Applied Mechanics and Materials Vols. 490-491

Abstract: Polystyrene (PS) nanoparticles/multi-walled carbon nanotube (MWCNT) composites were prepared by emulsion polymerization in the presence of styryl-modified MWCNTs. The Fourier transform infrared spectroscopy and scanning electron microscope confirm the effectiveness of functionalization of MWCNTs and the strong interactions between MWCNTs and PS nanoparticles. The results of transmission electron microscopes further support the covalent functionalization process.

Abstract: Based on the inorganic and organic composite pretreatment technology, a new chromium-free pretreatment solution consisting of Ce (NO₃)₃, N-β (aminoethyl)-γ-aminopropyl trimethoxysilane (KH792) and vinyltrimethoxysilane (KH171) was studied and used to treat galvanized sheet. Corrosion resistance of composite silane films on galvanized sheet surfaces was studied using CuSO₄ pitting corrosion test and neutral salt spray test. Experimental results show that the corrosion resistance of composite silane film has improved significantly, compared to single silane film. The optimal condition of chromium-free pretreatment solution is that KH792/KH171 ratio is 4/1(v/v), Ce (NO₃)₃ content is 0.05%(w/w).

Abstract: In the present work, the effect of the microstructure of AlSi6Mg2 alloy on its macro-rheological behavior of the steady AlSi6Mg2 alloy is investigated. Specifically, the effect of particle size, packing mode and degree of the agglomeration of particles are analyzed. It can be seen that the apparent viscosity decreases with increasing the particle size (d) if d is between a few μm and 200 μm, while the solid particle size does not affect viscosity except this region. This theoretical prediction is in qualitatively agreement with the experimental data. The trend of the variation of the average agglomerate size with the particle size is the same as the one of viscosity. The packing mode of solid particles in agglomerate is closely related to the solid volume fraction and the characteristics of the alloy system. Subsequently, the state of agglomeration of solid particles which determines the rheology of semisolid AlSi6Mg2 alloy, while the external flow conditions (such as shear rate) influence the viscosity by changing the state of agglomeration. Consequently, the particle size, the packing mode and the average agglomerate size have different effect on the rheological behavior of SSMS.

Abstract: It is first attempted to demonstrate the catalytic efficiency and structure-sensitivity reactions on the surface of carbon nanotube (CNT) encapsulated with metal oxide particle. The results shows that the encapsulated nanoparticle CuO activate the outer orbits of CNT, and hence the surface of CuO@CNT is chemically active for hydroxyl radical generation. The results obtained from DFT calculation and experiments verified the highly active of CuO@CNT catalysts for the generation of hydroxyl radicals, and the structure-sensitivity for the oxidation of dichlorophenol. This suggests a novel strategy to design well-defined interfaces, controlling the structure-sensitivity reaction, can hence markedly improve the performance of catalysts.

Abstract: Room-temperature SiO₂ atomic layer deposition (ALD) on soft, flexible materials of acrylic resin and polystyrene is developed using tris (dimethylamino) silane and plasma-excited water vapor. The growth rate is measured to be 0.13 nm/cycle at room temperature on the acrylic resin surface. The SiO₂ coating on the soft materials was examined by X-ray photoelectron spectroscopy and an organic solvent resistant test. This process is applicable as a surface treatment for improving chemical resistivity of the soft materials.

Abstract: The last two decades have witnessed a plethora of novel biomaterials that work significantly in the discovery of drugs and the point check of drugs, Biosensors. PLGA (Poly-(L-Lactide-co-glycolic Acid)), has already been shown to be a substrate for manufacture of substrates for OFETs, that in the future would be the forefront of electroceuticals. But, Polylactic Acid (PLA) derived and pegylated nanoparticles generated scaffolds, promote neural self-differentiation, nanowires derived from Polythiophene (PTs) can be utilised in the area of biosensors. Similarly, PT derived PEDOT:PSS(poly (3,4-ethylenedioxythiophene) poly (styrenesulfonate) polymer doped with appropriate cations is useful to manipulate directly the biological response of cells on the same grounds, organic electrochemical transistors (OECTs) based on PEDOTPSS coupled with bilayer lipid membranes (BLMs) were shown to act as ion-to-electron converters. A solid-state ion bipolar junction transistor (IBJT) has been developed to serve as a circuit element for neurotransmitter signal delivery. Consequently, the traditional drug discovery methods have far gone by. This era demands a much more modified and multiple disciplined methods for modern drug discovery. This review gives an insight and instance of this paradigm.

Abstract: The magnesium alloys with rare earth element addition are widely used as nodularizer recently. However, the low absorption rate of Mg and lots of white smog during burning become critical issue. In this paper, a new type of iron coated nodularizer is developed to solve the above problems and reduce the production cost. The microstructure and mechanical properties also investigated.

Abstract: Scratch tests on (001) face, doubler face and tripler face of KDP crystals are carried out at room temperature. It shows that the friction ceoffcients of different crystal faces are affected seriously by the crystal oritations, their variation periods of (001) face, doubler face and tripler face are 90^o, 180^o and 180^o, their attitudes of relative anisotropy are 50%, 43.8% and 43.8%, and all of them are less than 0.4. The scratch mechanism of KDP crystal consists of four types: elastic and plastic deformation, ploughing, microchip, and surface damage. Differences between elastic and plastic deformation and ploughing are not obvious due to the soft-brittle nature of KDP crystal.

Abstract: Sasobit warm mix drainage asphalt pavement has become increasingly popular due to its environmental benefits and comfortable using effect. However, test results show that its low-temperature and anti-fatigue performance have a certain degree of reduced. To improve the performance of asphalt four different doses (1%, 3%, 5% and 7%) of salt are added to the Sasobit asphalt. Laboratory tests were used to simulate short and long term aging asphalt in the process of construction and using pavement. A series of binder tests including bending beam rheometer (BBR), dynamic shear rheometer (DSR) and Brookfield viscosity tests were conducted. Results show an increase of rutting performance for warm mix binders with Sasobit while asphalt with salt has similar high temperature performance to original asphalt. Unlike Sasobit which has a decrease of cracking performance for asphalt at low-temperature, salinity can greatly improve the Low-temperature performance. And the low-temperature cracking performance and anti-fatigue performance presents a tendency of climbing up first and then declining with the increase of salinity. The figure of viscosity-temperature curve shows that the optimum of salinity is 5%.Further more, asphalt with Sasobit and salt can gain better performance and same mixing and compaction effect in lower 20°C than hot mix asphalt without it.

Abstract: Two heavy metals (nickel and cadmium ) in 15 specis of wild mushrooms were determined using flame atomic adsorption spectrometry (VARIAN, SpectrAA-220Fs). The mushrooms were collected from Miyi, China. The study explored the accumulation of heavy metals in different macrofung. It is found that the range of Nickel and Cadmium in mushrooms were 1.78-21.22 mg/kg and 0.47-21.84 mg/kg. Minimal and maximal concentrations of heavy metals were determined in Lentinus edodes and Boletus edulis for nickel, Russula alutacea and Russula delica for cadmium,respectively. The order of the levels of heavy metals in the mushrooms samples was found to be as Ni>Cd. Cadmium values in wild mushrooms collected from Miyi were generally higher than the previous studies. Nickel contents were in agreement with the literature value.