absorption bands at 2.7 and 3.35 eV. Laser irradiation near 2.7 eV at a delay of 4 ms after the electron pulse is found to induce the reverse reaction. Studies of dichroism of the laser-induced reduction and enhancement of the optical absorption bands and the luminescence reveal that the direction of the #SIGMA#-#SIGMA# transition of the F_2"- molecular ion is converted by the transformation from I to II and vice versa. It is suggested that the ...

306

Optical properties of A-15 thin films and single crystals  

Energy Technology Data Exchange (ETDEWEB)

Optical absorptance spectra of A-15 compounds were taken using a calorimetric technique in the range 0.2 eV to 4.0 eV. Thermomodulation spectra were taken on several A-15 sputtered films.

1980-01-01

307

Optical properties of A-15 thin films and single crystals  

International Nuclear Information System (INIS)

Optical absorptance spectra of A-15 compounds were taken using a calorimetric technique in the range 0.2 eV to 4.0 eV. Thermomodulation spectra were taken on several A-15 sputtered films.

308

On-line real-time measurements of decontamination factor for a low-level waste incinerator  

Energy Technology Data Exchange (ETDEWEB)

The experiments at the incinerator for low-level wastes processing, (containing transuranium radionuclides) are described. Air decontamination factors and detector readings correction factors for efficiency and absorption are indicated.

1983-01-01

309

On-line real-time measurements of decontamination factor for a low-level waste incinerator  

International Nuclear Information System (INIS)

The experiments at the incinerator for low-level wastes processing, (containing transuranium radionuclides) are described. Air decontamination factors and detector readings correction factors for efficiency and absorption are indicated.

310

Multicomponent Breath Analysis With Infrared Absorption Using Room-Temperature Quantum Cascade Lasers  

UK PubMed Central (United Kingdom)

Breath analysis is a powerful noninvasive technique for the diagnosis and monitoring of respiratory diseases, including asthma and chronic obstructive pulmonary disease (COPD). Nitric oxide...Full Text Available

2009-12-11

311

Isolation of Assimilatory- and Dissimilatory-Type Sulfite Reductases from Desulfovibrio vulgaris  

UK PubMed Central (United Kingdom)

Bisulfite reductase (desulfoviridin) and an assimilatory sulfite reductase have been purified from extracts of Desulfovibrio vulgaris. The bisulfite reductase has absorption maxima...Full Text Available

1973-08-01

312

Interpreting the visible absorption bands of 1,4-(dihydroxy)-9,10-anthraquinone and its metal chelates.  

Science.gov (United States)

The visible absorption spectra of 1,4-(dihydroxy)-9,10-anthraquinone and of Co(II), Ni(II), Cu(II) and Zn(II) chelates have been studied in different organic solvents. This system provides a model for the anthracycline antibiotics and their metal chelates. The band structure of the spectrum has been determined using the second and fourth derivatives of the spectrum. The visible absorption band of the parent molecule can be assigned to a single electronic state with a reduced dipole moment in the excited state; structure in this band is ascribed to two overlapping vibrational progressions. In contrast, the dianion (hydroxy protons removed) shows a single electronic state with an increased dipole moment in the excited state; structure in this band can be assigned to a single vibrational progression. All of the metal chelates show spectra which are similar in appearance to that of the dianion although the identity of the metal determines the ...

1990-08-15

313

Influence of 2,3-dimercaptosuccinic acid on gastrointestinal lead absorption and whole-body lead retention  

International Nuclear Information System (INIS)

2,3-Dimercaptosuccinic acid (DMSA) is a new orally active heavy metal chelator for the treatment of childhood Pb intoxication on an outpatient basis. The influence of DMSA, as well as other chelating agents, on gastrointestinal 203Pb absorption and whole-body "2"0"3Pb retention was examined. Groups of Sprague-Dawley rats (230-260 g) were gavaged with a solution containing approximately 25 mg/kg Pb [as Pb(NO_3)2] plus 15 microCi "2"0"3Pb. Some groups were then immediately given 0.11 mmol/kg of either DMSA, CaNa2EDTA, D-penicillamine, or BAL by oral gavage, while other groups received the same drugs by ip injection. Control groups received solutions of the drug vehicles po or ip. Whole-body Pb retention and gastrointestinal Pb absorption (whole body retention + urinary Pb excretion) were significantly decreased in rats that received DMSA po. This finding implies that the use of DMSA to treat childhood lead intoxication on an outpatient basis is ...

314

Independent Emission and Absorption Abundances for Planetary Nebulae  

CERN Document Server

Emission-line abundances have been uncertain for more than a decade due to unexplained discrepancies in the relative intensities of the forbidden lines and weak permitted recombination lines in planetary nebulae (PNe) and H II regions. The observed intensities of forbidden and recombination lines originating from the same parent ion differ from their theoretical values by factors of more than an order of magnitude in some of these nebulae. In this study we observe UV resonance line absorption in the central stars of PNe produced by the nebular gas, and from the same ions that emit optical forbidden lines. We then compare the derived absorption column densities with the emission measures determined from ground-based observations of the nebular forbidden lines. We find for our sample of PNe that the collisionally excited forbidden lines yield column densities that are in basic agreement with the column densities derived for the same ions from the ...

2008-01-01

315

Hydroxylation of 3-Nitrotyrosine and Its Derivatives by Gamma Irradiation  

Science.gov (United States)

... the hydroxyl group with the benzene ring. The molar extinction coefficients for the various species at their respective absorption ... Glya Recorded by 1H-NMR Spectroscopy TABLE 2 Molar Extinction Coeff...

316

Gas purification and decomposition plants  

Energy Technology Data Exchange (ETDEWEB)

The various steps of gas treatment in the Sasol II coal liquefaction plant are discussed: CO/sub 2/ removal, separation of the hydrocarbon fractions and the recirculated hydrogen by low-temperature decomposition, production of pure hydrogen by alternating pressure absorption.

1982-11-01

317

Fully relativistic analysis of the absorption spectra of Ca_3Sc_2Ge_3O_1_2:Ni"2"+  

International Nuclear Information System (INIS)

Systematic analysis of the energy level schemes, ground state absorption (GSA) and covalency effects for the Ni"2"+ ion in Ca_3Sc_2Ge_3O_1_2 was performed. The recently developed first-principles approach to the analysis of the absorption spectra of impurity ions in crystals based on the discrete variational multi-electron method (DV-ME) [K. Ogasawara et al., Phys. Rev. B 64, 115413 (2001)] was used in the calculations. As a result, complete energy level schemes of Ni"2"+ and its absorption spectra at both possible crystallographic positions (distorted octahedral Sc"3"+ and tetrahedral Ge"4"+ positions) were calculated, assigned and compared with experimental data. Energies of the charge transfer (CT) transitions for both positions are estimated. Numerical contributions of all possible electron configurations into the calculated energy states were determined. By performing analysis of the molecular orbitals (MO) population, ...

2006-10-01

318

Frequency-dependent energy absorption in the body and tail of the rodent carcass exposed to radiofrequency radiation. Final report, 31 June-31 December 1985  

Energy Technology Data Exchange (ETDEWEB)

The proportion of energy absorbed by the tail of a rat carcass was determined. Male (288 g - 457 g) and female (195 g - 249 g) Sprague-Dawley rat carcasses were exposed to far-field, continuous-wave radiofrequency radiation (RFR). The carcasses were split into two mixed groups: one group was exposed to 700-MHz RFR; and the other, to 350-MHz RFR. Immediately after each exposure, the tail was severed, and the specific absorption rates (SAR) of the tail and body were determined by Dewar flask calorimetry. For example, a 195 g female exposed to 700 MHz yielded SARs of 1.26 and 3.64 mW/g (normalized to 1 nW/cm2 incident power density) for its body and tail, respectively; the tail contributed 6.7% to the total energy absorption. For a 205 g female exposed to 350 MHz, however, the tail contributed 19.0% to the whole-body absorption. Normalized SARs of 0.40 and 4.03 nW/g per mW/cm2 were obtained for the body and tail, respectively.

1987-04-01

319

Correlations between surface structure and catalytic activity/selectivity  

Energy Technology Data Exchange (ETDEWEB)

Work continued on the correlations of catalytic activity of metals and surface structure. Work is described in the following areas: CO oxidation on a Cu/Rh(100) Bimetallic catalysts; electronic properties of bimetallic surfaces; and reflection absorption spectroscopy of bimetallic surfaces. 5 figs. (CBS)

1990-11-01

320

Complexes of hepatitis B surface antigen and immunoglobulin M in the sera of patients with hepatitis B virus infection.  

UK PubMed Central (United Kingdom)

Hepatitis B surface antigen (HBsAg) bound to immunoglobulin M (IgM) was detected in sera of HBsAg carriers by a radioimmunoassay based on selective absorption of the immunoglobulin on a solid phase...Full Text Available

1983-09-01

321

Bioavailability of lead in rats fed human diets  

International Nuclear Information System (INIS)

The bioavailability of lead was studied in rats fed various baby foods (Babymix-turkey, Babymix-vegetables, Frutolino-fruit, Frutamix-bananas, Babyron-S-26, Truefood), cow's milk, bread, liver and standard rat diet. Lead absorption was determined by measuring the whole body retention of "2"0"3Pb 6 days after a single oral application. Highest absorption values ranging from 17 to 20% were obtained in animals fed cow's milk and fruit foods. Rats on other human diets absorbed between 3 and 8% of the radioactive lead dose. Only in animals on rat diet lead absorption was below 1%. It is concluded that rats fed human diets show absorption values similar to those in humans. This might indicate that the bioavailability of lead is primarily dependent on dietary habits. This experimental model, if confirmed by further work, might be useful for obtaining preliminary data on the bioavailability of metals from ...

322

Anaerobic reactions of Rhus vernicifera laccase and its type-2 copper-depleted derivatives with hexacyanoferrate(II).  

UK PubMed Central (United Kingdom)

Anaerobic reactions of Rhus vernicifera laccase and its type-2 copper-depleted derivatives with hexacyanoferrate(II) were investigated by absorption and e.s.r. spectroscopy. When native laccase was...Full Text Available

1992-06-15

323

Acute Drug-Induced Hepatitis Caused by Albendazole  

UK PubMed Central (United Kingdom)

Albendazole binds to parasite's tubulin inhibiting its glucose absorption. Its common adverse effects are nausea, vomiting, constipation, thirst, dizziness, headache, hair loss and pruritus. Although...Full Text Available

2008-10-01

324

Absorption of the atmospheric CO{sub 2} by oceanic biota near the air-sea interface  

Energy Technology Data Exchange (ETDEWEB)

The oceanic phytoplancton productivity may essentially influence the total rate of the atmospheric CO{sub 2} absorption by the ocean - that is, a considerable amount of CO{sub 2} will be taken-up in the 50 micrometers thick layer near the air-sea interface. Even if phytoplancton production constitutes only 5% of the total oceanic biota production, this will increase the rate of CO{sub 2} absorption more than twice compared with the present estimates. The reason is that metabolic activity of phytoplancton leads to the emergence in a thin scin (50 micrometers, the average size of phytoplancton cells) layer near the water surface of an additional minimum in the CO{sub 2} partial pressure profile and of an additional maximum of {Delta} {sup 13}C in the same area. These two extremums cannot be detected if the corresponding characteristics are averaged over any microscopic area in the well mixing layer that is more than 1 meter deep, which is usually ...

1997-12-31

325

Absorption of tachyons in extended relativity an answer to Basano  

International Nuclear Information System (INIS)

It is answered to a previous letter by Basano, and shown that the difficulties met by that author within ''Extended relativity'' do not exist, but are due to the erroneous assumption that a certain condition for tachyons to be absorbed by a macro-object is sufficient (whilst it is only a necessary one).

326

Absorption of CO{sub 2}, H{sub 2}, S, and NO using dry FGD wastes  

Energy Technology Data Exchange (ETDEWEB)

Limestone-based sorbents are used extensively in utility boilers and tail-gas desulfurization units to remove sulfur oxides formed during the combustion of fossil fuels. Such units generate {approximately}20 million tons of flue-gas desulfurization (FGD) wastes in the U.S. annually, the bulk of which ({approximately}95%) are discarded in landfills or holding ponds. However, a significant portion of the Ca in these materials is not sulfated (remains as CaO or Ca(OH){sub 2}), particularly in units that generate dry wastes. When hydrated, such wastes exhibit a strong affinity to absorb acid gases at ambient temperature. This study represents a continuation of previously reported CO{sub 2}-absorption studies and includes more recent work on the absorption of H{sub 2}S and NO. Ten FGD-waste samples along with a control fly ash were examined. Absorption capacities, the role of available calcium and particle size, and mineralogic ...

1996-10-01

327

Study of vibrational relaxation in the active medium of a CO/sub 2/-laser by the phase-absorption method  

Energy Technology Data Exchange (ETDEWEB)

The authors attemps to confirm a modification of the phase-absprotion method applicable to the study of the decay rate of energy stored in the upper level in the active medium of a CO/sub 2/-laser. The essence of the method is described. Relationships are determined which allow one to obtain the unknown parameters of the experimentally measured phase shift. The work exeprimentally shows the possibility of studying vibratioanl relaxation in the active medium of a CO/sub 2/-laser by the phase-absorption method using both ordinary and isotope-substitued molecules.

1986-09-01

328

Numerical investigation of carbon dioxide absorption in a falling-film micro-contactor  

Energy Technology Data Exchange (ETDEWEB)

A rigorous mathematical model is developed to describe chemical absorption of carbon dioxide in a falling-film micro-contactor. Contrary to previous models described in literature, hydrodynamics in both phases is accurately captured by the Navier-Stokes equations. By this means, backmixing effects can be accounted for. Furthermore, the interface position is determined directly using the level-set method. The developed model is validated with experimental data obtained from literature and a good agreement is established. With the validated model, detailed studies are performed to investigate the impact of process parameters.

2010-02-01

329

Nuclear borehole logging using lithium detector assemblies  

International Nuclear Information System (INIS)

A method and apparatus for nuclear borehole logging, and in particular, neutron porosity logging, uses a neutron source, and a pair of spaced lithium detectors, preferably Li"6I crystal or Li"6 doped glass, to detect neutrons emitted from a borehole formation being logged. The spectrum developed by the lithium detectors is processed to remove the gamma ray background radiation and the hydrogen absorption peak, thus allowing a more accurate neutron count. A Gaussian curve is fitted to the neutron peak of the spectrum, the curve eliminating the hydrogen absorption peak. The area under this Gaussian curve represents the neutron count. (author).

1991-11-01

330

Modeling and Experimental Study of Carbon Dioxide Absorption in a Membrane Contactor  

Energy Technology Data Exchange (ETDEWEB)

This dissertation deals with membrane gas absorption in the application of CO{sub 2} removal by aqueous alkanolamines, using microporous PTFE hollow fiber membranes. A new lab-scale apparatus was constructed and an extensive experimental study executed to determine the performance of the membrane gas absorber, with aqueous solutions of monoethanolamine (MEA) and methyldiethanolamine (MDEA) as absorbents. The important operation parameters CO{sub 2} partial pressure, gas velocity, liquid velocity, temperature and liquid CO{sub 2} loading were systematically varied within the range typically experienced in a process for exhaust gas CO{sub 2}-removal

2003-03-15

331

Mathematical model of absorption of carbon dioxide by rescur breathing apparatus scrubber  

Energy Technology Data Exchange (ETDEWEB)

The author presents a mathematical model for analysis of the impact of scrubber bed length, porosity, and gas flow rate on the absorption of CO{sub 2} in a breathing apparatus. The model accounts for the decrease in available absorbent through chemical conversion. The predicted efflux of CO{sub 2} from a canister containing LiOH compared favorably with measured values reported elsewhere. It was determined from a computational study that the time for breakthrough of CO{sub 2} at a prescribed level is nearly directly proportional to bed length and inversely proportional to gas flow and porosity.

