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
Polypropylene fibres and three sizes of steel fibres reinforced concrete are discussed. The total fibres content ranges from 0 4%-0 95% by volume of concrete. A four point bending test is adopted on the notched pris...Polypropylene fibres and three sizes of steel fibres reinforced concrete are discussed. The total fibres content ranges from 0 4%-0 95% by volume of concrete. A four point bending test is adopted on the notched prisms with the size of 100?mm×100?mm×500?mm to investigate the effect of hybrid fibres on crack arresting. The research results show that there is a positive synergy effect between large steel fibres and polypropylene fibres on the load bearing capacity in the small displacement range. But this synergy effect disappears in the large displacement range. The large and strong steel fibre is better than soft polypropylene fibre and small steel fibre in the aspect of energy absorption capacity in the large displacement range. The static usage limitation for the hybrid fibres concrete with “wide peak' or “multi peaks' load CMOD pattern should be carefully selected. The ultimate load bearing capacity and the crack width or CMOD at this load level should be jointly considered.展开更多
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
Archroma becomes the exclusive global distributor of Fibre52®'s patented chemistry-advancing a new standard in sustainable processing.Combined with Archroma's AVITERA®SE dyes,the partnership delivers...Archroma becomes the exclusive global distributor of Fibre52®'s patented chemistry-advancing a new standard in sustainable processing.Combined with Archroma's AVITERA®SE dyes,the partnership delivers the industry's most resource-efficient bleach-and-dye sys-tems.Archroma,a leading global specialty chemicals company committed to sus-tainable innovation,and Innovo Fiber LLC,owner of the patented Fibre52®system,today announced an exclusive global dis-tribution partnership to expand the reach of Fibre52®'s proven low-temperature,bleaching technology with innovative dyeing application to textile mills and brands worldwide.展开更多
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
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
Based on the rate equations describing the erbium-doped fluoride glass （ZBLAN） fibre lasers with different pumping configurations being taken into account, this paper presents theoretical calculations related to the...Based on the rate equations describing the erbium-doped fluoride glass （ZBLAN） fibre lasers with different pumping configurations being taken into account, this paper presents theoretical calculations related to the dynamic population density and the operation performance of a high power mid-infrared all-fibre erbium-doped ZBLAN fibre laser. It shows that the ground-state absorption, excited-state absorption and energy-transfer-upconversion processes co-exist and produce a population balance, causing the laser to operate stably at a continuous wave state. A good agreement between the theoretical results and recent experimental measurement is obtained. Furthermore, the laser structure parameters including fibre length, reflectance of output fibre Bragg grating and pumping configurations are quantitatively optimised to achieve the best performance. The results show, as expected, that the slope efficiency of the fibre laser can be improved significantly through optimisation, which then provides an important guide for the design of high-performance mid-infrared erbium-doped ZBLAN fibre lasers.展开更多
This paper presents the development process relating to the conceptual design of glass/renewable natural fibrereinforced polymer hybrid composite motorcycle side cover.Motorcycle side cover is a component frequently m...This paper presents the development process relating to the conceptual design of glass/renewable natural fibrereinforced polymer hybrid composite motorcycle side cover.Motorcycle side cover is a component frequently made from plastic or steel that functions on covering the motorcycle parts,components and systems such as frame,battery,electrical systems and mechanical systems.Function Analysis Systems Techniques(FAST)is used to identify the functions of motorcycle side cover.The right-side cover of motorcycle model SYM E-Bonus 110 has been physically studied to identify the competitive benchmarking criteria.The functions and competitive benchmarking criteria are then compiled and integrated with the environmental requirements to identify the Product Design Specifications(PDS).The coir fibre has been selected from six identified dominant renewable natural fibre used for automotive component through integration of Ranking Method and Quality Based Selection(QBS).Then the polypropylene matrix is selected after shortlisting the existing thermoplastic that is used with coir fibre and has high suitability for injection moulding manufacturing.The polypropylene matrix is then evaluated using Weighted Evaluation