Pub Date : 2024-07-30DOI: 10.3389/fmats.2024.1438660
Chenyang Niu, Dongwen Li, Yujia Zhang, Yunkai Wang, Shangbo Ning, Gang Zhao, Zhihui Ye, Yu Kong, Donghong Yang
Clear aligner therapy is a rapidly developing orthodontic treatment. 3D-printing technology, which enables the creation of complex geometric structures with high precision, has been used in dentistry. This article aims to summarize the various aspects of 3D-printing clear aligners and give an outlook on their future development. The traditional thermoforming technology is introduced and the principle and application of 3D-printed clear aligners and materials are introduced, as well as the application prospects of 3D-printed clear aligners. According to PRISMA statement, the relevant literature of 3D-printing clear aligner was searched in PubMed, Web of Science, Embase and other databases. We searched the related words in the MESH database and then carried out advanced searches. We read systematic review and conference papers to find the articles related to the subject and manually added and excluded articles by reading the title and abstract. The production of clear aligners combines computer-aided 3D analysis, personalized design and digital molding technology. The thickness and edges of the 3D-printed clear aligner can be digitally controlled, which allows appliance more efficiently fitted. Presently, the array of clear resins suitable for 3D-printing include photo polymeric clear methacrylate-based resin (Dental LT) (Form Labs, Somerville, Mass), aliphatic vinyl ester-polyurethane polymer (Tera Harz TC-85) (Graphy, Seoul, South Korea). They all have good biocompatibility. But no such material is currently approved on the market. Developing biocompatible resins and further improving the material’s mechanical properties will be critical for the combination of 3D-printing and clear aligners. However, the literature on 3D-printed clear aligners is limited and lacks clinical application. Further in vivo and in vitro tests, as well as additional exploration in conjunction with corresponding cytological tests, are required for the research on available materials and machinery for 3D-printing clear aligners.
透明矫治器疗法是一种发展迅速的正畸治疗方法。三维打印技术可以高精度地创建复杂的几何结构,目前已被应用于牙科领域。本文旨在总结3D打印透明矫治器的各个方面,并对其未来发展进行展望。在介绍传统热成型技术的基础上,介绍了3D打印透明矫治器的原理、应用和材料,以及3D打印透明矫治器的应用前景。根据PRISMA声明,在PubMed、Web of Science、Embase等数据库中检索了3D打印透明对齐器的相关文献。我们在 MESH 数据库中检索了相关词,然后进行了高级检索。我们阅读了系统综述和会议论文,找到了与主题相关的文章,并通过阅读标题和摘要手动添加和排除了文章。透明矫治器的生产结合了计算机辅助三维分析、个性化设计和数字成型技术。三维打印透明矫治器的厚度和边缘可以通过数字控制,从而使矫治器更有效地安装。目前,适合三维打印的透明树脂包括光聚合物甲基丙烯酸酯基透明树脂(Dental LT)(Form Labs, Somerville, Mass)、脂肪族乙烯基酯-聚氨酯聚合物(Tera Harz TC-85)(Graphy, Seoul, South Korea)。它们都具有良好的生物相容性。但目前市场上还没有此类材料获得批准。开发生物相容性树脂并进一步提高材料的机械性能,对于 3D 打印和透明对齐器的结合至关重要。然而,有关3D打印透明矫治器的文献资料非常有限,而且缺乏临床应用。需要进一步进行体内和体外测试,并结合相应的细胞学测试进行更多探索,以研究用于三维打印透明对齐器的可用材料和机械。
{"title":"Prospects for 3D-printing of clear aligners—a narrative review","authors":"Chenyang Niu, Dongwen Li, Yujia Zhang, Yunkai Wang, Shangbo Ning, Gang Zhao, Zhihui Ye, Yu Kong, Donghong Yang","doi":"10.3389/fmats.2024.1438660","DOIUrl":"https://doi.org/10.3389/fmats.2024.1438660","url":null,"abstract":"Clear aligner therapy is a rapidly developing orthodontic treatment. 3D-printing technology, which enables the creation of complex geometric structures with high precision, has been used in dentistry. This article aims to summarize the various aspects of 3D-printing clear aligners and give an outlook on their future development. The traditional thermoforming technology is introduced and the principle and application of 3D-printed clear aligners and materials are introduced, as well as the application prospects of 3D-printed clear aligners. According to PRISMA statement, the relevant literature of 3D-printing clear aligner was searched in PubMed, Web of Science, Embase and other databases. We searched the related words in the MESH database and then carried out advanced searches. We read systematic review and conference papers to find the articles related to the subject and manually added and excluded articles by reading the title and abstract. The production of clear aligners combines computer-aided 3D analysis, personalized design and digital molding technology. The thickness and edges of the 3D-printed clear aligner can be digitally controlled, which allows appliance more efficiently fitted. Presently, the array of clear resins suitable for 3D-printing include photo polymeric clear methacrylate-based resin (Dental LT) (Form Labs, Somerville, Mass), aliphatic vinyl ester-polyurethane polymer (Tera Harz TC-85) (Graphy, Seoul, South Korea). They all have good biocompatibility. But no such material is currently approved on the market. Developing biocompatible resins and further improving the material’s mechanical properties will be critical for the combination of 3D-printing and clear aligners. However, the literature on 3D-printed clear aligners is limited and lacks clinical application. Further <jats:italic>in vivo</jats:italic> and <jats:italic>in vitro</jats:italic> tests, as well as additional exploration in conjunction with corresponding cytological tests, are required for the research on available materials and machinery for 3D-printing clear aligners.","PeriodicalId":12524,"journal":{"name":"Frontiers in Materials","volume":"47 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141866991","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}
