12 research outputs found

    Parameter influence on the tensile properties of FDM printed PLA/ coconut wood

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    Due to its adaptability in allowing for individualized production, 3D printing technology has quickly become a viable option in the fabrication of parts. Recent years have seen a plethora of research devoted to enhancing the quality of 3D-printed components. However, the performance of the printed part depends heavily on the correct selection of process parameters for Fused deposition modelling (FDM), making it a significant task. Therefore, studying how different process parameters affect the final product's quality characteristics is essential. So, it's helpful if there's a good option for customizing the mechanical properties of 3D-printed components. This study aims to determine how factors affect the tensile properties of a composite made from PLA and coconut wood. The material in the form of a filament, such as thermoplastic polymers, was used. Coconut wood has been prized for centuries for its durability, beauty, and ecological friendliness. This research aims to create and compare the tensile properties of specimens featuring different infill patterns (concentric, cubic, gyroid, and triangle) and infill percentages (25%, 50%, 75%). Ultimate tensile strength of 37.21 MPa and elastic modulus of 1.12 GPa were achieved with the concentric infill pattern at 75% infill

    Characterisation, performance and optimisation of nanocellulose metalworking fluid (MWF) for green machining process

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    The present research attempts to develop a hybrid coolant by mixing alumina nanoparticles with cellulose nanocrystal (CNC) into ethylene glycol-water (60:40) and investigate the viability of formulated hybrid nanocoolant (CNC-Al2O3-EG-Water) towards enhancing the machining behavior. The two-step method has been adapted to develop the hybrid nanocoolant at various volume concentrations (0.1, 0.5, and 0.9%). Results indicated a significant enhancement in thermal properties and tribological behaviour of the developed hybrid coolant. The thermal conductivity improved by 20-25% compared to the metal working fluid (MWF) with thermal conductivity of 0.55 W/m℃. Besides, a reduction in wear and friction coefficient was observed with the escalation in the nanoparticle concentration. The machining performance of the developed hybrid coolant was evaluated using Minimum Quantity Lubrication (MQL) in the turning of mild steel. A regression model was developed to assess the deviations in the tool flank wear and surface roughness in terms of feed, cutting speed, depth of the cut, and nanoparticle concentration using Response Surface Methodology (RSM). The mathematical modeling shows that cutting speed has the most significant impact on surface roughness and tool wear, followed by feed rate. The depth of cut does not affect surface roughness or tool wear. Surface roughness achieved 24% reduction, 39% enhancement in tool length of cut, and 33.33% improvement in tool life span. From this, the surface roughness was primarily affected by spindle cutting speed, feed rate, and then cutting depth while utilising either conventional water or composite nanofluid as a coolant. The developed hybrid coolant manifestly improved the machining behaviour

    Statistical model for impact and energy absorption of 3D printed coconut Wood-PLA

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    Fused deposition modeling (FDM)-3D printing has been the favored technology to build functional components in various industries. The present study investigates infill percentage and infill pattern effects on the printed parts’ impact properties through the 3D printing technique using coconut wood-filled PLA composites. Mathematical models are also proposed in the present study with the aim for future property prediction. According to the ASTM standard, fifteen specimens with different parameter combinations were printed using a low-cost FDM 3D printer to evaluate their impact properties. Statistical analysis was performed using MINITAB to validate the experimental data and model development. The experimental outcomes reveal the honeycomb pattern with 75% infill density achieves the highest energy absorption (0.837 J) and impact energy (5.1894 kJ/m2). The p-value from statistical analysis clearly shows that all the impact properties are less than the alpha value of 0.05, suggesting all the properties are vital to determine the impact properties. The validation process affirms that the generated mathematical model for the energy absorbed and the impact energy is reliable at an acceptable level to predict their respective properties. The errors between the experimental value and the predicted value are 3.98% for the energy absorbed and 4.06% for impact energy. The findings are expected to provide insights on the impact behavior of the coconut wood-filled PLA composites prepared by FDM-3D printing and a mathematical model to predict the impact properties

    A human tau seeded neuronal cell model recapitulates molecular responses associated with Alzheimer's disease

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    Cellular models recapitulating features of tauopathies are useful tools to investigate the causes and consequences of tau aggregation and the identification of novel treatments. We seeded rat primary cortical neurons with tau isolated from Alzheimer's disease brains to induce a time-dependent increase in endogenous tau inclusions. Transcriptomics of seeded and control cells identified 1075 differentially expressed genes (including 26 altered at two time points). These were enriched for lipid/steroid metabolism and neuronal/glial cell development genes. 50 genes were correlated with tau inclusion formation at both transcriptomic and proteomic levels, including several microtubule and cytoskeleton-related proteins such as Tubb2a, Tubb4a, Nefl and Snca. Several genes (such as Fyn kinase and PTBP1, a tau exon 10 repressor) interact directly with or regulate tau. We conclude that this neuronal model may be a suitable platform for high-throughput screens for target or hit compound identification and validation

