Condition For Materials Research Articles

Design, Fabrication and Performance Evaluation of a Poultry Feed Pelleting Machine

The poultry industry plays a crucial role in meeting the global demand for animal protein. To ensure optimal growth and productivity of poultry, the formulation and processing of high-quality feed are essential. Feed pelleting is a common method employed to enhance the nutritional value, digestibility, and handling characteristics of poultry feed. The machine which meant for the production of poultry feed pellets in good quantities, was designed, fabricated and its performance evaluation was carried out accordingly. The independent dual operated Poultry Feed Pelleting Machine permits constant production line since the prime mover (diesel engine) would be plunged into operation as at when due, that is, when electricity power supply failed. The materials used were locally sourced which included; mild steel, high carbon steel, aluminum, 3hp electric motor, prime mover and axle. The base materials are corn, soybean, wheat, rice bran, wheat bran, herbs, fish meal, groundnut cake etc. The machine functioned reliably at the throughput capacity of 95kg per hour and up to 800kg per day with 95% efficiency proved its high performing rate. Moreover, the study showed that useful information in designing pelleting machine that produced pellet optimally when the appropriate moisture condition for feed materials is considered ranging from 20% - 30% with temperature range of 500C-700C. The results indicate that the developed machine offers significant advantages in terms of pellet quality, production efficiency, and energy consumption compared to conventional pelleting methods. The developed machine is recommended to facilitate the production of poultry feed pellets for small scale and medium scale farmers.

Orthogonal decomposition of anisotropic constitutive models for the phase field approach to fracture

We propose a decomposition of constitutive relations into crack-driving and persistent portions, specifically designed for materials with anisotropic/orthotropic behavior in the phase field approach to fracture to account for the tension–compression asymmetry. This decomposition follows a variational framework, satisfying the orthogonality condition for anisotropic materials. This implies that the present model can be applied to arbitrary anisotropic elastic behavior in a three-dimensional setting. On this basis, we generalize two existing models for tension–compression asymmetry in isotropic materials, namely the ‘volumetric–deviatoric’ model (Amor et al., 2009) and the ‘no-tension’ model (Freddi and Royer-Carfagni, 2010), towards materials with anisotropic nature. Two benchmark problems, single notched tensile and shear tests, are used to study the performance of the present model. The results can retain the anisotropic constitutive behavior and the tension–compression asymmetry in the crack response, and are qualitatively in accordance with the expected behavior for orthotropic materials. Furthermore, to study the direction of maximum energy dissipation, we modify the surface integral based energy release computation, Gθ, to account only for the crack-driving energy. The computed energies with our proposed modifications predict the fracture propagation direction correctly compared with the standard Gθ method.

Essential Design Strength and Unified Strength Condition of ETFE Membrane Material

This study proposes essential design strength and unified strength condition for ETFE membrane materials based on the structural state-of-stress theory and formula of strength. Firstly, the tested strain data of the uniaxial rectangle-shaped specimen are modeled to obtain its state-of-stress characteristic parameter. Then, the characteristic points in the evolution curve of the characteristic parameter are detected by the cluster analysis (CA) criterion. The characteristic points are the embodiment of the natural law from quantitative change to qualitative change of a system, which define the essential strength and the essential design strength of ETFE membrane materials. Further, the essential principal stresses are derived at the characteristic points in the evolution curves of the characteristic parameters obtained by the state-of-stress analysis of the strain data from the tests of air bubbling models and cruciform specimens. Both essential principal stresses and essential strength lead to the unified formula of strength for ETFE membrane materials. Additionally, the unified strength condition is derived for the design of ETFE membrane material structures. Finally, the essential strength, essential design strength, and the unified strength conditions are compared with the existing conditions, providing a rationality to update the existing analysis and design methods for determining the strength of ETFE membrane materials.