Pub Date : 2024-07-30DOI: 10.3389/fmats.2024.1420014
Awen Bruneau, François Mahé, Christophe Binetruy, Sébastien Comas-Cardona, Charlotte Landry, Nelly Durand
A numerical model of packing applied to rigid objects is presented. It aims at describing a random stack of polymer composite chips in order to model the packing step of an existing recycling technique. The geometric properties of the stack play a major role in the mechanical properties of the recycled products. Short, simple and effective geometric descriptors of the stack are proposed. Their ability to differentiate random stacks is illustrated with an example. Then, a validation is proposed based on experimental data obtained from a bench specially designed for this work. The tests consist in the free fall of square chips. Finally, the developed model is compared to other models (free fall and packing of fibers) in order to enforce its relevance in the simulation of packing of rigid objects.
{"title":"Packing simulation and analysis applied to a thermoplastic composite recycling process","authors":"Awen Bruneau, François Mahé, Christophe Binetruy, Sébastien Comas-Cardona, Charlotte Landry, Nelly Durand","doi":"10.3389/fmats.2024.1420014","DOIUrl":"https://doi.org/10.3389/fmats.2024.1420014","url":null,"abstract":"A numerical model of packing applied to rigid objects is presented. It aims at describing a random stack of polymer composite chips in order to model the packing step of an existing recycling technique. The geometric properties of the stack play a major role in the mechanical properties of the recycled products. Short, simple and effective geometric descriptors of the stack are proposed. Their ability to differentiate random stacks is illustrated with an example. Then, a validation is proposed based on experimental data obtained from a bench specially designed for this work. The tests consist in the free fall of square chips. Finally, the developed model is compared to other models (free fall and packing of fibers) in order to enforce its relevance in the simulation of packing of rigid objects.","PeriodicalId":12524,"journal":{"name":"Frontiers in Materials","volume":"50 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141867087","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}
Pub Date : 2024-07-30DOI: 10.3389/fmats.2024.1397937
Daniel Wyn Müller, Ben Josten, Sebastian Wältermann, Christoph Pauly, Sebastian Slawik, Kristina Brix, Ralf Kautenburger, Frank Mücklich
Introduction: Topographic surface patterning in the micro- and nanometer scale has evolved into a well applied approach in surface functionalization following biomimetic blueprints from nature. Depending on the production process an additional impact of process-related substrate modification has to be considered in functional surface optimization. This is especially true in case of antimicrobial applications of Cu surfaces where a modification of the substrate properties might impact bactericidal efficiency.Methods: In this regard, the effect of ultrashort pulsed direct laser interference patterning on the microstructure of pure Cu and resulting antimicrobial properties was investigated alongside line-like patterning in the scale of single bacterial cells.Results and Discussion: The process-induced microstructure modification was shown to play an important role in corrosion processes on Cu surfaces in saline environment, whereas the superficial microstructure impacts both corrosive interaction and ion emission. Surprisingly, antimicrobial efficiency is not predominantly following deviating trends in Cu ion release rates but rather depends on surface topography and wettability, which was shown to be impacted by the substrate microstructure state, as well. This highlights the need of an in-depth understanding on how different surface properties are simultaneously modulated during laser processing and how their interaction has to be designed to acquire an effective surface optimization e.g., to agitate active antimicrobial surface functionalization.
