共查询到20条相似文献,搜索用时 15 毫秒
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为了开发一系列能够在纯水介质中使用的荧光凝胶材料,以TbCl_3·6H_2O和乙酰丙酮(ACAC)为初始原料合成了铽配合物Tb(ACAC)_3·2H_2O,并对其结构进行了表征。然后将铽配合物Tb(ACAC)_3·2H_2O以不同的质量分数引入到PVA基质中,在交联剂硼酸的作用下形成荧光凝胶。利用FTIR、PL、DSC、TGA等对其结构、发光性能及其热性能进行了研究。FTIR结果表明,铽配合物成功地掺杂到了PVA凝胶体系中。荧光发射光谱表明,所有铽配合物的PVA荧光凝胶都具有很好的荧光性能,更重要的是掺杂了3%、5%、7%铽配合物的PVA荧光凝胶位于545 nm处的特征发射峰的发射强度相比于小分子铽配合物Tb(ACAC)_3·2H_2O的发射强度更高,分别是其2.15、3.27和5.65倍。表明PVA基质对铽配合物具有较好的敏化作用。此外,DSC和TGA研究结果表明,铽配合物的引入使得PVA凝胶的热稳定性略有下降,但影响不大。 相似文献
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Bhupendra S. Rane Muddassar A. Kazi Sandeep M. Bagul Deepak P. Shelar Raghunath B. Toche Madhukar N. Jachak 《Journal of fluorescence》2010,20(1):415-420
A convenient route was successfully developed for the synthesis of novel heterocycles such as spiro-oxazino-quinoline derivatives from 2-aminoquinoline-3-carbonitrile (4) in good yield. The Spiro-quinoline derivatives (6, 8 and 10) were synthesized and further studied for their photophysical properties. Semiempirical molecular orbital calculation (PM3/PM6 for structure) proves to be a suitable tool for the prediction of absorption and fluorescence properties of these compounds. 相似文献
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Novel coumarin derivatives have been synthesized by the classical Knoevenagel condensation of 4-hydroxy-9-methyl-9H-carbazole-3-carbaldehyde with active methylene compounds and characterized. Effect of solvent polarity on the photophysical properties, absorption and emission has been studied. The photophysical properties of the synthesized coumarins have been compared with some of the established analogous coumarin derivatives. Investigation of the structural parameters and understanding photophysical properties of the synthesized coumarin derivatives were carried out using Density Functional Theory (DFT) and Time Dependant Density Functional Theory (TDDFT) computations. The experimental values were correlated with the theoretical derived results. The ratio of the excited state and the ground state dipole moments was calculated by using solvatochromic and solvatofluoric data and compared with the values obtained from DFT and TDDFT computations. 相似文献
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Sebile Işık Büyükekşi Sevinc Zehra Topal Devrim Atilla 《Journal of fluorescence》2017,27(4):1257-1266
Herein, novel silicon (IV) phthalocyanines peripherally substituted by triethylene glycol groups and bearing axial hydroxyl groups were synthesized and fully characterized by using different analyses techniques. The photophysical and photochemical properties of octa (2a) and tetra (2b) derivatives were investigated in DMF and DMSO. The effect of octa or tetra substitution on fluorescence quantum yield, singlet oxygen generation and photodegradation were examined, and the differences were evaluated regarding their potential efficiency in photodynamic therapy (PDT). Their pH-responses were investigated to determine the influence of protonation of azomethine nitrogen atoms on singlet oxygen generation efficiencies. Dramatic optical changes were observed by protonation of azomethine bridges of 2a and 2b. They exhibited signal decrease from pH 4.0 to 1.0 for 2a (pKa = 2.6) and pH 3.0 to 1.0 for 2b (pKa = 1.8). Besides, the compounds exhibited no aggregation tendency, moderate fluorescence quantum yield, solubility in common organic solvents, high singlet oxygen quantum yield and high photostability in DMF and in DMSO, these favorable properties making them good candidates as photosensitizer for PDT. 相似文献
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Qingwei Jiang Jing Xu Tianduo Li Congde Qiao Yulong Li 《Journal of Macromolecular Science: Physics》2014,53(1):133-141
