Effects Of Material Characteristics Research Articles

Review: Effect of Material Characteristics, and Process Conditions in Reducing Gaseous Pollutants Using Fly Ash (FA)-Based Adsorbent

The intensive use of fossil fuels has led to a significant increase in air pollution, which negatively affects human health and the environment. Fly ash (FA), a byproduct of coal combustion, has great potential as an adsorbent for hazardous gas pollutants due to its physical and chemical properties. This research aims to evaluate the effectiveness of fly ash as an adsorbent in reducing gas pollutants such as CO2, SO2, and NO2, as well as to examine the influence of temperature and material characteristics on adsorption capacity. The results indicate that the maximum adsorption capacity for each gas pollutant is achieved at different temperatures, fly ash demonstrating the highest performance at 150 °C for CO2 adsorption, achieving an efficiency of 94.7%. For SO2 and NO2, the optimum temperatures are 200 °C, with efficiencies of 72.17% and 100%, respectively. This study also emphasizes the importance of selecting the appropriate characteristics of the adsorbent material to enhance adsorption efficiency. This finding has the potential to support the development of more efficient and sustainable air pollution reduction technologies in the future, by utilizing industrial waste such as fly ash as an innovative solution.

Effects of Material Characteristics on Nonlinear Dynamics of Viscoelastic Axially Functionally Graded Material Pipe Conveying Pulsating Fluid

Effects of Material Characteristics on Nonlinear Dynamics of Viscoelastic Axially Functionally Graded Material Pipe Conveying Pulsating Fluid

Effects of material characteristics on thermal stress around an equiangular polygonal hole in a thermoelectric material

AbstractIn this study, we conducted a theoretical analysis of thermal stress around an arbitrarily shaped hole in a thermoelectric material under electric current density and energy flux loading. Based on complex variable methods, conformal mapping, and analytical continuation theorem, the exact solutions of the thermal stress around a hole were obtained for the Seebeck coefficient and electric and heat conductivity. Based on the conversion efficiency equation of thermoelectric materials, higher electrical conductivity and lower heat conductivity should be selected to achieve an optimal design. The theoretical results indicated that higher electrical conductivity could reduce the thermal stress around the hole. However, energy flux and thermal stress concentration might be generated around the adiabatic hole due to the presence of a matrix with lower heat conductivity. Hence, thermoelectric materials with lower thermal conductivity should be selected carefully to avoid premature failure around the hole caused by thermal stress concentration. Finally, we also obtained and discussed the stress intensity factors of a hypocycloid-type crack.

XGBoost model as an efficient machine learning approach for PFAS removal: Effects of material characteristics and operation conditions

Due to the implications of poly- and perfluoroalkyl substances (PFAS) on the environment and public health, great attention has been recently made to finding innovative materials and methods for PFAS removal. In this work, PFAS is considered universal contamination which can be found in many wastewater streams. Conventional materials and processes used to remove and degrade PFAS do not have enough competence to address the issue particularly when it comes to eliminating short-chain PFAS. This is mainly due to the large number of complex parameters that are involved in both material and process designs. Here, we took the advantage of artificial intelligence to introduce a model (XGBoost) in which material and process factors are considered simultaneously. This research applies a machine learning approach using data collected from reported articles to predict the PFAS removal factors. The XGBoost modeling provided accurate adsorption capacity, equilibrium, and removal estimates with the ability to predict the adsorption mechanisms. The performance comparison of adsorbents and the role of AI in one dominant are studied and reviewed for the first time, even though many studies have been carried out to develop PFAS removal through various adsorption methods such as ion exchange, nanofiltration, and activated carbon (AC). The model showed that pH is the most effective parameter to predict PFAS removal. The proposed model in this work can be extended for other micropollutants and can be used as a basic framework for future adsorbent design and process optimization.

