Advanced Materials Research Vols. 239-242

Abstract: In view of the importance of proper gate location and size in mould design process, with the basic analog theory for simulating the filling process of plastic melts in the cavity of injection moulds, injection moulding CAE technology was proposed for the optimum design of gate location and size. Based on Moldflow software, the analysis process of the best gate location and size was stated. The gate location and size and injection moulding technical parameters were optimized in this paper by example. The optimal rectangular gate dimension was 5mm×2.5mm, filling state was fine, filling time was reduced from 0.72s to 0.69s. It was resulted in products of high previewed quality, reduced the cost of production and enhanced the competitive power of mould enterprises.

Abstract: Molecularly imprinted polymers, based on the surface-modified silica gel, were prepared with silylanized silica gel as a carrier, acrylamide as functional monomer, ethylene dimethacrylate (EDMA) as crosslinker and Boc-L-phenylalanine as the template molecule. The results of HPLC shows that the imprinted polymers have good specific recognition of Boc-L-phenylalanine. The baseline separation of Boc-phenylalanine enantiomer was achieved in 20 min, the resolution was 1.84 and the maximum adsorption capacity was 6788 mg g^-1.

Abstract: The principle and method of analysis of the crystallographic planes standard equator plane projection are described in this article. Under different technological using similar Fe-3% Si silicon steel samples, conventional grain oriented silicon steel, 1150°C conventional hot-rolled grain oriented silicon steel and non-oriented silicon steel are obtained, respectively. Their pole figures of {200} planes for the samples are also obtained with XRD. The results state that the conventional Fe-3% Si grain oriented silicon steel has good Gauss texture, and 1150°C conventional hot-rolled grain oriented silicon steel has weak Gauss texture, meanwhile, non-oriented silicon steel has no Gauss texture, which prove the process has great the effect on the texture.

Abstract: Poly(N-isopropylacrylamide)(PNIPAM) with terminal aromatic groups were synthesized by atom transfer radical polymerization (ATRP), using N-isopropylacrylamide as monomer and phenyl 2-chloropropionate, (4’-phenyl)phenyl 2-chloropropionate and (2’,6’-diphenyl)phenyl 2-chloropropionate as initators. Then novel functional complexes of poly(N-isopropylacrylamide) and Eu(III) (PNIPAM-Eu(III)) with thermosensitive and fluorescent properties were synthesized and characterized by X-ray photoelectron spectroscopy (XPS), and fluorescence spectroscopy. Eu(III) was bonded to nitrogen and oxygen atoms in the polymer chain of PNIPAM and formed the complexes of PNIPAM-Eu(III). The lower critical solution temperatures (LCSTs) of PNIPAM-Eu(III) were slightly greater compared with that of PNIPAM. Europium(III) complexes had excellent fluorescence performance, the fluorescence spectrum present characteristic emission of Europium(III) at 613 nm.

Abstract: Waste polystyrene plastic as raw material was reacted with chlorine methyl polystyrene, then reacted again with the iminodiacetic acid, an environment-protecting amino acid type chelating resin was prepared. The structure of resin was characterized by IR and thermal analysis represents. The adsorption capacity of resin was measured by Atomic Absorption Spectrometer. The results showed that the resin could adsorpt Cr³⁺, Pb²⁺ well. The mechanism of adsorption conforms to Langmuir. Moreover, it can achieve adsorption balance within 30min, the adsorption quantity respectively reached 2.17 mmol/g and 2.11mmol/g at 318K.

Abstract: A novel copper and phosphorus codoped TiO₂ photocatalyst was synthesized by modified sol–gel method using tetrabutyl titanate, Cu(NO₃)₂ and H₃PO₄ as precursors. The samples were characterized by XRD, TEM, TGA, EDX. The TGA indicated the calcination temperature is 450°C. The XRD results showed undoped and Cu, P-codoped TiO₂ nanoparticles only include anatase phase, and the temperture of crystalline phase transform for Cu, P codeped TiO₂ had changed compared with undoped. The TEM analysis revealed the doping of Cu and P suppressed the growth of TiO₂ grains. The photocatalytic activity of samples was tested for degradation of 20 mg·L⁻¹ methyl orange (MO) solutions. The results showed photocatalytic activity of the catalysts with 0.5% Cu, 0.375% P-codoped TiO₂ was higher than pure TiO₂ under ultraviolet (UV).

