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Wei Peng Min Luo Xiandong Xu Kang Jiang Ming Peng Dechao Chen Ting‐Shan Chan Yongwen Tan 《Liver Transplantation》2020,10(25)
The electrochemical nitrogen reduction reaction (NRR) process usually suffers extremely low Faradaic efficiency and ammonia yields due to sluggish N?N dissociation. Herein, single‐atomic ruthenium modified Mo2CTX MXene nanosheets as an efficient electrocatalyst for nitrogen fixation at ambient conditions are reported. The catalyst achieves a Faradaic efficiency of 25.77% and ammonia yield rate of 40.57 µg h?1 mg?1 at ‐0.3 V versus the reversible hydrogen electrode in 0.5 m K2SO4 solution. Operando X‐ray absorption spectroscopy studies and density functional theory calculations reveal that single‐atomic Ru anchored on MXene nanosheets act as important electron back‐donation centers for N2 activation, which can not only promote nitrogen adsorption and activation behavior of the catalyst, but also lower the thermodynamic energy barrier of the first hydrogenation step. This work opens up a promising avenue to manipulate catalytic performance of electrocatalysts utilizing an atomic‐level engineering strategy. 相似文献
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The Chinese black truffle Tuber indicum is commercially valuable. The main factors influencing the success or failure of a truffle crop include the mycorrhizal colonization rate and host plant quality. The effects of a plant growth regulator (uniconazole) and plant growth management technique (root-tip cutting) on T. indicum colonization rate and Pinus armandii seedling growth were assessed under greenhouse conditions. The results indicated that 10 mg l−1 uniconazole or the combination of 5 mg l−1 uniconazole and root-tip cutting constitutes an effective method for ectomycorrhizal synthesis based on an overall evaluation of colonization rate, plant biomass, plant height, root weight, stem circumference and antioxidant enzyme activities (SOD and POD) of P. armandii. The abundance of Proteobacteria in the rhizosphere of colonized seedlings might serve as an indicator of stable mycorrhizal colonization. This research inspires the potential application of uniconazole and root-tip cutting treatments for mycorrhizal synthesis and truffle cultivation. 相似文献
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Ao Tan Rio Suzuki Chikako Yokoyama Shigekazu Yano Hiroyuki Konno 《Journal of peptide science》2020,26(10)
A novel antimicrobial peptide derived from ovalbumin has been discovered. First, the peptide fragment RKIKVYLPRMK (TK9.1) was identified based on computerized predictions of the secondary structure of peptides in a protein data bank. Using HeliQuest, the sequence was developed into RKIKRYLRRMI (TK9.1.3), which was synthesized using Fmoc‐solid phase peptide synthesis, and found to have strongly antimicrobial activity against Gram‐positive and Gram‐negative bacteria, and fungi but not cytotoxic to HeLa cells and hemolysis in mouse red blood cells. Although ovalbumin itself does not have an antibacterial activity, our results suggest that it may supply the organisms that consume it with antimicrobial peptides, in support of their immunodefence. 相似文献