scholarly journals ВПЛИВ МЕХАНІЧНОЇ АКТИВАЦІЇ НА РОЗМІРНІ ХАРАКТЕРИСТИКИ ТА ФОРМУ ЧАСТИНОК ГЛИНОПОРОШКІВ РІЗНОГО ТИПУ

2022 ◽  
pp. 60-68
Author(s):  
YURII BUDASH ◽  
NATALIA TARASENKO ◽  
VIKTORIIA PLAVAN ◽  
MYKOLA ZATOLOKIN ◽  
TATIANA SHYLINTSEVA
Keyword(s):  
Mechanical Activation ◽  
Morphometric Analysis ◽  
Particle Diameter ◽  
Shape Index ◽  
Mechanical Action ◽  
Statistical Characteristics ◽  
Equivalent Diameter ◽  
Activation Process ◽  
Imagej Software ◽  
Shape Of Particles

Purpose. Determination of the influence of the process of preliminary mechanical activation on the dimensional characteristics and shape of particles of different types of clay powders.Methodology. Clay powders of montmorillonite and palygorskite type were chosen as the objects of research in this work. The process of mechanical activation of clay powders was carried out using a laboratory ball mill. For microanalysis of sample particles, the method of optical polarizing microscopy was used. Morphometric analysis of clay powder particles was performed by image analysis using the ImageJ software. At the same time, the area and perimeter were determined, and the equivalent diameter and also the shape index of the particles of the samples were calculated. The experimental data were statistically processed using the Statistica and Excel software packages.Results. The paper investigates the effect of the process of mechanical activation on the dimensional characteristics and shape of particles of montmorillonite and palygorskite type clay powders. It was found that the decrease in the average values of the equivalent particle diameter in the process of mechanical action (~14–15%) is realized mainly due to the destruction of their largest aggregates. Moreover, the intensity of this process is noticeably higher for clay of the montmorillonite type. It is shown that for both studied samples, the process of mechanical activation leads to an increase in the average values of the particle shape index (~ by 9–10%) and an increase in the uniformity of their distribution by this index.Scientific novelty. Using a detailed morphometric analysis of particles of various types of clay powders, the regularities of the influence of the mechanical activation process on the quantitative statistical characteristics of their distribution over the equivalent diameter and shape index have been established.Practical value. The results obtained will make it possible to reasonably approach the choice of pretreatment methods for clay powders intended for the production of polymer filled nanocomposite materials.

scholarly journals Визначення розмірних характеристик частинок глинопорошків як нанонаповнювачів полімерних композицій

2020 ◽  
Vol 138 (5) ◽  
pp. 122-131
Author(s):  
Ю. О. Будаш ◽  
В. І. Ступа ◽  
М. В. Лубська ◽  
К. В. Пушкаренко ◽  
І. П. Силенок
Keyword(s):  
Morphometric Analysis ◽  
Digital Camera ◽  
Statistical Processing ◽  
Polymeric Composite ◽  
Polymer Nanocomposite ◽  
Shape Index ◽  
Nanocomposite Materials ◽  
Equivalent Diameter ◽  
Polarization Microscopy ◽  
Different Types

Comparative morphometric analysis of different types and brands of clay powders of domestic origin for the reasonable choice of filler of polymer nanocomposite materials with improved properties. Morphometric analysis of alumina particles was performed by optical polarization microscopy. Micrographs were obtained using a digital camera with an adapter. To quantify the size of clay particles, we used the image analysis method in ImageJ program. The area, perimeter were determined, and the equivalent diameter and particle shape index were calculated. Statistical processing of the experimental data was performed using the software packages "Statistica" and "Excel". A comparative morphometric analysis of various types and grades of clay powders of domestic origin, intended for use as nanofillers in the production of polymeric composite materials with improved properties, was performed. It was found that the nature of the distribution of particles of equivalent diameter in all the studied samples is qualitatively similar, but has certain differences in quantitative indicators. The distribution of particles of the studied brands of clay powders according to the shape indicator showed a pronounced asymmetry towards its maximum values. On the basis of a detailed morphometric analysis of particles of different types of clay powders, differences in the quantitative characteristics of the particle distribution by the equivalent diameter and shape index were established. The results obtained will allow a reasonable approach to the selection of the brand of clay, which will be used as filler in the production of polymeric nanocomposite materials.