Specific force map for smart machining applications with rotating tools

Industry 4.0 is the need of the hour in current global market scenario and all the processes are moving toward automation and smart manufacturing. In machining, smart techniques implementation depends on developing a database for decision-making, which is the case for stack drilling in aerospace industry. In this application, choosing one optimal condition for several materials is a challenge due to their different machinability. Hence, material identification techniques are suitable approaches for adapting the cutting parameters in real time, which improves tool life, hole quality, and productivity. In that regard, the goal of the present paper is to create a specific force data map for axial drilling and circular milling processes based on its experimental force and power measurements. To do that, experiments were separately carried out on Titanium and Aluminum workpieces in a range of cutting speed and feed conditions. The results show that specific cutting and feed forces for each material can be identified on distinct regions of the map, without thresholds overlapping. Given that, these maps can be used as a signature to distinguish two metallic materials in real time machining. In this case, the specific data points at the interface layers may offer advantage to accurately identify tool position unlike monitoring gradient of feed forces while drilling stacked materials. Therefore, smart machining techniques seeking cutting parameters optimization can be implemented for a particular material.

Lithium ferrite (Li0.5Fe2.5O4): synthesis, structural, morphological and magnetic evaluation for storage devices

Lithium ferrite Li0.5Fe2.5O4 has been synthesized by the use of the sol–gel technique. X-ray diffractometer (XRD) has been employed to confirm the crystal structure of spinel ferrites. No impurity peaks are detected in XRD graph, which confirms single phase crystal structure. The evaluation of grain size and analysis of external surface morphology of synthesized lithium ferrites has been done by scanning electron microscope (SEM). Average grain size was about equal to 131 nm. Energy dispersive x-ray spectra showed all the elements were present in required proportions. Magnetic characteristics such as saturation magnetization (Ms), remanence (Mr), and coercive force (Hc) have been measured from MH loops. Saturation magnetization has been measured to be 43.69 emu/by law of approach to saturation. The coercivity value lies in the range of few hundred Oersted which is vital condition for electromagnetic materials. Cyclic Voltammetry (CV) measurements were made, to know about the electrochemical performance of the material. CV results show that with the increase in scan rate specific capacitance decreases and the area of the loop increases which is promising for the formation of super capacitors and lithium-ion batteries (LIB's).

Noncentrosymmetric Ba6In2Q10 (Q = S, Se): Structural Chemistry and Nonlinear-Optical Activity.

The indispensable condition for laser frequency-doubling crystal materials is that they crystallize in the noncentrosymmetric (NCS) structures. Here, ternary NCS Ba6In2S10 (1) and Ba6In2Se10 (2) (P63) were synthesized via conventional solid-state reactions. Their zero-dimensional structures feature isolated InQ4 tetrahedra and Q22- (Q = S, Se) dimers that are separated by Ba2+ counter cations. The structural relevance and differences with the centrosymmetric Ba12In4S19 and Ba12In4Se20 are analyzed in detail. Both 1 and 2 show obvious laser frequency-doubling activity, and their optical band gaps are 3.72 and 1.78 eV, respectively. This work provides a new type of IR nonlinear-optical materials.

Ultrasonic renovation mechanism of spent LCO batteries: A mild condition for cathode materials recycling

Recycling of spent lithium-ion batteries was an important step for the utilization of waste electric and electronic equipment. Commonly studies mainly focused on metal extraction while bringing the waste of chemical reagents, secondary pollution, and energy consumption. The reasons for the failure of lithium-ion batteries were the pore blocking by organics and the structural collapse in LiCoO2 crystal. Ultrasonic hydrothermal renovation was a promising method to directly renovate spent LiCoO2 crystal structure and remove the organics. It combined the advantages of ultrasonic and hydrothermal technologies which were high-efficiency and clean production. Ultrasonic cavitation generated by high-powered ultrasonic in liquid phase was a process with bubble formation and implosion. Under the effect of ultrasonic cavitation and advanced oxidation synergistically, the blocked channels and layer structure were effectively rebuilt, the organics were removed and the crystal structure of LiCoO2 was renovated. This experimental result showed that the optimal renovation condition was at the ultrasonic power of 1050 W, the reaction temperature of 90 ℃, the reaction time of 6 h, 1 mL of H2O2, and 0.5 MPa of Ar gas content. The renovated LiCoO2 exhibited good electrochemical properties, the first charge and discharge capacity of 132.1mAh•g − 1 and 131.0mAh•g − 1, and the first cycle efficiency arrived at 99.16%. Additionally, an environmentally friendly and efficient route for the recycling of spent lithium-ion batteries was developed.

