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排序方式: 共有2294条查询结果,搜索用时 15 毫秒
1.
《International Journal of Hydrogen Energy》2022,47(6):3580-3586
Renewable electricity-powered hydrogen production is an attractive alternative to unsustainable industrial processes, but the large-scale implantation of such sustainable technology still requires efficient and noble-metal-free electrocatalysts for driving cathodic hydrogen evolution reaction (HER), especially under alkaline conditions. In this paper, CoP nanowire array was in-situ developed on porous graphite felt (CoP/GF) as a new 3D electrocatalyst in facilitating hydrogen evolution electrocatalysis. This CoP/GF presents outstanding HER activity, requiring a low overpotential of 130 mV to deliver a current density of 20 mA cm?2 as tested in 1.0 M KOH. Furthermore, this free-standing catalyst exhibits impressive long-term durability of up to 50 h under working conditions. 相似文献
2.
《International Journal of Hydrogen Energy》2019,44(27):14157-14163
In this study, known electrocatalytic active metal nickel and low amount of gallium were electrodeposited on carbon felt electrode for hydrogen evolution reaction in alkali medium. Morphological and structural analyses of prepared electrodes were determined by scanning electron microscopy and energy dispersive X-ray spectroscopy. The electrocatalytic activity of obtained electrodes for hydrogen evolution reaction was determined with cathodic polarization curves, electrochemical impedance spectroscopy, discharge potential measurements, hydrogen volume measurements at constant potential and durability tests. It was found that the electrodeposition of low amount of gallium over the nickel coated carbon felt electrode increases the hydrogen evolution reaction activity and decreases the overpotential for hydrogen region. The electrocatalytic activity of nickel and gallium deposited on carbon felt electrode was explained with active sites of surface and synergistic effect of nickel and gallium created by high surface area of carbon felt. 相似文献
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用毛用活性染料德龙素红CE对羊毛线进行染色,探讨了HAc用量、(NH4)2SO4用量、染色温度、染色时间、助剂对染色上染率、固色率和耐皂洗色牢度的影响。结果表明:德龙素红CE染羊毛线的优化工艺为HAc 1.0%~1.5%(omf)、(NH4)2SO43.0%~4.0%(omf)、平平加O 1.0%~1.5%(omf)、染色温度85℃、染色时间60~70 min、羊毛线2 g、浴比1∶50;上染率为95%~96%,固色率为94%~95%,耐皂洗色牢度的变色、沾色均为4~5级。 相似文献
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Shahid Adeel Shazia Anwar Bukhari Khadija Kareem Fazal-ur- Rehman Atya Hassan 《Journal of Natural Fibers》2020,17(5):635-649
ABSTRACTFood products as a source of natural colorants are gaining widespread popularity around the globe due to their ayurvedic and eco-friendly nature. Current study is aimed with the utilization of food products (Saffron and madder) as a source of dye for woolen yarn. It is found that, for Saffron, irradiation of yarn for 6 min gives high color strength by dyeing for 45 min in the presence of 2% of salts using un-irradiated dye bath of 1 pH, whereas for madder, 4 min is optimal irradiation time for extract to dye irradiated yarn for 25 min in the presence of 6% of salts using the irradiated dye bath of pH 1. The mordanting carried out at optimal conditions show that using both extracts, woolen yarn dyed at optimal conditions has given good color characteristics. It is concluded that microwave radiation has not only improved natural dyeing process but also make the process more eco-friendly and sustainable as well. 相似文献
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利用简单的一步水热法制备了MoS2纳米片并用于修饰不锈钢纤维毡阳极(MoS2-SSFF),与未修饰不锈钢纤维毡阳极(SSFF)和多壁碳纳米管修饰阳极(CNT-SSFF)进行了对比研究。装配MFC运行的测试结果表明,MoS2-SSFF/MFC的功率密度为714 m W/m2,略高于CNT-SSFF/MFC的功率密度693 m W/m2,远高于未修饰SSFF/MFC的功率密度197 m W/m2。利用扫描电子显微镜(SEM)观察到MoS2纳米片呈簇状附着于MoS2-SSFF电极表面,显著增加了电极的比表面积。MoS2纳米片修饰改善了SSFF阳极的生物相容性,修饰电极在循环伏安测试(CV)中表现出良好的氧化还原性能。水热法制备的MoS2纳米片用于修饰阳极是一种高效、经济、简单的阳极修饰方法。 相似文献
8.
Zhi-Jia Xu Song Yang Guang-Hua Hu Qing-Hui Wang Jing-Rong Li 《International Journal of Hydrogen Energy》2018,43(9):4355-4370
A macroscopic numerical method is proposed to study the flow distribution uniformity of a novel porous copper fiber sintered felt (PCFSF), which has gradient porosities and was developed as the methanol steam reforming micro-reactor catalyst support for hydrogen production for fuel cell applications. The macroscopic porous media developed by the ANSYS/FLUENT software is used to represent the PCFSF. Our results indicate that the gradient porosity can reshape the flow distribution of PCFSFs greatly, thus producing significant influence on their performance. It is further revealed that, for a PCFSF with a determined gradient porosity configuration but different reactant feed directions, the velocity uniformity can be used as a quantitative criterion to evaluate the performance of hydrogen production. Furthermore, new gradient PCFSFs are produced according to the flow distribution of original gradient PCFSFs. The preliminary experimental results of the new gradient PCFSFs of 0.8-0.9-0.7 and 0.7-0.9-0.8 exhibit better methanol conversion and H2 flow rate. This indicates that the numerical method can be used for the optimization of PCFSFs' gradient porosity configuration, which consists of the shape and position of the interfaces between different porosity portions, the number of interfaces and the porosity distribution in different portions. 相似文献
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The aim of the study is to investigate the optimum dyeing conditions for wool and cotton fabrics with the nettle (Urtica dioica L.) extract. For this purpose, the leaves of the nettle were extracted with distilled water by using Soxhlet apparatus. Wool and cotton fabrics were pretreated with artificial animal urine system (AAUS) including NH3 (3%, v/v), CaC2O4 (3%, m/v), and urea (3%, m/v) before dyeing processes in order to improve the fastness properties of the dyed samples. The best dyeing conditions were evaluated in terms of color strength. The results reveal that the nettle leaves shall probably be an important raw material especially for dyeing of wool fibers. 相似文献