scholarly journals Design and Simulated Characteristics of Nanosized InSb Based Heterostructure Devices

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
T. D. Subash ◽  
T. Gnanasekaran ◽  
C. Divya ◽  
J. Jagannathan
Keyword(s):  
Particle Size ◽  
Indium Antimonide ◽  
Room Temperature ◽  
Average Particle Size ◽  
Average Particle ◽  
X Ray Diffraction ◽  
X Ray ◽  
Saturation Velocity ◽  
High Saturation ◽  
Heterostructure Devices

Indium antimonide nanoparticles were synthesized at room temperature. X-ray diffraction measurements are utilized to characterize the nanocomposites. The InSb nanoparticle has an average particle size in a range of 47 mm to 99 mm which is observed using the XRD result. The InSb is a material which is used to design the transistor. For designing purpose the simulator TCAD is used, by which the HEMT device is structured and its performance is analyzed and it is found that transistor operates as normal devices. This designed device is more valuable since a nanocomposite InSb material is used as a channel in HEMT device, thereby leading to the nanosized HEMT device. In addition, InSb has the property of high saturation velocity and mobility which results in higher performance of the device than any other materials in III-V compounds.

X-Ray Diffraction Study of HCP Metals II. Line Broadening in Polycrystalline Zn and Mg Powder

1975 ◽  
Vol 30 (6-7) ◽  
pp. 825-830 ◽  
Author(s):  
N. C. Halder ◽  
E. E. Johnston
Keyword(s):  
Particle Size ◽  
Room Temperature ◽  
Average Particle Size ◽  
Average Particle ◽  
Line Broadening ◽  
X Ray Diffraction ◽  
Fault Probability ◽  
Growth Fault ◽  
X Ray ◽  
Prob Ability

Abstract Microstructures of polycrystalline hexagonal close packed (hep) Zn and Mg have been studied by x-ray diffraction line broadening analysis using the integral breadth method, and the Fourier coefficient method. For these two methods, several diffraction peaks were considered to obtain two suitable peak combinations. For the room temperature powder samples, the root mean square (rms) strain was observed to be extremely small. The particle size was anisotropic in both samples with the Zn powder showing more particle size variation than Mg. The average particle size for Zn was about 750 Å, which was over twice the average particle size of 295 Å observed in Mg. The two fault probabilities for Zn turned out to be negligible or zero. Mg, on the other hand, was found to have small, but definite fault probabilities. The deformation fault probability a was 4.5X10-4 and the growth fault prob-ability β was 6.5X10-4 . These results can be compared with the previous work of hep Cd at room temperature, which was found to have no growth fault probability β and a deformation fault prob-ability a amounting to 3X10-3 . This value is higher than that observed in Mg, because for Cd the two fault probabilities were obtained by neglecting the particle size of about 650 Å which actually did exist in the sample.

scholarly journals Thermal, Structural, and Physical Properties of Freeze Dried Tropical Fruit Powder

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
K. A. Athmaselvi ◽  
C. Kumar ◽  
M. Balasubramanian ◽  
Ishita Roy
Keyword(s):  
Particle Size ◽  
Physical Properties ◽  
Average Particle Size ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Tropical Fruit ◽  
X Ray ◽  
Freeze Dried ◽  
Fruit Powder ◽  
Lcr Meter

This study evaluates the physical properties of freeze dried tropical (guava, sapota, and papaya) fruit powders. Thermal stability and weight loss were evaluated using TGA-DSC and IR, which showed pectin as the main solid constituent. LCR meter measured electrical conductivity, dielectric constant, and dielectric loss factor. Functional groups assessed by FTIR showed presence of chlorides, and O–H and N–H bonds in guava, chloride and C–H bond in papaya, and chlorides, and C=O and C–H bonds in sapota. Particle size and type of starch were evaluated by X-ray diffraction and microstructure through scanning electronic microscopy. A semicrystalline profile and average particle size of the fruit powders were evidenced by X-ray diffraction and lamellar/spherical morphologies by SEM. Presence of A-type starch was observed in all three fruits. Dependence of electric and dielectric properties on frequency and temperature was observed.

