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1.
建立以蒸发光散射检测器(ELSD)测定盾叶薯蓣中薯蓣皂苷含量的高效液相色谱分析方法,考察了不同产地盾叶薯蓣中薯蓣皂苷的含量.色谱柱为HiQsil C18柱(250 mm×4.6 mm,10μm),流动相为乙腈-水(33∶67),流速为0.8 mL/min,柱温为室温.Alltech蒸发光散射检测器参数:载气为氮气,流速为2.5mL/min,漂移管温度为100℃,压力为0.45 Mpa.结果表明:薯蓣皂苷在0.35~3.48μg范围内有良好线性关系,r=0.9976,平均回收率为103.2%,RSD为1.61%(n=6).该方法快速简便,灵敏度高,结果准确可靠,可用于盾叶薯蓣药材中薯蓣皂苷的分析及质量检测与控制.  相似文献   

2.
建立异黄酮衍生物2702中乙醇,乙酸乙酯残留量的测定方法.采用毛细管气相色谱法,色谱柱为DB-Wax(30 m×0.45 mm×0.85 μm)石英毛细管柱;检测器为FID,载气为氮气;柱温为程序升温:起始温度为40℃,保持5 min, 然后以40℃/min的速率升至205℃,保持8 min;气化室温度为225℃.在该色谱条件下,采用甲苯为内标.测得乙醇、乙酸乙酯二种溶剂分别在1.25~87.50 μg/mL(r=0.999 8);1.80~89.90 μg/mL(r=0.999 9)范围内线性关系良好,平均回收率分别为102.0%(RSD=2.8%), 98.4%(RSD=2.3%);检测限分别为0.13 ng,0.17 ng.因此,该毛细管气相色谱法简单、结果准确,适用于本品有机溶剂残留量的测定.  相似文献   

3.
黄山药中薯蓣皂苷元的分光光度法测定   总被引:2,自引:0,他引:2  
采用浓硫酸反应使薯蓣皂苷元显色,对影响显色反应的主要因素进行了试验,用分光光度法在波长为410 nm处对黄山药中薯蓣皂苷元的含量进行测定.试验结果表明:方法的线形范围为2~30 μg/mL (r =0.9996),平均回收率为97.8%;最佳显色条件为:水浴温度50 ℃、反应时间30 min、浓硫酸用量10 mL.该方法适用于薯蓣皂苷元提取过程中的常规检测.  相似文献   

4.
本实验采用安捷伦6820气相色谱仪,氢火焰离子化检测器(F ID),DB-5石英毛细管色谱柱(30m×0.45mm×0.42μm),测定空气和丙酮混合气中丙酮的含量;气相色谱条件为:柱温110℃、进样口温度150℃、检测器温度250℃,氮气为载气,流速1.12mL/m in,分流比14∶1,并绘制出丙酮摩尔分率与峰面积数的标准曲线,相关系数r=0.99967,回收率为100.0%~100.1%。实验采用清水作为吸收剂,吸收空气和丙酮混合气体中的丙酮;通过改变气相流量,用气相色谱仪测定填料吸收塔进口及出口气体丙酮的浓度,得出气相总传质系数K ya与气相流量G的关系曲线,为化工吸收的稳定操作提供有用参考。  相似文献   

5.
目的:采用气相色谱建立复方水合氯醛口服溶液中水合氯醛的含量测定方法。方法:色谱柱:OV-624毛细管柱(30m×0. 53 mm,0. 5μm);柱温:100℃;氢离子火焰检测器(FID)温度:250℃;进样口温度:200℃;载气压力:氮气50 k Pa;氢气50 k Pa;空气流量:40 m L/min;进样量:1μL,进样方式:分流进样(1∶100);在此条件下进行方法学考察。结果:测定复方水合氯醛口服溶液中水合氯醛含量时,各方法学参数满足《中国药典》要求,水合氯醛在125μg/m L~2000μg/m L呈良好线性关系,精密度、重复性RSD分别为1. 96%、2. 97%;样品平均回收率为101. 04%,RSD为2. 03%。结论:气相色谱法适用于复方水合氯醛口服溶液中水合氯醛含量测定,且操作方便,简单易行。  相似文献   

