WorldWideScience
1

Performance analysis on a hybrid air-conditioning system of a green building  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the performance analysis on a hybrid air-conditioning system according to the hybrid building energy system of the green building demonstration project in Shanghai, in which a 150 m{sup 2} solar collector is used to power two 10 kW adsorption chillers, a vapor compression heat pump is used to cool air in the evaporating end while the condensing heating at about 80{sup o}C is fully used to regenerate a liquid desiccant dehumidification system. In the hybrid system, the sensible cooling to the air is treated mainly by solar adsorption cooling and vapor compression cooling, whereas the latent heat is treated by the liquid desiccant dehumidification system with regeneration from the condensing heat of the heat pump. The results show that the performance of this system is 44.5% higher than conventional vapor compression system at a latent load of ...

2006-05-15

2

Visualization and measurement of refrigerant flow in compression-type refrigerator by neutron radiography  

International Nuclear Information System (INIS)

The refrigerant two-phase flows in a capillary tube and a distributor used in a compression-type refrigerator were visualized by real-time neutron radiography. The thermal neutron radiography system of JRR-3M at the Japan Atomic Energy Research Institute was used. In the visualization experiments of the two-phase flow in the capillary tube of 2 mm I.D., a cooled CCD camera was used, and the axial one-dimensional distributions of void fraction were measured. For the distributor, a high sensitivity video camera with a silicone intensified target tube was used. From the visualized images, the refrigerant behaviors in the distributor were clearly shown, and the liquid fraction in each tube was measured. As a result, it was shown that the refrigerant behaviors in the distributor effected the distributing performance of the refrigerant flow.

1999-11-03

3

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 studies, the flow channel ...

1993-08-01

4

Visualization and void fraction measurements of refrigerant flow in a refrigerator by neutron radiography  

Energy Technology Data Exchange (ETDEWEB)

The refrigerant two-phase flows in a distributor and a simulated plate heat exchanger with a single passage used in a compression-type refrigerator were visualized by real-time neutron radiography. For a distributor, the liquid fraction in the each tube was measured by some image processing method. On the other hand, for a plate heat exchanger, the two-dimensional distribution of void fraction was measured quantitatively by the umbra method. As a result, it was shown that the dynamic behaviors of refrigerant at the inlet of the section strongly affected on the performance, that is, a distribution performance of a distributor and a liquid distribution in a plate heat exchanger. (author)

2000-07-01

5

Desiccant cooling: parametric energy study  

Energy Technology Data Exchange (ETDEWEB)

Desiccants have been used in many applications to provide dehumidification. This paper describes an application of desiccants which provide both dehumidification and sensible cooling, with little or no use of conventional vapour-compression refrigeration plant. Through a parametric study, the energy consumption and costs of a desiccant cooling system are compared with those of a conventional vapour-compression refrigeration-based air-conditioning system. (author)

1998-12-31

6

Extension of the implicit curve-fitting method for fast calculation of thermodynamic properties of refrigerants in supercritical region  

Energy Technology Data Exchange (ETDEWEB)

The implicit curve-fitting method has been used for fast and stable calculations of thermodynamic properties of subcritical refrigerants, and it has to use the saturated liquid or vapor state as the reference state. In order to extend the application range of this method in supercritical region, an isothermal state in the supercritical region is used as the reference state, and the implicit equations for supercritical refrigerants in this state and out of this state are established, respectively. The new calculation method can be used in the entire supercritical region. With the new method, thermodynamic properties of supercritical CO{sub 2} and R410A are predicted and compared with REFPROP 8. It shows that the total mean relative deviations of the fast calculation formulae from REFPROP 8 are less than 1%, while the mean calculation speeds of the fast calculation formulae are more than 100 times faster than those of REFPROP ...

2009-11-15

7

Stored light and released fiction  

CERN Document Server

It is shown that the interpretation of the experimental results reported in the publication "Storage of Light in Atomic Vapor" by D.F.Phillips et al., Phys. Rev.Lett. 86, 783 (2001) [quant-ph/0012138] is incorrect. The experimental observation of this paper can be consistently explained in the framework of standard concepts of the physics of optical pumping and has nothing to do with "storage of light", or "dynamic reduction of the group velocity", or "light pulse compression".

2003-01-01

8

EFFECTIVE CONTROL OF SECONDARY WATER POLLUTION FROM FLUE GAS DESULFURIZATION SYSTEMS  

Science.gov (United States)

The report describes tests to demonstrate the feasibility of using a vertical-tube, falling-film, vapor-compression evaporator to concentrate waste water from a flue gas desulfurization (FGD) process. Tests showed that waste water from the Chiyoda FGD process can be concentrated ...

9

Development of High-Efficiency Low-Lift Vapor Compression System - Final Report  

Energy Technology Data Exchange (ETDEWEB)

PNNL, with cofunding from the Bonneville Power Administration (BPA) and Building Technologies Program, conducted a research and development activity targeted at addressing the energy efficiency goals targeted in the BPA roadmap. PNNL investigated an integrated heating, ventilation and air conditioning (HVAC) system option referred to as the low-lift cooling system that potentially offers an increase in HVAC energy performance relative to ASHRAE Standard 90.1-2004.

2010-03-31

10

ADVANCED UNDERGROUND GAS STORAGE CONCEPTS REFRIGERATED-MINED CAVERN STORAGE  

Energy Technology Data Exchange (ETDEWEB)

Limited demand and high cost has prevented the construction of hard rock caverns in this country for a number of years. The storage of natural gas in mined caverns may prove technically feasible if the geology of the targeted market area is suitable; and economically feasible if the cost and convenience of service is competitive with alternative available storage methods for peak supply requirements. It is believed that mined cavern storage can provide the advantages of high delivery rates and multiple fill-withdrawal cycles in areas where salt cavern storage is not possible. In this research project, PB-KBB merged advanced mining technologies and gas refrigeration techniques to develop conceptual designs and cost estimates to demonstrate the commercialization potential of the storage of refrigerated natural gas in hard rock caverns. Five regions of the U.S.A. were studied for underground storage development and PB-KBB reviewed the literature ...

1998-09-01

11

Technique for compressing light intensity ranges utilizing a specifically designed liquid crystal notch filter  

Energy Technology Data Exchange (ETDEWEB)

A pin hole camera assembly for use in viewing an object having a relatively large light intensity range, for example a crucible containing molten metal in an atomic vapor laser isotope separation (AVLIS) system is disclosed herein. The assembly includes means for optically compressing the light intensity range appearing at its input sufficient to make it receivable and decipherable by a standard video camera. To accomplish this, the assembly utilizes the combination of interference filter and a liquid crystal notch filter. The latter which preferably includes a cholesteric liquid crystal arrangement is configured to pass light at all wavelengths, except a relatively narrow wavelength band which defines the filter's notch, and includes means for causing the notch to vary to at least a limited extent with the intensity of light at its light incidence surface.

1988-01-01

12

Refrigerator operating experience on whole body MRI magnet systems  

International Nuclear Information System (INIS)

Several refrigerators for liquid helium and liquid nitrogen systems have been integrated successfully into IGC manufactured whole body Magnetic Resonance Imaging (MRI) magnet systems. The refrigerators have been tested in systems with magnetic fields of 0.6T to 1.5T. Tests were performed to study the effectiveness of the refrigerators, the magnetic field effects on the refrigerators, the effect of the refrigerators on the field uniformity and magnetic resonance image quality. The interface between the refrigerator and the whole body MRI magnet system cryostat was specifically designed to allow retrofit to the existing IGC magnet systems, while ensuring good heat transfer characteristics and good vibration isolation from the cryostat. The interface between the refrigerator and the cryostat and the refrigerator test ...

1985-08-01

13

Load calculation and system evaluation for electric vehicle climate control  

Energy Technology Data Exchange (ETDEWEB)

This paper presents an analysis of the applicability of alternative systems for electric vehicle (EV) heating and air conditioning (HVAC). The paper consists of two parts. The first part is a cooling and heating load calculation for electric vehicles. The second part is an evaluation of several systems that can provide the desired cooling and heating in EVs. These systems are ranked according to their overall weight The overall weight is calculated by adding the system weight and the weight of the battery necessary to provide energy for system operation. The system with the minimum overall weight is considered to be the best, because minimum vehicle weight decreases the energy required for propulsion, and therefore increases the vehicle range. Three systems are considered as the best choices for EV HVAC. These are, vapor compression, ice storage and adsorption systems. These systems are evaluated, including calculations of system weight, system ...

1994-09-12

14

Flow Vaporization of CO{sub 2} in Microchannel Tubes  

Energy Technology Data Exchange (ETDEWEB)

Carbon dioxide is receiving renewed interest as an efficient and environmentally safe refrigerant in a number of applications, including mobile air conditioning and heat pump systems, and hot water heat pumps. Compact heat exchangers for CO{sub 2} systems are designed with small-diameter tubing. The purpose of this study is therefore to provide a better basis for understanding and predicting heat transfer and pressure drop during flow vaporization of CO{sub 2} in microchannels. The ''unusual'' properties of carbon dioxide give heat transfer and two-phase flow characteristics that are very different from those of conventional refrigerants. Examples of these differences are the much higher pressure, the resulting high vapour density, a very low surface tension, and a low liquid viscosity. High pressure and low surface tension has a major effect on nucleate boiling characteristics, and ...

2002-07-01

15

final report on low-cycle fatigue and creep-fatigue testing of steam-filled alloy 800 specimens  

Energy Technology Data Exchange (ETDEWEB)

Uniaxial low-cycle fatigue and creep-fatigue tests have been carried out on hollow alloy 800 specimens that were filled with steam. Two testing temperatures were employed, each with its own steam condition. These temperatures and steam conditions were 650/sup 0/F with saturated steam (5% liquid, 95% vapor) and 1200/sup 0/F with superheated steam at 2200 psi. The low-cycle fatigue tests were carried out at both 650/sup 0/F and 1200/sup 0/F by cycling the strain between equal tensile and compressive magnitudes until specimen failure or until it was no longer practical to continue the test. The creep-fatigue tests were carried out to failure by cycling the strain in the same fashion as in the low-cycle fatigue tests but with holds imposed at either the peak tensile strain or the peak compressive strain or at both peak tensile and compressive strains in each loading cycle.

1981-02-01

16

Cardiac arrhythmia in refrigerator repairmen exposed to fluorocarbons.  

UK PubMed Central (United Kingdom)

A field study of 89 refrigerator repairmen was carried out to ascertain whether occupational exposure to fluorocarbons induces cardiac arrhythmia. The concentrations of fluorocarbons in the breathing...Full Text Available

1990-03-01

17

Utilization of cold in LNG baseload and peakshaving plants  

Science.gov (United States)

This report presents the results of a survey of the uses of the refrigeration available from vaporizing liquefied natural gas. The major emphasis of the study is on peakshaving plants, which liquefy and regasify domestic gas; the minor emphasis is on base-load terminals, which gasify imported LNG continuously. There are 54 full-scale LNG peakshaving plants in the US and several others under construction. The US has three operating base-load import terminals. One more is under construction and several more large terminals have been proposed. There are at least 12 foreign base-load import terminals in operation, and more are under construction or are proposed. The report presents a survey of operating conditions for about 15 large domestic peakshaving plants. It also presents published design data for the existing US import terminals, for the major proposed import terminals, and for the major overseas import terminals. The second section of the ...

1979-10-15

18

Prediction of critical properties of mixtures from the PRSV-2 equation of state: A correction for predicted critical volumes  

Energy Technology Data Exchange (ETDEWEB)

Critical properties of a fluid or fluid mixtures are important for describing fluid phase behavior, predicting physical properties, developing equations of state, and designing supercritical-fluid extraction processes, and compression and refrigeration units. The predictive capability of the Peng-Robinson-Styjek-Vera (PRSV-2) equation of state (1986) for critical properties of binary mixtures was investigated. The procedure adopted by Heidemann and Khalil (1980) and discussed by Abu-Eishah et al. (1998) was followed. An optimized value for the binary interaction parameter based on minimization of error between experimental and predicted critical temperatures was used. The standard and the average of the absolute relative deviations in critical properties are included. The predicted critical temperature and pressure for several nonpolar and polar systems agree well with experimental data and are always better than those predicted by the ...

1999-09-01

20

A progress for the health of south countries. The solar refrigerator; Un progres pour la sante dans les pays du Sud. Le refrigerateur solaire  

Energy Technology Data Exchange (ETDEWEB)

In order to conserve vaccines in hot countries a solar refrigerator has been made by a French university. It is a photothermal refrigerator without batteries. It uses two gases: ammonia and calcium chloride. The refrigerator is autonomous and can work eleven days without sun. (N.C.)

1998-05-01

21

PHYSICAL VAPOR DEPOSITION APPARATUS  

J-STORE (Japan)

Full Text Available

2007-09-14

22

Post-CHF Heat Transfer characteristics in one rod bundle geometry  

Energy Technology Data Exchange (ETDEWEB)

In the present paper, experimental study of forced convection boiling were performed to investigate the post-CHF characteristics of a vertical annular channel with one heated rod and four spacer grids for new refrigerant R-134a. The experiments were conducted under outlet pressure of 11.6, 13, 16 and 20 bar, mass fluxes of 100-600 kg/m{sup 2}s, and inlet temperatures of 25-51 .deg. C. The parametric trend of the post-CHF data was well consistent with previous studies. The two phase flow regime in tube flow occurring downstream of the CHF has been called post-CHF, dispersed flow, liquid-deficient flow, mist flow and film boiling. This regime is characterized by a continuous vapor phase with discrete liquid drops and a non-wetted heated surface. This regime has a considerable importance in the areas of light water reactor(LWR) accident analysis and other film boiling applications. The post-CHF region occurs by design in heat exchangers operating ...

2006-07-01

23

Post-CHF Heat Transfer characteristics in one rod bundle geometry  

International Nuclear Information System (INIS)

In the present paper, experimental study of forced convection boiling were performed to investigate the post-CHF characteristics of a vertical annular channel with one heated rod and four spacer grids for new refrigerant R-134a. The experiments were conducted under outlet pressure of 11.6, 13, 16 and 20 bar, mass fluxes of 100-600 kg/m2s, and inlet temperatures of 25-51 .deg. C. The parametric trend of the post-CHF data was well consistent with previous studies. The two phase flow regime in tube flow occurring downstream of the CHF has been called post-CHF, dispersed flow, liquid-deficient flow, mist flow and film boiling. This regime is characterized by a continuous vapor phase with discrete liquid drops and a non-wetted heated surface. This regime has a considerable importance in the areas of light water reactor(LWR) accident analysis and other film boiling applications. The post-CHF region occurs by design in heat exchangers operating in the ...

2006-11-02

24

Effect of safe environmental pre and post harvest treatments and irradiation on handling of some fruits  

International Nuclear Information System (INIS)

The present study was carried out during two successive seasons of 2005 and 2006 seasons on"Montakhab El-Kanater"guavas and"Hachiya"persimmons.two different experiments were studied, the first one for pre harvest and second post harvest. Regarding pre harvest experiment,hand or chemical flower thinning by urea or ethrel and date of fruit picking (maturity) were evaluated on both guavas and persimmons.All flower thinning treatments increased fruit set,total yield,average fruit weight and decreased fruit abscission.However,a great effect on fruit quality and chemical compositions were also found with flower thinning treatments. Chemical flower thinning was more effective than hand thinning in improving yield and quality in "Montakhab El-Kanater"guavas and "Hachiya"persimmons. However,early maturation(120 and 150 days for guava and persimmon respect.) produced poor fruit quality.Whereas, medium maturity(130 and 180 days for guava and persimmon respect.) produced fruit with high ...

25

Reduction of exhaust pollutants from a direct-injection diesel engine using oxygenated fuels. Fumigation of oxygenates and addition of oxygenated additives to fuel; Gansanso nenryo ni yoru chokusetsu funshashiki diesel kikan no haiki joka. Gansanso nenryo no kyukikan eno hojo funsha to keiyu eno tenka  

Energy Technology Data Exchange (ETDEWEB)

The effects on engine emissions resulting from the intake manifold fumigation of oxygenated fuel and the addition of oxygenates to the fuel have been investigated using a direct-injection diesel engine. The results show that carefully selected oxygenated fuels effectively work to increase the ignition delay because of their low ignition quality and to decrease the combustion temperature due to the low compression gas temperature produced from their large heat of vaporization, thereby reducing levels of Bosch smoke and nitrogen oxides simultaneously. However, supplementary injection of the oxygenates into the intake air causes a drastic increase in the levels of exhaust total hydrocarbons and CO; thus, it can be said that the addition of oxygenates to the fuel is more practical and effective than fumigation if phase separation of the blended fuel may not be occurred. In the case of addition of the oxygenates to the fuel, it is clarified that ...

1997-03-25

26

A study of flow boiling phenomena using real time neutron radiography  

International Nuclear Information System (INIS)

The operation and safety of both fossil-fuel and nuclear power stations depend on adequate cooling of the thermal source involved. This is usually accomplished using liquid coolants that are forced through the high temperature regions by a pumping system; this fluid then transports the thermal energy to another section of the power station. However, fluids that undergo boiling during this process create vapor that can be detrimental, and influence safe operation of other system components. The behavior of this vapor, or void, as it is generated and transported through the system is critical in predicting the operational and safety performance. This study uses two advanced penetrating radiation techniques, Real Time Neutron Radiography (RTNR), and High Speed X-Ray Tomography (HS-XCT), to examine void generation and transport behavior in a flow boiling system. The geometries studied were tube side flow boiling in a cylindrical configuration, and ...

1346-01-01

27

Onboard fuel reformers for fuel cell vehicles: Equilibrium, kinetic and system modeling  

Energy Technology Data Exchange (ETDEWEB)

On-board reforming of liquid fuels to hydrogen for use in proton exchange membrane (PEM) fuel cell electric vehicles (FCEVs) has been the subject of numerous investigations. In many respects, liquid fuels represent a more attractive method of carrying hydrogen than compressed hydrogen itself, promising greater vehicle range, shorter refilling times, increased safety, and perhaps most importantly, utilization of the current fuel distribution infrastructure. The drawbacks of on-board reformers include their inherent complexity [for example a POX reactor includes: a fuel vaporizer, a reformer, water-gas shift reactors, a preferential oxidation (PROX) unit for CO cleanup, heat exchangers for thermal integration, sensors and controls, etc.], weight, and expense relative to compressed H{sub 2}, as well as degraded fuel cell performance due to the presence of inert gases and impurities in the reformate. Partial oxidation (POX) of ...

1996-12-31

28

Looking back on 30 years of experience in the decontamination of radioactive, liquid effluents at KfK. The vapour compression evaporator, for example; 30 Jahre Abwasserdekontamination KfK, Erfahrung mit Bruedenkompressionsverdampfern  

Energy Technology Data Exchange (ETDEWEB)

The first equipment installed at KfK-HDB was a system with a thin-film evaporator. This was later replaced by two vapor compression evaporating units with forced circulation, for evaporation of liquid LAW, and a steam-heated natural circulation evaporator, for evaporation of liquid MAW. Nuclear activities of the Karlsruhe Nuclear Research Center phasing out, the liquid radwaste quantities to be treated have been shrinking accordingly, so that the current system is planned to be replaced by a smaller system with a thin-film evaporator. (orig./HP) [Deutsch] Im Laufe der Jahre wurde die Anlage mit Duennschichtverdampfer durch zwei Bruedenkompressionsverdampfer mit Zwangsumwaelzung fuer die Eindampfung leicht aktiver waessriger Abfaelle und einem dampfbeheizten Naturumlaufverdampfer fuer die Eindampfung mittelaktiver waessriger Abfaelle ersetzt. Mittlerweile sinkt der Abwasseranfall seit Jahren stetig aufgrund der sinkenden Aktivitaeten des ...

1994-05-01

29

Solar-powered refrigerator unit with solar module and transport equipment as stand-alone compact system. Solarkuehlgeraet mit Solarmodul und Transportvorrichtung als autonomes Kompaktsystem  

Energy Technology Data Exchange (ETDEWEB)

A compact and energy independent solar-powered refrigeration unit was to be developed to store and transport small quantities of high-quality commodities needing refrigeration. This unit comprises the following matched components: thermo-electrical refrigerator unit, solar generator and transport equipment. The solar generator is a specially developed panel with 36 cells. This unit may best be used in human medicine, veterinary medicine, environmental protection analysis, laboratories and leisure time activities. (BWI)

1994-01-01

30

A b s t r a c t Vo l u m e  

Wastenet

deodorants and sportswear and silver in washing ma- chines, refrigerators, health care products,

31

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

32

Study on compressed biogas and its application to the compression-ignition dual-fuel engine. Technical report  

Energy Technology Data Exchange (ETDEWEB)

This paper introduces in detail the compression performance of biogas, the application of compressed biogas to the compression-ignition engine and the possibility as well as the necessity of using compressed biogas. Moreover, the paper also goes further into some problems about the power increasing, efficiency raising and their social, economic and ecological beneficial results, when the compressed biogas is used in the compression ignition-dual fuel engine.

1987-01-01

33

MICROMECHANICS - COMPRESSIVE PROPERTIES OF ...  

Science.gov (United States)

... slenderness ratio. Equations which determine the ultimate compressive strength of a composite were established. Several ...

1965-05-01

34

Magnetic refrigeration: the promise and the problems  

Energy Technology Data Exchange (ETDEWEB)

Magnetic refrigeration uses the temperature- and field-dependence of the entropy of some magnetic materials to accomplish cooling. Because of the intrinsically high efficiency of the magnetization and demagnetization process and because of the potential for excellent heat transfer between solids and fluids, magnetic refrigerators promise to have higher efficiency than existing gas-cycle refrigerators. Many ground-based and space-based applications could benefit significantly from the cost savings implied by higher efficiency. Other attributes of these devices are high reliability and low volume and mass per unit cooling power. The development of these refrigerators is underway at several places around the world, including the Los Alamos National Laboratory. The progress to date has been encouraging but some problems have been clearly identified. The arguments for high efficiency and the problems that ...

1984-01-01

35

Excitonic transitions in InGaP/InAlGaP strained quantum wells  

International Nuclear Information System (INIS)

Excitonic transitions in metalorganic vapor phase epitaxially grown In_xGa_1_-_xP/In_0_._4_8(Al_0_._7Ga_0_._3)_0_._5_2P strained single quantum-well structures are characterized using low-temperature photoluminescence and photoluminescence excitation (PLE) spectroscopies. The structures consist of several uncoupled quantum wells with thicknesses between 1.2 and 11.3 nm, and compositions x of 0.48 (nominally lattice matched) and 0.56 (#approx#0.6% biaxial compressive strain). The photoluminescence spectra exhibit intense peaks over the wavelength range 550--650 nm, with linewidths between 7 and 23 meV depending on the well thickness. The PLE spectra reveal strong heavy-hole and light-hole transitions, as well as higher-order (n=2) transitions in the thicker wells. The heavy-hole/light-hole splitting shows little dependence on well thickness in the strained structures, indicating a relatively large conduction band offset of ...

36

AlGaInP single quantum well laser diodes  

Energy Technology Data Exchange (ETDEWEB)

The properties and low pressure organometallic vapor phase epitaxy of Ga{sub x}In{sub 1{minus}x}P/(AlGa){sub 0.5}In{sub 0.5}P quantum well (QW) laser diode heterostructures with Al{sub 0.5}In{sub 0.5}P cladding layers, and having wavelength 614 < {lambda} < 690 nm, are described. At longer wavelengths ({lambda} > 660 nm), threshold current densities under 200 A/cm{sup 2} and efficiencies greater than 75% result from a biaxially-compressed GaInP QW active region. Although short wavelength laser performance is diminished by the poor electron confinement afforded by AlGaInP heterostructures, good 630 nm band performance, and extension into the 610 nm band, is achieved with strained, single QW active regions.

1994-12-31

37

Study of the thermal plasma etching at atmospheric pressure on silica rods  

International Nuclear Information System (INIS)

Etching of SiO_2 rods has been obtained with a dc torch with argon as the process gas in an air environment at atmospheric pressure; the high temperature of the plasma jet causes vaporization of the exposed area. The apparatus and torch operative parameters have been set up to obtain a depth etch rate of up to 0.6 mm min"-"1 corresponding to 0.826 g min"-"1. An enthalpy probe has been employed to monitor the plasma conditions before the thermal plasma etching process and from the experimental etch rate a surface rod temperature of T_s_u_r = 2057 K has been derived. Etching has been obtained with uniformity over the entire exposed area with peak to peak differences below 1%. The plasma to rod heat transfer has been simulated using a commercial CFD code Fluent (copyright). The model consists of a non-steady two-dimensional simulation for a compressible turbulent fluid, with an adapted grid calculation. Boundary conditions have been set out using ...

2004-04-21

38

Measurements of water vapor adsorption on the Geysers rocks  

Energy Technology Data Exchange (ETDEWEB)

The ORNL high temperature isopiestic apparatus was adapted for adsorption measurements. The quantity of water retained by rock samples taken from three different wells of The Geysers was measured at 150 °C and at 200 °C as a function of pressure in the range 0.00 ≤ p/p0 ≤ 0.98, where p0 is the saturated water vapor pressure. The rocks were crushed and sieved into three fractions of different grain sizes (with different specific surface areas). Both adsorption (increasing pressure) and desorption (decreasing pressure) runs were made in order to investigate the nature and extent of the hysteresis. Additionally, BET surface area analyses were performed by Porous Materials Inc. on the same rock samples using nitrogen or krypton adsorption measurements at 77 K. Specific surface areas and pore volumes were determined. These parameters are important in estimating water retention capability of a ...

1996-01-24

41

Application of neutron radiography to a diagnosis of refrigerator  

International Nuclear Information System (INIS)

A diagnosis of the refrigerant flows in a refrigerator was carried out by real-time neutron radiography. The thermal neutron radiography system of JRR-3M in Japan Atomic Energy Research Institute and the real-time image processing system developed by Musashi Institute of Technology were used. Freon evaporating flows in the evaporator, condensing flows in the condenser, flashing flows in the capillary tube and flows in the accumulator were visualized and the dynamic behaviors under practical conditions were clarified. In the case of the capillary tube of 0.8 mm i.d., a cooled-CCD camera was utilized. (orig.).

1996-07-01

42

The Effect of Compressive Loading on the Fatigue Lifetime of ...  

Science.gov (United States)

... Coupon 119 * 52 Probability of Survival Versus Ultimate Compressive Strength for Un-notched Laminate 1 Coupon ipn ...

1979-10-01

43

Compressive and Shear Buckling Analysis of Metal Matrix ...  

Science.gov (United States)

... Title : Compressive and Shear Buckling Analysis of Metal Matrix Composite Sandwich Panels Under Different Thermal Environments. ...

44

On-line nuclear orientation  

Energy Technology Data Exchange (ETDEWEB)

This report discusses: shape coexistence in {sup 184}Pt; nuclear structure of {sup 187}Ir; g-factors of excited states; OLNO-2; and refrigerator development.

1992-01-01

45

On-line nuclear orientation  

International Nuclear Information System (INIS)

This report discusses: shape coexistence in "1"8"4Pt; nuclear structure of "1"8"7Ir; g-factors of excited states; OLNO-2; and refrigerator development.

46

Design and optimization of thermoacoustic devices  

International Nuclear Information System (INIS)

Thermoacoustics deals with the conversion of heat energy into sound energy and vice versa. It is a new and emerging technology which has a strong potential towards the development of sustainable and renewable energy systems by utilizing waste heat or solar energy. Although simple to fabricate, the designing of thermoacoustic devices is very challenging. In the present study, a comprehensive design and optimization algorithm is developed for designing thermoacoustic devices. The unique feature of the present algorithm is its ability to design thermoacoustically-driven thermoacoustic refrigerators that can serve as sustainable refrigeration systems. In addition, new features based on the energy balance are also included to design individual thermoacoustic engines and acoustically-driven thermoacoustic refrigerators. As a case study, a thermoacoustically-driven thermoacoustic refrigerator has been designed ...

2008-12-01

47

Investigation and improvement of ejector refrigeration system using computational fluid dynamics technique  

Energy Technology Data Exchange (ETDEWEB)

Ejector refrigeration systems are usually designed to utilize low grade energy for driving the cycle. They also have low maintenance cost because they operate without a compressor. Mainly, the ejector performance directly affects the refrigerating performance. Therefore, an investigation on the characteristics and an efficient design of the ejector are important to improve ejector refrigeration systems. In this study, the computational fluid dynamics (CFD) code, FLUENT, is employed to predict the flow phenomena and performance of CPM and CMA steam ejectors. The ejector refrigeration system, using water as the working fluid, is operated at 120-140 C boiler temperature and 5-15 C evaporator temperature. CFD can predict ejector performance very well and reveal the effect of operating conditions on an effective area that is directly related to its performance. Besides, it is found that the flow pattern does ...

2007-09-15

48

An implicit curve-fitting method for fast calculation of thermal properties of pure and mixed refrigerants  

Energy Technology Data Exchange (ETDEWEB)

Calculations of refrigerant thermal properties are desired to be very fast and stable in cases of simulation of refrigeration system, etc. The traditional method based on equation of state cannot meet such requirement because of unavoidable iterations in calculation. In this paper, a new calculation method for refrigerant thermal properties is presented. Low order implicit polynomial equations are got by using curve-fitting method at first, and then explicit formulae for calculating refrigerant thermal properties quickly are obtained by getting the analytical solution of these implicit equations. Explicit fast calculation formulae for thermal properties of R22 and R407C, covering the saturated temperature of -60{approx}80 {sup o}C and superheat of 0-65 {sup o}C, are presented as examples. The calculation speeds of the formulae of R22 are about 140 times faster than those of REFPROP 6.01 while the ...

2005-09-01

49

EHD enhancement of pool and in-tube boiling of alternate refrigerants. Final report, 15 January 1993--15 June 1993  

Energy Technology Data Exchange (ETDEWEB)

The Electrohydrodynamic (EHD) is an active heat transfer augmentation technique which utilizes the effect of secondary motions generated through the application of an electrostatic potential to a dielectric fluid. Net result is better momentum and heat transfer between the fluid and the heat transfer wall through destabilization of the thermal boundary layer and better mixing of the fluid adjacent to the heat transfer surface. EHD enhancement of refrigerant/refrigerant oil mixtures heat transfer using the Electrohydrodynamic (EHD) technique is the subject of a three-year experimental investigation in a project funded by the US Department of Energy, effective June 1, 1993. For the interim period between November 1992 and June 1993 when the DOE funds became available, the Air-Conditioning and Refrigeration Technology Institute (ARTI) provided partial funding for our EHD research program with the aim of accomplishing three major tasks: (1) conduct ...

1993-08-01

53

Microbuckling compression failure of a radiation-induced wood/polymer composite  

Energy Technology Data Exchange (ETDEWEB)

A wood/polymer composite was produced by impregnating Ramin wood with methyl methacrylate monomer and subsequently polymerizing it by gamma irradiation. To assess the improvement in compression strength of the wood caused by the polymer impregnation, a microbuckling compression failure mechanism was used to model the compression failure of the composite. Such a mechanism was found to predict a linear relationship between the compression strength and the percentage polymer impregnation (by weight). Uniaxial compression test results at 45({plus minus}5)% and 90({plus minus}5)% relative humidity levels, after being statistically analysed, showed that such a linear relationship was valid for up to 100% polymer impregnation. (author).

1990-01-01

54

Microbuckling compression failure of a radiation-induced wood/polymer composite  

International Nuclear Information System (INIS)

A wood/polymer composite was produced by impregnating Ramin wood with methyl methacrylate monomer and subsequently polymerizing it by gamma irradiation. To assess the improvement in compression strength of the wood caused by the polymer impregnation, a microbuckling compression failure mechanism was used to model the compression failure of the composite. Such a mechanism was found to predict a linear relationship between the compression strength and the percentage polymer impregnation (by weight). Uniaxial compression test results at 45(#+-#5)% and 90(#+-#5)% relative humidity levels, after being statistically analysed, showed that such a linear relationship was valid for up to 100% polymer impregnation. (author).

1990-01-01

55

Engineering Relative Compression of Genomes  

CERN Document Server

Technology progress in DNA sequencing boosts the genomic database growth at faster and faster rate. Compression, accompanied with random access capabilities, is the key to maintain those huge amounts of data. In this paper we present an LZ77-style compression scheme for relative compression of multiple genomes of the same species. While the solution bears similarity to known algorithms, it offers significantly higher compression ratios at compression speed over a order of magnitude greater. One of the new successful ideas is augmenting the reference sequence with phrases from the other sequences, making more LZ-matches available.

2011-01-01

56

A study on compressed biogas and its application to the compression ignition dual-fuel engine  

Energy Technology Data Exchange (ETDEWEB)

This paper is based on research on the combustion ignition dual-fuel engine conducted at the Zhejiang Agricultural University. The properties of compressed biogas, its performance characteristics in the compression ignited dual-fuel engine as well as the possibilities and needs for its use are discussed. Using information derived from experimental data compiled by the laboratory, analyses and comparisons have been made between high- and low-pressure biogas used in the compression ignition dual-fuel engine with respect to variation of power and the corresponding characteristic curve of the engine. The economic effects of utilizing compressed biogas are also discussed. (author).

1989-01-01

57

Solar-powered cooling systems: Technical and economic analysis on industrial refrigeration and air-conditioning applications  

British Library Electronic Table of Contents (United Kingdom)

In the last years, the growing demand for air conditioning has caused a significant increase in demand for primary energy resources. Solar-powered cooling is one of the technologies which allows to obtain, by using the renewable solar source, an important energy saving compared to traditional air conditioning plants. The paper describes different technical installations for solar cooling, their way of operation, advantages and limits. The objective of the present study has been to analyze the technical and economic feasibility of solar absorption cooling systems, designed for two different application fields: industrial refrigeration and air conditioning. The possibility to replace or integrate the existing plants is studied, by considering the refrigeration requirements of a company, whic...

2009-01-01

58

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

59

Ultimate Compressive Strength and Nonlinear Stress-Strain ...  

Science.gov (United States)

... Accession Number : ADD421949. Title : Ultimate Compressive Strength and Nonlinear Stress-Strain Curves of Graphite/Epoxy Laminates,. ...

1976-10-12

60

RESEARCH AND DEVELOPMENT OF AN ADVANCED ...  

Science.gov (United States)

... 28 Thickness vs Ultimate Compressive Strength for LM-833 Magnesia. ... Ultimate Tensile Stress (S) = 0. 112 * 0. 012 Ultimate Compressive Strength ...

1963-05-01

61

NASA Tectnnicll Memorandum 8760c - NASA Technical Reports ...  

Science.gov (United States)

Ultimate compressive strength and failure modes were studied using 24- ... to 81 % of the average ultimate compressive strength (UCS). Figure 1 (a) is the failure ...

62

Measured and Predicted Structural Behavior of the HiMAT Tailored ...  

Science.gov (United States)

Ultimate compressive strength in the longitudinal direction. (3. Ultimate tensile strength in the transverse direction. U'. Ultimate compressive strength in ...

63

Development of Material Properties for Slurry Infiltrated Fiber ...  

Science.gov (United States)

... Page 26 Ultimate compressive strength versus fly ash/cement limits 41 ... 222 El Ultimate compressive strength versus water/(cement + fly ash) 250 ...

1988-09-01

64

Control of Flow Separation Using Adaptive Airfoils  

Science.gov (United States)

... been demonstrated in steady compressible flows. ... steady Compressible Flow on an Oscillating Airfoil ... of Oscillating Airfoils", AGARD-CP-552, Aug. ...

1997-01-01

65

Compression Testing of Continuous P-100 Fiber Reinforced ...  

Science.gov (United States)

... The measured elastic modulus was fairly close to the predicted value, but the ultimate compressive strength (UCS) was quite a bit below the MSC ...

1991-10-01

66

COMPRESSIVE STRENGTH OF CONOLON 506 AT +75F ...  

Science.gov (United States)

... Abstract : The ultimate compressive strength of Conolon 506 increases from 39,200 psi at +78F to 57,100 psi at -320F. ...

1962-01-11

68

Study of the effect of noncondensable gas on heat transfer phenomena in horizontal steam generator of pactel facility with CATHARE2 V1.5a  

International Nuclear Information System (INIS)

Lappeenranta University of Technology (LTKK) and VTT Energy carried out a series of preliminary tests in 1999 to study the behavior of noncondensable (NC) gases in VVER geometry. The tests aimed at studying the effect of NC gases on system thermal-hydraulics and on heat transfer in a horizontal steam generator (HSG). The system behavior can be affected by hydrogen produced in the core in case of a severe accident, by nitrogen from hydro-accumulators released into the primary circuit in case of a loss-of-coolant accident (LOCA) and more generally by any NC gas in all cases where cooling is ensured by natural circulation. A secondary objective of the tests - the first series of tests ever performed with NC gas with PACTEL - was to find out, if the instrumentation of PACTEL was adequate for this type of tests and if it was functioning properly. This paper presents the measured and calculated (CATHARE code version V15a mod 2.1) results of the test NCg-l. It was carried out in natural ...

2001-03-20

69

Molybdenum. Suppl. Vol. A 2a. Element. Physical properties. Pt. 1. 8. Rev. Ed  

Energy Technology Data Exchange (ETDEWEB)

The major part of the chapter 'Physical Properties' in concerned with, in addition to nuclear and atomic properties, the properties of the metal molybdenum. Due to the huge number of relevant papers, the present volume comprises only the first part of the metal properties, i.e. the crystallographic properties, the electronic structure, the lattice dynamics, and subsequently the mechanical and thermal properties. There are two small sections where the properties of the molecules, primarily Mo/sub 2/ and Mo/sub 6/, and of the vapor are described. The strength and some other mechanical properties have been frequently investigated to establish the change due to neutron irradiation, because this affects the durability of the fuel containers in nuclear reactors. For that purpose, changes in structure, texture, etc., due to irradiation had to be determined; the structural properties of nonirradiated samples also had to be studied in great detail, the ...

1985-01-01

70

The future of refrigeration and air conditioning. The master shows in restriction. Expert discussion on the work of the UNEP Technology and Economics Assessment Panel. Zur Zukunft der Kaelte und Klimatechnik. In der Beschraenkung zeigt sich der Meister. Ein Fachgespraech zur Arbeit des UNEP Technology and Economics Assessment Panels  

Energy Technology Data Exchange (ETDEWEB)

On behalf of the United Nations Environment Programme (UNEP) a study has been established by the Refrigeration, Air Conditioning and Heat Pump Technical Options Committee in which famous experts of refrigeration technology compiled facts which allow for a reliable prospect of real possibilities of changing from fluorine hydrogen to ozone innoxious substitutes and substitute technologies. With regard to the organization, a division into 6 committees for the establishment of the study has been made: 1. Refrigeration Options Committee, 2. Foams Options Committee, 3. Solvents, Coatings and Adhesives Options Committee, 4. Aerosols, Sterilants and Miscellaneous Uses Options Committee, 5. Halons Technical Options Committee and 6. Economic Options Committee. (BWI).

1992-09-01

71

On-line nuclear orientation. Progress report, April 1, 1991--March 31, 1992  

Energy Technology Data Exchange (ETDEWEB)

This report discusses: shape coexistence in {sup 184}Pt; nuclear structure of {sup 187}Ir; g-factors of excited states; OLNO-2; and refrigerator development.

1992-06-01

72

Mutagenicity of stemphyltoxin III, a metabolite of Alternaria alternata.  

UK PubMed Central (United Kingdom)

Some common decay organisms of vegetables and ripened fruits are Alternaria species. Even fruits and vegetables kept under refrigeration can be spoiled by Alternaria species because the mold grows at...Full Text Available

1991-01-01

73

Global residential appliance standards  

Energy Technology Data Exchange (ETDEWEB)

In most countries, residential electricity consumption typically ranges from 20% to 40% of total electricity consumption. This energy is used for heating, cooling, refrigeration and other end-uses. Significant energy savings are possible if new appliance purchases are for models with higher efficiency than that of existing models. There are several ways to ensure or encourage such an outcome, for example, appliance rebates, innovative procurement, and minimum efficiency standards. This paper focuses on the latter approach. At the present time, the US is the only country with comprehensive appliance energy efficiency standards. However, many other countries, such as Australia, Canada, the European Community (EC), Japan and Korea, are considering enacting standards. The greatest potential impact of minimum efficiency standards for appliances is in the developing countries (e.g., China and India), where saturations of household appliances are relatively low but ...

