Discover Materials最新文献

Tribological and antibacterial behavior of Cu doped DLC coatings for biomedical implants. 生物医学植入物中Cu掺杂DLC涂层的摩擦学和抗菌性能。

IF 5.1

Discover Materials Pub Date : 2026-01-01 Epub Date: 2026-03-14 DOI: 10.1007/s43939-026-00628-0

Ayowolemiwa Victor Towobola, Amal George, Tonye Alaso Jack, Jenny-Lee Thomassin, Qiaoqin Yang

{"title":"Tribological and antibacterial behavior of Cu doped DLC coatings for biomedical implants.","authors":"Ayowolemiwa Victor Towobola, Amal George, Tonye Alaso Jack, Jenny-Lee Thomassin, Qiaoqin Yang","doi":"10.1007/s43939-026-00628-0","DOIUrl":"https://doi.org/10.1007/s43939-026-00628-0","url":null,"abstract":"Cu-DLC coatings were deposited on CoCrMo alloys and silicon wafers using magnetron sputtering. Increasing the atomic percentage (at%) of Cu incorporated into the DLC coatings did not significantly alter their overall structure. However, X-ray diffraction results revealed structural differences with increasing Cu content, including larger crystallite sizes and a transition from a predominantly amorphous structure to a nanocrystalline phase. Significant changes in chemical bonding states were observed through Raman and X-ray photoelectron spectroscopy (XPS). Nanoindentation analysis showed reductions in both hardness and elastic modulus, which were inversely correlated with increasing Cu content. Moreover, the wear rate of Cu-DLC showed a greater decrease at 11.8 at% Cu compared to the other coating. Corrosion analysis further indicated that higher Cu content moderated the corrosion inhibition rate. Time course bacterial killing assays demonstrated that Cu contents between 11 and 15.2 at% in the DLC coatings effectively killed both Staphylococcus aureus and multi-drug resistant Klebsiella pneumoniae, with the highest Cu at% resulting in complete bacterial killing at all time points. Overall, incorporation of Cu into DLC coatings enhances corrosion and antibacterial activity with reduced mechanical integrity. An optimal balance between mechanical integrity and antibacterial function can be achieved by carefully controlling the amount of Cu incorporated into the DLC coatings.","PeriodicalId":34625,"journal":{"name":"Discover Materials","volume":"6 1","pages":"148"},"PeriodicalIF":5.1,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13099718/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147783468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Zero temperature coefficient microwave alumina ceramics via TiO₂ doping and post sinter annealing 采用tio2掺杂和烧结后退火工艺制备零温度系数微波氧化铝陶瓷

Discover Materials Pub Date : 2025-11-17 DOI: 10.1007/s43939-025-00429-x

Yuting Xiao, Millicent Appiah, Burhan Ullah, Yixing Yang, Wayne D. Kaplan, Daniel Q. Tan

{"title":"Zero temperature coefficient microwave alumina ceramics via TiO₂ doping and post sinter annealing","authors":"Yuting Xiao, Millicent Appiah, Burhan Ullah, Yixing Yang, Wayne D. Kaplan, Daniel Q. Tan","doi":"10.1007/s43939-025-00429-x","DOIUrl":"https://doi.org/10.1007/s43939-025-00429-x","url":null,"abstract":"Alumina (Al₂O₃) is a promising candidate for microwave dielectric ceramics due to its exceptional quality factor (Qf ~ 333,000 GHz). This study investigates the influence of additions of titania (TiO₂) and annealing treatments on the dielectric properties of polycrystalline Al₂O₃. The dielectric properties of Al₂O₃-x wt% TiO₂ (x = 2.5, 5, 7.5, 10) were evaluated after various heat treatment conditions. The optimal composition, Al₂O₃-7.5 wt% TiO₂, achieved notable properties when sintered at 1400 °C for 8 h: a relative permittivity (εr) of 10.73 and a quality factor-frequency product (Qf) of 126,347 GHz at 13.814 GHz. Specifically, subsequent annealing at 1000 °C for 5 h adjusted the temperature coefficient of frequency ( $$:{tau}_{f}$$ ) to + 1.25 ppm/°C, near zero. The study reveals that the thermal treatment induces the decomposition of Al₂TiO₅ into Al₂O₃ and TiO₂, accompanied by titanium redistribution. Characterization using X-ray diffraction, scanning electron microscopy, differential scanning calorimetry, and dielectric measurements established correlations between the microstructure and properties. This work provides a scalable framework for designing ultra-stable millimeter-wave ceramics, particularly for 5G/6G resonators and satellite communication systems, where minimal signal delay and thermal drift are critical.","PeriodicalId":34625,"journal":{"name":"Discover Materials","volume":"5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s43939-025-00429-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147331138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

In-situ microscopy and digital image correlation to study the mechanical characteristics of polymer-based materials. 原位显微镜和数字图像相关研究聚合物基材料的力学特性。

Discover Materials Pub Date : 2025-01-01 Epub Date: 2025-02-18 DOI: 10.1007/s43939-025-00208-8

Seyedtaghi Mousavi, John G Hardy

引用次数: 0

Transdermal microneedle patch for antioxidants release. 抗氧化剂释放透皮微针贴片。

Discover Materials Pub Date : 2025-01-01 Epub Date: 2025-03-22 DOI: 10.1007/s43939-025-00240-8

Samuel Mugo, Scott Robertson, Weihao Lu

{"title":"Transdermal microneedle patch for antioxidants release.","authors":"Samuel Mugo, Scott Robertson, Weihao Lu","doi":"10.1007/s43939-025-00240-8","DOIUrl":"10.1007/s43939-025-00240-8","url":null,"abstract":"Polymer based microneedle transdermal drug delivery system fits the criterion for an efficient patient compliant drug delivery system of the future. Smart and controlled microneedle drug delivery systems remain an emerging research area. One of the objectives of this study was to design an accessible approach of molding microneedles using a beeswax mold. The second objective was to evaluate a polymer-based microneedle drug release transdermal platform fabricated via layer by layer (LbL) assembly of conductive polydimethylsiloxane integrated with carbon nanotubes, cellulose nanocrystal and polyaniline (PDMS@CNT/CNC@PANI). The electrically conductive PDMS@CNT/CNC@PANI microneedle patch provides a platform for drug loading, stabilization and transdermal controlled drug release. The drug loaded PDMS@CNT/CNC@PANI microneedle patch was evaluated for diffusion and voltage mediated transdermal delivery of thymol blue and rutin as model compounds. Chicken skin was used as an analogue of human skin. Both electrochemical and passive release from the rutin loaded PDMS@CNC/CNT microneedle patch resulted in ~ 66%. On the other hand, the PDMS@CNC/CNT@PANI patch loaded with rutin resulted in 66-84% release. The results show the novel microneedle patches could effectively release rutin in a controlled manner, and as such showed promise for potential use in clinical drug release applications.Graphical abstract: Supplementary information: The online version contains supplementary material available at 10.1007/s43939-025-00240-8.","PeriodicalId":34625,"journal":{"name":"Discover Materials","volume":"5 1","pages":"64"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11929698/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143701701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Microstructural analysis and densification of ordinary Portland cement mortars incorporated with minimal nano-TiO2: intermixing and surface coating on both fresh and hardened surfaces 掺入极少量纳米二氧化钛的普通硅酸盐水泥砂浆的微观结构分析和致密化：新拌和物和硬化表面的表面涂层

Discover Materials Pub Date : 2024-07-24 DOI: 10.1007/s43939-024-00096-4

N. A. Reddy, P. S. Chandana