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Effect of dietary fibre on the gastrointestinal microbiota during critical illness:A scoping review
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作者 Angajendra N Ghosh Calum J Walsh +2 位作者 Matthew J Maiden Tim P Stinear Adam M Deane 《World Journal of Critical Care Medicine》 2025年第1期49-59,共11页
The systemic effects of gastrointestinal(GI)microbiota in health and during chronic diseases is increasingly recognised.Dietary strategies to modulate the GI microbiota during chronic diseases have demonstrated promis... The systemic effects of gastrointestinal(GI)microbiota in health and during chronic diseases is increasingly recognised.Dietary strategies to modulate the GI microbiota during chronic diseases have demonstrated promise.While changes in dietary intake can rapidly change the GI microbiota,the impact of dietary changes during acute critical illness on the microbiota remain uncertain.Dietary fibre is metabolised by carbohydrate-active enzymes and,in health,can alter GI microbiota.The aim of this scoping review was to describe the effects of dietary fibre supplementation in health and disease states,specifically during critical illness.Randomised controlled trials and prospective cohort studies that include adults(>18 years age)and reported changes to GI microbiota as one of the study outcomes using non-culture methods,were identified.Studies show dietary fibres have an impact on faecal microbiota in health and disease.The fibre,inulin,has a marked and specific effect on increasing the abundance of faecal Bifidobacteria.Short chain fatty acids produced by Bifidobacteria have been shown to be beneficial in other patient populations.Very few trials have evaluated the effect of dietary fibre on the GI microbiota during critical illness.More research is necessary to establish optimal fibre type,doses,duration of intervention in critical illness. 展开更多
关键词 Gastrointestinal microbiota Dietary fibre HEALTH Critical illness Short chain fatty acids
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Advances in fibre-optic-based slope reinforcement monitoring:A review
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作者 Ashis Acharya Tetsuya Kogure 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第2期1263-1284,共22页
Real-time assessment of slope reinforcements to diagnose their state in all stages of service life is imperative for prompt evaluation of slope stability and establishing an efficient early warning(EW)system.Many poin... Real-time assessment of slope reinforcements to diagnose their state in all stages of service life is imperative for prompt evaluation of slope stability and establishing an efficient early warning(EW)system.Many point-based monitoring instruments have been used in the last few decades.However,these sensors suffer from a particular risk of detection failures and practical limitations.Fibre-optic sensing(FOS)technologies have been developed,tested,and validated across various geoengineering applications,including slope monitoring,as they offer exceptional advantages,such as high data-carrying capacity,precise mapping of physical parameters,durability,and immunity to electromagnetic interference.The deformation of rock/soil causes the deformation and fracture of reinforcement materials,which are subsequently transferred to the encapsulated fibre-optic(FO)sensors,providing valuable information on reinforcements'safety state and performance for early failure detection.This paper is devoted to critically analysing the application of cutting-edge FOS technologies for slope reinforcement monitoring.Firstly,a concise overview of the fundamental principles underlying discrete and distributed FOS methods is provided.The key considerations for selecting FO cables and the appropriate packaging techniques necessary to withstand the challenges posed by complex geological environments are also summarised.We delve into the details of three distinct cable installation techniques within slope reinforcement components:surface bonding,slot embedment,and clamping.The recent advancements in FOS methods for monitoring slope reinforcements such as rock bolts,soil nails,anti-slide piles,geosynthetics,and retaining walls are extensively reviewed.The paper addresses this novel sensing technique's challenges and comprehensively explores its prospects.This review is anticipated to be a valuable resource for geoengineers and researchers involved in slope monitoring through FOS technology,offering insightful perspectives and guidance. 展开更多
关键词 Optical fibre Slope reinforcement Slope monitoring fibre bragg grating(FBG) Distributed fibre-optic sensing(FOS) Early warning(EW)