1993-03-01

74

Evaluation of energy-conservation technologies for the citrus-processing industry  

Energy Technology Data Exchange (ETDEWEB)

The following manual chapters are outlined and described: overview, boilers, juice evaporators, feed mills, refrigeration, additional energy savings potentials, emerging technologies, optimization of integrated plant energy systems, and economics. (MHR)

1980-01-01

75

Active magnetic regenerator  

Energy Technology Data Exchange (ETDEWEB)

The disclosure is directed to an active magnetic regenerator apparatus and method. Brayton, Stirling, Ericsson, and Carnot cycles and the like may be utilized in an active magnetic regenerator to provide efficient refrigeration over relatively large temperature ranges.

1982-01-01

76

The state of the art: Appliances  

Energy Technology Data Exchange (ETDEWEB)

This original volume of the Appliances Atlas includes discussion of residential appliances, commercial refrigeration and cooking, and office equipment. (The residential appliances section has since been updated in the E Source 1994 Residential Appliances Technology Atlas.) The commercial refrigeration section contains details on efficiency opportunities through load reduction and mechanical system improvements, while commercial cooking covers improvements to electric and gas fryers, griddles, ovens, cooktops, broilers, and steam equipment. The office equipment section offers discussion of trends and energy use of computers and their components, imaging technologies, and communication equipment. (Published under the former name, Competitek.)

1990-12-31

77

Presentations from 2nd Cryogenic Operations Workshop (CRYO 2006) , May 9-11, 2006, Menlo Park, California  

Science.gov (United States)

This workshop covered the latest practical engineering and operational management applications and techniques that have been found to enhance operational costs, reliability, and flexibility, with topics such as establishing the optimal refrigeration design cycle and operating design points; utility management; manpower scheduling; plant control philosophy and automation; short and long term maintenance scheduling; refrigerant loss detection and control; system contamination; component reliability; and equipment technical performance issues.

2006-11-10

78

Gamma irradiation in the control of pathogenic bacteria in refrigerated ground chicken meat; Irradiacao gama no controle de bacterias patogenicas em carne de frango refrigerada  

Energy Technology Data Exchange (ETDEWEB)

This work evaluated the effect of gamma radiation on reducing the population of Staphylococcus aureus, Escherichia coli nd Salmonella typhimurium in ground chicken breast stored under refrigeration. The experiment included a control and 4 doses of gamma radiation ( 2.0, 4.0, 6.0 and 8.0 kGy) along with 5 periods of storage under refrigeration ( 1, 7 14, 21 and 28 days). Samples of ground chicken breast were inoculated with Staphylococcus aureus (ATCC 14458), Escherichia coli (ATCC 11105) and Salmonella typhimurium (ATCC 0626), irradiated at temperatures between 4 and 8 deg C and stored under refrigeration (5 deg C) for 28 days. The increased radiation dose and period of storage under refrigeration caused a reduction of Staphylococcus aureus, Escherichia coli and Salmonella typhimurium populations in the ground chicken breast. Mean radiation D values determined for Staphylococcus aureus and Escherichia ...

2000-09-01

79

THE EFFECTS OF ONE MEGACYCLE ULTRASONIC ...  

Science.gov (United States)

... ULTRASONIC VIBRATION TO PORTLAND CEMENT-WATER PASTE REDUCES THE ULTIMATE COMPRESSIVE STRENGTH OF MORTARS ...

1959-09-09

80

THE EFFECT OF FIBRE MISALIGNMENT ON THE ...  

Science.gov (United States)

... and testing of unidirectional composites, there are serious doubts about the possibility of obtaining a true ultimate compressive strength for this kind ...

86

Argon Arc Welding for Pipelines  

International Science & Technology Center (ISTC)

Improvement of Methods of Automatic Self-Compression Argon Arc Welding for Pipelines

87

'__-_ _! _/_/ _  

Science.gov (United States)

In 1963, Grover and co-workers at the Los Alamos. Scientific. Laboratory ...... and A. P. Watkins. (1986) "The Computation of Compressible ...

88

Spacer grid effects on post-CHF heat transfer in an annulus geometry  

Energy Technology Data Exchange (ETDEWEB)

The term 'Post-CHF' was generally used in the two-phase flow regime in tube flow occurring downstream of the CHF. It has various other names such as dispersed flow, liquid-deficient flow, mist flow and film boiling because the two-phase regime is characterized by a continuous vapor phase with discrete liquid drops and a non-wetted heated surface. The regime has been adopted in a lot of applications including nuclear power plants, fossil power plants, steam generators, refrigeration systems and spray cooling, In particular, this regime has a considerable importance in the areas of light water reactor(LWR) accident analysis (off-normal operating conditions) and design in heat exchangers operating in the once-through mode where subcooled liquid enters the exchanger and superheated vapor exits. Recently, innovative PWRs adopt very high power density increases and so require increased safety margins. For ...

2005-07-01

89

Spacer grid effects on post-CHF heat transfer in an annulus geometry  

International Nuclear Information System (INIS)

The term 'Post-CHF' was generally used in the two-phase flow regime in tube flow occurring downstream of the CHF. It has various other names such as dispersed flow, liquid-deficient flow, mist flow and film boiling because the two-phase regime is characterized by a continuous vapor phase with discrete liquid drops and a non-wetted heated surface. The regime has been adopted in a lot of applications including nuclear power plants, fossil power plants, steam generators, refrigeration systems and spray cooling, In particular, this regime has a considerable importance in the areas of light water reactor(LWR) accident analysis (off-normal operating conditions) and design in heat exchangers operating in the once-through mode where subcooled liquid enters the exchanger and superheated vapor exits. Recently, innovative PWRs adopt very high power density increases and so require increased safety margins. For instance, advanced PWRs ...

2005-05-26

90

On Sensitivity of Spectral Radiative Fluxes to Atmospheric Water Vapor in the 940 nm Region (Numerical Simulation)  

Energy Technology Data Exchange (ETDEWEB)

Water vapor is well known to be a critical component in many aspects of atmospheric research, such as radiative transfer and cloud and aerosol processes. This requires both improved measurements of the columnar water vapor and its profiles in the atmosphere in a wide range of conditions, and adjustment of water vapor parameterizations in radiation codes including the perfection of spectroscopic parameters. In this paper we will present the results of comparison of our calculations and downward solar fluxes measured with Rotating Shadowband Spectroradiometer under conditions of horizontally homogeneous clouds. We also will discuss the sensitivity of atmospheric radiation characteristics to variations of water vapor in the band 940 nm: these results may be useful for development of new methods of retrieval of the total column water vapor content (WVC) in the atmosphere from data of ...

2005-03-18

91

Study on the separation characteristics of tritiated water vapor adsorption.  

Science.gov (United States)

In order to reduce the air concentration of (sup 3)H in the reactor buiIding of Wolsung Heavy Water Reactor, a computer code for estimation of adsorption behavior was programmed based on an equation derived for analysis of water vapor adsorption, and a ba...

1991-01-01

92

Meteorologial Techniques  

Science.gov (United States)

... 2-93 An Atmospheric Particle Emits Electromagnetic ... atmospheric water vapor produces a hydrometeor. ... subject to wind movement (either blowing ...

2003-06-13

93

Stanford geothermal program. Final report, July 1990--June 1996  

Science.gov (United States)

This report discusses the following: (1) improving models of vapor-dominated geothermal fields: the effects of adsorption; (2) adsorption characteristics of rocks from vapor-dominated geothermal reservoir at the Geysers, CA; (3) optimizing reinjection strategy at Palinpinon, Philippines based on chloride data; (4) optimization of water injection into vapor-dominated geothermal reservoirs; and (5) steam-water relative permeability.

1998-03-01

94

Explosives detection: the problem and prospects  

Energy Technology Data Exchange (ETDEWEB)

The history of explosives vapor detection includes almost every detection strategy known to man. Initial attempts to utilize these techniques were dismal failures. However, with the development of the Electron Capture Detector (ECD), the first promising detection of explosives vapors became possible. The present commercial explosives detectors detect the higher vapor pressure materials but not the whole spectrum. This paper describes the basic properties of explosives molecules and our research to utilize these properties for increased detection sensitivity.

1984-01-01

95

Daytime Raman lidar measurements of water vapor during the ARM 1997 water vapor intensive observation period  

Energy Technology Data Exchange (ETDEWEB)

Because of the importance of water vapor, the ARM program initiated a series of three intensive operating periods (IOPs) at its CART (Cloud And Radiation Testbed) site. The goal of these IOPs is to improve and validate the state-of-the-art capabilities in measuring water vapor. To date, two of the planned three IOPs have occurred: the first was in September of 1996, with an emphasis on the lowest kilometer, while the second was conducted from September--October 1997 with a focus on both the upper troposphere and lowest kilometer. These IOPs provided an excellent opportunity to compare measurements from other systems with those made by the CART Raman lidar. This paper addresses primarily the daytime water vapor measurements made by the lidar system during the second of these IOPs.

1998-04-01

96

Refrigeration loads in a freezer due to hot gas defrost and their associated costs  

Energy Technology Data Exchange (ETDEWEB)

The build-up of frost on unit cooler surfaces, if not periodically cleared, will eventually cause impairment of the unit's performance, eventually rendering it useless. Thus it is necessary, in spaces below freezing, to provide an external supply of heat to warm the unit sufficiently to melt the frost and remove it. In large central-plant-type systems the most common method employed for supplying heat is from the high-pressure side of the refrigeration system, referred to as hot gas defrost. Although the heat thus captured for use in melting frost would otherwise be rejected external to the system, the defrosting process is not free of cost. There are significant losses associated with the process the magnitude of which have not heretofore been fully identified. This paper looks at the heat and mass transfer and fluid flow mechanisms involved in the hot gas defrost process in large commercial freezers. It suggests some mathematical models for analysis of ...

1989-01-01

97

Prediction of refrigerant void fraction in horizontal tubes using probabilistic flow regime maps  

Energy Technology Data Exchange (ETDEWEB)

A state of the art review of two-phase void fraction models in smooth horizontal tubes is provided and a probabilistic two-phase flow regime map void fraction model is developed for refrigerants under condensation, adiabatic, and evaporation conditions in smooth, horizontal tubes. Time fraction information from a generalized probabilistic two-phase flow map is used to provide a physically based weighting of void fraction models for different flow regimes. The present model and void fraction models in the literature are compared to data from multiple sources including R11, R12, R134a, R22, R410A refrigerants, 4.26-9.58 mm diameter tubes, mass fluxes from 70 to 900 kg/m{sup 2} s, and a full quality range. The present model has a mean absolute deviation of 3.5% when compared to the collected database. (author)

2008-04-15

98

Design and performance of a solar-powered air-conditioning system in a green building  

Energy Technology Data Exchange (ETDEWEB)

A solar-powered adsorption air-conditioning system was designed and installed in the green building of Shanghai Research Institute of Building Science. The system contained 150 m{sup 2} solar collectors and two adsorption chillers with nominal refrigeration capacity of 8.5 kW. Based on performance characteristics of the adsorption chiller, the operation mode of the solar-powered air-conditioning system was optimized by maintaining a phase shift of 540 s between the two adsorption chillers. Thereafter, the whole system realized stable operation by the balance of heat consumption and refrigeration output. From June to August of 2005, the solar-powered air-conditioning system continuously ran between 9:00 and 17:00. The operation performance of the system under representative working condition showed that the average refrigeration output of the solar-powered air-conditioning system was 15.3 kW during an 8 h operation and the ...

2008-05-15

99

Indirect heating of natural gas using vapor chambers; Aquecimento indireto de gas natural com uso de camaras de vapor  

Energy Technology Data Exchange (ETDEWEB)

Operation safety and reliability are major guidelines in the design of city-gate units. Conventional natural gas heaters operate by a indirect mechanism, where liquid water is used to transfer heat by natural convection between the combustion chamber and the natural gas coil. In this work, the concept of vapor chamber is evaluated as an indirect gas heater. In a vapor chamber, liquid water is in contact with the heat source, and vaporizes. The vapor condenses in contact with the heat sink. A reduced scale model was built and tested in order to compare these two heating concepts where the combustion chamber was replaced by electrical cartridge heaters. This engineering model can operate either as a conventional heater or as a vapor chamber. The comparison between the concepts was done by inducing a controlled power to the cartridges and by measuring the resulting temperature ...

2005-07-01

100

A particulate model of solid waste incineration in a fluidized bed combining combustion and heavy metal vaporization  

Energy Technology Data Exchange (ETDEWEB)

This study aims to develop a particulate model combining solid waste particle combustion and heavy metal vaporization from burning particles during MSW incineration in a fluidized bed. The original approach for this model combines an asymptotic combustion model for the carbonaceous solid combustion and a shrinking core model to describe the heavy metal vaporization. A parametric study is presented. The global metal vaporization process is strongly influenced by temperature. Internal mass transfer controls the metal vaporization rate at low temperatures. At high temperatures, the chemical reactions associated with particle combustion control the metal vaporization rate. A comparison between the simulation results and experimental data obtained with a laboratory-scale fluid bed incinerator and Cd-spiked particles shows that the heavy metal vaporization is ...

2009-11-15

101

Pitfalls with the "chest compression-only" approach: the challenge of an unusual cause  

UK PubMed Central (United Kingdom)

Chest compression-only (CC-only) is now incorporated in the Norwegian protocol for dispatch guided CPR (cardiopulmonary resuscitation) in cardiac arrest of presumed cardiac aetiology.We present...Full Text Available

102

Effect of external pressure on intramuscular blood flow at rest and after running  

Energy Technology Data Exchange (ETDEWEB)

Local blood flow in the thigh was measured with /sup 133/Xe clearance technique in eight male distance runners after compression with a foam rubber compress and a standard elastic bandage. Two degrees of compression were tested, and an initial experiment with rested subjects was followed by a similar experiment immediately after running. Maximum compression exerted a cutaneous pressure of 85 (+/- 8) mm Hg and caused an immediate cessation of intra-muscular blood flow in the compressed area. Moderate compression gave a cutaneous pressure of 40 (+/- 5) mm Hg and resulted in a reduction of blood flow by approximately 50%. During compression, there were no significant differences in the blood flow of rested subjects compared to subjects immediately after running. In acute soft tissue injuries, a maximum compression bandage ...

1987-10-01

103

Drift compression and final focus systems for heavy ion inertial fusion  

Energy Technology Data Exchange (ETDEWEB)

Longitudinal compression of space-charge dominated beams can be achieved by imposing a head-to-tail velocity tilt on the beam. This tilt has to be carefully tailored, such that it is removed by the longitudinal space-charge repulsion by the time the beam reaches the end of the drift compression section. The transverse focusing lattice should be designed such that all parts of the beam stay approximately matched, while the beam smoothly expands transversely to the larger beam radius needed in the final focus system following drift compression. In this thesis, several drift compression systems were designed within these constraints, based on a given desired pulse shape at the end of drift compression systems were designed within these constraints, based on a given desired pulse shape at the end of drift compression. The occurrence of mismatches due to a rapidly ...

2001-05-01

104

Drift compression and final focus of intense heavy ion beams  

Energy Technology Data Exchange (ETDEWEB)

The longitudinal and transverse dynamics of a heavy ion fusion beam during the drift compression and final focus phase is studied. A lattice design with four time-dependent magnets is described that focuses the entire beam pulse onto a single focal point with the same spot size.

2003-05-01

105

Development of compression-controlled low-level laser probe system: towards clinical application  

UK PubMed Central (United Kingdom)

Various physico-chemical tissue optical clearing (TOC) methods have been suggested to maximize photon density in tissue. In order to enhance photon density, a compression-controlled low-level...Full Text Available

2010-09-01

106

Cold startability and blue and white smoke in a small direct injection diesel engine. (4th report) Effects of cetane number and compression ratio  

Energy Technology Data Exchange (ETDEWEB)

The improvement of startability achieved by chemical ignition promotion at low temperature was studied theoretically and experimentally in terms of compression ratio and cetane number using a small direct injection diesel engine. The findings are as follows: The compression ratio and cetane number vary almost linearly. When the compression ratio increases by 1, the cetane number decreases by about 9. Since almost the same ignition condition at starting can be achieved by adjusting the number of cranking cycles, there is almost no influence of compression ratio and cetane number on ignition delay. When the soak temperature is -10{sup 0}C and the compression ratio is 18, the influence of the cetane number is almost negligible. Given the same starting time, the influence produced by an increase in compression ratio by 1 is equivalent to the influence produced by a ...

1988-11-25

107

June 1966  

Science.gov (United States)

Ultimate Compressive Strength of Short Sheet-Stringer Panels With Special. Reference to the Influence of the Riveted Connection Between Sheet and. Stringer ...

108

Influence of HNS on the Microstructure and Properties of Cast ...  

Science.gov (United States)

... The ultimate compressive strength was measured, and values for Young's modulus were calculated from the linear portion of the test curve. ...

1981-04-01

109

Hollow Glass Filament Reinforced Plastics for Deep ...  

Science.gov (United States)

... Problems investigated in various basic hollowness ratios include ultimate compressive strength, fatigue properties, buckling characteristics, and ...

1966-02-08

110

Effect of Pressures up to 2.0 GPa on the Mechanical ...  

Science.gov (United States)

... hydrostatic pressures up to 700 MPa. The effect of pressure on the ultimate compressive strength is shown. The effect of size on ...

111

Crash-Resistant Crewseat Limit-Load Optimization through ...  

Science.gov (United States)

... populations ..... 63 34 Vertebral ultimate compressive strength for various populations ..... 64 35 ...

1986-01-01

112

Compressive and Torsional Buckling Behavior of Carbon Nanotube Bundles  

International Nuclear Information System (INIS)

The compressive and torsional buckling behavior of carbon nanotube bundles at room temperature is examined with classical molecular dynamics simulation. The critical compressive load and stiffness of a single carbon nanotube in the bundle are found to be similar to those of individual carbon nanotubes. However, the critical torsional moment and stiffness of a single carbon nanotube in the bundle are found to be higher than those of individual carbon nanotubes. In addition, this study demonstrates that van der Waals interactions between the nanotubes in the bundle significantly affect the critical compressive load of the nanotube bundle.

2007-08-01

113

Carbon Fiber Reinforced Glass Matrix Composites for Satellite ...  

Science.gov (United States)

... The ultimate compressive strength (UCS) for the HMU/BSG composite is essentially equivalent to the tensile strength exhibited by this system. ...

1992-06-01

114

Energy saver A-sector power test results  

Energy Technology Data Exchange (ETDEWEB)

The superconducting magnets and associated cryogenic components in A-sector represent the initial phase of installation of the Fermilab superconducting accelerator, designed to accelerate proton beams to energies of 1 TeV. Installation of the magnets, comprising one-eighth of the ring, was completed in December, 1981. Cooldown and power tests took place in the first half of 1982, concurrent with main ring use for 400 GeV high energy physics. The tests described in this paper involved 151 cryogenic components in the tunnel: 94 dipoles, 24 quadrupoles, 25 spool pieces, 3 feed cans, 4 turn-around boxes and 1 bypass. Refrigeration was supplied by three satellite refrigerators, the Central Helium Liquefier, and two compressor buildings. The magnets were powered by a single power supply.

1982-09-15

115

Air conditioning in high rise buildings; conditionnement d'air dans les immeubles de grande hauteur  

Energy Technology Data Exchange (ETDEWEB)

This book brings together the 103 presentations given at the 2. conference of the international institute of refrigeration (IIF/IIR) about air conditioning in high rise office buildings. The main themes are: design of air conditioning equipment for high buildings; air quality and thermal comfort inside these buildings; constraints and possible improvements of the refrigeration equipment used; energy conservation; fire protection and smokes detection. All themes are presented both on the technical and economical points of view and concern more particularly the buildings of Chinese cities. This publication is available both on the book and CD-Rom forms. (J.S.)

2000-07-01

116

Thermodynamic calculations for Otto cycle engines using methanol as a fuel  

Energy Technology Data Exchange (ETDEWEB)

Equations are derived to permit calculation of the work required for the isentropic compression of a two phase fuel-air mixture. Methanol evaporation during compression is shown to substantially reduce compression work and thereby improve cycle efficiency and maximum power. Effects of evaporative cooling in the intake manifold are calculated. 14 refs.

1981-01-01

117

Thermodynamic calculations for Otto cycle engines using methanol as a fuel  

Energy Technology Data Exchange (ETDEWEB)

Equations are derived to calculate the work required for the isentropic compression of a 2-phase fuel-air mixture. Methanol evaporation during compression substantially reduces compression work and improves cycle efficiency and maximum power. Effects of evaporative cooling in the intake manifold are calculated. Energy d. of methanol and gasoline fuel-air charges are compared. The phase equilibrium and evaporation rate are causes of the poor cold-starting performance of methanol.

1981-01-01

118

Shock compression temperature rise determined from resistivity of embedded metal foils. [Polymethyl methacrylate  

Energy Technology Data Exchange (ETDEWEB)

The temperature rise induced by shock compression of polymethyl methacrylate (PMMA) was determined from measurements of the electrical resistivity of embedded copper foils. The temperature of the copper was determined from the observed foil resistance and known values of the change in copper resistivity with temperature and shock compression. Temperature values obtained over a stress range from 0.9 to 6.0 GPa are in good agreement with thermocouple measurements reported previously.

1980-01-01

119

Apparatus for strengthening the face of an extraction working  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the invention is to improve adaptability of a compression shield to irregularities of a face. This goal is achieved in that a compressible shield is made in the form of a lattice of elastic transverse plates with grooves, elastic vertical elements installed in the grooves, and an elastic plate which is concave toward the face. The plate is located vertically in the middle of the shield. The compressible shield is attached by hinges to a deflector. Telescopic cross pieces are attached by hinges to the covering section of reinforcement, offering the possibility of longitudinal movement at the point of attachment.

1982-01-01

120

Dynamic response of a liquid-vapor interface during flow film boiling from a sphere  

Energy Technology Data Exchange (ETDEWEB)

Film boiling is the mode if boiling during which the hot surface is separated from the vaporizing liquid by a nearly continuous film vapor. Film boiling is usually considered a very undesirable boiling regime since it is a relatively quiet and inefficient mode of heat transfer, particularly as compared to nucleate boiling. It is customary to analyze the two-phase flow regime of laminar flow film boiling by assuming the two-phase flow regime of laminar flow film boiling by assuming an idealized vapor film flow characterized by a smooth liquid-vapor interface. However, during stable flow film boiling, the wavy nature of the liquid-vapor interface and its role in local heat and mass transport have been largely ignored. The vapor interface is rarely stationary. Interfacial waves may substantially augment the heat transfer rates throughout the layer. The present ...

1987-11-01

121

Temperature, moisture, and strain rate effects on the compressive mechanical behavior of Nylon 6/6  

Energy Technology Data Exchange (ETDEWEB)

Material test results are presented for the mechanical behavior of Nylon 66 in compression. Static compression modes include direct compression, stress relaxation and creep. Dynamic direct compression results are included. Tests are performed at atmospheric pressure; strain rates range from 10/sup /minus/4/sec to 10/sup 2/sec; temperatures are 20, 65, 110, 150 and 200/degree/C; moisture levels are 0% (dry), 2% and 6% (saturated); true strains to /minus/0.25 are imposed. Our empirical Temperature-Moisture equivalence of 14/degree/C per 1% moisture is discussed with respect to the /open quotes/free volume/close quotes/ concept.

1988-04-01

122

Determination of thrust compression systems with a multisource geoscientific data processing in the southern margin of Ordos basin, China  

Energy Technology Data Exchange (ETDEWEB)

In this paper, the multisource geoscientific data, such as TM data, NOAA data, the data of Bouguer gravity anomaly and aeromagnetic anomaly, the multisource geophysical processing methods, such as upward continuations, vertical derivative and gradient image, and synthetic image processing method - remote sensing image processing and geophysical image processing under I{sup 2}S600, are used to study the reverse faults or thrusts in the southern margin of Ordos basin, China. On the basis of these results and with geological investigation in the field, the authors have determined three thrust compression systems, named EW thrust compression system, NE thrust compression system and NW thrust compression system. These three systems reveal the regularity of geological structural evolution in the southern margin of Ordos basis and in the north side of Qinling Orogenic Belt.

1996-08-01

123

Steganography using wavelet compressed images  

Science.gov (United States)

Internet bandwidth is in high demand, and one way that web sites lower the amount of bandwidth they use is by compressing their site's images. This lowers the amount of bandwidth used, and makes the site load much faster. There are of course many other useful applications for compressed images. Bit Plane Complexity Segmentation (BPCS) digital picture steganography is a technique to hide data inside an image file. BPCS achieves high embedding rates with low distortion based on the theory that noise-like regions in a bit-plane can be replaced with noise-like secret data without discernible loss in image quality. This is possible because the human eye, while very good at distinguishing anomalies in areas of homogenous texture, is bad at distinguishing anomalies in visually complex areas. However, BPCS is not a robust embedding scheme, and any lossy compression usually destroys the data. Wavelet image ...

2001-08-01

124

Spiral Waves and Shocks in Discs around Black Holes: Low Compressibility and High Compressibility models  

Science.gov (United States)

Some authors have concluded that spiral structures and shocks do not develop if an adiabatic index gamma > 1.16 is adopted in accretion disc modelling, whilst others have claimed that they obtained well defined spirals and shocks adopting a gamma = 1.2 and a M_2/M_1 = 1 stellar mass ratio. In our opinion, it should be possible to develop spiral structures for low compressibility gas accretion discs if the primary component is a black hole. We considered a primary black hole of 8 solar mass and a small secondary component of 0.5 solar mass to favour spiral structures formations and possible spiral shocks via gas compression due to a strong gravitational attraction. We performed two 3D SPH simulations and two 2D SPH simulations and characterized a low compressibility model and a high compressibility model for each couple of simulations. 2D models reveal spiral structures existence. Moreover, spiral ...

2001-12-01

125

Compression ignition of hydrogen in a direct injection diesel engine modified to operate as a low-heat-rejection engine  

Energy Technology Data Exchange (ETDEWEB)

The feasibility of using hydrogen as the sole fuel in a direct injection diesel engine was investigated. An air cooled single cylinder Lister ST1 diesel engine was modified to operate as a low-heat-rejection engine for this study. Partially stabilized zirconia ceramic parts were used to shield the combustion space of the engine. Using a compression ratio of 17.9:1 and motoring the test engine at 21000 rpm, a maximum compression temperature of approximately 900 K was achieved. Under these operating conditions, all lubricants tested were found to burn. Lowering the speed to 1450 rpm and the compression ratio to 17.1, lubricant combustion and hot spots were successfully eliminated. The maximum compression temperature, when compression ignition of hydrogen was tried, was in the 800 K range. The corresponding ceramic surface temperature was estimated to reach 600-700 K. Only sporadic ...

1990-01-01

126

The European volcanic ash crisis: Between international and European law | EurActiv  

Wastenet

... Carbon capture and storage Waste Prevention and Recycling EU clean air strategy Environmental liability: Applying the 'polluter pays' principle What goes around ...comes around: Recycling and climate change Behind closed doors: Air quality in buildings Keeping cool with refrigerants: The F-gas review Regions fighting climate ...

127

ORNL `90  

Energy Technology Data Exchange (ETDEWEB)

This overview of research conducted at ORNL in 1991 presents information on the subjects of biology, physics, and the environment. Specific topics include gene mutations in kidney disease, technology assessments in thermonuclear fusion, submarine hunting technology, ozone-safe refrigerants, optical data storage via surface enhanced raman spectroscopy, and waste mitigating microbes. (GHH)

1990-12-31

128

ORNL '90  

Energy Technology Data Exchange (ETDEWEB)

This overview of research conducted at ORNL in 1991 presents information on the subjects of biology, physics, and the environment. Specific topics include gene mutations in kidney disease, technology assessments in thermonuclear fusion, submarine hunting technology, ozone-safe refrigerants, optical data storage via surface enhanced raman spectroscopy, and waste mitigating microbes. (GHH)

1990-01-01

129

Evaluation of synergistic effect in vacuum pack, refrigeration and irradiated treatments of minimally processed cassava; Avaliacao do efeito sinergistico da embalagem a vacuo, irradiacao e refrigeracao da mandioca minimamente processada  

Energy Technology Data Exchange (ETDEWEB)

Cassava is cultivated almost all over the world and it is considered one of the most important nutritious sources of calories in the human diet. Cassava is a viable food against starvation in several poor areas of the world because it is an extremely resistant culture and may reach satisfactory economical yield. We utilized vacuum packed industrialized cassava irradiated with 0,1 kGy, 3kGy and 5kGy and stored under refrigeration for 1, 21, 30 and 50 days. Our objective was to analyse the synergistic effect of vacuum packing, irradiation and refrigeration on the preservation of minimally processed cassava. The samples were analyzed for pH, acidity, weight, humidity, texture and color. The irradiation did not affect the chemical characteristics of the cassava. Neither the pH nor the acidity, the most relevant variables to verify deterioration in cassava, presented significant alterations during the period of storage. Comparing the irradiated ...

2005-07-01

130

Adsorption capability of charcoal: a comparison study of some activated and non-activated charcoal samples  

Energy Technology Data Exchange (ETDEWEB)

Experiments were carried out to determine the adsorption capability of some commercial activated and non-activated charcoal samples with methanol to select the most favourable pair to be used in a solar adsorption refrigeration system. The results obtained are presented. A simple method has been used to enhance the adsorption capability of the lumpwood charcoal. (Author)

1994-01-01

131

Uses of laser optical pumping to produce polarized ion beams  

Energy Technology Data Exchange (ETDEWEB)

Laser optical pumping can be used to produce polarized alkali atom beams or polarized alkali vapor targets. Polarized alkali atom beams can be converted into polarized alkali ion beams, and polarized alkali vapor targets can be used to produce polarized H/sup -/ or /sup 3/He/sup -/ ion beams. In this paper the authors discuss how the polarized alkali atom beams and polarized alkali vapor targets are used to produce polarized ion beams with emphasis on the production of polarized negative ion beams.

1983-04-01

132

Effects of vaporizer and evaporative-condenser size on geofluid effectiveness and cost of electricity for geothermal binary power plants  

Energy Technology Data Exchange (ETDEWEB)

A special study was conducted to investigate the influences of minimum approach temperature differences occurring in supercritical-heater/vaporizer and evaporative-condenser heat rejection systems on geothermal-electric binary power plant performance and cost of electricity. For the systems investigated optimum pinch points for minimizing cost of electricity were estimated to range from 5 to 7/sup 0/F for the heater vaporizer. The minimum approach of condensing temperature to wet-bulb temperature for evaporative condensers was estimated to be about 30/sup 0/F in order to achieve the lowest cost of electricity.

1983-10-01

133

Determination of vapor pressures, enthalpies of sublimation, and enthalpies of fusion of benzenetriols  

Energy Technology Data Exchange (ETDEWEB)

Molar enthalpies of sublimation of 1,2,4-, 1,2,3-, and 1,3,5-tri-hydroxy-benzene, were obtained from the temperature dependence of the vapor pressure measured by the transpiration method. The molar enthalpies of fusion and molar heat capacities of these compounds were measured by DSC. The measured data sets of vaporization, sublimation and fusion enthalpies were checked for internal consistency. Strength of the inter- and intra-molecular hydrogen bonding in di- and tri-hydroxy-benzenes have been assessed.

2004-06-07

134

chapter 5 - NASA's History Office  

Science.gov (United States)

Ever-present water vapor and dust distort or block incoming radiations. ... were among the first scientific sensors to be attached to the earliest space rockets. ...

135

Study on cold startability and mixture formation of high-percentage methanol blends  

Energy Technology Data Exchange (ETDEWEB)

Using gasoline as an example of additives for cold start improvement, fuel vapor composition of methanol-gasoline mixtures, fuel evaporation rate in consideration of temperature drop due to heat of fuel evaporation, air fuel ratio, stoichiometric air fuel ratio and excess air ratio of fuel vapor were calculated. The mixture formation of methanol-gasoline mixtures at low temperature in otto cycle engines was studied. Van Laar's empirical formula was used to estimate the partial pressure of high-percentage methanol blends. It was found that the most part of fuel vapor is occupied by gasoline, even when a small amount of gasoline is added to methanol resulting to an extremely small excess air ratio. It is obvious that this vapor pressure adjustment using gasoline is the dominant factor for improvement in cold startability. (10 figs, 1 tab, 10 refs)

1988-05-31

136

Parametric Modeling of Low-Frequency Water-Vapor-Induced ...  

Science.gov (United States)

indicated for the phase spectral density measurements; how- ever, Ref. 7 provides a very tentative estimate of : ORW ~ 2 ><10"'(RW); Ta = 1000 seconds ...

137

Numerical modeling of scanning laser-induced melting, vaporization and resolidification in metals subjected to step heat flux input  

Energy Technology Data Exchange (ETDEWEB)

We present a 1-D heat transfer, melting, vaporization and resolidification model describing the interaction of a scanning continuous-wave laser with a metal surface wherein the beam power is constant. A physical model based on the Stefan problem is developed with appropriate boundary conditions. The effects of processing parameters on process variables are investigated numerically by varying beam diameters, scan speeds and substrate temperatures for Nickel. Relations are derived for the times to initiate melting, to initiate vaporization, to reach maximum melting depth, for melting-resolidification, and for maximum melting and vaporization depths. Surface temperatures are compared with approximate closed form solutions. (Author)

2004-09-01

138

Nomographs estite floating-roof tank evaporation  

Energy Technology Data Exchange (ETDEWEB)

Nomographs are presented that estimate the evaporation loss from external floating-roof tanks using tank diameter, type of seal, product vapor pressure, and wind velocity.

1986-01-27

139

Interpolating atmospheric water vapor delay by incorporating terrain elevation information  

British Library Electronic Table of Contents (United Kingdom)

In radio signal-based observing systems, such as Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR), the water vapor in the atmosphere will cause delays during the signal transmission. Such delays vary significantly with terrain elevation. In the case when atmospheric delays are to be eliminated from the measured raw signals, spatial interpolators may be needed. By taking advantage of available terrain elevation information during spatial interpolation process, the accuracy of the atmospheric delay mapping can be considerably improved. This paper first reviews three elevation-dependent water vapor interpolation models, i.e., the Best Linear Unbiased Estimator in combination with the water vapor Height Scaling Model (BLUE?+?HSM), the Best Linear Unbiased Es...

2011-01-01

140

Instabilities during liquid migration into superheated hydrothermal systems  

Energy Technology Data Exchange (ETDEWEB)

Hydrothermal systems typically consist of hot permeable rock which contains either liquid or liquid and saturated steam within the voids. These systems vent fluids at the surface through hot springs, fumaroles, mud pools, steaming ground and geysers. They are simultaneously recharged as meteoric water percolates through the surrounding rock or through the active injection of water at various geothermal reservoirs. In a number of geothermal reservoirs from which significant amounts of hot fluid have been extracted and passed through turbines, superheated regions of vapor have developed. As liquid migrates through a superheated region of a hydrothermal system, some of the liquid vaporizes at a migrating liquid-vapor interface. Using simple physical arguments, and analogue laboratory experiments we show that, under the influence of gravity, the liquid-vapor interface may become unstable and break up into ...

1995-01-26

141

Fuel conversion apparatus and method  

Energy Technology Data Exchange (ETDEWEB)

Apparatus and method are described for the vaporization of liquid fuel oils to produce a gaseous mixture suitable for burning in a burner normally designed for operation utilizing natural gas.

1981-11-24

142

Excitonic transitions in InGaP/InAlGaP strained quantum wells  

Science.gov (United States)

Excitonic transitions in metalorganic vapor phase epitaxially grown In[sub [ital x

1993-08-30

143

Changes of atmospheric water vapor budget in the Pearl River basin and possible implications for hydrological cycle  

British Library Electronic Table of Contents (United Kingdom)

In this study, we thoroughly analyzed abrupt behaviors, trends, and periodicity properties of water vapor flux and moisture budget entering and exiting the four edges of the Pearl River basin based on the NCAR/NCEP reanalysis dataset by using the continuous wavelet transform and the simple two-phase linear regression technique. Possible implications for hydrological cycle and water resource management of these changes are also discussed. The results indicate that: (1) the water vapor propagating through the four edges of the Pearl River basin is decreasing, and it is particularly true for the changes of the water vapor flux exiting from the north edge of the study river basin. The transition point from increase to decrease occurs in the early 1960s; (2) The wavelet transform spectra indica...

2010-01-01

144

Anesthetic stimulation of insect water receptors.  

UK PubMed Central (United Kingdom)

Halothane, chloroform, and carbon tetrachloride, in the vapor and liquid phases, stimulate the water receptor of the blowfly Phormia regina. There are three successive phases of response to long-lasting...Full Text Available

1976-09-01

145

On the bending response of Kevlar 49/epoxy beams and rings  

Energy Technology Data Exchange (ETDEWEB)

Kevlar 49/epoxy laminates often exhibit substantial material nonlinearity when subjected to bending. This is a consequence of the yeild-like behavior of a Kevlar 49/epoxy lamina in fiber-directed compression. In this paper, analyses that utilize a simple idealization of compressive yielding are described and calculated results for Kevlar 49 reinforced beams and rings are compared with available data. First, results of a finite element analysis of a thin, unidirectionally reinforced ring subjected to diametral compression are presented. This analysis uses beam elements that incorporate linear tensile and elastic-perfectly plastic compressive behavior. Then a method used to analyze quasi-isotropic beams tested in four-point bending is discussed. This finite element analysis uses a layered shell element with a lamina constitutive model that permits elastic-perfectly plastic response to fiber-directed ...

1988-05-01

146

Equation of state of laser-shocked compressed iron; Equation d'etat du fer comprime par choc laser  

Energy Technology Data Exchange (ETDEWEB)

This thesis enters the field of highly compressed materials equation of state studies. In particular, it focuses on the case of laser shock compressed iron. This work indeed aims at getting to the conditions of the earth's core, comprising a solid inner core and a liquid outer core. The understanding of phenomena governing the core's thermodynamics and the geodynamic process requires the knowledge of iron melting line locus around the solid-liquid interface at 3.3 Mbar. Several experiments were performed to that extent. First, an absolute measurement of iron Hugoniot was obtained. Following is a study of partially released states of iron into a window material: lithium fluoride (LiF). This configuration enables direct access to compressed iron optical properties such as reflectivity and self-emission. Interface velocity measurement is dominated by compressed LiF optical properties and ...

2004-01-01

147

Effects of compression ratio on combustion characteristics of a direct-injection diesel engine  

Energy Technology Data Exchange (ETDEWEB)

The effects of compression ratio on the history of the fuel-burning process was investigated in a single-cylinder direct-injection diesel engine. Two compression ratios of 21.4 and 18.5 were studied by using two wide and shallow bowls. The engine was operated at different speeds and overall air-fuel ratios, but with constant start-of-combustion timing at top dead center. The measured cylinder pressure was used to derive fuel-burning rate. At all conditions, the low-compression-ratio bowl had a larger mass of premixed-burned fuel and a higher peak specific fuel-burning rate. The fuel-burning rate in the diffusion-controlled phase of combustion decreased with decreasing compression ratio. The resulting combustion duration became longer at reduced compression ratio, and the difference could be as large as 14 crank-angle degrees. For the engine conditions examined in this study, the ...

1987-01-01

148

Stakeholder acceptance analysis: In-well vapor stripping, in-situ bioremediation, gas membrane separation system (membrane separation)  

Energy Technology Data Exchange (ETDEWEB)

This document provides stakeholder evaluations on innovative technologies to be used in the remediation of volatile organic compounds from soils and ground water. The technologies evaluated are; in-well vapor stripping, in-situ bioremediation, and gas membrane separation.

