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Polymers Aug 2023Understanding the fatigue behaviors of weld joints is significant in engineering practice. Rotary friction welding (RFW) can join the additively manufactured polymer...
Understanding the fatigue behaviors of weld joints is significant in engineering practice. Rotary friction welding (RFW) can join the additively manufactured polymer components. Until now, no research has focused on the fatigue behavior of polymer components jointed via RFW. This study investigates the fatigue life of ABS/PC dissimilar components fabricated via RFW and proposes the fatigue mechanism based on the failure structure. This work uses five different cyclic loads and rotational speeds to investigate the fatigue life. The fatigue life of the RFW of ABS/PC dissimilar rods is better compared with the pure ABS and pure PC specimens due to weld and integrity microstructural changes resulting from the combination of ABS and PC materials. The number of cycles until the rupture of RFW of ABS/PC dissimilar components (y) can be determined by the cyclic load (x) according to the prediction equation of y = -838.25x - 2035.8x + 67,262. The fatigue life of the RFW of ABS/PC dissimilar components increase with the increased rotational speed. The number of cycles until rupture (y) can be determined by the different rotational speeds (x) according to the prediction equation of y = 315.21x + 2710.4x + 32,124.
PubMed: 37631481
DOI: 10.3390/polym15163424 -
Materials (Basel, Switzerland) Nov 2023The expansion and low cost of additive manufacturing technologies have led to a revolution in the development of materials used by these technologies. There are several...
The expansion and low cost of additive manufacturing technologies have led to a revolution in the development of materials used by these technologies. There are several varieties of materials that can be used in additive manufacturing by fused deposition modeling (FDM). However, some of the properties of these materials are unknown or confusing. This article addresses the need to know the thermal conductivity in different filaments that this FDM technology uses, because there are multiple applications for these additive manufacturing products in the field of thermal insulation. For the study of thermal conductivity, the DTC-25 commercial conductivity measurement bench was used, where the tests were carried out on a set of seven different materials with 100% fabrication density-from base materials such as acrylonitrile butadiene styrene (ABS) or polylactic acid (PLA), to materials with high mechanical and thermal resistance such as thermoplastic polyurethane (TPU), polyether ether ketone (PEEK), and high-performance polyetherimide thermoplastic (ULTEM), to materials with metal inclusions (aluminum 6061) that would later be subjected to thermal after-treatments. This study shows how the parts manufactured with aluminum inclusions have a higher thermal conductivity, at 0.40 ± 0.05 W/m·K, compared to other materials with high mechanical and thermal resistance, such as TPU, with a conductivity of 0.26 ± 0.05 W/m·K.
PubMed: 38068128
DOI: 10.3390/ma16237384 -
Journal of Ultrasound Jun 2024The study aims to provide insights on the practicality of using single-element transducers for transcranial Focused Ultrasound (tFUS) thermal applications.
PURPOSE
The study aims to provide insights on the practicality of using single-element transducers for transcranial Focused Ultrasound (tFUS) thermal applications.
METHODS
FUS sonications were performed through skull phantoms embedding agar-based tissue mimicking gels using a 1 MHz single-element spherically focused transducer. The skull phantoms were 3D printed with Acrylonitrile Butadiene Styrene (ABS) and Resin thermoplastics having the exact skull bone geometry of a healthy volunteer. The temperature field distribution during and after heating was monitored in a 3 T Magnetic Resonance Imaging (MRI) scanner using MR thermometry. The effect of the skull's thickness on intracranial heating was investigated.
RESULTS
A single FUS sonication at focal acoustic intensities close to 1580 W/cm for 60 s in free field heated up the agar phantom to ablative temperatures reaching about 90 °C (baseline of 37 °C). The ABS skull strongly blocked the ultrasonic waves, resulting in zero temperature increase within the phantom. Considerable heating was achieved through the Resin skull, but it remained at hyperthermia levels. Conversely, tFUS through a 1 mm Resin skull showed enhanced ultrasonic penetration and heating, with the focal temperature reaching 70 °C.
