These are representative sample records from Science.gov related to your search topic.
For comprehensive and current results, perform a real-time search at Science.gov.
1

Method to synthesize and produce thin films by spray pyrolysis  

DOEpatents

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.

Squillante, Michael R. (Waltham, MA)

1982-06-22

2

Method to synthesize and produce thin films by spray pyrolysis  

DOEpatents

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.

Turcotte, Richard L. (Malden, MA)

1982-07-06

3

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

NASA Astrophysics Data System (ADS)

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.

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

2014-10-01

4

Mn doped ZnO nanostructured thin films prepared by ultrasonic spray pyrolysis method  

NASA Astrophysics Data System (ADS)

Mn-doped ZnO thin films with different percentage of Mn content (0, 1, 3 and 5 at.%) and substrate temperature of 350 °C, were deposited by a simple ultrasonic spray pyrolysis method under atmospheric pressure. We have studied the structural and optical properties by using X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR) and ultra-violet visible near infrared (UV-Vis-NIR) spectroscopy. The lattice parameters calculated for the Mn-doped ZnO from XRD pattern were found to be slightly larger than those of the undoped ZnO, which indicate substitution of Mn in ZnO lattice. Compared with the Raman spectra for ZnO pure films, the Mn-doping effect on the spectra is revealed by the presence of additional peak around 524 cm-1 due to Mn incorporation. With increasing Mn doping the optical band gap increases indicating the Burstein-Moss effect.

Baghdad, R.; Kharroubi, B.; Abdiche, A.; Bousmaha, M.; Bezzerrouk, M. A.; Zeinert, A.; El Marssi, M.; Zellama, K.

2012-10-01

5

Spray pyrolysis of CZTS nanoplatelets.  

PubMed

We demonstrate that copper-zinc-tin-sulphide nanoplatelets can be directly grown onto a molybdenum-coated substrate using spray pyrolysis starting from a mixture of metal thiocarbamates precursors. The structure and phase purity of the nanoplatelets is discussed in detail. PMID:25119262

Exarhos, S; Bozhilov, K N; Mangolini, L

2014-10-01

6

The effects of Al doping on the optical constants of ZnO thin films prepared by spray pyrolysis method  

Microsoft Academic Search

Aluminum doped ZnO (AZO) thin films doped with different aluminum concentrations have been prepared by spray pyrolysis method\\u000a onto glass substrates. The optical and structural properties of the films have been investigated by X-ray diffraction and\\u000a optical characterization methods. The X-ray diffraction spectra showed that all of the thin films are of polycrystalline nature.\\u000a The thin films have (002) as

Mujdat Caglar; Saliha Ilican; Yasemin Caglar; Fahrettin Yakuphanoglu

2008-01-01

7

Electrochromic properties of nano-structured nickel oxide thin film prepared by spray pyrolysis method  

Microsoft Academic Search

In this study, we present a simple method to improve the electrochromic properties of a nickel oxide thin film. The method involves a three-step process—(a) conducting indium tin oxide (ITO) nano-particles were first sprayed onto a conducting substrate to form a porous nano-structured ITO layer, (b) nickel oxide film was then deposited onto the nano-structured ITO layer by a spray

Sheng-Hui Lin; Fu-Rong Chen; Ji-Jung Kai

2008-01-01

8

Investigation of the properties of nanostructured Li-doped NiO films using the modified spray pyrolysis method  

NASA Astrophysics Data System (ADS)

The lithium-doped nickel oxide (L-NiO) films were synthetized using the modified spray pyrolysis method with a two-step grown process. By observing the spectra of X-ray photoemission spectroscopy of L-NiO films, the intensity of Ni 2 p 3/2 peak of Ni3+ bonding state increases with increasing Li concentration that causes the decrease of transparency and resistivity. The L-NiO films with optimum characteristics were obtained at Li = 8 at%, where a p-type resistivity of 4.1 × 10-1 ? cm and optical transparency above 76% in the visible region are achieved.

Chia-Ching, Wu; Cheng-Fu, Yang

2013-01-01

9

Doped nanocrystalline ZnO powders for non-linear resistor applications by spray pyrolysis method.  

PubMed

Homogeneous and doped nanocrystalline ZnO powders (30-200 nm) were synthesized by spray pyrolysis technique. The spray pyrolysed powders were calcined in the temperature range of 500-750 degrees C. Formation of insulating pyrochlore phase started from 700 degrees C during the calcination itself. The calcined powders were compacted and sintered at different temperatures ranging from 900-1200 degrees C for 0.5-4 h. The densification behavior was found to be dependent on calcination temperature of the nanopowder. The resulting discs were found to have density (5.34-5.62 g/cc) in the range of 96-99% of theoretical density. The breakdown voltage value obtained for the nanopowder based non-linear resistor is 10.3 kV/cm with low leakage current density of 0.7 microA/cm2 and coefficient of nonlinearity as high as 193. The activation energy for grain growth of the doped ZnO nanopowder powders is 449.4 +/- 15 kJ/mol. PMID:19916460

Hembram, Kaliyan; Vijay, R; Rao, Y S; Rao, T N

2009-07-01

10

Producing Quantum Dots by Spray Pyrolysis  

NASA Technical Reports Server (NTRS)

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.

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

2006-01-01

11

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

Microsoft Academic Search

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

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

2011-01-01

12

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

NASA Astrophysics Data System (ADS)

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.

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

2011-05-01

13

Barium strontium titanate powders prepared by spray pyrolysis  

Microsoft Academic Search

Ultasonic spray pyrolysis (SP) has been investigated for the production of the barium strontium titanate (BST) powders from the polymeric precursors. The processing parameters, such as flux of aerosol and temperature profile inside the furnace, were optimized to obtain single phase BST. The powders were characterized by the methods of X-ray diffraction analysis, SEM, EDS and TEM. The obtained powders

G. Brankovi?; Z. Brankovi?; M. S. Góes; C. O. Paiva-Santos; M. Cilense; J. A. Varela; E. Longo

2005-01-01

14

Mn doping effect on the structural properties of ZnO-nanostructured films deposited by the ultrasonic spray pyrolysis method  

NASA Astrophysics Data System (ADS)

Mn-doped ZnO thin films with different percentages of Mn content (0, 1, 3 and 5 at%) and substrate temperature of 350 °C, were deposited by a simple ultrasonic spray pyrolysis method under atmospheric pressure. The chemical compositions and surface morphologies were examined by dispersive x-ray spectroscopy and scanning electron microscopy micrographs. We have studied the structural and optical properties by using x-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy and ultra-violet visible near-infrared spectroscopy. The lattice parameters calculated for the Mn-doped ZnO from XRD pattern were found to be slightly larger than those of the undoped ZnO, which indicate substitution of Mn in the ZnO lattice. Compared with the Raman spectra for ZnO pure films, the Mn-doping effect on the spectra is revealed by the presence of an additional peak about 524 cm-1 due to Mn incorporation. With increasing Mn doping the optical band gap increases indicating the Burstein-Moss effect.

Kharroubi, B.; Baghdad, R.; Abdiche, A.; Bousmaha, M.; Bousquet, M.; Zeinert, A.; El Marssi, M.; Zellama, K.; Hamzaoui, S.

2012-07-01

15

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

SciTech Connect

The ultrasonic spray pyrolysis (USP) method has been used to prepare submicron hematite (??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.

K?rc?, Burak; Ebin, Burçak; Gürmen, Sebahattin [Department of Metallurgical and Materials Engineering, Istanbul Technical University Istanbul (Turkey)

2013-12-16

16

Effect of nickel doping on physical properties of zinc oxide thin films prepared by the spray pyrolysis method  

NASA Astrophysics Data System (ADS)

In this study, undoped and nickel-doped zinc oxide thin films (ZnO:Ni) were deposited on glass substrates using a spray pyrolysis technique. The effects of the Zn concentration in the initial solution and the substrate temperature on the physical properties of the thin films are studied. The results show that the optimum Zn concentration and substrate temperature for preparation of basic undoped ZnO films with n-type conductivity and high optical transparency are 0.02 M and 350 °C, respectively. Then, by using these optimized deposition parameters, nickel-doped zinc oxide films are prepared. Surface morphology and crystalline structure of the films are investigated by atomic force microscopy (AFM) and X-ray diffractometer. X-ray diffraction (XRD) patterns show that the films are polycrystalline. The structural analysis shows that all the samples have a hexagonal structure. The crystallite size and the preferred orientation were calculated from the XRD data. From AFM investigations, the surface morphology of the nanostructured films is found to depend on the concentration of Ni. Optical measurements have shown that an increase in the Ni doping results in a reduction in the optical transmission of the layer, but it remains higher than 80% for Ni doping greater than 8 wt%. At the same time, the optical gap increases from 3.4 to 4 eV when the Ni ratio increases. The electrical measurements show that the resistance of the films varies with the duration of pulverization and the nickel content of the film. Low values for the electrical resistivity (around 103 ? cm) were obtained for Ni-doped ZnO thin films.

Jlassi, M.; Sta, I.; Hajji, M.; Ezzaouia, H.

2014-05-01

17

Band positions and photoelectrochemical properties of Cu2ZnSnS4 thin films by the ultrasonic spray pyrolysis method  

NASA Astrophysics Data System (ADS)

Cu2ZnSnS4 (CZTS) films were prepared by ultrasonic spray pyrolysis on FTO (SnO2?:?F on glass) substrates. The effect of substrate temperatures on the phases, morphologies and photoelectrochemical properties of CZTS films was investigated. X-ray diffraction, Raman spectrum and energy-dispersive spectrometry were used to confirm the phases of the CZTS films. The samples at 400 and 450 °C exhibited a higher photocurrent than the samples at 350 and 500 °C. Moreover, the band positions of CZTS were measured by a facile Mott-Schottky method for the first time. Different from the previous calculation and experimental data, the conduction band position of CZTS was 0.26 eV higher than that of CdS. The results can explain well the low open circuit voltage of a CZTS-based solar cell and offer guidance to improving CZTS solar cells.

Huang, Sheng; Luo, Wenjun; Zou, Zhigang

2013-06-01

18

Nano-designing of Mg doped phosphate tungsten bronzes and SiO2 composite obtained by ultrasonic spray pyrolysis method.  

PubMed

In this study, the structure and substructure of SiO(2)-Mg phosphate tungsten bronzes, MgPTB, (MgHPW(12)O(40).29H(2)O) obtained by ultrasonic spray pyrolysis method from a silica sol, and a MgPTB solution, obtained by the ion exchange method, as precursors were investigated. The mechanism of the formation of aerosol droplets is discussed. Phase composition, structure and substructure of SiO(2)-MgPTB particles were investigated by X-ray powder diffraction (XRPD) analysis, transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Good agreement between the theoretically predicted values for the mean diameters of particles and subparticles (1.27 microm and 75.4 nm, respectively) and the experimentally obtained ones (1.17 microm and 65-90 nm) was found. This agreement confirms the applicability of the model to get a satisfactory prediction of the most important data related to the nano-structural design of SiO(2)-MgPTB powders. PMID:19501536

Jokanovic, V; Nedic, Z

2010-01-01

19

Ultrafine titania by flame spray pyrolysis of a titanatrane complex  

Microsoft Academic Search

Ultrafine titania particles can be produced by flame spray pyrolysis of a chelated metal alkoxide. The precursor can be made by reacting a titanium hydrosol with triethanolamine in ethylene glycol. The chelate, dissolved in ethanol, is misted as an aerosol into an oxidizing flame where it undergoes combustion. The combustion process generates particles, probably by a gas phase condensation process,

Clint R. Bickmore; Kurt F. Waldner; Rita Baranwal; Tom Hinklin; David R. Treadwell; Richard M. Laine

1998-01-01

20

Effect of aluminium doping on zinc oxide thin films grown by spray pyrolysis  

Microsoft Academic Search

We report the structural, optical, and electrical characterization of aluminium-doped zinc oxide thin films grown by the spray pyrolysis method. We report the effect of Al concentration on the resistivity and on the X-ray diffraction, transmittance, photoluminescence and Raman scattering spectra of the films. The minimum resistivity is obtained for the sample with nominal Al concentration of 1%. An increase

A. El Manouni; F. J. Manjón; M. Mollar; B. Marí; R. Gómez; M. C. López; J. R. Ramos-Barrado

2006-01-01

21

Controlled synthesis of nanostructured particles by flame spray pyrolysis  

Microsoft Academic Search

The flame spray pyrolysis (FSP) process was systematically investigated using an external-mixing gas-assisted atomizer supported by six premixed methane–oxygen flameletes. The effect of oxidant and precursor fuel composition on the size of FSP-made silica primary particles (8–40nm) was studied using as precursor hexamethyldisiloxane (HMDSO) dissolved in ethanol, iso-octane or methanol. As oxidant air and pure oxygen were used, that served

L. Mädler; H. K. Kammler; R. Mueller; S. E. Pratsinis

2002-01-01

22

Porous Carbon Powders Prepared by Ultrasonic Spray Pyrolysis Sara E. Skrabalak and Kenneth S. Suslick*  

E-print Network

Porous Carbon Powders Prepared by Ultrasonic Spray Pyrolysis Sara E. Skrabalak and Kenneth S Until recently, most porous carbons were prepared by carbonization of raw natural materials2 (e.g., wood to the destruction of (relatively) expensive templates. Here, we use ultrasonic spray pyrolysis (USP)6

Suslick, Kenneth S.

23

ZnO layers prepared by spray pyrolysis  

NASA Astrophysics Data System (ADS)

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.

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

1998-02-01

24

Effect of doping level and spray time on zinc oxide thin films produced by spray pyrolysis for transparent electrodes applications  

Microsoft Academic Search

In this paper, we present the results of optical, electrical and structural properties of zinc oxide (ZnO) semiconductors thin layers with various aluminium (Al) doping level and deposited at different spray time using the spray pyrolysis technique in atmospheric pressure. The study of optical properties from reflection and transmission spectra shows a high transmission value a band gap energy of

Z. Ben Achour; T. Ktari; B. Ouertani; O. Touayar; B. Bessais; J. Ben Brahim

2007-01-01

25

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

SciTech Connect

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.

Fotou, G.P.; Himebaugh, L.; Kodas, T.T. [Univ. of New Mexico, Albuquerque, NM (United States); Wu, M. [Kemira Pigments, Inc., Savannah, GA (United States)

1996-12-31

26

Aqueous synthesis of interconnected ZnO nanowires using spray pyrolysis deposited seed layers  

Microsoft Academic Search

Interconnected ZnO nanowires were grown in a two-stage process, using spray pyrolysis deposited ZnO seed layers as a nucleation platform for subsequent hydrothermal growth. We present a comparison between the effect of these spray pyrolysis deposited seed layers and well-ordered sputter deposited seed layers, along with their respective ZnO nano-morphologies that were obtained via hydrothermal growth. It will be shown

Michael Breedon; Mohammad Bagher Rahmani; Sayyed-Hossein Keshmiri; Wojtek Wlodarski; Kourosh Kalantar-zadeh

2010-01-01

27

Nano-sized manganese oxide particles prepared by low-pressure spray pyrolysis using FEAG process  

Microsoft Academic Search

Nano-sized manganese oxide particles were prepared by low-pressure spray pyrolysis using the new type of liquid aerosol generator called as FEAG process. The particles prepared from polymeric precursors spray solution with organic additives had large size, hollow and fractured morphologies due to the gas evolution from the decomposition of the organic additives. The precursor particles with micron size, hollow and

Seo Hee Ju; Yun Chan Kang

2008-01-01

28

Methods and apparatuses for preparing upgraded pyrolysis oil  

DOEpatents

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.

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

2013-10-01

29

Synthesis of carbon encapsulated magnetic nanoparticles with giant coercivity by a spray pyrolysis approach.  

PubMed

Carbon encapsulated magnetic (metal) nanoparticles (CEMNPs) have wide applications in biomedicine and the magnetic recording industry. However, synthesis of such particles with a high coercive force and good ferromagnetism is still a great challenge. The present study reports a new method for the continuous production of CEMNPs of high purity. This involves the spray pyrolysis of a mixture of iron pentacarbonyl and ethanol at 500-900 degrees C. Results show that the Fe (or Fe3C) particles synthesized at 700 and 900 degrees C were well encapsulated by graphitic layers with rare byproducts such as carbon nanotubes, nanofibers, or bulk amorphous carbon. Those synthesized at 700 degrees C had a particle size of 30-50 nm, a giant coercive force of 867 Oe, and a good magnetic remanence of 33% at room temperature. The present approach based on spray pyrolysis is advantageous over previous ones in suitability for large-scale production, and the synthesized material has wide applications in many fields. PMID:17269820

Wang, Jian Nong; Zhang, Li; Yu, Fan; Sheng, Zhao Ming

2007-03-01

30

Electrical and optical properties of fluorine-doped ZnO thin films prepared by spray pyrolysis  

Microsoft Academic Search

Undoped and fluorine-doped ZnO thin films deposited by spray pyrolysis onto soda-lime glass substrates were electrically and optically characterized. Resistivities as low as 1×10?1 ? cm, Hall mobility as high as 10 cm2\\/V per s and effective carrier concentration as high as 4×1019 cm?3 have been obtained. Relative fluorine concentration was determined by the resonant nuclear reaction method. Electron concentrations

A. Sanchez-Juarez; A Tiburcio-Silver; A Ortiz; E. P Zironi; J Rickards

1998-01-01

31

The characteristics of nano-sized manganese oxide particles prepared by spray pyrolysis  

Microsoft Academic Search

Nano-sized Mn2O3 particles with regular morphologies were prepared using spray pyrolysis. The spherical, micron-sized precursor particles obtained from a spray solution with citric acid and ethylene glycol turned into nano-sized Mn2O3 particles after post-treatment. The particles prepared from a carrier gas with a high flow rate had fine sizes and regular morphologies after post-treatment. The mean sizes of the Mn2O3

Seo Hee Ju; Do Youp Kim; Hye Young Koo; Seung Kwon Hong; Eun Byul Jo; Yun Chan Kang

2006-01-01

32

Influence of the doping and annealing atmosphere on zinc oxide thin films deposited by spray pyrolysis  

Microsoft Academic Search

Undoped and doped (indium and aluminium) zinc oxide (ZnO) thin films have been prepared by spray pyrolysis, and the effect of the doping and annealing atmosphere on the electrical, optical and structural properties of the produced films has been investigated. The deposited films have a high resistivity. Annealing the films in an argon atmosphere or under vacuum leads to a

P Nunes; A Malik; B Fernandes; E Fortunato; P Vilarinho; R Martins

1999-01-01

33

Flame spray pyrolysis based nano-structured functional metal oxide layers for gas sensing applications  

Microsoft Academic Search

The contribution presents the results obtained in the last years by applying an established aerosol based production technology for metal oxide nanoparticles mainly used in catalysis and filler materials, the so called flame spray pyrolysis (FSP), to gas sensor fabrication. The final achievement of this technology is a fast and clean single step process to fabricate fully functionalized multilayer sensors.

Nicolae Barsan; Lutz Mädler; Udo Weimar

2007-01-01

34

Synthesis and characterization of nanostructured nickel oxide thin films prepared with chemical spray pyrolysis  

Microsoft Academic Search

Nickel oxide thin films have been deposited in an open atmosphere onto glass substrates by chemical spray pyrolysis using aqueous nickel acetate solutions and air as driving gas. The films show a strong variation in the surface morphology depending on the substrate temperature and the precursor solution flux. At 350°C substrate temperature, a reticular tissue-like film morphology is obtained, becoming

R. Romero; F. Martin; J. R. Ramos-Barrado; D. Leinen

2010-01-01

35

Growth of vertically aligned carbon nanotubes on silicon and quartz substrate by spray pyrolysis of a natural precursor: Turpentine oil  

NASA Astrophysics Data System (ADS)

Vertically aligned carbon nanotubes (VACNTs) were grown by spray pyrolysis of turpentine oil and ferrocene mixture at 700 °C. Using this simple method, we report the successful growth of vertically aligned nanotubes of 300 ?m length and diameter in the range of 50-100 nm on Si(1 0 0) substrate. The ferrocene act as an in situ Fe catalyst precursor and forming the nanosize iron particles for formation of VACNTs on Si and quartz substrates. Morphological differences between aligned carbon nanotubes grown on different substrates are studied and discussed by SEM, TEM and Raman spectroscopy characterizations.

Afre, Rakesh A.; Soga, T.; Jimbo, T.; Kumar, Mukul; Ando, Y.; Sharon, M.

2005-10-01

36

Gas sensing properties of WO3-doped ZnO nanoparticles synthesized by flame spray pyrolysis  

Microsoft Academic Search

The flame-made (5\\/5) pure ZnO and WO3-doped ZnO nanoparticles containing 0.25, 0.50, and 0.75 mol% of WO3 were successfully synthesized by flame spray pyrolysis (FSP). These materials were studied for NO2, CO and H2 gas sensing at different gas concentrations and operating temperatures ranging from 300-400°C in dry air. The crystalline phase, morphology and size of the nanoparticles were characterized

C. Siriwong; K. Wetchakun; A. Wisitsoraat; S. Phanichphant

2009-01-01

37

Preparation of lithium manganese oxide fine particles by spray pyrolysis and their electrochemical properties  

Microsoft Academic Search

Highly crystalline nano-sized lithium manganese oxide particles were fabricated by spray pyrolysis. The resultant particles had well-developed facet planes in a transmission electron microscopy (TEM) image and electron diffraction pattern from a single particle also showed clear diffraction spots, indicating that the prepared particles were highly crystalline. The mean crystallite size estimated from X-ray diffraction peaks was ca. 18nm, which

Y. Iriyama; Y. Tachibana; R. Sasasoka; N. Kuwata; T. Abe; M. Inaba; A. Tasaka; K. Kikuchi; J. Kawamura; Z. Ogumi

2007-01-01

38

Preparation of ZnO-doped Al films by spray pyrolysis technique  

Microsoft Academic Search

Al-doped zinc oxide (AZO) thin films have been prepared by spray pyrolysis (SP) technique of zinc acetate and aluminium nitrate, and the effect of thickness on structural and optical properties has been investigated. The structural and optical characteristics of the AZO films were examined by X-ray diffraction (XRD) and double-beam spectrophotometry. These films, deposited on glass substrates at an optimal

M. A. Kaid; A. Ashour

2007-01-01

39

Ultrafine spinel powders by flame spray pyrolysis of a magnesium aluminum double alkoxide  

Microsoft Academic Search

Ultrafine crystalline spinel powder has been prepared using flame spray pyrolysis of alcoholic solutions of a novel double alkoxide precursor. The particles produced are spherical, dense, single crystals with diameters of 10--100 nm and specific surface areas ranging from 40 to 60 m²\\/g. Powder production rates of 50--100 g\\/h are achieved using a bench-top apparatus. Particle formation appears to occur

Clint R. Bickmore; Kurt F. Waldner; David R. Treadwell; Richard M. Laine

1996-01-01

40

Studies on electrochromic properties of nickel oxide thin films prepared by spray pyrolysis technique  

Microsoft Academic Search

Electrochromic nickel oxide thin films were prepared by using a simple and inexpensive spray pyrolysis technique (SPT) onto fluorine-doped tin oxide (FTO) coated glass substrates from nickel chloride solution. Transparent NiO-thin films were obtained at a substrate temperature 350°C. The films were cubic NiO with preferred orientation in the (111) direction. Infrared spectroscopy results show presence of free hydroxyl ion

L. D. Kadam; P. S. Patil

2001-01-01

41

Emission of ZnO:Ag nanorods obtained by ultrasonic spray pyrolysis  

NASA Astrophysics Data System (ADS)

Scanning electronic microscopy (SEM), X ray diffraction (XRD), photoluminescence (PL) and its temperature dependence have been studied in ZnO:Ag nanorods (NRs) prepared by the ultrasonic spray pyrolysis (USP) method. The time variation at the growth of ZnO:Ag films permits modifying the ZnO phase from the amorphous to crystalline, to change the size of ZnO:Ag NRs and to vary their emission spectra. PL spectra of ZnO:Ag NRs versus temperature has been investigated. This study reveals that the PL band related to the acceptor AgZn (LO phonon replicas of an acceptor bound exciton, ABE (2.877 eV)), and its second-order diffraction peak (1.44 eV) disappeared in the temperature range of 10-170 K with the formation of free exciton (FX). The PL intensity of defect related PL bands decreases monotonously in the range 10-300 K with the activation energy of 13 meV. The PL band (3.22 eV), related to the LO phonon replica of free exciton (FX-2LO) and its second-order diffraction peak (1.61 eV) increase monotonously in the range 10-300 K. FX related peak dominates in PL spectra at room temperature that testifies on the high quality of ZnO:Ag films prepared by the USP technology.

Velázquez Lozada, E.; Torchynska, T. V.; Casas Espinola, J. L.; Pérez Millan, B.

2014-11-01

42

Ultrasonic spray pyrolysis of nano crystalline spinel LiMn 2O 4 showing good cycling performance in the 3 V range  

Microsoft Academic Search

Spherical lithium manganese oxide spinel was synthesized by an ultrasonic spray pyrolysis method, and has been characterized using X-ray diffraction, scanning electron microscopy, transimission electron microscopy and electrochemical cycling at 3V regions. The LiMn2O4 powders were composed of about 10nm-sized primary particles. The delivered discharge capacity of the synthesized nano-material was 125mAhg?1 between 2.4 and 3.5V and its retention was

Sang-Ho Park; Seung-Taek Myung; Sung-Woo Oh; Chong Seung Yoon; Yang-Kook Sun

2006-01-01

43

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

NASA Technical Reports Server (NTRS)

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.

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

2002-01-01

44

Zinc Oxide Thin-Film Transistors Fabricated at Low Temperature by Chemical Spray Pyrolysis  

NASA Astrophysics Data System (ADS)

We report the electrical behavior of undoped zinc oxide thin-film transistors (TFTs) fabricated by low-temperature chemical spray pyrolysis. An aerosol system utilizing aerodynamic focusing was used to deposit the ZnO. Polycrystalline films were subsequently formed by annealing at the relatively low temperature of 140°C. The saturation mobility of the TFTs was 2 cm2/Vs, which is the highest reported for undoped ZnO TFTs manufactured below 150°C. The devices also had an on/off ratio of 104 and a threshold voltage of -3.5 V. These values were found to depend reversibly on measurement conditions.

Jeong, Yesul; Pearson, Christopher; Lee, Yong Uk; Winchester, Lee; Hwang, Jaeeun; Kim, Hongdoo; Do, Lee-Mi; Petty, Michael C.

2014-11-01

45

Fabrication of dye-sensitized solar cells by spray pyrolysis deposition (SPD) technique  

Microsoft Academic Search

Porous TiO2 films were successfully synthesized in air from a commercial TiO2-sol by spray pyrolysis deposition (SPD) technique. The film consisted of fine TiO2 particles, approximately 30–50nm in size, and showed the roughness factor as high as 1000. A dye-sensitized solar cell was constructed by SPD technique. In this technique, porous TiO2\\/dense TiO2\\/SnO2:F junction was prepared within 10–15min, which drastically

Masayuki Okuya; Koji Nakade; Daisuke Osa; Takafumi Nakano; G. R Asoka Kumara; Shoji Kaneko

2004-01-01

46

Ultrafine spinel powders by flame spray pyrolysis of a magnesium aluminum double alkoxide  

SciTech Connect

Ultrafine crystalline spinel powder has been prepared using flame spray pyrolysis of alcoholic solutions of a novel double alkoxide precursor. The particles produced are spherical, dense, single crystals with diameters of 10--100 nm and specific surface areas ranging from 40 to 60 m{sup 2}/g. Powder production rates of 50--100 g/h are achieved using a bench-top apparatus. Particle formation appears to occur by rapid oxidation of the organic ligands followed by nucleation and growth from oxide species.

Bickmore, C.R.; Waldner, K.F.; Treadwell, D.R.; Laine, R.M. [Univ. of Michigan, Ann Arbor, MI (United States)

1996-05-01

47

Transparent conducting lithium-doped nickel oxide thin films by spray pyrolysis technique  

Microsoft Academic Search

Nickel oxide (NiO) and lithium-doped nickel oxide films were deposited by the spray pyrolysis technique using NiCl2 and LiCl\\u000a as starting materials. All the films were greenish-grey in colour and confirmed by X-ray analysis. The best NiO films were\\u000a obtained when the substrate temperature, Ts=480 C where a conductivity of 2.110-1?-1 cm-1 and transparency above 80% in\\u000a the visible region

P Puspharajah; S Radhakrishna; A. K Arof

1997-01-01

48

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

NASA Astrophysics Data System (ADS)

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.

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

2006-09-01

49

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

PubMed

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. PMID:23408113

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

2011-07-01

50

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

PubMed Central

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

Rudin, Thomas; Wegner, Karsten

2013-01-01

51

Characteristics of spherical-shaped Li 4Ti 5O 12 anode powders prepared by spray pyrolysis  

Microsoft Academic Search

Spherical-shaped Li4Ti5O12 anode powders with a mean size of 1.5?m were prepared by spray pyrolysis. The precursor powders obtained by spray pyrolysis had no peaks of crystal structure of Li4Ti5O12. The powders post-treated at temperatures of 800 and 900°C had the single phase of spinel Li4Ti5O12. The powders post-treated at a temperature of 1000°C had main peaks of the Li4Ti5O12

Seo Hee Ju; Yun Chan Kang

2009-01-01

52

Characterisation of samarium and nitrogen co-doped TiO2 films prepared by chemical spray pyrolysis  

NASA Astrophysics Data System (ADS)

The sol-gel chemical spray pyrolysis method was used to deposit samarium and nitrogen co-doped TiO2 films onto a quartz substrate at a growth temperature of 450 °C using pulsed spray solution feed, followed by annealing at 500 °C for 2 h in air. The obtained films exhibited anatase structure independent of the doping level. According to XRD analysis, the mean crystallite size of the undoped TiO2, TiO2:N(25) and TiO2:N(5):Sm(5) films was 32, 38 and 20 nm, respectively. According to AFM, the undoped TiO2 film consisted of agglomerates with a size of 30-200 nm. N-doping (25 at%) transformed the agglomerates into individually distinctive grains with a size of ca. 30 nm, while Sm doping (5 at%) caused a significant decrease in the average diameter of the agglomerates to ca. 100 nm. The RMS roughness of the undoped TiO2 film was 1.7 nm; doping resulted in the formation of smoother films with RMS roughness of 0.9-1.4 nm. XPS data indicated that the Sm and N dopants were incorporated into the TiO2 crystal lattice and/or adsorbed on the surface of the film. An increasing nitrogen concentration in the spray solution correlates to a systematic suppressing of the photoluminescence intensity of Sm3+.

Oja Acik, I.; Kiisk, V.; Krunks, M.; Sildos, I.; Junolainen, A.; Danilson, M.; Mere, A.; Mikli, V.

2012-11-01

53

Electrochemical properties of tungsten sulfide-carbon composite microspheres prepared by spray pyrolysis  

NASA Astrophysics Data System (ADS)

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%.

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

2014-08-01

54

Electrochemical properties of tungsten sulfide-carbon composite microspheres prepared by spray pyrolysis  

PubMed Central

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

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

2014-01-01

55

Surfactant-assisted ultrasonic spray pyrolysis of nickel oxide and lithium-doped nickel oxide thin films, toward electrochromic applications  

NASA Astrophysics Data System (ADS)

Lithium-doped nickel oxide and undoped nickel oxide thin films have been deposited on FTO/glass substrates by a surfactant-assisted ultrasonic spray pyrolysis. The addition of polyethylene glycol in the sprayed solution has led to improved uniformity and reduced light scattering compared to films made without surfactant. Furthermore, the presence of lithium ions in NiO films has resulted in improved electrochromic performances (coloration contrast and efficiency), but with a slight decrease of the electrochromic switching kinetics.

Denayer, Jessica; Bister, Geoffroy; Simonis, Priscilla; Colson, Pierre; Maho, Anthony; Aubry, Philippe; Vertruyen, Bénédicte; Henrist, Catherine; Lardot, Véronique; Cambier, Francis; Cloots, Rudi

2014-12-01

56

Growth of ZnO and ZnMgO nanorods on Si substrates by using ultrasonic spray pyrolysis  

NASA Astrophysics Data System (ADS)

We demonstrate the growth of ZnO and ZnMgO nanorods on Si substrates through a two-step process without a catalyst by using a simple ultrasonic spray pyrolysis method. First, a ZnO thin film was deposited on a Si substrate to make a seed layer; then, ZnO and ZnMgO nanorods were deposited on that seed layer. ZnO and ZnMgO nanorods with a p-n junction were obtained by using nitrogen doping for p-type nanorods, and gallium doping for n-type nanorods. A distinct electroluminescence was observed at room temperature from the ZnO and the ZnMgO nanorod structures under forward bias conditions.

Nguyen, Hai Dong; Pandey, Rina; Yuldashev, Shavkat; Lee, Dong Jin; Kang, Tae Won

2012-05-01

57

Structural, optical and electrical properties of transparent conducting hydrophobic cadmium oxide thin films prepared by spray pyrolysis technique  

NASA Astrophysics Data System (ADS)

Cadmium oxide thin films were deposited by spray pyrolysis method on the glass substrate at 300 °C using different concentration of cadmium acetate. X-ray diffraction (XRD) measurements show that the coated CdO film belongs to cubic crystal structure with preferential orientation along (1 1 1) direction. Wettability results revealed that the hydrophobic character of CdO thin film is enhanced with increase in the precursor concentrations. The surface morphology and roughness of the films were determined by Atomic Force Microscope (AFM). The average optical transmittance of CdO films in the range 400-800 nm, is about 80%. The resistivity, mobility and carrier concentration of CdO thin films were determined by Hall effect measurement. Photoluminescence (PL) spectra showed a strong emission peak around 590 nm.

Sankarasubramanian, K.; Soundarrajan, P.; Sethuraman, K.; Ramesh Babu, R.; Ramamurthi, K.

2014-05-01

58

Effect of aluminium doping on structural and gas sensing properties of zinc oxide thin films deposited by spray pyrolysis  

Microsoft Academic Search

A facile spray pyrolysis route is used to deposit aluminium doped ZnO (AZO) thin films on to the glass substrates. It is observed that on aluminium doping the particle size of ZnO reduces significantly; moreover, uniformity of particle also gets enhanced. Their XRD study reveals that intensity ratio of crystal planes depend on the aluminium doping concentration. The gas response

Satish S. Badadhe; I. S. Mulla

2011-01-01

59

Synthesis and characterization of nickel oxide thin films deposited on glass substrates using spray pyrolysis  

NASA Astrophysics Data System (ADS)

A simple and inexpensive spray pyrolysis technique was employed to deposit nickel oxide (NiO) thin films from hydrated nickel chloride salt solution onto amorphous glass substrate. The as-deposited films were transparent, uniform and well adherent to the glass substrate. The effect of the substrate temperature, the volume and the concentration of the sprayed solution on the structural, optical and electrical properties was studied using X-ray diffraction, optical transmittance, four point probe, scanning electron microscopy and atomic force microscopy. The structural analyses show that all the samples have a cubic structure. It was found that the increase in the volume of sprayed solution leads to an increment in the crystallite size of NiO and improves the homogeneity of the film. Optical measurements have shown that an increase in the thickness of the layer results in a decrease in the optical transmission, but it remains higher than 70% even if the thickness exceeds 600 nm. At the same time, the optical gap decreases from 3.7 to 3.55 eV when the thickness increases from 133 to 620 nm. Low values of the electrical resistivity (less than 10 ? cm) were obtained for thin films with thicknesses less than about 240 nm, but for higher thicknesses the resistivity increases linearly to reach about 170 ? cm for a thickness of 620 nm.

Jlassi, M.; Sta, I.; Hajji, M.; Ezzaouia, H.

2014-07-01

60

Position-selective growth of ZnO nanowires by ultrasonic spray pyrolysis  

NASA Astrophysics Data System (ADS)

Position-selective growth of ZnO nanowires was realized by utilizing a patterned soda-lime glass layer. The soda-lime glass layer contributes as the origin of nucleation sites for the growth of nanowires in economically viable ultrasonic spray pyrolysis technique. The formation of nanowires took place with good reproducibility at relatively low substrate temperatures of 250- 400C when the soda-lime glass matrix was present at the surface of substrates, and such a nitrate compound as nitric acid or nitrate salt was mixed in the precursor solutions. Based on this technique, the position-selective growth and density-controlled growth of ZnO nanowires can be performed on various types of substrate. The presence of a CaO compound in the glass matrix was revealed as an important condition to grow the nanowires.

