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101.
The complex [Tb0.1Gd0.9(TPTZ)(H2O)6]Cl3·3H2O was prepared through the reaction of 2,4,6-tris-(2-pyridyl)-1,3,5-triazine (TPTZ) with TbCl3:GdCl3 (0.1:0.9) in absolute ethanol at room temperature. Single crystal X-ray diffraction revealed that the metal atom is nine-coordinated
with three nitrogen atoms from one TPTZ ligand and six oxygen atoms from six water molecules. The complex emits intense green
fluorescence under ultraviolet light. The luminescence peaks correspond to the characteristic emission 5D4→7FJ (J = 3–6) transitions of the Tb3+ ion. 相似文献
102.
Mei-Jun Chen Ying-Song Wu Guan-Feng Lin Jing-Yuan HouMing Li Tian-Cai Liu 《Analytica chimica acta》2012
Quantum dots (QDs) with novel photoproperties are not widely used in clinic diagnosis, and homogeneous time-resolved fluorescence assays possess many advantages over current methods for alpha-fetoprotein (AFP) detection. A novel QD-based homogeneous time-resolved fluorescence assay was developed and used for detection of AFP, a primary marker for many cancers and diseases. QD-doped carboxyl-modified polystyrene microparticles (QPs) were prepared by doping oil-soluble QDs possessing a 605 nm emission peak. The antibody conjugates (QPs-E014) were prepared from QPs and an anti-AFP monoclonal antibody, and luminescent terbium chelates (LTCs) were prepared and conjugated to a second anti-AFP monoclonal antibody (LTCs-E010). In a double-antibodies sandwich structure, QPs-E014 and LTCs-E010 were used for detection of AFP, serving as energy acceptor and donor, respectively, with an AFP bridge. The results demonstrated that the luminescence lifetime of these QPs was sufficiently long for use in a time-resolved fluoroassay, with the efficiency of time-resolved Förster resonance transfer (TR-FRET) at 67.3% and the spatial distance of the donor to acceptor calculated to be 66.1 Å. Signals from TR-FRET were found to be proportional to AFP concentrations. The resulting standard curve was log Y = 3.65786 + 0.43863·log X (R = 0.996) with Y the QPs fluorescence intensity and X the AFP concentration; the calculated sensitivity was 0.4 ng mL−1. By assaying test samples against the standard curve, the coefficient of variations was <5%, indicating that QDs were suitable for this homogenous time-resolved fluoroimmunoassay. This work extended the potential applications of QDs in future homogeneous analytical bioassays. In the coming research, hepatitis B surface antigen, another primary marker for hepatocellular carcinoma, will be studied for practical detection using a QD-based homogenous multiplex fluoroimmunoassay. 相似文献
103.
Zhi Chen Ming Fang Peng Ren Xiu‐Hua Li Bin Zhao Dr. Associate Prof. Shi Wei Peng Cheng 《无机化学与普通化学杂志》2008,634(2):382-386
Two novel lanthanide‐based coordination polymers with 2D lattice‐type motif, [Ln2(CAM)3(H2O)4]·2H2O (CAM = 4‐Hydroxypyridine‐2,6‐dicarboxylate; Ln = Tb( 1 ), Pr( 2 )), have been prepared by hydrothermal reaction of Ln(OH)3, CAM and water at 160 °C and characterized by single‐crystal X‐ray diffraction analysis, IR and TGA. The investigation of luminescent property reveals that 1 exhibits characteristic green emission of Tb3+ ions. 相似文献
104.
Cuiling Ren Jinhua Li Jiefang Sun Xingguo Chen Zhide Hu Desheng Xue 《Journal of luminescence》2010,130(1):65-69
In this paper, a new kind of fluorescent nanomaterial with morin modified alumina core and silica shell was prepared. Samples were characterized by transmission electron microscope (TEM), X-ray diffraction (XRD), Fourier transform infrared spectra (FT-IR), photoluminescent (PL) spectroscopy and fluorescence microscope. TEM results indicated that this material could be synthesized in nanometer range. PL spectra suggested that this new synthesized material was photostable and it showed nearly no dye leakage. This was because the dye molecules could form stable complex with the reactive aluminum cations on the surfaces of the alumina particles. The excitation and emission maxima of this new luminescent material were located at 420 and 493 nm, respectively. This new kind of luminescent nanomaterial was prepared by morin, AlCl3 and tetraethyl orthosilicate, which was very important for the large-scale and economic preparation luminescent nanoparticles because these precursors were inexpensive and the preparation process was convenient. 相似文献
105.
This paper presents a theoretical model and corresponding experimental results of the oblique-incidence response of a luminescent
photoelastic coating (LPC). LPCs use a luminescent dye that both partially preserves the stress-modified polarization state
and provides high emission signal strength at oblique surface orientations. These characteristics enable the technique to
acquire full-field strain separated measurements and principal strain directions, potentially on complex three-dimensional
geometries, without the use of supplemental experimental or analytical techniques. Results of a single-layer LPC on a disk
in diametral compression are presented to assess a theoretical model and evaluate the measurement sensitivity.
相似文献
J. P. HubnerEmail: |
106.
