Journal articles: 'Z-fiber'

1

Banakh, T. O. "Fiber Z-sets and fiber rejection homeomorphisms." Mathematical Notes 51, no. 6 (June 1992): 539–42. http://dx.doi.org/10.1007/bf01263294.

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Zhang, Ying, Qian-Jin Zhu, Shuai Gao, Shuang Liu, Long-Hai Li, and Hai-Tao Chen. "Optimization of Technological Parameters of Straw Fiber-Based Plant Fiber Seedling Pot Raw Materials." Applied Sciences 11, no. 15 (August 3, 2021): 7152. http://dx.doi.org/10.3390/app11157152.

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Straw fiber seedling pots are a promising substitute for plastic seedling pots. The mixing mode of straw fiber affects the mechanical properties of the raw material membrane of the seedling pot. To explore the processing technology of making the raw material membrane of the seedling pot with two kinds of plant fibers in a layered manner, the optimal combination of the process parameters of the raw material membrane of the seedling pot without additives in the production process was studied experimentally. Response surface methodology (RSM) was used to analyze the parameters (beating degree of unbleached softwood kraft pulp fiber, beating degree of wheat straw fiber, wheat straw fiber quality percentage content, and film grammage) with regard to the dry tensile index and Z-direction tensile index of the seedling pot body. The optimal process parameter combination with a certain dry tensile index and Z-direction tensile index of seedling pot raw material was obtained by using four factors and five levels of a quadratic regression orthogonal rotation center combination design parameter optimization experiment. The optimal technical parameters were optimized as wheat straw fiber quality percentage content 70%, film grammage 70 g/m2, unbleached softwood kraft pulp fiber beating degree 47–48 °SR, and wheat straw fiber beating degree 65–75 °SR. With the optimal conditions, the dry tensile index of the seedling bowl raw material film was between 21 and 22 N·(m·g−1), and the Z-direction tensile index was greater than 2.1 N·(m·g−1). Using wheat straw fibers and unbleached sulfite wood pulp fibers as raw materials for seedling pots, the raw material membrane of the seedling pots was made in a layered manner. The experimental study proved this feasibility. With this mixing process of raw materials, the straw fiber-based plant fiber seedling pot would meet the demands of a crop nursery after adding chemical additives. The research results provide a theoretical basis and technical support for the manufacture of the raw material membrane of the seedling pot body.

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Nashed, B. S., J. M. Rice, and Yong K. Kim. "Projectile Impact Behavior of Z-Fiber Reinforced Laminar Composites." Advanced Materials Research 441 (January 2012): 717–25. http://dx.doi.org/10.4028/www.scientific.net/amr.441.717.

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The bending toughness, strength retention, resistance to damage and bending stiffness of glass fiber mat, laminar composites under high strain rate impact loading conditions was studied. One of the main disadvantages of laminar composite materials is their poor interlaminar shear strength. Recent work has demonstrated a method of Z-direction reinforcement of these composites using electrostatic flocking techniques improve delamination resistance and fracture toughness without degrading the composites tensile strength or other in-plane properties when loaded quasi-statically. The Z-direction reinforcement is accomplished by electrostatically flocking short fibers perpendicular to and between the composite ply layers. In this study, composite samples were prepared using the flocking method in two fabrication modes by the; so-called Z-Axis wet and Z-Axis dry procedures. In this work, Z-direction reinforced composite panels (including a non reinforced control) that were previously projectile impact damaged were tested using established mechanical testing procedures. Damage areas were quantified and compared using image processing techniques. Three point bending tests were also conducted on these projectile impact damaged panels to determine and compare their bending toughness, strength retention and modulus. The results show that Z-Axis reinforcement by the flocking technique improves the overall mechanical strength and stiffness properties of glass fiber mat laminar composites. For example, Z-Axis reinforced projectile damaged and not damaged glass fiber mat composite laminates are found to have flexural strengths 9% to 15% higher and a flexural modulus (stiffness) 22% to 26% higher than comparable (not Z-Axis flock reinforced) glass fiber mat samples.

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Yao, Yi Yong, Rong Ya Zhou, and Li Ping Zhao. "Research about Jet Flow Mechanism and Flow Field Analysis for Layered Composite Materials." Applied Mechanics and Materials 415 (September 2013): 642–46. http://dx.doi.org/10.4028/www.scientific.net/amm.415.642.

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Layered carbon fiber composite performing microstructure was a part of multi-layer porous piping dielectric structure. At first a jet mechanism was put forward and researched for layered composite materials. The Z reinforcing fibers puncture was put to the layered composite structures. By the CFD simulation analysis, the feasibility of jet puncture was verified, the interlayer strength of the connection was increased and the Z bunch to the carbon fiber was eliminated, which laid theoretical foundation by enhancing the layered carbon fiber composite perform quality.

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Hoffmann, Julian, Alexander Brast, and Gerhard Scharr. "Z-pin insertion process for through-thickness reinforced thermoplastic composites." Journal of Composite Materials 53, no. 2 (June 4, 2018): 173–81. http://dx.doi.org/10.1177/0021998318781233.

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This paper presents a novel method for the ultrasonically assisted insertion of metallic z-pins into thermoplastic composites. Mechanical and microstructural investigations were carried out on glass fiber-reinforced polyamide and polypropylene specimens. The insertion of steel pins into thermoplastic composites led to microstructural changes that differ significantly from the known microstructure of z-pinned thermoset fiber-reinforced plastics. Optical microscopy showed an absence of notable fiber waviness and resin-rich zones around each pin. Instead, the fibers were predominantly deflected in the through-thickness direction by the high insertion forces arising during pin penetration. To gain an initial insight on the resulting properties of the z-pin/thermoplastic interface, the mechanical properties of z-pinned thermoplastic composites under mode I loading were investigated using pullout tests. For reference, the pullout behavior of thermoset carbon fiber-reinforced plastic specimens, reinforced with steel pins was determined too. Due to the poor bonding and lack of friction between the pin and laminate, the determined traction loads of the thermoplastic specimens are well below typical values achieved from pin pullout in thermoset laminates.

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CONSIDINE, JOHN M., DAVID W. VAHEY, ROLAND GLEISNER, ALAN RUDIE, SABINE ROLLAND DU ROSCOAT, and JEAN-FRANCIS BLOCH. "Z-direction fiber orientation in paperboard." October 2010 9, no. 10 (November 1, 2010): 25–32. http://dx.doi.org/10.32964/tj9.10.25.

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This work evaluated the use of conventional tests to show beneficial attributes of z-direction fiber orientation (ZDFO) for structural paperboards. A survey of commercial linerboards indicated the presence of ZDFO in one material that had higher Taber stiffness, out-of-plane shear strength, directional dependence of Scott internal bond strength and directional brightness. Laboratory handsheets were made with a specialized procedure to produce ZDFO. Handsheets with ZDFO had higher out-of-plane shear strength than handsheets formed conventionally. Materials with high out-of-plane shear strength had greater bending stiffness and compressive strength because of their ability to resist shear deformations.