Matrix(WEM)by comparing to benchmark material which is Acrylonitrile Butadiene Styrene(ABS).After that,the conceptual design development of glass/renewable coir fibre-reinforced polypropylene motorcycle side cover is carried out using an integrated Theory of Inventive Problem Solving(TRIZ)and Morphological Chart,followed by final conceptual design selection using integration of Pugh Scoring Method and QBS.The conceptual design development intended on improving the biodegradability to reduce pollution to the environment.However,the usage of glass/coir fibre-reinforced polypropylene hybrid composite may increase the weight due to higher density.Four innovative design concepts have been developed and the selected final concept design has the most minimum number of ribs and minimum thickness with the same ratio of glass fibre and natural fibre composition.展开更多
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
Toddy palm fruit have an apparent density below 0.8 g/cm³and offer an interesting lightweight construction potential in polylactide(PLA)composites reinforced with 37 mass-%fibres.Single fibre bundles show similar...Toddy palm fruit have an apparent density below 0.8 g/cm³and offer an interesting lightweight construction potential in polylactide(PLA)composites reinforced with 37 mass-%fibres.Single fibre bundles show similar mechanical properties compared with coir:tensile strength of 240 MPa,Young´s modulus of 3.8 GPa and an elongation at break of 31%.However,density and diameter(~50μm)of fruit fibre bundles are significantly lower.The compression moulded composites have a density of 0.9 g/cm³and achieved an unnotched Charpy impact strength of 12 kJ/m^(2),a tensile strength of 25 MPa,Young’s modulus of 1.9 GPa and an elongation at break of 9%.Due to the high porosity of the composites and the different stress-strain behaviour of fibre and matrix the fibre-reinforcement potential could not be fully used.Maximum stress of the composite was reached at the elongation at break of the PLA-matrix(~2%)while the fibre achieved its maximum stress at an elongation of~31%.After reaching the maximum stress of the composite,the fibres were pulled out from the matrix with low energy absorption,resulting in a decrease in stress and a limited reinforcement potential.Additionally,the study investigates whether an insect attack by the Asian fruit fly on the mesocarp has a significant influence on the mechanical fibre characteristics.The results have shown that only the rough surface of the fibre bundles is smoothed by insect infestation.The mechanical properties were not significantly affected.For this reason insect-infested fruits of the toddy palm,which are no longer suitable for food production,can be used for the production of sustainable composite materials.展开更多
The yttrium as a sintering aid was introduced into polycarbosilane（PCS） to prepare yttrium-containing PCS（PYCS）.Two types of yttrium-containing SiC fibres,the SiC（OY） fibres and the SiC（Y） fibres,were fabricat...The yttrium as a sintering aid was introduced into polycarbosilane（PCS） to prepare yttrium-containing PCS（PYCS）.Two types of yttrium-containing SiC fibres,the SiC（OY） fibres and the SiC（Y） fibres,were fabricated with PYCS.The structural evolution and the associated properties on changing from SiC（OY） to SiC（Y） fibres during the sintering process were studied.The chemical composition of the SiC（OY） fibres is SiC1.53O0.22Y0.005 with an amorphous structure.The composition of SiC（Y） fibres is SiC1.23O0.05Y0.005.The fibres are composed of a large number of β-SiC crystallites with a size of 50 nm and a small amount of α-SiC crystalline.The tensile strength and fracture toughness of the SiC（OY） fibres are 2.25 GPa and 2.37 MPa·m1/2,respectively,and 1.61 GPa,1.91 MPa·m1/2,respectively for SiC（Y） fibres.The SiC（Y） fibres have a higher thermal stability than the SiC（OY） fibres.展开更多
The creep performance of basalt fibre（BF）reinforced in asphalt mortar under uniaxial compressive loadings is investigated. The samples of basalt fibre asphalt mortar（BFAM） with different BF mass fractions（0. 1%,0...The creep performance of basalt fibre（BF）reinforced in asphalt mortar under uniaxial compressive loadings is investigated. The samples of basalt fibre asphalt mortar（BFAM） with different BF mass fractions（0. 1%,0. 2%, and 0. 5%） and without BF in asphalt mixture are prepared, and then submitted for the compressive strength test and corresponding creep test at a high in-service temperature.Besides, numerical simulations in finite element ABAQUS software were conducted to model the compressive creep test of mortar materials, where the internal structure of the fibre mortar was assumed to be a two-component composite material model such as fibre and mortar matrix. Finally, the influence factors of rheological behaviors of BFAM are further analyzed. Results indicate that compared to the control sample, the compressive strength of BFAM samples has a significant increase, and the creep and residual deformation are decreased. However, it also shows that the excessive fibre, i.e. with the BF content of 0. 5%, is unfavorable to the high-temperature stability of the mortar. Based on the analysis results, the prediction equations of parameters of the Burgers constitutive model for BFAM are proposed by considering the fibre factors.展开更多
