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1

Evaporation system and method for gas jet deposition of thin film materials  

DOEpatents

A method and apparatus for depositing thin films of materials such as metals, oxides and nitrides at low temperature relies on a supersonic free jet of inert carrier gas to transport vapor species generated from an evaporation source to the surface of a substrate. Film deposition vapors are generated from solid film precursor materials, including those in the form of wires or powders. The vapor from these sources is carried downstream in a low pressure supersonic jet of inert gas to the surface of a substrate where the vapors deposit to form a thin film. A reactant gas can be introduced into the gas jet to form a reaction product with the evaporated material. The substrate can be moved from the gas jet past a gas jet containing a reactant gas in which a discharge has been generated, the speed of movement being sufficient to form a thin film which is chemically composed of the evaporated material and reactant gases.

Schmitt, Jerome J. (New Haven, CT); Halpern, Bret L. (Bethany, CT)

1994-01-01

2

Evaporation system and method for gas jet deposition of thin film materials  

DOEpatents

A method and apparatus are disclosed for depositing thin films of materials such as metals, oxides and nitrides at low temperature relies on a supersonic free jet of inert carrier gas to transport vapor species generated from an evaporation source to the surface of a substrate. Film deposition vapors are generated from solid film precursor materials, including those in the form of wires or powders. The vapor from these sources is carried downstream in a low pressure supersonic jet of inert gas to the surface of a substrate where the vapors deposit to form a thin film. A reactant gas can be introduced into the gas jet to form a reaction product with the evaporated material. The substrate can be moved from the gas jet past a gas jet containing a reactant gas in which a discharge has been generated, the speed of movement being sufficient to form a thin film which is chemically composed of the evaporated material and reactant gases. 8 figs.

Schmitt, J.J.; Halpern, B.L.

1994-10-18

3

A novel method to prepare carbon-coated quantum dots by an advanced gas evaporation method  

Microsoft Academic Search

Metallic quantum dots coated by amorphous carbon were produced by simultaneous evaporation of carbon and metal in Ar gas at 13 kPa. Carbon-coated Ag, Fe and Au dots with a size of 2–20 nm can be easily obtained. In the present experimental system, C60 crystals were also observed. The quantum dots included in C60 crystals have been indicated. The growth

Chihiro Kaito; Takemasa Sakamoto; Daisuke Ban; Takashi Izuta; Yasushi Kitano; Yoshio Saito

1996-01-01

4

Measurement of Vapor Distribution in Gas Evaporation without Convection by Atomic Absorption Method  

NASA Astrophysics Data System (ADS)

Measurement of the distribution of zinc vapor atoms is carried out by means of atomic light absorption spectroscopy in the top-heating gas evaporation furnace which is developed for the gas evaporation without convection on the ground. Distribution of supersaturated vapor atoms in the wide range from the evaporating surface in the gas atmosphere is measured. The sizes and number densities of collected particles at various places on the collecting rod are interpreted in terms of measured vapor densities and temperatures at respective places.

Sawai, Shinya; Dohi, Minoru; Kato, Manabu; Wada, Nobuhiko

1993-02-01

5

A Chinese liquor classification method based on liquid evaporation with one unmodulated metal oxide gas sensor  

Microsoft Academic Search

Electronic nose has been widely used in the classification of liquid samples, such as vinegars, wines and liquors, which have complex components. The difficulty of these classifications is how to get the information of the trace components in these samples. In this paper a method for liquor recognition based on liquid evaporation was presented. This method makes use of the

Qiong Zhou; Shunping Zhang; Yuxiao Li; Changsheng Xie; Huayao Li; Xiaohu Ding

6

Gas entrainment in an evaporating spray jet  

Microsoft Academic Search

Gas entrainment induced by a spray jet can be significantly affected by the spray evaporation rate. In this study, we have directly measured the air entrainment induced by a liquid nitrogen spray jet into an unbounded and stagnant room air. It is realized that the air entrainment is proportional to the axial gradient of oxygen mass flow in a pure

Muhammad Mushahid Rafique Qureshi; Chao Zhu

2006-01-01

7

Application of ZnO single-crystal wire grown by the thermal evaporation method as a chemical gas sensor for hydrogen sulfide.  

PubMed

A zinc oxide single-crystal wire was synthesized for application as a gas-sensing material for hydrogen sulfide, and its gas-sensing properties were investigated in this study. The gas sensor consisted of a ZnO thin film as the buffer layer and a ZnO single-crystal wire. The ZnO thin film was deposited over a patterning silicon substrate with a gold electrode by the CFR method. The ZnO single-crystal wire was synthesized over the ZnO thin film using zinc and activated carbon as the precursor for the thermal evaporation method at 800 degrees C. The electrical properties of the gas sensors that were prepared for the growth of ZnO single-crystal wire varied with the amount of zinc contained in the precursor. The charged current on the gas sensors increased with the increasing amount of zinc in the precursor. It was concluded that the charged current on the gas sensors was related to ZnO single-crystal wire growth on the silicon substrate area between the two electrodes. The charged current on the gas sensor was enhanced when the ZnO single-crystal wire was exposed to a H2S stream. The experimental results obtained in this study confirmed that a ZnO single-crystal wire can be used as a gas sensor for H2S. PMID:21446509

Park, N K; Lee, S Y; Lee, T J

2011-01-01

8

Apparatus and method for evaporator defrosting  

DOEpatents

An apparatus and method for warm-liquid defrosting of the evaporator of a refrigeration system. The apparatus includes a first refrigerant expansion device that selectively expands refrigerant for cooling the evaporator, a second refrigerant expansion device that selectively expands the refrigerant after the refrigerant has passed through the evaporator, and a defrosting control for the first refrigerant expansion device and second refrigerant expansion device to selectively defrost the evaporator by causing warm refrigerant to flow through the evaporator. The apparatus is alternately embodied with a first refrigerant bypass and/or a second refrigerant bypass for selectively directing refrigerant to respectively bypass the first refrigerant expansion device and the second refrigerant expansion device, and with the defrosting control connected to the first refrigerant bypass and/or the second refrigerant bypass to selectively activate and deactivate the bypasses depending upon the current cycle of the refrigeration system. The apparatus alternately includes an accumulator for accumulating liquid and/or gaseous refrigerant that is then pumped either to a refrigerant receiver or the first refrigerant expansion device for enhanced evaporator defrosting capability. The inventive method of defrosting an evaporator in a refrigeration system includes the steps of compressing refrigerant in a compressor and cooling the refrigerant in the condenser such that the refrigerant is substantially in liquid form, passing the refrigerant substantially in liquid form through the evaporator, and expanding the refrigerant with a refrigerant expansion device after the refrigerant substantially passes through the evaporator.

Mei, Viung C. (Oak Ridge, TN); Chen, Fang C. (Knoxville, TN); Domitrovic, Ronald E. (Knoxville, TN)

2001-01-01

9

Synthesis and magnetic properties of Fe2O3–TiO2 nano-composite particles using pulsed laser gas phase evaporation–liquid phase collecting method  

NASA Astrophysics Data System (ADS)

Fe2O3–TiO2 nano-composite particles were synthesized by a new method: pulsed laser gas phase evaporation–liquid phase collection. The targets are mixtures composed of 1%, 3%, 5%, 7% and 9% content micron-sized Fe2O3 powders each also mixed with micron-sized TiO2 powder. The morphology, structure, magnetic properties and synthesis mechanism of the samples were studied by means of transmission electron microscopy, X-ray diffraction, infrared spectroscopy, vibration magnetometer and other techniques. The results indicate that the Fe2O3–TiO2 nano-composite particles prepared with this new method are spherical, diameters of the primary particles range from 20 nm to 50 nm, and the particles have a tendency to form chain connections. All of the Fe2O3–TiO2 nano-composite particles contain TiO2 and Fe2O3 phases of both rutile and anatase crystal structures. With the addition of Fe2O3 content the magnetic saturation intensity and the coercivity both increase and the magnetic properties are obviously improved, the composite Fe2O3–TiO2 nanoparticles have added magnetic recovery functionality.

Chen, Suiyuan; Zhang, Yikun; Han, Weili; Wellburn, Daniel; Liang, Jing; Liu, Changsheng

2013-10-01

10

The Pristane Formation Index, a new molecular maturity parameter. A simple method to assess maturity by pyrolysis\\/evaporation-gas chromatography of unextracted samples  

Microsoft Academic Search

A set of eleven samples from the Handil borehole, Mahakam delta, Indonesia, has been analyzed to test the hypothesis that the Pristane Formation Index (PFI = [pristane]\\/{[pristane]+ [pristenes]}) can be used as a molecular maturation parameter. By pyrolysis\\/evaporation-gas chromatography (py\\/ev-GC) of unextracted samples the amounts of the product (pristane) and of the precursor(s) (measured as pristenes) of the pristane formation

H. Goossens; A. Due; J. W. de Leeuw; B. van de Graaf; P. A. Schenck

1988-01-01

11

Evaporation in Equilibrium, in Vacuum, and in Hydrogen Gas.  

National Technical Information Service (NTIS)

Evaporation experiments were conducted for SiO2 in three different conditions: in equilibrium, in vacuum, and in hydrogen gas. Evaporation rate in vacuum is about two orders of magnitude smaller than that in equilibrium, which is consistent with previous ...

H. Nagahara

1993-01-01

12

Measurement of the evaporation mass flow rate in a horizontal liquid layer partly opened into flowing gas  

NASA Astrophysics Data System (ADS)

The dynamics of evaporation from a local surface of a horizontal liquid layer under a gas flow is studied experimentally. The average evaporation mass flow rate of a liquid layer (HFE-7100) induced by inert gas (nitrogen) is measured using two independent methods. The influence of the average gas flow rate, gas and liquid temperature, and the layer depth upon the evaporation rate and convection in the liquid layer is investigated. Correlation dependences of the evaporation rate vs. the inert gas flow rate and temperature are obtained. It is found that the average evaporation-rate curve has a local maximum with a growth of the liquid layer depth. With the growth of the gas and liquid temperature, the local maximum in an evaporation flow rate of the liquid layer is shifted to the larger value of the liquid depth.

Lyulin, Yu. V.; Kabov, O. A.

2013-09-01

13

Optimum Method of Evaporator Pot Liquid Heating and Cooling for Evaporator Cleaning and Recovery Program  

SciTech Connect

The Savannah River Site Evaporators have run with limited operation problems for almost 40 years. In October 1999, one evaporator was shut down due to the inability to lift the concentrate solutions from the pot. Different methods of pot liquid heating, cooling, and selection of optimum method were discussed.

Kwon, K.C.

2001-05-02

14

Inlet Fogging of Gas Turbine Engines Detailed Climatic Analysis of Gas Turbine Evaporation Cooling Potential in the USA  

Microsoft Academic Search

Inlet fogging of gas turbine engines has attained considerable popularity due to the ease of installation and the relatively low first cost compared to other inlet cooling methods. With increasing demand for power and with shortages envisioned especially during the peak load times during the summers, there is a need to boost gas turbine power. There is a sizable evaporative

Mustapha Chaker; Cyrus B. Meher-Homji; Thomas Mee III; Alex Nicholson

2003-01-01

15

FIELD DEPLOYMENT EVALUATION OF THE FREEZE-THAW/EVAPORATION (FTE) PROCESS TO TREAT OIL AND GAS PRODUCED WATERS. Task 45. Final topical report.  

National Technical Information Service (NTIS)

TASK 45 FIELD DEPLOYMENT EVALUATION OF THE FREEZE THAW/ EVAPORATION (FTE ) PROCESS TO TREAT OIL AND GAS PRODUCED WATERS coupling evaporation with freezing. This offers operators a year- round method for treating produced water. Treating water with the FTE...

A. A. Grisanti J. A. Sorensen

1999-01-01

16

Evaporation  

NSDL National Science Digital Library

The representation is an animation of the water cycle. It shows water evaporating from a large body of water with a descriptive text describing the water cycle process including evaporation, condensation and precipitation. An additional diagram on transport is included.

17

Gas-assisted evaporative cooling of high density electronic modules  

Microsoft Academic Search

Gas-assisted evaporative cooling (GAEC), its advantages in thermal packaging of microelectronics, and its implementation in a prototype high-performance computer module, are described. Attention is then turned to theoretical considerations in the flow of gas-liquid-vapor mixtures in narrow, parallel plate channels, and to the design and operation of an appropriate experimental apparatus. Next, experimental results for the wall temperature, heat-transfer coefficients,

Avram Bar-Cohen; Greg Sherwood; Marc Hodes; Gary Solbreken

1995-01-01

18

Regulatory Off-Gas Analysis from the Evaporation of Hanford Simulated Waste Spiked with Organic Compounds  

SciTech Connect

After strontium/transuranics removal by precipitation followed by cesium/technetium removal by ion exchange, remaining low activity waste in the Hanford River Protection Project Waste Treatment Plant is to be concentrated by evaporation prior to being mixed with glass formers and vitrified. To provide a technical basis to permit the waste treatment facility, a relatively organic-rich Hanford Tank 241-AN-107 waste simulant was spiked with 14 target volatile, semi-volatile and pesticide compounds, and evaporated under vacuum in a bench-scale natural circulation evaporator fitted with an industrial stack off-gas sampler at the Savannah River Technology Center. An evaporator material balance for the target organics was calculated by combining liquid stream mass and analytical data with off-gas emissions estimates obtained using EPA SW-846 Methods. Volatile and light semi-volatile organic compounds in the waste simulant were found to largely exit through the condenser vent, while heavier semi-volatiles and pesticides generally remain in the evaporator concentrate. An OLI Environmental Simulation Program evaporator model successfully predicted operating conditions and the experimental distribution of the fed target organics exiting in the concentrate, condensate and off-gas streams with the exception of a few semi-volatile and pesticide compounds. Comparison with Henry's Law predictions suggests the OLI ESP model is constrained by available literature data.

Calloway, T.B. Jr.

2003-10-23

19

Evaporation  

NSDL National Science Digital Library

This three-part activity consists of an activity that groups of learners develop themselves, a given procedure, and an optional demonstration. First, learners discuss examples of evaporation and then design and conduct their own test to find out whether heating water has an effect on the rate of evaporation. While waiting for their results, learners conduct another evaporation activity using single drops of water on 2 paper towels, one of which is heated. The optional demonstration compares the rate of evaporation of hot and cold water using a sensitive scale or balance. In each of these experiences with evaporation, learners will identify variables, consider how to best control them, and use their observations to conclude that heating water increases the rate of evaporation.

Kessler, James H.; Galvan, Patricia M.

2007-01-01

20

Prediction of evaporating spray in anisotropically turbulent gas flow  

SciTech Connect

Numerical investigation was conducted for a confined evaporating isopropyl alcohol spray issuing into a coflowing, heated turbulent air stream. The Eulerian-Lagrangian stochastic model was used for the spray calculations. The gas phase turbulence was modeled using either the isotropic eddy viscosity model or the second-moment transport model for both Reynolds stresses and heat fluxes. Two droplet dispersion models were studied for the Lagrangian trajectory calculations: the conventional particle-eddy encounter model and the time-correlated dispersion model. In the time-correlated model, gas phase turbulent velocity fluctuations were correlated temporally and directionally between two successive time steps in modeling the droplet dispersion. The droplet evaporation was accounted for by the infinite-conduction evaporation model, where the gas-film variable properties were considered using the one-third rule. Detailed numerical results of the liquid droplet phase, i.e., the droplet mean diameters, mass fluxes, mean, and fluctuating velocities were presented and discussed by comparison with the experimental data. Results show that the droplet mean properties are generally not sensitive to the gas phase turbulence models and the droplet dispersion models, all of which can give agreeable predictions with the measurements except for the droplet mass fluxes, which accumulate persistently near the centerline for downstream in all calculations. It is found that the conventional particle-eddy encounter model fails to account for the anisotropy of droplet turbulence, no matter what turbulence model is used for the gas phase. The anisotropy of droplet phase turbulence, however, is well predicted by the time-correlated dispersion model in conjunction with the gas phase second-moment transport model.

Chen, X.Q.; Pereira, J.C.F. [Technical Univ. of Lisbon (Portugal)

1995-02-01

21

Evaporation Correction Methods for Microwave Retrievals of Surface Precipitation Rate  

Microsoft Academic Search

Active and passive microwave remote sensing esti- mates of surface precipitation based on signals from hydrometeors aloft require correction for evaporated precipitation that would otherwise reach the ground. This paper develops and compares two near-surface evaporation correction methods using two years of data from 509 globally distributed rain gauges and three passive millimeter-wave Advanced Microwave Sounding Units (AMSUs) aboard National

Chinnawat Surussavadee; David H. Staelin

2011-01-01

22

COMPONENT LOSS DURING EVAPORATION-RECONSTITUTION OF ORGANIC ENVIRONMENTAL SAMPLES FOR GAS CHROMATOGRAPHIC ANALYSIS  

EPA Science Inventory

Standard and sample solutions stored in borosilicate sample vials were allowed to evaporate to dryness at room temperature. The solutions were analyzed by gas chromatography-flame ionization detection before evaporation and after reconstitution to the original volume to determine...

23

Zno Nanostructures Grown By Thermal Evaporation And Thermal Decomposition Methods  

Microsoft Academic Search

We report on the growth of novel ZnO nanostructures using thermal evaporation and thermal decomposition methods. Thermal evaporation\\u000a is used to produce ZnO\\/carbon nanotubes heterostructures, while ZnO nanocrystals were produced by thermal decomposition of\\u000a zinc alginate gels. The nanostructures were characterized by a variety of techniques including x-ray diffraction, scanning\\u000a electron microscopy, Raman scattering, and photoluminescence spectroscopy. Semi-empirical molecular orbital

F. Kyriazis; S. N. Yannopoulos; A. Chrissanthopoulos; S. Baskoutas; N. Bouropoulos

24

Iodine129 process control monitor for evaporator off-gas streams  

Microsoft Academic Search

Continuous monitoring of gaseous ¹²⁹I in evaporator off-gas at nuclear fuel reprocessing facilities is important from both regulatory and process control viewpoints. Accordingly, continuous monitoring of evaporator overheads would supply the necessary information to retain ¹²⁹I in the evaporator bottoms should a process control mechanism for the evaporator be developed. Although a continuous ¹²⁹I monitor for nuclear fuel reprocessing plant

J. R. Burr; G. J. McManus

1984-01-01

25

Method and apparatus for flash evaporation of liquids  

DOEpatents

A vertical tube flash evaporator for introducing a superheated liquid into a flash evaporation chamber includes a vertical inlet tube with a flared diffuser portion at its upper outlet end. A plurality of annular screens are positioned in axially spaced-apart relation to each other around the periphery of the vertical tube and below the diffuser portion thereof. The screens are preferably curved upward in a cup-shaped configuration. These flash evaporators are shown in an ocean thermal energy conversion unit designed for generating electric power from differential temperature gradients in ocean water. The method of use of the flash evaporators of this invention includes flowing liquid upwardly through the vertical tube into the diffuser where initial expansion and boiling occurs quite violently and explosively. Unvaporized liquid sheets and drops collide with each other to enhance surface renewal and evaporation properties, and liquid flowing over the outlet end of the diffuser falls onto the curved screens for further surface renewal and evaporation.

Bharathan, Desikan (Lakewood, CO)

1984-01-01

26

Method and apparatus for flash evaporation of liquids  

SciTech Connect

A vertical tube flash evaporator for introducing a superheated liquid into a flash evaporation chamber includes a vertical inlet tube with a flared diffuser portion at its upper outlet end. A plurality of annular screens are positioned in axially spaced-apart relation to each other around the periphery of the vertical tube and below the diffuser portion thereof. The screens are preferably curved upward in a cup-shaped configuration. These flash evaporators are shown in an ocean thermal energy conversion unit designed for generating electric power from differential temperature gradients in ocean water. The method of use of the flash evaporators of this invention includes flowing liquid upwardly through the vertical tube into the diffuser where initial expansion and boiling occurs quite violently and explosively. Unvaporized liquid sheets and drops collide with each other to enhance surface renewal and evaporation properties, and liquid flowing over the outlet end of the diffuser falls onto the curved screens for further surface renewal and evaporation.

Bharathan, D.

1984-10-02

27

Method and apparatus for flash evaporation of liquids  

DOEpatents

A vertical tube flash evaporator for introducing a super-heated liquid into a flash evaporation chamber includes a vertical inlet tube with a flared diffuser portion at its upper outlet end. A plurality of annular screens are positioned in axially spaced-apart relation to each other around the periphery of the vertical tube and below the diffuser portion thereof. The screens are preferably curved upward in a cup-shaped configuration. These flash evaporators are shown in an ocean thermal energy conversion unit designed for generating electric power from differential temperature gradients in ocean water. The method of use of the flash evaporators of this invention includes flowing liquid upwardly through the vertical tube into the diffuser where initial expansion and boiling occurs quite violently and explosively. Unvaporized liquid sheets and drops collide with each other to enhance surface renewal and evaporation properties, and liquid flowing over the outlet end of the diffuser falls onto the curved screens for further surface renewal and evaporation.

Bharathan, D.

1984-01-01

28

Limits to sympathetic evaporative cooling of a two-component Fermi gas  

Microsoft Academic Search

We find a limit cycle in a quasiequilibrium model of evaporative cooling of a two-component trapped fermion gas. The existence of such a limit cycle represents an obstruction to reaching the quantum ground state evaporatively. We show that evaporatively betamu~O(1). We speculate that one may be able to cool an atomic Fermi gas further by photoassociating dimers near the bottom

M. Crescimanno; C. G. Kaoy; R. Peterson

2000-01-01

29

Surface and gas-phase resistances to the evaporation of droplets.  

PubMed

Attempt has been made to asses quantitatively the magnitudes of both the gas-phase resistance and the surface resistance to the evaporation of droplets and to determine the transition point at which the evaporation changes from a diffusion-controlled to a surface-controlled process. This transition point is strongly dependent upon the ambient pressure and the droplet size. It is found that at atmospheric pressure the particle radius at which the transition takes place is in the range of 1 - 10mu for water, 0.1mu for n-dibutylphthalate, 0.1 - 1.0mu for mercury, and 0.001mu for liquid helium. Furthermore, we have found that the surface resistance and the gas-phase resistance vary with the size of the droplet in opposite direction, leading to the existence of a maximum rate of evaporation at a certain value of the droplet radius, this radius being dependent upon the characteristics of the liquid concerned. This conclusion may be useful in the search for an optimum and most efficient method of combustion of fuel sprays in automotive engines, gas turbines, and oil-burning power plants. PMID:1149699

Zung, J T

1975-01-01

30

Performance improvement of a gas turbine cycle by using a desiccant-based evaporative cooling system  

Microsoft Academic Search

This paper focuses on power augmentation of a typical gas turbine cycle by using a desiccant-based evaporative cooling system. This technique requires a desiccant-based dehumidifying process be used to direct the air through an evaporative cooler, which could be either media-based or spray type. This could assist the evaporative cooling cycle to make necessary adjustment for any possible installation defects

Amir Abbas Zadpoor; Ali Hamedani Golshan

2006-01-01

31

Thermal design method of bayonet-tube evaporators and condensers  

Microsoft Academic Search

The paper describes an effectiveness-NTU design method of bayonet-tube evaporators and condensers. Including the effect of the wall superheat on the shell-side film coefficient, and using an energy balance on the tube, differential equations for the steady-state fluid temperatures are formulated. Because of the nonlinear nature of the governing equations, the fourth-order Runge-Kutta method is employed to the solution of

N Kayansayan

1996-01-01

32

Severe Local Hypothermia from Laparoscopic Gas Evaporative Jet Cooling: A Mechanism To Explain Clinical Observations  

PubMed Central

Background and Objectives: Explanations for laparoscopic-induced hypothermia fail to explain clinical observations. It is possible that water evaporation occurs from the jet stream of gas inflation resulting in tissue surface super-cooling leading to tissue damage and drying. Methods: Theoretical calculations based on thermal conductivity, mass transfer effects and heat flux considerations correlated closely with synthetic and tissue experiments. Thermocouple measurements at a rate of 15 data points per second were performed. Results: Cooling rates of 10 to 25 degrees centigrade per second for high flow rates were found based on gas flow rate and effective size of gas delivery site. These rapid temperature drops extended beyond a 2 cm2 diameter. Conclusions: Evaporative cooling accounts for significant hypothermia. The cooling is dependent on the lack of water vapor in the gases currently used during laparoscopy. Cooling rates are independent of height from tissue and geometry of delivery port. Heating and hydrating the gas to a physiologic condition eliminates hypothermia and tissue dessication.

Gray, Robert I.; Henderson, A. Courtney; Cochran, Steve A.; Roth, Elizabeth A.

1999-01-01

33

Flash gas bypass for improving the performance of transcritical R744 systems that use microchannel evaporators  

Microsoft Academic Search

The performance of transcritical R744 systems with direct expansion (DX) can be significantly improved by implementing a Flash Gas Bypass (FGB). The idea behind the concept is to bypass refrigerant vapor, created during the isenthalpic expansion process, around the evaporator. By feeding the evaporator with liquid refrigerant, pressure drop is reduced and refrigerant distribution is improved. With R744 as the

Stefan Elbel; Pega Hrnjak

2004-01-01

34

Characterization of Bismuth Telluride thin films — Flash evaporation method  

Microsoft Academic Search

Semiconducting Bi2Te3 thin films were grown by a flash evaporation method. The optical characteristics of Bi2Te3 samples have been analyzed using a spectrophotometer in the wavelength range of 400–800 nm. The transmittance falls steeply with decreasing wavelength. It reveals that Bi2Te3 films have considerable absorption throughout the wavelength region. The effect of thickness on the fundamental optical parameters like refractive index

J. Dheepa; R. Sathyamoorthy; S. Velumani

2007-01-01

35

Results for the DWPF Slurry Mix Evaporator Condensate Tank, Off Gas Condensate Tank, And Recycle Collection Tank Samples  

SciTech Connect

The Defense Waste Processing Facility, DWPF, currently generates approximately 1.4 million gallons of recycle water per year during Sludge-Only operations. DWPF has minimized condensate generation to 1.4 million gallons by not operating the Steam Atomized Scrubbers, SASs, for the melter off gas system. By not operating the SASs, DWPF has reduced the total volume by approximately 800,000 gallons of condensate per year. Currently, the recycle stream is sent to back to the Tank Farm and processed through the 2H Evaporator system. To alleviate the load on the 2H Evaporator system, an acid evaporator design is being considered as an alternate processing and/or concentration method for the DWPF recycle stream. In order to support this alternate processing option, the DWPF has requested that the chemical and radionuclide compositions of the Off Gas Condensate Tank, OGCT, Slurry Mix Evaporator Condensate Tank, SMECT, Recycle Collection Tank, RCT, and the Decontamination Waste Treatment Tank, DWTT, be determined as a part of the process development work for the acid evaporator design. Samples have been retrieved from the OGCT, RCT, and SMECT and have been sent to the Savannah River National Laboratory, SRNL for this characterization. The DWTT samples have been recently shipped to SRNL. The results for the DWTT samples will be issued at later date.

TERRI, FELLINGER

2004-12-21

36

Evaporation and Condensation of Large Droplets in the Presence of Inert Admixtures Containing Soluble Gas  

Microsoft Academic Search

In this study the mutual influence of heat and mass transfer during gas absorption and evaporation or condensation on the surface of a stagnant droplet in the presence of inert admixtures containing noncon- densable soluble gas is investigated numerically. The performed analysis is pertinent to slow droplet evapo- ration or condensation. The system of transient conjugate nonlinear energy and mass

T. Elperin; A. Fominykh; B. Krasovitov

2007-01-01

37

Liquid film and gas flow motion in a microchannel with evaporation  

NASA Astrophysics Data System (ADS)

The problem of stabilized combined motion of the gas flow and liquid film in a microchannel under the action of local heating with consideration of evaporation processes was set in selected variables. The exact solutions to the linearized problem were derived. The analytical formulas for calculation of the film thickness stabilized below the heater and the total rate of liquid evaporation were obtained. The technique of approximate calculation of total heat transfer is shown. Exemplary calculations are presented.

Kuznetsov, V. V.; Andreev, V. K.

2013-03-01

38

Methods of gas analysis  

SciTech Connect

Methods for sampling, calibrating, and analyzing for helium, impurities in helium, and natural gases are described. These methods were developed by the US Bureau of Mines to assist in the processing of natural gas for helium recovery. 35 refs.

Emerson, D.E. (Bureau of Mines, Amarillo, TX (United States))

1993-01-01

39

Comparison of different methods for estimating soil surface evaporation in a bare field  

NASA Astrophysics Data System (ADS)

In this paper, three methods for estimating soil evaporation in a bare field were evaluated: evaporation ratio method ( k ratio), complementary relationship and bulk equation. Micro-lysimeters were used to measure the actual evaporation for validation of the three methods. For the k ratio method, pan evaporation was used as the reference evaporation instead of the value obtained from the Penman-Monteith equation. This result is important for areas where meteorological data are unavailable. The results showed that, for daytime evaporation, the k ratio and bulk equation produced a good fit with the observation data, while the complementary relationship generated a larger deviation from the measured data. We recommend that the k ratio method and bulk equation could be used to calculate daytime soil evaporation with high accuracy when soil water content and pan evaporation data or meteorological data are available, while the complementary relationship could be used for a rough estimation when pan evaporation is available. All the methods could be applied to calculate cumulative evaporation.

Yan, Haofang; Zhang, Chuan; Oue, Hiroki; Sugimoto, Hideki

2012-11-01

40

Electron Beam Evaporation of Tungsten Oxide Films for Gas Sensors  

Microsoft Academic Search

Pure and iron incorporated nanostructured Tungsten Oxide (WO3) thin films were investigated for gas sensing applications using noise spectroscopy. The WO3 sensor was able to detect lower concentrations (1-10 ppm) of NH3, CO, CH4, and Acetaldehyde gases at operating temperatures between 100°C to 250°C. The iron-doped Tungsten Oxide sensor ( WO3:Fe) showed some response to Acetaldehyde gas at relatively higher

T. Tesfamichael

2010-01-01

41

Comparison of Total Evaporation (TE) and Direct Total Evaporation (DTE) methods in TIMS by using NBL CRMs  

NASA Astrophysics Data System (ADS)

The total evaporation (TE) is a well-established analytical method for safeguards measurement of uranium and plutonium isotope-amount ratios using the thermal ionization mass spectrometry (TIMS). High accuracy and precision isotopic measurements find many applications in nuclear safeguards, for e.g. assay measurements using isotope dilution mass spectrometry. To achieve high accuracy and precision in TIMS measurements, mass dependent fractionation effects are minimized by either the measurement technique or changes in the hardware components that are used to control sample heating and evaporation process. At NBL, direct total evaporation (DTE) method on the modified MAT261 instrument, uses the data system to read the ion signal intensity and its difference from a pre-determined target intensity, is used to control the incremental step at which the evaporation filament is heated. The feedback and control is achieved by proprietary hardware from SPECTROMAT that uses an analog regulator in the filament power supply with direct feedback of the detector intensity. Compared to traditional TE method on this instrument, DTE provides better precision (relative standard deviation, expressed as a percent) and accuracy (relative difference, expressed as a percent) of 0.05 to 0.08 % for low enriched and high enriched NBL uranium certified reference materials.

Hasözbek, Altug; Mathew, Kattathu; Wegener, Michael

2013-04-01

42

Evaporation determined by the energy-budget method for Mirror Lake, New Hampshire  

USGS Publications Warehouse

Evaporation was determined by the energy-budget method for Mirror Lake during the open water periods of 1982-1987. For all years, evaporation rates were low in spring and fall and highest during the summer. However, the times of highest evaporation rates varied during the 6 yr. Evaporation reached maximum rates in July for three of the years, in June for two of the years, and in August for one of the years. The highest evaporation rate during the 6-yr study was 0.46 cm d-1 during 27 May-4 June 1986 and 15-21 July 1987. Solar radiation and atmospheric radiation input to the lake and long-wave radiation emitted from the lake were by far the largest energy fluxes to and from the lake and had the greatest effect on evaporation rates. Energy advected to and from the lake by precipitation, surface water, and ground water had little effect on evaporation rates. In the energy-budget method, average evaporation rates are determined for energy-budget periods, which are bounded by the dates of thermal surveys of the lake. Our study compared evaporation rates calculated for short periods, usually ???1 week, with evaporation rates calculated for longer periods, usually ???2 weeks. The results indicated that the shorter periods showed more variability in evaporation rates, but seasonal patterns, with few exceptions, were similar.

Winter, T. C.; Buso, D. C.; Rosenberry, D. O.; Likens, G. E.; Sturrock, Jr. , A. M.; Mau, D. P.

2003-01-01

43

Investigation of Heat and Mass Transfer in the Evaporation of Liquid in a Forced Gas Stream.  

National Technical Information Service (NTIS)

This report presents results of an experimental study of the mechanism of heat and mass transfer in the interaction of fluid and moist bodies with a gas stream. In the first series of experiments, evaporation of water, acetone, benzene, and butanol from a...

G. T. Sergeev

1964-01-01

44

Surface-tension-driven instabilities of a pure liquid layer evaporating into an inert gas  

Microsoft Academic Search

A theoretical model of the evaporation of a pure liquid layer is developed. We focus on the influence of an inert gaseous component, in addition to vapor, on surface-tension-driven Bénard instabilities. It is assumed that the gas phase is perfectly mixed at some distance from the liquid–gas interface (given composition, pressure, and temperature). If this distance is not much larger

Benoît Haut; Pierre Colinet

2005-01-01

45

Synthesis and characterization of indium tin oxide (ITO) nanoparticle using gas evaporation process  

Microsoft Academic Search

In this paper, indium tin oxide (ITO) nanoparticle was synthesized by gas evaporation process, and its physical properties\\u000a such as particle size, specific surface area, crystal structure, and composition ratio according to the heat-treating conditions\\u000a were investigated to optimize them. The source material was charged in a chamber with vacuum circumstance of 110?5 torr, and the oxygen gas was supplied

Sung-Jei Hong; Jeong-In Han

2006-01-01

46

Simulation and Optimization of Evaporative Gas Turbine with Chemical Absorption for Carbon Dioxide Capture  

Microsoft Academic Search

This article studied the integration of an evaporative gas turbine (EvGT) cycle with chemical absorption for CO2 capture. Two systems of EvGT cycle without CO2 capture and EvGT cycle with CO2 capture were simulated and optimized. The impacts of key parameters such as the water\\/air ratio (W\\/A), the stripper pressure, and the flue-gas condensing temperature were studied regarding the electrical

H. Li; S. Flores; Y. Hu; J. Yan

2009-01-01

47

Oxygen Isotopic Fractionation During Evaporation of SiO2 in Vacuum and in H Gas  

NASA Astrophysics Data System (ADS)

Chondritic components, chondrules, CAIs, and some parts of the matrix are believed to have formed and/or thermally processed in the solar nebula. If this scenario is the case, they should be fractionated for major and minor elements and isotopes according to the formation temperature. This is true for major and trace elements, but is not the case for isotopes. Differences in oxygen isotopic composition among meteorite groups are interpreted to be the results of mixing of gas and dust from different oxygen reservoirs, and the effect of isotopic fractionation is negligible for most meteorites except for rare CAIs. Davis et al. [1] studied the isotopic fractionation of SiO2, MgO, and forsterite and showed that oxygen isotopic fractionation from solid materials is very small, but that from liquid is significant. Evaporation in the solar nebula should, however, be in hydrogen gas, which is reactive with silicates. Therefore, the effect of hydrogen gas on the evaporation behaviors of silicates, including mode of evaporation, evaporation rate, and compositional and isotopic fractionation, should be studied. Nagahara [2] studied the evaporation rate of SiO2 in equilibrium, in constant evacuation (free evaporation), and in hydrogen, and showed that the rate in hydrogen gas is orders of magnitude larger than that in vacuum; the mode of evaporation also differs from that in vacuum. Oxygen isotopic fractionation during evaporation of SiO2 in constant evacuation and in hydrogen gas at two different total pressures are studied in the present study. The starting material is a single crystal of natural quartz, which should transform into high cristobalite at experimental conditions. The powdered starting material was kept in a graphite capsule without a cap and set in a vacuum chamber with and without hydrogen gas flow. Experimental temperature was 1600 degrees C. Oxygen isotopic compositions (^18O/^16O) were measured with the CO2laser heating fluorination technique. Oxygen isotope measurements, including ^17O and silicon isotope measurements, are now in progress, and some of the results are shown in this paper. Oxygen isotopic compositions of residues in vacuum and in hydrogen gas of total pressure of 2.6 x 10^-5 bar, which approximates the pressure of the solar nebula at the midplane at 2-3 AU, are shown in comparison with evaporation rate (Figs. 1 and 2). Oxygen isotopic fractionation is remarkable in a constant evacuation, but is negligible in hydrogen gas of 2.6 x 10^-5 bar total pressure. In vacuum, delta ^18O of solid residue increases with increasing degree of evaporation. The curve is best fit to delta ^18O = 0.00094x^2 + 0.00173x + 19.606 (r = 0.997), where x is the degree of evaporation in weight percent. The curve is fit to the Rayleigh fractionation curve with a constant fractionation factor (alpha(sub)vap-sol) of 0.9970. Figures 1 and 2 show that evaporation is significant but oxygen isotopic fractionation is insignificant in hydrogen gas in the approximate solar nebular condition. The high evaporation rate in hydrogen gas is due to the fact that evaporation is a decomposition reaction of an oxide, which should be accelerated in reducing condition. The rate, however, can be explained by an unknown diffusion process that is possible when hydrogen is reactive with silica [2]. In a fairly high hydrogen pressure, isotopic fractionation is suppressed. On the other hand, in vacuum, the evaporation rate is small but the degree of isotopic fractionation is significant. The results suggest that chondrules and CAIs without isotopic mass fractionation could have been formed in the solar nebula, but that mass loss during heating should have been significant. The CAIs with significant mass fractionation such as HAL could have been formed in vacuum. References: [1] Davis A. et al. (1990) Nature, 347, 655-658. [2] Nagahara H. (1993) LPS XXIV, 1045-1046. Fig. 1, which appears here in the hard copy, shows the evaporation rate of SiO2 heated at 1600 degrees C in vacuum and in hydrogen gas of 2.6 x 10^-5 bar as a function of time. Fig. 2, wh

Nagahara, H.; Young, E. D.; Hoering, T. C.; Mysen, B. O.

1993-07-01

48

Evaporation from Nonvegetated Surfaces: Surface Aridity Methods and Passive Microwave Remote Sensing  

Microsoft Academic Search

The use of remotely sensed near-surface soil moisture for the estimation of evaporation is investigated. Two widely used parameterizations of evaporation, the so-called a and b methods, which use near-surface soil moisture to reduce some measure of potential evaporation, are studied. The near-surface soil moisture is provided by a set of L- and S-band microwave radiometers, which were mounted 13

ANTHONY T. C AHILL; MARC B. PARLANGE; THOMAS J. JACKSON

1998-01-01

49

Fuel oil evaporation in swirling hot gas streams  

Microsoft Academic Search

As the limit on combustion generated pollutants is becoming more strict, a potentially ecological as well as economical new technology to decrease combustion generated pollutants by liquid fuel combustion is to adopt a fuel pre-vaporized, premixed combustion. This paper presents a study on the liquid fuel vaporizing and mixing processes. An effective method for the calculation of turbulent two phase

Baifang Zuo; E. Van Den Bulck

1998-01-01

50

Evaporation and heating of a single suspended coal-water slurry droplet in hot gas streams  

SciTech Connect

The evaporation, heating, and burning of single coal-water slurry droplets are studied. The coal selected in this study is Pittsburgh Seam number 8 coal which is a medium volatile caking bituminous coal. The droplet is suspended on a microthermocouple and exposed to a hot gas stream. Temperature measurement and microscopic observation are performed in the parametric studies. The duration of water evaporation in CWS droplets decreases with the reduction of the droplet size, increasing of coal weight fraction, and increasing of gas temperature and velocity. The duration of heat-up is always significant due to the agglomeration. The CWS droplets are generally observed to swell like popcorn during heating. A model for the formation of the popped swelling is proposed and discussed.

Shi-chune, Y.; Liu, L.

1982-01-01

51

Evaporative depolarization and spin transport in a unitary trapped Fermi gas  

SciTech Connect

We consider a partially spin-polarized atomic Fermi gas in a high-aspect-ratio trap, with a flux of predominantly spin-up atoms exiting the center of the trap. We argue that such a scenario can be produced by evaporative cooling, and we find that it can result in a substantially nonequilibrium polarization pattern for typical experimental parameters. We offer this as a possible explanation for the quantitative discrepancies in recent experiments on spin-imbalanced unitary Fermi gases.

Parish, Meera M. [Department of Physics, Princeton University, Princeton, New Jersey 08544 (United States); Princeton Center for Theoretical Science, Princeton University, Princeton, New Jersey 08544 (United States); Huse, David A. [Department of Physics, Princeton University, Princeton, New Jersey 08544 (United States)

2009-12-15

52

Buffer gas loading and evaporative cooling in the multi-partial-wave regime  

Microsoft Academic Search

This thesis describes the study of collisions in the multi-partial-wave regime relevant to the buffer gas cooling and trapping of atoms. A quantitative model is formulated to describe the dynamics of evaporative cooling and is used to infer elastic and inelastic collision rate constants of g el = 2.15(+2.5, -1.2) x 10-10 cm 3\\/s and gin = 1.36(+1.2, -0.7) x

Scott Vinh Nguyen

2006-01-01

53

SET UP AND OPERATION OF A RECIRCULATING WETTED RIGID MEDIA EVAPORATIVE COOLER INSTALLED IN A GAS TURBINE COMBUSTION INLET AIR SYSTEM  

Microsoft Academic Search

A procedure for setting up and operating a recirculating evaporative cooler installed in the combustion air inlet system of a gas turbine is described. The procedure includes a recommendation for selecting the ambient operating wet and dry bulb temperatures. A description of the parameters used in the procedure and calculation methods are shown. In response to frequent inquiries about the

R. S. Johnson

54

Non-Absorbable Gas Behavior in the Absorber/Evaporator of a Absorption Chiller  

NASA Astrophysics Data System (ADS)

A two-dimensional numerical study on non-absorbable gas behavior in the absorber/evaporator of an absorption chiller has been performed. In the present study, the effect of the pitch-to-diameter ratio of a cylinder bundle in the absorber was highlighted. From the results, a sudden decrease of the overall heat transfer coefficient of the absorber was observed at a certain mean concentration of non-absorbable gas for each pitch-to-diameter ratio. Such a critical concentration was also found to decrease as the pitch-to- diameter ratio increased. The sudden decrease occurs due to the sudden disappearance of recirculating region, which is formed between the absorber and the evaporator, and where most of non-absorbable gas stays when it exists. As the pitch-to-diameter ratio increases, the recirculating region becomes weak because the velocity of the high velocity region supporting the recirculating flow decreases. Then, the critical mean concentration of non-absorbable gas is found to decrease as pitch-to-ratio increases.

Suzuki, Hiroshi; Nagamoto, Wataru; Sugiyama, Takahide

55

Enhancement and simplification of EBIS operation by evaporative ion cooling through gas mixing  

SciTech Connect

The stepwise ionization in EBIS sources can be extended beyond th time at which neutralization of the electron beam space charge is reached by trapping ions from the residual gas: We have added minor amounts of argon to the residual gas in the main trap. From this gas mixture ions are formed during the whole containment time and extracted to a TOF analyser. At short containment times, the amount and the charge states of the residual gas ions increase with time [minus] no argon seems to be present. At long containment times, argon ions dominate the spectrum more and more and increase their charge state according to time, while the total amount of charges does not increase further. The transition occurs, when the containment time equals the time, where a maximum of ions is collected. Then evaporative cooling of argon ions by residual gas ions is starting, ending at long containment times in a stationary state, where most of the residual gas ions are lost radially.

Becker, R.; Kleinod, M.; Thomae, H. (Institut fuer Angewandte Physik der Universitaet Frankfurt/M (Germany)); Donets, E.D. (JINR, Dubna, Moscow Region (Russian Federation))

1993-06-05

56

A comparative study on the estimation of evapotranspiration using backpropagation neural network: Penman–Monteith method versus pan evaporation method  

Microsoft Academic Search

The study compares the prediction performances of evapotranspiration by the FAO56 Penman–Monteith method and the pan evaporation\\u000a method using the artificial neural network. A backpropagation neural network was adopted to determine the relationship between\\u000a meteorological factors and evapotranspiration or evaporation. The evapotranspiration in the ChiaNan irrigated area of Tainan\\u000a was considered. Weather data compiled by Irrigation Experiment Station of ChiaNan

Sheng-Feng Kuo; Feng-Wen Chen; Pei-Yu Liao; Chen-Wuing Liu

57

Comparison of 15 evaporation methods applied to a small mountain lake in the northeastern USA  

USGS Publications Warehouse

Few detailed evaporation studies exist for small lakes or reservoirs in mountainous settings. A detailed evaporation study was conducted at Mirror Lake, a 0.15 km2 lake in New Hampshire, northeastern USA, as part of a long-term investigation of lake hydrology. Evaporation was determined using 14 alternate evaporation methods during six open-water seasons and compared with values from the Bowen-ratio energy-budget (BREB) method, considered the standard. Values from the Priestley-Taylor, deBruin-Keijman, and Penman methods compared most favorably with BREB-determined values. Differences from BREB values averaged 0.19, 0.27, and 0.20 mm d-1, respectively, and results were within 20% of BREB values during more than 90% of the 37 monthly comparison periods. All three methods require measurement of net radiation, air temperature, change in heat stored in the lake, and vapor pressure, making them relatively data intensive. Several of the methods had substantial bias when compared with BREB values and were subsequently modified to eliminate bias. Methods that rely only on measurement of air temperature, or air temperature and solar radiation, were relatively cost-effective options for measuring evaporation at this small New England lake, outperforming some methods that require measurement of a greater number of variables. It is likely that the atmosphere above Mirror Lake was affected by occasional formation of separation eddies on the lee side of nearby high terrain, although those influences do not appear to be significant to measured evaporation from the lake when averaged over monthly periods. ?? 2007 Elsevier B.V. All rights reserved.

Rosenberry, D. O.; Winter, T. C.; Buso, D. C.; Likens, G. E.