Than Htay, Myo; Hashimoto, Yoshio; Momose, Noritaka; Ito, Kentaro

2009-10-01

61

Optoelectronic characteristics of YAG phosphor-incorporated ZnO films deposited by ultrasonic spray pyrolysis  

PubMed Central

This work presents a novel white light device. An yttrium aluminum garnet (YAG) phosphor-incorporated zinc oxide (ZnO) film is deposited on a slide glass substrate by ultrasonic spray pyrolysis. A nanoflower consisting of a hexagonal nanopetal is formed on the surfaces of the samples, and the sizes of the nanopetal are approximately 200 to 700 nm. Additionally, the nanopetal becomes blunted with an increasing incorporated amount of YAG. As the incorporated amount is 1.5 and 2.5 wt.%, the photoluminescence color of the YAG-incorporated ZnO film is nearly white, possibly contributing to the YAG emission and the band-to-deep level transition in the ZnO film. PMID:23151219

2012-01-01

62

Carbon Nanotubes Using Palm Oil as Carbon Source in Spray Pyrolysis System  

NASA Astrophysics Data System (ADS)

Carbon nanotubes (CNTs) have been synthesized by catalytic decomposition of palm oil, on a silica powder support impregnated with Co, Ni and Co/Ni catalysts in the temperature range 500-900° C by the Spray Pyrolysis System. Co/Ni catalyst with 5 wt.% (molar ratio of Co:Ni = 1:1), impregnated in silica was found most suitable. Field Emission Scanning Electron Microscope (FESEM) reveals that the CNTs diameter ranging from 33-53 nm depending upon the conditions of deposition. The morphological studies support `tip growth mechanism' and `base growth mechanism' depending on the size of catalyst for the growth of the CNT's. FTIR results also presented in the paper.

Azira, A. A.; Zainal, N. F. A.; Nik, S. F.; Rusop, M.

2009-06-01

63

Flame temperature trends in reacting vanadium and tungsten ethoxide fluid sprays during CO2-laser pyrolysis  

NASA Astrophysics Data System (ADS)

We observe the "invisible-to-the-naked-eye" flames of tungsten and vanadium ethoxide aerosols when ignited at moderate laser excitation (0< P laser<70 W) by employing an IR thermo-graphic camera. No emission is seen in the visible range whether by the visible region cameras or by spectroscopy. The emissivity of the precursor solution measured was 0.80 and 0.75 for tungsten and vanadium ethoxide, respectively. The spectral emissivities of the tungsten and vanadium ethoxide flames measured using FTIR-spectrometer were used to calculate the pyrolysis flame temperature at various laser intensities and wavelengths. New energy balance equations have been derived—the transient temperature one extended from Haggerty-Cannon equation and the other based on standard resonance analysis. Fitting these models to experimental data reveals that only small amounts (1.33% and 4.32%, respectively) of the laser power are used in the pyrolysis of the precursor ethoxide aerosols into the desired oxide nanostructures. The low levels of specific heat capacity values obtained in these sprays suggest that these are electronic heat capacities rather than lattice heat capacities; enthalpies are also obtained. The experimental temperature-laser power trends observed were in agreement with previous findings from Tenegal et al. (Chem. Phys. Lett. 335:155, 2001). The damping coefficients, and hence the saturation intensities confirm that the vanadium containing precursor liquid is harder to dissociate into final products than the tungsten precursor as observed experimentally.

Mwakikunga, B. W.; Mudau, A. E.; Brink, N.; Willers, C. J.

2011-11-01

64

Third order non linear optical properties of ZnO:Al thin films prepared by spray pyrolysis  

Microsoft Academic Search

In this study, zinc oxide (ZnO) and aluminium doped zinc oxide (ZnO:Al) thin films were deposited by reactive chemical pulverization spray pyrolysis technique on heated glass substrates at 450degC. X-ray diffraction (XRD), scanning electron microscopy (SEM) and third harmonic generation (THG) are used to characterize their structure , morphology and nonlinear optical properties as a function of Al concentration (0,

K. Bahedi; M. Addou; M. El Jouad; Z. Sofiani; S. Bayoud; M. Bouaouda; B. Sahraoui; Z. Essaidi

2009-01-01

65

Fabrication and characterization of fluorine-doped thin oxide thin films and nanorod arrays via spray pyrolysis  

Microsoft Academic Search

This paper reports the synthesis and characterization of fluorine-doped tin oxide (FTO) thin films via intermittent spray\\u000a pyrolysis utilizing a solution mixture of tin chloride pentahydrate and ammonia fluoride. Utilizing the same solution, nanorod\\u000a arrays were fabricated via template-based growth. Uniform and crack-free FTO films over 20×20 mm with a thickness up to 900 nm\\u000a have been routinely achieved; such FTO films

B. Russo; G. Z. Cao

2008-01-01

66

Structural evolution and optical characterization of indium doped cadmium sulfide thin films obtained by spray pyrolysis for different substrate temperatures  

Microsoft Academic Search

Indium doped cadmium sulfide thin films were prepared by spray pyrolysis on glass substrates at different temperatures ranging from 300°C to 450°C in 25°C steps, using aqueous solution of copper chloride and thiourea salts. We used In(COOH)3 as the dopant. Structural characterization was carried out by X-ray diffractometry and scanning electron microscopy and high resolution electron microscopy were used together

Dwight R. Acosta; Carlos R. Magaña; Arturo I. Mart??nez; Arturo Maldonado

2004-01-01

67

Effect of Urea, NH 4OH, and DCCA on Texture Properties of Alumina Prepared by Ultrasonic Spray Pyrolysis  

Microsoft Academic Search

Mesoporous alumina particles were prepared by using a spray pyrolysis process of aluminum nitrate precursor using cetyltrimethylammonium bromide (CTAB) as a structure-directing agent. The effects of ammonium hydroxide, urea, and drying-control-chemical agent (DCCA) on the particle morphology and pore properties of alumina particles were studied by means of N2 physical adsorption, transmission electron microscopy (TEM), and small-angle X-ray diffraction (SAXS)

Joo Hyun Kim; Kyeong Youl Jung; Kyun Young Park

68

Comparative study of nano-structured CdS thin films prepared by CBD and spray pyrolysis: Annealing effect  

Microsoft Academic Search

CdS films were deposited on glass and ITO-covered glass substrates by two techniques: chemical bath deposition (CBD) and spray pyrolysis technique. CdCl2 and thiocarbamide were used as basic precursors in both cases.After deposition, films were isothermally annealed in evacuated (1.3 Pa) quartz ampoules at 450 °C for 5 min and slowly cooled down to room temperature.The morphology of the films

J. Hiie; T. Dedova; V. Valdna; K. Muska

2006-01-01

69

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

NASA Astrophysics Data System (ADS)

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 ?.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 ?.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.%.

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

1999-02-01

70

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

PubMed

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. PMID:25007002

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

71

Synthesis and characterization of Mo doped SnO2 thin films with spray pyrolysis  

NASA Astrophysics Data System (ADS)

Tin oxide thin films doped with different Mo content were successfully grown by spray pyrolysis and they were characterized as a function of Mo content, changed from 0 to 3.5 at.% with 0.5 at.% step. The XRD studies showed that the films had SnO2 cassiterite structure with (2 1 1) preferential orientation and the best crystal properties was observed for 2 at.% Mo doped sample. The SEM images indicated the films were made up of nanosized grains and it was observed pyramidal, polyhedron shaped grains on the deposited films' surfaces. From electrical and optical studies, although 2 at.% Mo doped SnO2 film exhibited the lowest sheet resistance (39.81 ?) and the highest IR reflective (81.77%), 1 at.% Mo doped film has the highest optical band gap (4.011 eV). The lowest Urbach energy (293 meV) and the highest figure of merit (1.80 × 10-3 ?-1) values were observed for 0.5 at.% Mo doped sample between all films. The results found in present study showed that Mo doped SnO2 thin films is a good candidate for solar cells, IR coating and other optoelectronic and technological applications.

Turgut, Güven; Sönmez, Erdal

2014-05-01

72

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

NASA Astrophysics Data System (ADS)

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-?m-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.

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

2014-01-01

73

Synthesis of electrochromic vanadium oxide by pulsed spray pyrolysis technique and its properties  

NASA Astrophysics Data System (ADS)

A new improved pulsed spray pyrolysis technique (PSPT) was employed to deposit a vanadium oxide (V2O5) thin film from a methanolic vanadium chloride precursor onto glass and conducting F : SnO2 coated glass substrates. The structural, morphological, electrical, optical and spectroscopic properties of the film deposited at 573 K were studied. Infrared spectroscopy and x-ray diffraction confirmed the presence of the V2O5 phase. The V2O5 film (thickness ~118 nm) is polycrystalline with a tetragonal crystal structure. Scanning electron microscopy reveals compact granular morphology consisting of ~80-100 nm size grains. The film is transparent in the visible region (average %T ~70%) with an optical band gap energy of 2.47 eV involving both direct and indirect optical transitions. The room temperature electrical resistivity (conductivity) of the film is 1.6 × 108 ? cm (6.25 × 10-9 S cm-1) with an activation energy of 0.67 eV in the temperature range 300-550 K. It exhibited cathodic electrochromism in the lithium containing electrolyte (0.5 M LiClO4 + propylene carbonate).

Patil, C. E.; Tarwal, N. L.; Shinde, P. S.; Deshmukh, H. P.; Patil, P. S.

2009-01-01

74

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

NASA Astrophysics Data System (ADS)

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.

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

2011-09-01

75

Superhydrophobic and transparent ZnO thin films synthesized by spray pyrolysis technique  

NASA Astrophysics Data System (ADS)

Superhydrophobic and transparent zinc oxide (ZnO) thin films were deposited by a simple and cost effective spray pyrolysis technique (SPT) onto the glass substrates at 723 K from an aqueous zinc acetate precursor solution. The solution concentration was varied from 0.1 to 0.4 M and its effect on structural, morphological, wetting and optical properties of ZnO thin films was studied. The synthesized films were found to be polycrystalline, with preferential growth along c-axis. A slight improvement in the crystallite size and texture coefficient is observed as the concentration of the solution is increased. SEM micrographs show the uniform distribution of spherical grains of about 60-80 nm grain size. The films were specular and highly transparent with average transmittance of about 85%. The spectrum shows sharp absorption band edge at 381 nm, corresponding to optical gap of 3.25 eV. The samples of texture coefficient less than 90% and roughness less than 75 nm are hydrophobic and above these values they become superhydrophobic in nature. The hydrophobicity coupled with high transmittance is of great importance in commercial application such as transparent self-cleaning surfaces, anti-fog, anti-snow, fluid microchips and microreactors.

Tarwal, N. L.; Patil, P. S.

2010-10-01

76

Effects of types of drying control chemical additives on the morphologies and electrochemical properties of Li 4Ti 5O 12 anode powders prepared by spray pyrolysis  

Microsoft Academic Search

The various types of drying control chemical additives are applied to control the morphological and electrochemical characteristics of the Li4Ti5O12 powders prepared by spray pyrolysis. The Li4Ti5O12 powders obtained from the spray solutions with formamide, N,N-dimethylformamide, N-methylacetamide and 1,4-dioxane have dense structures and fine sizes. On the other hand, the Li4Ti5O12 powders obtained from the spray solution with glycerol have

Seo Hee Ju; Yun Chan Kang

2010-01-01

77

Magnetic/luminescent core/shell particles synthesized by spray pyrolysis and their application in immunoassays with internal standard  

PubMed Central

Many types of fluorescent nanoparticles have been investigated as alternatives to conventional organic dyes in biochemistry; magnetic beads also have a long history of biological applications. In this work we apply flame spray pyrolysis in order to engineer a novel type of nanoparticle that has both luminescent and magnetic properties. The particles have magnetic cores of iron oxide doped with cobalt and neodymium and luminescent shells of europium-doped gadolinium oxide (Eu:Gd2O3). Measurements by vibrating sample magnetometry showed an overall paramagnetic response of these composite particles. Luminescence spectroscopy showed spectra typical of the Eu ion in a Gd2O3 host—a narrow emission peak centred near 615 nm. Our synthesis method offers a low-cost, high-rate synthesis route that enables a wide range of biological applications of magnetic/luminescent core/shell particles. Using these particles we demonstrate a novel immunoassay format with internal luminescent calibration for more precise measurements. PMID:18974844

Dosev, Dosi; Nichkova, Mikaela; Dumas, Randy K; Gee, Shirley J; Hammock, Bruce D; Liu, Kai; Kennedy, Ian M

2008-01-01

78

Luminescence and afterglow in CaTiO 3:Pr 3+ films deposited by spray pyrolysis  

Microsoft Academic Search

The structural and optical properties of films of CaTiO3:Pr3+ deposited by a spray method are investigated. These films show lower afterglow efficiency than the powdered sample of same composition. To understand this behavior, the possible trapping centers and afterglow mechanisms in CaTiO3:Pr3+ are revisited. It is concluded that the lower afterglow of films is due to a lower number of

P. Boutinaud; E. Pinel; R. Mahiou

2008-01-01

79

Effect of calcination temperature on morphology, crystallinity and electrochemical properties of nano-crystalline metal oxides (Co 3O 4, CuO, and NiO) prepared via ultrasonic spray pyrolysis  

Microsoft Academic Search

Nano-crystalline metal oxides (Co3O4, CuO, and NiO) are synthesized as anode materials for lithium-ion batteries by an ultrasonic spray pyrolysis method. The effects of calcination temperature on the morphology, crystallite size and electrochemical properties of the metal oxides are investigated. X-ray diffraction (XRD) studies show that the crystallite size varies with the final calcination temperature. Scanning electron microscopy (SEM) and

Sung Woo Oh; Hyun Joo Bang; Young Chan Bae; Yang-Kook Sun

2007-01-01

80

Effect of annealing on the properties of Bi doped ZnO thin films grown by spray pyrolysis technique  

NASA Astrophysics Data System (ADS)

The effect of annealing temperature on the structural, optical and electrical properties of transparent and conducting Bi doped ZnO (BZO) films deposited on glass substrate by spray pyrolysis technique was investigated. The BZO thin films were annealed in the temperature range from 450 °C to 550 °C for 4 h in air atmosphere. The grain size of the BZO films increased with increasing annealing temperature. The annealed BZO films were electrically stable and there was a drastic change in the electrical conductivity after annealing. The films annealed at 500 °C showed better conductivity and optical transmittance.

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

2014-11-01

81

Formation of self-assembled quantum dots of iron oxide thin films by spray pyrolysis from non-aqueous medium  

NASA Astrophysics Data System (ADS)

Quantum dots (QDs) of iron oxide have been deposited onto ITO coated glass substrates by spray pyrolysis technique, using ferric chloride (FeCl 3·7H 2O) in non-aqueous medium as a starting material. The non-aqueous solvents namely methanol, ethanol, propanol, butanol and pentanol were used as solvents. The effect of solvents on the film structure and morphology was studied. The structural, morphological, compositional and optical properties were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive analysis of X-rays (EDAX), and optical absorption measurement techniques.

Desai, J. D.; Pathan, H. M.; Min, Sun-Ki; Jung, Kwang-Deog; Joo, Oh-Shim

2006-09-01

82

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

SciTech Connect

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.

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

2013-08-27

83

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

NASA Astrophysics Data System (ADS)

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.

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

2012-05-01

84

Leidenfrost temperature related CVD-like growth mechanism in ZnO-TFTs deposited by pulsed spray pyrolysis  

NASA Astrophysics Data System (ADS)

Zinc oxide thin films were prepared by pulsed spray pyrolysis (SP) from aqueous zinc acetate precursor solution. The deposition behavior of the solution with regard to the pool boiling curve of the solvent was investigated to gain insights of the deposition mechanism which leads to homogeneous and reproducible ZnO layers. The Leidenfrost effect was found to play an important role since the Leidenfrost temperature has to be exceeded to form high quality layers. It is concluded that 3D nucleation of ZnO nano-crystals takes place out of the gaseous phase by a CVD-like process on ITO as well as on SiO2 substrates. Crystal orientation and surface roughness of the zinc oxide layer are found to depend strongly on the substrate. An increasing grain size with film thickness is observed. These findings were utilized to fabricate and investigate the semiconducting properties of the films in ZnO thin film transistors (TFTs). The mobility exceeded 12 cm2 V-1 s-1, the on-set was at 1 V and the on-off current ratio was found to be higher than 108. Hence the morphology and the electrical parameters of the ZnO films deposited by pulsed spray pyrolysis from non-toxic aqueous zinc acetate solution above the Leidenfrost point show excellent properties for electronic applications.

Ortel, Marlis; Wagner, Veit

2013-01-01

85

Characterization of thin CuCo 2O 4 films prepared by chemical spray pyrolysis. Study of their electrochemical stability by ex situ spectroscopic analysis  

Microsoft Academic Search

Pure copper cobalt oxide with spinel structure can be prepared as thin films at 340°C by chemical spray pyrolysis of the metal nitrate aqueous solution over conducting glass. Addition of ammonium nitrate to the sprayed solution increases the crystallization. We report herein the preparation and characterization of such films using X-ray diffraction, FTIR reflectance and transmission spectroscopy, UV-vis spectroscopy, scanning

J. L. Gautier; E. Trollund; E. Ríos; P. Nkeng; G. Poillerat

1997-01-01

86

Effect of Boric Acid Flux and Drying Control Chemical Additive on the Characteristics of Y2O3:Eu Phosphor Particles Prepared by Spray Pyrolysis  

Microsoft Academic Search

Y2O3:Eu phosphor particles with a spherical shape, a fine size, and high brightness under vacuum ultraviolet (VUV) illumination were prepared by spray pyrolysis. The polymeric precursors were needed to modify the spray solution to prepare spherical particles. The use of only flux with the polymeric precursors did not produce dense and spherical Y2O3:Eu particles; that is, the produced particles were

Hye Young Koo; Seo Hee Ju; Seung Kwon Hong; Dae Soo Jung; Yun Chan Kang; Kyeong Youl Jung

2006-01-01

87

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

Microsoft Academic Search

High-density Li4Ti5O12 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 0.5M. The addition of dimethylacetamide to the polymeric spray solutions containing citric acid and ethylene

Seo Hee Ju; Yun Chan Kang

2010-01-01

88

Apparatus and method for spraying liquid materials  

DOEpatents

A method for spraying liquids involving a flow of gas which shears the liquid. A flow of gas is introduced in a converging-diverging nozzle where it meets and shears the liquid into small particles which are of a size and uniformity which can be controlled through adjustment of pressures and gas velocity. 5 figs.

Alvarez, J.L.; Watson, L.D.

1988-01-21

89

Apparatus and method for spraying liquid materials  

DOEpatents

A method for spraying liquids involving a flow of gas which shears the liquid. A flow of gas is introduced in a converging-diverging nozzle where it meets and shears the liquid into small particles which are of a size and uniformity which can be controlled through adjustment of pressures and gas velocity.

Alvarez, Joseph L. (Idaho Falls, ID); Watson, Lloyd D. (Rigby, ID)

1990-01-01

90

Synthesis and characterization of boron-doped NiO thin films produced by spray pyrolysis  

NASA Astrophysics Data System (ADS)

Boron-doped NiO thin films were prepared on glass substrates at 400°C by airbrush spraying method using a solution of nickel nitrate hexahydrate. Their physical properties were investigated as a function of dopant concentration. From X-ray diffraction patterns, it is observed that the films have cubic structure with lattice parameters varying with boron concentration. The morphologies of the films were examined by using scanning electron microscopy, and the grain sizes were measured to be around 30-50 nm. Optical measurements show that the band gap energies of the films first decrease then increase with increasing boron concentration. The resistivities of the films were determined by four point probe method, and the changes in resistivity with boron concentration were investigated.

Alver, U.; Yayka?l?, H.; Kerli, S.; Tanr?verdi, A.

2013-11-01

91

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

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.

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

2007-01-01

92

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)

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.

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

2014-02-01

93

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

SciTech Connect

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.

Martinez, H.M. [Grupo de Materiales con Aplicaciones Tecnologicas, Departamento de Fisica Universidad Nacional de Colombia sede Bogota (Colombia)] [Grupo de Materiales con Aplicaciones Tecnologicas, Departamento de Fisica Universidad Nacional de Colombia sede Bogota (Colombia); Torres, J., E-mail: njtorress@unal.edu.co [Grupo de Materiales con Aplicaciones Tecnologicas, Departamento de Fisica Universidad Nacional de Colombia sede Bogota (Colombia); Lopez Carreno, L.D. [Grupo de Materiales con Aplicaciones Tecnologicas, Departamento de Fisica Universidad Nacional de Colombia sede Bogota (Colombia)] [Grupo de Materiales con Aplicaciones Tecnologicas, Departamento de Fisica Universidad Nacional de Colombia sede Bogota (Colombia); Rodriguez-Garcia, M.E. [Departamento de Nanotecnologia, Centro de Fisica Aplicada y Tecnologia Avanzada, Universidad Nacional Autonoma de Mexico, Campus Juriquilla, Queretaro, Qro., Mexico (Colombia)] [Departamento de Nanotecnologia, Centro de Fisica Aplicada y Tecnologia Avanzada, Universidad Nacional Autonoma de Mexico, Campus Juriquilla, Queretaro, Qro., Mexico (Colombia)

2013-01-15

94

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

NASA Astrophysics Data System (ADS)

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 ?-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.

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

2014-06-01

95

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

NASA Astrophysics Data System (ADS)

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 2×10-3 ? cm.

Karakaya, Seniye; Ozbas, Omer

2013-12-01

96

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

NASA Astrophysics Data System (ADS)

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.

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

2012-10-01

97

Effect of substrate temperature on structure and optical properties of Co3O4 films prepared by spray pyrolysis technique  

NASA Astrophysics Data System (ADS)

Polycrystalline Co3O4 films of spinel cubic phase were prepared by spray pyrolysis on amorphous substrate. The deposition time was kept constant (30min) with variable ranges of substrate temperature (573-723 K). The structural and optical properties of films were studied. The average crystallite size calculated by Scherrer's equation was found to increase as substrate temperature increased. Very small particle size was achieved. Even at the highest deposition temperature, the size did not exceed 11.6nm. The average crystallite size obtained from AFM photos was ranged in from 182 to 248nm which reveals the presence of agglomerates. Optical data were recorded in the wavelength range 300-2500nm. A considerable difference in transmittance was observed for films prepared at different substrate temperatures. The absorption coefficient was measured and then correlated with the photon energy to estimate the energy gap, which was the value of the spinel phase with a direct transition

Abbas, S. Z.; Aboud, A. A.; Irfan, M.; Alam, S.

2014-06-01

98

One-step synthesis of bismuth molybdate catalysts via flame spray pyrolysis for the selective oxidation of propylene to acrolein.  

PubMed

Flame spray pyrolysis (FSP) of Bi(iii)- and Mo(vi)-2-ethylhexanoate dissolved in xylene resulted in various nanocrystalline bismuth molybdate phases depending on the Bi/Mo ratio. Besides ?-Bi2Mo3O12 and ?-Bi2MoO6, FSP gave direct access to the metastable ?-Bi2Mo2O9 phase with high surface area (19 m(2) g(-1)). This phase is normally only obtained at high calcination temperatures (>560 °C) resulting in lower surface areas. The ?-phase was stable up to 400 °C and showed superior catalytic performance compared to ?- and ?-phases in selective oxidation of propylene to acrolein at temperatures relevant for industrial applications (360 °C). PMID:25350295

Schuh, K; Kleist, W; Høj, M; Trouillet, V; Jensen, A D; Grunwaldt, J-D

2014-12-18

99

Effect of the flame temperature on the characteristics of zirconium oxide fine particle synthesized by flame assisted spray pyrolysis  

NASA Astrophysics Data System (ADS)

Zirconium oxide fine particles were synthesized by flame assisted spray pyrolysis using zirconium chloride solution as precursor. Propane gas and air were used as a fuel and an oxidizer, respectively. The ratio of flow rate of oxidizer and fuel was maintained constant at 10:1 to ensure a complete combustion. Increasing fuel flow rate led to the increase of temperature distribution in the flame reactor. The intensity of XRD patterns increased with temperature and precursor concentration. Phase composition of zirconium oxide produced by this process consisted of monoclinic and tetragonal phases. The volume fraction of monoclinic phase of zirconium oxide increased with temperature and precursor concentration. The morphology particles observed by SEM resulted in spherical particles with size in the submicron range depending on the precursor concentration.

Widiyastuti, W.; Machmudah, Siti; Nurtono, Tantular; Winardi, Sugeng

2013-09-01

100

Synthesis and characterization of earth abundant and nontoxic metal chalcogenides produced via aerosol spray pyrolysis for photovoltaic applications  

NASA Astrophysics Data System (ADS)

A novel synthesis technique for the production of copper zinc tin sulfide (CZTS) nanocrystals has been developed using aerosol spray pyrolysis. CZTS is a quaternary semiconducting material that shows promise as a replacement to common semiconductors such as CdTe and CIGS for use in photovoltaic devices. CIGS is currently being commercialized in the photovoltaic industry, but rare and expensive indium and gallium components threaten its long term viability. CZTS looks to be one of the best alternatives to CIGS with all earth abundant and non-toxic materials and recent impressive gains in efficiency. A number of synthesis techniques have been thoroughly studied and detailed previously. In our novel approach, we synthesis single phase nanocrystals, starting with zinc, copper, and tin diethyldithiocarbamate precursors in a toluene solvent. The precursor solution is aerosolized using an ultrasonic nebulizer wherein the droplets are vacuumed through a tube furnace and nucleation occurs. We reproducibly synthesize kesterite, Cu2ZnSnS4, nanocrystals. This technique continuously converts the chemical precursor into high-purity nanopowder with a production rate of ~50 mg/hour for an un-optimized, lab-scale reactor. Using the same precursor chemistry, we have also been able to deposit high-quality CZTS thin films directly onto Mo-coated Swiss glass substrates using the aerosol spray pyrolysis technique. A thorough discussion of the current photovoltaic field, the processing parameters and challenges of nanocrystal and thin film production, and the experimental results will be presented. Characterization via Raman spectroscopy, EDS, XRD, TEM and XPS will be offered along with future recommendations and considerations.

Davis, Patrick John

101

Smokeless pyrolysis furnace with micro-ramped temperature controlled by water-spray  

SciTech Connect

This patent describes an improvement in a pyrolysis furnace. It comprises: a main chamber, a main burner to directly heat air ducted into the chamber, a throat near the top of the main chamber through which throat organic vapor volatilized by pyrolysis of burnables leaves the main chamber, the throat having an area, and the main chamber having a volume which are related such that their ratio is always greater than the critical vent number 0.0003/ft, an afterburner chamber provided with an afterburner to incinerate the organic vapor downstream of the throat, a single temperature sensing means (TC) located within the main chamber to sense the temperature of gases above the metal parts within the chamber, and, an exhaust stack through which incinerated vapor is vented.

Koptis, R.A.; Heran, R.F.

1990-11-20

102

A method for the interpretation of pyrolysis-mass spectra of polyesters  

Microsoft Academic Search

A new method for the interpretation of pyrolysis-mass spectra of polyesters is described. The method is based on the use of table of pyrolysis-mass spectral data of polyesters. It has two steps: first, the examination of the unknown pyrolysis-mass spectrum in order to extract information about the relationship of specific ion masses with particular polyester structures; second the recongnition and

C. G. Georgakopoulos; M. Statheropoulos; G. Parissakis; G. Montaudo

1995-01-01

103

Effect of doping concentration on the properties of aluminium doped zinc oxide thin films prepared by spray pyrolysis for transparent electrode applications  

Microsoft Academic Search

Zinc oxide possesses many interesting properties, such as modifiable conductivity, wide band gap, high excitonic binding energy, piezo-electric polarisation and cathodoluminiscence. In this study transparent conducting aluminium doped zinc oxide (ZnO:Al) thin films were deposited on float glass substrates by tailor made spray pyrolysis with adaptation for measuring the actual temperature of the substrate surface during deposition. The films were

C. M. Muiva; T. S. Sathiaraj; K. Maabong

2011-01-01

104

Effects of preparation conditions on the electrochemical and morphological characteristics of Li 4Ti 5O 12 powders prepared by spray pyrolysis  

Microsoft Academic Search

Li4Ti5O12 anode powders were prepared by post-treatment of the precursor powders obtained by spray pyrolysis at various preparation conditions. The precursor powders had fine size, narrow size distribution, dense inner structure and homogeneous composition when the flow rate of the carrier gas and the preparation temperature were 10lmin?1 and 800°C. The spherical shapes of the precursor powders obtained at the

Seo Hee Ju; Yun Chan Kang

2009-01-01

105

Effect of organic acid on the electrochemical properties of Li 4Ti 5O 12\\/C composite powders synthesized by spray pyrolysis  

Microsoft Academic Search

A composite powder of Li4Ti5O12 and carbon (LTO\\/C) was synthesized by spray pyrolysis using an aqueous solution of Li and Ti with an organic acid. As-prepared LTO\\/C particles had spherical morphology and nonaggregation characteristics. They also had a particle size of approximately 1?m with a broad size distribution. As-prepared LTO\\/C powders were crystallized to have a spinel structure. The addition

Takashi Ogihara; Motofumi Yamada; Atsushi Fujita; Shinsuke Akao; Kenichi Myoujin

2011-01-01

106

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

SciTech Connect

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.

Ortel, Marlis; Balster, Torsten; Wagner, Veit [School of Engineering and Science, Jacobs University Bremen, Campus Ring 1, 28759 Bremen (Germany)

2013-12-21

107

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

NASA Astrophysics Data System (ADS)

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, CO3, 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 × 1017 eV-1 cm-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 cm2/V s, the subthreshold slope was 0.3 V dec-1, and an on-set close to the ideal value of 0 V was achieved.

Ortel, Marlis; Balster, Torsten; Wagner, Veit

2013-12-01

108

Flash Pyrolysis -A Powerful Method for Characterization of Polymers Helge Egsgaard  

E-print Network

by, e.g. gas chromatography ­ mass spectrometry. The method is a powerful strategyFlash Pyrolysis - A Powerful Method for Characterization of Polymers Helge Egsgaard Biosystems Department Risø National Laboratory DK-4000 Roskilde, Denmark The rational behind the pyrolysis technique

109

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

NASA Astrophysics Data System (ADS)

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 ?m - 2.2 ?m 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.

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

2013-09-01

110

Preparation of Li4Ti5O12 yolk-shell powders by spray pyrolysis and their electrochemical properties.  

PubMed

We have reported for the first time the preparation of yolk-shell-structured Li4Ti5O12 powders for use as anode materials in lithium-ion batteries. One Li4Ti5O12 yolk-shell-particle powder is directly formed from each droplet containing lithium, titanium, and carbon components inside the hot wall reactor maintained at 900?°C. The precursor Li4Ti5O12 yolk-shell-particle powders, which are directly prepared by spray pyrolysis, have initial discharge and charge capacities of 155 and 122?mA?h?g(-1) , respectively, at a current density of 175?mA?g(-1) . Post-treatment of the yolk-shell-particle powders at temperatures of 700 and 800?°C improves the initial discharge and charge capacities. The initial discharge capacities of the Li4Ti5O12 powders with a yolk-shell structure and a dense structure post-treated at 800?°C are 189 and 168?mA?h?g(-1) , respectively. After 100 cycles, the corresponding capacities are 172 and 152?mA?h?g(-1) , respectively (retentions of 91 and 90%). PMID:24282098

Yang, Kwang Min; Ko, You Na; Yun, Jung-Yeul; Kang, Yun Chan

2014-02-01

111

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

NASA Astrophysics Data System (ADS)

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.

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

2014-08-01

112

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

NASA Astrophysics Data System (ADS)

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.

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

2014-09-01

113

Effects of N,N-Dimethylacetamide as Drying Control Chemical Additive on Characteristics of Zn2SiO4:Mn,Ba Phosphor Powders Prepared by Spray Pyrolysis  

Microsoft Academic Search

Zn2SiO4:Mn,Ba phosphor powders were prepared by ultrasonic spray pyrolysis from spray solutions with and without a drying control chemical additive (DCCA). N,N-dimethylacetamide (DMA) used as the DCCA affected the morphology, surface area, mean crystallite size, and photoluminescence intensity of Zn2SiO4:Mn,Ba phosphor powders. The phosphor powders prepared from a spray solution with an optimum concentration of DMA of 1 M had

Hye Young Koo; Sang Ho Lee; Yun Chan Kang

2008-01-01

114

New methods of nozzle attachment to FRP spray headers  

SciTech Connect

The traditional method of attaching spray nozzles to FRP spray headers in the absorber tower of a wet limestone system has been through the use of 150 lb. Flanges. This paper will illustrate two additional methods (grooved adapters & adhesive bonded nozzles) and will demonstrate the cost saving associated versus the flanged option, as well as the advantages and disadvantages of each system.

Boucher, E.J. [FRP Associates, Inc., Avon, CT (United States)

1995-06-01

115

Effects of synthesis conditions on Curie temperature of La0.75Sr0.25MnO3 fine particles formed by ultrasonic spray pyrolysis  

NASA Astrophysics Data System (ADS)

Manganese perovskite La0.75Sr0.25MnO3 (LSM) fine particles were synthesized by an ultrasonic spray pyrolysis method at various synthesis temperatures (Ts), reaction times (tr), and source solution concentrations (Ctotal) to clarify the effects of these synthesis conditions on their Curie temperature Tc and maximum particle temperature attained by magnetic heating at Thmax. At constant Ctotal, the Tc of synthesized LSM particles was increased from 288.6 to 363.5 K (15.6 to 90.5 °C) by increasing Ts from 1073 to 1627 K (800 to 1400 °C), and was increased from 281.8 to 339 K (8.89 to 66 °C) by increasing tr from 2.4 to 19 s. When the AC magnetic field was applied, the particles generated heat, and the particle temperature Th increased with time for t < about 2 min, and then attained constant Thmax near Tc. Thmax increased with increasing Tc. The LSM particles produced at Ts = 1213 K, Ctotal = 0.5 mol L-1, and tr = 9.4 s had Thmax = 316.6 K (43.6 °C), which is within the temperature range of 316-318 K (43-45 °C) for hyperthermia therapy for cancer.

Kinoshita, Takuya; Furuyabu, Takamitsu; Adachi, Motoaki

2014-10-01

116

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

NASA Astrophysics Data System (ADS)

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.

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

2013-02-01

117

Spray Beam Analysis in Vacuum Spray Method for Deposition of Thin Organic Films  

NASA Astrophysics Data System (ADS)

We report the investigation of a spray beam and the initial stage of thin-film preparation in a vacuum spray method. As the key parts, two types of orifice plate with pinholes with diameters of 10 and 20 µm were used in the spray nozzle. The spray solution beam in a vacuum chamber was irradiated with a green laser. By measuring the length of the laser-scattered part, the divergence angle of the spray beam and the relationship between the beam width and spray pressure were investigated. After diluted poly[2-methoxy-5-(2'-ethylhexoxy)-1,4-phenylenevinylene] (MEH-PPV) in a chloroform solution was injected onto the heated substrates in a short time period, the MEH-PPV particles on the substrates were analyzed by optical microscopy and atomic force microscopy (AFM). Compared with the orifice plate with a pinhole with a diameter of 20 µm, the 10-µm-orifice plate generated a spray beam with a big divergence angle, and the MEH-PPV particles on the substrate were smaller and more uniform in size.

Mo, Xiaoliang; Mizokuro, Toshiko; Tanigaki, Nobutaka; Hiraga, Takashi; Umehara, Noboru; Takagi, Kazuyoshi; Yamamoto, Sumio

2008-01-01

118

UV and VUV characteristics of (YGd){sub 2}O{sub 3}:Eu phosphor particles prepared by spray pyrolysis from polymeric precursors  

SciTech Connect

Red-emitting (YGd){sub 2}O{sub 3}:Eu phosphor particles, with high luminescence efficiency under vacuum ultraviolet (VUV) and ultraviolet (UV) excitation, were prepared by a large-scale spray pyrolysis process. To control the morphology of phosphor particles under severe preparation conditions, spray solution with polymeric precursors were introduced in spray pyrolysis. The prepared (YGd){sub 2}O{sub 3}:Eu phosphor particles had spherical shape and filled morphology even after post-treatment irrespective of Gd/Y ratio. In the case of solution with polymeric precursors, long polymeric chains formed by esterification reaction in a hot tubular reactor; the droplets turned into viscous gel, which retarded the precipitation of nitrate salts and promoted the volume precipitation of droplets. The brightness of (YGd){sub 2}O{sub 3}:Eu phosphor particles increased with increasing gadolinium content, and the Gd{sub 2}O{sub 3}:Eu phosphor had the highest luminescence intensity under UV and VUV excitation. The maximum peak intensity of Gd{sub 2}O{sub 3}:Eu phosphor particles under UV and VUV were 118 and 110% of the commercial Y{sub 2}O{sub 3}:Eu phosphor particles, respectively.

Kim, E.J.; Kang, Y.C.; Park, H.D.; Ryu, S.K

2003-02-20

119

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

NASA Astrophysics Data System (ADS)

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 (5.60×10-2 ? cm) and hole concentration (3.15×1018 cm-3) for the best dual acceptor doped film is 6 at.%. It has been predicted that (NaZn-NO) 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.

