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821.
Sara Asghari Mooneghi Ali Akbar Gharehaghaji Hossein Hosseini‐Toudeshky Giti Torkaman 《Polymer Engineering and Science》2015,55(8):1805-1811
Nanofiber yarns with twisted and continuous structures have potential applications in fabrication of complicated structures such as surgical suture yarns, artificial blood vessels, and tissue scaffolds. The objective of this article is to characterize the tensile fatigue behavior of continuous Polyamide 66 (PA66) nanofiber yarns produced by electrospinning with three different twist levels. Morphology and tensile properties of yarns were obtained under static tensile loading and after fatigue loading. Results showed that tensile properties and yarn diameter were dependent on the twist level. Yarns had nonlinear time‐independent stress–strain behavior under the monotonic loading rates between 10 and 50 mm/min. Applying cyclic loading also positively affected the tensile properties of nanofiber yarns and changed their stress–strain behavior. Fatigue loading increased the crystallinity and alignment of nanofibers within the yarn structure, which could be interpreted as improved tensile strength and elastic modulus. POLYM. ENG. SCI., 55:1805–1811, 2015. © 2014 Society of Plastics Engineers 相似文献
822.
Moradi Parisa Vafaee Yavar Mozafari Ali Akbar Tahir Nawroz Abdul-razzak 《SILICON》2022,14(16):10559-10569
Silicon - Salinity is one of the most crucial abiotic stresses, which is the consequence of an increase in the concentration of NaCl ions, influencing the plant’s growth, development, and... 相似文献
823.
824.
Silicon - The core/shell CaO@SiO2-SO3H nanoparticles were prepared by stabilizing of sulfonic acid on the surface of silica-coated CaO nanoparticles. The structure of CaO@SiO2-SO3H was... 相似文献
825.
Razieh Abdollahipour Khosro Khandani Ali Akbar Jalali 《Asian journal of control》2023,25(3):2020-2030
In this paper, the consensus problem in linear multi-agent systems with uncertain topology is investigated. The uncertainty in the communication topology is represented by granular fuzzy numbers obtained from expert knowledge, and the required calculations are performed with multidimensional relative–distance–measurement interval arithmetic. The concept of granular fuzzy graph and fuzzy Gershgorin disc theorem is introduced. Then a fuzzy consensus protocol is proposed for the multi-agent system with fuzzy granular uncertain topology. A two-step algorithm is also proposed to build the consensus protocol. We also propose a theorem for calculating the final value of fuzzy consensus, which shows the final value of consensus as a fuzzy number. Simulation results show the efficiency of the suggested algorithm. 相似文献
826.
Hadiqa Iqbal Tahira Mohsin Ali Saqib Arif Qurrat-ul-Ain Akbar Muhammad Saeed 《International Journal of Food Science & Technology》2023,58(1):473-481
Red rice, rich in fibre and phenolic contents, is one of the underutilised grains. Therefore, the present study developed the wheat/red rice flour (RRF) composites followed by its utilisation in pan breads. It led to an increase in ash and fibre contents of resultant flour combinations, but gluten network became weaker. The values for water absorption were unaffected with RRF replacements ≤15% of wheat flour. Moreover, the proximate estimates of RRF added breads demonstrated increased moisture and fibre contents. Substituted bread combinations were harder with increased gumminess and springiness values; however, cohesion decreased. The per cent change in cohesion and hardness of individual breads upon storage was lesser in composites compared to control suggesting decline in staling phenomenon. Nutritional assessment of both RRF containing flour and breads showed higher total phenolic content and DPPH radical scavenging activity compared to their respective controls. Composite breads also demonstrated reduced glycaemic index suggesting its importance for diabetic patients. 相似文献
827.
Enkhbayar Enkhtuvshin Sunghwan Yeo Hyojeong Choi Kang Min Kim Byeong-Seon An Swarup Biswas Yongju Lee Arpan Kumar Nayak Jin Uk Jang Kyeong-Han Na Won-Youl Choi Ghulam Ali Keun Hwa Chae Muhammad Akbar Kyung Yoon Chung Kyoungmin Yoo Yong-Chae Chung Tae Ho Shin Hyeok Kim Chan-Yeup Chung HyukSu Han 《Advanced functional materials》2023,33(22):2214069
Generation of hydrogen fuel via electrochemical water splitting powered by sustainable energy, such as wind or solar energy, is an attractive path toward the future renewable energy landscape. However, current water electrolysis requires desalinated water resources, eventually leading to energy costs and water scarcity. The development of cost-effective electrocatalysts capable of splitting saline water feeds directly can be an evident solution. Herein, a surface reconstructed nickel-iron layered double hydroxide (NF-LDH) is reported as an exceptionally active and durable bifunctional electrocatalyst for saline water splitting without chloride corrosion. The surface reconstructed NF-LDH consists of Ni3Fe alloy phase interconnected in a 2D network in which an ultrathin (≈2 nm) and low-crystalline NiFe (oxy)hydroxide phase are formed on the surface. The NiFe (oxy)hydroxide phase draws large anodic current densities, satisfying the level of practical application, while the Ni3Fe alloy phase is simultaneously responsible for the high catalytic activity for cathodic reactions and superior corrosion resistance. The surface reconstructed NF-LDH electrode can be easily fabricated in a large electrode area (up to 25 cm2) and can successfully produce hydrogen fuels from saline water powered by the laboratory-made low-intensity photovoltaic cell. 相似文献
828.
