WorldWideScience
1

The response of quartz crystals coated with thin fatty acid film to organic gases  

Energy Technology Data Exchange (ETDEWEB)

We tried to apply a quartz crystal as a sensor by using the resonant frequency and the resistance properties of quartz crystals. Four kinds of fatty acids that have the same head groups were coated on the surfaces of the quartz crystals, and the shift of the resonant frequency and the resistance were observed based on the lengths of the tail groups. Myristic acid (C{sub 14}), palmitic acid (C{sub 16}), stearic acid (C{sub 18}), and arachidic acid (C{sub 20}) were deposited on the surfaces of quartz crystals by using the Langmuir-Blodgett (LB) method. As a result, the resonant frequency change was more sensitive to high molecular-weight fatty acids than to low molecular-weight ones. We also observed the effect of temperature on stearic acid LB films, and the response properties of quartz crystals coated with stearic-acid LB films to organic ...

1999-07-01

2

Tritium contamination and decontamination study on materials for ITER remote handling equipment  

Energy Technology Data Exchange (ETDEWEB)

Several materials, lenses, dry bearings and cables were exposed to a tritiated moisture environment to study the behavior of tritium contamination on candidate materials for ITER remote handling equipment. To optimize the tritium removal procedure, decontamination experiments using a gas purge with three different moisture concentrations were also performed. The surface tritium concentrations of CeO{sub 2} containing alkaline barium glass (NB), CeO{sub 2} containing lead glass (LX) and synthetic quartz (Quartz) after the exposure experiments were 7.80, 10.94 and 0.67 Bq/cm{sup 2}, respectively. It was found that the tritium concentration was influenced by the compositions of the materials. The concentrations of tritium on type 831 (solid lubrication material: graphite) and type 237 (solid lubrication material: tungsten disulfate) dry bearings after the exposure experiments were ...

2001-09-01

3

Tritium contamination and decontamination study on materials for ITER remote handling equipment  

International Nuclear Information System (INIS)

Several materials, lenses, dry bearings and cables were exposed to a tritiated moisture environment to study the behavior of tritium contamination on candidate materials for ITER remote handling equipment. To optimize the tritium removal procedure, decontamination experiments using a gas purge with three different moisture concentrations were also performed. The surface tritium concentrations of CeO_2 containing alkaline barium glass (NB), CeO_2 containing lead glass (LX) and synthetic quartz (Quartz) after the exposure experiments were 7.80, 10.94 and 0.67 Bq/cm"2, respectively. It was found that the tritium concentration was influenced by the compositions of the materials. The concentrations of tritium on type 831 (solid lubrication material: graphite) and type 237 (solid lubrication material: tungsten disulfate) dry bearings after the exposure experiments were 89.80 and 31.78 ...

2001-09-01

4

CERES BDS Quality Summaries - Atmospheric Science Data Center - NASA  

Science.gov (United States)

Nov 18, 2010 ... Roughly speaking, the fidelity interval we quote is a "3 sigma" value. ... surface of the foremost quartz filter which is then chemically altered by ... ( CERES) scanner point accuracy using a coastline detection system", ...

5

Nanoparticles and their tailoring with laser light  

Energy Technology Data Exchange (ETDEWEB)

Monodisperse noble metal nanoparticles are of tremendous interest for numerous applications, such as surface-enhanced Raman spectroscopy, catalysis or biosensing. However, preparation of monodisperse metal nanoparticles is still a challenging task, because typical preparation methods yield nanoparticle ensembles with broad shape and/or size distributions. To overcome this drawback, tailoring of metal nanoparticles with laser light has been developed, which is based on the pronounced shape- and size-dependent optical properties of metal nanoparticles. I will demonstrate that nanoparticle tailoring with ns-pulsed laser light is a suitable method to prepare nanoparticle ensembles with a narrow shape and/or size distribution. While irradiation with ns-pulsed laser light during nanoparticle growth permits a precise shape tailoring, post-grown irradiation allows a size tailoring. For example, the initial broad Gaussian size distribution of silver nanoparticles on ...

2009-07-15

6

Simple method for the high-temperature isolation of /sup 111/In from silver  

Energy Technology Data Exchange (ETDEWEB)

A method is proposed for the quantitative high-temperature isolation of /sup 111/In from silver irradiated by ..cap alpha..-particles into a gas phase containing a mixture of HCl and H/sub 2/O with a total pressure of about 3 Pa for these gases. It is shown that the indium evolved into the gas phase probably occurs in the form of at least three compounds, viz.., the trichloride, monochloride, and oxychloride, which have adsorption temperatures on quartz of around 385, 475, and 655 K, respectively. All these compounds are readily washed from the surface of quartz apparatus by a weak (0.05 M) solution of hydrochloric acid.

1987-07-01

8

A Review of Test Medium Contamination Effects on Test ...  

Science.gov (United States)

... solid particle contamination. Solid particulate impact is a good mechanism for surface heat transfer augmentation. The aug ...

1998-01-01

9

Laser applications. Final report  

Energy Technology Data Exchange (ETDEWEB)

Processes were developed that use lasers as manufacturing tools. These processes were stripping of insulation from cables and wires, machining of quartz, microdrilling and welding of reflective metals, and precision alignment of curved surfaces before machining. A technological basis also was formed which resulted in a process for automatic surface inspection of parts and aided development of machining processes for Kevlar parts.

1980-07-01

10

Behavior of catalyst and mineral matter in coal liquefaction; Sekitan ekika hannochu no kobusshitsu to shokubai no kyodo  

Energy Technology Data Exchange (ETDEWEB)

Mineral matter in coals is important in various senses for coal liquefaction. It is possible that the catalytic activity is affected by the interaction between catalyst and mineral matter. Iron-based catalyst forms pyrrhotite in the process of liquefaction, but the interaction between it and mineral matter is not known in detail. In this study, the interaction between mineral matter and catalyst and the selective reaction between them were investigated. Tanito Harum coal was used for this study. This coal contains a slight amount of siderite and jarosite besides pyrite as iron compounds. Liquefaction samples were obtained from the 1 t/d NEDOL process PSU. The solid deposits in the reactor mainly contained pyrrhotite and quartz. A slight amount of kaolinite was observed, and pyrite was little remained. It was found that the catalyst (pyrrhotite) often coexisted with quartz, clay and calcite. 8 figs., 2 tabs.

1996-10-28

11

An example of alkalization of SiO{sub 2} in a blast furnace coke  

Science.gov (United States)

Scanning electron microscopy and an electron-microprobe analysis of a sample of blast furnace (BF) coke have revealed alkalization (5.64 wt % Na{sub 2}O + K{sub 2}O) and Al saturation (17.28 wt % Al{sub 2}O{sub 3}) of SiO{sub 2} by BF gases. The K/Na{sub at} value of 1.15 in the new phase (alteration zone) reflects close atomic proportions of the elements and suggests that the abilities to incorporate K and Na during the process are almost equal. This Al saturation and alkalization of SiO{sub 2} indicates an active role for Al along with alkali metals in BF gases. The average width of the altered area in the SiO{sub 2} grain is about 10 m, which suggests that SiO{sub 2} particles of that size can be transformed fully to the new phase, provided that at least one of their faces is open to an external pore (surface of the coke) or internal pore with circulating BF gases. The grains that exceed 10 {mu}m can only be partly altered, which means that smaller SiO{sub 2} ...

2007-09-15

13

Heat transfer in boiling liquified gas  

Energy Technology Data Exchange (ETDEWEB)

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

1980-09-23

14

Erosion of a model rosin-based marine antifouling paint binder as studied with quartz crystal microbalance with dissipation monitoring (QCM-D) and ellipsometry  

British Library Electronic Table of Contents (United Kingdom)

In this study two surface sensitive methods, i.e. quartz crystal microbalance with dissipation monitoring (QCM-D) and ellipsometry, were used for erosion measurements of a rosin-based marine antifouling paint binder. Thin films of the binder were applied on sensor surfaces by the means of spin-coating and the effect of water velocity over the paint film, water temperature or ionic strength on erosion was investigated. Both the acoustic QCM-D model and the optical ellipsometry model gave comparable erosion results. The initial 2-50nm rapid erosion of the top layer was followed by steady-state erosion rate until end of experiment. For example, the steady-state erosion rate was 12nm/24h in artificial seawater at 23degreeC and with a flow of 200ml/min over the paint surface as measured with QC...

2008-01-01

15

A simple dynamic model for solid transport in rotary dryers  

Energy Technology Data Exchange (ETDEWEB)

The solid particle movement in a rotary drum plays an important role in drying processes. The solid distribution in the drum affects the amount of contact surface between the solid and the gas. The retention time of solids influences the time particles can stay in contact with the gas in order to transfer heat and mass. Any heat and mass transfer model for a solid particle dryer must be able to predict solid flowrate and solid hold-up. There have been several reports in the literature regarding the modeling aspects of solid transport in dryers. If the model is developed for model-based control, it must be simple and yet represent dynamics of the system accurately. This paper addresses solid motion modeling and the effects of different variables involved in ...

2000-05-01

16

Direct denitration and recycling of PFBR MOX liquid waste from dissolution test using microwave heating method  

International Nuclear Information System (INIS)

Full text: Dissolution test (DT) is one of the important specifications of PFBR MOX fuel. It is a macro homogeneity test used to ascertain that the dissolution of spent fuel will be easier during reprocessing. The DT specification limit for PFBR MOX fuel is ? 1.0 wt.% residue of the whole pellet when it is dissolved in HNO3 under reflux conditions. For this test, sintered MOX pellet is dissolved in reflux condition in 60 ml of 12M HNO3 for 10 hours. This test is carried out for each batch and during complete MOX campaign a lot of MOX waste in liquid form is being generated. This liquid waste is in clean form and U and Pu is required to be recovered from the clean waste. Different methods like direct denitration, precipitation and solvent extraction are available but either the product is not of good quality for pelletization or secondary liquid wastes are generated. Microwave denitration is a faster and cleaner method which has different heat transfer mechanism and temperature profile ...

2010-11-24

17

Gravity settling  

Science.gov (United States)

Solids are separated from a liquid in a gravity settler provided with inclined solid intercepting surfaces to intercept the solid settling path to coalesce the solids and increase the settling rate. The intercepting surfaces are inverted V-shaped plates, each formed from first and second downwardly inclined upwardly curved intersecting conical sections having their apices at the vessel wall.

1979-01-01

18

Transport effect on He II film under conditions of weak interaction with the substrate  

Energy Technology Data Exchange (ETDEWEB)

The properties of a helium film on the surface of solid parahydrogen are investigated. It is shown that wetting of the solid hydrogen by the liquid helium occurs. The transport velocities along the He II film on the solid parahydrogen surface are measured in broad temperature, film height, and level difference ranges. It is shown that the transport velocity in this case has the least value as compared with its value on other substrates. The thickness of the helium-saturated film is determined on the solid hydrogen surface on the basis of the data obtained, and the value is in good agreement with the results of a computation performed within the framework of the Frenkel' theory.

1980-10-01

19

A simple model for explosives formulation  

Energy Technology Data Exchange (ETDEWEB)

A simple model based on surface chemistry is developed, based an simple concepts of contact angle, wetting and spreading. Results of the modeling can be stated by two simplified rules of thumb'': (1) A liquid will spread on the surface of a solid if the surface tension of the liquid is lose than the surface free energy of the solid, and (2) The liquid having the surface tension nearest that of the solid will preferentially wet the surface of the solid. These two rules can then be used to define the parameters that constitute a process for formulating a plastic bonded explosive (PBX), which is a crystalline high-explosive material coated with a small amount of plastic polymeric material (the binder). The PBX then can be pressed to a high density, and machined to ...

1993-01-01

20

A simple model for explosives formulation  

Energy Technology Data Exchange (ETDEWEB)

A simple model based on surface chemistry is developed, based an simple concepts of contact angle, wetting and spreading. Results of the modeling can be stated by two simplified ``rules of thumb``: (1) A liquid will spread on the surface of a solid if the surface tension of the liquid is lose than the surface free energy of the solid, and (2) The liquid having the surface tension nearest that of the solid will preferentially wet the surface of the solid. These two rules can then be used to define the parameters that constitute a process for formulating a plastic bonded explosive (PBX), which is a crystalline high-explosive material coated with a small amount of plastic polymeric material (the binder). The PBX then can be pressed to a high density, and machined to a specific ...

1993-04-01

21

The anisotropic growth in amorphous materials and the latent track formation induced by energetic ion bombardment  

Energy Technology Data Exchange (ETDEWEB)

The thermal spike model has been successfully applied to track formation by swift heavy ions in insulators. Arguments are given supporting the assumption that the thermal spike mechanism is also valid for the anisotropic growth. The glass transition temperature is used as the main thermal parameter of the amorphous solids. Experimental results on the track formation in {alpha}-quartz and in crystalline Ni{sub 3}B and also on the anisotropic growth in Pyrex and Synsil glasses, in amorphous Pd{sub 80}Si{sub 20}, Ni{sub 3}B and Fe{sub 85}B{sub 15} are discussed. Good agreement is found with the predictions of the thermal spike model. (orig.).

1996-02-01

22

Quartz ceramics alloying  

International Nuclear Information System (INIS)

The following methods of quartz ceramics alloying were considered: alloying of initial quartz glass; introduction of alloying additive into water slip of quartz glass; porous materials impregnation with salt aqueous solutions and subsequent salt thermal decomposition with formation of stable oxides in pores of ceramics. Oxygen free compounds BN, SiB_4, SiC, Si_3N_4, REM oxides and transition metal oxides were used as alloying additives. Main properties of the materials and compositions obtained are presented.

24

Adsorption of argon on homogeneous graphitized thermal carbon black and heterogeneous carbon surface.  

Science.gov (United States)

In this paper we investigate the effects of surface mediation on the adsorption behavior of argon at different temperatures on homogeneous graphitized thermal carbon black and on heterogeneous nongraphitized carbon black surface. The grand canonical Monte Carlo (GCMC) simulation is used to study the adsorption, and its performance is tested against a number of experimental data on graphitized thermal carbon black (which is known to be highly homogeneous) that are available in the literature. The surface-mediation effect is shown to be essential in the correct description of the adsorption isotherm because without accounting for that effect the GCMC simulation results are always greater than the experimental data in the region where the monolayer is being completed. This is due to the overestimation of the fluid-fluid interaction between particles in the first layer close to the solid ...

2005-07-15

25

Spectroscopic investigation of the charge dynamics of heavy ions penetrating solid and gaseous targets  

Energy Technology Data Exchange (ETDEWEB)

This thesis presents the study of the slowing down process of fast heavy ions inside matter. In the framework of this research, the influence of the target density on the stopping process is investigated. Experiments on the interaction of {sup 48}Ca{sup 6+}-{sup 48}Ca{sup 10+} and {sup 26}Mg{sup 5+} ion beams with initial energies of 11.4 MeV/u and 5.9 MeV/u with solid and gaseous targets have been carried out. A novel diagnostic method, X-ray spectroscopy of K-shell projectile radiation, is used to determine the ion charge state in relation to its velocity during the penetration of fast heavy ions inside the stopping material. A spatially resolved analysis of the projectile and target radiation in solids is achieved for the first time. The application of low-density silica aerogels as stopping media provided a stretching of the ion stopping length by 20 - 100 times in comparison with solid quartz. The ...

2007-01-15

26

Solid state and materials research: metal-semiconductor interactions  

International Nuclear Information System (INIS)

This section of the report is concerned with the study of the metallisation, oxidation and doping of materials which are of importance to the micro-electronics industry. The Van de Graaff accelerator and radioactive tracers are used for studying surface and sub-surface behaviour of these materials.

27

Contact Line Pinning by Microfabricated Patterns: Effects of Microscale Topography  

UK PubMed Central (United Kingdom)

We study how the microscale topography of a solid surface affects the apparent advancing and receding angles at the contact line of a liquid drop pinned to this surface. Photolithographic methods...Full Text Available

2009-05-05

28

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

UK PubMed Central (United Kingdom)

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

1983-09-01

29

Cavity detection by the electric method: the 3-dimensional case  

Energy Technology Data Exchange (ETDEWEB)

In this paper the authors prove a uniqueness theorem for the electric detection of cavities in a three dimensional solid from Cauchy data measured on the surface. The cavities, finite in number, are assumed to be insulating. The surfaces of the cavities are assumed to be smooth on the complement of a set that is, in some sense, negligible. (orig.)

2004-02-01

30

TRITEX. A ferritic steel loop with Pb-15.8Li. Facility and operation  

Energy Technology Data Exchange (ETDEWEB)

TRITEX was a pumped loop with Pb-15.8Li, fabricated from steel 1.4922. In contact with the molten eutectic were also molybdenum, vanadium and armco-iron. The loop was originally designed to investigate tritium extraction using solid getter metals. Over the years the goal changed to the study of metals, corrosion products and purification of the eutectic mixture. Therefore many modifications were done. The first part of this report describes TRITEX. All parts were enclosed in thermoboxes for a homogeneous temperature. One test section was in an argon glove box and could be opened during operation. Other special equipment`s were: permeation membranes and liquid-metal-covergas-interfaces to study the transport of H{sub 2}, D{sub 2} and {sup 3}H, different purification devices, a quartz observation window to see the liquid metal surface, 4 different kinds of flow measurements, level indicators, freeze valves. The second part ...

1999-05-01

31

Comparison of four advanced oxidation processes for the removal of naphthenic acids from model oil sands process water  

British Library Electronic Table of Contents (United Kingdom)

Four advanced oxidation processes (UV/TiO2, UV/IO4^-, UV/S2O8^2^-, and UV/H2O2) were tested for their ability to mineralize naphthenic acids to inorganic carbon in a model oil sands process water containing high dissolved and suspended solids at pH values ranging from 8 to 12. A medium pressure mercury (Hg) lamp was used, and a Quartz immersion well surrounded the lamp. The treatment goal of 5mg/L naphthenic acids (3.4mg/L total organic carbon (TOC)) was achieved under four conditions: UV/S2O8^2^- (20mM) at pH 8 and 10, and UV/H2O2 (50mM) at pH 8 (all with the Quartz immersion well). Values of electrical energy required to meet the treatment goal were about equal for UV/S2O8^2^- (20mM) and UV/H2O2 (50mM) at pH 8, but three to four times larger for treatment by UV/S2O8^2^- (20mM) at pH 10. ...

2011-01-01

32

Efficiency of selective IR multiphoton dissociation of molecules in a pulsed gas-dynamic flow interacting with a solid surface  

International Nuclear Information System (INIS)

Isotopically selective IR multiphoton dissociation of molecules (SF_6, CF_3I) in a pulsed gas-dynamic flow interacting with a solid surface was studied for the first time. A noticeable (severalfold) increase in the yield of products (compared to excitation of molecules in an unperturbed flow) without a substantial decrease in the selectivity of the process was observed. Possible reasons for the effect are discussed. (laser applications and other topics in quantum electronics)

2000-08-31

33

The use of quartz patch pipettes for low noise single channel recording.  

UK PubMed Central (United Kingdom)

Quartz has a dissipation factor of approximately 10(-4), which is an order of magnitude less than that of the best glasses previously used to fabricate patch pipettes; it's dielectric constant of 3.8...Full Text Available

1993-10-01

34

A HREELS Investigation of Ethylene on Pt Model Catalysts  

Science.gov (United States)

... analyzer section for angle resolved measurements, and a thin film evaporator with a quartz crystal microbalance to measure the mass deposition. ...

1990-05-20

35

Understanding of the volatility of GeO/sub 2/ in the presence of WO/sub 2/  

Energy Technology Data Exchange (ETDEWEB)

The equilibria composition of the gaseous and the solid phase in the system GeO/sub 2//WO/sub 2/ is calculated with an improved thermodynamical program for temperatures 1100 < T < 1400 K and constant volume. By means of the results the experimental observed migration of GeO/sub 2/ in the presence of WO/sub 2/ in a temperature gradient T/sub 2/ ..-->.. T/sub 1/ (1200 ..-->.. 1100 K) in sealed evacuated silica tubes is due to a chemical transport with H/sub 2/ as the transporting agent. The H/sub 2/ is formed by H/sub 2/O which is desorbed by the quartz glass of the ampoules. The also observed volatility of WO/sub 2/ and its deposition in form of Ge/sub 0.75/W/sub 3/O/sub 9/ at the 'cold' end (T/sub 1/) of the tubes is performed by gaseous GeWO/sub 4/. The calculated and experimental transport rates are compared and discussed.

1983-08-01

36

Henry`s law gas-solid chromatography and correlations of virial coefficients for hydrocarbons, chlorofluorocarbons, ethers, and sulfur hexafluoride adsorbed onto carbon  

Energy Technology Data Exchange (ETDEWEB)

Gas-solid chromatography was used to determine the Henry`s law second gas-solid virial coefficients within the temperature range of 314--615 K for ethane, propane, butane, isobutane, pentane, hexane, heptane, chloromethane, dichloromethane, trichloromethane, tetrachloromethane, trichlorofluoromethane (Freon 11), chlorodifluoromethane (Freon 22), dichlorodifluoromethane (Freon 12), methyl ether, ethyl ether, and sulfur hexafluoride with Carbopack B, a microporous carbon adsorbent. The temperature dependence of the second gas-solid virial coefficients of these adsorbates was used in conjunction with analyses based on a graphical method, a single-surface numeric integration method, a single-surface analytic expression method, and a two-surface analytic expression method to determine the gas-solid interaction energies and other parameters. The ...

1995-07-01

37

Investigation of lubrication in natural joints by neutron reflectometry  

Energy Technology Data Exchange (ETDEWEB)

Despite their high medical relevance, the principles of lubrication in natural joints are still unclear. It is generally accepted, that the presence of hyaluronic acid (HA), the main component of the synovial liquid, plays an important role for the low friction observed. Furthermore, it is assumed that surface active lipids participate in the lubrication. Using a model system of lipid bilayers deposited on a polyelectrolyte (PE) cushion and in contact with HA solution, we started to investigate the effects of pressure and shear forces, as experienced by natural joints, on the internal structure of the SiO{sub 2}/PE/lipid/HA interface and the bulk HA solution by neutron reflectometry (NR), complemented by in situ ellipsometry and quartz crystal microbalance (QCM-D) measurements. Only on positively charged polyelectrolyte surfaces, the successful build-up of the model system could be demonstrated. By NR, the existence of an ...

2007-07-01

38

High resolution sequence stratigraphy, sedimentology, petrology and reservoir potentials of the Glauconitic member in Westerose and adjacent fields, Alberta, Canada  

Energy Technology Data Exchange (ETDEWEB)

This thesis studied the petrology and sequence stratigraphy of the Hoadley barrier, a Glauconitic member in the Westerose field in Alberta. The unit contains gas reserves in an extensive northeast-southwest trending marine complex. A high resolution sequence stratigraphic model was used to understand the facies development of the unit and the diagenetic pathway of the strata. Six high frequency sequences were identified within the Glauconitic member. Each are separated from one another by surfaces of incision or subaerial exposure which sometimes coincide with a flooding surface and erosion. This thesis provided a petrographic characterization and depositional history of each of the 6 sequences. Reservoir quality is developed within the relatively quartz-rich foreshore facies of the G2B sandstones. The G3 chert litharenite to sublitharenite sandstones are excellent gas producers because of their coarser grain size and ...

2002-07-01

39

Dependence of Energy Thresholds on Laser Radiation Wavelength in Initiation of Heavy Metal Azides  

CERN Document Server

The behavior of silver and lead azides (scaly and threadlike crystals, and compacted powders) in initiation of explosive decomposition by laser pulsed radiation has been investigated. Initiation energy thresholds in irradiation at wavelengths of 1064 nm, 532 nm, 354.7 nm, 266 nm corresponding to four laser radiation harmonics have been measured. Samples both uncovered and covered with a transparent dielectric (a quartz plate) with the compressive force of up to 0.5GPa were initiated. In the transparent spectral region (the first and second laser harmonics) of the heavy metal azide matrix the effect of covering the sample surface with a plate on initiation energy threshold was insignificant, whereas, in the region of bandgap absorption (the fourth harmonic) strong dependence of the initiation threshold on whether the surface under irradiation is uncovered or covered. The results obtained have been considered with the account ...

2010-01-01

40

Quartz fiber calorimetry and calorimeters  

CERN Document Server

Quartz fiber calorimetry is a technique the signal generation mechanism of which is based on the Cherenkov effect. In this article we try to give a comprehensive overview of the subject. We start with a general introduction to calorimetry where the basic elements that characterize the development of electromagnetic and hadronic showers are discussed. Then we describe in detail the operation principle and the properties of calorimeters equipped with quartz fibers. The main advantages of this type of calorimeters are the radiation hardness, the fast response and the compact detector dimensions, features that derive from the quartz material and the specific mechanism of operation. A section is devoted to presenting the quartz fiber calorimeters that have been built or planned to in various experiments to operate as centrality detectors, trigger detectors, luminosity monitors or general purpose very forward ...

2004-01-01

41

Quantification of order in the liquid at a solid-liquid interface by High-Resolution Transmission Electron Microscopy (HRTEM)  

Energy Technology Data Exchange (ETDEWEB)

A number of different theoretical approaches have been used to model to atomic structure and properties of solid-liquid interfaces. Most calculations indicate that ordering occurs in the first several layers of the liquid, adjacent to the crystal surface. In contrast to the numerous theoretical investigations, there have been no direct experimental observations of the atomic structure of a solid-liquid interface for comparison. Saka et al. examined solid-liquid interfaces in In and In-Sb at lattice-fringe resolution in the TEM, but their data do not reveal information about the atomic structure of the liquid phase. The purpose of this study is to determine the atomic structure of a solid-liquid interface using a highly viscous supercooled liquid, i.e., a crystal-amorphous interface.

1996-12-31

42

Quasi-elastic electron scattering by GaAs surface  

International Nuclear Information System (INIS)

Using the slow electrons spectrometer one can get information on the surface structure, its element composition, chemical bonds, adsorption phenomena, electron state density and surface oscillation. We have developed the methods and created the apparatus that makes it possible to investigate the electron backscattering by solid surface. We have studied the electron scattering by the polycrystalline and monocrystalline. GaAs surface in the energy range of 0 to 9 eV. The FWHM of electron energy distribution function was 70 meV. (author).

1994-03-20

43

Mineralogical Data of Shocked Quartz Materials from K/T Boundary and Impact Crater  

Science.gov (United States)

Shocked quartz minerals from the Cretaceous-Tertiary (K/T) boundary and impact craters have been mainly discussed from distribution of optical directions, mean optical refractive index, and X-ray data (1). The purpose of the present study is presentation of the detailed mineralogical data of shocked quartz found in the K/T boundaries and terrestrial impact craters (2,3,4,5). X-ray powder diffraction pattern of shocked quartz aggregate reveals that all Xray peaks are split into major three peaks composed of low-density quartz (LQ), normal quartz (Q), and shocked quartz with high density (SQ). X-ray peaks of (110), (200), (201), (202), and (211) in the hexagonal cell are also split into many peaks. The X-ray intensity among LQ, Q, and SQ phases indicates that the SQ phase shows 36% to 53% in six K/T boundary samples (5). The relative X-ray intensity ratio of ...

1992-07-01

44

Attachment Stimulates Exopolysaccharide Synthesis by a Bacterium  

UK PubMed Central (United Kingdom)

This study examined the hypothesis that solid surfaces may stimulate attached bacteria to produce exopolymers. Addition of sand to shake-flask cultures seemed to induce exopolymer synthesis by a number...Full Text Available

1993-10-01

45

Nonlinear air-coupled emission: The signature to reveal and image microdamage in solid materials  

International Nuclear Information System (INIS)

It is shown that low-frequency elastic vibrations of near-surface planar defects cause high-frequency ultrasonic radiation in surrounding air. The frequency conversion mechanism is concerned with contact nonlinearity of the defect vibrations and provides efficient generation of air-coupled higher-order ultraharmonics, ultrasubharmonics, and combination frequencies. The nonlinear air-coupled ultrasonic emission is applied for location and high-resolution imaging of damage-induced defects in a variety of solid materials.

2007-12-17

46

Process and system for treatment of radioactive waste  

Energy Technology Data Exchange (ETDEWEB)

In a treatment system of radioactive waste solution including sodium sulfate generated from a boiling water type nuclear reactor, waste solution is fed into a thin film evaporator where the waste solution is evaporated and made into powder while precipitating in a peripheral surface of the evaporator vessel. The surface of the precipitated solid is wiped by rotating wiper blades and removed off as radioactive solid powder. The rotational speed of a rotor to which the wiper blades are secured is controlled at a minimum and necessary rotational speed which contributes to make the waste solution into the powder so that the rate of worn out of the wiper blade is decreased.

1985-07-02

47

High Throughput Screening for the Discovery of More Efficient Catalysts for Emissions Control  

Energy Technology Data Exchange (ETDEWEB)

High-throughput synthesis and screening methods have been developed for the discovery of highly active catalysts for the control of emissions from stationary and mobile sources. Low temperature CO oxidation, CO methanation, NOx abatement and the destruction of Volatile Organic Compounds (VOCs) will be discussed. The discovery libraries for primary screening consisted of both 11x11 and 16x16 catalyst arrays on 3 inch and 4 inch quartz wafers, respectively. Catalysts were prepared by robotic liquid dispensing techniques and screened for catalytic activity in Symyx's Scanning Mass Spectrometer. The screening protocols encompassed mixed metal oxides, perovskites and supported base and noble metals. Active hits were further optimized in focus libraries using shallower compositional gradients. The ScanMS is a fast serial screening tool that uses flat wafer catalyst surfaces, local laser heating, a scanning/sniffing nozzle and a quadrupolar ...

2004-03-31

48

Acoustic wave device using plate modes with surface-parallel displacement  

Energy Technology Data Exchange (ETDEWEB)

Solid-state acoustic sensors for monitoring conditions at a surface immersed in a liquid and for monitoring concentrations of species in a liquid and for monitoring electrical properties of a liquid are formed by placing interdigital input and output transducers on a piezoelectric substrate and propagating acoustic plate modes therebetween. The deposition or removal of material on or from, respectively, a thin film in contact with the surface, or changes in the mechanical properties of a thin film in contact with the surface, or changes in the electrical characteristics of the solution, create perturbations in the velocity and attenuation of the acoustic plate modes as a function of these properties or changes in them.

1992-01-01

49

Effect of surface-perturbed intermolecular interaction on adsorption of simple gases on a graphitized carbon surface.  

Science.gov (United States)

In this paper, we investigate the effect of the solid surface on the fluid-fluid intermolecular potential energy. This modified fluid-fluid interaction energy due to the inducement of a solid surface is used in the grand canonical Monte Carlo (GCMC) simulation of various noble gases, nitrogen, and methane on graphitized thermal carbon black. This effect is such that the effective interaction potential energy between two particles close to surface is less than the potential energy if the solid substrate is not present. With this modification the GCMC simulation results agree extremely well with the experimental data over a wide range of pressures while the simulation results with the unmodified potential energy give rise to a shoulder near the neighborhood of monolayer coverage and the significant overprediction of the second and higher layer coverages. In ...

2004-08-31

50

Coal demineralization with Ca(OH)2. Hydrothermal reaction between Ca(OH)2 and quartz; Ca(OH)2 wo mochiita sekitan no kagakuteki dakkai. Ca(OH)2 to sekitan no suinetsu hanno  

Energy Technology Data Exchange (ETDEWEB)

Coal demineralization mechanism and its optimum condition were studied by hydrothermal reaction between Ca(OH)2 and quartz as a coal demineralization model. In experiment, the mixture of powder quartz and Ca(OH)2 water slurry was subjected to reaction in an autoclave under spontaneous pressure at 175-340{degree}C. After dried in N2 gas atmosphere at 105{degree}C, the reaction product was analyzed by X-ray diffraction, thermo-balance and differential thermal analysis. In measurement of quartz conversion, the specimen was analyzed by X-ray diffraction after removal of bound water by heat treatment at 850{degree}C. The mixture of clean coal deashed by NaOH and a fixed amount of quartz was also used as specimen for experiment. As the experimental result, dicalcium silicate hydrate was mainly produced at 175{degree}C, and the product changed into xonotlite through tobermorite by longer treatment at higher ...

1996-10-28

51

Emission and excitation spectra of feldspar inclusions within quartz  

Energy Technology Data Exchange (ETDEWEB)

Emission spectra obtained for three irradiated granular quartz samples under 1.43 eV excitation exhibited the 2.2 and 3.1 eV emission bands characteristic of feldspars. Excitation spectra of these same samples and several others show the 1.44 eV resonance typical of feldspars. This provides convincing evidence that the 2.2 and 3.1 eV infrared stimulated luminescence observed in these granular quartz samples arises from feldspar inclusions.

2004-02-01

52

Time-dependent wavepacket calculations of molecular scattering from surfaces  

International Nuclear Information System (INIS)

An outline is given of time-dependent wavepacket methods as applied to calculations of molecular collisions with solid surfaces. The methods reviewed include numerical integration algorithms for the time-dependent Schroedinger equation, semiclassical wavepacket treatments, and approximations that treat some of the degrees-of-freedom quantum-mechanically and others classically. The computational and numerical characteristics of these methods are discussed, with emphasis on their particular advantages and relevance in the context of certain molecule/surface scattering problems. For the semiclassical and mixed quantal-classical treatments, the approximation errors and their physical origins are discussed. For the quantum wavepacket techniques a numerical error analysis is presented. The computational efficiency of the various algorithms is considered and examined in the context of several applications. The main focus is on ...

1986-01-01

53

Lung cancer in rats exposed to fibrogenic dusts  

Energy Technology Data Exchange (ETDEWEB)

Fischer-344 rats were exposed to quartz dusts and to quartz-bearing oil shale dusts in long-term inhalation studies. Aerosol concentrations of 12 mg/m/sup 3/ and 152-176 mg/m/sup 3/ for quartz and shale dusts, respectively, were used in exposure regimens lasting up to two years. Pulmonary fibrosis was observed in most animals surviving beyond 400 days. Adenocarcinomas and epidermoid carcinomas of the lung were observed in animals from all exposure groups, including those exposed to quartz alone. The pulmonary tumors were a late effect, with the earliest lung tumor being observed after 651 days. 13 references, 10 figures, 4 tables.

1984-01-01

54

Surface modification of magnesium base alloys by gas/plasma nitridation  

Energy Technology Data Exchange (ETDEWEB)

Gas and plasma nitriding processes were executed in the magnesium with modification by titanium in search for an effective surface treatment method for magnesium alloys. Magnesium-nitrogen system has completely no solid solution or solubility, so that nitride should be only formed by eutectic reaction in the liquid phase. Hence, magnesium is difficult or nearly impossible to have its surface modified by nitriding. Addition of nitride forming element into magnesium enables us to lower the onset temperature of nitriding. Magnesium-titanium alloys with 1 to 5 wt% are yielded by the bulk mechanical alloying and, subjected to gas nitriding for various process conditions. Successful co-formation of Mg{sub 3}N{sub 2} as well as TiN becomes a proof to demonstrate the possibility of gas/plasma nitriding in the solid-state magnesium with aid of nitride former. (orig.)

2000-07-01

55

Assembly of Linear Nano-Chains from Iron Oxide Nanospheres with Asymmetric Surface Chemistry  

Science.gov (United States)

Besides the multifunctionality, another equally important aspect of nanoparticles is their engineerability to control the geometrical and chemical properties during fabrication. In this work, we exploited this aspect to define asymmetric surface chemistry of an iron oxide nanosphere by controlling the topology of ligand expression on its surface resulting in a particle with two faces, one displaying only amines and the other only thiols. Specifically, amine-functionalized iron oxide nanospheres were attached on a solid support via a crosslinker containing a disulfide bridge. Liberation of the nanosphere using thiolytic cleavage created thiols on the portion of the particle's surface that interacted with the solid support. Employing a solid-phase strategy and a step-by-step addition of particles, the two unique faces on the same nanosphere served as fittings to ...

2011-01-06

56

Tests on decisive proof for the incinerating and melting facility using the in-can type high frequency induction heating  

Energy Technology Data Exchange (ETDEWEB)

LEDF(Large Equipment Dismantling Facility) is the solid waste processing technology development facility that carries out high-volume reduction and low dosage processing. The high-volume reduction processing of the high dose {alpha}-waste configured with combustible waste, pvc and rubber, spent ion exchange resin, and noncombustible waste have been planned the incinerating and melting facility using the in-can type high frequency induction heating in LEDF. This test is intended to clarify the design data. It was confirmed that the incinerating and melting performance, molten solid properties and exhaust gas processing performance with pilot testing equipment and bench scale equipment. The result of this test are as follows. 1. Processing speed is 6.7 kg/h for the combustible waste, 13.0 kg/h for the ion exchange resin, and 30.0 kg/h for the noncombustible waste. For above optimum processing conditions are as follows. Operating temperature is ...

1999-12-01

57

Characterisation of thin films by phase modulated spectroscopic ellipsometry  

International Nuclear Information System (INIS)

A wide variety of thin film coatings, deposited by different techniques and with potential applications in various important areas, have been characterised by the Phase Modulated Spectroscopic Ellipsometer, installed recently in the Spectroscopy Division, B.A.R.C. The Phase Modulated technique provides a faster and more accurate data acquisition process than the conventional ellipsometry. The measured Ellipsometry spectra are fitted with theoretical spectra generated assuming an appropriate model regarding the sample. The fittings have been done objectively by minimising the squared difference (#chi#"2) between the measured and calculated values of the ellipsometric parameters and thus accurate information have been derived regarding the thickness and optical constants (viz, the refractive index and extinction coefficient) of the different layers, the surface roughness and the inhomogeneities present in the layers. Measurements have been done on (i) ion-implanted ...

2009-12-01

58

Glow Discharge Plasma Nitriding of AISI 304 Stainless Steel  

International Nuclear Information System (INIS)

Glow discharge plasma nitriding of AISI 304 austenitic stainless steel has been carried out for different processing time under optimum discharge conditions established by spectroscopic analysis. The treated samples were analysed by X-ray diffraction (XRD) to explore the changes induced in the crystallographic structure. The XRD pattern confirmed the formation of an expanded austenite phase (#gamma#_N) owing to incorporation of nitrogen as an interstitial solid solution in the iron lattice. A Vickers microhardness tester was used to evaluate the surface hardness as a function of indentation depth (#mu#m). The results showed clear evidence of surface changes with substantial increase in surface hardness.

2007-08-01

59

No. 3 Vol. 42, No. 3, pp. 218-225, 2008 Optimizing performance of makeup products by controlling surface free energy  

British Library Electronic Table of Contents (United Kingdom)

We investigated the use of Surface Free Energy (SFE) measurements, describing coherence between surfaces of two solids, in evaluation of affinity between skin surface and foundation, a possible predictor of makeup longevity. We found that the gp values of skin varied significantly among subjects. After discovering that the SFE values of most available conventional foundation products were very different from that of skin, specially formulated experimental foundations with SFE values close to that of the skin surface were prepared using conventional powder ingredients and novel powder ingredients coated with polyethylene glycol. In our usage tests, the SFE-controlled foundations demonstrated superior performance to that of conventional foundations and most of subjects preferred the SFE-cont...

2009-01-01

60

Reaction of solid sorbents with hydrogen chloride gas at high temperature in a fixed-bed reactor  

Energy Technology Data Exchange (ETDEWEB)

The gas-solid reaction and breakthrough curves in the fixed-bed reactor are of great importance, and being influenced by a number of factors makes the prediction of these factors a difficult problem. In this study, the reaction rate between solid sorbents and hydrogen chloride gas at high temperature was first investigated. On the basis of a fixed-bed reactor, the experimental results were analyzed by the shrinking core model of diffusion and surface chemical reaction control. The results showed that reaction rates of two sorbents with hydrogen chloride gas were controlled by the combination of the surface chemical reaction and diffusion of product layers, and the reaction rates nearly keep constant within 15 h of the initial reaction period and then decrease gradually. The results of the breakthrough curves show that solid sorbents in the fixed-bed reactor are capable of reducing ...

2005-12-01

61

Toward a 2D SPH Multiphysic Code with Solid-Solid & Fluid Interactions for Industrial Related Problems  

CERN Document Server

In the present study, applications of the SPH method to industrial related issues are considered by starting from an existing open source 2D SPH code, namely the SPHYSICS code, which offers an effective ground for numerical developments, which are performed in order to bring an answer to industrial problems, such as simulations of solid/fluid coupling in a free surface flow context. The purpose of the present paper is therefore to expose the numerical developments which yield an enhanced version (referred to as "SPHYSIC2") of the initial code. Firstly, the different features added to obtain the operational code needed for engineering applications are described, and so are the problems raised on this way, offering a kind of review of SPH methods for engineers. Secondly, the validation of the proposed code is partially presented with two well known but difficult test cases, namely the classical "dam break" and "wedge entry" problems. Thirdly, ...

2010-01-01

62

Heterogeneous radiolysis of HCN adsorbed on a solid surface  

International Nuclear Information System (INIS)

Hydrogen cyanide is a key molecule for chemical evolution studies because, when it is exposed to different sources of energy, it forms various compounds of biological importance. To understand the role of minerals in chemical evolution, a series of experiments was performed. First, the adsorption capacity of HCN on different surface minerals was studied; the results show that HCN is readily adsorbed onto the solids proposed (zeolite, serpentine, dolomite, and sodium montmorillonite), in particular zeolite and montmorillonite. Second, the radiolysis of HCN adsorbed on olivine (as an example of a mineral surface) was also followed; it was found that the rate of HCN decomposition by gamma irradiation is enhanced in the presence of the solid. The third series of studies show that organic material was produced in high abundance from HCN at high radiation doses. The radiolytic products included gases (CO_2, ...

