Synthesis of Furano[3,2-c]- and Pyrano[3,2-c]quinolines upon Imino Diels-Alder Reactions Initiated by Nitrosonium （NO^＋）

Efficient nitrosonium （NO＋）-initiated aza-Diels-Alder reactions of N-arylimines with 2,3-dihydrofuran or 3,4-dihydro-2H-pyran allowed access to furano[3,2-c]- or pyrano[3,2-c]quinolines. A mixture of cis and trans-quinoline isomers was obtained in various ratios and yields.     

江西省社会发展评价指标体系的建构及对各地市的评价

本文介绍了由本省省情构建的一套江西省社会发展评价指标体系,并用系统工程和计算机技术对全省11地市1988至1990年三年间的社会发展进行综合评述。     

Momental solution of spherical shells with variably nonlinear section under normal pressure

In this paper,spherical shell with variably nonlinear section that is widely used ineingineering and its equation of the section,δ=δ_0(1 βφ)~2)is analysed to momentalproblem.The Euler solutions of internal forces are obtained under normal pressure.     

BCK-代数的几个计数定理

本文推广了文献中的有限BCK-代数子代数个数估计定理,给出了任意BCK-代数的子代数个数下界的一个估计。对于n阶BCK-代数和n阶半直接既约交换BCK-代数,本文分别给出了其子代数个数下界的较具体的表达公式。另处我们还讨论了互不同构的n阶BCK-代数的个数的下界值的估计问题。     

球形扁壳超临界变形的步进求和计算

本文用步进求和法计算了球形扁壳第二类失稳问题,在球扁壳超临界变形计算上给出了优于一级近似结果,解决了该问题无法求二级近似解的困难.算例表明步进求和法收敛于二级近似解.     

几种光学图象相位加密方法的比较

本文分析比较了多种实现光学图象相位加密的方法,发现不同方法获得的加密图象有不同类型的噪音分布.无论加密相位是随机相位模板、浑沌序列的相位列阵,还是用相位重构迭代算法计算的结果,它们都能起到加密图象的功能.解密图象的质量或被相关识别的能力与解密过程中所使用正确解密相位的不同部分以及高低频分量多少有关,且其依赖程度是由不同的加密方法自身决定.     

FeO4^2—与ClO^—共存体系的氧化还原滴定分析法

在重铬酸钾容量法测Ｆｅ＾２＋和硫酸亚铁铵容量法测Ｃｒ（Ⅳ）的基础上,提出ＦｅＯ４＾２－与ＣｌＯ＾－共存体系的氧化还原滴定分析法。该方法实用、可靠、对样品分析,结果令人满意。     

负载型La0.8Sr0.2MnO3燃烧催化剂的载体效应

用浸渍法制备负载型Ｌａ_（０．８）Ｓｒ_（０．２）Ｍｎｏ_３燃烧催化剂,比较了γ－ＡＩ_２Ｏ_３、α－ＡＩ_２Ｏ_３、堇青石（２ＭｇＯ·２Ａｌ_２Ｏ_３、５ＳｉＯ_２）和ＺｒＯ_2四种载体的负载效果．用ＸＲＤ,ＤＰＲ着重研究了γ－Ａｌ_２Ｏ_３载体上由于负载量不同、焙烧温度不同引起的催化剂物相变化和二甲苯完全氧化的催化活性变化．     

负载型La0.8Sr0.2MnO3燃烧催化剂的载体效应

Combustion catalysts La0.8Sr0.2MnO3 supported on γ-Al2O3, α-Al2O3, cordierite (2MgO•2Al2O3•5SiO2) and ZrO2 were compared. Further investigation was focused on LSM/ γ-Al2O3 catalyst. It was observed that LSM/γ－Al2O3 catalyst loaded with 20% (mass fraction) LSM (La0.8Sr0.2MnO3 or corresponding oxides), heated at 750℃ or above, perovskite-type oxides were found by XRD examination, whereas, the same catalyst loaded with 10% or less LSM, perovskite oxides were absent, calcination temperature about 750℃ is necessary for the formation of perovskite structure in LSM/γ-Al2O3 catalysts. High activity of complete oxidation of xylen will be obtained when perovskite-type oxides.
Investigation of TPR showed that neat LSM or LSM/γ-Al2O3(20%) was reduced by H2-N2 mixed gas. Two degradation processes took place. In the first, reduced temperature peak was about 350 - 450℃. If reduction ended at 400℃, perovskite structure was retained, which may be due to the reduction of Mn3+to Mn2+ on the surface of LSM only. In the second process, perovskite structure was destroied, and La2O3, Mn2O3, Mn - Sr - O oxides could be obtained, which took place in the temperature range 685 - 750℃ and ended at 800℃. This was proved by TPR experiments (Fig. 3, 5) and XRD patterns (Fig. 4)
Catalysts LSM/γ-Al2O3(10% or 20%) heated at 500℃ have only one TPR peak, i. e. lower temperature peak. This is due to the absence of perovskite-type oxides in the catalysts. However, neat LSM or LSM/γ-Al2O3(20%) heated 750℃ or above, not only the first low temperature TPR peak but also the second peak, which is contributed by the perovskite-type oxides in these catalysts appeared. Therefore, the second TPR peak, i. e. the higher temperatue peak is a characteristic peak for perovskite-type oxides in the reduced process. When LSM/ γ-Al2O3 (10%) catalys is heated at 750℃, no perovskite-type oxides were detected by XRD, and the second reduction peak was absent also in TPR process. \
The order of the second reduction peak temperature(characteristic peak of perovskite - type ox- ides) is: neat LSM(750℃）> LSM/γ-Al2O3 20% (685-698℃) -deposited LSM/γ-Al2O3 (698℃) > LSM/γ-Al2O3 15% (677 - 680℃) >(LSM/γ-AL2O3 10% 620 - 630℃, for Mn - Al - O medium oxides on surface). It is correleted with the increasing of the effect of support sequentially.
When LSM/γ-Al2O3 catalysts were heated at 900℃, more stable phase, spinel MnAl2O4 appeared, which could be proved by TPR of model catalyst MnAl2O4/γ-Al2O3.     

基于KFCM增量更新的无线电引信目标识别方法

针对传统无线电引信在复杂电磁环境下作用效果较差的问题,以连续波多普勒引信为例,通过对引信检波输出信号频域的分析,提出一种基于熵的特征提取方法,并利用KFCM算法对信号进行分类识别。由于实际战场环境复杂且不可预测,其背景噪声强度与实验环境下存在差异,因此结合KFCM增量更新特性,使分类模型根据噪声强度变化而实时更新调整,从而达到更好的分类效果。实验结果证明,基于增量更新KFCM算法能显著提高不同信噪比下引信目标识别能力,将KFCM增量更新算法运用到无线电引信抗干扰能取得良好效果。