Study of the mechanism for controlled crystallization of BaF2 under two kinds of monolayers

2001 ◽  
Vol 16 (8) ◽  
pp. 2415-2420 ◽  
Author(s):  
L. Lu ◽  
H. Cui ◽  
W. Li ◽  
H. Zhang ◽  
S. Xi
Keyword(s):  
Electron Microscope ◽  
Specific Interaction ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Degree Of Ionization ◽  
Detailed Mechanism ◽  
X Ray ◽  
Lattice Matching ◽  
Controlled Crystallization ◽  
Scanning Electron

Controlled crystallization of BaF2 under two different kinds of monolayers, octadecylamine [CH3(CH2)17NH2] and hexadecanol [CH3(CH2)14CH2OH], has been studied by using x-ray diffraction (XRD) and scanning electron microscope. It was found that the monolayer headgroup, the degree of ionization of the headgroup, etc., had a complicated effect on the selectivity of monolayers for crystal and on the morphology and orientation of crystals grown under the compressed monolayers. At pH = 7.0, XRD analysis showed that (100)-oriented BaF2 crystals were formed under the octadecylamine monolayer, while several kinds of crystals were found under the hexadecanol monolayer. In comparison, at pH = 8.5, both (100)-oriented BaF2 and (111)-oriented Ba(NO3)2 crystals were obtained under the monolayer of octadecylamine. However, crystals formed under hexadecanol monolayer consist of BaF2, Ba(NO3)2, etc. The detailed mechanism for crystallization was discussed in terms of the specific interaction and lattice matching between the monolayer headgroup and the nucleating species.

The Effect of CaCO3 Addition on Physical Properties of ZnO-Based Crystal Glaze

2012 ◽  
Vol 620 ◽  
pp. 12-16 ◽  
Author(s):  
Abdul Rashid Jamaludin ◽  
Shah Rizal Kasim ◽  
Zainal Arifin Ahmad
Keyword(s):  
Electron Microscope ◽  
Calcium Carbonate ◽  
Scanning Electron Microscope ◽  
Physical Properties ◽  
Crystallization Temperature ◽  
Xrd Analysis ◽  
Sem Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

The effects of calcium carbonate (CaCO3) addition on the physical properties of ZnO-based crystal glaze batches were investigated. Samples were fired at different gloss firing temperatures ranging from 1180-1220°C with 3 hours soaking at 1060°C crystallization temperature. X-ray diffraction (XRD) analysis identifiedthe crystal phase occurred as willemite (Zn2SiO4) and the scanning electron microscope (SEM) analysis indicated that willemite crystals are in the acicular needle like shape that formed spherulite. The intensities of willemite peaks decreased with CaCO3 addition and completely vanished at 5.0 wt% CaCO3. Varied formation of spherulites developed of the surface of crystal glaze as the flows of the glaze stretched further as the amount of CaCO3 increased.

Characterization of the Specificity in Three Commercial Dental Ceramic Powders

2017 ◽  
Vol 68 (4) ◽  
pp. 707-710
Author(s):  
Horia Manolea ◽  
Mirela Opri ◽  
Nicoleta Cioatera ◽  
Adriana Voinea ◽  
Radu Rica ◽  
...  
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
Sintered Material ◽  
Xrd Analysis ◽  
Dental Ceramics ◽  
X Ray Diffraction ◽  
Ceramic Powders ◽  
X Ray ◽  
Scanning Electron

The aim of this study was to present and discuss the characteristics of three ceramic powders as well as the sintered material from the three commercial dental ceramics produced by Vita Zahnfabrik, Germany (VM13 and VMK Master, used for veneering metal frameworks, respectivelly VM9 used for veneering zirconia frameworks). An X-ray diffraction (XRD) analysis was performed, Raman spectra were recorded and the morphology of the samples was evidenced by using a high resolution scanning electron microscope, equipped with an EDXS detector. The results of this study corroborated with the presented literature data helps practitioners to better understand the interaction of these biomaterials with oral tissues, and, also helps researchers to modify the properties of ceramics for a better integration in the intraoral condition.

EFFECT OF EXCESS BISMUTH ON THE SYNTHESIS OF BISMUTH SILICATE (Bi4Si3O12) POLYCRYSTALS

2009 ◽  
Vol 23 (08) ◽  
pp. 2093-2099 ◽  
Author(s):  
J. KAEWKHAO ◽  
N. UDOMKAN ◽  
W. CHEWPRADITKUL ◽  
P. LIMSUWAN
Keyword(s):  
Crystal Structure ◽  
Grain Size ◽  
Electron Microscope ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Bismuth Silicate ◽  
X Ray ◽  
Structure And Morphology ◽  
Crystallization Morphology ◽  
Scanning Electron

In this study, the effect of bismuth content on the crystal structure and morphology of bismuth silicate ( BSO:Bi 4 Si 3 O 12) polycrystals were investigated with X-ray diffraction (XRD) analysis and scanning electron microscope (SEM). BSO materials have been successfully prepared by the solid-state reaction. The BSO phase was crystallized at 950°C for 12 h. In summary, 10% of excess bismuth was found to be the optimum composition with respect to crystallization, morphology, and grain size.