Abstract: A homometallic mixed-ligand complex Pb(BTA)(phen)·H₂O was synthesized by taking hydrated N,N′-bis(1H-tetrazolyl)amine (H₂BTA·H₂O), 1,10-phenanthroline (phen) and PbCl₂ as starting materials during this work. The complex was characterized by elemental analysis, IR, UV-Vis, FS and X-ray single-crystal diffraction. The results reveal that the coordination number of the Pb ion is four and the geometry can be regarded as a square-pyramidal geometry, with two N atoms of BTA^2- and two N atoms of phen at the base. Crystal data for it, C₁₄H₁₁N₁₁OPb, monoclinic, space group C2/c, a = 9.420(2) Å, b = 22.943(6) Å, c = 15.286(4) Å, α = 90.000^°, β = 105.760(4)^°, γ = 90.000^°, V = 3179.6(14) ų, Z = 8, final R indices [I > 2σ(I)], R₁ = 0.0241, wR₂ = 0.0471. The thermal stability of the complex was investigated by thermogravimetric analysis. The TG profile indicates that Pb(BTA)(phen) is thermally stable up to the temperature of 588.9 K.

Abstract: Nitrogen-doped mesoporous carbons (NMC) were prepared through a facile procedure using surfactants (polyvinylpyrrolidone) as a nitrogen-containing carbon source. The NMC samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and nitrogen sorption at 77 K. Cyclic voltammetry and galvanostatic charge/discharge experiments were adopted to investigate their electrochemical behaviors. The NMC-5 sample contain abundant mesopores shows the large specific capacitance up to 276 F g⁻¹ at the current of density of 0.1 A g^-1. We suggest that the nitrogen-doped mesoporous carbon has potential application as electrochemical capacitor electrode materials.

Abstract: Carboxymethyl cellulose (CMC) made from bagasse pulp was treated by low-temperature plasma, then reacted grafting polymerization with acrylic acid (AA) to produce super absorbent polymer. The effects of discharge power, plasma treatment time, initiator dosage, acrylic acid dosage, vacuum degree and neutralization ratio on water absorbency and grafting reaction time of the products were studied by single factor experiments. The best process parameters: discharge power = 250 W; plasma treatment time = 90s; m _(K2S2O8) : m _(CMC) (W/W) = 7:20; m _(AA) : m _(CMC) (W/W) = (1:9) ~ (1:8); vacuum degree = 300 Pa; neutralization degree = 40%, in which the distilled water absorbency of the product reached its maximum of 509 g/g and the grafting reaction time approached its minimum of 2min. This process has the advantages of simple operation, easy control, high grafting efficiency, short production cycle, low cost and so on, which meet the industrial production requirements of super absorbent polymer.

Abstract: Close cylindroid shells are widely used in many industrial branches. Membrane theory of shells is used to take an analytical solution to investigate the internal force distributions and deformation laws of such shells. The result shows that, under the condition of two-point simple supports, among three force components(meridional force T₁, circumferential force T₂, and shear force T₁₂), T₁ is the dominant one, which is negative (compressional) in the vicinity of the neutral axis, and becomes positive (tensional) after being away from the neutral axis. The shear force T₁₂ is rather like a sine curve, which changes its sign at the neutral axis. This type of shear force distribution leads to a warp deformation within the cylinder. T₂ is always the tensional force, and when comparing to the other two components, it is too small to be dominant in shell designing. Somewhat similar to the three force components, among the three deformation components, the normal displacement w is the extreme one, and also it varies acutely. The circumferential displacement v is much less than w, which is compressive below the neutral axis, and becomes tensile above the neutral axis. In the nearby of neutral axis, v is nearly zero. Compared to w and v, the meridional displacement u is always the minimal.