scholarly journals Multistage Mechanical Activation of Multilayer Carbon Nanotubes in Creation of Electric Heaters with Self-Regulating Temperature

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4654
Author(s):  
Alexandr Viktorovich Shchegolkov ◽  
Sung-Hwan Jang ◽  
Aleksei Viktorovich Shchegolkov ◽  
Yuri Viktorovich Rodionov ◽  
Olga Anatolievna Glivenkova
Keyword(s):  
Carbon Nanotubes ◽  
Temperature Field ◽  
Mechanical Activation ◽  
Thermal Effect ◽  
Supply Voltage ◽  
Mechanical Energy ◽  
Mechanical Action ◽  
Multilayer Carbon Nanotubes ◽  
Starting Current ◽  
Paddle Mixer

The article deals with research related to the issues of nanomodification of elastomers as a basis of electric heaters with self-regulating temperature. The effect of multistage mechanical activation of multilayer carbon nanotubes (MCNTs) with graphite on the uniformity of the temperature field distribution on the surface of nanomodified organosilicon elastomer has been studied. The influence of the stages of mechanical action on the parameters of MCNTs is revealed. It has been ascertained that for the MCNTs/graphite bulk material, which has passed the stage of mechanical activation in the vortex layer apparatus, a more uniform distribution of the temperature field and an increase in temperature to 57.1 °C at the supply voltage of 100 V are typical. The distribution of the temperature field in the centrifugal paddle mixer “WF-20B” for mixing MCNTs with graphite has been investigated. It has been found that there is also a thermal effect in addition to the mechanical action on the MCNTs in the paddle mixer “WF-20B”. The thermal effect is associated with the transfer of the mechanical energy of friction of the binary mixture MCNTs/graphite on the paddle and the walls of the vessel. The multiplicity of the starting current Ip to the nominal In (Ip/In) is 5 for the first sample, 7.5 for the second sample, and 10 for the third sample at the supply voltage of 100 V. The effect of reducing the starting current and stabilizing the temperature indicates the presence of self-regulation, which is expressed in maintaining a certain level of temperature.

scholarly journals Digital microscopic image application (DMIA), an automatic method for particle size distribution analysis in waste activated sludge

2021 ◽  
Author(s):  
S. Cazares ◽  
J. A. Barrios ◽  
C. Maya ◽  
G. Velásquez ◽  
M. Pérez ◽  
...  
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Activated Sludge ◽  
Size Distribution ◽  
Particle Diameter ◽  
Diffraction Method ◽  
Laser Diffraction ◽  
Waste Activated Sludge ◽  
Equivalent Diameter ◽  
Distribution Analysis

Abstract An important physical property in environmental samples is particle size distribution. Several processes exist to measure particle diameter, including change in electrical resistance, blocking of light, the fractionation of field flow and laser diffraction (these being the most commonly used). However, their use requires expensive and complex equipment. Therefore, a Digital Microscopic Imaging Application (DMIA) method was developed adapting the algorithms used in the Helminth Egg Automatic Detector (HEAD) software coupled with a Neural Network (NN) and Bayesian algorithms. This allowed the determination of particle size distribution in samples of waste activated sludge (WAS), recirculated sludge (RCS), and pretreated sludge (PTS). The recirculation and electro-oxidation pre-treatment processes showed an effect in increasing the degree of solubilization (DS), decreasing particle size and breakage factor with ranges between 44.29%, and 31.89%. Together with a final NN calibration process, it was possible to compare results. For example, the 90th percentile of Equivalent Diameter (ED) value obtained by the DMIA with the corresponding result for the laser diffraction method. DMIA values: 228.76 μm (WAS), 111.18 μm (RCS), and 84.45 μm (PTS). DMIA processing has advantages in terms of reducing complexity, cost and time, and offers an alternative to the laser diffraction method.

