Diffraction Particle Size Analyzer Research Articles

A comprehensive study of Al-Cu-Mg system reinforced with nano-ZrO2 particles synthesized by powder metallurgy technique

More focus has recently been placed on enhancing the strength, elastic modulus, coefficient of thermal expansion (CTE), wear and corrosion resistance, and other qualities of aluminum (Al) alloys by varying the quantity of ceramics added for a range of industrial uses. In this regard, Al-4.2-Cu-1.6Mg matrix nanocomposites reinforced with nano-ZrO2 particles have been created using the powder metallurgy approach. The microstructure and particle size distributions of the produced powders were analyzed using a diffraction particle size analyzer, XRD, TEM, and SEM. To achieve good sinterability, the powders were compacted and sintered in argon. The sintered nanocomposites' mechanical, elastic, and physicochemical characteristics were measured. Additionally, the behavior of corrosion, wear, and thermal expansion were examined. The results showed a decrease in the particle sizes of the Al-Cu-Mg alloy by adding ZrO2 nanoparticles up to 45.8 nm for the composite containing 16 wt.% ZrO2. By increasing the sintering temperature to 570 °C, the densification of nanocomposites was enhanced. Also, the coefficient of thermal expansion and wear rate remarkably decreased by about 28 and 37.5% by adding 16 wt.% ZrO2. Moreover, microhardness yield, strength, and Young’s modulus were enhanced to 161, 145, and 64%, respectively, after adding 16 wt.% ZrO2. In addition, increasing the exposure time was responsible for decreasing the corrosion rate for the same sample.

Structural Characterization of Titanium-Silica Oxide Using Synchrotron Radiation X-ray Absorption Spectroscopy.

In this study, titania–silica oxides (TixSiy oxides) were successfully prepared via the sol–gel technique. The Ti and Si precursors were titanium (IV), isopropoxide (TTIP), and tetraethylorthosilicate (TEOS), respectively. In this work, the effects of pH and the Ti/Si atomic ratio of titanium–silicon binary oxide (TixSiy) on the structural characteristics of TixSiy oxide are reported. 29Si solid-state NMR and FTIR were used to validate the chemical structure of TixSiy oxide. The structural characteristics of TixSiy oxide were investigated using X-ray diffraction, XRF, Fe-SEM, diffraction particle size analysis, and nitrogen adsorption measurements. By applying X-ray absorption spectroscopy (XAS) obtained from synchrotron light sources, the qualitative characterization of the Ti–O–Si and Ti–O–Ti bonds in Ti–Si oxides was proposed. Some Si atoms in the SiO2 network were replaced by Ti atoms, suggesting that Si–O–Ti bonds were formed as a result of the synthesis accomplished using the sol–gel technique described in this article. Upon increasing the pH to alkaline conditions (pH 9.0 and 10.0), the nanoparticles acquired a more spherical shape, and their size distribution became more uniform, resulting in an acceptable nanostructure. TixSiy oxide nanoparticles were largely spherical in shape, and agglomeration was minimized. However, the Ti50Si50 oxide particles at pH 10.0 become nano-sized and agglomerated. The presence of a significant pre-edge feature in the spectra of Ti50Si50 oxide samples implied that a higher fraction of Ti atoms occupied tetrahedral symmetry locations, as predicted in samples where Ti directly substituted Si. The proportion of Ti atoms in a tetrahedral environment agreed with the value of 1.83 given for the Ti–O bond distance in TixSiy oxides produced at pH 9.0 using extended X-ray absorption fine structure (EXAFS) analysis. Photocatalysis was improved by adding 3% wt TiO2, SiO2, and TixSiy oxide to the PLA film matrix. TiO2 was more effective than Ti50Si50 pH 9.0, Ti50Si50 pH 10.0, Ti50Si50 pH 8.0, and SiO2 in degrading methylene blue (MB). The most effective method to degrade MB was TiO2 > Ti70Si30 > Ti50Si50 > Ti40Si60 > SiO2. Under these conditions, PLA/Ti70Si30 improved the effectiveness of the photocatalytic activity of PLA.

