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Sample records for spray pyrolysis method

  1. Fabrication of ZnO nanorod using spray-pyrolysis and chemical bath deposition method

    SciTech Connect

    Ramadhani, Muhammad F. Pasaribu, Maruli A. H. Yuliarto, Brian Nugraha

    2014-02-24

    ZnO thin films with nanorod structure were deposited using Ultrasonic Spray Pyrolysis method for seed growth, and Chemical Bath Deposition (CBD) for nanorod growth. High purity Zn-hydrate and Urea are used to control Ph were dissolved in ethanol and aqua bidest in Ultrasonic Spray Pyrolysis process. Glass substrate was placed above the heater plate of reaction chamber, and subsequently sprayed with the range duration of 5, 10 and 20 minutes at the temperatures of 3500 C. As for the Chemical Bath Deposition, the glass substrate with ZnO seed on the surface was immerse to Zn-hydrate, HMTA (Hexa Methylene Tetra Amine) and deionized water solution for duration of 3, 5 and 7 hour and temperatures of 600 C, washed in distilled water, dried, and annealed at 3500 C for an hour. The characterization of samples was carried out to reveal the surface morphology using Scanning Electron Microscopy (SEM). From the data, the combination of 5 minutes of Ultrasonic Spray Pyrolysis process and 3 hour of CBD has showed the best structure of nanorod. Meanwhile the longer Spraying process and CBD yield the bigger nanorod structure that have been made, and it makes the films more dense which make the nanorod collide each other and as a result produce unsymetric nanorod structure.

  2. Method to synthesize and produce thin films by spray pyrolysis

    DOEpatents

    Squillante, Michael R.

    1982-06-22

    Forming a film by spraying onto a heated substrate an atomized solution containing the appropriate salt of a constituent element of the film and a highly soluble (i.e., greater than 1 M) organic acid in sufficient amount to reduce the oxidation state of at least one solute element of the spray solution after contacting the heated substrate.

  3. Method to synthesize and produce thin films by spray pyrolysis

    DOEpatents

    Turcotte, Richard L.

    1982-07-06

    Forming a film by spraying onto a heated substrate an atomized solution containing the appropriate salt of a constituent element of the film and a reducing agent at a concentration greater than 1 M and greater than 10 times the stoichiometric amount of reducing agent.

  4. Nonlinear optical characterization of ZnS thin film synthesized by chemical spray pyrolysis method

    NASA Astrophysics Data System (ADS)

    G, Sreeja V.; V, Sabitha P.; Anila, E. I.; R, Reshmi; John, Manu Punnan; Radhakrishnan, P.

    2014-10-01

    ZnS thin film was prepared by Chemical Spray Pyrolysis (CSP) method. The sample was characterized by X-ray diffraction method and Z scan technique. XRD pattern showed that ZnS thin film has hexagonal structure with an average size of about 5.6nm. The nonlinear optical properties of ZnS thin film was studied by open aperture Z-Scan technique using Q-switched Nd-Yag Laser at 532nm. The Z-scan plot showed that the investigated ZnS thin film has saturable absorption behavior. The nonlinear absorption coefficient and saturation intensity were also estimated.

  5. Nonlinear optical characterization of ZnS thin film synthesized by chemical spray pyrolysis method

    SciTech Connect

    G, Sreeja V; Anila, E. I. R, Reshmi John, Manu Punnan; V, Sabitha P; Radhakrishnan, P.

    2014-10-15

    ZnS thin film was prepared by Chemical Spray Pyrolysis (CSP) method. The sample was characterized by X-ray diffraction method and Z scan technique. XRD pattern showed that ZnS thin film has hexagonal structure with an average size of about 5.6nm. The nonlinear optical properties of ZnS thin film was studied by open aperture Z-Scan technique using Q-switched Nd-Yag Laser at 532nm. The Z-scan plot showed that the investigated ZnS thin film has saturable absorption behavior. The nonlinear absorption coefficient and saturation intensity were also estimated.

  6. Synthesis of Potassium Silicate Nanoparticles from Rice Straw Ash Using a Flame-assisted Spray-pyrolysis Method

    NASA Astrophysics Data System (ADS)

    Nandiyanto, A. B. D.; Permatasari, N.; Sucahya, T. N.; Abdullah, A. G.; Hasanah, L.

    2017-03-01

    The purpose of this study was to synthesize potassium silicate nanoparticles from rice straw ash using a flame-assisted spray-pyrolysis method. Rice straw, as one of the agricultural wastes, was used as a source of silica. In the experimental procedure, rice straw was burned at 700°C for 3 hours to produce rice straw ash. Then, the rice straw ash was extracted using an alkaline method. We used potassium hydroxide (KOH) as an alkaline chemical agent as well as a source of potassium. The solution was then put into the flame-assisted spray-pyrolysis apparatus to produce potassium silicate nanoparticles. The results showed that the spray method can assist the production of spherical potassium silicate nanoparticles with sizes of about 50 nm.

  7. Effects of deposition conditions on the phase formation of YBCO films prepared by spray pyrolysis method

    NASA Astrophysics Data System (ADS)

    Kim, Ho-Jin; Joo, Jinho; Park, Shin-Geun; Hong, Suck-Kwan; Lee, Sun-Wang; Lim, Sun-Weon; Hong, Gye-Won; Lee, Hee-Gyoun

    2006-10-01

    YBa2Cu3Oy superconducting films were deposited on LaAlO3(1 0 0) single crystal substrates by spray pyrolysis method. Two types of ultrasonic and concentric nebulizer were used in order to generate fine droplets of metal-inorganic precursor solution. c-Axis oriented films were obtained at deposition temperature of 750-850 °C and at working pressures of 100 Torr and 500 Torr. In case of ultrasonic nebulizer, the films showed rough surface morphology due to the presence of enormous droplets, whereas smooth and dense films were obtained for concentric nebulizer. The good c-axis oriented YBCO films were formed at the wide range of the oxygen partial pressure. Oxygen which is generated via the decomposition of nitrate precursors is considered to participate in the formation reaction of YBCO film. Microstructures of YBCO films varied depending on oxygen partial pressure and rod-like grains were appeared when the oxygen partial pressure was lower than 30 Torr. YBCO films were deposited epitaxially on LAO(1 0 0) substrate. Δϕ of in-plane and Δω of out-of-plane texture were measured as 3.3° and 1.0°, respectively. A transport Jc value of 0.50 MA/cm2 at 77 K and self-field was achieved for the YBCO film deposited on LaAlO3(1 0 0) single crystal substrate.

  8. Deposition of Ni-CGO composite anodes by electrostatic assisted ultrasonic spray pyrolysis method

    SciTech Connect

    Chen, J.-C.; Chang, C.-L.; Hsu, C.-S.; Hwang, B.-H. . E-mail: zorro@mail.nsysu.edu.tw

    2007-09-04

    Deposition of composite films of Ni and Gd-doped ceria was carried out using the electrostatic assisted ultrasonic spray pyrolysis method for the first time. The composite films were highly homogeneous, as revealed by element mapping via energy-dispersive spectrometry. Scanning electron microscope examinations revealed that deposition temperature and electric field strength had profound influence on resultant microstructure, while composition of the precursor solution had little effect. A highly porous cauliflower structure ideal for solid oxide fuel cell anode performance was obtained with a deposition temperature of 450 deg. C under an electric field introduced by an applied voltage of 12 kV. Films obtained with a lower deposition temperature of 250 deg. C or a higher applied voltage of 15 kV resulted in denser films with low porosity, while lower applied voltages of 7 or 5 kV resulted in thinner or discontinuous films due to the insufficient electrostatic attraction on the aerosol droplets. As revealed by AC impedance measurement, the area specific resistances of the Ni-CGO anode with porous cauliflower structure were rather low and a value of 0.09 {omega} cm{sup 2} at 550 deg. C was obtained.

  9. Photocatalytic Activities of Copper Doped Cadmium Sulfide Microspheres Prepared by a Facile Ultrasonic Spray-Pyrolysis Method.

    PubMed

    Su, Jinzhan; Zhang, Tao; Li, Yufeng; Chen, Yubin; Liu, Maochang

    2016-06-15

    Ultrasonic spray pyrolysis is a superior method for preparing and synthesizing spherical particles of metal oxide or sulfide semiconductors. Cadmium sulfide (CdS) photocatalysts with different sizes and doped-CdS with different dopants and doping levels have been synthesized to study their properties of photocatalytic hydrogen production from water. The CdS photocatalysts were characterized with scanning electron microscopy (SEM), X-ray fluorescence-spectrometry (XRF), UV-Vis absorption spectra and X-ray diffraction (XRD) to study their morphological and optical properties. The sizes of the prepared CdS particles were found to be proportional to the concentration of the metal nitrates in the solution. The CdS photocatalyst with smaller size showed a better photocatalytic activity. In addition, Cu doped CdS were also deposited and their photocatalytic activities were also investigated. Decreased bandgaps of CdS synthesized with this method were found and could be due to high density surface defects originated from Cd vacancies. Incorporating the Cu elements increased the bandgap by taking the position of Cd vacancies and reducing the surface defect states. The optimal Cu-doped level was found to be 0.5 mol % toward hydrogen evolution from aqueous media in the presence of sacrificial electron donors (Na₂S and Na₂SO₃) at a pH of 13.2. This study demonstrated that ultrasonic spray pyrolysis is a feasible approach for large-scale photocatalyst synthesis and corresponding doping modification.

  10. Zinc oxide films prepared by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Maciąg, Andrzej; Sagan, Piotr; Kuźma, Marian; Popovych, Volodymyr

    2016-12-01

    In this work we developed and tested spray pyrolysis system for layers deposition. In the system we have used ultrasonic apparatus (nebulizator) as a sprayer. A zinc nitrate aqueous solution has been used as a precursor solution. The idea of the method is the decomposition of nitrate on a hot substrate according to the reaction Zn(NO3)2 → ZnO +2 NO2 +1/2O2. The layers were grown on glass, (001)Si and KCl substrates at the temperatures 300 - 500°C. The thickness of the obtained layers was in the range 50 - 500 nm, depending on the growth time and rate. The influence of substrate temperature on the morphology of the layers has been studied by SEM method. The energy gap of the layers was found to be the range of 3.26-3.3 eV from their absorption spectra.

  11. Producing Quantum Dots by Spray Pyrolysis

    NASA Technical Reports Server (NTRS)

    Banger, Kulbinder; Jin, Michael H.; Hepp, Aloysius

    2006-01-01

    An improved process for making nanocrystallites, commonly denoted quantum dots (QDs), is based on spray pyrolysis. Unlike the process used heretofore, the improved process is amenable to mass production of either passivated or non-passivated QDs, with computer control to ensure near uniformity of size.

  12. Thin Film Electrode Materials Li4Ti5O12 and LiCoO2 Prepared by Spray Pyrolysis Method

    NASA Astrophysics Data System (ADS)

    Takahashi, M.; Tani, J.; Kido, H.; Hayashi, A.; Tadanaga, K.; Tatsumisago, M.

    2011-05-01

    The Li4Ti5O12 and the LiCoO2 have been considered as promising candidates of electrode materials for all-solid-state lithium secondary batteries. The spray pyrolysis method is a useful economical technique to prepare various thicknesses of oxide films though have not been intensively studied for fabrication of thin film lithium batteries. Thin films of Li4Ti5O12 and LiCoO2 electrode materials about 100-400 nm were prepared on quartz and gold substrates by the spray pyrolysis method by using Liacac and, TiO(acac)4 or Co(acac)3 with DMF solvent as starting materials. Electric properties as electrode materials for lithium batteries were estimated by using 3 probe liquid cells with liquid electrolyte LiPF6 in EC-DMC and Li metal as reference and counter electrodes. Structure and morphology of the films were investigated by XRD and SEM. Crystalline Li4Ti5O12 and LiCoO2 thin films were found to be prepared over 700 °C of substrate temperature. Cyclic voltammograms of the Li4Ti5O12 electrode thin films showed sharp oxidation and reduction peaks around 1.6 and 1.5 V, respectively. Charge-discharge curves for both Li4Ti5O12 and LiCoO2 electrode thin films showed discharge plateaus around 1.4 and 3.8 V with about 80 mAhg-1 of capacity. These results showed that these electrode thin films prepared by the spray pyrolysis method are electrochemically active and spray pyrolysis method is a promising technique to prepare thin film electrode materials.

  13. Mössbauer studies of nanocrystalline ZnFe2O4 particles prepared by spray pyrolysis method

    NASA Astrophysics Data System (ADS)

    Kurian, Jessyamma; John, Subin P.; M, Jacob Mathew; Reddy, V. R.; E, Abraham K.; Prasad, V. S.

    2015-02-01

    This paper reports the synthesis and characterization of nanoparticles of Zn Fe2O4 by spray pyrolysis method. XRD studies indicates that the particle formed are ultra fine (20 nm) associated with strain. The particle size is confirmed by TEM analysis. The room temperature Mossbauer spectrum shows only a doublet which could be indicative of either paramaganetic or superparamagnetic phase. The value of isomer shift is in the range 0.34±0.01 mm/s while quadruple splitting is in the range 0.48±0.01 mm/s. A series of low temperature studies has been performed and the spectra obtained at 20 K and 5K show the presence of two well resolved sextets, which are attributed to the Fe3+ ion in the tetrahedral and octahedral sites of the spinel structure. The application of external magnetic field yields a better fitting resolution of the sub spectra between A and B sites. The temperature dependant and in-field measurements yielded valuable insights about magnetic phase (superparamagnetic), local cation distribution among A sites and B sites, inversion parameter (δ =0.74), canted spin alignment (ψA = 29.58, ψB= 48.46) and the blocking temperature (TB= 50 K).

  14. Porous carbon powders prepared by ultrasonic spray pyrolysis.

    PubMed

    Skrabalak, Sara E; Suslick, Kenneth S

    2006-10-04

    New, thermally robust meso- and macroporous carbon powders were prepared by ultrasonic spray pyrolysis (USP) of aqueous solutions using an inexpensive high-frequency ultrasound generator from a household humidifier. We choose our molecular precursors rationally, so that the expected decomposition pathways produce only remnant carbon atoms. Specifically, our rational design criterion led to halo-organic carboxylate salts, whose pyrolysis yields well-defined carbon solids with a temporary template being generated in situ, simply an inorganic salt, which is easily dissolved during aqueous workup. The materials have been characterized by SEM, TEM, XRD, 13C NMR MAS, XPS, FTIR spectroscopy, and BET surface area measurements. Changing the alkali metal alters the morphology and pore structure of the final material, which can be explained in terms of the observed differences in the DSC and TGA of the various precursors. This preparatory method provides an extremely facile and versatile method for the generation of meso- and macroporous carbons.

  15. Aerosol spray pyrolysis & solution phase synthesis of nanostructures

    NASA Astrophysics Data System (ADS)

    Zhang, Hongwang

    This dissertation focuses on the synthesis of nanomaterials by both solution phase and gas phase methods. By the solution phase method, we demonstrate the synthesis of Au/CdS binary hybrid nanoparticles and the Au-induced growth of CdS nanorods. At higher reaction temperature, extremely uniform CdS nanorods were obtained. The size of the Au seed nanoparticles has an important influence on the length and diameter of the nanorods. In addition, preparation of peanut-like FePt-CdS hybrid nanoparticles by spontaneous epitaxial nucleation and growth of CdS onto FePt-seed nanoparticles in high-temperature organic solution is reported. The FePt-CdS hybrid nanoparticles reported here are an example of a bifunctional nanomaterial that combines size-dependent magnetic and optical properties. In the gas phase method, a spray pyrolysis aerosol synthesis method was used to produce tellurium dioxide nanoparticles and zinc sulfide nanoparticles. Tellurite glasses (amorphous TeO2 based materials) have two useful optical properties, high refractive index and high optical nonlinearity, that make them attractive for a range of applications. In the work presented here, TeO2 nanoparticles were prepared by spray pyrolysis of an aqueous solution of telluric acid, Te(OH)6. This laboratory-scale process is capable of producing up to 80 mg/hr of amorphous TeO2-nanoparticles with primary particle diameters from 10 to 40 nm, and allows their synthesis in significant quantities from an inexpensive and environmentally friendly precursor. Furthermore, both Er3+ doped and Er3+ and Yb3+ co-doped tellurium dioxide nanoparticles were synthesized by spray pyrolysis of an aqueous mixture of telluric acid with erbium/ytterbium salts, which exhibit the infrared to green visible upconversion phenomena. ZnS nanoparticles (NPs) were prepared by spray pyrolysis using zinc diethyldithiocarbamate as a single-source precursor. The home-built scanning mobility particle spectrometer (SMPS) is a useful tool for

  16. Air-assisted ultrasonic spray pyrolysis for nanoparticles synthesis

    NASA Astrophysics Data System (ADS)

    Tsai, Shirley C.; Song, Yu L.; Chen, C. Y.; Tseng, T. K.; Tsai, Chen S.

    2002-11-01

    This paper presents new findings regarding the effects of precursor drop size and concentration on product particle size and morphology in ultrasonic spray pyrolysis of zirconium hydroxyl acetate solutions. Large precursor drops (diameter >30μm) generated by ultrasonic atomization at 120kHz yielded particles with holes. Precursor drops 6-9 μm in diameter, generated by an ultrasonic nebulizer at 1.65MHz and 23.5W electric drive power, yielded uniform spherical particles 150nm in diameter under proper control of heating rate and precursor concentration. Moreover, air-assisted ultrasonic spray pyrolysis at 120kHz and 2.3W yielded spherical particles of which nearly half were smaller than those produced by the ultrasonic spray pyrolysis of the 6-9 μm precursor drops, desprite the much larger precursor drop sizes (28 μm peak diameter versus 7 μm mean diameter). These particles are much smaller than those predicted by the conventional one particle per drop mechanism, suggesting that a vapor condensation mechanism may also be involved in spray pyrolysis. It may be concluded that through this new mechanism air-assisted ultrasonic spray pyrolysis can become a viable process for mass production of nanoparticles.

  17. Photoluminescence of spray pyrolysis deposited ZnO nanorods

    PubMed Central

    2011-01-01

    Photoluminescence of highly structured ZnO layers comprising well-shaped hexagonal rods is presented. The ZnO rods (length 500-1,000 nm, diameter 100-300 nm) were grown in air onto a preheated soda-lime glass (SGL) or ITO/SGL substrate by low-cost chemical spray pyrolysis method using zinc chloride precursor solutions and growth temperatures in the range of 450-550°C. We report the effect of the variation in deposition parameters (substrate type, growth temperature, spray rate, solvent type) on the photoluminescence properties of the spray-deposited ZnO nanorods. A dominant near band edge (NBE) emission is observed at 300 K and at 10 K. High-resolution photoluminescence measurements at 10 K reveal fine structure of the NBE band with the dominant peaks related to the bound exciton transitions. It is found that all studied technological parameters affect the excitonic photoluminescence in ZnO nanorods. PACS: 78.55.Et, 81.15.Rs, 61.46.Km PMID:21711895

  18. Photoluminescence of spray pyrolysis deposited ZnO nanorods

    NASA Astrophysics Data System (ADS)

    Kärber, Erki; Raadik, Taavi; Dedova, Tatjana; Krustok, Jüri; Mere, Arvo; Mikli, Valdek; Krunks, Malle

    2011-04-01

    Photoluminescence of highly structured ZnO layers comprising well-shaped hexagonal rods is presented. The ZnO rods (length 500-1,000 nm, diameter 100-300 nm) were grown in air onto a preheated soda-lime glass (SGL) or ITO/SGL substrate by low-cost chemical spray pyrolysis method using zinc chloride precursor solutions and growth temperatures in the range of 450-550°C. We report the effect of the variation in deposition parameters (substrate type, growth temperature, spray rate, solvent type) on the photoluminescence properties of the spray-deposited ZnO nanorods. A dominant near band edge (NBE) emission is observed at 300 K and at 10 K. High-resolution photoluminescence measurements at 10 K reveal fine structure of the NBE band with the dominant peaks related to the bound exciton transitions. It is found that all studied technological parameters affect the excitonic photoluminescence in ZnO nanorods. PACS: 78.55.Et, 81.15.Rs, 61.46.Km

  19. Photoluminescence of spray pyrolysis deposited ZnO nanorods.

    PubMed

    Kärber, Erki; Raadik, Taavi; Dedova, Tatjana; Krustok, Jüri; Mere, Arvo; Mikli, Valdek; Krunks, Malle

    2011-04-21

    Photoluminescence of highly structured ZnO layers comprising well-shaped hexagonal rods is presented. The ZnO rods (length 500-1,000 nm, diameter 100-300 nm) were grown in air onto a preheated soda-lime glass (SGL) or ITO/SGL substrate by low-cost chemical spray pyrolysis method using zinc chloride precursor solutions and growth temperatures in the range of 450-550°C. We report the effect of the variation in deposition parameters (substrate type, growth temperature, spray rate, solvent type) on the photoluminescence properties of the spray-deposited ZnO nanorods. A dominant near band edge (NBE) emission is observed at 300 K and at 10 K. High-resolution photoluminescence measurements at 10 K reveal fine structure of the NBE band with the dominant peaks related to the bound exciton transitions. It is found that all studied technological parameters affect the excitonic photoluminescence in ZnO nanorods.PACS: 78.55.Et, 81.15.Rs, 61.46.Km.

  20. An easy and innovative method based on spray-pyrolysis deposition to obtain high efficiency cathodes for Solid Oxide Fuel Cells

    NASA Astrophysics Data System (ADS)

    dos Santos-Gómez, L.; Porras-Vázquez, J. M.; Martín, F.; Ramos-Barrado, J. R.; Losilla, E. R.; Marrero-López, D.

    2016-07-01

    A novel electrode preparation method based on the spray-pyrolysis deposition of metal nitrate solutions onto a porous electrolyte scaffold is proposed. This method has been proved with different cathode materials, usually used in Solid Oxide Fuel Cells, such as La0.8Sr0.2MnO3-δ and La0.6Sr0.4Co1-xFexO3-δ (x = 0, 0.2, 0.8 and 1). The electrode microstructure is composed by two layers; the inner layer is a porous electrolyte scaffold homogeneously coated by cathode nanoparticles, providing an increased number of triple phase boundary sites for oxygen reduction, whereas, the top layer is formed by only cathode nanoparticles and acts mainly as a current collector. Polarization resistance values as low as 0.07 and 1.0 Ω cm2 at 600 and 450 °C, respectively, are obtained at open circuit voltage. This alternative approach has several advantages with respect to the traditional wet infiltration method for large area electrode fabrication, such as higher reproducibility, shorter preparation time in a single thermal deposition step, and easy implementation at industrial scale as a continuous process.

  1. Effect of fuel rate and annealing process of LiFePO{sub 4} cathode material for Li-ion batteries synthesized by flame spray pyrolysis method

    SciTech Connect

    Halim, Abdul; Setyawan, Heru; Machmudah, Siti; Nurtono, Tantular; Winardi, Sugeng

    2014-02-24

    In this study the effect of fuel rate and annealing on particle formation of LiFePO{sub 4} as battery cathode using flame spray pyrolysis method was investigated numerically and experimentally. Numerical study was done using ANSYS FLUENT program. In experimentally, LiFePO{sub 4} was synthesized from inorganic aqueous solution followed by annealing. LPG was used as fuel and air was used as oxidizer and carrier gas. Annealing process attempted in inert atmosphere at 700°C for 240 min. Numerical result showed that the increase of fuel rate caused the increase of flame temperature. Microscopic observation using Scanning Electron Microscopy (SEM) revealed that all particles have sphere and polydisperse. Increasing fuel rate caused decreasing particle size and increasing particles crystallinity. This phenomenon attributed to the flame temperature. However, all produced particles still have more amorphous phase. Therefore, annealing needed to increase particles crystallinity. Fourier Transform Infrared (FTIR) analysis showed that all particles have PO4 function group. Increasing fuel rate led to the increase of infrared spectrum absorption corresponding to the increase of particles crystallinity. This result indicated that phosphate group vibrated easily in crystalline phase. From Electrochemical Impedance Spectroscopy (EIS) analysis, annealing can cause the increase of Li{sup +} diffusivity. The diffusivity coefficient of without and with annealing particles were 6.84399×10{sup −10} and 8.59888×10{sup −10} cm{sup 2} s{sup −1}, respectively.

  2. Production and characterization of submicron hematite (α−Fe{sub 2}O{sub 3}) particles by ultrasonic spray pyrolysis method

    SciTech Connect

    Kırcı, Burak; Ebin, Burçak; Gürmen, Sebahattin

    2013-12-16

    The ultrasonic spray pyrolysis (USP) method has been used to prepare submicron hematite (α−Fe{sub 2}O{sub 3}) particles using two different industrial pickling solutions of iron chloride (41 g/L FeCl{sub 2} and 54 g/L FeCl{sub 3}) Particles were obtained by thermal decomposition of generated aerosols from precursor solutions using 1.7 MHz ultrasonic atomizer. Reaction temperature was set up at 800 °C and aerosol droplets were carried into the heated zone by 0.7 L/min air flow rate. X-Ray Diffraction (XRD) studies were used to determine the crystal structure and crystallite size of the particles. Results indicate that patterns correspond to hematite phase with rhombohedral crystal structure (space group: R3c). The crystallite sizes of particles prepared from FeCl{sub 2} and FeCl{sub 3} solutions that were calculated from Scherrer equation are 59 and 33 nm, respectively. Scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) investigations give detailed information about particle size, morphology and composition. SEM micrographs show that hematite nanoparticles aggregate and formed spherical secondary particles in submicron range.

  3. Preparation and characterizations of electroluminescent p-ZnO : N/n-ZnO : Ga/ITO thin films by spray pyrolysis method

    NASA Astrophysics Data System (ADS)

    Panatarani, C.; Fitriyadi, S.; Balasubramanian, N.; Parmar, N. S.; Joni, I. M.

    2016-02-01

    ZnO thin films were fabricated by spray pyrolysis (SP) method with p-ZnO : N/n-ZnO:Ga/ITO structure. The X-ray results show that the deposited films have hexagonal wurtzite structure. The EDS results observed that the composition of Ga in ZnO:Ga and N in ZnO:N was 3.73% and 27.73% respectively. The photoluminescence (PL) with excitation wave length of 260 nm shows that ZnO:Ga and ZnO:N films emitted UV emission at ˜393 and ˜388 nm, respectively and the films resistivity was 7.12 and 12.80 Ohm-cm respectively. The electroluminescence of the p-ZnO : N/n-ZnO:Ga/ITO structure was obtained by applying forward bias of 5 volt with 30 mA current, resulting in a 3.35 volt threshold bias with the peak electroluminescence in UV-blue range.

  4. Effects of ultraviolet light on B-doped CdS thin films prepared by spray pyrolysis method using perfume atomizer

    NASA Astrophysics Data System (ADS)

    Novruzov, V. D.; Keskenler, E. F.; Tomakin, M.; Kahraman, S.; Gorur, O.

    2013-09-01

    Boron doped CdS thin films were deposited by spray pyrolysis method using perfume atomizer. The effects of ultraviolet light on the structural, optical and electrical properties of B-doped CdS thin films were investigated as a function of dopant concentration (B/Cd). X-ray diffraction studies showed that all samples were polycrystalline nature with hexagonal structure. It was determined that the preferred orientation of non-illuminated samples changes from (1 0 1) to (0 0 2) with B concentration. The c lattice constant of films decreases from 6.810 Å to 6.661 Å with boron doping. The XRD peak intensity increased with the illumination for almost all the samples. The lattice parameters of B-doped samples remained nearly constant after illumination. It was found that the optical transmittance, photoluminescence spectra, resistivity and carrier concentration of the B-doped samples are stable after the illumination with UV light. Also the effects of UV light on B-doped CdS/Cu2S solar cell were investigated and it was determined that photoelectrical parameters of B-doped solar cell were more durable against the UV light.

  5. Tailoring of optical band gap by varying Zn content in Cd1-xZnxS thin films prepared by spray pyrolysis method

    NASA Astrophysics Data System (ADS)

    Kumar, Vipin; Sharma, D. K.; Agrawal, Sonalika; Sharma, Kapil K.; Dwivedi, D. K.; Bansal, M. K.

    2016-05-01

    Cd1-XZnXS thin films (X = 0.2, 0.4, 0.6, 0.8) have been grown on glass substrate by spray pyrolysis technique using equimolar concentration aqueous solution of cadmium chloride, zinc acetate and thiourea. Prepared thin films have been characterized by UV-VIS spectrophotometer. The optical band gap of the films has been studied by transmission spectra in wavelength range 325-600nm. It has been observed that optical band gap increases with increasing zinc concentration. The optical band gap of these thin films varies from 2.59 to 3.20eV with increasing Zn content.

  6. Catalytic properties of mesoporous Al–La–Mn oxides prepared via spray pyrolysis

    SciTech Connect

    Kim, Goun; Jung, Kyeong Youl; Lee, Choul-Ho; Han, Jeong-Sik; Jeong, Byung-Hun; Park, Young-Kwon; Jeon, Jong-Ki

    2016-10-15

    Highlights: • Al–La–Mn oxides were prepared using spray pyrolysis. • Al–La–Mn oxides exhibit large and uniform pore sizes. • Mesoporous Al–La–Mn oxides were compared with those prepared by conventional precipitation. • Mesoporous Al–La–Mn oxides show superior activity in decomposition of hydrogen peroxide. - Abstract: Mesoporous Al–La–Mn oxides are prepared via spray pyrolysis and are applied to the catalytic decomposition of hydrogen peroxide. The characteristics of the mesoporous Al–La–Mn oxides are examined using N{sub 2} adsorption, X-ray diffraction, and X-ray fluorescence measurements. The surface area and pore size of the Al–La–Mn oxides prepared via spray pyrolysis are larger than those of the Al–La–Mn oxides prepared using a precipitation method. The catalytic performance of the materials during the decomposition of hydrogen peroxide is examined in a pulse-injection reactor. It is confirmed that the mesoporous Al–La–Mn oxides prepared via spray pyrolysis exhibit higher catalytic activity and stability in the decomposition of hydrogen peroxide than Al–La–Mn oxides prepared using a conventional precipitation method.

  7. Investigations of AlGaN/GaN MOS-HEMT with Al2O3 deposition by ultrasonic spray pyrolysis method

    NASA Astrophysics Data System (ADS)

    Chou, Bo-Yi; Hsu, Wei-Chou; Liu, Han-Yin; Lee, Ching-Sung; Wu, Yu-Sheng; Sun, Wen-Ching; Wei, Sung-Yen; Yu, Sheng-Min; Chiang, Meng-Hsueh

    2015-01-01

    This work investigates Al2O3/AlGaN/GaN metal-oxide-semiconductor high electron mobility transistors (MOS-HEMTs) grown on SiC substrate by using the non-vacuum ultrasonic spray pyrolysis deposition (USPD) method. The Al2O3 was deposited as gate dielectric and surface passivation simultaneously to effectively suppress gate leakage current, enhance output current density, reduce RF drain current collapse, and improve temperature-dependent stabilities performance. The present MOS-HEMT design has shown improved device performances with respect to a Schottky-gate HEMT, including drain-source saturation current density at zero gate bias (IDSS: 337.6 mA mm-1 → 462.9 mA mm-1), gate-voltage swing (GVS: 1.55 V → 2.92 V), two-terminal gate-drain breakdown voltage (BVGD: -103.8 V → -183.5 V), unity-gain cut-off frequency (fT: 11.3 GHz → 17.7 GHz), maximum oscillation frequency (fmax: 14.2 GHz → 19.1 GHz), and power added effective (P.A.E.: 25.1% → 43.6%). The bias conditions for measuring fT and fmax of the studied MOS-HEMT (Schottky-gate HEMT) are VGS = -2.5 (-2) V and VDS = 7 V. The corresponding VGS and VDS biases are -2.5 (-2) V and 15 V for measuring the P.A.E. characteristic. Moreover, small capacitance-voltage (C-V) hysteresis is obtained in the Al2O3-MOS structure by using USPD. Temperature-dependent characteristics of the present designs at 300-480 K are also studied.

  8. Fabrication of functional nanomaterials using flame assisted spray pyrolysis

    SciTech Connect

    Purwanto, Agus

    2014-02-24

    Flame assisted spray pyrolysis (FASP) is a class of synthesis method for nanomaterials fabrication. The ability to control nanomaterials characteristics and easy to be-scaled up are the main features of FASP. The crystallinity and particles size of the prepared nanomaterials can be easily controlled by variation of fuel flow rate. The precursor concentration, carrier gas flow rate, and carrier gas can be also used to control the prepared nanomaterials. Energy related nanomaterials preparation uses as the example case in FASP application. These material are yttrium aluminum garnet (YAG:Ce) and tungsten oxide (WO{sub 3}). It needs strategies to produce these materials into nano-sized order. YAG:Ce nanoparticles only can be synthesized by FASP using the urea addition. The decomposition of urea under high temperature of flame promotes the breakage of YAG:Ce particles into nanoparticles. In the preparation of WO{sub 3}, the high temperature flame can be used to gasify WO{sub 3} solid material. As a result, WO{sub 3} nanoparticles can be prepared easily. Generally, to produce nanoparticles via FASP method, the boiling point of the material is important to determine the strategy which will be used.

  9. Spray Pyrolysis as a Synthetic Tool.

    DTIC Science & Technology

    1984-11-01

    tetracyclic system (84) (40%) m.p. > 350*C (Lit. 40> 3300C). I+ S’ 0 S 45. References 1. Azidoformates were prepared by the method of L.A. Caprino , B.A... Caprino , C.A. Giz, R.N. Murray, A.A. Santilli, and P.H. Terry, Organic Synthesis, 1973, Coil. Vol , p.168. 2. R.K. Smalley, ’Azepines’ in

  10. Generation of size-monodisperse metal nanoparticles by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Kim, Jung Hyeun

    2003-10-01

    Size-monodisperse pure copper metal particles were formed from metal salt precursors in a spray pyrolysis process that uses ethanol as a co-solvent, thus avoiding the addition of hydrogen or other reducing gases. In addition, the uniform-size particles were classified using a droplet impactor plate, which eliminates larger droplets at the atomizer prior to entering the reactor furnace. To investigate the role of ethanol co-solvent for the formation of phase pure metal particles in the spray pyrolysis process, the generation of phase pure copper and nickel particles from aqueous solutions of copper acetate, copper nitrate, and nickel nitrates over the temperature range of 450°C to 1000°C was demonstrated. Addition of ethanol as a co-solvent played a crucial role in producing phase pure metal powders. Results of a modeling study of ethanol decomposition kinetics suggested that co-solvent decomposition created a strong reducing atmosphere during spray pyrolysis via in-situ production of hydrogen and carbon monoxide. With the size-classified copper spheres as well as monodisperse polystyrene latex (PSL) spheres, the polarization and intensity of light scattered by those spheres, having diameters ranging from 92 nm to 218 nm, deposited on silicon substrates were measured using 442 nm, 532 nm, and 633 nm light. The results showed that accurate calculation of the scattering of light by a metal sphere requires that the near-field interaction between the sphere and its image is included in a complete manner. The normal incidence approximation did not suffice for this interaction, and the existence of any thin oxide layer on the substrate must be included in the calculation. In order to further examine the effects of light scattering by particles on a silicon substrate having an oxide coating, the polarization and intensity of light scattered by 101 nm polystyrene latex (PSL) and 100 nm copper spheres, deposited on silicon substrates containing various thickness of oxide

  11. Magnetic and porous nanospheres from ultrasonic spray pyrolysis.

    PubMed

    Suh, Won Hyuk; Suslick, Kenneth S

    2005-08-31

    We have used an inexpensive high-frequency ultrasound generator from a household humidifier to create a useful source for ultrasonic spray pyrolysis and produced submicrometer silica particles that are porous on the nanometer scale. By using two heated zones, we first initiate polymerization of organic monomers in the presence of silica colloid, which creates in situ a composite of silica with an organic polymer, followed by a second heating to pyrolyze and remove the polymer. The morphology and surface area of the final porous silica are controlled by varying the silica-to-organic monomer ratio. In a single flow process, ferromagnetic cobalt nanoparticles can be easily encapsulated in the porous silica, and the resulting nanospheres are extremely resistant to air oxidation. Products were characterized by SEM, (S)TEM, EDS, XPS, and SQUID.

  12. SnS2 Thin Film Deposition by Spray Pyrolysis

    NASA Astrophysics Data System (ADS)

    Jaber, Abdallah Yahia; Alamri, Saleh Noaiman; Aida, Mohammed Salah

    2012-06-01

    Tin disulfide (SnS2) thin films have been synthesized using a simplified spray pyrolysis technique using a perfume atomizer. The films were deposited using two different solutions prepared by the dilution of SnCl2 and thiourea in distilled water and in methanol. The obtained films have a microcrystalline structure. The film deposited using methanol as the solvent is nearly stochiometric SnS2 with a spinel phase having a (001) preferential orientation. The film prepared with an aqueous solution is Sn-rich. Scanning electronic microscopy (SEM) images reveal that the film deposited with the aqueous solution is rough and is formed with large wires. However, the film deposited with methanol is dense and smooth. Conductivity measurements indicate that the aqueous solution leads to an n-type semiconductor, while methanol leads to a p-type semiconductor.

  13. Titania by spray pyrolysis for photocatalytic destruction of organics in aqueous solutions

    SciTech Connect

    Fotou, G.P.; Himebaugh, L.; Kodas, T.T.; Wu, M.

    1996-12-31

    In this study, the potential of spray pyrolysis and spray calcination for the synthesis of effective titanium dioxide photocatalysts is explored. The product titanium dioxide powders were used in the photoassisted oxidation of salicylic acid in aqueous solutions. Titania particles were produced by spray pyrolysis of dihydroxybis titanium solutions in water at concentrations between 20 to 70% by volume at temperatures from 500 to 1100{degrees}C. Powders were made by spray calcination of titanium hydrolysate solutions at temperatures from 700 to 900 {degrees}C. Spray pyrolysis produced titania particles which were partially hollow. Spray calcination resulted in agglomerates which consisted of 15 nm primary particles that showed high photoactivity in the photooxidation of aqueous salicylic acid solutions. Doping with palladium oxide or ruthenium oxides did not improve the photocatalytic activity of these powders. 6 refs., 3 figs.

  14. A newly designed ultrasonic spray pyrolysis device to fabricate YBCO tapes

    NASA Astrophysics Data System (ADS)

    Liu, M.; Zhou, M. L.; Zhai, L. H.; Liu, D. M.; Gao, X.; Liu, W.

    2003-04-01

    A newly designed ultrasonic spray pyrolysis device has been manufactured to fabricate YBCO tapes. The apparatus is primarily composed of four zones: the ultrasonic generator, the atomization chamber, the pyrolysis chamber and the rotating equipment. Every part of them is designed and fabricated by us. The whole system costs far less than the ready-made equipment facility in which there is always a vacuum apparatus. This apparatus with processing parameters accurately controlled can fabricate short and long YBCO tapes. In this paper, we mainly focused on how to design and manufacture four parts of the ultrasonic spray pyrolysis. We have deposited c-axis aligned short YBCO tapes on biaxially textured Ag {1 1 0}<1 1 0> substrates with Jc=10 3 A/cm 2 using this method with our device. The method is very promising in terms of its precise control of metal compositions, high deposition rate and low cost non-vacuum approach. Improvements of this technique are being carried out to fabricate long YBCO tapes.

  15. ZnO layers prepared by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Messaoudi, C.; Abd-Lefdil, S.; Sayah, D.; Cadene, M.

    1998-02-01

    Highly transparent undoped and indium doped ZnO thin films have been grown on glass substrates by using the spray pyrolysis process. Conditions of preparation have been optimized to get good quality and reproducible films with required properties. Polycrystalline films with an hexagonal Wurtzite-type structure were easily obtained under the optimum spraying conditions. Both of samples have shown high transmission coefficient in the visible and infrared wavelength range with sharp absorption edge around 380 nm which closely corresponds to the intrinsic band-gap of ZnO (3.2 eV). Orientation and crystallites size were remarkably modified by deposition temperature and indium doping. Des couches minces de ZnO, hautement transparentes, non dopées et dopées à l'indium ont été élaborées sur un substrat en verre par le procédé de pulvérisation chimique réactive spray. Les conditions de préparation ont été optimisées pour l'obtention de couches reproductibles, de bonne qualité et ayant les propriétés requises. Des films polycristallins, présentant une structure hexagonale de type Wurtzite, ont été aisément obtenus dans les conditions optimales de pulvérisation. Tous les échantillons ont présenté un coefficient de transmission élevé dans le domaine du visible et du proche infrarouge, avec une absorption brutale au voisinage de 380 nm, correspondant au gap optique du ZnO (3,2 eV). L'orientation et la taille des cristallites ont été remarquablement modifiées par la température du dépôt et par le dopage à l'indium.

  16. Preparation of oxide particles with ordered macropores by colloidal templating and spray pyrolysis

    SciTech Connect

    Abdullah, Mikrajuddin; Iskandar, Ferry; Shibamoto, Shinji; Ogi, Takashi; Okuyama, Kikuo . E-mail: okuyama@hiroshima-u.ac.jp

    2004-10-04

    Silicon dioxide, titanium dioxide, aluminium dioxide, zirconium dioxide, and yttrium dioxide particles containing macropores with ordered, hexagonal closed packing structures were produced by spray pyrolysis. A mixture of a solution of the oxide source (nitrous metal) and a colloid comprised of polystyrene latex (PSL) particles was used. The process involved initial drying at low temperature to evaporate the solvent, followed by drying at high temperature to permit the pyrolysis reaction to occur and to decompose the PSL beads. This takes place in a vertical reactor and requires around 1-2 s. This method can, in principle, be used to produce various types of oxide particles containing ordered pores. It allows easy control of the particle size, pore size and space, and the porosity of particles. Bragg reflection of the powdered material was observed under ultraviolet irradiation.

  17. In-situ fabrication of nanostructured cobalt oxide powders by spray pyrolysis technique.

    PubMed

    Zhao, Z W; Konstantinov, K; Yuan, L; Liu, H K; Dou, S X

    2004-09-01

    Nano-crystalline Co3O4 and CoO powders have been prepared by a spray pyrolysis approach. The effects of the reaction temperature and initial salts on the crystallinity and phase composition have been studied. Based on the TEM and XRD results, the crystal sizes were in the range of 1-10 nm. SEM and TEM observations also reveal that the nano-powders easily create micron-scale spherical agglomerates. The Co3O4 powders obtained by spraying nitrate solution at 500 degrees C show high specific surface area, which according to the BET method is 82.37 m2/g. The time/temperature phase diagram of cobalt oxides developed from XRD and DTA/TGA analyses shows the existence of a CoO phase at low and high temperature ranges when some specific preparation conditions are applied.

  18. Cytotoxicity of gold nanoparticles prepared by ultrasonic spray pyrolysis.

    PubMed

    Rudolf, R; Friedrich, B; Stopić, S; Anžel, I; Tomić, S; Čolić, M

    2012-01-01

    The aim of this work was to study the cytotoxicity of different fractions of gold nanoparticles prepared by ultrasonic spray pyrolysis from gold scrap. The target cells were rat thymocytes, as a type of nonproliferating cells, and L929 mouse fibroblasts, as a type of continuous proliferating cells. Fractions 1 and 2, composed of pure gold nanoparticles, as determined by scanning electron microscopy with a combination of energy dispersive X-ray analysis, were nontoxic for thymocytes, but reduced moderately the proliferative activity of L929 cells. The inhibitory effect of fraction 2, containing particles smaller in size than fraction 1, was stronger. Fraction 3, composed of Au and up to 3% Cu was noncytotoxic for thymocytes, but was cytotoxic for L929 cells. Fraction 4, composed of Au and Ag nanoparticles, and fraction 5, composed of Au together with Cu, Ni, Zn, Fe, and In were cytotoxic for both thymocytes and L929 cells. These results suggest that USP enables the synthesis of pure gold nanoparticles with controlled size, even from gold scrap. However, microstructural analyses and biocompatibility testing are necessary for their proper selection from more cytotoxic gold nanoparticles, contaminated with other elements of gold alloys.

  19. Decoration of crumpled rGO sheets with Ag nanoparticles by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Papailias, I.; Giannouri, M.; Trapalis, A.; Todorova, N.; Giannakopoulou, T.; Boukos, N.; Lekakou, C.

    2015-12-01

    In this work, crumpled reduced graphene oxide (rGO) nanostructures were produced using spray pyrolysis technique. Graphite oxide (GtO) prepared through a modified Hummers method was used as starting material. Water dispersions of graphene oxide (GO) were prepared and sprayed in a tube furnace at 300 °C, 500 °C and 700 °C using Argon (Ar) as carrier gas. Also, precursor dispersions with different AgNO3 concentrations were processed at the same conditions. During the treatment, the sprayed droplets underwent rapid heating and then gradual cooling until the exit of the oven, where crumpled rGO and Ag/rGO powders were collected. The prepared materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman and FT-IR spectroscopy. It was established that the crumpling of the nanosheets was slightly affected by the increase of the process temperature. Crumpled morphologies were obtained even at low temperature of 300 °C. In contrast, the degree of GO reduction was temperature dependent and increased with the increase of the temperature. The incorporation of Ag nanoparticles was evidenced by the XRD and TEM analysis with the size of the Ag nanoparticles to grow as the concentration of AgNO3 and/or the process temperature increased. SERS effect in the Raman spectra of the Ag/rGO materials was observed that reached a maximum at 500 °C. Spray pyrolysis was suggested as a simple, controllable and scalable route for the instantaneous crumpling, reduction and decoration of GO nanosheets with metal/metal oxide nanoparticles.

  20. Effect of precursor concentration and spray pyrolysis temperature upon hydroxyapatite particle size and density.

    PubMed

    Cho, Jung Sang; Lee, Jeong-Cheol; Rhee, Sang-Hoon

    2016-02-01

    In the synthesis of hydroxyapatite powders by spray pyrolysis, control of the particle size was investigated by varying the initial concentration of the precursor solution and the pyrolysis temperature. Calcium phosphate solutions (Ca/P ratio of 1.67) with a range of concentrations from 0.1 to 2.0 mol/L were prepared by dissolving calcium nitrate tetrahydrate and diammonium hydrogen phosphate in deionized water and subsequently adding nitric acid. Hydroxyapatite powders were then synthesized by spray pyrolysis at 900°C and at 1500°C, using these calcium phosphate precursor solutions, under the fixed carrier gas flow rate of 10 L/min. The particle size decreased as the precursor concentration decreased and the spray pyrolysis temperature increased. Sinterability tests conducted at 1100°C for 1 h showed that the smaller and denser the particles were, the higher the relative densities were of sintered hydroxyapatite disks formed from these particles. The practical implication of these results is that highly sinterable small and dense hydroxyapatite particles can be synthesized by means of spray pyrolysis using a low-concentration precursor solution and a high pyrolysis temperature under a fixed carrier gas flow rate.

  1. Fabrication of CIGS thin films by using spray pyrolysis and post-selenization

    NASA Astrophysics Data System (ADS)

    Kim, Seong Yeon; Kim, JunHo

    2012-06-01

    We fabricated Cu(In1- x Ga x )Se2 ( x: 0 ˜ 0.4) thin films by using ultrasonic spray pyrolysis and post-selenization. First, we made Cu(In1- x Ga x )S2 ( x: 0 ˜ 0.4) films by ultrasonic spray pyrolysis under an air environment. Then, we converted as-sprayed Cu(In1- x Ga x )S2 (CIGS) films to Cu-(In1- x Ga x )Se2 (CIGSe) films through post-selenization. For all Ga fractions, the sprayed CIGS films were well recrystallized into poly-crystalline CIGSe films with a dominant (112) texture, which was confirmed by X-ray diffraction, Raman spectroscopy and energy dispersive X-ray analyses. This result indicates that CIGSe films with any amount of Ga substitution can be made by converting sprayed CIGS to CIGSe with post-selenization.

  2. Methods and apparatuses for preparing upgraded pyrolysis oil

    DOEpatents

    Brandvold, Timothy A; Baird, Lance Awender; Frey, Stanley Joseph

    2013-10-01

    Methods and apparatuses for preparing upgraded pyrolysis oil are provided herein. In an embodiment, a method of preparing upgraded pyrolysis oil includes providing a biomass-derived pyrolysis oil stream having an original oxygen content. The biomass-derived pyrolysis oil stream is hydrodeoxygenated under catalysis in the presence of hydrogen to form a hydrodeoxygenated pyrolysis oil stream comprising a cyclic paraffin component. At least a portion of the hydrodeoxygenated pyrolysis oil stream is dehydrogenated under catalysis to form the upgraded pyrolysis oil.

  3. Synthesis and characterization of ZnO nano and micro structures grown by low temperature spray pyrolysis and vapor transport.

    PubMed

    Agouram, S; Bushiri, M J; Montenegro, D N; Reig, C; Martínez-Tomás, M C; Muñoz-Sanjosé, V

    2012-08-01

    In this work we present a systematic study of ZnO micro and nanostructures grown by spray pyrolysis (SP) and by physical vapour transport (PVT) on glass and c-sapphire substrates at low temperatures. Optimised growth conditions have allowed to obtain homogeneous ZnO nanolayers composed of quasi-spherical nanoparticles in the range 2 to 8 nm by spray pyrolysis, while by PVT the selected growth conditions allow to produce a wide variety of morphologies (tripods, grains, arrows and wires) of nano and microsize dimension. Grazing incidence X-ray diffraction, field emission scanning electron microscopy (FE-SEM), high resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED) and energy dispersive X-ray spectroscopy (EDX) were used as characterization techniques in the investigation of structural, morphological and compositional nature of these nanostructures in relation with the growth method.

  4. Synthesis of TiO{sub 2} core/RuO{sub 2} shell particles using multistep ultrasonic spray pyrolysis

    SciTech Connect

    Stopic, Srecko; Friedrich, Bernd; Schroeder, Michael; Weirich, Thomas E.

    2013-09-01

    Graphical abstract: - Highlights: • TiO{sub 2} core/RuO{sub 2} shell submicron-particles were prepared via a sequential spray pyrolysis. • Spherical particles have the mean particle diameters between 200 and 400 nm. • This method is promising for synthesis of core–shell and core–multishell materials. - Abstract: Spherical submicron-particles with TiO{sub 2} core–RuO{sub 2} shell structure have been synthesized by employing sequential ultrasonic spray pyrolysis. The particles have been investigated by X-ray powder diffraction, scanning electron microscopy and different transmission electron microscopy techniques. The quality of the core–shell structure of the particles has been confirmed by comparison of the experimental data with those generated on the basis of a hard sphere core–shell model. It has been found that the mixing of the Ru-containing aerosol with the TiO{sub 2} particle stream has a significant impact on the core–shell formation. The method introduced in this study can probably be applied for preparation of core–shell and core–multishell materials that are difficult to synthesize in a single step spray pyrolysis process.

  5. Growth of ZnO rods on FTO electrodes by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Dedova, Tatjana; Volobujeva, Olga; Krunks, Malle; Mikli, Valdek; Gromyko, Inga; Katerski, Atanas; Mere, Arvo

    2013-12-01

    ZnO layers comprizing rods were deposited by chemical spray pyrolysis (CSP) method at 520 °C on different FTO (SnO2:F)/glass substrates using zinc chloride aqueous solutions. Substrates were purchased from different manufactures and differ by morphology, grain size and roughness of FTO electrode. FTO/glass substrates and ZnO layers grown on them were characterised with the help of XRD, AFM, high resolution SEM, EDX methods. The relationship between nanorod formation and substrate properties was studied. It was found that substrate roughness and grain size influence the ZnO rods formation. Deposition of rods (d=300 nm, L=1.4 μm) was successful on the FTO layers with grain sizes around 30-50 nm and roughness below 10 nm, whereas large-grained FTO (grain size > 130 nm) resulted in thick, low-aspect ratio crystals with diameter around 400 nm and length of about 400 nm.

  6. Computational fluid dynamic modeling of the flame spray pyrolysis process for silica nanopowder synthesis

    NASA Astrophysics Data System (ADS)

    Olivas-Martinez, Miguel; Sohn, Hong Yong; Jang, Hee Dong; Rhee, Kang-In

    2015-07-01

    A computational fluid dynamic model that couples the fluid dynamics with various processes involving precursor droplets and product particles during the flame spray pyrolysis (FSP) synthesis of silica nanopowder from volatile precursors is presented. The synthesis of silica nanopowder from tetraethylorthosilicate and tetramethylorthosilicate in bench- and pilot-scale FSP reactors, with the ultimate purpose of industrial-scale production, was simulated. The transport and evaporation of liquid droplets are simulated from the Lagrangian viewpoint. The quadrature method of moments is used to solve the population balance equation for particles undergoing homogeneous nucleation and Brownian collision. The nucleation rate is computed based on the rates of thermal decomposition and oxidation of the precursor with no adjustable parameters. The computed results show that the model is capable of reproducing the magnitude as well as the variations of the average particle diameter with different experimental conditions using a single value of the collision efficiency factor α for a given reactor size.

  7. Characterization of CuO Thin Films Deposition on Porous Silicon by Spray Pyrolysis

    NASA Astrophysics Data System (ADS)

    Khashan, Khawla S.; Hassan, Azhar I.; Addie, Ali J.

    2016-05-01

    CuO thin films on porous silicon (PSi) substrates were prepared via spray pyrolysis method. The structural, optical and electrical properties of the films and the heterojunctions were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscope (AFM) and UV-Vis spectrophotometer. XRD results show that the film is polycrystalline and have a monoclinic crystal structure. Optical measurement indicates that the films had a low transmittance at the visible range and an optical bandgap of 2.2eV. High rectification was achieved with a maximum photoresponsivity of about 0.59A/W at 400nm, so that the CuO/PSi heterojunction may act as a good candidate for the fabrication of an efficient photodiode.

  8. Gallium doping in transparent conductive ZnO thin films prepared by chemical spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Babar, A. R.; Deshamukh, P. R.; Deokate, R. J.; Haranath, D.; Bhosale, C. H.; Rajpure, K. Y.

    2008-07-01

    Zinc oxide (ZnO) and ZnO : Ga films have been deposited by the spray pyrolysis method onto preheated glass substrates using zinc acetate and gallium nitrate as precursors for Zn and Ga ions, respectively. The effect of Ga doping on the structural, morphological, optical and electrical properties of sprayed ZnO thin films were investigated using x-ray diffraction (XRD), scanning electron microscopy, optical absorption, photoluminescence (PL) and Hall effect techniques. XRD studies reveal that films are polycrystalline with hexagonal (wurtzite) crystal structure. The thin films were oriented along the (0 0 2) plane. Room temperature PL measurements indicate that the deposited films exhibit proper doping of Ga in ZnO lattice. The average transparency in the visible range was around ~85-95% for typical thin film deposited using 2 at% gallium doping. The optical band gap increased from 3.31 to 3.34 eV with Ga doping of 2 at%. The addition of gallium induces a decrease in electrical resistivity of the ZnO : Ga films up to 2 at% gallium doping. The highest figure of merit observed in this present study was 3.09 × 10-3 cm2 Ω-1.

  9. Thin films of SiO2 and hydroxyapatite on titanium deposited by spray pyrolysis.

    PubMed

    Jokanovic, V; Jokanovic, B; Izvonar, D; Dacic, B

    2008-05-01

    Wet spray pyrolysis of fine, well-dispersed a SiO2 sol was used for the deposition of thin films of silicon dioxide. The sol was obtained by hydrothermal precipitation of silicon acid from a solution at pH = 10. The morphology, roughness, phase composition, chemical homogeneity and the mechanism of the films were investigated by SEM, EDS and IR spectroscopy. The obtained results show a complete covering of the titanium substrate with SiO2 after 3 h of deposition. It was observed that the film thickness increased from 3 to 19 microm, the roughness of the film decreased from 12 to 3 microm, while the morphology of the deposit changed considerably. A hydroxyapatite film was prepared on the so-obtained SiO2 thin film by spray pyrolysis deposition and its morphology and phase composition were investigated.

  10. Zirconium doped TiO2 thin films deposited by chemical spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Juma, A.; Oja Acik, I.; Oluwabi, A. T.; Mere, A.; Mikli, V.; Danilson, M.; Krunks, M.

    2016-11-01

    Chemical spray pyrolysis (CSP) is a flexible deposition technique that allows for mixing of the precursor solutions in different proportions suitable for doping thin films. The CSP method was used to dope TiO2 thin films with Zr by adding zirconium(IV) acetylacetonate into a solution of titanium(IV) isopropoxide in ethanol stabilized by acetylacetone at [Zr]/[Ti] of 0, 5, 10 and 20 at%. The Zr-doped TiO2 thin films were uniform and homogeneous showing much smaller grains than the undoped TiO2 films. Zr stabilized the anatase phase to temperatures above 800 °C depending on Zr concentration in the spray solution. The concentration of Zr determined by XPS was 6.4 at% for the thin film deposited from the 20 at% solution. According to AFM studies, Zr doping decreased the root mean square roughness of TiO2 film from 5.9 to 1.1 nm. An XRD study of samples with the highest Zr amount showed the ZrTiO4 phase started forming after annealing at 800 °C. The optical band gap for TiO2 decreased from 3.3 eV to 3.0 eV after annealing at 800 °C but for the TiO2:Zr(20) film it remained at 3.4 eV. The dielectric constant increased by more than four times with Zr-doping and this was associated with the change in the bond formations caused by substitution of Ti by Zr in the lattice.

  11. Electrical and optical properties of Al doped Zno film prepared by spray pyrolysis technique

    NASA Astrophysics Data System (ADS)

    Shrestha, Shankar Prasad; Basnet, Pradeep

    2008-04-01

    Transparent conducting thin films of zinc oxides and aluminum doped zinc oxide (AZO) were prepared by the spray pyrolysis technique using an aqueous solution of dehydrate zinc acetate (CH 3COOH. 2H IIO, pure- Merck A. R. grade) and hex hydrate aluminum chloride (AlCl 3 .6H IIO) on the micro glass slides. The prepared thin films are found to be highly adherent to the substrate and possess uniform conduction. The optical and electrical properties of the film were investigated in terms of different Al concentration in the starting solution and different substrate temperature. Four probe method in Van der pauw configuration was used for electrical resistivity measurements. The resistivity of Al doped film is observed to vary with doping concentration. The lowest resistivity is observed in the film doping with 2 at % [Al/Zn]. The Hall coefficient measurements show that both ZnO and AZO show the n-type conduction. The carrier concentration was observed to be highest at 2 at% of Al doping. The optical measurements of all the samples with aluminum concentrations was found to be >85 % showing the film to be highly transparent in nature. With increase in Al concentration, the optical band gap was observed increase from 3.27 eV to 3.41 eV.

  12. Conductivity study of nitrogen-doped calcium zinc oxide prepared by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Hsu, Yu-Ting; Lan, Wen-How; Huang, Kai-Feng; Lin, Jia-Ching; Chang, Kuo-Jen

    2016-01-01

    In this study, the spray pyrolysis method was used to prepare unintentionally doped and nitrogen-doped calcium zinc oxide films by using zinc acetate, calcium nitrate precursor, and ammonium acetate precursor. Morphological and structural analyses were conducted using scanning electron microscopy and X-ray diffraction. The results indicated that film grain size decreased as the nitrogen doping was increased. Both calcium oxide and zinc oxide structures were identified in the unintentionally doped calcium zinc oxide. When nitrogen doping was introduced, the film mainly exhibited a zinc oxide structure with preferred (002) and (101) orientations. The concentration and mobility were investigated using a Hall measurement system. P-type films with a mobility and concentration of 10.6 cm2 V-1 s-1 and 2.8×1017 cm-3, respectively, were obtained. Moreover, according to a temperature-dependent conductivity analysis, an acceptor state with activation energy 0.266 eV dominated the p-type conduction for the unintentionally doped calcium zinc oxide. By contrast, a grain boundary with a barrier height of 0.274-0.292 eV dominated the hole conduction for the nitrogen-doped calcium zinc oxide films.

  13. Amorphous Molybdenum Sulfide/Carbon Nanotubes Hybrid Nanospheres Prepared by Ultrasonic Spray Pyrolysis for Electrocatalytic Hydrogen Evolution.

    PubMed

    Ye, Zhifeng; Yang, Jia; Li, Bo; Shi, Lei; Ji, Hengxing; Song, Li; Xu, Hangxun

    2017-04-11

    Developing cost-effective electrocatalysts with high activity and stability for hydrogen evolution reaction (HER) plays an important role in modern hydrogen economy. Amorphous molybdenum sulfide (MoSx ) has recently emerged as one of the most promising alternatives to Pt-based catalysts in HER, especially in acidic electrolytes. Here this study reports a simple ultrasonic spray pyrolysis method to synthesize hybrid HER catalysts composed of MoSx firmly attached on entangled carbon nanotube nanospheres (MoSx /CNTs). This synthetic process is fast, continuous, highly durable, and amenable to high-volume production with high yields and exceptional quality. The MoSx /CNTs hybrid catalyst prepared at 300 °C exhibits a low overpotential of 168 mV at the current density of 10 mA cm(-2) with a small Tafel slope of 36 mV dec(-1) . Electrochemical measurements and X-ray photoelectron spectroscopy analyses reveal that the CNT network not only promotes the charge transfer in corresponding HER process but also enhances the stability of the active sites in MoSx . This work demonstrates that ultrasonic spray pyrolysis is a reliable and versatile approach for synthesizing amorphous MoSx -based HER catalysts.

  14. Achieving Low-Electrical-Resistance WO3:Li Nanostructured Thin Films Using Spray Pyrolysis Technique

    NASA Astrophysics Data System (ADS)

    Asghari, Zahra; Eshghi, Hosein

    2017-03-01

    We have grown 1 wt.%, 5 wt.%, and 10 wt.% Li-doped tungsten oxide thin films on glass substrate using the spray pyrolysis technique and investigated their morphological, structural, optical, and electrical properties. In addition to formation of nanograin coverage, we found that the doped films grew with polycrystalline monoclinic structure having preferred orientation along (200) plane instead of the amorphous undoped structure. The 10 wt.%-doped sample showed the highest visible transmittance (˜95%) and lowest resistivity (˜7.5 Ω cm), together with relatively high ultraviolet (UV) photoluminescence emission at room temperature.

  15. Hydroxyapatite forming ability of electrostatic spray pyrolysis derived calcium phosphate nano powder.

    PubMed

    Hwang, Kyu-Seog; Jeon, Kyung-Ok; Jeon, Young-Sun; Kim, Byung-Hoon

    2007-04-01

    A novel fabrication technique, i.e., electrostatic spray pyrolysis (ESP), has been used in this study to prepare calcium phosphate nano powders. Final annealing was done at 400 degrees C for 30 min in air. The hydroxyapatite-forming ability of the annealed powder has been investigated in Eagle's minimum essential medium solution. X-ray diffracton, field emission scanning electron microscope, energy dispersive X-ray spectroscope, and Fourier transform infrared spectroscope were employed to characterize the annealed powders after immersion. The powder with an amorphous structure induced hydroxyapatite formation on their surfaces after immersion for 15 days.

  16. Thin Film CuInS2 Prepared by Spray Pyrolysis with Single-Source Precursors

    NASA Technical Reports Server (NTRS)

    Jin, Michael H.; Banger, Kulinder K.; Harris, Jerry D.; Cowen, Jonathan E.; Hepp, Aloysius F.; Lyons, Valerie (Technical Monitor)

    2002-01-01

    Both horizontal hot-wall and vertical cold-wall atmospheric chemical spray pyrolysis processes deposited near single-phase stoichiometric CuInS2 thin films. Single-source precursors developed for ternary chalcopyrite materials were used for this study, and a new liquid phase single-source precursor was tested with a vertical cold-wall reactor. The depositions were carried out under an argon atmosphere, and the substrate temperature was kept at 400 C. Columnar grain structure was obtained with vapor deposition, and the granular structure was obtained with (liquid) droplet deposition. Conductive films were deposited with planar electrical resistivities ranging from 1 to 30 Omega x cm.

  17. Study of photoconductivity in Ni doped CdS thin films prepared by spray pyrolysis technique

    SciTech Connect

    Patidar, Manju Mishra Gangrade, Mohan; Nath, R.; Ganesan, V.; Ajay, Akhil; Wala, Arwa Dewas; N, Kiran; Panda, Richa

    2014-04-24

    Ni-doped cadmium sulphide [Cd{sub 1−x}Ni{sub x}S, (x=0, 0.03, 0.05 and 0.20)] thin films were investigated for photoconductive properties. The films were prepared by spray Pyrolysis technique (SPT). AFM and two probe resistivity measurements were carried out to analyze the morphological and electrical properties of the films. AFM shows the note worthy changes in the morphology where the nanorod structures in CdS is changed into nano particles with the Ni doping. The presence of persistence photo current is demonstrated and extensive photoconductivity analysis has been studied on these films.

  18. Structural and optical characterization of InAs nanocrystals deposited by spray pyrolysis

    SciTech Connect

    Mousa, A. M. Mohammed, M. A.; Kadhim, R.

    2015-03-30

    4-5 nm size InAs nanocrystals were prepared by spray pyrolysis technique on glass substrates from alkaline solution containing InCl{sub 3} and As{sub 2}O. X-Ray diffraction and absorption spectra suggested that the deposition conditions (deposition time and temperature) had a profound influence on the structure and thickness of deposited layers. The optical absorption band edges shifted to lower energy when increasing the thickness with respect to the bulk material. The marked blue shift of the optical absorption edge indicated a strong quantum confinement effect in InAs films.

  19. Achieving Low-Electrical-Resistance WO3:Li Nanostructured Thin Films Using Spray Pyrolysis Technique

    NASA Astrophysics Data System (ADS)

    Asghari, Zahra; Eshghi, Hosein

    2016-12-01

    We have grown 1 wt.%, 5 wt.%, and 10 wt.% Li-doped tungsten oxide thin films on glass substrate using the spray pyrolysis technique and investigated their morphological, structural, optical, and electrical properties. In addition to formation of nanograin coverage, we found that the doped films grew with polycrystalline monoclinic structure having preferred orientation along (200) plane instead of the amorphous undoped structure. The 10 wt.%-doped sample showed the highest visible transmittance (˜95%) and lowest resistivity (˜7.5 Ω cm), together with relatively high ultraviolet (UV) photoluminescence emission at room temperature.

  20. Properties of mixed molybdenum oxide iridium oxide thin films synthesized by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Patil, P. S.; Kawar, R. K.; Sadale, S. B.; Inamdar, A. I.; Deshmukh, H. P.

    2006-09-01

    Molybdenum-doped iridium oxide thin films have been deposited onto corning glass- and fluorine-doped tin oxide coated corning glass substrates at 350 °C by using a pneumatic spray pyrolysis technique. An aqueous solution of 0.01 M ammonium molybdate was mixed with 0.01 M iridium trichloride solution in different volume proportions and the resultant solution was used as a precursor solution for spraying. The as-deposited samples were annealed at 600 °C in air medium for 1 h. The structural, electrical and optical properties of as-deposited and annealed Mo-doped iridium oxide were studied and values of room temperature electrical resistivity, and thermoelectric power were estimated. The as-deposited samples with 2% Mo doping exhibit more pronounced electrochromism than other samples, including pristine Ir oxide.

  1. Uniform nanoparticles by flame-assisted spray pyrolysis (FASP) of low cost precursors.

    PubMed

    Rudin, Thomas; Wegner, Karsten; Pratsinis, Sotiris E

    2011-07-01

    A new flame-assisted spray pyrolysis (FASP) reactor design is presented, which allows the use of inexpensive precursors and solvents (e.g., ethanol) for synthesis of nanoparticles (10-20 nm) with uniform characteristics. In this reactor design, a gas-assisted atomizer generates the precursor solution spray that is mixed and combusted with externally fed inexpensive fuel gases (acetylene or methane) at a defined height above the atomizing nozzle. The gaseous fuel feed can be varied to control the combustion enthalpy content of the flame and onset of particle formation. This way, the enthalpy density of the flame is decoupled from the precursor solution composition. Low enthalpy content precursor solutions are prone to synthesis of non-uniform particles (e.g., bimodal particle size distribution) by standard flame spray pyrolysis (FSP) processes. For example, metal nitrates in ethanol typically produce nanosized particles by gas-to-particle conversion along with larger particles by droplet-to-particle conversion. The present FASP design facilitates the use of such low enthalpy precursor solutions for synthesis of homogeneous nanopowders by increasing the combustion enthalpy density of the flame with low-cost, gaseous fuels. The effect of flame enthalpy density on product properties in the FASP configuration is explored by the example of Bi(2)O(3) nanoparticles produced from bismuth nitrate in ethanol. Product powders were characterized by nitrogen adsorption, X-ray diffraction, X-ray disk centrifuge, and transmission electron microscopy. Homogeneous Bi(2)O(3) nanopowders were produced both by increasing the gaseous fuel content and, most notably, by cutting the air entrainment prior to ignition of the spray.

  2. Uniform nanoparticles by flame-assisted spray pyrolysis (FASP) of low cost precursors

    PubMed Central

    Rudin, Thomas; Wegner, Karsten

    2013-01-01

    A new flame-assisted spray pyrolysis (FASP) reactor design is presented, which allows the use of inexpensive precursors and solvents (e.g., ethanol) for synthesis of nanoparticles (10–20 nm) with uniform characteristics. In this reactor design, a gas-assisted atomizer generates the precursor solution spray that is mixed and combusted with externally fed inexpensive fuel gases (acetylene or methane) at a defined height above the atomizing nozzle. The gaseous fuel feed can be varied to control the combustion enthalpy content of the flame and onset of particle formation. This way, the enthalpy density of the flame is decoupled from the precursor solution composition. Low enthalpy content precursor solutions are prone to synthesis of non-uniform particles (e.g., bimodal particle size distribution) by standard flame spray pyrolysis (FSP) processes. For example, metal nitrates in ethanol typically produce nanosized particles by gas-to-particle conversion along with larger particles by droplet-to-particle conversion. The present FASP design facilitates the use of such low enthalpy precursor solutions for synthesis of homogeneous nanopowders by increasing the combustion enthalpy density of the flame with low-cost, gaseous fuels. The effect of flame enthalpy density on product properties in the FASP configuration is explored by the example of Bi2O3 nanoparticles produced from bismuth nitrate in ethanol. Product powders were characterized by nitrogen adsorption, X-ray diffraction, X-ray disk centrifuge, and transmission electron microscopy. Homogeneous Bi2O3 nanopowders were produced both by increasing the gaseous fuel content and, most notably, by cutting the air entrainment prior to ignition of the spray. PMID:23408113

  3. Uniform nanoparticles by flame-assisted spray pyrolysis (FASP) of low cost precursors

    NASA Astrophysics Data System (ADS)

    Rudin, Thomas; Wegner, Karsten; Pratsinis, Sotiris E.

