Processing and properties of pure antiferromagnetic h-YMnO3

Yttrium manganite (YMnO3) is widely investigated multiferroic material with potential use in many technological applications. In this paper, we report on the preparation and characterization of multiferroic hexagonal YMnO3 ceramics obtained by chemical synthesis route. Precursor powders were prepared by the polymerizable complex method from citrate precursors. After calcination at 900?C the powders contained mixture of Y-Mn-O phases which were further sintered at different temperatures. XRD analysis revealed that sintering at 1400?C resulted in the formation of pure hexagonal YMnO3. Density of the obtained ceramics was 96%TD. The ceramic samples proved to have multiferroic properties - they are antiferromagnetic below 42K with linear dependence of magnetization as a function of applied magnetic field. The ferroelectric measurements performed at room temperature showed remanent polarization of 0.21 ?C/cm2 and the coercive field of 6.0 kV/cm for the YMnO3 sample sintered at 1400?C. The magnetization curves measured at 2 and 5 K for the powder samples calcined at 900?C and ceramic samples sintered at 1300?C exhibited a hysteresis loop due to a small concentration of Mn3O4 in the samples.

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CHARACTERIZATION OF HYDROXYAPATITE/TI6AL4V COMPOSITE POWDER UNDER VARIOUS SINTERING TEMPERATURE

Jurnal Teknologi ◽

10.11113/jt.v75.5168 ◽

2015 ◽

Vol 75 (7) ◽

Cited By ~ 2

Author(s):

Amir Arifin ◽

Abu Bakar Sulong ◽

Norhamidi Muhamad ◽

Junaidi Syarif

Keyword(s):

Mechanical Properties ◽

Composite Powder ◽

Sintering Temperature ◽

Physical And Mechanical Properties ◽

Xrd Analysis ◽

X Ray Diffraction ◽

Different Temperatures ◽

Two Phases ◽

Work Interaction

Hydroxyapatite (HA) has been widely used in biomedical applications due to its excellent biocompatibility. However, Hydroxyapatite possesses poor mechanical properties and only tolerate limited loads for implants. Titanium is well-known materials applied in implant that has advantage in mechanical properties but poor in biocompatibility. The combination of the Titanium alloy and HA is expected to produce bio-implants with good in term of mechanical properties and biocompatabilty. In this work, interaction and mechanical properties of HA/Ti6Al4V was analyzed. The physical and mechanical properties of HA/Ti6Al4V composite powder obtained from compaction (powder metallurgy) of 60 wt.% Ti6Al4V and 40 wt.% HA and sintering at different temperatures in air were investigated in this study. Interactions of the mixed powders were investigated using X-ray diffraction. The hardness and density of the HA/Ti6Al4V composites were also measured. Based on the results of XRD analysis, the oxidation of Ti began at 700 °C. At 1000 °C, two phases were formed (i.e., TiO2 and CaTiO3). The results showed that the hardness HA/Ti6Al4V composites increased by 221.6% with increasing sintering temperature from 700oC to 1000oC. In contrast, the density of the composites decreased by 1.9% with increasing sintering temperature.

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Characterization of Type B Carbonate Apatite Sintered Bodies

MRS Proceedings ◽

10.1557/opl.2011.196 ◽

2011 ◽

Vol 1301 ◽

Cited By ~ 1

Author(s):

N. Watanobe ◽

T. Yoshioka ◽

T. Ikoma ◽

T. Kuwayama ◽

T. Higaki ◽

...

Keyword(s):

Dissolution Kinetics ◽

Carbonate Apatite ◽

Artificial Bone ◽

Type B ◽

Desorption Process ◽

Different Temperatures ◽

Acidic Conditions ◽

Kinetics Of ◽

Potential Use

ABSTRACTThe dissolution kinetics of type B carbonate apatite (CAp) disks sintered at different temperatures were investigated under acidic conditions similar to an osteoclastic desorption process in bone remodeling. The type B CAp disks, which were uniaxially pressed at 98MPa and sintered at temperatures of 600 to 700 ºC, showed single crystalline phase and a high relative density of 60-62 % compared to the stoichiometric density of 3.16g/cm3 of hydroxyapatite (HAp). The dissolution rate of type B CAp disks sintered at 650 ºC was 3.5 times faster than that of HAp disks at 650 ºC. These results indicate that the Type B CAp sintered disks show potential use as a biodegradable material for artificial bone.

