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When providing care, to protect a part of the human body against resins and plas ters for certain time, it is necessary to use a circular knitted band in cotton as a raw material. The generating of Cotton fiber fly throughout the knitting process is due to interactions of frictional surfaces with the hairiness of ring spun yarn. During the manufacture short fibers are formed in the machine device, this problem is more important with the use of cotton yarns. In this research paper, the short fibers formation on circular knitting machines from spun yarns such as cotton is investigated The knitting conditions consist of; yarn tension, yarn feeding speed and the angle contact of the yarn with guides and needles. The results obtained illustrate the effect of yarn tension on the short fibers deposit caused by the combination of yarn friction with the knitting elements.

Amidst a world of never-ending waste production and waste disposal crises, scientists have been working their ways to come up with solutions to serve the earth better. Two such commonly found trashes deteriorating the environment are glass and tin can waste. This study aims to investigate the comparative suitability of response surface methodology (RSM) and artificial neural network (ANN) in predicting the mechanical strength of concrete prepared with fine glass aggregate (GFA) and condensed milk can (tin) fibers (CMCF). An experimental scheme has been designed in this study with two input variables as GFA and CMCF, and two output variables as compressive and splitting tensile strength. The results show that both variables influenced the compressive and splitting tensile strength of concrete at 7, 28, and 56 days (p

Statement of problem Various strategies have been proposed to reduce the cement space of foundation restorations for endodontically treated teeth. However, they may add more operative steps, or the dentist must keep different sizes of drills and posts in stock. A 2-piece universal adjustable post system has been developed to overcome this problem, but whether the system has acceptable fatigue survival performance is unclear. Purpose The purpose of this in vitro study was to evaluate the fatigue survival and stress distribution of endodontically treated teeth without a ferrule and restored with different glass fiber post strategies versus a recently introduced universal 2-piece fiber post system. Material and methods Bovine incisor roots were randomly assigned to 3 groups as per the post used (n=13): adapted glass fiber post with post space preparation of the same size, composite resin-custom glass fiber post (CTM), and universal 2-piece glass fiber-reinforced composite resin post (UNI). The posts were adhesively luted, the composite resin core was added, and a composite resin crown was produced with computer-aided design and computer-aided manufacturing (CAD-CAM), and then adhesively luted to each core. A fatigue test was performed with the stepwise stress method (10 000 cycles/step; 20 Hz; load=100 N to 750 N; step=50 N) until fracture, and the failure mode analyzed. The stress distribution was evaluated by finite element analysis with the maximum principal stress criteria by following the parameters of the in vitro test. The solids were considered homogeneous, linear, and isotropic, except for the glass fiber post (orthotropic), and a load of 450 N at 30 degrees was applied. The fatigue failure load and the number of cycles for failure were analyzed with Kaplan-Meier and Mantel-Cox (log rank test) (α=.05). The finite element analysis results were analyzed with colorimetric graphs. Results The highest fatigue failure load and the number of cycles for failure were found in the UNI system, whereas the lowest results were found in the CTM group. All groups exhibited repairable failures. The finite element analysis showed the lowest stress in root dentin in the UNI system. The CTM system had the largest stress regions at the dentin and dentin-core interface. Conclusions The use of a 2-piece universal glass fiber post system resulted in more fatigue behavior compared with composite resin-custom glass fiber posts.

Quantitative trait locus (QTL) mapping is a useful method for revealing the mechanism of complex genetic traits and identifying new genomic information to accelerate crop improvement. In the present study, 154 F2:3 strains and their parents were used for restriction site-associated DNA sequencing, single-nucleotide polymorphism (SNP) identification, and genetic map construction. After filtering based on stringent filtering standards, 297.5 Gb of clean data were obtained. Further, 5,191 polymorphic SNP markers were identified from each sample, of which 1,997 polymorphic SNP markers were successfully mapped onto 18 different linkage groups. Six QTLs (QPH, QFBW, QDBW, QFW, QFT, and QFC) were identified based on the genetic map using the multiple QTL mapping (MQM) method, which were then assigned to three linkage groups, LG16, LG8, and LG3. QPH, QFBW, QDBW, and QFW were related to fiber yield, while QFT and QFC were related to fiber quality. This is the first study of its kind to map QTL of fiber yield and fiber quality, which will facilitate further understanding of the molecular genetic basis of these traits. However, there are limitations regarding the utilization of this map because several large gaps remain in some linkage groups. Therefore, additional markers need to be developed to further narrow these regions.

Recent advances in nanotechnology have witnessed tremendous progress concerning nanofiber synthesis and practical applications. Electrospinning is a simple, versatile, and cost-effective technology that relies on electrostatic repulsions between surface charges to continuously fabricate various scalable assemblies from a wide range of raw materials (polymers, ceramics, nanoparticles, carbon nanomaterials, gels, etc.) with diameters down to macro-nano scale. Nanofibers prepared by electrospinning possess remarkable large and specific surface area to volume ratio, interconnected and tunable structures, diverse morphologies, physio-chemical and mechanical properties. In this paper, Polyvinylidene fluoride (PVDF) nanofibers with different concentrations and under constant electrospinning conditions have been prepared and characterized. The increase of the PVDF polymeric concentration improved the morphological structure of the PVDF nanofibers due to the enhanced molecular chain entanglement which allows the stretching and elongation of the fibers during the electrospinning process. At higher PVDF concentration, the fiber diameters become thinner and beadless nanofiber mats are obtained. Finally, the potential practical applications of electrospun PVDF nanofibers are addressed in this paper.

This laboratory analysis was done to scrutinize the compressive strength of nominal mix concrete (NMC) and fiber reinforced concrete (FRC) for M30 grade of concrete. In this study, cubes of NMC prepared by adding fly ash 20% and 30% of the weight of cement. Apart from this, the FRC mix prepared by adding steel and glass fiber in the NMC mixture. The experimental study consists of the construction of 84 cubes, out of which 36 cubes of SFRC and 36 cubes of GFRC cast for different percentages of fiber. Out of 36 cubes of SFRC, 18 cubes cast with 20% fly ash and 18 cubes cast with 30% fly ash and the same as for GFRC and 12 cubes of NMC, 6 cubes cast with 20% fly ash and 6 cubes cast with 30% fly ash. The compressive strength calculated by averaging the strength of three cubes cast for each fiber ratio. These mixes tested for its hardened property like compressive strength in this comparative study. The compressive strength tested on UTM after 7 and 28 days curing, where results show improvement in individual fibers.

The study is aimed to utilize the silica fume coated plastic waste in the concrete in place of uncoated plastic waste. The main aim of the study is to evaluate the effect on fresh and mechanical properties of concrete after coating the plastic waste with mineral admixture i.e silica fume. The study of utilization of different kinds of plastics forms in concrete has been carried out earlier as well. The major concern is the bonding between concrete mix and the plastic by which the strength could not be attained as desired as per the grade. The present investigation is an endeavor to enhance the bonding characteristics of waste PET fibers with concrete mix by coating them with mineral admixture such as silica fumes by utilizing epoxy resins as an adhesive. The examination was done by utilizing waste PET fibers in aspect ratio AR 25 (50 mm נ2 mm), AR 50 (100 mm נ2 mm) and AR 75(150 mm/2 mm) and consolidate them as bond weight in separate interims of 3%, 6%, 9% and 12%. The modern and mechanical qualities of concrete mix investigated with incorporation of silica fume coated waste PET fibers and ordinary waste PET fibers were contemplated.