    2011-07-01

    A new flame-assisted spray pyrolysis (FASP) reactor design is presented, which allows the use of inexpensive precursors and solvents (e.g., ethanol) for synthesis of nanoparticles (10-20 nm) with uniform characteristics. In this reactor design, a gas-assisted atomizer generates the precursor solution spray that is mixed and combusted with externally fed inexpensive fuel gases (acetylene or methane) at a defined height above the atomizing nozzle. The gaseous fuel feed can be varied to control the combustion enthalpy content of the flame and onset of particle formation. This way, the enthalpy density of the flame is decoupled from the precursor solution composition. Low enthalpy content precursor solutions are prone to synthesis of non-uniform particles (e.g., bimodal particle size distribution) by standard flame spray pyrolysis (FSP) processes. For example, metal nitrates in ethanol typically produce nanosized particles by gas-to-particle conversion along with larger particles by droplet-to-particle conversion. The present FASP design facilitates the use of such low enthalpy precursor solutions for synthesis of homogeneous nanopowders by increasing the combustion enthalpy density of the flame with low-cost, gaseous fuels. The effect of flame enthalpy density on product properties in the FASP configuration is explored by the example of Bi2O3 nanoparticles produced from bismuth nitrate in ethanol. Product powders were characterized by nitrogen adsorption, X-ray diffraction, X-ray disk centrifuge, and transmission electron microscopy. Homogeneous Bi2O3 nanopowders were produced both by increasing the gaseous fuel content and, most notably, by cutting the air entrainment prior to ignition of the spray.

  4. Study of optical and structural properties of CZTS thin films grown by co-evaporation and spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Moreno, R.; Ramirez, E. A.; Gordillo Guzmán, G.

    2016-02-01

    Results regarding optical and structural properties of Cu2ZnSnS4 (CZTS) thin films prepared by co-evaporation using a novel procedure are compared with those obtained with CZTS films grown using a solution based route. The lattice strain ε and crystallite size D of CZTS films prepared by co-evaporation and by spray pyrolysis were estimated through X-ray diffraction (XRD) measurements using Williamson-Hall-isotropic strain model. The results of estimated average crystallite size of CZTS films by Scherrer and Williamson-Hall plot methods were compared with AFM (atomic force microscopy) measurements. It was found that the average crystallite size measured by Williamson-Hall plot methods agree quite well with AFM results. Further, information regarding the influence of preparation method on both, crystalline phases and the formation of structural defects was achieved through Raman and Urbach energy measurements.

  5. Antimony-Doped Tin Oxide Thin Films Grown by Home Made Spray Pyrolysis Technique

    NASA Astrophysics Data System (ADS)

    Yusuf, Gbadebo; Babatola, Babatunde Keji; Ishola, Abdulahi Dimeji; Awodugba, Ayodeji O.; Solar cell Collaboration

    2016-03-01

    Transparent conducting antimony-doped tin oxide (ATO) films have been deposited on glass substrates by home made spray pyrolysis technique. The structural, electrical and optical properties of the ATO films have been investigated as a function of Sb-doping level and annealing temperature. The optimum target composition for high conductivity and low resistivity was found to be 20 wt. % SnSb2 + 90 wt. ATO. Under optimized deposition conditions of 450oC annealing temperature, electrical resistivity of 5.2×10-4 Ω -cm, sheet resistance of 16.4 Ω/sq, average optical transmittance of 86% in the visible range, and average optical band-gap of 3.34eV were obtained. The film deposited at lower annealing temperature shows a relatively rough, loosely bound slightly porous surface morphology while the film deposited at higher annealing temperature shows uniformly distributed grains of greater size. Keywords: Annealing, Doping, Homemade spray pyrolysis, Tin oxide, Resistivity

  6. Analysis of carrier gas flow rate effect on hydroxyapatite particle formation in ultrasonic spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Widiyastuti, W.; Setiawan, Adhi; Nurtono, Tantular; Winardi, Sugeng

    2016-02-01

    Ultrasonic spray pyrolysis has been well-known process for producing fine particles from single and multicomponent materials. Here, the effect of carrier gas flow rate in ultrasonic spray pyrolysis process was studied in the particle formation of hydroxyapatite using solution precursor of Ca(CH3COO)2 and (NH4)2HPO4 with Ca/P ratio of 1.67. The experimental analysis was accompanied with computational fluid dynamics (CFD) simulation for comparison. In the simulation, the evaporation of the solvent in the droplets, a second evaporation due to crust formation, the decomposition reaction of the precursor involving the transfer of heat and mass transfer from droplet to surrounding were considered. By maintaining temperature at 900 °C, the residence time increased with decreasing the carrier gas flow rate led to the increasing the evaporation rate and the reacted fraction of the precursor. The predicted and experimental results of average particles size were agreed well with discrepancy 6.3%.

  7. Electrochemical properties of tungsten sulfide–carbon composite microspheres prepared by spray pyrolysis

    PubMed Central

    Choi, Seung Ho; Boo, Sung Jin; Lee, Jong-Heun; Kang, Yun Chan

    2014-01-01

    Tungsten sulfide (WS2)–carbon composite powders with superior electrochemical properties are prepared by a two-step process. WO3-carbon composite powders were first prepared by conventional spray pyrolysis, and they were then sulfidated to form WS2-carbon powders. Bare WS2 powders are also prepared by sulfidation of bare WO3 powders obtained by spray pyrolysis. Stacked graphitic layers could not be found in the bare WS2 and WS2–carbon composite powders. The amorphous bare WS2 and WS2–carbon composite powders have Brunauer–Emmett–Teller (BET) surface areas of 2.8 and 4 m2 g−1, respectively. The initial discharge and charge capacities of the WS2–carbon composite powders at a current density of 100 mA g−1 are 1055 and 714 mA h g−1, respectively, and the corresponding initial Coulombic efficiency is 68%. On the other hand, the initial discharge and charge capacities of the bare WS2 powders are 514 and 346 mA h g−1, respectively. The discharge capacities of the WS2–carbon composite powders for the 2nd and 50th cycles are 716 and 555 mA h g−1, respectively, and the corresponding capacity retention measured after first cycle is 78%. PMID:25169439

  8. Fabrication of solid oxide fuel cell anode electrode by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Liu, Lin; Kim, Gap-Yong; Chandra, Abhijit

    Large triple phase boundaries (TPBs) and high gas diffusion capability are critical in enhancing the performance of a solid oxide fuel cell (SOFC). In this study, ultrasonic spray pyrolysis has been investigated to assess its capability in controlling the anode microstructure. Deposition of porous anode film of nickel and Ce 0.9Gd 0.1O 1.95 on a dense 8 mol.% yttria stabilized zirconia (YSZ) substrate was carried out. First, an ultrasonic atomization model was utilized to predict the deposited particle size. The model accurately estimated the deposited particle size based on the feed solution condition. Second, effects of various process parameters, which included the precursor solution feed rate, precursor solution concentration and deposition temperature, on the TPB formation and porosity were investigated. The deposition temperature and precursor solution concentration were the most critical parameters that influenced the morphology, porosity and particle size of the anode electrode. Ultrasonic spray pyrolysis achieved homogeneous distribution of constitutive elements within the deposited particles and demonstrated capability to control the particle size and porosity in the range of 2-17 μm and 21-52%, respectively.

  9. Boron doped nanostructure ZnO films deposited by ultrasonic spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Karakaya, Seniye; Ozbas, Omer

    2015-02-01

    ZnO is an II-VI compound semiconductor with a wide direct band gap of 3.3 eV at room temperature. Doped with group III elements (B, Al or Ga), it becomes an attractive candidate to replace tin oxide (SnO2) or indium tin oxide (ITO) as transparent conducting electrodes in solar cell devices and flat panel display due to competitive electrical and optical properties. In this work, ZnO and boron doped ZnO (ZnO:B) films have been deposited onto glass substrates at 350 ± 5 °C by a cost-efficient ultrasonic spray pyrolysis technique. The optical, structural, morphological and electrical properties of nanostructure undoped and ZnO:B films have been investigated. Electrical resistivity of films has been analyzed by four-probe technique. Optical properties and thicknesses of the films have been examined in the wavelength range 1200-1600 nm by using spectroscopic ellipsometry (SE) measurements. The optical constants (refractive index (n) and extinction coefficient (k)) and the thicknesses of the films have been fitted according to Cauchy model. The optical method has been used to determine the band gap value of the films. Transmission spectra have been taken by UV spectrophotometer. It is found that both ZnO and ZnO:B films have high average optical transmission (≥80%). X-ray diffraction (XRD) patterns indicate that the obtained ZnO has a hexagonal wurtzite type structure. The morphological properties of the films were studied by atomic force microscopy (AFM). The surface morphology of the nanostructure films is found to depend on the concentration of B. As a result, ZnO:B films are promising contender for their potential use as transparent window layer and electrodes in solar cells.

  10. Low-cost plasmonic solar cells prepared by chemical spray pyrolysis

    PubMed Central

    Katerski, Atanas; Oja Acik, Ilona; Mikli, Valdek; Mere, Arvo; Sildos, Ilmo; Krunks, Malle

    2014-01-01

    Summary Solar cells consisting of an extremely thin In2S3/CuInS2 buffer/absorber layer uniformly covering planar ZnO were prepared entirely by chemical spray pyrolysis. Au nanoparticles (Au-NPs) were formed via thermal decomposition of a gold(III) chloride trihydrate (HAuCl4·3H2O) precursor by spraying 2 mmol/L of the aqueous precursor solution onto a substrate held at 260 °C. Current–voltage scans and external quantum efficiency spectra were used to evaluate the solar cell performance. This work investigates the effect of the location of the Au-NP layer deposition (front side vs rear side) in the solar cell and the effect of varying the volume (2.5–10 mL) of the sprayed Au precursor solution. A 63% increase (from 4.6 to 7.5 mA/cm2) of the short-circuit current density was observed when 2.5 mL of the precursor solution was deposited onto the rear side of the solar cell. PMID:25551068

  11. Low-cost plasmonic solar cells prepared by chemical spray pyrolysis.

    PubMed

    Kärber, Erki; Katerski, Atanas; Oja Acik, Ilona; Mikli, Valdek; Mere, Arvo; Sildos, Ilmo; Krunks, Malle

    2014-01-01

    Solar cells consisting of an extremely thin In2S3/CuInS2 buffer/absorber layer uniformly covering planar ZnO were prepared entirely by chemical spray pyrolysis. Au nanoparticles (Au-NPs) were formed via thermal decomposition of a gold(III) chloride trihydrate (HAuCl4·3H2O) precursor by spraying 2 mmol/L of the aqueous precursor solution onto a substrate held at 260 °C. Current-voltage scans and external quantum efficiency spectra were used to evaluate the solar cell performance. This work investigates the effect of the location of the Au-NP layer deposition (front side vs rear side) in the solar cell and the effect of varying the volume (2.5-10 mL) of the sprayed Au precursor solution. A 63% increase (from 4.6 to 7.5 mA/cm(2)) of the short-circuit current density was observed when 2.5 mL of the precursor solution was deposited onto the rear side of the solar cell.

  12. Characterization and Electrochromic Properties of Vanadium Oxide Thin Films Prepared via Spray Pyrolysis

    NASA Astrophysics Data System (ADS)

    Mousavi, M.; Kompany, A.; Shahtahmasebi, N.; Bagheri-Mohagheghi, M.-M.

    2013-08-01

    Vanadium oxide thin films were grown on glass substrates using spray pyrolysis technique. The effects of substrate temperature, vanadium concentration in the initial solution and the solution spray rate on the nanostructural and the electrochromic properties of deposited films are investigated. Characterization and the electrochromic measurements were carried out using X-ray diffraction, scanning electron microscopy and cyclic voltammogram. XRD patterns showed that the prepared films have polycrystalline structure and are mostly mixed phases of orthorhombic α-V2O5 along with minor β-V2O5 and V4O9 tetragonal structures. The preferred orientation of the deposited films was found to be along [101] plane. The cyclic voltammogram results obtained for different samples showed that only the films with 0.2 M solution concentration, 5 ml/min solution spray rate and 450°C substrate temperature exhibit two-step electrochromic properties. The results show a correlation between cycle voltammogram, morphology and resistance of the films.

  13. Formation of CuAlO2 Film by Ultrasonic Spray Pyrolysis

    NASA Astrophysics Data System (ADS)

    Iping, S.; Lockman, Zainovia; Hutagalung, S. D.; Kamsul, A.; Matsuda, Atsunori

    2011-10-01

    Smooth, crack free and homogenous CuAlO2 film was produced by chemical solution deposition process via spray pyrolysis technique on a cleaned Si substrate. The precursor solution used was comprised of a mixture of 45.87 mmol Cu(NO3)2.3H2O and 90 mmol Al(NO3)3.9H2O at ratio of Cu:Al = 1.2:1. The precursor solution was placed in a mist chamber and was atomized by a nebulizer to produce precursor mist. The precursor mist was then carried out by Ar gas and was sprayed onto a heated Si. Two main parameters were studied: the distance between the nozzle of the precursor mist chamber and the Si and the temperature of the Si substrate. It appears that from the XRD data, CuAlO2 can be detected for samples prepared by spraying the precursor mist at temperature of > 550 °C with distance between the nozzle and the substrate of 3cm. Reaction of the Cu and Al ions in the mist near the substrate may have promoted the crystallisation of CuAlO2.

  14. Properties of NiO thin films deposited by intermittent spray pyrolysis process

    NASA Astrophysics Data System (ADS)

    Reguig, B. A.; Khelil, A.; Cattin, L.; Morsli, M.; Bernède, J. C.

    2007-02-01

    NiO thin films have been grown on glass substrates by intermittent spray pyrolysis deposition of NiCl 2·6H 2O diluted in distilled water, using a simple "perfume atomizer". The effect of the solution molarity on their properties was studied and compared to those of NiO thin films deposited with a classical spray system. It is shown that NiO thin films crystallized in the NiO structure are achieved after deposition. Whatever the precursor molarity, the grain size is around 25-30 nm. The crystallites are preferentially oriented along the (1 1 1) direction. All the films are p-type. However, the thickness and the conductivity of the NiO films depend on the precursor contraction. By comparison with the properties of films deposited by classical spray technique, it is shown that the critical precursor concentration, which induces strong thin films properties perturbations, is higher when a perfume atomizer is used. This broader stability domain can be attributed to better chlorides decomposition during the rest time used in the perfume atomizer technique.

  15. Methods for deoxygenating biomass-derived pyrolysis oil

    DOEpatents

    Brandvold, Timothy A.

    2015-07-14

    Methods for deoxygenating a biomass-derived pyrolysis oil are provided. A method comprising the steps of diluting the biomass-derived pyrolysis oil with a phenolic-containing diluent to form a diluted pyoil-phenolic feed is provided. The diluted pyoil-phenolic feed is contacted with a deoxygenating catalyst in the presence of hydrogen at hydroprocessing conditions effective to form a low-oxygen biomass-derived pyrolysis oil effluent.

  16. Polymetallic citric complexes as precursors for spray-pyrolysis deposition of thin ferrite films

    NASA Astrophysics Data System (ADS)

    Milanova, M.; Koleva, I.; Todorovska, R.; Zaharieva, J.; Кostadinov, M.; Todorovsky, D.

    2011-06-01

    Thin films of ferrites of the type M IIFe 2O 4 (M = Cu, Mg, Zn) are prepared by spray-pyrolysis using ethylene glycol solutions of mixed-metal citric complexes of the respective metals at substrate temperature between 350 °C and 450 °C and post-deposition annealing at 480-750 °C in air. Phase composition, crystal structure, morphology and adhesion of the obtained films (40-400 nm in thickness) are studied by X-ray diffraction, SEM, energy dispersive X-ray microanalysis and AFM. Single phase dense uniform films with grains from 30-100 nm (M = Cu, Mg) to 0.15-2 μm (M = Zn) are obtained.

  17. Ultra-low thermal conductivity of nanogranular indium tin oxide films deposited by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Brinzari, Vladimir I.; Cocemasov, Alexandr I.; Nika, Denis L.; Korotcenkov, Ghenadii S.

    2017-02-01

    The authors have shown that nanogranular indium tin oxide (ITO) films, deposited by spray pyrolysis on a silicon substrate, demonstrate ultralow thermal conductivity κ ˜ 0.84 ± 0.12 Wm-1 K-1 at room temperature. This value is approximately by one order of magnitude lower than that in bulk ITO. The strong drop of thermal conductivity is explained by the nanogranular structure and porosity of ITO films, resulting in enhanced phonon scattering on grain boundaries. The experimental results were interpreted theoretically, employing the Boltzmann transport equation approach for phonon transport and filtering model for electronic transport. The calculated values of thermal conductivity are in reasonable agreement with the experimental findings. The presented results show that ITO films with an optimal nanogranular structure may be prospective for thermoelectric applications.

  18. Structural, optical, electrical and thermal properties of zinc oxide thin films by chemical spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Shinde, S. S.; Bhosale, C. H.; Rajpure, K. Y.

    2012-08-01

    Thin films of highly textured ZnO are synthesized by simple chemical spray pyrolysis onto corning glass substrates in aqueous medium. The influence of solution concentration onto photoelectrochemical, structural, morphological, compositional, optical, electrical and thermal properties have been investigated. Structural analysis shows the hexagonal (wurtzite) crystal structure. Electron-phonon-coupling in ZnO films has analyzed using Raman spectroscopy. The chemical composition and valence states of constituent elements in ZnO are analyzed by X-ray photoelectron spectroscopy. The SEM and AFM micrographs depict the films are compact and homogeneous (hexagonal platelets nanostructures) with varying grain sizes (average grain size ˜50-150 nm). The specific heat and thermal conductivity study shows the phonon conduction behavior is dominant in these polycrystalline films.

  19. Synthesis of ZnO Microrods by the Spray Pyrolysis Technique

    NASA Astrophysics Data System (ADS)

    Ikhmayies, Shadia J.

    2016-08-01

    Zinc oxide (ZnO) microrods were synthesized by the spray pyrolysis technique on aluminum substrates at a substrate temperature of 350 ± 5°C. The samples were characterized by x-ray diffraction (XRD), x-ray fluorescence (XRF), scanning electron microscopy (SEM), and energy dispersion x-ray spectroscopy (EDX). XRD diffractograms presented the wurtzite (hexagonal) structure with (002) as the preferential orientation. The SEM observations showed typical microrods of hexagonal cross sections with lengths in the range 1.0-2.5 μm and diameter in the range 300-400 nm. XRF and EDX analysis revealed that the samples contain chlorine, and other impurities, which are related to the aluminum substrate and the starting material zinc chloride (ZnCl2). It is found that the microrods are rich in oxygen, which make them of potential use in gas sensors, besides solar cells, lithium ion batteries and other electo-optic devices.

  20. Improvement on droplet production rate of ultrasonic - nebulizer in spray pyrolysis process

    NASA Astrophysics Data System (ADS)

    Panatarani, Camellia; Demen, Tuti Aryati; Men, Liu Kin; Maulana, Dwindra Wilham; Hidayat, Darmawan; Joni, I. Made

    2013-09-01

    Atomization is an important part in Spray Pyrolysis (SP) process which is applied to synthesize submicron or nano sized particles or to deposit thin film. Ultrasonic Nebulizer (UN) is usually use in SP due to its homogeneous droplets production with size between 1-5 μm. The drawback of the UN is low droplets production rate. In this research, we successfully developed a Digital Ultrasonic Nebulizer (DUN) with high droplets production rate using two ultrasonic traducers with applied frequency of 2.4 MHz. The result of DUN atomization was improved 4-6 fold compare to the conventional UN. The DUN also has an additional digital features such as pushbutton, LCD and microcontroller which is allow to set duration and applied voltage.

  1. Synthesis of Single Crystalline ZnO Nanoparticles by Salt-Assisted Spray Pyrolysis

    NASA Astrophysics Data System (ADS)

    Panatarani, Camellia; Lenggoro, I. Wuled; Okuyama, Kikuo

    2003-04-01

    LiNO3 was used as a shield in the preparation of single crystalline ZnO particles by a spray pyrolysis process in order to prevent agglomeration and enhance the crystallinity of the ZnO. LiNO3 was added to a precursor solution of zinc acetate dihydrate prior to its atomization by means of an ultrasonic transducer. Agglomerate-free particles having a mean particle size of 26 nm were successfully obtained after washing the product. X-ray diffractometry, field-emission scanning electron micrograph and transmission electron micrograph data indicate that the size and morphology of ZnO were strongly influenced by the operating temperature used and the residence time of the particle in the reactor.

  2. The piezoelectric effect on zinc oxide nano on polyimide substrate by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Idris, A. A. M.; Arsat, R.; Ahmad, M. K.

    2017-03-01

    This paper reports the effect of the deposition conditions crystal quality and film thickness of the Zinc Oxide (ZnO) film on the polyimide substrate. The ZnO film has been deposited by using the spray pyrolysis technique. This technique needs Zinc Nitrate Hexahydrate with the mixture of deionized water. At 350 °C, a higher c-axis preferred orientation at peak 0002 crystal orientation, which is critical for piezoelectric applications in ZnO thin films are obtained with the thickness of thin film is 300ηm. It also produces the 204.8 Hz of frequency which is higher than other frequency obtained by lower growth temperature.

  3. Synthesis of MgO powder from magnesium nitrate using spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Pradita, T.; Shih, S. J.; Aji, B. B.; Sudibyo

    2017-03-01

    A variety of advantages such as catalyst, paints, flame retardants, semiconductors, additives in refractory and solid adsorbent can be obtained from Magnesium Oxide (MgO) based material. Ultrasonic spray pyrolysis (SP) process was conducted to synthesize MgO from Mg(NO3)2.6H2O (MgN) precursor. The MgO particles were characterized using Thermogravimetric Analysis (TGA), X-Ray Diffraction analysis (XRD) and Field Emission-Secondary Electron Microscopy (FE-SEM). In this study, Hollow spherical and irregular MgO particles were successfully obtained. It suggests that the particle size will decrease along with the increasing of the SP temperature, the smallest particle size obtained is in the range of 354±104 nm at 900°C SP temperature.

  4. Solution-based carbohydrate synthesis of individual solid, hollow, and porous carbon nanospheres using spray pyrolysis.

    PubMed

    Wang, Chengwei; Wang, Yuan; Graser, Jake; Zhao, Ran; Gao, Fei; O'Connell, Michael J

    2013-12-23

    A facile and scalable solution-based, spray pyrolysis synthesis technique was used to synthesize individual carbon nanospheres with specific surface area (SSA) up to 1106 m(2)/g using a novel metal-salt catalyzed reaction. The carbon nanosphere diameters were tunable from 10 nm to several micrometers by varying the precursor concentrations. Solid, hollow, and porous carbon nanospheres were achieved by simply varying the ratio of catalyst and carbon source without using any templates. These hollow carbon nanospheres showed adsorption of to 300 mg of dye per gram of carbon, which is more than 15 times higher than that observed for conventional carbon black particles. When evaluated as supercapacitor electrode materials, specific capacitances of up to 112 F/g at a current density of 0.1 A/g were observed, with no capacitance loss after 20,000 cycles.

  5. Properties of antimony doped ZnO thin films deposited by spray pyrolysis technique

    SciTech Connect

    Sadananda Kumar, N. Bangera, Kasturi V.; Shivakumar, G. K.

    2015-07-15

    Antimony (Sb) doped zinc oxide (ZnO) thin films were deposited on the glass substrate at 450°C using spray pyrolysis technique. Effect of Sb doping on surface morphology structural, optical and electrical properties were studied. X-ray diffraction (XRD) analysis showed that both the undoped and doped ZnO thin films are polycrystalline in nature with (101) preferred orientation. SEM analysis showed a change in surface morphology of Sb doped ZnO thin films. Doping results in a marked increase in conductivity without affecting the transmittance of the films. ZnO films prepared with 3 at % Sb shows the lowest resistivity of 0.185 Ohm cm with a Hall mobility of 54.05 cm{sup 2} V{sup –1} s{sup –1}, and a hole concentration of 6.25 × 10{sup 17} cm{sup –3}.

  6. Enhanced early osteogenic differentiation by silicon-substituted hydroxyapatite ceramics fabricated via ultrasonic spray pyrolysis route.

    PubMed

    Honda, Michiyo; Kikushima, Koichi; Kawanobe, Yusuke; Konishi, Toshiisa; Mizumoto, Minori; Aizawa, Mamoru

    2012-12-01

    The influence of silicon-substituted hydroxyapatite (Si-HAp) on osteogenic differentiation was assessed by biological analysis. Si-HAp was prepared by ultrasonic spray pyrolysis (USSP) technique using various amounts of Si (0, 0.8, and 1.6 mass%). Chemical analysis revealed that Si was incorporated into the hydroxyapatite (HAp) lattice with no other crystalline phase and which caused the change of crystal structure. Biological analyses showed that the Si contents affected the cell proliferation and morphology, suggesting that there is an optimal Si content for cell culture. As for differentiation, alkaline phosphatase activity and osteocalcin production of Si-HAp were higher than those of HAp. Gene expression profiles also revealed that substitution of Si (0.8 mass%) up-regulated the expression levels of osteocalcin and especially Runx2, a master gene for osteoblast development. These results suggest that incorporating Si into the HAp lattice may enhance the bioactivity, particularly during early osteoblast development.

  7. Sb2S3 grown by ultrasonic spray pyrolysis and its application in a hybrid solar cell

    PubMed Central

    Katerski, Atanas; Oja Acik, Ilona; Mere, Arvo; Mikli, Valdek; Krunks, Malle

    2016-01-01

    Chemical spray pyrolysis (CSP) is a fast wet-chemical deposition method in which an aerosol is guided by carrier gas onto a hot substrate where the decomposition of the precursor chemicals occurs. The aerosol is produced using an ultrasonic oscillator in a bath of precursor solution and guided by compressed air. The use of the ultrasonic CSP resulted in the growth of homogeneous and well-adhered layers that consist of submicron crystals of single-phase Sb2S3 with a bandgap of 1.6 eV if an abundance of sulfur source is present in the precursor solution (SbCl3/SC(NH2)2 = 1:6) sprayed onto the substrate at 250 °C in air. Solar cells with glass-ITO-TiO2-Sb2S3-P3HT-Au structure and an active area of 1 cm2 had an open circuit voltage of 630 mV, short circuit current density of 5 mA/cm2, a fill factor of 42% and a conversion efficiency of 1.3%. Conversion efficiencies up to 1.9% were obtained from solar cells with smaller areas. PMID:28144515

  8. Sb2S3 grown by ultrasonic spray pyrolysis and its application in a hybrid solar cell.

    PubMed

    Kärber, Erki; Katerski, Atanas; Oja Acik, Ilona; Mere, Arvo; Mikli, Valdek; Krunks, Malle

    2016-01-01

    Chemical spray pyrolysis (CSP) is a fast wet-chemical deposition method in which an aerosol is guided by carrier gas onto a hot substrate where the decomposition of the precursor chemicals occurs. The aerosol is produced using an ultrasonic oscillator in a bath of precursor solution and guided by compressed air. The use of the ultrasonic CSP resulted in the growth of homogeneous and well-adhered layers that consist of submicron crystals of single-phase Sb2S3 with a bandgap of 1.6 eV if an abundance of sulfur source is present in the precursor solution (SbCl3/SC(NH2)2 = 1:6) sprayed onto the substrate at 250 °C in air. Solar cells with glass-ITO-TiO2-Sb2S3-P3HT-Au structure and an active area of 1 cm(2) had an open circuit voltage of 630 mV, short circuit current density of 5 mA/cm(2), a fill factor of 42% and a conversion efficiency of 1.3%. Conversion efficiencies up to 1.9% were obtained from solar cells with smaller areas.

  9. Methods for deoxygenating biomass-derived pyrolysis oil

    DOEpatents

    Baird, Lance Awender; Brandvold, Timothy A.

    2015-06-30

    Methods for deoxygenating a biomass-derived pyrolysis oil are provided. A method for deoxygenating a biomass-derived pyrolysis oil comprising the steps of combining a biomass-derived pyrolysis oil stream with a heated low-oxygen-pyoil diluent recycle stream to form a heated diluted pyoil feed stream is provided. The heated diluted pyoil feed stream has a feed temperature of about 150.degree. C. or greater. The heated diluted pyoil feed stream is contacted with a first deoxygenating catalyst in the presence of hydrogen at first hydroprocessing conditions effective to form a low-oxygen biomass-derived pyrolysis oil effluent.

  10. Method and apparatus for producing pyrolysis oil having improved stability

    SciTech Connect

    Baird, Lance A.; Brandvold, Timothy A.; Muller, Stefan

    2016-12-27

    Methods and apparatus to improve hot gas filtration to reduce the liquid fuel loss caused by prolonged residence time at high temperatures are described. The improvement can be obtained by reducing the residence time at elevated temperature by reducing the temperature of the pyrolysis vapor, by reducing the volume of the pyrolysis vapor at the elevated temperature, by increasing the volumetric flow rate at constant volume of the pyrolysis vapor, or by doing a combination of these.

  11. Chemical spray pyrolysis of β-In2S3 thin films deposited at different temperatures

    NASA Astrophysics Data System (ADS)

    Sall, Thierno; Marí Soucase, Bernabé; Mollar, Miguel; Hartitti, Bouchaib; Fahoume, Mounir

    2015-01-01

    In2S3 thin films were deposited onto indium tin oxide-coated glass substrates by chemical spray pyrolysis while keeping the substrates at different temperatures. The structures of the sprayed In2S3 thin films were characterized by X-ray diffraction (XFD). The quality of the thin films was determined by Raman spectroscopy. Scanning electron microscopy (SEM) and atomic force microscopy were used to explore the surface morphology and topography of the thin films, respectively. The optical band gap was determined based on optical transmission measurements. The indium sulfide phase exhibited a preferential orientation in the (0, 0, 12) crystallographic direction according to the XRD analysis. The phonon vibration modes determined by Raman spectroscopy also confirmed the presence of the In2S3 phase in our samples. According to SEM, the surface morphologies of the films were free of defects. The optical band gap energy varied from 2.82 eV to 2.95 eV.

  12. Flame spray pyrolysis: An enabling technology for nanoparticles design and fabrication

    NASA Astrophysics Data System (ADS)

    Teoh, Wey Yang; Amal, Rose; Mädler, Lutz

    2010-08-01

    Combustion of appropriate precursor sprays in a flame spray pyrolysis (FSP) process is a highly promising and versatile technique for the rapid and scalable synthesis of nanostuctural materials with engineered functionalities. The technique was initially derived from the fundamentals of the well-established vapour-fed flame aerosols reactors that was widely practised for the manufacturing of simple commodity powders such as pigmentary titania, fumed silica, alumina, and even optical fibers. In the last 10 years however, FSP knowledge and technology was developed substantially and a wide range of new and complex products have been synthesised, attracting major industries in a diverse field of applications. Key innovations in FSP reactor engineering and precursor chemistry have enabled flexible designs of nanostructured loosely-agglomerated powders and particulate films of pure or mixed oxides and even pure metals and alloys. Unique material morphologies such as core-shell structures and nanorods are possible using this essentially one step and continuous FSP process. Finally, research challenges are discussed and an outlook on the next generation of engineered combustion-made materials is given.

  13. Pyrolysis and catalytic pyrolysis as a recycling method of waste CDs originating from polycarbonate and HIPS

    SciTech Connect

    Antonakou, E.V.; Kalogiannis, K.G.; Stephanidis, S.D.; Triantafyllidis, K.S.; Lappas, A.A.; Achilias, D.S.

    2014-12-15

    Highlights: • Thermal and catalytic pyrolysis is a powerful method for recycling of WEEEs. • Liquid products obtained from the pyrolysis of PC or HIPS found in waste CDs are very different. • Mainly phenols are obtained from pyrolysis PC based wastes while aromatics from HIPS. • Use of MgO catalyst increases the amount of phenols from CD recycling compared to ZSM-5. • Use of MgO or ZSM-5 catalysts reduces the amount of styrene recovered from HIPS. - Abstract: Pyrolysis appears to be a promising recycling process since it could convert the disposed polymers to hydrocarbon based fuels or various useful chemicals. In the current study, two model polymers found in WEEEs, namely polycarbonate (PC) and high impact polystyrene (HIPS) and their counterparts found in waste commercial Compact Discs (CDs) were pyrolysed in a bench scale reactor. Both, thermal pyrolysis and pyrolysis in the presence of two catalytic materials (basic MgO and acidic ZSM-5 zeolite) was performed for all four types of polymers. Results have shown significant recovery of the monomers and valuable chemicals (phenols in the case of PC and aromatic hydrocarbons in the case of HIPS), while catalysts seem to decrease the selectivity towards the monomers and enhance the selectivity towards other desirable compounds.

  14. Effect of solvent composition on oxide morphology during flame spray pyrolysis of metal nitrates.

    PubMed

    Strobel, Reto; Pratsinis, Sotiris E

    2011-05-28

    The effect of solvent composition on particle formation during flame spray pyrolysis of inexpensive metal-nitrates has been investigated for alumina, iron oxide, cobalt oxide, zinc oxide and magnesium oxide. The as-prepared materials were characterized by electron microscopy, nitrogen adsorption, X-ray diffraction (XRD) and disc centrifugation (XDC). The influence of solvent parameters such as boiling point, combustion enthalpy and chemical reactivity on formation of either homogeneous nanoparticles by evaporation/nucleation/coagulation (gas-to-particle conversion) or large particles through precipitation and conversion within the sprayed droplets (droplet-to-particle conversion) is discussed. For Al(2)O(3), Fe(2)O(3), Co(3)O(4) and partly also MgO, the presence of a carboxylic acid in the FSP solution resulted in homogeneous nanoparticles. This is attributed to formation of volatile metal carboxylates in solution as evidenced by attenuated total reflectance spectroscopy (ATR). For ZnO and MgO rather homogeneous nanoparticles were formed regardless of solvent composition. For ZnO this is attributed to its relatively low dissociation temperature compared to other oxides. While for MgO this is traced to the high decomposition temperature of Mg(NO(3))(2) together with Mg(OH)(2)↔MgO transformations. Cobalt oxide (Co(3)O(4)) nanoparticles made by FSP were not aggregated but rather loosely agglomerated as determined by the excellent agreement between XRD- and XDC-derived crystallite and particle sizes, respectively, pointing out the potential of FSP to make non-aggregated particles.

  15. Properties of NiO thin films deposited by chemical spray pyrolysis using different precursor solutions

    NASA Astrophysics Data System (ADS)

    Cattin, L.; Reguig, B. A.; Khelil, A.; Morsli, M.; Benchouk, K.; Bernède, J. C.

    2008-07-01

    NiO thin films have been deposited by chemical spray pyrolysis using a perfume atomizer to grow the aerosol. The influence of the precursor, nickel chloride hexahydrate (NiCl 2·6H 2O), nickel nitrate hexahydrate (Ni(NO 3) 2·6H 2O), nickel hydroxide hexahydrate (Ni(OH) 2·6H 2O), nickel sulfate tetrahydrate (NiSO 4·4H 2O), on the thin films properties has been studied. In the experimental conditions used (substrate temperature 350 °C, precursor concentration 0.2-0.3 M, etc.), pure NiO thin films crystallized in the cubic phase can be achieved only with NiCl 2 and Ni(NO 3) 2 precursors. These films have been post-annealed at 425 °C for 3 h either in room atmosphere or under vacuum. If all the films are p-type, it is shown that the NiO films conductivity and optical transmittance depend on annealing process. The properties of the NiO thin films annealed under room atmosphere are not significantly modified, which is attributed to the fact that the temperature and the environment of this annealing is not very different from the experimental conditions during spray deposition. The annealing under vacuum is more efficient. This annealing being proceeded in a vacuum no better than 10 -2 Pa, it is supposed that the modifications of the NiO thin film properties, mainly the conductivity and optical transmission, are related to some interaction between residual oxygen and the films.

  16. Synthesis of nanocrystalline Cu2ZnSnS4 thin films grown by the spray-pyrolysis technique

    NASA Astrophysics Data System (ADS)

    Chandel, Tarun; Singh, Joginder; Rajaram, P.

    2015-08-01

    Spray pyrolysis was used to deposit Cu2ZnSnS4 (CZTS) thin films on soda lime glass substrates at 300 °C. Aqueous solutions of copper chloride, zinc chloride, stannous chloride and thiourea were mixed together to form the spray liquid. The sprayed films were annealed under vacuum at 350 °C, 400 °C and 450 °C. Structural and optical characterization was performed on the CZTS films using X-ray diffraction (XRD) and UV-VIS spectrophotometry. XRD results indicate that the films are single phase nanocrystalline CZTS. Optical studies show that the optical gap values are 1.44 eV for the as-grown film and 1.46 eV, 1.48 eV and 1.49 eV for the films annealed at 350 °C, 400 °C and 450 °C, respectively.

  17. p-TYPE Nitrogen-Doped ZnO Microrods Preparation by Spray Pyrolysis

    NASA Astrophysics Data System (ADS)

    Zahedi, F.; Dariani, R. S.; Rozati, S. M.

    2012-10-01

    Nitrogen doped ZnO films with different N/Zn atomic ratio have been prepared by spray pyrolysis technique on glass substrate at 500°C. N/Zn atomic ratio has been selected 0, 0.5, 1, 2 and 3. The effect of N/Zn ratio on structural, optical and electrical properties has been investigated. Hall effect measurement studies show that the conductivity type of the films is affected by N/Zn ratio. The conductivity type of films changes from n for N/Zn = 0 and 0.5 to p for N/Zn = 1 and 2. Further increasing in N/Zn to 3 again led to n-type conductivity. p-type ZnO:N microrods film prepared with N/Zn = 1 has highest carrier concentration (1.36 × 1016 cm-3) and lowest resistivity (628 Ω.cm). All films are polycrystalline with hexagonal wurtzite structure. (002) plane is preferential orientation for all films. Surface morphology changes from rods to grains by increasing in N/Zn ratio. Optical transmission of the films increases with increasing in N/Zn ratio. Photoluminescence spectra at room temperature show the ultraviolet emission and two visible emissions at 440 nm and 520 nm. X-ray photoelectron spectroscopy analysis confirms the incorporation of nitrogen in ZnO:N film with N/Zn = 1.

  18. Hierarchical porous carbon by ultrasonic spray pyrolysis yields stable cycling in lithium-sulfur battery.

    PubMed

    Jung, Dae Soo; Hwang, Tae Hoon; Lee, Ji Hoon; Koo, Hye Young; Shakoor, Rana A; Kahraman, Ramazan; Jo, Yong Nam; Park, Min-Sik; Choi, Jang Wook

    2014-08-13

    Utilizing the unparalleled theoretical capacity of sulfur reaching 1675 mAh/g, lithium-sulfur (Li-S) batteries have been counted as promising enablers of future lithium ion battery (LIB) applications requiring high energy densities. Nevertheless, most sulfur electrodes suffer from insufficient cycle lives originating from dissolution of lithium polysulfides. As a fundamental solution to this chronic shortcoming, herein, we introduce a hierarchical porous carbon structure in which meso- and macropores are surrounded by outer micropores. Sulfur was infiltrated mainly into the inner meso- and macropores, while the outer micropores remained empty, thus serving as a "barricade" against outward dissolution of long-chain lithium polysulfides. On the basis of this systematic design, the sulfur electrode delivered 1412 mAh/g sulfur with excellent capacity retention of 77% after 500 cycles. Also, a control study suggests that even when sulfur is loaded into the outer micropores, the robust cycling performance is preserved by engaging small sulfur crystal structures (S2-4). Furthermore, the hierarchical porous carbon was produced in ultrahigh speed by scalable spray pyrolysis. Each porous carbon particle was synthesized through 5 s of carrier gas flow in a reaction tube.

  19. CTAB assisted growth and characterization of nanocrystalline CuO films by ultrasonic spray pyrolysis technique

    NASA Astrophysics Data System (ADS)

    Singh, Iqbal; Kaur, Gursharan; Bedi, R. K.

    2011-09-01

    An aqueous solution of cupric nitrate trihydrate (Cu(NO 3) 2·3H 2O) modified with cetyltrimetylammonium bromide (CTAB) is used to deposit CuO films on glass substrate by chemical spray pyrolysis technique. The thermal analysis shows that the dried CTAB doped precursor decomposes by an exothermic reaction and suggests that minimum substrate temperature for film deposition should be greater than 270 °C. X-ray diffraction (XRD) studies indicate the formation of monoclinic CuO with preferential orientation along (0 0 2) plane for all film samples. The CTAB used as cationic surfactant in precursor results in the suppression of grain growth in films along the (1 1 0), (0 2 0) and (2 2 0) crystal planes of CuO. Surfactant modified films showed an increase in crystallite size of 14 nm at substrate temperature of 300 °C. The scanning electron micrographs (FESEM) confirm the uniform distribution of facets like grains on the entire area of substrate. CTAB modified films show a significant reduction in the particle agglomeration. Electrical studies of the CuO films deposited at substrate temperature of 300 °C with and without surfactant reveal that the CTAB doping increase the activation energy of conduction by 0.217 eV and room temperature response to ammonia by 9%. The kinetics of the ammonia gas adsorption on the film surface follows the Elovich and Diffusion models.

  20. Effects of Mn Doping on Zinc Oxide Films Prepared by Spray Pyrolysis Technique

    NASA Astrophysics Data System (ADS)

    Singh, Bhavana; Shrivastava, S. B.; Ganesan, V.

    The work deals with the preparation of Zinc Oxide (ZnO) thin films on microscopic glass substrate by spray pyrolysis technique. The systematic study on the influence of Mn doping up to 15% has been performed. The structural studies revealed that pure and doped film has hexagonal structure. In order to reduce the internal strain due to Mn doping, the crystallite size decreases. The atomic force microscopy (AFM) measurement shows the decrease in grain size and roughness with doping. The resistivity curve shows a clear hump corresponding to smaller Mn doping (x=0.5-4%) around T˜340-365 K. This hump was found to reduce with the increase in Mn concentration and for x≥7.5, beyond which it vanishes completely. This is attributed to critical behavior of resistivity and may be due to the scattering of carriers by magnetic spin fluctuation via exchange interaction. The optical measurement shows the shift in absorption edge of Mn doped ZnO films toward the longer wavelength side. This correlates the reduction in grain size as a function of Mn concentration. The optical bandgap goes down, whereas refractive index increases with dopant concentration.

  1. Photoelectrochemical performance of W-doped BiVO4 thin films deposited by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Holland, S. Keith; Dutter, Melissa R.; Lawrence, David J.; Reisner, Barbara A.; DeVore, Thomas C.

    2014-01-01

    The effects of tungsten doping and hydrogen annealing on the photoelectrochemical (PEC) performance of bismuth vanadate (BiVO4) photoanodes for solar water splitting were studied. Thin films of BiVO were deposited on indium tin oxide-coated glass slides by ultrasonic spray pyrolysis of an aqueous solution containing bismuth nitrate and vanadium oxysulfate. Tungsten doping was achieved by adding either silicotungstic acid (STA) or ammonium metatungstate (AMT) to the precursor. The 1.7- to 2.2-μm-thick films exhibited a highly porous microstructure. Undoped films that were reduced at 375°C in 3% H exhibited the largest photocurrent densities under 0.1 W cm-2 AM1.5 illumination, where photocurrent densities of up to 1.3 mA cm-2 at 0.5 V with respect to Ag/AgCl were achieved. Films doped with 1% or 5% (atomic percent) tungsten from either STA or AMT exhibited reduced PEC performance and greater sample-to-sample performance variations. Powder x-ray diffraction data indicated that the films continue to crystallize in the monoclinic polymorph at low doping levels but crystallize in the tetragonal scheelite structure at higher doping. It is surmised that the phase and morphology differences promoted by the addition of W during the deposition process reduced the PEC performance as measured by photovoltammetry.

  2. Investigation on vanadium oxide thin films deposited by spray pyrolysis technique

    NASA Astrophysics Data System (ADS)

    Margoni, Mudaliar Mahesh; Mathuri, S.; Ramamurthi, K.; Babu, R. Ramesh; Sethuraman, K.

    2016-05-01

    Vanadium oxide thin films were deposited at 400 °C by spray pyrolysis technique using 0.1 M aqueous precursor solution of ammonium meta vanadate (AMV) with two different pH values. X-ray diffraction results showed that the film prepared using aqueous precursor AMV solution (solution A; pH 7) is amorphous in nature and the film prepared by adding HNO3 in the AMV aqua solution A (solution B; pH 3) is polycrystalline in nature. Vanadium oxide film prepared from the precursor solution B is in the mixed phases of V2O5 and V4O7. Crystallinity is improved for the film prepared using solution B when compared to film prepared from solution A. Crystallite size, strain and dislocation density calculated for the film prepared from solution B is respectively 72.1 nm, 0.4554 × 10-3 lin.-2m-4 and 1.7263 × 1014 lin.m-2. Morphology study revealed that the size of the flakes formed on the surface of the films is influenced by the pH of the precursor solution. Average Visible Transmittance and maximum transmittance of the deposited films exceed 70% and the direct optical band gap value calculated for the films deposited from A and B solution is 1.91 eV and 2.08 eV respectively.

  3. Spray pyrolysis synthesis of ZnS nanoparticles from a single-source precursor.

    PubMed

    Liu, Sha; Zhang, Hongwang; Swihart, Mark T

    2009-06-10

    ZnS, a II-VI semiconductor with a relatively high direct bandgap (approximately 3.6 eV) in the near-UV region, has potential applications in areas such as solar cells, lasers and displays. In addition, ZnS nanoparticles can be applied as phosphors, probes for bioimaging, emitters in light emitting diodes and photocatalysts. Here, we report synthesis of cubic ZnS nanoparticles from a low-cost single-source precursor in a continuous spray pyrolysis reactor. In this approach, the evaporation and decomposition of precursor and nucleation of particles occur sequentially. Product particles were characterized by HRTEM, XRD, and EDX. Particles with diameters ranging from 2 to 7 nm were produced. HF was used to remove ZnO impurities and other surface contamination. As-synthesized ZnS nanoparticles exhibit blue photoluminescence near 440 nm under UV excitation and have quantum yields up to 15% after HF treatment. This demonstrates a potentially general approach for continuous low-cost synthesis of semiconductor quantum dots for applications where tight control of the size distribution is less important than scalable, economical production.

  4. Hydrophilic CdSe thin films by low cost spray pyrolysis technique and annealing effects

    NASA Astrophysics Data System (ADS)

    Logu, T.; Sankarasubramanian, K.; Soundarrajan, P.; Sethuraman, K.

    2015-03-01

    Cadmium selenide (CdSe) thin films were deposited on glass substrates at 200°C by homemade chemical spray pyrolysis technique. The as-deposited films were annealed in air atmosphere for 3 hrs, at two different temperatures (350 and 450°C). The as-deposited film has been observed to possess uniform surface with crystalline sphalerite cubic structure and optical band gap of E g = 2.4 eV. It is worth noting that after annealing, metastable cubic sphalerite phase transforms into stable well crystalline hexagonal wurtzite phase. The optical band gap was found to decrease from 2.4 eV to 1.75 eV. The average surface roughness is 1.5 nm for the as-deposited film which rises to 4.2 nm after annealing the film in air atmosphere. The contact angle was found to vary from 94° ± 1° to 81° ± 1° with annealing temperature. In addition, from Wenzel's relation it is concluded that CdSe thin film is hydrophilic in nature. [Figure not available: see fulltext.

  5. Comparative study of ITO and FTO thin films grown by spray pyrolysis

    SciTech Connect

    Ait Aouaj, M.; Diaz, R.; Belayachi, A.; Rueda, F.; Abd-Lefdil, M.

    2009-07-01

    Tin doped indium oxide (ITO) and fluorine doped tin oxide (FTO) thin films have been prepared by one step spray pyrolysis. Both film types grown at 400 deg. C present a single phase, ITO has cubic structure and preferred orientation (4 0 0) while FTO exhibits a tetragonal structure. Scanning electron micrographs showed homogeneous surfaces with average grain size around 257 and 190 nm for ITO and FTO respectively. The optical properties have been studied in several ITO and FTO samples by transmittance and reflectance measurements. The transmittance in the visible zone is higher in ITO than in FTO layers with a comparable thickness, while the reflectance in the infrared zone is higher in FTO in comparison with ITO. The best electrical resistivity values, deduced from optical measurements, were 8 x 10{sup -4} and 6 x 10{sup -4} {Omega} cm for ITO (6% of Sn) and FTO (2.5% of F) respectively. The figure of merit reached a maximum value of 2.15 x 10{sup -3} {Omega}{sup -1} for ITO higher than 0.55 x 10{sup -3} {Omega}{sup -1} for FTO.

  6. Synthesis of CuInS2 thin films by spray pyrolysis deposition system

    NASA Astrophysics Data System (ADS)

    Hussain, K. M. A.; Podder, J.; Saha, D. K.

    2013-02-01

    Copper indium disulfide (CuInS2) thin films were deposited on the glass substrate by the locally made spray pyrolysis deposition system. The films were characterized by using energy dispersive analytical X-ray (EDAX) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and UV-VIS-NIR spectrophotometry. The XRD pattern indicated that the prepared CuInS2 thin films are chalcopyrite structure. Lattice parameters and FWHM values were verified by the standard values of JCPDS 270159 file. The EDAX analysis indicated the stoichiometric ratio of 1.14:1:1.88 (CIS-2) thin films. The SEM analysis showed that the average grain size of the film was 100-800 nm and that of XRD data indicate the values of 30-50 nm. The high absorption co-efficient and 1.48 eV band gap of the films indicate that the films are useful as an absorber for photovoltaic application in the solar cell.

  7. ZnO-based thin film transistors employing aluminum titanate gate dielectrics deposited by spray pyrolysis at ambient air.

    PubMed

    Afouxenidis, Dimitrios; Mazzocco, Riccardo; Vourlias, Georgios; Livesley, Peter J; Krier, Anthony; Milne, William I; Kolosov, Oleg; Adamopoulos, George

    2015-04-08

    The replacement of SiO2 gate dielectrics with metal oxides of higher dielectric constant has led to the investigation of a wide range of materials with superior properties compared with SiO2. Despite their attractive properties, these high-k dielectrics are usually manufactured using costly vacuum-based techniques. To overcome this bottleneck, research has focused on the development of alternative deposition methods based on solution-processable metal oxides. Here we report the application of spray pyrolysis for the deposition and investigation of Al2x-1·TixOy dielectrics as a function of the [Ti(4+)]/[Ti(4+)+2·Al(3+)] ratio and their implementation in thin film transistors (TFTs) employing spray-coated ZnO as the active semiconducting channels. The films are studied by UV-visible absorption spectroscopy, spectroscopic ellipsometry, impedance spectroscopy, atomic force microscopy, X-ray diffraction and field-effect measurements. Analyses reveal amorphous Al2x-1·TixOy dielectrics that exhibit a wide band gap (∼4.5 eV), low roughness (∼0.9 nm), high dielectric constant (k ∼ 13), Schottky pinning factor S of ∼0.44 and very low leakage currents (<5 nA/cm(2)). TFTs employing stoichiometric Al2O3·TiO2 gate dielectrics and ZnO semiconducting channels exhibit excellent electron transport characteristics with low operating voltages (∼10 V), negligible hysteresis, high on/off current modulation ratio of ∼10(6), subthreshold swing (SS) of ∼550 mV/dec and electron mobility of ∼10 cm(2) V(-1) s(-1).

  8. High-throughput screening of nanoparticle catalysts made by flame spray pyrolysis as hydrocarbon/NO oxidation catalysts.

    PubMed

    Weidenhof, B; Reiser, M; Stöwe, K; Maier, W F; Kim, M; Azurdia, J; Gulari, E; Seker, E; Barks, A; Laine, R M

    2009-07-08

    We describe here the use of liquid-feed flame spray pyrolysis (LF-FSP) to produce high surface area, nonporous, mixed-metal oxide nanopowders that were subsequently subjected to high-throughput screening to assess a set of materials for deNO(x) catalysis and hydrocarbon combustion. We were able to easily screen some 40 LF-FSP produced materials. LF-FSP produces nanopowders that very often consist of kinetic rather than thermodynamic phases. Such materials are difficult to access or are completely inaccessible via traditional catalyst preparation methods. Indeed, our studies identified a set of Ce(1-x)Zr(x)O(2) and Al(2)O(3)-Ce(1-x)Zr(x)O(2) nanopowders that offer surprisingly good activities for both NO(x) reduction and propane/propene oxidation both in high-throughput screening and in continuous flow catalytic studies. All of these catalysts offer activities comparable to traditional Pt/Al(2)O(3) catalysts but without Pt. Thus, although Pt-free, they are quite active for several extremely important emission control reactions, especially considering that these are only first generation materials. Indeed, efforts to dope the active catalysts with Pt actually led to lower catalytic activities. Thus the potential exists to completely change the materials used in emission control devices, especially for high-temperature reactions as these materials have already been exposed to 1500 degrees C; however, much research must be done before this potential is verified.

  9. Luminescence properties of Eu-complex formations into ordered mesoporous silica particles obtained by the spray pyrolysis process

    NASA Astrophysics Data System (ADS)

    Rocha, Lucas A.; Freiria, Janaina do C.; Caiut, José Maurício A.; Ribeiro, Sidney J. L.; Messaddeq, Younes; Verelst, Marc; Dexpert-Ghys, Jeannette

    2015-08-01

    Ordered mesoporous, highly luminescent SiO2 particles have been synthesized by spray pyrolysis from solutions containing tetraethylorthosilicate (TEOS), Eu(NO3)3.6H2O, and cetyltrimethylammonium bromide (CTAB) as structure-directing agents. The 1,10-phenantroline (Phen) molecules were coordinated in a post-synthesis step by a simple wet impregnation method. In addition, other matrices were also prepared by the encapsulation of europium complex Eu(fod)3 (where fod = 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedionato) into mesoporous silica, and then the Phen molecules were encapsulated by different impregnation steps, after which the luminescence properties were investigated. The obtained materials were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), powder x-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. Powders with polydisperse spherical grains were obtained, displaying an ordered hexagonal array of mesochannels. Luminescence results revealed that Phen molecules had been successfully coordinated as an additional ligand in the Eu(fod)3 complex into the channels of the mesoporous particles without disrupting the structure.

  10. Study of Optical and Electrical Properties of In2S3:Sn Films Deposited by Spray Pyrolysis

    NASA Astrophysics Data System (ADS)

    Kraini, M.; Bouguila, N.; Halidou, I.; Moadhen, A.; Vázquez-Vázquez, C.; López-Quintela, M. A.; Alaya, S.

    2015-07-01

    Tin-doped In2S3 films were grown by the chemical spray pyrolysis method using compressed air as a carrier gas. Tin is incorporated in the solution using SnCl4. Structural and optical properties of films were investigated by x-ray diffraction (XRD), absorption, Raman and photoluminescence spectroscopies. Field emission scanning electron microscopy (FESEM) and energy dispersive x-ray spectroscopy were used to explore the surface morphology. The properties of In2S3 thin films are influenced by Sn doping. XRD studies revealed that the deposited films were polycrystalline in nature exhibiting cubic structure and oriented preferentially towards (111). According to FESEM, the surface morphology of the films was free of defects. Raman studies showed different peaks related to In2S3 phase and did not show any secondary phases of In-Sn and Sn-S. In2S3:Sn films exhibited transparency over 60-85% in the visible and infrared regions. The optical band gap was found to vary in the range 2.71-2.58 eV for direct transitions. The room temperature photoluminescence (PL) studies revealed two PL bands, centered at 529 nm (band A) and 725 nm (band B). From these results, one can conclude that our material can be used as transmittive windows in low-cost solar cells. The conductance and capacitance characterization at ambient temperature were also investigated and gave interesting physical properties for photovoltaic applications.

  11. In vitro and in vivo antimicrobial properties of silver-containing hydroxyapatite prepared via ultrasonic spray pyrolysis route.

    PubMed

    Honda, Michiyo; Kawanobe, Yusuke; Ishii, Ken; Konishi, Toshiisa; Mizumoto, Minori; Kanzawa, Nobuyuki; Matsumoto, Morio; Aizawa, Mamoru

    2013-12-01

    Hydroxyapatite (HAp), with its high biocompatibility and osteoconductivity, readily absorbs proteins, amino acids and other substances, which in turn favor the adsorption and colonization of bacteria. To prevent bacterial growth and biofilm formation on HAp discs, silver-containing (1-20 mol%) HAp (Ag-HAp) powders were synthesized using an ultrasonic spray pyrolysis (USSP) technique. The X-ray diffraction (XRD) peaks were very broad, indicating low crystallinity, and this induced the release of Ag(+) ions from Ag-HAp powders. In addition, a gradual increase in Ca(2+) ion release was observed. These results suggest that dissolution of Ca(2+) ion in Ag-HAp triggered the release of Ag(+) ions. The antimicrobial efficacy of Ag-HAp disc was tested against Staphylococcus aureus. Samples with Ag contents of more than 5 mol% were found to be highly effective against bacterial colonization and biofilm formation in vitro. In vivo antibacterial tests using bioluminescent strains also showed reductions in the viability of bacteria with Ag-HAp (5 mol%) discs. Biocompatibility tests using a modified Transwell® insert method showed that Ag-HAp (5 mol%) discs have negative effects on osteoblast proliferation. These results indicate that Ag-HAp (5 mol%) has effective antibacterial activity and good biocompatibility both in vitro and in vivo together with good biocompatibility, thus confirming its utility as a bactericidal material.

  12. Evolution of Zinc Oxide Nanostructures Grown on Graphene by Ultrasonic Spray Pyrolysis and Its Statistical Growth Modelling.

    PubMed

    Ali, Amgad Ahmed; Hashim, Abdul Manaf

    2015-12-01

    The evolution of zinc oxide nanostructures grown on graphene by alcohol-assisted ultrasonic spray pyrolysis was investigated. The evolution of structures is strongly depended on pyrolysis parameters, i.e., precursor molarity, precursor flow rate, precursor injection/deposition time, and substrate temperature. Field-effect scanning electron microscope analysis, energy dispersive X-ray spectroscopy, X-ray diffraction, and transmission electron microscopy were used to investigate the properties of the synthesized nanostructures and to provide evidence for the structural changes according to the changes in the pyrolysis parameters. The optimum parameters to achieve maximum density and well-defined hexagonally shaped nanorods were a precursor molarity of 0.2 M, an injection flow rate of 6 ml/min, an injection time of 10 min, and a substrate temperature of 250-355 °C. Based on the experimental results, the response surface methodology (RSM) was used to model and optimize the independent pyrolysis parameters using the Box-Behnken design. Here, the responses, i.e., the nanostructure density, size, and shape factor, are evaluated. All of the computations were performed using the Design-Expert software package. Analysis of variance (ANOVA) was used to evaluate the results of the model and to determine the significant values for the independent pyrolysis parameters. The evolution of zinc oxide (ZnO) structures are well explained by the developed modelling which confirms that RSM is a reliable tool for the modelling and optimization of the pyrolysis parameters and prediction of nanostructure sizes and shapes.

  13. Influence of solution deposition rate on properties of V2O5 thin films deposited by spray pyrolysis technique

    NASA Astrophysics Data System (ADS)

    Abd-Alghafour, N. M.; Ahmed, Naser M.; Hassan, Zai; Mohammad, Sabah M.

    2016-07-01

    Vanadium oxide (V2O5) thin films were deposited on glass substrates by using a cost-efficient spray pyrolysis technique. The films were grown at 350° through thermal decomposition of VCl3 in deionized water with different solution spray rates. The high resolution X-ray diffraction results revealed the formation of nanocrystalline films having orthorhombic structures with preferential orientation along (101) direction. The spray rate influenced the surface morphology and crystallite size of the films. The crystallite size was found to increase whereas the micro-strain was decreased by increasing the spray deposition rates. The increase in crystallite size and decrease in the macrostrain resulted in an improvement in the films' crystallinity. The UV-Visible spectroscopy analysis indicated that the average transmittance of all films lies in the range 75-80 %. The band gap of V2O5 film was decreased from 2.65 to 2.46 eV with increase of the spray deposition rate from 5 ml/min to 10 ml/min. first, second, and third level headings (first level heading).

  14. Structural, optical and electrical properties of undoped and indium doped zinc oxide prepared by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Addou, M.; Moumin, A.; El Idrissi, B.; Regragui, M.; Bougrine, A.; Kachouane, A.; Monty, C.

    1999-02-01

    Thin films of transparent undoped and indium doped ZnO have been deposited using the spray pyrolysis technique. The structural, optical properties and electrical resistivity of these films are investigated as a function of substrate temperature and indium concentration in the solution. X-ray diffraction showed that the films prepared at substrate temperature greater than 300 °C exhibit the hexagonal wurtzite structure with a preferential orientation along the (002) direction. Indium doping changes the orientation of grains to the (110) direction. This result is confirmed by SEM. The composition of the films is also examined by XPS. High transmittance (80%) in the visible region and low resistivity of about 10-1 Ω.cm at room temperature are obtained for thin films prepared under optimum deposition conditions: Ts = 450 ^circC and In/Zn = 2 at.%. Des couches minces transparentes et conductrices d'oxydes de zinc (ZnO) non dopées et dopées indium ont été élaborées par pulvérisation chimique réactive en phase liquide (spray). Les propriétés structurales, optiques et électriques de ces couches ont été étudiées en fonction de certains paramètres expérimentaux tel que la température du dépôt et la concentration d'indium dans la solution. L'étude par diffraction X a montré que les couches préparées à des températures de dépôt supérieures à 300 °C ont une structure hexagonale type wurtzite avec une orientation préférentielle suivant l'axe [002]. Le dopage à l'indium change l'orientation des cristallites suivant la direction [110]. Ce résultat a été confirmé par la microscopie électronique à balayage. La résistivité électrique de l'ordre de 10-1 Ω.cm et la transmission optique de 80 % ont été obtenues pour des couches préparées dans les conditions optimales : Ts = 450 ^circC et In/Zn = 2 at.%.

  15. Thermal NDE method for thermal spray coatings

    SciTech Connect

    Green, D.R.; Schmeller, M.D.; Sulit, R.A.

    1982-01-01

    This paper describes a feasibility demonstration of a thermal scanning NDE system for thermal spray coatings. Non-bonds were detected between several types of coatings and their substrates. Aluminum anti-skid coatings having very rough surfaces were included. A technique for producing known non-bond areas for calibrating and demonstrating NDE methods was developed.

  16. Direct Preparation of Uniformly-Distributed YBa2Cu3O7-x Powders by Spray-Pyrolysis

    NASA Astrophysics Data System (ADS)

    Tohge, Noboru; Tatsumisago, Masahiro; Minami, Tsutomu; Okuyama, Kikuo; Adachi, Motoaki; Kousaka, Yasuo

    1988-06-01

    Fine powders of the compound YBa2Cu3O7-x have been prepared directly by the spray-pyrolysis of aqueous solutions of corresponding metal nitrates. The powders obtained in a temperature range of 900 to 1000°C were spherical and their diameters were uniformly distributed below 1 μm. The crystallinity of these powders was increased with increasing decomposition temperature; an orthorhombic single phase was indeed obtained at 1000°C. The sintered bodies from these powders showed the offset of superconducting transition at 84 K.

  17. One-Step Synthesis of Pt/Graphene Composites from Pt Acid Dissolved Ethanol via Microwave Plasma Spray Pyrolysis

    PubMed Central

    Jo, Eun Hee; Chang, Hankwon; Kim, Sun Kyung; Choi, Ji-Hyuk; Park, Su-Ryeon; Lee, Chong Min; Jang, Hee Dong

    2016-01-01

    Pt nanoparticles-laden graphene (Pt/GR) composites were synthesized in the gas phase from a mixture of ethanol and Pt precursor by microwave plasma spray pyrolysis. The morphology of Pt/GR composites has the shape of wrinkled sheets of paper, while Pt nanoparticles (Pt NPs) that are less than 2.6 nm in the mean diameter are uniformly well deposited on the surface of GR sheets stacked in only three layers. The Pt/GR composite prepared with 20 wt% of Pt had the highest specific surface area and electrochemical surface area of up to 402 m2 g−1 and 77 m2 g−1 (Pt), respectively. In addition, the composite showed superior electrocatalytic activity compared with commercial Pt-carbon black. The excellent electrocatalytic activity was attributed to the high specific surface area and electrochemical surface area of the Pt/GR composite directly produced by microwave plasma spray pyrolysis. Thus, it is clearly expected that the Pt/GR composite is a promising material for DMFC catalysts. PMID:27622908

  18. High-rate production of functional nanostructured films and devices by coupling flame spray pyrolysis with supersonic expansion.

    PubMed

    Wegner, K; Vinati, S; Piseri, P; Antonini, A; Zelioli, A; Barborini, E; Ducati, C; Milani, P

    2012-05-11

    The fabrication of functional thin films and devices by direct deposition of nanoparticles from the gas phase is a promising approach enabling, for instance, the integration of complex analytical and sensing capabilities on microfabricated platforms. Aerosol-based techniques ensure large-scale nanoparticle production and they are potentially suited for this goal. However, they are not adequate in terms of fine control over the lateral resolution of the coatings, mild processing conditions (avoiding high temperature and aggressive chemicals), low contamination and compatibility with microfabrication processes. Here we report the high-rate and efficient production of functional nanostructured films by nanoparticle assembling obtained by the combination of flame spray pyrolysis and supersonic expansion. Our approach merges the advantages of flame spray pyrolysis for bulk nanopowders such as process stability and wide material library availability with those of supersonic cluster beam deposition in terms of lateral resolution and of direct integration of nanomaterials on devices. We efficiently produced nanostructured films and devices (such as gas sensors) using metal oxide, pure noble metal and oxide-supported noble metal nanoparticles.

  19. Low Temperature Synthesis of Fluorine-Doped Tin Oxide Transparent Conducting Thin Film by Spray Pyrolysis Deposition.

    PubMed

    Ko, Eun-Byul; Choi, Jae-Seok; Jung, Hyunsung; Choi, Sung-Churl; Kim, Chang-Yeoul

    2016-02-01

    Transparent conducting oxide (TCO) is widely used for the application of flat panel display like liquid crystal displays and plasma display panel. It is also applied in the field of touch panel, solar cell electrode, low-emissivity glass, defrost window, and anti-static material. Fluorine-doped tin oxide (FTO) thin films were fabricated by spray pyrolysis of ethanol-added FTO precursor solutions. FTO thin film by spray pyrolysis is very much investigated and normally formed at high temperature, about 500 degrees C. However, these days, flexible electronics draw many attentions in the field of IT industry and the research for flexible transparent conducting thin film is also required. In the industrial field, indium-tin oxide (ITO) film on polymer substrate is widely used for touch panel and displays. In this study, we investigated the possibility of FTO thin film formation at relatively low temperature of 250 degrees C. We found out that the control of volume of input precursor and exhaust gases could make it possible to form FTO thin film with a relatively low electrical resistance, less than 100 Ohm/sq and high optical transmittance about 88%.

  20. One-Step Synthesis of Pt/Graphene Composites from Pt Acid Dissolved Ethanol via Microwave Plasma Spray Pyrolysis.

    PubMed

    Jo, Eun Hee; Chang, Hankwon; Kim, Sun Kyung; Choi, Ji-Hyuk; Park, Su-Ryeon; Lee, Chong Min; Jang, Hee Dong

    2016-09-13

    Pt nanoparticles-laden graphene (Pt/GR) composites were synthesized in the gas phase from a mixture of ethanol and Pt precursor by microwave plasma spray pyrolysis. The morphology of Pt/GR composites has the shape of wrinkled sheets of paper, while Pt nanoparticles (Pt NPs) that are less than 2.6 nm in the mean diameter are uniformly well deposited on the surface of GR sheets stacked in only three layers. The Pt/GR composite prepared with 20 wt% of Pt had the highest specific surface area and electrochemical surface area of up to 402 m(2) g(-1) and 77 m(2) g(-1) (Pt), respectively. In addition, the composite showed superior electrocatalytic activity compared with commercial Pt-carbon black. The excellent electrocatalytic activity was attributed to the high specific surface area and electrochemical surface area of the Pt/GR composite directly produced by microwave plasma spray pyrolysis. Thus, it is clearly expected that the Pt/GR composite is a promising material for DMFC catalysts.

  1. One-Step Synthesis of Pt/Graphene Composites from Pt Acid Dissolved Ethanol via Microwave Plasma Spray Pyrolysis

    NASA Astrophysics Data System (ADS)

    Jo, Eun Hee; Chang, Hankwon; Kim, Sun Kyung; Choi, Ji-Hyuk; Park, Su-Ryeon; Lee, Chong Min; Jang, Hee Dong

    2016-09-01

    Pt nanoparticles-laden graphene (Pt/GR) composites were synthesized in the gas phase from a mixture of ethanol and Pt precursor by microwave plasma spray pyrolysis. The morphology of Pt/GR composites has the shape of wrinkled sheets of paper, while Pt nanoparticles (Pt NPs) that are less than 2.6 nm in the mean diameter are uniformly well deposited on the surface of GR sheets stacked in only three layers. The Pt/GR composite prepared with 20 wt% of Pt had the highest specific surface area and electrochemical surface area of up to 402 m2 g‑1 and 77 m2 g‑1 (Pt), respectively. In addition, the composite showed superior electrocatalytic activity compared with commercial Pt-carbon black. The excellent electrocatalytic activity was attributed to the high specific surface area and electrochemical surface area of the Pt/GR composite directly produced by microwave plasma spray pyrolysis. Thus, it is clearly expected that the Pt/GR composite is a promising material for DMFC catalysts.

