Synthesis and characterization of β-Sialon powders from Si, halloysite clay and AlN powders

Two [Formula: see text]-Sialons, with [Formula: see text]-values of 1 and 4, respectively, were successfully synthesized by silicothermal reduction and nitridation method under 0.4 MPa nitrogen pressure. The effect of firing temperatures on the phase transformations and morphologies of [Formula: see text]-Sialons were analyzed by XRD and SEM. For [Formula: see text]-Sialons ([Formula: see text]), the product was finally composed of targeted [Formula: see text]-Sialon ([Formula: see text]) and secondary phase [Formula: see text]-Si3N4; for [Formula: see text], [Formula: see text]-Sialon ([Formula: see text]) was the main phase, and 15R-Sialon and [Formula: see text]-Al2O3 co-existed as secondary phases. A higher firing temperature is more beneficial for the phase transformations and crystal growth of [Formula: see text]-Sialons, however, the most suitable firing temperature was 1400[Formula: see text]C.

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Synthesis and Characterization of Mg Doped ZnO and Importance of Secondary Phases

Journal of Nanoscience and Technology ◽

10.30799/jnst.255.19050406 ◽

2019 ◽

Vol 5 (4) ◽

pp. 765-768 ◽

Cited By ~ 1

Author(s):

V. Saraswathi ◽

R. Ramasamy ◽

R. Ramanathan

Keyword(s):

Synthesis And Characterization ◽

Secondary Phases ◽

Doped Zno ◽

Mg Doped

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Synthesis and characterization of sulfonated polymethylsiloxane polymer as template for crystal growth of CaCO3

Colloid & Polymer Science ◽

10.1007/s00396-008-1974-z ◽

2008 ◽

Vol 287 (4) ◽

pp. 385-393 ◽

Cited By ~ 15

Author(s):

Andrónico Neira-Carrillo ◽

Ranjith Krishna Pai ◽

M. Soledad Fernández ◽

Esteban Carreño ◽

Patricio Vasquez Quitral ◽

...

Keyword(s):

Crystal Growth ◽

Synthesis And Characterization

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Synthesis and Characterization of Mechanically Alloyed, Nanostructured Cubic MoW Carbide

Applied Sciences ◽

10.3390/app10249114 ◽

2020 ◽

Vol 10 (24) ◽

pp. 9114

Author(s):

Martin Martinez Ruiz ◽

Jesús Noé Rivera Olvera ◽

Rodolfo Morales Davila ◽

Leonardo González Reyes ◽

Vicente Garibay Febles ◽

...

Keyword(s):

Electron Microscopy ◽

Heavy Oil ◽

Ball Mill ◽

Secondary Phase ◽

High Energy ◽

Industrial Applications ◽

Synthesis And Characterization ◽

Nominal Composition ◽

Energy Ball

Carbides are used extensively as cutting tools, forming dies, and recently in catalysis applications, among other industrial applications. In this work, the synthesis and characterization of a nanostructured MoW bimetallic carbide were carried out by mechanical alloying with a mixture of elemental powders with a nominal composition of W1.5Mo6C2.5 at different grinding times as follows: 25, 50, and 75 h in a low-energy ball mill at a speed of 500 rpm and 125 and 150 h in a high-energy ball mill at a speed of 1500 rpm. The formation of a solid solution was observed at 150 h of milling; the nanostructured bcc MoW carbide corresponded to the main phase in the sample, besides the presence of the nanostructured MoW alloy as a secondary phase with an average crystal size of 40.8 nm. The phases and morphology at every stage of milling were studied by: X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), and Vickers hardness. As the milling time increased, the hardness of these particles increased from 10.5 to 31.48 GPa for the powder particles milled for 150 h. The samples obtained at 125 and 150 h of milling were evaluated during catalytic aqua-thermolysis of heavy oil to analyze fuel desulfurization properties by Fourier transform infrared (FTIR) techniques. The results showed the breaking of S-S bonds, indicating the existence of a desulfurization reaction of heavy oil.

