4‐chloro‐3‐methylphenyl methacrylate copolymers with 2,4‐dichlorophenyl methacrylate: Synthesis,characterization, and antimicrobial activity

4‐Chloro‐3‐methylphenyl methacrylate (CMPM) and 2,4‐dichlorophenyl methacrylate (2,4‐DMA) were synthesized by reacting methacryloyl chloride with 4‐chloro‐3‐methylphenol (CMP) and 2,4‐dichlorophenol (2,4‐DP), respectively. Homo and copolymers of CMPM and 2,4‐DMA were obtained from different monomer feed ratios, using 2,2′‐azobisisobutyronitrile as initiator in toluene at 70°C. IR‐spectroscopy was employed to characterize the resulting homo and copolymers. Copolymer compositions were determined by ultraviolet (UV) spectroscopy. Fineman–Ross method was used to calculate the reactivity ratios of the monomers. Average molecular weight and polydispersity index were obtained by gel permeation chromatography (GPC). Thermogravimetric analyses (TGA) and differential thermal analysis (DTA) of copolymers were carried out under a nitrogen atmosphere. Antimicrobial effects of the homo and copolymers were also investigated for various microorganisms such as bacteria, fungi, and yeast. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100:439–448, 2006     

基于神经网络预测误差修正的广义预测控制

针对建模误差对预测控制的影响,提出一种基于神经网络预测误差修正的广义预测控制算法.被控对象采用递推最小二乘法(RLS)辨识其线性模型;预测误差由前馈神经网络进行建模,并用Powell快速优化方法训练网络.该方法无需预先离线训练神经网络,即可投入闭环控制,并具有理想的稳定性、跟踪性能和鲁棒性.仿真结果表明该算法能够有效地控制复杂系统.     

Simultaneous generation and correlation of complete sets of generalized pairwise complementary sequences

New coding schemes are increasingly being developed to adapt multisensor and communication systems to the requirements of the current technological environment. In some cases, the practical implementation of these schemes involves a great amount of signal processing operations. In order to achieve and make suitable their use in different platforms, efficient algorithms are required to process coding. In the last years, a new kind of complementary sequences, known as Generalized Pairwise Complementary sequences, has been proposed. These sequences provide high noise immunity when they are applied to multiuser systems, as well as a low cross‐correlation, which is convenient in those applications. The aim of this paper is to propose optimized generation and correlation architectures for Generalized Pairwise Complementary sequences that would allow to process a complete set using a reduced amount of operations. An analytical demonstration is provided, with a final comparison to evaluate the reduction with regard to other algorithms. Copyright © 2015 John Wiley & Sons, Ltd.     

桉木APMP制浆过程浆中残余木素分子量的变化

利用凝胶渗透色谱法和元素分析法测定了尾叶桉酶解木素在APMP制浆及漂白过程的分子量变化。研究结果表明：由于HOO-的特殊作用,制浆及漂白之后,浆中剩余木素的平均分子量相对有所增大。     

基于极点配置的稳定广义预测控制算法

推导了广义预测控制的状态空间结构,提出了一种稳定的广义预测极点配置算法;可保证广义预测控制系统的闭环稳定性     

Graft copolymers of lignin from straw with 1‐ethenylbenzene: Synthesis and characterization

The synthesis of copolymers between lignin from steam‐exploded straw and 1‐ethenylbenzene is described. Beforehand, lignin from steam‐exploded straw was fully characterized by using elemental analysis, ultraviolet spectroscopy, gel permeation chromatography (GPC), Fourier transform infrared (FTIR), and both ¹H and ¹³C nuclear magnetic resonance (NMR) spectroscopy. Using a previously described procedure utilizing calcium chloride and hydrogen peroxide as reagents the synthesis of the copolymers was performed. FTIR of the copolymers showed the presence of both lignin and polystyrene. GPC analysis showed the presence of a fraction with high molecular weights. These results were confirmed from both viscosity data and differential calorimetry. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 72–79, 2001     

APPLICATION OF ADAPTIVE PREDICTIVE CONTROL TO A SHAKER CONVEYOR FOR TRANSPORTATION OF PLASTIC BEADS

After having briefly portrayed the basic principles of predictive control, three adaptive predictive control algorithms–the GPC algorithm and two new modifications of it proposed by the authors, called the MGPC (modified GPC) algorithm and the DGPC (direct GPC) algorithm—will be discussed. The main disadvantage of the GPC algorithm, namely the noise sensitivity, will be highlighted, when the real-time application to a plant with variable dead-time, a shaker conveyor system for transportation of plastic beads, will be studied. Both new algorithms proposed here show good behaviour in reducing the computational burden and achieving a better disturbance rejection than the direct application of the GPC algorithm. © 1997 by John Wiley & Sons, Ltd.     

基于BP神经网络变参数设计的广义预测控制

针对广义预测控制算法中控制参数整定困难这一缺陷,提出了一种基于BP神经网络变参数设计的广义预测控制算法,实现了广义预测控制中的输出柔化系数α和控制增量加权系数λ的在线调整。仿真结果表明,该算法无论在跟踪性能、控制精度及鲁棒性上,均优于固定参数设计的广义预测控制算法,并对干扰有一定的抑制作用。     

凝胶色谱-固相萃取-气相色谱-串联质谱法测定水产品中9种三嗪类除草剂

建立了水产品中9种三嗪类除草剂的凝胶色谱 固相萃取-气相色谱-串联质谱(GPC-SPE-GC-MS/MS)分析方法。样品采用乙酸乙酯提取,凝胶渗透过滤,石墨化碳串联氨基柱净化,选择离子监测模式测定,外标法定量。结果表明：扑灭津、阿特拉津、特丁津、西玛津、扑草净在1.0~50.0 μg/L范围内线性良好,检出限均为1.0 μg/kg,在1.0~10.0 μg/kg添加水平,平均回收率为86.3%~119%,相对标准偏差为5.11%~10.1%;环草津、莠灭净、特丁净、西草净在2.0~100.0 μg/L范围内线性良好,检出限均为2.0 μg/kg,在2.0~20.0 μg/kg添加水平,平均回收率为87.6%~112%,相对标准偏差为5.27%~9.56%。该方法稳定、可靠,适用于水产品中9种三嗪类除草剂的同时测定。     

广义预测控制在泵池回路中的应用

广义预测控制融合了预测控制和自适应控制的优点,是自适应控制中另一类型的预测控制方法,易于在线估计参数,以实现自适应控制。磨矿生产中,泵池回路控制是一个复杂的慢时变动态过程控制,具有很强的非线性、强耦合、大滞后、强干扰等特性,而传统的PID控制算法很难达到理想的控制效果和较高的自动投运率。为此,针对泵池控制回路的特点,提出基于模型性能指标和加权系数的广义预测控制算法,建立了泵池控制模型,并于2010年将该模型应用于金川选矿厂磨矿生产的泵池回路控制。实际工业应用表明,这种广义预测控制具有较强的适应性和较高的控制精度,控制效果优于传统PID控制算法。