Size Reduction Process Research Articles

Effect of Size Reduction Processes on Rice Flour Properties and the Quality of their Bakery Products

Currently, there is an incremental demand for ricebased products among health-conscious consumers in the dynamic food market. The method and the machinery used in the size reduction processes have a crucial impact on the physicochemical properties of rice flour, thereby affecting the quality and consistency of the final products. Consequently, certain starch modification techniques can be implemented to eliminate some baker-unfriendly properties associated with rice flour. This brief review is focusing on literature pertaining to different rice milling techniques, certain physicochemical and functional flour properties, a comparison of rice flour properties relevant to different rice milling techniques, the relationship between different rice flour properties and their effect on the quality of bakery products, and finally the improvement of flour properties by different starch modification techniques.

Green Synthesis Gold Nanoparticles using Bioreductor of Butterfly Pea (Clitoria ternatea L.) Leaf Extract as an Antioxidant

Gold nanoparticles are inorganic metal materials in suspended solutions with a particle size reduction process to the 5-400 nm nanoscale range. Gold nanoparticles can be synthesized using the green synthesis method using a bioreductor of butterfly pea leaf infusion extract, which can be used as an antioxidant. This study aimed to determine the characteristics of gold nanoparticles using a UV-Vis spectrophotometer and TEM and to determine the antioxidant strength of gold nanoparticles through the IC50 value. This study used 20, 10, 5, and 2.5 ppm concentration variations. The results of the characterization of gold nanoparticles using a UV-Vis spectrophotometer showed a maximum wavelength of 550 nm, and the results of the TEM test showed a particle diameter of 6.58 nm. The antioxidant activity test was carried out using the 1,1-diphenyl-2-picryhydrazyl (DPPH) quenching method, resulting in % quenching at a concentration of 20, 10, 5 and 2.5 ppm of 76.3; 70.6; 85.5; and 92.9% and an IC50 value of 0.25 ppm which is included in strong antioxidants. It can be concluded that gold nanoparticles synthesized using butterfly pea leaf extract have the potential to be an effective antioxidant agent.

An Algorithm for Reversible Logic Circuit Synthesis Based on Tensor Decomposition

An algorithm for reversible logic synthesis is proposed. The task is, for a given n -bit substitution map, to find a sequence of reversible logic gates that implements the map. The gate library adopted in this work consists of multiple-controlled Toffoli gates with m control bits, where m ∈ {0, …, n − 1}. Controlled gates with large m (> 2) are then further decomposed into smaller gates ( m ≤ 2). A primary goal in designing the algorithm is to reduce the number of Toffoli gates which is known to be universal. The main idea is to view an n -bit substitution map as a rank-2 n tensor, and to transform it such that the resulting map can be written as a tensor product of a rank-(2 n − 2) tensor and the 2 × 2 identity matrix. It can then be seen that the transformed map acts nontrivially on n − 1 bits only, meaning that the map to be synthesized becomes ( n − 1)-bit substitution. This size reduction process is iteratively applied until it reaches a tensor product of only 2 × 2 matrices. The time complexity of the algorithm is exponential in n as most previously known heuristic algorithms for reversible logic synthesis are, but it terminates within reasonable time for not too large n which may find practical uses. As stated earlier, our primary target is to reduce the number of Toffoli gates in the output circuit. Benchmark results show that the algorithm works well for hard benchmark functions, but it does not seem advantageous when the function is structured. As an application, the algorithm is applied to find reversible circuits for cryptographic substitution boxes, which are often required in quantum cryptanalysis.

Rheological Bridge Zones: The Initialization of Strain Localization

Strain localization occurs across the crust in both brittle and viscous regimes, but the exact causes remain debated. Natural rock observations suggest that changes in phase properties (such as physical properties, phase distribution, and grain geometry) are more influential in weakening than variations in stress and temperature. Investigating the early stages of strain accumulation in various pressure-temperature conditions leads to a better understanding of these causes. Our study focuses on three weakly deformed rocks showing zones of localization on a millimeter or smaller scale, which we term “bridge zones”. These localized zones appear to mechanically connect weak domains and typically exhibit finer grain sizes within a narrow band. Importantly, these zones occur in less deformed rocks from the margins of shear zones. They result from both in-situ grain size reduction and chemical processes leading to phase mixing or element mobility on a limited spatial scale. Numerical modeling aligns high-stress areas with these zones, supporting their impact on reducing rock strength. We propose a conceptual model linking far-field loading to microscale changes in developing these zones. Characterization of bridge zones aids in elucidating the microstructural processes driving deformation localization, which is fundamental for plate tectonics, metamorphism, seismicity, and other lithospheric processes. This research reveals microscale mechanisms driving weak domain development, improving our knowledge of rheological changes and laying the groundwork for predictive models regarding strength evolution in the lithosphere.

