scholarly journals Direct Synthesis of (K0.5Na0.5)NbO3Powders by Mechanochemical Method

2013 ◽  
Vol 2013 ◽  
pp. 1-4 ◽  
Author(s):  
Nguyen Duc Van
Keyword(s):  
Milling Time ◽  
Direct Synthesis ◽  
Weight Ratio ◽  
Intermediate Species ◽  
X Ray Diffraction ◽  
Mechanochemical Method ◽  
X Ray ◽  
Milling Parameters ◽  
First Time ◽  
Carbonato Complex

The synthesis and structural properties of lead-free piezoelectric (K0.5Na0.5)NbO3powders prepared by mechanochemical method using Nb2O5, K2CO3, and Na2CO3as starting materials were reported. X-ray diffraction, infrared spectroscopy, Raman spectroscopy, and scanning electron microscopy were used to characterize the prepared samples. Results showed that, for the first time, by selecting the milling speed of 600 rpm and the ball-to-powder weight ratio of 35 : 1 as milling parameters, pure (K0.5Na0.5)NbO3crystalline phase was obtained directly in the as-milled samples after 5 h of milling time. The existence of a carbonato complex betweenCO32−and Nb5+ions as an intermediate species of the formation of (K0.5Na0.5)NbO3was also found.

scholarly journals Mechanochemical Preparation of Slow Release Fertilizer Based on Glauconite–Urea Complexes

Minerals ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 507 ◽  
Author(s):  
Maxim Rudmin ◽  
Elshan Abdullayev ◽  
Alexey Ruban ◽  
Ales Buyakov ◽  
Bulat Soktoev
Keyword(s):  
Milling Time ◽  
Slow Release ◽  
Mechanochemical Activation ◽  
Structural Characteristics ◽  
Fluorescence Analysis ◽  
Planetary Mill ◽  
X Ray Diffraction ◽  
Mechanochemical Method ◽  
X Ray ◽  
Slow Release Fertilizers

We investigated the mechanochemical synthesis of complex slow release fertilizers (SRF) derived from glauconite. We studied the effectiveness of the mechanical intercalation of urea into glauconite using planetary and ring mills. The potassium-nitric complex SRFs were synthesized via a mechanochemical method mixing glauconite with urea in a 3:1 ratio. The obtained composites were analyzed using X-ray diffraction analysis, scanning electron microscopy, X-ray fluorescence analysis, and infrared spectroscopy. The results show that as duration of mechanochemical activation increases, the mineralogical, chemical, and structural characteristics of composites change. Essential modifications associated with a decrease in absorbed urea and the formation of microcrystallites were observed when the planetary milling time increased from 5 to 10 min and the ring milling from 15 to 30 min. Complete intercalation of urea into glauconite was achieved by 20 min grinding in a planetary mill or 60 min in a ring mill. Urea intercalation in glauconite occurs much faster when using a planetary mill compared to a ring mill.

Optimization of High Energy Ball Milling Parameters for Synthesis of Ti1-xAlxN Powder

2016 ◽  
Vol 38 ◽  
pp. 107-113
Author(s):  
Maya Radune ◽  
Michael Zinigrad ◽  
Nachum Frage
Keyword(s):  
Milling Time ◽  
Weight Ratio ◽  
High Energy ◽  
Optimal Conditions ◽  
X Ray Diffraction ◽  
Powder Synthesis ◽  
X Ray ◽  
Orthogonal Experiments ◽  
Energy Ball ◽  
N Powder

Taguchi’s method was applied to investigate the effect of the main HEBM parameters: milling time (MT), ball to powder weight ratio (BPWR) and milling speed (MS) on the dissolved AlN fraction in TiN. The settings of HEBM parameters were determined by using the orthogonal experiments array (OA). The as-received and milled powders were characterized by X-ray diffraction (XRD). The optimum milling parameter combination was determined by using the analysis of signal-to-noise (S/N) ratio. According to the analysis of variance (ANOVA) the milling speed is the most effective parameter and the optimal conditions for powder synthesis are: MT 20h, MS 600rpm, BPWR 50:1. The result of the experiment conducted under optimal conditions (AlN was completely dissolved during experiment) confirmed the conclusions of the statistical analysis.

The Influence of Milling Time and Impact Force on the Mutual Diffusion of Al and Cu during Synthesis of Al-4.5wt%Cu Alloy via Mechanical Alloying

2009 ◽  
Vol 283-286 ◽  
pp. 494-498 ◽  
Author(s):  
Ali Mostaed ◽  
Ehsan Mostaed ◽  
Ali Shokuhfar ◽  
H. Saghafian ◽  
Hamid Reza Rezaie
Keyword(s):  
Mechanical Alloying ◽  
Milling Time ◽  
Diffusion Rate ◽  
Impact Force ◽  
Weight Ratio ◽  
Lattice Parameter ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cu Alloy ◽  
Elemental Diffusion

The study of mechanical alloying (MA) process on the immiscible Al–Cu systems having positive heats of mixing has been investigated by the earlier researchers. However, a comprehensive understanding of the diffusion phenomenon during the mechanical alloying process is still far from complete. The effects of milling time and impact force, defined as the ball-to-powder weight ratio (BPR), on the elemental diffusion during mechanical alloying process of Al-4.5wt%Cu were evaluated in the current work. X-ray diffraction results showed that increasing the milling time and impact force led to increasing the dislocation as because of increasing the micro-strain, lattice parameter and decreasing the crystallite size. As a result of this, the diffusion rate was enhanced. The interpretation of data resulted have been discussed in details.