1987-01-01

332

Manifestation of isotope effects in absorption spectra of "1"4"4Sm"3"+ and "1"5"4Sm"3"+ in solutions  

International Nuclear Information System (INIS)

Photoluminescence spectra for solutions containing Sm"3"+ isotope ions in heavy and normal water were studied in the wave length #lambda# = 500-700 nm and for absorption spectra and photoluminescence excitation spectra within the range of #lambda# = 260-600 nm. Differences in molar extinction coefficients for "1"4"4Sm"3"+ and "1"5"4Sm"3"+ were established both in the solutions with D_2O and by transition from the solutions with D_2O to the solutions with H_2O. New possible causes of the identified effects are discussed

1998-01-01

333

Interpretation of EXAFS data from laser shock compressed plasmas  

Energy Technology Data Exchange (ETDEWEB)

Measurements on laser shock compressed aluminium using the EXAFS (Extended X-ray Absorption Fine Structure) technique on the Al K-edge are described. Two methods of analysis of this data were used for the determination of density: the standard EXAFS technique using Fourier transforms and curve fitting, and a method based on a bandstructure calculation of the absorption spectra as a function of compression. These two techniques give results which are in fairly good agreement with each other and also with a hydrodynamic simulation of the experiment. The ion correlation parameter is estimated and shows that two-sided laser irradiation of aluminium foils produces a dense plasma which is strongly coupled. (author).

1989-01-01

334

Estimation of armature condition in concrete with gamma-absorption method  

International Nuclear Information System (INIS)

Bases of the algorithm for assessing the reinforcement status in reinforced concrete products by gamma-absorption method are presented. Analytical equations are obtained for estimation of error of the parameter characterizing the degree of reinforcement destruction. It is recommended to use high-energy Bremsstrahlung sources-betatrons of 4-10 MeV maximum energy for testing products of 500-600 mm thick. Linear radiation attenuation factor (LAF) of concrete in estimated equation is replaced by effective LAF of concrete, and LAF of reinforcement and corrosion materials - by differential LAF. Corresponding LAF of nonevident form in the algorithm is assessed by the results of processing of direct-shadow radiographs of defectometers

335

Computer processing of Moessbauer spectrum data  

International Nuclear Information System (INIS)

Computer processing was adopted to pick up significant signals from the undefined Moessbauer spectra. A program, by which smoothing and curve fitting was made possible, was devised and applied to the analysis of the Moessbauer spectra of "5"7Fe enriched iron and other specimens. Although this processing sometimes distorted the absorption peaks, it was quite effective for elimination of noise and finding of exact positions of absorption peaks. Availability of the processing was demonstrated by several examples obtained for "5"7Fe enriched iron, natural iron, calcined ferric oxyhydroxides, red mud residue and its calcined product. (auth.).

336

Choice of energies in gamma-absorption method for layers thickness measuring of two-layers articles  

International Nuclear Information System (INIS)

Empirical formulae are proposed for the description of relation between optimum energies minimizing the mean-weighted error of gamma absorption measurement of the thickness of layers in two-layer products with the thickness of every layer from 30 up to 150 mm by carbon. Error of informational parameter approximation with the application of tables does not exceed 10% in case of non-accurate assessment of layers thickness not exceeding 2.5%. Generalized equation is derived which binds main parameters of the task and permits to choose optimum energies with the accuracy sufficient for practical purposes

337

Choice of distance from radiation source to tested object for gamma-absorption density measurer in divergent pencil of ray  

International Nuclear Information System (INIS)

Formulae are derived for estimation of the effect of gamma beam divergence on the value of systematic and statistical components of the errors of density measurement in production of structural materials and products also in the process of exploitation of building structures and constructions. Engineering technique for choice of the distance between radiation source and object under test is developed for absorption radioisotope densimeter operating by the scheme of geometry of divergent beam with amplitude compensation of backscattered radiation effect. The assessment of radioisotope densimeter efficiency providing the error of density measurement prescribed at design stage

338

Chemical absorption and desorption of carbon dioxide from hot carbonate solutions. [Rate data from 0 to 110/sup 0/C  

Energy Technology Data Exchange (ETDEWEB)

Absorption and desorption rate data for the system CO/sub 2/-hot carbonate solutions are presented. The data are interpreted on the basis of a film-theory model developed following the procedure recently presented by Astarita and Savage. The agreement is very satisfactory. Values of the kinetic constant of the rate-determining step, previously known only up to a temperature of 40/sup 0/C, have been obtained up to 110/sup 0/C.

1980-01-01

339

CO2 CAPTURE BY ABSORPTION WITH POTASSIUM CARBONATE  

Energy Technology Data Exchange (ETDEWEB)

The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. Progress has been made in this reporting period on three subtasks. A simple thermodynamic model has been developed to represent the CO{sub 2} vapor pressure and speciation of the new solvent. A rate model has been formulated to predict the CO{sub 2} flux with these solutions under absorber conditions. A process and instrumentation diagram and process flow diagram have been prepared for modifications of the existing pilot plant system.

2002-10-01

340

Accurate determination of detection efficiency and self-absorption factors in measuring radon daughter  

International Nuclear Information System (INIS)

The detection efficiency of #alpha# particles of "2"1"4Po 7.69 MeV and "2"1"8Po 6.00 MeV in measuring radon daughters were determined through the data which were measured with long-lived #alpha# standard source and radon daughter standard source and with curve-fitting method of general formulation. The indeterminacy was #<=#2.5% and #<=#2.7% respectively. Their ranges in filter membrane were also determined, and the effect of the indeterminacy on the self-absorption factors was #<=#1.3%.

341

Study on the application of a geothermal heat pump; Etude sur l`application d`une pompe a chaleur geothermique  

Energy Technology Data Exchange (ETDEWEB)

The heating system of the `Centre integre de mecanique industrielle de la Chaudiere`, in Saint-Georges, Quebec, is based on a solar wall and a geothermal heat pump with a glycol/water mixture circulating in 44 wells that are 100 m deep. With installation costs below $25 per sq.m, more than 85 per cent of the heating needs of the 9500 sq.m centre were supplied by geothermal power. The geothermal heat pump is composed of a well field and two 211-kW cooling units, each equipped with four coiled compressors. In winter, heat is pumped from the earth and in summer, a heat exchanger with control valves allows to heat to be dumped back into the earth. The monitoring and simulation of the system proved its efficiency, considering the climatic conditions in Quebec. The annual consumption of geothermal heating is 0.146 GJ per sq.m, ...

1996-12-01

342

Heat pumps in urban space heating systems: Energy and environmental aspects  

International Nuclear Information System (INIS)

A statistical survey is conducted of air pollution in the city of Rome (Italy) due to conventional building space heating systems burning fossil fuels. The survey identifies the annual consumption of the different fuels and the relative amounts of the various pollutants released into the atmosphere by the heating plants, e.g., sulfur and nitrogen oxides, carbon monoxide, etc. Comparisons are then made between the ratios of urban heating plant air pollutants produced per tonne of fuel employed and those for ENEL (Italian National Electricity Board) coal, oil and natural gas fired power plants, in order to demonstrate the better environmental performances of the utility operated energy plants. The building space heating system energy consumption and pollution data are then used in a cost benefit analysis favouring the retrofitting of conventional heating systems with ...

1991-01-01

343

Augmentation of heat transfer in heat conductive medium by electro-hydrodynamic effect  

Energy Technology Data Exchange (ETDEWEB)

A method of augmenting heat transfer in the interior of a fluid or from the interface of a solid in contact to a fluid by utilizing electro hydrodynamic (EHD) phenomena has the following advantages: the heat transfer can be effected by using a relatively small, light-weight high voltage source and some simple structural members; no vibration and noise are generated; the method has a control function to control heat transfer by adjustment of field and voltage; and this method is effective in cost-saving. It is mass transfer by the electric force caused by interaction between true charges or polarized charges in a fluid and external electric filed that plays an important role in most of such heat transfer augmentation methods by EHD. Examples of heat transfer augmentation by EHD phenomena include electricaly induced convection, contribution of EHD effect to heat ...

1988-04-20

344

Isotope aided studies of the bioavailability of iron and zinc from human diets consumed in Venezuela  

International Nuclear Information System (INIS)

Previous studies on Venezuelan diets provided information on food consumed in each diet and their nutritional contents. It also showed the comparison of the iron absorption from these diets when given in the morning after over-night fast and when given at the customary time of the day. It was observed that the iron absorption from the lunch given at noon was slightly higher (although not significant) in Zulia and Sucre diets. There were no significant differences between the Zulia lunch given in the morning after over-night fast at noon. Similar results were observed in the Sucre diet lunch repeated twice. From these results we can state that iron absorption from meals is not affected by the time it is administered with the condition that the subjects tested have had a previous fast of three hours before the meal is administered. The significant difference in iron absorption in the first study could be ...

1992-11-16

345

Ground and excited state absorption of Ni{sup 2+} ions in MgAl{sub 2}O{sub 4}: Crystal field analysis  

Energy Technology Data Exchange (ETDEWEB)

The exchange charge model (ECM) of crystal field is utilized to provide the theoretical explanation of the ground state absorption and the excited state absorption observed for the octahedrally coordinated Ni{sup 2+} ions in the spinel MgAl{sub 2}O{sub 4}. The ECM enables modeling of the crystal field parameters (CFPs) for the impurity ions based on the crystal structure data of the host lattice. To ensure the reliability of the CFPs, the convergence of the CFP values with the increasing number of the coordination spheres taken into account in the ECM calculations is considered. The trigonal CFPs B{sub 2}{sup 0},B{sub 4}{sup 0}andB{sub 4}{sup -3} determined by the ECM, together with the appropriate Racah parameters B and C, serve as input to two crystal field analysis computer packages, which compute the energy level schemes within the whole 3d{sup 8} configuration. The cubic approximation utilizing only one CFP Dq is also discussed. Basic ...

2007-04-25

346

Design of spacecraft thermal control materials on polyimide film; Polyimide film ni yoru uchuyo netsuseigyo zairyo no kaihatsu  

Energy Technology Data Exchange (ETDEWEB)

Two types of thermal control materials based on polyimide film UPILEX-R are designed. One of thermal control material R/Al is coated with Al on the back surface. The other of thermal control material TCC/R/Al is coated with transparent conductive coating on the font surface and is coated with Al on the balk surface. The solar absorptance is measured spectroscopically with an integrating sphere in the wavelength region of 0.26 - 2.50 {mu}m and the total hemispherical emittance is measured calorimetrically in the temperature range of -100-+100{degree}C for the present thermal control materials. To evaluate the space degradation of optical properties (refractive index, extinction coefficient, absorption coefficient) on UPILEX-R film and solar absorptance on thermal control materials, space environment simulation tests are performed on the ground with independent radiation and combined radiation by UV, electrons, and protons. ...

1996-01-20

347

A pilot-scale jet bubbling reactor for wet flue gas desulfurization with pyrolusite.  

Science.gov (United States)

MnO2 in pyrolusite can react with SO2 in flue gas and obtain by-product MnSO4 x H2O. A pilot scale jet bubbling reactor was applied in this work. Different factors affecting both SO2 absorption efficiency and Mn2+ extraction rate have been investigated, these factors include temperature of inlet gas flue, ration of liquid/solid mass flow rate (L/S), pyrolusite grade, and SO2 concentration in the inlet flue gas. In the meantime, the procedure of purification of absorption liquid was also discussed. Experiment results indicated that the increase of temperature from 30 to 70 K caused the increase of SO2 absorption efficiency from 81.4% to 91.2%. And when SO2 concentration in the inlet flue gas increased from 500 to 3000 ppm, SO2 absorption efficiency and Mn2+ extraction rate decreased from 98.1% to 82.2% and from 82.8% to 61.7%, respectively. The content of MnO2 in pyrolusite had a neglectable effect on ...

2005-01-01

348

Development of fire simulation models for radiative heat transfer and probabilistic risk assessment  

Energy Technology Data Exchange (ETDEWEB)

An essential part of fire risk assessment is the analysis of fire hazards and fire propagation. In this work, models and tools for two different aspects of numerical fire simulation have been developed. The primary objectives have been firstly to investigate the possibility of exploiting state-of-the-art fire models within probabilistic fire risk assessments and secondly to develop a computationally efficient solver of thermal radiation for the Fire Dynamics Simulator (FDS) code. In the first part of the work, an engineering tool for probabilistic fire risk assessment has been developed. The tool can be used to perform Monte Carlo simulations of fires and is called the Probabilistic Fire Simulator (PFS). In Monte Carlo simulation, the simulations are repeated multiple times, covering the whole range of variability of the input parameters and thus resulting in a distribution of results covering what can be expected in reality. In practical applications, advanced simulation techniques ...

2008-07-01

349

The two-dimensional Stefan problem with slightly varying heat flux  

Science.gov (United States)

The authors solve the two-dimensional stefan problem of solidification in a half-space, where the heat flux at the wall is a slightly varying function of positioning along the wall, by means of a large Stefan number approximation (which turns out to be equivalent to a small time solution), and then by means of the Heat Balance Integral Method, which is valid for all time, and which agrees with the large Stefan number solution for small times. A representative solution is given for a particular form of the heat flux perturbation.

1995-09-01

350

The adiabatic engine:Global developments  

Energy Technology Data Exchange (ETDEWEB)

This book presents papers on internal combustion engines. Topics considered include the influence of partial suppression of heat rejection on performance and emissions, duothermic combustion, turbochargers made of sintered silicon nitrides, heat flux, low heat rejection engines, exhaust energy recovery, combustion chamber insulation, computerized simulation, heat transfer, friction, hoop stress effects, and bonding ceramics and metals.

1986-01-01

359

Neutron star evolution with internal heating  

Science.gov (United States)

The thermal evolution predicted by current models of the superfluid-crust interaction is noted to

1989-01-01

363

Long- but not short-term heat acclimation produces an apoptosis-resistant cardiac phenotype: a lesson from heat stress and ischemic/reperfusion insults  

UK PubMed Central (United Kingdom)

Long-term heat acclimation (AC, 30d/34°C) is a phenotypic adaptation leading to increased thermotolerance during heat stress (HS, 2 h 41°C). AC also renders protection against...Full Text Available

2010-09-01

365

High temperature heat transfer augmentation  

International Nuclear Information System (INIS)

The heat transfer augmentation is reviewed in view of high temperature heat exchangers illuminating the contribution of radiative heat transfer. A number of means and/or devices are presented as well as the sophisticated concept which will be promoted to the extended applications in matured industries such as iron and steel, oir refinery, petro-chemical. It should be emphasized that the more creative and innovatory technology has to be promoted in order to stimulate and refresh the foregoing industries, recognizing the increasing importance of the energy resources.

1985-08-01

366

Heat transfer augmentation by interrupted surfaces - Experimental considerations  

International Nuclear Information System (INIS)

An experimental study was undertaken to determine for the turbulent regime the heat transfer and fluid flow characteristics of a heat exchange array of unperforated, and perforated brass plates with 33% of the plate area open. In both cases, the plates were aligned parallel to the flow direction. For the flow conditions examined, the results showed enhancement of heat transfer and friction factor for the perforated array.

1987-08-01

367

Heat stress upregulates chaperone heat shock protein 70 and antioxidant manganese superoxide dismutase through reactive oxygen species (ROS), p38MAPK, and Akt  

UK PubMed Central (United Kingdom)

Chinese hamster lung fibroblasts V79 cells were treated with heat stress for 4 weeks with short duration (15 min) heat shock every alternate day in culture. It was observed that Hsp...Full Text Available

2009-11-01

368

Heat recovery in foundries  

Energy Technology Data Exchange (ETDEWEB)

A great deal of energy is necessary to manufacture castings, the greater part of which is wasted. Some general instructions are given on how to keep this part as low as possible. This is discussed particularly using the example of a heat recovery plant for foundries, especially in the melting and cooling of castings with the use of cupola furnace stack gas to produce hot gas. Further variants for recovering heat from the individual stages of a foundry process are listed. There are data on using this heat in operation.

