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51.
以光化学荧光衍生化法测定苋菜红(AM)和直接耐晒嫩黄5GL(DY)2种偶氮色素,研究了同时测定这2种色素混合物的光化学速差动力学荧光分析的原理和方法。AM和DY的浓度分别在0~220ng/mL和0~120ng/mL范围内呈良好的线性关系,相关系数皆为0.999,检出限为0.64ng/mLAM和0.045ng/mLDY。相对标准偏差分别为1.6%(n=8)和1.8%(n=7)。该法用于人工合成混合样品的测定效果良好。 相似文献
52.
Yusheng Fu Haiyan Tan Xiujian Wu Xiaohe Wu Yongzheng Yang Yanling Gao Ruowei Liu Min Qi Xiaoyun Chen Yaochao Ning Weidong Sun Nianhuan Chang Junjie Ma Kang Cheng Hongni Yang Qing Li Ping Wang Chaoran Wu Hong Xian Li Wang 《Electrophoresis》2021,42(9-10):1043-1049
Currently, the global healthcare market is increasing at high speed with the impendent global aging issue. Healthcare Industry 4.0 has emerged as an efficient solution towards the aging issue since it was integrated with ubiquitous medical sensors, big health processing platform, high bandwidth, speed technologies, and medical services, etc. It is believed to fulfil the requirement of the tremendously growing health market. The acquisition of medical data acts as the dominant precondition to implement the Healthcare Industry 4.0. In the same way, the widely available smartphone could serve as the best biomedical information collect station. In this study, a smartphone-powered photochemical dongle is demonstrated to precisely estimate blood creatinine from the fingertip blood, which works as a highly compact reflectance spectral analyzer with an enzymatically dry chemical test strip. Comparing with conventional laboratory facility for the evaluation and treatment of chronic kidney disease (CKD), it implemented the platform of point care with agreed accuracy. In order to estimate the efficiency of treatment and recovery of the CKD, the proposed photochemical dongle would provide a flexible and rapid platform for point of care. Furthermore, the proposed measured technology is very promising method for remote CKD management. 相似文献
53.
This article reviews optical manipulation coupled with photochemical/photothermal responses of nanometer sized materials including molecular systems, polymers, and inorganic nanoparticles. After the introduction, section 2 overviews the optical trapping of nanometer sized molecular systems including early-stage studies, such as trapping of polymer chains, micelles, and molecular aggregates in solution at room temperatures. Then, the conformation control of macromolecule assemblies and gels by optical force are introduced, followed by micro-fabrications achieved by combining optical trapping and photochemical reactions. Section 3 summarizes studies on the evaluation of optical force acting on nanometric molecular systems using fluorescence correlation techniques. Approaches to control optical force by using photochemical reactions are show in section 4, where the absorption band of target materials are modified through photochromic reactions, leading to micromechanical motion of small particles synchronizing with the photochemical reactions. Section 5 overviews photothermal effect in optical manipulation such as natural convection, Marangoni convection and thermophoresis, and applications of the thermal effects to develop new methods of micromanipulation achieved by combining optical force and photothermal responses. 相似文献
54.
对二氟沙星在中性水溶液中的光化学性质进行了研究.在pH值为7.17的水溶液中二氟沙星的紫外吸收峰位于273 nm(摩尔消光系数ε=33000 dm3·mol-1·cm-1),323 nm(ε=15500 dm3·mol-1·cm-1),335 nm(ε=15500 dm3·mol-1·cm-1)处.荧光吸收和发射光谱均显示二氟沙星具有pH效应,其pKa(电离平衡常数)测定分别为5.9和9.8.二氟沙星的荧光量子产额较低,在pH=3.00时达到最大值,为0.06.同时对二氟沙星在中性水溶液中的激光光解和脉冲辐解进行详细研究.激光光解研究发现在水溶液中二氟沙星的三重激发态位于620nm,其摩尔消光系数为7900 dm3·mol-1·cm-1.通过能量转移的方法得到其三重激发态的能量为263.5 kJ·mol-1,三重激发态的量子产额为0.21.在激光激发下,二氟沙星进行单光子电离其量子产额为0.02.脉冲辐解研究表明二氟沙星可以与水合电子(e-aq)及羟基自由基(·OH)快速反应,其二级反应动力学常数分别为1.72×1010和1.0×1010dm3·mol-1·s-1.本文对二氟沙星光化学性质的研究有助于确定其光敏毒性的产生机理. 相似文献
55.
