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1.
为了提升石椒草质量评价的效率,提出了用HPLC法测定石椒草中芦丁的含量。通过对流动相、检测波长、色谱柱、提取溶剂及提取时间等因素的考察,最终确定了HPLC法测定石椒草中芦丁含量的最佳测定条件,即采用Agilent ZORBAX Eclipse Plus C18(4.6 mm×150 mm, 5μm)色谱柱,以甲醇-1%冰醋酸溶液(体积比为30∶70)为流动相,流速为1.0 mL/min,检测波长为257 nm,柱温为25℃。结果表明,芦丁进样量为0.093 34~1.166 75μg(R2=0.999 2)时与峰面积呈现良好的线性关系,精密度、重复性、稳定性试验的RSD均小于2%,平均加样回收率为99.49%,RSD为1.6%。所建立的测定石椒草中芦丁含量的HPLC法,结果准确可靠,供试品制备简便,且具有高灵敏度、高准确性,可为石椒草质量评价标准及质量控制提供数据支持。  相似文献   

2.
桑叶配方颗粒迄今尚没有统一的质量标准。为提升桑叶配方颗粒的内在质量,对其物质基准评价方法进行了研究。选取具有代表性产地的15批桑叶制备物质基准,采用高效液相色谱法,以芦丁、异槲皮苷、紫云英苷作为评价指标,确定桑叶物质基准的出膏率范围、标志性成分含量及转移率范围,采用超高效液相色谱法,建立物质基准UPLC特征图谱,并对其主要成分进行指认。结果表明:15批物质基准中,芦丁转移率为19.94%~34.05%,异槲皮苷转移率为11.67%~43.58%,紫云英苷转移率为10.73%~43.05%;物质基准特征图谱中,标定了14个共有峰,指认出7个色谱峰,分别为新绿原酸、绿原酸、咖啡酸、芦丁、异槲皮苷、槲皮素-3-O-(6″-O-丙二酰基)-β-D-葡萄糖苷、紫云英苷。所建立的基准评价方法为桑叶配方颗粒质量标准的制定及其后续大规模生产提供了数据基础。  相似文献   

3.
为实现对车前子配方颗粒多指标成分的质量评价,解决中药化学对照品分离难度大、单体性质不稳定、供应价格高等问题,建立了一测多评法同时测定车前子配方颗粒中的3种有效成分含量。以京尼平苷酸为内标物,建立与芦丁、毛蕊花糖苷的相对校正因子,测定其含量,同时采用外标法测定这3种成分的含量,比较两种方法的结果差异。结果表明:京尼平苷酸、芦丁、毛蕊花糖苷分别在0.804~8.040,0.172~1.720,0.158~1.580μg范围内线性关系良好(r≥0.999),平均加样回收率分别为102.52%,102.00%和101.86%,RSD值分别为1.64%,1.06%和1.07%。一测多评法所得结果与外标法差异不明显,具有较高的重复性、稳定性及可信度,可为车前子配方颗粒的质量评价提供参考依据。  相似文献   

4.
为了提高薄荷配方颗粒的质量标准,建立其多指标定量评价体系,采用HPLC法同时测定薄荷配方颗粒中咖啡酸、橙皮苷、迷迭香酸、香叶木苷、香蜂草苷和蒙花苷6种成分的含量.采用Poroshell 120 EC-C18(4.6 mm×250 mm,5μm)色谱柱,以甲醇(A)-乙腈(B)-5%冰乙酸(C)为流动相,梯度洗脱,流速为...  相似文献   

