Advanced Materials Research Vols. 233-235

Abstract: Thymol had been confirmed to be applied to prevent the growth of bacteria and function as an antioxidant to maintain the quality of food products. It is known that a number of components of essential oils including thymol are suitable to form inclusion complexes with β-Cyclodextrin, since they fit the hydrophobic cavity tightly. The β-cyclodextrin-thymol(β-CD-thymol) inclusion complexes were prepared by the saturated water solution method. SEM results showed that the lattice of β-CD-thymol inclusions was different from hydrogen-bond-type crystal lattice of β-CD and β-CD-water inclusions; the disappearance of high-energy water molecules in the β-CD cavity was observed from SAT data; the aromatic ring of the thymol was included in the β-CD cavity, according to the FTIR data. Besides, according to the calculation of chemical structure, molecular size of thymol was estimated. These results supported a successful formation of the inclusion and the preliminary structure of host-guest inclusions was constructed, indicating the -CH₃ is close to the β-CD narrower rim, while the -CH₂ and OH group is close to the wide one.

Abstract: Sasobit has been applied into asphalt successfully since 1997. From then on, a lot of studies emphasizes on how Sasobit can lower asphalt’s viscosity and reduce poison odor emission. However, the durability of asphalt containing Sasobit is ignored to research. This paper aimed to analyze Sasobit impact on the durability of asphalt. In this study, the Sasobit modified asphalt was blended using different Sasobit contents of 2%, 3%, 4% and 5% by weight of asphalt into the base asphalt (SBS modified asphalt). The Rolling Thin Film Oven test (RTFO) and Pressure Aging Vessel test (PAV) were conducted to simulate the mixing and construction aging and in-service aging of asphalt. The properties and micro-structure of the base asphalt and Sasobit modified asphalt in three different aging states (original state, mixing and construction aging state and in-service aging state) were tested by using the Penetration-Grade system, Performance-Grade system and fluorescence microscope. The aging indexes of the base asphalt and Sasobit modified asphalt were calculated to compare their durability. It was evident that the durability of the Sasobit modified asphalt was mostly affected by the type of base asphalt and Sasobit had a little impaction on the durability of the asphalt.

Abstract: Based on the microscope phase-field model，the evolution of atom morphology, the long range order(lro) parameter and concentration can be gotten, and atomic clustering and ordering during the precipitation process of Ni-Cr-Al alloy could be obtained. The Ni-14at.%Cr-15.5at.%Al alloy is studied and the temperature of precipitation are 973K. It was showed that the ordering of both Al and Cr atoms take place simultaneously during the precipitation process of Ni-Al-Cr alloy, Cr atoms transfer to the boundaries of L1₂ phases, the domain of rich Cr atoms are formed. At the boundaries of L1₂ phases, Cr atoms may substitute the Al sublattice, and the D0₂₂ phases are formed.

Abstract: PPC is a new biodegradable aliphatic polycarbonate with poor thermal stability and mechanical properties which is difficult to form sheets or films and so on. Through the addition of alkali lignin, thermal stability and mechanical properties of PPC was improved largely. PPC/ alkali lignin sheets could be prepared. DSC results showed that the thermal stability of PPC was improved by the introduction of alkali lignin. SEM showed good dispersion of alkali lignin particles into PPC matrix that resulted in good miscibility. Improved mechanical properties and thermal stability of PPC/ alkali lignin blends were attributed to stronger interfacial interaction of PPC and alkali lignin. These results indicate that blending PPC with alkali lignin is an efficient and convenient method to improve the properties of PPC.

Abstract: Y zeolite was synthesized form silica gel microsphere by in- situ hydrothermal method, with appropriate amount of other constituents, such as sodium silicate, water, without adding any organic additives. The as-synthesized samples were characterized using powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and N₂ sorption. The results show that the synthesized sample not only has a composite structure with zeolite Y and silica gel, but also retains the shape of silica gel microsphere. The pore distribution of the composite materials indicated that the composite material contains two types of pore that are micropores and large pores.

