Influence Of Process Parameters Research Articles

Optimization and modelling of magnesium oxide (MgO) photocatalytic degradation of binary dyes using response surface methodology

Textile industry dye effluent contains a mixture of different kinds of dyes. Many times, photocatalysis is targeted as a solution for the treatment of dye effluent from the textile industry. Many researches have been published related to the photocatalysis of single textile dyes but in the real-world scenario, effluent is a mixture of dyes. Magnesium oxide (MgO) is used as a photocatalyst to treat a mixture (binary solution) of Methylene blue (MB) and Methylene violet (MV) along with individual MB and MV dyes in this article. MgO shows remarkable photocatalytic activity at about 93 and 88% for MB and MV dye in binary solution within 135 min. Furthermore, to study the influence of process parameters, experiments are designed with the help of the central composite design (CCD), and Response surface methodology (RSM) is used to study the interactions between parameters. For this study, five parameters are selected i.e., Photocatalyst dosage, initial concentration of both dyes, time of exposure to the light source, and pH of the binary solution. The photocatalytic process is also optimized and finally optimization of process parameters is validated with an experiment. The result of the validation experiment is very close to the predicted photocatalytic activity.

Numerical simulation of the electromagnetic field in the secondary cooling zone of arc-shaped slabs

The magnetic field characteristics due to electromagnetic stirring in the secondary cooling zone of an extra-thick slab during continuous casting are numerically determined using Maxwell's equations, with particular emphasis on the distribution of magnetic induction intensity and electromagnetic force, as well as the influence of process parameters on the magnetic field. The orientation of the electromagnetic force is the same when the electromagnetic stirrers at the 30° and 60° posistions of the arc-shaped slab are powered in the same direction; otherwise, the orientation is opposite. The magnetic induction at the centre of the section of the stirrer's central axis at the 30° positio, as well as the current, frequency, and fitting formulae, are as follows: B = {0.075I(1/A)-0.3} mT and B = {-1.75f(1/Hz)+22} mT. The electromagnetic force and current fitting formula at the central point of the B-B section is F = {0.03168I2(1/A2)-03.762I(1/A)+326.7} N/m3, and the fitting formula of electromagnetic force and frequency at the centre point is divided into two segments. The first takes the form of a parabola: = {-21((f-4.3)-(1/Hz)2)+970} N/m3, and the second segment is negative linear: F = {-1.65f(1/Hz)+51.5} N/m3.

Machine learning assisted mechanical properties prediction of fine denier polyester fiber

In recent years, more and more attention has been attracted by fine denier polyester fibers in electronic information industry due to their unique structural and excellent mechanical properties. As known, the mechanical properties of fine denier polyester fibers have a close relationship with their melt-spinning process parameters, thus, it is worth further exploring the influence of process parameters on fiber mechanical properties (namely breaking strength, elongation at break and CV of breaking strength). This study aims to develop a novel prediction model based on the artificial neural network (ANN) to predict the key mechanical properties of fine denier polyester fibers. For this purpose, firstly, different specifications of fine denier polyester fibers with different mechanical properties are produced by adjusting the key melt-spinning parameters, namely spinning temperature, take-roll speed and metering pump speed. Then the experimental data is collected, analyzed and augmented with effect to be used for modeling. Next, a novel prediction model based on ANN is developed by importing the two-streams structure and two attention matrices to improve the feature abstraction for mechanical properties prediction. Lastly, different predictive performance indicators, namely root mean square error (RMSE), mean absolute percent error (MAPE) and the coefficient of determination (R2) are imported to evaluate the proposed model. For the total of three mechanical properties, the predicted results of the proposed model in terms of RMSE, MAPE and R2 are respectively 0.3499, 0.0906 and 2.9516.