The reflected optical caustics method is applied to study dynamic fracture problems in hardened cement paste. First both the unreinforced cement paste and the glass fibres reinforced cement paste specimens were fabric...The reflected optical caustics method is applied to study dynamic fracture problems in hardened cement paste. First both the unreinforced cement paste and the glass fibres reinforced cement paste specimens were fabricated and the reflective coating on the surface of the specimen was prepared. Secondly the crack path and the shadow spot patterns during the crack propagation process for the two specimens were recorded by using a multi-spark high speed camera.Thirdly some dynamic parameters of two cement paste specimens including crack onset time the dynamic stress intensity factor and crack growth velocity were determined and analyzed comparatively.This indicates that the glass fibres can improve the fracture resistance and delay fracture time.These results will play an important role in evaluating the dynamic fracture properties of cement paste.展开更多
The effects of fibre/matrix bonding, fabric density, fibre volume fraction and bundle size on microstructure, mechanical properties and failure mechanisms in carbon fibre reinforced composites （plastic and carbon mat...The effects of fibre/matrix bonding, fabric density, fibre volume fraction and bundle size on microstructure, mechanical properties and failure mechanisms in carbon fibre reinforced composites （plastic and carbon matrix） have been investigated. The microstructure of unloaded and cracked samples was studied by optical microscopy and scanning electron microscopy （SEM）, respectively whereas the mechanical behaviour was examined by 3- point bending experiments. Exclusively one type of experimental resole type phenolic resin was applied. A strong fibre/matrix bonding, which is needed for high strength of carbon fibre reinforced plastic （CFRP） materials leads to severe composite damages during the pyrolysis resulting in low strength, brittle failure and a very low utilisation of the fibres strain to failure in C/C composites. Inherent fabric parameters such as an increasing fabric density or bundle size or a reduced fibre volume fraction introduce inhomogenities to the CFRP＇s microstructure. Results are lower strength and stiffness whereas the strain to failure increases or remains unchanged. Toughness is almost not affected. In C/C composites inhomogenities due to a reduced bundle size reduce strain to failure, strength, stiffness and toughness. Vice versa a declining fibre volume fraction leads to exactly the opposite behaviour. Increasing the fabric density （weight per unit area） causes similar effects as in CFRPs.展开更多
To obtain the stable operation of erbium-doped fibre laser, the simple and ideal technology is adopted by use of the erbium doped polarization maintaining fibre （EDPMF）. The design criteria of the Panda-type EDPMF a...To obtain the stable operation of erbium-doped fibre laser, the simple and ideal technology is adopted by use of the erbium doped polarization maintaining fibre （EDPMF）. The design criteria of the Panda-type EDPMF are presented, which take into account the cutoff wavelength, mode field diameter, modal birefringence and background loss. Four groups of optimum structural paramcter combinations are determined in terms of the design criteria. Two kinds of the Panda-type EDPMFs are selected to be fabricated. The fabrication process and the parameter control of the Panda-type EDPMFs are presented in detail. Their refractive index profiles, birefringence and absorption spectra are experimentally investigated. The absorption coefficient of the EDPMF, whose core is co-doped with Bi, Ga, A1 and Ge, is about 57.9dB/m at 1.53μm. Co-doping Bi, Ga and A1 can greatly increase the erbium concentration in the silica-based fibre. The high birefringence is obtained for the Panda-type EDPMF. The group birefringence of the EDPMF, whose outer cladding diameter is 125 μm, is about 4.8 × 10%^-4.展开更多
