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Modelling of fiber suspension in injection molding cavities is very complex, with fluid flow, fiber orientation, and heat transfer effects taking place at the same time. Moreover, the flow is modified by the presence of fibers and vice versa. Therefore, the aim of the paper is to develop a Computational Fluid Dynamics (CFD) model to simulate and characterise the fiber suspension flow in two dimensional mold cavities. The model is intended to describe the fluid flow and heat transfer aspects of the suspension, and to predict the fiber orientation. The Navier-Stokes equations and the Jeffery (1922) equation are the governing equations for the velocity field and fiber motion respectively. The flow is considered to be two-dimensional incompressible, non-isothermal, transient and behave as non-Newtonian fluid containing suspension of short-fibers. The Finite Volume Method (FVM) combined with Control Volume Method is used to simulate the flow field by solving the momentum, energy and fiber orientation equations. To validate the numerical model, the numerical results are compared with available experimental findings. A good agreement between the numerical results and the experimental data is achieved. Since the behaviour of fiber suspension has great significance on the quality of the final product, this study has wide background of engineering application.

The orientation behavior of fiber is of great significance in improving the performance of fiber-reinforced polymer products. Generally, the Folgar–Tucker equation can accurately describe the variation of orientation vector of fiber, whereas the stability of numerical algorithms was the major challenge. This paper aims to propose an accurate, stable algorithm to solve the Folgar–Tucker equation for the fiber orientation behavior.

First, the mismatch problem between the strain rate and the pressure field was solved by using the integral transformation method. Then, an accurate, stable algorithm to solve the Folgar–Tucker equation based on the invariant-based optimal fitting method was proposed. The equation was discretized by finite element/finite difference method, and the Lagrange multiplier method was applied to ensure stability.

The proposed algorithm is proven to accurately and steadily coincide with the experimental results for different cases, including the fiber orientation behaviors under combined flow field, rectangular sheet, three-dimensional computed tomography imaging of tensile specimen and box cases.

The fiber orientation behavior during the injection molding can be accurately predicted, which plays a significant role in determining the mechanical properties of products.

The purpose of this study was to fabricate carbon nanotubes (CNT)-reinforced chromium oxide coatings and investigate mechanical and microstructural properties of these newly developed coatings on the boiler tube steel.

1 and 4 Wt.% CNT-reinforced Cr₂O₃ composite coatings were prepared and successfully deposited on ASTM-SA213-T22 (T22) boiler tube steel substrates using high-velocity oxy fuel (HVOF) thermal spraying method. Microhardness, porosity, metallography, X-ray diffraction (XRD), scanning electron microscopy (SEM)/energy-dispersive X-ray spectroscopy, cross-sectional elemental analysis and X-ray mapping analysis have been used to examine the coated specimens.

The porosity of the CNT-Cr₂O₃ composite coatings was found to be decreasing with the increases in CNT content, and hardness has been found to be increasing with increase in percentage of CNT in the composite coatings. The CNT were able to increase hardness by approximately 17 per cent. It was found that the CNT were uniformly distributed throughout Cr₂O₃ matrix. The CNT were found to be chemically inert during the spraying process.

It must be mentioned here that studies related to fabrication of HVOF sprayed CNT reinforced Cr₂O₃ composite coatings on T22 boiler tube steel are not available in the literature. Hence, present investigation can provide valuable information related to fabrication and properties of CNT reinforced coatings on boiler steel.

This paper aims to investigate hot corrosion behaviour of different Cr₃C₂–NiCr coatings on boiler tube steel.

High velocity oxy fuel technique has been used to deposit different coatings on commercially available ASTM-SA213-T22 boiler tube steel. The hot corrosion studies have been performed in molten salt environment at 900°C temperature in silicon tube furnace in laboratory.

The results showed that uncoated superalloy suffered intense spalling and the weight change was massive during each cycle on studies of hot corrosion 900°C. The 100 per cent NiCr and 10 per cent (Cr₃C₂) – 90 per cent (NiCr) coatings provided better protection to T22 steel against the hot corrosion because of the formation of Ni and Cr₃C₂ layers.

In this research a variety of coatings have been used. This research work has been aimed to investigate the hot corrosion behavior of Boiler Steel b with different Cr₃C₂–NiCr coatings, under molten salt environment in Silicon tube furnace at 900°C, under cyclic conditions.

