High Energy Milling of Alumina Synthesized by Combustion Reaction Using a Vertical Shaft Attritor Mill: Influence of the Milling Time Length

2015 ◽  
Vol 820 ◽  
pp. 155-160 ◽  
Author(s):  
Mirele Costa da Silva ◽  
N.C.O. Costa ◽  
D.S. Lira ◽  
Joelda Dantas ◽  
A.C.F.M. Costa ◽  
...  
Keyword(s):  
Milling Time ◽  
Particle Diameter ◽  
High Energy ◽  
Particle Size Analysis ◽  
Combustion Reaction ◽  
Size Analysis ◽  
Average Particle ◽  
Length Variation ◽  
Average Particle Diameter ◽  
Time Length

Among the vast applications in which the α-alumina can apply, the literature has reported researches which aim to achieve better features of these materials varying the obtainment methodology and some post-obtainment techniques. Thus, this paper aims to evaluate how different milling time lengths of 15, 30, 45 and 60 minutes alter the structure and morphology of α-alumina powders synthesized by combustion reaction. The time and temperature of the combustion reaction were evaluated during the synthesis of the alumina. The samples of non-milled and milled alumina were characterized by XRD and particle size analysis. The results showed that the maximum achieved temperature of reaction was 598°C. The milling time length variation did not alter the stable α-Al2O3majority crystal phase present in all samples. The average particle diameter was reduced from 23.3 to 10.5 μm comparing the non-milled and the sample milled for 60s.

Effect of SiC Nanoparticles Content and Milling Time on the Characteristics of Al/SiC Nanocomposite Powders Produced via Mechanical Milling

2013 ◽  
Vol 829 ◽  
pp. 505-509 ◽  
Author(s):  
Farshad Akhlaghi ◽  
Sareh Mosleh-Shirazi
Keyword(s):  
Crystal Size ◽  
Milling Time ◽  
Matrix Alloy ◽  
High Energy ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Sic Nanoparticles ◽  
Sic Particles ◽  
The Matrix ◽  
Nanocomposite Powders

In the present study high energy ball milling was utilized to produce aluminum (Al-6061) matrix nanocomposite powders reinforced with nanosilicon carbide (SiC) particles. The starting materials containing different percentages (1,3 or 5 wt.%) of nanoSiC particles (25-50 nm) and Al (38-63 μm) were co-milled for different times (16, 20, 24 h) to achieve nanocomposite powders. The crystal size of powders were evaluated by quantitative XRD analysis. Laser particle size analysis was used to evaluate the size of powders during milling. The microstructure of powders and their microhardness values were evaluated by Scanning Electron Microscopy (SEM) and a microhardness tester respectively. The results indicated that the crystal size of the matrix alloy decreased by milling time. The increased SiC content up to 3% resulted in increased microhardness of the powders. However, further increase of SiC to 5% resulted in decreased microhardness due to agglomeration. It was concluded that the maximum microhardness together with a uniform distribution of SiC particles within the matrix alloy was obtained after 20 h milling of powder mixture containing 3% of SiC nanoparticles.

scholarly journals Effects of milling temperature and time on phase evolution of Ti-based alloy

2021 ◽  
pp. 55-55
Author(s):  
F. Kristaly ◽  
M. Sveda ◽  
A. Sycheva ◽  
T. Miko ◽  
A. Racz ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Milling Time ◽  
Nanocrystalline Structure ◽  
Phase Evolution ◽  
High Energy ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Scanning Calorimetry ◽  
Cell Parameters ◽  
Milling Temperature

Ti50Cu25Ni20Sn5 (at.%) powder was subjected to high-energy ball milling at room temperature and -78?C. As a function of the milling time, evaluation of phases, morphology and the refinement of grain size were investigated by scanning electron microscopy (SEM) and X-ray diffraction analysis (XRD), differential scanning calorimetry (DSC), transmission electron microscopy (TEM), and laser-diffraction particle size analysis (PSA). The transformation of the crystalline structure into an amorphous structure and then the transformation into a nanocrystalline structure during further milling was detected. The stress-induced martensitic transformation has taken place after 30 min milling time at both temperatures, the cubic Cu(Ni,Cu)Ti2 phase transforms into the orthogonal structure. The hardness value of powders after 150 min milling time increases from 506 to 780 HV0.01. The milling temperature does not significantly influence the amount of amorphous fraction (33-36 wt.%) but the composition of amorphous content is more influenced by temperature. The interval of crystallite size was between 1.2 and 11.7 nm after 180 min of milling. The amount and the cell parameters of the Sn-containing phases are different between the two milling experiments, owing to the diffusion coefficients of the Sn atom differ to a large extent.

