干旱生态脆弱区生态功能区划——以新疆策勒县为例

本文以位于西北内陆干旱区的典型生态环境脆弱区域为研究靶区,利用GIS和RS技术,在生态环境现状评价的基础上,通过对相关评价因子进行赋值,运用加权指数法、评价指标体系等进行分级.然后对生态环境敏感性、生态服务功能重要性进行评价,依据综合敏感性和重要性评价结果,按照其地理位置和生态特征分为1个一级生态区、3个二级生态亚区和11个生态功能区.生态功能区的划分,有利于明确重要生态功能保护区的空间分布,为今后的生态保护措施和产业发展方向提供了依据.     

基于BP神经网络模型模拟塔里木河下游潜水埋深变化——以英苏断面C5井为例

本文以塔里木河下游英苏断面350m处C5井为研究对象,分析了影响下游英苏断面的潜水埋深影响因素,通过三层BP神经网络模型模拟了潜水埋深变化．以Matlab7．0为工作平台,将2000．7-2008．12期间的英苏C5井的步长为3个月数据资料作为一个样本,选取每个样本的输水量、输水持续天数、上季度该井的潜水埋深平均值作为模型输入量,输出量为相应的C5井的本季度的潜水埋深平均值,建立3—11-1的BP神经网络模型,模拟了C5井潜水埋深．结果表明,网络模拟相对误差小于5％,模型具有较高的精度．通过BP模型模拟潜水埋深,为塔河下游生态恢复和水资源决策提供一定的依据．     

介质阻挡放电不同模式下的光电信号比较

利用水电极介质阻挡放电装置,分别在大气压空气和氩气中得到随机放电丝、六边形斑图和均匀弥散三种不同模式的放电。通过比较三种不同模式下的光信号和电流信号,研究介质阻挡放电中光信号和电流信号的关系。研究结果表明,当放电信号较大时,光信号与电流信号存在着一一对应关系。由于电流信号包含放电电流和位移电流,因此当放电电流很小时,放电电流信号淹没在位移电流中。在这种情况下,只能通过研究光信号的波形来研究相应的放电情况。除此之外,研究了单个放电丝的光信号,发现光信号测量可以实现对放电过程的空间分辨测量。结果表明分析光信号是一种很好的研究介质阻挡放电动力学过程的方法。     

模拟氧化凝胶去污废液的预处理初步研究

为了探索氧化凝胶二次废液的预处理方法,了解二次废液的基本特征,开展了模拟氧化凝胶去污废液的预处理初步研究。采用过氧化氢处理模拟氧化凝胶废液中残余Ce(Ⅳ),以中和、过滤法对废液进行处理,并对模拟废液中沉淀物及其粒径分布进行测定。结果表明:利用过氧化氢处理模拟氧化凝胶去污废液中残余的Ce(Ⅳ),其反应迅速、完全;当调节模拟废液pH为9时,模拟废液中湿沉淀量为88.4 g/L,干沉淀量为18.8g/L,沉淀物的粒径主要集中在1.783～10μm。     

Study on the transition from filamentary discharge to diffuse discharge by using a dielectric barrier surface discharge device

Discharge characteristics have been investigated in different gases under different pressures using a dielectric barrier surface discharge device. Electrical measurements and optical emission spectroscopy are used to study the discharge, and the results obtained show that the discharges in atmospheric pressure helium and in low-pressure air are diffuse, while that in high-pressure air is filamentary. With decreasing pressure, the discharge in air can transit from filamentary to diffuse one. The results also indicate that corona discharge around the stripe electrode is important for the diffuse discharge. The spectral intensity of N电介质 表面放电 扩散放电 发射光谱学dielectric barrier surface discharge, diffuse discharge, optical emission spectroscopyProject supported by the National Natural Science Foundation of China (Grant Nos 10575027 and 10647123), the National Science Foundation of Hebei Province, China (Grant No A2007000134), the Education Department of Hebei Province, China (Grant No 2006106),2006-10-24Discharge characteristics have been investigated in different gases under different pressures using a dielectric barrier surface discharge device. Electrical measurements and optical emission spectroscopy are used to study the discharge, and the results obtained show that the discharges in atmospheric pressure helium and in low-pressure air are diffuse, while that in high-pressure air is filamentary. With decreasing pressure, the discharge in air can transit from filamentary to diffuse one. The results also indicate that corona discharge around the stripe electrode is important for the diffuse discharge. The spectral intensity of N＋ （391.4nm） relative to N2 （337.1 nm） is measured during the transition from diffuse to filamentary discharge. It is shown that relative spectral intensity increases during the discharge transition. This phenomenon implies that the averaged electron energy in diffuse discharge is higher than that in the filamentary discharge.