Frontiers in Materials最新文献

{"title":"Shaping ability of ProTaper Ultimate and BlueShaper in mandibular molars: a micro-CT evaluation","authors":"Katia Greco, Francesco Iacono, Francesco Montagna, Carola Esposito Corcione, Gaetano Paolone, Enrico Gherlone, Giuseppe Cantatore","doi":"10.3389/fmats.2024.1363835","DOIUrl":"https://doi.org/10.3389/fmats.2024.1363835","url":null,"abstract":"Aim: The study aimed to evaluate the shaping characteristics of ProTaper Ultimate (Dentsply Sirona) and BlueShaper (Zarc4Endo) using microcomputed tomographic imaging technology (micro-CT).Methods: Thirty mesial and distal canals of extracted second mandibular molars with similar anatomy were selected and scanned pre- and postoperatively by micro-CT scanning (SkyScan 1172, Bruker micro-CT) with a voxel size of 11 μm and shaped with two different procedures: ProTaper Ultimate (Group 1: n = 15) and BlueShaper (Group 2: n = 15) were used following the manufacturer’s recommendations up to final 30 apical size. Irrigation was ensured in all groups with 5.25% NaOCl and 10% EDTA during instrumentation. Canal transportation, the volume of removed dentin, and area of untreated surface were matched with preoperative values with Bruker CT Analyser (Bruker micro-CT). Data were statistically analyzed using Student’s t-test.Results: No significant differences were observed between Group 1 and Group 2 in terms of canal transportation, volume of removed dentin, and untreated surfaces. A significant difference (<jats:italic>p</jats:italic> &amp;lt; 0.05) in the amount of untreated surfaces was found between the mesial and distal canals in both groups.Conclusion: Shaping procedures with both ProTaper Ultimate and BlueShaper demonstrated similar canal enlargement volumes and similar canal transportation without evidence of significant preparation errors. Nevertheless, a high amount of untreated surface was reported for both systems, particularly in distal canals.","PeriodicalId":12524,"journal":{"name":"Frontiers in Materials","volume":"50 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140570738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Mg incorporation on the properties of PCL/Mg composites for potential tissue engineering applications","authors":"Sumama Nuthana Kalva, Fawad Ali, Kripa Subhadra Keyan, Omar M. Khan, Mujaheed Pasha, Carlos A. Velasquez, Muammer Koç","doi":"10.3389/fmats.2024.1294811","DOIUrl":"https://doi.org/10.3389/fmats.2024.1294811","url":null,"abstract":"Polycaprolactone (PCL) is a biocompatible polymer readily moldable into various shapes and designs. However, its low mechanical strength and slow biodegradation restrict its use in tissue engineering. Magnesium (Mg), a biocompatible metal with excellent osteoconductivity and biodegradability, is a promising choice for tissue engineering applications. This study investigates the influence of Mg incorporation on the properties of PCL/Mg composites, aiming to evaluate their suitability for 3D-printable (3DP) tissue engineering applications. We synthesized a series of PCL/Mg composites with varying Mg concentrations and characterized their mechanical, thermal, and degradation properties. According to microscopic analysis of the composite films, the Mg particles are dispersed consistently throughout all the compositions. The findings demonstrated that adding Mg influenced PCL’s mechanical and thermal properties. The mechanical test results showed that the tensile strength of 15% Mg composite filaments improved by around 10% compared to the neat PCL filaments. However, the elastic modulus decreased by around 50% for the same composition. The thermal study revealed a significant reduction in the degradation temperature from above 400°C for pure PCL to around 300°C for PCL/Mg composite having 15% Mg. Additionally, the weight loss during <jats:italic>in vitro</jats:italic> degradation showed that the presence of Mg had significantly increased the degradation rate of composite samples. Also, Mg incorporation influences cell adhesion, with better attachment observed for 10% Mg 3DP samples. Overall, PCL/Mg composites offer a solution to overcome the limitation of low thermo-mechanical properties typically associated with the PCL.","PeriodicalId":12524,"journal":{"name":"Frontiers in Materials","volume":"123 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140570655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tensile properties and constitutive model of cost-effective multiscale hybrid fiber reinforced strain hardening cementitious composites","authors":"Jin Hou, Jianjun Bai, Hongmei Mou, Zhisuo Xiang","doi":"10.3389/fmats.2024.1378089","DOIUrl":"https://doi.org/10.3389/fmats.2024.1378089","url":null,"abstract":"To enhance the mechanical properties and cost-effectiveness of conventional polyvinyl alcohol fiber reinforced strain hardening cementitious composite (PVA-SHCC), a modified version called multiscale hybrid fiber reinforced SHCC (MsHySHCC) was developed. This new composite incorporates a combination