CONCLUSIONS
The ABS skull demonstrated poorer performance in terms of tFUS compared to the Resin skull owing to its higher ultrasonic attenuation and porosity. The thin Resin phantom of 1 mm thickness provided an efficient acoustic window for delivering tFUS and heating up deep phantom areas. The results of such studies could be particularly useful for accelerating the establishment of a wider range of tFUS applications.
Topics: Phantoms, Imaging; Transducers; Humans; Skull; Brain; Magnetic Resonance Imaging; Hot Temperature; Thermometry; Printing, Three-Dimensional
PubMed: 37517052
DOI: 10.1007/s40477-023-00810-7 -
Mikrochimica Acta Sep 2023A original electrochemical sensing platform, based on screen-printed electrodes modification with plasma polymerized acrylonitrile (pp-AN) nanofilms is proposed. For...
A original electrochemical sensing platform, based on screen-printed electrodes modification with plasma polymerized acrylonitrile (pp-AN) nanofilms is proposed. For that purpose, plasma-enhanced chemical vapor deposition (PECVD) process was conducted in a parallel plate (13.56 MHz) plasma reactor for 2 min with discharge power of 10 W. The surface topography and electrochemical properties of prepared sensors were investigated by X-ray photoelectron spectroscopy, scanning electron microscopy, energy dispersion spectroscopy, electrochemical impedance spectroscopy, and cyclic voltammetry. The electrochemical characteristics of pp-AN/SPCE and pp-AN/SPAuE sensors was investigated for model redox pair [Fe(CN)]. Conducted research confirmed the excellent chemical stability, durability, wide potential window, high signal-to-noise (S/N) ratio, and, most importantly, the ability to standardize the sensors. The pp-AN/SPCE sensor was applied to the determination of bupropion, an antidepressant drug whose intake has increased dramatically during the COVID-19 pandemic. The voltammetric response of pp-AN/SPCE for BUP was linear in two concentration ranges of 0.63-10.0 and 10.0-50.0 μmol L, with a detection limit of 0.21 μmol L. Satisfactory recoveries (96.2-102%) and good precision (RSD below 4.1%) obtained for environmental and biological samples confirmed the usefulness of the sensor for the analysis of various kinds of samples.
PubMed: 37704761
DOI: 10.1007/s00604-023-05971-0 -
Polymers Jun 2024The manufacturing method influences the properties of the produced components. This work investigates the influence of manufacturing methods, such as fused deposition...
Influence of the Manufacturing Method (3D Printing and Injection Molding) on Water Absorption and Mechanical and Thermal Properties of Polymer Composites Based on Poly(lactic acid).
The manufacturing method influences the properties of the produced components. This work investigates the influence of manufacturing methods, such as fused deposition modeling (3D printing) and injection molding, on the water absorption and mechanical and thermal properties of the specimens produced from neat bio-based poly(lactic acid) (PLA) polymer and poly(lactic acid)/wood composites. Acrylonitrile butadiene styrene (ABS) acts as the reference material due to its low water absorption and good functional properties. The printing layer thickness is one of the factors that affects the properties of a 3D-printed specimen. The investigation includes two different layer thicknesses (0.2 mm and 0.3 mm) while maintaining uniform overall thickness of the specimens across two manufacturing methods. 3D-printed specimens absorb significantly higher amounts of water than the injection-molded specimens, and the increase in the layer thickness of the 3D-printed specimens contributes to further increased water absorption. However, the swelling due to water absorption in 3D-printed specimens decreases upon increased layer thickness. The tensile, flexural, and impact properties of all of the specimens decrease after water absorption, while the properties improve upon decreasing the layer thickness. Higher porosity upon increasing the layer thickness is the predominant factor. The results from dynamic mechanical analysis and microscopy validate the outcomes. The results from this experimental study highlight the limitations of additive manufacturing.
PubMed: 38931969
DOI: 10.3390/polym16121619 -
Heliyon Jun 2024Additive manufacturing (AM) has gained significant attention in recent years owing to its ability to fabricate intricate shapes and structures that are often challenging...