1982-01-01

369

Heat capacities and densities of electrolyte mixtures in aqueous solution - application to the determination of apparent molar heat capacities and volumes for potassium triiodide and dioxoneptunium(V) perchlorate  

Energy Technology Data Exchange (ETDEWEB)

Apparent molar heat capacities for KI[sub 3](aq) were determined from flow-microcalorimetric measurements of KI(aq) solutions containing dissolved iodine. From these, the conventional partial molar heat capacity C[sub p,2][sup [infinity

1993-05-01

371

Geothermal heat pumps - gaining ground in the UK and worldwide  

Energy Technology Data Exchange (ETDEWEB)

This 2001 edition of the guide to UK renewable energy companies examines the geothermal heat pump sector, and discusses the technology involved, installations of geothermal heat pumps, the activity in the UK market with increased interest in UK geothermal heat pump products from abroad, and developments in the building sector. The UK government's increased support for the industry including its sponsorship of the Affordable Warmth programme, and the future potential of ground source systems are discussed.

2001-07-01

372

Geothermal heat pumps - gaining ground in the UK and worldwide  

International Nuclear Information System (INIS)

This 2001 edition of the guide to UK renewable energy companies examines the geothermal heat pump sector, and discusses the technology involved, installations of geothermal heat pumps, the activity in the UK market with increased interest in UK geothermal heat pump products from abroad, and developments in the building sector. The UK government's increased support for the industry including its sponsorship of the Affordable Warmth programme, and the future potential of ground source systems are discussed.

373

Geothermal heat pump  

Energy Technology Data Exchange (ETDEWEB)

Ground water ranging in temperature from only 38/sup 0/ to 140/sup 0/F can supply a considerable amount of heat energy when couple with a geothermal or ground-water heat pump. The heat pump's method of operation is examined as well as its performance characteristics. (MHR)

1982-12-01

375

Experimental investigation for fluid flow and heat transfer in a rotating tube with twisted-tape inserts  

Energy Technology Data Exchange (ETDEWEB)

Experimental investigation was carried out for friction factor and heat transfer coefficient in the case of a rotating tube with a twisted-tape insert for heat transfer augmentation. The data obtained were compared with existing data for a stationary tube with a twisted-tape insert. It has been observed that the enhancement in heat transfer offsets the rise in friction factor due to rotation, with respect to a plain tube under stationary conditions. A correlation has been proposed for the data obtained.

1995-04-01

385

Time-dependent fluid flow and heat transfer around a circular heated cylinder embedded in a horizontal packed bed of spheres  

Science.gov (United States)

The present study numerically investigates the enhancement of forced convective heat transfer from a single circular cylinder embedded in a packed bed of spherical particles confined by two impermeable parallel plates. The heat transfer results from the heated cylinder, with and without the presence of a porous medium, are compared. The results show that the presence of the porous particles enhances the heat transfer from the cylinder; however, the significant heat transfer augmentation is produced at high Re due to the effect of thermal dispersion. In addition, the effect of Re on Nut is much greater than that of kr and Bi in the porous channel. It is also found that the %?p is much higher than %HTE producing from packing the empty channel.

2010-05-01

386

The thermal response of an infinite line of open loop wells for ground coupled heat pump systems  

British Library Electronic Table of Contents (United Kingdom)

Ground thermal energy storage is a means of storing thermal energy underground during the summer and utilizing it during the winter. The main use of such a technology is in the heating, ventilating and air conditioning sector where the ground provides a stable temperature reservoir for a heat pump system. Heat pumps are mechanical systems that provide heating to a space in the winter, and cooling in the summer. They are increasingly popular because the same system provides both heating modes, depending on the direction of the cycle upon which they operate. The stable temperature reservoir allows the heat pump system to run at a higher efficiency. Thermal energy is transmitted to and from the ground by circulation of water through standing column geothermal wells. In commercial applications...

2011-01-01

387

The temporal evolution of coronal loops observed by GOES-SXI  

CERN Document Server

We study the temporal evolution of coronal loops using data from the Solar X-ray Imager (SXI) on board of GOES-12. This instrument allows us to follow in detail the full lifetime of coronal loops. The observed light curves suggest three somewhat distinct evolutionary phases: rise, main, and decay. The durations and characteristic timescales of these phases are much longer than a cooling time and indicate that the loop-averaged heating rate increases slowly, reaches a maintenance level, and then decreases slowly. This suggests that a single heating mechanism operates for the entire lifetime of the loop. For monolithic loops, the loop-averaged heating rate is the intrinsic energy release rate of the heating mechanism. For loops that are bundles of impulsively heated strands, it is an indication of the frequency of occurrence of individual heating events, or ...

2006-01-01

388

The feasibility of using a septic tank as a heat source for geothermal heat pumps  

Energy Technology Data Exchange (ETDEWEB)

A geothermal heat pump (GHP) system with three ground coils was installed in a residence in northern Idaho with a portion of the ground heat exchanger wrapped around the residential septic tank. The septic coil provided a significant portion of the heating for the residence over the heating season. There was no evidence of the septic tank freezing up or failing to properly function. Utilizing a septic tank as a heat source for GHP systems is feasible design option if the septic tank is used on a full-time basis. However, the tank should be surrounded on all sides by a large amount of soil and/or insulated from the ground surface to ensure that ground temperatures near the tank remain warm during the winter.

1999-11-01

389

Quantum Thermodynamic Cycles and quantum heat engines  

CERN Document Server

In order to describe quantum heat engines, here we systematically study isothermal and isochoric processes for quantum thermodynamic cycles. Based on these results the quantum versions of both the Carnot heat engine and the Otto heat engine are defined without ambiguities. We also study the properties of quantum Carnot and Otto heat engines in comparison with their classical counterparts. Relations and mappings between these two quantum heat engines are also investigated by considering their respective quantum thermodynamic processes. In addition, we discuss the role of Maxwell's demon in quantum thermodynamic cycles. We find that there is no violation of the second law, even in the existence of such a demon, when the demon is included correctly as part of the working substance of the heat engine.

2006-01-01

390

Influence of turbulence parameters, Reynolds number, and body shape on stagnation-region heat transfer  

Energy Technology Data Exchange (ETDEWEB)

This experiment investigated the effects of free-stream turbulence intensity, length scale, Reynolds number, and leading-edge velocity gradient on stagnation-region heat transfer. Heat transfer was measured in the stagnation region of four models with elliptical leading edges downstream of five turbulence-generating grids. Stagnation-region heat transfer augmentation increased with decreasing length scale but an optimum scale was not found. A correlation was developed that fit heat transfer data for isotropic turbulence to within {+-}4 percent but did not predict data for anisotropic turbulence. Stagnation heat transfer augmentation caused by turbulence was unaffected by the velocity gradient. The data of other researchers compared well with the correlation. A method of predicting heat transfer downstream of the stagnation point was developed. 28 refs., 12 ...

1995-08-01

391

Influence of turbulence parameters, Reynolds number, and body shape on stagnation-region heat transfer  

International Nuclear Information System (INIS)

This experiment investigated the effects of free-stream turbulence intensity, length scale, Reynolds number, and leading-edge velocity gradient on stagnation-region heat transfer. Heat transfer was measured in the stagnation region of four models with elliptical leading edges downstream of five turbulence-generating grids. Stagnation-region heat transfer augmentation increased with decreasing length scale but an optimum scale was not found. A correlation was developed that fit heat transfer data for isotropic turbulence to within #+-#4 percent but did not predict data for anisotropic turbulence. Stagnation heat transfer augmentation caused by turbulence was unaffected by the velocity gradient. The data of other researchers compared well with the correlation. A method of predicting heat transfer downstream of the stagnation point was developed. 28 refs., 12 ...

1995-01-01

392

Experimental investigation of mixed convection heat transfer from longitudinal fins in a horizontal rectangular channel  

British Library Electronic Table of Contents (United Kingdom)

Mixed convection heat transfer from longitudinal fins inside a horizontal channel has been investigated for a wide range of modified Rayleigh numbers and different fin heights and spacings. An experimental parametric study was made to investigate effects of fin spacing, fin height and magnitude of heat flux on mixed convection heat transfer from rectangular fin arrays heated from below in a horizontal channel. The optimum fin spacing to obtain maximum heat transfer has also been investigated. During the experiments constant heat flux boundary condition was realized and air was used as the working fluid. The velocity of fluid entering channel was kept nearly constant (0.15win0.16m/s) using a flow rate control valve so that Reynolds number was always about Re=1500. Experiments were conducted...

2010-01-01

393

Development of a solar thermal storage system suitable for the farmhouse heating in northeast China  

Energy Technology Data Exchange (ETDEWEB)

This study reported on the performance of a passive solar radiant floor heating system designed for standard energy-saving farmhouses in northeast China. Weather data in the region was analyzed in terms of solar radiation, temperature, humidity and light levels. The heating characteristics of the building materials such as windows, doors, walls and roofs were also analyzed along with the indoor thermal environment of the farmhouse. The heating load was then calculated along with the size of the thermal storage element and the area of the collector element. The passive solar radiant floor heating system was designed for heating during the winter and cooling in summer. According to the results, the heating characteristics of the system have the potential to improve farming villages environment and the use of renewable energy.

2010-07-01

394

Development and Demonstration of a High Efficiency, Rapid Heating, Low NOx Alternative to Conventional Heating of Round Steel Shapes, Steel Substrate (Strip) and Coil Box Transfer Bars  

Energy Technology Data Exchange (ETDEWEB)

Direct Flame Impingement involves the use of an array of very high-velocity flame jets impinging on a work piece to rapidly heat the work piece. The predominant mode of heat transfer is convection. Because of the locally high rate of heat transfer at the surface of the work piece, the refractory walls and exhaust gases of a DFI furnace are significantly cooler than in conventional radiant heating furnaces, resulting in high thermal efficiency and low NOx emissions. A DFI furnace is composed of a successive arrangement of heating modules through or by which the work piece is conveyed, and can be configured for square, round, flat, and curved metal shapes (e.g., billets, tubes, flat bars, and coiled bars) in single- or multi-stranded applications.

2010-01-25

395

Design and Operation of a Novel Capillary Pumped Two-Loop System for Cooling of Electronic Devices  

British Library Electronic Table of Contents (United Kingdom)

Heat pipes, loop heat pipes (LHP), and capillary pumped loops (CPL) have already proven their potential to remove high heat fluxes from a small electronic device and transport the heat to a heat sink that is large enough to transfer it into the ambient air. We introduce a novel two-loop system similar in design to CPLs but with an additional buoyancy-driven fluid loop. Non-degassed methanol is used as a working fluid. Key benefits compared to LHPs and CPLs are easy filling procedure, easy startup, and the tolerance toward noncondensable gases in the fluid. The amount of fluid in the system can be varied over a broad range without affecting the heat transfer performance. Three different inverted-meniscus-type evaporators have been employed in this study. A maximum evaporator heat transfer r...

2012-01-01

396

Basic study on heat transfer characteristics of liquid Na in a decay-heat removal system of LMFBR  

Energy Technology Data Exchange (ETDEWEB)

A numerical analysis is performed to clarify the heat transfer characteristics of combined convection around the tubes which form a single row perpendicularly arranged to a forced flow in the direction of gravity. A boundary-fitted coordinate transformation technique is adopted to solve the governing equations numerically. It is found in the case of liquid sodium that gravity-induced flow gives no substantial effect to heat transfer augmentation in a low Reynolds number region while it can be sufficiently expected in the ordinary fluids in the same Reynolds number region. This means that such heat transfer augmentation as expected in ordinary fluids can not be realized when crossflow-type heat exchangers installed for decay-heat removal operates in a low Reynolds number region.

1988-02-01

397

A study of binary mixture boiling: boiling site density and subcooled heat transfer  

Energy Technology Data Exchange (ETDEWEB)

(Boiling site densities and heat-transfer coefficients have been measured for ethanol-water and ethanol-benzene mixtures at 1.01 bar for a heated vertical brass disk. A strong effect of composition on the boiling site density was observed, which was attributed to the nature of the activation of the boiling surface and mass diffusion effects. The boiling heat-transfer coefficient was found to decrease with increasin subcooling, but for the mixtures at a given level of subcooling the decrease was less than that for the single components and azeotropic mixtures.) The heat-transfer coefficient at a given heat flux was seen to be quite insensitive to the very large increase in boiling site density in comparing the pure water and the ethanol-water azeotrope results, leading one to question pool boiling models that predict heat-transfer rates on the basis of boiling ...

1985-05-01

398

A parametric study on the exergoeconomic assessment of a vertical ground-coupled (geothermal) heat pump system  

Energy Technology Data Exchange (ETDEWEB)

An exergoeconomic model of a vertical ground-source heat pump residential heating system presented in this study uses exergy and cost energy mass (EXCEM) methods. The data obtained from a ground-source heat pump (GSHP) residential heating system installed at the Solar Energy Institute, Ege University, Turkey, are utilized for calculations at different reference temperature values in the range 0-25{sup o}C. The performance of the geothermal heat pump residential heating system is evaluated to indicate how exergoeconomic parameter values change with system. We also undertake a parametric study to investigate how varying reference temperatures will affect the exergoeconomic analysis of the GSHP system. A correlation between the ratio of thermodynamic loss rate to capital cost and reference state temperature is developed. (author)

2007-03-15

399

A metal matrix for heat transfer enhancement during phase-change processes  

Energy Technology Data Exchange (ETDEWEB)

A metal matrix is inserted into a phase-change material to enhance the heat transfer during phase-change processes. The metal matrix tends to act like a heat transfer fin from the heated or cooled surface and to increase the effective thermal conductivity of the phase-change fluid. The scope of the study involves numerically modeling the heat transfer to and from constant-temperature cylindrical tubes surrounded by water during the freezing and melting processes. Comparisons of heat transfer with and without the metal matrix are made, with different porosities and densities of the metal matrix being examined. The results of this study are discussed in terms of the effectiveness of the metal matrix as a heat transfer enhancement device.

1994-12-31

400

A basic study on heat transfer characteristics of liquid Na in a decay-heat removal system of LMFBR  

International Nuclear Information System (INIS)

A numerical analysis is performed to clarify the heat transfer characteristics of combined convection around the tubes which form a single row perpendicularly arranged to a forced flow in the direction of gravity. A boundary-fitted coordinate transformation technique is adopted to solve the governing equations numerically. It is found in the case of liquid sodium that gravity-induced flow gives no substantial effect to heat transfer augmentation in a low Reynolds number region while it can be sufficiently expected in the ordinary fluids in the same Reynolds number region. This means that such heat transfer augmentation as expected in ordinary fluids can not be realized when crossflow-type heat exchangers installed for decay-heat removal operates in a low Reynolds number region. (author).

1988-01-01

401

Study of heat reinjection mechanism of a direct-injection diesel engine. 2nd Report. Effects of combustion control item on heat flux; Chokufun diesel kikan no nensho shitsunai netsu sonshitsu no mechanism ni kansuru kenkyu. 2. Nenshokei parameter no netsu nagare eno eikyo  

Energy Technology Data Exchange (ETDEWEB)

Experimental investigations are being conducted on a single-cylinder direct-injection diesel engine to examine the effects of combustion chamber specifications and swirl ratios on the heat release and transient heat transfer characteristics. Heat rejection was examined on the basis of heat release calculations using cylinder pressure time histories. Transient surface temperature data obtained from stationary locations in the piston and cylinder head were used as the basis for determining the transient heat flux rates. The results showed good agreement with the heat rejection calculated from cylinder pressure data and that transient heat flux in a piston cavity was reduced with the larger cavity diameter and a higher swirl ratio. On the other hand, a transient heat flux in a piston head was not changed by the cavity ...

1997-09-25

402

Status of non-electric nuclear heat applications: Technology and safety  

International Nuclear Information System (INIS)

Nuclear energy plays an important role in electricity generation, producing 16% of the world's electricity at the beginning of 1999. It has proven to be safe, reliable, economical and has only a minimal impact on the environment. Most of the world's energy consumption, however, is in the form of heat. The market potential for nuclear heat was recognized early. Some of the first reactors were used for heat supply, e.g. Calder Hall (United Kingdom), Obninsk (Russian Federation), and Agesta (Sweden). Now, over 60 reactors are supplying heat for district heating, industrial processes and seawater desalination. But the nuclear option could be better deployed if it would provide a larger share of the heat market. In particular, seawater desalination using nuclear heat is of increasing interest to some IAEA Member States. In consideration of the ...