{"title":"Microstructure versus topography: the impact of crystallographic substrate modification during ultrashort pulsed direct laser interference patterning on the antibacterial properties of Cu","authors":"Daniel Wyn Müller, Ben Josten, Sebastian Wältermann, Christoph Pauly, Sebastian Slawik, Kristina Brix, Ralf Kautenburger, Frank Mücklich","doi":"10.3389/fmats.2024.1397937","DOIUrl":"https://doi.org/10.3389/fmats.2024.1397937","url":null,"abstract":"Introduction: Topographic surface patterning in the micro- and nanometer scale has evolved into a well applied approach in surface functionalization following biomimetic blueprints from nature. Depending on the production process an additional impact of process-related substrate modification has to be considered in functional surface optimization. This is especially true in case of antimicrobial applications of Cu surfaces where a modification of the substrate properties might impact bactericidal efficiency.Methods: In this regard, the effect of ultrashort pulsed direct laser interference patterning on the microstructure of pure Cu and resulting antimicrobial properties was investigated alongside line-like patterning in the scale of single bacterial cells.Results and Discussion: The process-induced microstructure modification was shown to play an important role in corrosion processes on Cu surfaces in saline environment, whereas the superficial microstructure impacts both corrosive interaction and ion emission. Surprisingly, antimicrobial efficiency is not predominantly following deviating trends in Cu ion release rates but rather depends on surface topography and wettability, which was shown to be impacted by the substrate microstructure state, as well. This highlights the need of an in-depth understanding on how different surface properties are simultaneously modulated during laser processing and how their interaction has to be designed to acquire an effective surface optimization e.g., to agitate active antimicrobial surface functionalization.","PeriodicalId":12524,"journal":{"name":"Frontiers in Materials","volume":"282 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141866990","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}
Developing eco-friendly polymeric plasticizers with excellent migration resistance is one of the research hotspots in the polyvinyl chloride (PVC) industry. A low-molecular-weight biobased polyester rubber (LMW-BPR) was synthesized from five biobased polyester monomers in a 100-L reactor and evaluated as a potential eco-friendly polymeric plasticizer for PVC. The obtained LMW-BPR is an amorphous polyester material with a low glass transition temperature of −48°C and a molecular weight of 22 kg/mol, which is lower than that of existing polyester rubber but higher than those of most polyester plasticizer commodities. Plasticized PVC composites with a total plasticizer content of 50 phr were prepared by using the mixture of LMW-BPR and di-isononyl cyclohexane-1,2-dicarboxylate (DINCH, an eco-friendly monomeric plasticizer commodity) as the plasticizer. The migration resistance test showed that the migration loss of plasticizer in plasticized PVC composite decreased significantly with the increase of LMW-BPR content. When the content of LMW-BPR reaches 30 phr, the plasticized PVC composites are almost nonmigratory. In addition, compared with PVC composite plasticized by pure DINCH, co-plasticized PVC composites containing LMW-BPR exhibit higher tensile strength and thermal stability, and their flexibility, low-temperature resistance and biocompatibility are also maintained at a similar level to the former. Overall, LMW-BPR is an effective eco-friendly polymeric plasticizer for PVC and also sustainable and scalable, thus it is worthy of wide application.