2007-01-01

58

Development and testing of a method for efficient simulation of evaporation from a seepage face  

SciTech Connect

Evaporation from the surface of a porous medium is a complex process, governed by interplay between (1) coupled liquid and vapor flow in the porous medium, and (2) relative humidity, temperature, and aerodynamic conditions in the surrounding air. In order to avoid the computational expense of explicitly simulating liquid, gas, and heat flow in the porous medium (and the possible further expense of simulating the flow of water vapor in the atmosphere), evaporative potentials can be treated in a simplified manner within a model where liquid is the only active phase. In the case of limited air mixing, evaporation can be approximated as a diffusion process with a linear vapor-concentration gradient. We have incorporated a simplified scheme into the EOS9 module of iTOUGH2 to represent evaporation as isothermal Fickian diffusion. This is notable because the EOS9 module solves a single equation describing saturated and unsaturated flow, i.e., phase transitions and vapor flow are not explicitly simulated. The new approach was applied to three simple problems and the results were compared to those obtained with analytical solutions or the EOS4 module, which explicitly considers advective and diffusive vapor flow. Where vapor flow within the porous medium can be neglected, this new scheme represents significant improvement over the computational expense of explicitly simulating liquid, gas, and heat flow, while providing an adequate reproduction of the overall hydrologic system. The scheme is set up to allow parallel flow of liquid and vapor, so that evaporation from an actively seeping face can be simulated. In addition, dynamic relative humidity boundary conditions can be simulated using standard iTOUGH2 features.

Ahlers, C. Fredrik; Ghezzehei, Teamrat; Finsterle, Stefan

2003-05-12

59

Trace gas exchange above the floor of a deciduous forest: 1. Evaporation and CO2 efflux  

Microsoft Academic Search

The eddy correlation method has great potential for directly measuring trace gas fluxes at the floor of a forest canopy, but a thorough validation study has not been yet conducted. Another appeal of the eddy correlation method is its ability to study processes that regulate and modulate gas exchange between the soil\\/litter complex and the atmosphere that cannot be probed

Dennis D. Baldocchi; Tilden P. Meyers

1991-01-01

60

Biodegradable, somatostatin acetate containing microspheres prepared by various aqueous and non-aqueous solvent evaporation methods  

Microsoft Academic Search

Somatostatin, a therapeutic peptide drug, was entrapped within polymeric microspheres made from high molecular weight poly (d,l-lactide\\/glycolide) (PLGA) or low molecular weight poly (d,l-lactide) (PLA) by various modifications of the O\\/W-solvent evaporation method. The drug was either dispersed as solid (dispersion method), dissolved with the aid of a co-solvent (co-solvent method) or emulsified as an aqueous solution (W\\/O\\/W-multiple emulsion method)

Joachim Herrmann; Roland Bodmeier

1998-01-01

61

Improvement in the Estimations of Potential Evaporation by the Temperature Method Using Regional Coefficients  

NASA Astrophysics Data System (ADS)

The Penman's potential evaporation is often utilized instead of pan evaporation. It, however, requires the meteorological data such as air temperature, humidity, wind speed, and sunshine duration. Therefore, it is inconvenient for its application in developing countries where there is an insufficient amount of meteorological data. The temperature method such as the Hamon and Thornthwaite equations is convenient because they need only air temperature. In this study, the two regional coefficients were newly determined in the Hamon and Thornthwaite equations to fit the Penman's potential evaporation, and the accuracy of the estimations by those equations were investigated. The results showed that the accuracy was best when the estimations were made with the coefficients which depend on each locality, and that the accuracy was further improved with the coefficients which depend on each climatological zone.

Moroizumi, Toshitsugu; Komura, Takuya; Miura, Takeshi

62

Annatto Polymeric Microparticles: Natural Product Encapsulation by the Emulsion-Solvent Evaporation Method  

ERIC Educational Resources Information Center

|In this experiment, the extract from annatto seeds was encapsulated in poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) particles by the emulsion-solvent evaporation method. The particles were washed and centrifuged to remove excess stabilizer and then freeze-dried. The main compound of annatto seeds, bixin, has antioxidant properties as well…

Teixeira, Zaine; Duran, Nelson; Guterres, Silvia S.

2008-01-01

63

Screening of anthropogenic compounds in polluted sediments and soils by flash evaporation\\/pyrolysis gas chromatography-mass spectrometry  

Microsoft Academic Search

The use of flash evaporation and pyrolysis gas chromatography-mass spectrometry as a fast screening procedure for anthropogenic substances in environmental samples is demonstrated by the analysis of polluted soil and sediment samples. Polycyclic aromatic hydrocarbons, haloorganics, aliphatic hydrocarbons, heteroaromatics, elemental sulfur, cyanides, and pyrolysis products of synthetic polymers are among the anthropogenic substances that can be readily detected by this

J. W. de Leeuw; E. W. B. de Leer; J. S. Sinninghe. Damste; P. J. W. Schuyl

1986-01-01

64

Estimation of evaporation from open water - A review of selected studies, summary of U.S. Army Corps of Engineers data collection and methods, and evaluation of two methods for estimation of evaporation from five reservoirs in Texas  

USGS Publications Warehouse

Organizations responsible for the management of water resources, such as the U.S. Army Corps of Engineers (USACE), are tasked with estimation of evaporation for water-budgeting and planning purposes. The USACE has historically used Class A pan evaporation data (pan data) to estimate evaporation from reservoirs but many USACE Districts have been experimenting with other techniques for an alternative to collecting pan data. The energy-budget method generally is considered the preferred method for accurate estimation of open-water evaporation from lakes and reservoirs. Complex equations to estimate evaporation, such as the Penman, DeBruin-Keijman, and Priestley-Taylor, perform well when compared with energy-budget method estimates when all of the important energy terms are included in the equations and ideal data are collected. However, sometimes nonideal data are collected and energy terms, such as the change in the amount of stored energy and advected energy, are not included in the equations. When this is done, the corresponding errors in evaporation estimates are not quantifiable. Much simpler methods, such as the Hamon method and a method developed by the U.S. Weather Bureau (USWB) (renamed the National Weather Service in 1970), have been shown to provide reasonable estimates of evaporation when compared to energy-budget method estimates. Data requirements for the Hamon and USWB methods are minimal and sometimes perform well with remotely collected data. The Hamon method requires average daily air temperature, and the USWB method requires daily averages of air temperature, relative humidity, wind speed, and solar radiation. Estimates of annual lake evaporation from pan data are frequently within 20 percent of energy-budget method estimates. Results of evaporation estimates from the Hamon method and the USWB method were compared against historical pan data at five selected reservoirs in Texas (Benbrook Lake, Canyon Lake, Granger Lake, Hords Creek Lake, and Sam Rayburn Lake) to evaluate their performance and to develop coefficients to minimize bias for the purpose of estimating reservoir evaporation with accuracies similar to estimates of evaporation obtained from pan data. The modified Hamon method estimates of reservoir evaporation were similar to estimates of reservoir evaporation from pan data for daily, monthly, and annual time periods. The modified Hamon method estimates of annual reservoir evaporation were always within 20 percent of annual reservoir evaporation from pan data. Unmodified and modified USWB method estimates of annual reservoir evaporation were within 20 percent of annual reservoir evaporation from pan data for about 91 percent of the years compared. Average daily differences between modified USWB method estimates and estimates from pan data as a percentage of the average amount of daily evaporation from pan data were within 20 percent for 98 percent of the months. Without any modification to the USWB method, average daily differences as a percentage of the average amount of daily evaporation from pan data were within 20 percent for 73 percent of the months. Use of the unmodified USWB method is appealing because it means estimates of average daily reservoir evaporation can be made from air temperature, relative humidity, wind speed, and solar radiation data collected from remote weather stations without the need to develop site-specific coefficients from historical pan data. Site-specific coefficients would need to be developed for the modified version of the Hamon method.

Harwell, Glenn R.

2012-01-01

65

ARE LARGE, COMETARY-SHAPED PROPLYDS REALLY (FREE-FLOATING) EVAPORATING GAS GLOBULES?  

SciTech Connect

We report the detection of strong and compact molecular line emission (in the CO J = 3-2, 4-3, 6-5, 7-6, {sup 13}CO J = 3-2, HCN, and HCO{sup +} J = 4-3 transitions) from a cometary-shaped object (Carina-frEGG1) in the Carina star-forming region (SFR) previously classified as a photoevaporating protoplanetary disk (proplyd). We derive a molecular mass of 0.35 M{sub Sun} for Carina-frEGG1, which shows that it is not a proplyd, but belongs to a class of free-floating evaporating gas globules (frEGGs) recently found in the Cygnus SFR by Sahai et al. Archival adaptive optics near-IR (Ks) images show a central hourglass-shaped nebula. The derived source luminosity (about 8-18 L{sub Sun }), the hourglass morphology, and the presence of collimated jets seen in Hubble Space Telescope images imply the presence of a jet-driving, young, low-mass star deeply embedded in the dust inside Carina-frEGG1. Our results suggest that the true nature of many or most such cometary-shaped objects seen in massive SFRs and previously labeled as proplyds has been misunderstood, and that these are really frEGGs.

Sahai, R. [Jet Propulsion Laboratory, MS 183-900, California Institute of Technology, Pasadena, CA 91109 (United States); Guesten, R. [Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, D-53121 Bonn (Germany); Morris, M. R., E-mail: raghvendra.sahai@jpl.nasa.gov [Department of Physics and Astronomy, UCLA, Los Angeles, CA 90095-1547 (United States)

2012-12-20

66

Full evaporation dynamic headspace and gas chromatography-mass spectrometry for uniform enrichment of odor compounds in aqueous samples.  

PubMed

A method for analysis of a wide range of odor compounds in aqueous samples at sub-ng mL?¹ to ?g mL?¹ levels was developed by full evaporation dynamic headspace (FEDHS) and gas chromatography-mass spectrometry (GC-MS). Compared to conventional DHS and headspace solid phase microextraction (HS-SPME), FEDHS provides more uniform enrichment over the entire polarity range for odor compounds in aqueous samples. FEDHS at 80°C using 3 L of purge gas allows complete vaporization of 100 ?L of an aqueous sample, and trapping and drying it in an adsorbent packed tube, while providing high recoveries (85-103%) of the 18 model odor compounds (water solubility at 25°C: log0.54-5.65 mg L?¹, vapor pressure at 25°C: 0.011-3.2 mm Hg) and leaving most of the low volatile matrix behind. The FEDHS-GC-MS method showed good linearity (r²>0.9909) and high sensitivity (limit of detection: 0.21-5.2 ng mL?¹) for the model compounds even with the scan mode in the conventional MS. The feasibility and benefit of the method was demonstrated with analyses of key odor compounds including hydrophilic and less volatile characteristics in beverages (whiskey and green tea). In a single malt whiskey sample, phenolic compounds including vanillin could be determined in the range of 0.92-5.1 ?g mL?¹ (RSD<7.4%, n=6). For a Japanese green tea sample, 48 compounds including 19 potent odorants were positively identified from only 100 ?L of sample. Heat-induced artifact formation for potent odorants was also examined and the proposed method does not affect the additional formation of thermally generated compounds. Eighteen compounds including 12 potent odorants (e.g. coumarin, furaneol, indole, maltol, and pyrazine congeners) were determined in the range of 0.21-110 ng mL?¹ (RSD<10%, n=6). PMID:22542289

Ochiai, Nobuo; Sasamoto, Kikuo; Hoffmann, Andreas; Okanoya, Kazunori

2012-04-09

67

Feasibility of TFEL application of Ce-doped CaGa 2S 4 and SrGa 2S 4 films prepared by flash evaporation method  

Microsoft Academic Search

Ce-doped CaGa2S4 and SrGa2S4 thin films were prepared for the first time by the flash evaporation method. The films were characterized before and after annealing in H2S(10%)+Ar gas stream by measuring photoluminescence and absorption spectra, X-ray diffraction and electron probe micro analyses. X-ray diffraction curves and absorption spectra before annealing show amorphous behaviour, whereas the annealing leads to a significant

A. Bayramov; H. Najafov; A. Kato; M. Yamazaki; K. Fujiki; S. Iida

2003-01-01

68

Reliability criteria of experimental results for the method of field evaporation of ions from solutions  

Microsoft Academic Search

The method of field evaporation of ions from solutions (FEIS) using electrospraying for ion emission from electrolyte solutions\\u000a into a vacuum chamber of a mass spectrograph allows obtaining unique information on ion salvation in solutions when solutions\\u000a with low electrolyte concentration are used and recording only ions with the maximum energy. This conclusion was made on the\\u000a basis of considering

G. V. Karpov

2010-01-01

69

A temperature programmed evaporation method for exact determination of the amount of stationary phase in chromatographic column packings  

Microsoft Academic Search

A new temperature programmed evaporation method for determination of amount of stationary phase in chromatographic column packings has been developed. The results obtained by testing the method and its applicability have been discussed.

R. N. Nikolov; N. D. Petsev; A. D. Stefanova

1976-01-01

70

Evaporation-enhanced, dynamically-adaptive air (gas)-cooled heat sink for thermal management of high heat dissipation devices  

Microsoft Academic Search

To address the thermal management challenges associated with high power dissipation devices, we describe a novel hybrid thermal management device, which enables significant enhancement of conventional air-cooled heat sinks using on- demand and spatially controlled droplet\\/jet impingement evaporative cooling. The device architecture modifies an air (gas)-cooled heat sink by adding a multiplexed, planar MEMS (microelectromechanical system)-based droplet ejector array as

Andrei G. Fedorov; J. Mark Meacham

2008-01-01

71

Evaporation-Enhanced, Dynamically Adaptive Air (Gas)Cooled Heat Sink for Thermal Management of High Heat Dissipation Devices  

Microsoft Academic Search

To address the thermal management challenges associated with high power dissipation devices, we describe a novel hybrid thermal management device that enables significant enhancement of conventional air-cooled heat sinks using on-demand and spatially controlled droplet\\/jet impingement evaporative cooling. The device architecture modifies an air (gas)-cooled heat sink by adding a multiplexed, planar microelectromechanical system (MEMS)-based droplet ejector array as a

Andrei G. Fedorov; J. Mark Meacham

2009-01-01

72

Motion of Interacting Gas Bubbles in a Viscous Liquid Including Wall Effects and Evaporation  

Microsoft Academic Search

The motion of single and multiple gas bubbles in an otherwise stationary liquid contained in a closed right vertical cylinder is investigated using a modified volume-of-fluid (VOF) method incorporating surface tension stresses. An isolated bubble was considered in a separate paper [4], where the initial bubble radius was small in comparison with that of the cylinder and watt effects were

Li Chen; Suresh V. Garimella; John A. Reizes; Eddie Leonardi

1997-01-01

73

COMPARISON OF METHODS USED TO ESTIMATE LAKE EVAPORATION FOR A WATER BUDGET OF LAKE SEMINOLE, SOUTHWESTERN GEORGIA AND NORTHWESTERN FLORIDA  

Microsoft Academic Search

Four empirical methods for calculating evaporation were compared with calculations of evapo- ration using the energy budget for Lake Seminole, south- western Georgia and northwestern Florida, for April 2000-September 2001. Methods compared were the Priestly-Taylor, Penman, DeBruin-Keijman, and Papa- dakis equations. Evaporation calculated using the energy budget and empirical methods then were compared with estimates published daily by the Georgia

Melinda S. Mosner; Brent T. Aulenbach

2003-01-01

74

Full evaporation headspace gas chromatography for sensitive determination of high boiling point volatile organic compounds in low boiling matrices.  

PubMed

Determination of volatile organic components (VOC's) is often done by static headspace gas chromatography as this technique is very robust and combines easy sample preparation with good selectivity and low detection limits. This technique is used nowadays in different applications which have in common that they have a dirty matrix which would be problematic in direct injection approaches. Headspace by nature favors the most volatile compounds, avoiding the less volatile to reach the injector and column. As a consequence, determination of a high boiling solvent in a lower boiling matrix becomes challenging. Determination of VOCs like: xylenes, cumene, N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N,N-dimethylacetamide (DMA), N-methyl-2-pyrrolidone (NMP), 1,3-dimethyl-2-imidazolidinone (DMI), benzyl alcohol (BA) and anisole in water or water soluble products are an interesting example of the arising problems. In this work, a headspace variant called full evaporation technique is worked out and validated for the mentioned solvents. Detection limits below 0.1?g/vial are reached with RSD values below 10%. Mean recovery values ranged from 92.5 to 110%. The optimized method was applied to determine residual DMSO in a water based cell culture and DMSO and DMA in tetracycline hydrochloride (a water soluble sample). PMID:24103808

Mana Kialengila, Didi; Wolfs, Kris; Bugalama, John; Van Schepdael, Ann; Adams, Erwin

2013-09-19

75

Standard test method for existent gum in fuels by jet evaporation  

SciTech Connect

This method covers determination of the existent gum in motor gasoline and aircraft fuels at the time of test. Provisions are made for the determination of the unwashed gum content of motor gasoline. Summary of method: a measured quantity of fuel is evaporated under controlled conditions of temperature and flow of air or steam. For aviation gasoline and aircraft turbine fuel, the resulting residue is weighed and reported as milligrams per 100 mL. For motor gasoline, the residue is weighed before and after extracting with n-heptane and the results reported as milligrams per 100 mL.

Not Available

1980-01-01

76

Water retention curves of loamy-sandy soils: Transient evaporation method versus steady-state tension and pressure techniques  

Microsoft Academic Search

Water retention curves of loamy-sandy soils at the agricultural test site Wagna (Austria) were measured using both the simplified evaporation method according to Schindler (Arch. Acker- u. Pflanzenbau u. Bodenkd. Berlin 24, 1-7, 1980) and steady-state tension and pressure techniques. The soil was sampled with 250-ccm and 100-ccm steel pipes for the evaporation method and the steady-state technique, respectively. In

G. Winkler; E. Eberhard; J. Fank; S. Birk

2009-01-01

77

Large scale synthesis of highly pure single crystalline tellurium nanowires by thermal evaporation method.  

PubMed

Single crystalline tellurium nanowires were successfully synthesized in large scale by a facile approach of vaporizing tellurium metal and condensing the vapor in an inert atmosphere onto a Si substrate. Tellurium was evaporated by heating at 300 degrees C at 1 torr and condensed on the Si substrate at 100-150 degrees C, in the downstream of argon (Ar) gas at a flow rate of 25 sccm for 30 min. The as-synthesized nanowires have diameters between 100-300 nm and lengths up to several micrometers. The single crystalline nanowires grew in a preferred [0001] direction. The obtained nanowires were highly pure as only tellurium metal was used in the vaporization process, and no other reagent, surfactant, or template were used for the growth. This low temperature and high-yield approach to the tellurium nanowires synthesis may facilitate its industrial production for various applications. PMID:17252770

Mohanty, Paritosh; Park, Jeunghee; Kim, Bongsoo

2006-11-01

78

Method and apparatus for fuel gas moisturization and heating  

DOEpatents

Fuel gas is saturated with water heated with a heat recovery steam generator heat source. The heat source is preferably a water heating section downstream of the lower pressure evaporator to provide better temperature matching between the hot and cold heat exchange streams in that portion of the heat recovery steam generator. The increased gas mass flow due to the addition of moisture results in increased power output from the gas and steam turbines. Fuel gas saturation is followed by superheating the fuel, preferably with bottom cycle heat sources, resulting in a larger thermal efficiency gain compared to current fuel heating methods. There is a gain in power output compared to no fuel heating, even when heating the fuel to above the LP steam temperature.

Ranasinghe, Jatila (Niskayuna, NY); Smith, Raub Warfield (Ballston Lake, NY)

2002-01-01

79

Encapsulation of azithromycin into polymeric microspheres by reduced pressure-solvent evaporation method.  

PubMed

Azithromycin loaded microspheres with blends of poly-l-lactide and ploy-D,L-lactide-co-glycolide as matrices were prepared by the atmosphere-solvent evaporation (ASE) and reduced pressure-solvent evaporation (RSE) method. Both the X-ray diffraction spectra and DSC thermographs demonstrated that poly-L-lactide existed in a crystalline form in the ASE microspheres, while an amorphous form was present in the RSE formulations. Besides, solvent removal at atmosphere gave microspheres of porous and rough surfaces, but smooth surfaces appeared in the RSE microspheres. The incorporation efficiency as well as the burst release (cumulative release in the first 24h) in the ASE formulations was 39.94 ± 1.18% and 23.96 ± 2.01% respectively, yet the encapsulation efficiency of the microspheres fabricated under 385 mmHg was high up to 57.19 ± 3.81% and the burst release was 4.12 ± 0.15%. The in vitro drug release studies indicated that the ASE microspheres presented a zero-order profile; while the RSE formulations followed first-order kinetics. Other factors including solidification time, temperature, drug to polymer ratio and pH value of the continuous phase could also influence the physicochemical characteristics and release profiles of microspheres. In conclusion, the overall improvement of microspheres in appearance, encapsulation efficiency and controlled drug release through the RSE method could be easily fulfilled under optimal preparation conditions. PMID:22583850

Li, Xiujuan; Chang, Si; Du, Guangsheng; Li, Yi; Gong, Junbo; Yang, Mingshi; Wei, Zhenping

2012-05-11

80

Modeling of Liquid Fuel Injection, Evaporation and Mixing in a Gas Turbine Burner Using Large Eddy Simulations  

Microsoft Academic Search

The interaction of turbulence, temperature fluctuation, liquid fuel transport, mixing and evaporation is studied by using\\u000a Large Eddy Simulations (LES). To assess the accuracy of the different components of the methods we consider first isothermal,\\u000a single phase flow in a straight duct. The results using different numerical methods incorporating dynamic Sub-Grid-Scale (SGS)\\u000a models are compared with DNS and experimental data.

D. Caraeni; C. Bergström; L. Fuchs

2000-01-01

81

Reviving the Bowen Ratio method for Actual Evaporation with Distributed Temperature Sensing  

NASA Astrophysics Data System (ADS)

We have used the technique of distributed temperature sensing (DTS) with a fiber optic cable to determine actual evaporation over land. The results were compared with measurements using a surface layer scintilometer, surface renewal and eddy covariance techniques. Dry and wetted sections of a fiber optic cable were suspended from a six meter high tower in a sugar beet trial in KwaZulu-Natal, South Africa. From the principle of a psychrometer, a near continuous observation of vapor pressure and temperature at 0.20 m intervals of a vertical column of air above the field could be derived. Subsequently it allowed accurate determination of the ratio of sensible and latent heat, i.e. the Bowen ratio over time and in the vertical. Using measurements of the net radiation, soil heat flux and the Bowen ratio sensible heat flux, the actual evaporation could be determined as the residual of the shortened energy balance equation. The advantage of the DTS method over the traditional Bowen ratio method is that one and the same sensor (the fiber optic cable) is used, with sufficient accuracy to discriminate small differences in temperature and vapor pressure respectively, hence giving numerous gradient measurements over the vertical. The traditional Bowen ratio method relies on only a few sensors that require careful calibration to detect the real differences of temperature and vapor pressure. Comparing the improved method with the traditional Bowen Ratio method, shows that the improved method gives more stable and constant results than the standard method. The DTS data were reliable, provided that water blown by strong wind from the wetted cable does not affect the temperature of air at the location of the dry cable. Under these conditions the vertical air temperature was not representative for the air temperature over the fetch of the crop. The experiments were carried out in South Africa, in November 2011 (summer) under varying radiation conditions. In this way it was demonstrated that direct exposure of the fiber optic cable to these high radiative conditions (max incoming short wave radiation = 900 w/m^2) had no noticeable effect on the evaporation results.

Luxemburg, W. M. J.; Euser, T.; Everson, C. S.; Mengistu, M. G.; Clulow, A. D.

2012-04-01

82

Onset of thermal ripples at the interface of an evaporating liquid under a flow of inert gas  

NASA Astrophysics Data System (ADS)

The dynamics of thermal ripples at the interface of a volatile pure liquid (C2H5OH) is studied experimentally and numerically. Liquid evaporates under a flow of inert gas (N2) circulating along the interface. The evaporation rate is varied by regulating both the gas flow rate and the gas pressure. Experiments in microgravity environment allowed to identify a transition to "interfacial turbulence," along which some particular events such as nearly periodic and possible intermittent behaviors. Direct numerical simulations have been performed, and compare qualitatively well with experimental results, offering new insights into the physical mechanisms involved. Small-scale ripples appear to arise from a secondary instability of large-scale convection cells and their motion seems to follow the corresponding large-scale surface flow. The relative role of surface tension and buoyancy in triggering these flows is assessed by comparing experiments and simulations in both microgravity and ground conditions. Qualitative features compare satisfactorily well such as typical speed and orientation of the thermal ripples, as well as spiral flow in the bulk.

Scheid, B.; Margerit, J.; Iorio, C. S.; Joannes, L.; Heraud, M.; Queeckers, P.; Dauby, P. C.; Colinet, P.

2012-05-01

83

Worldwide Evaporation Maps.  

National Technical Information Service (NTIS)

World maps are given showing evaporation for the year and for each separate month. The method used for calculating the evaporation was developed at the Main Geophysical Observatory. The calculations were made for 1460 points located on all continents exce...

L. I. Zubenok

1968-01-01

84

TiO2 Based Nanocrystalline Thin Film Gas Sensors Prepared by Ion-assisted Electron beam Evaporation  

Microsoft Academic Search

In this work, we develop TiO2 based nanocrystalline thin films prepared by ion-assisted e-beam evaporation process. N-type and p-type TiO2 gas-sensing layers have been deposited by doping with various metal oxide materials including WO3, MoO3, and NiOx. Structural and morphological characterization by means of AFM, SEM, and XRD reveal the thin film is nanocrystalline structure with fine grain of 10-30

A. Wisitsoraat; E. Comini; G. Sberveglieri; W. Wlodarski; A. Tuantranont

2007-01-01

85

Determination of clothing evaporative resistance on a sweating thermal manikin in an isothermal condition: heat loss method or mass loss method?  

PubMed

This paper addresses selection between two calculation options, i.e heat loss option and mass loss option, for thermal manikin measurements on clothing evaporative resistance conducted in an isothermal condition (T(manikin) = T(a) = T(r)). Five vocational clothing ensembles with a thermal insulation range of 1.05-2.58 clo were selected and measured on a sweating thermal manikin 'Tore'. The reasons why the isothermal heat loss method generates a higher evaporative resistance than that of the mass loss method were thoroughly investigated. In addition, an indirect approach was applied to determine the amount of evaporative heat energy taken from the environment. It was found that clothing evaporative resistance values by the heat loss option were 11.2-37.1% greater than those based on the mass loss option. The percentage of evaporative heat loss taken from the environment (H(e,env)) for all test scenarios ranged from 10.9 to 23.8%. The real evaporative cooling efficiency ranged from 0.762 to 0.891, respectively. Furthermore, it is evident that the evaporative heat loss difference introduced by those two options was equal to the heat energy taken from the environment. In order to eliminate the combined effects of dry heat transfer, condensation, and heat pipe on clothing evaporative resistance, it is suggested that manikin measurements on the determination of clothing evaporative resistance should be performed in an isothermal condition. Moreover, the mass loss method should be applied to calculate clothing evaporative resistance. The isothermal heat loss method would appear to overestimate heat stress and thus should be corrected before use. PMID:21669906

Wang, Faming; Gao, Chuansi; Kuklane, Kalev; Holmér, Ingvar

2011-06-13

86

A New Method of Measuring Gas Compressibility and Gas Gravity  

Microsoft Academic Search

Practically all metering devices used in the oilfield today require some correction factor for gas gravity and gas compressibility factor (Z factor) in their calculations. An error in either gas gravity or Z factor could potentially make a significant difference in these calculations. The accepted method of calculating the Z factor uses critical property and gas gravity correlations. The proposed

V. B. Pilcher

1986-01-01

87

Evaluation of the Energy Budget Method of determining evaporation at Williams Lake, Minnesota, using alternative instrumentation and study approaches  

NASA Astrophysics Data System (ADS)

Best estimates of evaporation at Williams Lake, north central Minnesota, were determined by the energy budget method using optimum sensors and optimum placement of sensors. These best estimates are compared with estimates derived from using substitute data to determine the effect of using less accurate sensors, simpler methods, or remotely measured data. Calculations were made for approximately biweekly periods during five open water seasons. For most of the data substitutions that affected the Bowen ratio, new values of evaporation differed little from best estimates. The three data substitution methods that caused the largest deviations from the best evaporation estimates were (1) using changes in the daily average surface water temperature as an indicator of the lake heat storage term, (2) using shortwave radiation, air temperature, and atmospheric vapor pressure data from a site 110 km away, and (3) using an analog surface water temperature probe. Recalculations based on these data substitutions resulted in differences from the best estimates as much as 89%, 21%, and 10%, respectively. The data substitution method that provided evaporation values that most closely matched the best estimates was measurement of the lake heat storage term at one location in the lake, rather than at 16 locations. Evaporation values resulting from this substitution method usually were within 2% of the best estimates.

Rosenberry, D. O.; Sturrock, A. M.; Winter, T. C.

1993-08-01

88

Toward the Impact of Fuel Evaporation-Combustion Interaction on Spray Combustion in Gas Turbine Combustion Chambers. Part II: Influence of High Combustion Temperature on Spray Droplet Evaporation  

Microsoft Academic Search

\\u000a While the first part of this work dealt with the question related to the impact of partial vaporization on spray flame properties,\\u000a the second part attempts to answer the question how the evaporation process behaves under turbulent premixed combustion conditions.\\u000a According to the Eulerian-Lagrangian RANS-based spray module designed in Part I the non-equilibrium evaporation model, that\\u000a was proven to capture accurately

Amsini Sadiki; W. Ahmadi; Mouldi Chrigui

89

Changes in optimal distribution of heat exchanger area between the evaporator and suction gas heat exchanger when replacing R22 with R407C  

Microsoft Academic Search

An investigation was made on whether the optimal distribution of heat exchanger area between the evaporator and the suction gas heat exchanger, at a given cost, will change when R22 is replaced with the non-azeotropic mixture R407C. A comprehensive computer program was used to simulate a refrigeration plant, originally designed for R22, where the tube-and-shell evaporator is of dry-expansion type.

Cecilia Gabrielii; Lennart Vamling

1998-01-01

90

Evaluation and generalization of radiation?based methods for calculating evaporation  

Microsoft Academic Search

Abstract: Eight radiation-based equations,for determining,evaporation,were evaluated and expressed in five generalized forms. Five evaporation equations (Abtew, Hargreaves, Makkink, Priestley and Taylor and Turc), where each represents one generalized form, were then compared with pan evaporation measured at Changins station in Switzerland. The comparison was first made using the original constant values involved in each equation, and then using the recalibrated

V. P. Singh

2000-01-01

91

Evaluation of the energy budget method of determining evaporation at Williams Lake, Minnesota, using alternative instrumentation and study approaches  

USGS Publications Warehouse

Best estimates of evaporation were determined by the energy budget method using optimum sensors and optimum placement of sensors. For most of the data substitutions that affected the Bowen ratio, new values of evaporation differed little from best estimates. The three data substitution methods that caused the largest deviations from the best evaporation estimates were (1) using changes in the daily average surface water temperature as an indicator of the lake heat storage term, (2) using shortwave radiation, air temperature, and atmospheric vapor pressure data from a site 110 km away, and (3) using an analog surface water temperature probe. Recalculations based on these data substitutions resulted in differences from the best estimates as much as 89%, 21% and 10%, respectively. The data substitution method that provided evaporation values that most closely matched the best estimates was measurement of the lake heat storage term at one location in the lake, rather than at 16 locations. Evaporation values resulting from this substitution method usually were within 2% of the best estimates. -from Authors

Rosenberry, D. O.; Sturrock, A. M.; Winter, T. C.

1993-01-01

92

Fabrication by Coaxial-Type Vacuum Arc Evaporation Method and Characterization of Bismuth Telluride Thin Films  

NASA Astrophysics Data System (ADS)

We prepared both n- and p-type bismuth telluride thin films by using a coaxial-type vacuum arc evaporation method. The atomic compositions of the as-grown thin films and several annealed thin films were comparable to that of bulk bismuth telluride. Their thermoelectric properties were measured and found to be comparable to those of bulk materials. The Seebeck coefficient and electrical conductivity of the as-grown thin films were improved by the annealing process. The measured figures of merit ( ZT) of the films were 0.86 for the n-type and 0.41 for the p-type at 300 K for annealing temperatures of 573 K and 523 K, respectively.

Uchino, M.; Kato, K.; Hagino, H.; Miyazaki, K.

2013-07-01

93

Optical Properties of CdS Nanobelts and Nanosaws Synthesized by Thermal Evaporation Method  

NASA Astrophysics Data System (ADS)

By a simple one-step H2-assisted thermal evaporation method, high quality CdS nanostructures have been successfully fabricated on Au coated Si substrates in large scale. The as-synthesized CdS nanostructures consisted of sword-like nanobelts and toothed nanosaws with a single-crystal hexagonal wurtzite structure. The deposition temperature played an important role in determining the size and morphology of the CdS nanostructures. A combination of vapor-liquid-solid and vapor-solid growth mechanisms were proposed to interpret the formation of CdS nanostructures. Photoluminescence measurement indicated that the nanobelts and nanosaws have a prominent green emission at about 512 nm, which is the band-to-band emission of CdS. The waveguide characteristics of both types of CdS nanostructures were observed and discussed.

Peng, Zhi-wei; Zou, Bing-suo

2012-04-01

94

Method for hot gas conditioning  

DOEpatents

A method for cracking and shifting a synthesis gas by the steps of providing a catalyst consisting essentially of alumina in a reaction zone; contacting the catalyst with a substantially oxygen free mixture of gases comprising water vapor and hydrocarbons having one or more carbon atoms, at a temperature between about 530.degree. C. (1000.degree. F.) to about 980.degree. C. (1800.degree. F.); and whereby the hydrocarbons are cracked to form hydrogen, carbon monoxide and/or carbon dioxide and the hydrogen content of the mixture increases with a corresponding decrease in carbon monoxide, and carbon formation is substantially eliminated.

Paisley, Mark A. (Upper Arlington, OH)

1996-02-27

95

Enhancement and simplification of EBIS operation by evaporative ion cooling through gas mixing  

Microsoft Academic Search

The stepwise ionization in EBIS sources can be extended beyond th time at which neutralization of the electron beam space charge is reached by trapping ions from the residual gas: We have added minor amounts of argon to the residual gas in the main trap. From this gas mixture ions are formed during the whole containment time and extracted to

R. Becker; M. Kleinod; H. Thomae; E. D. Donets

1993-01-01

96

Soil Evaporation  

Technology Transfer Automated Retrieval System (TEKTRAN)

Soil evaporation can significantly influence energy flux partitioning of partially vegetated surfaces, ultimately affecting plant transpiration. While important, quantification of soil evaporation, separately from canopy transpiration, is challenging. Techniques for measuring soil evaporation exis...

97

Evaluation of the Energy Budget Method of determining evaporation at Williams Lake, Minnesota, using alternative instrumentation and study approaches  

Microsoft Academic Search

Best estimates of evaporation at Williams Lake, north central Minnesota, were determined by the energy budget method using optimum sensors and optimum placement of sensors. These best estimates are compared with estimates derived from using substitute data to determine the effect of using less accurate sensors, simpler methods, or remotely measured data. Calculations were made for approximately biweekly periods during

D. O. Rosenberry; A. M. Sturrock; T. C. Winter

1993-01-01

98

Alternative Methods for the Reduction of Evaporation: Practical Exercises for the Science Classroom  

ERIC Educational Resources Information Center

|Across the world, freshwater is valued as the most critically important natural resource, as it is required to sustain the cycle of life. Evaporation is one of the primary environmental processes that can reduce the amount of quality water available for use in industrial, agricultural and household applications. The effect of evaporation becomes…

Schouten, Peter; Putland, Sam; Lemckert, Charles J.; Parisi, Alfio V.; Downs, Nathan

2012-01-01

99

Synthesis and optical properties of zinc oxide nanoparticles grown on Sn-coated silicon substrate by thermal evaporation method  

NASA Astrophysics Data System (ADS)

The Zinc oxide (ZnO) nanoparticles have been grown on n type silicon substrate using tin (Sn) metal as seed layer by a low cost thermal evaporation method. SEM images show that the ZnO nanoparticles have been uniformely grown on the whole substrate surface relatively perpendicular to the substrate. The Photoluminescence (PL) spectrum consists of strong UV emission at wavelength of 355 nm along with a broad near band edge (NBE) emission covering a wide range of wavelength from 370 to 550 nm. This broadening region exhibits blue, violet and green emission due to the presence of native defects such as zinc interstitial (Zni), oxygen vacancy (VO) and oxygen interstitial (Oi) in the band gap of ZnO. Raman spectroscopy shows the existence of E2 mode at 437 cm-1 which confirms the pure wurtzite hexagonal phase of ZnO. The optical and structural properties of ZnO nanoparticles could be explored for blue-violet light emitting diodes (LEDs) and gas sensing applications.

Somvanshi, Divya; Jit, S.

2013-01-01

100

Consecutive combination of multistep outflow and evaporation method to determine soil hydraulic properties over a wide pressure head range  

NASA Astrophysics Data System (ADS)

Simulation of water flow in unsaturated soils requires accurate knowledge of the soil hydraulic properties. The two standard methods for the simultaneous determination of the water retention and hydraulic conductivity function in the laboratory are the multistep outflow and the evaporation method. The multistep outflow method provides data only in the pressure head range corresponding to relatively moist conditions, whereas the evaporation method has its highest information content in the medium to dry range. A comparison of both methods showed very similar results in the pressure head region where both provide reliable information on the soil hydraulic properties, but distinct differences become evident if results are extrapolated beyond this range. To obtain reliable estimates of soil hydraulic properties in a wider range of soil moisture, we propose to combine both methods in a consecutive manner. The combined experiment we present starts with a multistep outflow experiment which is directly followed by an evaporation experiment. We test this experimental design with both synthetic data and real laboratory experiments. In the evaluation of the combined experiment, data points for the retention and conductivity functions are calculated from the evaporation experiment and included into the objective function for the inverse simulation of the multistep outflow experiment. The combined evaluation leads to a greatly improved estimate of the hydraulic properties in a wide moisture range, circumvents the unreliable extrapolation beyond the different pressure head ranges of the separate experiments and significantly reduces the model error induced by such extrapolations.

Schelle, Henrike; Iden, Sascha C.; Durner, Wolfgang

2010-05-01

101

Evaporation of acoustically levitated multi-component liquid droplets  

Microsoft Academic Search

A theoretical model for the evaporation of multi-component liquid droplets based on the model by Abramzon and Sirignano is presented and applied to the evaporation of acoustically levitated droplets. The liquid phase is treated as a thermodynamically real fluid, using the UNIFAC method for calculating the component activities, and the gas phase as ideal. Computational results, which consist in the

G. Brenn; L. J. Deviprasath; F. Durst; C. Fink

2007-01-01

102

Synthesis and Properties of (1-x)PZN-xBZN Solid-Solution Compounds by Liquid-Evaporation Method  

Microsoft Academic Search

Solid-solution compounds of (1- x)PZN- xBZN were synthesized by a spray-drying method, which is one of the liquid-evaporation methods. The morphology and size of metal nitrate powders could be changed by processing by the spray-drying method. More than 10 mol% BZN was needed to stabilize the 100% perovskite phase with the method. Lattice parameters of perovskite structure increased with the

Sang-goo Kang; Hwan Kim; Koichiro Takahashi; Masayuki Tsukioka

1994-01-01

103

Fabrication and characterization of bismuth–telluride-based alloy thin film thermoelectric generators by flash evaporation method  

Microsoft Academic Search

Bismuth–telluride-based alloy thin film thermoelectric generators are fabricated by a flash evaporation method. We prepare Bi0.4Te3.0Sb1.6 (p-type) and Bi2.0Te2.7Se0.3 (n-type) powders for the fabrication of the flash evaporated thin films. The overall size of the thin film thermoelectric generators, which consist of seven pairs of legs connected by aluminum electrodes, is 20mm by 15mm. Each leg is 15mm long, 1mm

M. Takashiri; T. Shirakawa; K. Miyazaki; H. Tsukamoto

2007-01-01

104

Study of n-ZnO/ p-SiNW heterostructures grown by thermal evaporation method  

NASA Astrophysics Data System (ADS)

Recently SiNW (silicon nanowire) based devices have attracted great attention in the development of novel nanoelectronic devices due to their unique one-dimensional nature and associated electrical and optical properties compared to bulk silicon. In this work, n-type ZnO (Zinc Oxide) nanowire (NW) thin film was grown on p-type SiNW (silicon nanowire) arrays by simple and cost effective thermal evaporation method to obtain an n-ZnONW/ p-SiNW based heterojunction diode without using any seed layer. The SiNW arrays used for the growth of ZnONWs were developed on a p-Si wafer by using the electroless etching method. The large area ohmic contacts at top and bottom of the structure were fabricated by depositing silver and aluminium respectively. The SEM and XRD data demonstrate a good crystalline quality of the ZnONWs grown on the SiNWs. The current-voltage characteristics of the nanowire-based heterostructure device show the non-ideal diode characteristics with a high current rectification ratio of 190 and a low leakage current of 1.86×10-8 A.

Hazra, Purnima; Jit, S.

2013-06-01

105

Improved physicochemical characteristics of artemisinin-nicotinamide solid dispersions by solvent evaporation and freeze dried methods.  

PubMed

Artemisinin (ARMN) is a drug of choice against drug-resistant malaria especially due to Plasmodium falciparum. Being poorly soluble in water, its solid dispersions with nicotinamide (NA) were prepared at various drug-carrier ratios (1:1, 1:4, 1:6, 1:8, 1:10) by solvent evaporation and freeze drying methods. These solid dispersions were characterized by differential scanning calorimetery (DSC), fourier transform infrared spectroscopy (FTIR), X-ray diffraction patterns (XRD), phase solubility and dissolution studies. Artemisinin and nicotinamide both were found completely crystalline as shown by their XRD patterns. Physical mixtures (PMs) showed decreased intensity in their XRD patterns while solid dispersions by solvent evaporation method (SLVPs) exhibited displaced angles and decreased intensity whereas freeze dried solid dispersions (FDSDs) showed least number of peaks having low intensity and maximum displaced angles. DSC thermograms of drug-carrier ratios at 1:1-1:4 showed lower melting temperature than artemisinin and nicotinamide in all preparations. Endothermic temperature of artemisinin in PMs and SLVPs increased with rise of nicotinamide content upto 1:6 ratio followed by decline. All samples showed crystallization temperature below the artemisinin except drug-carrier ratio 1:6 of PMs while ?H value was minimum at this ratio. FDSDs produced lowest endothermic temperature than corresponding PMs and SLVPs. SLVPs exhibited band shifting in both functional and fingerprint region compared to respective PMs as exhibited by their FTIR spectra. FDSDs and SLVPs showed different nature of bonding among artemisinin and nicotinamide. FDSDs produced strongest CONH(2) bonding followed by SLVPs and PMs respectively. PMs produced significantly higher aqueous solubility and rate of dissolution as compared to artemisinin alone. SLVPs exhibited improved solubility and dissolution profile corresponding to PMs. FDSDs showed highest release rate and aqueous solubility followed by SLVPs and PMs at all ratios. PMs and SLVPs showed their highest dissolution profile at 1:6 drug-carrier ratio followed by gradual decrease while FDSDs progressed in dissolution rate with increase of nicotinamide content successively upto maximum at 1:10 ratio. PMID:22459476

Ansari, Muhammad Tayyab; Pervez, Humayun; Shehzad, Muhammad Tariq; Mahmood, Zahid; Razi, Muhammad Tahir; Ranjha, Nazar Muhammad; Khanum, Nuzhat

2012-04-01

106

Prediction of chilling times of foods in situations where evaporative cooling is significant—Part 1. Method development  

Microsoft Academic Search

The finite difference method was used to simulate the unsteady state cooling of spheres, infinite slabs and infinite cylinders of food materials subject to both convection and evaporation at the product surface. Simulations were conducted across wide ranges of air temperature, surface heat transfer coefficient, product initial temperature, surface water activity and air relative humidity. Algebraic equations are proposed for

Sawitri Chuntranuluck; C. M. Wells; A. C. Cleland

1998-01-01

107

Evaluation of the energy budget method of determining evaporation at Williams Lake, Minnesota, using alternative instrumentation and study approaches  

Microsoft Academic Search

Best estimates of evaporation at Williams Lake, north central Minnesota, were determined by the energy budget method using optimum sensors and optimum placement of sensors. These best estimates are compared with estimates derived from using substitute data to determine the effect of approximately biweekly periods using five open water seasons. For most of the data substitutions that affected the Bowen

D. O. Rosenberry; A. M. Sturrock; T. C. Winter

1993-01-01

108

Could CoRoT-7b and Kepler-10b be remnants of evaporated gas or ice giants?  

NASA Astrophysics Data System (ADS)

We present thermal mass loss calculations over evolutionary time scales for the investigation if the smallest transiting rocky exoplanets CoRoT-7b ( ˜1.68REarth) and Kepler-10b ( ˜1.416REarth) could be remnants of an initially more massive hydrogen-rich gas giant or a hot Neptune-class exoplanet. We apply a thermal mass loss formula which yields results that are comparable to hydrodynamic loss models. Our approach considers the effect of the Roche lobe, realistic heating efficiencies and a radius scaling law derived from observations of hot Jupiters. We study the influence of the mean planetary density on the thermal mass loss by placing hypothetical exoplanets with the characteristics of Jupiter, Saturn, Neptune, and Uranus to the orbital location of CoRoT-7b at 0.017 AU and Kepler-10b at 0.01684 AU and assuming that these planets orbit a K- or G-type host star. Our findings indicate that hydrogen-rich gas giants within the mass domain of Saturn or Jupiter cannot thermally lose such an amount of mass that CoRoT-7b and Kepler-10b would result in a rocky residue. Moreover, our calculations show that the present time mass of both rocky exoplanets can be neither a result of evaporation of a hydrogen envelope of a "Hot Neptune" nor a "Hot Uranus"-class object. Depending on the initial density and mass, these planets most likely were always rocky planets which could lose a thin hydrogen envelope, but not cores of thermally evaporated initially much more massive and larger objects.

Leitzinger, M.; Odert, P.; Kulikov, Yu. N.; Lammer, H.; Wuchterl, G.; Penz, T.; Guarcello, M. G.; Micela, G.; Khodachenko, M. L.; Weingrill, J.; Hanslmeier, A.; Biernat, H. K.; Schneider, J.

2011-10-01

109

Could CoRoT-7b and Kepler-10b be remnants of evaporated gas or ice giants?  

