离子色谱法检测甲氧胺盐酸盐合成过程中的两种二磺酸盐

建立测定羟胺二磺酸盐和甲氧胺二磺酸盐的离子色谱法,并将该方法用于甲氧胺盐酸盐的质量控制。使用抑制型电导检测离子色谱,通过考察不同浓度的Na,CO2和NaHCO3流动相体系对分离效果的影响,选择最适宜的流动相为3．0mmol／LNa2CO3＋3．8mmol／LNaHCO3。两种二磺酸盐的检测线分别为0．15和0．20mg、kg,加标回收率分别为97．8％和98．7％;方法重现性较好,RSD（n=5）低于3％,所建方法适用于甲氧胺盐酸盐的磺酸盐质量控制。     

Synthesis of a quaternary amine anion exchange resin and study [of] its adsorption behaviour for chromate oxyanions

Glycidyl methacrylate/N,N'-methylene bis-acrylamide (GMA/MBA) was prepared and allowed to react with tetraethylenepentamine (TEP) to give glycidyl methacrylate amine resin (RPA) followed by treatment with glycidyl trimethylammonium chloride (GTA) to give glycidyl methacrylate resin bearing quaternary ammonium chloride moieties (RQA). Zeta potential measurements showed that RQA particles are positively charged over pH 2-10 indicating the strong basic nature of the quaternary amine sites. The effect of pH on the recovery of chromate by RPA and RQA was examined. The results indicated that RQA is an efficient sorbent for chromate from both acidic and basic media. The repeated use of RQA was tested through stripping the adsorbed chromate using a mixture of 0.05 NaOH and 2 M NaCl in the case of the uptake from acidic media and using 2 M NaCl solution in the case of alkaline solutions.     

离子色谱法和化学法测定NO3-、NO2-、SO42-的实验研究

通过用离子色谱法和化学法测定环境中NO3^-、NO2^-、SO4^2-的对比实验，得出在选定范围内两种方法没有显著性差异的结论。在测定每个样品的多个组份时，离子色谱法更具灵活性、快捷性，两种方法的对比实验研究，为环境监测人员更科学合理地选择监测方法提供依据和参考。     

液体电阻率与温度和浓度之间关系的测量

通过液体温度、浓度与电阻率之间的关系的测定，得出液体导电与一般金属导电之间的区别，掌握液体电阻率的温度特性和浓度特性，掌握导电液体均匀加热方法。     

低能离子束辐照对纤维素微观结构变化的影响

采用红外光谱(IR),X射线衍射分析和扫描电镜(SEM)对低能离子(N+)注入纤维素粉微观结构的变化进行了研究。结果表明,低能离子辐照使纤维素分子内和分子间氢键均发生了断裂;随着辐照剂量的增加,纤维素相对结晶度逐渐减小,当注量增加到1500×1014cm-2时,相对结晶度较对照减少6.84%;纤维素颗粒直径逐渐变小,纤维变得越来越不完整,纤维表面出现较明显分层脱落现象,大多呈现的是细小碎片。     

离子束辐照脱氧核糖核酸(DNA)及其碱基的ESR研究

用电子自旋共振波谱法对氮离子束辐照脱氧核糖核酸和碱基产生的自由基进行了研究。结果表明,离子束辐照DNA和碱基产生的自由基为离子自由基;自由基产额随辐照剂量的增加而上升,最终趋于饱和。在室温(10-20℃)和干燥条件下,对产生的自由基进行了一个多月的观测,不见有大幅度衰减,表明在室温条件下辐照产生的自由基具有较长的寿命。     

离子源灯丝绝缘子的优化设计

通过对离子注入机离子源灯丝绝缘子的结构、尺寸、实际工作效果等方面的分析,提出了一种注入机离子源灯丝绝缘子的优化设计.该方案减少了离子源因绝缘效果不良引起的系统工作不稳定故障,灯丝使用寿命延长至50 h以上.     

水库优化调度中的异轨同效问题

针对确定性水库优化调度问题,引入近似最短路径方法,寻求优化调度的近似最优解,从而证实"异轨同效"现象存在的可能性。借鉴流域水文模型的"异参同效"研究成果,视隐随机调度问题中的调度规则参数为具有概率分布特征的参数,视调度目标函数为似然函数,采用贝叶斯方法估计最优调度轨迹的区间分布,开展水库调度的最优调度轨迹的等效性研究。实例分析结果表明:进行水库优化调度的"异轨同效"研究,可以估计最优调度轨迹区间,从而将传统调度的单点决策转变为区间决策,更符合调度操作实际情况。     

Anti-corrosion characteristics of nitride-coated AISI 316L stainless steel coronary stents

The corrosion resistance of TiN and TaN coatings deposited on AISI 316L stainless steel thread-coiled coronary stents by pulsed bias arc ion plating is evaluated by electrochemical methods in deaerated Tyrode's simulated body fluids (37 ± 1 °C). The free corrosion potential of the TaN-coated stents is found to be nobler than that of the TiN-coated and uncoated stents throughout most of the immersion time. The potentiodynamic polarization test results indicate that the TaN coatings offer better passivation stability and anti-breakdown performance. The longer-term 6-month immersion tests disclose slight localized corrosion on the surface of both coatings, but no film delamination or large area pitting can be observed indicating reasonably good corrosion resistance after the long period.