Preparation of Nanocrystalline Ba-Cu-Si Clathrate Powders by Mechanical Milling Using a Process Control Agent

Nanostructured Ba-Cu-Si clathrate powders were synthesized by mechanical milling using different amounts of process control agent (PCA). We investigated systematically the effects of PCA on the phase constitution and crystallite size of nanopowders using X-ray diffraction (XRD) as well as the particle size and morphology by scanning electron microscopy (SEM). The PCA increases the powder yield by reducing the powder agglomeration. No detectable reaction occurred between the PCA and the clathrate phase, and thus the composition of the clathrate phase is unchanged after milling. Compared to the powders milled without PCA, the crystalline size of powders with PCA is reduced from about 70 to about 50 nm.

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Effect of Mechanical Milling on the Microstructure and Hydrogen Interaction of Both Mm-Ni and MmNi5-Ni Mixtures

Materials Science Forum ◽

10.4028/www.scientific.net/msf.570.72 ◽

2008 ◽

Vol 570 ◽

pp. 72-77

Author(s):

Marcelo R. Esquivel ◽

Gabriel Meyer

Keyword(s):

Electron Microscopy ◽

Mechanical Milling ◽

Milling Time ◽

X Ray Diffraction ◽

X Ray ◽

Hydrogen Interaction ◽

Size And Morphology ◽

Temperature Heating ◽

Evolution With Time ◽

Scanning Electron

Mechanical milling (MM) and a combination of MM and temperature heating were used to synthesize the intermetallic MmNi5 and a MmNi5-Ni mixture, respectively. The process evolution with time was analyzed by scanning electron microscopy (SEM) and X-ray diffraction (XRD). SEM was used to characterize size and morphology of particles in order to reveal the governing mechanisms during the milling of each system. X-ray diffraction (XRD) was utilized to determine strain and crystallite size changes introduced by milling. The effects of integrated milling time on the sorption properties of the MmNi5-Ni mixture were analyzed. Results were correlated to defects introduced into microstructure. A comparison of the final characteristics of alloys obtained in each case is also shown.

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Magnesium Nitrate as Additive for Synthesis of Mg(OH)2 Nanoparticles

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.198-199.99 ◽

2012 ◽

Vol 198-199 ◽

pp. 99-102

Author(s):

Qing Gang Kong ◽

Hai Yan Qian

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Low Temperature ◽

Magnesium Nitrate ◽

Crystal Phase ◽

X Ray Diffraction ◽

X Ray ◽

Size And Morphology ◽

Scanning Electron

Magnesium nitrate was used as additive for synthesis of Mg(OH)2 (MH) nanoparticles at low temperature (70°C). Mg(OH)2 nanoparticles have platelet-like structure and approximately 40-60nm in thicknesses. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were applied to characterize the crystal phase. The supersaturation degree of solution effects the size and morphology of MH nanoparticles.

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Solvothermal Synthesis and Characterization of Lithium Tantalate Nanoparticles

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.602-603.19 ◽

2014 ◽

Vol 602-603 ◽

pp. 19-22 ◽

Cited By ~ 1

Author(s):

Lin Qiang Gao ◽

Hai Yan Chen ◽

Zhen Wang ◽

Xin Zou

Keyword(s):

Electron Microscopy ◽

Solvothermal Synthesis ◽

Room Temperature ◽

Synthesis And Characterization ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Particle Size And Morphology ◽

Size And Morphology

Nanoscale LiTaO3 powders with perovskite structure were synthesized using the solvothermal technique with glycol as solvent at 240°C for 12h. The powders were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). XRD was used to elucidate room temperature structures using Rietveld refinement. The powders were pure single pervoskite phase with high crystallinity. FESEM and TEM were used to determine particle size and morphology. The average LiTaO3 grain size was estimated to be < 200nm, and TEM images indicated that LiTaO3 particles had a brick-like morphology. In addition, the effect of the temperature on the LiTaO3 power characterisitics was also detailed studied.

