Effect of the oxide support on the propane ammoxidation with Sb–V–O-based catalysts

The role of Nb₂O₅ and γ-Al₂O₃ oxide supports on the ammoxidation of propane on supported mixed Sb–V oxide at different Sb+V surface coverages is studied. Sb and V oxide species on alumina and on niobia support show different structural features that reflect in different performance during the ammoxidation of propane to acrylonitrile. Niobia-supported catalysts are much more selective to acrylonitrile than alumina-supported ones. Alumina interacts weakly with the supported oxides while niobia forms new phases through solid state reactions with the supported oxides during catalytic operation that must account for its higher selectivity values towards acrylonitrile and higher specific rate of acrylonitrile formation per vanadium site.     

减振器在自导系统结构设计中的应用

通过对减振器结构设计的理论分析，建立了减振器的数学模型，同时通过设计的模拟装置对减振效果进行了实测，效果良好。     

共面波导有限金属厚度效应的研究

用保角变换法对共面波导金属厚度效应进行了理论分析，编制了相应的计算机程序，给出了数值解，并对此进行了多元曲线拟合，导出了考虑金属厚度后的形状比k、有效介电常数、特征阻抗、损耗的闭定表达式。用此修正表达式求得特征阻抗及损耗的数值解，并与K．C．格普塔的修正值及实验测量值进行了详细比较，结果表明此修正公式与实验值相符较好。     

分析矩形光波导损耗的简易方法

利用有效折射率和修正的有效折射率方法对矩形光波导的损耗作了简单有效的分析，并且计算出了纵向传播系数和衰减系数的大小。     

邻苯二甲酸酯鼓泡生物降解

该课题测试了邻苯二甲酸酯类化合物的鼓泡生物降解行为。结果表明，邻苯二甲酸酯的降解速率常数（kb)与其烷基链长度之间存在良好的相关性，kb=0.0009x^2-0.019x 0.1123，相关系数r=0.9906；浓度超过500mg/L时，邻苯二甲酸二乙酯可抑制自身的生物降解；中间产物邻苯二甲酸浓度超过50mg/L时，也对邻苯二甲酸二乙酯的生物降解有明显的抑制作用。     

Similarity retrieval of iconic image database

The perception of spatial relationships among objects in a picture is one of the important selection criteria to discriminate and retrieve the images in an iconic image database system. The data structure called 2D string, proposed by Chang et al., is adopted to represent symbolic pictures. The 2D string preserves the objects' spatial knowledge embedded in images. Since spatial relationship is a fuzzy concept, the capability of similarity retrieval for the retrieval by subpicture is essential. In this paper, similarity measure based on 2D string longest common subsequence is defined. The algorithm for similarity retrieval is also proposed. Similarity retrieval provides the iconic image database with the distinguishing function different from a conventional database.     

抓住机遇,正确处理通信发展中的若干关系问题

本文分析了我国通信业面临的国内外形势，指出为加速发展我国的通信事业应抓住机遇，正确处理好几个关系问题。     

O—O数据模型中实体联系的表达方法

具有对实体和实体间联系的描述能力，是数据库的基本，吼是对数据库进逻辑设计的基本出发点。Ｏ－Ｏ数据模型不具备显式描术这实体联系的手段。且优于关系模型。