PubMed Central

We present thermal mass loss calculations over evolutionary time scales for the investigation if the smallest transiting rocky exoplanets CoRoT-7b (?1.68REarth) and Kepler-10b (?1.416REarth) could be remnants of an initially more massive hydrogen-rich gas giant or a hot Neptune-class exoplanet. We apply a thermal mass loss formula which yields results that are comparable to hydrodynamic loss models. Our approach considers the effect of the Roche lobe, realistic heating efficiencies and a radius scaling law derived from observations of hot Jupiters. We study the influence of the mean planetary density on the thermal mass loss by placing hypothetical exoplanets with the characteristics of Jupiter, Saturn, Neptune, and Uranus to the orbital location of CoRoT-7b at 0.017 AU and Kepler-10b at 0.01684 AU and assuming that these planets orbit a K- or G-type host star. Our findings indicate that hydrogen-rich gas giants within the mass domain of Saturn or Jupiter cannot thermally lose such an amount of mass that CoRoT-7b and Kepler-10b would result in a rocky residue. Moreover, our calculations show that the present time mass of both rocky exoplanets can be neither a result of evaporation of a hydrogen envelope of a “Hot Neptune” nor a “Hot Uranus”-class object. Depending on the initial density and mass, these planets most likely were always rocky planets which could lose a thin hydrogen envelope, but not cores of thermally evaporated initially much more massive and larger objects.

Leitzinger, M.; Odert, P.; Kulikov, Yu.N.; Lammer, H.; Wuchterl, G.; Penz, T.; Guarcello, M.G.; Micela, G.; Khodachenko, M.L.; Weingrill, J.; Hanslmeier, A.; Biernat, H.K.; Schneider, J.

2011-01-01

110

Could CoRoT-7b and Kepler-10b be remnants of evaporated gas or ice giants?  

PubMed

We present thermal mass loss calculations over evolutionary time scales for the investigation if the smallest transiting rocky exoplanets CoRoT-7b (?1.68REarth) and Kepler-10b (?1.416REarth) could be remnants of an initially more massive hydrogen-rich gas giant or a hot Neptune-class exoplanet. We apply a thermal mass loss formula which yields results that are comparable to hydrodynamic loss models. Our approach considers the effect of the Roche lobe, realistic heating efficiencies and a radius scaling law derived from observations of hot Jupiters. We study the influence of the mean planetary density on the thermal mass loss by placing hypothetical exoplanets with the characteristics of Jupiter, Saturn, Neptune, and Uranus to the orbital location of CoRoT-7b at 0.017 AU and Kepler-10b at 0.01684 AU and assuming that these planets orbit a K- or G-type host star. Our findings indicate that hydrogen-rich gas giants within the mass domain of Saturn or Jupiter cannot thermally lose such an amount of mass that CoRoT-7b and Kepler-10b would result in a rocky residue. Moreover, our calculations show that the present time mass of both rocky exoplanets can be neither a result of evaporation of a hydrogen envelope of a "Hot Neptune" nor a "Hot Uranus"-class object. Depending on the initial density and mass, these planets most likely were always rocky planets which could lose a thin hydrogen envelope, but not cores of thermally evaporated initially much more massive and larger objects. PMID:21969736

Leitzinger, M; Odert, P; Kulikov, Yu N; Lammer, H; Wuchterl, G; Penz, T; Guarcello, M G; Micela, G; Khodachenko, M L; Weingrill, J; Hanslmeier, A; Biernat, H K; Schneider, J

2011-10-01

111

Decreasing microfluidic evaporation loss using the HMDL method: open systems for nucleic acid amplification and analysis  

Microsoft Academic Search

Evaporation is of great importance when dealing with microfluidic devices with open air\\/liquid interfaces due to the large\\u000a surface-to-volume ratio. For devices utilizing a thermal reaction (TR) reservoir to perform a series of biological and chemical\\u000a reactions, excessive heat-induced microfluidic evaporation can quickly lead to reaction reservoir dry out and failure of the\\u000a overall device. In this study, we present

Chunsun Zhang; Da Xing

2010-01-01

112

A Study for Health Hazard Evaluation of Methylene Chloride Evaporated from the Tear Gas Mixture  

PubMed Central

This study explored the health hazard of those exposed to methylene chloride by assessing its atmospheric concentration when a tear gas mixture was aerially dispersed. The concentration of methylene chloride ranged from 311.1-980.3 ppm (geometric mean, 555.8 ppm), 30 seconds after the dispersion started. However, the concentration fell rapidly to below 10 ppm after dispersion was completed. The concentration during the dispersion did not surpass the National Institute for Occupational Safety and Health 'immediately dangerous to life or health' value of 2,300 ppm, but did exceed the American Conference of Governmental Industrial Hygienists excursion limit of 250 ppm. Since methylene chloride is highly volatile (vapor pressure, 349 mmHg at 20?), the postdispersion atmospheric concentration can rise instantaneously. Moreover, the o-chlorobenzylidenemalononitrile formulation of tear gas (CS gas) is an acute upper respiratory tract irritant. Therefore, tear gas mixtures should be handled with delicate care.

Chung, Eun-Kyo; Yi, Gwang-Yong; Chung, Kwang-Jae; Shin, Jung-Ah; Lee, In-Seop

2010-01-01

113

Assessment of Evaporative Cooling Enhancement Methods for Air-Cooled Geothermal Power Plants: Preprint  

SciTech Connect

Many binary-cycle geothermal power plants are air cooled because insufficient water is available to provide year-round water cooling. The performance of air-cooled geothermal plants is highly dependent on the dry bulb temperature of the air (much more so than fossil fuel plants that operate at higher boiler temperatures), and plant electric output can drop by 50% or more on hot summer days, compared to winter performance. This problem of reduced summer performance is exacerbated by the fact that electricity has a higher value in the summer. This paper describes a spreadsheet model that was developed to assess the cost and performance of four methods for using supplemental evaporative cooling to boost summer performance: (1) pre-cooling with spray nozzles, (2) pre-cooling with Munters media, (3) a hybrid combination of nozzles and Munters media, and (4) direct deluge cooling of the air-cooled condenser tubes. Although all four options show significant benefit, deluge cooling has the potential to be the most economic. However, issues of scaling and corrosion would need to be addressed.

Kutscher, C.; Costenaro, D.

2002-08-01

114

Analysis of sweat evaporation from clothing materials by the ventilated sweat capsule method.  

PubMed

The local influence of three clothing materials i.e. silk, cotton and nylon, in (1) full or (2) partial skin contact or (3) at 3 mm from the skin, on sweat evaporation from the chest skin surface of human subjects was studied. The hygrometer-ventilated capsule method was used and sweating was induced at ambient thermoneutrality by a central heat load following lower-leg immersion in water at 43 degrees C. The presence of clothing delayed the rise in capsule relative humidity (CRH) induced by heat loading. During the first 6 min of heating, CRH rose more steeply with clothing that was in full skin contact than with clothing that had partial or no contact. The rate of decrease in CRH from 1 min to 6 min after heating was not influenced by the presence of clothing or by the different degrees of skin contact. The subsequent return of CRH to the pre-heating level was delayed most by cotton, less by silk and least by nylon. For silk and nylon, partial contact with the skin prolonged the return to control conditions, as compared with full skin contact. PMID:9243163

Otomasu, K; Yamauchi, M; Ohwatari, N; Matsumoto, T; Tsuchiya, K; Kosaka, M

1997-01-01

115

Physical properties of Sb-doped CdSe thin films by thermal evaporation method  

NASA Astrophysics Data System (ADS)

Cadmium selenide (CdSe) thin films were deposited on the glass substrates by using the resistive thermal evaporation method in the vacuum chamber. The effect of antimony doping on the physical properties of CdSe thin film has been investigated. The structural and surface properties such as lattice parameters, grain size, microstrain and dislocation density of the thin films were characterized by X-ray diffraction (XRD) technique. The compositional properties were studied by the mean of Rutherford backscattering (RBS) and UV-Vis-NIR spectrophotometer used to determine the refractive index, absorption coefficient and optical energy band gap of thin films. The FTIR absorption spectra confirmed the presence of CdSe vibrational mode in the range 400 cm-1 to 700 cm-1. The electrical conductivity of the films was carried out with the help of impedance analyzer, which has been increased up to 1% on Sb doping. The transmission has been reduced up to 18% with the increase in Sb doping and shifted toward lower wavelengths

Ali, Mazhar; Syed, Waqar A. A.; Zubair, M.; Shah, Nazar A.; Mehmood, Arshad

2013-11-01

116

Dilute hydrogen sulfide sensing properties of CuO–SnO 2 thin film prepared by low-pressure evaporation method  

Microsoft Academic Search

A low pressure evaporation method was adopted for preparing SnO2 and CuO–SnO2 thin films. Metallic tin and copper were evaporated on the alumina substrate under a low pressure (1 torr) of air atmosphere. As observed with AFM, these evaporated films had unique microstructure in which discrete clusters of SnO2 grains (30 nm) contacted to each other two-dimensionally with large mesopores

Jun Tamaki; Kengo Shimanoe; Yoshihiro Yamada; Yoshifumi Yamamoto; Norio Miura; Noboru Yamazoe

1998-01-01

117

Method for liquefaction of natural gas  

US Patent & Trademark Office Database

A method of altering the heating value of a liquefied natural gas by adding higher heating value components is disclosed. A portion of the liquefied natural gas is used to cool the higher heating value component stream prior to combining the higher heating value components with the liquefied natural gas to obtain a combined stream having a heating value greater than the liquefied natural gas.

Coyle; David A. (Houston, TX)

2013-02-26

118

Kinetic multi-layer model of gas-particle interactions in aerosols and clouds (KM-GAP): linking condensation, evaporation and chemical reactions of organics, oxidants and water  

NASA Astrophysics Data System (ADS)

We present a novel kinetic multi-layer model for gas-particle interactions in aerosols and clouds (KM-GAP) that treats explicitly all steps of mass transport and chemical reaction of semi-volatile species partitioning between gas phase, particle surface and particle bulk. KM-GAP is based on the PRA model framework (Pöschl-Rudich-Ammann, 2007), and it includes gas phase diffusion, reversible adsorption, surface reactions, bulk diffusion and reaction, as well as condensation, evaporation and heat transfer. The size change of atmospheric particles and the temporal evolution and spatial profile of the concentration of individual chemical species can be modeled along with gas uptake and accommodation coefficients. Depending on the complexity of the investigated system and the computational constraints, unlimited numbers of semi-volatile species, chemical reactions, and physical processes can be treated, and the model shall help to bridge gaps in the understanding and quantification of multiphase chemistry and microphysics in atmospheric aerosols and clouds. In this study we demonstrate how KM-GAP can be used to analyze, interpret and design experimental investigations of changes in particle size and chemical composition in response to condensation, evaporation, and chemical reaction. For the condensational growth of water droplets, our kinetic model results provide a direct link between laboratory observations and molecular dynamic simulations, confirming that the accommodation coefficient of water at ~270 K is close to unity (Winkler et al., 2006). Literature data on the evaporation of dioctyl phthalate as a function of particle size and time can be reproduced, and the model results suggest that changes in the experimental conditions like aerosol particle concentration and chamber geometry may influence the evaporation kinetics and can be optimized for efficient probing of specific physical effects and parameters. With regard to oxidative aging of organic aerosol particles, we illustrate how the formation and evaporation of volatile reaction products like nonanal can cause a decrease in the size of oleic acid particles exposed to ozone.

Shiraiwa, M.; Pfrang, C.; Koop, T.; Pöschl, U.

2012-03-01

119

Kinetic multi-layer model of gas-particle interactions in aerosols and clouds (KM-GAP): linking condensation, evaporation and chemical reactions of organics, oxidants and water  

NASA Astrophysics Data System (ADS)

We present a novel kinetic multi-layer model for gas-particle interactions in aerosols and clouds (KM-GAP) that treats explicitly all steps of mass transport and chemical reaction of semi-volatile species partitioning between gas phase, particle surface and particle bulk. KM-GAP is based on the PRA model framework (Pöschl-Rudich-Ammann, 2007), and it includes gas phase diffusion, reversible adsorption, surface reactions, bulk diffusion and reaction, as well as condensation, evaporation and heat transfer. The size change of atmospheric particles and the temporal evolution and spatial profile of the concentration of individual chemical species can be modeled along with gas uptake and accommodation coefficients. Depending on the complexity of the investigated system, unlimited numbers of semi-volatile species, chemical reactions, and physical processes can be treated, and the model shall help to bridge gaps in the understanding and quantification of multiphase chemistry and microphysics in atmospheric aerosols and clouds. In this study we demonstrate how KM-GAP can be used to analyze, interpret and design experimental investigations of changes in particle size and chemical composition in response to condensation, evaporation, and chemical reaction. For the condensational growth of water droplets, our kinetic model results provide a direct link between laboratory observations and molecular dynamic simulations, confirming that the accommodation coefficient of water at ~270 K is close to unity. Literature data on the evaporation of dioctyl phthalate as a function of particle size and time can be reproduced, and the model results suggest that changes in the experimental conditions like aerosol particle concentration and chamber geometry may influence the evaporation kinetics and can be optimized for efficient probing of specific physical effects and parameters. With regard to oxidative aging of organic aerosol particles, we illustrate how the formation and evaporation of volatile reaction products like nonanal can cause a decrease in the size of oleic acid particles exposed to ozone.

Shiraiwa, M.; Pfrang, C.; Koop, T.; Pöschl, U.

2011-12-01

120

Exploring Evaporation  

NSDL National Science Digital Library

Students learn what evaporation is and how various factors--time, heat, surface area, and wind--affect it. They also discover that water does not always evaporate at the same rate and saltwater leaves something behind when it evaporates. Finally, students a

Eichinger, John

2009-05-15

121

The temperature variance method: a powerful tool in the estimation of actual evaporation rates  

Microsoft Academic Search

The usefulness of the temperature variance technique for the estimation of actual evaporation rates under humid tropical conditions was tested with a set of micrometerolo gical data collected above a 6- year-old pine plantation in Viti Levu, Fiji. Values for the sensible and latent heat fluxes obtained from the standard deviations of fast responding dry and wet bulb thermocouples during

H. F. VUGTS; M. J. WATERLOO; F. J. BEEKMAN; K. F. A. FRUMAU; L. A. BRUUNZEEL

1993-01-01

122

Direct measurement of the latent heat of evaporation by flowmetric method  

Microsoft Academic Search

This paper describes an original and very simple device dedicated to measure the latent heat of evaporation of various liquids at ambient temperature. This apparatus is composed of two very thin heat flow sensors glued to a heat sink. One of these sensors is covered with oiled textile, and the other one with an identical dry textile intended to receive

Pascale Godts; Daniel Dupont; Didier Leclercq

2005-01-01

123

Time-dependent Marangoni-Bénard instability of an evaporating binary-liquid layer including gas transients  

NASA Astrophysics Data System (ADS)

We are here concerned with Bénard instabilities in a horizontal layer of a binary liquid, considering as a working example the case of an aqueous solution of ethanol with a mass fraction of 0.1. Both the solvent and the solute evaporate into air (the latter being insoluble in the liquid). The system is externally constrained by imposing fixed ``ambient'' pressure, humidity, and temperature values at a certain effective transfer distance above the liquid-gas interface, while the ambient temperature is also imposed at the impermeable rigid bottom of the liquid layer. Fully transient and horizontally homogeneous solutions for the reference state, resulting from an instantaneous exposure of the liquid layer to ambient air, are first calculated. Then, the linear stability of these solutions is studied using the frozen-time approach, leading to critical (monotonic marginal stability) curves in the parameter plane spanned by the liquid layer thickness and the elapsed time after initial contact. This is achieved for different ratios of the liquid and gas thicknesses, and in particular yields critical times after which instability sets in (for given thicknesses of both phases). Conversely, the analysis also predicts a critical thickness of the liquid layer below which no instability ever occurs. The nature of such critical thickness is explained in detail in terms of mass fraction profiles in both phases, as it indeed appears that the most important mechanism for instability onset is the solutal Marangoni one. Importantly, as compared to the result obtained previously under the quasi-steady assumption in the gas phase [H. Machrafi, A. Rednikov, P. Colinet, and P. C. Dauby, Eur. Phys. J. Spec. Top. 192, 71 (2011)], it is shown that relaxing this assumption may yield essentially lower values of the critical liquid thickness, especially for large gas-to-liquid thickness ratios. A good-working analytical model is developed for the description of such delicate transient effects in the gas. The analysis reveals that the system considered in this paper is generally highly unstable, the instability setting in even for very small times and liquid thicknesses.

Machrafi, H.; Rednikov, A.; Colinet, P.; Dauby, P. C.

2013-08-01

124

Development of a novel liquid chromatography — Evaporative light scattering detection method for bacitracins and applications to quality control of pharmaceuticals  

Microsoft Academic Search

A novel liquid chromatography method for the direct determination of bacitracin main components (Bc-A, -B1, -B2 and -B3), a basic, cyclic polypeptide antibiotic, was developed and validated, based on ion pairs formation with trifluoroacetic acid (TFA) and evaporative light scattering detection (ELSD).The selected analytical column was the Waters Nova-pak C8 (3.9×150mm), for which the optimum (using modified Simplex algorithm) mobile

Artemis K. Sarri; Nikolaos C. Megoulas; Michael A. Koupparis

2006-01-01

125

Adsorption behaviors of organic vapors using mesoporous silica particles made by evaporation induced self-assembly method  

Microsoft Academic Search

Spherical mesoporous silica materials with controllable surface area and uniform pore size were synthesized via evaporation induced self-assembly (EISA) method in this study. Both well-ordered and less-ordered mesoporous silica particle (MSP) adsorbents were made via adjusting the surfactant\\/silica precursor molar ratio. And the relationships between the physical characteristics of MSP adsorbents and the acetone adsorption behaviors were examined for the

Chin-Te Hung; Hsunling Bai

2008-01-01

126

Instrumentation for measuring lake and reservoir evaporation by the energy-budget and mass-transfer methods  

USGS Publications Warehouse

Instrumentation currently used by the U.S. Geological Survey in studies of lake and reservoir evaporation is described in this paper. This instrumentation is used for the measurement of solar and terrestrial energy necessary to apply the mass-transfer or energy budget methods. The energy budget requires a quantative determination of all form of energy entering or leaving the lake as well as determination of the change in storage of energy within the lake. (USGS)

Sturrock, A. M., Jr.

1985-01-01

127

Nanostructured SnO(2) films prepared from evaporated Sn and their application as gas sensors.  

PubMed

This paper describes the morphology, stoichiometry, microstructure and gas sensing properties of nanoclustered SnO(x) thin films prepared by Sn evaporation followed by a rheotaxial growth and thermal oxidation process. Electron microscopy was used to investigate, in detail, the evolution of the films as the oxidation temperature was increased. The results showed that the contact angle, perpendicular height, volume and microstructure of the clusters all changed significantly as a result of the thermal oxidation processes. Electron diffraction and x-ray photoelectron spectroscopy measurements revealed that after oxidation at a temperature of 600?°C, the Sn clusters were fully transformed into porous three-dimensional polycrystalline SnO(2) clusters. On the basis of these results, a prototype SnO(2) sensor was fabricated and sensing measurements were performed with H(2) and NO(2) gases. At operating temperatures of 150-200?°C the film produced measurable responses to concentrations of H(2) as low as 600 ppm and NO(2) as low as 500 ppb. PMID:21817731

Partridge, J G; Field, M R; Peng, J L; Sadek, A Z; Kalantar-Zadeh, K; Du Plessis, J; McCulloch, D G

2008-02-20

128

Dependence of evaporation on meteorological variables at different time-scales and intercomparison of estimation methods  

Microsoft Academic Search

This paper consists of two parts. In the first part, the significance of five major factors, including solar radiation, vapour pressure deficit, relative humidity, wind speed and air temperature, that control evaporation were evaluated comparatively at different time-scales using the data from Changines station in Switzerland. The comparative evaluation was made at hourly, daily, 10-day and monthly time-scales. It was

C.-Y. Xu; V. P. Singh

1998-01-01

129

Method for detecting gas turbine engine flashback  

SciTech Connect

A method for monitoring and controlling a gas turbine, comprises predicting frequencies of combustion dynamics in a combustor using operating conditions of a gas turbine, receiving a signal from a sensor that is indicative of combustion dynamics in the combustor, and detecting a flashback if a frequency of the received signal does not correspond to the predicted frequencies.

Singh, Kapil Kumar; Varatharajan, Balachandar; Kraemer, Gilbert Otto; Yilmaz, Ertan; Lacy, Benjamin Paul

2012-09-04

130

Canadian Shield brine from the Con Mine, Yellowknife, NT, Canada: Noble gas evidence for an evaporated Palaeozoic seawater origin mixed with glacial meltwater and Holocene recharge  

Microsoft Academic Search

Dissolved noble gas concentrations were measured in high salinity (270g\\/L) Ca(Na)-Cl groundwaters from the Con Mine, Yellowknife, Canada in an effort to discriminate between two possible origins, as either a brine generated by evaporative enrichment in a Paleozoic inland sea, or marine water concentrated by freezing during glacial times. Major ion and isotope geochemistry indicate that brines from the deepest

Shane Greene; Nick Battye; Ian Clark; Tom Kotzer; Dennis Bottomley

2008-01-01

131

Gas chromatography–mass spectrometry analysis of volatile compounds from Houttuynia cordata Thunb after extraction by solid-phase microextraction, flash evaporation and steam distillation  

Microsoft Academic Search

Various sampling techniques including flash evaporation (FE), headspace solid-phase microextraction (HS-SPME) and steam distillation (SD) were compared for the gas chromatography–mass spectrometry of volatile constituents present in Houttuynia cordata Thunb (HCT). 2-Undecanone (22.21%) and houttuynum (7.23%) were predominant components of HCT samples obtained by HS-SPME whereas those levels were 3.95 and 3.60% in the same samples by FE and 25.93

Minmin Liang; Meiling Qi; Changbin Zhang; Shan Zhou; Ruonong Fu; Junxiong Huang

2005-01-01

132

Witnessing Evaporation  

NSDL National Science Digital Library

The engineers at Splash Engineering (the students) have been commissioned by Thirsty County to conduct a study of evaporation and transpiration in their region. During one week, students observe and measure (by weight) the ongoing evaporation of water in pans set up with different variables, and then assess what factors may affect evaporation. Variables include adding to the water an amount of soil and an amount of soil with growing plants.

Integrated Teaching And Learning Program

133

Effects of heating method and conditions on the evaporation rate and quality attributes of black mulberry ( Morus nigra ) juice concentrate  

Microsoft Academic Search

Black mulberry juice was concentrated by different heating methods, including conventional heating and microwave heating,\\u000a at different operational pressures (7.3, 38.5 and 100 kPa). The effects of each method on evaporation rate, quality attributes\\u000a of concentrated juice were investigated. The final juice concentration of 42° Brix was achieved in 140, 120, and 95 min at\\u000a 100, 38.5, and 7.3 kPa respectively by using

Mahboubeh Fazaeli; Ghazale Hojjatpanah; Zahra Emam-Djomeh

134

Evaporating apparatus  

SciTech Connect

A heat recovery system is described comprising in combination forming a closed loop, an evaporator means for converting a working fluid into vapor with a waste heat, a steam engine means for driving a load with the vapor produced in the evaporator means, a condensor means for liquefying the vapor coming out of the steam engine means, and a pump means for circulating the working fluid in the closed loop, the improvement of the evaporator means comprising a high temperature side evaporator and a low temperature side evaporator connected in series in a flowing direction of a heat source, a first and second pipe line for directing fluid being evaporated therethrough, and an ejector having a suction inlet and a discharge outlet of drive steam and an induction port of steam being sucked, wherein the first pipe is linked through the high temperature side evaporator to the suction inlet of the ejector, and the second pipe line is branched from the first pipe line at the upstream side of the high temperature side evaporator, and linked through the low temperature side evaporator to the induction port of the ejector.

Sumitomo, H.

1988-06-28

135

Gas Chromatographic Methods for Liquid Propellant Analysis.  

National Technical Information Service (NTIS)

This report outlines the results of a study to consider the application of gas chromatographic methods for analysis to the three propellant systems, 50:50 unsymmetrical dimethyl hydrazine-hydrazine, chlorine trifluoride, and nitrogen tetroxide. Polyethyle...

R. A. Hagstrom W. Glowa W. T. Neville W. A. Nichols

1966-01-01

136

Post-column addition as a method of controlling triacylglycerol response coefficient of an evaporative light scattering detector in liquid chromatography–evaporative light-scattering detection  

Microsoft Academic Search

The non-linear response is generally the main limitation to the general quantitative use of evaporative light-scattering detection (ELSD). In the particular case of triacylglycerol (TG) analysis, we present a preliminary paper dealing with the use of post-column additives as a means of monitoring the response of such a detector. As TG can form molecular association complexes (ligand–ligate associations) with either

Sylvie Héron; Michel Dreux; Alain Tchapla

2004-01-01

137

Experimental Determination of Liquid Evaporation Rates in Superheated Fluidized Beds  

Microsoft Academic Search

Important applications of fast fluidized beds include reactors where liquid feed is sprayed into the co-current flow of solid particles and gas. When the gas and the solid particles are superheated relative to the saturation temperature of the liquid, the liquid drops evaporate at a rate governed by interfacial heat and mass transfer. This article describes an experimental method to

W. K. Gu; John C. Chen

1997-01-01

138

Atomically thin layers of MoS2via a two step thermal evaporation-exfoliation method  

NASA Astrophysics Data System (ADS)

Two dimensional molybdenum disulfide (MoS2) has recently become of interest to semiconductor and optic industries. However, the current methods for its synthesis require harsh environments that are not compatible with standard fabrication processes. We report on a facile synthesis method of layered MoS2 using a thermal evaporation technique, which requires modest conditions. In this process, a mixture of MoS2 and molybdenum dioxide (MoO2) is produced by evaporating sulfur powder and molybdenum trioxide (MoO3) nano-particles simultaneously. Further annealing in a sulfur-rich environment transforms majority of the excess MoO2 into layered MoS2. The deposited MoS2 is then mechanically exfoliated into minimum resolvable atomically thin layers, which are characterized using micro-Raman spectroscopy and atomic force microscopy. Furthermore Raman spectroscopy is employed to determine the effect of electrochemical lithium ion exposure on atomically thin layers of MoS2.Two dimensional molybdenum disulfide (MoS2) has recently become of interest to semiconductor and optic industries. However, the current methods for its synthesis require harsh environments that are not compatible with standard fabrication processes. We report on a facile synthesis method of layered MoS2 using a thermal evaporation technique, which requires modest conditions. In this process, a mixture of MoS2 and molybdenum dioxide (MoO2) is produced by evaporating sulfur powder and molybdenum trioxide (MoO3) nano-particles simultaneously. Further annealing in a sulfur-rich environment transforms majority of the excess MoO2 into layered MoS2. The deposited MoS2 is then mechanically exfoliated into minimum resolvable atomically thin layers, which are characterized using micro-Raman spectroscopy and atomic force microscopy. Furthermore Raman spectroscopy is employed to determine the effect of electrochemical lithium ion exposure on atomically thin layers of MoS2. Electronic supplementary information (ESI) available: Further AFM scans and a discussion on the reaction mechanisms are included. See DOI: 10.1039/c1nr10803d

Balendhran, Sivacarendran; Ou, Jian Zhen; Bhaskaran, Madhu; Sriram, Sharath; Ippolito, Samuel; Vasic, Zoran; Kats, Eugene; Bhargava, Suresh; Zhuiykov, Serge; Kalantar-Zadeh, Kourosh

2012-01-01

139

Dielectric behaviour of BaTiO3 \\/ P (VDF-HFP) composite thin films prepared by solvent evaporation method  

Microsoft Academic Search

This work deals with the study of the molecular mobility as well as the evolution of the permittivity in P(VDF-HFP)\\/BaTiO3 composites. The composite thin films of P(VDF-HFP) with BaTiO3 (0%, 3.5% and 7.2% by v\\/v%) were prepared by solvent evaporation method. In addition a sample of 11.8% in volume fraction of X7R “temperature stable” formulations was prepared in order to

M. Aldas; G. Boiteux; G. Seytre; Z. Ghallabi

2010-01-01

140

Evaporative estimation using data fusion  

Microsoft Academic Search

This paper present evaporative estimation of water using data fusion technique. There are many factors in evaporative locating process that provided for consideration together. So this paper will be study about factors with concerning in meteorology that influential to evaporation and explained about relation of these factors by statistical method. The used data obtained from Thai Meteorological Department which collects

P. Roengruen; V. Tipsuwannaporn; A. Numsomran; Sh. Harnnarong

2008-01-01

141

Utility of Penman-Monteith, Priestley-Taylor, reference evapotranspiration, and pan evaporation methods to estimate pasture evapotranspiration  

USGS Publications Warehouse

Actual evapotranspiration (ETa) was measured at 30-min resolution over a 19-month period (September 28, 2000-April 23, 2002) from a nonirrigated pasture site in Florida, USA, using eddy correlation methods. The relative magnitude of measured ETa (about 66% of long-term annual precipitation at the study site) indicates the importance of accurate ET a estimates for water resources planning. The time and cost associated with direct measurements of ETa and the rarity of historical measurements of ETa make the use of methods relying on more easily obtainable data desirable. Several such methods (Penman-Monteith (PM), modified Priestley-Taylor (PT), reference evapotranspiration (ET 0), and pan evaporation (Ep)) were related to measured ETa using regression methods to estimate PM bulk surface conductance, PT ??, ET0 vegetation coefficient, and Ep pan coefficient. The PT method, where the PT ?? is a function of green-leaf area index (LAI) and solar radiation, provided the best relation with ET a (standard error (SE) for daily ETa of 0.11 mm). The PM method, in which the bulk surface conductance was a function of net radiation and vapor-pressure deficit, was slightly less effective (SE=0.15 mm) than the PT method. Vegetation coefficients for the ET0 method (SE=0.29 mm) were found to be a simple function of LAI. Pan coefficients for the Ep method (SE=0.40 mm) were found to be a function of LAI and Ep. Historical or future meteorological, LAI, and pan evaporation data from the study site could be used, along with the relations developed within this study, to provide estimates of ETa in the absence of direct measurements of ETa. Additionally, relations among PM, PT, and ET0 methods and ETa can provide estimates of ETa in other, environmentally similar, pasture settings for which meteorological and LAI data can be obtained or estimated. ?? 2004 Elsevier B.V. All rights reserved.

Sumner, D. M.; Jacobs, J. M.

2005-01-01

142

Gas turbine combustor operating method  

SciTech Connect

A method is described of operating a combustor comprising the steps of: (a) flowing pressurized air from a source thereof into a liner portion of the combustor through an inlet opening formed in the liner portion; (b) utilizing a first portion of the pressurized air entering the liner portion to cool an interior surface portion of the liner portion; (c) utilizing a second portion of the pressurized air entering the liner portion as combustion air within the liner portion; (d) mixing the combustion air with fuel and burning the fuel-air mixture within the liner portion; and (e) simultaneously controlling the cooling of the interior surface portion and the richness of the fuel-air mixture by selectively varying the air inflow through the inlet opening, the step (a) being performed by flowing pressurized air into an upstream end portion of the liner portion, and the method comprising the further steps of forming in the liner portion an additional air inlet opening spaced in a downstream direction from the first-mentioned inlet opening for receiving pressurized air from a source thereof, and varying the air inflow through the additional inlet opening in generally inverse proportion to the air inflow variance through the first-mentioned inlet opening.

Mongia, H.C.; Coleman, E.B.; Bruce, T.W.

1986-06-17

143

Evaporative Light Scattering Detection Based HPLC Method for the Determination of Polysorbate 80 in Therapeutic Protein Formulations  

PubMed Central

An evaporative light scattering detection (ELSD) based high-performance liquid chromatography (HPLC) method is developed for the determination of polysorbate 80 (tween 80) in therapeutic protein formulations. The method is simple and overcomes the difficulties associated with specificity and sensitivity. The method is suitable for the quantitation of polysorbate 80 in the usual formulation range (0.01–0.1%) as well as in trace amounts ?13 µg/mL. The analysis is based on the removal of protein first by solid-phase extraction using Oasis HLB cartridges followed by HPLC analysis using Inertsil ODS-3 C 18 column (4.6×150 mm, 5 µm) using reversed-phase conditions. The detector response changes exponentially with an increase in polysorbate concentration. A very good linear fit of log ELSD response against log polysorbate 80 concentration is observed. The specificity, sensitivity, precision, and accuracy of the method are suitable for the quantitation of polysorbate 80 in protein formulations.

Nayak, Vikram S.; Tan, Zhijun; Ihnat, Peter M.; Russell, Reb J.; Grace, Michael J.

2012-01-01

144

RPC gas recovery by open loop method  

NASA Astrophysics Data System (ADS)

RPC detectors require to be flushed with small but continuous flow of gas mixture. Dealing with large number of detectors, gas consumption to very large volumes. Gas flow is a running expense and constituent gases are too expensive to be treated as consumables. Exhaust gas mixture from detectors is a potential environmental hazard if discharged directly into the atmosphere. Storage of gases on a large scale also leads to inventory- and safety-related problems. A solution to these problems is the recovery and reuse of exhaust gas mixture from RPC detectors. Close loop method employs recirculation of exhausted gas mixture after purification, analysis and addition of top-up quantities. In open loop method, under consideration here, individual component gases are separated from gas mixture and reused as source. During open loop process, gases liquefiable at low pressures are separated from ones liquefiable at high pressure. The gas phase components within each group are successively separated by either fractional condensation or gravity separation. Gas mixture coming from RPC exhaust is first desiccated by passage through molecular sieve adsorbent type (3A+4A). Subsequent scrubbing over basic activated alumina removes toxic and acidic contaminants such as S2F10 produced during corona (arcing) discharge. In the first stage of separation isobutane and freon are concentrated by diffusion and liquefied by fractional condensation by cooling upto -30 °C. Liquefied gases are returned to source tanks. In the second stage of separation, argon and sulphur hexafluoride, the residual gases, are concentrated by settling due to density difference. SF6 is stored for recovery by condensation at high pressure while argon is further purified by thermal cracking of crossover impurities at 1000 °C followed by wet scrubbing.

Joshi, Avinash; Kalmani, S. D.; Mondal, N. K.; Satyanarayana, B.

2009-05-01

145

Effect of variables in inert gas condensation processing on nanoparticle trajectory simulated by finite volume method.  

PubMed

The finite volume method was applied to the determination of the three-dimensional convection current during inert gas condensation (IGC) processing by using the commercially available software, "Fluent". The lower velocity of the convection current at higher evaporation temperature resulted from the lower value of the coefficient of thermal expansion. The velocity of the convection current increased with increasing chamber pressure, because the driving force of the buoyancy was directly proportional to the gas density. 13% and 17.3% of the particles were trapped during the first period of circulation in the case of the single and double heaters, respectively. PMID:17252783

Lee, Kwang-Min; Juhng, Woo-Nam; Choi, Bo-Young

2006-11-01

146

Atomically thin layers of MoS2 via a two step thermal evaporation-exfoliation method.  

PubMed

Two dimensional molybdenum disulfide (MoS(2)) has recently become of interest to semiconductor and optic industries. However, the current methods for its synthesis require harsh environments that are not compatible with standard fabrication processes. We report on a facile synthesis method of layered MoS(2) using a thermal evaporation technique, which requires modest conditions. In this process, a mixture of MoS(2) and molybdenum dioxide (MoO(2)) is produced by evaporating sulfur powder and molybdenum trioxide (MoO(3)) nano-particles simultaneously. Further annealing in a sulfur-rich environment transforms majority of the excess MoO(2) into layered MoS(2). The deposited MoS(2) is then mechanically exfoliated into minimum resolvable atomically thin layers, which are characterized using micro-Raman spectroscopy and atomic force microscopy. Furthermore Raman spectroscopy is employed to determine the effect of electrochemical lithium ion exposure on atomically thin layers of MoS(2). PMID:22064926

Balendhran, Sivacarendran; Ou, Jian Zhen; Bhaskaran, Madhu; Sriram, Sharath; Ippolito, Samuel; Vasic, Zoran; Kats, Eugene; Bhargava, Suresh; Zhuiykov, Serge; Kalantar-Zadeh, Kourosh

2011-11-07

147

A simple method to make an electrical connection between ZnO microwire and substrate through nanoscale metal evaporation  

NASA Astrophysics Data System (ADS)

We developed a simple method to make an electrical connection with nanoscale electrodes on microscale wire using suspended Poly(methyl methacrylate) (PMMA) strings. Less than 90 nm height of Ti/Au made a complete electrical connection on the ZnO microwires of which diameter is around 2 ?m. A cross linked PMMA string was bridged between ZnO microwire and substrate for making good electrical connection. The contact resistance of ZnO microwire fabricated by this method was much lower than that of device fabricated by standard E-beam lithography and evaporation. This fabrication method is readily extendible to prepare nano scale electrodes on various micro sized materials and serves as a pathway for studying their mesoscopic transport phenomena.

Kim, Hakseong; Lee, Jinkyung; Yun, Hoyeol; Lee, Sang Wook

2013-03-01

148

Cascade multicomponent cooling method for liquefying natural gas  

SciTech Connect

A cooling arrangement to be used in liquefying natural gas and in similar applications and having an incorporated cascade circuit with a fractional condensation of a cooling medium and with separation of the phases of the cooling medium, has such a lay-out and is so operated that the warming-up of the expanded cooling medium in a countercurrent evaporative heat exchange and the warming-up of the expanded cooling medium in a countercurrent supercooling heat exchange are in parallel to one another. The separated gaseous phase of the cooling medium is cooled in the countercurrent evaporative heat exchange to be at least partially condensed. The countercurrent supercooling heat exchange and the countercurrent evaporative heat exchange are thermally segregated from one another.

Krieger, H.

1981-12-01

149

Metallization: Evaporation  

NSDL National Science Digital Library

This website includes an animation depicting an overview of the metallization evaporation processes. Objective: Identify the process of evaporation. This simulation is from Module 061 of the Process & Equipment II Cluster of the MATEC Module Library (MML). You can find this animation under the section "Process & Equipment II." To view other clusters or for more information about the MML visit http://matec.org/ps/library3/process_I.shtml

2012-10-05

150

A general method of parameterizing the big-leaf model to predict the dry-canopy evaporation rate of individual coniferous forest stands  

NASA Astrophysics Data System (ADS)

This study proposes a general method of parameterizing the big-leaf model that is applicable to estimation of daytime dry-canopy evaporation (hereafter, evaporation) rates of coniferous forest stands without observed flux data. The method considers variation in the reference value of surface conductance Gs between individual stands by incorporating a relationship between canopy height and reference Gs values reported by Komatsu (2003c) [Hydrological Processes 17: 2503-2512]. However, the method does not consider variation in modifier functions of Gs and in aerodynamic conductance Ga between individual stands. We examined the validity of the method based on daytime evaporation rate data for 26 coniferous stands. The method showed greater predictability than another method that ignores variation in reference Gs values between individual stands. This illustrates the validity of considering variation in reference Gs values between individual stands. Model predictability was not enhanced by considering variation in modifier functions of Gs and Ga between individual stands. This illustrates the validity of ignoring variation in modifier functions of Gs and Ga between individual stands. The method is applicable to stands with projected LAI ? 3.0 and canopy height method can result in errors when applied outside these limitations. Regardless, the method should be valuable for estimating daytime evaporation rates of coniferous stands, as many stands fall within these limitations. The method is applicable to evaporation rate estimates in growing seasons without soil water stress when dry-canopy evaporation significantly affects the forest water cycle. At this stage, the method can result in errors when applied outside this limitation. However, the method should be valuable as a basis for developing a more comprehensive method applicable outside this limitation.

Komatsu, Hikaru

2004-11-01

151

A Model for Modification of Air in a Small Town by Using the Evaporative Cooling Method.  

NASA Astrophysics Data System (ADS)

In this study a new model for quantifying the effect of evaporative cooling produced by the evapotranspiration from trees on the air temperature of Ali- Al Sharqi town, south of Iraq, (lat. 32.1 ° N, long 46.85 ° E) was suggested. The ASCE and FAO Penman Monteith model was used to calculate the actual evapotranspiration from a tree in the selected town. The dispersion of moisture from trees in the neighborhood in the three dimensions by using the Gaussian dispersion model was estimated. The decreasing of air temperature due to the moisture added by trees on a specific control volume was calculated by using the psychometric chart. The maximum cooling degree achieved by the suggested model reached to 2.6 ° C in July while minimum value was (1.8 ° C) and appeared in April. The results of applying the model on a hot and dry day indicated that the higher cooling degree can be obtained reach to 3.6 ° C at the noon time

Shayia, Alaa Motar

2012-06-01

152

Structural and Optical Characterization of CdS:Fe Thin Films Prepared by Flash Evaporation Method  

NASA Astrophysics Data System (ADS)

CdS thin layers of 250 nm thick doped with zero, 0.1, 0.2 and 0.3 weight percents iron were deposited on glass substrates by modified flash evaporation technique in vacuum at the pressure of 5 × 10-6 mbar. The structure of the films was investigated by X-ray diffractometry. It was revealed that the films had hexagonal structure with (002) preferred orientation. Field emission scanning electron microscopy (FESEM) was employed to study the surface morphology of the prepared samples. It was found from FESEM images that the Fe-doped CdS film showed more surface uniformity. Optical absorption data of the films were used to measure the band gap of the films. It was found that the band gap of the samples decreased upon increasing the Iron concentration. Photoluminescence (PL) spectra of the CdS:Fe thin films were used to study most prominent excitation peaks within the energy range (1.6-2.6 eV). The variation in peak energy was observed upon increasing the Fe content in the films.

Dizaji, H. R.; Ghasemian, M.; Ehsani, M. H.

2012-04-01

153

The E J characteristics of MgB2 thin film prepared by electron beam evaporation method  

NASA Astrophysics Data System (ADS)

The E J characteristics of MgB2 thin film prepared by the electron beam evaporation method were investigated. The film has a fairly higher Tc of 35 K and Jc of 0.48 MA/cm2 at 20 K and 1 T among as-grown MgB2 films prepared by various methods. The E J characteristics at various temperatures and magnetic fields can be described by the percolation transition model. The pinning parameters and the distribution of pinning forces of the MgB2 thin film were estimated. It was found that the MgB2 thin film has the uniform distribution of pinning forces by grain boundaries.

Haruta, Masakazu; Fujiyoshi, T.; Sueyoshi, T.; Miyahara, K.; Doi, T.; Kitaguchi, H.

2005-10-01

154

Children's understanding of changes of state involving the gas state, Part 2: Evaporation and condensation below boiling point  

Microsoft Academic Search

Deriving from a three?year longitudinal study which explored the development of children's concept of a substance (ages 11 to 14), part 2 of this paper (see Johnson 1998b) reports findings in relation to evaporation at room temperature and condensation of atmospheric water vapour. Part one had reported findings in relation to boiling water and the development of pupils’ understanding of

Philip Johnson

1998-01-01

155

Spectroscopic methods in gas hydrate research.  

PubMed

Gas hydrates are crystalline structures comprising a guest molecule surrounded by a water cage, and are particularly relevant due to their natural occurrence in the deep sea and in permafrost areas. Low molecular weight molecules such as methane and carbon dioxide can be sequestered into that cage at suitable temperatures and pressures, facilitating the transition to the solid phase. While the composition and structure of gas hydrates appear to be well understood, their formation and dissociation mechanisms, along with the dynamics and kinetics associated with those processes, remain ambiguous. In order to take advantage of gas hydrates as an energy resource (e.g., methane hydrate), as a sequestration matrix in (for example) CO(2) storage, or for chemical energy conservation/storage, a more detailed molecular level understanding of their formation and dissociation processes, as well as the chemical, physical, and biological parameters that affect these processes, is required. Spectroscopic techniques appear to be most suitable for analyzing the structures of gas hydrates (sometimes in situ), thus providing access to such information across the electromagnetic spectrum. A variety of spectroscopic methods are currently used in gas hydrate research to determine the composition, structure, cage occupancy, guest molecule position, and binding/formation/dissociation mechanisms of the hydrate. To date, the most commonly applied techniques are Raman spectroscopy and solid-state nuclear magnetic resonance (NMR) spectroscopy. Diffraction methods such as neutron and X-ray diffraction are used to determine gas hydrate structures, and to study lattice expansions. Furthermore, UV-vis spectroscopic techniques and scanning electron microscopy (SEM) have assisted in structural studies of gas hydrates. Most recently, waveguide-coupled mid-infrared spectroscopy in the 3-20 ?m spectral range has demonstrated its value for in situ studies on the formation and dissociation of gas hydrates. This comprehensive review summarizes the importance of spectroscopic analytical techniques to our understanding of the structure and dynamics of gas hydrate systems, and highlights selected examples that illustrate the utility of these individual methods. PMID:22094590

Rauh, Florian; Mizaikoff, Boris

2011-11-18

156

Thermal patterns in evaporating liquid  

Microsoft Academic Search

In this paper, some of the preparatory experiments of the ESA sponsored space program CIMEX-1 are presented. A liquid layer\\u000a of variable thickness is subject to a flow of inert gas. The non-uniform evaporation induced by the gas flow creates a temperature\\u000a gradient parallel to the interface triggering in that way thermocapillary convection. The combined action of evaporation,\\u000a thermocapillarity and

Carlo S. Iorio; Oleg A. Kabov; Jean-Claude Legros

2007-01-01

157

Hydrogen gas sensor and method of manufacture  

DOEpatents

A sensor for measuring the pressure of hydrogen gas in a nuclear reactor, and method of manufacturing the same. The sensor comprises an elongated tube of hydrogen permeable material which is connected to a pressure transducer through a feedthrough tube which passes through a wall at the boundary of the region in which hydrogen is present. The tube is pressurized and flushed with hydrogen gas at an elevated temperature during the manufacture of the sensor in order to remove all gasses other than hydrogen from the device.