Abstract: The scrap iron used in micro electrolytic technology was from the waste of a fabrication plant, this behavior possessed an effect of treating wastes with processes of wastes against one another and the generated Fe²⁺ can be used in the Fenton oxidation process, Fe³⁺ generated from which can be linked up with the flocculation technology. So it was capable of cutting down the cost and improving the treatment effect using micro electrolysis coupling with Fenton oxidation-flocculation technology to treat medium pulping wastewater. pH is an important influencing factor of micro electrolysis, Fenton oxidation and flocculation, and in this study the influence of pH on micro electrolytic technology was studied firstly, the results showed that the removal efficiency of COD and chrominance reached 65% and 60%, respectively and the concentration of generated Fe²⁺ reached 157mg/L when pH was 4. Then the influence of pH on the Fenton oxidation process was studied, the results showed that without extra Fe2+, the removal efficiency of COD by Fenton process increased at fist and then decreased with the increase of pH, and the removal efficiency of COD and chrominance reached 84% and 83%, respectively, and the concentration of generated Fe³⁺ reached 217mg/L at this moment. At last the study of the influence of pH on the flocculation effect with generated Fe³⁺ and PAM was carried out, the results showed that the COD removal efficiency reached 41% and the chrominance removal efficiency reached 75%, the final chrominance was 4 and the COD concentration was 45mg/L which was lower than 60mg/L, that met with the first order of effluent standard.

Abstract: The spinel ferrite system Ni_1-xMn_xFe₂O₄ (x = 0.0, 0.25, 0.5, 0.75) nanowire arrays with an average diameter of about 80 nm, have been synthesized into nanopores of anodic aluminum oxide (AAO) template using the sol–gel technique. X-ray diffraction analysis shows the formation of single-phase nickel manganese ferrites. Scanning electron microscopy and transmission electron microscope images indicate that the nanowire arrays are composed of prolate spheroids with different crystal orientations. Magnetic measurements show that the saturation magnetization (M_s) of nickel ferrite nanowire arrays is lower than that of bulk ones. But the M_s of the samples doped with Mn are greater than that of bulk ones. We do not observe obviously easy magnetization direction of all nanowire arrays. The possible reasons that are responsible for the composition dependence of the properties are discussed.

Abstract: In order to construct the in vitro cell culture model occurring in biochemical and biophysical environment in vivo, and to establish quantitative detection and control of mechanical properties of substrate, a low modulus material polyacrylamide hydro-gel (PAHG) was synthesized and used as the substrate material for in vitro cell culture. Using a modified tensile device based on the principles of buoyancy for balance out gravity deformation and by detecting the minor deformation with the aids of computer graphic processing software, the measurement of low elastic modulus (E) of PAHG was established. By analyzing a large number of experimental data, the effect of two key factors (molar ratio of cross-linker/monomer and water content) on elastic modulus was investigated, and the influence of cross-linker/monomer (d) on saturated water content (w) was also discussed. Mathematical model for d, w and E of water saturated gel in vitro cell culture state was built up by regression analysis of experimental data. Based on the model, the d for PAHG with a given elastic modulus in water saturated state was calculated and applied to the synthesis of PAHG. The results showed that the elastic modulus of thus-obtained PAHG in water saturated state is in agreement with the given value with a relative error of 0.025-0.12, suggesting that the mathematical model is applicable for the prediction of properties of low modulus materials.

Abstract: The zirconium phosphate α-Zr(HPO₄)₂·H₂O (α-ZrP) with layered structure has been synthesized by refluxing method. Power X-ray diffraction (XRD), vibrational spectroscopy (FT-IR, FT-Raman), thermal analysis (TG-DSC), transition electron spectroscopy (TEM), scanning electron microscopy (SEM) and energy dispersive X-ray spectrometer (EDS) was respectively used for structure characterization of the compound α-ZrP. The result of intercalation reactions with tetramethylammonium bromide and cetyltrimethylammonium bromide showed interlayer distances increase of ~ 0.46 nm and ~ 1.68 nm, respectively. The BET surface area of α-ZrP is 12.29 m²·g^-1. The cyclic voltammetry behaviors of the compound on Au electrode showed a typical reversible process. Moreover, the strong fluorescent property of the α-ZrP was measured. The maximum emission peaks occurred at ca. 390 nm upon excitation at ca. 288 nm.

Abstract: Poly(ethylene terephthalate)(PET)/poly(trimethylene terephthalate)(PTT) /Montemorillonite(MMT) nanocomposites were prepared by melt blending through a co-rotating twin screw extruder. The wide angle X-ray diffraction(WAXD) patterns proved the nanocomposites formed exfoliated or intercalated structures. The rheological properties of PET/PTT/MMT were studied by RH2000 capillary rheometer. The results show that PET/PTT and PET/PTT/MMT melts are all pseudo-plastic fluids, and the addition of one to five part MMT can obviously improve the flow property of PET/PTT melt. The apparent viscosity (η_a) of the nanocomposite melts is lower than that of PET/PTT melt, and their flow behavior is better than that of PET/PTT melt, so the nanocomposites can be processed at lower temperature. The viscous flow activation energy(ΔE_η) of the nanocomposite melts is higher than that of PET/PTT melt, and it is more proper for the nanocomposite melts to improve their flow properties by increasing temperature.