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Sr3SiO5 phosphors co-doped with Eu2+ and Tb3+ were prepared by a conventional solid-state reaction method. The prepared Sr3SiO5:Eu2+,Tb3+,Li+ phosphors had characteristic luminescent spectra excited under near-UV excitation in which both the broadband spectrum assigned to Eu2+ and the line spectrum assigned to Tb3+ are observed, although Tb3+ is inactive with this photon energy in general. For Eu2+–Tb3+ codoped Sr3SiO5, energy transfer process takes place and the mechanism is ascribed to the overlap between the shorter Eu2+ luminescence band from the Sr3SiO5 crystal structure with two Sr sites and 5D4 energy level of Tb3+ ion. Due to the energy transfer, PL intensity of Eu2+ emission increased about 26 %. We suggest that this enhancement mechanism could shed light on the potential applications in white light-emitting diodes excited by near-UV light. In addition, the emission peak position near the orange region indicates that our system is a step towards a new class of wavelength sources for artificial lighting with improved PL intensity and lower energy consumption.

Barium orthotitanate (Ba2TiO4) was prepared by heating at 1250°C for 2 h. The thermal stability of Ba2TiO4 and the phase transformation between the low-temperature monoclinic polymorph (β-Ba2TiO4) and the high-temperature orthorhombic polymorph (α′-Ba2TiO4) were examined by X-ray diffraction. Ba2TiO4 can be corroded by CO2 below 700°C forming BaCO3 and BaTiO3, which is reversible above 750°C. A martensitic transformation from β-Ba2TiO4 to α′-Ba2TiO4 starts at ∼100°C and ends at ∼220°C in heating process. The transformation hysteresis loop is ∼200°C. α′-Ba2TiO4 can be stabilized to room temperature by doping small amount of aliovalent ion Nd3+ (1.5 mole%) or relatively large amount of isovalent ion Sr2+ (10 mole%). After annealing the doped samples at low temperatures (e.g., below 1100°C), for the Nd-doped sample, α′-Ba2TiO4 can be partially transformed to β-Ba2TiO4, whereas the Sr-doped sample is stably kept as α′-Ba2TiO4.

A new 1D cadmium coordination polymer [Cd(PhCOO)2(bbbm)] n (1) (bbbm = 1,1′-(1,4-butanediyl)bis-1H-benzimidazole ) is synthesized under hydrothermal conditions and characterized by elemental analysis, IR, TG, and X-ray single-crystal diffraction. Compound 1 crystallizes in the triclinic system, space group P-1 with a = 10.4289(17) A, b = 12.5198(9) A, c = 12.6130(9) A, α = 118.4260(10)°, β = 95.1990(10)°, γ = 94.3820(10)°, V = 1428.8(3) A3, Z = 2. In the structure of 1, each cadmium center is six-coordinated in a strongly distorted octahedron by two N and four O atoms; an infinite one-dimensional linear chain was built by the flexible bbbm ligand that adopts a bis-monodentate bridging mode linking CdII atoms.

The relation between lead (Pb) and iron (Fe) becomes increasingly concerned because they are both divalent metals that are absorbed by the same intestinal mechanism, and Pb exposure and Fe deficiency in the developmental brain, as well as Fe overload in the aged brain, can cause cognitive deficits. However, the interaction between Pb exposure and Fe status in the brain has not been established. Therefore, in the current study, we examined the effects of maternal ingestion of Pb in drinking water during gestation and lactation on the Fe status and the expression of divalent metal transporter 1 (DMT1) and ferroportin 1 (FP1) in the brain of offspring. The offspring were followed through old age, with measurements taken at postnatal week 3 (PNW3), 41 (PNW41) and 70 (PNW70). Pb exposure increases the Fe content in the old-aged rats' brain, which might be not subjected to DMT1 mediating, but may be associated with the decrease expression of FP1. Furthermore, the effect of Pb on FP1 expression is regulated at transcriptional and posttranscriptional levels. The perturbation in Fe homeostasis may contribute to the neurotoxicology consequences induced by Pb exposure, and FP1 may play a role in Pb-induced Fe cumulation in the brain.

Based on three structurally related flexible bis(5,6-dimethylbenzimidazole) ligand, five novel metal–organic CdII coordination architectures: from 0D to 3D structures CdII complexes have been hydrothermally synthesized and structurally characterized, namely, Cd2I4(L1)2 (1), [CdCl2(L1)]n (2), [CdCl2(L2)]n (3), {[Cd(chdc)(L2)0.5]·H2O}n (4), {[Cd(pydca)(L3)0.5(H2O)2]·H2O}n (5) (where L1 = 1,2-bis(5,6-dimethylbenzimidazole)ethane, L2 = 1,3-bis(5,6-dimethylbenzimidazole)propane, L3 = 1,4-bis(5,6-dimethylbenzimidazole)butane, H2chdc = 1,4-cyclohexanedicarboxylic acid, H2pydca = pyridine-2,6-dicarboxylic acid). A discrete binuclear [2 + 2] metallomacrocycles cadmium(II) complex of 1 is 0D, 3 and 5 exhibit one-dimensional helical and zigzag chain structures, respectively. 4 Forms a 2D layer with sql net topology bridged by carboxylate anion and L2, while 2 is an overall 3D array with the diamond topology (dia). In these complexes, the influences of anions coordination on the framework formation were observed and discussed. These results indicate the spacer length of the ligands and anions play important roles in controlling the diversity structural topologies of such metal–organic coordination architectures. The thermogravimetric analyses, X-ray powder diffraction and solid-state luminescent properties of the complexes have also been investigated.