Orange G dye belongs to the class of Azo dye. It is broadly used to dye goods, such as wool and fiber, paper, leather etc. Its undesirable impact on human health involves skin problems like skin irritation, allergy and metamorphosis that leading to cancer. Industrial waste water containing excess of Orange G dye has to be treated to keep the environment safe. Adsorption is an effective way of removing dye from aqueous solution and we have reviewed various adsorbents like like activated-carbon, MnO2nano-particles, saw-dust etc. Various adsorption criteria like temperature, contact time, pH, quantity of adsorbent and dye concentration along-with their size have been reviewed. The kinetics of adsorption and adsorption isotherms together with the thermodynamics of the process have been critically examined.

The fast and high response detection of neurotoxic H2S is of great importance for the environment. In this paper, directly electrospinning technology on the ceramic tube is developed to improve the response of H2S detector based on superlong SnO2 fibers. The submillimeter continuous fibers are deposited directly on ceramic tubes by in-situ electrospinning method and can keep morphology of fibers during calcination. By employing this technology, CuO-doped SnO2 fiber H2S detectors are fabricated, and 10% atom CuO-doped SnO2 H2S detector shows the highest response of 40 toward 1 ​ppm ​H2S at 150 ​°C while the response is only 3.6 for the H2S detector prepared in traditional route. In addition, the in-situ electrospinning H2S detectors show faster response and recovery compared to the H2S detectors fabricated by the conventional way. The high and fast response of H2S detectors based on in-situ electrospinning can be ascribed to the continuous fiber structure and CuO modification. The present in-situ electrospinning technology may provide a new strategy for the development of other gas-detectors and bio-detectors with fast and high response.

GFRP bars reinforced in submerged or moist seawater and ocean concrete is subjected to highly alkaline conditions. While investigating the durability of GFRP bars in alkaline environment, the effect of surrounding temperature and conditioning duration on tensile strength retention (TSR) of GFRP bars is well investigated with laboratory aging of GFRP bars. However, the role of variable bar size and volume fraction of fiber have been poorly investigated. Additionally, various structural codes recommend the use of an additional environmental reduction factor to accurately reflect the long-term performance of GFRP bars in harsh environments. This study presents the development of Random Forest (RF) regression model to predict the TSR of laboratory conditioned bars in alkaline environment based on a reliable database comprising 772 tested specimens. RF model was optimized, trained, and validated using variety of statistical checks available in the literature. The developed RF model was used for the sensitivity and parametric analysis. Moreover, the formulated RF model was used for studying the long-term performance of GFRP rebars in the alkaline concrete environment. The sensitivity analysis exhibited that temperature and pH are among the most influential attributes in TSR, followed by volume fraction of fibers, duration of conditioning, and diameter of the bars, respectively. The bars with larger diameter and high-volume fraction of fibers are less susceptible to degradation in contrast to the small diameter bars and relatively low fiber's volume fraction. Also, the long-term performance revealed that the existing recommendations by various codes regarding environmental reduction factors are conservative and therefore needs revision accordingly.

Drilling muds play an important role in drilling and production operations so that the degree of success in such operations is determined by the proper design of these fluids. To optimize drilling operations and avoid excessive expenditure, it is essential to prepare a drilling mud that is both cheap and efficient. Fluid additives are typically used in drilling systems to improve these fluids' capabilities in terms of hole cleaning capacity, filtration control, viscosity, yield point, heat transfer, etc. However, environmental concerns, cost of production, and availability are always considered challenging factors. This study introduces an eco-friendly herbal fiber in powder and regular forms as a potential alternative to other chemical additives. To do so, Alyssum homolocarpum seed mucilage was added with different concentrations to the water-based drilling muds, and its rheological behavior, filtration control, and the induced formation damage were examined and the optimum concentration was introduced. The results of this study revealed the advantages of the drilling muds formulated with Alyssum in terms of filtration control, rheology, formation damage, and greenness.

In recent years, the development of functional foods targeting gastrointestinal disorders has been in progress. Partially hydrolyzed guar gum (PHGG), which is a water-soluble dietary fiber, is known to have a constipation-improving effect. However, many aspects of the mechanism remain unclear. In this study, we investigated the role of aquaporin-3 (AQP3), which regulates the water content of feces in ameliorative effect of PHGG on constipation. Rats were allowed to freely consume a normal diet or a diet containing 5% PHGG for 14 days, and defecation parameters were measured. We also analyzed the expression levels of genes involved in water transport in the colon. The defecation frequency and volume of rats treated with PHGG were not different from those from the control group, but the fecal water content was significantly increased, and soft stools were observed. The expressions of claudin-1, tight junction protein-1, and cadherin-1, which are involved in tight junctions or adherens junctions, were almost the same in the PHGG-treated group and the control group. The expression level of AQP3 in the colon was significantly decreased in the PHGG-treated group. In this study, PHGG decreased the colonic AQP3 expression, thereby suppressing water transport from the luminal side to the vascular side and improving constipation.

The amalgamation of metallic alloys and fiber-reinforced composites has helped Fiber Metal Laminates (FMLs) like Carbon fiber reinforced aluminum laminates (CARALL) and Glass laminate aluminum reinforced epoxy (GLARE) overcome the limitations of standalone metals and composites. As a result, they have found increasing applications in the aircraft and defense industries. Moreover, the inhomogeneous nature and poor machinability of the materials make hole drilling a challenging task. Therefore, to enhance drilling performance, the paper reports a systematic analysis on the effect of spindle speed and axial feed on key performance measures, including thrust force, machining temperature, surface roughness, hole size, burr size, and chip morphology. Experimental outcomes indicate a significant reduction in the thrust force while utilizing higher spindle speed (4000 rev/min) and lower axial feed (0.1 mm/rev), while the surface finish improved under high feed conditions (0.4 mm/rev). The analysis revealed that machining temperature increased with the employment of higher spindle speed and lower axial feed. Higher spindle speeds and axial feeds are desirable from the perspective of hole accuracy as they help produce holes within H9 diameter tolerance. Burr size was verified to be larger at the hole exit compared to hole entry, with the size of the burr increasing with an increase in spindle speed and axial feed. The results show that the axial feed was the significant variable affecting chip size followed by spindle speed. Higher axial feed (0.4 mm/rev) and spindle speed (4000 rev/min) helped improve the chip breakability, thus helping in better chip evacuation.

