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1.
HPLC法测定鲜天麻中多指标成分的含量   总被引:1,自引:0,他引:1  
建立了高效液相色谱测定鲜天麻中天麻素、对羟基苯甲醇、对羟基苯甲醛、腺苷、巴利森苷A、4,4'-二羟基二苄基醚6种成分含量的方法。采用Agilent 1120高效液相系统,YMC-PEAK ODS-A column(250 mm×4.6 mm,5μm)色谱柱,流动相为0.1%甲酸水溶液(A)-甲醇溶液(B),梯度洗脱:0~5 min,5%B;5~65 min,5%~40%B;65~80 min,40%~100%B;分析时间80 mins;流速1 m L/min;柱温25℃;进样量50μL。其中天麻素、对羟基苯甲醇、对羟基苯甲醛、腺苷、巴利森苷A、4,4'-二羟基二苄基醚6种成分在线性范围内均具有良好的线性关系(R≥0.999 2);平均回收率在94.20%~99.68%,相对标准偏差小于1.96%。在不同品种的鲜天麻中,6种成分的量存在差异,红天麻各成分含量稍高于乌天麻。同一品种天麻中,巴利森苷类成分含量较高,腺苷和4,4'-二羟基二苄基醚含量均较低,且鲜天麻中提取的天麻素等6种成分在8 h内稳定。该方法分离效果与重复性好、快速、简便,能够为客观、全面地研究天麻药材提供参考。  相似文献   

2.
目的建立测定天麻素原料药中天麻素的含量及有关物质的高效液相色谱法.方法采用Hypersil C18色谱柱,甲醇·0.01moL·L^-1磷酸二氢钠(8:92,磷酸调节pH至4.0±0.1)为流动相,检测波长为220nm,流速1.0mL·min^-1.结果天麻素在2.5~40.0ug·mL^-1范围内,峰面积与其浓度线性关系良好(r=0.9999),高、中、低3种浓度的平均加样回收率为99.7%~100.3%RSD为0.44%~0.82%,有关物质的限量为1.0%.结论本法准确、简便、快速,适用于天麻素原料药的质量控制.  相似文献   

3.
采用晒干、不同温度烘干、微波干燥和冻干方式干燥天麻,利用HPLC方法测定多指标成分的含量。建立天麻活性成分多指标同时检测的分析方法,考察不同干燥方式对天麻外观性状及多指标成分含量的影响。以天麻素、对羟基苯甲醇、巴利森苷A作为主要指标,只考虑温度因素时,80 ℃烘干效果最好;以腺苷含量作为主要指标,晒干处理方式下腺苷含量最高;以对羟基苯甲醛作为主要指标,晒干跟微波干燥的样品含量差距不大,冻干方式含量最低。天麻多指标成分含量同时检测方法的建立,可根据实际需要选择不同的采后干燥加工方式,综合考虑外观性状及指标成分含量的变化,天麻60 ℃烘干效果较好。  相似文献   

4.
乌天麻挥发性成分分析及抗菌活性研究   总被引:1,自引:0,他引:1  
用水蒸汽蒸馏法提取乌天麻次生块茎(箭麻)的挥发性成分,用气相色谱质谱法(GC—MS)对其挥发性化学成分进行分离鉴定,并用面积归一化计算各成分相对含量.结果显示:乌天麻挥发性成分包含36种成份,20种成分已确定,大约占总质量的76.392%.乌天麻中主要是4-甲基-苯酚(20.409%)、苯乙烯(12.607%)、1-甲乙醚十六烷酸(8.842%)芳香醚(6.038%).用乌天麻挥发性成分进行的抗菌试验表明:乌天麻挥发性成分对包括米曲霉、黄曲霉、小麦纹枯病、茶轮斑病和青霉在内的部分植物病源真菌有一定的抑菌活性.这将为天麻挥发油进一步开发利用提供了实验基础.  相似文献   