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High Lignin Content Polymer Filaments as Carbon Fibre Precursors
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作者 Rui Ribeiro Miguel Guerreiro +5 位作者 Renato Reis Joana T.Martins Jorge M.Vieira Mariana Martins da Silva JoséA.Covas Maria C.Paiva 《Journal of Renewable Materials》 2025年第10期1859-1880,共22页
The growing environmental awareness,the search for alternatives to fossil resources,and the goal of achieving a circular economy have all contributed to the increasing valorization of biowaste to produce bio-based pol... The growing environmental awareness,the search for alternatives to fossil resources,and the goal of achieving a circular economy have all contributed to the increasing valorization of biowaste to produce bio-based polymers and other high-value products.Among the various biowaste materials,lignin has gained significant attention due to its high aromatic carbon content,low cost,and abundance.Lignin is predominantly sourced as a byproduct from the paper industry,available in large quantities from hardwood and softwood,with variations in chemical structure and susceptibility to hydrolysis.This study focuses on softwood lignin obtained through the LignoForce^(TM) technology,comparing the thermal and chemical characteristics,and stability,of a recently produced batch with that of a batch that has been stored for four years.Additionally,the development of lignin-based thermoplastic polymer mixtures using Polyethylene Terephthalate Glycol(PET-G)and a blend of Polycarbonate and Acrylonitrile-Butadiene-Styrene(PC/ABS)with high lignin content(50–60 wt%)is explored,as well as the production of filaments for carbon fiber production.For this purpose,following melt mixing,the lignin-based mixtures were spun into filaments,which were subsequently subjected to thermal stabilization in an oxidative atmosphere.The lignin phase was well distributed in the PET-Gmatrix and the twomaterials presented a good interface,which further improved after thermal treatment under an oxidative atmosphere.After thermal treatment an increase in tensile modulus,tensile strength,and elongation at break of approximately 160%,200%,and 100%,respectively,was observed,confirming the good interface established,and consistent with structural changes such as cross-linking.Conversely,the PC/ABS blend did not form a good interface with the lignin domains after melt mixing.Although the interactions improved after thermal treatment,the tensile strength and elongation at break decreased by approximately 30%,while themodulus increased by approximately 20%.Overall,the good processability of the lignin/polymer mixtures into filaments,and their physical,chemical,and mechanical characterization before and after thermal oxidation are good indicators of the potential as precursors for carbon fiber production. 展开更多
关键词 LIGNIN lignin-based fibers PET-G PC/ABS thermal stabilization carbon fibre precursor
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A Comprehensive Review of Natural Rubber Composites:Properties,Compounding Aspects,and Renewable Practices with Natural Fibre Reinforcement
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作者 Mohamad Firdaus Omar Fathilah Ali +6 位作者 Mohammed Saedi Jami Azlin Suhaida Azmi Farah Ahmad Mohd Zahid Marzuki Shantha Kumari Muniyandi Zuraidah Zainudin Minsoo P.Kim 《Journal of Renewable Materials》 2025年第3期497-538,共42页
This review provides a comprehensive overview of natural rubber(NR)composites,focusing on their properties,compounding aspects,and renewable practices involving natural fibre reinforcement.The properties of NR are inf... This review provides a comprehensive overview of natural rubber(NR)composites,focusing on their properties,compounding aspects,and renewable practices involving natural fibre reinforcement.The properties of NR are influenced by the compounding process,which incorporates ingredients such as elastomers,vulcanizing agents,accelerators,activators,and fillers like carbon black and silica.While effective in enhancing properties,these fillers lack biodegradability,prompting the exploration of sustainable alternatives.The potential of natural fibres as renewable reinforcements in NR composites is thoroughly covered in this review,highlighting both their advan-tages,such as improved sustainability,and the challenges they present,such as compatibility with the rubber matrix.Surface treatment methods,including alkali and silane treatments,are also discussed as solutions to improve fibre-matrix adhesion and mitigate these challenges.Additionally,the review highlights the potential of oil palm empty fruit bunch(EFB)fibres as a natural fibre reinforcement.The abundance of EFB fibres and their alignment with sustainable practices make them promising substitutes for conventional fillers,contributing to valuable knowledge and supporting the broader move towards renewable reinforcement to improve sustain-ability without compromising the key properties of rubber composites. 展开更多