Effect of material characteristics on thermal, tribological and mechanical properties of high temperature cast iron coatings

Coating is a desideratum part of material science and effort must be entailed for obtaining desired high temperature properties. Properties of high temperature cast iron coatings depend on various factors and each of them must be precisely tailored for meeting the huge industrial demand. The unlimited architecture of novel materials has led to growth of various coating with tailored properties. Single/multi layered structure offers remarkable possibilities to improve coating properties. Cast iron has been increasingly used in gas turbine, internal combustion engine manufacturing industries due to its low cost and structural strength. Numerous researches have been done on cast iron coatings to study the thermal, tribological plus mechanical properties. Novel material for improving the thermal, mechanical and tribological properties of Thermal barrier coatings (TBCs) required an extensive property-characteristics connection realization. Yttria Stabilized Zirconia (YSZ) is the most established coating material for thermal barrier application. YSZ alone cannot withstand the huge industrial demand. YSZ in engine application suffers failure due to non-uniform thermal field, thermal stress and sintering during the cycle of operation. YSZ cannot withstand engine thermal properties including thermal cycle life and thermal durability. Wear rate gets affected as a result of brittle fracture, speed of operation and abrasion. High temperature exposure leads to microcracks and this affects the mechanical properties. TBCs are usually made of ceramic top coat and it suffers failure. Few material characteristics and factors include thermal aging, fracture toughness of the material. This paper summarizes confirmed experimental results by researchers concerning different factors including thermal conductivity, thermal shock resistance, thermal cycle life, wear resistance, coefficient of friction, hardness and material characteristics in regard with cast iron coatings for high temperature applications. This paper also recommends feasible materials and material combinations to overcome certain limitations and failures.

Squeeze flow in multilayer polymeric films: Effect of material characteristics and process conditions

AbstractIn this work, effects of sealing temperature, time, pressure, as well as sealant thickness and viscosity on squeeze out flow (SOF) in heat sealing were examined. A new image analysis approach is presented to quantify SOF in heat sealing. It was found that increasing temperature or pressure could improve SOF but only in thick 130 μm sealants and reducing the sealant thickness to 50 μm suppressed SOF. Reducing viscosity in 50 μm sealant films was also found to improve SOF only at high‐sealing pressure and long sealing times. Three approaches were used to model SOF: analytical one‐dimensional model, numerical one‐dimensional model using finite difference method (FDM), (iii) Numerical two‐dimensional model using finite element analysis. Heat transfer was modeled, and it was shown that heat transfer induces a delay in SOF. When the FDM and the heat transfer models were combined, a good agreement between experimental and model prediction could be obtained. In addition, modeling results showed that SOF occurred in shear rates within the transition region between the Newtonian and Power‐law regions. This indicates the importance of considering the Carreau‐Yasuda fluid behavior in modeling of SOF.

Mechanism of overcoming plugging and optimization of parameters for rigid-flexible coupled elastic screening of moist fine coal

Deep screening is an important way to achieve the efficient classification of moist fine coal. In this process, there is often a problem of plugging of the screen surface. In this study, the rigid-flexible coupled elastic screening method was applied herein to overcome plugging. The mechanical model of plugging particles and the related mechanical equation were established, and the mechanism to overcome the plugging was clarified. The effects of material characteristics on screening performance and the related mechanisms were explored. The comparison experiment of rigid-flexible coupled elastic screening and rigid screening for 3 mm moist fine coal was carried out. Furthermore, the spatial distribution of particles during the screening process was further clarified. When the external moisture content was 11.31%, the screening efficiency reached 83.15%, and the total misplaced materials was 6.40%, which effectively improved the screening performance of moist fine coal.

Effects of material characteristics on the structural characteristics and flavor substances retention of meat analogs