Polylactic acid(PLA)possesses good mechanical and biodegradability properties which make it a suitable material for polymer composites whereas brittleness and high costs limit its utilization in various applications.T...Polylactic acid(PLA)possesses good mechanical and biodegradability properties which make it a suitable material for polymer composites whereas brittleness and high costs limit its utilization in various applications.The reinforcement of natural fibres with biopolymers has been formed to be an efficient technique to develop composites having the ability to be fully biodegradable.This study concerns with the incorporation of various percentages of untreated and alkali-treated Coir Fibres(CF)and pineapple leaf fibres(PALF)in PLA biocomposites and characterizations of flexural,morphological and dynamic mechanical properties.Flexural properties showed that the treated C1P1 hybrid composites(C1P1A)displayed highest flexural strength(35.81 MPa)and modulus(5.28 GPa)among all hybrid biocomposites.Scanning Electron Microscopy(SEM)revealed a behaviour of fibre-matrix adhesion in untreated treated biocomposites.SEM observation revealed good dispersion of the fillers in PLA.Dynamic mechanical analysis revealed that C1P1A showed highest glass transition temperature(Tg)and storage modulus(E')while untreated C3P7 displayed the least Tg and E'.Overall findings showed that alkali-treated hybrid biocomposites(CF/PALF/PLA)especially C1P1A have improved flexural properties,dynamic and morphological properties over untreated biocomposites.Success of these findings will provide attracting consideration of these hybrid biocomposites for various lightweight uses in a broad selection of industrial applications such as biomedical sectors,automobile,construction,electronics equipment,and hardware tools.展开更多
This paper aims at studying the effect of recycling on the static and dynamic properties of short alfa fibre reinforced polypropylene.For this purpose,alfa fibres reinforced composites were elaborated by an injection ...This paper aims at studying the effect of recycling on the static and dynamic properties of short alfa fibre reinforced polypropylene.For this purpose,alfa fibres reinforced composites were elaborated by an injection moulding process and were subjected to different mechanical recycling cycles.Then,non-recycled and recycled materials were subjected to static tests and Dynamic Mechanical Analysis(DMA)to evaluate the effect of recycling on their behaviour.Besides,the effects of alkali and salt water treatments on the static and dynamic properties of the alfa composite were also investigated.The obtained results show that tensile and flexural properties of alfa fibres reinforced composites decrease during recycling cycles.Moreover,the recycling induces a drop in the storage modulus and enhances the loss factor of these composites.The composites with alfa fibre especially the alkali treated composite show the same resistance to recycling as composites with hemp fibres.Further,SEM observations indicate a decrease in the fibres dimension with the recycling cycles,especially for alfa fibres,which can explain the decrease in the properties of the alfa composite during recycling operations.展开更多
基金funding support from JSPS KAKENHI(Grant Nos.21H01593 and 21K18794)through Tetsuya KogureThis work was also partially supported by the Sasakawa Scientific Research Grant(2023e2026)from the Japan Science Society(JSS)through Ashis Acharya.
文摘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.
文摘Polypropylene fibres and three sizes of steel fibres reinforced concrete are discussed. The total fibres content ranges from 0 4%-0 95% by volume of concrete. A four point bending test is adopted on the notched prisms with the size of 100?mm×100?mm×500?mm to investigate the effect of hybrid fibres on crack arresting. The research results show that there is a positive synergy effect between large steel fibres and polypropylene fibres on the load bearing capacity in the small displacement range. But this synergy effect disappears in the large displacement range. The large and strong steel fibre is better than soft polypropylene fibre and small steel fibre in the aspect of energy absorption capacity in the large displacement range. The static usage limitation for the hybrid fibres concrete with “wide peak' or “multi peaks' load CMOD pattern should be carefully selected. The ultimate load bearing capacity and the crack width or CMOD at this load level should be jointly considered.
文摘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.
文摘Archroma becomes the exclusive global distributor of Fibre52®'s patented chemistry-advancing a new standard in sustainable processing.Combined with Archroma's AVITERA®SE dyes,the partnership delivers the industry's most resource-efficient bleach-and-dye sys-tems.Archroma,a leading global specialty chemicals company committed to sus-tainable innovation,and Innovo Fiber LLC,owner of the patented Fibre52®system,today announced an exclusive global dis-tribution partnership to expand the reach of Fibre52®'s proven low-temperature,bleaching technology with innovative dyeing application to textile mills and brands worldwide.
基金supported by the National Nature Science Foundation of China(No.52175440)the Aeronautics Science Foundation of China(No.2023Z049076001)+3 种基金the Science and Technology Innovation Fund of Shanghai Aerospace(No.SAST2022-058)the Open Fund of State Key Laboratory of Mechanical Transmissions(No.SKLMT-MSKFKT-202202)the Key R&D Program of Zhejiang Province(No.2023C01058)the Experimental Technique Project of Zhejiang University(No.SYBJS202302),China.