The antioxidant index and chemometric analysis of tannin, flavonoid, and total phenolic extracted from medicinal plant foods with the solvents of different polarities

This study aimed to evaluate the effect of four solvents (water, methanol, ethyl acetate, and n‐hexane) on the extraction of total phenolic content (TPC), tannin, flavonoid, ferric reducing power (FRAP), and radical scavenging activity from Centella asiatica, Musa acuminata, Peperomia pellucida, and Psophocarpus tetragonolobus. The extraction of TPC, tannin, flavonoid, and antioxidant activity varied significantly according to solvent polarity and plant species. The strong linear correlation found between solvent polarity index and TPC, tannin, FRAP as well as radical scavenging activity indicated solvents with increasing polarity favored the extraction of phenolic antioxidants. Plant species and extraction solvents contributed to 51.7% and 21.8% of total activity variation, respectively. C. asiatica, M. acuminata flower, and P. pellucida were best extracted with 80°C distilled water for a short duration, while methanol was preferred for P. tetragonolobus. The antioxidant index could be a potential ranking tool to identify the ideal extraction solvent for medicinal plants. PRACTICAL APPLICATIONS: Considering the high commercial and health‐oriented values of natural phenolic antioxidants such as tannin and flavonoid, efficient extraction of these phytochemicals from different plant sources remains a challenging task due to their varying physicochemical characteristics and solubility. This study has addressed that the choice of solvents and types of plant species are critical extraction parameters for natural plant products. Comparison of tannin and flavonoid content among the different solvent extracts could reveal the ideal solvent which maximizes the extraction of phenolic antioxidants from different medicinal plants. The finding in this study may inspire nutraceutical, pharmaceutical, and cosmetic industries to re‐evaluate their procedure in selecting the optimal extraction solvent and condition for different plant materials. The proposed antioxidant index in this study could serve as a potential tool to rank extraction solvents based on the antioxidant values extracted from different medicinal plants.

Briquette production from rice husk by using screw compaction

Most of the agricultural residues have low density resulting in increasing the cost of storage and transportation. With the reduced volume by the compacting process, density and other properties are increased while the storage and transportation space and cost can be reduced. The effects of screw characteristics on the briquette qualities were measured. The process condition for producing fuel briquettes with screw extruders can be used as renewable energy in the industry. Rice husk was collected and its moisture content was reduced around 8-12%. A screw used as feeding and compacting with a length of 45 centimeters and 19 degrees of screw tip angle. The mold temperatures were around 300-400 degrees Celsius. Three lengths of the screw were tested. While the briquette properties were analyzed, such as density durability, an expansion length, heating value, and moisture content of fuel briquettes after the compression process. The experimental results showed that the suitable compression condition for agricultural materials was in the range of 45.9 cm screw length and mold temperature in the range of 330 - 360 degrees Celsius. The briquettes had a durability of 98.67%, a density of 0.846 g/cm3, expansion ratio of 1.1853 %, the heat value of 3813 cal / g, moisture content after compression of 1.9% w.b. and capacity of 112.8 kg/hr. Increasing the screw length improved the performance of compression, continuous working, and briquette fuel quality. Reducing the screw length required a higher mold temperature, leading to the failure of continuous working, defective machines due to extra burden and deteriorating quality of fuel briquettes.

Parameter-free model to estimate thermal conductivity in nanostructured materials

