Advanced Materials Research Vol. 910

Abstract: Exposing the Early effect (or called channel-length modulation effect) at deep subnano node high-k/metal gate (HK/MG) process is still beneficial to IC designers to reduce the obsession in design. This effect contributes the operating point in circuit concern and process adjustment. For the long channel device, the intercept under various gate voltages focuses on one point consistent with conventional device. However, the divergent phenomenon was observed at the short channel tested device due to the higher strain effect, causing the non-uniform electrical field distribution in channel.

Abstract: Following the investigation of the relationship among the annealing temperatures for decoupled plasma nitridation (DPN) process to indirectly manipulate the amount of oxygen vacancy in high-k (HK) gate dielectric, the expected threshold voltage (V_t) of n-channel MOSFET (nMOSFET) device is able to be approached. The uniformity of V_t values related to the channel lengths was fine due to 10% deviation specification, but the roll-up phenomenon coming from the strain effect was observed. The lower annealing temperature shows the higher V_t value due to the higher interface state density, reflecting at the subthreshold swing (S.S.) characteristics.

Abstract: Structural relaxation through isothermal annealing below the glass transition temperature was conducted on a Zr_64.13Cu_15.75Ni_10.12Al₁₀ bulk metallic glass. Differential scanning calorimetry was used to quantify enthalpy differences between the as-cast and relaxed samples, which were then related to average free volume differences. The influence of structural relaxation on plasticity was examined. While the free volume decreasement can be clearly observed between the as-cast and relaxed samples, structural relaxation is not accompanied by severe embrittlement.

Abstract: Depending on available theory and literature about chitosan (CS), the paper studied the method of preparation of CS block in fluffy meshwork shape with fine hair shape and analysis its structure to adapt to application for drug controlled-release material. Primarily, CS was extruded to fine fair fiber by spinning after preparing CS solution. CS Block with reticulate structure design were carried out in this experiment. This research will be showed how to choose appropriate molding process, through selecting CS solution concentration and extruding spinning to prepare pure CS fluffy network with fine hair. The CS reticulate body obtained showed good degradation characteristics in simulated body fluid (SBF). The change of morphology to describe its biological characteristics is not only related to material composition but also to the structure of the fluffy network which is mainly controlled by the molding process. Also, the microstructure, morphology and crystallinity of the net CS hydrogels were characterized through Fourier transform infrared spectroscopy and scanning electron microscopy. This research should provide the theory basis and technical way to design and fabricate for CS as the carrier of the drug release.

Abstract: Deep desulfurization of a hydrotreated diesel fuel was investigated with TBHP oxidation coupled with solvent extraction intensified by ultrasound. The process parameters for the oxidation desulfurization of diesel fuel, such as the type and dosage of catalyst, co-solvent, ultrasound time, molar ratio of TBHP and sulfur were investigated. The results showed that sulfur content of the hydrotreated diesel fuel was reduced from 140 ppm to 12 ppm with using 1%wt of sodium tungstate as catalyst, 20%wt of methanol as co-solvent during the reaction, reaction temperature at 90°C, ultrasound time for 15 min and TBHP/Sulfur molar ratio of 32, and ultrasound irradiation had the obvious reinforcement in oxidative desulfurization of diesel fuel.

Abstract: In wire electro-discharge machining with an extremely high travelling speed of wire electrode (WEDM-HS), the emulsion is used as working liquid. Because there exists a functional electrolyte, the EDM spark can operate under a relatively large spark gap size condition, and this would facilitate the removal of machined debris. An investigation has been made into the machining feasibility when WEDM-HS has been employed to process Al₂O₃ particle reinforced aluminum alloy 6061 with 10-vol% Al₂O₃ (10ALO). And the material removal rate (MRR) has been examined in this study. Since there are many factors that can influence the MRR in the WEDM-HS process, in order to determine which is the most important factor and to optimize the machining parameters, the relative importance of the various machining parameters on material removal rate was established by utilizing an orthogonal experimental analysis. The results of the analysis suggest that to achieve a high MRR for particulate reinforced aluminum 6061 with 10-vol% Al₂O₃, the duty cycle is the most influential factor among current, pulse duration and duty cycle. And the impact of the different factors follows the sequence of duty cycle > current > pulse duration.

Abstract: Light is one of the most important factor in the growth of plants, with the advent and application of biological materials such as different artificial LED source, the new agricultural technology has been rapid development. In this study, first established the gray GM (1,1) prediction model of the pepper seedlings chlorophyll changes under the different light and then compared of the chlorophyll models under the different light. Last the study found that different artificial LED have the different effect and the forecasting curve and prediction model under the blue is optimal for pepper seedling by comparing the chlorophyll curves and predictive models of pepper seedlings under different light, so blue light is the most suitable for the growth of pepper seedlings. The results turned out that accuracy test of the three gray prediction models can achieve the best grade, and the three gray prediction models have the good practical value. Grey prediction theory can be better applied to the study of the plants.

Abstract: P(BA-St), a good modifier for epoxy resin, was prepared by BA and St in situ polymerization. The modified resin system was based on diglycidyl ether of bisphenol and methyl tetrahydrophthalic anhydride, tris (dimethylaminomethyl) phenol. The influence of the copolymer on mechanical properties and thermal performance of the systems was studied. When 15 wt% of the BA/St with a weight ratio composition of 7.5/7.5 was added to epoxy, high performance modified epoxy resin was obtained.

Abstract: Elastic modulus of a coating is an important property for design and use of the coating. At present, many methods have been put forward to evaluate the coating elastic modulus. However, each methods has special property, which make the elastic moduli from them are different. In the study, elastic modulus of a porous Ti coating has been evaluated by three-point bending test and indentation method. The results show that the coating elastic moduli from the two different methods agree well, which can reflect the uniformity of the pore structures of the porous coating. Meanwhile, the little deviations among the different test points of indentation method could reflect the uniformity of the coating structure partly.

Abstract: With the development of techniques, the acoustic performance of 3C electroacoustic products, such as earphone, headphone, microspeaker and etc., will be paid much attention. Ventilation material which is often used in the front and rear side of the product is also an important component to affect the acoustic performance. Depending on the diverse manufacture processes and materials, there are many kinds of ventilation materials, including paper, mesh, poron, nonwoven and etc.. This study aims to investigate acoustic characteristics of these ventilation materials, including air permeability, reflection coefficient, and acoustic impedance. The result indicates that mesh with different code number shows similar air permeability. Meanwhile, the reflection coefficients of each mesh material have no significant variation with the frequency. For the lower frequencies, the level of acoustic impedance is much related to the structure or material used. With the increment of frequency, the acoustic impedance of all the materials will converge to a certain value even for the higher density material.