1995-12-01

149

Second harmonic generation of copper-vapor pulsed laser radiation  

Energy Technology Data Exchange (ETDEWEB)

An experimental study of second harmonic generation in a copper-vapor pulsed laser with an ADP crystal is presented. The ratio of the conversion into the second harmonic is found to depend on the average power of the exciting radiation. The maximum conversion ratio was 8.5%. Thermal self-defocusing is the main obstacle to obtaining high average powers at the double frequency.

1980-08-01

150

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 regions of the heat ...

2008-09-30

151

Laser photochemical etching of molybdenum and tungsten thin films by surface halogenation  

Energy Technology Data Exchange (ETDEWEB)

Laser direct-write etching of the refractory metals Mo and W was developed using reactions in chlorine and nitrogen trifluoride vapors. Rate and high spatial resolution are simultaneously optimized using a two-vapor halogenation/development sequence, based on surface modification. Local-area laser chlorination of the metal surface is used to predispose areas to subsequent bulk etching.

1986-12-01

152

Double-electron-capture cross section for I/sup +/ in a magnesium-vapor target  

Energy Technology Data Exchange (ETDEWEB)

Measurements of the double-electron-capture process in which a positive ion of iodine becomes a negative ion in a single collision with a magnesium atom are reported between 20 and 90 keV. The cross section is comparable to that for the rare gases and not as large as might be expected from a two-valence-electron atom. This process is probably insignificant in the production of negative ion beams using a magnesium-vapor target.

1987-06-15

153

Chalk Point Cooling Tower Project. Environmental Systems Corporation's FY77 final report, July 1, 1976--August 31, 1977. Volume II. Cooling Tower Drift Dye Tracer Experiment. [Dye tests of vapor plume dispersion in coastal regions  

Science.gov (United States)

Results are reported from dye tests of the dispersion of the vapor plume from the natural draft cooling tower of a fossil-fuel power plant located in the coastal region of Maryland.

1977-12-01

154

Prediction of the compressive strength of vertebral bodies of the lumbar spine by quantitative computed tomography.  

Science.gov (United States)

The ultimate compressive strength of 36 thoracolumbar vertebrae was determined experimentally. In addition, the trabecular bone mineral content was measured by single energy quantitative computed tomography. The areas of fractured endplates were also determined by computed tomography. The results show that a linear relationship exists between the compressive strength and the product of bone density and endplate area. These data allow an in vivo prediction of vertebral body strength using a noninvasive method with a standard error of estimate amounting to less than 0.95 kN. PMID:3212488

1988-01-01

155

Magneto thermal convection in a compressible couple-stress fluid  

Energy Technology Data Exchange (ETDEWEB)

The problem of thermal instability of compressible, electrically conducting couple-stress fluids in the presence of a uniform magnetic field is considered. Following the linearized stability theory and normal mode analysis, the dispersion relation is obtained. For stationary convection, the compressibility, couple-stress, and magnetic field postpone the onset of convection. Graphs have been plotted by giving numerical values of the parameters to depict the stability characteristics. The principle of exchange of stabilities is found to be satisfied. The magnetic field introduces oscillatory modes in the system that were non-existent in its absence. The case of overstability is also studied wherein a sufficient condition for the non-existence of overstability is obtained. (orig.)

2010-03-15

156

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

157

Compression, bend, and impact testing of some tropical wood-polymer composites  

International Nuclear Information System (INIS)

The compressive and bending strengths of a local tropical wood (Kapur-Dryobalanop sp.) were improved significantly by suitable impregnation of polymeric monomers (methylmethacrylate, methylmethacrylate - 5% dioxane and vinyl acetate) into the wood cellular structure and subsequent irradiation to form a wood-polymer composite. Statistical analysis revealed a linear relationship between increase in the strengths and the percentage of polymer impregnated. Fractographic analysis of the impact fractured surfaces under the scanning electron microscope showed the nature of the wood-polymer interface, which could account for the increase in the compressive and bending strengths. (author).

1985-01-01

158

Back pain in the osteoporotic individual: A physiatric approach  

British Library Electronic Table of Contents (United Kingdom)

Back pain from osteoporosis is commonly related to compression fractures. The patient with vertebral compression fractures additionally suffers from an ongoing risk of recurrent fractures and postural abnormalities that can result in impaired respiratory function, leading to increased risk of morbidity. Weakened back muscles, especially the back extensor group, are felt to contribute significantly to this risk. The combination of pharmacologic and nonpharmacologic interventions, through physical activity, exercise, and modalities, are potential interventions that could be used to help reduce the pain of osteoporotic compression fractures as well as potentially reducing recurrent fracture rates.

2011-01-01

159

Auswirkung von Druckeigenspannungen in der Oberflaeche von Dampfturbinen-Scheiben auf das SpRK-Verhalten. Final Report. (Influence of residual compression stresses on the stress corrosion cracking behaviour of turbine rotor disc material. Final report).  

Science.gov (United States)

In this project the influence of residual compression stresses on the stress corrosion cracking behaviour of the turbine disc steel 26 NiCrMoV 14 5 (Rp(sub 0.2) = 850 N/mm(sup 2)) was investigated. The residual compression stresses were produced by shot p...

1988-01-01

160

Adsorption of mercury vapor on particles  

Energy Technology Data Exchange (ETDEWEB)

The adsorption of mercury vapor on particles was studied by using soot particles generated by incineration of sewage sludge (EP-ash) and activated carbon particles. Through the experiments, it was found that, at 298 K, the EP-ash has a fairly high adsorption capacity for mercury vapor in the order of 10/sup -6/g/g, which is between that of the ordinary soils and that of activated carbon particles. Furthermore, it was found that physical adsorption of mercury vapor on the studied particles at high temperature is described by Dubinin's equation. On the basis of the equation, it was shown that EP-ash physically adsorbs very little mercury at high temperature, and therefore, most mercury in the EP-ash is chemically adsorbed or contained in a form of mercury compounds. Nevertheless, the total amount of mercury contained in the particles is very little compared to the total mercury in the exhaust gases so that most ...

1986-07-01

161

Transient / Structural Analysis of a Combustor under Explosive Loads  

Science.gov (United States)

Ultimate Compressive Strength = 3000.0 psi. 3.0 Failure Criteria. The structural criteria used to evaluate the combustor components was chosen ...

162

The Effect of Boron on the Mechanical Behavior of Copper ...  

Science.gov (United States)

... 500 ppm, boron increases the 0.2% offset strength; results show that boron doping does not appreciably affect ultimate compressive strength; for 0 ...

163

Structure and Mechanical Properties of Boron-Doped Cubic ...  

Science.gov (United States)

... by the boron doping in most of the alloys except for Al66Mn9Zr25 + 50 ppm B alloy; permanent deformation at ultimate compressive strength is not ...

164

STUDIES ON THE EFFECT OF COMPRESSION ON RATE OF ...  

Science.gov (United States)

... ERH moisture cesteats are aumharized on Tables 20 and 21. Moisture sorption isotherme are shewn in Figures XXXI and XXXII. 17 Page 33. ...

1965-04-01

165

Nutcracker Phenomenon and Nutcracker Syndrome  

UK PubMed Central (United Kingdom)

Nutcracker phenomenon refers to compression of the left renal vein, most commonly between the aorta and the superior mesenteric artery, with impaired blood outflow often accompanied by distention...Full Text Available

2010-06-01

166

Metronome to Coordinate the Breaths and Cardiac Compressions Delivered by Minimally-Trained Caregivers During Two-Person CPR  

Science.gov (United States)

Astronaut crew medical officers (CMO) aboard the International Space Station (ISS) receive 40 hours

2005-01-01

167

Large Eddy Simulation of Supersonic Turbulent Flow in ...  

Science.gov (United States)

... AGARD AR-319, Volume 2. Knight, D., Zhou ... a Turbulent Boundary Layer in a Supersonic Flow. ... of Development of Separated Flows in Compression ...

2001-08-01

168

Influence of salt and elevated-temperature exposure on the maximum ...  

Science.gov (United States)

Ultimate Compressive Strength of Short Sheet - Stringer Panels With Special. Reference to the Influence of the Riveted Connection Between Sheet and Stringer ...

170

General Disclaimer One or more of the Following Statements may ...  

Science.gov (United States)

Wit?,-grain ultimate compressive strength of multiply extruded graphite rods made with G-18 flour,. V. 5. " TOTAL n ACCESSIBLE TO Hp AT 2600 psi ...

171

Fifteen-year follow-up of a patient with beta thalassaemia and extramedullary haematopoietic tissue compressing the spinal cord  

Energy Technology Data Exchange (ETDEWEB)

A long-term follow-up of a patient with beta thalassaemia with intra- and extraspinal extramedullary haematopoietic tissue compressing the spinal cord is presented. Extramedullary haematopoietic nodules are a rare cause of spinal cord compression and should be included in the differential diagnosis, especially in patients from Mediterranean countries. Treatment with radiation therapy solely failed, giving rise to the need of surgical intervention. Surgical decompression of the spine and the removal of the culprit lesion compressing the spine were performed. Postinterventional radiation therapy was applied to the spine. A relapse had to be treated again by surgical means combined with postinterventional radiation therapy. A complete relief of the symptoms and control of the lesion could be obtained.

2005-04-01

172

Far-out Pathways to Space: Great Guns? - ISTP  

Science.gov (United States)

The SHARP cannon. Hydrogen is compressed in the tube on top, the gun barrel is on bottom. When Jules Verne wrote in 1865 "From Earth to the Moon" he ...

173

Far-out Pathways to Space: Great Guns?  

Science.gov (United States)

Turbine Afterword The SHARP cannon. Hydrogen is compressed in the tube on top, the gun barrel is on bottom. When Jules Verne wrote in 1865 "From Earth to the Moon" he envisioned...

2011-09-03

175

Effective thermal conductivity and thermal contact resistance of gas diffusion layers in proton exchange membrane fuel cells. Part 2: Hysteresis effect under cyclic compressive load  

British Library Electronic Table of Contents (United Kingdom)

Heat transfer through the gas diffusion layer (GDL) is a key process in the design and operation of a PEM fuel cell. The analysis of this process requires the determination of the effective thermal conductivity as well as the thermal contact resistance between the GDL and adjacent surfaces/layers. The Part 1 companion paper describes an experimental procedure and a test bed devised to allow separation of the effective thermal conductivity and thermal contact resistance, and presents measurements under a range of static compressive loads. In practice, during operation of a fuel cell stack, the compressive load on the GDL changes. In the present study, experiments are performed on Toray carbon papers with 78% porosity and 5% PTFE under a cyclic compressive load. Results show a significant hy...

2010-01-01

176

Discrete Element Method for Modeling Penetration  

Science.gov (United States)

... In fact, for dynamic loading, the ultimate compressive strength can be more than doubled (Bischoff and Perry 1991), whereas the ultimate uniaxial ...

2006-07-01

177

Design and Evaluation of a Reinforced Advanced-Grid ...  

Science.gov (United States)

... kg/m3 density. The Rohacell foam displayed an average ultimate compressive strength of 1546 kPa. The maximum load ...

2011-05-14

178

DYNAMIC TESTS OF MODEL CONCRETE.  

Science.gov (United States)

... 4 maximum aggregate size. The effects of strain rate (up to 2.5 in./in./sec) on ultimate compressive strength were obtained. ...

1969-11-01

179

Compression Behavior of Fluted ... - NASA Technical Reports Server  

Science.gov (United States)

Traditional composite sandwich panels are composed of inner and outer facesheets separated by a core material such as balsa wood, polymeric foam, ...

180

Compressing DNA sequence databases with coil  

UK PubMed Central (United Kingdom)

BackgroundPublicly available DNA sequence databases such as GenBank are large, and are growing at an exponential rate. The sheer volume of data being dealt with presents serious...Full Text Available

181

CPR - adult  

Science.gov (United States)

Cardiopulmonary resuscitation - adult; Rescue breathing and chest compressions - adult; Resuscitation - cardiopulmonary - adult ... CPR can be lifesaving, but it is best performed by those who have been trained in an ...

182

Buffet Active Control - Experimental and Numerical Results  

Science.gov (United States)

... high- lift separated compressible flows over airfoils ... Proceedings AGARD-CP- 515, paper 26, Symposium ... Viscous-inviscid flow matching Analysis of ...

2001-06-01

183

Buckling and ultimate capability of plates and stiffened panels in axial compression  

British Library Electronic Table of Contents (United Kingdom)

This paper presents extensive non-linear finite element (FE) analysis and formulation development work carried out on the ultimate compressive strength of plates and stiffened panels of ship structures. A review of contemporary designs for large ships was carried out. The existing formulae for plate ultimate compressive strength were reviewed and compared with non-linear FE analysis results. A semi-analytical formula for ultimate compressive strength assessments of stiffened panels was proposed and is described. The developed formula was verified against results using ABAQUS non-linear FE software for a series of 61 stiffened panels and a good agreement between the proposed formula and FE results were achieved. The method was verified against a large number of published FE results and was ...

2009-01-01

184

A Bibliography of the Physical Equilibria and Related ...  

Science.gov (United States)

... 3. Critical constants, and triple point 4. Compressibility isothermE S. Density, molar volume (of a condensed phase) 6. Equations of state, general ...

1960-05-01

185

" N/ A - NASA Technical Report Server (NTRS)  

Science.gov (United States)

reaching their ultimate compressive strength. Thus, when applying a lamina stress analysis in conjunction with a failure model, one must ...

186

Stirling cooler ILK 15 - refrigeration of 15 W at 80 W; Stirlingkuehler ILK 15 - Kaeltemaschine fuer 15 W bei 80 K  

Energy Technology Data Exchange (ETDEWEB)

The stirling cryocooler ILK 15 is a machine with simple drive concept. This machine works with a conventional built-in electric motor and crank drive and needs a power input of about 500 W. The refrigerating capacity is 15 W at 80 K with a cooldown time of 12 minutes. The cooler is somehow a replacement for the Gifford-McMahon cycle coolers, which are bigger and heavier. The Stirling cryocooler was designed to cool HTSC-components. (orig.) [Deutsch] Der Stirlingkuehler ILK 15 ist eine Kaeltemaschine mit einfachem Antriebskonzept. Die Maschine arbeitet mit einem konventionellen Elektroeinbaumotor und Kurbeltrieb. Sie benoetigt eine Antriebsleistung von 500 W und hat eine Kaelteleistung von 15 W bis 80 K und eine Einkuehlzeit von 12 Minuten. Die Maschine kann als Alternative zur wesentlich groesseren und schweren Gifford-McMahon-Maschine gesehen und bei der Kuehlung von HTSL-Komponenten eingesetzt werden. (orig.)

1998-11-01

187

Performance characteristics of a natural circulation cooling/latent heat storage system  

Energy Technology Data Exchange (ETDEWEB)

A cooling system was developed which could be used even in such areas where the maximum and minimum temperatures of a day might differ widely. The system features in that a latent heat storage unit is connected to the natural circulation cooling unit consisting of 2 heat exchangers where condensed gas (refrigerant) which performs gas-liquid change has been sealed, enabling to cool objects night and day without the requirement for any power source. Electronic equipment was installed in an insulated shelter. Lauric acid and refrigerant R-22 were used as the latent heat storage medium and the heat transport medium respectively. Natural convection heat transfer performance of the outside surfaces of the condenser and the evaporator and the transient behavior of the system during the melting and solidification periods of the latent heat storage medium were tested. As a result of a 48 hour simulation experiment with load conditions set basing on the ...

1987-09-25

188

Magnetic liquefier for hydrogen  

Energy Technology Data Exchange (ETDEWEB)

This document summarizes work done at the Astronautics Technology Center of the Astronautics Corporation of America (ACA) in Phase 1 of a four phase program leading to the development of a magnetic liquefier for hydrogen. The project involves the design, fabrication, installation, and operation of a hydrogen liquefier providing significantly reduced capital and operating costs, compared to present liquefiers. To achieve this goal, magnetic refrigeration, a recently developed, highly efficient refrigeration technology, will be used for the liquefaction process. Phase 1 project tasks included liquefier conceptual design and analysis, preliminary design of promising configurations, design selection, and detailed design of the selected design. Fabrication drawings and vendor specifications for the selected design were completed during detailed design. The design of a subscale, demonstration magnetic hydrogen liquefier represents a significant ...

1992-12-31

189

Development of large-capacity refrigeration at 1.8 K for the Large Hadron Collider at CERN  

CERN Document Server

CERN, the European Laboratory for Particle Physics, is working towards the construction of the Large Hadron Collider (LHC), a high-energy, high-luminosity particle accelerator and collider [1] of 26.7 km circumference, due to start producing frontier physics, by bringing into collision intense proton and ion beams with centre-of-mass energies in the TeV-per-constituent range, at the beginning of the next century. The key technology for achieving this ambitious scientific goal at economically acceptable cost is the use of high-field superconducting magnets using Nb-Ti conductor operating in superfluid helium [2]. To maintain the some 25 km of bending and focusing magnets at their operating temperature of 1.9 K, the LHC cryogenic system will have to produce an unprecedented total refrigeration capacity of about 20 kW at 1.8 K, in eight cryogenic plants distributed around the machine circumference [3]. This has requested the undertaking of an industrial development ...

1996-01-01

190

Active packaging of ground beef patties by edible zein films incorporated with partially purified lysozyme and Na2EDTA  

British Library Electronic Table of Contents (United Kingdom)

Summary In this study, antimicrobial activity of zein films incorporated with partially purified lysozyme and disodium ethylenediaminetetraacetic acid (Na2EDTA) has been tested on selected pathogenic bacteria and refrigerated ground beef patties. The developed films containing 700-g-cm-2 lysozyme and 300-g-cm-2 Na2EDTA showed antimicrobial activity on Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella typhimurium. The application of lysozyme and Na2EDTA incorporated zein films on beef patties significantly decreased total viable counts (TVC) and total coliform counts after 5-days of storage compared to those of control patties (P-2EDTA or Na2EDTA alone significantly slowed down the oxidative changes in patties during storage (P-P-2EDTA for active packaging of refrigerated mea...

2011-01-01

191

Use and disposal of large home electronic appliances in Vietnam  

British Library Electronic Table of Contents (United Kingdom)

In this study, e-waste flows of five large home appliances (color televisions, refrigerators, washing machines, personal computers, and air conditioners) in Vietnam are investigated. A social survey was performed to investigate the situation on using appliances in households as well as on the disposal of appliances by the first users. Future quantities of e-waste were estimated using a model that combines use of the Weibull distribution, the logistic function, and the population balance model. It was forecast that about 3.86 million appliances, or 114 000 tons, will be discarded in 2010, and about 17.2 million appliances, or 567 000 tons, in 2025, showing a rapid increase of e-waste in the near future.

2009-01-01

192

On the thermal stabilization of the residual austenite in the cold upsetting steel 100Cr6  

Energy Technology Data Exchange (ETDEWEB)

Once again residual austenite as one component of the microstructure of steels is the basis for discussion among experts. Very often the phenomen of the stabilisation of residual austenite is the focus of interest. In this paper the influence of ageing on residual austenite transformations is discussed, with ageing taking place in a temperature range between ambient and M/sub s/-temperature after quenching from different austenitizing temperatures by means of subzero refrigeration. Results which are typical for 100Cr6 steel are presented and discussed.

1988-07-01

193

LUCIFER, a potentially background-free approach to the search for neutrinoless double beta decay  

British Library Electronic Table of Contents (United Kingdom)

LUCIFER (Low-background Underground Cryogenic Installation For Elusive Rates) is a new project for the study of neutrinoless Double Beta Decay, based on the technology of scintillating bolometers. These devices promise a very efficient rejection of the alpha background, opening the way to a virtual background-free experiment if candidates with a transition energy higher than 2615 keV are investigated. The baseline candidate for LUCIFER is 82Se. This isotope will be embedded in ZnSe crystals grown with enriched selenium and operated as scintillating bolometers in a low-radioactivity underground dilution refrigerator. In this paper, the LUCIFER concept will be introduced. The sensitivity and the very promising prospects related to this project will be discussed.

2011-01-01

194

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

195

Compact heat exchangers for condensation applications: Yesterday, today and tomorrow  

Energy Technology Data Exchange (ETDEWEB)

Compact heat exchangers are being increasingly considered for condensation applications in the process, cryogenic, aerospace, power and refrigeration industries. In this paper, different configurations available for condensation applications are analyzed and the current state-of-the-knowledge for the design of compact condensers is evaluated. The key technical issues for the design and development of compact heat exchangers for condensation applications are analyzed and major advantages are identified. The experimental data and performance prediction methods reported in the literature are analyzed to evaluate the present design capabilities for different compact heat-exchanger configurations. The design flexibility is evaluated for the development of new condensation applications, including integration with other process equipment.

1993-07-01

196

A preliminary design for a one GHz NMR spectrometer magnet  

International Nuclear Information System (INIS)

The authors have performed a preliminary design for a persistent GHz NMR magnet at 23.5 T and 1.8 K operating conditions. In this paper the authors shall address the issues of realistic conductor selection, the coil design, the magnetic and mechanical analysis of the coil, and the required field uniformity. In addition, they shall describe the GHz magnet cryostat with a practical 1.8 K J-T refrigerator system. Finally vibration isolation system and field shield design and its associated field harmonics will be analyzed.

1993-09-20

197

Advanced Underground Gas Storage Concepts: Refrigerated-Mined Cavern Storage, Final Report  

Energy Technology Data Exchange (ETDEWEB)

Over the past 40 years, cavern storage of LPG's, petrochemicals, such as ethylene and propylene, and other petroleum products has increased dramatically. In 1991, the Gas Processors Association (GPA) lists the total U.S. underground storage capacity for LPG's and related products of approximately 519 million barrels (82.5 million cubic meters) in 1,122 separate caverns. Of this total, 70 are hard rock caverns and the remaining 1,052 are caverns in salt deposits. However, along the eastern seaboard of the U.S. and the Pacific northwest, salt deposits are not available and therefore, storage in hard rocks is required. Limited demand and high cost has prevented the construction of hard rock caverns in this country for a number of years. The storage of natural gas in mined caverns may prove technically feasible if the geology of the targeted market area is suitable; and economically feasible if the cost and convenience of service is competitive with alternative available ...

1998-09-30

198

Formation of organic thin film by hot wall vapor deposition. Hot wall jochakuho ni yoru yuki usumaku no keisei  

Energy Technology Data Exchange (ETDEWEB)

The process operation of the hot wall vapor deposition method, formation of dry organic thin film and the control of molecular arrangement were described. This equipment included a substrate on the upper end of the hot wall tube and the vapor source at the lower end. The remarkable features are the hot wall tube which plays the role to hold vaporizing molecules to the high temperature and to transport molecules, and the flip flop mechanism which gives some idle period for the molecular vaporization by shutter closing. Several experiments were carried out by using stearic acid and by changing the distance S from the upper end of hot wall quartz tube to the substrate, the furnace temperature T{sub f} and the substrate temperature T{sub s}. When T{sub f} is equal to or less than the melting point of stearic acid, molectles are preferentialy made to vertical arrangement. In the case of T{sub f} more than ...

1991-12-01

199

The influence of process parameters on forged magnesium alloys  

Energy Technology Data Exchange (ETDEWEB)

Two extruded magnesium alloys, AZ31 and AZ61 were selected to evaluate the influence of process parameters on the material forgeability. The processing parameters considered for forging magnesium alloys were: compression load in the range 55 KN to 60 KN and forging temperature, in the range of ambient temperature to 300 C. Uniaxial compression tests were conducted to establish the strain-temperature relationship. The influences of process parameters on the microstructure were also evaluated. (orig.)

2003-07-01

200

Structure and properties of high-performance polymeric and carbon fibers - an overview  

Energy Technology Data Exchange (ETDEWEB)

In this paper structure and mechanical properties of PBZT and PBO fibers are briefly discussed. One limitation of the high-modulus polymeric fibers and ultrahigh-modulus carbon fibers in reinforced composites is their poor compressive strength. Issues related to the compressive strength of polymeric and carbon fibers are considered. 62 references, 7 figures, 4 tables.

1989-01-01

201

Fatal left cardiac failure caused by external compression of left internal mammary artery graft in an accident: a case report  

UK PubMed Central (United Kingdom)

We report for the first time a case of a 54 years old man with a fatal motorcycle accident due to an external bleeding compression of left internal mammary artery graft to the left anterior descending...Full Text Available

202

Data compression using artificial neural networks  

Energy Technology Data Exchange (ETDEWEB)

This thesis investigates the application of artificial neural networks for the compression of image data. An algorithm is developed using the competitive learning paradigm which takes advantage of the parallel processing and classification capability of neural networks to produce an efficient implementation of vector quantization. Multi-Stage, tree searched, and classification vector quantization codebook design are adapted to the neural network design to reduce the computational cost and hardware requirements. The results show that the new algorithm provides a substantial reduction in computational costs and an improvement in performance.

1991-09-01

203

Combustion chamber layout for modern Otto engines  

Energy Technology Data Exchange (ETDEWEB)

Since the most efficient way to improve fuel economy in the part-load range is to increase the compression ratio, emphasis is placed on combustion chambers allowing high compression ratios combined with low octane requirements. According to Porsche experience, many demands can be met in the simplest manner by locating the combustion chamber in the piston crown. This configuration offers various advantages over its counterpart installed in the cylinder head. 24 refs.

1981-10-01

204

Measurement of swirling flow in direct injection diesel engine (Part 1). Effect of intake port geometry and engine speed  

Energy Technology Data Exchange (ETDEWEB)

Swirling speed in a direct injection diesel engine was measured by a laser doppler velocimeter. Intake port geometry and engine speed were changed as factors affecting the swirling flow to study the distribution of swirling flow speed. The distribution of swirling flow speed changes complicatedly owing to axial nonsymmetry during intake process but becomes simple shape of axial symmetry during compression process after closing intake valve. But if this is assumed as the rigid swirl shape, the difference due to each intake port cannot be expressed but also large error may be possible to appear close to the cylinder wall. The distribution of swirling flow speed during compression process changes similarly, nearly proportinal to engine speed. But the similarity is higher at the middle period in compression process than at the end period in compression period. Axial distribution of local swirling ratio ...

1989-05-31

205

Evaluation of advanced technologies for power transformers. Final report  

Energy Technology Data Exchange (ETDEWEB)

The high insulating strength of certain gases, such as sulfur hexafluoride, when used at high pressure, suggests that there may be advantages to compressed gases as the insulating fluid in power transformers. However, simply exchanging the oil for compressed gas in an otherwise conventional transformer design will not yield a significant overall advantage. Compressed gases present the engineer with properties which are quite different from mineral oil. If gases are to be used as the major insulating fluid in power transformers, then virtually all aspects of the insulation and cooling of the apparatus must be reconsidered, affording an opportunity to introduce new design concepts, new materials, and new construction techniques. In this program, the feasibility of using the following principal design concepts has been explored: sheet conductors for the windings; a system of sealed, self-contained, annular cooling ducts ...

1981-01-01

206

Compressors for compressed air technique at the Hanover Fair; Komprimiertes Angebot - Kompressoren fuer die Drucklufttechnik auf der Hannover Messe  

Energy Technology Data Exchange (ETDEWEB)

Suppliers of systems and components for compressed air technique were shown at the Hanover Fair 94 in Hall 5. On about 6000 m{sup 2} floor area, they showed their product range, which covered the whole range of compressed air technique from compressors via equipment for providing and storing the compressed air to compressed air tools. (orig.) [Deutsch] Die Anbieter von Systemen und Komponenten fuer die Drucklufttechnik waren auf der Hannover-Messe `94 in der Halle 5 zu finden. Dort zeigten sie auf rund 6000 m{sup 2} ihre Produktpalette, die von Kompressoren ueber die Geraete zum Aufbereiten und Speichern der Druckluft bis zu Druckluftwerkzeugen reichte und den gesamten Bereich der Drucklufttechnik abdeckte. (orig.)

1994-06-20

207

Changes in dielectric properties of Pb(In{sub 1/2}Nb{sub 1/2})O{sub 3}-PbTiO{sub 3} ceramics under compressive stress applied parallel and perpendicular to an electric field  

Energy Technology Data Exchange (ETDEWEB)

The influences of compressive stress on the dielectric properties of (1 - x)Pb(In{sub 1/2}Nb{sub 1/2})O{sub 3}-xPbTiO{sub 3} (x = 0.1-0.5) ceramics was investigated in this study. The dielectric properties were measured under compressive stress applied parallel and perpendicular to electric field. The results clearly showed that the superimposed compression stress had pronounced effects on the dielectric properties of PIN-PT ceramics. In general, with increasing compressive stress the dielectric constant of the ceramics increased and decreased when the stress was applied parallel and perpendicular, respectively, to the electric field direction. The dielectric loss tangent, however, decreased in both stress cases. The observations were mainly interpreted in terms of competing influences of the domain switching through non-180 deg. domain walls, clamping of domain walls, de-ageing and the stress-induced ...

2008-04-21

208

Vapor fraction measurements in a steam-water duct at atmospheric pressure using neutron radiography  

Energy Technology Data Exchange (ETDEWEB)

Real-time neutron radiography has been used to study the dynamic behavior of two-phase flow and measure vapor fractions in a steam-water duct at atmospheric pressure. This unique experimental technique offers one the opportunity to observe and record on videotape now Patterns and transient behavior of two-phase flow inside opaque containers without perturbing the environment. The neutron radiographic technique is non-intrusive and requires no special transparent window region. Data are recorded simultaneously over a large area of interest. Image processing of the video data can be employed to measure bubble velocities and time-averaged and Instantaneous vapor fractions.

1994-11-11

209

Turn-key Raman lidar for profiling atmospheric water vapor, clouds, and aerosols at the US Southern Great Plains Climate Study Site  

Energy Technology Data Exchange (ETDEWEB)

There are clearly identified scientific requirements for continuous profiling of atmospheric water vapor at the Department of Energy, Atmospheric Radiation Measurement program, Southern Great Plains CART (Cloud and Radiation Testbed) site in northern Oklahoma. Research conducted at several laboratories has demonstrated the suitability of Raman lidar for providing measurements that are an excellent match to those requirements. We have developed and installed a ruggedized Raman lidar system that resides permanently at the CART site, and that is computer automated to eliminate the requirements for operator interaction. In addition to the design goal of profiling water vapor through most of the troposphere during nighttime and through the boundary layer during daytime, the lidar provides quantitative characterizations of aerosols and clouds, including depolarization measurements for particle phase studies.

1997-12-31

210

Quantitative model of vapor dominated geothermal reservoirs as heat pipes in fractured porous rock  

Science.gov (United States)

We present a numerical model of vapor-dominated reservoirs which is based on the well-known conceptual model of White, Muffler, and Truesdell. Computer simulations show that upon heat recharge at the base, a single phase liquid-dominated geothermal reservoir in fractured rock with low matrix permeability will evolve into a two-phase reservoir with B.P.D. (boiling point-for-depth) pressure and temperature profiles. A rather limited discharge event through cracks in the caprock, involving loss of only a few percent of fluids in place, is sufficient to set the system off to evolve a vapor-dominated state. The attributes of this state are discussed, and some features requiring further clarification are identified. 26 refs., 5 figs.

1985-03-01

211

Preliminary assessment of condensation behavior for hydrocarbon-vapor expansions which cross the saturation line near the critical point  

Energy Technology Data Exchange (ETDEWEB)

Previous analyses of binary cycles for conversion of geothermal energy from moderate temperature resources to electrical energy have shown potential gains in net geofluid effectiveness of on the order of 8%, resulting from selection of turbine-expansion processes whose equilibrium states pass through the two-phase region (assuming major condensation does not occur). If condensation occurs, this gain could be reduced or eliminated by the resulting loss in turbine efficiency. Experience with many fluids, however, indicates that vapor supersaturation (or subcooling) permits metastable pure-vapor states to exist at temperatures considerably below the saturation temperature at a given pressure; thus, by better understanding the condensation process, and properly structuring the cycle, substantial performance gains may be achievable. The present study assessed, qualitatively, the probability for attaining this performance gain.

1982-07-01

212

Health-hazard evaluation report HETA 86-132-1780, Alyeska Pipeline Service Company, Valdez, Alaska  

Energy Technology Data Exchange (ETDEWEB)

A study was made of employee exposure to oil sludge and vapors during oil-sludge removal and maintenance activities at the Alyeska Pipeline Service Company's Ballast Water Treatment Facility, Valdez, Alaska. Total hydrocarbons, except benzene, toluene, and xylene, showed concentrations from 371 to 1228mg/m3. Of eight maintenance workers, five reported headache, dizziness, or nausea when working without a respirator. The authors conclude that workers were potentially exposed to benzene vapors and total hydrocarbon vapors exceeding the evaluation criteria for these substances. The authors recommend the use of respiratory protection measures to reduce exposures during work operations.

1987-02-01

213

Gibbs ensemble Monte Carlo simulations of coexistence properties of a polarizable potential model of water  

Energy Technology Data Exchange (ETDEWEB)

The liquid/vapor coexistence density, the partial vapor pressure, and the heat of vaporization were calculated using Gibbs ensemble Monte Carlo simulation techniques. Long-range interactions such as charge-charge, charge-dipole, and dipole-dipole were evaluated using Ewald summation techniques. A polarizable potential model was used to describe the water-water interactions (Dang and Chang, J. Chem. Phys. 106, 8149, 1997). The model yields good agreement with the corresponding experimental data in the lower temperature region and moderate agreement in the higher temperature region. The critical temperature and density were estimated to be 565 K and 0.28 g/cm3.

2001-12-01

214

Effect of different treatments on acid centers of very high silicon zeolites studied by ir spectroscopy  

Science.gov (United States)

Using the infrared spectroscopy method, we have studied the effect of thermal dehydration (under vacuum and in air) and treatment with water vapor on the acid centers of very high silicon zeolites of the ZSM type. We have shown that dehydration under vacuum and in air completely and irreversibly removes the OH groups at 1120/sup 0/K, while treatment with water vapor removes these groups at 770/sup 0/K. The Lewis acid centers of dehydrated zeolites (represented by two types of centers) are more heat-stable than the Bronsted acid centers, but the vapor treatment at 1020/sup 0/K leads to the disappearance of the Lewis acid centers. In this work, we discuss the reasons for destruction of the acid centers of the zeolites under different treatment conditions.

1986-08-01

215

Dynamic and static error analyses of neutron radiography testing  

Energy Technology Data Exchange (ETDEWEB)

Neutron radiography systems are being used for real-time visualization of the dynamic behavior as well as time-averaged measurements of spatial vapor fraction distributions for two phase fluids. The data in the form of video images are typically recorded on videotape at 30 frames per second. Image analysis of he video pictures is used to extract time-dependent or time-averaged data. The determination of the average vapor fraction requires averaging of the logarithm of time-dependent intensity measurements of the neutron beam (gray scale distribution of the image) that passes through the fluid. This could be significantly different than averaging the intensity of the transmitted beam and then taking the logarithm of that term. This difference is termed the dynamic error (error in the time-averaged vapor fractions due to the inherent time-dependence of the measured data) and is separate from the static error (statistical ...

1999-03-01

216

Characterization of physically vapor deposited AF2400 thin films  

Energy Technology Data Exchange (ETDEWEB)

Anti-reflective coatings made with Teflon AF2400 had the highest damage thresholds recorded for physical vapor deposited coatings at the Lawrence Livermore National Laboratory damage facility. Physical vapor deposited layers of Teflon AF2400, a perfluorinated amorphous polymer, maintained the bulk optical properties of a high transmittance from 200 nm to 1600 nm, and a low refractive index. In addition, the refractive index can be intentionally reduced by control of two common deposition parameters, deposition rate and substrate temperature. Scanning electron microscopy and nuclear magnetic resonance observations indicated that morphological changes caused the variations in the refractive index rather than compositional changes. The coatings adhered to fused silica and silicon wafers under normal laboratory handling conditions.

1993-11-01

217

Analysis of plasma treatment and vapor heat treatment for thin-film transistors by extracting trap densities at front and back interfaces  

International Nuclear Information System (INIS)

Hydrogen (H) plasma treatment, oxygen (O) plasma treatment and water (H_2O)-vapor heat treatment for polycrystalline-silicon (poly-Si) thin-film transistors (TFTs) have been analyzed by separately extracting trap density at a front silicon-oxide interface (D_F) and trap density at a back interface (D_B). It is found that the H plasma treatment is apt to generate D_F and D_B. The O plasma treatment reduces D_F, while the H_2O-vapor heat treatment reduces both D_F and D_B. Improvement of transistor characteristics of poly-Si TFTs depends on understanding these results.

2004-05-17

218

Universal model for water costs of gas exchange by animals and plants  

UK PubMed Central (United Kingdom)

For terrestrial animals and plants, a fundamental cost of living is water vapor lost to the atmosphere during exchange of metabolic gases. Here, by bringing together previously developed models for...Full Text Available

2010-05-04

219

Preliminary assessment of condensation behavior for hydrocarbon-vapor expansions which cross the saturation line near the critical point  

Energy Technology Data Exchange (ETDEWEB)

Previous analyses of binary cycles for conversion of geothermal energy from moderate temperature resources to electrical energy have shown potential gains in net geofluid effectiveness on the order of 8%, resulting from selection of turbine-expansion processes whose equilibrium states pass through the two-phase region. If condensation occurs, this gain could be reduced or eliminated by the resulting loss in turbine efficiency. Experience with many fluids, however, indicates that vapor supersaturation permits metastable pure-vapor states to exist at temperatures considerably below the saturation temperature at a given pressure; thus, by better understanding the condensation process, and properly structuring the cycle, substantial performance gains may be possible. The purpose of the present study was to assess the probability for attaining this performance gain by estimating the extent of condensation which might be expected during such an ...

1983-01-01

220

Plasma Treatment within Dielectric Fluids.  

Science.gov (United States)

A dielectric liquid having entrained bubbles of gas or vapor is subjected to an electric field applied between spaced electrodes (112, 116) which generates microdischarges (and thus plasma) within the bubbles, allowing modification of the properties of th...

2003-01-01

221

Oxidation, volatilization, and redistribution of molybdenum from TZM alloy in air  

Energy Technology Data Exchange (ETDEWEB)

The excellent high temperature strength and thermal conductivity of molybdenum-base alloys provide attractive features for components in advanced magnetic and inertial fusion devices. Refractory metal alloys react readily with oxygen and other gases. Oxidized molybdenum in turn is susceptible to losses from volatile molybdenum trioxide species, MoO{sub 3}(m), in air and the hydroxide, MoO{sub 2}(OH){sub 2}, formed from water vapor. Transport of radioactivity by the volatilization, migration, and re-deposition of these volatile species during a potential accident involving a loss of vacuum or inert environment represents a safety issue. In this report the authors present experimental results on the oxidation, volatilization and re-deposition of molybdenum from TZM in flowing air between 400 and 800 C. These results are compared with calculations obtained from a vaporization mass transfer model using chemical thermodynamic data for ...

2000-01-01

222

Oxidation, Volatilization, and Redistribution of Molybdenum from TZM Alloy in Air  

Energy Technology Data Exchange (ETDEWEB)

The excellent high temperature strength and thermal conductivity of molybdenum-base alloys provide attractive features for components in advanced magnetic and inertial fusion devices. Refractory metal alloys react readily with oxygen and other gases. Oxidized molybdenum in turn is susceptible to losses from volatile molybdenum trioxide species, (MoO3)m, in air and the hydroxide, MoO2(OH)2, formed from water vapor. Transport of radioactivity by the volatilization, migration, and re-deposition of these volatile species during a potential accident involving a loss of vacuum or inert environment represents a safety issue. In this report we present experimental results on the oxidation, volatilization and re-deposition of molybdenum from TZM in flowing air between 400 and 800°C. These results are compared with calculations obtained from a vaporization mass transfer model using chemical thermodynamic data for vapor ...