2010-07-01

63

Study on possible fuel layering sequence for FIREX target  

International Nuclear Information System (INIS)

A new procedure of fuel layering for the Fast Ignition Realization Experiment (FIREX) target is proposed. A conical laser guide heating technique was experimentally demonstrated in principle as the followings. It employed the target consisting of a polystyrene (PS) shell, a fill tube and a conical laser guide. At first, liquid fuel was fed into the shell and existed around the conical laser guide because the surface tension of the fuel must cause it. Then, it was solidified. The laser light provided a heat source to the conical laser guide so that the solid fuel was moved to the other interior of the shell. This process resulted in missing solid fuel around the conical laser guide. To fill the vacant space, liquid fuel was added as temperature was raised to the melting point. After the liquid fuel addition, temperature was lowered to the solidification point again. During this process, most of the solid ...

2010-08-01

64

Blow forming of recycled 5083 Al alloy and AZ31Mg alloy by solid state recycling  

Energy Technology Data Exchange (ETDEWEB)

Blow forming characteristics of 5083 Al alloy and AZ31 Mg alloy recycled by solid state recycling were investigated. Scraps with different volume were recycled by hot extrusion and hot rolling in air. Oxide layers, which were contaminants from scrap surface, were distributed parallel to the extrusion direction in the recycled specimens. In the blow-forming test, the specimen from smaller scraps exhibited lower formability. The oxygen concentration in the recycled specimens was approximately proportional to the total surface area of scraps in the recycled specimen per unit volume. The low formability of the recycled specimens is likely to be attributed to contamination level of oxide. (orig.)

2005-07-01

65

Quantum simulation of molecular interaction and dynamics at surfaces  

British Library Electronic Table of Contents (United Kingdom)

The interaction between molecules and solid surfaces plays important roles in various applications, including catalysis, sensors, nanoelectronics, and solar cells. Surprisingly, a full understanding of molecule-surface interaction at the quantum mechanical level has not been achieved even for very simple molecules, such as water. In this mini-review, we report recent progresses and current status of studies on interaction between representative molecules and surfaces. Taking water/metal, DNA bases/carbon nanotube, and organic dye molecule/oxide as examples, we focus on the understanding on the microstructure, electronic property, and electron-ion dynamics involved in these systems obtained from first-principles quantum mechanical calculations. We find that a quantum mechanical description ...

2011-01-01

66

Crawling beneath the free surface: Water snail locomotion  

CERN Document Server

Land snails move via adhesive locomotion. Through muscular contraction and expansion of their foot, they transmit waves of shear stress through a thin layer of mucus onto a solid substrate. Since a free surface cannot support shear stress, adhesive locomotion is not a viable propulsion mechanism for water snails that travel inverted beneath the free surface. Nevertheless, the motion of the freshwater snail, Sorbeoconcha physidae, is reminiscent of that of its terrestrial counterparts, being generated by the undulation of the snail foot that is separated from the free surface by a thin layer of mucus. Here, a lubrication model is used to describe the mucus flow in the limit of small amplitude interfacial deformations. By assuming the shape of the snail foot to be a traveling sine wave and the mucus to be Newtonian, an evolution equation for the interface shape is obtained and the resulting propulsive ...

2008-01-01

67

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

Energy Technology Data Exchange (ETDEWEB)

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

1991-05-25

68

Integrated numerical modeling of surface-subsurface-coupled, 2-phase fluid/heat flow in limnological system 1. New type of modeling and experimental study; Shizen suirikei no ryutai{center_dot}netsu ido togo moderingu no kokoromi 1. Ryutai{center_dot}netsu ido no atarashii teishikika to jikkenteki kento  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the comprehensive modeling method of fluid and heat flows in the hydrological system. Based upon the concept that the hydrological system is composed of the air-water 2-phase fluids, and the rock phase, various natural processes are modeled including surface/subsurface 2-phase mass transfer, heat exchanges between fluid phases, between fluid and solid phases, and sensible/latent heat exchanges on the ground surface. A field-oriented numerical simulator is developed, in which a set of governing equations is solved for different variables on the surface and in subsurface regions, respectively. Results of an experimental study are presented, in which transient formulation of heat exchange between fluid/solid phases is examined through matching of the observation and calculated performances. (author)

1999-08-31

69

Integrated numerical modeling of surface-subsurface-coupled, 2-phase fluid/heat flow in limnological system 1. New type of modeling and experimental study. Shizen suirikei no ryutai[center dot]netsu ido togo moderingu no kokoromi 1. Ryutai[center dot]netsu ido no atarashii teishikika to jikkenteki kento  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the comprehensive modeling method of fluid and heat flows in the hydrological system. Based upon the concept that the hydrological system is composed of the air-water 2-phase fluids, and the rock phase, various natural processes are modeled including surface/subsurface 2-phase mass transfer, heat exchanges between fluid phases, between fluid and solid phases, and sensible/latent heat exchanges on the ground surface. A field-oriented numerical simulator is developed, in which a set of governing equations is solved for different variables on the surface and in subsurface regions, respectively. Results of an experimental study are presented, in which transient formulation of heat exchange between fluid/solid phases is examined through matching of the observation and calculated performances. (author)

1999-08-31

70

Radiative properties of a solar cavity receiver/reactor with quartz window  

British Library Electronic Table of Contents (United Kingdom)

An energy transfer and conversion model for high-temperature solar cavity receivers has been developed using the transport behaviour of solar radiation as described by the spectral radiative exchange factors. A Monte-Carlo ray-tracing method coupled with optical properties was adopted, to predict radiation characteristics of the solar collector system by calculating radiative exchange factors. A cavity receiver with a plano-convexo quartz window was proposed, based upon the directional characteristics of the focal flux and the redistribution effect of the quartz window. Parametric studies on the windowed receiver provided a more uniform flux distribution, higher efficiency and lower loss than the windowless receivers. The predicted results serve as a design reference for the solar receiver...

2011-01-01

71

Thermodynamic and kinetic aspects of surface acidity  

Science.gov (United States)

Our research in the general area of acid catalysis involves the characterization of solid acidity and the corresponding assessment of catalytic performance of acidic materials. Acid characterization studies are required to provide essential information about the type of acid site (i.e., Lewis versus Bronsted), the strength of the sites, and the mobility of molecules adsorbed on the acid sites. An accurate measure of acid strength is given by the heat of adsorption of a basic probe molecule on the acid site. A thermodynamic representation of the mobility of adsorbed species on these sites is given by the entropy of adsorption. Important techniques used in these acid site characterization studies include microcalorimetry, thermogravimetric measurements, temperature programmed desorption, infrared spectroscopy and solid state nuclear magnetic resonance. The combination of these acid site characterization studies with reaction kinetics measurements ...

1992-01-01

72

Solidification of radioactive waste effluents  

Energy Technology Data Exchange (ETDEWEB)

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

1983-10-11

73

X-ray diffraction studies of palladium silicide thin films  

Energy Technology Data Exchange (ETDEWEB)

The solid state reaction between a Pd thin film and a Si substrate produces a single new phase, Pd/sub 2/Si, for temperatures <700/sup 0/C. When the substrate is a single crystal of (111) surface orientation, this process is particularly interesting because the silicide grows epitaxially. Growth of epitaxial interfacial Pd/sub 2/Si was the focus of this study using X-ray diffraction techniques.

1985-01-01

74

Radon concentration measurements in the soil  

International Nuclear Information System (INIS)

Radon concentration measurement in the ground can be used for the prospecting for uranium and earthquake prediction. Some results of radon concentration measurement in the soil are presented here. The moisture condensation at the detector surface can affect on the detection efficiency. Due to this problem we tested a few filter papers on water permeability. The ratio of track densities on solid state nuclear track detector (SSNTD) in the open and the closed diffusion chamber is also determined. (author)

75

Microwaves action applied to chemical reactions and processes; L`azione delle microonde nelle reazioni e nei processi chimici  

Energy Technology Data Exchange (ETDEWEB)

Microwaves improve the rate of many chemical reactions either interacting with the solvent, when the reaction is carried out in solution, or with the surface of a solid substrate where a suitable reagent is dispersed (dry chemistry). A few examples of chemical reactions positively affected by microwaves are described: particularly interesting are those concerning polymers and radio-pharmaceuticals.

1997-03-01

76

Localized Rayleigh Instability in Evaporation Fronts  

CERN Document Server

A qualitatively different manifestation of the Rayleigh instability is demonstrated, where, instead of the usual extended undulations and breakup of the liquid into many droplets, the instability is localized, leading to an isolated narrowing of the liquid filament. The localized instability, caused by a nonuniform curvature of the liquid domain, plays a key role in the evaporation of thin liquid films off solid surfaces.

2009-01-01

77

Isotopic effects on solubility-limited mass transfer  

Energy Technology Data Exchange (ETDEWEB)

In our previous theoretical analyses, solubility-limited mass transfer from waste solids applies if a species is at a constant elemental concentration in liquid at the waste surface. For an element with isotopes that decay appreciably during the time of interest, a solubility boundary condition results in a time-dependent boundary concentration of each isotope. Here we present mass-transfer equations that include the effects of isotopic decay boundary conditions. 9 refs., 1 fig.

1989-06-01

78

Catalytic chemistry  

Energy Technology Data Exchange (ETDEWEB)

Most chemical reactions in industry and biology are catalytic and play a role at some stage of the processing of about 80% of the goods manufactured in the U.S., yet catalysis is a neglected subject in chemical education. This book integrates the fragmentary treatment accorded the topic until now. It covers, in a unified way, catalysis in solutions, by enzymes, in synthetic polymers within the molecular scale cages of zeolites and other molecular sieves, and on surfaces of inorganic solids. The central ideas are chemical; and principles are illustrated by emphasizing industrial reactions and catalysts.

1991-01-01

79

Acoustic wave propagation in fluid metamaterial with solid inclusions  

CERN Document Server

Acoustic waves propagation of in composite of water with embedded double-layered silicone resin/silver rods is considered. Approximate values of effective dynamical constitutive parameters are obtained. Frequency ranges of simultaneous negative constitutive parameters are found. Localized surface states on the interface between metamaterial and ``normal'' material are found. Doppler effect in metamaterial is considered. Presence of anomalous modes is shown.

2010-01-01

80

A solution for solid state detector and preamplifier protection, during HV application and removal transition periods  

International Nuclear Information System (INIS)

Surface barrier detectors may be damaged, because of microplasma breakdown, in rapid application of bias voltage. The high performance FETs of very low noise preamplifiers may also be damaged by rapid changes of the bias voltage. The electronic device described permits the gradual application and removal of the bias voltage, without any influence on the power supply specification. (Auth.).

81

2D cavity grid quantum computing  

Energy Technology Data Exchange (ETDEWEB)

We propose a novel scheme for scalable solid state quantum computing, where superconducting microwave transmission line resonators (cavities) are arranged in a two-dimensional grid on the surface of a chip, coupling to superconducting qubits (charge or flux) at the intersections. We analyze how tasks of quantum information processing can be implemented in such a topology, including efficient two-qubit gates between any two qubits on the grid and elements of fault-tolerant computation.

2008-07-01

82

A combinatorial library of micro-topographies and chemical compositions for tailored surface wettability  

Energy Technology Data Exchange (ETDEWEB)

Surface modification of topography and chemistry in order to achieve a specific water contact angle (CA) has been explored by using a novel combinatorial screening platform. The screening arrays consisted of 507 distinct combinations of micro-topographies and chemical compositions. By performing chemical modifications with 1H, 1H, 2H, 2H perfluoroethyltriethoxy-silane (PFS) and n-octadecyltriethoxysilane (ODS) on standard silicon wafers it was possible to include both superhydrophobic and very hydrophilic pad arrays in the same screening platform. Surfaces modified with PFS were more hydrophobic than surfaces modified with ODS, while the unmodified silicon surfaces were hydrophilic. For the PFS modified surfaces the largest CAs were achieved with a small pillar size of X = 1 {mu}m and an intermediate inter-pillar gap size of Y = 4 {mu}m with superhydrophobic CAs over 170 . ...

2011-06-15

83

Study of the action of a phosphonate additive on steel scale deposit and corrosion in the hydrodynamic conditions of a channel flow cell; Etude de l'action d'un additif phosphone sur l'entartrage et sur la corrosion de l'acier dans les conditions hydrodynamiques d'une cellule a canal  

Energy Technology Data Exchange (ETDEWEB)

In cooling systems, an improved control of scale deposit and corrosion processes is a major challenge and an realistic evaluation tool for water treatments is of the utmost economic importance. In this study, a channel flow cell was used to allow in-situ electrochemical measurements in well defined electrolyte tube flowing conditions. An expression of the mass transfer towards the electrode was established where the diffusion-limited current is a function of Re{sup 1/3} in the laminar regime and was verified experimentally using the redox couples Fe[CN]{sub 6}{sup 4-}/ Fe[CN]{sub 6}{sup 3-} and O{sub 2}/OH{sup -}. This hydrodynamically controlled experimental device was developed to investigate scale deposit processes and to evaluate scale inhibitor efficiency using a electrochemical quartz crystal microbalance. Experiments were performed on three different waters, at various flow rates and temperatures. The efficiency of a well known phosphonate (HEDP) was tested ...

2000-10-17

84

Process for the production of a particularly finely divided, homogeneous transition metal phosphide and transition metal chalcogenide. Verfahren zum Herstellen besonders feinteiliger, homogener Uebergangsmetallphosphide und Uebergangsmetallchalkogenide  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the invention is a process for the production of a particularly finely divided, homogeneous transition metal phosphide and transition metal chalcogenide of Daltonian stochiometry by the conversion of at least one powder transition metal or a transition metal alloy with phosphorus or with a chalcogen at raised temperature, which is characterized by the fact that the conversion is carried out in the presence of at least one inert finely divided auxiliary material which is soluble in water and does not sinter together at the reaction temperature, and that the conversion produce removes the auxiliary material. Even relatively small quantities of the auxiliary material are sufficient to ensure rapid and homogeneous conversion of the reaction partners to the reaction product having a large surface. A ratio of 1 part by volume of a mixture of a transition metal and phosphorus or chalcogen to 1 part by volume of finely divided auxiliary material proved ...

1980-06-26

85

Physical, biochemical and physiological effects of ultraviolet radiation on Brassica napus and Phaseolus vulgaris  

International Nuclear Information System (INIS)

In order to follow some of the changes induced by ultraviolet-B (UV-B, 280-320 nm) radiation in Phaseolus vulgaris and Brassica napus, experiments were designed to localize sites of changes in leaves and to correlate some of the physiological and biochemical changes with penetration of UV-B radiation. B.napus was exposed to 8.9 kJ m"-"2 day"-"1 biologically effective UV-B radiation (UV-B_B_E). The penetration of UV-B radiation into the leaf was followed using a quartz fibre optic microprobe. Monochromatic radiation at 310 nm was decreased by ca 50 and 34% in the adaxial and abaxial epidermis, respectively, in plants not exposed to UV-B, whereas the radiation was decreased by ca 70 and 42%, respectively, in the same region in UV-treated plants. Polychromatic radiation showed a wavelength dependent change mainly for the collimated radiation. The results correlated with the distribution of phenolic compounds analysed from 40 #mu#m paradermal leaf sections. The first ...

1991-11-05

86

Enhancement of Au nanoparticles formed by in situ electrodeposition on direct electrochemistry of myoglobin loaded into layer-by-layer films of chitosan and silica nanoparticles.  

Science.gov (United States)

In the present work, a new kind of myoglobin (Mb)/Au nanoparticles composite film was fabricated on pyrolytic graphite (PG) electrodes. Oppositely charged chitosan (CS) and silica (SiO(2)) nanoparticles were alternately adsorbed on the PG surface by the electrostatic interaction between them, forming {CS/SiO(2)}(5) layer-by-layer films. Mb and HAuCl(4) in solution were then simultaneously loaded into {CS/SiO(2)}(5) films. The loaded Au(III) in the films were electrochemically reduced into Au nanoparticles, forming nanocomposite films, designated as {CS/SiO(2)}(5)-Mb-Au. Various techniques such as cyclic voltammetry (CV), square wave voltammetry (SWV), quartz crystal microbalance (QCM), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) analysis were used to characterize the films. Compared with {CS/SiO(2)}(5)-Mb films without Au nanoparticles inside, the {CS/SiO(2)}(5)-Mb-Au films ...

2008-12-01

87

Spray forming: A numerical investigation of the influence of the gas to melt ratio on the billet surface temperature  

Energy Technology Data Exchange (ETDEWEB)

The relationship between the gas to melt ratio (GMR) and the surface temperature of an evolving billet surface in spray forming is investigated numerically. The basis for the analysis is an integrated approach for modelling the entire spray forming process. This model includes the droplet atomization taking thermal coupling into consideration and the deposition of material at the surface of the billet taking geometrical aspects such as shading into account. The coupling between these two models is accomplished by ensuring that the total droplet size distribution of the spray is the summation of ''local'' droplet size distributions along the r-axis of the spray cone. The criterion for a successful process has been a predefined process window characterised by a desired fraction solid range at a certain distance from the atomizer. Inside this process window, the gas and ...

2005-06-01

88

Infrared stimulated luminescence in quartz  

Energy Technology Data Exchange (ETDEWEB)

Infrared (IR, 880 nm) stimulated luminescence (IRSL) signal was observed from quartz at room temperature. The characteristics of the signal such as its response to {gamma}-ray irradiation, thermal stability and thermal assistance energy show that the signal originates from different traps than those responsible for the luminescence signal stimulated by green light (GL, 514 nm). The IRSL signal's short lifetime (18 days at 15 deg. C) may have been the reason why it was not detected in previous experiments. The decay of the IR signal after GL illumination was observed. The thermoluminescence at 76 deg. C was enhanced after IR illumination.

2005-02-01

89

EFFECTS OF QUARTZ PARTICLE SIZE AND SUCROSE ADDITION ON MELTING BEHAVIOR OF A MELTER FEED FOR HIGH-LEVEL GLASS  

Energy Technology Data Exchange (ETDEWEB)

The behavior of melter feed (a mixture of nuclear waste and glass-forming additives) during waste-glass processing has a significant impact on the rate of the vitrification process. We studied the effects of silica particle size and sucrose addition on the volumetric expansion (foaming) of a high-alumina feed and the rate of dissolution of silica particles in feed samples heated at 5 C/min up to 1200 C. The initial size of quartz particles in feed ranged from 5 to 195 {micro}m. The fraction of the sucrose added ranged from 0 to 0.20 g per g glass. Extensive foaming occurred only in feeds with 5-{micro}m quartz particles; particles {ge}150 {micro}m formed clusters. Particles of 5 {micro}m completely dissolved by 900 C whereas particles {ge}150 {micro}m did not fully dissolve even when the temperature reached 1200 C. Sucrose addition had virtually zero impact on both foaming and the dissolution of silica particles. Over 100 sites in the United ...

2010-07-28

90

Wind tunnel and numerical study of a small vertical axis wind turbine  

British Library Electronic Table of Contents (United Kingdom)

This paper presents a combined experimental and computational study into the aerodynamics and performance of a small scale vertical axis wind turbine (VAWT). Wind tunnel tests were carried out to ascertain overall performance of the turbine and two- and three-dimensional unsteady computational fluid dynamics (CFD) models were generated to help understand the aerodynamics of this performance. Wind tunnel performance results are presented for cases of different wind velocity, tip-speed ratio and solidity as well as rotor blade surface finish. It is shown experimentally that the surface roughness on the turbine rotor blades has a significant effect on performance. Below a critical wind speed (Reynolds number of 30,000) the performance of the turbine is degraded by a smooth rotor surface finis...

2010-01-01

91

Silica Polyamine Composites: New Supramolecular Materials for Cation and Anion Recovery and Remediation  

British Library Electronic Table of Contents (United Kingdom)

Summary: The surface coverage of amorphous silica gels used in the synthesis of silica polyamine composites has been investigated by 29Si NMR. By diluting the polyamine anchor silane, chloropropyl trichlorosilane, with methyl trichlorosilane it was found that surface coverage could be markedly improved for a range of amine polymers after grafting to the silica surface. The commensurate decrease in the number of anchor points and increase in the number of free amines results in an increase in metal capacity and/or an improvement in capture kinetics. Solid state CPMAS-13C NMR has been employed to investigate the structure and metal ion binding of a series of these composite materials. It is reported that the highly branched polymer, poly(ethyleneimine) (PEI) exhibits much broader 13C NMR res...

2006-01-01

92

LES of turbulent surface shear stress and pressure-gradient-driven flow on shallow continental shelves  

British Library Electronic Table of Contents (United Kingdom)

Turbulent shear flows on shallow continental shelves (here shallow means that the interaction with the solid, no-slip bottom is important) are of great importance because tide- and wind-driven flows on the shelf are drivers of the transfer of momentum, heat, and mass (gas) across the air?sea interface. These turbulent flows play an important role because vertical mixing and current are vectors for the transport of sediment and bioactive material on continental shelves. Understanding the dynamics of this class of flows presents complications because of the presence of a free surface and also because the flow can be driven by a pressure gradient (a tidal current), a stress at the free surface (a wind-driven current), or a combination of both. In addition, the flow can be modified by the pres...

2011-01-01

93

Interfacial ultrafine-grained structures on aluminum alloy 6061 joint and copper alloy 110 joint fabricated by magnetic pulse welding  

British Library Electronic Table of Contents (United Kingdom)

Magnetic pulse welding is a solid state impact welding process, similar to explosive welding, which produces metallurgical bond by oblique high-speed impact between two metal bodies. This violent impact removes the metal surface oxide layers and then joins the two atomic level clean metal surfaces together by the incidental compression pressure. The impact velocity is at 200?400?m/s and the being welded metal surface undergoes severe plastic deformation with strain rate in the order of 106?107?s?1. The ultrafine-grained structure was observed on the welded interface. This article studied two types of similar material lap joint interfaces and the base metals were aluminum alloy 6061 and copper alloy 110. Nano-indentation testing shows that the welded interfaces have significantly greater ha...

2010-01-01

94

Granular flow considerations in the design of a cascade solid breeder reaction chamber  

International Nuclear Information System (INIS)

Both horizontally and vertically oriented rotating chambers with granular material held on the inner surface by centrifugal action are examined. Modifications to the condition for controlled quasi-static flow on an incline plane, phi/sub w/ < #alpha# < phi/sub r/, where phi/sub w/ is the wall friction angle, #alpha# is the angle of inclination of the plane, and phi/sub r/ is the drained angle of repose of the material are examined for the case of horizontal and vertical surfaces of revolution. Allowed included half angles for horizontally oriented chambers are likely to be in the range of 30"0 +- 10"0 for ceramic particles and metal surfaces. For vertical orientations the maximum half-angle of the top cone is slightly less than the wall friction angle phi/sub w/ while the lower portion can have a half angle as large as (90"0 - phi/sub w). Percolation of fines through shearing granular solids is ...

1970-05-01

95

Solid/liquid lubrication of ceramics at elevated temperatures  

Energy Technology Data Exchange (ETDEWEB)

This study investigates the effect of solid and liquid lubrication on friction and wear performance of silicon nitride (Si{sub 3}N{sub 4}) and cast iron. The solid lubricant was a thin silver film ({approx}2 {mu}m thick) produced on Si{sub 3}N{sub 4} by ion-beam-assisted deposition. A high-temperature polyol-ester-base synthetic oil served as the liquid lubricant. Friction and wear tests were performed with pin-on-disk and oscillating-slider wear test machines at temperatures up to 300{degrees}C. Without the silver films, the friction coefficients of Si{sub 3}N{sub 4}/Si{sub 3}N{sub 4} test pairs were 0.05 to 0.14, and the average wear rates of Si{sub 3}N{sub 4} pins were {approx}5 x 10{sup -8} mm{sup 3} N{sup -1}. The friction coefficients of Si{sub 3}N{sub 4}/cast iron test pairs ranged from 0.08 to 0.11, depending on test temperature. The average specific wear rates of cast iron pins were {approx}3 x 10{sup -7} mm{sup 3} N{sup -1} m{sup -1}. ...

1996-04-01

96

Secondary ions from condensed gas solids by singly and multiply charged ion impacts  

International Nuclear Information System (INIS)

Ion desorption from a condensed gas solid Ne impacted by singly- and multiply-charged Ar"q"+ ions (q = 1-7) has been investigated. Various secondary ions such as cluster ions, Ne"+_n (n = 2-20) as well as atomic ions are observed. Mass spectral patterns, thickness dependence of the yields, and kinetic energy distributions of the desorbed Ne"+_n (n = 1,2) depend strongly on the projectile charge state. These results indicate that the dissipation of the projectile potential energy on the surface leads to the desorption of the monomer and small cluster ions by a Coulomb repulsion between adjacent target ions.

2009-11-01

97

Heteropolyanion-based ionic hybrid solid: A green bulk-type catalyst for hydroxylation of benzene with hydrogen peroxide  

British Library Electronic Table of Contents (United Kingdom)

A novel heteropolyanion-based ionic hybrid was prepared by combining the divalent ionic liquid (IL) cation of 1,1'-(butane-1,4-diyl)-bis(3-methylimidazolium) with the Keggin-structured V-containing heteropolyanion, and characterized by ^1H NMR, FT-IR, ESI-MS, XRD, SEM, TG, BET surface area, melting point, and elemental analysis. Its catalytic activity was evaluated in the hydroxylation of benzene with aqueous H2O2, including the testing of the influence of organic cations, catalytic reusability and optimization of reaction conditions. This hybrid is characterized to be semi-amorphous nanoparticles with a IL-like composition. The hybrid catalyst leads to the liquid-solid biphasic reaction system for hydroxylation of benzene with H2O2, presenting such advantages as high catalytic activity, c...

2011-01-01

98

Evaluation of CO2 adsorption capacity of solid sorbents  

British Library Electronic Table of Contents (United Kingdom)

The CO2 adsorption capacity of the low-cost solid sorbents of waste tire char (TC) and chicken waste char (CW) was compared with commercial active carbon (AC) and 5?? zeolite (ZA) using thermogravimetric analysis (TG), pressurized TG, and differential scanning calorimetry (DSC). The sorbents were degassed in a TG up to 150??C to release all gases on the surface of the sample, then cooled down to the designed temperature for adsorption. TG results indicated that the CO2 adsorption capacity of TC was higher than that of CW, but lower than those of AC and ZA. The maximum adsorption rate of TC at 50??C was 0.61% min?1, lower than that of AC, but higher than that of CW, 0.44% min?1. The maximum adsorption rate of ZA at 50??C was 3.1% min?1. When the pressure was over 4?bar, the adsorption rate ...

2011-01-01

99

Equilibrium headspace analysis of volatile flavor compounds extracted from soursop (Annona muricata) using solid-phase microextraction  

British Library Electronic Table of Contents (United Kingdom)

The influence of headspace solid-phase microextraction (HS-SPME) variables, namely, sample concentration, salt concentration and sample amount, on the equilibrium headspace analysis of the main volatile flavor compounds released from soursop was investigated. A total of 35 volatile compounds, comprising 19 esters, six alcohols, three terpenes, two acids, two aromatics, two ketones and an aldehyde, were identified. The results indicated that all response-surface models were significantly (p<0.05) fitted for 10 target volatile flavor compounds. The results further indicated that more than 65% of the variation in the equilibrium headspace concentrations of target volatile flavor compounds could be explained by the final reduced models, with high R2 values ranging from 0.658 to 0.944. Multiple...

2010-01-01

100

A novel graphene nanosheets coated stainless steel fiber for microwave assisted headspace solid phase microextraction of organochlorine pesticides in aqueous samples followed by gas chromatography with electron capture detection  

British Library Electronic Table of Contents (United Kingdom)

In this study, a novel graphene nanosheets (GNSs) coated solid phase microextraction (SPME) fiber was prepared by immobilizing microwave synthesized GNSs on a stainless steel wire. Microwave synthesized GNSs were verified by X-ray diffraction, field emission-scanning electron microscopy (FE-SEM) and transmission electron microscope (TEM). GNS-SPME fiber was characterized using FE-SEM and the results showed the GNS coating was homogeneous, porous, and highly adherent to the surface of the stainless steel fiber. The performance and feasibility of the GNS-SPME fiber was evaluated under one-step microwave assisted (MA) headspace (HS) SPME followed by gas chromatography with electron capture detection for five organochlorine pesticides (OCPs) in aqueous samples. Parameters influencing the extra...

2011-01-01

101

Uncertainties of retrospective radon concentration measurements by multilayer surface trap detector  

Energy Technology Data Exchange (ETDEWEB)

The detector for retrospective radon exposure measurements is developed. The detector consists of the multilayer package of solid-state nuclear track detectors LR-115 type. Nitrocellulose films works both as {alpha}-particle detector and as absorber decreasing the energy of {alpha}-particles. The uncertainties of implanted {sup 210}Pb measurements by two- and three-layer detectors are assessed in dependence on surface {sup 210}Po activity and gross background activity of the glass. The generalized compartment behavior model of radon decay products in the room atmosphere was developed and verified. It is shown that the most influencing parameters on the value of conversion coefficient from {sup 210}Po surface activity to average radon concentration are aerosol particles concentration, deposition velocity of unattached {sup 218}Po and air exchange rate. It is demonstrated that with the use of additional information on ...

2006-07-01

102

Numerical investigation of boiling regime transition mechanism by a Lattice-Boltzmann model  

Energy Technology Data Exchange (ETDEWEB)

A numerical study has been performed to investigate the hydrodynamic aspects of the pool boiling on horizontal-, vertical- and downward-facing surfaces. The FlowLab code, which is based on a Lattice-Boltzmann (LB) model of two-phase flows, is employed. Macroscopic properties, such as surface tension ({sigma}) and contact angle ({beta}), are implemented through the fluid-fluid (G{sub {sigma}}) and fluid-solid (G{sub t}) interaction potentials. The model is found to express a linear relation between the macroscopic properties ({sigma}, {beta}) and microscopic parameters (G{sub {sigma}}, G{sub t}). The simulation results on bubble departure diameter appear to have the same parametric dependence as the empirical correlation. Hydrodynamic aspects of two-phase flow regime transition mechanism are investigated for different surface-coolant configurations. Results of the LB simulation clearly demonstrate that ...

2001-02-01

103

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

Energy Technology Data Exchange (ETDEWEB)

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

1991-05-25

104

Upgrading of brown coal by slurry-dewatering; Kattan no yuchu dassui ni yoru clean kotai nenryo no seizo  

Energy Technology Data Exchange (ETDEWEB)

This paper describes an outline of solid fuel production process from brown coal and the investigation results of its elemental techniques. Dried coal is produced by this process which consists of a dewatering of crushed brown coal in oil-based solvent, a solid and liquid separation of slurry, and a remained oil recovery by heating. This process is characterized by the higher thermal efficiency compared with usual drying and the restraint of spontaneous combustion of product coal. It was revealed that solid fuel with low moisture, low ash, low sulfur, and suppressed spontaneous combustion property can be produced from Australian brown coal through this process. From the comparison between kerosene and fuel oil A, it was confirmed that the oil content during dewatering was smaller and the oil recovery by heating was easier by using a solvent with lower boiling point. It was also confirmed that the spontaneous combustion ...

1996-10-28

105

Ionic conductivity enhancement for lithium solid electrolyte; Lithium ion dodensei kotai denkaishitsu no dodensei kojo kiko no kaimei  

Energy Technology Data Exchange (ETDEWEB)

For the development of high ionic conductive solid electrolyte, LiTi2(PO4)3 (LTP), one of the promising inorganic solid electrolyte, was synthesized to investigate an effect of additional lithium salt on the ion conductivity. Lithium salt added LTP composite electrolyte sintered at 900{degree}C exhibited highest conductivity, which was two order magnitude higher than pure LTP. Effects of lithium salt addition are as follows. Conductivity of the composite electrolyte provided larger sintering temperature dependence than the pure LTP. From X-ray diffraction analysis, structures and compositions were resemble between two composite electrolytes. Byproducts except LTP provided rather low conductivity. It was suggested that melted constitution in the composite can affect the sintering improvement by the additional lithium salt at temperatures over 800 {degree}C. From the observation of ruptured surface of sintered specimens, ...

1996-08-01

106

Chip type aluminum solid electronic capacitor using polypyrrole. Polypyrrole wo mochiita chip gata aluminum kotai denkai condenser  

Energy Technology Data Exchange (ETDEWEB)

In the past, organic substance is generally deemed as electrical insulator, but in recent years, molecular crystals and polymers showing electroconductivity like metal were synthesized and even those showing superconductivity have appeared. These materials are called organic metals or synthetic metals and have peculiar solid state physical properties. Examples of real application of organic electroconductive materials are becoming available, but in this article, a chip type aluminum solid electrolytic capacitor using polypyrrole is introduced. There are four kinds of capacitors including ceramic capacitors and aluminum electrolytic capacitors, etc. The aluminum electrolytic capacitor is most retarded than any other type of capacitor in introducing its chip type since its use of electrolytic solution becomes an obstacle. Polypyrrole synthesized by electrolytic polymerization through anode oxidation of pyrrole has good stability and high ...

1990-07-05

107

Characterization of proton exchange membrane materials for fuel cells by solid state nuclear magnetic resonance  

Energy Technology Data Exchange (ETDEWEB)

Solid-state nuclear magnetic resonance (NMR) has been used to explore the nanometer-scale structure of Nafion, the widely used fuel cell membrane, and its composites. We have shown that solid-state NMR can characterize chemical structure and composition, domain size and morphology, internuclear distances, molecular dynamics, etc. The newly-developed water channel model of Nafion has been confirmed, and important characteristic length-scales established. Nafion-based organic and inorganic composites with special properties have also been characterized and their structures elucidated. The morphology of Nafion varies with hydration level, and is reflected in the changes in surface-to-volume (S/V) ratio of the polymer obtained by small-angle X-ray scattering (SAXS). The S/V ratios of different Nafion models have been evaluated numerically. It has been found that only the water channel model gives the measured S/V ratios in the ...

2010-03-15

108

Potential of high-average-power solid state lasers  

Energy Technology Data Exchange (ETDEWEB)

We discuss the possibility of extending solid state laser technology to high average power and of improving the efficiency of such lasers sufficiently to make them reasonable candidates for a number of demanding applications. A variety of new design concepts, materials, and techniques have emerged over the past decade that, collectively, suggest that the traditional technical limitations on power (a few hundred watts or less) and efficiency (less than 1%) can be removed. The core idea is configuring the laser medium in relatively thin, large-area plates, rather than using the traditional low-aspect-ratio rods or blocks. This presents a large surface area for cooling, and assures that deposited heat is relatively close to a cooled surface. It also minimizes the laser volume distorted by edge effects. The feasibility of such configurations is supported by recent developments in materials, fabrication processes, and optical ...

1984-09-25

109

Enhancement of the decontamination factor for liquid radioactive waste and other radioactive materials  

International Nuclear Information System (INIS)

Decommissioning of radiological and nuclear installations is for this century the new challenge. One of the performance criteria is the reduction of total quantities of radioactive materials (liquid or solid) arising from dismantling and decontamination of radiological and nuclear installations. In this work we present a new application of the water soluble polymers used as: - flocculation agents in treatment and conditioning process within the management of radioactive liquid materials; - strippable coatings on solid materials based on the water soluble polymers. The parameters of water soluble polymers made in our Institute by radiation processing have been analysed, namely the molecular average weight, composition, and efficiency of utilization of these polymeric materials as well as the content of ash, additives, decontamination factor, consumption per surfaces/liter, corrosion aspects, compatibility with various ...

2003-10-20

110

Burner for rotary kiln; Braender til roteroven samt fremgangsmaade til dannelse af en braenderflamme med braenderen  

Energy Technology Data Exchange (ETDEWEB)

Burner for feeding a solid and a liquid or gaseous fuel to a kiln comprises a central supply pipe for liquid or gas surrounded concentrically by a first pipe providing an annular passage through which primary air is supplied. Concentrically surrounding that pipe is a second pipe providing an annular channel for supply of solid fuel in carrier air stream. The outlet end of the first concentric pipe is closed by a plate fixed mounted at the pipe end and providing multiple nozzles having their axes parallel to the burner axis. The surface of the plate facing the burning zone provides a divergence opening for the central pipe while the inner surface is formed with helical teeth. These are engaged by complementary teeth mounted on the end of the central pipe which is rotatable and biased by springs so that the teeth are in engagement. Rotation of the pipe causes relative axial motion of the teeth to create ...

1994-10-31

111

A space crystal diffraction telescope for the energy range of nuclear transitions  

Energy Technology Data Exchange (ETDEWEB)

This paper contains literature from American Power Conference Air Toxics Being Measured Accurately, Controlled Effectively NO{sub x} and SO{sub 2} Emissions Reduced; Surface Condensers Improve Heat Rate; Usable Fuel from Municipal Solid Waste; Cofiring Technology Reduces Gas Turbine Emissions; Trainable, Rugged Microsensor Identifies of Gases; High-Tc Superconductors Fabricated; High-Temperature Superconducting Current Leads; Vitrification of Low-Level Radioactive and Mixed Wastes; Characterization, Demolition, and Disposal of Contaminated Structures; On-Line Plant Diagnostics and Management; Sulfide Ceramic Materials for Improved Batteries; Flywheel Provides Efficient Energy Storage; Battery Systems for Electric Vehicles; Polymer-Electrolyte Fuel Cells for Transportation; Solid-Oxide Fuel Cells for Transportation; Surface Acoustic Wave Sensor Monitors Emissions in Real-Time; Advance Alternative-Fueled ...

1995-04-01

112

Studies on the CRUD Deposition on Fuel Cladding Surface Using AOA Water Chemistry Loop  

International Nuclear Information System (INIS)

Axial offset anomaly (AOA) is caused by the deposition of crud on the fuel cladding of a PWR. When significant levels of crud build up on the cladding, boron can accumulate in the pores of the crud as a concentrated solution or solid phase, and cause the flux depression. Numerous studies have been conducted on the primary water chemistry to reduce the amount of crud in the primary circuit to avoid radioactivity buildup and unexpected power transition in the plant. However, experiments on the crud are restricted in the laboratory because the crud is a highly radioactive material. The objective of this study is to develop a test method for simulating the deposition of crud in a nuclear power plant

2010-10-01

113

Solution-based characterization of surface-enhanced Raman response of single scattering centers  

Energy Technology Data Exchange (ETDEWEB)

We demonstrate the rapid optical characterization of large numbers of individual metal nanoparticles freely diffusing in colloidal solution by confocal laser spectroscopy. We find that hollow gold nanospheres and solid silver nanoparticles linked with a bifunctional ligand, both designed nanostructures, exhibit significantly higher monodispersity in their Rayleigh and Raman scattering response than randomly aggregated gold and silver nanoparticles. We show that measurements of rotational diffusion timescales allow sizing of particles significantly more reliably than can be obtained using translational diffusion timescales.

2008-03-06

114

Sol-gel approaches for solid electrolytes and electrode materials. Technical report  

Energy Technology Data Exchange (ETDEWEB)

Sol-gel chemistry has a great many potential applications in the preparation of unique electrochemical materials, from non-equilibrium transition metal oxides which may be of use as high energy density electrodes, to high-surface area mixed oxides which may possess high proton conductivity, to novel composite structures consisting of inorganic gels in combination with organic, electronic, and ionic conductors. This paper reviews prior work on proton conduction in gel systems and presents recent work regarding electrode materials prepared by sol-gel methods and inorganic-organic materials.

1995-07-14

115

Room-temperature phosphorescence of nitrogen heterocycles and aromatic amines  

Energy Technology Data Exchange (ETDEWEB)

Room-temperature phosphorescence (RTP) has generated considerable interest over the past several years. Several materials have been used to induce RTP from a variety of compounds. However, there is still a need to test additional materials and experimental conditions for RTP so the maximum sensitivity and selectivity can be obtained. In this work, three solid surfaces and several experimental conditions were tested for RTP of nitrogen heterocycles and aromatic amines. Nitrogen heterocycles and aromatic amines are an important class of compounds as shown by work in areas such as environmental research and coal liquefaction research. 18 references.

1982-01-01

116

Mechanisms of Alloy 800 corrosion in helium  

International Nuclear Information System (INIS)

Cr_2O_3 scales are found to form on Alloy 800 and a similar pure ternary alloy in air, and 1 and 50 atm. helium containing oxidizing impurities typical of those in an SGHTR. The strong temperature dependence and neglibible helium overpressure dependence indicate that gas transport through the scales is not rate controlling. Surface oxidation rates are therefore controlled by solid state diffusion and the low oxygen partial pressure dependence of the oxidation rate in Alloy 800 is ascribed to the presence of extrinsic defects in the Cr_3O_3 (due to doping by alloying elements) or to the presence of short circuit diffusion paths. (Auth.).

117

Influence of laserglaze on microstructure and wear resistance of a cast Ni-base superalloy  

Energy Technology Data Exchange (ETDEWEB)

The effect of high-energy-density laser surface melting on the morphology and properties of a cast Ni-based superalloy containing 33 wt percent Mo and 17 wt percent W is investigated experimentally. Significant improvements in the hardness and the wear resistance in both dry and acid environments are atttributed to the elimination of segregation in the laser-treated zone, where solid solubility increases, crystalline structure becomes finer, and the fine dendritic, cellular dendritic, cellular, and plane-front solidification structures are evenly distributed.

1984-04-18

118

The inertial dynamics of thin film flow of non-Newtonian fluids  

CERN Document Server

Consider the flow of a thin layer of non-Newtonian fluid over a solid surface. I model the case of a viscosity that depends nonlinearly on the shear-rate; power law fluids are an important example, but the analysis here is for general nonlinear dependence. The modelling allows for large changes in film thickness provided the changes occur over a large enough lateral length scale. Modifying the surface boundary condition for tangential stress forms an accessible base for the analysis where flow with constant shear is a neutral critical mode, in addition to a mode representing conservation of fluid. Perturbatively removing the modification then constructs a model for the coupled dynamics of the fluid depth and the lateral momentum. For example, the results model the dynamics of gravity currents of non-Newtonian fluids even when the flow is not very slow.