关键词 Natural rubber composites natural fibres RENEWABLE REINFORCEMENT VULCANIZATION FILLERS carbon black silica surface treatment sound absorption acoustics
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Overview of Jute Fibre as Thermoplastic Matrix Polymer Reinforcement
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作者 Tezara Cionita Mohammad Hazim Mohamad Hamdan +9 位作者 Januar Parlaungan Siregar Deni Fajar Fitriyana Ramli Junid Wong Ling Shing Jamiluddin Jaafar Agustinus Purna Irawan Teuku Rihayat Rifky Ismail Athanasius Priharyoto Bayuseno Emilianus Jehadus 《Journal of Renewable Materials》 EI CAS 2024年第3期457-483,共27页
Recent decades have seen a substantial increase in interest in research on natural fibres that is aligned with sustainable development goals(SDGs).Due to their renewable resources and biodegradability,natural fiberrei... Recent decades have seen a substantial increase in interest in research on natural fibres that is aligned with sustainable development goals(SDGs).Due to their renewable resources and biodegradability,natural fiberreinforced composites have been investigated as a sustainable alternative to synthetic materials to reduce the usage of hazardous waste and environmental pollution.Among the natural fibre,jute fibre obtained from a bast plant has an increasing trend in the application,especially as a reinforcement material.Numerous research works have been performed on jute fibre with regard to reinforced thermoset and thermoplastic composites.Nevertheless,current demands on sustainable materials have required new developments in thermoplastic composites.In this paper,the author reviews jute plants as reinforcement materials for thermoplastic matrix polymers.This review provides an overview of the sustainability of jute plants as reinforcement material for thermoplastic matrix polymers.The overview on jute based thermoplastic composites focused on the thermal behavior and mechanical properties.Apart from physical,chemical,and mechanical properties,the study also covers the current and perspectives for future research challenges faced by the researchers on jute fibre reinforced thermoplastic composites. 展开更多
关键词 Jute fibre sustainable development goals(SDGs) natural fibre THERMOPLASTIC composite sustainable manufacturing
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Fibrotic liver extracellular matrix induces cancerous phenotype in biomimetic micro-tissues of hepatocellular carcinoma model
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作者 Kosar Nouri Abbas Piryaei +5 位作者 Homeyra Seydi Ibrahim Zarkesh Ibrahim Ghoytasi Bahare Shokouhian Mustapha Najimi Massoud Vosough 《Hepatobiliary & Pancreatic Diseases International》 2025年第1期92-103,共12页
Background: Despite considerable advancements in identifying factors contributing to the development of hepatocellular carcinoma(HCC), the pathogenesis of HCC remains unclear. In many cases, HCC is a consequence of pr... Background: Despite considerable advancements in identifying factors contributing to the development of hepatocellular carcinoma(HCC), the pathogenesis of HCC remains unclear. In many cases, HCC is a consequence of prolonged liver fibrosis, resulting in the formation of an intricate premalignant microenvironment. The accumulation of extracellular matrix(ECM) is a hallmark of premalignant microenvironment. Given the critical role of different matrix components in regulating cell phenotype and function, this study aimed to elucidate the interplay between the fibrotic matrix and malignant features in HCC. Methods: Liver tissues from both control(normal) and carbon tetrachloride(CCl_(4))-induced fibrotic rats were decellularized using sodium dodecyl sulfate(SDS) and Triton X-100. The resulting hydrogel from decellularized ECM was processed into micro-particles via the water-in-oil emulsion method. Microparticles were subsequently incorporated into three-dimensional liver biomimetic micro-tissues(MTs) comprising Huh-7 cells, human umbilical vein endothelial cells(HUVECs), and LX-2 cells. The MTs were evaluated using the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium(MTS) assay at day 11, immunofluorescence staining, immunoblotting, and spheroid migration assay at day 14 after co-culture. Results: Fibrotic matrix from CCl4-treated rat livers significantly enhanced the growth rate of the MTs and their expression of CCND1 as compared to the normal one. Fibrotic matrix, also induced the expression of epithelial-to-mesenchymal transition(EMT)-associated genes such as TWIST1, ACTA2, MMP9, CDH2, and VIMENTIN in the MTs as compared to the normal matrix. Conversely, the expression of CDH1 and hepatic maturation genes HNF4A, ALB, CYP3A4 was decreased in the MTs when the fibrotic matrix was used. Furthermore, the fibrotic matrix increased the migration of the MTs and their secretion of alpha-fetoprotein. Conclusions: Our findings suggest a regulatory role for the fibrotic matrix in promoting cancerous phenotype, which could potentially accelerate the progression of malignancy in the liver. 展开更多