Development of Ni/h-BN Self-Lubricating Composite Powder by High-Energy Ball Milling

2016 ◽  
Vol 869 ◽  
pp. 277-282
Author(s):  
Moisés Luiz Parucker ◽  
César Edil da Costa ◽  
Viviane Lilian Soethe
Keyword(s):  
Ball Milling ◽  
Milling Time ◽  
Solid Lubricants ◽  
High Energy ◽  
High Energy Ball Milling ◽  
Second Phase ◽  
Average Particle ◽  
Composite Powders ◽  
The Matrix ◽  
Energy Ball

Solid lubricants have had good acceptance when used in problem areas where the conventional lubricants cannot be applied: under extreme temperatures, high charges and in chemically reactive environments. In case of materials manufactured by powder metallurgy, particles of solid lubricants powders can be easily incorporated to the matrix volume at the mixing stage. In operation, this kind of material provides a thin layer of lubricant that prevents direct contact between the surfaces. The present study aimed at incorporating particles of second phase lubricant (h-BN) into a matrix of nickel by high-energy ball milling in order to obtain a self-lubricating composite with homogeneous phase distribution of lubricant in the matrix. Mixtures with 10 vol.% of h-BN varying the milling time of 5, 10, 15 and 20 hours and their relationship ball/powder of 20:1 were performed. The effect of milling time on the morphology and microstructure of the powders was studied by X-ray diffraction, SEM and EDS. The composite powders showed reduction in average particle size with increasing milling time and the milling higher than 5 hours resulted in equiaxial particles and the formation of nickel boride.

Preparation and pharmacokinetics of cefquinome sulfate liposomes in goats

2018 ◽  
Author(s):  
Haigang Wu ◽  
Jinni Liu ◽  
Gugangke Xu ◽  
Zhaowei Ye ◽  
Jicheng Liu and Benchi Yi
Keyword(s):  
Plasma Concentration ◽  
Particle Diameter ◽  
Entrapment Efficiency ◽  
Maximum Plasma Concentration ◽  
Maximum Plasma ◽  
Average Particle ◽  
Average Particle Diameter ◽  
Ethanol Injection ◽  
Elimination Half ◽  
Time Point

We evaluated the pharmacokinetics of cefquinome sulfate (CEF) liposomes in eight healthy goats following intramuscular administration at 4 mg/kg. The average particle diameter of CEF liposomes prepared by the ethanol injection method was 335nm with a CEF entrapment efficiency of 69.56%. The elimination half-life (t1/2b) of CEF liposomes was 33.04h compared with 16.21 h for CEF injected without carrier (p less than 0.05). The area under the concentration curve (AUC) for CEF liposomes was approximately three-times greater than for CEF alone (P less than 0.05). The time-point of maximum plasma concentration of the drug (Tp) and the maximum plasma concentration (Cmax) were 4.38 h and 1.99 ìg/mL for CEF liposomes, compared with 1.86 h and 3.55 ìg/mL for CEF without carrier, respectively. 

scholarly journals Morphology and Degradation of Multicompartment Microparticles Based on Semi-Crystalline Polystyrene-block-Polybutadiene-block-Poly(L-lactide) Triblock Terpolymers

Polymers ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 4358
Author(s):  
Nicole Janoszka ◽  
Suna Azhdari ◽  
Christian Hils ◽  
Deniz Coban ◽  
Holger Schmalz ◽  
...  
Keyword(s):  
Cross Sections ◽  
Ring Opening ◽  
Particle Diameter ◽  
Average Particle ◽  
Average Particle Diameter ◽  
Selective Degradation ◽  
The Core ◽  
Transmission Electron ◽  
And Control ◽  
Triblock Terpolymers