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7

Barrett, David John. "The mechanics of z-fiber reinforcement." Composite Structures 36, no. 1-2 (September 1996): 23–32. http://dx.doi.org/10.1016/s0263-8223(96)00053-0.

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8

Kahle, V. "Fiber optic z-cell for cze." Biomedical Chromatography 13, no. 1 (February 1999): 93–94. http://dx.doi.org/10.1002/(sici)1099-0801(199902)13:1<93::aid-bmc786>3.0.co;2-9.

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9

Gagna, Claude E., W. Clark Lambert, Hon-Reen Kuo, and Patricia N. Farnsworth. "Localization of B-DNA and Z-DNA in Terminally Differentiating Fiber Cells in the Adult Lens." Journal of Histochemistry & Cytochemistry 45, no. 11 (November 1997): 1511–21. http://dx.doi.org/10.1177/002215549704501108.

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We examined histochemically and immunohistochemically the distribution of B- and Z-DNA in the epithelium and terminally differentiating dog lens fiber cells. On the basis of anti-DNA antibody reactivity, qualitative and quantitative data on B- and Z-DNA in cells were determined. Anti-B-DNA immunoreactivity gradually declined throughout nucleated fibers, with a precipitous decrease at ∼90 μm. Anti-Z-DNA antibody binding decreased with a sudden loss of immunoreactivity at ∼90 μm. The pattern of anti-B- and Z-DNA staining correlates with the loss of α-crystallin immunoreactivity, the major lens crystallin, and decreased eosin staining of proteins. Germinative zone cell nuclei showed the highest DNA probe binding values, followed by the superficial fibers, central zone, middle fibers, and deep fibers. The presence of single-stranded (ss)DNA in deeper fibers was detected by anti-ss-DNA antibodies. This is indicative of DNA degradation. These observations suggest that a dramatic reorganization of lens fiber cells' supramolecular order occurs at ∼90 μm, the phase transition zone. (J Histochem Cytochem 45:1511–1521, 1997)

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Threepopnatkul, Poonsub, N. Kaerkitcha, and N. Athipongarporn. "Polycarbonate with Pineapple Leaf Fiber to Produce Functional Composites." Advanced Materials Research 47-50 (June 2008): 674–77. http://dx.doi.org/10.4028/www.scientific.net/amr.47-50.674.

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This research is to study the properties of pineapple leaf fiber reinforced polycarbonate composites (PC/PALF). Surface of pineapple leaf fiber (PALF) was pre-treated with sodium hydroxide (PALF/NaOH) and modified with two different functionalities such as γ-aminopropyl trimethoxy silane (PALF/Z-6011) and γ-methacryloxy propyl trimethoxy silane (PALF/Z-6030). The effects of PALF content and chemical treatment were investigated by Fourier transform infrared spectroscopy, Scanning electron microscopy and mechanical testing. The modified pineapple leaf fibers composite also produces enhanced mechanical properties. Young’s modulus is highest in the case of the PALF/NaOH composites. The PALF/Z-6011 composites showed highest tensile strength and impact strength. In thermal property, the results from Thermogravimetric analysis showed that thermal stability of the composites is lower than that of neat polycarbonate resin and thermal stability decreased with increasing pineapple leaf fiber content.

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11

Wang, Xu Xu, and Li Chen. "Manufacture and Characteristics of Fibrous Composite Z-Pins." Applied Mechanics and Materials 33 (October 2010): 110–13. http://dx.doi.org/10.4028/www.scientific.net/amm.33.110.

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Z-pins are thin fibrous composite or metallic rods that could increase the strength of laminated composites in the thickness direction. In this paper, three kinds of composite z-pins were made by improved pultrusion method. The length of pultrusion die is shortened to 30mm with no function of curing. The curing equipment is individual control drying ovens. And then, tensile properties of z-pins were reported as well as the appearance and fiber content. Results show that three kinds of z-pins have good flexural resilience. The fiber volume fraction is around 60%. Carbon fiber z-pin has smoother surface than aramid fiber z-pin. And, The thinner z-pin corresponds to the higher tensile strength and tensile modulus. The elongation rate of aramid fiber z-pin is greater than that of carbon fiber one.

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12

Thornell, L. E., E. Carlsson, E. Kugelberg, and B. K. Grove. "Myofibrillar M-band structure and composition of physiologically defined rat motor units." American Journal of Physiology-Cell Physiology 253, no. 3 (September 1, 1987): C456—C468. http://dx.doi.org/10.1152/ajpcell.1987.253.3.c456.

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The isometric contraction time of 19 fast and slow rat motor units in the soleus and the anterior tibial muscles were recorded. The motor unit fibers, subsequently distinguished by glycogen depletion, were histochemically differentiated into fiber types and analyzed immunohistochemically for high molecular weight M-band proteins, as well as ultrastructurally for M-band fine structure, Z-disc width, and volume density of mitochondria. All fibers belonging to slow-twitch motor units in both the anterior tibialis and soleus muscles were histochemically classed as type 1. They lacked the Mr 165,000 M-protein, showed ultrastructurally a four-line M-band pattern, and had broad Z-discs, whereas the volume density of the mitochondria varied considerably. Muscle fibers belonging to the fast-twitch motor units were histochemically classed as types 2A and 2B in anterior tibialis and type 2A in soleus. They contained a three- or a five-line M-band pattern and medium-to-thin Z-discs in the anterior tibialis and a five-line M-band pattern and broad Z-discs in the soleus. Furthermore, the volume density of mitochondria showed considerable variation within and in between soleus and anterior tibialis type 2 fibers. As the differences in M-band composition and structure between fiber types overrode the intragroup variability in contraction times of slow and fast units within and between the two muscles, it is concluded that the M-band composition and structure is fundamentally related to whether the fiber is innervated by a slow or fast motor neuron, whereas other parameters such as contraction time, Z-disc width, and mitochondrial content of fibers of fast and slow units are relative and vary between muscles. Thus the M-band appearance can be used as a reliable marker to distinguish between fibers of slow- and fast-twitch motor units in rat leg muscles.

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13

Sathish, Shamachary, John H. Cantrell, and William T. Yost. "Radial variation of elastic properties of SCS-6 silicon carbide fiber." Journal of Materials Research 9, no. 9 (September 1994): 2298–303. http://dx.doi.org/10.1557/jmr.1994.2298.

