纤维素-三(4-甲基苯甲酸酯)手性固定相的制备及禾草灵对映异构的拆分

用微晶纤维素和甲基苯甲酰氯反应合成了手性填料纤维素-三(4-甲基苯甲酸酯)(CTMB),并涂敷于氨丙基硅胶上,制备成手性固定相(CSP)。用高效液相色谱法,在正相条件下用此手性固定相,对农药禾草灵外消旋体进行了拆分,考察了流动相组成,醇效应,温度及色谱柱长度对拆分及保留的影响,并对其在该手性柱上保留机理进行了讨论。     

寡糖手性固定相研究进展

介绍了葡萄糖、纤维二塘、棉子糖、乳糖等用来作为高效液相色谱手性固定相的研究进展,研究发现这几种糖类作为高效液相色谱的手性固定相拆分效果比较好,比较有前途.同时展望了高效液相色谱手性固定相的发展前景.     

HPLC法手性拆分百湿芬肠溶胶囊中的酮洛芬

建立了百湿芬肠溶胶囊中酮洛芬的手性拆分方法.利用PM-β-环糊精手性固定相拆分百湿芬肠溶胶囊中的酮洛芬对映异构体,对流动相的组成、pH值、流速等色谱条件进行优化.以甲醇-0.1％乙酸三乙胺=(40:60)做为流动相,缓冲溶液pH=4.00,色谱柱温为25℃,流动相流速为0.7 mL/min,在此条件下,百湿芬肠溶胶囊中的酮洛芬得到较好拆分.     

分子印迹技术的应用研究进展

文章综述了分子印迹技术在药物及对映异构混合物的手性拆分,分子印迹聚合物作为色谱固定相用于分离和对药物以及环境有害物质的检测的研究进展.同时还介绍了分子印迹聚合物作为各种化学传感器的敏感元件,作为酶模拟催化剂的研究的现状.     

奥丁尼酮洛芬缓释胶囊中酮洛芬的手性拆分

采用高效液相色谱法,以β-环糊精为手性固定相拆分奥丁尼酮洛芬缓释胶囊中酮洛芬对映体,并对流动相中甲醇的含量、流动相的pH值、缓冲盐的浓度等色谱条件对拆分结果的影响进行了探讨.结果表明,在柱温为25℃,pH值为4.0,采用0.01 mol/L的磷酸二氢钾缓冲溶液,甲醇40%（V/V）作流动相时,奥丁尼酮洛芬缓释胶囊中的酮洛芬对映体能达到较好分离.     

纤维素型手性固定相制备及手性分离综合实验设计

以微晶纤维素为原料,合成了纤维素-三(1-萘基氨基甲酸酯),再将其涂覆于氨丙基硅胶表面,制备成手性固定相。利用傅里叶变换红外光谱仪、元素分析仪、扫描电镜等方法对纤维素衍生物及固定相进行了表征。将该固定相填充于空的色谱柱中,制备成手性色谱柱,用高效液相色谱检测了所制备色谱柱对几种手性样品的对映体分离性能。本实验涉及有机合成和表征的相关知识,并结合手性药物色谱分析等应用性问题,综合性较强,可作为大学本科综合实验教学内容。     

粉笔层析实验探究

层析技术是近代生物化学实验中常用的分析方法.任何层析过程都是在2个相中进行的.一个是固定于支持物上的固定相,另一个是流经固定相的流动相.由于样品中各组分理化性质(如溶解度、吸附能力、分子形状、分子所带电荷的性质和数量、分子表面的特殊基团、分子量等)不同,表现出对固定相和流动相的亲和力也各不相同.     

环糊精衍生物在毛细管电泳手性药物拆分中的应用

对国内外毛细管电泳在手性物质拆分领域的研究与应用进行了综述,特别对近五年来以各种环糊精衍生物作为手性分子识别试剂拆分手性物质方面做了归纳总结,进一步对以环糊精衍生物作为手性选择试剂在毛细管电泳手性药物拆分中的应用研究做了简单展望.     

高效液相色谱手性固定相的最新研究进展

综述高效液相色谱手性固定相的发展过程,介绍手性冠醚类、Pirkle型、配体交换型、大环抗生素、多糖类、环糊精类、分子印迹类、蛋白质类、手性聚合物类手性固定相在2006～2007年的发展过程,展望高效液相色谱手性固定相的发展前景.     

高效液相色谱法拆分酮咯酸氨丁三醇盐对映体

利用PM-β-环湖精手性固定相高效液相色谱法直接拆分酮咯酸氨丁三醇盐对映体．本试验研究了流动相中甲醇的含量、流动相的pH值、缓冲盐的浓度等色谱条件对拆分结果的影响．结果表明，在柱温为25℃，pH值为4．0，采用0．01mol／L的磷酸二氢钾缓冲溶液（含35％甲醇（V／V））作流动相时，酮咯酸盐对映体能达到基线分离．     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?     

Western and Eastern culture differences in commercial field

The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity.     

只要努力,不要后悔

There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.     

浅谈移民问题

Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.     

风的曲线

Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose.     

团图为数的图中的闭团贯数

Given a graph G,a subgraph C is called a clique of G if C is a complete subgraph of G maximal under inclusion and |C|≥2. A clique-transversal set S of G is a set of vertices of G such that S meets all cliques of G. The clique-transversal number, denoted as TC (G), is the minimum cardinality of a clique-transversal set in G. The clique-graph of G, denoted as K (G), is the graph obtained by taking the cliques of G as vertices, and two vertices are adjacent if and only if the corresponding cliques in G have nonempty intersection. Let F be a class of graphs G such that F={G|K(G) is a tree}. In this paper the graphs in F having independent clique-transversal sets are shown and thus TC (G)/|G|≤1/2 for all G ∈ F.     

Sister Carrie, an Adherent of Desires

Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.