Three flexible α,ѡ-bis(5,6-dimethylbenzimidazolyl)alkane ligands with different spacers were reacted with CdX2 (X = Cl, Br, I) hydrothermally, resulting in three coordination architectures, namely [CdI2(L1)]n (1), [CdBr2(L2)]n (2), and Cd2Cl4(L3)2 (3) [L1 = 1,3-bis(5,6- dimethylbenzimidazole)propane, L2 = 1,5-bis(5,6-dimethylbenzimidazole)pentane, L3 = 1,6- bis(5,6-dimethylbenzimidazole)hexane]. They have been characterized by elemental analyses, IR spectra, thermogravimetric (TG) analysis, and single-crystal X-ray diffraction. Complex 1displays a helical chain linked by the ligands L1, and a 2D supramolecular network is constructed through π-π stacking interactions; complex 2shows a helical chain structure with connections through two kinds of strong π-π stacking interactions into an intricate 3D supramolecular network; complex 3 contains dinuclear metallomacrocycles. The fluorescence properties of 1-3have been investigated in the solid state

Three cadmium(II) coordination polymers, [CdBr2(L1)] n (1), [CdI2(L2)] n (2), and Cd2Br4(L3)2 (3), where L1 = 1,3-bis(5,6-dimethylbenzimidazole)propane, L2 = 1,4-bis(5,6-dimethylbenzimidazole)butane, and L3 = 1,6-bis(5,6-dimethylbenzimidazole)hexane, have been synthesized by hydrothermal methods and characterized by elemental analyses, IR spectra, TGA, PXRD, and X-ray crystallographic diffraction. Complex 1 contains a 1-D helical chain in which CdBr2 units are linked by L1. For 2, each CdI2 is connected by two different conformations of L2 to form a 1-D zigzag chain. For 3, each CdBr2 is linked by L3 bridges to afford a binuclear structure. These results indicate that the spacer length of the ligands play important roles in assembly of Cd(II) coordination polymers. Thermogravimetric analyses and solid-state luminescent properties of the complexes have also been investigated.

Compounds [CdLCl2] n (1) and {[Cd(L)2(ClO4)]·ClO4} n (2), where L = 1,3-bis(5,6-dimethylbenzimidazol-1-ylmethyl)benzene, have been synthesized by hydrothermal method, and characterized by element analysis, IR spectra, Powder XRD, and X-ray crystallographic diffraction. Cd(II) in 1 and 2 are both trigonal bipyramidal. Different cadmium salts of chloride and perchlorate lead to different configurations of [Cd2L2]2+, trans-form in 1 but trans and cis-forms in 2. The 1-D beaded chains of 1 are further linked to generate a 3-D supramolecular architecture by strong π–π stacking interactions as well as intermolecular C–H ··· Cl hydrogen bonds. In 2, the 1-D beaded chains are further assembled by intermolecular C–H ··· O hydrogen bonds to form a 2-D layer. Solid-state fluorescent properties of 1 and 2 were investigated at room temperature.

A new mononuclear complex Mn(bbbi)2(H2O)4(ClO4)2·(bbbi)2·(H2O)2 1 (bbbi = 1,4-bis(benzimidazol-1-yl)-2-butene) is synthesized under hydrothermal conditions and characterized by IR spectroscopy, elemental analysis, and single crystal X-ray structural analysis. Crystal data for 1: triclinic, $$P\bar 1$$ , a = 8.8478(7) A, b = 15.0550(11) A, c = 16.4310(12) A, α = 108.657(7)°, β = 104.044(7)°, Γ = 99.317(7)°, V = 1942.2(3) A3, Z = 1, final R = 0.0621. Each manganese atom is octahedrally coordinated by four aqua ligands and two nitrogen atoms of two distinct bbbi ligands. The molecule is stabilized by hydrogen bonding and π…π interactions.

A novel copper(II) complex {[Cu(BIX)2(H2O)2](PhCOO)2} n (1) (BIX = 1,4-bis(imidazole-1-methyl))-benzene) is synthesized and characterized by elemental analysis, IR, TG, and single crystal X-ray diffraction. Complex 1 crystallizes in the triclinic crystal system with the P-1 space group, Z = 1, a = 9.465(2) A, b = 9.703(2) A, c = 12.060(2) A, α = 77.26(3)°, β = 70.37(3)°, γ = 67.14(3)°, and V = 956.1(3) A3. The crystal structural analysis of complex 1 shows that the copper center is six-coordinated in an elongated octahedral geometry by four N atoms from four different BIX and two O atoms from two water molecules; two neighboring Cu(II) cations are bridged by two BIX extending into an infinite 1D double chain structure.

Two novel zinc coordination polymers {[Zn(PhCOO)2(bmix)]}n 1 and {[Zn(ada)(bmix)]·(H2O)2}n 2 (bmix = 1,4-bis(2-methylimidazole-1-ylmethyl)benzene, H2ada = adipic acid), were obtained by the hydrothermal reactions of bmix and zinc acetate with two carboxylate anions, respectively. Structural analyses show that complex 1 possess a one-dimensional helix chain structure, 2 takes two-dimensional corrugated (4,4) layer motif. The structural differences of two complexes indicate that organic carboxylate anions play important roles in the formation of such zinc(II) coordination architectures.