The aim of this article is to demonstrate the development of environment friendly, low cost natural fibre composites by robust engineering approach. More specifically, the prime objective of the study is to optimise the composition of natural fibre reinforced polymer nanocomposites using a robust statistical approach.

In this research, the material is prepared using multi-walled carbon nanotubes (MWCNT), Cantala fibres and Epoxy Resin in accordance with the ASTM (American Society for Testing and Materials) standards. Further, the composition is prepared and optimised using the mixture-design approach for the flexural strength of the material.

The results of the study indicate that MWCNT plays a vital role in increasing the flexural strength of the composite. Moreover, it is observed that interactions between second order and third order parameters in the composition are statistically significant. This leads to proposing a special cubic model for the novel composite material with residual analysis. Moreover, the methodology assists in optimising the mixture component values to maximise the flexural strength of the novel composite material.

This article attempts to include both MWCNT and Cantala fibres to develop a novel composite material. In addition, it employs the mixture-design technique to optimise the composition and predict the model of the study in a step-by-step manner, which will act as a guideline for academicians and practitioners to optimise the material composition with specific reference to natural fibre reinforced nanocomposites.

The purpose of this paper was to investigate the lubricity of palm biodiesel (PB)–diesel fuel with plastic pyrolysis oil (PPO) and waste cooking biodiesel (WCB).

Three quaternary fuels were prepared by mechanical stirring. B10 (10% PB in diesel) fuel was blended with 5%, 10% and 15% of both PPO and WCB. The results were compared to B30 (30% PB in diesel) and B10. The lubricity of fuel samples was determined using high-frequency reciprocating rig in accordance with ASTM D6079. The tribological behavior of all fuels was assessed by using scanning electron microscopy on worn steel plates to determine wear scar diameter (WSD) and surface morphology. The reported WSD is the average of the major and minor axis of the wear scar.

The addition of PPO and WCB to B10 had improved its lubricity while lowering wear and friction coefficients. Among the quaternary fuels, B40 showed the greatest reduction in coefficient of friction and WSD, with 7.63% and 44.5%, respectively, when compared to B10. When compared to B30a, the quaternary fuel mixes (B40, B30b and B20) exhibited significant reduction in WSD by 49.66%, 42.84% and 40.24%, respectively. Among the quaternary fuels, B40 exhibited the best overall lubricating performance, which was supported by surface morphology analysis. The evaluation of B40 indicated a reduced adhesive wear and tribo-oxidation, as well as a smoother metal surface, as compared to B20 and B30b.

Incorporation of PPO and WCB in PB–diesel blend as a quaternary fuel blend in diesel engines has not been reported. Only a few researchers looked into the impact of PPO and WCB on the lubricity of the fuel.

This paper aims to demonstrate the synthesis of polyesterification reaction of non-edible jatropha seed oil (JO) and acrylic acid, which leads to the production of acrylated epoxidised-based resin. To understand the physico-chemical characteristics when synthesis the JO-based epoxy acrylate, the effect of temperature on the reaction, concentration of acrylic acid and role of catalyst on reaction time and acid value were studied.

First, the double bond in JO was functionalised by epoxidation using the solvent-free performic method. The subsequent process was acrylation with acrylic acid using the base catalyst triethylamine and 4-methoxyphenol as an inhibitor respectively. The physico-chemical characteristics during the synthesis of the epoxy acrylate such as acid value was monitored and analysed. The formation of the epoxy and acrylate group was confirmed by a Fourier transform infrared spectroscopy spectra analysis and nuclear magnetic resonance analysis.

The optimum reaction condition was achieved at a ratio of epoxidised JO to acrylic acid of 1:1.5 and the reaction temperature of 110°C. This was indicated by the acid value reduction from 86 to 15 mg KOH/g sample at 6 hours.

The JO-based epoxy acrylate synthesised has a potential to be used in formulations the prepolymer resin for UV curable coating applications. The JO which is from natural resources and is sustainable raw materials that possible reduce the dependency on petroleum-based coating.

The epoxidised jatropha seed oil epoxy acrylate was synthesised, as a new type of oligomer resin that contains a reactive acrylate group, which can be alternative to petroleum-based coating and can used further in the formulation of the radiation curable coating.

This study aims to investigate the effect of temperature applied at the initial deposition of Aluminium Nitride (AlN) thin-film on a silicon substrate by high-power impulse magnetron sputtering (HiPIMS) technique.