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The upper and lower bounds of the bulk, shear, and Young's moduli are calculated point-by-point along the radius of SCS-6 silicon carbide fibers using the Hashin-Shtrikman equations from considerations of the Auger spectra along the fiber radius. The calculated values are in agreement with measurements of the average Young modulus obtained over relatively large radial regions of the fiber using scanning acoustic microscopy (SAM). The validity of the Hashin-Shtrikman bounds calculations is enhanced by the agreement found between experimental SAM V(z) curves for fixed z along the fiber radius and the theoretical bounds of such curves obtained from the bounds of the calculated bulk and shear moduli.

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14

Tatarakis, M., R. Aliaga-Rossel, A. E. Dangor, and M. G. Haines. "Optical probing of fiber z-pinch plasmas." Physics of Plasmas 5, no. 3 (March 1998): 682–91. http://dx.doi.org/10.1063/1.872778.

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15

Nordström, Bengt, and Lennart Hermansson. "Effect of softwood kraft fiber coarseness on formation and strength efficiency in twin-wire roll forming." Nordic Pulp & Paper Research Journal 33, no. 2 (July 26, 2018): 237–45. http://dx.doi.org/10.1515/npprj-2018-3029.

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Abstract It has been unclear how fiber coarseness affect formation and the utilization of furnish strength in the machine-made paper (strength efficiency). In this work, the effect of softwood kraft fiber coarseness on formation and strength efficiency in twin-wire roll forming was examined in a pilot machine investigation. A reduction in softwood kraft fiber coarseness from 0.21 to 0.17 mg/m, associated with a reduction in fiber grammage from 6.2 to 5.2 g/m2, was found to have no significant effect on formation at the point of minimum shear during dewatering. The insignificant effect of reduced coarseness can be interpreted as the net result of two effects, namely, an increase in the number of fiber layers at a given grammage (favorable) and an increase in the flocculation tendency (unfavorable). While the effect of coarseness was negligible at the point of minimum shear, coarser fibers enabled larger improvement in formation through the jet-to-wire speed difference. In correspondence to the insignificant effect on formation, fiber coarseness had a negligible effect on tensile strength efficiency and Z-strength at the point of minimum shear. The larger improvement in formation through the jet-to-wire speed difference for the coarser fibers was reflected in a favorable effect on Z-strength efficiency.

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Li, Feng, Ke, Pan, and Nie. "Experimental Study on Shear Performance of Cast-In-Place Ultra-High Performance Concrete Structures." Materials 12, no. 19 (October 5, 2019): 3254. http://dx.doi.org/10.3390/ma12193254.

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In order to study the direct shear properties of ultra-high performance concrete (UHPC) structures, 15 Z-shaped monolithic placement specimens (MPSs) and 12 Z-shaped waterjet treated specimens (WJTSs) were tested to study the shear behavior and failure modes. The effects of steel fiber shape, steel fiber volume fraction and interface treatment on the direct shear properties of UHPC were investigated. The test results demonstrate that the MPSs were reinforced with steel fibers and underwent ductile failure. The ultimate load of the MPS is about 166.9% of the initial cracking load. However, the WJTSs failed in a typical brittle mode. Increasing the fiber volume fraction significantly improves the shear strength, which can reach 24.72 MPa. The steel fiber type has little effect on the shear strength and ductility, while increasing the length of steel fibers improves its ductility and slightly reduces the shear strength. The direct shear strength of the WJTSs made from 16 mm hooked-type steel fibers can reach 9.15 MPa, which is 2.47 times the direct shear strength of the specimens without fibers. Finally, an interaction formula for the shear and compressive strength was proposed on the basis of the experimental results, to predict the shear load-carrying capacity of the cast-in-place UHPC structures.

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Kirmasha, Yasir Khaleel, Mohaiman J. Sharba, Zulkiflle Leman, and Mohamed Thariq Hameed Sultan. "Mechanical Performance of Unstitched and Silk Fiber-Stitched Woven Kenaf Fiber-Reinforced Epoxy Composites." Materials 13, no. 21 (October 28, 2020): 4801. http://dx.doi.org/10.3390/ma13214801.

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Fiber composites are known to have poor through-thickness mechanical properties due to the absence of a Z-direction binder. This issue is more critical with the use of natural fibers due to their low strength compared to synthetic fibers. Stitching is a through-thickness toughening method that is used to introduce fibers in the Z-direction, which will result in better through-thickness mechanical properties. This research was carried out to determine the mechanical properties of unstitched and silk fiber-stitched woven kenaf-reinforced epoxy composites. The woven kenaf mat was stitched with silk fiber using a commercial sewing machine. The specimens were fabricated using a hand lay-up method. Three specimens were fabricated, one unstitched and two silk-stitched with deferent stitching orientations. The results show that the stitched specimens have comparable in-plane mechanical properties to the unstitched specimens. For the tensile mechanical test, stitched specimens show similar and 17.1% higher tensile strength compared to the unstitched specimens. The flexural mechanical test results show around a 9% decrease in the flexural strength for the stitched specimens. On the other hand, the Izod impact mechanical test results show a significant improvement of 33% for the stitched specimens, which means that stitching has successfully improved the out-of-plane mechanical properties. The outcome of this research indicates that the stitched specimens have better mechanical performance compared to the unstitched specimens and that the decrease in the flexural strength is insignificant in contrast with the remarkable enhancement in the impact strength.

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Ma, Ruoke, Xianxian Qin, Zhigao Liu, and Yunlin Fu. "Adsorption Property, Kinetic and Equilibrium Studies of Activated Carbon Fiber Prepared from Liquefied Wood by Zncl2 Activation." Materials 12, no. 9 (April 28, 2019): 1377. http://dx.doi.org/10.3390/ma12091377.

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Activated carbon fiber was prepared from liquefied wood by chemical activation with ZnCl2 (Z-LWACF) at different impregnation ratios, with a particular focus on its adsorption property, kinetic and isotherm. The characterization and properties of Z-LWACFs were investigated by nitrogen adsorption/desorption, X-ray photoelectron spectroscopy (XPS), methylene blue (MB) and iodine adsorption. Two activation process methods were employed to prepare Z-LWACF and contrasted with others fibers. The results showed that the Z-LWACF obtained by one-step ZnCl2 activation present higher yields and specific surface area than others fibers. Besides, the change of MB adsorption value at different impregnation ratios was consistent with pore structure distribution above 1.5 nm pore size, indicating that larger micropores (1.5 to 2 nm) and mesopores played a major role in the MB adsorption by Z-LWACF. The kinetics of MB adsorption process was found to follow the pseudo-second-order kinetic model and the adsorption rate was controlled by chemisorption. It was also found that MB adsroption by Z-LWACF belonged to monolayer adsorption and Z-LWACF was easy to adsorb MB.

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Sengur-Tasdemir, Reyhan, Burcu Sayinli, Gulsum Melike Urper, Havva Esra Tutuncu, Nevin Gul-Karaguler, Esra Ates-Genceli, Volodymyr V. Tarabara, and Ismail Koyuncu. "Hollow fiber nanofiltration membranes with integrated aquaporin Z." New Journal of Chemistry 42, no. 21 (2018): 17769–78. http://dx.doi.org/10.1039/c8nj04367a.