  2. Liquid-feed flame spray pyrolysis synthesis of oxide nanopowders for the processing of ceramic composites

    NASA Astrophysics Data System (ADS)

    Taylor, Nathan John

    In the liquid-feed flame spray pyrolysis (LF-FSP) process, alcohol solutions of metalloorganic precursors are aerosolized by O2 and combusted. The metal oxide combustion products are rapidly quenched (< 10 ms) from flame temperatures of 1500°C to temperatures < 400° C, limiting particle growth. The resulting nanopowders are typically agglomerated but unaggregated. Here, we demonstrate two processing approaches to dense materials: nanopowders with the exact composition, and mixed single metal oxide nanopowders. The effect of the initial degree of phase separation on the final microstructures was determined by sintering studies. Our first studies included the production of yttrium aluminum garnet, Y3Al5O12 (YAG), tubes which we extruded from a thermoplastic/ceramic blend. At equivalent final densities, we found finer grain sizes in the from the mixed Y2O3 and Al2 O3 nanopowders, which was attributed to densification occurring before full transformation to the YAG phase. The enhanced densification in production of pure YAG from the reactive sintering process led us to produce composites in the YAG/alpha-Al 2O3 system. Finally, a third Y2O3 stabilized ZrO2 (YSZ) phase was added to further refine grain sizes using the same two processing approaches. In a separate study, single-phase metastable Al2O3 rich spinels with the composition MO•3Al 2O3 where M = Mg, Ni, and Co were sintered to produce dense MAl2O4/alpha-Al2O3 composites. All of these studies provide a test of the bottom-up approach; that is, how the initial length scale of mixing affects the final composite microstructure. Overall, the length scale of mixing is highly dependent upon the specific oxide composites studied. This work provides a processing framework to be adopted by other researchers to further refine microstructural size. LF-FSP flame temperatures were mapped using different alcohols with different heats of combustion: methanol, ethanol, 1-propanol, and n-butanol. The effect of different

  3. Synthesis and characterization of nanosized calcium phosphates by flame spray pyrolysis, and their effect on osteogenic differentiation of stem cells

    NASA Astrophysics Data System (ADS)

    Ataol, Sibel; Tezcaner, Ayşen; Duygulu, Ozgur; Keskin, Dilek; Machin, Nesrin E.

    2015-02-01

    The present study evaluates the synthesis of biocompatible osteoconductive and osteoinductive nano calcium phosphate (CaP) particles by industrially applied, aerosol-derived flame spray pyrolysis method for biomedical field. Calcium phosphate nanoparticles were produced in a range of calcium-to-phosphorus ratio, (1.20-2.19) in order to analyze the morphology and crystallinity changes, and to test the bioactivity of particles. The characterization results confirmed that nanometer-sized, spherical calcium phosphate particles were produced. The average primary particle size was determined as 23 nm by counting more than 500 particles in TEM pictures. XRD patterns, HRTEM, SAED, and SEM analyses revealed the amorphous nature of the as-prepared nano calcium phosphate particles at low Ca/P ratios. Increases in the specific surface area and crystallinity were observed with the increasing Ca/P ratio. TGA-DTA analysis showed that the thermally stable crystal phases formed after 700 °C. Cell culture studies were conducted with urine-derived stem cells that possess the characteristics of mesenchymal stem cells. Synthesized amorphous nanoparticles did not have cytotoxic effect at 5-50 μg/ml concentration range. Cells treated with the as-prepared nanoparticles had higher alkaline phosphatase (ALP) enzyme activity than control cells, indicating osteogenic differentiation of cells. A slight decrease in ALP activity of cells treated with two highest Ca:P ratios at 50 μg/ml concentration was observed at day 7. The findings suggest that calcium phosphate nanoparticles produced in this work have a potential to be used as biomaterials in biomedical applications.

  4. Methods and apparatuses for deoxygenating biomass-derived pyrolysis oil

    DOEpatents

    Baird, Lance Awender; Brandvold, Timothy A.

    2015-10-20

    Embodiments of methods and apparatuses for deoxygenating a biomass-derived pyrolysis oil are provided. In one example, a method comprises the steps of separating a low-oxygen biomass-derived pyrolysis oil effluent into a low-oxygen-pyoil organic phase stream and an aqueous phase stream. Phenolic compounds are removed from the aqueous phase stream to form a phenolic-rich diluent recycle stream. A biomass-derived pyrolysis oil stream is diluted and heated with the phenolic-rich diluent recycle stream to form a heated diluted pyoil feed stream. The heated diluted pyoil feed stream is contacted with a deoxygenating catalyst in the presence of hydrogen to deoxygenate the heated diluted pyoil feed stream.

  5. Superior Na-ion storage properties of high aspect ratio SnSe nanoplates prepared by a spray pyrolysis process

    NASA Astrophysics Data System (ADS)

    Park, Gi Dae; Lee, Jong-Heun; Kang, Yun Chan

    2016-06-01

    SnSe nanoplates with thin and uniform morphology are prepared by one-pot spray pyrolysis, and are examined as anode materials for Na-ion batteries. During the spray pyrolysis process, metallic Se and Sn are prepared from SeO2 and SnO2, respectively, under a reducing atmosphere. Metallic Sn and metalloid Se, with melting points of 232 and 221 °C, respectively, form a melted Sn-Se mixture, which reacts exothermally to form SnSe nanocrystals. Several of these nanocrystals are grown simultaneously forming a micron-sized powder. Complete elimination of the excess amount of metalloid Se, by forming H2Se gas, results in aggregation-free SnSe nanoplates. The aspect ratio of these nanoplates is as high as 11.3. The discharge capacities for the SnSe nanoplates, prepared from spray solutions containing 100, 400, and 800% of the stoichiometric SeO2 content needed to form SnSe, are 407, 558, and 211 mA h g-1, respectively, after 50 cycles at a constant current density of 0.3 A g-1 their capacity retentions calculated from the second cycle onwards are 77, 100, and 60%, respectively. The phase pure SnSe nanoplates with a high aspect ratio show good cycling and rate performances for Na-ion storage.SnSe nanoplates with thin and uniform morphology are prepared by one-pot spray pyrolysis, and are examined as anode materials for Na-ion batteries. During the spray pyrolysis process, metallic Se and Sn are prepared from SeO2 and SnO2, respectively, under a reducing atmosphere. Metallic Sn and metalloid Se, with melting points of 232 and 221 °C, respectively, form a melted Sn-Se mixture, which reacts exothermally to form SnSe nanocrystals. Several of these nanocrystals are grown simultaneously forming a micron-sized powder. Complete elimination of the excess amount of metalloid Se, by forming H2Se gas, results in aggregation-free SnSe nanoplates. The aspect ratio of these nanoplates is as high as 11.3. The discharge capacities for the SnSe nanoplates, prepared from spray solutions

  6. Comparison of carrier transport mechanism under UV/Vis illumination in an AZO photodetector and an AZO/p-Si heterojunction photodiode produced by spray pyrolysis

    SciTech Connect

    Shasti, M.; Mortezaali, A. Dariani, R. S.

    2015-01-14

    In this study, Aluminum doped Zinc Oxide (AZO) layer is deposited on p-type silicon (p-Si) by spray pyrolysis method to fabricate ultraviolet-visible (UV/Vis) photodetector as Al doping process can have positive effect on the photodetector performance. Morphology, crystalline structure, and Al concentration of AZO layer are investigated by SEM, XRD, and EDX. The goal of this study is to analyze the mechanism of carrier transport by means of current-voltage characteristics under UV/Vis illumination in two cases: (a) electrodes connected to the surface of AZO layer and (b) electrodes connected to cross section of heterojunction (AZO/p-Si). Measurements indicate that the AZO/p-Si photodiode exhibits a higher photocurrent and lower photoresponse time under visible illumination with respect to AZO photodetector; while under UV illumination, the above result is inversed. Besides, the internal junction field of AZO/p-Si heterojunction plays an important role on this mechanism.

  7. Modifying Optical Properties of ZnO Films by Forming Zn[subscript 1-x] Co[subscript x]O Solid Solutions via Spray Pyrolysis

    ERIC Educational Resources Information Center

    Bentley, Anne K.; Weaver, Gabriela C.; Russell, Cianan B.; Fornes, William L.; Choi, Kyoung-Shin; Shih, Susan M.

    2007-01-01

    A simple and cost-effective experiment for the development and characterization of semiconductors using Uv-vis spectroscopy is described. The study shows that the optical properties of ZnO films can be easily modified by forming Zn[subscript 1-x] Co[subscript x]O solid solutions via spray pyrolysis.

  8. Effect of annealing on the properties of nanocrystalline CuInSSe thin films deposited by spray pyrolysis

    SciTech Connect

    Shrotriya, Vipin Rajaram, P.

    2015-08-28

    The effect of annealing CuInSSe thin films, which were grown on glass substrates using the spray pyrolysis technique from spray solutions having S/Se ionic ratio 0.6, were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and optical transmission measurements. The CuInSSe films were co-deposited from an aqueous solution containing CuCl{sub 2}, InCl{sub 3}, thiourea and SeO{sub 2}. EDC was used as a complexing agent and films were deposited at the constant temperature 300°C. Post annealing (at 350°C) was used to improve the structural, morphological and optical properties of CuInSSe thin films. From the results, it is found that the films are single phase, p-type in conductivity having the chalcopyrite structure. From the Scherrer formula the average size of the films was found to be in the range (15-28) nm. Optical studies show that the optical band gap value increases slightly from 1.35 eV to 1.37 eV with annealing for films grown from spray solutions having S/Se ionic ratio 0.6.

  9. Facile spray-drying/pyrolysis synthesis of core-shell structure graphite/silicon-porous carbon composite as a superior anode for Li-ion batteries

    NASA Astrophysics Data System (ADS)

    Li, Min; Hou, Xianhua; Sha, Yujing; Wang, Jie; Hu, Shejun; Liu, Xiang; Shao, Zongping

    2014-02-01

    A silicon/graphite/amorphous carbon (Si/C) composite with a low silicon content in a core-shell structure has been easily synthesized using a simple method based on spray drying in combination with a subsequent pyrolysis process; natural graphite serves as the core, and silicon nanoparticles, which filled in the porous carbon matrix formed from the pyrolysis of citric acid and pitch precursors, serve as the shell. The combination of the core-shell structure for the composite and porous carbon-coating layer accommodates the large volume change of the silicon during the lithium intercalation/extraction process, thus stabilizing the electrode structure during discharge/charge cycles. As an anode material, the as-obtained Si/C composite demonstrates high capacity and excellent cycle stability. An initial specific discharge capacity of approximately 723.8 mAh g-1 and a reversible specific capacity of approximately 600 mAh g-1 after 100 cycles at a constant density of 100 mA g-1 are reached, about two times the values for graphite. Due to the simple synthesis process and the excellent performance of the resulted electrode, great commercial potential is envisioned.

  10. Effect of the substrate temperature on the physical properties of molybdenum tri-oxide thin films obtained through the spray pyrolysis technique

    SciTech Connect

    Martinez, H.M.; Torres, J.; Lopez Carreno, L.D.; Rodriguez-Garcia, M.E.

    2013-01-15

    Polycrystalline molybdenum tri-oxide thin films were prepared using the spray pyrolysis technique; a 0.1 M solution of ammonium molybdate tetra-hydrated was used as a precursor. The samples were prepared on Corning glass substrates maintained at temperatures ranging between 423 and 673 K. The samples were characterized through micro Raman, X-ray diffraction, optical transmittance and DC electrical conductivity. The species MoO{sub 3} (H{sub 2}O){sub 2} was found in the sample prepared at a substrate temperature of 423 K. As the substrate temperature rises, the water disappears and the samples crystallize into {alpha}-MoO{sub 3}. The optical gap diminishes as the substrate temperature rises. Two electrical transport mechanisms were found: hopping under 200 K and intrinsic conduction over 200 K. The MoO{sub 3} films' sensitivity was analyzed for CO and H{sub 2}O in the temperature range 160 to 360 K; the results indicate that CO and H{sub 2}O have a reduction character. In all cases, it was found that the sensitivity to CO is lower than that to H{sub 2}O. - Highlights: Black-Right-Pointing-Pointer A low cost technique is used which produces good material. Black-Right-Pointing-Pointer Thin films are prepared using ammonium molybdate tetra hydrated. Black-Right-Pointing-Pointer The control of the physical properties of the samples could be done. Black-Right-Pointing-Pointer A calculation method is proposed to determine the material optical properties. Black-Right-Pointing-Pointer The MoO{sub 3} thin films prepared by spray pyrolysis could be used as gas sensor.

  11. Low oxygen biomass-derived pyrolysis oils and methods for producing the same

    DOEpatents

    Marinangeli, Richard; Brandvold, Timothy A; Kocal, Joseph A

    2013-08-27

    Low oxygen biomass-derived pyrolysis oils and methods for producing them from carbonaceous biomass feedstock are provided. The carbonaceous biomass feedstock is pyrolyzed in the presence of a catalyst comprising base metal-based catalysts, noble metal-based catalysts, treated zeolitic catalysts, or combinations thereof to produce pyrolysis gases. During pyrolysis, the catalyst catalyzes a deoxygenation reaction whereby at least a portion of the oxygenated hydrocarbons in the pyrolysis gases are converted into hydrocarbons. The oxygen is removed as carbon oxides and water. A condensable portion (the vapors) of the pyrolysis gases is condensed to low oxygen biomass-derived pyrolysis oil.

  12. Synthesis of In2S3 thin films by spray pyrolysis from precursors with different [S]/[In] ratios

    NASA Astrophysics Data System (ADS)

    Sall, Thierno; Nafidi, A.; Marí Soucase, Bernabé; Mollar, Miguel; Hartitti, Bouchaib; Fahoume, Mounir

    2014-06-01

    Indium sulfide (In2S3) thin films were prepared by chemical spray pyrolysis technique from solutions with different [S]/[In] ratios on glass substrates at a constant temperature of 250 °C. Thin films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), energy dispersive X-ray spectroscopy (EDS), Raman spectroscopy and optical transmittance spectroscopy. All samples exhibit a polycrystalline structure with a preferential orientation along (0, 0, 12). A good stoichiometry was attained for all samples. The morphology of thin film surfaces, as seen by SEM, was dense and no cracks or pinholes were observed. Raman spectroscopy analysis shows active modes belonging to β-ln2S3 phase. The optical transmittance in the visible range is higher than 60% and the band gap energy slightly increases with the sulfur to indium ratio, attaining a value of 2.63 eV for [S]/[In] = 4.5.

  13. Dopant-induced bandgap shift in Al-doped ZnO thin films prepared by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Hung-Chun Lai, Henry; Basheer, Tahseen; Kuznetsov, Vladimir L.; Egdell, Russell G.; Jacobs, Robert M. J.; Pepper, Michael; Edwards, Peter P.

    2012-10-01

    A series of 1 at. % Al-doped ZnO (AZO) films were deposited onto glass substrates by a spray pyrolysis technique. We find that the observed blue shift in the optical bandgap of 1% AZO films is dominated by the Burstein Moss effect. The Fermi level for an 807 nm thick AZO film rose by some 0.16 eV with respect to the edge of the conduction band. By controlling the film thickness, all AZO films exhibit the same lattice strain values. The influence of strain-induced bandgap shift was excluded by selecting films with nearly the same level of bandgap volume-deformation potentials, and the differences in out-plain strain and in-plain stress remained effectively constant.

  14. Selectivity Enhancement by Using Double-Layer MOX-Based Gas Sensors Prepared by Flame Spray Pyrolysis (FSP)

    PubMed Central

    Rebholz, Julia; Grossmann, Katharina; Pham, David; Pokhrel, Suman; Mädler, Lutz; Weimar, Udo; Barsan, Nicolae

    2016-01-01

    Here we present a novel concept for the selective recognition of different target gases with a multilayer semiconducting metal oxide (SMOX)-based sensor device. Direct current (DC) electrical resistance measurements were performed during exposure to CO and ethanol as single gases and mixtures of highly porous metal oxide double- and single-layer sensors obtained by flame spray pyrolysis. The results show that the calculated resistance ratios of the single- and double-layer sensors are a good indicator for the presence of specific gases in the atmosphere, and can constitute some building blocks for the development of chemical logic devices. Due to the inherent lack of selectivity of SMOX-based gas sensors, such devices could be especially relevant for domestic applications. PMID:27608028

  15. Spin wave study and optical properties in Fe-doped ZnO thin films prepared by spray pyrolysis technique

    NASA Astrophysics Data System (ADS)

    Lmai, F.; Moubah, R.; El Amiri, A.; Abid, Y.; Soumahoro, I.; Hassanain, N.; Colis, S.; Schmerber, G.; Dinia, A.; Lassri, H.

    2016-07-01

    We investigate the magnetic and optical properties of Zn1-xFexO (x = 0, 0.03, 0.05, and 0.07) thin films grown by spray pyrolysis technique. The magnetization as a function of temperature [M (T)] shows a prevailing paramagnetic contribution at low temperature. By using spin wave theory, we separate the M (T) curve in two contributions: one showing intrinsic ferromagnetism and one showing a purely paramagnetic behavior. Furthermore, it is shown that the spin wave theory is consistent with ab-initio calculations only when oxygen vacancies are considered, highlighting the key role played by structural defects in the mechanism driving the observed ferromagnetism. Using UV-visible measurements, the transmittance, reflectance, band gap energy, band tail, dielectric coefficient, refractive index, and optical conductivity were extracted and related to the variation of the Fe content.

  16. Electrical properties of Cu4ZnSnS2/ZnS heterojunction prepared by ultrasonic spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Guitouni, S.; Khammar, M.; Messaoudi, M.; Attaf, N.; Aida, M. S.

    2016-12-01

    Cu2ZnSnS4 (CZTS)/ZnS heterojunctions have been prepared by a successive deposition of ZnS and CZTS thin films by ultrasonic spray pyrolysis technique on glass substrates. The cupric chloride concentration has been varied in the starting solution in order to investigate its influence on device properties. CZTS/ZnS heterojunctions were characterized by recording their current-voltage characteristics at different temperatures. The obtained results exhibit a good rectifying behavior of the realized heterojunction. Analysis of these results yields saturation current, series resistance and ideality factor determination. From the activation energy of saturation current we inferred that the thermal emission through the barrier height is the dominant mechanism of the reverse current rather than the defects contribution.

  17. Single-Step Synthesis of Cubic Y2O3:Eu3+ Nanophosphor by Flame Spray Pyrolysis

    NASA Astrophysics Data System (ADS)

    Lee, Jae Seok; Lee, Jinhyung; Han, Hyuksu; Kumar, Purushottam; Singh, Rajiv K.

    2016-12-01

    In this report, we investigated a single-step process for formation of high crystallinity Y2O3:Eu3+ red nanophosphor by flame spray pyrolysis (FSP) without post-heat treatments. Crystallinity of as-formed nanophosphor particle was improved by addition of urea to the nitrate-based liquid precursor. Urea increased the temperature in the flame zone thus ensuring Y2O3:Eu3+ formation at higher flame temperature. Higher temperature reached during combustion of urea promoted the formation of better crystallinity, nano-sized and spherical-shaped particles. The effect of urea in the precursor to obtain high-efficiency Y2O3:Eu3+ nanophosphor was studied.

  18. Effect of annealing on the properties of Sb doped ZnO thin films prepared by spray pyrolysis technique

    SciTech Connect

    Kumar, N. Sadananda; Bangera, Kasturi V.; Shivakumar, G. K.

    2014-01-28

    Sb doped ZnO thin films have been deposited on glass substrate at 450°C using spray pyrolysis technique. The X-ray diffraction studies revealed that the as deposited films are polycrystalline in nature with (100) preferred orientation. Whereas the films annealed at 450° C for 6h show a preferential orientation along (101) direction. Crystallites size varies from 15.7 nm to 34.95 nm with annealing duration. The Scanning electron microscopic analysis shows the plane and smooth surface of the films. The optical properties of annealed films have shown a variation in the band gap between 3.37 eV and 3.19 eV. Transparency of as grown and annealed films decreases from 78 % to 65% respectively in the visible region. The electrical conductivity of the as grown film shows an increase in the electrical conductivity by one order of magnitude with increase in the annealing duration.

  19. Characterization of Al/Al 2O 3/NiO x solar absorber obtained by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Ienei, Elena; Isac, Luminita; Cazan, Cristina; Duta, Anca

    2010-11-01

    The aim of this paper is to obtain high efficient and inexpensive spectral selective solar absorbers, for solar thermal flat plat collectors using a simple technique - spray pyrolysis deposition (SPD). To achieve maximum solar absorptance and minimum thermal emittance, the following parameters are optimized: the precursor solution concentration and composition, substrate temperature and annealing treatment. The structural and morphological properties of the films were investigated by X-ray diffraction, atomic force microscopy and contact angle measurements. The thermal emittance and solar absorptance of as-deposited films were correlated with the chemical composition, crystalline structure and morphology. The results prove that coatings with excellent spectral selective properties (normal solar absorptance of 0.92 and a normal thermal emittance of 0.03) can be obtained by SPD.

  20. Studies on structural and optical properties of Cu doped CdxZn1-XS thin films by Spray Pyrolysis

    NASA Astrophysics Data System (ADS)

    Rane, D. S.; Patil, L. A.

    2012-06-01

    Cu doped CdxZn1-XS thin films have been produced by Spray Pyrolysis technique at 2750C±50C. This work describes structural, surface morphology and optical (UV-Vis) properties of as-deposited Cu doped CdxZn1-XS thin films as a function of Zn in the solution. It has been observed that CdZnS films have hexagonal structure and the grain sizes are found to increase with increasing Zn content in the solution. The energy band gap values obtained are 2.330, 2,447, 2.716, 3.044 and 3.519eV for Zn as 0, 25, 50, 75, and 100% respectively.

  1. Optical, electrical and surface properties of annealed CdO:Mg thin films prepared by spray pyrolysis

    SciTech Connect

    Karakaya, Seniye E-mail: oozbas@ogu.edu.tr; Ozbas, Omer E-mail: oozbas@ogu.edu.tr

    2013-12-16

    The use of transparent conducting oxides in optoelectronic and photovoltaic devices has encouraged research on this field in recent years. Especially, cadmium oxide is a promising material for solar cell application but also for photodiodes and gas sensors. Mg doped CdO (CdO:Mg) films have been prepared on glass substrates by the ultrasonic spray pyrolysis (USP) technique. After the production, the films have been annealed in air atmosphere at 475°C and half hour. Results on surface, optical and electrical properties of the films as a function of the thermal annealing have been reported. Thicknesses of the films have been determined by the filmetrics thin film measurement system. Transmission and absorbance spectra have been taken by UV-vis spectrophotometer. Atomic Force Microscopy (AFM) analysis indicates that the roughness of the surface decreases upon increasing Mg concentration. The minimum resistivity value of the films was 2×10{sup −3} Ω cm.

  2. Selectivity Enhancement by Using Double-Layer MOX-Based Gas Sensors Prepared by Flame Spray Pyrolysis (FSP).

    PubMed

    Rebholz, Julia; Grossmann, Katharina; Pham, David; Pokhrel, Suman; Mädler, Lutz; Weimar, Udo; Barsan, Nicolae

    2016-09-06

    Here we present a novel concept for the selective recognition of different target gases with a multilayer semiconducting metal oxide (SMOX)-based sensor device. Direct current (DC) electrical resistance measurements were performed during exposure to CO and ethanol as single gases and mixtures of highly porous metal oxide double- and single-layer sensors obtained by flame spray pyrolysis. The results show that the calculated resistance ratios of the single- and double-layer sensors are a good indicator for the presence of specific gases in the atmosphere, and can constitute some building blocks for the development of chemical logic devices. Due to the inherent lack of selectivity of SMOX-based gas sensors, such devices could be especially relevant for domestic applications.

  3. Effect of In doping on the properties and antibacterial activity of ZnO films prepared by spray pyrolysis.

    PubMed

    Manoharan, C; Pavithra, G; Dhanapandian, S; Dhamodharan, P

    2015-01-01

    Pure and In-doped ZnO thin films were deposited onto glass substrates by spray pyrolysis technique. XRD results showed that all films were polycrystalline in nature with the wurzite structure. A change in preferential orientation from (002) to (101) plane was observed with increase in content of Indium. A reduce in crystallite size was observed with increase of In content. The small sized grains with the porous nature of the film was observed from SEM analysis. AFM study depicted polycrystalline nature and uniformly distributed grains with small pores in the doped film. A decrease in band gap was noticed with increase in In content. The absence of green emission in PL spectra indicated the decreased oxygen defects. The decrease in the resistivity with increase of Hall mobility was noted for the doped film. A better antibacterial activity was observed against Staphylococcus aureus by doped ZnO thin film.

  4. Ethylene glycol assisted spray pyrolysis for the synthesis of hollow BaFe12O19 spheres

    SciTech Connect

    Xu, X; Park, J; Hong, YK; Lane, AM

    2015-04-01

    Hollow spherical BaFe12O19 particles were synthesized by spray pyrolysis from a solution containing ethylene glycol (EG) and precursors at 1000 degrees C. The effects of EG concentration on particle morphology, crystallinity and magnetic properties were investigated. The hollow spherical particles were found to consist of primary particles, and higher EG concentration led to a bigger primary particle size. EG concentration did not show much effect on the hollow particle size. Better crystallinity and higher magnetic coercivity were obtained with higher EG concentration, which is attributed to further crystallization with the heat produced from EG combustion. Saturation magnetization (emu/g) decreased with increasing EG concentration due to residual carbon from EG incomplete combustion, contributing as a non-magnetic phase to the particles. Published by Elsevier B.V.

  5. Effect of Catalytic Pyrolysis Conditions Using Pulse Current Heating Method on Pyrolysis Products of Wood Biomass

    PubMed Central

    Honma, Sensho; Hata, Toshimitsu; Watanabe, Takashi

    2014-01-01

    The influence of catalysts on the compositions of char and pyrolysis oil obtained by pyrolysis of wood biomass with pulse current heating was studied. The effects of catalysts on product compositions were analyzed using GC-MS and TEM. The compositions of some aromatic compounds changed noticeably when using a metal oxide species as the catalyst. The coexistence or dissolution of amorphous carbon and iron oxide was observed in char pyrolyzed at 800°C with Fe3O4. Pyrolysis oil compositions changed remarkably when formed in the presence of a catalyst compared to that obtained from the uncatalyzed pyrolysis of wood meal. We observed a tendency toward an increase in the ratio of polyaromatic hydrocarbons in the pyrolysis oil composition after catalytic pyrolysis at 800°C. Pyrolysis of biomass using pulse current heating and an adequate amount of catalyst is expected to yield a higher content of specific polyaromatic compounds. PMID:25614894

  6. Substrate temperature dependent studies on properties of chemical spray pyrolysis deposited CdS thin films for solar cell applications

    NASA Astrophysics Data System (ADS)

    Diwate, Kiran; Pawbake, Amit; Rondiya, Sachin; Kulkarni, Rupali; Waykar, Ravi; Jadhavar, Ashok; Rokade, Avinash; Funde, Adinath; Mohite, Kakasaheb; Shinde, Manish; Pathan, Habib; Devan, Rupesh; Jadkar, Sandesh

    2017-02-01

    Thin films of CdS have been prepared by chemical spray pyrolysis by spraying precursor solution directly onto soda lime glass (SLG) substrates. Influence of substrate temperature on structural, optical, morphological and electrical properties have been investigated by using various techniques such as low angle X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), transmission electron microscopy (TEM), UV–visible spectroscopy photoluminescence (PL) spectroscopy etc. Formation of CdS has been confirmed by low angle XRD, Raman spectroscopy and XPS analysis. XRD pattern showed that CdS films are polycrystalline, have hexagonal structure and prefer orientation of crystallites shifts from (101) to (002) with increase in substrate temperature. Raman spectroscopy revealed that exciton-phonon coupling depends on substrate temperature and hence on crystallite size. Optical band gap increased from 2.43 to 2.99 eV when substrate temperature increased from 325 to 475 ^\\circ {{C}}. Transmittance of the film also showed an increasing trend from ∼ 52 % to ∼ 80 % with increase in substrate temperature. Such high band gap and transmittance values of CdS films prepared at 475 ^\\circ {{C}} make it a useful window material in CdS/CdTe and CdS/Cu2S heterojunction solar cells. Project supported by the Department of Science and Technology (DST), Ministry of New and Renewable Energy (MNRE), Government of India, New Delhi.

  7. Apparatuses and methods for deoxygenating biomass-derived pyrolysis oil

    SciTech Connect

    Kalnes, Tom N.

    2015-12-29

    Apparatuses and methods for deoxygenating a biomass-derived pyrolysis oil are provided herein. In one example, the method comprises of dividing a feedstock stream into first and second feedstock portions. The feedstock stream comprises the biomass-derived pyrolysis oil and has a temperature of about 60.degree. C. or less. The first feedstock portion is combined with a heated organic liquid stream to form a first heated diluted pyoil feed stream. The first heated diluted pyoil feed stream is contacted with a first deoxygenating catalyst in the presence of hydrogen to form an intermediate low-oxygen pyoil effluent. The second feedstock portion is combined with the intermediate low-oxygen pyoil effluent to form a second heated diluted pyoil feed stream. The second heated diluted pyoil feed stream is contacted with a second deoxygenating catalyst in the presence of hydrogen to form additional low-oxygen pyoil effluent.

  8. Metal-insulator transition characteristics of vanadium dioxide thin films synthesized by ultrasonic nebulized spray pyrolysis of an aqueous combustion mixture

    NASA Astrophysics Data System (ADS)

    Bharathi, R.; Naorem, Rameshwari; Umarji, A. M.

    2015-08-01

    We report the synthesis of high quality vanadium dioxide (VO2) thin films by a novel spray pyrolysis technique, namely ultrasonic nebulized spray pyrolysis of aqueous combustion mixture (UNSPACM). This simple and cost effective two step process involves synthesis of a V2O5 film on an LaAlO3 substrate followed by a controlled reduction to form single phase VO2. The formation of M1 phase (P21/c) is confirmed by Raman spectroscopic studies. A thermally activated metal-insulator transition (MIT) was observed at 61 ^\\circ C, where the resistivity changes by four orders of magnitude. Activation energies for the low conduction phase and the high conduction phase were obtained from temperature variable resistance measurements. The infrared spectra also show a dramatic change in reflectance from 13% to over 90% in the wavelength range of 7-15 μ m. This indicates the suitability of the films for optical switching applications at infrared frequencies.

  9. Elaboration of Ti{sub 0.5}Pb{sub 0.5}Sr{sub 2}CaCu{sub 2}O{sub x} superconducting phases by an ultrasonic spray-pyrolysis process

    SciTech Connect

    Abraham, R.; Guenard, F.; Lebbou, K.; Trosset, S.; Cohen-Adad, M.T.; Jorda, J.L.; Couach, M.

    1998-02-01

    An ultrasonic spray-pyrolysis process has been used to prepare a homogeneous T{sub 10.5}Pb{sub 0.5}Sr{sub 2}CaCu{sub 2}O{sub x} high-temperature superconductor. Depending on experimental conditions, the grain morphology changes from platelet to cauliflower-like, contrary to the three copper layers series. The (Tl/Pb)-Sr-1212 phase has remarkable stability and does not decompose before melting. The critical temperature onset, about 80 K, is similar to that for samples prepared by the usual sintering methods.

  10. Chemical composition and temperature dependent performance of ZnO-thin film transistors deposited by pulsed and continuous spray pyrolysis

    SciTech Connect

    Ortel, Marlis; Balster, Torsten; Wagner, Veit

    2013-12-21

    Zinc oxide thin film transistors (TFTs) deposited by continuous and pulsed spray pyrolysis were investigated to analyze process kinetics which make reduction of process temperature possible. Thus, fluid mechanics, chemical composition, electrical performance, and deposition and annealing temperature were systematically analyzed. It was found that ZnO layers continuously deposited at 360 °C contained zinc oxynitrides, CO{sub 3}, and hydro carbonate groups from pyrolysis of basic zinc acetate. Statistically, every second wurtzite ZnO unit cell contained an impurity atom. The purity and performance of the ZnO-TFTs increased systematically with increasing deposition temperature due to an improved oxidation processes. At 500 °C the zinc to oxygen ratio exceeded a high value of 0.96. Additionally, the ZnO film was not found to be in a stabilized state after deposition even at high temperatures. Introducing additional subsequent annealing steps stabilizes the film and allows the reduction of the overall thermal stress to the substrate. Further improvement of device characteristics was obtained by pulsed deposition which allowed a more effective transport of the by-products and oxygen. A significant reduction of the deposition temperature by 140 °C was achieved compared to the same performance as in continuous deposition mode. The trap density close to the Fermi energy could be reduced by a factor of two to 4 × 10{sup 17} eV{sup −1} cm{sup −3} due to the optimized combustion process on the surface. The optimization of the deposition processes made the fabrication of TFTs with excellent performance possible. The mobility was high and exceeded 12 cm{sup 2}/V s, the subthreshold slope was 0.3 V dec{sup −1}, and an on-set close to the ideal value of 0 V was achieved.

  11. Synthesis of hollow cobalt oxide nanopowders by a salt-assisted spray pyrolysis process applying nanoscale Kirkendall diffusion and their electrochemical properties.

    PubMed

    Ju, Hyeon Seok; Cho, Jung Sang; Kim, Jong Hwa; Choi, Yun Ju; Kang, Yun Chan

    2015-12-21

    A new concept for preparing hollow metal oxide nanopowders by salt-assisted spray pyrolysis applying nanoscale Kirkendall diffusion is introduced. The composite powders of metal oxide and indecomposable metal salt are prepared by spray pyrolysis. Post-treatment under a reducing atmosphere and subsequent washing using distilled water produce aggregation-free metal nanopowders. The metal nanopowders are then transformed into metal oxide hollow nanopowders by nanoscale Kirkendall diffusion. Co3O4 hollow nanopowders are prepared as first target materials. A cobalt oxide-NaCl composite powder prepared by spray pyrolysis transforms into several Co3O4 hollow nanopowders by several treatment processes. The discharge capacities of the Co3O4 nanopowders with filled and hollow structures at a current density of 1 A g(-1) for the 150th cycle are 605 and 775 mA h g(-1), respectively. The hollow structure formed by nanoscale Kirkendall diffusion improves the lithium-ion storage properties of Co3O4 nanopowders.

  12. Fabrication and characterization of n-ZnO:Eu/p-ZnO:(Ag, N) homojunction by spray pyrolysis

    SciTech Connect

    Swapna, R.; Kumar, M.C. Santhosh

    2014-01-01

    Graphical abstract: In this paper authors report the fabrication of ZnO homojunction by the deposition of 2 at.% Eu doped ZnO (n-ZnO:Eu) layer grown over the 4 at.% Ag–N dual acceptor doped ZnO (p-ZnO:(Ag, N)) layer by spray pyrolysis technique. The as-grown n-type and p-type ZnO films on glass substrates have been characterized by Hall measurements, X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), UV–vis and luminescence spectroscopy techniques. Hall measurement shows that 4 at.% ZnO:(Ag, N) film exhibits p-type conductivity with high hole concentration of 2.17 × 10{sup 18} cm{sup −3} and n-type conductivity is observed in the ZnO:Eu film. The current–voltage characteristics measured from the two-layer structure show typical rectifying characteristics of p–n homojunction with a low turn on voltage of about 1.85 V. I–V characteristics of the n-ZnO:Eu/p-ZnO:(Ag, N) homojunction. - Highlights: • The n-ZnO:Eu/p-ZnO:(Ag, N) homojunction is fabricated and characterized. • Low resistive and stable p-type ZnO films are achieved by dual acceptor-doping. • Homojunction with best dual-doped ZnO film shows good rectifying characteristics. • The fabricated ZnO homojunction is suitable for optoelectronic devices. - Abstract: In the present study, the authors report the fabrication of ZnO homojunction by the deposition of 2 at.% Eu doped ZnO (n-ZnO:Eu) layer grown over the 4 at.% Ag–N dual acceptor doped ZnO (p-ZnO:(Ag, N)) layer by spray pyrolysis technique. The as-grown n-type and p-type ZnO films on glass substrates have been characterized by Hall measurements, X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), UV–vis and luminescence spectroscopy techniques. Hall measurement shows that 4 at.% ZnO:(Ag, N) film exhibits p-type conductivity with high hole concentration of 2.17 × 10{sup 18} cm{sup −3} and n-type conductivity is observed in the ZnO:Eu film. The current–voltage characteristics measured from the two

  13. SnS Thin Films Prepared by Chemical Spray Pyrolysis at Different Substrate Temperatures for Photovoltaic Applications

    NASA Astrophysics Data System (ADS)

    Sall, Thierno; Soucase, Bernabé Marí; Mollar, Miguel; Sans, Juan Angel

    2017-03-01

    The preparation and analysis of morphological, structural, optical, vibrational and compositional properties of tin monosulfide (SnS) thin films deposited on glass substrate by chemical spray pyrolysis is reported herein. The growth conditions were evaluated to reduce the presence of residual phases different to the SnS orthorhombic phase. X-ray diffraction spectra revealed the polycrystalline nature of the SnS films with orthorhombic structure and a preferential grain orientation along the (111) direction. At high substrate temperature (450°C), a crystalline phase corresponding to the Sn2S3 phase was observed. Raman spectroscopy confirmed the dominance of the SnS phase and the presence of an additional Sn2S3 phase. Scanning electron microscopy (SEM) images reveal that the SnS film morphology depends on the substrate temperature. Between 250°C and 350°C, SnS films were shaped as rounded grains with some cracks between them, while at substrate temperatures above 400°C, films were denser and more compact. Energy-dispersive x-ray spectroscopy (EDS) analysis showed that the stoichiometry of sprayed SnS films improved with the increase of substrate temperature and atomic force microscopy micrographs showed films well covered at 350°C resulting in a rougher and bigger grain size. Optical and electrical measurements showed that the optical bandgap and the resistivity decreased when the substrate temperature increased, and smaller values, 1.46 eV and 60 Ω cm, respectively, were attained at 450°C. These SnS thin films could be used as an absorber layer for the development of tandem solar cell devices due to their high absorbability in the visible region with optimum bandgap energy.

  14. SnS Thin Films Prepared by Chemical Spray Pyrolysis at Different Substrate Temperatures for Photovoltaic Applications

    NASA Astrophysics Data System (ADS)

    Sall, Thierno; Soucase, Bernabé Marí; Mollar, Miguel; Sans, Juan Angel

    2017-01-01

    The preparation and analysis of morphological, structural, optical, vibrational and compositional properties of tin monosulfide (SnS) thin films deposited on glass substrate by chemical spray pyrolysis is reported herein. The growth conditions were evaluated to reduce the presence of residual phases different to the SnS orthorhombic phase. X-ray diffraction spectra revealed the polycrystalline nature of the SnS films with orthorhombic structure and a preferential grain orientation along the (111) direction. At high substrate temperature (450°C), a crystalline phase corresponding to the Sn2S3 phase was observed. Raman spectroscopy confirmed the dominance of the SnS phase and the presence of an additional Sn2S3 phase. Scanning electron microscopy (SEM) images reveal that the SnS film morphology depends on the substrate temperature. Between 250°C and 350°C, SnS films were shaped as rounded grains with some cracks between them, while at substrate temperatures above 400°C, films were denser and more compact. Energy-dispersive x-ray spectroscopy (EDS) analysis showed that the stoichiometry of sprayed SnS films improved with the increase of substrate temperature and atomic force microscopy micrographs showed films well covered at 350°C resulting in a rougher and bigger grain size. Optical and electrical measurements showed that the optical bandgap and the resistivity decreased when the substrate temperature increased, and smaller values, 1.46 eV and 60 Ω cm, respectively, were attained at 450°C. These SnS thin films could be used as an absorber layer for the development of tandem solar cell devices due to their high absorbability in the visible region with optimum bandgap energy.

  15. Nanofiber spraying method using a supplementary electrode

    NASA Astrophysics Data System (ADS)

    Kim, GeunHyung; Kim, WanDoo

    2006-07-01

    Using a supplementary electrode, electrospun poly(ɛ-carprolactone) fibers were deposited on various substrates with different electrical properties. The ability to coat the substrates was independent of the surface electric resistance of the substrates. This was due to the charge reduction of the sprayed fibers, which resulted from passing through the supplementary electrode. The sprayed fibers might find applications in smart textiles, advanced coating technology, and as biomedical wound dressings.

  16. Effects of drying control chemical additive on properties of Li 4Ti 5O 12 negative powders prepared by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Ju, Seo Hee; Kang, Yun Chan

    High-density Li 4Ti 5O 12 powders comprising spherical particles are prepared by spray pyrolysis from a solution containing dimethylacetamide (drying control chemical additive) and citric acid and ethylene glycol (organic additives). The prepared powders have high discharge capacities and good cycle properties. The optimum concentration of dimethylacetamide is 0.5 M. The addition of dimethylacetamide to the polymeric spray solutions containing citric acid and ethylene glycol helps in the effective control of the morphology of the Li 4Ti 5O 12 powders. At a constant current density of 0.17 mA g -1, the initial discharge capacities of the powders obtained from the spray solution with and without the organic additives are 171 and 167 mAh g -1, respectively.

  17. Synthesis of nanocrystalline Cu{sub 2}ZnSnS{sub 4} thin films grown by the spray-pyrolysis technique

    SciTech Connect

    Chandel, Tarun Singh, Joginder; Rajaram, P.

    2015-08-28

    Spray pyrolysis was used to deposit Cu{sub 2}ZnSnS{sub 4} (CZTS) thin films on soda lime glass substrates at 300 °C. Aqueous solutions of copper chloride, zinc chloride, stannous chloride and thiourea were mixed together to form the spray liquid. The sprayed films were annealed under vacuum at 350 °C, 400 °C and 450 °C. Structural and optical characterization was performed on the CZTS films using X-ray diffraction (XRD) and UV-VIS spectrophotometry. XRD results indicate that the films are single phase nanocrystalline CZTS. Optical studies show that the optical gap values are 1.44 eV for the as-grown film and 1.46 eV, 1.48 eV and 1.49 eV for the films annealed at 350 °C, 400 °C and 450 °C, respectively.

  18. Optical, Electrical, and Morphological Effects of Yttrium Doping of Cadmium Oxide Thin Films Grown by Ultrasonic Spray Pyrolysis

    NASA Astrophysics Data System (ADS)

    Tombak, Ahmet; Baturay, Silan; Kilicoglu, Tahsin; Ocak, Yusuf Selim

    2016-11-01

    CdO films doped with Y concentrations of 0%, 1%, 2%, and 3% were deposited onto soda lime glass using ultrasonic spray pyrolysis. The effect of the doping level on the structural, morphological, optical, and electrical properties of the films was characterized. X-ray diffraction analysis was used to establish that all of the samples were polycrystalline and to determine the structural parameters, i.e., lattice spacing (d), phases and associated (hkl) planes, grain size (D), and dislocation density (δ). The films possessed high conductivity and carrier concentration, showing n-type semiconducting behavior. The films were almost transparent over the range from 600 nm to 1100 nm. The energy bandgap was 2.43 eV, 2.53 eV, 2.68 eV, and 2.70 eV for Y doping of 0%, 1%, 2%, and 3%, respectively. The refractive index and extinction coefficient of the films over the range from 700 nm to 1100 nm were determined by spectroscopic ellipsometry. Atomic force microscopy revealed the effect of Y doping on the surface morphology of the CdO films.

  19. Growth of tin oxide thin films composed of nanoparticles on hydrophilic and hydrophobic glass substrates by spray pyrolysis technique

    NASA Astrophysics Data System (ADS)

    Paloly, Abdul Rasheed; Satheesh, M.; Martínez-Tomás, M. Carmen; Muñoz-Sanjosé, Vicente; Rajappan Achary, Sreekumar; Bushiri, M. Junaid

    2015-12-01

    In this paper, we have demonstrated the growth of tin oxide (SnO2) thin films composed of nanoparticles on hydrophobic (siliconized) and hydrophilic (non-siliconized) glass substrates by using the spray pyrolysis technique. X-ray diffraction (XRD) analysis confirmed the formation of SnO2 thin films with tetragonal rutile-phase structure. Average particle size of nanoparticles was determined to be in the range of 3-4 nm measured from the front view images obtained by a field emission gun scanning electron microscope (FESEM), while the size of nanoparticle clusters, when present, were in the range of 11-20 nm. Surface morphology of SnO2 films grown over hydrophobic substrates revealed larger isolated particles which are less crowded compared to the highly crowded and agglomerated smaller particles in films on hydrophilic substrates. Blue shift in the band gap is observed in samples in which the average particle size is slightly larger than the exciton Bohr radius. Photoluminescence (PL) analysis of samples grown over hydrophobic substrates exhibited an intense defect level emission and a weak near band edge emission. The enhanced visible emission from these SnO2 thin films is attributed to lattice defects formed during the film growth due to the mismatch between the film and the hydrophobic substrate surface.

  20. Photoelectrochemical performance of W-doped BiVO4 thin-films deposited by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Holland, Stephen K.; Dutter, Melissa R.; Lawrence, David J.; Reisner, Barbara A.; DeVore, Thomas C.

    2013-09-01

    The effect of tungsten doping and hydrogen annealing treatments on the photoelectrochemical (PEC) performance of bismuth vanadate (BiVO4) photoanodes for solar water splitting was studied. Thin films of BiVO4 were deposited on ITO-coated glass slides by ultrasonic spray pyrolysis of an aqueous solution containing bismuth nitrate and vanadium oxysulfate. Tungsten doping was achieved by adding either silicotungstic acid (STA) or ammonium metatungstate (AMT) in the aqueous precursor. The 1.7 μm - 2.2 μm thick films exhibited a highly porous microstructure. Undoped films that were reduced at 375 ºC in 3% H2 exhibited the largest photocurrent densities under 0.1 W cm-2 AM1.5 illumination. This performance enhancement was believed to be due to the formation of oxygen vacancies, which are shallow electron donors, in the films. Films doped with 1% or 5% tungsten from either STA or AMT exhibited reduced photoelectrochemical performance and greater sample-to-sample performance variations. Powder X-ray diffraction data of the undoped films indicated that they were comprised primarily of the monoclinic scheelite phase while unidentified phases were also present. Scanning electron microscopy showed slightly different morphology characteristics for the Wdoped films. It is surmised that the addition of W in the deposition process promoted the morphology differences and the formation of different phases, thus reducing the PEC performance of the photoanode samples. Significant PEC performance variability was also observed among films deposited using the described process.

  1. Optical and electrical properties of lithium doped nickel oxide films deposited by spray pyrolysis onto alumina substrates

    NASA Astrophysics Data System (ADS)

    Garduño, I. A.; Alonso, J. C.; Bizarro, M.; Ortega, R.; Rodríguez-Fernández, L.; Ortiz, A.

    2010-11-01

    Non-doped and lithium doped nickel oxide crystalline films have been prepared onto quartz and crystalline alumina substrates at high substrate temperature (600 °C) by the pneumatic spray pyrolysis process using nickel and lithium acetates as source materials. The structure of all the deposited films was the crystalline cubic phase related to NiO, although this crystalline structure was a little bit stressed for the films with higher lithium concentration. The grain size had values between 60 and 70 nm, almost independently of doping concentration. The non-doped and lithium doped films have an energy band gap of the order of 3.6 eV. Hot point probe results show that all deposited films have a p-type semiconductor behavior. From current-voltage measurements it was observed that the electrical resistivity decreases as the lithium concentration increases, indicating that the doping action of lithium is carried out. The electrical resistivity changed from 10 6 Ω cm for the non-doped films up to 10 2 Ω cm for the films prepared with the highest doping concentration.

  2. Nickel-induced microwheel-like surface morphological evolution of ZnO thin films by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Tarwal, N. L.; Shinde, P. S.; Oh, Y. W.; Cerc Korošec, Romana; Patil, P. S.

    2012-11-01

    Nickel-zinc oxide (Ni-ZnO) thin films were deposited onto glass and tin-doped indium oxide-coated glass substrates by using a pneumatic spray pyrolysis technique at 450 °C from aqueous solutions of zinc acetate and nickel acetate precursors. The effect of nickel doping on structural, morphological and optical properties of the ZnO thin films has been studied. The X-ray diffraction patterns confirmed the polycrystalline nature of the films having hexagonal crystal structure. Ni-ZnO films with appropriate nickel doping revealed the occurrence of novel wheel-like surface morphology. The absorption edge of the Ni-ZnO films showed a red shift, meaning that the optical band gap energy decreases as the nickel doping concentration increases. A growth model is developed and proposed for the novel wheel-like morphology. All the thin films exhibited room-temperature photoluminescence. Pure ZnO and Ni-ZnO thin films were tested for their photoelectrochemical performance in 0.5 M Na2SO4 electrolyte solution. The values of fill factor and open circuit voltage were improved for the Ni-ZnO thin films.

  3. High-performance p-n heterojunction photodetectors based on V2O5 nanorods by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Abd-Alghafour, N. M.; Ahmed, Naser. M.; Hassan, Z.; Bououdina, M.

    2016-09-01

    V2O5 heterojunction photodetector was fabricated onto Si(100) substrate using spray pyrolysis technique. Vanadium chloride (VCl3) precursor with 0.05 M concentration was used to prepare V2O5 thin film. The structural, morphological, and optical properties of V2O5 thin film were investigated. High-resolution X-ray diffraction analysis confirmed the formation of V2O5 thin film with a preferred orientation along (110) plane. Morphological observations using field emission scanning electron microscope displayed the formation of thin film with rod-like nanostructure. The optical properties examined by photoluminescence spectroscopy indicated a high-intensity visible peak centered around 530 nm. Current-voltage ( I- V) characteristics of the fabricated device under visible light exhibited low dark current and high photocurrent of 540 μA at 3 V bias voltages. Upon exposure to 560 nm visible light (24 mW/cm2) at 3 V, the device displayed a good sensitivity of 20.16 × 102. In addition, the internal gain of the photodiode was 21.16, and the photoresponse peak was 50 mA/W. The rise and recovery times of the photodiode were calculated to be 0.127 and 0.526 s under visible light (560 nm, 24 mW/cm2), respectively, at 3 V.

  4. Influence of concentration and volume of precursor on the electrochemical properties of vanadium oxide thin films prepared by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Ingole, R. S.; Fugare, B. Y.; Lokhande, B. J.

    2016-04-01

    Vanadium oxide (V2O5) thin films have been prepared by spray pyrolysis using different concentrations and volumes of precursor solution via aqueous route at 673K deposition temperature. The influences of concentration and volume on the structural, morphological and electrochemical properties of the deposited samples are studied well. X - ray diffraction study shows orthorhombic crystal structure with V2O5 phase, confirmed by FTIR spectroscopy. Scanning electron microscopy shows granular, homogeneous and dense surface morphology. Cyclic voltammetery of all samples carried at all scan rates. Samples prepared using 0.05M, 40 ml of precursor solution shows highest specific capacitance 428.25 F/gm at 5 mV/s, Charge discharge behavior exhibits specific energy 18.73 Wh/kg, specific power 36.00 kW/kg, columbic efficiency 87.50 %. Impedance spectroscopy study was carried in the frequency range 1mHz - 1MHz, reveals pseudocapacitive behavior of the electrode exhibiting internal resistance 1.34 ohm.

  5. Effect of S-doping on structural, optical and electrochemical properties of vanadium oxide thin films prepared by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Mousavi, M.; Kompany, A.; Shahtahmasebi, N.; Bagheri-Mohagheghi, M.-M.

    2013-12-01

    In this research, S-doped vanadium oxide thin films, with doping levels from 0 to 40 at.%, are prepared by spray pyrolysis technique on glass substrates. For electrochemical measurements, the films were deposited on florin-tin oxide coated glass substrates. The effect of S-doping on structural, electrical, optical and electrochemical properties of vanadium oxide thin films was studied. The x-ray diffractometer analysis indicated that most of the samples have cubic β-V2O5 phase structure with preferred orientation along [200]. With increase in the doping levels, the structure of the samples tends to be amorphous. The scanning electron microscopy images show that the structure of the samples is nanobelt-shaped and the width of the nanobelts decreases from nearly 100 to 40 nm with increase in the S concentration. With increase in the S-doping level, the sheet resistance and the optical band gap increase from 940 to 4015 kΩ/square and 2.41 to 2.7 eV, respectively. The cyclic voltammogram results obtained for different samples show that the undoped sample is expanded and the sample prepared at 20 at.% S-doping level has sharper anodic and cathodic peaks.

  6. The effect of solution concentration on the physical and electrochemical properties of vanadium oxide films deposited by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Mousavi, M.; Kompany, A.; Shahtahmasebi, N.; Bagheri-Mohagheghi, M. M.

    2013-10-01

    Vanadium oxide thin films were prepared on glass substrates by using the spray pyrolysis technique. The effect of solution concentration (0.1 M, 0.2 M and 0.3 M) on the nanostructural, electrical, optical, and electrochromic properties of deposited films were investigated using X-ray diffraction, scanning electron microscopy, UV—vis spectroscopy, and cyclic volta-metrics. The X-ray diffraction shows that only the sample at 0.1 M has a single β-V2O5 phase and the others have mixed phases of vanadium oxide. The lowest sheet resistance was obtained for the samples prepared at 0.3 M solution. It was also found that the optical transparency of the samples changes from 70% to 35% and the optical band gap of the samples was in the range of 2.20 to 2.41 eV, depending on the morality of solution. The cycle voltammogram shows that the sample prepared at 0.3 M has one-step electerochoromic but the other samples have two-step electerochoromic. The results show a correlation between the cycle voltammogram and the physical properties of the films.

  7. Electrical and morphological properties of conducting layers formed from the silver-glass composite conducting powders prepared by spray pyrolysis.

    PubMed

    Jung, D S; Koo, H Y; Kang, Y C

    2010-03-01

    Ag-glass composite powders with various glass contents and excellent conducting properties were prepared by spray pyrolysis. Irrespective of the glass content, all the prepared powders were found to comprise spherical particles with nonaggregation characteristics. The crystal structure of the powder particles resembled that of pure Ag particles, irrespective of the glass content. Conducting layers formed from pure Ag did not melt even when sintered at 400 degrees C. On the other hand, conducting layers formed from composite powders containing 3 and 5 wt% glass melted when sintered at 400 degrees C. The optimum glass content of the composite powders was 3 wt% at sintering temperatures of 400 and 450 degrees C. However, the optimum glass content decreased to 1 wt% when the sintering temperature was increased to 550 degrees C. The lowest specific resistances of the conducting layers formed from the composite powders were 5.3 and 2.3 microohms-cm at sintering temperatures of 400 and 550 degrees C, respectively.

  8. Optical, Electrical, and Morphological Effects of Yttrium Doping of Cadmium Oxide Thin Films Grown by Ultrasonic Spray Pyrolysis

    NASA Astrophysics Data System (ADS)

    Tombak, Ahmet; Baturay, Silan; Kilicoglu, Tahsin; Ocak, Yusuf Selim

    2017-04-01

    CdO films doped with Y concentrations of 0%, 1%, 2%, and 3% were deposited onto soda lime glass using ultrasonic spray pyrolysis. The effect of the doping level on the structural, morphological, optical, and electrical properties of the films was characterized. X-ray diffraction analysis was used to establish that all of the samples were polycrystalline and to determine the structural parameters, i.e., lattice spacing ( d), phases and associated ( hkl) planes, grain size ( D), and dislocation density ( δ). The films possessed high conductivity and carrier concentration, showing n-type semiconducting behavior. The films were almost transparent over the range from 600 nm to 1100 nm. The energy bandgap was 2.43 eV, 2.53 eV, 2.68 eV, and 2.70 eV for Y doping of 0%, 1%, 2%, and 3%, respectively. The refractive index and extinction coefficient of the films over the range from 700 nm to 1100 nm were determined by spectroscopic ellipsometry. Atomic force microscopy revealed the effect of Y doping on the surface morphology of the CdO films.

  9. Optical properties and mechanisms of current flow in Cu2ZnSnS4 films prepared by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Orletskii, I. G.; Mar'yanchuk, P. D.; Solovan, M. N.; Brus, V. V.; Maistruk, E. V.; Kozyarskii, D. P.; Abashin, S. L.

    2016-05-01

    Thin films Cu2ZnSnS4 (up to 0.9 μm thick) with p-type conductivity and band gap E g = 1.54 eV have been prepared by the spray pyrolysis of 0.1 M aqueous solutions of the salts CuCl2 · 2H2O, ZnCl2 · 2H2O, SnCl4 · 5H2O, and (NH2)2CS at a temperature T S = 290°C. The electrophysical properties of the films have been analyzed using the model for polycrystalline materials with electrically active grain boundaries. The energy and geometric parameters of the grain boundaries have been determined as follows: the height of the barriers is E b ≈ 0.045-0.048 eV, and the thickness of the depletion region is δ ≈ 3.25 nm. The effective concentrations of charge carriers p 0 = 3.16 × 1018 cm-3 and their mobilities in crystallites μ p = 85 cm2/(V s) have been found using the technique for determining the kinetic parameters from the absorption spectra of thin films at a photon energy hν ≈ E g . The density of states at grain boundaries N t = 9.57 × 1011 cm-2 has been estimated.

  10. Thickness-Dependent Structural and Optoelectronic Properties of In2O3 Films Prepared by Spray Pyrolysis Technique

    NASA Astrophysics Data System (ADS)

    Khan, M. A. Majeed; Khan, Wasi

    2016-08-01

    In this work, nanostructured In2O3 thin films with thickness in the range of 40-160 nm were deposited on glass substrates by the chemical spray pyrolysis technique. The microstructural, surface morphology and optical properties were investigated as a function of film thickness through x-ray diffraction, scanning electron microscopy equipped with energy dispersive spectroscopy, atomic force microscopy, Raman spectroscopy, UV-visible spectroscopy and photoluminescence measurements. The x-ray diffraction analysis showed that the deposited films were polycrystalline in nature with a cubic structure having (222) as preferred orientation. The morphological analyses of the samples exhibited uniform and smooth surface of the films with systematical increments in the surface roughness with increasing film thickness. The grain size increased from 9 nm to 13 nm with increasing film thickness. Raman spectroscopy has been employed to study the crystalline quality and the structural disorder of the films. A blue-shift in the energy band gap ( E g) from 3.74 eV to 3.98 eV was observed with the increase of film thickness. Moreover, photoluminescence peaks of the In2O3 films appeared at 443 nm and 527 nm for all films. The thickness had a substantial influence on the microstructural and optical properties as well as on the luminescence intensity of the films. The strategy presented here indicates that the prepared films could be suitable candidates for optoelectronic device applications.

  11. High-Temperature Jet Spray Reactor for the Preparation of Rare Earth Oxides by Pyrolysis: Computer Simulation

    NASA Astrophysics Data System (ADS)

    Zhao, Qiu-yue; Lv, Chao; Zhang, Zi-mu; Dou, Zhi-he; Zhang, Ting-an; Liu, Yan; Lv, Guo-zhi

    2014-09-01

    A new type of high-temperature jet spray pyrolysis (SP) reactor is investigated in this article as part of studies on the preparation of rare earth oxides at Northeastern University (NEU), Shenyang, China. The jet spray reactor examined here is a horizontal, tubular reactor conveying the hot products of the combustion of methane and oxygen with a converging-diverging jet section in an arrangement that provides for inspiration of LaCl3 solution to pyrolyze to La2O3 with the hot gas. The present article is concerned with a computer simulation using a computational fluid dynamic model to develop the velocity, temperature, and pressure profiles in the jet reactor since direct measurement is difficult. The article includes brief comments on a room-temperature model designed to examine the flow characteristics of the jet SP reactor. It was found that the velocity decreased at first, and then it increased near the jet throat. The highest velocity occurred at the throat of jet SP reactor where the LaCl3 enters the unit. Along the reactor axis, the temperature decreases with distance from the gas inlet. The lowest temperature zone was near the wall before the throat of the reactor due to wall heat losses. The temperature was estimated to be close to 1700 K at the throat of the reactor, and it was about 1300 K toward the exit of the reactor. It was shown that a reaction would take place mainly in the throat and in the vicinity of first contact between gas and induced spray. A negative pressure was produced as gas passes through the converging-diverging throat of the jet SP reactor that causes the LaCl3 solution to enter the throat of the reactor. While the investigations of this type of reactor are at an early stage, the results look promising. NEU continues to investigate this approach for the preparation of La2O3 based on high-temperature testwork and physical modeling techniques.

  12. Electrochemical properties of LiNi0.8Co0.2-xAlxO2 (0≤x≤0.1) cathode particles prepared by spray pyrolysis from the spray solutions with and without organic additives

    NASA Astrophysics Data System (ADS)

    Ju, S. H.; Kim, J. H.; Kang, Y. C.

    2010-04-01

    Fine-sized LiNi0.8Co0.2-xAlxO2 (0≤x≤0.1) cathode particles were prepared by spray pyrolysis from the spray solutions with and without organic additives. Citric acid, ethylene glycol, and Drying Control Chemical Additive (DCCA) were used as organic additives and improved the morphologies and electrochemical properties of the cathode particles. The LiNi0.8Co0.2-xAlxO2 (0≤x≤0.1) cathode particles obtained from the spray solutions with organic additives were of micro size and had slightly aggregated morphologies. The initial discharge capacities of the LiNi0.8Co0.2-xAlxO2 (0≤x≤0.1) cathode particles obtained from the spray solutions without organic additive changed from 169 mAhg-1 to 190 mAhg-1 when the x changed from 0 to 0.1. However, the initial discharge capacities of the cathode particles obtained from the spray solutions with organic additives changed from 196 mAhg-1 to 218 mAhg-1. The initial discharge capacity of the LiNi0.8Co0.15Al0.05O2 cathode particles obtained from the spray solution with organic additives was maintained after the 20th cycle at a current density of 0.1 C.

  13. Structural and magnetic characterization of LiMn{sub 1.825}Cr{sub 0.175}O{sub 4} spinel obtained by ultrasonic spray pyrolysis

    SciTech Connect

    Jugovic, D.; Kusigerski, V.; Mitric, M.; Miljkovic, M.; Makovec, D.; Uskokovic, D.

    2007-03-22

    Quaternary spinel oxide LiMn{sub 1.825}Cr{sub 0.175}O{sub 4} powder was synthesized by using an ultrasonic spray pyrolysis method, without additional annealing. The crystal structure of the as-prepared powder was revealed by X-ray powder diffraction and identified as a single spinel phase with Fd3m space group. The powders had a spherical morphology with extremely smooth surface appearance and densely congested interior structure. Transmission electron microscopy confirmed that the particle consisted by the cohesion of the primary particles. Magnetic measurements performed in DC field in both zero-field-cooled and field-cooled regimes, as well as AC susceptibility experiments, show that system undergoes spin-glass transition at the freezing temperature T {sub f} = 20 K. The value of the effective magnetic moment {mu} {sub eff} = 4.34 {mu} {sub B} obtained from the Curie-Weiss fit in the high temperature region confirms the substitution of Mn{sup 3+} ions with Cr{sup 3+} ions.

  14. Effect of variation of tin concentration on the properties of Cu2ZnSnS4 thin films deposited using chemical spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Rajeshmon, V. G.; Kuriakose, Abin; Kartha, C. Sudha; Vijayakumar, K. P.

    2013-02-01

    Cu2ZnSnS4 (CZTS) thin films were prepared using chemical spray pyrolysis technique on soda lime glass (SLG) substrates. The effect of tin concentration on the structural, optical and electrical properties was investigated. We deposited films by varying tin concentration from 0.007 M to 0.013 M in steps of 0.0015 M keeping the concentration of copper, zinc and sulphur at 0.02 M, 0.01 M and 0.12 M respectively. It was found that crystallinity of the film increased up to the tin concentration of 0.01 M and then decreases. Band gap of the films steadily decreased from 1.48 to 1.26 eV with increase in tin concentration. All the samples were observed to be p-type by hot probe method. Resistivity of the films increased with increase in tin concentration. In this work we tuned the optoelectronic properties by varying the tin concentration alone and optimized the concentration of tin which yields samples ideal for photovoltaic applications.

  15. Spray drift reduction test method correlation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ASTM Standard E609 Terminology Relating to Pesticides defines drift as “The physical movement of an agrochemical through the air at the time of application or soon thereafter to any non or off target site.” Since there are many commercial tank mix adjuvants designed to reduce spray drift, ASTM esta...

  16. Preparation of iron aluminate (FeAl2O4) nanoparticles from FeAl2O4 hollow particles fabricated by using a spray pyrolysis process

    NASA Astrophysics Data System (ADS)

    Yun, Jaecheol; Kim, Yangdo; Park, Dahee; Yun, Jung-Yeul

    2015-05-01

    Iron aluminate (FeAl2O4) hollow particles with a spinel structure were synthesized by using a spray pyrolysis process. FeAl2O4 hollow particles were formed at a reaction temperature of 900 °C at a flow rate of 40 L/min as a result of the rapid solvent evaporation and decomposition gases from the droplets in the spray solution prepared from metal salts and organic reagents. FeAl2O4 hollow particles were fabricated at a reaction temperature of 900 °C with a flow rate of 40 L/min. The FeAl2O4 hollow particles were heat treated for 3 hours at 600 °C in a 5% H2/Ar atmosphere to form the crystal particles. Subsequently, FeAl2O4 nanoparticles were fabricated from the FeAl2O4 hollow particles by using the wet milling process. After milling for 60 minutes, transmission electron microscopy revealed the FeAl2O4 particles to have a mean size of approximately 50 nm. The FeAl2O4 nanoparticles were fabricated successfully by using a two-step process, spray pyrolysis and wet milling.

  17. Pyrolysis and catalytic pyrolysis as a recycling method of waste CDs originating from polycarbonate and HIPS.

    PubMed

    Antonakou, E V; Kalogiannis, K G; Stephanidis, S D; Triantafyllidis, K S; Lappas, A A; Achilias, D S

    2014-12-01

    Pyrolysis appears to be a promising recycling process since it could convert the disposed polymers to hydrocarbon based fuels or various useful chemicals. In the current study, two model polymers found in WEEEs, namely polycarbonate (PC) and high impact polystyrene (HIPS) and their counterparts found in waste commercial Compact Discs (CDs) were pyrolysed in a bench scale reactor. Both, thermal pyrolysis and pyrolysis in the presence of two catalytic materials (basic MgO and acidic ZSM-5 zeolite) was performed for all four types of polymers. Results have shown significant recovery of the monomers and valuable chemicals (phenols in the case of PC and aromatic hydrocarbons in the case of HIPS), while catalysts seem to decrease the selectivity towards the monomers and enhance the selectivity towards other desirable compounds.

  18. Dual acceptor doping and aging effect of p-ZnO:(Na, N) nanorod thin films by spray pyrolysis

    SciTech Connect

    Swapna, R. E-mail: santhoshmc@nitt.edu; Amiruddin, R. E-mail: santhoshmc@nitt.edu; Santhosh Kumar, M. C. E-mail: santhoshmc@nitt.edu

    2014-01-28

    An attempt has been made to realize p-type ZnO by dual acceptor doping (Na-N) into ZnO thin films. Na and N doped ZnO thin films of different concentrations (0 to 8 at.%) have been grown by spray pyrolysis at 623 K. The grown films on glass substrate have been characterized by X-ray diffraction (XRD), Hall measurement, UV-Vis spectrophotometer, Photoluminescence (PL) and Energy dispersive spectroscopy (EDS) to validate the p-type conduction. The surface morphology and roughness of the ZnO:(Na, N) films are studied by scanning electron microscopy (SEM) and atomic force microscopy (AFM), respectively. Hall measurement shows that all the films exhibit p-type conductivity except for 0 at.% Na-N doped ZnO film. The obtained resistivity (5.60×10{sup −2} Ω cm) and hole concentration (3.15×10{sup 18} cm{sup −3}) for the best dual acceptor doped film is 6 at.%. It has been predicted that (Na{sub Zn}−N{sub O}) acceptor complex is responsible for the p-type conduction. The p-type conductivity of the ZnO:(Na, N) films is stable even after 6 months. The crystallinity of the films has been studied by XRD. Energy dispersive spectroscopy (EDS) confirms the presence of Na and N in 6 at.% ZnO:(Na, N) film. Photoluminescence (PL) spectra of ZnO:(Na, N) films show NBE and deep level emissions in the UV and visible regions, respectively. The ZnO:(Na, N) films exhibit a high transmittance about 90% in the visible region.

  19. Method of producing thermally sprayed metallic coating

    DOEpatents

    Byrnes, Larry Edward; Kramer, Martin Stephen; Neiser, Richard A.

    2003-08-26

    The cylinder walls of light metal engine blocks are thermally spray coated with a ferrous-based coating using an HVOF device. A ferrous-based wire is fed to the HVOF device to locate a tip end of the wire in a high temperature zone of the device. Jet flows of oxygen and gaseous fuel are fed to the high temperature zone and are combusted to generate heat to melt the tip end. The oxygen is oversupplied in relation to the gaseous fuel. The excess oxygen reacts with and burns a fraction of the ferrous-based feed wire in an exothermic reaction to generate substantial supplemental heat to the HVOF device. The molten/combusted metal is sprayed by the device onto the walls of the cylinder by the jet flow of gases.

  20. Method and apparatus for spraying molten materials

    DOEpatents

    Glovan, R.J.; Tierney, J.C.; McLean, L.L.; Johnson, L.L.; Nelson, G.L.; Lee, Y.M.

    1996-06-25

    A metal spray apparatus is provided with a supersonic nozzle. Molten metal is injected into a gas stream flowing through the nozzle under pressure. By varying the pressure of the injected metal, the droplet can be made in various selected sizes with each selected size having a high degree of size uniformity. A unique one piece graphite heater provides easily controlled uniformity of temperature in the nozzle and an attached tundish which holds the pressurized molten metal. A unique U-shaped gas heater provides extremely hot inlet gas temperatures to the nozzle. A particularly useful application of the spray apparatus is coating of threads of a fastener with a shape memory alloy. This permits a fastener to be easily inserted and removed but provides for a secure locking of the fastener in high temperature environments. 12 figs.