    Preliminary Tensile Investigation of FDM Printed PLA/Coconut Wood Composite

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    Fused Deposition Modeling (FDM) is an of additive manufacturing method that has been used to create multiple components from a variety of materials for a wide range of applications in layer-by-layer deposition. The thermoplastic polymers were used as a material which comes in the form of a filament. Coconut wood is highly recognized for its naturally affable, ecological components, thermal resilience, and corrosion resistance up to the present day. However, PLA's characteristics embedded in coconut wood remain limited. The aim of this study is to create and analyse the tensile properties of the specimens with varying infill percentages (25%, 50%, and 75%) and the infill patterns (grid, rectilinear, concentric, honeycomb, and triangle) on coconut wood reinforced PLA using the FDM technique. The specimen is printed in accordance with the ASTM standard for tensile testing which is ASTM D638 type 1. Following that, the tensile properties of the PLA and PLA-coconut wood were analysed. The results demonstrate that the concentric infill pattern with a percentage of infill 75% of pure PLA produced 37.55 MPa of Ultimate tensile strength and the maximum elastic modulus of 1.148 GPa and yield strength of 23.33 Mpa in tensile testing meanwhile the Grid pattern has the weakest properties among all the patterns

    Electrochemical Deposited Nickel Nanowires: Influence of Deposition Bath Temperature on the Morphology and Physical Properties

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    This paper investigates the influence of the electrolytic bath temperature on the morphology and physical properties of nickel (Ni) nanowires electrochemically deposited into the anodic alumina oxide porous membrane (AAO). The synthesis was performed using nickel sulfate hexahydrate (NiSO4.6H2O) and boric acid (H3BO3) as an electrolytic bath for the electrochemical deposition of Ni nanowires. During the experiment, the electrolyte bath temperature varied from 40°C, 80°C, and 120°C. After the electrochemical deposition process, AAO templates cleaned with distilled water preceding to dissolution in sodium hydroxide (NaOH) solution to obtain free-standing Ni nanowires. Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive Spectroscopy (EDX) and X-ray Diffraction (XRD) analysis were employed to characterize the morphology and physical properties of the synthesized Ni nanowires. Finding reveals the electrodeposition bath temperature significantly influences the morphology and physical properties of the synthesized Ni nanowires. Rougher surface texture, larger crystal size, and longer Ni nanowires obtained as the deposition bath temperature increased

    Quantification of Epstein-Barr virus DNA load, interleukin-6, interleukin-10, transforming growth factor-β1 and stem cell factor in plasma of patients with nasopharyngeal carcinoma

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    BACKGROUND: Nasopharyngeal carcinoma (NPC) is a common epithelial neoplasm among the Chinese populations in Southern China and South East Asia. Epstein-Barr virus (EBV) is known to be an important etiologic agent of NPC and the viral gene products are frequently detected in NPC tissues along with elevated antibody titres to the viral proteins (VCA and EA) in a majority of patients. Elevated plasma EBV DNA load is regarded as an important marker for the presence of the disease and for the monitoring of disease progression. However, other serum/plasma parameters such as the levels of certain interleukins and growth factors have also been implicated in NPC. The objectives of the present study are, 1) to investigate the correlations between plasma EBV DNA load and the levels of interleukin (IL)-6, IL-10, TGF-β1 and SCF (steel factor) and 2) to relate these parameters to the stages of NPC and the effect of treatment. METHODS: A total of 78 untreated NPC patients were enrolled in this study. Of these, 51 were followed-up after treatment. The remaining patients had irregular or were lost to follow-up. Plasma EBV DNA was quantified using real-time quantitative PCR. The levels of plasma interleukins and growth factors were quantified using ELISA. RESULTS: A significant decrease in EBV DNA load was detected in plasma of untreated NPC patients (1669 ± 637 copies/mL; n = 51) following treatment (57 ± 37 copies/mL, p < 0.05); n = 51). Plasma EBV DNA load was shown to be a good prognosticator for disease progression and clinical outcome in five of the follow-up patients. A significant difference in IL-6 levels was noted between the untreated patients (164 ± 37 pg/mL; n = 51) and following treatment (58 ± 16 pg/mL, p < 0.05; n = 51). Positive correlations between EBV DNA load and IL-10 (r(49) = 0.535, p < 0.01), between IL6 and IL-10 (r(49) = 0.474, p < 0.01) and between TGF and SCF (r(49) = 0.464, p < 0.01) were observed in patients following treatment. None of the parameters tested including IgA-VCA were associated with tumour stages. CONCLUSION: We conclude that among the parameters investigated, EBV DNA load and IL-6 levels were promising markers for the presence of NPC and for the assessment of treatment outcome

    Influence of boric acid (H3BO3) concentration on the physical properties of electrochemical deposited nickel (Ni) nanowires

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    We have investigated the influence of the stabilizer (Boric Acid) concentration during the template-assisted electrochemical deposition of Nickel (Ni) nanowires in Anodic Alumina Oxide (AAO) templates. The synthesis was performed using Ni Sulfate Hexahydrate (NiSO4.6H2O) as metal salts and Boric Acid (H3BO3) as a stabilizer. The mixture of both solutions creates electrolyte and utilized for the electrochemical deposition of Ni nanowires. During the experiment, the boric acid concentration varied between 5 g/L, 37.5 g/L and 60 g/L with a deposition temperature of 80 °C (constant). After the electrochemical deposition process, AAO templates were cleaned with distilled water before dissolution in Sodium Hydroxide (NaOH) solution to obtain the freestanding Ni nanowires. Physical properties of the synthesized Ni nanowires were analyzed using Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive Spectroscopy (EDX) and X-ray Diffraction (XRD). We elaborate the physical properties of obtained Ni nanowires by taking into account the effect of boric acid concentration on the surface morphology, growth length, elemental composition and crystal orientation crystal of the synthesized nickel nanowires. The finding exposes that the boric acid concentration does not influence all aspects in the physicals properties of the synthesized Ni nanowires. The boric acid concentration did not affect the surface texture and crystal orientation. However, shorter Ni nanowires obtained as the concentration of boric acid increase
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