The Effect of Different Fly Ash and Vanadium Carbide Contents on the Various Properties of Hypereutectic Al-Si Alloys-Based Hybrid Nanocomposites

In the current work, a hybrid nanocomposite Al-Si matrix was fabricated using the powder metallurgy method. Due to their superior mechanical strength, formability, and durability, aluminum composite matrices have considered attractive materials for structural and advanced applications. The incorporation of fly ash (FA) as one of the cheapest and lowest density reinforcement available during the combustion process with high-density ceramic particles such as vanadium carbide (VC) has significant benefits in the production process of such composites. The hybridization of VC and FA nanoparticles with different weight percentages were used to reinforce the Al-Si matrix under various sintering conditions. A scanning electron microscopy (SEM) and diffraction particle size analyzer were utilized to examine the microstructure of the prepared powder and particle size. In addition to the mechanical and physical properties, the wear and corrosion resistance were investigated for the fabricated samples. The results revealed that the addition of 10 wt.% VC and 10 wt.% FA nanoparticles caused a decrease in the Al-Si alloy particle sizes up to 47.8 nm and act as a barrier for dislocation movement. Also, the microhardness, yield strength, and ultimate copressive strength were enhanced by 75, 42 and 38%, respectively. Moreover, there was an increase of about 25% in the ultrasonic longitudinal and shear velocities, thus showing a significant improvement in the elastic moduli group of about 50%. Finally, the addition of VC and FA particles significantly affected the wear and corrosion resistance; hence, they increased by 40 and 67%, respectively.

Facile Synthesis of Novel Parallelogram-Like NH4CoPO4 · H2O/Ni3(PO4)2 · 8H2O/MnO2 Composites for High-Performance Supercapacitors

Abstract To construct novel multicomponent transition metal oxides with the synergistic effect is always the most important strategy to improve the electrochemical performance of supercapacitor electrode materials. Here, a new type of parallelogram-like NH4CoPO4 · H2O/Ni3(PO4)2 · 8H2O/MnO2 (NNM) composites were successfully prepared by a simple hydrothermal method, and the addition amount of MnO2 was adjusted in detail. The morphology, structure, composition, particle size, and distribution of the electrode were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), Raman spectrum, and laser particle size analyzer. The results showed that when MnO2 was added at 9.7 wt%, the resulting NNM-9.7 composite exhibited a parallelogram-like morphology with an average length, width. and thickness of 5, 3, and 0.2 µm, respectively. The results of cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS) show that the NNM-9.7 electrode has large specific surface area, good conductivity, and abundant porosity, which makes it to have high-specific capacity (1180 F g−1, 1 A g−1) and excellent rate retention (980 F g−1, 10 A g−1) when compared with other electrodes, which is better than most reported electrodes of nickel–cobalt oxides/hydroxides. These results indicate that the novel NNM-9.7 composite with parallelogram-like shape and its synthesis method may provide a feasible solution for supercapacitors' material issues.

Bio-synthesized silver nanoparticles using Zingiber officinale rhizome extract as efficient catalyst for the degradation of environmental pollutants

Silver nanoparticles were synthesized through an eco-friendly process using an extract of Zingiber officinale rhizome. Spectrophotometric analysis of the AgNPs exhibited sharp band centered around 400–420 nm. The functionality of phytochemicals present in the Z. officinale was identified using FTIR spectroscopy. The characterization of synthesized AgNPs was done by UV-Vis spectroscopy, transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), and selected area electron diffraction pattern (SAED), particle size, and zeta potential analyzer. The average measured size and diameter of AgNPs were ∼20 nm, measured by XRD and TEM. We have successfully utilized the AgNPs as efficient catalyst in degradation of harmful dyes: methylene blue, methyl red, and safranin O. The rate constant for the degradation of dyes was found to be 14.25 × 10−3 sec−1, 9.68 × 10−3 sec−1 and 4.72 × 10−3sec−1 for methylene blue, methyl red, and safranin O respectively.

Modelos matemáticos de parámetros reológicos y su influencia en el sistema de bombeo de fluidos no newtonianos