Optimization of syngas production via methane bi-reforming using CeO2 promoted Cu/MnO2 catalyst

Currently, syngas plays an important role in renewable and sustainable energy production. The idea of manufacturing syngas via bi-reforming methane, which involves the combination of methane (CH4), carbon dioxide (CO2), and steam, appears very promising. As a result, the goal of this research is to improve syngas output by improving process parameters in methane bi-reforming using a 3%Ce-15%Cu/MnO2 catalyst. Optimization analysis was performed using response surface methodology (RSM). The ultrasonic impregnation (UI) method was employed to synthesize the catalysts used in this study. Following that, the catalyst was characterized using several techniques such as Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD), temperature programmed reduction (TPR), temperature programmed desorption (TPD), and temperature programmed oxidation (TPO). The findings of the characterization show that the presence of CeO2 promoters has a dual effect on the size of CuO crystallites. Firstly, it reduces the size from 19.07 nm to 13.66 nm because to the dilutive effect generated by the inclusion of CeO2. Second, the presence of CeO2 promoter accelerates the transition from CuO to Cu0 metallic phase. Furthermore, the addition of CeO2 boosts the CH4 and CO2 conversion rates by 23.65% and 24.93%, respectively. As a result, the H2 yield increases significantly when compared to the unpromoted catalyst. The study investigates the influence of process parameters, specifically the reaction temperature (700–900℃), CO2 ratio (0.2–1), and gas hourly space velocity (GHSV) (16–36 L g cat−1 hr−1), on the conversion of CH4 and CO2, as well as the H2/CO ratio. The optimization study finds that the highest conversion rates for CH4 and CO2 are 78.32% and 72.45%, respectively, when the reaction temperature is 800 °C, the CO2 ratio is 0.6, and the gas hourly space velocity (GHSV) is 26 L g cat−1 hr−1. The optimum conditions result in the highest syngas ratio of 1.77. The results of the optimization are then assessed using the mean errors. The H2/CO ratio, as well as the average errors for CH4 and CO2 conversions, are discovered to be 0.15%, 0.95%, and 0%, respectively.

Characterization of Interfacial Corrosion Behavior of Hybrid Laminate EN AW-6082 ∪ CFRP.

The corrosion behavior of a hybrid laminate consisting of laser-structured aluminum EN AW-6082 ∪ carbon fiber-reinforced polymer was investigated. Specimens were corroded in aqueous NaCl electrolyte (0.1 mol/L) over a period of up to 31 days and characterized continuously by means of scanning electron and light microscopy, supplemented by energy dispersive X-ray spectroscopy. Comparative linear sweep voltammetry was employed on the first and seventh day of the corrosion experiment. The influence of different laser morphologies and production process parameters on corrosion behavior was compared. The corrosion reaction mainly arises from the aluminum component and shows distinct differences in long-term corrosion morphology between pure EN AW-6082 and the hybrid laminate. Compared to short-term investigations, a strong influence of galvanic corrosion on the interface is assumed. No distinct influences of different laser structuring and process parameters on the corrosion behavior were detected. Weight measurements suggest a continuous loss of mass attributed to the detachment of corrosion products.

Study on Al Evaporation during AlV55 Melting and Alloy Preparation

Vacuum induction melting is a commonly used method for preparing AlV55 alloys. However, this method results in high Al evaporation losses, leading to poor cost control. Moreover, the influence of the process parameters on the alloy composition remains unclear. In this study, the evaporation pattern of Al in the melting and preparation processes of AlV55 alloys is studied, and measures for controlling the system pressure are proposed to effectively reduce Al evaporation. The experimental results show that smelting under an Ar gas atmosphere of 2000 Pa can reduce the evaporation loss of Al from 11.48% under vacuum conditions (60 Pa) to 0.58% of the amount of raw material added, effectively improving the metal utilization rate and reducing production costs. The influence of various process parameters on the alloy composition and Al volatilization are investigated to enable the effective control of the compositional uniformity and impurity content of the resulting alloys. Under optimal conditions, the impurity contents of C, O, and N are 0.03%, 0.0073%, and 0.013%, respectively; this reduces the amount of Al lost by evaporation compared to conventional methods, and the alloy produced meets commercial standards.

Experimental investigation on punch shear strength of poly lactic acid specimens for biomedical applications.