6.
采用气相色谱法及残留溶剂测定法对莫西沙星侧链的残留溶剂进行测定.色谱柱采用6%氰丙基苯基—94%二甲基聚硅氧烷为固定液的毛细管柱(DB-624,30m×0.32mm×1.8μm),柱温80℃,维持5min后,以8℃/min的速率升温至200℃,维持15min;检测器为氢火焰离子化检测器,检测温度为270℃,进样口温度为250℃,载气流速3.0mL/min,分流比10∶1.实验结果显示,本方法可以有效、准确地检测出莫西沙星侧链的残留溶剂.  相似文献   

7.
顶空法测定头孢匹胺钠中的溶剂残留   总被引:3,自引:0,他引:3  
采用顶空气相色谱法对头孢匹胺钠中的残留溶剂DMF进行测定.使用熔融石英毛细管柱HP-INNOWax(30 m × 0.25 mm×0.25μm);检测器FID;载气N2;程序升温:初始温度为60℃,以20℃/min的速度升温至100℃,停留2 min,以10℃/min的速度升温至120℃,再以40℃/min的速度升温至200℃,结束.进样口温度:220℃;检测器温度:250℃;进样体积:1 mL,分流比为20:1;溶剂残留用外标法测定,分析结果表明,该方法对DMF的检测限量为0.004 g/L,回收率为102%,相对标准偏差为5.4%.该方法操作简单、快速、灵敏、重现性好.  相似文献   

8.
利用毛细管气相色谱法对发酵转化液中丙烯酸浓度的测定进行了系统研究,考察了pH值、萃取剂及萃取条件等因素对检测体系的影响,建立了毛细管气相色谱法分析产腈水解酶菌株筛选体系中丙烯酸浓度的分析方法.色谱条件为:30 m×0.32 mm i. d.,膜厚0.25 μm,PEG-20M固定液,氢焰检测器,熔融石英毛细管柱,柱温为程序升温,初始温度100 ℃,保留1 min后以70 ℃ /min升到200 ℃.检测器温度为230 ℃,汽化室温度为210 ℃,载气(N2)的流速为7.6 mL/min.该方法检测丙烯酸和丙烯腈的相对标准偏差(RSD)(n=5 )分别为0.79%,1.21%.平均回收率(n=5 ) 分别为99.83%,100.38%.该方法操作简便,能准确测定转化体系中产物丙烯酸和底物丙烯腈的含量.  相似文献   

9.
陈勇  王勤  李立  李兵  潘丽娜  王智勇 《广西科学》2008,15(2):178-180
以薯蓣皂苷元为对照品,采用三氯甲烷-乙酸乙酯(10∶1)为展开剂,对绵萆薢药材进行薄层色谱鉴别;采用HypersilODS2C18柱(5μm,4.6mm×250mm),乙腈-水(90∶10)为流动相,203nm为检测波长,测定绵萆薢药材中薯蓣皂苷元的含量。绵萆薢药材薄层色谱鉴别中,薯蓣皂苷元与其他成分分离良好,能较好的鉴别出薯蓣皂苷元;HPLC定量分析中,薯蓣皂苷元进样量2.16~19.44μg范围内呈良好的线性关系,平均回收率为100.92%,RSD为1.30%。本方法简便,结果准确,重现性好,可以用于绵萆薢药材的质量控制。  相似文献   

10.
建立了花色蛤中扑草净含量的毛细管气相色谱测定方法.采用SPL进样口,毛细管色谱柱rtx-5(弱极性,30m×0.25 mm×0.25μm),火焰光度检测器(FPD)进行检测.进样口温度,250℃,分流比5∶1,载气流速,1.47 m L/min;线速率控制方式:线速率,37 cm/s,柱室温度,100℃保持1 min,以30℃/min升至220℃,保持10 min;检测器温度,250℃,氢气气流量,40 m L/min,空气流量,60 m L/min.实验结果表明:方法简单、快速、重现性好,平均回收率大于85%,RSD小于6.0%,线性范围为0.05~1μg/m L,检出限(定性限)为0.001 mg/kg.  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.
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   

13.
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   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
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   

16.
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   

17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
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   

19.
20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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