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Low Temperature Synthesis and Characterization of CaO and MgO- Stabilized Nanocrystalline Tetragonal Zirconia by Citrate Gel Process

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.754 ◽

2008 ◽

Vol 368-372 ◽

pp. 754-757

Author(s):

Hasan Gocmez ◽

Hirotaka Fujimori

Keyword(s):

Single Phase ◽

Tetragonal Zirconia ◽

Xrd Analysis ◽

Complex Method ◽

X Ray Diffraction ◽

Transmission Electron ◽

Heat Treated ◽

Crystallite Sizes ◽

Citrate Gel Process

The citrate gel method, similar to the polymerized complex method, was used to synthesize homogenous tetragonal zirconia at 800oC and 1000oC. Nanocrystalline tetragonal single phase has been fully stabilized with 3, 7, 10 mol% CaO and 10, 15 mol% MgO at 800oC, respectively. In addition, the XRD analysis showed the absence of monoclinic phase after addition of 7 and 10 mol% CaO into zirconia-based solid solutions, which have been fully stabilized both 800oC and 1000oC. The crystallite sizes of the t-ZrO2 with 3, 7 and 10 mol% CaO at 1000oC were 32, 28 and 29nm, respectively. For ZrO2- x mol% MgO (x=3, 10, 15) solid solution, the crystallite sizes of samples at 800oC were less than 29nm, however it was increased up to 69nm at 1000oC. The prepared gel and subsequent heat-treated powders were characterized by X-ray diffraction (XRD), Raman spectroscopy and transmission electron microscopy (TEM) to get detail information regarding to differentiation of polymorphs of zirconia as well as formation of powders.

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Synthesis and characterization of asphalt composite precursors using amorphous rice husk silica

Cerâmica ◽

10.1590/0366-69132019653742497 ◽

2019 ◽

Vol 65 (374) ◽

pp. 194-199 ◽

Cited By ~ 1

Author(s):

S. Sembiring ◽

R. Situmeang ◽

Z. Sembiring

Keyword(s):

Rice Husk ◽

Xrd Analysis ◽

Decomposition Temperature ◽

X Ray Diffraction ◽

Rice Husk Silica ◽

X Ray ◽

Roof Material ◽

Silica Addition ◽

Potential Use

Abstract In this research, asphalt composites were produced by mixing asphalt with silica extracted from rice husk, with a ratio of asphalt to silica of 1:0, 1:1.7 and 1:2, and calcined at 150 °C. Development of structures was characterized using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), followed by differential thermal analysis (DTA/TGA). The FTIR results showed the presence of Si-OH, C=O, and C-H functional groups, which were associated with asphaltene, carbon, and silica, according to the XRD analysis. The results obtained also indicated the significant effect of rice husk silica addition on phase transformation of asphaltene into silica and carbon, while asphaltene molecules were practically undetected. The presence of silica and carbon resulted in increased decomposition temperature of the sample. Based on these characteristics, the samples were considered as a roof material, suggesting their potential use as a substitute for lightweight steel roof devices.

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Preparation and characterization of lead ruthenate based composite cathodes for SOFC applications

MRS Proceedings ◽

10.1557/proc-835-k8.10 ◽

2004 ◽

Vol 835 ◽

Cited By ~ 1

Author(s):

Vincenzo Esposito ◽

Enrico Traversa ◽

Eric D. Wachsman

Keyword(s):

Solid Oxide Fuel Cells ◽

Electrochemical Impedance ◽

Xrd Analysis ◽

Composite Electrodes ◽

X Ray Diffraction ◽

Chemical Route ◽

Composite Cathodes ◽

Different Temperatures ◽

Eis Measurements

ABSTRACTNanometric pyrochlore lead ruthenate (Pb2Ru2O6.5) powders were prepared using a new chemical route as a possible candidate for cathode materials in solid oxide fuel cells (SOFCs). Pb2Ru2O6.5 was mixed with yttria-stabilized zirconia (YSZ) and erbia-stabilized bismuth oxide (ESB) to fabricate porous composite electrodes. Pure pyrochlore or composite electrodes were deposited as thick films onto YSZ and ESB electrolytes. Powders and films were analyzed using X-ray diffraction (XRD) analysis and field emission scanning electron microscopy (FE-SEM). Electrochemical features of the electrodes were investigated using electrochemical impedance spectroscopy (EIS) measurements at different temperatures in air for symmetric cells. The composite electrodes were compared to single Pb2Ru2O6.5 phase electrodes to evaluate the effect on polarization of the addition of the pure ionic conductor phase in the electrodes.