Effects of Milling Time and Speed on Nutrient Availability of KH2PO4 with Kaolinite as Physical Type Slow/Controlled Release Fertilizers

2020 ◽  
Vol 15 (2) ◽  
pp. 51-59
Keyword(s):  
Milling Time ◽  
Slow Release ◽  
Weight Ratio ◽  
Clay Material ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Slow Release Fertilizers ◽  
Physical Type ◽  
Controlled Release Fertilizers

Mechanochemical processing was applied to produce slow-release fertilizers consisting of kaolinite as clay material and (KDP) KH2PO4 in 3:1 weight ratio by grinding the contents in a planetary ball mill at milling rotational speeds ranging from 200 to 700 rpm for 2 h and at different milling times ranging between 1-3 h at 600 rpm milling speed. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermal gravimetric analysis (TGA) and coupled ion chromatography (IC) were used to characterize the prepared samples. It was shown that the mechanochemical process succeeded to incorporate KDP into the kaolinite structure. The K+ and PO43- ions released from the kaolinite–KH2PO4 system when dispersed in distilled water for 24 h were measured. The results indicate that the prepared kaolinite–KH2PO4 system acts as a carrier of K+ and PO43- nutrients to be used as slow-released fertilizers

Preparation of TiO2-diatomite composites by ball-milling and its photocatalytic degradation of methyl orange

2011 ◽  
Vol 11 (1) ◽  
pp. 121-127 ◽  
Author(s):  
Yanxi Deng ◽  
Xuming Wang ◽  
Jinfeng Yin ◽  
Yanfeng Li ◽  
Hao Ding ◽  
...  
Keyword(s):  
Methyl Orange ◽  
Photocatalytic Degradation ◽  
Ball Milling ◽  
Particle Concentration ◽  
Milling Time ◽  
Weight Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ball Milling Technique ◽  
Degradation Of Methyl Orange

TiO2-diatomite composites were prepared using a two–stage ball-milling technique and they were subsequently characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and FTIR, showing that nanotitania had been successfully supported on the surface of diatomite. The as-prepared TiO2–diatomite composites were used to decompose methyl orange (MO). Good degradation efficiency was observed. The effects of milling conditions, such as milling time of diatomite suspension, the diatomite particle concentration in suspension, weight ratio of ball-to-powder, milling time of the mixed TiO2-diatomite suspension and dosage of titania, on photocatalytic degradation performance were systematically examined for the sake of achieving the best efficiency.

Effect of Milling Parameters on the TiB and TiB2 Formation in Ti-50at%B and Ti-66at%B Powders

2008 ◽  
Vol 591-593 ◽  
pp. 135-140 ◽  
Author(s):  
Gilbert Silva ◽  
Erika Coaglia Trindade Ramos ◽  
Alfeu Saraiva Ramos
Keyword(s):  
Energy Condition ◽  
Weight Ratio ◽  
Dsc Analysis ◽  
X Ray Diffraction ◽  
Mechanically Alloyed ◽  
Powder Mixtures ◽  
X Ray ◽  
Milling Parameters ◽  
Equilibrium Structures ◽  
Rotary Speed

This work discusses on the effect of milling parameters on the TiB and TiB2 formation in Ti-50at%B and Ti-66at%B powders, respectively. Both powder mixtures were processed in a planetary ball Fritsch P-5 ball mill under Ar atmosphere, varying the milling parameters: rotary speed (150 and 200 rpm), size of balls (10 and 19mm diameter) and ball-to-powder weight ratio (2:1 and 10:1). In order to obtain the equilibrium structures the milled powders were heated at 1200oC for 1h. Samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermal analysis (DSC). XRD results indicated that extended Ti(B) solid solutions were formed during ball milling of Ti-50at%B and Ti-66at%B powders. After milling for 170h it was noted the TiB and TiB2 formation in Ti-50B and Ti-66B powders processed under higher-energy condition. DSC analysis revealed that the TiB2 formation was completed during heating of mechanically alloyed Ti-66at%B powders only. After heating at 1200oC for 1h, a large amount of TiB and TiB2 was found in Ti-B powders milled under higher energy condition.