Achieving low thermal conductivity and good electrical properties is a crucial condition for thermal energy harvesting materials. Nanostructuring offers a very powerful tool to address both requirements: in nanostructured materials, boundaries preferentially scatter phonons compared to electrons. The computational screening for low-thermal-conductivity nanostructures is typically limited to materials with simple crystal structures, such as silicon, because of the complexity arising from modeling branch- and wave-vector-dependent nanoscale heat transport. The phonon mean-free-path (MFP) dependent Boltzmann transport equation (MFP-BTE) approach is a model that overcomes this limitation. To illustrate this, we analyze thermal transport in 75 nanoporous half-Heusler compounds for different pore sizes. Our calculations demonstrate that, in most cases, the optimization of thermal transport in nanostructures should take into account both bulk thermal properties and geometry-dependent size effects, two aspects that are typically engineered separately. To enable efficient calculations within this paradigm we derive a model, based on the ``gray'' formulation of the BTE, that can decouple the influence of the geometry and the material on the effective thermal conductivity with relatively little loss in accuracy compared to the MFP-BTE. Our study motivates the need for a holistic approach to engineering thermal transport and provides a method for high-throughput low-thermal conductivity materials discovery.

Linear and Non-Linear Stress Analysis for the Prediction of Fracture Toughness for Brittle and Ductile Material using ASTM E399 and ASTM E1290 By ANSYS Program package

Prediction of fracture toughness value of most the metallic materials is a very important issue to be consider in designing of engineering structural components like pipes, flow tanks and pressure vessel where it can be used in the evaluation of critical crack length that is consider very important factor in non-destructive testing because during inspections of these components, the critical crack length is being compared with the minimum allowable flow size. Fracture toughness value can be predicted by using two different types of experimental tests such as ASTM-E399 (which is used to predict fracture toughness under plane strain condition for brittle materials which undergo to small plastic deformation) and ASTM-E1290 (which is used to predict fracture toughness for ductile materials which undergo to large plastic deformation). These experimental tests utilize specimens such as compact tension specimen CT and three-point bend specimen SENB which must be pre-cracked. However, manufacturing of pre-cracked in metallic structural components before testing is expensive and time-consuming process, thus in the current study, fracture toughness will be predicted by using economized method in both time and cost that is the finite elements method by using ANSYS PROGRAM Where, a three-dimensional model has been designed by using two different types of elements (plane-82) and (solid-95).Firstly, two-dimensional model mesh will be idealized by using element type (plane-82) due to ANSYSY PROGRAM can pick–up singularity for two dimensional model only, but in order to obtain more accurate results, a three dimensional model will be designed by utilizing Sweep Model with restriction with ANSYSY abilities in the treatment of fracture mechanics problems for three dimensional model analysis where the element length must be ranging from 1to4 in all directions. In elastic region, the fracture toughness is been predicted directly from ANSAYS PROGRAM using the specification in ASTM-E-399 for compact tension specimen for practical design problems. But in elastic-plastic region, the fracture toughness is been predicted by using the crack tip opening displacement model (CTOD-Model) using the specification in ASTM-E-1290 for three-point bend specimen for practical design problem. The critical value for crack tip opening displacement will be calculated after extracting load-displacement data from ANSAYS PROGRAM then using these data in (CTOD-Model) which is separated into two components, elastic and plastic, the elastic component has been estimated using Dug Dual-Model, while the plastic component will be estimated using Plastic Hinge-Model. However, the fracture toughness value that has been predicted by finite element method from non –linear elastic analyses and from non –linear elastic-plastic analyses gives excellent results which are very close to the experimental results with error ratio ranging between (10% to 14%).

Acceleration of turmeric drying using convection and microwave‐assisted drying technique: An optimization approach

The aim of this study was to optimize the drying process of turmeric using convection drying followed by microwave drying to accelerate the drying time. Convection time (0–30 min) and microwave time (20–60 min) were the two investigation factors. The obtained dried turmeric was pulverized. Water, volatile oil, and curcuminoid contents were determined. Weight loss after drying was also investigated. Results showed that increasing the convection time and microwave time increased weight loss and decreased water content. Microwave time had a significant effect on water, volatile oil, and curcuminoid contents, while convection time did not. The highest content of volatile oil and curcuminoids, and the lowest content of water were found when microwave drying was carried out for approximately one hour without convection drying. In summary, the optimization of the drying process could accelerate the drying time and turmeric that met the standards of Thai Herbal Pharmacopoeia. Practical applications The optimization data could be used as a guide for the selection of drying condition for turmeric raw materials to meet the standards of the Thai Herbal Pharmacopoeia.

