Optimal Parameters Research Articles

Mitigation of Mycotoxin Content by a Single-Screw Extruder in Triticale (x Triticosecale Wittmack)

The aim of this study was to investigate the effects of extrusion processing parameters—moisture content (M = 20 and 24%), feeding rate (FR = 20 and 25 kg/h), and screw speed (SS = 300, 390 and 480 RPM), on the content of deoxynivalenol (DON), 15-Acetyl Deoxynivalenol (15-AcDON), 3-Acetyl Deoxynivalenol (3-AcDON), HT-2 Toxin (HT-2), tentoxin (TEN) and alternariol monomethyl ether (AME), using a pilot single-screw extruder in whole-grain triticale flour. The temperature at the end plate of the extruder ranged between 97.6 and 141 °C, the absolute pressure was from 0.10 to 0.42 MPa, the mean retention time of material in the barrel was between 16 and 35 s, and the specific energy consumption was from 91.5 to 186.6 Wh/kg. According to the standard score, the optimum parameters for the reduction of the content of analysed mycotoxins were M = 24 g/100 g, FR = 25 kg/h, SS = 480 RPM, with a reduction of 3.80, 60.7, 61.5, 86.5, 47.7, and 55.9% for DON, 3-AcDON, 15-AcDON, HT-2, TEN, and AME, respectively. Under these conditions, the bulk density, pellet hardness, water absorption index, and water solubility index of the pellet were 0.352 g/mL, 13.7 kg, 8.96 g/g, and 14.9 g/100 g, respectively.

Catalytic epoxidation of waste palm kernel oil using in situ performic acid formation

AbstractThe use of renewable resources in the epoxidation process can reduce the dependence on non‐renewable petroleum resources and contribute to a more environmentally friendly chemical industry. This study aims to investigate the epoxidation of waste palm kernel oil as a renewable feedstock. The synthesis of epoxidized waste palm kernel oil was conducted by reacting waste palm kernel oil, formic acid, and hydrogen peroxide in a one‐pot system. Currently, there is no reported literature on the simultaneous application of a catalyst for the epoxidation of waste palm kernel oil derived from industrial waste. The optimum process parameters were determined, including hydrogen peroxide to waste palm kernel oil molar ratio (1.5:1), formic acid to waste palm kernel oil molar ratio (0.5:1), and stirring speed (300 rpm). The optimum relative conversion to oxirane of epoxidized waste palm kernel oil was 88%. A mathematical model was developed using numerical integration based on the fourth‐order Runge–Kutta method as follows: = 0.894 mol·L−1·min−1, = 7.420 mol·L−1·min−1, and = 0.086 mol·L−1·min−1. Based on the findings of the kinetic study, the kinetic model was validated due to its minimal simulation error.

Optimization of laser process parameters and improved corrosion behaviour of LZ/YSZ thermal barrier coating

Abstract Laser processing the surfaces of plasma-sprayed thermal barrier coatings is one of the methods used to improve the corrosion resistance of the coatings. However, laser glazing alone is not sufficient to fully protect coatings from corrosion. In this study, optimum laser surface modification parameters were determined for plasma-sprayed LZ/YSZ double-layer thermal barrier coatings. The coating surface, whose entire surface was scanned with optimum parameters, was modified with nano YSZ using the electrophoretic deposition technique. Thus, the network cracks formed during laser glazing were filled with nano YSZ. The coating modified by laser and electrophoretic deposition processes was subjected to corrosion tests. As a result of the characterizations, it was determined that the optimum laser surface modification parameters for LZ/YSZ thermal barrier coatings were 200 mm laser distance, 120 scan speed, and 28w laser power. With these parameters, discontinuities on the as-sprayed coating surface were eliminated. A dense layer was successfully created on the LZ layer. As a result of the corrosion tests, it was determined that modifying the laser-glazed surface with nano YSZ reduced the penetration depth of corrosive contaminants. Thus, the glassy melt and hot corrosion resistance of LZ/YSZ thermal barrier coatings was increased.