关键词 Liver fibrosis Decellularized extracellular matrix SPHEROID Epithelial-to-mesenchymal transition Cell differentiation Hepatocellular carcinoma
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Manufacturing and thermal properties of steel-carbon fibre/polyetheretherketone(CF/PEEK)hybrid shafts using laser-assisted in-situ consolidation
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作者 Zequan DING Congcong LUAN +7 位作者 Xinhua YAO Lingyu CHENG Yuyang JI Chengcheng NIU Ningguo DONG Kai ZHAO Zhibin RUAN Jianzhong FU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第10期917-930,共14页
A novel steel–carbon fibre/polyetheretherketone(CF/PEEK)hybrid shaft is proposed,considering the thermal stability,negative coefficient of thermal expansion in fibre orientation,and high stiffness of CF/PEEK,which is... A novel steel–carbon fibre/polyetheretherketone(CF/PEEK)hybrid shaft is proposed,considering the thermal stability,negative coefficient of thermal expansion in fibre orientation,and high stiffness of CF/PEEK,which is expected to suppress the thermal deformation of shafts.A laser-assisted in-situ consolidation(LAC)process,together with its equipment,was developed to manufacture the hybrid shaft.Firstly,the optimal process parameters,including the laser-heated temperature and placement speed,were investigated.A maximum short-beam shear strength of 80.7 MPa was achieved when the laser-heated temperature was 500°C and the placement speed was 100 mm/s.In addition,the failure modes and the effect of environmental temperature on the CF/PEEK samples were analyzed.Both interlayer cracks and inelastic deformation failure modes were observed.The formation and propagation of cracks were further investigated through digital image correlation(DIC).Furthermore,internal defects of the CF/PEEK sample were detected using X-ray tomography scans,and a minimum porosity of 0.23%was achieved with the optimal process parameters.Finally,two steel–CF/PEEK hybrid shafts,with different fibre orientations,were manufactured based on the optimal process parameters.The surface temperature distributions and thermal deformations were investigated using a self-established deformation/temperature measurement platform.The hybrid shaft showed an 85.7%reduction in radial displacement with hoop fibre orientation and an 11.5%reduction in axial displacement with cross fibre orientation compared with the steel shaft.The results indicate that the proposed method has great potential to improve the thermal stability of hybrid shafts and the accuracy of machine tools. 展开更多
关键词 Thermal characteristics Steel-carbon fibre/polyetheretherketone(CF/PEEK)hybrid shaft Laser-assisted in-situ consolidation(LAC) Thermal deformation
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Abnormal collagen deposition mediated by cartilage oligomeric matrix protein in the pathogenesis of oral submucous fibrosis
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作者 Yafei Xiong Xuechun Li +3 位作者 Bincan Sun Jie Zhang Xiaoshan Wu Feng Guo 《International Journal of Oral Science》 2025年第3期422-433,共12页
Abnormal accumulation of collagen fibrils is a hallmark feature of oral submucous fibrosis(OSF).However,the precise characteristics and underlying mechanisms remain unclear,impeding the advancement of potential therap... Abnormal accumulation of collagen fibrils is a hallmark feature of oral submucous fibrosis(OSF).However,the precise characteristics and underlying mechanisms remain unclear,impeding the advancement of potential therapeutic approaches.Here,we observed that collagen Ⅰ,the main component of the extracellular matrix,first accumulated in the lamina propria and subsequently in the submucosa of OSF specimens as the disease progressed.Using RNA-seq and Immunofluorescence in OSF specimens,we screened the cartilage oligomeric matrix protein(COMP)responsible for the abnormal collagen accumulation.Genetic COMP deficiency reduced arecoline-stimulated collagen I deposition significantly in vivo.In comparison,both COMP and collagen Ⅰ were upregulated