403

Control of anodic passivation systems  

Energy Technology Data Exchange (ETDEWEB)

A method is described of controlling an anodic protection system in a heat exchanger comprising: (a) installing at least one cathode within the heat exchanger, at least one cathode being aligned with the longitudinal axis of the heat exchanger and extending substantially along the length of the heat exchanger; (b) installing a first reference electrode within and at one end of the heat exchanger, the first reference electrode having a first controller having a set point for control and a power supply having an output creating an electrical potential between at least one cathode and the heat exchanger; (c) measuring the electrical potential of the heat exchanger with the first reference electrode; (d) operating the first controller in response to measurements made by the first reference electrode to change the output of the power supply; (e) ...

1987-08-25

404

Competition advantage by utilizing the gross calorific value-high potential for the local heat supply; Wettbewerbsvorsprung durch Brennwertnutzung. Hohes Potential bei der Nahwaermeversorgung  

Energy Technology Data Exchange (ETDEWEB)

The gross calorific value (H{sub o}) is the amount of heat which is generated by total combustion of a type of fuel. It also includes that part of heat which is generated by steam from evaporated water contained in heating gas. In conventional heating boilers, this heat portion is not being utilized at all. To utilize the gross calorific value, it is necessary to extract from the exhaust gas the evaporation heat bound in steam and to return this to the heating system. This means that the exhaust gas has to be chilled by the return water of the heating system and condensed in suitable heat exchangers to well below the dew point. (orig.) [Deutsch] Waermelieferanten im Bereich der Nahwaermeversorgung koennen durch die Anwendung verfuegbarer und bewaehrter Brennwerttechnik ihre Kosten senken und einen ...

1999-01-01

405

Boiling heat transfer in a small horizontal rectangular channel  

Energy Technology Data Exchange (ETDEWEB)

Compact heat exchangers have traditionally found wide application in the transportation industry, where they are used as evaporators and condensers in vapor compression cycles for air conditioning and refrigeration. Such heat exchangers possess numerous attractive features including high thermal effectiveness, small size, low weight, design flexibility, and pure counterflow, and they can accommodate multiple streams. Today, there is a widespread interest in expanding the range of application of compact heat exchangers to include phase-change heat transfer in the process industries, among others. An overall objective of this effort is to provide the basis for establishing design technology in this area. In the present study, small channel flow boiling heat transfer was extended to a rectangular channel (4.06 {times} 1.70 mm) using refrigerant 12 (R-12). As with the circular tube ...

1993-08-01

406

Air-side performance of a parallel-flow parallel-fin (PF{sup 2}) heat exchanger in sequential frosting  

Energy Technology Data Exchange (ETDEWEB)

The thermal-hydraulic performance in periodic frosting conditions is experimentally studied for the parallel-flow parallel-fin heat exchanger, henceforth referred to as a PF{sup 2} heat exchanger, a new style of heat exchanger that uses louvered bent fins on flat tubes to enhance water drainage when the flat tubes are horizontal. Typically, it takes a few frosting/defrosting cycles to come to repeatable conditions. The criterion for the initiation of defrost and a sufficiently long defrost period are determined for the test PF{sup 2} heat exchanger and test condition. The effects of blower operation on the pressure drop, frost accumulation, water retention, and capacity in time are compared under the conditions of 15 sequential frosting cycles. Pressure drop across the heat exchanger and overall heat transfer coefficient are quantified under frost conditions as ...

2010-09-15

407

The effect of the shear rate-dependent thermal conductivity of non-Newtonian fluids on the heat transfer in a pipe flow  

Science.gov (United States)

The present study investigates the effect of the shear rate-dependent thermal conductivity of non-Newtonian fluids on the heat transfer enhancement in a pipe flow. The constant heat flux as thermal boundary condition was adopted in the thermally developed region. The present analytical results show the heat transfer enhancement over those of a shear rate-independent thermal conductivity fluid. The heat transfer coefficient ratio (h/h{sub 0}) linearly increase with the non-dimensional average velocity difference which is the product of the shear rate-dependence of the thermal conductivity and wall-shear rate.

1996-09-01

408

Nonlinear dynamics of heat transfer enhancement using eddy promoters  

Science.gov (United States)

This investigation concerns the nonlinear dynamics of heat transfer from a surface using an upstream eddy promoter. A numerical model is developed for the coupled fluid flow and heat transfer process based on a modified MacCormack scheme. Numerical simulations are carried out to determine the response and heat transfer enhancement due to the promoter. The average heat transfer from a cavity floor is seen to be increased by a factor of approximately five over the unpromoted'' flow. Another interesting feature of the study is the nonlinear viscous flow dynamics from the cylinder-wall interaction which differ significantly from the familiar cylinder-free stream patterns.

1994-02-01

409

Nonlinear dynamics of heat transfer enhancement using eddy promoters  

Energy Technology Data Exchange (ETDEWEB)

This investigation concerns the nonlinear dynamics of heat transfer from a surface using an upstream eddy promoter. A numerical model is developed for the coupled fluid flow and heat transfer process based on a modified MacCormack scheme. Numerical simulations are carried out to determine the response and heat transfer enhancement due to the promoter. The average heat transfer from a cavity floor is seen to be increased by a factor of approximately five over the unpromoted'' flow. Another interesting feature of the study is the nonlinear viscous flow dynamics from the cylinder-wall interaction which differ significantly from the familiar cylinder-free stream patterns.

1994-02-01

410

Lack of oscillations in Dual-Phase-Lagging heat conduction for a porous slab subject to imposed heat flux and temperature  

Energy Technology Data Exchange (ETDEWEB)

This study shows that the physical conditions necessary for thermal waves to materialize in Dual-Phase-Lagging porous media conduction are not attainable in a porous slab subject to a combination of constant heat flux and temperature (Neumann and Dirichlet) boundary conditions. It is demonstrated that the approximate equivalence between Dual-Phase-Lagging (DuPhlag) heat conduction model and the Fourier heat conduction in porous media subject to Lack of Local Thermal Equilibrium (La Lotheq) that suggested the possibility of thermal oscillations and resonance reveals a condition that cannot be fulfilled because of physical constraints. (author)

2005-07-01

411

Heat transfer equipment design  

Energy Technology Data Exchange (ETDEWEB)

A comprehensive presentation is made of state-of-the-art configurations and design methodologies for heat transfer devices applicable to industrial processes, automotive systems, air conditioning/refrigeration, cryogenics, and petrochemicals refining. Attention is given to topics in heat exchanger mechanical design, single-phase convection processes, thermal design, two-phase exchanger thermal design, heat-transfer augmentation, and rheological effects. Computerized analysis and design methodologies are presented for the range of heat transfer systems, as well as advanced methods for optimization and performance projection.

1988-01-01

412

Heat rejection system  

Energy Technology Data Exchange (ETDEWEB)

A cooling system for rejecting waste heat consists of a cooling tower incorporating a plurality of coolant tubes provided with cooling fins and each having a plurality of cooling channels therein, means for directing a heat exchange fluid from the power plant through less than the total number of cooling channels to cool the heat exchange fluid under normal ambient temperature conditions, means for directing water through the remaining cooling channels whenever the ambient temperature rises above the temperature at which dry cooling of the heat exchange fluid is sufficient and means for cooling the water. 5 figs.

1980-01-22

413

Borehole heat store design optimization. The SmartStore model  

Energy Technology Data Exchange (ETDEWEB)

The SmartStore model was developed to determine the optimum design of borehole heat stores as a function of different design parameters. The optimum design is defined as the design that achieves the storage task with a minimum annual storage cost. The annual storage cost is the sum of annual costs of investment, operation, maintenance and heat loss. The PC-model has a user-friendly lay-out and gives a fast pre-design of borehole heat stores. In this article the model is briefly described. It is also shown that the technical design of the store is influenced by varying technical properties of the storage volume, but also by the cost of heat. (orig.)

1994-12-31

414

Analysis of laminar flow and heat transfer in the entrance region of an internally finned concentric circular annular duct  

Energy Technology Data Exchange (ETDEWEB)

The concentric circular annular duct is a common geometry in many fluid flow and heat transfer devices. For the purpose of heat transfer augmentation, fins are often employed in the annular region, and such finned ducts find wide application in compact heat exchangers (5, 6). The analysis of flow and heat transfer in this geometry is, therefore, quite important from an engineering standpoint. For fully developed conditions, the problem has already been analyzed (7-10). However, no results are available for the developing flow in the entrance region. It is with this latter problem that the present paper is concerned.

1987-05-01

415

Analysis of a bayonet tube heat exchanger  

Energy Technology Data Exchange (ETDEWEB)

This paper details the design, construction and testing of a bayonet tube heat exchanger for use in the process industry and potentially as part of an externally fired combined cycle. Detailed analysis of the system has been undertaken, in particular on the tube side. The data is reported in terms of temperature, pressure, heat gain and heat exchanger effectiveness, over a range of Reynolds numbers and shell side mixture ratios. Much of the heat gained by the tubes is in the annular flow of the bayonet tube. Overall the effectiveness of this system could exceed 70%. (Author)

2001-01-01

416

Heat pipe cooled piston - feasibility study  

Energy Technology Data Exchange (ETDEWEB)

This study assesses the feasibility of the so-called heat pipe technique for cooling the piston of a mediumspeed diesel engine and is part of a research project 'EVE HPD, Extreme Value Engine Tests with High Power Density' carried out by HUT Internal Combustion Engine Laboratory. Diesel engines are being developed to give greater power from a given cylinder swept volume, which means higher temperatures in combustion chamber. The traditional oil cooling cannot be used beyond certain temperature level. Heat pipe technology could provide one solution to the cooling problem. The general properties, principles of operation, and structures of different types of heat pipes are described. Working fluids and container materials of heat pipes are discussed. The operation limitations of heat pipes are studied, especially, the limitations of a reciprocating ...

2004-07-01

417

Tomographic measurements of carbon monoxide temperature and concentration in a Bunsen flame using diode laser absorption  

Energy Technology Data Exchange (ETDEWEB)

Temperature and concentration profiles of CO in a laminar, axisymmetric, premixed methane-air Bunsen flame are measured using line-of-sight diode laser absorption spectroscopy and computer tomographic (CT) reconstruction. Absorption spectra for P(20) (v=2<-1) and P(27) (v=1<-0) vibrotational transitions of CO were measured at 21 evenly spaced positions over a 1.33 cm span for a 1.3 cm radius flame. CT reconstruction algorithm was based on Fourier convolution. The tomographically reconstructed normalized transmission profiles derived from absorption spectra, in conjunction with a quantum mechanical model for vibrotational behavior of CO, yielded both temperature and concentration profiles. The Bunsen flame had 3 distinct zones: an inner rich-premixed flame zone, an outer non-premixed flame zone and an unburnt core region. The reconstructed temperature profile showed that the core region temperature was close to ambient ...

1993-12-01

418

Spectroscopic characterization of alkane radical cations: Pt. 1  

International Nuclear Information System (INIS)

Radical cations of various 3-methylalkanes (C_6-C_1_4) have been produced and stabilized by #gamma#-irradiation of the corresponding neutral compounds in saturated chlorofluorocarbon and perfluorocarbon matrices at 77 K. The perfluorocarbon matrices appeared more suitable for studies of the lighter radical cations, whereas the chlorofluorocarbon matrices were more suited for studies of the heavier radical cations; intermediary cations could be studied in both types of matrices. After irradiation, electronic absorptions associated with both the matrix and the alkane additive were observed. Pure spectra of the 3-methylalkane radical cations were obtained by difference spectrometry, after selective elimination of these cations by illumination. The electronic absorption spectra of the 3-methylalkane radical cations consist in all cases of a single broad absorption band. The spectral position of this band shifts to longer ...

1989-01-01

419

Measurement of the population densities in Gd atomic vapor using diode laser absorption spectroscopy in UV transitions  

International Nuclear Information System (INIS)

We report on the ultraviolet laser absorption spectroscopy of atomic Gd at 394-554 nm where two transition lines are place very closely by using a frequency-doubled beam of external-cavity diode laser (ECDL). One is from 999.121 to 26337.071 cm-1 and the other from 0 to 25337.755 cm-1. If two transition lines are placed closely within a continuous fine tuning range, the real-time measurement of the atomic excitation temperature is possible without any significant time consumption because at least two transition lines originating from different low-lying energy levels need to be investigated for the Boltzmann-plot. Since the spectral difference between the two transitions is only about 0.195 cm-1 (5.85 GHz), it is possible to record both the absorption spectra simultaneously as shown in Fig. 1. But the transition probabilities (or oscillator strengths) of these lines have not been measured accurately yet to the best of our knowledge. We report ...

2003-11-07

420

Gastrointestinal absorption of lead (/sup 203/Pb) in chicks: influence of lead, calcium, and age  

Energy Technology Data Exchange (ETDEWEB)

The present study was designed to investigate, in more detail, the mechanism of lead transport by the gastrointestinal tract and particularly the similarities or dissimilarities between lead and calcium in this process. The absorption of these metals was determined in 3-week-old white Leghorn cockerels, raised on a commercial diet or special diets, using an in vivo ligated loop procedure. The dose administered into the loop usually contained 0.5 ..mu..Ci /sup 203/Pb (and/or 0.1 ..mu..Ci /sup 47/Ca), 0.01 mM lead acetate (and/or 1 mM CaCl/sub 2/) in 0.5 ml of 0.15 M NaCl, pH 6.5. It was shown that lead is rapidly taken up by the intestinal tissue, and only slowly transferred into the circulation whereas calcium, also accumulated rapidly by the tissue, is rapidly released from the tissue in the serosal direction. The absorption processes of these cations show similar responses to various experimental conditions (low calcium intake, age of the ...

1981-10-01

421

Use of solar assisted geothermal heat pump and small wind turbine systems for heating agricultural and residential buildings  

Energy Technology Data Exchange (ETDEWEB)

The main objective of the present study is twofold: (i) to analyze thermal loads of the geothermally and passively heated solar greenhouses; and (ii) to investigate wind energy utilization in greenhouse heating which is modeled as a hybrid solar assisted geothermal heat pump and a small wind turbine system which is separately installed in the Solar Energy Institute of Ege University, Izmir, Turkey. The study shows 3.13% of the total yearly electricity energy consumption of the modeled system (3568 kWh) or 12.53% of the total yearly electricity energy consumptions of secondary water pumping, brine pumping, and fan coil (892 kWh) can be met by using small wind turbine system (SWTS) theoretically. According to this result, modeled passive solar pre heating technique and combined with geothermal heat pump system (GHPS) and SWTS can be economically preferable to the conventional space ...

2010-01-15

422

Study of solution for issues of an optimum operating plan in heat storing system; Chikunetsu system ni okeru saiteki un`yo keikaku mondai no kaiho ni taisuru ichikosatsu  

Energy Technology Data Exchange (ETDEWEB)

An approximate solution was proposed in which a sensitivity analysis by the storage and release of heat was performed for the subject issues and in which an operating method was thereby determined for the equipment constituting the system by means of a linear programming. Accordingly, a heat storage type energy supply system for a district cooling and heating was taken up as a concrete object to be examined. This system consisted of a gas turbine generator, initial power receiving equipment, gas boiler, electric heat pump for ice heat storage, cooling tower, heat exchanger, steam absorbing refrigerating machine, ice heat storage tank, cold and warm water heat storage tank, etc. As a result of comparison between the proposed method and the resolving method, the former showed -0.92 to 2.58% in the increase in the operating ...