A novel Cu(II) mixed-ligand complex, {[Cu(sq)(L)(H2O)]· 0.9H2O}n (1) (sq = squarate dianion, L = 5,5′-dimethyl-2,2′-bipyridine), has been synthesized and characterized by elemental analyses, infrared (IR), and X-ray single-crystal diffraction. In 1, each copper(II) ion has a five-coordinated environment with square pyramidal geometry. A one-dimensional (1D) chain structure of the complex is constructed by squarate in μ-1,2-bis(monodentate) coordination mode and further forms a two-dimensional (2D) framework via “metal chelate–metal chelate ring” π–π stacking interactions between the adjacent chains. This unexpected π–π stacking interaction provides structural evidence for the metalloaromaticity of the Cu(II)-(aromatic α,α′-diimines) chelate rings.

Two new cobalt(II) coordination polymers, namely [Co1.5(PhCOO)3(bbbm)1.5(H2O)] n (1) and [Co(chdc)(bbbm)] n (2) (bbbm = 1,1′-(1,4-butanediyl)bis-1H-benzimidazole, H2chdc = 1,4-cyclohexanedicarboxylic acid), have been synthesized and structurally characterized by single crystal X-ray diffraction. The cobalt(II) centers display different environments, with trigonal–bipyramidal and octahedral geometries in 1 and a tetrahedral geometry in 2. The 1D linear chains of complex 1 and ladder-like chains of complex 2 are bridged by bbbm in bis-monodentate coordination mode; the variation of the carboxylate co-ligand effectively tunes the resulting framework architecture. The degradation of methyl orange in a photochemical Fenton-like process using complexes 1 and 2 as catalysts was investigated.

ZrO2 interface was designed to block the reaction between SiO2 and Y2O3 in SiO2@Y2O3:Eu coreshell structure phosphor. SiO2@ZrO2@Y2O3:Eu core-multi-shell phosphors were successfully synthesized by combing an LBL method with a Sol-gel process. Based on electron microscopy, X-ray diffraction, and spectroscopy experiments, compelling evidence for the formation of the Y2O3:Eu outer shell on ZrO2 were presented. The presence of ZrO2 layer on SiO2 core can block the reaction of SiO2 core and Y2O3 shell effectively. By this kind of structure, the reaction temperature of the SiO2 core and Y2O3 shell in the SiO2@Y2O3:Eu core-shell structure phosphor can be increased about 200-300 degrees C and the luminescent intensity of this structure phosphor can be improved obviously. Under the excitation of ultraviolet (254 nm), the Eu3+ ion mainly shows its characteristic red (611 nm, 5D0-7F2) emissions in the core-multi-shell particles from Y2O3:Eu3+ shells. The emission intensity of Eu3+ ions can be tuned by the annealing temperatures, the number of coating times, and the thickness of ZrO2 interface, respectively.

Eu2+ doped MgAl2O4–SrAl2O4–BaAl2O4 ternary phosphors were systematically studied by a sol–gel based combinatorial chemistry approach. The photoluminescence properties were optimized by chemically tuning of the compositions and a green phosphor and a blue one, with their compositions of Mg0.350Sr0.500Ba0.125Al2O4:Eu2+0.025 and Mg0.855Sr0.100Ba0.025Al2O4:Eu2+0.020 each were identified. The luminescent intensity of the green phosphor Mg0.350Sr0.500Ba0.125Al2O4:Eu2+0.025 was about 2.5 times to that of SrAl2O4:Eu2+0.015. For the blue one, Mg0.855Sr0.100Ba0.025Al2O4:Eu2+0.020, the luminescent intensity was about 19 times to that of MgAl2O4:Eu2+0.015. The quenching temperatures of Mg0.350Sr0.500Ba0.125Al2O4:Eu2+0.025 (green) and Mg0.855Sr0.100Ba0.025Al2O4:Eu2+0.020 (blue) were high enough for application in LEDs. In addition, they had very good excitation characteristics in the UV region as confirmed by the excitation spectra. We propose these two materials could be used as potential green and blue phosphors. More importantly, our sol–gel based combinatorial chemistry approach could be further applied to optimize the other phosphors systems.

Intense red phosphors, AgGd 1− x Eu x (W 1− y Mo y ) 2 O 8 ( x =0.0–1.0, y =0.0–1.0), have been synthesized through traditional solid-state reaction and characterized by X-ray diffraction (XRD) and photoluminescence (PL). XRD results reveal that AgGd 1− x Eu x W 2 O 8 synthesized at 1000 °C has a tetragonal crystal structure, which is named as high temperature phase (HTP) AgGdW 2 O 8 . All phosphors compositions with Eu 3+ show red and green emission on excitation either in the charge-transfer or Eu 3+ levels. Analysis of the emission spectra with different Eu 3+ concentrations reveal that the optimum dopant concentration for Eu 3+ is x =0.6 in the HTP AgGd 1− x Eu x W 2 O 8 ( x =0.0–1.0). Studies on the AgGd 0.4 Eu 0.6 (W 1− y Mo y ) 2 O 8 ( y =0.0–1.0) and AgGd 1− x Eu x (W 0.7 Mo 0.3 ) 2 O 8 ( x =0.0–1.0) show that the emission intensity is maximum for compositions with y =0.3 and x =0.5, respectively, and a decrease in emission intensity is observed for higher y or x values. The Mo 6+ and Eu 3+ co-doped AgGd(WO 4 ) 2 phosphors show higher emission intensity in comparison with the singly Eu 3+ -doped AgGd(WO 4 ) 2 in UV region. The intense emission of the tungstate/molybdate phosphors under 394 and 465 nm excitations, respectively, suggests that these materials are promising candidates as red-emitting phosphors for near-UV/blue GaN-based white LED for white light generation.