Ezgi Bütev Öcal Seyed Vahid Sajadifar Erik P. K. Sellner Malte Vollmer Akbar Heidarzadeh Janez Zavašnik Thomas Niendorf Peter Groche 《Advanced Engineering Materials》2023,25(15):2201879
Herein, functionally graded AA7075 components manufactured via hot stamping are investigated by focusing on the effect of different process variables on localized microstructure evolution. To realize gradation through stamping, an active tool is designed and applied. The design of experiments allows to assess the impact of transfer time from the furnace to the tool, quenching time in the tool, and final quenching media. Related characteristics of mechanical properties throughout the hat-shaped profile are assessed via hardness and tensile tests. As expected, the sections of the samples formed in the cooled part of the tool are characterized by higher mechanical strength following subsequent aging, while sections formed in the heated part exhibit higher ductility. Moreover, the microstructural analysis reveals that fine precipitates with minimum interparticle distances only form in the cooled section of the samples. Increasing the tool temperature at the heated side to 350 °C results in the formation of coarse precipitates in the grain interior and along the grain boundaries. A sharp gradient in terms of microstructural and mechanical properties is found between these conditions. After reducing the transfer time, an increased volume fraction of fine precipitates leads to further improvements in hardness and mechanical strengths. 相似文献
829.
Very fine alumina nanoparticles were loaded in novolac type phenolic resin (PF) using solution mixing method. The concentration of nanoalumina in PF was varied between 2.5 to 20 wt%. All the compounds were compression molded and then subjected to scanning electron microscopy (SEM), tensile, flexural, and dynamic mechanical analysis (DMA) tests. SEM analysis showed that the nanoalumina were dispersed uniformly at low concentrations, however, at high concentrations, dispersion was suppressed leading to agglomerates in the composites. Mechanical testing revealed that the nanoalumina had a great influence on the strength and stiffness of PF resin particularly at concentrations below 5 wt%. However, at concentration above 5 wt%, the stress concentrations were developed because of the formation of big aggregates that results in strength reduction. Theoretical analyses based on Pukanszky and micromechanical models of tensile modulus revealed that strong interfacial interaction and thick interphase region around the alumina nanoparticles is formed. DMA results suggested that the nanoalumina increased the crosslinking density of the PF resin, possibly around the interface region. It was also postulated that an apparent percolation state is established above 5 wt% loading of nanoalumina in which interphase region comes to contact before direct contact of particle leading to continuous interphase region. POLYM. COMPOS., 35:1285–1293, 2014. © 2013 Society of Plastics Engineers 相似文献
830.
Abdul Rehman Akbar Gangqiang Peng Yongyi Li Rashid Iqbal Adil Saleem Guohong Wang Abdul Sammed Khan Mumtaz Ali Muhammad Tahir Mohammed A. Assiri Ghaffar Ali Fude Liu 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(44):2304686
The fabrication of low-cost, effective, and highly integrated nanostructured materials through simple and reproducible methods for high-energy-density supercapacitors is highly desirable. Herein, an activated carbon cloth (ACC) is designed as the functional scaffold for supercapacitors and treated hydrothermally to deposit NiCo nanoneedles working as internal core, followed by a dip-dry coating of NiOOH nanoflakes core–shell and uniform hydrothermal deposition of CoMoO4 nanosheets serving as an external shell. The structured core–shell heterostructure ACC@NiCo@NiOOH@CoMoO4 electrode resulted in exceptional specific areal capacitance of 2920 mF cm−2 and exceptional cycling stability for 10 000 cycles. Moreover, the fabricated electrode is developed into an asymmetric supercapacitor which demonstrates excellent areal capacitance, energy density, and power density within the broad potential window of 1.7 V with a cycling life of 92.4% after 10 000 charge–discharge cycles, which reflects excellent cycle life. The distinctive core–shell structure, highly conductive substrate, and synergetic effect of coated material results in more electrochemical active sites and flanges for effective electrons and ion transportation. This unique technique provides a new perspective for cost-efficient supercapacitor applications. 相似文献