under arecoline stimulation in wild-type mice.Human oral buccal mucosal fibroblasts(hBMFs)also exhibited increased secretion of COMP and collagen I after stimulation in vitro.COMP knockdown in hBMFs downregulates arecoline-stimulated collagen Ⅰ secretion.We further demonstrated that hBMFs present heterogeneous responses to arecoline stimulation,of which COMP-positive fibroblasts secrete more collagen Ⅰ.Since COMP is a molecular bridge with Fibril-associated collagens with Interrupted Triple helices(FACIT)in the collagen network,we further screened and identified collagen XIV,a FACIT member,co-localizing with both COMP and collagen Ⅰ.Collagen XIV expression increased under arecoline stimulation in wild-type mice,whereas it was hardly expressed in the Comp^(-/-) mice,even with under stimulation.In summary,we found that COMP may mediates abnormal collagen Ⅰ deposition by functions with collagen XIV during the progression of OSF,suggesting its potential to be targeted in treating OSF. 展开更多
关键词 extracellular matrixfirst cartilage oli oral submucous fibrosis collagen XIV lamina propria collagen fibrils cartilage oligomeric matrix protein collagenⅠ
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基于Matrix Core的高性能多维FFT设计与优化 被引量:1
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作者 陆璐 祝松祥 +2 位作者 田卿燕 林海山 郭逸劼 《华南理工大学学报(自然科学版)》 北大核心 2025年第3期20-30,共11页
快速傅里叶变换(FFT)算法广泛应用于科学计算等领域。为了充分挖掘图形处理器(GPU)的计算能力并进一步提高FFT的计算效率,该文针对矩阵形式的Stockham FFT,提出了一种基于Matrix Core的高性能多维FFT计算方案。在计算优化方面,该方案利... 快速傅里叶变换(FFT)算法广泛应用于科学计算等领域。为了充分挖掘图形处理器(GPU)的计算能力并进一步提高FFT的计算效率,该文针对矩阵形式的Stockham FFT,提出了一种基于Matrix Core的高性能多维FFT计算方案。在计算优化方面,该方案利用Matrix Core加速FFT计算中的矩阵乘运算,同时通过编译器内部指令完成小粒度的矩阵乘加,使得Matrix Core支持更多尺寸的FFT计算。在内存优化方面,该方案使用2层迭代策略,以充分利用共享内存,减少与全局内存的数据交换;根据Matrix Core的矩阵数据在各个线程寄存器中的分布规律,直接在寄存器上完成FFT计算中大量存在的矩阵逐元素乘操作;通过对共享内存中的数据进行重排来缓解存储体冲突,并采用双缓冲策略缓解访存瓶颈。该文还提出了高效的矩阵转置策略,以加速多维FFT计算。在AMD MI250 GPU平台上将该方案与GPU上主流的高性能FFT计算库rocFFT和VkFFT进行了比较实验,结果表明:该方案在AMD MI250上的1维、2维和3维FFT平均计算效率均优于rocFFT和VkFFT,3维FFT的平均计算效率为rocFFT的1.5倍,为VkFFT的2.0倍,具有较好的性能提升;mcFFT的计算精度与rocFFT和VkFFT保持在相同水平。 展开更多
关键词 图形处理器 matrix Core 快速傅里叶变换 矩阵乘法
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基于Matrix Core的小尺寸批量矩阵乘法设计与优化
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作者 陆璐 赵容 +1 位作者 梁志宏 索思亮 《华南理工大学学报(自然科学版)》 北大核心 2025年第9期48-58,共11页
通用矩阵乘法(GEMM)是线性代数中最重要的运算,来自不同科学领域的许多应用程序都将其关键部分转换为使用GEMM的形式。GEMM广泛应用于大模型、机器学习、科学计算和信号处理等领域。特别是半精度的批处理GEMM(即FP16)一直是许多深度学... 通用矩阵乘法(GEMM)是线性代数中最重要的运算,来自不同科学领域的许多应用程序都将其关键部分转换为使用GEMM的形式。GEMM广泛应用于大模型、机器学习、科学计算和信号处理等领域。特别是半精度的批处理GEMM(即FP16)一直是许多深度学习框架的核心操作。目前AMD GPU上半精度批处理GEMM的访存和计算利用率不足,急需优化。为此,该文提出了一种半精度批处理GEMM(HGEMM)的图形处理器(GPU)优化方案。分块策略方面,根据输入矩阵块大小为线程分配相同的访存量和计算量,同时线程计算多个矩阵乘法,以提高计算单元的利用率。访存优化方面,以多读数据为代价,为每个线程分配相同访存量以便于编译器优化,保证访存和计算时间相互掩盖。对于矩阵尺寸小于16的极小尺寸批处理HGEMM,该文利用4×4×4的Matrix Core及其对应的分块方案,在提升访存性能的同时减少Matrix Core计算资源的浪费,并提供是否使用共享内存的选项来达到最高性能。在AMD GPU MI210平台上,将该方案与rocBLAS的2个算子进行性能对比,结果表明:该方案在AMD GPU MI210上的平均性能为rocBLASHGEMMBatched的4.14倍,rocBLASGEMMExBatched的4.96倍;对于极小尺寸批处理HGEMM,平均性能为rocBLASHGEMMBatched的18.60倍,rocBLASGEMMExBatched的14.02倍。 展开更多
关键词 图形处理器 matrix Core 矩阵乘法 访存优化
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Interfacial microstructure and chemical stability during diffusion bonding of single crystal Al_2O_3-fibres with Ni25.8Al9.6Ta8.3Cr matrix
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作者 万小军 林建国 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第5期1023-1028,共6页
BN coated A1203 fibre-reinforced NiAl-alloy composites were fabricated by hot pressing at 1 200-1 400 ℃, and the interracial microstructure and chemical stability of BN coated Al2O3 fibre-reinforced NiAl-alloy compos... BN coated A1203 fibre-reinforced NiAl-alloy composites were fabricated by hot pressing at 1 200-1 400 ℃, and the interracial microstructure and chemical stability of BN coated Al2O3 fibre-reinforced NiAl-alloy composites were investigated by scanning electron microscopy (SEM) and analytical transmission electron microscopy (TEM). It was found that the complicated chemical reactions and diffusion processes happened in the interface area between BN-layer and Ni25.8A19.6Ta8.3 during the hot pressing at 1 200-1 400 ℃. A continuous AlN-layer was formed at the interface due to the reaction between NiAl and BN. At the same time, Cr diffused extensively into the BN-layer and reacted with boron to form Cr boride precipitates (CrsB3). In addition, a few particles of Ta-rich phase were also precipitated in NiAl matrix near the interface. 展开更多
关键词 NiAl alloy composite Al2O3 fibre diffusion bonding
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In Situ Polymer Gel Electrolyte in Boosting Scalable Fibre Lithium Battery Applications 被引量:1