Comparative kinetic study of mechanical activation process of mica and talc for industrial application

2014 ◽  
Vol 59 ◽  
pp. 181-190 ◽  
Author(s):  
Ljubiša Andrić ◽  
Anja Terzić ◽  
Zagorka Aćimović-Pavlović ◽  
Ljubica Pavlović ◽  
Milan Petrov
Keyword(s):  
Kinetic Study ◽  
Mechanical Activation ◽  
Industrial Application ◽  
Activation Process

Effect of mechanical activation on the structure of pulverized coal and iron ore powder

2019 ◽  
Vol 116 (6) ◽  
pp. 624
Author(s):  
Rufei Wei ◽  
Dongwen Xiang ◽  
Hongming Long ◽  
Jiaxin Li ◽  
Qingmin Meng
Keyword(s):  
Free Energy ◽  
Mechanical Activation ◽  
Gibbs Free Energy ◽  
Iron Ore ◽  
Pulverized Coal ◽  
Activation Process ◽  
Free Energies ◽  
Boundary Area ◽  
Particle Sizer ◽  
Storage Energy

Morphologies and structures of pulverized coal and iron ore powder after mechanical activation were studied by SEM, XRD, FTIR and laser particle sizer. The microcrystalline structure of coal was found to be destroyed by mechanical activation via reducing the pile height and number of layers, and the organic structure of coal was altered through the destruction of the ether bond. Mechanical activation led to distortions and dislocations of the crystal lattice of iron ore, decreasing crystallite size, increasing the grain boundary area, and producing an amorphous phase. These increased the Gibbs free energies of dislocations and grain boundaries as well as the surface Gibbs free energy and the amorphization Gibbs free energy, which would eventually increase the energy stored in iron ore called mechanical storage energy. The longer the mechanical activation process, the higher mechanical storage energy for the iron ore will be saved. The amorphization Gibbs free energy is the biggest among the four kinds of Gibbs free energy, accounting for 94.8% ∼ 87.1% of the total storage energy in the mechanical activated iron ore.

Influence of Particle Size Distribution, Energy Condition and Reactivity of the Deposited Material on Nanopatterning of Surface Layers Made of Shape Memory Materials

2017 ◽  
Vol 730 ◽  
pp. 8-14 ◽  
Author(s):  
Zhesfina Michailovna Blednova ◽  
Peter Olegovich Rusinov ◽  
Maria Evgenievna Bezmogorychnaya
Keyword(s):  
Shape Memory ◽  
Mechanical Activation ◽  
Energy Intensity ◽  
Energy Condition ◽  
Thermodynamic Characteristics ◽  
Basic Material ◽  
Activation Process ◽  
Surface Layers ◽  
Study Results ◽  
Shape Memory Materials

The article contains a block diagram of the mechanical activation process of multicomponent shape memory materials, taking into account the variety of influencing factors. We proposed to evaluate the reactivity of the deposited material by using the energy criterion (energy intensity), determined by additivity concept as an amount of the basic material energy and energy accumulated during mechanical activation. The energy intensity of the basic material depends on the chemical and phase composition and is determined by the thermodynamic characteristics and is based on diagrams of the systems. The energy accumulated during the MA, is determined on the basis of X-ray structural analysis. We have shown experimentally that increase in fineness of grind leads to growth in the number of active centers. This enables nanopatterning of surface layers in high-velocity oxygen-fuel spraying (HVOF). Increasing the time of MA (1.5 h) promotes a more homogeneous structure during HVOF. The study results allow developing practical recommendations for effective implementation of multi-component SME materials with HVOF.

Preparation of Nano Ti3SiC2/MoSi2 Composite by SPS Process

2011 ◽  
Vol 284-286 ◽  
pp. 2414-2419 ◽  
Author(s):  
Jun Cai Zhang ◽  
Cheng Chang Jia
Keyword(s):  
Mechanical Activation ◽  
Particle Diameter ◽  
Second Phase ◽  
Strong Restriction ◽  
Matrix Surface ◽  
Second Phase Particles ◽  
The Matrix ◽  
Strong Repulsion

In this paper, nano-Ti3SiC2/MoSi2 composite, whose second phase was 20-150nm, was in situ prepared by mechanical activation (MA) and SPS process with the quaternary powers of Mo, Si, Ti, and C. The results showed that: (1) matrix MoSi2 has strong repulsion to other elements, which leads to more second-phase particles inside the matrix rather than on the matrix surface; (2) matrix MoSi2 has strong restriction on the growing of the second phase, which makes the particle diameter of the second phase inside the matrix only in 200 nm around, while that over the surface reaches to 800 nm around.

