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本文通过BiFeO3/La2/3Sr1/3MnO3(BFO /LSMO),研究了多铁/顺磁复合结构的界面输运以及磁电耦合机制。利用激光分子束外延技术制备了单相、质量良好的薄膜结构,采用电学、磁学、光学等多种测试手段对其输运特性、铁磁性、磁介电特性等进行了测试与表征.结果表明界面的漏电导机制是空间电荷限制电流机制;复合薄膜在室温下表现出的铁磁性主要来源于BFO层,界面处诱导出的网状磁矩会使样品产生比较明显的磁电耦合.在零场冷却(ZFC)和场冷却(FC)下,样品的磁介电系数分别在160K和170K达到极大值,介电损耗-温度曲线在150-170附近产生分裂,该温度区间与BFO层的相变相关. 相似文献
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Can Shi Ruijie Liu Ming Chang Qingzhe Jin Xingguo Wang 《Journal of the American Oil Chemists' Society》2016,93(6):869-877
In this study, we evaluated the composition of rice bran stearin (RBS) from various refineries across China. Here, we report the physicochemical parameters of RBS. The slip melting point ranged from 20.8 to 35.3 °C. The free fatty acid content (0.05–0.27 %) and peroxide value (0.34–3.70 mequiv oxygen/kg) was quite low, indicating that the RBS was of good quality. The iodine value ranged from 85.8–102.9 g/100 g, indicating a high unsaturated bond content. There was a significant difference in the unsaponifiable matter content (1.20–3.87 %) among RBS samples. The oxidative stability index (OSI) ranged from 0.56 to 5.85 h. The palmitic acid content in RBS refined by molecular distillation was significantly higher than the RBS that was refined physically and chemically. The major triacylglycerol was LLO/OLL, PLL/LPL, OLO, PLP, OOO and POO (L, linoleic acid; O, oleic acid; P, palmitic acid). RBS contained high levels of micronutrients, including total tocopherols (23.3–117.9 mg/100 g), oryzanol (0.1–2.1 %), and total sterols (682.9–1787.3 mg/100 g). Moreover, three different kinds of solid fat curves were distinguished. The results presented here are probably the first report regarding RBS on an industrial scale, meanwhile the potential utilization of RBS is discussed. 相似文献
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Hans L. Bodlaender Rodney G. Downey Michael R. Fellows Danny Hermelin 《Journal of Computer and System Sciences》2009,75(8):423-434
Kernelization is a strong and widely-applied technique in parameterized complexity. A kernelization algorithm, or simply a kernel, is a polynomial-time transformation that transforms any given parameterized instance to an equivalent instance of the same problem, with size and parameter bounded by a function of the parameter in the input. A kernel is polynomial if the size and parameter of the output are polynomially-bounded by the parameter of the input.In this paper we develop a framework which allows showing that a wide range of FPT problems do not have polynomial kernels. Our evidence relies on hypothesis made in the classical world (i.e. non-parametric complexity), and revolves around a new type of algorithm for classical decision problems, called a distillation algorithm, which is of independent interest. Using the notion of distillation algorithms, we develop a generic lower-bound engine that allows us to show that a variety of FPT problems, fulfilling certain criteria, cannot have polynomial kernels unless the polynomial hierarchy collapses. These problems include k-Path, k-Cycle, k-Exact Cycle, k-Short Cheap Tour, k-Graph Minor Order Test, k-Cutwidth, k-Search Number, k-Pathwidth, k-Treewidth, k-Branchwidth, and several optimization problems parameterized by treewidth and other structural parameters. 相似文献
77.
A multiset is a collection of objects in which repetition of elements is significant. In this paper an attempt is made to generalize the concepts of relation, function, composition and equivalence in the multiset context. As a pre-requisite a brief survey of the axiomatic approach to the multiset theory is also presented. 相似文献
78.
《Food Reviews International》2013,29(1):22-35
Emu (Dromaius novaehollandiae) is the second largest avian species in the world and is native to Australia. Emus are classified as ratites along with South African ostriches and South American rheas and are becoming popular as a source of low-fat, low-cholesterol, iron-rich red meat alternative. Emu meat has also been touted as a good source of protein, B vitamins, and creatine. In addition to its meat, emu oil has received attention for its possible therapeutic use, notably anti-inflamatory, and cosmetic benefits. However, the emu industry is very young, with already standardized hatching, feeding, rearing, and other management practices leading to the availability of a large number of grown-up birds. Hence, the emu industry is looking for science-based information in order to successfully produce and market emu meat, fat, skin, and feathers. The present review was prepared to provide information regarding emu slaughter, meat quality, composition, nutritional benefits, sensory attributes, comparison of emu meat over existing traditional meats, and emu fat and its potential therapeutic applications. 相似文献
79.
Mohamed H. Abd El‐Salam Arnold R. Hippen Kawther El‐Shafie Faiza M. Assem Hyam Abbas Mahmoud Abd El‐Aziz Osama Sharaf Mostafa El‐Aassar 《International Journal of Food Science & Technology》2011,46(10):2103-2110
Milk of high conjugated linoleic acid (CLA) level (1.25 g per 100 g milk fat) was produced by inclusion of fish oil and rousted soy bean in the ration of Holstein cows as compared to 0.55 g per 100 g milk fat in the milk of animals receiving control diet. Milk of normal (control) and high CLA content (treatment) was spray‐dried. Labneh was made from 20 g L?1 reconstituted milk using 3 mL per 100 mL yoghurt starter and 2 mL per 100 mL of probiotic cultures of Lactobacillus casei or Lactobacillus acidophilus. The control (C) and high CLA (T) labneh were analysed chemically and microbiologically, and their viscosities were determined during cold storage for 15 days. The fat content of labneh of high CLA was less than that of the control, but the total solids (TS) were unaffected by the CLA level. Labneh made with Lb. acidophilus had lower TS and higher acidity, exopolysaccharides and acetaldehyde contents and viscosity than that made with the use of Lb. casei. Labneh from the different treatments retained high counts of the added probiotic (>108 cfu g?1) throughout the storage period. The storage period had significant effects on all parameters determined. 相似文献
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