基于CMFS-MIC特征选择的跳频电台个体识别方法

针对跳频电台细微特征集中存在冗余特征等导致电台识别时存在计算量大、识别准确率低等问题,提出了一种基于CMFS-MIC特征选择的跳频电台个体识别方法。首先计算采集到的各个跳频电台信号样本的细微特征集,然后采用关联信息熵度量特征子集的组合效应,兼顾考虑特征间的关联关系和冗余关系对各个特征进行降序排序。在此基础上,采用最大信息系数度量的近似马尔可夫毯方法删除冗余特征,实现对特征子集进行优化和降维。最后,设计了投票组合分类器实现对4部跳频电台信号的识别。仿真结果表明,本文算法具有更高的分选识别率。     

基于最大偏差相似性准则的BP神经网络短期电力负荷预测算法

针对企业电力负荷随机性强、稳定性低、预测精度不理想等问题,提出了一种基于最大偏差相似性准则的BP神经网络短期电力负荷预测算法。首先对最大偏差相似性准则算法进行修改,并提出使用预测日的负荷特征向量与最大偏差相似性准则算法聚类之后的类中心负荷特征的距离来确定预测日的相似日类别;然后将聚类后的相似日类别负荷数据作为BP网络的训练数据,输出预测日起始的连续三天96整点负荷值。实验表明,该方法提出的短期电力负荷预测方法在精度和网络训练时间上都有较大的提升,具有较高的有效性和实用性。     

Time-of-flight studies on catalytic model reactions

Time-of-flight spectroscopy (TOF) and REMPI-TOF (resonance enhanced multi-photon ionization-TOF) were applied to measure the angular and translational energy distribution, as well as the internal state resolved energy distribution of desorption and reaction products on some model systems. Desorption of hydrogen and deuterium from clean and modified Pd(111) surfaces was studied, where the palladium sample was part of a permeation source. Water formation by reaction of oxygen with hydrogen on palladium was investigated by using different types of hydrogen supply: molecular H₂ exposure and atomic H exposure from the gas phase, as well as H exposure by permeating hydrogen. Vanadium oxide nanostructures on Pd(111) were prepared and the influence on D₂ desorption and D₂O production was investigated with the permeation technique. Additionally, deuterium desorption from sulfur and oxygen covered V(111) and V(100) surfaces was studied by TOF and REMPI-TOF spectroscopy. From the TOF spectra information concerning the reaction and desorption dynamics (activation barriers) could be gained.     

YL-1OO型自动加药装置在乙烯循环水场的应用

介绍了国产YL-100型自动加药装置功能及其在中国石化茂名石化乙烯工业公司乙烯循环水场的应用情况,结果表明其运行平稳,总磷测试数据可靠,可达到循环水自动加药控制的目的。     

用工业废碱水处理反渗透法高含盐排放浓水

反渗透处理装置排放的浓水含盐量很高，如果不经处理直接排放势必对周围环境造成污染和水的浪费，氧化铝生产工艺废水中含有大量的碳酸钠、苛性碱等碱类物质，pH值达到13左右，回水量约2000m^3／h，用这些废水和反渗透浓水混合进行软化处理，降低浓水中的钙镁离子含量，并对难去除的硫酸盐进行稀释降低浓度，回用到蒸发循环水系统作为补充用水、氧化铝生产部分工艺用水、设备冷却用水，达到浓水回收再利用的目的。该方案实施后效果十分显著，回收反渗透浓水约60m^3／h，减少污水系统补充新水，降低生产用水费用约每年176万元。     

超临界水中NaCl无限稀释扩散系数的研究

The molecular dynamics(MD) was employed to simulate the diffusion coefficient of sodium chloride at infinite dilution in supercritical water from 703.2K to 763.2K and from 30 MPa to 45 MPa ,Based on the simulated data and the Patel-Teja(PT) equation of state and the Liu-Ruckenstein equation,an equation for calculating the diffusion coefficient of NaCl at infinite dilution in supercritical water is proposed,Both the agreement between the simulated and correlated data,and that between the simulated and predicted data of diffusion coefficients for NaCl in supercritical water ranging from 703.2K to 803.2K and from 25 MPa to 50MPa show that this equation is applicable for calculation of diffusion coefficients.     

Electrochemical ferrate generation for waste water treatment using cast irons with high silicon contents

This paper deals with the electrochemical preparation of ferrate in 15 M NaOH media, with a view to treatment of waste waters. Grey cast irons with high silicon contents were shown to allow current yields in the range 20–40% depending on the applied current density, up to 34 mA cm^–2. Ferrate solutions with contents up to 0.08 M could be produced in a divided cell of simple design, and provided with flat or packed-bed electrodes. Deactivation of the anode surface was shown to be of moderate significance for hour-long runs. The ferrate produced was tested for treatment of industrial liquid wastes: coagulation efficiency of the suspended matter was comparable with that of an electrocoagulation process with sacrificial Al anodes. The potential of waste water treatment by addition of ferrate is discussed.     

臭氧生物活性炭工艺处理饮用水时各阶段的特点

论述了臭氧生物活性炭工艺中的臭氧发生系统、臭氧尾气处理系统、臭氧预氧化及后氧化、生物活性炭滤池各阶段的应用现状及特点。指出：臭氧发生系统采用氧气为原料来提高臭氧浓度，臭氧质量分数可达6％左右；由于电加热分解臭氧尾气反应速度快，可在1．5～2s内完全分解，应是今后自来水厂臭氧尾气处理技术应用的重点；臭氧预氧化一般采用静态混合器或水射器单点投加，投加量为1～2mg／L，接触时间为1～4min；臭氧后氧化一般采用微孔曝气盘以微气泡的形式多点投加，水中臭氧余量控制在0．2～0．4mg／L，接触时间大于10min；生物活性炭滤池对苯类化合物和相对分子质量在500～1000范围内的腐殖质去除率达70％～86．7％。     

D.s.c. investigation of the states of water in poly(vinyl alcohol-co-itaconic acid) membranes

The state of water in water-swollen poly(vinyl alcohol-co-itaconic acid) membranes, having various water contents from 0.31 to 0.83, was investigated by d.s.c. measurements and compared with those in water-swollen poly(vinyl alcohol) membranes. The amount of freezing water in the membranes was estimated by use of a relationship between the phase transition temperature and the enthalpy of the crystallization of supercooled water. The melting temperature of the water in the membranes immersed in urea and NaCl 0–2 mol l^?1 aqueous solutions was also determined by d.s.c. analysis. The present study proposes a method for estimating the solubilities of urea and NaCl in both of the freezing and the non-freezing water using the melting point depression of the freezing water in the membranes immersed in the solute solution.     

一体化锅炉水处理剂的制备及性能研究

利用自制SW-56共聚物，复配有机磷酸盐和焦亚硫酸钠除氧剂及消泡剂，成功制备XF-4一体化锅炉水处理剂。对XF-4锅炉水处理剂的阻垢、缓蚀进行了试验研究，表明其具有优良的阻垢能力，可以明显抑制热水锅炉积垢现象；加入改性除氧剂能降低锅炉水中溶解氧的含量，使腐蚀控制较理想；配方中的消泡剂组分可防止锅炉水表面起泡，抑制高悬浮物下的携带作用。