  1. Direct Preparation of Fine Powders of the 80 K Superconducting Phase in the Bi-Ca-Sr-Cu-O System by Spray Pyrolysis

    NASA Astrophysics Data System (ADS)

    Tohge, Noboru; Tatsumisago, Masahiro; Minami, Tsutomu; Okuyama, Kikuo; Arai, Kouji; Kousaka, Yasuo

    1989-07-01

    Submicron powders of the 80 K superconducting phase in the Bi-Ca-Sr-Cu-O system have been directly prepared by the spray pyrolysis of aqueous solutions of corresponding metal nitrates, Bi:Ca:Sr:Cu=1:1:1:2. The powders obtained were spheres with uniformly distributed diameters below 1 μm. The crystalline phase of these powders was found to greatly depend on the oxygen partial pressure in the carrier gas as well as the decomposition temperature. The preparation conditions for the 80 K superconducting phase were examined.

  2. Improved electrical, optical, and structural properties of undoped ZnO thin films grown by water-mist-assisted spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Martínez Pérez, L.; Aguilar-Frutis, M.; Zelaya-Angel, O.; Muñoz Aguirre, N.

    2006-08-01

    Undoped ZnO thin films were prepared using the ultrasonic spray pyrolysis deposition technique with zinc acetylacetonate dissolved in N,N-dimethylformamide as the source materials solution. The addition of water mist in a parallel flux to the spray solution stream was also used during deposition of the films. The addition of water mist improved the electrical characteristics of the ZnO films. Fresh ZnO samples were then thermally annealed in a H2 reducing atmosphere. X-ray diffraction patterns show mainly the wurzite crystalline ZnO phase in the films. An electrical resistivity ( ) of around 2.7 × 10-2 cm was measured at room temperature for the best undoped ZnO film. is approximately one order of magnitude lower than the resistivities found in undoped ZnO films obtained by means of similar non-vacuum deposition techniques.

  3. Synthesis of Zn1- x Co x Al2O4 Spinel Nanoparticles by Liquid-Feed Flame Spray Pyrolysis: Ceramic Pigments Application

    NASA Astrophysics Data System (ADS)

    Betancur Granados, Natalia; Yi, Eongyu; Laine, Richard M.; Restrepo Baena, Oscar Jaime

    2016-01-01

    Zn1- x Co x Al2O4 ( x = 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0) spinel nanoparticles were synthesized by a liquid-feed flame spray pyrolysis (LF-FSP) method by combusting metallorganic precursor solutions to produce nanopowders with precise composition control. The precursor solutions were aerosolized into a methane/oxygen flame where it was combusted in an oxygen-rich environment to result in nanopowders at a single step. The nanopowders were analyzed by x-ray diffraction, Fourier transform infrared spectroscopy, colorimetry, field emission scanning electron microscopy, transmission electron microscopy, and BET (Brunauer-Emmett-Teller) N2 adsorption. Results show formation of spherical nanopowders with specific surface areas of 42 m2/g to 50 m2/g, which correspond to average particle sizes of 26 nm to 31 nm. Single-phase materials were obtained with a high control of composition, which indicates that LF-FSP is an excellent method to produce mixed-metal oxides for applications in which powder homogeneity is crucial. The products were evaluated for ceramic pigment application, where the ratio of Zn to Co was gradually changed to observe the color change in the structure with the increase of cobalt concentration. The resulting pigments were calcined at 1200°C, which aimed to identify the color stability after a high-temperature process, whereby the colors were measured using the color space CIE L*a*b* under standardized light, D65. Finally, the powders were tested for ceramic decoration using transparent glazes and ceramic bodies. The application was carried out at 1250°C to evaluate the color performance after a decoration process.

  4. Method for preventing plugging in the pyrolysis of agglomerative coals

    DOEpatents

    Green, Norman W.

    1979-01-23

    To prevent plugging in a pyrolysis operation where an agglomerative coal in a nondeleteriously reactive carrier gas is injected as a turbulent jet from an opening into an elongate pyrolysis reactor, the coal is comminuted to a size where the particles under operating conditions will detackify prior to contact with internal reactor surfaces while a secondary flow of fluid is introduced along the peripheral inner surface of the reactor to prevent backflow of the coal particles. The pyrolysis operation is depicted by two equations which enable preselection of conditions which insure prevention of reactor plugging.

  5. Delicate Structural Control of Si-SiOx-C Composite via High-Speed Spray Pyrolysis for Li-Ion Battery Anodes.

    PubMed

    Lee, Seung Jong; Kim, Hye Jin; Hwang, Tae Hoon; Choi, Sunghun; Park, Sung Hyeon; Deniz, Erhan; Jung, Dae Soo; Choi, Jang Wook

    2017-03-08

    Despite the high theoretical capacity, silicon (Si) anodes in lithium-ion batteries have difficulty in meeting the commercial standards in various aspects. In particular, the huge volume change of Si makes it very challenging to simultaneously achieve high initial Coulombic efficiency (ICE) and long-term cycle life. Herein, we report spray pyrolysis to prepare Si-SiOx composite using an aqueous precursor solution containing Si nanoparticles, citric acid, and sodium hydroxide (NaOH). In the precursor solution, Si nanoparticles are etched by NaOH with the production of [SiO4](4-). During the dynamic course of spray pyrolysis, [SiO4](4-) transforms to SiOx matrix and citric acid decomposes to carbon surface layer with the assistance of NaOH that serves as a decomposition catalyst. As a result, a Si-SiOx composite, in which Si nanodomains are homogeneously embedded in the SiOx matrix with carbon surface layer, is generated by a one-pot process with a residence time of only 3.5 s in a flow reactor. The optimal composite structure in terms of Si domain size and Si-to-O ratio exhibited excellent electrochemical performance, such as reversible capacity of 1561.9 mAh g(-1) at 0.06C rate and ICE of 80.2% and 87.9% capacity retention after 100 cycles at 1C rate.

  6. One-Pot Synthesis of CoSex -rGO Composite Powders by Spray Pyrolysis and Their Application as Anode Material for Sodium-Ion Batteries.

    PubMed

    Park, Gi Dae; Kang, Yun Chan

    2016-03-14

    A simple one-pot synthesis of metal selenide/reduced graphene oxide (rGO) composite powders for application as anode materials in sodium-ion batteries was developed. The detailed mechanism of formation of the CoSe(x)-rGO composite powders that were selected as the first target material in the spray pyrolysis process was studied. The crumple-structured CoSe(x)-rGO composite powders prepared by spray pyrolysis at 800 °C had a crystal structure consisting mainly of Co0.85 Se with a minor phase of CoSe2. The bare CoSe(x) powders prepared for comparison had a spherical shape and hollow structure. The discharge capacities of the CoSe(x)-rGO composite and bare CoSe(x) powders in the 50th cycle at a constant current density of 0.3 A g(-1) were 420 and 215 mA h g(-1), respectively, and their capacity retentions measured from the second cycle were 80 and 46%, respectively. The high structural stability of the CoSe(x)-rGO composite powders for repeated sodium-ion charge and discharge processes resulted in superior sodium-ion storage properties compared to those of the bare CoSe(x) powders.

  7. Spray pyrolysis-deposited nanoengineered TiO2 thick films for ultra-high areal and volumetric capacity lithium ion battery applications

    NASA Astrophysics Data System (ADS)

    Haridas, Anupriya K.; Gangaja, Binitha; Srikrishnarka, Pillalamarri; Unni, Gautam E.; Nair, A. Sreekumaran; Nair, Shantikumar V.; Santhanagopalan, Dhamodaran

    2017-03-01

    Energy storage technologies are sensitively dependent on electrode film quality, thickness and process scalability. In Li-ion batteries, using additive-free titania (TiO2) as electrodes, we sought to show the potential of spray pyrolysis-deposited nanoengineered films with thicknesses up to 135 μm exhibiting ultra-high areal capacities. Detailed electron microscopic characterization indicated that the achieved thick films are composed of highly crystalline anatase TiO2 particles with sizes on the order of 10-12 nm and porous as well. A 135 μm thick film yielded ultra-high areal and volumetric capacities of 3.7 mAh cm-2 and 274 mAh cm-3, respectively, at 1C rate. Also the present work recorded high Coulombic efficiency and good cycling stability. The best previously achieved capacities for additive-free TiO2 films have been less than 0.25 mAh cm-2 and With additives, best reported areal capacity in the literature has been 2.5 mAh cm-2 at 1C rate, but only with electrode thickness as high as 1400 μm. Formation of through-the-thickness percolation of Ti3+ conductive network upon lithiation contributed substantially for the superior performance. Spray pyrolysis deposition of nanoparticulate TiO2 electrodes have the potential to yield volumetric capacities an order of magnitude higher than the other processes previously reported without sacrificing performance and process scalability.

  8. Evaluation of VOC emission measurement methods for paint spray booths.

    PubMed

    Eklund, B M; Nelson, T P

    1995-03-01

    Interest in regulations to control solvent emissions from automotive painting systems is increasing, especially in ozone nonattainment areas. Therefore, an accurate measurement method for VOC emissions from paint spray booths used in the automotive industry is needed to ascertain the efficiency of the spray booth capture and the total emissions. This paper presents the results of a laboratory study evaluating potential VOC sampling and analytical methods used in estimating paint spray booth emissions, and discusses these results relative to other published data. Eight test methods were selected for evaluation. The accuracy of each sampling and analytical method was determined using test atmospheres of known concentration and composition that closely matched the actual exhaust air from paint spray booths. The solvent mixture to generate the test atmospheres contained a large proportion of polar, oxygenated hydrocarbons such as ketones and alcohols. A series of identical tests was performed for each sampling/analytical method with each test atmosphere to assess the precision of the methods. The study identified significant differences among the test methods in terms of accuracy, precision, cost, and complexity.

  9. A novel gas-droplet numerical method for spray combustion

    NASA Technical Reports Server (NTRS)

    Chen, C. P.; Shang, H. M.; Jiang, Y.

    1991-01-01

    This paper presents a non-iterative numerical technique for computing time-dependent gas-droplet flows. The method is a fully-interacting combination of Eulerian fluid and Lagrangian particle calculation. The interaction calculations between the two phases are formulated on a pressure-velocity coupling procedure based on the operator-splitting technique. This procedure eliminates the global iterations required in the conventional particle-source-in-cell (PSIC) procedure. Turbulent dispersion calculations are treated by a stochastic procedure. Numerical calculations and comparisons with available experimental data, as well as efficiency assessments are given for some sprays typical of spray combustion applications.

  10. Electrical Characteristics and Preparation of (Ba0.5Sr0.5)TiO3 Films by Spray Pyrolysis and Rapid Thermal Annealing

    NASA Astrophysics Data System (ADS)

    Koo, Horng-Show; Chen, Mi; Ku, Hong-Kou; Kawai, Tomoji

    2007-04-01

    Functional films of (Ba0.5Sr0.5)TiO3 on Pt (1000 Å)/Ti (100 Å)/SiO2 (2000 Å)/Si substrates are prepared by spray pyrolysis and subsequently rapid thermal annealing. Barium nitrate, strontium nitrate and titanium isopropoxide are used as starting materials with ethylene glycol as solvent. For (Ba0.5Sr0.5)TiO3 functional thin film, thermal characteristics of the precursor powder scratched from as-sprayed films show a remarkable peak around 300-400 °C and 57.7% weight loss up to 1000 °C. The as-sprayed precursor film with coffee-like color and amorphous-like phase is transformed into the resultant film with white, crystalline perovskite phase and characteristic peaks (110) and (100). The resultant films show correspondent increases of dielectric constant, leakage current and dissipation factor with increasing annealing temperatures. The dielectric constant is 264 and tangent loss is 0.21 in the resultant films annealed at 750 °C for 5 min while leakage current density is 1.5× 10-6 A/cm2 in the film annealed at 550 °C for 5 min.

  11. Thermal nondestructive examination method for thermal-spray coatings

    SciTech Connect

    Green, D.R.; Schmeller, M.D.; Sulit, R.A.

    1983-05-01

    This paper describes a feasibility demonstration of a thermal scanning NDE (nondestructive examination) system for thermal-spray coatings. Non-bonds were detected between several types of coatings and their substrates. Aluminum anti-skid coatings having very rough surfaces were included. A technique for producing known non-bond areas for calibrating and demonstrating NDE methods was developed.

  12. Processing and synthesis of multi-metallic nano oxide ceramics via liquid-feed flame spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Azurdia, Jose Antonio

    The liquid-feed flame spray pyrolysis (LF-FSP) process aerosolizes metal-carboxylate precursors dissolved in alcohol with oxygen and combusts them at >1500°C. The products are quenched rapidly (˜10s msec) to < 400°C. By selecting the appropriate precursor mixtures, the compositions of the resulting oxide nanopowders can be tailored easily, which lends itself to combinatorial studies of systems facilitating material property optimization. The resulting nanopowders typically consist of single crystal particles with average particle sizes (APS) < 35 nm, specific surface areas (SSA) of 20-60 m2/g and spherical morphology. LF-FSP provides access to novel single phase nanopowders, known phases at compositions outside their published phase diagrams, intimate mixing at nanometer length scales in multi metallic oxide nanopowders, and control of stoichiometry to ppm levels. The materials produced may exhibit unusual properties including structural, catalytic, and photonic ones and lower sintering temperatures. Prior studies used LF-FSP to produce MgAl2O4 spinel for applications in transparent armor and IR radomes. In these studies, a stable spinel structure with a (MgO)0.1(Al2O3)0.9 composition well outside the known phase field was observed. The work reported here extends this observation to two other spinel systems: Al2O3-NiO, Al2O3-CoOx; followed by three series of transition metal binary oxides, NiO-CoO, NiO-MoO3, NiO-CuO. The impetus to study spinels derives both from the fact that a number of them are known transparent ceramics, but also others offer high SSAs coupled with unusual phases that suggest potentially novel catalytic materials. Because LF-FSP provides access to any composition, comprehensive studies of the entire tie-lines were conducted rather than just compositions of value for catalytic applications. Initial efforts established baseline properties for the nano aluminate spinels, then three binary transition metal oxide sets (Ni-Co, Ni-Mo and Ni

  13. Feasibility of thermal NDE methods for Naval thermal spray coatings

    SciTech Connect

    Green, D.R.; Wandling, C.R.; Schmeller, M.D.; Sulit, R.A.

    1983-10-24

    Thermal spray coatings are widely used to prevent corrosion in metal structures. They are also used to repair and reduce wear in machinery. A feasibility demonstration has shown that infrared-thermal scanning can be applied to nondestructively examine the coating-to-substrate bonds in a variety of thermal spray coatings. Emissivity independent and thermal wave methods must be applied in some cases to eliminate the effects of local differences in surface conditions and coating thickness. Rough-surfaced coatings such as those used in anti-skid applications can have thickness varying from about 0.1 inch (3 mm) at peaks to less than 0.04 inch (1 mm) at valleys. Data showing the feasibility of detecting non-bonds even under such rough coatings is described in this paper. The present work is the first phase of a program to develop a generally applicable emissivity independent thermal NDE scanning system for thermal spray coatings. This work was sponsored by the US Naval Sea Systems Command Materials Research and Development Program. It was directed by the Puget Sound Naval Shipyard which is the lead shipyard for introduction and implementation of industrial thermal spray processes and equipment for Naval applications. High speed, low application cost, high reliability and ease of test interpretation are the prime goals for the final thermal scanning NDE system. The most advanced state-of-the-art methods using thermal wave analysis to make maximum use of the scan information are being incorporated.

  14. The Effect of Film Composition on the Texture and Grain Size of CuInS2 Prepared by Spray Pyrolysis

    NASA Technical Reports Server (NTRS)

    Jin, Michael H.-C.; Banger, Kulbinder K.; Harris, Jerry D.; Hepp, Aloysius F.

    2003-01-01

    CuInS2 was deposited by spray pyrolysis using single-source precursors synthesized in-house. Films with either (112) or (204/220) preferred orientation always showed Cu-rich and In-rich composition respectively. The In-rich (204/220)-oriented films always contained a secondary phase evaluated as an In-rich compound, and the hindrance of (112)-oriented grain growth was confirmed by glancing angle X-ray diffraction. In conclusion, only the Cu-rich (112)-oriented films with dense columnar grains can be prepared without the secondary In-rich compound. The effect of extra Cu on the grain size and the solar cell results will be also presented.

  15. High electron mobility thin-film transistors based on Ga{sub 2}O{sub 3} grown by atmospheric ultrasonic spray pyrolysis at low temperatures

    SciTech Connect

    Thomas, Stuart R. E-mail: thomas.anthopoulos@imperial.ac.uk; Lin, Yen-Hung; Faber, Hendrik; Anthopoulos, Thomas D. E-mail: thomas.anthopoulos@imperial.ac.uk; Adamopoulos, George; Sygellou, Labrini; Stratakis, Emmanuel; Pliatsikas, Nikos; Patsalas, Panos A.

    2014-09-01

    We report on thin-film transistors based on Ga{sub 2}O{sub 3} films grown by ultrasonic spray pyrolysis in ambient atmosphere at 400–450 °C. The elemental, electronic, optical, morphological, structural, and electrical properties of the films and devices were investigated using a range of complementary characterisation techniques, whilst the effects of post deposition annealing at higher temperature (700 °C) were also investigated. Both as-grown and post-deposition annealed Ga{sub 2}O{sub 3} films are found to be slightly oxygen deficient, exceptionally smooth and exhibit a wide energy bandgap of ∼4.9 eV. Transistors based on as-deposited Ga{sub 2}O{sub 3} films show n-type conductivity with the maximum electron mobility of ∼2 cm{sup 2}/V s.

  16. The Effect of Film Composition on the Texture and Grain Size of CuInS2 Prepared by Spray Pyrolysis

    NASA Technical Reports Server (NTRS)

    Jin, Michael H.; Banger, Kulinder K.; Harris, Jerry D.; Hepp, Aloysius F.

    2003-01-01

    Ternary single-source precursors were used to deposit CuInS2 thin films using chemical spray pyrolysis. We investigated the effect of the film composition on texture, secondary phase formation, and grain size. As-grown films were most often In-rich. They became more (204/220)-oriented as indium concentration increased, and always contained a yet unidentified secondary phase. The (112)-prefened orientation became more pronounced as the film composition became more Cu-rich. The secondary phase was determined to be an In-rich compound based on composition analysis and Raman spectroscopy. In addition, as-grown Cu-rich (112)-oriented films did not exhibit the In-rich compound. Depositing a thin Cu layer prior to the growth of CuInS2 increased the maximum grain size from - 0.5 micron to - 1 micron, and prevented the formation of the In-rich secondary phase.

  17. Ionization potentials of transparent conductive indium tin oxide films covered with a single layer of fluorine-doped tin oxide nanoparticles grown by spray pyrolysis deposition

    SciTech Connect

    Fukano, Tatsuo; Motohiro, Tomoyoshi; Ida, Takashi; Hashizume, Hiroo

    2005-04-15

    Indium tin oxide (ITO) films deposited with single layers of monodispersive fluorine-doped tin oxide (FTO) nanoparticles of several nanometers in size were grown on glass substrates by intermittent spray pyrolysis deposition using conventional atomizers. These films have significantly higher ionization potentials than the bare ITO and FTO films grown using the same technique. The ITO films covered with FTO particles of 7 nm in average size show an ionization potential of 5.01 eV, as compared with {approx}4.76 and {approx}4.64 eV in ITO and FTO films, respectively, which decreases as the FTO particle size increases. The ionization potentials are practically invariant against oxidation and reduction treatments, promising a wide application of the films to transparent conducting oxide electrodes in organic electroluminescent devices and light-emitting devices of high efficiencies.

  18. Method of producing pyrolysis gases from carbon-containing materials

    DOEpatents

    Mudge, Lyle K.; Brown, Michael D.; Wilcox, Wayne A.; Baker, Eddie G.

    1989-01-01

    A gasification process of improved efficiency is disclosed. A dual bed reactor system is used in which carbon-containing feedstock materials are first treated in a gasification reactor to form pyrolysis gases. The pyrolysis gases are then directed into a catalytic reactor for the destruction of residual tars/oils in the gases. Temperatures are maintained within the catalytic reactor at a level sufficient to crack the tars/oils in the gases, while avoiding thermal breakdown of the catalysts. In order to minimize problems associated with the deposition of carbon-containing materials on the catalysts during cracking, a gaseous oxidizing agent preferably consisting of air, oxygen, steam, and/or mixtures thereof is introduced into the catalytic reactor at a high flow rate in a direction perpendicular to the longitudinal axis of the reactor. This oxidizes any carbon deposits on the catalysts, which would normally cause catalyst deactivation.

  19. Preparation and characterization of microparticles of piroxicam by spray drying and spray chilling methods

    PubMed Central

    Dixit, M.; Kini, A.G.; Kulkarni, P.K.

    2010-01-01

    Piroxicam, an anti-inflammatory drug, exhibits poor water solubility and flow properties, poor dissolution and poor wetting. Consequently, the aim of this study was to improve the dissolution of piroxicam. Microparticles containing piroxicam were produced by spray drying, using isopropyl alcohol and water in the ratio of 40:60 v/v as solvent system, and spray chilling technology by melting the drug and chilling it with a pneumatic nozzle to enhance dissolution rate. The prepared formulations were evaluated for in vitro dissolution and solubility. The prepared drug particles were characterized by scanning electron microscopy (SEM), differential scanning calorimeter, X-ray diffraction and Fourier transform infrared spectroscopy. Dissolution profile of the spray dried microparticles was compared with spray-chilled microparticles, pure and recrystallized samples. Spray dried microparticles and spray chilled microparticles exhibited decreased crystallinity and improved micromeritic properties. The dissolution of the spray dried microparticle and spray chilled particles were improved compared with recrystallized and pure sample of piroxicam. Consequently, it was believed that spray drying of piroxicam is a useful tool to improve dissolution but not in case of spray chilling. This may be due to the degradation of drug or variations in the resonance structure or could be due to minor distortion of bond angles. Hence, this spray drying technique can be used for formulation of tablets of piroxicam by direct compression with directly compressible tablet excipients. PMID:21589797

  20. Raman spectroscopy of Cu-Sn-S ternary compound thin films prepared by the low-cost spray-pyrolysis technique.

    PubMed

    Brus, Viktor V; Babichuk, Ivan S; Orletskyi, Ivan G; Maryanchuk, Pavlo D; Yukhymchuk, Volodymyr O; Dzhagan, Volodymyr M; Yanchuk, Igor B; Solovan, Mykhailo M; Babichuk, Iryna V

    2016-04-20

    Cu-Sn-S (CTS) thin films were deposited onto bare and molybdenum (Mo) coated glass substrates by means of the spray pyrolysis technique under different conditions. The CTS thin films obtained are shown, by means of Raman spectroscopy, to consist of two main phases: Cu2SnS3 and Cu3SnS4 as well as of the secondary phase of Cu2-xS. The electrical conductivity of the spray-deposited p-type CTS thin films under investigation is determined by two shallow acceptor levels: Ev+0.07  eV at T<334  K and Ev+0.1  eV at T>334  K. The material of the CTS thin films was established to be a direct-band semiconductor with the bandgap Eg=1.89  eV. The SEM and x-ray energy dispersive analysis show the surface and cross section of the CTS thin film deposited onto molybdenum-coated glass ceramics substrate with the actual atomic ratios of Cu:Sn:S being 2.9:1:2.64, which is in good agreement with the Raman spectra. Also, a small content of residual Cl atoms was found in the CTS thin films under investigation as the by-product of the pyrolytic reactions.

  1. Mercury analysis of various types of coal using acid extraction and pyrolysis methods

    SciTech Connect

    Jae Young Park; Jong Hyun Won; Tai Gyu Lee

    2006-12-15

    The mercury contents of various types of coal currently consumed in Korea were analyzed using acid extraction and pyrolysis methods. The results of analysis by acid extraction and pyrolysis methods were compared and discussed. Generally, high mercury concentrations of 105.6 to 434.5 ng/g (by acid extraction) and 125.7 to 475.4 ng/g (by pyrolysis) were obtained for tested anthracite coals in this study. For bituminous coals, the mercury contents were 11.5-48 ng/g (by acid extraction) and 12.5-52.4 ng/g (by pyrolysis). For coal samples, much simpler and far less time-consuming pyrolysis method tends to give higher values for the Hg concentration than the acid extraction method (by less than 10%) because of the interference from a UV absorption by SOx generated during thermal destruction of coal matrix. Also, further analysis shows that coals with higher densities have higher mercury contents and that the sulfur and mercury contents of coals are positively correlated with each other. 10 refs., 4 figs., 2 tabs.

  2. Influence of impregnation method on metal retention of CCB-treated wood in slow pyrolysis process.

    PubMed

    Kinata, Silao Espérance; Loubar, Khaled; Bouslamti, Amine; Belloncle, Christophe; Tazerout, Mohand

    2012-09-30

    In the present work, the effects of copper, chromium and boron on the pyrolysis of wood and their distribution in the pyrolysis products were investigated. For this, the wood has been impregnated with chromium-copper-boron (CCB). In addition, to describe the effects of impregnation method, vacuum-pressure and dipping methods were also conducted. Thermogravimetric analysis (TGA) results show that an increase in the final residue and decrease in degradation temperature on both methods of treated wood compared to untreated wood. Then, slow pyrolysis experiments were carried out in a laboratory reactor. The mass balance of pyrolysis products is confirmed by TGA. Furthermore, the concentration of metals in the final residue is measured by inductively coupled plasma mass spectroscopy (ICP-MS). The results show that the final residue contains more than 45% of the initial amount of metal present in the treated wood. The phenomenon is more pronounced with vacuum-pressure treated wood. The heating values of pyrolysis products were analyzed. The heating value of charcoal obtained from treated and untreated wood is approximately same. But the heating value of tar from untreated wood is higher than the heating value of the tar from treated wood.

  3. Method and apparatus for atomization and spraying of molten metals

    DOEpatents

    Hobson, D.O.; Alexeff, I.; Sikka, V.K.

    1988-07-19

    A method and device for dispersing molten metal into fine particulate spray, the method comprises applying an electric current through the molten metal and simultaneously applying a magnetic field to the molten metal in a plane perpendicular to the electric current, whereby the molten metal is caused to form into droplets at an angle perpendicular to both the electric current and the magnetic field. The device comprises a structure for providing a molten metal, appropriately arranged electrodes for applying an electric current through the molten metal, and a magnet for providing a magnetic field in a plane perpendicular to the electric current. 11 figs.

  4. CuS p- type thin film characterization deposited on Ti, ITO and glass substrates using spray pyrolysis deposition (SPD) for light emitting diode (LED) application

    NASA Astrophysics Data System (ADS)

    Sabah, Fayroz A.; Ahmed, Naser M.; Hassan, Z.; Rasheed, Hiba S.; Azzez, Shrook A.; Al-Hazim, Nabeel Z.

    2016-07-01

    The copper sulphide (CuS) thin films were grown with good adhesion by spray pyrolysis deposition (SPD) on Ti, ITO and glass substrates at 200 °C. The distance between nozzle and substrate is 30 cm. The composition was prepared by mixing copper chloride CuCl2.2H2O as a source of Cu2+ and sodium thiosulfate Na2S2O3.5H2O as a source of and S2-. Two concentrations (0.2 and 0.4 M) were used for each CuCl2 and Na2S2O3 to be prepared and then sprayed (20 ml). The process was started by spraying the solution for 3 seconds and after 10 seconds the cycle was repeated until the solution was sprayed completely on the hot substrates. The structural characteristics were studied using X-ray diffraction; they showed covellite CuS hexagonal crystal structure for 0.2 M concentration, and covellite CuS hexagonal crystal structure with two small peaks of chalcocite Cu2S hexagonal crystal structure for 0.4 M concentration. Also the surface and electrical characteristics were investigated using Field Emission Scanning Electron Microscopy (FESEM) and current source device, respectively. The surface study for the CuS thin films showed nanorods to be established for 0.2 M concentration and mix of nanorods and nanoplates for 0.4 M concentration. The electrical study showed ohmic behavior and low resistivity for these films. Hall Effect was measured for these thin films, it showed that all samples of CuS are p- type thin films and ensured that the resistivity for thin films of 0.2 M concentration was lower than that of 0.4 M concentration; and for the two concentrations CuS thin film deposited on ITO had the lowest resistivity. This leads to the result that the conductivity was high for CuS thin film deposited on ITO substrate, and the conductivity of the three thin films of 0.2 M concentration was higher than that of 0.4 M concentration.

  5. Analysis of drugs by pyrolysis. I. Selected ion monitoring combined with a pyrolysis method for the determination of carpronium chloride in biological samples.

    PubMed

    Ohya, K; Sano, M

    1977-08-01

    In order to establish an analytical method for carpronium chloride, a parasympathomimetic agent, the pyrolysis reaction of carpronium chloride was examined in a g.c.m.s. system, which revealed that gamma-butyrolactone was produced directly from the drug as the main pyrolysis product. In the case of conversion of [2,2,3,3-2H4]carpronium chloride into the deuterated gamma-butyrolactone, 2H/1H scrambling was observed and confirmed to occur during the pyrolysis process of the deuterated compound. The proportion of gamma-[2H4]butyrolactone among the pyrolysis products was almost independent of the operating conditions, so [2,2,3,3-2H4]carpronium chloride was of practical use as an internal standard for selected ion monitoring. By incorporation of the pyrolysis reaction of carpronium chloride with selected ion monitoring and the use of [2,2,3,3-2H4]carpronium chloride as an internal standard, a rapid, sensitive and selective method was devised for the determination of the drug in biological samples. The method was utilized successfully for the biopharmaceutical studies of carpronium chloride in ma.

  6. Hemostatic powder spray: a new method for managing gastrointestinal bleeding

    PubMed Central

    Papafragkakis, Haris; Ofori, Emmanuel; Ona, Mel A.; Krishnaiah, Mahesh; Duddempudi, Sushil; Anand, Sury

    2015-01-01

    Gastrointestinal bleeding is a leading cause of morbidity and mortality in the United States. The management of gastrointestinal bleeding is often challenging, depending on its location and severity. To date, widely accepted hemostatic treatment options include injection of epinephrine and tissue adhesives such as cyanoacrylate, ablative therapy with contact modalities such as thermal coagulation with heater probe and bipolar hemostatic forceps, noncontact modalities such as photodynamic therapy and argon plasma coagulation, and mechanical hemostasis with band ligation, endoscopic hemoclips, and over-the-scope clips. These approaches, albeit effective in achieving hemostasis, are associated with a 5–10% rebleeding risk. New simple, effective, universal, and safe methods are needed to address some of the challenges posed by the current endoscopic hemostatic techniques. The use of a novel hemostatic powder spray appears to be effective and safe in controlling upper and lower gastrointestinal bleeding. Although initial reports of hemostatic powder spray as an innovative approach to manage gastrointestinal bleeding are promising, further studies are needed to support and confirm its efficacy and safety. The aim of this study was to evaluate the technical feasibility, clinical efficacy, and safety of hemostatic powder spray (Hemospray, Cook Medical, Winston-Salem, North Carolina, USA) as a new method for managing gastrointestinal bleeding. In this review article, we performed an extensive literature search summarizing case reports and case series of Hemospray for the management of gastrointestinal bleeding. Indications, features, technique, deployment, success rate, complications, and limitations are discussed. The combined technical and clinical success rate of Hemospray was 88.5% (207/234) among the human subjects and 81.8% (9/11) among the porcine models studied. Rebleeding occurred within 72 hours post-treatment in 38 patients (38/234; 16.2%) and in three porcine

  7. Colloidal spray method for low cost thin coating deposition

    DOEpatents

    Pham, Ai-Quoc; Glass, Robert S.; Lee, Tae H.

    2002-01-01

    A dense or porous coating of material is deposited onto a substrate by forcing a colloidal suspension through an ultrasonic nebulizer and spraying a fine mist of particles in a carrier medium onto a sufficiently heated substrate. The spraying rate is essentially matched to the evaporation rate of the carrier liquid from the substrate to produce a coating that is uniformly distributed over the surface of the substrate. Following deposition to a sufficient coating thickness, a single sintering step may be used to produce a dense ceramic coating. Using this method, coatings ranging in thickness from about one to several hundred microns can be obtained. By using a plurality of compounds in the colloidal suspension, coatings of mixed composition can be obtained. By using a plurality of solutions and separate pumps and a single or multiple ultrasonic nebulizer(s), and varying the individual pumping rates and/or the concentrations of the solutions, a coating of mixed and discontinuously graded (e.g., stepped) or continuously graded layers may be obtained. This method is particularly useful for depositing ceramic coatings. Dense ceramic coating materials on porous substrates are useful in providing improved electrode performance in devices such as high power density solid oxide fuel cells. Dense ceramic coatings obtained by the invention are also useful for gas turbine blade coatings, sensors, steam electrolyzers, etc. The invention has general use in preparation of systems requiring durable and chemically resistant coatings, or coatings having other specific chemical or physical properties.

  8. Colloidal spray method for low cost thin coating deposition

    DOEpatents

    Pham, Ai-Quoc; Glass, Robert S.; Lee, Tae H.

    2005-01-25

    A dense or porous coating of material is deposited onto a substrate by forcing a colloidal suspension through an ultrasonic nebulizer and spraying a fine mist of particles in a carrier medium onto a sufficiently heated substrate. The spraying rate is essentially matched to the evaporation rate of the carrier liquid from the substrate to produce a coating that is uniformly distributed over the surface of the substrate. Following deposition to a sufficient coating thickness, a single sintering step may be used to produce a dense ceramic coating. Using this method, coatings ranging in thickness from about one to several hundred microns can be obtained. By using a plurality of compounds in the colloidal suspension, coatings of mixed composition can be obtained. By using a plurality of solutions and separate pumps and a single or multiple ultrasonic nebulizer(s), and varying the individual pumping rates and/or the concentrations of the solutions, a coating of mixed and discontinuously graded (e.g., stepped) or continuously graded layers may be obtained. This method is particularly useful for depositing ceramic coatings. Dense ceramic coating materials on porous substrates are useful in providing improved electrode performance in devices such as high power density solid oxide fuel cells. Dense ceramic coatings obtained by the invention are also useful for gas turbine blade coatings, sensors, steam electrolyzers, etc. The invention has general use in preparation of systems requiring durable and chemically resistant coatings, or coatings having other specific chemical or physical properties.

  9. Peculiarities in electrical and optical properties of Cu2Zn1- x Mn x SnS4 films obtained by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Orletskii, I. G.; Mar'yanchuk, P. D.; Solovan, M. N.; Maistruk, E. V.; Kozyarskii, D. P.

    2016-03-01

    Thin films of Cu2Zn1- x Mn x SnS4 (0 ≤ x ≤ 1) solid solutions have been obtained for the first time by the spray pyrolysis of aqueous salt solutions (copper, zinc, manganese, and tin chlorides and thiourea) at a temperature of T S = 563 K. The films possess specific electric conductivities within σ ≈ 35-422 Ω-1 cm-1 and optical bandgap width E g op that increases with the manganese content from 1.54 eV ( x = 0) to 2.25 eV ( x = 1). Electrical and optical properties of the obtained films have been studied and analyzed based on a model of polycrystalline materials with grain boundaries. The energy barriers Eb between grains have been determined. The dependence of the bandgap of Cu2Zn1- x Mn x SnS4 (0 ≤ x ≤ 1) solid solutions on the composition has been established using the results of measurements of the optical transmission and absorption coefficients.

  10. Physical properties of Zn doped TiO2 thin films with spray pyrolysis technique and its effects in antibacterial activity

    NASA Astrophysics Data System (ADS)

    Arunachalam, A.; Dhanapandian, S.; Manoharan, C.; Sivakumar, G.

    2015-03-01

    Zinc doped Titanium dioxide (TiO2: Zn) thin films were deposited onto glass substrates by the spray pyrolysis technique with the substrate temperature 450 °C. The structural, optical, photoluminescence (PL) properties and morphological studies were investigated for the films deposited with various doping concentration (0, 2, 4, 6 and 8 at.%) of zinc. The results of X-ray diffraction (XRD) had shown the presence of anatase peak with a strong orientation along (1 0 1) plane at 8 at.% of Zn-doped TiO2 film. Scanning electron microscopy (SEM) study showed the uniform distribution of grains with porous nature. Atomic force microscopy (AFM) observations indicated the tetragonal shape at 8 at.% of Zn-doped TiO2 with the particle size and decrease in surface roughness. The emission at 398 nm was observed at the 8 at.% of Zn-doped TiO2 thin film. The carrier concentration and Hall mobility was increased with doping. The antibacterial activity was highly yielded for the Zn-doped TiO2 thin films.

  11. Physical properties of Zn doped TiO2 thin films with spray pyrolysis technique and its effects in antibacterial activity.

    PubMed

    Arunachalam, A; Dhanapandian, S; Manoharan, C; Sivakumar, G

    2015-03-05

    Zinc doped Titanium dioxide (TiO2: Zn) thin films were deposited onto glass substrates by the spray pyrolysis technique with the substrate temperature 450°C. The structural, optical, photoluminescence (PL) properties and morphological studies were investigated for the films deposited with various doping concentration (0, 2, 4, 6 and 8at.%) of zinc. The results of X-ray diffraction (XRD) had shown the presence of anatase peak with a strong orientation along (101) plane at 8at.% of Zn-doped TiO2 film. Scanning electron microscopy (SEM) study showed the uniform distribution of grains with porous nature. Atomic force microscopy (AFM) observations indicated the tetragonal shape at 8at.% of Zn-doped TiO2 with the particle size and decrease in surface roughness. The emission at 398nm was observed at the 8at.% of Zn-doped TiO2 thin film. The carrier concentration and Hall mobility was increased with doping. The antibacterial activity was highly yielded for the Zn-doped TiO2 thin films.

  12. Preparation and characterization of Cu2SnS3 ternary semiconductor nanostructures via the spray pyrolysis technique for photovoltaic applications

    NASA Astrophysics Data System (ADS)

    Adelifard, Mehdi; Bagheri Mohagheghi, Mohamad Mehdi; Eshghi, Hosein

    2012-03-01

    Thin films of Cu2SnS3 have been deposited by the spray pyrolysis technique. Various Sn/Cu molar ratios (from 0.0 to 1.0) were applied, which allowed the study of the copper tin sulfide phase. Structural, morphological and compositional analyses have been carried out using x-ray diffraction, field emission scanning electron microscopy and energy dispersive spectroscopy. The pure CuS thin film showed the covellite phase with hexagonal crystal structure, and with increasing the Sn/Cu molar ratio, the films grown were crystallized with triclinic Cu2SnS3 ternary phase. Optical measurement analysis showed that the deposited layers have a relatively high absorption coefficient (~105 cm-1) in the visible spectrum, about one order of magnitude higher than in other published reports. Also these layers presented a reduction of about 1 eV in the values of band gap from 2.57 to 1.58 eV with an increment in the Sn/Cu molar ratio from 0.0 to 1.0. The electrical properties studies showed that all these samples are p-type semiconductors and the resistivity decreases with increasing the Sn/Cu molar ratio.

  13. Effect of Sn doping on the structural, optical and electrical properties of TiO2 films prepared by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Arunachalam, A.; Dhanapandian, S.; Manoharan, C.

    2016-02-01

    In this work, highly oriented pure and Tin-doped Titanium dioxide (Sn-doped TiO2) with porous nature photoelectrodes were deposited on ITO glass plates using spray pyrolysis technique. The XRD pattern revealed the formation of anatase TiO2 with the maximum intensity of (101) plane while doping 6 at% of Sn. The morphological studies depicted the porous nature with the uniform arrangement of small-sized grains. The presence of tin confirmed with the EDX spectra. The size of particles of 13 nm was observed from High Resolution Transmission Electron Microscopy (HR-TEM) analysis. The average transmittance was about 85% for the doped photoelectrode and was observed for the photoelectrode deposited with 6 at% of tin, with decreased energy band gap. The PL study showed the emission peak at 391 nm. The maximum carrier concentration and Hall mobility was observed for the photoelectrode deposited with 6 at% of tin. With these studies, the DSSCs were prepared separately with the dye extracted from Hibiscus Rosasinesis and Hibiscus Surttasinesis and their efficiency was maximum for the DSSC prepared with 6 at% of tin.

  14. Photoelectrochemical performances of n-CdS{sub 1-x}Se{sub x} thin films prepared by spray pyrolysis technique

    SciTech Connect

    Yadav, A.A.; Masumdar, E.U.

    2010-08-15

    The CdS{sub 1-x}Se{sub x} (0.0 {<=} x {<=} 1.0) thin films of various compositions have been deposited onto the amorphous and FTO coated glass substrates using a spray pyrolysis technique. An electrode/electrolyte interface has been formed between an n-type CdS{sub 1-x}Se{sub x} (0.0 {<=} x {<=} 1.0) alloyed/mixed type semiconductor and a sulphide/polysulphide redox electrolyte and investigated through the current-voltage, capacitance-voltage and photovoltaic power output characteristics. The dependence of the dark current through the junction and the junction capacitance on the voltage across the junction have been examined and analysed. Upon illumination of the interface with a light of 20 mW/cm{sup 2}, an open-circuit voltage of the order of 335 mV and a short-circuit current of 1.02 mA/cm{sup 2} have been developed (for x = 0.8), which results in energy conversion efficiency and fill factor 0.79% and 0.46% respectively. The magnitudes of the barrier heights at the interfaces have been determined. The significant electrochemical properties have been observed for a cell with electrode composition x = 0.8. (author)

  15. High power density cell using nanostructured Sr-doped SmCoO3 and Sm-doped CeO2 composite powder synthesized by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Shimada, Hiroyuki; Yamaguchi, Toshiaki; Suzuki, Toshio; Sumi, Hirofumi; Hamamoto, Koichi; Fujishiro, Yoshinobu

    2016-01-01

    High power density solid oxide electrochemical cells were developed using nanostructure-controlled composite powder consisting of Sr-doped SmCoO3 (SSC) and Sm-doped CeO2 (SDC) for electrode material. The SSC-SDC nano-composite powder, which was synthesized by spray pyrolysis, had a narrow particle size distribution (D10, D50, and D90 of 0.59, 0.71, and 0.94 μm, respectively), and individual particles were spherical, composing of nano-size SSC and SDC fragments (approximately 10-15 nm). The application of the powder to a cathode for an anode-supported solid oxide fuel cell (SOFC) realized extremely fine cathode microstructure and excellent cell performance. The anode-supported SOFC with the SSC-SDC cathode achieved maximum power density of 3.65, 2.44, 1.43, and 0.76 W cm-2 at 800, 750, 700, and 650 °C, respectively, using humidified H2 as fuel and air as oxidant. This result could be explained by the extended electrochemically active region in the cathode induced by controlling the structure of the starting powder at the nano-order level.

  16. Effects of Different Salts on Salt-Assisted Ultrasonic Spray Pyrolysis (SA-USP) Calcination for the Synthesis of Strontium Ferrite.

    PubMed

    Hwang, Tea-Yeon; An, Guk-Hwan; Cho, Jeong-Ho; Kim, Jongryoul; Choa, Yong-Ho

    2015-10-01

    Strontium ferrite (hexaferrite), SrFe12O19, was successfully fabricated in sizes ranging from hundreds of nanometers to several micrometers by salt-assisted ultrasonic spray pyrolysis-calcination using different salt media. All samples were single phases of SrFe12O19 without the intermediate phase, α-Fe2O3, and their morphology was hexagonal. As calcination temperature increased, the size of as-calcined samples and saturation magnetization, Ms, increased while coercivity decreased. The particle size of the obtained nanoparticles varied depending on the salt media and calcination temperatures. The best magnetic properties obtained in this experiment were a coercivity of 6973 Oe with a saturation magnetization of 68.3 emu/g. To the best of our knowledge, these coercivity values are the highest ever obtained. We propose a detailed mechanism explaining the growth of these particles and conclude that the resulting single-domain particle size is about 70 nm, taking into account of factors affecting coercivity in ferrite nano- to micro-sized particles.

  17. Spray automated balancing of rotors: Methods and materials

    NASA Technical Reports Server (NTRS)

    Smalley, Anthony J.; Baldwin, Richard M.; Schick, Wilbur R.

    1988-01-01

    The work described consists of two parts. In the first part, a survey is performed to assess the state of the art in rotor balancing technology as it applies to Army gas turbine engines and associated power transmission hardware. The second part evaluates thermal spray processes for balancing weight addition in an automated balancing procedure. The industry survey reveals that: (1) computerized balancing equipment is valuable to reduce errors, improve balance quality, and provide documentation; (2) slow-speed balancing is used exclusively, with no forseeable need for production high-speed balancing; (3) automated procedures are desired; and (4) thermal spray balancing is viewed with cautious optimism whereas laser balancing is viewed with concern for flight propulsion hardware. The FARE method (Fuel/Air Repetitive Explosion) was selected for experimental evaluation of bond strength and fatigue strength. Material combinations tested were tungsten carbide on stainless steel (17-4), Inconel 718 on Inconel 718, and Triballoy 800 on Inconel 718. Bond strengths were entirely adequate for use in balancing. Material combinations have been identified for use in hot and cold sections of an engine, with fatigue strengths equivalent to those for hand-ground materials.

  18. Numerical modeling of spray combustion with an advanced VOF method

    NASA Technical Reports Server (NTRS)

    Chen, Yen-Sen; Shang, Huan-Min; Shih, Ming-Hsin; Liaw, Paul

    1995-01-01

    This paper summarizes the technical development and validation of a multiphase computational fluid dynamics (CFD) numerical method using the volume-of-fluid (VOF) model and a Lagrangian tracking model which can be employed to analyze general multiphase flow problems with free surface mechanism. The gas-liquid interface mass, momentum and energy conservation relationships are modeled by continuum surface mechanisms. A new solution method is developed such that the present VOF model can be applied for all-speed flow regimes. The objectives of the present study are to develop and verify the fractional volume-of-fluid cell partitioning approach into a predictor-corrector algorithm and to demonstrate the effectiveness of the present approach by simulating benchmark problems including laminar impinging jets, shear coaxial jet atomization and shear coaxial spray combustion flows.

  19. Effectiveness of Spray-Based Decontamination Methods for ...

    EPA Pesticide Factsheets

    Report The objective of this project was to assess the effectiveness of spray-based common decontamination methods for inactivating Bacillus (B.) atrophaeus (surrogate for B. anthracis) spores and bacteriophage MS2 (surrogate for foot and mouth disease virus [FMDV]) on selected test surfaces (with or without a model agricultural soil load). Relocation of viable viruses or spores from the contaminated coupon surfaces into aerosol or liquid fractions during the decontamination methods was investigated. This project was conducted to support jointly held missions of the U.S. Department of Homeland Security (DHS) and the U.S. Environmental Protection Agency (EPA). Within the EPA, the project supports the mission of EPA’s Homeland Security Research Program (HSRP) by providing relevant information pertinent to the decontamination of contaminated areas resulting from a biological incident.

  20. Spray pyrolysis deposition of Cu-ZnO and Zn-SnO{sub 2} solar cells

    SciTech Connect

    Khelfane, A.; Tarzalt, H.; Sebboua, B.; Zerrouki, H.; Kesri, N.

    2015-12-31

    Large-gap metal oxides, such as titanium, tin, and zinc oxides, have attracted great interest because of their remarkable potential in dye-sensitized solar cells (DSSC) and their low cost and simple preparation procedure. In this work, we investigated several Zn-SnO{sub 2} and Cu-ZnO thin films that were sprayed under different experimental conditions. We varied [Zn/[Sn] and [Cu/[Zn] ratios, calculated on atomic percent in the starting solution. We report some structural results of the films using X-ray diffraction. Optical reflection and transmission spectra investigated by an UV/VIS/NIR spectrophotometer permit the determination of optical constants. The direct band gap was deduced from the photon energy dependence of the absorption coefficient.

  1. Highly durable superhydrophobic coatings with gradient density by movable spray method

    NASA Astrophysics Data System (ADS)

    Tenjimbayashi, Mizuki; Shiratori, Seimei

    2014-09-01

    Superhydrophobic surface is expected to be applied in anti-fouling, anti-icing, and anti-bacterial. However, practical use is interrupted by low mechanical strength, time-consuming process, and limited coating substrate. Here highly durable superhydrophobic coatings were prepared by simple and novel spraying method, which sprays with changing the "spray distance between substrate and spray" (SD), named "movable spray method." We prepared the solution that changes wettability and durability with spraying distance by mixing SiO2 nanoparticles and ethyl alpha cyanoacrylate polymer (EAC). Then, we evaluated the chemical components and surface morphologies of each spraying distance coatings (0 ˜ 50 cm) by XPS, SEM, and laser scanning microscope. It revealed that surface roughness and SiO2/EAC ratio increased as the SD increases. Thus, durable superhydrophobic coatings were designed by spraying with increasing SD gradually. Glow discharge-optical emission spectrometry analysis revealed that designed coatings showed the gradual increase of SiO2/EAC ratio. As a result, coatings prepared on glass, wood, or aluminum substrates maintained their superhydrophobicity up to the abrasion at 40 kPa. This movable spray method is simple coating by the wet process and prepares robust hydrophobic coating on complex shape and large area substrates. The gradient functional surface was found to have mechanical durability and superhydrophobicity, and wide area applications will be expected.

  2. Deposition of LaMO 3 (M=Co, Cr, Al) films by spray pyrolysis in inductively coupled plasma

    NASA Astrophysics Data System (ADS)

    Ichinose, Hiromichi; Katsuki, Hiroaki; Nagano, Masamitsu

    1994-11-01

    LaMO 3 (M=Co, Cr, Al) films were prepared on substrates by introducing ultrasonically atomized metal nitrate solutions into an inductively coupled plasma under atmospheric pressure (spray-ICP technique). Dense perovskite-type oxide films of LaCoO 3 and LaCrO 3 were obtained at 600-900°C, while the LaAiO 3 films consisted of loosely packed aggregates. Deposition rates of the films were 6-35 nm/min at 600-900°C. The high temperature phases (cubic) of LaCoO 3 and LaAlO 3 crystallized due to effect of grain size. LaCrO 3 film crystallized in the room temperature phase (orthorhombic). LaCoO 3 was highly oriented to (100) on MgO(100), and LaCrO 3 to (011) and (101) on sapphire(001). Lowest electric resistivities of LaCoO 3 and LaCrO 3 film on MgO were 9.8X10 -3 and 2.7X10 -1 Ω m, respectively, at room temperature.

  3. Systems and methods for coating conduit interior surfaces utilizing a thermal spray gun with extension arm

    DOEpatents

    Moore, Karen A.; Zatorski, Raymond A.

    2005-07-12

    Systems and methods for applying a coating to an interior surface of a conduit. In one embodiment, a spray gun configured to apply a coating is attached to an extension arm which may be inserted into the bore of a pipe. The spray gun may be a thermal spray gun adapted to apply a powder coating. An evacuation system may be used to provide a volume area of reduced air pressure for drawing overspray out of the pipe interior during coating. The extension arm as well as the spray gun may be cooled to maintain a consistent temperature in the system, allowing for more consistent coating.

  4. Methods for coating conduit interior surfaces utilizing a thermal spray gun with extension arm

    DOEpatents

    Moore, Karen A.; Zatorski, Raymond A.

    2007-10-02

    Systems and methods for applying a coating to an interior surface of a conduit. In one embodiment, a spray gun configured to apply a coating is attached to an extension arm which may be inserted into the bore of a pipe. The spray gun may be a thermal spray gun adapted to apply a powder coating. An evacuation system may be used to provide a volume area of reduced air pressure for drawing overspray out of the pipe interior during coating. The extension arm as well as the spray gun may be cooled to maintain a consistent temperature in the system, allowing for more consistent coating.

  5. Characterization of a Heterostructure TiO2/SnO2:F/SUBSTRATE with Two Different Geometries, Prepared by Spray Pyrolysis to BE Used as Photocatalyst

    NASA Astrophysics Data System (ADS)

    Velázquez-Cruz, E. I.; Anaya-Castillejos, K. M.; Martínez-Martínez, R.; Soto-Guzmán, A. B.; Falcony, C.

    2013-07-01

    Two TiO2/SnO2:F/substrate hetero-structures (HS) with different geometry were deposited by spray pyrolysis. The thickness for the TiO2 and SnO2:F films was 3.8 μm and 2.3 μm, and the band gap energy 3.3 eV and 3.6 eV, respectively. Both films have a transmittance greater than 70% in most of the visible spectrum. The electrical resistivity of the SnO2:F film was ρ = (1.7)×10-4Ω ṡ cm. The surface morphology of the TiO2 film shows hemispheric agglomerates formed by nano-metric needle/platy shaped particles that give them a porous texture much like a "ball of wool," the length of the needles is from 100 nm and its thickness close to 20 nm. The geometry of HS has an important influence on its efficiency as photocatalyst under low-powered UV radiation. One of the geometry for this HS, in which the TiO2/SnO2:F interface is exposed, showed greater efficiency than the TiO2 and SnO2:F films separately, or than the common "sandwich" type HS geometry. Specifically, a decrease by 62% of the initial concentration of a watery solution of methylene blue (mb) of 20 ppm in approximately 5 h of UV radiation is observed for the exposed interface HS compared with less than 30% reduction observed for the common sandwich type HS.

  6. Comparative studies of CdS, CdS:Al, CdS:Na and CdS:(Al-Na) thin films prepared by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Yılmaz, S.; Atasoy, Y.; Tomakin, M.; Bacaksız, E.

    2015-12-01

    In the present study, the spray pyrolysis technique was used to prepare pure CdS, 4 at.% Al-doped CdS, 4 at.% Na-doped CdS and (4 at.% Al, 4 at.% Na)-co-doped CdS thin films. It was found from X-ray diffraction data that all the specimens showed hexagonal wurtzite structure with the preferred orientation of (101). Scanning electron microscopy results indicated that 4 at.% Al-doping caused a grain growth in the morphology of CdS thin films whereas the 4 at.% Na-doping and (4 at.% Al, 4 at.% Na)-co-doping led to porous structure with small grains. The band gap value of CdS thin films increased to 2.42 eV after 4 at.% Al-doping. However, it reduced to 2.30 eV and 2.08 eV for 4 at.% Na-doping and (4 at.% Al, 4 at.% Na)-co-doping, respectively. The room temperature photoluminescence measurements illustrated that the peak intensity of CdS thin films enhanced with 4 at.% Al-doping while 4 at.% Na-doping and (4 at.% Al, 4 at.% Na)-co-doping caused a decline in the intensity. The maximum carrier concentration and minimum resistivity were obtained for 4 at.% Al-doped CdS thin films, which is associated with the grain growth. Furthermore, (4 at.% Al, 4 at.% Na)-co-doping gave rise to a slight reduction in the carrier concentration and a slight increment in the resistivity. As a result, it can be said that 4 at.% Al-doped CdS thin films exhibited the best electrical and optical properties, which is important for the opto-electronic applications.

  7. Facile synthesis of antimony-doped tin oxide nanoparticles by a polymer-pyrolysis method

    SciTech Connect

    Li, Yuan-Qing; Wang, Jian-Lei; Fu, Shao-Yun; Mei, Shi-Gang; Zhang, Jian-Min; Yong, Kang

    2010-06-15

    In this article, antimony-doped tin oxide (ATO) nanoparticles was synthesized by a facile polymer-pyrolysis method. The pyrolysis behaviors of the polymer precursors prepared via in situ polymerization of metal salts and acrylic acid were analyzed by simultaneous thermogravimetric and differential scanning calorimetry (TG-DSC). The structural and morphological characteristics of the products were studied by powder X-ray diffraction (XRD) and transmission electron microscope (TEM). The results reveal that the ATO nanoparticles calcined at 600 {sup o}C show good crystallinity with the cassiterite structure and cubic-spherical like morphology. The average particle size of ATO decreases from 200 to 15 nm as the Sb doping content increases from 5 mol% to 15 mol%. Electrical resistivity measurement shows that the resistivity for the 10-13 mol% Sb-doped SnO{sub 2} nanoparticles is reduced by more than three orders compared with the pure SnO{sub 2} nanoparticles. In addition, due to its versatility this polymer-pyrolysis method can be extended to facile synthesis of other doped n-type semiconductor, such as In, Ga, Al doped ZnO, Sn doped In{sub 2}O{sub 3}.

  8. Molecular characterization and comparison of shale oils generated by different pyrolysis methods

    USGS Publications Warehouse

    Birdwell, Justin E.; Jin, Jang Mi; Kim, Sunghwan

    2012-01-01

    Shale oils generated using different laboratory pyrolysis methods have been studied using standard oil characterization methods as well as Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) with electrospray ionization (ESI) and atmospheric photoionization (APPI) to assess differences in molecular composition. The pyrolysis oils were generated from samples of the Mahogany zone oil shale of the Eocene Green River Formation collected from outcrops in the Piceance Basin, Colorado, using three pyrolysis systems under conditions relevant to surface and in situ retorting approaches. Significant variations were observed in the shale oils, particularly the degree of conjugation of the constituent molecules and the distribution of nitrogen-containing compound classes. Comparison of FT-ICR MS results to other oil characteristics, such as specific gravity; saturate, aromatic, resin, asphaltene (SARA) distribution; and carbon number distribution determined by gas chromatography, indicated correspondence between higher average double bond equivalence (DBE) values and increasing asphaltene content. The results show that, based on the shale oil DBE distributions, highly conjugated species are enriched in samples produced under low pressure, high temperature conditions, and under high pressure, moderate temperature conditions in the presence of water. We also report, for the first time in any petroleum-like substance, the presence of N4 class compounds based on FT-ICR MS data. Using double bond equivalence and carbon number distributions, structures for the N4 class and other nitrogen-containing compounds are proposed.

  9. Spray vaccination: a method for the immunization of fish

    USGS Publications Warehouse

    Gould, R.W.; O'Leary, P. J.; Garrison, R. L.; Rohovec, J.S.; Fryer, J.L.

    1978-01-01

    The use of immunizing agents is emerging as a complement to other methods of disease control and has been used successfully both experimentally and commercially (FRYER et al., 1977). Two problems exist in the development of fish vaccines: first, to provide efficacious preparations; and second, to provide economic methods for mass vaccination. Vaccines for fish have been delivered by several methods to include: parenteral injection; orally, through incorporation of vaccines into the animal's diet; hyperosmotic infiltration, by placing fish in a hyperosmotic solution followed by a vaccine bath; direct immersion into vaccine suspensions; or by direct addition of vaccine to water in which fish are held (CORBEL, 1975; AMEND, 1976; AMEND and FENDER, 1976; SCHACTE, 1976; ANTIPA and AMEND, 1977; CROY and AMEND, 1977; FRYER, et al., 1977). Each of these techniques has its inherent advantages and disadvantages. Although intraperitoneal injection appears to be most effective, this method is time consuming and stresses the fish being vaccinated. Oral administration is perhaps the most desirable method of vaccine delivery, but in some cases has not provided high levels of resistance (GUNNELS, et al., 1976). Hyperosmotic infil tration and direct immersion are used to vac cinate small fish but may not be economical with larger animals. Addition of vaccine to water has been used experimentally only with an attenuated viral vaccine (FRYER et al., 1976). This report describes another method for mass immunization of fish. A bacterin against Vibrio anguillarum was administered by spraying fish with antigens prepared by selected methods. This technique provided a fast efficacious means of administering vibrio bacterin. 

  10. Microstructural, optical and electrical investigations of Sb-SnO{sub 2} thin films deposited by spray pyrolysis

    SciTech Connect

    Gupta, Sushant; Yadav, B.C.; Dwivedi, Prabhat K.; Das, B.

    2013-09-01

    Highlights: • We controlled structural, morphological, electrical, optical and physical (such as band gap energy) properties by altering the Sb doping concentration. • Variation in bandgap with Sb concentration is in agreement with the Burstein–Moss hypothesis and this hypothesis was further confirmed by plotting E{sub g} vs n{sup 2/3}. • The resistivity and mobility are in the range of 1.512–6.624 × 10{sup −3} Ω cm and 9.75–22.96 cm{sup 2} V{sup −1} s{sup −1}. The e-density lies between 4.11 × 10{sup 19} and 4.24 × 10{sup 20} cm{sup −3}. • We observed that Sb substitution in SnO{sub 2} lattice decreases the crystallite size and the possible reason for this is the creation of Sb monolayer on the surface of SnO{sub 2} crystallite. - Abstract: The structural, optical and electrical properties of spray deposited antimony (Sb) doped tin oxide (SnO{sub 2}) thin films, prepared from SnCl{sub 4} precursor, have been studied as a function of antimony doping concentration. The doping concentration was varied from 0 to 1.5 wt.% of Sb. The analysis of X-ray diffraction patterns revealed that the as deposited doped and undoped tin oxide thin films are pure crystalline tetragonal rutile phase of tin oxide which belongs to the space group P4{sub 2}/mnm (number 136). The surface morphological examination with field emission scanning electron microscopy (FESEM) revealed the fact that the grains are closely packed and pores/voids between the grains are very few. The resistivity (ρ) and mobility (μ) are in the range of 1.512 × 10{sup −3}–6.624 × 10{sup −3} Ω cm and 9.75–22.96 cm{sup 2} V{sup −1} s{sup −1}. The electron density lies between 4.11 × 10{sup 19} and 4.24 × 10{sup 20} cm{sup −3}. A thorough electrical investigation reveals that the film's resistivity depends on carrier concentration. It is found that ionized impurity scattering is the dominant mechanism, which limits the mobility of the carriers. The transmittance spectra for

  11. Method and apparatus for pyrolysis of atactic polypropylene

    DOEpatents

    Staffin, H.K.; Roaper, R.B.

    1986-09-23

    This invention relates to an apparatus and a method for pyrolytic decomposition of polymeric materials into lower molecular weight products involving the heat treatment of raw polymeric material within reactive conduits submerged in a fluidized bed furnace operated at pyrolyzing temperatures. 1 fig.

  12. Method and apparatus for pyrolysis of atactic polypropylene

    DOEpatents

    Staffin, H. Kenneth; Roaper, R. B.

    1986-09-23

    This invention relates to an apparatus and a method for pyrolytic decomposition of polymeric materials into lower molecular weight products involving the heat treatment of raw polymeric material within reactive conduits submerged in a fluidized bed furnace operated at pyrolizing temperatures.

  13. Effects of Concentration and Substrate Type on Structure and Conductivity of p-Type CuS Thin Films Grown by Spray Pyrolysis Deposition

    NASA Astrophysics Data System (ADS)

    Sabah, Fayroz A.; Ahmed, Naser M.; Hassan, Z.

    2017-01-01

    Copper sulphide (CuS) thin films were grown upon Ti, indium tin oxide (ITO), and glass substrates by using spray pyrolysis deposition at 200°C. The films exhibited good adhesion compared to chemical bath deposition. CuCl2·2H2O and Na2S2O3·5H2O precursors were used as Cu2+ and S2- sources, respectively. Two concentrations (i.e., 0.2 M and 0.4 M) were selected in this study. X-ray diffraction analysis reveals that the films with 0.2 M showed only the formation of a covellite CuS phase having a hexagonal crystal structure with diffraction peaks of low intensity. For 0.4 M concentration, in addition to the covellite CuS phase, chalcocite Cu2S phase having a hexagonal crystal structure also appeared with relatively higher intensity peaks for all thin films. Field-emission scanning electron microscopy observations showed the formation of small grains for 0.2 M, whereas a mixture of grains with square-like shape and nanoplates were formed for 0.4 M. Depending on the 0.2 M and 0.4 M thin films thicknesses (3.2 μm and 4 μm, respectively), the band gap energy was obtained from optical measurements to be approximately 2.64 eV for 0.2 M (pure CuS phase), which slightly decreased up to 2.56 eV for 0.4 M concentration. Hall effect measurements showed that all grown films are p-type. The 0.2 M film exhibited much lower sheet resistance ( R sh = 33.96 Ω/Sq-55.70 Ω/Sq) compared to 0.4 M film ( R sh = 104.33 Ω/Sq-466.6 Ω/Sq). Moreover, for both concentrations, the films deposited onto ITO substrate showed the lowest sheet resistance ( R sh = 33.96 Ω/Sq-104.33 Ω/Sq).

  14. Apparatus for Spraying Thin Films by the Flash Evaporation Method,

    DTIC Science & Technology

    The article describes a flash evaporation apparatus used for coating materials with compounds and alloys. The apparatus is simple and easy to produce and can be mounted in a conventional vacuum apparatus. The operation of this apparatus was tested during the spraying of the InSb thin films .

  15. Compensation method for attenuated planar laser images of optically dense sprays

    NASA Astrophysics Data System (ADS)

    Abu-Gharbieh, Rafeef; Persson, John L.; Försth, Michael; Rosén, Arne; Karlström, Anders; Gustavsson, Tomas

    2000-03-01

    We present a method for compensating laser attenuation in optically dense sprays, in particular for use in combustion engine research. Images of the fuel sprays are produced by planar laser imaging, where Mie scattered light from a cross section of the spray is imaged onto a CCD camera. The compensation scheme is based on the Beer Lambert law, which is used here to sum up the loss of light along the path of the laser in the image, and to compensate iteratively, pixel by pixel, for this loss.

  16. Investigating pyrolysis/incineration as a method of resource recovery from solid waste

    NASA Technical Reports Server (NTRS)

    Robertson, Bobby J.; Lemay, Christopher S.

    1993-01-01

    Pyrolysis/incineration (P/I) is a physicochemical method for the generation of recoverable resources from solid waste materials such as inedible plant biomass (IPB), paper, plastics, cardboard, etc. P/I permits the collection of numerous gases with a minimal amount of solid residue. Pyrolysis, also known as starved air incineration, is usually conducted at relatively high temperatures (greater than 500 deg C) in the absence of oxygen. Incineration is conducted at lower temperatures in the presence of oxygen. The primary purpose of this study was to design, construct, and test a model P/I. The system design includes safety requirements for temperature and pressure. The objectives of this study were: (1) to design and construct a P/I system for incorporation with the Hybrid Regenerative Water Recovery System; (2) to initiate testing of the P/I system; (3) to collect and analyze P/I system data; (4) to consider test variables; and (5) to determine the feasibility of P/I as an effective method of resource recovery. A P/I system for the recovery of reuseable resources from solid waste materials was designed, constructed, and tested. Since a large amount of inedible plant biomass (IPB) will be generated in a space-based habitat on the lunar surface and Mars, IPB was the primary waste material tested in the system. Analysis of the effluent gases was performed to determine which gases could be used in a life support system.

  17. Optimization of Plasma Spray Process Using Statistical Methods

    NASA Astrophysics Data System (ADS)

    Gao, F.; Huang, X.; Liu, R.; Yang, Q.

    2012-01-01

    The microstructure features of coatings produced by a plasma spray process are affected significantly by the process parameters such as powder size, spray gun nozzle size, total plasma gas flow, ratio of H2 + N2 over total gas flow, and so on. This article presents a study of the effects of these parameters on the microstructure (porosity, formation of crack, unmelted particle and oxide phase) of NiCrAlY coatings deposited by the Mettech Axial III™ System. A Taguchi array is used to design the spraying process parameters. The results of the microstructure evaluation are used to generate regression equations for the prediction of coating microstructure based on process parameters. The results predicted from the regression equations are in good agreement with the experimental results according to a confidence level of 0.95. Among the parameters examined, the powder size and the ratio of H2 + N2 over total gas flow rate are the most significant parameters affecting the occurrence of crack, porosity, unmelted particle and oxide. Within the range of the designed process parameters, lower powder size and higher ratio of H2 + N2 over total gas flow rate lead to less cracks, pores, unmelted particles but more oxides. Nozzle size has marginal influence on oxides which increase with nozzle size. Gas flow rate has no direct influence on any coating feature evaluated with the range of variation.

  18. Fabrication of polyacrylate core-shell nanoparticles via spray drying method

    NASA Astrophysics Data System (ADS)

    Chen, Pengpeng; Cheng, Zenghui; Chu, Fuxiang; Xu, Yuzhi; Wang, Chunpeng

    2016-05-01

    Fine polyacrylate particles are thought to be environmental plastisols for car industry. However, these particles are mainly dried through demulsification of the latexes, which is not reproducible and hard to be scaled up. In this work, a spray drying method had been applied to the plastisols-used acrylate latex. By adjusting the core/shell ratio, spray drying process of the latex was fully studied. Scanning electronic microscopy observation of the nanoparticles before and after spray drying indicated that the core-shell structures could be well preserved and particles were well separated by spray drying if the shell was thick enough. Otherwise, the particles fused into each other and core-shell structures were destroyed. Polyacrylate plastisols were developed using diisononylphthalate as a plasticizer, and plastigels were obtained after heat treatment of the sols. Results showed that the shell thickness also had a great influence on the storage stability of the plastisols and mechanical properties of the plastigels.

  19. Characterization of carbon silica hybrid fillers obtained by pyrolysis of waste green tires by the STEM–EDX method

    SciTech Connect

    Al-Hartomy, Omar A.; Al-Ghamdi, Ahmed A.; Al Said, Said A. Farha; Dishovsky, Nikolay; Ward, Michael B.; Mihaylov, Mihail; Ivanov, Milcho

    2015-03-15

    Dual phase carbon–silica hybrid fillers obtained by pyrolysis-cum-water vapor of waste green tires have been characterized by energy dispersive X-ray spectroscopy in a scanning transmission electron microscope, silicate analysis, weight analysis, atomic absorption spectroscopy and by inductively coupled plasma–optical emission spectroscopy. The results achieved have shown that the location and distribution of the phases in the carbon silica hybrid fillers as well as their most essential characteristics are influenced by the pyrolysis conditions. The carbon phase of the filler thus obtained is located predominantly in the space among silica aggregates which have already been existing while it has been formed by elastomer destruction in the course of pyrolysis. The presence of ZnS also has been found in the hybrid fillers investigated. - Highlights: • Dual phase fillers obtained by pyrolysis of waste green tires have been characterized. • The STEM–EDX method was used for characterization. • The phase distributions in the fillers are influenced by the pyrolysis conditions.

