Flame retardation and char formation mechanism of intumescent flame retarded polypropylene composites containing melamine phosphate and pentaerythritol phosphate

The flame retardation of polypropylene (PP) composites containing melamine phosphate (MP) and pentaerythritol phosphate (PEPA) was characterized by cone calorimeter. The formation mechanism of the char obtained from the combustion of the composites after cone calorimeter testing was studied by scanning electron microscopy (SEM), Fourier transform infrared spectra (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and Raman diffusion. Results demonstrated that the PP composite containing MP and PEPA showed good flame retardancy. It had been found that the intumescent char could be principally divided into three parts, i.e. outer, middle and inner char layer, according to their different structures and components.     

Synthesis and Luminescent Property of Polycarbazole/Polyhedral Oligomeric Silsesquioxane Nanocomposites

Polyvinylcarbazole（PVK） composites containing organic-inorganic hybrid polyhedral oligomeric silse-squioxane（POSS） PVK-POSS were prepared by free radical polymerization. POSS monomers reacted with vinylcarbazole and were completely dispersed at molecular level in PVK matrix and PVK-POSS nanocomposites display higher glass transition temperature（Tg） in comparison with neat PVK. Optical properties of PVK/POSS nanocomposites were investigated by UV-spectrum and PL-spectrum and the results show that the PVK-POSS nanoparticles have a good interface effect and improve color purity effectively. The maximum absorption wavelength bathochromically shifts gradually with the increasing of the content of POSS. The luminescent intensity becomes higher and higher with the increase of POSS content, and reaches its maximum luminescent intensity when the POSS content is 3% （mass fraction）, while some POSS-rich nanoparticles are present in matrix when contents of POSS are beyond 5%.     

Synthesis and properties of the chain-like polymeric copper (II) complexes bridged by bis(diphenylphosphino oxide)ethane

At room temperature, the chain-like polymeric copper (II) complexes bridged by bis (diphenylphosphino oxide) ethane (dppeO2), [Cu(dppeO2)X2]n[X=Cl(1), Br(2)] have been prepared and characterized by elemental analysis, 31P NMR, TG-DTA and X-ray analysis for [ CuBr2 (dppeO2) ] n The chain is composed of subunits containing tetrahedron coordinated copper (II) atoms. The four-coordinated copper (II) atom is ligated to another four-coordinated copper (II) atom through dppeO2. The coordination sphere of copper(II) atom is completed by two monodentate bromide and two oxygen atoms from bridging dppeO2. Crystal data are as follows: C26-H24CuP2BnO2, 0.50 mm× 0.40 mm×0.40 mm, monoclin-ic, space group: C2/c, λ= 0.07107 nm(Mo Ka), a = 1.2286(2) nm, b=2.0555(8) nm, c = 1.0652(2) nm, β = 97.366(9)°, V = 2.668nm3, Z = 4, Dcalc = 1.628 g·cm-3, R = 0.066; Rw = 0.091.     

A simple method for determining water content in organic solvents based on cobalt(Ⅱ)complexes

A method to determine water content in organic solvents was developed based on the color change of cobalt(Ⅱ) nitrate in different solvents.The color-change mechanism and optimal conditions for determining the water content were investigated.The results showed that there was a good linear relationships between the absorbance of cobalt(Ⅱ) complexes in organic solvents and water contents withγin 0.9989～0.9994.This method has the advantages of low cost,good reproducibility,good sensitivity,simple in operation,fast in detection,friendly to the environment and no limitation on linear range for determining water content.It was used to determine water in samples with a satisfactory recovery in 97.81%～101.24%.     

火焰发射法测定冶炼废渣中的铟

采用火焰原子发射光谱法对含铟冶炼废渣中的铟含量进行了测定，对测定条件，干扰因素进行了研究，并与火焰原子吸收法的结果进行了对比。     

ANALYSIS ON BUCKLING AND POSTBUCKLING OF DELAMINATION IN 3D COMPOSITES

In this paper, the problem of axisymmetric buckling and postbuckling of a circular thin-film delamination bridged by through-thickness fiber tows in 3D composites is presented. An iterativeprocedure based on Taylor's series expansion is used to generate a family of nondimensionalized post-buckling solutions of the above problem by yon Karman's nonlinear plate theory. Attention is fo-cused, herein, on the effects of the bridge force of through-thickness fibers on the buckling and post-buckling behavior of the delamination. It is found that fiber bridge not only increases the ability of re-sisting delamination buckling and postbuckling, but also brings on the jump of the delamination deflec-tion mode during the postbuckling phase. Consequently the behavior of the composite structure with de-lamination is greatly improved, such as increasing the residual strength and prolonging the service life.     

有缝拱坝的试验研究与分析

本文用试验方法研究了周边缝拱坝的应力分布规律和失稳机理,将试验结果与计算结果进行了比较,一致性较好.最后,对不同周边缝拱坝的应力状态和安全性提出了一些看法.     

Synthesis, structure and characterization of binuclear copper(Ⅱ) complexes

At room temperature, dibenzoyl peroxide undergoes oxidative addition reaction with metallic copper powder and pyridine N-oxide (triphenylphosphine oxide or 2,9-dimethyl-4,7-diphenyl-1,10-phenanthrolin) which affords the last products as binuclear copper(II) complexes, [Cu(C5H5NO)-(C6H5COO)2]2(1), [Cu(OPPh3)(C6H5COO)2]2(2) and [Cu(C6H5COO)(C26H2oN2)](3, C26H2oN2 is 2,9-dimethyl-4,7-diphenyl-1,10-phenanthrolin). The structure of the complexes were characterized by elemental analyses, IR spectra, TG-DTA and magnetic property. Crystals(1) are triclinic, space group P1,a=0.92617(36),b=1.06973(17), c=1.08813(29) nm, a=59.60(2)°, β=74.83(3)°,γ=72.80(2)°, V=0.880 nm3, Dc=1.520 g/cm3, Z=1, R=0.044, Rw=0.048, Mr=805.78, 3477 reflections with I > 3σ(I). Each copper(Ⅱ) ion is coordinated by two bridging bidentate benzoate ligands and one pyridine N-oxide or triphenylphosphine oxide to form dimeric binuclear molecules. The structure of the compound(1) shows a clear centre of symmetry.     

From Multicomponent precursor to nanoparticle nanoribbons of ZnO

A simple mild solution method is developed to synthesize a novel nanoribbon multicomponent precursor. A new 1-D nanostructure, porous structured nanoribbons which are self-assembled by textured ZnO nanoparticles, was found upon removal of ligand molecules from the ribbonlike precursor. The structure combines 1-dimensional geometry with nanoparticle morphology and displays porous structure because there are gaps/pores between the particles. The orientation textured structure of the ZnO nanoparticles can be formed by controlling the annealing time. The ZnO nanoparticle nanoribbons exhibit a long geometrical shape, uniformity, a high aspect ratio, and different optical activities with different nanostuctures. These findings demonstrate a convenient, simple technique for production of the novel one-dimensional semiconductor nanostructure suitable for subsequent processing into nanostructures, materials, and devices.     

分光光度法直接测定天然水中微量钼

本文研究了罗丹明B与硫氰酸钼形成红色络合物的问题,提出了分光光度法直接测定天然水中微量钼的新方法,方法灵敏(_600~ε=1.88×10~5)干扰少,相对标准偏差小于7%。检出限为2ppb。