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861.
微/纳多孔金属材料具有高比表面积等优点,在电化学等领域广受关注.本工作通过动态氢气泡模板法,在镀金玻璃碳电极(Aupla/GCE)上电沉积三维蜂窝状多孔纳米AuPtCu (3DHPN-AuPtCu)复合材料,再阳极溶出Cu,制备了3DHPN-AuPtCu/Aupla/GCE.采用循环伏安法(CV)、金相显微镜、扫描电子显微镜、能量色散谱和电感耦合等离子体-原子发射光谱等手段表征了相关修饰电极.所制3DHPN-AuPtCu/Aupla/GCE在含0.2 mol/L HCOOH的0.5 mol/L H2SO4水溶液中,电催化氧化甲酸的峰电流密度为12.5 mA·cmPt-2(CV,-0.3~1.0 V,50 mV/s),优于有关对照电极和很多已报道的Pt复合物修饰电极,表明通过这种动态氢气泡/牺牲铜双模板法可制备出电催化性能优异的金属蜂窝结构. 相似文献
862.
通过连接不同糖片段的三氯乙酰亚胺酯衍生物、甲基衍生物、对甲基苯硫酚衍生物等合成了4个常春藤皂苷元衍生物(4~7,其中6和7为新化合物),其结构经1H NMR和 13C NMR表征。采用MTT法检测了化合物对人结肠癌细胞COLO205的抑制活性。结果表明:4和5对COLO205细胞有部分抑制作用,与浓度正相关;6对COLO205只在高浓度(1.00×10-4mmol/L)有较好抑制作用(98.36±0.43%); 7只在中等浓度(1.00×10-5 mmol/L)对COLO205有微弱抑制作用(2.75±1.22%)。
相似文献
863.
分子筛催化甲醇制烯烃反应(MTO)是典型的扩散主导反应过程,运用频率响应技术系统研究了几种典型产物分子(乙烯/乙烷、丙烯/丙烷、苯)在HZSM-5分子筛上的扩散行为。结果表明,频率响应法成功辨析了不同产物分子的传质规律,证实C2和C3烃分子在HZSM-5微孔孔道内具有相近的扩散速率,但由于受晶体表面阻碍效应影响不同,乙烷分子可自由进出HZSM-5分子筛孔道,而丙烷分子则受到较显著的微孔孔道扩散限制。另外,苯分子的扩散速率显著小于C2和C3分子,且苯分子受晶体表面阻抗效应的影响较小。本研究结果可用于解释HZSM-5分子筛在MTO反应中产物选择性的特点及表面结焦原因,进而从传质角度为高活性、选择性以及稳定性的高效甲醇转化制烃催化剂的定向开发提供理论指导。 相似文献
864.
Cetao Hu Sixuan Zhang Mingliang Wu Xingyu Chen Jingwen Xu Hao Shen Dr. Huan Wang Dr. Di Wu Prof. Jianlong Xia 《化学:亚洲杂志》2021,16(22):3767-3773
Perylene diimide (PDI) is one of the most intensively studied building blocks for the construction of non-fullerene acceptors (NFAs). In this contribution, based on combination of the direct and indirect linkage manners of PDI units at the bay position, a propeller-shaped PDI hexamer T-DPDI was designed and synthesized. The singly bonded PDI dimer DPDI and the benzene ring cored PDI trimer TPDI were synthesized for comparison. The photovoltaic performances of these three PDI derivatives were investigated using the commercially available PTB7-Th as electron donor. A best power conversion efficiency (PCE) of 6.58% was obtained for T-DPDI based organic solar cells (OSCs), which is higher than those of DPDI and TPDI based ones. The superior photovoltaic performance of T-DPDI can be ascribed to its stronger absorption and more favorable morphology. This study presents an interesting example of improving the photovoltaic performances of PDI based NFAs by hybridizing the direct and indirect linkage manners. 相似文献
865.
