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A salt-assistant stearic acid method (SAM) capable of forming ultrafine K 4 Ce 2 Nb 10 O 30 products was described. XRD pattern revealed that tetragonal K 4 Ce 2 Nb 10 O 30 products could be obtained by heat treatment at 900 °C for 2 h. Transmission electron microscopy (TEM) observations indicated the introduction of KCl could lead to the formation of rod-like K 4 Ce 2 Nb 10 O 30 products. The species of salts played a crucial role in fine tuning the shapes and sizes of K 4 Ce 2 Nb 10 O 30 products. Furthermore, the K 4 Ce 2 Nb 10 O 30 prepared by salt-assistant SAM had considerable activity under visible light irradiation.

Superfine Sr 2 CeO 4 :RE 3+ (RE=Eu, Sm) phosphors were synthesized at relatively low temperature by a modified sol-gel method using nitrates as raw materials, ethylenediaminetetraacetic acid (EDTA) as complexing agent. Single phase phosphors could be obtained at calcination temperature above 800 °C and pH value higher than 6.4 of initial solution. The as-prepared powders consisted of uniform crotch-like grains. The preparation process was monitored by thermogravimetric and differential thermal analysis (TG-DTA) and Raman spectra. The obtained products were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS) and photoluminescence. Photoluminescence study indicated that strong energy transfer occurred between Eu 3+ /Sm 3+ and host. The Sr 2 CeO 4 :RE 3+ emission could be tuned from blue to white and red light by varying the concentration of RE 3+ . The strong emission and controllable light color are suitable for applications in advanced lighting and displaying fields.

In situ catalytic thermal decomposition of ammonium perchlorate (AP) was investigated over CoC 2 O 4 . The catalytic activity measurements were carried out by DSC and TG-MS. The results show that the new ecological nano-cobalt oxides exhibit better catalytic performance in thermal decomposition of AP. Adding 2% of CoC 2 O 4 to AP decreases the decomposition temperature by 104 °C and increases the heat of decomposition from 655 J/g to1469 J/g. Products of thermal decomposition of AP are H 2 O, NH 3 , O 2 , HCl, Cl 2 , NO, N 2 O, and NO 2 . The oxidation of adsorbed ammonia by cobalt oxides via the superoxide active centers takes place on the surface of cobalt oxide. The presence of oxygen can accelerate the oxidation thermal decomposition process of AP, with a clear increase in DSC heat release.

A facile approach to preparing well-dispersed nanocrystals of BaCeO3 was developed by a combination of solvothermal and annealing processes. The precursor consisted of amorphous BaCO3 and CeO2, and the conversion of the precursor to crystalline BaCeO3 nanocrystals occurred upon heat treatment at a relatively low temperature. The as-processed BaCeO3 had an orthorhombic structure and the average size of such crystals was approximately 80 nm. The obtained products were characterized by Fourier Transform Infrared (FT-IR), X-Ray Diffraction (XRD), Laser Raman Spectroscopy (LRS), Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectrometry (EDS), and Transmission Electron Microscopy (TEM). This preparation process could also be used to synthesize doped barium cerate complex oxides BaCe0.95M0.05O3.δ (M=Y, Nd, Gd, and Sm).

A facile co-precipitation route for the synthesis of well-dispersed LaCoO3 nanocrystals was developed. The asprepared products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray spectrometer (EDX), and laser Raman spectroscopy (LRS). The results showed that modulating the growth parameters, such as the addition of surfactants as well as the adding manner of the precipitator had a significant effect on the overall shape and size of the obtained nanocrystals. The nanorods with the diameter of 20 nm and spherical LaCoO3 nanocrystals with the size of about 25 nm could be obtained at a relatively low calcining temperature of 600 °C. Furthermore, the Raman properties of LaCoO3 products obtained at different calcining temperatures were investigated.

Melamine resin microcapsules containing CI Disperse Blue 56 were prepared by in situ polymerisation. The microcapsules were characterised by their thermal properties and morphology, such as particle size and particle size distribution. The dyeing behaviour of the microcapsules on nylon 6.6 was evaluated. The microencapsulated dye exhibited good build-up, levelness and fastness properties. It has been demonstrated that microencapsulated disperse dye can be used to replace commercial disperse dyes in dyeing polyamide fabric without dyeing additives, and the resulting effluent can be easily recycled after filtration.

Two new copper(II) complexes were synthesized from 2-hydroxyl-4-methoxyacetophone with R-NH–CH2–CH2–CH2–NH2 (for complex 1, R = H; complex 2, R = C6H5–CH2–) in the presence of Cu2+. Crystals of 1 were monoclinic, space group P21/n, with a = 12.6408(10) A, b = 7.4063(6) A, c = 16.8863(14) A and β = 93.3590(10)°, complex 2 crystals were triclinic, space group P with a = 7.561(3) A, b = 10.680(4) A, c = 13.868(5) A and α = 97.389(6)°, β = 95.240(6)°, γ = 101.206(6)°. Both Cu(II) atoms were four-coordinate with distorted square-planar geometry. The toxicity of 1 and 2 were evaluated by testing antimicrobial activity against bacterial strands.