1996-02-01

423

Study of heat rejection mechanism of a direct-injection diesel engine. 1st Report. Characteristics of local heat flux; Study of heat reinjection mechanism of a direct-injection diesel engine. 1. Characteristics of local heat flux  

Energy Technology Data Exchange (ETDEWEB)

Experimental investigations are being conducted on a single-cylinder direct-injection diesel engine to examine the transient heat transfer characteristics. Transient temperature data from stationary locations in the piston and cylinder head were used as the basis for determining the transient heat flux rates. Transient surface temperature was measured using the thin film thermocouples. At first, the transient heat flux rates calculated from the analysis method used in this paper were compared with the results from FEM. The results showed good agreement. Using this analysis method, the transient heat flux rates were calculated. The tests were performed at 1200 rpm with constant air flow. The parameters that were varied included the fuel rate and injection timing. Based on these results, the present paper discusses the mechanism of heat rejection in a direct-injection diesel engine. 8 ...

1997-09-25

424

Studies on improvement of heat transfer characteristics in high temperature heat exchangers, (1)  

International Nuclear Information System (INIS)

Reported in this paper are the theoretical and experimental studies, with regard to the effects of radiation between walls, conducted for the improvement of heat transfer characteristics of the circular duct in high temperature heat exchangers that operate through the medium of non-radiating gases at around 1,000"0C. To study the fundamental performance of the heat transfer augmentation, the experiment was carried out using a double tube at temperatures up to 900"0C. The outer tube in a double tube was selectively heated so as to give a uniform heat flux selected of 6.5 x 10"3 and 4.6 x 10"4 kcal/m"2.h, while the inner tube was used as a radiating surface to impart the radiation heat transmitted from the outer tube. Selectively preheated air was caused to flow in an annular passage at an inlet temperature selected within 100"0C to 400"0C and with the Reynolds ...

1978-01-01

425

Heating and cooling with geothermal energy: trends and accomplishments; Solutions de chauffage et de climatisation utilisant l`energie geothermique: tendances et realisations  

Energy Technology Data Exchange (ETDEWEB)

Recent developments in heat pump technology have made geothermal-based heat exchange systems particularly well-suited for the heating and cooling needs of buildings even in cold climates. The principles of geothermally-coupled heat pump heating and cooling systems were presented. Results of an in-situ study conducted by Hydro-Quebec on the efficiency of the geothermal heat pump system installed at the Saint-Hyacinthe professional school were summarized. This investigation was meant to be a case study of the applicability of these new technologies to the needs of the Quebec market. After the first year of service, the Saint-Hyacinthe system clearly demonstrated its cost effectiveness over conventional systems. It was predicted that geothermal heat pump systems will gain in popularity in Quebec because they can fully meet the ...

1996-03-01

426

Heat transfer in parallel plate duct with a sinusoidal wave plate uniaxially inserted (1st). Effect of wave length on heat transfer augmentation  

Energy Technology Data Exchange (ETDEWEB)

High-performance heat transfer augmentation methods applicable in the forced convection field of heat exchangers include a method which requires no external drive means, such as the insertion of a turbulence augmentation object into the flow passage and the use of a wave-shaped flow passage, but disturbs the main stream of flow to raise the heat transportation effect thereby to augment heat transfer in the flow passage. The heat transfer characteristics and thermal performance ratio achieved when sinusoidal-shape plates are inserted instead of augmentation objects, such as cylinders, with a high shape-induced resistance were studied. As a result, the relationship between the resistance coefficient, average Nusselt number, heat transfer coefficient, and pitch was clarified. It has been revealed that the use of eddies with a large gap flow and recirculation area ...

1988-09-01

427

Ground source heat for heat pumps; Erdgekoppelte Waermequellen fuer Waermepumpen  

Energy Technology Data Exchange (ETDEWEB)

Under the new name of ``geothermal heat pump``, ground-source heat pumps are currently high in demand in Northern America. In sectors characterized by heating and cold air demand, their advantages can be exploited to the full. For Germany, the end-use-energy substitution potential of geothermal heat pumps has been estimated at 1310-1470 PJ annually. Whether this potential can actually be exploited depends essentially on the development of energy prices, but also on the resourcefulness of plant and heat pump manufacturers in upgrading and cheapening geothermal heat pumps. (orig./RHM) [Deutsch] Unter der neuen Bezeichnung `Geothermal Heat Pump` erlebt die erdgekoppelte Waermepumpe z.Zt. in Nordamerika einen Verbreitungsschub. In dem durch Heiz- und Kuehlbedarf charakterisierten Umfeld kann sie Ihre Vorteile voll nutzen. Fuer Deutschland kommt ...

1996-12-31

428

Effect of coal rank and mineral matter on gasification reactivity of coal char treated at high temperature; Netsushorishita sekitan char no gas ka tokusei ni taisuru tanshu oyobi kobutsushitsu no eikyo  

Energy Technology Data Exchange (ETDEWEB)

In the wide range from brown coal to anthracite, an investigation was made of effects of heat treatment on physical/chemical properties and of coal rank dependence. For the experiment, 12 kinds of coal samples were used, and for heat treatment, the fluidized bed heated by the electric furnace and the infrared-ray gold image furnace were used. To examine characteristics of the heat-treated coal char, conducted were oxygen gasification, TPD measurement, XRD measurement, alkali metal measurement, and pore distribution measurement. The following were obtained from the experiment. The gasification reaction rate of the char heat-treated in the temperature range between 900{degree}C to 1700{degree}C decreases with a rise of the temperature of heat treatment, and the degree of decrease in the rate depends on coal rank. The order of gasification rate between coal ranks ...

1996-10-28

429

Core Heat Transfer Model Validation of the TASS/SMR-S Code using the Bennett's Test  

International Nuclear Information System (INIS)

The SMART (System-integrated Modular Advanced ReacTor) which is a 330 MWt advanced integral PWR was developed by the KAERI (Korea Atomic Energy Institute) for electricity generation and seawater desalination. A thermal hydraulic evaluation and analysis of the SMART is performed by the TASS /SMR-S (Transient And Setpoint Simulation/System integrated Modular Reactor-Safety). The TASS/SMR-S code has various models reflecting the design features of the SMART such as the drift flux model, the core models (core power and core heat transfer model), the component models, and the specific models. One of the core models is the core heat transfer model. The role of this model is to calculate the heat flux and radial temperature profiles at a fuel rod surface using the relevant heat transfer correlations for all of the heat transfer modes. Also it is modeled to meet the requirements of the 10 ...

2010-10-01

430

Comparative performance of two types of evacuated tube solar collectors in a residential heating and cooling system. The progress report  

Science.gov (United States)

Two types of evacuated tube solar collectors have been operated in space heating, cooling and domestic hot water heating systems in Colorado State University Solar House I. An experimental collector from Corning Glass Works supplied heat to the system from January 1977 through February 1978, and an experimental collector from Philips Research Laboratory, Aachen, which is currently in use, has been operating since August 1978. A flat absorber plate inside a single-walled glass tube is used in the Corning design, whereas heat is conducted through a single glass wall to an external heat exchanger plate in the Philips collector. In comparison with conventional flat-plate collectors, both types show reduced heat losses and improved efficiency. For space heating and hot water supply in winter, the solar delivery efficiency of the Corning collector ...

1979-01-01

431

CFD simulation of flow distribution in the header of plate-fin heat exchangers  

Energy Technology Data Exchange (ETDEWEB)

The flow distribution through a plate-fin heat exchanger is studied by using a computational fluid dynamics (CFD) code, FLUENT. The flow distribution through any heat exchanger affects its performance. In designing a heat exchanger, it is assumed that the fluid is uniformly distributed through the heat exchanger core. In practice, however, it is impossible to distribute fluid uniformly, because of an improper inlet configuration, imperfect design, and a complex heat transfer process. The CFD simulation of the flow distribution in the header of a conventional plate-fin heat exchanger is presented. It is found that the flow maldistribution is very serious in the y-direction of the header. A modified header is proposed and simulated using CFD. The modified header configuration has a more uniform flow distribution than the conventional header configuration. Hence, ...

2007-10-15

432

Augmentation of heat transfer in a tube with an oscillating thin plate. Shindohen sonyu ni yoru enkannai netsudentatsu sokushin  

Energy Technology Data Exchange (ETDEWEB)

An attempt is made to augment the heat transfer efficiency by means of inserting an oscillating thin plate into a tube of the shell and tube heat exchanger. However, the heat transfer augmenting mechanism has not been fully explained. To elucidate this heat transfer augmenting mechanism, an investigation was given on the heat transfer characteristics of a tube inlet at its preliminary run area when a double-hinged oscillating thin plate is inserted in the inlet. As a result of the experiment, the heat transfer augmentation in the tube as a result of inserting the double-hinged oscillating thin plate was found effective when the preliminary inlet run area is treated as the object. However, in comparison of the effect with the heat transfer in a fully developed turbulent region, it was {eta}- 1. The result thus obtained explains that no ...

1991-09-01

433

Kelvin-day function for climatic solar heating design  

Energy Technology Data Exchange (ETDEWEB)

A method of Kelvin-day function for climatic solar heating design is presented. The long term temperature distribution is used to find the solar fraction for building heating. A solar heating system is considered to provide heat needed up to an auxiliary heater cut-in temperature which is determined by both heat gain of solar heating system and overall heat loss coefficient of the building. The amount of auxiliary heat needed is calculated from a Kelvin-day value at this cut-in temperature. The cut-in temperature will change from different solar heating system designs, and the Kelvin-day value at this cut-in temperature will be varied. By using the numerical curve-fitting method, the Kelvin-day value at any temperature base can be expressed into a second order algebraic equation, thus, the whole data ...

1981-01-01

434

Comparison of central heating with district heating and small-scale cogeneration. Vergelijking van centrale verwarming met stadsverwarming en kleinschalige warmtekoppeling; Energiebesparing, emissies en financiele resultaten  

Energy Technology Data Exchange (ETDEWEB)

Three systems for the heat supply in the built environment have been compared for the costs, the energy consumption and emissions of CO{sub 2}, NO{sub x} and SO{sub 2}. The heating systems compared are based on central heating boilers, district heating systems in combination with combined steam and gas turbine cycles, and heating by means of several gas engines. From the results it appears that the boilers demand the lowest investments. The district heating systems are more expensive. Both heating systems, however, show considerable savings of energy (55 to 70%). The exploitation costs depend strongly on the fuel price scenarios used and the assumptions with regard to interest and inflation. The emissions of CO{sub 2} are also considerably lower for both combined heat and power generating systems. The use of gas engines ...

1991-07-01

435

A desiccant dehumidifier for electric vehicle heating  

Energy Technology Data Exchange (ETDEWEB)

Vehicle heating requires a substantial amount of energy. Engines in conventional cars produce enough waste heat to provide comfort heating and defogging/defrosting, even under very extreme conditions. Electric vehicles (EVs), however, generate little waste heat. Using battery energy for heating may consume a substantial fraction of the energy storage capacity, reducing the vehicle range, which is one of the most important parameters in determining EV acceptability. Water vapor generated by the vehicle passengers is in large part responsible for the high heating loads existing in vehicles. In cold climates, the generation of water vapor inside the car may result in water condensation on the windows, diminishing visibility. Two strategies are commonly used to avoid condensation on windows: windows are kept warm, and a large amount of ambient air is introduced in ...

1996-09-01

436

Thermal gradient humidification-dehumidification desalination system  

Energy Technology Data Exchange (ETDEWEB)

A solar energy desalination process utilizing solar radiation directly for the evaporation of salt water is described. Ambient air takes on water vapor as the air passes through an evaporative medium. It is then directed between a saline water-covered, solar absorbing surface and a solar collecting housing. The resulting heated and moisture-saturated air is cooled in a heat exchange means where condensation of fresh water occurs. Simultaneously, cool salt water is utilized as the cooling water in the heat exchange means, and takes on the heat of condensation given up by the condensing vapor. The heated salt water from the heat exchange means is partially directed over the solar absorbing surface, and at least a portion of it is also directed to wet the evaporative medium. Several optional sub-processes are described for operation of the system during periods of ...

1982-12-14

437

Thermal energy storage system with stearic acid as phase change material  

Energy Technology Data Exchange (ETDEWEB)

A simple tube-in-tube heat exchanger system for thermal energy storage employing stearic acid as PCM has been investigated. The performance and heat transfer characteristics of such a system were studied. Phase transition temperature range and times were measured and the speed of the phase transition front was computed. The melting front was found to move in the radial direction inward as well as in the axial direction from the top toward the bottom of the phase change material PCM tube. The speed of the melting front is enhanced by a convection heat transfer mechanism in the melted PCM. The heat transfer rate and, consequently, phase transition time can be altered by changing the water inlet temperature to the heat exchanger. In addition, a faster phase transition is realized by placing the heat exchanger in a horizontal position rather than a vertical one. ...

1994-10-01

438

The influence of wall deposits on heat transfer in combustion engines. Einfluss von Wandablagerungen auf den Waermeuebergang im Verbrennungsmotor  

Energy Technology Data Exchange (ETDEWEB)

The experimental survey about the heat transfer between the working fluid and the combustion chamber wall with a direct injection diesel engine has shown the production of a soot layer with increasing loads on the combustion chamber wall. Because the combustion process of methanol occurs without the formation of wall deposits, the same engine spark ignitioned with methanol at the same conditions has shown a higher heat transfer coefficient. Because the heat losses do not only depend on the heat transfer coefficient but also on the driving temperature difference between the working fluid and the combustion chamber wall, the methanol engine with corresponding process management showed lower heat losses than the diesel engine at nearly the same load. (orig./HW)

1994-04-01

439

Solar thermal aircraft  

Energy Technology Data Exchange (ETDEWEB)

A solar thermal powered aircraft powered by heat energy from the sun. A heat engine, such as a Stirling engine, is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller. The heat engine has a thermal battery in thermal contact with it so that heat is supplied from the thermal battery. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the ...

2007-09-18

440

Process for repairing a cryogenic heat exchanger  

International Nuclear Information System (INIS)

The patent describes a method for repairing leakage-causing cracks and fissures in a cryogenic heat exchanger. It comprises: reducing the interior pressure of the heat exchanger to a level which does not exceed the external pressure upon the hear exchanger while maintaining the temperature of the heat exchanger at a low level relative to the ambient external temperature; applying a curable liquid filler composition to the surface of the heat exchanger proximal the leakage site for seepage into the cracks and fissures located at the leakage. The composition upon a relatively short period of cure at low temperature forming a solid material which fills the cracks and fissures; curing the filler composition; and, applying a sealant composition to the surface of the heat exchanger at the filled leakage site. The sealant composition having long-term sealing performance under cyrogenic ...

1987-10-13

441

Numerical heat transfer studies of the fatty acids for different heat exchanger materials on the performance of a latent heat storage system  

Energy Technology Data Exchange (ETDEWEB)

Theoretical investigations of fatty acids as a phase change material (PCM) for energy storage system have been conducted in this study. The selected fatty acids were capric acid, lauric acid, myristic acid, palmitic acid and stearic acid. For the two-dimensional simulation model based on the enthalpy approach, calculations have been made for the melt fraction with conduction only. Glass, stainless steel, tin, aluminium mixed, aluminium and copper were used as heat exchanger materials in the numerical calculations. Theoretical results show that capric acid was found good compatibility with latent heat storage system. The large value of thermal conductivity of heat exchanger materials did not make significant contribution on the melt fraction. (author)

2005-11-01

442

Numerical and experimental investigation of shellside characteristics for RODbaffle heat exchanger  

Energy Technology Data Exchange (ETDEWEB)

RODbaffle heat exchanger is a kind of shell-and-tube heat exchanger with eminent performance. Because of the characteristics of tube bundle support structure, fluid flow on shellside is longitudinal and periodical, and fluid flow is of symmetry in landscape orientation. According to the fluid flow characteristics on shellside and ignoring the impact of inlet, outlet and shell wall, a periodic flow unit duct was taken as the simplified model of the shellside to perform numerical simulation by using CFD code, FLUENT. It was found that the both errors in magnitude of the main fluid velocities and heat transfer coefficients between results of simulation and that of experiment or correlations are less than 10%, and the errors of pressure drop between simulation and correlation are no more than 20%. The detailed characteristics and relation of fluid flow and heat transfer on shellside of the RODbaffle ...