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

2014-01-01

120

Chemical spray pyrolysis deposition and characterization of p-type CuCr 1? x Mg x O 2 transparent oxide semiconductor thin films  

Microsoft Academic Search

A chemical spray pyrolysis technique for deposition of p-type Mg-doped CuCrO2 transparent oxide semiconductor thin films using metaloorganic precursors is described. As-deposited films contain mixed spinel CuCr2O4 and delafossite CuCrO2 structural phases. Reduction in spinel CuCr2O4 fraction and formation of highly crystalline films with single phase delafossite CuCrO2 structure is realized by annealing at temperatures ?700°C in argon. A mechanism

S. H. Lim; Suma Desu; A. C. Rastogi

2008-01-01

121

Photoelectrochemical and structural characterization of carbon-doped In2O3 and carbon-doped WO3 films prepared via spray pyrolysis  

Microsoft Academic Search

Carbon-doped In2O3 and carbon-doped WO3 films were produced using a spray pyrolysis methodology with octanoic acid as the carbon dopant source. C-doped and undoped In2O3 films showed a cubic polycrystalline In2O3 structure, and C-doped and undoped WO3 films displayed a monoclinic polycrystalline WO3 structure. C-doped In2O3 and WO3, compared to their corresponding undoped materials, showed increased absorption in the 350-550

Yanping Sun; Rina Rajpura; Daniel Raftery

2009-01-01

122

Preparation of BaTiO3 nanoparticles by combustion spray pyrolysis Sangjin Leea  

E-print Network

chemical vapor condensa- tion method using a combustion flame to synthesize nano- sized particles, and Choi to be the result of a chemical segregation during precipitation [8]. Here we describe a new wet chemical process [17] offered a flame method using a CO2 laser to make nanometer particles. However, these systems were

Messing, Gary L.

123

Effect of different dopant elements (Al, Mg and Ni) on microstructural, optical and electrochemical properties of ZnO thin films deposited by spray pyrolysis (SP)  

NASA Astrophysics Data System (ADS)

In the present work we studied the influence of the dopant elements and concentration on the microstructural and electrochemical properties of ZnO thin films deposited by spray pyrolysis. Transparent conductive thin films of zinc oxide (ZnO) were prepared by the spray pyrolysis process using an aqueous solution of zinc acetate dehydrate [Zn(CH3COO)2·2H2O] on soda glass substrate heated at 400 ± 5 °C. AlCl3, MgCl2 and NiCl2 were used as dopant. The effect of doping percentage (2-4%) has been investigated. Afterwards the samples were thermally annealed in an ambient air during one hour at 500 °C. X-ray diffraction showed that films have a wurtzite structure with a preferential orientation along the (0 0 2) direction for doped ZnO. The lattice parameters a and c are estimated to be 3.24 and 5.20 ?, respectively. Transmission allowed to estimate the band gaps of ZnO layers. The electrochemical studies revealed that the corrosion resistance of the films depended on the concentration of dopants.

Benzarouk, Hayet; Drici, Abdelaziz; Mekhnache, Mounira; Amara, Abdelaziz; Guerioune, Mouhamed; Bernède, Jean Christian; Bendjffal, Hacen

2012-09-01

124

Method of producing thermally sprayed metallic coating  

DOEpatents

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.

Byrnes, Larry Edward (Rochester Hills, MI); Kramer, Martin Stephen (Clarkston, MI); Neiser, Richard A. (Albuquerque, NM)

2003-08-26

125

Method and apparatus for spraying molten materials  

DOEpatents

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.

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

1996-06-25

126

Method and apparatus for spraying molten materials  

DOEpatents

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.

Glovan, Ronald J. (Butte, MT); Tierney, John C. (Butte, MT); McLean, Leroy L. (Butte, MT); Johnson, Lawrence L. (Butte, MT); Nelson, Gordon L. (Butte, MT); Lee, Ying-Ming (Butte, MT)

1996-01-01

127

Flame Spray Pyrolysis for Finding Multicomponent Nanomaterials with Superior Electrochemical Properties in the CoOx -FeOx System for Use in Lithium-Ion Batteries.  

PubMed

High-temperature flame spray pyrolysis is employed for finding highly efficient nanomaterials for use in lithium-ion batteries. CoOx -FeOx nanopowders with various compositions are prepared by one-pot high-temperature flame spray pyrolysis. The Co and Fe components are uniformly distributed over the CoOx -FeOx composite powders, irrespective of the Co/Fe mole ratio. The Co-rich CoOx -FeOx composite powders with Co/Fe mole ratios of 3:1 and 2:1 have mixed crystal structures with CoFe2 O4 and Co3 O4 phases. However, Co-substituted magnetite composite powders prepared from spray solutions with Co and Fe components in mole ratios of 1:3, 1:2, and 1:1 have a single phase. Multicomponent CoOx -FeOx powders with a Co/Fe mole ratio of 2:1 and a mixed crystal structure with Co3 O4 and CoFe2 O4 phases show high initial capacities and good cycling performance. The stable reversible discharge capacities of the composite powders with a Co/Fe mole ratio of 2:1 decrease from 1165 to 820?mA?h?g(-1) as the current density is increased from 500 to 5000?mA?g(-1) ; however, the discharge capacity again increases to 1310?mA?h?g(-1) as the current density is restored to 500?mA?g(-1) . PMID:25065898

Kim, Jung Hyun; Lee, Jong-Heun; Kang, Yun Chan

2014-10-01

128

Effect of Boric Acid Flux and Drying Control Chemical Additive on the Characteristics of Y2O3:Eu Phosphor Particles Prepared by Spray Pyrolysis  

NASA Astrophysics Data System (ADS)

Y2O3:Eu phosphor particles with a spherical shape, a fine size, and high brightness under vacuum ultraviolet (VUV) illumination were prepared by spray pyrolysis. The polymeric precursors were needed to modify the spray solution to prepare spherical particles. The use of only flux with the polymeric precursors did not produce dense and spherical Y2O3:Eu particles; that is, the produced particles were very porous. The addition of both a drying control chemical additive (DCCA) and boric acid to a spray solution containing polymeric precursors was found to produce Y2O3:Eu phosphor particles with a dense structure while maintaining the spherical morphology. According to X-ray diffraction (XRD) analysis, the DCCA induced an enhancement of crystallinity. The use of boric acid flux improved the photoluminescence (PL) intensity under VUV illumination. In addition, the use of both boric acid flux and a DCCA with polymeric precursors further improved the PL intensity owing to the enhancement of the morphology and the crystallinity.

Koo, Hye Young; Ju, Seo Hee; Hong, Seung Kwon; Jung, Dae Soo; Kang, Yun Chan; Jung, Kyeong Youl

2006-12-01

129

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

PubMed

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. PMID:22835770

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

2012-09-30

130

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

NASA Astrophysics Data System (ADS)

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-Cu) known for their catalytic properties. These materials then serve as baseline studies for ternary systems, such as Al:(Ni-Co)O, or Al(Ni-Cu)O likely to offer superior catalytic properties because of the relatively high SSA Al2O3. The final chapter returns to photonic materials, in the MgO-Y2O 3 system targeting transparent ceramics through select compositions along the tie-line. The work presented here builds on the MgAl2O 4 spinel material and continues to develop the processing techniques required to achieve transparent nano-grained ceramic materials. Thus the overall goal of this dissertation was to systematically produce novel nano-oxide materials and characterized their material properties. The first chapters focus on solid solutions at low Ni or Co amounts that form phase pure spinels outside the expected composition range, at 21-22 mol % NiO and CoO. Additionally, (NiO)0.22(Al2O3) 0.78 was found to be very stable, as it did not convert to alpha-Al 2O3 plus cubic-NiO on heating to 1200°C for 10 h. The last chapter is a preliminary step toward identifying optimal Y 2O3-MgO powders that can be transparent ceramics. Ball milling led to much higher adsorption of surface species. Preliminary sintering studies of the this system showed that vacuum has the largest effect on lowering the temperature of maximum shrinkage rate by ? 80°C.

Azurdia, Jose Antonio

131

Room temperature electroluminescence from the n-ZnMgO/ZnO/p-ZnMgO heterojunction device grown by ultrasonic spray pyrolysis  

NASA Astrophysics Data System (ADS)

The heterojunction light-emitting diode with n-Zn 0.8Mg 0.2O/ZnO/p-Zn 0.8Mg 0.2O structure was grown on single-crystal GaAs(1 0 0) substrate by a simple process of ultrasonic spray pyrolysis. The p-type Zn 0.8Mg 0.2O layer was obtained by N-In codoping. A distinct visible electroluminescence with a dominant emission peak centered at ˜450 nm was observed at room temperature from the heterojunction structure under forward bias conditions. The origin of electroluminescence emission was supposed to be attributed to a radiative recombination through deep-level defects in the ZnO active layer. The result reported here provides convincing evidence that ZnO based light-emitting devices can be realized at extremely low cost.

Bian, Jiming; Liu, Weifeng; Liang, Hongwei; Hu, Lizhong; Sun, Jingchang; Luo, Yingmin; Du, Guotong

2006-10-01

132

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

NASA Technical Reports Server (NTRS)

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.

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

2003-01-01

133

Effect of Li3+ heavy ion irradiation on the Mo doped In2O3 thin films prepared by spray pyrolysis technique  

NASA Astrophysics Data System (ADS)

The high visible-near infrared transparent and high carrier mobility (?) Mo doped (0.5 at%) indium oxide (IMO) films were deposited by the spray pyrolysis technique. The deposited films were irradiated by 50 MeV Li3+ ions with different fluences of 1 × 1011, 1 × 1012 and 1 × 1013 ions cm-2. X-ray diffraction analysis confirmed the cubic bixbyite structure of indium oxide. A fascinating feature is that the ion irradiation process has introduced a fraction of the molybdenum oxide phase. The ? of as-deposited IMO films is decreased from ~122.4 to 93.3 cm2 V-1 s-1, following the ion irradiation. The theoretically calculated ? and carrier density values were correlated with those measured experimentally. The transport mechanism has been analysed based on the ionized and neutral impurity scattering centres. The average transmittance (400-2500 nm) of the as-deposited IMO films is decreased from 83% to 60% following irradiation.

Parthiban, S.; Elangovan, E.; Ramamurthi, K.; Kanjilal, D.; Asokan, K.; Martins, R.; Fortunato, E.

2011-03-01

134

High electron mobility thin-film transistors based on Ga2O3 grown by atmospheric ultrasonic spray pyrolysis at low temperatures  

NASA Astrophysics Data System (ADS)

We report on thin-film transistors based on Ga2O3 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 Ga2O3 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 Ga2O3 films show n-type conductivity with the maximum electron mobility of ˜2 cm2/V s.

Thomas, Stuart R.; Adamopoulos, George; Lin, Yen-Hung; Faber, Hendrik; Sygellou, Labrini; Stratakis, Emmanuel; Pliatsikas, Nikos; Patsalas, Panos A.; Anthopoulos, Thomas D.

2014-09-01

135

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

NASA Technical Reports Server (NTRS)

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.

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

2003-01-01

136

Fabrication and characterization of Cu 2ZnSnS 4 thin films deposited by spray pyrolysis technique  

Microsoft Academic Search

We have investigated synthesis conditions and some properties of sprayed Cu2ZnSnS4 (CZTS) thin films in order to determine the best preparation conditions for the realization of CZTS based photovoltaic solar cells. The thin films are made by means of spraying of aqueous solutions containing copper chloride, zinc chloride, tin chloride and thiourea on heated glass substrates at various temperatures. In

N. Kamoun; H. Bouzouita; B. Rezig

2007-01-01

137

Method for the gasification of carbonaceous matter by plasma arc pyrolysis  

Microsoft Academic Search

Apparatus and method for gasification of carbonaceous matter by plasma arc pyrolysis are disclosed. In one embodiment, a refractory-lined furnace is provided with a depression along its base for holding a pool of molten metal which acts as the external electrode for a bank of long arc column plasma torches which provide a heat mass for the process. The plasma

Camacho

1980-01-01

138

Structural, electrical and optical properties of nanostructured Cd1-xFexS thin films deposited by chemical spray pyrolysis technique  

NASA Astrophysics Data System (ADS)

Multi-component nanostructured thin films of Cd1-xFexS were successfully deposited onto glass substrates from aqueous solutions of ferric chloride, cadmium chloride and thiourea using chemical spray pyrolysis technique. The structural, compositional and morphological studies were carried out by using X-ray diffractometer (XRD), energy dispersive X-ray analysis (EDAX) and scanning electron microscopy (SEM) and atomic force microscopy (AFM) respectively. The structural study revealed that, CdS, FeS and Cd1-xFexS films are nanocrystalline in nature with hexagonal lattice. The optical characterization shows that the band gap of the spray deposited CdS film is 2.20 eV and it increases with ‘x' and becomes 2.44 eV for FeS. The electrical resistivity of Cd1-xFexS thin films is of the order of 106 ? cm and shows variation depending on ‘x'. The thermo-emf measurement confirms n-type conductivity of Cd1-xFexS thin films.

Ibrahim, S. G.; Ubale, A. U.

2014-11-01

139

A Probability Density Function Method for Modelling Liquid Fuel Sprays  

Microsoft Academic Search

A stochastic model is proposed for modelling the turbulent dispersion of liquid fuel sprays. The approach adopted is based\\u000a on the evolution equation for the joint probability density function (PDF) of the droplet properties. Turbulent dispersion\\u000a is described by Langevin's equation in which a Weiner process is used to represent the stochastic force term. The method leads\\u000a to plausible results

W. P. Jones; D.-H. Sheen

2000-01-01

140

Preparation of pyrolysis reference samples: evaluation of a standard method using a tube furnace.  

PubMed

A new, simple method for the reproducible creation of pyrolysis products from different materials that may be found at a fire scene is described. A temperature programmable steady-state tube furnace was used to generate pyrolysis products from different substrates, including softwoods, paper, vinyl sheet flooring, and carpet. The temperature profile of the tube furnace was characterized, and the suitability of the method to reproducibly create pyrolysates similar to those found in real fire debris was assessed. The use of this method to create proficiency tests to realistically test an examiner's ability to interpret complex gas chromatograph-mass spectrometric fire debris data, and to create a library of pyrolsates generated from materials commonly found at a fire scene, is demonstrated. PMID:22220974

Sandercock, P Mark L

2012-05-01

141

Effects of N,N-Dimethylacetamide as Drying Control Chemical Additive on Characteristics of Zn2SiO4:Mn,Ba Phosphor Powders Prepared by Spray Pyrolysis  

NASA Astrophysics Data System (ADS)

Zn2SiO4:Mn,Ba phosphor powders were prepared by ultrasonic spray pyrolysis from spray solutions with and without a drying control chemical additive (DCCA). N,N-dimethylacetamide (DMA) used as the DCCA affected the morphology, surface area, mean crystallite size, and photoluminescence intensity of Zn2SiO4:Mn,Ba phosphor powders. The phosphor powders prepared from a spray solution with an optimum concentration of DMA of 1 M had a finer size and narrower size distribution than those prepared from a spray solution without DMA. The mean crystallite size of the phosphor powders was changed from 37 to 44 nm depending on the concentration of DMA added to the spray solutions. The Brunauer-Emmett-Teller (BET) surface areas of the phosphor powders prepared from spray solutions with concentrations of DMA of 0.5, 1, and 3 M were 5.1, 3.2, and 2.1 m2/g, respectively. The phosphor powders prepared from the spray solution with an optimum concentration of DMA of 1 M had an 8% higher photoluminescence intensity than the commercial product.

Koo, Hye Young; Lee, Sang Ho; Kang, Yun Chan

2008-09-01

142

ZnO and Al-doped ZnO thin films prepared by spray pyrolysis for ethanol gas sensing  

Microsoft Academic Search

Chemically sprayed aluminum-doped ZnO (1% Al) and undoped ZnO thin films were deposited on glass substrates at T = 420 °C. The thin films are characterized by X-ray diffraction and scanning electron microscopy. The characterization results show that all the compounds are wurtzite with hexagonal structure (0 0 2). They are well crystallized and the grain size is (e =

Y. Bakha; K. M. Bendimerad; S. Hamzaoui

2011-01-01

143

Method and apparatus for atomization and spraying of molten metals  

DOEpatents

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.

Hobson, David O. (Oak Ridge, TN); Alexeff, Igor (Oak Ridge, TN); Sikka, Vinod K. (Clinton, TN)

1990-01-01

144

Method and apparatus for atomization and spraying of molten metals  

DOEpatents

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.

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

1988-07-19

145

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

NASA Astrophysics Data System (ADS)

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.

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

2012-03-01

146

Sn-Doped In2O3 Nanocrystalline Thin Films Deposited by Spray Pyrolysis: Microstructural, Optical, Electrical, and Formaldehyde-Sensing Characteristics  

NASA Astrophysics Data System (ADS)

Undoped and Sn-doped (1, 1.5 and 2 at.%) indium oxide (In2O3) thin films have been grown by the chemical spray pyrolysis technique on cleaned glass substrates using indium nitrate [In(NO3)3] and stannic tetrachloride hydrated (SnCl4·5H2O) as the host and dopant precursors, respectively, and deionized water as the solvent. Structural characterization using x-ray diffraction reveals that the films possess cubic structure, with the average crystallite size in the range 10-14 nm. The surface morphology and roughness of the films have been investigated by means of an atomic force microscope. UV-Vis measurements indicate an enhancement in the optical transmittance in the visible region on Sn doping. Further, the doping effect has been found to substantially reduce the electrical resistance to a few orders of magnitude of the undoped In2O3 film. We report a simultaneous improvement in both the optical and electrical properties of indium oxide thin film due to the doping of Sn ions. These results indicate that Sn-doped In2O3 thin film can be a potential candidate for use in various optoelectronic devices. Among all the films examined, the 1 at.% Sn-doped film shows the maximum response (~91%) at 300 °C for 80 ppm concentration of formaldehyde in air.

Pramod, N. G.; Pandey, S. N.; Sahay, P. P.

2013-08-01

147

Effect of Sb dopant on the structural, optical and electrical properties of SnS thin films by spray pyrolysis technique  

NASA Astrophysics Data System (ADS)

Thin films of antimony doped tin sulphide (SnS:Sb) with different antimony concentrations have been prepared by the spray pyrolysis technique at the substrate temperature of 350 °C. The physical properties of the films were studied as a function of increase in antimony dopant concentration (up to 10 at.%). The films were characterized by different techniques to study their structural, optical and electrical properties. The X-ray diffraction analysis revealed that the films were polycrystalline in nature and having orthorhombic crystal structure with a preferred orientation in (1 1 1) direction. Due to Sb doping, the crystalline quality and the preferential orientation of SnS films were improved up to 6 at.% of doping concentration. However, when doping concentration was increased above 6 at.%, the crystalline quality and the preferential orientation of SnS films was deteriorated. Atomic force microscopy images revealed that the surface roughness of the films increased due to Sb doping. Optical measurements showed that the band gap values decreased from 1.60 eV to 1.15 eV with increase in Sb concentration. The photoluminescence spectra displayed that all the samples have an emission peak centered at 760 nm. At 6 at.% of Sb doping, the film has the lowest resistivity of 2.598 × 10-2 ? cm while the carrier concentration was high.

Santhosh Kumar, K.; Manoharan, C.; Dhanapandian, S.; Gowri Manohari, A.

2013-11-01

148

Tin-Incorporation Induced Changes in the Microstructural, Optical, and Electrical Behavior of Tungsten Oxide Nanocrystalline Thin Films Grown Via Spray Pyrolysis  

NASA Astrophysics Data System (ADS)

Undoped and Sn-doped WO3 thin films were grown on cleaned glass substrates by chemical spray pyrolysis, using ammonium tungstate (NH4)2WO4 as the host precursor and tin chloride (SnCl4·5H2O) as the source of dopant. The XRD spectra confirm the monoclinic structure with a sharp narrow peak along (200) direction along with other peaks of low relative intensities for all the samples. On Sn doping, the films exhibit reduced crystallinity relative to the undoped film. The standard deviation for relative peak intensity with dopant concentration shows enhancement in heterogeneous nucleation growth. As evident from SEM images, on Sn doping, appearance of island-like structure (i.e., cluster of primary crystallites at few places) takes place. The transmittance has been found to decrease in all the Sn-doped films. The optical band gap has been calculated for both direct and indirect transitions. On Sn doping, the direct band gap shows a red shift and becomes 2.89 eV at 2 at.% doping. Two distinct peaks, one blue emission at 408 nm and other green emission at 533 nm, have been found in the PL spectra. Electrical conductivity has been found to increase with Sn doping.

Mukherjee, Ramnayan; Prajapati, C. S.; Sahay, P. P.

2014-08-01

149

Third harmonic generation in undoped and X doped ZnO films (X: Ce, F, Er, Al, Sn) deposited by spray pyrolysis  

NASA Astrophysics Data System (ADS)

There is a current interest in research of wide band gap semiconductor materials for the purposes of third order nonlinear optical properties in view of optoelectronics applications. Materials for nonlinear optics should present important changes of nonlinear intensity, dependence on changes of nonlinear refractive index, short response time, and weak absorption losses. We report the results of the third order nonlinear optical susceptibilities of undoped and doped (cerium, fluorine, erbium, aluminum, and tin) zinc oxide films using the third harmonic generation technique at 1064 nm wavelength region in picoseconds regime. Thin films were grown on glass substrate by the spray pyrolysis technique at different temperatures of substrates and characterized by using the x-ray diffraction, scanning electron microscope, transmission, and photoluminescence. A strong third harmonic signal was obtained from the studied films with a good crystallinity and roughness. We have found that at high conductivity, there is a big conversion of the third harmonic signal at different dopants and at an appropriate concentration. We might say that the morphology and the crystalline quality of the films are the main factors for this high conversion.

Sofiani, Zouhair; Sahraoui, Bouchta; Addou, Mohammed; Adhiri, Rahma; Lamrani, Mehdi Alaoui; Dghoughi, Leila; Fellahi, Nabil; Derkowska, Beata; Bala, Waclaw

2007-03-01

150

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

USGS Publications Warehouse

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.

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

2012-01-01

151

Method and apparatus for pyrolysis of atactic polypropylene  

DOEpatents

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.

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

1986-09-23

152

Colloidal spray method for low cost thin coating deposition  

DOEpatents

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.

Pham, Ai-Quoc (San Jose, CA); Glass, Robert S. (Livermore, CA); Lee, Tae H. (Naperville, IL)

2002-01-01

153

Spray automated balancing of rotors: Methods and materials  

NASA Technical Reports Server (NTRS)

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.

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

1988-01-01

154

Microstructure and tribological properties of stainless steel coatings sprayed by two methods based on spraying  

Microsoft Academic Search

In this work, the microstructure and sliding wear behaviors of stainless steel (AISI 420) coatings prepared by electro-thermal explosion directional spraying (EEDS) and high velocity arc spraying (HVAS) were comparatively investigated. Results show that the EEDS coatings possess more compact microstructure, higher nano-hardness and nano-elastic modulus, finer bond and better wear resistance than the HVAS coatings. The dominant wear mechanism

Guo Jin; Bin-shi Xu; Hai-dou Wang; Qing-fen Li; Shi-cheng Wei

2007-01-01

155

High-capacity cathodes for lithium-ion batteries from nanostructured LiFePO4 synthesized by highly-flexible and scalable flame spray pyrolysis  

NASA Astrophysics Data System (ADS)

Olivine, LiFePO4 is a promising cathode material for lithium-ion batteries due to its low cost, environmental acceptability and high stability. Its low electric conductivity prevented it for a long time from being used in large-scale applications. Decreasing its particle size along with carbon coating significantly improves electronic conductivity and lithium diffusion. With respect to the controlled formation of very small particles with large specific surface, gas-phase synthesis opens an economic and flexible route towards high-quality battery materials. Amorphous FePO4 was synthesized as precursor material for LiFePO4 by flame spray pyrolysis of a solution of iron acetylacetonate and tributyl phosphate in toluene. The pristine FePO4 with a specific surface from 126-218 m2 g-1 was post-processed to LiFePO4/C composite material via a solid-state reaction using Li2CO3 and glucose. The final olivine LiFePO4/C particles still showed a large specific surface of 24 m2 g-1 and were characterized using X-ray diffraction (XRD), electron microscopy, X-ray photoelectron spectrocopy (XPS) and elemental analysis. Electrochemical investigations of the final LiFePO4/C composites show reversible capacities of more than 145 mAh g-1 (about 115 mAh g-1 with respect to the total coating mass). The material supports high drain rates at 16 C while delivering 40 mAh g-1 and causes excellent cycle stability.

Hamid, N. A.; Wennig, S.; Hardt, S.; Heinzel, A.; Schulz, C.; Wiggers, H.

2012-10-01

156

Numerical modeling of spray combustion with an advanced VOF method  

NASA Technical Reports Server (NTRS)

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.

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

1995-01-01

157

Characterization of the spinel-related oxides Ni x Co 3? x O 4 ( x=0.3,1.3,1.8) prepared by spray pyrolysis at 350 °C  

Microsoft Academic Search

Films of nominal composition NixCo3?xO4 (x=0.3,1.3,1.8) prepared by spray pyrolysis have been characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The results show that the film with x=0.3 is monophasic, presents a spinel-related structure and contains Ni2+, Ni3+, Co2+ and Co3+. In the films with x=1.3 and 1.8 the preparation leads to the formation of significant amounts of

J. F. Marco; J. R. Gancedo; J. Ortiz; J. L. Gautier

2004-01-01

158

Test Method for Boom Suspension Influence on Spray Distribution, Part II: Validation and Use of a Spray Distribution Model  

E-print Network

1 Test Method for Boom Suspension Influence on Spray Distribution, Part II: Validation and Use.lardoux@univ-lehavre.fr 2 UMR « Information et Technologie pour les Agro-bio Procédés », ENSA M., 2 pl. Viala, 34060 behaviour at farm level. The concept is for the sprayer to travel over a bump, to measure boom movements

Paris-Sud XI, Université de

159

Effect of substrate temperature and precursor ratio on properties of thin ZnS films sprayed by improved method  

NASA Astrophysics Data System (ADS)

Zinc sulphide (ZnS) thin films were prepared by improved spray pyrolysis (ISP) method. The ISP parameters, such as carrier gas flow rate, solution flow rate and substrate temperature, were controlled with an accuracy of ±0.25 lpm, ±1 ml/h and ±1 °C, respectively. The solution was sprayed in a pulsed mode. The substrate temperature was optimized by analyzing substrate temperature dependent properties of thin films. The thin film deposited at a temperature of 450 °C was dense and fairly smooth with satisfactory crystallinity and very small impurity content. The effect of precursor ratio in the solution on structural, compositional and optical properties of thin ZnS films, deposited at a temperature of 450 °C, was studied. A gradual increase in band gap energy from 3.524 eV to 3.634 eV, refractive index from 2.5 to 2.9 and dielectric constant from 6.6 to 8.7 were observed with the variation of solution precursor (Zn:S) ratio from (1:2) to (1:6). The structural and compositional studies support this kind of enhancement in optical properties. The results show that the thin ZnS film prepared by ISP at the substrate temperature of 450 °C from a solution with specific precursor ratio can be used for optoelectronic and photovoltaic applications.

Zaware, Rangnath V.; Wagh, Bhiva G.

2014-09-01

160

Understanding the sprayed boric acid method for bulk doping of silicon ribbons  

NASA Astrophysics Data System (ADS)

The sprayed boric acid (SBA) method for bulk doping of silicon ribbons is investigated. Experimental procedures and main results are reviewed. Computational fluid dynamics and experimental tests using partial spraying suggest the role of gas transported evaporated boron oxide to explain the boron incorporation profiles along the sample. The industrial applicability of the SBA method is discussed.

Silva, J. A.; Pêra, David; Brito, Miguel C.; Alves, Jorge Maia; Serra, João; Vallêra, A. M.

2011-07-01

161

Highly durable superhydrophobic coatings with gradient density by movable spray method  

NASA Astrophysics Data System (ADS)

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.

Tenjimbayashi, Mizuki; Shiratori, Seimei

2014-09-01

162

Method and apparatus for heat extraction by controlled spray cooling  

DOEpatents

Two solutions to the problem of cooling a high temperature, high heat flux surface using controlled spray cooling are presented for use on a mandrel. In the first embodiment, spray cooling is used to provide a varying isothermal boundary layer on the side portions of a mandrel by providing that the spray can be moved axially along the mandrel. In the second embodiment, a spray of coolant is directed to the lower temperature surface of the mandrel. By taking advantage of super-Leidenfrost cooling, the temperature of the high temperature surface of the mandrel can be controlled by varying the mass flux rate of coolant droplets. The invention has particular applicability to the field of diamond synthesis using chemical vapor deposition techniques.

Edwards, Christopher Francis (5492 Lenore Ave., Livermore, Alameda County, CA 94550); Meeks, Ellen (304 Daisyfield Dr., Livermore, Alameda County, CA 94550); Kee, Robert (864 Lucille St., Livermore, Alameda County, CA 94550); McCarty, Kevin (304 Daisyfield Dr., Livermore, Alameda County, CA 94550)

1999-01-01

163

10 CFR 431.264 - Uniform test method for the measurement of flow rate for commercial prerinse spray valves.  

Code of Federal Regulations, 2013 CFR

...method for the measurement of flow rate for commercial prerinse spray valves. 431.264 Section...CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Commercial Prerinse Spray Valves Test Procedures...

2013-01-01

164

10 CFR 431.264 - Uniform test method for the measurement of flow rate for commercial prerinse spray valves.  

Code of Federal Regulations, 2012 CFR

...method for the measurement of flow rate for commercial prerinse spray valves. 431.264 Section...CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Commercial Prerinse Spray Valves Test Procedures...

2012-01-01

165

10 CFR 431.264 - Uniform test method for the measurement of flow rate for commercial prerinse spray valves.  

Code of Federal Regulations, 2010 CFR

...method for the measurement of flow rate for commercial prerinse spray valves. 431.264 Section...CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Commercial Prerinse Spray Valves Test Procedures...

2010-01-01

166

10 CFR 431.264 - Uniform test method for the measurement of flow rate for commercial prerinse spray valves.  

...method for the measurement of flow rate for commercial prerinse spray valves. 431.264 Section...CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Commercial Prerinse Spray Valves Test Procedures...

2014-01-01

167

10 CFR 431.264 - Uniform test method for the measurement of flow rate for commercial prerinse spray valves.  

Code of Federal Regulations, 2011 CFR

...method for the measurement of flow rate for commercial prerinse spray valves. 431.264 Section...CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Commercial Prerinse Spray Valves Test Procedures...

2011-01-01

168

Emulsion Combustion and Flame Spray Synthesis of Zinc Oxide\\/Silica Particles  

Microsoft Academic Search

Two flame spray methods, emulsion combustion method (ECM) and flame spray pyrolysis (FSP), were compared for synthesis of pure and mixed SiO2 and ZnO nanoparticles. The effect of silicon precursor was investigated using liquid hexamethyldisiloxane (HMDSO) or SiO2 sol, while for ZnO zinc acetate (ZA) was used. Gas phase reaction took place when using HMDSO as Si precursor, forming nanoparticles,

Takao Tani; Naoyoshi Watanabe; Kazumasa Takatori

2003-01-01

169

Facile Water-based Spray Pyrolysis of Earth-Abundant Cu2FeSnS4 Thin Films as an Efficient Counter Electrode in Dye-Sensitized Solar Cells.  

PubMed

A novel approach to produce earth-abundant Cu2FeSnS4 (CFTS) thin film using spray pyrolysis of nontoxic aqueous precursors followed by sulfurization is reported. The CFTS phase formation was confirmed by both Raman spectroscopy and X-ray diffraction techniques. Hall measurements of these films reveal p-type conductivity with good charge carrier density and mobilities appropriate for solar harvesting devices. To the best of our knowledge, this is the first report on the electrical properties of solution-processed Cu2FeSnS4 thin films estimated using Hall measurements. Dye-sensitized solar cells (DSSC) fabricated with CFTS thin film as a photocathode in iodine/iodide electrolyte exhibit good power conversion efficiency, 8.03%, indicating that CFTS would be a promising cheaper alternative to replace Pt as a counter electrode in DSSCs. PMID:25255739

Prabhakar, Rajiv Ramanujam; Huu Loc, Nguyen; Kumar, Mulmudi Hemant; Boix, Pablo P; Juan, Sun; John, Rohit Abraham; Batabyal, Sudip K; Wong, Lydia Helena

2014-10-22

170

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

SciTech Connect

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.

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

1995-12-31

171

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

DOEpatents

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.

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

1997-09-02

172

Optimization of Jatropha Oil Extraction and Its By-Product Utilization by Pyrolysis Method  

E-print Network

as found in a savanna or desert region (Carels, 2009). The trees shed the leaves in dry season and blossom in wet season. Two flowering peaks often appear during summer and autumn. It will take approximately 3 ? 4 months after blooming to seed maturity..., olive, sunflower, rapeseed and Jatropha were first extracted by a mechanic press. The de-oiled cakes were then used to perform a pyrolysis process at a pyrolysis temperature in the range of 450 ? 550 oC with the liquid product yield about 40 ? 60 wt...

Kongkasawan, Jinjuta 1987-

2012-08-20

173

Method of high heat flux removal by usage of liquid spray cooling  

NASA Astrophysics Data System (ADS)

High heat flux removal are important issue in many perspective applications such as computer chips, laser diode arrays, or boilers working on supercritical parameters. Electronic microchips constructed nowadays are model example of high heat flux removal, where the cooling system have to maintain the temperature below 358 K and take heat flux up to 300 W/cm2. One of the most efficient methods of microchips cooling turns out to be the spray cooling method. Review of installations has been accomplished for removal at high heat flux with liquid sprays. In the article are shown high flux removal characteristic and dependences, boiling critical parameters, as also the numerical method of spray cooling analysis.

Smakulski, Przemys?aw

2013-09-01

174

Confined-pyrolysis as an experimental method for hydrothermal organic synthesis  

NASA Astrophysics Data System (ADS)

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 compounds 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.

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

1995-10-01

175

Confined-Pyrolysis as an Experimental Method for Hydrothermal Organic Synthesis  

NASA Technical Reports Server (NTRS)

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.

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

1995-01-01

176

Method for the gasification of carbonaceous matter by plasma arc pyrolysis  

SciTech Connect

Apparatus and method for gasification of carbonaceous matter by plasma arc pyrolysis are disclosed. In one embodiment, a refractory-lined furnace is provided with a depression along its base for holding a pool of molten metal which acts as the external electrode for a bank of long arc column plasma torches which provide a heat mass for the process. The plasma arc pressure imparts momentum to the surface of the melt and causes it to flow in cusping eddy currents during the process. Crushed coal is deposited through the roof of the furnace by a rotary feeder in continuous plural streams. The coal is devolatilized in a matter of milli seconds, and the volatiles are cracked as the coal falls by gravity through the interior of the furnace. The remaining carbon-rich char collects at plural sites on the surface of the melt, and the mounds of char are rotated by the eddy currents. Steam is continuously injected into the furnace to produce hydrocarbon gases through reaction with the carbon-rich char. A residence time of 5 to 30 min produces carbon utilization of up to 92%. The hot raw gases are directed through a gas cooler where heat is extracted for producing the process steam, and the cooled raw gases are upgraded to pipeline quality by conventional CO/sub 2/ and moisture removal techniques and by methanization with catalysts. The raw gas may also be burned directly as a medium-Btu gas or used as a reductant in the direct reduction of iron ore.

Camacho, S.L.

1980-01-01

177

Complementary analytical liquid chromatography methods for the characterization of aqueous phase from pyrolysis of lignocellulosic biomasses.  

PubMed

In this work, two analytical liquid chromatography methods were developed and compared for the characterization of aqueous phases from pyrolysis of lignocellulosic biomasses. NanoLC electron ionization-mass spectrometry (EI-MS) represents a novel and useful tool for both separation and identification of semi/nonvolatile and thermolabile molecules. The use of nanoscale flow rates, the highly reproducibility, and high detailed information on EI spectra are the principal advantages of this technique. On the other hand, comprehensive 2D-LC, providing a two-dimensional separation, increases the overall peak capacity lowering the occurrence of peak coelutions. Despite the use of reversed phase modes in both dimensions, a satisfactory degree of orthogonality was achieved by the employment of a smart design of gradient elution strategies in the second dimension in combination with photodiode array detection (PDA) and atmospheric pressure chemical ionization-mass spectrometry (APCI-MS). Because of the absence of the preliminary extraction procedure, the fingerprint obtained for these samples results is independent of the extraction yield or contamination contrary to the gas chromatography-mass spectrometry (GC-MS) approach where a liquid-liquid extraction of the water phase is necessary. The main classes of identified compounds were phenols, ketones, furans, and alcohols. The synergistic information on the two powerful analytical approaches, e.g., NanoLC EI-MS and LC × LC, in the identification of such complex samples has never been investigated and fully benefit on the one hand from the superior degree of mass spectral information from EI-MS and on the other hand from enhanced LC × LC compound separation. PMID:25327521

Tomasini, Débora; Cacciola, Francesco; Rigano, Francesca; Sciarrone, Danilo; Donato, Paola; Beccaria, Marco; Caramão, Elina B; Dugo, Paola; Mondello, Luigi

2014-11-18

178

Estimation of thermal cracking stress during spraying of thermal barrier coatings by laser AE method  

NASA Astrophysics Data System (ADS)

Thermal barrier coatings (TBCs) system is deposited by plasma spray method usually contain a number of cracks. These cracks can be classified into vertical and horizontal cracks and certainly affect the performance of TBCs. A monitoring method to detect the crack generation and propagation during plasma spraying is significantly required. In this study, a laser AE technique which enables in-situ and non-contact monitoring during spring process was developed to study the cracking phenomena in TBC. A new scanning pattern of the plasma torch was successfully applied to introduce only vertical cracks into the top coat. More number of AE events could be obtained by applying an improved noise filtering and multiple-threshold event detection procedures. A temperature history during spraying was also measured and used for thermal stress simulation by FEM analyses. A relationship between cracking and thermal stress in the top coat was established based on the results of AE monitoring and FEM simulation.

