Applied Mechanics and Materials Vols. 799-800

Abstract: Prussian blue analogue nickel ferrocyanide (NiPB) decorated carbon nanotube sponge (CNT sponge) was prepared as a newly designed spongiform adsorbent. This composite material was characterized by scanning electron microscopy (SEM), inductively coupled plasma (ICP) and tested in adsorption experiments. Results show that the CNT-NiPB sponge was equipped with large holes and porous structure, a large number of MWNTs and NiPB particles uniformly deposited on the surface and internal cavities. This adsorbent CNT-NiPB sponge showed a good adsorption selectivity of cesium and strontium in mixed aqueous solution, which is mainly induced by the ion exchange reaction of NiPB and metal ions. The novel spongiform adsorbent might have a promise prospect in radioactive wastewater treatment applications.

Abstract: Four factors with three level Box-Behnken response surface design was employed to investigate the influence of whey protein isolate, sodium caseinate, glycerol and potassium sorbate concentrations in antibacterial films on mechanical properties, optical properties and water solubility. Analysis of variance and regression coefficients of models for responses showed that quadratic models were significant to predict tensile strength, light transmittance, haze and water solubility of the films, whereas elongation at break could be fitted by linear models. Among all the film-forming components, glycerol and sodium caseinate were important factors to affect these packaging properties. Sodium caseinate and glycerol contributed to increasing the elongation at break and light transmittance. With the addition of glycerol, tensile strength decreased, while sodium caseinate increased tensile strength and water solubility of films and decreased haze. Whey protein isolate=6.84g, sodium caseinate=5.11g, glycerol=35.00% and potassium sorbate=1.50g in 200ml film-forming solution would yield the film with tensile strength=9.45MPa, elongation at break=49.44%, light transmittance=65.61%, haze=15.13% and water solubility =56.02% through the optimization study.

Abstract: The hydrophilic modification of poly (vinylidene fluoride) (PVDF) membrane is achieved by using amphiphilic copolymer poly (2-hydroxyethyl methacrylate)-b-polydimethylsiloxane-b-poly (2-hydroxyethyl methacrylate) (PHEMA-b-PDMS-b-PHEMA) as addictive. The copolymer is synthesized via atom transfer radical polymerization (ATRP) and the membranes are prepared by non-solvent induced phase separation. The addition of amphiphlic copolymer has significant influence on membrane hydrophilicity and anti-fouling property. As the addictive content increasing, the water contact angle is decreased from 92° to 65°, water flux and pure water recovery rate are increased from 52.9L/m2h to 263.3 L/m2h and 71 to 95%, respectively.

Abstract: This research studied the finishing process of nano TiO₂ on PET fabric by thermal treatment. The effect of different curing temperatures of nano TiO₂ treatment on yellowness, hydrophilicity, self-cleaning of red wine stains and disperse dyeing properties of PET fabric was investigated. The results show that curing of nano TiO₂ on the PET fabric should be done at the temperature not less than 180°C. With nano TiO₂ treatment, the hydrophilicity and self-cleaning properties of PET fabric were increased. The effect of nano TiO₂ treatment on the dyeing properties of three disperse dyes, viz. C.I. Disperse Red 60, C.I. Disperse Violet 33 and C.I. Disperse Red 167, was examined. Nano TiO₂ treatment influenced on the color strength of each dyes in a different way.

Abstract: Photodegradation of phenol in aqueous solution was carried out using TiO₂ nanotubular thin film. The TiO₂ nanotubular thin film has been fabricated by sonoelectrochemical anodization process using a mixture of ethylene glycol and ammonium fluoride as electrolyte. The process was carried out at constant applied potential (20 V) for 90 minutes. After anodization the TiO₂ nanotubular film was annealed at 500 °C for 2 hours and characterized using SEM and EDX to study morphology and chemical element compositions. SEM analyses revealed that the fabricated thin film had tubular structure with the diameter between 45 – 64 nm and 6.8 um in length composed of titanium and oxygen elements were determined by EDX. The fabricated TiO₂ nanotubular thin film showed high photocatalytic activity with 80.70 % phenol degradation after 5 hours irradiation with UV light.

