共查询到20条相似文献，搜索用时 421 毫秒
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目的：对淫羊藿药材中淫羊藿苷的提取工艺进行优化研究.方法：以淫羊藿苷的含量为质控指标,通过单因素考察确定主要因素和水平,然后通过均匀设计实验法对淫羊藿微波提取工艺中的微波功率、提取时间和溶剂倍数等因素进行研究,考察淫羊藿苷的提取工艺.结果：以8倍量的80%乙醇为提取溶剂,超声功率为400W,提取时间为20min,可使药材中淫羊藿苷最大程度的浸出.结论：优选出的微波最佳提取工艺,提取率高,用于工业化生产前景广阔. 相似文献
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在淫羊藿常压提取淫羊藿总黄酮过程中,利用高效液相色谱法对分离提取的淫羊藿总黄酮含量进行了测定.根据液相色谱图可知,乙酸乙酯萃取所得产品杂峰少,产品纯. 相似文献
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微波法提取淫羊藿苷最佳工艺条件确定 总被引：1，自引：0，他引：1
文中采用微波提取法对淫羊藿苷提取工艺条件进行了优化.实验表明,采取微波提取法能够有效地提高目标产物收率.在溶媒用量、辐射时间、辐射功率和提取次数四个主要影响因素中,辐射功率是控制淫羊藿微波辅助提取工艺的关键因素,而微波辐射时间影响最小.微波法提取淫羊藿苷最佳工艺条件为：400m l水,2次提取,500W微波辐射每次10分钟. 相似文献
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高压法提取淫羊藿苷最佳工艺确定 总被引：1，自引：0，他引：1
针对传统提取方法的局限性,在不改变其流程条件下,采用高压提出法对淫羊藿苷提取工艺条件进行了优化．实验表明,采取高压法（5－7MPa）提取淫羊藿苷是一种可行的方法,能够有效地提高目标产物收率．在提取时间、提取次数、固液比和压力四个主要影响因素中,压力因素对本方法提取淫羊藿苷的影响最大,其次是提取次数和时间,而固液比因素对实验的影响较小．高压法提取淫羊藿苷最佳工艺条件为：提取时间10分钟,提取次数2次,固液比1：20．反应温度105℃,反应压力5MPa． 相似文献
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文中综述了淫羊藿中黄酮类化合物分离及鉴定方法的研究进展,为淫羊藿有效成分的开发提供依据.采用水提法提取后,在黄酮类化合物的多种分离方法之中,溶剂萃取法具有价廉、易得等特点.而采用与碱的显色反应来鉴定淫羊藿有效成分黄酮的存在最为简单、方便. 相似文献
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淫羊藿总黄酮常压提取分离工艺研究 总被引：3，自引：0，他引：3
通过水煮提取及萃取方法提取出淫羊藿总黄酮,常压下利用聚酰胺、硅胶等进行柱层析分离提纯淫羊藿总黄酮．最佳工艺为800ml水回流两次。每次两小时,而后,用100ml 95％乙醇回流两小时． 相似文献
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朝鲜淫羊藿林下仿生栽培技术 总被引：2，自引：0，他引：2
朝鲜淫羊藿(Epimedium koreanumNakai.),为小檗科多年生草本植物,又名淫羊藿,俗称三枝九叶草,羊藿叶以干燥地上茎叶入药,是我国传统的补益中药材,被收载于2000年版《中华人民共和国药典》[1],是药典收载的五种淫羊藿药材中质量最好的一种[2].朝鲜淫羊藿为长白山区主产道地药材, 相似文献
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目的:采用大孔吸附树脂法分离纯化巫山淫羊藿中的总黄酮。方法:以淫羊藿总黄酮的含量与收率为考察指标从13种大孔吸附树脂中筛选出了HPD-100树脂为最佳材料,树脂与药材比为2:1,高径比为10:1,淫羊藿的水煎醇沉后的浓度为1 g/L,盐酸-镁粉显色反应与Mon lish显色反应来判断吸附与解吸的始点与终点,洗脱液分别为水与20%乙醇,洗液体积分别为上样药液体积的2.5倍和3倍;解吸附剂为50%乙醇,体积为上柱药液的1.25倍量,吸附与洗脱的流速均为树脂柱床体积的3倍。结果:淫羊藿总黄酮的收率为90%,纯度为60%。结论:用HPD-100树脂分离纯化巫山淫羊藿中的总黄酮是可行的。 相似文献
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《绵阳师范学院学报》2016,(8):74-78
采用Li-6400光合作用测定系统测定巫山淫羊藿叶片光合生理日变化,并用SPSS19.0相关性分析探讨了巫山淫羊藿光合生理特征参数及其环境影响因子的相互关系,为巫山淫羊藿资源的种植栽培提供理论参考依据.结果显示:巫山淫羊藿叶片的最大净光合速率为5.28μmol CO_2·m(-2)·s(-2)·s(-1);其净光合速率、气孔导度和蒸腾速率的日变化均呈双峰曲线,影响净光合速率的主要环境因子是相对空气湿度.水分利用效率日变化与净光合速率显著正相关,与胞间CO_2浓度负相关. 相似文献
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栽培的朝鲜淫羊藿有效成分积累规律研究 总被引：1，自引：0，他引：1
为探讨不同生境下栽培的朝鲜淫羊藿有效成分变化规律，时不同生境栽培的朝鲜淫羊藿不同物候期采收的样品进行检测。结果．各样品总黄酮、淫羊藿苷的含量均远高于药典标准．且郁闭度小比郁闭度大的含量高：于天然次生林下比人工林下栽培含量高；5月花期含量最高．之后下降。8月下旬又升高．因此，朝鲜淫羊藿可于阔叶林下仿生栽培，连年于8月下旬采收． 相似文献
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《海外英语》2007,(5):10-11
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? 相似文献
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《海外英语》2007,(4):36
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. 相似文献
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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. 相似文献
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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. 相似文献
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RUZBEHANI Mohsen 《重庆大学学报(英文版)》2004,3(1):20-25
1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec… 相似文献
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唐芳 《读与写:教育教学刊》2008,5(6)
During interview with English majors, it was found that a majority of students expressed disappointment with their experience of English literature classes. Students' dislike of learning English literature appears to be the major problem of teaching English literature in China. Reader response approach is a good way to solve this problem. In this paper, I explain the rationale behind the reader response approach, such as its origin, definition, features, assumptions, and strategies. Then I illustrate how reader response approach works as a teaching strategy by presenting several teaching models. At last I evaluate its usefuiness for teachers and present the advantages of reader response approach in Chinese context. 相似文献