Characterization of Ni Nanopowders Produced by Electrical Explosion of Wire Technique

Nanosize nickel powders were successfully produced by electrical explosion of wire (EEW). In EEW, the nickel wire was discharged in a chamber filled with nitrogen or argon gas, and the produced powders were subsequently stabilized by air-passivation at room temperature for 2 h. X-ray diffraction only showed the nickel phase of FCC crystal structure, whereas TEM and XPS analyses showed the formation of a very thin oxide layer of NiO on the surface of particles. Particles were spherical in shape, and the mean particle size calculated by specific surface area was about 100 nm. The particle size decreased with increasing charging voltage and with increasing ambient gas pressure. Argon gas was more effective in producing finer particles than nitrogen gas.

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Preparation and Characterization of Lignin Powder Micronized by a Supercritical Antisolvent (SAS) Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.233-235.1642 ◽

2011 ◽

Vol 233-235 ◽

pp. 1642-1645 ◽

Cited By ~ 2

Author(s):

Qi Lu ◽

Yuan Gang Zu ◽

Lei Yang ◽

Xiu Hua Zhao ◽

Wen Jun Liu ◽

...

Keyword(s):

Particle Size ◽

Optimal Conditions ◽

Orthogonal Array Design ◽

X Ray Diffraction ◽

Array Design ◽

X Ray ◽

Mean Particle Size ◽

Supercritical Antisolvent ◽

The Mean

Nanoscale lignin was successfully prepared with a supercritical antisolvent (SAS) apparatus using acetone as a solvent and superciritical carbon dioxide as an antisolvent. Four factors were studied and optimized by a four-level orthogonal array design (OAD). According to analysis of variance, precipitation pressure had a significant effect on mean particle size. The optimal conditions are as follows: precipitation temperature 35 °C, precipitation pressure 30 MPa, temperature difference +10 °C and concentration of lignin solution 0.5 mg/mL. The micronized lignin under the optimal conditions was characterized by Scanning Electron Microscopy (SEM), Fourier-transform Infrared Spectroscopy (FTIR), Dynamic Light Scattering (DLS) and X-Ray Diffraction (XRD) analyses. The results showed the mean particle size of micronized lignin was 0.144 ± 0.03 μm and had no degradation. The solubility of micronized lignin was improved significantly in distilled water.

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Effect of Process on the Dielectric Properties of BaTiO3-Based X9R Ceramics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.906.18 ◽

2014 ◽

Vol 906 ◽

pp. 18-24 ◽

Cited By ~ 1

Author(s):

Bao Lin Zhang ◽

Bin Bin Zhang ◽

Ning Ning Wang ◽

Jing Ming Fei

Keyword(s):

Particle Size ◽

Dielectric Properties ◽

Milling Time ◽

Sintering Temperature ◽

Sintering Process ◽

X Ray Diffraction ◽

Sintered Ceramic ◽

X Ray ◽

Particle Size Analyzer

The effect of milling time and sintering process on the dielectric properties of BaTiO3-based X9R ceramics was investigated. The characterization of the raw powders and the sintered ceramic was carried out by X-ray diffraction and scanning electron microscopy. The particle size distribution of the mixed powders was examined by Laser Particle Size Analyzer. The results shown that with the milling time extended, the Cruie Peak was depressed, or even disappeared. Moreover, with the rise of sintering temperature, the dielectric constant of the ceramics increased and the dielectric loss decreased gradually. Eventually, by milling for 11h and sintering at 1090°Cfor 2h, good dielectric properties were obtained, which were ε25°C≥ 2526, εr/εr25°C≤± 12% (–55~200°C), tanδ≤1.12% (25°C).

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Synthesis of Silver Nanoparticles Using Muntingia Calabura L. Leaf Extract as Bioreductor and Applied as Glucose Nanosensor

Oriental Journal Of Chemistry ◽

10.13005/ojc/340652 ◽

2018 ◽

Vol 34 (6) ◽

pp. 3088-3094 ◽

Cited By ~ 6

Author(s):

Abdul Wahid Wahab ◽

Abdul Karim ◽

Nursiah La Nafie ◽

Nurafni Nurafni ◽

I. Wayan Sutapa

Keyword(s):