5.
为了实现浮小麦配方颗粒的质量控制和评价,采用高效液相色谱法,以Waters XSelect? HSS T3(4.6 mm×250 mm, 5μm)为色谱柱,在甲醇-水为流动相、梯度洗脱、柱温为30℃、流速为1.0 mL/min、检测波长为260 nm的条件下,建立了浮小麦配方颗粒的特征图谱及4种核苷类成分的含量测定方法。共确定了13批浮小麦配方颗粒特征图谱中的8个共有峰,并全部获得指认,分别为尿嘧啶、胞苷、次黄嘌呤、尿苷、腺嘌呤、鸟苷、色氨酸、腺苷,各共有峰相对保留时间的RSD均小于2.0%。尿嘧啶、尿苷、鸟苷、腺苷分别在0.001 9~0.047 3 mg/mL、0.003 9~0.098 2 mg/mL、0.002 8~0.070 1 mg/mL、0.002 9~0.073 0 mg/mL范围内线性关系良好(r=1.000 0),平均加样回收率分别为99.0%、100.7%、101.2%、101.8%。所建立的核苷类成分含量测定方法准确、高效、重复性好,可用于浮小麦配方颗粒的质量控制。  相似文献   

6.
为了考察知母饮片、水煎剂和配方颗粒之间化学成分的差异,采用HPLC法对三者的指纹图谱进行了相关性研究。选用Inertsil ODS-3柱(250mm×4.6mm,5μm),以乙腈为流动相A,1%醋酸为流动相B进行梯度洗脱,流速为1mL/min,柱温为30℃,检测波长为265nm,采集时间为100min,分别建立10批知母饮片、10批知母水煎剂与10批知母配方颗粒的指纹图谱。结果显示,10批知母配方颗粒HPLC指纹图谱的9个指纹峰均可在饮片中得到追踪,相似度均大于0.95,从9个共有峰中指认出芒果苷,知母饮片、水煎剂和配方颗粒的主要化学成分基本相同。本研究所建立的指纹图谱方法重复性、稳定性好,可用于饮片、配方颗粒生产过程中的质量控制。  相似文献   

7.
为提高佛手配方颗粒的质量评价标准,利用佛手标准汤剂控制佛手配方颗粒的内在质量。以15批不同产地的佛手饮片为原料,制备佛手标准汤剂,建立含量测定方法,以柚皮苷、橙皮苷为指标成分,测定了15批佛手标准汤剂的相关含量。结果表明:柚皮苷、橙皮苷分别在0.025 1~0.125 5,0.160 5~0.802 3μg范围内线性关系良好(r=0.999 9),平均加样回收率分别为102.27%和101.48%,重复性考察RSD值分别为0.78%和0.89%,12 h稳定性考察RSD值分别为0.59%和1.46%。所提出的方法能同时测定柚皮苷和橙波苷两种成分,节约了分析时间,提高了佛手产品的质量标准。  相似文献   

8.
为了全面反映瓜蒌配方颗粒所含多种组分,明确瓜蒌配方颗粒HPLC指纹图谱的测定方法,对10批瓜蒌配方颗粒进行了HPLC指纹图谱测定及相似度评价。采用HPLC方法,色谱柱为GL Sciences公司InertSustain AQ-C_(18)柱(4.6 nm×250 nm,5μm),以甲醇-0.1%甲酸水溶液为流动相,梯度洗脱,检测波长为260 nm,流速为0.8 mL/min,柱温为25℃,对瓜蒌配方颗粒指纹图谱测定结果进行了相似度评价。结果表明,10批瓜蒌配方颗粒指纹图谱中呈现16个共有峰,相似度均大于0.960,表明瓜蒌配方颗粒具有良好的一致性;此外,在16个共有峰中指认出腺嘌呤、尿苷2个化学成分。瓜蒌配方颗粒指纹图谱反映了瓜蒌配方颗粒的多组分面貌,可为瓜蒌配方颗粒的多组分质量控制提供参考依据。  相似文献   

