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The ternary oxide phase Sr6Y2Al4O15 (SYA) was synthesized and the crystal structure was determined by using the X-ray powder diffraction data. Structure of the phase can be considered as an oxygen-deficient perovskite Sr(Y1/3Al2/3)O-2.5 and has a monoclinic C2 (S.G. No. 5) unit cell with the unit cell parameters: a=17.597(1) angstrom, b=5.7408(1) angstrom, c=7.6860(1) angstrom. beta =90.7659(3)degrees, V-cell =776.37(1) angstrom(3), Z=2. By bond parameter analysis and first-principle calculations, we confirmed the reasonability of our crystal structure model. According to the calculated band structure, SYA has an indirect band gap similar to 4.3 eV and a direct band gap similar to 4.4 eV, which is wide to be transparent to UV and visible lights. We also synthesized other rare-earth isomorphs Sr(6)Ln(2)Al(4)O(15) (Ln=Tb, Dy, Ho, Er, Tm, Yb and Lu) and obtained their cell parameters. (C) 2012 Elsevier Inc. All rights reserved.

Two new complexes (Cp)2Ti (Cin)2 and (Cp)2Ti (Tzea)2 (Cp= Cyclopentadienyl η5-C5H5) have been synthesized in THF by the reaction of HCin (Cincofen, 2-phenylquinoline-4-carboxylic add) or HTzea (5-phenyltetrazolyl-2-ethanoic acid) with (Cp)2TiCl2, and characterized by elemental analyses, IR, 1H NMR and 13C NMR, UV spectra, molar conductivity, TGDTA. In the complexes the carboxyl groups are coordinated to Ti(IV) in a monodentate manner. The inhibitory actions of the complexes on mice ear tumefaction caused by croton oil and the rat foot granulation growth produced by cotton wool are higher than those of the corresponding ligands HCin, HTzea and [(Cp)2TiCl2], while their toxicities are lower than those of the free ligands.

The phosphor Y2SiO5:Ce3+ was prepared by a sol-gel method and the particle growth process was investigated by XRD, SEM and TEM. After heating at 400 °C, the as-dried gel became a powder composed of mixed phases of polycrystalline Y2O3 and amorphous SiO2. With an increase in temperature, the crystallinity of Y2O3 improved. The sample quickly changed to the pure Y2SiO5 phase when it was heated at 1400 °C for 10 min. SEM indicated that the as-dried gel consisted of large porous particles. At an annealing temperature of higher than 400 °C, the pores in the large particles gradually expanded and grains started to appear. Consequently, the large particles disintegrated into small particles. When the sample was heated at 1400 °C, we obtained fine phosphor particles (around 2 μm) with smooth surfaces. The optimized condition for the preparation of the Y2SiO5:Ce3+ phosphor was to heat at 1400 °C for 2 h.

2-Hydroxybenzylidene-2-phenylquinoline-4-carbonylhydrazone (H2L) and five Ln(III) complexes, [Ln(H2L)(NO3)2]NO3 [Ln = La (1), Pr (2), Sm (3), Eu (4), and Tb (5)], have been synthesized and characterized by 1H NMR, elemental analysis, conductivity measurements, mass spectra, IR spectra, and UV spectra. The interaction of these complexes with calf thymus DNA was investigated by UV absorption spectroscopy, fluorescence spectroscopy, circular dichroism spectroscopy and viscosity measurements. Results suggest that these complexes bind to DNA via groove binding.

A series of pH and temperature-responsive (N,N-diethylacrylamide-co-methylacrylic acid) copolymers were synthesized by radical copolymerization and characterized by elemental analysis, Fourier-transform infrared (FT-IR), nuclear magnetic resonance (NMR)1H,13C and LLS. The effects of salt and pH on the phase transition behaviors of the copolymers were investigated by UV. With increasing NaCl concentration, significant salt effects on their phase transition behaviors were observed. UV spectroscopic studies showed that the phase transition became faster with increasing NaCl concentration. In addition, the phase transition behaviors of copolymers were sensitive to pH. The pH and temperature sensitivity of these copolymers would make an interesting drug delivery system.

A coating method with precipitating process was developed to reduce the particle size and to improve the particle dispersion of Y3Al5O12:Tb3+ phosphor prepared by sol–gel method. The particle morphology was observed by using SEM and TEM; and the particle size and its dispersion was measured by using laser scattering technique. Several coating materials were tested. Among them, Al2(SiO3)3 coating not only reduced the particle size from several micrometers to ∼1 μm and improved the particle dispersion, but also well kept luminescent intensities and improved the duration of the phosphor under the bombardment of cathode ray. The mechanism of the particle size reduction was proposed.

Cobalt is an essential microelements in many biological processes involving enzymatic activity. We found that Zn2+ and Mg2+, which are in the active site of native calf intestine alkaline phosphatase (CIP), can be replaced by Co2+ directly in solution. The effect of Co2+ concentration on the substitution reaction was examined at ratios of [Co2+]/[CIP] from 0:1 to 8:1. The quantity of Zn2+ in CIP decreased progressively as the ratio was increased, but the amount of Mg2+ changed in irrregular fashion. A series of active site models of the reaction mechanism of CIP are proposed. Low pH was found to promote the replacement of Mg2+ by Co2+. To understand how the substitution affects the enzyme, we also solved the secondary structure of CIP after reaction with Co2+ in different conditions.