2000-01-01

223

Nomographs for soil vapor extraction and off-gas treatment by activated carbon adsorption  

Energy Technology Data Exchange (ETDEWEB)

Soil vapor extraction (SVE) is a widely accepted in-place treatment technology that uses forced air to remove contaminant vapors from zones of permeable vapor flow, thereby enhancing the volatilization of contaminants from the subsurface. The resulting off-gases are contaminated with volatiles and semi-volatiles and have to treated by catalytic or thermal destruction systems, activated carbon adsorbers, or bioreactors. Of these, activated carbon adsorption is the most commonly used technology. From the theoretical foundation of SVE and carbon adsorption, two nomographs were developed for remedial investigation, feasibility studies, planning, operation, and preliminary design purposes. An advantage of such nomographs is that they graphically indicate the sensitivity of the remediation process to different design parameters and critical ranges within a given parameter. In effect, nomographs can help to foster an intuitive ...

1997-12-31

224

New intelligent monitor for CANDU type NPP  

International Nuclear Information System (INIS)

Nuclear energy provides a third of Europe's electricity with nearly no greenhouse-gas emissions. Sustained efforts are now being conducted to harmonize regulations all over Europe through WENRA and to converge on technical nuclear safety practices within the TSO network ETSON (European Technical Safety Organizations Network). In CANDU type NPP the tritiated water occurs by the neutron bombardment of deuterium. The tritiated water vapors imply health hazard (in the critical organs of the body the water presents a 10 day average biological half-life) and the early detection in nuclear plants of tritium emissions is important because the tritiated water vapors have the same characteristics as of atmospheric water vapors. By detecting tritiated vapors, the monitoring system ensures the following objectives: (a) indicates levels of tritium generally due to heavy water leakage, (b) reduces the possibility of ...

2009-10-12

225

Laboratory Investigation of Steam Adsorption in Geothermal Reservoir Rocks.  

Science.gov (United States)

Some vapor-dominated geothermal reservoirs and low-permeability gas reservoirs exhibit anomalous behavior that may be caused by surface adsorption. For example, geothermal reservoirs in the Larderello area of Italy and reservoirs in the Geysers Geothermal...

1988-01-01

226

Explosives detection The problem and prospects  

Energy Technology Data Exchange (ETDEWEB)

Explosives molecules have a number of unique properties. These properties are discussed. They include low vapor pressures, electronegativity, ''stickiness,'' frangibility, and thermal instability. The program for developing an advanced explosives detector is described.

1984-07-01

227

Determination of vapor-liquid equilibrium data and decontamination factors needed for the development of evaporator technology for use in volume reduction of radioactive waste streams  

Energy Technology Data Exchange (ETDEWEB)

A program is currently in progress at Argonne National Laboratory to evaluate and develop evaporator technology for concentrating radioactive waste streams. By concentrating radioactive waste streams, disposal costs can be significantly reduced. To effectively reduce the volume of waste, the evaporator must achieve high decontamination factors so that the distillate is sufficiently free of radioactive material. One technology that shows a great deal of potential for this application is being developed by LICON, Inc. In this program, Argonne plans to apply LICON`s evaporator designs to the processing of radioactive solutions. Concepts that need to be incorporated into the design of the evaporator include, criticality safety, remote operation and maintenance, and materials of construction. To design an effective process for concentrating waste streams, both solubility and vapor-liquid equilibrium data are needed. The key issue, however, is the high decontamination ...

1993-10-01

228

Designing a healthy house - an overview  

Energy Technology Data Exchange (ETDEWEB)

There are certain factors to take into account when determining the suitability of a healthy house site. Power lines, agricultural spraying, vehicle exhaust, and industrial pollution are all potential sources of indoor air contamination. It is recommended that a environmental assessment be done to determine whether there are specific sources of contamination. Good drainage is required. The surrounding landscaping should be open and sunlit, and with low maintenance requirements. Decks and fences made from pressure-treated or chemical treated lumber should be avoided. One of the early decisions in the design process is the choice of the structural system. The key with all foundation types is to control moisture, whether from rain, from the ground, or the condensation of moisture from the air with cooling. The construction frame is sealed away from the occupants by the air/vapor barrier, so only in extreme cases is it essential to use alternatives to softwood lumber ...

1999-11-01

229

Comparison of Indoor Mercury Vapor in Common Areas of Residential Buildings with Outdoor Levels in a Community Where Mercury Is Used for Cultural Purposes  

UK PubMed Central (United Kingdom)

Elemental mercury has been imbued with magical properties for millennia, and various cultures use elemental mercury in a variety of superstitious and cultural practices, raising health concerns for...Full Text Available

2006-01-01

230

Characterization of MJO ... - Microwave Limb Sounder (MLS) - NASA  

Science.gov (United States)

Feb 15, 2008 ... hydrological properties (e.g., hydrometeor budgets, cloud ice/water, transports ... cloud fraction, mass and particle size. In combination, these .... anomaly in the LS is not simply due isentropic movement of water vapor relative ...

231

4 - NASA Technical Reports Server  

Science.gov (United States)

Mar 1, 2011 ... The movement of hydrothermal fluids and/or fumarolic vapors through local rocks prior ... The Solar Energetic Particle Event of December 14, 2006 .... for measurement of non-precipitating cloud hydrometeors and aerosols, ...

232

Water chemistry in the water-vapor circuit at Angra II: evolution of the operational concepts and canceling of the condensed polishing system; Quimica da agua do circuito agua-vapor de Angra II: evolucao do conceito operacional e o cancelamento do sistema de polimento do condensado  

Energy Technology Data Exchange (ETDEWEB)

The chemical operational concept originally established for the water-steam circuit of Angra II nuclear power plant has undergone several modifications throughout the development of the project. This work discusses the two main modifications giving special attention to the costs involved and analyses the main points and the consequences of such modifications 1 ref., 4 figs., 2 tabs.

1995-12-31

233

Uptake of atmospheric tritium by market foods  

Energy Technology Data Exchange (ETDEWEB)

In this paper uptake of tritium by market foods from tritiated water vapor in the air is investigated using cereals and beans purchased in Deep River, Canada. The concentrations of tissue free water tritium (TFWT) and organically bound tritium (OBT) range from 12 to 79% and from 10 to 38% respectively, of that estimated for atmospheric water vapor of the sampling month. The specific activity ratios of OBT to TFWT were constant for cereals, but variable for beans. The elevated OBT was shown to be the result of isotopic exchange of labile hydrogen by the fact that washing the foods with tritium free-water reduced their tritium contents to levels characteristic of their production sites.

1992-03-01

234

Thermodynamic modeling of acidic gas solubility in aqueous solutions of MEA, MDEA and MEA-MDEA blends  

DEFF Research Database (Denmark)

The thermodynamic framework that was developed in a previous work [Vrachnos et al. Ind. Eng. Chem. Res. 2004, 43, 2798] for the description of chemical and vapor-liquid equilibria of carbon dioxide, hydrogen sulfide, and their mixtures in aqueous methyldiethanolamine (MDEA) solutions is revised and extended in this study to the absorption of carbon dioxide into aqueous monoethanolamine (MEA) solutions and aqueous MDEA-MEA blends. The results of the model are compared with experimental data taken from the literature. Very satisfactory predictions of acidic gas vapor-liquid equilibrium over MDEA, MEA, and their blends at various concentrations, acidic gas loadings, and temperatures are obtained.

2006-01-01

235

The natural convection cooling with vaporizing deuterium for the horizontally arranged cold neutron source of the HFR - Grenoble  

International Nuclear Information System (INIS)

Natural convection of vaporizing Deuterium at 25 K transports the heat generated in the moderator cell of the cold neutron source to a He cooled condenser. The thermohydraulics of this thermosiphon were precalculated and the results verified by experiments in a 1:1 model using D_2 as fluid. The experimental results show that the thermosiphon operates stable. The demanded liquid content of the cell as well as wall temperatures below 50 K can be ensured by a proper design of the cell outlet flow geometry. A 7 min. loss of cryogenic power results in transient temperatures of the cell wall of not more than 300 K.

1991-08-01

236

Production of polarized negative ion beams by collisional pumping  

Energy Technology Data Exchange (ETDEWEB)

The production of polarized negative ion beams by collisional pumping is described. Collisional pumping utilizes repeated charge changing collisions in a thick electron-spin-polarized gas or vapor target to form a polarized fast atom beam. The polarized fast atom beam is then partially converted into a polarized negative ion beam in a vapor target. Analysis is presented for a hydrogen beam passing through either a thick polarized H atom target or a thick polarized alkali target. Large polarizations and large currents may be possible.

1983-01-01

237

Production of polarized negative ion beams by ''collisional pumping''  

Energy Technology Data Exchange (ETDEWEB)

The production of polarized negative ion beams by ''collisional pumping'' is described. Collisional pumping utilizes repeated charge changing collisions in a thick electron-spin-polarized gas or vapor target to form a polarized fast atom beam. The polarized fast atom beam is then partially converted into a polarized negative ion beam in a vapor target. Analysis is presented for a hydrogen beam passing through either a thick polarized H atom target or a thick polarized alkali target. Large polarizations and large currents may be possible.

1984-03-01

238

Plasma production and flow in negative ion beams  

Science.gov (United States)

Plasma generated in low-density vapor by a negative ion beam has been studied experimentally and computationally. We show that space charge neutralization of the beam occurs at very low vapor density, and that correspondingly the electron density may be much less than the beam and plasma ion densities. When there is a large local gas density, as in a charge changing cell, the resulting high electron density is also localized to the same region. Therefore, very few electrons will reach a negative ion accelerator even if it is placed one or two beam diameters from such a cell.

1977-09-21

239

Modeling of (vapor + liquid) equilibrium and enthalpy of solution of carbon dioxide (CO{sub 2}) in aqueous methyldiethanolamine (MDEA) solutions  

Energy Technology Data Exchange (ETDEWEB)

A thermodynamic model was used to estimate enthalpy of solution of carbon dioxide (CO{sub 2}) in methyldiethanolamine (MDEA) aqueous solutions. The model was based on a set of equations for chemical equilibria, phase equilibria, charge, and mass balances. Non-ideality in the liquid phase was taken into account by interaction parameters fitted to (vapor + liquid) equilibrium data. The enthalpies of solution of CO{sub 2} were derived from the model using classical thermodynamic relations and were compared to experimental values obtained in previous works.

2009-06-15

240

Modeling of (vapor + liquid) equilibrium and enthalpy of solution of carbon dioxide (CO_2) in aqueous methyldiethanolamine (MDEA) solutions  

International Nuclear Information System (INIS)

A thermodynamic model was used to estimate enthalpy of solution of carbon dioxide (CO_2) in methyldiethanolamine (MDEA) aqueous solutions. The model was based on a set of equations for chemical equilibria, phase equilibria, charge, and mass balances. Non-ideality in the liquid phase was taken into account by interaction parameters fitted to (vapor + liquid) equilibrium data. The enthalpies of solution of CO_2 were derived from the model using classical thermodynamic relations and were compared to experimental values obtained in previous works.

2009-06-01

241

Mercury vacuum cleaner operational test and evaluation  

Energy Technology Data Exchange (ETDEWEB)

The Dental Investigation Service, USAFSAM, Brooks AFB, has outlined the need for a vacuum unit to be used in the Air Force dental clinics. The unit must be capable of effectively picking up mercury and at the same time not redistribute mercury vapors throughout the dental clinic during normal operations or mercury-spill situations. The Dental Investigation Service selected the MRS-3, Minuteman Mercury Recovery System, product of American Cleaning Equipment Corporation as the mercury vacuum to be used for T E. The USAF OEHL/ECH was requested by the Dental Investigation Service to perform the T E on the MRS-3 for possible health hazards due to exposures of mercury vapors.

1981-03-01

242

Evaluation of tritiated water retention capacity of fusion reactor concrete building  

Energy Technology Data Exchange (ETDEWEB)

In this paper the diffusion of tritiated water vapor into concrete walls is studied to evaluate tritiated water retention capacity of a fusion reactor concrete building. Using a model of the tritiated water diffusion determined form experimental results, depth profiles of tritiated water in concrete are calculated in the case of being exposed to air containing tritiated water vapor during the normal operational condition of a fusion reactor. A 0.5-m-thick concrete is sufficient for reactor hall walls from a viewpoint of the tritium containment.

1992-03-01

243

Evaluation of tritiated water retention capacity of fusion reactor concrete building  

International Nuclear Information System (INIS)

In this paper the diffusion of tritiated water vapor into concrete walls is studied to evaluate tritiated water retention capacity of a fusion reactor concrete building. Using a model of the tritiated water diffusion determined form experimental results, depth profiles of tritiated water in concrete are calculated in the case of being exposed to air containing tritiated water vapor during the normal operational condition of a fusion reactor. A 0.5-m-thick concrete is sufficient for reactor hall walls from a viewpoint of the tritium containment.

244

Use of post-consumer waste plastics in cement-based composites  

Energy Technology Data Exchange (ETDEWEB)

This paper describes an innovative use of post-consumer waste HDPE plastic in concrete as a soft filler. A reference concrete was proportioned to have the 28-day compressive strength of 5000 psi (35 MPa). A high-density plastic was shredded into small particles for use in the concrete. These particles were subjected to three chemical treatments (water, bleach, bleach + NaOH) to improve their bonding with the cementitious matrix. The plastic particles were added to the concrete in the range of 0--5% of total mixture by weight. Compressive strengths were measured for each test mixture. The results showed that chemical treatment has a significant effect on performance of the plastic filler in concrete. Of the three treatments used on the plastic, the best performance was observed with the alkaline bleach treatment (bleach + NaOH) with respect to compressive strength of concrete.

1996-10-01

245

Tracheal compression by mediastinal masses in children: CT evaluation  

Energy Technology Data Exchange (ETDEWEB)

Chest computed tomography (CT) was valuable in detecting extrinsic tracheal compression by mediastinal masses in two pediatric patients. This prompted an independent evaluation by CT of 14 children with masses involving the middle mediastinum and possible intrathoracic tracheal narrowing. Computer programs permit precise calculation of tracheal cross-sectional areas. Any apparent decrease in tracheal area may be compared with CT-derived data in normal children. Chest CT not only demonstrates the presence of extrinsic airway compression in pediatric patients with mediastinal masses, but also is capable of precisely measuring the extent of this narrowing. This method identifies children at potential risk for respiratory compromise and may aid in subsequent therapy.

1983-10-01

246

Trabecular scaffolds created using micro CT guided fused deposition modeling  

British Library Electronic Table of Contents (United Kingdom)

Free form fabrication and high resolution imaging techniques enable the creation of biomimetic tissue engineering scaffolds. A 3D CAD model of canine trabecular bone was produced via micro CT and exported to a fused deposition modeler, to produce polybutylene terephthalate (PBT) trabeculated scaffolds and four other scaffold groups of varying pore structures. The five scaffold groups were divided into subgroups (n=6) and compression tested at two load rates (49?N/s and 294?N/s). Two groups were soaked in a 25??C saline solution for 7?days before compression testing. Micro CT was used to compare porosity, connectivity density, and trabecular separation of each scaffold type to a canine trabecular bone sample. At 49?N/s the dry trabecular scaffolds had a compressive stiffness of 4.94?1.19?MP...

2008-01-01

247

Three dimensional simulation of compressible and incompressible flows through the finite element method; Simulacao tridimensional de escoamentos compressiveis e incompressiveis atraves do metodo dos elementos finitos  

Energy Technology Data Exchange (ETDEWEB)

Although incompressible fluid flows can be regarded as a particular case of a general problem, numerical methods and the mathematical formulation aimed to solve compressible and incompressible flows have their own peculiarities, in such a way, that it is generally not possible to attain both regimes with a single approach. In this work, we start from a typically compressible formulation, slightly modified to make use of pressure variables and, through augmenting the stabilising parameters, we end up with a simplified model which is able to deal with a wide range of flow regimes, from supersonic to low speed gas flows. The resulting methodology is flexible enough to allow for the simulation of liquid flows as well. Examples using conservative and pressure variables are shown and the results are compared to those published in the literature, in order to validate the method. (author)

2004-11-15

248

Thermomechanical Behavior of Ceramic Green Bodies During Presintering  

British Library Electronic Table of Contents (United Kingdom)

A testing methodology, which includes the evaluation of free sintering strain, stress-induced dimensional changes, and weight changes, was developed to determine the critical dimensional changes and thermomechanical response during presintering (i.e., before densification). The effects of organic binder burnout, decomposition of phases, and phase changes on the thermomechanical behavior of a ceramic green body, consisting of methylcellulose as a binder, gibbsite, silica, and alumina, were studied. The compressive stress-strain behavior was found to be nonlinear. The average compressive and tensile strengths of the sample at room temperature were -14.5 and 1.06 MPa, respectively. Both the compressive and tensile strengths decrease by two orders of magnitude with the increasing temperature a...

2010-01-01

249

The deformation behavior of DyCu ductile intermetallic compound under compression  

British Library Electronic Table of Contents (United Kingdom)

In this study polycrystalline specimens of as-cast DyCu with B2 crystal structure were compressed to different strains at room temperature to test if stress-induced phase transformation and twinning occur during deformation. In these tests DyCu exhibited high ductility with plastic strain as high as 35% and ultimate compressive strength of ~790MPa. X-ray diffraction and transmission electron microscopy (TEM) showed no indications that DyCu had undergone stress-induced phase transformation or twinning. -type dislocations have been observed to play an important role for imparting the ductile behavior. TEM analyses showed the presence of second phases, Dy2O3 and DyCu2 within the DyCu. The mechanisms of ductility and impurity phase formation are discussed.

2011-01-01

250

The bone mineral content and ultimate compressive strength of lumbar vertebrae.  

Science.gov (United States)

The bone mineral content of 109 lumbar vertebrae from 36 different subjects was determined by dual photon absorptiometry. The mean age of the subjects was 58.5 years (range, 31 to 79 years). The ultimate strength of the vertebral bodies was determined during axial compression. Bone mineral content and ultimate compressive strength were correlated (r = 0.86) and the strength was found to increase linearly with increasing amounts of bone mineral content. No differences in this correlation were found in the four vertebral levels (L-4) included in the study, but a difference in this correlation was found between specimens taken from male and female subjects. The results make it possible to estimate the strength of a vertebral body from the knowledge of its bone mineral content as determined by dual photon absorptiometry and provide a basis of estimations of normal and abnormal amounts of bone mineral content in the vertebrae of the lumbar spine. ...

251

Numerical and semi-analytic core mass distributions in supersonic isothermal turbulence  

CERN Document Server

We investigate the influence of the turbulence forcing on the mass distributions of gravitationally unstable cores by postprocessing data from simulations of non-selfgravitating isothermal supersonic turbulence with varying resolution. In one set of simulations solenoidal forcing is applied, while the second set uses purely compressive forcing to excite turbulent motions. From the resulting density field, we compute the mass distribution of gravitationally unstable cores by means of a clump-finding algorithm. Using the time-averaged probability density functions of the mass density, semi-analytic mass distributions are calculated from analytical theories. We apply stability criteria that are based on the Bonnor-Ebert mass resulting from the thermal pressure and from the sum of thermal and turbulent pressure. Although there are uncertainties in the application of the clump-finding algorithm, we find systematic differences in the mass distributions obtained from ...

2010-01-01

252

Mechanical deformation and tensile super-elastic behaviors of a Ti-Mo based shape memory alloy  

Science.gov (United States)

Ni-free shape memory alloys are promising functional materials for medical applications. A newly developed Ti-Mo based shape memory alloy shows superelasticity after thermomechanical treatment. However, the microstructure evolution and precipitation during thermomechanical processes are still not well understood. In the present paper, compressive deformation behavior at a series of temperatures of 298K - 973K and tensile deformation behavior of the alloy after aged at 573K - 973K have been investigated systematically. It is found that the compressive yield stress and ultimate compressive strength change with the deformation temperature. The ultimate tensile strength and yield stress of aged specimens also change with the aging temperature following a non-linear relationship. Microstructures of aged specimens as well as effects of lattice softening and aging-induced precipitates on the deformation behavior have been ...

2011-03-01

253

Facesheet debonding criteria for composite sandwich panels under in-plane compression  

Science.gov (United States)

A method for determining the critical debond size between the facesheet and the core in composite sandwich panels under in-plane compression is described. The approach uses fracture mechanics together with a buckling criterion for a debonded faceskin. The technique yields predictions for the critical in-plane compressive load for debond propagation as a function of core-to-faceskin debond size, faceskin thickness, lay-up, composite material properties, and honeycomb properties and geometry. A computer program, developed in this work, calculates the critical buckling load and facesheet deformed shape by solving an eigenvalue problem. The output predicts, for several cases, critical initial debond lengths comparable to those that have been observed on tests on sandwich panels.

1992-07-01

254

Combustion characteristics of compressed natural gas/diesel dual-fuel turbocharged compressed ignition engine  

Energy Technology Data Exchange (ETDEWEB)

The combustion characteristics of a turbocharged natural gas and diesel dual-fuelled compression ignition (CI) engine are investigated. With the measured cylinder pressures of the engine operated on pure diesel and dual fuel, the ignition delay, effects of pilot diesel and engine load on combustion characteristics are analysed. Emissions of HC, CO, NO{sub x} and smoke are measured and studied too. The results show that the quantity of pilot diesel has important effects on the performance and emissions of a dual-fuel engine at low-load operating conditions. Ignition delay varies with the concentration of natural gas. Smoke is much lower for the developed dual-fuel engine under all the operating conditions. (Author)

2003-09-01

255

Burner systems  

Energy Technology Data Exchange (ETDEWEB)

A burner system particularly useful for downhole deployment includes a tubular combustion chamber unit housed within a tubular coolant jacket assembly. The combustion chamber unit includes a monolithic tube of refractory material whose inner surface defines the combustion zone. A metal reinforcing sleeve surrounds and extends the length of the refractory tube. The inner surface of the coolant jacket assembly and outer surface of the combustion chamber unit are dimensioned so that those surfaces are close to one another in standby condition so that the combustion chamber unit has limited freedom to expand with that expansion being stabilized by the coolant jacket assembly so that compression forces in the refractory tube do not exceed about one-half the safe compressive stress of the material; and the materials of the combustion chamber unit are selected to establish thermal gradient parameters across the combustion chamber unit to maintain the ...

1984-07-10

256

An experimental study on the tensile strength of steel fiber reinforced concrete  

British Library Electronic Table of Contents (United Kingdom)

This paper deals with steel fiber reinforced concrete mechanical static behaviour and with its classification with respect to fibers content and mix-design variations. A number of experimental tests were conducted to investigate uniaxial compressive strength and tensile strength. Different mixtures were prepared varying both mix-design and fiber length. Fibers content in volume was of 1% and 2%. Mechanical characterization was performed by means of uniaxial compression tests with the aim of deriving the ultimate compressive strength of fiber concrete. Four-point bending tests on notched specimens were carried out to derive the first crack strength and the ductility indexes. The tensile strength of steel fiber reinforced concrete (SFRC) was obtained both from an experimental procedure and b...

2010-01-01

257

Theory of multifoil collision supercompression  

Energy Technology Data Exchange (ETDEWEB)

Investigations of superdense compression touch on such problems as ultrahigh-frequency oscillations of matter in the generation of gravitational waves, the powerful pumping of hard coherent radiation, and the laboratory simulation of stellar interiors. This paper reviews the theory of supercompression and discusses some experiments involving multifoil collision supercompression.

1980-01-01

258

Stress-assisted crystallisation in anodic titania  

International Nuclear Information System (INIS)

Research highlights: ? Correlations between microstructure and internal stress during Ti anodising are established. ? Large internal compressive stresses are accumulated in the film during anodising upto 12 V. ?A transition from compressive to tensile stress is observed when the cell voltage exceeds 12 V. ? At 40 V, the oxide films consist of two regions with different compositions and microstructures. Crystallisation of amorphous to anatase TiO2 contributes to the compressive stress relaxation. - Abstract: The relationship between the microstructural and internal stress evolution during Ti anodising is discussed. Samples anodised galvanostatically to 12 V and 40 V, corresponding to different stages of the internal stress evolution, were examined by in-plane and cross-section transmission electron microscopy. Electron diffraction patterns have been complemented with stoichiometry data obtained from energy loss near edge ...

2011-04-01

259

Spontaneous cervical epidural hematoma: Report of a case managed conservatively  

UK PubMed Central (United Kingdom)

Spontaneous spinal epidural hematoma is a rare cause of acute spinal cord compression. A 25-year-old male presented with a history of sudden onset of complete quadriplegia with sensory loss below the...Full Text Available

2008-07-01

260

Selected Physical and Chemical Properties of Feverfew (Tanacetum parthenium) Extracts Important for Formulated Product Quality and Performance  

UK PubMed Central (United Kingdom)

The objectives of this research are: (1) to assess selected formulation-relevant physical properties of several commercial Feverfew extracts, including flowability, hygroscopicity, compressibility and...Full Text Available

261

Pulse compression in a free electron laser amplifier  

International Nuclear Information System (INIS)

We have studied both theoretically and experimentally a new scheme of active pulse compression in a free electron laser (FEL) amplifier. The pulse compression scheme presented here is the following. A frequency-chirped pulse is injected into the FEL interaction region. Because of the high gain and narrow bandwidth of the FEL interaction, only the resonant frequency band of the pulse is actively amplified, resulting in a short pulse of high power coherent radiation at the output of the laser. For our experimental parameters (beam voltage #approx =# 150 kV, current #approx =# 5.0 A, wiggler period #approx =# 3.5 cm and gain #approx =# 10 dB), pulses of a few nanoseconds were generated at #approx =# 10 GHz after an interaction length of 2.30 m, in good agreement with theoretical expectations. For the same input pulses (width > 100 ns, frequency chirp #alpha#/2#pi# #approx =# 5 MHz/ns), the obtention of such compression ...

262

Plantago ovata Mucilage in the Design of Fast Disintegrating Tablets  

UK PubMed Central (United Kingdom)

In the present work, fast disintegrating tablets of prochlorperazine maleate were designed with a view to enhance patient compliance by direct compression method. In this method mucilage of Plantago...Full Text Available

2009-01-01

263

On-line plasticity in spoken sentence comprehension: Adapting to time-compressed speech  

UK PubMed Central (United Kingdom)

AbstractListeners show remarkable flexibility in processing variation in speech signal. One striking example is the ease with which they adapt to novel speech distortions such as listening...Full Text Available

2010-01-01

264

Nonlinear transmission of two successive ultrashort laser pulses by a thin semiconductor film under two-photon generation of biexcitons. Giant oscillator strength model  

International Nuclear Information System (INIS)

The possibility to compress and to split laser pulses at their nonlinear optical transmission through semiconductor films was investigated

2011-07-07

265

MRI features of epidural extramedullary hematopoiesis  

Energy Technology Data Exchange (ETDEWEB)

A case of {beta}-thalassemia intermedia with spinal cord compression due to extramedullary hematopoiesis, which was successfully treated by blood transfusion, is presented. Emphasis was made on the MRI appearance of extramedullary hematopoiesis on different pulse sequences. The theories that aimed to explain the involvement of the epidural space by extramedullary hematopoiesis are discussed.

2000-07-01

266

Foraminal stenosis complicating retained broken epidural needle tip -A case report-  

UK PubMed Central (United Kingdom)

Lumbar epidural anesthesia is useful in a variety of chronic benign pain syndromes, including lumbar radiculopathy, low back pain syndrome, spinal stenosis, and vertebral compression fractures. Given...Full Text Available

2010-12-01

267

ELECTRONIC COMPONENT COOLING ALTERNATIVES: COMPRESSED AIR AND LIQUID NITROGEN  

Science.gov (United States)

The goal of this study was to evaluate topics used to troubleshoot circuit boards with known or suspected thermally intermittent components. Failure modes for thermally intermittent components are typically mechanical defects, such as cracks in solder paths or joints, or broken b...

268

Dynamic and Static Tests of Plain Concrete Specimens ...  

Science.gov (United States)

... 4.4+9 4.30 ds~ ;'* Page 24. Table 3 Ultimate Compressive Strength Data Static Dynamic Round Strength Range Strength Range No. Avg Rise 0No. ...

1963-11-01

269

Development of compressed natural gas/diesel dual-fuel turbocharged compressed ignition engine  

Energy Technology Data Exchange (ETDEWEB)

A natural gas and diesel dual-fuel turbocharged compression ignition (CI) engine is developed to reduce emissions of a heavy-duty diesel engine. The compressed natural gas (CNG) pressure regulator is specially designed to feed back the boost pressure to simplify the fuel metering system. The natural gas bypass improves the engine response to acceleration. The modes of diesel injection are set according to the engine operating conditions. The application of honeycomb mixers changes the flowrate shape of natural gas and reduces hydrocarbon (HC) emission under low-load and lowspeed conditions. The cylinder pressures of a CI engine fuelled with diesel and dual fuel are analysed. The introduction of natural gas makes the ignition delay change with engine load. Under the same operating conditions, the emissions of smoke and NO{sub x} from the dual-fuel engine are both reduced. The HC and CO emissions for the dual-fuel engine remain within the range ...

2003-09-01

270

DIFFERENCES IN THE MECHANICAL BEHAVIOR OF CORTICAL BONE BETWEEN COMPRESSION AND TENSION WHEN SUBJECTED TO PROGRESSIVE LOADING  

UK PubMed Central (United Kingdom)

The hierarchical arrangement of collagen and mineral into bone tissue presumabley maximizes fracture resistance with respect to the predominant strain mode in bone. Thus, the ability of cortical...Full Text Available

2009-12-01

271

Combining hot-compressed water and ball milling pretreatments to improve the efficiency of the enzymatic hydrolysis of eucalyptus  

UK PubMed Central (United Kingdom)

BackgroundLignocellulosic biomass such as wood is an attractive material for fuel ethanol production. Pretreatment technologies that increase the digestibility of cellulose and hemicellulose...Full Text Available

272

Cement-based composites: Strain rate effects on fracture  

Energy Technology Data Exchange (ETDEWEB)

This book contains over 20 selections. Some of the titles are: Continuum damage mechanics studies on the dynamic fracture of concrete; Dynamic compressive strength of cementitious materials; Rate-sensitivity of mode I and mode II fracture concrete; and An impact damage model of concrete.

1986-01-01

273

CPR - infant - series (image)  

Science.gov (United States)

... yourself to call 911 until you have performed CPR for about 2 minutes. 3. Carefully place the ... more breaths. The chest should rise. 9. Continue CPR (30 chest compressions followed by 2 breaths, then ...

274

CPR - child 1 to 8 years old - series (image)  

Science.gov (United States)

... and retrieve an AED until you have performed CPR for about 2 minutes. 3. Carefully place the ... more breaths. The chest should rise. 9. Continue CPR (30 chest compressions followed by 2 breaths, then ...

275

The amount of bone mineral and Schmorl's nodes in lumbar vertebrae.  

Science.gov (United States)

The bone mineral areal content and the ultimate compressive strength were determined in 109 lumbar vertebrae from 36 subjects. The bone mineral areal content was related to the number, shape, and localization of the Schmorl's nodes detected in the x-rayed and sectioned vertebral bodies. One type of node, irregular in shape and localization, occurred only in the vertebrae with low bone mineral areal content values and thus in vertebrae with relatively low compressive strength. A second type of Schmorl's nodes, regular in shape and localization, did not reflect any general weakness of the vertebral bodies. PMID:6623194

1983-04-01

276

Structural, Vibrational and Mechanical Studies of Hydroxyapatite produced by wet-chemical methods  

CERN Document Server

Hydroxyapatite samples were produced by two different wet-chemical methods, and characterized by x-ray diffraction, infrared and compression strength measurements. The x-ray diffraction measurements were simulated using the Rietveld method, and structural data as lattice parameters and average crystallite size were obtained. The infrared spectra showed the presence of CO$_3^{2-}$ ions in all samples, indicating a contamination by these ions. By mixing samples produced by both methods, a bioceramic was obtained and, after sintering, samples with very high compression strengths (26--30 MPa) were obtained.

2004-01-01

277

On Phase Transition of Compressed Sensing in the Complex Domain  

CERN Document Server

The phase transition is a performance measure of the sparsity-undersampling tradeoff in compressed sensing (CS). This letter reports, for the first time, the existence of an exact phase transition for the $\\ell_1$ minimization approach to the complex valued CS problem. This discovery is not only a complementary result to the known phase transition of the real valued CS but also shows considerable superiority of the phase transition of complex valued CS over that of the real valued CS. The results are obtained by extending the recently developed ONE-L1 algorithms to complex valued CS and applying their optimal and iterative solutions to empirically evaluate the phase transition.

2011-01-01

278

Microstructure, texture and mechanical properties of the magnesium alloy AZ31 processed by ECAP  

Energy Technology Data Exchange (ETDEWEB)

To investigate the influence of equal channel angular pressing on the microstructure and texture of the magnesium alloy AZ31, electron backscattering diffraction and well as neutron diffraction experiments were carried out. Through these experiments it was possible to trace the microstructure and texture evolution with strain accumulated with the increasing number of equal channel angular pressing passes. It was further demonstrated by subsequent compression tests that the microstructural changes produced by equal channel angular pressing have a beneficial effect on both the compressive strength and ductility of AZ31. (orig.)

2008-01-15

279

Method for syndrome coding and its application to fast hardware data selection based on the processors operating in the GF(2sup(m)) Galois field  

International Nuclear Information System (INIS)

The method of syndrome coding for data compression read out from multiwire proportional chambers that has been previously proposed is generalized in case of its application to registration of the coordinates of events detected. The questions of execution of arithmetic and algebraic operations on the Galois field elements and their hardware implementation are considered. The method of computation is presented of a specialized processor for parallel computing the coordinates of three sparks. The estimate of its speed is equal to 185 ns. Data compression, data selection and coordinate calculations are performed without use of memory elements and timing pulses.

280

Method and apparatus for operation of a dual fuel compression ignition combustion engine  

Energy Technology Data Exchange (ETDEWEB)

A dual fuel engine control system for controlling the power output of a dual fuel compression ignition engine. The engine includes mixing means for combining an oxidizer and a primary fuel at a substantially constant ratio of oxidizer to primary fuel. The power output of the engine is controlled through the use of a throttle valve controlling the quantity of combustible mixture delivered to the combustion chamber. The fuel control system minimizes the quantity of ignition fuel required by controlling the quantity of combustible mixture rather than the fuel of air ratio. (author) figs.

1994-03-03

281

Low emissions compression ignited engine technology  

Energy Technology Data Exchange (ETDEWEB)

A method and apparatus for operating a compression ignition engine having a cylinder wall, a piston, and a head defining a combustion chamber. The method and apparatus includes delivering fuel substantially uniformly into the combustion chamber, the fuel being dispersed throughout the combustion chamber and spaced from the cylinder wall, delivering an oxidant into the combustion chamber sufficient to support combustion at a first predetermined combustion duration, and delivering a diluent into the combustion chamber sufficient to change the first predetermined combustion duration to a second predetermined combustion duration different from the first predetermined combustion duration.

2007-04-03

282

Ignition delay in the dual fuel engine  

Energy Technology Data Exchange (ETDEWEB)

Tests have been conducted on a special compression ignition research engine to investigate the effects of gaseous fuels on the ignition delay in dual fuel engines. Diesel oil, n-heptane, or cetane were used as pilot fuels, and hydrogen, carbon monoxide, or methane were inducted in the intake manifold. Induction of nitrogen was used as a reference to eliminate the influence of changes in oxygen concentration and specific heats. Helium was inducted in additional tests. From the results of a number of parameter variations, the cylinder charge temperature (determined by intake temperature and compression ratio), the pilot fuel amount, and the flow of combustible gas were found to have the most significant influence on the ignition delay.

1987-01-01

283

Experimental and theoretical analysis of compression ratio on Otto-cycle engines. Pt. 1  

Energy Technology Data Exchange (ETDEWEB)

The increase of the compression ratio of Otto carburator engines up to epsilon = 14 was investigated by Audi in its research department at Neckarsulm. The results are presented in three partial reports. Part one describes the Audi fuel method and demonstrates the effects of the main parameters. Part two shows the influence of the current on the combustion by the help of a new measuring method developed by the Institut fuer Physikalische Elektronik at Stuttgart University. Part three provides a theoretical analysis of the data gained in the investigations.

1982-01-01

284

Compressed hydrogen fuelled vehicles: reasons of a choice and developments in ENEA  

Energy Technology Data Exchange (ETDEWEB)

Some recent achievements in the field of high pressure vessels and safety devices have offered a concrete chance to the application of compressed hydrogen for fleet commercial vehicles for urban use. Accordingly with this concept, ENEA has modified a Fiat Ducato van with a dual fuel engine, retaining the gasoline tank for long distance travelling and adopting the external mixture formation technique, with hydrogen injectors developed by ENEA, for non-polluting short-range duties in urban traffic. The article deals with the rationale for this choice and gives a general view of the project. (author)

1996-12-01

285

A micro-compression study of shape-memory deformation in U-13at%Nb  

Energy Technology Data Exchange (ETDEWEB)

Micro-compression specimens, 1O-15{mu}m in diameter by 20-30{mu}m in height, were produced from individual parent grains in a polycrystalline U-13at%Nb shape-memory alloy using the focused ion beam (FIB) technique. The specimens were tested in a nanoindentation instrument with a flat diamond tip to investigate stress-strain behavior as a function of crystallographic orientation. The results are in qualitative agreement with a single-crystal accommodation strain (Bain strain) model of the shape-memory effect for this alloy.

2008-01-01

286

Venus surface power and cooling systems  

British Library Electronic Table of Contents (United Kingdom)

A mission to the surface of Venus would have high scientific value, but most electronic devices and sensors cannot operate at the 450degreeC ambient surface temperature of Venus. Power and cooling systems were analyzed for Venus surface operation. A radioisotope power and cooling system was designed to provide electrical power for a probe operating on the surface of Venus. For a mission duration of substantial length, the use of thermal mass to maintain an operable temperature range is likely impractical, and active refrigeration may be required to keep components at a temperature below ambient. Due to the high thermal convection of the high-density atmosphere, the heat rejection temperature was assumed to be at a 500degreeC radiator temperature, 50degreeC above ambient. The radioisotope S...

2007-01-01

287

Twenty Years of Tevatron Operation  

Energy Technology Data Exchange (ETDEWEB)

The superconducting Tevatron accelerator at Fermi National Accelerator Laboratory (Fermilab) has surpassed twenty years of operation. The Tevatron is still the highest energy particle accelerator in the world and will remain so until the commissioning of the LHC in Europe later this decade. The Tevatron has operated in a Fixed Target mode, accelerating a proton beam into stationary targets/detectors, as well as a Colliding Beam mode, continuously colliding counter rotating beams of protons and antiprotons. Upon completion, the Tevatron cryogenic system became the world's largest helium refrigeration system. In 1993, the Tevatron cryogenic system was given the designation of International Historic Mechanical Engineering Landmark by the American Society of Mechanical Engineers. The operational history, experiences and statistics of the Tevatron, with an emphasis on the cryogenic system, is presented. Improvements, upgrades and current challenges of the ...

2004-07-15

288

The Micro-X Imaging Spectrometer Instrument  

Science.gov (United States)

The Micro-X instrument is a NASA funded, rocket borne X-ray imaging spectrometer planned for launch in January 2011. An array of Transition Edge Sensors (TESs) will observe incoming photons in the 0.2-3 keV energy band with an energy resolution of 2-4 eV at 1 keV. This will be a substantial improvement over current non-dispersive detectors for X-ray spectroscopy of extended sources and will be the first demonstration of a TES-based microcalorimeter in space. The TESs will utilize the 50 mK stage of an Adiabatic Demagnetization Refrigerator (ADR) as a heat sink, and will be read out by a SQUID time division multiplexer. X-rays will be focused onto the TES array of 128 pixels on a 600 micron pitch by a conically approximated Wolter optic with an effective area of 200 cm2. The spectrometer will have a field of view of 11.8 arcmin. We describe the design and development progress of the instrument.