Hard/stiff surface coatings for particle weakening, part I: Methodology

Size-reduction processes are essential for liberating valuable minerals yet energy-inefficient, which needs to be remedied by developing energy-efficient methods. This work is the first part of a wide study that (i) describes a surface coating method, namely, spray coating, and (ii) presents some preliminary results that hard or stiff surface coatings can be used to weaken softer ore particles. The hard surface coatings were achieved with a ceramic spray and two inorganic precipitates (CaCO3 and silica). The fracture energy and/or strength of spray-coated and uncoated particles was measured using the Short Impact Load Cell (SILC). Spray coating can only yield low surface coverage (up to 1–2% of the mass of particles), which is only apparent if particle surfaces are washed before coating. Nevertheless, the preliminary results suggest significant reductions in the fracture force and energy of soft ore particles after they are coated.

Production and characterisation of microfluidized olive powder

SummaryMicrofluidization has been gaining popularity as a size reduction process in recent years. In this study, microfluidization technique was used for olives to change the cell wall structure and decrease the size of oil droplets. Olive powders were produced from green, black and raw olives using freeze drying following microfluidization at 1200 bar. Antioxidant activity was not affected significantly for all powders while total phenolic content decreased for green and raw olive powders with microfluidization. Among all olive powders, the one raw olive gave the highest antioxidant activity and phenolic content. In microscopic analysis, Scanning Electron Microscope images revealed that microfluidization results in finer particles which are self‐encapsulated by trapping the oil droplets. Stability analysis through Turbi Scan and rheological measurements of the powder suspensions showed that microfluidization process enables more stable suspensions having higher water holding capacity. Herschel–Bulkley model was found for the flow behaviours of the olive powder suspensions.

RECOVERY OF BORON WASTES WITH INORGANIC ACID

Approximately 73-74% of boron mineral reserves all over the world are located in the Western Anatolian region of Turkey, in the provinces of Eskişehir, Kütahya, Balıkesir, and Bursa. The most intense minerals extracted from these fields are colemanite, ulexite, and tincal minerals, respectively. The general principle in the recovery of these minerals is to extract the raw ore and obtain it by size reduction processes of concentrates in high grade. In addition to concentrates, boric acid (H3BO3) production is also possible in Balıkesir and Kütahya. The production of this acid in question includes a series of processes from dissolution with sulfuric acid at high temperatures to crystallization. In this study, except for the aforementioned high concentrations, boron recovery from clay waste, which is high in boron content and is collected from plant waste ponds, is investigated. For this purpose, ulexite-colemanite-containing slime wastes of the Bigadiç (Balıkesir) Plant were dissolved in 7% solids at 60°C in different sulfuric acid concentrations (1-6% H2SO4) and were obtained with 83-97% B2O3 recovery. When the boron wastes are evaluated, issues such as the discovery and establishment of a new waste pond/dam will be solved, the valuable content in the wastes will be recovered, and the environmental problems of boron and other contents in clay will be eliminated. This article includes information about the characterization of the structure by considering the dissolution of boron and other compounds, as well as obtaining boric acid from inorganic acid and boron wastes.

Assessing the Impact of Preprocessing and Conversion Technologies on the Sustainable Aviation Fuel Supply from Forest Residues in the Southeast U.S.A.

Forest residues have been suggested as potential feedstock for sustainable aviation fuel (SAF) production through different pathways. However, the bulky density and scatter distribution require efficient size-reduction processes to enhance the feedstock supply. Thus, this study analyzes the impact of alternative preprocessing and conversion technologies on the SAF supply chains from logging residues (the predominant share of forest residues) using a two-stage mixed-integer linear programming model. The model determines the optimal location of biomass preprocessing depots, conversion facilities, and airports receiving SAF by minimizing the net present value of the total supply chain cost over 10 years. Using high-resolution spatial data in the Southeast U.S.A. as a case study, the results show that the technology and scale of the facilities heavily influenced the SAF’s breakeven cost and maximum supply quantity. The most economically efficient system that adopts a rotary shear milling system and pyrolysis conversion process could generate up to 650 million gallons of SAF from logging residues in the region, with nearly 62% of the SAF being produced from hardwood residues. Also, the most efficient system has an estimated breakeven cost of US$5.51 per gallon of SAF.

