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81.
Statistical characteristics of wind in Saudi Arabia 总被引:1,自引:0,他引:1
82.
Jamil Ahmad Wajahat Ur Rehman Shaik Khadheer Basha Basheer Ahamed Kuppanna Chidambaram 《Polymer-Plastics Technology and Engineering》2019,58(4):366-383
Polyamide-b-ethylene (Pebax) is a promising material for membrane-based gas separation application with excellent CO2 capturing potential. Pebax is a rubbery elastomer which offers good mechanical support with its hard crystalline phase and excellent gas transport through its amorphous polyether phase. This review article includes recent advances in Pebax based membrane synthesis, solvent selection for membrane synthesis, compatible fillers with Pebax matrix and the improved gas separation performance of the prepared membranes. The literature review shows that Pebax based membranes are a good candidate for separation of CO2 from flue gases and can be used for commercial applications. 相似文献
83.
Kashif Iqbal Asfandyar Khan Danmei Sun Munir Ashraf Abdur Rehman Faiza Safdar 《纺织学会志》2019,110(4):625-638
Phase change materials (PCMs) are widely being used in thermal energy storage systems for solar engineering, building materials, heat pumps, spacecraft, and in textile field especially smart and technical textiles. There are large numbers of organic and inorganic PCMs that possess a wide range of melting and solidifying temperature which attracts researcher’s attention for their applications in different fields. This review paper summarizes the investigation and analysis of the available organic and inorganic PCMs, different encapsulating techniques, characterization techniques, incorporation into fiber and pad application on textiles with practical applications in the field of smart textiles. 相似文献
84.
The effect of roasting on the phenolic components of Australian wattle (Acacia victoriae Bentham) seed was investigated. Wattle seeds were roasted at 200 °C for 5–30 min and ground to flour, which were then extracted with 70% acetone. The total phenolic and flavonoid contents of the extracts were determined, and the phenolic components were analysed by reverse phase-high performance liquid chromatography (RP-HPLC) coupled with an on-line post-column reaction system to determine the active antioxidant peaks. The major peaks were then purified by preparative HPLC and identified by gas chromatography–mass spectrometry (GC–MS) analysis. Roasting of wattle seeds resulted in significant increases in its soluble phenolic content. The concentration of total phenolics and flavonoids in the seeds roasted for 30 min was more than nine and four times higher, respectively, than that in the raw seeds. The major phenolic acids present in wattle seeds were found to be succinic and gallic acids, the concentration of which increased by up to 10-fold as a result of roasting. 相似文献
85.
In the present numerical study, the combined effect of temperature-dependent thermal conductivity, linear thermal radiation, and magnetic effect on shear-thinning tangent hyperbolic fluid past a sensor surface has been studied. After converting the modelled partial differential equations into ordinary differential equations by using similarity transformation, the system of equations is tackled with the aid of the shooting method. The influence of important parameters on the fluid motion and energy distribution is displayed graphically and analyzed in detail. The presented simulations depict that a significant rise in fluid velocity is noticed for an enhancement in the magnetic parameter while an opposite trend is observed for the temperature distribution. Moreover, the skin friction coefficient decreases as the squeezed flow index is increased. 相似文献
86.
Abdul Rehman Akbar Huihui Hu Muhammad Bilal Qadir Muhammad Tahir Zubair Khaliq Zhikang Liu Chuanxi Xiong Quanling Yang 《Ceramics International》2021,47(4):4648-4658
Technical development in electronic devices is frequently stifled by their insufficient capacity and cyclic stability of energy-storage devices. The nano-structured materials have sensational importance for providing novel and optimized combination to overcome exiting boundaries and provide efficient energy storage systems. Metal hydroxide materials with high capacity for pseudo-capacitance properties have grabbed special attention. Lately, the blend of nickel and cobalt hydroxides has been considered as a favorable class of metallic hydroxide materials owing to their comparatively high capacitance and exceptional redox reversibility. The sulfonated carbon nanotube fluid (SCNTF) was prepared by the ion exchange method to be utilized as the exceptional templates due to astonishing specific surface area, ensuring the maximum utilization of the active material. The CoNi-layered double hydroxides (LDHs)/SCNTF core-shell nanocomposite was prepared by the simple solvothermal method. Structural analysis showed that the composite material had the high conductance of carbon materials, the pseudo-capacitance characteristics of metal hydroxides, and porous structure, which facilitates the ion shuttle when the electrolyte reacts with the active material. Electrochemical analysis results showed that CoNi-LDHs/SCNTF had excellent rate performance, reversible charge-discharge properties and cycle stability. It exhibited an extreme specific capacity of 1190.5 F g?1 at a current density of 1 A g?1; whereas specific capacity remained 953.7 F g?1 at the current density was 10 A g?1. In addition, the capacity retention rate after 5000 charge-discharge cycles at a current density of 20 A g?1 was 81.0%. The results indicated that the CoNi-LDHs/SCNTF core-shell nanocomposite material is cost efficient and an effective substitute in energy storage applications. 相似文献
87.
This paper examines two needle-punched geosynthetic clay liners' water retention behaviour at high suction ranges using the vapour equilibrium technique where super-saturated salt solutions controlled the relative humidity. This study shows that the bentonite form and its mineralogy affect the absorption/desorption of GCLs and their corresponding water retention curves. In particular, a granular bentonite-based GCL was found to absorb more and release less water than a powdered bentonite-based GCL due to its higher montmorillonite content and larger pores. The water retention curves of both GCLs exhibited very little hysteretic behaviour at high suction. Repeated wetting-drying cycles shifted the WRCs of both GCLs slightly downward with minimal impact on their degree of hysteresis. 相似文献
88.
89.
90.
Li Xiang Jiang Qing-Zheng Rehman Sajjad Ur Huang Qing-Fang Chen You-Wei Zhao Chuan-Jia Zhong Zhen-Chen 《Journal of Superconductivity and Novel Magnetism》2022,35(1):251-259
Journal of Superconductivity and Novel Magnetism - NdFeB hot-pressed and hot-deformed magnets were prepared by hot-pressed (HP) sintering and spark plasma sintering (SPS). The effects of sintering... 相似文献