Particle Size ◽

Silver Nanoparticles ◽

Reduction Method ◽

Measurement Range ◽

Structure Characterization ◽

X Ray Diffraction ◽

X Ray ◽

Particle Size Analyzer ◽

Muntingia Calabura

Silver nanoparticles have been synthesized by reduction method using extract of Muntingia calabura L. leaf a bioreductor. The process of silver nanoparticles formation was monitored by UV-Vis method. The results showed that the absorbance values increased according to the increase of reaction time. Maximum absorption of silver nanoparticle was obtained at a wavelength of 41-421 nm. The size of silver nanoparticles was determined using a PSA (Particle Size Analyzer) with a particle size distribution of 97.04 nm. The functional groups compound that contribute in the synthesis was analyzed using Fourier Transform Infrared Spectroscopy (FTIR). Morphology of the silver nanoparticles was observed by an Scanning Electron Microscope instrument and the structure characterization of the compounds were analyzed using X-Ray Diffraction. The glucose nanosensor based on silver nanoparticles have the measurement range of 1 mM - 4 mM with the regretion (R2) is 0,9516, the detection limit of sensor is 3,2595 mM, the sensitivity of sensor is 2,0794 A. mM-1. mM-2.

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Synthesis and Characterization of Surface Protected Nanocrystalline Particles of Titania

MRS Proceedings ◽

10.1557/proc-519-329 ◽

1998 ◽

Vol 519 ◽

Cited By ~ 1

Author(s):

E. Scolan ◽

C. Sanchez

Keyword(s):

X Ray Diffraction ◽

Elastic Light Scattering ◽

Titanium Butoxide ◽

X Ray ◽

Toluene Sulfonic Acid ◽

Nanocrystalline Particles ◽

Mean Size ◽

The Mean ◽

Cp Mas Nmr

AbstractMonodisperse non-aggregated nanoparticles of titania are obtained through hydrolysis at 60°C of titanium butoxide in the presence of acetylacetone and para-toluene sulfonic acid. After drying the resulting xerosols can be dispersed without aggregation in water-alcoholic or alcoholic solutions. The characterizations of the nanoparticles have been carried out by using quasi-elastic light scattering (QELS), 13C 1H in solution and X-ray diffraction, TEM, TG-DTA, 13C CP-MAS NMR in the solid state. The mean size of the anatase oxide core can be adjusted in the I to 5 nanometer range by a careful tuning of the synthetic conditions. The anatase particles are surrounded by acetylacetonato ligands, para-toluene sulfonate based species and water.

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Thermal and Structural Characterization of Nanocomposite Iron Nitride - Alumina and Iron Nitride - Silica Particles

MRS Proceedings ◽

10.1557/proc-703-v9.16 ◽

2001 ◽

Vol 703 ◽

Author(s):

Ann M. Viano ◽

Sanjay R. Mishra

Keyword(s):

Particle Size ◽

Milling Time ◽

Iron Nitride ◽

X Ray Diffraction ◽

X Ray ◽

Thermal Peak ◽

Transmission Electron ◽

Diffraction Patterns ◽

The One

ABSTRACTNanocomposite iron nitride based powders are known to have enhanced magnetic and other physical properties. To further explore their potential for application in various fields, we have performed a systematic study of the iron nitride - alumina and iron nitride - silica systems. Iron nitride powder of composition FexN (2 < x < 4), containing both Fe3N and Fe4N phases, was mechanically milled with Al2O3 or SiO2 powder for 4, 8, 16, 32, and 64 hours at the following compositions; (FexN)0.2(Al2O3)0.8, (FexN)0.6(Al2O3)0.4, (FexN)0.2(SiO2)0.8, and (FexN)0.6(SiO2)0.4. Differential thermal analysis and X-ray diffraction were performed to investigate thermal and structural transitions as a function of milling time. As the milling time is increased, the thermal peak corresponding to Fe4N is diminished, while the one corresponding to Fe3N is enhanced. These transitions are correlated with X-ray diffraction patterns. All XRD peaks broaden as a function of milling time, corresponding to smaller particle size. Transmission electron microscopy also reveals a decrease in particle size as the milling time in increased.