2007-01-01

119

Role of temperature in the spontaneous precipitation of calcium sulfate dihydrate  

Energy Technology Data Exchange (ETDEWEB)

The spontaneous precipitation of calcium sulfate in supersaturated solutions over the temperature range between 25.0 and 80.0 C was investigated by monitoring the solution specific conductivity during desupersaturation. From measurements of the induction times preceding the onset of precipitation the surface energy of the forming solid, identified as gypsum, was found between ca. 12 and 25 mJ/m{sup 2} for the temperature range between 80.0 and 25.0 C, respectively. Kinetics analysis showed that over 50 C it is possible that anhydrous calcium sulfate is forming as a transient phase converting into the more stable calcium sulfate dihydrate. The linear dependence of the rates of precipitation on the relative solution supersaturation suggested a mechanism according to which the growth units are integrated into the active sites of the supercritical nuclei by surface diffusion. According to the morphological examination of the ...

1999-02-16

120

Process for repairing a cryogenic heat exchanger  

International Nuclear Information System (INIS)

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

1987-10-13

121

Photocatalytic oxidation of toluene to benzaldehyde over anatase TiO2 hollow spheres with exposed {001} facets  

British Library Electronic Table of Contents (United Kingdom)

A new series of anatase TiO2 hollow structures were prepared by a facile hydrothermal process. When the hydrothermal time was increased from 20min to 72h, the resulting TiO2 solid spheres gradually transformed into TiO2 hollow spheres with higher surface crystallinity and exposed {001} facets. The as-prepared TiO2-72h sample exhibited the highest activity comparing to other TiO2-based samples and commercial product Degussa P-25 towards the selective photocatalytic oxidation of toluene to benzaldehyde. Such great photocatalytic performance was mainly attributed to enhanced UV-adsorption and better charge separation efficiency due to higher surface crystallinity of TiO2-72h.

2011-01-01

122

Mechanism of physical transformations of mineral matter in the blast furnace coke with reference to its reactivity and strength  

Science.gov (United States)

Examinations of polished and dry cut sections of feed and tuyere coke revealed some possible mechanisms for the physical influence of mineral compounds on the reactivity and strength of coke. It was observed that rounded particles of mineral phases that are exposed to the pore walls and surface of coke at high temperature create an inorganic cover, thus reducing the surface available for gas-solid reactions. The particles of mineral matter that have a low melting point and viscosity can affect the coke at earlier stages in the blast furnace process, acting in the upper parts of the blast furnace (BF). The temperature-driven redistribution of mineral phases within the coke matrix probably leads to the creation of weak spots and in general to anisotropy in its properties, thus reducing its strength. 9 refs., 2 figs., 1 tab.

2006-12-15

123

Increased performance of bearings using TiC-coated balls  

Energy Technology Data Exchange (ETDEWEB)

The main purpose of solid or fluid lubricants in ball-bearings is to separate the balls and races from contacting each other in so-called asperity collisions. Steel to steel contacts lead to microwelds which roughen functional rolling-contacting surfaces and deteriorate the lubricant. By using balls with a ceramic TiC coating, two goals are achieved. First, there are fewer asperity collisions because of the extreme smoothness of the high precision polished TiC coated balls. Second, if collisions do occur, there is practically no microwelding taking place, leaving the surfaces and the lubricant in good condition. Examples are given where the bearing lifetime is increased up to 10 times if the steel balls are replaced by TiC-coated balls. (orig.).

1993-11-01

124

Formation of complex Langmuir and Langmuir-Blodgett films of water soluble rosebengal  

British Library Electronic Table of Contents (United Kingdom)

This communication reports the formation of complex Langmuir monolayer at the air-water interface by charge transfer types of interaction with the water soluble N-cetyl Formula Not Shown -trimethyl ammonium bromide (CTAB) molecules doped with rosebengal (RB), with the stearic acid (SA) molecules of a preformed SA Langmuir monolayer. The reaction kinetics of the formation of RB-CTAB-SA complex monolayer was monitored by observing the increase in surface pressure with time while the barrier was kept fixed. Completion of interaction kinetics was confirmed by FTIR study. This complex Langmuir films at the air-water interface was transferred onto solid substrates at a desired surface pressure to form multilayered Langmuir-Blodgett films. Spectroscopic characterizations reveal some molecular lev...

2007-01-01

125

Design of sediment-control measures for small areas in surface coal mining. Draft report  

Energy Technology Data Exchange (ETDEWEB)

The manual provides design information for four groups of sediment control structures and treatments which are suitable for use on small areas in surface coal mining. A detailed design procedure is given for each group which will estimate the total amount of settleable solids from a small area with a sediment control structure or treatment for a specific design storm. A procedure is also given for estimating the mean annual sediment yield from a small area. Information on design, installation, maintenance and cost is given for each sediment control measure. Methods for determining the maximum allowable area for each sediment control measure and for design of combined sediment control systems are presented. The design procedures contain numerous nomographs, graphs, and worksheets to facilitate the use of the design procedure. The sediment control measures, design procedures, and materials in the manual are applicable to coal-bearing regions of ...

1982-04-01

126

Design of sediment-control measures for small areas in surface coal mining  

Energy Technology Data Exchange (ETDEWEB)

The manual provides design information for four groups of sediment control structures and treatments which are suitable for use on small areas in surface coal mining. A detailed design procedure is given for each group which will estimate the total amount of settleable solids from a small area with a sediment control structure or treatment for a specific design storm. A procedure is also given for estimating the mean annual sediment yield from a small area. Information on design, installation, maintenance and cost is given for each sediment control measure. Methods for determining the maximum allowable area for each sediment control measure and for design of combined sediment control systems are presented. The design procedures contain numerous nomographs, graphs, and worksheets to facilitate the use of the design procedure. The sediment control measures, design procedures, and materials in the manual are applicable to coal bearing regions of ...

1982-08-01

127

Alkylaldehyde-bisulfite adducts as cleavable surfactants  

British Library Electronic Table of Contents (United Kingdom)

Alkylaldehyde-bisulfite adducts with octyl, decyl, and dodecyl groups (CnS: n=8,10,12) were synthesized and the surface-active properties of the water-soluble compounds were compared. Exchange of the counter anions of C10S and C12S from sodium to tetramethylammonium solubilized them in water. The latter ammonium salt (C12S-QA) had surface activities as good as a classical surfactant, sodium dodecylsulfate, and dissociated promptly in weakly basic solution at room temperature to be a non-surfactant. It was also found that C12S-QA solubilized a hydrophobic substrate (solid), N,N-dimethyl-3-nitroaniline, in water and then separated it as a precipitate after alkali treatment.

2007-01-01

128

A study of methyl formate in astrochemical environments  

CERN Document Server

Several complex organic molecules are routinely detected in high abundances towards hot cores and hot corinos. For many of them, their paths of formation in space are uncertain, as gas phase reactions alone seem to be insufficient. In this paper, we investigate a possible solid-phase route of formation for methyl formate (HCOOCH3). We use a chemical model updated with recent results from an experiment where simulated grain surfaces were irradiated with 200 keV protons at 16 K, to simulate the effects of cosmic ray irradiation on grain surfaces. We find that this model may be sufficient to reproduce the observed methyl formate in dark clouds, but not that found in hot cores and corinos.

2011-01-01

129

Surface physics with cold and thermal neutron reflectometry. Progress report, April 1, 1991--September 30, 1993  

Energy Technology Data Exchange (ETDEWEB)

Within the past two and one half years of the project ``Surface Physics With Cold and Thermal Neutron Reflectometry`` a new thermal neutron reflectometer was constructed at the Rhode Island Nuclear Science Center (RINSC). It was used to study various liquid and solid surfaces. Furthermore, neutron reflection experiments were be un at different laboratories in collaboration with Dr. G.P. Fetcher (at Argonne National Laboratory), Dr. T. Russell (IBM Almaden) and Drs. S.K. Satija and A. Karim (at the National Institute for Standards and Technology). The available resources allowed partial construction of an imaging system for ultracold neutrons. It is expected to provide an extremely high resolution in momentum and energy transfer in surface studies using neutron reflectometry. Much of the work reported here was motivated by the possibility of later implementation at the planned Advanced Neutron Source at ...

1993-09-01

130

Sediment trap fluxes and benthic recycling of organic carbon, polycyclic aromatic hydrocarbons, and polychlorobiphenyl congeners in Lake Superior  

Energy Technology Data Exchange (ETDEWEB)

Sediment trap fluxes of solids, organic carbon, polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs) were measured in Lake Superior in 1984 and 1985. Mass fluxes from surface waters ranged from 0.14 to 1.1 g/m{sup 2}{center dot}day and increased near the lake floor due to resuspension of surficial sediment and horizontal transport in the benthic nepheloid layer. Organic matter fluxes from surface water ranged from 60 to 90 mg of C/m{sup 2}{center dot}day, with {approximately}5% of organic carbon settling from surface waters accumulating in bottom sediments. Concentrations of PCBs and PAHs are enriched 10-100 times on settling particles relative to those on suspended particles. Resultant settling fluxes are 10-100 times greater for several PCB and PAH compounds than net accumulation rates in bottom sediments, indicating the effective and rapid recycling in the benthic region. ...

1991-03-01

131

Simulation of uranium oxides reduction kinetics by hydrogen. Reactivities of germination and growth; Modelisation de la cinetique de reduction d`oxydes d`uranium par l`hydrogene. Reactivites de germination et de croissance  

Energy Technology Data Exchange (ETDEWEB)

The aim of this work is to simulate the reduction by hydrogen of the tri-uranium octo-oxide U{sub 3}O{sub 8} (obtained by uranium trioxide calcination) into uranium dioxide. The kinetics curves have been obtained by thermal gravimetric analysis, the hydrogen and steam pressures being defined. The geometrical modeling which has allowed to explain the trend of the kinetics curves and of the velocity curves is an anisotropic germination-growth modeling. The powder is supposed to be formed of spherical grains with the same radius. The germs of the new UO{sub 2} phase appear at the surface of the U{sub 3}O{sub 8} grains with a specific germination frequency. The growth reactivity is anisotropic and is very large in the tangential direction to the grains surface. Then, the uranium dioxide growths inside the grain and the limiting step is the grain surface. The variations of the growth reactivity and of the germination specific ...

1997-12-04

133

The use of calcium silicate bricks for retrospective dosimetry  

International Nuclear Information System (INIS)

The suitability of calcium silicate bricks (CSBs) for the retrospective measurement of gamma dose using luminescence techniques has been investigated. Bricks of this type are distinguished from fired clay bricks by containing negligible clay and requiring comparatively low temperature treatment during manufacture. They have been used widely in the construction f buildings in the Former Soviet Union since the 1970s but hitherto have not been used for retrospective dosimetry measurements. A procedure based on the se of the 210 deg. C thermoluminescence (TL) peak of quartz was tested with granular quartz extracted from three types of CSB, one of which had been taken from a settlement downwind of Chernobyl. The degree to which the residual geological TL signal within the temperature range of the 210 deg. C L peak had been reduced during manufacture varied with brick type; the levels of residual TL corresponded, in the samples tested, to absorbed ...

2004-02-01

134

The uranium deposits of Ontario  

International Nuclear Information System (INIS)

The principal types of uranium deposits in Ontario are carbonatites and fenites, alkalic volcanic rocks, pegiatites, calc-silicate rocks, pyritic quartz-pebble conglomerates, polymictic conglomerates and some pelitic rocks, and various 'pitchblende' deposits including late Precambrian unconformities, possibly late Precambrian diabase dikes, and other unconformities: carbonates, sandstones, lignites, and semi-pelitic rocks of middle and upper Precambrian age. Only red unzoned pegmatite and the pyritic quartz-pebble conglomerate have supported production. Ontario reasonably assured and estimated resources in the economic and subeconomic categories in 1977 amounted to 553 000 tonnes U, and 1977 production was 4000 tonnes U. Measured, indicated, and inferred resources in the Elliot Lake - Agnew Lake area are at least 400 000 tonnes U. The latter deposits are also a significant thorium resource. Geological features reflecting major changes in ...

1990-03-15

135

Kinetics of the stress induced phase transition in quartz by real-time neutron scattering  

International Nuclear Information System (INIS)

Complete text of publication follows. The stability regime of the incommensurate phase of quartz is influenced by uniaxial stress. Hence, the phase transition can be induced under isothermal conditions by the application of external mechanical forces. Using real-time neutron scattering the time evolution of structural changes is investigated id detail during stress variations. The time dependent behaviour of the satellite reflection is compared with that one of the fundamental Bragg reflection which - via primary extinction - gives information about the perfection of the crystal. On increasing stress the perfection of the lattice is destroyed immediately while the modulated structure is built up with a delay of about 1 s. Decreasing the stress leads to a reverse behaviour. Moreover, there is evidence that under periodical load residual non-relaxed strain fields survive leading to a different temperature dependence as compared to static conditions. This finding is ...

1999-09-01

136

Open-system Behavior during Pluton-Wall-rock Interaction as Constrained from a Study of Endoskarns in the Sierra Nevada Batholith, California  

British Library Electronic Table of Contents (United Kingdom)

Crustal xenoliths (pyroxenites and plagioclase + quartz + pyroxene lithologies) from the Quaternary Big Pine volcanic field on the eastern flank of the Sierra Nevada Batholith in California (USA) represent the products of metasomatic reaction between the margins of a Cretaceous granodioritic pluton and Paleozoic marbles, possibly at mid-crustal depths based on the equilibration temperatures recorded by Ti-in-quartz geothermometry. This interpretation is based on the presence of plagioclase showing relict plutonic textures, pyroxenite characterized by nearly pure diopside clinopyroxene, recrystallized plagioclase with anomalously high anorthite content, textures indicating replacement of plagioclase by clinopyroxene (and vice versa), `ghost' plagioclase rare earth element signatures in some...

2011-01-01

137

Silica Polyamine Composites: New Supramolecular Materials for Cation and Anion Recovery and Remediation  

Energy Technology Data Exchange (ETDEWEB)

The surface coverage of amorphous silica gels used in the synthesis of silica polyamine composites has been investigated by 29Si NMR. By diluting the polyamine anchor silane, chloropropyl trichlorosilane, with methyl trichlorosilane it was found that surface coverage could be markedly improved for a range of amine polymers after grafting to the silica surface. The commensurate decrease in the number of anchor points and increase in the number of free amines results in an increase in metal capacity and/or an improvement in capture kinetics. Solid state CPMAS-13C NMR has been employed to investigate the structure and metal ion binding of a series of these composite materials. It is reported that the highly branched polymer, poly(ethyleneimine) (PEI) exhibits much broader 13C NMR resonances than the linear polymers poly(allylamine) (PAA) and poly(vinylamine) (PVA). These results are understood in terms of ...

2006-03-01

138

Pathway and Surface Mechanism Studies of 1,3-butadiene Selective Oxidation Over Vanadium-Molybdenum-Oxygen Catalysts  

Energy Technology Data Exchange (ETDEWEB)

The partial oxidation of 1,3-butadiene has been investigated over VMoO catalysts synthesized by sol-gel techniques. Surface areas were 9-14 m{sup 2}/g, and compositions were within the solid solution regime, i.e. below 15.0 mol % MoO{sub 3}/(MoO{sub 3} + V{sub 2}O{sub 5}). Laser Raman Spectroscopy and XRD data indicated that solid solutions were formed, and pre- and post-reaction XPS data indicated that catalyst surfaces contained some V{sup +4} and were further reduced in 1,3-butadiene oxidation. A reaction pathway for 1,3-butadiene partial oxidation to maleic anhydride was shown to involve intermediates such as 3,4-epoxy-1-butene, crotonaldehyde, furan, and 2-butene-1,4-dial. The addition of water to the reaction stream substantially increased catalyst activity and improved selectivity to crotonaldehyde and furan at specific reaction temperatures. At higher water addition concentrations, furan ...

2002-05-27

139

Flow Vaporization of CO{sub 2} in Microchannel Tubes  

Energy Technology Data Exchange (ETDEWEB)

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

2002-07-01

140

Photodegradation and photostabilization of weathered wood flour filled polyethylene composites  

Science.gov (United States)

Wood plastic composites (WPCs) have gained popularity as building materials because of their usefulness in replacing solid wood in a variety of applications. These composites are promoted as being low-maintenance, high-durability products. However, it has been shown that WPCs exposed to weathering may experience a color change and/or loss in mechanical properties. An important requirement for building materials used in outdoor applications is the retention of their aesthetic qualities and mechanical properties during service life. Therefore, it is critical to understand the photodegradation mechanisms of WPCs exposed to UV radiation and to develop approaches to stabilize these composites against ultraviolet light. In this dissertation, the surface chemistries of weathered composites (both unstabilized and stabilized) as well as the effect of weathering on the color fade and the retention of mechanical properties were characterized. Since ...

2003-01-01

141

Identifying surface structural changes in layered Li-excess nickel manganese oxides in high voltage lithium ion batteries: A joint experimental and theoretical study  

Energy Technology Data Exchange (ETDEWEB)

High voltage cathode materials Li-excess layered oxide compounds Li[Ni{sub x}Li{sub 1/3-2x/3}Mn{sub 2/3-x/3}]O{sub 2} (0 < x < 1/2) are investigated in a joint study combining both computational and experimental methods. The bulk and surface structures of pristine and cycled samples of Li[Ni{sub 1/5}Li{sub 1/5}Mn{sub 3/5}]O{sub 2} are characterized by synchrotron X-Ray diffraction together with aberration corrected Scanning Transmission Electron Microscopy (a-S/TEM). Electron Energy Loss Spectroscopy (EELS) is carried out to investigate the surface changes of the samples before/after electrochemical cycling. Combining first principles computational investigation with our experimental observations, a detailed lithium de-intercalation mechanism is proposed for this family of Li-excess layered oxides. The most striking characteristics in these high voltage high energy density cathode materials are (1) formation of tetrahedral lithium ...

2011-09-06

142

Heterogeneous catalytic process for alcohol fuels from syngas. Fifth quarterly technical progress report, January--March 1993  

Energy Technology Data Exchange (ETDEWEB)

As stated last quarter, we discovered potassium as an impurity in the mixed metal oxides. The potassium was probably incorporated into the solid during the coprecipitation using K{sub 2}CO{sub 3}. Currently NH{sub 4}OH is being used as the precipitating base. We have discovered that the precipitation agent influences the surface composition of the mixed-metal oxides. Chemical analysis of the surface and bulk compositions showed significant differences in surface compositions of the K{sub 2}CO{sub 3} and NH{sub 4}OH precipitated catalysts. In TPR experiments we have discovered that the precipitating pH markedly affects the reducibility of the ZnMnCr oxides. This shows that the choice of base as well as the pH strongly affects the surface composition of the mixed metal catalysts. Additional studies are in progress in which we are studying how the precipitating agents affect the ...

1993-12-01

143

Focused ion beam repair: staining of photomasks and reticles  

Energy Technology Data Exchange (ETDEWEB)

Focused ion beam (FIB) repair of chromium defects on photomasks and reticles leaves a post repair stain in the quartz substrate. The wavelength dependent absorption properties of typical stained regions have been measured, showing transition losses up to 80% in the deep uv. A simple model is in good qualitative agreement with the experimental results. (author).

1993-07-14

145

Study on separation of CO2 gas by TSS (thermal swing sublimation) method. Part 2; TSS ho (Thermal Swing Sublimation: ondo swing shokaho) ni yoru tansan gas bunri no kenkyu. 2  

Energy Technology Data Exchange (ETDEWEB)

TSS (thermal swing sublimation) method was studied which uses vaporization heat and sensible heat of LNG for solidification and separation of CO2 gas in waste gases of LNG-fired combined cycle power generation system. In experiment, the mixed gas composed of CO2, H2O and N2 was used for simulating waste gas of LNG-fired combined cycle power generation systems, and the growth behavior of ice and dry ice was studied for developing dry ice making technology under low-temperature condition. As the experimental result, the following were clarified: various crystal structures depending on cooling temperature, the effect of gas flow rate on peeling of surface precipitated solids, and solidification characteristics of H2O/CO2 mixed gas. The growth rate of precipitated solid film thickness decreased with an increase in gas flow rate, while increased with CO2 concentration. The shape of a dry ice sublimator similar to that of a ...

1997-03-21

146

Production of a cellulolytic enzyme system in mixed-culture solid-state fermentation of soybean hulls supplemented with wheat bran  

British Library Electronic Table of Contents (United Kingdom)

Solid-state fermentation of soybean hulls supplemented with wheat bran using a co-culture of Trichoderma reesei and Aspergillus oryzae was performed. Three parameters - initial moisture content, incubation temperature, and initial pH - were optimized in culture flasks using response surface methodology. Parameter optimization was carried out with respect to filter paper activity and b-glucosidase activity in the culture. Temperature of 30^oC, pH of 5, and moisture content of 70% were found to be optimum. Optimized parameters were used for laboratory scale-up in static tray fermenters. The maximum filter paper activity of 10.7FPU/g-ds and b-glucosidase of 10.7IU/g-ds were obtained after 96-h incubation period in static tray fermenters in agreement with optimized activities at shake flask le...

2010-01-01

147

Electrode reaction of Pu{sup 3+}/Pu couple in LiCl-KCl eutectic melts: comparison of the electrode reaction at the surface of liquid Bi with that at a solid Mo electrode  

Energy Technology Data Exchange (ETDEWEB)

The electrode reaction of Pu{sup 3+}/Pu couple at the interface between LiCl-KCl eutectic melt containing PuCl{sub 3} and liquid Bi phase was investigated by cyclic voltammetry at 723, 773 and 823 K. For comparison, the system was also studied using a solid Mo electrode in place of the liquid Bi electrode. It was found that the electrode reaction of Pu{sup 3+}/Pu couple at the Bi electrode was almost reversible. The redox potentials of Pu{sup 3+}/Pu couple at the liquid Bi electrode in the LiCl-KCl eutectic melt containing 0.87 wt% PuCl{sub 3} (0.0014 mole fraction) at 723, 773 and 823 K were observed to be more positive by 0.575, 0.572 and 0.566 V, respectively, than those at the Mo electrode. These differences in potential were thermodynamically analyzed by assuming a lowering of the activity of Pu in Bi phase according to the alloy formation of PuBi{sub 2}. (author)

2001-01-01

148

Effect of various coal contaminants on the performance of solid oxide fuel cells: Part II. ppm and sub-ppm level testing  

Energy Technology Data Exchange (ETDEWEB)

The poisoning effects of various trace contaminants in the coal-derived syngas stream at ppm and sub-ppm level on the performance of Ni-YSZ/YSZ/LSM solid oxide fuel cells were studied at extended duration. The thermochemical nature of impurities such as PH{sub 3}(g) and CH{sub 3}Cl(g) in presence and absence of water steam was analyzed by a high temperature mass spectrometer. Only less than half of PH{sub 3}(g) is hydrolyzed, and CH{sub 3}Cl(g) also co-exist with HCl(g). After a certain duration of exposure, 1 ppm AsH{sub 3}(g), 0.5 ppm PH{sub 3}(g), and 2.5 ppm CH{sub 3}Cl(g) all caused some degree of degradation to the power density at 750 C. Whereas 1 ppm of H{sub 2}S(g) resulted in immediate performance loss. The mechanisms of degradation are mainly divided into two categories: surface adsorption effect (for S and Cl) and bulk reaction effect (for As and P). The controversies regarding the poisoning effect and mechanism of S are also ...

2009-09-05

149

Diffusion research between Ni3Al coating and titanium alloy produced by plasma spraying process  

British Library Electronic Table of Contents (United Kingdom)

A Ni3Al coating was prepared by plasma spraying technique on the surface of titanium alloy. Ni-Al mixed powders, coatings and reaction products were investigated by scanning electron microscope, EDS, DSC and XRD. A tight bonding between the coating and the substrate was formed. The X-ray diffraction analysis of the patterns showed that the coating not only had Ni3Al phase, but also had NiO and Al2O3 phase microcontent. Comparing Ni coated Al to Ni3Al at 900^oC, the diffusion was stronger and the diffusion layer was thicker. A minute pore structure was formed at 1200^oC in the front edge of solid-state reaction layer. So Ni3Al restrained the solid-state reaction of the coating with the substrate, and as a whole weakened the entry of oxygen atoms into the substrate and quenched the out-diffu...

2010-01-01

150

Design of experiment approach applied to reducing and oxidizing tolerance of anode supported solid oxide fuel cell. Part I: Microstructure optimization  

British Library Electronic Table of Contents (United Kingdom)

The main drawback of Ni/YSZ anode supports for solid oxide fuel cell application is their low tolerance to reducing and oxidizing (RedOx) atmosphere changes, owing to the Ni/NiO volume variation. This work describes a structured approach based on design of experiments for optimizing the microstructure for RedOx stability enhancement. A full factorial hypercube design and the response surface methodology are applied with the variables and their variation range defined as: (1) NiO proportion (40-60wt% of the ceramic powders), (2) pore-former proportion (0-30wt% corresponding to 0-64vol.%), (3) NiO particle size (0.5-8mm) and (4) 8YSZ particle size (0.6-9mm). To obtain quadratic response models, 25 different compositions were prepared forming a central composite design. The measured responses...

2011-01-01

151

Cellulolytic Enzymes Production via Solid-State Fermentation: Effect of Pretreatment Methods on Physicochemical Characteristics of Substrate.  

Science.gov (United States)

We investigated the effect of pretreatment on the physicochemical characteristics-crystallinity, bed porosity, and volumetric specific surface of soybean hulls and production of cellulolytic enzymes in solid-state fermentation of Trichoderma reesei and Aspergillus oryzae cultures. Mild acid and alkali and steam pretreatments significantly increased crystallinity and bed porosity without significant change inholocellulosic composition of substrate. Crystalline and porous steam-pretreated soybean hulls inoculated with T. reesei culture had 4 filter paper units (FPU)/g-ds, 0.6?IU/g-ds ?-glucosidase, and 45?IU/g-ds endocellulase, whereas untreated hulls had 0.75?FPU/g-ds, 0.06?IU/g-ds ?-glucosidase, and 7.29?IU/g-ds endocellulase enzyme activities. In A. oryzae steam-pretreated soybean hulls had 47.10?IU/g-ds endocellulase compared to 30.82?IU/g-ds in untreated soybean hulls. Generalized linear statistical model fitted to enzyme activity data ...

2011-06-15

152

A single sorbent for tetracycline enrichment and subsequent solid-matrix time-resolved luminescence  

Energy Technology Data Exchange (ETDEWEB)

The aim of this study was to search for a sorbent that could act as an extraction phase and as a support for solid-matrix time-resolved luminescence (SMTRL). Four potential sorbents were investigated for this purpose using tetracycline (TC) as a model analyte. Sorbents prepared from C18 silica gel or calcium cross-linked pectin gel were able to extract TC from dilute solutions. Europium(III)-TC complex adsorbed on the surface of C18 generated the most intense TRL signal when measured at {lambda}{sub ex} = 388 nm and {lambda}{sub em} = 615 nm. This method achieved a 1 ng/ml limit of detection (LOD) with a 100 {mu}l sample solution in a repeated spotting mode. Hyphenation of sorbent extraction and SMTRL was demonstrated using C18. This method is suitable for screening of TC in foods or aqueous solutions and can be extended to other luminescent lanthanide-chelating analytes in physiological or environmental samples.

2005-01-10

153

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

International Nuclear Information System (INIS)

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

2004-04-21

154

Results and recommendations from studies of basic handling characteristics of solid biomass fuels  

Energy Technology Data Exchange (ETDEWEB)

Main results are summarised for a project carried out with the aim of increasing the knowledge of relations between handling characeristics and properties such as moisture content, particle size and shape etc. Handling characteristics that were studied: angle of repose, friction between fuel and different surfaces, the fuel`s tendency to bridge across openings, and its freezing characteristics. Some forty solid biomass fuels were studied, mainly wood fuels, with particle sized from 1 to 200 mm. New methods were developed for measurement of bridging across openings and freezing characeristics. The angle of repose varied between 25 and 55 deg. The particle shape had a significant influence, a high ratio of length/thickness gave a high angle of repose. When the fuel moisture content was increased the angle of repose first increased, then decreased, and finally increased again. The particle size had no influence. The friction depended more on the ...

1996-12-31

155

Catalytic hydrothermal gasification of biomass for the production of synthetic natural gas[Dissertation 17100  

Energy Technology Data Exchange (ETDEWEB)

Energy from biomass is a CO{sub 2} neutral, sustainable form of energy. Anaerobic digestion is an established technology for converting biomass to biogas, which contains around 60% methane, besides CO{sub 2} and various contaminants. Most types of biomass contain material that cannot be digested; in woody biomass, this portion is particularly high. Therefore, conventional anaerobic digestion is not suited for the production of biogas from woody biomass. While wood is already being converted to energy by conventional thermal methods (gasification with subsequent methanation), dung, manure, and sewage sludge represent types of biomass whose energy potential remains largely untapped (present energetic use of manure in Switzerland: 0.4%). Conventional gas phase processes suffer from a low efficiency due to the high water content of the feed (enthalpy of vaporization). An alternative technology is the hydrothermal gasification: the water contained within the biomass serves as reaction ...

2007-07-01

158

Solid state chemistry in catalysis  

Energy Technology Data Exchange (ETDEWEB)

Correlations between structural aspects of solid materials and their behavior as catalysts are relatively recent. This 20-chapter book focuses on understanding of solid-state mechanisms in heterogeneous catalysis and relationship between catalytic behavior and solid state structure, emphasizing catalysis with oxides, sulfides, and zeolites.

1985-01-01

161

Tris(2,2prime-bipyridyl)ruthenium(II) Electrogenerated Chemiluminescence Sensor Based on Platinized Carbon Nanotube-Zirconia-Nafion Composite Films  

British Library Electronic Table of Contents (United Kingdom)

Mesoporous films of platinized carbon nanotube-zirconia-Nafion composite have been used for the immobilization of tris(2,2prime-bipyridyl)ruthenium (II) (Ru(bpy)32+) on an electrode surface to yield a solid-state electrogenerated chemiluminescence (ECL) sensor. The composite films of Pt-CNT-zirconia-Nafion exhibit much larger pore diameter (3.55 nm) than that of Nafion (2.82 nm) and thus leading to much larger ECL response for tripropylamine (TPA) because of the fast diffusion of the analyte within the films. Due to the conducting and electrocatalytic features of CNTs and Pt nanoparticles, their incorporation into the zirconia-Nafion composite films resulted in the decreased electron transfer resistance within the films. The present ECL sensor based on the Pt-CNT-zirconia-Nafion gave a lin...

2010-01-01

162

Study on the solid state reaction between bilayered Pd/Au films and silicon substrates  

British Library Electronic Table of Contents (United Kingdom)

Bilayers of pure palladium and gold films were evaporated alternatively on (100) and (111) monocrystalline silicon substrates. After annealing, in a vacuum furnace from 100 to 650degreeC during 30min, the growth sequence of the Pd2Si and PdSi phases that evolved as the result of the diffusion reaction was examined by means of Rutherford backscattering spectrometry (RBS), X-ray diffraction (XRD), whereas the surface morphology was investigated by scanning electron microscopy (SEM) technique. The effect of the intermediate gold layer is investigated in order to test its effectiveness as barrier for Cu and Si atoms interdiffusion and its influence on the morphology of the formed palladium silicides. The effect of substrate orientation on the palladium silicides growth and formation was also e...

2006-01-01

163

Shock stand-off distance of a solid sphere decelerating in transonic velocity range  

British Library Electronic Table of Contents (United Kingdom)

The shock stand-off distance of a spherical model flying with transonic speeds is determined through numerical simulations. The model decelerates due to drag forces caused by the pressure and viscous shear stress at the model surface. Two-dimensional axisymmetric numerical codes with numerical grids fixed to the flying spherical model are used in the simulations. Numerically determined shock stand-off distances are compared with experimental data obtained in a previous study as well as with those obtained in our ballistic-range experiments. The numerical results and the experimental data are found to be in good agreement. In addition, the time-dependent shock stand-off distance of a decelerating model is investigated.

2011-01-01

164

Redistribution of implanted dopants after metal-silicide formation  

Science.gov (United States)

The redistribution of implanted As and Sb following metal-silicide formation of Pt, Pd, and Ni has been studied. The phases of the silicides used were PtSi, Pd/sub 2/Si, and NiSi. Investigations with Rutherford backscattering analysis showed that after the formation of the silicides, the Sb was always found in the silicide layer near the surface of the samples, whereas PtSi and Pd/sub 2/Si caused a partial rejection of As for implanted doses of 2 x 10/sup 15/ cm/sup -2/ and higher. No rejection of As was found after the formation of NiSi. The results are discussed in terms of solid solubilities and impurity-metal compound formation. The data presented has implications in the fabrication of Ohmic contacts and the adjustments of the heights of Schottky barriers on silicon.

1978-12-01

165

Redistribution of implanted dopants after metal-silicide formation  

International Nuclear Information System (INIS)

The redistribution of implanted As and Sb following metal-silicide formation of Pt, Pd, and Ni has been studied. The phases of the silicides used were PtSi, Pd_2Si, and NiSi. Investigations with Rutherford backscattering analysis showed that after the formation of the silicides, the Sb was always found in the silicide layer near the surface of the samples, whereas PtSi and Pd_2Si caused a partial rejection of As for implanted doses of 2 x 10"1"5 cm"-"2 and higher. No rejection of As was found after the formation of NiSi. The results are discussed in terms of solid solubilities and impurity-metal compound formation. The data presented has implications in the fabrication of Ohmic contacts and the adjustments of the heights of Schottky barriers on silicon.

166

Overview of industrial applications of induction; L'induction au service de l'industrie: panorama des applications industrielles  

Energy Technology Data Exchange (ETDEWEB)

Because power requirements in induction heating applications are largely dependent on the physical properties of the product to be heated, inducting, heating is mainly used in steelwork applications, for the manufacture of finished or semi-finished parts. Applications here cover five main types of steelworks operation: smelting, heating prior to forming, heat treatment, surface treatment, and assembly process. At the same time, technological progress has opened up innovative applications in sectors such as chemical and agro-food industries. Other emerging applications for induction include direct forming of liquid metal, wholly or partially replacing mechanical transformations on solid metal. Techniques include electromagnetic forming, continuous cold-crucible casting, electromagnetic mixing, flow control by continuous magnetic field, and production of intense sliding fields (pumps, flow regulation). (author)

2004-05-01

167

On the anatomy of the adsorption heat versus loading as a function of temperature and adsorbate for a graphitic surface  

British Library Electronic Table of Contents (United Kingdom)

In this paper we review and classify the various patterns of isosteric heat versus loading for adsorption of gases on graphitised thermal carbon black at temperatures ranging from below the 3D triple point to temperatures above it, but less than the 3D critical point. We have identified the features of heat curve and highlighted the microscopic origin of these features. The patterns vary with temperature and with the relative strength of the fluid-fluid interaction and solid-fluid interaction. For simple adsorptives (by simple we meant there is no strong association between fluid particles), the heat curve is typified by fluid-fluid attraction and layering phenomena. For adsorptives showing strong association such as water, ammonia and methanol, the heat curve essentially begins below the ...

2008-01-01

168

On the Approach to Spherical Harmonics by Maxwell, Thomson and Tait  

CERN Document Server

We present a unified self-consistent review of the approach to spherical harmonics developed in the second half of the 19th century by Maxwell and by Thomson and Tait. We remark how this spherical coordinate-free approach straightforwardly leads to physically very important results of the theory of solid and surface harmonics which become rather tedious to work out when using spherical coordinates and associated Legendre functions. These results include, among others, the addition theorem, spherical wave expansions, the construction of the standard set of normalized spherical harmonics, Y_lm - together with their rotational properties-, and recursion relations. We provide new proofs for Maxwell's theorem, the addition theorem and Hobson's theorem, respectively, using in the latter some elementary notions of the symbolic techniques proper of the theory of invariants. Also, we give an approach based on compact vector methods to express the ...

2008-01-01

169

Modeling, numerical simulation and experimental verification of the unsteady cooling of a solid body in quiescent ambient air  

Energy Technology Data Exchange (ETDEWEB)

The scope of the present article is two-fold. Firstly, to conduct an experiment to provide the temperature-time history of the cooling of a hot ball bearing in quiescent ambient air. Secondly, to predict the temporal variation of the bearing under the hypothesis of natural convection, radiation or natural convection coexists with radiation for a non-vanishing total hemispherical emissivity of the surface of the bearing. Numerical solutions of the three governing nonlinear lumped heat equations were carried out with a Runge-Kutta-Fehlberg (RKF45) algorithm accounting for automatic step size control. The experimental data was obtained with chrome steel ball bearings of diameter 0.953 cm (7/16 in) heated in an electric oven to a pre-set temperature. The heated bearing was exposed later to ambient air at atmospheric temperature and pressure. (orig.)

2004-07-01

170

Linearized augmented-plane-wave method for quasi-unidimensional systems: Carbyne and nanotube (Sc@C{sub 20})  

Energy Technology Data Exchange (ETDEWEB)

The advent of carbon nanotubes, which are graphite layers convoluted in cylinders several nanometers in diameter and several micrometers in length, as well as the experiments on implanting metal atoms in such tubes open the way to producing nanoconductors and other materials with unique properties. For theorists, the basic challenge is interpreting and predicting the structure and properties of these systems. The linearized augmented-plane-wave method (LAPW) is one of the most accurate methods in the theory of the electronic structure of solids. A generalization of this method for quasi-two-dimensional systems, surface electronic states, and layered crystals is known. The LAPW theory for quasi-unidimensional systems, which exhibit translational symmetry in one direction, has been absent thus far. In this paper, the authors suggest a version of such a theory and use this method to calculate the electronic structure of carbyne (a linear chain of ...

1995-10-01

171

Interface heat transfer of horizontal co-current liquid-liquid stratified flow  

International Nuclear Information System (INIS)

Co-current stratified flow of liquid metal and water was investigated in a horizontal rectangular channel. Position of the interface pressure drop and direct contact heat transfer between these immisci ble liquids were measured in a fully developed flow. A turbulence model was proposed to explain the experimental results considering that the turbulence is damped near the liquid-liquid interface by surface tension. The analytical results showed good agreement with the experimental ones. Main results are that (1) position of the interface mainly depends on the flow rate ratio of both liquids, that (2) the pressure drop is approximately proportional to square of the average velocity of water, and that (3) heat transfer rate at direct contact interface is several times higher than that of co-current flow separated by a thin solid plate. (author).

1980-01-01

172

Influence of Pressurisation on SOFC Performance and Durability: ATheoretical Study  

British Library Electronic Table of Contents (United Kingdom)

Abstract Hybrid power plants consisting of a solid oxide fuel cell (SOFC) and a gas turbine show high electrical efficiencies, however require pressurisation of the SOFC to several bar. This paper presents a theoretical investigation of the pressure influence on SOFC performance and durability. A two-dimensional elementary kinetic model is used to predict the performance of a single cell in the pressure range of 1-20-bar. The influence of pressure on thermodynamics, reaction kinetics, porous electrode diffusion, channel transport and efficiency is assessed. It was found that polarisation resistance decreases with increasing pressure due to increased diffusion through porous electrodes and a higher electrode surface coverage with reactant species. Furthermore, open-circuit voltage increases...

2011-01-01

173

Impact of Hight Velocity Cold Spray Particles  

Energy Technology Data Exchange (ETDEWEB)

This paper presents experimental data and an computational model of the cold spray solid particle impact process. Copper particles impacting onto a polished stainless steel substrate are examined. The high velocity impact causes significant plastic deformation of both the particle and the sub- strate, but no melting is observed. The plastic deformation exposes clean surfaces that, under the high impact pressures, result in significant bond strengths between the particle and substrate. Experimental measurements of the splat and crater sizes compare well with the numerical calculations. It is shown that the crater depth is significant and increases with impact velocity. However, the splat diameter is much less sensitive to the impact velocity. It is also shown that the geometric lengths of the splat and crater scale linearly with the diameter of the impacting particle. It is hoped that the results presented will allow better understanding of the ...

1998-12-01

174

Functionalized magnetic nanoparticle with poly(3-thiopheneacetic acid) and its application for electrogenerated chemiluminescence sensor  

British Library Electronic Table of Contents (United Kingdom)

Polymer-coated magnetic nanoparticles (MNPs) have been prepared and used as an immobilization matrix for the fabrication of solid-state tris(2,2prime-bipyridyl)ruthenium(II) (Ru(bpy)32+) electrogenerated chemiluminescence (ECL) sensor. The pre-synthesized maghemite (g-Fe2O3) MNPs were coated with poly(3-thiopheneacetic acid) based on an oxidative polymerization method using KMnO4. The poly(3-thiopheneacetic acid)-coated MNPs have formed the clusters with average diameter of 200-500nm. The multilayer films of poly(3-thiopheneacetic acid)-coated MNPs were uniformly formed on the surface of a Pt electrode by an external magnet. The Ru(bpy)32+ was rapidly incorporated into the multilayer films within 5min through the electrostatic interaction between the Ru(bpy)32+ and the negatively charged c...

2009-01-01

175

Fatigue and creep-fatigue testing of steam filled tubular Alloy 800 specimens  

Energy Technology Data Exchange (ETDEWEB)

A test program was conducted under contract to Sandia National Laboratories to investigate water/steam effects on elevated temperature low cycle fatigue and creep-fatigue of Alloy 800. This report presents interpretation and analysis of the test results. Tubular specimens with water sealed inside were cycled to failure under strain control. Tests were conducted to 616K (650/sup 0/F) and 922K (1200/sup 0/F); some at 922K included tensile or compressive hold periods to simulate creep-fatigue conditions. The tubular specimens showed significantly lower lives than solid bar specimens cycled at equivalent strain ranges. Rough internal surfaces contributed to early crack initiation with these specimens. Inclusion of hold periods caused further large reductions in cycles to failure.

1982-05-01

176

Electron detachment cross-sections and secondary-electron emission factors for heavy-negative-ion beams  

Energy Technology Data Exchange (ETDEWEB)

The properties of negative-ion beams are very important for designing negative-ion apparatus and applications of negative-ion beams, especially, electron detachment cross-sections at the interaction between negative-ion beams and gas particles in the transport system, and secondary-electron emission factors when negative ions are incident on solid surfaces. These properties of negative-ion beams were investigated experimentally as a function of the ion energy under 50 keV. The single electron detachment cross-sections are almost constant in the other of 10[sup -15] cm[sup 2] in this energy range, but double electron detachment cross-sections increase in proportion to the ion velocity and much smaller than the single one. As for the secondary-electron emission factor, the emission factors for negative-ion beam are found to be larger by 1 than those for positive-ion beams. (author).