Additive manufacturing (AM) has gained significant attention in recent years owing to its ability to fabricate intricate shapes and structures that are often challenging or unattainable using conventional manufacturing techniques. This high-quality development trend entails higher requirements for the structural design of 3D printers. In this study, polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS) filaments were fed through a heated extrusion nozzle, which melted the material and deposited it onto a build platform. This study's objectives are high-gravitational material extrusion (HG-MEX) systems development, analyzing the high gravity influences on the flow behavior of materials during extrusion, and understanding the effects of gravitational on material flow and overall extrusion performance. HG-MEX systems have great potential for addressing various challenges in additive manufacturing, such as precise manufacturing. The highlight of the progress is that we developed an HG-MEX system and applied surface science to material extrusion in different gravity. We established a system and obtained results on different gravity, we analyzed the analogy between different gravity phenomena. We analyzed the interplay between the behavior of the fabricated parts and gravity. We analyzed high gravity effects on extrusion processes. The results confirmed the characteristics and feasibility of the developed system. The results suggest that a material extrusion line operating under 15 G conditions resulted in better printing quality compared to one operating under 1 G conditions. This observation implies that high gravity had a positive effect on the extrusion process, leading to improved material extrusion performance.
PubMed: 38947488
DOI: 10.1016/j.heliyon.2024.e32161 -
Polymers Mar 2024Poly(acrylonitrile-co-methyl acrylate) (PAN-co-MA) electrospun nanofiber (ENF) was used as the support for the formation of polyamide (PA) thin films. The ENF support...
Poly(acrylonitrile-co-methyl acrylate) (PAN-co-MA) electrospun nanofiber (ENF) was used as the support for the formation of polyamide (PA) thin films. The ENF support layer was post-treated with heat-pressed treatment followed by NaOH hydrolysis to modify its support characteristics. The influence of heat-pressed conditions and NaOH hydrolysis on the support morphology and porosity, thin-film formation, surface chemistry, and membrane performances were investigated. This study revealed that applying heat-pressing followed by hydrolysis significantly enhances the physicochemical properties of the support material and aids in forming a uniform polyamide (PA) thin selective layer. Heat-pressing effectively densifies the support surface and reduces pore size, which is crucial for the even formation of the PA-selective layer. Additionally, the hydrolysis of the support increases its hydrophilicity and decreases pore size, leading to higher sodium chloride (NaCl) rejection rates and improved water permeance. When compared with membranes that underwent only heat-pressing, those treated with both heat-pressing and hydrolysis exhibited superior separation performance, with NaCl rejection rates rising from 83% to 98% while maintaining water permeance. Moreover, water permeance was further increased by 29% through n-hexane-rinsing post-interfacial polymerization. Thus, this simple yet effective combination of heat-pressing and hydrolysis presents a promising approach for developing high-performance thin-film nanocomposite (TFNC) membranes.
PubMed: 38475394
DOI: 10.3390/polym16050713 -
Gels (Basel, Switzerland) Feb 2024Accurate dosimetric verification is becoming increasingly important in radiotherapy. Although polymer gel dosimetry may be useful for verifying complex 3D dose...
Accurate dosimetric verification is becoming increasingly important in radiotherapy. Although polymer gel dosimetry may be useful for verifying complex 3D dose distributions, it has limitations for clinical application due to its strong reactivity with oxygen and other contaminants. Therefore, it is important that the material of the gel storage container blocks reaction with external contaminants. In this study, we tested the effect of air and the chemical permeability of various polymer-based 3D printing materials that can be used as gel containers. A methacrylic acid, gelatin, and tetrakis (hydroxymethyl) phosphonium chloride gel was used. Five types of printing materials that can be applied to the fused deposition modeling (FDM)-type 3D printer were compared: acrylonitrile butadiene styrene (ABS), co-polyester (CPE), polycarbonate (PC), polylactic acid (PLA), and polypropylene (PP) (reference: glass vial). The map of R2 (1/T2) relaxation rates for each material, obtained from magnetic resonance imaging scans, was analyzed. Additionally, response histograms and dose calibration curves from the R2 map were evaluated. The R2 distribution showed that CPE had sharper boundaries than the other materials, and the profile gradient of CPE was also closest to the reference vial. Histograms and dose calibration showed that CPE provided the most homogeneous and the highest relative response of 83.5%, with 8.6% root mean square error, compared with the reference vial. These results indicate that CPE is a reasonable material for the FDM-type 3D printing gel container.