{"title":"Synthesis and performance evaluation of low-molecular-weight biobased polyester rubber as a novel eco-friendly polymeric plasticizer for polyvinyl chloride","authors":"Qinan Zhang, Jiahui Sun, Zehao Yao, Xuejia Ding, Zhao Wang, Liqun Zhang","doi":"10.3389/fmats.2024.1406469","DOIUrl":"https://doi.org/10.3389/fmats.2024.1406469","url":null,"abstract":"Developing eco-friendly polymeric plasticizers with excellent migration resistance is one of the research hotspots in the polyvinyl chloride (PVC) industry. A low-molecular-weight biobased polyester rubber (LMW-BPR) was synthesized from five biobased polyester monomers in a 100-L reactor and evaluated as a potential eco-friendly polymeric plasticizer for PVC. The obtained LMW-BPR is an amorphous polyester material with a low glass transition temperature of −48°C and a molecular weight of 22 kg/mol, which is lower than that of existing polyester rubber but higher than those of most polyester plasticizer commodities. Plasticized PVC composites with a total plasticizer content of 50 phr were prepared by using the mixture of LMW-BPR and di-isononyl cyclohexane-1,2-dicarboxylate (DINCH, an eco-friendly monomeric plasticizer commodity) as the plasticizer. The migration resistance test showed that the migration loss of plasticizer in plasticized PVC composite decreased significantly with the increase of LMW-BPR content. When the content of LMW-BPR reaches 30 phr, the plasticized PVC composites are almost nonmigratory. In addition, compared with PVC composite plasticized by pure DINCH, co-plasticized PVC composites containing LMW-BPR exhibit higher tensile strength and thermal stability, and their flexibility, low-temperature resistance and biocompatibility are also maintained at a similar level to the former. Overall, LMW-BPR is an effective eco-friendly polymeric plasticizer for PVC and also sustainable and scalable, thus it is worthy of wide application.","PeriodicalId":12524,"journal":{"name":"Frontiers in Materials","volume":"64 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141866994","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}
Pub Date : 2024-07-25DOI: 10.3389/fmats.2024.1443089
Muhammad Iftikhar Faraz
Vinyl ester/flax (VE/flax) bio-composites were made after incorporating hybrid concentrations (0, 3, and 6% by weight (wt)) of halloysite nanotubes (HNT), magnesium hydroxide (MHO) and chitosan infused ammonium polyphosphate (CAP) particles. The purpose of incorporation of these particles was to improve the fire-retardant (FR) properties of the VE/flax composite; however, its effect on mechanical properties was also evaluated. To reduce the number of experiments (from 27 to 9), Taguchi design of experiment was employed during composite fabrication phase. Initially, the burning time and burning rate of all the composites were calculated using a horizontal burning test while tensile properties were determined using a tensile test. To predict an optimum composition, a signal to noise (S/N) ratio analysis of the burning time and tensile strength was conducted as “larger is better” criteria. The combination of 6% MGO and 3% CAP was predicted to be an optimum hybrid filler for enhanced fire retardancy, while VE/flax composite with no filler proved to have the highest tensile strength. HNT was found to be the least effective filler for both tensile and fire-retardant properties. The predicted composition was then fabricated and validated through experimental characterizations. The fire-retardant properties of the optimized composite were additionally assessed using a limiting oxygen index (LOI) test and thermal stability was evaluated using a thermogravimetric analysis (TGA). The burning time of the optimized composite was found to be delayed by 46.5% of that of VE/flax composite, while its thermal degradation was 11.23% lower than VE/flax composite.