Three new complexes, [Ni2(dpc)2(L1)2(H2O)2] · 4H2O (1), [Ni(dpc)(L2)1.5] n (2), and {[Ni(dpc)(L3)1.5] · 2H2O} n (3), where H2dpc = dipicolinic acid, L1 = 1,4-bis(2-methylimidazol-1-yl)butane, L2 = 4,4′-bis(2-methylimidazol-1-ylmethyl)biphenyl, and L3 = 1,4-bis(benzimidazol-1-yl)-2-butylene, have been synthesized by hydrothermal methods and characterized by elemental analyses, infrared spectra, thermogravimetric analysis, and X-ray crystallography. The common structural characteristic of the three complexes is that the Ni2+ is coordinated by tridentate dipicolinate through nitrogen of pyridine and oxygen of carboxylate, serving as a terminal ligand. In 1, two L1 link two [Ni(dpc)(H2O)] units to a discrete binuclear metallomacrocycle with a 22-membered ring, which is assembled through multiple O–H ··· O hydrogen bonds to form a 3-D supramolecular framework. Complex 2 exhibits a 1-D ladder-like chain structure constructed by cis/trans-conformation L2 linking metal centers; 3 displays a 2-D (6,3) topology, be...

We prepared CaTiO3 by solid state reactions as a model for Ti-based microwave dielectric ceramics to investigate the influence of thermal treatment on conductivity and microwave dielectric loss. The intrinsic defect concentrations of CaTiO3 may be modified by air-quenching, air-annealing and thermal treatment in various atmospheres such as O2, Ar and air. CaTiO3 has p-type conductance implying that calcium vacancy V Ca × may be the dominant defect. The variation in defect concentration influences the low frequency conductivity but not the microwave dielectric loss. The V Ca × concentration in the air-quenched sample was found to be lower than that in the air-annealed one. However, the former showed ∼8% deterioration and the latter showed a 14% improvement in the Q × f value. The data, therefore, suggests that other factors such as thermally induced strain rather than intrinsic defects may influence the microwave dielectric loss.

This work describes a simple route to synthesize high temperature phase (X2) Y 2 SiO 5 superstructures assembled with nanoplates and particles. Two different novel morphologies, sphere-like superstructures assembled by plates and particles, were obtained by controlling the ratio of added salts as flux. The samples were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) technologies. The mixture of 3 wt.% AlF 3 -5 wt.% NaCl or 2 wt.% BaCl 2 -5 wt.% NaCl were found to be important for the generation of X2-Y 2 SiO 5 superstructures. Luminescent properties of the Ce 3+ doped Y 2 SiO 5 samples were also investigated. The fluxes played an important role in this method on phase transformation and improving luminescent intensity.

Ce doped yttrium aluminium garnet (YAG:Ce) was synthesized by LiF assisted sol–gel combustion method. The thermal behavior, composition, and microstructure feature of the precursor were studied by TG/DTA, XRD, PL, and SEM. The using of LiF in the sol–gel combustion process was helpful to decrease the sintering temperature about 200 °C. The X-ray diffraction patterns of the powder sintered at 540 °C were identical with the stoichiometric YAG composition, which was the lowest temperature reported for the synthesis of crystalline and single phase YAG. The PL intensity of the particles was found to be affected by the content of LiF and this phenomenon was thought to be related to the change of phase composition with the increase of flux.

Stabled hexagonal phase Sr 1− x Ba x Al 2 O 4 :Eu 2+ ( x =0.37–0.70) was prepared by solid-state method. Result revealed that the structure behavior of the SrAl 2 O 4 :Eu 2+ calcined at 1350 °C in a reducing atmosphere for 5 h strongly depended on the Ba 2+ concentration. With increasing Ba 2+ concentration, a characteristic hexagonal phase can be observed. When 37–70% of the strontium is replaced by barium, the structure of the prepared sample is pure hexagonal. Photoluminescence and excitation spectra of the samples with different x and doped with 2% Eu 2+ were investigated. Changes in the emission spectra were observed in the two different phases. The green emission at 505 nm from Eu 2+ was found to be quite strong in the hexagonal phase. The intensity and peak position of the green luminescence from Eu 2+ changed with increasing content of Ba 2+ . The strongest green emission was obtained from Sr 0.61 Ba 0.37 Al 2 O 4 :Eu 2+ . The decay characteristics of Sr 1− x Ba x Al 2 O 4 :Eu 2+ ( x =0.37–0.70) showed that the life times also varied with the value of x . Furthermore, the emission colors and decay times varying with x could be ascribed to the variation of crystal lattice.