Replacing micro-reinforcing fibers with carbon nanotubes (CNTs) is beneficial for improving the impact properties of ultra-high performance concrete (UHPC); however, the weak wettability and dispersibility of CNTs and the weakly bonded interface between CNTs and UHPC limit their effectiveness as composites. Therefore, this study aims to enhance the reinforcement effect of CNTs on the impact properties of UHPC via functionalization. Unlike ordinary CNTs, functionalized CNTs with carboxyl or hydroxyl groups can break the Si–O–Ca–O–Si coordination bond in the C–S–H gel and form a new network in the UHPC matrix, effectively inhibiting the dislocation slip inside UHPC matrix. Furthermore, functionalized CNTs, particularly carboxyl-functionalized CNTs, control the crystallization process and microscopic morphology of the hydration products, significantly decreasing and even eliminating the width of the aggregate–matrix interface transition zone of the UHPC. Moreover, the functionalized CNTs further decrease the attraction of the negatively charged silicate tetrahedron to Ca2+ in the C–S–H gel, while modifying the pore structure (particularly the nanoscale pore structure) of UHPC, leading to the expansion of the intermediate C–S–H layer. The changes in the microstructures of UHPC brought about by the functionalized CNTs significantly enhance its dynamic compressive strength, peak strain, impact toughness, and impact dissipation energy at strain rates of 200–800 s−1. Impact performance of UHPC containing a small amount of carboxyl-functionalized CNTs (especially the short ones) is generally better than that of UHPC containing hydroxyl-functionalized and ordinary CNTs; it is even superior to that of UHPC with a high steel fiber content.

Through an investigation of the microstructure and mechanical properties of extruded Mg–5Bi–xSn (BT5x, x = 0, 2, 4, and 6 wt%) alloys, this study demonstrates that the addition of Sn to an Mg–5Bi binary alloy significantly improves the tensile strength of the extruded alloy. All the extruded alloys exhibit a typical basal fiber texture and a partially dynamically recrystallized (DRXed) microstructure consisting of fine DRXed grains and coarse unDRXed grains. As the Sn content increases from 0 wt% to 6 wt%, the average size of the DRXed grains decreases from 4.2 to 2.8 μm owing to the increase in the amount of precipitates via their grain-boundary pinning effect. The extruded B5 and BT52 alloys contain numerous Mg3Bi2 precipitates, but their size and number density are smaller and higher, respectively, in the latter alloy. Numerous Mg2Sn precipitates as well as Mg3Bi2 precipitates are present in the extruded BT54 and BT56 alloys, and the number density of the Mg2Sn precipitates is higher in the latter alloy because of its higher Sn content. The addition of 2 wt% Sn to the B5 alloy significantly improves the yield strength (YS) and ultimate tensile strength (UTS) of the extruded alloy—by 76 and 57 MPa, respectively. This drastic improvement is the combined outcome of enhanced grain-boundary hardening, precipitation hardening, and solid-solution hardening effects induced by the refined DRXed grains, numerous precipitates, and Sn solute atoms, respectively. The further addition of 2 wt% or 4 wt% Sn to the BT52 alloy leads to moderate increments in the YS and UTS of the extruded alloy. Specifically, each addition of 2 wt% Sn increases the YS and UTS by ~26 and ~20 MPa, respectively, which is attributed mainly to the additional precipitation hardening effect induced by the Mg2Sn precipitates.

Improving the characteristics of local low-strength soils at the construction site is one of the appropriate approaches to employ the soils as a backfill of geogrid-reinforced soil (GRS) walls. In this study, the fiber-cement-treated sand–silt mixture was used as the backfill of walls. The post-earthquake performance of the walls was evaluated by applying the sinusoidal waves on 1 m high reduced-scale physical models and conducting a series of 1g shaking table tests. A comparison of the wall models constructed with treated and untreated backfill indicated the advantages of geogrid-reinforced fiber-cement-treated soil walls subjected to strong ground motion. The results revealed the better behavior of the wall models backfilled with treated soil mixtures under dynamic loading. Such improved performance was more evident in (i) deformation responses, including the lateral displacement of wall facing, deformation mode, failure surfaces, and settlement of backfill surface and (ii) acceleration response in different locations, including facing, reinforced, and retained zones of walls.

High-performance ballistic fibers, such as aramid fiber and ultra-high-molecular-weight polyethylene (UHMWPE), are commonly used in anti-ballistic structures due to their low density, high tensile strength and high specific modulus. However, their low modulus in the thickness direction and insufficient shear strength limits their application in certain ballistic structure. In contrast, carbon fiber reinforced epoxy resin matrix composites (CFRP) have the characteristics of high modulus in the thickness direction and high shear resistance. However, carbon fibers are rarely used and applied for protection purposes. A hybridization with aramid fiber reinforced epoxy resin matrix composites (AFRP) and CFRP has the potential to improve the stiffness and the ballistic property of the typical ballistic fiber composites. The hybrid effects on the flexural property and ballistic performance of the hybrid CFRP/AFRP laminates were investigated. Through conducting mechanical property tests and ballistic tests, two sets of reliable simulation parameters for AFRP and CFRP were established using LS-DYNA software, respectively. The experimental results suggested that by increasing the content of CFRP that the flexural properties of hybrid CFRP/AFRP laminates were enhanced. The ballistic tests’ results and the simulation illustrated that the specific energy absorption by the perforation method of CFRP achieved 77.7% of AFRP. When CFRP was on the striking face, the shear resistance of the laminates and the resistance force to the projectiles was promoted at the initial penetration stage. The proportion of fiber tensile failures in the AFRP layers was also enhanced with the addition of CFRP during the penetration process. These improvements resulted in the ballistic performance of hybrid CFRP/AFRP laminates was better than AFRP when the CFRP content was 20 wt% and 30 wt%.

Purpose To evaluate the association between the intake of specific fibers with prebiotic activity, namely inulin-type fructans (ITFs), fructooligosaccharides (FOSs) and galactooligosaccharides (GOSs), and colorectal cancer risk. Methods Within the PrebiotiCa study, we used data from a multicentric case–control study conducted in Italy and including 1953 incident, histologically confirmed, colorectal cancer patients and 4154 hospital controls. The amount of six prebiotic molecules [ITFs, nystose (FOS), kestose (FOS), 1F-β-fructofuranosylnystose (FOS), raffinose (GOS) and stachyose (GOS)] in a variety of foods was quantified via laboratory analyses. Subjects’ prebiotic fiber intake was estimated by multiplying food frequency questionnaire intake by the prebiotic content of each food item. The odds ratios (OR) of colorectal cancer for quintiles of intakes were derived from logistic regression models including terms for major confounders and total energy intake. Results GOSs intake was inversely associated with colorectal cancer risk. The OR for the highest versus the lowest quintile of intake were 0.73 (95% confidence interval, CI 0.58–0.92) for raffinose and 0.64 (95% CI 0.53–0.77) for stachyose, with significant inverse trends across quintiles. No association was found with total ITFs and FOSs. The association with stachyose was stronger for colon (continuous OR = 0.74, 95% CI 0.66–0.83) than rectal cancer (OR = 0.89, 95% CI 0.79–1.02). Conclusion Colorectal cancer risk was inversely associated with the intake of dietary GOSs, but not ITFs and FOSs.

