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1.
5-amino-l,10-phenanthroline (5-AP), as a tautomeric heterocyclic aromatic chelating fluorophore (THACF), can sense Zn^2+ selectively by shifting emission from 495 to 564 nm upon Zn^2+ addition in ethanol. The ratiometric fluorescent sensing behavior has been correlated to the tautomerization of 5-AP affected by solvents and metal chelation. The strategy using THACF as ratiometric fluorescent sensor for Zn^2+ not only simplifies the synthetic procedure but also gives a promising alternative for Zn^2+ ratiometric fluorescent sensor design. 相似文献
2.
阿尔茨海默症(Alzheimer’s disease, AD)是一种神经退行性疾病,严重影响老年人的生活质量,目前治疗AD的药物主要是胆碱酯酶抑制剂,如多奈哌齐、卡巴拉汀等.本文基于多奈哌齐结构,设计合成了一系列新的萘酰亚胺衍生物并进行了活性评价.结果表明,所合成的化合物均对乙酰胆碱酯酶(AChE)有选择性抑制,其中2-((1-(3-甲氧基苄基)哌啶-4-基)甲基)-1H-苯并异喹啉-1,3(2H)-二酮(4k)的抑制活性最强,IC50值为4.43μmol·L-1,优于对照药物卡巴拉汀.酶动力学及分子对接表明4k能够同时作用于ACh E的催化活性位点和外周结合位点,并且4k对SH-SY5Y和PC12细胞毒性较低.此外,这些化合物均显示出典型的聚集诱导发光(AIE)性质,可能与萘酰亚胺分子内旋转受阻机制有关. 相似文献
3.
设计合成了一个新的双1,8-萘酰亚胺衍生物(Bis-Nph), 并通过核磁共振波谱和高分辨质谱鉴定了其结构. Bis-Nph呈现出典型的分子内电荷转移(ICT)和聚集诱导增强发射(AIEE). 该化合物可以作为荧光探针检测水溶液中的苦味酸(2,4,6-三硝基苯酚, TNP), 检出限为5.8×10-7 mol/L. 作用机制为TNP的质子转移到Bis-Nph, 有效地阻断了其ICT发射, 使荧光发生显著猝灭. 另外, Bis-Nph的细胞毒性较低, 可做成试纸进行TNP的快速检测. 相似文献
4.
以芳香氮芥N,N-二(2-氯乙基)-1,4-苯二胺为药效基团,不同链长的萜醇和饱和醇为载体,通过氨基甲酸酯的联接方式,设计合成了6个芳香氮芥衍生物,收率在66%~90%之间,所有目标化合物的结构均经元素分析、1H NMR、13C NMR和MS测试技术确证.对K562(白血病细胞),B16(黑色素瘤)和CHO(中国仓鼠卵巢细胞)3种细胞模型进行了体外抗肿瘤活性测试,结果表明,部分化合物的活性较N,N-二(2-氯乙基)-1,4-苯二胺有明显提高,并在一定浓度范围内与商品药物美法仑(Melphalan)相当,其中法尼基修饰的化合物6e在浓度为0.1~10 μmol/L范围内,对B16细胞的体外抑制率明显优于美法仑. 相似文献
5.
变色材料广泛应用于航空航天、能源化工、日用食品、国防及科学研究等诸多领域。紫精化合物(N-取代的-4,4’-联吡啶季铵盐,V)能在外界光、电、热等激发下表现出多样的变色性质,是一类重要的变色材料。本文将紫精变色材料的科学前沿成果引入本科实验教学,创新设计了一个面向本科低年级学生开设的大学化学基础实验。该实验以激发学生的好奇心与探索欲,培养学生对化学的学习兴趣,开阔学生的视野,提高学生对化学的认知为目的,合成了邻羟基苯乙酮取代基紫精,研究了它的溶剂化显色、热致变色及对NH3的可逆显色反应。实验的特点是反应原料简单易得、合成方法简便、反应时间短、产率高、实验操作安全可靠、变色现象均可以不借助仪器而裸眼直接观察、变色过程快速且灵敏。这些优势为实验项目的应用与推广提供了极大的便利。 相似文献
6.