McKee, John M. (Hinsdale, IL)

1991-01-01

158

Evaporating droplets  

NASA Astrophysics Data System (ADS)

In our everyday life we are constantly confronted with evaporating drops and the consequences of it. The seemingly simple problem of an evaporating droplet has attracted a great deal of attention over the past years. The problem is complicated due to the fact that the form of the droplet during the evaporation is a priori unknown, and due to the large number of effects that have to be taken into account (temperature, convection, Marangoni effects). We consider the very simple situation of the evaporation of a perfectly wetting liquid on a molecularly smooth surface. The radius R(t) of the droplet is followed in time until it reaches zero. If the evaporation is purely diffusive, a radius that decreases as the square root of time is expected; this is indeed found for organic liquids, but water has a different exponent. We show that the difference is likely to be due to the fact that water vapor is lighter than air, and the vapor of other liquids more dense. If we carefully confine the water so that the diffusive boundary layer may develop, we retrieve the square root of time behavior. On the other hand, if we force convection for an organic liquid, we retrieve the anomalous exponent for water.

Shahidzadeh-Bonn, Noushine; Rafai, Salima; Azouni, Aza; Bonn, Daniel

2006-03-01

159

Energy conservation practices - vertical tube foam evaporation  

Microsoft Academic Search

This paper describes the vertical tube foam evaporation (VTFE) of aqueous liquids which reduces energy requirements by enhancing the evaporation coefficient, which permits the use of a lower temperature difference, to drive the evaporation process. The VTFE method relies on imposing a foamy mode of flow of the evaporating liquid over the heat transfer surface or tube-side wall. This mode

Sephton

1981-01-01

160

Development of a new laboratory evaporation measurement device as decision support for evaporation-optimized building  

Microsoft Academic Search

A new laboratory evaporation measurement device (LEMD) was developed to estimate the evaporation rates of urban surface materials. Here, evaporation is induced by means of a constant heat input and airflow. The evaporation can be measured using two different methods concurrently. Method 1 is based on a balance, which measures the mass loss over time. In method 2 the water

P. Starke; C. Wallmeyer; S. Rölver; P. Göbel; W. G. Coldewey

161

Evaporative instabilities  

NASA Astrophysics Data System (ADS)

Evaporation plays a major role in many industrial and physical processes ranging from heat pipes and the drying of magnetic films to the drying of the tear film in the eye. We investigated, theoretically, the gravity and surface tension gradient-driven instabilities occurring during the evaporation of a liquid into its own vapor taking into account the fluid dynamics of both phases. The liquid and its vapor are assumed to be confined between two horizontal plates, and different heating arrangements are applied. The effects of fluid layer depths, the evaporation rate and the temperature gradient applied across the fluids on the stability of the interface are studied. The modes of the flow pattern are determined for each scenario. The physics of the instability are explained and a comparison is made with the results of similar, yet different problems.

Ozen, O.

162

Method for producing evaporation inhibiting coating for protection of silicon--germanium and silicon--molybdenum alloys at high temperatures in vacuum  

DOEpatents

A method is given for protecting Si--Ge and Si-- Mo alloys for use in thermocouples. The alloys are coated with silicon to inhibit the evaporation of the alloys at high tempenatures in a vacuum. Specific means and methods are provided. (5 fig) (Official Gazette)

Chao, P.J.

1974-01-01

163

Web Substrate Heating and a Thermodynamic Calculation Method for Li Film Thickness in a Thermal Evaporation System  

Microsoft Academic Search

Substrate heating and deposition rate have been modeled for the thermal evaporation of Lithium in a vacuum web coating system. To aid in modeling the substrate heat load due to the Li deposition process a novel, self- consistent, thermodynamic model was developed that allows calculation of the deposition rate (for Li or any material) as a function of only evaporator

J. Affinito; M. J. McCann; C. Sheehan; S. Bullock

2001-01-01

164

a Novel Method for Gas Sensors Characterization  

NASA Astrophysics Data System (ADS)

For E-nose applications, sensors are never specified towards the aroma chemicals, because it is difficult to generate a known amount of chemical vapours from a condensed phase. A method was developed, that allows the specification of gas sensors towards food samples, using a GC/sensors coupling. We have found the ADL lower than the GC-FID detector, and an unexpected response for E.V. Olive Oil.

Mielle, P.; Marquis, F.; Trivier, V.

2000-12-01

165

A new method for the determination of biogenic amines in cheese by LC with evaporative light scattering detector.  

PubMed

This paper presents a new LC method with evaporative light scattering detection (ELSD), for the separation and determination of the biogenic amines (histamine, spermidine, spermine, tyramine, putrescine and ?-phenylethylamine) which are commonly present in cheese, as their presence and relative amounts give useful information about freshness, level of maturing, quality of storage and cheese authentication. The LC-ELSD method is validated by comparison of the results with those obtained through LC-UV determination, based on a pre-column dansyl chloride derivatisation step. The obtained data demonstrate that both methods can be interchangeably used for biogenic amines determination in cheese. The new LC-ELSD method shows good precision and permits to achieve, for standard solutions, limit of detection (LOD) values ranging from 1.4 to 3.6 mg L(-1) and limit of quantitation (LOQ) values ranging from 3.6 to 9.3 mg L(-1). The whole methodology, comprehensive of the homogenization-extraction process and LC-ELSD analysis, has been applied in the analysis of a typical Calabria (Southern Italy) POD cheese, known as Caciocavallo Silano. The most aboundant amine found was histamine, followed, in decreasing order, by tyramine, spermine, putrescine, ?-phenylethylamine and spermidine, for a total amount of 127 mg kg(-1). This value does not represent a possible risk for consumer health, according to the toxicity levels reported in literature and regarded as acceptable. PMID:21645711

Restuccia, Donatella; Spizzirri, U Gianfranco; Puoci, Francesco; Cirillo, Giuseppe; Curcio, Manuela; Parisi, Ortensia I; Iemma, Francesca; Picci, Nevio

2011-04-05

166

A New Method on Measuring Moisture Content in Gas  

Microsoft Academic Search

A new method on measuring moisture content in gas with high accuracy is presented. Fibreglass is filled in a filter tube fixed in the sampling pipe. Mist of gas will be intercepted by the fibreglass when the gas flows through the sampling tube filled with fibreglass. Moisture content in gas can be calculated on condition that volume of gas flowing

Xiao Lichun; Li Qiang; Ding Zhijiang; Yang Jingfei

2009-01-01

167

Development of a thermal evaporation cell for gas-phase infrared absorption spectroscopy of compounds with low volatility.  

PubMed

To facilitate in-depth hazard prediction models, we must understand the spectral properties of expulsion plumes from conventional weapon attacks. Precise data on the spectral absorption of three chemical weapon agent simulants, in the infrared regime, are required to properly determine the mass of simulant in expulsion plumes from field demonstrations and small scale tests. Data for triethyl phosphate (a Soman simulant), triethyl phosphite (a Sarin simulant), and tributyl phosphate (a VX simulant) are presented. A thermal evaporation cell was designed and built that incorporated features that are not commercially available. PMID:18028706

Ingram, John M; Fountain, Augustus W

2007-11-01

168

Utility of Penman Monteith, Priestley Taylor, reference evapotranspiration, and pan evaporation methods to estimate pasture evapotranspiration  

Microsoft Academic Search

Actual evapotranspiration (ETa) was measured at 30-min resolution over a 19-month period (September 28, 2000 April 23, 2002) from a nonirrigated pasture site in Florida, USA, using eddy correlation methods. The relative magnitude of measured ETa (about 66% of long-term annual precipitation at the study site) indicates the importance of accurate ETa estimates for water resources planning. The time and

David M. Sumner; Jennifer M. Jacobs

2005-01-01

169

A Robust Moment Method for Evaluation of the Disappearance Rate of Evaporating Sprays  

Microsoft Academic Search

In this paper we tackle a critical issue in the numerical modeling, by Eulerian moment methods, of polydisperse multiphase systems, constituted of dispersed particles or droplets, a general class of systems which include aerosols. Their modeling starts at a mesoscopic scale with an equation on the number density function NDF of particles\\/droplets which satisfies a population balance equation. (PBE, also

Marc Massot; Frédérique Laurent; Damien Kah; Stéphane de Chaisemartin

2010-01-01

170

Vacuum flash evaporated polymer composites  

DOEpatents

A method for fabrication of polymer composite layers in a vacuum is disclosed. More specifically, the method of dissolving salts in a monomer solution, vacuum flash evaporating the solution, condensing the flash evaporated solution as a liquid film, and forming the condensed liquid film into a polymer composite layer on a substrate is disclosed.

Affinito, J.D.; Gross, M.E.

1997-10-28

171

Gas sensing method applicable to real conditions  

NASA Astrophysics Data System (ADS)

In this work, we tested the influence of various sampling techniques and modes of operation on the response of sensor systems under real conditions. The first system was based on diffusive sampling. The second one used a dynamic method of sampling. In the third system, a stop flow mode of operation was applied. A considerable error of target gas concentration assessment was obtained in the first two cases. The error resulted from sensor signal fluctuations encountered during their exposure either to the air at the measurement point (diffusive sampling) or to the air drawn from the measurement point (dynamic sampling). The fluctuations could be attributed to the temporal variation of physical and chemical parameters of air. The main merit of the third method consists in utilizing sensor exposure under the conditions of stopped flow for the purpose of pollutant concentration assessment. While using this method, the accuracy of target gas quantification under real conditions was comparable to the one achieved when measuring standard gases. We think that the proposed method is a valuable contribution, which addresses the increasing demand for sensor systems that perform quantitative pollution assessment in workplace air, under real conditions. This paper was presented at the Conference on Optoelectronic and Electronic Sensors held in Karpacz, Poland, on 24-27 June 2012.

Szczurek, A.; Maciejewska, M.

2013-04-01

172

Direct determination of kanamycin in raw materials, veterinary formulation and culture media using a novel liquid chromatography–evaporative light scattering method  

Microsoft Academic Search

A novel method for the direct determination of kanamycin A and its minor component kanamycin B was developed and validated based on reversed phase liquid chromatography with evaporative light scattering detector (ELSD). ELSD response to kanamycins was found to be enhanced by: (a) decrease of peak width and asymmetry (obtained by controlling the mobile phase acidity or ratio of organic

N. C. Megoulas; M. A. Koupparis

2005-01-01

173

Estimation of evaporative fraction from a combination of day and night land surface temperatures and NDVI: A new method to determine the Priestley–Taylor parameter  

Microsoft Academic Search

Satellite remote sensing is a promising technique to estimate global or regional evapotranspiration (ET) or evaporative fraction (EF) of the surface total net radiation budget. The current methods of estimating the ET (or EF) from the gradient between land surface temperature (Ts) and near surface air temperature are very sensitive to the retrieval errors of Ts and the interpolation errors

Kaicun Wang; Zhanqing Li; M. Cribb

2006-01-01

174

Waste Water Evaporation Process for Fertilizer Production Technology by the ODDA Method. Compendium on Low- and Non-Waste Technology.  

National Technical Information Service (NTIS)

NPK fertilizers, a nitro-phosphate type fertilizer, is produced through the Norsk-Hydro-ODDA technology. This technology has been modified to incorporate an effective wastewater evaporator system which reduces the amount of contaminated cooling water disc...

1982-01-01

175

Rapid method for the simultaneous measurement of nicotine and cotinine in urine and serum by gas chromatography-mass spectrometry.  

PubMed

A simple, sensitive, and rapid gas chromatographic-mass spectrometric method is described for the simultaneous detection and quantitation of nicotine and its metabolite, cotinine, in urine and serum. The analytes and their respective deuterated internal standards were extracted by liquid-liquid extraction coupled to centrifugation and evaporation. The detection limit of the assay was 0.16 ng/ml for both nicotine and cotinine. The limit of quantitation for each analyte was 1.25 ng/ml. PMID:9653950

James, H; Tizabi, Y; Taylor, R

1998-04-24

176

Release kinetic studies of aspirin microcapsules from ethyl cellulose, cellulose acetate phthalate and their mixtures by emulsion solvent evaporation method.  

PubMed

The present study was oriented towards microencapsulation of aspirin and the study of its release kinetics. The desired encapsulation was achieved by emulsion solvent evaporation method using ethyl cellulose (EC), cellulose acetate phthalate (CAP) and their mixture (1:1) of polymeric constituents. Characterization of the formulations was performed by size, shape, drug loading efficiency and in-vitro drug release analysis. The in-vitro release profiles from different polymeric microcapsules were applied on different kinetic models. The prepared microcapsules were found free flowing and almost spherical in shape with particle sizes ranging from 300â700Îm, having a loading efficiency of 75â85%. The best fit model with the highest correlation coefficient was observed in Higuchi model, indicating diffusion controlled principle. The n value obtained from Korsemeyer-Peppas model varied between 0.5â0.7, confirming that the mechanism of drug release was diffusion controlled. Comparative studies revealed that the release of aspirin from EC microcapsules was slower as compared to that of CAP and their binary mixture. PMID:21179372

Dash, Vikas; Mishra, Sujeet K; Singh, Manoj; Goyal, Amit K; Rath, Goutam

2009-12-19

177

Release Kinetic Studies of Aspirin Microcapsules from Ethyl Cellulose, Cellulose Acetate Phthalate and their Mixtures by Emulsion Solvent Evaporation Method  

PubMed Central

The present study was oriented towards microencapsulation of aspirin and the study of its release kinetics. The desired encapsulation was achieved by emulsion solvent evaporation method using ethyl cellulose (EC), cellulose acetate phthalate (CAP) and their mixture (1:1) of polymeric constituents. Characterization of the formulations was performed by size, shape, drug loading efficiency and in-vitro drug release analysis. The in-vitro release profiles from different polymeric microcapsules were applied on different kinetic models. The prepared microcapsules were found free flowing and almost spherical in shape with particle sizes ranging from 300–700?m, having a loading efficiency of 75–85%. The best fit model with the highest correlation coefficient was observed in Higuchi model, indicating diffusion controlled principle. The n value obtained from Korsemeyer-Peppas model varied between 0.5–0.7, confirming that the mechanism of drug release was diffusion controlled. Comparative studies revealed that the release of aspirin from EC microcapsules was slower as compared to that of CAP and their binary mixture.

Dash, Vikas; Mishra, Sujeet K.; Singh, Manoj; Goyal, Amit K.; Rath, Goutam

2010-01-01

178

Influence of Sb in synthesize of ZnO nanowire using sandwich type substrate in carbothermal evaporation method  

NASA Astrophysics Data System (ADS)

The paper deals with synthesis of Sb doped ZnO nanowire by considering Si coated with Sb and Au as substrate using carbothermal evaporation method. The horizontally oriented Sb doped ZnO nanowires with a diameter of 1 ?m synthesized at 900 °C, which is quite high as compared to the Pure ZnO nanowires generated without the influence of Sb at 900 °C. The nanowire synthesized at 900 °C showed a measurable lower angle of about 0.06° from XRD and suppression of A1T and E1(L0) modes in Raman spectroscopic, this confirms the incorporation of Sb in ZnO lattice. The strong exciton emission and weak deep-level emission from room temperature PL and Strong emission attributed to the radiant recombination from neutral-acceptor-bound exciton (A0X) peak accompanied by two strong and broad emission of donor acceptor pair (DAP) from low temperature PL, this confirms the use of Sb as an acceptor for ZnO.

Palani, I. A.; Okazaki, K.; Nakamura, D.; Sakai, K.; Higashihata, M.; Okada, T.

2012-02-01

179

Comparison of methods for measuring gas-particle partitioning of semivolatile compounds  

NASA Astrophysics Data System (ADS)

This work demonstrates several difficulties associated with sampling semivolatile aerosols. Gas-particle partition coefficients ( Kp=[ F/TSP]/ A) of semivolatile PAHs and alkanes were estimated from chamber tests using four different sampling methods: filter-adsorbent (FA), filter-filter-adsorbent (FFA), Denuder-filter-adsorbent (DFA), and electrostatic precipitator-Adsorbent (EA). The FA, FFA, and EA sampling methods estimated Kp accurately for high concentrations of PAHs in diesel engine exhaust aerosol. The FA sampler, which used a Teflon Zeflour filter, was biased by filter adsorption of alkane gases sampled at lower concentrations, whereas the FFA sampler, which used a Teflon coated glass fiber filter, was biased by particle evaporation during the same tests. The EA sampler introduced small biases at low concentrations due to chemical artifacts from the corona, non-ideal particle collection, and evaporative loss of collected particles. The DFA sampler was biased by particle losses in the denuder for PAHs in diesel exhaust aerosol, but gave accurate estimates of Kp for alkanes measured at lower concentrations. Results from this research show that none of the methods tested was able to measure gas-particle partition coefficients accurately for each series of compounds under all sampling situations.

Volckens, John; Leith, David

180

On-line high-performance liquid chromatography-solvent evaporation - high-performance liquid chromatography - capillary gas chromatography - flame ionisation detection for the analysis of mineral oil polyaromatic hydrocarbons in fatty foods  

Microsoft Academic Search

An automated on-line method is described that involves a first LC separation on a large column, evaporation of a 6-ml fraction in an on-line solvent evaporator, a second LC separation using a different mobile phase, fractionating the components of interest and transfer to GC through the in-line vaporiser\\/overflow interface. The method is designed for the injection of a large amount

Sabrina Moret; Konrad Grob; L. S. Conte

1996-01-01

181

Water augmented indirectly-fired gas turbine systems and method  

DOEpatents

An indirectly-fired gas turbine system utilizing water augmentation for increasing the net efficiency and power output of the system is described. Water injected into the compressor discharge stream evaporatively cools the air to provide a higher driving temperature difference across a high temperature air heater which is used to indirectly heat the water-containing air to a turbine inlet temperature of greater than about 1,000.degree. C. By providing a lower air heater hot side outlet temperature, heat rejection in the air heater is reduced to increase the heat recovery in the air heater and thereby increase the overall cycle efficiency.

Bechtel, Thomas F. (Lebanon, PA); Parsons, Jr., Edward J. (Morgantown, WV)

1992-01-01

182

Water augmented indirectly-fired gas turbine system and method  

DOEpatents

An indirectly-fired gas turbine system utilizing water augmentation for increasing the net efficiency and power output of the system is described. Water injected into the compressor discharge stream evaporatively cools the air to provide a high driving temperature difference across a high temperature air heater which is used to indirectly heat the water-containing air to a turbine inlet temperature of greater than about 1000{degrees}C. By providing a lower air heater hot side outlet temperature, heat rejection in the air heater is reduced to increase the heat recovery in the air heater and thereby increase the overall cycle efficiency.

Bechtel, T.F.; Parsons, E.J. Jr.

1991-12-31

183

Water augmented indirectly-fired gas turbine system and method  

DOEpatents

An indirectly-fired gas turbine system utilizing water augmentation for increasing the net efficiency and power output of the system is described. Water injected into the compressor discharge stream evaporatively cools the air to provide a high driving temperature difference across a high temperature air heater which is used to indirectly heat the water-containing air to a turbine inlet temperature of greater than about 1000[degrees]C. By providing a lower air heater hot side outlet temperature, heat rejection in the air heater is reduced to increase the heat recovery in the air heater and thereby increase the overall cycle efficiency.

Bechtel, T.F.; Parsons, E.J. Jr.

1991-01-01

184

Method for gas-metal arc deposition  

DOEpatents

Method and apparatus for gas-metal arc deposition of metal, metal alloys, and metal matrix composites are disclosed. The apparatus contains an arc chamber for confining a D.C. electrical arc discharge, the arc chamber containing an outlet orifice in fluid communication with a deposition chamber having a deposition opening in alignment with the orifice for depositing metal droplets on a coatable substrate. Metal wire is passed continuously into the arc chamber in alignment with the orifice. Electric arcing between the metal wire anode and the orifice cathode produces droplets of molten metal from the wire which pass through the orifice and into the deposition chamber for coating a substrate exposed at the deposition opening. When producing metal matrix composites, a suspension of particulates in an inert gas enters the deposition chamber via a plurality of feed openings below and around the orifice so that reinforcing particulates join the metal droplets to produce a uniform mixture which then coats the exposed substrate with a uniform metal matrix composite. 1 fig.

Buhrmaster, C.L.; Clark, D.E.; Smartt, H.B.

1990-11-13

185

A laboratory study on the uptake of HCl, HNO 3, and SO 2 gas by ice crystals and the effect of these gases on the evaporation rate of the crystals  

Microsoft Academic Search

The results of our new and earlier laboratory studies on the uptake of gases by ice crystals are summarized in terms of (1) the equilibrium phase diagram for a system gas\\/H2O, (2) the effect of these gases on the evaporation rate of ice crystals, and (3) in terms of the uptake of the gases by water drops. It is shown

K Diehl; S. K Mitra; H. R Pruppacher

1998-01-01

186

Testing an in-line digital holography ‘inverse method’ for the Lagrangian tracking of evaporating droplets in homogeneous nearly isotropic turbulence  

NASA Astrophysics Data System (ADS)

An in-line digital holography technique is tested, the objective being to measure Lagrangian three-dimensional (3D) trajectories and the size evolution of droplets evaporating in high-Re? strong turbulence. The experiment is performed in homogeneous, nearly isotropic turbulence (50 × 50 × 50 mm3) created by the meeting of six synthetic jets. The holograms of droplets are recorded with a single high-speed camera at frame rates of 1-3 kHz. While hologram time series are generally processed using a classical approach based on the Fresnel transform, we follow an ‘inverse problem’ approach leading to improved size and 3D position accuracy and both in-field and out-of-field detection. The reconstruction method is validated with 60 ?m diameter water droplets released from a piezoelectric injector ‘on-demand’ and which do not appreciably evaporate in the sample volume. Lagrangian statistics on 1000 reconstructed tracks are presented. Although improved, uncertainty on the depth positions remains higher, as expected in in-line digital holography. An additional filter is used to reduce the effect of this uncertainty when calculating the droplet velocities and accelerations along this direction. The diameters measured along the trajectories remain constant within ±1.6%, thus indicating that accuracy on size is high enough for evaporation studies. The method is then tested with R114 freon droplets at an early stage of evaporation. The striking feature is the presence on each hologram of a thermal wake image, aligned with the relative velocity fluctuations ‘seen’ by the droplets (visualization of the Lagrangian fluid motion about the droplet). Its orientation compares rather well with that calculated by using a dynamical equation for describing the droplet motion. A decrease of size due to evaporation is measured for the droplet that remains longest in the turbulence domain.

Chareyron, D.; Marié, J. L.; Fournier, C.; Gire, J.; Grosjean, N.; Denis, L.; Lance, M.; Méès, L.

2012-04-01

187

Simple gas chromatographic method for furfural analysis.  

PubMed

A new, simple, gas chromatographic method was developed for the direct analysis of 5-hydroxymethylfurfural (5-HMF), 2-furfural (2-F) and 5-methylfurfural (5-MF) in liquid and water soluble foods, using direct immersion SPME coupled to GC-FID and/or GC-TOF-MS. The fiber (DVB/CAR/PDMS) conditions were optimized: pH effect, temperature, adsorption and desorption times. The method is simple and accurate (RSD<8%), showed good recoveries (77-107%) and good limits of detection (GC-FID: 1.37 microgL(-1) for 2-F, 8.96 microgL(-1) for 5-MF, 6.52 microgL(-1) for 5-HMF; GC-TOF-MS: 0.3, 1.2 and 0.9 ngmL(-1) for 2-F, 5-MF and 5-HMF, respectively). It was applied to different commercial food matrices: honey, white, demerara, brown and yellow table sugars, and white and red balsamic vinegars. This one-step, sensitive and direct method for the analysis of furfurals will contribute to characterise and quantify their presence in the human diet. PMID:18976770

Gaspar, Elvira M S M; Lopes, João F

2008-10-17

188

Undersaturation dependence of the evaporation rate of potassium chloride  

Microsoft Academic Search

Theories of ledge dynamics for crystals evaporating by the stepwise mechanism predict a change from crystal edge control to dislocation control of the evaporation kinetics as the gas phase saturation is reduced. This effect was studied by measuring the rate of evaporation from the (100) face of high purity KCl crystals vs gas phase saturation with a specially designed spherical

Paul C. Nordine; Paul W. Gilles

1981-01-01

189

System and method for detecting gas  

DOEpatents

A system to detect a presence of a specific gas in a mixture of gaseous byproducts comprising moisture vapor is disclosed. The system includes an electrochemical cell, a transport to deliver the mixture of gaseous byproducts from the electrochemical cell, a gas sensor in fluid communication with the transport, the sensor responsive to a presence of the specific gas to generate a signal corresponding to a concentration of the specific gas, and a membrane to prevent transmission of liquid moisture, the membrane disposed between the transport and the gas sensor.

Chow, Oscar Ken (Simsbury, CT); Moulthrop, Lawrence Clinton (Windsor, CT); Dreier, Ken Wayne (Madison, CT); Miller, Jacob Andrew (Dexter, MI)

2010-03-16

190

Method for mapping a natural gas leak  

DOEpatents

A system is described that is suitable for use in determining the location of leaks of gases having a background concentration. The system is a point-wise backscatter absorption gas measurement system that measures absorption and distance to each point of an image. The absorption measurement provides an indication of the total amount of a gas of interest, and the distance provides an estimate of the background concentration of gas. The distance is measured from the time-of-flight of laser pulse that is generated along with the absorption measurement light. The measurements are formatted into an image of the presence of gas in excess of the background. Alternatively, an image of the scene is superimposed on the image of the gas to aid in locating leaks. By further modeling excess gas as a plume having a known concentration profile, the present system provides an estimate of the maximum concentration of the gas of interest.

Reichardt, Thomas A. (Livermore, CA); Luong, Amy Khai (Dublin, CA); Kulp, Thomas J. (Livermore, CA); Devdas, Sanjay (Albany, CA)

2009-02-03

191

Counterion evaporation  

SciTech Connect

We study the adsorption behavior of a highly charged rodlike polyelectrolyte approaching an oppositely charged planar wall in an unbounded electrolyte solution. The grand potential, the entropy, and the total number of screening particles are calculated as functions of the rod-wall distance, using input parameters that are typical of a DNA-molecule and charged lipid bilayers. It is found that counterions which are bound to the polyelectrolyte at infinite rod-wall distances will be released, or {open_quotes}evaporated,{close_quotes} as the DNA molecule moves closer to the charged wall. This effect can be regarded as the opposite of the ion-condensation process. The transition of ions from the system of screening ions into the reservoir of bulk ions can lead to an increase of the enthalpy. This gain of enthalpy for the whole system manifests itself as an attractive contribution to the effective interaction between the wall and the polyelectrolyte.

Fleck, C.; von Grunberg, H. H.

2001-06-01

192

Olive mill wastewater evaporation management using PCA method Case study of natural degradation in stabilization ponds (Sfax, Tunisia).  

PubMed

Olive mill wastewater (OMW) evaporation ponds management was investigated in five serial evaporation open-air multiponds of 50 ha located in Sfax (Tunisia). Physico-chemical parameters and microbial flora evolution were considered. Empirical models describing the OMW characteristic changes with the operation time were established and Principal Component Analysis (PCA) described the correlation between physico-chemical and biological parameters. COD, BOD, total solids, polyphenols and electrical conductivity exhibited first-order models. Four groups exhibited high correlations. The first included temperature, density, COD, TSS, TS, BOD, VS, TOC, TKN, polyphenols and minerals. The second group was made up of yeasts and moulds. The third group was established with phenolic compounds, total sugars, fats, total phosphorous, NH(4)(+) and pH. The fourth group was constituted by exclusively aerobic bacteria. Bacterial-growth toxic effect was exhibited by high organic load, ash content and polyphenols, whereas moulds and yeasts were more adapted to OMW. During the storage, all the third group parameter values decreased and were inversely related to the others. In the last pond, COD, BOD, TS and TSS rates were reduced by 40%, 50%, 50% and 75% respectively. The evaporation and the biological activity were the main processes acting, predicting the OMW behavior during evaporation in air-open ponds. PMID:20036054

Jarboui, Raja; Sellami, Fatma; Azri, Chafai; Gharsallah, Néji; Ammar, Emna

2009-12-03

193

Method and apparatus for preventing overspeed in a gas turbine  

DOEpatents

A method and apparatus for preventing overspeed in a gas turbine in response to the rapid loss of applied load is disclosed. The method involves diverting gas from the inlet of the turbine, bypassing the same around the turbine and thereafter injecting the diverted gas at the turbine exit in a direction toward or opposing the flow of gas through the turbine. The injected gas is mixed with the gas exiting the turbine to thereby minimize the thermal shock upon equipment downstream of the turbine exit.

Walker, William E. (San Diego, CA)

1976-01-01

194

Full evaporation dynamic headspace in combination with selectable one-dimensional/two-dimensional gas chromatography-mass spectrometry for the determination of suspected fragrance allergens in cosmetic products.  

PubMed

Suspected fragrance allergens were determined in cosmetic products using a combination of full evaporation-dynamic headspace (FEDHS) with selectable one-dimensional/two-dimensional GC-MS. The full evaporation dynamic headspace approach allows the non-discriminating extraction and injection of both apolar and polar fragrance compounds, without contamination of the analytical system by high molecular weight non-volatile matrix compounds. The method can be applied to all classes of cosmetic samples, including water containing matrices such as shower gels or body creams. In combination with selectable (1)D/(2)D GC-MS, consisting of a dedicated heart-cutting GC-MS configuration using capillary flow technology (CFT) and low thermal mass GC (LTM-GC), a highly flexible and easy-to-use analytical solution is offered. Depending on the complexity of the perfume fraction, analyses can be performed in one-dimensional GC-MS mode or in heart-cutting two-dimensional GC-MS mode, without the need of hardware reconfiguration. The two-dimensional mode with independent temperature control of the first and second dimension column is especially useful to confirm the presence of detected allergen compounds when mass spectral deconvolution is not possible. PMID:22342208

Devos, Christophe; Ochiai, Nobuo; Sasamoto, Kikuo; Sandra, Pat; David, Frank

2012-02-03

195

[Method for study of phase transitions in evaporating drop and its application for evaluation of physical-chemical properties of water and water solutions].  

PubMed

Spatial-temporal crystallization features of inorganic chlorides in evaporating drops of water solutions, considering solid surface wettability, were studied using a microscopic technique and the acoustical impedansometry. Physical-chemical mechanisms responsible for the difference in "dynamical portraits" of distilled water and salt solutions, as well as relaxation effects in water were discussed. The study demonstrated the potential use of a drying drop method in registration of changes in water properties under the action of physical and chemical factors. PMID:23272573

Iakhno, T A; Sanin, A G; Sanina, O A; Iakhno, V G

196

Cosolvent Evaporation Method for Enhancement of Solubility and Dissolution Rate of Poorly Aqueous Soluble Drug Simvastatin: In vitro – In vivo Evaluation  

Microsoft Academic Search

A number of synthesized chemical molecules suffer from low aqueous solubility problems. Enhancement of aqueous solubility,\\u000a dissolution rate, and bioavailability of drug is a very challenging task in drug development. In the present study, solubility\\u000a and dissolution of poorly aqueous soluble drug simvastatin (SIM) was enhanced using hydrophilic, low viscosity grade polymer\\u000a hydroxypropyl methylcellulose (HPMC K3LV). The co-solvent evaporation method

Priyanka Pandya; Surendra Gattani; Pankaj Jain; Lokesh Khirwal; Sanjay Surana

2008-01-01

197

Influence of process parameters on the size distribution of PLA microcapsules prepared by combining membrane emulsification technique and double emulsion-solvent evaporation method  

Microsoft Academic Search

Relatively uniform-sized biodegradable poly(lactide) (PLA) microcapsules with various sizes were successfully prepared by combining a glass membrane emulsification technique and water-in-oil-in-water (w1\\/o\\/w2) double emulsion-solvent evaporation method. A water phase was used as the internal water phase, a mixture solvent of dichloromethane (DCM) and toluene dissolving PLA and Arlacel 83 was used as the oil phase (o). These two solutions were

Rong Liu; Guang-Hui Ma; Yin-Hua Wan; Zhi-Guo Su

2005-01-01

198

DWPF RECYCLE EVAPORATOR FLOWSHEET EVALUATION (U)  

SciTech Connect

The Defense Waste Processing Facility (DWPF) converts the high level waste slurries stored at the Savannah River Site into borosilicate glass for long-term storage. The vitrification process results in the generation of approximately five gallons of dilute recycle streams for each gallon of waste slurry vitrified. This dilute recycle stream is currently transferred to the H-area Tank Farm and amounts to approximately 1,400,000 gallons of effluent per year. Process changes to incorporate salt waste could increase the amount of effluent to approximately 2,900,000 gallons per year. The recycle consists of two major streams and four smaller streams. The first major recycle stream is condensate from the Chemical Process Cell (CPC), and is collected in the Slurry Mix Evaporator Condensate Tank (SMECT). The second major recycle stream is the melter offgas which is collected in the Off Gas Condensate Tank (OGCT). The four smaller streams are the sample flushes, sump flushes, decon solution, and High Efficiency Mist Eliminator (HEME) dissolution solution. These streams are collected in the Decontamination Waste Treatment Tank (DWTT) or the Recycle Collection Tank (RCT). All recycle streams are currently combined in the RCT and treated with sodium nitrite and sodium hydroxide prior to transfer to the tank farm. Tank Farm space limitations and previous outages in the 2H Evaporator system due to deposition of sodium alumino-silicates have led to evaluation of alternative methods of dealing with the DWPF recycle. One option identified for processing the recycle was a dedicated evaporator to concentrate the recycle stream to allow the solids to be recycled to the DWPF Sludge Receipt and Adjustment Tank (SRAT) and the condensate from this evaporation process to be sent and treated in the Effluent Treatment Plant (ETP). In order to meet process objectives, the recycle stream must be concentrated to 1/30th of the feed volume during the evaporation process. The concentrated stream must be pumpable to the DWPF SRAT vessel and should not precipitate solids to avoid fouling the evaporator vessel and heat transfer coils. The evaporation process must not generate excessive foam and must have a high Decontamination Factor (DF) for many species in the evaporator feed to allow the condensate to be transferred to the ETP. An initial scoping study was completed in 2001 to evaluate the feasibility of the evaporator which concluded that the concentration objectives could be met. This initial study was based on initial estimates of recycle concentration and was based solely on OLI modeling of the evaporation process. The Savannah River National Laboratory (SRNL) has completed additional studies using simulated recycle streams and OLI{reg_sign} simulations. Based on this work, the proposed flowsheet for the recycle evaporator was evaluated for feasibility, evaporator design considerations, and impact on the DWPF process. This work was in accordance with guidance from DWPF-E and was performed in accordance with the Technical Task and Quality Assurance Plan.

Stone, M

2005-04-30

199

Sewage Disposal by Evaporation-Transpiration.  

National Technical Information Service (NTIS)

One of the methods for on-site disposal of wastewater from individual homes is by evaporation. Two types of evaporative disposal systems have been investigated in this study; evapo-transpiration (ET) beds and mechanical evaporation units. Twenty nine test...

E. R. Bennett K. D. Linstedt

1978-01-01

200

SEWAGE DISPOSAL BY EVAPORATION-TRANSPIRATION  

EPA Science Inventory

One of the methods for on-site disposal of wastewater from individual homes is by evaporation. Two types of evaporative disposal systems have been investigated in this study; evapo-transpiration (ET) beds and mechanical evaporation units. Twenty nine test lysimeters of 0.22 cubic...

201

Laboratory Prototype Flash Evaporator.  

National Technical Information Service (NTIS)

A laboratory prototype flash evaporator that is being developed as a candidate for the space shuttle environmental control system expendable heat sink is described. The single evaporator configuration uses water as an evaporant to accommodate reentry and ...

J. L. Gaddis

1972-01-01

202

Low NOx gas burner apparatus and methods  

Microsoft Academic Search

An improved gas burner apparatus is described for discharging a mixture of fuel gas and air into a furnace space wherein said mixture is burned and flue gases having low NO[sub x] content are formed therefrom comprising: a housing having an open end attached to said furnace space; means for introducing a controlled flow rate of said air into said

R. E. Schwartz; S. O. Napier; A. P. Jones

1993-01-01

203

Preparation and properties of transparent conducting zinc oxide and aluminium-doped zinc oxide films prepared by evaporating method  

Microsoft Academic Search

Undoped and aluminium-doped zinc oxide films have been prepared by thermal evaporation of zinc acetate [Zn(CH3COO)2 2H2O] and aluminium chloride [AlCl3] onto a heated glass substrate. The structural and optoelectrical properties of the films have been studied. The effects of heat treatment for the as-deposited films in air and vaccum are investigated. Highly transparent films with conductivity as low as

Jin Ma; Feng Ji; Hong-lei Ma; Shu-ying Li

2000-01-01

204

Fabrication of amorphous ni- si films with small temperature coefficient of resistance by new flash evaporating method  

Microsoft Academic Search

Utilizing a heat treatment processes, Ni-Si thin films which have various resistivity and various and\\/or small temperature\\u000a coefficients of resistance (TCR) can be fabricated by new flash evaporating equipment assembled in our laboratory. In relation\\u000a to the increase of Si content in the film, the TCR of the as-deposited film increases negatively. By using heat treatment\\u000a to stabilize it, the

Jun-Ichi Kodama

1995-01-01

205

Method for testing and monitoring for producing landfill gas  

Microsoft Academic Search

A method of withdrawing landfill gas from a landfill without drawing air into the landfill comprises providing a well in the landfill and withdrawing landfill gas from the well at a plurality of different withdrawal rates. The pressure at a selected region within the landfill is detected while the landfill gas is being withdrawn. A relationship is then established between

R. D. Johnson; R. S. Altmann

1977-01-01

206

Prevention against Oxidation of Mn Evaporant during Reactive Evaporation Process  

NASA Astrophysics Data System (ADS)

Manganese oxide films for lithium secondary batteries were prepared using a reactive evaporation method. The Mn metal in the crucible suffers severe oxidation during the reactive evaporation process, during which its deposition rate deteriorates with increasing deposition run. So it is difficult to maintain the stoichiometry of films from run to run. To prevent deteriorations, a quartz ampoule has been installed at the bottom of the Mn crucible, which isolated successfully the Mn evaporant from incoming oxygen atoms. It improved the reproducibility of film composition because of stabilizing of the deposition rate. The performance of quartz ampoule was compared with that of Mo separator and stainless steel (SUS) cell.

Isai, Masaaki; Fujiyasu, Hiroshi

2001-11-01

207

Gas Levitator and Method for Containerless Processing.  

National Technical Information Service (NTIS)

An elongated levitation tube having a contoured interior in the form of a convergent section, and a constriction and divergent section, wherein the levitation node is created, is described. Gas flow control means control flow to prevent separation of flow...

L. H. Berge W. A. Oran J. M. Theiss

1981-01-01

208

System and method for efficiently generating power in a solid fuel gas turbine  

Microsoft Academic Search

This patent describes a method for generating electrical power utilizing a compressor, spray evaporator, turbine, pressurized fluidized bed combustor (hereinafter PFBC), regenerator, dynamo-electric machine, and solid fuel. It comprises: compressing and heating air in the compressor; cooling the hot compressed air in the spray evaporator, thereby producing cooled compressed air of increased mass flow; heating the cooled compressed air in

1991-01-01

209

Flue gas desulfurization method and apparatus  

DOEpatents

A combined furnace limestone injection and dry scrubber flue gas desulfurization (FGD) system collects solids from the flue gas stream in first particulate collection device located downstream of an outlet of a convection pass of the furnace and upstream of the dry scrubber. The collected solids are diverted to the dry scrubber feed slurry preparation system to increase sulfur oxide species removal efficiency and sorbent utilization. The level of lime in the feed slurry provided to the dry scrubber is thus increased, which enhances removal of sulfur oxide species in the dry scrubber. The decreased particulate loading to the dry scrubber helps maintain a desired degree of free moisture in the flue gas stream entering the dry scrubber, which enhances sulfur oxide species removal both in the dry scrubber and downstream particulate collector, normally a baghouse.

Madden, Deborah A. (Canfield, OH); Farthing, George A. (Washington Township, Stark County, OH)

1998-08-18

210

Method of immobilizing carbon dioxide from gas streams  

Microsoft Academic Search

This invention is a method for rapidly and continuously immobilizing carbon dioxide contained in various industrial off-gas streams, the carbon dioxide being immobilized as dry, stable, and substantially water-insoluble particulates. Briefly, the method comprises passing the gas stream through a fixed or fluidized bed of hydrated barium hydroxide to remove and immobilize the carbon dioxide by converting the bed to

David W. Holladay; Gary L. Haag

1979-01-01

211

Method of immobilizing carbon dioxide from gas streams  

Microsoft Academic Search

This invention comprises a method for rapidly and continuously immobilizing carbon dioxide contained in various industrial off-gas streams, the carbon dioxide being immobilized as dry, stable, and substantially water-insoluble particulates. Briefly, the method comprises passing the gas stream through a fixed or fluidized bed of hydrated barium hydroxide to remove and immobilize the carbon dioxide by converting the bed to

D. W. Holladay; G. L. Haag

1979-01-01

212

Method for producing natural gas from a coal seam  

SciTech Connect

A method is described of producing natural gas from a coal seam, comprising: (a) producing natural gas and liquid from a coal seam through at least one well; (b) ceasing the production of natural gas and liquid from the coal seam and injecting natural gas into the coal seam through at least one well at a pressure higher than coal seam pressure but lower than fracture pressures of immediately adjacent formations above or below the coal seam; and (c) subsequently producing natural gas and liquid from the coal seam through at least one well.

Puri, R.; Yee, D.; Seidle, J.P.

1988-07-12

213

Formation of Quasicrystalline Aluminium-Vanadium and Aluminium-Chromium Fine Particles by Gas-Evaporation Technique  

NASA Astrophysics Data System (ADS)

Fine particles in icosahedral phase have been prepared by the gasevaporation method, and studied by electron microscopy. The particles are spherical ranging from 20 to 300 nm in diameter and show a characteristic contrast with an irregular striation. Edge lengths of the fundamental hexahedron in the Penrose tiling are 0.474± 0.002 nm in the Al-V system and 0.473± 0.003 nm in the Al-Cr system. Though most of the quasicrystalline particles are in a single phase, composite particles of the icosahedral phase and the crystalline phase(?-Al6V) are also observed in the Al-V system. From the orientation relationship between the two phases, atomic sites of vanadium in the icosahedral phase are discussed.

Okazaki, Tsugio; Maki, Takasi; Saito, Yahachi; Mihama, Kazuhiro

1989-02-01

214

Comparison of spray freeze drying and the solvent evaporation method for preparing solid dispersions of baicalein with Pluronic F68 to improve dissolution and oral bioavailability.  

PubMed

The objective of this study was to prepare solid dispersions consisting of baicalein and a carrier with a low glass transition/melting point (Pluronic F68) by spray freeze drying (SFD). We compared these powders to those produced from the conventional solvent evaporation method. In the SFD process, a feeding solution was atomized above the surface of liquid nitrogen following lyophilization, which resulted in instantaneously frozen microparticles. However, solid dispersions prepared by the solvent evaporation method formed a sticky layer on the glass flask with crystalline baicalein separated out from the carrier. The powder samples were characterized by scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), surface area measurement, differential scanning calorimetry, and Fourier transform infrared spectrometry. SEM and PXRD results suggested that the majority of baicalein in the SFD-processed solid dispersion was in the amorphous state, which has a higher specific surface area than pure baicalein. However, the majority of baicalein was recrystallized in the solid dispersion at the same composition prepared by the solvent evaporation method, which showed a similar dissolution rate to the physical mixture. SFD product was physically and chemically stable after being stored at 40 °C with low humidity for 6 months. After enzyme hydrolysis, baicalein in the SFD product displayed a significantly shorter T (max) and higher C (max) than pure baicalein after oral dosing. The relative bioavailability of the SFD product versus pure baicalein determined by comparing the AUC(0-12) was 233%, which demonstrated the significantly improved oral bioavailability of baicalein produced by the SFD technique. PMID:21181514

He, Xiuqiong; Pei, Lixia; Tong, Henry H Y; Zheng, Ying

2010-12-23

215

Modern methods rediscover deep gas. [Texas  

Microsoft Academic Search

In 1973, Northern Natural Gas (NNG) Co.'s Midland exploration and production district acquired a 7-section lease block on a Devonian-Montoya prospect suggested by trend geology and limited seismic data. This acreage block was 2 miles west of the abandoned Hershey field, and included acreage on which the Devonian was tested at noncommercial rates in 1962. Additional seismic data confirmed the

1979-01-01

216

Method and apparatus for recovering a gas from a gas hydrate located on the ocean floor  

DOEpatents

A method and apparatus for recovering a gas from a gas hydrate on the ocean floor includes a flexible cover, a plurality of steerable base members secured to the cover, and a steerable mining module. A suitable source for inflating the cover over the gas hydrate deposit is provided. The mining module, positioned on the gas hydrate deposit, is preferably connected to the cover by a control cable. A gas retrieval conduit or hose extends upwardly from the cover to be connected to a support ship on the ocean surface.

Wyatt, Douglas E. (Aiken, SC)

2001-01-01

217

Method and apparatus for off-gas composition sensing  

Microsoft Academic Search

An apparatus and method for non-intrusive collection of off-gas data in a steelmaking furnace includes structure and steps for transmitting a laser beam through the off-gas produced by a steelmaking furnace, for controlling the transmitting to repeatedly scan the laser beam through a plurality of wavelengths in its tuning range, and for detecting the laser beam transmitted through the off-gas

David Keith Ottesen; Sarah Williams Allendorf; Gary Lee Hubbard; David Ezechiel Rosenberg

1999-01-01

218

Effects of gold catalysts and thermal evaporation method modifications on the growth process of Zn{sub 1-x}Mg{sub x}O nanowires  

SciTech Connect

In this paper, we investigate the roles of gold catalysts and thermal evaporation method modifications in the growth process of Zn{sub 1-x}Mg{sub x}O nanowires. Zn{sub 1-x}Mg{sub x}O nanowires are fabricated on silicon substrates with and without using a gold catalyst. Characterizations reveal that Mg acts in a self-catalyst role during the growth process of Zn{sub 1-x}Mg{sub x}O nanowires grown on catalyst-free substrate. The optical properties and crystalline quality of the Zn{sub 1-x}Mg{sub x}O nanowires are characterized by room temperature photoluminescence (PL) measurements and Raman spectroscopy, respectively. The Raman and PL studies demonstrate that the Zn{sub 1-x}Mg{sub x}O nanowires grown using the catalyst-free method have good crystallinity with excellent optical properties and have a larger band-gap in comparison to those grown with the assistance of gold. - Graphical abstract: ZnMgO nanowires can be formed with and without gold catalyst by a modified thermal evaporation method.