Formation of Rod-Like Al2TiO5 Via Mechanical Activation Followed by Thermal Processing

2007 ◽  
Vol 534-536 ◽  
pp. 53-56 ◽  
Author(s):  
Xiao Hu Chen ◽  
Xiao Min Chen ◽  
Huang Zhao ◽  
Ji Huai Wu
Keyword(s):  
Mechanical Activation ◽  
Thermal Processing ◽  
Room Temperature ◽  
Milled Powder ◽  
Planetary Mill ◽  
Activation Process ◽  
Powder Mixtures ◽  
Positive Effects ◽  
Typical Morphology

The purpose of this paper is to investigate the possibility of rod-like Al2TiO5 formation via a mechanical activation process. A QM-ISP-4 Planetary Mill was employed to activate mechanically the mixtures of anatase and corundum in air at room temperature for different times. The milled powder mixtures were then sintered in air at 1300°C for 1 h. The XRD results showed that the milled powder mixtures were completely transformed into Al2TiO5 after sintering, except the mixtures milled for 5 and 10 hours. The SEM observations showed the typical morphology of rod-like Al2TiO5 vary in the range: widths from 0.6 to 1.2 μm, and lengths from 3.0 to 6.0 μm. The rod-like Al2TiO5 formation was attributed to the positive effects caused by the mechanical activation.

scholarly journals THE PHYSIOLOGICAL AND HYGIENIC EVALUATION OF THE OPERATOR’S WORKING CONDITIONS IN THE SYNTHESIS OF CHROMIUM DISILICIDE NANOCRYSTALLINE POWDERS BY HIGH-ENERGETICAL MECHANOACTIVATION METHOD

2017 ◽  
pp. 89-95
Author(s):  
A. P. Yavorovskiy ◽  
N. V. Solokha ◽  
O. V. Demetskaya ◽  
I. M. Andrusishina
Keyword(s):  
Mechanical Activation ◽  
Technological Process ◽  
Working Conditions ◽  
Ball Mill ◽  
High Energy ◽  
Working Environment ◽  
Planetary Ball Mill ◽  
Emission Spectrometry ◽  
Activation Process ◽  
Plant Design

Objective: to carry out the physiological and hygienic evaluation of the working conditions of operators producing chromium disilicide nanopowders by high-energetical mechanoactivation method and to develop the preventive recommendations. Material and methods. The object of research was the technological process of producing nanocrystalline chromium disilicide powder within a planetary ball mill. The hygienic assessment of the technological process, technological equipment and psycho-physiologic evaluation of the working environment of the operators were carried out using the generally accepted psychophysiological, hygienic, and chronometer methods of study. The concentration of nanoparticles in the working area was measured using the diffusion aerosol spectrometer DAS-2702 («Aeronanoteh», Russia), the nanopowder particle size was measured by the device Analysette 12 DynaSizer («Fritsch», Germany), the chemical composition of air samples was determined by atomic emission spectrometry with inductively coupled plasma (ICP-AES) using the device «Ortima 2100 DV» («Perkin-Elmer», USA). Results. It was found out for the first time that the mechanical activation process was accompanied by emission of nano-sized chromium into the air of the working area, which had not been detected before the beginning of the work. The total concentration of nanoparticles in the main room was 1.6-1.9 times higher than that in the working area of the planetary ball mill and exceeded the test levels recommended for nanomaterials in European countries. Conclusion. The basic adverse factors in case of producing nanopowder of chromium disilicide by mechanoactivation method are presence of nanoparticles of metals in the workplace air and intensity of work. We have proposed hygienic recommendations which are aimed at improving the plant design for the high-energy mechanical activation in the direction of ensuring tightness, reduction of manual work operations, audible and visual signaling during the technological process.

Sign in / Sign up

Export Citation Format

Share Document