1994-01-01

177

Electron detachment cross-sections and secondary-electron emission factors for heavy-negative-ion beams  

International Nuclear Information System (INIS)

The properties of negative-ion beams are very important for designing negative-ion apparatus and applications of negative-ion beams, especially, electron detachment cross-sections at the interaction between negative-ion beams and gas particles in the transport system, and secondary-electron emission factors when negative ions are incident on solid surfaces. These properties of negative-ion beams were investigated experimentally as a function of the ion energy under 50 keV. The single electron detachment cross-sections are almost constant in the other of 10"-"1"5 cm"2 in this energy range, but double electron detachment cross-sections increase in proportion to the ion velocity and much smaller than the single one. As for the secondary-electron emission factor, the emission factors for negative-ion beam are found to be larger by 1 than those for positive-ion beams. (author).

1994-01-01

178

Electrochemical behaviour of multicomponent Zr-Ti-V-Mn-Cr-Ni alloys in alkaline solution  

Energy Technology Data Exchange (ETDEWEB)

The effect of the composition of multicomponent Zr-Ti-V-Mn-Cr-Ni alloys on their hydrogen-storage capacity and on the rate of electrosorption/desorption hydrogen was investigated under potentiodynamics as well as single-pulse and long-term galvanostatic conditions. The main characteristics of alloys and alloy electrodes were determined by their structural analysis by means of X-ray diffraction and scanning electron microscope, by specific surface area test and by determination of the hydrogen absorption/desorption isotherms in the gas/solid phase system. It was found that only the alloys with a manganese content below a threshold could be used as electrode materials for Ni-MH batteries, whereas the modification of the electrode material by micro-encapsulation of alloy particles should limit the dissolution of manganese from the electrode material in a strong alkaline solution. (orig.)

1996-01-01

179

Boron diffusion in amorphous silicon  

Energy Technology Data Exchange (ETDEWEB)

We have investigated B diffusion in pre-amorphized silicon. In our experiments, the crystalline surface layer of silicon-on-insulator (SOI) substrates was completely amorphized by Ge ion implantation. Using SOI substrates in this fashion suppressed solid-phase-epitaxy regrowth, making it possible to investigate B diffusion in pre-amorphous silicon over a wider range of temperatures (500-650 deg. C) and times (5-1000 s) than has previously been reported. Diffusivities were determined with the aid of computational processes modeling. The results from this work demonstrate the B diffusion in a-Si is concentration dependent, exhibits a transient enhanced diffusion, and possesses an Arhennius behavior with activation energy of {approx}2.1 eV.

2005-12-05

180

Boron diffusion in amorphous silicon  

International Nuclear Information System (INIS)

We have investigated B diffusion in pre-amorphized silicon. In our experiments, the crystalline surface layer of silicon-on-insulator (SOI) substrates was completely amorphized by Ge ion implantation. Using SOI substrates in this fashion suppressed solid-phase-epitaxy regrowth, making it possible to investigate B diffusion in pre-amorphous silicon over a wider range of temperatures (500-650 deg. C) and times (5-1000 s) than has previously been reported. Diffusivities were determined with the aid of computational processes modeling. The results from this work demonstrate the B diffusion in a-Si is concentration dependent, exhibits a transient enhanced diffusion, and possesses an Arhennius behavior with activation energy of #approx#2.1 eV.

2005-12-05

181

Augmented-plane-wave calculations on small molecules  

International Nuclear Information System (INIS)

We have performed ab initio calculations on a wide range of small molecules, demonstrating the accuracy and flexibility of an alternative method for calculating the electronic structure of molecules, solids, and surfaces. It is based on the local-density approximation (LDA) for exchange and correlation and the nonlinear augmented-plane-wave method. Very accurate atomic forces are obtained directly. This allows for implementation of Car-Parrinello-like techniques to determine simultaneously the self-consistent electron wave functions and the equilibrium atomic positions within an iterative scheme. We find excellent agreement with the best existing LDA-based calculations and remarkable agreement with experiment for the equilibrium geometries, vibrational frequencies, and dipole moments of a wide variety of molecules, including strongly bound homopolar and polar molecules, hydrogen-bound and electron-deficient molecules, and weakly bound alkali ...

182

5. Sampling  

International Nuclear Information System (INIS)

The sampling is described for radionuclide X-ray fluorescence analysis. Aerosols are captured with various filter materials whose properties are summed up in the table. Fine dispersed solid and liquid particles and gaseous admixtures may be captured by bubbling air through a suitable absorption solution. The concentration of small amounts of impurities from large volumes of air is done by adsorbing impurities on surfactants, e.g., activated charcoal, silica gel, etc. Aerosols may be captured using an electrostatic precipitator and aerosol fractions may be separated with a cascade impactor. Water sampling differs by the water source, i.e., ground water, surface water, rain or waste water. Soil samples are taken by probes. (ES).

1983-12-01

183

Task Statement - NEPP - NASA  

Science.gov (United States)

Commercial introduction of new polymer materials for use as the electrolyte in solid tantalum and solid aluminum electrolytic capacitors is underway. ...

184

Control of Effluent Gases from Solid Waste Processing Using Carbon Nanotubes  

Science.gov (United States)

One of the major problems associated with solid waste processing technologies is the release of

2005-01-01

185

Structural Investigations of Silica Polyamine Composites: Surface Coverage, Metal Ion Coordination, and Ligand Modification  

Science.gov (United States)

Silanization of the silica gel surface in the synthesis of silica gel polyamine composites uses (chloropropyl)-trichlorosilane (CPTCS). It is possible to substitute a molar fraction of reagent CPTCS with methyltrichlorosilane (MTCS), creating a mixed silane surface layer. Two types of silica gels were modified with a series of MTCS:CPTCS molar ratios. Solid-state CP/MAS 29Si and 13C NMR spectroscopies were used to evaluate the surface silane composition. Surface silane coverage was markedly improved for the resulting gels. When polyamines were grafted to the resultant MTCS:CPTCS silane layers, it was shown that the decrease in the number of propyl attachments to the polyamine resulted in increased quantities of ''free amines''. Optimum MTCS:CPTCS ratios were determined for three polyamines grafted onto one silica gel. A substantial free amine ...

2006-09-13

186

Structural Investigations of Silica Polyamine Composites: Surface Coverage, Metal Ion Coordination, and Ligand Modification  

Energy Technology Data Exchange (ETDEWEB)

Silanization of the silica gel surface in the synthesis of silica gel polyamine composites uses (chloropropyl)-trichlorosilane (CPTCS). It is possible to substitute a molar fraction of reagent CPTCS with methyltrichlorosilane (MTCS), creating a mixed silane surface layer. Two types of silica gels were modified with a series of MTCS:CPTCS molar ratios. Solid-state CP/MAS 29Si and 13C NMR spectroscopies were used to evaluate the surface silane composition. Surface silane coverage was markedly improved for the resulting gels. When polyamines were grafted to the resultant MTCS:CPTCS silane layers, it was shown that the decrease in the number of propyl attachments to the polyamine resulted in increased quantities of ''free amines''. Optimum MTCS:CPTCS ratios were determined for three polyamines grafted onto one silica gel. A substantial free amine ...

2006-09-13

187

Modeling of the non isothermal and non isobaric transformations kinetics. Application to the kaolinite de-hydroxylation and to the tri-uranium octo-oxide reduction by hydrogen; Modelisation de la cinetique de transformations non isothermes et (ou) non isobares. Application a la deshydroxylation de la kaolinite et a la reduction de l'octooxyde de triuranium par l'hydrogene  

Energy Technology Data Exchange (ETDEWEB)

The aim of this work is to be able to describe transformations, occurring when solids and gases are in non isothermal and non isobaric conditions, with kinetic models. A methodology has been used. Two essential processes have to be taken into account: the germination and the growth. The germs are supposed to be formed (at constant temperature and pressure) in the grains surface with a constant velocity by surface unit, (gamma), called germination surface frequency (number of germs.m{sup -2}.s{sup -1}. The growth velocity is characterized by a growth surface reactivity, (phi) (in mol.m{sup -2}.s{sup -1}). With an appropriate transformation model, it is possible to obtain the variations of (gamma) and (phi) in terms of the temperature and pressure which are then used in the calculation of the velocity in non isothermal and non isobaric conditions. In order to validate the developed ...

2002-12-15

188

Report from the third workshop on future directions of solid-state chemistry: The status of solid-state chemistry and its impact in the physical sciences  

British Library Electronic Table of Contents (United Kingdom)

Executive summaryForewordPublic awareness of solid-state chemistry, or more broadly solid-state science and technology rapidly grew along with the transistor revolution and the development of the integrated circuit. We are now at the half-way point in the solid state century [Scientific American The Solid-State Century 1997;8(1) [special issue

2008-01-01

189

Transient enhanced diffusion in ion-implanted silicon  

Energy Technology Data Exchange (ETDEWEB)

We discuss the transient-enhanced diffusion of Sb, As, P, In, Ga, and B in ion-implanted Si, where the near-surface region has been amorphized by the dopant or by a self-implantation process. With Sb, a large transient diffusion enhancement is observed proportional to dopant concentration. For Sb, As, P, and In, the enhancement follows the relative interstitialcy diffusion coefficient. We believe this behavior is caused by stable implantation-induced point defects present in the amorphous surface layer, which decay during thermal processing to release high concentrations of self-interstitials. This process occurs in competition with the solid phase epitaxial (SPE) growth process, and for high dopant concentrations can occur in the amorphous phase ahead of the crystallization front. We believe this may be the origin of the dopant redistribution which can occur during SPE growth, which sets the upper limit to the dopant ...

1987-03-01

190

Structural transformations in Sc/Si multilayers irradiated by EUVlasers  

Energy Technology Data Exchange (ETDEWEB)

Multilayer mirrors for the extreme ultraviolet (EUV) are keyelements for numerous applications of coherent EUV sources such as newtabletop lasers and free-electron lasers. However the field ofapplications is limited by the radiation and thermal stability of themultilayers. Taking into account the growing power of EUV sources thestability of the optics becomes crucial. To overcome this problem it isnecessary to study the degradation of multilayers and try to increasetheir temporal and thermal stability. In this paper we report the resultsof detailed study of structural changes in Sc/Simultilayers when exposedto intense EUV laser pulses. Various types of surface damage such asmelting, boiling, shockwave creation and ablation were observed asirradiation fluencies increase. Cross-sectional TEM study revealed thatthe layer structure was completely destroyed in the upper part ofmultilayer, but still survived below. The layers adjacent tothe substrateremained intact even ...

2007-08-21

191

Preparation, characterization and electrical properties of SnO{sub 2} based liquid petroleum gas sensor  

Energy Technology Data Exchange (ETDEWEB)

The present investigation deals with the fabrication of liquid petroleum gas (LPG) sensor based on semiconducting oxide SnO{sub 2}. The gas sensor elements have been prepared by conventional solid state route. Addition of noble metal sensitizer, palladium and grain growth inhibitor, aluminum silicate to the base material SnO{sub 2}, not only improved the sensitivity towards LPG but also the selectivity in the presence of CO and CH{sub 4} gases. Out of various sensor compositions, SnO{sub 2}:Al{sub 2}Si{sub 2}O{sub 7} (35 wt.%):Pd (1.5 wt.%) sintered at 800 C for 5 h has shown high sensitivity (0.97) towards LPG at an operating temperature of 350 C. Different characterization techniques have been employed, such as differential thermal analysis (DTA), surface area analyzer, X-ray diffraction (XRD), to study the formation of SnO{sub 2}, surface area and crystallite size, respectively. The results suggested the possibility of ...

1999-03-25

192

Neural net formulations for organically modified, hydrophobic silica aerogel  

Energy Technology Data Exchange (ETDEWEB)

Organic modification of aerogel chemical formulations is known to transfer desirable hydrophobicity to lightweight solids. However, the effects of chemical modification on other material constants such as elasticity, compliance, and sound dampening present a difficult optimization problem. Here a statistical treatment of a 9-variable optimization is accomplished with multiple regression and an artificial neural network (ANN). The ANN shows 95 percent prediction success for the entire data set of elasticity, compared to a multidimensional linear regression which shows a maximum correlation coefficient, R=0.782. In this case, using the Number of Categories Criterion for the standard multiple regression, traditional statistical methods can distinguish fewer than 1.83 categories (high and low elasticity) and cannot group or cluster the data to give more refined partitions. A non-linear surface requires at least 3 categories (high, low, and medium ...

1997-07-01

193

Mechanisms controlling the leaching kinetics of fixated flue gas desulfurization (FGD) material under neutral and acidic conditions.  

Science.gov (United States)

A number of agricultural and engineering uses for fixated flue gas desulfurization (FGD) material exist; however, the potential for leaching of hazardous elements has limited widespread application and the processes controlling the leaching of this material are poorly understood. In this study, a flow-through rotating-disk system was applied to elucidate the relative importance of bulk diffusion, pore diffusion, and surface chemical reaction in controlling the leaching of fixated FGD material under pH conditions ranging from 2.2 to 6.8. Changing the hydrodynamics in the rotating disk system did not affect the leaching kinetics at both pH 2.2 and 6.8, indicating that bulk diffusion was not the kinetic-limiting step. Application of the shrinking core model (SCM) to the data suggested a surface reaction-controlled mechanism, rather than a pore diffusion mechanism. The leaching of fixated FGD material increased with decreasing pH, suggesting it can ...

2007-05-07

194

Evaluation of the increase of superficial dose due to thermoplastic immobilizing in radiotherapy; Avaliacao dos efeitos de superficializacao de dose por imobilizadores termoplasticos em radioterapia  

Energy Technology Data Exchange (ETDEWEB)

Perforated thermoplastic masks are used to provide patients immobilization. This procedure inserts a material in the path of the radiation beam, that attenuates and modifies the beam fluence and flatness. The present study evaluates the increase in skin dose as a result of using thermoplastic masks. Relative doses were measured on the surface of a solid water phantom, in the presence and absence of masks. These masks were stretched according to deformation patterns observed in clinical routine. The measurements were obtained with a plane-parallel chamber (Markus type 23343) and radiochromic film (EBT Gafchromic) for 6MV X-rays from a linear accelerator, and for a radiation beam from a cobalt therapy unit. The results showed that thermoplastic masks, whose thickness varied between 2 and 3 mm, increased the dose on the surface by a factor of 3. Due to the variations in the skin dose distribution, clinical procedures were ...

2010-07-01

195

Evaluation of the increase of superficial dose due to thermoplastic immobilizing in radiotherapy  

International Nuclear Information System (INIS)

Perforated thermoplastic masks are used to provide patients immobilization. This procedure inserts a material in the path of the radiation beam, that attenuates and modifies the beam fluence and flatness. The present study evaluates the increase in skin dose as a result of using thermoplastic masks. Relative doses were measured on the surface of a solid water phantom, in the presence and absence of masks. These masks were stretched according to deformation patterns observed in clinical routine. The measurements were obtained with a plane-parallel chamber (Markus type 23343) and radiochromic film (EBT Gafchromic) for 6MV X-rays from a linear accelerator, and for a radiation beam from a cobalt therapy unit. The results showed that thermoplastic masks, whose thickness varied between 2 and 3 mm, increased the dose on the surface by a factor of 3. Due to the variations in the skin dose distribution, clinical procedures were ...

2010-08-18

196

Atomic beam spectrometer using a LiF analyzer crystal  

International Nuclear Information System (INIS)

An energy analyzer has been constructed and operated in UHV for the purpose of analyzing the energy of neutral atoms scattered from solid surfaces. The analyzer consists of a LiF single crystal located at an angle close to the normal to the sample crystal so that the diffraction pattern obtained by scanning the LiF crystal yields the energy of the scattered atoms. Two designs which have been used are described. The temperature of both sample and analyzer crystal is near 20 K and once cleaned they can be maintained in the state of initial preparation for many weeks. The sample was a (001) Cu surface in this case. Such an energy analyzer can only be used, in most cases, for He atom scattering although Ne atoms could be used if the scattered intensities were adequate. The detector developed in this study is able to detect about 2 x 10"5 atoms/s. The resolution of the spectrometer depends on the incident energy of the atom and ...

1978-01-01

197

Preparation and characterization of a novel polymeric based solid-solid phase change heat storage material  

International Nuclear Information System (INIS)

Here we reported a two-step procedure for preparing a novel polymeric based solid-solid phase change heat storage material. Firstly, a copolymer monomer containing a polyethylene glycol monomethyl ether (MPEG) phase change unit and a vinyl unit was synthesized via the modification of hydrogen group of MPEG. Secondly, by copolymerization of the copolymer monomer and phenyl ethylene, a novel polymeric based solid-solid phase change heat storage material was prepared. The composition, structure and properties of the novel polymeric based solid-solid phase change material were characterized by IR, "1H NMR, DSC, WAXD, and POM, respectively. The results show that the novel polymeric based solid-solid phase change material possesses of excellent crystal properties and high phase change enthalpy.

2009-06-01

198

Solid state alloying by plasma nitriding and diffusion annealing treatment for austenitic stainless steel  

Energy Technology Data Exchange (ETDEWEB)

Nitrogen has been added to stainless steels to improve mechanical strength and corrosion resistance. High nitrogen steel production is limited by high gas pressure requirements and low nitrogen solubility in the melt. One way to overcome this limitation is the addition of nitrogen in solid state because of its higher solubility in austenite. However, gas and salt bath nitriding have been done at temperatures around 550 C, where nitrogen solubility in the steel is still very low. High temperature nitriding has been, thus proposed to increase nitrogen contents in the steel but the presence of oxide layers on top of the steel is a barrier to nitrogen intake. In this paper a modified plasma nitriding process is proposed. The first step of this process is a hydrogen plasma sputtering for oxide removal, exposing active steel surface improving nitrogen pickup. This is followed by a nitriding step where high nitrogen contents are introduced in the ...

1999-07-01

199

Solid state alloying by plasma nitriding and diffusion annealing treatment for austenitic stainless steel  

International Nuclear Information System (INIS)

Nitrogen has been added to stainless steels to improve mechanical strength and corrosion resistance. High nitrogen steel production is limited by high gas pressure requirements and low nitrogen solubility in the melt. One way to overcome this limitation is the addition of nitrogen in solid state because of its higher solubility in austenite. However, gas and salt bath nitriding have been done at temperatures around 550 C, where nitrogen solubility in the steel is still very low. High temperature nitriding has been, thus proposed to increase nitrogen contents in the steel but the presence of oxide layers on top of the steel is a barrier to nitrogen intake. In this paper a modified plasma nitriding process is proposed. The first step of this process is a hydrogen plasma sputtering for oxide removal, exposing active steel surface improving nitrogen pickup. This is followed by a nitriding step where high nitrogen contents are introduced in the ...

1998-05-24

200

On the influence of microstructure and carbide content of steels on the electrochemical dissolution process in aqueous NaCl-electrolytes  

Energy Technology Data Exchange (ETDEWEB)

The electrochemical dissolution behaviour of armco-iron and of the steels C15, C45, C60 and 100Cr6 in concentrated sodium chloride media has been investigated. Anodic metal dissolution experiments have been carried out using the flow channel cell (parallel plate reactor), the rotating cylinder electrode (RCE) and the capillary cell. The microstructure of the steel has been varied through variation of carbon content and heat treatment (e.g. soft annealed with globular carbides or pearlitic). Current-efficiency values have been obtained by gravimetric measurements in the current-density range from i=5 to 60 A/cm{sup 2}. For the soft annealed steels, the divalent ferrite dissolution in combination with electroless cementite removal dominates. For the pearlitic steels, the occurrence of oxygen evolution electronically conductive metal carbides or trivalent ferrite dissolution, depending on the current density applied, was detected. Microstructure dependent potentiostatic current transients ...

2002-10-01

201

Characterization of a time-of-flight mass spectrometer and its applications in the study of solid surfaces; Charakterisierung eines Flugzeitmassenspektrometers und seine Anwendungen in der Festkoerperoberflaechenuntersuchung  

Energy Technology Data Exchange (ETDEWEB)

The object and the purpose of the present work was to develop, to assemble and to start running a new TOF (time of flight) mass spectrometer for imaging SNMS analytic which is optimized for the analysis of highly molecular secondary ions. The most important purpose was the characterization of the TOF mass spectrometer. The obtained mass spectra of indium, tantalum and silver clusters reflect the excellent properties of the TOF mass spectrometer for the detection of large clusters with good detection efficiency up to masses of 16000 amu. The possibility of the deflection of selected saturated atom and cluster peaks serves for further improvement of the detection efficiency for large molecules. The accessible mass resolution was determined to be of the order of m/{delta}m=1000 in the high mass region. Numerous measurements were carried out to characterize the useful yield of this spectrometer. For a best possible adaptation of the TOF mass spectrometer for the detection of highly ...

2006-12-21

202

Characterization of VPO ammoxidation catalysts by in situ methods  

Energy Technology Data Exchange (ETDEWEB)

In-situ methods are well known as powerful tools in studying catalyst formation processes, their solid state properties under working conditions and the interaction with the feed, intermediates and products to reveal reaction mechanisms. This paper gives a short overview on results of intense studies using in-situ techniques to reveal VPO catalyst generation processes, interaction of educts, intermediates and products with VPO catalyst surfaces and mechanistic insights. Catalytic data of the ammoxidation of toluene on different VPOs complete these findings. The precursor-catalyst transformation processes were preferently investigated by in-situ XRD, in-situ Raman and in-situ ESR spectroscopy. The interaction of aromatic molecules and intermediates, resp., and VPO solid surfaces was followed by in-situ ESR and in-situ FTIR spectroscopy. Mechanistic information was mainly obtained using in-situ FTIR ...

1998-12-31

203

Surface Decontamination by Solution  

International Science & Technology Center (ISTC)

Development of Technology for Metal Surface Decontamination in Aqueous Solutions

204

Tritium diffusivity in crystal grain of Li{sub 2}TiO{sub 3} and tritium release behavior under several purge gas conditions  

Energy Technology Data Exchange (ETDEWEB)

It has been reported by the present authors that behavior of tritium release from solid breeder grain is consisted of diffusion in grain, tritium transfer at surface layer and surface reactions on grain surface such as adsorption or isotope exchange reactions. Tritium release curves estimated using the tritium release model gave good agreement with observed tritium release curves from Li{sub 4}SiO{sub 4}, Li{sub 2}ZrO{sub 3} or LiAlO{sub 2}. Tritium release behavior from Li{sub 2}TiO{sub 3} under humid purge gas, dry purge gas and dry purge gas with hydrogen conditions is discussed in this study, tritium release curves using the release model that we proposed previously give a good agreements with experimental tritium release curves. Tritium effective diffusivity in the crystal grain of Li{sub 2}TiO{sub 3} is also estimated in this study using a curve-fitting method applied to the release curves ...

2008-05-15

205

Tritium diffusivity in crystal grain of Li_2TiO_3 and tritium release behavior under several purge gas conditions  

International Nuclear Information System (INIS)

It has been reported by the present authors that behavior of tritium release from solid breeder grain is consisted of diffusion in grain, tritium transfer at surface layer and surface reactions on grain surface such as adsorption or isotope exchange reactions. Tritium release curves estimated using the tritium release model gave good agreement with observed tritium release curves from Li_4SiO_4, Li_2ZrO_3 or LiAlO_2. Tritium release behavior from Li_2TiO_3 under humid purge gas, dry purge gas and dry purge gas with hydrogen conditions is discussed in this study, tritium release curves using the release model that we proposed previously give a good agreements with experimental tritium release curves. Tritium effective diffusivity in the crystal grain of Li_2TiO_3 is also estimated in this study using a curve-fitting method applied to the release curves obtained under the humid purge gas condition. It is ...

2008-05-01

206

Electron-beam induced RAFT-graft polymerization of poly(acrylic acid) onto PVDF  

Energy Technology Data Exchange (ETDEWEB)

This paper explores for the first time the post-radiation-induced-graft polymerization on solid substrate using reversible addition-fragmentation transfer (RAFT) mechanism. Radiation-induced graft polymerization onto polymers is a potentially interesting technique to create easily new materials from highly resistant polymers, e.g. surface graft polymerization of acrylic acid (AA) onto poly(vinylidene difluoride) (PVDF) improves its surface properties without losing its excellent mechanical properties. As a consequence of the radical nature of the polymerization processes it is difficult to control molecular weight of grafted chains, and therefore design and standardize the properties of the final product. RAFT polymerization is a suitable method to obtain monodisperse polymers. The ability of the RAFT agents to control the polymer chain length could be an interesting approach to improve the grafted polymers obtained by ...

2005-07-01

207

Isochron measurements of naturally irradiated K-feldspar grains  

International Nuclear Information System (INIS)

The equivalent doses of K-feldspar grains in a range of grain sizes from 90 to 250#mu#m diameter were measured using a single-aliquot regenerative-dose protocol for the infrared stimulated luminescence (IRSL) signals for two samples of desert sand. The equivalent doses for each sample were compared with that for the 125-150#mu#m grains of quartz from the same samples. The results suggested that the K-feldspar equivalent doses were underestimated because of anomalous fading. Measurements of the decay of the IRSL signals following laboratory irradiation for these two samples, and an additional one from a previously published isochron study, showed anomalous fading during the period of laboratory storage. The decay rate was about 3% per decade for all samples and was independent of the grain size used. Using plots of equivalent doses for K-feldspars as a function of their calculated internal dose rate, and the quartz equivalent dose as a function ...

2007-09-01

208

Vitrification of waste  

Energy Technology Data Exchange (ETDEWEB)

A method for encapsulating and immobilizing waste for disposal. Waste, preferably, biologically, chemically and radioactively hazardous, and especially electronic wastes, such as circuit boards, are placed in a crucible and heated by microwaves to a temperature in the range of approximately 300{degrees}C to 800{degrees}C to incinerate organic materials, then heated further to a temperature in the range of approximately 1100{degrees}C to 1400{degrees}C at which temperature glass formers present in the waste will cause it to vitrify. Glass formers, such as borosilicate glass, quartz or fiberglass can be added at the start of the process to increase the silicate concentration sufficiently for vitrification.

1992-12-31

209

RBS Characterization of Yttrium Iron Garnet Thin Films  

International Nuclear Information System (INIS)

Magnetic materials such as yttrium iron garnet (YIG) are of great importance for its magneto-optic properties and for their potential applications in the domain of optical telecommunications. The deposition of thin films of YIG, on quartz or GGG (gadolinium gallium garnet) substrate, was performed using radio frequency non reactive magnetron sputtering, followed by high temperature annealing which is needed to enhance the crystallinity of the layers. Rutherford backscattering spectrometry RBS was used to determine the thickness and stoichiometry of the performed layers in order to investigate correlations between growth conditions and the quality of the final material. RBS measurements showed the influence of the deposition time and the temperature substrate on the film growth and its stoichiometry. (author)

2008-12-13

210

Discussions of the uranium geology working groups IGC, Sydney  

International Nuclear Information System (INIS)

The report is divided into six working group discussions on the following subjects: 1) Chemical and physical mechanisms in the formation of uranium mineralization, geochronology, isotope geology and mineralogy; 2) Sedimentary basins and sandstone-type uranium deposits; 3) Uranium in quartz-pebble conglomerates; 4) Vein and similar type deposits (pitchblende); 5) Other uranium deposits; 6) Relation of metallogenic, tectonic and zoning factors to the origin of uranium deposits. Each working group paper contains a short introductory part followed by a discussion by the working group members.

1978-01-01

211

Characterization of Metal Oxide and Silica-Based Electrodes  

Energy Technology Data Exchange (ETDEWEB)

Objective of the project is characterization of electrode reactions in molten salt by using metal oxides and silica-based electrode. The scope of project are characterization of metal oxide properties in molten salt and miniaturization of 3-electrode electrochemical test cell. Electrochemical micro-cell for actinide-LiCl-KCl molten salt was newly designed. Electroless and electrochemical deposition technique was applied to Mo coating on quartz tube. From the design of electrode and 3-electrode electrochemical cell suitable for the tests in molten salt electrolyte, so it is anticipated to get the information on the electrochemical behavior of metallic electrode in molten salt and to secure the information on oxidation/reduction behavior of actinide

2010-05-15

212

BUBL LINK Catalogue of Internet Resources  

Wastenet

...O | P | Q | R | S | T | U | V | W | X | Y | Z 230 Christianity: general resources ...com: Christianity: General Anno Domini: Jesus Through the Centuries Bible and Homosexuality Christian Theological Research Fellowship Papers Christianity Links and Resources Directory ...Good Digital Collections Lambert's Web Links MUNDUS New Testament Gateway Omnilist of Christian Starting Points Quartz Hill School of Theology Web Library Theology Online ...com: Christianity: General Offers original articles and features about Christianity in general plus annotated links to selected relevant Internet resources, compiled by ...

213

The weak force and SETH: The search for Extra-Terrestrial Homochirality  

Energy Technology Data Exchange (ETDEWEB)

We propose that a search for extra-terrestrial life can be approached as a Search for Extra-Terrestrial Homochirality{emdash}SETH. Homochirality is probably a pre-condition for life, so a chiral influence may be required to get life started. We explain how the weak force mediated by the {ital Z}{sup 0} boson gives rise to a small parity-violating energy difference (PVED) between enantiomers, and discuss how the resulting small excess of the more stable enantiomer may be amplified to homochirality. Titan and comets are good places to test for emerging pre-biotic homochirality, while on Mars there may be traces of homochirality as a relic of extinct life. Our calculations of the PVED show that the natural L-amino acids are indeed more stable than their enantiomers, as are several key D-sugars and right-hand helical DNA. Thiosubstituted DNA analogues show particularly large PVEDs. L-quartz is also more stable than D-quartz, and we believe that ...

1996-07-01

214

A Spindle Cell Predominant Pancreatic Solid-pseudopapillary Tumor  

UK PubMed Central (United Kingdom)

A hitherto unrecognized variant of solid-pseudopapillary tumor (SPT) of the pancreas is reported. The tumor presented in the pancreatic tail of a 44-year-old female patient. It was a well-defined, solid...Full Text Available

2008-08-30

215

40 CFR 261.2 - Definition of solid waste.  

Science.gov (United States)

...2009-07-01 false Definition of solid waste. 261.2 Section 261.2 Protection...PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) IDENTIFICATION AND LISTING OF HAZARDOUS WASTE General § 261.2 Definition...

2009-07-01

216

Improved hydrogen sorption kinetics in wet ball milled Mg hydrides  

Energy Technology Data Exchange (ETDEWEB)

In this work, wet ball milling method is used in order to improve hydrogen sorption behaviour due to its improved microstructure of solid hydrogen materials. Compared to traditional ball milling method, wet ball milling has benefits on improvement of MgH{sub 2} microstructure and further influences on its hydrogen sorption behavior. With the help of solvent tetrahydrofuran (THF), wet ball milled MgH{sub 2} powder has much smaller particle size and its specific surface area is 7 times as large as that of dry ball milled MgH{sub 2} powder. Although after ball milling the grain size is decreased a lot compared to as-received MgH{sub 2} powder, the grain size of wet ball milled MgH{sub 2} powder is larger than that of dry ball milled MgH{sub 2} powder due to the lubricant effect of solvent THF during wet ball milling. The improved particle size and specific surface area of wet ball milled MgH{sub 2} powder is found to be ...

2011-05-04

217

Review of Constructed Subsurface Flow vs. Surface Flow Wetlands  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this document is to use existing documentation to review the effectiveness of subsurface flow and surface flow constructed wetlands in treating wastewater and to demonstrate the viability of treating effluent from Savannah River Site outfalls H-02 and H-04 with a subsurface flow constructed wetland to lower copper, lead and zinc concentrations to within National Pollutant Discharge Elimination System (NPDES) Permit limits. Constructed treatment wetlands are engineered systems that have been designed and constructed to use the natural functions of wetlands for wastewater treatment. Constructed wetlands have significantly lower total lifetime costs and often lower capital costs than conventional treatment systems. The two main types of constructed wetlands are surface flow and subsurface flow. In surface flow constructed wetlands, water flows above ground. Subsurface flow constructed wetlands are designed to ...

2004-09-01

218

Study of radiation chemistry in solids using solid hydrogen  

Energy Technology Data Exchange (ETDEWEB)

Having simple and highly symmetric structure, solid hydrogen is a useful matrix on the study of radiation-chemical processes in solid phase which have been less understood in previous studies. We have found three outstanding findings: resonance effects on the tunneling reaction H+H{sub 2} {yields} H{sub 2} + H, effects of pressure on the dissociation and recombination of H{sub 2} molecules in solid hydrogen, and high-resolution ESR spectroscopy using a solid parahydrogen matrix. (author)

2002-03-01

219

Passivity behavior of melt-spun Mg-Y Alloys  

Energy Technology Data Exchange (ETDEWEB)

Several Mg-Y binary ribbons with Y content up to {approx}17.9 at.% were fabricated by melt-spinning. X-ray diffraction (XRD) revealed that the phase structure changes with increasing Y content from extended solid solution to partially amorphous, and then fully intermetallic Mg{sub 24}Y{sub 5}. Anodic potentiodynamic polarization performed in 0.01 M NaCl electrolyte (pH=12) revealed improved anodic passivity behavior compared to pure Mg for all the Mg-Y alloys. X-ray photoelectron spectroscopy (XPS) revealed that the improved passivity of Mg-Y was more related to the elemental oxidation state rather than the concentration of the surface components. To study the effect of Cl{sup -} ion on the passivity behavior, anodic potentiodynamic and potentiostatic polarization were performed on Mg-17.9 at.% Y in alkaline (pH=12) NaCl electrolytes containing Cl{sup -} ion in the concentration range from 0.00 to 0.50 M. The passive films formed in 0.01 M NaCl ...

2003-12-15

220

Passivity behavior of melt-spun Mg-Y Alloys  

International Nuclear Information System (INIS)

Several Mg-Y binary ribbons with Y content up to #approx#17.9 at.% were fabricated by melt-spinning. X-ray diffraction (XRD) revealed that the phase structure changes with increasing Y content from extended solid solution to partially amorphous, and then fully intermetallic Mg_2_4Y_5. Anodic potentiodynamic polarization performed in 0.01 M NaCl electrolyte (pH=12) revealed improved anodic passivity behavior compared to pure Mg for all the Mg-Y alloys. X-ray photoelectron spectroscopy (XPS) revealed that the improved passivity of Mg-Y was more related to the elemental oxidation state rather than the concentration of the surface components. To study the effect of Cl"- ion on the passivity behavior, anodic potentiodynamic and potentiostatic polarization were performed on Mg-17.9 at.% Y in alkaline (pH=12) NaCl electrolytes containing Cl"- ion in the concentration range from 0.00 to 0.50 M. The passive films formed in 0.01 M NaCl electrolyte were ...

2003-12-15

221

Manganite reduction by Shewanella putrefaciens MR-4  

Energy Technology Data Exchange (ETDEWEB)

Previous studies have documented dissimilatory growth of bacteria on solid Mn{sup 4+} oxide, but Mn{sup 3+} oxides have not been previously studied; here the authors have demonstrated for the first time the bacterial reduction of manganite. Strain MR-4 of Shewanella putrefaciens was able to grow on and rapidly reduce insoluble needle-shaped crystals of synthetic manganite (MnOOH), converting them to soluble Mn{sup 2+} in the process. The rate of Mn{sup 3+} reduction was optimal at pH of 7.0 and 26 C consistent with an enzymatic reaction. In addition the rates of reduction were in proportion to the amount of manganite added, but nearly independent of the cell concentration present (e.g., cell number had only a small effect on the rate of Mn{sup 3+} reduction at early stages of growth) suggesting that surface properties were dictating the rates of metal reduction. This thesis was supported by major differences in reduction rates when Mn oxides of ...

1998-11-01

222

Evaluation of 1-site and 5-site models of methane on its adsorption on graphite and in graphitic slit pores.  

Science.gov (United States)

In this paper, we evaluate the performance of the 1- and 5-site models of methane on the description of adsorption on graphite surfaces and in graphitic slit pores. These models have been known to perform well in the description of the fluid-phase behavior and vapor-liquid equilibria. Their performance in adsorption is evaluated in this work for nonporous graphitized thermal carbon black, and simulation results are compared with the experimental data of Avgul and Kiselev (Chemistry and Physics of Carbon; Dekker: New York, 1970; Vol. 6, p 1). On this nonporous surface, it is found that these models perform as well on isotherms at various temperatures as they do on the experimental isosteric heat for adsorption on a graphite surface. They are then tested for their performance in predicting the adsorption isotherms in graphitic slit pores, in which we would like to explore the effect of confinement on the molecule packing. ...

2005-10-20

223

Characterization of lithium electrode surface in lithium secondary batteries by in situ Raman spectroscopic methods. Final report, 1 September 1989-31 December 1992  

Energy Technology Data Exchange (ETDEWEB)

Surface layers on lithium electrodes formed in several solvents including dimethyl carbonate (DMC), diethyl carbonate (DEC), polyethylene glycol 400 dimethyl ether (PEG400DME), and propylene carbonate (PC) have been studied by Raman spectroscopy. Both DMC and DEC were used singly, and also mixed with either methyl acetate or methyl formate. The Raman spectra showed that passive films formed on the Li surface in different solvents may have different chemical structures, which changed during the charging and discharging processes. A solid film of fullerene C6O, which could be used as a cathode in Li rechargeable batteries, was examined in the PEG400DME solution by both electrochemical and Raman spectroscopy. Cyclic voltammograms (CVs) showed five redox peaks which suggested the formation of C6O(-), C6O(2-), C6O(3-), C6O(4-), and C6O(5-). Raman spectra obtained from thin C6O film indicated that the thin fulleride film ...

1993-03-24

224

Study of cytomorphology of solid pseudopapillary tumor of pancreas and its differential diagnosis  

UK PubMed Central (United Kingdom)

Background:Solid pseudopapillary tumor is a rare pancreatic neoplasm with uncertain to low malignant potential. This is an uncommon neoplasm with many pseudonyms, occurring...Full Text Available

2010-10-01

225

Solid serous microcystic adenoma of the pancreas  

UK PubMed Central (United Kingdom)

BackgroundCystic neoplasms of the pancreas are less common than solid tumors, and portend a better prognosis. They can be divided into serous and mucinous subtypes, with the former...Full Text Available

226

Solid Waste & Financial Assistance Program  

Science.gov (United States)

This program deals with solid waste disposal with topics/services covering: Reusable Building Materials and Large Household Items Exchange, Beneficial Use Determination, Biosolids, Certification, Compost Facil...

227

Gasless Combustion of Solid Fuel Mixtures  

International Science & Technology Center (ISTC)

Investigation of the Macrokinetics and Energy of Self-Oscillatory Processes of Gasless Combustion of Solid Fuel Mixtures Proposed for the Design of Short-Term Thermal and Electrical Sources

228

A Theoretical Solid Oxide Fuel Cell Model for - The NASA Glenn ...  

Science.gov (United States)

May 31, 2011 ... A Theoretical Solid Oxide Fuel Cell Model for System Controls and Stability Design AUTHOR(S): Kopasakis, George; Brinson, Thomas; Credle, ...

230

Integrated Models for Solid Waste Management in Tourism Regions: Langkawi Island, Malaysia  

Science.gov (United States)

The population growth, changing consumption patterns, and rapid urbanization contribute significantly to the growing volumes of solid waste that are generated in urban settings. As the rate of urbanization increases, demand on the services of solid waste management increases. The rapid urban growth in Langkawi Island, Malaysia, combined with the increasing rates of solid waste production has provided evidence that the traditional solid waste management practices, particularly the methods of waste collection and disposal, are inefficient and quite nonsustainable. Accordingly, municipal managers and planners in Langkawi need to look for and ...

2011-09-04

231

Unrestricted disposal of minimal activity levels of radioactive wastes: exposure and risk calculations  

Energy Technology Data Exchange (ETDEWEB)

The US Nuclear Regulatory Commission is currently considering revision of rule 10 CFR Part 20, which covers disposal of solid wastes containing minimal radioactivity. In support of these revised rules, we have evaluated the consequences of disposing of four waste streams at four types of disposal areas located in three different geographic regions. Consequences are expressed in terms of human exposures and associated health effects. Each geographic region has its own climate and geology. Example waste streams, waste disposal methods, and geographic regions chosen for this study are clearly specified. Monetary consequences of minimal activity waste disposal are briefly discussed. The PRESTO methodology was used to evaluate radionuclide transport and health effects. This methodology was developed to assess radiological impacts to a static local population for a 1000-year period following disposal. Pathways and processes of transit from the trench to exposed ...

1984-08-01

232

Understanding and controlling transient enhanced dopant diffusion in silicon  

Energy Technology Data Exchange (ETDEWEB)

Implanted B and P dopants in Si exhibit transient enhanced diffusion (TED) during initial annealing which arises from the excess interstitials generated by the implant. In order to study the mechanisms of TED, the authors have used B doping marker layers in Si to probe the injection of interstitials from near-surface, non-amorphizing Si implants during annealing. The in-diffusion of interstitials is limited by trapping at impurities and has an activation energy of {approximately}3.5 eV. Substitutional C is the dominant trapping center with a binding energy of 2--2.5 eV. The high interstitial supersaturation adjacent to the implant damage drives substitutional B into metastable clusters at concentrations below the B solid solubility limit. Transmission electron microscopy shows that the interstitials driving TED are emitted from {l_brace}311{r_brace} defect clusters in the damage region at a rate which also exhibits an activation energy of 3.6 ...

1995-12-31

233

Understanding and controlling transient enhanced dopant diffusion in silicon  

International Nuclear Information System (INIS)

Implanted B and P dopants in Si exhibit transient enhanced diffusion (TED) during initial annealing which arises from the excess interstitials generated by the implant. In order to study the mechanisms of TED, the authors have used B doping marker layers in Si to probe the injection of interstitials from near-surface, non-amorphizing Si implants during annealing. The in-diffusion of interstitials is limited by trapping at impurities and has an activation energy of #approx#3.5 eV. Substitutional C is the dominant trapping center with a binding energy of 2--2.5 eV. The high interstitial supersaturation adjacent to the implant damage drives substitutional B into metastable clusters at concentrations below the B solid solubility limit. Transmission electron microscopy shows that the interstitials driving TED are emitted from #left brace#311#right brace# defect clusters in the damage region at a rate which also exhibits an activation energy of 3.6 ...