Solid complexes of terbium, neodymium and yttrium nitrates with an amide type ligand, N‐benzyl‐2‐(benzyloxy)benzamide ( L ) have been prepared in ethyl acetate and characterized by elemental analysis and IR spectroscopy. The crystal and molecular structures of the complexes Tb L 3(NO3)3, Nd L 3(NO3)3 and Y L 3(NO3)3 have been determined by single crystal X‐ray diffraction. The crystal structures of the complexes are similar. The structures show that the crystal consists of two similar but independent molecules in the asymmetric unit and the metal ion is coordinated toward nine donor atoms, three of which belong to the oxygen atoms of three monodentate ligands and six oxygen atoms from three bidentate nitrates. Furthermore, the RE L 3(NO)3 complex units are linked by the intermolecular hydrogen bonds to form a three‐dimensional net. At the same time, the luminescent properties of the ligand and the complex Tb L 3(NO3)3 were studied as well. 相似文献
107.
Dr. Chen Sun Dr. Zeyu Deng Zhiyuan Li Zhongwei Chen Xuanyu Zhang Dr. Jian Chen Prof. Dr. Haipeng Lu Prof. Dr. Pieremanuele Canepa Prof. Dr. Rui Chen Prof. Dr. Lingling Mao 《Angewandte Chemie (International ed. in English)》2023,62(10):e202216720
Hybrid organic–inorganic antimony halides have attracted increasing attention due to the non-toxicity, stability, and high photoluminescence quantum yield (PLQY). To shed light on the structural factors that contribute to the high PLQY, five pairs of antimony halides with general formula A2SbCl5 and A2Sb2Cl8 are synthesized via two distinct methods and characterized. The A2SbCl5 type adopts square pyramidal [SbCl5] geometry with near-unity PLQY, while the A2Sb2Cl8 adopts seesaw dimmer [Sb2Cl8] geometry with PLQY≈0 %. Through combined data analysis with the literature, we have found that A2SbCl5 series with square pyramidal geometry generally has much longer Sb⋅⋅⋅Sb distances, leading to more expressed lone pairs of SbIII. Additional factors including Sb−Cl distance and stability of antimony chlorides may also affect PLQY. Our targeted synthesis and correlated insights provide efficient tools to precisely form highly emissive materials for optoelectronic applications. 相似文献
108.
《Journal of Coordination Chemistry》2012,65(15):2693-2701
Two metal coordination polymers, [Cd(ipa)(L1)(H2O)]n (1) and [Cd(ipa)(L2)]n (2) [H2ipa?=?isophthalic acid, L1?=?3,5-bis(imidazole-1-yl)pyridine and L2?=?3,5-bis(benzoimidazo-1-ly)pyridine], have been synthesized and structurally characterized by IR, elemental analysis, XRD, and X-ray single-crystal diffraction. Complex 1 shows a twofold cds topological net and 2 features a 3-D pcu topological net. Luminescent properties of 1 and 2 were investigated in the solid state at room temperature. 相似文献
109.
《Journal of Coordination Chemistry》2012,65(16):2948-2956
Two cadmium complexes, {[Cd(a-ptt)(ptt)]·H2O} n (1) and [Cd(a-Hmtt)2(SO4)H2O]·CH3OH (2), have been prepared based on 4-amino-3-(4-pyridine)-5-mercapto-1,2,4-triazole (a-Hptt) and 4-amino-3-methyl-5-mercapto-1,2,4-triazole (a-Hmtt), respectively. In 1, amino-triazole ligand a-Hptt can partly be deaminated and transformed into 3-(4-pyridine)-5-mercapto-triazole (Hptt) under hydrothermal conditions. X-ray diffraction analysis reveals that 1 exhibits an unusual 2-D lampshade-type layer structure in which the amino ligand a-ptt and the deamination ligand ptt display exo-tridentate bridging and bidentate bridging, respectively. Complex 2 is mononuclear and further assembled into a 3-D supramolecular architecture via non-covalent interactions. Complexes 1 and 2 were characterized by elemental analyses, IR, and thermogravimetric analyses. Furthermore, solid-state luminescent properties of 1 and 2 have also been investigated. 相似文献
110.
《Journal of Coordination Chemistry》2012,65(19):3424-3432
Two new isostructural 1-D lanthanide coordination polymers, {[Ln(2,4-dcp)3(phen)] n [(Ln?=?Eu (1); Tb (2)], [2,4-dcp?=?2,4-dichlorophenoxyacetate, phen?=?1,10-phenanthroline], were obtained under hydrothermal conditions and characterized by IR spectroscopy, elemental analyses, thermogravimetry analyses, powder X-ray diffraction, and single-crystal X-ray diffraction. Both structures exhibit similar 1-D infinite chains with a {Ln2(2,4-dcp)6(phen)2} dimeric repeat unit, with lanthanides in an eight-coordinate environment. The results of thermal analysis indicate that 1 and 2 are quite stable to heat. 3-D fluorescence spectra of 1 and 2 were detected at room temperature under excitation and the emission wavelengths of 250–460?nm and 420–750?nm with the same interval of 5?nm, respectively. Interestingly, 1 and 2 possess longer fluorescence lifetimes than other complexes (τ?=?1.61?ms for 1 at 611?nm; 1.79?ms for 2 at 543?nm). 相似文献