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Synthesis, Structure and Properties of Super Fine LiMn2O4

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.177.9 ◽

2010 ◽

Vol 177 ◽

pp. 9-11 ◽

Cited By ~ 1

Author(s):

Jie Song ◽

Bing Xu ◽

De Xin Huang ◽

Cai Xia Li ◽

Qiang Li

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Particle Size ◽

Electrode Material ◽

Structure And Properties ◽

X Ray Diffraction ◽

Mechanochemical Method ◽

X Ray ◽

Size And Morphology ◽

Scanning Electron

In this paper, super fine LiMn2O4 powder was synthesized by mechanochemical method starting from Li2CO3 and Mn2O3. The structure, size and morphology of LiMn2O4 were explored with X-ray diffraction and scanning electron microscopy (SEM). The electrochemical properties of LiMn2O4 were studied in 2 mol/L (NH4)2SO4 solution. The result showed that pure spinel LiMn204 powder was prepared after 8h grinding with 3.0KW of power and the particle size was about 1µm. Cyclic vohammetry curve indicate LiMn2O4 electrode material has better capacitive performances.

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Synthesis of Macroporous FeS2 Nanotubes and their Electrochemical Properties

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.774-776.677 ◽

2013 ◽

Vol 774-776 ◽

pp. 677-681

Author(s):

Han Tao Liao ◽

You Rong Wang ◽

Jia Wang ◽

Xiao Fang Qian ◽

Si Qing Cheng

Keyword(s):

Electron Microscopy ◽

Electrochemical Properties ◽

X Ray Diffraction ◽

Capacity Retention ◽

One Pot ◽

X Ray ◽

Transmission Electron ◽

Particle Size And Morphology ◽

Size And Morphology ◽

First Time

The particle size and morphology have a strong influence on the electrochemical performance of FeS2electrodes. In this paper, a simple one-pot solvothermal method is reported for the synthesis of macroporous pyrite nanotubes for the first time. The phase composition, morphology and structure of the as-obtained products were studied by the energy dispersive spectroscopy (EDS), scanning electron microscopy, (high-resolution) transmission electron microscopy, X-ray diffraction. The electrochemical properties of the FeS2samples were also investigated. The results demonstrated that the macroporous pyrite nanotubes delivered a higher initial discharge capacity of 925.2 mAh g-1and had good capacity retention.

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Simple Thermal Decompose Method for Synthesis of Nickel Disulfide Nanostructures

High Temperature Materials and Processes ◽

10.1515/htmp-2015-0169 ◽

2016 ◽

Vol 35 (10) ◽

pp. 1017-1019 ◽

Cited By ~ 1

Author(s):

Hamideh Seyghalkar ◽

Mohammad Sabet ◽

Masoud Salavati-Niasari

Keyword(s):

Nickel Complex ◽

Steric Effect ◽

X Ray Diffraction ◽

Xrd Pattern ◽

X Ray ◽

Surface Purity ◽

Ft Ir ◽

Particle Size And Morphology ◽

Size And Morphology ◽

Scanning Electron

AbstractIn this work, a simple thermal decompose method was served to synthesize NiS2 nanostructures via a nickel complex. Also polyethylene glycol (PEG) was used as surfactant to increase the steric effect around nanostructure surfaces and decrease the particles size. The product was characterized with different analysis methods. The crystal structure of the product was studied by X-ray diffraction (XRD) pattern. The particle size and morphology were investigated by scanning electron microscopy (SEM). To study the nanostructures surface purity, Fourier transform infrared spectroscopy (FT-IR) was used. And finally to study the optical properties of the product photoluminescence (PL) spectroscopy was served.

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Synthesis, Structure and Properties of Super Fine Zn2SnO4

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.492.256 ◽

2011 ◽

Vol 492 ◽

pp. 256-259

Author(s):

Jie Song ◽

Cai Xia Li ◽

Dan Yu Jiang ◽

Jin Feng Xia ◽

Qiang Li

Keyword(s):

Electron Microscopy ◽

Organic Dye ◽

Structure And Properties ◽

X Ray Diffraction ◽

Mechanochemical Method ◽

Alizarin Red ◽

X Ray ◽

Bet Method ◽

Size And Morphology ◽

Scanning Electron

In this paper, super fine Zn2SnO4 powder was synthesized by mechanochemical method starting from ZnO and SnO2. The structure, size and morphology of Zn2SnO4were explored with X-ray diffraction (XRD), scanning electron microscopy (SEM) and nitrogen sorption analysis with the Brunauer-Emmett-Teller (BET) method. The result showed that pure spinel Zn2SnO4 powder was prepared after 2h grinding with 3.0KW of power and the particle size was about 200 nm. The degradation experiment of organic dye was performed by the photocatalytic methods on the light of wavelength (= 365nm). The powder can degrade Alizarin red solution close to 90% under U-V light with a 9W high.