2008-05-15

443

MINERGIE modules: heat pump - heat pump/solar - wood - wood/solar; Minergie-Module Waermepumpe - Waermepumpe/Solar - Holz - Holz/Solar  

Energy Technology Data Exchange (ETDEWEB)

This research report for the Swiss Federal Office of Energy (SFOE) presents the results of a project that examined the feasibility of setting up 'MINERGIE' low-energy-consumption module standards for the production of heat in small residential buildings. The aims of the standards and the basic idea behind the MINERGIE-modules are discussed. The concepts of the modules for heat pumps and wood-fired heating systems and their combination with solar installations are examined, as are their areas of application. The requirements placed on the modules are listed. System concepts, including simple schematics for typical installations, are presented for wood-log, wood-chippings and pellets-fired systems as well as for ground-loop and air-water heat pump systems as well as their solar-aided counterparts. The results of cost-benefit analyses are presented and questions regarding system guarantee ...

2005-07-01

444

Human climatic comfort within enclosing walls with varying strengths of infrared radiation reflection  

Energy Technology Data Exchange (ETDEWEB)

An experiment lasting a number of hours was carried out with 6 men under standardised climate chamber conditions to find out to what extent wallpaper that reflects about 65-75% in the infra-red range by comparison with normal wallpaper that reflect only 3-5% of heat, has measurable positive effects on the thermoregulation of the human body and the human sensation of temperature. The measurements of skin temperature and heat flow intensity in the deeper areas of the body and the periphery, and metabolic heat conversion measurements (indirect calorimetry) confirm that infra-red reflection of the heat irradiated from the body lead to a measurable heat recovery on the body surface with a reduction of metabolic conversion. It was proved that it is possible to reduce the average room temperature by up to 4 K whilst maintaining the same degree of thermal comfort, which corresponds to a 20% ...

1985-06-01

445

Horizontal ground coupled heat pump: Thermal-economic modeling and optimization  

Energy Technology Data Exchange (ETDEWEB)

The modeling and optimizing processes of a Ground Coupled Heat Pump (GCHP) with closed Horizontal Ground Heat eXchanger (HGHX) are presented in this paper. After thermal modeling of GCHP including HGHX, the optimum design parameters of the system were estimated by minimizing a defined objective function (total of investment and operation costs) subject to a list of constraints. This procedure was performed applying Genetic Algorithm technique. For given heating/cooling loads and various climatic conditions, the optimum values of saturated temperature/pressure of condenser and evaporator as well as inlet and outlet temperatures of the water source in cooling and heating modes were predicted. Then, for our case study, the design parameters as well as the configuration of HGHX were obtained. Furthermore, the sensitivity analysis of change in the total annual cost of the system and optimum design parameters ...

2010-12-15

446

High thermal load receiving heat plate  

Energy Technology Data Exchange (ETDEWEB)

The present invention concerns a high thermal load heat receiving plate such as a divertor plate of a thermonuclear device. The high thermal load heat receiving plate of the present invention has a cooling performance capable of suppressing the temperature of an armour tile to less than a threshold value of the material against high thermal loads applied from plasmas. Spiral polygonal pipes are inserted in cooling pipes at a portion receiving high thermal loads in the high temperature load heat receiving plate of the present invention. Both ends of the polygonal pipes are sealed by lids. An area of the flow channel in the cooling pipes is thus reduced. Heat conductivity on the cooling surface of the cooling pipes is increased in the high thermal load heat receiving plate having such a structure. Accordingly, temperature elevation of the armour tile can be suppressed. (I.S.).

1993-09-28

447

Heat loss from an open cavity  

Energy Technology Data Exchange (ETDEWEB)

Cavity type receivers are used extensively in concentrating solar thermal energy collecting systems. The Solar Total Energy Project (STEP) in Shenandoah, Georgia is a large scale field test for the collection of solar thermal energy. The STEP experiment consists of a large field array of solar collectors used to supplement the process steam, cooling and other electrical power requirements of an adjacent knitwear manufacturing facility. The purpose of the tests, conducted for this study, was to isolate and quantify the radiative, conductive, and convective components of total heat loss, and to determine the effects of operating temperature, receiver angle, and aperture size on cavity heat loss. An analytical model for radiative heat loss was developed and compared with two other methods used to determine radiative heat loss. A proposed convective heat loss correlation, including ...

1995-12-01

448

Heat Transfer Characteristics of Tubular Thermal Reactor  

International Nuclear Information System (INIS)

Heat transfer augmentation based on the process intensification concept in heat exchangers and thermal reactors has received much attention in recent years, mainly due to energy efficiency and environmental considerations. The concept consists of the development of novel apparatuses and techniques that, compared to those commonly used today, are expected to bring dramatic improvements in manufacturing and processing, substantially decreasing equipment size, energy consumption, and ultimately resulting in cheaper, sustainable technologies. The objective of this paper was to investigate the heat transfer characteristics of tubular thermal reactor using static mixing technology. Glycerin and water were used as the test fluids and water was used as the heating source. The results for heat transfer rate were strongly influenced by tube geometry and flow conditions.

449

Fundamental study of heat transfer and flow situation around a spacer (in the case of a cylindrical rod as a spacer)  

International Nuclear Information System (INIS)

This paper describes the heat transfer augmentation and the flow situation around a single spacer (a cylindrical rod) on the heated surface of a parallel plate duct in order to examine basically the effects of the spacer in the fuel elements of a high temperature gas-cooled reactor. The ends of the cylindrical rod contact the upper and lower planes. A thermosensitive liquid crystal film is used to indicate the effective area for the heat transfer. The mean Nusselt number, which is estimated within the optional distance from the spacer to the downstream direction, peaks at a dimensionless distance of X/D = 1-3, and after that decreases gradually with the flow direction. The manner in which heat transfer corresponds to the flow situation is also examined. The horseshoe vortex, produced around the spacer, affects the wake and contributes to the increase of the local heat transfer. ...

1988-01-01

450

Full-scale model of cooling and heating system for JT-60 vacuum vessel  

Science.gov (United States)

A full-scale model of a rigid sectorial ring and a set of bellows which was covered with a temperature control layer and a coolant supply equipment was constructed to verify the adequacy of the heating and cooling system designed for JT-60. To cool and heat it effectively and to decrease the temperature differences among the various parts in the vacuum vessel, heater units and cooling pipes were located on the surface of the ring. The temperature control layer is to heat the vessel to 500/degree/sub //C within 70 hours and to maintain it at the temperature for 48 hours for simulating the state of bakeout. Subsequently the vessel is cooled down within about the same time as in heating. Prior to the series of tests, numerical analyses were performed to predict the cooling and heating efficiencies on the model and to examine the method of the temperature regulation.

1981-01-01

451

Condensation heat transfer in a steam-water stratified flow  

Energy Technology Data Exchange (ETDEWEB)

Fundamental phenomena of condensation heat transfer at a steam-water interface have been studied related to the thermo-hydrodynamics of the emergency core cooling system for light water reactors. In this study temperature fluctuations near the interface and in the liquid phase were measured using fine thermocouples for a saturated steam-subcooled water co-current stratified two-phase flow in a nearly horizontal rectangular channel, and heat transfer coefficients were determined experimentally. The values of the condensation heat transfer coefficients in this experiment are from 6 to 40 kW/m{sup 2}K. In the regions of high Reynolds numbers, as the steam Reynolds numbers become larger, the average interfacial heat transfer coefficients tend to increase. The corelations of Nusselt numbers were obtained from the heat transfer data. (author)

1999-07-01

452

Condensation heat transfer in a steam-water stratified flow  

International Nuclear Information System (INIS)

Fundamental phenomena of condensation heat transfer at a steam-water interface have been studied related to the thermo-hydrodynamics of the emergency core cooling system for light water reactors. In this study temperature fluctuations near the interface and in the liquid phase were measured using fine thermocouples for a saturated steam-subcooled water co-current stratified two-phase flow in a nearly horizontal rectangular channel, and heat transfer coefficients were determined experimentally. The values of the condensation heat transfer coefficients in this experiment are from 6 to 40 kW/m"2K. In the regions of high Reynolds numbers, as the steam Reynolds numbers become larger, the average interfacial heat transfer coefficients tend to increase. The corelations of Nusselt numbers were obtained from the heat transfer data. (author)

1999-04-19

453

Comparison of stomach contents and condition of two catfish species living at ambient temperatures and in a heated discharge  

International Nuclear Information System (INIS)

The lower condition factors for two catfish species in water heated by effluents from APCo's Glen Lyn, Virginia plant as compared to control areas probably is not due to lack of food as evidenced by macroinvertebrate sampling and the fact that only 4.3 percent of the catfish stomachs were empty. Results suggested that young-of-the-year channel catfish were nonselectively eating food organisms present at both control and heated stations. The difference between stomach contents of flatheat catfish from the heated site and fauna available at that site indicated that fish were either moving out of the heated area to feed or were selectively feeding on organisms (particularly mayflies) which were in the substrate or drifted into the heated area. Stomach contents of the two species and distribution and abundance of the macroinvertebrate benthos community are detailed.

454

C-E critical heat flux. Critical heat flux correlation for C-E fuel assemblies with standard spacer grids. Part 1. Uniform axial power distribution  

International Nuclear Information System (INIS)

The report presents the results of experimental studies conducted to provide a description of the conditions which lead to the occurrence of critical heat flux (CHF), in Combustion Engineering (C-E) fuel assemblies using the C-E standard spacer grid. A CHF correlation is presented which is based on CHF data obtained in tests with electrically heated rod bundles representative of the C-E 14 x 14 and 16 x 16 array fuel assemblies. The results reported are for a uniform axial heat flux distribution. The experiments were conducted in the Medium Pressure Heat Transfer Flow Loop at the Chemical Engineering Research Laboratories at Columbia University.

455

Boiling heat transfer of subcooled water in a horizontal rectangular channel. Observation of MEB and MEB generation; Kukeikan ryuronai no subcool futto netsu dentatsu. Kiho bisaika futto no kansatsu to hassei joken  

Energy Technology Data Exchange (ETDEWEB)

Forced convection boiling of subcooled water was performed in a horizontal rectangular channel with heated surface on the bottom. The experiment was conducted for heating surfaces, 10 mm, 20 mm and 40mm in length. Microbubble Emission Boiling, MEB, was observed in subcooled transition boiling and easy to be generated for the shorter heating surfaces. In higher flow velocity of subcooled water, MEB was generated at even lower subcooling. Stormy MEB was observed at both the higher subcooling and the higher flow velocity of water. In the stormy MEB, the heat flux rose up rapidly above CHF (Critical Heat Flux) with larger acoustic noise and vibration. (author)

1999-09-25

456

Approximate solutions to the Stefan problem with internal heat generation  

Energy Technology Data Exchange (ETDEWEB)

Using a quasi-static approach valid for Stefan numbers less than one, we derive approximate equations governing the movement of a phase change front for materials which generate internal heat. These models are applied for both constant surface temperature and constant surface heat flux boundary conditions, in cylindrical, spherical, plane wall and semi-infinite geometries. Exact solutions with the constant surface temperature condition are obtained for the steady-state solidification thickness using the cylinder, sphere, and plane wall geometries which show that the thickness depends on the inverse square root of the internal heat generation. Under constant surface heat flux conditions, closed form equations can be obtained for the three geometries. In the case of the semi-infinite wall, we show that for constant temperature and constant heat flux out of the wall conditions, the ...

2008-05-15

457

Application of Combined Enhanced Techniques for Design of Highly Efficient Air Heat Transfer Surface  

British Library Electronic Table of Contents (United Kingdom)

In order to reduce the size and cost of heat exchangers, an air-side wavy fin-and-tube heat transfer surface with three-row tubes needs to be replaced by two-row tubes with some appropriate enhancing techniques. The major purpose of the present paper is to search for such new structure by numerical simulation. First, longitudinal vortex generators of Delta-winglet type are tried. The influence of number and of arrangement of the winglets on the performance of the heat transfer surface is studied in detail. The numerical results show that the fin with two winglets aligned spanwise in the front and rear of each tube (Fin W6) has higher heat transfer capability than other enhanced structures with vortex generators, but it still unable to meet the heat transfer requirement. Then a combination ...

2012-01-01

458

Analysis of WITCH/LINER experiments on heat transfer between gas-agitated steel melt and vertical wall  

Energy Technology Data Exchange (ETDEWEB)

The analysis for the WITCH/LINER experiments was performed to investigate the heat transfer characteristics between the gas-agitated steel melt and the vertical surface. The applicability of heat transfer correlations for a gas-agitated fluid system was examined through the numerical analysis of the one-dimensional heat conduction taking into account the crust formation due to the solidification of the steel melt. The heat transfer correlation developed by Konsetov was modified for the application to fluids with low Prandtl number. The constant in the modified correlation was empirically found mainly through the comparison between the analysis and the experiments under conditions that a churn-turbulent two-phase flow regime was anticipated to form. The modified Konsetov correlation could predict the heat transfer characteristics observed through the experiments in an acceptable ...

1999-10-01

459

A fundamental study of the heat transfer and flow situation around a spacer  

International Nuclear Information System (INIS)

This paper describes the heat transfer augmentation and flow situation around a single spacer (a circular cylinder) on a heated surface in a parallel plate duct in order to examine basically the effects of the spacer in the fuel elements of a High Temperature Gas-cooled Reactor. A thermosensitive liquid crystal film was used to clarify the effective region of the heat transfer. The mean Nusselt number, which was estimated within arbitrary distance from the spacer to the downstream direction, took a peak at the dimensionless distance X/D = 1 #approx# 3, and after that decreased gradually with flow direction. How heat transfer corresponds to the flow situation is also examined. The horseshoe vortex, produced around the spacer, affects the wake and contributes to the increase of the local heat transfer. (author).

1986-01-01

460

Theoretical study of indoline dyes for dye-sensitized solar cells  

International Nuclear Information System (INIS)

Indoline dye sensitizers were designed and studied theoretically to increase molar extinction coefficients in the visible to near infrared region for solar-cell devices. To gain insight into dye sensitizers' structural, electronic, and optical properties, DFT/TDDFT calculations were performed on a series of dye sensitizers derived from the D149. The good agreement between the experimental and TDDFT calculated absorption spectra of the D149 sensitizer allowed us to provide a detailed assessment of the main spectral features of a series of dye sensitizers. Increase in the conjugation length resulted in a more red-shifted spectral response and less positive oxidation potential than that of the D149. The dye with the dimethylfluorene group showed stronger absorption bands due to a large dipole moment. The calculated dipoles for the dye series correlate well with the observed strong absorption bands of the electronic spectra. ...

2010-09-01

461

Technology concerning fibrous activated charcoal and its utilization  

Energy Technology Data Exchange (ETDEWEB)

Activated charcoal has so far taken a shape of particle or powder, but as the third activated charcoal, fibrous activated charcoal (ACF) has begun to be produced industrially. In comparison with the conventional activated charcoal, ACF has such characteristics as follows (1) its rate of absorption and desorption is very fast, (2) its specific area is large and it has high absorption performance, (3) it has wide absorption characteristics, and (4) its reactivation and reutilization are possible. In addition, because of its fibrous condition, it can be processed into compound materials of various shapes by utilizing the fiber processing technology. Furthermore, it can be combined with other functional fibrous material and used as multifunctional material. In this article, the production process, performance, characteristics and usage of ACF, which is an excellent absorbent as stated above, are outlined with a focus on the ...

1988-10-01

462

Report on the project on the researcher dispatch type international joint research survey. Feasibility study for digging up the seeds for international joint research; Kenkyusha hakengata kokusai kyodo kenkyu chosa jigyo hokokusho. Kokusai kyodokenkyu sizu hakkutsu no tameno FS chosa  

Energy Technology Data Exchange (ETDEWEB)

For the purpose of digging up themes of the joint research which develop the R and D in the industrial technology field in Japan to a new stage, researchers were sent to the world representing research institutes to conduct the research survey of 'Nano-structured carbon and hydrogen absorption' and 'Development of the creation technology of nano-porous materials.' As to the former, an experiment on electrochemical hydrogen absorption of carbon materials including nanotubes was conducted by researchers dispatched, but the large absorption amount was not observed. As to the latter, visits were paid to Fraunhofer Institute and the related facilities in Germany, Princeton University, MIT, GIT and Naval Research Laboratories in the U.S., Orleans University in France, AO Research Institute (bone repair study) in Switzerland, Cambridge University and University of Bristol in the U.K., etc., and ...