234

Tris(2,2prime-bipyridyl)ruthenium(II) Electrogenerated Chemiluminescence Sensor Based on Sol-Gel-Derived V2O5/Nafion Composite Films  

British Library Electronic Table of Contents (United Kingdom)

Mesoporous V2O5/Nafion composite films have been used for the immobilization of tris(2,2prime-bipyridyl)ruthenium (II) (Ru(bpy)$\\rm{ {_{3}^{2+}}}$) on an electrode surface to yield a solid-state electrogenerated chemiluminescence (ECL) sensor. The electrochemical and ECL behavior of Ru(bpy)$\\rm{ {_{3}^{2+}}}$ ion-exchanged into the composite films has been characterized as a function of the amount of Nafion incorporated into the V2O5/Nafion composite. The composite film with 80% Nafion content has the largest pore diameter (4.19 nm) and yields the maximum ECL response for tripropylamine (TPA) because of the fast diffusion of analyte into the film with large pores. Due to the enlarged pore size and enhanced conductivity of the V2O5/Nafion composite, the present ECL sensor based on the compo...

2006-01-01

235

The importance of turbulence modelling in the design of a novel delivery system for a single-belt steel casting process  

Energy Technology Data Exchange (ETDEWEB)

In this work, a comprehensive model including heat transfer, fluid flow and solidification was used to evaluate the performance of a novel delivery system for a single-belt steel casting process. This near-net-shape casting, although still in development, is one of the most promising routes for casting of low-carbon steel in large scale. This paper focuses on the performance of a low-Re {kappa}-{epsilon} model that was employed to simulate the three-dimensional turbulent flows fully-coupled with heat transfer and macroscopic solidification. Simulations were run for the intended conditions of caster operation, and the results obtained with the {kappa}-{epsilon} were compared with the results obtained with an ad hoc viscosity model, where the molecular viscosity was boosted 100 times, uniformly throughout the computational domain. A semi-analytical solution was employed for validating the models and the results showed that the ad hoc viscosity model overestimated the thickness of the ...

2000-01-01

236

The control of radioactive wastes and the quality assurance requirements  

International Nuclear Information System (INIS)

For prolonged storage and eventual disposal radioactive wastes will be solidified to reduce the problems which accompany liquid waste whilst solid wastes will be encapsulated in an immobilising matrix. In the solidification and encapsulation process it will be important to produce a material in a form which is chemically stable, mechanically strong and which will not react with or allow free passage of groundwater. To this end a continuous check will be required to ensure that the various wastes are chemically compatible with the solidifying and binding matrices and that the associated processes are performed against a strict Quality Programme. The Quality Programme will be extensive requiring the specification of procedures for assessing the quality and nature of the wastes, the detailed operation of the solidification and/or encapsulation, the overpack requirements for transportation and the routines to be adopted with respect to storage or final disposal in the ...

237

Synchrotron PES and NEXAFS studies of self-assembled aromatic thiol monolayers on Au(1 1 1)  

Energy Technology Data Exchange (ETDEWEB)

Self-assembled monolayers (SAMs) on various metal, semiconductor or insulator substrates can be easily modified with specific functional groups of interest and have promising applications in surface wetting (hydrophobic/hydrophilic modification), tribology, corrosion protection, sensor electrodes modification, molecular and biomolecular recognition, protein adsorption, cell adhesion, and molecular- or organic-electronic device fabrications. In this paper, we highlight recent progress in the development of SAMs on solid substrates as well as their practical applications, with particular emphasis on the characterization of self-assembled aromatic thiol monolayers with different functional groups on Au(1 1 1) using synchrotron-based photoemission spectroscopy and near-edge X-ray absorption fine structure measurements. The SAM-related molecular orientation, electronic structures, and chemical bonding are presented. Using copper(II) phthalocyanine ...

2009-05-15

238

Study on Sm"1"."8Ce"0"."2CuO"4-Ce"0"."9Gd"0"."1O"1"."9"5 composite cathode materials for intermediate temperature solid oxide fuel cell  

British Library Electronic Table of Contents (United Kingdom)

Sm"1"."8Ce"0"."2CuO"4-xCe"0"."9Gd"0"."1O"1"."9"5 (SCC-xCGO, x=0-12vol.%) composite cathodes supported on Ce"0"."9Gd"0"."1O"1"."9"5 (CGO) electrolyte are studied for applications in IT-SOFCs. Results show that Sm"1"."8Ce"0"."2CuO"4 material is chemically compatible with Ce"0"."9Gd"0"."1O"1"."9"5 at 1000^oC. The composite electrode exhibits optimum microstructure and forms good contact with the electrolyte after sintering at 1000^oC for 4h. The polarization resistance (R"p) reduces to the minimum value of 0.17@Wcm^2 at 750^oC in air for SCC-CGO06 composite cathode. The relationship between R"p and oxygen partial pressure indicates that the reaction rate-limiting step is the surface diffusion of the dissociative adsorbed oxygen on the composite cathode.

2011-01-01

239

Study of the influence of alloying additions on the passivity of aluminum. Annual report 1 Dec 89-30 Nov 90  

Energy Technology Data Exchange (ETDEWEB)

Whereas supersaturated aluminum alloys demonstrate enhanced passivity, conventional aluminum alloys spontaneously pit in air-saturated chloride solutions. We have concentrated on three areas: evaluation and characterization of Al-W alloys, which exhibit the best corrosion performance of any alloy system studied to date; characterization of the passive-film structure of Al-Mo alloys; and production and characterization of Al-W and Al-Ta powders, which will be used for compaction into bulk material. Surface analysis of the Al-W passive films formed during polarization show surprising little oxidized solute compared to other alloys. These results indicate that the barrier layer formation and electrostatic repulsion mechanisms used to explain the passivity of other alloys are not involved here. Instead the W may act to stabilize the passive film structure in a way similar to the way molybdenum acts in Al-Mo alloys. That is oxidized molybdenum reduces the concentration ...

1991-03-01

240

Produced water treatment using polymeric resins; Resinas polimericas para tratamento da agua produzida  

Energy Technology Data Exchange (ETDEWEB)

The treatment and disposal of oily waters from oil production and refining processes represent an important technological pass for attendance of the ambient legislation and to the politics of the Cia of search of the environmental excellence. The reuse or reinjection of the co-produced water has been considered an interesting strategical alternative, however, the water quality requirement for these processes demands a pretreatment step, considering the exit effluent from primary and secondary treatment processes currently used. This work presents resulted of the polymeric resin development for tertiary treatment of oily waters with low oil and grasses content and fine solids, including the dissolved fraction. These resins can adsorb, in reversible form, organic components. Its high adsorption capacity is determined by the polarity, superficial area, range of porosity and a wide distribution of particle size and pore. Another important characteristic is the ...

2008-07-01

241

Present status and problems of high temperature coatings by thermal spraying system. Yosha ho ni yoru koon coatings by thermal spraying system  

Energy Technology Data Exchange (ETDEWEB)

This report outlines on the corrosive damage which is inherent to a high temperature environment and introduces on thermal spraying system taking an example of a gas turbine. The recent coatings by thermal spraying for high temperature environment are positively used in such applications as a hearth roll for continuous annealing, a roll for hot dipped steelplate, a solid electrolyte for fuel cell, boilers and rockets. The coating formed will be positively used because of a convenient thermal spraying and availability of various sprayable materials. This report describes the following items. Corrosive damage under the high temperature environment. Types of high temperature corrosive coating by a thermal spraying and utilization thereof. Outline of MCrAlX alloy, and merits thereof. Coating to a turbine wing by rduced pressure plasma thermal spraying. In general, it is urgently needed to establish the methods of characteristics measurement and the evaluation method ...

1990-10-30

242

Phase Chemistry of Tank Sludge Residual Components  

Energy Technology Data Exchange (ETDEWEB)

The US Department of Energy (DOE) has millions of gallons of high level nuclear waste stored in underground tanks at Hanford, Washington and Savannah River, South Carolina. These tanks will eventually be emptied and decommissioned. This will leave a residue of sludge adhering to the interior tank surfaces that may contaminate nearby groundwaters with radionuclides and RCRA metals. Performance assessment (PA) calculations must be carried out prior to closing the tanks. This requires developing radionuclide release models from the sludges so that the PA calculations can be based on credible source terms. These efforts continued to be hindered by uncertainties regarding the actual nature of the tank contents and the distribution of radionuclides among the various phases. In particular, it is of vital importance to know what radionuclides are associated with solid sludge components. Experimentation on actual tank sludges can be difficult, dangerous ...

2002-04-02

243

Operating experience with solidification of radioactive waste by a thin-film evaporator  

Energy Technology Data Exchange (ETDEWEB)

In the nuclear power stations of GDR the rough radioactive waste includes borat-containing evaporator bottoms and spent ion exchanger resins. For its final disposal in deep geological formations (rock salt mines) this waste has to be solidified. The experience of one year lasting operation of a steam heated thin-film evaporator (heating surface 2 m{sup 3}) for evaporator bottoms to be solidified with a solid content of 200-250 g/l are reported on. In short time such amount of water is abstracted from the rough waste that due to the borate content a hot high-viscous product passes from evaporator to waste drum and there solidifies like glass to monolith. The product quality depends on the adjustment of the flow-equilibrium in the evaporator. Boric acid is used as matrix for the radioactive residues. The residual water content of the solidified waste product was about 15-20%, the volume reduction was V{sub f}=5...6. In order to be sure to get a ...

1990-01-01

244

Operating experience with solidification of radioactive waste by a thin-film evaporator  

International Nuclear Information System (INIS)

In the nuclear power stations of GDR the rough radioactive waste includes borat-containing evaporator bottoms and spent ion exchanger resins. For its final disposal in deep geological formations (rock salt mines) this waste has to be solidified. The experience of one year lasting operation of a steam heated thin-film evaporator (heating surface 2 m"3) for evaporator bottoms to be solidified with a solid content of 200-250 g/l are reported on. In short time such amount of water is abstracted from the rough waste that due to the borate content a hot high-viscous product passes from evaporator to waste drum and there solidifies like glass to monolith. The product quality depends on the adjustment of the flow-equilibrium in the evaporator. Boric acid is used as matrix for the radioactive residues. The residual water content of the solidified waste product was about 15-20%, the volume reduction was V_f=5...6. In order to be sure to get a solidified ...

1990-06-01

245

Noise parameter forecasting and noise reduction design at working places in coal preparation plants  

Energy Technology Data Exchange (ETDEWEB)

Discusses the Methodological Directions for Expected Noise Calculation and Noise Reduction Design in Coal Preparation Plants developed at the Institute of Solid Fuel Preparation. Calculation of expected sound pressure levels is described. An exemplary chart of noise levels in the coal feed section of the coal preparation plant at the Taldinskii surface mine is presented. Procedures for planning noise pollution abatement measures and checking the expected noise levels are considered and explained on the example of the project of the coal crushing section in the Taldinskii plant (Kemerovugol' association) designed by Sibgiproshakht. A SMD-117 jaw crusher, 300 mm screen and a conveyor are to work in a space of 45,820 m{sup 3} with 30 m ceiling height. The expected noise level calculated for the working place of the crusher operator is 93-95 dBA without noise isolation and 85.5 dBA with noise isolation. A block diagram of a FORTRAN program ...

1989-02-01

246

Natural convection around a horizontal solid cylinder wrapped with a layer of fibrous or porous material  

International Nuclear Information System (INIS)

Heat losses in duct flow and heat transfer enhancement are investigated through an analysis of natural convection about a horizontal cylinder with a porous or fibrous coating. The porous substrate may be used for two purposes. According to its properties, it may be employed as an insulating material or as a means to surface augmentation. An optimization study is then carried out in order to find the best conditions that allow good thermal insulation or heat transfer rate improvement. The flow motion and heat transfer coefficient are predicted for various conditions. The results show that an efficient insulation which means less than 10% in heat losses is obtained for a porous layer thickness of 0.8x tube diameter and a permeability corresponding to Da #<=# 10"-"7. Nevertheless, there is a Darcy number limit above which convection must be accounted for. Porous or fibrous materials may also be used as a heat transfer augmentation technique. To achieve this goal, ...

2007-06-01

247

Modeling of hydrologic conditions and solute movement in processed oil shale waste embankments under simulated climatic conditions  

Energy Technology Data Exchange (ETDEWEB)

Commercial development of oil shale resources will produce vast quantities of processed shale waste. The presence of potentially toxic trace elements, inorganic salts, and potentially toxic residual organic constitutents make the disposal of vast quantities of processed shale a potential environmental problem. To be environmentally acceptable, processed shale disposal must: result in a physically stable structure, prevent or minimize release of potentially toxic compounds, and provide an economically acceptable post-land use. Water is the common element underlying all factors important to the environmental stability of disposed solid waste. The leaching and transport of solubles by water in processed shale embankments may result in degradation of local surface and groundwater quality. The major purpose of this research is to physically model, study, and describe the redistribution and movement of water and percolates in lifts of disposed ...

1990-07-01

248

Mechanisms controlling the composition influence on radiation hardening and embrittlement of iron-base alloys  

International Nuclear Information System (INIS)

Classification and ranking of the solid solution on their reaction to the irradiation is suggested on the basis of binary system structure controlled by mixing enthalpy sign, melting temperatures relation of components and solidus curves slope. Several combinations of these characteristics permit to pick out three groups of substitutional elements capable of forming the vacancy-solute atom complexes either low-mobile or fast-mobile ones as compared to monovacancies migration. The radiation hardening (and embrittlement) of binary alloys should be intensified respectively either due to heterogeneous point defect clusters nucleation on solute traps or due to solute atom clusters/ precipitate formation. A local cohesion decrease may also occur especially if low-melting elements (characterized by low surface energy) are segregating on internal sinks or grain boundaries. The predicted specifics of different alloy group under irradiation and during ...

1994-06-20

249

Initial efforts to evaluate the corrosion problems in the infrastructure of Mexican southeast coastal zones  

Energy Technology Data Exchange (ETDEWEB)

The infrastructure of the Mexican southeastern coastal zone is affected by corrosion problems which are due, mainly, to the construction bad practices and to the aggressive environmental agents (temp., Relative Humidity, chlorides). The first actions for knowing and controlling them have been taken on the coast of Progreso, Yucatan. Cylinders of solid concrete and others with an embedded rebar were constructed and exposed to the marine environment studying different variables like w/c ratio, time of curing, coated and uncoated rebars, chlorides and CO{sub 2} penetration and place of exposure with respect to the seashore. The cylinders were tested through corrosion potential and polarization resistance measurements in order to detect, in a first stage, the onset and propagation stages of the corrosion processes and to correlate the apparent corrosion current density (Icorr.) with the chloride concentration in the rebar surface. These results are ...

1995-10-01

250

Incorporation of flying ashes into cold-stabilized argillaceous products  

Energy Technology Data Exchange (ETDEWEB)

Clay-based materials can be cold-stabilized using binder and formed by extrusion. This paper deals with the properties of such materials under the influence of silico-aluminous flying ashes addition. Flying ashes are solid industrial wastes produced by coal combustion. Characteristics of ashes bearing clay-based products, such as dimensional stability, water and mechanical resistance, accelerated aging, are considerably improved with respect to simple clay-binder mixtures. This is principally due to a better hydration of the binder in ashes-bearing mixtures because of: a higher free-water availability as a consequence of the smaller specific surface of ash grains, the filler effect of ash grains which do not participate to the reactions, the specific property of silico-aluminous ashes that can fix the lime in presence of water to produce hydrated compounds. These ashes-bearing clay based materials can have the same qualities as classical ...

1996-12-01

251

Gate-oxide integrity for polysilicon thin-film transistors: a comparative study for ELC, MILC and SPC crystallized active polysilicon layer  

International Nuclear Information System (INIS)

In this paper, we present the results of Plasma-Enhanced Chemical Vapor Deposition gate-oxide (SiO_2) integrity on ELC (excimer-laser-crystallized), MILC (metal-induced lateral-crystallized) and SPC (solid-phase-crystallized) polysilicon films. We observed that gate oxide strength of poly-Si TFT strongly depends on the crystallization method for the active silicon layer. In the case of ELC films, asperities on the silicon surface reduce the SiO_2 breakdown field significantly. The metallic contaminants in MILC films are responsible for a deleterious impact on gate oxide integrity. Among the three cases, the SiO_2 breakdown field was the highest for the SPC silicon films. The breakdown fields at the 50 % failure points in Weibull plots for the ELC, MILC and SPC cases were 5.1 MV/cm, 6.2 MV/cm, and 8.1 MV/cm, respectively. We conclude that the roughness and metallic contamination of the poly-Si films are the main factors that cause enhanced ...

2006-01-01

252

Fluid flow visualization with neutron radiography. [Using collimated beam of neutrons  

Energy Technology Data Exchange (ETDEWEB)

A technique was developed that permits fluid flow to be visualized even where the flow is completely shrouded by metal. The technique employs real-time neutron radiography, which is similar to x-ray radiography except a collimated beam of neutrons is used. Various combinations of neutron-opaque tracer materials were tested with neutron-transparent fluid. Neutron opaque tracers, such as solid particles, fluid droplets, and streaklines were imaged through metal walls as they convected in neutron-transparent ambient fluid. Visualization of bubbles/voids were evaluated for possible future applications. Surface-flow patterns were also imaged by using neutron-opaque tufts. These techniques were evaluated for image contrast, resolution, and the ability to accurately track fluid flow fields. The techniques were also modeled to optimize contrast in various flow configurations. Imaging techniques such as real-time video, high speed video, and ...

1991-01-01

253

Fluid flow visualization with neutron radiography  

International Nuclear Information System (INIS)

A technique was developed that permits fluid flow to be visualized even where the flow is completely shrouded by metal. The technique employs real-time neutron radiography, which is similar to x-ray radiography except a collimated beam of neutrons is used. Various combinations of neutron-opaque tracer materials were tested with neutron-transparent fluid. Neutron opaque tracers, such as solid particles, fluid droplets, and streaklines were imaged through metal walls as they convected in neutron-transparent ambient fluid. Visualization of bubbles/voids were evaluated for possible future applications. Surface-flow patterns were also imaged by using neutron-opaque tufts. These techniques were evaluated for image contrast, resolution, and the ability to accurately track fluid flow fields. The techniques were also modeled to optimize contrast in various flow configurations. Imaging techniques such as real-time video, high speed video, and ...

1764-01-01

254

Double-Edge Molecular Measurement of Lidar Wind Profiles in the VALID Campaign  

Science.gov (United States)

We have developed a transportable container based direct detection Doppler lidar based on the double-edge molecular technique. The pulsed solid state system was built at the University of Geneva. It was used to make range resolved measurements of the atmospheric wind field as part of the VALID campaign at the Observatoire de Haute Provence in Provence, France in July 1999. Comparison of our lidar wind measurements, which were analyzed without knowledge of the results of rawinsonde measurements made under the supervision of ESA, show good agreement with these rawinsondes. These are the first Doppler lidar field measurements made with an eyesafe direct detection molecular-based system at 355 nm and serve as a demonstrator for future spaceborne direct detection wind systems such as the Atmospheric Dynamics mission. Winds are an important contributor to sea surface temperature measurements made with the Tropical Rainfall Measuring Mission (TRMM) ...

2000-01-01

255

Detection system characteristics using sup 252 Cf ionization chambers  

Energy Technology Data Exchange (ETDEWEB)

Because the number of neutrons and gamma rays and the energy spectrum of particles from spontaneous fission are well characterized for {sup 252}Cf, it can be used as a timed source of fission neutrons and gamma rays. The first such usage incorporated a {sup 252}Cf source into gas scintillators. This paper describes a timed source of neutrons and gamma rays made by depositing {sup 252}Cf on one electrode of a parallel plate ionization chamber that can then be used for determining detection-system characteristics. The emission time of neutrons from spontaneous fission has also been determined by recording the emission time of prompt gamma rays from a {sup 252}Cf source (not incorporated into a detector) adjacent to the surface of a solid or liquid scintillator. This well characterized source of neutrons can thus be used as a randomly pulsed source for a variety of applications. This paper illustrates the use of this type of source to determine ...

1990-01-01

256

Control of microbially generated hydrogen sulfide in produced waters  

Energy Technology Data Exchange (ETDEWEB)

Production of hydrogen sulfide in produced waters due to the activity of sulfate-reducing bacteria (SRB) is a potentially serious problem. The hydrogen sulfide is not only a safety and environmental concern, it also contributes to corrosion, solids formation, a reduction in produced oil and gas values, and limitations on water discharge. Waters produced from seawater-flooded reservoirs typically contain all of the nutrients required to support SRB metabolism. Surface processing facilities provide a favorable environment in which SRB flourish, converting water-borne nutrients into biomass and H{sub 2}S. This paper will present results from a field trial in which a new technology for the biochemical control of SRB metabolism was successfully applied. A slip stream of water downstream of separators on a produced water handling facility was routed through a bioreactor in a side-steam device where microbial growth was allowed to develop fully. This ...

1995-12-31

257

Contribution to the study of sputtering and damage of uranium dioxide by fast heavy ions; Contribution a l'etude de la pulverisation et de l'endommagement du dioxyde d'uranium par les ions lourds rapides  

Energy Technology Data Exchange (ETDEWEB)

Swift heavy ion-solid interaction leads in volume to track creation and on the surface to the ejection of particles into the vacuum. To learn more about initial mechanisms of track formation, we are focused on the sputtering of uranium dioxide by fast heavy ions. This present study is exclusively devoted to the influence of the electronic stopping power on the emission of neutral particles and especially on their angular distribution. These measurements are completed by those of the ions emitted from UO{sub 2} targets bombarded with swift heavy ions. The whole experimental results give access to: i) the nature of the sputtered particles; ii) the charge state of the emitted particles; iii) the direction of ejection of the sputtered particles ; iv) the sputtering yields deduced from the angular distributions. These results are compared to the prediction of the sputtering models proposed in the literature and it seems that the supersonic gas flow ...

2001-03-01

258

Chromized/siliconized diffusion coatings for iron-base alloy by pack cementation  

Energy Technology Data Exchange (ETDEWEB)

This paper reports that the co-deposition of chromium and silicon into a 2.25Cr-1.0Mo-0.15C steel, alloy 800, and type 304 stainless steel has been achieved using the pack cementation process. The ferritic coating produced on the 2.25 Cr-1.0Mo steel was approximately 225 {mu}m (9 mils) thick, whereas the inward diffusion of chromium and silicon produced a two-phase structure of ferrite and austenite for type 304. Chromium and silicon were incorporated into the austenitic solid solution upon diffusion into alloy 800. All coatings had approximately 25 to 35 wt% Cr and 2 to 3% Si at the surface. Cyclic oxidation testing in air of the coated 2.25Cr-1.0Mo steel (T = 700{degrees} C) and type 304 (T = 1035{degrees} C) showed a dramatic decrease in the oxidation kinetics compared to the original uncoated alloys. The cyclic oxidation of alloy 800 was also improved.

1991-09-01

259

Structure and property relationship in the mixed-conducting Sr-Fe-Co-O system.  

Energy Technology Data Exchange (ETDEWEB)

Mixed-conducting ceramic oxides have potential uses in high-temperature electrochemical applications such as solid oxide fuel cells, advanced batteries, sensors, and oxygen-permeable membranes. The Sr-Fe-Co-O system combines high electronic/ionic conductivity with appreciable oxygen permeability at elevated temperatures. Dense ceramic membranes made of this material can be used to separate high-purity oxygen from air without the need for external electrical circuitry, or to partially oxidize methane to produce syngas. Samples of Sr{sub 2}Fe{sub 3{minus}x}Co{sub x}O{sub y} (with x = 0, 0.6, 1.0, and 1.4) were prepared by solid-state reaction in atmospheres with various oxygen partial pressures (pO{sub 2}) and were characterized by X-ray diffraction, scanning electron microscopy, and electrical conductivity measurements. Phase components of the samples are dependent on cobalt concentration and synthesis pO{sub 2}. Total conductivity increases ...

1998-05-18

260

Probing anodic reaction kinetics and interfacial mass transport of a direct formic acid fuel cell using a nanostructured palladium-gold alloy microelectrode  

International Nuclear Information System (INIS)

The anodic reaction kinetics and interfacial mass transport of a direct polymer electrolyte membrane formic acid fuel cell have been investigated in an all solid-state electrochemical cell using a highly active nanostructured palladium-gold alloy microelectrode as an in situ probe. Well-defined 'S-shaped' steady-state cyclic voltammograms exhibiting current-rising region at lower overpotentials and limiting current region at higher overpotentials have been first obtained for the electrochemical oxidation of formic acid at varying temperature. The 'S-shaped' steady state polarization curves and chronoamperometric curves enable convenient measurements of the anodic reaction kinetics and interfacial mass transport of formic acid under real polymer electrolyte membrane conditions. It is encouragingly found that formic acid can be directly oxidized to CO2 with the first electron transfer being the likely rate-determining step and the formation of ...

2009-07-30

261

Organic light-emitting devices based on solution-processible quinolato-complex supramolecules  

International Nuclear Information System (INIS)

This paper discusses a new type of supramolecular material tris{5-N-[3-(9H-carbazol-9-yl)propyl]-N-(4-methylphenyl) aminesulfonyl-8-hydroxyquinolato} aluminum(III), Al(SCarq)3, which we synthesized using three 5-N-[3-(9H-carbazol-9-yl)propyl]-N-(4-methylphenyl) aminesulfonyl-8-hydroxyquinoline as bidentate ligands. The peak photoluminescence in the solid phase appears at 488 nm. In cyclic voltammetric measurement, two oxidation peaks, which were obtained at -5.6 and -5.9 eV, correspond to HOMO sites of carbazoyl and aluminum quinolates, respectively. In the investigation of solid morphological thin film, the flat surface was investigated using an atomic force microscope. The root mean square (rms) and mean roughness (Ra) were respectively measured to be 0.427 and 0.343 nm. For the fabrication of organic light-emitting devices (OLEDs) using spin-coating techniques, the turn-on voltage and maximum luminescence of the ...

2009-02-15

262

Numerical study of steady/unsteady flow and heat transfer in porous media using a characteristics-based matrix-free implicit FV method on unstructured grids  

International Nuclear Information System (INIS)

In this study, a high-resolution characteristic-based finite-volume (FV) method on unstructured grids [Int. J. Numer. Method Eng. 50 (2001) 11; Int. J. Heat Fluid Flow 21 (2000) 432] is extended by a matrix-free implicit dual-time stepping scheme for the numerical simulation of steady and unsteady flow and heat transfer with porous media. The method has been used to study the characteristics of a complex problem: flow and heat transfer in a channel with multiple discrete porous blocks, which was originally proposed by Huang and Vafai [J. Thermophys. Heat Transfer 8 (3) (1994) 563]. In addition, flow and heat transfer in a channel partially or fully filled with porous layers and containing solid protruding blocks with constant heat flux on its lower surface are also investigated in details. Hydrodynamic and heat transfer results are reported for both steady and transient flow cases. In particular, the effects of Darcy and Reynolds numbers on ...

2004-12-01

263

Multiphase integral reacting flow computer code (ICOMFLO): User`s guide  

Energy Technology Data Exchange (ETDEWEB)

A copyrighted computational fluid dynamics computer code, ICOMFLO, has been developed for the simulation of multiphase reacting flows. The code solves conservation equations for gaseous species and droplets (or solid particles) of various sizes. General conservation laws, expressed by elliptic type partial differential equations, are used in conjunction with rate equations governing the mass, momentum, enthalpy, species, turbulent kinetic energy, and turbulent dissipation. Associated phenomenological submodels of the code include integral combustion, two parameter turbulence, particle evaporation, and interfacial submodels. A newly developed integral combustion submodel replacing an Arrhenius type differential reaction submodel has been implemented to improve numerical convergence and enhance numerical stability. A two parameter turbulence submodel is modified for both gas and solid phases. An evaporation submodel treats not only droplet ...

1997-11-01

264

In situ x-ray diffraction measurement of Pd/sub 2/Si transformation kinetics using a linear position-sensitive detector  

Science.gov (United States)

The x-ray diffraction technique described previously for measurement of growth kinetics of Pd/sub 2/Si layers from their solid state reaction couples has been extended by the use of a one-dimensional position-sensitive detector (PSD). Additionally, the method has been extended to include measurement of the Pd layer. A detailed description of the experimental arrangement and analytical procedures is presented. The kinetics of epitaxial Pd/sub 2/Si film growth were measured in situ over a range of 170--230 /sup 0/C. The PSD results, using data obtained from both the Pd/sub 2/Si and Pd layers, were able to confirm parabolic growth behavior for the Pd/sub 2/Si film. The rate constants followed Arrhenius behavior and yielded an activation energy of E = 1.32 +- 0.07 eV with a prefactor k/sub 0/ = 0.49 cm/sup 2//s for the Pd/sub 2/Si layer analysis and E = 1.34 +- 0.17 eV with a prefactor of 0.72 cm/sup 2//s for the Pd layer analysis. The PSD technique significantly ...

1988-02-15

265

High lithium ion conductive solid electrolytes. Ko lithium ion dodensei kotai denkaishitsu no kenkyu  

Energy Technology Data Exchange (ETDEWEB)

The paper describes a lithium battery researched on under the Moonlight Project which is a long life secondary battery with high energy density and high power density. Using as a base a Li4SiO4 system which exhibits stable and high Li[sup +] conductivity as solid electrolyte material, partial Si[sup 4+] is replaced with divalent ions such as B[sup 3+] and Al[sup 3+] or divalent ions such as Ni[sup 2+] and Co[sup 2+], by which Li[sup +] for electric charge compensation can be increased and conductivity is enhanced. As to a LiTi2P3O12 system, Ti[sup 4+] is replaced with Sc[sup 3+] and Y[sup 3+]. In both systems, by replaCing Si[sup 4+] or Ti[sup 4+] with trivalent metal ions and increasing mobile Li[sup +], those with ion conductivity exceeding that at 300[degree]C, 10[sup -3]Scm[sup -1], can be developed. TiS2 and NiPS3 are prepared as cathode material and miniature cells are trially fabricated. Various polarization phenomena are observed and a lot of improvements ...

1993-02-26

266

Growth rate control and solid-gas modeling of TFA-YBa_2Cu_3O_7 thin film processing  

International Nuclear Information System (INIS)

The trifluoroacetate metal-organic decomposition route to YBa_2Cu_3O_7 film growth was investigated in order to bring new insights in the growth mechanism and its dependence on processing conditions and critical current density. Precursor films were processed on LaAlO_3 substrates at different total pressure, oxygen partial pressure, water vapor partial pressure, and volume gas flow rate keeping the growth temperature at 740 "0C. The influence of these various experimental parameters on the film growth rate, which was evaluated by in situ electrical resistance measurements, was studied thoroughly. It was found that the growth rate is nearly independent of the oxygen pressure and proportional to the square root of the water pressure. Additionally, the growth rate increases with a decrease of the total pressure or an increase of the gas flow rate. An empirical multi-exponential model simulates the experimental data, however, a better understanding was achieved using a theoretical ...

2010-03-01

267

Effects of pH and phosphate on metal distribution with emphasis on As speciation and mobilization in soils from a lead smelting site  

Energy Technology Data Exchange (ETDEWEB)

Arsenic in soils from the Asarco lead smelter in East Helena, Montana was characterized by X-ray absorption spectroscopy (XAS). Arsenic oxidation state and geochemical speciation were analyzed as a function of depth (two sampling sites) and surface distribution. These results were compared with intensive desorption/dissolution experiments performed in a pH stat reactor for samples from the site with the highest degree of As heterogeneity. The objectives of the study were to investigate the solid-phase geochemical As speciation, assess the speciation of As in solutions equilibrated with the solids under controlled pH (pH=4 or 6) and Eh (using hydrogen or air) environments, observe the effects of phosphate on the release of As into solution, and examine the effects of phosphate on metal mobility in the systems. Arsenic was predominantly found in the As(V) valence state, though there was evidence that As(III) and As(0) were ...

2005-06-01

268

Effect of various coal contaminants on the performance of solid oxide fuel cells: Part I. Accelerated testing  

Energy Technology Data Exchange (ETDEWEB)

The contaminants that are potentially present in the coal-derived gas stream and their thermochemical nature are discussed. Accelerated testing was carried out on Ni-YSZ/YSZ/LSM solid oxide fuel cells (YSZ: yttria stabilized zirconia and LSM: lanthanum strontium manganese oxide) for eight main kind of contaminants: CH{sub 3}Cl, HCl, As, P, Zn, Hg, Cd and Sb at the temperature range of 750-850 C. The As and P species, at 10 and 35 ppm, respectively, resulted in severe power density degradation at temperatures 800 C and below. SEM and EDX analysis indicated that As attacked the Ni region of the anode surface and the Ni current collector, caused the break of the current collector and the eventual cell failure at 800 C. The phosphorous containing species were found in the bulk of the anode, they were segregated and formed ''grain boundary'' like phases separating large Ni patches. These species are presumably ...

2009-09-05

269

Dosimetric evaluation of multi-pattern spatially fractionated radiation therapy using a multi-leaf collimator and collapsed cone convolution superposition dose calculation algorithm  

International Nuclear Information System (INIS)

Purpose: In this paper, we present an alternative to the originally proposed technique for the delivery of spatially fractionated radiation therapy (GRID) using multi-leaf collimator (MLC) shaped fields. We employ the MLC to deliver various pattern GRID treatments to large solid tumors and dosimetrically characterize the GRID fields. Methods and materials: The GRID fields were created with different open to blocked area ratios and with variable separation between the openings using a MLC. GRID designs were introduced into the Pinnacle"3 treatment planning system, and the dose was calculated in a water phantom. Ionization chamber and film measurements using both Kodak EDR2 and Gafchromic EBT film were performed in a SolidWater phantom to determine the relative output of each GRID design as well as its spatial dosimetric characteristics. Results: Agreement within 5.0% was observed between the Pinnacle"3 predicted dose distributions and the ...

2009-10-01

270

Effects of Multi-ion Irradiation on Microstructural Changes in Lithium Titanate  

Energy Technology Data Exchange (ETDEWEB)

Full text of publication follows: Li{sub 2}TiO{sub 3} is regarded as one of the most suitable candidates for the solid tritium breeder material of D-T fusion reactors. It is known that, in an operating fusion reactor, the radiation damage in Li{sub 2}TiO{sub 3} will be caused by fast neutrons, energetic tritons and helium ions generated in {sup 6}Li(n,{alpha}){sup 3}H reaction. The irradiation damage caused by such radiation may result in the microstructural changes, and the changes may affect the characteristics of Li{sub 2}TiO{sub 3} such as tritium release behavior. Thus the study of irradiation defects and microstructural changes caused by irradiation in Li{sub 2}TiO{sub 3} is essential to evaluate its irradiation performance. Simulation of the fusion reactor environment and hence the study of a synergistic effect of atomic displacement damage in Li{sub 2}TiO{sub 3} are approached by a simultaneous irradiation with 'triple' ion beams which ...

2007-07-01

271

Volatilization of fluorides from solid uranium(IV)fluoride  

International Nuclear Information System (INIS)

... deposition evaporation fission products fluorides iodine 134 laboratory

1971-02-01

273

The Growth of an Extrapancreatic Solid Pseudopapillary Tumor from the Greater Omentum: A Case Report  

Energy Technology Data Exchange (ETDEWEB)

A solid pseudopapillary tumor is an uncommon tumor of the pancreas that rarely metastasizes to other organs and usually shows good prognosis. An extrapancreatic tumor arising from a solid pseudopapillary tumor is very rare. We report a case of an atypical extrapancreatic solid pseudopapillary tumor that arose from the great omentum and disseminated to the peritoneum, and discuss the radiologic findings, including the CT, US, and MRI.

2010-01-15

274

The Growth of an Extrapancreatic Solid Pseudopapillary Tumor from the Greater Omentum: A Case Report  

International Nuclear Information System (INIS)

A solid pseudopapillary tumor is an uncommon tumor of the pancreas that rarely metastasizes to other organs and usually shows good prognosis. An extrapancreatic tumor arising from a solid pseudopapillary tumor is very rare. We report a case of an atypical extrapancreatic solid pseudopapillary tumor that arose from the great omentum and disseminated to the peritoneum, and discuss the radiologic findings, including the CT, US, and MRI

2010-01-01

276

Report of the Government Industrial Research Institute, Osaka, No. 388, February 1993. High lithium ion conductive solid electrolytes  

Energy Technology Data Exchange (ETDEWEB)

Research investigating applicability of lithium salts for solid electrolyte batteries was described. The studies included determinations of lithium ion conductivities in solid electrolyte systems based on Li4SiO4, LiTi2(PO4)3, and ceramic materials. Research on all solid state lithium cells utilizing TiS2 NiPS3 electrodes was also reported.

1993-01-01

278

Plasma Technologies for Fuel Processing  

International Science & Technology Center (ISTC)

Plasma Technologies of Solid Fuels Processing for Power Engineering and Metallurgy

287

The Modification of Polymer Surfaces and the Fabrication of ...  

Science.gov (United States)

... spatially defined fashion. Many surface modification techniques require a sequential chemical treatment of the surface.6 ...

1993-06-10

288

Surface Temperature - My NASA Data  

Science.gov (United States)

Surface temperature is measured with an infrared thermometer. Measuring Surface Temperature. Nine sample points are selected with a site of uniform land ...

289

Surface Crystallization and Composition of Spinel and Acmite in High-Level Waste Glass  

Science.gov (United States)

Surface crystallization and surface-to-bulk ratio in high-level waste glasses.

2000-07-10

290

Solids distribution in tall tanks  

British Library Electronic Table of Contents (United Kingdom)

Abstract Uniformly distributing slurry solids in -tall- (-2:1 aspect ratio) process vessels is a significant challenge in the chemical industry. This work determined the performance of various multi-tier agitation systems in uniformly distributing a settling solid throughout water in a -tall- laboratory vessel. It used a 0.445-m ID Plexiglas tank, with a slurry height of 0.889-m, to determine how solids distribution changes with solids loading (wt.%), impeller speed, and impeller type. Some impeller types uniformly distributed the solids even before energy input exceeded 1.00-W/kg. Significantly higher energy improved solids distribution little because flow within the vessel eventually became choked.

2011-01-01

291

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

Science.gov (United States)

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

1987-03-01

292

Small hemielliptic dielectric lens antenna analysis in 2-D: boundary integral equations versus geometrical and physical optics  

CERN Document Server

We assess the accuracy and relevance of the numerical algorithms based on the principles of Geometrical Optics (GO) and Physical Optics (PO) in the analysis of reduced-size homogeneous dielectric lenses prone to behave as open resonators. As a benchmark solution, we use the Muller boundary integral equations discretized with trigonometric Galerkin scheme that has guaranteed and fast convergence as well as controllable accuracy. The lens cross-section is chosen typical for practical applications, namely an extended hemiellipse whose eccentricity satisfies the GO focusing condition. The analysis concerns homogeneous lenses made of rexolite, fused quartz, and silicon with the size varying between 3 and 20 wavelengths in free space. We consider the 2-D case with both E- and H-polarized plane waves under normal and oblique incidence, and compare characteristics of the near fields.

2010-01-01

293

P-T and structural constraints of lawsonite and epidote blueschists from Liberty Creek and Seldovia: Tectonic implications for early stages of subduction along the southern Alaska convergent margin  

British Library Electronic Table of Contents (United Kingdom)

The southern Alaska convergent margin contains several small belts of sedimentary and volcanic rocks metamorphosed to blueschist facies, located along the Border Ranges fault on the contact between the Wrangellia and Chugach terranes. These belts are significant in that they are the most inboard, and thus probably contain the oldest record of Triassic-Jurassic northward-directed subduction beneath Wrangellia. The Liberty Creek HP-LT schist belt is the oldest and the innermost section of the Chugach terrane. Within this belt lawsonite blueschists contains an initial high-pressure assemblage formed by lawsonite+phengite+chlorite+sphene+albite+/-apatite+/-carbonates and quartz. Epidote blueschists are composed of sodic, sodic-calcic and calcic amphiboles+epidote+phengite+chlorite+albite+sphen...

2011-01-01

294

Optimal design and preparation of beta-SiAlON multiphase materials from natural clay  

International Nuclear Information System (INIS)

Beta-SiAlON powders have been synthesized using natural clay containing kaolin and quartz by carbothermal reduction and nitridation (CRN), then beta-SiAlON bonded corundum multiphase materials have been sintered using the as prepared powders. The results indicated that both the holding time and sintering temperature are relatively significant in accordance with optimal analysis by orthogonal method. Reaction process can be briefly interpreted by means of X-ray Diffraction and Difference Temperature Analysis as well as phase diagram principle. Bending strength and bulk density were measured in SiAlON in situ bonded corundum materials with doped various sintering agents. Furthermore, the relevant mechanical properties and microstructure were discussed in detail.

295

Modification of streaming potential by precipitation of calcite in a sand-water system: laboratory measurements in the pH range from 4 to 12  

British Library Electronic Table of Contents (United Kingdom)

SUMMARY Spontaneous potentials associated with volcanic activity are often interpreted by means of the electrokinetic potential, which is usually positive in the flow direction (i.e. Zeta potential of the rock is negative). The water-rock interactions in hydrothermal zones alter the primary minerals leading to the formation of secondary minerals. This work addresses the study of calcite precipitation in a sand composed of 98 per cent quartz and 2 per cent calcite using streaming potential measurements. The precipitation of calcite as a secondary mineral phase, inferred by high calcite saturation indices and by a fall in permeability, has a significant effect on the electrokinetic behaviour, leading to a significant reduction in the Zeta potential (in absolute value) and even a change in si...