2010-01-01

289

Post-CHF heat transfer with water and refrigerants  

Energy Technology Data Exchange (ETDEWEB)

Heat transfer experiments were performed in the post-CHF two-phase flow regime in a vertical tube. The tube inside diameter was 7.75 mm, and the boiling fluid was R-113. The experiments were performed at steady state by means of liquid heating of the test tube. Wall superheats were maintained below 70 C for heat exchanger/steam generator application. The mass flux range of the data was 379-816 kg m{sup -2} s{sup -1}. The use of R-113 significantly extended the property range of the existing low wall-superheat data base. Experimental data are presented in tabular as well as graphical form, and the results were used with low wall-superheat data from other fluids to add generality to a predictive heat transfer correlation. (orig.)

1996-06-01

290

Part I: Experimental investigation of the boiling of binary mixtures of Freon-11 and refrigeration lube oils  

Energy Technology Data Exchange (ETDEWEB)

Several experimental runs have been carried out to study nucleate boiling of binary mixtures consisting of Freon-11 and lube oils such as SUNISO 3GS and 4GS in oil concentrations ranging from 0 to 24% by volume. The effect of the heating source temperature on the rate of boiling at various pressures has been studied and the boiling curves at different oil concentrations and pressures have been investigated at an excess temperature of up to 80/sup 0/C. The experimental data have been used to find the effect of pressure, oil concentration and excess temperature on the boiling heat transfer coefficient. The P-T relations for both kinds of mixtures have been measured at different oil concentrations. The heat lost to the atmosphere have also been studied as a function of oil concentration for both kinds of mixtures.

1986-01-01

291

Modelling and simulation of a solar cooler based on physical adsorption; Modelagem e simulacao de um refrigerador solar por adsorcao fisica  

Energy Technology Data Exchange (ETDEWEB)

This study describes the construction of a simple mathematical model its validation through the simulation in transient state of a real cycle performed by a solar refrigerator based on physical adsorption using an activated carbon/methanol pair. The deviation from experimental results was 4% for the cycled mass of methanol, 2.2 % for maximum collector average temperature, and 3 x 10{sup -3} for the theoretical cycle coefficient of performance. Additional simulations of the same cycle inputting values representing different types and larger amounts of activated carbon showed the possibility of increasing the cycled methanol mass up to about 150%. (author) 26 refs., 16 figs., 9 tabs.

1993-12-31

292

Experimental assessment of energy storage via variable speed compressor  

British Library Electronic Table of Contents (United Kingdom)

In this study, usage of a variable speed refrigeration system in latent heat thermal energy storage (LHTES) system is investigated to increase energy storage efficiency. Four different compressor speed control cases are compared to obtain a constant heat transfer fluid (HTF) temperature at the inlet of the energy storage tank. These control cases are (i) control with evaporation temperature, (ii) control with ethylene glycol temperature at the outlet section of evaporator, (iii) control with suction pressure of the compressor and (iv) on/off control. By means of the experimental analysis the best control strategy is obtained as control with Case (ii), in terms of stability of inlet temperature of heat transfer fluid, variations of energy efficiency of LHTES and coefficient of performance (...

2011-01-01

293

Economic thickness for industrial insulation  

Energy Technology Data Exchange (ETDEWEB)

This manual is presented in 8 chapters plus appendices. Chapters 1 and 2 are included as background information. The economic insulation thickness is found using the following chapters: Chapter 3, cost of energy (heat and refrigeration); Chapter 4, cost of insulation, and Chapter 5, economic thickness determination. Each of these chapters contains a worksheet, which provides a step-by-step procedure for solving the problem. Nomographs are included in each section for simplifying the required calculations. For subambient temperature systems, the economic insulation thickness calculated with Chapters 3 to 5 should be compared to the thickness required to prevent condensation (sweating), as calculated with Chapter 6. Chapter 7 presents the procedure for calculating economic insulation for retrofit situations. Sample problems are included in Chapter 8.

1983-01-01

294

Comparison of media and methods for detecting and enumerating Listeria monocytogenes in refrigerated cabbage.  

Science.gov (United States)

Direct plating, selective enrichment, and cold enrichment followed by secondary selective enrichment procedures were compared for detecting and enumerating Listeria monocytogenes in chopped cabbage stored at 5 degrees C for up to 64 days. Addition of Fe3+ to solid media enhanced detection of the organism. Cold enrichment (5 degrees C) in nutrient broth and brain heart infusion broth followed by secondary enrichment (48 h, 30 degrees C) in Trypticase soy-yeast extract-antibiotic broth and thiocyanate-nalidixic acid broth and plating on selective agar media (Doyle and Schoeni selective enrichment agar [minus acriflavin hydrochloride, supplemented with 5 micrograms of Fe3+/ml] and McBride Listeria agar) resulted in the detection of highest populations. PMID:3111369

1987-05-01

295

Air conditioning in high rise buildings; Conditionnement d'air dans les immeubles de grande hauteur  

Energy Technology Data Exchange (ETDEWEB)

This two-tomes book brings together the 108 presentations given at the first conference of the international institute of refrigeration (IIF/IIR) about air conditioning in high rise office buildings. The main themes are: general design and control systems, including split systems, radiant panels, fluctuating and gravity ventilation etc..; energy consumption, optimization and heat recovery; cold storage for peak shaving, including ice slurry circulation; indoor air quality; fire and smokes protection, protection against chimney effects and lighting spots; use of fuzzy logic and of neural networks. It includes also a description of the high rise building situation and works in progress in China, Japan and in some other countries. (J.S.)

1997-07-01

296

Aerogels: the leading edge in thermal insulation  

Energy Technology Data Exchange (ETDEWEB)

Banning CFCs in foamed insulations has led to an intensive search for alternatives which do not incur the penalty of increased thickness. The most promising of these are silica aerogels, which have proven to be the leading material, when it comes to thermal insulation and environmental protection. Refrigerators insulated with aerogels have been tested and compared to conventionally insulated ones. Results showed a substantial contribution to the energy performance. Boiler manufacturers using aerogel have been able to reduce energy consumption of water heaters by 20%. Float glass elements evacuated and filled with aerogel as well as aerogel insulated polyester lightwalls and bubble skylights yield excellent U-values and significantly reduced energy losses in buildings. (author)

1995-01-01

297

A Versatile Evaporative Cooling System Designed for Use in an Elementary Particle Detector  

British Library Electronic Table of Contents (United Kingdom)

An evaporative cooling system developed for operation and qualification testing of silicon pixel and microstrip detectors for the inner tracking detector of the CERN ATLAS spectrometer is described. Silicon detector substrates must be continuously operated between 0 and ???7?C in the high radiation environment near the circulating beams at the CERN Large Hadron Collider (LHC). This requirement imposes unusual constraints on the cooling system and has led to the choice of perfluoro-n-propane (C3F8) refrigerant, which combines good chemical stability under ionizing radiation with high dielectric strength and nonflammability. Since the silicon detectors must also be of extremely light construction to minimize undesirable physics background, coolant tubes are of thin (200 ?m) aluminum wall, wh...

2007-01-01

298

Ranking Hearing Aid Input-Output Functions for Understanding Low-, Conversational-, and High-Level Speech in Multitalker Babble  

Science.gov (United States)

Purpose: To determine the rankings of 6 input-output functions for understanding low-level, conversational, and high-level speech in multitalker babble without manipulating volume control for listeners with normal hearing, flat sensorineural hearing loss, and mildly sloping sensorineural hearing loss. Method: Peak clipping, compression limiting, and 4 wide dynamic range compression (WDRC) input-output functions were compared in a repeated-measure design. Interactions among the compression characteristics were minimized. Speech and babble were processed and recorded at 3 input levels: 45, 65, and 90 dB sound pressure level. Speech recognition of 3 groups of listeners (n = 6/group) was tested for speech processed by each input-output function and at each input level. Results: Input-output functions that made low-level speech audible and high-level speech less distorted by avoiding peak clipping or severe ...

2007-04-01

299

PROGRESS IN BEAM FOCUSING AND COMPRESSION FOR WARM-DENSE MATTER EXPERIMENTS  

Energy Technology Data Exchange (ETDEWEB)

The Heavy-Ion Fusion Sciences Virtual National Laboratory is pursuing an approach to target heating experiments in the Warm Dense Matter regime, using spacecharge-dominated ion beams that are simultaneously longitudinally bunched and transversely focused. Longitudinal beam compression by large factors has beendemonstrated in the Neutralized Drift Compression Experiment (NDCX) with controlledramps and forced neutralization. Using an injected 30-mA K+ ion beam with initialkinetic energy 0.3 MeV, axial compression leading to ~;;50-fold current amplification andsimultaneous radial focusing to beam radii of a few mm have led to encouraging energy deposition approaching the intensities required for eV-range target heating experiments. We discuss the status of several improvements to our Neutralized Drift Compression Experiment and associated beam diagnostics that are under development to reach the necessary ...

2008-09-25

300

Multi-Resolution Modeling of Large Scale Scientific Simulation Data  

Energy Technology Data Exchange (ETDEWEB)

Data produced by large scale scientific simulations, experiments, and observations can easily reach tera-bytes in size. The ability to examine data-sets of this magnitude, even in moderate detail, is problematic at best. Generally this scientific data consists of multivariate field quantities with complex inter-variable correlations and spatial-temporal structure. To provide scientists and engineers with the ability to explore and analyze such data sets we are using a twofold approach. First, we model the data with the objective of creating a compressed yet manageable representation. Second, with that compressed representation, we provide the user with the ability to query the resulting approximation to obtain approximate yet sufficient answers; a process called adhoc querying. This paper is concerned with a wavelet modeling technique that seeks to capture the important physical characteristics of the target scientific data. Our approach is ...

2002-02-25

301

Investigation of the effect of laundering the ground crew chemical defense overgarment on toxic-free-area vapor transfer during shelter entry by initially contaminated personnel. Interim report, Oct 87-Jan 88  

Energy Technology Data Exchange (ETDEWEB)

A study by the U.S. Air Force School of Aerospace Medicine, Brooks AFB, Texas, has compared the shelter processing transfer of chemical warfare agent simulant vapor for subjects wearing unwashed and laundered ground-crew chemical defense overgarments. Twice laundered and four times laundered protective garments were included in the assessment. Test subjects, wearing the unwashed and laundered protective garments were initially sprayed with liquid simulant (methyl salicylate) to a target density of 5 g m-2. They were then sequentially processed into and through the USAFSAM Collective Protection Shelter (SCPS-2B) test facility. Immediately upon entry to the Toxic-Free Area, the subjects were confined in individual off gassing booths for 2 h while offgassed simulant vapor concentration in the booths was recorded. The resulting mean maximum vapor concentrations recorded in the booths for subjects who had worn unwashed and ...

1990-12-01

302

Two-phase flow patterns and frictional pressure gradients in a small, horizontal, rectangular channel  

Energy Technology Data Exchange (ETDEWEB)

Two-phase flow patterns and frictional pressure gradients in flow in small, rectangular channels are being studies as part of a larger research program addressing phase-change heat transfer of pure refrigerants and refrigerant mixtures in plate-fin heat exchangers. Small rectangular flow channels were selected as representative of plain fin geometries. The particular channel reported herein has dimensions of 19.05 {times} 3.18 mm. Adiabatic flows of air/water mixtures, with the flow channel horizontal and the channel exit at near-atmospheric conditions, were utilized in the experiments. Analysis and interpretation of the pressure data relative to observed flow pattern transitions led to an objective method for determining the plug/bubble-to-slug flow transition. This method, together with visual observations, supplemented with photographic data, was used to develop a flow pattern man. A comparison of existing flow pattern maps for circular ...

1990-05-01

303

Energy efficient fuzzy based combined variable refrigerant volume and variable air volume air conditioning system for buildings  

Energy Technology Data Exchange (ETDEWEB)

Energy conservative building design has triggered greater interests in developing flexible and sophisticated air conditioning systems capable of achieving enhanced energy-savings potential without sacrificing the desired thermal comfort and indoor air quality (IAQ). This research work greatly aimed at achieving enhanced energy conservation, good thermal comfort and better IAQ for space conditioning with the application of combined variable refrigerant volume (VRV) and variable air volume (VAV) air conditioning (A/C) systems. Experimental investigation on the proposed combined air conditioning system with the application of intelligent fuzzy logic controller was performed for summer and winter climatic conditions to substantiate the energy-savings capability. The proposed system experimentally analyzed under fixed ventilation, demand controlled ventilation (DCV) and combined DCV and economizer cycle (EC) ventilation techniques effectively conserved 44% and 63% of ...

2010-04-15

304

Vapor phase lubrication of a Ni-based superalloy  

Energy Technology Data Exchange (ETDEWEB)

In addition to ceramics, alloys such as tool steel and nickel- and iron-based superalloys are being considered for high temperature applications such as missile bearings and low heat rejection engines. Studies were made to lubricate a nickel-based superalloy at 500{degrees}C, by using a vaporized aryl phosphate ester, at a concentration of 0.1% in air. From deposition and wear studies it was found that it was impossible to form a good polymeric coating on the superalloy surface. Energy dispersive X-ray analyzer (EDXA) analysis showed that this was due to minute quantities of aluminum in the alloy segregating to the surface, upon being heated to 500{degrees}C, forming a passive oxide coating. It was necessary to activate the surface, in order to lubricate the material successfully. A method of activation by electrodepositing the surface with a layer of iron oxide was developed. Once activated, a good lubricous polymer was formed on the superalloy surface. Tests ...

1995-03-01

305

Synopsis of hydrologic data collected by waste management for characterization of unsaturated transport at Area G  

Energy Technology Data Exchange (ETDEWEB)

Data which have been collected by Los Alamos National Laboratory waste management for the hydrologic characterization of the subsurface at the low level radioactive waste disposal facility, Area G, are reported and discussed briefly. The data includes Unsaturated Flow Apparatus measurements of the unsaturated conductivity in samples from borehole G-5. Analysis compares these values to the predictions from van Genuchten estimates, and the implications for transport and data matching are discussed, especially at the location of the Vapor Phase Notch (VPN). There, evaporation drives a significant vapor flux and the liquid flux cannot be measured accurately by the UFA device. Data also include hydrologic characterization of samples from borehole G-5, Area G surface soils, Los Alamos (Cerros de Rio) basalt, Tsankawi and Cerro-Toledo layers, the Vapor Phase Notch (VPN), and additional new samples from the uppermost tuff layer at ...

1998-03-01

306

Studies about the separation of molecular species of hydrogen's isotopes by cryogenic distillation in a plant for heavy water detritiation  

Energy Technology Data Exchange (ETDEWEB)

Cryogenic distillation is the main industrial method for separating hydrogen's isotopes, because it presents the advantage of high separating factors and also the possibility of processing great quantities of gases. In the case of multicomponent mixtures the determination of transport for molecular species between the two phases is very difficult owing to the particularities of physical characteristics of each component from the mixture. The transport of molecular species is also strongly influenced by the hydrodynamics of two phases, in strong connection with the dimension of the interface between the vapor and liquid phase. The characteristics of the interface depend on the type and geometry of the separation area: plates or package. The traditional methods of analysis for exchange processes use the concept 'theoretic plate', a physical entity for which the values of concentrations for vapors and liquid that leaves ...

1998-07-01

307

Laboratory studies of gas generation and potential for tank wall corrosion during blending of high-level wastes at the West Valley Demonstration Project  

Energy Technology Data Exchange (ETDEWEB)

Laboratory experiments were conducted to simulate the transfer of acidic THOREX waste from Tank 8D-4 into the alkaline PUREX waste in Tank 8D-2 at West Valley. The purpose of the experiments was to explore means of minimizing the production of nitric oxide (NO) gas during mixing of the two wastes and to assess the potential for the gas to further react in the vapor space possibly leading to enhanced corrosion of the tank walls. Forty one THOREX/PUREX mixing tests were conducted to explore the effects of stirring rate, pH, THOREX addition rate, THOREX or PUREX dilution, and temperature. The two most important criteria for minimizing NO production were to maintain some degree of agitation and the keep the pH in the PUREX high, preferably >12. Steel corrosion tests were performed in the presence of low partial pressures of NO{sub 2} and liquid water or water vapor. The NO{sub 2} (from oxidation of NO in the vapor space) ...

1995-05-01

308

Investigation of natural circulation two-phase flow behaviour in header manifold using CFD code  

Energy Technology Data Exchange (ETDEWEB)

The three-dimensional (3-D), multiphase, computational fluid dynamic (CFD) code FLUENT is used to simulated two-phase flow behaviour in a CANDU header manifold under low (natural circulation) flow conditions. This behaviour was previously inferred from experimental data. The CFD simulations reported here are being used to support these inferences and to obtain a better understanding of phase distribution in the header manifold. The simulations seem to show that the vapor-water mixture models in the FLUENT code do not capture properly phase separation in the header and proper phase branching at the header-feeder connections that have been observed in experiments at low flows. The simulations using discrete-phase model in FLUENT, which tracks the pathlines of the individual vapor bubbles in the water continuum phase, show interesting, complicated and, in some cases, unexpected bubble trajectories from the point of injection of the bubbles at a ...

2006-07-01

309

Charts give vapor loss from internal floating-roof tanks  

Energy Technology Data Exchange (ETDEWEB)

Nomographs have been constructed to estimate the average evaporation loss from internal floating-roof tanks. Loss determined from the charts can be used to evaluate the economics of seal conversion and to reconcile refinery, petrochemical plant, and storage terminal losses. The losses represent average standing losses only. They do not cover losses associated with the movement of product into or out of the tank. The average standing evaporation loss from an internal floating-roof tank depends on: vapor pressure of the product; type and condition of roof seal; tank diameter; and type of fixed roof support. The nomographs can estimate evaporation loss for product true vapor pressures (TVP) ranging from 1.5 to 14 psia, the most commonly used seals for average and tight fit conditions, tank diameters ranging from 50 to 250 ft, welded and bolted designs, and both self-supporting and column-support fixed roof designs. The charts are purposely limited ...

1987-03-09

310

cw operation of an AlGaInP double heterostructure laser diode at 77 K grown by atmospheric metalorganic chemical vapor deposition  

Science.gov (United States)

Continuous wave operation of an Al/sub 0.21/Ga/sub 0.31/In/sub 0.48/P /Ga/sub 0.52/In/sub 0.48/P /Al/sub 0.21/Ga/sub 0.31/In/sub 0.48/P double heterostructure (DH) laser diode was achieved for the first time at 77 K. The device was made from a DH wafer grown by atmospheric metalorganic chemical vapor deposition using triethyl metals and phosphine as source materials. At 77 K, the lasing wavelength was 0.653 ..mu..m and the threshold current was 55 mA for a diode with a nitride-insulated, 8-..mu..m-wide and 250-..mu..m-long stripe geometry.

1984-09-15

311

Waste minimization in a non-production oriented metal finishing operation  

Energy Technology Data Exchange (ETDEWEB)

This paper provides information on activities undertaken in a non- production oriented metal finishing operation to minimize waste and conserve resources. The facility is a 6000 sq foot shop that typically only deals with prototype parts. Utilizing a plan that includes employee awareness, common sense and existing technology, a noticeable reduction in waste volume has been obtained. Initiatives that are covered include: segregation of cyanide plating solutions, elimination of copper cyanide plating, elimination of hexavalent chromium plating, elimination of vapor degreasing, changing of rinsing practices, and changing a process for cleaning of aluminum parts. Some discussion is also presented on the effectiveness of combining the technologies of physical vapor deposition and electrodeposition to help minimize waste. Plans for additional initiatives including water recycling, elimination of cyanide plating and substitution of electrodeposition ...

1991-11-01

312

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 reduced insolation, and an alternative process is described for operation of the ...

1982-12-14

313

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

314

Tank 241-AZ-101 Mixer Pump Test Vapor Sampling and Analysis Plan  

Energy Technology Data Exchange (ETDEWEB)

This sampling and analysis plan (SAP) identifies characterization objectives pertaining to sample collection, laboratory analytical evaluation, and reporting requirements for vapor samples obtained during the operation of mixer pumps in tank 241-AZ-101. The primary purpose of the mixer pump test (MPT) is to demonstrate that the two 300 horsepower mixer pumps installed in tank 241-AZ-101 can mobilize the settled sludge so that it can be retrieved for treatment and vitrification. Sampling will be performed in accordance with Tank 241-AZ-101 Mixer Pump Test Data Quality Objective (Banning 1999) and Data Quality Objectives for Regulatory Requirements for Hazardous and Radioactive Air Emissions Sampling and Analysis (Mulkey 1999). The sampling will verify if current air emission estimates used in the permit application are correct and provide information for future air permit applications.

2000-04-10

315

Separation of magnesium from magnesium chloride and zirconium and/or hafnium subchlorides in the production of zirconium and/or hafnium sponge metal  

International Nuclear Information System (INIS)

This patent describes the producing of a refractory metal wherein a sponge refractory metal is produced as an intermediate product by the use of magnesium with the incidental production of magnesium chloride, and wherein residual magnesium is separated from the magnesium chloride and from refractory metal to a vacuum distillation step which fractionally distills the magnesium, the magnesium chloride, and the metal sub-chlorides; the steps of: recovering fractionally distilled vapors of magnesium chloride and metal sub-chlorides from a sponge refractory metal; separately condensing the vapors as separately recovered; and recycling the separately recovered magnesium at a purity of at least about 96%.

1990-09-21

316

Selective formation of ZnO nanodots on nanopatterned substrates by metalorganic chemical vapor deposition  

International Nuclear Information System (INIS)

Selective formation of ZnO nanodots was accomplished by metalorganic chemical vapor deposition on nanopatterned SiO_2/Si substrates. Self-organized ZnO nanodots were selectively formed in nanopatterned lines of Si created by etching of SiO_2 with focused ion beam (FIB), whereas any nanodots were hardly observed on the SiO_2 surface in the vicinity of the FIB-sputtered Si areas. The mechanism of the selective formation of ZnO nanodots on FIB-nanopatterned lines is mainly attributed to the effective migration of Zn adatoms diffusing on the SiO_2 surface into the Si lines followed by the nucleation at surface atomic steps and kinks created by Ga"+ ion sputtering. Cathodoluminescence measurements confirmed that the emission originated from the selectively grown ZnO nanodots.

2003-10-27

317

Room-temperature continuous-wave operation of a GaInP/AlGaInP multiquantum well laser grown by metalorganic chemical vapor deposition  

Science.gov (United States)

Room-temperature continuous-wave (cw) operation of a GaInP/AlGaInP multiquantum well (MQW) laser was achieved for the first time. The threshold current was 70 mA at 22 /sup 0/C for a device with an 8-..mu..m-wide and a 250-..mu..m-long planar stripe. The emission wavelength was 668 nm. The characteristic temperature T/sub 0/ was 138 K under cw operation. The wafer with the MQW structure composed of 100-A-thick GaInP wells and 40-A-thick AlGaInP barrier layers was grown by atmospheric pressure metalorganic chemical vapor deposition.

1987-04-20

318

Photocatalytic degradation of gaseous pyridine over zeolite-supported titanium dioxide  

Energy Technology Data Exchange (ETDEWEB)

The photocatalyzed degradation of pyridine in the gas phase was investigated using titanium dioxide semiconductor supported on mordenite. The complete mineralization was found to occur over a catalyst containing 75 wt% TiO{sub 2} and 25 wt% mordenite in about 180 min in the presence of saturated water vapor at O{degrees}C (4.6 Torr). Low water vapor pressure of 0.096 Torr was found to be sufficient to achieve a reasonably high percentage and rate of degradation. Diffusion of pyridine within the catalyst adversely affects the activity when the thickness of the catalyst coating exceeds the penetration depth of illumination. The activity of the zeolite-supported catalysts was higher than that of TiO{sub 2}. The photonic efficiency for the complete mineralization of pyridine to CO{sub 2} was determined to be 0.48. 29 refs., 6 refs., 1 tab.

1994-09-01

319

PROBING NEAR-SURFACE ATMOSPHERIC TURBULENCE WITH LIDAR MEASUREMENTS AND HIGH-RESOLUTION HYDRODYNAMIC MODELS  

Energy Technology Data Exchange (ETDEWEB)

As lidar technology is able to provide fast data collection at a resolution of meters in an atmospheric volume, it is imperative to promote a modeling counterpart of the lidar capability. This paper describes an integrated capability based on data from a scanning water vapor lidar and a high-resolution hydrodynamic model (HIGRAD) equipped with a visualization routine (VIEWER) that simulates the lidar scanning. The purpose is to better understand the spatial and temporal representativeness of the lidar measurements and, in turn, to extend their utility in studying turbulence fields in the atmospheric boundary layer. Raman lidar water vapor data collected over the Pacific warm pool and the simulations with the HIGRAD code are used for identifying the underlying physics and potential aliasing effects of spatially resolved lidar measurements. This capability also helps improve the trade-off between spatial-temporal resolution and coverage of the ...

2000-11-01

320

Optoelectronic devices grown by metallo-organic chemical vapor deposition  

International Nuclear Information System (INIS)

The metallo-organic chemical vapor deposition (MOCVD) process has been used with great success to grow AlGaAs-GaAs and InGaAsP-InGaAs-InP heterostructure materials for electronic and optoelectronic applications. Devices fabricated from Al/sub x/Ga/sub 1-x/As-GaAs heterostructures grown by MOCVD include bipolar transistors, field-effect transistors (FETs), high-mobility (or modulation-doped) FETs, large-area high-efficiency solar cells, low-threshold lasers, high-power lasers, quantum-well lasers, and visible lasers. The state of the art for the MOCFD growth of optoelectronic devices is reviewed in this paper, and some comments are made regarding future trends in the growth of these materials by MOCVD.

321

Microgravity two-phase flow regime modeling  

Energy Technology Data Exchange (ETDEWEB)

A flow pattern or flow regime is the characteristics spatial distribution of the phases of fluid in a duct. Since heat transfer and pressure drop are dependent on the characteristic distribution of the phases, it is necessary to describe flow patterns in an appropriate manner so that a hydrodynamic or heat transfer theory applicable to that pattern can be chosen. The objective of the present analysis is to create a flow regime map based on physical modeling of vapor/liquid interaction phenomena in a microgravity environment. In the present work, four basic flow patterns are defined: dispersed flow, stratified flow, slug flow, and annular flow. Fluid properties, liquid and vapor flow rates, and pipe size were chosen as the principal parameters. It is assumed that a transition from one flow pattern to another will occur when there is a change in the dominant force which controls that flow pattern. The forces considered in this modeling are ...

1987-01-01

322

Mechanism of the electric field effect on the intensity of visible continuum emission from the positive column of gas discharge in a cesium vapor-xenon mixture  

British Library Electronic Table of Contents (United Kingdom)

We have studied the nature of continuum emitted in the visible spectral range from a noncontracted positive column of discharge in a cesium vapor-xenon mixture at a pressure of 45 Torr and at a degree of ionization below 3 ? 10?6. The main contribution to the continuous emission under such conditions is due to electron-xenon atom bremsstrahlung. The intensity of emission has been experimentally and theoretically studied as a function of the electric field strength and electron density in the positive column. It is established that an increase in the visible emission intensity with the electric field strength is related to an increase in the number of hot electrons in plasma.

2007-01-01

323

Experimental investigation of wall static pressure fluctuations in parallel boiling flow  

International Nuclear Information System (INIS)

Measurements of the statistical characteristics of channel wall static pressure fluctuations in parallel one-component boiling flow are reported. The measurements span a wide range of local subcooling and vapor volume fraction, and correspond to flow regimes ranging from highly subcooled bubbly to saturated slug-annular. Vapor volume fraction measurements at the pressure measurement station are also reported in conjunction with visual observation of the flow structure. Variation of static pressure fluctuation intensity and spectral content with local thermal-hydraulic condition is demonstrated. Finally, it is suggested that diagnosis of local two-phase flow regime on the basis of (i) statistical characteristics of the pressure data, and (ii) time trace of pressure signal, may be possible. 15 refs.

1980-01-01

324

Excess Gibbs free energies and excess volumes of mixtures containing normal alkanes or cyclohexane + thiaalkanes or dithiaalkanes  

Energy Technology Data Exchange (ETDEWEB)

Vapor-liquid equilibria, by head-space gas-chromatographic analysis of the equilibrated vapor phase directly withdrawn from the equilibration apparatus, and molar excess volumes, V[sup E], by means of a vibrating-tube densimeter, of binary mixtures containing thiaalkanes or dithiaalkanes with n-alkanes or cyclohexane, were determined at 298.15 K. The excess molar Gibbs free energies, GE, of the examined mixtures were obtained by a least-squares treatment of the equilibrium data. The GE and V[sup E] values indicate that the steric effect exerted by the alkyl groups adjacent to the S group causes a regular decrease of the G[sup E] (or V[sup E]) with increasing the number of alkyl groups in the thiaalkane. A tentative approach, based on an additivity scheme of surface interactions combined with the scaled particle theory, is presented to estimate the energies of solvation in terms of group contributions.

1993-10-01

325

Elucidating two-phase transport in a polymer electrolyte fuel cell, Part 1: Characterizing flow regimes with a dimensionless group  

British Library Electronic Table of Contents (United Kingdom)

This paper explores the through-/in-plane characteristics of water transport in the cathode gas diffusion layer (GDL) of a polymer electrolyte fuel cell (PEFC). Theoretical analysis is performed on the non-isothermal two-phase flow under flow channels. A dimensionless group Da (Damkohler number for PEFC operation), defined as the ratio of water generation rate to water vapor-phase removal rate, is formulated to characterize the flow regimes in a PEFC. This group, lumping geometrical parameters and physical properties, compares the water vapor-phase removal capability (via water diffusion and holding capacity) with the rate of water production by the oxygen reduction reaction. We find that this dimensionless group can be used to characterize the non-isothermal, two-phase phenomena: when Da&...

2011-01-01

326

Demonstration of a Tunable-Bandwidth White Light Interferometer using Anomalous Dispersion in Atomic Vapor  

CERN Document Server

The concept of the 'white-light cavity' has recently generated considerable research interest in the context of gravitational wave detection. Cavity designs are proposed using negative (or anomalous) dispersion in an intracavity medium to make the cavity resonate over a large range of frequencies and still maintain a high cavity build-up. This paper presents the first experimental attempt and demonstration of white-light effect in a meter long ring cavity using an intracavity atomic medium. The medium's negative dispersion is caused by bi-frequency Raman gain in an atomic vapor cell. Although the white light condition was not perfectly achieved and improvements in experimental control are still desirable, significantly broad cavity response over bandwidth greater than 20 MHz has been observed. These devices will have potential applications in new generation laser interferometer gravitational wave detectors.

2006-01-01

327

A novel accelerated oxidative stability screening method for pharmaceutical solids  

British Library Electronic Table of Contents (United Kingdom)

Abstract Despite the fact that oxidation is the second most frequent degradation pathway for pharmaceuticals, means of evaluating the oxidative stability of pharmaceutical solids, especially effective stress testing, are still lacking. This paper describes a novel experimental method for peroxide-mediated oxidative stress testing on pharmaceutical solids. The method utilizes urea-hydrogen peroxide, a molecular complex that undergoes solid-state decomposition and releases hydrogen peroxide vapor at elevated temperatures (e.g., 30C), as a source of peroxide. The experimental setting for this method is simple, convenient, and can be operated routinely in most laboratories. The fundamental parameter of the system, that is, hydrogen peroxide vapor pressure, was determined using a modified spect...

2011-01-01

328

A mobile remote sensing laboratory for water vapor, trace gas, aerosol, and wind speed measurements  

Energy Technology Data Exchange (ETDEWEB)

The Lawrence Livermore National Laboratory has developed a mobile field laboratory for remote measurement of atmospheric processes and observables that are important in global climate change, dispersal of hazardous materials, and atmospheric pollution. Specific observables of interest are water vapor, trace gases, aerosol size and density, wind, and temperature. The goal is to study atmospheric processes continuously for extended periods in remote field locations. This laboratory has just reached field ready status with sensors for aerosol and trace gas measurement based on established techniques. A development program is underway to enhance the sensor suite with several new techniques and instruments that are expected to significantly extend the state of the art in remote trace gas analysis. The new sensors will be incorporated into the lab during the next two years.

1993-03-19

329

The compressive strength of cement blocks permeated with an organic phase change material  

Energy Technology Data Exchange (ETDEWEB)

The authors investigate the feasibility of constructing walls and partitions with enhanced heat storage capability from cement blocks permeated with an organic phase change material (pressed stearic acid). The blocks are lightweight, easy to produce and are cured in the same way as cement or concrete. The ratio of components (cement, stearic acid (SA) and water) was optimized with respect to compressive strength. With normal portland cement, the best compressive strength 2.2 MPa was obtained with a ratio C:SA:W of 1:0.8:0.65 (i.e. 32% stearic acid) after 28 days of curing. This was increased to 4.4 MPa when high early strength cement was used, about as strong as Sipporex, lightweight concrete or lightweight clay bricks. As expected, the compressive strength decreased linearly with temperature between 25/sup 0/C and 100/sup 0/C, at a rate of 15 kPa//sup 0/C. The drying shrinkage of the modules was found to be 50% greater ...

1984-01-01

330

Origins of residual stress in Mo and Ta films: The role of impurities, microstructural evolution, and phase transformations  

Energy Technology Data Exchange (ETDEWEB)

Both the sign and magnitude of residual stress can vary with the thickness of sputter deposited films. The origins of this behavior are not well understood. In this work, the authors consider the correlation between the residual stress behavior and the depth dependence of impurities in thin (2.5 nm--150 nm) sputtered Mo and Ta films. They also consider the effects of phase transformations and microstructural changes on the stress behavior. Films were deposited onto Si substrates with native oxide. The residual stress observed in the Mo films varied from highly compressive at 2.5 nm film thickness to {approximately}0 at 10 nm thickness. Ta films also exhibited a high compressive stress, which relaxed from highly compressive to tensile between 10 nm and 50 nm film thickness. Impurities in the films may originate from the sputtering targets, the background gases, and the substrate surfaces. Auger Electron Spectroscopy (AES) ...

1997-05-01

331

Intravertebral body reconstruction with an injectable in situ-setting carbonated apatite: biomechanical evaluation of a minimally invasive technique.  

Science.gov (United States)

The ability to mechanically reinforce an osteoporotic vertebral body could impede spinal compression fracture and the associated pain and complications. Previous studies have shown that reinforcement of fractured vertebrae with conventional acrylic cement can relieve symptoms and avoid further collapse. In this study, we explored the use of a carbonated apatite cement combined with a minimally invasive injection technique to improve the compressive mechanical properties of cadaveric vertebral bodies. After establishing the biomechanical characteristics of cement formulations intended to have appropriate viscosities, we evaluated the infiltration of the cements into thoracic vertebral bodies using a combined suction-injection technique. The energy-absorption capabilities of the reinforced vertebral bodies were then measured during axial compressive tests and compared with those of nonreinforced vertebrae. The ultimate ...

1999-01-01

332

Flow characteristics and dynamics of swing check valves in compressible flow applications (Part-1)  

Energy Technology Data Exchange (ETDEWEB)

In the design of natural gas compressor stations, a check valve is a critical element which is commonly placed on the discharge side of the compressor to prevent reverse flow that can cause serious damage to the compressor itself and other components such as seals and bearings. One of the selection criteria of the check valve for this particular application is the valve flow characteristics in steady flow, and its dynamic characteristics in unsteady flow operation. With regards to steady flow valve characteristics, current models for the determination of the check valve open angle vs. mean flow velocity are based on semi-empirical data obtained from water tests, which were found to deviate from measurements in compressible flows. This paper presents results of steady compressible flow testing of an NPS 4 swing type check valve in air. Mean flow velocities vs. disc angles were measured together with several local pressure measurements at the ...

1996-12-01

333

Structural adaptation and intracortical bone turnover in an ovine model of osteoporosis.  

Science.gov (United States)

Compact bone makes up approximately 80% of the human skeletal mass. This study examines the effect of estrogen deficiency on compact bone turnover and associated geometrical structural adaptation over a 31-month period in a large animal model. Twenty-seven skeletally mature sheep were divided into control (n = 16) and ovariectomy group (OVX, n = 11). Animals were administered five different fluorochrome dyes to label intracortical bone turnover, and sacrificed at 31 months. Compact bone samples were analyzed for cortical geometry, intracortical turnover at five time points, resorption cavities, porosity, and compressive strength. Intracortical bone turnover was significantly increased in OVX, which demonstrated seasonal variation. Cross-sectional area in OVX was significantly greater than control and was associated with an increased section modulus. Intracortical porosity was significantly increased in OVX, however, there was no significant difference in ultimate ...

2010-02-01

334

Some mechanical properties of goose femoral cortical bone.  

Science.gov (United States)

The ultimate compressive strength and modulus of elasticity of femoral cortical bone from adult geese (Anser anser), were determined by sex and by quadrant by compressing small right circular cylinders which were 2.4 mm in height and 0.8 mm in diameter. The average ultimate compressive strength was 183 +/- 29 MPa. The average modulus of elasticity was 13.2 +/- 3.4 GPa. The bending strength and bending modulus of elasticity were determined by a three point bend test on rectangular prisms which had the approximate dimensions 0.75 mm X 0.75 mm X 25 mm. The average bending strength was 263 +/- 44 MPa while the average bending modulus was 19.6 +/- 3.1 GPa. The calcium content was determined by atomic absorption spectrophotometry and no correlation was found with the mechanical properties. The histology of the cortical bone was examined both quantitatively and qualitatively. A unique type of Haversian bone is described. Goose ...

1983-01-01

335

Microstructure engineering from metallic powder blends for enhanced mechanical properties  

International Nuclear Information System (INIS)

The present work focuses on the transformation of high-purity Ni powder blends of controlled volume fractions (40 and 60 %) of nanometre-sized (100 nm) and micrometre-sized (544 nm) particles into bulk samples as part of a strategy for producing ultrafine-grained materials usefully exhibiting both strength and ductility. The process involved cold isostatic pressing at 1.5 GPa and sintering. The resulting bulk samples had relative densities near 95 %, were texture-free, and exhibited two different grain size distributions with an average value of 600 #+-# 30 nm. The mechanical properties were investigated by compression and microhardness tests, both at room temperature, and compared to the behaviour of a sample processed from micrometre-sized powder only. Samples prepared from the blends exhibited high yield stresses of 440 and 550 MPa after compression, and they did sustain work hardening. Tests conducted before and after ...

2010-07-01

336

Enhancing compressive response of AZ31B using nano-Al2O3 and copper additions  

British Library Electronic Table of Contents (United Kingdom)

In the present study, new light weight nano-composites (AZ31B-3.3Al2O3-Cu) based on magnesium alloy AZ31B are developed using disintegrated melt deposition technique. Microstructural characterization studies revealed grain refinement and significant increase in amount of second phases as a result of increasing presence of copper. All the samples exhibited minimal porosity and good matrix-second phase interfacial integrity. The results also showed that addition of both nano-Al2O3 and Cu led to a simultaneous improvement in 0.2% yield compressive strength (0.2%YCS), ultimate compressive strength (UCS) and work of fracture (WoF) of the AZ31B magnesium alloy while failure strain was marginally affected. The results of this study clearly illustrate the capability of AZ31B-Al2O3-Cu formulations ...

2010-01-01

337

Data Compression on Zero Suppressed High Energy Physics Data  

CERN Document Server

Future High Energy Physics experiments will produce unprecedented data volumes (up to 1 GB/s [1]). In most cases it will be impossible to analyse these data in real time and they will have to be stored on durable mostly magnetic linear media (e.g. tapes) for later analysis. This threatens to become a major cost factor for the running of these experiments. Here we present some ideas developed together with the Institute of Computer Graphics, Department for Algorithms and Programming on how this volume and the related cost can be reduced significantly. The algorithms presented are not general ones but aimed in particular to physics experiments data. Taking advantage of the knowledge of the data they are highly superior to general ones (Huffman, LZW, arithmetic coding) both in compression rate but more importantly in speed as to keep up with the output rate to modern tape drives. Above standard algorithms are, however, used after the data have been transferred in a ...