The production of meat analogs using high moisture extrusion cooking is a complex process that depends on the properties of the protein ingredients. The aim of the study was to investigate the effect of different moisture and wheat gluten contents on the retention of volatile flavor substances, microstructure, moisture distribution, and secondary protein structures of meat analogs produced by the high moisture extrusion process. The high moisture extrusion trials were carried out using a soy protein concentrate with 0%, 10%, 20%, 30, and 40% added wheat gluten (by dry mass) or 50%, 60%, 70, and 80% moisture. The comparisons revealed that the retention rates of volatile flavor substances from large to small were generally represented by esters, alkanes, alkenes, phenols, aldehydes, and alcohols, under the same extrusion conditions. The wheat gluten and moisture contents affected the flavor characteristics of the meat analogs by affecting the microstructure, the binding capacity of internal proteins and water molecules, and the secondary structure of the proteins. The higher retention rates of the volatile flavor substances were observed in meat analogs produced by raw material with higher wheat gluten content and lower moisture content. Our findings show that wheat gluten and moisture contents of the raw material regulate the retention rate of volatile flavor substances by affecting the microstructure, water distribution, protein structure, and interactive force of the meat analogs, opening up a wide range of products for different consumer requirements.

Effect of Material Characteristics on PMDC Motors based on the Grade of Electrical Steel Sheet

In this study, the effect of the material characteristics of electrical steel sheet on permanent magnet direct current (PMDC) motors is investigated using finite-element analysis. The motor design and test results are examined and verified through fabrication. The characterizations of brushless direct current (BLDC) motors according to the materials used in their cores have been actively studied. On the other hand, the effect of material characteristics on a PMDC motor consisting of brushes and commutators has not been studied as much. In the case of the PMDC motors, electrical steel sheets are infrequently used because this motor is relatively smaller than the BLDC motor. However, the iron loss characteristics, which are proportional to the frequency and the magnetic flux density, affect the efficiency even in small motors. Further, the output of the motor changes owing to saturation due to iron loss. The outcome presented in this study provides core materials selection guidelines to improve motor efficiency.

Simulation Studies on the Effect of Material Characteristics and Runners Layout Geometry on the Filling Imbalance in Geometrically Balanced Injection Molds.

Simulation studies were performed on filling imbalance in geometrically balanced injection molds. A special simulation procedure was applied to simulate properly the phenomenon, including inertia effects and 3D tetrahedron meshing as well as meshing of the nozzle. The phenomenon was investigated by simulation using several different runner systems at various thermo-rheological material parameters and process operating conditions. It has been observed that the Cross-WLF parameters, index flow, critical shear stress (relaxation time), and zero viscosity, as well as thermal diffusivity and heat transfer coefficient strongly affect the filling imbalance. The effect is substantially dependent on the runners’ layout geometry, as well as on the operating conditions, flow rate, and shear rate. The standard layout geometry and the corrected layout with circled element induce positive imbalance which means that inner cavities fills out faster, and it is opposite for the corrected layouts with one/two overturn elements which cause negative imbalance. Generally, for the standard layout geometry and the corrected layout with circled element, an effect of the zero shear rate viscosity η0 is positive (imbalance increases with an increase of viscosity), and an effect of the power law index n and the relaxation time λ is negative (imbalance decreases with an increase of index n and relaxation time λ). An effect of the thermal diffusivity α and heat transfer coefficient h is negative while an effect of the shear rate is positive. For the corrected layouts with one/two overturn elements, the results of simulations indicate opposite relationships. A novel optimization approach solving the filling imbalance problem and a novel concept of global modeling of injection molding process are also discussed.

Effects of material characteristics and clearance size on dynamics of a slider-crank mechanism with two sliders and revolute clearance joints

This article presents influences of clearance size and material parameters on the dynamic response of a slider-crank mechanism with imperfect revolute joints in dry contacting condition. The mechanism was created by Solidworks and a finite element method in ANSYS software was used to analyze the effects which presented and discussed. The simulation results revealed that the acceleration of two sliders was obviously shaking with high peaks when the clearance size equal to 0.3 mm which differ from the ideal joint. Moreover, the smaller Young’s modulus material of journals indicated the significant effects on acceleration of mechanical systems. The reasons are due to a suddenly increase of contact force when the journal impacted into the bearing in imperfect revolute joints. The simulation results for the clearance size equal to 0.1 mm, 0.2 mm and 0.4 mm were close to an ideal joint. It demonstrated that clearance size and material characteristic played an important role in dynamics analysis of mechanical systems.

A Composite Photocatalyst Based on Hydrothermally-Synthesized Cu₂ZnSnS₄ Powders.

