Evaluation of micellar liquid chromatography and capillary zone electrophoresis for dope control in sport

Micellar liquid chromatography (MLC) and capillary zone electrophoresis (CZE) have been evaluated for the analysis of twelve banned drugs in sport including diuretics and -blockers. In MLC, a sodium dodecylsulphate aqueous solution has been used as mobile phase using an octadecylsilica column. In CZE, a pH 8 buffer solution and a silica capillary have been employed. Parameters of retention and efficiency have been compared. Limits of detection with UV detection at 254 nm and relative standard deviations for atenolol, furosemide, nadolol, spironolactone and triamterene were established and compared in both techniques. Examples of direct urine injection into the separation systems are presented. Drugs overlapping in MLC are well resolved in CZE, while the opposite is true for a limited number of drugs. Some interferences from urine may arise in CZE. The selectivity of analysis would be greatly enhanced by using both techniques, which require only filtration as pre-treatment.     

GC-MS监测生活饮用水输配水管材及防护材料中溶出的挥发性有机物

我国的生活饮用水行业中,目前常使用的管材分为金属类管材和非金属类管材两种。由于金属类管材本身的化学特性,行业内必须在此类管材的内壁上进行防腐处理,通常采用一些高分子防腐涂料。可用于给水行业的涂料品种繁多,涂料质量好坏直接影响到水质。我们针对一些常用产品作了浸泡试验,用吹扫捕集-GC-MS方法对水中溶出的可挥发性有机物进行了检测,发现一些产品在水中溶出了大量的甲苯、乙苯、二甲苯、甲乙苯等苯系物,且浸泡30d后仍有溶出物。这些物质长期存在会导致人体中枢神经系统紊乱,严重危害人体健康。行业内关于水源水中此类有机物污染的监测比较充分,而对于防护涂料可能污染水质的状况并未引起足够重视。     

La1-xNdxSrCoO4催化剂的合成及其催化性能

采用聚丙烯胺溶胶-凝胶法制备了类钙钛矿La1-xNDxSrCoO4(x=0.1～0.9)复合氧化物催化剂,考察了其对CO和C3H8的催化氧化活性,并运用XRD、IR和TPR等手段对催化剂进行了表征.结果表明,所制备的样品均具有K2NiF4型结构,适量Nd2O3的加入增加了LaSrCoO4的催化活性,使LaSrCoO4催化剂粒度变小、晶格畸变率变大及与氧的结合能力减弱,从而有利于CO和C3H8氧化活性的提高.     

硼轻掺杂对非晶硅薄膜光电性能的影响

用化学气相沉积法制备了厚度为 2 μm左右、掺杂比为 ( 2～ 6)× 1 0 -6的硼轻掺杂非晶硅半导体薄膜 ,测量了样品光电流随掺杂比、电压和光波长的变化。结果表明 ,非晶硅薄膜的光电流随掺杂比、电场强度和光功率密度的增大而增大 ,光电流灵敏度最高频谱范围随掺杂比和电场强度的增大而增大 ,掺杂比改变对光电流的影响比电场强度和光功率密度变化的影响更明显     

一种亚微米垂直硅墙的刻蚀方法

亚微米垂直硅墙的制备是垂直硅薄膜耦合约瑟夫逊结的关键工艺.本文作者在普通光刻设备基础上,开发了一种在〈100〉硅片上制备亚微米硅墙的刻蚀方法:首先用普通光刻手段刻出较宽的墙区;其次,对非墙区进行迭加注入掺杂;第三,杂质高温横向扩散,第四,掺杂选择性刻蚀;第五,高温氧化减薄.实验结果表明,这种方法可以获得墙宽为0.29μm,墙高为1μm左右的硅墙,而且还有一定的改进潜力.     

掺杂聚苯乙烯制备研究

讨论了惯性约束聚变研究中采用化学及物理手段在聚苯乙烯（PS）材料掺杂卤素、硅、氘等非金属元素以及铁、铬、钛等金属元素的原理和方法。利用硅烷偶联剂对氧化物表面进行了预处理,采用本体聚合的方式将氧化物掺杂在PS网络之中,简述了它们在ICF中的应用。     

Rheological Behavior of Dope Solutions of Poly(acrylonitrile‐co‐itaconic acid) in N,N‐dimethylformamide: Effect of Polymer Molar Mass

The rheological behavior of dope solutions of poly(acrylonitrile‐co‐itaconic acid) or poly(AN‐co‐IA) is important from the point of view of deriving the spinning conditions for good quality special acrylic fibers. The viscosity of the resin dope is dictated by the polymer concentration, molar mass, temperature and shear force. The dynamic shear rheology of concentrated poly(AN‐co‐IA) polymer dope solutions in N, N‐dimethylformamide, in the molar mass (M¯_v) range of 1×10⁵ to 1×10⁶ g/mol, was investigated in the shear rate (γ′) range of 1×10¹ to 5×10⁴ min^?1. An empirical relation between η and M¯_v was found to exist at constant shear rate. The dope viscosity was dependent on the molar mass and the shear rate at a given temperature (T) and concentration. The polymer molar mass index of dope viscosity (m) was calculated as functions of concentration (c), shear rate and temperature. The m values increased with shear rate and temperature. A master equation relating m, with shear rate and temperature was derived for a given dope concentration. At higher shear rates, m tends to the value of 3.4, which is close to the molar mass index of viscosity reported for molten thermoplastics. m increased significantly with shear rate and nominally with temperature, while an increase in concentration decreased it. The onset of shear thinning of the dope shifted to a lower shear rate regime with an increase in polymer concentration and the molar mass. For a given value of molar mass, the increase in viscosity of the dope solution with polymer concentration was dependent on the shear rate.     

硅基稀土热扩散法初探

稀土元素在我国有丰富的贮量．近年来,稀土元素在各种新科技领域中得到不断的开发和利用．各类稀土功能材料在发光和光通信领域中正展现巨大的应用潜力［１］．稀土磁光薄膜材料是优良的记录介质;稀土Ｅｒ由于其特殊的电子结构,已用来制造掺铒光纤激光器和光纤放大器［２］;掺铒硅还可制造发光谱线单一的发光器件［３］,这为实现人们所期待的硅基光电集成提供了有益途径．此外,基于对掺铒硅荧光发射衰减时间的分析,可用于制造温度传感器［４］．因此,稀土在共价半导体材料如Ｓｉ、ＧａＡｓ中的行为研究日益受到重视．但这些工作主要…     

聚氧化乙烯介质中的掺杂硫化锌纳米晶的制备及光学性质

简述了聚氧化乙烯介质中的铽、铕、铥、钆、钇、镓、锰掺杂的硫化锌纳米晶的制备方法以及紫外吸收光谱、激发光谱和光激发发射光谱.制成的硫化锌纳米晶直径为3.0～3.5nm.     

双包层EYDFA增益钳制效果的理论研究

基于速率方程的离散算法,实现了环形腔控制方案下,双包层EYDFA增益钳制的分析,研究了单、多信道情况下增益、噪声指数钳制的效果。结果表明：对于单信道EYDFA,随着衰减器衰减系数的增大,EYDFA的增益钳制范围增大,但信号增益钳制的幅度减小,且信号噪声指数增大;对于多信道EYDFA,只要激光谐振不被破坏,各信道增益都能得到有效钳制。