The Characteristic of Surface Layers on Austenitic Stainless Steel after Glow-Discharge Nitriding Process

2010 ◽  
Vol 165 ◽  
pp. 165-168 ◽  
Author(s):  
Artur Sitko ◽  
Marek Szkodo ◽  
Maria Gazda
Keyword(s):  
Stainless Steel ◽  
Electron Microscope ◽  
Austenitic Stainless Steel ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Surface Layers ◽  
X Ray ◽  
Diffusion Layers ◽  
Chemical Constitution ◽  
Scanning Electron

This paper presents investigation of surface layers. The diffusion layers were produced by using different parameters of reactive atmosphere (N2:H2). The research of the surface layers was performed using scanning electron microscope (SEM). The results of energy dispersive X-ray (EDX) analysis and X-ray diffraction (XRD) analysis are presented. Research reveals the influence of chemical constitution of reactive atmosphere on the change of properties of nitrided layers.

CuO Microspheres Synthesized via the Easy Hydrothermal Method

2012 ◽  
Vol 159 ◽  
pp. 84-87
Author(s):  
Xiao Ming Fu
Keyword(s):  
Electron Microscope ◽  
Reaction Time ◽  
Scanning Electron Microscope ◽  
Hydrothermal Method ◽  
Xrd Analysis ◽  
Sem Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cuo Microspheres ◽  
Scanning Electron

CuO microspheres are successfully synthesized with CuCl2 as copper source and Na2CO3 as auxiliary salt at 240 °C for 24 h via the easy hydrothermal method. The phase and the morphologies of the samples have been characterized and analyzed by XRD (X-ray diffraction) and SEM (Scanning electron microscope), respectively. XRD analysis shows that the phase of as obtained samples is CuO. SEM analysis confirms that the increase of the reaction time, the reaction temperature and the auxiliary salt is propitious to synthesize CuO microspheres.

Synthesis of CuO Flower-Nanostructure via the Hydrothermal Method

2013 ◽  
Vol 873 ◽  
pp. 131-134
Author(s):  
Xiao Ming Fu ◽  
Jie Ren
Keyword(s):  
Electron Microscope ◽  
Reaction Time ◽  
Scanning Electron Microscope ◽  
Hydrothermal Method ◽  
Reaction Temperature ◽  
Xrd Analysis ◽  
Sem Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

CuO flower-nanostructures are successfully synthesized with CuCl2 as copper source and Na2CO3 as auxiliary salt at 180 °C for 24 h via the simple hydrothermal method. The phase and the morphologies of the samples have been characterized and analyzed by XRD (X-ray diffraction) and SEM (Scanning electron microscope), respectively. XRD analysis shows that the phase of as obtained samples is CuO. SEM analysis confirms that the increase of the reaction temperature is propitious to synthesize CuO flower-nanostructures while the increase of the reaction time is not in favor of their synthesis. The influence of the increase of the auxiliary salt on the morphology of CuO flower-nanostructures is not remarkable. The mechanism of the formation of CuO flower-nanostructure is discussed.

The Influence of the Hydrothermal Temperature on the Morphologies of β-Ni(OH)2 Nanospheres and Nanoflakes

2012 ◽  
Vol 159 ◽  
pp. 376-379 ◽  
Author(s):  
Xiao Ming Fu
Keyword(s):  
Electron Microscope ◽  
High Temperature ◽  
Scanning Electron Microscope ◽  
Xrd Analysis ◽  
Sem Analysis ◽  
X Ray Diffraction ◽  
Hydrothermal Temperature ◽  
X Ray ◽  
Low Reaction Temperature ◽  
Scanning Electron

β-Ni(OH)2 nanospheres and nanoflakes have been successfully synthesized with nickel nitrate as nickel source and stronger ammonia water as precipitant via the hydrothermal method. The phase and the morphologies of the samples have been characterized and analyzed by XRD (X-ray diffraction) and SEM (Scanning electron microscope), respectively. XRD analysis shows that the phase of the samples is β-Ni(OH)2. SEM analysis confirms that the low reaction temperature is propitious to the synthesis of β-Ni(OH)2 nanospheres. However, The high temperature is in favor of the synthesis of β-Ni(OH)2 nanosflakes.

scholarly journals Preparation, Physicochemical Characterization, and Bioactivity Evaluation of Strontium-Containing Glass Ionomer Cement

ISRN Ceramics ◽  
2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Masomeh Khaghani ◽  
Ali Doostmohammadi ◽  
Zahra Golniya ◽  
Ahmad Monshi ◽  
Ahmad Reza Arefpour
Keyword(s):  
Electron Microscope ◽  
Body Fluid ◽  
Glass Ionomer Cement ◽  
Xrd Analysis ◽  
Glass Ionomer Cements ◽  
Glass Ionomer ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ionomer Cement ◽  
Scanning Electron

