Studies on interaction of bovine serum albumin with indo-1 by fluorescence spectroscopic method

The binding-site number was calculated by using fluorescence spectroscopic method with bovine serum albumin(BSA) and Indo-1 as protein and ligand models, respectively. The method for calculating binding-site number in BSA for Indo-1 was developed based on the relationships between the changes of Indo-1 fluorescence intensity and the analytical concentration of BSA. And the interaction of BSA with Indo-1 was investigated comprehensively by using fluorescence techniques as well as fluorescence resonance energy transfer, and the thermodynamic parameters were calculated according to the changes of enthalpy on temperature.,

Effect of annealing on the deformation mechanism of a styrene/n-butyl acrylate copolymer latex film investigated by synchrotron small-angle X-ray scattering

The deformation mechanism of a styrene/n-butyl acrylate copolymer latex film subjected to uniaxial tensile stress was studied by small-angle X-ray scattering. The influence of annealing at 23, 60, 80, and 100 degrees C for 4 h on microscopic deformation processes was elucidated. It was demonstrated that the microscopic deformation mechanism of the latex films transformed gradually from nonaffine deformation behavior to affine deformation behavior with increasing annealing temperature.

Near-infrared polymer light-emitting diodes based on infrared dye doped poly(N-vinylcarbazole) film

Infrared light-emitting diodes possess potential applications in optical communication and safety detection. in this paper, we fabricated near-infrared light-emitting diodes possess potential applications in optical communication and safety detection. in this paper, we fabricated near-infrared polymer light-emitting diode employing a commercial near-infrared (NIR) organic dye as an emissive dopant dispersed within poly(N-vinylcarbazole) (PVK) by spin-casting method. The used device structure was indium tin oxide/3,4-polyethylene-dioxythiophene-polystyrene sulfonate/PVK: NIR dye/Al.

Facile Synthesis and Optical Property of Porous Tin Oxide and Europium-Doped Tin Oxide Nanorods through Thermal Decomposition of the Organotin

Porous SnO2 and SnO2-Eu3+ nanorods have been facilely prepared using triphenyltin hydroxide microrods as precursors. The porous structure of SnO2 nanorods, which was aggregated by small SnO2 nanocrystallites, has been confirmed by TEM images and nitrogen adsorption-desorption isotherms. The optical property of the porous SnO2-Eu3+ nanorods was investigated by UV-vis absorption and photoluminescence spectra.

Ionic liquid-based "all-in-one" synthesis and photoluminescence properties of lanthanide fluorides

A facile route to the synthesis of LnF(3) nanocrystals has been accomplished in three ionic liquids (ILs) (OmimPF(6), OmimBF(4), and BmimPF(6)). The partial hydrolysis of PF6- and BF4- was utilized to introduce a new fluoride source. Uniform LnF(3) (Ln = La, Ce, Pr, Nd, Sm, Eu, Er), Tb3+-doped CeF3, and Eu3+-doped LaF3 nanocrystals could be obtained in a large scale, and the products were up to 0.15 g per 10 mL solvents. In the "all-in-one" systems, the ILs acted as solvents, reaction agents, and templates.

Selective synthesis of hexagonal and monoclinic LaPO4:Eu3+ nanorods by a hydrothermal method

The hexagonal and monoclinic LaPO4:Eu3+ nanorods can be selectively synthesized through a simple hydrothermal method by only adjusting the reaction temperature. Hexagonal and monoclinic LaPO4:Eu3+ nanorods can be prepared at 120 and 180 degrees C, respectively. The phase conversion of LaPO4:Eu3+ under different temperatures is investigated in detail. Moreover, the influence of the temperature on the intensity and the shift of the peaks of the excitation and emission spectra is discussed, and the decay lifetime of the Eu3+ ions of the sample obtained at different temperature also have been investigated in this paper.

