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131.
Pınar Oğuzhan Yıldız 《Packaging Technology and Science》2015,28(12):987-997
In this study, the effect of essential oils (thyme and clove) and packaging treatments (vacuum and modified atmosphere) on the storage of hot smoked rainbow trout (Oncorhynchus mykiss) fillets over a period of 120 days at 4°C was investigated. Fillets were subjected to microbiological (total aerobic mesophilic bacteria, psychrotrophic bacteria, lactic acid bacteria, yeast and mould), chemical analyses (pH, thiobarbituric acid reactive substances and total volatile base nitrogen) and quality testing throughout the storage period. Difference in microbiological and chemical changes between samples was found to be significant (p < 0.05) during storage period. Sensory evaluation showed significant differences between the samples, and V2 and M2 samples were assessed as the most acceptable products by the panellists. In conclusion, essential oils treatment to hot smoking had a positive effect on shelf life of rainbow trout, especially clove oil showed more positive effect when compared with thyme oil. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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F. Cajner S. Kovačić H. Rafael A. Vugrinčić V. Šimunović B. Gržeta 《Materialwissenschaft und Werkstofftechnik》2015,46(1):69-77
Nitriding increases surface hardness and improves wear resistance of stainless steels. However, nitriding can sometimes reduce their corrosion resistance. In this paper, the influence of nitriding on the corrosion resistance of martensitic stainless steel was investigated. Plasma nitriding at 440 °C and 525 °C and salt bath nitrocarburizing were carried out on X17CrNi16‐2 stainless steel. Microhardness profiles of the obtained nitrided layers were examined. Phase composition analysis and quantitative depth profile analysis of the nitrided layers were preformed by X‐ray diffraction (XRD) and glow‐discharge optical emission spectrometry (GD‐OES), respectively. Corrosion behaviour was evaluated by immersion test in 1% HCl, salt spray test in 5% NaCl and electrochemical corrosion tests in 3.5% NaCl aqueous solution. Results show that salt bath nitrocarburizing, as well as plasma nitriding at low temperature, increased microhardness without significantly reducing corrosion resistance. Plasma nitriding at a higher temperature increased the corrosion tendency of the X17CrNi16‐2 steel. 相似文献
136.
Materials and Wireless Microfluidic Systems for Electronics Capable of Chemical Dissolution on Demand
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Chi Hwan Lee Jae‐Woong Jeong Yuhao Liu Yihui Zhang Yan Shi Seung‐Kyun Kang Jeonghyun Kim Jae Soon Kim Na Yeon Lee Bong Hoon Kim Kyung‐In Jang Lan Yin Min Ku Kim Anthony Banks Ungyu Paik Yonggang Huang John A. Rogers 《Advanced functional materials》2015,25(9):1338-1343
Electronics that are capable of destroying themselves, on demand and in a harmless way, might provide the ultimate form of data security. This paper presents materials and device architectures for triggered destruction of conventional microelectronic systems by means of microfluidic chemical etching of the constituent materials, including silicon, silicon dioxide, and metals (e.g., aluminum). Demonstrations in an array of home‐built metal‐oxide‐semiconductor field‐effect transistors that exploit ultrathin sheets of monocrystalline silicon and in radio‐frequency identification devices illustrate the utility of the approaches. 相似文献
137.
Effect of CO2 Exposure on the Chemical Stability and Mechanical Properties of BaZrO3‐Ceramics
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![点击此处可从《Journal of the American Ceramic Society》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Rokas Sažinas Carlos Bernuy‐López Mari‐Ann Einarsrud Tor Grande 《Journal of the American Ceramic Society》2016,99(11):3685-3695
The reactivity of BaZrO3 with CO2 has been addressed as one of the major challenges with BaZrO3‐based electrolytes in protonic ceramic fuel cells. Here, we present a study of the effect of CO2 exposure on BaZrO3‐materials at elevated temperatures. Dense BaZr1?xYxO3?x/2 (x = 0, 0.05, 0.1, 0.2) and BaCe0.2Zr0.7Y0.1O2.95 ceramics were prepared by sintering of powder prepared by spray pyrolysis. The Vickers indentation method was used to determine the hardness and estimate the fracture toughness of pristine materials as well as the corresponding materials exposed to CO2. Formation of BaCO3 on the surface of exposed ceramics was confirmed by X‐ray diffraction and electron microcopy. The reaction resulted in formation of Ba‐deficient perovskite at the exposed surface. The reaction with CO2 was most pronounced at 650°C compared to the other temperatures applied in the study. The reactivity was also shown to depend on the Y‐content and the grain size and was most pronounced for BaZr0.9Y0.1O2.95. The reaction with CO2 was observed to have a profound effect on the fracture toughness of the ceramics, demonstrating a depression of the mechanical stability of the materials. The results are discussed with respect to the chemical and mechanical stability of BaZrO3 materials, with particular emphasis on the composition and grain size. 相似文献
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Živec Tina Anžur Andreja Verbovšek Timotej 《Bulletin of Engineering Geology and the Environment》2019,78(3):1631-1643
Bulletin of Engineering Geology and the Environment - Terrestrial laser scanning (TLS) was performed in tectonically undisturbed flysch in the Elerji quarry (south-west Slovenia), which represents... 相似文献
140.
Andreja Žužić Filip Car Jelena Macan Vesna Tomašić Andreja Gajović 《International Journal of Applied Ceramic Technology》2022,19(5):2891-2904
Strontium-doped lanthanum manganites, La1-xSrxMnO3 (LSMO), are promising and affordable catalysts for oxidative degradation of volatile organic compounds. LSMO catalysts (x = 0, .1, .2, and .3) were prepared by the citrate-nitrate autocombustion (CNA) and coprecipitation synthesis. The phase composition was confirmed by X-ray diffraction and Rietveld refinement analysis, while the oxygen content was determined by Mohr's salt permanganate titration. Morphology and porosity of prepared catalysts was correlated to catalytic oxidation of benzene, toluene, ethylbenzene and o-xylene. It was observed that both synthesis methods yielded catalysts of similar average pore size diameter and specific surface area, but the pore size distribution differed: CNA-prepared catalysts had a multimodal pore size distribution, while the coprecipitated ones had a single maximum at 4 nm. Catalysts prepared by the CNA method have shown a higher catalytic activity in the temperature range 373–723 K, as the presence of Mn3+/Mn4+ mixed valences increased their reducibility. 相似文献