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Riley, R., D. Scudder, J. Shlachter, and R. Lovberg. "Instability heating of a solid fiber Z‐pinch." Physics of Plasmas 3, no. 4 (April 1996): 1314–23. http://dx.doi.org/10.1063/1.871785.

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Tan, Soo Jin, A. G. Supri, and Pei Leng Teh. "Effect of PE-g-MAH as Compatibilizer on Properties of LDPE/NR/WHF Composites." Applied Mechanics and Materials 284-287 (January 2013): 87–93. http://dx.doi.org/10.4028/www.scientific.net/amm.284-287.87.

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In this work, the effect of PE-g-MAH as compatibilizer in polyethylene/ natural rubber/ water hyacinth fibers composites were prepared and characterized in terms of tensile properties, morphology properties, swelling behavior and FTIR characteristic. Water hyacinth fibers (WHF) was used as reinforced fiber in the composites incorporated into the LDPE/NR matrices with different fiber loading. LDPE/NR/WHF composites were prepared with Z-blade mixer at 180°C with rotor speed of 50 rpm for 10 minutes. The presence of PE-g-MAH increased the tensile strength and Young’s modulus while reduced the elongation at break of LDPE/NR/WHF composites. The molar sorption of the composites decreased as the fiber loading increased. SEM morphology showed a better fiber dispersion and fiber distribution indicated PE-g-MAH improved the interfaces between water hyacinth fiber and LDPE/NR matrices. The absorption peak at 1741.52cm-1indicated ester carbonyl group in LDPE/NR/WHFPE-g-MAHcomposites.

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Guo, Mingrui, Fengxin Sun, Lei Wang, Yuan Xue, Ruihua Yang, and Weidong Gao. "Analysis of the appearance of two-color cotton yarn by the double-channel spinning system." Textile Research Journal 89, no. 9 (May 29, 2018): 1712–24. http://dx.doi.org/10.1177/0040517518779250.

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The main aim of this paper is to investigate the fiber distribution on the surface of a kind of novel two-color yarn spun by regulating the feeding ratio of two colored rovings on a modified ring spinning frame, which is named the double-channel spinning frame. The surface distribution ratio ( SDR) and the coefficient of variation of surface distribution evenness ( CV sd) of the two colored fiber strands in the yarns was used to quantify the fiber distribution feature along the yarns based on a purpose-made image acquisition device and the corresponding image processing method. The effect of the weight ratio, roving feeding position and spinning method on the mean SDR and CV sd were studied, and the testing results of the Z-twist and S-twist two-color yarns spun by a modified traditional ring spinning frame as well as the yarns spun by a modified compact spinning frame were compared with each other. The fibers of the left-hand roving are more likely to distribute in the surface of Z-twist yarn, while the fibers of the right-hand roving tend to distribute in the surface of S-twist yarn. Four linear fitting equations of the 19.4 tex Z-twist and S-twist two-color ring spun yarns and two-color compact spun yarns were developed to predict the relationships between the mean SDR and weight ratio of two colored fibers.

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Ghosh, Ranajay, and Suvranu De. "Z-fiber influence on high speed penetration of 3D orthogonal woven fiber composites." Mechanics of Materials 68 (January 2014): 147–63. http://dx.doi.org/10.1016/j.mechmat.2013.06.008.

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Straub, V., R. E. Bittner, J. J. Léger, and T. Voit. "Direct visualization of the dystrophin network on skeletal muscle fiber membrane." Journal of Cell Biology 119, no. 5 (December 1, 1992): 1183–91. http://dx.doi.org/10.1083/jcb.119.5.1183.

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Dystrophin, the protein product of the Duchenne muscular dystrophy (DMD) gene locus, is expressed on the muscle fiber surface. One key to further understanding of the cellular function of dystrophin would be extended knowledge about its subcellular organization. We have shown that dystrophin molecules are not uniformly distributed over the humen, rat, and mouse skeletal muscle fiber surface using three independent methods. Incubation of single-teased muscle fibers with antibodies to dystrophin revealed a network of denser transversal rings (costameres) and finer longitudinal interconnections. Double staining of longitudinal semithin cryosections for dystrophin and alpha-actinin showed spatial juxtaposition of the costameres to the Z bands. Where peripheral myonuclei precluded direct contact of dystrophin to the Z bands the organization of dystrophin was altered into lacunae harboring the myonucleus. These lacunae were surrounded by a dystrophin ring and covered by a more uniform dystrophin veil. Mechanical skinning of single-teased fibers revealed tighter mechanical connection of dystrophin to the plasma membrane than to the underlying internal domain of the muscle fiber. The entire dystrophin network remained preserved in its structure on isolated muscle sarcolemma and identical in appearance to the pattern observed on teased fibers. Therefore, connection of defined areas of plasma membrane or its constituents such as ion channels to single sarcomeres might be a potential function exerted by dystrophin alone or in conjunction with other submembrane cytoskeletal proteins.

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Kindler, Joseph, Phil Khoury, Elaine Urbina, and Babette Zemel. "Dietary Fiber and Bone Density in Youth with Type 2 Diabetes." Current Developments in Nutrition 4, Supplement_2 (May 29, 2020): 1649. http://dx.doi.org/10.1093/cdn/nzaa063_047.

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Abstract Objectives Assess relationships between dietary fiber and bone density in youth with type 2 diabetes, obesity, and healthy weight. Methods Cross-sectional study of youth (56% African American, 67% female) ages 10–23 years with type 2 diabetes (n = 180), obesity (BMI >95th; n = 226), or healthy weight (BMI < 85th; n = 238). Total body bone mineral density (BMD) was assessed via DXA. BMD standard deviation scores (“Z-scores”) were computed using published reference data. Dietary fiber (total, soluble, and insoluble) and total calories were assessed via 3-day food diaries, which were analyzed using the Nutrition Data System for Research. Relationships between dietary fiber and BMD Z-score were assessed using linear regression. Separate analyses were performed for total, soluble, and insoluble fiber, and each regression model included age, sex, ancestry, total calories, group, and fiber (total, soluble, or insoluble), as well as group by fiber interactions. Results BMD Z-score was greater in the type 2 diabetes and obese compared to the healthy weight group (P < 0.001). Total, soluble, and insoluble fiber intakes were significantly greater in the healthy weight versus obese group (all P < 0.05), but only marginally greater than the type 2 diabetes group (all P = 0.06–0.10). Regression analyses demonstrated positive relationships between total, soluble, and insoluble fiber intakes and BMD Z-score (all P < 0.05). However, significant group by fiber interactions indicated that the positive relationships between dietary fiber intakes and BMD Z-score was evident only in the healthy weight group (all P < 0.005). Similar relationships were observed when considering BMD Z-score adjusted for height Z-score. Conclusions Prior studies have reported a favorable influence of dietary fiber on bone mineral accrual in healthy individuals and metabolic health in adults with insulin resistance. Dietary strategies promoting increased fiber consumption warrant investigation with respect to fracture prevention and glycemic control in youth with type 2 diabetes. Funding Sources NIH-NHLBI, American Diabetes Association, and Endocrine Fellows Foundation.