The confinement assembly of block copolymers shows great potential regarding the formation of functional microparticles with compartmentalized structure. Although a large variety of block chemistries have already been used, less is known about microdomain degradation, which could lead to mesoporous microparticles with particularly complex morphologies for ABC triblock terpolymers. Here, we report on the formation of triblock terpolymer-based, multicompartment microparticles (MMs) and the selective degradation of domains into mesoporous microparticles. A series of polystyrene-block-polybutadiene-block-poly(L-lactide) (PS-b-PB-b-PLLA, SBL) triblock terpolymers was synthesized by a combination of anionic vinyl and ring-opening polymerization, which were transformed into microparticles through evaporation-induced confinement assembly. Despite different block compositions and the presence of a crystallizable PLLA block, we mainly identified hexagonally packed cylinders with a PLLA core and PB shell embedded in a PS matrix. Emulsions were prepared with Shirasu Porous Glass (SPG) membranes leading to a narrow size distribution of the microparticles and control of the average particle diameter, d ≈ 0.4 µm–1.8 µm. The core–shell cylinders lie parallel to the surface for particle diameters d < 0.5 µm and progressively more perpendicular for larger particles d > 0.8 µm as verified with scanning and transmission electron microscopy and particle cross-sections. Finally, the selective degradation of the PLLA cylinders under basic conditions resulted in mesoporous microparticles with a pronounced surface roughness.

scholarly journals Assessment of Physical, Microstructural, Thermal, Techno-Functional, And Rheological Characteristics of Apple (Malus Domestica) Seeds of Northern Himalayas

2021 ◽  
Author(s):  
Mehnaza Manzoor ◽  
Jagmohan Singh
Keyword(s):  
Energy Requirement ◽  
Geometric Mean ◽  
High Energy ◽  
Particle Size Analysis ◽  
Absorption Capacity ◽  
Size Analysis ◽  
Scanning Electron Micrographs ◽  
Seed Flour ◽  
Mean Diameter ◽  
Golden Delicious

Abstract The study examined the physical, morphological, thermal, techno-functional, and rheological properties of two apple seed cultivars viz: red delicious (RD) and golden delicious (GD). Physical properties showed that red delicious seeds were significantly (p≤0.05) different in width, geometric mean diameter, arithmetic mean diameter, volume, and surface area than golden delicious seeds. The proximate composition of RD seed flour showed a higher amount of crude protein and fat content than GD seed flour. RD seed flour was significantly different in L*, a*, b* values, bulk density, water/oil absorption capacity and the emulsifying ability than GD seed flour. From particle size analysis it was possible to found that GD was significantly (p≤0.05) lower than RD flour macromolecules. Scanning electron micrographs showed oval/spherical starch granules of small size embedded in a continuous protein matrix. Thermograph revealed exothermic transition enthalpy for both RD and GD seed flour, which indicates a high energy requirement for crystallite melting. The rheological assays revealed high elastic modulus (G′), of seed flours that will help in modifying the texture of foods. This study suggests the potential of apple seeds in the formulation of protein-enriched foods to combat malnutrition while contributing to the reduction in industrial wastage.

Research on the Efficient Application of Silica Fume in High-Tech Cement-Based Materials

2011 ◽  
Vol 374-377 ◽  
pp. 1537-1540
Author(s):  
Dong Lin ◽  
Zi Yun Wen
Keyword(s):  
Compressive Strength ◽  
Silica Fume ◽  
Packing Density ◽  
Particle Diameter ◽  
High Tech ◽  
Average Particle ◽  
Average Particle Diameter ◽  
Cement Based Materials ◽  
Pre Treatment

The comparison experiments are carried out at different silica fume dosage between the silica fume with pre-treatment and the silica fume without pre-treatment. The results show that the pre-treatment of silica fume improved the strength greatly and the silica fume dosage corresponding to the strength peak somewhat moved forward from 0.20 for the cement-based materials with pre-treatment of silica fume to 0.21 for the cement-based materials without pre-treatment of silica fume. The particles distribution experiment results indicate that after the pre-treatment of silica fume, the average particle diameter of silica fume reduced from 2.865μｍto 0.151μｍ. Based on Aim-Goff model, it is concluded that the increase in the compressive strength and flextural strength of cement-based materials with pre-treatment of silica fume, are attributed to the dispersion of silica fume agglomeration and the increase in the packing density of the cement-based materials.

scholarly journals Effect of Nanosized Colloidal Copper on Cotton Fabric

2010 ◽  
Vol 5 (3) ◽  
pp. 155892501000500 ◽  
Author(s):  
D.P. Chattopadhyay ◽  
B.H. Patel
Keyword(s):  
Particle Size ◽  
Cotton Fabric ◽  
Colloidal Solution ◽  
Chemical Reduction ◽  
Average Particle Size ◽  
Particle Size Analysis ◽  
Nano Particles ◽  
Size Analysis ◽  
Average Particle ◽  
Sem Images