A novel composite photocatalyst based on Cu2ZnSnS4 (CZTS) powders was synthesized and investigated for use as a photocatalyst. CZTS powders were first made using a conventional hydrothermal method and were then used to grow silver nanoparticles hybridized onto the CZTS under various conditions through a microwave-assisted hydrothermal process. After the obtained samples were subsequently mixed with 1T-2H MoS2, the three synthesized component samples were characterized using X-ray diffractometry (XRD), scanning electron microscopy, transmission electron microscopy (FE-SEM, FE-TEM), UV-visible spectroscopy (UV-Vis), Brunauer-Emmet-Teller (BET), photoluminescence spectroscopy (PL), and X-ray photoelectron spectroscopy (XPS). The resulting samples were also used as photocatalysts for the degradation of methylene blue (MB) under a 300 W halogen lamp simulating sunlight with ~5% UV light. The photodegradation ability was greatly enhanced by the addition of Ag and 1T-2H MoS2. Excellent photodegradation of MB was obtained under visible light. The effects of material characteristics on the photodegradation were investigated and discussed.

Epitaxy and Microstructure Evolution in Metal Additive Manufacturing

Metal additive manufacturing (AM) works on the principle of incremental layer-by-layer material consolidation, facilitating the fabrication of objects of arbitrary complexity through the controlled melting and resolidification of feedstock materials by using high-power energy sources. The focus of metal AM is to produce complex-shaped components made of metals and alloys to meet demands from various industrial sectors such as defense, aerospace, automotive, and biomedicine. Metal AM involves a complex interplay between multiple modes of energy and mass transfer, fluid flow, phase change, and microstructural evolution. Understanding the fundamental physics of these phenomena is a key requirement for metal AM process development and optimization. The effects of material characteristics and processing conditions on the resulting epitaxy and microstructure are of critical interest in metal AM. This article reviews various metal AM processes in the context of fabricating metal and alloy parts through epitaxial solidification, with material systems ranging from pure-metal and prealloyed to multicomponent materials. The aim is to cover the relationships between various AM processes and the resulting microstructures in these material systems.

Effect of morphology on fracture toughness of unsaturated polyester-based hybrid nanocomposites

A hybrid ternary system of thermoplastic/clay/thermoset was synthesized to produce a tougher unsaturated polyester without reducing the glass transition temperature or the elastic modulus. The effects of material characteristics and morphology on fracture toughness were explored. Three synthesis variables control these characteristics: the ratio of methyl methacrylate to styrene used as curing agents, clay loading, and the content of a thermoplastic copolymer of styrene and methyl methacrylate. Specific ranges of these variables were chosen to minimize the effect of the characteristics of each phase on fracture toughness in order to evaluate the influence of morphology. The thermoplastic component contains the vast majority of the silicate layers and forms a second phase, dispersed throughout the continuous thermoset-rich phase. These particles can perturb the propagating crack front causing crack deflection and/or crack pinning where the latter mechanism provides a large increase in fracture toughness of unsaturated polyester. Clay loading is the most important factor on the fracture mechanism by affecting the impenetrability of the thermoplastic-rich particles and the morphology. A non-monotonic correlation between fracture toughness and the ratio of thermoplastic-rich particle radius to interparticle distance is developed allowing for the design of hybrid nanocomposites with desired toughness.

Investigation of functional properties and color changes of corn extrudates enriched with broccoli or olive paste.

Following the tendency of replacing common food snacks with healthier food products, extruded snacks with corn flour and broccoli (4-10%) or olive paste (4-8%) were investigated in this study. The effect of material characteristics, including feed moisture content (14-19%), and broccoli or olive paste concentration, and extrusion conditions, including screw speed (150-250 r/min), and extrusion temperature (140-180 ℃), on the functional properties (water absorption index, water solubility index, and oil absorption index), as well as color change (ΔE) of the extruded snacks was studied. Regression analysis showed that screw speed did not significantly influence (p > 0.05) the properties. After mathematical modelling it was found that broccoli and olive paste concentration, as well as temperature increment, caused a decrease in water absorption index (minimum of 5.6 and 6.4 g/g sample, respectively) and an increase in water solubility index (maximum of 18.7 and 10.9 g/100 g sample, respectively), while feed moisture presented opposite tendency. Higher extrusion temperature led to an increment of oil absorption index (approximately to 1.2 and 1 mL/g sample) and decrement of color changes. Finally, feed moisture and broccoli concentration lowered oil absorption index and color of corn/broccoli extrudates, while olive paste concentration caused their increment.

