Advanced Materials Research Vols. 864-867

Abstract: High acrylamide content hydrogel was synthesized under mild condition through a copolymerization reaction between acrylic acid (AA) and acrylamide (AM) using N, N-methylenebis-acrylamide as crosslinker and potassium persulfate combination with sodium sulfite as initiator in aqueous solution. The factors with influence on water absorbency performance including molar ratio of AM to AA, neutralization degree, content of crosslinker and initiator were investigated. Further orthogonal experiment with four factors and three levels were employed to determine the optimized conditions, in which not only water absorbency but also gel strength was taken into account.

Abstract: ZnO nanoparticles were synthesized by using N, N-dimethylformamide as solvent and poly(styrene-b-butadiene-b-styrene) SBS-OH as stablizer at 100°C through “in situ” reaction process. The optical properties and morphologies for the synthesized ZnO nanoparticles were measured through UV-Vis, PL and TEM methods. The results show that corona-embedded ZnO nanoparticles could be obtained by SBS-OH micelles in polar solvent DMF. The obtained ZnO nanoparticles could give an apparent quantum size confinement effects and PL results show that ZnO nanoparticles could give good luminescence properties.

Abstract: In this study, waterborne UV-curable polyurethane acrylic resin was synthesized using polypropylene glycol, toluene diisocyanate, dimethylol propionic acid and hydroxyl ethyl acrylate, and modified by hyperbranched polyester acrylate. The influent factors on hydrophilic properties and UV curing speed of the resin were discussed, and the modified resin has compared with that of unmodified resin. Results showed that the overall performance and UV curing speed of the resin modified by hyperbranched polyester was greatly enhanced, the hydrophilic property of the resin was proportional to hydrophilic group content.

Abstract: A new type of phosphate compound with different chemical composition but the same framework belonging to NaZr₂(PO₄)₃(NZP) family were synthesized by chelating sol-gel route. The factor that influence on the physical phase was investigated in this paper. The physical phase and pore structure of the synthesized powder materials were characterized by X-ray diffraction (XRD) and N₂ adsorptiondesorption respectively. The results showed that the crystalline NZP family compounds CaZr₄(PO₄)₆ and KZr₂(PO₄)₃ which is occupied by Ca²⁺ and K⁺ respectively at lattice site of M_Ican be prepared by sol-gel route followed with calcinations at 700-800°C for 2h, but when the gel precursor of CaZr₄(PO₄)₆ was treated by hydrothermal crystallization at 160°C for 24h, the obtained powder was NH₄Zr₂(PO₄)₃ instead of CaZr₄(PO₄)₆.

Abstract: Molecular imprinting has been considered as one of the most useful techniques for the preparation of specific receptors. In this study, a novel molecularly imprinted material (MIP) has been developed by combining PFOS as the template with soluble polybenzimidazole which wrapped over the surface of ferroferric oxide as the carrier. Kinetics experimental showed MIP had a sorption amount of 117.6mg/g for PFOS, high than 74.6mg/g of the none-imprinted polymer adsorbents（NIP）. Additionally, in the competitive environment with other pollutants, the sorption amount of PFOS for MIP is greater than NIP, due to the electrostatic interaction in recognizing the target compound.

Abstract: The study aimed to investigate the adsorption efficiency of methyl violet (MV) dye on activated carbon (AC) derived from coffee residues. A batch adsorption study was performed to examine various contributory parameters including contact time, solution pH, adsorbent dose and initial dye concentration. The morphology of the AC was studied by means of scanning electron microscopy (SEM). The results showed that maximum adsorption of MV dye on activated carbon occurred with a contact time of 60 min, solution pH of 9.0 and adsorbent dose of 0.3 g. The equilibrium adsorption data were analysed using Freundlich and Temkin isotherms. The adsorption isotherm was found to follow the Freundlich isotherm. Adsorption behavior of MV dye follows mechanism of physical adsorption which is occurred by heterogeneous surface. The results indicate that the AC from coffee residues is a suitable adsorbent for the adsorption of dyes.

Abstract: TiO₂ nanotubes were obtained by calcining at various temperatures. The influence of calcination temperature on the degradation activity of TiO₂ nanotubes for Cr (VI) was investigated under UV light irradiation. It was found that the photocatalytic activity of TiO₂ nanotubes calcinated at 350 °C was the highest. Furthermore, the photocatalytic activity of TiO₂ nanotubes was higher than that of the P25 TiO₂ nanoparticles. Importantly, the stability of TiO₂ nanotubes for the degradation of Cr (VI) was high, and degradation efficiency can still reach 72.4% after 8 recycles. Consequently, a highly stable and active photocatalyst for degradation of Cr (VI) was achieved.

Abstract: The calcined Mg-Fe LDH adsorbent (CLDH) was fabricated by co-precipitation and calcination processes. The adsorbent was characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy. The adsorbent exhibited high adsorption capacity for the removal of acid red G (ARG) dye. The effects of the adsorbent dose, solution pH, contact time, reaction temperature and initial ARG dye concentrations upon the ARG dye adsorption were investigated in detail. The kinetic studies indicated that the adsorption process was fitted well with the pseudo-second-order kinetic model (R² > 0.99). The equilibrium data were well described by the Freundlich equation. Moreover, after three regeneration cycles, the CLDH still showed high adsorption capacity. The results showed that the CLDH is an efficient adsorbent for the removal of organic pollutants from wastewater.

Abstract: Black carbon, which is taken the sources from the products of the incomplete combustion or pyrolysis of organisms or volatile components of fossil fuels, has a large specific surface area and strong adsorption capacity for organic matters. Nowadays, black carbon has been widely used as the adsorbent or passivating agent in environmental pollution control. However, black carbon is a hydrophobic non-polar adsorbent, which results in the difficulty of dispersing in the solution without modification. Thus, in order to increase the surface oxygen-containing groups, the modification should be done before black carbon used to adsorb or inactivate heavy metal. The concepts, sources and application status of black carbon in environmental pollution control are summarized. Meanwhile, the modification methods and the application prospect of black carbon are put forward.

Abstract: Field plan has been the important work in hydraulic engineering, this paper introduces how to combine quantitative and qualitative analysis together and turn the hard quantify factors into the model Make the result of calculation is more tally with the actual and meet the needs of the reality.