of steel fiber, PVA fiber and calcium carbonate (CaCO<jats:sub>3</jats:sub>) whisker. Uniaxial direct tensile behaviors (stress-strain relationship, tensile strength, tensile deformation capacity and tensile toughness) of designed MsHySHCCs were investigated and evaluated. The results show that the PVA fibers dominate the ductile behavior and the steel fibers and CaCO<jats:sub>3</jats:sub> whiskers effectively affect the strength of MsHySHCCs. The PVA fibers can be partially replaced by CaCO<jats:sub>3</jats:sub> whisker and steel fiber, along with an increase in tensile strength and ductility of designed composites. The findings suggest that the configuration of MsHySHCC proves to be a viable approach in simultaneously enhancing the strength and ductility of PVA-SHCC. A semi-theoretical prediction model for tensile constitutive relationship was derived. The comparison of the theoretical results with the experimental data shows that this semi-theoretical model is applicable for determining the tensile constitutive relationship of PVA-SHCCs and MsHySHCCs.","PeriodicalId":12524,"journal":{"name":"Frontiers in Materials","volume":"55 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140603204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical properties and hydration mechanism of super-sulfated cement prepared with ordinary Portland cement, carbide slag, and sodium silicate","authors":"Guangzheng Qi, Qiang Zhang, Zhengning Sun","doi":"10.3389/fmats.2024.1406045","DOIUrl":"https://doi.org/10.3389/fmats.2024.1406045","url":null,"abstract":"Super-sulfated cement (SSC) is known for its low-carbon footprint, energy efficiency, and eco-friendliness (mainly derived from industrial by-products) with promising applications. However, SSC’s slow early strength development results in inadequate initial hardening, compromising its durability and limiting its use in practical engineering projects. This study aims to enhance SSC’s early performance by incorporating ordinary Portland cement (OPC), carbide slag (CS), and sodium silicate as alkaline activators alongside anhydrite. The effects of varying proportions of OPC, CS, and sodium silicate on SSC’s compressive strength and hydration mechanism have been investigated experimentally in this study. Results show that using 2% OPC, 2% CS, and 1% sodium silicate as alkaline activators effectively activates slag hydration in SSC-2, achieving a compressive strength of 9.6 MPa at 1 day of hydration. As hydration progresses, SSC’s compressive strength continues to increase. In the early hydration stage, OPC and CS create an alkaline environment for SSC, facilitating rapid slag reaction with anhydrite and sodium silicate, resulting in ettringite and C–S–H formation. Simultaneously, slag hydration produces C–S–H and OH-hydrotalcite, filling voids in the ettringite-formed skeleton structure, leading to a denser microstructure and significantly enhancing SSC’s early compressive strength. From 28 to 90 days of hydration, the ettringite formation rate decreases in the SSC system, but some anhydrite remains, while C–S–H production continues to rise, further enhancing late-stage compressive strength.","PeriodicalId":12524,"journal":{"name":"Frontiers in Materials","volume":"122 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140613626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design of novel microstrip patch antenna for millimeter-wave B5G communications","authors":"Jun Jiat Tiang, Deema Mohammed Alsekait, Imran Khan, Pi-Chung Wang, Dag Øivind Madsen","doi":"10.3389/fmats.2024.1364159","DOIUrl":"https://doi.org/10.3389/fmats.2024.1364159","url":null,"abstract":"Introduction: The simplicity of integration and co-type features of microstrip antennas make them intriguing for a broad variety of applications, particularly with the growing usage of mmWave bands in wireless communications and the constant rise in data transfer in communication situations.Method: This paper proposes a novel design of micrstrip patch antenna for mmWave B5G communication. The main idea is to realize four-mode antenna the operates in four different frequencies. The geometry is rectangular patch whose resonance frequency is adjusted by varying the walls and pins of the structure.Results: Simulation results show that the proposed antenna design has improved fractional bandwidth and performance as compared with existing antennas.Discussion: The observed curve indicates that, in agreement with the modeling findings, there are four resonance spots in the operational frequency region of 2.5–3.4 GHz: 2.68 GHz, 2.9 GHz, 3.05 GHz, and 3.3 GHz, which correspond to TM1/2,0, TM3/2,0, and TMRS, respectively, and TM1/2,2 four resonant modes, within the frequency range, the observed antenna gain peak is around 9 dBi, which is consistent with the measured results.","PeriodicalId":12524,"journal":{"name":"Frontiers in Materials","volume":"118 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140570728","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"D-amino