乌骨鸡磷脂侧链脂肪酸的GC-MS分析

用氯仿:甲醇(2:1)超声提取乌骨鸡总磷脂,丙酮脱油精制后,经皂化、甲酯化处理,应用GC-MS联用技术对其侧链脂肪酸组成进行分析,并以面积归一法,计算各脂肪酸的相对百分含量.结果显示,乌骨鸡总磷脂中含有硬脂酸27.46%、花生四烯酸21.39%、油酸18.22%、亚油酸16.67%、棕榈酸12.13%、二十二碳六烯酸(DHA) 2.26%、二十碳三烯酸1.71%、棕榈油酸0.16%.不饱和脂肪酸和多不饱和脂肪酸的含量分别为60.41%和42.03%.乌骨鸡磷脂侧链脂肪酸中高比例的多不饱和脂肪酸和花生四烯酸含量是乌骨鸡磷脂的显著特征.     

Resonant-induced transparency and coupled modes in layered metamaterials

We present an overview of some of our work on transmission properties and mode characteristics of layered metamaterials and their potential applications. In particular, we will show how layered metamaterials exhibit unusual transmission properties and unconventional features of guided modes, such as resonance-induced transparency in multilayer structures and slope reversal of dispersion curves in coupled waveguides. PACS 78.67.-n; 73.21.Ac; 61.46.+w; 42.25.Bs; 42.82.Et     

Dynamic behavior of discrete-time multiagent systems with general communication structures

In this paper, we discuss the dynamic behavior of networks of dynamic agents with general communication topologies. We first analyze the basic case: systems with communication topologies that have spanning trees, i.e., the systems that solve consensus problems. We establish an algebraic condition to characterize each agent's contributions to the final state. And we also study the influence of time-delays on each agent's contributions. Then, we investigate the general case: systems with weakly connected topologies. By using matrix theory, we prove that the states of internal agents will converge to a convex combination of boundary agents in the absence or presence of communication time-delays, and we also show that the coefficients of the convex combination are independent of time-delays even if the delays are time-varying. These results have broad applications in other areas, e.g., study of swarm behavior, formation control of vehicles, etc.     

LIMITING BEHAVIOR OF UNIFORM RECURSIVE TREES

The authors consider the limiting behavior of various branches in a uniform recursive tree with size growing to infinity.The limiting distribution ofζ_(n,m),the number of branches with size m in a uniform recursive tree of order n,converges weakly to a Poisson distribution with parameter 1/m with convergence of all moments.The size of any large branch tends to infinity almost surely.     

选择性远程DEPT~(13)C NMR新技术用于新阔叶千里光碱氮氧化合物的结构测定和谱峰归属研究

从湖北蟹甲草根茎中分得一个新的生物碱,选择性远程DEPT~(13)C NMR新技术用于识别NMR信号归属和连接被季碳及杂原子分割的质子自旋系统,确定其结构为新阔叶千里光碱的氮氧化物,如(1)所示。     

Bioisosterism between Sulfonyl Group and Phosphoryl Group-The Synthesis of New ALS Inhibitors N-(Arylamino Hydroxyl Phosphoryl)-N'-(4,6-Dimethoxypyrimidine-2-yl)ureas

Sulfonylureaherbicidesisanewclassofherbicidesdiscoveredinthemid-l97O's',whosemodeofactionhasbeenestablishedastheinhibitionofacetolactatesynthase(ALS,alsoreferredasacetohydroxyacidsynthase)'-Muchattentionhasbeenfocussedonthiskindofcompound,sincetheyhaveunprecedenteduserates,ahighdegreeofselectivity,andexcellentenvironmentalsafety'.NumerousmodificationsofthestrUctureofthisclassofherbicideshavebeenreported'.Wehavetakenattentiontothesimi1alltybetweenthesulfonylgroup(-SO2-)andphosphoryIgroup[-P…     

单色光石英退偏器的退偏机理及性能研究

研究了单色光石英退偏器的退偏机理；定义了退偏度作为衡量退偏器性能的物理量。从实验上在４４０～９２０ｎｍ的光谱范围测试了器件的退偏度，结果表明：只要器件的结构角适当，或者适当调节入射光束的截面大小，便可对某一单色线偏振光实现很好的退偏。     

Volterra积分方程和泛函微分方程的振动性

本文建立了Ｖｏｌｔｅｒａ积分方程和一阶泛函微分方程解的振动准则．     

锁相电子散斑系统

电子散斑干涉计量在变形量检测¹、无损探伤、振动分析^(2,3)等领域具有广泛的应用前景,目前它之所以未能实用化,最重要的原因就是该系统对环境的要求过高,特别是物体的振动和空气的扰动对测量结果影响很大,甚至会导致测量失败,因而国内外学者在不断寻找解决此问题的锁相技术。本文提出了一种简易的切实可行的锁相方法-光学锁相法,消除了物体的振动和空气扰动对电子散斑测量的影响。