This paper presents a study about fiber slippage behavior under direct pull-out and assessment of fiber/matrix pull-off bond strength. This study was prepared through theoretical calculations validated by experimental tests. Theoretically, the study shows a general solution for the fiber-slip mechanism in a general matrix using a new frictional-shear-lag model and an analytical model for pull-off bond strength. Experimentally, pull-out tests were conducted for selected types of single fiber in micro-level (glass, carbon, and short-steel fiber); and macro-level (straight steel fiber). The results showed significant improvements in the pull-off bond strength using novel shape of fiber with wide rounded ends-WESF. The pull-off bond strength in normal-weight concrete was found lower than in lightweight concrete, and the matrix with higher compressive strength improves the pull-off bond strength. Also, the steel fiber showed higher pull-off bond strength compared to glass and carbon fiber; whereas the efficiency of short-steel fiber was higher than the long one. All types of fiber showed that the higher aspect ratio reduces the pull-off bond strength. Using the novel-WESF, the performance of fiber-slip improved 52.65% in normal-weight concrete. Moreover, the fiber-slip performance improved 61.79% in sand-lightweight concrete, and 70.20% in all other types of light-weight concrete.

In this study, porous carbon has been prepared through potassium hydroxide (KOH) activation of coconut fiber (CF) and subsequent carbonization in the presence of an inert gas. The activated carbons (AC) were prepared via carbonization of the precursor at different temperatures. Subsequently, their electromagnetic wave absorption (EMWA) performance was investigated at X-band frequency. The phase crystallinity, porous features, and degree of graphitization of the activated carbons were studied using XRD, nitrogen adsorption/desorption isotherm, and Raman spectroscopy, respectively. Using the BET method, the activated carbon prepared at 750 °C displayed a high specific surface area of 602.9 m2 g−1 and an average pore size of 6 nm, which confirms the extant of mesopores. The EMWA was studied using COMSOL Multiphysics software based on the finite element method. Results show that the activated carbon prepared at 750 °C attained an optimal reflection loss of −45.6 dB at 10.96 GHz with a corresponding effective bandwidth of 3.5 GHz at a thickness of 3.0 mm. In conclusion, this study interestingly shows that porous carbon obtained from coconut fiber has great potential for attenuating electromagnetic waves.

Due to the progressive use of landfills and the challenges about their effect on their surrounding environment, the hydraulic and gas permeability of the landfill liners has always been a great concern for geotechnicians. Clay-based materials are usually used as the main material for landfill liners. Various additives are implemented to control the hydraulic and gas permeability of these clay liners under different climate conditions. The attempt of this research was to investigate the effect of using four types of geo-fibers, including ordinary and web polyester, polypropylene, and polyvinyl alcohol fibers, on reducing the hydraulic and gas permeability under wet and dry conditions. In this regard, two sets of water and gas permeability tests were performed for clay–fiber mixtures with 0.2, 0.4, and 0.6 weight percentages of fiber additives. The results showed an initial decrease and then a growth in the permeability coefficients by increasing the fiber dosages, resulting in an optimum percentage for each fiber type. Among the fibers used in this study, polyvinyl alcohol fiber with 0.2 weight per cent performed best by reducing the permeability coefficient by approximately 65% and 75% for hydraulic and gas permeability coefficients under wet and dry conditions.

Poly(arylene sulfide sulfone)/graphene nanoplate (PASS/GNP) composites with segregated structure based on continuous polymer fiber skeletons were fabricated by coating a thin conductive layer on the PASS fibers and then performing compression molding. The formation of a unique segregated conductive network endowed the PASS/GNP composites with high electrical conductivity and excellent electromagnetic interference (EMI) shielding effectiveness (SE), reaching 17.8 ​S/m and 30.1 ​dB, respectively, when the content of the GNPs in the conductive layer was 20 ​wt%. The PASS/GNP composites also exhibited outstanding mechanical properties, which was attributed to the continuous PASS fiber skeletons that could withstand large loads and the strong interfacial interaction between the conductive layers and the PASS fibers that could provide good stress transfer. This approach is suitable for most soluble polymers.

Bu çalışmanın amacı, sonlu elemanlar ve Taguchi yöntemleri kullanılarak tabakalı kompozit plakalarınmodal analizinde fiber tipi ve katman sayısının etkilerini incelemektir. Modal analiz, fiber türleri ve katmansayısı gibi iki kontrol faktörüne sahip L9 ortogonal diziye uygun olarak sonlu elemanlar yazılımı ANSYS ilegerçekleştirilmiştir. Sinyal-Gürültü oranı analizi kullanılarak optimum lif türleri ve katman sayısı belirlenirkenkontrol faktörlerin önem seviyeleri ve yüzde etkileri %95 güven düzeyinde varyans analizi kullanılarakgerçekleştirilmiştir. Bu çalışmadan elde edilen sonuçlara göre, maksimum serbest titreşim değeri üçkatmanlı bor lifi takviyeli tabakalı kompozit plakalar kullanılarak hesaplanmıştır. Bu çalışmadan elde edilensayısal ve istatistiksel sonuçlar, tabakalı kompozit plakalar için uygun fiber tiplerini ve katman sayısınıseçmek için faydalı olabilir., The goal of this study is to examine the effects of fiber type and number of layers on modal analysis oflaminated composite plates using finite element and Taguchi methods. Modal analysis was carried out byfinite element software ANSYS in accordance with L9 orthogonal array which has two control factors suchas fiber types and number of layers. Optimal levels of fiber types and number of layers were determinedusing analysis of Signal-to-Noise ratio, while importance levels and percentage effects of control factorswere performed using analysis of variance at 95% confidence level. According to results obtained from thisstudy, the maximum fundamental natural frequency value was calculated using boron-fiber-reinforcedlaminated composite plates with three layers. Numerical and statistical results obtained from this study canbe useful to select the appropriate fiber types and number of layers for laminated composite plates.

PurposeThe paper aims to provide an investigation about the effect of some selected production parameters such as core yarn type, sheath sliver type and total yarn count factors on core spun vortex yarns' evenness, imperfection and tensile properties. Hence it is aimed to contribute to the literature in vortex spinning where there are limited works related to core-spun vortex spinning.Design/methodology/approachThe paper evaluates the effect of core yarn type, sheath sliver type and total yarn count factors on yarn evenness, imperfections, hairiness and tensile properties. Completely randomised three-factor analysis of variance (ANOVA) was conducted in order to evaluate the effect of core yarn type, sheath sliver type and linear yarn density on core spun vortex yarns' evenness, imperfection and tensile properties at significance level of 0.05. SNK tests were also performed for observing the means of each parameter. Correlation analysis was also conducted to reveal some relationships between yarn evenness and yarn tensile properties.FindingsIn this paper, significant factors related to some production parameters affecting the core-spun vortex yarns' evenness, imperfection, hairiness and tensile properties were found.Originality/valueThere are limited works related to effect of selected production parameters on yarn evenness, Imperfections and Tensile Properties of Hybrid Vortex Yarns.