The Research of Influence on Fe-N Alloy Magnetism from Experiment Parameters

2013 ◽  
Vol 690-693 ◽  
pp. 470-474
Author(s):  
Xiu Zhi Guo ◽  
Ruo Hui Chen ◽  
Wen Fu Song
Keyword(s):  
Phase Transition ◽  
Ball Milling ◽  
Milling Time ◽  
Hexagonal Boron Nitride ◽  
Weight Ratio ◽  
Alloy Formation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transition Rules ◽  
Similar Phase

Fe-N amorphous alloy and ε- FexN alloy were prepared by mechanical ball milling with Fe and solid hexagonal boron nitride (h-BN) as nitrogen resource. The microstructural and magnetic transforming rules of different volume ratios of mixtures of Fe and h-BN (1:12.5, 1:5.4, 1:1.2, and 1:0.38) was studied under different ball-to-powder weight ratios. phase transition and magnetism were characterized with X-ray diffraction and vibrating sample magnetometer (VSM). According to the results, samples of the first three volume ratios have similar phase transition rules in different ball-to-powder weight ratios, and the sample with smaller ball-to-powder weight ratio costs more time in alloy formation. The changing rules and mechanisms of coercivity of four ratio samples with the extension of ball milling time has been clarified.

Effect of Milling Parameters on Morphology and Grain Size of WO3 and Al Particles for Fabricating WO3/Al Composites

2010 ◽  
Vol 638-642 ◽  
pp. 939-943
Author(s):  
Q.W. Wang ◽  
Y.C. Feng ◽  
Guo Hua Fan ◽  
Gui Song Wang ◽  
Lin Geng
Keyword(s):  
Particle Size ◽  
Grain Size ◽  
Milling Time ◽  
Marked Change ◽  
Weight Ratio ◽  
Milling Process ◽  
X Ray Diffraction ◽  
Aluminum Particles ◽  
Milling Parameters ◽  
Electronic Microscope

In this paper, the milling process of WO3 and aluminum particles is studied. Influences of rotate rate, milling time and ball-to-powder weight ratio on the morphology and grain size of the particles are studied by scanning electronic microscope and X-ray diffraction techniques. Al particle size decreases firstly and then increases with increasing milling time, while Al grain size decreases gradually as the milling time increases. WO3 particle is distributed uniformly in Al particles after milling for 9h, and has no marked change as further extension of milling time. With increasing the ball-to-powder weight ratio and rotate rate, both particle size and grain size of Al decreases. milling parameters have almost no effect on the grain size of the WO3 particles.

Mechanical properties of FeAlSi powders prepared by mechanical alloying from different initial feedstock materials

2019 ◽  
Vol 107 (2) ◽  
pp. 207 ◽  
Author(s):  
Jaroslav Čech ◽  
Petr Haušild ◽  
Miroslav Karlík ◽  
Veronika Kadlecová ◽  
Jiří Čapek ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Mechanical Alloying ◽  
Young’S Modulus ◽  
Milling Time ◽  
Young's Modulus ◽  
Element Model ◽  
X Ray Diffraction ◽  
X Ray ◽  
Powder Particles ◽  
Complete Homogenization

FeAl20Si20 (wt.%) powders prepared by mechanical alloying from different initial feedstock materials (Fe, Al, Si, FeAl27) were investigated in this study. Scanning electron microscopy, X-ray diffraction and nanoindentation techniques were used to analyze microstructure, phase composition and mechanical properties (hardness and Young’s modulus). Finite element model was developed to account for the decrease in measured values of mechanical properties of powder particles with increasing penetration depth caused by surrounding soft resin used for embedding powder particles. Progressive homogenization of the powders’ microstructure and an increase of hardness and Young’s modulus with milling time were observed and the time for complete homogenization was estimated.

scholarly journals Quartz Crystallite Size and Moganite Content as Indicators of the Mineralogical Maturity of the Carboniferous Chert: The Case of Cherts from Eastern Asturias (Spain)

Minerals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 611
Author(s):  
Celia Marcos ◽  
María de Uribe-Zorita ◽  
Pedro Álvarez-Lloret ◽  
Alaa Adawy ◽  
Patricia Fernández ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Crystallite Size ◽  
Archaeological Sites ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Infrared And Raman Spectroscopy ◽  
First Time ◽  
Geological Formations

Chert samples from different coastal and inland outcrops in the Eastern Asturias (Spain) were mineralogically investigated for the first time for archaeological purposes. X-ray diffraction, X-ray fluorescence, transmission electron microscopy, infrared and Raman spectroscopy and total organic carbon techniques were used. The low content of moganite, since its detection by X-ray diffraction is practically imperceptible, and the crystallite size (over 1000 Å) of the quartz in these cherts would be indicative of its maturity and could potentially be used for dating chert-tools recovered from archaeological sites. Also, this information can constitute essential data to differentiate the cherts and compare them with those used in archaeological tools. However, neither composition nor crystallite size would allow distinguishing between coastal and inland chert outcrops belonging to the same geological formations.

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