acid/gentamicin loaded zwitterionic hydrogel coatings with optimized mechanical stability and biofilm inhibition capabilities","authors":"Jingzhi Yang, Yami Ran, Junsen Zhao, Taiwei Xing, Xiangping Hao, Dawei Zhang","doi":"10.3389/fmats.2024.1371351","DOIUrl":"https://doi.org/10.3389/fmats.2024.1371351","url":null,"abstract":"Biofilms associated bacterial infections on material surfaces have become a tremendous biomedical challenge. Developing antimicrobial coatings on biomaterial surfaces and endowing them with decent mechanical stability and biofilm inhibition capabilities is an efficient way to resist bacterial attachment and biofilm formation. Herein, we integrated 2-hydroxyethyl methacrylate (HEMA) and D-amino acid mixtures based antibiofilm combinations with sulfobetaine methacrylate (SBMA) hydrogel coatings. The obtained hydrogel coatings demonstrated high stability in various transport and service environments. The proper incorporation of the HEMA achieves only ∼3% weight loss of SBMA hydrogel coatings after swelling, flushing and abrasion damages. In addition, both biofilm formation inhibiting D-amino acid mixtures and bacteria-killing gentamicin components were loaded in the coatings. The synergistic action of these two components was able to significantly reduce the bacterial numbers with up to 2.3 log reduction. The bacteria exposed to D-amino acid mixtures was difficult to form biofilm, which was more susceptive to the harm of gentamicin. This work provides an effective paradigm to integrate mechanically stable SBMA-HEMA hydrogel with natural D-amino acid mixtures based antibiofilm agents to generate biomedical surfaces to combat biofilms associated bacterial infections.","PeriodicalId":12524,"journal":{"name":"Frontiers in Materials","volume":"206 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140570888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Highly defective NiFeV layered triple hydroxide with enhanced electrocatalytic activity and stability for oxygen evolution reaction","authors":"Xi-Yuan Li, Lin-Cheng Xu, Yue Wang, Yong Yan, Ying-Jie Feng, Fan Li","doi":"10.3389/fmats.2024.1388695","DOIUrl":"https://doi.org/10.3389/fmats.2024.1388695","url":null,"abstract":"Oxygen evolution reaction (OER) is one of the most important components of various electrochemical systems such as water splitting, metal air batteries, and carbon dioxide reduction. However, the four-electron process of OER suffers from intrinsically sluggish kinetics, which contributes to significant overpotential in the electrochemical system. Herein, highly defective NiFeV layered triple hydroxide (LTH) catalyst was efficiently prepared using a one-step hydrothermal method. The crystal structure, electronic structure, and surface composition of NiFeV LTH were characterized by X-ray diffraction and photoelectron spectroscopy. Moreover, NiFeV LTH demonstrated a superior OER catalytic performance with-low overpotential (158 mV @10 mA·cm-2), related small Tafel slope (102.3 mV·dec−1), and long-term stability at a high current density of 100 mA·cm-2. In situ Raman spectroscopy was applied to investigate the surface reconstruction during the OER process. It is revealed that Ni species were the most active sites at low overpotential, with the potential increasing subsequently Fe and V gradually participates in the catalytic reaction, the Fe and Ni species as OER catalytic active sites lead to the excellent OER catalytic activity of NiFeV LTH, and inhibited the further dissolution of high-valence NiOOH at high overpotential. The mechanism induced the outstanding activity and stability at high current densities in NiFeV LTH system. Dissolution of vanadium excited the active sites of NiFeV LTH synthesized by hydrothermal method which promoted both activity and stability, while the changes of surface species at different OER potentials were detected by in situ Raman spectroscopy.","PeriodicalId":12524,"journal":{"name":"Frontiers in Materials","volume":"39 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140614019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synergy effect of polyaspartic acid and D-phenylalanine on corrosion inhibition caused by Desulfovibrio vulgaris","authors":"Bo Pang, Hongyi Li, Chengcheng Ding, Chao Song, Shuguang Wang","doi":"10.3389/fmats.2024.1390242","DOIUrl":"https://doi.org/10.3389/fmats.2024.1390242","url":null,"abstract":"Microbiologically influenced corrosion (MIC) poses a threat to various fields, particularly in piping and cooling water systems. As a green corrosion inhibitor, polyaspartic acid (PASP) faces challenges in achieving the intended corrosion inhibition against MIC due to biofilm. Therefore, mitigating biofilm might be the key to improving the corrosion inhibition of PASP. D-Phenylalanine (D-Phe) was selected as an enhancer to promote the inhibition of PASP on MIC caused by <jats:italic>Desulfovibrio vulgaris</jats:italic> due to its potential role in biofilm formation in this work. The joint application of PASP