Ito, Kaita; Kuriki, Hitoshi; Araki, Hiroshi; Kuroda, Seiji; Enoki, Manabu

2014-02-01

179

Waste pyrolysis - Alternative fuel source  

Microsoft Academic Search

Four means for producing alternative fuel sources via waste pyrolysis are considered. In the first, low-Btu gas is produced by waste pyrolysis in a refractory-lined rotary kiln. The second is based on solid waste passing through a gasifier, and then through stages of drying, pyrolysis, and combustion. This also yields a low-Btu gas. The third method produces a medium-Btu gas

L. M. Pruce

1978-01-01

180

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

NASA Astrophysics Data System (ADS)

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 and interactions of the droplet impact craters are tracked versus time within the limitations of the current model. A comparison of results from this code to experimental results shows similar trends in surface behavior and heat transfer values. Three methods have been used to directly compare the simulation results with published experimental data, including: contact line length estimates, empirical heat transfer equation calculations, and non-dimensional Nusselt numbers. A Nusselt number of 55.5 was calculated for experimental values, while a Nu of 16.0 was calculated from the simulation.

Kreitzer, Paul Joseph

181

Influence of Al, In, Cu, Fe and Sn dopants in the microstructure of zinc oxide thin films obtained by spray pyrolysis  

Microsoft Academic Search

A spray pyrolytic system was used to obtain ZnO:X films doped with different elements, X=Al, In, Cu, Fe and Sn. A 0.1 M solution of zinc acetate in a mixture of ethanol and deionised water, in a volume proportion of 3:1, was employed. Dopant sources were aluminium chloride, indium acetate, copper acetate, iron chloride and tin tetrachloride. The atomic percentage

J. Morales; W. Estrada L; E. Andrade; M. Miki-Yoshida

2000-01-01

182

Spray atomization and combustion  

NASA Technical Reports Server (NTRS)

New theoretical and experimental methods for studying sprays are reviewed. Common methods to analyze dilute sprays are described and used to interpret recent measurements of the structure of dilute sprays and related dispersed turbulent jets. Particle-laden jets, nonevaporating, evaporating, and combusting sprays, and noncondensing and condensing bubbly jets are examined and used to initially evaluate current analytical methods for a wide range of conditions. Dense sprays are briefly discussed.

Faeth, G. M.

1986-01-01

183

Pyrolysis rates of biomass materials  

Microsoft Academic Search

A method is proposed by which pyrolysis rates of biomass materials can be predicted from the species compositions in terms of the basic constituents (cellulose, hemicellulose and lignin) and their individual kinetic parameters. The activation energies, frequency factors and reaction orders for cellulose, hemicellulose and lignin have been determined in a conventional manner. The measured rates of pyrolysis of different

T. Rajeswara Rao; Atul Sharma

1998-01-01

184

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)

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 2?-scans, rocking curves (?-scans), and pole figure measurements. MgO was found to have a very weak in-plane texture.

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

2010-09-01

185

Spray coating as a simple method to prepare catalyst for growth of diameter-tunable single-walled carbon nanotubes  

E-print Network

by alcohol #12;catalytic chemical vapor deposition (ACCVD),[7] and the nanotube diameter can be modulated by modifying the deposition recipe. Figures 1a and b present schematics of spray coating and our conventionalSpray coating as a simple method to prepare catalyst for growth of diameter-tunable single

Maruyama, Shigeo

186

Temperature Effects on Cu2ZnSnS4 (CZTS) Films Deposited by Spraying Method  

Microsoft Academic Search

CZTS containing ink was prepared by a sonochemical method, and properties of CZTS thin films deposited by a spraying method were investigated. We used CuCl2, ZnCl, SnCl2 and thiourea as precursor materials, 2-methoxyethanol as a solvent, and monoethanolamine as a stabilizer. X-ray diffraction (XRD) patterns from the CZTS films mainly exhibited the (112), (200), (220), and (312) planes of a

Hong Tak Kim; Donghwan Kim

2012-01-01

187

Effect of Al-doped on physical properties of ZnO Thin films grown by spray pyrolysis on SnO2: F/glass  

NASA Astrophysics Data System (ADS)

Transparent conducting thin films of aluminum-doped zinc oxide (ZnO:Al) have been deposited on SnO2:F/glass by the chemical spray technique, starting from zinc acetate (CH3CO2)2Zn.2H2O and aluminum chloride AlCl3. The effect of changing the aluminum-to-zinc ratio y from 0 to 3 at.%, has been thoroughly investigated. It was found that the optical and electrical properties of Al doped ZnO films improved with the addition of aluminum in the spray solution until y=2%. At this Al doping percentage, the thin layers have a resistivity equal to 4.1 × 10-4 ?.cm and a transmittance of about 90 % in the region [600-1000] nm. XRD patterns confirm that the films have polycristalline nature and a wurtzite (hexagonal) structure which characterized with (100), (002) and (101) principal orientations. The undoped films have (002) as the preferred orientation but Al doped ones have (101) as the preferred orientation. Beyond y= 1%, peak intensities decrease considerably.

Ajili, M.; Jebbari, N.; Kamoun Turki, N.; Castagné, M.

2012-06-01

188

Fluidized coal pyrolysis apparatus  

Microsoft Academic Search

Method and apparatus are claimed for pyrolyzing agglomerative coals. The method comprises introducing a fluidized bed of hot char particles into a pyrolysis chamber or reactor, and injecting upwardly into the chamber a high velocity jet of agglomerative coal particles in a carrier gas, the fluidized hot char particles surrounding the high velocity coal jet and heating the coal particles

1982-01-01

189

High temperature fatigue deformation behaviors of thermally sprayed steel measured with electronic speckle pattern interferometry method  

SciTech Connect

High temperature fatigue (R=0) damage and deformation behaviors of SUS304 steel thermally sprayed with Al{sub 2}O{sub 3}/NiCr coating were investigated using an electronic speckle pattern interferometry (ESPI) method. Surface cracks and delamination occurred after 1x10{sup 5} cycles test when {sigma}{sub max} was 202 MPa at 873 K. The lengths and number of cracks and delamination largely decreased when {sigma}{sub max} or temperature decreased to 115 MPa or 573 K, respectively. Strain values along cracks measured with the ESPI method were much larger than other areas due to crack opening under the tensile load. The positions of strain concentration zones on strain distribution figures by ESPI method were well corresponded to those of cracks on sprayed coatings. Strain values decreased largely where local delamination occurred.

Wang, Rongguang; Kido, Mitsuo

2003-07-14

190

Coal pyrolysis process  

Microsoft Academic Search

Method and apparatus for pyrolyzing agglomerative coals which comprises introducing a fluidized bed of hot char particles into a pyrolysis chamber or reactor, and injecting upwardly into the chamber a high velocity jet of agglomerative coal particles in a carrier gas, the fluidized hot char particles surrounding the high velocity coal jet and heating the coal particles to yield gaseous

1981-01-01

191

Numerical Modeling of Spray Combustion with an Unstructured-Grid Method  

NASA Technical Reports Server (NTRS)

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.

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

1996-01-01

192

Study of surface cleaning methods and pyrolysis temperatures on nanostructured carbon films using x-ray photoelectron spectroscopy  

SciTech Connect

Nanostructured carbon (ns-C) films fabricated by stabilization and pyrolysis of diblock copolymers are of interest for a variety of electrical/electronic applications due to their chemical inertness, high-temperature insensitivity, very high surface area, and tunable electrical resistivity over a wide range [Kulkarni et al., Synth. Met. 159, 177 (2009)]. Because of their high porosity and associated high specific surface area, controlled surface cleaning studies are important for fabricating electronic devices from these films. In this study, quantification of surface composition and surface cleaning studies on ns-C films synthesized by carbonization of diblock copolymers of polyacrylonitrile-b-poly(n-butyl acrylate) at two different temperatures were carried out. X-ray photoelectron spectroscopy was used for elemental analysis and to determine the efficacy of various surface cleaning methods for ns-C films and to examine the polymer residues in the films. The in-situ surface cleaning methods included HF vapor treatment, vacuum annealing, and exposure to UV-ozone. Quantitative analysis of high-resolution XPS scans showed 11 at. % nitrogen was present in the films pyrolyzed at 600 Degree-Sign C, suggesting incomplete denitrogenation of the copolymer films. The nitrogen atomic concentration decreased significantly for films pyrolyzed at 900 Degree-Sign C confirming extensive denitrogenation at that temperature. Furthermore, quantitative analysis of nitrogen subpeaks indicated higher loss of nitrogen atoms residing at the edge of graphitic clusters relative to that of nitrogen atoms within the graphitic clusters, suggesting higher graphitization with increasing pyrolysis temperature. Of the surface cleaning methods investigated, in-situ annealing of the films at 300 Degree-Sign C for 40 min was found to be the most efficacious in removing adventitious carbon and oxygen impurities from the surface.

Kerber, Pranita; Porter, Lisa M.; McCullough, Lynne A.; Kowalewski, Tomasz; Engelhard, Mark; Baer, Donald [Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213 (United States); Chemistry Department, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213 (United States); Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States)

2012-11-15

193

Method for the assessment of airborne off-target pesticide spray concentrations due to aircraft wing-tip vortex  

E-print Network

The purpose of this thesis is to develop a method for assessing airborne concentrations caused by off-target pesticide drift. Concentrations are bounded by the worst credible circumstances within a normal aircraft pesticide spraying. It is assumed...

Oliva, Sergio Eduardo

2012-06-07

194

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

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%.

Hong, Young Jun; Choi, Seung Ho; Sim, Chul Min; Lee, Jung-Kul [Department of Chemical Engineering, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul 143-701 (Korea, Republic of)] [Department of Chemical Engineering, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul 143-701 (Korea, Republic of); Kang, Yun Chan, E-mail: yckang@konkuk.ac.kr [Department of Chemical Engineering, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul 143-701 (Korea, Republic of)

2012-12-15

195

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

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. PMID:22945152

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

2012-09-01

196

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

NASA Technical Reports Server (NTRS)

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.

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

1991-01-01

197

A method to determine liquid concentration in non-stationary axisymmetric sprays  

NASA Astrophysics Data System (ADS)

A method to determine liquid concentration in non-stationary axisymmetric sprays of high density and velocity is described in this paper. In this method a Phase Doppler Anemometer (PDA) is used together with a light extinction technique based on a CCD camera. Image acquisitions and PDA measurements are taken at the same time from injection start during a very short temporal window. The data obtained with both techniques are processed independently and then combined to obtain the local liquid concentration and number of droplets per unit volume. In addition, the volumetric flux of liquid can be calculated because the droplet velocities are known.

Tinaut, F. V.; Melgar, A.; Castro, F.; Sánchez, M. L.; Giménez, B.

198

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

PubMed

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. PMID:19686825

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

2009-12-01

199

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

PubMed Central

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

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

2013-01-01

200

Nondestructive Evaluation of Thermal Spray Coating INterface Quality by Eddy Current Method.  

National Technical Information Service (NTIS)

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 characteri...

B. Mi G. Zhao, R. Bayles

2006-01-01

201

Acoustic microscopy of functionally graded thermal sprayed coatings using stiffness matrix method and Stroh formalism  

NASA Astrophysics Data System (ADS)

Acoustic microscopy of multilayered media as well as functionally graded coatings on substrate necessitates to model acoustic wave propagation in such materials. In particular, we chose to use Stroh formalism and the recursive stiffness matrix method to obtain the reflection coefficient of acoustic waves on these systems because this allows us to address the numerical instability of the conventional transfer matrix method. In addition, remarkable simplification and computational efficiency are obtained. We proposed a modified formulation of the angular spectrum of the transducer based on the theoretical analysis of a line-focus transducer for broadband acoustic microscopy. A thermally sprayed coating on substrate is treated as a functionally graded material along the depth of the coating and is approximately represented by a number of homogeneous elastic layers with exponentially graded elastic properties. The agreement between our experimental and numerical analyses on such thermal sprayed coatings with different thicknesses confirms the efficiency of the method. We proved the ability of the inversion procedure to independently determine both thickness and gradient of elastic properties. The perspective of this work is the opportunity to non-destructively measure these features in functionally graded materials.

Deng, X. D.; Monnier, T.; Guy, P.; Courbon, J.

2013-06-01

202

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

PubMed Central

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 (? = 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

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

2012-01-01

203

Sprays and Spraying  

E-print Network

35 Stock Dips ............................................. 35 ................................ Directions for Sending Insects 36 SPRAYS AND SPRAYING. BY F. :B. B. S. E., ENTOJIOLOGIST IN CHARGE; STATE EK-TOBIOT~O(:IST. INTRODUCTION.... This material ~hould never be used as a spray to put on plants, since it severely burns all tissue that it comes in contact with. The only place it can be ssfely used is in making poisoned baits for grasshopper4 and cutworms. It is the cheapest form of poison...

Paddock, F.B. (Floyd B.)

1916-01-01

204

An analytical method of non-gray three-dimensional radiation heat transfer in spray combustion  

NASA Astrophysics Data System (ADS)

The analytical basis of the numerical simulation method employed in the authors' recent investigations of radiative heat transfer in spray combustion (Chang and Rhee, 1983 and 1984; Rhee and Chang, 1985; Chang et al., 1985) is explained, and some typical results are summarized and illustrated with graphs. The method is applicable to problems where the species are distributed normally or exponentially in a cylindrical coordinate system. The procedure is shown to permit analytical solutions for optically thick or thin media and to facilitate numerical solutions for medially optically thick/thin media. Results presented concern radiation incident on or transmitted through the cylinder head of a direct-injection diesel engine and the heat-transfer contribution of soot and gaseous species and their combustion.

Chang, S. L.; Rhee, K. T.

1986-12-01

205

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

NASA Astrophysics Data System (ADS)

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, 2? 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 quality gate was also reduced from 0.35 WDPV to 0.10 WDPV. This reveals that the objective of this research is met and this procedure can be used as quality improvement guidance for paint shop of automotive vehicle.

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

2010-10-01

206

Determination of absolute coccolith abundances in deep-sea sediments by spiking with microbeads and spraying (SMS-method)  

Microsoft Academic Search

A quick new method is described for the quantification of absolute nannofossil proportions in deep-sea sediments. This method (SMS) is the combination of Spiking a sample with Microbeads and Spraying it on a cover slide. It is suitable for scanning electron microscope (SEM) analyses and for light microscope (LM) analyses. Repeated preparation and counting of the same sample (30 times)

Jörg Bollmann; Bernhard Brabec; Mara Y Cortés; Markus Geisen

1999-01-01

207

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

DOEpatents

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.

Besser, Matthew F. (Urbandale, IA); Terpstra, Robert L. (Ames, IA); Sordelet, Daniel J. (Ames, IA); Anderson, Iver E. (Ames, IA)

2002-03-19

208

A microbiologic investigation following the disinfection of irreversible hydrocolloid materials using the spray method.  

PubMed

Antimicrobial efficacy of three spray disinfectants--0.525 percent sodium hypochlorite (bleach), deconex and Sanosil--was evaluated on contaminated alginate disks. Disks were sprayed eight to 10 times after rinsing in water for 15 seconds. The samples were then placed into plastic bags containing a sterile moist cotton roll for 10 minutes. The use of 0.525 percent sodium hypochlorite sprayed onto the surface of alginate effectively disinfected 96.6 percent of the samples. PMID:19653403

Ghahramanloo, Ahmad; Sadeghian, Ali; Sohrabi, Keyvan; Bidi, Ali

2009-07-01

209

A pyrolysis/gas chromatographic method for the determination of hydrogen in solid samples.  

PubMed

A method is described for the determination of hydrogen in solid samples. The sample is heated under vacuum after which the evolved gases are separated by gas chromatography with a helium ionization detector. The system is calibrated by injecting known amounts of hydrogen, as determined manometrically. The method, which is rapid and reliable, was checked for a variety of lunar soils; the limit of detection is about 10 ng of hydrogen. PMID:11542122

Carr, R H; Bustin, R; Gibson, E K

1987-01-01

210

A pyrolysis/gas chromatographic method for the determination of hydrogen in solid samples  

NASA Technical Reports Server (NTRS)

A method is described for the determination of hydrogen in solid samples. The sample is heated under vacuum after which the evolved gases are separated by gas chromatography with a helium ionization detector. The system is calibrated by injecting known amounts of hydrogen, as determined manometrically. The method, which is rapid and reliable, was checked for a variety of lunar soils; the limit of detection is about 10 ng of hydrogen.

Carr, R. H.; Bustin, R.; Gibson, E. K.

1987-01-01

211

Catalytic pyrolysis of biomass for biofuels production  

Microsoft Academic Search

Fast pyrolysis bio-oils currently produced in demonstration and semi-commercial plants have potential as a fuel for stationary power production using boilers or turbines but they require significant modification to become an acceptable transportation fuel. Catalytic upgrading of pyrolysis vapors using zeolites is a potentially promising method for removing oxygen from organic compounds and converting them to hydrocarbons. This work evaluated

Richard French; Stefan Czernik

2010-01-01

212

Toxicity of pyrolysis gases from polyether sulfone  

NASA Technical Reports Server (NTRS)

A sample of polyether sulfone was evaluated for toxicity of pyrolysis gases, using the toxicity screening test method developed at the University of San Francisco. Animal response times were relatively short at pyrolysis temperatures of 600 to 800 C, with death occurring within 6 min. The principal toxicant appeared to be a compound other than carbon monoxide.

Hilado, C. J.; Olcomendy, E. M.

1979-01-01

213

Toxicity of pyrolysis gases from polyoxymethylene  

NASA Technical Reports Server (NTRS)

A sample of polyoxymethylene was evaluated for toxicity of pyrolysis gases, using the toxicity screening test method developed at the University of San Francisco. Under several test conditions, this material gave shorter times to death than many other synthetic polymers. Carbon monoxide appeared to be the principal toxicant in the pyrolysis gases.

Hilado, C. J.; Schneider, J. E.; Brauer, D. P.

1979-01-01

214

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

Microsoft Academic Search

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

M. J. McIntosh; G. G. Arzoumanidis

1995-01-01

215

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

Microsoft Academic Search

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

Michael J. McIntosh; Gregory G. Arzoumanidis

1997-01-01

216

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

Microsoft Academic Search

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

M. J. McIntosh; G. G. Arzoumanidis

1997-01-01

217

Evaluation of char fuel ratio in municipal pyrolysis waste  

Microsoft Academic Search

A simple method to estimate the fuel ratio (=(Fixed carbon)\\/(volatile matter)) as a combustion index of char obtained from the pyrolysis of municipal waste (MW) by a waste disposal facility was developed, based on the data for the pyrolysis of cellulose (CE), polyethylene (PE), polypropylene (PP), polystyrene (PS) and poly(vinyl chloride) (PVC). Pyrolysis reactions involved were explained by thermal analysis.

Yoshiaki Matsuzawa; Muneo Ayabe; Junya Nishino; Nobuhiko Kubota; Mikio Motegi

2004-01-01

218

Application of multi-breakage coagulation methods for droplet size distributions in spray injection-combustion  

Microsoft Academic Search

A multibreakage, coagulation model for droplet interfacial dynamics in spray injection-combustion is developed that has potential application in combustor analysis for liquid fueled liquid oxidizer rocket and other propulsion engines. The model is developed from basic principles of droplet interfacial dynamics and population balance starting from what is popularly known as the spray equation on the particle\\/droplet analogue of the

N. Nagaraj; C. K. Lombard

1986-01-01

219

Method for the recovery of clean pyrolysis off-gas and a rotary recycling means therefor  

Microsoft Academic Search

A method and apparatus for stripping entrained organic vapor and solid particulate matter from a pyrolytic off-gas stream is disclosed. The off-gas is introduced at the top of a conical chamber having a variable speed ''squirrel cage'' rotor at its top. The wet, dirty, off-gas is drawn into the rotor from below and impinged upon the chamber walls which causes

L. W. Elston; D. R. Hurst

1981-01-01

220

Fabrication and analysis of PMMA, ABS, PS, and PC superhydrophobic surfaces using the spray method  

NASA Astrophysics Data System (ADS)

In this study, superhydrophobic surfaces were fabricated using a facile spraying technique with poly(methyl methacrylate) (PMMA), acrylonitrile butadiene styrene (ABS), polystyrene (PS) and polycarbonate (PC). Also, the surface energy was qualitatively analyzed via the water contact angle with respect to the spraying time and the sprayed position. Firstly, PMMA, ABS, PS and PC were dissolved by using solvents such as methyl chloride, methanol, THF (tetrahydrofuran), and methanol, respectively. After that, the dissolved polymer was sprayed onto a thin film of the same polymer for various spraying times. Nozzle size, pressure and spraying distance were fixed as 0.2 mm, 0.1 bar, and 100 mm, respectively, after several feasibility experiments. For the sprayed surfaces, the topology was analyzed with scanning electron microscopy (SEM) and confocal microscopy, and the surface energy was qualitatively analyzed using the water-contactangle measurement. According to a quantitative analysis using the roughness factor and he Wenzel equation, all specimens could be assumed to be in a Wenzel state. To convert the Wenzel state into a Cassie-Baxster state by decreasing the surface energy of polymer-sprayed specimen, we treated the polymer-sprayed surfaces by using trichloro (1H, 1H, 2H, 2H-perfluorooctyl) silane. Consequently, non-sticky superhydrophobic surfaces having water contact angles greater than 155° and water sliding angles lower than 8° were fabricated. The water contact angle and the water sliding angle were measured by using a contact-angle-measuring device. In addition, a brief qualitative analysis of the effect of surface topology on the water sliding angle was conducted for the polymer-sprayed specimens.

Cho, Young-Sam; Ahn, Sang Hyun; Lee, Se-Hwan

2013-07-01

221

Characterization of polycyclic aromatic hydrocarbons (PAHs) on lime spray dryer (LSD) ash using different extraction methods.  

PubMed

In this study, traditional Soxhlet, automatic Soxhlet and ultrasonic extraction techniques were employed to determine the speciation and concentration of polycyclic aromatic hydrocarbons (PAHs) on lime spray dryer (LSD) ash samples collected from the baghouse of a spreader stoker boiler. To test the efficiencies of different extraction methods, LSD ash samples were doped with a mixture of 16 US EPA specified PAHs to measure the matrix spike recoveries. The results showed that the spike recoveries of PAHs were different using these three extraction methods with dichloromethane (DCM) as the solvent. Traditional Soxhlet extraction achieved slightly higher recoveries than automatic Soxhlet and ultrasonic extraction. Different solvents including toluene, DCM:acetone (1:1 V/V) and hexane:acetone (1:1 V/V) were further examined to optimize the recovery using ultrasonic extraction. Toluene achieved the highest spike recoveries of PAHs at a spike level of 10 microg kg(-1). When the spike level was increased to 50 microg kg(-1), the spike recoveries of PAHs also correspondingly increased. Although the type and concentration of PAHs detected on LSD ash samples by different extraction methods varied, the concentration of each detected PAH was consistently low, at microg kg(-1) levels. PMID:15990154

Sun, Ping; Weavers, Linda K; Taerakul, Panuwat; Walker, Harold W

2006-01-01

222

Comparison of Isolated Indentation and Grid Indentation Methods for HVOF Sprayed Cermets  

NASA Astrophysics Data System (ADS)

This paper compares the results of two approaches of instrumented indentation for characterization of mechanical properties of HVOF coatings. Three types of HVOF sprayed coatings (Cr3C2-NiCr, WC-Co, (Ti, Mo)(C,N)-NiCo) were investigated by the means of isolated nanoindentation and grid indentation methods. The results of the isolated indentation revealed hardness and elastic modulus of the individual phases in very good agreement with the corresponding bulk material. The grid indentation method, based on statistical evaluation of a large number of indentations, was influenced by the carbide-matrix interface, which gave rise to a third peak apart from the two peaks corresponding to the carbides and metallic matrix. As a consequence, the bimodal Gaussian fit was insufficient and a trimodal fit had to be used. The results extracted from low load grid nanoindentations were quite close to the results of isolated indentations whereas higher load grid nanoindentation revealed overall properties of the coating.

Nohava, Ji?í; Haušild, Petr; Houdková, Šárka; Enžl, Radek

2012-06-01

223

Friability of spray-applied fireproofing and thermal insulations: the basis for a field-test method  

Microsoft Academic Search

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

W. J. Rossiter; W. E. Roberts; R. G. Mathey

1987-01-01

224

Miniature spray-painting booth  

NASA Technical Reports Server (NTRS)

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.

Fee, K. W.

1970-01-01

225

Method and closing pores in a thermally sprayed doped lanthanum chromite interconnection layer  

DOEpatents

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.

Singh, P.; Ruka, R.J.

1995-02-14

226

Method and closing pores in a thermally sprayed doped lanthanum chromite interconnection layer  

DOEpatents

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.

Singh, Prabhakar (Export, PA); Ruka, Roswell J. (Pittsburgh, PA)

1995-01-01

227

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)

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.

Shakkottai, Parthasarathy (Inventor); Kwack, Eug Y. (Inventor); Lawson, Daniel D. (Inventor)

1991-01-01

228

Non-Destructive Evaluation of Thermal Spray Coating Interface Quality By Eddy Current Method  

SciTech Connect

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.

B. Mi; G. Zhao; R. Bayles

2006-08-10

229

Kinetics study on conventional and microwave pyrolysis of moso bamboo.  

PubMed

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 84.22kJ/mol with the heating rate decreasing from 135 to 60°C/min during conventional pyrolysis. The value of activation energy was 24.5kJ/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. PMID:25194260

Dong, Qing; Xiong, Yuanquan

2014-11-01

230

On Spray Pyrolyzed Nickel Oxide Thin Films  

Microsoft Academic Search

Nickel oxide thin films have been prepared by a simple and inexpensive spray pyrolysis technique and have been studied for their structural, optical and electrical properties. The films consist of NiO (cubic) phase. The direct band gap energy is estimated to be 3.4 eV. Room temperature electrical resistivity is of the order of 106 W-cm.

L. D. Kadam; C. H. Bhosale; P. S. Patil

1997-01-01

231

Carbon nanoscrolls by pyrolysis of a polymer  

NASA Astrophysics Data System (ADS)

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.

Yadav, Prasad; Warule, Sambhaji; Jog, Jyoti; Ogale, Satishchandra

2012-12-01

232

Hybrid Turbulence Modeling of Liquid Spray Impingement on a Heated Wall with Arbitrary Lagrangian Eulerian Method  

Microsoft Academic Search

Numerical simulation of two phase spray impingement on a heated wall was carried out. Hybrid turbulence modeling was used for analysis where large eddy simulation was employed away from the wall, and a k-epsilon model was employed near the wall. The effect of vortex motion on turbulent heat flux values was analyzed using different Reynolds numbers of impingement and at

S. Kondaraju; J. S. Lee

2007-01-01

233

APPLICATION OF A SPRAY DEPOSITION METHOD FOR REVERSED PHASE LIQUID CHROMATOGRAPHY-MASS SPECTROMETRY  

EPA Science Inventory

Four coal gasification wastewater samples were analyzed for nonvolatile and polar organics by liquid chromatography-mass spectrometry (LC/MS). Samples were separated on a reverse phase liquid chromatographic column using an aqueous solvent as the eluant. A special spray depositio...

234

High order moment method for polydisperse evaporating sprays with mesh movement: application to internal combustion engines  

E-print Network

to internal combustion engines D. Kaha,3 , O. Emreb,c,d,2 , Q. H. Trand , S. de Chaisemartind, , S. Jayd , F meshes. Extending the approach to internal combustion engine and fuel injection requires solving two simulations with spray in internal combustion engines have become a critical target in the automotive industry

Paris-Sud XI, Université de

235

Method for thermally spraying crack-free mullite coatings on ceramic-based substrates  

NASA Technical Reports Server (NTRS)

A process for depositing a mullite coating on a silicon-based material, such as those used to form articles exposed to high temperatures and including the hostile thermal environment of a gas turbine engine. The process is generally to thermally spray a mullite powder to form a mullite layer on a substrate, in which the thermal spraying process is performed so that the mullite powder absorbs a sufficient low level of energy from the thermal source to prevent evaporation of silica from the mullite powder. Processing includes deposition parameter adjustments or annealing to maintain or reestablish phase equilibrium in the mullite layer, so that through-thickness cracks in the mullite layer are avoided.

Spitsberg, Irene T. (Inventor); Wang, Hongyu (Inventor); Heidorn, Raymond W. (Inventor)

2000-01-01

236

Method for thermally spraying crack-free mullite coatings on ceramic-based substrates  

NASA Technical Reports Server (NTRS)

A process for depositing a mullite coating on a silicon-based material, such as those used to form articles exposed to high temperatures and including the hostile thermal environment of a gas turbine engine. The process is generally to thermally spray a mullite powder to form a mullite layer on a substrate, in which the thermal spraying process is performed so that the mullite powder absorbs a sufficient low level of energy from the thermal source to prevent evaporation of silica from the mullite powder. Processing includes deposition parameter adjustments or annealing to maintain or reestablish phase equilibrium in the mullite layer, so that through-thickness cracks in the mullite layer are avoided.

Spitsberg, Irene T. (Inventor); Wang, Hongyu (Inventor); Heidorn, Raymond W. (Inventor)

2001-01-01

237

Pyrolysis system evaluation study  

NASA Technical Reports Server (NTRS)

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.

1974-01-01

238

Fentanyl pectin nasal spray: a novel intranasal delivery method for the treatment of breakthrough cancer pain.  

PubMed

Fentanyl pectin nasal spray is a novel intranasal formulation for the management of breakthrough cancer pain in patients taking and tolerant to opioids for persistent cancer pain. The pectin-based delivery modulates the product's transmucosal absorption. Nasal delivery allows fentanyl pectin nasal spray to achieve a greater maximum plasma concentration than oral transmucosal fentanyl products and at a much faster rate. Compared with intranasal fentanyl compounded with aqueous solutions, the pectin-based system decreases the maximum plasma concentration and prolongs exposure to more closely match the time course of a typical breakthrough cancer pain episode. Throughout all phases of clinical studies, it was shown to be safe and effective in doses between 100 and 800 µg per breakthrough pain episode. Fentanyl pectin nasal spray is the only proprietary intranasal fentanyl formulation in the USA and one of two in Europe. Owing to the medication's delivery system, the pharmacokinetics and subsequent dosing are unique to this product and should not be interchanged with any other proprietary or compounded fentanyl product. PMID:23272789

Bulloch, Marilyn N; Hutchison, Amber M

2013-01-01

239

Non-Destructive Evaluation of Thermal Spray Coating Interface Quality by Eddy Current Method  

SciTech Connect

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.

B.Mi; X. Zhao; R. Bayles

2006-05-26

240

Small-scale hydrous pyrolysis of macromolecular material in meteorites  

NASA Astrophysics Data System (ADS)

The hydrous pyrolysis method, usually performed on several hundred grams of terrestrial rock sample, has been scaled down to accommodate less than two grams of meteorite sample. This technique makes full use of the high yields associated with hydrous pyrolysis experiments and permits the investigation of the meteorite macromolecular material, the major organic component in carbonaceous meteorites. The hydrous pyrolysis procedure transforms the high molecular weight macromolecular material into low molecular weight fragments. The released entities can then be extracted with supercritical fluid extraction. In contrast to the parent structure, the pyrolysis products are amenable for analysis by gas chromatography-based techniques. When subjected to hydrous pyrolysis, two carbonaceous chondrites (Orgueil and Cold Bokkeveld) released generally similar products, which consisted of abundant volatile aromatic and alkyl-substituted aromatic compounds. These results revealed the ability of small-scale hydrous pyrolysis to dissect extraterrestrial macromolecular material and thereby reveal its organic constitution.

Sephton, M. A.; Pillinger, C. T.; Gilmour, I.

1998-12-01

241

Highly porous thin films obtained by spray-gel technique  

NASA Astrophysics Data System (ADS)

Combining the spray pyrolysis and the sol-gel techniques (spray-gel) gives the possibility to produce very rough and highly diffuse films. This technique is suitable for producing multifunctional metal oxides for gas-sensing, electrochromism, microbattery, and photocatalysis applications; due to the fact that it yields a large interface between a solid and a gaseous/liquid medium. The process basically consists in producing an aerosol from a gel, which is sprayed over a hot substrate, where the film is going to grow. In this work we present the results on highly porous SnO2, WO3, and phosphotungstic acid (PWA) thin films obtained by spray-gel.

Solis, J. L.; Rodriguez, J.; Estrada, W.

2004-08-01

242

Method of forming a plasma sprayed interconnection layer on an electrode of an electrochemical cell  

DOEpatents

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.

Spengler, Charles J. (Murrysville, PA); Folser, George R. (Lower Burrell, PA); Vora, Shailesh D. (Monroeville, PA); Kuo, Lewis (Monroeville, PA); Richards, Von L. (Anyola, IN)

1995-01-01

243

Method of forming a plasma sprayed interconnection layer on an electrode of an electrochemical cell  

DOEpatents

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.

Spengler, C.J.; Folser, G.R.; Vora, S.D.; Kuo, L.; Richards, V.L.

1995-06-20

244

Spot-spraying Johnsongrass.  

E-print Network

use of cultural methods supplemented by spot-spraying. Herbicidal oils and water solutions of sodium dalapon, sodium TCA and maleic hydrazide are some of the sprays used for spot-treating Johnsongrass. Oils are commonly applied to the crown. Water... mixture of 40 pounds of sodium TCA and 20 pounds of sodium dalapon can be used for spot-treating sparsely infested cotton fields. It is a knock-out spray under some conditions. Maleic hydrazide (MH-30) is a translocated growth inhibitor with no residual...

Rea, H. E.

1958-01-01

245

Oxymetazoline Nasal Spray  

MedlinePLUS

Afrin® Nasal Spray ... Anefrin® Nasal Spray ... Dristan® Nasal Spray ... Mucinex® Nasal Spray ... Nostrilla® Nasal Spray ... Vicks Sinex® Nasal Spray ... Zicam® Nasal Spray ... Oxymetazoline nasal spray is used to relieve nasal discomfort caused by colds, allergies, and hay fever. It is also used to ...

246

Relationship between hydrous and ordinary pyrolysis  

SciTech Connect

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.

Burnham, A.K.

1993-06-01

247

Optimisation of a vertical spray boom for greenhouse spraying applications.  

PubMed

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. PMID:15151329

Nuyttens, D; Windey, S; Braekman, P; De Moor, A; Sonck, B

2003-01-01

248

DEVELOPMENT OF THE THERMAL SPRAYING PROCESS FOR SURFACE COATING  

Microsoft Academic Search

Most commonly used methods of anticorrosion protection of large metal structures are painting and metal spraying. Painting is considerably cheaper than metal spraying, but the latter gives structures protection up to 20 years and reduces maintenance costs substantially. Metal spraying is typically achieved by spraying of molten zinc, aluminium or their alloys using thermal spraying technologies, such as Wire Flame

Igor A. Gorlach; Daniela Ghelase; Nelson Mandela

249

Stabilization of Fast Pyrolysis Oil: Post Processing Final Report  

SciTech Connect

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.

Elliott, Douglas C.; Lee, Suh-Jane; Hart, Todd R.

2012-03-01

250

The effects of biomass pretreatments on the products of fast pyrolysis  

Microsoft Academic Search

Fast pyrolysis thermochemically degrades lignocellulosic material into solid char, organic liquids, and gaseous products. Using fast pyrolysis to produce renewable liquid bio-oil to replace crude oil is gaining commercial interest. The production of pyrolysis bio-oil needs to be improved through standardization. Only with standard operational methods can pyrolysis bio-oil be commercially refined into chemicals or transportation fuels. Pretreatments such as

Randall Dennis Kasparbauer

2009-01-01

251

Characterization of the pyrolysis products of methiopropamine.  

PubMed

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, ?-carbon oxidation, ?-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. PMID:24166818

Bouso, Emily D; Gardner, Elizabeth A; O'Brien, John E; Talbot, Brian; Kavanagh, Pierce V

2014-01-01

252

Method of making supercritical fluid molecular spray films, powder and fibers  

DOEpatents

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.