Two new copper(II) complexes were synthesized by reaction of N-(3-aminopropyl)benzylamine (L1: apba, for complex 1) and N-salicylidene-apba (L2: for complex 2) with Cu2+. Crystals of complex 1 were orthorhombic, space group pccn, with a = 15.2149(10), b = 25.0071(16), c = 7.6280(5) A and α = β = γ = 90°. Complex 2 crystals were monoclinic, space group P21/c, with a = 8.688(6), b = 12.812(9), c = 16.022(11) A and β = 99.241(10)°. Structures of the two complexes were centro-symmetric and both Cu(II) atoms were four coordinate with a distorted square-planar geometry. The toxicity of the complexes was evaluated by testing antimicrobial activity against bacterial strands.

A theoretical study of the polymerization reaction mechanism of maleic anhydride (MA) initiated by hydrate is presented. The reaction pathway has been studied with the density functional theory (DFT) method at the B3LYP/6-311G** level. The geometrical parameters of transition states (TS) are optimized; intrinsic reaction coordinate (IRC) calculations have also been performed to obtain further credible features. Frequency analyses of all the stationary points are calculated at the same basis sets. The total energies of all geometries are corrected at second-order Moller–Plesset (MP2)/6-311G**. Calculation results reveal that the reaction mechanism is attributable to anion polymerization. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006

Two compounds 2-benzoyl-N-phenyl-2-(1,2,4-triazol-1-yl)thioacetamide (1) and 2-(4-chlorobenzoyl)-N-phenyl- 2-(1,2,4-triazol-1-yl)thioacetamide (2) were synthesized from substituted acetophenone, triazole and phenyl isothiocyanate by several step reactions. The structure of compound 1 was determined by single-crystal X-ray diffraction analysis. It crystallizes in monoclinic system with space group P21/c, a=0.8806(2) nm, b=1.2097(2) nm,c=1.4809(3) nm, β=105.88°, Z=4, V=1.5173(6) nm3, Dc=1.411 Mg/m3, μ=0.22 mm-1, F(000)=672, finalR1=0.040 and Rw=0.103. There is obvious potentially weak CH···N intermolecular interaction in the crystal, which stabilizes the structure. The results of biological test show that the two compounds have antifungal and plant growth regulating activities.

A voltammetric study of the interaction of 5-(4-diethylamino-2-hydroxyphenylazo)-4-hydroxynaphthalene-2,7-disulfonic acid (beryllon III) with protein at the mercury electrode in Britton-Robinson (B-R) buffer solution is described in this paper. In pH 3.5 B-R buffer solution, beryllon III has a well-defined second order derivative linear sweep voltammetric reductive peak. After addition of human serum albumin (HSA) to beryllon III solution, the current value of reductive peak of beryllon III decreases while the peak potential does not shift and no new peaks appear. The electrochemical parameters such as the formal potential E°, the standard rate constant of the electrode reaction ks, the transfer coefficient α of beryllon III have no significant changes in the presence of HSA. So the binding interaction of beryllon III with protein forms an electrochemically non-active complex. The equilibrium constant for this super-molecular complex and the interaction mechanism are discussed carefully. On the basis of this interaction, a sensitive assay method for proteins, such as HSA, bovine serum albumin (BSA), egg albumin et al, is also established. The linear relationship between the decrease of the peak current and the concentration of the protein is in the range of 1.0–70.0 mg/L with the detection limit of 1.0 mg/L HSA. This method was further applied to determine the healthy human serum samples and the results are consistent with the Coomassie brilliant blue G-250 spectrophotometric assay.

A series of Ru(II) complexes have been synthesized, and their electronic spectra and NMR spectroscopy properties were characterized. the chemical shifts of aromatic protons of [Ru(bpy)3] (PF6)2, [Ru(phen)3](ClO4)2 and [Ru(bqdi)3](PF6) move downfield, but the resonance peaks of cis-Ru(bpy)2Cl2 shift upfield. Within the visible spectra of the ruthenium(II) complexes appear a relatively high oscillator strength which is referred to as the π(Ru)→∗ (ligands) transition.

Nano-materials can be used as filler for polymers. Thereby, the mechanical properties of the obtained materials can be obviously improved. In this paper, nanometre-sized TiO2 was used as filler for unsaturated polyester (UP) resin, and the effect of the amount of the filler on the mechanical properties of this material was discussed.