"Theory of Pore Conflation" and "Shubhjyot's equation" in the treatment of Brilliant green dye-contaminated water using Jamun leaves biochar

This study investigates the adsorption of Brilliant Green (BG) dye onto biochar derived from Syzygium cumini (Jamun) leaves (JLB). Biochar was produced via pyrolysis at 800 °C and examined employing various methods, including Scanning electron microscopy (SEM–EDX), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) analysis, Raman spectroscopy, Zeta potential and X-ray photoelectron spectroscopy (XPS). The optimum parameters for BG dye adsorption, determined by batch adsorption studies, were a temperature of 80 °C, an initial dye concentration of 500 mg L−1, a contact period of 30 min, and an agitation speed of 400 RPM. The maximum adsorption capacity of JLB for BG was 243.90 mg g−1. It was found that the adsorption process adhered to the Freundlich isotherm model and pseudo-second-order kinetics, revealing heterogeneous adsorption with chemisorption. A novel "Theory of Pore Conflation" was proposed to explain enhanced adsorption at higher temperatures, supported by SEM and FTIR analyses. Additionally, a new equation termed "Shubhjyot's equation" was introduced to account for time dependency in adsorption capacity calculations. The thermodynamic analysis demonstrated that the process is endothermic and spontaneous. Isopropanol was the most effective organic solvent for desorption studies, demonstrating biochar regeneration potential for up to five cycles. Phytotoxicity and cyto-genotoxicity assessments demonstrated the environmental safety of JLB compared to BG dye. The use of JLB production offers a way to repurpose agricultural waste, contributing to circular economy principles. This extensive study demonstrates JLB's promise as an effective, economical, and environmentally safe adsorbent for wastewater treatment that eliminates textile dyes.Graphical

Synergistic enhancement of the dynamic impact damage resistance and energy absorption of ultra‐high molecular weight polyethylene fiber reinforced composites with multiple plasma modification

AbstractThe study reveals the dynamic impact damage resistance and energy absorption of oxygen/argon/nitrogen multiple plasma modified ultra‐high molecular weight polyethylene (UHMWPE) fiber reinforced composites. The interface bonding properties and impact resistance of the composite were studied by microsphere debonding test, low‐velocity and high‐velocity impact test. The modified parameters are optimized based on quadratic polynomial equation. The impact resistance of the composite was evaluated from the aspects of ballistic limit velocity, failure mode and energy dissipation mechanism. The results showed that compared with untreated composites, the depth of dents and damage area of multiple plasma modified composites were reduced by 43.53% and 11.73%, respectively. The energy absorption and limit velocity of high‐velocity impact were increased by 14.64% and 25.58%, respectively. The modified composites formed an energy dissipation mechanism dominated by fiber breakage. The impact damage resistance and energy absorption of UHMWPE fiber reinforced composites were enhanced with multiple plasma modification.Highlights Multiple plasma modification enhance synergistic energy absorption of composites. The optimum treatment parameters of composites plasma modification were analyzed. Interface bonding properties were evaluated from microscopic perspective.

Ni-Co doped TiO2 catalyst for efficient photocatalytic degradation of Malachite Green under UV and direct sunlight.

In the present study, combustion-synthesized TiO2 nanoparticles were wet impregnated with Ni, Co, and Ni-Co, respectively. The photocatalytic performance of synthesized catalysts was evaluated against Malachite Green dye. The synthesized materials were characterized for crystallite size, surface morphology, elemental composition, and band gap using X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, and ultra-violet diffused reflectance spectroscopy, respectively. The optimum parameters for maximum degradation were found by examining the effects of catalyst loading, initialdye concentration, and light intensity. A comparative analysis of Ni-doped, Co-doped, and Ni-Co-doped TiO2 photocatalysts wasconducted. The results indicate superior photocatalytic activity of Ni-Co doped TiO2 among the catalysts investigated under UV light. The degradation kinetics was studied, and the underlying degradation mechanism was proposed with the help of LC-MS analysis. Furthermore, a comparative study on the degradation under solar radiation using Ni-Co/TiO2 was conducted.