2006-01-01

296

Hydrogen production from solar thermal dissociation of natural gas: development of a 10kW solar chemical reactor prototype  

British Library Electronic Table of Contents (United Kingdom)

This study addresses the solar thermal decomposition of natural gas for the co-production of hydrogen, as well as Carbon Black as a high-value nano-material, with the bonus of zero CO2 emissions. The work focused on the development of a medium-scale solar reactor (10kW) based on the concept of indirect heating. The solar reactor is composed of a cubic cavity receiver (20cm side), which absorbs concentrated solar irradiation through a quartz window via a 9cm-diameter aperture. The reacting gas flows inside four graphite tubular reaction zones that are settled vertically inside the cavity. Experimental results were as follows: methane conversion and hydrogen yield of up to 98% and 90%, respectively, were achieved at 1770K, and acetylene was the most important by-product, with a mole fraction...

2009-01-01

297

Feasibility investigations of growing and characterizing gallium arsenide crystals in ribbon form. Quarterly progress report 1 Jan-31 Mar 1975  

International Nuclear Information System (INIS)

The feasibility of continuous production of gallium arsenide ribbon single crystals, by passage of a molten zone through boron-oxide encapsulated GaAs feedstock, is being investigated. Polycrystalline GaAs ribbons have been grown in graphite boats by passage of a wide zone through B2O3-encapsulated feed-stock, confined by a quartz cover plate. Failure to remove the encapsulant above its glass transition temperature, however, resulted in cracking of the ribbons on cooling to room temperature. In order to study the crucial zone melting step in isolation from the encapsulation steps of the continuous process, a constrained-zone melting apparatus has been constructed in which the boron oxide serves only as a sealant to suppress arsenic vaporization. Large grained polycrystalline samples have been produced with this apparatus.

298

ESR dating of fault rocks  

Energy Technology Data Exchange (ETDEWEB)

Past movement on faults can be dated by measurement of the intensity of ESR signals in quartz. These signals are reset by local lattice deformation and local frictional heating on grain contacts at the time of fault movement. The ESR signals then trow back as a result of bombardment by ionizing radiation from surrounding rocks. The age is obtained from the ratio of the equivalent dose, needed to produce the observed signal, to the dose rate. Fine grains are more completely reset during faulting, and a plot of age vs grain size shows a plateau for grains below critical size : these grains are presumed to have been completely zeroed by the last fault activity. We carried out ESR dating of fault rocks collected from the Yangsan fault system. ESR dates from the this fault system range from 870 to 240 ka. Results of this research suggest that long-term cyclic fault activity continued into the pleistocene.

2002-03-15

299

A study on yellow luminescence in O and C ion implanted GaN  

International Nuclear Information System (INIS)

The effects of O and C ion implantation with different implantation doses on the yellow luminescence (YL) from unintentional doped n-type GaN have been studied by the photoluminescence (PL) spectra. O and C ions were implanted in the GaN samples with different doses from 1.0 x l013 to 1.0 x l017cm-2. Post-annealing was done in a quartz open-tube furnace under flowing N2 gas for 30 min at 950 degree C. By comparing with N ion implanted samples, it is assumed that different deep-level centers involving in the YL were produced in GaN after O and C ion implantation. In addition, with a dose of 1017 cm-2, the concentration of deep C centers involving in the YL was enhanced markedly. (authors)

2008-08-01

300

A method for sorting irradiated substances through coloration  

International Nuclear Information System (INIS)

L'invention concerne un procede de triage de cristaux irradies. Ce procede non destructeur comporte l'irradiation des cristaux par un rayonnement ionisant pendant une duree et avec une intensite telles qu'il se forme des centres colores distinctifs dans les matieres contenant des ions aluminium. Les cristaux colores qui correspondent en teinte et en profondeur de couleur a des teneurs en aluminium en dehors de la teneur desiree peuvent etre separes. On peut isoler ainsi des matieres de quartz, de verre, de silicates exemptes d'aluminium dans un melange, ou bien on peut choisir des fractions de ces matieres, chacune contenant une teneur uniforme en aluminium.

301

Solid state alkali metal-halogen cell  

Energy Technology Data Exchange (ETDEWEB)

A solid electrolyte cell comprises an alkali metal anode, e.g. lithium, a halogen-containing organic polymer cathode and a solid elecrolyte between the anode and the cathode. The cathode comprises iodine-containing vacuum-cyclised polyacrylonitrile, and the solid electrolyte is preferably lithium iodide and halogen-free vacuum-cyclised polyacrylonitrile. This patent also discloses the use of isotactic polyacrylonitrile, a method of making a cathode comprising iodine-containing vacuum-cyclised polyacrylonitrile, and novel methods of making the solid elecrolyte cells described.

1988-04-26

302

Anaerobic digestion of municipal solid waste: Technical developments  

Energy Technology Data Exchange (ETDEWEB)

The anaerobic biogasification of organic wastes generates two useful products: a medium-Btu fuel gas and a compost-quality organic residue. Although commercial-scale digestion systems are used to treat municipal sewage wastes, the disposal of solid organic wastes, including municipal solid wastes (MSW), requires a more cost-efficient process. Modern biogasification systems employ high-rate, high-solids fermentation methods to improve process efficiency and reduce capital costs. The design criteria and development stages are discussed. These systems are also compared with conventional low-solids fermentation technology.

1996-01-01

303

Structure and magnetic properties of nanostructural strontium ferrite prepared by mechanochemical treatment  

International Nuclear Information System (INIS)

Full text: It was recently-established for hexagonal barium ferrite-industrially important magnetically hard material that refinement of the crystallite dimensions into the nanoscale regime, typically #<=# 10 nm, leads after heat treatment at temperatures 800-1000 deg C to significant coercivity increase of up to 6.5 kOe (#approx#3-4 times) with saturation magnetisation values of 50-55 emu/g (#approx#95% of bulk at room temperature). High-energy mechanochemical processing has been applied to prepare nanostructural (nanocrystalline-amorphous) composites. High resolution electron microscopy studies reveal that the enhancement of the final magnetic properties was due to formation of magnetically noninteracting #approx#l,#mu#m Ba-ferrite particles with 5-10 nm amorphous surface layer - depending on annealing parameters. Similar situation was established also for ball milled strontium ferrite (SrFe_1_2O_1_9) powders where short annealing 4 h at 1000 deg C produced ...

304

Shape evolution of nanostructures by thermal and ion beam processing. Modeling and atomistic simulations  

International Nuclear Information System (INIS)

Single-crystalline nanostructures often exhibit gradients of surface (and/or interface) curvature that emerge from fabrication and growth processes or from thermal fluctuations. Thus, the system-inherent capillary force can initiate morphological transformations during further processing steps or during operation at elevated temperature. Therefore and because of the ongoing miniaturization of functional structures which causes a general rise in surface-to-volume ratios, solid-state capillary phenomena will become increasingly important: On the one hand diffusion-mediated capillary processes can be of practical use in view of non-conventional nanostructure fabrication methods based on self-organization mechanisms, on the other hand they can destroy the integrity of nanostructures which can go along with the failure of functionality. Additionally, capillarity-induced shape transformations are effected and can thereby be ...

2009-05-12

305

Probabilistic energy based model for prediction of transverse cracking in cross-ply laminates  

Energy Technology Data Exchange (ETDEWEB)

In the present paper an attempt is made to describe transverse cracking of cross-ply ([0{sup o}{sub n}/90{sup o}{sub m}]{sub s}) laminates subjected to an external applied load and a temperature change. For this purpose a new method is suggested which was developed on the basis of the energy balance based finite fracture criterion suggested by Hashin (1996) [Hashin, Z., 1996. J. Mech. Phys. Solids 44, 1129]. In this approach the value of the specific surface energy (the critical energy release rate) is assumed to be dependent on a random microdamage distribution in the material. Hence, it is assumed to be a random function of location. A new probabilistic technique is developed to take this randomness into consideration. It is shown that only one unknown probabilistic function is required, namely the probability density function of the specific surface energy. This is determined by fitting the external stress and the ...

2005-01-01

306

Mechanism of r. f. plasma nitriding of Ti-6Al-4V alloy  

Energy Technology Data Exchange (ETDEWEB)

The objective of the current study was the gradual development of the formation of the nitride layer during inductive r.f. plasma nitriding. The study centers on characterization of refined layers and plasma diagnostics in the vicinity of the sample, and raises critical questions of how the layers and interfacial microstructure might affect the near-surface properties. The composition of the plasma near the surface of the sample (plasma layer) was examined by optical emission spectroscopy and mass spectrometry during plasma nitriding and while sputtering the sample after the nitriding process. It was observed that during the nitriding process, the plasma layer contains Ti, NH[sub n] species, N (or/and N[sup +]), H[sub n] species (or/and H[sup +][sub 2]). However, when the nitrided sample was exposed to argon plasma, Ti, Al and NH were observed. It was found that two distinct sublayers, comprising [delta]-TiN and [delta]-TiN + [epsilon]-Ti[sub ...

1993-08-15

307

Kinetics of Pd/sub 2/Si layer growth measured by an x-ray diffraction technique  

Science.gov (United States)

An x-ray diffraction approach has been developed for determination of the kinetics of growth of Pd/sub 2/Si layers. Epitaxial Pd/sub 2/Si films were grown on Si(111) substrates over a temperature range of 160-222/sup 0/C by a solid-state reaction between the substrates and the Pd overlayers. The parabolic rate equation was verified and rate constants showed Arrhenius behavior with an activation energy E/sub a/ = 1.06 eV and prefactor k/sub 0/ = 7 x 10/sup -4/ cm/sup 2//s. The low value of E/sub a/ suggests a short-circuit diffusion mechanism. It is reasonable to expect that impurities and microstructure may play important roles in the growth process. Impurity levels in the specimens were evaluated by analytic techniques suited to thin-film study: Rutherford backscattering spectrometry, secondary ion mass spectrometry, and Auger electron spectrometry. No impurities were present at concentrations approaching 1 at. %. Some O, C, and F were detected at the Pd/sub ...

1986-05-15

308

Integrated well-completion strategies with CHOPS to enhance heavy-oil production : a case study in Fula Oilfield  

Energy Technology Data Exchange (ETDEWEB)

Cold Heavy Oil Production with Sand (CHOPS) is an enhanced oil recovery method that induces sand production to form a network of wormholes that increase the porosity and permeability of a formation. Under proper conditions, CHOPS can improve formation flow characteristics. Integrated well completion strategies that were used to increase oil production at Fula oil field on the south flank of Mughad Basin in Sudan were described. Limited sand influx provided a means for effective sand control while eliminating the need for conventional sand control processes. Cold heavy oil production with limited sand influx requires optimized completion methods to stimulate sand production, thereby reducing oil flow resistance and prolonging the sand removal operation cycle. Completion tests were performed in terms of different formation conditions including perforating completion; perforating and full sand control completion by screen liner; and perforating and limited sand control completion by ...

2005-11-01

309

Evaluation of cobalt mobility in soils from the Nevada Test Site  

Energy Technology Data Exchange (ETDEWEB)

Nuclear testing at and around the Nevada Test Site (NTS) resulted in widespread contamination from transuranic and other radionuclides, as well as from other toxic inorganic and organic contaminants. The type of contamination, including spatial distribution and type of radionuclides present, depends on the type of testing performed. Remediation of the contaminated areas is currently under way. The optimum in situ or ex situ remediation technology depends on the degree of interaction between the particular radionuclide, or contaminant in general, and the soil matrix, among other factors. The objective of this project was to evaluate the sorption affinity of NTS soils for common non-transuranic radionuclides. The sorption of cobalt (Co) on soils from two different areas of the NTS, namely the Little Feller and Cabriolet event sites, was studied. Experiments were conducted as a function of pH, solid concentration, total Co concentration, ionic strength, and particle ...

1996-09-01

310

Decontamination of LRW of low and intermediate level of activity with a new bio-sorbent mycoton  

International Nuclear Information System (INIS)

An absorption method of elimination of liquid radioactive wastes (LRW) of low and intermediate activity level by decreasing their contamination up to the level permitting their discharge into the environment is proposed in the paper. The LRW decontamination is accompanied with efficient compacting the resulting secondary solid wastes. The method is based on the use of a new very efficient, chitin containing natural fiber bio-sorbent, Mycoton, which is manufactured commercially in Ukraine. The chemical composition of the sorbent and its highly developed surface provide practically unrestricted opportunities for producing its modifications having any necessary absorption and operational characteristics. The effects of pH, the presence of various salts and complexing agents, as well as of some other factors to the distribution coefficients of the most important radionuclides have been carefully studied in experiments with Mycoton and its ...

2005-10-09

311

Combustion characteristics of fuel droplets with addition of nano and micron-sized aluminum particles  

Energy Technology Data Exchange (ETDEWEB)

The burning characteristics of fuel droplets containing nano and micron-sized aluminum particles were investigated. Particle size, surfactant concentration, and the type of base fluid were varied. In general, nanosuspensions can last much longer than micron suspensions, and ethanol-based fuels were found to achieve much better suspension than n-decane-based fuels. Five distinctive stages (preheating and ignition, classical combustion, microexplosion, surfactant flame, and aluminum droplet flame) were identified for an n-decane/nano-Al droplet, while only the first three stages occurred for an n-decane/micron-Al droplet. For the same solid loading rate and surfactant concentration, the disruption and microexplosion behavior of the micron suspension occurred later with much stronger intensity. The intense droplet fragmentation was accompanied by shell rupture, which caused a massive explosion of particles, and most of them were burned during this event. On the ...

2011-02-15

312

Advanced thermally stable jet fuels: Technical progress report, October 1994--December 1994  

Science.gov (United States)

There are five tasks within this project on thermally stable coal-based jet fuels. Progress on each of the tasks is described. Task 1, Investigation of the quantitative degradation chemistry of fuels, has 5 subtasks which are described: Literature review on thermal stability of jet fuels; Pyrolytic and catalytic reactions of potential endothermic fuels: cis- and trans-decalin; Use of site specific {sup 13}C-labeling to examine the thermal stressing of 1-phenylhexane: A case study for the determination of reaction kinetics in complex fuel mixtures versus model compound studies; Estimation of critical temperatures of jet fuels; and Surface effects on deposit formation in a flow reactor system. Under Task 2, Investigation of incipient deposition, the subtask reported is Uncertainty analysis on growth and deposition of particles during heating of coal-derived aviation gas turbine fuels; under Task 3, Characterization of solid gums, sediments, and ...

1995-02-01

314

Non-destructive Inspection of Surfaces  

International Science & Technology Center (ISTC)

Highly Precision Method for Nondestructive Analysis of Surfaces in a Subnanometer Depth Range

315

Petrographically deduced triassic climate for the Deep River Basin, eastern piedmont of North Carolina  

Energy Technology Data Exchange (ETDEWEB)

A petrographic comparison of Triassic, fluvial sandstones from the Deep River Basin in the eastern piedmont of North Carolina with nearby Holocene stream sands (1) indicates that he Triassic climate was more arid than today's and (2) distinguishes an eastern, more plutonic terrane from a western, more metamorphic source terrane. The paleoclimatic interpretation is based on differences in framework composition between modern and ancient sands of the same grain size, derived from the same rock type, transported similar distances and deposited in similar settings. The Triassic sandstones contain more lithic-fragments but less quartz than otherwise equivalent, modern sand in the Deep River Basin. Feldspar content is more complex, controlled by both source-rock composition and climate. Sand from the more plutonic terrane contains more feldspar and plutonic lithic-fragments than sand from the more metamorphic terrane, which contains more ...

1985-01-01

316

Occupational exposure to natural radionuclides due to mining activities in Ibadan, Southwestern Nigeria  

International Nuclear Information System (INIS)

The activity concentrations of potassium, uranium and thorium in minerals and soil samples from a mining site in Ibadan, Southwestern Nigeria were measured using gamma ray spectroscopy method. Effective dose per annum has been calculated from the activity concentrations of dominant gamma-emitting natural radionuclides, potassium, uranium and thorium. Samples collected include minerals (beryl, quartz and feldspar), soil samples from the mining pits, heaps and undisturbed land around the mining site. The activity concentrations of "4"0K, "2"3"8U and "2"3"2Th, respectively in Bq kg-1 in the mineral samples were as follows: 1985 #+-# 16, 4.8 #+-# 0.9 and 11.8 #+-# 5.8 for beryl sample, 115.1 #+-# 27.9, 5.0 #+-# 1.3 and 6.3 #+-# 5.0 for feldspar samples and 1421 #+-# 122, <4.8 and 20.1 #+-# 3.5 for quartz samples. For the soil samples, the mean activity concentrations of "4"0K, "2"3"8U and "2"3"2Th, respectively, were 314.2 #+-# 5.7, 27.7 #+-# ...

317

Depositional environment and petrographic and seismic interpretation of B Sandstone (a primary, waterflood, and enhanced recovery target), Olive Field, southwestern Mississippi  

Energy Technology Data Exchange (ETDEWEB)

Olive field is oil productive from a thin stratigraphically trapped sandstone within the Upper Cretaceous lower Tuscaloosa Formation. The discovery of Olive in 1981 led to renewed interest in the Mid-Dip Tuscaloosa Trend that continues today. Discovery and development was based on the correlation of the B sandstone to a mappable soft seismic event at a depth of 10,500 ft. The field was developed by 25 wells on 40-acre spacing. Olive has been waterflooded since 1983 and is a target for enhanced recovery using carbon dioxide. A total of 7.5 million stock tank bbl or approximately 75% of the original oil in place is estimated to be recoverable by conventional and enhanced recovery methods. The B sandstone was deposited by a northwest to southeast-flowing high-sinuosity meandering river system. Point bar, channel, and channel abandonment deposits are present. The point bar formed from the lateral migration of the river system from west to east, and channel abandonment is evident at the ...

1987-05-01

318

Chemical thermodynamics of silica: a critique on its geothermometer  

Energy Technology Data Exchange (ETDEWEB)

The chemical thermodynamic concepts used in the calculation of solubility data of silica (quartz) are presented taking into account the PVT characteristics of water. The temperature-dependence trends between the thermodynamically calculated and the experimental quartz solubility data are very similar, but the values are widely different at high temperatures. The experimental solubility, especially along the saturation curve at high temperature and thermodynamic data for silica need to be reevaluated in order to use silica chemistry to understand geological processes. There could exist a wide range of values for silica solubility at a specified temperature, depending upon the amount of water in the reaction vessel. Thus the silica contents in geothermal fluid, in general, cannot be used as a geothermometer to estimate the reservoir temperature. The derivation of a silica geothermometer needs an extra assumption about the total amount of water in ...

2000-06-01

319

Detritiation of solid waste using superheated steam  

International Nuclear Information System (INIS)

Full text: During JET operations, tritium contaminated waste is generated principally but not exclusively from 'intervention' work and from removing or replacing redundant items. It is essential for JET and for any future fusion plant to have available a route for managing each waste stream however large or small, both during operation and decommissioning of the plant. The long term outcome is to have for each tritiated waste stream from JET a route for its management leading to its eventual disposal or recycling (and thus to be available for similar waste streams which will be produced by ITER operations). Since several years SCK#centre dot#CEN has been developing techniques for the treatment of tritiated waste. Amongst them, technologies for water detritiation, for the treatment of tritiated organic liquids and for the decontamination of several types of solid tritiated waste. Our R and D focuses on the development of a system to decontaminate ...

2005-10-12

320

Two-Phase Stefan Problem with Interfacial Energy and Entropy.  

Science.gov (United States)

The classical Stefan theory for the melting of a solid or the freezing of a liquid is too simplistic to describe phenomena such as supercooling, in which a liquid supports temperatures below its freezing point, or superheating, the analog for solids, or d...

1985-01-01

321

Towards the solid-state rechargeable battery  

Energy Technology Data Exchange (ETDEWEB)

The Anglo-Danish programme of research on materials for advanced vehicular transport and other storage batteries is about to enter its fifth year. Here, the results of the work to date on solid electrolytes, electrode materials and cell design are reviewed and discussed as a systematic programme of cell testing gets underway.

1981-12-11

322

Solid-state 13C NMR spectroscopy of a 13C carbonyl-labeled polypeptide  

UK PubMed Central (United Kingdom)

High resolution structural elucidation of macromolecular structure by solid-state nuclear magnetic resonance requires the preparation of uniformly aligned samples that are isotopically labeled. In...Full Text Available

1992-06-01

323

Simulation of solid molecular hydrogen - a new twist to an old problem  

British Library Electronic Table of Contents (United Kingdom)

Solid molecular orthohydrogen exhibits orientational order at low temperatures. The orthohydrogen molecules, which are quadrupoles, order in the Pa3 structure. We have simulated this ordering, and explored the behaviour under dilution by spherical parahydrogen molecules.

2010-01-01

324

Quantum computing with solids  

Energy Technology Data Exchange (ETDEWEB)

Science and technology could be revolutionized by quantum computers, but building them from solid-state devices will not be easy. Robert W Keyes of IBM's research division outlines the challenges in scaling up the technology from lab experiments to practical devices. (U.K.)

2002-08-01

325

Process Waste Assessment for inorganic solid waste and empty containers <30 gallons  

Energy Technology Data Exchange (ETDEWEB)

This Process Waste Assessment was conducted to evaluate the two largest hazardous waste streams generated on-site at Sandia National Laboratory (SNL)/California -- ``Other Inorganic Solid Waste`` and ``Empty Containers <30 Gallons.``

1993-12-01

326

Prevention of guanine modification and chain cleavage during the solid phase synthesis of oligonucleotides using phosphoramidite derivatives.  

UK PubMed Central (United Kingdom)

Phosphoramidite reagents can phosphitylate guanine bases at the O6-position during solid phase synthesis and serious chain cleavage occurs if the base phosphitylation is not eliminated before the iodine/water...Full Text Available

1986-08-26

327

Pathological differential diagnosis of solid-pseudopapillary neoplasm and endocrine tumors of the pancreas  

UK PubMed Central (United Kingdom)

AIM: To investigate differential points of solid-pseudopapillary neoplasm (SPN) of the pancreas and pancreatic endocrine tumor (PET).METHODS: Ten cases of SPN and fourteen cases of PET were studied...Full Text Available

2010-02-28

328

Observations on the use of solid-phase-coupled antibodies in the radioimmunoassay of human placental lactogen  

UK PubMed Central (United Kingdom)

A detailed comparative assessment was made of the use of solid-phase-coupled antibodies in radioimmunoassay, by using an assay for human placental lactogen as a model system. The major advantages of...Full Text Available

1974-03-01

329

Membrane protein biosensing with plasmonic nanopore arrays and pore-spanning lipid membranes  

UK PubMed Central (United Kingdom)

Integration of solid-state biosensors and lipid bilayer membranes is important for membrane protein research and drug discovery. In these sensors, it is critical that the solid-state sensing...Full Text Available

2010-01-01

330

Inelastic x-ray scattering of dense solid oxygen: Evidence for intermolecular bonding  

UK PubMed Central (United Kingdom)

The detailing of the intermolecular interactions in dense solid oxygen is essential for an understanding of the rich polymorphism and remarkable properties of this element at high pressure. Synchrotron...Full Text Available

2008-08-19

331

Division of Materials Research Employment Opportunities for Program Directors--Dear Colleague Letter  

Science.gov (United States)

... materials science and engineering, condensed-matter or materials physics, solid-state or materials ... include materials theory, condensed-matter and materials physics, solid-state and materials ...

332

Cytological diagnosis of a rare case of solid pseudopapillary neoplasm of the pancreas  

UK PubMed Central (United Kingdom)

A 23-year-old woman presented to our hospital with nonspecific pain in the abdomen. She underwent radiological investigations, which revealed a solid and cystic mass in the tail end of the pancreas....Full Text Available

2010-01-01

333

Comparative Inhibitory Effects of Antigen and Antibody in the Staphylococcal Enterotoxin Solid-Phase Radioimmunoassay System  

UK PubMed Central (United Kingdom)

A solid-phase radioimmunoassay employing 125I-labeled enterotoxins and polystyrene tubes coated with specific antibody has been developed for assaying the relative concentrations of antibodies...Full Text Available

1975-06-01

334

Clinical Strategy for the Management of Solid Pseudopapillary Tumor of the Pancreas: Aggressive or Less?  

UK PubMed Central (United Kingdom)

Objective: To further delineate the clinicopathological and radiological features of solid pseudopapillary tumor (SPT) of the pancreas and summarize the surgical therapy strategy for this tumor. Methods:...Full Text Available

335

Aggressive behaviour of solid-pseudopapillary tumor of the pancreas in adults: A case report and review of the literature  

UK PubMed Central (United Kingdom)

Solid-pseudopapillary tumor (SPT) is a rare neoplasm of the pancreas that usually occurs in young females. It is generally considered a low-grade malignant tumor that can remain asymptomatic for several...Full Text Available

2008-02-14

336

Prediction of transmitted portal dose for in-vivo dosimetry by a superposition-convolution planning system  

International Nuclear Information System (INIS)

Full text: Verification of the dose delivered to a patient during radiotherapy is an important quality assurance procedure, however this is rarely performed due to the extra time involved. Electronic portal images (EPIs) are currently acquired at many centres during radiotherapy treatment for positioning verification. These could be utilised for dose verification provided 1) an accurate prediction of the dose transmitted through the patient to the EPID can be produced for the patients' radiotherapy beams, and, 2) the EPID image can be converted to an accurate measured dose. Ideally, the radiotherapy planning system (RTPS) would be used to produce the predicted dose as part of the planning procedure. The aim of this project is to investigate whether the convolution-superposition model of the Pinnacle RTPS can accurately calculate dose transmitted through a patient and deposited in a phantom at a large source to surface distance. The dose transmitted through a ...

2004-12-01

337

Thermal performance and design of a solid particle cavity receiver  

Energy Technology Data Exchange (ETDEWEB)

A model for energy transport in a solid particle cavity receiver is developed and applied to the design and analysis of a receiver for the Central Receiver Test Facility (CRTF), Albuquerque, New Mexico. The model gives thermal performance results - including particle temperatures, cavity efficiencies, and wall temperatures - which directly affect the economic and technical feasibility of a solid particle receiver. In addition, design criteria relevant to the configuration of a solid particle cavity receiver are developed. Results for CRTF indicate that at design conditions particle temperatures will exceed 1200/sup 0/K with cavity efficiencies on the order of 75%.

1985-04-01

338

Synchrotron Probes of Emergent Electronic States of Matter in Solids  

ScienceCinema

...of this article he quotes um i am told by my english ...

339

Process for retorting oil shale and the like  

Energy Technology Data Exchange (ETDEWEB)

The production of oil by retorting shale and other hydrocarbonaceous and lignocellulosic solid materials is facilitated by retorting in the presence of steam and acetic acid.

1983-08-02

340

PowerPoint Presentation  

Wastenet

facilities, building hygienic latrines and introducing regular solid waste collection systems . These methods are constantly being developed and

341

Passivation-free solid state battery  

Energy Technology Data Exchange (ETDEWEB)

This invention pertains to passivation-free solid-state rechargeable batteries composed of Li.sub.4 Ti.sub.5 O.sub.12 anode, a solid polymer electrolyte and a high voltage cathode. The solid polymer electrolyte comprises a polymer host, such as polyacrylonitrile, poly(vinyl chloride), poly(vinyl sulfone), and poly(vinylidene fluoride), plasticized by a solution of a Li salt in an organic solvent. The high voltage cathode includes LiMn.sub.2 O.sub.4, LiCoO.sub.2, LiNiO.sub.2 and LiV.sub.2 O.sub.5 and their derivatives.

1998-01-01

342

Passivation-free solid state battery  

Energy Technology Data Exchange (ETDEWEB)

This invention pertains to passivation-free solid-state rechargeable batteries composed of Li{sub 4}Ti{sub 5}O{sub 12} anode, a solid polymer electrolyte and a high voltage cathode. The solid polymer electrolyte comprises a polymer host, such as polyacrylonitrile, poly(vinyl chloride), poly(vinyl sulfone), and poly(vinylidene fluoride), plasticized by a solution of a Li salt in an organic solvent. The high voltage cathode includes LiMn{sub 2}O{sub 4}, LiCoO{sub 2}, LiNiO{sub 2} and LiV{sub 2}O{sub 5} and their derivatives. 5 figs.

1998-06-16

343

Particle-Sizing System for Scanning Electron Microscope ...  

Science.gov (United States)

... THESIS PARTICLE-SIZING SYSTEM FOR SCANNING ELECTRON MICROSCOPE IMAGES OF SOLID-PROPELLANT COMBUSTION EXHAUST ...

1991-03-01

345

Electron Beam and Gamma Radiolysis of Solid-State Metoclopramide  

British Library Electronic Table of Contents (United Kingdom)

Purpose Study the radiolysis of solid-state metoclopramide hydrochloride at various absorbed doses. Elucidate the structure of the degradation products to gain information on the radiolysis mechanisms. Methods Solid-state metoclopramide samples were irradiated at several doses with gamma rays and high-energy electrons to evaluate the influence of the dose rate. High-performance liquid chromatography with a diode array detector was used to measure the chemical potency as a function of the absorbed dose and to quantify the degradation products. The characterization of degradation products was performed by liquid chromatography/atmospheric pressure chemical ionization/tandem mass spectrometry. Results The degradation of solid-state metoclopramide after irradiation was negligible. No qualitati...

2006-01-01

347

Autogenous electrolyte, non-pyrolytically produced solid capacitor structure  

Energy Technology Data Exchange (ETDEWEB)

A solid electrolytic capacitor having a solid electrolyte comprising manganese dioxide dispersed in an aromatic polyamide capable of further cure to form polyimide linkages, the solid electrolyte being disposed between a first electrode made of valve metal covered by an anodic oxide film and a second electrode opposite the first electrode. The electrolyte autogenously produces water, oxygen, and hydroxyl groups which act as healing substances and is not itself produced pyrolytically. Reduction of the manganese dioxide and the water molecules released by formation of imide linkages result in substantially improved self-healing of anodic dielectric layer defects.

1998-01-01

348

A NEW FORM OF SOLID STATE SOLAR GENERATOR  

Science.gov (United States)

... nent to the design and construction of metal-semiconductor solar cells, in that both the photovoltage and the efficiency of metal-semiconductor cells ...

1962-01-01

349

Spontaneous radiation emission during penetration of ions in solids  

International Nuclear Information System (INIS)

In this work, the principal continuum radiative emission processes, which occur during the penetration of ions in solids or gases, are resumed. The characteristics of the following processes are discussed: secondary electron bremsstrahlung (SEB), atomic bremsstrahlung (AB), and internuclear bremsstrahlung (INB). Recent advances of the ion channeling effects in crystal solids on the spontaneous radiative spectra are exposed. (A.C.A.S.).

1988-09-25

350

Resources | Environment Knowledge Hub  

Wastenet

... MUNICIPAL SOLID WASTES (MANAGEMENT AND HANDLING) RULES, 2000 Plastic Bag ban in Dhaka City, Bangladesh Private Sector Participation in Municipal Solid Waste Management SKAT 2000 TECHNICAL GUIDELINES ON MUNICIPAL SOLID WASTE MANAGEMENT Hazardous Waste Management Unit, Environmental Pollution Control Division, Central Environmental Authority, Sri Lanka 2004 Subregional ...

351

Pharmaceutics | Special Issue: Solid Dosage Forms  

Wastenet

...Pharmaceutics | Special Issue: Solid Dosage Forms LoginRegister mdpi.com Journals A-Z For Authors About Open Access Policy Title / Keyword Journal all Administrative Sciences Agriculture ...Establishing Differences from Adults Recent Developments and Future Perspectives in Dissolution Testing Solid Dosage Forms The 1st Electronic Conference on Pharmaceutical Science The Progress on Pharmaceutics ... 1 (2009) Special Issue \\

352

Peculiarities of #beta#-solid solution decomposition in (#alpha#+#beta#) titanium alloy at low temperature  

International Nuclear Information System (INIS)

The physical methods were used to study the decomposition of a metastable #beta#-solid solution in the VT22 two-phase titanium alloy. It is shown that the martensitic #beta# #-># #alpha#'' transformation in doped-element depleted microvolumes of the #beta#-solid solution are dominanted and the long-time multistage decomposition through a number of intermediate states in others.

353

ON THE POSSIBILITY OF ENRICHMENT AND DIFFERENTIATION IN GAS GIANTS DURING BIRTH BY DISK INSTABILITY  

International Nuclear Information System (INIS)

We investigate the coupling between rock-size solids and gas during the formation of gas giant planets by disk fragmentation in the outer regions of massive disks. In this study, we use three-dimensional radiative hydrodynamic simulations and model solids as a spatial distribution of particles. We assume that half of the total solid fraction is in small grains and half in large solids. The former are perfectly entrained with the gas and set the opacity in the disk, while the latter are allowed to respond to gas drag forces, with the back reaction on the gas taken into account. To explore the maximum effects of gas-solid interactions, we first consider 10 cm size particles. We then compare these results to a simulation with 1 km size particles, which explores the low-drag regime. We show that (1) disk instability planets have the potential to form large cores due to aerodynamic ...

2010-11-20

354

Microwave Oven for the Rapid Determination of Total Solids Content of Natural Rubber Latex  

British Library Electronic Table of Contents (United Kingdom)

The suitability of using the microwave oven for the rapid determination of total solids content (TSC) of natural rubber latex has been established over a broad range of dry rubber content (DRC). The total solids content values obtained by the microwave oven method are compared with the values obtained by heating in a conventional convection oven. Heating in a microwave oven is advantageous as the measurement time could be reduced considerably.

2008-01-01

355

GS1 - radiological protection objectives for the disposal of solid radioactive wastes  

Energy Technology Data Exchange (ETDEWEB)

A summary is given of the 1983 NRPB-GS1 Report on the 'Radiological protection objectives for the disposal of solid radioactive wastes'. The two principal difficulties in applying the ICRP system of dose limitation to some solid waste disposal methods are outlined. Despite these difficulties three radiological protection objectives for waste disposal were recommended based on the same fundamental principle as ICRP recommendations.

1984-01-01

356

Decomposition of metastable solid solution in #beta#-titanium alloy  

International Nuclear Information System (INIS)

Peculiarities of metastable #beta#-solid solution decmposition in titanium alloy VT30 in the process of isothermal ageing in the range 500-650 deg C are investigated. Using the methods of transmittion electron microscopy, X-ray diffraction analysis, etc., it is shown that in the case of alloy quenching from the temperature below the point of complete polymorphous transformation (T_t_._t_.), as well as after warm rolling the course of subsequent decomposition of solid solution can be consierably complicated.

357

Analysis of stability of semiconductor 5-component solid solutions of A"3B"5 compounds  

International Nuclear Information System (INIS)

With the use of the regular solutions model the expressions have been derived for calculation of boundaries of spinodal decomposition region as applied to five-component solid solutions of A"3B"5 compounds. The evaluation has been made of fields of stability for Al_x__1Ga_x__2In_1_-_x__1_-_x__2PyAs_1_-_y solid solution.

358

Hydrogen storage in nano-structured carbon materials  

Energy Technology Data Exchange (ETDEWEB)

Full text of publication follows: Energy and environment are two major concerns in our modern society due to the coming shortage in fossil energy sources and the growing of greenhouse gas emissions. The challenge for the coming years is to discover new energy resources and to develop devices that are compatible with a sustainable development and generate few (or zero) emission. One of these devices is the fuel cell feed by hydrogen, whose application fields are very large. In particular, the proton exchange membrane fuel cell (PEMFC) is the most realistic device for automotive application. However, hydrogen storage remains one of the most important challenges regarding its development. Although different techniques are available for storing hydrogen, no ideal solution has been found yet. Compression needs elaborated tanks in shape for supporting high pressures, liquefaction requires an expensive hydrogen cooling and adapted tanks. Chemical storage by hydrides imposes heavy devices. A ...

2005-07-01

359

Hydrogen storage in nano-structured carbon materials  

Energy Technology Data Exchange (ETDEWEB)

Full text of publication follows: Energy and environment are two major concerns in our modern society due to the coming shortage in fossil energy sources and the growing of greenhouse gas emissions. The challenge for the coming years is to discover new energy resources and to develop devices that are compatible with a sustainable development and generate few (or zero) emission. One of these devices is the fuel cell feed by hydrogen, whose application fields are very large. In particular, the proton exchange membrane fuel cell (PEMFC) is the most realistic device for automotive application. However, hydrogen storage remains one of the most important challenges regarding its development. Although different techniques are available for storing hydrogen, no ideal solution has been found yet. Compression needs elaborated tanks in shape for supporting high pressures, liquefaction requires an expensive hydrogen cooling and adapted tanks. Chemical storage by hydrides imposes heavy devices. A ...

2005-07-01

360

X-ray studies of solid n-H/sub 2/  

Energy Technology Data Exchange (ETDEWEB)

Results of X-ray investigations of solid normal hydrogen are presented. Temperature dependences of the lattice parameteps, molar volumes, linear and volume expansion coefficients in the 2K-Tsub(melt) temperature range are obtaiped. An essential n-H/sub 2/ expansion anisotropy in the premelting temperature region is pointed out. It is shown that the hexagonal lattice parameter ratios over the whole investigated temperature range is considerably higher than for solid parahydrogen. A considerable difference in thermal expansion of normal hydrogen and parahydrogen in the low temperature region is revealed. It is caused by contribuation of a rotational subsystem, increasing with the temperature decrease to crystal expansion. A detailed analysis of solid n-H/sub 2/ thermodynamic properties is conducted. The data testifying to the presence of isomorphous phase transformation in the solid n-H/sub 2/ in the ...

1983-08-01

361

Theory of NMR multiple echoes in solid hydrogen  

Energy Technology Data Exchange (ETDEWEB)

We have examined the theory of NMR multiple echoes developed for solid {sup 3}He to determine whether multiple echoes could be observed in solid hydrogen. We were particularly interested in the possibility of testing for low frequency quantum tunneling motions in solid hydrogen by the observation of multiple echoes. We find that for easily accessible nuclear spin polarizations, P > 12%, multiple echoes would be observed for HD impurities in solid parahydrogen if motional narrowing is effective in increasing the HD nuclear spin-spin relaxation time T{sub 2} to the order of 1 msec. These values for T{sub 2}, which have been observed for HD impurity concentrations of the order of 1%, are larger than the calculated rigid lattice values and can be attributed to quantum tunneling at frequencies of the order of 1kHz.

1995-11-01

362

Solid suspension in stirred tanks: UVP measurements and CFD simulations  

British Library Electronic Table of Contents (United Kingdom)

Abstract Suspension of solids in stirred reactor is widely used for catalytic reactions, dissolution, etc. Quality of solid suspension is an important parameter required for the reliable design, optimum performance, and scale up of the system. Quality of suspension depends on local characteristics of solid velocity and hold up profiles. The present work was focused on investigating quality of solid suspension using ultrasound velocity profiler (UVP) measurements and CFD simulations. The slip velocity measurements carried out with UVP were used to evaluate different drag correlations used in CFD simulations. Results discussed in this work would be useful for extending the applications of CFD models for simulating large stirred slurry reactors.

2011-01-01

363

Self-inhibited rate in gas-solid noncatalytic reactions. The shrinking core model  

Energy Technology Data Exchange (ETDEWEB)

The shrinking core model is examined for gas-solid noncatalytic reactions with a self-inhibited rate form and it is shown that multiple reaction pathways are possible for solid particles reacted under identical conditions. The observed reaction rate can have up to two discontinuities (jumps) during reaction for particles of spherical and cylindrical shape. The geometric instability analysis reveals that the reaction interface is stable under a very limited set of conditions only for solid particles of slab geometry. For a sphere or cylinder at large Biot numbers the reaction interface is always potentially unstable. This model provides a plausible explanation for gas-solid reactions which exhibit erratic shrinking core behavior.

1984-02-01

364

Partial wave expansion of ion-atom elastic scattering in solids  

International Nuclear Information System (INIS)

Elastic scattering cross sections of keV protons in solids (Z=3-82) are calculated using the partial wave expansion technique and the ''muffin-tin'' bound-atom potential. The differential cross sections for small scattering angles of less than 10deg are smaller than those with the Ziegler-Biersack-Littmark potential at all energies and for all solids, although, for larger angles, the two cross sections agree with each other. The mean free paths of the protons in the solids, obtained from the total cross sections, decrease very slowly with decreasing energy. Furthermore, at low energies they approach half the nearest-neighbor distance, which is taken as the radius of the augmented plane wave sphere in the muffin-tin model of crystalline solids. (orig.).

365

On the solid-fluid transition zone in welding analysis  

Energy Technology Data Exchange (ETDEWEB)

Equilibrium and energy equations have been developed in describing the solid-fluid transition zone during the melting and solidification of the binary alloys. Due to the existence of the transition region exhibited both solid and fluid phases at the same material point from continuum point of view, mixture theory was utilized to analyze the region. Unlike the Stefan problem, the latent heat due to the phase change appears as a source term in the heat equation. The molten fluid is treated as a thermoviscous and incompressible fluid, whereas the solid is thermoviscoplastic described by the Bodner-Partom/Walker type of constitutive equations. Thermal mechanical behaviors of the solid and the fluid phases are determined separately because of insignificant mechanical interactions between them. Volume fractions of the phases are obtained according to the equilibrium phase diagram. The simulation process of ...

1993-01-01

366

Infrared spectroscopy of rovibrational transitions of methyl radicals (CH3, CD3) in solid parahydrogen  

British Library Electronic Table of Contents (United Kingdom)

The n3 and n4 vibrational transitions of CH3 and CD3 isolated in solid parahydrogen were studied by high-resolution infrared spectroscopy. The radicals were produced by in situ UV photolysis of methyl iodides trapped in solid parahydrogen. The observed spectra showed clear rotational fine structures, which were subjected to further splitting due to the electrostatic field of solid parahydrogen. The molecular constants and crystal field parameters of the radicals in solid parahydrogen were determined by analyzing the spectral structures of the n3 and n4 transitions of CD3 by the crystal field theory. The rotational constants of the CD3 radical were found to be only a few percent smaller than those in the gas phase. The determined crystal field parameters indicated significant quantum effect...

