Feedback nonlinear discrete-time systems

In this paper, we design an adaptive iterative learning control method for a class of high-order nonlinear output feedback discrete-time systems with random initial conditions and iteration-varying desired trajectories. An n-step ahead predictor approach is employed to estimate future outputs. The discrete Nussbaum gain method is incorporated into the control design to deal with unknown control directions. The proposed control algorithm ensures that the tracking error converges to zero asymptotically along the iterative learning axis except for the beginning outputs affected by random initial conditions. A numerical simulation is carried out to demonstrate the efficacy of the presented control laws.     

Intercalated PS/Na+‐MMT Nanocomposites Prepared by Ultrasonically Initiated In Situ Emulsion Polymerization

Summary: A new technique, ultrasonically initiated in situ emulsion polymerization, was employed to prepare intercalated polystyrene/Na⁺‐MMT nanocomposites. FTIR, XRD, and TEM results confirm that the hydrophobic PS can easily intercalate into the galleries of hydrophilic montmorillonite via ultrasonically initiated in situ emulsion polymerization, taking advantages of the multi‐effects of ultrasonic irradiation, such as dispersion, pulverization, activation, and initiation. Properly reducing SDS concentration is beneficial to widen the d‐spacing between clay layers. However, the Na⁺‐MMT amount has little effect on the d‐spacing of nanocomposites. The glass transition temperature of nanocomposites increased as the percentage of clay increased, although the average molecular weight of PS decreased, and the decomposition temperature of the 1obtained nanocomposites moves to higher temperature.

TEM of PS/Na⁺‐MMT nanocomposite prepared by ultrasonically initiated in situ emulsion polymerization.     

NDN-1型氮氧化物脱除催化剂的评价及应用

对NDN-1型氮氧化物脱除催化剂进行了实验室性能评价,并与进口催化剂A及国产催化剂B进行了比较,结果表明,NDN-1型催化剂的化学组成、结构、性能均优于进口催化剂A。介绍了该催化剂在南京帝斯曼东方化工有限公司工业应用的情况。     

沈阳含蜡油稀释三榨脱蜡新工艺

本文研制出一种新型的含蜡油稀释三榨脱蜡新工艺,该工艺对加工沈北减二线含蜡油十分有效,提高了石蜡质量与产量。     

加压下二氧化碳在二甲基甲酰胺中的溶解度研究

本文报道了二氧化碳在二甲基甲酰胺中的溶解度,实验温度分别为15、20、25、30、35、40、45℃,实验压力为207.21—1684.02kPa.并且提出一个考虑了过量熵的、用溶度参数表示的活度系数方程.     

Laboratory and field tests with the synthetic sex pheromone of threeMatsucoccus 1 pine bast scales

Matsunone, (2E,4E)-4.6,10,12-tetramethyl-2,4-tridecadien-7-one, is the primary sex pheromone ofMatsucoccus resinosae, M. thunbergianae, andM. matsumurae. The synthetic compound was tested in the laboratory and in field tests with all three species, and significantly more males responded to synthetic matsuone than to controls. The attraction of synthetic matsuone to males in field tests was not significantly different from that of virgin females at the same matsuone release rate. An analog of matsuone previously shown to be biologically active was also tested in the laboratory withM. resinosae andM. thunbergianae, and field tested withM. resinosae. The active analog required a dose approximately 100 times greater than matsuone to yield maximum laboratory bioassay response, and in field tests, attraction was not significantly different from controls at doses at which matsuone was significantly attractive.Homoptera: Coccoidea: Margarodidae.Deceased.     

PC/ABS共混体系的研究进展

综述了PC/ABS共混体系相结构的分析结果、增容技术以及影响PC/ABS合金性能的主要因素。     

塑料老化性能及使用寿命预测的新方法

提出了利用人工神经网络方法对塑料自然老化性能时间序列进行预测的方法，并建立了计算模型，在此基础上本方法也可对塑料使用寿命进行预测。实例计算证实了这种方法具有良好的精度。     

定量校准曲线法测定超高纯试剂丙酮中铁含量的研究

目前最常用的分析曲线法(标准曲线法、校准曲线法)、内标法、标准加入法等,对丙酮这类基体成分丰富的样品测定,其定量校准存在显著的系统误差.实验证实,通过保证标准系列中基体组成、浓度及酸度与待测样基本相同,来制作工作曲线进行定量校准(下称定量校准曲线法),能得到较为理想的结果.     

影响回转窑煅烧效果的因素分析

影响回转窑煅烧效果有多种因素，其中有些是不可控因素，有些是可控因素。不可控因素是指工艺线设备的先天性因素，如窑系统各组成部分，回转窑、预热器、分解炉等的设计参数，设备性能的不可变参数等，这些参数设计是否合理，设备选型和配置是否合理，有待系统运转后加以肯定，有缺陷的参数和设备设施只有通过技术改造加以完善和改进。