9.
为全面反映合欢皮标准汤剂多种组分的面貌,明确合欢皮标准汤剂的HPLC指纹图谱,对15批合欢皮标准汤剂进行了HPLC指纹图谱测定及相似度评价。采用HPLC方法,色谱柱为Waters Symmetry shield RP C_(18)柱(4.6 mm×250 mm,5μm),以乙腈-0.04%磷酸溶液为流动相进行梯度洗脱,检测波长为210 nm,流速为1 mL/min,柱温为25℃,对照指纹图谱对合欢皮标准汤剂进行相似度评价及聚类分析。结果表明,15批合欢皮标准汤剂指纹图谱中呈现10个共有峰,相似度为0.967~0.998,表明合欢皮标准汤剂具有良好的一致性;此外,在10个共有峰中指认出(-)-丁香树脂酚-4-O-β-D-呋喃芹糖基-(1→2)-β-D-吡喃葡萄糖苷、异槲皮苷2个化学成分。因此,合欢皮标准汤剂指纹图谱反映了合欢皮标准汤剂的多组分面貌,具有良好的可行性,可为合欢皮配方颗粒的多组分质量控制提供参考。  相似文献   

10.
为了评价不同厂家白芷配方颗粒的产品质量,建立了白芷配方颗粒的特征图谱与主成分分析方法。采用Waters Uplc Class H超高效液相色谱仪与Agilent Zorbax Eclipse Plus C18(2.1mm×100mm,1.7μm)色谱柱,以乙腈-水为流动相,柱温为25℃,流速为0.2mL/min,检测波长为254nm,利用指纹图谱相似度评价软件提取白芷配方颗粒特征图谱中的特征成分,使用参照物标定5个特征峰的成分;采用SPSS 19.0软件进行主成分分析,给出了不同厂家白芷配方颗粒在2个主成分上的分布图,并对不同厂家白芷配方颗粒进行了综合评分。结果表明:10批白芷配方颗粒特征图谱确定的13个特征峰中,指认出了花椒毒酚、水合氧化前胡素、欧前胡素、蛇床子素、异欧前胡素5种成分;以回归得到的3个主成分的矩阵回归系数与方差贡献值的乘积之和作为10批样品的综合评分,排名第一的综合评分为1.77。基于UPLC特征图谱与主成分分析法能够快速、有效地检测和评价白芷配方颗粒。  相似文献   

11.
《Telecommunications Policy》2014,38(10):914-932
This article analyzes the engagement of Japanese, Korean and Chinese participants in the development of Internet standards at IETF on the basis of four quantitative metrics: attendance, patenting, authorship and leadership. The results are strikingly divergent. Japanese involvement in Internet standardization began early and Japan was, for many years, second only to the U.S. in terms of IETF participation. Though Japanese participation has declined since the early 2000s, Japan remains a major contributor to IETF standardization. Korean involvement in IETF has always been significant, but below the levels of Japan and major European countries. Korean participation in IETF has also declined over the past decade, and has been dominated by one firm, Samsung. Though meaningful Chinese involvement in IETF did not begin until the mid-2000s, it has rapidly expanded in recent years. Today, China is a major player in numerous areas of Internet standardization in terms of three metrics (participation, patenting and leadership), and is rapidly gaining in terms of document authorship as well. Most of China׳s recent IETF involvement can be attributed to Huawei, though other Chinese firms have recently begun to increase their participation in the organization. Thus, contrary to some views that China׳s engagement with standardization is primarily one of indigenous innovation and “catching up”, China׳s experience with IETF demonstrates deliberate and effective engagement with a major Western standards-development organization on its own terms.  相似文献   

12.
增强Linux系统安全性的措施   总被引:2,自引:0,他引:2  
L inux系统的安全取决于系统管理员如何来管理它。本文探讨了一系列可以增强安全性的技巧与策略 ,包括 :系统安装原则、BIOS安全、口令安全策略、设计帐户自动注销功能、文件系统和日志安全策略、使用 SSH及 TCP-WRAPPERS,隐藏系统信息、删除所有特殊帐户、关闭控制台程序、限制系统中的 SUID/ SGID程序等。本文最后向 L inux系统管理员提出了一些安全管理方面的建议  相似文献   