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Riley, D. A., S. Ellis, and J. L. Bain. "Catalase-positive microperoxisomes in rat soleus and extensor digitorum longus muscle fiber types." Journal of Histochemistry & Cytochemistry 36, no. 6 (June 1988): 633–37. http://dx.doi.org/10.1177/36.6.3367048.

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The size, distribution, and content of catalase-reactive microperoxisomes were studied cytochemically in slow-twitch oxidative (SO), fast-twitch oxidative glycolytic (FOG), and fast-twitch glycolytic (FG) fibers of soleus and extensor digitorum longus (EDL) rat muscles. Fiber types were classified on the basis of mitochondrial content and distribution, Z-band widths, and myofibril size and shape. Microperoxisomes were generally located between myofibrils at the I-bands. The absence of crystalloid inclusions prevented positive identification of microperoxisomes in nonreacted and aminotriazole-inhibited muscles. EDL and soleus SO fibers possessed the largest microperoxisomes, whereas FOG and FG fibers of the EDL contained small- to medium-sized microperoxisomes. Comparing either microperoxisome number per muscle fiber area or microperoxisome area per fiber area revealed significant differences between fiber types with this ranking: soleus SO greater than EDL SO greater than EDL FOG greater than EDL FG. The present observations demonstrate that the content of catalase-positive microperoxisomes is greatest in the oxidative muscle fiber types. These cytochemical findings account for the higher catalase activity in homogenates of soleus muscles as compared to that of EDL muscles, because the soleus contains more oxidative fibers than EDL.

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Bellinger, Phillip, Ben Desbrow, Wim Derave, Eline Lievens, Chris Irwin, Surendran Sabapathy, Ben Kennedy, et al. "Muscle fiber typology is associated with the incidence of overreaching in response to overload training." Journal of Applied Physiology 129, no. 4 (October 1, 2020): 823–36. http://dx.doi.org/10.1152/japplphysiol.00314.2020.

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Variability in the performance responses following an overload training period and subsequent taper was associated with the variation in the muscle fiber typology of the gastrocnemius. Runners with an estimated higher proportion of type I fibers (i.e., lower carnosine z-score) were able to maintain performance in response to an overload training period and subsequently achieve a superior performance supercompensation. These findings show that muscle fiber typology contributes to the variability in performance responses following training.

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Ying, Zhiping, Xudong Hu, Xiaoying Cheng, and Zhenyu Wu. "Numerical investigation on the effect of tow tension on the geometry of three-dimensional orthogonally woven fabric." Textile Research Journal 89, no. 18 (December 30, 2018): 3779–91. http://dx.doi.org/10.1177/0040517518821912.

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The fabric geometry determines the mechanical performance of a textile composite. This paper investigates the effect of tow tension on the fabric geometry during the weaving process. A numerical model at the fiber scale was established by representing the fiber as a chain of truss elements connected by fully flexible hinges and having strong tensile modules. Fabric samples were woven on a homemade loom under different tension configurations to verify the numerical model. The model results with respect to the tow cross-section and path are in good agreement with observations of the homemade fabric sample. The tow cross-section deformation is the consequence of fiber rearrangement due to the transverse force originating from Z-binder tension. It is also found that the crimps of weft tows are different to those of warp tows. For weft tows, appreciable crimping is found in the regions of intercrossing with the Z-binder tow. Meanwhile, fibers undulate at the edges and remain straight in the middle of warp tows.

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Liu, Wei, Gui Qiong Jiao, Jing Guo, and Hao Tian Jiang. "A Pre-Stitching Method to Manufacture Z-Pins Reinforced Woven Ceramic Matrix Composite Laminates." Advanced Materials Research 721 (July 2013): 117–20. http://dx.doi.org/10.4028/www.scientific.net/amr.721.117.

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Z-pins reinforced 2D ceramic matrix composites (CMCs), integratedly designed new materials, are developed to enhance 2D CMCs through-thickness in the form of Z-pins and to ensure significant increase in interlaminar fracture toughness, delamination resistance and impact resistance, and Z-pins reinforced 2D CMCs have much application. A manual pre-stitching method is developed to make holes in the graphite fixture to control Z-pins row spacings and to introduce yarns of 3000 T300 carbon fibers bundle into a preform. Z-pins reinforced woven CMCs for research were manufactured successfully by repeatedly using chemical vapor infiltration (CVI) to infiltrate SiC matrix into woven preform and carbon fiber sutures. It is shown that this method of manufactured Z-pins reinforced woven CMC is feasible.

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Klein, John R., and John Rognes. "The fiber of the linearization map A(∗) → K(Z)." Topology 36, no. 4 (July 1997): 829–48. http://dx.doi.org/10.1016/s0040-9383(96)00040-7.

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Klir, D., P. Kubes, and J. Kravarik. "Imploding$Z$-Pinch Plasmas Formed From a Carbon Fiber." IEEE Transactions on Plasma Science 34, no. 5 (October 2006): 2303–11. http://dx.doi.org/10.1109/tps.2006.878614.

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32

Scruggs, Alexander M., Sebastian Kirmse, and Kuang-Ting Hsiao. "Enhancement of Through-Thickness Thermal Transport in Unidirectional Carbon Fiber Reinforced Plastic Laminates due to the Synergetic Role of Carbon Nanofiber Z-Threads." Journal of Nanomaterials 2019 (January 3, 2019): 1–13. http://dx.doi.org/10.1155/2019/8928917.

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This study experimentally and analytically examined the influence of carbon nanofiber (CNF) z-threads on the through-thickness (i.e., z-direction) thermal conductivity of unidirectional carbon fiber reinforced plastics (CFRPs). It was hypothesized that a network of CNF z-threads within CFRPs would provide a thermally conductive microstructure throughout the sample thickness that would increase the through-thickness thermal conductivity. The experiments showed that the through-thickness thermal conductivity of the CNF z-threaded CFRPs (9.85 W/m-K) was approximately 7.53 times greater than that of the control CFRPs (1.31 W/m-K) and 2.73 times greater than that of the unaligned CNF-modified CFRPs (3.61 W/m-K). Accordingly, the CNF z-threads were found to play a substantial role in increasing the through-thickness thermal conductivity of CFRPs. To better understand the role of the CNF z-threads in through-thickness thermal transport, simple logical models of the CFRPs were constructed and then compared with the experimental results. Through these analyses, it was determined that CNF z-threads substantially enhance the through-thickness thermal conductivity by creating carbon fiber-CNF linkages throughout the CFRP laminate; these linkages allow the heat flow to largely bypass the resistive resin that envelops the carbon fibers. In addition, thermal infrared tests illustrated that the increased through-thickness thermal conductivity of the CNF z-threaded CFRP enabled the location and visualization of defects within the laminate, which was not possible with the control CFRP.

