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41.
Although great progress has been made in the advancement of nanozymes, most of the studies focus on mimicking peroxidase, oxidase, and catalase, while relatively few studies are used to mimic laccase. However, the use of nanomaterials to mimic laccase activity will have great potential in environmental and industrial catalysis. Herein, Cu/CuO-graphene foam with laccase-like activity was designed for the identification of phenolic compounds and the detection of epinephrine. In a typical experiment, the formation mechanism of Cu/CuO-graphene foam was investigated during the pyrolysis process by thermogravimetric-mass spectrometry. As a laccase mimic, Cu/CuO-graphene foam exhibited excellent catalytic activity with a Michaelis-Menten constant and a maximum initial velocity of 0.17 mmol/L and 0.012 mmol∙L-1∙s-1, respectively. Based on this principle, Cu/CuO-graphene foam nanozyme could differentially catalyze phenolic compounds and 4-aminoantipyrine for simultaneous identification of phenolic compounds. Furthermore, a colorimetric sensing platform was fabricated for the quantitative determination of epinephrine, showing linear responses to epinephrine in the range of 3 mg/mL to 20 mg/mL with the detection limit of 0.2 mg/mL. The proposed Cu/CuO-graphene foam nanozyme could be applied for the identification of phenolic compounds and the detection of epinephrine, showing great potential applications for environmental monitoring, biomedical sensing, and food detection fields.  相似文献   
42.
占兴  熊巍  梁国熙 《化学进展》2022,34(11):2503-2516
随着经济的飞速发展,社会对能源的需求日益扩大,对工业废水的无害化处理也提出了更高的要求。光催化燃料电池 (photocatalytic fuel cell, PFC) 在燃料电池中引入半导体光催化材料作为电极,实现了有机污染物高效降解和同步对外产电的双重功能,在废水无害化与资源化利用方面具有潜在的应用价值。半导体光催化电极是PFC系统高效运行的核心组件,增强其可见光响应和光生载流子分离是提高PFC性能的关键策略。反应器结构设计和运行参数优化也有利于改善PFC性能。本文从PFC基本原理和应用入手,综述了PFC在环境污染物资源化处理中的研究进展,并详细阐述了提高PFC的污染控制性能和产电效率的优化手段,为进一步设计高效稳定的PFC系统并实现其在水污染控制和清洁能源生产中的应用提供理论指导。  相似文献   
43.
44.
Journal of Thermal Analysis and Calorimetry - A complete analysis of the thermal process about melamine was presented, in which different methods were applied to determine the characteristic of the...  相似文献   
45.
Ru is an important catalyst in many types of reactions. Specifically, Ru is well known as the best monometallic catalyst for oxidation of carbon monoxide (CO) and has been practically used in residential fuel cell systems. However, Ru is a minor metal, and the supply risk often causes violent fluctuations in the price of Ru. Performance‐improved and cost‐reduced solid‐solution alloy nanoparticles of the Cu‐Ru system for CO oxidation are now presented. Over the whole composition range, all of the CuxRu1?x nanoparticles exhibit significantly enhanced CO oxidation activities, even at 70 at % of inexpensive Cu, compared to Ru nanoparticles. Only 5 at % replacement of Ru with Cu provided much better CO oxidation activity, and the maximum activity was achieved by 20 at % replacement of Ru by Cu. The origin of the high catalytic performance was found as CO site change by Cu substitution, which was investigated using in situ Fourier transform infrared spectra and theoretical calculations.  相似文献   
46.
Wu  Fang  Guo  Xiaoxue  Hao  Gazi  Hu  Yubing  Jiang  Wei 《Journal of Solid State Electrochemistry》2019,23(9):2627-2637
Journal of Solid State Electrochemistry - Developing low-cost and earth-abundant electrocatalysts with high activity for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER)...  相似文献   
47.
Han  Jing  Sun  Youhong  Guo  Wei  Deng  Sunhua  Hou  Chuanbin  Qu  Lili  Li  Qiang 《Journal of Thermal Analysis and Calorimetry》2019,135(4):2287-2296
Journal of Thermal Analysis and Calorimetry - In this study, the non-isothermal pyrolysis method was used to investigate the pyrolysis characteristics of oil shale from four areas: namely Nongan,...  相似文献   
48.
X-ray imaging functionalization of biodegradable polyesters is a great demand and challenge in biomedical applications.In this work,a strategy of in-chain functionalization through the combination of ring opening copolymerization and oxime "Click" postfunctionalization was developed towards X-ray opaque polylactide copolymers.A functionalized cyclic carbonate was first synthesized and used as comonomer of polylactide copolymers,which were subjected to postfunctionalization of oxime "Click" reaction towards iodinated polylactide copolymers.The chemical structure and physical properties of the target products were traced and confirmed.In vitro cytotoxicity evaluation with 3T3-Swiss albino by Alamar blue demonstrated a low cytotoxicity.The X-ray radiopacity was analyzed by Micro-CT and quantified by Hounsfield Units value,which could be tailorable by the feedstock.It is a promising X-ray visible implantable biomaterial in biomedical applications.  相似文献   
49.
李涛  陈瑜  刘伟  张琦  黄西平 《合成化学》2020,28(1):67-77
有机三溴化铵(OATBs)作为溴素的固体形式,具有优良的反应活性和热稳定性,是一类重要的溴化试剂,在有机合成中应用广泛。本文从反应类型、OATBs种类和作用机理等方面,对OATBs参与的溴化反应的研究进展进行了全面分析。通过与溴素对比,指出了该类化合物在芳基的选择性溴化、双键的立体选择性加成和羰基的α-溴代等方面的研究价值。针对研究现状,提出绿色、高效的反应体系是其未来的发展方向。  相似文献   
50.
Pickering乳液以胶体尺寸的固体粒子代替传统表面活性剂作为稳定剂,具有超稳定,生物相容性好以及对环境友好等优点。开关型Pickering乳液可随pH值、CO2/N2浓度、温度、磁场强度及光强度等条件的变化而改变固体乳化剂的表面润湿性,实现在“乳化”与“破乳”之间的快速转换,在非均相催化、乳液聚合等诸多领域有广泛的应用前景。本文全面总结了近年来开关型Pickering乳液的研究进展及其在界面催化系统、液膜处理有机废水、药物的包封与释放等方面的应用。  相似文献   
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