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1.
合成了一种手性离子液体[ CHTA+][Tf2N-]((S)-(-)-(3-氯-2-羟丙基)三甲基铵双三氟甲烷磺酰亚胺),将其用作新型气相色谱固定相,考察了它的色谱性能.研究结果表明:该离子液体作为气相色谱固定相在容量因子为1.29时,其理论塔板数为2 057块/米;对醇类、酮类、芳香族化合物、位置异构体以及一些外消旋体具有良好的分离效果. 相似文献
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目的建立三七枸杞酒中多糖含量的测定方法。方法三七枸杞酒中的多糖经苯酚-硫酸法显色后,利用紫外-可见分光光度计在490 nm波长处进行比色测定。结果苯酚-硫酸法测定三七枸杞酒中多糖方法稳定,精密度高,线性范围为0.02~0.1 mg/m L,相关系数为r~2=0.9998,平均回收率为99.89%。结论苯酚-硫酸法可作为三七枸杞酒中多糖含量测定的方法。 相似文献
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Effect of different cleaning processes on saponins' loss rate and total ash clearance rate of Notoginseng and heavy metal health risk assessment
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Yang Ye Tian Mengyuan Guo Lan‐Ping Liu Dahui Qu Yu Cui Xiu‐Ming 《Journal of Food Processing and Preservation》2018,42(1)
Total ash clearance rates and saponins' loss rates of Panax notoginseng rhizome, root tuber, and rootlet all increased with a prolonged washing time and the rising of water temperature. Under the same conditions, the total ash clearance rates of fresh P. notoginseng were significantly higher than those dried. Meanwhile, the saponins' loss rates were opposite. The highest daily intake of bioavailability heavy metals was rootlet. However, all of that was significantly lower than the recommended daily intake, and both the target hazard quotients and hazard index values were lower than 1. Conclusion, it is effective to decrease washing time and water temperature in order to reduce the loss of saponins of P. notoginseng on the premise that ash content of Notoginseng conforms to standard of Chinese Pharmacopeias. Safety risk assessments of heavy metals based on bioavailability can further reduce the health risk of the heavy metal exposure of Notoginseng.
Practical applications
Notoginseng possesses the functions of hemostatic and promoting blood circulation. Clay on the surface of Notoginseng contains high content of heavy metal and induces the exceeding of standard. Washing is the most effective way to clean heavy metal attached on Notoginseng. However, research about the washing technology of Panax notoginseng is still blank. Heavy metals in Notoginseng that are taken orally are much higher than the amount actually absorbed by humans. In such a condition, the risk of heavy metals in Notoginseng will be overestimated, which may bring unnecessary loss to the development of Notoginseng industry. Therefore, this experiment researches the remaining of heavy metal under different washing water temperature and washing time. Also, we evaluate the bioavailability and risk of heavy metals in Notoginseng that are washed in an optimum condition. In this way, we provide technological parameters for the washing operation in processing P. notoginseng and referential data to set the quantity standard of heavy metal in Notoginseng. 相似文献6.