HiPIMS system was used to deposit AlN thin film at a low output power of 200 W. The ramping temperature was introduced to substrate from room temperature to maximum 100°Cat the initial deposition of thin-film, and the result was compared to thin-film sputtered with no additional heat. For the heat assistance AlN deposition, the substrate was let to cool down to room temperature for the remaining deposition time. The thin-films were characterized by X-ray diffraction (XRD) and atomic force microscope (AFM) while the MIS Schottky diode characteristic investigated through current-voltage response by a two-point probe method.

The XRD pattern shows significant improvement of the strong peak of the c-axis (002) preferred orientation of the AlN thin-film. The peak was observed narrowed with temperature assisted where FWHM calculated at 0.35° compared to FWHM of AlN thin film deposited at room temperature at around 0.59°. The degree of crystallinity of bulk thin film was improved by 28% with temperature assisted. The AFM images show significant improvement as low surface roughness achieved at around 0.7 nm for temperature assisted sample compares to 3 nm with no heat applied.

The small amount of heat introduced to the substrate has significantly improved the growth of the c-axis AlN thin film, and this method is favorable in the deposition of the high-quality thin film at the low-temperature process.

This paper aims to investigate the corrosion behavior of zinc in a typical hot and dry atmosphere. It proposes the dynamic corrosion for different exposure periods. Results can provide the basic data and corrosion mechanism of zinc in such environment.

In this paper, the authors investigated the corrosion behavior of pure zinc exposed in the typical hot and dry environment in Turpan for one-four years, which has never been studied. Scanning electron microscopy, laser scanning confocal microscopy, electron probe micro-analyzer (EPMA), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) were conducted to measure the corrosion morphology and products of zinc. Finally, combining electrochemical impedance spectroscopy and scanning Kelvin probe techniques, the corrosion mechanism of zinc in Turpan was examined.

The thickness loss of the zinc followed an exponential law with respect to exposure time: D = 3.17 t^0.61, and both of the rust layer resistance and the charge transfer resistance increased with exposure time. The corrosion products mainly comprised ZnO, Zn(OH)₂, Zn₅(CO₃)₂(OH)₆, Zn₄SO₄(OH)₆·5H₂O and Zn₁₂(SO₄)₃Cl₃(OH)₁₅·5H₂O. The Kelvin potentials shifted toward the positive direction from −0.380 to −0.262 V (vs saturated calomel electrode [SCE]) when the exposure time extended from one to four years and the distribution of the corrosion products became more and more uniform.

The corrosion behavior of pure zinc in the typical hot and dry environment in Turpan has not been studied. The dynamic corrosion for different exposure periods was obtained. The corrosion products were systemically investigated via energy-dispersive X-ray spectroscopy, EPMA, XPS and XRD.

This study aims to investigate the effects of incorporating seaweed composite flour on soft roll dough rheological characteristics and quality.

In this study, wheat flour was substituted with seaweed powder obtained from red seaweed (Kappaphycus alvarezii) at varying proportions (100:0; 99:1; 98:2; 97:3; 96:4; 95:5, 94:6, 93:7 and 92:8) and applied in soft roll production. The effects of seaweed composite flour were evaluated in terms of rheological characteristics, proximate composition and physical properties. The sensory characteristics of the soft rolls was evaluated by 40 untrained panellists by using a hedonic scale.

Farinograph analysis of the soft roll doughs showed that the incorporation of seaweed powder promoted an increase in water absorption, development time and mixing tolerance index, whereas it decreased stability time. Analysis of the proximate composition of the soft rolls showed that protein and carbohydrate contents decreased, but moisture, ash and crude fibre contents substantially increased. Dietary fibre increased with the increase in the proportion of seaweed powder added. The specific volume, bulk density and firmness of the soft rolls ranged from 3.01 to 5.48 cm³/g, 0.18 to 0.33 g/cm³ and 1.86 to 20.63 N, respectively. Sensory evaluation results showed that the mean score of sensory attributes decreased as the proportion of seaweed powder added was increased in the formulations. With regard to the overall acceptability, the panellists preferred the soft rolls with the least amount of seaweed powder added. The results of hedonic tests revealed that the panellists' acceptance decreased as higher amounts seaweed powder were added in the formulations.

This study showed that the seaweed powder of K. alvarezii can be utilised as an ingredient to improve the nutrient composition of baked products.