Near-infrared luminescent mesoporous MCM-41 materials covalently bonded with ternary thulium complexes

Two beta-diketones 4,4,4-trifluoro-1-2-thenoyl-1,3-butanedione (Htta) and 4,4,4-trifluoro-1-(2-naphthyl)-1,3-butanedione (Htfnb), which contain trifluoroalkyl chain, were selected as the main sensitizer for synthesizing Tm(L)(3)phen (L = tta, tfnb) complexes. The two near-infrared (NIR) luminescent thulium complexes have been covalently bonded to the ordered mesoporous material MCM-41 via a functionalized 1,10-phenanthroline (phen) group 5-(N,N-bis-3-(triethoxysilyl)propyl)ureyl-1,10-phenanthroline (phen-Si) [The resultant mesoporous materials are denoted as Tm(L)(3)phen-MCM-41 (L = tta, tfnb)]. The Tm(L)(3)phen-MCM-41 (L = tta, tfnb) mesoporous materials were characterized by small-angle Xray diffraction (XRD) and N-2 adsorption/desorption, and they show characteristic mesoporous structure of MCM-41.

Novel hybrid periodic mesoporous organosilica material grafting with Tb complex: Synthesis, characterization and photoluminescence property

A novel periodic mesoporous organosilica (PMO) material was synthesized through one-step co-condensation of 1,2-bis(triethoxysilyl)ethane (BTESE) and benzoic acid-functionalized organosilane (BA-Si) using cetyltrimethylammonium bromide (CTAB) as a structure-directing agent under basic conditions. The materials were fully characterized by FTIR, XRD, N-2 adsorption-desorption isotherms and FESEM. FTIR spectra proved that BA-Si was successfully incorporated into the PMO materials (PMOs) via benzyl group as a linker. XRD and N-2 adsorption-desorption isotherms revealed the characteristic mesoporous structure with highly uniform pore size distributions. FESEM confirmed that the morphology of the PMOs was significantly dependent cri the molar ratio of two organosilica precursors.

A study on the near-infrared luminescent properties of xerogel materials doped with dysprosium complexes

A series of dysprosium complex doped xerogels with the same first ligand (acac = acetylacetone) and different neutral ligands were synthesized in situ via a sol-gel process. The Fourier transform infrared (FTIR) spectra, diffuse reflectance (DR) spectra, and near-infrared (NIR) luminescent properties of dysprosium complexes and dysprosium complex doped xerogels are described in detail. The results reveal that the dysprosium complex is successfully synthesized in situ in the corresponding xerogel. Excitation at the maximum absorption wavelength of the ligands resulted in the characteristic NIR luminescence of the Dy3+ ion, which contributes to the energy transfer from the ligands to the central Dy3+ ion in both the dysprosium complexes and xerogels via an antenna effect.

Near-infrared luminescent properties and natural lifetime calculation of a novel Er3+ complex

in this communication, a novel Er3+ complex Er(PT)(3)TPPO [PT = 1-phenyl-3-methyl-4-tert-butylbenzoyl-5-pyrazolone, TPPO = triphenyl phosphine oxide] is successfully synthesized and characterized by elemental analysis and single-crystal X-ray diffraction. Its optical properties and the energy transfer process from the ligand PT to the Er3+ ion are investigated, the typical near-infrared (NIR) luminescence (centered at around 1530 nm) is attributed to the I-4(13/2) -> I-4(15/2) transition of Er3+ ion which results from the efficient energy transfer from PT to Er3+ ion (an antenna effect). The wider full width at half maximum (78 nm) peaked at 1530 nm in the emission spectrum and the Judd-Ofelt theory calculation on the radiative properties suggest that Er(PT)(3)TPPO should be a promising candidate for tunable lasers and planar optical amplifiers.