  20. Genetic programming:  a novel method for the quantitative analysis of pyrolysis mass spectral data.

    PubMed

    Gilbert, R J; Goodacre, R; Woodward, A M; Kell, D B

    1997-11-01

    A technique for the analysis of multivariate data by genetic programming (GP) is described, with particular reference to the quantitative analysis of orange juice adulteration data collected by pyrolysis mass spectrometry (PyMS). The dimensionality of the input space was reduced by ranking variables according to product moment correlation or mutual information with the outputs. The GP technique as described gives predictive errors equivalent to, if not better than, more widespread methods such as partial least squares and artificial neural networks but additionally can provide a means for easing the interpretation of the correlation between input and output variables. The described application demonstrates that by using the GP method for analyzing PyMS data the adulteration of orange juice with 10% sucrose solution can be quantified reliably over a 0-20% range with an RMS error in the estimate of ∼1%.

  1. Antibody immobilization using pneumatic spray: comparison with the avidin-biotin bridge immobilization method.

    PubMed

    Figueroa, Jhon; Magaña, Sonia; Lim, Daniel V; Schlaf, Rudy

    2012-12-14

    The formation of a thin antibody film on a glass surface using pneumatic spray was investigated as a potential immobilization technique for capturing pathogenic targets. Goat-Escherichia coli O157:H7 IgG films were made by pneumatic spray and compared against the avidin-biotin bridge immobilized films by assaying with green fluorescent protein (GFP) transformed E. coli O157:H7 cells and fluorescent reporter antibodies. Functionality, stability, and immobilization of the films were tested. The pneumatic spray films had lower fluorescence intensity values than the avidin-biotin bridge films but resulted in similar detection for E. coli O157:H7 at 10(5)-10(7)cells/ml sample concentrations with no detection of non-E. coli O157:H7 strains. Both methods also resulted in similar percent capture efficiencies. The results demonstrated that immobilization of antibody via pneumatic spray did not render the antibody non-functional and produced stable antibody films. The amount of time necessary for immobilization of the antibody was reduced significantly from 24h for the avidin-biotin bridge to 7 min using the pneumatic spray technique, with additional benefits of greatly reduced use of materials and chemicals. The pneumatic spray technique promises to be an alternative for the immobilization of antibodies on glass slides for capturing pathogenic targets and use in biosensor type devices.

  2. Monte Carlo Method for Predicting a Physically Based Drop Size Distribution Evolution of a Spray

    NASA Astrophysics Data System (ADS)

    Tembely, Moussa; Lécot, Christian; Soucemarianadin, Arthur

    2010-03-01

    We report in this paper a method for predicting the evolution of a physically based drop size distribution of a spray, by coupling the Maximum Entropy Formalism and the Monte Carlo scheme. Using the discrete or continuous population balance equation, a Mass Flow Algorithm is formulated taking into account interactions between droplets via coalescence. After deriving a kernel for coalescence, we solve the time dependent drop size distribution equation using a Monte Carlo method. We apply the method to the spray of a new print-head known as a Spray On Demand (SOD) device; the process exploits ultrasonic spray generation via a Faraday instability where the fluid/structure interaction causing the instability is described by a modified Hamilton's principle. This has led to a physically-based approach for predicting the initial drop size distribution within the framework of the Maximum Entropy Formalism (MEF): a three-parameter generalized Gamma distribution is chosen by using conservation of mass and energy. The calculation of the drop size distribution evolution by Monte Carlo method shows the effect of spray droplets coalescence both on the number-based or volume-based drop size distributions.

  3. The feasibility study of hot cell decontamination by the PFC spray method

    SciTech Connect

    Hui-Jun Won; Chong-Hun Jung; Jei-Kwon Moon

    2008-01-15

    The characteristics of per-fluorocarbon compounds (PFC) are colorless, non-toxic, easily vaporized and nonflammable. Also, some of them are liquids of a high density, low surface tension, low latent heat and low specific heat. These particular chemical and physical properties of fluoro-organic compounds permit their use in very different fields such as electronics, medicine, tribology, nuclear and material science. The Sonatol process was developed under a contract with the DOE. The Sonatol process uses an ultrasonic agitation in a PFC solution that contains a fluorinated surfactant to remove radioactive particles from surfaces. Filtering the suspended particles allows the solutions to be reused indefinitely. They applied the Sonatol process to the decontamination of a heterogeneous legacy Pu-238 waste that exhibited an excessive hydrogen gas generation, which prevents a transportation of such a waste to a Waste Isolation Pilot Plant. Korea Atomic Energy Research Institute (KAERI) is developing dry decontamination technologies applicable to a decontamination of a highly radioactive area loosely contaminated with radioactive particles. This contamination has occurred as a result of an examination of a post-irradiated material or the development of the DUPIC process. The dry decontamination technologies developed are the carbon dioxide pellet spray method and the PFC spray method. As a part of the project, PFC ultrasonic decontamination technology was developed in 2004. The PFC spray decontamination method which is based on the test results of the PFC ultrasonic method has been under development since 2005. The developed PFC spray decontamination equipment consists of four modules (spray, collection, filtration and distillation). Vacuum cup of the collection module gathers the contaminated PFC solution, then the solution is moved to the filtration module and it is recycled. After a multiple recycling of the spent PFC solution, it is purified in the distillation

  4. Study of the influence of substrate temperature on structural, optical, and electrical properties of Zn-doped MnIn2S4 thin films prepared by chemical spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Kennedy, A.; Viswanathan, K.; Pradeev raj, K.

    2016-08-01

    The Zn-doped MnIn2S4 thin films were deposited by chemical spray pyrolysis technique on a heated glass substrate using the aqueous solution of MnCl2, InCl3, (NH2)2CS and ZnCl2. The thin films were grown at different substrate temperatures ranging from 250-400 °C. The synthesized films were characterized by X-ray diffraction (XRD), energy dispersive analysis spectrum (EDS), field emission scanning electron microscope (FESEM), UV-Vis absorption spectroscopy and four probe method. The XRD analysis indicates Zn-doped MnIn2S4 thin films were polycrystalline in nature with a cubic spinel structure having (101) plane as the preferred orientation. The structural parameters like crystalline size (D), dislocation density (δ), strain (ε) and lattice distortion (LD) have been evaluated from XRD results. The energy dispersive analysis spectrum (EDS) predicts the presence of Mn, In, S and Zn in the film grown at 250 °C. The formation of the needle and spherical shaped grains was clearly observed from FE-SEM analysis. From the optical studies, it is analyzed that about (88%) of light transmission occurs in the Vis-IR regions. It is interesting to note that the structural homogeneity and crystallinity of the films has improved due to the decrease in the absorption coefficient (α) and extinction coefficient (K) with an increase in substrate temperature. The calculated optical band gap energies increase (1.51-1.74 eV) with an increase of substrate temperatures. The photoluminescence (PL) spectrum reveals the presence of well-defined band edge (<400 nm) and defect emissions in the wavelength region around 400-650 nm. Moreover, from electrical studies, the electrical resistivity decreases with increase in substrate temperature and a minimum electrical resistivity of 1.20 ×103 Ωm was obtained for the film coated at 400 °C. The high absorption coefficient (α) in the order of 104cm-1 and high transmittance (88%) of the films makes them an efficient absorber and a good window

  5. Adhesive and cohesive properties by indentation method of plasma-sprayed hydroxyapatite coatings

    NASA Astrophysics Data System (ADS)

    Mohammadi, Z.; Ziaei-Moayyed, A. A.; Mesgar, A. Sheikh-Mehdi

    2007-03-01

    Adhesive and cohesive properties of the plasma-sprayed hydroxyapatite (HA) coatings, deposited on Ti-6Al-4V substrates by varying the plasma power level and spray distance (SD), were evaluated by an indentation method. The crystallinity and the porosity decreased with increasing both of these two parameters. The microhardness value, Young's modulus ( E) and coating fracture toughness ( KC) were found to increase with a combinational increase in spray power and SD. The Knoop and Vickers indentation methods were used to estimate E and KC, respectively. The critical point at which no crack appears at the interface was determined by the interface indentation test. This was used to define the apparent interfacial toughness ( KCa) which is representative of the crack initiation resistance of the interface. It was found that KCa reaches to a maximum at a medium increase in both spray power and SD, while other mechanical properties of the coatings reaches to the highest value with further increase in these two plasma parameters. The tensile adhesion strength of the coatings, measure by the standard adhesion test, ISO 13779-4, was shown to alter in the same manner with KCa results. It was deduced that a combinational increase in spray power and SD which leads to a higher mechanical properties in the coatings, does not necessarily tends to a better mechanical properties at the interface.

  6. Spray cooling simulation implementing time scale analysis and the Monte Carlo method

    NASA Astrophysics Data System (ADS)

    Kreitzer, Paul Joseph

    Spray cooling research is advancing the field of heat transfer and heat rejection in high power electronics. Smaller and more capable electronics packages are producing higher amounts of waste heat, along with smaller external surface areas, and the use of active cooling is becoming a necessity. Spray cooling has shown extremely high levels of heat rejection, of up to 1000 W/cm 2 using water. Simulations of spray cooling are becoming more realistic, but this comes at a price. A previous researcher has used CFD to successfully model a single 3D droplet impact into a liquid film using the level set method. However, the complicated multiphysics occurring during spray impingement and surface interactions increases computation time to more than 30 days. Parallel processing on a 32 processor system has reduced this time tremendously, but still requires more than a day. The present work uses experimental and computational results in addition to numerical correlations representing the physics occurring on a heated impingement surface. The current model represents the spray behavior of a Spraying Systems FullJet 1/8-g spray nozzle. Typical spray characteristics are indicated as follows: flow rate of 1.05x10-5 m3/s, normal droplet velocity of 12 m/s, droplet Sauter mean diameter of 48 microm, and heat flux values ranging from approximately 50--100 W/cm2 . This produces non-dimensional numbers of: We 300--1350, Re 750--3500, Oh 0.01--0.025. Numerical and experimental correlations have been identified representing crater formation, splashing, film thickness, droplet size, and spatial flux distributions. A combination of these methods has resulted in a Monte Carlo spray impingement simulation model capable of simulating hundreds of thousands of droplet impingements or approximately one millisecond. A random sequence of droplet impingement locations and diameters is generated, with the proper radial spatial distribution and diameter distribution. Hence the impingement, lifetime

  7. A Method to Predict the Thickness of Poorly-Bonded Material Along Spray and Spray-Layer Boundaries in Cold Spray Deposition

    NASA Astrophysics Data System (ADS)

    Li, Yangfan; Hamada, Yukitaka; Otobe, Katsunori; Ando, Teiichi

    2017-02-01

    Multi-traverse CS provides a unique means for the production of thick coatings and bulk materials from powders. However, the material along spray and spray-layer boundaries is often poorly bonded as it is laid by the leading and trailing peripheries of the spray that carry powder particles with insufficient kinetic energy. For the same reason, the splats in the very first layer deposited on the substrate may not be bonded well either. A mathematical spray model was developed based on an axisymmetric Gaussian mass flow rate distribution and a stepped deposition yield to predict the thickness of such poorly-bonded layers in multi-traverse CS deposition. The predicted thickness of poorly-bonded layers in a multi-traverse Cu coating falls in the range of experimental values. The model also predicts that the material that contains poorly bonded splats could exceed 20% of the total volume of the coating.

  8. A Method to Predict the Thickness of Poorly-Bonded Material Along Spray and Spray-Layer Boundaries in Cold Spray Deposition

    NASA Astrophysics Data System (ADS)

    Li, Yangfan; Hamada, Yukitaka; Otobe, Katsunori; Ando, Teiichi

    2016-12-01

    Multi-traverse CS provides a unique means for the production of thick coatings and bulk materials from powders. However, the material along spray and spray-layer boundaries is often poorly bonded as it is laid by the leading and trailing peripheries of the spray that carry powder particles with insufficient kinetic energy. For the same reason, the splats in the very first layer deposited on the substrate may not be bonded well either. A mathematical spray model was developed based on an axisymmetric Gaussian mass flow rate distribution and a stepped deposition yield to predict the thickness of such poorly-bonded layers in multi-traverse CS deposition. The predicted thickness of poorly-bonded layers in a multi-traverse Cu coating falls in the range of experimental values. The model also predicts that the material that contains poorly bonded splats could exceed 20% of the total volume of the coating.

  9. WC/Ni bronze composite material formation by combined methods of laser cladding and cold spraying

    NASA Astrophysics Data System (ADS)

    Ryashin, N. S.; Malikov, A. G.; Gulyaev, I. P.; Klinkov, S. V.; Kosarev, V. F.; Orishich, A. M.

    2016-10-01

    Formation of composite material containing anti-friction bronze CuAl8.5Fe4Ni5Mn1.5 and reinforced by inner bulk profiled frame of WC/Ni was considered. Combined methods of laser cladding and cold spraying were used. Reinforced cold spraying copper-bronze blend deposits on profiled frames of WC/Ni produced by laser cladding were obtained. Dependence of bronze weight concentration in cold spraying copper-bronze deposit on bronze weight part in powder blend was analyzed. Results of non-contact profiling of reinforcing WC/Ni frame, EDS analysis and microhardness tests of obtained reinforced copper-bronze-WC/Ni composites were presented.

  10. Spray method for recovery of heat-injured Salmonella Typhimurium and Listeria monocytogenes.

    PubMed

    Back, Kyeong-Hwan; Kim, Sang-Oh; Park, Ki-Hwan; Chung, Myung-Sub; Kang, Dong-Hyun

    2012-10-01

    Selective agar is inadequate for supporting recovery of injured cells. During risk assessment of certain foods, both injured and noninjured cells must be enumerated. In this study, a new method (agar spray method) for recovering sublethally heat-injured microorganisms was developed and used for recovery of heat-injured Salmonella Typhimurium and Listeria monocytogenes. Molten selective agar was applied as an overlay to presolidified nonselective tryptic soy agar (TSA) by spray application. Heat-injured cells (55°C for 10 min in 0.1% peptone water or 55°C for 15 min in sterilized skim milk) were inoculated directly onto solidified TSA. After a 2-h incubation period for cell repair, selective agar was applied to the TSA surface with a sprayer, and the plates were incubated. The recovery rate for heat-injured Salmonella Typhimurium and L. monocytogenes with the spray method was compared with the corresponding rates associated with TSA alone, selective media alone, and the conventional overlay method (selective agar poured on top of resuscitated cells grown on TSA and incubated for 2 h). No significant differences (P > 0.05) were found in pathogen recovery obtained with TSA, the overlay method, and the spray method. However, a lower recovery rate (P < 0.05) was obtained for isolation of injured cells on selective media. Overall, these results indicate that the agar spray method is an acceptable alternative to the conventional overlay method and is a simpler and more convenient approach to recovery and detection of injured cells.

  11. One-Dimensional Ablation with Pyrolysis Gas Flow Using a Full Newton's Method and Finite Control Volume Procedure

    NASA Technical Reports Server (NTRS)

    Amar, Adam J.; Blackwell, Ben F.; Edwards, Jack R.

    2007-01-01

    The development and verification of a one-dimensional material thermal response code with ablation is presented. The implicit time integrator, control volume finite element spatial discretization, and Newton's method for nonlinear iteration on the entire system of residual equations have been implemented and verified for the thermochemical ablation of internally decomposing materials. This study is a continuation of the work presented in "One-Dimensional Ablation with Pyrolysis Gas Flow Using a Full Newton's Method and Finite Control Volume Procedure" (AIAA-2006-2910), which described the derivation, implementation, and verification of the constant density solid energy equation terms and boundary conditions. The present study extends the model to decomposing materials including decomposition kinetics, pyrolysis gas flow through the porous char layer, and a mixture (solid and gas) energy equation. Verification results are presented for the thermochemical ablation of a carbon-phenolic ablator which involves the solution of the entire system of governing equations.

  12. Investigation of the spray characteristics for a secondary fuel injection nozzle using a digital image processing method

    NASA Astrophysics Data System (ADS)

    Jeong, Haeyoung; Lee, Kihyung; Ikeda, Yuji

    2007-05-01

    There are many ways to reduce diesel engine exhaust emissions. However, NOx emission is difficult to reduce because the hydrocarbon (HC) concentration in a diesel engine is not sufficient for NOx conversion. Therefore, in order to create stoichiometric conditions in the De-NOx catalyst, a secondary injection system is designed to inject liquid HC into the exhaust pipe. The atomization and distribution characteristics of the HC injected from a secondary injector are key technologies to obtain a high NOx conversion because inhomogeneous droplets of injected HC cause not only high fuel consumption but also deterioration of NOx emission. This paper describes the spray characteristics of a secondary injector including the spray angle, penetration length and breakup behaviour of the spray to optimize the reduction rate of the NOx catalyst. In this study, various optical diagnostics were applied to investigate these spray characteristics, the atomization mechanism and spray developing process. The visualization and image processing method for the spray pulsation were developed by high speed photography. The influence of the fuel supply pressure on the spray behaviour and a more detailed spray developing process have been analysed experimentally using image processing. Finally, the experimental results were used to correlate the spray structure to the injection system performance and to provide a design guide for a secondary injector nozzle.

  13. Method and system including a double rotary kiln pyrolysis or gasification of waste material

    SciTech Connect

    McIntosh, M.J.; Arzoumanidis, G.G.

    1997-09-02

    A method is described for destructively distilling an organic material in particulate form wherein the particulates are introduced through an inlet into one end of an inner rotating kiln ganged to and coaxial with an outer rotating kiln. The inner and outer kilns define a cylindrical annular space with the inlet being positioned in registry with the axis of rotation of the ganged kilns. During operation, the temperature of the wall of the inner rotary kiln at the inlet is not less than about 500 C to heat the particulate material to a temperature in the range of from about 200 C to about 900 C in a pyrolyzing atmosphere to reduce the particulate material as it moves from the one end toward the other end. The reduced particulates including char are transferred to the annular space between the inner and the outer rotating kilns near the other end of the inner rotating kiln and moved longitudinally in the annular space from near the other end toward the one end in the presence of oxygen to combust the char at an elevated temperature to produce a waste material including ash. Also, heat is provided which is transferred to the inner kiln. The waste material including ash leaves the outer rotating kiln near the one end and the pyrolysis vapor leaves through the particulate material inlet. 5 figs.

  14. Method and system including a double rotary kiln pyrolysis or gasification of waste material

    DOEpatents

    McIntosh, Michael J.; Arzoumanidis, Gregory G.

    1997-01-01

    A method of destructively distilling an organic material in particulate form wherein the particulates are introduced through an inlet into one end of an inner rotating kiln ganged to and coaxial with an outer rotating kiln. The inner and outer kilns define a cylindrical annular space with the inlet being positioned in registry with the axis of rotation of the ganged kilns. During operation, the temperature of the wall of the inner rotary kiln at the inlet is not less than about 500.degree. C. to heat the particulate material to a temperature in the range of from about 200.degree. C. to about 900.degree. C. in a pyrolyzing atmosphere to reduce the particulate material as it moves from the one end toward the other end. The reduced particulates including char are transferred to the annular space between the inner and the outer rotating kilns near the other end of the inner rotating kiln and moved longitudinally in the annular space from near the other end toward the one end in the presence of oxygen to combust the char at an elevated temperature to produce a waste material including ash. Also, heat is provided which is transferred to the inner kiln. The waste material including ash leaves the outer rotating kiln near the one end and the pyrolysis vapor leaves through the particulate material inlet.

  15. A method and system including a double rotary kiln pyrolysis or gasification of waste material

    SciTech Connect

    McIntosh, M.J.; Arzoumanidis, G.G.

    1995-12-31

    A method is described for destructively distilling an organic material in particulate form wherein the particulates are introduced through an inlet into one end of an inner rotating kiln ganged to and coaxial with an outer rotating kiln. The inner and outer kilns define a cylindrical annular space with the inlet being positioned in registry with the axis of rotation of the ganged kilns. During operation, the temperature of the wall of the inner rotary kiln at the inlet is not less than about 500 C to heat the particulate material to a temperature in the range of from about 200 C to about 900 C in a pyrolyzing atmosphere to reduce the particulate material as it moves from the one end toward the other end. The reduced particulates including char are transferred to the annular space between the inner and the outer rotating kilns near the other end of the inner rotating kiln and moved longitudinally in the annular space from near the other end toward the one end in the presence of oxygen to combust the char at an elevated temperature to produce a waste material including ash. Also, heat is provided which is transferred to the inner kiln. The waste material including ash leaves the outer rotating kiln near the one end and the pyrolysis vapor leaves through the particulate material inlet.

  16. Syngas production by two-stage method of biomass catalytic pyrolysis and gasification.

    PubMed

    Xie, Qinglong; Kong, Sifang; Liu, Yangsheng; Zeng, Hui

    2012-04-01

    A two-stage technology integrated with biomass catalytic pyrolysis and gasification processes was utilized to produce syngas (H(2)+CO). In the presence of different nickel based catalysts, effects of pyrolysis temperature and gasification temperature on gas production were investigated. Experimental results showed that more syngas and char of high quality could be obtained at a temperature of 750°C in the stage of pyrolysis, and in the stage of gasification, pyrolysis char (produced at 750°C) reacted with steam and the maximum yield of syngas was obtained at 850°C. Syngas yield in this study was greatly increased compared with previous studies, up to 3.29Nm(3)/kg biomass. The pyrolysis process could be well explained by Arrhenius kinetic first-order rate equation. XRD analyses suggested that formation of Mg(0.4)Ni(0.6)O and increase of Ni(0) crystallite size were two main reasons for the deactivation of nickel based catalysts at higher temperature.

  17. Analytical methods to characterize heterogeneous raw material for thermal spray process: cored wire Inconel 625

    NASA Astrophysics Data System (ADS)

    Lindner, T.; Bonebeau, S.; Drehmann, R.; Grund, T.; Pawlowski, L.; Lampke, T.

    2016-03-01

    In wire arc spraying, the raw material needs to exhibit sufficient formability and ductility in order to be processed. By using an electrically conductive, metallic sheath, it is also possible to handle non-conductive and/or brittle materials such as ceramics. In comparison to massive wire, a cored wire has a heterogeneous material distribution. Due to this fact and the complex thermodynamic processes during wire arc spraying, it is very difficult to predict the resulting chemical composition in the coating with sufficient accuracy. An Inconel 625 cored wire was used to investigate this issue. In a comparative study, the analytical results of the raw material were compared to arc sprayed coatings and droplets, which were remelted in an arc furnace under argon atmosphere. Energy-dispersive X-ray spectroscopy (EDX) and X-ray fluorescence (XRF) analysis were used to determine the chemical composition. The phase determination was performed by X-ray diffraction (XRD). The results were related to the manufacturer specifications and evaluated in respect to differences in the chemical composition. The comparison between the feedstock powder, the remelted droplets and the thermally sprayed coatings allows to evaluate the influence of the processing methods on the resulting chemical and phase composition.

  18. Formate-assisted pyrolysis

    DOEpatents

    DeSisto, William Joseph; Wheeler, Marshall Clayton; van Heiningen, Adriaan R. P.

    2015-03-17

    The present invention provides, among other thing, methods for creating significantly deoxygenated bio-oils form biomass including the steps of providing a feedstock, associating the feedstock with an alkali formate to form a treated feedstock, dewatering the treated feedstock, heating the dewatered treated feedstock to form a vapor product, and condensing the vapor product to form a pyrolysis oil, wherein the pyrolysis oil contains less than 30% oxygen by weight.

  19. Extremely fine structured cathode for solid oxide fuel cells using Sr-doped LaMnO3 and Y2O3-stabilized ZrO2 nano-composite powder synthesized by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Shimada, Hiroyuki; Yamaguchi, Toshiaki; Sumi, Hirofumi; Nomura, Katsuhiro; Yamaguchi, Yuki; Fujishiro, Yoshinobu

    2017-02-01

    A solid oxide fuel cell (SOFC) for high power density operation was developed with a microstructure-controlled cathode using a nano-composite powder of Sr-doped LaMnO3 (LSM) and Y2O3-stabilized ZrO2 (YSZ) synthesized by spray pyrolysis. The individual LSM-YSZ nano-composite particles, formed by crystalline and amorphous nano-size LSM and YSZ particles, showed spherical morphology with uniform particle size. The use of this powder for cathode material led to an extremely fine microstructure, in which all the LSM and YSZ grains (approximately 100-200 nm) were highly dispersed and formed their own network structures. This microstructure was due to the two phase electrode structure control using the powder, namely, nano-order level in each particle and micro-order level between particles. An anode-supported SOFC with the LSM-YSZ cathode using humidified H2 as fuel and ambient air as oxidant exhibited high power densities, such as 1.29 W cm-2 under a voltage of 0.75 V and a maximum power density of 2.65 W cm-2 at 800 °C. Also, the SOFC could be stably operated for 250 h with no degradation, even at a high temperature of 800 °C.

  20. Spray pyrolysis of MgO templates on Hastelloy C276 and 310-austenitic stainless steel substrates for Y Ba2Cu3O7 (YBCO) deposition by pulsed laser deposition

    NASA Astrophysics Data System (ADS)

    Khateeb, Shadi Al; Button, T. W.; Abell, J. S.

    2010-09-01

    MgO thin films were deposited on Hastelloy C276 (HC) and 310 austenitic stainless steel by the spray pyrolysis technique, using magnesium nitrate and magnesium acetate as precursors. Thermogravimetrical analysis of the decomposition of the precursors was used to provide a guideline temperature for the thin film deposition. It was suggested that an amorphous MgO thin film was deposited on both 310-stainless steel and Hastelloy C-276 when using low concentration of the magnesium nitrate precursor. Higher concentrations were needed to obtain (200) oriented MgO films on C276. However, 310-stainless steel was found to not be a suitable substrate for MgO thin film deposition due to surface instability. A (200) oriented MgO thin film was grown on Hastelloy C276 using a magnesium acetate precursor at a much lower concentration compared to the nitrate precursor. The characterization of the thin films was done using scanning electron microscopy, x-ray photoelectron spectroscopy, atomic force microscopy, x-ray diffraction 2θ-scans, rocking curves (ω-scans), and pole figure measurements. MgO was found to have a very weak in-plane texture.

  1. Confined-Pyrolysis as an Experimental Method for Hydrothermal Organic Synthesis

    NASA Technical Reports Server (NTRS)

    Leif, Roald N.; Simoneit, Bernd R. T.

    1995-01-01

    A closed pyrolysis system has been developed as a tool for studying the reactions of organic compounds under extreme hydrothermal conditions. Small high pressure stainless steel vessels in which the ratio of sediment or sample to water has been adjusted to eliminate the headspace at peak experimental conditions confines the organic components to the bulk solid matrix and eliminates the partitioning of the organic compounds away from the inorganic components during the experiment. Confined pyrolysis experiments were performed to simulate thermally driven catagenetic changes in sedimentary organic matter using a solids to water ratio of 3.4 to 1. The extent of alteration was measured by monitoring the steroid and triterpenoid biomarkers and polycyclic aromatic hydrocarbon distributions. These pyrolysis experiments duplicated the hydrothermal transformations observed in nature. Molecular probe experiments using alkadienes, alkenes and alkanes in H2O and D2O elucidated the isomerization and hydrogenation reactions of aliphatic and the competing oxidative reactions occurring under hydrothermal conditions. This confined pyrolysis technique is being applied to test experiments on organic synthesis of relevance to chemical evolution for the origin of life.

  2. Methods for detecting the mobility of trace elements during medium-temperature pyrolysis

    USGS Publications Warehouse

    Shiley, R.H.; Konopka, K.L.; Cahill, R.A.; Hinckley, C.C.; Smith, Gerard V.; Twardowska, H.; Saporoschenko, Mykola

    1983-01-01

    The mobility (volatility) of trace elements in coal during pyrolysis has been studied for distances of up to 40 cm between the coal and the trace element collector, which was graphite or a baffled solvent trap. Nineteen elements not previously recorded as mobile were detected. ?? 1983.

  3. Fabrication of ordered bulk heterojunction organic photovoltaic cells using nanopatterning and electrohydrodynamic spray deposition methods.

    PubMed

    Park, Sung-Eun; Kim, Sehwan; Kim, Kangmin; Joe, Hang-Eun; Jung, Buyoung; Kim, Eunkyoung; Kim, Woochul; Min, Byung-Kwon; Hwang, Jungho

    2012-12-21

    Organic photovoltaic cells with an ordered heterojunction (OHJ) active layer are expected to show increased performance. In the study described here, OHJ cells were fabricated using a combination of nanoimprinting and electrohydrodynamic (EHD) spray deposition methods. After an electron donor material was nanoimprinted with a PDMS stamp (valley width: 230 nm, period: 590 nm) duplicated from a Si nanomold, an electron acceptor material was deposited onto the nanoimprinted donor layer using an EHD spray deposition method. The donor-acceptor interface layer was observed by obtaining cross-sectional images with a focused ion beam (FIB) microscope. The photocurrent generation performance of the OHJ cells was evaluated with the current density-voltage curve under air mass (AM) 1.5 conditions. It was found that the surface morphology of the electron acceptor layer affected the current and voltage outputs of the photovoltaic cells. When an electron acceptor layer with a smooth thin (250 nm above the valley of the electron donor layer) surface morphology was obtained, power conversion efficiency was as high as 0.55%. The electrohydrodynamic spray deposition method used to produce OHJ photovoltaic cells provides a means for the adoption of large area, high throughput processes.

  4. The Optical Properties of CdSe Quantum Dots by Using Spray-Atomization Method

    NASA Astrophysics Data System (ADS)

    Rosmani, C. H.; Abdullah, S.; Rusop, M.

    2013-06-01

    Cadmium Selenide (CdSe) quantum dots (QDs) is inorganic material by using spray-atomization method which is the novelty to find out the optical properties for the CdSe QDs. The Selenium (Se) precursor and Cadmium (Cd) precursor were prepared first. Se precursor by using sodium sulfite aqueous was mixed with selenium (Se) powder. For Cd precursor was used cadmium chloride (CdCI) as the Cd precursor. From previous research, CdSe QDs was obtained by using capping agent such as tri-n-octylphosphine oxide (TOPO) and trioctylphosphine (TOP). These capping agent are hazardous to environment and human. By using spray-atomization method it is more safe and economically. The photoluminescence (PL) was used to investigate the optical properties and to investigate the energy band gap from PL result. The field emission scanning electron microscopy (FESEM) was used to know the surface morphology of CdSe QDs. By PL result, the energy band gap was calculate and the comparison was investigate between the size of particle and the energy band gap. This important in this paper is to investigate the optical properties of CdSe QDs by using sprays-atomization method and to relate with the particle size.

  5. Numerical Modeling of Spray Combustion with an Unstructured-Grid Method

    NASA Technical Reports Server (NTRS)

    Shang, H. M.; Chen, Y. S.; Liaw, P.; Shih, M. H.; Wang, T. S.

    1996-01-01

    The present unstructured-grid method follows strictly the basic finite volume forms of the conservation laws of the governing equations for the entire flow domain. High-order spatially accurate formulation has been employed for the numerical solutions of the Navier-Stokes equations. A two-equation k-epsilon turbulence model is also incorporated in the unstructured-grid solver. The convergence of the resulted linear algebraic equation is accelerated with preconditioned Conjugate Gradient method. A statistical spray combustion model has been incorporated into the present unstructured-grid solver. In this model, spray is represented by discrete particles, rather than by continuous distributions. A finite number of computational particles are used to predict a sample of total population of particles. Particle trajectories are integrated using their momentum and motion equations and particles exchange mass, momentum and energy with the gas within the computational cell in which they are located. The interaction calculations are performed simultaneously and eliminate global iteration for the two-phase momentum exchange. A transient spray flame in a high pressure combustion chamber is predicted and then the solution of liquid-fuel combusting flow with a rotating cup atomizer is presented and compared with the experimental data. The major conclusion of this investigation is that the unstructured-grid method can be employed to study very complicated flow fields of turbulent spray combustion. Grid adaptation can be easily achieved in any flow domain such as droplet evaporation and combustion zone. Future applications of the present model can be found in the full three-dimensional study of flow fields of gas turbine and liquid propulsion engine combustion chambers with multi-injectors.

  6. Transparent conductive PVP/AgNWs films for flexible organic light emitting diodes by spraying method

    NASA Astrophysics Data System (ADS)

    Hu, Jun-tao; Mei, Wen-juan; Ye, Kang-li; Wei, Qing-qing; Hu, Sheng

    2016-05-01

    In this study, a simple spraying method is used to prepare the transparent conductive films (TCFs) based on Ag nanowires (AgNWs). Polyvinylpyrrolidone (PVP) is introduced to modify the interface of substrate. The transmittance and bending performance are improved by optimizing the number of spraying times and the solution concentration and controlling the annealing time. The spraying times of 20, the concentration of 2 mg/mL and the annealing time of 10 min are chosen to fabricate the PVP/AgNWs films. The transmittance of PVP/AgNWs films is 53.4%—67.9% at 380—780 nm, and the sheet resistance is 30 Ω/□ which is equivalent to that of commercial indium tin oxide (ITO). During cyclic bending tests to 500 cycles with bending radius of 5 mm, the changes of resistivity are negligible. The performance of PVP/AgNW transparent electrodes has little change after being exposed to the normal environment for 1 000 h. The adhesion to polymeric substrate and the ability to endure bending stress in AgNWs network films are both significantly improved by introducing PVP. Spraying method makes AgNWs form a stratified structure on large-area polymer substrates, and the vacuum annealing method is used to weld the AgNWs together at junctions and substrates, which can improve the electrical conductivity. The experimental results indicate that PVP/AgNW transparent electrodes can be used as transparent conductive electrodes in flexible organic light emitting diodes (OLEDs).

  7. An exploration of the cold gas-dynamic spray method for several materials systems

    SciTech Connect

    McCune, R.C.; Papyrin, A.N.; Hall, J.N.; Riggs, W.L. II; Zajchowski, P.H.

    1995-12-31

    This paper reports activities of a consortium of companies formed under the aegis of the National Center for Manufacturing Sciences (NCMS) to explore a cold gas-dynamic spray method (CGSM) developed in Russia by Alkhimov, Papyrin and coworkers. In this spray process metal powder particles develop into a coating as a result of ballistic impingement on a suitable substrate. In some instances, surface preparation of the substrate using such traditional methods as grit blasting is unnecessary. The spray nozzle used in this process has been designed so as to permit introduction of powder particles into a preheated gas stream which is then rendered supersonic by expansion through a converging-diverging throat, with accompanying temperature reduction. Thus, the temperature of the gas stream is always below the melting point of the particulate material, providing coatings developed primarily from particles in the solid state. The fundamentals of CGSM are reviewed and results from several material combinations explored in the first phase of the research program are presented. Experimental coatings including copper on alumina ceramic, steel on cast aluminum, and a chromium carbide composite on titanium were produced. Typical microstructures, porosity, adhesion, and physical characteristics of these coatings are discussed.

  8. δ18O analysis of individual carbohydrates - a new method for GC-pyrolysis-IRMS

    NASA Astrophysics Data System (ADS)

    Lehmann, Marco M.; Fischer, Maria; Zech, Michael; Siegwolf, Rolf T. W.; Saurer, Matthias

    2015-04-01

    Measuring the oxygen isotopic composition (δ18O) of various plant tissues is a widely used tool to investigate biochemical and physiological processes. While we have a good understanding about the hydrological cycle in plants with an evaporative enrichment in 18O in leaf water, we still lack knowledge about the biochemical link between the oxygen atoms in leaf water, leaf assimilates, and stem cellulose and associated isotope fractionations. Especially, the influence of different environmental factors on δ18O of individual carbohydrates (i.e. sugars) and thus on δ18O of cellulose is not fully resolved. A better understanding of these processes may improve climatic reconstructions of tree-ring studies about past environmental conditions. However, further progress in this topic is limited since a precise and reliable method to determine δ18O of individual sugars has not been available yet. With our new approach we attempt to overcome this issue by establishing a new methylation derivatization method suitable for GC-pyrolysis -IRMS. A methyl group (CH3) was thereby added to all hydroxyl groups of a sugar (e.g., glucose, fructose, and sucrose) during a catalyzed one-pot reaction overnight in acetonitrile with methyl iodide (CH3-I) and silver oxide, making them amenable for GC analysis. First results show a very good precision for δ18O of sucrose, but also δ18O of other high-abundant sugars such as glucose and fructose could be measured for the first time. We successfully analyzed a standard mix of all three sugars and determined various other carbohydrates not only related to plant sciences (e.g. mannitol, lactose), showing promising δ18O results. First tests with real plant samples were performed to make this method available for determining δ18O of individual carbohydrates of diverse plant tissues. In future, this new methylation derivatization method should allow us analyzing plant samples of different field sites and of lab experiments to investigate the

  9. Method and Process Development of Advanced Atmospheric Plasma Spraying for Thermal Barrier Coatings

    NASA Astrophysics Data System (ADS)

    Mihm, Sebastian; Duda, Thomas; Gruner, Heiko; Thomas, Georg; Dzur, Birger

    2012-06-01

    Over the last few years, global economic growth has triggered a dramatic increase in the demand for resources, resulting in steady rise in prices for energy and raw materials. In the gas turbine manufacturing sector, process optimizations of cost-intensive production steps involve a heightened potential of savings and form the basis for securing future competitive advantages in the market. In this context, the atmospheric plasma spraying (APS) process for thermal barrier coatings (TBC) has been optimized. A constraint for the optimization of the APS coating process is the use of the existing coating equipment. Furthermore, the current coating quality and characteristics must not change so as to avoid new qualification and testing. Using experience in APS and empirically gained data, the process optimization plan included the variation of e.g. the plasma gas composition and flow-rate, the electrical power, the arrangement and angle of the powder injectors in relation to the plasma jet, the grain size distribution of the spray powder and the plasma torch movement procedures such as spray distance, offset and iteration. In particular, plasma properties (enthalpy, velocity and temperature), powder injection conditions (injection point, injection speed, grain size and distribution) and the coating lamination (coating pattern and spraying distance) are examined. The optimized process and resulting coating were compared to the current situation using several diagnostic methods. The improved process significantly reduces costs and achieves the requirement of comparable coating quality. Furthermore, a contribution was made towards better comprehension of the APS of ceramics and the definition of a better method for future process developments.

  10. Effect of solvent volume on the physical properties of aluminium doped nanocrystalline zinc oxide thin films deposited using a simplified spray pyrolysis technique

    NASA Astrophysics Data System (ADS)

    Jabena Begum, N.; Mohan, R.; Ravichandran, K.

    2013-01-01

    Aluminium doped zinc oxide (AZO) thin films were deposited by employing a low cost and simplified spray technique using a perfume atomizer from starting solutions having different volumes (10, 20, … , 50 mL) of solvent. The effect of solvent volume on the structural, electrical, optical, photoluminescence (PL) and surface morphological properties was studied. The electrical resistivity of the AZO films is remarkably influenced by the variation in the solvent volume. The X-ray diffraction profiles clearly showed that all the films have preferential orientation along the (0 0 2) plane irrespective of the solvent volume. The crystallite size was found to be in the nano range of 35-46 nm. The optical transmittance in the visible region is desirably high (>85%). The AFM images show columnar morphology with varying grain size. The PL studies revealed that the AZO film deposited from 50 mL of solvent volume has good quality with lesser defect density.

  11. Pyrolysis Gas Flow in Thermally Ablating Media Using Time-Implicit Discontinuous Galerkin Methods

    DTIC Science & Technology

    2011-01-01

    dynamics of flow of pyrolysis gas in a charring ablating media. We have benchmarked our results with the published data. The protective coating of... Dynamics Laboratory and Test Facility,Department of Mechanical and Aerospace Engineering,Gainesville,FL,32611 8. PERFORMING ORGANIZATION REPORT NUMBER 9...Gas flow Code, which is a family of our in-house finite element modules, and has been used to solve problems in plasma dynamics like low pressure

  12. Screening for inhibitors of histone deacetylase by incorporating a spraying method to micro-arrayed compound screening.

    PubMed

    Sabet, R S; Marcotte, P; Glaser, K; Burns, D J; Warrior, U; Groebe, D R

    2004-03-01

    We have developed a method of spraying assay reagents onto a target gel in the Micro-Arrayed Compound Screening ( micro ARCS) format. After application of target gels to compound sheets, subsequent reagents can be applied by spraying onto the target gel. The spraying method conserves on assay reagents by up to 10-fold, eliminates the need for casting additional agarose gels, and increases the throughput of a screen by 3-fold. To demonstrate the efficacy of applying the spraying method to micro ARCS, we screened over 600,000 compounds for inhibitors of histone deacetylase (HDAC). Commercially available HDAC substrate and reaction developer were sprayed directly onto the gel to initiate the reaction and to amplify the signal, respectively. Picks in the primary screen were retested at a density of 384 compounds per sheet in the micro ARCS format. IC(50) values for active compounds were confirmed in a 96-well plate assay. The screen identified several small molecule inhibitors of the enzyme, including members of several classes of known HDAC inhibitors. The combination of the high-density format of micro ARCS, the efficiency of the spraying method, and a timed sequence of adding assay reagents permitted a screening throughput of 200,000 tests an hour. We present the details of the screening format and the analysis of the hits from the screen.

  13. Effect of boric acid on the properties of Li{sub 2}MnO{sub 3}·LiNi{sub 0.5}Mn{sub 0.5}O{sub 2} composite cathode powders prepared by large-scale spray pyrolysis with droplet classifier

    SciTech Connect

    Hong, Young Jun; Choi, Seung Ho; Sim, Chul Min; Lee, Jung-Kul; Kang, Yun Chan

    2012-12-15

    Graphical abstract: Display Omitted Highlights: ► Spherical shape Li{sub 2}MnO{sub 3}·LiNi{sub 0.5}Mn{sub 0.5}O{sub 2} composite cathode powders are prepared by large-scale spray pyrolysis with droplet classifier. ► Boric acid improves the morphological and electrochemical properties of the composite cathode powders. ► The discharge capacity of the composite cathode powders decreases from 217 to 196 mAh g{sup −1} by the 30th cycle. -- Abstract: Spherically shaped 0.3Li{sub 2}MnO{sub 3}·0.7LiNi{sub 0.5}Mn{sub 0.5}O{sub 2} composite cathode powders with filled morphology and narrow size distribution are prepared by large-scale spray pyrolysis. A droplet classification reduces the standard deviation of the size distribution of the composite cathode powders. Addition of boric acid improves the morphological properties of the product powders by forming a lithium borate glass material with low melting temperature. The optimum amount of boric acid dissolved in the spray solution is 0.8 wt% of the composite powders. The powders prepared from the spray solution with 0.8 wt% boric acid have a mixed layered crystal structure comprising Li{sub 2}MnO{sub 3} and LiNi{sub 0.5}Mn{sub 0.5}O{sub 2} phases, thus forming a composite compound. The initial charge and discharge capacities of the composite cathode powders prepared from the 0.8 wt% boric acid spray solution are 297 and 217 mAh g{sup −1}, respectively. The discharge capacity of the powders decreases from 217 to 196 mAh g{sup −1} by the 30th cycle, in which the capacity retention is 90%.

  14. Development of Spray Coating Methods and Materials to Replace Aluminum Cladding of Aging Aircraft for Corrosion Protection

    DTIC Science & Technology

    2007-06-01

    Replace FA9550-06-C-0113 Aluminum Cladding of Aging Aircraft for Corrosion Protection 5b. GRANTNUMBER [AF STTR Phase I Final Technical Report] 5c. PROGRAM...development of glassy coatings is limited by non-availability of aluminum based BMG powder feedstock for spraying. 15. SUBJECT TERMS STTR Report Corrosion ... aluminum cladding of aging aircraft for corrosion protection ABSTRACT The objective of this AF STTR Phase I work was to develop spray coating methods and new

  15. Recent advances in nanoparticle preparation by spray and micro-emulsion methods.

    PubMed

    Eslamian, Morteza; Shekarriz, Marzieh

    2009-01-01

    Micro- and nano-sized metal, semiconductor, pharmaceutical, and simple or complex ceramic particles have numerous applications in the development of sensors, thermal barrier coatings, catalysts, pigments, drugs, etc. The challenges include controlling the particle size, size distribution, particle crystallinity, morphology and shape, being able to use the nanoparticles for a given purpose, and to produce them from a variety of precursors. There are several methods to produce nanoparticles, each suitable for a range of applications. In this article, two methods that are receiving increasing attention are considered: spray and microemulsion methods. Spray techniques are single-step methods of producing a broad spectrum of simple to multicomponent functional micro and nanoparticles and quantum dots. Microemulsion is a wet chemistry method. A micro-emulsion system consists of aqueous domains, called reverse micelles, dispersed in a continuous oil phase. In this article, the above mentioned methods of nanoparticle production are introduced and recent advances, research directions and challenges, and the pertinent patents are reviewed and discussed.

  16. A new formulation for orally disintegrating tablets using a suspension spray-coating method.

    PubMed

    Okuda, Y; Irisawa, Y; Okimoto, K; Osawa, T; Yamashita, S

    2009-12-01

    The aim of this study was to design a new orally disintegrating tablet (ODT) that has high tablet hardness and a fast oral disintegration rate using a new preparation method. To obtain rapid disintegration granules (RDGs), a saccharide, such as trehalose, mannitol, or lactose, was spray-coated with a suspension of corn starch using a fluidized-bed granulator (suspension method). As an additional disintegrant, crospovidone, light anhydrous silicic acid, or hydroxypropyl starch was also included in the suspension. The RDGs obtained possessed extremely large surface areas, narrow particle size distribution, and numerous micro-pores. When tabletting these RDGs, it was found that the RDGs increased tablet hardness by decreasing plastic deformation and increasing the contact frequency between granules. In all tablets, a linear relationship was observed between tablet hardness and oral disintegration time. From each linear correlation line, a slope (D/H value) and an intercept (D/H(0) value) were calculated. Tablets with small D/H and D/H(0) values could disintegrate immediately in the oral cavity regardless of the tablet hardness and were considered to be appropriate for ODTs. Therefore, these values were used as key parameters to select better ODTs. Of all the RDGs prepared in this study, mannitol spray-coated with a suspension of corn starch and crospovidone (2.5:1 w/w ratio) showed most appropriate properties for ODTs; fast in vivo oral disintegration time, and high tablet hardness. In conclusion, this simple method to prepare superior formulations for new ODTs was established by spray-coating mannitol with a suspension of appropriate disintegrants.

  17. Method and Apparatus for Thermal Spraying of Metal Coatings Using Pulsejet Resonant Pulsed Combustion

    NASA Technical Reports Server (NTRS)

    Paxson, Daniel E. (Inventor)

    2014-01-01

    An apparatus and method for thermal spraying a metal coating on a substrate is accomplished with a modified pulsejet and optionally an ejector to assist in preventing oxidation. Metal such as Aluminum or Magnesium may be used. A pulsejet is first initiated by applying fuel, air, and a spark. Metal is inserted continuously in a high volume of metal into a combustion chamber of the pulsejet. The combustion is thereafter controlled resonantly at high frequency and the metal is heated to a molten state. The metal is then transported from the combustion chamber into a tailpipe of said pulsejet and is expelled therefrom at high velocity and deposited on a target substrate.

  18. Effect of antimicrobials applied on the surface of beef subprimals via an air-assisted electrostatic spraying system(ESS)or the Sprayed Lethality in Container(SLIC)method to control Shiga toxin-producing cells of Escherichia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We evaluated the efficacy of an air-assisted electrostatic spraying system (ESS) and/or the Sprayed Lethality in Container (SLIC®) method to deliver antimicrobials onto the surface of beef subprimals to reduce levels of Shiga toxin-producing cells of Escherichia coli (STEC). In brief, beef subprimal...

  19. Use of air-assisted electrostatic spraying system (ESS)or the sprayed lethality in container(SLIC) method to deliver anticmicrobials onto the surface of beef subprimals to ... shiga toxin-producing cells of Escherichia coli

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We evaluated the efficacy of an air-assisted electrostatic spraying system (ESS) and/or the Sprayed Lethality in Container (SLIC) method to deliver antimicrobials onto the surface of beef subprimals to reduce levels of Shiga toxin-producing Escherichia coli (STEC). Beef subprimals were surface inocu...

  20. A novel preparation method for drug nanocrystals and characterization by ultrasonic spray-assisted electrostatic adsorption

    PubMed Central

    Gao, Bing; Wang, Jun; Wang, Dunju; Zhu, Ziqiang; Qiao, Zhiqiang; Yang, Guangcheng; Nie, Fude

    2013-01-01

    Purpose The purpose of this study was to develop a novel and continuous method for preparing a nanosized particle of drug crystals and to characterize its properties. Materials and methods A new apparatus was introduced to crystallize nanosized drug crystals of amitriptyline hydrochloride as a model drug. The samples were prepared in the pure state by ultrasonic spray, and elaborated deposition was completed via electrostatic adsorption. Scanning electron microscopy, X-ray powder diffraction, and atomic force microscopy were used to characterize the size of the particles; this was subsequently followed by differential scanning calorimetry. Results and discussion Nanoparticles of drug crystals were successfully prepared. The size of the drug crystals ranged from 20 nm to 400 nm; the particle size of amitriptyline hydrochloride was approximately 71 nm. The particles were spherical and rectangular in shape. Moreover, the melting point of the nanoparticles decreased from 198.2°C to 196.3°C when compared to raw particle crystals. Furthermore, the agglomeration effect was also attenuated as a result of electrostatic repulsion among each particle when absorbed, and depositing on the inner wall of the gathering unit occurred under the electrostatic effect. Conclusion Ultrasonic spray-assisted electrostatic adsorption is a very effective and continuous method to produce drug nanocrystals. This method can be applied to poorly water-soluble drugs, and it can also be a very effective alternative for industrial production. Once the working parameters are given, drug nanocrystals will be produced continuously. PMID:24143097

  1. Chemical spray pyrolysis of Tl-Ba-Ca-Cu-O high-T(sub c) superconductors for high-field bitter magnets

    NASA Technical Reports Server (NTRS)

    Derochemont, L. Pierre; Zhang, John G.; Squillante, Michael R.; Hermann, A. M.; Duan, H. M.; Andrews, Robert J.; Kelliher, Warren C.

    1991-01-01

    The deposition of Tl-Ba-Ca-Cu-O thick films by spray pyrolyzing a Ba-Ca-Cu-O precursor film and diffusing thallium into the film to form the superconducting phase is examined. This approach was taken to reduce exposure to thallium and its health and safety hazards. The Tl-Ba-Ca-Cu-O system was selected because it has very attractive features which make it appealing to device and manufacturing engineering. Tl-Ba-Ca-Cu-O will accommodate a number of superconducting phases. This attribute makes it very forgiving to stoichiometric fluctuations in the bulk and film. It has excellent thermal and chemical stability, and appears to be relatively insensitive to chemical impurities. Oxygen is tightly bound into the systems, consequently there is no orthorhombic (conductor) to tetragonal (insulator) transition which would affect a component's lifetime. More significantly, the thallium based superconductors appear to have harder magnetic properties than the other high-Tc oxide ceramics. Estimates using magnetoresistance measurements indicate that at 77 K Tl2Ba2CaCu2O10 will have an upper critical field, H(sub c2) fo 26 Tesla for applied fields parallel to the c-axis and approximately 1000 Tesla for fields oriented in the a-b plane. Results to date have shown that superconducting films can be reproducibly deposited on 100 oriented MgO substrates. One film had a zero resistance temperature of 111.5 K. Furthermore, x ray diffraction analysis of the films showed preferential c-axis orientation parallel to the plane of the substrate. These results have now made it possible to consider the manufacture of a superconducting tape wire which can be configured into a topology useful for high-field magnet designs. The research which leads to the preparation of these films and plans for further development are reviewed.

  2. Gas phase temperature measurements in the liquid and particle regime of a flame spray pyrolysis process using O2-based pure rotational coherent anti-Stokes Raman scattering.

    PubMed

    Engel, Sascha R; Koegler, Andreas F; Gao, Yi; Kilian, Daniel; Voigt, Michael; Seeger, Thomas; Peukert, Wolfgang; Leipertz, Alfred

    2012-09-01

    For the production of oxide nanoparticles at a commercial scale, flame spray processes are frequently used where mostly oxygen is fed to the flame if high combustion temperatures and thus small primary particle sizes are desired. To improve the understanding of these complex processes in situ, noninvasive optical measurement techniques were applied to characterize the extremely turbulent and unsteady combustion field at those positions where the particles are formed from precursor containing organic solvent droplets. This particle-forming regime was identified by laser-induced breakdown detection. The gas phase temperatures in the surrounding of droplets and particles were measured with O(2)-based pure rotational coherent anti-Stokes Raman scattering (CARS). Pure rotational CARS measurements benefit from a polarization filtering technique that is essential in particle and droplet environments for acquiring CARS spectra suitable for temperature fitting. Due to different signal disturbing processes only the minority of the collected signals could be used for temperature evaluation. The selection of these suitable signals is one of the major problems to be solved for a reliable evaluation process. Applying these filtering and signal selection steps temperature measurements have successfully been conducted. Time-resolved, single-pulse measurements exhibit temperatures between near-room and combustion temperatures due to the strongly fluctuating and flickering behavior of the particle-generating flame. The mean flame temperatures determined from the single-pulse data are decreasing with increasing particle concentrations. They indicate the dissipation of large amounts of energy from the surrounding gas phase in the presence of particles.

  3. Dermal exposure to dry powder spray paints using PXRF and the method of Dirichlet tesselations.

    PubMed

    Roff, Martin; Bagon, David A; Chambers, Helen; Dilworth, E Martin; Warren, Nicholas

    2004-04-01

    This paper describes workplace dermal exposure measurements that were carried out by the Health and Safety Laboratory as part of the EU RISKOFDERM project to measure dust contamination. Exposure to dry powder spray paints was measured at five sites on 12 subjects. Twenty-two samples were obtained, of which eight contained triglycidyl isocyanurate (TGIC) and 14 did not. All subjects wore Tyvek whole body oversuits and some wore sampling gloves. These were either analysed in their entirety to extract the TGIC or surface scanned over representative areas using a portable X-ray fluorescence spectrometer (PXRF) to detect barium or titanium in the fillers of the paints. The method of Dirichlet tessellation was used to map the scans and the technique was developed further for these studies to extend measurements to gloves and to take limits of detection into consideration. The PXRF allowed dusts to be measured in situ that would otherwise be difficult to extract from the material and analyse by other means. The geometric mean surface loading rate of the 22 oversuits was 43 micro g/cm/(2)/h (GSD = 6.0) and of the 23 pairs of sampling gloves was 970 micro g/cm(2)/h (GSD = 8.6). Exposure patterns could be attributed to the arrangements of the subjects, spray booths and the workpieces. Similar exposures were found for TGIC and titanium fillers in factories with similar methods of ventilation.

  4. Deposition of titanium nitride layers by electric arc - Reactive plasma spraying method

    NASA Astrophysics Data System (ADS)

    Şerban, Viorel-Aurel; Roşu, Radu Alexandru; Bucur, Alexandra Ioana; Pascu, Doru Romulus

    2013-01-01

    Titanium nitride (TiN) is a ceramic material which possesses high mechanical properties, being often used in order to cover cutting tools, thus increasing their lifetime, and also for covering components which are working in corrosive environments. The paper presents the experimental results on deposition of titanium nitride coatings by a new combined method (reactive plasma spraying and electric arc thermal spraying). In this way the advantages of each method in part are combined, obtaining improved quality coatings in the same time achieving high productivity. Commercially pure titanium wire and C45 steel as substrate were used for experiments. X-ray diffraction analysis shows that the deposited coatings are composed of titanium nitride (TiN, Ti2N) and small amounts of Ti3O. The microstructure of the deposited layers, investigated both by optical and scanning electron microscopy, shows that the coatings are dense, compact, without cracks and with low porosity. Vickers microhardness of the coatings presents maximum values of 912 HV0.1. The corrosion tests in 3%NaCl solution show that the deposited layers have a high corrosion resistance compared to unalloyed steel substrate.

  5. The Effect of Three Different Disinfection Materials on Alginate Impression by Spray Method

    PubMed Central

    Badrian, Hamid; Ghasemi, Ehsan; Khalighinejad, Navid; Hosseini, Nafiseh

    2012-01-01

    Introduction. The aim of this study was to investigate the effect of three different types of disinfectant agents on alginate impression material after 5 and 10 minutes. Method and Materials. In this in vitro experimental study, 66 circular samples of alginate impression material were contaminated with Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans fungus. Except for control samples, all of them were disinfected with sodium hypochlorite 0.525, Deconex, and Epimax by way of spraying. Afterwards, they were kept in plastic bags with humid rolled cotton for 5 and 10 minutes. The number of colonies was counted after 24 and 48 hours for bacteria and after 72 hours for fungus. Statistical Mann-Whitney test was used for data analysis (α = 0.05). Results. After 5 minutes, Epimax showed the highest disinfection action on Staphylococcus aureus as it completely eradicated the bacteria. The disinfection capacity of different agents can be increased as time elapses except for Pseudomonas aeruginosa which was eradicated completely in both 5 and 10 minutes. Conclusion. This study revealed that alginate can be effectively disinfected by three types of disinfecting agents by spraying method, although Epimax showed the highest disinfection action after 10 minutes compared to other agents. PMID:22900196

  6. Protective effects of oral microencapsulated Mycoplasma hyopneumoniae vaccine prepared by co-spray drying method.

    PubMed

    Lin, J H; Weng, C N; Liao, C W; Yeh, K S; Pan, M J

    2003-01-01

    The efficacy of Mycoplasma hyopneumoniae oral vaccine was investigated in microsphere dosage form. A co-spray drying process was used to apply an encapsulating material, Eudragit L30 D-55, to microspheres containing Mycoplasma hyopneumoniae antigens. The microspheres were generally effective (>93%) with protein release at pH 7.4, but almost none were released at pH 1.2, for 3 hr in an in vitro dissolution test. An SPF-swine model was used to evaluate the effectiveness of the microspheres as an oral vaccine, and the related immune responses. The serum's systemic IgG against M. hyopneumoniae was evoked by ELISA analysis, after a 2nd immunization of all pigs. The vaccinated groups' mean lesion score was significantly lower after the Mycoplasma hyopneumoniae challenge than that of the nonvaccinated/challenged groups (P<0.05). This study strongly suggests that the oral microspheres vaccine prepared by a co-spray drying method can provide effective protection against M. hyopneumoniae infection in pigs.

  7. Anisotropic Mechanical Properties of Plasma-Sprayed Thermal Barrier Coatings at High Temperature Determined by Ultrasonic Method

    NASA Astrophysics Data System (ADS)

    Wei, Qin; Zhu, Jianguo; Chen, Wei

    2016-02-01

    The mechanical properties of plasma-sprayed thermal barrier coatings (TBC) are of great scientific and technological significance for the design and fabrication of TBC systems. The ultrasonic method combined with a sing-around method for mechanical properties measurement of TBC is deduced and the elastic modulus can be determined in the spray, or longitudinal, direction, and the transverse direction. Tested specimens of plasma-sprayed TBC are detached from the substrate and treated with thermal exposure at 1400 °C. The elastic moduli along the longitudinal and transverse directions of the TBCs are measured by different types of ultrasonic waves combined with a sing-around method, while the Poisson's ratio is also obtained simultaneously. The experimental results indicate that the magnitude of longitudinal elastic modulus is larger than that of the transverse one, and thus the plasma-sprayed TBC has an anisotropic mechanical property. Moreover, the elastic moduli along both longitudinal and transverse directions change with high-temperature exposure time, which consists of a rapid increasing stage followed by a slow decreasing stage. In addition, the magnitude of Poisson's ratio increases slightly from 0.05 to 0.2 with the high-temperature exposure time. Generally, the microstructures in the plasma-sprayed coatings and their evolution in a high-temperature environment are the main causes of the varying anisotropic mechanical properties.

  8. Constrained Response Surface Optimisation and Taguchi Methods for Precisely Atomising Spraying Process

    NASA Astrophysics Data System (ADS)

    Luangpaiboon, P.; Suwankham, Y.; Homrossukon, S.

    2010-10-01

    This research presents a development of a design of experiment technique for quality improvement in automotive manufacturing industrial. The quality of interest is the colour shade, one of the key feature and exterior appearance for the vehicles. With low percentage of first time quality, the manufacturer has spent a lot of cost for repaired works as well as the longer production time. To permanently dissolve such problem, the precisely spraying condition should be optimized. Therefore, this work will apply the full factorial design, the multiple regression, the constrained response surface optimization methods or CRSOM, and Taguchi's method to investigate the significant factors and to determine the optimum factor level in order to improve the quality of paint shop. Firstly, 2κ full factorial was employed to study the effect of five factors including the paint flow rate at robot setting, the paint levelling agent, the paint pigment, the additive slow solvent, and non volatile solid at spraying of atomizing spraying machine. The response values of colour shade at 15 and 45 degrees were measured using spectrophotometer. Then the regression models of colour shade at both degrees were developed from the significant factors affecting each response. Consequently, both regression models were placed into the form of linear programming to maximize the colour shade subjected to 3 main factors including the pigment, the additive solvent and the flow rate. Finally, Taguchi's method was applied to determine the proper level of key variable factors to achieve the mean value target of colour shade. The factor of non volatile solid was found to be one more additional factor at this stage. Consequently, the proper level of all factors from both experiment design methods were used to set a confirmation experiment. It was found that the colour shades, both visual at 15 and 45 angel of measurement degrees of spectrophotometer, were nearly closed to the target and the defective at

  9. Thermal sprayed composite melt containment tubular component and method of making same

    DOEpatents

    Besser, Matthew F.; Terpstra, Robert L.; Sordelet, Daniel J.; Anderson, Iver E.

    2002-03-19

    A tubular thermal sprayed melt containment component for transient containment of molten metal or alloy wherein the tubular member includes a thermal sprayed inner melt-contacting layer for contacting molten metal or alloy to be processed, a thermal sprayed heat-generating layer deposited on the inner layer, and an optional thermal sprayed outer thermal insulating layer. The thermal sprayed heat-generating layer is inductively heated as a susceptor of an induction field or electrical resistively heated by passing electrical current therethrough. The tubular thermal sprayed melt containment component can comprise an elongated melt pour tube of a gas atomization apparatus where the melt pour tube supplies molten material from a crucible to an underlying melt atomization nozzle.

  10. Effects of fuel cetane number on the structure of diesel spray combustion: An accelerated Eulerian stochastic fields method

    NASA Astrophysics Data System (ADS)

    Jangi, Mehdi; Lucchini, Tommaso; Gong, Cheng; Bai, Xue-Song

    2015-09-01

    An Eulerian stochastic fields (ESF) method accelerated with the chemistry coordinate mapping (CCM) approach for modelling spray combustion is formulated, and applied to model diesel combustion in a constant volume vessel. In ESF-CCM, the thermodynamic states of the discretised stochastic fields are mapped into a low-dimensional phase space. Integration of the chemical stiff ODEs is performed in the phase space and the results are mapped back to the physical domain. After validating the ESF-CCM, the method is used to investigate the effects of fuel cetane number on the structure of diesel spray combustion. It is shown that, depending of the fuel cetane number, liftoff length is varied, which can lead to a change in combustion mode from classical diesel spray combustion to fuel-lean premixed burned combustion. Spray combustion with a shorter liftoff length exhibits the characteristics of the classical conceptual diesel combustion model proposed by Dec in 1997 (http://dx.doi.org/10.4271/970873), whereas in a case with a lower cetane number the liftoff length is much larger and the spray combustion probably occurs in a fuel-lean-premixed mode of combustion. Nevertheless, the transport budget at the liftoff location shows that stabilisation at all cetane numbers is governed primarily by the auto-ignition process.

  11. The structure of Fe-Cr-B coatings obtained using selected methods of thermal spraying

    NASA Astrophysics Data System (ADS)

    Szymański, K.; Szpak, M.

    2012-05-01

    This paper presents issues connected with the production of protective coatings via thermal spraying. Information about wire coating materials which contain phases from the Fe-Cr-B system is presented. Arc thermal spraying is characterised and its possible applications are determined. The results of the examinations of the structure of coatings obtained by means of various arc spraying systems are discussed. Coatings of this type are used in the machine building and power engineering industries.

  12. Determination of Carbonyl Groups in Pyrolysis Bio-oils Using Potentiometric Titration: Review and Comparison of Methods

    SciTech Connect

    Black, Stuart; Ferrell, Jack R.

    2016-01-06

    Carbonyl compounds present in bio-oils are known to be responsible for bio-oil property changes upon storage and during upgrading. As such, carbonyl content has previously been used as a method of tracking bio-oil aging and condensation reactions with less variability than viscosity measurements. Given the importance of carbonyls in bio-oils, accurate analytical methods for their quantification are very important for the bio-oil community. Potentiometric titration methods based on carbonyl oximation have long been used for the determination of carbonyl content in pyrolysis bio-oils. Here in this study, we present a modification of the traditional carbonyl oximation procedures that results in less reaction time, smaller sample size, higher precision, and more accurate carbonyl determinations. Some compounds such as carbohydrates are not measured by the traditional method (modified Nicolaides method), resulting in low estimations of the carbonyl content. Furthermore, we have shown that reaction completion for the traditional method can take up to 300 hours. The new method presented here (the modified Faix method) reduces the reaction time to 2 hours, uses triethanolamine (TEA) in the place of pyridine, and requires a smaller sample size for the analysis. Carbonyl contents determined using this new method are consistently higher than when using the traditional titration methods.

  13. Determination of Carbonyl Groups in Pyrolysis Bio-oils Using Potentiometric Titration: Review and Comparison of Methods

    DOE PAGES

    Black, Stuart; Ferrell, Jack R.

    2016-01-06

    Carbonyl compounds present in bio-oils are known to be responsible for bio-oil property changes upon storage and during upgrading. As such, carbonyl content has previously been used as a method of tracking bio-oil aging and condensation reactions with less variability than viscosity measurements. Given the importance of carbonyls in bio-oils, accurate analytical methods for their quantification are very important for the bio-oil community. Potentiometric titration methods based on carbonyl oximation have long been used for the determination of carbonyl content in pyrolysis bio-oils. Here in this study, we present a modification of the traditional carbonyl oximation procedures that results inmore » less reaction time, smaller sample size, higher precision, and more accurate carbonyl determinations. Some compounds such as carbohydrates are not measured by the traditional method (modified Nicolaides method), resulting in low estimations of the carbonyl content. Furthermore, we have shown that reaction completion for the traditional method can take up to 300 hours. The new method presented here (the modified Faix method) reduces the reaction time to 2 hours, uses triethanolamine (TEA) in the place of pyridine, and requires a smaller sample size for the analysis. Carbonyl contents determined using this new method are consistently higher than when using the traditional titration methods.« less

  14. Molecular characterization and comparison of shale oils generated by different pyrolysis methods using FT-ICR mass spectrometry

    USGS Publications Warehouse

    Jin, J.M.; Kim, S.; Birdwell, J.E.

    2011-01-01

    Fourier transform ion cyclotron resonance mass spectrometry (FT ICR-MS) was applied in the analysis of shale oils generated using two different pyrolysis systems under laboratory conditions meant to simulate surface and in situ oil shale retorting. Significant variations were observed in the shale oils, particularly the degree of conjugation of the constituent molecules. Comparison of FT ICR-MS results to standard oil characterization methods (API gravity, SARA fractionation, gas chromatography-flame ionization detection) indicated correspondence between the average Double Bond Equivalence (DBE) and asphaltene content. The results show that, based on the average DBE values and DBE distributions of the shale oils examined, highly conjugated species are enriched in samples produced under low pressure, high temperature conditions and in the presence of water.

  15. Influence of Starting Powders on Hydroxyapatite Coatings Fabricated by Room Temperature Spraying Method.

    PubMed

    Seo, Dong Seok; Lee, Jong Kook; Hwang, Kyu Hong; Hahn, Byung Dong; Yoon, Seog Young

    2015-08-01

    Three types of raw materials were used for the fabrication of hydroxyapatite coatings by using the room temperature spraying method and their influence on the microstructure and in vitro characteristics were investigated. Starting hydroxyapatite powders for coatings on titanium substrate were prepared by a heat treatment at 1100 °C for 2 h of bovine bone, bone ash, and commercial hydroxyapatite powders. The phase compositions and Ca/P ratios of the three hydroxyapatite coatings were similar to those of the raw materials without decomposition or formation of a new phase. All hydroxyapatite coatings showed a honeycomb structure, but their surface microstructures revealed different features in regards to surface morphology and roughness, based on the staring materials. All coatings consisted of nano-sized grains and had dense microstructure. Inferred from in vitro experiments in pure water, all coatings have a good dissolution-resistance and biostability in water.

  16. Method and Apparatus for Thermal Spraying of Metal Coatings Using Pulsejet Resonant Pulsed Combustion

    NASA Technical Reports Server (NTRS)

    Paxson, Daniel E. (Inventor)

    2010-01-01

    An apparatus and method [or thermal spraying a metal coating on a substrate is accomplished with a modified pulsejet and optionally an ejector to assist in preventing oxidation. Metal such a Aluminum or Magnesium may be used. A pulsejet is first initiated by applying fuel, air. and a spark. Metal is inserted continuously in a high volume of meta1 into a combustion chamber of the pulsejet. The combustion is thereafter. controlled resonantly at high frequency and the metal is heated to a molten state. The metal is then transported from the combustion chamber into a tail pipe of said pulsejet and is expelled therefrom at high velocity and deposited on a target substrate.

  17. Optimization of the HOVF Spray Parameters by Taguchi Method for High Corrosion-Resistant Fe-Based Coatings

    NASA Astrophysics Data System (ADS)

    Qin, Yujiao; Wu, Yuping; Zhang, Jianfeng; Hong, Sheng; Guo, Wenmin; Chen, Liyan; Liu, Hao

    2015-07-01

    Taguchi method was used to optimize the parameters of the high velocity oxygen fuel (HVOF) spray process and obtain the high corrosion-resistant Fe-based coatings. Based on the signal-to-noise ( S/ N) ratio and the analysis of variance, the significance of spray parameters in determining the porosity of the coatings was found to be in the order of spray distance, oxygen flow, and kerosene flow. Thus, the optimal parameters for the porosity of the HVOF sprayed Fe-based coating were determined as 280 mm for the spray distance, 963 scfh for the oxygen flow, and 28 gph for the kerosene flow. The potentiodynamic polarization and EIS tests indicated that the Fe-based coating prepared with the optimal parameters exhibited a higher corrosion potential ( E corr) of -196.14 mV, a lower corrosion current density ( i corr) of 0.14 μA/cm2, and a higher coating resistance ( R c) of 2.26 × 106 Ω cm2 than those of the hard chromium coating in 3.5% sodium chloride solution. This superior corrosion resistance could be attributed to the dense structure with low porosity and partially amorphous phases of the Fe-based coatings.