Performance Test of Coconut Shell Grinding Machine For Pyrolysis Process

Coconut shell is a solid waste of biomass from processed coconuts separated from the flesh. Coconut shells can be reprocessed into products of high economic value. Coconut shells can be processed for bio-oil production via high-temperature pyrolysis. In the pyrolysis process, the coconut shell raw materials are reduced in size to facilitate combustion. The aim of this research was to test the performance of the modified coconut shell grinding machine, determine the effect of water content on the milling process, achieve coconut shell sizes of 3, 5, and 10 mm to enhance the pyrolysis process, and analyze the economics of grinding machine engineering. The size reduction process was carried out using a custom-designed coconut shell grinder that was altered in its sieve section. The sieve sections had diameters of 10, 5, and 3 mm. The coconut shell to be ground had a moisture content of 8–10%. The grinding machine capacity varies with each size, namely 10 mm, 5 mm, and 3 mm, achieving throughput rates of 14.892 kg/h, 7.214 kg/h, and 2.94 kg/hour, respectively. The resulting yield was notably high, ranging from 95 to 96.780%, and the associated yield loss remained low, between 3.2% and 4.8%. During the material size tests, the working RPM was observed at 630.6 for 10 mm, 711.2 for 5 mm, and 1017.18 for 3 mm, and these RPM variations influence the grinding speed.

Insights in the Physicochemical and Mechanical Properties and Characterization Methodology of Perlites

Perlite is a volcanic glass that, under thermal treatment, expands, producing a highly porous and lightweight granular material which finds application in the construction, horticulture, insulation and other industrial sectors. Proper control of the feed properties and the expansion conditions allows the production of purpose-oriented grades, while the primary evaluation of its appropriateness for use in each sector is performed by the proper characterization of relevant physical, thermal or/and mechanical properties. However, due to its extreme fineness, low density, and friability, most of the available characterization methods either fail in testing or provide erroneous results, while for certain properties of interest, a method is still missing. As a consequence, the way towards the evaluation of the material is rife with uncertainties, while a well-defined methodology for the characterization of the critical properties is of practical importance towards the establishment of a pathway for its proper analysis and assessment. This article presents the available methodology for determining the main properties of interest, i.e., the size and density, water repellency/absorption and oil absorption, the microstructural composition, crushing and abrasion resistance and isostatic crushing strength, and also sampling and size reduction processes. The issues raised by the application of existing methods are analyzed and discussed, ending up to a proper methodology for the characterization of each property, based on the long-term experience of the Perlite Institute. The study is supplemented by updated insights on ore genesis, physicochemical properties, mineralogical composition and the expansion mechanism, as background information for the sufficient comprehension of the nature and properties of perlite.

СУБПІКСЕЛЬНЕ СКАНУВАННЯ ДЛЯ АНАЛІЗУ ЗОБРАЖЕНЬ СПЕКТРА

Subject and Purpose. In this paper, an algorithm is developed to improve the spectrum image resolution in the atomic emission spectrum registration using multi-element detectors and taking multiple exposures with image shifting by a fractional part of a pixel. Methods and Methodology. Mathematical modeling techniques are employed in the coordinate representation dictated by the prior information. The modeling results are checked by experiment. Results. The importance of the resolution value of spectral image registration systems and its impact on the quality of the obtained results have been highlighted. The spectral informativeness of the regularly (matrix- or linearly) structured multi-element detectors has been evaluated against the irregular-structure sensors, such as photographic emulsions. As it has been found that the process of pixel size reduction is demanding, an alternative approach through subpixel image shifting has been proposed. Unlike the case of the corresponding instruments implemented as a rule in the frequency domain, here the relevant theoretical problem reduces to the over- determined system of linear equations. The proposed solution algorithm employs the least squares method having regard to the prior data specificity posed by the isolation of the spectral lines and a smooth flow of the background between them. The digital simulation results and the real experimental evidence from the atomic emission spectral analysis have been presented, illustrating the algorithm operation. The experimental research was carried out for one-dimensional spectrum images registered with linear charge-coupling photodetectors. The so gained resolution was twice the spatial resolution of the photodetector. Conclusions. It has been demonstrated that controlled image shifting not only improves the photometry accuracy but also significantly enhances the detector resolution. The general comparisons of the theory with the experiment have proved the feasibility of bringing the proposed methodology into atomic emission analysis.