{"title":"Optimizing the synergistic effect of organic and inorganic fillers on fire-retardant and mechanical properties of vinyl ester/flax bio-composites","authors":"Muhammad Iftikhar Faraz","doi":"10.3389/fmats.2024.1443089","DOIUrl":"https://doi.org/10.3389/fmats.2024.1443089","url":null,"abstract":"Vinyl ester/flax (VE/flax) bio-composites were made after incorporating hybrid concentrations (0, 3, and 6% by weight (wt)) of halloysite nanotubes (HNT), magnesium hydroxide (MHO) and chitosan infused ammonium polyphosphate (CAP) particles. The purpose of incorporation of these particles was to improve the fire-retardant (FR) properties of the VE/flax composite; however, its effect on mechanical properties was also evaluated. To reduce the number of experiments (from 27 to 9), Taguchi design of experiment was employed during composite fabrication phase. Initially, the burning time and burning rate of all the composites were calculated using a horizontal burning test while tensile properties were determined using a tensile test. To predict an optimum composition, a signal to noise (S/N) ratio analysis of the burning time and tensile strength was conducted as “larger is better” criteria. The combination of 6% MGO and 3% CAP was predicted to be an optimum hybrid filler for enhanced fire retardancy, while VE/flax composite with no filler proved to have the highest tensile strength. HNT was found to be the least effective filler for both tensile and fire-retardant properties. The predicted composition was then fabricated and validated through experimental characterizations. The fire-retardant properties of the optimized composite were additionally assessed using a limiting oxygen index (LOI) test and thermal stability was evaluated using a thermogravimetric analysis (TGA). The burning time of the optimized composite was found to be delayed by 46.5% of that of VE/flax composite, while its thermal degradation was 11.23% lower than VE/flax composite.","PeriodicalId":12524,"journal":{"name":"Frontiers in Materials","volume":"6 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141777165","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}
Pub Date : 2024-07-25DOI: 10.3389/fmats.2024.1427541
Imran Haider, Iftikhar Hussain Gul, Shahid Aziz, Muhammad Iftikhar Faraz, Muhammad Ali Khan, Syed Husain Imran Jaffery, Dong-Won Jung
In high-speed microelectronic communication, efficient and reliable radome-enclosed antenna performance is highly desired, which depends on consistent dielectric, mechanical properties, and low moisture absorption. The purpose of this study is to investigate the dielectric properties of fiber-polymer matrix composite (PMC) radome over wideband frequency and the impact of environmental aging on its performance. The dielectric constant (Ɛr) of the SF/E0.8 (80% fiber loading) composite radome material decreased to 4% from its original value (3.93), and dielectric loss (δ) was reduced by 11% from 0.035 (2–18 GHz), while SEM morphology indicated fair interface bonding. Employing the Hallberg and Peck model, equivalent aging time (5–25 years), upon accelerated environmental aging, Ɛr was increased up to 3.69%, δ to 9.68%, and the moisture uptake in the SF/E0.8 composite was increased from 1.13% to 1.67%, while tensile strength was retained up to 90.62% of its original value (147.83 MPa), compression strength up to 93.56% of its original value (388.54 MPa), flexural strength up to 85.44% of its original value (286.77 MPa), and interlaminar shear strength up to 77.66% of its original value (22.03 MPa), respectively. SF/E0.8 radome-enclosed antenna gain was decreased to 1%, and the voltage standing wave ratio (VSWR) was increased to 1.04% from their original values. This gradual and small deviation of SF/Ex composite properties and radome electrical performance over the extended aging time is referred to as reliable and effective for radome applications.
{"title":"Environmental aging of reinforced polymer composite radome: reliability and performance investigation","authors":"Imran Haider, Iftikhar Hussain Gul, Shahid Aziz, Muhammad Iftikhar Faraz, Muhammad Ali Khan, Syed Husain Imran Jaffery, Dong-Won Jung","doi":"10.3389/fmats.2024.1427541","DOIUrl":"https://doi.org/10.3389/fmats.2024.1427541","url":null,"abstract":"In high-speed microelectronic communication, efficient and reliable radome-enclosed antenna performance is highly desired, which depends on consistent dielectric, mechanical properties, and low moisture absorption. The purpose of this study is to investigate the dielectric properties of fiber-polymer matrix composite (PMC) radome over wideband frequency and the impact of environmental aging on its performance. The dielectric constant (Ɛ<jats:sub>r</jats:sub>) of the SF/E<jats:sub>0.8</jats:sub> (80% fiber loading) composite radome material decreased to 4% from its original value (3.93), and dielectric loss (δ) was reduced by 11% from 0.035 (2–18 GHz), while SEM morphology indicated fair interface bonding. Employing the Hallberg and Peck model, equivalent aging time (5–25 years), upon accelerated environmental aging, Ɛ<jats:sub>r</jats:sub> was increased up to 3.69%, δ to 9.68%, and the moisture uptake in the SF/E<jats:sub>0.8</jats:sub> composite was increased from 1.13% to 1.67%, while tensile strength was retained up to 90.62% of its original value (147.83 MPa), compression strength up to 93.56% of its original value (388.54 MPa), flexural strength up to 85.44% of its original value (286.77 MPa), and interlaminar shear strength up to 77.66% of its original value (22.03 MPa), respectively. SF/E<jats:sub>0.8</jats:sub> radome-enclosed antenna gain was decreased to 1%, and the voltage standing wave ratio (VSWR) was increased to 1.04% from their original values. This gradual and small deviation of SF/E<jats:sub>x</jats:sub> composite properties and radome electrical performance over the extended aging time is referred to as reliable and effective for radome applications.","PeriodicalId":12524,"journal":{"name":"Frontiers in Materials","volume":"77 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141777166","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}