This research deals with the synthesis of nanosized copper as colloidal solution and its application to cotton fabric. Copper nano colloids were prepared by chemical reduction of copper salt using sodium borohydride as reducing agent in presence of tri-sodium citrate. The size and size distribution of the particles were examined by particle size analyzer and the morphology of the synthesized particles was examined by SEM and AFM techniques. X-ray fluorescence spectroscopy detected the presence of copper in the treated fabric. The results of particle size analysis showed that the average particle size varied from 60 nm to 100 nm. The nano copper treated cotton was subjected to soil burial test for the assessment of its resistance towards microbial attack. SEM images of treated fabric indicate copper nano particles are well dispersed on the surface of the specimens. The treatments of nano copper colloidal solution on cotton not only improve its antimicrobial efficiency but also influenced the tensile strength of the fabric sample positively. The treatment was found to enhance the color depth and fastness properties of direct dyed cotton fabric samples.

Effect of Bi Ions on the Hyperthermia Properties of Hyaluronic Acid-Coated La1−xSrxMnO3 Nanoparticles

NANO ◽  
2020 ◽  
Vol 15 (01) ◽  
pp. 2050015
Author(s):  
Lihan zheng ◽  
Yuanwei Chen ◽  
Ying Wang ◽  
Peng Wang ◽  
Tao Wang
Keyword(s):  
Hyaluronic Acid ◽  
Magnetic Nanoparticles ◽  
Curie Temperature ◽  
Absorption Rate ◽  
Specific Absorption Rate ◽  
Heating Temperature ◽  
Particle Diameter ◽  
High Energy ◽  
Average Particle ◽  
Specific Absorption

Self-regulating temperature hyperthermia based on magnetic fluid with low Curie temperature is a moderately effective method for cancer treatment. The improvement of the properties of magnetic fluids is the key for application of this method. In this paper, Bi-doped LSMO magnetic nanoparticles were synthesized using a simple sol–gel method and coated by hyaluronic acid through high energy ball milling for their possible application in self-regulating temperature hyperthermia. The crystal structure, morphology, basic magnetic properties and heating properties of these nanoparticles in a high frequency magnetic field were investigated. It was found that the hyaluronic acid-coated La[Formula: see text]Sr[Formula: see text]Bi[Formula: see text]MnO3 magnetic nanoparticles, with an average particle diameter of [Formula: see text]100[Formula: see text]nm and a Curie temperature of 48∘C, possess outstanding induction heating properties. The saturation heating temperature, specific absorption rate and effective specific absorption rate are 48∘C, 117[Formula: see text]W/g and 0.27[Formula: see text]W/g[Formula: see text]kHz[Formula: see text](kA/m2), respectively.

A Novel Method for Mixing Nanomaterials with Soil

2019 ◽  
Vol 25 ◽  
pp. 46-68 ◽  
Author(s):  
Ali Akbar Firoozi ◽  
Mohd Raihan Taha ◽  
Tanveer Ahmed Khan ◽  
Farzad Hejazi ◽  
Ali Asghar Firoozi ◽  
...  
Keyword(s):  
Copper Oxide ◽  
Ball Milling ◽  
Milling Time ◽  
Mixing Time ◽  
Weight Ratio ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Concentration Data ◽  
X Ray ◽  
Electron Microscopy Analysis

Mixing of nano-sized powders with soils (macro-sized powders) is a noteworthy issue for geotechnical projects. Thus, this study examined the horizontal ball mill mixing of nano-copper oxide with kaolinite. Ball milling parameters (rotation speed, weight ratio of balls to powder and milling time) of the planetary ball milling were optimized for proper mixing of nano-copper oxide and kaolinite powder. Results showed that increase in mixing time decreased the agglomeration of nano-copper powders and kaolinite and increased the homogeneity of nano-copper powder with kaolinite particles. The quality of mixing was assessed through intensity and scale of segregation using concentration data obtained through energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) analyses. It was observed through these two tests that, increase in ball milling time after 6 hours resulted in grain size reduction. Field emission scanning electron microscopy analysis showed that nano-coppers were regularly found on the surface of kaolinite particles after 6 hrs. of horizontal milling at 4:1 ratio of balls to powder mixture. Furthermore, 24 hrs. mixing resulted in grinding of kaolinite particles and hence their size was reduced. Particle size analysis confirmed these results, as the highest size span value of 3.417 was observed after 6 hrs. milling with speed of 200 rpm.

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