铈离子引发壳聚糖与MMA接枝共聚的研究

在乙酸水溶液中，以铈盐为氧化还原引发剂，在氮气存在下，壳聚糖与ＭＭＡ可发生接枝共聚反应。接枝百分比及均聚物百分含量依赖于反应温度、时间和引发剂的浓度，但不依赖于单体的浓度。表观活化能为７４．４ｋＪ／ｍｏｌ。接枝物不溶于壳聚糖的溶剂，在丙酮中发生溶胀现象。     

液相对流对固液界面稳定性的影响

以模型合金丁二腈－乙醇的强制性晶体生长为基础，利用自行研制的液相对流驱动装置，详细考查了液相自然对流及强迫对流作用下，模型合金平界面失稳的动态生长过程，证实了液相的流动加快了液相温度与浓度分布的均匀化，从而增强了液／固界面的稳定性。并且随流动速度的增加，界面稳定性提高。     

Intermodulation analysis of the collector-up InGaAs/InAlAs/InP HBTusing Volterra series

The intermodulation (IM) distortion of the collector-up InGaAs/InAlAs/InP heterojunction bipolar transistor (HBT) is analyzed using Volterra-series theory. A T-equivalent circuit is used for this analysis. The contribution and interaction of four nonlinear elements: base-emitter resistance, base-emitter capacitance, base-collector capacitance, and common base-current gain are analyzed. For the particular device under investigation, it is found that the cancellation effect is not significant and the base-emitter resistance nonlinearity dominates the third-order IM     

注水站微机数据采集与控制系统

用工控机组成了油田注水站数据采集系统．给出了系统的组成及测量方法，并讨论了系统的可靠性等问题．     

卫星包装箱的随机隔振优化分析

用钢丝绳隔振器将卫星包装箱支承在运输车上,将卫星与车辆简化为二自由度体系,优化分析了在随机路面上行驶时使包装箱响应最小之隔振参数,对实测得到的钢丝绳减振器的非线性迟滞性能作了描述,提出了统计线性化分析的方法。     

热塑性聚氨酯增韧改性聚甲醛的研究

本文对ＰＯＭ／ＴＰＰＵ／Ｚ－３共混体系进行了研究，结果表明，增容剂Ｚ－３可控制共混体系中分散相的颗粒尺寸及分布，起着聚集剂的作用。随着ＴＰＰＵ用量的增加，共混合金的结晶度和拉伸强度增降低，缺口冲击强度出现峰值，ＭＩ下降，当ＰＯＭ／ＴＰＰＵ／Ｚ－３＝１００／７／０．４９时，共混合金的缺口冲击强度达到最大值。     

50kg／m钢轨轨底缺陷的检验和分析

钢轨轨底缺陷有三种：底伤、结疤和底裂缺陷。取２０根有底缺陷５０ｋｇ／ｍＵ７１Ｍｎ钢轨做试样，通过低倍、断口、金相检验和扫描电能谱分析，详细描述了轨底缺陷的宏观和微观特征，研究出钢轨轨底缺陷出现的规律臁其产生的原因。通过对比试验，发现淄博１号保护渣有利于改善钢锭表面质量，提高钢轨一级品率。     

Novel polymeric aromatic lithium sulfonylimides as salts for polymer electrolytes

Three new polymeric aromatic lithium sulfonylimides were used as salts in high molecular weight poly(ethylene oxide) (PEO) electrolytes. Their conductivity and electrochemical stability behaviors were investigated. The electrolytes with lithium poly[4,4′‐(hexafluoroisopropylidene)diphenoxy]sulfonylimide (LiPHFIPSI) showed a better conductive performance compared with the other two lithium salts. The best conductivity was obtained for PEO/LiPHFIPSI EO/Li = 16 (1.90 × 10^?4 S/cm at 60°C). Thermal analysis indicated that the salts effectively decreased the crystallinity of PEO. Moreover, the electrolytes also had good electrochemical stability and their oxidative potential was to 5.5 V versus Li/Li⁺. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1802–1805, 2002     

Stabilization of SnO2 ultrafine particles by additives

In order to stabilize ultrafine particles of SnO₂ which is essential to obtain high gas sensitivity, a systematic investigation was undertaken regarding the stabilizing effects of 5 at% impregnated foreign additives, consisting of oxides or polyoxy compounds of 31 metals and 3 non-metals. The data of specific surface area, SA, as well as SnO₂ crystallite size, D, evaluated from X-ray diffraction showed that the additives could be classified into several groups according to the effectiveness. The most effective group, consisting of P-Ba, Sm, Ba, P, Mo, W, Ca, Sr, Cr and In, could keepD less than 10 nm even after calcination at 900°C, whereas pure SnO₂ underwent grain growth to haveD of 13 and 27 nm at 600 and 900°C, respectively. Electron microscopy revealed that neck sizes, X, between crystallites were fairly proportional toD(X/D = 0.80). A simple analysis of SA and D data based on a monosized sphere model suggested that each crystallite was coordinated with 3–4.5 neighbours through the necks. The existing state and stabilizing mechanism of additives are discussed in conjunction with the electrical resistance of porously sintered elements.