1996-01-01

338

Compressed-shell integrity measurements in spherical implosion experiments  

International Nuclear Information System (INIS)

The shell integrity near peak compression of spherical implosions using the 60-beam, 30-kJ UV OMEGA laser system [Opt. Commun. 133, 495 (1997)] has been measured. Hot core emission backlights a shell with a thin titanium-doped layer that is imaged at x-ray photon energies above and below the titanium K edge. The x-ray intensity ratio between the two images is related to perturbations in the cold, or absorbing, part of the shell. The measured cold-shell areal-density modulations, integrated over the time of peak compression, are of the order of 25% to 50% with nonuniformity spectra peaked at spatial wavelengths of 30 to 50 #mu#m and with the smallest detectable nonuniformity features extending down to spatial wavelengths of 12 to 15 #mu#m. Hot-shell areal-density modulations of the emitting part of the shell (inner edge) are of the order of 13% to 20%. The measured shell modulations are in agreement with the results of two-dimensional ...

2001-06-01

339

Compressed Counting  

CERN Document Server

Counting is among the most fundamental operations in computing. For example, counting the pth frequency moment has been a very active area of research, in theoretical computer science, databases, and data mining. When p=1, the task (i.e., counting the sum) can be accomplished using a simple counter. Compressed Counting (CC) is proposed for efficiently computing the pth frequency moment of a data stream signal A_t, where 0= 0, which includes the strict Turnstile model as a special case. For natural data streams encountered in practice, this restriction is minor. The underly technique for CC is what we call skewed stable random projections, which captures the intuition that, when p=1 a simple counter suffices, and when p = 1+/\\Delta with small \\Delta, the sample complexity of a counter system should be low (continuously as a function of \\Delta). We show at small \\Delta the sample complexity (number of projections) k = O(1/\\epsilon) instead of O(1/\\epsilon^2). ...

2008-01-01

340

Centrifugal potential energy : an astounding renewable energy concept  

Energy Technology Data Exchange (ETDEWEB)

A new energy concept known as centrifugal potential energy was discussed. This new energy concept is capable of increasing the pressure, temperature and enthalpy of a fluid, without having to apply work or heat transfer to the fluid. It occurs through a change in the centrifugal potential energy of the flowing fluid in a rotating frame of reference or a centrifugal force field, where work is performed internally by the centrifugal weight of the fluid. This energy concept has resulted in new energy equations, such as the Rotational Frame Bernoulli's Equation for liquids and the Rotational Frame Steady-Flow Energy Equation for gases. Applications of these equations have been incorporated into the design of centrifugal field pumps and compressors. Rather than compressing a fluid with a physical load transfer, these devices can compress a fluid via the effect of centrifugal force applied to the object. A large amount of energy is therefore ...

2010-07-01

341

Apparatus for producing blast furnace coal  

Science.gov (United States)

A method of producing blast furnace coke from bituminous coals, particularly coals having poor coking capacities in which the coal to be carbonized is ground, predried or preheated, mixed with binders, compressed or formed into briquets having small mechanical resistances and charged into oven chambers, is characterized by fine coals or fine coal mixtures having a swelling index in mixture according to DIN 51741, smaller than 7, and preferably, below 6, and comprising more than 50% of poorly or non-baking coal having a content of volatile matter in excess of 30% or less than 20% which coals or coal mixtures are ground up to attain a surface per unit mass, according to DIN 66145, of from 400 cm/sup 2/ to 1200 cm/sup 2/ per gram, with from 3% to 8% by weight of organic binders, compressing the mixture to form it into a briquet at a temperature range of from 70/sup 0/C to 300/sup 0/C and charging the compressed briquet into ...

1979-06-19

342

A Numerical Algorithm for Determining the Contact Stress of Circular Crowned Roller Compressed between Two Flat Plates  

Science.gov (United States)

The main purpose of this paper is to explore a numerical algorithm for determining the contact stress when a circular crowned roller is compressed between two plates. To start with, the deformation curve on a plate surface will be derived by using the contact mechanical model. Then, the contact stress distribution along the roller which occurs on the plate surface is divided into three parts: from the center of contact to the edge, the edge and apart from the contact line. The first part is calculated by the elastic contact theorem for the contact subjected to nominal stress between non-crowned parts of roller and plates, the second part is obtained by the classical Hertzian contact solution for the contact between crowned parts of roller and plates, and the third part is simulated as exponential decay. In order to overcome the defect of the half space theorem, in which a plate with infinite thickness is assumed initially, a weighting method is introduced to find ...

2007-01-01

343

ul'as , 8L6T 'TE -X@qLuaDaCI 142nOzT,14 SL61 'I AeW -SG4'eC[ lpa ...  

Science.gov (United States)

Superconductivity of A-15 Compounds in the-System Nb-Ge-Sn Synthesized by Chemical Vapor Deposition, -. J. Engelhardt and G. W. Webb, ...

344

U.S. Department of Energy, Nevada Operations Office Environmental Monitoring Program, Summary Data Report, First Calendar Quarter 1996  

Energy Technology Data Exchange (ETDEWEB)

This report discusses environmental surveillance activities conducted on the Nevada Test Site during the first calendar quarter of 1996. Surveillance activities included collection and analysis of air, noble gas, tritiated water vapor, and other water samples. Samples were analyzed for both radiological and non-radiological effluents.

1996-11-01

345

Thermal fatigue failure at the White Cliffs solar thermal power plant  

Energy Technology Data Exchange (ETDEWEB)

The failure of receivers has been one of the main operating problems at the White Cliffs solar thermal power plant. This Technical Note reports the results of an initial investigation that identifies the cause as having been their thermal fatiguing of the tube walls. The fatigue appears to be caused by unstable heat transfer at vapor qualities below the point where critical heat flux is generally exceeded. Methods for avoiding this problem are tested.

1995-02-01

346

Spray Chemical Vapor Deposition of Single-Source Precursors for Chalcopyrite I-III-VI2 Thin-Film Materials  

Science.gov (United States)

Thin-film solar cells on flexible, lightweight, space-qualified substrates provide an attractive approach to fabricating solar arrays with high mass-specific power. A polycrystalline chalcopyrite absorber layer is among the new generation of photovoltaic device technologies for thin film solar cells. At NASA Glenn Research Center we have focused on the development of new single-source precursors (SSPs) for deposition of semiconducting chalcopyrite materials onto lightweight, flexible substrates. We describe the syntheses and thermal modulation of SSPs via molecular engineering. Copper indium disulfide and related thin-film materials were deposited via aerosol-assisted chemical vapor deposition using SSPs. Processing and post-processing parameters were varied in order to modify morphology, stoichiometry, crystallography, electrical properties, and optical properties to optimize device quality. Growth at atmospheric pressure in a horizontal hotwall reactor at 395 C ...

2008-01-01

347

Pyrolysis of dichlorodithiourea cadmium(II)  

Energy Technology Data Exchange (ETDEWEB)

By means of infrared spectroscopy, x-ray diffraction, and differential thermal analysis, the authors investigate the pyrolysis of dichlorodithiourea cadmium, the vapor phase epitaxy of the cadmium sulfide film, and the composition of the solid and gaseous pyrolysis products. Those products are found to include the thiocyanates of guanidine, ammonium, and hydrogen along with cadmium oxides and sulfates and hydrochloric acid.

1987-02-20

348

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

349

Operational test report integrated system test (ventilation upgrade)  

Energy Technology Data Exchange (ETDEWEB)

Operational Final Test Report for Integrated Systems, Project W-030 (Phase 2 test, RECIRC and HIGH-HEAT Modes). Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks, including upgraded vapor space cooling and filtered venting of tanks AY101, Ay102, AZ101, AZ102.

1999-10-05

350

Nodalization schemes for PGV-440 steam generator model with RELAP5/MOD3  

Energy Technology Data Exchange (ETDEWEB)

Results of calculation of steady thermal-hydraulic characteristics of PVG-440 horizontal steam generator are presented. Steam flows in selected sections are compared to data provided by OKB Gidropress Calculated vapor void fractions are compared to measured ones. (orig.) (3 refs., 3 figs., 8 tabs.).

1993-12-31

351

Nodalization schemes for PGV-440 steam generator model with RELAP5/MOD3  

International Nuclear Information System (INIS)

Results of calculation of steady thermal-hydraulic characteristics of PVG-440 horizontal steam generator are presented. Steam flows in selected sections are compared to data provided by OKB Gidropress Calculated vapor void fractions are compared to measured ones. (orig.) (3 refs., 3 figs., 8 tabs.).

1992-09-29

352

Laser induced fluorescence measurements of the mixing of fuel oil with air  

Energy Technology Data Exchange (ETDEWEB)

We report on measurements of the mixing of fuel oil with air at atmospheric pressure in an industrial premixed gas turbine burner. The concentration of the vaporized fuel oil was measured with laser induced fluorescence. We reason that the fuel oil concentration can be considered with good accuracy as proportional to the fluorescence intensity. (author) 6 fig., 3 refs.

1999-08-01

353

Kinetics of achieving equilibrity at the sorption of radionuclides  

International Nuclear Information System (INIS)

Radionuclide (R) sorption from a solution (vapor) by freshly formed crystals with production of substitution solid solutions under different types of self-disordering is studied. Changes of self-defectiveness and macrodefectiveness with time and effect of radiation defects in the presence of P macroquantities are taken into account. An analysis for monodispersed sorbents is performed. It is shown that the achievement of equilibrium within a reasonable time in impurity-solid phase system depends on defectiveness which ensures a required level of the coefficient of impurity diffusion in sorbent crystals.

354

Heat transfer in boiling liquified gas  

Energy Technology Data Exchange (ETDEWEB)

Means for increasing heat transfer characteristics between the surface of a solid and a boiling liquid are described in which the solid is immersed is comprised of a solid with passages which extend therethrough to the surface for the circulation of liquid through the passages for emergence from the surface to eliminate at least a portion of the unstable vapor film otherwise formed on the surface.

1980-09-23

355

Enhanced Control of Mercury by Wet Flue Gas Desulfurization Systems Site 3 Topical Report.  

Science.gov (United States)

The U.S. Department of Energy and EPRI have co-funded this project to improve the control of mercury emissions from coal-fired power plants equipped with wet flue gas desulfurization (FGD) systems. The project investigated catalytic oxidation of vapor-pha...

2004-01-01

356

Electrophysical properties of supramolecular films of the germanium-oxyethylidenediphosphonic acid complex  

International Nuclear Information System (INIS)

The structure of a fragment of the germanium complex compound (GCC) with oxyethylidenediphosphonic acid and the adsorption properties of GCC films with respect to the vapors of water and some other organic liquids have been studied. The electric conductivity of GCC films has been investigated, and its mechanism has been explained.

2005-04-01

357

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

358

A review of mesospheric dynamics and chemistry  

Energy Technology Data Exchange (ETDEWEB)

Advances made in understanding the chemistry and dynamics of the atmosphere in the approximate altitude range of 50 to 90 km are addressed. Attention is given to mesospheric structure and seasonal variations, gravity waves and gravity wave saturation, the effects of gravity waves on thermal, momentum and constituent fluxes, and the effect of gravity waves on airglow emissions. A review of research on tides and planetary waves and their effects on the mesosphere are presented as well as discussions on ozone hydroxyl, water vapor, and noctilucent cloud research. 217 refs.

1991-01-01

359

A 3D tomographic EBSD analysis of a CVD diamond thin film  

Energy Technology Data Exchange (ETDEWEB)

We have studied the nucleation and growth processes in a chemical vapor deposition (CVD) diamond film using a tomographic electron backscattering diffraction method (3D EBSD). The approach is based on the combination of a focused ion beam (FIB) unit for serial sectioning in conjunction with high-resolution EBSD. Individual diamond grains were investigated in 3-dimensions particularly with regard to the role of twinning.

2008-09-15

360

The effects of a calcium deficient diet on the mechanical properties and morphology of goose bone.  

Science.gov (United States)

A control group of geese (Anser anser) on a normal calcium diet for egg laying poultry was compared to egg laying geese on a calcium deficient diet. The ultimate compressive strength and modulus of elasticity of femoral cortical bone from each group were determined by compressing right circular cylinders which were 2.4 mm in height and 0.8 mm in diameter. The bending strength and bending modulus of elasticity of tibial cortical bone were determined by three point bend tests on rectangular prisms which were approximately 25 mm by 0.8 mm by 0.8 mm. Bone calcium content and eggshell calcium content were determined by atomic absorption spectrophotometry. Blood samples were analyzed for free calcium ion concentration. Histological observations included studies of cross-sectional microradiographs, examinations of cross sections stained by a modified Masson's technique, and a determination of fractional area of voids by quantitative microscopy. The ...

1986-01-01

361

Wound ballistics of gunshot injuries to the head and neck.  

Science.gov (United States)

It is important for the trauma surgeon to understand the basic principles of terminal gunshot ballistics and the study of the projectile's effect on striking soft tissue. The amount of kinetic energy dissipated to the tissue is directly related to the mass and velocity of the projectile as follows: K = MV2/2. Doubling the velocity quadruples the energy, while doubling the mass only doubles the energy. A temporary tissue cavity is produced as the striking projectile compresses the surrounding tissue; the higher the energy release, the more extensive the inapparent compressive damage. The permanent cavity that remains is the result of extrusion of tissue from the pathway of the projectile. The higher the velocity, the higher the likelihood of extensive damage. If the missile expands or fragments within the tissues, more damage will occur. PMID:6847483

1983-05-01

362

Use of thin glass reflectors for solar concentrators  

Science.gov (United States)

Elastically deforming thin glass (thickness = 0.13 to 0.80 mm) provides an alternate method of forming a curved glass reflector which can eliminate some of the disadvantages of thicker glass. A concept is described where silvered thin glass is bonded to a steel backing to form a laminate with a reflectance greater than 93%. Subsequent bending of the flat reflector laminate to a concentrating profile produces compressive stresses throughout the glass if the laminate is properly designed. These compressive stresses enhance fracture resistance and the lamination provides protection for the silver. The design of the laminate is outlined for 0.25 and 0.51 mm thickness glass and fabrication procedures are discussed. Thermal/humidity cycling, hail impact, bond strength measurements and reflectance results are presented which demonstrate the performance capabilities of this reflector laminate concept.

1980-01-01

363

Temperature dependence of density and compressibility of eutectic mixtures of alkali metal chlorides near melting point  

International Nuclear Information System (INIS)

Hydrostatic weighing was used to measure the pre-melt density of crystalline eutectic mixtures of alkaline metal chlorides of the compositions (mole fractions): 0.605 LiCl + 0.395 CsCl, 0.585 LiCl + 0.415 KCl, 0.297 NaCl + 0.246 KCl + 0.457 CsCl, and 0.348 NaCl + 0.652 CsCl with melting points 598, 628, 753, 763 K, respectively, as a function of temperature. In the same temperature ranges, the compressibility and molar volume of eutectics as well as their sudden change upon melting were estimated. Unusual variations of these properties were revealed near the crystal/liquid phase transition, which were related to local disordering of particle configuration

364

Straight vegetable oils usage in a compression ignition engine-A review  

British Library Electronic Table of Contents (United Kingdom)

The ever increasing fossil fuel usage and cost, environmental concern has forced the world to look for alternatives. Straight vegetable oils in compression ignition engine are a ready solution available, however, with certain limitations and with some advantages as reported by many researchers. A comprehensive and critical review is presented specifically pertaining to straight vegetable oils usage in diesel engine. A detailed record of historical events described. Research carried out specifically under Indian conditions and international research work on the usage of straight vegetable oils in the diesel engine is separately reviewed. Many researchers have reported that straight vegetable oils in small percentage blends with diesel when used lower capacity diesel engines have shown great...

2010-01-01

365

Preparation and evaluation of a novel glass-ionomer cement with antibacterial functions  

British Library Electronic Table of Contents (United Kingdom)

Objective.The objective of this study was to use the newly synthesized poly(quaternary ammonium salt) (PQAS)-containing polyacid to formulate the light-curable glass-ionomer cements and study the effect of the PQAS on the compressive strength and antibacterial activity of the formed cements.Materials and methods.The functional QAS and their constructed PQAS were synthesized, characterized and formulated into the experimental high-strength cements. Compressive strength (CS) and Streptococcus mutans viability were used to evaluate the mechanical strength and antibacterial activity of the cements. Fuji II LC cement was used as control. The specimens were conditioned in distilled water at 37 degrees C for 24 h prior to testing. The effects of the substitute chain length, loading as well as gra...

2011-01-01

366

Noninvasive prediction of vertebral body compressive strength using nonlinear finite element method and an image based technique  

British Library Electronic Table of Contents (United Kingdom)

Noninvasive prediction of vertebral body strength under compressive loading condition is a valuable tool for the assessment of clinical fractures. This paper presents an effective specimen-specific approach for noninvasive prediction of human vertebral strength using a nonlinear finite element (FE) model and an image based parameter based on the quantitative computed tomography (QCT). Nine thoracolumbar vertebrae excised from three cadavers with an average age of 42 years old were used as the samples. The samples were scanned using the QCT. Then, a segmentation technique was performed on each QCT sectional image. The segmented images were then converted into three-dimensional FE models for linear and nonlinear analyses. A new material model was implemented in our nonlinear model being more...

2010-01-01

367

Irreversible Performance of a Quantum Harmonic Heat Engine  

CERN Document Server

The unavoidable irreversible losses of power in a heat engine are found to be of quantum origin. Following thermodynamic tradition a model quantum heat engine operating by the Otto cycle is analyzed. The working medium of the model is composed of an ensemble of harmonic oscillators. A link is established between the quantum observables and thermodynamical variables based on the concept of canonical invariance. These quantum variables are sufficient to determine the state of the system and with it all thermodynamical variables. Conditions for optimal work, power and entropy production show that maximum power is a compromise between the quasistatic limit of adiabatic following on the compression and expansion branches and a sudden limit of very short time allocation to these branches. At high temperatures and quasistatic operating conditions the efficiency at maximum power coincides with the endoreversible result. The optimal compression ratio ...

2006-01-01

368

Interplay of the chirps and chirped pulse compression in a high-gain seeded free-electron laser  

International Nuclear Information System (INIS)

In a seeded high-gain free-electron laser (FEL), where a coherent laser pulse interacts with an ultrarelativistic electron beam, the seed laser pulse can be frequency chirped, and the electron beam can be energy chirped. Besides these two chirps, the FEL interaction introduces an intrinsic frequency chirp in the FEL even if the above-mentioned two chirps are absent. We examine the interplay of these three chirps. The problem is formulated as an initial value problem and solved via a Green function approach. Besides the chirp evolution, we also give analytical expressions for the pulse duration and bandwidth of the FEL, which remains fully longitudinally coherent in the high-gain exponential growth regime. Because the chirps are normally introduced for a final compression of the FEL pulse, some conceptual issues are discussed. We show that to get a short pulse duration, an energy chirp in the electron beam is important.

2007-03-01

369

Internal strain and texture evolution during deformation twinning in magnesium  

Energy Technology Data Exchange (ETDEWEB)

The development of a twinned microstructure in hexagonal close-packed rolled magnesium compressed in the in-plane direction has been monitored in situ with neutron diffraction. The continuous conversion of the parent to daughter microstructure is tracked through the variation of diffraction peak intensities corresponding to each. Approximately 80% of the parent microstructure twins by 8% compression. Elastic lattice strain measurements indicate that the stress in the newly formed twins (daughters) is relaxed relative to the stress field in the surrounding matrix. However, since the daughters are in a plastically 'hard' deformation orientation, they quickly accumulate elastic strain as surrounding grains deform plastically. Polycrystal modeling of the deformation process provides insight about the crystallographic deformation mechanism involved.

2005-06-15

370

Infrared (IR) vs x-ray power generation in the SLAC Linac Coherent Light Source (LCLS)  

Energy Technology Data Exchange (ETDEWEB)

The LCLS, a Free-Electron Laser (FEL) designed for operation at a first harmonic energy of 300 eV ({lambda} {congruent} 40{Angstrom}) in the Self-Amplified Spontaneous Emission (SASE) regime, will utilize electron bunches compressed down to durations of <0.5ps, or lengths of <150 {mu}. It is natural to inquire whether coherent radiation of this (and longer) wavelength will constitute a significant component of the total coherent output of the FEL. In this paper a determination of a simple upper bound on the IR that can be generated by the compressed bunches is outlines. Under the assumed operating parameters of the LCLS undulator, it is shown that that IR component of the coherent output should be strongly dominated by the x-ray component.

1993-05-01

371

In situ strain measurements during the formation of palladium silicide films  

Energy Technology Data Exchange (ETDEWEB)

The evolution of strain in the Pd-Si system during the growth of Pd{sub 2}Si thin films on Si (100) substrate has been followed in situ using a double optical beam technique. As was observed for the Pt-Si system, the reaction to form Pd{sub 2}Si yields a compressive intrinsic surface film stress as well as for the silicon-rich suicides as proposed by Angilello et al. [Thin Film Interfaces and Interactions, edited by J. Baglin and J. Poate (The Electrochemical Society, Pennington, NJ, 1980)]. A transmission electron microscopy analysis has revealed grain growth during the formation of Pd{sub 2}Si which cannot account for the compressive film stresses. The formation of silicide at the interfaces rather than the overall change in volume agrees with the sign of the stresses formed. 29 refs., 4 figs., 3 tabs.

1993-03-01

372

Improved batch fuzzy learning vector quantization for image compression  

British Library Electronic Table of Contents (United Kingdom)

In this paper, we develop a batch fuzzy learning vector quantization algorithm that attempts to solve certain problems related to the implementation of fuzzy clustering in image compression. The algorithm's structure encompasses two basic components. First, a modified objective function of the fuzzy c-means method is reformulated and then is minimized by means of an iterative gradient-descent procedure. Second, the overall training procedure is equipped with a systematic strategy for the transition from fuzzy mode, where each training vector is assigned to more than one codebook vectors, to crisp mode, where each training vector is assigned to only one codebook vector. The algorithm is fast and easy to implement. Finally, the simulation results show that the method is efficient and appears...

2008-01-01

373

Ignition delay as determined in a variable-compression ratio direct-injection diesel engine  

Energy Technology Data Exchange (ETDEWEB)

A variable-compression ratio, direct-injection diesel engine (VCR) has been designed and assembled at Southwest Research Institute with the intention of examining the current procedures for rating the ignition quality of diesel fuels and the meaning of ignition delay as an indicator of ignition and combustion quality. Using a slightly modified ASTM D 613 procedure, the engine has been used to rate the ignition quality of 43 different test fuels. The ratings obtained in the VCR engine are compared to the corresponding rating obtained using the standard cetane rating procedure. Some of the problems associated with the standard procedure became apparent during these experiments. The experimental results are discussed in terms of the problems and the advantages of a proposed VCR-based rating procedure.

1987-01-01

374

Fragile granular jamming  

Energy Technology Data Exchange (ETDEWEB)

We demonstrate experimentally that the route to a jammed state for a set of bi-dispersed frictional disks, subjected to uni-axial compression from a random initial unjammed state, consists of a consolidation state, a fragile jammed state, and finally a rigid jammed state. In the consolidation regime, the pressure on the sides increases very slowly with the packing fraction {phi} and there are no detectable stress chains. In the fragile jammed state, stress chains are visible, the pressure increases exponentially with {phi}, and the fraction of moving disks drops exponentially. Eventually, a final regime where particle displacements are below our resolution and the pressure varies approximately linearly with {phi} is reached. We argue that this scenario is generic for ather mal frictional compressed particles.

2009-01-01

375

Effective thermal conductivity and thermal contact resistance of gas diffusion layers in proton exchange membrane fuel cells. Part 1: Effect of compressive load  

British Library Electronic Table of Contents (United Kingdom)

Heat transfer through the gas diffusion layer (GDL) is a key process in the design and operation of a PEM fuel cell. The analysis of this process requires determination of the effective thermal conductivity as well as the thermal contact resistance associated with the interface between the GDL and adjacent surfaces/layers. In the present study, a custom-made test bed that allows the separation of effective thermal conductivity and thermal contact resistance in GDLs under vacuum and ambient conditions is described. Measurements under varying compressive loads are performed using Toray carbon paper samples with a porosity of 78% for a range of thicknesses. The measurements are complemented by compact analytical models that achieve good agreement with experimental data. A key finding is that ...

2011-01-01

376

Development of Ultra-Fast Silicon Switches for Active X-Band High Power RF Compression Systems  

Energy Technology Data Exchange (ETDEWEB)

We present the recent results of our research on the high power ultra-fast silicon RF switches. This switch is composed of a group of PIN diodes on a high purity silicon wafer. The wafer is inserted into a cylindrical waveguide under TE{sub 01} mode, performing switching by injecting carriers into the bulk silicon. Our current design uses a CMOS compatible process and the device was fabricated at SNF (Stanford Nanofabrication Facility). 300 ns switching time has been observed, while the switching speed can be improved further with 3-D device structure and faster driving circuit. Power handling capacity of the switch is at the level of 10 MW. The switch was designed for active X-band RF pulse compression systems--especially for NLC, but it is also possible to be modified for other applications and other frequencies.

2006-03-06

377

Coolside Waste Management Research quarterly technical progress report, January 1, 1993--March 31, 1993  

Energy Technology Data Exchange (ETDEWEB)

This project seeks to produce sufficient information on the physical and chemical nature of Coolside waste to design and construct physically stable and environmentally safe landfills. Unconfined compressive strength and permeability tests are reported on samples remolded near 90, 95, and 100% of low energy, standard, and modified dry densities. Unconfined compressive strength tests were also performed on some of the samples after permeability tests were completed. Swell tests were initiated on samples from Coolside pilot plant run {number_sign}2 and on a FBC hydrated ash remolded near 95% of standard density and optimum moisture content.

1993-11-01

378

Compression molded energy storage flywheels  

Energy Technology Data Exchange (ETDEWEB)

Flywheels containing fiber-reinforced composite materials have attributes suitable for vehicular propulsion, indicating the need for rotor designs which are easily manufactured and low in cost. This development goal was pursued in a cooperative effort between Owens-Corning Fiberglas and Lawrence Livermore Laboratory which investigated flywheels made from compression-molded sheet molding compound (SMC). The design resulted from a Lawrence Livermore analysis, with successful fabrication achieved using a procedure developed by Owens-Corning. Details concerning materials selection, rotor fabrication, and testing are discussed. Owens-Corning subsequently initiated a technical/marketing survey to determine current industrial interests in a low-cost flywheel design; precursory information, pertaining to composite flywheels in particular, is described.

1982-08-01

379

Comparison of the Influence of Temperature on the High-Strain-Rate Mechanical Responses of PBX 9501 and EDC37  

British Library Electronic Table of Contents (United Kingdom)

Many high-strain-rate compression measurements (2000 per second) using a specially designed split Hopkinson pressure bar (SHPB) for the plastic-bonded explosive PBX9501 have been reported in the literature, but there is a sparsity of data for a United Kingdom polymer-bonded explosives (PBX) known as EDC37. Both EDC37 and PBX9501 are cyclotetramethylenetetranitramine-based (HMX-based) PBXs with high filler contents. The binder systems for the PBXs are very different: EDC37 consists of a nitroplasticized nitrocellulose and PBX9501 a nitroplasticized ESTANE. PBX9501 exhibits nearly invariant fracture strains of ?1.5?pct as a function of temperature at high strain rates, whereas EDC37 fails at ?2 to 2.5?pct. The maximum compressive strengths for both PBXs were measured at 150?Mpa at ?55??C, bu...

2008-01-01

380

Combustion of jojoba methyl ester in an indirect injection diesel engine  

Energy Technology Data Exchange (ETDEWEB)

An experimental investigation has been carried out to examine for the first time the performance and combustion noise of an indirect injection diesel engine running with new fuel derived from pure jojoba oil, jojoba methyl ester, and its blends with gas oil. A Ricardo E6 compression swirl diesel engine was fully instrumented for the measurement of combustion pressure and its rise rate and other operating parameters. Test parameters included the percentage of jojoba methyl ester in the blend, engine speed, load, injection timing and engine compression ratio. Results showed that the new fuel derived from jojoba is generally comparable and a good replacement to gas oil in diesel engine at most engine operating conditions, in terms of performance parameters and combustion noise produced. (author)

2003-07-01

381

Chemistry between crosslinks affects the properties of peptide hydrogels  

British Library Electronic Table of Contents (United Kingdom)

Protein hydrogels were prepared by substituting ovalbumin with different concentrations of ethyl vinyl sulfone (EVS) or acrylic acid (AA) and crosslinking with divinyl sulfone (DVS). Fourier transform-infrared (FT-IR) spectroscopic studies confirmed the addition of EVS, AA, and DVS onto the protein. Swelling was assessed as a function of pH in the range of 2.5 to 9.4 and ionic strength. The elastic modulus of the gels was determined in shear and compression. Stress relaxation was assessed in compression. The substituent highly affected swelling and modulus with both hydrogels displaying non-Gaussian behavior in the range of hydrogel environments studied. Acrylic acid substituted ovalbumin exhibited a decreasing modulus with increasing swelling behaving as a polyelectrolyte with low added s...

2011-01-01

382

Visualization of direct contact heat transfer between water and molten alloy  

Energy Technology Data Exchange (ETDEWEB)

We have been developing an innovative Steam Generator concept of Fast Breeder Reactors by using liquid-liquid direct contact heat transfer. In this concept, the SG shell is filled with a molten alloys, which is heated by primary sodium. Water is fed into the high temperature molten alloy, and evaporates by direct contact heating. In order to obtain the fundamental information to discuss the heat transfer mechanisms of the direct contact between the water and the alloy, this phenomenon was visualized by real-time neutron radiography. JRR-3M real-time thermal neutron radiography in Japan Atomic Energy Research Institute was used. Followings are main results. (1) The vigorous evaporation occurs in the molten alloy. This phenomena is different from the known phenomenon such as the evaporation of refrigerant R-113 in the water. (2) The evaporation in the bubble has finished in a moment due to high heat transfer performance between the liquid and molten alloy. (3) It is ...

1996-06-01

383

Upgrade of X-ray Magnetic Diffraction Experimental System and Its Application to Ferromagnetic Material  

International Nuclear Information System (INIS)

We have performed X-ray magnetic diffraction (XMD) experiment of ferromagnets at the Photon Factory (PF) of the High Energy Accelerator Research Organization (KEK) in Tsukuba. In this study, we have upgraded the XMD experimental system in order to apply this method to as many samples as possible. Upgrade was made for (1) the X-ray counting system and related measurement program, (2) the electromagnet, and (3) the refrigerator. The performance of the system was enhanced so that (1) the counting rate capability was improved from 104cps to 105cps, (2) the maximum magnetic field was increased from 0.85T to 2.15T, and (3) the lowest sample temperature was reduced from 15K to 5K. The new system was applied to an orbital ordering compound of YTiO3, and we obtained spin magnetic form factor for the reflection plane (010) perpendicular to the b axis. The magnetic field of 2T was needed to saturate the magnetization of YTiO3 along the b axis. These are the first data with ...

2007-01-19

384

USE OF A CONTROLLED CHLORINE DIOXIDE (CLO2) RELEASE SYSTEM IN COMBINATION WITH MODIFIED ATMOSPHERE PACKAGING (MAP) TO CONTROL THE GROWTH OF PATHOGENS  

British Library Electronic Table of Contents (United Kingdom)

Abstract Salmonella Typhimurium and Listeria monocytogenes are major bacterial pathogens associated with poultry products. A controlled released ClO2 sachet applied with modified atmosphere packaging (MAP) was evaluated for its ability to control the growth of S. Typhimurium and L. monocytogenes on raw chicken breast during refrigerated storage. The fresh chicken samples were inoculated with one or the other of the pathogens at 104-cfu/g, and the packages (with and without ClO2 sachet) were flushed with ambient air or 30% CO2/70% N2 before sealing, and then stored at 4C for up to 21 days. The maximum reduction in MAP plus ClO2 (compared with MAP alone) was 0.68-log-cfu/g for S. Typhimurium and 1.87-log-cfu/g for L. monocytogenes. Color and pH changes of the chicken breast were observed at ...

2011-01-01

385

Two-fluid modeling of condensation in the presence of noncondensables in two-phase channel flows  

Energy Technology Data Exchange (ETDEWEB)

Condensing two-phase channel flow occurs in many industrial applications, including heating and refrigeration systems. It can also occur in certain nuclear reactor accidents. For example, during a small-break loss-of-coolant accident in a pressurized water reactor, following the partial depletion of the primary coolant, condensation of steam on the primary side of the steam generator tubes can provide a heat sink for disposal of the decay heat generated in the reactor core. Condensing two-phase flow can also play an important role in the operation of the passive emergency cooling system in the advanced simplified boiling water reactor. Here, steady-state condensation in the presence of a noncondensable in a concurrent two-phase channel flow is analyzed using a two-fluid model. The effect of noncondensables on the combined heat transfer at the liquid-gas mixture interphase is accounted for by using the stagnant film model, and closure relations relevant to the ...

1995-01-01

386

Time-Resolved Aerosol Collector for CCSEM/EDX Single Particle Analysis  

Energy Technology Data Exchange (ETDEWEB)

An automated Time Resolved Aerosol Collector (TRAC) has been developed for sequential sampling of field-collected aerosols for laboratory-based Computer Controlled Scanning Electron Microscopy/Energy Dispersed X-ray (CCSEM/EDX) single particle analysis. The collector is optimized for use of grid-supported 20 nm carbon films as deposition substrates. The carbon films have low enough X-ray background to permit EDX analysis down to 0.1-0.2 ?m particles, including detection of low-Z elements: C, N, & O. The TRAC provides unattended sampling onto a set of 151 individual grids, at sequential time intervals as short as 1 min. After collection, the samples are sealed and refrigerated pending analysis. The utility of the TRAC-CCSEM/EDX approach is exemplified using the aerosol samples collected during the Texas 2000 Air Quality Studies (Aug. 15 ? Sept. 15, 2000). We are able to quantitatively follow the time evolution in the relative contribution of non-volatile ...

2003-01-02

387

The national plan of fight against greenhouse effect; Le plan national de lutte contre l'effet de serre  

Energy Technology Data Exchange (ETDEWEB)

France has committed herself to keep in 2010 the same levels of greenhouse gas emissions as those of 1990, i.e. 144 millions of tons of carbon equivalent (MtCe). However, taking into account the existing pollution abatement measures and the measurements performed so far, the greenhouse gases level should reach 160 MtCe in 2010. Therefore, the inter-ministry commission on greenhouse effect decided on November 27, 1998 to elaborate a new national plan of fight against greenhouse effect. The elaboration of the new plan has fallen under the responsibility of the inter-ministry mission of greenhouse effect (MIES). The new plan was presented by the prime minister, L. Jospin, on January 19, 2000. This document summarises the content of the new plan: architecture (modalities of elaboration, content), measures for the reduction of greenhouse gas emissions (industry, transportation sector, buildings, agriculture-forestry, wastes valorization, development of renewable energies, ...

2000-07-01

388

The Schenberg spherical antenna: status report  

International Nuclear Information System (INIS)

Full text. Here we present a status report of the Schenberg antenna, which started commissioning runs in September 2006 under the full support of FAPESP. In its first commissioning runs we tested three preliminary parametric transducer systems, which did not achieve a high enough performance for placing the antenna sensitivity in the range of the calibrator capacitor. Instead of improving the calibrator, making it capable of introducing a larger input force, we decided to go to a radical upgrading operation: replacing the three transducers for a complete set of six transducers, with better sensitivity and arranged according to the truncated icosahedron configuration, plus two extra ones; starting to install the dilution refrigerator; installing wires, cables, and amplifiers for the complete set of transducer circuits; and a new suspension and vibration isolation system for the cabling and microstrip antennas. We also have been developing a new set of transducers, ...

2009-09-14

389

System suitable for use in neutron radiography  

Energy Technology Data Exchange (ETDEWEB)

A system for real-time neutron radiography of moving objects is described. It comprise a source adapted to generate a continuous uninterrupted series of neutron pulses. Each pulse has a predetermined peak power and duration compatible with the framing times of a real-time video imaging system. A transporter moves an object to be examined to bring sequentially position selected portions of the object in the path of the pulses. Where the object itself has moving components, pulses are sequentially incident on the object. According to any dissimilarities, the object will alter the intensity of the neutrons passing therethrough. In order to record separately the changes in the neutron intensity, for each pulse, an imager is positioned to receive the neutron beam pulses which have been altered by their passage through the object and produce images indicating intensity alterations. A refrigerated beryllium filter can be used to effectively eliminate thermal neutrons from ...

1990-02-07

390

System suitable for use in neutron radiography  

International Nuclear Information System (INIS)

A system for real-time neutron radiography of moving objects is described. It comprise a source adapted to generate a continuous uninterrupted series of neutron pulses. Each pulse has a predetermined peak power and duration compatible with the framing times of a real-time video imaging system. A transporter moves an object to be examined to bring sequentially position selected portions of the object in the path of the pulses. Where the object itself has moving components, pulses are sequentially incident on the object. According to any dissimilarities, the object will alter the intensity of the neutrons passing therethrough. In order to record separately the changes in the neutron intensity, for each pulse, an imager is positioned to receive the neutron beam pulses which have been altered by their passage through the object and produce images indicating intensity alterations. A refrigerated beryllium filter can be used to effectively eliminate thermal neutrons from ...

1988-07-20

391

Synchrotron resource of the Howard Hughes Medical Institute  

Energy Technology Data Exchange (ETDEWEB)

The Synchrotron Resource of the Howard Hughes Medical Institute will be dedicated to structural analyses of biological macromolecules, primarily through crystallography. This facility is under construction at the X4 port of the National Synchrotron Light Source at Brookhaven National Laboratory, and it will comprise three beamlines. The first line to be built has been devised to apply the multiwavelength anomalous diffraction method which provides direct estimates for the phases of reflections. The second line will be devoted to rapid and essentially routine diffraction measurements, mainly through the rotation method. These two experimental stations are contained within refrigerated radiation enclosures that will maintain clean environments, narrowly defined constant temperatures, and protection against biohazard at biosafety level BL-2. At the same time as the second line will be developed, the swath center is planned to first serve as a monitor of the white ...

1989-07-01

392

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 cost compared with the latter. A case where the operating cost of the resolving method was sometimes larger than the proposed method was due to ...

1996-02-01

393

Resistive cryogenic cable economic-viability evaluation. Final report, Volume I  

Energy Technology Data Exchange (ETDEWEB)

This report presents a reassessment of the design of Resistive Cryogenic Cable Systems with regard to dielectric material selection, thermal insulation selection, conductor design, and refrigeration subsystem design. An algorithm using test data generated as part of the program and available from the literature was developed and used to assess the driving parameters for system cost analysis. The results of this cost sensitivity analysis are presented. An electric utility, Public Service Electric and Gas of New Jersey (PSE and G), performed an economic viability evaluation comparing two selected Resistive Cryogenic Cable Systems to a conventional cable system (high pressure oil-filled). The comparison was made for a 35-mile network application on the PSE and G transmission system scheduled to be placed in service in 1995. Consideration was given to equipment capital, installation, and operating costs. It was concluded that a Multilayer Vacuum Insulated Resistive ...