  18. Development and Characterization of Multifunctional Directly Compressible Co-processed Excipient by Spray Drying Method.

    PubMed

    Chauhan, Sohil I; Nathwani, Sandeep V; Soniwala, Moinuddin M; Chavda, Jayant R

    2016-08-01

    The present investigation was carried out to develop and characterize a multifunctional co-processed excipient for improving the compressibility of poorly compressible drugs. Etodolac was used as a model drug. Microcrystalline cellulose (MCC), lactose monohydrate (lactose), and StarCap 1500 (StarCap) were selected as components of the co-processed excipient. The spray drying method was used for co-processing of excipients. D-optimal mixture design was applied to optimize the proportion of component excipients. Statistical analysis of the D-optimal mixture design revealed that all response variables were significantly affected by the independent variables (p value < 0.05). Optimized composition was obtained from the desirability function. The optimized composition of the co-processed excipient was found to be 30% MCC, 25% lactose, and 45% StarCap. This optimized batch was evaluated for flow properties, compressibility parameters such as Kawakita's and Kuno's equation and Heckel's equation, and dilution potential. Evaluation parameters for flow properties (angle of repose, Carr's index, and Hausner's ratio) suggested excellent flow character. The parameters of Kawakita's and Kuno's equation and Heckel's equation suggested improvement in the compressibility of the model drug. Dilution potential was found to be 40%, and based on that, tablets of the model drug were formulated and evaluated for general evaluation parameters of tablets. All the parameters were found to be within the acceptance criteria which concluded that the multifunctional directly compressible co-processed excipient was prepared successfully that improved the compressibility of the poorly compressible model drug etodolac along with spray drying as an efficient method for the preparation of co-processed excipient.

  19. Melt extrusion vs. spray drying: The effect of processing methods on crystalline content of naproxen-povidone formulations.

    PubMed

    Haser, Abbe; Cao, Tu; Lubach, Joe; Listro, Tony; Acquarulo, Larry; Zhang, Feng

    2017-03-01

    Our hypothesis is that melt extrusion is a more suitable processing method than spray drying to prepare amorphous solid dispersions of drugs with a high crystallization tendency. Naproxen-povidone K25 was used as the model system in this study. Naproxen-povidone K25 solid dispersions at 30% and 60% drug loadings were characterized by modulated DSC, powder X-ray diffraction, FT-IR, and solid-state (13)C NMR to identify phase separation and drug recrystallization during processing and storage. At 30% drug loading, hydrogen bond (H-bond) sites of povidone K25 were not saturated and the glass transition (Tg) temperature of the formulation was higher. As a result, both melt-extruded and spray-dried materials were amorphous initially and remained so after storage at 40°C. At 60% drug loading, H-bond sites were saturated, and Tg was low. We were not able to prepare amorphous materials. The initial crystallinity of the formulations was 0.4%±0.2% and 5.6%±0.6%, and increased to 2.7%±0.3% and 21.6%±1.0% for melt-extruded and spray-dried materials, respectively. Spray-dried material was more susceptible to re-crystallization during processing, due to the high diffusivity of naproxen molecules in the formulation matrix and lack of kinetic stabilization from polymer solution. A larger number of crystalline nucleation sites and high surface area made the spray-dried material more susceptible to recrystallization during storage. This study demonstrated the unique advantages of melt extrusion over spray drying for the preparation of amorphous solid dispersions of naproxen at high drug level.

  20. Paper spray mass spectrometry-based method for analysis of droplets in a gravity-driven microfluidic chip.

    PubMed

    Zhang, Yandong; Li, Haifang; Ma, Yuan; Lin, Jin-Ming

    2014-03-07

    This work presents a paper spray mass spectrometry-based method, to analyze microdroplets produced in a gravity-driven microchip. Droplets at ambient pressure were passively transferred from the chip to a paper substrate by the capillary wicking effect. Paper spray ionization was then performed for mass spectrometry (MS) analysis of droplet contents. The qualitative and quantitative analytical performances of this technique for single droplets were demonstrated. This manually controlled interface is straightforward, low-cost and simple to implement. Moreover, paper spray ionization MS holds promise in the direct analysis of real biological/chemical microreaction samples because of its tolerance with complex matrices. As a proof-of-concept example, the droplet-based acetylcholine hydrolysis was carried out to demonstrate the validation of our method for the direct analysis of micro-chemical/biological reactions. We also introduced a flow injection analysis (FIA) system combined with our droplet system to generate a concentration gradient. As a result, the microreaction can be performed at different concentrations and kinetic information can be obtained in one sample injection. In conclusion, the combination of a microdroplet chip with paper spray ionization and the introduction of the FIA system and make our droplet-MS scheme a useful platform for monitoring and analyzing organic-phase chemical/biological reactions.

  1. Friability of spray-applied fireproofing and thermal insulations: the basis for a field-test method

    SciTech Connect

    Rossiter, W.J.; Roberts, W.E.; Mathey, R.G.

    1987-12-01

    The investigation was Phase 1 of a two-part study to develop a test method that can be used in the field to measure the friability of spray-applied fireproofing and insulating materials containing asbestos fibers. Four test methods were selected; compression/shear, indentation, abrasion, and impact. For each of the four tests, mechanical devices were devised by modification of existing material test apparatus. A description of the test devices is given in the report.

  2. Miniature spray-painting booth

    NASA Technical Reports Server (NTRS)

    Fee, K. W.

    1970-01-01

    Transparent spray booth provides method for quality painting and repair of surfaces in clean room or other specialized environments. Overspray and virtually all contaminating vapor and odor can be eliminated. Touch-up painting is achieved with spray gun.

  3. Nasal spray flu vaccine (image)

    MedlinePlus

    The flu vaccine can also be administered as a nasal spray instead of the usual injection method. It can be ... the recombinant influenza vaccine (RIV). The nasal spray flu vaccine (live attenuated influenza vaccine or LAIV) should not ...

  4. Lake spray aerosol generation: a method for producing representative particles from freshwater wave breaking

    NASA Astrophysics Data System (ADS)

    May, Nathaniel W.; Axson, Jessica L.; Watson, Alexa; Pratt, Kerri A.; Ault, Andrew P.

    2016-09-01

    Wave-breaking action in bodies of freshwater produces atmospheric aerosols via a similar mechanism to sea spray aerosol (SSA) from seawater. The term lake spray aerosol (LSA) is proposed to describe particles formed by this mechanism, which have been observed over the Laurentian Great Lakes. Though LSA has been identified from size distribution measurements during a single measurement campaign, no measurements of LSA composition or relationship to bubble-bursting dynamics have been conducted. An LSA generator utilizing a plunging jet, similar to many SSA generators, was constructed for the generation of aerosol from freshwater samples and model salt solutions. To evaluate this new generator, bubble and aerosol number size distributions were measured for salt solutions representative of freshwater (CaCO3) and seawater (NaCl) at concentrations ranging from that of freshwater to seawater (0.05-35 g kg-1), synthetic seawater (inorganic), synthetic freshwater (inorganic), and a freshwater sample from Lake Michigan. Following validation of the bubble and aerosol size distributions using synthetic seawater, a range of salt concentrations were investigated. The systematic studies of the model salts, synthetic freshwater, and Lake Michigan sample indicate that LSA is characterized by a larger number size distribution mode diameter of 300 nm (lognormal), compared to seawater at 110 nm. Decreasing salt concentrations from seawater to freshwater led to greater bubble coalescence and formation of larger bubbles, which generated larger particles and lower aerosol number concentrations. This resulted in a bimodal number size distribution with a primary mode (180 ± 20 nm) larger than that of SSA, as well as a secondary mode (46 ± 6 nm) smaller than that of SSA. This new method for studying LSA under isolated conditions is needed as models, at present, utilize SSA parameterizations for freshwater systems, which do not accurately predict the different size distributions observed

  5. A semi-Lagrangian transport method for kinetic problems with application to dense-to-dilute polydisperse reacting spray flows

    NASA Astrophysics Data System (ADS)

    Doisneau, François; Arienti, Marco; Oefelein, Joseph C.

    2017-01-01

    For sprays, as described by a kinetic disperse phase model strongly coupled to the Navier-Stokes equations, the resolution strategy is constrained by accuracy objectives, robustness needs, and the computing architecture. In order to leverage the good properties of the Eulerian formalism, we introduce a deterministic particle-based numerical method to solve transport in physical space, which is simple to adapt to the many types of closures and moment systems. The method is inspired by the semi-Lagrangian schemes, developed for Gas Dynamics. We show how semi-Lagrangian formulations are relevant for a disperse phase far from equilibrium and where the particle-particle coupling barely influences the transport; i.e., when particle pressure is negligible. The particle behavior is indeed close to free streaming. The new method uses the assumption of parcel transport and avoids to compute fluxes and their limiters, which makes it robust. It is a deterministic resolution method so that it does not require efforts on statistical convergence, noise control, or post-processing. All couplings are done among data under the form of Eulerian fields, which allows one to use efficient algorithms and to anticipate the computational load. This makes the method both accurate and efficient in the context of parallel computing. After a complete verification of the new transport method on various academic test cases, we demonstrate the overall strategy's ability to solve a strongly-coupled liquid jet with fine spatial resolution and we apply it to the case of high-fidelity Large Eddy Simulation of a dense spray flow. A fuel spray is simulated after atomization at Diesel engine combustion chamber conditions. The large, parallel, strongly coupled computation proves the efficiency of the method for dense, polydisperse, reacting spray flows.

  6. Influence of Particle Velocity of Copper on Emitter Contact by Cold-Spray Method

    NASA Astrophysics Data System (ADS)

    Kang, Byungjun; Lee, Kyung Dong; Lee, Jong-gun; Choi, Jae-Wook; Yoon, Sam S.; Kang, Yoonmook; Lee, Hae-seok; Kim, Donghwan

    2016-02-01

    In this study, we investigated cold-sprayed copper as a front contact for crystalline silicon solar cells. Copper powder was deposited on a monocrystalline silicon wafer with variation of the particle velocity during deposition. The particle velocity was varied by varying the heating temperature from 250 to 400 °C using a gas pressure of 0.45 MPa. The particle velocities were calculated using empirical equations, and were found to increase with an increase in the carrier gas temperature. Grid patterns were formed on a phosphorus-doped n-type emitter of a p-type silicon substrate. The electrode thickness increased with increasing particle velocity. The electrical properties of the grids were evaluated using the transfer length method. The specific contact resistance of the n-type emitter was in the range of 2.6-26.4 mΩ-cm2. Damage to the p- n junction was investigated via minority carrier lifetime measurement of the substrate. The copper-silicon interface was evaluated using transmission electron microscopy. The contact properties were affected by the interface conditions.

  7. Method for minimizing decarburization and other high temperature oxygen reactions in a plasma sprayed material

    DOEpatents

    Lenling, William J.; Henfling, Joseph A.; Smith, Mark F.

    1993-06-08

    A method is disclosed for spray coating material which employs a plasma gun that has a cathode, an anode, an arc gas inlet, a first powder injection port, and a second powder injection port. A suitable arc gas is introduced through the arc gas inlet, and ionization of the arc gas between the cathode and the anode forms a plasma. The plasma is directed to emenate from an open-ended chamber defined by the boundary of the anode. A coating is deposited upon a base metal part by suspending a binder powder within a carrier gas that is fed into the plasma through the first powder injection port; a material subject to degradation by high temperature oxygen reactions is suspended within a carrier gas that is fed into the plasma through the second injection port. The material fed through the second injection port experiences a cooler portion of the plasma and has a shorter dwell time within the plasma to minimize high temperature oxygen reactions. The material of the first port and the material of the second port intermingle within the plasma to form a uniform coating having constituent percentages related to the powder-feed rates of the materials through the respective ports.

  8. Standardization of chemical analytical techniques for pyrolysis bio-oil: history, challenges, and current status of methods

    DOE PAGES

    Ferrell, Jack R.; Olarte, Mariefel V.; Christensen, Earl D.; ...

    2016-07-05

    Here, we discuss the standardization of analytical techniques for pyrolysis bio-oils, including the current status of methods, and our opinions on future directions. First, the history of past standardization efforts is summarized, and both successful and unsuccessful validation of analytical techniques highlighted. The majority of analytical standardization studies to-date has tested only physical characterization techniques. In this paper, we present results from an international round robin on the validation of chemical characterization techniques for bio-oils. Techniques tested included acid number, carbonyl titrations using two different methods (one at room temperature and one at 80 °C), 31P NMR for determination ofmore » hydroxyl groups, and a quantitative gas chromatography–mass spectrometry (GC-MS) method. Both carbonyl titration and acid number methods have yielded acceptable inter-laboratory variabilities. 31P NMR produced acceptable results for aliphatic and phenolic hydroxyl groups, but not for carboxylic hydroxyl groups. As shown in previous round robins, GC-MS results were more variable. Reliable chemical characterization of bio-oils will enable upgrading research and allow for detailed comparisons of bio-oils produced at different facilities. Reliable analytics are also needed to enable an emerging bioenergy industry, as processing facilities often have different analytical needs and capabilities than research facilities. We feel that correlations in reliable characterizations of bio-oils will help strike a balance between research and industry, and will ultimately help to -determine metrics for bio-oil quality. Lastly, the standardization of additional analytical methods is needed, particularly for upgraded bio-oils.« less

  9. Standardization of chemical analytical techniques for pyrolysis bio-oil: history, challenges, and current status of methods

    SciTech Connect

    Ferrell, Jack R.; Olarte, Mariefel V.; Christensen, Earl D.; Padmaperuma, Asanga B.; Connatser, Raynella M.; Stankovikj, Filip; Meier, Dietrich; Paasikallio, Ville

    2016-07-05

    Here, we discuss the standardization of analytical techniques for pyrolysis bio-oils, including the current status of methods, and our opinions on future directions. First, the history of past standardization efforts is summarized, and both successful and unsuccessful validation of analytical techniques highlighted. The majority of analytical standardization studies to-date has tested only physical characterization techniques. In this paper, we present results from an international round robin on the validation of chemical characterization techniques for bio-oils. Techniques tested included acid number, carbonyl titrations using two different methods (one at room temperature and one at 80 °C), 31P NMR for determination of hydroxyl groups, and a quantitative gas chromatography–mass spectrometry (GC-MS) method. Both carbonyl titration and acid number methods have yielded acceptable inter-laboratory variabilities. 31P NMR produced acceptable results for aliphatic and phenolic hydroxyl groups, but not for carboxylic hydroxyl groups. As shown in previous round robins, GC-MS results were more variable. Reliable chemical characterization of bio-oils will enable upgrading research and allow for detailed comparisons of bio-oils produced at different facilities. Reliable analytics are also needed to enable an emerging bioenergy industry, as processing facilities often have different analytical needs and capabilities than research facilities. We feel that correlations in reliable characterizations of bio-oils will help strike a balance between research and industry, and will ultimately help to -determine metrics for bio-oil quality. Lastly, the standardization of additional analytical methods is needed, particularly for upgraded bio-oils.

  10. Method and closing pores in a thermally sprayed doped lanthanum chromite interconnection layer

    DOEpatents

    Singh, Prabhakar; Ruka, Roswell J.

    1995-01-01

    A dense, substantially gas-tight electrically conductive interconnection layer is formed on an air electrode structure of an electrochemical cell by (A) providing an air electrode surface; (B) forming on a selected portion of the electrode surface, a layer of doped LaCrO.sub.3 particles doped with an element or elements selected from Ca, Sr, Ba, Mg, Co, Ni, Al and mixtures thereof by thermal spraying doped LaCrO.sub.3 particles, either by plasma arc spraying or flame spraying; (C) depositing a mixture of CaO and Cr.sub.2 O.sub.3 on the surface of the thermally sprayed layer; and (D) heating the doped LaCrO.sub.3 layer coated with CaO and Cr.sub.2 O.sub.3 surface deposit at from about 1000.degree. C. to 1200.degree. C. to substantially close the pores, at least at a surface, of the thermally sprayed doped LaCrO.sub.3 layer. The result is a dense, substantially gas-tight, highly doped, electrically conductive interconnection material bonded to the electrode surface. A solid electrolyte layer can be applied to the nonselected portion of the air electrode. A fuel electrode can be applied to the solid electrolyte, to form an electrochemical cell, for example for generation of electrical power.

  11. Method and closing pores in a thermally sprayed doped lanthanum chromite interconnection layer

    DOEpatents

    Singh, P.; Ruka, R.J.

    1995-02-14

    A dense, substantially gas-tight electrically conductive interconnection layer is formed on an air electrode structure of an electrochemical cell by (A) providing an air electrode surface; (B) forming on a selected portion of the electrode surface, a layer of doped LaCrO{sub 3} particles doped with an element or elements selected from Ca, Sr, Ba, Mg, Co, Ni, Al and mixtures thereof by thermal spraying doped LaCrO{sub 3} particles, either by plasma arc spraying or flame spraying; (C) depositing a mixture of CaO and Cr{sub 2}O{sub 3} on the surface of the thermally sprayed layer; and (D) heating the doped LaCrO{sub 3} layer coated with CaO and Cr{sub 2}O{sub 3} surface deposit at from about 1,000 C to 1,200 C to substantially close the pores, at least at a surface, of the thermally sprayed doped LaCrO{sub 3} layer. The result is a dense, substantially gas-tight, highly doped, electrically conductive interconnection material bonded to the electrode surface. A solid electrolyte layer can be applied to the nonselected portion of the air electrode. A fuel electrode can be applied to the solid electrolyte, to form an electrochemical cell, for example for generation of electrical power. 5 figs.

  12. Pyrolysis products of PCBs.

    PubMed Central

    Paasivirta, J; Herzschuh, R; Humppi, T; Kantolahti, E; Knuutinen, J; Lahtiperä, M; Laitinen, R; Salovaara, J; Tarhanen, J; Virkki, L

    1985-01-01

    Model compound studies which were previously done for impurities and environmental residues of chlorophenols and for wastes of chlorination processes were extended to the impurities and pyrolysis products of polychlorinated biphenyls (PCBs). Model compounds were commercial products or synthesized and their structures proven by spectroscopic methods. These models were used as analytical reference substances in GC/ECD and GC/MS studies of the pyrolyzed PCB samples. In addition to previously known neutral components like polychlorinated dibenzofurans (PCDFs), chlorophenolic substances, especially polychlorophenols (PCPs) and polychlorinated biphenylols (PCB-OHs) were observed as major pyrolysis products of PCBs. Capacitor fires are suggested to produce in many cases chlorophenols which are major toxic hazards to people. PMID:3928353

  13. Non-Destructive Evaluation of Thermal Spray Coating Interface Quality By Eddy Current Method

    SciTech Connect

    B. Mi; G. Zhao; R. Bayles

    2006-08-10

    Thermal spray coating is usually applied through directing molten or softened particles at very high velocities onto a substrate. An eddy current non-destructive inspection technique is presented here for thermal spray coating interface quality characterization. Several high-velocity-oxy-fuel (HVOF) coated steel plates were produced with various surface preparation conditions or spray process parameters. A quad-frequency eddy current probe was used to manually scan over the coating surface to evaluate the bonding quality. Experimental results show that different surface preparation conditions and varied process parameters can be successfully differentiated by the impedance value observed from the eddy current probe. The measurement is fairly robust and consistent. This non-contact, nondestructive, easy-to-use technique has the potential for evaluating the coating quality immediately after its application so that any defects can be corrected immediately.

  14. Method for Thermal Spraying of Coatings Using Resonant-Pulsed Combustion

    NASA Technical Reports Server (NTRS)

    Paxson, Daniel E.

    2008-01-01

    A method has been devised for high-volume, high-velocity surface deposition of protective metallic coatings on otherwise vulnerable surfaces. Thermal spraying is used whereby the material to be deposited is heated to the melting point by passing through a flame. Rather than the usual method of deposition from the jet formed from the combustion products, this innovation uses non-steady combustion (i.e. high-frequency, periodic, confined bursts), which generates not only higher temperatures and heat transfer rates, but exceedingly high impingement velocities an order of magnitude higher than conventional thermal systems. Higher impingement rates make for better adhesion. The high heat transfer rates developed here allow the deposition material to be introduced, not as an expensive powder with high surface-area-to-volume, but in convenient rod form, which is also easier and simpler to feed into the system. The nonsteady, resonant combustion process is self-aspirating and requires no external actuation or control and no high-pressure supply of fuel or air. The innovation has been demonstrated using a commercially available resonant combustor shown in the figure. Fuel is naturally aspirated from the tank through the lower Tygon tube and into the pulsejet. Air for starting is ported through the upper Tygon tube line. Once operation commences, this air is no longer needed as additional air is naturally aspirated through the inlet. A spark plug on the device is needed for starting, but the process carries on automatically as the operational device is resonant and reignites itself with each 220-Hz pulse.

  15. Microencapsulation of Lactobacillus plantarum (mtcc 5422) by spray-freeze-drying method and evaluation of survival in simulated gastrointestinal conditions.

    PubMed

    Dolly, Priyanka; Anishaparvin, A; Joseph, G S; Anandharamakrishnan, C

    2011-01-01

    Spray-drying (SD) and freeze-drying (FD) are widely used methods for microencapsulation of heat-sensitive materials like probiotics for long-term preservation and transport. Spray-freeze-drying (SFD) is relatively a new technique that involves spraying a solution into a cold medium and removal of solvent (water) by conventional vacuum FD method. In this study, the SFD microencapsulated Lactobacillus plantarum powder (1:1 and 1:1.5 core-to-wall ratios of whey protein) is compared with the microencapsulated powders produced by FD and SD methods. The SFD and FD processed microencapsulated powder show 20% higher cell viability than the SD samples. In simulated gastrointestinal conditions, the SFD and FD cells show up to 4 h better tolerance than SD samples and unencapsulated cells in acidic and pepsin condition. The morphology of SFD samples shows particles almost in spherical shape with numerous fine pores, which in turn results in good rehydration behaviour of the powdered product.

  16. An improved whitecap timescale for sea spray aerosol production flux modeling using the discrete whitecap method

    NASA Astrophysics Data System (ADS)

    Callaghan, Adrian H.

    2013-09-01

    The discrete whitecap method (DWM) to model the sea spray aerosol (SSA) production flux explicitly requires a whitecap timescale, which up to now has only considered a whitecap decay timescale, τdecay. A reevaluation of the DWM suggests that the whitecap timescale should account for the total whitecap lifetime (τwcap), which consists of both the formation timescale (τform) and the decay timescale (timescale definitions are given in the text). Here values of τform for 552 oceanic whitecaps measured at the Martha's Vineyard Coastal Observatory on the east coast of the USA are presented, and added to the corresponding values of τdecay to form 552 whitecap timescales. For the majority of whitecaps, τform makes up about 20-25% of τwcap, but this can be as large as 70% depending on the value of τdecay. Furthermore, an area-weighted mean whitecap timescale for use in the DWM (τDWM) is defined that encompasses the variable nature of individual whitecap lifetimes within a given time period, and is calculated to be 5.3 s for this entire data set. This value is combined with previously published whitecap coverage parameterizations and estimates of SSA particle production per whitecap area to form a size-resolved SSA production flux parameterization (dF(r80)/dlog10r80). This parameterization yields integrated sea-salt mass fluxes that are largely within the range of uncertainty of recent measurements over the size range 0.029 µm < r80 < 0.580 µm. Physical factors controlling whitecap lifetime such as bubble plume lifetime and surfactant stabilization are discussed in the context of SSA production from whitecaps.

  17. Evaluation of the Microcentrifuge Dissolution Method as a Tool for Spray-Dried Dispersion.

    PubMed

    Wu, Benjamin; Li, Jinjiang; Wang, Yahong

    2016-03-01

    Although using spray-dried dispersions (SDDs) to improve the bioavailability of poorly water-soluble compounds has become a common practice in supporting the early phases of clinical studies, their performance evaluation, whether in solid dosage forms or alone, still presents significant challenges. A microcentrifuge dissolution method has been reported to quickly assess the dissolution performance of SDDs. While the microcentrifuge dissolution method has been used in the SDD community, there is still a need to understand the mechanisms about the molecular species present in supernatant after centrifugation, the molecular nature of active pharmaceutical ingredients (APIs), as well as the impact of experimental conditions. In this paper, we aim to assess the effect of API and polymer properties on the dissolution behavior of SDDs along with centrifuging parameters, and for this, two poorly water-soluble compounds (indomethacin and ketoconazole) and two commonly used polymers in the pharmaceutical industry (PVP and HPMC-AS) were chosen to prepare SDDs. A typical microcentrifuge dissolution procedure as reported in the publication (Curatolo et al., Pharm Res 26:1419-1431, 2009) was followed. In addition, after separation of the supernatant from precipitation, some of the samples were filtered through filters of various sizes to investigate the particulate nature (particle size) of the supernatant. Furthermore, the centrifuge speed was varied to study sedimentation of API, SDD, or polymer particles. The results indicated that for the SDDs of four drug-polymer pairs, microcentrifuge dissolution exhibited varied behaviors, depending on the polymer and the drug used. The SDDs of indomethacin with either PVP or HPMC-AS showed a reproducible dissolution with minimum variability even after filtration and subjecting to varied centrifugation speed, suggesting that the supernatant behaved solution-like. However, ketoconazole-PVP and ketoconazole-HPMC-AS SDDs displayed a

  18. Production and analysis of fast pyrolysis oils from proteinaceous biomass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fast pyrolysis of lignocellulosic biomass is a facile method for producing high yields of liquid fuel intermediates. However, because most fast pyrolysis oils are highly oxygenated, acidic and unstable identification of feedstocks that produce higher quality pyrolysis liquids is desirable. Therefor...

  19. A Fast and Effective Microfluidic Spraying-Plunging Method for High-Resolution Single-Particle Cryo-EM.

    PubMed

    Feng, Xiangsong; Fu, Ziao; Kaledhonkar, Sandip; Jia, Yuan; Shah, Binita; Jin, Amy; Liu, Zheng; Sun, Ming; Chen, Bo; Grassucci, Robert A; Ren, Yukun; Jiang, Hongyuan; Frank, Joachim; Lin, Qiao

    2017-03-06

    We describe a spraying-plunging method for preparing cryoelectron microscopy (cryo-EM) grids with vitreous ice of controllable, highly consistent thickness using a microfluidic device. The new polydimethylsiloxane (PDMS)-based sprayer was tested with apoferritin. We demonstrate that the structure can be solved to high resolution with this method of sample preparation. Besides replacing the conventional pipetting-blotting-plunging method, one of many potential applications of the new sprayer is in time-resolved cryo-EM, as part of a PDMS-based microfluidic reaction channel to study short-lived intermediates on the timescale of 10-1,000 ms.

  20. Cetirizine dihydrochloride loaded microparticles design using ionotropic cross-linked chitosan nanoparticles by spray-drying method.

    PubMed

    Li, Feng-Qian; Ji, Rui-Rui; Chen, Xu; You, Ben-Ming; Pan, Yong-Hua; Su, Jia-Can

    2010-12-01

    To control the release rate and mask the bitter taste, cetirizine dihydrochloride (CedH) was entrapped within chitosan nanoparticles (CS-NPs) using an ionotropic gelation process, followed by microencapsulation to produce CS matrix microparticles using a spray-drying method. The aqueous colloidal CS-NPs dispersions with a drug encapsulation efficiency (EE) of <15%, were then spray dried to produce a powdered nanoparticles-in-microparticles system with an EE of >70%. The resultant spherical CS microparticles had a smooth surface, were free of organic solvent residue and showed a diameter range of 0.5~5 μm. The in vitro drug release properties of CedH encapsulated microparticles showed an initial burst effect during the first 2 h. Drug release from the matrix CS microparticles could be retarded by the crosslinking agent pentasodium tripolyphosphate or the wall material. The technique of 'ionotropic gelation' combined with 'spray-drying' could be applicable for preparation of CS nanoparticlesin-microparticles drug delivery systems. CS-NPs based microparticles might provide a potential micro-carrier for oral administration of the freely water-soluble drug--CedH.

  1. Non-Destructive Evaluation of Thermal Spray Coating Interface Quality by Eddy Current Method

    SciTech Connect

    B.Mi; X. Zhao; R. Bayles

    2006-05-26

    Thermal spray coating is usually applied through directing molten or softened particles at very high velocities onto a substrate. An eddy current non-destructive inspection technique is presented here for thermal spray coating interface quality characterization. Several high-velocity-oxy-fuel (HVOF) coated steel plates were produced with different surface preparation conditions before applying the coating, e.g., grit-blasted surface, wire-brush cleaned surface, and a dirty surface. A quad-frequency eddy current probe was used to manually scan over the coating surface to evaluate the bonding quality. Experimental results show that the three surface preparation conditions can be successfully differentiated by looking into the impedance difference observed from the eddy current probe. The measurement is fairly robust and consistent. More specimens are also prepared with variations of process parameters, such as spray angle, stand-off distance, and application of corrosion protective sealant, etc. They are blindly tested to evaluate the reliability of the eddy current system. Quantitative relations between the coating bond strength and the eddy current response are also established with the support of destructive testing. This non-contact, non-destructive, easy to use technique has the potential for evaluating the coating quality immediately after its application so that any defects can be corrected immediately.

  2. Kinetic investigation of wood pyrolysis

    SciTech Connect

    Thurner, F.; Mann, U.; Beck, S. R.

    1980-06-01

    The objective of this investigation was to determine the kinetics of the primary reactions of wood pyrolysis. A new experimental method was developed which enabled us to measure the rate of gas, tar, and char production while taking into account the temperature variations during the wood heating up. The experimental method developed did not require any sophisticated instruments. It facilitated the collection of gas, tar and residue (unreacted wood and char) as well as accurate measurement of the temperature inside the wood sample. Expressions relating the kinetic parameters to the measured variables were derived. The pyrolysis kinetics was investigated in the range of 300 to 400/sup 0/C at atmospheric pressure and under nitrogen atmosphere. Reaction temperature and mass fractions of gas, tar, and residue were measured as a function of time. Assuming first-order reactions, the kinetic parameters were determined using differential method. The measured activation energies of wood pyrolysis to gas, tar, and char were 88.6, 112.7, and 106.5 kJ/mole, respectively. These kinetic data were then used to predict the yield of the various pyrolysis products. It was found that the best prediction was obtained when an integral-mean temperature obtained from the temperature-time curve was used as reaction temperature. The pyrolysis products were analyzed to investigate the influence of the pyrolysis conditions on the composition. The gas consisted mainly of carbon dioxide, carbon monoxide, oxygen, and C/sub 3//sup +/-compounds. The gas composition depended on reaction time as well as reactor temperature. The tar analysis indicated that the tar consisted of about seven compounds. Its major compound was believed to be levoglucosan. Elemental analysis for the char showed that the carbon content increased with increasing temperature.

  3. Method and apparatus for pyrolysis--porous layer open tubular column--cryoadsorption headspace sampling and analysis.

    PubMed

    Bruno, Thomas J; Nichols, Jessica E

    2013-04-19

    In previous work, dynamic headspace vapor collection on short, porous layer open tubular (PLOT) capillary columns maintained at low temperature was introduced. In this paper, that metrology is extended with the introduction of a small in situ pyrolysis platform that provides for rapid heating and rapid vapor capture for a wide variety of samples. The new approach is referred to as pyro-PLOT-cryo. The pyrolysis platform is made from two small copper lead wires that hold a basket formed from small diameter, high resistance stainless steel or NiCr wire. The basket is formed to accept a small sample, the mass of which can typically range from 0.2 to 0.05 mg. The pyrolysis is performed by use of a resistor capacitor circuit of the type used in spot welders. We have provided examples of the application of this technique with the analysis of facial cosmetics, plastic explosives, organometallic gasoline additives, polymers, and in micro scale chemical reactions. Additional modifications and future work are also discussed.

  4. Evaluation of phosphorus adsorption capacity of sesame straw biochar on aqueous solution: influence of activation methods and pyrolysis temperatures.

    PubMed

    Park, J H; Ok, Y S; Kim, S H; Cho, J S; Heo, J S; Delaune, R D; Seo, D C

    2015-12-01

    The phosphorus (P) adsorption characteristic of sesame straw biochar prepared with different activation agents and pyrolysis temperatures was evaluated. Between 0.109 and 0.300 mg L(-1) in the form of inorganic phosphate was released from raw sesame straw biochar in the first 1 h. The release of phosphate was significantly enhanced from 62.6 to 168.2 mg g(-1) as the pyrolysis temperature increased. Therefore, sesame straw biochar cannot be used as an adsorbent for P removal without change in the physicochemical characteristics. To increase the P adsorption of biochar in aqueous solution, various activation agents and pyrolysis temperatures were applied. The amount of P adsorbed from aqueous solution by biochar activated using different activation agents appeared in the order ZnCl2 (9.675 mg g(-1)) > MgO (8.669 mg g(-1)) ⋙ 0.1N-HCl > 0.1N-H2SO4 > K2SO4 ≥ KOH ≥ 0.1N-H3PO4, showing ZnCl2 to be the optimum activation agent. Higher P was adsorbed by the biochar activated using ZnCl2 under different pyrolysis temperatures in the order 600 °C > 500 °C > 400 °C > 300 °C. Finally, the amount of adsorbed P by activated biochar at different ratios of biochar to ZnCl2 appeared in the order 1:3 ≒ 1:1 > 3:1. As a result, the optimum ratio of biochar to ZnCl2 and pyrolysis temperature were found to be 1:1 and 600 °C for P adsorption, respectively. The maximum P adsorption capacity by activated biochar using ZnCl2 (15,460 mg kg(-1)) was higher than that of typical biochar, as determined by the Langmuir adsorption isotherm. Therefore, the ZnCl2 activation of sesame straw biochar was suitable for the preparation of activated biochar for P adsorption.

  5. Scalable synthesis of mesoporous titania microspheres via spray-drying method.

    PubMed

    Pal, Manas; Wan, Li; Zhu, Yongheng; Liu, Yupu; Liu, Yang; Gao, Wenjun; Li, Yuhui; Zheng, Gengfeng; Elzatahry, Ahmed A; Alghamdi, Abdulaziz; Deng, Yonghui; Zhao, Dongyuan

    2016-10-01

    Mesoporous TiO2 has several potential applications due to its unique electronic and optical properties, although its structures and morphologies are typically difficult to tune because of its uncontrollable and fast sol-gel reaction. In this study we have coupled the template-directed-sol-gel-chemistry with the low-cost, scalable, and environmentally benign aerosol (spray-drying) one-pot preparation technique for the fabrication of hierarchically mesoporous TiO2 microspheres and Fe3O4@mesoporous TiO2-x microspheres in a large scale. Parameters during the pre-hydrolysis and spray-drying treatment were varied to successfully control the bead diameter, morphology, monodispersity, surface area and pore size for improving their effectiveness for better application. Unlike to the previous aerosol synthetic approaches, where mainly quite a high temperature gradient with the strict control of spray-drying precursor concentration is implied, our strategy is lying on comparatively low drying temperature with an additional post-ultrasonication (further hydrolysis and condensation) route of the pre-calcined TiO2 samples. As-synthesized mesoporous microspheres have a size distribution from 500nm to 5μm, specific surface areas ranging from 150 to 162m(2)g(-1) and mean pore sizes of several nanometers (4-6nm). Further Fe3O4@mesoporous TiO2-x microspheres were observed to show remarkable selective phosphopeptide-enrichment activity which might have significant importance in disease diagnosis and other biomedical applications.

  6. Thermal Arc Spray Overview

    NASA Astrophysics Data System (ADS)

    Hafiz Abd Malek, Muhamad; Hayati Saad, Nor; Kiyai Abas, Sunhaji; Mohd Shah, Noriyati

    2013-06-01

    Usage of protective coating for corrosion protection was on highly demand during the past decade; and thermal spray coating played a major part during that time. In recent years, the thermal arc spray coating becomes a popular coating. Many big players in oil and gas such as PETRONAS, EXXON MOBIL and SHELL in Malaysia tend to use the coating on steel structure as a corrosion protection. Further developments in coating processes, the devices, and raw materials have led to expansion of functional coatings and applications scope from conventional coating to specialized industries. It is widely used because of its ability to withstand high process temperature, offer advantages in efficiency, lower cost and acts as a corrosion protection. Previous research also indicated that the thermal arc spray offers better coating properties compared to other methods of spray. This paper reviews some critical area of thermal spray coating by discussing the process/parameter of thermal arc spray technology and quality control of coating. Coating performance against corrosion, wear and special characteristic of coating are also described. The field application of arc spray technology are demonstrated and reviewed.

  7. Method of forming a plasma sprayed interconnection layer on an electrode of an electrochemical cell

    DOEpatents

    Spengler, C.J.; Folser, G.R.; Vora, S.D.; Kuo, L.; Richards, V.L.

    1995-06-20

    A dense, substantially gas-tight, electrically conductive interconnection layer is formed on an air electrode structure of an electrochemical cell by (A) providing an electrode surface; (B) forming on a selected portion of the electrode surface, a layer of doped LaCrO{sub 3} particles doped with an element selected from Ca, Sr, Ba, Mg, Co, Ni, Al and mixtures thereof by plasma spraying doped LaCrO{sub 3} powder, preferably compensated with chromium as Cr{sub 2}O{sub 3} and/or dopant element, preferably by plasma arc spraying; and, (C) heating the doped and compensated LaCrO{sub 3} layer to about 1100 C to 1300 C to provide a dense, substantially gas-tight, substantially hydration-free, electrically conductive interconnection material bonded to the electrode surface. A solid electrolyte layer can be applied to the unselected portion of the air electrode, and a fuel electrode can be applied to the solid electrolyte, to provide an electrochemical cell. 6 figs.

  8. Fabrication of microporous polyurethane by spray phase inversion method as small diameter vascular grafts material.

    PubMed

    Khorasani, M T; Shorgashti, S

    2006-05-01

    Microporous polyurethane vascular prostheses with a 4 mm diameter and 0.3-0.4 mm wall thickness were fabricated by a spray phase inversion technique. In this study, the effect of distance between spray guns (SG) and rotating mandrel (RM), the effect of rate of rotating mandrel (RRM), and the type of nonsolvent on pore morphology of PU films were evaluated using scanning electron microscopy (SEM) technique. It was observed that when the distance between SG and RM was increased or the rate of RM was decreased, the porosity of PU films increased and consequently the tensile strength decreased and compliance value increased. Compliance was measured in vitro by volume and vessel diameter changes. Furthermore, when the coagulant (water) was changed to the water/methanol, the porosity of PU film increased and porous morphology changed to filamentous morphology. Attachment of anchorage dependent cells, namely L929 fibroblast cells, were investigated in stationary culture conditions. The cells adhesion and cells growth were studied using optical photomicrographs. The results show that by increasing the porosity content of PU films would consequently increase the cell ingrowths.

  9. Method of forming a plasma sprayed interconnection layer on an electrode of an electrochemical cell

    DOEpatents

    Spengler, Charles J.; Folser, George R.; Vora, Shailesh D.; Kuo, Lewis; Richards, Von L.

    1995-01-01

    A dense, substantially gas-tight, electrically conductive interconnection layer is formed on an air electrode structure of an electrochemical cell by (A) providing an electrode surface; (B) forming on a selected portion of the electrode surface, a layer of doped LaCrO.sub.3 particles doped with an element selected from Ca, Sr, Ba, Mg, Co, Ni, Al and mixtures thereof by plasma spraying doped LaCrO.sub.3 powder, preferably compensated with chromium as Cr.sub.2 O.sub.3 and/or dopant element, preferably by plasma arc spraying; and, (C) heating the doped and compensated LaCrO.sub.3 layer to about 1100.degree. C. to 1300.degree. C. to provide a dense, substantially gas-tight, substantially hydration-free, electrically conductive interconnection material bonded to the electrode surface. A solid electrolyte layer can be applied to the unselected portion of the air electrode, and a fuel electrode can be applied to the solid electrolyte, to provide an electrochemical cell.

  10. Optimisation of a vertical spray boom for greenhouse spraying applications.

    PubMed

    Nuyttens, D; Windey, S; Braekman, P; De Moor, A; Sonck, B

    2003-01-01

    The European Crop Protection Association (ECPA) and CLO-DVL joined forces in a project to stimulate a safe use of pesticides in Southern European countries. CLO-DVL optimised a method with mineral chelates to evaluate deposition tests. This quantitative method to evaluate spray deposits and to check spray distributions is used to assess two novel spraying techniques. Deposition tests with water-sensitive paper and mainly with the manganese and molybdenum chelates as tracer elements were performed with a manually pulled trolley and a motorised vehicle both equipped with vertical spray booms. Filter papers were attached to the tomato and pepper plants at several heights to obtain an indication of the spray distribution in the crop. Particular attention was paid to the effect on the spray distribution of the vertical nozzle distance (35 cm vs. 50 cm) and the spray distance to the crop. The tests proved that a nozzle spacing of 35 cm delivers a much better spray distribution than one of 50 cm. The optimal spray distance for flat fan nozzles with a spray angle of 80 degrees and a nozzle spacing of 35 cm is about 30 cm.

  11. Spray atomization of bio-oil/ethanol blends with externally mixed nozzles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Experiments were conducted to investigate the properties of sprays of pyrolysis oil from biomass (bio-oil) using an air assisted atomization nozzle operated without combustion to explore the potential of pyrolysis oil combustion in industrial and home furnaces. Bio-oil was blended with ethanol to im...

  12. Method for the determination of lignin content of a sample by flash pyrolysis in an atmosphere of hydrogen or helium and method therefor

    NASA Technical Reports Server (NTRS)

    Shakkottai, Parthasarathy (Inventor); Kwack, Eug Y. (Inventor); Lawson, Daniel D. (Inventor)

    1991-01-01

    The lignin content of wood, paper pulp or other material containing lignin (such as filter paper soaked in black liquor) is more readily determined by flash pyrolysis of the sample at approximately 550.degree. C. in a reducing atmosphere of hydrogen or in an inert atmosphere of helium followed by a rapid analysis of the product gas by a mass spectrometer. The heated pyrolysis unit as fabricated comprises a small platinum cup welded to an electrically-heated stainless steel ribbon with control means for programmed short duration (1.5 sec, approximately) heating and means for continuous flow of hydrogen or helium. The pyrolysis products enter an electron-ionization mode mass spectrometer for spectral evaluation. Lignin content is obtained from certain ratios of integrated ion currents of many mass spectral lines, the ratios being linearly related to the Kappa number of Klason lignin.

  13. Kinetics study on conventional and microwave pyrolysis of moso bamboo.

    PubMed

    Dong, Qing; Xiong, Yuanquan

    2014-11-01

    A comparative study on the pyrolysis kinetics of moso bamboo has been conducted in a conventional thermogravimetric analyzer and a microwave thermogravimetric analyzer respectively. The effect of heating rate on the pyrolysis process was also discussed. The results showed that both the maximum and average reaction rates increased with the heating rate increasing. The values of activation energy increased from 58.30 to 84.22 kJ/mol with the heating rate decreasing from 135 to 60 °C/min during conventional pyrolysis. The value of activation energy was 24.5 kJ/mol for microwave pyrolysis, much lower than that for conventional pyrolysis at a similar heating rate of 160 °C/min. The pyrolysis of moso bamboo exhibited a kinetic compensation effect. The low activation energy obtained under microwave irradiation suggests that microwaves heating would be a promising method for biomass pyrolysis.

  14. Supersonic-Spray Cleaner

    NASA Technical Reports Server (NTRS)

    Caimi, Raoul E. B.; Lin, Feng-Nan; Thaxton, Eric A.

    1995-01-01

    Spraying system for cleaning mechanical components uses less liquid and operates at pressures significantly lower. Liquid currently used is water. Designed to replace chlorofluorocarbon (CFC) solvent-based cleaning and cleanliness verification methods. Consists of spray head containing supersonic converging/diverging nozzles, source of gas at regulated pressure, pressurized liquid tank, and various hoses, fittings, valves, and gauges. Parameters of nozzles set so any of large variety of liquids and gases combined in desired ratio and rate of flow. Size and number of nozzles varied so system built in configurations ranging from small hand-held spray heads to large multinozzle cleaners. Also used to verify part adequately cleaned. Runoff liquid from spray directed at part collected. Liquid analyzed for presence of contaminants, and part recleaned if necessary.

  15. Spray drying method for large-scale and high-performance silicon negative electrodes in Li-ion batteries.

    PubMed

    Jung, Dae Soo; Hwang, Tae Hoon; Park, Seung Bin; Choi, Jang Wook

    2013-05-08

    Nanostructured silicon electrodes have shown great potential as lithium ion battery anodes because they can address capacity fading mechanisms originating from large volume changes of silicon alloys while delivering extraordinarily large gravimetric capacities. Nonetheless, synthesis of well-defined silicon nanostructures in an industrially adaptable scale still remains as a challenge. Herein, we adopt an industrially established spray drying process to enable scalable synthesis of silicon-carbon composite particles in which silicon nanoparticles are embedded in porous carbon particles. The void space existing in the porous carbon accommodates the volume expansion of silicon and thus addresses the chronic fading mechanisms of silicon anodes. The composite electrodes exhibit excellent electrochemical performance, such as 1956 mAh/g at 0.05C rate and 91% capacity retention after 150 cycles. Moreover, the spray drying method requires only 2 s for the formation of each particle and allows a production capability of ~10 g/h even with an ultrasonic-based lab-scale equipment. This investigation suggests that established industrial processes could be adaptable to the production of battery active materials that require sophisticated nanostructures as well as large quantity syntheses.

  16. Fabrication method for photovoltaic materials by chemical atomisation spray. Final report

    SciTech Connect

    Savelli, M.; LaHaye, J.; Vadel, J.

    1982-09-01

    Acetonitrile has been shown to be a suitable carrier solvent for the preparation of thin layers of cuprous sulphide by chemical atomisation. A reactive spraying apparatus for monodispersed mist has been developed. It is claimed to be indispensible for establishing a firm relation between the characteristics of the mist and those of the films obtained. The formation of thin layers of cadmium sulphide and stannic oxide on various supports has been studied and the quality of the layers, their adhesion to the support, and the influence of the nature and temperature of the support on the reactions have been investigated. Three laboratories have participated in the evaluation of the physical characteristics of the thin layers.

  17. Fabrication of multifunctional cellulose nanocrystals/poly(lactic acid) nanocomposites with silver nanoparticles by spraying method.

    PubMed

    Yu, Hou-Yong; Yang, Xing-Yuan; Lu, Fang-Fang; Chen, Guo-Yin; Yao, Ju-Ming

    2016-04-20

    The poly (lactic acid) (PLA)/functionalized cellulose nanocrystals formates (CNFs) were prepared by solution casting and then the binary films were sprayed with silver ammonia aqueous solution to fabricate PLA/CNF/Ag ternary nanocomposites. It was found that both deposited silver (Ag) nanoparticles and CNFs showed efficient reinforcing effect on the thermal, mechanical, barrier properties and antibacterial activity of PLA matrix. Especially, the maximum decomposition temperature (Tmax) and Young's modulus of PLA/CNF/Ag(6) nanocomposite film increased by 15.5°C and 48.7%, respectively. Meanwhile an obvious reduction in the water vapor permeability was detected. Furthermore, the migration levels of the ternary nanocomposite films were well below the permitted limits in both non-polar and polar food simulants (60mgkg(-1)), and they showed a significant antibacterial activity influenced by the Ag contents. This study reveals that the novel nanocomposite films will offer a good perspective for food packaging applications.

  18. High drug load, stable, manufacturable and bioavailable fenofibrate formulations in mesoporous silica: a comparison of spray drying versus solvent impregnation methods.

    PubMed

    Hong, Shiqi; Shen, Shoucang; Tan, David Cheng Thiam; Ng, Wai Kiong; Liu, Xueming; Chia, Leonard S O; Irwan, Anastasia W; Tan, Reginald; Nowak, Steven A; Marsh, Kennan; Gokhale, Rajeev

    2016-01-01

    Encapsulation of drugs in mesoporous silica using co-spray drying process has been recently explored as potential industrial method. However, the impact of spray drying on manufacturability, physiochemical stability and bioavailability in relation to conventional drug load processes are yet to be fully investigated. Using a 2(3) factorial design, this study aims to investigate the effect of drug-loading process (co-spray drying and solvent impregnation), mesoporous silica pore size (SBA-15, 6.5 nm and MCM-41, 2.5 nm) and percentage drug load (30% w/w and 50% w/w) on material properties, crystallinity, physicochemical stability, release profiles and bioavailability of fenofibrate (FEN) loaded into mesoporous silica. From the scanning electronic microscopy (SEM) images, powder X-ray diffraction and Differential scanning calorimetry measurements, it is indicated that the co-spray drying process was able to load up to 50% (w/w) FEN in amorphous form onto the mesoporous silica as compared to the 30% (w/w) for solvent impregnation. The in vitro dissolution rate of the co-spray dried formulations was also significantly (p = 0.044) better than solvent impregnated formulations at the same drug loading. Six-month accelerated stability test at 40 °C/75 RH in open dish indicated excellent physical and chemical stability of formulations prepared by both methods. The amorphous state of FEN and the enhanced dissolution profiles were well preserved, and very low levels of degradation were detected after storage. The dog data for the three selected co-spray-dried formulations revealed multiple fold increment in FEN bioavailability compared to the reference crystalline FEN. These results validate the viability of co-spray-dried mesoporous silica formulations with high amorphous drug load as potential drug delivery systems for poorly water soluble drugs.

  19. The use of anthracene as a model compound in a comparative study of hydrous pyrolysis methods for industrial waste remediation.

    PubMed

    Nkansah, Marian Asantewah; Christy, Alfred A; Barth, Tanja

    2011-07-01

    Polycyclic aromatic hydrocarbons are very stable compounds and tend to bioaccumulate in the environment due to their high degree of conjugation and aromaticity. Hydrous pyrolysis is explored as a technique for the treatment of industrial water containing PAH, using anthracene as a model compound. The reactivity of anthracene under a range of temperatures and durations are studied in this paper. Aliquots of 1.0-10.0mg of anthracene in a range of 1.0-5.0 mL of H(2)O are subjected to hydrous pyrolysis under varied conditions of temperature, reagents and duration. The conditions include oxidising systems comprising distilled water, hydrogen peroxide and Nafion-SiO(2) solid catalyst in water; and reducing systems of formic acid and formic acid/Nafion-SiO(2)/Pd-C catalysts to assess a range of redox reaction conditions. Oxygen in air played a role in some of the reaction conditions. Pyrolysed products were identified and quantified by the use of Gas Chromatography-Mass Spectrometry (GC-MS). The major products were anthrone, anthraquinone, xanthone from oxidation; and multiple hydro-anthracene derivatives from reductive hydogenation. The nature of reaction conditions influenced the extent of anthracene degradation. The products formed are more reactive (less stable) as compared to anthracene the starting material and will therefore be less persistent in the environment.

  20. Fundamental Pyrolysis Studies

    SciTech Connect

    Milne, T. A.; Evans, R. J.; Soltys, M. N.

    1983-03-01

    Progress on the direct mass spectrometric sampling of pyrolysis products from wood and its constituents is described for the period from June 1982 to February 1983. A brief summary and references to detailed reports, of the qualitative demonstration of our approach to the study of the separated processes of primary and secondary pyrolysis is presented. Improvements and additions to the pyrolysis and data acquisition systems are discussed and typical results shown. Chief of these are a heated-grid pyrolysis system for controlled primary pyrolysis and a sheathed flame arrangement for secondary cracking studies. Qualitative results of the secondary cracking of cellulose, lignin, and wood are shown as are comparisons with the literature for the pyrolysis spectra of cellulose, lignin, and levoglucosan. 'Fingerprints' for a number of materials are shown, with spectra taken under carefully controlled conditions so that sensitivity calibrations for different compounds, now being determined, can be applied.

  1. Carbon nanoscrolls by pyrolysis of a polymer

    NASA Astrophysics Data System (ADS)

    Yadav, Prasad; Warule, Sambhaji; Jog, Jyoti; Ogale, Satishchandra

    2012-12-01

    3D network of carbon nanoscrolls was synthesized starting from pyrolysis of poly(acrylic acid-co-maleic acid) sodium salt. It is a catalyst-free process where pyrolysis of polymer leads to formation of carbon form and sodium carbonate. Upon water soaking of pyrolysis product, the carbon form undergoes self-assembly to form carbon nanoscrolls. The interlayer distance between the walls of carbon nanoscroll was found to be 0.34 nm and the carbon nanoscrolls exhibited a surface area of 188 m2/g as measured by the BET method.

  2. Supercritical Fuel Pyrolysis

    DTIC Science & Technology

    2010-05-30

    experiments are conducted in the isothermal , isobaric reactor designed expressly for such purposes by Davis [22] and used by Stewart [11,12] in the AFOSR... isothermal , isobaric reactor specially designed for such purposes, we have conducted supercritical pyrolysis experiments with three model fuels: 1...prevalent understanding of how these different component groups behave under pyrolysis conditions. Clearly we need to know more about the pyrolysis

  3. Bulk heterojunction thin film formation by single and dual feed ultrasonic spray method for application in organic solar cells

    NASA Astrophysics Data System (ADS)

    Marathe, D. M.; Tarkas, H. S.; Mahajan, M. S.; Lonkar, G. S.; Tak, S. R.; Sali, J. V.

    2016-09-01

    We here present a way of preparing the polymer: fullerene BHJ using dual feed method which can lead to formation of pure phases. In this report, we present results of our initial experiments in this direction. The effect of process parameters on the thickness and surface roughness of the active layer has been discussed. The structural and optical properties have been studied using the optical microscope, UV—visible spectroscopy and photoluminescence spectroscopy. Significant PL quenching indicates efficient charge separation in the BHJ formed using this technique. We have also compared the BHJ thin films prepared with this dual feed ultrasonic technique with the single feed spray method. The BHJ formed using this technique has been used as an active layer in OSC. supported by the University Grants Commission, New Delhi, under Faculty Improvement Programme (No. 33-02/12(WRO) Dt.19.03.2013) and the Special Assistance Programme (530/2/DRS/2010(SAP-I)) Phase-II.

  4. Taste-masking effect of physical and organoleptic methods on peppermint-scented orally disintegrating tablet of famotidine based on suspension spray-coating method.

    PubMed

    Sugiura, Takeshi; Uchida, Shinya; Namiki, Noriyuki

    2012-01-01

    Orally disintegrating tablets (ODTs) are useful for improving benefits for patients of various ages. Masking the unpleasant taste of a drug is an important factor in the compliance of patients who take ODTs. We evaluated the taste acceptability effects of various taste-masking methods on bitter famotidine ODTs as a clinical pharmacological study. The following methods were tested to compare taste-masking effects: physical masking by spray-coating famotidine with ethyl cellulose versus organoleptic masking with added sweetener and flavor. The ODT samples were prepared as single or combinations of each taste-masking method using a novel suspension spray-coating method including a placebo. A total of 31 healthy volunteers were enrolled in this randomized, double-blind study and asked to score their bitterness, sweetness and total palate impressions by 100 mm visual analogue scale (VAS). VAS scores were significantly improved by the physical and organoleptic methods as compared to without taste-masked ODTs. Furthermore, the combination of both taste-masking methods was most effective for improving palatability and VAS scores were similar to those of placebo ODTs. The results of this study suggest that different taste-masking mechanisms function cooperatively.

  5. 10 CFR 431.264 - Uniform test method for the measurement of flow rate for commercial prerinse spray valves.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Commercial Prerinse Spray... resolution of the test instrumentation. Round off calculations to the same number of significant digits...

  6. 10 CFR 431.264 - Uniform test method for the measurement of flow rate for commercial prerinse spray valves.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Commercial Prerinse Spray... resolution of the test instrumentation. Round off calculations to the same number of significant digits...

  7. Review of NMR characterization of pyrolysis oils

    SciTech Connect

    Hao, Naijia; Ben, Haoxi; Yoo, Chang Geun; Adhikari, Sushil; Ragauskas, Arthur J.

    2016-08-24

    Here, pyrolysis of renewable biomass has been developed as a method to produce green fuels and chemicals in response to energy security concerns as well as to alleviate environmental issues incurred with fossil fuel usage. However, pyrolysis oils still have limited commercial application, mainly because unprocessed oils cannot be readily blended with current petroleum-based transportation fuels. To better understand these challenges, researchers have applied diverse characterization techniques in the development of bio-oil studies. In particular, nuclear magnetic resonance (NMR) is a key spectroscopic characterization method through analysis of bio-oil components. This review highlights the NMR strategies for pyrolysis oil characterization and critically discusses the applications of 1H, 13C, 31P, 19F, and two-dimensional (2-D NMR) analyses such as heteronuclear single quantum correlation (HSQC) in representative pyrolysis oil studies.

  8. Review of NMR characterization of pyrolysis oils

    DOE PAGES

    Hao, Naijia; Ben, Haoxi; Yoo, Chang Geun; ...

    2016-08-24

    Here, pyrolysis of renewable biomass has been developed as a method to produce green fuels and chemicals in response to energy security concerns as well as to alleviate environmental issues incurred with fossil fuel usage. However, pyrolysis oils still have limited commercial application, mainly because unprocessed oils cannot be readily blended with current petroleum-based transportation fuels. To better understand these challenges, researchers have applied diverse characterization techniques in the development of bio-oil studies. In particular, nuclear magnetic resonance (NMR) is a key spectroscopic characterization method through analysis of bio-oil components. This review highlights the NMR strategies for pyrolysis oil characterizationmore » and critically discusses the applications of 1H, 13C, 31P, 19F, and two-dimensional (2-D NMR) analyses such as heteronuclear single quantum correlation (HSQC) in representative pyrolysis oil studies.« less

  9. Method of making supercritical fluid molecular spray films, powder and fibers

    DOEpatents

    Smith, Richard D.

    1988-01-01

    Solid films are deposited, or fine powders formed, by dissolving a solid material into a supercritical fluid solution at an elevated pressure and then rapidly expanding the solution through a heated nozzle having a short orifice into a region of relatively low pressure. This produces a molecular spray which is directed against a substrate to deposit a solid thin film thereon, or discharged into a collection chamber to collect a fine powder. In another embodiment, the temperature of the solution and nozzle is elevated above the melting point of the solute, which is preferably a polymer, and the solution is maintained at a pressure such that, during expansion, the solute precipitates out of solution within the nozzle in a liquid state. Alternatively, a secondary solvent mutually soluble with the solute and primary solvent and having a higher critical temperature than that of primary solvent is used in a low concentration (<20%) to maintain the solute in a transient liquid state. The solute is discharged in the form of long, thin fibers. The fibers are collected at sufficient distance from the orifice to allow them to solidify in the low pressure/temperature region.

  10. Zone heating for fluidized bed silane pyrolysis

    NASA Technical Reports Server (NTRS)

    Iya, Sridhar K. (Inventor)

    1987-01-01

    An improved heated fluidized bed reactor and method for the production of high purity polycrystalline silicon by silane pyrolysis wherein silicon seed particles are heated in an upper heating zone of the reactor and admixed with particles in a lower reaction zone, in which zone a silane-containing gas stream, having passed through a lower cooled gas distribution zone not conducive to silane pyrolysis, contacts the heated seed particles whereon the silane is heterogeneously reduced to silicon.

  11. Preparation and Characterization of the Solid Spherical HMX/F2602 by the Suspension Spray-Drying Method

    NASA Astrophysics Data System (ADS)

    Ji, Wei; Li, Xiaodong; Wang, Jingyu; Ye, Baoyun; Wang, Cailing

    2016-10-01

    Solid spherical octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine/fluororubber2602 (HMX/F2602) was prepared by the suspension spray-drying method as follows: firstly, thinning octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) was obtained by a solvent-anti-solvent method. Secondly, thinning HMX suspended in ethyl acetate solvent in a solution of a binder-F2602-was made into a suspension. Finally, the samples were prepared by spray drying. The samples were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectrometry (XPS), X-ray diffraction (XRD), and Fourier transform infrared (FTIR), and its thermal stability as well as mechanical and spark sensitivities were measured. The results of SEM showed that the grain of HMX/F2602 was solid spherical and the particle distribution was homogeneous. The results of XPS indicated that F2602 can be successfully coated on the surface of HMX crystals. Compared to raw HMX, th characteristic drop height was increased from 19.60 to 40.37 cm, an increase of 79.10%. The friction sensitivities of HMX reduced from 100 to 28% and the spark sensitivity of HMX/F2602 increased. The critical explosion temperatures of raw HMX and HMX/F2602 were 275.43 and 274.30°C, respectively. The amount of gas evolution of raw HMX and HMX/F2602 was 0.15 and 0.12 ml.(5 g)-1, respectively. The results of DSC and vacuum stability tests (VSTs) indicate that the thermal stability of HMX/F2602 was equal to that of raw HMX and HMX and F2602 had good compatibility.

  12. Vacuum Plasma Spraying Replaces Electrodeposition

    NASA Technical Reports Server (NTRS)

    Holmes, Richard R.; Power, Chris; Burns, David H.; Daniel, Ron; Mckechnie, Timothy N.

    1992-01-01

    Vacuum plasma spraying used to fabricate large parts with complicated contours and inner structures, without uninspectable welds. Reduces time, and expense of fabrication. Wall of combustion chamber built up inside of outer nickel-alloy jacket by plasma spraying. Particles of metal sprayed partially melted in plasma gun and thrown at supersonic speed toward deposition surface. Vacuum plasma-spray produces stronger bond between the grooves and covering layer completing channels and wall of combustion chamber. In tests, bond withstood pressure of 20 kpsi, three times allowable limit by old method.

  13. Pyrolysis system evaluation study

    NASA Technical Reports Server (NTRS)

    1974-01-01

    An evaluation of two different pyrolysis concepts which recover energy from solid waste was conducted in order to determine the merits of each concept for integration into a Integrated Utility System (IUS). The two concepts evaluated were a Lead Bath Furnace Pyrolysis System and a Slagging Vertical Shaft, Partial Air Oxidation Pyrolysis System. Both concepts will produce a fuel gas from the IUS waste and sewage sludge which can be used to offset primary fuel consumption in addition to the sanitary disposal of the waste. The study evaluated the thermal integration of each concept as well as the economic impact on the IUS resulting from integrating each pyrolysis concepts. For reference, the pyrolysis concepts were also compared to incineration which was considered the baseline IUS solid waste disposal system.

  14. Catalytic pyrolysis of wheat bran for hydrocarbons production in the presence of zeolites and noble-metals by using TGA-FTIR method.

    PubMed

    Lazdovica, K; Liepina, L; Kampars, V

    2016-05-01

    Pyrolysis of wheat bran with or without catalysts was investigated using TGA-FTIR method in order to determine the influence of zeolite and noble metal catalysts on the evolution profile and relative yield of the volatile compounds. The addition of all catalysts decreased the volatile matter of wheat bran from 76.3% to 75.9%, 73.9%, 73.5%, 69.7% and increased the solid residue from 18.0% to 18.4%, 20.4%, 20.8%, 24.6% under the catalyst of ZSM-5, 5% Pd/C, MCM-41, and 5% Pt/C. Noble-metal catalysts had higher activity for deoxygenation of compounds containing carbonyl, carboxyl, and hydroxyl groups than zeolites. Degradation of nitrogen containing compounds atom proceeded better in presence of zeolites. Noble-metal catalysts promoted formation of aromatics and changed the profiles of evolved compounds whereas zeolites advanced formation of aliphatics and olefins.

  15. Single step spray drying method to develop proliposomes for inhalation: a systematic study based on quality by design approach.

    PubMed

    Patil-Gadhe, Arpana; Pokharkar, Varsha

    2014-04-01

    Quality by Design (QbD) is a systematic approach to develop drug products which includes evaluation of formulation parameters to achieve defined final product quality. In the present study principles of QbD were extended to the preparation, in-vitro and in-vivo performance of rifapentine-loaded proliposomes for pulmonary inhalation where final product needs to comply with specific properties. The rifapentine-loaded proliposomes for the treatment of tuberculosis were prepared in single step by spray drying method and independent variables were optimized using factorial design approach. Contour plots and multiple regression analysis were used to study the effect of selected independent variables on dependent variables. The effect of presence of drug: hydrogenated soya phosphatidylcholine (HSPC) and type of charged lipid in the formulation at three levels were studied on mass median diameter (MMD), liposomal vesicle size, % encapsulation efficiency (% EE), mass median aerodynamic diameter (MMAD) and fine particle fraction (FPF) as critical quality attributes. Optimized formulation (R-LDPI-7) with drug: HSPC ratio of 1:2 and stearyl amine as charged lipid were found to give respirable proliposomes with MMAD of 1.56 ± 0.16 μm and FPF of 92.5 ± 1.5%. Sustained drug release with Higuchi diffusion kinetics was achieved from liposomally encapsulated rifapentine. Pulmonary pharmacokinetics of optimized batch R-LDPI-7 revealed longer retention of drug in lungs with 7 fold increase in both, the mean residence time and t1/2 as compared to R-DPI-0. The study results demonstrated the application of QbD principles and design of experiment (DOE) approach to develop drug encapsulated proliposomes for inhalation by spray drying in single step.

  16. Simulations of Spray Reacting Flows in a Single Element LDI Injector With and Without Invoking an Eulerian Scalar PDF Method

    NASA Technical Reports Server (NTRS)

    Shih, Tsan-Hsing; Liu, Nan-Suey

    2012-01-01

    This paper presents the numerical simulations of the Jet-A spray reacting flow in a single element lean direct injection (LDI) injector by using the National Combustion Code (NCC) with and without invoking the Eulerian scalar probability density function (PDF) method. The flow field is calculated by using the Reynolds averaged Navier-Stokes equations (RANS and URANS) with nonlinear turbulence models, and when the scalar PDF method is invoked, the energy and compositions or species mass fractions are calculated by solving the equation of an ensemble averaged density-weighted fine-grained probability density function that is referred to here as the averaged probability density function (APDF). A nonlinear model for closing the convection term of the scalar APDF equation is used in the presented simulations and will be briefly described. Detailed comparisons between the results and available experimental data are carried out. Some positive findings of invoking the Eulerian scalar PDF method in both improving the simulation quality and reducing the computing cost are observed.

  17. Pyrolysis with staged recovery

    DOEpatents

    Green, Norman W.; Duraiswamy, Kandaswamy; Lumpkin, Robert E.; Winter, Bruce L.

    1979-03-20

    In a continuous process for recovery of values contained in a solid carbonaceous material, the carbonaceous material is comminuted and then subjected to flash pyrolysis in the presence of a particulate heat source fed over an overflow weir to form a pyrolysis product stream containing a carbon containing solid residue and volatilized hydrocarbons. After the carbon containing solid residue is separated from the pyrolysis product stream, values are obtained by condensing volatilized hydrocarbons. The particulate source of heat is formed by oxidizing carbon in the solid residue.

  18. Pyrolysis with cyclone burner

    DOEpatents

    Green, Norman W.; Duraiswamy, Kandaswamy; Lumpkin, Robert E.

    1978-07-25

    In a continuous process for recovery of values contained in a solid carbonaceous material, the carbonaceous material is comminuted and then subjected to flash pyrolysis in the presence of a particulate heat source over an overflow weir to form a pyrolysis product stream containing a carbon containing solid residue and volatilized hydrocarbons. After the carbon containing solid residue is separated from the pyrolysis product stream, values are obtained by condensing volatilized hydrocarbons. The particulate source of heat is formed by oxidizing carbon in the solid residue and separating out the fines.

  19. Method for producing an object on which an exterior layer is applied by thermal spraying and object, in particular a drill bit, obtained pursuant to this method

    SciTech Connect

    Van Nederveen, H.B.; Verburgh, M.B.

    1984-06-19

    A method is described for producing articles having a metal core, an intermediate powder metallurgy layer, and an exterior wear- and chip-resistant layer on the portions thereof requiring the same, which comprises: applying to a bearing metal core, powdered steel alloy containing about 3.5% nickel by weight by cold isostatic compaction in a compressible mold under a pressure of about 6000 atmospheres to provide an intermediate powder metallurgical layer having a density of about 90%; sintering said intermediate layer on said core in an atmosphere of hydrogen at about 1200/sup 0/ C. for about one hour; applying a wear- and chip-resistant layer to selected portions of said sintered intermediate powder metallurgical layer by plasma spraying; and hot isostatically compacting the sprayed article in a thin-walled deep-drawn vessel of low carbon steel having a wall thickness of about 0.5 mm in which the article to be compacted is surrounded by ceramic powder under a pressure of about 1600 atmospheres at a temperature of about 1100/sup 0/ C. for about two hours, to achieve a firm bond between said intermediate layer and said wear- and chip-resistant layer, and a composite density for said layers of about 99%.

  20. Catalytic pyrolysis-GC/MS of lignin from several sources

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lignin from four different sources extracted by various methods were pyrolyzed at 650 degree C using analytical pyrolysis methods, py-GC/MS. Pyrolysis was carried out in the absence and presence of two heterogeneous catalysts , an acidic zeolite (HZSM-5) catalyst and a mixed metal oxide catalyst (Co...

  1. A New Quantitative 3D Imaging Method for Characterizing Spray in the Near-field of Nozzle Exits

    DTIC Science & Technology

    2015-01-13

    flow system on spray distribution 2. To measure and validate mass distribution of spray ( iodinated contrast) generated by a scaled nozzle...and the present values for the two atomizers. Using the dimensional geometrical parameters, liq- uid properties of the iodine -based solution, and the...commonly used to improve the image quality and dynamic range of X-ray based measurements. In medical diagnostics, iodine is typically used as a

  2. Effect of Sprayed Solution Volume on Physical Properties of Titanium Dioxide Thin Films

    NASA Astrophysics Data System (ADS)

    Naffouti, Wafa; Ben Nasr, Tarek; Briot, Olivier; Kamoun-Turki, Najoua

    2015-10-01

    Titanium dioxide (TiO2) thin films were deposited on glass substrates by spray pyrolysis technique from different solution volumes. We studied the effect of sprayed solution volume on the structural, morphological and optical properties of TiO2 films. X-ray diffraction studies revealed the presence of an anatase phase with a tetragonal structure with (101) preferred orientation. The best crystallinity was obtained in the case of a sprayed solution volume of 60 ml. Also, this film had a lower average surface roughness (RMS) as measured by atomic force microscopy. Transmission and reflection optical analysis showed interference phenomena indicating a smooth reflecting surface of the film. An indirect band gap of about 3.46 eV was found, indicating a potential use of these films in solar cell devices. Based on the optical measurements, the film thickness was determined by the envelope method, which was in agreement with the scanning electron microscopy result. Wemple-Di Domenico single oscillator and Spitzer-Fan models were used to study the optical constants of the films grown from different sprayed solution volumes. Photoluminescence emission intensity was found to increase with increasing film crystallinity, and the spectra showed ultraviolet and visible emissions corresponding to intrinsic emission and trap levels within the band gap, respectively.