Cationic proteins with tunable chemical and physical properties were prepared from 2,3-epoxypropyl trimethyl ammonium chloride (EPTAC) and gelatin. Measurement of grafting density indicated that the molar ratio of EPTAC/amine groups (NH2) in the gelatin chains played a key role in determining the compound's structure. Fourier transform infrared (FTIR) and 13C NMR results showed that the –NH2 functional groups of gelatin were totally consumed when the molar ratio of EPTAC/NH2 was increased to 2.5:1. Hydroxyl (?OH) functional groups of gelatin were also depleted upon further increasing the molar ratio of EPTAC/NH2. Antibacterial activity and thermal properties of the product polymers changed with the modification of the polymers’ structure. 相似文献
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Journal of Fluorescence - Phenanthroimidazole-thiadiazole hybrid derivatives, which are new heterocyclic compounds with fluorescence properties, were synthesized by designing a two-step reaction... 相似文献
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以魔芋葡甘聚糖为载体,以硝酸铈铵作引发剂,用甲基丙烯酰氧乙基-十四烷基-二甲基溴化铵为活性单体进行接枝共聚反应制备季铵盐型魔芋葡甘聚糖衍生物。用核磁共振,红外光谱,DSC和激光粒度Zeta电位仪对接枝产物进行了表征和测定,用悬菌定量实验研究了其抗菌性能。结果表明:(1)甲基丙烯酰氧乙基-十四烷基-二甲基溴化铵通过其双键接枝到魔芋葡甘聚糖表面,接枝率随着季铵盐单体的用量增加而提高;(2)魔芋葡甘聚糖的零电位在pH 4.5,魔芋葡甘聚糖季铵盐衍生物的零电位在pH 9.9,季铵基的引入使其零电位发生了较大的位移;(3)所制备的魔芋葡甘聚糖季铵盐衍生物对大肠杆菌、金黄色葡萄球菌以及白色念珠菌在振荡作用15 min后,平均杀菌率分别为99.99%,99.99%和98.13%。 相似文献
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季铵盐型纳米气相二氧化硅衍生物的合成、表征及生物学活性 总被引:1,自引:0,他引:1
以纳米气相SiO2为载体,以γ- 氯丙基三甲氧基硅烷作偶联剂,用N,N-二甲基十四烷基叔胺进行了季铵化反应制备季铵盐型纳米气相二氧化硅衍生物。用红外光谱,DSC和激光粒度Zeta电位仪对纳米气相二氧化硅季铵盐衍生物进行了表征和测定,用悬菌定量实验(Suspension quantitative test)研究了其抗菌性能。结果表明:(1) γ- 氯丙基三甲氧基硅烷通过与纳米气相二氧化硅表面羟基的反应键合到二氧化硅表面,随着γ-氯丙基三甲氧基硅烷的用量增加,纳米气相二氧化硅表面羟基被取代程度也增加;(2)纳米气相二氧化硅的零电位在pH 4.8,纳米气相二氧化硅季铵盐衍生物的零电位在pH 10.5,季铵盐的引入使其零电位发生了较大的位移;(3)所制备的纳米气相二氧化硅季铵盐衍生物对大肠杆菌、金黄色葡萄球菌以及白色念珠菌在振荡作用15 min后,平均抑菌率分别为99.99%,99.99%和94.12%。 相似文献
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几种饱和脂肪酸及其盐的拉曼光谱研究 总被引:3,自引:2,他引:3
饱和脂肪酸及其盐在自然界中广泛存在,它们也是重要的化工原料。但是有关此类物质拉曼光谱特征的研究尚属少见。为了进一步了解它们的拉曼光谱特征,对乙酸、硬脂酸及乙酸钙、乙酸镁、硬脂酸钙、硬脂酸镁进行了拉曼光谱研究。从指认这6种物质拉曼光谱的特征峰拉曼位移出发,对它们的相应谱峰进行比对与分析,探讨了阳离子的引入对饱和脂肪酸及其盐的拉曼光谱的影响,找出了它们拉曼光谱的差异。比较不同阳离子形成的饱和脂肪酸盐的特征峰拉曼位移的差别,从折合质量和核外电子构型角度解释了造成差异的原因。同时发现了长碳链可以减弱不同阳离子对饱和脂肪酸盐拉曼光谱造成的影响。 相似文献
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Optics and Spectroscopy - Optical characteristics of nitrate and nitrite salts and their aqueous solutions are studied to demonstrate the application of direct spectrophotometric methods for... 相似文献
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Oksana Aganova Leisan Galiullina Albert Aganov Yurii Shtyrlin Mikhail Pugachev Nikita Shtyrlin Vladimir Klochkov 《Applied magnetic resonance》2014,45(7):653-665
A number of quaternary phosphonium salts on the basis of pyridoxine derivatives were investigated by nuclear magnetic resonance (NMR) spectroscopy methods. Conformational exchange processes for each compound in solution were studied using dynamic NMR experiments. Energy barriers of the conformational transitions were determined. 相似文献
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Synthesis of Novel Carbazole based Styryl: Rational Approach for Photophysical Properties and TD-DFT
Nagaiyan Sekar Prashant G. Umape Shantaram Kothavale Mininath Deshmukh 《Journal of fluorescence》2014,24(5):1457-1472
The synthesis and solvatochromic behavior of four novel carbazole based fluorescent styryl dyes were explained. In chlorinated solvents such as DCM and chloroform, these dyes show bathochromic shift in their absorption as well as emission. The styryl dyes 6b and 6c show solid state yellow fluorescence. DFT and TD-DFT computations were performed to study structural, molecular, electronic and photophysical properties of these dyes. The computed absorption and emission wavelength values are found to be in good agreement with the experimental results. The photophysical properties of these 1-styryl carbazole dyes are also compared with the recently reported 3-styrl carbazole dyes. The unique behavior of dye 6d is well explained by its optimized geometry found in the excited state. Ratio of ground to excited state dipole moment of the synthesized novel styryl compounds were calculated by Bakhshiev and Bilot-Kawski correlations. 相似文献