Methodology and verification of calculations for contact stresses in a wheel–rail system

The distribution of contact stresses in the wheel–rail system is a decisive factor for the wear of elements and the safety of rail transport. Analytical calculations of stresses based on the Hertz theory can only be applied to elastic deformation of materials. High dynamic loads leading to plastic deformation (not considered in the Hertz theory) are a predominant cause of problems in the contact vicinity. These problems can be successfully resolved by applying the finite-elements method. Two- and three-dimensional test models were generated to estimate an error in numerical calculations in the MSC.MARC program. We compared the results of numerical calculations with analytical calculations. Based on the obtained results we defined the effect of parameters describing the finite-elements mesh on the calculation error for contact stresses, and adjusted mesh parameters appropriately to achieve as low as possible error in numerical calculations. We also defined the effect of material characteristics on the value of contact stresses on the wheel–rail interface.

Plastic-Bending of Adhesively Bonded Dissimilar Sheet Metals

In this paper, the effect of material characteristics on plastic forming of adhesively bonded dissimilar sheet metals was investigated by experiments and finite element method (FEM). The acrylic adhesive employed in the experiments has visco-plasticity characteristics with high ductility and strong strain-rate and temperature sensitivity in strength. Major results obtained are summarized as follows: (1) In the adhesively bonded dissimilar sheet metals, the gull-wing bend and the shear deformation of the adhesive layer are suppressed by the combination of the sheet metals when a bending inside sheet has high-tensile strength. (2) The gull-wing bend is suppressed by high-speed forming at a lower temperature as well as the same kind of sheet metals. (3) The calculated results using MSC Marc2010 are relatively good agreement with the experimental results.

노즐 특성에 따른 후방동체 온도 변화 연구

In order to enhance the aircraft survivability, infrared signatures emitted by engine parts should be diminished. For its reduction it is necessary for the rear fuselage temperature to be decreased. In this study, numerical modeling of flow fields and heat transfer of nozzle is performed and its temperature distribution along each component wall is predicted. The effects of material characteristics and shape of nozzle wall and radiation shield on the heat transfer are also investigated. Through this numerical analysis, design parameters related to the susceptibility of aircraft are examined.

Modeling of phase transitions in three-phase polymorphic systems: Part II. Effects of material characteristics on transition rates

Abstract

In-Situ X-Ray Characterization of Fiber Structure during Melt Spinning

The properties of a polymer are strongly influenced by its morphology. In the case of fibers from semi-crystalline polymers this consists of the degree of crystallinity, the spacing and alignment of the crystalline regions, and molecular orientation of the polymer chains in the amorphous regions. Information on crystallinity and orientation can be obtained from X-ray analysis. In-situ X-ray characterization of a polymer during the melt spinning process is a major source of information about the effects of material characteristics and processing conditions upon structure evolution along the spinline, and the final structure and properties of the end product. We have recently designed and installed an X-ray system capable of in-situ analysis during polymer melt spinning. To the best of our knowledge this system is unique in its capabilities for the simultaneous detection of wide angle and small angle X-ray scattering (WAXS and SAXS, respectively), its use of a conventional laboratory radiation source, its vertical mobility along the spinline, and its ability to simulate a semi-industrial environment. Setup, operation and demonstration of the capabilities of this system is presented herein as applied to the characterization of the melt spinning of isotactic poly(propylene). Crystallinity and crystalline orientation calculated from WAXS patterns, and lamellar long period calculated from SAXS patterns, were obtained during melt spinning of the polymer along the spinline.