  3. Substrate system for spray forming

    DOEpatents

    Chu, Men G.; Chernicoff, William P.

    2002-01-01

    A substrate system for receiving a deposit of sprayed metal droplets including a movable outer substrate on which the sprayed metal droplets are deposited. The substrate system also includes an inner substrate disposed adjacent the outer substrate where the sprayed metal droplets are deposited on the outer substrate. The inner substrate includes zones of differing thermal conductivity to resist substrate layer porosity and to resist formation of large grains and coarse constituent particles in a bulk layer of the metal droplets which have accumulated on the outer substrate. A spray forming apparatus and associated method of spray forming a molten metal to form a metal product using the substrate system of the invention is also provided.

  4. Substrate system for spray forming

    DOEpatents

    Chu, Men G.; Chernicoff, William P.

    2000-01-01

    A substrate system for receiving a deposit of sprayed metal droplets including a movable outer substrate on which the sprayed metal droplets are deposited. The substrate system also includes an inner substrate disposed adjacent the outer substrate where the sprayed metal droplets are deposited on the outer substrate. The inner substrate includes zones of differing thermal conductivity to resist substrate layer porosity and to resist formation of large grains and coarse constituent particles in a bulk layer of the metal droplets which have accumulated on the outer substrate. A spray forming apparatus and associated method of spray forming a molten metal to form a metal product using the substrate system of the invention is also provided.

  5. Boron liquid solution deposited by spray method for p-type emitter formation in crystalline Si solar cells

    NASA Astrophysics Data System (ADS)

    Panek, Piotr; Swatowska, Barbara; Dawidowski, Wojciech; Juel, Mari; Zieba, Paweł

    2016-12-01

    This paper reports the fabrication of n-type crystalline Si based solar cell using boron liquid solution (BLS) deposited by spray method for p-type emitter formation. The X-ray photoelectron spectroscopy (XPS) was used for the analysis of surface composition and electronic states of elements at the glass layer of dopant (GLD) obtained from BLS. The investigation of the borosilicate glass layer (BSG) created on a base of GLD during diffusion process were carried out by transmission electron microscopy (TEM). The diffusion profiles were determined by secondary ion mass spectrometry (SIMS) and electrochemical capacitance-voltage (EC-V) techniques, whereas the solar cells were characterized by the light current-voltage (I-V) and spectral measurements. The influence of a doping process on a minority carrier lifetime of the Si wafers was detected by quasi-steady-state photoconductance technique. Application of the elaborated BSL allowed to obtain the p-type Si emitters from BSG layer which exhibits unproblematic etching behaviour after diffusion process and final fabrication of the solar cells with the fill factor of 74% and photoconversion efficiency of 13.04 %. The elaborated BLS is a source which offers an attractive practicable alternative to form emitters on the n-type Si substrate.

  6. Annealing-free, flexible silver nanowire-polymer composite electrodes via a continuous two-step spray-coating method.

    PubMed

    Choi, Dong Yun; Kang, Hyun Wook; Sung, Hyung Jin; Kim, Sang Soo

    2013-02-07

    For the realization of high-efficiency flexible optoelectronic devices, transparent electrodes should be fabricated through a low-temperature process and have the crucial feature of low surface roughness. In this paper, we demonstrated a two-step spray-coating method for producing large-scale, smooth and flexible silver nanowire (AgNW)-poly3,4-ethylenedioxythiophene:polystyrenesulfonate (PEDOT:PSS) composite electrodes. Without the high-temperature annealing process, the conductivity of the composite film was improved via the lamination of highly conductive PEDOT:PSS modified by dimethyl sulfoxide (DMSO). Under the room temperature process condition, we fabricated the AgNW-PEDOT:PSS composite film showing an 84.3% mean optical transmittance with a 10.76 Ω sq(-1) sheet resistance. The figure of merit Φ(TC) was higher than that obtained from the indium tin oxide (ITO) films. The sheet resistance of the composite film slightly increased less than 5.3% during 200 cycles of tensile and compression folding, displaying good electromechanical flexibility for use in flexible optoelectronic applications.

  7. Linear-Source Ultrasonic Spray Chemical Vapor Deposition Method for Fabrication of ZnMgO Films and Ultraviolet Photodetectors

    NASA Astrophysics Data System (ADS)

    Kamada, Yudai; Kawaharamura, Toshiyuki; Nishinaka, Hiroyuki; Fujita, Shizuo

    2006-08-01

    A linear-source ultrasonic spray chemical vapor deposition method has been developed and applied to fabricate ZnMgO ternary alloy thin films on glass substrates. A water solution of zinc acetate and magnesium acetate was ultrasonically atomized to form aerosol particles of water containing the sources, and then they were supplied onto the heated substrate by a nitrogen carrier gas through a nozzle with a linear aperture to form ZnMgO films. The source concentration ratios in the water solution successfully controlled the solid composition and hence raised the band gap of ZnMgO up to 3.75 eV, keeping the optical transmission higher than 90% for the visible-light region. An UV photodetector fabricated using the ZnMgO film showed the photoresponsivity to be as high as a few A/W, suggesting that this simple and cost-effective technique is promising for fabricating ZnMgO films for various applications.

  8. Relationship between hydrous and ordinary pyrolysis

    SciTech Connect

    Burnham, A.K.

    1993-06-01

    Pyrolysis results are reviewed briefly with the intent of drawing comparisons between open, high pressure, and hydrous pyrolysis. Empirically, the degree of pyrolysis severity to form volatile products in open pyrolysis is similar to that required to form an expelled oil phase in hydrous pyrolysis. The yields of hydrocarbons from open pyrolysis are close to those from hydrous pyrolysis, but hydrous pyrolysis tends to assist the separation of hydrocarbons from polar materials. Pressure has a small but measurable affect on the generation kinetics.

  9. Development of method to characterize emissions from spray polyurethane foam insulation

    EPA Science Inventory

    This presentation updates symposium participants re EPA progress towards development of SPF insulation emissions characterization methods. The presentation highlights evaluation of experiments investigating emissions after application of SPF to substrates in micro chambers and i...

  10. Stabilization of Fast Pyrolysis Oil: Post Processing Final Report

    SciTech Connect

    Elliott, Douglas C.; Lee, Suh-Jane; Hart, Todd R.

    2012-03-01

    UOP LLC, a Honeywell Company, assembled a comprehensive team for a two-year project to demonstrate innovative methods for the stabilization of pyrolysis oil in accordance with DOE Funding Opportunity Announcement (FOA) DE-PS36-08GO98018, Biomass Fast Pyrolysis Oil (Bio-oil) Stabilization. In collaboration with NREL, PNNL, the USDA Agricultural Research Service (ARS), Pall Fuels and Chemicals, and Ensyn Corporation, UOP developed solutions to the key technical challenges outlined in the FOA. The UOP team proposed a multi-track technical approach for pyrolysis oil stabilization. Conceptually, methods for pyrolysis oil stabilization can be employed during one or both of two stages: (1) during the pyrolysis process (In Process); or (2) after condensation of the resulting vapor (Post-Process). Stabilization methods fall into two distinct classes: those that modify the chemical composition of the pyrolysis oil, making it less reactive; and those that remove destabilizing components from the pyrolysis oil. During the project, the team investigated methods from both classes that were suitable for application in each stage of the pyrolysis process. The post processing stabilization effort performed at PNNL is described in this report. The effort reported here was performed under a CRADA between PNNL and UOP, which was effective on March 13, 2009, for 2 years and was subsequently modified March 8, 2011, to extend the term to December 31, 2011.

  11. Structure, magnetic, and dielectric properties of Ti-doped LaFeO{sub 3} ceramics synthesized by polymer pyrolysis method

    SciTech Connect

    Phokha, Sumalin; Hunpratup, Sitchai; Pinitsoontorn, Supree; Putasaeng, Bundit; Rujirawat, Saroj; Maensiri, Santi

    2015-07-15

    Highlights: • The LaFe{sub 1−x}Ti{sub x}O{sub 3} samples can be successfully prepared by polymer pyrolysis method. • XANES spectra confirmed the mixed valence states of Fe{sup 3+} and Fe{sup 4+} for Fe ions and valence states of Ti{sup 4+} for Ti ions. • The ferromagnetism (FM) at room temperature (RT) can be observed in all LaFe{sub 1−x}Ti{sub x}O{sub 3} nanoparticles and ceramics. • The uncompensated spins at the surface played an important role in the magnetism of LaFe{sub 1−x}Ti{sub x}O{sub 3} nanoparticles. • The giant dielectric behavior of the ceramic samples can be easily found by substitution at B site. - Abstract: Perovskite Ti-doped LaFeO{sub 3} (LaFe{sub 1−x}Ti{sub x}O{sub 3}, x = 0, 0.1, and 0.2) nanoparticles synthesized by the polymer pyrolysis method were investigated. X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray absorption near edge spectroscopy (XANES), and vibrating sample magnetometry (VSM) were used to characterize phase, morphology, valence states and magnetic properties of the samples. The samples had a phase of the orthorhombic structure with crystallite sizes of 25 ± 2–47 ± 2 nm for nanoparticles, while ceramic samples had the grain sizes of 0.9 ± 0.3–6.0 ± 2.3 μm. The result of XANES spectra showed that the Fe{sup 3+}/Fe{sup 4+} and Ti{sup 4+} exist in the samples. The weak ferromagnetic behavior at room temperature is observed for all LaFe{sub 1−x}Ti{sub x}O{sub 3} samples with a maximum magnetization of 0.32 emu/g for x = 0.2. Additionally, larger hysteresis loops induced significantly in ceramic samples with no saturation up to 10 kOe. The dielectric properties as a function of frequency at low temperatures suggest the presence of polarization in the samples due to the electron hopping between Fe{sup 3+} and Fe{sup 4+} ions.

  12. Agricultural Spraying

    NASA Technical Reports Server (NTRS)

    1986-01-01

    AGDISP, a computer code written for Langley by Continuum Dynamics, Inc., aids crop dusting airplanes in targeting pesticides. The code is commercially available and can be run on a personal computer by an inexperienced operator. Called SWA+H, it is used by the Forest Service, FAA, DuPont, etc. DuPont uses the code to "test" equipment on the computer using a laser system to measure particle characteristics of various spray compounds.

  13. Synthesis, characterization and ellipsometric study of ultrasonically sprayed Co3O4 films

    NASA Astrophysics Data System (ADS)

    Gençyılmaz, O.; Taşköprü, T.; Atay, F.; Akyüz, İ.

    2015-10-01

    In the present study, cobalt oxide (Co3O4) films were produced using ultrasonic spray pyrolysis technique onto the glass substrate at different temperatures (200-250-300-350 °C). The effect of substrate temperature on the structural, optical, surface and electrical properties of Co3O4 films was reported. Thickness, refractive index and extinction coefficient of the films were determined by spectroscopic ellipsometry, and X-ray diffraction analyses revealed that Co3O4 films were polycrystalline fcc structure and the substrate temperature significantly improved the crystal structure of Co3O4 films. The films deposited at 350 °C substrate temperature showed the best structural quality. Transmittance, absorbance and reflectance spectra were taken by means of UV-Vis spectrophotometer, and optical band gap values were calculated using optical method. Surface images and roughness values of the films were taken by atomic force microscopy to see the effect of deposition temperature on surface properties. The resistivity of the films slightly decreases with increase in the substrate temperature from 1.08 × 104 to 1.46 × 102 Ω cm. Finally, ultrasonic spray pyrolysis technique allowed production of Co3O4 films, which are alternative metal oxide film for technological applications, at low substrate temperature.

  14. Standardization of Field Methods for Determination of Insecticide Spray Droplet Size

    DTIC Science & Technology

    1977-03-15

    Command Forrestal Building Washington, D. C. 20314 ATTN: MEDDH-SR 2 OFFICE OF NAVAL RESEARCH BIOLOGICAL & MEDICAL ICTENCES DIVISION MICROBIOLOGY PROGRAM...Scientific Background ........................................ 9 3. Objectives ................................................... 12 4. Material & Methods...1970). 12 Silicone treatment of a glass slide leaves an oleophobic layer that prevents irregular spreading of droplets. An impinging droplet spreads

  15. Plasma spraying method for forming diamond and diamond-like coatings

    DOEpatents

    Holcombe, C.E.; Seals, R.D.; Price, R.E.

    1997-06-03

    A method and composition is disclosed for the deposition of a thick layer of diamond or diamond-like material. The method includes high temperature processing wherein a selected composition including at least glassy carbon is heated in a direct current plasma arc device to a selected temperature above the softening point, in an inert atmosphere, and is propelled to quickly quenched on a selected substrate. The softened or molten composition crystallizes on the substrate to form a thick deposition layer comprising at least a diamond or diamond-like material. The selected composition includes at least glassy carbon as a primary constituent and may include at least one secondary constituent. Preferably, the secondary constituents are selected from the group consisting of at least diamond powder, boron carbide (B{sub 4}C) powder and mixtures thereof. 9 figs.

  16. Plasma spraying method for forming diamond and diamond-like coatings

    DOEpatents

    Holcombe, Cressie E.; Seals, Roland D.; Price, R. Eugene

    1997-01-01

    A method and composition for the deposition of a thick layer (10) of diamond or diamond-like material. The method includes high temperature processing wherein a selected composition (12) including at least glassy carbon is heated in a direct current plasma arc device to a selected temperature above the softening point, in an inert atmosphere, and is propelled to quickly quenched on a selected substrate (20). The softened or molten composition (18) crystallizes on the substrate (20) to form a thick deposition layer (10) comprising at least a diamond or diamond-like material. The selected composition (12) includes at least glassy carbon as a primary constituent (14) and may include at least one secondary constituent (16). Preferably, the secondary constituents (16) are selected from the group consisting of at least diamond powder, boron carbide (B.sub.4 C) powder and mixtures thereof.

  17. Synthesis of nickel oxide nanospheres by a facile spray drying method and their application as anode materials for lithium ion batteries

    SciTech Connect

    Xiao, Anguo Zhou, Shibiao; Zuo, Chenggang; Zhuan, Yongbing; Ding, Xiang

    2015-10-15

    Graphical abstract: NiO nanospheres prepared by a facile spray drying method show high lithium ion storage performance as anode of lithium ion battery. - Highlights: • NiO nanospheres are prepared by a spray drying method. • NiO nanospheres are composed of interconnected nanoparticles. • NiO nanospheres show good lithium ion storage properties. - Abstract: Fabrication of advanced anode materials is indispensable for construction of high-performance lithium ion batteries. In this work, nickel oxide (NiO) nanospheres are fabricated by a facial one-step spray drying method. The as-prepared NiO nanospheres show diameters ranging from 100 to 600 nm and are composed of nanoparticles of 30–50 nm. As an anode for lithium ion batteries, the electrochemical properties of the NiO nanospheres are investigated by cyclic voltammetry (CV) and galvanostatic charge/discharge tests. The specific reversible capacity of NiO nanospheres is 656 mA h g{sup −1} at 0.1 C, and 476 mA h g{sup −1} at 1 C. The improvement of electrochemical properties is attributed to nanosphere structure with large surface area and short ion/electron transfer path.

  18. Characterization of the pyrolysis products of methiopropamine.

    PubMed

    Bouso, Emily D; Gardner, Elizabeth A; O'Brien, John E; Talbot, Brian; Kavanagh, Pierce V

    2014-01-01

    1-(Thien-2-yl)-2-methylaminopropane (methiopropamine, MPA), appeared as a 'legal high' in late 2010. It is structurally similar to methamphetamine, with a thiophene ring replacing the benzene moiety. Methiopropamine reportedly retains the pharmacological properties of amphetamine stimulants, but it does not fall under existing drug laws in the USA and Ireland. The objective of this research was to identify the pyrolysis products formed under conditions that mimic those used by recreational drugs users. Thirteen pyrolysis products were identified and ten were confirmed by comparison to synthesized standards. Methods for synthesizing the standards as well as an alternative method for the synthesis of methiopropamine were developed. The MPA pyrolysis products are formed through N-dealkylation, N-alkylation, N-formylation, β-carbon oxidation, β-carbon oxidation/N-alkylation, amine elimination and carbon-carbon bond cleavage. Two pyrazine isomers also formed. Some of these products have the potential to be psychoactive while others are potentially toxic.

  19. Molecular configuration and pyrolysis reactions of phenolic-novolaks.

    NASA Technical Reports Server (NTRS)

    Winkler, E. L.; Parker, J. A.

    1971-01-01

    Description of a statistical method for characterizing the structure of an average phenolic-novolak prepolymer molecule in terms of the total number of phenolic nuclei that compose the molecule and the number of these nuclei that are pendent. It is only necessary to resort to experimental pyrolysis to evaluate the thermokinetic parameters for pyrolysis for the ablator. In addition, the fraction of phenolic involved in the major pyrolysis reactions can be estimated in terms of the parameters previously evaluated. It is shown that the overlapping reactions which occur during pyrolysis of a phenolic-novolak can be resolved by pyrolyzing samples with different extents of cure. It is then possible to determine the kinetic parameters for pyrolysis for the major reactions by well-known methods which often fail when reactions are not well resolved.

  20. Development of an efficient transformation method by Agrobacterium tumefaciens and high throughput spray assay to identify transgenic plants for woodland strawberry (Fragaria vesca) using NPTII selection.

    PubMed

    Pantazis, Christopher J; Fisk, Sarah; Mills, Kerri; Flinn, Barry S; Shulaev, Vladimir; Veilleux, Richard E; Dan, Yinghui

    2013-03-01

    KEY MESSAGE : We developed an efficient Agrobacterium -mediated transformation method using an Ac/Ds transposon tagging construct for F. vesca and high throughput paromomycin spray assay to identify its transformants for strawberry functional genomics. Genomic resources for Rosaceae species are now readily available, including the Fragaria vesca genome, EST sequences, markers, linkage maps, and physical maps. The Rosaceae Genomic Executive Committee has promoted strawberry as a translational genomics model due to its unique biological features and transformability for fruit trait improvement. Our overall research goal is to use functional genomic and metabolic approaches to pursue high throughput gene discovery in the diploid woodland strawberry. F. vesca offers several advantages of a fleshy fruit typical of most fruit crops, short life cycle (seed to seed in 12-16 weeks), small genome size (206 Mbb/C), small plant size, self-compatibility, and many seeds per plant. We have developed an efficient Agrobacterium tumefaciens-mediated strawberry transformation method using kanamycin selection, and high throughput paromomycin spray assay to efficiently identify transgenic strawberry plants. Using our kanamycin transformation method, we were able to produce up to 98 independent kanamycin resistant insertional mutant lines using a T-DNA construct carrying an Ac/Ds transposon Launchpad system from a single transformation experiment involving inoculation of 22 leaf explants of F. vesca accession 551572 within approx. 11 weeks (from inoculation to soil). Transgenic plants with 1-2 copies of a transgene were confirmed by Southern blot analysis. Using our paromomycin spray assay, transgenic F. vesca plants were rapidly identified within 10 days after spraying.

  1. Standardization of chemical analytical techniques for pyrolysis bio-oil: history, challenges, and current status of methods: Bio-oil Analytical Standardization

    SciTech Connect

    Ferrell, Jack R.; Olarte, Mariefel V.; Christensen, Earl D.; Padmaperuma, Asanga B.; Connatser, Raynella M.; Stankovikj, Filip; Meier, Dietrich; Paasikallio, Ville

    2016-07-05

    In this perspective, we discuss the standardization of analytical techniques for pyrolysis bio-oils, including the current status of methods, and our opinions on future directions. First, the history of past standardization efforts is summarized, and both successful and unsuccessful validation of analytical techniques highlighted. The majority of analytical standardization studies to-date has tested only physical characterization techniques. Here, we present results from an international round robin on the validation of chemical characterization techniques for bio-oils. Techniques tested included acid number, carbonyl titrations using two different methods (one at room temperature and one at 80 degrees C), 31P NMR for determination of hydroxyl groups, and a quantitative gas chromatography-mass spectrometry (GC-MS) method. Both carbonyl titration and acid number methods have yielded acceptable inter-laboratory variabilities. 31P NMR produced acceptable results for aliphatic and phenolic hydroxyl groups, but not for carboxylic hydroxyl groups. As shown in previous round robins, GC-MS results were more variable. Reliable chemical characterization of bio-oils will enable upgrading research and allow for detailed comparisons of bio-oils produced at different facilities. Reliable analytics are also needed to enable an emerging bioenergy industry, as processing facilities often have different analytical needs and capabilities than research facilities. We feel that correlations in reliable characterizations of bio-oils will help strike a balance between research and industry, and will ultimately help to determine metrics for bio-oil quality. Finally, the standardization of additional analytical methods is needed, particularly for upgraded bio-oils.

  2. Identification and characterization of vinylpyrrolidone-vinylimidazolium chloride copolymers in cosmetic products by pyrolysis-gas chromatography-mass spectrometry method.

    PubMed

    Gmahl, E; Ruess, W

    1993-04-01

    Synopsis Commercially available copolymers of 1-vinyl-2-pyrrolidone and 1-vinyl-3-methylimidazolium chloride, known as 'Luviquat' types in the cosmetic industry, were analysed for their composition using a combination of pyrolysis-gas chromatography-mass spectrometry method. This is a report on the determined pyrolytic products and the fast identification of the analysed polymers both in raw materials and cosmetic products. Calibration with defined material ensures the determination of monomer ratios with good reproducibility. Résumé Les copolymères de chlorure de 1-vinyle-2-pyrolidone et de 1-vinyle-3-methylimidazolium disponibles dans le commerce, connus dans l'industrie cosmétique sous la dénomination de copolymères de vinyle, ont été analysés à laide d'une méthode combinant la pyrolyse, la spectrométrie de mass et la chromatographie en phase gazeuse. Cet article constitue un rapport sur les produits déterminés par pyrolyse et sur la rapidité d'identification des polymères analysés à la fois dans des matières premières et dans des produits cosmétiques. Le calibrage avec un matériel défini assure une bonne détermination des taux de monomères dotés d'une reproductibilité.

  3. Estimation of a novel method to produce bio-oil from sewage sludge by microwave pyrolysis with the consideration of efficiency and safety.

    PubMed

    Tian, Yu; Zuo, Wei; Ren, Zhengyuan; Chen, Dongdong

    2011-01-01

    This paper presented a feasible method to produce bio-oil from sewage sludge by microwave pyrolysis. The results showed that oils derived under 400 W obtained an attractive yield (49.8 wt.%) with favorable characteristics such as high calorific value (35.0 MJ/kg), low density (929 kg/m3) and preferable chemical composition (29.5 wt.% of monoaromatics). A model to study the relationship between microwave power and mass balance of product fractions was developed, and the results indicated that the power range of the highest transforming efficiency for organics in sludge into oils was 400-600 W, the subsequent increase of power to the range of 600-800 W favored gases formation at the expense of oils, and increase of power to above 800 W led to the conversion of solids into gases, while oils remained unchanged. The analysis of sulfur and nitrogen compounds in oils showed that bio-oil should be extracted before being used as fuel.

  4. Solid dispersion particles of amorphous indomethacin with fine porous silica particles by using spray-drying method.

    PubMed

    Takeuchi, Hirofumi; Nagira, Shinsuke; Yamamoto, Hiromitsu; Kawashima, Yoshiaki

    2005-04-11

    The solid dispersion particles of indomethacin (IMC) were prepared with different types of silica, non-porous (Aerosil 200) or porous silica (Sylysia 350) by using spray-drying method. Powder X-ray diffraction analysis showed that IMC in solid dispersion particles is in amorphous state irrespective of the type of silica formulated. In DSC analysis, the melting peak of IMC in solid dispersion particles with Sylysia 350 shifted to lower temperature than that in solid dispersion particles with Aerosil 200 although the peak of each solid dispersion particles was much smaller than that of original IMC crystals. Dissolution property of IMC was remarkably improved by formulating the silica particles to the solid dispersion particles. In comparing the effect of the type of the silica particles, the dissolution rate of solid dispersion particles with Sylysia 350 was faster than that with Aerosil 200. The formulation amount of IMC did not affect on the amorphous state of IMC in the resultant solid dispersion particles in powder X-ray diffraction patterns. However, the area of the melting peak of IMC in the solid dispersion particles increased and an exothermic peak owing to recrystallization was observed with increasing the IMC content in the DSC patterns. The dissolution rate of IMC from the solid dispersion particles with Sylysia 350 was faster than that of Aerosil 200 irrespective of IMC content. In stability test, amorphous IMC in the solid dispersion particles with each silica particles did not crystallize under storing at severe storage conditions (40 degrees C, 75% RH) for 2 months, while amorphous IMC without silica easily crystallized under same conditions.

  5. Method of forming a leak proof plasma sprayed interconnection layer on an electrode of an electrochemical cell

    DOEpatents

    Kuo, Lewis J. H.; Vora, Shailesh D.

    1995-01-01

    A dense, substantially gas-tight, electrically conductive interconnection layer is formed on an electrode structure of an electrochemical cell by: (A) providing an electrode structure; (B) forming on a selected portion of the electrode surface, an interconnection layer having the general formula La.sub.1-x M.sub.x Cr.sub.1-y N.sub.y O.sub.3, where M is a dopant selected from the group of Ca, Sr, Ba, and mixtures thereof, and where N is a dopant selected from the group of Mg, Co, Ni, Al, and mixtures thereof, and where x and y are each independently about 0.075-0.25, by thermally spraying, preferably plasma arc spraying, a flux added interconnection spray powder, preferably agglomerated, the flux added powder comprising flux particles, preferably including dopant, preferably (CaO).sub.12. (Al.sub.2 O.sub.3).sub.7 flux particles including Ca and Al dopant, and LaCrO.sub.3 interconnection particles, preferably undoped LaCrO.sub.3, to form a dense and substantially gas-tight interconnection material bonded to the electrode structure by a single plasma spraying step; and, (C) heat treating the interconnection layer at from about 1200.degree. to 1350.degree. C. to further densify and heal the micro-cracks and macro-cracks of the thermally sprayed interconnection layer. The result is a substantially gas-tight, highly doped, electrically conductive interconnection material bonded to the electrode structure. The electrode structure can be an air electrode, and a solid electrolyte layer can be applied to the unselected portion of the air electrode, and further a fuel electrode can be applied to the solid electrolyte, to form an electrochemical cell for generation of electrical power.

  6. Method of forming a leak proof plasma sprayed interconnection layer on an electrode of an electrochemical cell

    DOEpatents

    Kuo, L.J.H.; Vora, S.D.

    1995-02-21

    A dense, substantially gas-tight, electrically conductive interconnection layer is formed on an electrode structure of an electrochemical cell by: (A) providing an electrode structure; (B) forming on a selected portion of the electrode surface, an interconnection layer having the general formula La{sub 1{minus}x}M{sub x}Cr{sub 1{minus}y}N{sub y}O{sub 3}, where M is a dopant selected from the group of Ca, Sr, Ba, and mixtures thereof, and where N is a dopant selected from the group of Mg, Co, Ni, Al, and mixtures thereof, and where x and y are each independently about 0.075--0.25, by thermally spraying, preferably plasma arc spraying, a flux added interconnection spray powder, preferably agglomerated, the flux added powder comprising flux particles, preferably including dopant, preferably (CaO){sub 12}(Al{sub 2}O{sub 3}){sub 7} flux particles including Ca and Al dopant, and LaCrO{sub 3} interconnection particles, preferably undoped LaCrO{sub 3}, to form a dense and substantially gas-tight interconnection material bonded to the electrode structure by a single plasma spraying step; and (C) heat treating the interconnection layer at from about 1,200 to 1,350 C to further densify and heal the micro-cracks and macro-cracks of the thermally sprayed interconnection layer. The result is a substantially gas-tight, highly doped, electrically conductive interconnection material bonded to the electrode structure. The electrode structure can be an air electrode, and a solid electrolyte layer can be applied to the unselected portion of the air electrode, and further a fuel electrode can be applied to the solid electrolyte, to form an electrochemical cell for generation of electrical power. 4 figs.

  7. Pyrolysis of the tetra pak

    SciTech Connect

    Korkmaz, Ahmet; Yanik, Jale Brebu, Mihai; Vasile, Cornelia

    2009-11-15

    This study deals with pyrolysis of tetra pak which is widely used as an aseptic beverage packaging material. Pyrolysis experiments were carried out under inert atmosphere in a batch reactor at different temperatures and by different pyrolysis modes (one- and two-step). The yields of char, liquid and gas were quantified. Pyrolysis liquids produced were collected as three separate phases; aqueous phase, tar and polyethylene wax. Characterization of wax and the determination of the total amount of phenols in aqueous phase were performed. Chemical compositions of gas and char products relevant to fuel applications were determined. Pure aluminum can be also recovered by pyrolysis.

  8. ENGINEERING BULLETIN: PYROLYSIS TREATMENT

    EPA Science Inventory

    Pyrolysis is formally defined as chemical decomposition induced in organic materials by heat in the absence of oxygen. In practice, it is not possible to achieve a completely oxygen-free atmosphere; actual pyrolytic systems are operated with less than stoichiometric quantities of...

  9. Pyrolysis of table sugar.

    PubMed

    Bulut, Adnan; Karagöz, Selhan

    2013-01-01

    Table sugars were pyrolyzed at different temperatures (300, 400, and 500°C) in a fixed-bed reactor. The effect of pyrolysis temperature on yields of liquid, solid, and gaseous products was investigated. As expected the yield of liquid products gradually increased and the yield of solid products gradually decreased when the pyrolysis temperature was raised. The yield of liquid products was greatest (52 wt%) at 500°C. The composition of bio-oils extracted with diethyl ether was identified by means of gas chromatography mass spectrometry (GC-MS), nuclear magnetic resonance ((1)H-NMR), and Fourier transform infrared spectroscopy (FTIR). The following compounds were observed in bio-oils produced from the pyrolysis of table sugar at 500°C: 1,4:3,6-dianhydro- α -d-glucopyranose, 5-(hydroxymethyl) furfural, 5-acetoxymethyl-2-furaldehyde, and cyclotetradecane liquid product. The relative concentration of 5-(hydroxymethyl) furfural was the highest in bio-oils obtained from pyrolysis of table sugars at 500°C.

  10. Vaccination of commercial broiler chicks against avian metapneumovirus infection: a comparison of drinking-water, spray and oculo-oral delivery methods.

    PubMed

    Ganapathy, Kannan; Bufton, Andrew; Pearson, Andrew; Lemiere, Stephane; Jones, Richard C

    2010-05-21

    Avian metapneumovirus (aMPV) has become an important cause of viral respiratory infections in turkey and chickens. Live and inactivated vaccinations are available worldwide for prevention of disease and economic losses caused by this pathogen. The efficacy of these vaccines is vigorously tested under laboratory conditions prior to use in the field. In this study, a live subtype B aMPV vaccine was administered by spray, drinking water or oculo-oral methods to separate groups of broiler chicks under field conditions. Following this, the chicks were immediately transferred to separate rooms in an experimental isolation house, monitored and challenged with virulent subtype B aMPV. No clinical signs were recorded following the vaccination methods. In the oculo-oral vaccinated chicks, 40-60% of the birds were vaccine virus positive by RT-PCR. In addition, in comparison to other groups, statistically higher levels of aMPV ELISA antibodies were detected. After spray vaccination, the number of chicks positive for the vaccine virus increased gradually from 10% at one week to 30% by 3 weeks post vaccination. Following drinking water vaccination, 30% of chicks were aMPV positive at 1 week but negative by 3 weeks post vaccination. In both, spray and drinking water vaccinated groups, no ELISA antibodies were detected, but when challenged all chicks were protected against disease. At 5 days post challenge, 100% of chicks in the unvaccinated and those vaccinated by spray or drinking water routes but only 20% of the oculo-oral-vaccinated chicks were aMPV positive by RT-PCR. At 10 days post challenge, 10% of chicks in each group were aMPV RT-PCR positive. On challenge, all vaccinated chicks were protected against disease. It appears that when aMPV vaccine is accurately applied to chicks by spray or drinking water routes, both are capable of giving protection against clinical disease equal to that induced in those chicks vaccinated individually by the oculo-oral route.

  11. A new derivatization method for δ18O analysis of individual carbohydrates with GC-Pyrolysis-IRMS

    NASA Astrophysics Data System (ADS)

    Lehmann, M. M.; Siegwolf, R. T.; Saurer, M.; Blees, J.; Fischer, M.; Zech, M.

    2015-12-01

    Compound specific isotope analysis (CSIA) with gas chromatography coupled to an isotope ratio mass spectrometer (GC-Pyr-IRMS) is nowadays a powerful tool that is widely used by a broad spectrum of research fields to investigate the isotopic signature of diverse metabolites. While many CSIA methods for carbon, hydrogen, and nitrogen isotopes are known, CSIA methods for the analysis of oxygen isotopes (δ18O) are still not widely established. Especially, reliable and precise methods for the δ18O analyses of individual carbohydrates are scarce, which is caused by the highly sensitive nature of the sugars. However, carbohydrates are important components of living organisms, source for many biochemical reactions, and can be found in all organisms, in soils, sediments, and in air. Thus, a method, allowing the investigation of the 18O/16O ratio in carbohydrates will enhance the scope of research using isotopes. We developed a new and easy to handle derivatization method to determine δ18O in carbohydrates with GC-Pyr-IRMS that consists of a catalyzed one-pot reaction in acetonitrile, resulting in complete methylation of all sugar hydroxyl groups within 24 hours, with silver oxide as the proton acceptor and methyl iodide as the methyl group carrier. Results derived from standard material show unrivalled δ18O precision ranging from about 0.2 to 1.1 ‰ for different individual carbohydrates of different classes and a generally very good accuracy, with a narrow range of 0.2 ‰ around the reference value, despite of high area variations. We applied this method on real samples, demonstrating that the method can commonly be used for analyzing honey samples, and for the analyses of more complex carbohydrate mixtures from plant leaves, including glucose, fructose, pinitol, and sucrose. Our new method may be used for food, beverage, and medical applications, as well as for biogeochemical and paleoclimatic sciences.

  12. Using different chemical methods for deposition of copper selenide thin films and comparison of their characterization.

    PubMed

    Güzeldir, Betül; Sağlam, Mustafa

    2015-11-05

    Different chemical methods such as Successive Ionic Layer Adsorption and Reaction (SILAR), spin coating and spray pyrolysis methods were used to deposite of copper selenide thin films on the glass substrates. The films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), energy dispersive X-ray analysis (EDX) spectroscopy and UV-vis spectrophotometry. The XRD and SEM studies showed that all the films exhibit polycrystalline nature and crystallinity of copper selenide thin films prepared with spray pyrolysis greater than spin coating and SILAR methods. From SEM and AFM images, it was observed copper selenide films were uniform on the glass substrates without any visible cracks or pores. The EDX spectra showed that the expected elements exist in the thin films. Optical absorption studies showed that the band gaps of copper selenide thin films were in the range 2.84-2.93 eV depending on different chemical methods. The refractive index (n), optical static and high frequency dielectric constants (ε0, ε∞) values were calculated by using the energy bandgap values for each deposition method. The obtained results from different chemical methods revealed that the spray pyrolysis technique is the best chemical deposition method to fabricate copper selenide thin films. This absolute advantage was lead to play key roles on performance and efficiency electrochromic and photovoltaic devices.

  13. Additives initiate selective production of chemicals from biomass pyrolysis.

    PubMed

    Leng, Shuai; Wang, Xinde; Wang, Lei; Qiu, Huizhe; Zhuang, Guilin; Zhong, Xing; Wang, Jianguo; Ma, Fengyun; Liu, Jingmei; Wang, Qiang

    2014-03-01

    To improve chemicals selectivity under low temperature, a new method that involves the injection of additives into biomass pyrolysis is introduced. This method allows biomass pyrolysis to achieve high selectivity to chemicals under low temperature (300°C), while nothing was obtained in typical pyrolysis under 300°C. However, by using the new method, the first liquid drop emerged at the interval between 140°C and 240°C. Adding methanol to mushroom scrap pyrolysis obtained high selectivity to acetic acid (98.33%), while adding ethyl acetate gained selectivity to methanol (65.77%) in bagasse pyrolysis and to acetone (72.51%) in corncob pyrolysis. Apart from basic chemicals, one high value-added chemical (2,3-dihydrobenzofuran) was also detected, which obtained the highest selectivity (10.33%) in corncob pyrolysis through the addition of ethyl acetate. Comparison of HZSM-5 and CaCO3 catalysis showed that benzene emerged in the liquid because of the larger degree of cracking and hydrodeoxygenation over HZSM-5.

  14. Rapid method for hydrocarbon-type analysis of heavy oils and synthetic fuels by pyrolysis thin layer chromatography

    SciTech Connect

    Poirier, M.A.; George, A.E.

    1982-09-01

    This work describes a rapid method for hydrocargon-type analysis applying thin layer chromatography (TLC) to the pentane-soluble fraction *malthenes) of the petroleum and synthetic fuels boiling above 200/sup 0/C. The principal component types encountered in this paper are saturates (SA), aromatics (AR), (mono and di together) polynuclear aromatics (PNA) and polar material (PO). The method uses a Iatroscan TLC pyrolyzer which combines the resolution capabilities of TLC with the possibility of quantification by using a flame-ionization detector (FID). Comparison of the results with those obtained by the API-60 procedure is presented.

  15. Investigation of waste biomass co-pyrolysis with petroleum sludge using a response surface methodology.

    PubMed

    Hu, Guangji; Li, Jianbing; Zhang, Xinying; Li, Yubao

    2017-05-01

    The treatment of waste biomass (sawdust) through co-pyrolysis with refinery oily sludge was carried out in a fixed-bed reactor. Response surface method was applied to evaluate the main and interaction effects of three experimental factors (sawdust percentage in feedstock, temperature, and heating rate) on pyrolysis oil and char yields. It was found that the oil and char yields increased with sawdust percentage in feedstock. The interaction between heating rate and sawdust percentage as well as between heating rate and temperature was significant on the pyrolysis oil yield. The higher heating value of oil originated from sawdust during co-pyrolysis at a sawdust/oily sludge ratio of 3:1 increased by 5 MJ/kg as compared to that during sawdust pyrolysis alone, indicating a synergistic effect of co-pyrolysis. As a result, petroleum sludge can be used as an effective additive in the pyrolysis of waste biomass for improving its energy recovery.

  16. Planar Droplet Sizing in Dense Sprays

    DTIC Science & Technology

    2013-04-01

    Transactions of the ASME 121(3): 409-414. Sick, V. and B. Stojkovic (2001). "Attenuation effects on imaging diagnostics of hollow - cone sprays ...considered in the data processing method. Imaging of the scattered light from the spray was performed by a 12bit CCD camera ( Model PCO sensical QE...the spray was performed using a laser power meter. The motorised linear stage was acquired from Thorlabs MTS50 models (Figure 5). The positioning

  17. Successful field trial of attractive toxic sugar bait (ATSB) plant-spraying methods against malaria vectors in the Anopheles gambiae complex in Mali, West Africa

    PubMed Central

    2010-01-01

    Background Based on highly successful demonstrations in Israel that attractive toxic sugar bait (ATSB) methods can decimate local populations of mosquitoes, this study determined the effectiveness of ATSB methods for malaria vector control in the semi-arid Bandiagara District of Mali, West Africa. Methods Control and treatment sites, selected along a road that connects villages, contained man-made ponds that were the primary larval habitats of Anopheles gambiae and Anopheles arabiensis. Guava and honey melons, two local fruits shown to be attractive to An. gambiae s.l., were used to prepare solutions of Attractive Sugar Bait (ASB) and ATSB that additionally contained boric acid as an oral insecticide. Both included a color dye marker to facilitate determination of mosquitoes feeding on the solutions. The trial was conducted over a 38-day period, using CDC light traps to monitor mosquito populations. On day 8, ASB solution in the control site and ATSB solution in the treatment site were sprayed using a hand-pump on patches of vegetation. Samples of female mosquitoes were age-graded to determine the impact of ATSB treatment on vector longevity. Results Immediately after spraying ATSB in the treatment site, the relative abundance of female and male An. gambiae s.l. declined about 90% from pre-treatment levels and remained low. In the treatment site, most females remaining after ATSB treatment had not completed a single gonotrophic cycle, and only 6% had completed three or more gonotrophic cycles compared with 37% pre-treatment. In the control site sprayed with ASB (without toxin), the proportion of females completing three or more gonotrophic cycles increased from 28.5% pre-treatment to 47.5% post-treatment. In the control site, detection of dye marker in over half of the females and males provided direct evidence that the mosquitoes were feeding on the sprayed solutions. Conclusion This study in Mali shows that even a single application of ATSB can substantially

  18. Detection of segmentation cracks in top coat of thermal barrier coatings during plasma spraying by non-contact acoustic emission method.

    PubMed

    Ito, Kaita; Kuriki, Hitoshi; Araki, Hiroshi; Kuroda, Seiji; Enoki, Manabu

    2014-06-01

    Numerous cracks can be observed in the top coat of thermal barrier coatings (TBCs) deposited by the atmospheric plasma spraying (APS) method. These cracks can be classified into vertical and horizontal ones and they have opposite impact on the properties of TBCs. Vertical cracks reduce the residual stress in the top coat and provide strain tolerance. On the contrary, horizontal cracks trigger delamination of the top coat. However, monitoring methods of cracks generation during APS are rare even though they are strongly desired. Therefore, an in situ, non-contact and non-destructive evaluation method for this objective was developed in this study with the laser acoustic emission (AE) technique by using laser interferometers as a sensor. More AE events could be detected by introducing an improved noise reduction filter and AE event detection procedures with multiple thresholds. Generation of vertical cracks was successfully separated from horizontal cracks by a newly introduced scanning pattern of a plasma torch. Thus, generation of vertical cracks was detected with certainty by this monitoring method because AE events were detected only during spraying and a positive correlation was observed between the development degree of vertical cracks and the total AE energy in one experiment.

  19. Detection of segmentation cracks in top coat of thermal barrier coatings during plasma spraying by non-contact acoustic emission method

    PubMed Central

    Ito, Kaita; Kuriki, Hitoshi; Araki, Hiroshi; Kuroda, Seiji; Enoki, Manabu

    2014-01-01

    Numerous cracks can be observed in the top coat of thermal barrier coatings (TBCs) deposited by the atmospheric plasma spraying (APS) method. These cracks can be classified into vertical and horizontal ones and they have opposite impact on the properties of TBCs. Vertical cracks reduce the residual stress in the top coat and provide strain tolerance. On the contrary, horizontal cracks trigger delamination of the top coat. However, monitoring methods of cracks generation during APS are rare even though they are strongly desired. Therefore, an in situ, non-contact and non-destructive evaluation method for this objective was developed in this study with the laser acoustic emission (AE) technique by using laser interferometers as a sensor. More AE events could be detected by introducing an improved noise reduction filter and AE event detection procedures with multiple thresholds. Generation of vertical cracks was successfully separated from horizontal cracks by a newly introduced scanning pattern of a plasma torch. Thus, generation of vertical cracks was detected with certainty by this monitoring method because AE events were detected only during spraying and a positive correlation was observed between the development degree of vertical cracks and the total AE energy in one experiment. PMID:27877683

  20. Development and beyond: Strategy for long-term maintenance of an online laser diffraction particle size method in a spray drying manufacturing process.

    PubMed

    Medendorp, Joseph; Bric, John; Connelly, Greg; Tolton, Kelly; Warman, Martin

    2015-08-10

    The purpose of this manuscript is to present the intended use and long-term maintenance strategy of an online laser diffraction particle size method used for process control in a spray drying process. A Malvern Insitec was used for online particle size measurements and a Malvern Mastersizer was used for offline particle size measurements. The two methods were developed in parallel with the Mastersizer serving as the reference method. Despite extensive method development across a range of particle sizes, the two instruments demonstrated different sensitivities to material and process changes over the product lifecycle. This paper will describe the procedure used to ensure consistent alignment of the two methods, thus allowing for continued use of online real-time laser diffraction as a surrogate for the offline system over the product lifecycle.

  1. Pyrolysis process and apparatus

    DOEpatents

    Lee, Chang-Kuei

    1983-01-01

    This invention discloses a process and apparatus for pyrolyzing particulate coal by heating with a particulate solid heating media in a transport reactor. The invention tends to dampen fluctuations in the flow of heating media upstream of the pyrolysis zone, and by so doing forms a substantially continuous and substantially uniform annular column of heating media flowing downwardly along the inside diameter of the reactor. The invention is particularly useful for bituminous or agglomerative type coals.

  2. Fabrication of superhydrophobic coating via spraying method and its applications in anti-icing and anti-corrosion

    NASA Astrophysics Data System (ADS)

    Pan, Sai; Wang, Nan; Xiong, Dangsheng; Deng, Yaling; Shi, Yan

    2016-12-01

    Superhydrophobic coating was fabricated by spraying the mixture of poly (methyl methacrylate) (PMMA) and hydrophobic silica nanoparticles (SNs) on steel surface. Anti-icing tests were carried out in two ways: freezing water (0 °C) dripping and condensation of atmospheric humidity in low temperature (-20 °C). In the water dripping test, no ice film could be observed compared with steel substrate, due to the bouncing behavior of water droplet; while in the condensing condition, the superior anti-icing behavior could be attributed to the overcooled water that formed on superhydrophobic coating. Besides, the prepared surface exhibited outstanding anti-corrosion character.

  3. Magnetic metal-organic frameworks: γ-Fe2O3@MOFs via confined in situ pyrolysis method for drug delivery.

    PubMed

    Wu, Yi-nan; Zhou, Meimei; Li, Shu; Li, Zehua; Li, Jie; Wu, Baozhen; Li, Guangtao; Li, Fengting; Guan, Xiaohong

    2014-07-23

    A general one-step in situ pyrolysis route for the construction of metal-organic frameworks encapsulating superparamagnetic γ-Fe2O3NPs dispersed in the confined cavities of MOFs homogeneously is described. The integration of γ-Fe2O3 NPs or clusters into MOFs can endow these porous materials with superparamagnetic element. By the combination of the thermal stability of MOFs and pyrolysis of metal triacetylacetonate complex at matched conditions, the porous structure of MOFs are well maintained while the size-induced superparamagnetic property of nano γ-Fe2O3 is obtained. As a proof of concept, both the γ- Fe2O3@ZIF-8 and γ-Fe2O3@MIL-53(Al) were successfully prepared, and the latter was chosen to demonstrate its potential drug delivery as a magnetic MOF.

  4. On methane pyrolysis special applications

    NASA Astrophysics Data System (ADS)

    Toncu, D. C.; Toncu, G.; Soleimani, S.

    2015-11-01

    Methane pyrolysis represents one of the most important processes in industrial use, with applications rising from the chemical and petrochemical industry, combustion, materials and protective coatings. Despite the intense research, experimental data lack kinetic aspects, and the thermodynamics involved often leads to inaccurate results when applied to various systems. Carrying out a comparative analysis of several available data on methane pyrolysis, the paper aims to study the phenomenon of methane pyrolysis under different environments (combustion and plasma), concluding on the most possible reaction pathways involved in many of its applications. Computer simulation using different database underlines the conclusion, helping to the understanding of methane pyrolysis importance in future technologies.

  5. Catalytic pyrolysis of automobile shredder residue

    SciTech Connect

    Arzoumanidis, G.G.; McIntosh, M.J.; Steffensen, E.J.

    1995-07-01

    In the United States, approximately 10 million automobiles are scrapped and shredded each year. The mixture of plastics and other materials remaining after recovery of the metals is known as Automobile Shredder Residue (ASR). In 1994, about 3.5 million tons of ASR was produced and disposed of in landfills. However, environmental, legislative, and economic considerations are forcing the industry to search for recycling or other alternatives to disposal. Numerous studies have been done relating the ASR disposal problem to possible recycling treatments such as pyrolysis, gasification, co-liquefaction of ASR with coal, chemical recovery of plastics from ASR, catalytic pyrolysis, reclamation in molten salts, and vacuum pyrolysis. These and other possibilities have been studied intensively, and entire symposia have been devoted to the problem. Product mix, yields, toxicology issues, and projected economics of conceptual plant designs based on experimental results are among the key elements of past studies. Because the kinds of recycling methods that may be developed, along with their ultimate economic value, depend on a very large number of variables, these studies have been open-ended. It is hoped that it may be useful to explore some of these previously studied areas from fresh perspectives. One such approach, currently under development at Argonne National Laboratory, is the catalytic pyrolysis of ASR.

  6. Pyrolysis of Rubber in a Screw Reactor

    NASA Astrophysics Data System (ADS)

    Lozhechnik, A. V.; Savchin, V. V.

    2016-11-01

    On the basis of an analysis of thermal methods described in the literature and from the results of experimental investigations of steam conversion, the authors have developed and created a facility for thermal processing of rubber waste. Rubber crumb was used as the raw material; the temperature in the reactor was 500°C; nitrogen, steam, and a mixture of light hydrocarbons (noncondensable part of pyrolysis products) represented the working medium. The pyrolysis yielded 36-38% of a solid fraction, 54-56% of a liquid hydrocarbon fraction, and 6-9% of noncondensable gases. Changes in the composition of the gas mixture have been determined at different stages of processing. Gas chromatography of pyrolysis gases has shown that the basic gases produced by pyrolysis are H2 and hydrocarbons C2H4, C3H6, C3H8, C4H8, C2H6, C3H6O2, and C4H10, and a small amount of H2S, CO, and CO2. Noncondensable gases will be used as a fuel to heat the reactor and to implement the process.

  7. [Study on Microwave Co-Pyrolysis of Low Rank Coal and Circulating Coal Gas].

    PubMed

    Zhou, Jun; Yang, Zhe; Liu, Xiao-feng; Wu, Lei; Tian, Yu-hong; Zhao, Xi-cheng

    2016-02-01

    The pyrolysis of low rank coal to produce bluecoke, coal tar and gas is considered to be the optimal method to realize its clean and efficient utilization. However, the current mainstream pyrolysis production technology generally has a certain particle size requirements for raw coal, resulting in lower yield and poorer quality of coal tar, lower content of effective components in coal gas such as H₂, CH₄, CO, etc. To further improve the yield of coal tar obtained from the pyrolysis of low rank coal and explore systematically the effect of microwave power, pyrolysis time and particle size of coal samples on the yield and composition of microwave pyrolysis products of low rank coal through the analysis and characterization of products with FTIR and GC-MS, introducing microwave pyrolysis of low rank coal into the microwave pyrolysis reactor circularly was suggested to carry out the co-pyrolysis experiment of the low rank coal and coal gas generated by the pyrolysis of low rank coal. The results indicated that the yield of the bluecoke and liquid products were up to 62.2% and 26.8% respectively when the optimal pyrolysis process conditions with the microwave power of 800W, pyrolysis time of 40 min, coal samples particle size of 5-10 mm and circulating coal gas flow rate of 0.4 L · min⁻¹ were selected. The infrared spectrogram of the bluecoke under different microwave power and pyrolysis time overlapped roughly. The content of functional groups with -OH, C==O, C==C and C−O from the bluecoke through the pyrolysis of particle size coal samples had a larger difference. To improve microwave power, prolonging pyrolysis time and reducing particle size of coal samples were conducive to converting heavy component to light one into coal tar.

  8. Comparative study on pyrolysis of lignocellulosic and algal biomass using a thermogravimetric and a fixed-bed reactor.

    PubMed

    Yuan, Ting; Tahmasebi, Arash; Yu, Jianglong

    2015-01-01

    Pyrolysis characteristics of four algal and lignocellulosic biomass samples were studied by using a thermogravimetric analyzer (TGA) and a fixed-bed reactor. The effects of pyrolysis temperature and biomass type on the yield and composition of pyrolysis products were investigated. The average activation energy for pyrolysis of biomass samples by FWO and KAS methods in this study were in the range of 211.09-291.19kJ/mol. CO2 was the main gas component in the early stage of pyrolysis, whereas H2 and CH4 concentrations increased with increasing pyrolysis temperature. Bio-oil from Chlorellavulgaris showed higher content of nitrogen containing compounds compared to lignocellulosic biomass. The concentration of aromatic organic compounds such as phenol and its derivatives were increased with increasing pyrolysis temperature up to 700°C. FTIR analysis results showed that with increasing pyrolysis temperature, the concentration of OH, CH, CO, OCH3, and CO functional groups in char decreased sharply.

  9. High-performance graphene/sulphur electrodes for flexible Li-ion batteries using the low-temperature spraying method.

    PubMed

    Kumar, Pushpendra; Wu, Feng-Yu; Hu, Lung-Hao; Ali Abbas, Syed; Ming, Jun; Lin, Chia-Nan; Fang, Jason; Chu, Chih-Wei; Li, Lain-Jong

    2015-05-07

    Elementary sulphur (S) has been shown to be an excellent cathode material in energy storage devices such as Li-S batteries owing to its very high capacity. The major challenges associated with the sulphur cathodes are structural degradation, poor cycling performance and instability of the solid-electrolyte interphase caused by the dissolution of polysulfides during cycling. Tremendous efforts made by others have demonstrated that encapsulation of S materials improves their cycling performance. To make this approach practical for large scale applications, the use of low-cost technology and materials has become a crucial and new focus of S-based Li-ion batteries. Herein, we propose to use a low temperature spraying process to fabricate graphene/S electrode material, where the ink is composed of graphene flakes and the micron-sized S particles prepared by grinding of low-cost S powders. The S particles are found to be well hosted by highly conductive graphene flakes and consequently superior cyclability (∼70% capacity retention after 250 cycles), good coulombic efficiency (∼98%) and high capacity (∼1500 mA h g(-1)) are obtained. The proposed approach does not require high temperature annealing or baking; hence, another great advantage is to make flexible Li-ion batteries. We have also demonstrated two types of flexible batteries using sprayed graphene/S electrodes.

  10. Research on air sprays and unique foam application methods. Phase II report. Laboratory investigation of foam systems

    SciTech Connect

    Not Available

    1982-06-01

    The objective of this study is to assess the effectiveness of air sprays and foam systems for dust control on longwall double-drum shearer faces. Laboratory testing has been conducted using foam systems and promising results have been obtained. Upon Bureau approval, underground testing will be scheduled to assess the effectiveness of foam systems under actual operating conditions. Laboratory testing of air sprays is being conducted at present. This report presents the results of the laboratory testing of foam systems. Specifically, the results obtained on the evaluation of selected foaming agents are presented, the feasibility investigation of flushing foam through the shearer-drum are demonstrated, and conceptual layout of the foam system on the shearer is discussed. The laboratory investigation of the selected foaming agents reveal that the Onyx Microfoam, Onyx Maprosyl and DeTer Microfoam foaming agents have higher expansion ratios compared to the others tested. Flushing foam through the shearer drum is entirely feasible and could be a viable technique for dust suppression on longwall faces.

  11. Surface characteristic of chemically converted graphene coated low carbon steel by electro spray coating method for polymer electrolyte membrane fuel cell bipolar plate.

    PubMed

    Kim, Jungsoo; Kim, Yang Do; Nam, Dae Geun

    2013-05-01

    Graphene was coated on low carbon steel (SS400) by electro spray coating method to improve its properties of corrosion resistance and contact resistance. Exfoliated graphite was made of the graphite by chemical treatment (Chemically Converted Graphene, CCG). CCG is distributed using dispersing agent, and low carbon steel was coated with diffuse graphene solution by electro spray coating method. The structure of the CCG was analyzed using XRD and the coating layer of surface was analyzed using SEM. Analysis showed that multi-layered graphite structure was destroyed and it was transformed in to fine layers graphene structure. And the result of SEM analysis on the surface and the cross section, graphene layer was uniformly formed with 3-5 microm thickness on the surface of substrate. Corrosion resistance test was applied in the corrosive solution which is similar to the polymer electrolyte membrane fuel cell (PEMFC) stack inside. And interfacial contact resistance (ICR) test was measured to simulate the internal operating conditions of PEMFC stack. As a result of measuring corrosion resistance and contact resistance, it could be confirmed that low carbon steel coated with CCG was revealed to be more effective in terms of its applicability as PEMFC bipolar plate.

  12. Thin layer chromatography-spray mass spectrometry: a method for easy identification of synthesis products and UV filters from TLC aluminum foils.

    PubMed

    Himmelsbach, Markus; Waser, Mario; Klampfl, Christian W

    2014-06-01

    A straightforward procedure for direct mass spectrometric (MS) analysis of spots from thin layer chromatography (TLC) plates, without the need of an external ion source, was developed using the aluminum plate backing as spray tip. The spots were cut out shaped as a tip with a 60° angle, mounted in front of the MS orifice, and after addition of a spray solvent spectra were obtained immediately. A high-resolution time-of-flight MS was used since the method is of particular interest for rapid identification or confirmation of spots from TLC plates. The practical benefits of this technique were demonstrated by detection of by-products of organic reactions, by identification of degradation products, and by accurate confirmation of spots when UV filters in sunscreens were analyzed by TLC. Employing the described method TLC spots can be evaluated fast without the need of an external ion source or devices for analyte transfer from TLC to MS, only a basic MS instrument and a high-voltage power supply is required.

  13. Theoretical study of the pyrolysis of vanillin as a model of secondary lignin pyrolysis

    NASA Astrophysics Data System (ADS)

    Wang, Meng; Liu, Chao; Xu, Xiaoxiao; Li, Qibin

    2016-06-01

    The unimolecular and bimolecular decomposition reactions in processes of vanillin pyrolysis were theoretically investigated by employing density functional theory (DFT) method at M06-2X/6-31 G+(d,p) level. The result shows that the homolytic cleavage of O-CH3 bond could be the dominant initial step in the pyrolysis of vanillin. The hydrogen abstractions from functional groups of vanillin by the formed radicals play important roles in the formation of main products. Both formyl, hydroxyl and methoxyl group contribute to the formation of CO. Benzene is formed from the hydrogen addition reaction between hydrogen radical and phenol at high temperature.

  14. Dynamic characteristics of pulsed supersonic fuel sprays

    NASA Astrophysics Data System (ADS)

    Pianthong, K.; Matthujak, A.; Takayama, K.; Milton, B. E.; Behnia, M.

    2008-06-01

    This paper describes the dynamic characteristics of pulsed, supersonic liquid fuel sprays or jets injected into ambient air. Simple, single hole nozzles were employed with the nozzle sac geometries being varied. Different fuel types, diesel fuel, bio-diesel, kerosene, and gasoline were used to determine the effects of fuel properties on the spray characteristics. A vertical two-stage light gas gun was employed as a projectile launcher to provide a high velocity impact to produce the liquid jet. The injection pressure was around 0.88-1.24 GPa in all cases. The pulsed, supersonic fuel sprays were visualized by using a high-speed video camera and shadowgraph method. The spray tip penetration and velocity attenuation and other characteristics were examined and are described here. An instantaneous spray tip velocity of 1,542 m/s (Mach number 4.52) was obtained. However, this spray tip velocity can be sustained for only a very short period (a few microseconds). It then attenuates very quickly. The phenomenon of multiple high frequency spray pulses generated by a single shot impact and the changed in the angle of the shock structure during the spray flight, which had already been observed in previous studies, is again noted. Multiple shock waves from the conical nozzle spray were also clearly captured.

  15. Very Large Eddy Simulations of a Jet-A Spray Reacting Flow in a Single Element LDI Injector With and Without Invoking an Eulerian Scalar DWFDF Method

    NASA Technical Reports Server (NTRS)

    Shih, Tsan-Hsing; Liu, Nan-Suey

    2013-01-01

    This paper presents the very large eddy simulations (VLES) of a Jet-A spray reacting flow in a single element lean direct injection (LDI) injector by using the National Combustion Code (NCC) with and without invoking the Eulerian scalar DWFDF method, in which DWFDF is defined as the density weighted time filtered fine grained probability density function. The flow field is calculated by using the time filtered compressible Navier-Stokes equations (TFNS) with nonlinear subscale turbulence models, and when the Eulerian scalar DWFDF method is invoked, the energy and species mass fractions are calculated by solving the equation of DWFDF. A nonlinear subscale model for closing the convection term of the Eulerian scalar DWFDF equation is used and will be briefly described in this paper. Detailed comparisons between the results and available experimental data are carried out. Some positive findings of invoking the Eulerian scalar DWFDF method in both improving the simulation quality and maintaining economic computing cost are observed.

  16. Hair spray poisoning

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/002705.htm Hair spray poisoning To use the sharing features on this page, please enable JavaScript. Hair spray poisoning occurs when someone breathes in (inhales) ...

  17. Triamcinolone Nasal Spray

    MedlinePlus

    ... itchy nose and itchy, watery eyes caused by hay fever or other allergies. Triamcinolone nasal spray should not ... germs.Triamcinolone nasal spray controls the symptoms of hay fever and allergies but does not cure these conditions. ...

  18. Mometasone Nasal Spray

    MedlinePlus

    ... sneezing, runny, stuffy, or itchy nose caused by hay fever or other allergies. It is also used to ... using mometasone nasal spray to prevent or relieve hay fever or allergy symptoms, it is usually sprayed in ...

  19. Flunisolide Nasal Spray

    MedlinePlus

    ... sneezing, runny, stuffy, or itchy nose caused by hay fever or other allergies. Flunisolide nasal spray should not ... germs.Flunisolide nasal spray controls the symptoms of hay fever or allergies but does not cure these conditions. ...

  20. Nasal corticosteroid sprays

    MedlinePlus

    ... or concerns about your symptoms Trouble using the medicine Alternative Names Steroid nasal sprays; Allergies - nasal corticosteroid sprays References American Academy of ... of Medicine, Division of Allergy, Immunology, and Rheumatology, Georgetown University ...

  1. Structural, Optical, and Electrical Characterization of Spray Pyrolysed Indium Sulfide Thin Films

    NASA Astrophysics Data System (ADS)

    Rahman, F.; Podder, J.; Ichimura, M.

    2013-03-01

    Indium sulfide (In2S3) thin films were deposited onto the glass substrates by a low cost simple spray pyrolysis technique at 300°C temperature. Aqueous solution of indium chloride and thiourea were used to deposit the binary In-S film. The deposited thin films were annealed at 400° and 500°C temperatures and characterized structurally, optically and electrically using EDX, X-ray diffraction, UV-visible spectroscopy and four probe van der Pauw methods. The optical constants such as refractive index and extinction coefficient are calculated from absorbance and transmittance data from 300 to 1100 nm wavelength. The optical transmittance increased after annealing at 400° and 500°C. The band gap energy was reduced from 2.90 to 2.50 eV after annealing the as deposited films. The electrical conductivity as well as the activation energy was increased after annealing the samples.

  2. Growth, microstructure, optical and electrical properties of sprayed CuInSe{sub 2} polycrystalline films

    SciTech Connect

    Akl, Alaa A.; Afify, H.H.

    2008-06-03

    Polycrystalline thin films of CuInSe{sub 2} have been prepared by chemical spray pyrolysis technique as a function of Cu/In ratio. Incremental growth of the various ratios followed at different substrate temperatures ranging from 548 to 623 K. Characterizations by means of compositional analysis, X-ray diffraction and spectrophotometry measurements have been carried out. Voigt profile method has been used to determine the microstructure parameter (crystallite/domain size and macrostrain). The effect of Cu/In ratio as well as substrate temperature on the optical features (absorption coefficient and band gap) of these films has been investigated. The films of different Cu/In ratios (0.9-1.1) displayed a band gap from 0.92 to 1.025 eV for direct transition. The dark resistivity measurements at room temperature of Cu-rich samples show about five orders of magnitude higher than that of In-rich samples.

  3. Optical properties of double layer thin films zinc oxide doping aluminum (ZnO/Al) were deposited on glass substrates by sol gel method spray coating technique

    NASA Astrophysics Data System (ADS)

    Permatasari, Anes; Sutanto, Heri; Marito Siagian, Sinta

    2017-01-01

    Thin films of double layer of ZnO/Al has succeeded in deposition on a glass substrate using sol-gel method and spray coating techniques. Variations of doping Al as much as 2%, 4%, 6% and 8%. ZnO precursor synthesized using zinc acetate dehydrate (Zn(COOCH3)2.2H2O), isopropanol ((CH3)2CHOH) and monoethanolamine (MEA) were stirred using a magnetic stirrer for 45 minutes. ZnO precursor get homogeneous and then added of aluminum nitrate nonahydrate predetermined doping concentration and stirred again for 15 minutes. Deposition solution is done by the spray on a glass substrate and then heated at a temperature of 450°C. A layer of ZnO/Al deposited over the ZnO to produce a thin layer of a double layer. Optical properties layer of ZnO/Al characterized using UV-Vis spectrophotometer. Based on data from UV-Vis absorbance was determined the value of the energy band gap. Pure and dopped layers has different energy due the Al dopping. For pure ZnO layer has energy band gap of 3.347 eV and decreased to 3.09 eV for ZnO layer with Al dopant.

  4. Delamination Strength of WC-Co Thermal-Sprayed Coating Under Combined Stresses by Torsion-Tension Pin-Test Method

    NASA Astrophysics Data System (ADS)

    Kaneko, Kenji; Higaki, Keitaro

    2014-08-01

    In this report, the delamination strength of WC -Co thermal-sprayed coatings under combined torsion and tension is evaluated using a newly developed method, which is called the torsion -tension pin-test. First, the effects of both the pin diameter and the coating thickness on the apparent delamination strength were investigated experimentally. Second, the stress distributions around the interface edge between the pin and the coating were numerically obtained by using the finite element analysis program "MARC." It was confirmed that the fractured plane of the torsion pin coincides with the interfacial plane between the coating and the pin. The apparent delamination strength obtained experimentally decreased linearly with increasing pin diameter and increased with increasing coating thickness t, but it was stable at t of 400 μm or more. The shear delamination strength decreased with increasing tensile stress. Similar stress distributions were observed at the interface when delaminations occurred for rather thick coatings, independent of the pin diameter. The critical combination of the strength of shear stress fields ( Ks) with that of tensile stress fields ( Ka), i.e., the delamination criteria of the coating under combined shear and tensile loadings, was obtained for a WC-12Co thermal-sprayed coating. These combinations were found to be independent of pin diameter and coating thickness.

  5. High-performance graphene/sulphur electrodes for flexible Li-ion batteries using the low-temperature spraying method

    NASA Astrophysics Data System (ADS)

    Kumar, Pushpendra; Wu, Feng-Yu; Hu, Lung-Hao; Ali Abbas, Syed; Ming, Jun; Lin, Chia-Nan; Fang, Jason; Chu, Chih-Wei; Li, Lain-Jong

    2015-04-01

    Elementary sulphur (S) has been shown to be an excellent cathode material in energy storage devices such as Li-S batteries owing to its very high capacity. The major challenges associated with the sulphur cathodes are structural degradation, poor cycling performance and instability of the solid-electrolyte interphase caused by the dissolution of polysulfides during cycling. Tremendous efforts made by others have demonstrated that encapsulation of S materials improves their cycling performance. To make this approach practical for large scale applications, the use of low-cost technology and materials has become a crucial and new focus of S-based Li-ion batteries. Herein, we propose to use a low temperature spraying process to fabricate graphene/S electrode material, where the ink is composed of graphene flakes and the micron-sized S particles prepared by grinding of low-cost S powders. The S particles are found to be well hosted by highly conductive graphene flakes and consequently superior cyclability (~70% capacity retention after 250 cycles), good coulombic efficiency (~98%) and high capacity (~1500 mA h g-1) are obtained. The proposed approach does not require high temperature annealing or baking; hence, another great advantage is to make flexible Li-ion batteries. We have also demonstrated two types of flexible batteries using sprayed graphene/S electrodes.Elementary sulphur (S) has been shown to be an excellent cathode material in energy storage devices such as Li-S batteries owing to its very high capacity. The major challenges associated with the sulphur cathodes are structural degradation, poor cycling performance and instability of the solid-electrolyte interphase caused by the dissolution of polysulfides during cycling. Tremendous efforts made by others have demonstrated that encapsulation of S materials improves their cycling performance. To make this approach practical for large scale applications, the use of low-cost technology and materials has become

  6. Remotely controlled spray gun

    NASA Technical Reports Server (NTRS)

    Cunningham, William C. (Inventor)

    1987-01-01

    A remotely controlled spray gun is described in which a nozzle and orifice plate are held in precise axial alignment by an alignment member, which in turn is held in alignment with the general outlet of the spray gun by insert. By this arrangement, the precise repeatability of spray patterns is insured.

  7. TG-DSC-FTIR Analysis of Cyanobacteria Pyrolysis

    NASA Astrophysics Data System (ADS)

    Supeng, Luo; Guirong, Bao; Hua, Wang; Fashe, Li; Yizhe, Li

    Pyrolysis of cyanobacteria from Dianchi lake was investigated by TG-DSC-FTIR analysis at different heating rates (10, 20, 40°C/min). The results indicated that the pyrolysis of cyanobacteria can be divided into four stages: evaporation, depolymerization, devolatilization and carbonization. Meanwhile, the initial weight-loss temperature, weight-loss extreme position, endothermic and exothermic peaks were moved to higher temperature with the increaseing of the heating rate. The kinetic analysis was made with Popescu method. It indicated that the best kinetic model for the pyrolysis of cyanobacteria was the cylindrical symmetry of the phase boundary reaction model. The main pyrolysis gases checked with real-time online FTIR were HCN, NH3, CO, CO2, water vapor and hydrocarbons.

  8. Spatial distribution visualization of PWM continuous variable-rate spray

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chemical application is a dynamic spatial distribution process, during which spray liquid covers the targets with certain thickness and uniformity. Therefore, it is important to study the 2-D and 3-D (dimensional) spray distribution to evaluate spraying quality. The curve-surface generation methods ...