Smith, Richard D. (Richland, WA)

1988-01-01

253

Generation of functional structures by laser pyrolysis of polysilazane  

NASA Astrophysics Data System (ADS)

The pyrolysis of polysilazanes by laser power represents an innovative technique for the generation of ceramic-like coatings and structures. The dissolved polysilazanes can be easily applied by painting techniques such as dipping or spraying. In the following pyrolysis the polysilazane layer transforms into an amorphous ceramic-like coating. The laser power is absorbed in the precursor layer, which leads to the latter's ceramization without damaging the substrate by thermal load. While plane laser pyrolysis creates a protective coating, selective pyrolysis creates a raised and adherent ceramic-like structure that remains after the unexposed polymer layer has been removed. The flexibility of a writing laser system in conjunction with a suitable handling system makes it possible to inscribe any kind of 2D structure on nearly any complexly shaped part. Some of the chemical, magnetic, and electrical structure properties can be adjusted by the pyrolysis parameters and special types of filler particles. Especially the possibility to control electric conductivity should make it possible to create structure dielectric films or planar resistors, inductors or capacitors, which are basically written on the surface of the part. Because of their ceramic nature of the structures are resistant against high temperatures and corrosive media. Thus, this new additive structuring technique could finally strike a new path in creating corrosion resistant high- temperature sensors and control systems.

Krauss, Hans-Joachim; Otto, Andreas

2002-06-01

254

Modelling of pyrolysis of large wood particles.  

PubMed

A fully transient mathematical model has been developed to describe the pyrolysis of large biomass particles. The kinetic model consists of both primary and secondary reactions. The heat transfer model includes conductive and internal convection within the particle and convective and radiative heat transfer between the external surface and the bulk. An implicit Finite Volume Method (FVM) with Tridiagonal Matrix Algorithm (TDMA) is employed to solve the energy conservation equation. Experimental investigations are carried out for wood fines and large wood cylinder and sphere in an electrically heated furnace under inert atmosphere. The model predictions for temperature and mass loss histories are in excellent agreement with experimental results. The effect of internal convection and particle shrinkage on pyrolysis behaviour is investigated and found to be significant. Finally, simulation studies are carried out to analyze the effect of bulk temperature and particle size on total pyrolysis time and the final yield of char. PMID:19231172

Sadhukhan, Anup Kumar; Gupta, Parthapratim; Saha, Ranajit Kumar

2009-06-01

255

Modeling of the APS plasma spray process  

Microsoft Academic Search

Coating production by means of thermal spraying processes offers a wide range of applications such as coatings for wear and corrosion protection or decorative applications. Thermal spraying methods for the production of functional coatings on technical surfaces have been developed and optimized for more than 30 years. Especially the plasma spraying method enables due to the high process temperatures the

E. Lugscheider; C. Barimani; P. Eckert; U. Eritt

1996-01-01

256

Spray Calendar.  

E-print Network

, dogs, pol try, cows, horses, and sprinliling halls, etc. The knapsack spray pun Figure 1, may also be used with equal success on small gardei shrubbery, etc., and is used considerably in large gardens. Consta pumping is required by the operator..., dogs, pol try, cows, horses, and sprinliling halls, etc. The knapsack spray pun Figure 1, may also be used with equal success on small gardei shrubbery, etc., and is used considerably in large gardens. Consta pumping is required by the operator...

Sanborn, C. E. (Charles Emerson)

1908-01-01

257

Toxicity of pyrolysis gases from polytetrafluoroethylene  

NASA Technical Reports Server (NTRS)

A sample of polytetrafluoroethylene was evaluated for toxicity of pyrolysis gases, using various test conditions of the toxicity screening test method developed at the University of San Francisco. Time to death appears to be affected by the material of which the pyrolysis tube is made, with Monel tending to give longer times to death than quartz. When quartz tubes are used, time to death seems to be related to carbon monoxide concentration. When Monel tubes are used, carbon monoxide does not appear to be the principal toxicant.

Hilado, C. J.; Schneider, J. E.

1979-01-01

258

Vacuum Plasma Spraying Replaces Electrodeposition  

NASA Technical Reports Server (NTRS)

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.

Holmes, Richard R.; Power, Chris; Burns, David H.; Daniel, Ron; Mckechnie, Timothy N.

1992-01-01

259

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)

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.

Shih, Tsan-Hsing; Liu, Nan-Suey

2012-01-01

260

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...

261

Control of spray spot shape in cold spray technology. Part 2. Spraying process  

NASA Astrophysics Data System (ADS)

The present paper studies high-velocity heterogeneous flows produced with nozzle designs unconventional for cold spray; the process of coating deposition was studied under these conditions. The possibility of using unconventional gas dynamic tools (swirling of main flow, nozzles with permeable profiles and with slots in the supersonic part of nozzle) for control of particle distribution in the supersonic jet is investigated: this might be useful for obtaining a proper shape of the spray spot. These experiments offered a method of gas-dynamic design for the spray spot shape, which extends the possibilities of cold spray technique.

Zaikovskii, V. N.; Klinkov, S. V.; Kosarev, V. F.; Melamed, B. M.; Trubacheev, G. V.

2014-04-01

262

Modelling of pyrolysis of large wood particles  

Microsoft Academic Search

A fully transient mathematical model has been developed to describe the pyrolysis of large biomass particles. The kinetic model consists of both primary and secondary reactions. The heat transfer model includes conductive and internal convection within the particle and convective and radiative heat transfer between the external surface and the bulk. An implicit Finite Volume Method (FVM) with Tridiagonal Matrix

Anup Kumar Sadhukhan; Parthapratim Gupta; Ranajit Kumar Saha

2009-01-01

263

Toxicity of pyrolysis gases from polypropylene  

NASA Technical Reports Server (NTRS)

A sample of polypropylene was evaluated for toxicity of pyrolysis gases, using the toxicity screening test method developed at the University of San Francisco. The gases from this sample appeared to be equivalent or less toxic than the gases from a sample of polyethylene under these particular test conditions. Carbon monoxide appeared to be the principal toxicant.

Hilado, C. J.; Schneider, J. E.; Brauer, D. F.

1979-01-01

264

Toxicity of pyrolysis gases from foam plastics  

NASA Technical Reports Server (NTRS)

Twenty-three samples of flexible foams and twelve samples of rigid foams were evaluated for toxicity of pyrolysis gases, using the USF toxicity screening test method. Polychloroprene among the flexible foams, and polystyrene among the rigid foams, appeared to exhibit the least toxicity under these particular test conditions.

Hilado, C. J.; Cumming, H. J.; Casey, C. J.

1980-01-01

265

The comparison of seven different methods to quantify the amorphous content of spray dried lactose  

Microsoft Academic Search

The purpose of this work was to verify the usefulness, advantages and disadvantages of seven methods that are widely used to detect, and quantify the amorphous contents in pharmaceutical solids. Here, StepScan DSC, a type of modulated temperature calorimetry method, was applied for the first time to quantify amorphicity. The comparison of the analytical methods was undertaken with real (non-artificial)

Vesa-Pekka Lehto; Mikko Tenho; Kalle Vähä-Heikkilä; Päivi Harjunen; Maarit Päällysaho; Jouni Välisaari; Pentti Niemelä; Kristiina Järvinen

2006-01-01

266

Additives initiate selective production of chemicals from biomass pyrolysis.  

PubMed

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. PMID:24508091

Leng, Shuai; Wang, Xinde; Wang, Lei; Qiu, Huizhe; Zhuang, Guilin; Zhong, Xing; Wang, Jianguo; Ma, Fengyun; Liu, Jingmei; Wang, Qiang

2014-03-01

267

Production of p-xylene from biomass by catalytic fast pyrolysis using ZSM-5 catalysts with reduced pore openings.  

PubMed

Pores for thought: Chemical liquid deposition of silica onto ZSM-5 catalysts led to smaller pore openings that resulted in >90% selectivity for p-xylene over the other xylenes in the catalytic fast pyrolysis of furan and 2-methylfuran (see scheme). The p-xylene selectivity increased from 51% with gallium spray-dried ZSM-5 to 72% with a pore-mouth-modified catalyst in the pyrolysis of pine wood. PMID:23038098

Cheng, Yu-Ting; Wang, Zhuopeng; Gilbert, Christopher J; Fan, Wei; Huber, George W

2012-10-29

268

Thermal spray processing  

NASA Technical Reports Server (NTRS)

Thermal spray processing has been used for a number of years to cost-effecticely apply TBC's for a wide range of heat engine applications. In particular, bond coats are applied by plasma spray and HVOF techniques and partially-stabilized zirconia top coats are applied by plasma spray methods. Thermal spray involves melting and rapid transport of the molten particles to the substrate, where high-rate solidification and coating build-up occur. It is the very nature of this melt processing that leads to the unique layered microstructure, as well as the apparent imperfections, so readily identified with thermal spray. Modeling the process, process-induced residual stresses, and thermal conductivity will be discussed in light of a new understanding of porosity and its anisotropy. Microcracking can be understood using new approaches, allowing a fuller view of the processing-performance connection. Detailed electron microscopic, novel neutron diffraction and fracture analysis of the deposits can lead to a better understanding of how overall microstructure can be controlled to influence critical properties of the deposited TBC system.

Herman, H.; Berndt, C. C.

1995-01-01

269

Spray plasma device, a new method to process nanostructured layers. application to deposit ZnO thin layers.  

PubMed

The aim of this paper is to present a new plasma spray device to deposit nanostructured films. In this process, aqueous droplets of a starting material, in this case, a nitrate salt, of small and uniform size produced in an aerosol generator are injected into a low pressure plasma reactor. Droplets are then submitted to the reactivity of plasma and projected against a substrate where they form the final film. The reactor is designed to reduce the turbulence that results in coalescence of the particles and affects the uniformity of the deposited films. The plasma is produced by an inductive RF generator that avoids the contamination of the layers by electrodes. The control of plasma gas composition, i.e., argon and oxygen, permits adjustment of the concentration of reactive species leading to control the stoichiometry of the deposited layers. The ability of this process to produce nano scale zinc oxide films by the use of an aqueous solution containing Zn(NO3)2 is demonstrated. The films obtained under defined experimental conditions are smooth, colorless and transparent. SEM and AFM photographs show the formation of uniform layers with 20 to 60 nm in thickness. XRD patterns of deposited films showed that preferential c-axis orientation of crystallites depends highly on the concentration of Zn(NO3)2 in the starting solution. Willamson-Hall method in accordance with AFM photographs showed that the size of crystallites ranges between 24 and 34 nm. PMID:20352774

Nikravech, Mehrdad

2010-02-01

270

Cellulose pyrolysis kinetics: Revisited  

SciTech Connect

In the same thermogravimetric analyzer (TGA) under identical conditions, samples of pure, ash-free cellulose (i.e., Avicel PH-105, Whatman CF-11, Millipore ash-free filter pulp, and Whatman No. 42) obtained from different manufacturers undergo pyrolysis at temperatures which differ by as much as 30 C. Thus, the pyrolysis chemistry of a sample of pure cellulose is not governed by a universal rate law, as is the case with a pure hydrocarbon gas (for example). Nevertheless, the pyrolytic weight loss of all the samples studied in this work is well represented by a high activation energy (228 kJ/mol), first-order rate law at both low and high heating rates. These results do not corroborate the recent findings of Milosavljevic and Suuberg. For a particular cellulose sample (for example, Avicel PH-105), variations in the preexponential constant determined at different heating rates reflect uncontrolled, systematic errors in the dynamic sample temperature measurement (thermal lag).

Antal, M.J. Jr. [Univ. of Hawaii, Honolulu, HI (United States)] [Univ. of Hawaii, Honolulu, HI (United States); Varhegyi, G.; Jakab, E. [Hungarian Academy of Sciences, Budapest (Hungary). Research Lab. for Materials and Environmental Chemistry] [Hungarian Academy of Sciences, Budapest (Hungary). Research Lab. for Materials and Environmental Chemistry

1998-04-01

271

Plasma spraying method for forming diamond and diamond-like coatings  

DOEpatents

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.

Holcombe, Cressie E. (Farragut, TN); Seals, Roland D. (Oak Ridge, TN); Price, R. Eugene (Knoxville, TN)

1997-01-01

272

Influence of Wet Storage of Spruce Wood on Groundwater Quality: Investigations by Water-Chemical Methods, Pyrolysis-Fieldionization Mass Spectrometry and Luminiscent-Bacteria Bioassay  

Microsoft Academic Search

For groundwater below a wet-storage location for spruce wood, water-chemical analyses indicated a distinct pollution by inorganic and organic compounds. Due to the high ammonium concentration mis groundwater was not suitable as drinking water. Using pyrolysis-field ionization mass spectrometry, a direct and fast molecular-chemical characterization of the organic constituents in the polluted groundwater was possible. No pretreatment except freeze-drying was

C. Sorge; H.-R. Schulten; R. G. Weyandt; N. Kamp; M. Brechtel

1994-01-01

273

Substrate system for spray forming  

DOEpatents

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.

Chu, Men G. (Export, PA); Chernicoff, William P. (Harrisburg, PA)

2000-01-01

274

Substrate system for spray forming  

DOEpatents

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.

Chu, Men G. (Export, PA); Chernicoff, William P. (Harrisburg, PA)

2002-01-01

275

AN ALTERNATIVE SCHEME FOR STIFFENING SRF CAVITIES BY PLASMA SPRAYING  

E-print Network

temperature plasma and the molten particles are sprayed out of the plasma gun. Depending on the sprayingAN ALTERNATIVE SCHEME FOR STIFFENING SRF CAVITIES BY PLASMA SPRAYING S.Bousson, M.Fouaidy, H propose a new stiffening method, using a Plasma Sprayed Copper Layer (PSCL) onto bulk niobium cavities

Paris-Sud XI, Université de

276

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

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. PMID:23160638

Pantazis, Christopher J; Fisk, Sarah; Mills, Kerri; Flinn, Barry S; Shulaev, Vladimir; Veilleux, Richard E; Dan, Yinghui

2013-03-01

277

Average structural analysis of tar obtained from pyrolysis of wood  

Microsoft Academic Search

Conventional analytical methods such as 1H NMR, vapor pressure osmometry (VPO) and elemental analysis were used to characterize the tar obtained from pyrolysis of pine.The major fraction of tar obtained during pyrolysis of pine at different temperatures was the insoluble fraction in n-heptane which corresponds to asphaltenes; this fraction was characterized and analyzed using average structural parameters. The structural unit

Diana López; Nancy Acelas; Fanor Mondragón

2010-01-01

278

Application of analytical pyrolysis for wood fire protection control  

Microsoft Academic Search

The effect of two flame-retardant compositions (A-76% potassium carbonate, B-67% sulphate ammonium) on the process of thermal degradation of wood and the composition of volatile products of pyrolysis has been investigated by the thermogravimetry and analytical pyrolysis methods. It has been shown that the effect of flame retardants manifests itself in the low-temperature region with the formation of more thermally

G. Dobele; I. Urbanovich; A. Zhurins; V. Kampars; D. Meier

2007-01-01

279

Non-isothermal pyrolysis kinetics of three Turkish oil shales  

Microsoft Academic Search

A non-isothermal experimental study using thermogravimetric analysis (t.g.a.) was conducted to determine the overall kinetics of pyrolysis of three Turkish oil shales: Beypazari, Seyitömer and Himmeto?lu. The integral method was used in the analysis of the t.g.a. data to determine first-order pyrolysis kinetics. Particle sizes of 0.7, 1.3 and 2.6 mm and final temperatures of 400, 550 and 700°C were

Ö. Murat Do?an; B. Zühtü Uysal

1996-01-01

280

Spray pyrolysed microporous TiO2 thin films by optimisation of substrate temperature for ‘all sprayed’ solar cells  

NASA Astrophysics Data System (ADS)

Titanium dioxide thin films were deposited on glass substrate at temperatures ranging from 300 °C to 500 °C by a simple, cost effective spray pyrolysis method using commercially available TiO2 powder (Degussa P25). Analyses using scanning electron microscopy (SEM) and atomic force microscopy (AFM) reveal the microporous nature of the films at 350 °C. X-ray diffraction (XRD) and Raman studies reveal that these films are amorphous in nature. The films were subsequently annealed at 500 °C for 2 h, resulting in crystallisation (the tetragonal anatase phase). XPS analysis was effectively used to study the chemical composition of the samples. Finally, optimized microporous TiO2 thin films were used for the fabrication of an ‘all-sprayed’ solar cell utilizing well-established CuInS2 as the absorber layer. The best device under this study has an open-circuit voltage of 409 mV and a short-circuit current density of 3.90 mA cm?2. The efficiency and fill factor were 0.61% and 38%, respectively.

Santhosh, M. V.; Deepu, D. R.; Geethu, R.; Rajeev Kumar, K.; Sudha Kartha, C.; Vijayakumar, K. P.

2014-11-01

281

Agricultural Spraying  

NASA Technical Reports Server (NTRS)

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.

1986-01-01

282

Reacting Sprays  

Microsoft Academic Search

\\u000a The classification regimes for premixed and non-premixed combustion processes are discussed in terms of the Damköhler and\\u000a Karlovitz numbers. Dec’s diesel spray combustion concept is introduced, followed by a short review of chemical kinetics. The\\u000a ignition process together with appropriate models is then discussed. Subsequently, various combustion models are presented,\\u000a including mixing-controlled, flamelet and PDF combustion models. The chapter ends

F. X. Tanner

283

Vacuum pyrolysis of sugarcane bagasse  

Microsoft Academic Search

The objective of this study was to provide background data on sugarcane bagasse vacuum pyrolysis. Product yields and properties were investigated. Vacuum pyrolysis tests were performed at bench and pilot plant scales. The bagasse finest particles with a diameter smaller than 450 ?m were removed in order to overcome difficulties caused by their low density and high ash content. In

Abdelkader Chaala; Christian Roy

2002-01-01

284

Fast pyrolysis processes for biomass  

Microsoft Academic Search

Fast pyrolysis for production of liquids has developed considerably since the first experiments in the late 1970s. Many reactors and processes have been investigated and developed to the point where fast pyrolysis is now an accepted feasible and viable route to renewable liquid fuels, chemicals and derived products. It is also now clear that liquid products offer significant advantages in

A. V. Bridgwater; G. V. C. Peacocke

2000-01-01

285

Acoustic microscopy of functionally graded thermal sprayed coatings using1 stiffness matrix method and Stroh formalism2  

E-print Network

substrate is treated as a functionally graded material along the depth of the coating and is approximately31 1 Acoustic microscopy of functionally graded thermal sprayed coatings using1 stiffness of multilayered media as well as functionally graded coatings on substrate24 necessitates to model acoustic

Paris-Sud XI, Université de

286

Corrosivity Of Pyrolysis Oils  

SciTech Connect

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.

Keiser, James R [ORNL] [ORNL; Bestor, Michael A [ORNL] [ORNL; Lewis Sr, Samuel Arthur [ORNL] [ORNL; Storey, John Morse [ORNL] [ORNL

2011-01-01

287

TG-DSC-FTIR Analysis of Cyanobacteria Pyrolysis  

NASA Astrophysics Data System (ADS)

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.

Supeng, Luo; Guirong, Bao; Hua, Wang; Fashe, Li; Yizhe, Li

288

Method of forming a leak proof plasma sprayed interconnection layer on an electrode of an electrochemical cell  

DOEpatents

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.

Kuo, L.J.H.; Vora, S.D.

1995-02-21

289

Method of forming a leak proof plasma sprayed interconnection layer on an electrode of an electrochemical cell  

DOEpatents

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.

Kuo, Lewis J. H. (Monroeville, PA); Vora, Shailesh D. (Monroeville, PA)

1995-01-01

290

Structure and pyrolysis characteristics of lignin derived from wood powder hydrolysis residues.  

PubMed

Physicochemical characteristics of wood powder acid hydrolysis residue (WAHR) were studied firstly in this study, and WAHL (lignin derived from WAHR) was separated successfully from WAHR based on an improved isolating method. The content of functional group such as phenolic hydroxyl group of guaiacyl, syringyl, and hydroxyl-phenyl units in WAHL were identified by (31)P-NMR and DFRC (derivatization followed by reductive cleavage) method. Thermal degradation experiments were carried out on a thermogravimetric (TG) analyzer to show pyrolysis characteristics of WAHL. The compositions of pyrolysis products of WAHL were also studied throughout a pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) analyzer. It was shown that the pyrolysis of WAHL took place in a wide temperature range and there were two obvious peaks in the differential thermogravimetric diagram. Results of Py-GC-MS analysis indicated that pyrolysis products were mainly formed through cleavage of the ?-O-4 connection and multiple pyrolysis. PMID:21603951

Zhang, Bin; Yin, Xiuli; Wu, Chuangzhi; Qiu, Zejing; Wang, Congwei; Huang, Yanqin; Ma, Longlong; Wu, Shubin

2012-09-01

291

Kinetics of scrap tyre pyrolysis under vacuum conditions  

SciTech Connect

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.

Lopez, Gartzen; Aguado, Roberto [Departamento de Ingenieria Quimica, Universidad del Pais Vasco, Apartado 644, 48080 Bilbao (Spain); Olazar, Martin [Departamento de Ingenieria Quimica, Universidad del Pais Vasco, Apartado 644, 48080 Bilbao (Spain)], E-mail: martin.olazar@ehu.es; Arabiourrutia, Miriam; Bilbao, Javier [Departamento de Ingenieria Quimica, Universidad del Pais Vasco, Apartado 644, 48080 Bilbao (Spain)

2009-10-15

292

Vacuum pyrolysis of PVC I. Kinetic study  

Microsoft Academic Search

Vacuum pyrolysis of PVC has been studied emphasizing two aspects: the kinetics of PVC pyrolysis reactions and the yields of pyrolysis products. The purpose of the kinetic study is to identify each apparent reaction involved in PVC pyrolysis. Three stages of weight loss have been evidenced by TG analysis during PVC decomposition both under vacuum and in nitrogen atmosphere, while

Rosa Miranda; Jin Yang; Christian Roy; Cornelia Vasile

1999-01-01

293

Hydrocarbon-rich Products from Sunflower Oil by Alkali Catalytic Pyrolysis  

Microsoft Academic Search

Possible acceptable recycling processes of vegetable oils are cracking and pyrolysis. Pyrolysis is a common practice and an effective method for recycling waste disposal. The sunflower oil can be pyrolyzed into hydrocarbon-rich products. Alkali (Na2CO3) was used in the pyrolysis experiments. Interest is focused on gasoline-rich engine fuel production. The liquid products are usually composed of higher boiling point hydrocarbons.

A. Demirbas

2009-01-01

294

Comparison of petroleum generation kinetics by isothermal hydrous and nonisothermal open-system pyrolysis  

Microsoft Academic Search

This study compares kinetic parameters determined by open-system pyrolysis and hydrous pyrolysis using aliquots of source rocks containing different kerogen types. Kinetic parameters derived from these two pyrolysis methods not only differ in the conditions employed and products generated, but also in the derivation of the kinetic parameters (i.e., isothermal linear regression and non-isothermal nonlinear regression). Results of this comparative

M. D. Lewan; T. E. Ruble

2002-01-01

295

Discrimination of genetically modified poplar clones by analytical pyrolysis–gas chromatography and principal component analysis  

Microsoft Academic Search

Analytical pyrolysis combined with gas chromatography and mass spectrometry (Py-GC–MS) is a relatively rapid (1–3h) method for the investigation of polymers. Various wood tissues from transgenic poplar clones and from control samples have been subjected to a screening test by Py-GC–MS. Pyrolysis products from lignin- and carbohydrate-derived pyrolysis products were subjected to multivariate principal component analysis (PCA). The first three

Dietrich Meier; Ingrid Fortmann; Jürgen Odermatt; Oskar Faix

2005-01-01

296

Discrimination of three tobacco types (Burley, Virginia and Oriental) by pyrolysis single-photon ionisation-time-of-flight mass spectrometry and advanced statistical methods.  

PubMed

Pyrolysis single-photon ionisation (SPI)-time-of-flight mass spectrometry (TOFMS) and statistical analysis techniques have been applied to differentiate three major tobacco types, Burley, Virginia and Oriental, by means of the gas phase. SPI is known as a soft ionisation technique that allows fast and comprehensive on-line monitoring of a large variety of aliphatic and aromatic substances without fragmentation of the molecule ions. The tobacco samples were pyrolysed at 800 degrees C in a nitrogen atmosphere. The resulting pyrolysis gas contained signals from more than 70 masses between m/z 5 and 170. Mass spectra obtained were analysed by principal component analysis (PCA) and linear discriminant analysis (LDA) to distinguish between different tobacco types. Prior variable reduction of the data set was carried out by calculation of the Fisher ratios. Results achieved give information about chemical composition and characteristics of the smoke derived from each tobacco type and enable conclusions on plant cultivation to be drawn. Based on LDA, a model for tobacco type recognition of unknown samples was established, which was cross-checked by additional measurements of each tobacco type. Furthermore, first results on the recognition of tobacco mixtures based on principal component regression (PCR) are presented. PMID:15599713

Adam, T; Ferge, T; Mitschke, S; Streibel, T; Baker, R R; Zimmermann, R

2005-01-01

297

Volatile constituents in a wood pyrolysis oil  

E-print Network

Science VOLATILE CONSTITUTENTS IN A WOOD PYROLYSIS OIL A Thesis SHIH-CHIEN LIN Appro d as to style and content by: (Chairman of Committee) Head of epa tmen (Member Member Nay 1978 442936 ABSTRACT Volatile Constituents in a Wood Pyrolysis Oil..., 1958]. . . . . . . . . . . . 4 Pyrolysis products of cellulose and treated cellulose at 600oC f Chin, 1973]. . . . . . . . . . . . . . . 6 3. Pyrolysis products of lignin at 450-550 C [Allen and Nattil a, 1971] Properties of wood pyrolysis oil. 12...

Lin, Shih-Chien

2012-06-07

298

Status of Process Development for Pyrolysis of Biomass for Liquid Fuels and Chemicals Production.  

SciTech Connect

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.

Elliott, Douglas C.

2010-06-01

299

Fracture toughness measurements of plasma-sprayed thermal barrier coatings using a modified four-point bending method  

Microsoft Academic Search

In this study, the adhesion strength of thermal barrier coatings 8YSZ (ZrO2+8wt.% Y2O3) deposited on NiCrAlY bond coats by atmospheric plasma spraying is investigated experimentally. A modified four-point bending specimen that can generate a single interface crack to facilitate the control of crack growth was adopted for testing. The fracture surfaces were examined using a scanning electron microscope. Images show

P. F. Zhao; C. A. Sun; X. Y. Zhu; F. L. Shang; C. J. Li

2010-01-01

300

Analysis of energy production systems integrated with coal pyrolysis  

SciTech Connect

Coal pyrolysis technology carried out in a circulating fluidized bed reactor, according to the method developed by the Institute for Chemical Processing of Coal, offers possibilities to significantly decrease coal consumption in both the industrial and the communal sectors of the national economy. Pyrolysis can be considered a primary process of coal conversion that in integrated systems provides high efficiency together with full environmental protection. In the communal sector, integration of pyrolysis with smokeless solid fuel manufacturing enables users to save approximately 26 to 32 % of the amount of coal used in a power plant equipped with a gas-steam combiblock. The technical solution is simple and easily adaptable in industry. The paper discusses high temperature coal degasification in a circulating fluidized bed reactor; typical data of the coal degasification process; the communal and individual coal consumers sector; general overview of the combined cycle; structure of the combined cycle integrated with a coal degasification plant; and thermodynamic parameters of the combined gas-steam cycle. Integrating pyrolysis technology with smokeless fuel production results in a new type of solid fuel for the internal energy market in Poland. Integrating pyrolysis with a power plant leads to the utilization of coal gas in a gas turbine. The second pyrolysis product, char, is burned in a circulating fluidized bed boiler.

Chmielniak, T.; Kotowicz, J. [Silesian Technical Univ., Gliwice (Poland). Institute of Power Generation Engineering; Kaczmarzyk, G.; Sciazko, M. [Institute for Chemical Processing of Coal, Zabrze (Poland)

1994-12-31

301

Concentration-response data on toxicity of pyrolysis gases from some natural and synthetic polymers  

NASA Technical Reports Server (NTRS)

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.

Hilado, C. J.; Huttlinger, N. V.

1978-01-01

302

Effect of pyrolysis temperature on toxicity of gases from a polyethylene polymer  

NASA Technical Reports Server (NTRS)

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.

Hilado, C. J.; Kosola, K. L.

1978-01-01

303

Coal pyrolysis in a rotary kiln: Part 1. Model of the pyrolysis of a single grain  

SciTech Connect

A mathematical model is presented which describes the pyrolysis of a single grain of coal and is designed to be incorporated into an overall model simulating the rotary kiln coal pyrolysis process. The grain model takes into account the principal physical phenomena occurring during the conversion of coal to coke, namely, heat transfer toward and within the grain, drying of the coal, and the evolution of volatile species. Particular care has been taken in the determination of the thermophysical and kinetic parameters necessary for the model. Thus, the drying kinetics for Lorraine coal were measured by thermogravimetry. The kinetics of pyrolysis were determined by both thermogravimetry and gas-phase chromatography, in order to separately monitor the evolution of the nine gaseous species considered. The true specific heat and the thermal conductivity of the solid were also measured as a function of temperature. The numerical model, based on the finite-volume method, calculates the temperature, composition, and mass flow rates for the different gases evolved at each point in the grain at any instant of time. The model was, finally, validated by comparing the calculated and measured values of the overall conversion of the pyrolysis reaction and the temperature at the center of the grain.

Patisson, F.; Lebas, E.; Hanrot, F.; Ablitzer, D.; Houzelot, J.L.

2000-04-01

304

Coal pyrolysis in a rotary kiln: Part I. Model of the pyrolysis of a single grain  

NASA Astrophysics Data System (ADS)

A mathematical model is presented which describes the pyrolysis of a single grain of coal and is designed to be incorporated into an overall model simulating the rotary kiln coal pyrolysis process. The grain model takes into account the principal physical phenomena occurring during the conversion of coal to coke, namely, heat transfer toward and within the grain, drying of the coal, and the evolution of volatile species. Particular care has been taken in the determination of the thermophysical and kinetic parameters necessary for the model. Thus, the drying kinetics for Lorraine coal were measured by thermogravimetry. The kinetics of pyrolysis were determined by both thermogravimetry and gasphase chromatography, in order to separately monitor the evolution of the nine gaseous species considered. The true specific heat and the thermal conductivity of the solid were also measured as a function of temperature. The numerical model, based on the finite-volume method, calculates the temperature, composition, and mass flow rates for the different gases evolved at each point in the grain at any instant of time. The model was, finally, validated by comparing the calculated and measured values of the overall conversion of the pyrolysis reaction and the temperature at the center of the grain.

Patisson, Fabrice; Lebas, Etienne; Hanrot, François; Ablitzer, Denis; Houzelot, Jean-Leon

2000-04-01

305

Detection of segmentation cracks in top coat of thermal barrier coatings during plasma spraying by non-contact acoustic emission method  

NASA Astrophysics Data System (ADS)

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.

Ito, Kaita; Kuriki, Hitoshi; Araki, Hiroshi; Kuroda, Seiji; Enoki, Manabu

2014-06-01

306

Synthesis and photocatalytic property of graphene/multi-walled carbon nanotube/ZnO nanocrystalline aggregates hybrids by spray drying method  

NASA Astrophysics Data System (ADS)

The novel 3D graphene oxide/multi-walled carbon nanotubes/ZnO nanocrystalline aggregate (GR/MWNTs/ZnO) hybrids were prepared by a spray drying method, and their adsorption and photocatalytic degradation for methyl orange (MO) were studied. Experimental results show that the synthetic GR/MWNTs/ZnO nanohybrids exhibited very strong adsorption capacity and high photocatalytic activity for MO. The maximum adsorption capacity of GR/MWNTs/ZnO sample reached 106.2 mg/g, and the photocatalytic efficiency of ZnO nanocrystallines was improved about one time by GR/MWNTs hybrids.

Chen, C. S.; Cao, S. Y.; Zeng, B.; Ning, X. T.; Liu, T. G.; Chen, X. H.; Xiao, Y.; Yu, W. W.

2014-05-01

307

Comparison of spray pyrolyzed FTO, ATO and ITO coatings for flat and bent glass substrates  

Microsoft Academic Search

Transparent conductive FTO, ATO and ITO films were synthesized by spray pyrolysis technique on flat 12×12 cm borosilicate glass substrates at 500–550°C and investigated with respect to their electrical and optical properties. The resistivity of sprayed ITO films decreases with the thickness down to 3.0×10?4 ? cm (300 nm). The optical transmission in the visible range is 80% and the

H. Bisht; H.-T Eun; A Mehrtens; M. A Aegerter

1999-01-01

308

Kelvin spray ionization.  

PubMed

A novel self-powered dual spray ionization source has been developed for applications in mass spectrometry. This new source does not use any power supply and produces both positive and negative ions simultaneously. The idea behind this ionization source comes from the Kelvin water dropper. The source employs one or two syringes, two pneumatic sprays operated over a range of flow rates (0.15-15 ?L min(-1)) and gas pressures (0-150 psi), and two double layered metal screens for ion formation. A variable electrostatic potential from 0 to 4 kV can be produced depending on solvent and gas flow rates that allow gentle ionization of compounds. There are several parameters that affect the performance during ionization of molecules including the flow rate of solvent, gas pressure, solvent acidity, position of spray and metal screens with respect to each other and distance between metal screens and the counter electrode. This ionization method has been successfully applied to solutions of peptides, proteins and non-covalent complexes. In comparison with ESI, the charge number of the most populated state is lower than that from ESI. It indicates that this is a softer ionization technique and it produces more protein ions with folded structures. The unique features of Kelvin spray ionization (KeSI) are that the method is self-powered and ionization occurs at very low potentials by providing very low internal energy to the ions. This advantage can be used for the ionization of very fragile molecules and investigation of non-covalent interactions. PMID:24080942

Özdemir, Abdil; Lin, Jung-Lee; Gillig, Kent J; Chen, Chung-Hsuan

2013-11-21

309

Plasma Pyrolysis Assembly Regeneration Evaluation  

NASA Technical Reports Server (NTRS)

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.

Medlen, Amber; Abney, Morgan B.; Miller, Lee A.

2011-01-01

310

Comparison of properties of polymer organic solar cells prepared using highly conductive modified PEDOT:PSS films by spin- and spray-coating methods  

NASA Astrophysics Data System (ADS)

Bulk heterojunction (BHJ) solar cells have made great progress over the past decade and consequently are now attracting extensive academic and commercial interest because of their potential advantages: lightweight, flexible, low cost, and high-throughput production. Polymer conductivity is a key factor for improving the performance of electronic and photonic devices. Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is promising for use as a next-generation transparent electrode of optoelectronic devices. In this research, we compare the effect of nanomorphology on conductivity, and power conversion efficiency of polymer organic solar cells prepared by the spin- and spray-coating methods. To improve the conductivity of spray-deposited PEDOT:PSS, we modified the PEDOT:PSS films by simple UV irradiation and by UV irradiation with treatment using various solvents such as methanol, ethanol, acetone, acetonitrile, hydrochloric acid, and sulfuric acid to form a hole transport layer (HTL). The active layer of PTB7:PC70BM is spray-coated on top of the PEDOT:PSS layer. The films were examined by optical spectroscopy, micro-Raman spectroscopy, and conductivity measurements. The surface morphology of the deposited films was examined by atomic force microscopy (AFM). The current density-voltage (J-V) characteristics were measured under illumination with simulated solar light at 100 mW/cm2 (AM 1.5G) using an oriel 1000 W solar simulator. The obtained results are expected to have a considerable impact and suggest a bright future for organic polymer solar cells.

Kumar, Palanisamy; Santhakumar, Kannappan; Tatsugi, Jiro; Shin, Paik-Kyun; Ochiai, Shizuyasu

2014-01-01

311

Thin layer chromatography-spray mass spectrometry: a method for easy identification of synthesis products and UV filters from TLC aluminum foils.  

PubMed

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. PMID:24500757

Himmelsbach, Markus; Waser, Mario; Klampfl, Christian W

2014-06-01

312

Surface characteristic of chemically converted graphene coated low carbon steel by electro spray coating method for polymer electrolyte membrane fuel cell bipolar plate.  

PubMed

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. PMID:23858864

Kim, Jungsoo; Kim, Yang Do; Nam, Dae Geun

2013-05-01

313

Experimental studies on municipal solid waste pyrolysis in a laboratory-scale rotary kiln  

Microsoft Academic Search

A laboratory-scale, externally heated, rotary-kiln pyrolyser was designed and built. Pyrolysis tests were performed. Solid wastes (paper, paperboard, waste plastics including PVC and PE, rubber, vegetal materials, wood, and orange husk) were tested. The effects of heating methods, moisture contents and size of waste on pyrolysis gas yields and compositions, as well as heating values, were evaluated.

A. M Li; X. D Li; S. Q Li; Y Ren; N Shang; Y Chi; J. H Yan; K. F Cen

1999-01-01

314

A Heat Transfer Model for Cotton Fabric Pyrolysis Considering Nonlinear Shrinkage  

Microsoft Academic Search

This paper reported an improved computational model of pyrolysis of cotton fabric that exposed to a constant radiant heat flux. Shrinkage occurring in the char layer during the pyrolysis reactions was incorporated into the proposed detailed model. At present, gas phase oxidation reactions are not included and the model will be validated at next stage. The method for modeling will

Fang-long Zhu; Ke-jing Li

2010-01-01

315

Preliminary investigations on low-pressure laminar plasma spray processing  

Microsoft Academic Search

The usual plasma spraying methods often involve entrainment of the surrounding air into the turbulent plasma core and result in coated materials having relatively high porosity and low adhesive strength. Therefore, exploration of new plasma spraying methods for fabricating high quality coatings to meet the requirement of special applications will be quite important. In this study, an alternative plasma spraying

W. Ma; W. X. Pan; C. K. Wu

2005-01-01

316

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)

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.