The designed biomedical implants require excellent shear strength primarily for mechanical stability against forces in human body. However, metallic implants undergo stress shielding with release of toxic ions in the body. Thus, Fused Deposition Modeling (FDM) has made significant progress in the biomedical field through the production of customized implants. The mechanical behavior is highly dependent on printing parameters, however, the effect of these parameters on punch shear strength of ASTM D732-02 standard specimens has not been explored. Thus, in the current study, the effect of infill density (IFD), printing speed (PTS), wall thickness (WLT), and layer thickness (LYT) has been investigated on the punch shear strength using Response Surface Methodology. The Analysis of Variance (ANOVA) has been performed for predicting statistical model with 95% confidence interval. During the statistical analysis, the terms with p-value lower than 0.05 were considered significant and the influence of process parameters has been examined using microscopic images. The surface plots have been used for discussing the effect of interactions between printing parameters. The statistical results revealed IFD as the most significant contributing factor, followed by PTS, LYT, and WLT. The study concluded by optimization of printing parameters for obtaining the highest punch shear strength.

Impact of process parameters on the dynamic behavior of Inconel 718 fabricated via laser powder bed fusion

In this research, we investigate the dynamic behavior of Inconel 718 fabricated through laser powder bed fusion (L-PBF), addressing a notable knowledge gap regarding the correlation between process parameters and dynamic properties. The process parameters adopted are deducted from an extension of the Rosenthal solution, formulated to increase the process productivity while avoiding the typical production process defects. The dynamic Young modulus and the structural damping of the material are estimated as a function of the process parameters through ping tests reproducing the flexural vibrations of the specimens in as-built, solutioned, and aged conditions. The microstructure and porosity are investigated through metallographic analyses. The results show a substantial influence of the L-PBF process parameters on the dynamic Young modulus, which markedly increases as the energy density is reduced (23%) and progressively becomes more similar to the conventionally produced material. This influence stands in stark contrast to the relatively modest impact of heat treatments, which underlines a negligible effect of the process-induced residual stress. The structural damping remained approximately constant across all test conditions. The elastic response of the material is found to be primarily influenced by the different microstructures produced as the L-PBF process parameters varied, particularly in terms of the dimensions and shape of the solidification structures. The unexpected relationship between the dynamic Young modulus, energy density, and microstructure unveils the potential to fine-tune the material’s dynamic behavior by manipulating the process parameters, thereby carrying substantial implications for all the applications of additively manufactured components susceptible to significant vibratory phenomena.

Effects of carbonization temperature and time on the characteristics of carbonized sludge.

To investigate the influence of carbonization process parameters on the characteristics of municipal sludge carbonization products, this study selected carbonization temperatures of 300-700 °C and carbonization times of 0.5-1.5 h to carbonize municipal sludge. The results showed that with an increase in temperature and carbonization time, the sludge was carbonized more completely, and the structure and performance characteristics of the sludge changed significantly. Organic matter was continuously cracked, the amorphous nature of the material was reduced, its morphology was transformed into an increasing number of regular crystalline structures, and the content of carbon continued to decrease, from the initial 52.85 to 38.77%, while the content of inorganic species consisting continued to increase. The conductivity was reduced by 87.8%, and the degree of conversion of salt ions into their residual and insoluble states was significant. Natural water absorption in the sludge decreased from 8.13 to 1.29%, and hydrophobicity increased. The dry-basis higher calorific value decreased from 8,703 to 3,574 kJ/kg. Heavy metals were concentrated by a factor of 2-3, but the content of the available state was very low. The results of this study provide important technological support for the selection of suitable carbonization process conditions and for resource utilization.

Influence of Process Parameters on the Efficiency of Pervaporation Pilot ECO-001 Plant for Raw Ethanol Dehydration.

Pervaporation is a membrane-based process used for the separation of liquid mixtures. As this membrane process is governed by the differences in the sorption and diffusivities of separated components, close boiling mixtures and azeotropic mixtures can effectively be separated. The dehydration of ethanol is the most common application of hydrophilic pervaporation. The pilot scale properties of hydrophilic composite poly(vinyl alcohol) PVA membrane (PERVAPTM 2200) in contact with wet raw bioethanol are presented. The wet raw bioethanol was composed of ethanol (82.4-89.6 wt%), water (5.9-8.5 wt%), methanol (2.3-6.9 wt%), cyclohexane (0.2-2.4 wt%), higher alcohols (0.2-1.3 wt%), and acetaldehyde (0.004-0.030 wt%). All experiments were performed using a SULZER ECO-001 plant equipped with a 1.5 m2 membrane module. The efficiency of the dehydration process (i.e., membrane selectivity, permeate flux, degree of dehydration) was discussed as a function of the following parameters: the feed temperature, the feed composition, and the feed flow rate through the module. It was found that the low feed flow rate influenced the dehydration efficiency as the enthalpy of evaporation caused a high temperature drop in the module (around 25 °C at a feed flow rate equal to 5 kg h-1). The separation coefficient during pervaporation was in the range of 600-1200, depending on the feed composition. The increase in temperature augmented the permeation flux and shortened the time needed to reach the assumed level of dehydration. It was revealed that dehydration by pervaporation using ECO-001 pilot plant is an efficient process, allowing also to investigate the influence of various parameters on the process efficiency.