  9. Corrosivity Of Pyrolysis Oils

    SciTech Connect

    Keiser, James R; Bestor, Michael A; Lewis Sr, Samuel Arthur; Storey, John Morse

    2011-01-01

    Pyrolysis oils from several sources have been analyzed and used in corrosion studies which have consisted of exposing corrosion coupons and stress corrosion cracking U-bend samples. The chemical analyses have identified the carboxylic acid compounds as well as the other organic components which are primarily aromatic hydrocarbons. The corrosion studies have shown that raw pyrolysis oil is very corrosive to carbon steel and other alloys with relatively low chromium content. Stress corrosion cracking samples of carbon steel and several low alloy steels developed through-wall cracks after a few hundred hours of exposure at 50 C. Thermochemical processing of biomass can produce solid, liquid and/or gaseous products depending on the temperature and exposure time used for processing. The liquid product, known as pyrolysis oil or bio-oil, as produced contains a significant amount of oxygen, primarily as components of water, carboxylic acids, phenols, ketones and aldehydes. As a result of these constituents, these oils are generally quite acidic with a Total Acid Number (TAN) that can be around 100. Because of this acidity, bio-oil is reported to be corrosive to many common structural materials. Despite this corrosive nature, these oils have the potential to replace some imported petroleum. If the more acidic components can be removed from this bio-oil, it is expected that the oil could be blended with crude oil and then processed in existing petroleum refineries. The refinery products could be transported using customary routes - pipelines, barges, tanker trucks and rail cars - without a need for modification of existing hardware or construction of new infrastructure components - a feature not shared by ethanol.

  10. Low VOC, Plural Component Spray (PCS) Coatings Program

    DTIC Science & Technology

    2009-05-07

    Continuous Application Method Plural Component Spray Benefits • Automated proportioning • Precision mixing • Utilizes HVLP spray guns • Accommodates...255 - 3541 roddy.keish@wpafb.af.mil Birthplace, Home and Future of Aerospace Low VOC, Plural Component Spray (PCS) Coatings Program 7 May 2009 Report...2009 2. REPORT TYPE 3. DATES COVERED 00-00-2009 to 00-00-2009 4. TITLE AND SUBTITLE Low VOC, Plural Component Spray (PCS) Coatings Program 5a

  11. Vapor phase pyrolysis

    NASA Technical Reports Server (NTRS)

    Steurer, Wolfgang

    1992-01-01

    The vapor phase pyrolysis process is designed exclusively for the lunar production of oxygen. In this concept, granulated raw material (soil) that consists almost entirely of metal oxides is vaporized and the vapor is raised to a temperature where it dissociates into suboxides and free oxygen. Rapid cooling of the dissociated vapor to a discrete temperature causes condensation of the suboxides, while the oxygen remains essentially intact and can be collected downstream. The gas flow path and flow rate are maintained at an optimum level by control of the pressure differential between the vaporization region and the oxygen collection system with the aid of the environmental vacuum.

  12. Comparative pyrolysis studies of ethylarsines

    NASA Astrophysics Data System (ADS)

    Li, S. H.; Larsen, C. A.; Stringfellow, G. B.

    1991-01-01

    The pyrolysis of triethylarsine (TEAs), diethylarsine (DEAsH), and monoethylarsine (MEAsH 2) has been studied at atmospheric pressure in a flow tube reactor using mass spectrometry. He and D 2 were selected as the carrier gases to determine ambient effects and to isotopically label the pyrolysis products. For some experiments, supplemental C 2H 5 and CH 3 radicals, produced from pyrolysis of the co-reactants azoethane ((C 2H 5) 2N 2) and azomethane ((CH 3) 2N 2), were added to investigate the roles of C 2H 5 and CH 3 in the reactions. Significant D 2 effects have been observed for pyrolysis of TEAs but not for DEAsH and MEAsH 2. Pyrolysis of the latter could be enhanced by adding C 2H 5 radicals while the TEAs was nearly unaffected. With the presence of supplemental CH 3 radicals, 85% decomposition was induced for each precursor. The products included DEAsD, rather than DEAsH, for TEAs pyrolysis in D 2. However, DEAsH pyrolysis produced TEAs, and MEAsH 2 decomposed to yield DEAsH and arsine, in both ambients. This suggests that a β-elimination reaction is not a major step for any of the ethylarsine precursors. More likely, radical reactions occur. When trimethylgallium (TMGa) was added, the ethylarsine pyrolysis rates were accelerated due to the CH 3 radicals produced from TMGa pyrolysis. In addition, heterogeneous reactions have been observed for pyrolysis of ethylarsines, especially when a GaAs surface was involved.

  13. Kinetics of scrap tyre pyrolysis under vacuum conditions

    SciTech Connect

    Lopez, Gartzen; Aguado, Roberto; Olazar, Martin Arabiourrutia, Miriam; Bilbao, Javier

    2009-10-15

    Scrap tyre pyrolysis under vacuum is attractive because it allows easier product condensation and control of composition (gas, liquid and solid). With the aim of determining the effect of vacuum on the pyrolysis kinetics, a study has been carried out in thermobalance. Two data analysis methods have been used in the kinetic study: (i) the treatment of experimental data of weight loss and (ii) the deconvolution of DTG (differential thermogravimetry) curve. The former allows for distinguishing the pyrolysis of the three main components (volatile components, natural rubber and styrene-butadiene rubber) according to three successive steps. The latter method identifies the kinetics for the pyrolysis of individual components by means of DTG curve deconvolution. The effect of vacuum in the process is significant. The values of activation energy for the pyrolysis of individual components of easier devolatilization (volatiles and NR) are lower for pyrolysis under vacuum with a reduction of 12 K in the reaction starting temperature. The kinetic constant at 503 K for devolatilization of volatile additives at 0.25 atm is 1.7 times higher than that at 1 atm, and that corresponding to styrene-butadiene rubber at 723 K is 2.8 times higher. Vacuum enhances the volatilization and internal diffusion of products in the pyrolysis process, which contributes to attenuating the secondary reactions of the repolymerization and carbonization of these products on the surface of the char (carbon black). The higher quality of carbon black is interesting for process viability. The large-scale implementation of this process in continuous mode requires a comparison to be made between the economic advantages of using a vacuum and the energy costs, which will be lower when the technologies used for pyrolysis require a lower ratio between reactor volume and scrap tyre flow rate.

  14. Characterization of sprays

    NASA Technical Reports Server (NTRS)

    Chigier, N.; Mao, C.-P.

    1984-01-01

    It is pointed out that most practical power generation and propulsion systems involve the burning of different types of fuel sprays, taking into account aircraft propulsion, industrial furnaces, boilers, gas turbines, and diesel engines. There has been a lack of data which can serve as a basis for spray model development and validation. A major aim of the present investigation is to fill this gap. Experimental apparatus and techniques for studying the characteristics of fuel sprays are discussed, taking into account two-dimensional still photography, cinematography, holography, a laser diffraction particle sizer, and a laser anemometer. The considered instruments were used in a number of experiments, taking into account three different types of fuel spray. Attention is given to liquid fuel sprays, high pressure pulsed diesel sprays, and coal-water slurry sprays.

  15. Low cost sprayed CdTe solar cell research

    NASA Astrophysics Data System (ADS)

    Squillante, M.; Turcotte, R.; Lis, S.; Serreze, H. B.; Entine, G.

    1980-06-01

    Experiments were carried out to optimize the conditions of the chemical reaction and the physical parameters of the spray process in order to produce high quality CdTe thin films. Films containing 95% or more of CdTe were produced by the reaction of (MH4) 2TeO4 with cadmium salts in the presence of a reducing agent. The physical quality of the films improved so that recent ones have been smoother and more uniform. Furthermore, photoconductive effects were observed in many of the films. This progress is partly due to the removal of oxygen by an efficient purge of the spray box and partly due to an increased understanding and control of the spray pyrolysis process.

  16. Status of Process Development for Pyrolysis of Biomass for Liquid Fuels and Chemicals Production.

    SciTech Connect

    Elliott, Douglas C.

    2010-06-01

    Pyrolysis is one of several thermochemical conversion strategies to produce useful fuels from biomass material . The goal of fast pyrolysis is to maximize liquid product yield. Fast pyrolysis is accomplished by the thermal treatment of the biomass in an air-free environment. Very short heat up and cool-down is a requirement for fast pyrolysis. The typical residence time in the pyrolysis reactor is 1 second. In order to accomplish the fast heatup, grinding the biomass to a small particle size in the range of 1 mm is typical and pre-drying of the biomass to less than 10 weight percent moisture is considered the standard. Recovery of the product liquid, called bio-oil, is accomplished by a variety of methods all of which require a quick quench of the product vapor. A definition of fast pyrolysis bio-oil is provided for the CAS # RN 1207435-39-9 recently issued by ChemAbstracts Services.

  17. Dual Core-Shell Structured Si@SiOx@C Nanocomposite Synthesized via a One-Step Pyrolysis Method as a Highly Stable Anode Material for Lithium-Ion Batteries.

    PubMed

    Jiang, Bolun; Zeng, Shi; Wang, Hui; Liu, Daotan; Qian, Jiangfeng; Cao, Yuliang; Yang, Hanxi; Ai, Xinping

    2016-11-23

    Silicon (Si) has been regarded as a promising high-capacity anode material for developing advanced lithium-ion batteries (LIBs), but the practical application of Si anodes is still unsuccessful mainly due to the insufficient cyclability. To deal with this issue, we propose a new route to construct a dual core-shell structured Si@SiOx@C nanocomposite by direct pyrolysis of poly(methyl methacrylate) (PMMA) polymer on the surface of Si nanoparticles. Since the PMMA polymers can be chemically bonded on the nano-Si surface through the interaction between ester group and Si surface group, and thermally decomposed in the subsequent pyrolysis process with their alkyl chains converted to carbon and the residue oxygen recombining with Si to form SiOx, the dual core-shell structure can be conveniently formed in a one-step procedure. Benefiting from the strong buffering effect of the SiOx interlayer and the efficient blocking action of dense outer carbon layer in preventing electrolyte permeation, the obtained nanocomposite demonstrates a high capacity of 1972 mA h g(-1), a stable cycling performance with a capacity retention of >1030 mA h g(-1) over 500 cycles, and particularly a superiorly high Coulombic efficiency of >99.5% upon extended cycling, exhibiting a great promise for practical uses. More importantly, the synthetic method proposed in this work is facile and low cost, making it more suitable for large-scale production of high capacity anode for advanced LIBs.

  18. Cheap carbon sorbents produced from lignite by catalytic pyrolysis

    SciTech Connect

    Kuznetsov, B.N.; Schchipko, M.L.

    1995-12-01

    Some data are presented describing the new technology of carbon sorbent production from powdered lignite in the installation with fluidized bed of catalyst. It was shown the different types of char products with extended pore structure and high sorption ability can be produced from cheap and accessible lignite of Kansk-Achinsk coal pit in pilot installation with fluidized bed of Al-Cu-Cr oxide catalyst or catalytically active slag materials. In comparison with the conventional technologies of pyrolysis the catalytic pyrolysis allows to increase by 3-5 times the process productivity and to decrease significantly the formation of harmful compounds. The latter is accomplished by complete oxidation of gaseous pyrolysis products in the presence of catalysts and by avoiding the formation of pyrolysis tars - the source of cancerogenic compounds. The technology of cheap powdered sorbent production from lignites makes possible to obtain from lignite during the time of pyrolysis only a few seconds char products with porosity up to 0.6 cm{sup 3} /g, and specific surface area more than 400 m{sup 3} /g. Some methods of powdered chars molding into carbon materials with the different shape were proved for producing of firmness sorbents. Cheap carbon sorbents obtained by thermocatalytic pyrolysis can be successfully used in purification of different industrial pollutants as one-time sorbent or as adsorbents of long-term application with periodic regeneration.

  19. Fast Pyrolysis of Agricultural Wastes in a Fluidized Bed Reactor

    NASA Astrophysics Data System (ADS)

    Wang, X. H.; Chen, H. P.; Yang, H. P.; Dai, X. M.; Zhang, S. H.

    Solid biomass can be converted into liquid fuel through fast pyrolysis, which is convenient to be stored and transported with potential to be used as a fossil oil substitute. In China, agricultural wastes are the main biomass materials, whose pyrolysis process has not been researched adequately compared to forestry wastes. As the representative agricultural wastes in China, peanut shell and maize stalk were involved in this paper and pine wood sawdust was considered for comparing the different pyrolysis behaviors of agricultural wastes and forestry wastes. Fast pyrolysis experiments were carried out in a bench-scale fluidized-bed reactor. The bio-oil yieldsof peanut shell and maize stalk were obviously lower than that ofpine sawdust. Compared with pine sawdust, the char yields of peanut shell and maize stalk were higher but the heating value of uncondensable gaswas lower. This means that the bio-oil cost will be higher for agricultural wastes if taking the conventional pyrolysis technique. And the characteristic and component analysis resultsof bio-oil revealed that the quality of bio-oil from agricultural wastes, especially maize stalk, was worse than that from pine wood. Therefore, it is important to take some methods to improve the quality of bio-oilfrom agricultural wastes, which should promote the exploitation of Chinese biomass resources through fast pyrolysis in afluidized bed reactor.

  20. Effect of pyrolysis temperature on toxicity of gases from a polyethylene polymer

    NASA Technical Reports Server (NTRS)

    Hilado, C. J.; Kosola, K. L.

    1978-01-01

    A polyethylene polymer was evaluated for time of toxic effect to occur as the result of exposure to gases generated by pyrolysis at various temperatures, using the toxicity screening test method developed at the University of San Francisco. Times to various animal responses decreased with increasing pyrolysis temperature over the range from 400 C to 800 C. Responses at a pyrolysis temperature of 350 C were more rapid than would be expected from the other data, and may indicate the predominance of different pyrolysis reactions in this particular temperature region.

  1. Concentration-response data on toxicity of pyrolysis gases from some natural and synthetic polymers

    NASA Technical Reports Server (NTRS)

    Hilado, C. J.; Huttlinger, N. V.

    1978-01-01

    Concentration-response data are presented on the toxic effects of the pyrolysis gases from some natural and synthetic polymers, using the toxicity screening test method developed at the University of San Francisco. The pyrolysis gases from wool, red oak, Douglas fir, polycaprolactam, polyether sulfone, polyaryl sulfone, and polyphenylene sulfide appeared to exhibit the concentration-response relationships commonly encountered in toxicology. Carbon monoxide seemed to be an important toxicant in the pyrolysis gases from red oak, Douglas fir, and polycaprolactam, but did not appear to have been the principal toxicant in the pyrolysis gases from polyether sulfone and polyphenylene sulfide.

  2. Pyrolysis and dehalogenation of plastics from waste electrical and electronic equipment (WEEE): a review.

    PubMed

    Yang, Xiaoning; Sun, Lushi; Xiang, Jun; Hu, Song; Su, Sheng

    2013-02-01

    Plastics from waste electrical and electronic equipment (WEEE) have been an important environmental problem because these plastics commonly contain toxic halogenated flame retardants which may cause serious environmental pollution, especially the formation of carcinogenic substances polybrominated dibenzo dioxins/furans (PBDD/Fs), during treat process of these plastics. Pyrolysis has been proposed as a viable processing route for recycling the organic compounds in WEEE plastics into fuels and chemical feedstock. However, dehalogenation procedures are also necessary during treat process, because the oils collected in single pyrolysis process may contain numerous halogenated organic compounds, which would detrimentally impact the reuse of these pyrolysis oils. Currently, dehalogenation has become a significant topic in recycling of WEEE plastics by pyrolysis. In order to fulfill the better resource utilization of the WEEE plastics, the compositions, characteristics and dehalogenation methods during the pyrolysis recycling process of WEEE plastics were reviewed in this paper. Dehalogenation and the decomposition or pyrolysis of WEEE plastics can be carried out simultaneously or successively. It could be 'dehalogenating prior to pyrolysing plastics', 'performing dehalogenation and pyrolysis at the same time' or 'pyrolysing plastics first then upgrading pyrolysis oils'. The first strategy essentially is the two-stage pyrolysis with the release of halogen hydrides at low pyrolysis temperature region which is separate from the decomposition of polymer matrixes, thus obtaining halogenated free oil products. The second strategy is the most common method. Zeolite or other type of catalyst can be used in the pyrolysis process for removing organohalogens. The third strategy separate pyrolysis and dehalogenation of WEEE plastics, which can, to some degree, avoid the problem of oil value decline due to the use of catalyst, but obviously, this strategy may increase the cost of

  3. Supercritical water pyrolysis of sewage sludge.

    PubMed

    Ma, Wenchao; Du, Guiyue; Li, Jian; Fang, Yuanhao; Hou, Li'an; Chen, Guanyi; Ma, Degang

    2017-01-01

    Municipal sewage sludge (SS) from wastewater treatment plant containing high water content (>85wt.%), lead to the difficulty of co-combustion with MSW or coal due to the high cost of drying. This study explores an alternative method by supercritical water (SCW) pyrolysis of sewage sludge (SS) in a high pressure reaction vessel. The effects of temperature and moisture content of SS on yield and composition of the products (bio-oil, bio char and non-condensable gas) were studied. A temperature of 385°C and moisture content of 85wt.% were found to be the optimum conditions for the maximum bio-oil production of 37.23wt.%, with a higher heating value of 31.08MJ/kg. In the optimum condition, the yields of aliphatic hydrocarbon and phenols were about 29.23wt.% and 12.51wt.%, respectively. The physical and chemical properties of bio-char were analyzed by using XRF and BET. Results of GC analyses of NCG showed that it has the maximum HHV of 13.39MJ/m(3) at 445°C and moisture content of 85wt.%. The reaction path from SS to bio-oil through SCW pyrolysis was given. Moreover, carbon balance was calculated for the optimal condition, and finding out that 64.27wt.% of the carbon content was transferred from SS to bio-oil. Finally, this work demonstrates that the SCW pyrolysis is a promising disposal method for SS.

  4. Method of creating starch-like ultra-fine rice flour and effect of spray drying on formation of free fatty acid.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice flour from long, medium, and short grain cultivars were processed by passing a 32% rice flour slurry through a microfluidizer at 100 MPa, and spray dryer at three different outlet temperatures, OT (50°C, 80°C, and 115°C). Spray drying conditions were controlled by the flow-rate of the slurry ...

  5. Low-temperature growth and physical investigations of undoped and (In, Co) doped ZnO thin films sprayed on PEI flexible substrate

    NASA Astrophysics Data System (ADS)

    Ben Ameur, S.; Barhoumi, A.; Mimouni, R.; Amlouk, M.; Guermazi, H.

    2015-08-01

    ZnO thin films were deposited on polymer substrate Polyethyerimide (PEI) at 250 °C by spray pyrolysis technique. The effects of different doping elements (Co and In) on physical properties of ZnO thin films were investigated. Thin film characterizations were carried out using X-ray diffraction technique, UV-Vis-NIR spectroscopy, Photoluminescence (PL) spectroscopy and the contact angle measurement method. XRD measurement showed a successful growth of crystalline films on polymer substrate at low temperature by the spray pyrolysis process. XRD patterns revealed that all films consist of single ZnO phase and were well crystallized with preferential orientation towards (1 0 1) direction. Doping by cobalt has effective role in the enhancement of the crystalline quality, increases in the band gap according to Burstein Moss effect. Doping with indium leads rather to the decrease of both crystallinity and optical band gap energy value. Photoluminescence of the films showed UV emission (NBE) and visible emission related to defects. The contact angles were measured to study the effect of various doping elements on the hydrophobicity of the film depending on surface roughness. Results showed strong dependence on the doping element. In fact, doping with cobalt element increases the roughness of ZnO films and reinforces the surface from hydrophilic to hydrophobic (θ > 90°).

  6. Chapter 8: Biomass Pyrolysis Oils

    SciTech Connect

    McCormick, Robert L.; Baldwin, Robert M.; Arbogast, Stephen; Bellman, Don; Paynter, Dave; Wykowski, Jim

    2016-09-06

    Fast pyrolysis is heating on the order of 1000 degrees C/s in the absence of oxygen to 40-600 degrees C, which causes decomposition of the biomass. Liquid product yield from biomass can be as much as 80% of starting dry weight and contains up to 75% of the biomass energy content. Other products are gases, primarily carbon monoxide, carbon dioxide, and methane, as well as solid char and ash. Residence time in the reactor is only 0.5-2 s so that relatively small, low-capital-cost reactors can be used. The low capital cost combined with greenhouse gas emission reductions relative to petroleum fuels of 50-95% makes pyrolysis an attractive process. The pyrolysis liquids have been investigated as a refinery feedstock and as stand-alone fuels. Utilization of raw pyrolysis oil has proven challenging. The organic fraction is highly corrosive because of its high organic acid content. High water content lowers the net heating value and can increase corrosivity. It can be poorly soluble in petroleum or petroleum products and can readily absorb water. Distillation residues can be as high as 50%, viscosity can be high, oils can exhibit poor stability in storage, and they can contain suspended solids. The ignition quality of raw pyrolysis oils is poor, with cetane number estimates ranging from 0 to 35, but more likely to be in the lower end of that range. While the use of raw pyrolysis oils in certain specific applications with specialized combustion equipment may be possible, raw oils must be significantly upgraded for use in on-highway spark-ignition (SI) and compression-ignition (CI) engines. Upgrading approaches most often involve catalytic hydrodeoxygenation, one of a class of reactions known as hydrotreating or hydroprocessing. This chapter discusses the properties of raw and upgraded pyrolysis oils, as well as the potential for integrating biomass pyrolysis with a petroleum refinery to significantly reduce the hydroprocessing cost.

  7. Pyrolysis characteristics of the mixture of printed circuit board scraps and coal powder.

    PubMed

    Hao, Juan; Wang, Haifeng; Chen, Shuhe; Cai, Bin; Ge, Linhan; Xia, Wencheng

    2014-10-01

    Thermogravimetric (TG) analysis and infrared spectroscopy were used to analyze the pyrolysis characteristics of printed circuit board scraps (PCBs), coal powder and their mixtures under nitrogen atmosphere. The experimental results show that there is a large difference between waste PCBs and coal powder in pyrolysis processing. The pyrolysis properties of the mixing samples are the result of interaction of the PCBs and coal powder, which is influenced by the content of mixture. The degree of pyrolysis and pyrolysis properties of the mixture are much better than that of the single component. The TG and the differential thermogravimetric (DTG) curves of the PCBs mixed with coal powder move towards the high-temperature zone with increasing amount of coal powder and subsequently the DTG peak also becomes wider. The Coats-Redfern integral method was used to determine the kinetic parameters of pyrolysis reaction mechanism with the different proportion of mixture. The gas of pyrolysis mainly composes of CO2, CO, H2O and some hydrocarbon. The bromide characteristic absorption peak has been detected obviously in the pyrolysis gas of PCBs. On the contrary, the absorption peak of the bromide is not obvious in pyrolysis gas of the PCBs samples adding 40% coal powder.

  8. Bear Spray Safety Program

    USGS Publications Warehouse

    Blome, C.D.; Kuzniar, R.L.

    2009-01-01

    A bear spray safety program for the U.S. Geological Survey (USGS) was officially initiated by the Firearms Safety Committee to address accident prevention and to promote personnel training in bear spray and its transportation, storage, and use for defense against wild animals. Used as part of a system including firearms, or used alone for those who choose not to carry a firearm, bear spray is recognized as an effective tool that can prevent injury in a wild animal attack.

  9. Flash Pyrolysis and Fractional Pyrolysis of Oleaginous Biomass in a Fluidized-bed Reactor

    NASA Astrophysics Data System (ADS)

    Urban, Brook

    Thermochemical conversion methods such as pyrolysis have the potential for converting diverse biomass feedstocks into liquid fuels. In particular, bio-oil yields can be maximized by implementing flash pyrolysis to facilitate rapid heat transfer to the solids along with short vapor residence times to minimize secondary degradation of bio-oils. This study first focused on the design and construction of a fluidized-bed flash pyrolysis reactor with a high-efficiency bio-oil recovery unit. Subsequently, the reactor was used to perform flash pyrolysis of soybean pellets to assess the thermochemical conversion of oleaginous biomass feedstocks. The fluidized bed reactor design included a novel feed input mechanism through suction created by flow of carrier gas through a venturi which prevented plugging problems that occur with a more conventional screw feeders. In addition, the uniquely designed batch pyrolysis unit comprised of two tubes of dissimilar diameters. The bottom section consisted of a 1" tube and was connected to a larger 3" tube placed vertically above. At the carrier gas flow rates used in these studies, the feed particles remained fluidized in the smaller diameter tube, but a reduction in carrier gas velocity in the larger diameter "disengagement chamber" prevented the escape of particles into the condensers. The outlet of the reactor was connected to two Allihn condensers followed by an innovative packed-bed dry ice condenser. Due to the high carrier gas flow rates in fluidized bed reactors, bio-oil vapors form dilute aerosols upon cooling which that are difficult to coalesce and recover by traditional heat exchange condensers. The dry ice condenser provided high surface area for inertial impaction of these aerosols and also allowed easy recovery of bio-oils after natural evaporation of the dry ice at the end of the experiments. Single step pyrolysis was performed between 250-610°C with a vapor residence time between 0.3-0.6s. At 550°C or higher, 70% of

  10. Catalytic and non-catalytic pyrolysis of biomass in non-inert environments for production of deoxygenated bio-oil and chemicals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fast pyrolysis processes are among the most effective methods for liquefaction of lignocellulosic biomass. Catalytic fast pyrolysis (CFP) over HZSM-5 or other zeolites and/or utilization of reactive atmospheres such as in the non-catalytic Tail Gas Reactive Pyrolysis (TRGP) process, a recent patent...

  11. Immobilized TiO2 nanoparticles produced by flame spray for photocatalytic water remediation

    NASA Astrophysics Data System (ADS)

    Bettini, Luca Giacomo; Diamanti, Maria Vittoria; Sansotera, Maurizio; Pedeferri, Maria Pia; Navarrini, Walter; Milani, Paolo

    2016-08-01

    Anatase/rutile mixed-phase titanium dioxide (TiO2) photocatalysts in the form of nanostructured powders with different primary particle size, specific surface area, and rutile content were produced from the gas-phase by flame spray pyrolysis (FSP) starting from an organic solution containing titanium (IV) isopropoxide as Ti precursor. Flame spray-produced TiO2 powders were characterized by means of X-ray diffraction, Raman spectroscopy, and BET measurements. As-prepared powders were mainly composed of anatase crystallites with size ranging from 7 to 15 nm according to the synthesis conditions. TiO2 powders were embedded in a multilayered fluoropolymeric matrix to immobilize the nanoparticles into freestanding photocatalytic membranes. The photocatalytic activity of the TiO2-embedded membranes toward the abatement of hydrosoluble organic pollutants was evaluated employing the photodegradation of rhodamine B in aqueous solution as test reaction. The photoabatement rate of best performing membranes significantly overcomes that of membranes produced by the same method and incorporating commercial P25-TiO2.

  12. Investigation of structural, optical, electrical and dielectric properties of catalytic sprayed hausmannite thin film

    SciTech Connect

    Larbi, T.; Ouni, B.; Boukhachem, A.; Boubaker, K. Amlouk, M.

    2014-12-15

    Hausmannite Mn{sub 3}O{sub 4} thin film have been synthesized using spray pyrolysis method. These films are characterized using X-ray diffraction (XRD), atomic force microscope AFM, UV–vis–NIR spectroscopy and impedance spectroscopy. XRD study confirms the tetragonal structure of the as-deposited films with lattice parameters, a = 5.1822 Å and c = 9.4563 Å and a grain size of about 56 nm. UV–vis–NIR spectroscopy was further used to estimate optical constants such as extinction coefficient, refractive index, band gap and Urbach energy. Moreover, impedance spectroscopy analysis was employed to estimate electrical and dielectrical properties of the sprayed thin films. The activation energy values deduced from DC conductivity and relaxation frequency were almost the same, revealing that the transport phenomena is thermally activated by hopping between localized states. The AC conductivity is found to be proportional to ω{sup s}. The temperature dependence of the AC conductivity and the frequency exponent, s was reasonably well interpreted in terms of the correlated barrier-hopping CBH model. The dielectric properties were sensitive to temperature and frequency. The study of the electrical modulus indicated that the charge carrier was localized. Experimental results concerning optical constants as Urbach energy, dielectric constant, electric modulus and AC and DC conductivity were discussed in terms of the hopping model as suggested by Elliott.

  13. Catalytic cracking of fast and tail gas reactive pyrolysis bio-oils over HZSM-5

    Technology Transfer Automated Retrieval System (TEKTRAN)

    While hydrodeoxygenation (HDO) of pyrolysis oil is well understood as an upgrading method, the high processing pressures associated with it alone justify the exploration of alternative upgrading solutions, especially those that could adapt pyrolysis oils into the existing refinery infrastructure. Ca...

  14. Plasma Pyrolysis Assembly Regeneration Evaluation

    NASA Technical Reports Server (NTRS)

    Medlen, Amber; Abney, Morgan B.; Miller, Lee A.

    2011-01-01

    In April 2010 the Carbon Dioxide Reduction Assembly (CRA) was delivered to the International Space Station (ISS). This technology requires hydrogen to recover oxygen from carbon dioxide. This results in the production of water and methane. Water is electrolyzed to provide oxygen to the crew. Methane is vented to space resulting in a loss of valuable hydrogen and unreduced carbon dioxide. This is not critical for ISS because of the water resupply from Earth. However, in order to have enough oxygen for long-term missions, it will be necessary to recover the hydrogen to maximize oxygen recovery. Thus, the Plasma Pyrolysis Assembly (PPA) was designed to recover hydrogen from methane. During operation, the PPA produces small amounts of carbon that can ultimately reduce performance by forming on the walls and windows of the reactor chamber. The carbon must be removed, although mechanical methods are highly inefficient, thus chemical methods are of greater interest. The purpose of this effort was to determine the feasibility of chemically removing the carbon from the walls and windows of a PPA reactor using a pure carbon dioxide stream.

  15. Spray-formed tooling and aluminum strip

    SciTech Connect

    McHugh, K.M.

    1995-11-01

    Spray forming is an advanced materials processing technology that converts a bulk liquid metal to a near-net-shape solid by depositing atomized droplets onto a suitably shaped substrate. By combining rapid solidification processing with product shape control, spray forming can reduce manufacturing costs while improving product quality. De Laval nozzles offer an alternative method to the more conventional spray nozzle designs. Two applications are described: high-volume production of aluminum alloy strip, and the production of specialized tooling, such as injection molds and dies, for rapid prototyping.

  16. LSPRAY-IV: A Lagrangian Spray Module

    NASA Technical Reports Server (NTRS)

    Raju, M. S.

    2012-01-01

    LSPRAY-IV is a Lagrangian spray solver developed for application with parallel computing and unstructured grids. It is designed to be massively parallel and could easily be coupled with any existing gas-phase flow and/or Monte Carlo Probability Density Function (PDF) solvers. The solver accommodates the use of an unstructured mesh with mixed elements of either triangular, quadrilateral, and/or tetrahedral type for the gas flow grid representation. It is mainly designed to predict the flow, thermal and transport properties of a rapidly vaporizing spray. Some important research areas covered as a part of the code development are: (1) the extension of combined CFD/scalar-Monte- Carlo-PDF method to spray modeling, (2) the multi-component liquid spray modeling, and (3) the assessment of various atomization models used in spray calculations. The current version contains the extension to the modeling of superheated sprays. The manual provides the user with an understanding of various models involved in the spray formulation, its code structure and solution algorithm, and various other issues related to parallelization and its coupling with other solvers.

  17. Measuring Spray Droplet Size from Agricultural Nozzles Using Laser Diffraction

    PubMed Central

    Fritz, Bradley K.; Hoffmann, W. Clint

    2016-01-01

    When making an application of any crop protection material such as an herbicide or pesticide, the applicator uses a variety of skills and information to make an application so that the material reaches the target site (i.e., plant). Information critical in this process is the droplet size that a particular spray nozzle, spray pressure, and spray solution combination generates, as droplet size greatly influences product efficacy and how the spray moves through the environment. Researchers and product manufacturers commonly use laser diffraction equipment to measure the spray droplet size in laboratory wind tunnels. The work presented here describes methods used in making spray droplet size measurements with laser diffraction equipment for both ground and aerial application scenarios that can be used to ensure inter- and intra-laboratory precision while minimizing sampling bias associated with laser diffraction systems. Maintaining critical measurement distances and concurrent airflow throughout the testing process is key to this precision. Real time data quality analysis is also critical to preventing excess variation in the data or extraneous inclusion of erroneous data. Some limitations of this method include atypical spray nozzles, spray solutions or application conditions that result in spray streams that do not fully atomize within the measurement distances discussed. Successful adaption of this method can provide a highly efficient method for evaluation of the performance of agrochemical spray application nozzles under a variety of operational settings. Also discussed are potential experimental design considerations that can be included to enhance functionality of the data collected. PMID:27684589

  18. Sprayed lanthanum doped zinc oxide thin films

    NASA Astrophysics Data System (ADS)

    Bouznit, Y.; Beggah, Y.; Ynineb, F.

    2012-01-01

    Lanthanum doped zinc oxide thin films were deposited on soda-lime glass substrates using a pneumatic spray pyrolysis technique. The films were prepared using different lanthanum concentrations at optimum deposition parameters. We studied the variations in structural, morphological and optical properties of the samples due to the change of doping concentration in precursor solutions. X-ray diffraction (XRD) patterns show that pure and La-doped ZnO thin films are highly textured along c-axis perpendicular to the surface of the substrate. Scanning electron micrographs show that surface morphology of ZnO films undergoes a significant change according to lanthanum doping. All films exhibit a transmittance higher than 80% in the visible region.

  19. Fluidic spray control

    NASA Astrophysics Data System (ADS)

    Tseng, Kuo-Tung

    An original fluidic control method in an axisymmetric spray orifice is investigated using both experiments and existing CFD. Cavitation images, droplet size measurements, discharge coefficient, unsteadiness measurements and CFD are incorporated to find out the causes resulting in small droplets. A flow rig delivering pressurized water flow to an orifice is constructed. A secondary flow is introduced through an annular slot in the orifice wall to control the cavitation, and thus the spray, at pressures up to 550 kPa driving pressure difference. The orifice used is nominally axisymmetric with a diameter 0.81 mm and length 5.08 mm. Two types of orifices are made. Orifice 1 has the slot located 0.81 mm below the orifice inlet, and the slot orientation is angled at 67.5° to the hole axis. Orifice 2 has the slot situated at 0.41 mm below the orifice inlet, and the slot orientation is angled at 15° to the hole axis. Devices, including a CCD camera, a particle-sizer and a He-Ne laser system, were utilized for flow visualization and relevant measurements. The cavitation and spray were photographed with a high resolution CCD digital camera. Droplet size measurements were made with a laser diffraction particle-sizer. Moreover, the cavitation frequencies were explored using a He-Ne laser along with a photodiode and an oscilloscope. CFD codes developed by Chen and Heister were used to model the internal flow. 54 cases were run, including 5 slot locations, 5 slot orientations, and 4 secondary flow rates. Compared with the experimental results, the agreement between CFD and experimental results is good except for hydraulic flip. Generally the high pressure region upstream of the slot, the large high pressure variation over time, and the long cavitation length are the favorable conditions for creating small droplets. The CFD together with experimental measurements correlate the flow structures with droplet sizes. Understanding the relationship between flow structures and droplet

  20. Ciclesonide Nasal Spray

    MedlinePlus

    ... Wash the dust cap and applicator with warm water. Dry and replace the applicator and press down and release the pump one time or until you see a fine spray. Replace the dust cap. Do not use pins or other sharp objects in the tiny spray hole on the nasal applicator to remove the blockage. ...

  1. Cold spray nozzle design

    DOEpatents

    Haynes, Jeffrey D.; Sanders, Stuart A.

    2009-06-09

    A nozzle for use in a cold spray technique is described. The nozzle has a passageway for spraying a powder material, the passageway having a converging section and a diverging section, and at least the diverging section being formed from polybenzimidazole. In one embodiment of the nozzle, the converging section is also formed from polybenzimidazole.

  2. Experimental investigation on the characteristics of supersonic fuel spray and configurations of induced shock waves

    PubMed Central

    Wang, Yong; Yu, Yu-song; Li, Guo-xiu; Jia, Tao-ming

    2017-01-01

    The macro characteristics and configurations of induced shock waves of the supersonic sprays are investigated by experimental methods. Visualization study of spray shape is carried out with the high-speed camera. The macro characteristics including spray tip penetration, velocity of spray tip and spray angle are analyzed. The configurations of shock waves are investigated by Schlieren technique. For supersonic sprays, the concept of spray front angle is presented. Effects of Mach number of spray on the spray front angle are investigated. The results show that the shape of spray tip is similar to blunt body when fuel spray is at transonic region. If spray entered the supersonic region, the oblique shock waves are induced instead of normal shock wave. With the velocity of spray increasing, the spray front angle and shock wave angle are increased. The tip region of the supersonic fuel spray is commonly formed a cone. Mean droplet diameter of fuel spray is measured using Malvern’s Spraytec. Then the mean droplet diameter results are compared with three popular empirical models (Hiroyasu’s, Varde’s and Merrigton’s model). It is found that the Merrigton’s model shows a relative good correlation between models and experimental results. Finally, exponent of injection velocity in the Merrigton’s model is fitted with experimental results. PMID:28054555

  3. Experimental investigation on the characteristics of supersonic fuel spray and configurations of induced shock waves

    NASA Astrophysics Data System (ADS)

    Wang, Yong; Yu, Yu-Song; Li, Guo-Xiu; Jia, Tao-Ming

    2017-01-01

    The macro characteristics and configurations of induced shock waves of the supersonic sprays are investigated by experimental methods. Visualization study of spray shape is carried out with the high-speed camera. The macro characteristics including spray tip penetration, velocity of spray tip and spray angle are analyzed. The configurations of shock waves are investigated by Schlieren technique. For supersonic sprays, the concept of spray front angle is presented. Effects of Mach number of spray on the spray front angle are investigated. The results show that the shape of spray tip is similar to blunt body when fuel spray is at transonic region. If spray entered the supersonic region, the oblique shock waves are induced instead of normal shock wave. With the velocity of spray increasing, the spray front angle and shock wave angle are increased. The tip region of the supersonic fuel spray is commonly formed a cone. Mean droplet diameter of fuel spray is measured using Malvern’s Spraytec. Then the mean droplet diameter results are compared with three popular empirical models (Hiroyasu’s, Varde’s and Merrigton’s model). It is found that the Merrigton’s model shows a relative good correlation between models and experimental results. Finally, exponent of injection velocity in the Merrigton’s model is fitted with experimental results.

  4. A rapid and sensitive HPLC-APCI-MS/MS method determination of fluticasone in human plasma: application for a bioequivalency study in nasal spray formulations.

    PubMed

    Byrro, Ricardo Martins Duarte; César, Isabela Costa; de Santana e Silva Cardoso, Fabiana Fernandes; Mundim, Iram Moreira; Teixeira, Leonardo de Souza; Bonfim, Ricardo Rodrigues; Gomes, Sandro Antônio; Pianetti, Gerson Antônio

    2012-03-05

    A sensitive method for the determination of fluticasone in plasma was developed using high performance liquid chromatography with tandem mass spectrometric detection, whereas beclomethasone was used as internal standard. The analytes were extracted with a simple liquid-liquid extraction from the plasma samples and separated on an ACE C(18) 50 × 4.6 mm i.d.; 5 μm particle size column with a mobile phase consisting of acetonitrile - 0.01% formic acid (48:52, v/v) at a flow rate of 1 ml/min. Detection was achieved by an Applied Biosystems API 5000 mass spectrometer (LC-MS/MS) set at unit resolution in the multiple reaction monitoring mode. Atmospheric pressure chemical ionization (APCI) was used for ion production. The mean recovery for fluticasone propionate was 85%, with a lower limit of quantification set at 2 pg/mL. The validated analytical method was applied to a bioequivalence study of fluticasone propionate administered by nasal spray formulations in human volunteers.

  5. Environmentally compatible spray cement

    SciTech Connect

    Loeschnig, P.

    1995-12-31

    Within the framework of a European research project, Heidelberger Zement developed a quickly setting and hardening binder for shotcrete, called Chronolith S, which avoids the application of setting accelerators. Density and strength of the shotcrete produced with this spray cement correspond to those of an unaccelerated shotcrete. An increased hazard for the heading team and for the environment, which may occur when applying setting accelerators, can be excluded here. Owing to the special setting properties of a spray cement, the process engineering for its manufacturing is of great importance. The treatment of a spray cement as a dry concrete with kiln-dried aggregates is possible without any problems. The use of a naturally damp pre-batched mixture is possible with Chronolith S but requires special process engineering; spray cement and damp aggregate are mixed with one another immediately before entering the spraying machinery.

  6. Pyrolysis kinetics of lignocellulosic materials

    SciTech Connect

    Balci, S.; Dogu, T.; Yuecel, H. . Dept. of Chemical Engineering)

    1993-11-01

    Pyrolysis kinetics of almond and hazelnut shells and beech wood were carried out using a thermogravimetric technique. Experiments were repeated for different final pyrolysis temperatures ranging from 300 to 850 C. Approximately 90% of the pyrolysis reactions were completed up to 450 C. The initial values of the activation energy of pyrolysis reaction were found to be around 22 kcal/mol for shells of almond and hazelnut. On the other hand, initial activation energy of beech wood pyrolysis was found as 29.4 kcal/mol. Results indicated that a first-order decomposition in terms of volatile content of the reactant showed good agreement with the data only at the initial stages of the reaction. The reaction rate constant was found to decrease with reaction extent due to the changes in the chemical and physical structure of the solid. Among several models proposed, a model which predicted an increase of activation energy with reaction extent gave the best agreement with the experimental data.

  7. Vitamin D3 supplementation in healthy adults: a comparison between capsule and oral spray solution as a method of delivery in a wintertime, randomised, open-label, cross-over study.

    PubMed

    Todd, Joshua J; McSorley, Emeir M; Pourshahidi, L Kirsty; Madigan, Sharon M; Laird, Eamon; Healy, Martin; Magee, Pamela J

    2016-10-01

    Vitamin D is typically supplied in capsule form, both in trials and in clinical practice. However, little is known regarding the efficacy of vitamin D administered via oral sprays - a method that primarily bypasses the gastrointestinal absorption route. This study aimed to compare the efficacy of vitamin D3 liquid capsules and oral spray solution in increasing wintertime total 25-hydroxyvitamin D (25(OH)D) concentrations. In this randomised, open-label, cross-over trial, healthy adults (n 22) received 3000 IU (75 µg) vitamin D3 daily for 4 weeks in either capsule or oral spray form. Following a 10-week washout phase, participants received the opposite treatment for a final 4 weeks. Anthropometrics and fasted blood samples were obtained before and after supplementation, with samples analysed for total 25(OH)D, creatinine, intact parathyroid hormone and adjusted Ca concentrations. At baseline, vitamin D sufficiency (total 25(OH)D>50 nmol/l), insufficiency (31-49 nmol/l) and clinical deficiency (<30 nmol/l) were evident in 59, 23 and 18 % of the participants, respectively. Overall, baseline total mean 25(OH)D concentration averaged 59·76 (sd 29·88) nmol/l, representing clinical sufficiency. ANCOVA revealed no significant difference in the mean and standard deviation change from baseline in total 25(OH)D concentrations between oral spray and capsule supplementation methods (26·15 (sd 17·85) v. 30·38 (sd 17·91) nmol/l, respectively; F=1·044, adjusted r 2 0·493, P=0·313). Oral spray vitamin D3 is an equally effective alternative to capsule supplementation in healthy adults.

  8. Plasma spray forming metals, intermetallics, and composites

    NASA Astrophysics Data System (ADS)

    Sampath, Sanjay; Herman, Herbert

    1993-07-01

    Plasma spray processing is a droplet deposition method that combines the steps of melting, rapid solidification, and consolidation into a single step. The versatility of the technology enables the processing of freestanding bulk, near-net shapes of a wide range of alloys, intermetallics, ceramics, and composites, while still retaining the benefits of rapid solidification processing. In particular, it is possible to produce dense forms through vacuum plasma spraying.

  9. Spray Rolling Aluminum Strip

    SciTech Connect

    Lavernia, E.J.; Delplanque, J-P; McHugh, K.M.

    2006-05-10

    Spray forming is a competitive low-cost alternative to ingot metallurgy for manufacturing ferrous and non-ferrous alloy shapes. It produces materials with a reduced number of processing steps, while maintaining materials properties, with the possibility of near-net-shape manufacturing. However, there are several hurdles to large-scale commercial adoption of spray forming: 1) ensuring strip is consistently flat, 2) eliminating porosity, particularly at the deposit/substrate interface, and 3) improving material yield. Through this program, a new strip/sheet casting process, termed spray rolling, has been developed, which is an innovative manufacturing technique to produce aluminum net-shape products. Spray rolling combines the benefits of twin-roll casting and conventional spray forming, showing a promising potential to overcome the above hurdles associated with spray forming. Spray rolling requires less energy and generates less scrap than conventional processes and, consequently, enables the development of materials with lower environmental impacts in both processing and final products. Spray Rolling was developed as a collaborative project between the University of California-Davis, the Colorado School of Mines, the Idaho National Engineering and Environmental Laboratory, and an industry team. The following objectives of this project were achieved: (1) Demonstration of the feasibility of the spray rolling process at the bench-scale level and evaluation of the materials properties of spray rolled aluminum strip alloys; and (2) Demonstration of 2X scalability of the process and documentation of technical hurdles to further scale up and initiate technology transfer to industry for eventual commercialization of the process.

  10. An overview of spray drift reduction testing of spray nozzles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The importance of the development and testing of drift reduction technologies (DRTs) is increasing. Common spray drift reduction technologies include spray nozzles and spray adjuvants. Following draft procedures developed for a DRT program, three spray nozzles were tested under high air speed cond...

  11. Experimental Research of Pyrolysis Gases Cracking on Surface of Charcoal

    NASA Astrophysics Data System (ADS)

    Kosov, Valentin; Kosov, Vladimir; Zaichenko, Victor

    For several years, in the Joint Institute for High Temperatures of Russian Academy of Sciences, two-stage technology of biomass processing has been developing [1]. The technology is based on pyrolysis of biomass as the first stage. The second stage is high-temperature conversion of liquid fraction of the pyrolysis on the surface of porous charcoal matrix. Synthesis gas consisted of carbon monoxide and hydrogen is the main products of the technology. This gas is proposed to be used as fuel for gas-engine power plant. For practical implementation of the technology it is important to know the size of hot char filter for full cracking of the pyrolysis gases on the surface of charcoal. Theoretical determination of the cracking parameters of the pyrolysis gases on the surface of coal is extremely difficult because the pyrolysis gases include tars, whose composition and structure is complicated and depends on the type of initial biomass. It is also necessary to know the surface area of the char used in the filter, which is also a difficult task. Experimental determination of the hot char filter parameters is presented. It is shown that proposed experimental method can be used for different types of biomass.

  12. A simplified model of aerosol removal by containment sprays

    SciTech Connect

    Powers, D.A. ); Burson, S.B. . Div. of Safety Issue Resolution)

    1993-06-01

    Spray systems in nuclear reactor containments are described. The scrubbing of aerosols from containment atmospheres by spray droplets is discussed. Uncertainties are identified in the prediction of spray performance when the sprays are used as a means for decontaminating containment atmospheres. A mechanistic model based on current knowledge of the physical phenomena involved in spray performance is developed. With this model, a quantitative uncertainty analysis of spray performance is conducted using a Monte Carlo method to sample 20 uncertain quantities related to phenomena of spray droplet behavior as well as the initial and boundary conditions expected to be associated with severe reactor accidents. Results of the uncertainty analysis are used to construct simplified expressions for spray decontamination coefficients. Two variables that affect aerosol capture by water droplets are not treated as uncertain; they are (1) [open quote]Q[close quote], spray water flux into the containment, and (2) [open quote]H[close quote], the total fall distance of spray droplets. The choice of values of these variables is left to the user since they are plant and accident specific. Also, they can usually be ascertained with some degree of certainty. The spray decontamination coefficients are found to be sufficiently dependent on the extent of decontamination that the fraction of the initial aerosol remaining in the atmosphere, m[sub f], is explicitly treated in the simplified expressions. The simplified expressions for the spray decontamination coefficient are given. Parametric values for these expressions are found for median, 10 percentile, and 90 percentile values in the uncertainty distribution for the spray decontamination coefficient. Examples are given to illustrate the utility of the simplified expressions to predict spray decontamination of an aerosol-laden atmosphere.

  13. 10 CFR 431.264 - Uniform test method for the measurement of flow rate for commercial prerinse spray valves.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... gallons per minute (gpm) or liters per minute (L/min), shall be conducted in accordance with the test... 10 Energy 3 2011-01-01 2011-01-01 false Uniform test method for the measurement of flow rate for... Valves Test Procedures § 431.264 Uniform test method for the measurement of flow rate for...

  14. 10 CFR 431.264 - Uniform test method for the measurement of flow rate for commercial prerinse spray valves.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... gallons per minute (gpm) or liters per minute (L/min), shall be conducted in accordance with the test... 10 Energy 3 2013-01-01 2013-01-01 false Uniform test method for the measurement of flow rate for... Valves Test Procedures § 431.264 Uniform test method for the measurement of flow rate for...

  15. An Optically Accessible Pyrolysis Microreactor

    NASA Astrophysics Data System (ADS)

    Baraban, Joshua H.; David, Donald E.; Ellison, Barney; Daily, John W.

    2016-06-01

    We report an optically accessible pyrolysis micro-reactor suitable for in situ laser spectroscopic measurements. A radiative heating design allows for completely unobstructed views of the micro-reactor along two axes. The maximum temperature demonstrated here is only 1300 K (as opposed to 1700 K for the usual SiC micro-reactor) because of the melting point of fused silica, but alternative transparent materials will allow for higher temperatures. Laser induced fluorescence measurements on nitric oxide are presented as a proof of principle for spectroscopic characterization of pyrolysis conditions. (This work has been published in J. H. Baraban, D. E. David, G. B. Ellison, and J. W. Daily. An Optically Accessible Pyrolysis Micro-Reactor. Review of Scientific Instruments, 87(1):014101, 2016.)

  16. Li EXCESS Li4+xTi5-xO12-δ/C COMPOSITE USING SPRAY-DRYING METHOD AND ITS ELECTRODE PROPERTIES

    NASA Astrophysics Data System (ADS)

    Yoshikawa, Daisuke; Suzuki, Norio; Kadoma, Yoshihiro; Ui, Koichi; Kumagai, Naoaki

    2012-03-01

    We have prepared a lithium excess carbon composite material, Li4+xTi5-xO12-δ/C (LTO/C), using various amounts of sucrose as a carbon source by the spray-drying method. The prepared materials were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and elemental analysis. The prepared material had the Li4Ti5O12 phase including 3.9-18.4 wt.% carbon. Transmission electron microscopy images and the selected area diffraction (SAD) pattern showed that the prepared materials consisted of a carbon nanonetwork in the LTO/C composite. The charge-discharge cycling tests were carried out using the R2032 coin-type cell under the following conditions; 1.2-3.0 V, 0.1 C-10 C (1 C = 175 mA g-1), 25°C. Based on the electrochemical results, the electrode performance of the prepared material was improved with increasing amounts of residual carbon, in particular, LTO/C including 6.2 wt.% residual carbon exhibited the best electrode performance of 156 mAh g-1 at 1 C during 50 cyclings when compared to the other materials.

  17. A novel high-performance liquid chromatography-electron spray ionization-mass spectrometry method for simultaneous determination of guggulsterones, piperine and gallic acid in Triphala guggulu

    PubMed Central

    Muguli, Ganesh; Vadaparthi, P. R. Rao; Ramesh, B.; Gowda, Vishakante; Paramesh, Rangesh; Jadhav, Atul N.; Babu, K. Suresh

    2015-01-01

    “Triphalaguggulu” is an important Ayurvedic formulation comprising of Guggulu, that is, Commiphora wightii (Arn.) Bhandari as a base wherein powdered fruits of triphala, that is, Phyllanthus emblica L., Terminalia bellirica (Gaertn.) Roxb and Terminalia chebula Retz, along with powdered fruit of Piper longum L. are compounded. This polyherbal preparation has been strongly recommended in chronic inflammation, piles, and fistula. However, due to the complexity of compound formulation standardization of commercial products is challenging. In the present communication marker-based standardization of “Triphalaguggulu” preparation using gallic acid (for triphala), piperine (for P. longum L.) and guggulsterones (for guggulu) is reported. These compounds of diverse chemistry were successfully separated on a Waters HR-C18 column by isocratic elution with methanol and water (80:20 v/v) as mobile phase at the flow rate of 1.0 mL/min coupled with photodiode array detector. These optimal chromatographic conditions were used for simultaneous quantification of gallic acid, guggulsterones (E and Z) and piperine in commercial samples by high-performance liquid chromatography-electron spray ionization-mass spectrometry and method was validated as per ICH guidelines. PMID:26109777

  18. Plasma-Sprayed Photocatalytic Zinc Oxide Coatings

    NASA Astrophysics Data System (ADS)

    Navidpour, A. H.; Kalantari, Y.; Salehi, M.; Salimijazi, H. R.; Amirnasr, M.; Rismanchian, M.; Azarpour Siahkali, M.

    2017-03-01

    Fabrication of semiconductor coatings with photocatalytic action for photodegradation of organic pollutants is highly desirable. In this research, pure zinc oxide, which is well known for its promising photocatalytic activity, was deposited on stainless-steel plates by plasma spraying. The phase composition and microstructure of the deposited films were studied by x-ray diffraction analysis and scanning electron microscopy, respectively. Despite the low-energy conditions of the plasma spraying process, the zinc oxide coatings showed good mechanical integrity on the substrate. Their photocatalytic activity was evaluated using aqueous solution of methylene blue at concentration of 5 mg L-1. The results showed the potential of the plasma spraying technique to deposit zinc oxide coatings with photocatalytic action under ultraviolet illumination. Ultraviolet-visible (UV-Vis) diffuse reflectance spectroscopy confirmed that the plasma spraying method could deposit zinc oxide films with higher photoabsorption ability relative to the initial powder.

  19. Toxicity of pyrolysis gases from wood

    NASA Technical Reports Server (NTRS)

    Hilado, C. J.; Huttlinger, N. V.; Oneill, B. A.; Kourtides, D. A.; Parker, J. A.

    1977-01-01

    The toxicity of the pyrolysis gases from nine wood samples was investigated. The samples of hardwoods were aspen poplar, beech, yellow birch, and red oak. The samples of softwoods were western red cedar, Douglas fir, western hemlock, eastern white pine, and southern yellow pine. There was no significant difference between the wood samples under rising temperature conditions, which are intended to simulate a developing fire, or under fixed temperature conditions, which are intended to simulate a fully developed fire. This test method is used to determine whether a material is significantly more toxic than wood under the preflashover conditions of a developing fire.

  20. An optically accessible pyrolysis microreactor

    SciTech Connect

    Baraban, J. H.; Ellison, G. Barney; David, D. E.; Daily, J. W.

    2016-01-15

    We report an optically accessible pyrolysis micro-reactor suitable for in situ laser spectroscopic measurements. A radiative heating design allows for completely unobstructed views of the micro-reactor along two axes. The maximum temperature demonstrated here is only 1300 K (as opposed to 1700 K for the usual SiC micro-reactor) because of the melting point of fused silica, but alternative transparent materials will allow for higher temperatures. Laser induced fluorescence measurements on nitric oxide are presented as a proof of principle for spectroscopic characterization of pyrolysis conditions.

  1. Pyrolysis kinetics of hazelnut husk using thermogravimetric analysis.

    PubMed

    Ceylan, Selim; Topçu, Yıldıray

    2014-03-01

    This study aims at investigating physicochemical properties and pyrolysis kinetics of hazelnut husk, an abundant agricultural waste in Turkey. The physicochemical properties were determined by bomb calorimeter, elemental analysis and FT-IR spectroscopy. Physicochemical analysis results showed that hazelnut husk has a high calorimetric value and high volatile matter content. Pyrolysis experiments were carried out in a thermogravimetric analyzer under inert conditions and operated at different heating rates (5, 10, 20°C/min). Three different kinetic models, the iso-conversional Kissinger-Akahira-Sunose (KAS) and Ozawa-Flynn-Wall (OFW) models and Coats-Redfern method were applied on TGA data of hazelnut husk to calculate the kinetic parameters including activation energy, pre-exponential factor and reaction order. Simulation of hazelnut husk pyrolysis using data obtained from TGA analysis showed good agreement with experimental data. Combining with physicochemical properties, it was concluded that this biomass can become useful source of energy or chemicals.

  2. A Comparative study of microwave-induced pyrolysis of lignocellulosic and algal biomass.

    PubMed

    Wang, Nan; Tahmasebi, Arash; Yu, Jianglong; Xu, Jing; Huang, Feng; Mamaeva, Alisa

    2015-08-01

    Microwave (MW) pyrolysis of algal and lignocellulosic biomass samples were studied using a modified domestic oven. The pyrolysis temperature was recorded continuously by inserting a thermocouple into the samples. Temperatures as high as 1170 and 1015°C were achieved for peanut shell and Chlorella vulgaris. The activation energy for MW pyrolysis was calculated by Coats-Redfern method and the values were 221.96 and 214.27kJ/mol for peanut shell and C. vulgaris, respectively. Bio-oil yields reached to 27.7wt.% and 11.0wt.% during pyrolysis of C. vulgaris and peanut shell, respectively. The bio-oil samples from pyrolysis were analyzed by a gas chromatography-mass spectrometry (GC-MS). Bio-oil from lignocellulosic biomass pyrolysis contained more phenolic compounds while that from microalgae pyrolysis contained more nitrogen-containing species. Fourier transform infrared spectroscopy (FTIR) analysis results showed that concentration of OH, CH, CO, OCH3, and CO functional groups in char samples decreased significantly after pyrolysis.

  3. Uniform-droplet spray forming

    SciTech Connect

    Blue, C.A.; Sikka, V.K.; Chun, Jung-Hoon; Ando, T.

    1997-04-01

    The uniform-droplet process is a new method of liquid-metal atomization that results in single droplets that can be used to produce mono-size powders or sprayed-on to substrates to produce near-net shapes with tailored microstructure. The mono-sized powder-production capability of the uniform-droplet process also has the potential of permitting engineered powder blends to produce components of controlled porosity. Metal and alloy powders are commercially produced by at least three different methods: gas atomization, water atomization, and rotating disk. All three methods produce powders of a broad range in size with a very small yield of fine powders with single-sized droplets that can be used to produce mono-size powders or sprayed-on substrates to produce near-net shapes with tailored microstructures. The economical analysis has shown the process to have the potential of reducing capital cost by 50% and operating cost by 37.5% when applied to powder making. For the spray-forming process, a 25% savings is expected in both the capital and operating costs. The project is jointly carried out at Massachusetts Institute of Technology (MIT), Tuffs University, and Oak Ridge National Laboratory (ORNL). Preliminary interactions with both finished parts and powder producers have shown a strong interest in the uniform-droplet process. Systematic studies are being conducted to optimize the process parameters, understand the solidification of droplets and spray deposits, and develop a uniform-droplet-system (UDS) apparatus appropriate for processing engineering alloys.

  4. Recent progress on biomass co-pyrolysis conversion into high-quality bio-oil.

    PubMed

    Hassan, H; Lim, J K; Hameed, B H

    2016-12-01

    Co-pyrolysis of biomass with abundantly available materials could be an economical method for production of bio-fuels. However, elimination of oxygenated compounds poses a considerable challenge. Catalytic co-pyrolysis is another potential technique for upgrading bio-oils for application as liquid fuels in standard engines. This technique promotes the production of high-quality bio-oil through acid catalyzed reduction of oxygenated compounds and mutagenic polyaromatic hydrocarbons. This work aims to review and summarize research progress on co-pyrolysis and catalytic co-pyrolysis, as well as their benefits on enhancement of bio-oils derived from biomass. This review focuses on the potential of plastic wastes and coal materials as co-feed in co-pyrolysis to produce valuable liquid fuel. This paper also proposes future directions for using this technique to obtain high yields of bio-oils.

  5. Application of a pyroprobe to simulate smoking and metabolic degradation of abused drugs through analytical pyrolysis.

    PubMed

    Gayton-Ely, Melissa; Shakleya, Diaa M; Bell, Suzanne C

    2007-03-01

    Smoking of illicit drugs can produce unique metabolic biomarkers. Smoking conditions can be partially modeled via pyrolysis, a process that decomposes a chemical compound by extreme heat. Pyrolytic decomposition was found to be useful as a limited metabolic mimic in that analytical pyrolysis can be used to generate some of the same compounds produced by metabolic degradation. This project focused on the pyrolysis of cocaine and methamphetamine using a pyroprobe coupled with a GC/MS and more generally, potential applications of pyrolysis to forensic toxicology. Common diluents including lidocaine, caffeine, and benzocaine were pyrolyzed in mixtures with cocaine and methamphetamine. Correlations between pyrolytic and metabolic degradations revealed that this method has the capability to produce some of the reported metabolites such as norcocaine and cocaethylene for cocaine, and amphetamine for methamphetamine. The results demonstrate that analytical pyrolysis has the potential to identify some metabolic products and to supplement in vivo and enzymatic studies.

  6. Structure of high-speed sprays

    NASA Astrophysics Data System (ADS)

    Bracco, Frediano V.

    1995-01-01

    This work covered both measurements and computations and its results are documented in eight appendices. Measurements were made of drop velocity in vaporizing, steady, full-cone sprays and of drop velocity and drop size in non-vaporizing steady full-cone sprays. In similar conditions, measurements had previously been made of the intact core and of the size of the drops in the immediate vicinity of the injector, thus generating an extensive set of data which were particularly useful for the assessment and the development of multidimensional models of engine sprays. On the computational side, a line source technique was introduced to simulate the intact-core in engine sprays and two extensive numerical studies were carried out to explain the strong anisotropy of the drop velocity fluctuations that had been found in the measurements. In another interesting and timely study, the accuracy of the stochastic method of computing drop collisions and coalescence (which is the one universally used) was assessed by corresponding deterministic computations (more accurate but much more time consuming). It was concluded that the accuracy of the stochastic method in practical computations can be wanting. Finally, a numerical study of the structure of hollow-cone sprays was initiated that has since been followed by significant experimental and computational work on liquid-only and air-assisted hollow-cone injectors and sprays.

  7. Large volume water sprays for dispersing warm fogs

    NASA Astrophysics Data System (ADS)

    Keller, V. W.; Anderson, B. J.; Burns, R. A.; Lala, G. G.; Meyer, M. B.

    A new method for dispersing of warm fogs which impede visibility and alter schedules is described. The method uses large volume recycled water sprays to create curtains of falling drops through which the fog is processed by the ambient wind and spray-induced air flow; the fog droplets are removed by coalescence/rainout. The efficiency of this fog droplet removal process depends on the size spectra of the spray drops and optimum spray drop size is calculated as between 0.3-1.0 mm in diameter. Water spray tests were conducted in order to determine the drop size spectra and temperature response of sprays produced by commercially available fire-fighting nozzles, and nozzle array tests were utilized to study air flow patterns and the thermal properties of the overall system. The initial test data reveal that the fog-dispersal procedure is effective.

  8. Sprays and Cartan projective connections

    NASA Astrophysics Data System (ADS)

    Saunders, D. J.

    2004-10-01

    Around 80 years ago, several authors (for instance H. Weyl, T.Y. Thomas, J. Douglas and J.H.C. Whitehead) studied the projective geometry of paths, using the methods of tensor calculus. The principal object of study was a spray, namely a homogeneous second-order differential equation, or more generally a projective equivalence class of sprays. At around the same time, E. Cartan studied the same topic from a different point of view, by imagining a projective space attached to a manifold, or, more generally, attached to a `manifold of elements'; the infinitesimal `glue' may be interpreted in modern language as a Cartan projective connection on a principal bundle. This paper describes the geometrical relationship between these two points of view.

  9. Vacuum Plasma Sprayed Metallic Coatings

    NASA Astrophysics Data System (ADS)

    Shankar, S.; Koenig, D. E.; Dardi, L. E.

    1981-10-01

    Recognizing the fundamental cost advantage, technical capabilities, and compositional flexibility of reduced pressure (vacuum) plasma spraying compared to other overlay coating methods, an advanced, second generation, closed chamber deposition process called VPX (a Howmet trademark) was developed. An automated experimental facility for coating gas turbine engine components was also constructed. This paper describes several important features of the process and equipment. It shows that the use of optimized spray parameters combined with an appropriate schedule of relative orientations between the gun and work-piece can be used to produce dense and highly reproducible coatings of either uniform or controlled thickness distributions. The chemical composition, microstructure, and interfacial characteristics of typical MCrAlY coatings are reported. Some effects of operating procedures and MCrAlY chemical composition on coating density are noted. The results of mechanical property and burner rig tests of coated material are also described.

  10. Corn and sorghum performance are affected by irrigation application method: SDI versus Mid-elevation spray irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It is known that irrigation application method can impact crop water use and water use efficiency, but the mechanisms involved are incompletely understood, particularly in terms of the water and energy balances during the growing season from pre-irrigation through planting, early growth and yield de...

  11. Corn and sorghum performance are affected by irrigation application method: SDI versus mid-elevation spray irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irrigation application method can impact crop water use and water use efficiency (WUE), but the mechanisms involved are incompletely understood, particularly in terms of the water and energy balances during the growing season from pre-irrigation through the planting, early growth and yield developme...

  12. Corn and sorghum performance affected by irrigation application method:SDI versus mid-elevation spray irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It is known that irrigation application method can impact crop water use and water use efficiency, but the mechanisms involved are incompletely understood, particularly in terms of the water and energy balances during the growing season from pre-irrigation through planting, early growth and yield de...

  13. Kinetics of coffee industrial residue pyrolysis using distributed activation energy model and components separation of bio-oil by sequencing temperature-raising pyrolysis.

    PubMed

    Chen, Nanwei; Ren, Jie; Ye, Ziwei; Xu, Qizhi; Liu, Jingyong; Sun, Shuiyu

    2016-12-01

    This study was carried out to investigate the kinetics of coffee industrial residue (CIR) pyrolysis, the effect of pyrolysis factors on yield of bio-oil component and components separation of bio-oil. The kinetics of CIR pyrolysis was analyzed using distributed activation energy model (DAEM), based on the experiments in thermogravimetric analyzer (TGA), and it indicated that the average of activation energy (E) is 187.86kJ·mol(-1). The bio-oils were prepared from CIR pyrolysis in vacuum tube furnace, and its components were determined by gas chromatography/mass spectrometry (GC-MS). Among pyrolysis factors, pyrolysis temperature is the most influential factor on components yield of bio-oil, directly concerned with the volatilization and yield of components (palmitic acid, linoleic acid, oleic acid, octadecanoic acid and caffeine). Furthermore, a new method (sequencing temperature-raising pyrolysis) was put forward and applied to the components separation of bio-oil. Based on experiments, a solution of components separation of bio-oil was come out.

  14. High mass throughput particle generation using multiple nozzle spraying

    DOEpatents

    Pui, David Y.H.; Chen, Da-Ren

    2004-07-20

    Spraying apparatus and methods that employ multiple nozzle structures for producing multiple sprays of particles, e.g., nanoparticles, for various applications, e.g., pharmaceuticals, are provided. For example, an electrospray dispensing device may include a plurality of nozzle structures, wherein each nozzle structure is separated from adjacent nozzle structures by an internozzle distance. Sprays of particles are established from the nozzle structures by creating a nonuniform electrical field between the nozzle structures and an electrode electrically isolated therefrom.

  15. High mass throughput particle generation using multiple nozzle spraying

    DOEpatents

    Pui, David Y. H.; Chen, Da-Ren

    2009-03-03

    Spraying apparatus and methods that employ multiple nozzle structures for producing multiple sprays of particles, e.g., nanoparticles, for various applications, e.g., pharmaceuticals, are provided. For example, an electrospray dispensing device may include a plurality of nozzle structures, wherein each nozzle structure is separated from adjacent nozzle structures by an internozzle distance. Sprays of particles are established from the nozzle structures by creating a nonuniform electrical field between the nozzle structures and an electrode electrically isolated therefrom.

  16. High mass throughput particle generation using multiple nozzle spraying

    DOEpatents

    Pui, David Y. H.; Chen, Da-Ren

    2015-06-09

    Spraying apparatus and methods that employ multiple nozzle structures for producing multiple sprays of particles, e.g., nanoparticles, for various applications, e.g., pharmaceuticals, are provided. For example, an electrospray dispensing device may include a plurality of nozzle structures, wherein each nozzle structure is separated from adjacent nozzle structures by an internozzle distance. Sprays of particles are established from the nozzle structures by creating a nonuniform electrical field between the nozzle structures and an electrode electrically isolated therefrom.

  17. Budesonide Nasal Spray

    MedlinePlus

    ... sneezing, runny, stuffy, or itchy nose caused by hay fever or other allergies (caused by an allergy to ... germs.Budesonide nasal spray controls the symptoms of hay fever or allergies but does not cure these conditions. ...

  18. Fluticasone Nasal Spray

    MedlinePlus

    ... itchy nose and itchy, watery eyes caused by hay fever or other allergies (caused by an allergy to ... germs.Fluticasone nasal spray controls the symptoms of hay fever or allergies but does not cure these conditions. ...

  19. Beclomethasone Nasal Spray

    MedlinePlus

    ... runny, stuffy, or itchy nose (rhinitis) caused by hay fever, other allergies, or vasomotor (nonallergic) rhinitis. It is ... germs.Beclomethasone nasal spray controls the symptoms of hay fever or allergies but does not cure these conditions. ...

  20. Butorphanol Nasal Spray

    MedlinePlus

    ... spray is used to relieve moderate to severe pain. Butorphanol is in a class of medications called ... works by changing the way the body senses pain. ... This branded product is no longer on the market. Generic alternatives may be available.