静电喷涂技术

本文介绍了静电喷涂的原理，静电喷涂设备和用途，操作工艺、应用效果及注意事项。     

静电喷涂技术在溶剂型涂料中的应用

介绍了静电喷涂的原理、工艺和静电漆料的配方设计原则，从理论和实践上证实了静电喷涂工艺具有较好的经济效益和环境效益。     

Data-driven asymptotic stabilization for discrete-time nonlinear systems

In this paper, we propose a data-driven feedback controller design method based on Lyapunov approach, which can guarantee the asymptotic stability of the closed-loop and enlarge the estimate of domain of attraction (DOA) for the closed-loop. First, sufficient conditions for a feedback controller asymptotically stabilizing the discrete-time nonlinear plant are proposed. That is, if a feedback controller belongs to an open set consisting of pairs of control input and state, whose elements can make the difference of a control Lyapunov function (CLF) to be negative-definite, then the controller asymptotically stabilizes the plant. Then, for a given CLF candidate, an algorithm, to estimate the open set only using data, is proposed. With the estimate, it is checked whether the candidate is or is not a CLF. If it is, a feedback controller is designed just using data, which satisfies sufficient conditions mentioned above. Finally, the estimate of DOA for closed-loop is enlarged by finding an appropriate CLF from a CLF candidate set based on data. Because the controller is designed directly from data, complexity in building the model and modeling error are avoided.     

Schistosome behavior in vitro

Schistosome adults attract each other in vitro and the attraction is chemically mediated. InSchistosoma mansoni adults, excretory-secretory (ES) products of worms of one sex attract worms of the opposite sex, and at least the lipophilic fraction is attractive. Intra- and interspecific attraction occurs inSchistosoma mansoni, S. japonicum, andS. haematobium adults. Current knowledge of schistosome behavior in vitro is reviewed.     

高阶非线性系统状态反馈抗饱和跟踪控制

针对参数未知的高阶非线性系统,提出了一种简单有效的反馈抗饱和控制方法,并进行了状态反馈抗饱和控制吸引域估计.利用反馈控制思想,借助于李亚普诺夫稳定性理论,设计出了相应的状态抗饱和反馈控制器,并借助于Matlab进一步求出了控制器的参数.将所设计的抗饱和控制应用于Duffing混沌系统,仿真结果验证了该控制方法的有效性.     

静电除尘器在磷石膏制硫酸联产水泥工程中的应用

阐述了磷石膏烘干脱水后,粉状半水石膏的收集、磷石膏煅烧窑气净化除尘均应选择静电除尘器的必要性。根据电除尘器处理介质(烘干尾气与水泥窑气)的特性及操作条件,介绍了设计选型要考虑防爆、结露等问题,并提出相应改进措施。     

Role of sex pheromone components in behavioral reproductive isolation betweenAutographa gamma (L.) and eitherTrichoplusia ni (Hübner) ORChrysodeixis chalcites (Esp.) (Lepidoptera: Noctuidae: Plusiinae)

The composition of theAutographa gamma sex pheromone was reexamined and only (Z)-7-dodecenyl acetate and (Z)-7-dodecenol were identified by capillary GC, GC-MS, and dimethyl disulfide derivatization and subsequent GC-MS analysis. The fatty acid content of the pheromone glands was also studied, and a series of saturated and unsaturated acids was identified. However, most of the related pheromonal compounds were not detected. The male response to the pheromone components was studied in a flight tunnel and compared with the response to calling females. The best synthetic baits evoked a response similar to that observed to the virgin females, but males spent significantly more time at calling females than at the synthetic baits. The preferred synthetic baits consisted of (Z)-7-dodecenyl acetate alone or of a blend with 5% (Z)-7-dodecenol. Increasing the relative amount of the alcohol caused a gradual reduction in male response, particularly in the last steps of the courtship sequence. The addition of the minor sex pheromone components of the sympatric Plusiinae species,Trichoplusia ni andChrysodeixis chalcites, to theA. gamma pheromone was also investigated in the flight tunnel. Some of these components exhibited a significantly antagonistic effect on theA. gamma male courtship behavior. The most potent antagonists were (Z)-5-dodecenyl acetate and (Z)-9-tetradecenyl acetate. The response ofA. gamma andT. ni males to conspecific and heterospecific females was also compared in the flight tunnel. WhereasA. gamma males were attracted only to their conspecific females, a small percentage ofT. ni males were also attracted toA. gamma females and 11% performed the whole courtship sequence.Contribution from the Agricultural Research Organization (ARO), No. 3459-E, 1992 series.     

简单电力系统暂态电压稳定的直接分析法

对综合负荷采用三阶感应电动机并联恒阻抗动态模型,构建了简单电力系统暂态电压稳定分析的微分代数方程组(DAE)模型,并采用非线性动力系统理论计算系统故障后稳定平衡点的吸引域。针对采用牛顿法求取系统不稳定平衡点碰到的初值选取问题,通过对综合负荷感应电动机部分采用其稳态等值电路来求得不稳定平衡点;并采用将非线性系统化为规范型线性系统的方法求得系统故障后稳定平衡点的吸引域边界;进而只须仿真得到故障切除时刻系统的状态即可判断系统能否保持电压稳定。通过与系统全故障过程仿真结果的比较验证了本文方法的正确性。     

两种电子温度等离子体系统中的电子束流不稳定性

在一个包含两种不同温度电子的等离子系统中,用一维全粒子模拟模型研究电子束流不稳定性.在模拟模型中,考虑了离子与电子的实际质量比与将离子看成是静止不动的背景离子相比,在一维全粒子模拟中噪声要低,并且由于离子的原因电子束流不稳定性变弱.由于电子速度分布出现的平台和一维全粒子模拟模型中电子洞的形成使得孤波产生,在模拟中该孤波沿着电子束流的反方向传播.     

高热稳定性二阶非线性光学自组装薄膜的制备研究

采用偶氮型聚阴离子PAZO与感光型聚阳离子重氮树脂DR进行层层静电自组装,制备非线性光学薄膜,并采用紫外可见光谱跟踪成膜过程。经过紫外光照,层间的静电相互作用转化为共价键连接而形成稳定的多层膜。对制备的DR/PAZO多层组装膜进行的二阶非线性光学性质、热稳定性及抗溶剂刻蚀能力的研究表明,膜层具有较明显的SHG信号,同时曝光后的膜层比未经曝光的膜层表现出了更好的热稳定性和抗溶剂稳定性。