Advanced Materials Research Vols. 1073-1076

Abstract: The Cu₂O/TiO₂ heterostructure nanocomposites photocatalysts with different molar ratios of Cu²⁺/Ti⁴⁺ were successfully synthesized by a simple hydrothermal procedure. The obtained samples were characterized by XRD, SEM, UV-vis DRS in order to detect the composition, the shape and the property. The photocatalytic activity of Cu₂O/TiO₂ nanocomposites was evaluated by the degradation of methyl orange (MO) as a model compound. The experimental results showed that the prepared Cu₂O/TiO₂ nanocomposites exhibited higher photocatalytic activity for the degradation of MO than the pure Cu₂O and the commercial anatase TiO₂ under visible light irradiation.

Abstract: The performance of Pd/TiO₂/Al₂O₃ catalyst for the NO_x reduction in the CO-rich conditions of simulated post Euro-IV diesel emissions at low temperature was investigated in this paper. The addition of a small amount of H₂ resulted in a visible synergetic effect. And the total amount of mixed reductant also improved the NO_x convertion. The catalyst showed NO_x conversions exceed 40% at 100~250°C when the reductant amount is 8,000 ppm with the H₂/CO ratio of 1:3, where water vapor is absence. Even though water vapor had a negative influence, 25~33% of NO_x can be decomposed using this catalyst, which is meaningful considering that it is used in a passive system.

Abstract: A quaternary non-phosphorus compound agent was prepared from polyaspartic acid (PASP), aconitic acid-acrylic acid copolymer (AA-AA), sodium gluconate and Zn²⁺. The performances of scale inhibiting and dispersing, corrosion inhibiting and biodegradability of the agent were studied. The results showed that when the formula was 4mg/L PASP , 8mg/L AA-AA, 20mg/L sodium gluconate and 2mg/L Zn²⁺, the corrosion rate was 0.0180 mm/a and the corrosion inhibition rate could reach up to 98.01% and the total concentration was not much high. The dynamic simulation test indicated that the scale inhibition and dispersing performance of the compound agent was excellent. In the complex water system which Cl^- and SO₄^2- contents were high, the corrosion inhibition rate on carbon steel was still above 90%. The quaternary compound agent applied to high hardness and high corrosivity water quality. It was a kind of high efficient environment friendly corrosion inhibitor, which could replace the phosphorous water treatment agents on the market.

Abstract: In this work, polypropylene composites reinforced by woven hemp fiber were fabricated using compression molding. The effects of compression temperature, ranging from 160 °C to 200 oC, on the tensile properties of the resulted composites were studied. The tensile tests of neat woven hemp fiber heated under different temperatures (160-280 oC) were also performed. The scanning electron microscopy (SEM) was employed to observe the fiber surface. The results showed that the tensile properties of the reinforced composites decreased with the increase of compression temperature, but a rise up to 40.31 MPa at 190 oC occurred. The tensile properties of the woven fibers decreased as the temperature increased, even a marked reduction at 220 oC. The SEM presents the fiber surface indicating the degradation of pectin or lignin on the fiber surface.

Abstract: In this paper, additive A and additive B were added into Hitec molten salts in order to optimize the properties of the molten salt. The melting point, latent heat of phase transformation, specific heat capacity, thermal gravity, and thermal stability of the modified Hitec molten salt was characterized. The results showed that compare to Hitec molten salt the modified Hitec molten salt showed low melting point, proper latent heat of phase transformation, greater heat of fusion, wide using temperature range and other advantages. The modified molten salt had good thermal properties and thermal stability. This modified Hitec molten salt has good application prospect in the aspect of high temperature heat storage/transfer.

Abstract: The rigid nature of ramie hairiness on fabrics cause severe itching feeling, which limited the application of ramie fabrics requiring for direct contact to skin. Current modification methods for ramie fabrics are ineffective, expensive or harmful to the main body of fabric. In our research, a low temperature softening method for ramie fabrics in NaOH, urea, glycerol, and Na₂B₄O₇ treatment bath was developed and proven to be efficient in lowering the stiffness and scratchiness of ramie fabrics without significant adverse effect on the fabric strength. Since it is possible to reuse the chemical agents, this treatment was relatively cheap and environmentally friendly.

Abstract: Anabaena sp. and M. aeruginosa were used to examine the toxic mechanism of nanoZnO to them, as well as the toxicity. Typical chlorophyll fluorescence parameters, including effective quantum yield, photosynthetic efficiency and maximum electron transport rate, were measured by a pulse amplitude modulated fluorometer. Results showed that nanoZnO could inhibit Anabaena sp. and M. aeruginosa growth with the EC₅₀ (concentration for 50% of maximal effect) of 0.74±0.01 and 1.68±0.01 mg/L respectively. The toxicity of nanoZnO to Anabaena sp. is higher than that to M. aeruginosa, which can be proved by the malondialdehyde content in Anabaena sp. and M. aeruginosa cells.

Abstract: The objective of this research is to prepare high surface area activated carbon (AC) from agricultural biomass materials–pine nut shells–by the method of carbonization and alkaline activation. Adsorption isotherms of creatinine (CR) by pine nut shell-based high surface area activated carbon (AC) from aqueous medium have been studied. The results have been found that samples have larger capacity for removing CR from solution. The adsorption capacity of CR as intensity at first 50 min. After 50 min, it’s smooth and steady. The carbons prepared with KOH could be effectively used for the removal of CR.

Abstract: The irradiation degradation of selected estrogens quinestrol (QS) , norethindrone (NET) and dienestrol (DS) were evaluated by electron beam . Processes using electron beam can efficiently degradate QS, NETand DS, usually at reaction dosage lower than 6KGy. Especially remarkable is the high degradation efficiency shown by oxygen saturation which is extremely favored by acidic environment. The order of the degradation rate: DS > NET> QS by different analysis methods such as HPLC. Among electron beam irradiation carried out, higher removal of 90% from solution was observed. In addition, the estrogenic activity of QS, NET and DS was carried out by rotifer test.

Abstract: Adsorption of Ni (II) onto modified attapulgite was investigated with respect to temperature, initial concentration and contact time. The kinetics data related to the adsorption of nickel from aqueous solutions were in good agreement with the pseudo-second order equation in ranges of initial concentration of 20-200 mg/L, and temperature of 298-328K.The thermodynamic experiment results showed that the equilibrium adsorption isotherm was closely fitted with the Langmuir model. Enthalpy change (△H0), entropy change (△S0) and Gibbs free energy change (△G0) were calculated from the temperature dependent sorption data, and the results indicated that the sorption of Ni (II) on modified attapulgite was a spontaneous process, and the sorption was endothermic.