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作者 Jie Luo Qichong Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第11期170-173,共4页
The poor interfacial stability not only deteriorates fibre lithium-ion batteries(FLBs)performance but also impacts their scalable applications.To efficiently address these challenges,Prof.Huisheng Peng team proposed a... The poor interfacial stability not only deteriorates fibre lithium-ion batteries(FLBs)performance but also impacts their scalable applications.To efficiently address these challenges,Prof.Huisheng Peng team proposed a generalized channel structures strategy with optimized in situ polymerization technology in their recent study.The resultant FLBs can be woven into different-sized powering textiles,providing a high energy density output of 128 Wh kg^(-1) and simultaneously demonstrating good durability even under harsh conditions.Such a promising strategy expands the horizon in developing FLB with particular polymer gel electrolytes,and significantly ever-deepening understanding of the scaled wearable energy textile system toward a sustainable future. 展开更多
关键词 High-performance fibre lithium batteries Gel electrolytes Channel structures Stable interface Scalable application
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Manufacturing Titanium Metal Matrix Composites by Consolidating Matrix Coated Fibres 被引量:3
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作者 Hua-Xin PENGDepartment of Aerospace Engineering, University of Bristol, University Walk, Bristol, BS8 1TR, UK 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第5期647-651,共5页
Titanium metal matrix composites (TiMMCs) reinforced by continuous silicon carbide fibres are being developed for aerospace applications. TiMMCs manufactured by the consolidation of matrix-coated fibre (MCF) metho... Titanium metal matrix composites (TiMMCs) reinforced by continuous silicon carbide fibres are being developed for aerospace applications. TiMMCs manufactured by the consolidation of matrix-coated fibre (MCF) method offer optimum properties because of the resulting uniform fibre distribution, minimum fibre damage and fibre volume fraction control. In this paper, the consolidation of Ti-6Al-4V matrix-coated SiC fibres during vacuum hot pressing has been investigated. Experiments were carried out on multi-ply MCFs under vacuum hot pressing (VHP). In contrast to most of existing studies, the fibre, arrangement has been carefully controlled either in square or hexagonal arrays throughout the consolidated sample. This has enabled the dynamic consolidation behaviour of MCFs to be demonstrated by eliminating the fibre re-arrangement during the VHP process. The microstructural evolution of the matrix coating was reported and the deformation mechanisms involved were discussed. 展开更多
关键词 Titanium matrix composites matrix-coated fibres Vacuum hot pressing MICROSTRUCTURE Dynamic denslfication
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Optical Fibre Communication Feature Analysis and Small Sample Fault Diagnosis Based on VMD-FE and Fuzzy Clustering 被引量:1
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作者 Xiangqun Li Jiawen Liang +4 位作者 Jinyu Zhu Shengping Shi Fangyu Ding Jianpeng Sun Bo Liu 《Energy Engineering》 EI 2024年第1期203-219,共17页
To solve the problems of a few optical fibre line fault samples and the inefficiency of manual communication optical fibre fault diagnosis,this paper proposes a communication optical fibre fault diagnosis model based ... To solve the problems of a few optical fibre line fault samples and the inefficiency of manual communication optical fibre fault diagnosis,this paper proposes a communication optical fibre fault diagnosis model based on variational modal decomposition(VMD),fuzzy entropy(FE)and fuzzy clustering(FC).Firstly,based on the OTDR curve data collected in the field,VMD is used to extract the different modal components(IMF)of the original signal and calculate the fuzzy entropy(FE)values of different components to characterize the subtle differences between them.The fuzzy entropy of each curve is used as the feature vector,which in turn constructs the communication optical fibre feature vector matrix,and the fuzzy clustering algorithm is used to achieve fault diagnosis of faulty optical fibre.The VMD-FE combination can extract subtle differences in features,and the fuzzy clustering algorithm does not require sample training.The experimental results show that the model in this paper has high accuracy and is relevant to the maintenance of communication optical fibre when compared with existing feature extraction models and traditional machine learning models. 展开更多
关键词 Optical fibre fault diagnosis OTDR curve variational mode decomposition fuzzy entropy fuzzy clustering