Application of response surface methodology (RSM) for experimental optimization in biogenic silica extraction from rice husk and straw ash

This work aimed to extract silica from combination of rice husk (RH and Rice straw (RS) by optimizing the ash digesting process parameters with the aid of response surface methodology (RSM). The effects of three independent ash digestion process factors like sodium hydroxide concentration (1–3 M), temperature (60–120 °C) and time (1–3 h), for silica production from the mixture of rice husk (RH) and rice straw (RS) were studied. A quadratic model was used to correlate the interaction effects of the independent variables for maximum silica production at the optimum process parameters by employing central composite design (CCD) with RSM. The work indicates that the temperature is the most significant parameter among the model terms, followed by NaOH concentration, then time for digestion of ash for silica production. It may be because of the larger F-value for temperature, which influences to high extent of ash digestion for silica production. The proximate analysis discovered that RH/RS possessed compositions of high ash, volatile matter and fixed carbon content whereas low moisture content, i.e., 20.5 ± 0.46, 67.1 ± 0.78, 15.8 ± 0.35 and, 6.6 ± 0.37 wt.%, correspondingly. The characterization of RH/RS and silica were performed by employing thermogravimetric (TG) and differential thermal (DT), Fourier transforms infrared spectroscopy (FTIR), X-ray fluorescence spectroscopy (XRF) and Brunner–Emmet–Teller (BET) for confirmation of the silica production. Hence, this current study concludes that silica materials obtained from RH/RS (with purity > 97.35 wt.%) may be new materials in the Si–C–O system that may be used in construction, ceramics and silica gel that helps to absorb moisture.

A new SLM-manufactured Al[sbnd]Si alloy with excellent room and elevated-temperature mechanical properties

The synergistic strengthening of multiple phases has long been an effective method of enhancing conventional metallic structural materials. However, the assembly of solute atoms with high solubility and low diffusion rate into highly stable and high-volume fraction nano-precipitates using the selective laser melting (SLM) technique is challenging. In this study, a new Al-9.0Si-2.8Fe-2.1Mn-1.1Ni (in wt%) alloy was fabricated using the SLM. The melt pool structure of the alloy exhibits equiaxed grain characteristics under optimum parameters, with large volume fractions of in-situ precipitated IMC-Al15(Fe,Mn,Ni)3Si2 and Si phases within the grains. The alloy demonstrates commendable tensile properties at room temperature (YS 373 ± 8 MPa, UTS 602 ± 12 MPa, El 4.2 ± 0.5 %) and retains excellent strength and ductility as well as creep resistance at elevated temperatures of 400 °C (YS 92 ± 3 MPa, UTS 100 ± 5 MPa, El 24 ± 0.7 %, steady-state creep rate ~ 10−5 s−1 under 60 MPa). Lamellar nano-Si phases can induce strain delocalization effects and grain boundary relaxation through partial dislocation twinning behavior, thereby coordinating high-temperature deformation. Under large deformations and prolonged creep processes, the transmission of external loads and the evolution of defects (The edge dislocation at interfaces, the stacking faults and deformation twins within the Si phase) effectively transfer stress to low-load-bearing regions, promoting the delocalization of deformation. The abundant second phases within the alloy (IMC and Si phases) hinder dislocation movement and promote dislocation multiplication, maintaining ultra-high deformation resistance and low steady-state creep rate. Due to the absence of heat treatment and the addition of expensive elements, the alloy has wide industrial application potential.

Selection of optimum intensity measure parameters for seismic fragility analysis of typical Roman aqueduct

Selection of optimum intensity measure parameters for seismic fragility analysis of typical Roman aqueduct

Quality by Design and Characterization of Nimodipine Novel Carriers for the Treatment of Hypertension: Assessment of the Pharmacokinetic Profile

