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1.
采用微波辅助萃取—高效液相色谱法测定了苦丁茶中熊果酸的含量.苦丁茶粉碎后以乙醇为溶剂,微波高火提取4 min,采用高效液相色谱法(HPLC)测定熊果酸的含量.色谱柱为InertsilC18柱(5μm,4.6×150 mm);流动相为甲醇/水(体积比90∶10),流速为0.8mL/min,柱温40℃,检测波长为210nm.结果表明熊果酸在0.0996~0.4980mg/mL范围内线性关系良好,平均回收率为100.8%,RSD=1.12%,苦丁茶中熊果酸的含量为14.55 mg/g.  相似文献   

2.
高效液相色谱法测定木瓜中熊果酸的含量研究   总被引:1,自引:0,他引:1  
采用HPLC法,以YPW-Kromasil TMC18为色谱柱,甲醇-水-冰醋酸(90∶10∶0.1)为流动相,流速0.6mL/min,柱温25℃,检测波长210 nm,建立了木瓜中熊果酸的高效液相色谱含量测定方法.结果表明:熊果酸在0.03~0.15 mg/mL范围内呈良好的线性关系,该方法的平均回收率为101.8%(n=5),RSD为1.16%.  相似文献   

3.
2mol.l-1KCl溶液可作为无土栽培中基质的NH4 —N和NO3-—N的提取剂,其固∶液=1∶5,振荡时间为30min,NH4 —N测定采用靛酚蓝比色法,测定波长为645nm,标准曲线的回归方程为:A=0.7358C 0.0044,r=0.9994(n=7),回收率为:103.6%。NO3-—N测定采用紫外分光光度法,测定波长为205nm,标准曲线的回归方程为:A=0.5654C 0.0127,r=0.9994(n=9),回收率为:102.4%。  相似文献   

4.
目的建立了青叶胆中齐墩果酸和熊果酸的反相高效液相色谱-光电二极管阵列检测器(RP-HPLC-PDAD)定量分析方法。方法采用95%乙醇为溶剂超声提取,色谱柱为Kromasil C18柱(4.6mm×250 mm,5μm),柱温30℃。以甲醇∶水∶磷酸(88∶12∶0.15,v/v/v)为流动相等度洗脱,流速0.9 m L·min-1,采用光电二极管阵列检测器进行检测,检测波长210 nm。结果齐墩果酸进样量在0.1048~2.6200μg时,与峰面积呈良好的线性关系(r=0.9999),平均回收率为96.9%,RSD为1.7%(n=9);熊果酸进样量在0.2304~5.7600μg时,与峰面积呈良好的线性关系(r=0.9999),平均回收率为97.5%,RSD为1.5%(n=9)。结论方法准确,操作简便,数据可靠,可用于青叶胆中齐墩果酸和熊果酸的含量测定。  相似文献   

5.
建立金匮肾气丸中三萜类成分的质量比测定方法.以HPLC法选用SymmetryC18柱(4.6 mm×250 mm,5μm)测定该复方中茯苓酸、熊果酸及齐墩果酸的质量比.茯苓酸质量比测定色谱条件为:检测波长为242 nm;流动相为甲醇-水-磷酸(75∶25∶0.2);流速为1 mL/min;柱温为30℃.熊果酸及齐墩果酸的色谱条件:检测波长为215 nm;流动相为乙腈-甲醇-水-乙酸胺(62.5∶15.5∶22∶0.55);流速为0.8 mL/min;柱温为30℃.茯苓酸、熊果酸及齐墩果酸的质量比分别为0.116 mg/g、0.287 mg/g、0.134 mg/g.结果表明,该方法简便、准确、重现性好,适用于金匮肾气丸中三萜酸类成分的定量分析.  相似文献   

6.
在Cs- 930薄层扫描仪上以紫外反射吸收方式 ,灵敏快速测定了解热止痛散中对乙酰氨基酚和咖啡因的含量 .扫描参数 :对乙酰氨基酚λs=2 4 8.5nm ,λR=34 0 .0nm ,咖啡因λs=2 73.0nm ,λR=34 0 .0nm ,散射参数Sx=3.采用双波长反射线齿型扫描 ,狭缝 1.2mm× 1.2mm ,所用薄层板为GF2 54,薄层厚度 0 .4mm ,展开剂为氯仿 :甲醇∶醋酸乙酯∶冰醋酸 =10∶2∶2∶0 .2 (体积比 ) ,平均回收率对乙酰氨基酚为 95.6% ,咖啡因为 10 8.4 %  相似文献   

7.
目的建立黔产蒲公英中熊果酸含量的高效液相色谱测定方法.方法采用 Dikma C18柱(250 mm ×4.6 mm,5μm),流动相为甲醇-乙腈-0.5%醋酸铵(16:65:20),柱温25℃,流速1.0 mL·min-1,检测波长为215 nm.结果熊果酸在10.2~102μg·mL-1范围内与峰面积呈良好的线性(r2=0.9999),平均加样回收率为99.52%,RSD为1.47%(n =6).结论所用方法简便、快速、准确,首次提出以熊果酸含量作为黔产蒲公英的质量控制指标  相似文献   

8.
薄层扫描法测定强骨颗粒中黄芪甲苷的含量   总被引:2,自引:0,他引:2  
采用双波长薄层扫描法,以氯仿—甲醇—水(13∶7∶2)的下层溶液为展开剂,10%硫酸乙醇溶液显色,在105℃烘约5 min,λS=530 nm,λR=700 nm条件下扫描,以测定强骨颗粒中黄芪甲苷含量.结果表明:样品中黄芪甲苷分离完全,阴性供试品无干扰,黄芪甲苷在1.982~9.91μg范围内呈良好线性关系,r=0.9957,平均回收率为98.4%,RSD为2.1%,测得3批强骨颗粒中黄芪甲苷的平均含量为0.0639 mg/g.  相似文献   

9.
本文以采集于湘潭县的枸骨根为材料,选用熊果酸为对照品,5%香草醛—冰乙酸和高氯酸为显色剂,以分光光度法测定枸骨根中总三萜的含量.实验结果表明:在549 nm波长下,标准品在4.4~26.4 mg/L范围内,吸光度与含量呈良好的线性关系,其回归方程为:y=0.0357x-0.0809,R2=0.9984.样品吸光度在5~40 min内相对比较稳定,其三萜含量为3.20%,RSD值为0.31%.该方法操作简便,快速,灵敏度高,重复性好.  相似文献   

10.
建立一种高效、准确、稳定的桐叶熊果酸和齐墩果酸测定方法,测定湖南省湘西地区桐叶药材中熊果酸和齐墩果酸含量.采用高效液相色谱(HPLC)法,色谱条件依次为,色谱柱:TADE-PAKAF-C18柱(250 mm×4.6 mm,5 μm);流动相:乙腈-甲醇-0.5%醋酸铵溶液(体积比61∶18∶21);流速:1 mL/min;检测波长:210 nm;柱温:35 ℃;进样量:10 μL.结果表明:齐墩果酸与熊果酸分离度为1.73,均符合要求;熊果酸和齐墩果酸对照品分别在0.497 6~9.952 0 μg/mL和0.126 1~2.523 0 μg/mL范围内线性关系良好(r均为0.999 9);熊果酸、齐墩果酸平均加样回收率分别为99.93%,98.97%;湘西产桐叶含熊果酸4.54~7.07 mg/g,含齐墩果酸2.50~3.20 mg/g.HPLC法分离效果好、灵敏度高、准确度高,是检测桐叶中熊果酸、齐墩果酸含量的科学有效手段.  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 Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
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   

15.
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   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
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   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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