油水驱动半正定问题迎风混合元格式及其数值分析

研究了不可压缩油水两相渗透流驱动问题.在扩散矩阵仅是半正定的假设条件下,提出了迎风混合元方法.混合元方法近似压力方程,饱和度方程的对流项用Godunov迎风格式来处理,扩散项则用推广的混合元来逼进,并推导出格式的误差估计.此种格式的优越性表现在两个方面:首先是饱和度方程的扩散矩阵仅是半正定的;二是摒弃了特征格式所限制的周期性条件,更适用于实际问题.     

高压氮气亚纳秒开关放电特性实验研究

 利用幅值约220 kV、脉宽约4 ns的高压纳秒脉冲源，对高压氮气亚纳秒气体开关放电特性进行了实验研究。实验结果表明：当气压在3~10 MPa间变化，间隔距离在0.6~1.2 mm间变化时，氮气间隙击穿电压随气压和间隙距离的增大而增大，并随气压的增大略呈饱和趋势,最高击穿电场约为2 MV/cm。开关输出电压波形的上升时间变化范围为145~190 ps，该上升时间随气压、击穿电场以及间隙距离增大而减小。     

量子Euclid空间上的实结构和微分运算

本文讨论量子(q形变)Euclid空间上的实结构问题.在c*代数的框架内,通过区分左右微商运算,我们在N维量子Euclid 空间上构造了一种与微分运算相协调的实结构.这种构造方法也适用于量子Minkowski 空间的情况。     

Neural Approach for Calculating Permeability of Porous Medium

Permeability is one of the most important properties of porous media. It is considerably difficult to calculate reservoir permeability precisely by using single well-logging response and simple formula because reservoir is of serious heterogeneity, and well-logging response curves are badly affected by many complicated factors underground. We propose a neural network method to calculate permeability of porous media. By improving the algorithm of the back-propagation neural network, convergence speed is enhanced and better results can be achieved. A four-layer back-propagation network is constructed to effectively calculate permeability from well log data. Spontaneous potential, resistivity of deep lateral log, resistivity of micro-gradient log, resistivity of micro-normal log, Interval transit time of acoustic log and resistivity of shallow lateral log are selected as the inputs, and permeability is selected as the output. There are 35 and 40 units used in the two hidden layers, respectively. During the training course, the correlation coefficient between the calculated permeability and the standard pattern is as high as 0.9937, the average absolute error between them is 0.046μm^2 and the average relative error is only 1.93%. for practical applications, the average relative error between the calculated permeability and actual permeability is also as low as about 10.0%.     

纳米ZnO胶体可见发射机制的研究

关于ZnO可见发射机制的讨论目前尚无定论。本文研究了不同颗粒尺寸的纳米晶ZnO胶体的发射性质,观测到两个发射带,其中之一是激子发射,另一个是可见发射;发现两个发射带的峰值能量之间存在线性关系,并由此提出了可见发射机制是来自导带的电子到深陷阱的跃迁。     

新模式热电联产系统:联产供热的一个发展

1前言经济的迅猛发展，能源与水源的供需矛盾的突出，环保形势的严峻要求用能的“文明化”。文明用能应是跨世纪和新世纪用能战略的基本原则。文明用能的一个极重要方面就是对热能的文明利用问。热电联产是热能文明利用不可替代的途径。本文提出一种热电联产的新模式，旨在通过这种模式把联产供热规模化，大幅度地节约能源和水资源，减轻电能与热能的生产对环境的不利影响。最近中央提出的可持续发展战略，应成为我们今后技术研究的一个指导性方针。节约能源、水源和保护环境是这一战略的重要组成部分。在世界范围内，对节约资源保护环境问…     

Preparation of Molecular Sieve Catalyst and Application in the Catalytic Oxidation Treatment of Waste Water

Citric acid is an important additive in foods, cosmetics, medicine and so on, but it discharges about 10 ton of factory effluent when 1 ton of citric acid is produced. The COD of the factory effluent is near 20000 mg/L. The treatment of citric acid factory effluent is a serious problem in environmental chemistry. It is found that molecular sieve support metal complexes have high catalytic activity in aerobic oxidation of alkene [1,2]. In this paper, a kind of molecular sieve catalyst was prepared. The catalyst was used for the treatment of citric acid factory effluent by method of catalytic oxygen oxidation.     

空中交通流量管理中的改航策略研究

针对在恶劣天气下出现的大规模航班延误情况,根据机场和航路段的动态容量约束,建立了改航策略模型,并提出求解该模型的有效算法.选择全国航班时刻表进行仿真,仿真结果表明:该模型提供了在恶劣天气下更安全、更经济的航班改航策略,可为战术级流量管理提供辅助决策.     

X射线光刻技术的进展及问题

Ｘ射线光刻是一种能满足下世纪初超大规模集成电路（ＶＬＳＩ）生产的深亚微米图形加工技术。论述了这种光刻技术的发展历史及近年来的主要进展。重点讨论了在Ｘ射线源、接近式曝光和全反射投影曝光等方面取得的成就与存在的问题。展望了这种技术的发展前景