Addition of Modifying Agents vs Basic Functional Properties of Moldings Made of ABS

Unconventional injection methods include i.e. blowing injection that allows for production of moldings with a lower weight while maintaining mechanical properties of detail. Due to the fact that most polymers are dyed at the processing stage, it is important to examine the simultaneous effect of blowing and colorbatch, as well as variable processing conditions, on the functional properties of moldings made of the most popular construction material, i.e. ABS. Samples were made of ABS polymer without and with the addition of a colorbatch containing brown pigment on ABS matrix, and blowing agent. Variable processing conditions were: mold and injection temperature, holding pressure and time. Other parameters were constant. Samples were tested for basic functional properties such as color, gloss, mass, density and thickness. Moldings produced with a higher blowing agent content and a higher injection temperature were characterized by lower mass. No significant influence of processing parameters and content of colorbatch on mass of samples was found. Blowing agent has no significant impact on thickness of moldings, regardless of processing conditions. Addition of a colorbatch influenced samples’ gloss. Increase in colorbatch and blowing agent content and mold temperature allow to obtain moldings with a higher surface gloss. Colorbatch also changed color of samples – a decrease in luminance L even by about 40% and great changes in parameters “a” and slight changes in parameter “b”. It was found that blowing agent content had the greatest influence on density of moldings. Injection temperature and colorbatch, do not significantly affect density of moldings.

Direct nanosecond laser metallization of AlN ceramics

In this paper, a study of the influence of laser processing parameters with pulsed nanosecond laser radiation on the degree of metallization and the quality of the metallized surface of aluminum nitride ceramics is presented. Experiments were carried out to create conductive structures with the lowest resistance using direct laser metallization. The dependences of resistance on duration, pulse overlap, and laser fluence were obtained and analyzed, and changes in surface roughness were considered. In addition, the composition of the surface of laser-metallized ceramics was studied using energy-dispersive x-ray spectroscopy. As a result, it was shown that the resistance is inversely proportional to the square root of the pulse duration, the thermal diffusion length was estimated as lT = 8.2 μm for 200 ns and lT = 1.2 μm for 4 ns, and the presence of optimal values of pulse overlap Oy (scanning direction) equal to 50% and pulse overlap Ox (step direction) equal to 96% and 99.7% for pulse durations of 200 and 4 ns, respectively, was determined. The choice of optimal pulse overlaps with the highest laser fluence allowed us to obtain the minimum resistance value with maximum performance.

Preparation and Characterization of Bismaleimide-Resin-Based Composite Materials.

This study utilized bismaleimide (BMI) resin, reinforced with introduced ether bonds, as a binding matrix, in combination with silicon carbide (SiC), for the fabrication of composite materials. A thorough investigation was conducted to assess the influence of diverse processing parameters on the mechanical properties and high-temperature thermo-oxidative stability of these composites. Experimental results indicate a notable improvement in the mechanical properties of the composites upon the incorporation of ether bonds, in contrast to their unmodified counterparts. The variation in performance among composites with different ratios and molding densities is apparent. Within a certain range, an increase in resin content and molding density is correlated with improved bending strength in the composites. With a resin content of 27.5 vol% and a molding density of 2.31 g/cm3, the composite achieved a maximum flexural strength of 109.52 MPa, representing a 24% increase compared to its pre-modification state. Even after exposure to high-temperature heat treatment, the composites displayed commendable mechanical properties compared to their pre-ether bond modification counterparts, maintaining 74.5% of the strength of the untreated composites at 300 °C. The scanning electron microscopy (SEM) microstructures of composite materials correlate remarkably well with their mechanical properties.

