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1.
银杏根中黄酮类化合物的提取及其含量测定   总被引:6,自引:0,他引:6  
采用浸泡与回流的方法从银杏根中提取黄酮,用721型分光光度计测得总黄酮含量为6.89%.高效液相色谱法检测银杏根中槲皮素百分率为1.24%,是黄酮类化合物中含量较高的成分.紫外-可见分光光度法确定最佳检测波长为370 nm.  相似文献   

2.
根据小檗碱的性质 ,可采用紫外分光光度法 ,薄层色谱—分光光度法 ,柱色谱紫外分光光度法 ,酸性染料比色法 ,正交函数、双波长、三波长分光光度法 ,薄层扫描法 ,高效液相色谱法等进行中药制剂中小檗碱含量的测定  相似文献   

3.
旨在建立一种实验室快速、简便地测定天麻素的方法.采用紫外分光光度法(UV)在220 nm波长下进行天麻素的紫外检测,并采用高效液相色谱法对该结果进行验证,结果表明:采用紫外分光光度法检测的结果与采用高效液相色谱法检测的结果并无显著性差异(P〉0.05),因此说明在220 nm波长下进行天麻素的紫外检测是一种简便、快捷且准确的方法.  相似文献   

4.
3种水中头孢曲松钠检测方法的对比   总被引:1,自引:0,他引:1  
分别对褪色分光光度法、紫外分光光度法和高效液相色谱法3种头孢曲松钠的检测方法进行了实验对比,实验得到3种方法的检出限分别是0.13、0.028和0.004 7mg·L~(-1),回收率分别达到78%~81%、92%~96%和99%~101%.实验对高效液相色谱法色谱条件进行了优化,采用Waters~XBridge C18(150 mm×4.6 mm,5μm)色谱柱为固定相,柱温30℃,流动相为甲醇和0.02 mol·L~(-1)三乙胺水溶液(体积比为27∶73),检测波长254nm.实验结果表明,精度要求较高的情况下可以选用高效液相色谱法,在检出限不低于0.03mg·L~(-1)的情况下,紫外分光光度法由于所需仪器价格低廉,不失为一种便捷的方法,尤其在厂矿企业具有巨大的应用价值.  相似文献   

5.
优选炒薏苡仁的炮制工艺。以炒制温度、炒制时间为考察因素,以甘油三油酸酯含量为评价指标,采用高效液相色谱法测定:C_(18)(4.6 mm×150 mm,5μm),流动相乙腈-二氯甲烷(65∶35),流速1.00 m L/min,柱温30℃,检测波长237 nm,蒸发光散射检测器,载气流速1.70 L/min,漂移管温度74℃[1]。炒制温度对炒薏苡仁含量影响不大,考虑炒制时间与成品性状之间的关系,根据生产和成本的需要,确定炒薏苡仁最佳炮制工艺为:投药量为25 kg,转速为25 r/min,炒制温度为360℃,炒制3~4 min,成品质量符合传统要求。  相似文献   

6.
给出了两种“益心酮”粉针剂含量的测定方法:紫外-可见分光光度法和高效液相色谱法,结果两种方法均能很好地测定其有效成分,达到质量控制的目的。  相似文献   

7.
用高效液相色谱法和紫外分光光度法分别测定某纺织厂排出的废水中己内酰胺的含量.高效液相色谱法以SPD-20A为检测器,检测波长为280 nm,流动相为甲醇:水=35:65,流动相流速为1.0 mL/min.在该检测条件下,己内酰胺的保留时间为6.017 min,相对标准偏差为3.9%,最低检测浓度0.1 mg/L,外标法测得废水中己内酰胺的含量为1.0mg/L;紫外分光光度法以蒸馏水为空白,测得己内酰胺在281 nm处有吸收,此方法检测限为0.5 mg/L,相对标准偏差为4.5%,废水中己内酰胺的含量为1.10 mg/L.  相似文献   

8.
微波萃取高效液相色谱分析菱角中甾醇类化合物   总被引:2,自引:0,他引:2  
采用微波萃取法首次从野生菱角皮和菱角仁中提取到甾醇类化合物,并用紫外-可见分光光度法和高效液相色谱法对提取液中总甾醇含量和其中β-谷甾醇的含量进行了分析测定.通过实验优选出最佳微波提取条件:以95%乙醇为提取剂,在微波功率为420 W,料液比为1:5(mg/mL)的条件下提取60 s.液相色谱分析采用HRC-ODS(150 mm×4.6 mm ID)反相色谱柱,流动相为V(甲醇):V(水)=0.96:0.04,流速为1.0 mL/min,检测波长为215nm,甾醇类化合物在6 min内得到了很好的分离.经检测菱角皮及菱角仁中总甾醇含量分别为0.624和0.813 mg/g,其β-谷甾醇的含量分别为0.508和0.716 mg/g.该方法测得菱角皮和菱角仁中β-谷甾醇含量的精密度分别为0.596%和0.268%.  相似文献   

9.
随着我国环境质量的不断恶化,环境监测受到重视,越来越多的现代仪器分析技术被应用到环境监测领域,用来提高监测结果的准确度和灵敏度。该文详细介绍了我国环境污染的特点,以及传统环境监测分析技术的不足之处,对紫外-可见分光光度法、原子吸收分光光度法、气象色谱法、高效液相色谱法、离子色谱法、电感耦合等离子体质谱法、气-质联用技术等现代仪器分析技术在环境监测中的应用进行了详细阐述,并对未来环境监测与保护的发展做了展望。  相似文献   

10.
本文对紫外-可见分光光度法的原理、应用、发展进行了简要的介绍,为我们准确、高效在实验分析过程中应用紫外-可见分光光度法提供了依据。  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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