Shih, Tsan-Hsing; Liu, Nan-Suey

2013-01-01

317

Plasma spray processing of TBC`s  

SciTech Connect

Thermal spray processing has been used for a number of years to cost-effectively apply TBC`s for a wide range of heat engine applications. In particular, bond coats are applied by vacuum plasma spray or HVOF techniques and partially-stabilized zirconia top coats are applied by plasma spray methods. Thermal spray involves melting and rapid transport of the molten particles to the substrate, where high-rate solidification and coating build-up occur. It is the very nature of this melt processing that leads to the unique layered microstructure, as well as the apparent imperfections, so readily identified with thermal spray. Therefore, although the plasma spray of TBCs has been largely successful, it is clear that a major step forward in terms of reliability and performance can be gained by a fundamental understanding of the TBC microstructure with respect to the processing technology and operating environment.

Herman, H.; Berndt, C.C.

1995-10-01

318

Thermal Spraying Coatings Assisted by Laser Treatment  

SciTech Connect

Coatings produced by air plasma spraying (APS) are widely used to protect components against abrasive wear and corrosion. However, APS coatings contain porosities and the properties of these coatings may thereby be reduced. To improve these properties, various methods could be proposed, including post-laser irradiation [1-4]. Firstly, PROTAL process (thermal spraying assisted by laser) has been developed as a palliative technique to degreasing and grit-blasting prior to thermal spraying. Secondly, thermal spray coatings are densified and remelted using Laser treatment. In this study, a review of microstructure coatings prepared by laser-assisted air plasma spraying will be presented. Mechanical and magnetic properties will be evaluated in relation to changes in the coating microstructure and the properties of such coatings will be compared with those of as-sprayed APS coatings.

Fenineche, N. E.; Cherigui, M. [LERMPS-UTBM (Site de Sevenans), 90010 Belfort Cedex (France)

2008-09-23

319

Blue TiO\\/SiO 2 nanoparticles by laser pyrolysis  

Microsoft Academic Search

Composite TiSiOC nanoparticles with Ti\\/Si ratio varying in a very large range were prepared by laser pyrolysis of a gas–spray mixture of silane and titanium tetra-isopropoxide. The as-formed nanoparticle batches exhibit intense blue colours, varying from dark to light blue while the Ti\\/Si ratio increases. This blue colour is attributed to the formation of sub-stoichiometric TiO$$_{2-x}$$compounds induced by the presence

Hicham Maskrot; Nathalie Herlin-Boime; Yann Leconte; Krystina Jursikova; Cécile Reynaud; Jean Vicens

2006-01-01

320

Pyrolysis kinetics of lignocellulosic materials  

SciTech Connect

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.

Balci, S.; Dogu, T.; Yuecel, H. (Middle East Technical Univ., Ankara (Turkey). Dept. of Chemical Engineering)

1993-11-01

321

An elastic-perfectly plastic model for simulating an aluminum particle behavior during plasma thermal spraying using the finite element method  

NASA Astrophysics Data System (ADS)

It is a 2D numerical study which treats the splat and flattening of the droplet during a thermal spraying process. An aluminum particle at a high temperature is impacted on steel substrate. A perfectly elastic-plastic model is used instead of the VOF method which is exclusively used in the literature. For this purpose, the finite element method with Ansys mechanical APDL program is used to solve the governing equations. Displacement, elastic and plastic strains, Von-Mises stress, energy densities, and contact pressure are evaluated during the impact of the particle. Additionally, it is found that the initial impact velocity has a significant effect on splat behavior. This mechanical model gives a promise results that can be improved to help understand the impact and flattening phenomenon.

Benramoul, L.; Abdellah El-Hadj, A.

2011-11-01

322

Early products of pyrolysis of wood  

Microsoft Academic Search

The authors are studying the first stages in pyrolysis of wood and other cellulosic materials as part of a study of the chemistry of smoldering or low-temperature combustion. In the latter processes both oxidative and non-oxidative pyrolysis occur. This paper describes an investigation of the first volatile products of pyrolysis of wood and they believe that many of the conclusions

W. F. De Groot; W. P. Pan; M. D. Rahman; G. N. Richards

1987-01-01

323

Dynamic characteristics of pulsed supersonic fuel sprays  

NASA Astrophysics Data System (ADS)

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.

Pianthong, K.; Matthujak, A.; Takayama, K.; Milton, B. E.; Behnia, M.

2008-06-01

324

Toxicity of pyrolysis gases from wood  

NASA Technical Reports Server (NTRS)

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.

Hilado, C. J.; Huttlinger, N. V.; Oneill, B. A.; Kourtides, D. A.; Parker, J. A.

1977-01-01

325

Spray modeling and measurements for pharmaceutical tablet coating applications  

Microsoft Academic Search

A method of spray modeling and measurements for pharmaceutical pan tablet coating applications is proposed. It consists of (1) spatially resolved spray characterization and (2) computational predictions of subsequent spray evolution using CFD. Both (1) and (2) are in line with PAT guidelines that emphasize process understanding and analytical process design.^ (1) utilizes a dual-mode Phase Doppler Anemometry (PDA) system.

Ariel Roland Muliadi

2009-01-01

326

Pyrolysis kinetics of hazelnut husk using thermogravimetric analysis.  

PubMed

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. PMID:24508656

Ceylan, Selim; Topçu, Y?ld?ray

2014-03-01

327

Application of a pyroprobe to simulate smoking and metabolic degradation of abused drugs through analytical pyrolysis.  

PubMed

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. PMID:17316254

Gayton-Ely, Melissa; Shakleya, Diaa M; Bell, Suzanne C

2007-03-01

328

Concentration-response data on toxicity of pyrolysis gases from six synthetic polymers  

NASA Technical Reports Server (NTRS)

Concentration-response data are presented on the toxic effects of the pyrolysis gases from six synthetic polymers on Swiss Webster male mice, using a toxicity screening test method. The polymers consisted of one sample each of polycarbonate and polystyrene, and two samples each of polyethylene and acrylonitrile-butadiene-styrene (ABS). All six samples were evaluated using the rising temperature program, and three samples were evaluated using the fixed temperature program. The pyrolysis gases from polycarbonate, polyethylene, and ABS appeared to exhibit the concentration-response relationships commonly encountered in toxicology. The polystyrene sample gave variable results; probably due to poor reproducibility of the essentially anaerobic pyrolysis. Carbon monoxide seemed to be the principal toxicant in the pyrolysis gases from polycarbonate and polyethylene, but did not appear to be the principal toxicant in the pyrolysis gases from ABS.

Hilado, C. J.; Huttlinger, N. V.

1978-01-01

329

Properties of alumina-based coatings deposited by plasma spray and detonation gun spray processes  

Microsoft Academic Search

Alumina, Al2O3 + 3 to 40 wt% TiO2, and Al2O3 + 40 wt% ZrO2 coatings were deposited by atmospheric plasma spraying (APS) and detonation gun spraying (DGS). The coatings were evaluated\\u000a by optical microscopy, microhardness measurements, and X- ray diffraction. Wear resistance of the coatings was evaluated by\\u000a rubber wheel sand abrasion and particle erosion test methods. Detonation gun- sprayed

K. Niemi; P. Vuoristo; T. Mäntylä

1994-01-01

330

Effect of cu ratio on the growth of sprayed Cu2ZnSnS4 film  

NASA Astrophysics Data System (ADS)

We fabricated Cu2ZnSnS4 (CZTS) films by using the spray pyrolysis and the post-sulfurization methods. CZTS films were sprayed with different Cu-ratio precursors (Cu-ratio: 1.6, 2.0, 2.4) and substrate temperatures (T s : 400, 430, 460 °C). In this substrate temperature ranges, the Curatio was found to have a more apparent effect on the growth of CZTS films than the substrate temperature. A higher Cu-ratio resulted in better crystallinity of the as-sprayed films, which was confirmed by using X-ray diffraction and Raman spectroscopy. In order to improve the crystallinity of the CZTS films, we carried out post-sulfurization, where the annealing temperature was increased to 568°C. After post-sulfurization, the crystallinity was improved for all CZTS films, which was also confirmed by using X-ray diffraction and Raman spectroscopy. CZTS films with higher Cu-ratios showed better crystallinity even in the post-sulfurized CZTS films.

Lee, HyunTai; Kim, JunHo

2012-06-01

331

Butorphanol Nasal Spray  

MedlinePLUS

Butorphanol nasal spray is used to relieve moderate to severe pain. Butorphanol is in a class of medications called opioid agonist- ... Butorphanol nasal spray comes as a solution (liquid) to spray in the nose. It is usually used as needed for pain, ...

332

Ciclesonide Nasal Spray  

MedlinePLUS

Ciclesonide nasal spray is used to treat the symptoms of seasonal (occurs only at certain times of the year), and perennial ( ... Ciclesonide comes as a solution (liquid) to spray in the nose. It is usually sprayed in each nostril once daily. Use ciclesonide at around the same time every day. Follow the ...

333

Fast pyrolysis of pretreated wood  

SciTech Connect

During the 1980`s, several research groups reported the fact that pyrolysis in a non-oxidizing atmosphere of wood that had been prehydrolyzed with dilute acid allowed a substantial depolymerization of the cellulose to occur to give anhydrosugars. More recent work has shown that only deionization of the wood is necessary, and not necessarily a partial hydrolysis. The indigineous alkaline inorganic cations contained in the wood (principally calcium and potassium) have a profound effect on the mechanism of thermal decomposition of the cellulose and hemicellulose fractions. Also, it has been known for many years that alkaline cations are efficient oxidation catalysts for biomass. We have explored the possibility that oxidation reactions in fast pyrolysis of prehydrolyzed, or of deionized, biomass may be altered much more for carbohydrates than for lignins. Results obtained show that fast pyrolysis of pretreated biomass with controlled levels of oxygen will selectively oxidize lignins with relatively little effect on anhydrosugar yields. This partial oxidation approach generated needed heat in situ. As well, by removing a substantial fraction of the lignin-derived material from the pyrolysis liquid, the recovery of anhydrosugars for use as fermentable sugars or as chemicals is simplified.

Piskorz, J.; Radlein, D.; Majerski, P. [Resource Transforms International Ltd, Ontario (Canada)] [and others

1995-11-01

334

Reduced mechanisms for propane pyrolysis  

Microsoft Academic Search

Reduced chemical mechanisms describing the pyrolysis of pure propane in a cracking tube with a uniform firebox temperature are presented. The full chemistry is taken from the model of Dente and Ranzi and consists of 422 reactions involving 48 species. By use of techniques for the identification of redundant species and the principal component analysis of the local rate sensitivity

Alison S. Tomlin; Michael J. Pilling; John H. Merkin; John Brindley; Neill Burgess; Arthur Gough

1995-01-01

335

Carbon nanoparticles from laser pyrolysis  

Microsoft Academic Search

Carbon nanoparticles synthesised by laser pyrolysis of hydrocarbons in a flow reactor have been investigated as a function of laser power. Samples are cross-characterised by high resolution transmission electron microscopy (HRTEM) and infrared (IR) spectroscopy. Nanoparticles appear highly aromatic in character in all the experimental conditions explored here. As the flame temperature in the interaction zone increases, the nanoparticles evolve

Aymeric Galvez; Nathalie Herlin-Boime; Cécile Reynaud; Christian Clinard; Jean-Noël Rouzaud

2002-01-01

336

Autothermal pyrolysis of waste tires  

SciTech Connect

The main objective of this research was to study the operating parameters of autothermal pyrolysis of scrap tires in a laboratory-scale fluidized bed reactor with a 100-cm bed height (10 cm I.D.) and a 100-cm freeboard (25 cm I.D.). Scrap tires were pyrolyzed in a limited oxygen supply, so that the heat for pyrolysis of the scrap tires was provided by combustion of some portion of the scrap tires. The operating parameters evaluated included the effect on the pyrolysis oil products and their relative proportions of (1) the air factor (0.07-0.035); (2) the pyrolysis temperature (370-570{degree}C); and (3) the catalyst added (zeolite and calcium carbonate). The results show that: (1) the composition of the liquid hydrocarbon obtained is affected significantly by the air factor; (2) the higher operating temperature caused a higher yield of gasoline and diesel; (3) the yield of gasoline increased due to the catalyst zeolite added, and the yield of diesel increased due to the addition of the catalyst calcium carbonate; (4) the principal constituents of gasoline included dipentene and diprene. 30 refs., 10 figs., 5 tabs.

Wey, M.Y.; Liou, B.H. [National Chung-Hsing Univ., Taichung (Taiwan, Province of China); Wu, S.Y.; Zhang, C.H. [Feng-Chia Univ., Taichung (Taiwan, Province of China)

1995-11-01

337

Drying and pyrolysis of wood particles: experiments and simulation  

Microsoft Academic Search

The objective of this study is to develop a flexible and stable numerical method to predict the thermal decomposition of large wood particles due to drying and pyrolysis. At a later stage, this model is applied to each particle of a packed bed and thus, forms the entire packed bed process as a sum of individual particle processes. Therefore, this

Bernhard Peters; Christian Bruch

2003-01-01

338

Comparative pyrolysis and combustion kinetics of oil shales  

Microsoft Academic Search

In this research, thermal characteristics and kinetic parameters of eight Turkish oil shale samples were determined by thermogravimetry (TG\\/DTG) at non-isothermal heating conditions both for pyrolysis and combustion processes. A general computer program was developed and the methods are compared with regard to their accuracy and the ease of interpretation of the kinetics of thermal decomposition. Activation energies of the

Mustafa Versan Kök; M. Reha Pamir

2000-01-01

339

Comparison of contact and radiant ablative pyrolysis of biomass  

Microsoft Academic Search

Ablation characterizes the phenomena occurring when a solid, submitted to a high external heat flux density, gives rise to solids, liquids and\\/or gases that can be rapidly and continuously eliminated. Ablation can be exploited for carrying out the fast pyrolysis of materials such as biomass. This paper describes and compares, on a fundamental point of view, two methods of biomass

Jacques Lédé

2003-01-01

340

Application of CFD to model fast pyrolysis of biomass  

Microsoft Academic Search

The article deals with the CFD modelling of fast pyrolysis of biomass in an Entrained Flow Reactor (EFR). The Lagrangian approach is adopted for the particle tracking, while the flow of the inert gas is treated with the standard Eulerian method for gases. The model includes the thermal degradation of biomass to char with simultaneous evolution of gases and tars

K. Papadikis; S. Gu; A. V. Bridgwater; H. Gerhauser

2009-01-01

341

Taxonomic discrimination of higher plants by pyrolysis mass spectrometry  

Microsoft Academic Search

Pyrolysis mass spectrometry (PyMS) is a rapid, simple, high-resolution analytical method based on thermal degradation of complex material in a vacuum and has been widely applied to the discrimination of closely related microbial strains. Leaf samples of six species and one variety of higher plants ( Rosa multiflora, R. multiflora var. platyphylla, Sedum kamtschaticum, S. takesimense, S. sarmentosum, Hepatica insularis,

S. W. Kim; S. H. Ban; H. J. Chung; D. W. Choi; P. S. Choi; O. J. Yoo; J. R. Liu

2004-01-01

342

Development and validation of a stability indicative HPLC-PDA method for kaurenoic acid in spray dried extracts of Sphagneticola trilobata (L.) Pruski, Asteraceae.  

PubMed

A gradient stability indicative HPLC-UV method was developed and validated for assay of the marker kaurenoic acid (KA) in spray dried extract of Sphagneticola trilobata (L.) Pruski. The marker, and another unidentified polar component, were separated on a Luna Phenomenex C(18) column (250×4.6 mm, 5 ?m) with mobile phase composed of acetonitrile:acidified water pH 3.0 with phosphoric acid, in a gradient run of 40 min; at a flow rate of 1.0 mL min(-1), 35 °C, using wavelengths of 210 and 338 nm. The method was linear over a KA concentration range of 4.5-30.0 ?g mL(-1), without interference of the herbal matrix on the linearity of the method. The RSD% values for the intra- and inter-day precision studies were <2.0 and <8.0% for inter-laboratorial study. The method showed excellent KA recovery (99.0%). The LOQ value was found to be 1.13 ?g mL(-1) and the method proved to be robust for small, deliberate changes in temperature and pH of the mobile phase with RSD%<2.5% for the KA assay. A forced degradation study of S. trilobata dried extract was conducted under conditions of visible light (1.200.000 l×h(-1)) and UV (200 Whm(-2)) irradiation, acid (0.5 mol L(-1) HCl, 30 min), basic (1 mol L(-1) NaOH, 2 h) and oxidative (30% H(2)O(2), 4h) hydrolysis, in order to develop a gradient stability-indicating LC-UV method for KA quantification, the selected marker, and also to detect the major polar components of the extract, under investigation. The KA contents remaining after these stress conditions were 72.3, 70.0, 97.6, 65.8 and 87.0%, respectively. The alkaline conditions resulted in higher degradation for the unknown polar components of the extract, without interference of supplementary peaks at the retention time of the KA. This method can be used for the KA assay and qualitative analysis of polar components in stability study of spray dried extracts of S. trilobata, for subsequent use in the quality control of dosage forms. PMID:23158359

Fucina, Giovana; Block, Luciana Catia; Baccarin, Thaisa; Ribeiro, Thiago Ruiz Gutierrez; Quintão, Nara Lins Meira; Filho, Valdir Cechinel; Silva, Ruth Meri Lucinda; Bresolin, Tania Mari Bellé

2012-11-15

343

Nasal spray flu vaccine (image)  

MedlinePLUS

The flu vaccine can also be administered as a nasal spray instead of the usual injection method. It is an ... 49 who want to be protected from the flu virus. Unlike the regular vaccine, it is a live virus. Therefore, it is ...

344

Pyrolysis-combustion 14C dating of soil organic matter  

USGS Publications Warehouse

Radiocarbon (14C) dating of total soil organic matter (SOM) often yields results inconsistent with the stratigraphic sequence. The onerous chemical extractions for SOM fractions do not always produce satisfactory 14C dates. In an effort to develop an alternative method, the pyrolysis-combustion technique was investigated to partition SOM into pyrolysis volatile (Py-V) and pyrolysis residue (Py-R) fractions. The Py-V fractions obtained from a thick glacigenic loess succession in Illinois yielded 14C dates much younger but more reasonable than the counterpart Py-R fractions for the soil residence time. Carbon isotopic composition (??13C) was heavier in the Py-V fractions, suggesting a greater abundance of carbohydrate- and protein-related constituents, and ??13C was lighter in the Py-R fractions, suggesting more lignin- and lipid-related constituents. The combination of 14C dates and ??13C values indicates that the Py-V fractions are less biodegradation resistant and the Py-R fractions are more biodegradation resistant. The pyrolysis-combustion method provides a less cumbersome approach for 14C dating of SOM fractions. With further study, this method may become a useful tool for analyzing unlithified terrestrial sediments when macrofossils are absent. ?? 2003 University of Washington. Published by Elsevier Inc. All rights reserved.

Wang, H.; Hackley, K.C.; Panno, S.V.; Coleman, D.D.; Liu, J.C.-L.; Brown, J.

2003-01-01

345

Free Radicals in Superfluid Liquid Helium Nanodroplets: A Pyrolysis Source for the Production of Propargyl Radical  

E-print Network

An effusive pyrolysis source is described for generating a continuous beam of radicals under conditions appropriate for the helium droplet pick-up method. Rotationally resolved spectra are reported for the $\

Küpper, J; Miller, R E; K\\"upper, Jochen; Merritt, Jeremy M.; Miller, Roger E.

2002-01-01

346

Catalytic fast pyrolysis of lignin over mesoporous Y zeolite using Py-GC/MS.  

PubMed

The catalytic pyrolysis of lignin was carried out at 500 degrees C using pyrolysis gas chromatography/mass spectrometry. In-situ vapor cracking method, in which the vapor-phase products from the noncatalytic pyrolysis step were catalytically upgraded in the second step, was used. Mesoporous Y zeolite, which was synthesized from commercial zeolite Y (CBV720) using the pseudomorphic synthesis method, was used for the catalytic pyrolysis of lignin for the first time. Further, a representative mesoporous material, Al-MCM-41, was applied for the catalytic pyrolysis of lignin. The main products of the non-catalytic pyrolysis of lignin were phenolic compounds because lignin mainly comprises phenylpropane units. Catalytic upgrading of the non-catalytic pyrolysis products resulted in increased yields of low-molecular-mass phenolics, mono aromatics, and poly aromatic hydrocarbons (PAHs). The production of mono aromatics and PAHs was enhanced remarkably when the more acidic mesoporous Y zeolite was used. Conversely, the yield-of alkoxy phenolics was higher when the less acidic Al-MCM-41 was used. With increasing mesoporous Y/lignin ratio, the yield of total phenolics decreased and that of light phenolics increased. The yields of mono aromatics and PAHs increased sharply with increasing mesoporous Y/lignin ratio. PMID:23763139

Lee, Hyung Won; Kim, Tae Hwan; Park, Sung Hoon; Jeon, Jong-Ki; Suh, Dong Jin; Park, Young-Kwon

2013-04-01

347

Combustion, pyrolysis, gasification, and liquefaction of biomass  

SciTech Connect

All the products now obtained from oil can be provided by thermal conversion of the solid fuels biomass and coal. As a feedstock, biomass has many advantages over coal and has the potential to supply up to 20% of US energy by the year 2000 and significant amounts of energy for other countries. However, it is imperative that in producing biomass for energy we practice careful land use. Combustion is the simplest method of producing heat from biomass, using either the traditional fixed-bed combustion on a grate or the fluidized-bed and suspended combustion techniques now being developed. Pyrolysis of biomass is a particularly attractive process if all three products - gas, wood tars, and charcoal - can be used. Gasification of biomass with air is perhaps the most flexible and best-developed process for conversion of biomass to fuel today, yielding a low energy gas that can be burned in existing gas/oil boilers or in engines. Oxygen gasification yields a gas with higher energy content that can be used in pipelines or to fire turbines. In addition, this gas can be used for producing methanol, ammonia, or gasoline by indirect liquefaction. Fast pyrolysis of biomass produces a gas rich in ethylene that can be used to make alcohols or gasoline. Finally, treatment of biomass with high pressure hydrogen can yield liquid fuels through direct liquefaction.

Reed, T.B.

1980-09-01

348

Combustion, pyrolysis, gasification, and liquefaction of biomas  

NASA Astrophysics Data System (ADS)

The advantages of biomass as a feedstock are examined and biomass conversion techniques are described. Combustion is the simplest method of producing heat from biomass, using either the traditional fixed bed combustion on a grate or the fluidized bed and suspended combustion techniques now being developed. Pyrolysis of biomass is a particularly attractive process if all three products gas, wood tars, and charcoal can be used. Gasification of biomass with air is perhaps the most flexible and best developed process for conversion of biomass to fuel, yielding a low energy gas that can be burned in existing gas/oil boilers or in engines. Oxygen gasification yields a gas with higher energy content that can be used in pipelines or to fire turbines. In addition, this gas can be used for producing methanol, ammonia, or gasoline by indirect liquefaction. Fast pyrolysis of biomass produces a gas rich in ethylene that can be used to make alcohols or gasoline. Finally, treatment of biomass with high pressure hydrogen can yield liquid fuels through direct liquefaction.

Reed, T. B.

1980-09-01

349

Effect of Spray Parameters on the Corrosion Behavior of HVOF Sprayed WC-Co-Cr Coatings  

NASA Astrophysics Data System (ADS)

WC-10Co-4Cr cermet coatings were deposited on the substrate of AISI 1045 steel by using high-velocity oxygen-fuel (HVOF) thermal spraying process. The Taguchi method including the signal-to-noise (S/N) ratio and the analysis of variance (ANOVA) was employed to optimize the porosity and, in turn, the corrosion resistance of the coatings. The spray parameters evaluated in this study were spray distance, oxygen flow, and kerosene flow. The results indicated that the important sequence of spray parameters on the porosity of the coatings was spray distance > oxygen flow > kerosene flow, and the spray distance was the only significant factor. The optimum spraying condition was 300 mm for the spray distance, 1900 scfh for the oxygen flow, and 6.0 gph for the kerosene flow. The results showed the significant influence of the microstructure on the corrosion resistance of the coatings. Potentiodynamic polarization and electrochemical impendence spectroscopy (EIS) results showed that the WC-10Co-4Cr cermet coating obtained by the optimum spraying condition with the lowest porosity exhibits the best corrosion resistance and seems to be an alternative to hard chromium coating.

Hong, Sheng; Wu, Yuping; Zheng, Yugui; Wang, Bo; Gao, Wenwen; Li, Gaiye; Ying, Guobing; Lin, Jinran

2014-04-01

350

Microstructural and macroscopic properties of cold sprayed copper coatings  

NASA Astrophysics Data System (ADS)

Cold spraying is a coating technique in which the formation of dense, tightly bonded coatings occurs only due to the kinetic energy of high velocity particles of the spray powder. These particles are still in the solid state as they impinge on the substrate. This study correlates optimized deposition parameters with the corresponding microstructure as well as mechanical and conductive behavior of cold sprayed copper coatings in order to explain possible bonding mechanisms. In addition, the performance of cold sprayed copper coatings is compared to that of cold rolled copper and to coatings prepared by thermal spray methods.

Borchers, C.; Gärtner, F.; Stoltenhoff, T.; Assadi, H.; Kreye, H.

2003-06-01

351

Pyrolysis of low-density polyethylene using synthetic catalysts produced from fly ash  

Microsoft Academic Search

Catalytic pyrolysis of low-density polyethylene (LDPE) was investigated using various fly ash-derived silica–alumina catalysts\\u000a (FSAs). FSAs were prepared by a simple activation method that basically includes NaOH treatment of fly ash by a fusion method,\\u000a followed by an aging process. A series of LDPE pyrolysis experiments was conducted and the catalytic performance of FSAs was\\u000a assessed in terms of the

Jeong-Geol Na; Byung-Hwan Jeong; Soo Hyun Chung; Seong-Soo Kim

2006-01-01

352

Plasma-Sprayed Coatings on Porous Surfaces  

NASA Technical Reports Server (NTRS)

Need for combining benefits of duplex thermal-barrier coatings with film cooling on gas-turbine vanes and blades stimulated development of improved method for plasma spraying these coatings. Method reduces blocking of holes by plasma-sprayed material and at same time reduces base-metal oxidation during coating operation. Features provide potential for increased engine efficiency and power, reduced fuel consumption, use of less costly materials or construction procedures, and extended life and durability.

Leibert, C. H.

1986-01-01

353

The effect of online catalytic pyrolysis on the yield of light liquid products  

NASA Astrophysics Data System (ADS)

Hydro-catalytic pyrolysis on Yunnan lignite were studied in a fixed bed to determine their effects on high-value raw materials, such as BTX, PCX and lower naphthalene, in liquid products. Ni and Mo were chosen as active pyrolysis centers through thermogravimetry, after which their catalytic effects were analyzed in a fixed bed. The results showed that different concentrations of impregnated Ni and Mo solution can significantly increase the yield of high-value products and enable catalyst separating and recycling with this method of online catalytic pyrolysis.

Zhao, Gangwei

2014-06-01

354

Pyrolysis of large wood samples  

Microsoft Academic Search

The kinetics of pyrolysis of large wood samples--up to 27 mm--has been studied by isothermal thermogravimetric analysis. Rate of weight loss can be represented by a first order Arrhenius-type equation, with an activation energy of 125 kJ\\/mole. The temperature inside the wood sample is given by integration of the Fourier law, in which the thermal diffusivity is temperature- and conversion-dependent.

P. Belleville; R. Capart; M. Gelus

1984-01-01

355

Modeling thermally thick pyrolysis of wood  

Microsoft Academic Search

A general model of the pyrolysis of a wood slab is presented and validated with a set of heat release data. The model is applied to particle half-thicknesses from 5?m to 5cm, temperatures from 800 to 2000K, and moisture contents from 0% to 30%. Internal temperatures, pyrolysis rates and yields of tar, hydrocarbons and char are presented. Four pyrolysis regimes

Kenneth M. Bryden; Kenneth W. Ragland; Christopher J. Rutland

2002-01-01

356

Development and validation of an RP-HPLC method to quantitate acyclovir in cross-linked chitosan microspheres produced by spray drying.  

PubMed

An accurate, simple, reproducible, and sensitive liquid chromatographic method is developed and validated to quantitate acyclovir (ACV) in cross-linked chitosan microspheres produced by spray drying. The analysis is carried out using a reversed-phase C18 column with UV-vis detection at 254 nm. The mobile phase is diluted with pure water and acetonitrile (95:5 v/v) at a flow-rate of 0.8 mL/min. The parameters used in the validation process are: linearity, range, quantitation limit, detection limit, accuracy, specificity precision, and ruggedness. The retention time of acyclovir is approximately 3.5 min with symmetrical peaks. The linearity in the range of 1-10 microg/mL presents a correlation coefficient of 0.9999. The chitosan and the tripolyphosphate in the formulation do not interfere with the analysis, and the recovery is quantitative. Results are satisfactory, and the method proves to be suitable to quantitate ACV in cross-linked chitosan microspheres. PMID:18647469

Stulzer, Hellen K; Tagliari, Monika Piazzon; Murakami, Fábio S; Silva, Marcos A S; Laranjeira, Mauro C M

2008-07-01

357

Effect of solution concentration on splat formation and coating microstructure using the solution precursor plasma spray process  

Microsoft Academic Search

The Solution Precursor Plasma Spray (SPPS) process had been successfully used to deposit 7YSZ thermal barrier coatings. In this research, the effects of solution precursor concentration on 7YSZ splat formation and coating microstructure are studied. With increasing solution concentration, solution viscosity increases and surface tension decreases. Solution concentration has no effect on precursor pyrolysis and crystallization temperatures. The average atomized

Dianying Chen; Eric H. Jordan; Maurice Gell

2008-01-01

358

Chemical characterization of pyrolysis liquids of wood-based composites and evaluation of their bio-efficiency  

Microsoft Academic Search

Pyrolysis of wood and wood-based wastes is considered to be one of the promising methods of supplying charcoal as solid material and liquids containing a number of valuable chemicals. In this study, we characterized the chemical components in the liquids from pyrolysis of solid wood and wood-based composites such as particleboard, plywood and medium density fiberboard (MDF) with phenol or

Tasuku Nakai; S. Nami Kartal; Toshimitsu Hata; Yuji Imamura

2007-01-01

359

PRODUCTION OF MULTI-WALL CARBON NANOTUBES BY MEANS OF FLUIDIZED BED PYROLYSIS OF VIRGIN OR RECYCLED POLYMERS  

E-print Network

to a new method for MWCNT production by means of a continuous pyrolysis process of virgin or recycled on the market even when the starting materials were polymers coming from post-consumers waste collectionPRODUCTION OF MULTI-WALL CARBON NANOTUBES BY MEANS OF FLUIDIZED BED PYROLYSIS OF VIRGIN OR RECYCLED

Paris-Sud XI, Université de

360

Kinetics and mechanisms of pyrolysis of polyborosilazanes to thermally stable amorphous and crystalline states by a novel synthesis route  

Microsoft Academic Search

A new type of SiBCN ceramic is being investigated and considered for a variety of high temperature applications. SiBCN ceramics have been produced by various synthesis methods in different monomer systems and subsequent pyrolysis processes at different temperatures. The final ceramic composition and structure are significantly affected by the selection of the polymer precursor material and the pyrolysis conditions. Although

Jongsang Lee

2004-01-01

361

Pyrolysis process for producing fuel gas  

NASA Technical Reports Server (NTRS)

Solid waste resource recovery in space is effected by pyrolysis processing, to produce light gases as the main products (CH.sub.4, H.sub.2, CO.sub.2, CO, H.sub.2O, NH.sub.3) and a reactive carbon-rich char as the main byproduct. Significant amounts of liquid products are formed under less severe pyrolysis conditions, and are cracked almost completely to gases as the temperature is raised. A primary pyrolysis model for the composite mixture is based on an existing model for whole biomass materials, and an artificial neural network models the changes in gas composition with the severity of pyrolysis conditions.

Serio, Michael A. (Inventor); Kroo, Erik (Inventor); Wojtowicz, Marek A. (Inventor); Suuberg, Eric M. (Inventor)

2007-01-01

362

Pyrolysis processing for solid waste resource recovery  

NASA Technical Reports Server (NTRS)

Solid waste resource recovery in space is effected by pyrolysis processing, to produce light gases as the main products (CH.sub.4, H.sub.2, CO.sub.2, CO, H.sub.2O, NH.sub.3) and a reactive carbon-rich char as the main byproduct. Significant amounts of liquid products are formed under less severe pyrolysis conditions, and are cracked almost completely to gases as the temperature is raised. A primary pyrolysis model for the composite mixture is based on an existing model for whole biomass materials, and an artificial neural network models the changes in gas composition with the severity of pyrolysis conditions.

Serio, Michael A. (Inventor); Kroo, Erik (Inventor); Wojtowicz, Marek A. (Inventor); Suuberg, Eric M. (Inventor)

2007-01-01

363

Bear Spray Safety Program  

USGS Publications Warehouse

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.

Blome, C.D.; Kuzniar, R.L.

2009-01-01

364

Pyrolysis characteristics and kinetics of aquatic biomass using thermogravimetric analyzer.  

PubMed

The differences in pyrolysis process of three species of aquatic biomass (microalgae, macroalgae and duckweed) were investigated by thermogravimetric analysis (TGA). Three stages were observed during the pyrolysis process and the main decomposition stage could be divided further into three zones. The pyrolysis characteristics of various biomasses were different at each zone, which could be attributed to the differences in their components. A stepwise procedure based on iso-conversional and master-plots methods was used for the kinetic and mechanism analysis of the main decomposition stage. The calculation results based on the kinetic model was in good agreement with the experimental data of weight loss, and each biomass had an increasing activation energy of 118.35-156.13 kJ/mol, 171.85-186.46 kJ/mol and 258.51-268.71 kJ/mol in zone 1, 2 and 3, respectively. This study compares the pyrolysis behavior of various aquatic biomasses and provides basis for further applications of the biomass thermochemical conversion. PMID:24768943

Wu, Kejing; Liu, Ji; Wu, Yulong; Chen, Yu; Li, Qinghai; Xiao, Xin; Yang, Mingde

2014-07-01

365

Fate of forms of arsenic in Yima coal during pyrolysis  

SciTech Connect

Forms of arsenic in a Chinese bituminous coal, Yima, and their transformation behaviors during coal pyrolysis were investigated. The chemical leaching method was used to characterize the forms of arsenic in the raw coal and the chars. The effect of minerals on arsenic release was also studied. It was found that about 72% arsenic in YM coal is bound to sulfide species; 16% to sulfates, phosphates, or oxides; 10% to organic species; and 2% to aluminosilicates. The organic-bound arsenic is the most releasable, while the aluminosilicates-bound arsenic is the least releasable. Aluminosilicates inhibit arsenic release due to the formation of aluminosilicates-bound arsenic during pyrolysis. Sulfides, sulfates, phosphates, or oxides may also restrain arsenic release. Carbonates and ion exchangeable minerals in Yima coal do not show any significant influence on the release of arsenic during coal pyrolysis. Secondary reactions between arsenic and the coal matrix should exist, as evidenced by significant increase in organic-bound arsenic in chars obtained from pyrolysis in a temperature range of 300-700{sup o}C. 18 refs., 5 figs., 5 tabs.

Ruiqing Liu; Jianli Yang; Yong Xiao; Zhenyu Liu [Chinese Academy of Sciences, Taiyuan (China). State Key Laboratory of Coal Conversion

2009-04-15

366

Dihydroergotamine Injection and Nasal Spray  

MedlinePLUS

Migranal® Nasal Spray ... inject subcutaneously (under the skin) and as a spray to be used in the nose. It is ... that you know how to use the nasal spray or administer the injection correctly. After that, you ...

367

Comparison of petroleum generation kinetics by isothermal hydrous and nonisothermal open-system pyrolysis  

USGS Publications Warehouse

This study compares kinetic parameters determined by open-system pyrolysis and hydrous pyrolysis using aliquots of source rocks containing different kerogen types. Kinetic parameters derived from these two pyrolysis methods not only differ in the conditions employed and products generated, but also in the derivation of the kinetic parameters (i.e., isothermal linear regression and non-isothermal nonlinear regression). Results of this comparative study show that there is no correlation between kinetic parameters derived from hydrous pyrolysis and open-system pyrolysis. Hydrous-pyrolysis kinetic parameters determine narrow oil windows that occur over a wide range of temperatures and depths depending in part on the organic-sulfur content of the original kerogen. Conversely, open-system kinetic parameters determine broad oil windows that show no significant differences with kerogen types or their organic-sulfur contents. Comparisons of the kinetic parameters in a hypothetical thermal-burial history (2.5 ??C/my) show open-system kinetic parameters significantly underestimate the extent and timing of oil generation for Type-US kerogen and significantly overestimate the extent and timing of petroleum formation for Type-I kerogen compared to hydrous pyrolysis kinetic parameters. These hypothetical differences determined by the kinetic parameters are supported by natural thermal-burial histories for the Naokelekan source rock (Type-IIS kerogen) in the Zagros basin of Iraq and for the Green River Formation (Type-I kerogen) in the Uinta basin of Utah. Differences in extent and timing of oil generation determined by open-system pyrolysis and hydrous pyrolysis can be attributed to the former not adequately simulating natural oil generation conditions, products, and mechanisms.