1980-03-31

394

Pumps and compressors - buyers` guide 1996/`97; Pumpen und Kompressoren - Einkaufsfuehrer 1996/97  

Energy Technology Data Exchange (ETDEWEB)

The 1996/`97 buyers` guide comprises ten chapters: 1. List of suppliers; 2. Waste management, effluents, sewage systems; 3. Water supply, hydroengineering; 4. Chemistry, petrochemistry; 5. Chemical engineering; 6. Food industry, biotechnology; 7. Paper and cellulose industry; 8. Natural gas industry, natural gas supply; 9. Power plant engineering, power systems, district heating; 10. Air conditioning and refrigeration engineering. (orig.) [Deutsch] Der vorliegende Einkaufsfuehrer 1996/97 ist in zehn Kapiteln gegliedert. Diese sind: 1. Firmenverzeichnis 2-11 2. Entsorgungs-/Abwassertechnik, Klaeranlagen 12-15 3. Wasserversorgung, Wassertechnik 16-18 4. Chemie, Petrochemie 19-22 5. Verfahrenstechnik 23-26 6. Lebensmittelindustrie, Biotechnik 27-29 7. Papier-, Zeluloseindustrie 30-31 8. Erdgasindustrie, -versorgung 32 9. Kraftwerkstechnik, Energieanlagen, Fernwaerme 33-34 10. Kaelte-/Klimatechnik 35-36. (orig.)

1996-12-01

395

Irradiation of spices, packaging materials and luncheon to improve the storability of the end product  

International Nuclear Information System (INIS)

Spices and packaging materials were exposed to gamma irradiation at a dose of 10 KGy. Luncheon was prepared with irradiated or non-irradiated spices. Prepared luncheon was packaged in irradiated or non-irradiated packaging materials. Packaged luncheon was treated with 2 KGy. Treated and untreated packaged luncheon were kept in a refrigerator (1-4 Centigrade) for 12 months. Microbiological, nutritive and chemical characteristics of luncheon were evaluated after processing and during storage; whereas, sensory quality was evaluated only after irradiation. Gamma irradiation decreased the microorganisms counts of spices, packaging materials and packed luncheon and increased the shelf-life of packaged luncheon products. No major differences in moisture, protein, fat, ph value, total acidity, lipid peroxide and volatile basic nitrogen were observed due to irradiation. Sensory evaluation showed that all the combination treated luncheon were acceptable regarding sensory ...

396

Integration and Testing of the Micro-X Rocket Payload  

Science.gov (United States)

The Micro-X instrument is a rocket borne, X-ray imaging spectrometer planned for launch in October 2011. An array of 128 Transition Edge Sensors (TESs) on a 600 micron pitch will observe incoming photons in the 0.2-3 keV energy band with an energy resolution of 2-4 eV at 1 keV. X-rays will be focused onto the TES array by a conically approximated Wolter optic with an effective area of 300 cm^2 giving the instrument a field of view of 11.8 arcmin. This performance will constitute a substantial improvement over current non-dispersive detectors for X-ray spectroscopy of extended sources and will be the first demonstration of a TES-based microcalorimeter in space. The TESs will utilize the 50 mK stage of an Adiabatic Demagnetization Refrigerator (ADR) as a heat bath, and will be read out by a SQUID time division multiplexer. The first flight of the Micro-X instrument will observe the Puppis A supernova remnant. Future targets include the core of the Virgo cluster and ...

2011-05-01

397

Influence of gamma irradiation and storage on the microbial load, chemical and sensory quality of chicken kabab  

Energy Technology Data Exchange (ETDEWEB)

Influence of gamma irradiation and storage on the microbial load, chemical and sensory quality of chicken kabab was investigated. Chicken kabab was treated with 0, 2, 4 or 6 kGy doses of gamma irradiation. Treated and untreated samples were kept in a refrigerator (1-4 deg. C). Microbiological, chemical and sensory characteristics of chicken kabab were evaluated at 0-5 months of storage. Gamma irradiation decreased the microbial load and increased the shelf-life of chicken kabab. Irradiation did not influence the major constituents of chicken kabab (moisture, protein and fats). No significant differences (p>0.05) were observed for total acidity between non-irradiated (control) and irradiated chicken kabab. Thiobarbitric acid (TBA) values (expressed as mg malonaldehyde (MDA)/kg chicken kabab) and volatile basic nitrogen (VBN) in chicken kabab were not affected by the irradiation. Sensory evaluation showed no significant differences between irradiated and ...

2010-08-15

398

High-efficiency pump for space helium transfer. Final Technical Report  

Energy Technology Data Exchange (ETDEWEB)

A centrifugal pump was developed for the efficient and reliable transfer of liquid helium in space. The pump can be used to refill cryostats on orbiting satellites which use liquid helium for refrigeration at extremely low temperatures. The pump meets the head and flow requirements of on-orbit helium transfer: a flow rate of 800 L/hr at a head of 128 J/kg. The overall pump efficiency at the design point is 0.45. The design head and flow requirements are met with zero net positive suction head, which is the condition in an orbiting helium supply Dewar. The mass transfer efficiency calculated for a space transfer operation is 0.99. Steel ball bearings are used with gas fiber-reinforced teflon retainers to provide solid lubrication. These bearings have demonstrated the longest life in liquid helium endurance tests under simulated pumping conditions. Technology developed in the project also has application for liquid helium circulation in terrestrial facilities and for ...

1991-12-01

399

Effects of microwaves on cell survival at elevated temperatures  

Energy Technology Data Exchange (ETDEWEB)

Since microwaves are used in human cancer therapy, information on specific biological effects of microwaves at elevated temperatures is important. To help supply this information, we exposed mammalian cells (CHO) and bacteria (Serratia marcescens) to hyperthermal temperatures (43, 44, and 45/sup o/C for CHO and 48, 49, and 50/sup o/C for the bacteria) with and without microwave irradiation. Temperature control was maintained by a refrigeration-reheat system and high-velocity water recirculation. The 2450-MHz microwave source was operated in a pulsed mode with power density up to 500 mW/cm/sup 2/. As expected, the survival curve slopes for both cell types increased rapidly with temperature, doubling for each degree Celsius. Microwave irradiation produced no significant change in extrapolation number for either cell type. However, survival curves of CHO cells which received microwaves were steeper by a factor of 1.25 than their sham-irradiated controls. No ...

1981-12-01

400

Development and Application of Subchannel Analysis Code Technology for Advanced Reactor Systems  

Energy Technology Data Exchange (ETDEWEB)

A study has been performed for the development and assessment of a subchannel analysis code which is purposed to be used for the analysis of advanced reactor conditions with various configurations of reactor core and several kinds of reactor coolant fluids. The subchannel analysis code was developed on the basis of MATRA code which is being developed at KAERI. A GUI (Graphic User Interface) system was adopted in order to reduce input error and to enhance user convenience. The subchannel code was complemented in the property calculation modules by including various fluids such as heavy liquid metal, gas, refrigerant,and supercritical water. The subchannel code was applied to calculate the local thermal hydraulic conditions inside the non-square test bundles which was employed for the analysis of CHF. The applicability of the subchannel code was evaluated for a high temperature gas cooled reactor condition and supercritical pressure conditions with water and Freon. A ...

2006-01-15

401

Analyses of mixed-hydrocarbon binary thermodynamic cycles for moderate-temperature geothermal resources  

Energy Technology Data Exchange (ETDEWEB)

A number of binary geothermal cycles utilizing mixed hydrocarbon working fluids were analyzed with the overall objective of finding a working fluid which can produce low-cost electrical energy using a moderately-low temperature geothermal resource. Both boiling and supercritical shell-and-tube cycles were considered. The performance of a dual-boiling isobutane cycle supplied by a 280/sup 0/F hydrothermal resource (corresponding to the 5 MW pilot plant at the Raft River site in Idaho) was selected as a reference. To investigate the effect of resource temperature on the choice of working fluid, several analyses were conducted for a 360/sup 0/F hydrothermal resource, which is representative of the Heber resource in California. The hydrocarbon working fluids analyzed included methane, ethane, propane, isobutane, isopentane, hexane, heptane, and mixtures of those pure hydrocarbons. For comparison, two fluorocarbon refrigerants were also analyzed. These fluorocarbons, ...

1981-02-01

402

An investigation into flow regimes for two-phase helium flow  

Energy Technology Data Exchange (ETDEWEB)

The Tevatron accelerator at Fermilab incorporates long two-phase helium passages. During magnet design, the generalized flow map of Baker was used to predict homogeneous flow. Longer than expected magnet time constants led to this investigation. The importance of predicting the flow regime has been amplified with the advent of non-horizontal accelerator designs. A test setup was constructed at Fermilab to investigate two-phase helium flow regimes for conditions practical in accelerator designs. The setup consisted of a standard Tevatron satellite refrigerator, subcooling dewar, heater, 35 m long transfer line, and a specialized end box. A knife blade on the midplane of the transfer line diverted the flow from the upper and lower halves of the pipe to separate vessels in the end box. The amount of liquid above and below the plane was measured at various total mass flow rates and liquid percentages. The results show that stratified flow occurs at much higher liquid ...

1987-10-01

403

Activity of Citrus Essential Oils against-Escherichia coli-O157:H7 and-Salmonella-spp. and Effects on Beef Subprimal Cuts under Refrigeration  

British Library Electronic Table of Contents (United Kingdom)

Abstract:- Escherichia coli-O157:H7 and-Salmonella-spp. are bacterial pathogens often associated with beef, and cause many cases of foodborne illness each year in the United States. During beef slaughter and processing, these bacteria may spread from the hide or intestines to the carcass. The objective of this research was to investigate the use of naturally occurring compounds citrus essential oils (CEOs) extracted from orange peel to reduce or eliminate these pathogens at the chilling stage of processing, or during fabrication. Brisket flats (used to simulate beef subprimals) were spot inoculated with approximately 6 log of surrogate generic-E. coli-cocktail (previously shown to be identical in growth and survival parameters to-E. coli-O157:H7 and-Salmonella-spp.). Following drying, CEOs...

2011-01-01

404

Use of the acoustic method for checking the quality of concrete of hydroelectric and pumped storage stations  

Energy Technology Data Exchange (ETDEWEB)

This article describes acoustic methods used in the in-service inspection of the dams and peripheral concrete structures of the Toktogul, Kurpsai, and Bratsk hydroelectric and pumped storage plants. The tests were conducted to assess the compression strength, elasticity, and tensile strength of the concretes. Comparative evaluations against drill core studies proved the acoustic methods to be sufficiently accurate in predicting aging behavior and loss of mechanical and physical integrity in the concretes.

1987-09-01

405

The Percus-Yevick theory is alive and well  

Science.gov (United States)

The pressure of a 6:12 fluid is obtained from the Percus-Yevick theory at the temperature kT/? = 1.35. The energy equation results are in excellent agreement with machine calculation results in contrast to the pressure and compressibility equation results. Present address: Diffusion Research Unit, The Australian National University, Canberra, ACT, Australia.

1970-01-01

406

Structure of an accelerator island with one step on double period of conserving area mapping  

International Nuclear Information System (INIS)

The structure of the P-2, S-1 accelerator mode with one step, S-1, on double period, P-2 for systems, described by the Harper mapping as well as by standard mapping, is analyzed. Detailed analysis of stability criteria is given and comparison with the results of numerical analysis is performed. Three-period compression of the P-2, S-1 island is revealed in the standard mapping. Refs. 7, figs. 7.

407

Review of combustion processes in the dual fuel engine: the gas diesel engine  

Energy Technology Data Exchange (ETDEWEB)

This review examines the characteristics of the compression-ignition type of dual-fuel engine and the combustion phenomena that affect these characteristics. The specific areas covered involve normal combustion processes, the nature and origin of engine knock, operation with LNG, and the effect of intake temperature on combustion efficiency and exhaust composition.

1980-01-01

408

Preparation of pinewood/polymer/composites using gamma irradiation  

Energy Technology Data Exchange (ETDEWEB)

Wood/polymer composites (WPC) have been prepared from pinewood with different compounds using gamma irradiation: butyl acrylate, butyl methacrylate, styrene, acrylamide, acrylonitrile, and unsaturated polyester styrene resin. The polymer loading was determined with respect to the compound concentration and the irradiation dose. The polymer loading increases generally with increase in the monomer or polymer concentration. Tensile and compression strength have been improved in the four cases, but no improvement was observed using unsaturated polyester styrene resin or acrylamide.

2006-09-15

409

Novel injectable and in situ curable glycolide/lactide based biodegradable polymer resins and composites.  

Science.gov (United States)

Novel in situ polymerizable liquid three-arm biodegradable oligomeric polyesters based upon glycolic acid (GA), L-lactic acid (LLA), and their copolymers are synthesized and characterized. Injectable and in situ curable polymer neat resins and their composites formulated with bioabsorbable beta-tricalcium phosphate are prepared at room temperature using photo- and redox-initiation systems, respectively. The cured neat resins show the initial compressive yield strength (YCS, MPa), modulus (M, MPa), ultimate compressive strength (UCS, MPa), and toughness (T, kN mm), ranging from 4.0 to 20.1, 201.5 to 730.2, 82.7 to 310.5, and 1.02 to 3.93. The cured composites show the initial YCS, M, UCS and T, ranging from 27.7 to 56.4, 1440 to 4870, 81.6 to 158.9, and 0.94 to 1.97. Increasing GA/LLA ratio increases all the initial compressive strengths of both neat resins and composites. Increasing filler content increases YCS and M but ...

2006-08-18

410

Monolithic stabilized Yb-fiber All-PM laser directly delivering nJ-level femtosecond pulses  

DEFF Research Database (Denmark)

We present a monolithic, self-starting, all-PM, stabilized Yb-fiber laser, pulse-compressed in a hollow-core PM photonic crystal fiber, providing the 370 fs pulses of 4 nJ energy with high mode quality.

2008-01-01

411

Metastatic Ewing's sarcoma to the skull: CNS involvement excluded by MRI  

International Nuclear Information System (INIS)

A case of metastatic Ewing's sarcoma to the skull is presented, demonstrating the superiority of magnetic resonance imaging over other imaging modalities to exclude CNS involvement. Precise delineation of different tumor components in extradural location contained in an intact dural rim together with compressed cortex showing no signs of tumorous involvement constituted an MRI appearance allowing us to exclude tumor outgrowth into the brain. (orig.).

412

Mathematical two-dimensional model for three-phase filtering of compressible fluids  

Energy Technology Data Exchange (ETDEWEB)

A mathematical model is proposed for three-phase filtering which is a particular case of a more general model of filtering multiple component mixtures and makes it possible to describe three-phase filtering flows under conditions where the pressure of saturation is variable in time and in space. In the proposed model, the system of unknown functions is selected so that it makes it possible to trace fairly simply the pressure of saturation and to compute the corresponding equation coefficients.

1982-01-01

413

Lattice parameters and thermal expansion of solid ortho-deuterium  

Energy Technology Data Exchange (ETDEWEB)

X-ray results on the lattice parameters, molar volume and thermal expansion coefficients of solid ortho-deuterium for the region from 2 K to the melting point are reported. It is found that the thermal expansion of ortho-deuterium crystals, similarly to parahydrogen is essentially anisotropic near the melting temperature. The vacancy density at the triple point is estimated. Some thermodynamic characteristics of ortho-deuterium are calculated and temperature dependences of heat capacity at constant volume, isothermal compressibility and Gruneisen constant are analyzed.

1984-01-01

414

In-Use Performance Comparison of Hybrid Electric, CNG, and Diesel Buses at New York City Transit  

Energy Technology Data Exchange (ETDEWEB)

The National Renewable Energy Laboratory (NREL) evaluated the performance of diesel, compressed natural gas (CNG), and hybrid electric (equipped with BAE Systems? HybriDrive propulsion system) transit buses at New York City Transit (NYCT). CNG, Gen I and Gen II hybrid electric propulsion systems were compared on fuel economy, maintenance and operating costs per mile, and reliability.

2008-06-01

415

Examination of compression and resilience characteristics of fibrous insulation blankets  

International Nuclear Information System (INIS)

Load-deflection characteristics of alumina and alumino-silicate fibrous blankets were experimentally determined. Load retention and springback capability of combinations of these materials were measured in a 10,000-hour test at surface temperatures of 650 to 1000"0C (1200 to 1832"0F). Experimental results are presented and future testing plans are discussed.

416

Electronic and geometric structure of transition-metal nanoclusters  

Energy Technology Data Exchange (ETDEWEB)

A massively-parallel ab initio computer code, which uses Gaussian bases, pseudopotentials, and the local density approximation, permits the study of transition-metal systems with literally hundreds of atoms. We present total energies and relaxed geometries for Ru, Pd, and Ag clusters with N = 55, 135, and 140 atoms; we also used the DMOL code to study 13-atom Pd and Cu clusters, with and without hydrogen. The N = 55 and 135 clusters were chosen because of simultaneous cubo-octahedral (fcc) and icosahedral (icos) sub-shell closings, and we find icos geometries are preferred. Remarkably large compressions of the central atoms are observed for the icos structures (up to 6% compared with bulk interatomic spacings), while small core compressions ({approx} 1 %) are found for the fcc geometry. In contrast, large surface compressive relaxations are found for the fcc clusters ({approx} 2-3% in average nearest neighbor spacing), ...

1996-08-01

417

Effect of pitting corrosion on local strength of hold frames of bulk carriers (1st report)  

Energy Technology Data Exchange (ETDEWEB)

Firstly, pitting corrosion observed on hold frames in cargo holds of bulk carriers which exclusively carry coal and iron ore has been investigated in detail. It was shown that the shape of the corrosion pits observed on them is a circular cone and the ratio of the diameter to the depth is in the range between 8 to 1 and 10 to 1, which is different from the trend observed for the bottom shell of the oil tanker where the ratio is in the range between 4 to 1 and 6 to 1. Secondly, a series of tensile tests has been conducted to investigate the effect of pitting corrosion on tensile strength of members. It was pointed out that the tensile strength decreases gradually and the total elongation decreases drastically with the increase of the thickness loss due to pitting corrosion. The reduction of the tensile strength of the members with pitting corrosion is larger than that of members with uniform thickness loss in terms of average thickness loss. Thirdly, a series of ...

2004-09-01

418

Design variables for mechanical properties of bone tissue scaffolds.  

Science.gov (United States)

The reconstruction of segmental defect in long bone is a clinical challenge. Multiple surgeries are typically required to restore the structure and function of the affected defect site. In order to overcome this defect a biodegradable bone tissue engineering scaffold is used. This scaffold acts as a carrier of proteins and growth factors, while also supporting the load that the bone would normally sustain, until the natural bone can regenerate in its place. Work was done to optimize an existing solid free-form scaffold design. The goal of the optimization was to increase the porosity of the scaffold while maintaining the strength of a previously-tested prototype design. With this in mind, eight new designs were created. These designs were drawn using CAD software and then through the use of finite element analysis the theoretical ultimate compressive strength of each design was obtained. Each scaffold design was constructed by casting a thermal-curable ...

2006-01-01

419

Damping properties of sequoia and birch under shock loading  

International Nuclear Information System (INIS)

The decrease mechanic effect on loads being transported, shock load limiters (dampers) are being widely used today. Usually, the materials having 'stress-strain' diagrams (#sigma#-#epsilon#) of compression with a substantial portion, where #sigma# = const., are used as dampers. Most widely used are dampers made of foam polystyrene having just the same compression diagram. Similar strain diagrams can be enlisted for some porous materials, timber under cross compression, perforated metallic crushers and some others. By selecting damper material, the level of transmitted to the protected object pressures can be varied from several to hundreds MPa. Timber, as being widely used and featuring good technologic properties together with low cost, becomes an attractive material to be used as the limiter of shock loads. This paper presents the results of stress-strain sequoia properties (USA deliverable) and birch properties ...

1998-05-10

420

Behavior of fiber reinforcements and resin flow during the injection-pultrusion process  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the work described in this dissertation is to increase the understanding of injection-pultrusion process. Three major substudies related to injection-pultrusion have been completed: measurement of the compressibility of fiber reinforcements, measurement of in-plane and transverse resin flow through fiber reinforcements, and development of a resin flow model. This dissertation also presents results of an experimental and analytical investigation of in-plane and transverse resin flow through fiber reinforcements.

1990-01-01

421

AUTOMATIC LIQUID NITROGEN PUMPING SYSTEM FOR PARTICLE ACCELERATORS  

Science.gov (United States)

A description is given of an automatic liquid nitrogen pumping system. Pamping of liquid nitrogen iato cooling traps up to a predetermined level is achieved by an automatically controlled compressed air system. An impontant feature of the equipment is the ability to switch automatically from an empty liquid nitrogen reservoir to a full one. This allows for a much more flexible operation than in conventional systems where the reservoir has to be replaced manually when empty. (auth)

1963-04-16

422

A multi-megawatt X-band solid state microwave switch  

Energy Technology Data Exchange (ETDEWEB)

The authors present design methodology and initial experimental results for a high power microwave switch. The switch is designed for application to the pulse compression system associated with the Next Linear Collider Test Accelerator (NLCTA). The switch is based on the excitation of a plasma layer within a silicon wafer by either a laser or an electron beam. They investigate problems associated with high power operation of such a switch. They explore solutions to the problems of thermal runaway, avalanche breakdown, photo-emission, and secondary emission.

1995-12-31

423

A comparison of cycle-resolved and ensemble-averaged velocity variations in a diesel engine  

Energy Technology Data Exchange (ETDEWEB)

Laser-Doppler anemometry was used to investigate mean flow and turbulence fields in a direct injection diesel engine, motored at speeds of 1500, 2250 and 3000 rev/min. Both cycle-resolved and ensemble-averaged measurements were made in the upper part of the cylinder during the inlet and compression strokes. The cycle-resolved measurements in the inlet stroke are discussed in this paper.

1989-01-01

424

A High-Wavenumber Viscosity for High-Resolution Numerical Methods  

Energy Technology Data Exchange (ETDEWEB)

Numerical simulations of compressible flows are commonly based on the Euler equations when effects of viscosity are thought to be negligible. These equations admit singular solutions, even in cases where the initial and boundary conditions are smooth. So-called ''Euler solvers'' rely on numerical dissipation, explicitly or implicitly present in the scheme, to regularize the problem, such that physical solutions are selected.

2003-02-19

425

Yellow-emitting AlGaInP double heterostructure laser diode at 77 K grown by atmospheric metalorganic chemical vapor deposition  

Energy Technology Data Exchange (ETDEWEB)

Yellow-emitting pulsed laser operation of an Al/sub 0.37/Ga/sub 0.15/In/sub 0.48/P/Al/sub 0.16/Ga/sub 0.36/In/sub 0.48/P/ Al/sub 0.37/Ga/sub 0.15/In/sub 0.48/P double heterostructure laser diode was obtained at 77 K. The emission wavelength was 579 nm. The threshold current density was 5.6 kA/cm/sup 2/ for a diode with a Si/sub 3/N/sub 4/ insulated 8-..mu..m-wide and 250-..mu..m-long stripe geometry. The device was made from a DH wafer grown by conventional metalorganic chemical vapor deposition using triethyl metals and phosphine as source materials.

1984-11-01

426

Water uptake and exchange kinetics of polyelectrolyte films: a neutron reflectometry study  

Energy Technology Data Exchange (ETDEWEB)

The sequential layer-by-layer adsorption of polyanions and polycations to build polyelectrolyte multilayers has triggered enormous interest in their potential uses in a wide range of fields, from photonic to pharmaceutical applications. We show that the conformation of the solvent swollen films - prior to drying - is determined by the initial adsorption conditions, but can be altered ex-situ by exposure to a liquid phase of very high ionic strength. Recently it has been observed that the swelling depends on the charge of the outermost layer. In the PAH/PSS system we saw that assemblies with PSS as the outermost layer swell more than those with PAH outside. A neutron reflectivity study of this effect in addition indicated the existence of two kinds of water, bound with different strength within the films. Beside an unexpected two-step kinetics of swelling, the reflectivity curves of the layers against vacuum before and after re-hydration in D{sub 2}O vapor did not ...

2007-07-01

427

Void fraction estimation within rod bundles based on three-fluid model and comparison with X-ray CT void data  

Energy Technology Data Exchange (ETDEWEB)

An interfacial shear stress equation in the dispersed-annular two-phase flow regime has been developed, which is based on a three-fluid model consisting of a liquid film on a rod, vapor and entrained liquid associated with a vapor flow. It is an extension of J.G.M. Andersen's procedure that provides a two-fluid interfacial shear stress equation using the drift flux parameters C{sub 0} and V{sub gj}. This interfacial shear stress equation can take into account a phase and velocity distribution through an equivalence between the drift flux parameters and the interfacial shear stress. Using the three-fluid subchannel analysis code TEMPO with the three-fluid interfacial shear stress model the capability of a three-fluid calculation using the drift flux parameters C{sub 0} and V{sub gj} that reproduce a measured void fraction is demonstrated. A comparison was made with advanced X-ray computed tomography (CT) void fraction data within a 4x4 ...

1990-06-01

428

Transmission electron microscope characterization of AlGaInP grown by organometallic vapor phase epitaxy  

Energy Technology Data Exchange (ETDEWEB)

AlGaInP epitaxial layers grown at 690 {degree}C by atmospheric pressure organometallic vapor phase epitaxy are investigated by transmission electron microscopy. For the first time, compositionally modulated and ordered structures are simultaneously observed in AlGaInP alloys. The ordering is of the CuPt type with ordering along the {l brace}111{r brace} directions. The ordered regions appear as plate-like microdomains, while the composition modulation takes the form of a fine columnar constrast oriented along the growth direction. In addition, from the results of (001) plan-view diffraction contrast examination, the principal strain direction associated with the modulation structures is found to be perpendicular to the growth direction and lies in the surface plane. Thus, it is concluded that the spinodal decomposition is initiated and developed on the surface during the growth of the AlGaInP epitaxial layers and, finally, forms the columnar structure.

1990-04-09

429

Transmission electron microscope characterization of AlGaInP grown by organometallic vapor phase epitaxy  

International Nuclear Information System (INIS)

AlGaInP epitaxial layers grown at 690 degree C by atmospheric pressure organometallic vapor phase epitaxy are investigated by transmission electron microscopy. For the first time, compositionally modulated and ordered structures are simultaneously observed in AlGaInP alloys. The ordering is of the CuPt type with ordering along the #left brace#111#right brace# directions. The ordered regions appear as plate-like microdomains, while the composition modulation takes the form of a fine columnar constrast oriented along the growth direction. In addition, from the results of (001) plan-view diffraction contrast examination, the principal strain direction associated with the modulation structures is found to be perpendicular to the growth direction and lies in the surface plane. Thus, it is concluded that the spinodal decomposition is initiated and developed on the surface during the growth of the AlGaInP epitaxial layers and, finally, forms the columnar structure.

430

Thin TiO2 grown by metal?organic chemical vapor deposition on (NH4)2S x -treated InP  

British Library Electronic Table of Contents (United Kingdom)

The electrical characteristics of thin TiO2 films prepared by metal?organic chemical vapor deposition grown on a p-type InP substrate were studied. For a TiO2 film of 4.7?nm on InP without and with ammonium sulfide treatment, the leakage currents are 8.8?10?2 and 1.1?10?4?A/cm2 at +2 V bias and 1.6?10?1 and 8.3?10?4?A/cm2 at ?2?V bias. The lower leakage currents of TiO2 with ammonium sulfide treatment arise from the improvement of interface quality. The dielectric constant and effective oxide charge number density are 33 and 2.5?1013?cm2, respectively. The lowest mid-gap interface state density is around 7.6?1011?cm?2?eV?1. The equivalent oxide thickness is 0.52?nm. The breakdown electric field increases with decreasing thickness in the range of 2.5 to 7.6?nm and reaches 9.3?MV/cm at 2.5?n...

2011-01-01

431

Solidification of radioactive waste effluents  

Energy Technology Data Exchange (ETDEWEB)

A process and apparatus for solidifying radioactive waste liquid containing dissolved and/or suspended solids is disclosed. The process includes chemically treating for pH adjustement and precipitation of solids, concentrating solids with a thin-film evaporator to provide liquid concentrate containing about 50% solids, and drying the concentrate with heated mixing apparatus. The heated mixing apparatus includes a heated wall and working means for shearing dried concentrate from internal surfaces and subdividing dry concentrate into dry, powdery particles. The working means includes a rotor and helical means for positively advancing the concentrate and resulting dry particles from inlet to outlet of the mixing apparatus. The dry particles may also be encapsulated in a matrix material. Entrained particles in the vapor stream from the evaporator and mixer are removed in an integral particle separator and the vapor is subsequently condensed and may ...

1983-10-11

432

Separation of the components of the binary mixture ethanol-water by steam flux in solid phase column; Separacao dos componentes da mistura binaria etanol-agua por passagem do vapor em coluna de fase solida  

Energy Technology Data Exchange (ETDEWEB)

This paper deals with the energy required to separate ethanol from an aqueous solution in a distillation column containing a solid phase. The solid phases evaluated consisted of either an amylatious (ground corn) or a cellulose (sugar cane bagasse) absorber whit particle sizes smaller than 4 mm. The water-retention capacity of each solid phase was measured by passing vapors or ethanol-water mixtures through the solid phase. When starting with initial concentrations bellow the azeotropic point, ethanol concentrations up to 99,5% (on corn) and 97,2% (on sugar cane) were achieved. The water content was evaluated potentiometrically (Karl`Fischer). Regarding the 2-4 mm ground corn solid phase column, the energy consumed was estimated to be reduced by 15,6% and 60% (by weight) ethanol-water mixture respectively. (author) 11 refs., 2 figs., 2 tabs

1987-12-31

433

Room-temperature cw operation of InGaP/InGaAlP visible light laser diodes on GaAs substrates grown by metalorganic chemical vapor deposition  

Energy Technology Data Exchange (ETDEWEB)

Room-temperature cw operation for InGaP/InGaAlP double heterostructure (DH) laser diodes on GaAs substrates was achieved for the first time. The DH wafers were grown by low-pressure metalorganic chemical vapor deposition using methyl metalorganics. A lasing wavelength of 679 nm and a threshold current of 109 mA at 24C were obtained for an inner stripe structure laser diode with a 250- m-long and 7- m stripe geometry. The laser operated at up to 51C. The characteristic temperature T0 was 87 K at around room temperature. The lowest threshold current density, 5.0 kA/cmS, was obtained with a 20- m stripe width laser diode under room-temperature pulsed operation.

1986-01-20

434

Room-temperature continuous-wave operation of an AlGaInP double heterostructure laser grown by atmospheric pressure metalorganic chemical vapor deposition  

Energy Technology Data Exchange (ETDEWEB)

Continuous-wave (cw) operation at temperatures up to 23 /sup 0/C of an Al/sub 0.26/Ga/sub 0.26/In/sub 0.48/P/Ga/sub 0.52/In/sub 0.48/P/ Al/sub 0.26/Ga/sub 0.26/In/sub 0.48/P double heterostructure (DH) laser has been achieved for the first time. The threshold current was 160 mA at 20 /sup 0/C for a device with a 10-..mu..m-wide and 250-..mu..m-long ion-implanted stripe geometry. The emission wavelength was 671 nm during cw operation at 10 /sup 0/C. To reduce thermal resistance to a heat sink, a dually stacked structure made of a thin (approx.0.3 ..mu..m) p-AlGaInP layer and a p-Al/sub 0.76/Ga/sub 0.24/As layer was used as a cladding layer. The DH wafer was grown by atmospheric pressure metalorganic chemical vapor deposition.

1985-11-15

435

Recent Progress in the Growth of Mid-Infrared Emitters by Metal-Organic Chemical Vapor Deposition  

Science.gov (United States)

We report on recent progress and improvements in the metal-organic chemical vapor deposition (MOCVD) growth of mid-infrared lasers and using a high speed rotating disk reactor (RDR). The devices contain AlAsSb active regions. These lasers have multi-stage, type I InAsSb/InAsP quantum well active regions. A semi-metal GaAsSb/InAs layer acts as an internal electron source for the multi-stage injection lasers and AlAsSb is an electron confinement layer. These structures are the first MOCVD multi-stage devices. Growth in an RDR was necessary to avoid the previously observed Al memory effects found in conventional horizontal reactors. A single stage, optically pumped laser yielded improved power (greater than 650 mW/facet) at 80K and 3.8um. A multi-stage 3.8-3.9um laser structure operated up to T=170K. At 80K, peak power greater than 100mW and a high slope- efficiency were observed in gain guided lasers.

1998-01-01

436

Photoluminescence linewidths in metalorganic vapor phase epitaxially grown ordered and disordered InAlGaP alloys  

International Nuclear Information System (INIS)

The dependence of the photoluminescent properties of In_0_._4_8(Al_yGa_1_-_y)_0_._5_2P alloys (0#<=#y#<=#0.5) on growth temperature and substrate misorientation off GaAs(100) has been studied. Samples were grown using low-pressure metalorganic vapor phase epitaxy. By studying the dependence of ordering behavior in InGaP as a function of substrate misorientation and growth temperature simultaneously, a very large range in low-temperature photoluminescence emission energy---135 meV---has been obtained. The photoluminescence linewidth exhibits a strong, continuous dependence on the extent of atomic ordering (the emission energy) in the alloys. The results indicate that inhomogeneity in the microstructure of the material (i.e., between ''ordered'' domains and the ''disordered'' matrix) is the dominant photoluminescence broadening mechanism. This investigation has allowed a significant optimization of the optical properties of these materials, including the ...

437

Optimization of water injection into vapor-dominated geothermal reservoirs  

Energy Technology Data Exchange (ETDEWEB)

Water injection into a vapor-dominated geothermal reservoir is an effective method of sustaining steam production from the field. Injection puts additional water to the reservoir and raises the prevailing reservoir pressure. This process improves the field`s productivity. However, the increased pressure also increases the water retention capacity of the reservoir rocks through the effects of adsorption and capillary condensation. Due to the significant costs associated with water injection programs, optimizing injection not only involves maximizing the energy yield from the resource but also the present worth of the project. Two crucial parameters that need to be established are: (1) how much to inject; and, (2) when to inject it. This study investigated the optimal design of these parameters. It was found that comparable energy yield can be attained for injection programs that are initiated at various stages of the field`s development. Higher injection rates are ...

1996-12-31

438

OXYGEN-ENRICHED COAL COMBUSTION WITH CARBON DIOXIDE RECYCLE AND RECOVERY: SIMULATION AND EXPERIMENTAL STUDY  

Energy Technology Data Exchange (ETDEWEB)

Two computational problems were worked on for this study. The first chapter examines the option of coal combustion using oxygen feed with carbon dioxide recycle to control the adiabatic flame temperature. Computer simulations using an existing state-of-the-art 3-dimensional computer code for turbulent reacting flows with reacting particles were employed to study the effects of increased carbon dioxide mole fraction on the char burnout, radiant heat transfer, metal partitioning, and NOx formation. The second chapter compares assumptions for the CO/CO{sub 2} ratio at the surface of mineral inclusions made in previous studies to predictions obtained from a pseudo-steady state kinetic model (SKIPPY) for a single porous particle. The detailed kinetic simulations from SKIPPY for varying particle sizes and bulk gas compositions were used to develop algebraic expressions for the CO/CO{sub 2} ratio that can be incorporated into metal vaporization sub-models run as a post ...

2002-02-28

439

Modeling of thermal and hydrodynamic aspects of molten jet/water interactions  

Energy Technology Data Exchange (ETDEWEB)

In order to predict the effect of a fuel-coolant interaction after a hypothetical core-melt-down accident, a phenomenological model has been developed to describe the thermal and hydrodynamic behavior of a high-temperature molten jet when it interacts with saturated or subcooled water in a film boiling regime. The mechanisms of jet-material erosion were analyzed by Kelvin-Helmholtz instabilities on the coherent column and by boundary layer stripping on the leading edge. The heat transfer coefficient, vapor-film thickness, and net steam generation, all of which strongly affect the jet-breakup behavior, were solved analytically. It was found that the jet breakup (or erosion) depends strongly on the steam generation from the jet/water interaction. The jet-breakup length (i.e., penetration distance) was found to be sensitive to the initial jet temperature, water subcooling, and the physical state of the ambient water. The jet-breakup length and leading-edge velocity of ...

1989-01-01

440

Magnetic field amplification and generation in hypervelocity meteoroid impacts with application to lunar paleomagnetism  

International Nuclear Information System (INIS)

A one-dimensional numerical model for the expansion of impact-produced vapor clouds is used to investigate magnetic field generation mechanisms in events such as meteor collisions with the moon. The resulting cloud properties, such as ionization fraction, electrical conductivity, radial expansion velocity, mass density, and energy density are estimated. The model is initiated with the peak shock states and pressure thresholds for incipient and complete vaporization of anorthosite lunar surface materials by iron and GA composition meteorites. The expansion of the spherical gas cloud into a vacuum was traced with a one-dimensional explicit lagrangian hydrodynamic code. The hypervelocity impact plasmas produced are found to be significant in the amplitudes and orientations of the magnetic fields generated. An ambient magnetic field could have been provided by the core dynamo, which would have interacted with the expanding plasmas and formed ...

1984-03-12

441

Isotope exchange reaction between tritiated water and hydrogen on SiC  

Energy Technology Data Exchange (ETDEWEB)

SiC has been considered as a primary candidate material for a first wall component in future fusion reactor because it has been claimed that SiC has excellent high-temperature properties, good chemical stability and low activation. However, the behavior of tritium on SiC has not been discussed yet. In this study, tritium trapping capacity on the surface of SiC was experimentally obtained at the temperature range of 25-800 deg. C in consideration of tritium trapping to the experimental system. The capacity, which was independent of the water vapor pressure in the gas phase and the temperature, was determined as about 10{sup 6} Bq/cm{sup 2}. The isotope exchange reaction rate between tritiated water in a gas phase and hydrogen on the surface was quantified at the temperature of 25, 500 and 700 deg. C in consideration of the behavior of tritium trapping at change of experimental condition by the numerical curve fitting method applying the serial reactor model. The ...

2003-11-15

442

Isotope exchange reaction between tritiated water and hydrogen on SiC  

International Nuclear Information System (INIS)

SiC has been considered as a primary candidate material for a first wall component in future fusion reactor because it has been claimed that SiC has excellent high-temperature properties, good chemical stability and low activation. However, the behavior of tritium on SiC has not been discussed yet. In this study, tritium trapping capacity on the surface of SiC was experimentally obtained at the temperature range of 25-800 deg. C in consideration of tritium trapping to the experimental system. The capacity, which was independent of the water vapor pressure in the gas phase and the temperature, was determined as about 10"6 Bq/cm"2. The isotope exchange reaction rate between tritiated water in a gas phase and hydrogen on the surface was quantified at the temperature of 25, 500 and 700 deg. C in consideration of the behavior of tritium trapping at change of experimental condition by the numerical curve fitting method applying the serial reactor model. The reaction rate ...

2003-11-15

443

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

444

Horizontal liquid film mist two-phase flow, 2. Droplet deposition and entrainment rates  

Energy Technology Data Exchange (ETDEWEB)

In the region of annular liquid film-mist flow, the behavior of the droplets formed from the liquid film and the rate of formation are the subjects to be clarified in connection with the forecast of dry-out point, which becomes a problem in the region of high dryness such as reactor cooling system and steam generators. Many researches have been performed on such problem in vertical tubes, but the characteristics in horizontal flow have not yet been sufficiently clarified. This series of research is to clarify various characteristics, such as the velocity of vapor phase, the flow rate distribution of droplets, the formation and adhesion of droplets and the structure of liquid film, in the region of liquid film-mist flow, where liquid film exists on the bottom of a horizontal rectangular channel, and vapor flow is accompanied by droplets. In this study, by the measurement of the flow rate distribution of droplets on respective cross sections ...

1984-06-01

445

Horizontal liquid film mist two-phase flow, 2  

International Nuclear Information System (INIS)

In the region of annular liquid film-mist flow, the behavior of the droplets formed from the liquid film and the rate of formation are the subjects to be clarified in connection with the forecast of dry-out point, which becomes a problem in the region of high dryness such as reactor cooling system and steam generators. Many researches have been performed on such problem in vertical tubes, but the characteristics in horizontal flow have not yet been sufficiently clarified. This series of research is to clarify various characteristics, such as the velocity of vapor phase, the flow rate distribution of droplets, the formation and adhesion of droplets and the structure of liquid film, in the region of liquid film-mist flow, where liquid film exists on the bottom of a horizontal rectangular channel, and vapor flow is accompanied by droplets. In this study, by the measurement of the flow rate distribution of droplets on respective cross sections ...