Pub Date : 2024-07-24DOI: 10.3389/fmats.2024.1447496
Ye-yang Chun, Zhengquan Liu, Yong He, He Wei, Dongpo Su
To elucidate the time-dependent swelling behavior of landfill sand-bentonite mixture liners under the effect of organic pollutants, an no loading swelling ratio test was conducted on mixtures with varying sand and diesel content. The evolution characteristics of the swelling time curve morphology were investigated. The micro-mechanisms underlying the swelling time effect evolution were explored. The results indicated that the sand-diesel interaction significantly altered the swelling time curve morphological characteristics of the mixture. As the sand content increased, the swelling coefficient at the stable state decreased. However, during the rapid swell phase, diesel-contaminated mixed soil does not exhibit the increase-then-decrease pattern in swell coefficient seen in unpolluted mixed soil. The duration of both the slow swelling phase and the time to reach a stable state were longer. Mechanistic analysis revealed that cation exchange capacity is insufficient to effectively analyze the evolution characteristics of the swelling time curve. Instead, the initial swelling potential of bentonite is the true indicator of the mixture’s swelling properties. The particle size distribution influences the changes in the swelling coefficient during the rapid swelling phase, but diesel alters the particle size distribution, mitigating its impact. The oil sealing effect within intra-aggregate and inter-aggregate pores not only weakened the swelling characteristics of the mixture at all stages but also increased the permeability resistance, thereby reducing the duration of the rapid swelling phase and extending the slow swelling and stable swelling phases.
{"title":"Temporal effect and evolution mechanism of sand-bentonite mixture liner swelling under the influence of sand and diesel","authors":"Ye-yang Chun, Zhengquan Liu, Yong He, He Wei, Dongpo Su","doi":"10.3389/fmats.2024.1447496","DOIUrl":"https://doi.org/10.3389/fmats.2024.1447496","url":null,"abstract":"To elucidate the time-dependent swelling behavior of landfill sand-bentonite mixture liners under the effect of organic pollutants, an no loading swelling ratio test was conducted on mixtures with varying sand and diesel content. The evolution characteristics of the swelling time curve morphology were investigated. The micro-mechanisms underlying the swelling time effect evolution were explored. The results indicated that the sand-diesel interaction significantly altered the swelling time curve morphological characteristics of the mixture. As the sand content increased, the swelling coefficient at the stable state decreased. However, during the rapid swell phase, diesel-contaminated mixed soil does not exhibit the increase-then-decrease pattern in swell coefficient seen in unpolluted mixed soil. The duration of both the slow swelling phase and the time to reach a stable state were longer. Mechanistic analysis revealed that cation exchange capacity is insufficient to effectively analyze the evolution characteristics of the swelling time curve. Instead, the initial swelling potential of bentonite is the true indicator of the mixture’s swelling properties. The particle size distribution influences the changes in the swelling coefficient during the rapid swelling phase, but diesel alters the particle size distribution, mitigating its impact. The oil sealing effect within intra-aggregate and inter-aggregate pores not only weakened the swelling characteristics of the mixture at all stages but also increased the permeability resistance, thereby reducing the duration of the rapid swelling phase and extending the slow swelling and stable swelling phases.","PeriodicalId":12524,"journal":{"name":"Frontiers in Materials","volume":"44 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141777167","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}
Pub Date : 2024-07-19DOI: 10.3389/fmats.2024.1415144
Weidong Yang, Huaxin Liu, Hesong Wang
In enhancing the high-temperature resistance of concrete, incorporating fiber materials was established as an effective approach. This study focused on evaluating the cubic compressive strength, splitting tensile strength, prism compressive strength, and flexural strength of plain concrete, nano-SiO2 concrete, and basalt fiber nano-SiO2 concrete when subjected to elevated temperatures. Subsequently, a concrete strength prediction model was established, and a microstructure analysis of the specimens was conducted. The results indicated that after exposure to 800°C, the cubic compressive strength, splitting tensile strength, prism compressive strength, and flexural strength of basalt fiber-reinforced nano-SiO₂ concrete increased by 33.7%, 15.6%, 10.4%, and 17.2%, respectively, compared to plain concrete. Furthermore, the fitting values of the strength prediction model were all above 0.9. Microstructure analysis revealed that the filling effect of nano-SiO₂ made the concrete matrix denser, while the basalt fiber effectively restrained the formation of cracks in the concrete matrix. Additionally, nano-SiO₂ promoted the formation of hydrated calcium silicate from Ca(OH)₂(CH) and adhered to the basalt fiber, enhancing bonding and reducing the risk of concrete spalling.