文摘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.
基金funded under the Collaborative Research Initiative Grant Scheme(C-RIGS),grant number C-RIGS24-016-0022 from IIUM.
文摘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.
基金supported by the China Postdoctoral Science Foundation (Grant No. 20090451417)the China Postdoctoral Science Special Foundation (Grant No. 201003693)+1 种基金the Fundamental Research Funds for the Central Universities of China (Grant No. ZYGX2009J053)the National Natural Science Foundation of China (Grant No. 60736038)
文摘Based on the rate equations describing the erbium-doped fluoride glass （ZBLAN） fibre lasers with different pumping configurations being taken into account, this paper presents theoretical calculations related to the dynamic population density and the operation performance of a high power mid-infrared all-fibre erbium-doped ZBLAN fibre laser. It shows that the ground-state absorption, excited-state absorption and energy-transfer-upconversion processes co-exist and produce a population balance, causing the laser to operate stably at a continuous wave state. A good agreement between the theoretical results and recent experimental measurement is obtained. Furthermore, the laser structure parameters including fibre length, reflectance of output fibre Bragg grating and pumping configurations are quantitatively optimised to achieve the best performance. The results show, as expected, that the slope efficiency of the fibre laser can be improved significantly through optimisation, which then provides an important guide for the design of high-performance mid-infrared erbium-doped ZBLAN fibre lasers.
文摘This paper presents the development process relating to the conceptual design of glass/renewable natural fibrereinforced polymer hybrid composite motorcycle side cover.Motorcycle side cover is a component frequently made from plastic or steel that functions on covering the motorcycle parts,components and systems such as frame,battery,electrical systems and mechanical systems.Function Analysis Systems Techniques(FAST)is used to identify the functions of motorcycle side cover.The right-side cover of motorcycle model SYM E-Bonus 110 has been physically studied to identify the competitive benchmarking criteria.The functions and competitive benchmarking criteria are then compiled and integrated with the environmental requirements to identify the Product Design Specifications(PDS).The coir fibre has been selected from six identified dominant renewable natural fibre used for automotive component through integration of Ranking Method and Quality Based Selection(QBS).Then the polypropylene matrix is selected after shortlisting the existing thermoplastic that is used with coir fibre and has high suitability for injection moulding manufacturing.The polypropylene matrix is then evaluated using Weighted Evaluation Matrix(WEM)by comparing to benchmark material which is Acrylonitrile Butadiene Styrene(ABS).After that,the conceptual design development of glass/renewable coir fibre-reinforced polypropylene motorcycle side cover is carried out using an integrated Theory of Inventive Problem Solving(TRIZ)and Morphological Chart,followed by final conceptual design selection using integration of Pugh Scoring Method and QBS.The conceptual design development intended on improving the biodegradability to reduce pollution to the environment.However,the usage of glass/coir fibre-reinforced polypropylene hybrid composite may increase the weight due to higher density.Four innovative design concepts have been developed and the selected final concept design has the most minimum number of ribs and minimum thickness with the same ratio of glass fibre and natural fibre composition.
基金the financial support from Australian Research Council(ARC)(Grant No.DP220100307).
文摘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.
基金funded within the framework of the BMBF exchange project“Thai-German Agro-based Fibre Exchange Programme-Sustainable Development:From Plant to Product(Acronym:AgroFibre)”under the registration number 01DP15016.
文摘Toddy palm fruit have an apparent density below 0.8 g/cm³and offer an interesting lightweight construction potential in polylactide(PLA)composites reinforced with 37 mass-%fibres.Single fibre bundles show similar mechanical properties compared with coir:tensile strength of 240 MPa,Young´s modulus of 3.8 GPa and an elongation at break of 31%.However,density and diameter(~50μm)of fruit fibre bundles are significantly lower.The compression moulded composites have a density of 0.9 g/cm³and achieved an unnotched Charpy impact strength of 12 kJ/m^(2),a tensile strength of 25 MPa,Young’s modulus of 1.9 GPa and an elongation at break of 9%.Due to the high porosity of the composites and the different stress-strain behaviour of fibre and matrix the fibre-reinforcement potential could not be fully used.Maximum stress of the composite was reached at the elongation at break of the PLA-matrix(~2%)while the fibre achieved its maximum stress at an elongation of~31%.After reaching the maximum stress of the composite,the fibres were pulled out from the matrix with low energy absorption,resulting in a decrease in stress and a limited reinforcement potential.Additionally,the study investigates whether an insect attack by the Asian fruit fly on the mesocarp has a significant influence on the mechanical fibre characteristics.The results have shown that only the rough surface of the fibre bundles is smoothed by insect infestation.The mechanical properties were not significantly affected.For this reason insect-infested fruits of the toddy palm,which are no longer suitable for food production,can be used for the production of sustainable composite materials.