The analysis of microplastics (MP) becomes more difficult for smaller sizes, especially in complex matrices such as sediment of natural waters. In this work, we analyzed MPs in sediment using laser direct infrared (LDIR) imaging, a relatively new technique in environmental MP studies. Sediment samples were spiked with analytical surrogates (polyethylene spheres), and subjected to density separation, wet peroxide oxidation, calcite removal, and filtration. The extracted particles were coated on to a low-emissivity glass slide which was first examined on a stereomicroscope. Six slides (two sediment samples and four different blanks) were further analyzed using an Agilent LDIR system. Approximately 520 and 430 MP/g were found in the two samples, with diameter ranging 20–3384 μm and 84% being smaller than 100 μm. The increase in particle count with decreasing particle sizes followed a power law curve, suggesting that a large portion of the smaller MPs was generated by the breakdown of larger plastic pieces. Major polymers found in this work included polyamide, polyester, polytetrafluoroethylene, and polyacetal. Most MPs were fragments, while beads and fiber were also found. In the two sediment samples, 14% and 46% of the total particles, respectively, were composed of non-plastic micro-sized particles, including natural polyamide, cellulose, chitin, rubber, and “unknown”. Challenges, potential biases, and uncertainties are discussed. This work is the first application of LDIR imaging on MPs in natural sediment.

Several types of ground improvement methods that employ fiber-reinforcement have been developed in recent years. A series of consolidated drained triaxial compression tests has been conducted here to examine the effect of short fibers on the mechanical properties of Toyoura sand. Sand with 0.0%, 0.2%, 0.4%, and 1% fiber contents, prepared to yield random distribution, was sheared under several confining pressures and controlled via their initial relative densities. The test results showed that the maximum and residual deviator stresses increased, whereas the volumetric expansion decreased with an increase in fiber content. Although the stress ratio η (=q/p’) and specific volume changed depending on the fiber content and confining pressure with shear progression, they each reached the same values for a definite fiber content at the end of shearing, independently of initial relative density. In other words, the unique critical state line can be found for a definite fiber content. Moreover, the greater the fiber content, the larger the slope of the critical state line at the end of shear. Additionally, as the length of fibers shortened with the same percentage of fiber inclusions in sand, the deviator stress and the stress ratio decreased, approaching the shear-strain-volumetric response of unreinforced sand.

This work investigates the scale effect observed on slow crack growth parameters for SiC-based fibers (Nicalon® and Tyranno® ZMI) and how it can be affected by the variability from a batch of tow to another one. A 10% difference on the stress exponents (nt) was numerically estimated using a dedicated Monte Carlo simulation. This effect is however marginal when compared to the lifetime scatter itself. This partly originates from the fiber slack in used tow specimen, assessed by tensile test completing the experimental work. The number of tensile tests to be performed is discussed. Specimen gauge length is an additional and significant source of discrepancies affecting the fiber alignment and subsequently the tow stress exponent.

Microbial metabolism of specific dietary components, such as fiber, contributes to the sophisticated inter-kingdom dialogue in the gut that maintains a stable environment with important beneficial physiological, metabolic, and immunological effects on the host. Historical changes in fiber intake may be contributing to the increase of allergic and hypersensitivity disorders as fiber-derived metabolites are evolutionarily hardwired into the molecular circuitry governing immune cell decision-making processes. In this review, we highlight the importance of fiber as a dietary ingredient, its effects on the microbiome, its effects on immune regulation, the importance of appropriate timing of intervention to target any potential window of opportunity, and potential mechanisms for dietary fibers in the prevention and management of allergic diseases. In addition, we review the human studies examining fiber or prebiotic interventions on asthma and respiratory outcomes, allergic rhinitis, atopic dermatitis, and overall risk of atopic disorders. While exposures, interventions, and outcomes were too heterogeneous for meta-analysis, there is significant potential for using fiber in targeted manipulations of the gut microbiome and its metabolic functions in promoting immune health.

Statement of problem A fiber post is indicated when there is a significant loss of tooth structure and additional support for the restoration is needed. However, whether the use of a glass fiber post affects the fracture susceptibility of the restored anterior teeth is unknown. Purpose The purpose of this systematic review and meta-analysis was to evaluate the fracture resistance of endodontically treated and restored anterior teeth and to answer the research question, “Does the use of a fiber post influence the fracture resistance of endodontically treated and restored anterior teeth compared with alternative restorative treatments?” Material and methods A search was performed in PubMed, Scopus, Web of Science, LILACS, BBO, Cochrane Library, and Embase databases without date and/or language restrictions (updated in July, 2020). In vitro studies comparing the fracture strength of endodontically treated and restored anterior teeth with and without fiber posts were included. The risk of bias was evaluated by using the previous meta-analyses of in vitro studies. The results were presented as standardized mean difference with a 95% confidence interval. Statistical heterogeneity of treatment effects between studies was assessed using the Cochran Q test and the I2 inconsistency test, and values greater than 50% were considered indicative of substantial heterogeneity. Results After the removal of duplicates and title and abstract screening, 31 studies remained. Seventeen were considered low risk of bias, 10 were medium risk of bias, and 4 were high risk of bias. Meta-analysis comparing control and experimental groups favored the use of a fiber post in endodontically treated teeth with some types of restoration to improve fracture resistance (standardized mean difference= 0.5 [0.08; 0.92]); a glass fiber post was also favored (standardized mean difference=0.92 [0.43; 1.42]); for veneer preparations and teeth with cervical cavities, a fiber post increases the fracture strength (standardized mean difference= 0.74 [0.01; 1.47]; 1.18 [0.35; 2.02], respectively). Conclusions The use of glass fiber posts increases the fracture resistance of endodontically treated and restored teeth.

The emerging one-dimensional wire-shaped supercapacitors (SCs) with structural advantages of low mass/volume structural advantages hold great interests in wearable electronic engineering. Although graphene fiber (GF) has full of vigor and tremendous potentiality as promising linear electrode for wire-shaped SCs, simultaneously achieving its facile fabrication process and satisfactory electrochemical performance still remains challenging to date. Herein, two novel types of graphene hybrid fibers, namely ferroferric oxide dots (FODs)@GF and N-doped carbon polyhedrons (NCPs)@GF, have been proposed via a simple and efficient chemical reduction-induced fabrication. Synergistically coupling the electroactive units (FODs and NCPs) with conductive graphene nanosheets endows the fiber-shaped architecture with boosted electrochemical activity, high flexibility and structural integrity. The resultant FODs@GF and NCPs@GF hybrid fibers as linear electrodes both exhibit excellent electrochemical behaviors, including large volumetric specific capacitance, good rate capability, as well as favorable electrochemical kinetics in ionic liquid electrolyte. Based on such two linear electrodes and ionogel electrolyte, a high-performance wire-shaped SC is effectively assembled with ultrahigh volumetric energy density (26.9 mW·h·cm−3), volumetric power density (4900 mW·cm−3) and strong durability over 10000 cycles under straight/bending states. Furthermore, the assembled wire-shaped SC with excellent flexibility and weavability acts as efficient energy storage device for the application in wearable electronics.