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33

Riley, Danny A., James L. W. Bain, Joyce L. Thompson, Robert H. Fitts, Jeffrey J. Widrick, Scott W. Trappe, Todd A. Trappe, and David L. Costill. "Thin filament diversity and physiological properties of fast and slow fiber types in astronaut leg muscles." Journal of Applied Physiology 92, no. 2 (February 1, 2002): 817–25. http://dx.doi.org/10.1152/japplphysiol.00717.2001.

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Slow type I fibers in soleus and fast white (IIa/IIx, IIx), fast red (IIa), and slow red (I) fibers in gastrocnemius were examined electron microscopically and physiologically from pre- and postflight biopsies of four astronauts from the 17-day, Life and Microgravity Sciences Spacelab Shuttle Transport System-78 mission. At 2.5-μm sarcomere length, thick filament density is ∼1,012 filaments/μm2 in all fiber types and unchanged by spaceflight. In preflight aldehyde-fixed biopsies, gastrocnemius fibers possess higher percentages (∼23%) of short thin filaments than soleus (9%). In type I fibers, spaceflight increases short, thin filament content from 9 to 24% in soleus and from 26 to 31% in gastrocnemius. Thick and thin filament spacing is wider at short sarcomere lengths. The Z-band lattice is also expanded, except for soleus type I fibers with presumably stiffer Z bands. Thin filament packing density correlates directly with specific tension for gastrocnemius fibers but not soleus. Thin filament density is inversely related to shortening velocity in all fibers. Thin filament structural variation contributes to the functional diversity of normal and spaceflight-unloaded muscles.

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Tausif, Muhammad, Brian Duffy, Sergei Grishanov, Hamish Carr, and Stephen J. Russell. "Three-Dimensional Fiber Segment Orientation Distribution Using X-Ray Microtomography." Microscopy and Microanalysis 20, no. 4 (May 1, 2014): 1294–303. http://dx.doi.org/10.1017/s1431927614000695.

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AbstractThe orientation of fibers in assemblies such as nonwovens has a major influence on the anisotropy of properties of the bulk structure and is strongly influenced by the processes used to manufacture the fabric. To build a detailed understanding of a fabric’s geometry and architecture it is important that fiber orientation in three dimensions is evaluated since out-of-plane orientations may also contribute to the physical properties of the fabric. In this study, a technique for measuring fiber segment orientation as proposed by Eberhardt and Clarke is implemented and experimentally studied based on analysis of X-ray computed microtomographic data. Fiber segment orientation distributions were extracted from volumetric X-ray microtomography data sets of hydroentangled nonwoven fabrics manufactured from parallel-laid, cross-laid, and air-laid webs. Spherical coordinates represented the orientation of individual fibers. Physical testing of the samples by means of zero-span tensile testing and z-directional tensile testing was employed to compare with the computed results.

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35

Shi, Huyan, Lixin Xue, Ailin Gao, and Qingbo Zhou. "Dual layer hollow fiber PVDF ultra-filtration membranes containing Ag nano-particle loaded zeolite with longer term anti-bacterial capacity in salt water." Water Science and Technology 73, no. 9 (February 5, 2016): 2159–67. http://dx.doi.org/10.2166/wst.2016.062.

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Dual layer polyvinylidene fluoride (PVDF), antibacterial, hollow fiber, ultra-filtration composite membranes with antibacterial particles (silver (Ag) nano-particles loaded zeolite (Z-Ag)) in the outer layer were prepared with high water flux and desired pore sizes. The amounts of Ag+ released from the composite membranes, freshly made and stored in water and salt solution, were measured. The result indicated that dual layer PVDF antibacterial hollow fiber containing Z-Ag (M-1-Ag) still possessed the ability of continuous release of Ag+ even after exposure to water with high ionic content, showing a longer term resistance to bacterial adhesion and antibacterial activity than membrane doped with Z-Ag+ (M-1). Results from an anti-adhesion and bacteria killing test with Escherichia coli supported that the antibacterial efficiency of dual hollow fiber PVDF membranes with Z-Ag was much higher than those with Z-Ag+ after long time storage in water or exposure to phosphate buffered saline (PBS) solution. This novel hollow fiber membrane may find applications in constructing sea water pretreatment devices with long term antifouling capability for the desalination processes.

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36

Fu, Jianan, Chunying Guan, Zheng Zhu, Meng Wang, Peng Huang, Ping Li, Jinhui Shi, and Libo Yuan. "In-Fiber M-Z Interferometer Based on Cascaded Long Period Gratings in Embedded-Core Fiber." IEEE Photonics Technology Letters 29, no. 21 (November 1, 2017): 1876–79. http://dx.doi.org/10.1109/lpt.2017.2754503.

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37

Villalón, Mario, Hugo Vega, Nahary Montoya, Byron Rubio, Julio Hernandez, Omar Mendoza, Roberto Salas-Zuñiga, et al. "Comparative Study on the Effect that Coir Fibers Have on the Dynamic or Quasi-Static Elastic Moduli of Glass Fiber Laminates Obtained by the Vacuum Bag Technique." Key Engineering Materials 668 (October 2015): 137–44. http://dx.doi.org/10.4028/www.scientific.net/kem.668.137.

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The use of natural fibers has a great interest due to their damping properties, low density and moderate strength. The effect of incorporating chopped natural fibers, as disperse reinforced phase, on the dynamic or quasi-static elastic modulus of glass fiber laminates is presented. Squares of 32 cm2 plain wave glass fiber prepreg with epoxy resin were used in a stacking sequence [0]4. Short length chopped (1-3 mm) natural coir fiber was placed in between of each glass fiber prepreg sheet (4) and laminates were prepared by the vacuum bag technique. The volume fraction of natural fiber was 30% (mass fraction of 10%) and samples of 254 mm length and 25.4 mm width were cut and tested at vibration conditions in a cantilever beam arrangement. The vibration frequency was measured by an accelerometer ADXL335 at z-axis, perpendicular to the sample test plane and the elastic modulus was estimated with the cantilever model. The results showed that the samples with coir fiber showed an increase in the dynamic elastic modulus value of 150 to 171% with regard to that one of glass fiber samples without fiber. Standard Test Method for Tensile Properties of Polymer Matrix Composite Materials (ASTM D3039) was also used to further characterize the thin samples (≈0.75 mm) with an Instron machine 8800, 25kN. The tensile properties obtained are lower for coir fiber samples than the ones without.