DIELECTRIC PROPERTIES OF ULTRAFINE Zn-DOPED CaCu3Ti4O12 CERAMIC

2012 ◽  
Vol 02 (01) ◽  
pp. 1250007 ◽  
Author(s):  
LAXMAN SINGH ◽  
U. S. RAI ◽  
K. D. MANDAL ◽  
MADHU YASHPAL
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Room Temperature ◽  
Single Phase ◽  
Average Particle Size ◽  
Average Particle ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Sintered Powder

Ultrafine powder of CaCu2.80Zn0.20Ti4O12 ceramic was prepared using a novel semi-wet method. DTA/TG analysis of dry powder gives pre-information about formation of final product around 800°C. The formation of single phase was confirmed by X-ray diffraction analysis. The average particle size of sintered powder of the ceramic obtained from XRD and Transmission electron microscopy was found 59 nm and 102 nm, respectively. Energy Dispersive X-ray studies confirm the stoichiometry of the synthesized ceramic. Dielectric constant of the ceramic was found to be 2617 at room temperature at 1 kHz.

The concentration quenching of photoluminescence in Eu3+-doped La2O3

2013 ◽  
Vol 37 (1) ◽  
pp. 47-54 ◽  
Author(s):  
V. Đorđević ◽  
Ž. Antić ◽  
M. G. Nikolić ◽  
M. D. Dramićanin
Keyword(s):  
Room Temperature ◽  
Hexagonal Phase ◽  
Average Particle Size ◽  
Average Particle ◽  
X Ray Diffraction ◽  
X Ray ◽  
Maximum Lifetime ◽  
Transmission Electron ◽  
Lifetime Value ◽  
Kinetics Of

Abstract This work explores the influence of dopant concentration on photoluminescent emission and kinetics of Eu3+-doped (0.2−10 at.%) nanocrystalline lanthanumoxide powders. The X-ray diffraction analysis confirmed that all samples crystallize in La2O3 hexagonal phase with space group P3¯ m1. Transmission electron microscopy showed particles with non-uniform shape and diverse size distribution with an average particle size of (95 ± 5) nm. The room temperature photoluminescence spectra of all samples contain characteristic Eu3+ luminescence lines with the most pronounced red 5D0 →7F2 emission at about 626 nm. The maximum intensity of red emission is observed for the sample containing 5at.% of Eu3+ ions. The emission kinetics was recorded in the temperature range from 10K to 300 K. The maximum lifetime value of 0.98 ms obtained for the sample with 0.5at.% Eu3+ at room temperature increases up to 1.3ms at 10 K.

Synthesis and Characterization of High Density and Low Temperature Sintered Proton Conductor BaCe0.5Zr0.35In0.1Zn0.05O3-δ

2015 ◽  
Vol 1098 ◽  
pp. 104-109 ◽  
Author(s):  
Abul Kalam Azad ◽  
D.D.Y. Setsoafia ◽  
L.C. Ming ◽  
Iskandar Petra
Keyword(s):  
Particle Size ◽  
Average Particle Size ◽  
Proton Conductor ◽  
Solid State Reaction Method ◽  
Proton Conductors ◽  
Orthorhombic Symmetry ◽  
Average Particle ◽  
X Ray Diffraction ◽  
X Ray ◽  
Proton Uptake

Rare-earth-doped BaCeO3and BaZrO3electrolytes with perovskite structure have been studied extensively in developing proton conducting intermediate temperature SOFC. Acceptor doped alkaline earth cerates and zirconates have been thoroughly studied because of the great interest in their possible applications as solid proton conductors. The perovskite type proton conductor BaCe0.5Zr0.35In0.1Zn0.05O3-δwas prepared in the traditional solid state reaction method. The density of the sample obtained about 96% of the theoretical density after sintering at 1350 °C and X-ray diffraction study confirms the pure phase. Rietveld refinement of the neutron and X-ray powder diffraction data shows that this material crystallizes in the orthorhombic symmetry in the space group Pm3m. Particle size measurement shows that the average particle size is about 2.4 μm. The average thermal expansion at 894 °C was 9.49 x 10-6/°C. Thermogravimetric analysis (TGA) traces obtained for the sample on heating in wet air shows that the maximum proton uptake occurs from 595 °C.

scholarly journals Sargassum Influx on the Mexican Coast: A Source for Synthesizing Silver Nanoparticles with Catalytic and Antibacterial Properties