基金Projects (51175444,50532010) supported by the National Natural Science Foundation of ChinaProject (2011121002) supported by the Fundamental Research Funds for the Central Universities, ChinaProject (2009J1009) supported by Scientific and Technological Innovation Platform of Fujian Province,China
文摘The yttrium as a sintering aid was introduced into polycarbosilane（PCS） to prepare yttrium-containing PCS（PYCS）.Two types of yttrium-containing SiC fibres,the SiC（OY） fibres and the SiC（Y） fibres,were fabricated with PYCS.The structural evolution and the associated properties on changing from SiC（OY） to SiC（Y） fibres during the sintering process were studied.The chemical composition of the SiC（OY） fibres is SiC1.53O0.22Y0.005 with an amorphous structure.The composition of SiC（Y） fibres is SiC1.23O0.05Y0.005.The fibres are composed of a large number of β-SiC crystallites with a size of 50 nm and a small amount of α-SiC crystalline.The tensile strength and fracture toughness of the SiC（OY） fibres are 2.25 GPa and 2.37 MPa·m1/2,respectively,and 1.61 GPa,1.91 MPa·m1/2,respectively for SiC（Y） fibres.The SiC（Y） fibres have a higher thermal stability than the SiC（OY） fibres.
基金The National Natural Science Foundation of China(No.51108082)
文摘The creep performance of basalt fibre（BF）reinforced in asphalt mortar under uniaxial compressive loadings is investigated. The samples of basalt fibre asphalt mortar（BFAM） with different BF mass fractions（0. 1%,0. 2%, and 0. 5%） and without BF in asphalt mixture are prepared, and then submitted for the compressive strength test and corresponding creep test at a high in-service temperature.Besides, numerical simulations in finite element ABAQUS software were conducted to model the compressive creep test of mortar materials, where the internal structure of the fibre mortar was assumed to be a two-component composite material model such as fibre and mortar matrix. Finally, the influence factors of rheological behaviors of BFAM are further analyzed. Results indicate that compared to the control sample, the compressive strength of BFAM samples has a significant increase, and the creep and residual deformation are decreased. However, it also shows that the excessive fibre, i.e. with the BF content of 0. 5%, is unfavorable to the high-temperature stability of the mortar. Based on the analysis results, the prediction equations of parameters of the Burgers constitutive model for BFAM are proposed by considering the fibre factors.
基金The Ph.D.Programs Foundation of Ministry of Education of China(No.20120023120020)the National Natural Science Foundation of China(No.51404273)
文摘The reflected optical caustics method is applied to study dynamic fracture problems in hardened cement paste. First both the unreinforced cement paste and the glass fibres reinforced cement paste specimens were fabricated and the reflective coating on the surface of the specimen was prepared. Secondly the crack path and the shadow spot patterns during the crack propagation process for the two specimens were recorded by using a multi-spark high speed camera.Thirdly some dynamic parameters of two cement paste specimens including crack onset time the dynamic stress intensity factor and crack growth velocity were determined and analyzed comparatively.This indicates that the glass fibres can improve the fracture resistance and delay fracture time.These results will play an important role in evaluating the dynamic fracture properties of cement paste.
