WATER-BLOWN POLYURETHANE RIGID FOAMS MODIFIED BY CHEMICAL PLASTICATION

1. INTRODUCTIONThese years, HCFC-141b may be the most used blowing agent for its useful properties. But, because of its high global warming effect leading to the destruction of the ozone layer, production of HCFC141b has been forbidden. However, there are…     

O-烷基-O-(2′-甲酰缩氨基硫脲苯基)-N-烷基硫代磷酰胺的合成(一)

本文报道了O-烷基-O-(2′-甲酰缩氨基硫脲苯基)-N-烷基硫代磷酰胺类化合物的合成方法,化合物3c和3e具有良好的除草活性。     

有机分子与聚电解质静电吸附成膜特性研究

选取多种有机分子及聚电解质，采用静电吸附自组装法制备了聚电解质，聚电解质、聚电解质，有机分子、有机分子，有机分子的复合薄膜，讨论了这些体系的静电吸附成膜特性及其成膜机理．     

ELECTRON PARAMAGNETIC RESONANCE STUDIES OF SINGLE CRYSTAL SODIUM HEXAMOLYBDOCHROMATE (Ⅲ)Cr~(3+)/Na_3(AlMo_6O_(24)H_6)·8H_2O

An X-band EPR study on a Na_3(CrMo_6O_(24)H_6)·8H_2O single crystal diluted by its isomor-phic compound Na_3(AlMo_6O_(24)H_6)·8H_2O at room temperature is reported. Using the least squares-fitting method to simulate the EPR data for principal planes, the Hamiltonian parameterswere obtained. The principal values of the g tensors are g_(ZZ) = 1.904, g_(XX)= 1.973, g_(YY)=1.933. The zero field splitting tensor parameters are D = 0.275 cm~(-1), E = 0.05 cm~(-1). The fielddependence of Cr~(3+) energy levels with field at different angles from the principal axes whenthe field is along the principal planes is calculated based on these experimental parameters.The isofrequency plots of calculated field vs. angle are also shown. They agree well with theexperimental results.     

两种计算吸光光度法同时测定钙镁

研究了在pH10．5的硼砂-氢氧化钾缓冲溶液和乙醇的增敏作用条件下，偶氮氯膦Ⅰ与钙、镁的吸收特性，建立了多波长光度法同时测定钙和镁的方法。采用两种矩阵算法对试验数据进行处理，并对结果进行比较和分析。钙和镁含量在0～25μg／25ml范围内用计算法Ⅱ能得到准确结果。     

Analysis of light propagation characteristic in the aero-optic flow field of cone-headed vehicle with side window

Aero-optic imaging deviation research is carried out for infrared-guided vehicle with cone-head side window, with a focus on the propagation characteristics of light in an aero-optic flow field. When the light entering the aero-optic flow field from the free-stream should be close to the normal, numerous data indicate that the light is refracted away from the normal. This paper divides the aero-optic flow field into two parts and uses the gas density distribution in the aero-optic flow field to ...     

扭曲的涡旋光束在海洋湍流中的传输因子

基于扩展惠更斯-菲涅尔原理和维格纳分布函数(Wigner distribution function,WDF)二阶矩,推导了部分相干扭曲涡旋光束(partially coherent twisted vortex beam,PCTVB)在海洋湍流中传输时的M2因子和角扩展θ(z)。通过数值模拟方法详细研究了海洋湍流对光束M2因子和角扩展θ(z)的影响,结果表明温度方差耗散率ΧT和温度盐度贡献比w越大、动能耗散率ε和各向异性因子ξ越小时对PCTVB的M2因子和角扩展θ(z)的影响越大。此外研究发现,相较于非扭曲涡旋光束(PCVB),PCTVB有更好的抗海洋湍流的能力,且增大拓扑荷数m以及扭曲因子绝对值｜μ｜后,PCTVB的M2因子和角扩展θ(z)显著减小,光束的抗海洋湍流能力增强。并且增大束腰宽度w0和波长λ,以及减小初始相干长度δηη(η=x,y)同样可以增加光束抗海洋湍流的能力。本文的数值研究结果对海洋光通信具有重要意义。     

一种新型单层递归神经网络解决非光滑伪凸优化问题

非光滑伪凸优化问题是一类比较特殊的非凸优化问题,常出现在各类科学与工程应用中,因此具有很大的研究价值.针对现有神经网络模型解决非光滑伪凸优化问题存在的不足,该文基于微分包含理论,提出一种新型单层递归神经网络模型.通过理论分析,证明了神经网络状态解在有限时间内收敛到可行域,且永驻其中,最终神经网络状态解收敛于原优化问题的最优解.最后,通过数值实验,验证了所提理论的有效性.与现有的神经网络相比,该文所提神经网络模型结构简单仅为单层,不需要提前计算罚参数,且对初始点选取没有任何特殊的要求.     

脱色阴离子交换剂的再生研究

提出一种新的离子交换剂再生理论，即吸附物的脱附依靠离子交换和络合的协同效应完成．以二价钙离子为再生剂，对糖液脱色用的阴离子交换树脂和阴离子交换纤维进行再生，并与传统的碱性钠盐相比较，研究证明钙离子为再生剂的工艺，具有低成本、无污染的特点．