Background: Nimodipine is a highly lipophilic anti-hypertensive drug having 13% oral bioavailability (log P 3.41). Nimodipine is a prominent calcium channel blocker that must be given intravenously for an extended period of time (1-2 weeks) in order to treat cerebral vasospasm. It might be possible to substitute a sustained-release biodegradable formulation for the ongoing intravenous infusion used in this traditional therapy. Objectives: The primary goal of this study was to formulate and evaluate the potentiality of ethosomes to deliver nimodipine, a potent water-insoluble anti-hypertensive drug, through the deeper layers of the skin. The greatest challenge for drug formulation is its poor oral bioavailability and solubility. Methods: Nimodipine-loaded ethosomal gel was developed for transdermal drug delivery to increase solubility and skin penetration and to promote oral bioavailability. Central composite design employing a thin-film hydration method was used to prepare and optimize ethosomes. A better dispersion medium for nimodipine's preparation in ethosomes was selected based on the effect. The design consisted of independent variables as lipid (X1), ethanol (X2), and sonication time (X3). Concentrations were manipulated to examine the effects on three responses, namely the %entrapment efficiency (Y1), vesicle size (Y2), and %cumulative drug release (Y3). Surface morphology and other in vitro tests were used to identify ethosomes containing nimodipine. The preparation of ethosomal gel formulations began with incorporating a single ethosomal formulation (F4) into various concentrations of gelling agents. These studies performed physicochemical characterization, compatibility testing, and in vitro drug release tests on ethosomal gels. In vivo studies involving hypertensive rats were conducted after skin permeation, and ex vivo studies were performed. In order to assess the drug's permeability and deposition, we employed the abdomen skin of rats. Results: The optimal process parameters resulted in ethosomes with 89.9 ± 0.19 percent entrapment efficiency, a vesicle size of 102.37 ± 5.84 nm, and a cumulative drug release of 98.3 ± 0.13%. pH and drug content measurements were consistent with the homogeneous ethosomal gels. Viscosity was found to increase with the spreadability. The ethosomal gel formulation (G2) met the regulatory standards regarding appearance, spreadability, viscosity, and in vitro release studies. Compared to pure nimodipine, ethosomal suspension (F4) and ethosomal gel (G2) formulations had higher ex vivo permeation, steady-state flux, and drug retention. Rats' mean arterial pressure (146.11 ± 0.84 mmHg) was significantly lower (p < 0.01) after after two hours of the experiment than it had been (p < 0.001) (98.88 ± 0.63 mmHg) after six hours. Conclusion: To summarize, ethosomal gels have been found to be lipid carriers that enhance skin permeation and extend the anti-hypertensive effect of nimodipine. Compared to plain gel, ex vivo drug permeation through rat abdominal skin in ethosomal gel was enhanced. Gel-based ethosomal transdermal drug delivery formulations of nimodipine can be used to achieve a faster rate and extend the duration of drug delivery by more than 24 hours.

The accurate determination of Perfluorooctane sulfonic acid (PFOS) removal efficiency by integrated-sonochemical system.

Perfluorooctanesulfonic acid (PFOS) is one of the most investigated Per- and polyfluoroalkyl substances (PFAS) for being the strongest compound to eliminate and having adverse health concerns. In this work, we have conducted the sonochemical treatment of PFOS simulated water under high (500kHz) and low (22kHz) frequencies while monitoring the operational parameters via an integrated sonochemical system. The integrated advanced sonochemical system includes software to monitor treatment power, solution temperature and frequency while allowing distinctive control of the reaction conditions. Considering the lack of calorimetric measurements in earlier studies and the difficulty in achieving comparative outcomes, precise calorimetric measurements and determination of electrical energy per order (EEO) were performed in this study. The complete PFOS removal was achieved under 500kHz frequency with optimum parameters including initial pollutant concentration (5mg/L), ultrasound power density (400W/L) and solution temperature (25°C) within 180min of treatment. The removal and mineralization extents (defluorination) were determined by ultra-high performance liquid chromatography-mass spectrometry (UPLC-MS/MS) and ion-chromatography (IC) analysis. Under optimum conditions, 100% removal and 99% mineralization were achieved. The rate constant (k) ranged from 0.011 to 0.031 min-1 (first-order reaction), which increased with the increase in the power density. While the solution temperature did not significantly affect the PFOS removal efficiency, the initial concentration was found to have a prominent effect on the reaction rate constant. However, experiments at low frequency (22kHz) showed negligible removal efficiency. The specific energy requirement for reaching 90% removal while considering the power consumed by the ultrasonic system from the main electrical source was determined to be 700 kWh/m3, which is much lower than other reported work under similar conditions. This work will be useful for both laboratory and industrial upscaling while acting as a benchmark reference to follow.

