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111.
112.
Synthesis and cofluorescence of Eu(Y) complexes with salicylic acid and o-phenanthroline 总被引:2,自引:0,他引:2
Xu CJ Xie F Guo XZ Yang H 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,61(9):2005-2008
A series of dinuclear complexes of salicylic acid (HSal) and o-phenanthroline (Phen) with different molar ratios of Eu3+ to Y3+ have been synthesized. Their compositions are Eu(x)Y(1-x) (Sal)3(Phen) (x = 0 to approximately 1). Their UV spectra, IR spectra, and fluorescence spectra were studied. The UV spectra of the complexes reflect essentially absorption of the ligands for the fact that no obvious change of wavelength and band shape is found between the spectra of the complexes and that of the ligands except slight red shift. The IR absorption spectra indicate that salicylic acid is coordinated to the rare earth ions and chemical bonds are formed between rare earth ions and nitrogen atoms of o-phenanthroline. The fluorescence spectra of the complexes indicate that the fluorescence emission intensity of europium ion was enhanced by the addition of Y3+, which is referred to as cofluorescence. These facts show that not only the ligands but also the yttrium complex can transfer the absorbed energy to Eu3+ ion in the complexes. Formation of polynuclear complexes appears to be responsible for cofluorescence. 相似文献
113.
Liang Wang Jun Yue Bai Peng Fei Huang Hong Jing Wang Xiao Wei Wu Yu Qing Zhao 《Mikrochimica acta》2007,158(1-2):73-78
The electrochemical behaviors of uric acid (UA) at the penicillamine (Pen) self-assembled monolayers modified gold electrode
(Pen/Au) have been studied. The Pen/Au electrode is demonstrated to promote the electrochemical response of UA by cyclic voltammetry
(CV). The diffusion coefficient D of UA is 6.97 × 10−6 cm2 s−1. In differential pulse voltammetric (DPV) measurements, the Pen/Au electrode can separate the UA and ascorbic acid (AA) oxidation
potentials by about 120 mV and can be used for the selective determination of UA in the presence of AA. The detection limit
was 1 × 10−6 mol L−1. The modified electrode shows excellent sensitivity, good selectivity and antifouling properties. 相似文献
114.
Wenhua Chen Xue Yao Zhenghui Huang Fei Mao Longfei Guan Yun Tang Hualiang Jiang Jian Li Jin Huang Lubin Jiang Jin Zhu 《中国化学快报》2019,30(1):250-254
A series of novel 2,4-diaminopyrimidine-modified compounds was designed and synthesized. Compound 14 showed micromolar dual inhibitory effect on both FP-2 and PfDHFR, and potential inhibition to the proliferation of P. falciparum 3D7 strain and chloroquine-resistant P. falciparum Dd2 strain. 相似文献
115.
Yang M Wang W Yuan F Zhang X Li J Liang F He B Minch B Wegner G 《Journal of the American Chemical Society》2005,127(43):15107-15111
The synthesis of a block codendrimer (g3-PBE-b-g3-PMDC), composed of a third-generation poly(benzyl ether) (PBE) monodendron and an aliphatic polyether (PMDC) monodendron is reported. In THF/diiospropyl ether (1:1) the PMDC block functions as a "hydrophilic" block, while the PBE acts as a "hydrophobic" block. The codendrimer can form interdigitated layers leading to vesicle formation. Tapping mode atomic force microscopy (AFM), dynamic light scattering (DLS), and transmission electron microscopy (TEM) were used to characterize the vesicles. The effect of molecular architecture on the formation of the interdigitated layers and vesicles was studied. 相似文献
116.