Hanfeng Hou Ying Jin Huan Wei Wenliang Ji Yifei Xue Prof. Jingbo Hu Prof. Meining Zhang Prof. Ying Jiang Prof. Lanqun Mao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(43):19158-19162
The selective sensing of neurochemicals is essential for understanding the chemical basis of brain function and pathology. Interfacing the excellent recognition features of aptamers with in vivo compatible carbon fiber microelectrode (CFE)-based electroanalytical systems offers a plausible means to achieve this end. However, this is challenging in terms of coupling chemistry, stability, and versatility. Here, we present a new interfacial functionalization strategy based on the assembly of aptamer cholesterol amphiphiles (aptCAs) on the alkyl chain-functionalized CFE. The noncovalent cholesterol-alkyl chain interactions effectively immobilize aptamers onto the CFE surface, allowing the generation of a highly selective system for probing neurochemical dynamics in living systems and opening up a vast array of new opportunities for designing in vivo sensors for exploring brain chemistry. 相似文献
866.
Metal–organic frameworks (MOFs) have attracted great attention owing to their controllable morphologies, adjustable aperture, and large specific surface areas. Here, a typical V-MOF (MIL-47) product is successfully synthesized via a one-step hydrothermal method, which is explored to have a one-dimensional layered nanorod-like framework. From a microcosmic point of view, such a V-MOF product is equipped with a rhomboid structure with a large number of empty channels, which is beneficial for guest ions freely inserting in and extracting from the structure. Hence, the V-MOF product is utilized as the cathode material for the aqueous MOF-Zn battery, which exhibits a high initial specific capacity of 320 mA h/g at 0.1 A/g, and a desirable rate capability and cycling performance. 相似文献
868.
Qin Wang Zhiying Wang Yue Zhao Fumin Li Ling Xu Xiaoming Wang Huan Jiao Yu Chen 《化学:亚洲杂志》2020,15(10):1590-1597
Fabricating highly efficient electrocatalysts for electrochemical hydrogen generation is a top priority to relief the global energy crisis and environmental contamination. Herein, a rational synthetic strategy is developed for constructing well‐defined FeP?CoMoP hierarchical nanostructures (HNSs). In general terms, the self‐supported Co nanorods (NRs) are grown on conductive carbon cloth and directly serve as a self‐sacrificing template. After solvothermal treatment, Co NRs are converted into well‐ordered Co?Mo nanotubes (NTs). Subsequently, the small‐sized Fe oxyhydroxide nanorods arrays are hydrothermally grown on the surface of Co?Mo NTs to form Fe?Co?Mo HNSs, which are then converted into FeP?CoMoP HNSs through a facile phosphorization treatment. FeP?CoMoP HNSs display high activity for hydrogen evolution reaction (HER) with an ultralow cathodic overpotential of 33 mV at 10 mA cm?2 and a Tafel slope of 51 mV dec?1. Moreover, FeP?CoMoP HNSs also possess an excellent electrochemical durability in alkaline media. First‐principles density functional theory (DFT) calculations demonstrate that the remarkable HER activitiy of FeP?CoMoP HNSs originates from the synergistic effect between FeP and CoMoP. 相似文献
869.
对聚变堆中心螺管(CS)线圈中,铠装电缆导体(CICC)中的SS316LN 不锈钢铠甲在运行状态下的断裂性能进行了测试分析。结果显示SS316LN 疲劳裂纹扩展性能较稳定,断裂韧性在经历冷变形与时效热处理后出现了大幅度衰减。此结果为未来核聚变堆超导线圈的设计与性能分析提供了数据参考。 相似文献
870.
An actual ecological predator-prey system often undergoes random environmental mutations owing to the impact of natural disasters and man-made destruction, which may destroy the balance between the species. In this paper,the stochastic dynamics of the nonlinear predator-prey system considering random environmental mutations is investigated, and a feedback control strategy is proposed to reshape the response of the predator-prey system against random abrupt environmental mutations. A delayed Markov jump system(MJS) is established to model such a predator-prey system. A novel first integral is constructed which leads to better approximation solutions of the ecosystem. Then, by applying the stochastic averaging method based on this novel first integral, the stochastic response of the predator-prey system is investigated, and an analytical feedback control is designed to reshape the response of the ecosystem from the disturbed state back to the undisturbed one.Numerical simulations finally illustrate the accuracy and effectiveness of the proposed procedure. 相似文献