High molecular weight (C35 +) n-alkanes of Neogene heavily biodegraded oil in the Qianmiqiao region, North China

With wax content of 1.62%, heavy oil has been produced from the sandstone reservoirs of Neogene Guantao Formation (Ng1^Ⅲ). In the GC and GC-MS RIC profiles of its aliphatic fraction, n-alkanes are totally lost, which shows the result of heavy biodegradedation. However, the remaining trace C₁₃－C₃₆ n-alkanes can be still seen from its m/z 85 mass chromatogram. In addition, a complete series of C₃₅－C₇₃ high molecular weight (HMW) n-alkanes was detected by high-temperature gas chromatography (HTGC). The HMW n-alkane series shows a normal distribution pattern, a major peak at nC₄₃, obvious odd-carbon-number predominance, CP_I37—55 and OEP_45—49 values up to 1.17 and 1.16—1.20 respectively. The present study not only has conformed the strong resistibility of HMW n-alkanes to biodegradation in crude oils as concluded by previous researchers, but also has provided some significant information on source input and maturity for the heavily biodegraded oil in the Qianmiqiao region.     

Chiral separation of racemic drugs using molecular imprinting

Molecularly imprinted polymers (MIPs) of (S)-ketoprofen and (S)-naproxen are prepared using non-covalent imprinting in the presence of template molecules. The prepared MIPs are used as the chiral stationary phase to separate ramemic naproxen and ketoprofen. The results show that racemic naproxen and ketoprofen are efficiently resolved on MIPs. The effect of concentration of acetic acid in the mobile phase is studied, and the data are analyzed using the affinity chromatography model, and the close agreement is achieved between the simulated and experimental curves. The results suggest that the affinity chromatography mechanism controls the retention in this system. Moreover, the affinity chromatography equilibrium constants on (S)-naproxen and (S)-ketoprofen are estimated.     

红外激光光声光谱检测范围扩展的研究

本文对红外激光光声光谱检测范围扩展进行了研究。测试系统采用了 DNP 色谱柱,设计了可通过试样气流的可加热亥姆霍兹共振光声池,采用了两只光声池串联差分与锁相放大的办法以减小本底噪声。实验对含有乙酸乙酯和乙酸丁酯有机化合物的试样进行了分析,获得了光声色谱图。实验结果表明,当光声池前连色谱柱,即可检测含重分子量有机化合物的混合物,扩大了激光光声光谱的检测范围。     

三氟乙酰氨基酸正丁酯的色谱分离与研究

本文对氨基酸的酯化和酰化条件进行了优选,建立了三氟乙酰正丁酯的气相色谱分离方法;采用毛细管操作系统,提高了氨基酸衍生物的分离度,缩短了分析时间,提高了定量分析的准确度。经食品样品测定,均获得满意的结果。     

气相色谱法快速测定啤酒中的酒精含量

本文介绍了一种快速、准确测定啤酒中酒精含量的气相色谱法。本法使用氢焰离子化检测器，ＧＤＸ－１０３（６０～８０目）为固定相，以异丙醇为内标物。样品脱气后不经任何处理即可直接进样，大大缩短了分析周期。该法可用于啤酒的质量控制。     

一种定性分离L──脯氨酸和L──羟脯氨酸展开剂的选择

为了准确地定性Ｌ－脯氨酸，排除Ｌ－羟脯氨酸的干扰，通过实验确定了正丁醇：乙酸：水＝２：２．４的混合溶剂系统，得到了满意的结果。这对于Ｌ－脯氨酸提取后的定性检验是很方便的。它同时也适用于Ｌ－羟脯氨酸的定性。     

免疫丙种球蛋白的缔合与分离及其动态性质

用凝胶渗透色谱法研究了聚乙烯基吡咯烷酮(PVP)、血清白蛋白和医用明胶等稳定剂对免疫丙种球蛋白(IgG)的作用和效果,结合准弹性激光光散射法研究了它们对IgG分子平移扩散系数和流体力学尺寸的影响。结果表明,PVP和血清白蛋白对IgG单体起着屏蔽稳定作用而防止其自身凝聚,但并不与IgG形成复合物,因而不会改变IgG单体的分子结构与构型。     

薄层扫描法测定抗菌优中各组分含量的研究

本文提出了抗菌优(复方磺胺甲噁唑)中磺胺甲基异噁唑(SMZ)和甲氧苄胺嘧啶(TMP)两组分薄层色谱扫描同时测定的新方法。本法利用以水饱和的乙酸乙酯与氧仿(2+1)混合溶液为展开剂,在硅胶GF_(254)板上将SMZ和TMP两组分分离后,直接进行薄层色谱扫描,测定其含量。本法操作简便、快速、灵敏度高,重现性好。