Effective Data Classification using Interval Neutrosophic Covering Rough Sets based on Neighborhoods for FinTech Applications

Neutrosophic set (NS) is particularly appropriate in applications where data is incomplete, unclear, or inconsistent, which offers an effectual means for analyzing and exhibiting complex mechanisms. An NS is a mathematical technique to manage uncertainty, indeterminacy, and imprecision. It enlarges classical sets, IF sets, and fuzzy sets by presenting three degrees such as indeterminacy (I), false (F), and truth (T). Financial technology (Fintech) plays an essential part in advancing modern society, technology, economies, and various fields. Financial crisis prediction (FCP) plays a crucial role in shaping economic outcomes. Past research has predominantly focused on using deep learning (DL), machine learning (ML), and statistical methods to forecast the financial stability of business. In this manuscript, we focus on the development of Effective Data Classification using Interval Neutrosophic Covering Rough Sets based on Neighborhoods and Multi-Strategy Improved Butterfly Optimization (EDCINCRS-MSIBO) Algorithm for FinTech Applications. It contains distinct kinds of stages such as data normalization, feature selection, classification, and parameter tuning. In the EDCINCRS-MSIBO technique, a min-max normalization-based data pre-processing model to scale the raw data into a uniform format. For feature subset selection, the whale optimizer algorithm (WOA) is employed to reduce the dimensionality and improve model efficiency by selecting the most relevant features. In addition, the EDCINCRS-MSIBO technique takes place interval neutrosophic covering rough sets (INCRS) classifier is utilized for detection and classification of a financial crisis. Finally, a multi-strategy improved butterfly optimization algorithm (MSIBOA) is exploited for the optimum parameter adjustment of the INCRS model. To confirm the better predictive solution of the EDCINCRS-MSIBO model, a wide range of simulations are executed on the two benchmark databases. The comparative result analysis displays the encouraging outcomes of the EDCINCRS-MSIBO method on the existing techniques

A comparative study of double-pass recycle type hybrid photovoltaic thermal designs

ABSTRACT Photovoltaic (PV) panels play a crucial role in solar systems but are susceptible to efficiency losses caused by rising surface temperatures. This research explores four distinct recycle-type double-pass hybrid PV/T designs, employing steady-state models to cool the PV panels. The first and second designs mount the PV panel on the absorber plate, while the third and fourth designs position it directly over the absorber plate without a glass cover, allowing the sun’s radiation to fall directly on the PV module. The study investigates the significant impacts of varying values of ṁ (0.03–0.15 kg/sec), G (0.3–1.8), D (1.0–6.0), I (300–1000 W/m2), and P (0.4–0.95) on thermal and electrical efficiency, as well as net electrical power generation, taking into account pressure loss during the flow. Through the analytical study, Design-IV demonstrates the highest net electrical power, estimated at 54.82W, which is 6.27% higher than Design-III, achieved at a recycling ratio, mass flow rate, depth ratio, and packing factor of 0.9, 0.15 kg/s, 3, and 0.5, respectively. Additionally, the input parameters are optimized using the Response Surface Methodology (RSM) technique. The analysis of variance (ANOVA) reveals a significant coefficient (R2) value approaching unity, indicating a strong fit of the response model to the analyzed data. By considering both single and multi-objective optimization scenarios, the study identifies optimal parameters for each PV/T design through the interaction of operational parameters. This research contributes to enhancing the efficiency and performance of double-pass recycle-type hybrid PV/T systems, enabling sustainable and effective utilization of solar energy resources.

Simulation of the enclosing rock displacements around the development mine workings

Purpose is to develop and substantiate a mathematical model for forecasting of rock displacements around the development mine workings and optimization of techniques for their reinforcement. Methods. A comprehensive approach has been applied including numerical simulation; theoretical analysis; and experiments. Special attention has been paid to rock displacements based upon stress-strain state of the rock mass. The developed KMS-Ш software was used for the calculation helping model displacements and analyze the obtained data. Findings. Recommendations have been proposed to decrease a rock dilatancy coefficient achieved through correction of support parameters; mine working geometry; and control of rock deformation rate. It has been demonstrated that rock bolting use lowers significantly the intensity of the displacements. It has been identified that a decline in rock strength results in the increased failure zones; at the same time, the improved plastic properties minimize elastic energy accumulation reducing the displacement probability of the opposite crack surfaces. Originality. An algorithm has been developed forecasting displacements of the mine working peripheries taking into consideration the mining, geological, and engineering factors. A mathematical model has been represented to identify both elastic and non-elastic deformations in a border zone. The dependencies between border rock mass displacements, mine working depth, and rock strength have been defined. Practical implications. Determination of optimum parameters of rock strengthening helps minimize failure zones; better stability of mine workings; and reduce the possibility of dangerous geomechanical phenomena. Use of the proposed model makes it possible to improve mining efficiency owing to more accurate forecasting of displacements.