Yousefi, Ramin, E-mail: yousefi.ramin@gmail.co [Solid State Laboratory, Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Department of Physics, Islamic Azad University, Masjed-Soleiman Branch, Masjed-Soleiman (Iran, Islamic Republic of); Muhamad, Muhamad Rasat [Solid State Laboratory, Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia)

2010-07-15

219

Impact of Pore Size and Salt Precipitation on the Evaporation From Porous Media  

NASA Astrophysics Data System (ADS)

Evaporation is a major process in the global water cycle. The literature on micro-scale evaporation mechanisms and the influence of the resulted salt precipitation within pores on evaporation processes is limited. Moreover, the role of heterogeneity on the combined evaporation - salt precipitation processes is poorly understood. This research focuses on salt deposition inside the matrix pores during the evaporation process and its correlation to gas permeability of the matrix. Another goal is to explore the combined impact of salt precipitation and heterogeneities on evaporation. Two experimental methods are used: (1) quantifying salt deposition in pores with high-resolution X-ray CT; and (2) monitoring of evaporation and salt deposition in controlled columns. In the first experiment, a Berea Sandstone, saturated with five percent NaI solution was allowed to evaporated naturally for five days while the water, air, and salt distributions were monitored periodically using X-ray CT. Klinkenberg permeabilities were determined prior to and following the evaporation process to explore the impact of salt deposition within the matrix on gas permeability. In the second experiment, eight columns were packed with fine and coarse sand as well as fine and coarse sand combined, with a textural interface between the two grain sizes. Four columns were saturated with DI water and the rest with salty solution. The columns were placed in a temperature controlled room with continuous monitoring of evaporation rates. Fifty percent of the salt precipitated at the top seven mm of the sandstone sample, near the evaporating interface. Large pores (>200 micron) remained open with very small amount of precipitated salt crystals, while the smaller pores were mostly clogged with salt. These observations indicate that the solution migrated to the evaporation surface by capillarity. The gas permeability was reduced by ten percent supporting the observation that most of the large-pores remained open. Preliminary results from the column experiments indicate that both grain size and pore-water salinity play a major role in the evaporation rate.

Nachshon, U.; Grader, A.; Weisbrod, N.; Dragila, M. I.

2007-12-01

220

Apparatus and method for excluding gas from a liquid  

DOEpatents

The present invention is directed to an apparatus and method for preventing diffusion of a gas under high pressure into the bulk of a liquid filling a substantially closed chamber. This apparatus and method is particularly useful in connection with test devices for testing fluid characteristics under harsh conditions of extremely high pressure and high temperature. These devices typically pressurize the liquid by placing the liquid in pressure and fluid communication with a high pressure inert gas. The apparatus and method of the present invention prevent diffusion of the pressurizing gas into the bulk of the test liquid by decreasing the chamber volume at a rate sufficient to maintain the bulk of the liquid free of absorbed or dissolved gas by expelling that portion of the liquid which is contaminated by the pressurizing gas.

Murphy, Jr., Robert J. (Bellaire, TX)

1985-01-01

221

A steady-state non-equilibrium molecular dynamics approach for the study of evaporation processes  

NASA Astrophysics Data System (ADS)

Two non-equilibrium methods (called bubble method and splitting method, respectively) have been developed and tested to study the steady state evaporation of a droplet surrounded by its vapor, where the evaporation continuously occurs at the vapor-liquid interface while the droplet size remains constant. In the bubble method, gas molecules are continuously reinserted into a free volume (represented by a bubble) located at the centre of mass of the droplet to keep the droplet size constant. In the splitting method, a molecule close to the centre of mass of the droplet is split into two: In this way, the droplet size is also maintained during the evaporation. By additional local thermostats confined to the area of insertion, the effect of frequent insertions on properties such as density and temperature can be limited to the immediate insertion area. Perturbations are not observed in other parts of the droplet. In the end, both the bubble method and the splitting method achieve steady-state droplet evaporation. Although these methods have been developed using an isolated droplet, we anticipate that they will find a wide range of applications in the study of the evaporation of isolated films and droplets or thin films on heated substrates or under confinement. They can in principle also be used to study the steady-state of other physical processes, such as the diffusion or permeation of gas molecules or ions in a pressure gradient or a concentration gradient.

Zhang, Jianguo; Müller-Plathe, Florian; Yahia-Ouahmed, Méziane; Leroy, Frédéric

2013-10-01

222

Method for scrubbing pollutants from an exhaust gas stream  

Microsoft Academic Search

This patent describes a method of treatment of an exhaust gas stream containing as pollutants at least one of the acidic oxides of sulfur, nitrogen, carbon, and halogens and acidic halogen compounds, whose temperature exceeds the dew point of the gas, for producing scrubbed exhaust and useful or benign by-products. It comprises: providing a basic aqueous slurry of ash, the

1992-01-01

223

Method and Apparatus for Measuring Gas Flow Speed.  

National Technical Information Service (NTIS)

A method and apparatus for measuring the speed of a gas stream, particularly suitable for use in detecting wind speed, uses the gas flow to create a negative pressure across a pressure sampling port oriented with its axis substantially perpendicular to th...

T. T. Fujita A. J. Bedard

1978-01-01

224

Selected methods of reflux-hydrocarbon gas separation process  

Microsoft Academic Search

A process is described for the recovery of components of volatile gas containing methane and heavier components wherein one of three specific methods of reflux is used the selection being dependent upon the specific requirements of rectification, in each instance the process consisting of introducing a primary stream of feed gas under pressure into a heat exchange unit to lower

Cook

1986-01-01

225

Method and apparatus for recovery of combustible gas from waste  

Microsoft Academic Search

A method and apparatus is disclosed for recovery of combustible gas formed from combustible refuse or vegetable matter in an enclosed space from which the combustible gas is collected. Water can be injected into the apparatus and the decay process initiated and promoted by activating a heating element projecting upwardly from the base of the apparatus into the material undergoing

Ricks

1980-01-01

226

Characterization of 5-fluorouracil loaded liposomes prepared by reverse-phase evaporation or freezing-thawing extrusion methods: study of drug release.  

PubMed

Entrapment of the anti-tumoral drug 5-fluorouracil (5-FU) in unilamellar liposomes prepared by freeze-thawing extrusion technique (FATVET) and the reverse-phase evaporation method (REV) from natural (bovine brain) sphingomyelin (SM) and synthetic distearoylphosphatidylcholine (DSPC) phospholipids was studied. Reverse-phase evaporation vesicles obtained from DSPC sized through polycarbonate membranes of 0.2 micron pore size were found to entrap roughly double amounts of drug than did extruded liposomes (0.1 micron pore size); however, s-REV in these preparations were more heterogenous in vesicle size than FATVET. The rate of in vitro drug release from the liposomes was found to be dependent of the bilayer composition and the method used to prepare the vesicles. The permeability coefficient P obtained was approx. 10(-11) m/s. The results suggest that 5-FU release is kinetically controlled by an interfacial process seemingly dependent on the surface activity of the drug. Also, the physical state of the bilayer determines the retention capacity of the vesicles. Thus, liposomes consisting of distearoylphosphatidylcholine whose acyl chains were in a gel state at the working temperature (37 degrees C) retained 70% of encapsulated 5-FU after 1 h, whereas liposomes composed of natural bovine brain sphingomyelin retained only 15% over the same period. PMID:8274483

Elorza, B; Elorza, M A; Frutos, G; Chantres, J R

1993-12-12

227

Reservoir evaporation in central Colorado  

USGS Publications Warehouse

Evaporation losses from seven reservoirs operated by the Denver Water Department in central Colorado were determined during various periods from 1974 to 1980. The reservoirs studies were Ralston, Cheesman, Antero, Williams Fork, Elevenmile Canyon, Dillon, and Gross. Energy-budget and mass-transfer methods were used to determine evaporation. Class-A pan data also were collected at each reservoir. The energy-budget method was the most accurate of the methods used to determine evaporation. At Ralston, Cheesman, Antero, and Williams Fork Reservoirs the energy-budget method was used to calibrate the mass-transfer coefficients. Calibrated coefficients already were available for Elevenmile Canyon, Dillon, and Gross Reservoirs. Using the calibrated coefficients, long-term mass-transfer evaporation rates were determined. Annual evaporation values were not determined because the instrumentation was not operated for the entire open-water season. Class-A pan data were used to determine pan coefficients for each season at each reservoir. The coefficients varied from season to season and between reservoirs, and the seasonal values ranged from 0.29 to 1.05. (USGS)

Spahr, N. E.; Ruddy, B. C.

1983-01-01

228

Method for making hydrogen rich gas from hydrocarbon fuel  

DOEpatents

A method of forming a hydrogen rich gas from a source of hydrocarbon fuel in which the hydrocarbon fuel contacts a two-part catalyst comprising a dehydrogenation portion and an oxide-ion conducting portion at a temperature not less than about 400 C for a time sufficient to generate the hydrogen rich gas while maintaining CO content less than about 5 volume percent. There is also disclosed a method of forming partially oxidized hydrocarbons from ethanes in which ethane gas contacts a two-part catalyst comprising a dehydrogenation portion and an oxide-ion conducting portion for a time and at a temperature sufficient to form an oxide. 4 figs.

Krumpelt, M.; Ahmed, S.; Kumar, R.; Doshi, R.

1999-07-27

229

Method for making hydrogen rich gas from hydrocarbon fuel  

DOEpatents

A method of forming a hydrogen rich gas from a source of hydrocarbon fuel in which the hydrocarbon fuel contacts a two-part catalyst comprising a dehydrogenation portion and an oxide-ion conducting portion at a temperature not less than about 400.degree. C. for a time sufficient to generate the hydrogen rich gas while maintaining CO content less than about 5 volume percent. There is also disclosed a method of forming partially oxidized hydrocarbons from ethanes in which ethane gas contacts a two-part catalyst comprising a dehydrogenation portion and an oxide-ion conducting portion for a time and at a temperature sufficient to form an oxide.

Krumpelt, Michael (Naperville, IL); Ahmed, Shabbir (Bolingbrook, IL); Kumar, Romesh (Naperville, IL); Doshi, Rajiv (Downers Grove, IL)

1999-01-01

230

Evaporator Cleaning Studies  

SciTech Connect

Operation of the 242-16H High Level Waste Evaporator proves crucial to liquid waste management in the H-Area Tank Farm. Recent operational history of the Evaporator showed significant solid formation in secondary lines and in the evaporator pot. Additional samples remain necessary to ensure material identity in the evaporator pot. Analysis of these future samples will provide actinide partitioning information and dissolution characteristics of the solid material from the pot to ensure safe chemical cleaning.

Wilmarth, W.R.

1999-04-15

231

Evaporative cooling in insects  

Microsoft Academic Search

Insects commonly use behavior to avoid the heat stress and consequent water loss of hot environments. It has been assumed by many to be impossible or impractical for insects to employ evaporative cooling. Despite this assumption, there have been many instances, historically and recently where insects are reported to survive otherwise lethal temperatures by evaporating water. The site of evaporation

Henry D. Prange

1996-01-01

232

Lubricant Vapor Pressure Derived from Evaporation Loss  

Microsoft Academic Search

A method is presented for obtaining vapor pressures over the temperature range of interest in engine lubrication (300–500 F). The determination is based on the saturation efficiency of an air stream and the relationship between vapor pressure and evaporation loss. All data required are readily obtained from the ASTM Evaporation Test Method D 972-56 which is already used in connection

John F. Coburn

1969-01-01

233

Method of preparing pure fluorine gas  

DOEpatents

A simple, inexpensive system for purifying and storing pure fluorine is described. The method utilizes alkali metal-nickel fluorides to absorb tank fluorine by forming nickel complex salts and leaving the gaseous impurities which are pumped away. The complex nickel fluoride is then heated to evolve back pure gaseous fluorine.

Asprey, Larned B. (Los Alamos, NM)

1976-01-01

234

Method of gas purification and system therefor  

DOEpatents

A method and device are disclosed for conducting gettering. The gettering is conducted with one of an LiB, LiSi or LiAl system. Preferably the LiB system is of the formula Li/sub x/B/sub 1-x/ wherein 0 < x < 1 with gettering conducted at room or slightly elevated temperature of about 100 to 200/sup 0/C.

Szwarc, R.

1983-12-29

235

Method of gas purification and system therefor  

DOEpatents

A method and device for conducting gettering. The gettering is conducted with one of an LiB, LiSi or LiAl system. Preferably the LiB system is of the formula Li.sub.x B.sub.1-x wherein 0

Szwarc, Raphael (Largo, FL)

1985-04-23

236

Method predicts hydrates for high-pressure gas streams  

SciTech Connect

A new procedure extends the pressure range for estimating hydrate formation in high-pressure gas wells such as those now being developed in the North Sea. The method applies for uninhibited as well as methanol and ethylene glycol inhibited hydrate-forming conditions of pure components and natural gas mixtures. Accurate information concerning the conditions under which hydrates will form or exist in a natural gas stream are vital to the natural gas industry. As pressure-temperature conditions used for transporting natural gas become more severe, predicting hydrate forming conditions becomes increasingly difficult. Addition of a hydrate inhibitor, such as methanol or ethylene glycol, further complicates reliable prediction of hydrate-forming conditions. The paper describes hydrate formation, model development, and model validation.

Moshfeghian, M. (Bushier Univ. (Iran, Islamic Republic of)); Maddox, R.N. (Maddox (R.N.), Stillwater, OK (United States))

1993-08-30

237

Asymptotic behavior of rotating rarefied gases with evaporation and condensation  

Microsoft Academic Search

The asymptotic behavior of the cylindrical Couette flow problem for a rarefied rotating gas with evaporation and condensation is studied when the state of equilibrium is perturbed by the following small thermodynamic forces: (i) the pressure difference of the evaporating gas; (ii) the angular velocity difference of the cylinders; and (iii) the temperature difference of the cylinders. The problem is

Liliana M. G. Cumin; Gilberto M. Kremer; Felix Sharipov

2001-01-01

238

Rain scavenging of soluble gases by non-evaporating and evaporating droplets from inhomogeneous atmosphere  

NASA Astrophysics Data System (ADS)

We suggest a one-dimensional model of precipitation scavenging of soluble gaseous pollutants by non-evaporating and evaporating droplets that is valid for arbitrary initial vertical distribution of soluble trace gases in the atmosphere. It is shown that for low gradients of soluble trace gases in the atmosphere, scavenging of gaseous pollutants is governed by a linear wave equation that describes propagation of a wave in one direction. The derived equation is solved by the method of characteristics. Scavenging coefficient and the rates of precipitation scavenging are calculated for wet removal of sulfur dioxide (SO2) and ammonia (NH3) using measured initial distributions of trace gases. It is shown that scavenging coefficient for arbitrary initial vertical distribution of soluble trace gases in the atmosphere is non-stationary and height-dependent. In case of exponential initial distribution of soluble trace gases in the atmosphere, scavenging coefficient for non-evaporating droplets in the region between the ground and the position of a scavenging front is a product of rainfall rate, solubility parameter, and the growth constant in the formula for the initial profile of a soluble trace gas in the atmosphere. This expression yields the same estimate of scavenging coefficient for sulfur dioxide scavenging by rain as field estimates presented in McMahon and Denison (1979). It is demonstrated that the smaller the slope of the concentration profile the higher the value of a scavenging coefficient.

Elperin, Tov; Fominykh, Andrew; Krasovitov, Boris

2013-10-01

239

Evaporation rate of nucleating clusters.  

PubMed

The Becker-Döring kinetic scheme is the most frequently used approach to vapor liquid nucleation. In the present study it has been extended so that master equations for all cluster configurations are included into consideration. In the Becker-Döring kinetic scheme the nucleation rate is calculated through comparison of the balanced steady state and unbalanced steady state solutions of the set of kinetic equations. It is usually assumed that the balanced steady state produces equilibrium cluster distribution, and the evaporation rates are identical in the balanced and unbalanced steady state cases. In the present study we have shown that the evaporation rates are not identical in the equilibrium and unbalanced steady state cases. The evaporation rate depends on the number of clusters at the limit of the cluster definition. We have shown that the ratio of the number of n-clusters at the limit of the cluster definition to the total number of n-clusters is different in equilibrium and unbalanced steady state cases. This causes difference in evaporation rates for these cases and results in a correction factor to the nucleation rate. According to rough estimation it is 10(-1) by the order of magnitude and can be lower if carrier gas effectively equilibrates the clusters. The developed approach allows one to refine the correction factor with Monte Carlo and molecular dynamic simulations. PMID:22112089

Zapadinsky, Evgeni

2011-11-21

240

Rate of runaway evaporative cooling  

SciTech Connect

Evaporative cooling is a process that is essential in creating Bose-Einstein condensates in dilute atomic gasses. This process has often been simulated based on a model using a truncated Boltzmann distribution. This model assumes that the energy distribution up to the threshold energy can still be described by a Boltzmann distribution: it assumes detailed balance up to the threshold energy. However, the evolution of the distribution function in time is not taken into account. Here we solve the kinetic Boltzmann equation for a gas undergoing evaporative cooling in a harmonic and linear trap in order to determine the evolution of the energy distribution. The magnitude of the discrepancy with the truncated Boltzmannmodel is calculated by including a polynomial expansion of the distribution function. We find that up to 35% fewer particles are found in the high-energy tail of the distribution with respect to the truncated Boltzmann distribution and up to 15% more collisions are needed to reach quantum degeneracy. Supported by a detailed investigation of the particle loss rate at different energies, we conclude that the limited occupation of high-energy states during the evaporation process causes the lowering of the evaporation speed and efficiency.

Groep, J. van de; Straten, P. van der; Vogels, J. M. [Atom Optics and Ultrafast Dynamics, Utrecht University, P.O. Box 80, 000, NL-3508 TA Utrecht (Netherlands)

2011-09-15

241

Evaporative cooling of air in impinging streams  

Microsoft Academic Search

An experimental study was conducted on evaporative cooling of air in an impinging-stream reactor, in which two droplet gas streams flow in opposite directions and meet in the impingement zone. The air was cooled by evaporation of water droplets. Volumetric heat-transfer coefficients h{sub v} determined enabled the authors to evaluate the performance of the cooler. Maximum values of h{sub v}

B. Yao; Y. Berman; A. Tamir

1995-01-01

242

Analysis of evaporation in laser welding  

Microsoft Academic Search

The evaporation process in CO2 laser welding was analyzed experimentally on the basis of evaporation and soot deposition rates, light scattering and plasma behavior. Heavier shielding gas results in more soot deposition by carrying the condensed particles to the work surface. At power density, 2-3 x 10(exp 5) W\\/sq cm), which is just below the critical value for deep penetration

Isamu Miyamoto

1995-01-01

243

Direct analysis of artemisinin from Artemisia annua L. using high-performance liquid chromatography with evaporative light scattering detector, and gas chromatography with flame ionization detector  

Microsoft Academic Search

Since the isolation of artemisinin 32 years ago, it has been analyzed by different chromatographic techniques. This work compared the analysis of artemisinin from crude plant samples by GC with flame ionization detection (GC–FID) and HPLC with evaporative light scattering detector (HPLC–ELSD). Data is also presented indicating that GC is suitable for the quantification of two of artemisinin precursors (arteannuin

Congyue A. Peng; Jorge F. S. Ferreira; Andrew J. Wood

2006-01-01

244

A new gas dilution method for measuring body volume.  

PubMed Central

This study was designed to examine the validity of a new gas dilution method (GD) for measuring human body volume and to compare its accuracy with the results obtained by the underwater weighing method (UW). We measured the volume of plastic bottles and 16 subjects (including two females), aged 18-42 years with each method. For the bottles, the volume measured by hydrostatic weighing was correlated highly (r = 1.000) with that measured by the new gas dilution method. For the subjects, the body volume determined by the two methods was significantly correlated (r = 0.998). However, the subject's volume measured by the gas dilution method was significantly larger than that by underwater weighing method. There was significant correlation (r = 0.806) between GD volume-UW volume and the body mass index (BMI), so that UW volume could be predicted from GD volume and BMI. It can be concluded that the new gas dilution method offers promising possibilities for future research in the population who cannot submerge underwater.

Nagao, N; Tamaki, K; Kuchiki, T; Nagao, M

1995-01-01

245

Information preservation methods for modeling micro-scale gas flows  

NASA Astrophysics Data System (ADS)

Micro-scale gas flow is a rapidly growing research field driven by microsystems technology. Experiments have shown that fluid mechanics of these flows are not the same as those experienced in the macroscopic world. However, theoretical analysis is difficult because those flows are generally in the slip or transitional flow regime, and it is hard to investigate the detailed flow fields experimentally due to the small physical dimensions of microsystems. There are several numerical approaches that can model some micro-scale gas flows. Generally, continuum-based methods are numerically efficient, but physically limited; kinetic-based methods are physically accurate, but numerically expensive. Hence, it is necessary to develop a general-purpose numerical approach to understand micro-scale gas flows. This dissertation is devoted to developing a numerical approach for modeling general micro-scale gas flows with reasonable efficiency and accuracy. In the first stage, a particle method called the information preservation (IP) method, proposed by Fan and Shen based on the direct simulation Monte Carlo (DSMC) method, is developed to simulate general micro-scale gas flows. The IP method greatly reduces the statistical scatter associated with particle methods by using macroscopic information preserved in microscopic particles to sample the flow field. Thus low-speed micro-scale gas flows can be simulated using the IP method with reasonable numerical cost. In the second stage, a hybrid approach is designed by coupling the IP method and a Navier-Stokes solver for modeling micro-scale gas flows with better numerical efficiency. The IP method and the Navier-Stokes solver are strongly coupled using an adaptive continuum/particle interface. Using the hybrid approach, we investigate gas flows over micro-scale flat plates. We find that the normalized drag coefficient CDM on a flat plate having zero thickness depends on Re/M0.8 when 1

Sun, Quanhua

246

Gas-kinetic moving mesh methods for viscous flow simulations  

NASA Astrophysics Data System (ADS)

In this thesis, the gas-kinetic BGK scheme for two-dimensional viscous flow computation is extended to the moving meshes. Specifically, both the static adaptive grid method and dynamic unified moving mesh method have been developed. In the former one, the grid movement and adaptation are controlled by a monitor function which depends on the gradient of flow variables, such as density or velocity. The grid points in the adaptive grid method can be easily moved and concentrated to the regions with large density and velocity gradients, such as multi-material interface and the boundary layer. Therefore, the adaptive grid method is more accurate and efficient than the methods with stationary mesh points. In the dynamic moving mesh method, the gas-kinetic BGK equation is first reformulated under a unified coordinate transformation with grid velocity included. Then, a unified conservative gas-kinetic scheme is constructed for the viscous flow computation on moving meshes. Due to the coupling between the grid velocity and the overall solution algorithm, the Eulerian and Lagrangian methods become two limiting cases in the current gas-kinetic method. The moving grid method extends the applicable regime of the gas-kinetic scheme to the flows with free surface and moving boundaries, such as dam break problem and airfoil oscillations. In order to further increase the robustness of the moving grid scheme, the above two methods, i.e., static and dynamic ones, have been uniquely combined to move, redistribute, and remedy the distorted meshes in the fluid computations. Many numerical examples from incompressible low speed flow to the supersonic shock interaction are presented. The accuracy and robustness of the moving mesh have been fully demonstrated. In the unsteady aerodynamic flow application, the falling plate problems with the rich dynamic behavior, such as tumbling and fluttering, have been studied. Excellent agreement between the experimental measurements and the numerical computations has been obtained.

Jin, Changqiu

247

Evaporation From Lake Superior  

NASA Astrophysics Data System (ADS)

Evaporation is a critical component of the water balance of each of the Laurentian Great Lakes, and understanding the magnitude and physical controls of evaporative water losses are important for several reasons. Recently, low water levels in Lakes Superior and Michigan/Huron have had socioeconomic, ecological, and even meteorological impacts (e.g. water quality and quantity, transportation, invasive species, recreation, etc.). The recent low water levels may be due to increased evaporation, but this is not known as operational evaporation estimates are currently calculated as the residual of water or heat budgets. Perhaps surprisingly, almost nothing is known about evaporation dynamics from Lake Superior and few direct measurements of evaporation have been made from any of the Laurentian Great Lakes. This research is the first to attempt to directly measure evaporation from Lake Superior by deploying eddy covariance instrumentation. Results of evaporation rates, their patterns and controlling mechanisms will be presented. The direct measurements of evaporation are used with concurrent satellite and climate model data to extrapolate evaporation measurements across the entire lake. This knowledge could improve predictions of how climate change may impact the lake's water budget and subsequently how the water in the lake is managed.

Spence, C.; Blanken, P.; Hedstrom, N.; Leshkevich, G.; Fortin, V.; Charpentier, D.; Haywood, H.

2009-05-01

248

Disposal of Brine by Solar Evaporation.  

National Technical Information Service (NTIS)

An investigation was made to determine the rate of evaporation of brine in solar ponds by methods of energy budget, water budget and mass transfer. The investigation included the effect of salinity and dyes on solar evaporation of brine at Roswell, New Me...

C. G. Keyes N. N. Gunaji

1968-01-01

249

Method and system for producing and transporting natural gas  

SciTech Connect

A method is described for producing and transporting natural gas from a gas well(s) location, wherein said gas well(S) is connected with a gathering manifold system and said gathering manifold system is connected with a loading manifold system. The method includes the steps of: connecting a first, movable separate pressure vessel to said loading manifold system; filling said first, movable separate pressure vesel means with natural gas transmitted thereto through said gathering and loading manifold system, said natural gas being compressed to a pressure in excess of at least about 800 psia if it is not already at that pressure when entering said gathering manifold system from said gas well(s), said filling of said first, movable separate pressure vessel means being terminated after said pressure vessel means contains a selected descrete batch volume of natural gas in a relatiely static confined state compressed to a pressure in excess of at least about 800 psia, and said filling proceeding substantially continuously at a generally constant, preselected rate of flow chosen to maintain a preselected, generally constant preferred rate of withdrawal from said gas well(s); connecting a second separate pressure vessel means to said loading manifold system; switching from said first, movable separate pressure vessel means to said second pressure vessel means when said first, movable separate pressure vessel means becomes filled, without any substantialy interruption in flow; filling said second separate pressure vessel means in the same manner as said first sepate presure vessel means; replacing said filled, first movable separate pressure vessel means with an empty one.

Bresie, D.; Burns, J.; Fowler, D.

1980-07-22

250

State-of-the-art evaporation technology: Topical report  

SciTech Connect

This report discusses evaporation theory, measurement and estimation as well as the effects of water quality on evaporation. Emissions from waste effluents is also mentioned. The theory and equations to represent evaporation using energy balances, mass transport and the combination of these two methods of analysis are presented in detail. Evaporation meters and other techniques for measuring evaporation are reviewed. A discussion of ways to estimate areal evaporation is presented along with criteria which affects evaporation pond design. The effects of chemical monolayers and salinity on the rate of evaporation is cited and discussed to indicated problems associated with most industrial waste effluents. The problem of monitoring emissions resulting from evaporation ponds associated with industrial waste emissions is also presented.

Hasfurther, V.R.; Haass, M.J.

1986-09-01

251

Evaporative Precooler Retrofit for Air Cooled Condensers. Small Scale Appropriate Technology Grant Program.  

National Technical Information Service (NTIS)

Three methods of evaporative cooling were evaluated; direct evaporative cooling of the condenser coil (spray directly on condenser coil), wetted media acting as evaporator and eliminator, and a spray type with eliminator. The direct spray achieved the low...

J. R. Campbell

1984-01-01

252

The influence of air and vacuum thermal treatments on the NO 2 gas sensitivity of WO 3 thin films prepared by thermal evaporation  

Microsoft Academic Search

WO3 films with thickness of 80 nm have been thermally evaporated onto Si3N4\\/Si substrates. The films have been initially treated in oxygen by a 24-h-long annealing at 300°C and 500°C. XPS measurements, to follow W 4f, O 1s peaks and the valence band, have been performed on these samples as prepared and after successive ultra high vacuum (UHV) thermal treatments.

L. Lozzi; L Ottaviano; M Passacantando; S Santucci; C Cantalini

2001-01-01

253

Polypyrrole thin films for gas sensors prepared by Matrix-Assisted Pulsed Laser Evaporation technology: Effect of deposition parameters on material properties  

Microsoft Academic Search

Thin films of polypyrrole (PPY) were prepared by Matrix-Assisted Pulsed Laser Evaporation (MAPLE) technology from two matrices: water and dimethylsulfoxide (DMSO). The deposition was carried out using a KrF excimer laser (laser fluence F ranged from 0.1 to 0.6 J cm?2). This work deals with optimization of two deposition parameters – laser fluence and number of pulses – for both matrices.

Dušan Kopecký; Martin Vr?ata; Filip Vysloužil; Vladimír Myslík; P?emysl Fitl; Ond?ej Ekrt; Pavel Mat?jka; Miroslav Jelínek; TomᚠKocourek

2009-01-01

254

Methods for gas detection using stationary hyperspectral imaging sensors  

SciTech Connect

According to one embodiment, a method comprises producing a first hyperspectral imaging (HSI) data cube of a location at a first time using data from a HSI sensor; producing a second HSI data cube of the same location at a second time using data from the HSI sensor; subtracting on a pixel-by-pixel basis the second HSI data cube from the first HSI data cube to produce a raw difference cube; calibrating the raw difference cube to produce a calibrated raw difference cube; selecting at least one desired spectral band based on a gas of interest; producing a detection image based on the at least one selected spectral band and the calibrated raw difference cube; examining the detection image to determine presence of the gas of interest; and outputting a result of the examination. Other methods, systems, and computer program products for detecting the presence of a gas are also described.

Conger, James L. (San Ramon, CA); Henderson, John R. (Castro Valley, CA)

2012-04-24

255

A RP-LC method with evaporative light scattering detection for the assay of simethicone in pharmaceutical formulations  

Microsoft Academic Search

A reversed-phase liquid chromatographic method has been developed and validated for the determination of the polydimethylsiloxane (PDMS) component of Simethicone, which is used as an anti-foaming agent in pharmaceutical formulations. The method involves acidification to neutralise antacid components of the formulation, then a single extraction of the PDMS with dichloromethane. This is followed by separation with a reversed-phase column using

Douglas E Moore; Tina X Liu; William G Miao; Alison Edwards; Russell Elliss

2002-01-01

256

Control method for mixed refrigerant based natural gas liquefier  

DOEpatents

In a natural gas liquefaction system having a refrigerant storage circuit, a refrigerant circulation circuit in fluid communication with the refrigerant storage circuit, and a natural gas liquefaction circuit in thermal communication with the refrigerant circulation circuit, a method for liquefaction of natural gas in which pressure in the refrigerant circulation circuit is adjusted to below about 175 psig by exchange of refrigerant with the refrigerant storage circuit. A variable speed motor is started whereby operation of a compressor is initiated. The compressor is operated at full discharge capacity. Operation of an expansion valve is initiated whereby suction pressure at the suction pressure port of the compressor is maintained below about 30 psig and discharge pressure at the discharge pressure port of the compressor is maintained below about 350 psig. Refrigerant vapor is introduced from the refrigerant holding tank into the refrigerant circulation circuit until the suction pressure is reduced to below about 15 psig, after which flow of the refrigerant vapor from the refrigerant holding tank is terminated. Natural gas is then introduced into a natural gas liquefier, resulting in liquefaction of the natural gas.

Kountz, Kenneth J. (Palatine, IL); Bishop, Patrick M. (Chicago, IL)

2003-01-01

257

PARTICLE-GAS DYNAMICS WITH ATHENA: METHOD AND CONVERGENCE  

SciTech Connect

The Athena magnetohydrodynamics code has been extended to integrate the motion of particles coupled with the gas via aerodynamic drag in order to study the dynamics of gas and solids in protoplanetary disks (PPDs) and the formation of planetesimals. Our particle-gas hybrid scheme is based on a second-order predictor-corrector method. Careful treatment of the momentum feedback on the gas guarantees exact conservation. The hybrid scheme is stable and convergent in most regimes relevant to PPDs. We describe a semi-implicit integrator generalized from the leap-frog approach. In the absence of drag force, it preserves the geometric properties of a particle orbit. We also present a fully implicit integrator that is unconditionally stable for all regimes of particle-gas coupling. Using our hybrid code, we study the numerical convergence of the nonlinear saturated state of the streaming instability. We find that gas flow properties are well converged with modest grid resolution (128 cells per pressure length {eta}r for dimensionless stopping time {tau} {sub s} = 0.1) and an equal number of particles and grid cells. On the other hand, particle clumping properties converge only at higher resolutions, and finer resolution leads to stronger clumping before convergence is reached. Finally, we find that the measurement of particle transport properties resulted from the streaming instability may be subject to error of about {+-}20%.

Bai Xuening; Stone, James M., E-mail: xbai@astro.princeton.ed, E-mail: jstone@astro.princeton.ed [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)

2010-10-15

258

Experimental and theoretical investigation of an evaporative fuel system for heat engines  

Microsoft Academic Search

The evaporative gas turbine (EvGT) pilot plant has been in operation at Lund University in Sweden since 1997. This project has led to improved knowledge of evaporative techniques and the concept of introducing fuel into gas turbines by evaporation. This results in, amongst others, power augmentation, efficiency increase and lower emissions. This article presents the experimental and theoretical results of

Marcus Thern; Torbjörn Lindquist; Tord Torisson

2007-01-01

259

Comparison of ultraviolet detection, evaporative light scattering detection and charged aerosol detection methods for liquid-chromatographic determination of anti-diabetic drugs.  

PubMed

Recently, charged aerosol detection (CAD), a new kind of universal detection method, has been widely employed in the HPLC system. In the present study, four kinds of anti-diabetic drug standards, glipizide, gliclazide, glibenclamide and glimepiride were determined by ultraviolet (UV) detection, evaporative light scattering detection (ELSD) and the aforementioned CAD. The results were compared with reference to linearity, accuracy, precision and limit of detection (LOD). All of the experiments were performed on a reverse phase column with water and acetonitrile as the mobile phase. Separations were achieved under the same chromatographic conditions for each detection method. As a result, CAD generated nearly uniform responses compared with UV detection and ELSD. It showed the best accuracy and LOD among 3 detectors and had similar precision with UV detection at higher concentrations while UV detection showed a better precision at lower concentrations than did CAD or ELSD. The LOD of CAD, in fact, can be up to two times higher than that of ELSD. The UV and ELSD linearity was satisfactory at R(2)>0.99, though in the case of CAD, a log-log transformation was needed. The proposed methods were also applied to the real anti-diabetic drugs and diabetes-related dietary supplements. PMID:20004074

Shaodong, Jia; Lee, Won Jun; Ee, Ji Won; Park, Jeong Hill; Kwon, Sung Won; Lee, Jeongmi

2009-10-31

260

Method of operation for a gas turbine engine  

Microsoft Academic Search

A method is described for operating gas turbine engine having a compression section, a turbine section, an annular flow path for working medium gases which extends through the sections of the engine, a rotor assembly and a stator assembly, the engine further including a bearing housing which defines a bearing compartment in an inner cavity of the engine, a bearing

Hovan

1986-01-01

261

Gas Turbine Engine and Method of Assembling Same.  

National Technical Information Service (NTIS)

A method of assembling a gas turbine engine that includes rotatably coupling a first low-pressure turbine rotor to a high-pressure turbine, rotatably coupling a second low pressure turbine rotor to the first low-pressure turbine rotor, and rotatably coupl...

J. L. Henry

2004-01-01

262

New Spectroscopic Methods in Gas-Phase Chemical Kinetics  

Microsoft Academic Search

The possibilities provided by the application of advances in laser technology to the solution of problems in gas-phase chemical kinetics have been analysed. The basic principles of various laser methods for producing and recording active chemical species have been described. Examples of the use of lasers to study the reactions of radicals and excited species, in the diagnostics of complex

Oleg M. Sarkisov; S. G. Cheskis

1985-01-01

263

Field investigation of evaporation from freshwater tailings  

SciTech Connect

Safe and economical storage of tailings is now a major consideration in the operation of many mining operations. Tailings in slurried form, particularly if they have a significant clay content, can take a very long time to consolidate under the action of self-weight consolidation alone. However, if the operation is located in an area of high potential evaporation, this can be used to accelerate the rate of tailings densification. This paper presents a study of the evaporation behavior of a clayey tailings slurry deposited into an evaporation pond in the southwest of Western Australia. Over a six-month period, the rate of evaporation from the tailings surface was monitored using the Bowen Ratio method and the microlysimeter method. This was compared with the evaporation from a Class A pan located nearby. The tailings underwent very significant cracking as drying proceeded, and it was found that these cracks had a significant influence on the overall rate of evaporation once the top surface of the deposit started to desaturate. A large strain consolidation model was used to model the behavior, and the algorithm used in this model to include the effects of evaporation is shown to provide a reasonable prediction of the observed evaporation behavior.

Fujiyasu, Yoshimasa; Fahey, M.; Newson, T.

2000-06-01

264

Evaporation of urea at atmospheric pressure.  

PubMed

Aqueous urea solution is widely used as reducing agent in the selective catalytic reduction of NO(x) (SCR). Because reports of urea vapor at atmospheric pressure are rare, gaseous urea is usually neglected in computational models used for designing SCR systems. In this study, urea evaporation was investigated under flow reactor conditions, and a Fourier transform infrared (FTIR) spectrum of gaseous urea was recorded at atmospheric pressure for the first time. The spectrum was compared to literature data under vacuum conditions and with theoretical spectra of monomolecular and dimeric urea in the gas phase calculated with the density functional theory (DFT) method. Comparison of the spectra indicates that urea vapor is in the monomolecular form at atmospheric pressure. The measured vapor pressure of urea agrees with the thermodynamic data obtained under vacuum reported in the literature. Our results indicate that considering gaseous urea will improve the computational modeling of urea SCR systems. PMID:21381736

Bernhard, Andreas M; Czekaj, Izabela; Elsener, Martin; Wokaun, Alexander; Kröcher, Oliver

2011-03-07

265

Radon concentration in soil gas: a comparison of methods  

Microsoft Academic Search

Various methods to determine 222Rn concentration in soil gas were tested at two sites with different soil types in a depth of about 1m. They included instantaneous (spot), continuous (real-time) and time-averaging procedures. The first test site had a porous soil with high gravel content. At this site, radon concentrations obtained with the different methods agreed within the error limits

F. Ruckerbauer; R. Winkler

2001-01-01

266

Utility of Penman–Monteith, Priestley–Taylor, reference evapotranspiration, and pan evaporation methods to estimate pasture evapotranspiration  

Microsoft Academic Search

Actual evapotranspiration (ETa) was measured at 30-min resolution over a 19-month period (September 28, 2000–April 23, 2002) from a nonirrigated pasture site in Florida, USA, using eddy correlation methods. The relative magnitude of measured ETa (about 66% of long-term annual precipitation at the study site) indicates the importance of accurate ETa estimates for water resources planning. The time and cost

David M. Sumner; Jennifer M. Jacobs

2005-01-01

267

Evaporation, Boiling and Bubbles  

ERIC Educational Resources Information Center

|Evaporation and boiling are both terms applied to the change of a liquid to the vapour/gaseous state. This article argues that it is the formation of bubbles of vapour within the liquid that most clearly differentiates boiling from evaporation although only a minority of chemistry textbooks seems to mention bubble formation in this context. The…

Goodwin, Alan

2012-01-01

268

Instrument for Measuring Evaporation.  

National Technical Information Service (NTIS)

An evaporation rate meter, or evaporimeter, has been devised that shows promise of directly measuring the rate of evaporation near the sea surface. The simplicity of the instrument indicates that it may be of interest to oceanographers, and possibly to me...

A. H. Schooley

1965-01-01

269

Optical trapping and evaporative cooling of fermionic atoms  

NASA Astrophysics Data System (ADS)

This dissertation describes the development of the first stable optical trap for neutral atoms and its application to studies of interactions between and evaporative cooling of a gas of fermionic atoms. This work lays the foundation for future investigations of quantum statistical effects in a dilute, ultracold gas of fermionic atoms in which the temperature, density and interaction strength can be independently controlled. Such studies may include the observation of superfluidity via Cooper pair formation at a high critical temperature. In addition, the development of a stable optical trap impacts a wide variety of applications including fundamental precision measurements, quantum computing, improved frequency standards and the precise manipulation of atoms and molecules. Optical traps are ideally suited for studies of interacting Fermi gases since they are able to confine stable two-state mixtures of fermionic atoms. The ability to trap multiple states enables ultracold collisions, which would otherwise be forbidden by the exclusion principle in a single-state fermionic vapor. However, optical traps have previously suffered from residual heating and loss mechanisms, which have limited trap lifetimes to several seconds. Using an ultrastable carbon dioxide laser to confine atoms in an ultrahigh vacuum environment, we minimize all known sources of residual heating including those due to fluctuations in the laser intensity and position. By this method we obtain trap lifetimes of 370 seconds, limited by the background gas pressure of <10-11 Torr, with residual heating rates of < 50 nanoKelvin/sec. The construction of a stable optical trap has enabled the first experimental studies of evaporative cooling of a two-state mixture of lithium fermions. By monitoring the rate of evaporation of atoms from the trap we directly measure a large low-energy cross section predicted to exist for 6Li. Based on the existence of this large interaction strength, an optically trapped gas of lithium atoms is expected to be a promising candidate for the observation of superfluidity in a dilute, ultracold, interacting Fermi gas. Ultracold temperatures and high phase space densities can be achieved in this system through forced evaporative cooling. In this process, the highest energy atoms are selectively removed from the trap by adiabatically lowering the well depth. Using this technique, a temperature of 2.4 ?K with a corresponding phase space density of 1.6 × 10-3 is achieved. Based on a theoretical model of evaporative cooling we describe in this dissertation, we expect that modest improvements to this system should enable cooling to temperatures below the Fermi temperature and possibly below the critical temperature for Cooper pair formation.

O'Hara, Kenneth Martin

2000-11-01

270

A novel method for the determination of guanfacine in urine by gas chromatography-mass spectrometry.  

PubMed

Guanfacine (Tenex), an antihypertensive available since 1975, has recently been indicated for the treatment of attention deficit hyperactivity disorder in children (Intuniv). Because of this new usage, a gas chromatography-mass spectrometry method was developed and validated for the determination of guanfacine in urine. Guanfacine and 100 ng of protriptyline (internal standard) were extracted from 1.0 mL urine with 0.5 mL of saturated carbonate/bicarbonate buffer and 2 mL of ethyl acetate. The solvent extract was evaporated and derivatized with heptaflurobutyric anhydride in n-butyl chloride. Chromatographic separation was achieved using a DB-5 capillary column (30 m x 0.32 mm, 0.25 microm). Ions monitored for guanfacine were m/z 86.1, 272.1, and 274.1, and ions monitored for protriptyline were m/z 191.1 and 189.1. Concentrations were determined using calibrators over the range of 0.1-2.0 mg/L. The linear regression for all calibration curves had r2 values > or = 0.99. The limit of detection was 0.05 mg/L; limit of quantitation was 0.1 mg/L; and upper limit of linearity was 10.0 mg/L. Percent recovery of guanfacine at 0.1 and 2.0 mg/L was 93% and 71%, respectively. The method was found acceptable for routine quantitative analysis of guanfacine in urine. PMID:19007502

Haglock, Carrie; Wolf, Carl; Poklis, Alphonse

2008-10-01

271

Segmented inlet nozzle for gas turbine, and methods of installation  

DOEpatents

A gas turbine nozzle guide vane assembly is formed of individual arcuate nozzle segments. The arcuate nozzle segments are elastically joined to each other to form a complete ring, with edges abutted to prevent leakage. The resultant nozzle ring is included within the overall gas turbine stationary structure and secured by a mounting arrangement which permits relative radial movement at both the inner and outer mountings. A spline-type outer mounting provides circumferential retention. A complete rigid nozzle ring with freedom to "float" radially results. Specific structures are disclosed for the inner and outer mounting arrangements. A specific tie-rod structure is also disclosed for elastically joining the individual nozzle segments. Also disclosed is a method of assembling the nozzle ring subassembly-by-subassembly into a gas turbine employing temporary jacks.

Klompas, Nicholas (Scotia, NY)

1985-01-01

272

Method of immobilizing carbon dioxide from gas streams  

DOEpatents

This invention is a method for rapidly and continuously immobilizing carbon dioxide contained in various industrial off-gas streams, the carbon dioxide being immobilized as dry, stable, and substantially water-insoluble particulates. Briefly, the method comprises passing the gas stream through a fixed or fluidized bed of hydrated barium hydroxide to remove and immobilize the carbon dioxide by converting the bed to barium carbonate. The method has several important advantages: it can be conducted effectively at ambient temperature; it provides a very rapid reaction rate over a wide range of carbon dioxide concentrations; it provides high decontamination factors; and it has a high capacity for carbon dioxide. The invention is especially well suited for the removal of radioactive carbon dioxide from off-gases generated by nuclear-fuel reprocessing facilities and nuclear power plants.

Holladay, David W. (Knoxville, TN); Haag, Gary L. (Oliver Springs, TN)

1979-01-01

273

A parametric study of a multiple droplet spray evaporator  

Microsoft Academic Search

In this paper, a closed form solution is presented for spray evaporation on the surface of a spray evaporator. A parametric analysis is performed using a multiple droplet model. Droplets on the evaporator surface are considered as point sinks of heat in a fixed geometric pattern. The method of image systems is used to satisfy both the heat conduction equation

J. J. Rizza

1984-01-01

274

Extracting phreatic evaporation from remotely sensed maps of evapotranspiration  

Microsoft Academic Search

One of the most important parameters related to soil salinization is the direct evaporation from the groundwater (phreatic evaporation). If the groundwater table is sufficiently close to the surface, groundwater will evaporate through capillary rise. In recent years, several methods have been suggested to map evapotranspiration (ET) on the basis of remote sensing images. These maps represent the sum of

P. Brunner; H. T. Li; W. Kinzelbach; W. P. Li; X. G. Dong

2008-01-01

275

Sample Analysis Results for a Benchscale Evaporator Test Using a Hanford Tank 241-AN-102 Sample  

SciTech Connect

This report provides the analytical results of samples taken during the low-activity waste evaporator process demonstration conducted at the Savannah River Technology Center with a 15-liter sample of Hanford tank 241-AN102 pretreated radioactive supernate. The objective of the task was to determine the concentration of various organic, inorganic and radionuclide constituents of potential concern and physical properties of the evaporator feed, concentrate, condensate and off gas for the Hanford River Protection Project. Over 150 samples and blanks were collected and analyzed in accordance with EPA methods. One hundred nineteen target organic analyze concentrations were shown to be less than the minimum quantitative limits in all samples (feed, concentrate, condensate, and off gas samples).Tetrahydrofuran (THF) was present in evaporator samples. THF was the most concentrated volatile compound detected in the off gas. No pesticides or polychlorinated biphenyls (PCBs) were detected in any evaporator sample. Very low levels of some dioxins and furans were reported in the off-gas samples, but are thought to have been due to contamination. Most of the sample collection, sample preparation, and sample analyses provided results with sufficient pedigree to support the rigor associated with regulatory application of these results.