本研究旨在探讨云南野生香薷油对子代小鼠学习记忆功能的影响。将昆明种小鼠从受孕第1d开始分为空白对照、阳性对照、低、中、高剂量5个组,用云南野生香薷油灌胃至断乳,断乳d小鼠按孕鼠剂量灌胃至出生49d后做Morris水迷宫实验,之后测定小鼠脑组织神经递质和肝、脑组织的脂肪酸。结果表明,与空白对照组比较,定位航行实验的第5d各组均有统计学意义(P〈0.01)。空间探索实验的阳性对照组有统计学意义(P〈0.05)。脑神经递质TPro、NO、AchE:阳性、中、高剂量组均有统计学意义(P〈0.05)。肝脂肪酸结果中阳性和高剂量组的ALA有统计学意义(P〈0.05);脑组织脂肪酸结果:高剂量组的油酸和ALA有统计学意义(P〈0.05)。可见,富含α-亚麻酸的香薷油具有部分改善子代小鼠学习记忆的功能,其作用可能与喂养此香薷油使脑组织的TPro升高,NO、AchE降低;肝和脑组织的α-亚麻酸升高有关。 相似文献
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Distinguishing the Chinese materia medica Tiepishihu from similar Dendrobium species of the same genus using histological and microscopic method
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Kun‐Zi Yu Hua Yan Hai‐Chuan Tai Nan‐Ping Zhang Xian‐Long Cheng Zeng‐Xi Guo Shuang‐Cheng Ma Feng Wei 《Microscopy research and technique》2017,80(7):745-755
The Chinese Materia Medica, Tiepishihu, used as a tonic for over one thousand years, is a well‐known precious medicine in China. According to the Chinese Pharmacopoeia, its source is the species Dendrobium officinale Kimura et Migo, which is distinguished from other species in Dendrobium genus. However, these species from the same genus are similar with Tiepishihu and caused confusion in the market. To find a quick and simple method to distinguish Tiepishihu from other similar species, histologic and microscopic methods were combined together to investigate the transverse section of stem of Tiepishihu and other similar species. Phloroglucinol test solution with hydrochloric acid was used to reveal the lignified tissue by staining the transverse section of Tiepishihu and similar species. Results revealed the unique identification characteristics to distinguish Tiepishihu from similar species, which were difficult to distinguish by other methods. The identification characteristics of Tiepishihu include the cells of vascular bundle sheath were stained red, parenchyma cells were not stained red. What's more, other species can be distinguished from each other with microscopic and histological characteristics. These characteristics proved stable and can be easily observed by normal light microscopic examination. This method is rapid, accurate, stable, and inexpensive. 相似文献
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Chung-Ming Own 《Expert systems with applications》2009,36(2):3007-3016
Representation and manipulation of the vague concepts of partially true knowledge in the development of machine intelligence is a wide and challenging field of study. How to extract of approximate facts from vague and partially true statements has drawn significant attention from researchers in the fuzzy information processing. Furthermore, handling uncertainty from this incomplete information has its own necessity. This study theoretically examines a formal method for representing and manipulating partially true knowledge. This method is based on the similarity measure of type-2 fuzzy sets, which are directly used to handle rule uncertainties that type-1 fuzzy sets cannot. The proposed type-2 similarity-based reasoning method is theoretically defined and discussed herein, and the reasoning results are applied to show the usefulness with the comparison of the general fuzzy sets. 相似文献
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《Food chemistry》2001,74(2):209-216
Free and glycosidically-bound flavour compounds of acerola fruit were isolated and identified by GC and GC–MS analysis. Among the 46 compounds identified in the volatile fraction, the alcohols (3-methyl-but-3-en-1-ol, 3-methyl-butan-1-ol and 2-methyl-butan-1-ol) were predominant. Two other classes, aromatic compounds and esters, can participate in the fruity and fresh aroma of acerola. Among the 42 aglycones identified for the first time in this fruit, aliphatic alcohols and norisoprenoids were the main components. The latter were present in free form and only in traces. The hydrolysis of these aglycones could increase the fruity aroma of acerola. Four glucosides and one rutinoside were charaterized by GC–EIMS of their TFA derivatives. 相似文献
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Effects of LaCl_3 on photosynthesis and the accumulation of tanshinones and salvianolic acids in Salvia miltiorrhiza seedlings 总被引:1,自引:1,他引:0
The effects of LaCl3 on the growth,photosynthetic gas-exchange characteristics,chlorophyll fluorescence,and the accumulation of tanshinones and salvianolic acids in Salvia miltiorrhiza seedlings were investigated. The results showed that the increase in photosynthesis induced by LaCl3 might be attributed to the enhanced stomatal conductance of the leaves and the increased level of the photochemical efficiency of PS II. The accumulation of tanshinone IIA and cryptotanshinone was markedly increased with the application of LaCl3 at 20 and 60 mg/L,while tanshinone I was only slightly increased. The content of salvianolic acid B was,however,decreased with the treatment of LaCl3 at 200 mg/L. 相似文献