982 resultados para 1,10-Phenanthroline


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Undoped and Tb3+ (1-10 mol%) doped CeO2 nanophosphors were synthesized by low temperature solution combustion method. The combustion derived products were well studied by Powder X-ray diffraction (PXRD), Scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and Ultraviolet visible (UV-Vis) characterizations. The thermoluminescence (TL) glow curves of CeO2: Tb3+ (1-10 mol%) nanophosphors exposed to c source (60Co) for various doses were discussed for the first time. Two TL glow peaks recorded at 182 and 262 degrees C respectively. The TL intensity at 262 degrees C peak increases linearly in the dose range 0.5-7 kGy. Further, this peak was well defined, intense and glow peak structure does not change with c-dose as a result, it was quite useful in TL dosimetry of ionizing radiations. The kinetic parameters associated with the glow peak were estimated using Chen's half width method. The photoluminescence emission (PLE) spectra consists of characteristic peaks at 544 and 655 nm which were attributed to D-5(4) -> F-7(5) and D-5(4) -> F-7(2) transitions of Tb3+ ions. The optimal concentration of Tb3+ ions was found to be 7 mol%. The color co-ordinates of CeO2: Tb3+ (1-10 mol%) located in green region. Hence, this phosphor was quite useful for display applications. (C) 2013 Elsevier B. V. All rights reserved.

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Six new mixed-ligand cobalt(III) complexes of formulation Co(N-N)(2)(O-O)](ClO4)(2) (1-6), where N-N is a N,N-donor phenanthroline base, namely, 1,10-phenanthroline (phen in 1, 2), dipyrido3,2-d:2',3'-f] quinoxaline (dpq in 3, 4), and dipyrido3,2-a:2',3'-c]phenazine (dppz in 5, 6), O-O is acetylacetonate (acac in 1, 3, 5) or curcumin (bis(4-hydroxy-3-methoxyphenyl)-1,6-diene-3,5-dione, cur in 2, 4, 6), have been synthesized and characterized. The X-ray crystal structures of complex 1 (as PF6- salt, 1a) and 3 show distorted octahedral geometries formed by the CoN4O2 core. The complexes 1, 3 and 5 having the simple acac ligand are prepared as control species to understand the role of curcumin. The optimized geometries and the frontier orbitals of the curcumin complexes 2, 4, and 6 are obtained from the DFT calculations. The complexes 2, 4, and 6 having the photoactive curcumin moiety display an absorption band in the visible region near 420 nm and show remarkable photocytotoxicity in HeLa cancer cells with respective IC50 values of 7.4 mu M, 5.1 mu M and 1.6 mu M while being much less toxic in dark. MTT assay using complex 6 shows that it is not significantly photocytotoxic to MCF-10A normal cells. The control complexes having the acac ligand are non-toxic both in the presence and absence of light. The cell death is apoptotic in nature and triggered by the photogeneration of reactive oxygen species. Fluorescence imaging experiments on HeLa cells reveals that complex 6 accumulated primarily inside the mitochondria. Human serum albumin (HSA) binding experiments show that the complexes bind HSA with good affinity, but 6 binds with the highest affinity, with a K-b value of 9.8 x 10(5) M-1. Thus, complex 6 with its negligible toxicity in the dark and in normal cells but remarkable toxicity in visible light holds significant photochemotherapeutic potential.

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Die stark rückläufige Tendenz des Dorschbestandes in der zentralen Ostsee, östlich von Bornholm, über die in den letzten Jahren berichtet wurde, hält nach den Untersuchungen des FFK "Solea" (31.1. - 10.2.1989)an. Im Bornholm Becken lag der durchschnittliche Grundschleppnetzfang je Stunde auf Wassertiefen flacher als 75 m, wo ausreichende Sauerstoffverhältnisse am Boden waren, im EG-Bereich mit 2,5 Korb nochmals niedriger als 1988 (3 Korb). Er lag damit fast um 2/3 niedriger als im langjährigen Mittel 1980-1986. Die besten Fänge wurden mit jeweils 3,5 Korb im Ostzipfel des EG-Meeres, im sogenannten "Bermuda Dreieck", und südlich von Nexö auf jeweils 72 m Wassertiefe erzielt. Im großen und ganzen war der Dorsch im Wassertiefenbereich zwischen 50 und 75 m des Bornholm Beckens recht gleichmäßig verteilt.