Rare earth elements La3+ and Gd3+ doped (Y0.995Ce0.005)2SiO5 phosphors were prepared using the MS&Sol-gel method. The effect of the dopants on the structure and luminescent properties of the samples were analyzed. XRD patterns of the samples indicated that the phase transition temperature from the low temperature phase (X1) to the high temperature phase (X2) of Y2SiO5 increased with the doping concentration of La3+ and Gd3+. After annealing at high temperature for a long time, La3+ and Gd3+ doped X2-(Y0.995Ce0.005)2SiO5 were obtained, and the photo luminescent spectra was similar to that of the samples prepared by solid state method. Both PL and CL intensities of La3+ and Gd3+ doped X2-(Y0.995Ce0.005)2SiO5 prepared by MS&Sol-gel method were higher than that of the samples prepared by solid state method. La3+ and Gd3+ doping were useful in increasing the luminescent intensities of X2-(Y0.995Ce0.005)2SiO5. SEM showed that the particle size, dispersion degree, and particle shape of X2-(Y0.995Ce0.005)2SiO5 were also improved by the doping of La3+ and Gd3+.

Al3+/Mg2+ doped Y2O3:Eu phosphor was synthesized by the glycine-nitrate solution combustion method. In contrast to Y2O3:Eu which showed an irregular shape of agglomerated particles (the mean particle size >10 μm), the morphology of Al3+/Mg2+ doped Y2O3:Eu crystals was quite regular. Al3+/Mg2+ substituting Y3+ in Y2O3:Eu resulted in an obvious decrease of the particle size. Meanwhile, higher the Al3+/Mg2+ concentration, smaller the particle size. In particular, the introduction of Al3+ ion into Y2O3 lattice induced a remarkable increase of PL and CL intensity. While, for Mg2+ doped Y2O3:Eu samples, their PL and CL intensities decreased. The reason that causes the variation of PL and CL properties for Al3+ and Mg2+ doped Y2O3:Eu crystals was concluded to be related to sites of Al3+ and Mg2+ ions inclined to take and the difference of ion charge.

Systematic studies on CL and PL for rare earths (Sc3+, La3+, Gd3+ and Lu3+) doped Y2SiO5:Ce,Tb phosphor were performed and the formula (Y0.965−xRxTb0.03Ce0.005)2SiO5 (R = Sc, La, Gd and Lu) was applied to represent the compositions of the samples. Sensitizing influence of Ce3+ on Tb3+ can only be observed with the excitation of cathode rays and 355 nm UV. For the La3+ doped system, the PL intensity increased nearly 30% at x = 0.03; and for the Lu3+ doped system, the intensity increased about 20% at x = 0.20. Whereas doping of the Gd3+ and the Sc3+ reduced the intensity: at x = 0.3, the PL intensity decreased 10% for the Gd3+ doped system and about 25% for Sc3+. CL measurements showed that except the Sc3+, other rare earths doping improved the intensities: the La3+ doping made the intensity enhancement of about 10% at x = 0.03; the Gd3+ 35% at x = 0.1–0.3 and Lu3+ 25% at x = 0.1–0.2. For the Sc3+ doped samples, the CL intensity decreased about 25% at x = 0.2. The energy transfer processes were discussed for the Gd3+ doped samples. Two transfer processes from the Gd3+ to the Tb3+ were proposed: Gd3+ → Tb3+ and Gd3+ → Ce3+ → Tb3+.

Gd 3+ -doped (Y 0.995 Ce 0.005 ) 2 SiO 5 powder was synthesized by solid-state reaction. Morphology of (Y 0.995 Ce 0.005 ) 2 SiO 5 particles changed from an irregular shape to a regular shape of bottle-neck with the doping of Gd 3+ . Gd 3+ substituting Y 3+ in (Y 0.995 Ce 0.005 ) 2 SiO 5 resulted in obvious particle size reduction. The minimum degree of particle size became larger with increasing Gd 3+ content; at the same time, the particle surface became smoother. XPS measurements indicated that Gd 3+ inclined to locate at positions near particle surface. PL intensity of (Y 0.995 Ce 0.005 ) 2 SiO 5 decreased with the doping of Gd 3+ ; however, CL intensity increased. The mechanism of the relative intensity change was discussed. Also, particle shape of (Y 0.995 Ce 0.005 ) 2 SiO 5 did not change when other rare earths such as La 3+ , Sc 3+ and Lu 3+ were doped in.

High brightness Y 2 SiO 5 :Ce phosphor powders with spherical shape and fine size were synthesized by melting salt assisted sol–gel method (MS&Sol–Gel). Commercial tetraethyl orthosilicate was used as the silica source and rare earth oxides were used as rare earth source. The prepared Y 2 SiO 5 :Ce powders were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), laser particle sizer, and fluorescentometer techniques. Y 2 SiO 5 :Ce powders were obtained at significantly lower temperature than that by conventional techniques. When sintered at 1200 °C for 2 h with 5 wt.% LiF and 2 wt.% KH 2 PO 4 as fluxes, particles with spherical shape and narrow particle distribution could be obtained. Moreover, the grain size of the powders prepared through this process was in the range of 2–7 μm, strongly depending on the thermal treatments and the species of fluxes. PL intensity of the prepared Y 2 SiO 5 :Ce phosphor using 5 wt.% LiF and 2 wt.% KH 2 PO 4 as fluxes was similar to that of commercial product.