Background. Glass ionomer cements are one of the most important restorative materials in dentistry. One of the disadvantages of glass ionomer cements is their undesirable mechanical properties and bioactivity. Aim. The aim of this work was preparation and characterization of strontium-containing glass ionomer cement and evaluation of its bioactivity in the simulated body fluid. Materials and Methods. The ceramic component of glass ionomer cement was made by melting method. Scanning electron microscope (SEM) was used to study the size and the shape of glass particles. In order to determine the phase combination in the produced material, X-ray diffraction (XRD) analysis was carried out. The chemical composition of the glass was evaluated by X-ray florescence (XRF), and the surface area of the particles was determined using BET method. In order to investigate the biological properties of the glass, samples were immersed in simulated body fluid (SBF). Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) were used to recognize and confirm the apatite layer on the composite surface. Results and Conclusions. The result of X-ray diffraction (XRD) analysis confirmed the glassy structure of the produced ionomer cements. The result of XRF confirmed the presence of Sr in the chemical composition. Fourier transform infrared spectroscopy test and electron microscope confirmed the formation of apatite layer on the surface of material. The final result of this research was gaining glass ionomer cement containing Sr with improved bioactivity.

Epitaxy in the Crystallization of Feldspar Gels and Glasses

1994 ◽  
Vol 346 ◽  
Author(s):  
Chunling Liu ◽  
Sridhar Komarneni ◽  
Rustum Roy
Keyword(s):  
Electron Microscope ◽  
Energy Dispersive Spectrometry ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Crystallization Product ◽  
X Ray ◽  
Seeding Effect ◽  
Before And After ◽  
Scanning Electron

ABSTRACTThe crystallization behaviors of stoichiometric feldspar gels and glasses before and after seeding have been compared, and the role of epitaxy in their crystallization upon seeding has been studied. The crystallization products were mainly determined by X-ray diffraction (XRD) analysis and epitaxy upon seeding was examined with a scanning electron microscope (SEM), and energy dispersive spectrometry (EDS). It was found that upon isostructural seeding, Na-and K-feldspars crystallized epitaxially from their gels and/or glasses. Little or no seeding effect was found in CaAl2Si2O8 and SrAl2Si2O8 gels and glasses. Isostructural seeding in BaAl2Si2O8 gels increased the formation of Ba-feldspar (monoclinic celsian) epitaxially, whereas without seeding hexacelsian was the crystallization product.

PENGGUNAAN TiO2 PARTIKEL NANO HASIL SINTESIS BERBASIS AIR MENGGUNAKAN METODA SOL-GEL PADA BAHAN KAPAS SEBAGAI APLIKASI UNTUK TEKSTIL ANTI UV

Arena Tekstil ◽  
2013 ◽  
Vol 28 (1) ◽  
Author(s):  
Maya Komalasari ◽  
Bambang Sunendar
Keyword(s):  
Fourier Transform ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Sol Gel ◽  
Crosslinking Agent ◽  
X Ray Diffraction ◽  
Nano Tio2 ◽  
X Ray ◽  
Infra Red ◽  
Scanning Electron

Partikel nano TiO2 berbasis air dengan pH basa telah berhasil disintesis dengan menggunakan metode sol-gel dan diimobilisasi pada kain kapas dengan menggunakan kitosan sebagai zat pengikat silang. Sintesis dilakukan  dengan prekursor TiCl4 pada konsentrasi 0,3 M, 0,5 M dan 1 M, dan menggunakan templat kanji dengan proses kalsinasi pada suhu 500˚C selama 2 jam. Partikel nano TiO2 diaplikasikan ke kain kapas dengan metoda pad-dry-cure dan menggunakan kitosan sebagai crosslinking agent. Berdasarkan hasil Scanning Electron Microscope (SEM),diketahui bahwa morfologi partikel TiO2 berbentuk spherical dengan ukuran nano (kurang dari 100 nm). Karakterisasi X-Ray Diffraction (XRD) menunjukkan adanya tiga tipe struktur kristal utama, yaitu (100), (101) dan (102) dengan fasa kristal yang terbentuk adalah anatase dan rutile. Pada karakterisasi menggunakan SEM terhadap serbuk dari TiO2 yang telah diaplikasikan ke permukaan kain kapas, terlihat adanya imobilisasi partikel nano TiO2 melalui ikatan hidrogen silang dengan kitosan pada kain kapas. Hasil analisa tersebut kemudian dikonfirmasi dengan FTIR (Fourier Transform Infra Red) yang hasilnya memperlihatkan puncak serapan pada bilangan gelombang 3495 cm-1, 2546 cm-1, dan 511 cm-1,  yang masing-masing diasumsikan sebagai adanya vibrasi gugus fungsi O-H, N-H dan Ti-O-Ti. Hasil SEM menunjukkan pula bahwa kristal nano yang terbentuk diantaranya adalah fasa rutile , yang berdasarkan literatur terbukti dapatberfungsi sebagai anti UV.

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