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951.
Recent development and challenges of multifunctional structural supercapacitors for automotive industries
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Biplab K. Deka Ankita Hazarika Jisoo Kim Young‐Bin Park Hyung Wook Park 《国际能源研究杂志》2017,41(10):1397-1411
In the last decades, fuel scarcity and increasing pollution level pave the way for an extensive interest in alternatives to petroleum‐based fuels such as biodiesel, solar cells, lithium ion batteries, and supercapacitors. Among them, structural supercapacitors have been considered as promising candidates for automotive industries in present time. Herein, the use of carbon fiber‐based supercapacitors in automotive applications is reviewed. Carbon fiber is an excellent candidate for vehicle body applications, and its composites could be widely used in the development of supercapacitors that could provide both structural and energy storage functions. Different surface modification processes of the carbon fiber electrode to enhance the electrochemical as well as mechanical performances are discussed. The advantages of the glass fiber separator and its comparison with other types of dielectric media have been incorporated. The synthesis procedures of the multifunctional solid polymer electrolyte and its significance have been also elaborated. The fabrication process, component selection, limitations, and future challenges of these supercapacitors are briefly assimilated in this review. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
952.
The diffusion dynamics of the cellulose/1-allyl-3-methylimidazolium chloride ([Amim]Cl) solution during coagulation of regenerated cellulose fiber in a nonsolvent bath was investigated in detail. According to Fick's second law of diffusion, the experimental data were fitted to obtain the diffusion coefficients of [Amim]Cl (D). The cellulose concentration, bath type, and temperature were varied to analyze their influence on the diffusion coefficient of [Amim]Cl. Furthermore, the dependence of the structure and properties of the regenerated fiber obtained via dry-jet-wet spinning on the diffusion coefficients were analyzed. Many defects were formed in the surface and cross sections of the regenerated fibers prepared with high diffusion coefficients. The crystallization and mechanical properties deteriorated with the increase in the diffusion rate of [Amim]Cl. Therefore, the diffusion coefficients of [Amim]Cl should be kept relatively low to enable the preparation of uniform-structured regenerated cellulose fibers. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47609. 相似文献
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Lutfiye Altay Ebru Bozaci Metehan Atagur Kutlay Sever Gozde Sevig Tantug Mehmet Sarikanat Yoldas Seki 《应用聚合物科学杂志》2019,136(9):47131
To increase the mechanical properties of recycled carbon fiber-reinforced polypropylene (PP) composites, recycled carbon fibers (RCF) were subjected to atmospheric plasma treatment at different plasma powers (100, 200, and 300 W). The changes on surface topography and roughness of RCF were examined by atomic force microscopy. Plasma treatment of RCF increased the roughness value of RCF. The variation of surface elemental compositions and tensile strength of RCF were determined by using X-ray photoelectron spectroscopy and tensile test, respectively. Plasma-treated RCF-reinforced PP composites were fabricated using high speed thermo-kinetic mixer. Plasma treatment of RCF at 100 W increased the tensile and flexural strength values of RCF-reinforced PP composites considerably by 17 and 11%, respectively. However, plasma treatment of RCF at higher plasma powers (200 W and 300 W) decreased tensile and flexural strength values of composites because of the etching of RCF. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47131. 相似文献
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This paper studies the fatigue behavior of basalt fiber reinforced epoxy polymer (BFRP) composites and reveals the degradation mechanism of BFRP under different stress levels of cyclic loadings. The BFRP composites were tested under tension–tension fatigue load with different stress levels by an advanced fatigue loading equipment combined with in-situ scanning electron microscopy (SEM). The specimens were under long-term cyclic loads up to 1 × 107 cycles. The stiffness degradation, S–N curves and the residual strength of run-out specimens were recorded during the test. The fatigue strength was predicted with the testing results using reliability methods. Meanwhile, the damage propagation and fracture surface of all specimens were observed and tracked during fatigue loading by an in-situ SEM, based on which damage mechanism under different stress levels was studied. The results show the prediction of fatigue strength by fitting S–N data up to 2 × 106 cycles is lower than that of the data by 1 × 107 cycles. It reveals the fatigue strength perdition is highly associated with the long-term run-out cycles and traditional two million run-out cycles cannot accurately predict fatigue behavior. The SEM images reveal that under high level of stress, the critical fiber breaking failure is the dominant damage, while the matrix cracking and interfacial debonding are main damage patterns at the low and middle fatigue stress level for BFRP. Based on the above fatigue behavior and damage pattern, a three stage fracture mechanism model under fatigue loading is developed. 相似文献
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This work presents the preliminary results of an experimental investigation on the mechanical behavior of self-consolidating concrete reinforced with hybrid steel fibers in the material and structural scale. Straight and hooked end steel fibers with different lengths and diameters were used as reinforcement in fiber volume fractions of 1.0 and 1.5%. In the fresh state the concrete was characterized using the slump flow, L-box and V-funnel tests. To determine the effect of the hybrid reinforcement on the plastic viscosity and shear yield stress a parallel plate rheometer was used. Following, the mechanical response was measured under tension and bending tests. In the flexural test, the movement of the neutral axis was experimentally determined by strain-gages attached to compression and tensile surfaces. Furthermore, the mechanical response of the material under bi-axial bending was addressed using the round panel test. During the test the crack opening was measured using three linear variable differential transformers (LVDT’s). The cracking mechanisms were discussed and compared to that obtained under four point bending and direct tension. The obtained results indicated that the fiber hybridization improved the behavior of the composites for low strain and displacement levels increasing the serviceability limit state of the same through the control of the crack width. For large displacement levels the use of the longer fibers led to a higher toughness but with an expressive crack opening. Due to its structural redundancy the round panel test allowed the formation of a multiple cracking pattern which was not observed in the four point beam tests. Finally, the obtained material’s properties were used in a nonlinear finite element model to simulate the round panel test. The simulation reasonably agreed with the experimental test data. 相似文献
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960.
Deep‐black‐coloring effect of fabrics made of noncircular cross‐section polyester filaments
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The effects of noncircular cross‐section (NCCS) poly ethylene terephthalate (PET) filaments and its shape factor on deep‐black‐coloring of dyed fabrics were investigated by comparing to that of the circular cross‐section PET ones. Indexes such as K/S, L* and Integ values were used for characterizing the deep‐black‐coloring effect on fabrics. The results indicated that fabrics made with NCCS PET filaments exhibited good deep‐black‐coloring effects. The calculated shape factor of the NCCS PET fiber had a significant correlation with the degree of deep‐black‐coloring exhibited by the fabric made from the fibers. A qualitative optical analysis of the NCCS PET fibers was carried out to explain the causes of the deep‐coloring of the NCCS fibers. This analysis implies that the contours of the NCCS fiber composed of surfaces with varied curvature increase the scattering of light by lowering specular reflection and increasing interior reflected and refracted light. This, in turn, strengthens the deep‐coloring effect. © 2013 Wiley Periodicals, Inc. Col Res Appl, 39, 511–518, 2014 相似文献