In order to reduce the risk of enrichment of polycyclic aromatic hydrocarbons (PAHs) in crops, reduce the potential hazards of food-sourced PAHs to human and increase the agricultural safety of PAHs contaminated soils, the bio-augmented removal of polycyclic aromatic hydrocarbons (PAHs) was investigated through in situ remediation by introducing Rhodobacter sphaeroides (RS) into the agricultural soil contaminated by PAHs. The 50-times diluted RS was sprayed on leaf surface (in area B) or irrigated to roots (in area D). The treatment of spraying water of the equal amount was taken as the control (A) and the wheat field without any treatment as the blank (CK). Treatments were conducted since wheat seeding. Soil and wheat samples were collected in the mature period to analyze the changes of community structure of the soil microorganisms and the concentration of PAHs in soils and investigate the strengthening and restoration effects of RS on PAHs contaminated soils. Compared to the CK Area, the areas B and D revealed that the variation ratio of phospholipid fatty acids (PLFAs) that were the biomarker of soil microorganisms was 29.6%, and the ratio of total PAHs removed was increased 1.59 times and 1.68 times, respectively. The dry weight of wheat grain of 50 spikes was increased by 8.95% and 12.5%, respectively, and the enrichment factor of total PAHs was decreased by 58.9% and 62.2% respectively in the wheat grains. All the results suggested that RS reduced enrichment of PAHs in wheat grains and increased wheat yield, which had great exploitation and utilization potentiality in repairing and improving the agricultural safety of the soils contaminated with PHAs.

Infrared-to-visible up-conversion luminescence (UCL) of RE3+ singly-doped and RE3+/Yb3+ co-doped CaIn2O4 (RE=Tm, Pr and Nd) phosphors were investigated under 980 nm excitation. The energy transfer from Yb3+ to RE3+ plays an important role in the UC process and the introduction of Yb3+ significantly enhances the UCL intensities of CaIn2O4: RE3+. The energy level diagrams and the possible UCL mechanisms of CaIn2O4: RE3+, Yb3+ (RE=Tm, Pr and Nd) were proposed based on the results of power dependence of the UCL intensities.

The phase relationships of the In2O3−TiO2−CaO and In2O3−TiO2−SrO systems have been studied at 1350 °C in air. The In2O3−TiO2−CaO system contains a ternary compound Ti6In6CaO22 crystallizing in an incommensurate structure. The In2O3−TiO2−SrO system, on the other hand, is a simple ternary phase diagram without any ternary phases. The structure of Ti6In6CaO22 can be expressed by an incommensurate composite model that consists of two subsystems: the first subsystem, containing the InO6 octahedral layer and the Ti atoms in the TiOx layer, is rather rigid and can be reasonably represented with the averaged structure within the main lattice, a = 5.951(1) A, b1 = 3.422(1) A, c = 6.352(1) A, and β = 108.32(1)°; the second subsystem, consisting of only the O2 atoms in the TiOx layer, can be expressed with a smaller subcell, a = 5.951(1) A, b2 = 2.464(1) A, c = 6.352(1) A, and β = 108.32(1)°. The overall structure was refined in the superspace group C2/m(0β0)s0, β = q/b* = 0.389(1) by using the program, JANA2000. T...

To observe the effect of "Shuanggu Yitong" (Double-reinforcing and one-unblocking) needling [electroacupuncture (EA) of "Guanyuan" (CV 4), "Housanli" (ST 36), "Fenglong" (ST 40) and "Zhongwan" (CV 12)] on expression of hypothalamic phosphatidylinositol 3-kinase (PI 3 K) and p-PI 3 K proteins in insulin resistance rats.Sixty Wistar rats were randomized into normal control, model, EA prevention, EA, cerebrospinal fluid (CSF), and Wortmannin (PI 3 K antagonist) groups (n = 10 rats/group). Insulin resistance model was established by feeding the animal with high fat forage continuously for 8 weeks. For rats of the EA group, EA (2 Hz, 1 mA) was applied to ipsilateral "Housanli"(ST 36)-"Fenglong" (ST 40), and "Guanyuan" (CV 4)-"Zhongwan" (CV 12) for 15 min, once daily, 5 times a week and for 8 weeks, beginning after modeling. For rats of the EA prevention group, EA was conducted simultaneously with the modeling. For rats of the Wortmannin group and CSF group, cerebroventricular microinjection of Wortmannin (50 nmol/L, 3 mg/kg) or artificial CSF was given through an implanted steel cannel. Fasting plasma glucose (FPG) and fasting serum insulin (FINS) contents were assayed using glucose-tested instrument and ELISA respectively, insulin activity index (IAI) was calculated [IAI = Ln (1/FPG x FINS)], and the expres- sion of hypothalamic PI 3 K and p-PI 3 K proteins was detected by Western blot.In comparison with the normal control group, the body weight (BW), FPG and FINS contents at time-points of 8 and 16 weeks were considerably increased (P0.01), and IAI, hypothalamic PI 3 Kp 110 and p-PI 3 Kp 110 protein expression levels were obviously decreased in the model group (P0.01). Compared with the model group, the FPG and FINS contents at the 8th week after modeling in the EA prevention group, the BW and FPG levels at the 16th week in the EA prevention, EA and CSF groups, FINS levels at the 16th week in the EA prevention and EA groups were remarkably decreased (P0.05, P0.01), IAI, and hypothalamic PI 3 Kp 110 and p-PI 3 Kp 110 protein expression levels were significantly up-regulated in the EA prevention, EA and CSF groups (P0.05, P0.01). No significant differences were found among the EA prevention, EA and CSF groups, and between the model and Wortmannin groups in the BW, FPG, FINS, IAI and hypothalamic PI 3 Kp 110 and p-PI 3 Kp 110 expression levels (P0.05).EA intervention can reduce insulin resistance by suppressing the increase of body weight, blood glucose and insulin contents, and increasing hypothalamic PI 3 K expression levels in insulin resistance rats.