Optimization of Operational Parameters of Power Sprayer for Spraying in Mango Plantation

Portable horizontal triplex pump (HTP) power sprayer is dominant in Konkan region especially for mango orchard spraying. A field experiment was carried out to optimize the performance of power sprayer in mango orchard. The selected mango orchard had 4.5 - 5.0 m height trees planted at 10 × 10 m spacing. Water sensitive papers of 44 × 44 mm size were stapled on up and down sides of tree leaves at different canopy positions to catch the spray deposition samples. The selected power sprayer was equipped with horizontal triplex plunger pump having power 3 kW and speed 1000 rpm. The experiment was conducted by varying the suction pressure from 980 to 1961 kPa, nozzle-to-target distance from 0.50 to 0.60 m, travel speed in range of 0.30 to 0.60 m s-1. The two nozzle types, viz., hollow and solid cone nozzle were used in the experiment. The statistical optimization was carried out using response surface methodology (RSM) with Box Behnken, randomized subtype design with total 34 experiments. The optimum parameters viz., pressure, nozzle distance and travel speed were 1471 kPa, 0.55 m and 0.45 m s-1, respectively for power sprayer with hollow cone type nozzle. At these optimized levels, the dependent variables viz., droplet size, droplet density, uniformity coefficient and spray deposition were observed as 291.4 µm, 120.12 droplets cm-2, 1.78 and 0.64 µl cm-2, respectively. These optimized parameters resulted in improved pesticide spraying efficacy with better coverage and improved safety during spraying operation in the mango orchard.

Optimization of Green Extraction Techniques for Polyphenolics in Pinus brutia Bark Extract and Steam Gasification of the Remaining Fraction to Obtain Hydrogen-Rich Syngas and Activated Carbon.

Utilization of renewable resources has become imperative, and considerable efforts have been devoted to tackling diverse global sustainability challenges, which contribute to the circular economy. The focus of this work was to optimize the extraction of polyphenolic compounds in Pinus brutia bark using microwave-assisted (MAE) and ultrasonically assisted (UAE) extractions and evaluate the biological efficacies of the extracts. Additionally, the residue of the extracted pine bark was subjected to steam gasification to produce hydrogen-rich syngas and activated carbon. The optimum process parameters for MAE were determined as 70 °C, 10 min, and 900 W, and 987.32 mg gallic acid equivalent (GAE), 23.7 mg quercetin/g extract, and 86.2% antioxidant activity were obtained. The optimum process parameters for UAE were determined as 70 °C, 20 min, and 50% power, and 811.84 mg gallic acid equivalent (GAE), 30.1 mg quercetin/g extract, and 90.8% antioxidant efficiency were obtained. The extracts obtained under optimized conditions were assessed for the bioactive phenolic compounds taxifolin, (-)-catechin, (-)-epicatechin, and (-)-epicatechin gallate by ultra performance liquid chromatography (UPLC). Especially in MAE (ethanol), taxifolin content was notable (34.0 mg/g extract), followed by UAE (ethanol) (23.5 mg/g extract). Compared to MAE (ethanol) and UAE (ethanol) with regards to catechin content, 1.05 mg/g extract and 0.81 mg/g extract were obtained, respectively. Catalytic and noncatalytic steam gasification of pine bark residue yielded 57.3 and 60.8 mol % H2, respectively. In addition, excellent tar reduction was achieved through utilizing a 10% boron-modified CaO alkali catalyst, and the obtained activated carbon exhibited 1358.32 m2/g Brunauer-Emmett-Teller (BET) surface area and 1.05 cm3/g total pore volume, which has potential use as an adsorbent for removing heavy metals and electrode material for supercapacitor application.

Modeling Using Box Behnken Design for Optimization of Biodiesel Production from Low Grade Cooking Oil

The demand to an alternative for the depletion of diesel oil, has steered to the production of biodiesel as an alternative fuel. Nowadays, there is a growing need for biodiesel, which is typically produced using a base-catalyzed transesterification reaction. Therefore, this research utilizing a low-grade cooking oil as the biodiesel feedstock and Ca/Mg/Al2O3 as a heterogenous base catalyst using wetness impregnation method. The potential catalyst was optimized using response surface methodology (RSM) by varying parameters of calcination temperature, catalyst dosage and reaction time. The optimum parameter obtained from the RSM are 800°C calcination temperature, 6wt% catalyst dosage and 1 hour reaction time. The validation is carried out using optimum parameter and it gave 48.30% of biodiesel production.