{"title":"Experimental study on mechanical properties of basalt fiber reinforced nano-SiO2 concrete after high temperature","authors":"Weidong Yang, Huaxin Liu, Hesong Wang","doi":"10.3389/fmats.2024.1415144","DOIUrl":"https://doi.org/10.3389/fmats.2024.1415144","url":null,"abstract":"In enhancing the high-temperature resistance of concrete, incorporating fiber materials was established as an effective approach. This study focused on evaluating the cubic compressive strength, splitting tensile strength, prism compressive strength, and flexural strength of plain concrete, nano-SiO<jats:sub>2</jats:sub> concrete, and basalt fiber nano-SiO<jats:sub>2</jats:sub> concrete when subjected to elevated temperatures. Subsequently, a concrete strength prediction model was established, and a microstructure analysis of the specimens was conducted. The results indicated that after exposure to 800°C, the cubic compressive strength, splitting tensile strength, prism compressive strength, and flexural strength of basalt fiber-reinforced nano-SiO₂ concrete increased by 33.7%, 15.6%, 10.4%, and 17.2%, respectively, compared to plain concrete. Furthermore, the fitting values of the strength prediction model were all above 0.9. Microstructure analysis revealed that the filling effect of nano-SiO₂ made the concrete matrix denser, while the basalt fiber effectively restrained the formation of cracks in the concrete matrix. Additionally, nano-SiO₂ promoted the formation of hydrated calcium silicate from Ca(OH)₂(CH) and adhered to the basalt fiber, enhancing bonding and reducing the risk of concrete spalling.","PeriodicalId":12524,"journal":{"name":"Frontiers in Materials","volume":"64 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141745416","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}
Pub Date : 2024-07-09DOI: 10.3389/fmats.2024.1435814
Honggang Zhang, Yangpeng Zhang, Jie Chen, Wenchang Liu, Wensheng Wang
Waste rubber modified bitumen has gained significant attention as a sustainable and innovative material in the field of pavement engineering. This study aims to evaluate the performance of rubber modified bitumen mastic by considering its rheological properties, specifically focusing on preparation parameters, i.e., rubber content, mesh number, and filler to bitumen ratio. From the experimental results, the rheological properties of rubber modified bitumen mastic were significantly influenced by preparation parameters. Increasing the rubber powder content in bitumen mastic results in higher viscosity. Increasing the rubber content improves high-temperature rutting resistance to a certain extent, however, excessive rubber powder content would result in weakened high-temperature performance improvement. The rutting factor decreases gradually with an increase in the rubber mesh number. A ratio of filler to bitumen of 0.95 exhibits the best resistance to rutting at high temperatures. Higher rubber content and larger mesh number correspond to stronger low-temperature crack resistance in bitumen mastic. As the ratio of filler to bitumen increases, the low-temperature deformation capacity gradually decreases, resulting in weaker low-temperature crack resistance. Based on the grey relation analysis, the ratio of filler to bitumen has the greatest impact on the high and low-temperature rheological properties of bitumen mastic, followed by the rubber content. The rubber mesh number has a relatively lower impact. It is crucial to control the ratio of filler to bitumen to avoid excessive values. When possible, a higher rubber powder content should be used while meeting process requirements. These findings provide valuable insights into the design and optimization of rubber modified bitumen mastic, which can contribute to the development of sustainable and high-performance bitumen mixtures, promoting the use of recycled rubber in pavement engineering.
