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61.
在三氟化硼乙醚(BFEE)-聚乙二醇(分子量400,PEG400)混合电解质溶液中,1,8-亚乙基萘直接阳极氧化聚合可以获得自支撑聚(1,8-亚乙基萘)膜.单体在三氟化硼乙醚+10%PEG400中的起始氧化电位为0.95 Vversus SCE,远低于单体在0.1 mol.L-1四氟化硼四丁基胺-乙腈溶液中的起始氧化电位(1.38 VversusSCE).同时PEG400的加入可以有效改善单体在三氟化硼乙醚中的溶解性.UV-Vis,FTIR和1H-NMR确定了1,8-亚乙基萘在4,5位聚合,荧光光谱表明固态及可溶聚(1,8-亚乙基萘)膜是蓝色发光材料. 相似文献
62.
《Tetrahedron: Asymmetry》2006,17(18):2649-2653
A series of cyclohexanones substituted at the 4-position with a selection of hydrophobic and hydrophilic groups were used as substrates in the evaluation of six new cyclopentanone monooxygenase (CPMO) mutants. These mutants were obtained through evolutionary modifications in two specific regions of the CPMO’s putative active site. Several mutant enzymes with improved enantioselectivity were identified. Analysis of the results, in terms of a diamond model, illustrates how a family of cyclohexanone substrates may be used to explore putative active sites of Baeyer–Villiger monooxygenases (BVMOs) and to design productive mutations for specific substrates. 相似文献
63.
单分散磁性纳米颗粒的制备及生物高分子在其上的组装 总被引:3,自引:0,他引:3
磁性纳米颗粒因其潜在的生物医学应用价值而成为纳米生物材料领域研究的前沿。本文综述了单分散磁性纳米颗粒的制备方法以及生物高分子在磁性纳米颗粒上的组装的研究进展。 相似文献
64.
Introduction Ionchromatography (IC)hasbeenrecognizedasausefulmethodfortheseparationofinorganicanionsandcationssinceitsintroductionbySmalletal .in 1975 .1AsignificanttrendinthedevelopmentofICmethodissearchforsensitiveanduniversaldetectionmethods .Themaindet… 相似文献
65.
A method based on headspace solid-phase microextraction-gas chromatography-mass spectrometry is proposed for the quality control of multilayer packaging and its manufacturing process. Volatile organic compounds (VOCs) are produced in the manufacturing process of the packaging. They can cause organoleptic problems or modify the properties of the packaging depending on the nature and the amount of the VOCs formed. The quantification using packaging samples with a known VOC concentration for the calibration is proposed in order to reduce the analysis time, and the method is validated using a statistical test. Finally, the method is applied to the determination of odour-responsible compounds in multilayer packaging samples obtained under different extrusion-coating conditions, i.e. type of extruder, type of polymer and extrusion speed. 相似文献
66.
67.
A novel thin-layer amperometric detector (TLAD) based on chemically modified ring-disc electrode and its application for simultaneous measurements of nitric oxide (NO) and nitrite (NO2−) in rat brain were demonstrated in this work. The ring-disc electrode was simultaneously sensitive to nitric oxide (NO) and nitrite (NO2−) by modifying its inner disc with electropolymerized film of cobalt(II) tetraaminophthalocyanine (polyCoTAPc)/Nafion and its outer ring with poly(vinylpyridine) (PVP), respectively. The ring-disc electrode was used to constitute a novel TLAD in radial flow cell for simultaneous measurements of NO and NO2− in rat brain combined with techniques of high performance liquid chromatography (HPLC) and in vivo microdialysis. It was found that the basal concentration of NO in the caudate nucleus of rat brain is lower than 1.0×10−7 mol l−1, NO2− concentration is 5.0×10−7 mol l−1 and NO exists in brain maybe mainly in the form of its decomposed product. 相似文献
68.
Cyanobenzaldehydes (m-,o-,p-) were synthesized by oxidation of corresponding tolunitriles with molecular oxygen,catalyzed by cobalt acetate and sodium bromide. 相似文献
69.
《中国化学快报》2020,31(4):922-930
MXenes have emerged as versatile 2D materials that are already gaining paramount attention in the areas of energy,catalyst,electromagnetic shielding,and sensors.The unique surface chemistry,graphene-like mo rphology,high hydrophilicity,metal-like conductivity with redox capability identifies MXenes,as an ideal material for surface-related applications.This short review summarizes the most recent reports that discuss the potential application of MXenes and their hybrids as a transducer material for advanced sensors.Based on the nature of transducing signals,the discussion is categorized into three sections,which include electrochemical(bio) sensors,gas sensors,and finally,electro-chemiluminescence fluorescent sensors.The review provides a concise summary of all the analytical merits obtained subsequent to the use of MXenes,followed by endeavors that have been made to accentuate the future perspective of MXenes in sensor devices. 相似文献
70.