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Characterization of Clay from Vale do Mulembá - ES

Materials Science Forum ◽

10.4028/www.scientific.net/msf.591-593.487 ◽

2008 ◽

Vol 591-593 ◽

pp. 487-492 ◽

Cited By ~ 1

Author(s):

Monica Castoldi Borlini Gadioli ◽

J.C.G. Correia ◽

A. Caranassios

Keyword(s):

Particle Size ◽

Chemical Analysis ◽

Thermal Analyses ◽

The Other ◽

High Plasticity ◽

X Ray Diffraction ◽

X Ray ◽

Characterization Studies ◽

And Behavior

This work has for objective to characterize the clay from Vale do Mulembá-ES. The Vale do Mulembá is located in Joana D´Arc, Vitória in Espírito Santo State, Brazil. That clay is used in the production of the traditional clay pans of the State, what contributes to the economy of the area. The clay from Vale do Mulembá presents characteristics and behavior different from the other clays used for the production of clay pans. The characterization studies were carried out through chemical analysis, X-ray diffraction, particle size distribution, plasticity and thermal analyses (DTA, TGA). The results showed that the clay is typical kaolinitic, present relatively to the amount high of Al2O3 and high plasticity.

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Synthesis, Spectroscopic and X-Ray Structural Characterization of [Cd(linpen)]2+, a Model for Metal Complexes of the Chelating Polymer Polyethyleneimine (linpen = Linear Pentaethylenehexamine)

Zeitschrift für Naturforschung B ◽

10.1515/znb-1992-0612 ◽

1992 ◽

Vol 47 (6) ◽

pp. 829-836 ◽

Cited By ~ 2

Author(s):

Henry Strasdeit

Keyword(s):

Metal Ion ◽

X Ray Diffraction ◽

Linear Isomer ◽

X Ray ◽

Chelating Polymer ◽

The Mean ◽

Hexadentate Ligand ◽

Solid Compounds ◽

Strong Distortion

The isolation of 3,6,9,12-tetraazatetradecane-1,14-diamine (linear isomer of pentaethylenehexamine, linpen) from a technical polyamine mixture is described. In methanol, linpen acts as a hexadentate ligand towards cadmium(II). The solid compounds [Cd(linpen)](BPh4)2 (1), [Cd(linpen)](BPh4)2•2 DMSO (2) and [Cd(linpen)](BF4)2 (3) have been isolated and characterized by elemental analysis, spectroscopy and X-ray powder diffraction. The 113Cd NMR resonance of 1 is at 351 ppm (0.30 M in DMSO-d6, standard: 0.10 M Cd(ClO4)2 in D2O).2 and 3 have been structurally characterized by single-crystal X-ray diffraction. 2: C 2/c; a = 19.337(1)Å, b = 17.937(1)Å, c = 18.584(1)Å, β = 111.54(1)°; Z = 4, R = 0.034, Rw = 0.033.3: P21/n; a = 8.607(1)Å, b = 14.851(2)Å, c = 15.703(2)Å, ß = 91.21(2)°; Z = 4,R = 0.083, Rw = 0.072. Both compounds contain discrete [Cd(linpen)]2+ complexes. The hexamine wraps around the metal ion in a helical manner. This results in a strong distortion of the coordination polyhedron. The mean Cd-N bond lengths are 2.38Å and 2.37Å for 2 and 3, respectively.Models for MN6 centers in metal-polyethyleneimine (PEI) complexes are derived from the structure of [Cd(linpen)]2+. For example, loops at the MN6 site in molecules of linear PEI are proposed.

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Synthesis and Characterization of α-Phase Silicon Nitride Powders by Direct Nitridation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.631-632.434 ◽

2013 ◽

Vol 631-632 ◽

pp. 434-436

Author(s):

Jiu Ming Liu ◽

Jian Lei Wang ◽

Shu Xia Ren

Keyword(s):

Silicon Nitride ◽

Raw Materials ◽

X Ray Diffraction ◽

Nitrogen Gas ◽

Pure Nitrogen ◽

X Ray ◽

Α Phase ◽

Heat Treated ◽

Direct Nitridation

Using silicon powders as raw materials, adding nano-silicon nitride as a diluent and NH4Cl3 and FeCl3 as catalysts, α-phase silicon nitride powders were prepared by direct nitridation method. The silicon powders were first milled with 20% α-Si3N4 and 4% NH4Cl3 for 30 minutes. Then the mixture was heat-treated at 1300°C for 1 hour in the pure nitrogen gas. The phases and their content of the as-prepared product were detected by X-ray diffraction (XRD) and the microstructure was studied by scanning electron microscope (SEM). The results showed that the product mainly consisted ofα-Si3N4 with a mass fraction over 92% and were submicron-sized particles．

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