5.
石荠苧(Mosta punctulata)不同器官的精油分布特征   总被引:2,自引:0,他引:2  
采用水蒸汽蒸馏法测定石荠苧不同器官的精油含量,色谱/质谱/数据系统联用方法分析石荠苧不同器官精油的化学组成.结果表明:石荠苧干叶的精油含量为(2.515士0.044)%,石荠苧干茎的精油含量为(0.205士0.018)%,石荠苧干全草的精油含量为(1.535士0.035)%.干叶的精油含量是干茎的12倍多,叶是石荠苧精油分布的主要器官.从石荠苧不同器官的精油中共检测到142种成分,鉴定出以甲基丁香油酚、律草烯、石竹烯、β-金合欢烯、桉叶油素、τ-榄香烯、α-香柠檬烯、侧柏酮为主的70种成分.其中从干叶精油中鉴定出58种成分,占其精油总量的97.935%;从干茎精油中鉴定出56种成分,占其精油总量的94.524%;从干草精油中鉴定出64种成分,占其精油总量的98.008%.叶、茎、全草三者精油的化学组成基本相同.  相似文献   

6.
应用0.25%与0.125%的胰酶分离绵羊毛囊细胞,获得2种不同形态的毛囊细胞;其次,对比分析了热消化法与冷消化法对分离毛囊细胞的影响,结果表明:热消化法优于冷消化法;同时,观察到新疆细毛羊与阿勒泰羊的毛囊细胞形态基本一致。  相似文献   

7.
主要对添加了不同量稀土Co的Cu-3.0Ni-0.64Si合金进行加工工艺和性能研究.最佳加工工艺为:Cu-3.0Ni-0.64Si合金热轧时,铸锭热轧开坯温度为930℃,保温时间60min;固溶处理温度为900℃,保温时间60min;然后经过约80%的冷变形再进行时效处理,时效处理温度480℃,保温时间210min.研究结果表明:添加0.06wt%Ce的Cu-3.0Ni-0.64Si合金具有最佳综合性能;电导率最高达到48.9%IACS,抗拉强度达到733.17MPa.  相似文献   

8.
RP-HPLC法测定虎杖中大黄素的含量   总被引:3,自引:0,他引:3  
李建忠  朱文学 《甘肃科技》2003,19(12):116-117
目的:测定中药材虎杖中大黄素的含量。方法:采用RP—HPLC法进行测定。使用C18柱,乙腈—水—冰醋酸(60:40:1)为流动相;检测波长为437nm。结果:大黄素在0.01498~0.07490μg范围内呈良好的线性关系,r=0.9993,平均回收率为99.60%(n=5),RSD=1.82%。结论:此方法简便,准确灵敏,分离度好,可作为其质量控制指标。  相似文献   

9.
建立了天麻中天麻素含量的超高效液相色谱紫外检测法,主要采用Waters Acquity-BEH C18柱(1.7μm,50 mm×2.5 mm),以乙腈和0.1%甲酸为流动相,流速0.3 m L/min进行梯度洗脱,乙腈洗脱浓度和时间为:3%(0 min)—20%(3 min)—3%(4 min)—3%(5 min),柱温30℃,进样量5μL,检测时间5 min,二极管阵列检测器,检测波长220 nm。该色谱分析条件下,天麻素能达到较好的基线分离,检测时间为5 min,经方法学考察可知该方法可行性高,能准确分析天麻中的天麻素,方法快速、方便、准确可行。  相似文献   

10.
山苍子油微胶囊化及其抗氧化作用   总被引:2,自引:0,他引:2  
以新鲜的山苍子为原料,采用超声波辅助水蒸汽蒸馏法提取山苍子粗油,应用正交设计以β-环糊精为壁材对山苍子油微胶囊化,并且对山苍子油的抗氧化作用进行了研究.实验结果表明,β-环糊精可以很好的包埋山苍子油,其最佳包埋工艺为:山苍子油与β-环糊精用量比为1mL:4g;β-环糊精与水用量比为1g:25mL;搅拌温度为65℃;乳化剂用量为0.3%,此外山苍子粗油具有较好的抗氧化效果,可以有效的清除羟自由基、超氧自由基。  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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