PubMed: 38391476
DOI: 10.3390/gels10020146 -
Scientific Reports Oct 2023An efficient synthesis of 5-substituted 1H-tetrazoles was successfully achieved through one-pot multi-component condensation reactions of some aromatic aldehydes or...
One-pot synthesis, computational chemical study, molecular docking, biological study, and in silico prediction ADME/pharmacokinetics properties of 5-substituted 1H-tetrazole derivatives.
An efficient synthesis of 5-substituted 1H-tetrazoles was successfully achieved through one-pot multi-component condensation reactions of some aromatic aldehydes or indolin-2,3-dione with malononitrile and sodium azide using diverse reaction conditions to obtain considerable product yields. Furthermore, it has been achieved for the first time to construct desired products under neat condition. Molecular docking studies with CSNK2A1 receptor disclosed the lowest binding energy displayed by the dimethoxyphenyl derivative 4c with - 6.8687 kcal/mol. The synthesized tetrazoles were screened for their in-vitro cytotoxic activity against epidermoid cancer cell line (A431) and colon cancer line (HCT116) with respect to normal skin fibroblast cell line (BJ-1) using MTT assay, and antimicrobial activity against the bacteria: K. pneumonia, S. aureus, and the fungi: Candida albicans, as well as their antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl assay. In addition, the toxicity of tetrazole derivative was assessed by determination of their approximate lethal dose fifty (LD), calculated via an oral administration to rats, through measurement of ALT and bilirubin levels in serum. The antitumor results can suggest that the potent tetrazole derivative namely, 3-(3,4-dimethoxyphenyl)-2-(1H-tetrazol-5-yl)acrylonitrile (4c) could be a potential drug against epidermoid carcinoma. The antioxidant results indicated to tetrazoles exhibited great antioxidant properties even at very low doses. A molecular dynamics simulation was performed for the synthesized compounds (ligands) to investigate their tendency for binding with the active sites of protein.
Topics: Animals; Rats; Molecular Docking Simulation; Antioxidants; Staphylococcus aureus; Tetrazoles; Structure-Activity Relationship; Molecular Structure
PubMed: 37857636
DOI: 10.1038/s41598-023-44615-4 -
International Journal of Molecular... May 2024Recently, a compound derived from recent scientific advances named has emerged as the focus of this research, the aim of which is to explore its potential impact on...
Recently, a compound derived from recent scientific advances named has emerged as the focus of this research, the aim of which is to explore its potential impact on solid tumor cell lines. Using a combination of bioinformatics and biological assays, this study conducted an in-depth investigation of the effects of . The results of this study have substantial implications for cancer research and treatment. has shown remarkable efficacy in inhibiting the growth of several cancer cell lines, including those representing prostate carcinoma (PC3) and cervical carcinoma (HeLa). The high sensitivity of these cells, indicated by low IC values, underscores its potential as a promising chemotherapeutic agent. In addition, has revealed the ability to induce cell cycle arrest, particularly in the G2/M phase, a phenomenon with critical implications for tumor initiation and growth. By interfering with DNA replication in cancer cells, has shown the capacity to trigger cell death, offering a new avenue for cancer treatment. In addition, computational analyses have identified key genes affected by treatment, suggesting potential therapeutic targets. These genes are involved in critical biological processes, including cell cycle regulation, DNA replication and microtubule dynamics, all of which are central to cancer development and progression. In conclusion, this study highlights the different mechanisms of that inhibit cancer cell growth and alter the cell cycle. These promising results suggest the potential for more effective and less toxic anticancer therapies. Further in vivo validation and exploration of combination therapies are critical to improve cancer treatment outcomes.
Topics: Humans; Microtubules; Antineoplastic Agents; Cell Line, Tumor; Acrylonitrile; Cell Proliferation; Neoplasms; HeLa Cells; Apoptosis; Triazoles; Cell Cycle Checkpoints; Tubulin Modulators; PC-3 Cells
PubMed: 38891892
DOI: 10.3390/ijms25115704