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Chengjing Mi Yanping Huang Fengtao Chen Kui Wu Weiyan Wang Yunquan Yang 《International Journal of Hydrogen Energy》2021,46(1):875-885
Methylcyclohexane is a very promising liquid organic hydrogen carrier, but its dehydrogenation mechanism on Pt-based bimetallic catalysts is not yet clear. In order to understand the catalytic dehydrogenation of methylcyclohexane on Ni–Pt(111), DFT calculations were performed and the calculation results were compared with the corresponding values on Pt(111). It is shown that because the electronegativity of Ni atoms is less than that of Pt atoms, electrons transfer from Ni atoms to Pt atoms. Compared with Pt(111), the binding energy (the absolute value of the adsorption energy) of related species on Ni–Pt(111) surface was smaller, indicating that the binding strength between these species and the surface metal atoms on Ni–Pt(111) is weaker. In the stable adsorption configurations on Ni–Pt(111), almost all the metal atoms forming chemical bonds with the adsorbates were Pt atoms, indicating that Pt was the main active component. Although the actual catalytic reaction is more complicated, this study provided some insights into one of the important aspects. 相似文献
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Mengjian Hao Tiantian Yi Yongfan Cao Yinmin Song Zhenzhu Cao Weiyan He Yanfang Gao Jinrong Liu 《Advanced Powder Technology》2019,30(1):111-119
AgI/BiOCOOH composite photocatalysts have been synthesized via a simple deposition-precipitation method. The crystal structure, microstructure, element valance, light and electrical properties of as prepared samples were characterized by XRD, SEM, TEM, XPS, UV–Vis DRS, PL, EIS and photocurrent response. The loading of AgI nanoparticles endowed BiOCOOH with good visible light absorption and photocatalytic activity for degrading rhodamine B. The composition with Ag:Bi?=?1:1 exhibited the best photocatalytic activity. The enhanced photocatalytic performance could be mainly attributed to the effective separation of the photogenerated carriers at the heterojunction. O2? and h+ were suggested as the main reactive species in the photocatalytic reaction. In addition, the photocatalysts showed excellent stability over multiple reaction cycles. 相似文献
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以含锌磷化渣为原料,先用氢氧化钠浸取制得磷酸钠溶液,再采用萃取法去除该溶液中的微量锌,在净化液中加入六水合氯化铁反应制得磷酸铁产品。实验结果表明:采用氢氧化钠浸取磷化渣,能有效地去除磷化渣中的金属离子,获得含微量锌的磷酸钠溶液,磷酸根的浸取率可达93.97%,磷酸根的总利用率可达78.31%;采用双硫腙与P204萃取剂对该溶液进行萃取,其双萃取剂混合萃锌效果明显优于它们相应的单种萃取剂萃锌效果。在有机相与水相体积比=1∶5时,锌的单级萃取率可达55.39%,产品磷酸铁中锌含量低于30.0 μg/g。研究表明,采用氢氧化钠浸取和双硫腙与P204双萃取剂除杂的方法,可有效回收含锌磷化渣中的磷酸根并制备出电池级磷酸铁。 相似文献
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采用硫酸亚铁和过氧化氢所构成的Fenton试剂,对经生化处理后的焦化废水进行Fenton高级氧化深度处理,重点考察了废水初始pH,FeSO4·7H2O、H2O2及PAM投加量对焦化生化废水处理效果的影响。结果表明,采用Fenton高级氧化法可使经生化处理后的焦化废水中的COD、NH3-N和色度得到进一步有效去除。对于中等浓度的焦化生化废水,较适宜的Fenton氧化工艺条件:废水初始pH为8~10,FeSO4·7H2O投加量为500 mg/L,H2O2投加量为3.5 mL/L,PAM投加量为4.0 mg/L。在此条件下,COD、NH3-N和色度的去除率分别可达85.9%、97.3%和84.6%。 相似文献
6.
Dongdong Wang Ruilin Zheng Zhongyue Wang Weiyan Yue Zhao Quan Bo Peng Wei Wei 《Journal of the American Ceramic Society》2014,97(9):2909-2914
A kind of novel CaF2:Nd microcrystal‐glass composites with high transmittance and long fluorescence lifetime were prepared by a two‐step melt‐quenching technique. Based on Mie theory, a theoretical estimate of the scattering losses was suggested for the microcrystal‐glass composites. By matching dispersion curve of the glass matrix and CaF2 microcrystal in the range of UV–Vis‐NIR, the transmittance can reach 83%. The effects of CaF2:Nd microcrystals/glass ratio on structure and optical properties were investigated. The composite sample‐doped 30 wt% CaF2:Nd nano/microcrystals exhibits long fluorescence lifetime of 518 μs at 1051 nm. 相似文献
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地源热泵系统所利用的热源主要位于地层浅部。它的存在具有普遍性的同时又具有隐蔽性和复杂性,从而决定了地源热泵系统进行工程勘察的必要性,本文从浅层地热能的赋存特征入手阐述工程勘察的必要性,并就工程勘察的程序及注意事项等问题进行了讨论,以希望有关勘察部门在进行地源热泵系统勘察和施工中有所借鉴。 相似文献
9.
针对嵌入式终端设备程序升级困难的问题,设计了一种基于STM32的远程升级方案.该方案系统深入地研究了Ymodem协议的通信流程,以及基于STM32的在应用编程(IAP)的技术原理和关键技术的实现,关键技术包括程序起始位置和中断向量表设置、APP程序区flash擦除、APP程序写入flash、IAP跳转到APP程序等4个部分,利用RS232标准串口实现了上位机与嵌入式终端设备之间基于Ymodem协议的通信,即嵌入式终端设备的远程在线即时更新功能,实际应用表明,该方案具有良好的应用价值和推广价值. 相似文献
10.
Dongyang Jiang Jing Ge Qinyuan Liao Junfan Ma Yang Liu Jing Huang Chong Wang Weiyan Xu Jie Zheng Wenwei Shao Gregory Lee Xiaoyan Qiu 《International journal of molecular sciences》2015,16(2):2574-2590
The innate immune system of the skin is thought to depend largely on a multi-layered mechanical barrier supplemented by epidermis-derived antimicrobial peptides. To date, there are no reports of antimicrobial antibody secretion by the epidermis. In this study, we report the expression of functional immunoglobulin G (IgG) and immunoglobulin A (IgA), previously thought to be only produced by B cells, in normal human epidermal cells and the human keratinocyte line HaCaT. While B cells express a fully diverse Ig, epidermal cell-expressed IgG or IgA showed one or two conservative VHDJH rearrangements in each individual. These unique VDJ rearrangements in epidermal cells were found neither in the B cell-derived Ig VDJ databases published by others nor in our positive controls. IgG and IgA from epidermal cells of the same individual had different VDJ rearrangement patterns. IgG was found primarily in prickle cells, and IgA was mainly detected in basal cells. Both epidermal cell-derived IgG and IgA showed potential antibody activity by binding pathogens like Staphylococcus aureus, the most common pathogenic skin bacteria, but the microbial-binding profile was different. Our data indicates that normal human epidermal cells spontaneously express IgG and IgA, and we speculate that these Igs participate in skin innate immunity. 相似文献