Foam in grinding and role of ground mineral in its stability

AbstractSurfactants are usually used as grinding aids. However, surfactant foaming during the grinding process is rarely mentioned in the literature with no clarification of its effect on the grinding process. In this paper, the generation of foam during the grinding of talc and quartz, as two different minerals in their hardness and hydrophobicity, was observed in the presence of sodium dodecyl sulfonate (SDS). The effect of generated foam on the fineness of ground product under different grinding conditions such as solids%, grinding time, and pulp pH was investigated. The results indicated that the foam was formed during the grinding of both minerals. The foam volume depends not only on the presence of surfactant but also on the characteristics of the mineral along with grinding conditions. The foam was intense and more stable particularly at pH 10 and high solid content (i.e., 60% solids) in the case of talc due to its fineness and hydrophobicity that result in bubbles stabilization. Remarkably, there is no foam at acidic pH due to the high ionic strength that leads to bubble instability. Most importantly, the presence of surfactant foams improves the size reduction process by providing more dispersion of particles, as one of the grinding aid mechanisms, due to particle‐particle and particle‐SDS repulsive electrostatic forces.

The Effects of Ball-Mill Grinding Parameters on Lignite Morphology

In recent years, because of the decreasing liberation sizes of the minerals, processes such as grinding need to be evaluated in more detail. As is well known, size reduction processes are very important both in mineral processing and in many industrial applications. However, to increase the efficiency of the processes after size reduction, variations in particle morphology should also be evaluated, along with particle size. Although the effectiveness of grinding media (ball, rod, autogenous) has been shown for different materials, there are very few studies on the effect of the powder/grinding media ratio and grinding time on particle morphology in terms of shape factor and roughness values. This study aims to investigate the variations in the morphology of lignite samples under different grinding conditions such as grinding time and powder/grinding media ratio (U). The results of these analyses showed that while the d80 size of the ground lignite was 1.1 mm after 2 min grinding time, it decreased to 0.5 mm following 15 min grinding time. The roundness values of particles vary in the range of 0.746–0.790 with increasing grinding time. In addition to the grinding time, while the roundness of particles was found to be 0.739 for 0.34 U values (powder/grinding medium rate), it increased to 0.788 when the U value was adjusted to 0.67. The average roughness (Ra) values of particles increased from 60.9 nm to 107.9 nm upon increasing the grinding time from 2 min to 16 min. Due to these findings, it can be suggested that lignite samples became rounder with increasing grinding times, and roughness analyses made in a 10 × 10 μm surface area with an Atomic Force Microscope (AFM) indicated that particle roughness increased in direct proportion to grinding time.

Kinetics of Grain Size Reduction in Minerals Undergoing Ball Milling

AbstractThis work focuses on the grain size reduction induced by ball milling in individual minerals and binary mixtures containing quartz and a softer mineral. All the investigated minerals and mineral mixtures undergo a significant monotonic grain size decrease upon mechanical processing. The rate at which the process occurs in individual minerals decreases with the hardness of the mineral phase. Hardness is shown to play a crucial role also in the case of mineral mixtures. The final grain size attainable by the softer mineral as well as the rate of the grain size reduction process depend, indeed, on the amount of quartz in the mixture. A kinetic model allows rationalizing the observed behaviour based on the intensity of mechanical stresses generated during individual impacts.

Quantifying the relationship between particles' strength and their mineralogical and textural characteristics

Advances in ore characterisation methods, such as automated mineralogy and core scanning technology, as well as in the breakage characterisation field, suggest that the relationship between the ore characteristics and its comminution behaviour can be thought of differently. This study focuses on developing a relationship that allows the transformation of the quantitative characterisation of rock particles (i.e., mineralogical and textural measurements) into particle strength. This study characterised ten different ore types using quantitative methods (i.e., SEM-based technologies and image analysis). At the same time, the strength of particles was collected from physical specimens tested in the SILC over a limited range of particle sizes (3 to 16 mm). The analysis of the databases shows that none of the characteristics has total control over the strength of particles. However, the shape of the grains and the contrast of the physical properties of minerals that compose the particles seem to be more significant in predicting the particles' strength of these rocks. In addition, the model was more successful in predicting particle strength for most rocks with more regular grain sizes, indicating that this parameter requires further comprehension.This research shows that ore characterisation data has the potential to be used to predict the strength of rocks' particles up to a millimetre scale, which is relevant to comminution, which would allow a direct link to be established between the plant and ore characteristics at the particle scale. However, more experimental and numerical studies are needed to develop a predictive and generalised model from quantitative ore characterisation data that may allow improving the modelling of the comminution stage by incorporating more resolution to the system and reducing the laborious work of comminution testing, helping to optimise the whole size reduction process.