2011-01-01

367

Possible global environmental impacts of solid waste practices  

Energy Technology Data Exchange (ETDEWEB)

Pollutants resulting from the management of solid waste have been shown to affect the air, land, oceans, and waterways. In addition, solid wastes have other, more indirect impacts such as reduction in feedstocks of natural resources, because useful materials are disposed of rather than recycled. The objective of this study is to evaluate solid waste management practices that have negative implications on the global environment and develop recommendations for reducing such impacts. Recommendations identifying needed changes are identified that will reduce global impacts of solid waste practices in the future. The scope of this study includes the range of non-hazardous solid wastes produced within our society, including municipal solid waste (MSW) and industrial solid waste (ISW), as well as industry-specific wastes from activities such as ...

1994-09-01

368

Unusual Recharge Processes near Arroyos of the Rio Grande Aquifer, El Paso/Juarez Area  

Science.gov (United States)

The twin-cities of El Paso and Juarez share the water resources of the Hueco Bolson aquifer and overlying Rio Grande aquifer. Both aquifers span the international border between Mexico and the United States. Salinity in the Rio Grande aquifer varies widely, some parts of the shallow aquifer containing less than 1,000 mg/L total dissolved solids (TDS), other parts of the aquifer exceeding 5,000 mg/L TDS. One sizable part of the "Lower Valley" area, approximately 45 km below El Paso contains very dilute water near the outer edge of the floodplain. Historically it had been thought that the dilute waters in this location were derived from recharge from arroyos that drained proximal parts of the Hueco Bolson. Instead, our hydrogen and oxygen isotope data and carbon-14 data indicate that these dilute waters were derived from pre-dam infiltration of the Rio Grande. Relatively light and slightly evaporated pre-dam waters (-11.5 del O18) at the arroyos are also ...

2005-12-01

369

Three-phase flow in heterogeneous wettability porous media; Deplacements triphasiques en milieux poreux de mouillabilite heterogene  

Energy Technology Data Exchange (ETDEWEB)

Better understanding and modelling of three-phase flow through porous media is of great interest, especially for improved oil recovery methods such as gas injection processes. Early theoretical and experimental studies have already demonstrated that the wettability characteristics of the solid surface and the spreading characteristics of the fluid system hold the key roles. This observation is confirmed by our theoretical results using DLP theory on the stability and the thickness of static oil films. In most of the works related to three-phase flow processes, homogeneous wettability is assumed. There exist only a few studies demonstrating the tremendous impact of the wettability heterogeneities on gas injection. The objective of the present work is twofold: to demonstrate the effect of small scale wettability heterogeneities on gas injection efficiency, and to develop a tool to predict this impact for various patterns and spatial ...

1998-11-26

370

The role of oxygen diffusion in the release of technetium from reducing cementitious waste forms  

Energy Technology Data Exchange (ETDEWEB)

Cementitious materials provide an ideal geochemical environment (e.g., high pH pore fluids and large surface areas for sorption) for immobilizing nuclear waste. The inclusion of reducing agents, such as blast furnace slag (BFS) can immobilize radionuclides by forming of solid sulfide phases. Thermodynamic calculations using the MINTEQ geochemical computer code indicate the elemental sulfur present in BPS reacts with the highly mobile pertechnetate anion (TcO{sub 4}{sup -}) anion to form an insoluble technetium sulfide phase (Tc{sub 2}S{sub 7(s)}). Initially, the waste form very effectively immobilizes technetium. However, as oxygen diffuses into the waste form, an outer zone of oxidized concrete and a shrinking core of reduced intact concrete develops. Oxidation of sulfur in the outer zone results in increased technetium concentrations in the pore fluid because Tc{sub 2}S{sub 7(a)} oxidizes to the mobile TcO{sub 4}{sup -} anion. The TcO{sub ...

1993-12-31

371

T-HEMP3D, 3-D Time-Dependent Elastic Plastic Flow  

International Nuclear Information System (INIS)

1 - Description of program or function: T-HEMP3D (Transportable HEMP3D) is a derivative of the STEALTH three-dimensional thermodynamics code developed by Science Applications, Inc. Changes were made primarily in three areas: material specification, coordinate generation, and the addition of sliding surface boundary conditions. STEALTH itself is based entirely on the HEMP3D code written at LLNL. HEMP3D solves problems in solid mechanics involving dynamic plasticity and time-dependent material behavior and problems in gas dynamics. 2 - Method of solution: The equations of motion, conservation equations, and constitutive relations for stresses, strains, hydrostatic pressure, the von Mises yield condition, and artificial viscosity are solved by finite difference methods following the format of the HEMP code (NESC Abstract 775). The physical object is divided into zones defined by 8 grid points. The grid (i,j,k) moves with the material, and the mass ...

372

State of the Art Laser Induced Breakdown Spectroscopy  

International Nuclear Information System (INIS)

Methods currently being used or developed for the elemental analysis of materials are chemical analysis, non-destructive inspection and calorimetry. The chemical analysis, which removes high-level radioactive elements through chemical treatments and then performs the quantitative analysis using the ICP-MS(Inductively Coupled Plasma - Mass Spectrometer) or the ID-MS(Isotope Dilution Mass Spectrometer), is recognized the most accurate. However, it requires a long, complex pre-treatment process in which a mass spectrometer could be contaminated. To solve this problem, a new method, which can be performed with high-level radioactivity and at high temperature, was desired. Such a method should also have the same accuracy as the chemical analysis, with a less possibility for instruments to be contaminated. In addition, as interests in the environment and the life quality are increased, a detailed analysis on the environmental impacts is also required. Satisfying all of the above-mentioned, ...

373

Simulation of char combustion according to shrinking particle and shrinking core model in circulating fluidized bed boilers; Simulation des Koksabbrandes nach dem Shrinking Particle- und Shrinking Core Modell in zirkulierenden Wirbelschichtfeuerungen  

Energy Technology Data Exchange (ETDEWEB)

The presented paper describes the formulation of the fractional mass balances which are used to calculate the concentration and size distribution of char in the balance cells of a circulating fluidized bed boiler. In case of using the shrinking core model additionally the distribution of conversion of the char particles is calculated. Basically two reaction models (a shrinking particle and a shrinking core model) are available to describe the combustion process. The model considers all essential physico/chemical phenomena (primary fragmentation, attrition, mass transfer to gas phase) which have to be taken into account for the description of the combustion process. The model is part of an overall simulation program for circulating fluidized bed boilers. This engineering simulator has been developed to return the main performance parameters of such systems like temperature along the furnace height, size distribution of balanced solid components, heat flows at the ...

1998-12-31

374

Self-consistent full-potential linearized-augmented-plane-wave local-density electronic-structure studies of magnetism and superconductivity in C15 compounds: ZrZn_2 and ZrV_2  

International Nuclear Information System (INIS)

The electronic structure and properties of the cubic Laves phase (C15) compounds ZrZn_2 and ZrV_2 have been determined using our all-electron full-potential linearized-augmented-plane-wave (FLAPW) method for bulk solids. The computations were performed in two stages: (i) self-consistent warped muffin tin and (ii) self-consistent full potential. Spin-orbit coupling was included after either stage. The effects of the inclusion of the nonspherical terms inside the muffin tins on the eigenvalues is found to be small (of order 1 mRy). However, due to the fact that some of the bands near the Fermi level are flat, this effect leads to a much higher value of the density of states at E/sub F/ in ZnZr_2. The most important difference between the materials ZrZn_2 and ZrV_2 is the position of the d bands derived from the Zr and V atoms. Consequently, these materials have completely different Fermi surfaces. We have investigated the magnetic properties of ...

375

Self-consistent full-potential linearized-augmented-plane-wave local-density electronic-structure studies of magnetism and superconductivity in C15 compounds: ZrZn/sub 2/ and ZrV/sub 2/  

Energy Technology Data Exchange (ETDEWEB)

The electronic structure and properties of the cubic Laves phase (C15) compounds ZrZn/sub 2/ and ZrV/sub 2/ have been determined using our all-electron full-potential linearized-augmented-plane-wave (FLAPW) method for bulk solids. The computations were performed in two stages: (i) self-consistent warped muffin tin and (ii) self-consistent full potential. Spin-orbit coupling was included after either stage. The effects of the inclusion of the nonspherical terms inside the muffin tins on the eigenvalues is found to be small (of order 1 mRy). However, due to the fact that some of the bands near the Fermi level are flat, this effect leads to a much higher value of the density of states at E/sub F/ in ZnZr/sub 2/. The most important difference between the materials ZrZn/sub 2/ and ZrV/sub 2/ is the position of the d bands derived from the Zr and V atoms. Consequently, these materials have completely different Fermi surfaces. We have investigated the ...

1988-03-01

376

Producing non-blast furnace coke from brown coals of the Kansk-Achinsk coalfield  

Science.gov (United States)

The production of any form of coke is determined mainly by the raw material costs. Consequently for the production of special coke, of which the demand is satisfied at the present time by small size fractions of beehive coke or even blast furnace coke, it is necessary to use not only the plentiful coals but also the brown coals of the Kansk-Achinsk coalfield where mining is being expanded. The large reserves of the Kansk-Achinsk brown coals and the favorable geological conditions for recovery by the open-cast method make it possible to increase coal extraction from 31.6.10/sup 6/ tons in 1978 to 350.10/sup 6/ tons/yr in the next 15 to 20 years. In order to explain the high reactivity of heat treated brown coals we shall compare their properties with bituminous coal coke. During the heating of bituminous coals (with a high voltatile matter content) they are able to be weakly fused, to form a structure of coke whose pores are smooth because the coal is partially transformed into a ...

1981-01-01

377

Physical Modelling of Axisymmetric Turbulent Impinging Jets as used within the Nuclear Industry for Mobilisation of Sludges  

Energy Technology Data Exchange (ETDEWEB)

The impingement of a fluid jet onto a surface has broad applications across many industries. Within the UK nuclear industry, during the final stages of fuel reprocessing, impinging fluid jets are utilised to mobilise settled sludge material within storage tanks and ponds in preparation for transfer and ultimate immobilisation through vitrification. Despite the extensive applications of impinging jets within the nuclear and other industries, the study of two-phase, solid loaded, impinging jets is limited, and generally restricted to computational modelling. Surprisingly, very little fundamental understanding of the turbulence structure within such fluid flows through experimental investigation is found within the literature. The physical modelling of impinging jet systems could successfully serve to aid computer model validation, determine operating requirements, evaluate plant throughput requirements, optimise process operations and support ...

2008-07-01

378

Particle emission from low energy nuclear reactions in solids. Preliminary results  

Energy Technology Data Exchange (ETDEWEB)

TiH{sub 2} and TiD{sub 2} thick targets were bombarded with 100 to 200 keV protons or deuterons. Evidence for nuclear reactions was obtained by means of a surface barrier particle detector. Deuteron irradiation of TiD{sub 2} produced these observations: copious {approx}2.5 MeV neutrons and {approx}3 MeV protons from direct D-D reactions; gamma rays from p,{gamma} and n,{gamma} reactions; {approx}14 MeV protons from the secondary d({sup 3}He, p){alpha} reaction; and a signal between {approx}6-12 MeV that Kasagi et al. has tentatively identified as protons from the fusion of three deuterium nuclei. However, this signal has in it a strong interference signal from either neutrons or gamma rays that directly deposit energy in the detector. This interference spectra was measured by placing a thick absorber in front of the detector that stops up to 20 MeV protons, but not gamma rays or neutrons. More experiments must be done before we can confirm or deny the existence in ...

2000-07-01

379

Oxidation and adsorption of Co(II) EDTA{sup 2-} complexes in subsurface materials with iron and manganese oxide grain coatings  

Science.gov (United States)

Batch interaction experiments were performed under aerobic conditions to characterize the adsorption behavior and valence speciation of CoEDTA complexes (equimolar at 10{sup -5} mol/L) in a series of Pliocene subsurface sediments containing various amounts of Fe and Mn oxides. The experiments were performed in 0.003 mol/L Ca(ClO{sub 4}){sub 2} with a solids concentration of 500 g/L at variable pH (4-9) and at the natural pH of the sediments (pH = 8.3). Three of these subaerial sediments (Ringold 1, 2, 3) contained significant quantities of extractable Fe and Mn, while the fourth (Ringold 4) was virtually devoid of sesquioxide precipates. Microscopic and mineralogic analyses of the most heavily encrusted material (Ringold 2) showed that the oxides existed as intergrain cements and contained crystalline goethite and rancieite/todorokite. Adsorption on a synthetic analog sorbent (0.6 mass% ferrihydrite-coated sand) over a range in pH showed that, while both Co(II) ...

1995-11-01

380

On the anatomy of the adsorption heat versus loading as a function of temperature and adsorbate for a graphitic surface.  

Science.gov (United States)

In this paper we review and classify the various patterns of isosteric heat versus loading for adsorption of gases on graphitised thermal carbon black at temperatures ranging from below the 3D triple point to temperatures above it, but less than the 3D critical point. We have identified the features of heat curve and highlighted the microscopic origin of these features. The patterns vary with temperature and with the relative strength of the fluid-fluid interaction and solid-fluid interaction. For simple adsorptives (by simple we meant there is no strong association between fluid particles), the heat curve is typified by fluid-fluid attraction and layering phenomena. For adsorptives showing strong association such as water, ammonia and methanol, the heat curve essentially begins below the condensation heat and then approaches it as loading is increased. This is mainly due to the strong hydrogen bonding in these fluids. A third group includes adsorptives such as ...

2008-05-24

381

LWR pressure-vessel irradiation surveillance dosimetry. Quarterly progress report, October 1981-December 1981  

Energy Technology Data Exchange (ETDEWEB)

A technique involving shifting of core fuel loadings was investigated as a method for reducing the neutron flux at points of high damage accumulation in the pressure vessel wall of a light water reactor. Calculations were run for six types of commercial generic PWR. Information is provided on the progress being made to develop and apply the Solid State Track Recorder (SSTR) method for in-situ in- and ex-vessel measurements of neutron exposure parameter values, such as fluence (E > 1.0 MeV) and dpa in iron. A new technique of quantitative track counting, the Buffon needle method, is advanced. It is based on random sampling of the SSTR surface. A desensitized etching technique was developed that resulted in an excellent differential energy response for alpha particles in the 3- to 14-MeV energy range. The optical efficiency of Muscovite mica for manual fission track counting is being redetermined to form a data base for comparison with ...

1982-10-01

382

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

Energy Technology Data Exchange (ETDEWEB)

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

1987-11-01

383

Development of a solution method for the differential equations arising in the biosphere module of the BNFL's suite of codes MONDRIAN  

International Nuclear Information System (INIS)

British Nuclear Fuels plc owns and operates the near-surface Drigg disposal facility for low level radioactive waste. The long-term performance of the site is modelled by a suite of computer codes called MONDRIAN. One of the modules of MONDRIAN deals with the transport of radionuclides through the environment, and this paper reports on the current status of this module (BIOS). We derive the basic set of working equations from first principles and show clearly how the approximate nature of the final equations is arrived at. This is done by an averaging process leading to compartments, in and out of which radionuclides, solids and water can flow. The equations allow radioactive decay chains and an arbitrary number of compartments. There is also the facility to deal with changes in the rate coefficients, thereby simulating different environmental states. It is also possible to include the creation of new compartments arising as a consequence of ...

2002-06-01

384

DIVALENT ION EXCHANGE WITH ALKALI  

Energy Technology Data Exchange (ETDEWEB)

Exchange of hardness ions is important in enhanced oil recovery with chemical additives. In both micellar-polymer and caustic flooding processes, multivalent ions released from rock surfaces can interact with anionic surfactants, rendering them preferentially oil soluble and/or insoluble in water. Because hardness cations are sparingly soluble and precipitate in alkaline solutions, such solutions may be more efficient as surfactant flood preflushes than are softened brines. Multivalent ion precipitation may also occur in alkaline waterflooding. To permit design of such processes, this paper presents a chromatographic theory for simultaneous ion exchange with precipitation of divalent ions. Theoretical effluent histories and concentration profiles are presented for the cases of finite pulses and continuous injection of hydroxide ions into linear cores. Complete capture of the insoluble salt particles is assumed. Results are given for the case of instantaneous ...

1980-05-01

385

Coupled modeling of non-isothermal multiphase flow, solutetransport and reactive chemistry in porous and fractured media: 1. ModelDevelopment and Validation  

Energy Technology Data Exchange (ETDEWEB)

Coupled modeling of subsurface multiphase fluid and heat flow, solute transport and chemical reactions can be used for the assessment of acid mine drainage remediation, mineral deposition, waste disposal sites, hydrothermal convection, contaminant transport, and groundwater quality. Here they present a numerical simulation model, TOUGHREACT, which considers non-isothermal multi-component chemical transport in both liquid and gas phases. A wide range of subsurface thermo-physical-chemical processes is considered. The model can be applied to one-, two- or three-dimensional porous and fractured media with physical and chemical heterogeneity. The model can accommodate any number of chemical species present in liquid, gas and solid phases. A variety of equilibrium chemical reactions is considered, such as aqueous complexation, gas dissolution/exsolution, cation exchange, and surface complexation. Mineral dissolution/precipitation can proceed either ...

1998-09-01

386

Comparison of Ceramic, Metal and Polymer Crevice Formers on the Crevice Corrosopn Behavior of Ni-CR-Mo Alloy C22  

Energy Technology Data Exchange (ETDEWEB)

A necessary condition for crevice corrosion is that a crevice former create a sufficiently tight, restricted geometry on the metal surface to support the development of critical crevice chemistry. Crevice corrosion is affected by the crevice geometry (tightness) and the properties of the crevice former. The objective of this study is to determine the effect of the crevice former material on the evolution of localized corrosion-damage. A standard crevice corrosion test method is modified by (a) the use of ceramic, metal or polymer materials as the crevice former and (b) the variation of size and shape of the crevice. This study focuses on the post initiation stage of crevice corrosion and addresses factors that may limit the initiation of localized corrosion and also slow or stop the continued propagation of corrosion. Controlled crevice corrosion tests are performed under aggressive, accelerated conditions on Ni-Cr-Mo alloy C-22 and other alloys for comparison. ...

2006-05-08

387

Ceramics based on SmCoO{sub 3-{delta}} prepared by combustion synthesis as catalysts in hydrocarbon partial oxidation  

Energy Technology Data Exchange (ETDEWEB)

Samarium cobaltite ceramic perovskites, with and without platinum particles dispersion, are possible candidates as electrode for electrochemical conversion of hydrocarbon and for intermediate temperature solid oxide fuel cells (ITSOFC). In this work, samarium cobaltites were synthesized by the combustion method using cobalt, and samarium nitrates as cation precursors and urea as fuel. For containing-platinum compositions Pt (II) acetyl acetonate was also employed as precursor. The effect of Sr on the phase formation and its electrical behavior is also studied. Specific surface area (BET), SEM-EDX, TEM and XRD analysis are used to characterize the powders obtained. Powders were pressed into pellets and sintered in air in the temperature range of 1200 -1400 C. Electrical impedance spectroscopy studies (EIS) are performed on sintered samples. The as-prepared powders showed an amorphous structure and by TEM a very small particle size ...

2002-07-01

388

Assessment Of Heavy Metal Contamination Of Arable Soils In Central Bekaa Plain, Lebanon  

International Nuclear Information System (INIS)

The study area is located in the Bekaa plain of Lebanon totaling about 12753 ha. It lies between the eastern foothills of Mount Lebanon chain and expands across the Litani River towards the foothills of the eastern Anti-Lebanon Mountains. Its characteristics, i.e. natural terrain, climate and socio-economy, make it vulnerable especially due to soil pollution. This paper tries to identify the nature and level of soil pollution by heavy metals. Valley slopes represent a complex landform and lithology that contributed to the formation of different soil. Agriculture in the plain is being practiced mainly with cash, field crops and vegetables. Throughout the central part of the plain, groundwater table is abundant and relatively high (<1.0 m. locally) that multiplies the vulnerability of the soil-groundwater system. There are different sources of pollution, such as industrial (tanneries, batteries, leather manufacturing), solid and liquid wastes, and agricultural due ...

2004-12-04

389

Nanocrystal conversion chemistry: A unified and materials-general strategy for the template-based synthesis of nanocrystalline solids  

International Nuclear Information System (INIS)

The concept of nanocrystal conversion chemistry, which involves the use of pre-formed nanoparticles as templates for chemical transformation into derivative solids, has emerged as a powerful approach for designing the synthesis of complex nanocrystalline solids. The general strategy exploits established synthetic capabilities in simple nanocrystal systems and uses these nanocrystals as templates that help to define the composition, crystal structure, and morphology of product nanocrystals. This article highlights key examples of 'conversion chemistry' approaches to the synthesis of nanocrystalline solids using a variety of techniques, including galvanic replacement, diffusion, oxidation, and ion exchange. The discussion is organized according to classes of solids, highlighting the diverse target systems that are accessible using similar chemical concepts: metals, oxides, chalcogenides, phosphides, ...

2008-07-01

390

Carbon dioxide purification through two-stage combustion ENCAP. Final report; Koldioxidrening med tvaastegsforbranning ENCAP. Slutrapport  

Energy Technology Data Exchange (ETDEWEB)

Chemical-looping combustion (CLC), has previously been studied as a method for separating CO{sub 2} during combustion of gaseous fuels. In this project the possibility to apply this process for direct use of solid fuels has been investigated. The following has been accomplished: A 10 kW reactor system for CLC with solid fuels has been designed and built. Tests with solid fuel and metal oxid particles in a laboratory reactor show that it is possible to oxidize solid fuels with metal oxide particles in cyclic testing, thus giving proof of basic concept. They also show how the reaction rate is affected by temperature, steam concentration etc., and, most important of all, that the rates of reaction are realistic. Tests with metal oxide materials available at low costs have been successful. Chemical-looping combustion with solid fuels has a potential to achieve very low costs for ...

2006-06-15

392

Correlations between surface structure and catalytic activity/selectivity  

Energy Technology Data Exchange (ETDEWEB)

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

1990-11-01

393

Biological Surface-Active Substance  

International Science & Technology Center (ISTC)

Development of biological preparation with surfactant activity

394

Utilization of red mud in the manufacture of ceramic tiles  

Energy Technology Data Exchange (ETDEWEB)

Red mud, which is a pollutant residue from the extraction of alumina from bauxite ore, was utilized as an additive to a well blended mixture of three Egyptian clays, feldspar, quartz and grog. This was added in gradual proportions to study its effect on the vitrification properties of fired samples. Samples were moulded under a pressure of 20.7 MPa and fired at temperatures ranging from 950 C to 1100 C for soaking periods up to three hours. Compressive strength was determined as function of percent red mud added and firing temperature. A semi-exponential relation was established between strength and apparent porosity. 50 x 50 mm tiles containing 70% red mud addition and fired at 1100 C for one hour were tested. They were found to match the standards required for glazed wall tiles bodies. Tiles fired at 1100 C for 3 hours were compatible with the standards for glazed floor tiles. (orig.)

2002-07-01

395

Thermal expansion model for multiphase electronic packaging materials  

International Nuclear Information System (INIS)

Control of thermal expansion is often necessary in the design and selection of electronic packages. In some instances, it is desirable to have a coefficient of thermal expansion intermediate between values readily attainable with single or two phase materials. The addition of a third phase in the form of fillers, whiskers, or fibers can be used to attain intermediate expansions. To help design the thermal expansion of multiphase materials for specific applications, a closed form model has been developed that accurately predicts the effective elastic properties of isotropic filled materials and transversely isotropic lamina. Properties of filled matrix materials are used as inputs to the lamina model to obtain the composite elastic properties as a function of the volume fraction of each phase. Hybrid composites with two or more fiber types are easily handled with this model. This paper reports that results for glass, quartz, and Kevlar fibers with beta-eucryptite ...

396

Study of well logs from Cove Fort-Sulphurdale KGRA, Millard and Beaver Counties, Utah  

Energy Technology Data Exchange (ETDEWEB)

Union Oil Company drilled four geothermal test wells in the Cove Fort-Sulphurdale KGRA between 1975 and 1979. A fairly complete suite of well logs were recorded for the three deeper holes, and these data are presented as composite well log plots in this report. The composite well log plots have facilitated the interpretation of limestone, dolomite, sandstone, quartz-monzonite, serpentine, and volcanic lithologies and the identification of numerous fractures. This has been especially helpful because of the extensive lost circulaton zones and poor cuttings recovery. Intraformational flow was identified by a fluid migration-temperature tracer log at depth in CFSU 31-33. Well log crossplots were computed to assist in lithologic identification and the determination of physical properties for specific depth intervals in a given hole. The presence of hydrous minerals sometimes results in neutron porosity somewhat higher than the true nonfracture porosity, which is ...

1982-07-01

397

Shallow hydrothermal regime of the East Brawley and Glamis known geothermal resource areas, Salton Trough, California  

Energy Technology Data Exchange (ETDEWEB)

Thermal gradients and thermal conductivities were obtained in real time using an in situ heat-flow technique in 15 shallow (90 to 150 m) wells drilled between Brawley and Glamis in the Imperial Valley, Southern California. The in situ measurements were supplemented by follow-up conventional temperature logs in seven of the wells and by laboratory measurements of thermal conductivity on drill cuttings. The deltaic sedimentary material comprising the upper approx. 100 m of the Salton Trough generally is poorly sorted and high in quartz resulting in quite high thermal conductivities (averaging 2.0 Wm/sup -1/ K/sup -1/ as opposed to 1.2 to 1.7 for typical alluvium). A broad heat-flow anomaly with maximum of about 200 mWm/sup -2/ (approx. 5 HFU) is centered between Glamis and East Brawley and is superimposed on a regional heat-flow high in excess of 100 mWm/sup -2/ (> 2.5 HFU). The heat-flow high corresponds with a gravity maximum and partially with a minimum in ...

1981-01-01

398

Radiometric analysis of raw materials and end products in the Turkish ceramics industry  

International Nuclear Information System (INIS)

This study presents the findings of radiometric analysis carried out to determine the activity concentrations of natural radionuclides in raw materials (clay, kaolin, quartz, feldspar, dolomite, alumina, bauxite, zirconium minerals, red mud and frit) and end products (glazed ceramic wall and floor tiles) in the Turkish ceramics industry. Hundred forty-six samples were obtained from various manufacturers and suppliers throughout the country and analyzed using gamma-ray spectrometer with HPGe detectors. Radiological parameters such as radium equivalent activity, activity concentration index and alpha index were calculated to assess the radiological aspects of the use of the ceramic end products as decorative or covering materials in construction sector. Results obtained were examined in the light of the relevant national and international legislation and guidance and compared with the results of similar studies reported in different countries. The results suggest ...

2011-05-01

399

Influence of crystallization on the spectral features of nano-sized ferroelectric barium strontium titanate (Ba0.7Sr0.3Tio3) thin films  

British Library Electronic Table of Contents (United Kingdom)

Ferroelectric barium strontium titanate (Ba0.7Sr0.3TiO3)(BST) thin films have been prepared from barium 2-ethylhexanoate [Ba[CH3(CH2)3CH(C2H5)CO2]2], strontium 2-ethylhexanoate [Sr[CH3(CH2)3CH(C2H5)CO2]2] and titanium(IV) isopropoxide [TiOCH(CH3)2]4 precursors using a modified sol-gel technique. The precursor except [TiOCH(CH3)2]4 were synthesized in the laboratory. Transparent and crack-free films were fabricated on pre-cleaned quartz substrates by spin coating. The structural and optical properties of films annealed at different temperatures have been investigated. The as-fired films were found to be amorphous that crystallized to the tetragonal phase after annealing at 550degreeC for 1h in air. The lattice constants "a" and "c" were found to be 3.974A and 3.990A, respectively. The grain...

2008-01-01

400

Hydrodynamics of air-sand flow in a conical swirling fluidized bed: A comparative study between tangential and axial air entries  

British Library Electronic Table of Contents (United Kingdom)

Hydrodynamic regimes and characteristics of air-sand flow were studied in a cone-shape swirling fluidized bed for two types of air entry, or swirl generator: through a four-nozzle system (tangential entry) and using an annular-spiral air distributor (axial entry). Quartz sand of four particle sizes, 180-300, 300-500, 500-600 and 850-1180mm, was used as the bed material in experimental tests on a cold model of a conical swirling fluidized bed combustor. During each test run, the pressure drop across the bed (Dp) was measured versus superficial velocity at the lower bed basis (u) for three static bed heights (20, 30 and 40cm). Four regimes were found in the bed behavior for both swirl generators. The Dp-u diagrams were compared between tangential and axial air entries for different operating...

2009-01-01

401

Hydrodynamic studies of post dryout two-phase downflow in narrow channels  

Energy Technology Data Exchange (ETDEWEB)

An experimental study of the hydrodynamics of a narrow channel was performed in order to obtain the heat transfer mechanisms and influences contributing to the flow regime transition from inverted annular to inverted slug flows for post dryout downflow. The experimental series consisted of both adiabatic and diabatic visualization tests over a wide range of fluid and thermal parameters. The system inlet gas velocities ranged from 0 to 14 meters per second while the inlet fluid velocities ranged from 1 to 3 meters per second. Full extent visualization of the flow regime was possible due to a quartz tube in tube construction with a clear heating fluid. Constant temperature heating of the freon was accomplished at bulk fluid temperatures above the critical heat flux temperature. For each hydrodynamic flow condition, one to three minuets of VHS-video filming was performed to acquire both flow regime and break-up length data. In addition to this the flow field ...

1995-07-01

402

High precision, in situ oxygen isotope ratio measurements obtained from geological and extra-terrestrial materials using an Isolab 54 ion microprobe  

Energy Technology Data Exchange (ETDEWEB)

We have developed an ion probe technique for the in situ measurement of oxygen isotope ratios, {sup 18}O/{sup 16}O and {sup 17}O/{sup 16}O, with high spatial resolution in polished thin sections of silicate minerals. This technique allows the isotopic analysis of samples as small as picomoles of material which represents only 10{sup -7} of the sample size required by conventional fluorination oxygen isotope measurement methods and thus has wide application to the study of many terrestrial and extra-terrestrial samples that have heterogeneous oxygen isotope compositions on a scale of tens of micrometres. To illustrate the breadth of studies that are made possible by the ion probe, we report here oxygen isotope measurements from an authigenic quartz overgrowth obtained from the Penrith sandstone, UK, and measurements of magnetite grains from the Orgueil and Yamato 82162 carbonaceous chondrites which may be used to constrain possible formation mechanisms of the ...

1995-05-01

403

ESR dating of fault rocks  

Energy Technology Data Exchange (ETDEWEB)

Past movement on faults can be dated by measurement of the intensity of ESR signals in quartz. These signals are reset by local lattice deformation and local frictional heating on grain contacts at the time of fault movement. The ESR signals then grow back as a result of bombardment by ionizing radiation from surrounding rocks. The age is obtained from the ratio of the equivalent dose, needed to produce the observed signal, to the dose rate. Fine grains are more completely reset during faulting, and a plot of age vs. grain size shows a plateau for grains below critical size; these grains are presumed to have been completely zeroed by the last fault activity. We carried out ESR dating of fault rocks collected near the Gori nuclear reactor. Most of the ESR signals of fault rocks collected from the basement are saturated. This indicates that the last movement of the faults had occurred before the Quaternary period. However, ESR dates from the Oyong fault zone range ...

2003-02-15

404

Desorption of polycyclic aromatic hydrocarbons (PAH`s) from calcite and quartz sediments to seawater  

Energy Technology Data Exchange (ETDEWEB)

Polycyclic aromatic hydrocarbons (PAH`s) are ubiquitous hydrophobic organic pollutants in the marine environment. Many of the PAM`s are classified as possible carcinogens or mutagens, therefore they are of considerable concern to human and environmental health. The highest concentrations are found in coastal regions due to anthropogenic activities including oil spills, tanker operations, incomplete fossil fuel combustion and runoff. The sources and distribution of PAM`s in sediments are fairly well known, while the fate and transport of PAH`s in the marine environment are less known. Desorption is an important factor influencing the fate and transport of hydrophobic molecules at the seawater/sediment interface. The desorption of PAH`s from contaminated marine sediments to the water column/pore water affects the availability of the pollutant to biota. The sorption of PAH`s is determined in part by the organic carbon content of the sediments. The presence of dissolved organic carbon ...

1996-12-31

405

Degradation of materials under conditions of the sulphur-iodine thermochemical cycle  

Energy Technology Data Exchange (ETDEWEB)

The need for a hydrogen economy is driven by increasing fuel prices, depleting oil reserves and uncertainty over supplies, and concerns about global warming and environmental pollution. Alternative methods to portable energy sources such as fossil fuels are being developed that are more efficient and carbon-emission-neutral. A prospective method is to produce hydrogen as an energy carrier. This paper presented a study on the degradation of materials under conditions of the sulphur-iodine (SI) thermochemical cycle. The paper provided background information on the study and presented a schematic of the SI cycle. A literature review was presented along with materials selected, such as refractory metals, reactive metals, superalloys, glassy metals, ceramics, cermets, polymers, composites, and coatings. The experimental method was then described. A capsule method was developed to rapidly quantify the decomposition rate of the candidate materials under the target conditions of temperature, ...

2009-07-01

406

Conversion of char nitrogen to N2 under incomplete combustion conditions; Fukanzen nensho jokenka ni okeru char chuchisso no N2 eno tenka  

Energy Technology Data Exchange (ETDEWEB)

The effect of combustion conditions on conversion of char nitrogen to N2 was studied in the combustion experiment of char obtained by pyrolysis of coal. Char specimen was prepared by holding ZN coal of Chinese lignite in Ar atmosphere at 1123K for one hour. A batch scale quartz-made fluidized bed reactor was used for combustion experiment. After the specimen was fluidized in reaction gas, it was rapidly heated to start combustion reaction. CO, CO2 and N2 in produced gases were online measured by gas chromatography (GC). As the experimental result, under the incomplete combustion condition where a large amount of CO was produced by consuming almost all of O2, no NOx and N2O produced from char were found, and almost all of N-containing gas was N2. At the final stage of combustion, pyridinic-N disappeared completely, and pyrrolic-N decreased, while O-containing nitrogen complexes became a main component. It was thus suggested that O-containing nitrogen complexes are ...

1996-10-28

407

Co-production of hydrogen and carbon black from solar thermal methane splitting in a tubular reactor prototype  

British Library Electronic Table of Contents (United Kingdom)

This study addresses the solar thermal decomposition of natural gas for the co-production of hydrogen and carbon black (CB) as a high-value nano-material with the bonus of zero CO2 emission. The work focused on the development of a medium-scale solar reactor (10kW) based on the indirect heating concept. The solar reactor is composed of a cubic cavity receiver (20cm-side), which absorbs concentrated solar irradiation through a quartz window by a 9cm-diameter aperture. The reacting gas flows inside four graphite tubular reaction zones that are settled vertically inside the cavity. Experimental results in the temperature range 1740-2070K are presented: acetylene (C2H2) was the most important by-product with a mole fraction of up to about 7%, depending on the gas residence time. C2H2 content i...

2011-01-01

408

Characterisation of a re-cast composite Nafion 1100 series of proton exchange membranes incorporating inert inorganic oxide particles  

International Nuclear Information System (INIS)

A series of cation exchange membranes was produced by impregnating and coating both sides of a quartz web with a Nafion solution (1100 EW, 10%wt in water). Inert filler particles (SiO_2, ZrO_2 or TiO_2; 5-20%wt) were incorporated into the aqueous Nafion solution to produce robust, composite membranes. Ion-exchange capacity/equivalent weight, water take-up, thickness change on hydration and ionic and electrical conductivity were measured in 1 mol dm"-"3 sulfuric acid at 298 K. The TiO_2 filler significantly impacted on these properties, producing higher water take-up and increased conductivity. Such membranes may be beneficial for proton exchange membrane (PEM) fuel cell operation at low humidification. The PEM fuel cell performance of the composite membranes containing SiO_2 fillers was examined in a Ballard Mark 5E unit cell. While the use of composite membranes offers a cost reduction, the unit cell performance was reduced, in practice, due to drying of the ...

2010-09-01

409

Atmospheric emissions as a tool in evaluation of sustainability research in oil industry; Emissao atmosferica como uma ferramenta na avaliacao do desenvolvimento sustentavel na industria do petroleo  

Energy Technology Data Exchange (ETDEWEB)

This work is directly to analysis of atmosphere surrounding Ipiranga Refinery; witch is located in the city of Rio Grande, in estate of Rio Grande do Sul. The refinery is surrounded by neighborhood, witch are impacted by atmospheric emissions of refinery. The objective of this work is correlating the refinery to the inhabitants that lives near the refinery, using an environmental sustainability index. This work will be achieve by analysis of Polycyclic Aromatic Hydrocarbons (PAH) bounded in particulate matter with diameter of 100 {mu}m (PTS), the acquisition of health data on the city hospitals and correlation of this data with PAH concentrations in Particulate Matter. The Samples were obtain by FEPAM, witch have three samples sites in the center of city. The samples was obtained by a High Volume Sampler equipped with quartz fiber filters. The meteorological data important to this work, like wind direction and speed, will be obtain in Meteorological Station on ...

2008-07-01

410

An alpha-K{sub 3}PMo{sub 3}W{sub 9}O{sub 40} film loaded with silver nanoparticles: Fabrication, characterization and properties  

Energy Technology Data Exchange (ETDEWEB)

A composite film consisting of the mixed-addenda Keggin-type polyoxometalate alpha-K{sub 3}PMo{sub 3}W{sub 9}O{sub 40} (PMo{sub 3}W{sub 9}) and silver nanoparticles (AgNPs) was fabricated on quartz, silicon, and ITO by the layer-by-layer self-assembly method. The regular growth of the multilayer film was monitored by UV-vis spectroscopy, and the morphology was measured by atomic force microscopy (AFM). The multilayer film embedded by AgNPs exhibited the photo-luminescence ascribed to electronic transitions from excited states to d levels of the silver nanoparticles. The composite film also showed electrocatalytic activity towards reduction of NO{sub 2}{sup -}, H{sub 2}O{sub 2}, ClO{sub 3}{sup -}, BrO{sub 3}{sup -}, and IO{sub 3}{sup -} attributed to tungsten-centered and molybdenum-centered redox processes of PMo{sub 3}W{sub 9}.

2009-12-01

411

Abrasion wear studies with abrasives from brown coal beneficiation  

Energy Technology Data Exchange (ETDEWEB)

This paper evaluates abrasive jet wear tests, carried out on the ZUK-3M abrasion apparatus according to the GOSF 23.201-78 industrial standard. As abrasive material, brown coal coke dust, brown coal dust, power plant fly ash and quartz sand (for the purpose of comparison) were employed. Seventeen types of materials were blasted with abrasive jets, including a selection of steels, glass, rubber, SYS-pur plastics, cast basalt, Kawenit and vitroceramics. The test apparatus produced abrasive jet velocities between 12 and 130 ms/SUP/-/SUP/1 at rotor revolutions of 1,000 to 10,000 min/SUP/-/SUP/1. Blasted material samples were arranged at angles between 15 and 90 degrees. Various tables and graphs present abrasivity results. These results were employed for technical modifications of dedusting equipment in briquetting and coking plants, which led to a threefold increase in service life of abrasion endangered equipment parts. (8 refs.) (In German)

1983-01-01

412

A new approach towards anomalous fading correction for feldspar IRSL dating - tests on samples in field saturation  

Energy Technology Data Exchange (ETDEWEB)

Anomalous fading of the feldspar infrared stimulated luminescence (IRSL) signal hampers possibilities of using feldspar IRSL to obtain burial ages for sediments beyond the dating range of quartz optically stimulated luminescence. Here, we propose a new approach to quantify anomalous fading of the feldspar IRSL signal over geological burial times based on laboratory fading experiments. The approach builds on the description of the quantum mechanical tunnelling process recently proposed by Huntley [2006. An explanation of the power-law decay of luminescence. J. Phys. Condensed Matter 18, 1359-1365]. We show that our methods allow the construction of un-faded and natural IRSL dose-response curves as well as anomalous fading rates in field saturation. The predicted level of field saturation closely approximates the measured saturation level for five samples from fluvial deposits (Lower Rhine) known to be older than 1 Ma. The modelled anomalous fading rate in field ...

2008-02-15

413

NAME=\\  

Wastenet

...Surface Aerators Products and Equipment Find and compare a variety of surface aerators products and equipment on the world's largest environmental industry portal. ...

414

Absorption-Electrochemical Surface Decontamination  

International Science & Technology Center (ISTC)

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

415

Research on regimes transition of the boiling water two-phase flow in horizontal rectangular narrow heated channels  

Energy Technology Data Exchange (ETDEWEB)

Full text of publication follows: The heat transfer and flow in narrow channels has lots of advantages such as compact structure, high efficiency, design flexibility and so on. So it is widely used in the fields such as the new reactor core plate elements, the once-through stream generator, compact heat exchangers as well as electronic components. In recent years, more strong attentions have been attracted to the thermal-hydraulic characteristics and mechanism of the two-phase flow in narrow channels. As the flow regime characteristics of two-phase flow is fundamental one of them, the research on the two-phase flow regimes and the regime transitions in horizontal rectangular narrow heated channels can provide theoretical foundation and engineering directions to the whole research on the thermal-hydraulic characteristics and mechanism of the two-phase flow in narrow channels. The characteristics of two-phase flow regimes and regime transitions of boiling water in horizontal rectangular ...

2005-07-01

416

Research on regimes transition of the boiling water two-phase flow in horizontal rectangular narrow heated channels  

International Nuclear Information System (INIS)

Full text of publication follows: The heat transfer and flow in narrow channels has lots of advantages such as compact structure, high efficiency, design flexibility and so on. So it is widely used in the fields such as the new reactor core plate elements, the once-through stream generator, compact heat exchangers as well as electronic components. In recent years, more strong attentions have been attracted to the thermal-hydraulic characteristics and mechanism of the two-phase flow in narrow channels. As the flow regime characteristics of two-phase flow is fundamental one of them, the research on the two-phase flow regimes and the regime transitions in horizontal rectangular narrow heated channels can provide theoretical foundation and engineering directions to the whole research on the thermal-hydraulic characteristics and mechanism of the two-phase flow in narrow channels. The characteristics of two-phase flow regimes and regime transitions of boiling water in horizontal rectangular ...