En la presente investigación se realizó un estudio de la influencia de los parámetros reológicos de las hidromezclas lateríticas con los parámetros energéticos de los sistemas de bombeo que garantizan la productividad en la obtención de sulfuro de níquel. A partir de estudios experimentales como técnicas de difracción de rayos-X, fluorescencia de rayos-X y análisis de tamaño de partículas se modelaron los comportamientos de la viscosidad aparente, el esfuerzo cortante inicial, el índice de consistencia másica y el índice de flujo. Lo anterior, en función de los siguientes factores: temperatura, contenido de sólidos, composición química y granulométrica. Los resultados evidenciaron que las suspensiones lateríticas se comportan como flujos no newtonianos con plasticidad, debido a su carácter de materiales polidispersos, con un predominio de granulometría fina (partículas menores de 0,045 mm). Esto explica sus comportamientos reológicos, ajustables al modelo de Bulkley – Herschel a valores de temperatura de 28 a 90 °C y concentración de sólidos de 37 a 48% (p/p). Se concluye que el uso de un modelo matemático que relaciona los parámetros reológicos de la pulpa laterítica y los parámetros energéticos del sistema de bombeo contribuye con la eficiencia energética de la alimentación de la pulpa requerida en el proceso de lixiviación ácida.

Filling ratio of vial

The ratio effect of total volume of balls and powders with respect to volume of vial has not been deeply considered by the researchers for ball milling process. The importance of this new parameter for ball milling process, filling ratio of vial, was investigated in this study. For this purpose, Al–Fe2O3 thermite mixture was used as the starting materials. The powder masses input of 1, 5, 10, and 15 g were loaded into a steel-made vial with 150 cm3 capacity. Differential scanning calorimetry (DSC), scanning electron microscopy (SEM), X-ray diffraction (XRD), and laser particle size analysis (LPA) were used to evaluate the importance of FRV. The results indicated that by keeping constant all the parameters except FRV, various thermal analysis (DSC) results were obtained, showing the importance of this factor, while the same XRD patterns were revealed. It was found that the main exothermic reaction between Al and Fe2O3 occurred at various temperatures from 940 to 993 °C with various intensities. It was also revealed that for 10 g powder mass input, the reaction mechanism was changed, in which the reactions took place in three steps, before and after the melting of aluminum. The DSC curves were more discussed using SEM and LPA results, focused on morphology of the ball-milled powders. It was finally suggested that filling ratio of vial should be considered as an important factor in ball milling process.

Green-coloured pigments with perovskite structure

Samples were synthesised by solid-state reaction at high temperatures and characterised by X-ray diffraction analysis, colouristic analysis and particle size analysis. Possible MoO3 evaporation at high temperatures was studied by method of thermal analysis. The most interesting sample is SrO–0.65SnO2–0.05MoO3–0.075Tb4O7 which was prepared by calcination at 1500 °C. This powder is single phase, with cubic structure. Colour of the sample is dark green (L* = 46.37, b* = −9.630 and b* = 10.60).

The Effect of Ge on the Electrochemical Performance of Sn/C Nanocomposite Anode Materials for Lithium Ion Batteries

nanosized Sn-Ge/C composite powders were successfully prepared by rocking vibratory ball milling method, and characterized with X-ray powder diffraction and laser particle size analysis method. The electrochemical performance of the nanocomposite anodes was investigated by charge-discharge tests. The results show that Ge exhibits as the elemental form in the nanocomposites. The capacity of nanocomposite anodes can be enhanced by the introduction of micro-sized Ge powders. The Sn90Ge10/C nanocomposite anodes deliver the optimum electrochemical performance, including discharge capacity and cycling stability. However, the relatively fast capacity fade of the nanocompsoite anodes need to be further improved.

The Physicochemical Properties and the Fate of Fly Ash along the Air Pollution Control Devices in Coal-Fired Power Plant

The fly ash at the exit of inlet and outlet of No.2 ESP and outlet of No.2 FGD in San-he Power Plant were sampled. The microstructure, elemental composition, particle size distribution and other physicochemical properties of the collected ash samples were tested and analyzed by a scanning electron microscope (SEM), X-ray energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and Mastersizer2000 laser particle size analyzer. The results showed that, ESP outlet fly ash particle size distribution curve was significantly moved to the left, the proportion of the fine ash at the outlet was significantly increased compared with that of at the inlet, the morphology and composition of ash at the outlet of ESP, FGD was significantly changed compared to the ash at the inlet of ESP, indicating that air pollution control equipment (APCDs) have a great impact on physicochemical properties and the fate of fly ash.