Development of Amphibole Crystal Preferred Orientations (CPOs) and Their Effects on Seismic Anisotropy in Deformed Amphibolites

AbstractCrystal preferred orientations and seismic anisotropy of amphibole play a crucial role in fingerprinting the rheological and physical properties of the deep crust. This study presents typical naturally deformed (banded, mylonitic, and ultramylonitic) amphibolites from the Ailao Shan‐Red River shear zone (ASRR‐SZ), southwestern China. In the banded amphibolite, coarse amphibole grains are highly elongated by dislocation creep and develop type I fabric of amphibole. In the mylonitic amphibolite, amphibole grains are characterized by porphyroclasts with core‐mantle structure and fine‐grained amphiboles in the matrix. Subgrain rotation recrystallization dominantly contribute to the grain size reduction process and display type III fabric of amphibole. In the ultramylonitic amphibolite, the fine‐grained amphiboles are mainly deformed by mechanical rotation of prismatic grains and develop type IV amphibole fabric. The seismic anisotropies are calculated from crystal preferred orientation (CPO) of naturally deformed amphiboles and model fabric. They both display that the transition of amphibole fabric from type III through type I to type IV also comes along with the transition of AVp patterns from Vp(X) ∼ Vp(Y) > Vp(Z) through Vp(X) > Vp(Y) > Vp(Z) to Vp(X) > Vp(Y) ∼ Vp(Z). Under the same texture strength, the strongest seismic anisotropy (both AVp and Max. AVs) occurs in the type III fabric of amphibole, the weakest seismic anisotropy is related to type IV fabric and a medium seismic anisotropy in type I fabric. This work indicates that the CPO types of amphiboles need be carefully considered in interpreting observed seismic anisotropy at the deep crustal level.

Solution‐Processed Synthesis of Nano‐Sized Argyrodite Solid Electrolytes with Cavitation Effect for High Performance All‐Solid‐State Lithium‐Ion Batteries

AbstractInvited for this month's cover picture is the group of Dr. Jun‐Ho Park. The cover picture shows a particle size reduction process of Li6PS5Cl solid electrolyte with a cavitation bubbling effect during a novel solution‐processed synthesis. By reducing the particle size of the solid electrolyte, it is possible to increase the contact area between the two materials and reduce the interfacial resistance between cathode and electrolyte materials. Read the full text of the Research Article at 10.1002/batt.202300036.

Cover Picture: Solution‐Processed Synthesis of Nano‐Sized Argyrodite Solid Electrolytes with Cavitation Effect for High Performance All‐Solid‐State Lithium‐Ion Batteries (Batteries & Supercaps 4/2023)

The Front Cover shows a particle size reduction process of LPSCl solid electrolyte with a cavitation bubbling effect during a novel solution-processed synthesis, for practical application in all-solid-state cells. More information can be found in the Research Article by S.-M. Lee, J. In Lee, J.-H. Park and co-workers.

Size reduction process by novel TVA technique and its effect on enhancement of physical properties of oxide semiconductor pellets

ABSTRACT This work describes a novel approach that can reduce grain as well as particle size of semiconducting pellet samples in the nanoscale range with low-cost and less instrumentation. Herein an instrumental setup was designed and fabricated in-house, referred to as the ‘Thermo-Vibrational Annealing’ (TVA) setup. Here, the concept of grain confinement within the pellet during the recrystallisation phase of annealing was achieved by simultaneously applying both thermal and vibrational mechanical energy to the sample, followed by vibrational dry quenching. In this work, for the case study, ZnO pellets were prepared by using chemical route pyrophoric method followed by annealing at 800°C for 4 hours using this setup. The reduction of particle and grain size by this TVA, in comparison to without vibrational annealing, was confirmed by X-ray diffraction (XRD), high-resolution transmission electron microscopy and scanning electron microscopy studies. The expected changes in other microstructural and optical properties were examined by Raman and UV-Visible absorption spectroscopy studies. Moreover, this work gives references to improve the physical properties not only of ZnO but also of other oxide semiconductor samples using this technique, to be used in multiple sensors and optoelectronic devices.

Three-dimensional numerical simulation of heating and melting behaviors of cerium oxide powders in radio frequency thermal plasma

The present study aims at the numerical simulations of the melting process of cerium oxide particles in RF thermal plasma. The physical model and the calculating method were described firstly; the interaction between cerium oxide particles and plasma was analyzed; specific attention was given to the effects of particle initial size, injection velocity on the particle melting and trajectory in plasma. The influence of the temperature field and velocity field distribution of the plasma around the particle trajectory on the melting effect is analyzed, and the relationship between the heat absorption efficiency of the particles and the particle size reduction process is further determined. It is also found that there exists an optimal particle initial injection velocity which led to a more concentrated final particle size distribution and a more significant reduction of particle size. The results could provide effective guidance for understanding the plasma spheroidization process of uranium dioxide and cerium dioxide powder particles.