The near-infrared optical properties of an Nd (III) complex and its potential application in electroluminescence

A trivalent neodymium ion (Nd3+) complex Nd(PM)(3)(TP)(2) was synthesized, and its optical properties was studied by introducing Judd-Ofelt theory to calculate the radiative transition rate and the radiative decay time of the F-4(3/2) -> (4)l(J), transitions in this Nd(III) complex. The strong emissions of this complex at near-infrared region were owing to the efficient energy transfer from ligands to center metal ion. The potential application of this complex in NIR electroluminescence was studied by fabricating several devices. The maximum NIR irradiance was obtained as 2.1 mW/m(2) at 16.5 V.

Novel Near-Infrared Luminescent Hybrid Materials Covalently Linking with Lanthanide [Nd(III), Er(III), Yb(III), and Sm(III)] Complexes via a Primary beta-Diketone Ligand: Synthesis and Photophysical Studies

A series of novel, colorless, and transparent sot-gel derived hybrid materials Ln-DBM-Si covalently grafted with Ln(DBM-OH)(3)center dot 2H(2)O (where DBM-OH = o-hydroxydibenzoylmethane, Ln = Nd, Er, Yb, and Sin) were prepared through the primary beta-diketone ligand DBM-OH. The structures and optical properties of Ln-DBM-Si were studied in detail. The investigation results revealed that the lanthanide complexes were successfully in situ grafted into the corresponding hybrids Ln-DBM-Si. Upon excitation at the maximum absorption of ligands, the resultant materials displayed excellent near-infrared luminescence.

Near-infrared luminescent xerogel materials covalently bonded with ternary lanthanide [Er(III), Nd(III), Yb(III), Sm(III)] complexes

A beta-diketone ligand 4,4,5,5,5-pentafluoro-1-(2-naphthyl)-1,3-butanedione (Hpfnp), which contains a pentafluoroalkyl chain, was synthesized as the main sensitizer for synthesizing new near-infrared (NIR) luminescent Ln(pfnp)(3)phen (phen = 1,10-phenanthroline) (Ln = Er, Nd, Yb, Sm) complexes. At the same time, a series of lanthanide complexes covalently bonded to xerogels by the ligand 5-(N,N-bis-3-(triethoxysilyl)propyl)ureyl-1,10-phenanthroline (phen-Si) were synthesized in situ via a sol-gel process. [The obtained materials are denoted as xerogel-bonded Ln complexes (Ln = Er, Nd, Yb, Sm).] The single crystal structures of the Ln(pfnp) 3phen complexes were determined.

Thiacalix[4]arene-Supported Planar Ln(4) (Ln = Tb-III, Dy-III) Clusters: Toward Luminescent and Magnetic Bifunctional Materials

This paper reports the syntheses, crystal structures, and luminescent and magnetic properties of four tetranuclear Tb-III (1 and 3) and Dy-III (2 and 4) complexes supported by p-phenylthiacalix[4]arene (H(4)PTC4A) and p-tert-butylthiacalix-[4]arene (H(4)TC4A). All four frameworks can be formulated as [Ln(4)(III)(PTC4A/TC4A)(2)(mu(4)-OH)Cl-3(CH3OH)(2)(H2O)(3)], and some methanol and water solvent molecules are occupied in the interstices. The compounds are featured with a sandwichlike unit constructed by two tail-to-tail calixarene molecules and a planar tetragonal (mu(4)-OH)Ln(4) cluster. The photoluminescent analyses suggest that there is an efficient ligand-to-Ln(III) energy transfer for compounds 1-3 and H(4)PTC4A is a more efficient "antenna" than H(4)TC4A.

White Electroluminescence from a Phosphonate-Functionalized Single-Polymer System with Electron-Trapping Effect

A novel strategy for obtaining white electroluminescence (EL) is based on the mechanism of electron trapping on host. Phosphonate-functionalized polyfluorene is chosen as host owing to its strong electron affinity. Electrons are confined mostly by host pendants in the EL process, which suppresses charge transfer from host to dopant. White EL with CIE coordinates of (0.34,0.35) is achieved.