The interaction of Amido black 10B (AB) with DNA in basic medium was studied in the presence of cetyltrimethylammonium bromide (CTMAB) based on the measurements of resonance light scattering (RLS), UV–vis, CD spectra, and RLS imaging. The interaction has been proved to give a ternary complex of CTMAB–DNA–AB in Britton–Robinson buffer of pH 11.55, which exhibits strong negative Cotton effect at 233.3 nm and 642.8 nm, and strong RLS signals characterized at 469 nm. Experiments showed that the enhanced RLS intensities (ΔIRLS) against the mixture of AB and CTMAB are proportional to the concentration of fish sperm DNA (fsDNA) and calf thymus DNA (ctDNA), respectively over the range of 0.03–1.0 and 0.05–1.5 μg ml−1, with the limits of determination (3σ) of 7.3 ng ml−1 for fsDNA and 7.0 ng ml−1 for ctDNA. 相似文献
117.
Three new neolignans, named 1‐deoxycarinatone ( 1 ), isodihydrocarinatidin ( 2 ), and isolicarin A ( 3 ), together with the known neolignan (+)‐dehydrodiisoeugenol ( 4 ), were isolated from mace (the aril of Myristica fragrans Houtt .). Their structures were elucidated as 2‐[(1S)‐2‐(4‐hydroxy‐3‐methoxyphenyl)‐1‐methylethyl]‐6‐methoxy‐4‐(prop‐2‐enyl)phenol ( 1 ), 4‐[(2R,3R)‐2,3‐dihydro‐7‐methoxy‐3‐methyl‐5‐(prop‐2‐enyl)benzofuran‐2‐yl]‐2‐methoxyphenol ( 2 ), and 4‐{(2S,3R)‐2,3‐dihydro‐7‐methoxy‐3‐methyl‐5‐[(1E)‐prop‐1‐enyl]benzofuran‐2‐yl}‐2‐methoxyphenol ( 3 ) on the basis of spectroscopic data. 相似文献
118.
有机硅化合物是半导体工业中产生硅元件的基本原料和有机合成中的重要试剂,是多年来大家研究较多的分子体系之一.本文报导了用同步辐射加速器产生的真空紫外光,电离St(CH3hCI。分子.在50-120n-m波长范围内,测量了各种离子产物与真空紫外光波长的关系,推算得它的绝热电离电势和离子中几个化学键的键能.1实验装置和方法本工作在国家同步辐射实验室光化学实验站进行.进行分子真空紫外光电离研究的实验系统已在文献山中详细描述.同步辐射加速器产生的真空紫外光波长用Ne气的电离势标定,其误差<士0-Inln.单色仪的分辨率为河凸… 相似文献
119.
Synthesis, Characterization and Two-Photon Absorption Properties of a Novel Pyridinium Salt 总被引:2,自引:0,他引:2
A novel pyridinium salt, 2,4-bis[p-(N,N-dimethylamino)styryll-N-metlayl pyridinium iodide (BMSPI) was synthesized and characterized by TG, ^1H NMR spectroscopy and elemental analysis, and the reaction process was studied by using ES-MS. When BMSPI was pumped by a pulsed 1064 nm, 50 ps laser beam, it manifests highly efficient TPA (Two-Photon Absorption) and up-conversion superradiance. The up-conversion efficiency was 6.0% at the pump energy of 4-6 mJ and the lifetime of two-photon fluorescence was measured as 59 ps. 相似文献
120.
Jun Yue Bai Liang Wang Hong Jing Wang Peng Fei Huang Yu Qing Zhao Sheng Di Fan 《Mikrochimica acta》2006,156(3-4):321-326
The electrochemical behavior of epinephrine (EP) at a mercaptoacetic acid (MAA) self-assembled monolayer modified gold electrode
was studied. The MAA/Au electrode is demonstrated to promote the electrochemical response of epinephrine by cyclic voltammetry.
The possible reaction mechanism is also discussed. The diffusion coefficient D of EP is 6.85 × 10−6 cm2 s−1. In 0.1 mol L−1 phosphate buffer (pH 7.20), a sensitive oxidation peak was observed at 0.177 V, and the peak current is proportional to the
concentration of EP in the range of 1.0 × 10−5–2.0 × 10−4 mol L−1 and 1.0 × 10−7–1.0 × 10−6 mol L−1. The detection limit is 5 × 10−8 mol L−1. The modified electrode is highly stable and can be applied to the determination of EP in practical injection samples. The
method is simple, quick, sensitive and accurate. 相似文献