2021 ◽  
Vol 11 (10) ◽  
pp. 4638
Author(s):  
Jose Luis López-Miranda ◽  
Rodrigo Esparza ◽  
Marlen Alexis González-Reyna ◽  
Beatriz Liliana España-Sánchez ◽  
Angel Ramon Hernandez-Martinez ◽  
...  
Keyword(s):  
Particle Size ◽  
Silver Nanoparticles ◽  
Average Particle Size ◽  
Antibacterial Properties ◽  
Average Particle ◽  
X Ray Diffraction ◽  
X Ray ◽  
Experimental Parameters ◽  
First Time

This work reports, for the first time, the synthesis of silver nanoparticles using extracts of the species of Sargassum natans and Sargassum fluitans (AgNPs-S). Their antibacterial and catalytic properties are compared with silver nanoparticles obtained by chemical synthesis (AgNPs-C). The characterization of AgNPs-S and AgNPs-C was carried out using ultraviolet–visible spectroscopy (UV–Vis), dynamic light scattering (DLS), zeta potential, a scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis. The synthesis of silver nanoparticles using Sargassum extract was optimized through varying experimental parameters, such as the type of solvent used to prepare the extract, the volume of the extract, and the pH of the system. The most efficient sample (AgNPs-S) was prepared with a water–ethanol-based extract, using a 3:1 volumetric ratio of extract: a precursor salt with the addition of 1 mL of NaOH pH = 14. The AgNPs-C were spherical in shape, with an average particle size of 11.55 nm, while the AgNPs-S were polyhedral shaped, with an average particle size of 26.39 nm. The synthesized AgNPs-S were found to have significantly higher catalytic activity for the degradation of methylene blue and more effective antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa than AgNPs-C.

A powder x-ray diffraction study of a solution treated and ice brine quenched Al–14.25 at.% Li alloy

1991 ◽  
Vol 6 (4) ◽  
pp. 712-718 ◽  
Author(s):  
A.G. Fox ◽  
S.C. Fuller ◽  
C.E. Whitman ◽  
V. Radmilovic
Keyword(s):  
Particle Size ◽  
Volume Fraction ◽  
Average Particle Size ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Maximum Order ◽  
X Ray ◽  
Order And Disorder ◽  
Solution Treated ◽  
Transmission Electron

An x-ray diffractogram was generated from a powder sample of solution treated and ice brine quenched Al–14.25 at.% Li alloy. The Bragg reflections obtained were characteristic of a very-nearly fully ordered Al-rich L12 phase based on δ'Al3Li together with two very weak reflections associated with δAlLi. All the lines were significantly broadened due to particle size effects. The average particle size associated with the 100 L12 superlattice line was found to be 4.2 (3) nm and with the fundamental lines, 26.8 nm. A simple structure factor calculation indicated the volume fraction of ordered phase to be around 0.77, assuming that the lack of maximum order was due to the presence of disordered fcc AlLi solid solution. These results suggest that the microstructure of this as-quenched alloy comprises ordered regions of about 4 nm in size in a sea of disordered matrix with a very small amount of δAlLi present. This conclusion is in excellent agreement with recent small angle x-ray and transmission electron microscope studies on similar alloys and suggests that AlLi alloys which are ostensibly disordered at high temperatures go through a disorder-order transformation and then decompose into regions of order and disorder which are associated with a composition spinodal.

scholarly journals Structure and piezoelectric properties of cazro3-modified (K,Na,Li)(Nb,Sb)O3 ceramics prepared from powders synthesized by microwave heating

2019 ◽  
Vol 13 (4) ◽  
pp. 368-375
Author(s):  
Xingrui Li ◽  
Bingbing Fan ◽  
Haowei Jia ◽  
Xuewen Shi ◽  
Yilin Zhang ◽  
...  
Keyword(s):  
Particle Size ◽  
Microwave Heating ◽  
Piezoelectric Properties ◽  
Average Particle Size ◽  
Average Particle ◽  
X Ray Diffraction ◽  
X Ray ◽  
Dense Microstructure ◽  
Good Crystallinity ◽  
Short Time