A highly efficient environment-friendly photochemical methodology has been developed for the condensation of Meldrum’s acid with aromatic aldehydes in water-ethanol solution sans any catalyst, support or promoter. 相似文献
56.
Virginie AndréAnne Vidal Jean OllivierSylvie Robin David J. Aitken 《Tetrahedron letters》2011,52(12):1253-1255
The (+)-(1R,2S) and (−)-(1S,2R) stereoisomers of 2-(aminomethyl)cyclobutane-1-carboxylic acid have been prepared using a short and efficient strategy, which employs the photochemical [2+2] cycloaddition reaction between ethylene and an unsaturated γ-lactam as the key step. 相似文献
57.
采用“原位反应”的方法,研究了配合物Pt(PMe3)2(CO)2和Pt(diphos)(CO)2(diphos:1,2-二(二特丁基膦)乙烷,即d(t-Bu)Pe,1,2-二(二环己基膦)乙烷,即dCyhPe;1,2-二(二环戊基膦)乙烷,即dCypPe;1,2-二(苯基特丁基膦)乙烷,即Ph(t-Bu)Pe)在室温和压下对苯的光羰化反应性能,得到了预期的反应产物苯甲醛和苯甲醇。它们均经色-质分析 相似文献
58.
59.
《Analytical letters》2012,45(9):1775-1786
ABSTRACT 9,10-anthraquinone (AQ), a photochemically reactive substrate, has been conjugated together with human serum albumin (HSA), and the photoinduced fluorogenic reaction of the HSA-AQ conjugate was studied. This conjugate shows a greatly enhanced photochemical fluorimetric activity compared with that of free AQ. The spectral characteristics of the photoreduction product of the HSA-AQ conjugate was investigated and large blue shifts in both the excitation and emission bands, compared with those of free AQ, were observed. The kinetic behavior of the photoinduced fluorogenic reaction and the effects of some experimental conditions were also investigated. The enhancement in the photoinduced fluorogenic reactivity of HSA-AQ was utilized in the sensitive detection of HSA by a simple in-situ photoinduced kinetic fluorimetric method. The calibration graph was linear over the range 0-1.0x10?6 mol/L HSA. The detection limit was 6.5x10?10 mol/L HSA and the relative standard deviation was 2.7% for 6.0x10?8 mol/L HSA (n=6). 相似文献
60.
Donald J. Burton C.A. Wesolowski Qibo Liu Charles R. Davis 《Journal of fluorine chemistry》2010,131(10):989-995
Methodology directed at the preparation of (Z)-1,2-difluorostilbenes has been evaluated. For symmetrical (Z)-1,2-difluorostilbenes, photochemical isomerization of the isomeric (E)-1,2-difluorostilbenes, and HPLC separation of the mixture of stilbene isomers is a reasonable route to a particular (Z)-stilbene. An alternative approach to both symmetrical and/or unsymmetrical (Z)-1,2-difluorostilbenes has been developed via stereospecific Pd(0) coupling of (E)-1,2-difluoro-aryl-ethenyltributylstannanes under Stille-Liebiskind conditions with aryl idodies. The requisite arylstannanes can be obtained via the reported route developed by Davis or via (E)-1,2-difluorovinyltributylstannane - a new route described in this work. The methodology tolerates almost any functionality in the aryl ring, is easily carried out, is stereospecific and provides the first general route to (Z)-1,2-difluorostilbenes. 相似文献