Laser‐Crystallization of TiO2 Nanotubes for Photocatalysis: Influence of Laser Power and Laser Scanning Speed

AbstractTitanium dioxide (TiO2) nanotubes have raised significant attention in the field of photocatalysis. However, achieving locally‐confined, tunable, and efficient crystallization remains challenging. Laser crystallization that enables surface‐confined, fast, and localized annealing has emerged as an alternative to calcination of TiO2 nanotubes. Nonetheless, questions regarding crystallization parameters and mechanism remain open. In this work, amorphous TiO2 nanotubes are synthesized by a two‐step anodization process and laser exposed (515 nm, 1 MHz, 250 fs, 256–569 mW, 1–200 mm s−1) to study the impact of laser parameters and the mechanism of laser crystallization. A thorough analysis via Raman spectroscopy, X‐ray diffraction, scanning electron microscopy, UV–vis spectroscopy, transmission electron microscopy, and degradation of methylene blue is performed and the influence of laser processing parameters on the crystallization are studied and discussed. As laser power increases, a gradual transition from amorphous to anatase and rutile phase takes place, consistent with a thermal crystallization mechanism. Contrary, with increasing laser scanning speeds, thus lower pulse numbers, anatase is converted to rutile and melting occurs. The degradation of methylene blue with anatase samples crystallized by laser and calcination exhibits equal kinetic degradation constants of 0.013 s−1cm−2. This study enhances the understanding of laser crystallization of TiO2 nanotubes.

Data‐Driven Cz–Si Scale‐Up under Conditions of Partial Similarity

AbstractIn Cz–Si growth, the shape of the solid–liquid interface and the v/G ratio significantly impact crystal quality. This study utilizes a data‐driven approach, employing multilayer perceptron (MLP) neural networks and Bayesian optimization, to investigate the scale‐up process of Cz–Si under conditions of partial similarity. The focus is on exploring the influence of various process and furnace geometry parameters, as well as radiation shield material properties, on the critical measures of crystal quality. Axisymmetric CFD modeling produces 340 sets of 18D raw data, from which 14‐dimensionless derived data tuples are generated for the design and training of the MLP. The best MLP obtained demonstrates the ability to accurately assess the complex nonlinear dependencies among dimensionless numbers derived from CFD data and, on the output side, interface deflection and v/G. These relationships, crucial for scale‐up, are successfully generalized across a wide range of parameters.

Development and characterization of stable proanthocyanidin‐loaded PLAROsomes as a potential drug carrier system for augmenting anticancer activity

AbstractThe aim of the present study was to develop potential drug carrier system formulations, namely PLAROsomes for the delivery of Proanthocyanidin (PACY), isolated from the extract of dried grape seeds. The PLAROsomes loaded with PACY were prepared using the thin film hydration method. The influence of various process parameters and material attributes was investigated using the design of experiments (DoE). The PACY‐loaded PLAROsomes were characterized using hyphenated tools. The in‐vitro anticancer activities of PACY‐loaded PLAROsomes were confirmed using the Trypan blue method, MTT method, and flow cytometric analysis on MCF‐7 cells. The polymer‐to‐lipid ratio, among various process parameters and material attributes, significantly influenced the average particle size. Additionally, it played a crucial role in determining the percentage of PACY released from PACY‐loaded PLAROsomes. The size of the PACY‐loaded PLAROsomes ranged from 40 to 300 nm, and the optimized batch demonstrated a drug entrapment efficiency of 86.38±0.22%. PACY‐loaded PLAROsomes exhibited improved in vitro anticancer activities against MCF‐7 breast cancer cell lines compared to PACY. PACY‐loaded PLAROsomes showed greater activity at lower concentrations in cytotoxicity studies, as supported by apoptosis analysis. Therefore, PLAROsomes could present a promising drug carrier system for delivering PACY in breast cancer treatment, offering a sustained release effect.