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38

Cheng, Xiaoying, Hongshui Zhou, Zhenyu Wu, and Xudong Hu. "An investigation into self-sensing property of hat-shaped 3D orthogonal woven composite under bending test." Journal of Reinforced Plastics and Composites 38, no. 4 (October 25, 2018): 149–66. http://dx.doi.org/10.1177/0731684418808093.

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In this paper, the influence of damage and deformation on the electrical property of carbon fibers in the hat-shaped 3D orthogonal woven fabric-reinforced composite structure is studied. A method of producing parallel sensor arrays was proposed, in which the warp yarns made of carbon fibers were separated by isolated Kevlar fibers as weft yarns and Z-yarns. The sensor array unitized the self-sensing property of carbon fiber and could detect the damage and deformation distribution along the transverse direction of the composite under bending tests. Both the experiments and simulations had been conducted to analyze the mechanical and electrical responses of the carbon fiber array. By comparing the experimental results and simulation data, the method was validated and the influences of damage and deformation distribution on the resistance variation of carbon fibers were revealed.

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39

Wang, Sian, Yunhe Zhang, Pibo Sun, Yanhong Cui, and Gaohui Wu. "Microstructure and Flexural Properties of Z-Pinned Carbon Fiber-Reinforced Aluminum Matrix Composites." Materials 12, no. 1 (January 7, 2019): 174. http://dx.doi.org/10.3390/ma12010174.

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Z-pinning can significantly improve the interlaminar shear properties of carbon fiber-reinforced aluminum matrix composites (Cf/Al). However, the effect of the metal z-pin on the in-plane properties of Cf/Al is unclear. This study examines the effect of the z-pin on the flexural strength and failure mechanism of Cf/Al composites with different volume contents and diameters of the z-pins. The introduction of a z-pin leads to the formation of a brittle phase at the z-pin/matrix interface and microstructural damage such as aluminum-rich pockets and carbon fiber waviness, thereby resulting in a reduction of the flexural strength. The three-point flexural test results show that the adding of a metal z-pin results in reducing the Cf/Al composites’ flexural strength by 2–25%. SEM imaging of the fracture surfaces revealed that a higher degree of interfacial reaction led to more cracks on the surface of the z-pin. This crack-susceptible interface layer between the z-pin and the matrix is likely the primary cause of the reduction of the flexural strength.

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40

Purnomo, P., Putu Setyarini, and Agus Anggono. "Fiber orientation effect on fracture toughness of silk fiber-reinforced zeolite/HDPE composites." FME Transactions 49, no. 1 (2021): 128–34. http://dx.doi.org/10.5937/fme2101128p.

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The aim of this work is to investigate the fracture toughness and deformation of silk fiber (SF)-reinforced zeolite (Z)/high density polyathylene (HDPE) composites. The chopped SFs are arranged in the thickness middle of the dry mixture of Z/HDPE powder that has been prepared in a mold. Composites were produced by the compression molding to produce double-edge notch tensile (DENT). The fracture toughness characterization was carried out based on essential work of fracture method. The results show that the presence of SF increased the essential fracture work even though the non-essential fracture work for Z/HDPE was higher than S-Z/HDPE. The evolution of plastic zone growth coincides with the growth of the fracture process zone (FPZ) whose height has no effect on energy consumption.

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41

Bilisik, Kadir. "Multiaxis three-dimensional weaving for composites: A review." Textile Research Journal 82, no. 7 (February 1, 2012): 725–43. http://dx.doi.org/10.1177/0040517511435013.

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The aim of this study is to review three-dimensional (3D) fabrics and a critical review is especially provided on the development of multiaxis 3D woven preform structures and techniques. 3D preforms are classified based on various parameters depending on the fiber sets, fiber orientation and interlacements, and micro–meso unit cells and macro geometry. Biaxial and triaxial two-dimensional (2D) fabrics have been widely used as structural composite parts in various technical areas. However, they suffer delamination between their layers due to the lack of fibers. 3D woven fabrics have multiple layers and no delamination due to the presence of Z-fibers. However, the 3D woven fabrics have low in-plane properties. Multiaxis 3D knitted fabrics have no delamination and their in-plane properties are enhanced due to the ±bias yarn layers. However, they have limitations regarding multiple layering and layer sequences. Multiaxis 3D woven fabrics have multiple layers and no delamination due to Z-fibers and in-plane properties enhanced due to the ±bias yarn layers. Also, the layer sequence can be arranged based on end-use requirements. However, the multiaxis 3D weaving technique is at an early stage of development and needs to be fully automated. This will be a future technological challenge in the area of multiaxis 3D weaving.

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42

Chittenden, J. P., and M. G. Haines. "Processes terminating radiative collapse in a hydrogen fiber Z pinch." Physics of Fluids B: Plasma Physics 2, no. 8 (August 1990): 1889–97. http://dx.doi.org/10.1063/1.859460.

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43

Aliaga-Rossel, R., S. V. Lebedev, J. P. Chittenden, I. H. Mitchell, R. Saavedra, A. E. Dangor, and M. G. Haines. "Optical measurements of plasma dynamics in carbon fiber Z-pinches." IEEE Transactions on Plasma Science 26, no. 4 (1998): 1101–7. http://dx.doi.org/10.1109/27.725138.

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44

Klir, D., P. Kubes, and J. Kravarik. "Carbon fiber Z-pinch driven by microsecond-long capacitive discharge." Czechoslovak Journal of Physics 54, S3 (March 2004): C264—C273. http://dx.doi.org/10.1007/bf03166411.

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45

Li, Fan, Ma, Xue, Yuan, Dang, and Meng. "Influence of Reinforcement Structures and Hybrid Types on Inter-Laminar Shear Performance of Carbon-Glass Hybrid Fibers/Bismaleimide Composites Under Long-Term Thermo-Oxidative Aging." Polymers 11, no. 8 (August 1, 2019): 1288. http://dx.doi.org/10.3390/polym11081288.

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The effects of reinforcement structures and hybrid types on the inter-laminar shear strength (ILSS) of carbon-glass hybrid fibers/bismaleimide composites under thermo-oxidative aging conditions were investigated. The process resulted in progressive deterioration of the matrix and fiber/matrix interfaces, in the form of chain scissions, weight loss, and fiber/matrix debonding, which significantly led to the decrease of the ILSS of composites. Moreover, the three-dimensional orthogonal woven hybrid composites (3D composites) showed higher ILSS retention rate than those of the laminated orthogonal hybrid composites (laminated composites). No delamination occurred in the aged 3D composites like in the aged laminated composites. This was because the Z-binder yarns in the 3D composites resisted the inter-laminar shear load, although the resin was damaged and the adhesive force between fiber bundles and resin decreased seriously after thermo-oxidative aging. Meanwhile, the ILSS retention rate of the laminated composites with the carbon fiber as intermediate layers was higher than that of the laminated composites with the glass fiber as the intermediate layers. This was because the carbon fiber/bismaleimide interface bonding performance was stronger than that of the glass fiber/bismaleimide at the same thermo-oxidative aging condition.