To explore the effect of long-term lead exposure on brain iron in aged rats.SPF female and male Sprague-Dawley rats were respectively randomly divided into three groups: control, low lead-exposed, high lead-exposed. Lead-exposed female rats drank 0.8g/L or 1.5g/L lead acetate solutions through pregnancy until weaning and then the pups received 0.3g/L or 0.9g/L lead acetate solution depending on their group. Control group rats drank deionized water throughout the experiment. At the postnatal 18 months, one pup for per group was given an ultra structural detection of hippocampus, and the other male pups were measured the lead and iron concentration of blood and brain by GE MR 3.0T MR scanner and ICP-AES.In comparing with control group, the lead concentrations of blood and brain in lead-exposed groups were significantly higher, and the iron contents of brain and cortex, hippocampus, thalamus were significantly higher in 0.9g/L lead-exposed group. Also, it was highly positively correlated between blood lead and iron of blood, cortex, hippocampus, thalamus, respectively. With the dose of lead-exposed increased, cytoplasm, nucleus, mitochondrial structure and synaptic structure had suffered vary degrees of damage from ultra structural detection of hippocampus, it could be observed early neuronal apoptosis.Lead induced neurodegenerative diseases might be related to iron overload which caused by lead exposure.

To observe the effects of Xuefu Zhuyu Decoction (XFZYD) on the angiogenesis and injury repair in the ischemic region.The ischemic hind limb rat model was established using Bletilla embolization. Endothelial progenitor cells (EPCs) were labeled with DAPI and injected into the model rats from the vena caudalis. Then rats were treated with different doses of XFZYD by gastrogavage. Blood was withdrawn. The granulation tissue and the muscle tissues from ischemic and necrotic portion were taken on the 3rd and 7th day of the medication. The samples were frozen and sliced to analyze the fluorescent expressions. The necrosis of each sample was observed by routine pathological section. The vessels number was counted. The serum NO levels were detected using nitrate reductase method. The macro-morphological observation of ischemic lower limbs were lasted for 30 days.After 3 and 7 days of medication, the fluorescence intensity of ischemic area and the number of granulation vessels were significantly more in the high dose XFZYD group than in the routine treatment group and the normal saline treatment groups. The aforesaid indices were significantly higher in the routine treatment group than in the normal saline treatment group after 7 days of medication. The serum NO concentrations were significantly lower in the normal saline group at other time points. On the 30th day of medication, the muscular atrophy of the ischemic hind limbs was the least significant in the high dose XFZYD group.XFZYD could improve the ischemic necrosis by improving the NO level, inducing the EPCs' migration to the ischemic region, and promoting the angiogenesis.

To observe the effect on EPCs function by Xuefu Zhuyu Decoction.After induced by serial concentrations of Xuefu Zhuyu Decoction-contained serum (XZDCS) and blank serum, EPCs proliferation, migration, adhesion and uptake function were detected by MTT, Boyden chamber, adhesion and uptake of ac-LDL respectively.Compared with the control group, 15% and 10% XZDCS could elevate the cell regeneration for 24 h and 48 h respectively. Both concentrations could improve the EPCs migration and adhesion for all 24, 48, 72 h and uptake of ac-LDL only 48 h. But 10% XZDCS could last effect on uptake of ac-LDL to 72 h and 5% XZDCS converted the inhibition of cell adhesion in the first 24 h to promotion in the next 48 - 72 h.Xuefu Zhuyu Decoction could induce EPCs differentiation into EC to angiogenesis by promoting its proliferation, migration, adhesion and uptake function.

To establish HPLC fingerprint of flavonoids and phenols of Dendrobium nobile.Phenomenex prodigy ODS(3) C18 column (250 mm x 4.6 mm, 5 microm) was used with a mixture of acetonitrile-0.1% acetic acid as the mobile phase in a gradient mode, the column temperature was 25 degrees C, the flow rate was 1.0 mL/min, and the detection wavelength was 254 nm.The flavonoids and phenols of Dendrobium nobile were well separated, and 10 fingerprint peaks in common were confirmed.This method is simple, accurate with good reproducibility, and can be used specifically for the quality control of Dendrobium nobile.

To observe the effect of Xuefu Zhuyu Decoction ()-containing serum (XFZYD-CS) on endothelial progenitor cell (EPC) tube formation in vitro.Mononuclear cells from rat bone marrow were prepared in a Ficoll density gradient centrifuge. EPCs were separated by the differential attachment method, and observed with inverted microscope for the effect of XFZYD-CS on EPC tube formation.After one day, EPCs exposed to the serum containing 5%, 10% and 15% XFZYD-CS formed typical tubes or vessel networks. The tube formation time was two days ahead of the control group and the size of most tubes in the serum groups was smaller than in the control group.XFZYD-CS could induce EPC angiogenesis and hasten tube formation, especially in capillary vessels. The study provides experimental evidence for the plausibility of Xuefu Zhuyu Decoction in the treatment of ischemic diseases.