Expansion of aquaculture industry is evidently accompanied by an urgent necessity of aquaculture feed production. Traditionally, fish meal (FM) and soybean meal (SBM) have been the primary protein source ingredient in aquaculture diets. However, over exploitation of these commodities has conducted to their unsustainability. Hence, research of unconventional protein alternatives has emerged. Mushroom meal is one of them. To date, mushroom meals have been investigated when supplemented in low levels in aquaculture diets. Furthermore, effects of diets supplemented with mushroom meals have assessed different parameters such as, haematology, immunity, anti–bacterial & anti–oxidant activities, and heat stress. Present study, is aimed to study the effects of graded levels of dietary pink oyster mushroom (Pleurotus djamor) meal (POMM), in growth, feed efficiency, protein utilization, digestive enzymes activities and whole body proximate composition of Nile tilapia (Oreochromis niloticus) fingerlings. Experimental design included a control diet (POMM0) formulated with soybean meal, as main protein source, and four diets designed with increasing levels of POMM: 25%(POMM25); 50%(POMM50); 75%(POMM75); and 100%(POMM100). Experimental diets and final whole body were submitted to a proximate composition analysis. Growth, feed efficiency, protein utilization, and digestive enzyme activities were assessed. Compared to POMM0 and POMM25, weight gain (WG), and specific growth rate (SGR), significantly (P< 0.05) decreased in fish fed POMM50, POMM75 and POMM100%. Feed conversion ratio (FCR), protein efficiency ratio (PER) and survival rate (SR) were not significantly affected by experimental diets. Daily feed intake (DFI), and daily protein intake (DPI), decreased as POMM increased in diets. Compared to POMM0 experimental group, condition factor (K), showed a significantly higher value in fish fed POMM50, and POMM100 experimental diets. Crude fiber of final whole body of POMM100 resulted significantly higher (P< 0.05) compared to that shown in fish fed the rest of experimental diets. Acid and alkaline proteases, trypsin, chymotrypsin, leucine aminopeptidase and amylase of Nile tilapia fingerlings, were not significantly affected by experimental diets. Compared to fish fed POMM0 and POMM25 diets, experimental fish fed POMM50, POMM75, and POMM100 showed a reduction of lipase activity. In conclusion, a POMM level higher than 25% affects growth and lipase activity. While a POMM level higher than 50% affects fiber content in whole body of final fish.

With the aim to obtain enhanced absorbing performance at small thickness and low filling, a robust strategy to fabricate zinc oxide (ZnO) modified carbon fiber (CF) structures have been successfully prepared by using low temperature hydrothermal method. Due to the multi-interface polarization caused by the high specific surface area of the complex heterostructures and the improvement of impedance matching, the composites show excellent electromagnetic wave absorption properties. Under the condition of low filling content (20wt%) and ultra-thin thickness (1.5mm), the excellent absorption performance of minimal reflection loss of −34.4 dB and an effective absorption bandwidth (RL ≤ −10 dB) of 4.94 GHz is achieved. In addition, the effective absorption bandwidth covers the whole 2-18 GHz band with the increase of thickness from 0.5 to 10 mm. This work provides an innovative method for designing the matching layer of carbon-based absorbing materials, and ZnO@CF heterostructure is expected to become a potential absorbing material.

The research on jute fiber reinforced polymer composites is an emergent concern with the development of new materials due to their significant properties like economical, partially biodegradable, and environment friendly. It is wondered that the hydrophilic nature of jute fiber negatively affects the interfacial interaction with hydrophobic polymeric materials in the composite, which then affects the resultant mechanical, microstructural and physico-chemical absorption properties. In order to overcome this fact, researchers have carried out some techniques for fiber surface chemical treatments. On the other hand, due to the low processing costs and design flexibility, thermoplastics deal many benefits over thermoset polymers, and polyethylene shows excellent processing behaviors such as low density, low cost, considerable flex life, outstanding surface hardness, scratch resistance and good electrical insulator. Besides the traditional thermoplastic and thermosetting polymers, montmorillonite nanoclay is also receiving attention to manufacturing fiber polymer nanocomposites for industrial and household applications as well. This review is considered to highlight the progress of jute fiber reinforced polymer nanocomposites. The study also focuses on the several features of jute polymer composites and nanocomposites as a function of fiber chemical treatments.

Fabrication of selective adsorption coatings plays a crucial role in solid-phase microextraction (SPME). Herein, new strategies were developed for the in-situ fabrication of novel cobalt-based carbonaceous coatings on the nickel-titanium alloy (NiTi) fiber substrate using ZIF-67 as a precursor and template through the chemical reaction of ZIF-67 with glucose, dopamine (DA) and melamine, respectively. The adsorption performance of the resulting coatings was evaluated using representative aromatic compounds coupled to high-performance liquid chromatography (HPLC) with ultraviolet detection (HPLC-UV). The results clearly demonstrated that the adsorption selectivity was subject to the surface elemental composition of the fiber coatings. The cobalt and nitrogen co-doped carbonaceous coating showed better adsorption selectivity for ultraviolet filters. In contrast, the cobalt-doped carbonaceous coating exhibited higher adsorption selectivity for polycyclic aromatic hydrocarbons. The fabricated fibers present higher mechanical stability and higher adsorption capability for model analytes than the commercial polydimethylsiloxane and polyacrylate fibers. These new strategies will continue to expand the NiTi fibers as versatile fiber substrates for metal-organic frameworks (MOFs)-derived coating materials with controllable nanostructures and tunable properties.

The results of experiments on ablation of targets made of stainless steel and aluminum by a scanning beam of nanosecond pulses at intensity up to 109 W/cm2 are presented. It was found that the overlap of the impact zones during irradiating leads to an increase in the ablation depth in proportion to the area of overlap of the irradiation spots. This is due to increase in overlap irradiation spots degree, zones with a large number of pulse effects are formed on surface, which increases the depth of the melt bath and leads to the ejection of larger particles. An increase in ablation depth of aluminum increase with increase of the interval between pulses up to 10 ms and overlapping of the irradiation spots. The shape of the ejected particles changes from spherical, when formed from a melt, to an irregular shape, when the target is mechanically destroyed by an internal shock wave. The size and velocity distribution of the ejected particles was determined, and on the basis of these data, the laser radiation shielding coefficients were calculated depending on the degree of overlapping of the irradiation spots. It was found that the main mechanism for the decrease in the efficiency of ablation by a scanning beam of radiation is the backflow of microparticles deposited on the target surface. The analysis of the energy balance of the aluminum ablation process is carried out.