Lewan, M. D.; Ruble, T. E.

2002-01-01

368

Turbulence modulation and dense-spray structure  

NASA Astrophysics Data System (ADS)

A theoretical and experimental study of phenomena related to dense sprays is described. Two aspects of dense sprays are being considered: effects of turbulence modulation, which is the direct effect of particle (drop) motion on the turbulence properties of multiphase flows; and the structure and mixing properties of the dense-spray region of pressure atomized sprays. Turbulence modulation is being studied by considering spherical monodisperse glass particles falling in a stagnant water bath, where effects of turbulence modulation are responsible for the entire turbulence field. Measurements involve phase velocities and temporal and spatial correlations and spectra of the continuous phase velocities using a two-point phase-discriminating laser Doppler anemometer. Flow properties are being analyzed using stochastic methods: assuming linear superposition of randomly arriving particle wakes (Poisson statistics) for liquid phase properties; and random-walk calculations based on statistical time-series methods for particle properties.

Parthasarathy, R. N.; Ruff, G. A.; Faeth, G. M.

1988-08-01

369

Modeling the impact of shrinkage on the pyrolysis of dry biomass  

Microsoft Academic Search

A new method for modeling shrinkage of a biomass particle is presented and validated in a detailed wood pyrolysis model. This model is applied to particle half-thicknesses ranging from 5?m to 2cm, temperatures from 800 to 2000K, and shrinkage factors of 1.0–0.4. Internal temperatures, pyrolysis rates, and yields of tar, light hydrocarbons and char are presented. Based on the results

Mathew J Hagge; Kenneth M Bryden

2002-01-01

370

Effect of pyrolysis temperature and air flow on toxicity of gases from a polycarbonate polymer  

NASA Technical Reports Server (NTRS)

A polycarbonate polymer was evaluated for toxicity of pyrolysis gases generated at various temperatures without forced air flow and with 1 L/min air flow, using the toxicity screening test method developed at the University of San Francisco. Time to various animal responses decreased with increasing pyrolysis temperature over the range from 500 C to 800 C. There appeared to be no significant toxic effects at 400 C and lower temperatures.

Hilado, C. J.; Brick, V. E.; Brauer, D. P.

1978-01-01

371

Thermogravimetric analysis and pyrolysis of waste mixtures of paint and tar slag  

Microsoft Academic Search

We describe thermogravimetric analyses and pyrolysis kinetic studies carried out on hazardous waste mixtures of tar slag,\\u000a paint slag, paper, sodium sulfate and calcium oxide. Both thermogravimetric (TG) and differential thermogravimetric (DTG)\\u000a profiles were measured by a thermogravimetric analyzer at different final temperatures, particle sizes and heating rates.\\u000a Pyrolysis kinetic parameters were calculated by the Coats-Redfern method. Influences of particle

Ling Tao; Guang-Bo Zhao; Juan Qian; Yu-Kun Qin

2009-01-01

372

Hydrous pyrolysis\\/oxidation: in-ground thermal destruction of organic contaminants  

Microsoft Academic Search

Experimental work with organic solvents at Lawrence Livermore National Laboratory has suggested that in situ thermal oxidation of these compounds via hydrous pyrolysis forms the basis for a whole new remediation method, called hydrous pyrolysis oxidation. Preliminary results of hydrothermal oxidation using both dissolved 0â gas and mineral oxidants present naturally in soils (e.g., MnOâ) demonstrate that TCE, TCA, and

K. G. Knauss; R. D. Aines; M. J. Dibley; R. N. Leif; D. A. Mew

1997-01-01

373

Synthesis of long YBCO, BSCCO HTSC coatings by gas-detonation spraying technology and gas-flame method of crystallization  

SciTech Connect

This technology allows for the production of long HTSC coatings for the manufacture of tapes and wires as well as shields and antennas. Gas-thermal methods allow the authors to obtain films (10 -100 {mu}m) on non-oriented substrates of arbitrary shape. A gas-flame method of crystallization allows them to obtain dense coatings with high adhesion. These HTSC composites are easily workable to shape into the desired geometry. The critical temperature of the coatings corresponds to that of the starting HTSC ceramics; T{sub c} = 82 K for YBCO and T{sub c} = 81 K, T{sub c} = 103 K for BSCCO. Values of j{sub c} =2*10{sup 3} A/cm{sup 2} at T = 77 K, H = 0 have been obtained. The proposed method has high productivity and low cost.

Bykov, Y. [Univ. of Toledo, OH (United States); Grigor`eva, A.V.; Shkut, V.A.

1997-06-01

374

Application methods and evaluations of ultra-low-volume sprays for controlling the bollworm, tobacco budworm and boll weevil  

E-print Network

with a + hoXXos-cone soceke tip (Pigere 8) ~ The dosages were deiivered on ths encioxxnR yisnt in 8uantities x'caging from G. i to i mi. Bc@1 weeviie were used es test insects with this method ~ Piente were txeatel at different dosages an... with a + hoXXos-cone soceke tip (Pigere 8) ~ The dosages were deiivered on ths encioxxnR yisnt in 8uantities x'caging from G. i to i mi. Bc@1 weeviie were used es test insects with this method ~ Piente were txeatel at different dosages an...

Nemec, Stanley Joseph

2012-06-07

375

Current problems in plasma spray processing  

Microsoft Academic Search

This article summarizes eight contributions from a thermal spray conference that was held in late 1991 at Brookhaven National\\u000a Laboratory, Upton, Long Island, New York. Plasma spray processing is discussed in terms of plasma-particle interactions, deposit\\u000a formation dynamics, thermal properties of thermal barrier coatings, mechanical properties of coatings, feedstock materials,\\u000a porosity, manufacture of intermetallic coatings, and synchrotron X-ray microtomographic methods

C. C. Berndt; W. Brindley; A. N. Goland; H. Herman; D. L. Houck; K. Jones; R. A. Miller; R. Neiser; W. Riggs; S. Sampath; M. Smith; P. Spanne

1992-01-01

376

SPRAY CALCINATION REACTOR  

Microsoft Academic Search

A spray calcination reactor for calcining reprocessin- g waste solutions ; is described. Coaxial within the outer shell of the reactor is a shorter inner ; shell having heated walls and with open regions above and below. When the ; solution is sprayed into the irner shell droplets are entrained by a current of ; gas that moves downwardly within

Johnson

1963-01-01

377

Nicotine Nasal Spray  

MedlinePLUS

... how to decrease your nicotine dose.Nicotine nasal spray may be habit-forming. Do not use a larger dose, use it more often, or use it for a longer period of time than prescribed by your doctor.To use the nasal spray, follow these directions: Wash your hands. Gently blow ...

378

Plasma-Sprayed Coatings  

Microsoft Academic Search

Plasma spraying is one way to apply protective coatings. The hot, high-speed flame of a plasma gun can melt a powder of almost any ceramic or metal and spray it to form a coating for protection against corrosion, wear or high temperature. The technique carries much less risk of degrading the coating and substrate than many other high-temperature processes do,

Herbert Herman

1988-01-01

379

Fentanyl Sublingual Spray  

MedlinePLUS

Fentanyl sublingual spray is used to treat breakthrough pain (sudden episodes of pain that occur despite round the clock treatment with ... Fentanyl comes as a solution (liquid) to spray sublingually ( under the ... breakthrough pain, but not more often than directed by your doctor. Follow ...

380

Applications of sprayed coatings  

Microsoft Academic Search

Service demands of the coating properties of sprayed coatings are classified as: preventing, fretting, wear, and corrosion; controlled abradability; and thermal barrier. Developments in both coating techniques and coating materials which have allowed production of coatings which match the performance demands are considered. Applications of sprayed coatings in aircraft components are discussed. Bibtex entry for this abstract Preferred format for

H. D. Steffens; M. Malik

1980-01-01

381

Flash pyrolysis products from beech wood  

SciTech Connect

Flash pyrolysis products from beech wood obtained in an original pyrolysis apparatus were analyzed. The analytical procedure is described, and the composition of pyrolytic oil presented with more than 50 compounds. Comparison of pyrolytic products of cellulose, hemicellulose, and wood indicates the origin of each product. 19 references.

Beaumont, O.

1985-04-01

382

General kinetic model of oil shale pyrolysis  

Microsoft Academic Search

A mathematical model for pyrolysis of Green River oil shale is developed from previous experiments on oil, water, and gas evolution and oil cracking over a wide range of pyrolysis conditions. Reactions included are evolution of 5 gas species, oil, and water from kerogen, clay dehydration, oil coking and cracking, and evolution of Hâ and CHâ from char. Oil is

Alan K. Burnham; Robert L. Braun

1985-01-01

383

Pyrolysis of waste plastic crusts of televisions  

Microsoft Academic Search

The disposal of waste plastic crusts of televisions is an issue that is gaining increasing interest around the world. In this investigation, the pyrolysis and catalytic cracking of the waste television crusts mainly composed of acrylonitrile–butadiene–styrene copolymer was studied. Thermogravimetric analysis was used for initial characterization of the pyrolysis of the waste plastic, but most of the investigations were carried

Xinmin Liu; Zhen Wang; Dongyan Xu; Qingjie Guo

2012-01-01

384

Pyrolysis characteristics of biomass and biomass components  

Microsoft Academic Search

Biomass pyrolysis studies were conducted using both a thermogravimetric analyser and a packed-bed pyrolyser. Each kind of biomass has a characteristic pyrolysis behaviour which is explained based on its individual component characteristics. Studies on isolated biomass components as well as synthetic biomass show that the interactions among the components are not of as much significance as the composition of the

K. Raveendran; Anuradda Ganesh; Kartic C. Khilar

1996-01-01

385

Technological parameters of pyrolysis of waste polytetrafluoroethylene  

Microsoft Academic Search

The results of the pyrolysis of waste polytetrafluoroethylene (PTFE) to the useful compounds: tetrafluoroethylene, hexafluoropropylene, octafluorocyclobutane and heavy ends (mainly 1- and 2-octafluorobutylene) are presented. The studies were carried out in a two-stage reactor, where the second stage also consisted of two sections. The influence of temperature, pressure, nitrogen flow rate, PTFE feed rate, and residence time of the pyrolysis

Egbert Meissner; Agnieszka Wróblewska; Eugeniusz Milchert

2004-01-01

386

Early products of pyrolysis of wood  

SciTech Connect

The authors are studying the first stages in pyrolysis of wood and other cellulosic materials as part of a study of the chemistry of smoldering or low-temperature combustion. In the latter processes both oxidative and non-oxidative pyrolysis occur. This paper describes an investigation of the first volatile products of pyrolysis of wood and they believe that many of the conclusions regarding the first pyrolysis reactions at low temperatures are applicable also to higher temperature treatments of wood such as are utilized in liquefaction processes. The aim was primarily to determine the relative rates and modes of pyrolysis of the three major constituents of wood (viz. cellulose, hemicelluloses and lignin) from their chemically intact situation in whole wood.

De Groot, W.F.; Pan, W.P.; Rahman, M.D.; Richards, G.N.

1987-04-01

387

A simplified model of aerosol removal by containment sprays  

SciTech Connect

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.

Powers, D.A. (Sandia National Labs., Albuquerque, NM (United States)); Burson, S.B. (Nuclear Regulatory Commission, Washington, DC (United States). Div. of Safety Issue Resolution)

1993-06-01

388

COANDA-ASSISTED SPRAY MANIPULATION IMPLEMENTATION TO PLASMA SPRAY  

E-print Network

on a plasma spray gun for small angle vectoring. Three-dimensional PIV was used to determine the eect of highCOANDA-ASSISTED SPRAY MANIPULATION IMPLEMENTATION TO PLASMA SPRAY by Katie E. Mabey A thesis Manipulation Implementation to Plasma Spray by Katie E. Mabey, Master of Science Utah State University, 2011

Smith, Barton L.

389

Pyrolysis of coal  

DOEpatents

A method for mild gasification of crushed coal in a single vertical elongated reaction vessel providing a fluidized bed reaction zone, a freeboard reaction zone, and an entrained reaction zone within the single vessel. Feed coal and gas may be fed separately to each of these reaction zones to provide different reaction temperatures and conditions in each reaction zone. The reactor and process of this invention provides for the complete utilization of a coal supply for gasification including utilization of caking and non-caking or agglomerating feeds in the same reactor. The products may be adjusted to provide significantly greater product economic value, especially with respect to desired production of char having high surface area.

Babu, Suresh P. (Willow Springs, IL); Bair, Wilford G. (Morton Grove, IL)

1992-01-01

390

A study of the physical and chemical stability of spray dried aluminum hydroxycarbonate and of drying methods for aluminum hydroxycarbonate gel: Part~I. The physical and chemical stability of spray dried aluminum hydroxycarbonate gel. Part~II. Drying methods for aluminum hydroxycarbonate gel  

Microsoft Academic Search

Part I. The physical and chemical stability of spray dried aluminum hydroxycarbonate gel. The physical and chemical stability of amorphous spray dried aluminum hydroxycarbonate gel (SDAHC) was studied at five relative humidities: 0%, 11%, 54%, 84%, and 100%. The moisture content of the SDAHC directly related to the relative humidity. The samples with the highest moisture content showed the greatest

Kim Elaine Hancock

1994-01-01

391

Assessment of the chemical changes during storage of phenol-formaldehyde resins pyrolysis gas chromatography mass spectrometry, inverse gas chromatography and Fourier transform infra red methods.  

PubMed

The chemical changes occurring in the phenol-formaldehyde resins (resol and novolac type) during their storage were investigated. In this paper the FT-IR, py-GCMS and inverse gas chromatography methods were applied for assessment of the changes occurring during storage of the phenolic resins. We have found that during storage some examined resins occurred partial curing. The results from all techniques applied are consistent. Py-GCMS is useful technique for screening the storage processes but IGC seems to be most sensitive one. PMID:25092596

Strzemiecka, B; Voelkel, A; Zi?ba-Palus, J; Lachowicz, T

2014-09-12

392

Investigation on thermochemical behavior of co-pyrolysis between oil-palm solid wastes and paper sludge.  

PubMed

The pyrolysis characteristics of oil-palm solid wastes, paper sludge and their blends were studied via thermogravimetric analysis. Blends ranging from 10 wt.% to 90 wt.% on dosage ratio were prepared to investigate their co-pyrolysis behavior and kinetics. There was a synergistic interaction at low temperature during co-pyrolysis between oil-palm solid wastes and paper sludge. The synergistic interaction would improve thermochemical pyrolysis reactivity of the blends, which could be attributed to the hydrogenation role and the potential mineral catalytic effects on paper sludge pyrolysis. The value of average activation energy obtained by Starink and Friedmen methods did not gradually decline with the increasing proportion of oil-palm solid wastes in the blends. The lowest average activation energy was achieved when the percentage of oil-palm solid wastes was 70%, which was 152 kJ/mol by Starink and 149 kJ/mol by Friedmen, respectively. PMID:24935005

Lin, Yousheng; Ma, Xiaoqian; Yu, Zhaosheng; Cao, Yawen

2014-08-01

393

Toxicity of pyrolysis products: Influence of experimental conditions - The MSTL/UT and NASA/JSC Procedures  

NASA Technical Reports Server (NTRS)

Ten sample materials of various polymeric composition were evaluated for toxicity of pyrolysis products utilizing two significantly different experimental methods, the MSTL/UT and NASA/JSC Procedures. A comparison of the LD(50) values obtained by the two methods for these ten samples did not yield a significant correlation. However, when the samples were ranked in order of increasing toxicity by each method independently, a comparison of their rank order toxicity improved the correlation. Because of interlaboratory variations in pyrolysis/combustion test procedures, it is suggested a series of standard materials be adopted to facilitate interlaboratory comparisons of data on pyrolysis toxicity.

Lawrence, W. H.; Raje, R. R.; Singh, A. R.; Autian, J.

1978-01-01

394

European Market Study for BioOil (Pyrolysis Oil)  

E-print Network

-distance transportation advantages over raw biomass and wood pellets is BioOil from fast pyrolysis, or Pyrolysis OilEuropean Market Study for BioOil (Pyrolysis Oil) Dec 15, 2006 Doug Bradley President Climate Change of Contents Scope Executive Summary 1. Background 2. Pyrolysis Oil-Char Supply and Export Potential 2

395

Modelling and measurements of the pyrolysis of large wood particles  

Microsoft Academic Search

The influence from structural changes, heat transfer properties of dry wood and pyrolysis mechanism on the pyrolysis of large wood particles were studied. Measurements of temperature distribution and mass loss were performed on cylindrical samples of dry birch wood during pyrolysis in an inert atmosphere at 700°C. A model of wood pyrolysis was modified to include structural changes. Comparisons of

J Larfeldt; B Leckner; M. C Melaaen

2000-01-01

396

Life-cycle assessment of flash pyrolysis of wood waste  

Microsoft Academic Search

This work analyzes a process known as flash pyrolysis, which produces bio fuels using biomass for power generation. A life-cycle assessment of flash pyrolysis of wood waste was conducted to study whether a flash pyrolysis plant set up locally would be environmentally friendly. The results obtained show that the process of flash pyrolysis of wood waste is in fact environmentally

Z. W. Zhong; B. Song; M. B. M. Zaki

2010-01-01

397

CFD Study on the Application of Rotary Kiln in Pyrolysis  

Microsoft Academic Search

The pyrolysis of bulk feed requires the use of some alternative pyrolysis reactors other than the conventional fluidized bed reactors used in the fast pyrolysis of biomass. An indirect-fired rotary kiln was suggested to be a suitable choice subject to the need for a better thermal efficiency. An approach to utilize the Computational Fluid Dynamics (CFD) simulation and the pyrolysis

Ka-Leung Lam; Adetoyese O. Oyedun; Chi-Wai Hui

2011-01-01

398

Non-Isothermal Pyrolysis and Kinetics of Oil Shales  

Microsoft Academic Search

In this research, non-isothermal pyrolysis behavior and kinetics of three oil shales were studied by thermal analysis methods.\\u000a All the thermal effects were endothermic and no exothermic region was observed in DSC curves. When oil shales are heated in\\u000a nitrogen atmosphere in TG\\/DTG, two different mechanisms causing loss of mass were observed. The region between ambient temperature\\u000a and 500 K

M. V. Kök; M. R. Pamir

1999-01-01

399

Pyrolysis and gasification kinetics of Jordanian oil-shales  

Microsoft Academic Search

Two Jordanian oil-shale samples have been pyrolysed and gasified, non-isothermally, using a thermogravimetric analyser. The controlling parameters studied were the final temperature and influence of particle size as well as the heating rate employed during the process of thermal degradation of the oil-shale sample. The integral method was used in the analysis of weight-loss data to determine the pyrolysis and

J. O. Jaber; S. D. Probert

1999-01-01

400

Toxicity of pyrolysis gases from some synthetic polymers  

NASA Technical Reports Server (NTRS)

Nine samples of synthetic polymers were evaluated for toxicity of pyrolysis gases, using the toxicity screening test method developed at the University of San Francisco. The materials were polyoxymethylene, polyethylene (five samples), polypropylene, polymethyl methacrylate, and polystyrene. Of the five polyethylene samples, three contained known levels of chlorine. These test results were combined with earlier data to provide a comparison of 25 samples of synthetic polymers. Polyoxymethylene appeared to exhibit the greatest toxicity, and polystyrene the least toxicity, under these particular test conditions

Hilado, C. J.; Huttlinger, N. V.

1978-01-01

401

Electrochemically assisted pyrolysis of hardwoods  

SciTech Connect

This project explored the low-temperature, electrochemically assisted pyrolysis of lignocellulosic material to low-molecular-weight organic chemicals. Through the agency of low temperature AlCl{sub 3}-based molten salts, aspen hardwood flour was reacted in AlCl{sub 3}:NaCl, AlCl{sub 3}:NaCl:KCl, and AlCl{sub 3}:BPC (n-butylpyridinium chloride) media at temperatures from 30-220 C. A wide variety of water soluble products were formed comprising CO, CO{sub 2}, keto-alcohols and low molecular weight phenolic compounds as determined by GC and FTIR spectroscopy. The compounds represented about 32% by weight of the aspen wood flour. Owing to the narrow (2 volt) electrochemical window versus an Al reference electrode, neither the wood flour nor the reaction products manifested any electro-activity. Authentic samples of cellulose, hemicellulose, and Klason lignin were also subjected to low temperature pyrolysis. Only the hemicellulose reacted to give CO{sub 2} and keto-alcohols.

Koch, V.R.

1986-08-01

402

Effects of sea spray geoengineering  

NASA Astrophysics Data System (ADS)

Anthropogenic climate warming is leading to consideration of options for geoengineering to offset rising carbon dioxide levels. One potential technique involves injecting artificial sea spray into the atmosphere. The sea salt particles would affect Earth's radiation budget directly, by scattering incoming solar radiation, and indirectly, by acting as cloud condensation nuclei, which could lead to whiter clouds that reflect more radiation. However, the potential effects of this method, especially the direct effects, are not fully known. Partanen et al. studied the effects of artificial sea spray using climate model simulations. They found that outside of the most heavily clouded regions the direct effect of scattering of radiation was an important part of the total effect. They also examined the effect of particle size and found that decreasing the size of injected particles could improve the efficiency of the geoengineering technique.

Balcerak, Ernie

2012-03-01

403

Plasma Spray System  

NASA Technical Reports Server (NTRS)

Computer aided, fully-automatic TRW system sprays very hot plasma onto a turbine blade. Composed of gas into which metallic and ceramic powders have been injected, the plasma forms a two-layer coating which insulates the blade. Critical part of operation is controlling the thickness of the deposit which is measured in thousandths of an inch. This is accomplished by an optical detector which illuminates spots at various locations on the blade and determines thickness by measuring the light reflections. Optical sensor monitors spraying process until precise thickness is attained, then computer halts the spraying.

1980-01-01

404

High mass throughput particle generation using multiple nozzle spraying  

DOEpatents

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.

Pui, David Y. H. (Plymouth, MN); Chen, Da-Ren (Creve Coeur, MO)

2009-03-03

405

Electrical and optical properties of ultrasonically sprayed Al-doped zinc oxide thin films  

Microsoft Academic Search

Aluminium-doped ZnO (AZO) films were deposited by ultrasonic spray pyrolysis (USP) technique to investigate its potential application as antireflection coating and top contact layer for copper indium gallium diselenide (CIGS) based photovoltaic cells. The solution used to prepare AZO thin films contained 0.2M of zinc acetate and 0.2M of aluminium pentanedionate solutions in the order of 2, 3 and 4at.%

B. J. Babu; A. Maldonado; S. Velumani; R. Asomoza

2010-01-01

406

Sensing low concentrations of CO using flame-spray-made Pt\\/SnO 2 nanoparticles  

Microsoft Academic Search

Tin dioxide nanoparticles of different sizes and platinum doping contents were synthesized in one step using the flame spray\\u000a pyrolysis (FSP) technique. The particles were used to fabricate semiconducting gas sensors for low level CO detection, i.e.\\u000a with a CO gas concentration as low as 5 ppm in the absence and presence of water. Post treatment of the SnO2 nanoparticles was

L. Mädler; T. Sahm; A. Gurlo; J.-D. Grunwaldt; N. Barsan; U. Weimar; S. E. Pratsinis

2006-01-01

407

Spray Pyrolysed Cu2ZnSnS4 Solar Cell Using Cadmium Free Buffer Layer  

Microsoft Academic Search

Cu2ZnSnS4 (CZTS) thin film solar cells were fabricated using CZTS as absorber layer and In2S3 as buffer layer. Both of these layers were prepared by using chemical spray pyrolysis (CSP) technique. Since the resistance of the In2S3 buffer layer plays an important role in the performance parameters of the cell we have done excitu doping of In2S3 by using indium.

V. G. Rajeshmon; C. Sudha Kartha; K. P. Vijayakumar

2011-01-01

408

Photoluminescence studies on off-stoichiometric defects in sprayed CZTS thin films  

NASA Astrophysics Data System (ADS)

Photoluminescence (PL) technique was used for studying the defects in Copper Zinc Tin Sulphide (CZTS) thin films deposited by Chemical Spray Pyrolysis (CSP). Measurements were done on films prepared for different Cu:Zn:Sn:S ratios. An emission at 0.805 eV was monitored from 15 K to room temperature and activation energy was calculated. Excitation power dependent studies were done to analyze the type of transition.

Poornima, N.; Rajeshmon, V. G.; Kartha, C. Sudha; Vijayakumar, K. P.

2014-04-01

409

Spray deposited Nb 2 O 5 thin film electrodes for fabrication of dye sensitized solar cells  

Microsoft Academic Search

Nb2O5 thin film electrodes have been deposited on indium tin oxide substrates by spray pyrolysis technique. XRD analysis reveals\\u000a tetragonal phase of the film. Reticulated micro-fibrous surface morphology has been observed by scanning electron microscopy\\u000a and atomic force microscopy indicates closely packed crystallites. Film thickness found using a stylus profilometer is around\\u000a 26 nm. Transmittance spectra show the film to

M. Kovendhan; D. Paul Joseph; P. Manimuthu; S. Ganesan; S. Sambasivam; P. Maruthamuthu; S. Austin Suthanthiraraj; C. Venkateswaran; R. Mohan

2011-01-01

410

DEMONSTRATION OF SPLIT-FLOW VENTILATION AND RECIRCULATION AS FLOW-REDUCTION METHODS IN AN AIR FORCE PAINT SPRAY BOOTH - VOLUME II. APPENDICES D-J  

EPA Science Inventory

During a series of painting operations in a horizontal-flow paint spray booth at Travis AFB, CA, baseline concentrations of four classes of toxic airborne pollutants were measured at 24 locations across a plane immediately forward of the exhaust filters, in the exhaust duct, and ...

411

Development and evaluation of a method for the design of spray applications: aerial tebufenozide applications to control the eastern spruce budworm, Choristoneura fumiferana (Clem.)  

Microsoft Academic Search

A novel approach to the design of insecticide spray applications was developed and evaluated in field trials to assess the efficacy of the insect moulting hormone analog tebufenozide (Mimic®) against the eastern spruce budworm, Choristoneura fumiferana (Clem.). The pest biology, and habitat and pesticide characteristics were used as a basis to derive the required active ingredient (a.i.) and deposit density.

N. Payne; A. Retnakaran; B. Cadogan

1997-01-01

412

Average structural analysis of tar obtained from pyrolysis of wood.  

PubMed

Conventional analytical methods such as (1)H NMR, vapor pressure osmometry (VPO) and elemental analysis were used to characterize the tar obtained from pyrolysis of pine. The major fraction of tar obtained during pyrolysis of pine at different temperatures was the insoluble fraction in n-heptane which corresponds to asphaltenes; this fraction was characterized and analyzed using average structural parameters. The structural unit of the tar is composed of one aromatic ring substituted by aliphatic chains, olefinic groups and the presence of oxygenated groups. Two of such average structures determined with this methodology corresponds to 4-formyl-2,6-dimethoxy-3-[(1E)-prop-1-en-1-yl]-5-propylbenzoic acid and 2,3,5-trimethoxy-6-[(1E)-prop-1-en-1-yl]-4-propylbenzaldehyde. PMID:19962881

López, Diana; Acelas, Nancy; Mondragón, Fanor

2010-04-01

413

Transportation fuels from biomass via fast pyrolysis and hydroprocessing  

SciTech Connect

Biomass is a renewable source of carbon, which could provide a means to reduce the greenhouse gas impact from fossil fuels in the transportation sector. Biomass is the only renewable source of liquid fuels, which could displace petroleum-derived products. Fast pyrolysis is a method of direct thermochemical conversion (non-bioconversion) of biomass to a liquid product. Although the direct conversion product, called bio-oil, is liquid; it is not compatible with the fuel handling systems currently used for transportation. Upgrading the product via catalytic processing with hydrogen gas, hydroprocessing, is a means that has been demonstrated in the laboratory. By this processing the bio-oil can be deoxygenated to hydrocarbons, which can be useful replacements of the hydrocarbon distillates in petroleum. While the fast pyrolysis of biomass is presently commercial, the upgrading of the liquid product by hydroprocessing remains in development, although it is moving out of the laboratory into scaled-up process demonstration systems.

Elliott, Douglas C.

2013-09-21

414

The pyrolysis of toluene and ethyl benzene  

NASA Technical Reports Server (NTRS)

The pyrolysis of toluene at 850 to 950 C gave mainly H2, CH4, and benzene; PhEt at 650 to 750 C gave mainly H2, CH4, styrene, benzene, and toluene. The rate constants for PhEt pyrolysis were 1000 times higher than those for toluene pyrolysis; the chain initiation rate constants differed by the same factor. The activation energy differences were 46 kJ/mole for the total reaction and 54 kJ/mole for chain initiation. The chain length was evaluated for the PhEt case (10 + or - 2).

Sokolovskaya, V. G.; Samgin, V. F.; Kalinenko, R. A.; Nametkin, N. S.

1987-01-01

415

Quantitation of sugar content in pyrolysis liquids after acid hydrolysis using high-performance liquid chromatography without neutralization.  

PubMed

A rapid method for the quantitation of total sugars in pyrolysis liquids using high-performance liquid chromatography (HPLC) was developed. The method avoids the tedious and time-consuming sample preparation required by current analytical methods. It is possible to directly analyze hydrolyzed pyrolysis liquids, bypassing the neutralization step usually required in determination of total sugars. A comparison with traditional methods was used to determine the validity of the results. The calibration curve coefficient of determination on all standard compounds was >0.999 using a refractive index detector. The relative standard deviation for the new method was 1.13%. The spiked sugar recoveries on the pyrolysis liquid samples were between 104 and 105%. The research demonstrates that it is possible to obtain excellent accuracy and efficiency using HPLC to quantitate glucose after acid hydrolysis of polymeric and oligomeric sugars found in fast pyrolysis bio-oils without neutralization. PMID:25093902

Johnston, Patrick A; Brown, Robert C

2014-08-13

416

Spray applicator for spraying coatings and other fluids in space  

NASA Technical Reports Server (NTRS)

A self contained spray application is developed for one handed operation in a zero gravity vacuum environment by a free flying astronaut not attached to any spacecraft. This spray applicator eliminates contamination of the operator by back spray. This applicator includes a rigid accumulator containment of a fluid within a flexible bladder the fluid being urged out of the accumulator under pressure through a spray gun. The spray gun includes a spring loaded lockable trigger which controls a valve. When in an open position, the fluid passes through the valve into the ambient environment in the form of a spray. A spray shield is provided which directs the flow of the spray from the applicator by trapping errant particles of spray yet allowing the passage of escaping gases through its material.

Kuminecz, J. F.; Lausten, M. F. (inventors)

1985-01-01

417

Metal atomization spray nozzle  

DOEpatents

A spray nozzle for a magnetohydrodynamic atomization apparatus has a feed passage for molten metal and a pair of spray electrodes mounted in the feed passage. The electrodes, diverging surfaces which define a nozzle throat and diverge at an acute angle from the throat. Current passes through molten metal when fed through the throat which creates the Lorentz force necessary to provide atomization of the molten metal. 6 figures.

Huxford, T.J.

1993-11-16

418

Evaporating Spray in Supersonic Streams Including Turbulence Effects  

NASA Technical Reports Server (NTRS)

Evaporating spray plays an important role in spray combustion processes. This paper describes the development of a new finite-conductivity evaporation model, based on the two-temperature film theory, for two-phase numerical simulation using Eulerian-Lagrangian method. The model is a natural extension of the T-blob/T-TAB atomization/spray model which supplies the turbulence characteristics for estimating effective thermal diffusivity within the droplet phase. Both one-way and two-way coupled calculations were performed to investigate the performance of this model. Validation results indicate the superiority of the finite-conductivity model in low speed parallel flow evaporating sprays. High speed cross flow spray results indicate the effectiveness of the T-blob/T-TAB model and point to the needed improvements in high speed evaporating spray modeling.

Balasubramanyam, M. S.; Chen, C. P.

2006-01-01

419

Optimization of Fibrin Glue Spray Systems for Ophthalmic Surgery  

PubMed Central

Purpose To optimize fibrin glue (FG) spray for ophthalmic surgery using two spray applicators, EasySpray and DuploSpray systems, by varying the distance from point of application and the pressure/flow rate, and to compare the adhesive strength of sutured and sutureless (FG sprayed) conjunctival graft surgery in a rabbit model. Methods FG was sprayed on a 0.2 mm-thick sheet of paper using EasySpray by variously combining application distances of 2.5, 5, 7.5, and 10 cm with pressures of 10, 15, and 20 psi. DuploSpray was used at the same distances but with varying flow rates of 1 and 2 L/min. Subsequently, FG was sprayed on porcine corneas and FG thickness was analyzed by histology. In addition, adhesive strength of the conjunctival graft (0.5 × 0.5 cm) attached to the rabbit cornea by sutured and sutureless surgery (FG spray) was compared using a tension meter. Results Histology measurements revealed that the FG thickness decreased with increases in distance and pressure of spray using the EasySpray applicator on paper and porcine corneal sections. The adhesive strength of the sutured conjunctival graft (41 ± 4.85 [kilopascal] KPa) was found to be higher than the graft attached by spraying (10 ± 2.3 KPa) and the sequential addition of FG (6 ± 0.714 KPa). Conclusions The EasySpray applicator formed a uniform spread of FG at a distance-pressure combination of 5 cm and 20 psi. The conjunctival graft attached with sutures had higher adhesive strength compared with grafts glued with a spray applicator. Although the adhesive strength of FG applied through the applicator was similar to the drop-wise sequential technique, the former was more cost effective because more samples could be sprayed compared with the sequential manual technique. Translational Relevance The standardization of the spray system for the application of FG in ophthalmology will provide an economical method for delivering consistent healing results after surgery. PMID:24049702

Chaurasia, Shyam S.; Champakalakshmi, Ravi; Angunawela, Romesh I.; Tan, Donald T.; Mehta, Jodhbir S.

2012-01-01

420

Pyrolysis of solid waste in a rotary kiln: influence of final pyrolysis temperature on the pyrolysis products  

Microsoft Academic Search

Temperature is one of the most important parameters in pyrolysis reaction. In present work, an externally heated laboratory-scale rotary-kiln pyrolyser was designed and developed. The influence of final pyrolysis temperature (FPT) on the pyrolytic products of solid wastes has been studied. Raising FPT caused increasing gas yield and decreasing semi-coke yield. The average heat value of the gas also changed

A. M Li; X. D Li; S. Q Li; Y Ren; Y Chi; J. H Yan; K. F Cen

1999-01-01

421

Reaction mechanisms for toluene pyrolysis  

SciTech Connect

The rich chemistry occurring during the pyrolysis of toluene has been investigated by studying its decomposition in a single-pulse shock tube coupled with detailed chemical kinetic modeling to describe product formation. This work provides information on the initial decomposition steps of toluene and its primary radical benzyl as well as the detailed steps leading to the formation of polyaromatic hydrocarbons. Temperatures ranged from approximately 1,200 to 1,850 K for 1% toluene in argon, total pressures of approximately 10 atm, and residence times near 600 {micro}s. Pyrolysis products were collected and analyzed using gas chromatography. Profiles of hydrogen and hydrocarbons ranging from methane to pyrene were obtained. These semiquantitative data have been interpreted to help resolve many of the existing uncertainties involving the pyrolytic process. In particular, this work supports arguments for a low activation energy process for benzyl radical decomposition as evidenced by the low-temperature formation of cyclopentadiene and the radical recombination product, benzyl-cyclopentadienyl (b-cpd). Also, the data support suggestions for an important role of the methylphenyl radical, specifically in the formation of isomers of dimethyldiphenyl and as a key intermediate in the production of anthracene. Minimal evidence for rapid toluene decomposition to phenyl and methyl was found. Importantly, the data support general mechanisms proposed for ring growth sequences, although an additional important step involving ring closure and direct H{sub 2} elimination is suggested by the data. In addition, the data indicate rapid anthracene/phenanthrene isomerization above 1,600 K.

