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The CeO 2 nanoparticle-decorated graphene hybrid was prepared by hydro-thermal method and their application in electrochemical detection of heavy metal ions was investigated. It was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscopy (TEM). The electrochemical behavior of four heavy metal ions (cadmium(II), lead(II), copper(II), and mercury(II)) on the graphene/CeO 2 hybrid nanocomposite modified glassy carbon electrode (GCE) was investigated in acetate buffer solution by differential pulse anodic stripping voltammetric (DPASV). Compared with the bare GCE, the proposed electrode showed improved analytical performance characteristics in detecting heavy metal ions. By using DPASV method, it shows that the graphene/CeO 2 hybrid nanocomposite modified GCE could be used for tracing Cd 2 + , Pb 2 + , Cu 2 + , and Hg 2 + simultaneously and selectively. Under optimum conditions, we can detect Cd 2 + , Pb 2 + , Cu 2 + , and Hg 2 + simultaneously with high sensitivity in low concentration in the experiments. [ABSTRACT FROM AUTHOR]

We studied the radiation tolerance of amorphous silicon oxycarbide (SiOC) alloys by combining ion irradiation, X-ray diffraction (XRD) and transmission electron microscopy (TEM). The amorphous SiOC alloys thin films were grown via co-sputtering from SiO 2 and SiC (amorphous phase) targets either on a surface oxidized Si (100) substrate or on a sodium chloride substrate. By controlling the sputtering rate of each target, SiOC alloys with different compositions (1:2, 1:1, 2:1 ratios) were obtained. These alloys were irradiated by 100 keV He + ions at both room temperature and 600 °C with damage levels ranging from 1 to 20 displacements per atom (dpa). TEM characterization shows no sign of crystallization, void formation or segregation in all irradiated samples. Our findings suggest that SiOC alloys are a class of promising radiation-tolerant materials. [ABSTRACT FROM AUTHOR]

Based on orthogonal test design, the factors influencing the synthesis of methotrexate intercalated magnesium–aluminum layered double hydroxides (MTX/LDHs for short) by ion-exchange method, such as weight ratio of pristine LDHs to MTX ( R for short), exchange temperature, time and pH value were investigated. Of the four controllable independent variables, R had the strongest effect on the crystallinity and the drug-loading capacity and the optimum synthesis conditions considered from the crystallinity and the drug-loading capacity both pointed to the same values, i.e., R =2:1, pH=9.5, temperature of 80 °C and exchange time of 3 day. The XRD diffractions indicated that high MTX content was in favor of the formation of intercalated hybrids, while low content lead to the failure of it. TEM photos indicated that the intercalated hybrids all exhibited aggregated hexagonal plates. In order to improve the morphology, two different states of pristine LDHs, i.e., powder and colloid, were chosen to prepare MTX/LDHs hybrids and the results indicated that colloid state of pristine was advantageous to obtain regular particles. The study also revealed that the properties of hybrids obtained at optimum conditions by ion-exchange were superior to that obtained from standard methods, such as co-precipitation method. [ABSTRACT FROM AUTHOR]

A series of methotrexatum intercalated layered double hydroxide (MTX/LDH for short) hybrids have been synthesized by a mechanochemical–hydrothermal method, the statistical experiments are planned and conducted to find out the critical factor influencing the physicochemical properties. Four variables, i.e., addition of NaOH solution, grinding duration, hydrothermal temperature and time, are chosen to play as the examined factors in the orthogonal design. Furthermore, three respective levels, i.e., high, medium and low levels, are conducted in the design. The resulting hybrids are then characterized by X-ray diffraction (XRD) patterns, transmission electron microscope (TEM) graphs and Zeta potentials. XRD diffractions indicate that MTX anions have been successfully intercalated into LDH interlayers and the amount of NaOH solution can change the gallery height greatly. The information from TEM graphs and Zeta potentials state that the increase of alkali solution gives rise to regular morphology and the increase of Zeta potentials. As a result of the statistical analysis, addition of alkali solution is the major factor affecting the morphology and drug-loading capacity. At last, the mechanism of particle growth is explored emphatically, and the anticancer efficacy of some MTX/LDH hybrids is estimated by MTT assay on A549 cells as well. [ABSTRACT FROM AUTHOR]