Design of laser parameters for selectively laser melted maraging steel based on deposited energy density

In this study, the effects of laser power and scan speed on the relative density, melt pool depth, and Vickers hardness of selectively laser melted (SLM) maraging steel were systematically investigated. The change in these structural parameters and hardness could not always be clarified by the volumetric energy density, which is widely used in the SLM processes. The deposited energy density, wherein the thermal diffusion length is used as a heat-distributed depth, can express the change in these structural parameters and the hardness with one curve. To clarify the effect of the laser parameters, the deposited energy should be used instead of the volumetric energy density. Thus, this study provides a new insight on the selection of the laser condition for SLM-fabricated materials.

Yield condition and dissipation function for porous materials

A yield condition was proposed in this paper and associated dissipation function was derived via singular Legendre transformation. As a result, an explicit form of the dissipation function was obtained, which can be used for dual formulation of perfect plasticity model. The three-parameter yield condition enables continuous transition from the Drucker-Prager to Huber-Mises yield conditions by appropriate selection of free parameters. Calibration of the free parameters based on typical experimental tests was discussed. Based on the proposed yield function, a constitutive model of elastic-plastic material was given. The model can be used for modelling porous metals and other frictional materials.

Ultrafast bone-like apatite formation on bioactive tricalcium silicate cement using mussel-inspired polydopamine

The growing bone-like apatite layer at the tissue-implant interface is the essential condition for materials to bond robustly to surrounding bone and may provide a favorable environment for living bone formation. Inspired by versatility of mussel adhesive proteins, we developed an ultrafast and accessible route to accelerate effectively the formation of amorphous calcium phosphate (ACP), the precursor phase of bone-like apatite, on the surface of polydopamine (PDA)-coated tricalcium silicate (TCS) within 5 min in simulated body fluid (SBF). The key of the method lies in successful preparation of PDA coating on the surface of hydrated TCS by simple dip-coating of hydrated TCS in an aqueous solution of dopamine. A strong adsorption between PDA coating and surface of hydrated TCS could be formed via bidentate hydrogen and electrostatic bonds. After 7 d of soaking in SBF, the bone-like apatite layer on the surface of PDA-coated TCS disk, about 91.1 µm in height was thicker than that on the surface of pristine TCS disk, determining about 49.5 µm. The results indicate that PDA coating can facilitate the kinetic deposition of bone-like apatite on its surface. The abundant Ca2+ ions and the lower interface energy of ACP at the interface between ACP and surfaces of PDA-coated TCS disks are responsible for the ultrafast precipitation of ACP and formation of bone-like apatite layer which is carbonated hydroxyapatite (HA) confirmed by different analytical tools. The route can open avenues for development of PDA-coated TCS biomaterials for hard tissue repair and substitution.

Modeling of water transport in highly saturated concrete with wet surface during freeze/thaw

Wet frost exposure is a usual environmental condition for cement-based materials (CBM) during winter and the most common way of frost testing in the lab. In this study, the temperature gradient, pressure gradient, and the liquid flow under wet frost exposure are modeled for highly saturated CBM with different amount of entrained air. It is found that the water uptake happens at the melting stage, and for non-air-entrained CBM, the hydraulic pumping effect is dominant and will suck the water from wet surface. While for air-entrained CBM, the cryosuction pressure is the main driving force of the inward flow. The results are compared with experimental data from rapid freeze/thaw testing of various types of concrete in water, showing a satisfactory agreement. Sensitivity analysis also indicates that the hydraulic induced flow depends on the amount of entrained air, while the cryosuction induced flow mainly relies on the permeability and temperature gradient.

Unfolding of a Single Polymer Chain from the Single Crystal by Air-Phase Single-Molecule Force Spectroscopy: Toward Better Force Precision and More Accurate Description of Molecular Behaviors

Understanding the mechanisms of the mechanical deformation of lamellar crystals at the molecular level is of prime importance to rational design of advanced crystalline polymer materials. Single-molecule force spectroscopy (SMFS) can directly characterize molecular behavior and kinetic parameters that are masked in ensemble measurements. However, current SMFS approach cannot sufficiently manipulate a single molecule in air, which is the real working condition for most crystalline polymer materials. Here, we establish an air-phase atomic force microscopy (AFM)-based SMFS method that allows the unfolding of a single helical poly(ethylene oxide) (PEO) chain from the single crystal in air. Our results show that the mechanostability of PEO stem and unfolding potential are significantly enhanced in air compared with the case in liquid. The air-phase SMFS method can achieve a much better force precision of 4 pN even at rapid stretching velocity of ∼100 μm/s. Moreover, some intermediate states (e.g., the movement...