Abstract: Monometallic Ce, Cu and bimetallic Ce-Cu was successfully synthesized at room temperature using silica rice husk (RH) via sol-gel route and were characterized through several physicochemical techniques such as N₂ adsorption-desorption, XRD and DR/UV-Vis analyses. The prepared materials were designated as RH-10Cu, RH-20Ce and RH-10Cu20Ce. High mesoporosity with Type IV characteristics were evidenced for all the materials. The BET surface area registered for RH-10Cu, RH-20Ce and RH-10Cu20Ce were 396.02, 245.54 and 194.87 m²g^-1 respectively. Well-dispersion of metal species was clearly evidenced from XRD analysis. The strong interaction between ceria and copper was observed over RH-10Cu20Ce through DR/UV-Vis analysis.

Abstract: The ability of Citrus maxima or pomelo fruit peels for the removal of lead (II) ions in water was investigated. The influence of the different parameters such as pH, adsorption time, initial adsorbate concentration and adsorbent dosage in the adsorption characteristics was evaluated following the factorial design of experiment. Infrared spectral analyses of the adsorbent revealed the presence of hydroxyl and carboxyl bands in the structural backbone. Presence of plate-like and non-uniformity surface morphology can also be observed. Lead favors neutral to weakly basic conditions to achieve high percent removal. Lead adsorption studies in Citrus maxima followed the Temkin isotherm.

Abstract: Freshwater macroalgae, Spirogyra spp., were extracted with ethanol and analyzed the antioxidant activity. The total phenolic contents (TPCs) of Spirogyra spp. ethanolic extract (SE) were 611.38±1.51 mg gallic acid equivalents/g extract and radical DPPH scavenging activity of ethanolic extract was 5248.15±0.20 mM Trolox equivalents/g of dry weight. The Nanostructured Lipid Carriers loaded with ethanolic extract of algae called E-NLCs were prepared by the high shear homogenization method using Compritol 888 ATO, Miglyol oil, Poloxamer 188, extract and Tween 80, respectively. The Particle size (PS), Polydispersity Index (PI), Zeta Potential (ZP) and Entrapment Efficiency (EE) were determined as 110.2 nm ± 5.1, 0.22 ± 0.01 and-14.1 mV ± 1.1, respectively. The appearance of the prepared E-NLCs was spherical morphology. The EE of extract was 66.3±2.25% in NLCs system. Antioxidant potential for stabilization of fish oil was evaluated by the estimation of peroxide values (PV) of fish oil from the catfish, fish oil treated directly with natural antioxidant (SE) and in form of E-NLCs using the butylated hydroxy toluene (BHT) as standard and then incubated at 60 °C for a period of eight days. The results demonstrated that BHT have higher antioxidant potential for fish oil than SE and E-NLCs. Treatment containing E-NLCs and BHT in fish oil showed similar PV after the third day. However, the antioxidant activity of E-NLCs in stabilization of fish oil is higher than that of SE.

Abstract: In this study, highly porous activated carbon was prepared from Cyrtosperma chamissonis petioles via single step H₃PO₄ activation. The effect of impregnation temperature (RT – 90 °C) on the yield, porosity and surface area was investigated. The synthesized activated carbons were characterized by Na₂S₂O₃ volumetric method, SEM/EDX and N₂ adsorption-desorption analyses. The optimization investigation clearly showed that the impregnation temperature affected on the yield and the specific surface area of the materials. Under the optimum impregnation temperature of 75 °C, the registered iodine number and BET surface area were 1129.23 mgg^-1 and 1390.41 m²g^-1 respectively with yield percentage of 35.82. This preliminary study proves the successful conversion of plant waste into value added porous materials.