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A Critical Review of the Characterization of Polyphenol–Protein Interactions and of Their Potential Use for Improving Food Quality

Current Pharmaceutical Design ◽

10.2174/1381612823666170202112530 ◽

2017 ◽

Vol 23 (19) ◽

pp. 2742-2753 ◽

Cited By ~ 21

Author(s):

Maria Rosa Perez-Gregorio ◽

Jesus Simal-Gandara

Keyword(s):

Food Quality ◽

Protein Interactions ◽

Critical Review ◽

Potential Use

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Synthesis and Characterization of Nanocrystalline ZnO Powders by a Direct Thermal Decomposition Route Using Zinc Nitrate Hexahydrate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.770.68 ◽

2013 ◽

Vol 770 ◽

pp. 68-71 ◽

Cited By ~ 1

Author(s):

Supphadate Sujinnapram ◽

Uraiphorn Termsuk ◽

Atcharawan Charoentam ◽

Sutthipoj Sutthana

Keyword(s):

Thermal Decomposition ◽

Crystallization Temperature ◽

Zinc Nitrate ◽

Zinc Nitrate Hexahydrate ◽

Absorption Peak ◽

Synthesis And Characterization ◽

Nitrate Hexahydrate ◽

Different Temperatures ◽

Zno Powders

The nanocrystalline ZnO powders were synthesized by a direct thermal decomposition using zinc nitrate hexahydrate as starting materials. The precursor was characterized by TG-DTA to determine the thermal decomposition and crystallization temperature which was found to be at 325 oC. The precursors were calcined at different temperatures of 400, 500, and 600°C for 4 h. The structure of the prepared samples was studied by XRD, confirming the formation of wurtzite structure. The synthesized powders exhibited the UV absorption below 400 nm (3.10 eV) with a well defined absorption peak at around 285 nm (4.35 eV). The estimated direct bandgaps were obtained to be 3.19, 3.16, and 3.14 eV for the ZnO samples thermally decomposed at 400, 500, and 600°C, respectively.

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Bark characterization of a commercial Eucalyptus urophylla hybrid clone in view of its potential use as a biorefinery raw material

Biomass Conversion and Biorefinery ◽

10.1007/s13399-020-01199-7 ◽

2021 ◽

Author(s):

Caroline J. Sartori ◽

Graciene S. Mota ◽

Fábio Akira Mori ◽

Isabel Miranda ◽

Teresa Quilhó ◽

...

Keyword(s):

Raw Material ◽

Hybrid Clone ◽

Eucalyptus Urophylla ◽

Potential Use

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Incidence and characterisation of Bacillus cereus bacteriophages from Thua Nao, a Thai fermented soybean product

BioMolecular Concepts ◽

10.1515/bmc-2021-0009 ◽

2021 ◽

Vol 12 (1) ◽

pp. 85-93

Author(s):

Wallapat Phongtang ◽

Ekachai Chukeatirote

Keyword(s):

Bacillus Cereus ◽

Food Industry ◽

Pathogenic Bacteria ◽

Morphological Analysis ◽

Food Poisoning ◽

Fermented Soybean ◽

Foodborne Pathogenic Bacteria ◽

Ph Range ◽

Potential Use

Abstract Bacillus cereus is considered to be an important food poisoning agent causing diarrhea and vomiting. In this study, the occurrence of B. cereus bacteriophages in Thai fermented soybean products (Thua Nao) was studied using five B. cereus sensu lato indicator strains (four B. cereus strains and one B. thuringiensis strain). In a total of 26 Thua Nao samples, there were only two bacteriophages namely BaceFT01 and BaceCM02 exhibiting lytic activity against B. cereus. Morphological analysis revealed that these two bacteriophages belonged to the Myoviridae. Both phages were specific to B. cereus and not able to lyse other tested bacteria including B. licheniformis and B. subtilis. The two phages were able to survive in a pH range between 5 and 12. However, both phages were inactive either by treatment of 50°C for 2 h or exposure of UV for 2 h. It should be noted that both phages were chloroform-insensitive, however. This is the first report describing the presence of bacteriophages in Thua Nao products. The characterization of these two phages is expected to be useful in the food industry for an alternative strategy including the potential use of the phages as a biocontrol candidate against foodborne pathogenic bacteria.

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