中和渗析法中部分氨基酸的传质过程研究(英文)

对甘氨酸、丙氨酸和丝氨酸在中和渗析法中的传质行为进行了研究,渗析结果表明,它们在等电点处的传质速率最大,对这种现象,可通过定量比较不同的pH条件下甘氨酸在离子交换膜上的浓度来予以解释,取决于溶液pH值的甘氨酸传质速度与所计算出的在不同pH条件下与阴、阳离子交换膜交换的甘氨酸浓度相一致。     

硅胶载体酸催化下富马酸二苄酯的合成

以顺酐和苄醇为原料，采用硅胶载体酸为催化剂，合成了富马酸二苄酯．讨论了载体酸催化剂的用量、原料配比及投料方式、反应温度及反应时间对产物收率的影响     

The glycinergic inhibitory synapse

Glycine is one of the most important inhibitory neurotransmitters in the spinal cord and the brainstem, and glycinergic synapses have a well-established role in the regulation of locomotor behavior. Research over the last 15 years has yielded new insights on glycine neurotransmission. Glycinergic synapses are now known not to be restricted to the spinal cord and the brainstem. Presynaptic machinery for glycine release and uptake, the structure and function of postsynaptic receptors and the factors (both pre- and postsynaptic) which control the strength of glycinergic inhibition have been extensively studied. It is now established that glycinergic synapses can be excitatory in the immature brain and that some inhibitory synapses can corelease γ-aminobutyric acid (GABA) and glycine. Moreover, the presence of glycine transporters on glial cells and the capacity of these cells to release glycine suggest that glycine may also act as a neuromodulator. Extensive molecular studies have revealed the presence of distinct subtypes of postsynaptic glycine receptors with different functional properties. Mechanisms of glycine receptors aggregation at postsynaptic sites during development are better understood and functional implications of variation in receptor number between postsynaptic sites are partly elucidated. Mutations of glycine receptor subunits have been shown to underly some human locomotor disorders, including the startle disease. Clearly, recent work on glycine receptor channels and the synapses at which they mediate inhibitory signalling in both young and adult animals necessitates an update of our vision of glycinergic inhibitory transmission. Received 8 September 2000; received after revision 1 December 2000; accepted 21 December 2000     

两种贵金属萃取剂萃取性能的研究

以N ,N二苄基甘氨酸和N ,N二苯基甘氨酸为固定相 ,以不同浓度的盐酸和高氯酸为展开剂 ,研究了它们对 8种贵金属的萃取行为 .实验表明 :N ,N二苯基甘氨酸的萃取能力较N ,N二苄基甘氨酸大 ;两种萃取剂在盐酸体系中的萃取能力比在高氯酸体系中大 .     

钴（Ⅲ）配合物取代反应的动力学研究

用分光光度法研究了在ｐＨ为８．５７的３０％（ｖ／ｖ）乙醇溶液中，甘氨酸与二羟基二邻菲罗琳钴（Ⅲ）配合物取代反应的动力学。提出其反应机理为交换高解机理，根据静态平衡，推导其反应速度公式，并求得其反应的△Ｈ￣＋＝８２．８３ｋＪ·ｍｏｌ￣（－１），△Ｓ￣＋＝７９．４２Ｊ·ｍｏｌ￣（－１）·Ｋ￣（－１）。     

甘氨酸对内毒素部分生物学效应的拮抗作用

在发现甘氨酸是有可能成为内毒素拮抗剂的重要药物之一的基础上,从二个方面进一步观察了Ｇｌ６拮抗ＥＴ的效应。     

离子膜法分离氨基乙酸的研究

设计探讨了离子膜法分离氨基乙酸新工艺,该分离新工艺不存在甲醇污染,使用洁净能源———电力,降低能耗５０％。新工艺操作方便,成本低,三废少,具有工业化前景。     

胡椒醛甘氨酸席夫碱的合成,表征及抑菌活性

合成了胡椒醛甘氨酸钾席夫碱，并用元素分析、红外光谱、电子光谱和氢核磁共振谱对其进行了表征．摩尔电导数据表明，合成化合物为１１型电解质．抑菌试验结果表明，该席夫碱具有抑制铜绿假单胞菌、大肠埃希氏杆菌和金黄色葡萄球菌生长的活性     

HPLC法监测DL-丝氨酸的合成研究

采用HPLC方法，以OPA为柱前衍生化试剂，对常压下甘氨酸铜法合成DL-丝氨酸的过程进行了监控，通过改变加料方式及调节pH值，提高了丝氨酸的含量，得出了常压下丝氨酸的最佳合成条件为：n_铜离子∶n_甘氨酸∶n_甲醛=1∶278∶973，pH =8.5～9.5 ,反应时间1.5h，丝氨酸最高质量浓度为18.86 g/L。