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1.
纯化刺五加总黄酮最佳洗脱工艺研究   总被引:1,自引:0,他引:1  
采用AB-8大孔吸附树脂和聚酰胺为吸附剂,不同体积浓度的乙醇为洗脱剂,对刺五加总黄酮的最佳纯化洗脱工艺进行研究与探索。实验结果表明刺五加总黄酮最佳纯化洗脱工艺为:AB-8大孔吸附树脂吸附70%乙醇洗脱时洗脱率最高,这些条件的确定为中药刺五加总黄酮的纯化提供了依据。  相似文献   

2.
利用大孔树脂分离纯化黑米花色苷,得到最佳纯化条件.在最佳提取条件下得到黑米花色苷粗提液,利用AB-8大孔树脂对其进行纯化,研究各个因素对吸附率和解吸率的影响.静态吸附平衡时间为4 h,吸附液pH值为2.0,解吸时间为1.5 h,60%乙醇洗脱效果最佳.动态吸附上样液质量浓度0.5 mg/mL、流速为1.0 mL/min时吸附效果最好,解吸流速为1.0 mL/min、60%乙醇洗脱剂解吸效果最佳.在最佳纯化工艺条件下纯化后的花色苷质量比提高了大约7倍左右,说明AB-8大孔树脂对黑米花色苷具有较好的分离纯化效果.  相似文献   

3.
利用D-101大孔吸附树脂,采用比色法,对富集、纯化苜蓿总皂甙的工艺参数及吸附量的影响因素进行了初步研究.结果表明:当乙醇浓度为70%,吸附时间为2 h时,具有很好的富集、纯化效果;纯化前总皂甙含量为5.67%,纯化后总皂甙含量可达36.02%;并且D-101大孔吸附树脂具有较大的吸附容量,重复使用也可得到较高的吸附量.  相似文献   

4.
利用单因素试验和正交试验优化大孔树脂纯化牛舌草总黄酮的工艺条件.结果表明,影响NKA-9大孔树脂对牛舌草总黄酮吸附能力的各个因素影响力大小为BCA,样品pH值对大孔树脂吸附能力影响显著(P0.05),而乙醇浓度与样品流速对大孔树脂吸附能力影响不显著.确定NKA-9大孔树脂吸附牛舌草总黄酮的最优工艺条件为A1B2C2,即乙醇浓度10%、样品pH值5、样品流速2 BV·h-1.NKA-9大孔树脂对牛舌草总黄酮有较好的纯化效果,且工艺重复性和稳定性良好.  相似文献   

5.
选择适用于分离纯化雪莲注射液的大孔吸附树脂和其最佳纯化条件.通过静态吸附与解析和动态吸附与解析对3种大孔吸附树脂进行筛选.实验表明采用DM301型大孔吸附树脂分离纯化效果好,所用三种大孔树脂中的DM301型大孔吸附树脂能更好地分离纯化天山雪莲总黄酮.  相似文献   

6.
选择适合玉米苞叶总黄酮纯化的大孔树脂,确定最佳纯化条件.以吸附量和解吸量为指标,采用静态吸附-解吸附方法,筛选最佳树脂;采用动态吸附-解吸方法,确定最佳纯化条件.选择S-8大孔树脂对黄酮的纯化效果较好,吸附平衡时间为5 h,解吸平衡时间为1.5 h,最佳上柱pH值为4~5,以1.0 mL/min的吸附流速上样,再以80...  相似文献   

7.
本研究以炮制的干天麻为原料,水提醇沉法提取多糖,大孔吸附树脂纯化,比较了八种大孔树脂(AB-8、D101、LX-17、D301、NKA-9、S-8、LSD-001、ADS-7)对天麻多糖静态吸附-解析效果,筛选出最佳纯化树脂,再研究最佳树脂纯化天麻多糖工艺参数.结果为:八种大孔吸附树脂中D101对天麻多糖的纯化效果最好.样品液浓度、温度、上样速度,洗脱用乙醇浓度、洗脱流速及洗脱体积等因素均对D101树脂吸附分离天麻多糖有影响.所得的最佳纯化工艺为:20℃是较适宜的吸附温度,上样速度1BV/h,上样浓度4mg/mL,进行吸附;吸附饱和平衡后,用解析液浓度60%乙醇,解析速率2BV/h,解析液体积3BV进行动态洗脱.通过该工艺天麻多糖的纯度提高到了65.7%,表明了大孔树脂D101对天麻多糖具有较好的纯化效果.  相似文献   

8.
沙棘叶中黄酮提取及大孔树脂分离纯化槲皮素   总被引:2,自引:0,他引:2  
采用响应面的方法对热碱水提取沙棘叶中黄酮的条件进行优化,较佳工艺条件为pH值11.4,温度75.5℃,质量浓度28.6 mg/mL,提取2.0h,产率为1.23%.磷酸沉淀后采用大孔树脂进行纯化,比较了3种大孔树脂AB-8、DM301、HPD-100对沙棘黄酮的纯化效果,最终选出较佳大孔树脂为AB-8,且当上样液浓度为1.0 mg/mL、pH值为6.0、吸附1.0h后,树脂的吸附率达到最大值.最后用3倍柱体积蒸馏水洗脱除去杂质,用不同体积分数乙醇溶液(30%,50%,70%,80%,90%)进行梯度洗脱,并将解吸液用高效液相色谱(HPLC)进行检测,结果显示80%和90%乙醇解吸液中槲皮素纯度均可到达97%以上.  相似文献   

9.
文章对牛蒡多酚的纯化条件及清除DPPH自由基活性进行了研究,得出大孔树脂AB-8为最佳处理树脂,上柱流速为1 mL/min、上样初始质量浓度为1.68 mg/mL时吸附量最大,采用70%乙醇以2 mL/min速度解吸附,纯化后牛蒡多酚的质量浓度提高了55.36%.同时,采用电子顺磁共振技术(EPR)检测纯化前后的牛蒡多...  相似文献   

10.
目的:筛选刺五加总苷的大孔树脂纯化工艺。方法:以紫丁香苷为对照,采用分光光度法,通过刺五加总苷对5种大孔树脂的静态吸附及解析效果考察,筛选出适合纯化刺五加总苷的大孔树脂,进而通过动态吸附及解析的条件对纯化刺五加总苷的工艺进行优化。结果:D-101型大孔树脂适合纯化刺五加总苷,优化后的最佳富集工艺条件为:上样液质量浓度为0.3 g·ml-1,上样量为50 ml/10 g树脂,依次用7倍树脂体积量水及75%乙醇进行洗脱,浓缩干燥乙醇洗脱液,得刺五加总苷。刺五加总苷转移率达60%以上。结论:本方法适合刺五加总苷的富集。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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