Phase and particle of Y-doped Ni(OH)2 prepared from different nickel sources and Na2CO3 amount

Multiple nano-sized α-Ni(OH)2 was synthesized by ultrasonic-assisted precipitation under different conditions. The crystal structure and particle size distribution of the sample were characterized with X-ray diffraction (XRD), infrared spectroscopy, and laser particle size analyzer (PSA). The results show that the samples are anisotropic polycrystalline of α and β Ni(OH)2, and the ratio of α and β changes with the difference of nickel source, resulting in the largest ratio of α-Ni(OH)2 using nickel nitrate as reactant. Larger amount of Na2CO3 is conducive to the formation of α-Ni(OH)2; while the resultant phases are all β with the same conditions but no doping. The results of PSD indicate that the samples are about 100–120 nm in size, and the sample with nickel sulfate as nickel source has the minimum particle size. The three ions of nickel source appear in the absorption peaks in the Fourier transform infrared spectrum showing that the ions change the crystal structure of Ni(OH)2. EDS testing shows that Y and anion distribute in the lattice of α-Ni(OH)2 uniformly.

Influence of cetyltrimethylammonium bromide and sodium lauryl sulfate on production of zinc powders by alkaline electrowinning

The effects of cetyltrimethylammonium bromide (CTABr) and sodium lauryl sulfate (SLS) on the current efficiency, cell voltage, voltammetric behavior, and deposit character during production of zinc powder by alkaline electrowinning were investigated. Surface morphologies, crystallographic orientations, and grain size distributions of zinc powders were examined by Scanning Electron Microscopy, X-ray Diffraction, and Malvern Laser Particle Size Analyzer, respectively. Maximum current efficiencies of 97.5 and 98.3% were obtained at 1 mg/L CTABr and 10 mg/L SLS, respectively. Voltammetric studies indicated that the surfactants polarized the cathode, which was reflected in powder character. The surfactants dramatically changed the surface morphology and decreased the grain size. Zinc powders with an average grain size of 34.7 μm were obtained in the presence of 10 mg L−1 CTABr. At 0–10 mg L−1 CTABr/SLS, zinc powders exhibited an orientation dominated by (101) (002) (100). 1 mg L−1 SLS hadapositive effect on counteracting the influence of Sb.

Mechanism of Reduction in Grain and Particle Sizes of Nix-Fe100x Nanopowder by Mechanical Alloying

Ball milling with high energy for mechanical alloying was followed to make Ni-Fe alloy powders from elemental Ni and Fe powders having the sizes of 80 µm (Ni) and 25 µm (Fe). Preparations were carried out at room temperature with various duration of time ranging from 2 to 100 hours using ball milling with high energy. Analyses based on X-ray diffraction pattern and particle size analyzer were used for characterization of powders. During ball milling, it was observed that the reduction of grain size and particle size occurred in a stepped fashion. This observation indicates that the reduction in grain size and particle size occurs in a successive cyclic fashion, contrary to the expectation of concurrent reduction.

Preparation of Nano-TiO<sub>2</sub> in Inverse Microemulsion System with TiOSO<sub>4</sub> as Raw Material

The nanosized TiO2was prepared by microemulsion process in the system of cyclohexane/[Span80 combine with Tween40]/water with TiOSO4as raw material. The synthesis process of the powder was investigated by differential thermal analysis (DTA), X-ray diffraction (XRD) and laser particle size analysis (LPSA). The results showes that TiO2with the average size of 19.5nm and narrow size distribution was prepared under these conditions of Span80 of 8g and Tween40 of 2g as the emulsifier, water/oil mass ratio of 1/4, amount of TiOSO4of 10mL with the consistency of 0.8mol/L, calcination temperature of 480 °C for 20min.

Synthesis and Characterization of Al–SiC Nanocomposites Produced by Mechanical Milling and Sintering

Aluminum powder and various volume fractions of SiC particles with an average diameter of 50 nm were milled by a high-energy planetary ball mill to produce nanocrystalline Al–SiC nanocomposite powders. Double pressing/sintering process was used to consolidate powders to cylindrical specimens. It was shown that a double cycle of cold pressing and sintering can be utilized to obtain high density Al–SiC nanocomposite parts without using a hot-working step. High resolution scanning electron microscopy (HRSEM), X-ray diffraction (XRD) and laser particle size analyzer (PSA) were used to study the morphological and microstructural evolution of nanocomposite powders and bulk samples. The role of volume fraction of SiC nanoparticles in grain size of both as-milled and as-consolidated aluminum matrix was investigated. It was found that the presence of the higher SiC particles eventuate to slowly decrease in grain size of aluminum matrix powders. However, this trend is strongly noticeable in grain size of consolidated samples. The pinning effects on grain stability by SiC nanoparticles were quantitatively analyzed. It was found that Gladman's model is in close agreement with the experimentally determined grain size of Al–SiC nanocomposites.