Ferrara, D.M.

2003-08-25

276

Evaporative cooling of trapped atoms  

SciTech Connect

This report discusses the following topics on evaporative cooling of trapped atoms: Theoretical models for evaporative cooling; the role of collisions for real atoms; experimental techniques and summary of evaporative cooling experiments. 166 refs., 6 figs., 3 tabs.

Ketterle, W.; Van Druten, N.J. [Massachusetts Inst. of Technology, Cambridge, MA (United States)

1996-12-31

277

Evaporative Cooling of Trapped Atoms  

Microsoft Academic Search

This report discusses the following topics on evaporative cooling of trapped atoms: Theoretical models for evaporative cooling; the role of collisions for real atoms; experimental techniques and summary of evaporative cooling experiments. 166 refs., 6 figs., 3 tabs.

Wolfgang Ketterle; N. J. Van Druten

1996-01-01

278

Development of a rapid and convenient method to separate eight ginsenosides from Panax ginseng by high-speed counter-current chromatography coupled with evaporative light scattering detection.  

PubMed

Ginsenosides exhibit diverse biological activities and are major well-known components isolated from the radix of Panax ginseng C.A. Meyer. In the present work, a rapid and facile method for the separation and purification of eight ginsenosides from P. ginseng by high-speed counter-current chromatography coupled with evaporative light scattering detector (HSCCC-ELSD) was successfully developed. The crude samples for HSCCC separation were first purified from ginseng extract using a macroporous resin; the extract was loaded onto a Diaion-HP20 column and fractionated by methanol and water gradient elution. The ginsenosides-protopanaxadiol (PPD) and protopanaxatriol (PPT) fractions were subsequently eluted with 65 and 80% methanol and water gradient elution, respectively. Furthermore, these two fractions were separated by HSCCC-ELSD. The two-phase solvent system used for separation was composed of chloroform/methanol/water/isopropanol at a volume ratio of 4:3:2:1. Each fraction obtained was collected and dried, yielding the following eight ginsenosides: Rg(1), Re, Rf, Rh(1), Rb(1), Rc Rb(2) and Rd. The purity of these ginsenosides was greater than 97% as assessed by HPLC-ELSD, and their structures were characterized by electrospray-ionization mass spectrometry (ESI-MS) and nuclear magnetic resonance spectroscopy. This is the first report regarding the separation of the ginsenosides Rh(1), Rb(2) and Rc from P. ginseng by HSCCC. PMID:21491596

Shehzad, Omer; Ha, In Jin; Park, Youmie; Ha, Young Wan; Kim, Yeong Shik

2011-04-13

279

RF-magnetron sputtering and reactive evaporation - Two fast methods preparing a-Si:H films usable for solar cell application  

NASA Astrophysics Data System (ADS)

Techniques and equipment used to manufacture a-Si solar cells using magnetron-sputtering (MS) and reactive evaporation (REV) are described and cell performance is assessed. An 18-20 nm/min deposition rate was achieved using MS with a 20 cm gap between the sputterer and the cell surface. A low defect density was obtained in a narrow range of hydrogen partial pressure. Cells with a hydrogen content of 12 at. pct displayed high photoconductivity and low defect densities. REV films formed in ultra-high vacuum using an electron gun source were deposited at 9 nm/min. A thermal dissociator provided feedstocks of hydrogen and the doping gases. A hydrogen concentration of 8-9 at. pct was attained. Efficiencies of 2.25 and 2.0 percent have thus far been realized for MS-formed Mo/n(+)-i(Pd) Schottky type and Cr/p(+)-i-n(+)/Pd cells, respectively. A potential conversion efficiency of 4.2 percent has been projected for a-Si formed by the MS method.

Mueller, W.; Iselborn, S.; Pirrung, J.; Schroeder, B.; Geiger, J.

280

Improvement in Thermal-Ionization Mass Spectrometry (TIMS) using Total Flash Evaporation (TFE) method for lanthanides isotope ratio measurements in transmutation targets  

SciTech Connect

The experiments involved in the PHENIX french nuclear reactor to obtain precise and accurate data on the total capture cross sections of the heavy isotopes and fission products require isotopic ratios measurements with uncertainty of a few per mil. These accurate isotopic ratio measurements are performed with mass spectrometer equipped with multi-collector system. The major difficulty for the analyses of these actinides and fission products is the low quantity of the initial powder enclosed in steel container (3 to 5 mg) and the very low quantities of products formed (several {mu}g) after irradiation. Specific analytical developments are performed by Thermal Ionization Mass Spectrometry (TIMS) to be able to analyse several nanograms of elements with this technique. A specific method of acquisition named Total Flash Evaporation was adapted in this study in the case of lanthanide measurements for quantity deposited on the filament in the order of 2 ng and applied on irradiated fuel. To validate the analytical approach and discuss about the accuracy of the data, the isotopic ratios obtained by TIMS are compared with other mass spectrometric techniques such as Multiple-Collector Inductively Coupled Plasma Mass Spectrometer (MC-ICPMS). (authors)

Mialle, S.; Gourgiotis, A.; Aubert, M.; Stadelmann, G.; Gautier, C.; Isnard, H. [Commissariat a l'Energie Atomique, CEA Saclay, DEN/DPC/SECR/LANIE, 91191 Gif sur Yvette (France); Chartier, F. [Commissariat a l'Energie Atomique, CEA Saclay, DEN/DPC, 91191 Gif sur Yvette (France)

2011-07-01

281

Urban Signatures: Evaporation (WMS)  

NSDL National Science Digital Library

Big cities influence the environment around them. For example, urban areas are typically warmer than their surroundings. Cities are strikingly visible in computer models that simulate the Earths land surface. This visualization shows evaporation rates predicted by the Land Information System (LIS) for a day in June 2001. Evaporation is lower in the cities because water tends to run off pavement and into drains, rather than being absorbed by soil and plants from which it later evaporates. Only part of the global computation is shown, focusing on the highly urbanized northeast corridor in the United States, including the cities of Boston, New York, Philadelphia, Baltimore, and Washington.

Delabeaujardiere, Jeff

2005-05-27

282

Evaporation, Condensation, and Precipitation  

NSDL National Science Digital Library

After completion of this project students should have an understanding of evaporation, condensation, and precipitation in the water cycle. Use the websites provided to answer the questions. Record your answers on the spreadsheet provided. Do you understand how the water cycle works? Begin by watching this short video about the water cycle.water cycle video Use the website to define condensation, precipitation, and evaporation?water cycle List the different types of precipitation from the site.types of precipitation Follow the directions to the experiment on this website to get a better understanding of how evaporation takes ...

Brown, Miss

2009-10-21

283

Method and apparatus for controlling gas evolution from chemical reactions  

DOEpatents

The present invention is directed toward monitoring a thermally driven gas evolving chemical reaction with an acoustic apparatus. Signals from the acoustic apparatus are used to control a heater to prevent a run-away condition. A digestion module in combination with a robotic arm further automate physical handling of sample material reaction vessels. The invention is especially useful for carrying out sample procedures defined in EPA Methods SW-846.

Skorpik, James R. (Kennewick, WA); Dodson, Michael G. (Richland, WA)

1999-01-01

284

Method and apparatus for controlling gas evolution from chemical reactions  

DOEpatents

The present invention is directed toward monitoring a thermally driven gas evolving chemical reaction with an acoustic apparatus. Signals from the acoustic apparatus are used to control a heater to prevent a run-away condition. A digestion module in combination with a robotic arm further automate physical handling of sample material reaction vessels. The invention is especially useful for carrying out sample procedures defined in EPA Methods SW-846. 8 figs.

Skorpik, J.R.; Dodson, M.G.

1999-05-25

285

Gas phase fractionation method using porous ceramic membrane  

DOEpatents

Flaw-free porous ceramic membranes fabricated from metal sols and coated onto a porous support are advantageously used in gas phase fractionation methods. Mean pore diameters of less than 40 .ANG., preferably 5-20 .ANG. and most preferably about 15 .ANG., are permeable at lower pressures than existing membranes. Condensation of gases in small pores and non-Knudsen membrane transport mechanisms are employed to facilitate and increase membrane permeability and permselectivity.

Peterson, Reid A. (Madison, WI); Hill, Jr., Charles G. (Madison, WI); Anderson, Marc A. (Madison, WI)

1996-01-01

286

Quantifying nonisothermal subsurface soil water evaporation  

NASA Astrophysics Data System (ADS)

Accurate quantification of energy and mass transfer during soil water evaporation is critical for improving understanding of the hydrologic cycle and for many environmental, agricultural, and engineering applications. Drying of soil under radiation boundary conditions results in formation of a dry surface layer (DSL), which is accompanied by a shift in the position of the latent heat sink from the surface to the subsurface. Detailed investigation of evaporative dynamics within this active near-surface zone has mostly been limited to modeling, with few measurements available to test models. Soil column studies were conducted to quantify nonisothermal subsurface evaporation profiles using a sensible heat balance (SHB) approach. Eleven-needle heat pulse probes were used to measure soil temperature and thermal property distributions at the millimeter scale in the near-surface soil. Depth-integrated SHB evaporation rates were compared with mass balance evaporation estimates under controlled laboratory conditions. The results show that the SHB method effectively measured total subsurface evaporation rates with only 0.01-0.03 mm h-1difference from mass balance estimates. The SHB approach also quantified millimeter-scale nonisothermal subsurface evaporation profiles over a drying event, which has not been previously possible. Thickness of the DSL was also examined using measured soil thermal conductivity distributions near the drying surface. Estimates of the DSL thickness were consistent with observed evaporation profile distributions from SHB. Estimated thickness of the DSL was further used to compute diffusive vapor flux. The diffusive vapor flux also closely matched both mass balance evaporation rates and subsurface evaporation rates estimated from SHB.

Deol, Pukhraj; Heitman, Josh; Amoozegar, Aziz; Ren, Tusheng; Horton, Robert

2012-11-01

287

Turbulence Effects during Evaporation of Drops in Clusters,  

National Technical Information Service (NTIS)

A model of droplet evaporation in clusters and the exchange processes between the cluster and the gas phase surrounding it are presented. This model is developed for use as a subscale model in calculations of spray evaporation and combustion and thus desc...

J. Bellan K. Harstad

1988-01-01

288

Large Eddy Simulation of Evaporating Kerosene Sprays  

Microsoft Academic Search

Large Eddy Simulation (LES) is applied to turbulent, kerosene sprays and the effect of turbulence and temperature fluctuations on the structure of the sprays under cold and evaporating conditions is discussed. A Lagrangian formula- tion is adopted for the particle dispersion coupled with an Eulerian description for the carrier gas. A stochastic model has been used for the representation of

W. P. Jones; S. Lyra; A. J. Marquis

289

The study on the interdependence of spray characteristics and evaporation history of fuel spray in high temperature air crossflow  

NASA Astrophysics Data System (ADS)

A numerical calculation method is used to predict the variation of the characteristics of fuel spray moving in a high temperature air crossflow, mainly, Sauter mean diameter SMD, droplet size distribution index N of Rosin-Rammler distribution and evaporation percentage changing with downstream distance X from the nozzle. The effect of droplet heat-up period evaporation process and forced convection are taken into full account; thus, the calculation model is a very good approximation to the process of spray evaporation in a practical combustor, such as ramjet, aero-gas turbine, liquid propellant rocket, diesel and other liquid fuel-powered combustion devices. The changes of spray characteristics N, SMD and spray evaporation percentage with air velocity, pressure, temperature, fuel injection velocity, and the initial spray parameters are presented.

Zhu, J. Y.; Chin, J. S.

1986-06-01

290

Statistical Methods Handbook for Advanced Gas Reactor Fuel Materials  

SciTech Connect

Fuel materials such as kernels, coated particles, and compacts are being manufactured for experiments simulating service in the next generation of high temperature gas reactors. These must meet predefined acceptance specifications. Many tests are performed for quality assurance, and many of these correspond to criteria that must be met with specified confidence, based on random samples. This report describes the statistical methods to be used. The properties of the tests are discussed, including the risk of false acceptance, the risk of false rejection, and the assumption of normality. Methods for calculating sample sizes are also described.

J. J. Einerson

2005-05-01

291

Flash Evaporator Systems Test.  

National Technical Information Service (NTIS)

A flash evaporator heat rejection system representative of that proposed for the space shuttle orbiter underwent extensive system testing at the NASA Johnson Space Center (JSC) to determine its operational suitability and to establish system performance/o...

J. B. Dietz

1976-01-01

292

DIAGNOSIS OF EVAPORATIVE LEAKS AND SENSOR FAULTS IN A VEHICLE FUEL SYSTEM  

Microsoft Academic Search

This paper describes a vacuum-decay based evaporative leak detection procedure for vehicle fuel systems. A physical model for an evaporative system is proposed containing parts for fuel evaporation, leakage flow and canister flow. Two methods for detecting evaporative leakages based on the model is presented. Both methods can detect a 0.5 mm diameter leakage in a laboratory environment. According to

Ingemar Andersson; Erik Frisk

293

Mixed feed evaporator  

DOEpatents

In the preparation of the gaseous reactant feed to undergo a chemical reaction requiring the presence of steam, the efficiency of overall power utilization is improved by premixing the gaseous reactant feed with water and then heating to evaporate the water in the presence of the gaseous reactant feed, the heating fluid utilized being at a temperature below the boiling point of water at the pressure in the volume where the evaporation occurs.

Vakil, Himanshu B. (Schenectady, NY); Kosky, Philip G. (Ballston Lake, NY)

1982-01-01

294

Heat and mass transfer for liquid film evaporation along a vertical plate covered with a thin porous layer  

Microsoft Academic Search

The purpose of this work is to evaluate the heat and mass enhancement of liquid film evaporation by covering a porous layer on the plate. Liquid and gas streams are approached by two coupled laminar boundary layers incorporated with non-Darcian modes. The numerical solution is obtained by utilizing a fully implicit finite difference method and examined in detail for the

Jin-Sheng Leu; Jiin-Yuh Jang; Yin Chou

2006-01-01

295

Evaluation of the freeze-thaw/evaporation process for the treatment of produced waters. Final report, August 1992--August 1996.  

National Technical Information Service (NTIS)

The use of freeze-crystallization is becoming increasingly acknowledged as a low-cost, energy-efficient method for purifying contaminated water. The natural freezing process can be coupled with natural evaporative processes to treat oil and gas produced w...

J. A. Harju J. E. Boysen J. L. Mefford J. R. Kirsch K. L. Walker

1996-01-01

296

Reactive evaporation in ionized gases.  

PubMed

By conventional reactive evaporation techniques, films with a certain deviation from stochiometric composition and, therefore, increased absorptance and dielectric losses were obtained. By ionization of the residual gas a considerable increase of reactivity has been achieved. The construction of a discharge tube with a region of high current density for ionization is described. The tube was arranged inside a bell jar. The ionized gas emerged from a nozzle in the wall of the tube directly into the high vacuum region. Production parameters for SiO(2), SiO(x)N(y), and TiO(2) films were evaluated. On unheated substrates SiO(2) films, which are practically free of absorptance down to 190 nm, and TiO(2) films with refractive indices up to 2.3, were obtained. PMID:20111347

Heitmann, W

1971-11-01

297

A generalized method for predicting gas/oil miscibility  

SciTech Connect

An equilibrium-cell simulator provides reliable estimates of gas/oil minimum miscibility pressure (MMP) with a correlation of residual oil against capillary number. The basic flash calculations of the equilibrium cell are supplemented by a number of PVT and fluid-flow modeling techniques that provide a reasonable simulation of slim-tube performance. A PVT stability calculation has been incorporated as an option for systems where flash convergence is difficult. Interfacial tension (IFT) may be calculated either by the method of parachors or by method based on critical-point scaling theory. An experimental correlation is presented for residual oil reduction with capillary number. The relative permeabilities are varied between the fully miscible bounds as a function of capillary number. The slim-tube recovery results have been calibrated against 110 experimental runs for 21 different oils. Recovery by hydrocarbon gas is generally predicted within 10%; recovery by N/sub 2/ and CO/sub 2/ is generally predicted to within 15%. The program logic is designed to be most accurate in the miscible region. The simulator will typically give a priori estimate of MMP within 10% and show the relative effects of changes in injection gas composition and system pressure. The simulator may be calibrated to an experimental recovery point . An oil specific calibration gives much higher accuracy than the predictions that use the default parameters.

Emanuel, A.S.; Behrens, R.A.; McMillen, T.J.

1986-09-01

298

Self-contained cryogenic gas sampling apparatus and method  

DOEpatents

Apparatus for obtaining a whole gas sample, is composed of: a sample vessel having an inlet for receiving a gas sample; a controllable valve mounted for controllably opening and closing the inlet; a valve control coupled to the valve for opening and closing the valve at selected times; a portable power source connected for supplying operating power to the valve control; and a cryogenic coolant in thermal communication with the vessel for cooling the interior of the vessel to cryogenic temperatures. A method is described for obtaining an air sample using the apparatus described above, by: placing the apparatus at a location at which the sample is to be obtained; operating the valve control to open the valve at a selected time and close the valve at a selected subsequent time; and between the selected times maintaining the vessel at a cryogenic temperature by heat exchange with the coolant. 3 figs.

McManus, G.J.; Motes, B.G.; Bird, S.K.; Kotter, D.K.

1996-03-26

299

Self-contained cryogenic gas sampling apparatus and method  

DOEpatents

Apparatus for obtaining a whole gas sample, composed of: a sample vessel having an inlet for receiving a gas sample; a controllable valve mounted for controllably opening and closing the inlet; a valve control coupled to the valve for opening and closing the valve at selected times; a portable power source connected for supplying operating power to the valve control; and a cryogenic coolant in thermal communication with the vessel for cooling the interior of the vessel to cryogenic temperatures. A method of obtaining an air sample using the apparatus described above, by: placing the apparatus at a location at which the sample is to be obtained; operating the valve control to open the valve at a selected time and close the valve at a selected subsequent time; and between the selected times maintaining the vessel at a cryogenic temperature by heat exchange with the coolant.

McManus, Gary J. (Idaho Falls, ID); Motes, Billy G. (Idaho Falls, ID); Bird, Susan K. (Idaho Falls, ID); Kotter, Dale K. (Shelley, ID)

1996-01-01

300

Cytogenetic studies of stainless steel welders using the tungsten inert gas and metal inert gas methods for welding  

Microsoft Academic Search

Cytogenetic damage was studied in lymphocytes from 23 welders using the Tungsten Inert Gas (TIG), and 21 welders using the Metal Inert Gas (MIG) and\\/ or Metal Active Gas (MAG) methods on stainless steel (SS). A matched reference group I, and a larger reference group II of 94 subjects studied during the same time period, was established for comparison. Whole

Øyvind Jelmert; Inger-Lise Hansteen; Sverre Langård

1995-01-01

301

In situ cleaning method for silicon surface using hydrogen fluoride gas and hydrogen chloride gas in a hydrogen ambient  

Microsoft Academic Search

To obtain a desirable silicon substrate surface for epitaxial growth, the in situ cleaning method is studied for the first time in a hydrogen ambient at atmospheric pressure in a quartz chamber using a combination of hydrogen fluoride gas and hydrogen chloride gas. A native oxide film can be removed by anhydrous hydrogen fluoride gas at room temperature within a

Hitoshi Habuka; Toru Otsuka; Masatake Katayama

1998-01-01

302

Evaporation/evapotranspiration estimates with remote sensing  

NASA Astrophysics Data System (ADS)

Evaporation is the transfer of water from a surface to the atmosphere. The evaporative process is intimately linked to the energy balance. In northern environments, the interactions between energy, land, and water can be different from those for more temperate regions. The application of any evapotranspiration model, with or without the use of remotely sensed data, to the northern environment requires that due consideration be given to those factors that become increasingly significant as one moves northward. For methods based on some reformulation of the energy balance, the inclusion and correct parameterization of the soil heat flux term is essential. The effect of the vegetation cover on the partitioning of energy to soil heat flux has been recognized and is demonstrated. Remote sensing of evaporation from water surfaces in northern regions suffers from two major deficiencies: (1) Relatively little is known about the evaporation regime of northern lakes; and (2) relatively little effort has been directed towards the development of remote sensing techniques for estimating evaporation from open water in general. For the estimation of lake evaporation, an improved understanding of the advective boundary layer over water is required. With respect to remote sensing of lake evaporation, although water surface temperatures are easily obtained in the absence of cloud cover, improved parameterization of ice formation and decay is required.

Granger, Raoul; Bussières, Normand

303

Evaporation of an atomic beam on a material surface  

SciTech Connect

We report on the implementation of evaporative cooling of a magnetically guided beam by adsorption on a ceramic surface. We use a transverse magnetic field to shift locally the beam towards the surface, where atoms are selectively evaporated. With a 5-mm-long ceramic piece, we gain a factor of 1.5{+-}0.2 on the phase-space density. Our results are consistent with a 100% efficiency of this evaporation process. The flexible implementation that we have demonstrated, combined with the very local action of the evaporation zone, makes this method particularly suited for the evaporative cooling of a beam.

Reinaudi, G.; Lahaye, T.; Couvert, A.; Wang, Z.; Guery-Odelin, D. [Laboratoire Kastler Brossel, 24 rue Lhomond, F-75231 Paris Cedex 05 (France)

2006-03-15

304

Asymptotic Behavior of Rotating Rarefied Gases with Evaporation and Condensation.  

National Technical Information Service (NTIS)

The asymptotic behavior of the cylindrical Couette flow problem for a rarefied rotating gas with evaporation and condensation is studied when the state of equilibrium is perturbed by the following small thermodynamic forces: (i) the pressure difference of...

L. M. Cumin G. M. Kremer F. Sharipov

2000-01-01

305

Evaporative cooling of magnetically trapped atomic molybdenum  

SciTech Connect

We have magnetically trapped and evaporatively cooled atomic molybdenum. Using a cryogenic helium buffer gas, 2x10{sup 10} molybdenum atoms are loaded into a magnetic trap at an initial temperature of 500 mK. The molybdenum atoms undergo two-body decay with a measured inelastic rate constant of g{sub in}=(1.2{+-}0.6)x10{sup -12} cm{sup 3} s{sup -1} for the initial conditions after loading. The molybdenum atoms are cooled by adiabatic expansion and forced evaporation to 200 mK.

Hancox, Cindy I.; Hummon, Matthew T.; Nguyen, Scott V.; Doyle, John M. [Department of Physics, Harvard University, Cambridge, Massachusetts 02138 (United States)

2005-03-01

306

Predicting evaporation rates and times for spills of chemical mixtures  

Microsoft Academic Search

Spreadsheet and short-cut methods have been developed for predicting evaporation rates and evaporation times for spills and constrained baths of chemical mixtures. Steady-state and time-varying predictions of evaporation rates can be made for six-component mixtures, including liquid-phase non-idealities as expressed through the UNIFAC method for activity coefficients. A group-contribution method is also used to estimate vapor-phase diffusion coef- ficients, which

RAYMOND L. SMITH

2001-01-01

307

Operating method for gas turbine with variable inlet vanes  

SciTech Connect

A method is described of operating a gas turbine engine having a centrifugal compressor which is driven by a high-pressure turbine, and wherein the centrifugal compressor is the only compressor of the engine, comprising the steps of: positioning a variable inlet guide vane at an inlet air passage of the centrifugal compressor for adjusting the air flow rate through the engine; and changing the orientation of the guide vane while keeping the speed of rotation of the engine at a high level near its rated value to control the output of the engine by controlling the air flow rate through the engine.

Morishita, Susumu; Miyake, Yoshiyaki; Uchida, Seishi.

1993-07-06

308

Experimental Method for Determination of the Rate of Evaporation of 2,4,6-Trinitrotoluene (TNT) and 2,4-Dinitrotoluene (2,4-DNT).  

National Technical Information Service (NTIS)

The rate of evaporation of 1,3,5-trinitrotoluene (TNT) and 2,4-dinitrotoluene (DNT) into air under ambient conditions was determined. This was accomplished by making cast pipes of TNT and 2,4-DNT. Nitrogen was passed through a pipe and then through a cold...

A. B. Rosencrance E. E. Brueggemann

1993-01-01

309

Films of brookite TiO2 nanorods/nanoparticles deposited by matrix-assisted pulsed laser evaporation as NO2 gas-sensing layers  

NASA Astrophysics Data System (ADS)

Titanium dioxide (TiO2) nanorods in the brookite phase, with average dimensions of 3-4 nm × 20-50 nm, were synthesized by a wet-chemical aminolysis route and used as precursors for thin films that were deposited by the matrix-assisted pulsed laser evaporation (MAPLE) technique. A nanorod solution in toluene (0.016 wt% TiO2) was frozen at the liquid-nitrogen temperature and irradiated with a KrF excimer laser at a fluence of 350 mJ/cm2 and repetition rate of 10 Hz. Single-crystal Si wafers, silica slides, carbon-coated Cu grids and alumina interdigitated slabs were used as substrates to allow performing different characterizations. Films fabricated with 6000 laser pulses had an average thickness of ˜150 nm, and a complete coverage of the selected substrate as achieved. High-resolution scanning and transmission electron microscopy investigations evidenced the formation of quite rough films incorporating individually distinguishable TiO2 nanorods and crystalline spherical nanoparticles with an average diameter of ˜13 nm. Spectrophotometric analysis showed high transparency through the UV-Vis spectral range. Promising resistive sensing responses to 1 ppm of NO2 mixed in dry air were obtained.

Caricato, A. P.; Buonsanti, R.; Catalano, M.; Cesaria, M.; Cozzoli, P. D.; Luches, A.; Manera, M. G.; Martino, M.; Taurino, A.; Rella, R.

2011-09-01

310

Applications of Electromagnetic Measurement Methods in Oil and Gas Industry  

NASA Astrophysics Data System (ADS)

When hydrocarbons accumulate in reservoirs, the reservoir rocks and a large volume of rock associated with the reservoirs undergo resistance changes. This method relates generally to the field of geophysical prospecting for the purposes of hydrocarbon exploration, development, and production. This method includes measuring magnetic field gradient in at least two orthogonal directions in response to the induced electromagnetic field and determining an electric field response. Specifically, this method is a method for determining the difference between the electrical resistance of a reservoir at an initial time and its electrical resistance at one or more later times, and relating that difference to production of hydrocarbons from the reservoir during the interim period. Electromagnetic methods are now being used to provide images of subsurface resistance on the reservoir scale. These images provide for the first time observation of the distribution of porosity and fluid content on the same scale as the reservoir. They are being used to identify bypassed oil, monitor sweep efficiency, identify unanticipated breakthrough, and map features. All such information could previously only be inferred from measurements within the well or from production data from the well. For monitoring production and enhanced recovery processes, when it can be assumed that the porosity is essentially constant and when there is a resistivity contrast in the different fluids or phases involved, the imaged resistivity is a direct mapping of the changes in saturation. In this paper we discuss about the methods for electromagnetic measurement methods and its application in oil and gas industry.

Dehghani, Maryam

2011-12-01

311

Multicomponent droplet heating and evaporation: Numerical simulation versus experimental data  

Microsoft Academic Search

The earlier reported simplified model for multi-component droplet heating and evaporation is generalised to take into account the coupling between droplets and the ambient gas. The effects of interaction between droplets are also considered. The size of the gas volume, where the interaction between droplets and gas needs to be taken into account, is estimated based on the characteristic thermal

S. S. Sazhin; A. E. Elwardany; P. A. Krutitskii; V. Deprédurand; G. Castanet; F. Lemoine; E. M. Sazhina; M. R. Heikal

2011-01-01

312

A New Technique Keeping off the Mn Evaporant from Oxygen Atmosphere during Reactive Evaporation Process  

NASA Astrophysics Data System (ADS)

Manganese oxide films for lithium secondary batteries were prepared using a reactive evaporation method. The Mn metal in the crucible suffers severe oxidation during the reactive evaporation process, which deteriorates it’s deposition rate with increasing deposition run. It is also difficult to maintain the stoichiometry of films from run to run. This paper shows a new technique which keeps off the Mn evaporant from oxygen atmosphere during the reactive evaporation process. To achieve it a stainless steel cell has been installed in the bottom of the Mn crucible, which can successfully isolate Mn evaporant from incoming oxygen atoms. It improves the reproducibility of film composition because of stabilizing of the deposition rate.

Isai, Masaaki; Shimada, Takeyoshi; Matsui, Takaaki; Fujiyasu, Hiroshi

2001-08-01

313

Study on Turbulent Modeling in Gas Entrainment Evaluation Method  

NASA Astrophysics Data System (ADS)

Suppression of gas entrainment (GE) phenomena caused by free surface vortices are very important to establish an economically superior design of the sodium-cooled fast reactor in Japan (JSFR). However, due to the non-linearity and/or locality of the GE phenomena, it is not easy to evaluate the occurrences of the GE phenomena accurately. In other words, the onset condition of the GE phenomena in the JSFR is not predicted easily based on scaled-model and/or partial-model experiments. Therefore, the authors are developing a CFD-based evaluation method in which the non-linearity and locality of the GE phenomena can be considered. In the evaluation method, macroscopic vortex parameters, e.g. circulation, are determined by three-dimensional CFD and then, GE-related parameters, e.g. gas core (GC) length, are calculated by using the Burgers vortex model. This procedure is efficient to evaluate the GE phenomena in the JSFR. However, it is well known that the Burgers vortex model tends to overestimate the GC length due to the lack of considerations on some physical mechanisms. Therefore, in this study, the authors develop a turbulent vortex model to evaluate the GE phenomena more accurately. Then, the improved GE evaluation method with the turbulent viscosity model is validated by analyzing the GC lengths observed in a simple experiment. The evaluation results show that the GC lengths analyzed by the improved method are shorter in comparison to the original method, and give better agreement with the experimental data.

Ito, Kei; Ohshima, Hiroyuki; Nakamine, Yoshiaki; Imai, Yasutomo

314

Quantitative analysis of polyvinyl alcohol on the surface of poly( d, l-lactide-co-glycolide) microparticles prepared by solvent evaporation method: effect of particle size and PVA concentration  

Microsoft Academic Search

Polyvinyl alcohol (PVA) is an emulsion stabilizer that is used in the solvent evaporation method for poly(d,l-lactide-co-glycolide) (PLG) microparticles preparation. In this study, the surface binding of PVA on PLG microparticles was quantitatively examined by employing gel permeation chromatography. The PVA binding can affect hydrophobicity and digestibility of the microparticle surface. GPC analysis detected the presence of PVA bound on

Seung Chan Lee; Jae Taek Oh; Myoung Ho Jang; Soo Il Chung

1999-01-01

315

Electrical Transport Properties of Nb-DOPED SrTiO3 Fabricated on MgO(100) and SrTiO3(100) Substrates by Reactive Evaporation Method  

Microsoft Academic Search

Undoped and Nb-doped SrTiO3 films have been fabricated on SrTiO3(100) and MgO(100) substrates at temperatures between 500°C and 800°C by a reactive evaporation method. The single-crystallinity of these films was confirmed by X-ray diffraction and RHEED studies. Better crystallinity was obtained for films fabricated at substrate temperatures of 700°C and 800°C. Metallic behavior was found in the resistivity vs. temperature

M. Nagata; Y. Mizuno; H. Nojima; K. Sugawara; M. Koba

1993-01-01

316

Maintenance strategy for a salt gradient solar pond coupled with an evaporation pond  

Microsoft Academic Search

In a previous study, the authors presented a simple mathematical model for predicting the ratio of the evaporation pond area to that of a salt gradient solar pond area. The evaporation pond idea provides a very attractive method of salt recycling by evaporation, especially in areas of high evaporation and low rates of rain as it is the case for

K. R. Agha; S. M. Abughres; A. M. Ramadan

2004-01-01

317

Analysis of evaporation in laser welding  

NASA Astrophysics Data System (ADS)

The evaporation process in CO2 laser welding was analyzed experimentally on the basis of evaporation and soot deposition rates, light scattering and plasma behavior. Heavier shielding gas results in more soot deposition by carrying the condensed particles to the work surface. At power density, 2-3 x 10(exp 5) W/sq cm), which is just below the critical value for deep penetration welding, the soot deposition becomes heaviest with accompanying violent fluctuation of the light emission of the plasma. A hypothetical mechanism of the soot deposition is proposed; at 2-3 x 10(exp 5) W/sq cm, the molten pool surface is hemispherically depressed by the recoil force of evaporation, and acts like a concave mirror to refocus the reflected laser beam within the plasma plume to heat it up. The adiabatic expansion of the plasma caused by the molten pool motion plays an important role to condense the vapor into the soot.

Miyamoto, Isamu

1995-04-01

318

Diagnostics of an RF Plasma Flash Evaporation Process Using the Monochromatic Imaging Technique  

Microsoft Academic Search

The high densities and high gas temperature of rf plasmas at pressures near 1 atm are favorable for the development of plasma sources capable of evaporating solid precursors in the plasma zone. In the cooler region downstream of the plasma, the evaporated material condenses to nanoparticles and\\/or coatings. The complete evaporation of precursors injected into a thermal plasma depends on

P. Buchner; H. Schubert; J. Uhlenbusch; M. Weiss

2001-01-01

319

How do drops evaporate?  

NASA Astrophysics Data System (ADS)

The problem of evaporating drops with non-pinned contact line, although seemingly trivial, so far lacks satisfactory theoretical description. In particular, there has been much discussion regarding appropriate evaporative mass flux model. We make an attempt to resolve this issue by comparing our experimental data with the results of several mathematical models for evaporating drops. After describing experimental procedure, we propose several models for mass flux and develop a governing equation for evolution of drop's thickness. Two-dimensional numerical results are then compared to the experimental results, and the most appropriate mass flux model is identified. Finally, we propose the governing equation for the full 3D system and present some new numerical results related to curious phenomena, where so-called ``octopus-shaped'' instabilities appear ahead of the contact line of volatile dropsootnotetextY. Gotkis, I. Ivanov, N. Murisic, L. Kondic, Phys. Rev. Lett. 97, 186101 (2006)..

Murisic, Nebojsa; Kondic, Lou

2007-11-01

320

Evaporatively driven morphological instability.  

PubMed

Simple observations of evaporating solutions reveal a complex hierarchy of spatiotemporal instabilities. We analyze one such instability suggested by the qualitative observations of Du and Stone and find that it is driven by a variant of the classical morphological instability in alloy solidification. In the latter case a moving solid-liquid interface is accompanied by a solutally enriched boundary layer that is thermodynamically metastable due to constitutional supercooling. Here, we consider the evaporation of an impure film adjacent to a solid composed of the nonvolatile species. In this case, constitutional supercooling within the film is created by evaporation at the solution-vapor interface and this drives the corrugation of the solid-solution interface across the thickness of the film. The principal points of this simple theoretical study are to suggest an instability mechanism that is likely operative across a broad range of technological and natural systems and to focus future quantitative experimental searches. PMID:17677459

Style, Robert W; Wettlaufer, J S

2007-07-16

321

Total introduction of microsamples in inductively coupled plasma mass spectrometry by high-temperature evaporation chamber with a sheathing gas stream.  

PubMed

A systematic study on the high-temperature Torch Integrated Sample Introduction System (TISIS) for use in Inductively Coupled Plasma Mass Spectrometry (ICP-MS) has been performed. The investigation included the optimization of the relevant parameters (chamber temperature, sheathing gas flow rate, nebulizer gas flow rate, sample uptake rate), the evaluation of its performance characteristics (sensitivity, limits of detection, stability, memory effects, use with the dynamic reaction cell) and representative applications to environmental, biological and clinical samples. Under the optimal conditions (T=150°C; nebulizer gas flow rate of 0.7Lmin(-1) along with sheathing gas flow rate of 0.35Lmin(-1) and a sample uptake rate of 20?Lmin(-1)), the sensitivity was from 2 to 8 times higher than that measured using a conventional micronebulizer/mini-spray chamber system, due to the enhanced analyte mass transport toward the plasma and the solvent introduction in the vapour form. In addition, for several elements, TISIS provided lower limits of detection than the conventional system, even when the latter worked at 5-fold higher sample uptake rate. Short-term and long-term precision was better than 5%. Spectroscopic interferences arising from common matrices were efficiently removed by the dynamic reaction cell technique. The application of TISIS/ICP-MS to representative certified reference samples (spinach leaves, marine plankton, bone tissue, human blood) proved the suitability of this system for the accurate analysis of limited-size samples. PMID:23452782

Grotti, Marco; Ardini, Francisco; Todolì, Josè Luis

2013-01-17

322

Apparatus and method for monitoring of gas having stable isotopes  

DOEpatents

Gas having stable isotopes is monitored continuously by using a system that sends a modulated laser beam to the gas and collects and transmits the light not absorbed by the gas to a detector. Gas from geological storage, or from the atmosphere can be monitored continuously without collecting samples and transporting them to a lab.

Clegg, Samuel M; Fessenden-Rahn, Julianna E

2013-03-05

323

Hot air drum evaporator  

DOEpatents

An evaporation system for aqueous radioactive waste uses standard 30 and 55 gallon drums. Waste solutions form cascading water sprays as they pass over a number of trays arranged in a vertical stack within a drum. Hot dry air is circulated radially of the drum through the water sprays thereby removing water vapor. The system is encased in concrete to prevent exposure to radioactivity. The use of standard 30 and 55 gallon drums permits an inexpensive compact modular design that is readily disposable, thus eliminating maintenance and radiation build-up problems encountered with conventional evaporation systems.

Black, Roger L. (Idaho Falls, ID)

1981-01-01

324

Method of treating exhaust gas discharged from nitric acid plant  

Microsoft Academic Search

A compressed exhaust gas containing nitrogen oxides discharged from a compressed absorption-type nitric acid plant is treated by adding ammonia or an ammonia precursor to the gas. The gas is passed through a NO\\/sub x\\/-removing catalytic layer to an exhaust gas turbine wherein the temperature of the main flow of the exhaust gas in the zone from the point of

K. Takami; S. Abe; Y. Takigawa; T. Tsutsumi; Y. Kinsho

1978-01-01

325

Glow discharge simulation of argon gas based on PIC-MCC method  

Microsoft Academic Search

Gas discharge is an important phenomenon in high voltage gas insulation. A new method PIC-MCC is used here to study the glow discharge of argon gas in low pressure. A microscopic model is established in our work and numbers of charged particles were traced by particle in cell (PIC) method. Different from other PIC methods, the collisions between electron, ion

Li Jing; Cao Yundong; Yu Longbin; Liu Xiaoming; Wu Wei

2009-01-01

326

DEFROSTING THE FIN TUBE EVAPORATORS OF AIR\\/WATER HEAT PUMPS USING AMBIENT AIR  

Microsoft Academic Search

Air\\/water heat pumps for heating systems are becoming increasingly popular. A major challenge for these systems is the formation of ice and frost in the fin-tube evaporator. Defrosting is usually accomplished by the reverse-cycle or hot-gas defrosting technique. In both defrosting modes, the compressor is in operation. An alternative method is ambient-air defrosting, where the heat pump's compressor is simply

B. Wellig; M. Imholz; M. Albert; K. Hilfiker

327

Localization of shallow gas deposits and uncontrolled gas flows in young and unconsolidated sediments by geophysical methods  

SciTech Connect

The great mass of Neogene sediments in the Hungarian basin, where several hydrocarbon accumulations are known, is affected by Pliocene strike-slip movements, resulting in many [open quotes]flower structures.[close quotes] The gas may migrate from the reservoirs upward to the surface along the faults. Thus, shallow gas deposits can be located in the young, unconsolidated sands. There are also several shallow gas deposits derived from uncontrolled gas flows. In Hungary, the shallow gas reservoirs, which are small but increasingly important, have not yet been explored properly. However, the depleting gas may pollute the water in the soil as well as cause explosions. Our purpose is to develop inexpensive, complete, and highly sophisticated field- and data-processing techniques and an integrated complex of geophysical methods in order to define the limits of shallow gas deposits. To avoid anomalous behavior on seismic sections of the depleting gas, we started from uncontrolled gas flows which require special velocity and amplitude vs. offset analyses. In addition, natural and controlled source electromagnetic/electric surveys with various parameters were applied. An industrial-scale seismic section over an uncontrolled gas flow, special sections over flower structures and geoelectric sections, and a magnetic map are presented. The integrated complex of geophysical methods outlined above is being developed in order to establish the conditions for the exploration of gas reservoirs which have been used close to their locality and which could be recovered inexpensively.

Csoergei, J.; Kummer, I.; Papa, A.; Sipos, J.; Solyom, I.; Takacs, E.; Timar, Z. (Eotvos Lorand Geophysical Institute of Hungary, Budapest (Hungary)); Keresztes, T. (MOL RT, Budapest (Hungary))

1993-09-01

328

Method for flue gas conditioning with the decomposition products of ammonium sulfate or ammonium bisulfate  

Microsoft Academic Search

This patent describes a method for conditioning flue gas containing suspended fly ash. It comprises: diverting a slipstream of flue gas from a main flue gas stream at a point upstream from an air preheater located directly upstream of an electrostatic precipitator; introducing an aqueous solution of ammonium sulfate or ammonium bisulfate into the diverted flue gas slipstream thereby effecting

R. F. Altman; J. P. Gooch; E. B. Dismukes; E. C. Jr. Landham

1989-01-01

329

A Gas Chromatographic Method for the Determination of Aldose and Uronic Acid Constituents of Plant Cell Wall Polysaccharides 1  

PubMed Central

A major problem in determining the composition of plant cell wall polysaccharides has been the lack of a suitable method for accurately determining the amounts of galacturonic and glucuronic acids in such polymers. A gas chromatographic method for aldose analysis has been extended to include uronic acids. Cell wall polysaccharides are depolymerized by acid hydrolysis followed by treatment with a mixture of fungal polysaccharide-degrading enzymes. The aldoses and uronic acids released by this treatment are then reduced with NaBH4 to alditols and aldonic acids, respectively. The aldonic acids are separated from the alditols with Dowex-1 (acetate form) ion exchange resin, which binds the aldonic acids. The alditols, which do not bind, are washed from the resin and then acetylated with acetic anhydride to form the alditol acetate derivatives. The aldonic acids are eluted from the resin with HCl. After the resin has been removed, the HCl solution of the aldonic acids is evaporated to dryness, converting the aldonic acids to aldonolactones. The aldonolactones are reduced with NaBH4 to the corresponding alditols, dried and acetylated. The resulting alditol acetate mixtures produced from the aldoses and those from the uronic acids are analyzed separately by gas chromatography. This technique has been used to determine the changes in composition of Red Kidney bean (Phaseolus vulgaris) hypocotyl cell walls during growth, and to compare the cell wall polysaccharide compositions of several parts of bean plants. Galacturonic acid is found to be a major component of all the cell wall polysaccharides examined.

Jones, Thomas M.; Albersheim, Peter

1972-01-01

330

Solvent Evaporation Rates  

Microsoft Academic Search

A system of equations for predicting the evaporation rates of solvents is presented. These equations may be used by the industrial hygienist, in conjunction with the diffusion equations developed elsewhere, to predict the atmospheric concentrations of vapors from spilled toxic liquids. The equations are derived from wind tunnel tests and applied to predictions for spills both indoors and outdoors.

DOUGLAS C. GRAY

1974-01-01

331

Evaporation of extrasolar planets  

Microsoft Academic Search

This article presents a review on the observations and theoretical modeling of the evaporation of extrasolar planets. The observations and the resulting constraints on the upper atmosphere (thermosphere and exosphere) of the ``hot-Jupiters'' are described. The early observations of the first discovered transiting extrasolar planet, HD209458b, allowed the discovery that this planet has an extended atmosphere of escaping hydrogen. Subsequent

A. Lecavelier Des Etangs

2010-01-01

332

Microscale Evaporation Heat Transfer  

Microsoft Academic Search

In this work, microscale evaporation heat transfer and capillary phenomena for ultra thin liquid film area are presented. The interface shapes of curved liquid film in rectangular minichannel and in vicinity of liquid-vapor-solid contact line are determined by a numerical solution of simplified conduction through liquid layer. The data of numerical calculation of local heat transfer in rectangular channel and

V. V. Kuznetsov; S. A. Safonov

333

Estimation of evaporation from the Dead Sea  

NASA Astrophysics Data System (ADS)

A project to link the Dead Sea to the Red Sea via a canal is undergoing extensive study. As part of this study, a method to estimate evaporation from the Dead Sea is required as it is a hypersaline lake in which standard methods cannot be applied. Two methods based on Penman and Dalton formulae were examined. The method derived here is a modified Penman model that estimates the evaporation as a function of salinity, humidity, air temperature and wind speed. Other parameters such as water temperature are included implicitly in the model. The results obtained were verified as satisfactory agreement was achieved by comparison with previous measurements. A short-cut relationship to estimate evaporation as a function of salinity only was also derived.

Asmar, B. N.; Ergenzinger, Peter

1999-12-01

334

Method for removing metal vapor from gas streams  

DOEpatents

A process for cleaning an inert gas contaminated with a metallic vapor, such as cadmium, involves withdrawing gas containing the metallic contaminant from a gas atmosphere of high purity argon; passing the gas containing the metallic contaminant to a mass transfer unit having a plurality of hot gas channels separated by a plurality of coolant gas channels; cooling the contaminated gas as it flows upward through the mass transfer unit to cause contaminated gas vapor to condense on the gas channel walls; regenerating the gas channels of the mass transfer unit; and, returning the cleaned gas to the gas atmosphere of high purity argon. The condensing of the contaminant-containing vapor occurs while suppressing contaminant particulate formation, and is promoted by providing a sufficient amount of surface area in the mass transfer unit to cause the vapor to condense and relieve supersaturation buildup such that contaminant particulates are not formed. Condensation of the contaminant is prevented on supply and return lines in which the contaminant containing gas is withdrawn and returned from and to the electrorefiner and mass transfer unit by heating and insulating the supply and return lines. 13 figs.

Ahluwalia, R.K.; Im, K.H.