1984-01-01

446

Flux pinning and critical currents in A-15 superconductors  

Science.gov (United States)

The relationship between processing, microstructure, and properties was studied for A-15 compounds in multifilamentary composites produced by solid-state diffusion and in thin-film samples produced by vapor deposition. Grain sizes of A-15 superconducting compounds were measured by transmission electron microscopy of multifilamentary composites reacted at various temperatures. Critical current densities at 4.2 K and fields up to 6 T were found to be similar for niobium-tin, vanadium-gallium, and vanadium-silicon of the same grain size. Study of the Cu-V-Si phase diagram led to the production of improved multifilamentary vanadium-silicon conductors. The effects of various alloying elements on A-15 layers produced by solid-state diffusion were studied. The most promising new observation was that tantalum can be incorporated into niobium-tin reaction layers, leading to an enhancement of critical currents at high fields. The critical temperature of ...

1978-02-01

447

Evaluation of the cleanliness of ultrapure water by the analysis for metal concentration deposited on Si wafer surface using vapor phase decomposition/inductively coupled plasma mass spectrometry  

International Nuclear Information System (INIS)

Along with the shrinkage of LSI geometries, a higher quality of ultrapure water has been continuously required. Analytical technology for ultrapure water has also progressed before ultrapure water production technology improvements. In this study, we performed optimization of the analytical conditions for the direct analysis of acid droplets, and established an analytical technology for measurements of trace amounts of metallic impurities deposited on a wafer surface by means of Vapor Phase Decomposition (VPD)/Inductively Coupled Plasma Mass Spectrometry (ICP-MS). As a result, analytical technology for metallic elements of the 1x10"8 atoms/cm"2 level on wafer surface has been established. By applying analytical technology to the wafer that has been contacted with ultrapure water, a new evaluation technology for ultrapure water quality by means of wafer surface contamination has been established. We confirmed good correlations between metal contamination of the ...

2010-07-01

448

Estimation of vapour pressure over MOX fuel  

International Nuclear Information System (INIS)

Use of high plutonia MOX as fuel is contemplated from the point of view of rapid disposition of plutonium and economic power generation. The fuel pellets are subjected to steep thermal gradients #approx# 1700 K drop across a radius of #approx# 2.5mm. This leads to evaporation-condensation of the fuel constituents to cooler regions. Vaporization depends on fuel compositions such as Pu fraction, Oxygen-to-Metal (O/M) ratio and local temperature. Knowledge of vapour chemistry is essential in understanding the fuel behavior. The vaporization behaviour of MOX was analyzed in this work using thermochemical methods. The vapour phase consisted of nine species; O, O_2, Pu, PuO, PuO_2, U, UO, UO_2 and UO_3. Oxygen formed part of the vapour phase along with other species and oxygen potential was not controlled independently. The vapour pressures were estimated at 2000 K as a function of (O/M) for several Pu-fraction. Results for MOX-28%PuO_2 is shown in ...

2010-12-01

449

Electrical properties of ultra-thin oxynitrided layer using N{sub 2}O plasma in inductively coupled plasma chemical vapor deposition for non-volatile memory on glass  

Energy Technology Data Exchange (ETDEWEB)

In this work, the silicon oxynitride layer was studied as a tunneling layer for non-volatile memory application by fabricating low temperature polysilicon thin film transistors on glass. Silicon wafers were oxynitrided by only nitrous oxide plasma under different radio frequency powers and plasma treatment times. Plasma oxynitridation was performed in RF plasma using inductively coupled plasma chemical vapor deposition. The X-ray energy dispersive spectroscopy was employed to analyze the atomic concentration ratio of nitrogen/oxygen in oxynitride layer. The oxynitrided layer formed under radio frequency power of 150 W and substrate temperature of 623 K was found to contain the atomic concentration ratio of nitrogen/oxygen as high as 1.57. The advantage of high nitrogen concentration in silicon oxide layer formed by using nitrous oxide plasma was investigated by capacitance-voltage measurement. The analysis of capacitance-voltage characteristics demonstrated that ...

2007-06-04

450

Electrical properties of ultra-thin oxynitrided layer using N_2O plasma in inductively coupled plasma chemical vapor deposition for non-volatile memory on glass  

International Nuclear Information System (INIS)

In this work, the silicon oxynitride layer was studied as a tunneling layer for non-volatile memory application by fabricating low temperature polysilicon thin film transistors on glass. Silicon wafers were oxynitrided by only nitrous oxide plasma under different radio frequency powers and plasma treatment times. Plasma oxynitridation was performed in RF plasma using inductively coupled plasma chemical vapor deposition. The X-ray energy dispersive spectroscopy was employed to analyze the atomic concentration ratio of nitrogen/oxygen in oxynitride layer. The oxynitrided layer formed under radio frequency power of 150 W and substrate temperature of 623 K was found to contain the atomic concentration ratio of nitrogen/oxygen as high as 1.57. The advantage of high nitrogen concentration in silicon oxide layer formed by using nitrous oxide plasma was investigated by capacitance-voltage measurement. The analysis of capacitance-voltage characteristics demonstrated that ...

2007-06-04

451

Corrosion behavior of materials at high temperature by environmental oxidants containing sulfur derivatives: effects of aggressive phase composition on experimental alloys. Final report  

Energy Technology Data Exchange (ETDEWEB)

For a better understanding of sulphidation mechanisms, some alloys (alloy 600, alloy 800, Uranus S, iron-chromium-aluminium-alloy) and metals (iron, chromium, nickel, molybdenum, titanium) were tested at 773, 873, 1 073 K in gaseous sulphur dioxide. Total pressure was 760 torrs. Sulphur dioxide pressure was 760, 100 and 10 torrs. Argon, oxygen, water vapor were used, successively, as pressure complement. Oxygen supply, generally speaking cause decay of corrosion resistance in SO/sub 2/ atmospheres especially at 1 073 K with low ratio p/sub O2//P/sub SO/sub 2//. Water vapor supply act similarly. Temperature laws and pressure laws do not give monotonous rise of corrosion values. There are maximas suggesting corrosion products undertaking a volatilization process. According to test conditions, Uranus S, chromium, alloy 800 (and titanium at some extent) showed good corrosion resistance. That results are supporting those obtained by JRC Ispra team, ...

1981-01-01

452

Conversion of a plasma enhanced chemical vapor deposited silicon-carbon-nitride thin film at ultra-low temperature by oxygen plasma  

Energy Technology Data Exchange (ETDEWEB)

In this work we present an ultra-low temperature method for the oxidation of an amorphous silicon-carbide-nitride (SiCN) material. The SiCN is deposited on silicon substrates by plasma enhanced chemical vapor deposition using CH{sub 4}, SiH{sub 4}, and N{sub 2} chemistry. The physical and chemical properties are characterized for the as-deposited SiCN and post-oxidized films are discussed. The SiCN film is exposed to oxygen plasma, where it undergoes a chemical transformation into a binary SiO{sub 2} material system. A 1.7 nm/min oxidation rate is typical for this process and compares favorably to oxidation methods utilizing much higher temperatures. The substrate temperature remains extremely low throughout the oxidation process, T{sub s} < 200 deg. C. Changes in film stress, optical constants, film thickness, surface roughness, and film density are measured. Chemical analysis by X-ray photoelectron spectroscopy is reported for both the as-deposited and ...

2008-01-30

453

Collection of VLE data for acid gas-alkanolamine systems using Fourier transform infrared spectroscopy. Technical report, October 1, 1994--July 31, 1995  

Energy Technology Data Exchange (ETDEWEB)

The industrial standard process for the purification of natural gas is to remove acid gases, mainly hydrogen sulfide and carbon dioxide, by the absorption and reaction of these gases with alkanolamines. The natural gas industry requires vapor-liquid equilibrium (VLE) data to develop more energy efficient amine mixtures. Some energy reductions have been realized in the past decade by applying such amine systems as hindered amines, methyldiethanolamine (MDEA), and MDEA based amine mixtures. However, the lack of reliable and accurate VLE data impedes the commercial application of these more efficient alkanolamine systems. The first objective of this project is to improve the accuracy of vapor-liquid equilibrium measurements at low hydrogen sulfide concentrations. The second objective is to make VLE measurements for amine mixtures. By improving the accuracy of the VLE data on MDEA and other amines, energy savings can be implemented in the many ...

1995-08-01

454

Collection of VLE data for acid gas-alkanolamine systems using Fourier transform infrared spectroscopy. Phase 1, September 29, 1990--September 30, 1991  

Energy Technology Data Exchange (ETDEWEB)

The industrial standard process for the purification of natural gas is to remove acid gases, mainly hydrogen sulfide and carbon dioxide, by the absorption and reaction of these gases with alkanolamines. Inadequate data for vapor -- liquid equilibrium (VLE) hinder the industry from converting operations to more energy efficient amine mixtures and conserving energy. Some energy reductions have been realized in the past decade by applying such amine systems as ``hindered`` amines, methyldiethanolamine (MDEA), and MDEA based amine mixtures. However, the lack of reliable and accurate fundamental VLE data impedes the commercial application of these more efficient alkanolamine systems. The first project objective is to improve the accuracy of vapor -- liquid equilibrium measurements at low hydrogen sulfide concentrations. The second project objective is to measure the VLE for amine mixtures. By improving the accuracy of the VLE measurements on MDEA ...

1991-09-01

455

Collection of VLE data for acid gas-alkanolamine systems using Fourier transform infrared spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

The industrial standard process for the purification of natural gas is to remove acid gases, mainly hydrogen sulfide and carbon dioxide, by the absorption and reaction of these gases with alkanolamines. Inadequate data for vapor -- liquid equilibrium (VLE) hinder the industry from converting operations to more energy efficient amine mixtures and conserving energy. Some energy reductions have been realized in the past decade by applying such amine systems as hindered'' amines, methyldiethanolamine (MDEA), and MDEA based amine mixtures. However, the lack of reliable and accurate fundamental VLE data impedes the commercial application of these more efficient alkanolamine systems. The first project objective is to improve the accuracy of vapor -- liquid equilibrium measurements at low hydrogen sulfide concentrations. The second project objective is to measure the VLE for amine mixtures. By improving the accuracy of the VLE ...

1991-09-01

456

Carbon dioxide absorption methanol process  

Energy Technology Data Exchange (ETDEWEB)

A process is described for removing carbon dioxide from a feed stream of natural gas, having at least methane, ethane and heavier hydrocarbon, comprising: separating the feed stream in a first separator to form a first stream, having substantially all of the propane and heavier hydrocarbons and carbon dioxide and ethane, and a second stream, having methane, carbon dioxide and ethane; mixing the second stream with a polar compound to form a third stream; separating the vapor and liquid of the third stream in the bottom portion of an absorber; absorbing carbon dioxide and ethane from the separated vapor of Step C in a lean portion of the polar compound in the absorber, the absorber carbon dioxide and ethane forming a fourth stream; separating the ethane from the polar compound and carbon dioxide in a separator; separating the first stream in a third separator to separate the propane and heavier hydrocarbons from the carbon dioxide and ethane: ...

1987-06-23

457

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. In Campaign 3 of the pilot plant, the overall mass transfer coefficient for the stripper with 7 m MEA decreased from 0.06 to 0.01 mol/(m{sup 3}.s.kPa) as the rich loading increased from 0.45 to 0.6 mol CO{sub 2}/mol MEA. Anion chromatography has demonstrated that nitrate and nitrite are major degradation products of MEA and PZ with pure oxygen. In measurements with the high temperature FTIR in 7 m MEA the MEA vapor pressure varied from 2 to 20 Pa at 35 to 70 C. In 2.5 m PZ the PZ vapor pressure varied from 0.2 to 1 Pa from 37 to 70 C.

2005-01-26

458

Advanced evaporator technology progress report FY 1992  

Energy Technology Data Exchange (ETDEWEB)

This report summarizes the work that was completed in FY 1992 on the program {open_quotes}Technology Development for Concentrating Process Streams.{close_quotes} The purpose of this program is to evaluate and develop evaporator technology for concentrating radioactive waste and product streams such as those generated by the TRUEX process. Concentrating these streams and minimizing the volume of waste generated can significantly reduce disposal costs; however, equipment to concentrate the streams and recycle the decontaminated condensates must be installed. LICON, Inc., is developing an evaporator that shows a great deal of potential for this application. In this report, concepts that need to be incorporated into the design of an evaporator operated in a radioactive environment are discussed. These concepts include criticality safety, remote operation and maintenance, and materials of construction. Both solubility and vapor-liquid equilibrium data are needed to ...

1995-01-01

459

626. 2-nm pulsed operation (300 K) of an AlGaInP double heterostructure laser grown by metalorganic chemical vapor deposition  

Energy Technology Data Exchange (ETDEWEB)

Room-temperature pulsed laser operation of (Al/sub 0.55/Ga/sub 0.45/)/sub 0.5/In/sub 0.5/P /(Al/sub 0.17/Ga/sub 0.83/)/sub 0.5/In/sub 0.5/P / (Al/sub 0.55/Ga/sub 0.45/)/sub 0.5/In/sub 0.5/P double heterostructure laser diodes grown by metalorganic chemical vapor deposition has been achieved. The lasing wavelength is 626.2 nm, which is the shortest ever reported for an AlGaInP double heterostructure laser. Threshold current density is 50 kA/cm/sup 2/ for a diode with a 20-..mu..m-wide and 200-..mu..m-long stripe.

1985-01-01

460

Visible semiconductor lasers with the AlGaInP materials system  

International Nuclear Information System (INIS)

The AlGaInP materials system has recently supported the development of a variety of visible diode laser devices at wavelengths ranging from yellow to red. Presently, the majority of published results are with materials prepared by organometallic vapor phase epitaxy (OMVPE). Many issues with such materials exist, including impurity doping, the role of crystal ordering, defect formation during epitaxial growth, and the proper quantum well heterostructure design required for best device results. This paper addresses these topics and reviews the present state of the art, and projects the anticipated results when the materials' problems have been solved.

1988-11-02

461

Understanding the operation and use of high temperature electrochemical corrosion rate probes  

Energy Technology Data Exchange (ETDEWEB)

Electrochemical corrosion rate probes were constructed and tested along with mass loss coupons in a N2/O2/CO2 plus water vapor environment. Temperatures ranged from 450 to 600 C. Corrosion rates for ash-covered mild steel, 304L SS, and 316L SS probes using electrochemical techniques were a function of time, temperature, and process environment. Correlation between electrochemical and mass loss corrosion rates was good.

2004-01-01

462

Tubular packs Mo-AlN-Mo: long-term thermal and corrosion resistance  

International Nuclear Information System (INIS)

Study results on long-term thermal and corrosion resistance of packs with electro-insulation layer of aluminium nitride are presented. Structural changes of nitride ceramics and contact zones between metal and ceramics are considered. It is shown that multilayer metallo-ceramic packs, manufactured by gas-phase technology have high electro- and thermophysical properties, high thermal and corrosion resistance relative to cesium vapor, vacuum density as well as high thermo-resistance. 8 refs., 4 figs.

463

Structure and electrical resistance of dispersion-strengthened vacuum-deposited Cu?Al2O3 nanocomposites  

British Library Electronic Table of Contents (United Kingdom)

Methods of X-ray diffraction and transmission electron microscopy were used to study the microstructure of dispersion-strengthened Cu-Al2O3 nanocomposites obtained by the method of simultaneous deposition of Cu and Al2O3 from the vapor phase. The effect of the size of particles of the oxide (Al2O3) and of their content on the electrical resistance of the composite has been considered. The results obtained make it possible to suppose that the main structural factor that determines the electrical resistance of the composite are nanodispersed particles of Al2O3 with a size of less than 20 nm.

2011-01-01

464

Simple method for high-temperature separation of thallium isotopes from a bulk lead target  

Energy Technology Data Exchange (ETDEWEB)

A method is proposed for the quantitative isolation of radiothallium in gas form from proton-bombarded lead of mass up to 20 g. The molten lead is kept at about 800 K in hydrofluoric-acid vapor (HF/H/sub 2/O approx. = 1) at a reduced pressure (less than or equal to4 Pa). We used 99.9% lead with the U-240 cyclotron at the Nuclear Research Institute, Academy of Sciences of the Ukrainian SSR, or the phasotron at the Join Nuclear Research Institute, which gave protons at 65 and 680 MeV correspondingly.

1988-03-01

465

Simple method for high-temperature separation of thallium isotopes from a bulk lead target  

International Nuclear Information System (INIS)

A method is proposed for the quantitative isolation of radiothallium in gas form from proton-bombarded lead of mass up to 20 g. The molten lead is kept at about 800 K in hydrofluoric-acid vapor (HF/H_2O #approx =# 1) at a reduced pressure (#<=#4 Pa). We used 99.9% lead with the U-240 cyclotron at the Nuclear Research Institute, Academy of Sciences of the Ukrainian SSR, or the phasotron at the Join Nuclear Research Institute, which gave protons at 65 and 680 MeV correspondingly.

466

Review of the application of molecular beam epitaxy for high efficiency solar cell research  

Energy Technology Data Exchange (ETDEWEB)

In the last two years, rapid progress has been made in the energy conversion efficiencies of GaAs solar cells fabricated from molecular beam epitaxy (MBE) material. The efficiencies of cells fabricated from MBE material are now comparable with those fabricated from metal-organic chemical vapor deposition material, even for cells of dimension 2 cmx4 cm. This paper reviews the progress in MBE cell efficiencies. Also discussed is the role oval defects play in GaAs diode and solar cell performance. (orig.).

1991-05-01

467

Reactive sticking coefficients for silane and disilane on polycrystalline silicon  

Energy Technology Data Exchange (ETDEWEB)

Reactive sticking coefficients (RSCs) were measured for silane and disilane on polycrystalline silicon for a wide range of temperature and flux (pressure) conditions. The data were obtained from deposition-rate measurements using molecular beam scattering and a very low-pressure cold-wall reactor. The RSCs have nonlinear Arrhenius temperature dependencies and decrease with increasing flux at low (710 /sup 0/C) temperatures. Several simple models are proposed to explain these observations. The results are compared with previous studies of the SiH/sub 4//Si(s) reaction and low-pressure chemical vapor deposition-rate measurements.

1988-04-15

468

Radio frequency He/sup -/ source and a source of negative ions by cesium sputtering  

Energy Technology Data Exchange (ETDEWEB)

Two sources of negative ions are described. An rf source produces up to 14 ..mu..A beams of He/sup -/ by charge exchange in Rb vapor. The other Source of Negative Ions by Cesium Sputtering (SNICS) produces a wide variety of negative ion beams in the ..mu..A range. Two important features of SNICS are its simple, compact construction and its very good beam emittance (2 to 4..pi..mm mrad MeV/sup 1/2/). Both sources have lifetimes >200 hours and they are used extensively on the Wisconsin EN tandem.

1981-04-01

469

Quality engineering and control. Semiannual progress report, May-October 1979  

International Nuclear Information System (INIS)

The following are reported: colorimetric determination of Ti in Cr, decontamination of metals by anodic dissolution, computer code for x-ray peak identification, gel-permeation chromatography of CoRezyn 1664 polyester resin, infrared monitoring of gases and vapors, particle size analysis of dusts, nondestructive analysis of Oralloy for removable alpha contamination, dissolution (digestion) of high-fired oxides, assay of U in a Pu-U alloy, measurement of oxide thickness on Pu metal by x-ray diffraction, analysis of precipitated Pu peroxide, differentiation of Dowex SBR and 11 resins, and determination of Pu solubility in simulated lung fluid.

470

Problems in modeling of small break LOCA. Technial report  

Energy Technology Data Exchange (ETDEWEB)

The report deals with: (1) two-phase flow regime transitions, (2) liquid entrainment in break flow, (3) vapor pull-through, and (4) CCFL in horizontal ducts. The first three processes influence the mass flow through the break, whereas the fourth one imposes a limit on liquid flow from the steam generator through the hot leg break into the core. Correlations available in the literature which deal with these processes are presented and applied to a hot leg of a PWR, LOFT and Semiscale for quantitative estimates, as well as for determining the scale distortion in the latter two facilities.

1980-10-01

471

Preparation and analysis of Si_3N_4 film  

International Nuclear Information System (INIS)

Microwave Electron Cyclotron Resonance (ECR) Plasma assisted Chemical Vapor Deposition (CVD) technology has been used to prepare Si_3N_4 films, which were analyzed by using infrared (IR) transmission spectroscopy and XPS. The analysis results show that with the increase of the deposition temperature, the H content decrease, and the densification of the film increases. When the temperature is up to 360 degree C, the stoichiometrical rate of Si:N is close to 0.75. The protective property of Si_3N_4 films is also examined

2000-04-01

472

Plasma Enhanced Chemical Vapor Deposition (PECVD) Application And Atmospheric Pressure Plasma Characteristics  

International Nuclear Information System (INIS)

Atmospheric pressure plasma enhanced chemical vapour deposition system is built. The electrical and optical characteristics of the APPECVD system is given. The system is used to deposit conductive polymers and nano composites onto glass and metal surfaces. The morphological, optical, chemical and electrical characteristics of deposited surfaces are investigated using SEM, AFM four probe deposition purposes. The photovoltaic applications of plasma deposited polymers and nonconsumption are compared with deposited with electrochemical methods show different results. The electrical, chemical and morphological structures of the samples will be given.

2008-08-25

473

On the development of a laser detonator  

Science.gov (United States)

The initiation of explosives by laser illumination has been known for many years. In this paper we will discuss the development of a working detonator design that reduces the energy required for detonation in a low-density secondary explosive by vaporizing a thin metal coating. We present data on the development of the design for a workhorse laser detonator that provides enhanced safety over existing exploding bridgewire detonators (EBWs). Comparison of this laser initiated data to an exploding-bridgewire (EBW) provides insight into the mechanism of initiation of detonation in low-density PETN by the plasma source. A novel diagnostic technique to determine the run-distance to detonation also known as the apparent Center-of-Initiation (COI) will also be discussed.

2005-09-01

474

Microcantilever detector for explosives  

Energy Technology Data Exchange (ETDEWEB)

Methods and apparatus for detecting the presence of explosives by analyzing a vapor sample from the suspect vicinity utilize at least one microcantilever. Explosive gas molecules which have been adsorbed onto the microcantilever are subsequently heated to cause combustion. Heat, along with momentum transfer from combustion, causes bending and a transient resonance response of the microcantilever which may be detected by a laser diode which is focused on the microcantilever and a photodetector which detects deflection of the reflected laser beam caused by heat-induced deflection and resonance response of the microcantilever. 2 figs.

1999-06-29

475

Method for production of uranium dioxide particles from uranium hexafluoride by growing process in fluidized bed  

International Nuclear Information System (INIS)

Processes of production and purification (necessary for fabricating fuel elements) of powdery uranium dioxide with particle size up to 1000 #mu#m and more have been studied. Developed is continuous process of UO_2 production with above particle size by converting uranium hexafloride into UO_2 solid particles in fluidized bed while their interaction with water vapor and hydrogen on the uranium dioxide nucleus material. The method allows to conduct continuous selection from the apparatus of UO_2 powder fraction with particle size near 1000 #mu#m without nucleus material additional feed.

476

Innovative technology summary report: in situ air stripping using horizontal wells  

Energy Technology Data Exchange (ETDEWEB)

In situ air stripping (ISAS) technology was developed to remediate soils and ground water contaminated with volatile organic compounds (VOCs) both above and below the water table. ISAS employs horizontal wells to inject (sparge) air into the ground water and vacuum extract VOCs from vadose zone soils. The innovation is creation of a system that combines two somewhat innovative technologies, air sparging and horizontal wells, with a baseline technology, soil vapor extraction, to produce a more efficient in situ remediation system.

1995-04-01

477

In situ bioremediation using horizontal wells  

Energy Technology Data Exchange (ETDEWEB)

In Situ Bioremediation (ISB), which is the term used in this report for Gaseous Nutrient Injection for In Situ Bioremediation, remediates soils and ground water contaminated with volatile organic compounds (VOCs) both above and below the water table. ISB involves injection of air and nutrients (sparging and biostimulation) into the ground water and vacuum extraction to remove .VOCs from the vadose zone concomitant with biodegradation of VOCs. The innovation is in the combination of 3 emerging technologies, air stripping, horizontal wells, and bioremediation via gaseous nutrient injection with a baseline technology, soil vapor extraction, to produce a more efficient in situ remediation system.

1995-04-01

478

Hermetically sealed aluminum electrolytic capacitor  

Science.gov (United States)

Aluminum electrolytic capacitors are presently not allowed on NASA missions because they outgas water and organic vapors, as well as H2. As a consequence, much larger and heavier packages of tantalum capacitors are used. A hermetically sealed aluminum capacitor has been developed under NASA-MSFC SBIR contracts. This capacitor contains a nongassing electrolyte that was developed for this application so internal pressure would remain low. Capacitors rated at 250 to 540 V have been operated under full load for thousands of hours at 85 and 105 C with good electrical performance and low internal pressure. Electrolyte chemistry and seal engineering concepts will be discussed.

1995-04-01

479

Fossil Energy Program. Progress report for April 1978  

Science.gov (United States)

This report--the forty-fifth of a series--is a compendium of monthly progress reports for the ORNL research and development programs that are in support of the increased utilization of coal and other fossil fuel alternatives to oil and gas as sources of clean energy. The projects reported this month include those for coal conversion process development, materials engineering, alkali metal vapor topping cycles, a coal equipment test program, an AFB coal combustor for cogeneration (CCC), engineering and support studies, process and program assistance, evironmental assessment studies, magnetic beneficiation, and AFBC demonstration plant.

1978-06-01

480

Energetical analysis of sensitivity of hydrogen embrittlement of ordered alloys  

Science.gov (United States)

Intermetallic compounds are regarded as highly promising for applications as high temperature structural materials. However, recent studies have demonstrated that a number of ordered alloys exhibit environmental embrittlement when tested in various environments at ambient temperature. When exposed to hydrogen gas or electrolytically charged with hydrogen, a significant ductility loss has been reported. The reaction of water vapor with reactive elements in the crack tip results in the generation of atomic hydrogen which diffuses from the surface to the interior and causes embrittlement. In this paper, the authors try to analyze the sensitivity of hydrogen embrittlement of ordered alloys based upon energetical considerations.

1993-10-01

481

Effect of induced instability by subcooled boiling vibration of heated rod  

International Nuclear Information System (INIS)

In the present study, a subcooled boiling loop with an annular flow on the electrically heated rod was used to make an experimental approach to investigate the effects of induced instability by the subcooled boiling on vibration of the rod in different subcooled conditions. The results show the intensive subcooled-boiling-induced vibration (SBIV) which is highly depend on dynamic force generated by fast vapor bubbles growth and collapse whilst they still attach to, or slide along, the heating surface at high loading heat fluxes. These behaviors were strongly influenced by the conditions of subcooling temperature, flow rate and linear power density. (author)

1998-05-01

482

Effect of Carbon Dioxide in the Air on Zinc-air Cell  

Energy Technology Data Exchange (ETDEWEB)

The electrolyte was brought into contact with air and potassium carbonate was measured with various contact time in order to check the defect of carbon dioxide in the air on zinc-air cell. The relationship between potassium carbonate concentration in electrolyte and battery capacity was also studied. The potassium carbonate concentration in the electrolyte. The rate of carbon dioxide absorption was mainly affected by the pore size of hydrophobic membrane. Our study showed that adapting the pore of hydrophobic membrane decreased the loss of cell discharge performance due to the presence of carbon dioxide or water vapor in the atmosphere. 7 refs., 12 figs., 1 tab.

1999-04-01

483

Core preservation with a laminated, heat-sealed package  

Energy Technology Data Exchange (ETDEWEB)

A core preservation package was developed to maintain the reservoir characteristics of core samples and consequently to improve the quality of data obtained through laboratory core analyses. The package is a heat-sealable plastic-aluminum laminate similar to those common in the food-packaging industry. The laminated core preservation package acts as an impermeable barrier to water vapor and gases, and is resistant to chemical alteration and degradation by core fluids. These performance characteristics result in effective core preservation by maintaining the fluid content of the core. Other advantages of the laminated package are that it is fast and simple to use and eliminates the cumbersome dip-coat step used in some core preservation methods.

1988-12-01

484

Continuous wave operation (77 K) of yellow (583. 6 nm) emitting AlGaInP double heterostructure laser diodes  

Science.gov (United States)

Continuous wave lasing operation with the shortest wavelength for semiconductor lasers was obtained from AlGaInP double heterostructure lasers at 77 K. The structure was grown by metalorganic vapor phase epitaxy. Lasing wavelength was 583.6 nm (yellow). Threshold current was 43 mA (1.9 kA/cm/sup 2/). Magnesium was adopted as a p-type dopant, and was proved to be preferable for a high aluminum composition AlGaInP cladding layer.

1986-03-03

485

Catalysis over activated high silica zeolites  

Science.gov (United States)

A process is provided for conducting organic compound conversion over a catalyst composition comprising a specially treated crystalline zeolite having a high initial silica-to-alumina mole ratio, said zeolite having been synthesized from a reaction mixture comprising a diamine as a cation source. The treatment of the zeolite material comprises the sequential steps of reacting the zeolite with a dilute hydrogen fluoride solution, contacting the hydrogen fluoride solution reacted material with aluminum chloride vapor, and then treating the aluminum chloride contacted material to convert it to hydrogen form.

1985-05-07

486

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

487

A quantitative method to detect explosives and selected semivolatiles in soil samples by Fourier transform infrared spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

This paper describes a novel Fourier transform infrared (FTIR) spectroscopic method that can be used to rapidly screen soil samples from potentially hazardous waste sites. Samples are heated in a thermal desorption unit and the resultant vapors are collected and analyzed in a long-path gas cell mounted in a FTIR. Laboratory analysis of a soil sample by FTIR takes approximately 10 minutes. This method has been developed to identify and quantify microgram concentrations of explosives in soil samples and is directly applicable to the detection of selected volatile organics, semivolatile organics, and pesticides.

1995-06-01

488

Vapor fraction measurements in a steam-water tube at up to 15 bar using neutron radiography techniques  

Energy Technology Data Exchange (ETDEWEB)

Real time neutron radiography has been used to study the dynamic behavior of two phase flow and measure the time averaged vapor fraction in a heated metal tube containing boiling steam water operating at up to 15 bar pressure. The neutron radiographic technique is non-intrusive and requires no special transparent window region. This is the first time this technique has been used in an electrically heated pressurized flow loop. This unique experimental method offers the opportunity to observe and record on videotape, flow patterns and transient behavior of two phase flow inside opaque containers without disturbing the environment. In this study the test sections consisted of stainless steel tubes with a 1.27 cm outer diameter and wall thicknesses of 0.084 cm and 0.124 cm. The experiments were carried out at the Pennsylvania State University 1 megawatt TRIGA reactor facility utilizing a Precise Optics neutron radiography camera. The inlet water temperature to the ...

1998-02-01

489

Vapor fraction measurements in a steam-water tube at up to 15 bar using neutron radiography techniques  

International Nuclear Information System (INIS)

Real-time neutron radiography has been used to study the dynamic behavior of two-phase flow and measure the time averaged vapor fraction in a heated metal tube containing boiling steam-water operating at up to 15 bar pressure. The neutron radiographic technique is non-intrusive and requires no special transparent window region. This is the first time this technique has been used in an electrically heated pressurized flow loop. This unique experimental method offers the opportunity to observe and record on videotape, flow patterns and transient behavior of two-phase flow inside opaque containers without disturbing the environment. In this study the test sections consisted of stainless steel tubes with a 1.27 cm outer diameter and wall thicknesses of 0.084 and 0.124 cm. The experiments were carried out at the Pennsylvania State University 1 MW TRIGA reactor facility utilizing a Precise Optics neutron radiography camera. The inlet water temperature to the test section ...

1999-11-03

490

Vapor fraction measurements in a steam-water tube at up to 15 bar using neutron radiography techniques  

International Nuclear Information System (INIS)

Real time neutron radiography has been used to study the dynamic behavior of two phase flow and measure the time averaged vapor fraction in a heated metal tube containing boiling steam water operating at up to 15 bar pressure. The neutron radiographic technique is non-intrusive and requires no special transparent window region. This is the first time this technique has been used in an electrically heated pressurized flow loop. This unique experimental method offers the opportunity to observe and record on videotape, flow patterns and transient behavior of two phase flow inside opaque containers without disturbing the environment. In this study the test sections consisted of stainless steel tubes with a 1.27 cm outer diameter and wall thicknesses of 0.084 cm and 0.124 cm. The experiments were carried out at the Pennsylvania State University 1 megawatt TRIGA reactor facility utilizing a Precise Optics neutron radiography camera. The inlet water temperature to the ...

1998-03-16

491

TFWT and OBT concentrations in rice plants exposed to HTO vapor during daytime and nighttime at different seed-developing stages  

Energy Technology Data Exchange (ETDEWEB)

Rice plants at different seed-developing stages were exposed to HTO vapor in an exposure box for 1 h during daytime and nighttime to investigate the levels of tissue free water {sup 3}H (TFWT) and organically bound {sup 3}H (OBT) in different plant parts. In the daytime experiment, TFWT concentrations in leaves at the end of exposure (h{sub 0}) were around 100% of the 1 hour mean HTO concentrations in air moisture whereas in the nighttime experiment, they were as low as 30{approx}40% of the air concentration. TFWT concentrations in both experiments decreased very rapidly in the beginning but much more slowly later and those at harvest were hundreds to hundred thousands times lower than those at h{sub 0}. OBT concentrations varied with time in different manners depending on plant parts and exposure times and differed between at h{sub 0} and at harvest by factors of less than 10 on the whole. Even during nighttime exposures, OBT was produced at about a third the rate ...

2003-03-15

492

Process feasibility study in support of silicon material, Task I. Quarterly technical progress report (XVIII), December 1, 1979-February 29, 1980  

Energy Technology Data Exchange (ETDEWEB)

Analyses of process system properties were continued for important chemical materials involved in the several processes under consideration for semiconductor and solar cell grade silicon production. Major activities were devoted to physical, thermodynamic and transport property data for silicon. Property data are reported for vapor pressure heat of vaporization, heat of sublimation, liquid heat capacity and solid heat capacity as a function of temperature to permit rapid usage in engineering. Chemical engineering analysis of the HSC process (Hemlock Semiconductor Corporation) for production of silicon was initiated. The process is based on hydrogen reduction of dichlorosilane (DCS) to produce the polysilicon. The chemical vapor deposition reaction for DCS is faster in rate than the conventional process route which utilizes trichlorosilane (TCS) as the silicon raw material. Status and progress are reported for primary ...

1980-03-01

493

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 on the newly measured transition ...

2003-11-07

494

Influence of phosphorus vapor ambient for InGaAsP growth on GaAs substrate  

Science.gov (United States)

For visible-light-emitting laser diodes, InGaAsP double heterostructures have been grown on GaAs substrates using liquid-phase epitaxy. As the growth temperature is as high as about 780 /sup 0/C, a large amount of phosphorus evaporates from the solutions for the cladding layers during the growth process. The phosphorus vapor disturbs the solution composition for the active layer, so that very thin and uniform active layers cannot be obtained. By using In-P-Sn solution and supplying the phosphorus partial pressure around the graphite boat, the influence of phosphorus vapor ambient for InGaAsP (lambda/sub P//sub L/ = 805 nm) growth is confirmed. When the phosphorus partial pressure increases, the surface of epitaxial layer becomes rough and the substrate is partly etched back. From x-ray diffraction and photoluminescence spectral measurements, the composition of the grown layer is also found to be changed. As a result of increasing the flow rate ...

1986-12-01

495

Cancer risks from soil emissions of volatile organic compounds at the Lawrence Livermore National Laboratory  

Energy Technology Data Exchange (ETDEWEB)

The emission isolation flux chamber (EIFC) methodology was applied to Superfund investigations at the Lawrence Livermore National Laboratory Site 300 to determine if on-site workers were exposed to VOCs volatilizing from the subsurface and what, if any, health risks could be attributed to the inhalation of the VOCs volatilizing from the subsurface. During July and August of 1996, twenty, eighteen, and twenty six VOC soil vapor flux samples were collected in the Building 830, 832, and 854 areas, respectively using EIFCS. The VOC concentrations in the vapor samples were used to calculate soil flux rates which were used as input into an air dispersion model to calculate ambient air exposure-point concentrations. The exposure-point concentrations were compared to EPA Region IX Preliminary Remediation Goals (PRGs). Buildings 830 and 832 exposure-point concentrations were less then the PRGs therefore no cancer risks were calculated. The cancer risks ...

1998-02-01

496

Adsorption of ethylene on graphitized thermal carbon black and in slit pores: a computer simulation study.  

Science.gov (United States)

In this paper, we studied vapor-liquid equilibria (VLE) and adsorption of ethylene on graphitized thermal carbon black and in slit pores whose walls are composed of graphene layers. Simple models of a one-center Lennard-Jones (LJ) potential and a two-center united atom (UA)-LJ potential are investigated to study the impact of the choice of potential models in the description of VLE and adsorption behavior. Here, we used a Monte Carlo simulation method with grand canonical Monte Carlo (GCMC) and Gibbs ensemble Monte Carlo ensembles. The one-center potential model cannot describe adequately the VLE over the practical range of temperature from the triple point to the critical point. On the other hand, the two-center potential model (Wick et al. J. Phys. Chem. B 2000, 104, 8008-8016) performs well in the description of VLE (saturated vapor and liquid densities and vapor pressure) over the wide range of temperature. This UA-LJ ...

2004-08-17

497

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 the vehicle. Either strategy results in a substantial heating load. These strategies ...

1996-09-01

498

Utility applications program. Annual report for 1981  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the Utility Applications Program is to provide information and assistance to interested utilities on central station energy storage systems. Compressed air and underground pumped hydroelectric energy storage are the primary technical focus. Smaller utilities are the primary targets of this program, as they may not have resources to track and utilize new energy conservation developments. The program, initiated during this year-long period, consists of a series of tasks integrating and supporting energy storage implementation. Program management and technical coordination activities monitor the wide range of research ongoing both under government support and in industry and provide a locus for dissemination of results. Recently completed DOE demonstration studies provide the central data base and the DOE CAES and UPH Technology Program activities provide another major resource. In addition a UPH preliminary feasibility study in coorination with Central ...

1982-06-01

499

Small-satellite technology and applications III  

Energy Technology Data Exchange (ETDEWEB)

This third conference on small-satellite applications has combined a number of significant and timely presentations on the status, in the US and on the international front, of this emerging industry. Presentations by all of the major Department of Defense activities in this field, including an overview of the ARPA CAMEO multispectral remote sensing satellite program, space activities at the Air Force Phillips Laboratory, and a space systems capabilities overview of the Naval Research Laboratory, are complemented by presentations from several international activities on their accomplishments and progress in the development of remote sensing satellite programs. For example: Spar Aerospace of Canada presented an overview of the progress they have made in establishing a space program through the use of small satellites, and the University of Surrey and Spar Aerospace provided an overview of the application of image compression schemes to imagery obtained from their ...

1993-01-01

500

Portable fluid X-ray diagnostic system  

Energy Technology Data Exchange (ETDEWEB)

A portable X-ray image system is described comprising: (a) a base assembly including panels and hinges joining the panels together along edges, and compression stops for biasing the hinges to compensate for the weight of payload when mounted on the base assembly, the compression stops being located for interaction with the hinges for biasing the panels to exhibit upward bowing when laid upon a flat surface prior to loading, and to provide resiliency for facilitating the base assembly assuming a substantially flat configuration when a predetermined payload is placed upon the base assembly; (b) an X-ray member; (c) apparatus for detachably mounting a table member to the base assembly to hold the table member at a location above the base; (d) an X-ray source; (e) means for sensing X-rays to form an image; (f) means for mounting the X-ray source and the X-ray sensing means on opposite sides relative to the table member and supported by the base ...

1989-02-14