Colket, M.B.; Seery, D.J. [United Technologies Research Center, East Hartford, CT (United States)

1994-12-31

422

Studies on the structural, electrical and optical properties of Al-doped ZnO thin films prepared by chemical spray deposition  

Microsoft Academic Search

Aluminium-doped zinc oxide films have been prepared by chemical spray pyrolysis technique. Variation of structural, morphological, electrical and optical properties with doping concentration is investigated in detail. The films were highly transparent to visible radiation and electrically conductive. XRD studies have shown that the films were polycrystalline in nature with (002) preferred orientation. SEM studies have revealed the smooth polycrystalline

Benny Joseph; P. K. Manoj; V. K. Vaidyan

2006-01-01

423

Size-velocity correlations in hybrid high order moment/multi-fluid methods for polydisperse evaporating sprays: Modeling and numerical issues  

NASA Astrophysics Data System (ADS)

Kah et al. (2010) [30,33] recently developed the Eulerian multi-size moment model (EMSM) which tackles the modeling and numerical simulation of polydisperse multiphase flows. Using a high order moment method in a compact interval, they suggested to reconstruct the number density function (NDF) by entropy maximization, which leads to a unique and realizable NDF, potentially in several size intervals, thus leading to an hybrid method between Multifluid and high order. This reconstruction is used to simulate the evaporation process, by an evaluation of the flux of droplet disappearance at zero size, the fluxes of droplets between size intervals, and an accurate description of the size shift induced by evaporation Massot et al. (2010) [15]. Although this method demonstrated its potential for evaporating polydisperse flows, two issues remain to be addressed. First, the EMSM only considers one velocity for all droplets, thus decoupling size from velocity, which is too restrictive for distributions with a large size spectrum. In most applications size-conditioned dynamics have to be accounted for. Second, the possibility to have separated dynamics for each size can lead to quasi-monodisperse distributions, which corresponds to a hard limiting case for the EM algorithm. So the behavior of the algorithm needs to be investigated, in order to reproduce the entire moment space with a reasonable accuracy. The aim of this paper is thus twofold. The EM and its related algorithm are enhanced by using a more accurate integration method in order to handle NDF close to the frontier of the moment space associated with an adaptive number of parameters to reconstruct the NDF accurately and efficiently, as well as tabulated initial guess to optimize the computational time. Then, a new model called CSVM (coupled size-velocity moments model) is introduced. Size-velocity correlations are addressed either in the evaporation and drag processes, or in the convective transport. To reach this goal, a velocity reconstruction for each size is suggested, using only one additional moment per dimension, and which can be directly applied to several size intervals. Thus, this method is a direct generalization of EMSM. To handle the convective transport, a flux splitting scheme is proposed, based on the underlying kinetic description of the disperse phase. Comparing to existing approaches, a main novelty of the CSVM is that our kinetic approach ensures built-in realizability conditions, no additional corrections of the moments being needed at each time step. The full strategy is first evaluated in 0D and 1D cases, which either demonstrates the ability to reproduce both evaporation, drag force and convection with size-velocity correlations, or the possible extension to several size intervals. Finally, the method is applied on 2D cases with only one section, showing the ability of the CSVM and its related algorithms to capture the main physics of polydisperse evaporating sprays with a minimal number of moments.

Vié, Aymeric; Laurent, Frédérique; Massot, Marc

2013-03-01

424

Pyrolysis of D-Glucose to Acrolein  

NASA Astrophysics Data System (ADS)

Despite of its great importance, the detailed molecular mechanism for carbohydrate pyrolysis remains poorly understood. We perform a density functional study with a newly developed XYG3 functional on the processes for D-glucose pyrolysis to acrolein. The most feasible reaction pathway starts from an isomerization from D-glucose to D-fructose, which then undergoes a cyclic Grob fragmentation, followed by a concerted electrocyclic dehydration to yield acrolein. This mechanism can account for the known experimental results.

Shen, Chong; Zhang, Igor Ying; Fu, Gang; Xu, Xin

2011-06-01

425

Behavior of sulfur during coal pyrolysis  

USGS Publications Warehouse

The behavior of sulfur in Illinois coals during pyrolysis was evaluated by thermogravimetry/ Fourier transform-infrared spectroscopy (TG/FT-IR) techniques. SO2, COS, and H2S were major gaseous sulfur-containing products observed during coal pyrolysis. The release rates of the gaseous sulfur species showed several peaks within the temperature ranges, which were due to the emission of different forms of sulfur in coal. ?? 1994.

Shao, D.; Hutchinson, E.J.; Heidbrink, J.; Pan, W.-P.; Chou, C.-L.

1994-01-01

426

Pyrolysis of Waste Tires with Copper Nitrate  

Microsoft Academic Search

Influence of copper(?)nitrate(CN) on the pyrolysis of waste tires in 50 cm static batch reactor in a nitrogen atmosphere are studied. The products of pyrolysis was investigated with in situ Fourier transform infrared (FT-IR) spectroscopy as well as off-line gas chromatography\\/Mass spectrometry (GC-MS). The combination of FT-IR and GC\\/MS analysis was able to elucidate the effects of CN. Comparing with

QING-CAO KE-CHANG XIE; WEI-REN BAO; WEI-HUANG; JIAN-BING ZHAO

2004-01-01

427

Production of bran castor biochar through slow pyrolysis  

NASA Astrophysics Data System (ADS)

Pyrolysis is a thermal process of great importance in the present context, since it constitutes a significant alternative to adequate use of organic waste. The principal products obtained in the pyrolysis of discarded biomass are bio-oil, biogas and biochar. Biochar, in turn, may play a relevant role when applied to the soil to sequester carbon and as a soil conditioner, a material comparable to organic matter of Indians Black Earths from the Amazon Region [1]. Seeking to determine the best methods of preparation of biochar, we studied the pyrolysis of bran castor residue of the Brazilian biodiesel industry. Eight samples, from FM1 to FM8, were prepared in a factorial design 23 using two temperature (300 and 350 °C), two heating velocity (5 and 10 °C min-1) and two period of heating (30 and 60 min). The eight samples were studied using the spectroscopy: EPR, FTIR, RMN, XPS, and elemental analysis. By elemental analysis, the samples that keep for lower temperature of pyrolysis, 300 °C, showed H/C and N/C ratios greater than the samples of 350 °C. That higher value can be attributed to chemical structure more aliphatic than aromatic mainly in the FM7 sample (V = 10 °C min-1, T = 300 °C, P = 30 min). The greater N/C ratio correlated with a superior amount of nitrogenous functions, presenting by both FM7 and FM4 samples, as determined by 13C NMR spectroscopy with absorptions in 175 ppm (amide) and 55 ppm (N-alkyl).

Pissinati de Rezende, E. I.; Mangrich, A. S.; Batista, M. G. F.; Toledo, J. M. S.; Novotny, E. H.

2012-04-01

428

Mechanism of fast pyrolysis of lignin: studying model compounds.  

PubMed

Fast pyrolysis of lignin is one of the most promising methods to convert the complex and irregular structure of lignin into renewable chemicals and fuel. During pyrolysis the complex set of radical reactions, rearrangements, and eliminations is influenced by temperature, pressure, and the lignin origin and structure. This model compound study aims to understand reaction pathways and how primary intermediates lead to the observed product selectivity. The pyrolysis microreactor directly connected to the gas chromatograph with a mass spectrometer (py-GC/MS) detects the final products, while imaging photoelectron photoion coincidence (iPEPICO) with VUV synchrotron radiation shows primary decomposition radicals. The tested model compounds, diphenylether (DPE) and ortho-methoxyphenol (guaiacol), represent a common lignin linkage and the most present subunit in lignin, respectively. Radical fragments, such as the hydroxycyclopentadienyl radical in guaiacol decomposition, are identified by mass-selected threshold photoelectron spectra (ms-TPES) in excellent agreement with the Franck-Condon simulation. While homolysis produces phenoxy-, phenyl-, and hydroxyphenoxy radicals, which are observed in high vacuum, radically initiated reactions are dominant in ambient conditions and produce recombination and rearrangement products, such as 2-hydroxybenzaldehyde in the case of guaiacol. The degree of substitution plays a dominant role in both the stabilization of the intermediate radical and the following degree of recombination. The recombination of phenoxy radicals is enhanced compared to hydroxy-phenoxy radicals. PMID:24937704

Custodis, Victoria B F; Hemberger, Patrick; Ma, Zhiqiang; van Bokhoven, Jeroen A

2014-07-24

429

CORROSIVITY AND COMPOSITION OF RAW AND TREATED PYROLYSIS OILS  

SciTech Connect

Fast pyrolysis offers a relatively low cost method of processing biomass to produce a liquid product that has the potential for conversion to several types of liquid fuels. The liquid product of fast pyrolysis, known as pyrolysis oil or bio-oil, contains a high oxygen content primarily in the form of water, carboxylic acids, phenols, ketones and aldehydes. These oils are typically very acidic with a Total Acid Number that is often in the range of 50 to 100, and previous studies have shown this material to be quite corrosive to common structural materials. Removal of at least some of the oxygen and conversion of this oil to a more useful product that is considerably less corrosive can be accomplished through a hydrogenation process. The product of such a treatment is considered to have the potential for blending with crude oil for processing in petroleum refineries. Corrosion studies and chemical analyses have been conducted using as produced bio-oil samples as well as samples that have been subjected to different levels of oxygen removal. Chemical analyses show treatment affected the concentrations of carboxylic acids contained in the oil, and corrosion studies showed a positive benefit of the oxygen removal. Results of these studies will be presented in this paper.

Keiser, Jim; Howell, Michael; Connatser, Raynella M.; Lewis, Sam; Elliott, Douglas C.

2012-10-14

430

Measurements in liquid fuel sprays  

NASA Astrophysics Data System (ADS)

Techniques for studying the events directly preceding combustion in the liquid fuel sprays are being used to provide information as a function of space and time on droplet size, shape, number density, position, angle of flight and velocity. Spray chambers were designed and constructed for: (1) air-assist liquid fuel research sprays; (2) high pressure and temperature chamber for pulsed diesel fuel sprays; and (3) coal-water slurry sprays. Recent results utilizing photography, cinematography, and calibration of the Malvern particle sizer are reported. Systems for simultaneous measurement of velocity and particle size distributions using laser Doppler anemometry interferometry and the application of holography in liquid fuel sprays are being calibrated.

Chigier, N.

1984-04-01

431

Role of Lamellae Morphology on the Microstructural Development and Mechanical Properties of Small-Particle Plasma-Sprayed Alumina  

Microsoft Academic Search

The influence of spray parameters on the microstructure and flexural strength of plasma-sprayed alumina was investigated. Coatings were applied using a small-particle plasma spray (SPPS) method, which is a recently patented process that allows submicrometer-sized powders to be sprayed. Using identical starting powders, coatings that were produced using two distinctly different spray conditions exhibited significant differences in both microstructure and

Rodney W. Trice; K. T. Faber

2004-01-01

432

40 CFR 61.146 - Standard for spraying.  

...POLLUTANTS National Emission Standard for Asbestos § 61.146 Standard for spraying...owner or operator of an operation in which asbestos-containing materials are spray applied...material containing more than 1 percent asbestos as determined using the method...

2014-07-01

433

Optimal feature extraction for segmentation of Diesel spray images.  

PubMed

A one-dimensional simplification, based on optimal feature extraction, of the algorithm based on the likelihood-ratio test method (LRT) for segmentation in colored Diesel spray images is presented. If the pixel values of the Diesel spray and the combustion images are represented in RGB space, in most cases they are distributed in an area with a given so-called privileged direction. It is demonstrated that this direction permits optimal feature extraction for one-dimensional segmentation in the Diesel spray images, and some of its advantages compared with more-conventional one-dimensional simplification methods, including considerably reduced computational cost while accuracy is maintained within more than reasonable limits, are presented. The method has been successfully applied to images of Diesel sprays injected at room temperature as well as to images of sprays with evaporation and combustion. It has proved to be valid for several cameras and experimental arrangements. PMID:15074419

Payri, Francisco; Pastor, José V; Palomares, Alberto; Juliá, J Enrique

2004-04-01

434

Characterisations Of Al{sub 2}O{sub 3}-13% Wt TiO{sub 2} Deposition On Mild Steel Via Plasma Spray Method  

SciTech Connect

To date, plasma sprayed alumina titania have been widely used as wear resistance coatings in textile, machinery and printing industries. Previous studies showed that the coating microstructures and properties were strongly depended on various parameters such as ceramic composition, grain size powders and spray parameters, thus, influencing the melting degree of the alumina titania during the deposition process. The aim of this study focuses on the evolution of the micron sizes of alumina-13%wt titania at different plasma spray power, ranging from 20kW to 40kW. It was noted that the coating porosity of alumina-13%wt titania were decreased from 6.2% to 4% by increasing the plasma power from 20 to 40 kW. At lower power value, partially melted powders were deposited, generating over 6% porosity within the microstructures. Percentage of porosity about 5.6% gave the best ratio of bi-modal structures, providing the highest microhardness value. Furthermore, the effect of microstructure and porosity formation on wear resistance was also discussed. Coatings with less porosity exhibited better resistance to wear, in which the wear resistance of coated mild steel possessed only {approx}5 x 10{sup -4} cm{sup 3}/Nm with 4% of porosity.

Yusoff, N. H.; Isa, M. C. [Maritime Technology Divison, Science And Technology Research Institute For Defence (STRIDE) c/o KD MALAYA 32100 Pangkalan TLDM, Lumut, Perak (Malaysia); Ghazali, M. J.; Muchtar, A.; Forghani, S. [Dept. of Mechanical and Materials Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM, Bangi, Selangor (Malaysia); Daud, A. R. [School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM, Bangi, Selangor (Malaysia)

2011-01-17

435

Decaking of coal or oil shale during pyrolysis in the presence of iron oxides  

DOEpatents

A method for producing a fuel from the pyrolysis of coal or oil shale in the presence of iron oxide in an inert gas atmosphere. The method includes the steps of pulverizing feed coal or oil shale, pulverizing iron oxide, mixing the pulverized feed and iron oxide, and heating the mixture in a gas atmosphere which is substantially inert to the mixture so as to form a product fuel, which may be gaseous, liquid and/or solid. The method of the invention reduces the swelling of coals, such as bituminous coal and the like, which are otherwise known to swell during pyrolysis.

Khan, M. Rashid (Morgantown, WV)

1989-01-01

436

Decaking of coal or oil shale during pyrolysis in the presence of iron oxides  

DOEpatents

A method for producing a fuel from the pyrolysis of coal or oil shale in the presence of iron oxide in an inert gas atmosphere is described. The method includes the steps of pulverizing feed coal or oil shale, pulverizing iron oxide, mixing the pulverized feed and iron oxide, and heating the mixture in a gas atmosphere which is substantially inert to the mixture so as to form a product fuel, which may be gaseous, liquid and/or solid. The method of the invention reduces the swelling of coals, such as bituminous coal and the like, which are otherwise known to swell during pyrolysis. 4 figs., 8 tabs.

Rashid Khan, M.

1988-05-05

437

Analysis of photographic records of coal pyrolysis  

SciTech Connect

Bituminous coals upon heating undergo melting and pyrolytic decomposition with significant parts of the coal forming an unstable liquid that can escape from the coal by evaporation. The transient liquid within the pyrolyzing coal causes softening or plastic behavior that can influence the chemistry and physics of the process. Bubbles of volatiles can swell the softened coal mass in turn affecting the combustion behavior of the coal particles. The swelling behavior of individual coal particles has to be taken into account both as the layout as well as for the operation of pyrolysis, coking and performance of coal-fired boilers. Increased heating rates generally increase the amount of swelling although it is also known that in some cases, even highly swelling coals can be transformed into char with no swelling if they are heated slowly enough. The swelling characteristics of individual coal particles have been investigated by a number of workers employing various heating systems ranging from drop tube and shock tube furnaces, flow rate reactors and electrical heating coils. Different methods have also been employed to determine the swelling factors. The following sections summarize some of the published literature on the subject and outline the direction in which the method of analysis will be further extended in the study of the swelling characteristics of hvA bituminous coal particles that have been pyrolyzed with a laser beam.

Dodoo, J.N.D.

1991-10-01

438

Peat pyrolysis and the analytical semi-empirical model  

SciTech Connect

Pyrolysis of peat could convert this material into useful fuels and valuable hydrocarbons. A study of peat pyrolysis can also serve as a useful bridge between studies of coal pyrolysis and biomass pyrolysis. Using an analytical model of pyrolysis that has previously been applied to biomass and to coal, we present here the results of applications of this model to a representative peat. The analysis suggests means of organizing and processing rate and yield data that should be useful in applications of pyrolysis for the production of fuels and chemicals.

Feng, J.; Green, A.E.S. [University of Florida, Gainesville, FL (United States). Clean Combustion Technology Laboratory

2007-07-01

439

A pyrolysis study for the thermal and kinetic characteristics of an agricultural waste with two different plastic wastes.  

PubMed

In this study, thermochemical conversion of plastic wastes (PET and PVC) together with an agricultural waste (hazelnut shell) was investigated. In order to determine the thermal and kinetic behaviours, pyrolysis experiments were carried out from room temperature to 800 °C, with a heating rate of 10 °C min(-1) in the presence of a N2 atmosphere in a thermogravimetric analyzer. With the obtained thermogravimetric data, an appropriate temperature was specified for the pyrolysis of biomass-plastic wastes in a fixed-bed reactor. At the second step, pyrolysis experiments were carried out at the same conditions with the thermogravimetric analyzer, except the final temperature which was up to 500 °C in this case. After pyrolysis experiments, pyrolysis yields were calculated and characterization studies for bio-oil were investigated. Experimental results showed that co-pyrolysis has an important role in the determination of the pyrolysis mechanism and the process conditions while designing/implementing a thermochemical conversion method where biomass-plastic materials were preferred as raw materials. PMID:25062939

Cepelio?ullar, Ozge; Pütün, Ay?e E

2014-10-01

440

An automated on-line method for simultaneous analysis of phenothiazines in human serum by high-performance liquid chromatography\\/sonic spray ionization mass spectrometry using backflush column switching  

Microsoft Academic Search

An automated on-line method for simultaneous analysis of five phenothiazine drugs by high-performance liquid chromatography\\u000a (HPLC)\\/sonic spray ionization mass spectrometry (SSI-MS) has been established, using backflush column switching. A 400-?l\\u000a portion of serum sample diluted 81-fold with distilled water was subjected to the on-line system. In the system, an Oasis\\u000a HLB cartridge was used as the precolumn for extraction; large

Ruri Aoki; Tetsuya Arinobu; Takeshi Kumazawa; Hideki Hattori; Hiroshi Noguchi

2007-01-01

441

Acoustic effects of sprays  

NASA Technical Reports Server (NTRS)

Since the early 1960's, it has been known that realistic combustion models for liquid fuel rocket engines should contain at least a rudimentary treatment of atomization and spray physics. This is of particular importance in transient operations. It has long been recognized that spray characteristics and droplet vaporization physics play a fundamental role in determining the stability behavior of liquid fuel rocket motors. This paper gives an overview of work in progress on design of a numerical algorithm for practical studies of combustion instabilities in liquid rocket motors. For flexibility, the algorithm is composed of semi-independent solution modules, accounting for different physical processes. Current findings are report and future work is indicated. The main emphasis of this research is the development of an efficient treatment to interactions between acoustic fields and liquid fuel/oxidizer sprays.

Pindera, Maciej Z.; Przekwas, Andrzej J.

1994-01-01

442

Spray forming technology  

SciTech Connect

The main attraction of spray forming is the single step required to change a molten alloy into a consolidated product. Semi-finished product shapes fabricated by spraying gas-atomized molten metal droplets onto a substrate are free from micro-segregation, are low in oxygen content, and exhibit enhanced hot workability. Other process benefits include low capital costs (less equipment required); low operating costs (low energy consumption and high material yields); and low overhead costs (less stock and work-in-progress, with shorter delivery). In spite of these benefits, significant advances in the spray forming process are necessary in order to compete in the commercial marketplace against high-volume, established ingot metallurgy processes involving ingot casting, forging, and/or rolling. Toward this end, much progress has recently been made.

Leatham, A. [Osprey Metals Ltd., Neath (United Kingdom)

1996-08-01

443

Study of plasma- and detonation gun-sprayed alumina coatings using taguchi experimental design  

Microsoft Academic Search

Atmospheric plasma spraying (APS) is a most versatile thermal spray method for depositing alumina (Al2O3) coatings, and detonation gun (D-gun) spraying is an alternative thermal spray technology for depositing such coatings with\\u000a extremely good wear characteristics. The present study is aimed at comparing the characteristics of Al2O3 coatings deposited using the above techniques by using Taguchi experimental design.\\u000a \\u000a Alumina coating

P. Saravanan; V. Selvarajan; M. P. Srivastava; D. S. Rao; S. V. Joshi; G. Sundararajan

2000-01-01

444

MALDI-TOF study of oligomers distribution in spray-dried glyoxalated lignin for wood adhesives  

Microsoft Academic Search

Spray drying of glyoxalated lignin used in tannin\\/lignin adhesives for exterior- and interior-grade wood particleboard and other types of panels has been shown to be capable of maintaining its reactivity after spray drying with no decrease in performance of the adhesive once the spray-dried material is re-dissolved in water. This indicates that spray drying is a very suitable method for

P. Navarrete; A. Pizzi; K. Rode; M. Vignali; H. Pasch

2012-01-01

445

Optimization of Atmospheric Plasma Spray Process Parameters using a Design of Experiment for Alloy 625 coatings  

Microsoft Academic Search

Alloy 625 is a Ni-based superalloy which is often a good solution to surface engineering problems involving high temperature\\u000a corrosion, wear, and thermal degradation. Coatings of alloy 625 can be efficiently deposited by thermal spray methods such\\u000a as Air Plasma Spraying. As in all thermal spray processes, the final properties of the coatings are determined by the spraying\\u000a parameters. In

F. Azarmi; T. W. Coyle; J. Mostaghimi

2008-01-01

446

Catalytic fast pyrolysis of lignocellulosic biomass.  

PubMed

Increasing energy demand, especially in the transportation sector, and soaring CO2 emissions necessitate the exploitation of renewable sources of energy. Despite the large variety of new energy carriers, liquid hydrocarbon still appears to be the most attractive and feasible form of transportation fuel taking into account the energy density, stability and existing infrastructure. Biomass is an abundant, renewable source of energy; however, utilizing it in a cost-effective way is still a substantial challenge. Lignocellulose is composed of three major biopolymers, namely cellulose, hemicellulose and lignin. Fast pyrolysis of biomass is recognized as an efficient and feasible process to selectively convert lignocellulose into a liquid fuel-bio-oil. However bio-oil from fast pyrolysis contains a large amount of oxygen, distributed in hundreds of oxygenates. These oxygenates are the cause of many negative properties, such as low heating value, high corrosiveness, high viscosity, and instability; they also greatly limit the application of bio-oil particularly as transportation fuel. Hydrocarbons derived from biomass are most attractive because of their high energy density and compatibility with the existing infrastructure. Thus, converting lignocellulose into transportation fuels via catalytic fast pyrolysis has attracted much attention. Many studies related to catalytic fast pyrolysis of biomass have been published. The main challenge of this process is the development of active and stable catalysts that can deal with a large variety of decomposition intermediates from lignocellulose. This review starts with the current understanding of the chemistry in fast pyrolysis of lignocellulose and focuses on the development of catalysts in catalytic fast pyrolysis. Recent progress in the experimental studies on catalytic fast pyrolysis of biomass is also summarized with the emphasis on bio-oil yields and quality. PMID:24801125

Liu, Changjun; Wang, Huamin; Karim, Ayman M; Sun, Junming; Wang, Yong

2014-10-20

447

Natural gas pyrolysis in the regenerative gas heater Part ii: Natural gas pyrolysis in the free volume of the regenerative gas heater  

Microsoft Academic Search

This paper discusses the results of an experimental study of a new method of natural gas pyrolysis based on thermal decomposition in a flow of high temperature carrier gas preliminary heated in the regenerative heater matrix. It has been shown that in this case the methane carbon is almost completely converted into black carbon and no pyrocarbon is produced in

R. G Popov; E. E Shpilrain; V. M Zaytchenko

1999-01-01

448

The pyrolysis of oil sands in a fluidized bed at reduced pressure  

SciTech Connect

A fluidized bed pyrolysis reactor system was designed, constructed, and tested at reactor pressures less than atmospheric using mined and crushed oil sands from the Whiterocks deposit of Utah. A 6.0 inch ID fluidized bed reactor was fed oil sand of 7% bitumen saturation on a continuous basis while maintaining a bed height of approximately 12 inches. Spent sand was withdrawn using a modified nonmechanical L valve. The characteristics of bed pressure drop, [Delta]P[sub B], versus superficial gas velocity, U, were determined during fluidization and defluidization of spent sand using laboratory air. A proposed method for interpreting the minimum fluidization gas velocity, U[sub mf], from [Delta]P[sub B] versus U curves for multisized particles at reduced pressure was tested. U[sub mf] values were consistent with predictive correlations in the literature. The relationship, U[sub mf] T[sup 0.27] = a constant, was tested and found to be valid from 295 K to 559 K for spent sand fluidized by air. The reactor used propane for heating and the hot propane combustion product gases for fluidization during pyrolysis. Liquid products were condensed and filtered using commercial basket strainers modified with water cooling coils. Material balances of 90% or more were obtained for pyrolysis experiments at 450[degrees]C, 475[degrees]C, and 500[degrees]C. The optimum pyrolysis temperature for liquid yields was found to be 475[degrees]C at average retention times of thirty minutes or more. For pyrolysis temperatures of 475[degrees]C or lower, recovered oil sand pyrolysis products were 88 wt% liquid, 9 wt% coke, and 3 wt% gas. Liquid yields from the fluidized bed pyrolysis of Whiterocks oil sands at reduced pressure were greater than reported yields from a rotary kiln or an atmospheric pressure fluidized bed. Coke on the spent sand was about 0.6 wt% of the spent sand and represented about 8 wt% of the bitumen pyrolyzed.

Fletcher, J.V.

1992-01-01

449

Spray deposition - A summary  

NASA Astrophysics Data System (ADS)

Important findings are presented from six studies concerning the application of the Osprey metal spray-deposition process to (1) Cu-base alloys, (2) Cu-base case-hardening alloys, (3) preform formation, (4) 7075 and 8090 Al alloys, (5) superalloys, and (6) superalloy tubes. It is in the aggregate shown that while the details of the process are materials-specific, there are no technical barriers to scale-up and commercialization. Each of the alloy systems considered can be spray-formed into various near-net-shape products.

Lewis, Richard E.; Lawley, Alan

450

Thermal behaviour and kinetics of alga Polysiphonia elongata biomass during pyrolysis.  

PubMed

The pyrolysis characteristics and kinetics of Polysiphonia elongata were investigated using a thermogravimetric analyzer. The main decomposition of samples occurred between 225°C and 485°C at heating rates of 5-40°C/min; owing to release of 78-82% of total volatiles. The heating rate effected pyrolysis characteristics such as maximum devolatilization rate and decomposition temperature. However, total volatile matter yield was not significantly affected by heating rate. The activation energy of pyrolysis reaction was calculated by model free Friedman and Kissenger-Akahira-Sunose methods and mean values were 116.23kJ/mol and 126.48kJ/mol, respectively. A variance in the activation energy with the proceeding conversions was observed for the models applied, which shows that the pyrolysis process was composed of multi-step kinetics. The Coats-Redfern method was used to determine pre-exponential factor and reaction order. The obtained parameters were used in simulation of pyrolysis process and results were in a good agreement with experimental data. PMID:25194914

Ceylan, Selim; Topcu, Y?ld?ray; Ceylan, Zeynep

2014-11-01

451

Fullerene synthesis by laser pyrolysis of hydrocarbons  

NASA Astrophysics Data System (ADS)

A novel route for the synthesis of carbon soots containing fullerenes has been developed i.e. the pyrolysis of hydrocarbons in gas, vapour or aerosol phase, which are heated and decomposed through the absorption of IR photons emitted by a high power CW CO2 laser. Hydrocarbons such as benzene (+ cyclopentadiene), acetylene or ethylene have been tested, pure or mixed with an oxidizer agent (nitrous oxide or oxygen) and/or a sensitizer (sulfur hexafluoride). The fullerenes were identified in the soots obtained by using as precursor the benzene/oxygen or acetylene/oxygen mixture. When these compounds are produced in significant amounts they can be detected directly in the as-formed soots by Fourier Transform Infrared Spectroscopy (FTIR). For small quantities, a Soxhlet extraction procedure is necessary and the extracts are characterized by FTIR and by other methods which are more sensitive, like mass spectrometry or High Performance Liquid Chromatography (HPLC) coupled with ultraviolet-visible spectroscopy. The influence of the operating conditions is discussed.

Armand, X.; Herlin, N.; Voicu, I.; Cauchetier, M.

1997-11-01

452

Well-to-wheels analysis of fast pyrolysis pathways with the GREET model.  

SciTech Connect

The pyrolysis of biomass can help produce liquid transportation fuels with properties similar to those of petroleum gasoline and diesel fuel. Argonne National Laboratory conducted a life-cycle (i.e., well-to-wheels [WTW]) analysis of various pyrolysis pathways by expanding and employing the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model. The WTW energy use and greenhouse gas (GHG) emissions from the pyrolysis pathways were compared with those from the baseline petroleum gasoline and diesel pathways. Various pyrolysis pathway scenarios with a wide variety of possible hydrogen sources, liquid fuel yields, and co-product application and treatment methods were considered. At one extreme, when hydrogen is produced from natural gas and when bio-char is used for process energy needs, the pyrolysis-based liquid fuel yield is high (32% of the dry mass of biomass input). The reductions in WTW fossil energy use and GHG emissions relative to those that occur when baseline petroleum fuels are used, however, is modest, at 50% and 51%, respectively, on a per unit of fuel energy basis. At the other extreme, when hydrogen is produced internally via reforming of pyrolysis oil and when bio-char is sequestered in soil applications, the pyrolysis-based liquid fuel yield is low (15% of the dry mass of biomass input), but the reductions in WTW fossil energy use and GHG emissions are large, at 79% and 96%, respectively, relative to those that occur when baseline petroleum fuels are used. The petroleum energy use in all scenarios was restricted to biomass collection and transportation activities, which resulted in a reduction in WTW petroleum energy use of 92-95% relative to that found when baseline petroleum fuels are used. Internal hydrogen production (i.e., via reforming of pyrolysis oil) significantly reduces fossil fuel use and GHG emissions because the hydrogen from fuel gas or pyrolysis oil (renewable sources) displaces that from fossil fuel natural gas and the amount of fossil natural gas used for hydrogen production is reduced; however, internal hydrogen production also reduces the potential petroleum energy savings (per unit of biomass input basis) because the fuel yield declines dramatically. Typically, a process that has a greater liquid fuel yield results in larger petroleum savings per unit of biomass input but a smaller reduction in life-cycle GHG emissions. Sequestration of the large amount of bio-char co-product (e.g., in soil applications) provides a significant carbon dioxide credit, while electricity generation from bio-char combustion provides a large energy credit. The WTW energy and GHG emissions benefits observed when a pyrolysis oil refinery was integrated with a pyrolysis reactor were small when compared with those that occur when pyrolysis oil is distributed to a distant refinery, since the activities associated with transporting the oil between the pyrolysis reactors and refineries have a smaller energy and emissions footprint than do other activities in the pyrolysis pathway.

Han, J.; Elgowainy, A.; Palou-Rivera, I.; Dunn, J.B.; Wang, M.Q. (Energy Systems)

2011-12-01

453

Towards identification of traditional European and indigenous Australian paint binders using pyrolysis gas chromatography mass spectrometry.  

PubMed

We report a pyrolysis GC-MS method capable of analysing Indigenous Australian and European binders typically used in the manufacture of culturally important painted works. Eleven different traditional European binders and ten different Indigenous Australian binders were examined. The method allows discrimination between highly complex and impure lipid, resin, polysaccharide, wax, and protein-based binders. Each was found to have characteristic pyrolysis products that were unique to the binder material, demonstrating the potential for differentiation of these binders on Australian Aboriginal artworks towards identification and conservation of cultural heritage. PMID:24216215

Reeves, Tiffany; Popelka-Filcoff, Rachel S; Lenehan, Claire E

2013-11-25

454

Numerical simulation of the pyrolysis zone in a downdraft gasification process.  

PubMed

Models of the gasification process are mostly based on lumped analysis with distinct zones of the process treated as one entity. The study presented here was conducted to develop a more useful model specifically for the pyrolysis zone of the reactor of a downdraft gasifier based on finite computation method. Applying principles of energy and mass conservation, governing equations formed were solved by implicit finite difference method on the node of 100 throughout the length of the considered pyrolysis range (20 cm). Heat transfer considered convection, conduction, and the influence of solid radiation components. Chemical kinetics concept was also adopted to simultaneously solve the temperature profile and feedstock consumption rate on the pyrolysis zone. The convergence criteria were set at 10(-6) and simulation used Fortran Power Station 4.0. Validation experiments were also conducted resulting in maximum deviation of 24 degrees C and 0.37 kg/h for temperature and feedstock feed rate, respectively. PMID:19631526

Jaojaruek, K; Kumar, S

2009-12-01

455

Plasma-Spray Metal Coating On Foam  

NASA Technical Reports Server (NTRS)

Molds, forms, and other substrates made of foams coated with metals by plasma spraying. Foam might be ceramic, carbon, metallic, organic, or inorganic. After coat applied by plasma spraying, foam left intact or removed by acid leaching, conventional machining, water-jet cutting, or another suitable technique. Cores or vessels made of various foam materials plasma-coated with metals according to method useful as thermally insulating containers for foods, liquids, or gases, or as mandrels for making composite-material (matrix/fiber) parts, or making thermally insulating firewalls in automobiles.

Cranston, J.

1994-01-01

456

Pyrolysis Research: Bioenergy Testing and Analysis Laboratory BIOENERGY PROGRAM  

E-print Network

Pyrolysis Research: Bioenergy Testing and Analysis Laboratory BIOENERGY PROGRAM Pyrolysis research is conducted at Texas A&M University at the Bioenergy Testing and Analysis Laboratory. Our researchers create

457

Thermal spray manual for machinery components  

SciTech Connect

The Thermal Spray Manual For Machinery Components is a National Shipbuilding Research (SP-7) Project. This Manual is being developed by Puget Sound Naval Shipyard with the help of other government thermal spray facilities and SP-7 panel members. The purpose of the manual is to provide marine repair facilities with a ``how to do`` document that will be ``user friendly`` and known to be technically sound through production experience. The manual`s intent is to give marine repair facilities the ability to maximize the thermal spray process as a repair method for machinery components and to give these facilities guidelines on how to become qualified to receive certification that they meet the requirements of Military Standard 1687A.

Travis, R.; Ginther, C.; Herbstritt, M.; Herbstritt, J. [Puget Sound Naval Shipyard, Bremerton, WA (United States)

1995-12-31

458

Pyrolysis of waste tyres: a review.  

PubMed

Approximately 1.5 billion tyres are produced each year which will eventually enter the waste stream representing a major potential waste and environmental problem. However, there is growing interest in pyrolysis as a technology to treat tyres to produce valuable oil, char and gas products. The most common reactors used are fixed-bed (batch), screw kiln, rotary kiln, vacuum and fluidised-bed. The key influence on the product yield, and gas and oil composition, is the type of reactor used which in turn determines the temperature and heating rate. Tyre pyrolysis oil is chemically very complex containing aliphatic, aromatic, hetero-atom and polar fractions. The fuel characteristics of the tyre oil shows that it is similar to a gas oil or light fuel oil and has been successfully combusted in test furnaces and engines. The main gases produced from the pyrolysis of waste tyres are H(2), C(1)-C(4) hydrocarbons, CO(2), CO and H(2)S. Upgrading tyre pyrolysis products to high value products has concentrated on char upgrading to higher quality carbon black and to activated carbon. The use of catalysts to upgrade the oil to a aromatic-rich chemical feedstock or the production of hydrogen from waste tyres has also been reported. Examples of commercial and semi-commercial scale tyre pyrolysis systems show that small scale batch reactors and continuous rotary kiln reactors have been developed to commercial scale. PMID:23735607

Williams, Paul T

2013-08-01

459

Catalytic pyrolysis using UZM-39 aluminosilicate zeolite  

DOEpatents

A new family of coherently grown composites of TUN and IMF zeotypes has been synthesized and show to be effective catalysts for catalytic pyrolysis of biomass. These zeolites are represented by the empirical formula. Na.sub.nM.sub.m.sup.n+R.sub.rQ.sub.qAl.sub1-xE.sub.xSi.sub.yO.s- ub.z where M represents zinc or a metal or metals from Group 1, Group 2, Group 3 or the lanthanide series of the periodic table, R is an A,.OMEGA.-dihalosubstituted paraffin such as 1,4-dibromobutane, Q is a neutral amine containing 5 or fewer carbon atoms such as 1-methylpyrrolidine and E is a framework element such as gallium. The process involves contacting a carbonaceous biomass feedstock with UZM-39 at pyrolysis conditions to produce pyrolysis gases comprising hydrocarbons. The catalyst catalyzes a deoxygenation reaction converting oxygenated hyrdocarbons into hydrocarbons removing the oxygen as carbon oxides and water. A portion of the pyrolysis gases is condensed to produce low oxygen biomass-derived pyrolysis oil.

Nicholas, Christpher P; Boldingh, Edwin P

2013-12-17

460

Invisible fingerprints Spray bottle  

E-print Network

Invisible fingerprints Procedure Material