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101.
A simple, rapid and sensitive synchronous fluorescence method was developed for the determination of ciprofloxacin (CPFX) in the pharmaceutical formulation and human serum. The results show that when Y3+ is added into the CPFX solution, the characteristic fluorescence of Y3+ is not emitted whereas the fluorescence intensity of CPFX is significantly enhanced. The synchronous fluorescence technology is employed in this method to directly determine trace amount of CPFX in human serum. A linear relationship between the fluorescence intensity and the CPFX concentration is obtained in the range of 1.0×10−9 ∼5.0×10−6 mol L−1. The limit of detection (LOD) of this method attains as low as 2.0×10−10 mol L−1 (S/N=3). The selectivity of this method is also very good. Common metal ions, rare-earth ions and some pharmaceuticals, which are usually used together with CPFX in the clinic, do not interfere with the determination of CPFX under general conditions.  相似文献   
102.
同步荧光光谱分析法在海面溢油鉴别中的应用研究   总被引:1,自引:0,他引:1  
为了实现海面溢油快速筛选和鉴别,文章提出了应用同步荧光光谱技术结合系统聚类分析方法鉴别海面溢油的方法,并应用于不同原油样品及风化油样的分析。结果表明,选择波长差为25nm,采用300~500nm范围内数据进行聚类分析,可以将原油样品和风化样品完全区分开,不同海区、不同采集时间的原油样品可大致分开。作为溢油鉴别的一种辅助方法,同步荧光光谱分析法能够对可疑油源及溢油样品实现初步筛选。  相似文献   
103.
Organic materials with long-lived, color-tunable phosphorescence are potentially useful for optical recording, anti-counterfeiting, and bioimaging. Herein, we develop a series of novel host–guest organic phosphors allowing dynamic color tuning from the cyan (502 nm) to orange red (608 nm). Guest materials are employed to tune the phosphorescent color, while the host materials interact with the guest to activate the phosphorescence emission. These organic phosphors have an ultra-long lifetime of 0.7 s and a maximum phosphorescence efficiency of 18.2 %. Although color-tunable inks have already been developed using visible dyes, solution-processed security inks that are temperature dependent and display time-resolved printed images are unprecedented. This strategy can provide a crucial step towards the next-generation of security technologies for information handling.  相似文献   
104.
Herein, norbornyl (NB), a bulky annular nonconjugated spacer, is melded into π systems to construct two groups of ladder-type room-temperature phosphorescence (RTP) luminogens. The effect of the NB on π-π interactions, packing modes and RTP performance is explored systematically. The experimental and computational results demonstrate the versatility of NB in reducing π-π distances and synergistically intensifying the intermolecular interactions, which not only induces intersystem crossing from S1 to Tn but also diminishes the nonradiative decay of triplet excitons. Impressively, 1800-fold phosphorescence lifetime enhancement is achieved in comparison with the reference compounds without NB. The molecular packing and RTP performance can be further modulated by the length of the backbones and terminal end-groups. It is quite peculiar that NB-annulated phthalic acid exhibits reversible photochromism in the solid state, likely due to the formation of persistent radical pairs. Our study paves an ingenious avenue towards enhancing intermolecular interactions and provides significant implications for a better comprehensive understanding of the origin of their RTP and the inherent photophysical mechanism.  相似文献   
105.
同步荧光—高效液相色谱联用法分析多环芳烃同分异构体   总被引:1,自引:0,他引:1  
曹学丽  胡学华 《分析化学》1994,22(7):664-667
本文以高效液相色谱作为预分离手段,采用步荧光法对两组环芳烃异构体;屈和苯并(a)蒽,苯并(k)荧蒽和北进行了分析研究,结果表明,选择适当的Δλ,可以使色谱法难以分离的两组异构体达到同时测定,该方法具有简单,快速,灵敏等优点,本文此方法应用于海洋沉积物样品的研究,也取得了很的效果。  相似文献   
106.
Total luminescence and synchronous fluorescence spectroscopies were tested as regards their ability to differentiate edible from lampante virgin olive oils. Total luminescence spectra were recorded by measuring the emission spectra in the range 350-720 nm at excitation wavelengths from 320 to 535 nm. The synchronous fluorescence spectra of 41 edible and 32 lampante virgin olive oils were acquired by synchronous scanning the excitation and emission monochromator maintained at an offset value of 80 nm. Classification of virgin olive oils based on their synchronous fluorescence spectra was performed by hierarchical cluster analysis and principal component analysis using the spectral range of 429-545 nm. Principal component analysis provided better discrimination between the two classes, without any classification error, while hierarchical cluster analysis allowed 97.3% correct classification. These results indicate the capability of fluorescence techniques to differentiate virgin olive oils according to their quality.  相似文献   
107.
通过数学推导和实验验证,提出了同步荧光光谱谱带半峰宽度的经验计算式的修正式和导数光谱峰高的计算式,从理论上说明了同步-导数荧光测定的灵敏度比相应的常规荧光测定、同步荧光测定和导数荧光测定等方法的灵敏度高。  相似文献   
108.
A new method for the determination of trace calcium by solid substrate-room temperature phosphorimetry is established. It is based on the fact that chromeazurols azurol S-phenanthroline-NaCMC (CAS-phen-NaCMC) system can emit strong and stable room temperature phosphorescence (RTF) on the solid substrate in the filter paper. Ca2 and phenanthroline can form complex ion Ca(phen)32 , which will form complex [Ca(phen)3(CAS)2] with CAS. In the result, the number of CAS molecules in each spot increased, causing sharp increase of the RTP signal of the CAS-phen-NaCMC system.  相似文献   
109.
锐钛矿型多孔TiO2薄膜的溶解法制备及性能表征   总被引:2,自引:0,他引:2  
在具有锐钛矿晶粒的TiO2溶胶中加入苯丙乳液粒子,使用该混合液浸渍提拉涂膜,然后利用甲苯将薄膜中的苯丙乳液粒子溶解去除,并通过重复涂膜,在室温下获得了具有良好多孔性的锐钛矿型TiO2薄膜。考察了多孔薄膜的表面形貌、光学性能、吸附性能和光催化性能。结果表明:随薄膜涂膜次数的增加,TiO2多孔薄膜的吸光度增大,透光率减小,光吸收边波长向长波方向移动。罗丹明B在TiO2多孔薄膜上的吸附量随涂膜次数的增加先升高,后降低;多次涂膜会在薄膜中产生半封闭的孔洞,经过长时间的毛细渗透等作用能进一步增加薄膜对罗丹明B的吸附。TiO2多孔薄膜通过吸附+光催化氧化的模式快速分解罗丹明B,其活性主要受到薄膜在光催化反应初期的吸附能力的影响。此外,TiO2的负载量、光的利用效率、以及光生电荷迁移及其分离等也是影响薄膜光催化活性的因素。  相似文献   
110.
研究了一种测定人尿中异黄蝶呤的同步荧光分析方法.在KH2PO4-NaOH缓冲溶液中(pH 7.8),波长差(Δλ)为65 nm的条件下进行同步荧光扫描,可有效排除尿液中其它物质对异黄蝶呤测定的干扰.异黄蝶呤的质量浓度在0~1.4 μg/mL范围内与荧光强度呈良好的线性关系.线性方程为Ⅰ=4105.3ρ 59.696, 相关系数r=0.9997.异黄蝶呤添加到健康人和胃癌病人尿样中的平均回收率分别在102.9%~108.4%及85.6%~95.6%之间,其相对标准偏差(RSD)分别为0.37%~1.2%及1.0%~2.2%.方法已应用于人尿中异黄蝶呤的测定.  相似文献   
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