高效液相色谱法测定中党参中4种黄酮类物质的含量

黄酮类化合物广泛存在于中药等植物体中,对人体肿瘤、衰老、心血管等退行性疾病的治疗和预防有重要意义~([1]).目前测定黄酮类物质的方法很多~([2～5]),本研究采用高效液相色谱法测定了党参中芦丁、曲克芦丁、黄芩苷和槲皮素4种黄酮成分的含量.方法简单易行,结果准确可靠.     

镧掺杂的介孔分子筛的合成及其光学性能研究

以十六烷基三甲基溴化铵(CTAB)为表面活性剂,正硅酸乙酯(TEOS)为硅源,采用水热晶化法,合成了镧掺杂的MCM-41介孔分子筛。通过X射线衍射(XRD)、傅里叶变换红外(FTIR)光谱、透射电镜(TEM)、紫外-可见(UV-Vis)光谱等测试手段对其孔结构和镧原子的存在状态进行了表征。XRD和TEM结果表明,合成样品具有典型的二维六方有序介孔结构,样品的傅里叶变换红外光谱和紫外-可见光谱表明镧被成功的引入到介孔骨架中。     

Nonlinear consensus protocols for multi-agent systems based on centre manifold reduction

Nonlinear consensus protocols for dynamic directed networks of multi-agent systems with fixed and switching topologies are investigated separately in this paper. Based on the centre manifold reduction technique, nonlinear consensus protocols are presented. We prove that a group of agents can reach a β-consensus, the value of which is the group decision value varying from the minimum and the maximum values of the initial states of the agents. Moreover, we derive the conditions to guarantee that all the agents reach a β--consensus on a desired group decision value. Finally, a simulation study concerning the vertical alignment manoeuvere of a team of unmanned air vehicles is performed. Simulation results show that the nonlinear consensus protocols proposed are more effective than the linear protocols for the formation control of the agents and they are an improvement over existing protocols.     

Automatic generation of min-weighted persistent formations

This paper researched into some methods for generating min-weighted rigid graphs and min-weighted persistent graphs. Rigidity and persistence are currently used in various studies on coordination and control of autonomous multi-agent formations. To minimize the communication complexity of formations and reduce energy consumption, this paper introduces the rigidity matrix and presents three algorithms for generating min-weighted rigid and min-weighted persistent graphs. First, the existence of a min-weighted rigid graph is proved by using the rigidity matrix, and algorithm 1 is presented to generate the min-weighted rigid graphs. Second, the algorithm 2 based on the rigidity matrix is presented to direct the edges of min-weighted rigid graphs to generate min-weighted persistent graphs. Third, the formations with range constraints are considered, and algorithm 3 is presented to find whether a framework can form a min-weighted persistent formation. Finally, some simulations are given to show the efficiency of our research.     

Generalized LMI-based approach to global asymptotic stability of cellular neural networks with delay

A global asymptotic stability problem of cellular neural networks with delay is investigated. A new stability condition is presented based on the Lyapunov-Krasovskii method, which is dependent on the amount of delay. A result is given in the form of a linear matrix inequality, and the admitted upper bound of the delay can be easily obtained. The time delay dependent and independent results can be obtained, which include some previously published results. A numerical example is given to show the effectiveness of the main results.     

可折叠航天结构展开动力学分析

以欧拉参数为广义坐标（准坐标）,相对角速度和相对移动速度为广义速率,采用Ｋａｎｅ方程的Ｈｕｓｔｏｎ形式建立多体系统的运动力学方程。由伪上三角分解求约束Ｊａｃｏｂｉ矩阵的正交补阵,约简约束力,从而将运动方程由微分几何方程（ＤＡＥ）变为常微分方程（ＯＤＥ）,并由Ｇｅａｒ法对ＯＤＥ积分求出运动历程。最后给出一伸展臂数值分析算例。     

抑制型离子色谱法测定白酒中的F-、Cl-、NO2-、H2 PO4-、NO3-

用抑制型离子色谱法测定白酒中的F^-、Cl^-、NO2^-、H2PO4^-、NO3^-。流动相为4mmol／LNa2CO3—3 mmol／LNaHCO3混合溶液,流速为1．5mL／min,进样量为0、5mL,在最佳色谱条件下,5种无机阴离子10min内实现基线分离。F^-、Cl^-、NO2^-、H2PO4^_、NO3^-的检出限分别为0、008、0．012、0、030、0．068、0．077mg／L。测定结果的相对标准偏差分别为1．86％、1．30％、2．06％、1．82％、1．50％,回收率分别为108．0％、94．0％、101．0％、98．7％、94．4％。     

面包酵母在催化不对称合成中的应用

介绍了当前国内外在以面包酵母为催化剂不对称催化合成手性化合物的研究情况,重点介绍了面包酵母催化各类潜手性羰基的不对称还原、潜手性碳一碳双键的不对称加成和碳一碳键形成的反应情况,讨论了各种提高酵母催化不对称合成反应立体选择性的方法,对酵母催化不对称合成有关生物学方面的研究进行了简单的介绍。     

大型结构变形监测摄像测量研究进展

桥梁、隧道、舰船等大型结构变形的全场、高精度、动态测量,是其动态性能实验和质量监测的基本要求。摄像测量具有非接触、高精度、可测点多、实时动态测量等特点,在大型结构的变形监测方面有独特的优势。本文介绍了作者所在科研团队近年来利用摄像测量技术在大型结构变形监测方面的研究新成果和典型应用,包括提出位移传递像机串联网络摄像测量方法与技术,用于自动监测高速铁路、隧道等大型结构的路基沉降;研制天线基座变形摄像测量系统,实时、连续、长时间测量我国远望号测量船的天线基座变形等。     

Consensus protocol for multi-agent continuous systems

Based on the algebraic graph theory, the networked multi-agent continuous systems are investigated. Firstly, the digraph （directed graph） represents the topology of a networked system, and then a consensus convergence criterion of system is proposed. Secondly, the issue of stability of multi-agent systems and the consensus convergence problem of information states are all analysed. Furthermore, the consensus equilibrium point of system is proved to be global and asymptotically reach the convex combination of initial states. Finally, two examples are taken to show the effectiveness of the results obtained in this paper.