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Identification of calcium oxalate crystals in dried or fixed tobacco leaf

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111550 ◽

1984 ◽

Vol 42 ◽

pp. 288-289

Author(s):

Vicki L. Baliga ◽

Mary Ellen Counts

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Calcium Oxalate ◽

Growth And Development ◽

Polarized Light ◽

Calcium Oxalate Crystals ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Scanning Electron

Calcium is an important element in the growth and development of plants and one form of calcium is calcium oxalate. Calcium oxalate has been found in leaf seed, stem material plant tissue culture, fungi and lichen using one or more of the following methods—polarized light microscopy (PLM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and x-ray diffraction.Two methods are presented here for qualitatively estimating calcium oxalate in dried or fixed tobacco (Nicotiana) leaf from different stalk positions using PLM. SEM, coupled with energy dispersive x-ray spectrometry (EDS), and powder x-ray diffraction were used to verify that the crystals observed in the dried leaf with PLM were calcium oxalate.

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Environmental scanning electron microscopy of fresh human gallstones reveals new morphologies of precipitated calcium salts

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131243 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1322-1323

Author(s):

Howard S. Kaufman ◽

Keith D. Lillemoe ◽

John T. Mastovich ◽

Henry A. Pitt

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Environmental Scanning Electron Microscopy ◽

Environmental Scanning ◽

X Ray Diffraction ◽

Calcium Salts ◽

Cholesterol Gallstones ◽

X Ray ◽

Ca Carbonate ◽

Scanning Electron

Gallstones contain precipitated cholesterol, calcium salts, and proteins. Calcium (Ca) bilirubinate, palmitate, phosphate, and carbonate occurring in gallstones have variable morphologies but characteristic windowless energy dispersive x-ray (EDX) spectra. Previous studies of gallstone microstructure and composition using scanning electron microscopy (SEM) with EDX have been limited to dehydrated samples. In this state, Ca bilirubinates appear as either glassy masses, which predominate in black pigment stones, or as clusters, which are found mostly in cholesterol gallstones. The three polymorphs of Ca carbonate, calcite, vaterite, and aragonite, have been identified in gallstones by x-ray diffraction, however; the morphologies of these crystals vary in the literature. The purpose of this experiment was to study fresh gallstones by environmental SEM (ESEM) to determine if dehydration affects gallstone Ca salt morphology.Gallstones and bile were obtained fresh at cholecystectomy from 6 patients. To prevent dehydration, stones were stored in bile at 37°C. All samples were studied within 4 days of procurement.

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Photocatalytic activity of TiO2 synthesized by anodization and anodic spark deposition

MRS Advances ◽

10.1557/adv.2020.405 ◽

2020 ◽

Vol 5 (61) ◽

pp. 3141-3152

Author(s):

Alma C. Chávez-Mejía ◽

Génesis Villegas-Suárez ◽

Paloma I. Zaragoza-Sánchez ◽

Rafael Magaña-López ◽

Julio C. Morales-Mejía ◽

...

Keyword(s):

Electron Microscopy ◽

Photocatalytic Activity ◽

Surface Characteristics ◽

Amorphous Solids ◽

X Ray Diffraction ◽

X Ray ◽

Catalytic Activities ◽

Anodic Spark Oxidation ◽

Porous Surfaces ◽

Scanning Electron

AbstractSeveral photocatalysts, based on titanium dioxide, were synthesized by spark anodization techniques and anodic spark oxidation. Photocatalytic activity was determined by methylene blue oxidation and the catalytic activities of the catalysts were evaluated after 70 hours of reaction. Scanning Electron Microscopy and X Ray Diffraction analysis were used to characterize the catalysts. The photocatalyst prepared with a solution of sulfuric acid and 100 V presented the best performance in terms of oxidation of the dye (62%). The electric potential during the synthesis (10 V, low potential; 100 V, high potential) affected the surface characteristics: under low potential, catalyst presented smooth and homogeneous surfaces with spots (high TiO2 concentration) of amorphous solids; under low potential, catalyst presented porous surfaces with crystalline solids homogeneously distributed.

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