In this paper, the intercalation of methotrexatum (MTX) into layered double hydroxides (LDHs) via an exfoliation-reassembly process was reported and the resulting hybrids were then characterized by X-ray diffraction (XRD) patterns, Fourier transform infrared (FTIR) spectroscopy and atomic force microscopy (AFM) patterns etc. In the synthesis procedure, LDHs particles were firstly delaminated into well-dispersed 2D nanosheets in formamide by ultrasonic treatment at room temperature, and then the resulting LDH nanosheets were reassembled in MTX solution to form MTX intercalated LDH (MTX/LDHs) hybrids. AFM images showed that during the exfoliation process a large part of LDHs particles were delaminated into single and double brucite layers. XRD patterns and FTIR investigations manifested the successful intercalation of MTX anions into LDHs interlayers for the final samples. It was also found out that the drug-loading capacity of the hybrids increased with the concentrations of MTX solutions, while the morphology became even aggregated. At last, the cell cytotoxicity of the hybrids was estimated by MTT assays on the human lung cancer cells (A549), and the results stated that MTX/LDHs hybrids had effective suppress role on the proliferation of cancer cells. [ABSTRACT FROM AUTHOR]

Abstract: A new compound, ortho-C6H4F[CH(NHC6H4OMe-2)2], 1, was obtained with ortho-flurobenzaldehyde and 2-methoxyaniline as the starting materials. Compound 1 was readily converted into ortho-C6H4(2-OMeC6H4)(CH NC6H4OMe-2) 2 after treatment with 1 equiv of n-BuLi. Treatment of compound 2 with 1.5 equiv of ZnEt 2 afforded the trinuclear zinc complex 3 by alkyl elimination and alkylation of the imino group of the ligand. The molecular structures of two new organic compounds and of the trinuclear zinc complex were determined by single-crystal X-ray diffraction. The dianionic ONNO tetradentate ligands derived from compound 2 coordinate to zinc ions in four to five coordination modes, forming distorted tetrahedral and trigonal–bipyramidal geometry around three metal centers. [Copyright &y& Elsevier]

Abstract: Two-phase (Ce0.9Gd0.1O1.95)0.5/(Zr0.92Y0.08O1.96)0.5 (GDC/YSZ) nanocomposite thin films with vertically aligned structure are grown as the electrolyte for thin film solid oxide fuel cells (TFSOFCs). X-ray diffraction (XRD) and transmission electron microscopy (TEM) results confirm that GDC and YSZ grow as separated, high crystallinity nanocolumns with tunable column width on both single crystal and polycrystalline anode substrates. Impedance measurements demonstrate ∼50% enhancement in ionic conductivity compared to pure single-crystal-like GDC thin film. The enhanced properties in the GDC/YSZ vertically aligned nanocomposite (VAN) system may be attributed to two-phase strain coupling and the fast ionic transport rate along the vertical interfaces. The VAN is applied in thin film SOFC as a part of the electrolyte in the single cells. The overall power density increases more than 40% compared with that of the cells without VAN electrolyte. This work demonstrates the first VAN nanostructured electrolyte with the essential vertical ion-transport channels. The new VAN electrolyte provides superior out-of-plane ionic conductivity compared to those single phase electrolytes as well as the nanolayered electrolytes. [Copyright &y& Elsevier]

An acetal-linked porous organic polymer ( APOP ) was synthesized by the p -toluenesulfonic acid-catalyzed acetalization reaction of 1,4-phthalaldehyde with 1,3,5-tris(3- tert -butyl-4-hydroxy-5-hydroxymethyl)phenyl benzene. The obtained polymer possessed amorphous structure and also exhibited excellent thermal stability, as revealed by powder X-ray diffraction (PXRD) and thermogravimetric analysis (TGA). The APOP were further characterized by solid-state 13 C nuclear magnetic resonance (NMR), fourier transform infrared (FT-IR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The APOP exhibited a Brunauer-Emmett-Teller (BET) surface area of 490 m 2  g −1 with pore size distribution in the range of mesopores and the pore volume of 0.435 cm 3  g −1 . The resulting polymer displayed the CO 2 uptake capacity of 85.7 mg g −1 at 273 K and 53.7 mg g −1 at 298 K (1 bar). Furthermore, the iodine adsorption performance of the APOP was also investigated, and it was found that the iodine uptake capacity could reach up to 220 wt%. These results were demonstrated that the APOP should be promising candidate for CO 2 and iodine uptake. [ABSTRACT FROM AUTHOR]