The Factors Influencing Lithium Carbonate Crystallization in Spent Lithium-Ion Battery Leachate

In this study, lithium was recovered from spent lithium-ion batteries through the crystallization of lithium carbonate. The influence of different process parameters on lithium carbonate precipitation was investigated. The results indicate that under the conditions of 90 °C and 400 rpm, a 2.0 mol/L sodium carbonate solution was added at a rate of 2.5 mL/min to a 2.5 mol/L lithium chloride solution, yielding lithium carbonate with a recovery rate of 85.72% and a purity of 98.19%. The stirring rate and LiCl solution concentration significantly impact the particle size of lithium carbonate aggregates. As the stirring rate increases from 200 to 800 rpm, the average particle size decreases from 168.694 μm to 115.702 μm. Conversely, an increase in the LiCl solution concentration reduces the lithium carbonate particle size, with an average particle size of only 97.535 μm being observed at a LiCl solution concentration of 2.5 mol/L. It was also observed that nickel and cobalt ions become incorporated into the crystal lattice of lithium carbonate, thereby affecting the growth and morphology of lithium carbonate.

Improving the actuation behavior of nitinol shape memory alloys by nanosecond laser surface texturing

Laser surface texturing of nitinol was performed using a nanosecond fiber laser to modify the surface structure and enhance the laser actuation performance of nitinol. The influence of laser processing parameters on surface morphology and chemical composition was studied in detail. The influence of texturing on the laser actuation behavior was evaluated using a continuous wave fiber laser and a CO2 laser. Compared to the pristine sample, the textured samples demonstrated better displacements and faster actuation. During laser actuation using a fiber laser, the textured sample showed maximum and minimum displacement enhancements of 65% and 15%, respectively. The actuation performance of the textured sample was approximately twice that of the pristine sample during the irradiation with CO2 laser. This paper presents the viability of laser surface texturing to enhance the actuation performance of shape memory alloys, and the results indicate that the power required for actuation can be reduced to avoid the use of bulky power and control units.

Study on the grain evolution of austenitic steel for nuclear power during hot working based on large area EBSD mapping

To address the issue of non-standard grain sizes and difficult control of uniformity in the manufacturing of large, complex-shaped nuclear power pipelines. In this paper, double wedge-shaped samples of X2 CrNiMo 18.12 (CN) austenitic stainless steel were hot deformed at 1000 °C, 1100 °C, and 1180 °C to obtain deformation samples with a gradient strain, and the deformation sample at 1180 °C was subjected to solid solution treatment at 1060 °C × 4 h (water quenching; the measured cooling rate of water cooling was approximately 4400 °C/min). Large-area electron backscattered diffraction mapping technology was used to characterize the 80 mm × 5 mm full-area range of samples. The initiation sequence of various dynamic recrystallization mechanisms and the grain evolution under continuous effective strain conditions at a hot deformation temperature of 1000–1180 °C were investigated. The influence of the hot deformation process parameters on the grains after solid solution treatment was examined, the process interval for the generation of severe mixed grains was determined. The results show that the recrystallization behavior of X2 CrNiMo 18.12 (CN) austenitic stainless steel is mainly determined by a combination of recrystallization mechanisms dominated by discontinuous dynamic recrystallization, supplemented by continuous dynamic recrystallization, twinning-induced dynamic recrystallization, and geometrical dynamic recrystallization during the hot deformation process at 1000–1180 °C. The effective strain intervals of the solid solution sample that produces severely mixed grains are in the range of 0.11–0.22 mm/mm, with the probability of producing severely mixed grains with an effective strain in the range of 0.13–0.14 mm/mm reaching 74%.

Optimization of the process parameters for vertical centrifugal casting of A356 by numerical simulation

This paper investigates the influence of critical process parameters on the centrifugal casting of A356 (Al-Si) alloys using a casting simulation tool. Effects of mould rotation, pouring temperature, mould aspect ratio, and heat transfer coefficient on filling and solidification behaviours have been studied. Furthermore, the study employs Grey Relation Analysis, Taguchi, and ANOVA to systematically optimize the casting process parameters, addressing uncertainties and identifying statistically significant factors. Process optimization, supported by numerical simulations, has revealed that the optimal configuration (rotation of 150 rpm, aspect ratio as 2, pouring temperature as 775 °C) minimizes stress and strain (maximum shear stress, average normal stress, principal stress, principal strain) that can be considered to be responsible for the occurrence of defects such as cracks in final castings. Controlling these process parameters will help in reducing overall stresses and in turn reducing defects as well as improvement of overall productivity.