文摘The effects of fibre/matrix bonding, fabric density, fibre volume fraction and bundle size on microstructure, mechanical properties and failure mechanisms in carbon fibre reinforced composites （plastic and carbon matrix） have been investigated. The microstructure of unloaded and cracked samples was studied by optical microscopy and scanning electron microscopy （SEM）, respectively whereas the mechanical behaviour was examined by 3- point bending experiments. Exclusively one type of experimental resole type phenolic resin was applied. A strong fibre/matrix bonding, which is needed for high strength of carbon fibre reinforced plastic （CFRP） materials leads to severe composite damages during the pyrolysis resulting in low strength, brittle failure and a very low utilisation of the fibres strain to failure in C/C composites. Inherent fabric parameters such as an increasing fabric density or bundle size or a reduced fibre volume fraction introduce inhomogenities to the CFRP＇s microstructure. Results are lower strength and stiffness whereas the strain to failure increases or remains unchanged. Toughness is almost not affected. In C/C composites inhomogenities due to a reduced bundle size reduce strain to failure, strength, stiffness and toughness. Vice versa a declining fibre volume fraction leads to exactly the opposite behaviour. Increasing the fabric density （weight per unit area） causes similar effects as in CFRPs.
文摘To obtain the stable operation of erbium-doped fibre laser, the simple and ideal technology is adopted by use of the erbium doped polarization maintaining fibre （EDPMF）. The design criteria of the Panda-type EDPMF are presented, which take into account the cutoff wavelength, mode field diameter, modal birefringence and background loss. Four groups of optimum structural paramcter combinations are determined in terms of the design criteria. Two kinds of the Panda-type EDPMFs are selected to be fabricated. The fabrication process and the parameter control of the Panda-type EDPMFs are presented in detail. Their refractive index profiles, birefringence and absorption spectra are experimentally investigated. The absorption coefficient of the EDPMF, whose core is co-doped with Bi, Ga, A1 and Ge, is about 57.9dB/m at 1.53μm. Co-doping Bi, Ga and A1 can greatly increase the erbium concentration in the silica-based fibre. The high birefringence is obtained for the Panda-type EDPMF. The group birefringence of the EDPMF, whose outer cladding diameter is 125 μm, is about 4.8 × 10%^-4.
基金gratitude to Institute of Tropical Forestry and Forest Products(INTROP),Universiti Putra Malaysia for supporting the funding of research through Grant No:6369108funded by Researchers Supporting Project number(RSP-2021/117),King Saud University,Riyadh,Saudi Arabia.
文摘Polylactic acid(PLA)possesses good mechanical and biodegradability properties which make it a suitable material for polymer composites whereas brittleness and high costs limit its utilization in various applications.The reinforcement of natural fibres with biopolymers has been formed to be an efficient technique to develop composites having the ability to be fully biodegradable.This study concerns with the incorporation of various percentages of untreated and alkali-treated Coir Fibres(CF)and pineapple leaf fibres(PALF)in PLA biocomposites and characterizations of flexural,morphological and dynamic mechanical properties.Flexural properties showed that the treated C1P1 hybrid composites(C1P1A)displayed highest flexural strength(35.81 MPa)and modulus(5.28 GPa)among all hybrid biocomposites.Scanning Electron Microscopy(SEM)revealed a behaviour of fibre-matrix adhesion in untreated treated biocomposites.SEM observation revealed good dispersion of the fillers in PLA.Dynamic mechanical analysis revealed that C1P1A showed highest glass transition temperature(Tg)and storage modulus(E')while untreated C3P7 displayed the least Tg and E'.Overall findings showed that alkali-treated hybrid biocomposites(CF/PALF/PLA)especially C1P1A have improved flexural properties,dynamic and morphological properties over untreated biocomposites.Success of these findings will provide attracting consideration of these hybrid biocomposites for various lightweight uses in a broad selection of industrial applications such as biomedical sectors,automobile,construction,electronics equipment,and hardware tools.
文摘This paper aims at studying the effect of recycling on the static and dynamic properties of short alfa fibre reinforced polypropylene.For this purpose,alfa fibres reinforced composites were elaborated by an injection moulding process and were subjected to different mechanical recycling cycles.Then,non-recycled and recycled materials were subjected to static tests and Dynamic Mechanical Analysis(DMA)to evaluate the effect of recycling on their behaviour.Besides,the effects of alkali and salt water treatments on the static and dynamic properties of the alfa composite were also investigated.The obtained results show that tensile and flexural properties of alfa fibres reinforced composites decrease during recycling cycles.Moreover,the recycling induces a drop in the storage modulus and enhances the loss factor of these composites.The composites with alfa fibre especially the alkali treated composite show the same resistance to recycling as composites with hemp fibres.Further,SEM observations indicate a decrease in the fibres dimension with the recycling cycles,especially for alfa fibres,which can explain the decrease in the properties of the alfa composite during recycling operations.
