Applied Mechanics and Materials Vols. 457-458

Abstract: Three novel B, N, S-containing tri(hydroxymethyl) propane (TMP) esters with different alkyl chains were synthesized and characterized. Thermal degradation tests were performed to analyze their thermal stability using a thermo-gravimetric analyzer. The friction-reducing performance of the synthesized compounds as additives in rapeseed oil (RO) was evaluated with a four-ball tester. The results show that the novel B, N, S-containing TMP esters have excellent thermal stability and possess good friction-reducing behavior when they are used as additives in rapeseed oil.

Abstract: The rice-straw particle /HDPE composites were made by compression molding process. Effects of the content of the rice-straw particle, the dosage of the titanate coupling agent and the time of hot-press were analyzed. Mechanical properties of the composites were tested, such as MOR, MOE by universal material testing machine. The result showed that rice-straw particle /HDPE composites have relatively good mechanical properties. The effect of the content of the rice-straw particle on the MOR and MOE of rice-straw particle /HDPE composites are very significant.The mechanical properties of the composite material improved by adding titanate coupling agent. The optimized processing conditions are that the content of the rice-straw particle is 50%,the dosage of the titanate coupling agent is 3%,the time of hot-press is 4 min.

Abstract: With the gradual increase of the global environmental awareness and environmentally friendly voice rising, the deal with the problem of plastic waste has become the focus of public opinion around the world has also become a hot topic of scientific research. This paper can be made of polystyrene as main raw material, adding starch and antibacterial agents containing silver nanoscale titanium dioxide, and by the synthesis of biodegradable packaging materials performance. The results showed that: 0.25mm sheet of polystyrene made of the thickness of the main raw material by injection molding process, and factors affecting the performance of the sheet, the better the performance of the film material process parameters. According to the definition of the GB/T1040-92 national standards of the People's Republic of China "plastic tensile properties of test methods and GB/T20197-2006 degradable plastics, classification, marking, and degradation of the performance requirements" and GB4789.3-94 "State Microbiological examination of coli form bacteria in the standard of food hygiene as determined by experimental methods for testing. The orthogonal experiment results show that the expandable polystyrene Dosage: 80%; starch dosage: 2%; toluene, acetone and put ratio: 3:2 .The mechanics of materials, degradation, and antimicrobial properties.

Abstract: The grinding kinetics are strongly affected by the grinding media size and style, in order to improve the grinding efficiency and solve the over-grinding problem of cassiterite in the process of grinding in cassiterite-polymetallic sulfide ores plant. A unique double-sphere grinding media has been designed and the grinding kinetics of this media with different diameters for grinding products of different size fractions have been investigated in this paper.

Abstract: A new purification procedure was used for the purification of multiwalled carbon nanotube (MWCNTs) based on nitric acid oxidation. Using thermogravimetric analysis (TGA), and Energy dispersive X-ray analysis (EDX) to characterize the morphologies of MWCNTs oxidized under various conditions. The TGA provided clear evidence for the presence of carboxylic groups (COOH) attached to the surface of MWCNTs resulting from the acid treatment.

Abstract: Polyethylene/montmorillonite (PE/MMT) nanocomposites were prepared by in situ polymerization. The morphology of MMT/MgCl₂/TiCl₄ catalyst and PE/MMT nanocomposites was investigated by scanning electron microscopy (SEM). It can be seen that MMT/MgCl₂/TiCl₄ catalyst remained the original MMT sheet structures and many holes were found in MMT and the morphology of PE/MMT nanocomposites is part of the sheet in the form of existence, as most of the petal structure. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were carried out to characterize all the samples. XRD results reveal that the original basal reflection peak of PEI1 and PEI2 disappears completely and that of PEI3 become very weak. MMT/MgCl₂/TiCl₄ catalyst was finely dispersed in the PE matrix. Instead of being individually dispersed, most layers were found in thin stacks comprising several swollen layers.

Abstract: Two nickel base multicomponent Ni-Cu-P, Ni-Cu-P-Ce alloy coatings were prepared using electroless plating method in low acidity condition, and examined by scanning electronic microscope, x-ray diffractometer and x-ray flourometer respectively on its morphology, component and structure characteristic. Thermodynamic stability of the two samples were also examined by thermal analysis method. Research revealed a microcrystalline characteristic with compact and tight surficial cellular structure of Ni-Cu-P-Ce coating. And addition of Cu and Ce into Ni-P alloy could enhance thermodynamic stability of the coating, and let coatings transformation temperature from amorphous state to crystalline state increase approximately to 480°C Celsius. X-ray diffraction analysis indicated the reaction products to be crystal grains of nickel atoms and intermetallic compound of Ni₃P.

Abstract: Nickel base multi-component alloy Ni-PNi-Cu-PNi-W-P and Ni-Co-P were prepared using electroless plating methodand examined by scanning electronic microscope, x-ray diffractometer and x-ray flourometer respectively on its morphology, component and structure characteristic. Thermodynamic stability of the three samples were also examined by thermal analysis method. Research revealed all three coatings possessed compact and tight surface structure with excellent thermodynamic stability. Also, it was more efficient to enhance the thermodynamic stability of the Ni-P alloy coating by adding atom Cu rather than atom Co or atom W. While Ni-W-P coating demonstrated a microcrystalline structure, both Ni-Co-P and Ni-Cu-P were amorphously structured. After thermal treatment three alloy coatings all experienced transformation from non-crystalline or microcrystalline state to a more stable crystalline state, XDR analysis indicated the reaction products were unit cells and inter metallic compounds of Ni₃P.

Abstract: A virtual material model of joint interfaces was established based on the Hertz contact theory and fractal theory, this model was improved by considering the influence of the elastic-plastic deformation of asperities and ameliorating the calculation methods of the elastic modulus. The simulation results of elastic-plastic considered and elastic-plastic unconsidered were compared, moreover, the finite element simulation results and experimental results were compared to fully explain the necessity of considering the influence of the elastic-plastic deformation and the the correctness of the method to calculate the elastic modulus. The research suggested that under a same load the elastic modulus of the model considering the influence of the elastic-plastic deformation was slightly larger than the un considering one, which means it could describe the characteristics of joint interfaces more accurately.

Abstract: Conductive PVAc/CNT/CB composite particles were prepared through emulsion polymerization. To get the good dispersity and chemical reactivity in the polymerization system, CNT was first modified with high concentrated nitric acid and sulfuric acid. And then in the polymerization process CNT and CB were evenly dispersed into the poly (vinyl acetate) matrix and a uniform and stable conductive network was obtained finally. A series of composite particle were prepared by changing the content of CNT. And the resistivity and structure of composite particles were determined by four-probe method and FTIR. Furthermore, the kinetics of emulsion polymerization was also investigated.