1996-04-02

335

Gas chromatographic method for measuring nitrogen dioxide and peroxyacetyl nitrate in air without compressed gas cylinders  

Microsoft Academic Search

A gas chromatographic technique that measures atmospheric concentrations of peroxyacetyl nitrate (PAN) and NOâ has been developed that uses luminol-based chemiluminescence for detection. The carrier gas is air that has been scrubbed by passing it over FeSOâ, which eliminates the need for any compressed gas cylinders. A novel gas sampling system and time enable variable sample volumes of contaminated air

Mark R. Burkhardt; Nyengenya I. Maniga; Donald H. Stedman; Richard J. Paur

1988-01-01

336

CaO-MgO-Al 2o 3SiO 2 liquids: chemical and isotopic effects of Mg and Si evaporation in a closed system of solar composition  

Microsoft Academic Search

A method is shown for calculating vapor pressures over a CMAS droplet in a gas of any composition. It is applied to the problem of the evolution of the chemical and Mg and Si isotopic composition of a completely molten droplet having the composition of a likely refractory inclusion precursor during its evaporation into the complementary, i.e. modified solar, gas

L. Grossman; A. V. Fedkin

2003-01-01

337

Some methods of oil and gas reserve estimation in Azerbaijan  

SciTech Connect

This article deals with the scientific and practical problems related to estimating oil and gas reserves in terrigenous reservoirs of the Productive Series of middle Pliocene and in Upper Cretaceous volcanic and sedimentary rocks. The deposits in question are spread over onshore Azerbaijan and adjacent offshore areas in the Caspian Sea and are approximately 6.5 km deep. This article presents lithologic, stratigraphic, and petrophysical criteria used for selecting prospects for reserve estimation. Also presented are information on structure of rocks and estimation of their lithologic and physical properties. New methods for the interpretation and application of petrophysical and logging data, as well as statistical estimation of reserves, in complex volcaniclastic reservoir rocks, are also discussed.

Abasov, M.T.; Buryakovsky, L.A.; Kondrushkin, Y.M.; Dzhevanshir, R.D.; Bagarov, T.Y. [Azerbaijan Academy of Sciences, Baku (Azerbaijan); Chilingar, G.V. [Univ. of Southern California, Los Angeles, CA (United States). Dept. of Civil and Environmental Engineering

1997-08-01

338

Method for removal of sulfur compounds from a gas  

SciTech Connect

This invention relates to a process for the removal of sulfur compounds from a gas stream which consists of contacting said gas stream with alkali metal salts of sulfonamides or resins containing sulfonamide functionalities.

Frech, K.J.; Tazuma, J.J.

1981-08-11

339

Gas-liquid separator and method of operation  

DOEpatents

A system for gas-liquid separation in electrolysis processes is provided. The system includes a first compartment having a liquid carrier including a first gas therein and a second compartment having the liquid carrier including a second gas therein. The system also includes a gas-liquid separator fluidically coupled to the first and second compartments for separating the liquid carrier from the first and second gases.

Soloveichik, Grigorii Lev (Latham, NY); Whitt, David Brandon (Albany, NY)

2009-07-14

340

Visualization of the evaporation of a diesel spray using combined Mie and Rayleigh scattering techniques  

NASA Astrophysics Data System (ADS)

Evaporating Diesel sprays are studied by laser Rayleigh scattering measurements in an optically accessible high-pressure/high-temperature cell that reproduces the thermodynamic conditions which exist in the combustion chamber of a Diesel engine during injection. n-Decane is injected into the vessel using a state-of-the-art near-production three-hole nozzle. Global images of the distributions of the liquid and vapor phases of the injected fuel are obtained using a combined Schlieren and Mie scattering setup. More details about the evaporation are revealed when the spray is illuminated by a laser light sheet: laser light can be scattered by molecules in the gas phase (Rayleigh scattering) or comparably large fuel droplets (Mie scattering). The former is seen in regions where the fuel has completely evaporated, and the latter is dominant in regions with high droplet concentrations. Studying the polarization of the signal light allows the distinction of three different regions in the spray that are characterized by a moderate, low or negligible concentration of liquid fuel droplets. The characteristics of fuel evaporation are investigated for different observation times after the start of injection, chamber conditions and injection pressures. For the quantification of the fuel concentration measurements based on Rayleigh scattering, a calibration method that uses propane as a reference gas is presented and tested. At high ambient temperatures, the accuracy of the concentration measurements is limited by pyrolysis of the fuel molecules.

Adam, Anne; Leick, Philippe; Bittlinger, Gerd; Schulz, Christof

2009-09-01

341

Method and apparatus for producing natural gas from tight formations  

Microsoft Academic Search

Natural gas wells in a tight formation area are drilled and completed with piping, the piping being capped with a Christmas tree. The piping is then utilized as a reservoir to collect natural gas from the tight formation over a prolonged time period. Mobile pressure vessel units are employed periodically to recover the collected natural gas, on a schedule designed

D. A. Bresie; J. M. Burns; D. W. Fowler

1984-01-01

342

How Does Evaporation Occur From Sphagnum Mosses?  

NASA Astrophysics Data System (ADS)

How does evaporation occur from Sphagnum mosses? What are the contributions of liquid and vapour flux within the moss architecture to the flux from it? What is the evaporating surface? The poor understanding of these processes limits our ability to predict evaporation from, or the moisture distribution within, moss communities. To address this we measured evaporation (average 1.9 mm/d) from laboratory columns of "undisturbed" Sphagnum moss samples having a constant water table 20 cm below the surface being supplied with water from a common (isotopic) source. We then assessed the nature and magnitude of water fluxes by analyzing depth profiles of volumetric water content (VMC), relative humidity (RH) of pore gas, isotopic composition of pore water and related soil properties. VMC in the upper 15 cm was quite uniform averaging 13.6%, increasing to 25.9% at 20-25 cm, then saturation below. RH was 94% at 2.5 cm depth, progressively approaching 100% at 15 cm depth. Relative to oxygen-18 and deuteium of source water (-13.1 and -86.7 permil, respectively) enrichment was greatest in the 0-5 cm layer (average -6.57 and -61.10 permil, respectively), and decreased with depth. Corresponding oxygen- 18 and deuterium values clustered tightly along a common evaporation line having a slope of 3.76, as predicted for free water evaporation under the same experimental conditions. Given the vapour pressure deficit (RH<100%) in pore gases, and the resulting isotopic fractionation, it is apparent that latent heat exchange (vaporization) occurs 5 to 10 cm below the upper surface. However, the diffusive vapor flux based on Fick's law was estimated to be only 0.02-0.04 mm/d, or about 2% of the total evaporative flux from the community surface. Modeling of the isotope enrichment profiles assuming negligible net vapor-phase transport also yielded remarkably close agreement with measured mass flux from the columns, confirming that liquid flow within the profile is the dominant form of water transport. These results suggest that incorporation of water- isotope sampling into field studies may allow improved quantification of evaporation from natural moss communities, including the possibility of partitioning evaporative and transpirative fluxes in Sphagnum dominated peatlands colonized also by vascular plants.

Price, J. S.; Whittington, P. N.; Yi, Y.; Edwards, T. W.

2006-12-01

343

Method of jointly manufacturing carburetted water gas and volatile hydrocarbon motor fuels  

Microsoft Academic Search

This patent describes a method method of jointly manufacturing carburetted water gas and volatile hydrocarbon motor fuel by air blasting a bed of carbonaceous fuel to incandescence. It involves passing the heated blast gases as produced over heat-absorbent material to heat the same, steam blasting the incandescent bed to produce water gas, passing the heated water gas over the said

1926-01-01

344

Oil shale process water evaporation  

SciTech Connect

The primary objectives of this research program were to study chemical, microclimatological, and interactive effects on the evaporation of low-quality oil shale process wastewaters to develop more applicable evaporation models and evaporation design criteria for the disposal of oil shale process waters and to analyze the processes associated with the release of potentially toxic emissions from these low-quality effluents. The research program incorporated field and laboratory studies analyzing microclimatic and chemical effects on the evaporation of oil shale process wastewaters. Field studies at Laramie, Wyoming were designed to continuously monitor microclimatological conditions and the evaporation from three low-quality effluents using Class A evaporation pans. Fresh water evaporation was monitored as a control. Process waters were routinely monitored for concentrations of organic and inorganic constituents. Laboratory studies were designed to isolate and describe significant climatic, chemical, and interactive effects on evaporation rates. Results from the above studies were utilized to develop a regression model to predict evaporation from these low quality effluents. This model was then compared to commonly utilized models to estimate evaporation. A stochastic model was developed using a first order markov process to generate 1000 20-year climatological records. Mass balance techniques were then used to evaluate the new data sets for evaporation processes and determine critical design parameters for evaporation disposal ponds. Laboratory studies were conducted to determine significant effects on the Henry's Law Constant for eight organic compounds in two process waters. 69 refs., 16 figs., 51 tabs.

Hasfurther, V.R.; Reeves, T.

1990-01-01

345

Methods of Off-Gas Flammability Control for DWPF Melter Off-Gas System at Savannah River Site.  

National Technical Information Service (NTIS)

Several key operating variables affecting off-gas flammability in a slurry-fed radioactive waste glass melter are discussed, and the methods used to prevent potential off-gas flammability are presented. Two models have played a central role in developing ...

A. S. Choi D. C. Iverson

1996-01-01

346

Evolutionary neural networks for monthly pan evaporation modeling  

NASA Astrophysics Data System (ADS)

Evolutionary neural networks (ENN) is used for modeling pan evaporation.Data from two stations of Turkey are used in the study.ENN models are compared with fuzzy genetic, neuro-fuzzy and ANN methods.ENN models perform better than the other models.Pan evaporation can be successfully estimated by the ENN method.

Ki?i, Özgür

2013-08-01

347

DWPF Recycle Evaporator Shielded Cells Testing  

SciTech Connect

Testing was performed to determine the feasibility and processing characteristics of evaporation of actual Defense Waste Processing Facility (DWPF) recycle material. Samples of the Off Gas Condensate Tank (OGCT) and Slurry Mix Evaporator Condensate Tank (SMECT) were transferred from DWPF to the Savannah River National Lab (SRNL) Shielded Cells and blended with De-Ionized (DI) water and a small amount of Slurry Mix Evaporator (SME) product. A total of 3000 mL of this feed was concentrated to approximately 90 mL during a semi-batch evaporation test of approximately 17 hours. One interruption occurred during the run when the feed tube developed a split and was replaced. Samples of the resulting condensate and concentrate were collected and analyzed. The resulting analysis of the condensate was compared to the Waste Acceptance Criteria (WAC) limits for the F/H Effluent Treatment Plant (ETP). Results from the test were compared to previous testing using simulants and OLI modeling. Conclusions from this work included the following: (1) The evaporation of DWPF recycle to achieve a 30X concentration factor was successfully demonstrated. The feed blend of OGCT and SMECT material was concentrated from 3000 mL to approximately 90 mL during testing, a concentration of approximately 33X. (2) Foaming was observed during the run. Dow Corning 2210 antifoam was added seven times throughout the run at 100 parts per million (ppm) per addition. The addition of this antifoam was very effective in reducing the foam level, but the impact diminished over time and additional antifoam was required every 2 to 3 hours during the run. (3) No scale or solids formed on the evaporator vessel, but splatter was observed in the headspace of the evaporator vessel. No scaling formed on the stainless steel thermocouple. (4) The majority of the analytes met the F/H ETP WAC. However, the detection limits for selected species (Sr-90, Pu-238, Pu-240, Am-243, and Cm-244) exceeded the ETP WAC limits. (5) I-129 was calculated to have exceeded the ETP WAC limits based on an assumed Decontamination Factor (DF) of 1 during evaporation. (6) The DF for most species was limited by the detection limits of the sample analysis. Based on iron, manganese, total alpha, total beta, and other species, very low entrainment was noted and evaporator DF was >10,000 for non-volatile species. (7) Very low DF's were obtained for selected species, especially mercury and formate. These species are present as volatile compounds and will exceed ETP WAC limits if sufficient concentrations are in the evaporator feed. (8) The evaporator DF's for the radioactive test were in good agreement with simulant test results. Differences noted in the DF of selected species, such as Hg, were more likely attributed to analytical issues than differences in the performance of the two evaporators. (9) The simulant appeared to be conservative in terms of foaming and scaling characteristics of the evaporator. The initial spike in foaming that occurred during all simulant runs did not occur during the Shielded Cells run and overall foaminess after the start of the test was controlled by antifoam additions. The splatter that was deposited during the radioactive test was less than the simulant runs and was more easily removed. (10) The OLI model results were overly conservative due to the manner that entrainment of solids was incorporated into the model.

Fellinger, T. L.; Herman, D. T.; Stone, M.E

2005-07-01

348

Molecular characterization of phospholipids by high-performance liquid chromatography combined with an evaporative light scattering detector, high-performance liquid chromatography combined with mass spectrometry, and gas chromatography combined with a flame ionization detector in different oat varieties.  

PubMed

Oat (Avena sativa L.) is an important crop produced in various regions of Europe and North America. Oat lipids are a heterogeneous mixture of acyl lipids and unsaponifiable components. The neutral lipids are mainly triacylglycerols and account for 50-60% of total oat lipids. Oat oil is also rich in polar lipids, that is, phospholipids and glycolipids. Characterization of oat polar lipids has largely been performed by thin-layer chromatography (TLC), but the composition of phospholipid classes has been poorly studied. The aim of our work was the determination of different phospholipids in Romanian oat samples. For that purpose, one commercial sample (Comun) and four pure varieties (Jeremy, Lovrin 1, Lovrin 27-T, and Mures) were used. High-performance liquid chromatography combined with an evaporative light scattering detector results allowed us to establish that phosphatidylethanolamine was the most representative phospholipid in all of the oat samples. In addition, high-performance liquid chromatography combined with electrospray ionization mass spectrometry analysis showed that C16:0, C16:1, C18:0, C18:1, C18:2, C18:3, C20:0, and C20:1 were the fatty acids bound to the glycerol backbone. Using first-preparative TLC and later gas chromatography, it was demonstrated that linoleic acid (C18:2) was the main fatty acid of the phospholipid fraction in all of the samples. PMID:23061991

Montealegre, Cristina; Verardo, Vito; Gómez-Caravaca, Ana Maria; García-Ruiz, Carmen; Marina, María Luisa; Caboni, Maria Fiorenza

2012-10-25

349

Evaporation of extrasolar planets  

NASA Astrophysics Data System (ADS)

This article presents a review on the observations and theoretical modeling of the evaporation of extrasolar planets. The observations and the resulting constraints on the upper atmosphere (thermosphere and exosphere) of the ``hot-Jupiters'' are described. The early observations of the first discovered transiting extrasolar planet, HD209458b, allowed the discovery that this planet has an extended atmosphere of escaping hydrogen. Subsequent observations showed the presence of oxygen and carbon at very high altitude. These observations give unique constraints on the escape rate and mechanism in the atmosphere of hot-Jupiters. The most recent Lyman-alpha HST observations of HD189733b and MgII observations of Wasp-12b allow for the first time a comparison of the evaporation from different planets in different environments. Models to quantify the escape rate from the measured occultation depths, and an energy diagram to describe the evaporation state of hot-Jupiters are presented. Using this diagram, it is shown that few already known planets like GJ876d or CoRot-7b could be remnants of formerly giant planets.

Lecavelier Des Etangs, A.

2010-12-01

350

Tried and True: Evaporating is cool  

NSDL National Science Digital Library

Many students hold misconceptions about evaporation. In this short exercise, students will apply the kinetic molecular theory to explain how cold water can evaporate and to observe the cooling effect of evaporation, and develop their own evaporation experiments.

Hand, Richard

2006-03-01

351

Systems and method for delivering liquified gas to an engine  

DOEpatents

A liquified gas delivery system for a motorized platform includes a holding tank configured to receive liquified gas. A first conduit extends from a vapor holding portion of the tank to a valve device. A second conduit extends from a liquid holding portion of the tank to the valve device. Fluid coupled to the valve device is a vaporizer which is in communication with an engine. The valve device selectively withdraws either liquified gas or liquified gas vapor from the tank depending on the pressure within the vapor holding portion of the tank. Various configurations of the delivery system can be utilized for pressurizing the tank during operation.

Bingham, Dennis N. (Idaho Falls, ID); Wilding, Bruce M. (Idaho Falls, ID); O' Brien, James E. (Idaho Falls, ID); Siahpush, Ali S. (Idaho Falls, ID); Brown, Kevin B. (Idaho Falls, ID)

2002-01-01

352

Methods For Delivering Liquified Gas To An Engine  

DOEpatents

A liquified gas delivery system for a motorized platform includes a holding tank configured to receive liquified gas. A first conduit extends from a vapor holding portion of the tank to a valve device. A second conduit extends from a liquid holding portion of the tank to the valve device. Fluid coupled to the valve device is a vaporizer which is in communication with an engine. The valve device selectively withdraws either liquified gas or liquified gas vapor from the tank depending on the pressure within the vapor holding portion of the tank. Various configurations of the delivery system can be utilized for pressurizing the tank during operation.

Bingham, Dennis N. (Idaho Falls, ID); Wilding, Bruce M. (Idaho Falls, ID); O' Brien, James E. (Idaho Falls, ID); Siahpush, Ali S. (Idaho Falls, ID); Brown, Kevin B. (Idaho Falls, ID)

2003-09-16

353

Methods For Delivering Liquified Gas To An Engine  

DOEpatents

A liquified gas delivery system for a motorized platform includes a holding tank configured to receive liquified gas. A first conduit extends from a vapor holding portion of the tank to a valve device. A second conduit extends from a liquid holding portion of the tank to the valve device. Fluid coupled to the valve device is a vaporizer which is in communication with an engine. The valve device selectively withdraws either liquified gas or liquified gas vapor from the tank depending on the pressure within the vapor holding portion of the tank. Various configurations of the delivery system can be utilized for pressurizing the tank during operation.

Bingham, Dennis N. (Idaho Falls, ID); Wilding, Bruce M. (Idaho Falls, ID); O' Brien, James E. (Idaho Falls, ID); Siahpush, Ali S. (Idaho Falls, ID); Brown, Kevin B. (Idaho Falls, ID)

2005-10-11

354

Method for high temperature mercury capture from gas streams  

DOEpatents

A process to facilitate mercury extraction from high temperature flue/fuel gas via the use of metal sorbents which capture mercury at ambient and high temperatures. The spent sorbents can be regenerated after exposure to mercury. The metal sorbents can be used as pure metals (or combinations of metals) or dispersed on an inert support to increase surface area per gram of metal sorbent. Iridium and ruthenium are effective for mercury removal from flue and smelter gases. Palladium and platinum are effective for mercury removal from fuel gas (syngas). An iridium-platinum alloy is suitable for metal capture in many industrial effluent gas streams including highly corrosive gas streams.

Granite, E.J.; Pennline, H.W.

2006-04-25

355

Determination of gas-liquid partition coefficients by automatic equilibrium headspace-gas chromatography utilizing the phase ratio variation method  

Microsoft Academic Search

The new phase ratio variation method is described which represents a convenient way for the determination of gas-liquid partition coefficients for practical purposes, utilizing equilibrium headspace-gas chromatography (EHS-GC). This method is based on the relationship between reciprocal peak area and the phase ratio in the vial containing the sample solution; it involves regression analysis of the EHS-GC measurements of a

L. S. Ettre; C. Welter; B. Kolb

1993-01-01

356

Methods of Off-Gas Flammability Control for DWPF Melter Off-Gas System at Savannah River Site  

Microsoft Academic Search

Several key operating variables affecting off-gas flammability in a slurry-fed radioactive waste glass melter are discussed, and the methods used to prevent potential off-gas flammability are presented. Two models have played a central role in developing such methods. The first model attempts to describe the chemical events occurring during the calcining and melting steps using a multistage thermodynamic equilibrium approach,

A. S. Choi; D. C. Iverson

1996-01-01

357

Optimizing the efficiency of evaporative cooling in optical dipole traps  

NASA Astrophysics Data System (ADS)

We present a combined computational and experimental study to optimize the efficiency of evaporative cooling for atoms in optical dipole traps. By employing a kinetic model of evaporation, we provide a strategy for determining the optimal relation between atom temperature, trap depth, and average trap frequency during evaporation given experimental initial conditions. We then experimentally implement a highly efficient evaporation process in an optical dipole trap, showing excellent agreement between the theory and experiment. This method has allowed the creation of pure Bose-Einstein condensates of 87Rb with 2×104 atoms starting from only 5×105 atoms initially loaded in the optical dipole trap, achieving an evaporation efficiency ?eff of 4.0 during evaporation.

Olson, Abraham J.; Niffenegger, Robert J.; Chen, Yong P.

2013-05-01

358

Evaporation control research, 1955-58  

USGS Publications Warehouse

One hundred fifty-two compounds and compositions of matter were screened as potential evaporation retardants. The homologous straight-chain fatty alkanols are considered the best materials for retardants. Several methods of application of the alkanols to the reservoir surface were investigated. Although wick-type drippers for the application of liquids and cage rafts for the application of solids appear to be the most promising methods from an economic standpoint, both methods have serious disadvantages. Considerable study was given to reducing biochemical oxidation of the evaporation retardants. Copper in several forms was found adequate as a bacteriostatic agent but posed a potential hazard because of its toxicity. Many other bactericides that were tested were also toxic. Two sets of large-scale field tests have been completed and several others are still in progress. On the larger reservoirs, the reduction of evaporation was not more than 20 percent under the prevailing conditions and the application procedure used. Three major practical problems remain; namely, the effects and action of wind on the monofilm, the effects of biochemical oxidation, and the most effective method of application. Fundamental problems remaining include the effects of various impurities, and the composition of the best evaporation retardant; the long-range effects of monofilms on the limnology of a reservoir, including the transfer of oxygen and carbon dioxide; toxicological aspects of all components of any evaporation-retardant composition, plus toxicology of any composition chosen for large-scale use; and further studies of the calorimetry and thermodynamics involved in the mechanism of evaporation and its reduction by a monofilm.

Cruse, Robert R.; Harbeck, Guy Earl.

1960-01-01

359

Semiconductor gas sensors based on nanostructured tungsten oxide  

Microsoft Academic Search

Semiconductor gas sensors based on nanocrystallline WO3 films were produced by two different methods. Advanced reactive gas evaporation was used in both cases either for a direct deposition of films (deposited films) or to produce ultra fine WO3 powder which was used for screen printing of thick films. The deposited films sintered at 480 °C and the screen-printed films sintered

J. L Solis; S Saukko; L Kish; C. G Granqvist; V Lantto

2001-01-01

360

Evaluation of Methods for Predictions Natural Gas Liquid Density  

Microsoft Academic Search

Due to the importance of liquid density in process design, this study was undertaken to evaluate the accuracy of available correlations, equations of state, and process simulation programs. The study covers natural gas liquid (NGL), liquefied natural gas (LNG) and light hydrocarbons mixtures containing nitrogen. More than 25 binary and multicomponent systems were studies. The accuracy of several correlations, EoSs,

Hameeda Dashti; Ali Moshfeghian; Mahmood Moshfeghian

361

Gas pipeline leak detection system using the online simulation method  

Microsoft Academic Search

Management of natural gas pipeline is an important task for economical and safety operation, loss prevention and environmental protection from methane emission. A leak detection of gas pipeline, therefore, plays a key role in the overall integrity management for a pipeline system. Especially for a long pipeline operated alongside of densely populated areas, a leak detection system is an indispensable

Reiko Maeshima; Akira Kinoshita; Hitoshi Shiraishi; Ichiro Koshijima

2000-01-01

362

Multicomponent gas mixture air bearing modeling via lattice Boltzmann method  

NASA Astrophysics Data System (ADS)

As the demand for ultrahigh recording density increases, development of an integrated head disk interface (HDI) modeling tool, which considers the air bearing and lubricant film morphology simultaneously is of paramount importance. To overcome the shortcomings of the existing models based on the modified Reynolds equation (MRE), the lattice Boltzmann method (LBM) is a natural choice in modeling high Knudsen number (Kn) flows owing to its advantages over conventional methods. The transient and parallel nature makes this LBM an attractive tool for the next generation air bearing design. Although LBM has been successfully applied to single component systems, a multicomponent system analysis has been thwarted because of the complexity in coupling the terms for each component. Previous studies have shown good results in modeling immiscible component mixtures by use of an interparticle potential. In this paper, we extend our LBM model to predict the flow rate of high Kn pressure-driven flows in multicomponent gas mixture air bearings, such as the air-helium system. For accurate modeling of slip conditions near the wall, we adopt our LBM scheme with spatially dependent relaxation times for air bearings in HDIs. To verify the accuracy of our code, we tested our scheme via simple two-dimensional benchmark flows. In the pressure-driven flow of an air-helium mixture, we found that the simple linear combination of pure helium and pure air flow rates, based on helium and air mole fraction, gives considerable error when compared to our LBM calculation. Hybridization with the existing MRE database can be adopted with the procedure reported here to develop the state-of-the-art slider design software.

Tae Kim, Woo; Kim, Dehee; Hari Vemuri, Sesha; Kang, Soo-Choon; Seung Chung, Pil; Jhon, Myung S.

2011-04-01

363

Method for controlling the capacity of a blower and a device for controlling the pressure in a liquefied gas storage tank utilizing said method  

Microsoft Academic Search

A method of controlling the capacity of a gas blower for pumping gas at a given discharge pressure involves the cooling of the gas at the suction side of the blower. The method is especially useful for controlling the pressure in a liquefied gas storage tank so as to maintain it substantially constant. The boil-off gas in the tank is

Seki

1977-01-01

364

New mathematical method for the solution of gas-gas equilibria with special application to HTGR primary-coolant environments  

SciTech Connect

A new mathematical method and corresponding computer program have been developed that provide a general method for the numerical solution of an equilibrium problem involving the chemical interactions of gaseous species. The method and computer code were developed to calculate the equilibrium concentrations of impurity gases, such as CO, CO/sub 2/, H/sub 2/, H/sub 2/O, CH/sub 4/, and O/sub 2/, which may be approached as the result of gaseous chemical reactions occurring within the hot primary coolant helium of a high-temperature gas-cooled reactor (HTGR). The method, however, can be applied to any gas mixture.

Bongartz, K.

1983-07-01

365

Determination of gas phase adsorption isotherms—a simple constant volume method  

Microsoft Academic Search

Single and ternary solute gas phase adsorption isotherms were conducted in this study to evaluate the effectiveness of a simple constant volume method, which was utilized by using Tedlar gas sampling bags as a constant volume batch reactor. For this purpose, gas phase adsorption of toluene, methyl ethyl ketone (MEK), and methyl isobutyl ketone (MIBK) on two types of activated

Daekeun Kim; Zhangli Cai; George A. Sorial

2006-01-01

366

A Gas Chromatographic Analysis of Fecal Short-Chain Fatty Acids, Using the Direct Injection Method  

Microsoft Academic Search

A simple, reproducible, and rapid gas chromatographic method for short-chain fatty acid determination in human feces was developed. It involves direct injection of fecal supernatants into the gas chromatograph, without any pretreatment. Contamination of the gas chromatographic column with nonvolatile fecal material was prevented by the use of a glass liner in the injector. This liner, which acted as a

Albert Tangerman; Fokko M. Nagengast

1996-01-01

367

Method for the removal of elemental mercury from a gas stream  

DOEpatents

A method is provided to remove elemental mercury from a gas stream by reacting the gas stream with an oxidizing solution to convert the elemental mercury to soluble mercury compounds. Other constituents are also oxidized. The gas stream is then passed through a wet scrubber to remove the mercuric compounds and oxidized constituents.

Mendelsohn, Marshall H. (Downers Grove, IL); Huang, Hann-Sheng (Darien, IL)

1999-01-01

368

Method for the removal of elemental mercury from a gas stream  

DOEpatents

A method is provided to remove elemental mercury from a gas stream by reacting the gas stream with an oxidizing solution to convert the elemental mercury to soluble mercury compounds. Other constituents are also oxidized. The gas stream is then passed through a wet scrubber to remove the mercuric compounds and oxidized constituents. 7 figs.

Mendelsohn, M.H.; Huang, H.S.

1999-05-04

369

Based on the probability estimation of gas coal-dust explosion risk evaluation method  

Microsoft Academic Search

Because the present safety evaluation could not exactly make the quantitative conclusions, this paper analyzes the reasons why the present evaluation methods are difficult to make the quantitative conclusions and provides the probability estimation method of the gas and coal dust explosion risk. Using this method determines the gas and coal dust explosion risk and gets the quantitative results of

Jianhua Sun; Shang Xie; Chunrong Wei; Jingpeng Zhang; Yi Zhao

2011-01-01

370

Method of cooling gas only nozzle fuel tip  

DOEpatents

A diffusion flame nozzle gas tip is provided to convert a dual fuel nozzle to a gas only nozzle. The nozle tip diverts compressor discharge air from the passage feeding the diffusion nozzle air swirl vanes to a region vacated by removal of the dual fuel components, so that the diverted compressor discharge air can flow to and through effusion holes in the end cap plate of the nozzle tip. In a preferred embodiment, the nozzle gas tip defines a cavity for receiving the compressor discharge air from a peripheral passage of the nozzle for flow through the effusion openings defined in the end cap plate.

Bechtel, William Theodore (Scotia, NY); Fitts, David Orus (Ballston Spa, NY); DeLeonardo, Guy Wayne (Glenville, NY)

2002-01-01

371

Efficiency of Using Solid Wood Fuels in Maple Syrup Evaporators.  

National Technical Information Service (NTIS)

A study of commercial, wood-fired evaporators revealed that normal expected thermal efficiencies are between 35 to 50 percent. The moisture content and quality of wood fuels used and the design and method of firing the evaporator are critical in determini...

L. D. Garrett

1981-01-01

372

Evaporation rate as a function of water salinity  

Microsoft Academic Search

Water evaporation is an important physical phenomenon that occurs in nature and in several industrial applications. Many researchers are working in this area to establish a good correlation that can be used to measure evaporation rates precisely. In this article, we review previous experience by describing the instrument used, method of measurement, conditions of experimentation and correlations resulting from these

M. Al-Shammiri

2002-01-01

373

Water storage and evaporation as constituents of rainfall interception  

Microsoft Academic Search

Intercepted rainfall may be evaporated during or after the rain event. Intercepted rain is generally determined as the difference between rainfall measurements outside and inside the forest. Such measurements are often used to discriminate between water storage and evaporation during rain as well. Two well-accepted methods underestimate water storage by a factor two as compared to direct observations. The underestimation

Wim Klaassen; Fred Bosveld; E. de Water

1998-01-01

374

METHOD AND APPARATUS FOR PRODUCING INTENSE ENERGETIC GAS DISCHARGES  

DOEpatents

A device for producing an energetic gas arc discharge employing the use of gas-fed hollow cathode and anode electrodes is reported. The rate of feed of the gas to the electrodes is regulated to cause complete space charge neutralization to occur within the electrodes. The arc discharge is closely fitted within at least one of the electrodes so tint the gas fed to this electrode is substantially completely ionized before it is emitted into the vacuum chamber. It is this electrode design and the axial potential gradient that exists in the arc which permits the arc to be operated in low pressures and at volthges and currents that permit the arc to be energetic. The use of the large number of energetic ions that are accelerated toward the cathode as a propulsion device for a space vehicle is set forth.

Bell, P.R.; Luce, J.S.

1960-01-01

375

Comparative Assessment of Advanced Gas Hydrate Production Methods.  

National Technical Information Service (NTIS)

Displacing natural gas and petroleum with carbon dioxide is a proven technology for producing conventional geologic hydrocarbon reservoirs, and producing additional yields from abandoned or partially produced petroleum reservoirs. Extending this concept t...

B. P. McGrail M. D. White S. K. Wurstner

2009-01-01

376

A calorimeter for measuring liquid evaporation rates  

Microsoft Academic Search

Describes a simple calorimetric procedure which allows the measurement of evaporation rates of liquids over a range of temperatures and hydrodynamic conditions. The method is rapid, its accuracy is about +or-3% and it may be used with small volumes of sample (100 mu l and less). Results obtained for a representative group of substances are presented.

C. A. Reading; A. Reiser

1977-01-01

377

Improved method for removing metal vapor from gas streams  

DOEpatents

This invention relates to a process for gas cleanup to remove one or more metallic contaminants present as vapor. More particularly, the invention relates to a gas cleanup process using mass transfer to control the saturation levels such that essentially no particulates are formed, and the vapor condenses on the gas passage surfaces. It addresses the need to cleanup an inert gas contaminated with cadmium which may escape from the electrochemical processing of Integral Fast Reactor (IFR) fuel in a hot cell. The IFR is a complete, self-contained, sodium-cooled, pool-type fast reactor fueled with a metallic alloy of uranium, plutonium and zirconium, and is equipped with a close-coupled fuel cycle. Tests with a model have shown that removal of cadmium from argon gas is in the order of 99.99%. The invention could also apply to the industrial cleanup of air or other gases contaminated with zinc, lead, or mercury. In addition, the invention has application in the cleanup of other gas systems contaminated with metal vapors which may be toxic or unhealthy.

Ahluwalia, R.K.; Im, K.H.

1994-09-19

378

Methods of Off-Gas Flammability Control for DWPF Melter Off-Gas System at Savannah River Site  

SciTech Connect

Several key operating variables affecting off-gas flammability in a slurry-fed radioactive waste glass melter are discussed, and the methods used to prevent potential off-gas flammability are presented. Two models have played a central role in developing such methods. The first model attempts to describe the chemical events occurring during the calcining and melting steps using a multistage thermodynamic equilibrium approach, and it calculates the compositions of glass and calcine gases. Volatile feed components and calcine gases are fed to the second model which then predicts the process dynamics of the entire melter off-gas system including off-gas flammability under both steady state and various transient operating conditions. Results of recent simulation runs are also compared with available data

Choi, A.S. [Westinghouse Savannah River Company, AIKEN, SC (United States); Iverson, D.C.

1996-05-02

379

Experimental Investigations of the Internal Energy of Molecules Evaporated via Laser-induced Acoustic Desorption into a Fourier-transform Ion Cyclotron Resonance Mass Spectrometer (LIAD/FT-ICR)  

PubMed Central

The internal energy of neutral gas-phase organic and biomolecules, evaporated by means of laser-induced acoustic desorption (LIAD) into a Fourier-transform ion cyclotron resonance mass spectrometer (FT-ICR), was investigated through several experimental approaches. The desorbed molecules were demonstrated not to undergo degradation during the desorption process by collecting LIAD-evaporated molecules and subjecting them to analysis by electrospray ionization/quadrupole ion trap mass spectrometry. Previously established gas-phase basicity (GB) values were remeasured for LIAD-evaporated organic molecules and biomolecules with the use of the bracketing method. No endothermic reactions were observed. The remeasured basicity values are in close agreement with the values reported in the literature. The amount of internal energy deposited during LIAD is concluded to be less than a few kcal/mol. Chemical ionization with a series of proton transfer reagents was employed to obtain a breakdown curve for a protonated dipeptide, val-pro, evaporated by LIAD. Comparison of this breakdown curve with a previously published analogous curve obtained by using substrate-assisted laser desorption (SALD) to evaporate the peptide suggests that the molecules evaporated via LIAD have less internal energy than those evaporated via SALD.

Shea, Ryan C.; Petzold, Christopher J.; Liu, Ji-ang; Kenttamaa, Hilkka I.

2008-01-01

380

Estimating daily pan evaporation using adaptive neural-based fuzzy inference system  

Microsoft Academic Search

Estimation of evaporation is important for water planning, management, and hydrological practices. There are many available\\u000a methods to estimate evaporation from a water surface, comprising both direct and indirect methods. All the evaporation models\\u000a are based on crisp conceptions with no uncertainty element coupled into the model structure although in daily evaporation\\u000a variations there are uncontrollable effects to a certain

M. Erol Keskin; Özlem Terzi; Dilek Taylan

2009-01-01

381

High-temperature gas stream filter and method  

DOEpatents

The present invention relates generally to the removal of solid particulate material from high-temperature gas streams, and more particularly the removal of such particulate material by employing a barrier filter formed of a carbon-carbon composite provided by a porous carbon fiber substrate with open interstitial regions between adjacently disposed carbon fibers selectively restricted by carbon integrally attached to the carbon fibers of the substrate. In a typical utilization of a particulate-bearing hot gas stream, the particulate loading of the gas stream after cleaning is normally less than about 50 ppm and with essentially no particulates larger than about 10 microns. This carbon-carbon filter for removing particulate material of a particle size larger than a preselected particle size from a gas stream at a temperature greater than about 800 F, is produced by the steps which comprise: providing a substrate of carbonaceous fibers with pore-forming open interstitial regions between adjacently disposed fibers; and, sufficiently filling these open interstitial regions with carbon integrally attached to and supported by the fibers for providing the interstitial regions with throughgoing passage-ways of a pore size sufficient to provide for the passage of the gas stream while preventing the passage of particulate material larger than a preselected particle size.

Notestein, J.E.

1994-12-31

382

Preparation of Calibration Gas Mixtures Using a Dynamic Volumetric Method for Environmental Monitoring  

Microsoft Academic Search

It is difficult to produce and maintain the quality of calibration gas mixtures stable and reliable in gas cylinders for the identification and quantification of trace environmental contaminants. Dynamic method has attracted an attention because immediate and on-site generation of calibration gas mixture is achievable in the range of percent, sub-ppm, and micro-mole fraction. The dynamic method for the preparation

S. Lee; W. Lee; S. Oh

2008-01-01

383

Turkish Undergraduates' Misconceptions of Evaporation, Evaporation Rate, and Vapour Pressure  

Microsoft Academic Search

This study focused on students' misconceptions related to evaporation, evaporation rate, and vapour pressure. Open-ended diagnostic questions were used with 107 undergraduates in the Primary Science Teacher Training Department in a state university in Turkey. In addition, 14 students from that sample were interviewed to clarify their written responses and to further probe their understandings of the questions asked in

Nurtaç Canpolat

2006-01-01

384

Turkish Undergraduates' Misconceptions of Evaporation, Evaporation Rate, and Vapour Pressure  

ERIC Educational Resources Information Center

This study focused on students' misconceptions related to evaporation, evaporation rate, and vapour pressure. Open-ended diagnostic questions were used with 107 undergraduates in the Primary Science Teacher Training Department in a state university in Turkey. In addition, 14 students from that sample were interviewed to clarify their written…

Canpolat, Nurtac

2006-01-01

385

Researching into Microbial-Limestone new wet flue gas desulfurization method  

Microsoft Academic Search

It is summarized the research hotspots of flue gas desulfurization (FGD) and analyzed the advantages and disadvantages of Limestone-Gypsum wet flue gas desulfurization (WFGD) and microbic desulfurization methods. Put forward a new idea of combining the Limestone-Gypsum WFGD, microbial method with catalytic oxidation of transition metal (Fe 3+ \\/Fe 2+

Junjiang Bao; Rui Tian; Xiaoxia Zhao; Chenxia Jia

2011-01-01

386

PROCEDURE FOR MEASURING FREON 114 LEAK RATES IN CASCADE COOLANT CONDENSERS BY THE GAS DILUTION METHOD  

Microsoft Academic Search

The gas dilution method for the measurement of Freon leak rates to the ; water side of cascade coolant condensers has been tested on various condensers in ; the X-333 building and on one condenser in the X-330 building. The gas dilution ; method involves injecting Freon 115 (CClFâ--CFâ) into the water inlet ; of a condenser suspected of leaking

1958-01-01

387

Method for combined removal of mercury and nitrogen oxides from off-gas streams  

DOEpatents

A method for removing elemental Hg and nitric oxide simultaneously from a gas stream is provided whereby the gas stream is reacted with gaseous chlorinated compound to convert the elemental mercury to soluble mercury compounds and the nitric oxide to nitrogen dioxide. The method works to remove either mercury or nitrogen oxide in the absence or presence of each other.

Mendelsohn, Marshall H. (Downers Grove, IL); Livengood, C. David (Lockport, IL)

2006-10-10

388

Two methods for calculating regional cerebral blood flow from emission computed tomography of inert gas concentrations  

Microsoft Academic Search

Two methods are described for calculation of regional cerebral blood flow from completed tomographic data of radioactive inert gas distribution in a slice of brain tissue. It is assumed that the tomographic picture gives the average inert gas concentration in each pixel over data collection periods of 30 to 60 sec. In the early picture method a single picture taken

I. Kanno; N. A. Lassen

1979-01-01

389

Gas chromatographic method for measuring nitrogen dioxide and peroxyacetyl nitrate in air without compressed gas cylinders  

SciTech Connect

A gas chromatographic technique that measures atmospheric concentrations of peroxyacetyl nitrate (PAN) and NO/sub 2/ has been developed that uses luminol-based chemiluminescence for detection. The carrier gas is air that has been scrubbed by passing it over FeSO/sub 4/, which eliminates the need for any compressed gas cylinders. A novel gas sampling system and time enable variable sample volumes of contaminated air to be injected. Ambient PAN and NO/sub 2/ measurements can be made every 40 s with detection limits of 0.12 ppb for PAN and 0.2 ppb for NO/sub 2/. Seven other atmospheric species, including ozone, gave no interference. Linear response was observed for NO/sub 2/ from 0.2 to 170 ppb and for PAN from 1 to 70 ppb.

Burkhardt, M.R.; Maniga, N.I.; Stedman, D.H.; Paur, R.J.

1988-04-15

390

Method and apparatus for measuring the gas permeability of a solid sample  

DOEpatents

The disclosure is directed to an apparatus and method for measuring the permeability of a gas in a sample. The gas is allowed to reach a steady flow rate through the sample. A measurable amount of the gas is collected during a given time period and then delivered to a sensitive quadrupole. The quadrupole signal, adjusted for background, is proportional to the amount of gas collected during the time period. The quadrupole can be calibrated with a standard helium leak. The gas can be deuterium and the sample can be polyvinyl alcohol.

Carstens, D.H.W.

1984-01-27

391

A Comparison of Infrared and Gas Chromatographic Methods for Determination of Methane in Mine Air.  

National Technical Information Service (NTIS)

The gas chromatographic method, devised by the Bureau of Mines for analyzing routine mine air samples, was compared with the infrared method used for confirmatory determination of methane in mine air. While maintaining the specificity of the infrared meth...

R. W. Freedman H. W. Lang

1968-01-01

392

Vibrating capacitor method in the development of semiconductor gas sensors  

Microsoft Academic Search

Adsorption usually results in work function shifts on catalytically active surfaces such as semiconductor gas sensors. The purpose of the present article is to summarise the capabilities of the vibrating capacitor from the simplest adsorption-induced work function tests to the scanning, vibrating, capacitor-yielded olfactory pictures and other chemical pictures. After a brief history and review of theoretical bases, the latest

János Mizsei

2005-01-01

393

Evaluation of the freeze-thaw\\/evaporation process for the treatment of produced waters. Final report, August 1992August 1996  

Microsoft Academic Search

The use of freeze-crystallization is becoming increasingly acknowledged as a low-cost, energy-efficient method for purifying contaminated water. The natural freezing process can be coupled with natural evaporative processes to treat oil and gas produced waters year round in regions where subfreezing temperatures seasonally occur. The climates typical of Colorado`s San Juan Basin and eastern slope, as well as the oil

J. E. Boysen; K. L. Walker; J. L. Mefford; J. R. Kirsch; J. A. Harju

1996-01-01

394

Evaporation-driven assembly as a route to photonic materials  

NASA Astrophysics Data System (ADS)

The unique, structure-dependent diffraction properties of photonic crystals have inspired their proposed use in applications ranging from chemosensors, to solar power applications, to optical computing devices. The range of proposed applications for photonic crystals demands a range of techniques for fabricating them, meeting differently weighted priorities including perfection, refractive index contrast, operating wavelength, throughput, and economy. This thesis contributes to the art of preparing photonic crystals by colloidal self-assembly at an evaporating solvent-air interface, a promising approach for preparing thin films of photonic material over large areas at low cost, if some defects are permissible. The simplest possible example of evaporation-driven self-assembly, the evaporation of a stagnant colloidal suspension, is demonstrated as a practical method for colloidal crystallization; although the colloidal crystal is formed at a water-air interface, and so is difficult to handle, it can be made robust for study and use by immobilization in a hydrogel. Vertical deposition is a widely used evaporation-based method for preparing thin, dry colloidal crystal films. The thickness profiles of vertically deposited colloidal crystals are measured through the Fabry-Perot fringes in their infrared reflectance spectra: the linear shape of these thickness profiles constrains proposed mechanisms for colloidal self-assembly in vertical deposition. Optimized conditions for vertical deposition are found under which colloidal crystals of 80% peak reflectance, an exceptional optical performance for a polystyrene colloid crystal on glass, are reproducibly prepared. A process is demonstrated for preparing germanium-containing, high-index-contrast photonic crystals from a polystyrene colloidal crystal template and pre-formed germanium nanoparticles, using only room-temperature processing steps; the result is an inverse opal of air macropores in a germanium-in-photoadhesive composite with refractive index 2.05. Previously published germanium infiltration techniques rely on gas-phase chemical reactions and require temperatures well above Tg for most linear polymers. As a complementary approach to this problem, some progress has also been made towards a polymer colloidal crystal template that can withstand gasphase chemistry at temperatures up to and possibly beyond 250°C, based on highly crosslinked divinylbenzene microspheres.

Shimmin, Robert G.

395

Reservoir Evaporation Prediction Using Data Driven Techniques  

Microsoft Academic Search

Evaporation in reservoirs plays a prominent role in water resources planning, operation, and management because a considerable amount of water is lost through evaporation, especially in large reservoirs. Estimating evaporation from surface water usually requires ample data that are not easily measurable. At present, in India, reservoir evaporation is estimated from the pan evaporation and average water spread area. Because

R. Arunkumar; V. Jothiprakash

2013-01-01

396

Spin coating with slow evaporation  

Microsoft Academic Search

The spin coating of polymer solutions is discussed, with emphasis on the nature of the evaporation boundary condition. A dimensional analysis reveals that the appropriate condition is a constant small evaporation rate, which is determined by the mass transfer in the adjacent atmosphere. An error in previous work [Phys. Fluids 31, 2786 (1988)] is brought to light, and it is

C. J. Lawrence

1990-01-01

397

Evaporative cooling of sodium atoms  

Microsoft Academic Search

We have observed evaporative cooling of magnetically trapped sodium atoms. A novel technique, rf induced evaporation, was used to reduce the temperature by a factor of 12 and increase the phase space density by more than 2 orders of magnitude. The elastic collision cross section of cold sodium atoms in the {ital F}=1, {ital m}{sub {ital F}}=-1 hyperfine state was

Kendall B. Davis; Marc-Oliver Mewes; Michael A. Joffe; Michael R. Andrews; Wolfgang Ketterle

1995-01-01

398

Evaporators with inverted circulation loops  

Microsoft Academic Search

The evaporator operated under atmospheric pressure and under 620 mm Hg vacuum processing saturated solutions of sodium chloride (direct solubility: solubility increases at highertemperatur e) and sodium sulfate (inverse solubility: solubility decreases at higher temperature). These solutions were evaporated with crystal circulation and also with separation of crystals (clarification) by inserting a removable baffle into the separator to remove large

E. M. Kovalev; Z. F. Kostenko

1971-01-01

399

EVAPORATION OF FRUITS AND VEGETABLES  

PubMed Central

More and more the world is utilizing dried fruits and vegetables, the war having given impetus to the preparation of the latter. Here are plain statements of processes and values deduced from scientific institution investigations. Evaporation is in its infancy while sun drying is very ancient. Evaporated products are better looking but more costly. ImagesFigure 1Figure 2Figure 3

Cruess, W. V.