International audience; The output of bio-based polyvinyl alcohol (PVA) has been growing rapidly with a substantial increase of developments both in academic and industrial research areas in the past decade, which is due to its water solubility, plasticity, and degradability. However, PVA is highly flammable with a limiting oxygen index of only 19% owning to its inherent macromolecular structure composed of carbon, hydrogen, and oxygen atoms. The demand for flame retardancy of PVA has been increased rapidly and is generally satisfied by introducing flame retardants via chemical grafting, physical blending, and coating. This review summarizes the flame retardants applied in PVA and their influence on the flammability and mechanical properties of PVA materials. The type of flame retardant additives and their application technologies for various PVA products are presented in terms of various PVA products, such as films, aerogel, fibers, foams, and bulk composites. The films dominate the whole research of flame retardant PVA materials owing to their widespread application. The fire performance and flame retardant mechanism are compared and discussed. Additionally, PVA acted as an assistant agent in some polymeric flame-retardant formulations is also discussed and reviewed.

In this manuscript, we investigate a new technique to describe optical Heisenberg ferromagnetic microscale in Heisenberg group. Based on the computed magnetic optimistic density, we determine optical Heisenberg electromagnetic quasi phi(t(q)), phi(n(q)), phi(b(q))-microscale by using Heisenberg magnetic optimistic phi(t(q)), phi(n(q)), phi(b(q))-density in Heisenberg group. Then, we consider the Heisenberg ferromagnetic model to observe the variation when we compare electromagnetic quasi phi(t(q)), phi(n(q)), phi(b(q)) fields of an electromagnetic flow phase. Moreover, we obtain Heisenberg electric optimistic density of Heisenberg electroosmotic modeling with ferromagnetic design in Heisenberg group. Finally, we illustrate axial optical electroosmotic velocity for rotational field of stator quasi field in Heisenberg group.

OBJETIVES: To assess the effect of various factors on laser fiber tip degradation with the Thulium Fiber Laser (Tm-fiber): fiber stripping, adjustable laser settings (energy, frequency, peak power)...

Interconnected Ni(OH)2 nanoflakes and polyether amine (PEA) were deposited on carbon fiber tows via a facial and effective process of chemical bath deposition and dip coating. Based on this, a win–win benefit of simultaneously improvements in interfacial shear strength (IFSS) of carbon fiber/epoxy composites and the electrochemical activity has been achieved. Compared with CF and CF-Ni(OH)2 composites, the IFSS of CF-Ni(OH)2-PEA/epoxy composite respectively increased 7.9% and 45.4%, which was put down to the covalent bonding of Ni(OH)2-PEA coating with fiber and epoxy matrix, as well as the effective stress transfer by the uniform honeycomb structure of Ni(OH)2. In aqueous KOH electrolyte, the CF-Ni(OH)2-PEA electrode presented the maximum specific capacitance of 689.98F·g−1 at 5 mV·s−1, 572.28F·g−1 at a current density of 0.5 A·g−1 due to the strong adhesion of carbon fiber with Ni(OH)2 by PEA, the reservation of the three-dimensional hollow honeycomb structure of Ni(OH)2 for easy ion-transport and –NH2 functional groups from PEA for providing more active sites. The excellent performance of CF-Ni(OH)2-PEA reinforcement demonstrates its promising potential for application in high performance composites with integrated structure and function, which shows great advantages in various fields of aerospace, energy, electronics, automobile, civil engineering, sports, etc.

Background: In this study, Near-field electrospinning (NFES) technique used with a cylindrical collector to fabricate a large area permanent piezoelectric micro and nanofibers by a prepared solution. NFES requires a small electric field to fabricate fibers. Objective: The objective of this paper to investigate silver nanoparticle (Ag-NP)/ Polyvinylidene fluoride (PVDF) composite as the best piezoelectric material with improved properties to produced tremendously flexible and sensitive piezoelectric material with pertinent conductance. Method: In this paper we used controllable electrospinning technique based on Near-field electrospinning (NFES)The process parameter for Ag-NP/PVDF composite electrospun fiber based on pure PVDF fiber. A PVDF solution concentration of 18 wt.% and 6 wt.% silver nitrate which is relative to the weight of PVDF wt.% with 1058 µS conductivity fibers have been directly written on a rotating cylindrical collector for aligned fiber PVDF/Ag-NP fibers are patterned on fabricated copper (Cu) interdigitated electrodes were implemented on a thin flexible polyethylene terephthalate (PET) substrate and Polydimethylsiloxane (PDMS) used as a package to enhance the durability of the PVDF/ Ag-NP device. Results: A notable effect on the piezoelectric response has been observed after Ag-NP addition confirmed by XRD characterization and tapping test of Ag-NP/PVDF composite fiber. The morphology of the PVDF/Ag-NP fibers and measure diameter by scanning electron microscopy (SEM) and Optical micrograph (OM), of fiber. Finally, The result shows that diameter of PVDF/Ag-NP fibers up to ~7 μm. The. High diffraction peak at 2θ = 20.5˚ was investigated by X-ray diffraction (XRD) in the piezoelectric crystal β-phase structure. While the electromechanical conversion is found enhance from ~0.1 V to ~1 V by the addition of silver nanoparticles (Ag-NPs) in the PVDF solution. Conclusion: In conclusion, we can say that confirmed and validated the addition of Ag-NP in PVDF could enhance the piezoelectric property by using NFES technique with improved crystalline phase content can be useful for a wide range of power and sensing applications like biomedical devices and energy harvesting, among others.

Quaternary nitrogen (N-Q) functionalized porous carbon could be prepared from thermally stabilized polyacrylonitrile (PAN) fiber (PYR) by ZnCl2 activation (PYR-7Z4) and consecutive heat treatment at 950 °C (PYR-7Z4-9.5HT10). The prepared carbonaceous adsorbents could effectively remove nitrate anion from water by 0.6 mmol/g or more in the wide range of equilibrium solution pH (pHe) 3–8. Although the adsorption amounts on the materials derived from PYR were about a half of ion-exchange resin (HP555), fairly good adsorption performance could be realized as carbonaceous materials compared with the other carbon based adsorbents containing nitrogen species. This is caused by the presence of the equivalent N-Q sites on the prepared porous PAN carbon surface. Examining adsorption isotherms of nitrate, PYR-7Z4-9.5HT10 exhibited a little better performance than PYR-7Z4. Comparing adsorption performance of nitrogen-doped rayon based activated carbon fiber (ACF) prepared in our previous study, N-Q sites could be dominantly introduced on carbon surface for the materials derived from PYR. In addition, post heat treatment at 950 °C also seems to be effective to reduce unexpected negatively charged carboxy groups leading to the increase in both adsorption capacity and affinity of nitrate on the carbon surface.

In this work, a modified square photonic crystal fiber (MS-PCF) architecture is exposed with ultra-high negative dispersion for communication window. The validation of the model is successfully performed by applying an efficient full-vector finite element method (FV-FEM) with anisotropic perfectly matched layers (PMLs) for precise simulation of PCFs. Additionally, waveguide dispersion engineering is accomplished by tuning the structural parameters of the MS-PCF. From the numerical investigation, negative dispersion behavior permits remarkable suppression rather than positive dispersion. It offers the high negative dispersion of −2357.54 ps/nm/km and Kerr nonlinearity (γ) of 74.68 W−1 km−1 simultaneously at the operating wavelength, λ = 1550 nm. Nevertheless, the designed fiber ensures the mono mode operation in the entire band of interest from λ = 1340 nm to λ = 1580 nm. MS-PCF with these outstanding optical performances has distinguished potency to be practiced as a dispersion compensating fiber in optical communication systems.