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Adventures in Crystal Growth: Synthesis and Characterization of Single Crystals of Complex Intermetallic Compounds

Chemistry of Materials ◽

10.1021/cm2019873 ◽

2011 ◽

Vol 24 (3) ◽

pp. 409-420 ◽

Cited By ~ 71

Author(s):

W. Adam Phelan ◽

Melissa C. Menard ◽

Michael J. Kangas ◽

Gregory T. McCandless ◽

Brenton L. Drake ◽

...

Keyword(s):

Crystal Growth ◽

Single Crystals ◽

Intermetallic Compounds ◽

Synthesis And Characterization

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Synthesis and characterization of phosphocitric acid, a potent inhibitor of hydroxylapatite crystal growth

Biochemistry ◽

10.1021/bi00550a039 ◽

1980 ◽

Vol 19 (9) ◽

pp. 1983-1988 ◽

Cited By ~ 62

Author(s):

W. P. Tew ◽

C. Mahle ◽

J. Benavides ◽

J. E. Howard ◽

A. L. Lehninger

Keyword(s):

Crystal Growth ◽

Potent Inhibitor ◽

Synthesis And Characterization

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Oxygen Anion Solubility as a Factor in Molten Flux Crystal Growth, Synthesis, and Characterization of Four New Reduced Lanthanide Molybdenum Oxides: Ce4.918(3)Mo3O16, Pr4.880(3)Mo3O16, Nd4.910(3)Mo3O16, and Sm4.952(3)Mo3O16

Crystal Growth & Design ◽

10.1021/acs.cgd.6b00201 ◽

2016 ◽

Vol 16 (8) ◽

pp. 4225-4231 ◽

Cited By ~ 7

Author(s):

Anthony J. Cortese ◽

Dileka Abeysinghe ◽

Branford Wilkins ◽

Mark D. Smith ◽

Vitaly Rassolov ◽

...

Keyword(s):

Crystal Growth ◽

Synthesis And Characterization ◽

Molybdenum Oxides ◽

Oxygen Anion ◽

Molten Flux

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Microstructural Characterization of U Coprecipitated Phases Formed in Bentonic-Granitic Groundwater and under Anoxic Conditions

MRS Proceedings ◽

10.1557/proc-985-0985-nn02-08 ◽

2006 ◽

Vol 985 ◽

Author(s):

Javier Quinones ◽

Eduardo Iglesias ◽

Jose M. Cobo ◽

Aurora Martinez Esparza ◽

Jose Maria Gomez de Salazar

Keyword(s):

Dissolution Rate ◽

Iron Powder ◽

Microstructural Characterization ◽

Secondary Phase ◽

Radiation Shielding ◽

Localized Corrosion ◽

Spent Fuel ◽

Secondary Phases ◽

Anoxic Conditions

AbstractFor improving the accuracy of the performance assessment studies related to the spent fuel safety under storage conditions it is necessary to develop a new matrix alteration model. These models must be based on laboratory experiences and they should be capable to extrapolate to storing environmental conditions. Most of recently models developed included the oxidation and dissolution process of the spent fuel matrix, but the influence of a possible process of secondary phase formation over the spent fuel surface is not taken into account yet. This is a key process that could produce a reduction of the matrix dissolution rate, radiation shielding behaviour; however, the surface precipitation of the secondary phase could induce a localized corrosion process, which in this case dissolution rate of the spent fuel would be increased. This paper is focussed on microstructural characterization of secondary phases formed in coprecipitation experiments performed under anoxic conditions in granitic-bentonitic simulated groundwater. In order to simulate the influence of the container material, the coprecipitation experiments were performed in absence and presence of iron powder. The solid phases formed were characterized using the following techniques: XRD; SEM-EDX and TEM-EDX. The XRD diffraction pattern showed that under anoxic conditions a mixture of phases were obtained (sodium and potassium uranate and schoepite), whereas uranate phases were detected when only iron was present. The characterization study indicates that the U secondary phase formed (under reducing conditions and presence of iron powder) growth from iron surface. The crystal size of the secondary phase is independent of the presence of iron powder (and it is always less than 3 μm). Furthermore, the microstructural study showed the growing of U phases over iron powder.

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