To optimize the formulation and preparation method of multivesicular liposome of thymopentin and to investigate its pharmacokinetics in rats, the multivesicular liposome of thymopentin was prepared by double emulsification method and the formulation was optimized by orthogonal design. The release characteristics of thymopentin from multivesicular liposome in PBS (pH 7.4) and in plasma were investigated. The multivesicular liposome of thymopentin labeled with fluorescein isothiocyanate was prepared by double emulsification method. Its pharmacokinetics was evaluated following intramuscular injection in rats. The optimal formulation of multivesicular liposome of thymopentin were formulated with 7.5% glucose in aqueous phase and 2.25 mol x L(-1) triolein, 2.68 mol x L(-1) DPPG and 16.96 mol x L(-1) DOPC in organic phase. The entrapment efficiency of the multivesicular liposome of thymopentin was above 85% and the mean particle size was about 22 microm. The in vitro release of thymopentin from multivesicular liposome in PBS (pH 7.4) and in plasma was found to be in a sustained manner. The release curves were fitted to Higuchi equation. The pharmacokinetics following intramuscular injection of the multivesicular liposome of thymopentin labeled with fluorescein isothiocyanate in rats showed that the peak concentration of thymopentin was lower and elimination of it was slower significantly than that of thymopentin labeled with fluorescein isothiocyanate solution in the same dose. The plasma concentration of thymopentin maintained above quantitative limitation at 120 h after administration of multivesicular liposome of thymopentin. The optimized formulation and preparation technology of multivesicular liposome of thymopentin with higher entrapment efficiency are feasible with good reproducibility. Multivesicular liposome of thymopentin showed significant sustained-release property following intramuscular injection in rats.

In the title compound, C14H14N4, the center of the phenylene group is a crystallographic center of inversion. The compound is composed of three aromatic rings displaying a Z-like conformation. The dihedral angle between the pyrazole rings and the central phenyl ring is 83.84 (9)°.

Cathodoluminescent measurements were conducted to Eu 3+ , Tb 3+ , and Eu 3+ -Th 3+ pair-doped Zn 3 Ta 2 O 8 as well as undoped Zn 3 Ta 2 O 8 . Tb 3+ -doped samples mainly gave the characteristic emission of Tb 3+ with green color, while in Eu 3+ -doped samples, the dominating emission was the blue band that was contributed by the host emission and Eu 2+ emission. For Eu 3+ and Tb 3+ codoped Zn 3 Ta 2 O 8 , the spectrum mainly consisted of the characteristic emissions of Tb 3+ and a strong blue emission; the emissions from Eu 3+ appeared very weak. The blue emission of Eu 2+ may be understood by using the reduction mechanism (Eu 3+ + e → Eu 2+ ), and the charge transfer mechanism (Eu 3+ + Tb 3+ → Eu 2+ + Tb 4+ ). For the Eu 3+ and Tb 3+ codoped samples, although the Eu 3+ emission was very weak, it still increased with Tb 3+ content, this was because the energy transfer from Tb 3+ to Eu 3+ also occurred.

Luminescent properties of Sc 3+ and La 3+ doped (Y 0.995 Ce 0.005 ) 2 SiO s phosphors were studied. In the Sc 3+ doped system (Y 0.995-x Sc x Ce 0.005 ) 2 SiO 5 , the solid solution extends to x = 0.65, but in the La 3+ doped system (Y 0.995-x, La x Ce 0.005 ) 2 SiO 5 , the solid solution range is not over the La 3+ content of x = 0.05. For La 3+ doped samples, the photoluminescence (PL) increases about 30% and cathodoluminescence (CL) increases about 10%. Additionally the color saturation is also improved with La 3+ doping. The mechanisms for these improvements are discussed. For the Sc 3+ doped samples, both PL and CL, clearly decrease. These phosphors may be useful in field emission displays TEED).

This paper reports a systematic investigation on photoluminescent (PL) properties of Eu 3+ and Tb 3+ -activated Zn 3 Ta 2 O 8 . The excitation spectrum of Zn 3 Ta 2 O 8 :Eu 3+ consists of the strong CTS absorption and week f-f transitions of Eu 3+ , while the excitation spectrum of Zn 3 Ta 2 O 8 :Tb 3+ is composed of the strong d-f transition and weak f-f transitions of Tb 3+ . The charge transfer state (CTS) band of Eu 3+ and the d-f peak of Tb 3+ slightly shift to lower energy with increase of dopant contents. Zn 3 Ta 2 O 8 :Eu 3+ exhibits red emission peaks around 610-620 nm, which is related to the transitions of 5 D 0 → 7 F 2 . The luminescence of Zn 3 Ta 2 O 8 :Tb 3+ is dominated by green emission peaks at 546 nm, which can be attributed to the transition of 3 D 4 → 7 F 5 . For Eu 3+ -Tb 3+ codoped Zn 3 Ta 2 O 8 , energy transfer process takes place and the resonant mechanism is proposed as the transfer mechanism which can be described as: 5 D 4 (Tb 3+ ) + 7 F 0 (Eu 3+ ) → 7 F 5 (Tb 3+ ) + 5 D 1 (Eu 3+ ). PL spectra and lifetime measurements support this mechanism. Due to the energy transfer. PL intensity of Eu 3+ emission increased about 40%.