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46

Vincent, Barbara, Katrien De Bock, Monique Ramaekers, Els Van den Eede, Marc Van Leemputte, Peter Hespel, and Martine A. Thomis. "ACTN3 (R577X) genotype is associated with fiber type distribution." Physiological Genomics 32, no. 1 (December 2007): 58–63. http://dx.doi.org/10.1152/physiolgenomics.00173.2007.

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α-Actinin-3 is a Z-disc structural protein found only in type II muscle fibers. The X allele of the R577X polymorphism in the ACTN3 gene results in a premature stop codon and α-actinin-3 deficiency in XX homozygotes. Associations between the R577X polymorphism and the muscle-power performance of elite athletes have been described earlier. About 45% of the fiber type proportions are determined by genetic factors. The ACTN3 variant could be one of the contributing genes in the heritability of fiber type distribution through its interaction with calcineurin. The aim of this study was to quantify the association between the polymorphism and muscle fiber type distribution and fast-velocity knee extension strength. Ninety healthy young men (18–29 y) were genotyped for ACTN3 R577X. Knee extensor strength was measured isometrically (45°) and at different dynamic velocities (100–300°/s) on a programmable dynamometer. Twenty-two XX and twenty-two RR subjects underwent a biopsy of the right vastus lateralis muscle. Fiber type composition was determined by immunohistochemistry. Homozygotes for the R allele show significantly higher relative dynamic quadriceps torques at 300°/s, compared with XX carriers ( P < 0.05). Fiber type characteristics differed significantly between the two genotype groups. The percentage surface and number of type IIx fibers were greater in the RR than the XX genotype group ( P < 0.05), and α-actinin-3 protein content is systematically higher in type IIx compared with type IIa fibers (staining intensity ratio IIx to IIa = 1.17). This study shows that the mechanism, by which the ACTN3 polymorphism has its effect on muscle power, might rely on a control function of fiber type proportions.

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Xie, Sheng, Wanli Han, Xufan Xu, Guojun Jiang, and Baoqing Shentu. "Lateral Diffusion of a Free Air Jet in Slot-Die Melt Blowing for Microfiber Whipping." Polymers 11, no. 5 (May 2, 2019): 788. http://dx.doi.org/10.3390/polym11050788.

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In melt blowing, microfibrous nonwoven material is manufactured by using high-speed air to attenuate polymer melt. The melt-blown air jet determines the process of polymer attenuation and fiber formation. In this work, the importance of lateral velocity on the fiber was first theoretical verified. The lateral diffused characteristic of the air flow field in slot-die melt blowing was researched by measuring the velocity direction using a dual-wire probe hot-wire anemometer. Meanwhile, the fiber path was captured by high-speed photography. Results showed that there existed a critical boundary of the lateral diffusion, however, air jets in the x–z plane are a completely diffused field. This work indicates that the lateral velocity in the y–z plane is one of the crucial factors for initiating fiber whipping and fiber distribution.

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48

Canumalla, S., G. A. Gordon, and R. N. Pangborn. "In Situ Measurement of the Young’s Modulus of an Embedded Inclusion by Acoustic Microscopy." Journal of Engineering Materials and Technology 119, no. 2 (April 1, 1997): 143–47. http://dx.doi.org/10.1115/1.2805986.

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Alumina-silicate inclusions (shot) have been found to adversely affect the mechanical properties of a short alumina-silicate fiber reinforced aluminum alloy (A356). To better understand the differences between the responses of the shot and fibers to applied loads, the Young’s modulus of the shot is measured and compared to that of the fibers. The Rayleigh wave speed in the shot particle (cross-sectional area of 200 μm × 150 μm), measured in situ to be 4041 m/s using a scanning acoustic microscope, was used to calculate the Young’s modulus of the shot particle (132 GPa). The accuracy of the technique and the experimental arrangement used was verified to be better than four percent by independent measurements of the Rayleigh wave speeds in the aluminum alloy matrix and an embedded sapphire fiber. The fiber modulus was estimated to be 225 GPa based on a comparison of previously measured composite modulus with micromechanical predictions. Thus, shot was found to have a Young’s modulus 40 percent lower than that of the fibers. The applicability of the V(z) technique has been demonstrated for measuring the elastic properties over a microscopic area, even when the target material is an embedded inclusion.

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Kotynia, Renata, and Konrad Szczepański. "Analiza obliczeniowa dwuprzęsłowych belek betonowych zbrojonych prętami FRP według wybranych norm." BUILDER 286, no. 5 (April 29, 2021): 28–33. http://dx.doi.org/10.5604/01.3001.0014.8389.

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W artykule przedstawiono obliczeniową analizę nośności dwuprzęsłowych belek ze zbrojeniem kompozytowym z włókien szklanych i węglowych (Glass Fiber Reinforced Polymer – GFRP; Carbon Fiber Reinforced Polymer – CFRP) opracowaną na podstawie wybranych wytycznych normowych: Fib Bulletin 40, japońskiej – JSCE, amerykańskiej – ACI 440 oraz kanadyjskiej – ISIS z wynikami wybranych badań doświadczalnych. Głównym celem pracy jest określenie wpływu redystrybucji momentów przy obliczaniu nośności belek dwuprzęsłowych. Wyniki uproszczonej analizy obliczeniowej (bez wpływu redystrybucji momentów) pozwoliły porównać różne podejścia normowe oraz określić poziom zgodności wyników obliczeniowych z wynikami doświadczalnymi. W ten sposób można oszacować zakres bezpieczeństwa nośności na zginanie określony wpływem redystrybucji momentów względem wyników badań doświadczalnych.

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Tian, Fang, and Jun-Qian Zhang. "Three-Dimensional Numerical Simulation of Residual Stress of Z-Pin Composites During Curing Process." Science of Advanced Materials 12, no. 3 (March 1, 2020): 454–60. http://dx.doi.org/10.1166/sam.2020.3629.

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By using the coupled thermos-mechanical method, a three-dimensional finite element model of composite was established during the curing process. The accuracy of the simulation model was validated by performing a comparison with the literature results. Based on the model, a three-dimensional finite element method is applied to conduct analysis of the effect exerted by the curing related parameters on residual stresses in the curing process for the Z-pin AS4/3501-6 composite. The results indicate that the resin stress and fiber Z-direction stress increase with the curing process, especially during the cooling stage. The bottom stresses of both resin and fiber are observed to be lower than that of top layer. The stress of rich-resin zone at pin/fiber interface is higher but the deformation is smaller. The stress of resin and fiber increases as the volume shrinkage ratio of resin is on the rise.

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Journal articles on the topic 'Z-fiber'

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