and D-Phe reduced the corrosion rate by 76.54% and obviously decreased the depth of corrosion pits with the maximum depth at 0.95 µm. Also, fewer cells adhered to the coupon surface due to the combined action of PASP and D-Phe, leading to thin and loose biofilm. Besides, both cathodic and anodic reactions were retarded with PASP and D-Phe, resulting in a low corrosion current at 0.530 × 10<jats:sup>−7</jats:sup> A/cm<jats:sup>2</jats:sup>. The primary synergy mechanism is that D-Phe promoted the formation of PASP protective film via decreasing bacterial adhesion and thus inhibited electrochemical reaction and electron utilization of cells from metal surface. This study introduces a novel strategy to augment the effectiveness of PASP in inhibiting MIC.","PeriodicalId":12524,"journal":{"name":"Frontiers in Materials","volume":"9 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140570849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Understanding the high-temperature corrosion behavior of zirconium alloy as cladding tubes: a review","authors":"Yan Tang, Jingjing Liao, Di Yun","doi":"10.3389/fmats.2024.1381818","DOIUrl":"https://doi.org/10.3389/fmats.2024.1381818","url":null,"abstract":"Operated under extreme conditions, corrosion occurs between zirconium alloy cladding tubes and the coolant in the primary loop of pressurized water reactors (PWRs), contributing to a reduction in the effective metallic material thickness. Therefore, understanding the corrosion behavior of zirconium alloy is vital to both raising the burnup of PWR and the improvement of safety properties of these reactors. During the past decades, extensive investigation was conducted with various conditions, such as changing corrosion temperatures and alloying elements, but contradiction persists and universal conclusion remain elusive. In the present work, a variety of research results that focused on corrosion kinetics, microstructural evolution, and the influence of alloying elements were integrated and summarized, so that a valuable reference can be provided to further research.","PeriodicalId":12524,"journal":{"name":"Frontiers in Materials","volume":"79 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140603230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Narrowing of band gap and decrease in dielectric loss in La1-xSrxMnO3 for x = 0.0, 0.1, and 0.2 manganite nanoparticles","authors":"Akhtar Ali, Wiqar H. Shah, Zakir Ullah, Shaheryar Malik, Muhammad Rauf, Sameh Askar, Naveed Imran, Hijaz Ahmad","doi":"10.3389/fmats.2024.1369122","DOIUrl":"https://doi.org/10.3389/fmats.2024.1369122","url":null,"abstract":"Polycrystalline compounds of lanthanum strontium manganite (La<jats:sub>1-<jats:italic>x</jats:italic></jats:sub>Sr<jats:sub><jats:italic>x</jats:italic></jats:sub>MnO<jats:sub>3</jats:sub>, LSMO) are widely used in electronic storage devices due to their minimal losses and electronic charge transport properties. In this study, we investigated how varying substitutions of Sr<jats:sup>2+</jats:sup> for values of <jats:italic>x</jats:italic> = 0.0, 0.1, and 0.2 affected the tuning of the optical band gap and dielectric losses in La<jats:sub>1-<jats:italic>x</jats:italic></jats:sub>Sr<jats:sub><jats:italic>x</jats:italic></jats:sub>MnO<jats:sub>3</jats:sub> nanoparticles. Synthesized samples were structurally analyzed via X-ray diffraction. A rhombohedral <jats:italic>R</jats:italic><jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mrow><mml:mover accent=\"true\"><mml:mn>3</mml:mn><mml:mo>¯</mml:mo></mml:mover><mml:mi>c</mml:mi><mml:mtext> crystal</mml:mtext></mml:mrow></mml:math></jats:inline-formula> structure was confirmed for all prepared samples; crystallite size ranging from 15 nm to 20 nm was estimated along with other lattice parameters. Polygonal or hexagonal-like morphology was revealed by field emission scanning electron microscopy, with a moderate size distribution of nanoparticles affected by thinner grain boundaries in doped LSMO. Energy dispersive spectroscopy was employed to confirm the elemental composition of each compound, and the infrared spectrum indicated bonding in the fingerprint region It was observed that there was a significant reduction in the optical band gap, which was measured using ultraviolet spectrometer absorption data. The band gap decreased from 4.34 eV to 4.11 eV. This reduction was found to be related to the difference in refractive index, which was calculated using both Moss and Herve–Vandamme relations. In parallel, frequency-dependent dielectric analysis revealed that frequency was proportional to the increase in Sr content, inversely affecting dielectric loss. Moreover, the AC conductivity of the prepared samples increased with the rise in Sr content, as described by Johnscher’s universal power law in the region of high frequency.","PeriodicalId":12524,"journal":{"name":"Frontiers in Materials","volume":"25 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140303312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}