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531.
Chun Liu ZhiGuo Zhou Yuan Gao Hong Yang BaoGuo Li FuYou Li ChunHui Huang 《中国科学B辑(英文版)》2009,52(6):760-764
A fluorescence turn-on chemosensor based on rhodamine B derivative (FD10) has been developed as a highly sensitive chemosensor
for Hg2+. A prominent fluorescence enhancement was measured in the presence of Hg2+, which was in agreement with the changes in the absorption spectrum. Furthermore, by means of laser scanning fluorescence
microscopy experiments, it was demonstrated that FD10 was cell-permeable and could be used as a fluorescent probe for monitoring
Hg2+ in living cells.
Supported by the National Natural Science Foundation of China (Grant No. 20801015) and Shanghai Leading Academic Discipline
Project (Grant No. B108) 相似文献
532.
533.
以罗丹明B、乙二胺和乙二醛为反应原料,合成了一种新型的荧光增强型识别Fe3+的分子探针(fluorescent probe,FP)。用核磁和质谱对其分子结构进行了表征,并通过荧光光谱研究了FP对Al3+、Pb2+、Cu2+、Cd2+、Mn2+、Hg2+、Mg2+、Ca2+、K+、Na+等不同金属离子的识别性能。研究结果表明:在纯甲醇溶剂中,探针FP对Fe3+的识别具有较好的选择性,且基本不受其他金属离子的干扰;通过Job's曲线可知,探针FP与Fe3+的络合比为1∶3;Fe3+浓度在4×10-4~5×10-3mol/L范围内时,探针FP的荧光强度与Fe3+浓度具有良好的线性关系,线性相关系数为0.995 3。 相似文献
534.
Dr. Thomas Just Sørensen Dr. Dong Shi Prof. Dr. Bo W. Laursen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(21):7046-7049
Rhodamine is one of the most widely used fluorescent dyes. Here, a new synthetic pathway to the popular dyes is reported and the effect of adding four methoxy groups to the molecular structure is investigated. Tetramethoxy‐aminorhodamine ( TMARh ) is found to show superior pH switching compared to the rhodamine without the four methoxy groups, owing to changed properties of the dark “off” state and increased fluorescence intensity in the protonated “on” state. 相似文献
535.
Facile fabrication of g‐C3N4/MIL‐53(Al) composite with enhanced photocatalytic activities under visible‐light irradiation 下载免费PDF全文
A novel visible‐light‐driven g‐C3N4/MIL‐53(Al) composite photocatalyst was successfully prepared using a facile stirring method at room temperature. The g‐C3N4/MIL‐53(Al) composites were characterized and their effects on the photocatalytic activities for rhodamine B degradation were investigated. The g‐C3N4(20 wt%)/MIL‐53(Al) photocatalyst displayed optimal photocatalytic degradation efficiency, which was about five times higher than the photocatalytic activity of pure g‐C3N4. The improved photocatalytic performance of the g‐C3N4/MIL‐53(Al) photocatalyst was predominantly attributed to the efficient separation of electron–hole pairs and the low charge‐transfer resistance. g‐C3N4/MIL‐53(Al) also exhibited excellent stability and reusability. A proposed mechanism for the enhanced photocatalytic activity is also discussed based on the experimental results. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
536.
The IR spectra of 15 N-, 18 O- and 13 C-labelled [VO(sal-gly) (H2O)] (sal-gly = N-salicylideneglycinate) derived from labelled glycine, and the unlabelled analogue are discussed. Assignments of the characteristic ligand and metal-ligand vibrations are based on the effects of the isotopic substitutions. 相似文献
537.
538.
Materialtransportuntersuchungen sind wichtige Hilfsmittel bei der Optimierung der Fahrweise von Aggregaten und Anlagen in der Produktion. Die radioaktive Markierung ermöglicht in vielen Fāllen die Aufnahme von Verweilzeitverteilungen durch die Wand der Anlagen hindurch und gestattet somit – im Gegensatz zu den herkömmlichen Verfahren – Aussagen über die Geschwindigkeitsverteilung und über die axiale Durchmischung des Materials in verschiedenen Teilabschnitten der Anlage ohne Entnahme und Analyse von Proben. Durch Markierung mit 110La wurde der Feststofftransport in Heiβlösern und in Trommeltrocknern der Kaliindustrie untersucht. 相似文献
539.
Y. M. Megahed M. F. Abdel-Wahab A. A. Ismai A. A. Abdel-Hafiz 《Isotopes in environmental and health studies》2013,49(10):357-361
A precise and accurate method is being developed for the determination of T3/T4 ratio. This method depends on using serum of different thyroid cases for the assesment of T3/T4 ratio. It has been found that the best temperature of storage is 0.0 °C to 4 °C before extracting the iodinated tyrosines and thyronines. Iodination with 125I was done according to our previous technique to render the separated thyronine radioactive. Scanning method helped for the determination of T3/T4 ratio. The results were confirmed by sensitivity and recovery test and statistically analyzed. 100 cases were investigated comprising hypo-, eu-, and hyperthyroid cases. 相似文献
540.
A. M. Hussein A. A. Kassem M. ElGarhy E. Abdullah 《Isotopes in environmental and health studies》2013,49(8):327-330
The tissue distribution of colloidal zirconyl phosphate-P32 and its retention following i.m and i.v. injection in mice were studied. About 63 per cent of the i.m. injected P32 activity was retained at the site of injection after 5 days, suggesting the use of the colloid in the local treatment of tumours. The deposition of the colloid in bone and liver after i.v. injection presented zirconyl phosphateP32 as useful in the radiotherapy of bone and liver disease. 相似文献