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Recycling of waste E-cigarette butts as engineered pelletized fibres for sustainable stone mastic asphalt 被引量:1
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作者 Yunfei Guo Piergiorgio Tataranni +3 位作者 Giulia Tarsi Filippo Balzano Jiasheng Dai Cesare Sangiorgi 《Journal of Road Engineering》 2024年第4期468-477,共10页
The disposal of discarded E-cigarette butts(E-CBs) presents significant environmental challenges due to their detrimental impacts on ecosystems. To find an environmentally sustainable method for managing this waste, t... The disposal of discarded E-cigarette butts(E-CBs) presents significant environmental challenges due to their detrimental impacts on ecosystems. To find an environmentally sustainable method for managing this waste, the potential for recycling E-CBs in asphalt pavements was investigated in this study. By focusing on the two primary components of E-CBs, namely cellulose fibre and polylactic acid(PLA), this research introduced a novel approach for recycling E-CBs in stone mastic asphalt(SMA) as a fibre additive in engineered pellet form. The prepared fibre pellets were directly added to aggregates to produce the SMA mixture. The resulting mixtures underwent a comprehensive evaluation through a series of standardized laboratory tests, including assessments of volumetric properties, indirect tensile strength(ITS), stiffness modulus, moisture susceptibility, and rutting resistance. The results were compared with SMA mixtures containing conventional cellulose fibres. Additionally, to examine the potential influence of PLA, a third mixture was prepared, incorporating both cellulose fibre and PLA. The findings indicate that the SMA using pelletized fibre can satisfy the technical specifications regarding the tests performed in this study, showing higher ITS and rutting resistance compared to the reference mixture. Moreover, the incorporation of PLA plastic reduced air void content and improved tensile strength, stiffness, and rutting resistance. This study highlights the potential for recycling E-CBs in asphalt mixtures, offering technical support for further development of sustainable recycling methods for this waste. 展开更多
关键词 Waste cigarette butts Pelletized fibres PLA plastic SMA Sustainable bituminous mixtures
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The effect of the fibre orientation of electrospun scaffolds on the matrix production of rabbit annulus fibrosus-derived stem cells 被引量:16
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作者 Chen Liu Caihong Zhu +4 位作者 Jun Li Pinghui Zhou Min Chen Huilin Yang Bin Li 《Bone Research》 SCIE CAS CSCD 2015年第2期112-120,共9页
Annulus fibrosus (AF) tissue engineering has recently received increasing attention as a treatment for intervertebral disc 0VD) degeneration; however, such engineering remains challenging because of the remarkable ... Annulus fibrosus (AF) tissue engineering has recently received increasing attention as a treatment for intervertebral disc 0VD) degeneration; however, such engineering remains challenging because of the remarkable complexity of AF tissue. In order to engineer a functional AF replacement, the fabrication of cell-scaffold constructs that mimic the cellular, biochemical and structural features of native AF tissue is critical. In this study, we fabricated aligned fibroua polyurethane scaffolds using an electrospinning technique and used them for culturing AF-derived-stem/progenitor cells (AFSCs). Random fibrous scaffolds, also prepared via electrospinningy were used as a control. We compared the morphology, proliferation, gene expression and matrix production of AFSCs on aligned scaffolds and random scaffolds. There was no apparent difference in the attachment or proliferation of cells cultured on aligned scaffolds and random scaffolds. However, compared to cells on random scaffolds, the AFSCs on aligned scaffolds were more elongated and better aligned, and they exhibited higher gene expression and matrix production of coUagen-I and aggrecan. The gene expression and protein production of coUagen-II did not appear to differ between the two groups. Together, these findings indicate that aligned fibrous scaffolds may provide a favourable microenvironment for the differentiation of AFSCs into cells similar to outer AF cells, which predominantly produce collagen-I matrix. 展开更多
关键词 The effect of the fibre orientation of electrospun scaffolds on the matrix production of rabbit annulus fibrosus-derived stem cells FIGURE STEM
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Comparative impact behaviours of ultra high performance concrete columns reinforced with polypropylene vs steel fibres