Entrainment of lactose inhalation powders: A study using laser diffraction

We have investigated the mechanism of entrainment of lactose inhalation blends released from a dry powder inhaler using a diffraction particle size analyser (Malvern Spraytec). Whether a powder blend entrains as a constant stream of powder (the “erosion” mechanism) or as a few coarse plugs (the “fracture” mechanism) was found by comparing transmission data with particle size information. This technique was then applied to a lactose grade with 0, 5 and 10 wt% added fine particles. As the wt% fines increased, the entrainment mechanism was found to change from a mild fracture, consisting of multiple small plugs, to more severe fracture with fewer plugs. The most severe fracture mechanism consisted of either the powder reservoir emptying as a single plug, or of the reservoir emptying after a delay of the order of 0.1 s due to the powder sticking to its surroundings. Further to this, three different inhalation grades were compared, and the severity of the fracture was found to be inversely proportional to the flowability of the powder (measured using an annular ring shear tester). By considering the volume of aerosolised fine particles in different blends it was determined that the greater the volume of fines added to a powder, the smaller the fraction of fines that were aerosolised. This was attributed to different behaviour when fines disperse from carrier particles compared with when they disperse from agglomerates of fines. In summary, this paper demonstrates how laser diffraction can provide a more detailed analysis of an inhalation powder than just its size distribution.

Preparation and characterisation of α-alumina/ferric oxide composite abrasive

Abrasive particles are the key elements of chemical-mechanical polishing (CMP) slurry. α-alumina abrasive, commonly used in CMP slurry, often causes scratches in the polished surface because of its agglomeration and high hardness. In this paper, a kind of novel α-alumina/ferric oxide core-shell type abrasive was prepared by coating a film of ferric oxide on the surface of α-Al2O3 particles with a chemical coprecipitation method. The α-alumina/ferric oxide composite particles were characterised by time-of-flight secondary ion mass spectroscopy (TOF-SIMS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and laser particle size analyser. The results show that Fe2O3 has been successfully coated on the surface of α-alumina particles and the dispersibility of the composite particles is better than that of pure α-Al2O3 particles.

Evaluation of fuels for the synthesis of Li2CoMn3O8

Li2CoMn3O8, a 5 V cathode material used in rechargeable lithium batteries, has been synthesized by adopting a novel technique of using fuels along with the nitrate reactants. The effect of the fuel on the synthesis of Li2CoMn3O8 has been analyzed in terms of the physical and electrochemical properties of the final product formed by various methods such as solid-state carbonate fusion and the solution route using acetate and nitrate precursors. Powder X-ray diffraction FT IR spectrum, particle size, surface area and SEM analysis were carried out. The combustion method, also known as selfpropagating high temperature (SPHT) method, has been employed in the present study by using nitrate mixtures of the respective salts and a nitrogeneous fuel (urea or glycine) at a temperature of 300 °C for 3 hrs. The nitrate reactants without the addition of fuel gave only a deliquescent product even at elevated temperature (600 °C) thus indicating the necessity of fuels. Similar attempts using acetate reactants with and without the addition of nitrogeneous fuels were made separately in order to find out the necessity of fuel also in this case. The characterization of the product in terms of purity, single-phase formation and surface morphology suggested that the fuel played no role in the case of the acetate precursors. A comparative study was made on the products obtained by the acetate precursor, combustion method and the conventional carbonate method. Among the three methods, the combustion method with glycine as fuel yielded the spinel phase with high purity Li2CoMn3O8 with superior electrochemical behavior both in terms of high cell voltage and good cycle life behavior.

Hydrothermal synthesis and morphology control of boehmite

The effect of synthesis conditions on the size and morphology of boehmite particles in the sol produced by hydrothermal processing has been investigated. Transmission electron microscopy, X-ray diffraction and Laser particle size analysis were used to characterise the synthesized boehmite. Results show that the initial hydrothermal solution pH has a significant effect on the particle size and morphology. As the pH changes from low (acid) to high (alkaline), the morphology changes from a “needle-like” one to a “platelet” one. Under the conditions investigated here, the synthesis temperature and time in comparison have little apparent effect on the particle size. However, the precursor concentration, while having little noticeable effect on the elementary particle size, does result in extensive agglomeration when it is very high.