2005-10-02

417

Occupational exposure to natural radionuclides due to mining activities in Ibadan, Southwestern Nigeria; Exposition professionnelle aux radionucleides naturels emis par les activites minieres a Ibadan au sud-ouest du Nigeria  

Energy Technology Data Exchange (ETDEWEB)

The activity concentrations of potassium, uranium and thorium in minerals and soil samples from a mining site in Ibadan, Southwestern Nigeria were measured using gamma ray spectroscopy method. Effective dose per annum has been calculated from the activity concentrations of dominant gamma-emitting natural radionuclides, potassium, uranium and thorium. Samples collected include minerals (beryl, quartz and feldspar), soil samples from the mining pits, heaps and undisturbed land around the mining site. The activity concentrations of {sup 40}K, {sup 238}U and {sup 232}Th, respectively in Bq kg-1 in the mineral samples were as follows: 1985 +- 16, 4.8 +- 0.9 and 11.8 +- 5.8 for beryl sample, 115.1 +- 27.9, 5.0 +- 1.3 and 6.3 +- 5.0 for feldspar samples and 1421 +- 122, <4.8 and 20.1 +- 3.5 for quartz samples. For the soil samples, the mean activity concentrations of {sup 40}K, {sup 238}U and {sup 232}Th, respectively, were 314.2 +- 5.7, 27.7 ...

2010-01-15

418

Solid radioactive waste management in Daya Bay Nuclear Power Station  

International Nuclear Information System (INIS)

This paper introduces the solid radwaste management system, treatment methods and its continuous improvement during the past 9 years in Guangdong Daya Bay Nuclear Power Station (GNPS). GNPS has paid great attention and made a lot of efforts to implement the principle of waste minimization with source control, improvement of treatment process and strict management, so the output of solid radwastes has annually decreased since 1994. In 2002, the output of solid radwastes in GNPS was 63.5 m"3, only 50% of 1995 (127 m"3), reached the advanced level as the same type NPPs in France. During the period 1994-2002, the accumulated production of solid radwaste Packages in GNPS is 1563.51 m"3 only 18% of the design value; all the packages meet the standard and requirement for safe disposal. Besides, this paper analyzes some new technical processes and presents some proposals for further decreasing the ...

2004-05-01

419

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

Energy Technology Data Exchange (ETDEWEB)

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

1987-12-31

420

Promising electrolyte materials for the coming lithium secondary batteries. Lithium ion conductive inorganic solid electrolytes; Jisedai lithium niji denchiyo denkaishitsu. Muki kotai denkaishitsu  

Energy Technology Data Exchange (ETDEWEB)

This paper describes inorganic solid electrolytes from a viewpoint of electrolytes for lithium batteries. Lithium ion conductive inorganic solid electrolytes are largely divided into crystalline and amorphous substances. Crystalline substances are known as LiI and Li3N, and also oxygen acid salt. However, when considering application to a battery, its large grain boundary resistance and electrochemical instability would be a problem. Lithium ion conductive amorphous solid electrolytes are divided into an oxide system and a sulfide system. Since most of them do not contain transition metal elements, they are stable against electrochemical reduction, and ions move isotropically in electrolyte. Therefore, ion conduction paths across the grain boundaries may be connected more easily, forming an electrolyte with low grain boundary resistance. As a result of the efforts of the authors in searching new additives substituting LiI, ...

1997-11-05

421

Operation of a laboratory-scale tubular digester on pigery waste  

Energy Technology Data Exchange (ETDEWEB)

Three inclined tubular digesters of 13- to 15-litre volume were operated at temperatures between 20 and 30 degrees C with hydraulic retention times of 10-15 days on pig slurry of 10%, 5% and 2.5% Total Solids content. Tube inclination of 16-20 degrees gave no scumming problems. Solids were retained, giving improved gas yields when compared with literature values for conventional stirred digesters. Solids retention is affected by the size of the digester exit and appears to be greater with slurry of low solids content. There is a link between the movement of solids and gas along, and out of, the digester which can lead to unstable oscillating gas production. Tracer studies showed soluble components of the slurry mixed throughout the whole volume of the digester in 25% of the hydraulic retention time or less. Solids moved in well dispersed plug flow. Gas ...

1986-01-01

422

Methodology to evaluate the energy associated to the industrial solid wastes: application in a metropolitan region of Campinas, Sao Paulo state, Brazil; Metodologia para avaliacao da energia associada ao residuo solido industrial: aplicacao a regiao metropolitada de Campinas  

Energy Technology Data Exchange (ETDEWEB)

The aim of this work is to the application of a methodology to evaluate the energy associated to the industrial solid wastes in the metropolitan region of Campinas. The methodological route proposed is: the characterization of the research area and the production/management of the industrial solid wastes; the energetic classification and the qualitative/quantitative research of the energy associated to the industrial solid wastes; and, the valuation of the applicability of the energetic utilization mechanisms proposed to the region. This methodology when applied at the Campinas metropolitan region proved to be valid and it resulted in a synthetically presentation of the social and environmental reality of the industrial sector and the destination of the wastes, as well as it indicated the potentialities related to the energetic utilization of the industrial solid waste in the region. With the obtained ...

2004-07-01

423

Maintenance Implementation Plan for solid waste  

Energy Technology Data Exchange (ETDEWEB)

This Maintenance Implementation Plan (MIP) has been developed for. implementation of the US Department of Energy (DOE) Order 4330.4A. Maintenance Implementation Program (DOE 1990) at the Hanford Site Solid Waste complex. It addresses maintenance functions associated with Solid Waste Management, which includes the field operational group and the facilities operational group. An assessment of the existing maintenance programs for Solid Waste was performed, and the results of this assessment were evaluated to determine corrective actions required to bring Solid Waste Maintenance into compliance with the order. The MIP assessment disclosed that most elements defined in the order are currently implemented for Solid Waste. It also identified issues which must be addressed to bring the maintenance function into full compliance with DOE Order 4330.4A. These include documentation of the ...

1992-06-01

424

Experimental Study of Plasma-Surface Interaction and Material Damage Relevant to ITER Type I Elms  

International Nuclear Information System (INIS)

The paper presents experimental investigations of main features of plasma surface interaction and energy transfer to the material surface in dependence on plasma heat loads. The experiments were performed with QSPA repetitive plasma pulses of the duration of 0.25 ms and the energy density up to 2.5 MJ/m2. Surface morphology of the targets exposed to QSPA plasma screams is analyzed. Relative contribution of the Lorentz force and plasma pressure gradient to the resulting surface profile is discussed. development of cracking on the tungsten surface and swelling of the surface are found to be in strong dependence on initial temperature of the target.

2006-01-01

425

Wet limestone FGD solids analysis by thermogravimetry  

Energy Technology Data Exchange (ETDEWEB)

Wet limestone scrubbing is once again becoming a popular technology for removal of sulfur dioxide (SO{sub 2}) from power plant emissions. Critical to the operation of wet limestone flue gas desulfurization (FGD) systems is accurate chemical analysis of scrubber solids. The analytical technique of thermogravimetry is ideal for this application, as the instrument can give precise readings of the principal scrubber solids components, calcium sulfite/sulfate hemihydrate, calcium sulfate dihydrate (gypsum), and unused calcium carbonate. The data provides plant chemists, engineers, and operators with information needed to fine-tune scrubber operation and detect process upsets. (orig.)

2004-07-01

426

Waste management units - Savannah River Site. Volume 1, Waste management unit worksheets  

Energy Technology Data Exchange (ETDEWEB)

This report is a compilation of worksheets from the waste management units of Savannah River Plant. Information is presented on the following: Solid Waste Management Units having received hazardous waste or hazardous constituents with a known release to the environment; Solid Waste Management Units having received hazardous waste or hazardous constituents with no known release to the environment; Solid Waste Management Units having received no hazardous waste or hazardous constituents; Waste Management Units having received source; and special nuclear, or byproduct material only.

1989-10-01

427

Solid State Photovoltaic Research Branch  

Energy Technology Data Exchange (ETDEWEB)

This report summarizes the progress of the Solid State Photovoltaic Research Branch of the Solar Energy Research Institute (SERI) from October 1, 1988, through September 30,l 1989. Six technical sections of the report cover these main areas of SERIs in-house research: Semiconductor Crystal Growth, Amorphous Silicon Research, Polycrystalline Thin Films, III-V High-Efficiency Photovoltaic Cells, Solid-State Theory, and Laser Raman and Luminescence Spectroscopy. Sections have been indexed separately for inclusion on the data base.

1990-09-01

428

Review on the status of solid radwaste management in Korean NPPs  

International Nuclear Information System (INIS)

To minimize the low and intermediate-level solid radwaste volume, the reduction efforts were persisted in Korean NPPs. As a result, annual average waste volumes were reduced to 194 drums per unit at last year. In this paper we confirmed 250 drums/unit-yr, EPRI URD management goal, and management condition for solid radwaste volume. Also, through the sample assessment of specific Korean NPP opened to the public, we could make sure that the prediction of saturation year for interim storage facility is fully suitable.

2003-10-01

429

Realization of entirely solid lithium ion batteries; Realisation d`accumulateurs a ions lithium entierement solides  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a prototype of an entirely inorganic lithium ions battery cell. LiCoO{sub 2} thin film cathodes and Li{sub 4/3}Ti{sub 5/3}O{sub 4} thin film anodes have been deposited on Li{sub 3x}La{sub 2/3-x}TiO{sub 3} sintered solid electrolyte pellets and the performances of these battery cells have been tested. (J.S.) 5 refs.

1996-12-31

430

Multiple stress aging of solid-dielectric extruded dry-cured insulation systems for power transmission cables  

Energy Technology Data Exchange (ETDEWEB)

A detailed examination of the aging processes that may take place in solid-dielectric extruded-type high voltage transmission cables under dry conditions is presented. Particular emphasis is placed on the aging process as affected by the separate and simultaneous action of four main aging factors, namely the electrical, mechanical and thermal stresses, and the physical and chemical environment. A number of pertinent aging models are considered and their validity and applicability to accelerated aging tests on solid-type transmission cables are discussed.

1994-01-01

431

Heat storage composition  

Energy Technology Data Exchange (ETDEWEB)

A heat storage compostion comprises sodium sulfate decahydrate as main component, a supercooling inhibitor, and a solid-liquid separation inhibitor. The composition is characterized in that hydraulic calcium sulfate and/or calcium sulfate dihydrate is contained as the solid-liquid separation inhibitor in an amount of 2-15 wt% base on the whole weight of the composition, whereby the solid-liquid separation, i.e. the sedimentation of the anhydrous sodium sulfate during the phase transition, is effectively prevented and the long-term stability is improved. The long-term stabilty of the composition can be more improved by addition of a silcia series of thickener.

1987-05-05

432

Feasibility study on the management of the disposal of Bangkok municipal waste. Final report  

Energy Technology Data Exchange (ETDEWEB)

In January, 1985, the Government of Thailand sought assistance from the United States Trade and Development Program (USTDP) to undertake a feasibility study to review and update the solid waste management master plan, with particular emphasis to be placed on waste disposal methods. In April, 1985, the USTDP engaged the firm of Engineering and Economic Research, Inc. to carry out a definitional/prefeasibility study to assess the potential of a project for solid waste management and energy production using municipal solid waste as fuel.

1989-09-01

433

Child mortality from solid-fuel use in India: a nationally-representative case-control study - article no. 491  

Energy Technology Data Exchange (ETDEWEB)

Most households in low and middle income countries, including in India, use solid fuels (coal/coke/lignite, firewood, dung, and crop residue) for cooking and heating. Such fuels increase child mortality, chiefly from acute respiratory infection. There are, however, few direct estimates of the impact of solid fuel on child mortality in India. Methods: We compared household solid fuel use in 1998 between 6790 child deaths, from all causes, in the previous year and 609 601 living children living in 1.1 million nationally-representative homes in India. Analyses were stratified by child's gender, age (neonatal, post-neonatal, 1-4 years) and colder versus warmer states. We also examined the association of solid fuel to non-fatal pneumonias. Solid fuel use was very common (87% in households with child deaths and 77% in households with living children). After adjustment for ...

2010-08-17

434

Acetylacetone in hydrogen solids: IR signatures of the enol and keto tautomers and UV induced tautomerization  

British Library Electronic Table of Contents (United Kingdom)

Acetylacetone is isolated in hydrogen matrices and is investigated by means of infrared spectroscopy, combined with theoretical calculations. The two stable enol and keto tautomers are well characterized. The keto/enol ratio in solid parahydrogen is found to be higher than in classical matrices. While vibrational bands of the enol form are broad, with bandwidths depending on the vibrational mode, those of the keto form are narrow. A KrF laser excitation is used to induce the enol/keto tautomerization in solid parahydrogen. The kinetics of the interconversion is followed, highlighting a non-direct tautomerization process.

2011-01-01

437

The alkali sorption process by solid sorbents at high temperature  

Energy Technology Data Exchange (ETDEWEB)

The removal of toxic metals and alkalis from gas streams at high temperatures was investigated. This is important for the development of coal-fired combined cycle power generation systems.

2000-03-01

438

Solubility of AmOHCO{sub 3} in aqueous solution under atmospheric conditions  

Energy Technology Data Exchange (ETDEWEB)

Modeling calculations on the solubility of americium have indicated that basic americium carbonate, and not americium trihydroxide, is the solubility-controlling solid in the pH range from 6 to 10 under the influence of atmospheric CO{sub 2}. The solubility of crystalline {sup 243}AmOHCO{sup 3} has been investigated in batch experiments in near-neutral and basic solutions as a function of dissolution time in 0.1 M NaClO{sup 4} at room temperature under oxic conditions. After the solutions reached steady-state conditions, the influence of dissolved solids on the americium concentration in the supernatant solution was studied by utilizing several experimental methods to separate the solution phase from the solid. The solids were characterized by X-ray powder diffraction analysis.

1987-12-01

439

Solid-state fermentation of lignocellulotic materials for the production of enzymes by the white-rot fungus Trametes hirsuta in a modular bioreactor  

British Library Electronic Table of Contents (United Kingdom)

Abstract Trametes hirsuta, a filamentous basidiomycete, was successfully cultivated in solid-state fermentation (SSF) on a mixture of pine wood chips and orange peel in a novel bioreactor that allows mixing of the inoculated solid material during the fermentation. Copper sulfate or xylidine (2,5-dimethylaniline) were added to enhance the production of enzymes, especially laccases. For comparison, Trametes hirsuta was also cultivated in submerged conditions. The effect of additives in SSF was low, whereas the choice of the solid material and the rotation of the reactor vessel showed a significant influence on the enzyme production. The space-time yields for the fermentations were calculated and showed that SSF on low-cost substrates can effectively produce extracellular enzymes at a suffici...

2011-01-01

440

SOLID STATE RESEARCH OF THE APPLIED PHYSICS ...  

Science.gov (United States)

... 10 TIN TELLURIDE Preparation of Tin Telluride Single Crystals ..... 12 ... TIN TELLURIDE Preparation of Tin Telluride Single Crystals ...

1962-07-16

441

Radiation deamination of tetracycline. [Gamma radiation  

Energy Technology Data Exchange (ETDEWEB)

The fundamental product of tetracycline hydrochlorine gamma radiolysis was separated in its solid state. From the results of spectroscopic studies it has been established that it is des-N,N-dimethylaminotetracycline.

1980-01-01

442

Physics of laser fusion. Volume IV. The future development of high-power solid-state laser systems  

Energy Technology Data Exchange (ETDEWEB)

Solid state lasers, particularly neodymium glass systems, have undergone intensive development during the last decade. In this paper, we review solid state laser technology in the context of high-peak-power systems for inertial confinement fusion. Specifically addressed are five major factors: efficiency, wavelength flexibility, average power, system complexity, and cost; these factors today limit broader application of the technology. We conclude that each of these factors can be greatly improved within current fundamental physical limits. We further conclude that the systematic development of new solid state laser madia, both vitreous and crystalline, should ultimately permit the development of wavelength-flexible, very high average power systems with overall efficiencies in the range of 10 to 20%.

1982-11-01

443

Physicochemical investigation of the behavior of elements in chloride melts in the presence of solid phases based on phosphates of polyvalent elements. II. Behavior of strontium and barium  

Energy Technology Data Exchange (ETDEWEB)

The distribution of the alkaline earth elements strontium and barium between the solid phases of phosphates of transition elements of group 4 and chloride melts was studied. The distribution coefficients of strontium and barium were found at T = 700-800/sup 0/C. Phosphates of the type NaM/sub 2//sup (IV)/(PO/sub 4/)/sub 3/, where M/sub (IV)/ represents titanium, zirconium, and hafnium, were used as the solid phases. It was established that there is an enrichment of the precipitates with the distributed components. The distribution coefficient depends on the nature of the solid phase and the temperature. It was suggested that M/sup (II)/ x M/sub 4//sup (IV)/(PO/sub 4/)/sub 6/ is formed in processes of distribution, where M/sup (II)/ represents Sr, Ba.

1987-07-01

444

Non-Markovian dephasing in solid-state single photon sources  

CERN Document Server

Solid-state single-photon sources have many desirable features that make them attractive for applications in quantum information processing. However, the phase coherence of such devices can be severely compromised by coupling to the solid-state environment. Here, we study the effects of realistic dephasing environments on a pair of solid-state single photon sources in the context of quantum interference effects such as the Hong-Ou-Mandel dip. By means of exact solutions for the non-Markovian dynamics of the sources, we show that the resulting loss of visibility depends crucially on the timing of photon detection events. Our results demonstrate that the effective visibility can be improved via temporal post-selection, and also that time-resolved interference can be a useful probe of the interaction between the emitter and its host environment.

2008-01-01

445

NASA - Waste Not  

Science.gov (United States)

Jun 4, 2004 ... On a two-year trip to Mars, according to one estimate, a crew of six humans will generate more than six tons of solid organic waste--much of ...

446

Mucinous cystadenoma of the pancreas with predominant stroma creating a solid tumor  

UK PubMed Central (United Kingdom)

BackgroundMucinous cystic neoplasm (MCN) of the pancreas is basically cystic epithelial neoplasm, unilocular or multilocular, occurring almost exclusively in women.Case...Full Text Available

447

Molten Boron Phase-Change Thermal Energy Storage ...  

Science.gov (United States)

... Advanced thermal storage systems based on very high temperature solid materials such as boron carbide or graphite have been investigated for ...

2011-06-01

448
449

Measured Temperatures of Solid Rocket Motors Dump Stored ...  

Science.gov (United States)

... TARGET SENSOR-MK 80 SERIES BOMBS ... 5-inch-, and 2.75-inch- diameter rocket motors that ... balance when compared to incoming solar radiation ...

1989-07-01

450

Kinetic behavior of solid particle in chemical-looping combustion: suppressing carbon deposition in reduction  

Energy Technology Data Exchange (ETDEWEB)

In order to apply chemical-looping combustion to a practical power plant, carbon deposition on the solid particle is one of the key problems to be overcome. Six kinds of solid particles were examined to clarify the kinetic behavior of carbon deposition. The effects of the solid composition, feed gas composition, and reaction temperature on carbon deposition were investigated by thermogravimetrical reactor on the basis of NiO/YSZ particle. From the viewpoints of both reactivity and resistance against carbon deposition, the particle of NiO mixed with YSZ (i.e., yttria-stabilized zirconia) was found to be a good candidate for chemical-looping combustion. It has been observed that carbon deposition could be completely avoided with very low concentration of water vapor. By means of a proposed model, the condition that carbon deposition would be avoided was identified. 12 refs., 8 figs., 2 tabs.

1998-03-01

451

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

Science.gov (United States)

major radius of the toroidal containment volume. The containment time was calculated using equation (4) as derived in references 16 and 17. The solid ...

454

ELECTRIC AND GALVANOMAGNETIC PROPERTIES OF ...  

Science.gov (United States)

... Abstract : The electric resistance in weak (diluted) solid solutions of the Pd-Ag and Fe-W systems, as wellAS THE Hall effect in a Pd-Ag system ...

1961-06-27

456

Crystal Chemistry of Ceramic/Mineral Systems  

Science.gov (United States)

... 1. Reeber, RR, Kusy, RP, Yu, N. and Chu, WK " Formation of a Solid Lubricant in Boron Carbide by Nitrogen Ion Implantation and Laser Annealing ...

1992-12-08

457

Compaction of dust clumps in a protostellar cloud  

Energy Technology Data Exchange (ETDEWEB)

Necessary conditions are derived for compact aggregates of solid matter to develop from loose local clumps of dust grains in a contracting protostellar cloud.

1984-01-01

458

Bacterial body plans  

UK PubMed Central (United Kingdom)

The bacterium Serratia marcescens produces a plethora of multicellular shapes of different colorations on solid substrates, allowing immediate visual detection of varieties. Such a...Full Text Available

2008-07-01

459

Aerodynamic Static Differential Pressure  

Science.gov (United States)

aerodynamic force and moment values. Only the solid and the 25 percent porous dishes were tested for the static pressure values used primarily to determine ...

461

A novel accelerated oxidative stability screening method for pharmaceutical solids  

British Library Electronic Table of Contents (United Kingdom)

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

2011-01-01

462

A Theoretical Solid Oxide Fuel Cell Model for Systems Controls and Stability Design  

Science.gov (United States)

As the aviation industry moves toward higher efficiency electrical power generation, all electric

2008-01-01

463

Progress report, December 1, 1979-November 30, 1980. [Chemical poisoning of heterogeneously catalyzed reactions on transition metal surfaces  

Energy Technology Data Exchange (ETDEWEB)

The mechanism of chemical poisoning of model heterogeneously catalyzed reactions on transition metal surfaces is studied. Clean Mo(001) surfaces were characterized; results suggest a first-layer contraction of 10% of the bulk interlayer spacing. Characterization of clean Co(0001) surfaces is underway. Decomposition of formic acid on Mo(001) surfaces is being studied. (DLC)

1980-01-01

464

Oxidation and adsorption of Co(II)EDTA 2- complexes in subsurface materials with iron and manganese oxide grain coatings  

Science.gov (United States)

Batch interaction experiments were performed under aerobic conditions to characterize the adsorption behavior and valence speciation of CoEDTA complexes (equimolar at 10 -5 mol/L) in a series of Pliocene subsurface sediments containing various amounts of Fe and Mn oxides. The experiments were performed in 0.003 mol/L Ca(ClO 4 ) 2 with a solids concentration of 500 g/L at variable pH (4-9) and at the natural pH of the sediments (pH = 8.3). Three of these subaerial sediments (Ringold 1, 2, 3) contained significant quantities of extractable Fe and Mn, while the fourth (Ringold 4) was virtually devoid of sesquioxide precipitates. Microscopic and mineralogic analyses of the most heavily encrusted material (Ringold 2) showed that the oxides existed as intergrain cements and contained crystalline goethite and rancieite/todorokite. Adsorption on a synthetic analog sorbent (0.6 mass % ferrihydrite-coated sand) over a range in pH showed that, while both Co(II)EDTA 2- and ...

1995-11-01

465

Investigating of composition, structure and properties of Si modification under variable dose ions implantation influence  

International Nuclear Information System (INIS)

Interest to thin film of metals' silicides first of all is conditioned intrinsic al them unique physical properties. On their basis of it is possible to produce extremely sophisticated devices of solid-state electronics, production which needs the controlled change of physics, chemical and electrical properties with high-level of accuracy. On the present time most are in detail investigated composition, structure and properties of three-dimensional samples of metals' silicides. In the last years the intensive are led to researches in the direction of creation and study of physical-chemical properties thin (500-1000 Angstroms) and ultrafine (100-120 Angstroms) films silicides. It has information about composition, morphology of surface and emission of properties of thin film of silicides of barium, of cobalt and of palladium, was obtained in conditions of ultra-high vacuum. Low energy ion implantation and further annealing on composition, ...

466

Buried Paleo-Phreatic Playa is the Primary Source of Salinity in the Rio Grande and Rio Grande Aquifer, El Paso-Juarez Valley  

Science.gov (United States)

The Rio Grande alluvial floodplain aquifer between El Paso/Juarez and Fort Quitman, Texas has been intensively tilled and irrigated since 1910. Almost since that time, the Rio Grande and its interconnected alluvial aquifer in this stream reach have been affected by excessive salinity problems. Presently, salinity of surface water and groundwater increases from 800 to 2000 mg/L total dissolved solids (TDS) near El Paso, Texas to 2500 to 5500 mg/L TDS near Fort Quitman, Texas, approximately 115 km downstream. Chloride (Cl) and Chloride/Bromide (Cl/Br) ratios increase downstream, with a marked increase in salinity beginning about 45 km below El Paso. Groundwater sampling in an intensively investigated reach of the floodplain aquifer, extending from 35 to 60 km below El Paso identified two distinct water types. The first water type (17 samples) is a relatively dilute groundwater containing 1000 to 2000 mg/L TDS, 250 to 600 mg/L Cl, and Cl/Br ...

2005-12-01

467

Uranium oxides. Specific surface measurement by nitrogen adsorption  

International Nuclear Information System (INIS)

Determination of the specific surface of uranium oxides: UO_2 and U_3O_8 using a simplified equation derived from the Brunauer, Emmett and Teller theory. The method is suitable for samples having a surface between 6 to 50 m"2.

468

Heat Transfer Augmentation in a Compact Heat Exchange Pedestal Array.  

Science.gov (United States)

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

2004-01-01

469

First Evidence of Division and Accumulation of Viable but Nonculturable Pseudomonas fluorescens Cells on Surfaces Subjected to Conditions Encountered at Meat Processing Premises?  

UK PubMed Central (United Kingdom)

Cleaning and disinfection of open surfaces in food industry premises leave some microorganisms behind; these microorganisms build up a resident flora on the surfaces. Our goal was to explore the phenomena...Full Text Available

2007-05-01

470

Binary Pseudo-Random Gratings and Arrays for Calibration of Modulation Transfer Function of Surface Profilometers  

Energy Technology Data Exchange (ETDEWEB)

In the present work, we describe application of binary pseudo-random gratings (BPRG) and arrays (BPRA) as effective 1D and 2D test surfaces suitable for calibration of different surface profilometers, including a number of interferometric microscopes and scatterometers.

2009-06-17

471

A custom-made guide-wire positioning device for Hip Surface Replacement Arthroplasty: description and first results  

UK PubMed Central (United Kingdom)

BackgroundHip surface replacement arthroplasty (SRA) can be an alternative for total hip arthroplasty. The short and long-term outcome of hip surface replacement arthroplasty mainly...Full Text Available

472

Treatment for dismantled radioactive solid waste from the TRIGA Mark-2 and 3  

Energy Technology Data Exchange (ETDEWEB)

Radioactive wastes are generally classified into 3 type depending on their physical property: liquid, solid and gaseous type. State-of -the art concerning liquid waste treatment has already been published; KAERI/TR-1315/99. Solid wastes classification package and treatment method will be studied to effectively manage them during the practical decommissioning work. All of the spent fuel produced during the operation of the TRIGA Mark-2 and 3 have been transported to the US last year, 1998, according to the spent fuel management strategy set-up by the US government for the non-proliferation of nuclear energy. Solid wastes are mainly all equipment existing inside of the reactors, activated concrete among the bio-shielded concrete, pipes, pimps, resin filter and it's housings, heat-exchangers, liquid waste storage tanks, to radioactive waste storage treatment facilities and so on. Solid wastes are ...

1999-06-01

473

Target R and D at JAERI  

Energy Technology Data Exchange (ETDEWEB)

We proposed a solid and a mercury target concepts through the preliminary conceptual design. To feasible these concepts, analysis and experimental works are being carried out. This paper introduces an outline of present status of target R and D such as heat transfer augmentation experiments for the solid target, mercury flow tests with a loop of maximum flow rate of 15L/min, flow pattern measurements for a cold source moderator etc. as well as preliminary conceptual design works. (author)

1999-03-01

474

Solid state NMR, basic theory and recent progress for quadrupole nuclei with half-integer spin  

International Nuclear Information System (INIS)

This review describes the basic theory and some recently developed techniques for the study of quadrupole nuclei with half integer spins in powder materials. The latter is connected to the introduction of the double rotation (DOR) by A. Samoson et al. (1) and to the introduction of the multiple quantum magic-angle spinning (MQ MAS) technique by L. Frydman et. al. (2). For integer spins, especially the solid-state deuterium magnetic resonance, we refer to the review of G.L. Hoatson and R.L. Vold: ''"2H-NMR Spectroscopy of Solids and Liquid Crystals'' (3). For single crystals we refer to O. Kanert and M. Mehring: ''Static quadrupole effects in disordered cubic solids''(4) and we would like also to mention the ''classic'' review of M.H. Cohen and F. Reif: ''Quadrupole effects in NMR studies of solids'' (5). Some more recent reviews in the field under study are D. Freude and J. Haase ''Quadrupole effects in ...

1998-12-01

475

Sealant Research for solid oxide fuel cells  

International Nuclear Information System (INIS)

The objective of this work is to develop sealing materials for solid oxide fuel cells (SOFCs). A suitable sealant must form strong, dense bonds with SOFC components, be chemically and mechanically compatible with the components, be stable at 1000 degrees C in the operating environment of the SOFC (H_2 and H_2O on the anode side, O_2 on the cathode side), and must be nonconductive.

1992-07-01

476

Satellite power systems (SPS) concept definition study (Exhibit D). Solid-state amplifier investigation. Final report  

Energy Technology Data Exchange (ETDEWEB)

Data resulting from a continuing effort to provide system/subsystem definition data to aid in the evaluation of the SPS program concept is presented. The specific data described relate to the proposed use of solid state devices as microwave power amplifiers in the satellite microwave power transmission subsystem.

1981-04-01

477

Room temperature synthesis of tri-, tetrasubstituted imidazoles and bis-analogues by mercaptopropylsilica (MPS) in aqueous methanol: application to the synthesis of the drug trifenagrel  

British Library Electronic Table of Contents (United Kingdom)

The heterogeneous solid catalyst, mercaptopropylsilica (MPS), has been prepared by a modified procedure in water and its structure confirmed by solid state carbon-13 CP-MAS NMR spectrum. This catalyst has been efficiently utilized for the synthesis of a wide variety of tri-, tetrasubstituted imidazoles and their bis-analogues at room temperature. The protocol was further explored for the synthesis of the drug trifenagrel.

2010-01-01

478

Quantum theory of light interstitial diffusion and other aspects of inert gas motion in solids  

International Nuclear Information System (INIS)

Most diffusion phenomena in solids can be understood (or sometimes misunderstood) on a purely classical model. For light interstitials (hydrogen isotopes, the positive muon, and potentially He) there may be anomalous temperature dependences, and isotope effects, and anomalous response to electric fields and temperature gradients. Some of these anomalies are quantal in origin, and will be discussed. (author).

1980-03-01

479

Process for uranium processing  

International Nuclear Information System (INIS)

To the crushed ore leaching is applied. The resulting solid-liquid mixture is fed to a hydro-cyclon grading facility; here the superfine grain is separated before the concentrated mixture can be filtered or centrifuged. The grading is done in several steps. From the liquid, ultimately ridded of the solid, uranium compounds are precipitated and the yellow cake is obtained. (DG).

1984-11-12

480

Municipal solid waste management in Lebanon: the need for an integrated approach  

International Nuclear Information System (INIS)

Full text.This study focuses on the management of municipal solid waste (MSW) in Lebanon. It addresses the current status of MSW management in Lebanon in terms of collection, transport and disposal, infers the associated impacts of such practices and discusses mitigation measures and finally proposes basic guidelines for a national strategy for solid waste management in the country. The study is based on available previous investigations and on a field survey of 113 villages in four different countries. The study revealed the absence of an effective environmental policy and poor collection and disposal methods throughout the country, except for the Greater Beirut Area (G A), where better solid waste management practices are employed. Although collection of MSW outside GBA was found to be acceptable by local authorities, resources (labor and equipment) were not used efficiently. Furthermore, treatment of collected waste is ...

2000-11-23

481

Microwave Combustion and Sintering Without Isostatic Pressure  

Energy Technology Data Exchange (ETDEWEB)

This investigation involves a study of the influence of key processing parameters on the heating of materials using microwave energy. Selective and localized heating characteristics of microwaves will be utilized in the sintering of ceramics without hydrostatic pressure. In addition, combustion synthesis will be studied for the production of powders, carbides, and nitrides by combining two or more solids or a solid and a gas to form new materials. The insight gained from the interaction of microwaves with various materials will be utilized in the mobilization and subsequent redeposition of uranium.

1998-10-20

482

Measurement of the susceptibility of solid "3He along the melting curve from 20 mK down to the nuclear ordering temperature  

International Nuclear Information System (INIS)

The susceptibility of solid "3He is deduced from multiple echoes observed in pulsed NMR experiments. It follows a Curie Weiss law at high temperature, increases faster than this law below 5 mK and drops abruptly around 1 mK. (Auth.).

1977-02-01

483

Limiting-dilution analysis of T cells extracted from solid human lung tissue: comparison of precursor frequencies for proliferative responses and lymphokine production between lung and blood T cells from individual donors.  

UK PubMed Central (United Kingdom)

This study evaluates the frequency and functions of immunocompetent T cells at the clonal level in solid human lung tissue versus peripheral blood. Enzymatic digestion of slices of histologically normal...Full Text Available

1988-08-01

484

Lattice parameters and thermal expansion of solid ortho-deuterium  

Energy Technology Data Exchange (ETDEWEB)

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

1984-01-01

485

Kinetics of achieving equilibrity at the sorption of radionuclides  

International Nuclear Information System (INIS)

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

486

Investigation of radiation defects in solids using the EXAFS method  

International Nuclear Information System (INIS)

The exafs method is proposed as a more informative, universal one to investigate the radiation defects in solids. The successful results as obtained by the author using the synchrotron radiation source are reported for the first time. The measurements were carried out in GaAsP crystals irradiated with 50 MeV electrons.

1978-02-15

487

Interphase mass transfer in the separation of isotopes in countercurrent columns (liquid-solid systems)  

International Nuclear Information System (INIS)

The results of calculated and experimental investigation of interphase isotopic exchange efficiency in countercurrent columns are given when separation processes of isotope mixtures are taken place with use of liquid-solid systems. Effect of liquid phase flow on transfer unit height in ion exchange separation of boron, lithium, nitrogen isotopes is considered. 40 refs.; 5 figs.

488

Intermediates to ethylene glycol: carbonylation of formaldehyde catalyzed by Nafion solid perfluorosulfonic acid resin  

Energy Technology Data Exchange (ETDEWEB)

Details of a series of reactions for the production of ethylene glycol using a catalyst of Nafion solid perfluorosulfonic acid resin was detailed. The reactions included the carbonylation of formaldehyde and esterification and then hydrogenation of the product of the carbonylation, glycolic acid. Other preparations included in the work included methyl glycolate, acetylglycolic acid, methyl acetylglycolate, and methyl methoxyacetate.

1983-01-01

489

Influence of tumour volume and cell kinetics on the response of the solid Yoshida sarcoma to hyperthermia (42 degrees C).  

UK PubMed Central (United Kingdom)

The cytokinetic response of the solid Yoshida sarcoma to hyperthermia was examined at two tumour volumes, 1.0-1.5 ml and 3.0-3.5 ml. The tumour, growing on the feet of rats, was heated at 42 degrees...Full Text Available

1980-01-01

490

Formation of nano-sized particles of a solid electrolyte by laser ablation  

Energy Technology Data Exchange (ETDEWEB)

Nano-sized particles of a lithium ion conductive solid electrolyte, LiTi{sub 2}(PO{sub 4}){sub 3}, were prepared by laser ablation. The obtained particles were ca. 10nm in diameter. X-ray powder diffraction and Raman spectroscopy showed that they were amorphous with local structure similar to the crystalline counterpart. They were crystallized by the heating at ca. 630{sup o}C. (author)

2005-08-26

491

Explicit equation for particle settling velocities in solid-liquid systems  

Energy Technology Data Exchange (ETDEWEB)

Zanker has recently presented nomographs for determining particle settling velocities in solid-liquid systems. These nomographs were based on the general correlations developed by Barnea and Mizrahi and Barnea and Mednick. This work presents an equation directly computing particle settling velocities, eliminating the uncertainty associated with nomographs.

1981-11-01

492

Basic study of solid oxide fuel cells. Part 5: investigation of fuel cell materials  

Energy Technology Data Exchange (ETDEWEB)

Solid Oxide Fuel Cell (SOFC) is expected as a new power generation source. The development of SOFC is being conducted by CRIEPI, and so far several reports of the reults were presented. This report examines materials of SOFC. For the purpose, cells were made using some of typical materials and manufacturing processes, and cell performance tests were carried out.

1991-01-01

493

Visualization and measurement of pressurized multiphase flow using neutron radiography of JRR-3M system  

Energy Technology Data Exchange (ETDEWEB)

Concerning the transient phenomenon of solid-gas two-phase flow, an attempt was made to visualize and measure a flow phenomenon in which three-dimensional bubbles occurred, grew and collapsed in the vicinity of a gas injection nozzle while solid particles were circulating. Such a phenomenon could not or hardly be visualized and measured by conventional methods. Such two-phase flow was visualized using neutron radiography, its characteristics measured and the usefulness of the visualization by neutron radiography confirmed. For this purpose, three-dimensional fluidized bed vessels, rectangular or cylindrical-shaped, made of steel or aluminum sheet, were prepared. Polyethylene or glass beads were used as solid particles and activated carbon particles as the tracer. In the experiment, nitrogen gas was blown into the vessel from one nozzle and distributors provided at the bottom of the vessel and exhausted from the top via the ...

1998-01-01

494

Solid waste research and development: A perspective from Pacific Northwest Laboratory  

Energy Technology Data Exchange (ETDEWEB)

The need for research and development (R&D) of technologies and approaches for sound, effective solid waste management is unquestionable. While many advances have been made by the government and private sectors, still more are needed. Resources for conducting R&D, even at the federal level, are limited however, and thus it is critical that resources be distributed as wisely as possible. The US Department of Energy has a vested interest in developing technologies and approaches for managing solid waste because solid waste management is strongly linked to energy use and environmental impacts. This federal role is needed to address the national and international impacts that can result from the cumulative effects of decisions being made at local, county, state, and regional levels. At Pacific Northwest Laboratory (PNL), one of DOE`s R&D laboratories, we are developing an integrated solid waste ...

1992-11-01

495

Regional integrated solid waste management: an optimization model for northern Lebanon  

International Nuclear Information System (INIS)

Full text.Increased environmental concerns and the emphasis on material and energy recovery are gradually changing the orientation of municipal solid waste (MSW) management and planning. In this context, the application of optimization techniques have been introduced to design the least cost solid waste management systems, considering the variety of management processes (recycling, composting, anaerobic digestion, incineration and land filling) and the existence of uncertainties associated with the number of system components and their interrelations. This study presents a model that was developed and applied to serve as a solid socio-economic and environmental considerations. The model accounts for solid waste generation rates, composition, collection, treatment, disposal as well as potential environmental impacts of various MSW management techniques. The model follows a linear programming formulation ...

2000-11-23

496

Recycling of AZ31 Mg alloy with high purity Mg deposition layer by hot working (solid recycling)  

Energy Technology Data Exchange (ETDEWEB)

Solid recycling of AZ31 Mg alloy with vapor deposition coating layer of high purity Mg was evaluated. In the open die forging experiments, two AZ31 Mg alloy specimens with the pure Mg layer were sufficiently bonded by forging at 673 K. Furthermore, the Al and Zn of the AZ31 substrate diffused up to the center of the pure Mg layer. By the theoretical analysis, it is suggested that the grain boundary diffusion enhanced by grain refinement due to hot forging contributes to the solid state bonding of the specimens. Also, the solid recycled specimen was fabricated from the AZ31 Mg substrate with pure Mg layer by hot extrusion at 673 K. The solid recycled specimen showed almost the same tensile properties as the virgin extruded specimen. This is probably related not only to the grain boundary diffusion but also severe plastic deformation by hot extrusion. (orig.)

2003-07-01

497

Parametric study of radiative cooling of solid antihydrogen. Master's thesis  

Energy Technology Data Exchange (ETDEWEB)

A computer model of cryogenic system for storing solid antimatter is used to explore the radiative cooling-power requirements for long-term antimatter storage. If vacuum-chamber pressures as low as 10 to -18th power torr can be reached, and the rest of the large set of assumptions is valid, milligram quantities of solid antimatter could be stored indefinitely at 1.5 K using cooling powers of less than a microwatt. Many of the assumptions made are problematic and need verification, as they could potentially change the results greatly. The system modeled is a sphere of solid anti-parahydrogen at 1.5 K or below levitated in a spherical cryogenic vacuum chamber. The free matter gas in the chamber is assumed to be molecular hydrogen, and sublimation of both matter and antimatter is assumed to be negligible. The antihydrogen is assumed to be in thermal equilibrium, although annihilation-energy deposition is localized and ...

1989-03-01

498

A New and Sound Technology for Biogas from Solid Waste and Biomass  

International Nuclear Information System (INIS)

Organic waste, as a main constituent of municipal solid waste, has as well as solid biomass a high potential for biogas generation. Despite the importance of biogas generation from these materials, the availability of large-scale biogas processes lacks behind the demand. A newly developed double-stage solid-liquid biogas process, consisting of an open hydrolysis stage and a fixed-bed methane reactor, allows the biogas production from almost all biodegradable solid waste and renewable resources like maize, grass, sugar cane, etc. Furthermore, residues from industrial processes, like the glycerine waste water from biodiesel production, can also be converted into biogas successfully. Due to the strong separation of hydrolysis and methanation, the process is extremely stable. No malfunction has been detected so far. The open hydrolysis releases CO_2 and allows oxidation of sulfur. Consequently, the biogas ...

2009-04-01

499

ARM: Infrared Thermometer: Ground surface temperature averaged 60-sec at 10-meter height  

Science.gov (United States)

Infrared Thermometer: Ground surface temperature averaged 60-sec at 10-meter height

1996-04-16