Numerical analysis of a thermal contact problem with adhesion

In this paper, we study a class of dynamic thermal problems involving a frictional normal compliance adhesive contact model and a non-clamped condition for visco-elastic materials. The variational formulation of the problem leads to a general system defined by a second-order quasi-variational evolution inequality on the displacement field coupled with the two first-order evolution equations describing the evolution of the temperature and adhesion. We establish an existence and uniqueness result of the solution on displacement, temperature and adhesion. Then we provide a fully discrete numerical scheme of approximation and derive an error estimate. Finally, various numerical computations are included.

Ultrathin Film Broadband Terahertz Antireflection Coating Based on Impedance Matching Method

Broadband antireflection coatings for terahertz (THz) components are extremely important in the application of THz technology. We present an in-depth materials study on the broadband antireflection design based on the concept of impedance matching. Several selected conductive materials are tested and compared. They can all be used as THz broadband antireflection coatings regardless of their nature of conductivity. We provide a facile method to approximately predict the impedance matching condition for various conductive materials based on their dc real conductivity. The theoretical predications are in good agreement with experimental results and published data. Doped metal oxides or polymers are recommended as good candidates for fabricating antireflection coating in THz range. The thickness-independent dc real conductivity enables better control on individual tuning parameter—film thickness. Given a substrate, THz transmission in antireflection coating has a theoretical upper limit which is further reduced with non-negligible imaginary conductivity.

Numerical and experimental analysis of a RVE condition for heterogeneous materials using BEM and thermal images

espanolEste trabajo se enfoca en el estudio numerico y experimental de los efectos de la conductividad termica en materiales heterogeneos. El analisis numerico se basa en la formulacion de Metodo de los Elementos de Contorno (MEC) basada en la tecnica de subregiones con el fin de simular un dominio bidimensional con inclusiones de material distribuidas aleatoriamente. Las condiciones de contorno fueron seleccionadas adecuadamente con el fin de obtener condiciones de conductividad termica unidireccional. La Teoria de los Campos Medios (TCM) es aplicada para determinar el elemento de volumen representativo (EVR) para los casos estudiados. Finalmente, el coeficiente de conductividad termica efectivo es obtenido a partir del EVR. Para la verificacion de los resultados numericos obtenidos es propuesto un procedimiento experimental basado en imagenes termicas. El montaje experimental replica la condicion de flujo de calor unidireccional en una placa de acero. La conductividad termica efectiva experimental es obtenida a partir del analisis de las imagenes termicas del campo de temperatura resultante en la superficie de la placa las cuales fueron tomadas con una camara infrarroja. La comparacion entre los resultados numericos y experimentales resulto en una diferencia de 3% entre los dos resultados, apuntando el buen desempeno de la metodologia propuesta. EnglishThis work focuses on the numerical and experimental study of the effective thermal conductivity in materials with heterogeneous composition. The numerical analysis relies in the Boundary Element method (BEM) formulation assisted by the sub-regions technique to simulate a two-dimensional square domain, with randomly distributed material inclusions. The boundary conditions are set to achieve a unidirectional heat flux condition. The Average Field Theory (AFT) is applied to determinate the representative volume element (RVE) condition for the studied cases. Finally, the effective heat conduction coefficient is obtained from the defined RVE’s. To verify the obtained numerical results, it is proposed an experimental procedure based on thermal images. The experimental assembly replicates the unidirectional heat flux condition over a steel plate. The experimental effective thermal conductivity is obtained from the analysis of the resultant temperature field on the surface of the plate taken by an infrared camera. The comparison between the numerical and experimental results showed a 3% difference between both results, pointing out for the successfulness of the proposed methodology.