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《International Journal of Hydrogen Energy》2019,44(59):31230-31238
Hydrogen gas has been considered as one of the promising sources of energy. Thus, several strategies including the hydrolysis of hydrides have been reported for hydrogen production. However, effective catalysts are highly required to improve the hydrogen generation rate. Two dimensional metal-organic frameworks (copper-benzene-1,4-dicarboxylic, CuBDC), and CuBDC-derived CuO@C were synthesized, characterized and applied as catalysts for hydrogen production using the hydrolysis and methanolysis of sodium borohydride (NaBH4). CuBDC, and CuO@C display hydrogen generation rate of 7620, and 7240 mlH2·gcat−1· min−1, respectively for hydrolysis. While, CuBDC offers hydrogen generation rate of 9060 mlH2·gcat−1· min−1 for methanolysis. Both catalysts required short reaction time, and showed good recyclability. The materials may open new venues for efficient catalyst for energy-based applications. 相似文献
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本文分别比较了茶黄素(TFs)与黑木耳多糖(AAP)和灵芝孢子多糖(GLP)单一、联合使用清除ABTS自由基活性的作用。采用Chou-Talaly联合指数(CI)方法分析ABTS自由基清除实验结果,并对单一和联合使用的清除效果、联合指数(CI)、等效应图和剂量减少指数(DRI)进行分析评价。单独使用茶黄素、黑木耳多糖和灵芝孢子多糖的IC50值分别为20.60μg/mL、2.49 mg/mL和0.93 mg/mL,联合使用茶黄素和黑木耳多糖与茶黄素和灵芝孢子多糖(质量比为1:3)后,IC50值分别为74.04μg/mL和58.92μg/mL。联合指数(CI)分析表明,从清除率5%到97%,茶黄素和灵芝多糖的联合指数都小于1,且CI有降低趋势,二者间有协同作用;剂量减少指数(DRI)分析显示,从清除率5%到97%,茶黄素和灵芝多糖的剂量减少指数都大于1,以上结果茶黄素和黑木耳多糖联合使用均表现不一致。茶黄素和灵芝多糖之间存在协同清除ABTS自由基效应,但茶黄素和黑木耳多糖不存在。 相似文献
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Qimin Cui Yudan Wang Wenbing Zhou Shuyue He Meilian Yang Qingwang Xue Yifen Wang Tianrui Zhao Jianxin Cao Afsar Khan Guiguang Cheng 《International Journal of Food Science & Technology》2021,56(9):4807-4819
The present study is aimed to evaluate the effect of three different drying methods, including shade drying (SD), freeze drying (FD) and hot air dying (HAD), on the chemical components, antioxidant and cytoprotective activities of aqueous-methanol extracts from A. fragrans leaves. The total phenolic and flavonoid content were determined by spectroscopic methods, whereas the chemical profile of different extracts was determined by ultra-high-performance liquid chromatography coupled with a tandem mass spectrometry (UHPLC-MS/MS). A total of thirteen compounds were characterised and 9 phenolic compounds have been quantified. Two dihydrochalcone glycosides named confusoside and vacciniifolin were found to be the most abundant phenolic compounds in the SD extract of A. fragrans leaves, which also showed the strongest antioxidant and cytoprotective activities. The results showed that shade drying is an efficient method for preserving the chemical constituents and maintaining the antioxidant and cytoprotective activities of A. fragrans leaves. 相似文献
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《Ceramics International》2017,43(2):2136-2142
ZnFe2O4-graphene composite nanofibers were prepared through electrospinning technique, then with graphene oxide by the facile solvothermal method to get the final products for the first time. The obtained ZnFe2O4 nanofibers composed of numerous same size nanoparticles wrapped by graphene sheets to form a unique nanostructure. When the ZnFe2O4-graphene electrode was evaluated as anode for lithium-ion batteries, good rate capability and long-term cycling stability could be achieved. The ZnFe2O4-graphene electrode exhibited a first discharge capacity of 2166 mAh g−1 cycling at 0.05 C, remained an average reversible capacity of 1000 mAh g−1 after 50 cycles, and kept the high rate capacities of 899, 822, 760 and 711 mAh g−1 at the current rates of 0.5, 1, 2 and 5 C, respectively. The excellent electrochemical performance could be ascribed to the following reasons: the large electrochemical active surface area provided by the composite nanofibers; the graphene sheets decreased the internal resistance of the lithium-ion batteries, which resulted from the electrical conductivity of the graphene sheets; the graphene sheets as conductive network could effectively restrain the agglomeration of ZnFe2O4 nanopaiticals. 相似文献
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主要综合了鲁西一带利用传统方法制作白菜豆豉的一种工艺,在此基础上,对工艺配方、技术参数进行了改进,显著提高了产品的色香味,并经过真空包装热杀菌处理,使产品由一季食用变四季消费。 相似文献
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超声波辅助双水相提取条斑紫菜黄酮类物质及其抗氧化活性研究 总被引:1,自引:0,他引:1
利用超声波辅助丙醇-硫酸铵双水相体系提取紫菜中总黄酮,并优化提取条件,测定总黄酮提取物对羟自由基(·OH)的抑制活性。结果表明:本方法可有效地从紫菜中提取总黄酮,紫菜总黄酮提取率为0.148%,明显高于乙醇-水回流提取法。最优提取条件为醇水比为0.6、硫酸铵质量浓度0.30g/mL、超声时间20min、料液比0.04。紫菜中含有较丰富的黄酮类物质,提取物对·OH具有良好的抑制作用,是一种有效的天然自由基清除剂,具有很大的开发利用前景。 相似文献