Solid-state fiber dye-sensitized solar cells (SS-FDSSCs) have been the subject of intensive attention and development in recent years. Although this field is only in its infancy, metal-organic frameworks (MOFs) are one such material that has been utilized to further improve the power conversion efficiency of solar cells. In this study, MOF-integrated DSSCs were shown to have potential in the development of solar cell devices with efficiency comparable to or better than that of conventional solar cells. The power conversion efficiency (PCE) of SS-FDSSCs was improved by embedding MOF-801 into a mesoporous-TiO2 (mp-TiO2) layer, which was used as a photoanode in SS-FDSSCs, which are inherently flexible. The PCE of the MOF-integrated SS-FDSSCs was 6.50%, which is comparable to that of the reference devices (4.19%). The MOF-801 enhanced SS-FDSSCs decreased the series resistance (Rs) value, resulting in effective electron extraction with improved short-circuit current density (JSC), while also increasing the shunt resistance (Rsh) value to prevent the recombination of photo-induced electrons. The result is an improved fill factor and, consequently, a higher value for the PCE.

The influences of bulk diffusion and surface exchange on oxygen transport of (La0.6Ca0.4)(Co0.8Fe0.2)O3-δ (LCCF) hollow fiber membranes were investigated. As an outcome, two strategies for increasing the oxygen permeation were pursued. First, porous LCCF hollow fibers as support were coated with a 22 μm dense LCCF separation layer through dip coating and co-sintering. The oxygen permeation of the porous fiber with dense layer reached up to 5.10 mL min−1 cm-2 at 1000 °C in a 50 % CO2 atmosphere. Second, surface etching of dense LCCF hollow fibers with H2SO4 was applied. The surface etching of both inner and outer surfaces leads to a permeation improvement up to 86.0 %. This finding implies that the surface exchange reaction plays a key role in oxygen transport through LCCF hollow fibers. A good long-term (>250 h) stability of the asymmetric hollow fiber in a 50 % CO2 atmosphere was found at 900 °C.

In this study, composite binders were prepared as novel, eco-friendly polymineral binders by using rice husks to produce active silica-containing additive, based on which self-compacting fibre concretes (SCFCs) with high impact strength and impermeability characteristics were created. Two types of fibre were used as disperse reinforcement – namely, steel brass-plated fibre and basalt fibre. Ten different mixes of SCFC were investigated. The rheological characteristics of concrete mixes were determined by a series of tests including slump flow, V-funnel, L-box, U-box and segregation resistance tests. In addition, the impact endurance was determined using standard techniques, such as the impact of hammer blows on both panels and cylinders, and this confirmed the creation of dynamically durable composites with high workability. In addition, the microstructural, morphological and thermal properties of such concrete at 28 days of curing were determined. The results indicated that the incorporation of a composite binder in SCFCs significantly improved the mechanical properties and microstructure of the cement matrix by clogging the capillary pores of the cement paste and reducing the growth of portlandite crystals, thereby increasing the compressive strength of fibre concretes by about 31%, the impact endurance by up to six times, and the crack resistance by up to nine times.

Extrinsic non-autonomic self-healing of composite material is elucidated in two cases of crack, one of them has bridging phenomena which has been created during sample formation and the other has normal crack without bridging. Experiments for mode I composite fracture failure was carried out on a double cantilever beam (DCB) specimen. An open wooden mould technique was used to manufacture the test specimen which was made of unidirectional E-glass fiber and polyester resin. In both cases, healing required some form of manual intervention, with the healing agent being manually catalysed and then injected into the delamination. Before and after healing, an experimental study of the function of fibre bridging was conducted. Before and after the healing process, samples with and without bridging were compared. The average healing efficiency of non-bridging specimens is 101 % , with a maximum healing efficiency of 113.5 % , while the average healing efficiency of bridging specimens is 112.4 % , with a maximum healing efficiency of 132.6 % . The results show the great role of crossing fiber in bridging cases, which increases the efficiency of crack healing, so the transcendence of bridging healing is obvious.

The application of high-fiber ingredients in the swine feed industry has some limitations considering that high amounts of fiber are resistant to endogenous enzymatic degradation in the pig’s gut. However, there is growing interest in fiber fermentation in the intestine of pigs due to their functional properties and potential health benefits. Many strategies have been applied in feed formulations to improve utilization efficiency of fiber-rich ingredients and stimulate their prebiotic effects in pigs. This manuscript reviews chemical compositions, physical properties, and digestibility of fiber-rich diets formulated with fibrous ingredients for growing pigs. Evidences presented in this review indicate there is a great variation in chemical compositions and physical properties of fibrous ingredients, resulting in the discrepancy of energy and fiber digestibility in pig intestine. In practice, fermentation capacity of fiber components in the pig’s intestine can be improved using strategies, such as biological enzymes supplementation and feed processing technologies. Soluble dietary fiber (SDF) and insoluble dietary fiber (IDF), rather than neutral detergent fiber (NDF) and acid detergent fiber (ADF), are recommended in application of pig production to achieve precise feeding. Limitations of current scientific research on determining fiber digestibility and short chain fatty acids (SCFA) production are discussed. Endogenous losses of fiber components from non-dietary materials that result in underestimation of fiber digestibility and SCFA production are discussed in this review. Overall, the purpose of our review is to provide a reference for feeding the pig by choosing the diets formulated with different high-fiber ingredients.

High-velocity impact of foreign objects such as small stones will produce complex damage in composite laminates, which will severely degrade residual strength. This chapter first describes high-velocity impact tests for carbon fiber-reinforced plastic (CFRP) laminates and then observes damage states caused by near-perforation impacts. Extensive delamination and fiber breaks as well as matrix cracks appeared regardless of the stacking sequence. This study also quantitatively evaluates the influence of the stacking sequence and the material system (i.e., the presence or absence of toughened interlayers) on the damage area. Finally, the mechanisms of high-velocity impact damage in CFRP laminates are discussed, based on the observations.

The objective of this study was to determine the influence of height and thickness of the one wall remaining coronal tooth structure on the fracture resistance of an endodontically treated root with resin abutment build-up using resin composite and fiber-reinforced resin composite post. Static and dynamic fracture tests were performed by placing the remaining tooth wall on the tensile side and applying loads at an angle of 30° from the tooth axis. Superior static fracture resistance was observed when the wall remaining on the tooth had a height and thickness greater than 1.0 mm. The dynamic fatigue test showed high loading capacity or fracture resistance in specimens with large height and thickness. The dynamic fatigue test showed the influence of the remaining tooth structure on fracture resistance clearly. In conclusion, the static and dynamic fracture resistances increased with the height and thickness of the one wall remaining tooth structure.