Abstract: The Bi2O3/Bi2WO6 heterojunction photocatalysts were prepared by a two-step solvothermal process using Bi(NO3)3-ethylene glycol solution as Bi source. The catalysts were characterized by X-ray diffraction, scanning and transmission electron microscopy, X-ray photoelectron spectroscopy, and UV–vis diffuse reflection spectroscopy. The heterostructure catalysts are composed of Bi2O3 nanoparticles as modifier and 3D Bi2WO6 microspheres as substrate. Bi2O3 nanoparticles with diameters of about 10–15nm are tightly grown on the lateral surface of the Bi2WO6 microspheres. The hierarchical Bi2O3/Bi2WO6 microspheres exhibit higher photocatalytic activity than the single phase Bi2WO6 or Bi2O3 for the degradation of rhodamine B under visible light illumination (λ>420nm). The enhancement of the photocatalytic activity of the Bi2O3/Bi2WO6 heterojunction catalysts can be ascribed to their improved light absorption property and the reduced recombination of the photoexcited electrons and holes during the photocatalytic reaction. The effect of loading amount of Bi2O3 on the catalytic performance of the heterojunction catalysts was also investigated and the optimal content of Bi2O3 is 3wt%. The Bi2O3/Bi2WO6 heterojunction photocatalysts are essentially stable during the photocatalytic process. [Copyright &y& Elsevier]

Two mixed-ligand Cu(II) complexes, [Cu(L 1 )(L 2 )](ClO 4 ) 2 ·H 2 O ( 1 ) and [Cu(L 1 )(L 3 )](ClO 4 ) 2 ·H 2 O·CH 3 OH ( 2 ) (L 1 = N , N ′-bis(2-pyridylmethyl)amantadine, L 2 = 5,5′-dimethy-2,2′-bipyridine, and L 3 = 1,10-phenanthroline), were synthesized and characterized by elemental analysis, UV–Vis, infrared spectra and single crystal X-ray diffraction. Copper ions in 1 and 2 behave the slightly distorted tetragonal pyramid configuration provided by CuN5 coordination set. Both complexes exhibit the quasi -reversible Cu(II)/Cu(I) one-electron redox waves determined by the cyclic voltammetry. Moreover, the frontier molecular orbital energies were obtained by DFT calculations with B3LYP method at LanL2DZ basis. Furthermore, by using NBT assay at pH 7.8, the superoxide dismutase (SOD)-like activity (IC 50 ) of 1 and 2 were measured to be 0.167 and 0.242 μM, respectively. The difference in SOD-like activities of two complexes could be ascribed to the rigidity of the auxiliary ligands. [ABSTRACT FROM AUTHOR]

Abstract: Two new Zn(II) complexes of, 2,6-bis[1-(2,6-diisopropylphenylimino)ethyl]pyridine (L 1 ), 2,6-bis[1-(2,6-dimethylphenylimino)ethyl]pyridine (L 2 ) were synthesized. These two complexes have the formulas Zn(L1)Cl2 (1) and Zn(L2)Cl2·CH3CN (2), respectively. Crystal structures of complexes 1 and 2 were determined by single-crystal X-ray diffraction. Crystallographic studies on 1 and 2 reveal both complexes to be five-coordinate with geometries that can be best described as distorted trigonal bipyramidal. Complexes 1 and 2 have blue luminescence at room temperature in solution and the solid state. The blue luminescence of the complexes is due to π* →π transition centered on the ligands. The Zn(II) centers play a key role in enhancing fluorescent emission of the ligands. [Copyright &y& Elsevier]