We report on stacking fault (SF) detection in free-standing cubic-SiC epilayer by the Raman measurements. The epilayer with enhanced SFs is heteroepitaxially grown by low pressure chemical vapour deposition on a Si(100) substrate and is released in KOH solution by micromechanical manufacture, on which the Raman measurements are performed in a back scattering geometry. The TO line of the Raman spectra is considerably broadened and distorted. We discuss the influence of SFs on the intensity profiles of TO mode by comparing our experimental data with the simulated results based on the Raman bond polarizability (BP) model in the framework of linearchain concept. Cood agreement with respect to the linewidth and disorder-induced peak shift is found by assuming the mean distance of the SFs to be 11 A in the BP model. 相似文献
7.
芳胺氮芥衍生物的合成与生理活性研究 总被引:1,自引:0,他引:1
以芳香氮芥N,N-二(2-氯乙基)-1,4-苯二胺为药效基团,4位取代的苯胺和α-萘胺为载体,通过尿素的连接方式,合成了5个芳胺类氮芥衍生物,所有化合物的结构经元素分析、1HNMR、13CNMR和MS测试确证。对K562(白血病细胞),B16(黑色素瘤)和CHO(中国仓鼠卵巢癌细胞)三种细胞模型进行了体外抗肿瘤活性测试,结果表明部分化合物的活性较N,N-二(2-氯乙基)-1,4-苯二胺有明显提高,其中化合物5e在一定的浓度范围内与商品药物美法仑相当。 相似文献
8.
<正>Epitaxial growth of semiconductor films in multiple-wafer mode is under vigorous development in order to improve yield output to meet the industry increasing demands.Here we report on results of the heteroepitaxial growth of multi-wafer 3C-SiC films on Si(100) substrates by employing a home-made horizontal hot wall low pressure chemical vapour deposition(HWLPCVD) system which was designed to be have a high-throughput,multi-wafer(3×2-inch) capacity. 3C-SiC film properties of the intra-wafer and the wafer-to-wafer including crystalline morphologies,structures and electronics are characterized systematically.The undoped and the moderate NH3 doped n-type 3C-SiC films with specular surface are grown in the HWLPCVD,thereafter uniformities of intra-wafer thickness and sheet resistance of the 3C-SiC films are obtained to be 6%~7%and 6.7%~8%,respectively,and within a run,the deviations of wafer-to-wafer thickness and sheet resistance are less than 1%and 0.8%,respectively. 相似文献
9.
Growth of a Novel Periodic Structure of SiC/AIN Multilayers by Low Pressure Chemical Vapour Deposition
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A novel lO-period SiC/A1N multilayered structure with a SiC cap layer is prepared by low pressure chemical vapour deposition (LPCVD). The structure with total film thickness of about 1.45~m is deposited on a Si (111) substrate and shows good surface morphology with a smaller rms surface roughness of f.3 nm. According to the secondary ion mass spectroscopy results, good interface of the 10 period SiC/A1N structure and periodic changes of depth profiles of C, Si, A1, N components are obtained by controlling the growth procedure. The structure exhibits the peak reflectivity close to 30% near the wavelength of 322 nm. To the best of our knowledge, this is the first report of growth of the SiC/AIN periodic structure using the home-made LPCVD system. 相似文献
10.
Quantitative and sensitive detection of prohibited fish drugs by surface-enhanced Raman scattering
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Rapid and simple detections of two kinds of prohibited fish drugs, crystal violet(CV) and malachite green(MG),were accomplished by surface-enhanced Raman scattering(SERS). Based on the optimized Au/cicada wing, the detectable concentration of CV/MG can reach 10~(-7) M, and the linear logarithmic quantitative relationship curves between log I and log C allows for the determination of the unknown concentration of CV/MG solution. The detection of these two analytes in real environment was also achieved, demonstrating the application potential of SERS in the fast screening of the prohibited fish drugs, which is of great benefit for food safety and environmental monitoring. 相似文献