{"title":"Influence of preparation parameters on rheological properties and relation analysis of waste rubber modified bitumen mastic","authors":"Honggang Zhang, Yangpeng Zhang, Jie Chen, Wenchang Liu, Wensheng Wang","doi":"10.3389/fmats.2024.1435814","DOIUrl":"https://doi.org/10.3389/fmats.2024.1435814","url":null,"abstract":"Waste rubber modified bitumen has gained significant attention as a sustainable and innovative material in the field of pavement engineering. This study aims to evaluate the performance of rubber modified bitumen mastic by considering its rheological properties, specifically focusing on preparation parameters, i.e., rubber content, mesh number, and filler to bitumen ratio. From the experimental results, the rheological properties of rubber modified bitumen mastic were significantly influenced by preparation parameters. Increasing the rubber powder content in bitumen mastic results in higher viscosity. Increasing the rubber content improves high-temperature rutting resistance to a certain extent, however, excessive rubber powder content would result in weakened high-temperature performance improvement. The rutting factor decreases gradually with an increase in the rubber mesh number. A ratio of filler to bitumen of 0.95 exhibits the best resistance to rutting at high temperatures. Higher rubber content and larger mesh number correspond to stronger low-temperature crack resistance in bitumen mastic. As the ratio of filler to bitumen increases, the low-temperature deformation capacity gradually decreases, resulting in weaker low-temperature crack resistance. Based on the grey relation analysis, the ratio of filler to bitumen has the greatest impact on the high and low-temperature rheological properties of bitumen mastic, followed by the rubber content. The rubber mesh number has a relatively lower impact. It is crucial to control the ratio of filler to bitumen to avoid excessive values. When possible, a higher rubber powder content should be used while meeting process requirements. These findings provide valuable insights into the design and optimization of rubber modified bitumen mastic, which can contribute to the development of sustainable and high-performance bitumen mixtures, promoting the use of recycled rubber in pavement engineering.","PeriodicalId":12524,"journal":{"name":"Frontiers in Materials","volume":"57 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141576316","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}
Pub Date : 2024-07-08DOI: 10.3389/fmats.2024.1422398
Mariya Aleksandrova
Introduction: Traps at the interface between carbyne and palladium nanocoatings, produced at different growth conditions, are explored by current-voltage characteristics, scanning electron microscopy and thermal stimulation of charges for evaluation of their nature. It was found that the Pd films can form an Ohmic contact with the carbyne at certain deposition conditions and such deviated from the Ohmic behavior according to the RF sputtering voltage. This growth parameter was found to affect the interfacial traps formation on the carbyne surface, which is important feature for the charge trapping and releasing properties for hydrogen isotopes in the context of the energy release applications.Methods, Results and Discussion: The sputtering voltages of 0.5 kV and 0.7 kV were found unsuitable for controlled trap formation. Based on the currentvoltage and thermally stimulated current (TSC) measurements, a sputtering voltage of 0.9 kV appeared to be more favorable compared to 0.5 kV and 0.7 kV. At 0.9 kV thermal activation of charge carriers are enabled at lower thermal energies, showing a distinct change in TSC behavior correlated to trap activation.
{"title":"Investigating the role of palladium electrical contacts in interactions with carbyne nanomaterial solid matter","authors":"Mariya Aleksandrova","doi":"10.3389/fmats.2024.1422398","DOIUrl":"https://doi.org/10.3389/fmats.2024.1422398","url":null,"abstract":"Introduction: Traps at the interface between carbyne and palladium nanocoatings, produced at different growth conditions, are explored by current-voltage characteristics, scanning electron microscopy and thermal stimulation of charges for evaluation of their nature. It was found that the Pd films can form an Ohmic contact with the carbyne at certain deposition conditions and such deviated from the Ohmic behavior according to the RF sputtering voltage. This growth parameter was found to affect the interfacial traps formation on the carbyne surface, which is important feature for the charge trapping and releasing properties for hydrogen isotopes in the context of the energy release applications.Methods, Results and Discussion: The sputtering voltages of 0.5 kV and 0.7 kV were found unsuitable for controlled trap formation. Based on the currentvoltage and thermally stimulated current (TSC) measurements, a sputtering voltage of 0.9 kV appeared to be more favorable compared to 0.5 kV and 0.7 kV. At 0.9 kV thermal activation of charge carriers are enabled at lower thermal energies, showing a distinct change in TSC behavior correlated to trap activation.","PeriodicalId":12524,"journal":{"name":"Frontiers in Materials","volume":"64 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141578117","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}