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利用能量为60-80MeV的~(12)C束流,通过~197An(~(12)C,3n)~206At反应研究了~206At核的高自旋能级结构.用7台BGO(AC)HPGe探测器和一台用于探测低能γ射线的平面型HPGe探测器进行了γ射线的激发函数、γ-γ-t符合及γ射线的角分布测量.基于这些测量,首次建立了包括25条γ跃迁的~206At高自旋能级纲图.确定了一个半寿命为(908±400)ns、自旋和宇称为10的同质异能态.基于较重的双奇核~(208,210 )At能级结构的系统性,对~(206)At的10~-同质异能态进行了讨论.

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A supramolecular complex [Cu(phen)(2)H2O]{[Cu(phen)(H2O)](2)[C6AS]}center dot 2.5H(2)O (phen = 1,10'-phenanthroline and C6AS = p-sulfonatocalix[6]arene) has been synthesized under hydrothermal condition, and characterized by IR spectroscopy, TG analysis and single crystal X-ray diffraction. In the structure, unprecedented 1D ({[Cu(phen)(H2O)](2)[C(6)AS]}(2-))(n) coordination chains (exactly being belts) are stacked into some 2D layers by the pi center dot center dot center dot pi stacking interactions, which are further interconnected into a 3D extended structure by hydrogen bonding.

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Two copper-organic framework supramolecular assemblies of p-sulfonatocalix[4]arene and 1,10-phenanthroline Cu-2[C12H8N2][C28H20S4O16][H2O](23.5) (1) and Cu-3[C12H8N2](3)[C28H19S4O16]Cl[H2O](17.6) (2) were obtained by pH-dependent synthesis at room temperature. Both structures show ID water-filled channels (rectangular shape in I and triangular in 2) with the solvent-accessible volume occupying 30.8% (1) and 24.2% (2) of the unit-cell volume, respectively. The calixarene molecules in both structures assume analogous cone shapes of C-2 nu symmetry instead of the conventional C-4 nu symmetry. Their connecting to different amounts of copper/phenanthroline cations leads to the formation of different structures.

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The ligand Hhfth [4,4,5,5,6,6,6-heptafluoro-1-(2-thienyl)hexane-1,3-dione], which contains a heptafluoropropyl group, has been used to synthesize several new ternary lanthanide complexes (Ln = Er, Ho, Yb, Nd) in which the synergistic ligand is 1,10-phenanthroline (phen) or 2,2'-bipyridine (bipy). The two series of complexes are [Ln(hfth)(3)phen] [abbreviated as (Ln)1, where Ln = Er, Ho, Yb] and [Ln(hfth)(3)bipy] [abbreviated as (Ln)2, where Ln = Er, Ho, Yb, Nd]. Members of the two series have been structurally characterized. The growth morphology, diffuse reflectance (DR) spectra, thermogravimetric analyses, and photophysical studies of these complexes are described in detail. After ligand-mediated excitation of the complexes, they all show the characteristic near-infrared (NIR) luminescence of the corresponding Ln(3+) ions (Ln = Er, Ho, Yb, Nd). This is attributed to efficient energy transfer from the ligands to the central Ln(3+) ions, i.e. an antenna effect. The heptafluorinated substituent in the main hfth sensitizer serves to reduce the degree of vibrational quenching. With these NIR-luminescent lanthanide complexes, the luminescent spectral region from 1300 to 1600 nm, which is of particular interest for telecommunication applications, can be covered completely.

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在合成BCPDA基础上 ,对甲胎蛋白抗体与BCPDA连接及与铕离子螯合条件进行了研究。BCPDA与甲胎蛋白抗体反应后 ,分离纯化最佳淋洗液为pH9.1的0.1mol/L碳酸盐缓冲溶液 ,BCPDA用量为甲胎蛋白抗体量 (mol)的120~160倍;反应时间为30min。讨论了Eu3+ BCPDA AFP抗体螯合物的荧光光谱 ,最佳温育时间为60min,体系pH值为7.8的Tris HCl溶液。当Eu3+ 浓度为10-6mol/L时,BCPDA的检出限为4.3×10-11mol/L。

