Advanced Materials Research Vol. 934

Abstract: Carbon nanotube (CNT) and activated carbon (AC)-supported Pd catalysts have been prepared by impregnation and reduction-precipitation method using chloropalladate acid as metal precursor. The catalytic performance for phenol in-situ hydrogenation was evaluated under 493 K, 3.5MPa. The results show that Pd/CNTs catalyst has higher selective for phenol in-situ hydrogenation to cyclohexanone. The catalysts have been characterised by CO-TPD and TEM. The mesoporosity structure and inner hollow cavities of Pd/CNTs catalyst are responsible for the distinguished properties.

Abstract: The main purpose of this paper is the analysis of the influence of steel fiber and hybrid fiber on the ultimate shear load and failure mode of rectangular concrete beams. The results of this experiment study indicate that fibers can enhance the ultimate shear load. Hybrid fibers can change the failure mode. The mechanical behavior of beam with hybrid fibers is better than that with mono-steel fibers.

Abstract: Ni-doped rod-like ZnO particles with doping concentration of 1 at.% were synthesized at 200°C by hydrothermal method and characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and superconducting quantum interference device (SQUID). The results show that the as-synthesized samples are pure hexagonal wurtzite structure without metallic Ni or other secondary phases and display rod-like shape with smooth surface. The magnetization measurements reveal that the Ni-doped rod-like ZnO particles show ferromagnetic behavior at room temperature. The saturation magnetization and coercive field are 0.0046 emu/g and 15 Oe, respectively.

Abstract: To develop a new drug delivery matrix with the suitable responsive interval, a well-defined triblock copolymer MPEG-b-PNIPAM-b-MPEG was synthesized by reversible addition fragmentation chain transfer (RAFT) polymerization. Then, the supramolecular hydrogels were fabricated via inclusion complexation with α-cyclodextrin (α-CD) and the triblock copolymers in aqueous solutions. The triblock copolymers were characterized by ¹H NMR and gel permeation chromatography (GPC), and the supramolecular structures of hydrogels was confirmed by DSC. The resultant hydrogels was found to be thermo-sensitive, and the response interval could be modulated by controlling the content of PNIPAM.

Abstract: Polycrystalline samples of Sr₃YCo_4-xCu_xO_10.5+δ (x=0, 0.2, 0.4, 0.6) have been prepared by solid state reaction method. Crystal structure has been checked by X-ray diffraction (XRD) and the results indicate that Sr₃YCo_4-xCu_xO_10.5+δ (x=0, 0.2, 0.4) with single phase have been synthesized in air, and the lattice parameters of Sr₃YCo_4-xCu_xO_10.5+δ (x=0, 0.2, 0.4) increase with increasing Cu content. Microstructure analysis demonstrates that the grain sizes enlarge and the number of pores decreases with increasing Cu content. The change of porous structure with different Cu contents is discussed by the liquid sintering theory. The temperature dependence of resistivity (ρ-T) curves of Sr₃YCo_4-xCu_xO_10.5+δ show nonmetallic behavior. And the electrical resistivity decreases successively with increasing Cu content, which is caused by the porous structure scattering the carriers as well as the increase of hole carriers.

Abstract: A novel complex of [Ag (bib)(3-pySO₃)] n (3-pySO₃:3-pyridinesulfonate; bib 1, 4-bis (2-methyl-imidazol-1-yl) butane) was synthesized and characterized by elemental analysis, IR, X-ray single crystal diffraction. The title complex belongs to triclinic system with space group P-1, a=7.8030(16)Å, b=8.0070(16)Å, c=10.742(2)Å,α=84.64(3)°,β=82.33(3)°,γ=82.76(3)°, V=657.8(2)ų, Z=2, Dc=1.894g/cm3, μ= 1.697mm^-1, F(000)= 374. Final indices is R =0.0480, wR =0.1169. Thermal stability and luminescent property of compound have also been investigated.

Abstract: A novel complex of [Ag (poa)(bpp)] n (poa:2,4-Dichlorophenoxyacetic acid;bpp: 1,3-Bis (4-pyridyl) propane) was synthesized and characterized by elemental analysis, IR, X-ray single crystal diffraction. The title complex belongs to Monoclinic system with space group P21/c, a=8.849(4)Å, b=26.654(13)Å, c=9.821(5)Å,α=90°,β=111.257(8)°,γ=90°,V=2158.7(17)ų, Z=4,D_c=1.619 g/cm³, μ=1.206 mm^-1, F(000)=1056. Final indices is R=0.0331, wR=0.0851. Therm al stability and luminescent property of compound have also been nvestigated.

Abstract: Streptomyces albus Y07, a strain which could produce ε-Poly-L-lysine (ε-PL) had been screened in our previous study. The fermentation conditions for ε-Poly-L-lysine production were further optimized through response surface method in this work. A central composite design was adopted to study the effect of culture volume, shaking speed, initial culture pH, as well as inoculation amount on ε-PL production. A quadratic polynomial equation for ε-Poly-L-lysine production was obtained by multiple regression analysis. The equation was as follow: The accuracy and general availability of the polynomial model were proved to be adequate with R² Pre = 0.8373. The optimized conditions were as follows: culture volumn: 50/500ml, culture pH = 7, inoculation amount: 10% of the total culture volume, shaking speed: 180rpm. Under the optimized conditions, the ε-PL production reached 1.085g / L. And the validity of the predicited model was further confirmed through verification experiments..

Abstract: A series of poly (butylenes succinate) with low Glycerol (GL) fraction ranging from 0 to 6‰ were synthesized by two step melting condensation. By this method, some three-dimentional branch or crosslink structure was introduced to the linear aliphatic chain of PBS. The sequence distribution, GL fraction, crystal structure and degradability were investigated. The degrability of PBS enhanced when GL was led into polymer chain as the crystalline (χ_c) decreased with GL increasing. And the degradation first happened in amorphous region and then crystal region.

Abstract: In this study, poly (butylene succinate) (PBS)/nature rubber (NR) composites were prepared, and the effects of NR content on the biodegradability were evaluated by vermiculite-degradation test. X-ray Diffraction, differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) were used to characterize the degraded blends. The weight losses of PBS/NR composites are higher than that of pure PBS, and increased with adding NR content. The weight loss of 30% NR content composite after 120 days is 16.84%. The XRD and DSC results show that the crystallinity of PBS/NR composites increase after buried in vermiculite. These results were confirmed using SEM observations by the presence of many large holes and more cracks in the degradation surface morphology of the increasing content of NR. It was observed that PBS/NR composites are green-composites or eco-materials.