13.
This paper explores the idea that a sense of school subject image is a necessary feature of curriculum management and a potent force for change. The discussion centres on the view that all school subjects have an image and that if those intimately involved with the subject do not control the image then someone else does! In such circumstances the image is the product of past encounters and old euphemisms and is unlikely to hold the changed realities.The UK developments in Design and Technology education (the term Design and Technology is used to denote the school subject defined under this heading by the UK National Curriculum, 1995) have created something of an image problem which has interesting international parallels. Some of these problems are due to clearly discernible internal tensions and an ambiguous relationship with other subject areas.Through greater attention to subject image internal controversies might be acknowledged and resolved, relationships with other subject areas can be more meaningfully understood and practitioners can be helped to make sense of curriculum change.  相似文献   

14.
快速成形技术的应用及热点分析   总被引:1,自引:0,他引:1  
基于快速成形技术的原理,展示了快速成形技术在快速模具制造、金属零件直接成形、反求工程等领域的广泛应用,总结了快速成形制造技术研究的热点,即研发新材料和新设备、提高成形精度、建立RPM的反求工程系统、建立成形技术的统一标准和扩大成形技术的应用领域。  相似文献   

15.
概括性介绍了 CIS(Corporate Identity System)的三大基本组成,并阐述了它与现代企业管理密不可分的相互联系及所处的举足轻重的地位,指出导入CIS是现代企业谋求发展的重要手段。  相似文献   

16.
企业管理水平的好坏直接影响着企业的经济效益,运用HSE管理能提高企业管理水平,HSE管理模式将健康,安全,环境三者视为一个有机的整体。HSE管理认为人的安全是第一位的,人是创造财富的原动力,是企业的最大财产,HSE管理体系强调的是“蝴蝶效应”。  相似文献   

17.
《Telecommunications Policy》2014,38(5-6):496-513
We analyze the state of the art of indicators on e-government, e-health, e-procurement and e-participation. We survey the main methodological properties of these indicators, and highlight their heuristic potential. Further, we address empirically the issue of the explanation of the availability scores, i.e. how the supply of the various e-services in each country is affected by political, institutional and socio-economic differences, and is followed by actual usage. The econometric analysis uncovers the importance of broadband penetration and higher education as drivers for most of the types of e-services and users (citizens and businesses). Moreover, a corruption-free and agile public sector proves to be an important pre-condition for more effective supply and usage. Despite data limitations and the complexity of the underlying diffusion phenomena, our study is the first truly longitudinal contribution aimed at disentangling the common drivers of such an important phenomenon – the e-services availability and usage across European countries. As such, this work appears useful to inform the policy debate and practice, in a phase characterized by a prospective reorientation of the public e-services provision and policy agenda.  相似文献   

18.
频率标准源可以提供精确的标准频率,在测定频率标准源的各项性能指标时,要求测试系统必须具有很高的比对精度。所设计的频率标准比对系统采取多级倍频 混频方式使频率偏差逐级扩大后再测量,从而避免了直接进行高次倍频的困难,提高了测量精度,可以对高精度的频率标准的准确度、长短期频率稳定度进行快速测量,是一种高精度时畴参数测量系统。  相似文献   

19.
This special section aims to investigate the interaction of global and local forces in shaping agrifood governance. It starts from the recognition that a multitude of actors and norms shape today’s agrifood system. The resulting opaqueness of the systems makes it extremely difficult to understand and explain processes and outcomes of agrifood governance. Given the sustainability challenges facing the agrifood system, improvements in our understanding of what the interaction of global and local actors and norms means on the ground are urgently needed, however. The section, therefore, analyses agrifood governance in India across a selected group of cases. It does so by employing a systematic framework emphasizing the material and ideational dimensions of power and their interaction. The section has chosen India as the setting in which to analyze this interaction due to the crucial role the food demand and supply of this rising power plays in today’s agrifood system. This article provides the special sections’ analytical framework, which uses the interplay of material and ideational dimensions of power as a focal lens. In addition, the article applies this framework to an empirical study of the political conflict around GMO foods in India, specifically the case of ‘Golden Rice’.  相似文献   

20.
研究了石油化工企业的燕汽计量情况,着重对蒸汽热量计量的合理性进行了分析,阐述了蒸汽热量计量的依据及计算方法,以及蒸气热量计量对节能降耗的重要意义.  相似文献   

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