Effect of Density and Thickness of Steel–Steel Composite Metal Foam on Its Full‐Scale Torch Fire Response

Tank cars carrying hazardous materials require fire and thermal protection to prevent disasters in case of accidents. A material with a combination of improved insulating thermal properties and impact resistance within the tank car skin can mitigate the repercussions of such accidents. Steel–steel composite metal foam (S–S CMF) is a novel material with properties that is being investigated for such applications. It is made up of metallic hollow spheres closely packed together within a metallic matrix. To corroborate the effectiveness of this material for the abovementioned application, a full‐scale torch fire test based on the 49 Code of Federal Regulations, Part 179, Appendix B must be conducted on 4 × 4 ft (1219.2 × 1219.2 mm) samples, where they are required to withstand a 30 min high velocity jet fire at 1204 ± 55.6 °C, by not recording a temperature higher than 427 °C on the unexposed side of the samples within 30 min. It is necessary to determine the critical thickness of CMF for which the test would pass; however it would be costly to do this experimentally and thus, a numerical simulation must be conducted to predict the optimum parameters that can address the torch fire requirements. This study outlines the procedure adhered to in modeling the torch fire test and investigates the effect of thickness and density on the thermal response of the S–S CMF. Fire Dynamics Simulator and COMSOL Multiphysics are utilized to compare the one dimesional and three dimensional modeling of S–S CMF response to a full‐scale torch fire test. Investigation shows that the thickness and density of the material play a significant role in how it responds under torch fire conditions.

Functionally graded materials of SS316L and IN625 manufactured by direct metal deposition

Abstract Direct metal deposition (DMD) is a layer-by-layer material addition process. Partial functionally graded material (FGM) blocks of size 26 mm wide × 34 mm thick × 32 mm height were 3D printed based on Taguchi’s L9 approach using a commercial DMD machine equipped with a diode laser. The parameters selected for FGM deposition were laser power, scan velocity, and powder feed rate. The metal powders used for deposition were Stainless Steel 316L (SS316L) and Inconel 625 (IN625). The novelty is the introduction of three gradient layers for joining dissimilar materials of SS316L and IN625. ASTM E8 tensile specimens were cut from each FGM block for testing and characterization. Tensile test results revealed that the thick-layered partial FGM specimen-6 had a high ultimate tensile strength (UTS) of 532.6 MPa at the sixth set of optimum parameters. This is due to the mixed presence of coarser and fine columnar grains and equiaxed grain microstructures. Based on the analysis of variance, scan velocity had a more significant effect on UTS and powder feed rate on micro-hardness. However, a maximum micro-hardness of 202.5 HV was observed in the gradient layers of the ninth sample at the ninth set of parameters. The fractography analysis revealed the ductile failure of specimens.

Communication Link Analysis of a Low-Earth Orbit Satellites Considering Interference Sources Moving Along Various Parabola-Curved Paths.

We analyze the communication link of an LEO satellite considering interference sources moving along various parabola-curved paths. In this situation, the location of the ground station, airborne interference source paths, and the satellite's trajectory were expressed in the East-North-Up (ENU) coordinate system. The airborne interference source path is designed using a parabola equation with a directrix parallel to the satellite's trajectory to analyze the interference situation for more diverse interference source paths, rather than using a straight path. To investigate critical interference situations where the J/S ratio is maintained above -20 dB with a small deviation during the communication time, we investigate interference situations by changing the parameters of the interference source path. The genetic algorithm (GA) is used to easily find an airborne interference source path that maintains the J/S ratio above -20 dB with a small deviation. A cost function for the GA is then defined as the average difference between the J/S ratio and the reference value (-10 dB and -20 dB) during the communication time. The optimum parameters of the interference source path are determined at a minimum cost in the GA. These results demonstrate that more significant interference situations for the communication link can be easily found by using parabola-curved paths and the GA. As a result, previous studies investigated the basic tendency of the J/S ratio using straight paths. However, this study provides a database for operating an anti-jamming system based on the obtained optimized path.