Advanced Materials Research Vols. 217-218

Abstract: Untreated and treated with alkali (NaOH), acrylic acid (AA), diammonium phosphate (DAP), and maleic anhydride (MA) of coconut filter (CF) fibers were characterized using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), and single fiber test. The composites were fabricated from CF and film resins (Polylactic-acid (PLA) and Polypropylene (PP)) using a hot press machine. Generally, our results indicated that chemical treatments improved the mechanical properties of CF fiber composites, except for the DAP-treated fiber/PP composite. The AA treatment of fiber produced the best adhesion at the fiber-matrix interface. Consequently, the tensile and flexural strengths of AA-treated fiber-reinforced polymer were the highest. CF fiber-reinforced PLA composites had better mechanical properties than CF fiber-reinforced PP composites. Our results show that CF fiber is feasible as a reinforcement for polymer composites.

Abstract: This research paper presents an experimental investigation on the compression and compressive resilience properties of warp-knitted spacer fabric composites with different resin content and different kinds of resin. By means of hand roller coating technology, four kinds of warp-knitted spacer fabric composites were made. The experiments were tested according to GB/T1453-2005 and ISO3386/2:1984. It is shown that the resin content and resin type seriously affect the compression and compressive resilience properties of warp-knitted spacer fabric composite. The data indicated that when the warp-knitted spacer fabric composite coated with the same kind of resin, with increasing resin content the elastic modulus added and the compressive resilience decreased. Having the same resin content, the compression properties of pacer fabric composite increase with the increase of flexural strength of resin; while the compressive resilience decrease.

Abstract: Various ZnO nano and microstructures, such as nanorods, microflowers composed of nanorods, and microrods were hydrothermally self-assembled. The morphology of the formed ZnO nano and microstructures could be easily tuned by varying the experimental parameters of the NaOH concentration. The crystal structure of samples was investigated by XRD, and the diffraction peaks were indexed to hexagonal wurtzite structure. A possible growth mechanism was proposed on the basis of the morphology evolution of nano and microstructures observed by SEM. Furthermore, the photoluminescence and photocatalytic properties of ZnO nano and microstructures were investigated. The results show that the ZnO microrods and microflowers exhibited higher photodegradation efficiency than that of ZnO nanorods, which maybe due to the exposed polar faces of better crystalline rather than the size of ZnO.

Abstract: This paper presents a detailed formal specification of agents and their properties and abilities,based on the Web Ontology Language (OWL). It allows an agent to be specified entirely using standard mark-up languages from the Semantic Web community, namely RDF, RDF Schemaand OWL. The basic agent components are identified and their implementation using ontology development tools is described.The description improves consistency, interoperability and maintainability of agent program. Therefore,the design errors in the early development stages could be efficiently detected and avoided.

Abstract: A series of experiment based on different mixing time were carried out to investigate the effect of mixing time on slump, modified VC value and strength properties of concrete in different consistency. The flexural strength, compressive strength on the conditions of highly stiff s, stiff and plastic system was studied. The optimized mixing time was determined and its reason was analyzed. The examination result show that the highly stiff concrete have the best performance when the mixing time is at about 120s, the stiff system is at 60s, the plastic system is at 30s.

Abstract: The cChromic shaped bricks have been used as the refractory lining in alumina kiln for long time, whose service life is about 120~250 days. Besides the short working time, the environmental pollution led to by the chromic component is also serious. In this thesispaper (thesis 是硕士论文), some materials are were chosen based on the actual situation of the usage of the refractory lining in the current alumina kiln. The choosing principals are were the extensive source and the relatively low price. Finally, a new formula of the refractory castable is was acquired based on the orthogonal test and has passed the properties testing.

Abstract: The single phase of ZnTiNb2O8 ceramics was obtained at 1050 °C via traditional solid-state method. The formation of the ZnTiNb2O8 phase in the calcined powders has been investigated as a function of calcination conditions by XRD technique. Morphology and particle sizes have been determined via SEM technique. The microwave dielectric ceramics ZnTiNb2O8 which sintered at 1150°C exibit the best microwave properties: high permittivity (εr =34.2), high quality factor (Q*f = 28696 GHz), but very negative temperature coefficient of resonant frequency (τf = -75.841ppm/°C).

Abstract: Bio-degradable polyurethane foams were prepared from the liquefied wheat straw alcohol by a reaction with isocyanate in the presence of stannous octoate, triethylene diamine and silicone oil. The influences of the catalyst, water, silicone oil, isocyanate index(IN) on the performance of the properties of the foams obtained were investigated. Furthermore, the chemical structures, thermal performance and degradation performance of the products were analyzed.

Abstract: The mechanical properties of coir fiber/line low density polyethylene (LLDPE) bio-composites were studied and micrographs of fracture surface of impact specimens for the composites were analyzed by scanning electron microscope (SEM). The flexural and impact strength of the composite with a compatilizer were higher than that of the composite without a compatilizer. The results of interface morphology of the composites with a compatilizer show better interfacial adhesion than that of the composites without one by SEM. That compatibility between the fiber and LLDPE resin is improved on, which is essential reason of rigidity and toughness increase of the composites.

Abstract: By use of the mixed layerwise theories and the interpolation functions of displacements and transverse stress, the dynamics equations of viscoelastic stiffened laminated cylindrical shells with an unconstrained fiber-reinforced layer were derived. The predicted vibration frequency and loss factor show the good agreement with the A.Okazaki’ experimental results for the two-layer cylindrical shells. The non-dimensional frequencies and loss factors were computed for different Young’s modulus and thickness of viscoelastic layer. The results show that using a higher module and thickness viscoelastic layer can effectively increase the loss factors; moreover, using a circular-reinforced viscoelastic layer has little effect on the non-dimensional frequencies, but can effectively increase the model loss factors.