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尽管多金属氧酸盐 (POMs)的研究已有180多年的历史,但大量的POMs结构在最近几十年才被陆续解析出来[1~4].其中 ,同多钒酸盐由于钒配位几何形状的多样性,结构最为丰富 ,例如:[V4 O12 ]4-[5],[V5O14 ]3-[6],[V10 O2 8]6-[7] ,[V15O4 2 ]9-[8],[V13 O3 4 ]3-[9].值得注意的是,在这些化合物中,钒的化合价均处于最高氧化态+5价.由于+4价钒不易在溶液中(尤其是水中)稳定存在,因此在以往的常压溶液合成中具有混合价态的同多钒酸盐报道很少.与饱和价态的同多钒酸盐相比,混价多钒酸盐具有更为新奇的电荷分布和拓扑学几何构型,并且在 POMs的理论研究和抗病毒药物、电存储材料以及磁性材料等应用领域有特殊的研究和开发价值[1,10,11].因此,制备具有混价的新型同多钒酸盐一直倍受关注.近年来,水热合成技术的引入使同多钒酸盐合成化学迅速发展.水热体系提供了一个特殊的反应环境 [12 ],使制备各种具有混合价态的同多钒酸盐成为可能.Müller等[13]对这一领域开...

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Organo-functionalized MCM-41 containing non-covalently linked 1,10-phenanthroline (denoted as Phen-MCM-41) was synthesized by template-directed co-condensation of tetraethoxysilane and the modified phenanthroline (denoted as Phen-Si). XRD, FTIR, UV/VIS spectroscopy as well as luminescence spectroscopy were employed to characterize Phen-MCM-41. No disintegration or loss of the Phen-Si during the solvent extraction procedure could be observed. When monitored by the ligand absorption wavelength (272 nm), the undoped MCM-41 produces a broad band emission centered at 450 run, whereas europium (III) doped Phen-MCM-41 displays the emission of the Eu3+, i.e., D-5(0) --> F-7(J) (J = 0, 1, 2, 3, 4) transition lines due to the energy transfer from the ligands to Eu3+ as well as a broad band emission centered at 442 nm.

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分别合成了稀土(Eu3+和Tb3+)与柠檬酸、1,10 菲咯啉配位的稀土配合物。通过元素分析和红外分析确定了配合物的组成。通过荧光光谱与荧光寿命的测试,研究了它们的荧光性质。结果表明当铽掺入配合物后,铽能极大地增强铕的特征荧光,而铽的荧光被严重猝灭,其荧光强度以指数形式衰减。铕的荧光在铽荧光猝灭最严重时,被增强的效果最好,铕的荧光强度是荧光增强效果和铕的含量共同作用的结果,当铕与铽的浓度比为6∶4时能得到相应的铕的荧光最强的配合物。

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Three bridging ligands (L) and their binuclear phenanthroline ruthenium(II) complexes {[Ru(1,10-phenanthroline)(2)](2)(L)}(PF6)(4) were synthesized and characterized by IR, H-1 NMR, and elemental analysis, where L are 1,8-adipoylamido-bis(1,10-phenanthroline-5-yl) (L-1), 1,11-azelaoylamidobis(1, 10-phenanthroline-5-yl) (L-2), and p-phthaloylamido-bis(1,10-phenanthroline-5-yl) (L-3).

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Infrared emission at 1.54 mu m excited optically and electrically from an erbium organic compound tris(acetylacetonato)(1,10-phenanthroline) erbium [Er(acac)(3)(phen)] is observed. The rare-earth complex is dispersed into a polymer matrix of poly(N-vinylcarbazole) (PVK) to fabricate an electroluminescent (EL) device with an ITO/PVK:Er(acac)(3)(phen)/Al:Li/Ag structure, where ITO represents indium-tin-oxide-coated glass. The device shows infrared EL emission at 1.54 mu m, which suggests a simple and cheap method to obtain a light source for 1.54-mu m-wavelength devices in optical communications. (C) 2000 American Institute of Physics. [S0021-8979(00)00301-7].

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Some novel binary and ternary complexes of rare earth(Gd, Eu,Tb) with N-Phenylanthranilic acid and 1,10-Phenanthroline were synthesized by homogenous precipitation and their compositions were characterized by,elemental analysis, IR spectra and UV-Vis spectra, The triplet state energies of N-Phenylanthranilic acid was determined to be 24 330 cm(-1) with the phosphorescence spectra of its gadolinium complexes and the energy match between the ligand and the central rare earth ions was studied. The photophysical properties such as luminescence properties and intramolecular energy transfer match between rare earth ions and ligands and between ligands were discussed. The result indicates that terbium complexes with N-Phenylanthranilic acid and 1,10-Phenanthroline have excellent luminescence properties.