On-board handling and freezing of the sea scallop, Placopecten magellanicus

The effects of on-board handling and freezing on the quality of meats from the sea scallop, Placopecten magellanicus , in the Atlantic Canadian fishery were investigated. The results show that meats frozen within 6 h of catching, pre-rigor, were markedly superior to meats frozen after storage in ice for up to 10 days, with lower drip loss, more tender texture, less flavour loss and higher overall acceptability.
Inferior results were obtained without pre-chilling of the meats before storage in cotton bags in melting ice and with live holding for 3 days followed by freezing and storage at minus 30°C for up to 6 months. Days in ice before freezing, however, exerted by far the greatest influence on quality.
According to these results, freezing on board warrants consideration on grounds of superior quality including increased yield of cooked product.     

CHANGES IN PARTITION COEFFICIENTS of ALCOHOLS AS AFFECTED BY the PRESENCE of VARIOUS FOOD SOLIDS

Using homologous series of alcohols and varing temperatures, it has been demonstrated in this study that volatility of alcohols increases upon changes in the system which decrease their solubility in the liquid. Addition of solutes has various effects on volatility, depending upon their ability to interact with water and volatiles. Surface characteristics, including the number of binding sites and surface area, significantly affect interaction. When more than one type of solids is present, alcohols preferentially adsorb to the solid with higher affinity for alcohols, until all binding sites on the solid are occupied. Silica and soy protein increase solubility of alcohols in water by adsorbing them through hydrophobic association and/or hydrogen bonds. Sodium silicoaluminate, xanthan gum and, to some extent, maltodextrin show less interaction with alcohols than with water.     

Effect of pre-existing oxide film on the electrochemical fabrication of nanoporous alumina film

Different thickness of barrier-type oxide film was intentionally grown on the Al metal surface and the effect of barrier film on the formation of nanoporous aluminum oxide film during anodization was investigated to control the nanopore structure. Analysis of potential transients during anodization indicated that anodic oxide film is initially overlaid on the barrier film but the anodic film is more facile to dissolve than barrier film. As the thickness of barrier film increases, both nanopore diameter and density decrease but the pore length is irrespective of barrier-film thickness.     

Electrochemical fabrication of SrTiO3 nanowires with nanoporous alumina template

Strontium titanate nanowires were electrochemically synthesized with nanoporous alumina template. Both chemical and electrical variables such as electrolyte pH, temperature, and current waveform were modulated to investigate the synthesis process of SrTiO3 nanowires. Superimposed cathodic pulse and diffusion time accelerated the growth of SrTiO3 nanowires, which suggested that the concentration of H+ and Sr2+ ion inside alumina template had a strong influence on the formation of SrTiO3 nanowires. Morphology and crystallinity of SrTiO3 nanowires were investigated with scanning electron microscope, X-ray diffractometer and energy dispersive X-ray spectroscopy.     

Implementation of discrete wavelet transform-based discrimination and state-of-health diagnosis for a polymer electrolyte membrane fuel cell

This research investigates a new approach based on the discrete wavelet transform (DWT) that suitable for analyzing and evaluating output terminal voltage signal (OTVS) for discrimination analysis of a polymer electrolyte membrane fuel cell (PEMFC). Due to its ability for extracting information from the non-stationary and transient phenomena simultaneously in both time and frequency domain, the OTVS can be applied as source data in the DWT-based approach. By using the wavelet decomposition including the multi-resolution analysis (MRA) using the Daubechies wavelet (dB) as mother wavelet, the information on the electrochemical characteristics of a PEMFC can be extracted from the OTVS over a wide frequency range. Thus, the cells that have similar electrochemical characteristics can be eventually discriminated. In particular, this present research develops these investigations one step further by showing low-frequency components (approximation A_n) and high-frequency components (detail D_n) extracted from variable single cells with different electrochemical characteristics. Experimental results show that DWT-based approach is clearly appropriate for the reliable SOH diagnosis for a PEMFC.     

EXPERIMENTAL DETERMINATION AND PREDICTIONS OF BREAKTHROUGH CURVES IN A FIXED BED OF SILICA GEL USING THE TRANSFER UNIT APPROACH

A semi-empirical model was developed to predict the breakthrough curves of moisture adsorption on silica gel under different operating conditions. The model requires only the basic physical and transfer properties of the flowing gas stream. Experimental breakthrough curves were determined in this study for correlating some model parameters. These dynamic experiments were carried out with different values of the gas velocity, the inlet humidity, and the properties of the adsorbent. The breakthrough curves of the modified silica gel with neutron flux in a previous study were used to verify the proposed model. It is feasible to develop a single adsorption model to simulate the fixed-bed breakthrough curves for original and modified silica gels. The results show that the complex breakthrough curves can be predicted and are in very good agreement with the experimental data.     

考虑负荷和风电出力不确定性的输电系统机会约束规划

提出了一种考虑负荷和风电场输出功率不确定性、基于机会约束规划的输电系统规划方法。将Monte Carlo方法与解析的概率潮流计算方法相结合,得到含风电场电网输电线路的有功概率潮流分布。通过改进经典的输电系统规划模型,得到考虑负荷和风电场有功出力的概率分布、基于概率潮流计算的输电系统机会约束规划模型。为了有效求解该模型,设计了一种两步式遗传算法。该方法可以有效处理输电系统规划中的不确定性,并为规划人员提供比传统方法更丰富的信息。算例证明了该方法的有效性。     

Effects of pretreatment on the aluminium etch pit formation

The effect of chemical pretreatments on the electrochemical etching behavior of aluminium was investigated with the topographic studies of surface and the analysis of initial potential transients. Two-step pretreatments with H₃PO₄ and H₂SiF₆ result in a high density of pre-etch pits on aluminium surface by the incorporation of phosphate ion inside the oxide film and the removal of surface layer by aggressive fluorosilicic acid solution. It generates a high density of etch pits during electrochemical etching and results in the capacitance increase of etched Al electrode by expanding the surface area, up to 61.3 μF/cm² with the pretreatment solution of 0.5 M H₃PO₄ at 65 °C and 10 mM H₂SiF₆ at 45 °C.     

IDENTIFICATION OF HURDLES FOR IMPROVING STORAGE STABILITY OF BRAISED KIDNEY BEANS, A KOREAN SEASONED SIDE DISH

The aim of this study was to identify factors affecting the preservation of braised kidney beans, a traditional Korean side dish, to extend its shelf life. The effects of ingredient formulation, refrigerated storage and modified atmosphere packaging on storage stability and/or sensory quality were examined. Count of yeast/mold was selected as a primary quality index from the storage test at 10C. A formulation was found in cooked kidney beans, sugar, soy sauce and corn syrup to provide the retarded microbial growth and affordable sensory quality. The temperature dependence value (Q₁₀) for the shelf life of the stretch-wrapped product was 2.0 for temperatures of 5 to 20C. Modified atmosphere packaging (60% CO₂/40% N₂ or 100% CO₂) extended the shelf life at 10C by 500% (to 36 days) compared to air packaging (6 days) based on criteria of yeast/mold growth. Equations for estimating microbial spoilage and shelf life were derived as function of temperature.

PRACTICAL APPLICATIONS

Microbial growth retardation by ingredient formulation change, chilled storage and high CO₂ modified atmosphere packaging is useful to design the processing, packaging and distribution of the Korean side dish product. Quality change kinetics of yeast/mold growth established can be used for determining shelf life of the product under different storage temperature conditions. Through the scale-up procedure, the knowledge found in this study will be useful for the industrial processing and storage of the seasoned side dishes.