1921-01-01

400

Usability of calcium carbide gas pressure method in hydrological sciences  

NASA Astrophysics Data System (ADS)

CCGP can be used as a rapid ground truthing method for soil moisture measurements.Expected accuracy of the CCGP method is mostly within ±1%.CCGP can be used as stand alone method for small scale hydrological applications.

Arsoy, S.; Ozgur, M.; Keskin, E.; Yilmaz, C.

2013-10-01

401

Comparative Evaluation of Two Methods to Estimate Natural Gas Production in Texas  

EIA Publications

This report describes an evaluation conducted by the Energy Information Administration (EIA) in August 2003 of two methods that estimate natural gas production in Texas. The first method (parametric method) was used by EIA from February through August 2003 and the second method (multinomial method) replaced it starting in September 2003, based on the results of this evaluation.

Information Center

2003-12-23

402

Experimental Investigation of Microstructured Evaporators  

NASA Astrophysics Data System (ADS)

Microfluidic devices have become more and more popular over the last decades [1]. Cooling is a topic where microstructures offer significant advantages compared to conventional techniques due the much higher possible surface to volume ratios and short heat transfer lengths. By evaporating of a fluid in microchannels, compact, fast and powerful cooling devices become possible [2]. Experimental results for different designs of microstructured evaporators are presented here. They have been obtained either using water as evaporating coolant or the refrigerant R134a (Tetrafluoroethane). A new microstructured evaporator design consisting of bended microchannels instead of straight channels for a better performance is shown and compared to previous results [2] for the evaporation of R134a in straight microchannels.

Wibel, W.; Westermann, S.; Maikowske, S.; Brandner, J. J.

2012-11-01

403

Flash evaporation of liquid monomer particle mixture  

DOEpatents

The present invention is a method of making a first solid composite polymer layer. The method has the steps of (a) mixing a liquid monomer with particles substantially insoluble in the liquid monomer forming a monomer particle mixture; (b) flash evaporating the particle mixture and forming a composite vapor; and (c) continuously cryocondensing said composite vapor on a cool substrate and cross-linking the cryocondensed film thereby forming the polymer layer.

Affinito, John D. (Kennewick, WA); Darab, John G. (Richland, WA); Gross, Mark E. (Pasco, WA)

1999-01-01

404

Flash evaporation of liquid monomer particle mixture  

DOEpatents

The present invention is a method of making a first solid composite polymer layer. The method has the steps of (a) mixing a liquid monomer with particles substantially insoluble in the liquid monomer forming a monomer particle mixture; (b) flash evaporating the particle mixture and forming a composite vapor; and (c) continuously cryocondensing said composite vapor on a cool substrate and cross-linking the cryocondensed film thereby forming the polymer layer. 3 figs.

Affinito, J.D.; Darab, J.G.; Gross, M.E.

1999-05-11

405

Long term measurement of lake evaporation using a pontoon mounted Eddy Covariance system  

NASA Astrophysics Data System (ADS)

Accurate quantification of evaporation from water storages is essential for design of water management and allocation policy that aims to balance demands for water without compromising the sustainability of future water resources, particularly during periods of prolonged and severe drought. Precise measurement of evaporation from lakes and dams however, presents significant research challenges. These include design and installation of measurement platforms that can withstand a range of wind and wave conditions; accurate determination of the evaporation measurement footprint and the influence of changing water levels. In this paper we present results from a two year long deployment of a pontoon mounted Eddy Covariance (EC) system on a 17.2ha irrigation reservoir in southeast Queensland, Australia. The EC unit included a CSAT-3 sonic anemometer (Campbell Scientific, Utah, United States) and a Li-Cor CS7500 open-path H2O/CO2 infrared gas analyzer (LiCor, Nebraska, United States) at a height of 2.2m, a net radiometer (CNR1, Kipp & Zonen, Netherlands) at a height of 1.2m and a humidity and temperature probe (HMP45C,Vaisala, Finland) at 2.3m. The EC unit was controlled by a Campbell Scientific CR3000 data logger with flux measurements made at 10 Hz and block averaged values logged every 15 minutes. Power to the EC system was from mounted solar panels that charged deep cycle lead-acid batteries while communication was via a cellphone data link. The pontoon was fitted with a weighted central beam and gimbal ring system that allowed self-levelling of the instrumentation and minimized dynamic influences on measurements (McGowan et al 2010; Wiebe et al 2011). EC measurements were corrected for tilt errors using the double rotation method for coordinate rotation described by Wilczak et al. (2001). High and low frequency attenuation of the measured co-spectrum was corrected using Massman's (2000) method for estimating frequency response corrections, while measurements were corrected for density fluctuations using the method of Webb-Pearman-Leuning (Webb et al. 1980). The evaporation measurement footprint over the reservoir was determined using the SCADIS one and a half order turbulence closure footprint model (Sogachev and Lloyd, 2004). Comparison of EC measured evaporation rates show excellent agreement with independent measurement of evaporation by scintillometer under a wide range of conditions (McJannet et al 2011). They confirm that pontoon mounted EC systems offer a robust, highly portable and reliable cost effective approach for accurate quantification of evaporation from reservoirs.

McGowan, H. A.; McGloin, R.; McJannet, D.; Burn, S.

2011-12-01

406

Field Evaluation of Gas Well Stimulation Methods Sutton County, Texas  

Microsoft Academic Search

Attempts to stimulate marginal gas producers in Sutton County, Texas, has provided an opportunity to evaluate several types of stimulation fluids on a comparative basis. The fluids used included water-base, oil-base, and acid-base fluids. A thorough study of the production history of wells following treatment demonstrates the effectiveness of the different fluids on a long term basis. Conclusions drawn from

C. F. Smith; D. L. Murphy

1974-01-01

407

Influence of Refractance Window evaporation on quality of juices from small fruits  

Microsoft Academic Search

A new type of evaporator (Refractance Window® (RW) evaporator) has been developed that operates at atmospheric conditions and uses thermal energy from hot water to concentrate foods. The influence of product temperature and dissolved solids on vitamin C in blueberry juice and color of cranberry juice was evaluated in this new evaporation method in comparison with conventional falling film multi-effect

C. I. Nindo; J. R. Powers; J. Tang

2007-01-01

408

Investigation of the process of liquid evaporation from a porous metal under vacuum conditions  

Microsoft Academic Search

The method and results of an investigation of the evaporation of water into a vacuum are described. The steady-state regime of evaporation in a porous metal is examined. The dependence of the evaporation rate on the parameters of the porous metal and the heat flux density has been experimentally determined. The temperature distribution in the porous plate is determined theoretically.

V. I. Balakhonova; P. A. Novikov; B. M. Smol'skii; V. V. Selivanov; V. N. Shmigora

1968-01-01

409

Developing Pan Evaporation to Grass Reference Evapotranspiration Conversion Model a Case Study in Khuzestan Province  

Microsoft Academic Search

In the present study, pan evaporation data and the data required for estimating reference evapotranspiration were collected from 10 meteorological stations in Khuzestan Province using the Penman-Monteith method. Three first, second and third order polynomial models were studied for conversion of pan evaporation data to grass reference evapotranspiration with pan evaporation, wind speed and air humidity as the main variables.

Ali Rahimi Khoob; Seyedmahmoudreza Behbahani; Mohammad Hadi Nazarifar

2007-01-01

410

Numerical evaluation of subsurface soil water evaporation derived from sensible heat balance  

Microsoft Academic Search

A recently introduced measurement approach allows in situ determination of subsurface soil water evaporation by means of heat-pulse probes (HPP). The latent heat component of subsurface evaporation is estimated from the residual of the sensible heat balance. This heat balance method requires measurement of vertical soil temperature and estimates of thermal properties for soil water evaporation determination. Our objective was

Masaru Sakai; Scott B. Jones; Markus Tuller

2011-01-01

411

Flash evaporation of TiNi shape memory thin film for microactuators  

Microsoft Academic Search

The flash evaporation, with which material for deposition is repeatedly evaporated in very small volumes, was investigated for formation of TiNi shape memory alloy thin film. Along with the flash method itself, the timing for opening the shutter proved a crucial factor in controlling thin film composition. Using our evaporation system, a thin film with a composition of around 50

Eiji Makino; M. Uenoyama; T. Shibata

1998-01-01

412

Design methodology for a salt gradient solar pond coupled with an evaporation pond  

Microsoft Academic Search

This paper presents the results of a simple mathematical model for predicting the ratio of the evaporation pond (EP) area to that of a Salt Gradient Solar Pond (SGSP) area. The EP idea provides a very attractive method of salt recycling by evaporation, especially in areas of high rates of evaporation and low rates of rain as it is the

K. R. Agha; S. M. Abughres; A. M. Ramadan

2002-01-01

413

Efficiency of using solid wood fuels in maple syrup evaporators. Forest service research paper (final)  

SciTech Connect

A study of commercial, wood-fired evaporators revealed that normal expected thermal efficiencies are between 35 to 50 percent. The moisture content and quality of wood fuels used and the design and method of firing the evaporator are critical in determining evaporator efficiency and the economic implications of using wood.

Garrett, L.D.

1981-01-01

414

Direct observation of blocked nanoscale surface evaporation on SiO2 nanodroplets  

NASA Astrophysics Data System (ADS)

Nano-scale surface evaporation of SiO2 nanodroplets from a volcano-shaped tip (tip diameter d ~ 20 nm to 70 nm) was observed directly using an in situ transmission electron microscopy method. Au nanoparticles, those precipitated in the SiO2 matrix after an Au catalyzed growth, diffused and pinned onto the evaporation surface, which induced blocked evaporation dynamics. Our observations provide direct evidences of blocked evaporation dynamics caused by small-sized nanoparticles at the nanometer scale.

Wan, Neng; Xu, Jun; Sun, Li-Tao; Martini, Matteo; Huang, Qing-An; Hu, Xiao-Hui; Xu, Tao; Bi, Heng-Chang; Sun, Jun

2012-10-01

415

CHEMISTRY IN EVAPORATING ICES-UNEXPLORED TERRITORY  

SciTech Connect

We suggest that three-body chemistry may occur in warm high-density gas evaporating in transient co-desorption events on interstellar ices. Using a highly idealized computational model we explore the chemical conversion from simple species of the ice to more complex species containing several heavy atoms, as a function of density and of adopted three-body rate coefficients. We predict that there is a wide range of densities and rate coefficients in which a significant chemical conversion may occur. We discuss the implications of this idea for the astrochemistry of hot cores.

Cecchi-Pestellini, Cesare [INAF-Osservatorio Astronomico di Cagliari, Strada n.54, Loc. Poggio dei Pini, 09012 Capoterra (Italy); Rawlings, Jonathan M. C.; Viti, Serena; Williams, David A., E-mail: ccp@ca.astro.i, E-mail: jcr@star.ucl.ac.u, E-mail: sv@star.ucl.ac.u, E-mail: daw@star.ucl.ac.u [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom)

2010-12-20

416

Method for the recovery of clean pyrolysis off-gas and a rotary recycling means therefor  

Microsoft Academic Search

A method and apparatus for stripping entrained organic vapor and solid particulate matter from a pyrolytic off-gas stream is disclosed. The off-gas is introduced at the top of a conical chamber having a variable speed ''squirrel cage'' rotor at its top. The wet, dirty, off-gas is drawn into the rotor from below and impinged upon the chamber walls which causes

L. W. Elston; D. R. Hurst

1981-01-01

417

Solid sorbent method for the collection and analysis of volatile halogenated organic compounds in soil gas  

Microsoft Academic Search

A solid sorbent technique was developed to measure volatile halogenated organic compounds (VHOCs) in soil gas. The VHOCs were preconcentrated onto graphitized carbon black (Carbotrap) and analyzed by thermal desorption\\/high-resolution gas chromatography with electron-capture detection. The method detection limit (MDL) for trichloromethane (CHCl3) and tetrachloromethane (CCl4) in soil gas was approximately 1 ?g m?3 for a 60-ml sample volume. A

Paul V. Doskey; Molly S. Costanza; Mary C. Hansen; Wayne T. Kickels

1996-01-01

418

Oil shale process water evaporation. Final report.  

National Technical Information Service (NTIS)

The primary objectives of this research program were to study chemical, microclimatological, and interactive effects on the evaporation of low-quality oil shale process wastewaters to develop more applicable evaporation models and evaporation design crite...

V. R. Hasfurther T. Reeves

1990-01-01

419

Frost retardation of an air-source heat pump by the hot gas bypass method  

Microsoft Academic Search

This study is concerned with a hot gas (refrigerant) bypass method to retard the formation and propagation of frost in an air-source heat pump. The feasibility of the hot gas bypass method was investigated experimentally and the method's performance is compared with that of a normal, 1.12kW capacity air-source heat pump system with no defrost equipment such as an electric

Ju-Suk Byun; Jinho Lee; Chang-Duk Jeon

2008-01-01

420

Novel technology for hydrothermal treatment of NPP evaporator concentrates  

SciTech Connect

A novel technology was developed for treatment of evaporator concentrates produced as a result of operation of evaporation devices comprising the main component of special water purification systems of nuclear power plants (NPP). The developed technology includes a hydrothermal (T=250-300 deg. C and P=80-120 bar) processing of evaporator concentrates in oxidation medium in order to destruct stable organic complexes of cobalt radionuclides and remove these radionuclides by oxide materials formed during such a processing. The cesium radionuclides contained in evaporator concentrates are removed by a conventional method-through application of one of the developed composite sorbents with ferrocyanides of transition metals used as active agents. Extensive laboratory studies of the processes occurring in evaporator concentrates under hydrothermal conditions were performed. It was shown that hydrothermal oxidation of evaporator concentrates has a number of advantages as compared to traditional oxidation methods (ozonization, photo-catalytic, electrochemical and plasma oxidation). A laboratory installation was built for the flow-type hydrothermal oxidation of NPP evaporator concentrates. The obtained experimental results showed good prospects for the developed method application. On the basis of the results obtained, a pilot installation of productivity up to 15 l/hour was developed and built in order to work out the technology of evaporator concentrates hydrothermal treatment. The pilot tests of the hydrothermal technology for evaporator concentrates hydrothermal treatment were performed for 6 months in 2006 at the 1. reactor unit of the Novovoronezhskaya NPP (Voronezh Region, Russia). Optimal technological regimes were determined, and estimations of the economic soundness of the technology were made. The advantages of the presented technology in terms of management of concentrated liquid radioactive wastes (LRW) at nuclear cycle facilities, as compared to other methods applicable for this type of LRW, were demonstrated. Application of the hydrothermal technology in the system of NPP LRW management enables one to reduce substantially the volume of solid radioactive waste sent for final disposal. (authors)

Avramenko, Valentin; Dobrzhansky, Vitaly; Marinin, Dmitry; Sergienko, Valentin; Shmatko, Sergey [Institute of Chemistry, Far East Department, Russian Academy of Sciences (Russian Federation)

2007-07-01

421

Good odorant practices ensure safer operations. [Natural gas odorant detection methods  

SciTech Connect

Regulations in Canada and the US require that combustible gas used as a fuel be odorized at such a level that a concentration in air of one-fifth the lower explosive limit the gas can be readily detected and recognized by a person with a normal sense of smell. These regulations do not specify how the odorant level should be determined. However, since the requirement is related to smell, the level should be determined by an olfactory method. There are two odorant monitoring methods commonly used by gas companies, the olfactory (odorometer) and the instrumentation (gas chromatograph) methods. The instrument method provides only quantitative results, which somehow must be related to an olfactory response. This paper discusses these methods.

Oudman, P. (Canada Western Natural Gas Co. Ltd., Calgary, Alberta (Canada))

1993-12-01

422

Method and apparatus for improving acceleration in a multi-shaft gas turbine engine  

Microsoft Academic Search

A method is described for improving the acceleration of a free turbine, gas turbine engine from a minimum power condition to a maximum power condition. The gas turbine engine is provided with a diaphragm bleed valve means having a first chamber means and a second chamber means defined by a diaphragm, the first valve chamber means communicating with the compressor

Blizzard

1986-01-01

423

Aqueous Extraction-Headspace/Gas Chromatographic Method for Determination of Volatile Organic Compounds in Soils.  

National Technical Information Service (NTIS)

This study compares aqueous extraction-headspace/Gas Chromatography (GC) and the EPA SW-846 purge-and-trap-gas chromatography/mass spectrometry(Method 8240)for the determination of four common Volatile Organic Compounds (VOCs) in soils. Comparisons were m...

A. D. Hewitt P. H. Miyares D. C. Leggett T. F. Jenkins

1992-01-01

424

Disordered magnetic lattice gas: Formulation by the method of the distribution function  

Microsoft Academic Search

A spin-1 model of a disordered magnetic lattice gas with magnetic and nonmagnetic interactions is presented as an extension of the magnetic gas introduced in the previous paper. A formulation using the method of the distribution functions is given. The concept of an effective potential is introduced along with the usual effective field in order to describe this system. Integral

S. Inawashiro; N. E. Frankel; C. J. Thompson

1981-01-01

425

Piecewise continuous distribution function method in the theory of wave disturbances of inhomogeneous gas  

Microsoft Academic Search

The system of hydrodynamic-type equations for a stratified gas in gravity field is derived from BGK equation by method of piecewise continuous distribution function. The obtained system of the equations generalizes the Navier–Stokes one at arbitrary Knudsen numbers. The problem of a wave disturbance propagation in a rarefied gas is explored. The verification of the model is made for a

D. A. Vereshchagin; S. B. Leble; M. A. Solovchuk

2006-01-01

426

Piecewise continuous distribution function method in the theory of wave disturbances of inhomogeneous gas  

Microsoft Academic Search

The system of hydrodynamic-type equations for a stratified gas in gravity field is derived from BGK equation by method of piecewise continuous distribution function. The obtained system of the equations generalizes the Navier Stokes one at arbitrary Knudsen numbers. The problem of a wave disturbance propagation in a rarefied gas is explored. The verification of the model is made for

D. A. Vereshchagin; S. B. Leble; M. A. Solovchuk

2006-01-01

427

A method of quantitative risk assessment for transmission pipeline carrying natural gas  

Microsoft Academic Search

Regulatory authorities in many countries are moving away from prescriptive approaches for keeping natural gas pipelines safe. As an alternative, risk management based on a quantitative assessment is being considered to improve the level of safety. This paper focuses on the development of a simplified method for the quantitative risk assessment for natural gas pipelines and introduces parameters of fatal

Young-Do Jo; Bum Jong Ahn

2005-01-01

428

Pollution control apparatus and method. [particle removal from off-gas streams  

Microsoft Academic Search

Apparatus operating at low pressure drop and low initial velocity for removing pollutants down to submicron sizes from gas streams comprising a nozzle means accelerating the gas flow to about four times its entering velocity into a large expansion chamber having an impinger area for removal of pollutants. This is a method of removing pollutants down to sub-micron size at

Pircon

1975-01-01

429

Methods of Gas Phase Capture of Iodine from Fuel Reprocessing Off-Gas: A Literature Survey.  

National Technical Information Service (NTIS)

A literature survey was conducted to collect information and summarize the methods available to capture iodine from fuel reprocessing off-gases. Techniques were categorized as either wet scrubbing or solid adsorbent methods, and each method was generally ...

D. R. Haefner T. J. Tranter

2007-01-01

430

Fusion, mechanical joining methods pros, cons--Part 2. [Natural gas pipelines use of mechanical and fusion joints  

Microsoft Academic Search

Two basic techniques accepted by gas distribution utility companies for joining polyethylene pipe underground are fusion methods and mechanical joining. Washington Gas Light Co., uses the fusion methods for the most part and uses mechanical joints for repair and final tie-ins where fusion methods are impractical or impossible to use. Fusion methods used by gas industry users of plastic pipe

Gunther

1993-01-01

431

Method for converting hydrocarbon fuel into hydrogen gas and carbon dioxide  

DOEpatents

A method for converting hydrocarbon fuel into hydrogen gas and carbon dioxide within a reformer 10 is disclosed. According to the method, a stream including an oxygen-containing gas is directed adjacent to a first vessel 18 and the oxygen-containing gas is heated. A stream including unburned fuel is introduced into the oxygen-containing gas stream to form a mixture including oxygen-containing gas and fuel. The mixture of oxygen-containing gas and unburned fuel is directed tangentially into a partial oxidation reaction zone 24 within the first vessel 18. The mixture of oxygen-containing gas and fuel is further directed through the partial oxidation reaction zone 24 to produce a heated reformate stream including hydrogen gas and carbon monoxide. Steam may also be mixed with the oxygen-containing gas and fuel, and the reformate stream from the partial oxidation reaction zone 24 directed into a steam reforming zone 26. High- and low-temperature shift reaction zones 64,76 may be employed for further fuel processing.

Clawson, Lawrence G. (Dover, MA); Mitchell, William L. (Belmont, MA); Bentley, Jeffrey M. (Westford, MA); Thijssen, Johannes H. J. (Cambridge, MA)

2000-01-01

432

Influence of changes in atmospheric pressure on evaporation rates of low-loss helium cryostats  

Microsoft Academic Search

Experimental equipment for pressure control and evaporation rate measurement of a low-loss helium cryostat is described. The dependence of the helium gas outflow on the linearly varying pressure is presented for an NMR cryostat. The variations in measured helium evaporation rate were significantly high during experiments simulating usual atmospheric pressure changes. The measured quantities are compared to those evaluated by

P. Hanzelka; V. Musilová

1995-01-01

433

Advanced models for droplet heating and evaporation: Effect on the autoignition of diesel fuel sprays  

Microsoft Academic Search

Liquid and gas phase models for fuel droplet heating and evaporation, suitable for implementation into CFD codes with a view to modelling the processes in Diesel engines, are reviewed. To describe properties of ?hot? diesel fuel sprays, new sub-models for spray breakup, droplet heating and evaporation and Shell autoignition were implemented into the KIVA II CFD code. To validate these

S. S. Sazhin; C. Crua; S. B. Martynov; T. Kristyadi; M. R. Heikal

2007-01-01

434

Evaporation of a thin film: diffusion of the vapour and Marangoni instabilities  

Microsoft Academic Search

The stability of an evaporating thin liquid film on a solid substrate is investigated within lubrication theory. The heat flux due to evaporation induces thermal gradients; the generated Marangoni stresses are accounted for. Assuming the gas phase at rest, the dynamics of the vapour reduces to diffusion. The boundary condition at the interface couples transfer from the liquid to its

Eric Sultan; Arezki Boudaoud; Martine Ben Amar

2005-01-01

435

Method for the recovery of clean pyrolysis off-gas and a rotary recycling means therefor  

SciTech Connect

A method and apparatus for stripping entrained organic vapor and solid particulate matter from a pyrolytic off-gas stream is disclosed. The off-gas is introduced at the top of a conical chamber having a variable speed ''squirrel cage'' rotor at its top. The wet, dirty, off-gas is drawn into the rotor from below and impinged upon the chamber walls which causes part of the organic vapor to condense and flow to the chamber bottom, thereby cleaning the chamber walls. A portion of the impinged gas is recirculated through the rotor while the remainder exits at the chamber bottom. The ratio of recycled gas to through gas is controlled by the speed of the rotor. Heating and cooling coils on the chamber walls are operable to control the rate of condensation.

Elston, L.W.; Hurst, D.R.

1981-07-14

436

Entropy localization and extensivity in the semiclassical black hole evaporation  

Microsoft Academic Search

We aim to quantify the distribution of information in the Hawking radiation and inside the black hole in the semiclassical evaporation process. The structure quantum field theory forces to consider a shared information between two different regions of space-time. Using this tool, we show that the entropy of a thermal gas at the Unruh temperature underestimates the actual amount of

H. Casini

2007-01-01

437

Modelling evaporation fronts with reactive Riemann solvers  

Microsoft Academic Search

This work deals with the modelling of permeable fronts and the building of a numerical method allowing the multi-dimensional propagation of such fronts. A particular attention is given to evaporation waves that appear in cavitating systems. These ones are considered as discontinuities through which a non-equilibrium liquid turns to a liquid–vapor mixture at thermodynamic equilibrium. Such transformation occurs at finite

O.. Le Metayer; J.. Massoni; R.. Saurel

2005-01-01

438

Comparison study on qualitative and quantitative risk assessment methods for urban natural gas pipeline network.  

PubMed

In this paper, a qualitative and a quantitative risk assessment methods for urban natural gas pipeline network are proposed. The qualitative method is comprised of an index system, which includes a causation index, an inherent risk index, a consequence index and their corresponding weights. The quantitative method consists of a probability assessment, a consequences analysis and a risk evaluation. The outcome of the qualitative method is a qualitative risk value, and for quantitative method the outcomes are individual risk and social risk. In comparison with previous research, the qualitative method proposed in this paper is particularly suitable for urban natural gas pipeline network, and the quantitative method takes different consequences of accidents into consideration, such as toxic gas diffusion, jet flame, fire ball combustion and UVCE. Two sample urban natural gas pipeline networks are used to demonstrate these two methods. It is indicated that both of the two methods can be applied to practical application, and the choice of the methods depends on the actual basic data of the gas pipelines and the precision requirements of risk assessment. PMID:21402442

Han, Z Y; Weng, W G

2011-02-26

439

Evaporative cooling: effective latent heat of evaporation in relation to evaporation distance from the skin.  

PubMed

Calculation of evaporative heat loss is essential to heat balance calculations. Despite recognition that the value for latent heat of evaporation, used in these calculations, may not always reflect the real cooling benefit to the body, only limited quantitative data on this is available, which has found little use in recent literature. In this experiment a thermal manikin, (MTNW, Seattle, WA) was used to determine the effective cooling power of moisture evaporation. The manikin measures both heat loss and mass loss independently, allowing a direct calculation of an effective latent heat of evaporation (?eff). The location of the evaporation was varied: from the skin or from the underwear or from the outerwear. Outerwear of different permeabilities was used, and different numbers of layers were used. Tests took place in 20°C, 0.5 m/s at different humidities and were performed both dry and with a wet layer, allowing the breakdown of heat loss in dry and evaporative components. For evaporation from the skin, ?eff is close to the theoretical value (2,430 J/g) but starts to drop when more clothing is worn, e.g., by 11% for underwear and permeable coverall. When evaporation is from the underwear, ?eff reduction is 28% wearing a permeable outer. When evaporation is from the outermost layer only, the reduction exceeds 62% (no base layer), increasing toward 80% with more layers between skin and wet outerwear. In semi- and impermeable outerwear, the added effect of condensation in the clothing opposes this effect. A general formula for the calculation of ?eff was developed. PMID:23329814

Havenith, George; Bröde, Peter; den Hartog, Emiel; Kuklane, Kalev; Holmer, Ingvar; Rossi, Rene M; Richards, Mark; Farnworth, Brian; Wang, Xiaoxin

2013-01-17

440

Adaptive Instability Suppression Controls Method for Aircraft Gas Turbine Engine Combustors.  

National Technical Information Service (NTIS)

An adaptive controls method for instability suppression in gas turbine engine combustors has been developed and successfully tested with a realistic aircraft engine combustor rig. This testing was part of a program that demonstrated, for the first time, s...

C. T. Chang G. Kopasakis J. C. DeLaat

2008-01-01

441

Evaluation of Gas Chromatographic Methods for Analysis of Gasoline/Oxygenate Blends.  

National Technical Information Service (NTIS)

The selection/development of a standard gas chromatographic method for the determination of oxygenates in gasoline-oxygenate blends is in keeping with laboratory characterization and specification testing phase of the U.S. Army's alternate fuels program. ...

K. B. Jones S. M. Biela F. M. Newman

1981-01-01

442

In situ Repair Methods for Interior Gas Piping. Final Report, July 1991-January 1992.  

National Technical Information Service (NTIS)

There exists within the gas utility industry a need to develop better equipment and methods to perform inside-the-building inspection and maintenance tasks, particularly in concealed threaded black steel pipe (BSP) systems in multifamily buildings. The re...

L. Ystueta

1992-01-01

443

Note on Evaporation in Capillaries.  

National Technical Information Service (NTIS)

Factors are discussed which govern evaporation of liquid in small capillaries of greatly varying bore, such as might be encountered in porous media. If the escape of the vapor is relatively unobstructed, marked temperature gradients are found to be confin...

R. E. Meyer

1983-01-01

444

Study on Method of Ultrasonic Gas Temperature Measure Based on FPGA  

NASA Astrophysics Data System (ADS)

It is always a problem to measure instantaneous temperature of high-temperature and high-pressure gas. There is difficulty for the conventional method of measuring temperature to measure quickly and exactly, and the measuring precision is low, the ability of anti-jamming is bad, etc. So the article introduces a method of measuring burning gas temperature using ultrasonic based on Field-Programmable Gate Array (FPGA). The mathematic model of measuring temperature is built with the relation of velocity of ultrasonic transmitting and gas Kelvin in the ideal gas. The temperature can be figured out by measuring the difference of ultrasonic frequency ?f. FPGA is introduced and a high-precision data acquisition system based on digital phase-shift technology is designed. The feasibility of proposed above is confirmed more by measuring pressure of burning gas timely. Experimental result demonstrates that the error is less than 12.. and the precision is heightened to 0.8%.

Wen, S. H.; Xu, F. R.

2006-10-01

445

Quantitative Evaluation of the Matabolic Interactions between Trichloroethylene and 1,1-Dichloroethylene In vivo Using Gas Uptake Methods,  

National Technical Information Service (NTIS)

Quantitative Evaluation of the Metabolic Interactions between Trichloroethylene and 1,1-Dichloroethylene in Vivo Using Gas Uptake Methods. Gas uptake simulation methods were used to determine kinetic constants for trichloroethylene (TCE) and 1,1-dichloroe...

M. E. Anderson M. L. Gargas H. J. Clewell K. M. Severyn

1987-01-01

446

Statistical methods to monitor the West Valley off-gas system  

Microsoft Academic Search

The off-gas system for the ceramic melter operated at the West Valley Demonstration Project at West Valley, NY, is monitored during melter operation. A one-at-a-time method of monitoring the parameters of the off-gas system is not statistically sound. Therefore, multivariate statistical methods appropriate for the monitoring of many correlated parameters will be used. Monitoring a large number of parameters increases

Eggett

1990-01-01

447

A rapid gas chromatographic method for the determination of poly- ? -hydroxybutyric acid in microbial biomass  

Microsoft Academic Search

The gas chromatographic method for the determination of poly-ß-hydroxybutyric acid (PHB) consists of a mild acid or alkaline methanolysis of poly-ß-hydroxybutyric acid directly without previous extraction of PHB from the cells; this is followed by gas chromatography of the 3-hydroxybutyric acid methylester. The method is characterized by high accuracy and excellent reproducibility, permitting determinations as low as 10-5 g\\/l. Only

G. Braunegg; B. Sonnleitner; R. M. Lafferty

1978-01-01

448

Classical fields method for a relativistic interacting Bose gas  

SciTech Connect

We formulate a classical fields method for the description of relativistic interacting bosonic particles at nonzero temperatures. The method relies on the assumption that at low temperatures the Bose field can be described by a c-number function. We discuss a very important role of the cutoff momentum which divides the field into a dominant classical part and a small quantum correction. We illustrate the method by studying the thermodynamics of a relativistic Bose field which is governed by the Klein-Gordon equation with a {lambda}{psi}{sup 4} term responsible for the interactions.

Witkowska, Emilia [Institute of Physics, Polish Academy of Sciences, al. Lotnikow, 02-668 Warsaw (Poland); Zin, Pawel [Institute for Theoretical Physics, Warsaw University, ul. Hoza 69, 00-681 Warsaw (Poland); Soltan Institute for Nuclear Studies, ul. Hoza 69, 00-681 Warsaw (Poland); Gajda, Mariusz [Institute of Physics, Polish Academy of Sciences, al. Lotnikow, 02-668 Warsaw (Poland); Faculty of Mathematics and Natural Sciences, College of Sciences, Cardinal's Stefan Wyszynski University, ul. Dewajtis, 01-815 Warsaw (Poland)

2009-01-15

449

METAL-ION ABSORPTION IN CONDUCTIVELY EVAPORATING CLOUDS  

SciTech Connect

We present computations of the ionization structure and metal-absorption properties of thermally conductive interface layers that surround evaporating warm spherical clouds embedded in a hot medium. We rely on the analytical steady-state formalism of Dalton and Balbus to calculate the temperature profile in the evaporating gas, and we explicitly solve the time-dependent ionization equations for H, He, C, N, O, Si, and S in the conductive interface. We include photoionization by an external field. We estimate how departures from equilibrium ionization affect the resonance-line cooling efficiencies in the evaporating gas, and determine the conditions for which radiative losses may be neglected in the solution for the evaporation dynamics and temperature profile. Our results indicate that nonequilibrium cooling significantly increases the value of the saturation parameter {sigma}{sub 0} at which radiative losses begin to affect the flow dynamics. As applications, we calculate the ion fractions and projected column densities arising in the evaporating layers surrounding dwarf-galaxy-scale objects that are also photoionized by metagalactic radiation. We compare our results to the UV metal-absorption column densities observed in local highly ionized metal absorbers, located in the Galactic corona or intergalactic medium. Conductive interfaces significantly enhance the formation of high ions such as C{sup 3+}, N{sup 4+}, and O{sup 5+} relative to purely photoionized clouds, especially for clouds embedded in a high-pressure corona. However, the enhanced columns are still too low to account for the O VI columns ({approx}10{sup 14} cm{sup -2}) observed in the local high-velocity metal-ion absorbers. We find that column densities larger than {approx}10{sup 13} cm{sup -2} cannot be produced in evaporating clouds. Our results do support the conclusion of Savage and Lehner that absorption due to evaporating O VI likely occurs in the local interstellar medium, with characteristic columns of {approx}10{sup 13} cm{sup -2}.

Gnat, Orly [Theoretical Astrophysics, California Institute of Technology, MC 350-17, Pasadena, CA 91125 (United States); Sternberg, Amiel [School of Physics and Astronomy and the Wise Observatory, Beverly and Raymond Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 69978 (Israel); McKee, Christopher F., E-mail: orlyg@tapir.caltech.ed [Departments of Physics and Astronomy, University of California, Berkeley, Campbell Hall, Berkeley, CA 94720-7304 (United States)

2010-08-01

450

Metal-ion Absorption in Conductively Evaporating Clouds  

NASA Astrophysics Data System (ADS)

We present computations of the ionization structure and metal-absorption properties of thermally conductive interface layers that surround evaporating warm spherical clouds embedded in a hot medium. We rely on the analytical steady-state formalism of Dalton and Balbus to calculate the temperature profile in the evaporating gas, and we explicitly solve the time-dependent ionization equations for H, He, C, N, O, Si, and S in the conductive interface. We include photoionization by an external field. We estimate how departures from equilibrium ionization affect the resonance-line cooling efficiencies in the evaporating gas, and determine the conditions for which radiative losses may be neglected in the solution for the evaporation dynamics and temperature profile. Our results indicate that nonequilibrium cooling significantly increases the value of the saturation parameter ?0 at which radiative losses begin to affect the flow dynamics. As applications, we calculate the ion fractions and projected column densities arising in the evaporating layers surrounding dwarf-galaxy-scale objects that are also photoionized by metagalactic radiation. We compare our results to the UV metal-absorption column densities observed in local highly ionized metal absorbers, located in the Galactic corona or intergalactic medium. Conductive interfaces significantly enhance the formation of high ions such as C3+, N4+, and O5+ relative to purely photoionized clouds, especially for clouds embedded in a high-pressure corona. However, the enhanced columns are still too low to account for the O VI columns (~1014 cm-2) observed in the local high-velocity metal-ion absorbers. We find that column densities larger than ~1013 cm-2 cannot be produced in evaporating clouds. Our results do support the conclusion of Savage and Lehner that absorption due to evaporating O VI likely occurs in the local interstellar medium, with characteristic columns of ~1013 cm-2.

Gnat, Orly; Sternberg, Amiel; McKee, Christopher F.

2010-08-01

451

Methods for liquid filling inflated lungs and measuring any retained gas.  

PubMed

A method is described for liquid filling lungs without collapse by ventilating them on CO2 and then absorbing this gas with isotonic Tris buffer solution. The gas retained in each of 16 liquid-filled lungs has been measured by their compression in a dilatometer and averages 0.13% of lung volume. The liquid filling method has the advantage that it can be used either for lungs in situ or excised; total elimination of any retained gas, if desired, can be ensured by subsequent compression to 8.3 ATA for 10 min. PMID:6794206

Hills, B A; Barrow, R E

1981-09-01

452

Theoretical investigation of the injection and evaporation of water in a hydrogen/oxygen steam generator  

NASA Astrophysics Data System (ADS)

Water is injected into the gas stream for the purpose of cooling the reaction products resulting from the stochiometric combustion of hydrogen with oxygen. The penetration of the jet decisively influences the temperature profile across the flow cross section in the water vapor. The penetration of the water jet into the stream is calculated using the jet shedding model and compared with the garden hose model. Models for the evaporation of water droplets in superheated steam are developed for calculating the evaporation paths. The parameters which influence the injection and evaporation process are subjected to variation and their effects in the evaporation paths are analyzed.

Beer, Stefan

1991-07-01

453

Methods of Gas Phase Capture of Iodine from Fuel Reprocessing Off-Gas: A Literature Survey  

SciTech Connect

A literature survey was conducted to collect information and summarize the methods available to capture iodine from fuel reprocessing off-gases. Techniques were categorized as either wet scrubbing or solid adsorbent methods, and each method was generally described as it might be used under reprocessing conditions. Decontamination factors are quoted only to give a rough indication of the effectiveness of the method. No attempt is made to identify a preferred capture method at this time, although activities are proposed that would provide a consistent baseline that would aid in evaluating technologies.

Daryl Haefner

2007-02-01

454

Development of liquid and gas chromatographic methods for the determination of water.  

National Technical Information Service (NTIS)

Two liquid chromatographic (LC) methods and one gas chromatographic (GC) method for the determination of water are developed. In the LC methods, water in various analytical samples is separated from the sample matrices on either a single cation-exchange c...

J. Chen

1991-01-01

455

From evaporating pans to transpiring plants (John Dalton Medal Lecture)  

NASA Astrophysics Data System (ADS)

The name of the original inventor of irrigated agriculture is lost to antiquity. Nevertheless, one can perhaps imagine an inquisitive desert inhabitant noting the greener vegetation along a watercourse and putting two and two together. Once water was being supplied and food was being produced it would be natural to ask a further question: how much water can we put on? No doubt much experience was gained down through the ages, but again, one can readily imagine someone inverting a rain gauge, filling it with water and measuring how fast the water evaporated. The inverted rain gauge measures the demand for water by the atmosphere. We call it the evaporative demand. I do not know if this is what actually happened but it sure makes an interesting start to a talk. Evaporation pans are basically inverted rain gauges. The rain gauge and evaporation pan measure the supply and demand respectively and these instruments are the workhorses of agricultural meteorology. Rain gauges are well known. Evaporation pans are lesser known but are in widespread use and are a key part of several national standardized meteorological networks. Many more pans are used for things like scheduling irrigation on farms or estimating evaporation from lakes. Analysis of the long records now available from standardized networks has revealed an interesting phenomenon, i.e., pan evaporation has increased in some places and decreased in other but when averaged over large numbers of pans there has been a steady decline. These independent reports from, for example, the US, Russia, China, India, Thailand, are replicated in the southern hemisphere in, for example, Australia, New Zealand and South Africa. One often hears the statement that because the earth is expected to warm with increasing greenhouse gas emissions then it follows that water will evaporate faster. The pan evaporation observations show that this widely held expectation is wrong. When expectations disagree with observations, it is the observations that win. That is the basis of science. In this Dalton Medal lecture we first examine pan evaporation observations and show why pan evaporation has declined. Armed with that knowledge we then investigate the consequences for plant water use and how this is directly coupled to the catchment water balance.

Roderick, Michael

2013-04-01

456

Production of stable tellurium evaporated targets  

NASA Astrophysics Data System (ADS)

Due to the low melting point of tellurium metal, self-supporting Te targets degrade quickly when exposed to particle beams. This situation is greatly improved if the tellurium material is evaporated onto C foil backings. Elastic scattering in target and backing layers broadens the Te peak, making measurements difficult, while too little material reduces the reaction rate. Therefore, it is necessary to optimize the target thickness. Evaporated metallic and oxide Te targets were prepared at Argonne National Laboratory by vacuum deposition from a resistively heated source boat. The stability of the targets was then tested by exposing them to a varying intensity alpha beam with an energy range from 17 to 27 MeV using the FN Tandem Van de Graaff accelerator at the University of Notre Dame. Optimal target thicknesses and beam currents were then obtained for p-process experiments. A description of the apparatus and production method will be presented.

Greene, John P.; Palumbo, Annalia; Tan, Wanpeng; Görres, Joachim; Wiescher, Michael C.

2008-06-01

457

An Experimental and Modeling Study of Evaporation from Bare Soils Subjected to Natural Boundary Conditions at the Land-Atmospheric Interface  

NASA Astrophysics Data System (ADS)

Bare soil evaporation is a key process for water exchange between the land and the atmosphere and an important component of the water balance in semiarid and arid regions. However, there is no agreement on the best methodology to determine evaporation under different boundary conditions. Because it is difficult to measure evaporation from soil,with the exception of using lysimeters, numerous formulations have been proposed to establish a relationship between the rate of evaporation and soil moisture and/or soil temperature and thermal properties. Different formulations vary in how they partition available energy and include, among others, a classical bulk aerodynamic formulation which requires knowledge of the relative humidity at the soil surface and a more non-traditional heat balance method which requires knowledge of soil temperature and soil thermal properties. A need exists to systematically compare existing methods to experimental data under highly controlled conditions not achievable in the field. The goal of this work is to perform controlled experiments under transient conditions of soil moisture, temperature and wind at the land/atmospheric interface to test different conceptual and mathematical formulations for evaporation rate estimates and to develop appropriate numerical models to be used in simulations. In this study, to better understand the coupled water-vapor-heat flow processes in the shallow subsurface near the land surface, we modified a previously developed theory that allows non-equilibrium liquid/gas phase change with gas phase vapor diffusion to better account for evaporation under dry soil conditions. This theory was used to compare estimates of evaporation based on different formulations of the bulk aerodynamic and heat balance methods. In order to experimentally validate the numerical formulations/code, we performed a series of two-dimensional physical model experiments under varying boundary conditions using test sand for which the hydraulic and thermal properties were well characterized. We developed a unique two dimensional cell apparatus equipped with a network of sensors for automated and continuous monitoring of soil moisture, soil and air temperature and relative humidity, and wind velocity. Precision data under well-controlled transient heat and wind boundary conditions was generated. Results from numerical simulations were compared with experimental data. Results demonstrate the importance of properly characterizing soil thermal properties and accounting for dry soil conditions to properly estimate evaporation. Initial comparisons of various formulations of evaporation demonstrate the need for joint evaluation of heat and mass transfer for better modeling accuracy. Detailed comparisons are still underway. This knowledge is applicable to many current hydrologic and environmental problems to include climate modeling and the simulation of contaminant transport and volatilization in the shallow subsurface.

Smits, K. M.; Ngo, V. V.; Cihan, A.; Sakaki, T.; Illangasekare, T. H.; kathleen m smits

2011-12-01

458

Horizontal natural gas storage caverns and methods for producing same  

Microsoft Academic Search

The invention provides caverns and methods for producing caverns in bedded salt deposits for the storage of materials that are not solvents for salt. The contemplated salt deposits are of the bedded, non-domed variety, more particularly salt found in layered formations that are sufficiently thick to enable the production of commercially usefully sized caverns completely encompassed by walls of salt

1995-01-01

459

Control method for turbocharged diesel engines having exhaust gas recirculation  

DOEpatents

A method of controlling the airflow into a compression ignition engine having an EGR and a VGT. The control strategy includes the steps of generating desired EGR and VGT turbine mass flow rates as a function of the desired and measured compressor mass airflow values and exhaust manifold pressure values. The desired compressor mass airflow and exhaust manifold pressure values are generated as a function of the operator-requested fueling rate and engine speed. The EGR and VGT turbine mass flow rates are then inverted to corresponding EGR and VGT actuator positions to achieve the desired compressor mass airflow rate and exhaust manifold pressure. The control strategy also includes a method of estimating the intake manifold pressure used in generating the EGR valve and VGT turbine positions.

Kolmanovsky, Ilya V. (Ypsilanti, MI); Jankovic, Mrdjan J (Birmingham, MI); Jankovic, Miroslava (Birmingham, MI)

2000-03-14

460

Linear nozzle with tailored gas plumes and method  

SciTech Connect

There is claimed a method for depositing fluid material from a linear nozzle in a substantially uniform manner across and along a surface. The method includes directing gaseous medium through said nozzle to provide a gaseous stream at the nozzle exit that entrains fluid material supplied to the nozzle, said gaseous stream being provided with a velocity profile across the nozzle width that compensates for the gaseous medium's tendency to assume an axisymmetric configuration after leaving the nozzle and before reaching the surface. There is also claimed a nozzle divided into respective side-by-side zones, or preferably chambers, through which a gaseous stream can be delivered in various velocity profiles across the width of said nozzle to compensate for the tendency of this gaseous medium to assume an axisymmetric configuration.

Leon, David D. (Murrysville, PA); Kozarek, Robert L. (Apollo, PA); Mansour, Adel (Mentor, OH); Chigier, Norman (Pittsburgh, PA)

1999-01-01