N1,N1-Dimethylbiguanide hydrochloride (HDMBG·HCl) was introduced as an oral glucose-lowering agent to treat non-insulin dependent diabetes mellitus. In this paper, two solid complexes–trichlorotris(N5-benzoyl-N1,N1-dimethylbiguanidato)neodymium, [Nd(BDMBG)3Cl3), and chlorobis-[N5-(o-carboxybenzoyl)-N1,N1- dimethylbiguanidato]neodymium, [Nd(CDMBG)2Cl], were synthesized and characterized by elemental analyses, fluorescence spectra, IR, UV, DG, DTA etc. Biological testings were conducted by diabetic rats and ESR The results showed that both the antidiabetic activity and the inhibition rates (Ih) to superoxide anion free radical O2− on lipid are in the order as follows: Nd(SDMBG)3 [tris(N5-salicyloyl-N1,N1-dimethylbiguanidato)neodymium]>Nd(CDMBG)2Cl≈HDMBG·HCl>Nd(BDMBG)3Cl3. It was concluded that different substituents at the o-position of the benzoyl group may affect these two kinds of behaviour to a great extent.

The interaction of gatifloxacin (HGA) with bovine serum albumin (BSA) at 15 and 37 °C has been investigated by fluorescence quenching spectroscopy in aqueous solution. The bimolecular quenching rate constant was determined by Stern-Volmer curves and the values were Kq=9.28×1012 L·mol−1·s−1 (15 °C) and Kq=8.51×1012 L·mol−1·s−1 (37 °C). The results showed that the fluorescence quenching mechanism of BSA by HGA was a static quenching procedure. The thermodynamic parameters indicated that electrostatic forces played major role in the interaction of BSA with HGA. Studies on the relationship between the concentration of HGA and the fluorescence intensity of BSA >showed that BSA and HGA bound at the molar ratio 1:1 and the equilibrium constant K0 was 6.80×104 L·mol−1. The binding distances between BSA and HGA and the energy transfer efficiency were obtained based on the FOrster's theory.

The compounds Sr6Ln2Al4O15 (Ln: Y, Tb, Dy, Ho, Er, Tm, Yb, Lu) are prepared by solid state reactions of stoichiometric amounts of SrCO3, Ln2O3, and Al2O3 (alumina crucibles, 1500 °C, 12 h).

A novel copper(II) thiocyanate complex with 4-(dimethylamino)pyridine (DMAP) and N,N-dimethylformamide (DMF), [Cu(DMAP)2(SCN)2(DMF)2], was synthesized. The title complex was crystallized in the triclinic system, space group P1 with a = 8.476(1)A, b = 9.404(1)A, c = 9.924(1)A, α = 91.186(2)°, β = 113.989(3)°, γ = 103.543(2)°, V = 696.6(2)A3 and Z = 1. In the title complex, the Cu(II) atom is placed in a centrosymmetric octahedral environment. The molecules are linked by two kinds of weak hydrogen-bonds, C-H…O and C-H…S, generating an extended two-dimensional supramolecular network structure in the ab plane.

The title POM-based organic-inorganic hybrid compound consists of one Anderson-type polyoxoanion, two [Cu(2,2′-bipy)Cl]+ cations, five Na+ cations and fourteen coordination H2O molecules and two solvent H2O molecules; the polyoxoanion was linked by Na+ to form a 2D layer. A 2D organic layer is also formed through a π-π stacking interaction. Through weak interactions between the adjacent layers, a 3D supramolecular compound is formed.

The title compound, C22H19N3O3, was synthesized and the structure was investigated by X-ray crystallography. It crystallizes in the monoclinic system, space group P21/c with a = 14.8281(15)A, b = 11.8051(14)A, c = 11.2260(11)A, β = 106.744(2)°, V = 1881.8(3)A3, Z = 4, R = 0.0489. The N-H…O hydrogen bonds between the compound and the solvent molecule stabilize the crystal structure by causing the formation of a one-dimensional chain structure.

Y 3 Al 5 O 12 :Tb 3+ phosphor was prepared by using a sol-gel method and the process of particle growth was investigated by X-ray diffraction, scanning electron microscopy, particle size, and Brunauer-Emmett-Teller surface area measurements. As-dried Y 3 Al 5 O 12 :Tb 3+ precursor is amorphous bulk. After heating above 800°C, the samples become polycrystalline powders. The low-temperature heated sample (e.g., 900°C) has a porous texture with large particle size (>10 μm). When the samples are heated at higher temperatures (e.g., 1100°C), the pores become larger and the grains start to appear. When the samples are heated at 1400°C, the large-size particles break into small particles (∼ 1 μm), which are actually agglomerated particles by even smaller grains (in submicrometer scale). Under the excitations of the low-voltage cathode ray (< 1500 V), the phosphor prepared in this sol-gel method has brighter cathodoluminescent intensity than the commercial phosphor.