Enhancement of Ferroelectric Properties of Pb(Zr,Ti)O3 Films Grown by Metal-Organic Chemical Vapor Deposition on Noble-Alloy Bottom Electrodes

Pb(Zr,Ti)O₃ (PZT) films grown on Ir electrodes by a metal-organic chemical vapor deposition (MOCVD) have suffered from high leakage and rough surface. We sputtered Pt and Ir simultaneously onto Ti/SiO₂/Si substrates and formed Ir-Pt alloy bottom electrodes with various compositions. With an optimal composition of Ir and Pt, PZT films grown by MOCVD on this substrate showed smoother surface and suppressed leakage via the bottom interface. At the specific composition of Ir and Pt, two different phases seemed to be acquired. They constituted the electrodes and affected the PZT grain nucleation independently so that the grains with different origins grew and restrained the vicinal grains, and finally soothed the faceted-grain-formation. No fatigue was observed even in PZT on Ir-Pt alloy with much Pt content.     

Adaptive characterization of recrystallization kinetics in IF steel by electron backscatter diffraction

In this study, a rigorous methodology for quantifying recrystallization kinetics by electron backscatter diffraction is proposed in order to reduce errors associated with the operator's skill. An adaptive criterion to determine adjustable grain orientation spread depending on the recrystallization stage is proposed to better identify the recrystallized grains in the partially recrystallized microstructure. The proposed method was applied in characterizing the microstructure evolution during annealing of interstitial‐free steel cold rolled to low and high true strain levels of 0.7 and 1.6, respectively. The recrystallization kinetics determined by the proposed method was found to be consistent with the standard method of Vickers microhardness. The application of the proposed method to the overall recrystallization stages showed that it can be used for the rigorous characterization of progressive microstructure evolution, especially for the severely deformed material.     

Preparation and antibacterial activity of chitosan microshperes in a solid dispersing system

In this study, we investigated the interface contacting inhibition behaviors of chitosan against bacterial in the dispersing state. For that purpose, chitosan microspheres (CMs) in the dispersing state was prepared by the emulsification cross-linking method. The CMs had smooth surface and spherical shape with the diameter of about 124 ?m. They were stable after sterilization at 121°C and 150 kPa for 20 min. The CMs had similar antibacterial activity to that of chitosan in the solution form. Their antibacterial activities increased with the increase of the CM concentration, while decreased with the increase of pH of the system. It was found that the CMs with the degree of deacetylation (DD) of 63.6% exhibited the highest antibacterial activity, while the CMs with the DD of 83.7% exerted the lowest antibacterial activity among the three tested samples.     

Microstructure and creep properties of Mg-4Al-2Sn-1 （Ca,Sr） alloys

The effects of Ca and Sr addition on the microstructure and creep properties of Mg-4Al-2Sn alloys were examined.Tensile tests at 25℃ and 200℃ and creep tests at 150℃ and 200℃ were carried out to estimate the room temperature and high temperature mechanical properties of these alloys.The microstructure of the Mg-4Al-2Sn alloy showed dendriticα-Mg,Mg17Al12 and Mg2Sn phases.The latter two phases precipitated along the grain boundaries.The addition of Ca and Sr resulted in the formation of ternary CaMgSn and SrMgSn phases within the grain.The grain size was reduced slightly with the addition of Sr and Ca.The tensile strength was decreased by the addition of Ca and Sr at room temperature.However,the high temperature tensile strength was increased.The creep strength was improved by the addition of Ca and Sr.     

USING CAPACITIVE (RADIO FREQUENCY) DIELECTRIC HEATING IN FOOD PROCESSING AND PRESERVATION – A REVIEW

Capacitive (Radio Frequency) dielectric heating has great potential for achieving rapid and uniform heating patterns in foods, providing safe, high quality food products. This review describes and discusses the major technology behind capacitive (RF) dielectric heating in food processing and preservation, the current applications of the technology in the industry, the potential use of mathematical modeling for heating system design, and the major challenges facing the use of this technology in food processing. A vast amount of work is still necessary to further understand the dielectric properties of both food and packaging materials in order to refine system design and maximize performance of this technology in the field of packaged food products. Various economic studies will also play an important role in understanding the overall cost and viability of commercial application of this technology in food processing.     

Application of signal processing techniques to the detection of tip vortex cavitation noise in marine propeller

The tip vortex cavitation and its relevant noise has been the subject of extensive researches up to now. In most cases of experimental approaches, the accurate and objective decision of cavitation inception is primary, which is the main topic of this paper. Although the conventional power spectrum is normally adopted as a signal processing tool for the analysis of cavitation noise, a faithful exploration cannot be made especially for the cavitation inception. Alternatively, the periodic occurrence of bursting noise induced from tip vortex cavitation gives a diagnostic proof that the repeating frequency of the bursting contents can be exploited as an indication of the inception. This study, hence, employed the Short-Time Fourier Transform (STFT) analysis and the Detection of Envelope Modulation On Noise (DEMON) spectrum analysis, both which are appropriate for finding such a repeating frequency. Through the acoustical measurement in a water tunnel, the two signal processing techniques show a satisfactory result in detecting the inception of tip vortex cavitation.     

Process and Characteristics for a Surimi-like Material Made from Beef or Pork

Beef or pork was chopped, screened, and washed; water was removed by centrifugation to make surimi-like, water-washed beef or pork. Processing parameters were evaluated to develop the optimum processing techniques to yield the most functional material. Regardless of fat content in the starting material, water-washed beef or pork contained <1% fat. Water-washed muscle was lighter (reduced redness and yellowness) than the original starting material but had more color than fish surimi. Washed beef or pork formed gels with greater hardness than commercial fish surimi above 55°C after heating at 0.5°C/min. Salt soluble protein of water-washed beef or pork was higher than that of commercial fish surimi.