2001-03-01

463

PIXE analysis of GaAs and ZnSe  

Energy Technology Data Exchange (ETDEWEB)

The optoelectronic compounds of GaAs and ZnSe are difficult to analyze by PIXE (particle-induced X-ray emission) due to the strong absorption of the As and Se K{sub {alpha}} X-rays. As part of a program to investigate optoelectronic materials using ion beam techniques, we have explored the possibility of using the high sensitivity of PIXE to check these materials for stoichiometry and dopant concentrations. The K{sub {alpha}} X-ray intensity ratios of Ga to As and Zn to Se have been investigated using H beams of 0.5 to 2.5 MeV and He beams of 1.0 to 2.5 MeV. The variation in the X-ray intensity ratio with beam energy and target thickness is modelled in terms of the cross section for X-ray production and the absorption coefficients of the X-rays in the target. The results of this model show the experimental conditions that must be satisfied in order that the X-ray intensity ratios are not strongly affected by X-ray ...

1990-01-01

464

PIXE analysis of GaAs and ZnSe  

International Nuclear Information System (INIS)

The optoelectronic compounds of GaAs and ZnSe are difficult to analyze by PIXE (particle-induced X-ray emission) due to the strong absorption of the As and Se K_#alpha# X-rays. As part of a program to investigate optoelectronic materials using ion beam techniques, we have explored the possibility of using the high sensitivity of PIXE to check these materials for stoichiometry and dopant concentrations. The K_#alpha# X-ray intensity ratios of Ga to As and Zn to Se have been investigated using H beams of 0.5 to 2.5 MeV and He beams of 1.0 to 2.5 MeV. The variation in the X-ray intensity ratio with beam energy and target thickness is modelled in terms of the cross section for X-ray production and the absorption coefficients of the X-rays in the target. The results of this model show the experimental conditions that must be satisfied in order that the X-ray intensity ratios are not strongly affected by X-ray absorption; and ...

1989-06-01

465

Nomographs for H[sub 2]O-LiBr absorption-panel cooling systems  

Energy Technology Data Exchange (ETDEWEB)

Panel cooling of buildings offers energy savings over conventional space-cooling systems. We present a procedure for calculating the performance of H[sub 2]O-LiBr absorption-panel cooling systems, in which the evaporator is the panel itself. Nomographs have been developed for this approach. Under the conditions examined, the H[sub 2]O-LiBr absorption unit operates with a theoretical performance coefficient of about 90% and with a practically constant specific cooling capacity of 2394 kJ/kg H[sub 2]O. For common values of the parameters involved, the panel cooling power varies from 25 to 175 W/m[sup 2] and the cooling water mass-flow through the panel is 40-260 g/m[sup 2]h. The thermal power needed to drive the system varies from 27 to 200 W/m[sup 2] and the associated temperatures from 70 to 100[sup o]C; thus, the system may be operated on solar energy. (Author).

1992-11-01

466

Microwave absorption properties and infrared emissivities of ordered mesoporous C-TiO2 nanocomposites with crystalline framework  

International Nuclear Information System (INIS)

Ordered mesoporous C-TiO2 nanocomposites with crystalline framework were prepared by the evaporation-induced triconstituent co-assembly method. The products were characterized by XRD, TEM, N2 adsorption-desorption and TG. Their microwave absorption properties were investigated by mixing the product and epoxy resin. It is found that the peak with minimum reflection loss value moves to lower frequencies and the ordered mesoporous C-TiO2 nanocomposite possesses an excellent microwave absorbing property with the maximum reflection loss of -25.4 dB and the bandwidth lower than -10 dB is 6.6 GHz. The attenuation of microwave can be attributed to dielectric loss and their absorption mechanism is discussed in detail. The mesoporous C-TiO2 nanocomposites also exhibit a lower infrared emissivity in the wavelength from 8 to 14 ?m than that of TiO2-free powder. -- Graphical abstract: Ordered mesoporous C-TiO2 nanocomposite with crystalline framework ...

2010-12-01

467

Ionic liquids for post combustion CO{sub 2} absorption  

Energy Technology Data Exchange (ETDEWEB)

The use of ionic liquids for post combustion capture was discussed. Compared to other solvents, ionic liquids can be used in higher concentrations. Other advantages include the large variation in physical and chemical properties and the non measurable vapor pressure. In this study, 78 different ionic liquids were synthesized and the carbon dioxide absorption rate was measured. The most promising ionic liquids were produced and various tests were made to identify the most suitable absorption solvent. The vapor-liquid equilibrium curve was measured between 40 and 110 degrees C. Pilot plant tests with MEA and one selected ionic liquid test with 30 per cent MEA at the pilot plant at the EVNs Duernrohr Power Station in Lower Austria are running successfully with a capture performance of approximately 87 per cent. The experiments will provide a direct comparison of the energy demand and capture performance between the MEA and the ionic liquids.

2009-07-01

468

FT-IR spectroscopic studies of polycyclic aromatic hydrocarbons  

International Nuclear Information System (INIS)

Proper assessment of the hypothesis which correlates polycyclic aromatic hydrocarbons (PAHs) with the unidentified infrared emission bands requires additional experimental laboratory data. In order to address this need, thermal infrared emission studies were performed on a subset of PAHs suggested to be of astrophysical importance. It was proposed that infrared emission from interstellar PAHs occurs following absorption of an ultraviolet photon. Since energy transfer to the ground electronic state can be rapid for a species in which intersystem crossing is negligible, the emission spectrum may be viewed as resulting from an equilibrium vibrational temperature (Leger and d'Hendecourt, 1987). This has been the basis for using infrared absorption spectra to calculate the corresponding emission spectra at various temperatures. These calculations were made using room temperature infrared absorption coefficients instead of those ...

1990-04-01

469

Effect of vitamin C on copper retention in young men  

International Nuclear Information System (INIS)

Previous work suggests that supplemental ascorbic acid (AA) may inhibit intestinal copper absorption by stabilizing the less absorbable cuprous state. The authors studied copper absorption in healthy men (age 19-32) fed a constant diet with different amounts of ascorbic acid supplements. The 6 men were confined to a metabolic unit for the entire 14 week study. The basal diet consisted of a 7 day rotating menu which provided an average of 2.1 mg Cu/d and was adequate in all other nutrients except AA (5 mg/d). The basal diet was supplemented with either zero, 60, or 600 mg of AA daily, added to grape juice and consumed at each meal. All feces were collected. Blood was taken weekly for monitoring AA and copper status. Copper absorption was determined by both balance and "6"5Cu stable isotope techniques. As determined by fecal Cu excretion, varying intakes of AA between 0.1 to 10 times the RDA had no significant effect on ...

1986-04-13

470

Anisotropy in Magnetic Properties and Electronic Structure of Single Crystal LiFePO4  

Energy Technology Data Exchange (ETDEWEB)

We report the experimental and theoretical results on the anisotropies in the magnetic properties and x-ray absorption spectra of single-crystal LiFePO4. A mean-field theory is developed to explain the observed strong anisotropies in Lande g-factor, paramagnetic Curie temperature, and effective moment for LiFePO4 single crystals. The values of the in-plane nearest- and next-nearest-neighbor spin exchange (J1 and J2), interplane spin exchange (J{perpendicular}), and single-ion anisotropy (D), obtained recently from neutron scattering measurements, are used for calculating the Curie temperatures with the formulas derived from the mean-field Hamiltonian. It is found that the calculated Curie temperatures match well with that obtained by fitting the magnetic susceptibility curves to the modified Curie-Weiss law. For the polarized Fe K-edge x-ray absorption spectra of single-crystal LiFePO4, a different feature assignment for the 1s4p transition ...

2008-01-01

471

Absorption Features in Spectra of Magnetized Neutron Stars  

CERN Document Server

The X-ray spectra of some magnetized isolated neutron stars (NSs) show absorption features with equivalent widths (EWs) of 50 - 200 eV, whose nature is not yet well known. To explain the prominent absorption features in the soft X-ray spectra of the highly magnetized (B ~ 10^{14} G) X-ray dim isolated NSs (XDINSs), we theoretically investigate different NS local surface models, including naked condensed iron surfaces and partially ionized hydrogen model atmospheres, with semi-infinite and thin atmospheres above the condensed surface. We also developed a code for computing light curves and integral emergent spectra of magnetized neutron stars with various temperature and magnetic field distributions over the NS surface. We compare the general properties of the computed and observed light curves and integral spectra for XDINS RBS\\,1223 and conclude that the observations can be explained by a thin hydrogen atmosphere above the condensed iron ...

2010-01-01

472

AGN Outflows in Emission and Absorption: The SDSS Perspective  

CERN Document Server

A variety of investigations have demonstrated commonalities between the Baldwin (1977) Effect, the blueshifting of CIV emission lines (e.g., Gaskell 1982; Richards et al. 2002), and the L_UV-L_X relationship (e.g., Avni & Tananbaum 1982; Strateva et al. 2005; Steffen et al. 2006); indeed all three of these observational effects may be manifestations of the same underlying (but still uncertain) physics. This commonality is of interest to investigations of accretion disk winds (e.g., Murray et al. 1995; Proga et al. 2000) from active galactic nuclei (AGN) as there is evidence that broad absorption line quasars (BALQSOs) are drawn from a parent sample of quasars that exhibit larger than average CIV blueshifts, weaker than average CIV emission line strengths, and bluer than average (intrinsic) colors. The properties of the absorption troughs appear to be dependent upon these parameters. Thus, it is suggested that not all quasars will host ...

2006-01-01

473

Review of passive heat transfer augmentation techniques  

Energy Technology Data Exchange (ETDEWEB)

Heat transfer augmentation techniques (passive, active or a combination of passive and active methods) are commonly used in areas such as process industries, heating and cooling in evaporators, thermal power plants, air- conditioning equipment, refrigerators, radiators for space vehicles, automobiles, etc. Passive techniques, where inserts are used in the flow passage to augment the heat transfer rate, are advantageous compared with active techniques, because the insert manufacturing process is simple and these techniques can be easily employed in an existing heat exchanger. In design of compact heat exchangers, passive techniques of heat transfer augmentation can play an important role if a proper passive insert configuration can be selected according to the heat exchanger working condition (both flow and heat transfer ...

2004-12-01

474

Recovery of Water from Boiler Flue Gas  

Energy Technology Data Exchange (ETDEWEB)

This project dealt with use of condensing heat exchangers to recover water vapor from flue gas at coal-fired power plants. Pilot-scale heat transfer tests were performed to determine the relationship between flue gas moisture concentration, heat exchanger design and operating conditions, and water vapor condensation rate. The tests also determined the extent to which the condensation processes for water and acid vapors in flue gas can be made to occur separately in different heat transfer sections. The results showed flue gas water vapor condensed in the low temperature region of the heat exchanger system, with water capture efficiencies depending strongly on flue gas moisture content, cooling water inlet temperature, heat exchanger design and flue gas and cooling water flow rates. Sulfuric acid vapor condensed in both the high temperature and low temperature ...

2008-09-30

475

Mechanisms of heat transfer augmentatiton around the stagnation point of an impinging air jet laden with solid particles. Report 2. ; Effects of thermal properties of laden particles and heat transfer surface on heat transfer augmentation due to the unsteady heat conduction. Koki niso shototsu funryu no yodomiten kinbo ni okeru dennetsu sokushin kiko. 2. ; Sesshoku netsudendo ni yoru dennetsu sokushin ni taisuru ryushi to dennetsumen no netsubusseichi no eikyo to sono hyoka  

Energy Technology Data Exchange (ETDEWEB)

The heat transfer augmentation effect by the unsteady heat conduction between the particles and heat transfer surface is one of the main factors, causing the heat transfer augmentation around the stagnation point in the gas-solid two-phase impinging jet flow. By separating and evaluating that effect, material influence on it was studied of particles and heat transfer surface, together with change by the jet flow condition. That effect enlarged with enlarging in heat capacity, multiplied by the heat conduction coefficient, of both the particles and heat transfer surface, and if both of them were constant in material combination, was dominated by the contact frequency of particles per unit time. Therefore in case of lading solid particles, equal in weight, that effect enlarges with diminishing in particle diameter. Such a ...

1991-05-25

476

Fiscal 2000 project of inviting proposals for international joint research - invitation for international proposal (Energy conservation No.2). Achievement report on international joint study on popularization promotion of geothermal heat pump-assisted environmentally compatible heating system for Changchun City, China; 2000 nendo kokusai kyodo kenkyu teian kobo jigyo - kokusai teian kobo (Shoe No.2). Chinetsu heat pump ni yoru Chugoku Changchun shi kankyo tekigogata danbo system no fukyu sokushin ni kansuru kokusai kyodo kenkyu seika hokokusho  

Energy Technology Data Exchange (ETDEWEB)

A geothermal heat pump-assisted heating system is introduced into Changchun City and a survey is conducted to determine if the system may be popularized in this extremely cold region located in the northeastern part of China. In concrete terms, the hot water that circulates through the office building of Changchun Ground Heat Development Co., Ltd., is switched to hot water prepared by a geothermal heat pump. The test continued from December 2000 to March 2001. It is then concluded that heating by geothermal heat pumps will be fully serviceable to Changchun City. Implemented are (1) the shift from the coal fired boiler system to a geothermal heat pump system comprising 16 subterranean heat exchangers for the heating of the office building which is approximately 1000 m{sup 2} large, (2) long-term ...

2001-03-01

477

FY1998 research report on the basic research on geothermal district heating in Kamchatka, Russia; 1998 nendo Roshia Renpo Kamchatka shu ni okeru chinetsu riyo ni yoru chiiki danbo ni kansuru kiso chosa hokokusho  

Energy Technology Data Exchange (ETDEWEB)

Petropavlovsk-Kamchatky (P-K) city in Kamchatka, Russia is operating hot-water district heating using heavy oil boilers and waste hot water of thermal power plants as heat sources. Feasibility study was made on district heating using natural geothermal hot water and/or geothermal heat pump systems as heat sources of hot water supply for reduction of greenhouse effect gas emission. Among 3 areas including geothermal hot water, use of hot water in K area was impossible because of lower temperature and less spring water. Use of hot water in P and UP areas was impossible as primary hot water because of temperature drop to 64 degrees C during hot water supply toward P-K city. The building heating operation test was carried out using the geothermal heat pump system installed in a newly drilled heat exchange well of 100m deep. ...

1999-05-01

478

The ground state well depth position R {sub m} of Van der Waals molecules and the spectral line shapes  

Energy Technology Data Exchange (ETDEWEB)

As the ground state potential curve is strongly related to spectral line shapes, the minumum position of the ground state potential is obtained from the experiemental absorption profile k({delta}{nu}, T) at high density of the radiating atoms. The temperature dependence of the absorption processes of Hg and Cd lines 253.65 and 326.1 nm, respectively perturbed by inert gases (Xe, Kr, Ar and Ne) had been carefully studied over a wide spectral range. Using the point of the maximum temperature dependence {delta}{nu} {sub m} in each case, we are able to calculate the position of the ground state potential R {sub m} using a simple formula.

2006-09-15

479

The electron cyclotron absorption diagnostic for the JET pumped divertor plasma  

International Nuclear Information System (INIS)

We present the design of a diagnostic system to measure electron cyclotron absorption at the second harmonic E-mode resonance in the JET pumped divertor plasma. The diagnostic will measure transmission as a function of frequency along one or more sightlines from which the spatial profile of the n_eT_e product will be deduced. The divertor is briefly described, and the electron cyclotron resonance physics relevant to this measurement is reviewed. The problems of measuring transmission using an oversized transmission system are discussed and the chosen measurement technique, a swept frequency interferometer using a coherent radiation source, is described. A prototype of the instrument has been assembled to test the measurement technique. Some data demonstrating the instrument's characteristics are presented. The nonresonant losses, which may affect the interpretation of the measurement, are also discussed. (orig.).