CaZrO3-modified (K0.48Na0.48Li0.04)(Nb0.95Sb0.05)O3 (CZ-KNLNS) lead-free piezoelectric powders were synthesized by microwave method followed by conventional solid state sintering. Different amounts of CaZrO3 were added (i.e. x = 0, 0.02, 0.03, 0.04, 0.06 mol) and their effects on the crystal structure, microstructure, as well as the electrical properties, were investigated. The results showed that CZ-KNLNS powders could be obtained by microwave heating at a relatively low temperature and short time of 650 ?C and 10min, respectively. The obtained CZ-KNLNS powders have cubic structure and good crystallinity with average particle size of 300-700 nm. The particle size gradually decreases with the increase of CaZrO3 amount, indicating that addition of CaZrO3 inhibits the growth of the particles. The powders were further sintered at 1120 ?C for 4 h and CZ-KNLNS ceramics with homogeneous and highly dense microstructure were obtained. X-ray diffraction showed that, with increasing CaZrO3 content, the phase structure gradually changed from orthorhombic to rhombohedral, which can be considered as the coexistence zone of orthorhombic-rhombohedral (O-R) phase in the range of 0.03 < x < 0.06. The optimized content of CaZrO3 is x = 0.04, at which the CZ-KNLNS piezoelectric ceramics show good properties and maximum d33 = 201.2 pC/N and Kp = 36.8%.

scholarly journals Effect of the stirring speed on the struvite formation using the centrate from a WWTP

2019 ◽  
pp. 42-50 ◽  
Author(s):  
Carolina Gonzalez Morales ◽  
Miller Alonso Camargo-Valero ◽  
Francisco José Molina Pérez ◽  
Belén Fernández
Keyword(s):  
Particle Size ◽  
Wastewater Treatment Plants ◽  
Average Particle Size ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Mean Values ◽  
X Ray ◽  
Operational Conditions ◽  
Significant Difference ◽  
Speed Range

The formation of struvite (MgNH4PO4·6H2O) for nutrient recovery in wastewater treatment plants has been widely investigated; however, little attention has been paid to the effect of stirring speeds on the resulting particle size, which could affect its agronomic value as a slow-release fertilizer. In this study, struvite formation from the centrate of sewage digestate was performed under six stirring speeds (0, 100, 200, 300, 400, 500 rpm). The resulting struvite crystals were characterised using X-ray diffraction and scanning electron microscopy with energy dispersive X-ray spectroscopy. The average particle size of struvite crystals increased from 55 µm at 0 rpm to 127 µm at 100 rpm and 128 μm at 200 rpm.  Further increments in stirring speeds resulted in smaller crystal sizes. These results indicated that the largest particle size can be obtained at stirring speeds ranging from 100 to 200 rpm, equivalent to a velocity gradient between 79 and 188 s-1, as there was no statistically significant difference between mean values (t-test, p<0.05). The optimum stirring speed range reported herein can be used to set operational conditions for struvite crystallisation with the benefit of producing large crystals and reducing energy consumption in stirring tanks.

Synthesis and Characterization of Nickel Aluminate Spinel (NiAl2O4) Prepared from the Equilibrium Mixture of Al2O3 and NiO

2015 ◽  
Vol 797 ◽  
pp. 391-399
Author(s):  
Justyna Zygmuntowicz ◽  
Aleksandra Miazga ◽  
Łukasz Kamiński ◽  
Katarzyna Konopka
Keyword(s):  
Particle Size ◽  
Solid Phase ◽  
Average Particle Size ◽  
Equilibrium Mixture ◽  
Synthesis And Characterization ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Nickel Aluminate ◽  
X Ray

The aim of this study was to synthesis and characterization of nickel aluminate spinel (NiAl2O4) prepared of the equilibrium mixture of Al2O3 and NiO. The materials were produced by the solid phase synthesis. In the experiments the following powders were used: α-Al2O3 TM-DAR from Taimei Chemicals (Japan) of an average particle size 133 nm and density 3.96g/cm3 and NiO powder from Sigma-Aldrich of an average particle size 200 nm and density 6.67 g/cm3. The preliminary calcination was carried out at two temperatures: 1000°C and 1200°C. The final sintering of the samples were performed at 1600°C. The characteristics of the powder after calcination and sintered samples were performed using X-ray diffraction studies (XRD), energy dispersive X-ray analysis (EDS) and scanning electron microscopy (SEM). The study of composites confirmed the presence of nickel aluminate (NiAl2O4) in whole volume of the material.

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