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作者 Thong M.Pham Harrison Hyde +4 位作者 Maw K.Kaung Yan Zhuge Duong T.Tran Des Vlietstra Tung M.Tran 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第10期138-153,共16页
Polypropylene(PP) fibres have primarily used to control shrinkage cracks or mitigate explosive spalling in concrete structures exposed to fire or subjected to impact/blast loads, with limited investigations on capacit... Polypropylene(PP) fibres have primarily used to control shrinkage cracks or mitigate explosive spalling in concrete structures exposed to fire or subjected to impact/blast loads, with limited investigations on capacity improvement. This study unveils the possibility of using PP micro-fibres to improve the impact behaviour of fibre-reinforced ultra-high-performance concrete(FRUHPC) columns. Results show that the addition of fibres significantly improves the impact behaviour of FRUHPC columns by shifting the failure mechanism from brittle shear to favourable flexural failure. The addition of steel or PP fibres affected the impact responses differently. Steel fibres considerably increased the peak impact force(up to 18%) while PP micro-fibres slightly increased the peak(3%-4%). FRUHPC significantly reduced the maximum midheight displacement by up to 30%(under 20°impact) and substantially improved the displacement recovery by up to 100%(under 20° impact). FRUHPC with steel fibres significantly improved the energy absorption while those with PP micro-fibres reduced the energy absorption, which is different from the effect of PP-macro fibre reported in the literature. The optimal fibre content for micro-PP fibres is 1% due to its minimal fibre usage and low peak and residual displacement. This study highlights the potential of FRUHPC as a promising material for impact-resistant structures by creating a more favourable flexural failure mechanism, enhancing ductility and toughness under impact loading, and advancing the understanding of the role of fibres in structural performance. 展开更多
关键词 Ultra high-performance concrete Steel fibre Polypropylene micro-fibre fibre volume fraction Impact loading Pendulum tests COLUMNS
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A Review on Coir Fibre,Coir Fibre Reinforced Polymer Composites and Their Current Applications
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作者 Chioma Ifeyinwa Madueke Okwunna Maryjane Ekechukwu Funsho Olaitan Kolawole 《Journal of Renewable Materials》 EI CAS 2024年第12期2017-2047,共31页
Coir fibre has generated much interest as an eco-friendly,sustainable fibre with low density.This review findings show that coir fibres are abundant,with an average global annual production of 1019.7×103 tonnes,w... Coir fibre has generated much interest as an eco-friendly,sustainable fibre with low density.This review findings show that coir fibres are abundant,with an average global annual production of 1019.7×103 tonnes,with about 63%of this volume produced from India.Extraction of coir has been carried out through water retting.However,the retting period has been limited to 4–10 months.The lignin content of coir is more than 60%higher than that of other natural fibres;hence,coir could double as a source of lignin for other applications.The diameter of coir fibres varies from 0.006 mm(Vietnam)to 0.577 mm(Thailand),and their tensile strength ranges from 68.4 MPa(Tanzania)to 343 MPa(Vietnam).Coir fibres from Vietnam and India exhibit the highest elongation at break(63.8%)and the highest Young’s modulus(6 GPa),respectively.More than 50%of the researchers within the scope of the reviewed studies employed the hand layup(HLU)manufacturing method with an epoxy resin matrix.Fibre volume fractions used range between 10%–65%.An outstanding tensile strength of 62.92 MPa at 49%fibre volume fraction was recorded for coir composites where the fibres were unidirectionally oriented and stacked in three layers,manufactured using epoxy resin and the HLU technique.Only a few works have been done using Vacuum-assisted resin transfer moulding(VARTM).The curing of composites was mostly carried out at an unspecified temperature and duration.A defined fibre volume fraction with a defined mixing and mixing time of the matrix is imperative.The degree of uniform dispersity of the fibres in the matrix is lacking.The creep behaviour of coir composites,coating and wider treatment parameters need to be explored for advanced applications.Recent findings on the applications of coir composites are equally highlighted. 展开更多
关键词 COIR natural fibre COMPOSITES mechanical properties POLYMER
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