绕圆柱体自由表面磁流体流动和传热的研究

本文对在不同雷诺数下,绕圆柱体的磁流体自由表面流动及传热进行了模拟,分析了磁场对绕流圆柱尾迹和涡分离的影响,获得了两种雷诺数下的电磁力密度、流场和温度场分布。结果表明,磁场不仅影响了流动的形态,而且对湍流有抑制作用,降低了自由表面的更新机制,从而减少了传热能力;在相同的Hartmann数下,相比低雷诺数下的流动换热情况,高雷诺数下的湍流不能被完全抑制,自由表面与尾迹的相互作用也较强,因而自由表面换热也较强。     

Optosensing of hydrochloric acid based on the fluorescence quenching of a flavone copolymer

An optical fiber sensor for the continuous determination of hydrochloric acid is presented. It is based on the fluorescence quenching of a flavone containing copolymer membrane by hydrochloric acid. The quenching efficiency is greatly enhanced in the presence of Fe(III). This enhancement is attributed to the primary inner filter effect, as well as the formation of a complex between the 4′-N,N-dimethylaminoflavone group in the copolymer and the Fe(III) species extracted from hydrochloric acid solution. The optical response is linear and reversible for 0.10–6.00 mol L^–1 HCl with a response time of the order of a second. The standard deviations for repeated alternative measurements of 0.20 and 2.00 mol L^–1 hydrochloric acid are 0.32% and 0.46% (n = 10), respectively, indicating a good reproducibility. Because of the covalently bonding of the dye to polymer, the sensor exhibits also a good stability. Selectivity has also been evaluated for some potential interferents. The sensor in conjunction with a flow-injection system can be used for on-line determination of hydrochloric acid.     

Ti－Si沸石的催化氧化性能Ⅱ．环己醇的氧化及环己酮的肟化

Ｔｉ－Ｓｉ沸石的催化氧化性能Ⅱ．环己醇的氧化及环己酮的肟化夏清华，王公慰，应慕良，郑禄彬（中国科学院大连化学物理研究所，大连１１６０１２）关键词Ｔｉ－Ｓｉ沸石催化剂，Ｈ_２Ｏ_２氧化剂，环己醇氧化，环己酮肟化．１．前言环己酮肟是生产ε－己内酰胺的关键中...     

ARL—3520AES电感耦合等离子体发射光谱仪疑难故障的分析与排除

介绍了在瑞士ＡＲＬ公司生产的ＩＣＰ－３５２０ＡＥＳ型电感耦合等离子体原子发射光谱仪上存在的一种疑难故障的分析与排除过程，对同类型仪器的故障分析有借鉴作用。     

新显色剂对羧基苯基重氮氨基偶氮苯的合成及与镉显色反应的研究

本文报道了新色剂对羟基苯基重氮氨基偶氮苯的合成。     

Ar—Kr溶液扩散系数的分子动力学模拟及其与温度的关系

用分子动力学模拟方法研究确定Ａｒ－Ｋｒ溶液的自扩散系数Ｄ１、Ｄ２和互扩散系数Ｄ１２以及它们随温度变化的规律。结果表明，分别用Ｇｒｅｅｎ－Ｋｕｂｏ法和Ｅｉｎｓｔｅｉｎ法得到的扩散系数在数值上一致；该溶液的３种扩散系数均满足Ｄ＝Ｄ０ｅ＾Ｅ／ＲＴ关系。     

网间交联型增韧环氧树脂/蓖麻油聚氨酯互穿网络聚合物的动态力学性能和形态结构

以增韧环氧树脂(TEP)和蓖麻油聚氨酯[PU(CO)]形成的互穿网络聚合物(IPN),两网络间具有一定数量的交联点,在一定组成下,该IPN的tanδ-T曲线半峰宽达100℃,tanδ最大值接近1,阻尼性能良好。形态研究表明,该IPN既有增韧环氧树脂本身的两相结构,又有IPN的两相结构。