1993-03-01

480

Terahertz time-domain spectroscopy of atmospheric water vapor from 0.4 to 2.7 THz.  

Energy Technology Data Exchange (ETDEWEB)

We conducted broadband absorption measurements of atmospheric water vapor in the ground state, X {sup 1}A{sub 1} (000), from 0.4 to 2.7 THz with a pressure broadening-limited resolution of 6.2 GHz using pulsed, terahertz time-domain spectroscopy (THz-TDS). We measured a total of seventy-two absorption lines and forty-nine lines were identified as H{sub 2}{sup 16}O resonances. All the H{sub 2}{sup 16}O lines identified were confirmed by comparing their center frequencies to experimental values available in the literature.

2005-10-01

481

Synthesis and characterization of myristic acid capped silver nanoparticles  

Energy Technology Data Exchange (ETDEWEB)

Reduction of silver myristate (AgMy) under mild thermal reaction conditions in a dipolar aprotic solvent i.e. N, N-dimethylformamide (DMF) has been carried out. UV-visible absorption measurements of dried and re-dispersible brown flocculants showed broad features of surface plasmon resonance (SPR) due to silver nanoparticles. The freshly isolated particles showed absorption bands at 414 and 485 nm, respectively, due to inter-particle coupling or clustering of silver ions and silver atoms. X-ray diffraction (XRD) pattern of fcc zero-valent silver resulted in crystallite size of about 10 nm. Scanning electron microscopy (SEM) revealed formation of rod shaped silver with increasing reaction temperature. Thermal analysis (TGA) showed about 10% weight loss due to organic capping.

2008-08-15

482

Study of some Ayurvedic Indian medicinal plants for the essential trace elemental contents by instrumental neutron activation analysis and atomic absorption spectroscopy techniques  

Energy Technology Data Exchange (ETDEWEB)

Elemental analysis of some medicinal plants used in the Indian Ayurvedic system was performed by employing instrumental neutron activation analysis (INAA) and atomic absorption spectroscopy (AAS) techniques. The samples were irradiated with thermal neutrons in a nuclear reactor and the induced activity was counted by gamma ray spectrometry using an efficiency calibrated high resolution high purity germanium (HPGe) detector. Most of the medicinal plants were found to be rich in one or more of the elements under study. The variation in elemental concentration in same medicinal plants samples collected in summer, winter and rainy seasons was studied and the biological effects of these elements on human beings are discussed. (orig.)

2009-07-01

483

Spectroscopic characteristics of erbium and ytterbium-activated laser media  

International Nuclear Information System (INIS)

Judd-Ofelt parameters (?2 = 5.09?10-20, ?4 0.92?10-20, and ?6 = 0.63?10-20 cm2) and oscillator strengths of fundamental optical transitions involved in lasing at wavelength 1.54 ?m have been calculated for borosilicophosphate glass co-activated with Er3+ and Tb3+ ions based on experimental luminescence and absorption spectra and refractive indices. The results were used to determine the emission (6?10-23 cm2) and absorption (5?10-21 cm2) cross sections for lambda = 1.54 ?m and the gain cross section as a function of inverse population levels. (authors)

2009-01-01

484

Range-resolved gas concentration measurements using tunable semiconductor lasers  

British Library Electronic Table of Contents (United Kingdom)

A method for range-resolved gas sensing using path-integrated optical systems is presented. The method involves dividing an absorption path into several measurement segments and extracting the gas concentration in each segment from two path-integrated measurements. We implemented the method with tunable lasers (a 1389-nm VCSEL and a 10.9-?m pulsed quantum cascade laser) and a group of retro reflectors (RRs) distributed along absorption paths. Using a rotating mirror with the VCSEL configuration, we could scan a group of seven tape RRs spaced by 10?cm in ??9?ms to extract an H2O concentration profile. Reduced H2O concentrations were recorded in the segments purged with dry air. Hollow corner cube RRs were used in the quantum cascade laser configuration at distances up to 1.1?km from the las...

2008-01-01

485

R and D on high efficiency CO{sub 2} separation processes for enhanced oil recovery at the University of Regina  

Energy Technology Data Exchange (ETDEWEB)

Research facilities and personnel in high efficiency separation processes for carbon dioxide removal from industrial sources, such as fossil fuel fired power stations, goal gasification plants, and hydrogen production units for enhanced oil recovery applications at the University of Regina were described. A brief summary of current projects, such as the determination of CO{sub 2} absorption capacity of sterically hindered amines, the formulation of high CO{sub 2} absorption capacity solvents, the search for high performance absorbers and regenerators, studies on material corrosion, and optimization and cost studies of co-production of CO{sub 2} and electricity, was also provided.

1997-02-01

486

Optical properties and up-conversion of Pr"3"+ doped CdS nanoparticles in sol-gel glasses  

International Nuclear Information System (INIS)

Silica glasses containing Pr"3"+ with and without CdS nanoparticles were prepared by sol-gel technique. The influence of CdS nanoparticles on Pr"3"+ doped glass was studied by absorption, photoluminescence and up-conversion. From the measured intensities of various absorption bands of these glasses, the Judd-Ofelt parameters ?_2, ?_4 and ?_6 have been evaluated. The radiative transition probability (A), radiative lifetime (?_R), branching ratio (?_R) and integrated emission cross-section (?_P) were calculated from excited states of "3P_1 and "3P_0 levels. The up-conversion emissions were found in the green, orange and red regions under 800 nm excitation with peaks 559, 612 and 688 nm respectively. On excitation with 370 nm also leads to similar green, orange and red regions.

2010-10-01

487

Mechanism of the accumulation effect in laser damage to polymers: appearance of microdamage due to an ionization absorption wave  

Energy Technology Data Exchange (ETDEWEB)

An investigation was made of the accumulation of laser damage to transparent polymers irradiated with nanosecond pulses from neodymium and ruby lasers. The damage was investigated by the method of scattering and luminescence in the visible and near ultraviolet parts of the spectrum. It was established that there were two stages in laser damage by repeated irradiation with pulses of intensity below the single-shot damage threshold. An absorbing defect evolved during the first stage in such a way as to create a thermal instability in the surrounding matrix. During the second stage this thermal instability caused spatial growth of laser damage because of propagation of an ionization-inducing absorption wave with a front traveling at the rate governed by the electron component of the thermal conductivity.

1984-04-01

488

Labelling of "1"4C-M-ISP and its absorption, translocation and distribution in peanut and soybean seedling  

International Nuclear Information System (INIS)

Labelling of "1"4C-M-ISP and its absorption, translocation and distribution in peanut and soybean seedling were studied. The results of experiments showed that the radioactive substance could be translocated in xylem and phloem of two kinds of plants. The root of peanut seedling absorbed "1"4C-M-ISP from the nutrient solution more strong than the root of soybean seedling did. After leaf treatment with "1"4C-M-ISP, the soybean seedling absorbed more radioactive substance than peanut seedling did. But the translocation's speed of radioactive substance in pnloem of two kinds of plants were similar.

1990-01-01

489

Kinetics of carbon dioxide absorption in aqueous solutions of diisopropanolamine  

Energy Technology Data Exchange (ETDEWEB)

A bubble column absorber was used to investigate kinetics of the reaction between carbon dioxide and aqueous solutions of diisopropanolamine (DIPA), by means of gas absorption experiments. These were conducted in the temperature range of 10 to 40deg C, with DIPA concentrations from 5 to 500 mol/m{sup 3}, and CO{sub 2} partial pressures between 5 and 101 kPa. A model based on the Danckwerts' surface reneval theory was used to analyze the experimental results and to determine the rate constant. The obtained data support the assumption of a second-order overall reaction, with the rate constants being well correlated by the Arrhenius equation: k{sub 2} = 1.112 x 10{sup 10} exp(-4848/T). (orig.).

1992-04-01

490

Irradiation of Langmuir-Blodgett multilayer preparations of phospholipids and a fatty acid. Pt. 1; Effect of UV radiation  

Energy Technology Data Exchange (ETDEWEB)

Langmuir-Blodgett (LB) preparations containing stacked monolayers of phospholipids or stearic acid were irradiated with UV light and the electric conductance perpendicular to the planes of the monolayers was measured. There was no observable change of conductance when LB preparations of stearic acid were irradiated. For LB preparations of phospholipids, a rise of conductance, dependent on dose rate, was observed, reaching an equilibrium level after a few hours. After irradiation the conductance fell with a temperature-dependent time constant, and eventually reached a final level a little above the initial value. A three-state model is proposed for the LB phospholipid preparations. This suggests that the absorption of one photon raises a molecule from the ground to an excited state; and the absorption of a second photon carries it into a damaged but repairable or metastable state. (author).

1992-12-01

491

Energy transfer study of europium-tetracycline complexes  

Energy Technology Data Exchange (ETDEWEB)

The aim of this work was to study the energy transfer mechanisms from the ligand to the central lanthanide ion of tetracycline-europium (Tc-Eu) complex. The absorption spectra of a EuCl{sub 3}.H{sub 2}O solution was measured and absorption cross-section of Eu{sup 3+} was estimated. The observed overlap predicts a resonant energy transfer from Tetracycline to Eu{sup 3+}. The microscopic parameter of energy transfer was obtained using the overlap integral calculation considering a dipole-dipole energy transfer mechanism and results were compared considering an energy transfer by exchange. In this work, we report also the optical properties of Tc-Eu complex when urea hydrogen peroxide is added to the aqueous solution.

2007-01-15

492

Determine equilibrium absorption rates  

Energy Technology Data Exchange (ETDEWEB)

Process engineers can predict quickly and accurately the equilibrium behavior of simultaneous H/sub 2/S and CO/sub 2/ absorptions in monoethanolamine and diethanolamine systems by using the nomographs developed by H.K. Ferguson Co. Correlation lines for temperature and amine concentration provided with the loading curves make the nomographs useful for any combination of temperature, concentration, and liquid loadings. The accuracy of the nomographs is within the acceptable range for normal engineering applications when the operating parameters lie in the region of practical gas-treating conditions. Correction curves given for each nomograph to improve the accuracy are generally not needed except for cases where the gas loadings are higher than 0.5 mole/mole of amine.

1980-04-01

493

Determination of some minor and trace elements in iron ores by ion exchange chromatography, spectrophotometry and atomic absorption spectrometry  

International Nuclear Information System (INIS)

A method is described for determination of aluminium, cadmium, cobalt, chromium, copper, calcium, magnesium, sodium, potassium, manganese, nickel, lead, strontium, zinc, titanium and vanadium in iron ore. After dissolution, a 1 gram sample of iron ore is applied to a column of AGI-X8 anion exchange resin (chloride form), in 100 ml of 7M HCl. Aluminium, chromium, calcium, magnesium, sodium, potassium, manganese, nickel, lead, strontium, titanium and vanadium are eluted with 7M HCl; iron, copper and cobalt are eluted with 0.5M HCl; cadmium and zinc are eluted with 2M HNO_3. Iron is subsequently removed from copper and cobalt by a solvent extraction with methyl isobutyl ketone. The elements are determined in the eluates by atomic absorption spectrometry, except for titanium and vanadium, which are determined spectrophotometrically.

494

Determination of Ca, Cr, Cu, Fe, K, Mg, Na and Zn in Brazilian medicinal plants by neutron activation and atomic absorption; Determinacao de Ca, Cr, Cu, Fe, K, Mg, Na e Zn em plantas medicinais brasileiras por ativacao neutronica e absorcao atomica  

Energy Technology Data Exchange (ETDEWEB)

Medicinal plants are available in the markets in Belo Horizonte, Minas Gerais. The objective of this work is to investigate the Ca, Cr, Cu, Fe, K, Mg, Na e Zn concentrations in two lots of usually known diuretics plants (azeitona do mato, cabelo de milho, cavalinha, cervejinha do campo, chapeu de couro, congonha de bugre, marmelinho do campo and quebra pedra) bought with an interval of time - six months - between the purchases. The elemental concentrations were determined applying k{sub 0} instrumental neutron activation analysis and atomic absorption spectrophotometry analysis. (author)

2002-07-01

495

Carbon dioxide absorption mechanisms of sodium added to calcium oxide at high temperatures  

Energy Technology Data Exchange (ETDEWEB)

To apply the CO{sub 2} absorber at about 1000{sup o}C for integrated coal gasification combined cycle (IGCC) furnace, the reactions of calcium oxide and CO{sub 2} at high temperatures was examined. Calcium carbonate reacts with sodium hydrogen carbonate below 200{sup o}C and forms sodium-calcium complex carbonate. The sodium-calcium complex carbonate melts at 813{sup o}C, and the carbon dioxide absorption and discharge reversible reactions of calcium-oxide takes place via liquid at around 1000{sup o}C. Sintering of calcium oxide at high temperature has been successfully avoided by the addition of sodium.

2004-07-01

496

Broad-linewidth laser absorption measurements of oxygen between 211 and 235nm at high temperatures  

British Library Electronic Table of Contents (United Kingdom)

Absorption coefficient data are presented for molecular oxygen at temperatures between 1100 and 2000K and discrete wavelengths between 211 and 235nm. Measurements were made behind reflected shock waves using broad-linewidth ultraviolet laser radiation generated from a frequency-quadrupled, tunable, pulsed Ti:Sapphire laser. Test mixtures consisting of 15% O"2, 15% He and balance Ar were used to minimize the influence of vibrational relaxation on the reflected shock temperature. The experimental results are in good agreement with theoretical calculations and confirm that discrete features from the Schumann-Runge system dominate between 211 and 235nm at temperatures higher than 1100K.

2011-01-01

497

Application of a new water-soluble polyethylenimine polymer sorbent for simultaneous separation and preconcentration of trace amounts of copper and manganese and their determination by atomic absorption spectrophotometry  

International Nuclear Information System (INIS)

In this work, a water-soluble polymer, polyethylenimine (PEI) was used for the simultaneous separation and preconcentration of trace Cu and Mn prior to their determination by flame atomic absorption spectrometry. For this purpose, the sample and the PEI solution were mixed and the metal-bound polymer was precipitated by adding acetone. The precipitate was separated and dissolved in a minimum amounts of water and aspirated into a flame AAS. By increasing the ratio of the volumes of sample to water used in dissolving the precipitate, the analyte elements were concentrated as needed. The sorption is quantitative in the pH ?6. Detection limits were 5.2 ?g/L for Cu and 5.4 ?g/L for Mn. This method is simple, fast and precise.

2006-04-21

498

Absorption of lead from the bronchial region of the lung  

International Nuclear Information System (INIS)

Experiments have been reported previously in which lead-212 ions with lead carrier were instilled into the lungs of anaesthetised rabbits. Experiments were also reported in which bismuth-207 chloride was instilled into rabbit lung. To check that the chloride compound was cleared in the same way as ions instilled in isolation, lead-203 chloride has been instilled in three rabbits. Measurements of absorption of ionic lead have been repeated using the radon-222 daughter, lead-214. Rates of clearance from the lung of "2"0"3Pb as the chloride and "2"1"2Pb ions are compared, and retention functions are derived. Clearance from the lung of "2"1"4Pb ions is also shown, and retention functions are derived. (U.K.).

1978-03-01

499

A liquid chromatography?fluorimetric method for the in vitro estimation of the skin penetration of disodium phenyldibenzimidazole tetrasulfonate from sunscreen formulations through human skin  

British Library Electronic Table of Contents (United Kingdom)

Disodium phenyldibenzimidazole tetrasulfonate (PDT) is a new organic UV filter with hydrophilic properties used in modern sunscreen spray formulations. The aim of this work was to develop and validate an analytical method that can be used to study skin absorption of PDT from sunscreens. Results obtained in vitro for human skin showed a low level of absorption. The proposed in vitro method employs a diffusion cell. Sunscreen lotion was applied onto pretreated human skin, which was then placed in the cell. PDT was collected in a receptor liquid, the surface of which was in contact with the skin. The solutions obtained were diluted appropriately and analyzed by liquid chromatography without any interference. The analytical features of chromatographic determination with fluorimetic detection w...

2006-01-01